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wdenkc6097192002-11-03 00:24:07 +00001#
Wolfgang Denkeca3aeb2013-06-21 10:22:36 +02002# (C) Copyright 2000 - 2013
wdenkc6097192002-11-03 00:24:07 +00003# Wolfgang Denk, DENX Software Engineering, wd@denx.de.
4#
Wolfgang Denkeca3aeb2013-06-21 10:22:36 +02005# SPDX-License-Identifier: GPL-2.0+
wdenkc6097192002-11-03 00:24:07 +00006#
7
8Summary:
9========
10
wdenk24ee89b2002-11-03 17:56:27 +000011This directory contains the source code for U-Boot, a boot loader for
wdenke86e5a02004-10-17 21:12:06 +000012Embedded boards based on PowerPC, ARM, MIPS and several other
13processors, which can be installed in a boot ROM and used to
14initialize and test the hardware or to download and run application
15code.
wdenkc6097192002-11-03 00:24:07 +000016
17The development of U-Boot is closely related to Linux: some parts of
wdenk24ee89b2002-11-03 17:56:27 +000018the source code originate in the Linux source tree, we have some
19header files in common, and special provision has been made to
wdenkc6097192002-11-03 00:24:07 +000020support booting of Linux images.
21
22Some attention has been paid to make this software easily
23configurable and extendable. For instance, all monitor commands are
24implemented with the same call interface, so that it's very easy to
25add new commands. Also, instead of permanently adding rarely used
26code (for instance hardware test utilities) to the monitor, you can
27load and run it dynamically.
28
29
30Status:
31=======
32
33In general, all boards for which a configuration option exists in the
wdenk24ee89b2002-11-03 17:56:27 +000034Makefile have been tested to some extent and can be considered
wdenkc6097192002-11-03 00:24:07 +000035"working". In fact, many of them are used in production systems.
36
Robert P. J. Day7207b362015-12-19 07:16:10 -050037In case of problems see the CHANGELOG file to find out who contributed
38the specific port. In addition, there are various MAINTAINERS files
39scattered throughout the U-Boot source identifying the people or
40companies responsible for various boards and subsystems.
wdenkc6097192002-11-03 00:24:07 +000041
Robert P. J. Day7207b362015-12-19 07:16:10 -050042Note: As of August, 2010, there is no longer a CHANGELOG file in the
43actual U-Boot source tree; however, it can be created dynamically
44from the Git log using:
Robert P. J. Dayadb9d852012-11-14 02:03:20 +000045
46 make CHANGELOG
47
wdenkc6097192002-11-03 00:24:07 +000048
49Where to get help:
50==================
51
wdenk24ee89b2002-11-03 17:56:27 +000052In case you have questions about, problems with or contributions for
Robert P. J. Day7207b362015-12-19 07:16:10 -050053U-Boot, you should send a message to the U-Boot mailing list at
Peter Tyser0c325652008-09-10 09:18:34 -050054<u-boot@lists.denx.de>. There is also an archive of previous traffic
55on the mailing list - please search the archive before asking FAQ's.
56Please see http://lists.denx.de/pipermail/u-boot and
57http://dir.gmane.org/gmane.comp.boot-loaders.u-boot
wdenkc6097192002-11-03 00:24:07 +000058
59
Wolfgang Denk218ca722008-03-26 10:40:12 +010060Where to get source code:
61=========================
62
Robert P. J. Day7207b362015-12-19 07:16:10 -050063The U-Boot source code is maintained in the Git repository at
Wolfgang Denk218ca722008-03-26 10:40:12 +010064git://www.denx.de/git/u-boot.git ; you can browse it online at
65http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary
66
67The "snapshot" links on this page allow you to download tarballs of
Marcel Ziswiler11ccc332008-07-09 08:17:15 +020068any version you might be interested in. Official releases are also
Wolfgang Denk218ca722008-03-26 10:40:12 +010069available for FTP download from the ftp://ftp.denx.de/pub/u-boot/
70directory.
71
Anatolij Gustschind4ee7112008-03-26 18:13:33 +010072Pre-built (and tested) images are available from
Wolfgang Denk218ca722008-03-26 10:40:12 +010073ftp://ftp.denx.de/pub/u-boot/images/
74
75
wdenkc6097192002-11-03 00:24:07 +000076Where we come from:
77===================
78
79- start from 8xxrom sources
wdenk24ee89b2002-11-03 17:56:27 +000080- create PPCBoot project (http://sourceforge.net/projects/ppcboot)
wdenkc6097192002-11-03 00:24:07 +000081- clean up code
82- make it easier to add custom boards
83- make it possible to add other [PowerPC] CPUs
84- extend functions, especially:
85 * Provide extended interface to Linux boot loader
86 * S-Record download
87 * network boot
Marcel Ziswiler11ccc332008-07-09 08:17:15 +020088 * PCMCIA / CompactFlash / ATA disk / SCSI ... boot
wdenk24ee89b2002-11-03 17:56:27 +000089- create ARMBoot project (http://sourceforge.net/projects/armboot)
wdenkc6097192002-11-03 00:24:07 +000090- add other CPU families (starting with ARM)
wdenk24ee89b2002-11-03 17:56:27 +000091- create U-Boot project (http://sourceforge.net/projects/u-boot)
Magnus Lilja0d28f342008-08-06 19:32:33 +020092- current project page: see http://www.denx.de/wiki/U-Boot
wdenk24ee89b2002-11-03 17:56:27 +000093
94
95Names and Spelling:
96===================
97
98The "official" name of this project is "Das U-Boot". The spelling
99"U-Boot" shall be used in all written text (documentation, comments
100in source files etc.). Example:
101
102 This is the README file for the U-Boot project.
103
104File names etc. shall be based on the string "u-boot". Examples:
105
106 include/asm-ppc/u-boot.h
107
108 #include <asm/u-boot.h>
109
110Variable names, preprocessor constants etc. shall be either based on
111the string "u_boot" or on "U_BOOT". Example:
112
113 U_BOOT_VERSION u_boot_logo
114 IH_OS_U_BOOT u_boot_hush_start
wdenkc6097192002-11-03 00:24:07 +0000115
116
wdenk93f19cc2002-12-17 17:55:09 +0000117Versioning:
118===========
119
Thomas Weber360d8832010-09-28 08:06:25 +0200120Starting with the release in October 2008, the names of the releases
121were changed from numerical release numbers without deeper meaning
122into a time stamp based numbering. Regular releases are identified by
123names consisting of the calendar year and month of the release date.
124Additional fields (if present) indicate release candidates or bug fix
125releases in "stable" maintenance trees.
wdenk93f19cc2002-12-17 17:55:09 +0000126
Thomas Weber360d8832010-09-28 08:06:25 +0200127Examples:
Wolfgang Denkc0f40852011-10-26 10:21:21 +0000128 U-Boot v2009.11 - Release November 2009
Thomas Weber360d8832010-09-28 08:06:25 +0200129 U-Boot v2009.11.1 - Release 1 in version November 2009 stable tree
Jelle van der Waa0de21ec2016-10-30 17:30:30 +0100130 U-Boot v2010.09-rc1 - Release candidate 1 for September 2010 release
wdenk93f19cc2002-12-17 17:55:09 +0000131
132
wdenkc6097192002-11-03 00:24:07 +0000133Directory Hierarchy:
134====================
135
Peter Tyser8d321b82010-04-12 22:28:21 -0500136/arch Architecture specific files
Masahiro Yamada6eae68e2014-03-07 18:02:02 +0900137 /arc Files generic to ARC architecture
Peter Tyser8d321b82010-04-12 22:28:21 -0500138 /arm Files generic to ARM architecture
Peter Tyser8d321b82010-04-12 22:28:21 -0500139 /m68k Files generic to m68k architecture
Peter Tyser8d321b82010-04-12 22:28:21 -0500140 /microblaze Files generic to microblaze architecture
Peter Tyser8d321b82010-04-12 22:28:21 -0500141 /mips Files generic to MIPS architecture
Macpaul Linafc1ce82011-10-19 20:41:11 +0000142 /nds32 Files generic to NDS32 architecture
Peter Tyser8d321b82010-04-12 22:28:21 -0500143 /nios2 Files generic to Altera NIOS2 architecture
Robert P. J. Day33c77312013-09-15 18:34:15 -0400144 /openrisc Files generic to OpenRISC architecture
Stefan Roesea47a12b2010-04-15 16:07:28 +0200145 /powerpc Files generic to PowerPC architecture
Rick Chen3fafced2017-12-26 13:55:59 +0800146 /riscv Files generic to RISC-V architecture
Robert P. J. Day7207b362015-12-19 07:16:10 -0500147 /sandbox Files generic to HW-independent "sandbox"
Peter Tyser8d321b82010-04-12 22:28:21 -0500148 /sh Files generic to SH architecture
Robert P. J. Day33c77312013-09-15 18:34:15 -0400149 /x86 Files generic to x86 architecture
Peter Tyser8d321b82010-04-12 22:28:21 -0500150/api Machine/arch independent API for external apps
151/board Board dependent files
Xu Ziyuan740f7e52016-08-26 19:54:49 +0800152/cmd U-Boot commands functions
Peter Tyser8d321b82010-04-12 22:28:21 -0500153/common Misc architecture independent functions
Robert P. J. Day7207b362015-12-19 07:16:10 -0500154/configs Board default configuration files
Peter Tyser8d321b82010-04-12 22:28:21 -0500155/disk Code for disk drive partition handling
156/doc Documentation (don't expect too much)
157/drivers Commonly used device drivers
Robert P. J. Day33c77312013-09-15 18:34:15 -0400158/dts Contains Makefile for building internal U-Boot fdt.
Peter Tyser8d321b82010-04-12 22:28:21 -0500159/examples Example code for standalone applications, etc.
160/fs Filesystem code (cramfs, ext2, jffs2, etc.)
161/include Header Files
Robert P. J. Day7207b362015-12-19 07:16:10 -0500162/lib Library routines generic to all architectures
163/Licenses Various license files
Peter Tyser8d321b82010-04-12 22:28:21 -0500164/net Networking code
165/post Power On Self Test
Robert P. J. Day7207b362015-12-19 07:16:10 -0500166/scripts Various build scripts and Makefiles
167/test Various unit test files
Peter Tyser8d321b82010-04-12 22:28:21 -0500168/tools Tools to build S-Record or U-Boot images, etc.
wdenkc6097192002-11-03 00:24:07 +0000169
wdenkc6097192002-11-03 00:24:07 +0000170Software Configuration:
171=======================
172
173Configuration is usually done using C preprocessor defines; the
174rationale behind that is to avoid dead code whenever possible.
175
176There are two classes of configuration variables:
177
178* Configuration _OPTIONS_:
179 These are selectable by the user and have names beginning with
180 "CONFIG_".
181
182* Configuration _SETTINGS_:
183 These depend on the hardware etc. and should not be meddled with if
184 you don't know what you're doing; they have names beginning with
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +0200185 "CONFIG_SYS_".
wdenkc6097192002-11-03 00:24:07 +0000186
Robert P. J. Day7207b362015-12-19 07:16:10 -0500187Previously, all configuration was done by hand, which involved creating
188symbolic links and editing configuration files manually. More recently,
189U-Boot has added the Kbuild infrastructure used by the Linux kernel,
190allowing you to use the "make menuconfig" command to configure your
191build.
wdenkc6097192002-11-03 00:24:07 +0000192
193
194Selection of Processor Architecture and Board Type:
195---------------------------------------------------
196
197For all supported boards there are ready-to-use default
Holger Freytherab584d62014-08-04 09:26:05 +0200198configurations available; just type "make <board_name>_defconfig".
wdenkc6097192002-11-03 00:24:07 +0000199
200Example: For a TQM823L module type:
201
202 cd u-boot
Holger Freytherab584d62014-08-04 09:26:05 +0200203 make TQM823L_defconfig
wdenkc6097192002-11-03 00:24:07 +0000204
Robert P. J. Day7207b362015-12-19 07:16:10 -0500205Note: If you're looking for the default configuration file for a board
206you're sure used to be there but is now missing, check the file
207doc/README.scrapyard for a list of no longer supported boards.
wdenkc6097192002-11-03 00:24:07 +0000208
Simon Glass75b3c3a2014-03-22 17:12:59 -0600209Sandbox Environment:
210--------------------
211
212U-Boot can be built natively to run on a Linux host using the 'sandbox'
213board. This allows feature development which is not board- or architecture-
214specific to be undertaken on a native platform. The sandbox is also used to
215run some of U-Boot's tests.
216
Jagannadha Sutradharudu Teki6b1978f2014-08-31 21:19:43 +0530217See board/sandbox/README.sandbox for more details.
Simon Glass75b3c3a2014-03-22 17:12:59 -0600218
219
Simon Glassdb910352015-03-03 08:03:00 -0700220Board Initialisation Flow:
221--------------------------
222
223This is the intended start-up flow for boards. This should apply for both
Robert P. J. Day7207b362015-12-19 07:16:10 -0500224SPL and U-Boot proper (i.e. they both follow the same rules).
Simon Glassdb910352015-03-03 08:03:00 -0700225
Robert P. J. Day7207b362015-12-19 07:16:10 -0500226Note: "SPL" stands for "Secondary Program Loader," which is explained in
227more detail later in this file.
228
229At present, SPL mostly uses a separate code path, but the function names
230and roles of each function are the same. Some boards or architectures
231may not conform to this. At least most ARM boards which use
232CONFIG_SPL_FRAMEWORK conform to this.
233
234Execution typically starts with an architecture-specific (and possibly
235CPU-specific) start.S file, such as:
236
237 - arch/arm/cpu/armv7/start.S
238 - arch/powerpc/cpu/mpc83xx/start.S
239 - arch/mips/cpu/start.S
240
241and so on. From there, three functions are called; the purpose and
242limitations of each of these functions are described below.
Simon Glassdb910352015-03-03 08:03:00 -0700243
244lowlevel_init():
245 - purpose: essential init to permit execution to reach board_init_f()
246 - no global_data or BSS
247 - there is no stack (ARMv7 may have one but it will soon be removed)
248 - must not set up SDRAM or use console
249 - must only do the bare minimum to allow execution to continue to
250 board_init_f()
251 - this is almost never needed
252 - return normally from this function
253
254board_init_f():
255 - purpose: set up the machine ready for running board_init_r():
256 i.e. SDRAM and serial UART
257 - global_data is available
258 - stack is in SRAM
259 - BSS is not available, so you cannot use global/static variables,
260 only stack variables and global_data
261
262 Non-SPL-specific notes:
263 - dram_init() is called to set up DRAM. If already done in SPL this
264 can do nothing
265
266 SPL-specific notes:
267 - you can override the entire board_init_f() function with your own
268 version as needed.
269 - preloader_console_init() can be called here in extremis
270 - should set up SDRAM, and anything needed to make the UART work
271 - these is no need to clear BSS, it will be done by crt0.S
272 - must return normally from this function (don't call board_init_r()
273 directly)
274
275Here the BSS is cleared. For SPL, if CONFIG_SPL_STACK_R is defined, then at
276this point the stack and global_data are relocated to below
277CONFIG_SPL_STACK_R_ADDR. For non-SPL, U-Boot is relocated to run at the top of
278memory.
279
280board_init_r():
281 - purpose: main execution, common code
282 - global_data is available
283 - SDRAM is available
284 - BSS is available, all static/global variables can be used
285 - execution eventually continues to main_loop()
286
287 Non-SPL-specific notes:
288 - U-Boot is relocated to the top of memory and is now running from
289 there.
290
291 SPL-specific notes:
292 - stack is optionally in SDRAM, if CONFIG_SPL_STACK_R is defined and
293 CONFIG_SPL_STACK_R_ADDR points into SDRAM
294 - preloader_console_init() can be called here - typically this is
Ley Foon Tan0680f1b2017-05-03 17:13:32 +0800295 done by selecting CONFIG_SPL_BOARD_INIT and then supplying a
Simon Glassdb910352015-03-03 08:03:00 -0700296 spl_board_init() function containing this call
297 - loads U-Boot or (in falcon mode) Linux
298
299
300
wdenkc6097192002-11-03 00:24:07 +0000301Configuration Options:
302----------------------
303
304Configuration depends on the combination of board and CPU type; all
305such information is kept in a configuration file
306"include/configs/<board_name>.h".
307
308Example: For a TQM823L module, all configuration settings are in
309"include/configs/TQM823L.h".
310
311
wdenk7f6c2cb2002-11-10 22:06:23 +0000312Many of the options are named exactly as the corresponding Linux
313kernel configuration options. The intention is to make it easier to
314build a config tool - later.
315
Ashish Kumar63b23162017-08-11 11:09:14 +0530316- ARM Platform Bus Type(CCI):
317 CoreLink Cache Coherent Interconnect (CCI) is ARM BUS which
318 provides full cache coherency between two clusters of multi-core
319 CPUs and I/O coherency for devices and I/O masters
320
321 CONFIG_SYS_FSL_HAS_CCI400
322
323 Defined For SoC that has cache coherent interconnect
324 CCN-400
wdenk7f6c2cb2002-11-10 22:06:23 +0000325
Ashish Kumarc055cee2017-08-18 10:54:36 +0530326 CONFIG_SYS_FSL_HAS_CCN504
327
328 Defined for SoC that has cache coherent interconnect CCN-504
329
wdenkc6097192002-11-03 00:24:07 +0000330The following options need to be configured:
331
Kim Phillips26281142007-08-10 13:28:25 -0500332- CPU Type: Define exactly one, e.g. CONFIG_MPC85XX.
wdenkc6097192002-11-03 00:24:07 +0000333
Kim Phillips26281142007-08-10 13:28:25 -0500334- Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS.
Wolfgang Denk6ccec442006-10-24 14:42:37 +0200335
Lei Wencf946c62011-02-09 18:06:58 +0530336- Marvell Family Member
337 CONFIG_SYS_MVFS - define it if you want to enable
338 multiple fs option at one time
339 for marvell soc family
340
Kumar Gala66412c62011-02-18 05:40:54 -0600341- 85xx CPU Options:
York Sunffd06e02012-10-08 07:44:30 +0000342 CONFIG_SYS_PPC64
343
344 Specifies that the core is a 64-bit PowerPC implementation (implements
345 the "64" category of the Power ISA). This is necessary for ePAPR
346 compliance, among other possible reasons.
347
Kumar Gala66412c62011-02-18 05:40:54 -0600348 CONFIG_SYS_FSL_TBCLK_DIV
349
350 Defines the core time base clock divider ratio compared to the
351 system clock. On most PQ3 devices this is 8, on newer QorIQ
352 devices it can be 16 or 32. The ratio varies from SoC to Soc.
353
Kumar Gala8f290842011-05-20 00:39:21 -0500354 CONFIG_SYS_FSL_PCIE_COMPAT
355
356 Defines the string to utilize when trying to match PCIe device
357 tree nodes for the given platform.
358
Scott Wood33eee332012-08-14 10:14:53 +0000359 CONFIG_SYS_FSL_ERRATUM_A004510
360
361 Enables a workaround for erratum A004510. If set,
362 then CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV and
363 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY must be set.
364
365 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV
366 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 (optional)
367
368 Defines one or two SoC revisions (low 8 bits of SVR)
369 for which the A004510 workaround should be applied.
370
371 The rest of SVR is either not relevant to the decision
372 of whether the erratum is present (e.g. p2040 versus
373 p2041) or is implied by the build target, which controls
374 whether CONFIG_SYS_FSL_ERRATUM_A004510 is set.
375
376 See Freescale App Note 4493 for more information about
377 this erratum.
378
Prabhakar Kushwaha74fa22e2013-04-16 13:27:44 +0530379 CONFIG_A003399_NOR_WORKAROUND
380 Enables a workaround for IFC erratum A003399. It is only
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -0800381 required during NOR boot.
Prabhakar Kushwaha74fa22e2013-04-16 13:27:44 +0530382
Prabhakar Kushwaha9f074e62014-10-29 22:33:09 +0530383 CONFIG_A008044_WORKAROUND
384 Enables a workaround for T1040/T1042 erratum A008044. It is only
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -0800385 required during NAND boot and valid for Rev 1.0 SoC revision
Prabhakar Kushwaha9f074e62014-10-29 22:33:09 +0530386
Scott Wood33eee332012-08-14 10:14:53 +0000387 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY
388
389 This is the value to write into CCSR offset 0x18600
390 according to the A004510 workaround.
391
Priyanka Jain64501c62013-07-02 09:21:04 +0530392 CONFIG_SYS_FSL_DSP_DDR_ADDR
393 This value denotes start offset of DDR memory which is
394 connected exclusively to the DSP cores.
395
Priyanka Jain765b0bd2013-04-04 09:31:54 +0530396 CONFIG_SYS_FSL_DSP_M2_RAM_ADDR
397 This value denotes start offset of M2 memory
398 which is directly connected to the DSP core.
399
Priyanka Jain64501c62013-07-02 09:21:04 +0530400 CONFIG_SYS_FSL_DSP_M3_RAM_ADDR
401 This value denotes start offset of M3 memory which is directly
402 connected to the DSP core.
403
Priyanka Jain765b0bd2013-04-04 09:31:54 +0530404 CONFIG_SYS_FSL_DSP_CCSRBAR_DEFAULT
405 This value denotes start offset of DSP CCSR space.
406
Priyanka Jainb1359912013-12-17 14:25:52 +0530407 CONFIG_SYS_FSL_SINGLE_SOURCE_CLK
408 Single Source Clock is clocking mode present in some of FSL SoC's.
409 In this mode, a single differential clock is used to supply
410 clocks to the sysclock, ddrclock and usbclock.
411
Aneesh Bansalfb4a2402014-03-18 23:40:26 +0530412 CONFIG_SYS_CPC_REINIT_F
413 This CONFIG is defined when the CPC is configured as SRAM at the
Bin Menga1875592016-02-05 19:30:11 -0800414 time of U-Boot entry and is required to be re-initialized.
Aneesh Bansalfb4a2402014-03-18 23:40:26 +0530415
Tang Yuantianaade2002014-04-17 15:33:46 +0800416 CONFIG_DEEP_SLEEP
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -0800417 Indicates this SoC supports deep sleep feature. If deep sleep is
Tang Yuantianaade2002014-04-17 15:33:46 +0800418 supported, core will start to execute uboot when wakes up.
419
Daniel Schwierzeck6cb461b2012-04-02 02:57:56 +0000420- Generic CPU options:
421 CONFIG_SYS_BIG_ENDIAN, CONFIG_SYS_LITTLE_ENDIAN
422
423 Defines the endianess of the CPU. Implementation of those
424 values is arch specific.
425
York Sun5614e712013-09-30 09:22:09 -0700426 CONFIG_SYS_FSL_DDR
427 Freescale DDR driver in use. This type of DDR controller is
428 found in mpc83xx, mpc85xx, mpc86xx as well as some ARM core
429 SoCs.
430
431 CONFIG_SYS_FSL_DDR_ADDR
432 Freescale DDR memory-mapped register base.
433
434 CONFIG_SYS_FSL_DDR_EMU
435 Specify emulator support for DDR. Some DDR features such as
436 deskew training are not available.
437
438 CONFIG_SYS_FSL_DDRC_GEN1
439 Freescale DDR1 controller.
440
441 CONFIG_SYS_FSL_DDRC_GEN2
442 Freescale DDR2 controller.
443
444 CONFIG_SYS_FSL_DDRC_GEN3
445 Freescale DDR3 controller.
446
York Sun34e026f2014-03-27 17:54:47 -0700447 CONFIG_SYS_FSL_DDRC_GEN4
448 Freescale DDR4 controller.
449
York Sun9ac4ffb2013-09-30 14:20:51 -0700450 CONFIG_SYS_FSL_DDRC_ARM_GEN3
451 Freescale DDR3 controller for ARM-based SoCs.
452
York Sun5614e712013-09-30 09:22:09 -0700453 CONFIG_SYS_FSL_DDR1
454 Board config to use DDR1. It can be enabled for SoCs with
455 Freescale DDR1 or DDR2 controllers, depending on the board
456 implemetation.
457
458 CONFIG_SYS_FSL_DDR2
Robert P. J. Day62a3b7d2016-07-15 13:44:45 -0400459 Board config to use DDR2. It can be enabled for SoCs with
York Sun5614e712013-09-30 09:22:09 -0700460 Freescale DDR2 or DDR3 controllers, depending on the board
461 implementation.
462
463 CONFIG_SYS_FSL_DDR3
464 Board config to use DDR3. It can be enabled for SoCs with
York Sun34e026f2014-03-27 17:54:47 -0700465 Freescale DDR3 or DDR3L controllers.
466
467 CONFIG_SYS_FSL_DDR3L
468 Board config to use DDR3L. It can be enabled for SoCs with
469 DDR3L controllers.
470
471 CONFIG_SYS_FSL_DDR4
472 Board config to use DDR4. It can be enabled for SoCs with
473 DDR4 controllers.
York Sun5614e712013-09-30 09:22:09 -0700474
Prabhakar Kushwaha1b4175d2014-01-18 12:28:30 +0530475 CONFIG_SYS_FSL_IFC_BE
476 Defines the IFC controller register space as Big Endian
477
478 CONFIG_SYS_FSL_IFC_LE
479 Defines the IFC controller register space as Little Endian
480
Prabhakar Kushwaha1c407072017-02-02 15:01:26 +0530481 CONFIG_SYS_FSL_IFC_CLK_DIV
482 Defines divider of platform clock(clock input to IFC controller).
483
Prabhakar Kushwahaadd63f92017-02-02 15:02:00 +0530484 CONFIG_SYS_FSL_LBC_CLK_DIV
485 Defines divider of platform clock(clock input to eLBC controller).
486
Prabhakar Kushwaha690e4252014-01-13 11:28:04 +0530487 CONFIG_SYS_FSL_PBL_PBI
488 It enables addition of RCW (Power on reset configuration) in built image.
489 Please refer doc/README.pblimage for more details
490
491 CONFIG_SYS_FSL_PBL_RCW
492 It adds PBI(pre-boot instructions) commands in u-boot build image.
493 PBI commands can be used to configure SoC before it starts the execution.
494 Please refer doc/README.pblimage for more details
495
Prabhakar Kushwaha89ad7be2014-04-08 19:13:34 +0530496 CONFIG_SPL_FSL_PBL
497 It adds a target to create boot binary having SPL binary in PBI format
498 concatenated with u-boot binary.
499
York Sun4e5b1bd2014-02-10 13:59:42 -0800500 CONFIG_SYS_FSL_DDR_BE
501 Defines the DDR controller register space as Big Endian
502
503 CONFIG_SYS_FSL_DDR_LE
504 Defines the DDR controller register space as Little Endian
505
York Sun6b9e3092014-02-10 13:59:43 -0800506 CONFIG_SYS_FSL_DDR_SDRAM_BASE_PHY
507 Physical address from the view of DDR controllers. It is the
508 same as CONFIG_SYS_DDR_SDRAM_BASE for all Power SoCs. But
509 it could be different for ARM SoCs.
510
York Sun6b1e1252014-02-10 13:59:44 -0800511 CONFIG_SYS_FSL_DDR_INTLV_256B
512 DDR controller interleaving on 256-byte. This is a special
513 interleaving mode, handled by Dickens for Freescale layerscape
514 SoCs with ARM core.
515
York Sun1d71efb2014-08-01 15:51:00 -0700516 CONFIG_SYS_FSL_DDR_MAIN_NUM_CTRLS
517 Number of controllers used as main memory.
518
519 CONFIG_SYS_FSL_OTHER_DDR_NUM_CTRLS
520 Number of controllers used for other than main memory.
521
Prabhakar Kushwaha44937212015-11-09 16:42:07 +0530522 CONFIG_SYS_FSL_HAS_DP_DDR
523 Defines the SoC has DP-DDR used for DPAA.
524
Ruchika Gupta028dbb82014-09-09 11:50:31 +0530525 CONFIG_SYS_FSL_SEC_BE
526 Defines the SEC controller register space as Big Endian
527
528 CONFIG_SYS_FSL_SEC_LE
529 Defines the SEC controller register space as Little Endian
530
Daniel Schwierzeck92bbd642011-07-27 13:22:39 +0200531- MIPS CPU options:
532 CONFIG_SYS_INIT_SP_OFFSET
533
534 Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack
535 pointer. This is needed for the temporary stack before
536 relocation.
537
538 CONFIG_SYS_MIPS_CACHE_MODE
539
540 Cache operation mode for the MIPS CPU.
541 See also arch/mips/include/asm/mipsregs.h.
542 Possible values are:
543 CONF_CM_CACHABLE_NO_WA
544 CONF_CM_CACHABLE_WA
545 CONF_CM_UNCACHED
546 CONF_CM_CACHABLE_NONCOHERENT
547 CONF_CM_CACHABLE_CE
548 CONF_CM_CACHABLE_COW
549 CONF_CM_CACHABLE_CUW
550 CONF_CM_CACHABLE_ACCELERATED
551
552 CONFIG_SYS_XWAY_EBU_BOOTCFG
553
554 Special option for Lantiq XWAY SoCs for booting from NOR flash.
555 See also arch/mips/cpu/mips32/start.S.
556
557 CONFIG_XWAY_SWAP_BYTES
558
559 Enable compilation of tools/xway-swap-bytes needed for Lantiq
560 XWAY SoCs for booting from NOR flash. The U-Boot image needs to
561 be swapped if a flash programmer is used.
562
Christian Rieschb67d8812012-02-02 00:44:39 +0000563- ARM options:
564 CONFIG_SYS_EXCEPTION_VECTORS_HIGH
565
566 Select high exception vectors of the ARM core, e.g., do not
567 clear the V bit of the c1 register of CP15.
568
York Sun207774b2015-03-20 19:28:08 -0700569 COUNTER_FREQUENCY
570 Generic timer clock source frequency.
571
572 COUNTER_FREQUENCY_REAL
573 Generic timer clock source frequency if the real clock is
574 different from COUNTER_FREQUENCY, and can only be determined
575 at run time.
576
Stephen Warren73c38932015-01-19 16:25:52 -0700577- Tegra SoC options:
578 CONFIG_TEGRA_SUPPORT_NON_SECURE
579
580 Support executing U-Boot in non-secure (NS) mode. Certain
581 impossible actions will be skipped if the CPU is in NS mode,
582 such as ARM architectural timer initialization.
583
wdenk5da627a2003-10-09 20:09:04 +0000584- Linux Kernel Interface:
wdenkc6097192002-11-03 00:24:07 +0000585 CONFIG_CLOCKS_IN_MHZ
586
587 U-Boot stores all clock information in Hz
588 internally. For binary compatibility with older Linux
589 kernels (which expect the clocks passed in the
590 bd_info data to be in MHz) the environment variable
591 "clocks_in_mhz" can be defined so that U-Boot
592 converts clock data to MHZ before passing it to the
593 Linux kernel.
wdenkc6097192002-11-03 00:24:07 +0000594 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
Wolfgang Denk218ca722008-03-26 10:40:12 +0100595 "clocks_in_mhz=1" is automatically included in the
wdenkc6097192002-11-03 00:24:07 +0000596 default environment.
597
wdenk5da627a2003-10-09 20:09:04 +0000598 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
599
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -0800600 When transferring memsize parameter to Linux, some versions
wdenk5da627a2003-10-09 20:09:04 +0000601 expect it to be in bytes, others in MB.
602 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
603
Gerald Van Barenfec6d9e2008-06-03 20:34:45 -0400604 CONFIG_OF_LIBFDT
Wolfgang Denkf57f70a2005-10-13 01:45:54 +0200605
606 New kernel versions are expecting firmware settings to be
Gerald Van Baren213bf8c2007-03-31 12:23:51 -0400607 passed using flattened device trees (based on open firmware
608 concepts).
609
610 CONFIG_OF_LIBFDT
611 * New libfdt-based support
612 * Adds the "fdt" command
Kim Phillips3bb342f2007-08-10 14:34:14 -0500613 * The bootm command automatically updates the fdt
Gerald Van Baren213bf8c2007-03-31 12:23:51 -0400614
Wolfgang Denkf57f70a2005-10-13 01:45:54 +0200615 OF_TBCLK - The timebase frequency.
Kumar Galac2871f02006-01-11 13:59:02 -0600616 OF_STDOUT_PATH - The path to the console device
Wolfgang Denkf57f70a2005-10-13 01:45:54 +0200617
Marcel Ziswiler11ccc332008-07-09 08:17:15 +0200618 boards with QUICC Engines require OF_QE to set UCC MAC
619 addresses
Kim Phillips3bb342f2007-08-10 14:34:14 -0500620
Kumar Gala4e253132006-01-11 13:54:17 -0600621 CONFIG_OF_BOARD_SETUP
622
623 Board code has addition modification that it wants to make
624 to the flat device tree before handing it off to the kernel
wdenk6705d812004-08-02 23:22:59 +0000625
Simon Glassc654b512014-10-23 18:58:54 -0600626 CONFIG_OF_SYSTEM_SETUP
627
628 Other code has addition modification that it wants to make
629 to the flat device tree before handing it off to the kernel.
630 This causes ft_system_setup() to be called before booting
631 the kernel.
632
Heiko Schocher3887c3f2009-09-23 07:56:08 +0200633 CONFIG_OF_IDE_FIXUP
634
635 U-Boot can detect if an IDE device is present or not.
636 If not, and this new config option is activated, U-Boot
637 removes the ATA node from the DTS before booting Linux,
638 so the Linux IDE driver does not probe the device and
639 crash. This is needed for buggy hardware (uc101) where
640 no pull down resistor is connected to the signal IDE5V_DD7.
641
Igor Grinberg7eb29392011-07-14 05:45:07 +0000642 CONFIG_MACH_TYPE [relevant for ARM only][mandatory]
643
644 This setting is mandatory for all boards that have only one
645 machine type and must be used to specify the machine type
646 number as it appears in the ARM machine registry
647 (see http://www.arm.linux.org.uk/developer/machines/).
648 Only boards that have multiple machine types supported
649 in a single configuration file and the machine type is
650 runtime discoverable, do not have to use this setting.
651
Niklaus Giger0b2f4ec2008-11-03 22:13:47 +0100652- vxWorks boot parameters:
653
654 bootvx constructs a valid bootline using the following
Bin Meng9e98b7e2015-10-07 20:19:17 -0700655 environments variables: bootdev, bootfile, ipaddr, netmask,
656 serverip, gatewayip, hostname, othbootargs.
Niklaus Giger0b2f4ec2008-11-03 22:13:47 +0100657 It loads the vxWorks image pointed bootfile.
658
Niklaus Giger0b2f4ec2008-11-03 22:13:47 +0100659 Note: If a "bootargs" environment is defined, it will overwride
660 the defaults discussed just above.
661
Aneesh V2c451f72011-06-16 23:30:47 +0000662- Cache Configuration:
663 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot
664 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot
665 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot
666
Aneesh V93bc2192011-06-16 23:30:51 +0000667- Cache Configuration for ARM:
668 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache
669 controller
670 CONFIG_SYS_PL310_BASE - Physical base address of PL310
671 controller register space
672
wdenk6705d812004-08-02 23:22:59 +0000673- Serial Ports:
Andreas Engel48d01922008-09-08 14:30:53 +0200674 CONFIG_PL010_SERIAL
wdenk6705d812004-08-02 23:22:59 +0000675
676 Define this if you want support for Amba PrimeCell PL010 UARTs.
677
Andreas Engel48d01922008-09-08 14:30:53 +0200678 CONFIG_PL011_SERIAL
wdenk6705d812004-08-02 23:22:59 +0000679
680 Define this if you want support for Amba PrimeCell PL011 UARTs.
681
682 CONFIG_PL011_CLOCK
683
684 If you have Amba PrimeCell PL011 UARTs, set this variable to
685 the clock speed of the UARTs.
686
687 CONFIG_PL01x_PORTS
688
689 If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
690 define this to a list of base addresses for each (supported)
691 port. See e.g. include/configs/versatile.h
692
Karicheri, Muralidharand57dee52014-04-09 15:38:46 -0400693 CONFIG_SERIAL_HW_FLOW_CONTROL
694
695 Define this variable to enable hw flow control in serial driver.
696 Current user of this option is drivers/serial/nsl16550.c driver
wdenk6705d812004-08-02 23:22:59 +0000697
wdenkc6097192002-11-03 00:24:07 +0000698- Console Baudrate:
699 CONFIG_BAUDRATE - in bps
700 Select one of the baudrates listed in
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +0200701 CONFIG_SYS_BAUDRATE_TABLE, see below.
wdenkc6097192002-11-03 00:24:07 +0000702
wdenkc6097192002-11-03 00:24:07 +0000703- Autoboot Command:
704 CONFIG_BOOTCOMMAND
705 Only needed when CONFIG_BOOTDELAY is enabled;
706 define a command string that is automatically executed
707 when no character is read on the console interface
708 within "Boot Delay" after reset.
709
wdenkc6097192002-11-03 00:24:07 +0000710 CONFIG_RAMBOOT and CONFIG_NFSBOOT
wdenk43d96162003-03-06 00:02:04 +0000711 The value of these goes into the environment as
712 "ramboot" and "nfsboot" respectively, and can be used
713 as a convenience, when switching between booting from
Marcel Ziswiler11ccc332008-07-09 08:17:15 +0200714 RAM and NFS.
wdenkc6097192002-11-03 00:24:07 +0000715
716- Pre-Boot Commands:
717 CONFIG_PREBOOT
718
719 When this option is #defined, the existence of the
720 environment variable "preboot" will be checked
721 immediately before starting the CONFIG_BOOTDELAY
722 countdown and/or running the auto-boot command resp.
723 entering interactive mode.
724
725 This feature is especially useful when "preboot" is
726 automatically generated or modified. For an example
727 see the LWMON board specific code: here "preboot" is
728 modified when the user holds down a certain
729 combination of keys on the (special) keyboard when
730 booting the systems
731
732- Serial Download Echo Mode:
733 CONFIG_LOADS_ECHO
734 If defined to 1, all characters received during a
735 serial download (using the "loads" command) are
736 echoed back. This might be needed by some terminal
737 emulations (like "cu"), but may as well just take
738 time on others. This setting #define's the initial
739 value of the "loads_echo" environment variable.
740
Jon Loeliger602ad3b2007-06-11 19:03:39 -0500741- Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined)
wdenkc6097192002-11-03 00:24:07 +0000742 CONFIG_KGDB_BAUDRATE
743 Select one of the baudrates listed in
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +0200744 CONFIG_SYS_BAUDRATE_TABLE, see below.
wdenkc6097192002-11-03 00:24:07 +0000745
Simon Glass302a6482016-03-13 19:07:28 -0600746- Removal of commands
747 If no commands are needed to boot, you can disable
748 CONFIG_CMDLINE to remove them. In this case, the command line
749 will not be available, and when U-Boot wants to execute the
750 boot command (on start-up) it will call board_run_command()
751 instead. This can reduce image size significantly for very
752 simple boot procedures.
753
Wolfgang Denka5ecbe62013-03-23 23:50:31 +0000754- Regular expression support:
755 CONFIG_REGEX
Wolfgang Denk93e14592013-10-04 17:43:24 +0200756 If this variable is defined, U-Boot is linked against
757 the SLRE (Super Light Regular Expression) library,
758 which adds regex support to some commands, as for
759 example "env grep" and "setexpr".
Wolfgang Denka5ecbe62013-03-23 23:50:31 +0000760
Simon Glass45ba8072011-10-15 05:48:20 +0000761- Device tree:
762 CONFIG_OF_CONTROL
763 If this variable is defined, U-Boot will use a device tree
764 to configure its devices, instead of relying on statically
765 compiled #defines in the board file. This option is
766 experimental and only available on a few boards. The device
767 tree is available in the global data as gd->fdt_blob.
768
Simon Glass2c0f79e2011-10-24 19:15:31 +0000769 U-Boot needs to get its device tree from somewhere. This can
Alex Deymo82f766d2017-04-02 01:25:20 -0700770 be done using one of the three options below:
Simon Glassbbb0b122011-10-15 05:48:21 +0000771
772 CONFIG_OF_EMBED
773 If this variable is defined, U-Boot will embed a device tree
774 binary in its image. This device tree file should be in the
775 board directory and called <soc>-<board>.dts. The binary file
776 is then picked up in board_init_f() and made available through
Nobuhiro Iwamatsueb3eb602017-08-26 07:34:14 +0900777 the global data structure as gd->fdt_blob.
Simon Glass45ba8072011-10-15 05:48:20 +0000778
Simon Glass2c0f79e2011-10-24 19:15:31 +0000779 CONFIG_OF_SEPARATE
780 If this variable is defined, U-Boot will build a device tree
781 binary. It will be called u-boot.dtb. Architecture-specific
782 code will locate it at run-time. Generally this works by:
783
784 cat u-boot.bin u-boot.dtb >image.bin
785
786 and in fact, U-Boot does this for you, creating a file called
787 u-boot-dtb.bin which is useful in the common case. You can
788 still use the individual files if you need something more
789 exotic.
790
Alex Deymo82f766d2017-04-02 01:25:20 -0700791 CONFIG_OF_BOARD
792 If this variable is defined, U-Boot will use the device tree
793 provided by the board at runtime instead of embedding one with
794 the image. Only boards defining board_fdt_blob_setup() support
795 this option (see include/fdtdec.h file).
796
wdenkc6097192002-11-03 00:24:07 +0000797- Watchdog:
798 CONFIG_WATCHDOG
799 If this variable is defined, it enables watchdog
Detlev Zundel6abe6fb2011-04-27 05:25:59 +0000800 support for the SoC. There must be support in the SoC
Christophe Leroy907208c2017-07-06 10:23:22 +0200801 specific code for a watchdog. For the 8xx
802 CPUs, the SIU Watchdog feature is enabled in the SYPCR
803 register. When supported for a specific SoC is
804 available, then no further board specific code should
805 be needed to use it.
Detlev Zundel6abe6fb2011-04-27 05:25:59 +0000806
807 CONFIG_HW_WATCHDOG
808 When using a watchdog circuitry external to the used
809 SoC, then define this variable and provide board
810 specific code for the "hw_watchdog_reset" function.
wdenkc6097192002-11-03 00:24:07 +0000811
Heiko Schocher7bae0d62015-01-21 08:38:22 +0100812 CONFIG_AT91_HW_WDT_TIMEOUT
813 specify the timeout in seconds. default 2 seconds.
814
stroesec1551ea2003-04-04 15:53:41 +0000815- U-Boot Version:
816 CONFIG_VERSION_VARIABLE
817 If this variable is defined, an environment variable
818 named "ver" is created by U-Boot showing the U-Boot
819 version as printed by the "version" command.
Benoît Thébaudeaua1ea8e52012-08-13 15:01:14 +0200820 Any change to this variable will be reverted at the
821 next reset.
stroesec1551ea2003-04-04 15:53:41 +0000822
wdenkc6097192002-11-03 00:24:07 +0000823- Real-Time Clock:
824
Jon Loeliger602ad3b2007-06-11 19:03:39 -0500825 When CONFIG_CMD_DATE is selected, the type of the RTC
wdenkc6097192002-11-03 00:24:07 +0000826 has to be selected, too. Define exactly one of the
827 following options:
828
wdenkc6097192002-11-03 00:24:07 +0000829 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
Fabio Estevam4e8b7542011-10-24 06:44:15 +0000830 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC
wdenkc6097192002-11-03 00:24:07 +0000831 CONFIG_RTC_MC146818 - use MC146818 RTC
wdenk1cb8e982003-03-06 21:55:29 +0000832 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
wdenkc6097192002-11-03 00:24:07 +0000833 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
wdenk7f70e852003-05-20 14:25:27 +0000834 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
Markus Niebel412921d2014-07-21 11:06:16 +0200835 CONFIG_RTC_DS1339 - use Maxim, Inc. DS1339 RTC
wdenk3bac3512003-03-12 10:41:04 +0000836 CONFIG_RTC_DS164x - use Dallas DS164x RTC
Tor Krill9536dfc2008-03-15 15:40:26 +0100837 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC
wdenk4c0d4c32004-06-09 17:34:58 +0000838 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
Chris Packham2bd3cab2017-05-30 12:03:33 +1200839 CONFIG_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337
Heiko Schocher71d19f32011-03-28 09:24:22 +0200840 CONFIG_SYS_RV3029_TCR - enable trickle charger on
841 RV3029 RTC.
wdenkc6097192002-11-03 00:24:07 +0000842
wdenkb37c7e52003-06-30 16:24:52 +0000843 Note that if the RTC uses I2C, then the I2C interface
844 must also be configured. See I2C Support, below.
845
Peter Tysere92739d2008-12-17 16:36:21 -0600846- GPIO Support:
847 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO
Peter Tysere92739d2008-12-17 16:36:21 -0600848
Chris Packham5dec49c2010-12-19 10:12:13 +0000849 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of
850 chip-ngpio pairs that tell the PCA953X driver the number of
851 pins supported by a particular chip.
852
Peter Tysere92739d2008-12-17 16:36:21 -0600853 Note that if the GPIO device uses I2C, then the I2C interface
854 must also be configured. See I2C Support, below.
855
Simon Glassaa532332014-06-11 23:29:41 -0600856- I/O tracing:
857 When CONFIG_IO_TRACE is selected, U-Boot intercepts all I/O
858 accesses and can checksum them or write a list of them out
859 to memory. See the 'iotrace' command for details. This is
860 useful for testing device drivers since it can confirm that
861 the driver behaves the same way before and after a code
862 change. Currently this is supported on sandbox and arm. To
863 add support for your architecture, add '#include <iotrace.h>'
864 to the bottom of arch/<arch>/include/asm/io.h and test.
865
866 Example output from the 'iotrace stats' command is below.
867 Note that if the trace buffer is exhausted, the checksum will
868 still continue to operate.
869
870 iotrace is enabled
871 Start: 10000000 (buffer start address)
872 Size: 00010000 (buffer size)
873 Offset: 00000120 (current buffer offset)
874 Output: 10000120 (start + offset)
875 Count: 00000018 (number of trace records)
876 CRC32: 9526fb66 (CRC32 of all trace records)
877
wdenkc6097192002-11-03 00:24:07 +0000878- Timestamp Support:
879
wdenk43d96162003-03-06 00:02:04 +0000880 When CONFIG_TIMESTAMP is selected, the timestamp
881 (date and time) of an image is printed by image
882 commands like bootm or iminfo. This option is
Jon Loeliger602ad3b2007-06-11 19:03:39 -0500883 automatically enabled when you select CONFIG_CMD_DATE .
wdenkc6097192002-11-03 00:24:07 +0000884
Karl O. Pinc923c46f2012-08-16 06:20:15 +0000885- Partition Labels (disklabels) Supported:
886 Zero or more of the following:
887 CONFIG_MAC_PARTITION Apple's MacOS partition table.
Karl O. Pinc923c46f2012-08-16 06:20:15 +0000888 CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc.
889 CONFIG_EFI_PARTITION GPT partition table, common when EFI is the
890 bootloader. Note 2TB partition limit; see
891 disk/part_efi.c
892 CONFIG_MTD_PARTITIONS Memory Technology Device partition table.
wdenkc6097192002-11-03 00:24:07 +0000893
Simon Glassfc843a02017-05-17 03:25:30 -0600894 If IDE or SCSI support is enabled (CONFIG_IDE or
Simon Glassc649e3c2016-05-01 11:36:02 -0600895 CONFIG_SCSI) you must configure support for at
Karl O. Pinc923c46f2012-08-16 06:20:15 +0000896 least one non-MTD partition type as well.
wdenkc6097192002-11-03 00:24:07 +0000897
898- IDE Reset method:
wdenk4d13cba2004-03-14 14:09:05 +0000899 CONFIG_IDE_RESET_ROUTINE - this is defined in several
900 board configurations files but used nowhere!
wdenkc6097192002-11-03 00:24:07 +0000901
wdenk4d13cba2004-03-14 14:09:05 +0000902 CONFIG_IDE_RESET - is this is defined, IDE Reset will
903 be performed by calling the function
904 ide_set_reset(int reset)
905 which has to be defined in a board specific file
wdenkc6097192002-11-03 00:24:07 +0000906
907- ATAPI Support:
908 CONFIG_ATAPI
909
910 Set this to enable ATAPI support.
911
wdenkc40b2952004-03-13 23:29:43 +0000912- LBA48 Support
913 CONFIG_LBA48
914
915 Set this to enable support for disks larger than 137GB
Heiko Schocher4b142fe2009-12-03 11:21:21 +0100916 Also look at CONFIG_SYS_64BIT_LBA.
wdenkc40b2952004-03-13 23:29:43 +0000917 Whithout these , LBA48 support uses 32bit variables and will 'only'
918 support disks up to 2.1TB.
919
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +0200920 CONFIG_SYS_64BIT_LBA:
wdenkc40b2952004-03-13 23:29:43 +0000921 When enabled, makes the IDE subsystem use 64bit sector addresses.
922 Default is 32bit.
923
wdenkc6097192002-11-03 00:24:07 +0000924- SCSI Support:
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +0200925 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and
926 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID *
927 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the
wdenkc6097192002-11-03 00:24:07 +0000928 maximum numbers of LUNs, SCSI ID's and target
929 devices.
wdenkc6097192002-11-03 00:24:07 +0000930
Wolfgang Denk93e14592013-10-04 17:43:24 +0200931 The environment variable 'scsidevs' is set to the number of
932 SCSI devices found during the last scan.
Stefan Reinauer447c0312012-10-29 05:23:48 +0000933
wdenkc6097192002-11-03 00:24:07 +0000934- NETWORK Support (PCI):
wdenk682011f2003-06-03 23:54:09 +0000935 CONFIG_E1000
Kyle Moffettce5207e2011-10-18 11:05:29 +0000936 Support for Intel 8254x/8257x gigabit chips.
937
938 CONFIG_E1000_SPI
939 Utility code for direct access to the SPI bus on Intel 8257x.
940 This does not do anything useful unless you set at least one
941 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC.
942
943 CONFIG_E1000_SPI_GENERIC
944 Allow generic access to the SPI bus on the Intel 8257x, for
945 example with the "sspi" command.
946
wdenkc6097192002-11-03 00:24:07 +0000947 CONFIG_EEPRO100
948 Support for Intel 82557/82559/82559ER chips.
Marcel Ziswiler11ccc332008-07-09 08:17:15 +0200949 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM
wdenkc6097192002-11-03 00:24:07 +0000950 write routine for first time initialisation.
951
952 CONFIG_TULIP
953 Support for Digital 2114x chips.
954 Optional CONFIG_TULIP_SELECT_MEDIA for board specific
955 modem chip initialisation (KS8761/QS6611).
956
957 CONFIG_NATSEMI
958 Support for National dp83815 chips.
959
960 CONFIG_NS8382X
961 Support for National dp8382[01] gigabit chips.
962
wdenk45219c42003-05-12 21:50:16 +0000963- NETWORK Support (other):
964
Jens Scharsigc041e9d2010-01-23 12:03:45 +0100965 CONFIG_DRIVER_AT91EMAC
966 Support for AT91RM9200 EMAC.
967
968 CONFIG_RMII
969 Define this to use reduced MII inteface
970
971 CONFIG_DRIVER_AT91EMAC_QUIET
972 If this defined, the driver is quiet.
973 The driver doen't show link status messages.
974
Rob Herringefdd7312011-12-15 11:15:49 +0000975 CONFIG_CALXEDA_XGMAC
976 Support for the Calxeda XGMAC device
977
Ashok3bb46d22012-10-15 06:20:47 +0000978 CONFIG_LAN91C96
wdenk45219c42003-05-12 21:50:16 +0000979 Support for SMSC's LAN91C96 chips.
980
wdenk45219c42003-05-12 21:50:16 +0000981 CONFIG_LAN91C96_USE_32_BIT
982 Define this to enable 32 bit addressing
983
Ashok3bb46d22012-10-15 06:20:47 +0000984 CONFIG_SMC91111
wdenkf39748a2004-06-09 13:37:52 +0000985 Support for SMSC's LAN91C111 chip
986
987 CONFIG_SMC91111_BASE
988 Define this to hold the physical address
989 of the device (I/O space)
990
991 CONFIG_SMC_USE_32_BIT
992 Define this if data bus is 32 bits
993
994 CONFIG_SMC_USE_IOFUNCS
995 Define this to use i/o functions instead of macros
996 (some hardware wont work with macros)
997
Heiko Schocherdc02bad2011-11-15 10:00:04 -0500998 CONFIG_DRIVER_TI_EMAC
999 Support for davinci emac
1000
1001 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT
1002 Define this if you have more then 3 PHYs.
1003
Macpaul Linb3dbf4a52010-12-21 16:59:46 +08001004 CONFIG_FTGMAC100
1005 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet
1006
1007 CONFIG_FTGMAC100_EGIGA
1008 Define this to use GE link update with gigabit PHY.
1009 Define this if FTGMAC100 is connected to gigabit PHY.
1010 If your system has 10/100 PHY only, it might not occur
1011 wrong behavior. Because PHY usually return timeout or
1012 useless data when polling gigabit status and gigabit
1013 control registers. This behavior won't affect the
1014 correctnessof 10/100 link speed update.
1015
Yoshihiro Shimoda3d0075f2011-01-27 10:06:03 +09001016 CONFIG_SH_ETHER
1017 Support for Renesas on-chip Ethernet controller
1018
1019 CONFIG_SH_ETHER_USE_PORT
1020 Define the number of ports to be used
1021
1022 CONFIG_SH_ETHER_PHY_ADDR
1023 Define the ETH PHY's address
1024
Yoshihiro Shimoda68260aa2011-01-27 10:06:08 +09001025 CONFIG_SH_ETHER_CACHE_WRITEBACK
1026 If this option is set, the driver enables cache flush.
1027
Heiko Schocherb2f97cf2014-07-18 06:07:19 +02001028- PWM Support:
1029 CONFIG_PWM_IMX
Robert P. J. Day5052e812016-09-13 08:35:18 -04001030 Support for PWM module on the imx6.
Heiko Schocherb2f97cf2014-07-18 06:07:19 +02001031
Vadim Bendebury5e124722011-10-17 08:36:14 +00001032- TPM Support:
Che-liang Chiou90899cc2013-04-12 11:04:34 +00001033 CONFIG_TPM
1034 Support TPM devices.
1035
Christophe Ricard0766ad22015-10-06 22:54:41 +02001036 CONFIG_TPM_TIS_INFINEON
1037 Support for Infineon i2c bus TPM devices. Only one device
Tom Wai-Hong Tam1b393db2013-04-12 11:04:37 +00001038 per system is supported at this time.
1039
Tom Wai-Hong Tam1b393db2013-04-12 11:04:37 +00001040 CONFIG_TPM_TIS_I2C_BURST_LIMITATION
1041 Define the burst count bytes upper limit
1042
Christophe Ricard3aa74082016-01-21 23:27:13 +01001043 CONFIG_TPM_ST33ZP24
1044 Support for STMicroelectronics TPM devices. Requires DM_TPM support.
1045
1046 CONFIG_TPM_ST33ZP24_I2C
1047 Support for STMicroelectronics ST33ZP24 I2C devices.
1048 Requires TPM_ST33ZP24 and I2C.
1049
Christophe Ricardb75fdc12016-01-21 23:27:14 +01001050 CONFIG_TPM_ST33ZP24_SPI
1051 Support for STMicroelectronics ST33ZP24 SPI devices.
1052 Requires TPM_ST33ZP24 and SPI.
1053
Dirk Eibachc01939c2013-06-26 15:55:15 +02001054 CONFIG_TPM_ATMEL_TWI
1055 Support for Atmel TWI TPM device. Requires I2C support.
1056
Che-liang Chiou90899cc2013-04-12 11:04:34 +00001057 CONFIG_TPM_TIS_LPC
Vadim Bendebury5e124722011-10-17 08:36:14 +00001058 Support for generic parallel port TPM devices. Only one device
1059 per system is supported at this time.
1060
1061 CONFIG_TPM_TIS_BASE_ADDRESS
1062 Base address where the generic TPM device is mapped
1063 to. Contemporary x86 systems usually map it at
1064 0xfed40000.
1065
Reinhard Pfaube6c1522013-06-26 15:55:13 +02001066 CONFIG_TPM
1067 Define this to enable the TPM support library which provides
1068 functional interfaces to some TPM commands.
1069 Requires support for a TPM device.
1070
1071 CONFIG_TPM_AUTH_SESSIONS
1072 Define this to enable authorized functions in the TPM library.
1073 Requires CONFIG_TPM and CONFIG_SHA1.
1074
wdenkc6097192002-11-03 00:24:07 +00001075- USB Support:
1076 At the moment only the UHCI host controller is
Heiko Schocher064b55c2017-06-14 05:49:40 +02001077 supported (PIP405, MIP405); define
wdenkc6097192002-11-03 00:24:07 +00001078 CONFIG_USB_UHCI to enable it.
1079 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
wdenk30d56fa2004-10-09 22:44:59 +00001080 and define CONFIG_USB_STORAGE to enable the USB
wdenkc6097192002-11-03 00:24:07 +00001081 storage devices.
1082 Note:
1083 Supported are USB Keyboards and USB Floppy drives
1084 (TEAC FD-05PUB).
wdenk4d13cba2004-03-14 14:09:05 +00001085
Simon Glass9ab4ce22012-02-27 10:52:47 +00001086 CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the
1087 txfilltuning field in the EHCI controller on reset.
1088
Oleksandr Tymoshenko6e9e0622014-02-01 21:51:25 -07001089 CONFIG_USB_DWC2_REG_ADDR the physical CPU address of the DWC2
1090 HW module registers.
1091
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +02001092- USB Device:
1093 Define the below if you wish to use the USB console.
1094 Once firmware is rebuilt from a serial console issue the
1095 command "setenv stdin usbtty; setenv stdout usbtty" and
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001096 attach your USB cable. The Unix command "dmesg" should print
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +02001097 it has found a new device. The environment variable usbtty
1098 can be set to gserial or cdc_acm to enable your device to
Wolfgang Denk386eda02006-06-14 18:14:56 +02001099 appear to a USB host as a Linux gserial device or a
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +02001100 Common Device Class Abstract Control Model serial device.
1101 If you select usbtty = gserial you should be able to enumerate
1102 a Linux host by
1103 # modprobe usbserial vendor=0xVendorID product=0xProductID
1104 else if using cdc_acm, simply setting the environment
1105 variable usbtty to be cdc_acm should suffice. The following
1106 might be defined in YourBoardName.h
Wolfgang Denk386eda02006-06-14 18:14:56 +02001107
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +02001108 CONFIG_USB_DEVICE
1109 Define this to build a UDC device
wdenkc6097192002-11-03 00:24:07 +00001110
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +02001111 CONFIG_USB_TTY
1112 Define this to have a tty type of device available to
1113 talk to the UDC device
Wolfgang Denk386eda02006-06-14 18:14:56 +02001114
Vipin KUMARf9da0f82012-03-26 15:38:06 +05301115 CONFIG_USBD_HS
1116 Define this to enable the high speed support for usb
1117 device and usbtty. If this feature is enabled, a routine
1118 int is_usbd_high_speed(void)
1119 also needs to be defined by the driver to dynamically poll
1120 whether the enumeration has succeded at high speed or full
1121 speed.
1122
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001123 CONFIG_SYS_CONSOLE_IS_IN_ENV
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +02001124 Define this if you want stdin, stdout &/or stderr to
1125 be set to usbtty.
1126
Wolfgang Denk386eda02006-06-14 18:14:56 +02001127 If you have a USB-IF assigned VendorID then you may wish to
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +02001128 define your own vendor specific values either in BoardName.h
Wolfgang Denk386eda02006-06-14 18:14:56 +02001129 or directly in usbd_vendor_info.h. If you don't define
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +02001130 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME,
1131 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot
1132 should pretend to be a Linux device to it's target host.
1133
1134 CONFIG_USBD_MANUFACTURER
1135 Define this string as the name of your company for
1136 - CONFIG_USBD_MANUFACTURER "my company"
Wolfgang Denk386eda02006-06-14 18:14:56 +02001137
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +02001138 CONFIG_USBD_PRODUCT_NAME
1139 Define this string as the name of your product
1140 - CONFIG_USBD_PRODUCT_NAME "acme usb device"
1141
1142 CONFIG_USBD_VENDORID
1143 Define this as your assigned Vendor ID from the USB
1144 Implementors Forum. This *must* be a genuine Vendor ID
1145 to avoid polluting the USB namespace.
1146 - CONFIG_USBD_VENDORID 0xFFFF
Wolfgang Denk386eda02006-06-14 18:14:56 +02001147
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +02001148 CONFIG_USBD_PRODUCTID
1149 Define this as the unique Product ID
1150 for your device
1151 - CONFIG_USBD_PRODUCTID 0xFFFF
wdenkc6097192002-11-03 00:24:07 +00001152
Igor Grinbergd70a5602011-12-12 12:08:35 +02001153- ULPI Layer Support:
1154 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via
1155 the generic ULPI layer. The generic layer accesses the ULPI PHY
1156 via the platform viewport, so you need both the genric layer and
1157 the viewport enabled. Currently only Chipidea/ARC based
1158 viewport is supported.
1159 To enable the ULPI layer support, define CONFIG_USB_ULPI and
1160 CONFIG_USB_ULPI_VIEWPORT in your board configuration file.
Lucas Stach6d365ea2012-10-01 00:44:35 +02001161 If your ULPI phy needs a different reference clock than the
1162 standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to
1163 the appropriate value in Hz.
wdenkc6097192002-11-03 00:24:07 +00001164
1165- MMC Support:
1166 The MMC controller on the Intel PXA is supported. To
1167 enable this define CONFIG_MMC. The MMC can be
1168 accessed from the boot prompt by mapping the device
1169 to physical memory similar to flash. Command line is
Jon Loeliger602ad3b2007-06-11 19:03:39 -05001170 enabled with CONFIG_CMD_MMC. The MMC driver also works with
1171 the FAT fs. This is enabled with CONFIG_CMD_FAT.
wdenkc6097192002-11-03 00:24:07 +00001172
Yoshihiro Shimodaafb35662011-07-04 22:21:22 +00001173 CONFIG_SH_MMCIF
1174 Support for Renesas on-chip MMCIF controller
1175
1176 CONFIG_SH_MMCIF_ADDR
1177 Define the base address of MMCIF registers
1178
1179 CONFIG_SH_MMCIF_CLK
1180 Define the clock frequency for MMCIF
1181
Pierre Aubert1fd93c62014-04-24 10:30:08 +02001182 CONFIG_SUPPORT_EMMC_BOOT
1183 Enable some additional features of the eMMC boot partitions.
1184
1185 CONFIG_SUPPORT_EMMC_RPMB
1186 Enable the commands for reading, writing and programming the
1187 key for the Replay Protection Memory Block partition in eMMC.
1188
Tom Rinib3ba6e92013-03-14 05:32:47 +00001189- USB Device Firmware Update (DFU) class support:
Marek Vasutbb4059a2018-02-16 16:41:18 +01001190 CONFIG_DFU_OVER_USB
Tom Rinib3ba6e92013-03-14 05:32:47 +00001191 This enables the USB portion of the DFU USB class
1192
Tom Rinib3ba6e92013-03-14 05:32:47 +00001193 CONFIG_DFU_MMC
1194 This enables support for exposing (e)MMC devices via DFU.
1195
Pantelis Antoniouc6631762013-03-14 05:32:52 +00001196 CONFIG_DFU_NAND
1197 This enables support for exposing NAND devices via DFU.
1198
Afzal Mohammeda9479f02013-09-18 01:15:24 +05301199 CONFIG_DFU_RAM
1200 This enables support for exposing RAM via DFU.
1201 Note: DFU spec refer to non-volatile memory usage, but
1202 allow usages beyond the scope of spec - here RAM usage,
1203 one that would help mostly the developer.
1204
Heiko Schochere7e75c72013-06-12 06:05:51 +02001205 CONFIG_SYS_DFU_DATA_BUF_SIZE
1206 Dfu transfer uses a buffer before writing data to the
1207 raw storage device. Make the size (in bytes) of this buffer
1208 configurable. The size of this buffer is also configurable
1209 through the "dfu_bufsiz" environment variable.
1210
Pantelis Antoniouea2453d2013-03-14 05:32:48 +00001211 CONFIG_SYS_DFU_MAX_FILE_SIZE
1212 When updating files rather than the raw storage device,
1213 we use a static buffer to copy the file into and then write
1214 the buffer once we've been given the whole file. Define
1215 this to the maximum filesize (in bytes) for the buffer.
1216 Default is 4 MiB if undefined.
1217
Heiko Schocher001a8312014-03-18 08:09:56 +01001218 DFU_DEFAULT_POLL_TIMEOUT
1219 Poll timeout [ms], is the timeout a device can send to the
1220 host. The host must wait for this timeout before sending
1221 a subsequent DFU_GET_STATUS request to the device.
1222
1223 DFU_MANIFEST_POLL_TIMEOUT
1224 Poll timeout [ms], which the device sends to the host when
1225 entering dfuMANIFEST state. Host waits this timeout, before
1226 sending again an USB request to the device.
1227
wdenk6705d812004-08-02 23:22:59 +00001228- Journaling Flash filesystem support:
Simon Glassb2482df2016-10-02 18:00:59 -06001229 CONFIG_JFFS2_NAND
wdenk6705d812004-08-02 23:22:59 +00001230 Define these for a default partition on a NAND device
1231
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001232 CONFIG_SYS_JFFS2_FIRST_SECTOR,
1233 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS
wdenk6705d812004-08-02 23:22:59 +00001234 Define these for a default partition on a NOR device
1235
wdenkc6097192002-11-03 00:24:07 +00001236- Keyboard Support:
Simon Glass39f615e2015-11-11 10:05:47 -07001237 See Kconfig help for available keyboard drivers.
1238
1239 CONFIG_KEYBOARD
1240
1241 Define this to enable a custom keyboard support.
1242 This simply calls drv_keyboard_init() which must be
1243 defined in your board-specific files. This option is deprecated
1244 and is only used by novena. For new boards, use driver model
1245 instead.
wdenkc6097192002-11-03 00:24:07 +00001246
1247- Video support:
Timur Tabi7d3053f2011-02-15 17:09:19 -06001248 CONFIG_FSL_DIU_FB
Wolfgang Denk04e5ae72011-09-11 21:24:09 +02001249 Enable the Freescale DIU video driver. Reference boards for
Timur Tabi7d3053f2011-02-15 17:09:19 -06001250 SOCs that have a DIU should define this macro to enable DIU
1251 support, and should also define these other macros:
1252
1253 CONFIG_SYS_DIU_ADDR
1254 CONFIG_VIDEO
Timur Tabi7d3053f2011-02-15 17:09:19 -06001255 CONFIG_CFB_CONSOLE
1256 CONFIG_VIDEO_SW_CURSOR
1257 CONFIG_VGA_AS_SINGLE_DEVICE
1258 CONFIG_VIDEO_LOGO
1259 CONFIG_VIDEO_BMP_LOGO
1260
Timur Tabiba8e76b2011-04-11 14:18:22 -05001261 The DIU driver will look for the 'video-mode' environment
1262 variable, and if defined, enable the DIU as a console during
Fabio Estevam8eca9432016-04-02 11:53:18 -03001263 boot. See the documentation file doc/README.video for a
Timur Tabiba8e76b2011-04-11 14:18:22 -05001264 description of this variable.
Timur Tabi7d3053f2011-02-15 17:09:19 -06001265
wdenkc6097192002-11-03 00:24:07 +00001266- LCD Support: CONFIG_LCD
1267
1268 Define this to enable LCD support (for output to LCD
1269 display); also select one of the supported displays
1270 by defining one of these:
1271
Stelian Pop39cf4802008-05-09 21:57:18 +02001272 CONFIG_ATMEL_LCD:
1273
1274 HITACHI TX09D70VM1CCA, 3.5", 240x320.
1275
wdenkfd3103b2003-11-25 16:55:19 +00001276 CONFIG_NEC_NL6448AC33:
wdenkc6097192002-11-03 00:24:07 +00001277
wdenkfd3103b2003-11-25 16:55:19 +00001278 NEC NL6448AC33-18. Active, color, single scan.
wdenkc6097192002-11-03 00:24:07 +00001279
wdenkfd3103b2003-11-25 16:55:19 +00001280 CONFIG_NEC_NL6448BC20
wdenkc6097192002-11-03 00:24:07 +00001281
wdenkfd3103b2003-11-25 16:55:19 +00001282 NEC NL6448BC20-08. 6.5", 640x480.
1283 Active, color, single scan.
1284
1285 CONFIG_NEC_NL6448BC33_54
1286
1287 NEC NL6448BC33-54. 10.4", 640x480.
wdenkc6097192002-11-03 00:24:07 +00001288 Active, color, single scan.
1289
1290 CONFIG_SHARP_16x9
1291
1292 Sharp 320x240. Active, color, single scan.
1293 It isn't 16x9, and I am not sure what it is.
1294
1295 CONFIG_SHARP_LQ64D341
1296
1297 Sharp LQ64D341 display, 640x480.
1298 Active, color, single scan.
1299
1300 CONFIG_HLD1045
1301
1302 HLD1045 display, 640x480.
1303 Active, color, single scan.
1304
1305 CONFIG_OPTREX_BW
1306
1307 Optrex CBL50840-2 NF-FW 99 22 M5
1308 or
1309 Hitachi LMG6912RPFC-00T
1310 or
1311 Hitachi SP14Q002
1312
1313 320x240. Black & white.
1314
Simon Glass676d3192012-10-17 13:24:54 +00001315 CONFIG_LCD_ALIGNMENT
1316
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08001317 Normally the LCD is page-aligned (typically 4KB). If this is
Simon Glass676d3192012-10-17 13:24:54 +00001318 defined then the LCD will be aligned to this value instead.
1319 For ARM it is sometimes useful to use MMU_SECTION_SIZE
1320 here, since it is cheaper to change data cache settings on
1321 a per-section basis.
1322
1323
Hannes Petermaier604c7d42015-03-27 08:01:38 +01001324 CONFIG_LCD_ROTATION
1325
1326 Sometimes, for example if the display is mounted in portrait
1327 mode or even if it's mounted landscape but rotated by 180degree,
1328 we need to rotate our content of the display relative to the
1329 framebuffer, so that user can read the messages which are
1330 printed out.
1331 Once CONFIG_LCD_ROTATION is defined, the lcd_console will be
1332 initialized with a given rotation from "vl_rot" out of
1333 "vidinfo_t" which is provided by the board specific code.
1334 The value for vl_rot is coded as following (matching to
1335 fbcon=rotate:<n> linux-kernel commandline):
1336 0 = no rotation respectively 0 degree
1337 1 = 90 degree rotation
1338 2 = 180 degree rotation
1339 3 = 270 degree rotation
1340
1341 If CONFIG_LCD_ROTATION is not defined, the console will be
1342 initialized with 0degree rotation.
1343
Tom Wai-Hong Tam45d7f522012-09-28 15:11:16 +00001344 CONFIG_LCD_BMP_RLE8
1345
1346 Support drawing of RLE8-compressed bitmaps on the LCD.
1347
Tom Wai-Hong Tam735987c2012-12-05 14:46:40 +00001348 CONFIG_I2C_EDID
1349
1350 Enables an 'i2c edid' command which can read EDID
1351 information over I2C from an attached LCD display.
1352
wdenk7152b1d2003-09-05 23:19:14 +00001353- Splash Screen Support: CONFIG_SPLASH_SCREEN
wdenkd791b1d2003-04-20 14:04:18 +00001354
wdenk8bde7f72003-06-27 21:31:46 +00001355 If this option is set, the environment is checked for
1356 a variable "splashimage". If found, the usual display
1357 of logo, copyright and system information on the LCD
wdenke94d2cd2004-06-30 22:59:18 +00001358 is suppressed and the BMP image at the address
wdenk8bde7f72003-06-27 21:31:46 +00001359 specified in "splashimage" is loaded instead. The
1360 console is redirected to the "nulldev", too. This
1361 allows for a "silent" boot where a splash screen is
1362 loaded very quickly after power-on.
wdenkd791b1d2003-04-20 14:04:18 +00001363
Nikita Kiryanovc0880482013-02-24 21:28:43 +00001364 CONFIG_SPLASHIMAGE_GUARD
1365
1366 If this option is set, then U-Boot will prevent the environment
1367 variable "splashimage" from being set to a problematic address
Fabio Estevamab5645f2016-03-23 12:46:12 -03001368 (see doc/README.displaying-bmps).
Nikita Kiryanovc0880482013-02-24 21:28:43 +00001369 This option is useful for targets where, due to alignment
1370 restrictions, an improperly aligned BMP image will cause a data
1371 abort. If you think you will not have problems with unaligned
1372 accesses (for example because your toolchain prevents them)
1373 there is no need to set this option.
1374
Matthias Weisser1ca298c2009-07-09 16:07:30 +02001375 CONFIG_SPLASH_SCREEN_ALIGN
1376
1377 If this option is set the splash image can be freely positioned
1378 on the screen. Environment variable "splashpos" specifies the
1379 position as "x,y". If a positive number is given it is used as
1380 number of pixel from left/top. If a negative number is given it
1381 is used as number of pixel from right/bottom. You can also
1382 specify 'm' for centering the image.
1383
1384 Example:
1385 setenv splashpos m,m
1386 => image at center of screen
1387
1388 setenv splashpos 30,20
1389 => image at x = 30 and y = 20
1390
1391 setenv splashpos -10,m
1392 => vertically centered image
1393 at x = dspWidth - bmpWidth - 9
1394
Stefan Roese98f4a3d2005-09-22 09:04:17 +02001395- Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
1396
1397 If this option is set, additionally to standard BMP
1398 images, gzipped BMP images can be displayed via the
1399 splashscreen support or the bmp command.
1400
Anatolij Gustschind5011762010-03-15 14:50:25 +01001401- Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8
1402
1403 If this option is set, 8-bit RLE compressed BMP images
1404 can be displayed via the splashscreen support or the
1405 bmp command.
1406
wdenkc29fdfc2003-08-29 20:57:53 +00001407- Compression support:
Kees Cook8ef70472013-08-16 07:59:12 -07001408 CONFIG_GZIP
1409
1410 Enabled by default to support gzip compressed images.
1411
wdenkc29fdfc2003-08-29 20:57:53 +00001412 CONFIG_BZIP2
1413
1414 If this option is set, support for bzip2 compressed
1415 images is included. If not, only uncompressed and gzip
1416 compressed images are supported.
1417
wdenk42d1f032003-10-15 23:53:47 +00001418 NOTE: the bzip2 algorithm requires a lot of RAM, so
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001419 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should
wdenk42d1f032003-10-15 23:53:47 +00001420 be at least 4MB.
wdenkd791b1d2003-04-20 14:04:18 +00001421
wdenk17ea1172004-06-06 21:51:03 +00001422- MII/PHY support:
1423 CONFIG_PHY_ADDR
1424
1425 The address of PHY on MII bus.
1426
1427 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
1428
1429 The clock frequency of the MII bus
1430
wdenk17ea1172004-06-06 21:51:03 +00001431 CONFIG_PHY_RESET_DELAY
1432
1433 Some PHY like Intel LXT971A need extra delay after
1434 reset before any MII register access is possible.
1435 For such PHY, set this option to the usec delay
1436 required. (minimum 300usec for LXT971A)
1437
1438 CONFIG_PHY_CMD_DELAY (ppc4xx)
1439
1440 Some PHY like Intel LXT971A need extra delay after
1441 command issued before MII status register can be read
1442
wdenkc6097192002-11-03 00:24:07 +00001443- IP address:
1444 CONFIG_IPADDR
1445
1446 Define a default value for the IP address to use for
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001447 the default Ethernet interface, in case this is not
wdenkc6097192002-11-03 00:24:07 +00001448 determined through e.g. bootp.
Wolfgang Denk1ebcd652011-10-26 10:21:22 +00001449 (Environment variable "ipaddr")
wdenkc6097192002-11-03 00:24:07 +00001450
1451- Server IP address:
1452 CONFIG_SERVERIP
1453
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001454 Defines a default value for the IP address of a TFTP
wdenkc6097192002-11-03 00:24:07 +00001455 server to contact when using the "tftboot" command.
Wolfgang Denk1ebcd652011-10-26 10:21:22 +00001456 (Environment variable "serverip")
wdenkc6097192002-11-03 00:24:07 +00001457
Robin Getz97cfe862009-07-21 12:15:28 -04001458 CONFIG_KEEP_SERVERADDR
1459
1460 Keeps the server's MAC address, in the env 'serveraddr'
1461 for passing to bootargs (like Linux's netconsole option)
1462
Wolfgang Denk1ebcd652011-10-26 10:21:22 +00001463- Gateway IP address:
1464 CONFIG_GATEWAYIP
1465
1466 Defines a default value for the IP address of the
1467 default router where packets to other networks are
1468 sent to.
1469 (Environment variable "gatewayip")
1470
1471- Subnet mask:
1472 CONFIG_NETMASK
1473
1474 Defines a default value for the subnet mask (or
1475 routing prefix) which is used to determine if an IP
1476 address belongs to the local subnet or needs to be
1477 forwarded through a router.
1478 (Environment variable "netmask")
1479
David Updegraff53a5c422007-06-11 10:41:07 -05001480- Multicast TFTP Mode:
1481 CONFIG_MCAST_TFTP
1482
1483 Defines whether you want to support multicast TFTP as per
1484 rfc-2090; for example to work with atftp. Lets lots of targets
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001485 tftp down the same boot image concurrently. Note: the Ethernet
David Updegraff53a5c422007-06-11 10:41:07 -05001486 driver in use must provide a function: mcast() to join/leave a
1487 multicast group.
1488
wdenkc6097192002-11-03 00:24:07 +00001489- BOOTP Recovery Mode:
1490 CONFIG_BOOTP_RANDOM_DELAY
1491
1492 If you have many targets in a network that try to
1493 boot using BOOTP, you may want to avoid that all
1494 systems send out BOOTP requests at precisely the same
1495 moment (which would happen for instance at recovery
1496 from a power failure, when all systems will try to
1497 boot, thus flooding the BOOTP server. Defining
1498 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
1499 inserted before sending out BOOTP requests. The
Wolfgang Denk6c33c782007-08-06 23:21:05 +02001500 following delays are inserted then:
wdenkc6097192002-11-03 00:24:07 +00001501
1502 1st BOOTP request: delay 0 ... 1 sec
1503 2nd BOOTP request: delay 0 ... 2 sec
1504 3rd BOOTP request: delay 0 ... 4 sec
1505 4th and following
1506 BOOTP requests: delay 0 ... 8 sec
1507
Thierry Reding92ac8ac2014-08-19 10:21:24 +02001508 CONFIG_BOOTP_ID_CACHE_SIZE
1509
1510 BOOTP packets are uniquely identified using a 32-bit ID. The
1511 server will copy the ID from client requests to responses and
1512 U-Boot will use this to determine if it is the destination of
1513 an incoming response. Some servers will check that addresses
1514 aren't in use before handing them out (usually using an ARP
1515 ping) and therefore take up to a few hundred milliseconds to
1516 respond. Network congestion may also influence the time it
1517 takes for a response to make it back to the client. If that
1518 time is too long, U-Boot will retransmit requests. In order
1519 to allow earlier responses to still be accepted after these
1520 retransmissions, U-Boot's BOOTP client keeps a small cache of
1521 IDs. The CONFIG_BOOTP_ID_CACHE_SIZE controls the size of this
1522 cache. The default is to keep IDs for up to four outstanding
1523 requests. Increasing this will allow U-Boot to accept offers
1524 from a BOOTP client in networks with unusually high latency.
1525
stroesefe389a82003-08-28 14:17:32 +00001526- DHCP Advanced Options:
Jon Loeliger1fe80d72007-07-09 22:08:34 -05001527 You can fine tune the DHCP functionality by defining
1528 CONFIG_BOOTP_* symbols:
stroesefe389a82003-08-28 14:17:32 +00001529
Jon Loeliger1fe80d72007-07-09 22:08:34 -05001530 CONFIG_BOOTP_NISDOMAIN
Jon Loeliger1fe80d72007-07-09 22:08:34 -05001531 CONFIG_BOOTP_BOOTFILESIZE
Jon Loeliger1fe80d72007-07-09 22:08:34 -05001532 CONFIG_BOOTP_SEND_HOSTNAME
1533 CONFIG_BOOTP_NTPSERVER
1534 CONFIG_BOOTP_TIMEOFFSET
1535 CONFIG_BOOTP_VENDOREX
Joe Hershberger2c00e092012-05-23 07:59:19 +00001536 CONFIG_BOOTP_MAY_FAIL
stroesefe389a82003-08-28 14:17:32 +00001537
Wilson Callan5d110f02007-07-28 10:56:13 -04001538 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip
1539 environment variable, not the BOOTP server.
stroesefe389a82003-08-28 14:17:32 +00001540
Joe Hershberger2c00e092012-05-23 07:59:19 +00001541 CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found
1542 after the configured retry count, the call will fail
1543 instead of starting over. This can be used to fail over
1544 to Link-local IP address configuration if the DHCP server
1545 is not available.
1546
stroesefe389a82003-08-28 14:17:32 +00001547 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
1548 to do a dynamic update of a DNS server. To do this, they
1549 need the hostname of the DHCP requester.
Wilson Callan5d110f02007-07-28 10:56:13 -04001550 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content
Jon Loeliger1fe80d72007-07-09 22:08:34 -05001551 of the "hostname" environment variable is passed as
1552 option 12 to the DHCP server.
stroesefe389a82003-08-28 14:17:32 +00001553
Aras Vaichasd9a2f412008-03-26 09:43:57 +11001554 CONFIG_BOOTP_DHCP_REQUEST_DELAY
1555
1556 A 32bit value in microseconds for a delay between
1557 receiving a "DHCP Offer" and sending the "DHCP Request".
1558 This fixes a problem with certain DHCP servers that don't
1559 respond 100% of the time to a "DHCP request". E.g. On an
1560 AT91RM9200 processor running at 180MHz, this delay needed
1561 to be *at least* 15,000 usec before a Windows Server 2003
1562 DHCP server would reply 100% of the time. I recommend at
1563 least 50,000 usec to be safe. The alternative is to hope
1564 that one of the retries will be successful but note that
1565 the DHCP timeout and retry process takes a longer than
1566 this delay.
1567
Joe Hershbergerd22c3382012-05-23 08:00:12 +00001568 - Link-local IP address negotiation:
1569 Negotiate with other link-local clients on the local network
1570 for an address that doesn't require explicit configuration.
1571 This is especially useful if a DHCP server cannot be guaranteed
1572 to exist in all environments that the device must operate.
1573
1574 See doc/README.link-local for more information.
1575
Prabhakar Kushwaha24acb832017-11-23 16:51:32 +05301576 - MAC address from environment variables
1577
1578 FDT_SEQ_MACADDR_FROM_ENV
1579
1580 Fix-up device tree with MAC addresses fetched sequentially from
1581 environment variables. This config work on assumption that
1582 non-usable ethernet node of device-tree are either not present
1583 or their status has been marked as "disabled".
1584
wdenka3d991b2004-04-15 21:48:45 +00001585 - CDP Options:
wdenk6e592382004-04-18 17:39:38 +00001586 CONFIG_CDP_DEVICE_ID
wdenka3d991b2004-04-15 21:48:45 +00001587
1588 The device id used in CDP trigger frames.
1589
1590 CONFIG_CDP_DEVICE_ID_PREFIX
1591
1592 A two character string which is prefixed to the MAC address
1593 of the device.
1594
1595 CONFIG_CDP_PORT_ID
1596
1597 A printf format string which contains the ascii name of
1598 the port. Normally is set to "eth%d" which sets
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001599 eth0 for the first Ethernet, eth1 for the second etc.
wdenka3d991b2004-04-15 21:48:45 +00001600
1601 CONFIG_CDP_CAPABILITIES
1602
1603 A 32bit integer which indicates the device capabilities;
1604 0x00000010 for a normal host which does not forwards.
1605
1606 CONFIG_CDP_VERSION
1607
1608 An ascii string containing the version of the software.
1609
1610 CONFIG_CDP_PLATFORM
1611
1612 An ascii string containing the name of the platform.
1613
1614 CONFIG_CDP_TRIGGER
1615
1616 A 32bit integer sent on the trigger.
1617
1618 CONFIG_CDP_POWER_CONSUMPTION
1619
1620 A 16bit integer containing the power consumption of the
1621 device in .1 of milliwatts.
1622
1623 CONFIG_CDP_APPLIANCE_VLAN_TYPE
1624
1625 A byte containing the id of the VLAN.
1626
Uri Mashiach79267ed2017-01-19 10:51:05 +02001627- Status LED: CONFIG_LED_STATUS
wdenkc6097192002-11-03 00:24:07 +00001628
1629 Several configurations allow to display the current
1630 status using a LED. For instance, the LED will blink
1631 fast while running U-Boot code, stop blinking as
1632 soon as a reply to a BOOTP request was received, and
1633 start blinking slow once the Linux kernel is running
1634 (supported by a status LED driver in the Linux
Uri Mashiach79267ed2017-01-19 10:51:05 +02001635 kernel). Defining CONFIG_LED_STATUS enables this
wdenkc6097192002-11-03 00:24:07 +00001636 feature in U-Boot.
1637
Igor Grinberg1df7bbb2013-11-08 01:03:50 +02001638 Additional options:
1639
Uri Mashiach79267ed2017-01-19 10:51:05 +02001640 CONFIG_LED_STATUS_GPIO
Igor Grinberg1df7bbb2013-11-08 01:03:50 +02001641 The status LED can be connected to a GPIO pin.
1642 In such cases, the gpio_led driver can be used as a
Uri Mashiach79267ed2017-01-19 10:51:05 +02001643 status LED backend implementation. Define CONFIG_LED_STATUS_GPIO
Igor Grinberg1df7bbb2013-11-08 01:03:50 +02001644 to include the gpio_led driver in the U-Boot binary.
1645
Igor Grinberg9dfdcdf2013-11-08 01:03:52 +02001646 CONFIG_GPIO_LED_INVERTED_TABLE
1647 Some GPIO connected LEDs may have inverted polarity in which
1648 case the GPIO high value corresponds to LED off state and
1649 GPIO low value corresponds to LED on state.
1650 In such cases CONFIG_GPIO_LED_INVERTED_TABLE may be defined
1651 with a list of GPIO LEDs that have inverted polarity.
1652
Heiko Schocher3f4978c2012-01-16 21:12:24 +00001653- I2C Support: CONFIG_SYS_I2C
wdenkc6097192002-11-03 00:24:07 +00001654
Heiko Schocher3f4978c2012-01-16 21:12:24 +00001655 This enable the NEW i2c subsystem, and will allow you to use
1656 i2c commands at the u-boot command line (as long as you set
1657 CONFIG_CMD_I2C in CONFIG_COMMANDS) and communicate with i2c
1658 based realtime clock chips or other i2c devices. See
1659 common/cmd_i2c.c for a description of the command line
1660 interface.
1661
1662 ported i2c driver to the new framework:
Heiko Schocherea818db2013-01-29 08:53:15 +01001663 - drivers/i2c/soft_i2c.c:
1664 - activate first bus with CONFIG_SYS_I2C_SOFT define
1665 CONFIG_SYS_I2C_SOFT_SPEED and CONFIG_SYS_I2C_SOFT_SLAVE
1666 for defining speed and slave address
1667 - activate second bus with I2C_SOFT_DECLARATIONS2 define
1668 CONFIG_SYS_I2C_SOFT_SPEED_2 and CONFIG_SYS_I2C_SOFT_SLAVE_2
1669 for defining speed and slave address
1670 - activate third bus with I2C_SOFT_DECLARATIONS3 define
1671 CONFIG_SYS_I2C_SOFT_SPEED_3 and CONFIG_SYS_I2C_SOFT_SLAVE_3
1672 for defining speed and slave address
1673 - activate fourth bus with I2C_SOFT_DECLARATIONS4 define
1674 CONFIG_SYS_I2C_SOFT_SPEED_4 and CONFIG_SYS_I2C_SOFT_SLAVE_4
1675 for defining speed and slave address
Heiko Schocher3f4978c2012-01-16 21:12:24 +00001676
Heiko Schocher00f792e2012-10-24 13:48:22 +02001677 - drivers/i2c/fsl_i2c.c:
1678 - activate i2c driver with CONFIG_SYS_I2C_FSL
1679 define CONFIG_SYS_FSL_I2C_OFFSET for setting the register
1680 offset CONFIG_SYS_FSL_I2C_SPEED for the i2c speed and
1681 CONFIG_SYS_FSL_I2C_SLAVE for the slave addr of the first
1682 bus.
Wolfgang Denk93e14592013-10-04 17:43:24 +02001683 - If your board supports a second fsl i2c bus, define
Heiko Schocher00f792e2012-10-24 13:48:22 +02001684 CONFIG_SYS_FSL_I2C2_OFFSET for the register offset
1685 CONFIG_SYS_FSL_I2C2_SPEED for the speed and
1686 CONFIG_SYS_FSL_I2C2_SLAVE for the slave address of the
1687 second bus.
1688
Simon Glass1f2ba722012-10-30 07:28:53 +00001689 - drivers/i2c/tegra_i2c.c:
Nobuhiro Iwamatsu10cee512013-10-11 16:23:53 +09001690 - activate this driver with CONFIG_SYS_I2C_TEGRA
1691 - This driver adds 4 i2c buses with a fix speed from
1692 100000 and the slave addr 0!
Simon Glass1f2ba722012-10-30 07:28:53 +00001693
Dirk Eibach880540d2013-04-25 02:40:01 +00001694 - drivers/i2c/ppc4xx_i2c.c
1695 - activate this driver with CONFIG_SYS_I2C_PPC4XX
1696 - CONFIG_SYS_I2C_PPC4XX_CH0 activate hardware channel 0
1697 - CONFIG_SYS_I2C_PPC4XX_CH1 activate hardware channel 1
1698
tremfac96402013-09-21 18:13:35 +02001699 - drivers/i2c/i2c_mxc.c
1700 - activate this driver with CONFIG_SYS_I2C_MXC
Albert ARIBAUD \\(3ADEV\\)03544c62015-09-21 22:43:38 +02001701 - enable bus 1 with CONFIG_SYS_I2C_MXC_I2C1
1702 - enable bus 2 with CONFIG_SYS_I2C_MXC_I2C2
1703 - enable bus 3 with CONFIG_SYS_I2C_MXC_I2C3
1704 - enable bus 4 with CONFIG_SYS_I2C_MXC_I2C4
tremfac96402013-09-21 18:13:35 +02001705 - define speed for bus 1 with CONFIG_SYS_MXC_I2C1_SPEED
1706 - define slave for bus 1 with CONFIG_SYS_MXC_I2C1_SLAVE
1707 - define speed for bus 2 with CONFIG_SYS_MXC_I2C2_SPEED
1708 - define slave for bus 2 with CONFIG_SYS_MXC_I2C2_SLAVE
1709 - define speed for bus 3 with CONFIG_SYS_MXC_I2C3_SPEED
1710 - define slave for bus 3 with CONFIG_SYS_MXC_I2C3_SLAVE
Albert ARIBAUD \\(3ADEV\\)03544c62015-09-21 22:43:38 +02001711 - define speed for bus 4 with CONFIG_SYS_MXC_I2C4_SPEED
1712 - define slave for bus 4 with CONFIG_SYS_MXC_I2C4_SLAVE
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08001713 If those defines are not set, default value is 100000
tremfac96402013-09-21 18:13:35 +02001714 for speed, and 0 for slave.
1715
Nobuhiro Iwamatsu1086bfa2013-09-27 16:58:30 +09001716 - drivers/i2c/rcar_i2c.c:
1717 - activate this driver with CONFIG_SYS_I2C_RCAR
1718 - This driver adds 4 i2c buses
1719
1720 - CONFIG_SYS_RCAR_I2C0_BASE for setting the register channel 0
1721 - CONFIG_SYS_RCAR_I2C0_SPEED for for the speed channel 0
1722 - CONFIG_SYS_RCAR_I2C1_BASE for setting the register channel 1
1723 - CONFIG_SYS_RCAR_I2C1_SPEED for for the speed channel 1
1724 - CONFIG_SYS_RCAR_I2C2_BASE for setting the register channel 2
1725 - CONFIG_SYS_RCAR_I2C2_SPEED for for the speed channel 2
1726 - CONFIG_SYS_RCAR_I2C3_BASE for setting the register channel 3
1727 - CONFIG_SYS_RCAR_I2C3_SPEED for for the speed channel 3
1728 - CONFIF_SYS_RCAR_I2C_NUM_CONTROLLERS for number of i2c buses
1729
Nobuhiro Iwamatsu2035d772013-10-29 13:33:51 +09001730 - drivers/i2c/sh_i2c.c:
1731 - activate this driver with CONFIG_SYS_I2C_SH
1732 - This driver adds from 2 to 5 i2c buses
1733
1734 - CONFIG_SYS_I2C_SH_BASE0 for setting the register channel 0
1735 - CONFIG_SYS_I2C_SH_SPEED0 for for the speed channel 0
1736 - CONFIG_SYS_I2C_SH_BASE1 for setting the register channel 1
1737 - CONFIG_SYS_I2C_SH_SPEED1 for for the speed channel 1
1738 - CONFIG_SYS_I2C_SH_BASE2 for setting the register channel 2
1739 - CONFIG_SYS_I2C_SH_SPEED2 for for the speed channel 2
1740 - CONFIG_SYS_I2C_SH_BASE3 for setting the register channel 3
1741 - CONFIG_SYS_I2C_SH_SPEED3 for for the speed channel 3
1742 - CONFIG_SYS_I2C_SH_BASE4 for setting the register channel 4
1743 - CONFIG_SYS_I2C_SH_SPEED4 for for the speed channel 4
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08001744 - CONFIG_SYS_I2C_SH_NUM_CONTROLLERS for number of i2c buses
Nobuhiro Iwamatsu2035d772013-10-29 13:33:51 +09001745
Heiko Schocher6789e842013-10-22 11:03:18 +02001746 - drivers/i2c/omap24xx_i2c.c
1747 - activate this driver with CONFIG_SYS_I2C_OMAP24XX
1748 - CONFIG_SYS_OMAP24_I2C_SPEED speed channel 0
1749 - CONFIG_SYS_OMAP24_I2C_SLAVE slave addr channel 0
1750 - CONFIG_SYS_OMAP24_I2C_SPEED1 speed channel 1
1751 - CONFIG_SYS_OMAP24_I2C_SLAVE1 slave addr channel 1
1752 - CONFIG_SYS_OMAP24_I2C_SPEED2 speed channel 2
1753 - CONFIG_SYS_OMAP24_I2C_SLAVE2 slave addr channel 2
1754 - CONFIG_SYS_OMAP24_I2C_SPEED3 speed channel 3
1755 - CONFIG_SYS_OMAP24_I2C_SLAVE3 slave addr channel 3
1756 - CONFIG_SYS_OMAP24_I2C_SPEED4 speed channel 4
1757 - CONFIG_SYS_OMAP24_I2C_SLAVE4 slave addr channel 4
1758
Heiko Schocher0bdffe72013-11-08 07:30:53 +01001759 - drivers/i2c/zynq_i2c.c
1760 - activate this driver with CONFIG_SYS_I2C_ZYNQ
1761 - set CONFIG_SYS_I2C_ZYNQ_SPEED for speed setting
1762 - set CONFIG_SYS_I2C_ZYNQ_SLAVE for slave addr
1763
Naveen Krishna Che717fc62013-12-06 12:12:38 +05301764 - drivers/i2c/s3c24x0_i2c.c:
1765 - activate this driver with CONFIG_SYS_I2C_S3C24X0
1766 - This driver adds i2c buses (11 for Exynos5250, Exynos5420
1767 9 i2c buses for Exynos4 and 1 for S3C24X0 SoCs from Samsung)
1768 with a fix speed from 100000 and the slave addr 0!
1769
Dirk Eibachb46226b2014-07-03 09:28:18 +02001770 - drivers/i2c/ihs_i2c.c
1771 - activate this driver with CONFIG_SYS_I2C_IHS
1772 - CONFIG_SYS_I2C_IHS_CH0 activate hardware channel 0
1773 - CONFIG_SYS_I2C_IHS_SPEED_0 speed channel 0
1774 - CONFIG_SYS_I2C_IHS_SLAVE_0 slave addr channel 0
1775 - CONFIG_SYS_I2C_IHS_CH1 activate hardware channel 1
1776 - CONFIG_SYS_I2C_IHS_SPEED_1 speed channel 1
1777 - CONFIG_SYS_I2C_IHS_SLAVE_1 slave addr channel 1
1778 - CONFIG_SYS_I2C_IHS_CH2 activate hardware channel 2
1779 - CONFIG_SYS_I2C_IHS_SPEED_2 speed channel 2
1780 - CONFIG_SYS_I2C_IHS_SLAVE_2 slave addr channel 2
1781 - CONFIG_SYS_I2C_IHS_CH3 activate hardware channel 3
1782 - CONFIG_SYS_I2C_IHS_SPEED_3 speed channel 3
1783 - CONFIG_SYS_I2C_IHS_SLAVE_3 slave addr channel 3
Dirk Eibach071be892015-10-28 11:46:22 +01001784 - activate dual channel with CONFIG_SYS_I2C_IHS_DUAL
1785 - CONFIG_SYS_I2C_IHS_SPEED_0_1 speed channel 0_1
1786 - CONFIG_SYS_I2C_IHS_SLAVE_0_1 slave addr channel 0_1
1787 - CONFIG_SYS_I2C_IHS_SPEED_1_1 speed channel 1_1
1788 - CONFIG_SYS_I2C_IHS_SLAVE_1_1 slave addr channel 1_1
1789 - CONFIG_SYS_I2C_IHS_SPEED_2_1 speed channel 2_1
1790 - CONFIG_SYS_I2C_IHS_SLAVE_2_1 slave addr channel 2_1
1791 - CONFIG_SYS_I2C_IHS_SPEED_3_1 speed channel 3_1
1792 - CONFIG_SYS_I2C_IHS_SLAVE_3_1 slave addr channel 3_1
Dirk Eibachb46226b2014-07-03 09:28:18 +02001793
Heiko Schocher3f4978c2012-01-16 21:12:24 +00001794 additional defines:
1795
1796 CONFIG_SYS_NUM_I2C_BUSES
Simon Glass945a18e2016-10-02 18:01:05 -06001797 Hold the number of i2c buses you want to use.
Heiko Schocher3f4978c2012-01-16 21:12:24 +00001798
1799 CONFIG_SYS_I2C_DIRECT_BUS
1800 define this, if you don't use i2c muxes on your hardware.
1801 if CONFIG_SYS_I2C_MAX_HOPS is not defined or == 0 you can
1802 omit this define.
1803
1804 CONFIG_SYS_I2C_MAX_HOPS
1805 define how many muxes are maximal consecutively connected
1806 on one i2c bus. If you not use i2c muxes, omit this
1807 define.
1808
1809 CONFIG_SYS_I2C_BUSES
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08001810 hold a list of buses you want to use, only used if
Heiko Schocher3f4978c2012-01-16 21:12:24 +00001811 CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example
1812 a board with CONFIG_SYS_I2C_MAX_HOPS = 1 and
1813 CONFIG_SYS_NUM_I2C_BUSES = 9:
1814
1815 CONFIG_SYS_I2C_BUSES {{0, {I2C_NULL_HOP}}, \
1816 {0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \
1817 {0, {{I2C_MUX_PCA9547, 0x70, 2}}}, \
1818 {0, {{I2C_MUX_PCA9547, 0x70, 3}}}, \
1819 {0, {{I2C_MUX_PCA9547, 0x70, 4}}}, \
1820 {0, {{I2C_MUX_PCA9547, 0x70, 5}}}, \
1821 {1, {I2C_NULL_HOP}}, \
1822 {1, {{I2C_MUX_PCA9544, 0x72, 1}}}, \
1823 {1, {{I2C_MUX_PCA9544, 0x72, 2}}}, \
1824 }
1825
1826 which defines
1827 bus 0 on adapter 0 without a mux
Heiko Schocherea818db2013-01-29 08:53:15 +01001828 bus 1 on adapter 0 with a PCA9547 on address 0x70 port 1
1829 bus 2 on adapter 0 with a PCA9547 on address 0x70 port 2
1830 bus 3 on adapter 0 with a PCA9547 on address 0x70 port 3
1831 bus 4 on adapter 0 with a PCA9547 on address 0x70 port 4
1832 bus 5 on adapter 0 with a PCA9547 on address 0x70 port 5
Heiko Schocher3f4978c2012-01-16 21:12:24 +00001833 bus 6 on adapter 1 without a mux
Heiko Schocherea818db2013-01-29 08:53:15 +01001834 bus 7 on adapter 1 with a PCA9544 on address 0x72 port 1
1835 bus 8 on adapter 1 with a PCA9544 on address 0x72 port 2
Heiko Schocher3f4978c2012-01-16 21:12:24 +00001836
1837 If you do not have i2c muxes on your board, omit this define.
1838
Simon Glassce3b5d62017-05-12 21:10:00 -06001839- Legacy I2C Support:
Heiko Schocherea818db2013-01-29 08:53:15 +01001840 If you use the software i2c interface (CONFIG_SYS_I2C_SOFT)
wdenkb37c7e52003-06-30 16:24:52 +00001841 then the following macros need to be defined (examples are
1842 from include/configs/lwmon.h):
wdenkc6097192002-11-03 00:24:07 +00001843
1844 I2C_INIT
1845
wdenkb37c7e52003-06-30 16:24:52 +00001846 (Optional). Any commands necessary to enable the I2C
wdenk43d96162003-03-06 00:02:04 +00001847 controller or configure ports.
wdenkc6097192002-11-03 00:24:07 +00001848
wdenkba56f622004-02-06 23:19:44 +00001849 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
wdenkb37c7e52003-06-30 16:24:52 +00001850
wdenkc6097192002-11-03 00:24:07 +00001851 I2C_ACTIVE
1852
1853 The code necessary to make the I2C data line active
1854 (driven). If the data line is open collector, this
1855 define can be null.
1856
wdenkb37c7e52003-06-30 16:24:52 +00001857 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
1858
wdenkc6097192002-11-03 00:24:07 +00001859 I2C_TRISTATE
1860
1861 The code necessary to make the I2C data line tri-stated
1862 (inactive). If the data line is open collector, this
1863 define can be null.
1864
wdenkb37c7e52003-06-30 16:24:52 +00001865 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
1866
wdenkc6097192002-11-03 00:24:07 +00001867 I2C_READ
1868
York Sun472d5462013-04-01 11:29:11 -07001869 Code that returns true if the I2C data line is high,
1870 false if it is low.
wdenkc6097192002-11-03 00:24:07 +00001871
wdenkb37c7e52003-06-30 16:24:52 +00001872 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
1873
wdenkc6097192002-11-03 00:24:07 +00001874 I2C_SDA(bit)
1875
York Sun472d5462013-04-01 11:29:11 -07001876 If <bit> is true, sets the I2C data line high. If it
1877 is false, it clears it (low).
wdenkc6097192002-11-03 00:24:07 +00001878
wdenkb37c7e52003-06-30 16:24:52 +00001879 eg: #define I2C_SDA(bit) \
wdenk2535d602003-07-17 23:16:40 +00001880 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
wdenkba56f622004-02-06 23:19:44 +00001881 else immr->im_cpm.cp_pbdat &= ~PB_SDA
wdenkb37c7e52003-06-30 16:24:52 +00001882
wdenkc6097192002-11-03 00:24:07 +00001883 I2C_SCL(bit)
1884
York Sun472d5462013-04-01 11:29:11 -07001885 If <bit> is true, sets the I2C clock line high. If it
1886 is false, it clears it (low).
wdenkc6097192002-11-03 00:24:07 +00001887
wdenkb37c7e52003-06-30 16:24:52 +00001888 eg: #define I2C_SCL(bit) \
wdenk2535d602003-07-17 23:16:40 +00001889 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
wdenkba56f622004-02-06 23:19:44 +00001890 else immr->im_cpm.cp_pbdat &= ~PB_SCL
wdenkb37c7e52003-06-30 16:24:52 +00001891
wdenkc6097192002-11-03 00:24:07 +00001892 I2C_DELAY
1893
1894 This delay is invoked four times per clock cycle so this
1895 controls the rate of data transfer. The data rate thus
wdenkb37c7e52003-06-30 16:24:52 +00001896 is 1 / (I2C_DELAY * 4). Often defined to be something
wdenk945af8d2003-07-16 21:53:01 +00001897 like:
1898
wdenkb37c7e52003-06-30 16:24:52 +00001899 #define I2C_DELAY udelay(2)
wdenkc6097192002-11-03 00:24:07 +00001900
Mike Frysinger793b5722010-07-21 13:38:02 -04001901 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA
1902
1903 If your arch supports the generic GPIO framework (asm/gpio.h),
1904 then you may alternatively define the two GPIOs that are to be
1905 used as SCL / SDA. Any of the previous I2C_xxx macros will
1906 have GPIO-based defaults assigned to them as appropriate.
1907
1908 You should define these to the GPIO value as given directly to
1909 the generic GPIO functions.
1910
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001911 CONFIG_SYS_I2C_INIT_BOARD
wdenk47cd00f2003-03-06 13:39:27 +00001912
wdenk8bde7f72003-06-27 21:31:46 +00001913 When a board is reset during an i2c bus transfer
1914 chips might think that the current transfer is still
1915 in progress. On some boards it is possible to access
1916 the i2c SCLK line directly, either by using the
1917 processor pin as a GPIO or by having a second pin
1918 connected to the bus. If this option is defined a
1919 custom i2c_init_board() routine in boards/xxx/board.c
1920 is run early in the boot sequence.
wdenk47cd00f2003-03-06 13:39:27 +00001921
Ben Warrenbb99ad62006-09-07 16:50:54 -04001922 CONFIG_I2C_MULTI_BUS
1923
1924 This option allows the use of multiple I2C buses, each of which
Wolfgang Denkc0f40852011-10-26 10:21:21 +00001925 must have a controller. At any point in time, only one bus is
1926 active. To switch to a different bus, use the 'i2c dev' command.
Ben Warrenbb99ad62006-09-07 16:50:54 -04001927 Note that bus numbering is zero-based.
1928
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001929 CONFIG_SYS_I2C_NOPROBES
Ben Warrenbb99ad62006-09-07 16:50:54 -04001930
1931 This option specifies a list of I2C devices that will be skipped
Wolfgang Denkc0f40852011-10-26 10:21:21 +00001932 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS
Peter Tyser0f89c542009-04-18 22:34:03 -05001933 is set, specify a list of bus-device pairs. Otherwise, specify
1934 a 1D array of device addresses
Ben Warrenbb99ad62006-09-07 16:50:54 -04001935
1936 e.g.
1937 #undef CONFIG_I2C_MULTI_BUS
Wolfgang Denkc0f40852011-10-26 10:21:21 +00001938 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68}
Ben Warrenbb99ad62006-09-07 16:50:54 -04001939
1940 will skip addresses 0x50 and 0x68 on a board with one I2C bus
1941
Wolfgang Denkc0f40852011-10-26 10:21:21 +00001942 #define CONFIG_I2C_MULTI_BUS
Simon Glass945a18e2016-10-02 18:01:05 -06001943 #define CONFIG_SYS_I2C_NOPROBES {{0,0x50},{0,0x68},{1,0x54}}
Ben Warrenbb99ad62006-09-07 16:50:54 -04001944
1945 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1
1946
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001947 CONFIG_SYS_SPD_BUS_NUM
Timur Tabibe5e6182006-11-03 19:15:00 -06001948
1949 If defined, then this indicates the I2C bus number for DDR SPD.
1950 If not defined, then U-Boot assumes that SPD is on I2C bus 0.
1951
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001952 CONFIG_SYS_RTC_BUS_NUM
Stefan Roese0dc018e2007-02-20 10:51:26 +01001953
1954 If defined, then this indicates the I2C bus number for the RTC.
1955 If not defined, then U-Boot assumes that RTC is on I2C bus 0.
1956
Andrew Dyer2ac69852008-12-29 17:36:01 -06001957 CONFIG_SOFT_I2C_READ_REPEATED_START
1958
1959 defining this will force the i2c_read() function in
1960 the soft_i2c driver to perform an I2C repeated start
1961 between writing the address pointer and reading the
1962 data. If this define is omitted the default behaviour
1963 of doing a stop-start sequence will be used. Most I2C
1964 devices can use either method, but some require one or
1965 the other.
Timur Tabibe5e6182006-11-03 19:15:00 -06001966
wdenkc6097192002-11-03 00:24:07 +00001967- SPI Support: CONFIG_SPI
1968
1969 Enables SPI driver (so far only tested with
1970 SPI EEPROM, also an instance works with Crystal A/D and
1971 D/As on the SACSng board)
1972
wdenkc6097192002-11-03 00:24:07 +00001973 CONFIG_SOFT_SPI
1974
wdenk43d96162003-03-06 00:02:04 +00001975 Enables a software (bit-bang) SPI driver rather than
1976 using hardware support. This is a general purpose
1977 driver that only requires three general I/O port pins
1978 (two outputs, one input) to function. If this is
1979 defined, the board configuration must define several
1980 SPI configuration items (port pins to use, etc). For
1981 an example, see include/configs/sacsng.h.
wdenkc6097192002-11-03 00:24:07 +00001982
Ben Warren04a9e112008-01-16 22:37:35 -05001983 CONFIG_HARD_SPI
1984
1985 Enables a hardware SPI driver for general-purpose reads
1986 and writes. As with CONFIG_SOFT_SPI, the board configuration
1987 must define a list of chip-select function pointers.
Wolfgang Denkc0f40852011-10-26 10:21:21 +00001988 Currently supported on some MPC8xxx processors. For an
Ben Warren04a9e112008-01-16 22:37:35 -05001989 example, see include/configs/mpc8349emds.h.
1990
Heiko Schocherf659b572014-07-14 10:22:11 +02001991 CONFIG_SYS_SPI_MXC_WAIT
1992 Timeout for waiting until spi transfer completed.
1993 default: (CONFIG_SYS_HZ/100) /* 10 ms */
1994
Matthias Fuchs01335022007-12-27 17:12:34 +01001995- FPGA Support: CONFIG_FPGA
1996
1997 Enables FPGA subsystem.
1998
1999 CONFIG_FPGA_<vendor>
2000
2001 Enables support for specific chip vendors.
2002 (ALTERA, XILINX)
2003
2004 CONFIG_FPGA_<family>
2005
2006 Enables support for FPGA family.
2007 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
2008
2009 CONFIG_FPGA_COUNT
wdenkc6097192002-11-03 00:24:07 +00002010
wdenk43d96162003-03-06 00:02:04 +00002011 Specify the number of FPGA devices to support.
wdenkc6097192002-11-03 00:24:07 +00002012
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002013 CONFIG_SYS_FPGA_PROG_FEEDBACK
wdenkc6097192002-11-03 00:24:07 +00002014
wdenk8bde7f72003-06-27 21:31:46 +00002015 Enable printing of hash marks during FPGA configuration.
wdenkc6097192002-11-03 00:24:07 +00002016
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002017 CONFIG_SYS_FPGA_CHECK_BUSY
wdenkc6097192002-11-03 00:24:07 +00002018
wdenk43d96162003-03-06 00:02:04 +00002019 Enable checks on FPGA configuration interface busy
2020 status by the configuration function. This option
2021 will require a board or device specific function to
2022 be written.
wdenkc6097192002-11-03 00:24:07 +00002023
2024 CONFIG_FPGA_DELAY
2025
2026 If defined, a function that provides delays in the FPGA
2027 configuration driver.
2028
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002029 CONFIG_SYS_FPGA_CHECK_CTRLC
wdenkc6097192002-11-03 00:24:07 +00002030 Allow Control-C to interrupt FPGA configuration
2031
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002032 CONFIG_SYS_FPGA_CHECK_ERROR
wdenkc6097192002-11-03 00:24:07 +00002033
wdenk43d96162003-03-06 00:02:04 +00002034 Check for configuration errors during FPGA bitfile
2035 loading. For example, abort during Virtex II
2036 configuration if the INIT_B line goes low (which
2037 indicated a CRC error).
wdenkc6097192002-11-03 00:24:07 +00002038
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002039 CONFIG_SYS_FPGA_WAIT_INIT
wdenkc6097192002-11-03 00:24:07 +00002040
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08002041 Maximum time to wait for the INIT_B line to de-assert
2042 after PROB_B has been de-asserted during a Virtex II
wdenk43d96162003-03-06 00:02:04 +00002043 FPGA configuration sequence. The default time is 500
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002044 ms.
wdenkc6097192002-11-03 00:24:07 +00002045
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002046 CONFIG_SYS_FPGA_WAIT_BUSY
wdenkc6097192002-11-03 00:24:07 +00002047
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08002048 Maximum time to wait for BUSY to de-assert during
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002049 Virtex II FPGA configuration. The default is 5 ms.
wdenkc6097192002-11-03 00:24:07 +00002050
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002051 CONFIG_SYS_FPGA_WAIT_CONFIG
wdenkc6097192002-11-03 00:24:07 +00002052
wdenk43d96162003-03-06 00:02:04 +00002053 Time to wait after FPGA configuration. The default is
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002054 200 ms.
wdenkc6097192002-11-03 00:24:07 +00002055
2056- Configuration Management:
Stefan Roeseb2b8a692014-10-22 12:13:24 +02002057 CONFIG_BUILD_TARGET
2058
2059 Some SoCs need special image types (e.g. U-Boot binary
2060 with a special header) as build targets. By defining
2061 CONFIG_BUILD_TARGET in the SoC / board header, this
2062 special image will be automatically built upon calling
Simon Glass6de80f22016-07-27 20:33:08 -06002063 make / buildman.
Stefan Roeseb2b8a692014-10-22 12:13:24 +02002064
wdenkc6097192002-11-03 00:24:07 +00002065 CONFIG_IDENT_STRING
2066
wdenk43d96162003-03-06 00:02:04 +00002067 If defined, this string will be added to the U-Boot
2068 version information (U_BOOT_VERSION)
wdenkc6097192002-11-03 00:24:07 +00002069
2070- Vendor Parameter Protection:
2071
wdenk43d96162003-03-06 00:02:04 +00002072 U-Boot considers the values of the environment
2073 variables "serial#" (Board Serial Number) and
wdenk7152b1d2003-09-05 23:19:14 +00002074 "ethaddr" (Ethernet Address) to be parameters that
wdenk43d96162003-03-06 00:02:04 +00002075 are set once by the board vendor / manufacturer, and
2076 protects these variables from casual modification by
2077 the user. Once set, these variables are read-only,
2078 and write or delete attempts are rejected. You can
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002079 change this behaviour:
wdenkc6097192002-11-03 00:24:07 +00002080
2081 If CONFIG_ENV_OVERWRITE is #defined in your config
2082 file, the write protection for vendor parameters is
wdenk47cd00f2003-03-06 13:39:27 +00002083 completely disabled. Anybody can change or delete
wdenkc6097192002-11-03 00:24:07 +00002084 these parameters.
2085
Joe Hershberger92ac5202015-05-04 14:55:14 -05002086 Alternatively, if you define _both_ an ethaddr in the
2087 default env _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002088 Ethernet address is installed in the environment,
wdenkc6097192002-11-03 00:24:07 +00002089 which can be changed exactly ONCE by the user. [The
2090 serial# is unaffected by this, i. e. it remains
2091 read-only.]
2092
Joe Hershberger25980902012-12-11 22:16:31 -06002093 The same can be accomplished in a more flexible way
2094 for any variable by configuring the type of access
2095 to allow for those variables in the ".flags" variable
2096 or define CONFIG_ENV_FLAGS_LIST_STATIC.
2097
wdenkc6097192002-11-03 00:24:07 +00002098- Protected RAM:
2099 CONFIG_PRAM
2100
2101 Define this variable to enable the reservation of
2102 "protected RAM", i. e. RAM which is not overwritten
2103 by U-Boot. Define CONFIG_PRAM to hold the number of
2104 kB you want to reserve for pRAM. You can overwrite
2105 this default value by defining an environment
2106 variable "pram" to the number of kB you want to
2107 reserve. Note that the board info structure will
2108 still show the full amount of RAM. If pRAM is
2109 reserved, a new environment variable "mem" will
2110 automatically be defined to hold the amount of
2111 remaining RAM in a form that can be passed as boot
2112 argument to Linux, for instance like that:
2113
Wolfgang Denkfe126d82005-11-20 21:40:11 +01002114 setenv bootargs ... mem=\${mem}
wdenkc6097192002-11-03 00:24:07 +00002115 saveenv
2116
2117 This way you can tell Linux not to use this memory,
2118 either, which results in a memory region that will
2119 not be affected by reboots.
2120
2121 *WARNING* If your board configuration uses automatic
2122 detection of the RAM size, you must make sure that
2123 this memory test is non-destructive. So far, the
2124 following board configurations are known to be
2125 "pRAM-clean":
2126
Heiko Schocher5b8e76c2017-06-07 17:33:09 +02002127 IVMS8, IVML24, SPD8xx,
Wolfgang Denk1b0757e2012-10-24 02:36:15 +00002128 HERMES, IP860, RPXlite, LWMON,
Heiko Schocher2eb48ff2017-06-07 17:33:10 +02002129 FLAGADM
wdenkc6097192002-11-03 00:24:07 +00002130
Gabe Black40fef042012-12-02 04:55:18 +00002131- Access to physical memory region (> 4GB)
2132 Some basic support is provided for operations on memory not
2133 normally accessible to U-Boot - e.g. some architectures
2134 support access to more than 4GB of memory on 32-bit
2135 machines using physical address extension or similar.
2136 Define CONFIG_PHYSMEM to access this basic support, which
2137 currently only supports clearing the memory.
2138
wdenkc6097192002-11-03 00:24:07 +00002139- Error Recovery:
wdenkc6097192002-11-03 00:24:07 +00002140 CONFIG_NET_RETRY_COUNT
2141
wdenk43d96162003-03-06 00:02:04 +00002142 This variable defines the number of retries for
2143 network operations like ARP, RARP, TFTP, or BOOTP
2144 before giving up the operation. If not defined, a
2145 default value of 5 is used.
wdenkc6097192002-11-03 00:24:07 +00002146
Guennadi Liakhovetski40cb90e2008-04-03 17:04:19 +02002147 CONFIG_ARP_TIMEOUT
2148
2149 Timeout waiting for an ARP reply in milliseconds.
2150
Tetsuyuki Kobayashi48a3e992012-07-03 22:25:21 +00002151 CONFIG_NFS_TIMEOUT
2152
2153 Timeout in milliseconds used in NFS protocol.
2154 If you encounter "ERROR: Cannot umount" in nfs command,
2155 try longer timeout such as
2156 #define CONFIG_NFS_TIMEOUT 10000UL
2157
wdenkc6097192002-11-03 00:24:07 +00002158- Command Interpreter:
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002159 CONFIG_SYS_PROMPT_HUSH_PS2
wdenkc6097192002-11-03 00:24:07 +00002160
2161 This defines the secondary prompt string, which is
2162 printed when the command interpreter needs more input
2163 to complete a command. Usually "> ".
2164
2165 Note:
2166
wdenk8bde7f72003-06-27 21:31:46 +00002167 In the current implementation, the local variables
2168 space and global environment variables space are
2169 separated. Local variables are those you define by
2170 simply typing `name=value'. To access a local
2171 variable later on, you have write `$name' or
2172 `${name}'; to execute the contents of a variable
2173 directly type `$name' at the command prompt.
wdenkc6097192002-11-03 00:24:07 +00002174
wdenk43d96162003-03-06 00:02:04 +00002175 Global environment variables are those you use
2176 setenv/printenv to work with. To run a command stored
2177 in such a variable, you need to use the run command,
2178 and you must not use the '$' sign to access them.
wdenkc6097192002-11-03 00:24:07 +00002179
2180 To store commands and special characters in a
2181 variable, please use double quotation marks
2182 surrounding the whole text of the variable, instead
2183 of the backslashes before semicolons and special
2184 symbols.
2185
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08002186- Command Line Editing and History:
Marek Vasutf3b267b2016-01-27 04:47:55 +01002187 CONFIG_CMDLINE_PS_SUPPORT
2188
2189 Enable support for changing the command prompt string
2190 at run-time. Only static string is supported so far.
2191 The string is obtained from environment variables PS1
2192 and PS2.
2193
wdenka8c7c702003-12-06 19:49:23 +00002194- Default Environment:
wdenkc6097192002-11-03 00:24:07 +00002195 CONFIG_EXTRA_ENV_SETTINGS
2196
wdenk43d96162003-03-06 00:02:04 +00002197 Define this to contain any number of null terminated
2198 strings (variable = value pairs) that will be part of
wdenk7152b1d2003-09-05 23:19:14 +00002199 the default environment compiled into the boot image.
wdenk2262cfe2002-11-18 00:14:45 +00002200
wdenk43d96162003-03-06 00:02:04 +00002201 For example, place something like this in your
2202 board's config file:
wdenkc6097192002-11-03 00:24:07 +00002203
2204 #define CONFIG_EXTRA_ENV_SETTINGS \
2205 "myvar1=value1\0" \
2206 "myvar2=value2\0"
2207
wdenk43d96162003-03-06 00:02:04 +00002208 Warning: This method is based on knowledge about the
2209 internal format how the environment is stored by the
2210 U-Boot code. This is NOT an official, exported
2211 interface! Although it is unlikely that this format
wdenk7152b1d2003-09-05 23:19:14 +00002212 will change soon, there is no guarantee either.
wdenkc6097192002-11-03 00:24:07 +00002213 You better know what you are doing here.
2214
wdenk43d96162003-03-06 00:02:04 +00002215 Note: overly (ab)use of the default environment is
2216 discouraged. Make sure to check other ways to preset
Wolfgang Denk74de7ae2009-04-01 23:34:12 +02002217 the environment like the "source" command or the
wdenk43d96162003-03-06 00:02:04 +00002218 boot command first.
wdenkc6097192002-11-03 00:24:07 +00002219
Tom Rini7e27f892012-10-24 07:28:16 +00002220 CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG
2221
2222 Define this in order to add variables describing certain
2223 run-time determined information about the hardware to the
2224 environment. These will be named board_name, board_rev.
2225
Simon Glass06fd8532012-11-30 13:01:17 +00002226 CONFIG_DELAY_ENVIRONMENT
2227
2228 Normally the environment is loaded when the board is
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08002229 initialised so that it is available to U-Boot. This inhibits
Simon Glass06fd8532012-11-30 13:01:17 +00002230 that so that the environment is not available until
2231 explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL
2232 this is instead controlled by the value of
2233 /config/load-environment.
2234
Eric Nelsonf61ec452012-01-31 10:52:08 -07002235- Serial Flash support
Simon Glass00fd59d2017-08-04 16:35:06 -06002236 Usage requires an initial 'sf probe' to define the serial
Eric Nelsonf61ec452012-01-31 10:52:08 -07002237 flash parameters, followed by read/write/erase/update
2238 commands.
2239
2240 The following defaults may be provided by the platform
2241 to handle the common case when only a single serial
2242 flash is present on the system.
2243
2244 CONFIG_SF_DEFAULT_BUS Bus identifier
2245 CONFIG_SF_DEFAULT_CS Chip-select
2246 CONFIG_SF_DEFAULT_MODE (see include/spi.h)
2247 CONFIG_SF_DEFAULT_SPEED in Hz
2248
wdenk3f85ce22004-02-23 16:11:30 +00002249
Wolfgang Denkecb0ccd2005-09-24 22:37:32 +02002250- TFTP Fixed UDP Port:
2251 CONFIG_TFTP_PORT
2252
Wolfgang Denk28cb9372005-09-24 23:25:46 +02002253 If this is defined, the environment variable tftpsrcp
Wolfgang Denkecb0ccd2005-09-24 22:37:32 +02002254 is used to supply the TFTP UDP source port value.
Wolfgang Denk28cb9372005-09-24 23:25:46 +02002255 If tftpsrcp isn't defined, the normal pseudo-random port
Wolfgang Denkecb0ccd2005-09-24 22:37:32 +02002256 number generator is used.
2257
Wolfgang Denk28cb9372005-09-24 23:25:46 +02002258 Also, the environment variable tftpdstp is used to supply
2259 the TFTP UDP destination port value. If tftpdstp isn't
2260 defined, the normal port 69 is used.
2261
2262 The purpose for tftpsrcp is to allow a TFTP server to
Wolfgang Denkecb0ccd2005-09-24 22:37:32 +02002263 blindly start the TFTP transfer using the pre-configured
2264 target IP address and UDP port. This has the effect of
2265 "punching through" the (Windows XP) firewall, allowing
2266 the remainder of the TFTP transfer to proceed normally.
2267 A better solution is to properly configure the firewall,
2268 but sometimes that is not allowed.
2269
wdenka8c7c702003-12-06 19:49:23 +00002270- Show boot progress:
wdenkc6097192002-11-03 00:24:07 +00002271 CONFIG_SHOW_BOOT_PROGRESS
2272
wdenk43d96162003-03-06 00:02:04 +00002273 Defining this option allows to add some board-
2274 specific code (calling a user-provided function
2275 "show_boot_progress(int)") that enables you to show
2276 the system's boot progress on some display (for
2277 example, some LED's) on your board. At the moment,
2278 the following checkpoints are implemented:
wdenkc6097192002-11-03 00:24:07 +00002279
Simon Glass94fd1312012-09-28 08:56:37 +00002280
Marian Balakowicz1372cce2008-03-12 10:33:01 +01002281Legacy uImage format:
2282
wdenkc6097192002-11-03 00:24:07 +00002283 Arg Where When
2284 1 common/cmd_bootm.c before attempting to boot an image
wdenkba56f622004-02-06 23:19:44 +00002285 -1 common/cmd_bootm.c Image header has bad magic number
wdenkc6097192002-11-03 00:24:07 +00002286 2 common/cmd_bootm.c Image header has correct magic number
wdenkba56f622004-02-06 23:19:44 +00002287 -2 common/cmd_bootm.c Image header has bad checksum
wdenkc6097192002-11-03 00:24:07 +00002288 3 common/cmd_bootm.c Image header has correct checksum
wdenkba56f622004-02-06 23:19:44 +00002289 -3 common/cmd_bootm.c Image data has bad checksum
wdenkc6097192002-11-03 00:24:07 +00002290 4 common/cmd_bootm.c Image data has correct checksum
2291 -4 common/cmd_bootm.c Image is for unsupported architecture
2292 5 common/cmd_bootm.c Architecture check OK
Marian Balakowicz1372cce2008-03-12 10:33:01 +01002293 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi)
wdenkc6097192002-11-03 00:24:07 +00002294 6 common/cmd_bootm.c Image Type check OK
2295 -6 common/cmd_bootm.c gunzip uncompression error
2296 -7 common/cmd_bootm.c Unimplemented compression type
2297 7 common/cmd_bootm.c Uncompression OK
Marian Balakowicz1372cce2008-03-12 10:33:01 +01002298 8 common/cmd_bootm.c No uncompress/copy overwrite error
wdenkc6097192002-11-03 00:24:07 +00002299 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
Marian Balakowicz1372cce2008-03-12 10:33:01 +01002300
2301 9 common/image.c Start initial ramdisk verification
2302 -10 common/image.c Ramdisk header has bad magic number
2303 -11 common/image.c Ramdisk header has bad checksum
2304 10 common/image.c Ramdisk header is OK
2305 -12 common/image.c Ramdisk data has bad checksum
2306 11 common/image.c Ramdisk data has correct checksum
2307 12 common/image.c Ramdisk verification complete, start loading
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002308 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk)
Marian Balakowicz1372cce2008-03-12 10:33:01 +01002309 13 common/image.c Start multifile image verification
2310 14 common/image.c No initial ramdisk, no multifile, continue.
2311
Wolfgang Denkc0f40852011-10-26 10:21:21 +00002312 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS
wdenkc6097192002-11-03 00:24:07 +00002313
Stefan Roesea47a12b2010-04-15 16:07:28 +02002314 -30 arch/powerpc/lib/board.c Fatal error, hang the system
wdenk11dadd52004-02-27 00:07:27 +00002315 -31 post/post.c POST test failed, detected by post_output_backlog()
2316 -32 post/post.c POST test failed, detected by post_run_single()
wdenk63e73c92004-02-23 22:22:28 +00002317
Heiko Schocher566a4942007-06-22 19:11:54 +02002318 34 common/cmd_doc.c before loading a Image from a DOC device
2319 -35 common/cmd_doc.c Bad usage of "doc" command
2320 35 common/cmd_doc.c correct usage of "doc" command
2321 -36 common/cmd_doc.c No boot device
2322 36 common/cmd_doc.c correct boot device
2323 -37 common/cmd_doc.c Unknown Chip ID on boot device
2324 37 common/cmd_doc.c correct chip ID found, device available
2325 -38 common/cmd_doc.c Read Error on boot device
2326 38 common/cmd_doc.c reading Image header from DOC device OK
2327 -39 common/cmd_doc.c Image header has bad magic number
2328 39 common/cmd_doc.c Image header has correct magic number
2329 -40 common/cmd_doc.c Error reading Image from DOC device
2330 40 common/cmd_doc.c Image header has correct magic number
2331 41 common/cmd_ide.c before loading a Image from a IDE device
2332 -42 common/cmd_ide.c Bad usage of "ide" command
2333 42 common/cmd_ide.c correct usage of "ide" command
2334 -43 common/cmd_ide.c No boot device
2335 43 common/cmd_ide.c boot device found
2336 -44 common/cmd_ide.c Device not available
2337 44 common/cmd_ide.c Device available
2338 -45 common/cmd_ide.c wrong partition selected
2339 45 common/cmd_ide.c partition selected
2340 -46 common/cmd_ide.c Unknown partition table
2341 46 common/cmd_ide.c valid partition table found
2342 -47 common/cmd_ide.c Invalid partition type
2343 47 common/cmd_ide.c correct partition type
2344 -48 common/cmd_ide.c Error reading Image Header on boot device
2345 48 common/cmd_ide.c reading Image Header from IDE device OK
2346 -49 common/cmd_ide.c Image header has bad magic number
2347 49 common/cmd_ide.c Image header has correct magic number
2348 -50 common/cmd_ide.c Image header has bad checksum
2349 50 common/cmd_ide.c Image header has correct checksum
2350 -51 common/cmd_ide.c Error reading Image from IDE device
2351 51 common/cmd_ide.c reading Image from IDE device OK
2352 52 common/cmd_nand.c before loading a Image from a NAND device
2353 -53 common/cmd_nand.c Bad usage of "nand" command
2354 53 common/cmd_nand.c correct usage of "nand" command
2355 -54 common/cmd_nand.c No boot device
2356 54 common/cmd_nand.c boot device found
2357 -55 common/cmd_nand.c Unknown Chip ID on boot device
2358 55 common/cmd_nand.c correct chip ID found, device available
2359 -56 common/cmd_nand.c Error reading Image Header on boot device
2360 56 common/cmd_nand.c reading Image Header from NAND device OK
2361 -57 common/cmd_nand.c Image header has bad magic number
2362 57 common/cmd_nand.c Image header has correct magic number
2363 -58 common/cmd_nand.c Error reading Image from NAND device
2364 58 common/cmd_nand.c reading Image from NAND device OK
wdenkc6097192002-11-03 00:24:07 +00002365
Heiko Schocher566a4942007-06-22 19:11:54 +02002366 -60 common/env_common.c Environment has a bad CRC, using default
wdenkc6097192002-11-03 00:24:07 +00002367
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002368 64 net/eth.c starting with Ethernet configuration.
Heiko Schocher566a4942007-06-22 19:11:54 +02002369 -64 net/eth.c no Ethernet found.
2370 65 net/eth.c Ethernet found.
wdenk206c60c2003-09-18 10:02:25 +00002371
Heiko Schocher566a4942007-06-22 19:11:54 +02002372 -80 common/cmd_net.c usage wrong
Joe Hershbergerbc0571f2015-04-08 01:41:21 -05002373 80 common/cmd_net.c before calling net_loop()
2374 -81 common/cmd_net.c some error in net_loop() occurred
2375 81 common/cmd_net.c net_loop() back without error
Heiko Schocher566a4942007-06-22 19:11:54 +02002376 -82 common/cmd_net.c size == 0 (File with size 0 loaded)
2377 82 common/cmd_net.c trying automatic boot
Wolfgang Denk74de7ae2009-04-01 23:34:12 +02002378 83 common/cmd_net.c running "source" command
2379 -83 common/cmd_net.c some error in automatic boot or "source" command
Heiko Schocher566a4942007-06-22 19:11:54 +02002380 84 common/cmd_net.c end without errors
wdenkc6097192002-11-03 00:24:07 +00002381
Marian Balakowicz1372cce2008-03-12 10:33:01 +01002382FIT uImage format:
2383
2384 Arg Where When
2385 100 common/cmd_bootm.c Kernel FIT Image has correct format
2386 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format
2387 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration
2388 -101 common/cmd_bootm.c Can't get configuration for kernel subimage
2389 102 common/cmd_bootm.c Kernel unit name specified
2390 -103 common/cmd_bootm.c Can't get kernel subimage node offset
Marian Balakowiczf773bea2008-03-12 10:35:46 +01002391 103 common/cmd_bootm.c Found configuration node
Marian Balakowicz1372cce2008-03-12 10:33:01 +01002392 104 common/cmd_bootm.c Got kernel subimage node offset
2393 -104 common/cmd_bootm.c Kernel subimage hash verification failed
2394 105 common/cmd_bootm.c Kernel subimage hash verification OK
2395 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture
2396 106 common/cmd_bootm.c Architecture check OK
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002397 -106 common/cmd_bootm.c Kernel subimage has wrong type
2398 107 common/cmd_bootm.c Kernel subimage type OK
Marian Balakowicz1372cce2008-03-12 10:33:01 +01002399 -107 common/cmd_bootm.c Can't get kernel subimage data/size
2400 108 common/cmd_bootm.c Got kernel subimage data/size
2401 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT)
2402 -109 common/cmd_bootm.c Can't get kernel subimage type
2403 -110 common/cmd_bootm.c Can't get kernel subimage comp
2404 -111 common/cmd_bootm.c Can't get kernel subimage os
2405 -112 common/cmd_bootm.c Can't get kernel subimage load address
2406 -113 common/cmd_bootm.c Image uncompress/copy overwrite error
2407
2408 120 common/image.c Start initial ramdisk verification
2409 -120 common/image.c Ramdisk FIT image has incorrect format
2410 121 common/image.c Ramdisk FIT image has correct format
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002411 122 common/image.c No ramdisk subimage unit name, using configuration
Marian Balakowicz1372cce2008-03-12 10:33:01 +01002412 -122 common/image.c Can't get configuration for ramdisk subimage
2413 123 common/image.c Ramdisk unit name specified
2414 -124 common/image.c Can't get ramdisk subimage node offset
2415 125 common/image.c Got ramdisk subimage node offset
2416 -125 common/image.c Ramdisk subimage hash verification failed
2417 126 common/image.c Ramdisk subimage hash verification OK
2418 -126 common/image.c Ramdisk subimage for unsupported architecture
2419 127 common/image.c Architecture check OK
2420 -127 common/image.c Can't get ramdisk subimage data/size
2421 128 common/image.c Got ramdisk subimage data/size
2422 129 common/image.c Can't get ramdisk load address
2423 -129 common/image.c Got ramdisk load address
2424
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002425 -130 common/cmd_doc.c Incorrect FIT image format
Marian Balakowicz1372cce2008-03-12 10:33:01 +01002426 131 common/cmd_doc.c FIT image format OK
2427
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002428 -140 common/cmd_ide.c Incorrect FIT image format
Marian Balakowicz1372cce2008-03-12 10:33:01 +01002429 141 common/cmd_ide.c FIT image format OK
2430
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002431 -150 common/cmd_nand.c Incorrect FIT image format
Marian Balakowicz1372cce2008-03-12 10:33:01 +01002432 151 common/cmd_nand.c FIT image format OK
2433
Heiko Schocher21d29f72014-05-28 11:33:33 +02002434- legacy image format:
2435 CONFIG_IMAGE_FORMAT_LEGACY
2436 enables the legacy image format support in U-Boot.
2437
2438 Default:
2439 enabled if CONFIG_FIT_SIGNATURE is not defined.
2440
2441 CONFIG_DISABLE_IMAGE_LEGACY
2442 disable the legacy image format
2443
2444 This define is introduced, as the legacy image format is
2445 enabled per default for backward compatibility.
2446
Wolfgang Denk4cf26092011-10-07 09:58:21 +02002447- Standalone program support:
2448 CONFIG_STANDALONE_LOAD_ADDR
2449
Wolfgang Denk6feff892011-10-09 21:06:34 +02002450 This option defines a board specific value for the
2451 address where standalone program gets loaded, thus
2452 overwriting the architecture dependent default
Wolfgang Denk4cf26092011-10-07 09:58:21 +02002453 settings.
2454
2455- Frame Buffer Address:
2456 CONFIG_FB_ADDR
2457
2458 Define CONFIG_FB_ADDR if you want to use specific
Wolfgang Denk44a53b52013-01-03 00:43:59 +00002459 address for frame buffer. This is typically the case
2460 when using a graphics controller has separate video
2461 memory. U-Boot will then place the frame buffer at
2462 the given address instead of dynamically reserving it
2463 in system RAM by calling lcd_setmem(), which grabs
2464 the memory for the frame buffer depending on the
2465 configured panel size.
Wolfgang Denk4cf26092011-10-07 09:58:21 +02002466
2467 Please see board_init_f function.
2468
Detlev Zundelcccfc2a2009-12-01 17:16:19 +01002469- Automatic software updates via TFTP server
2470 CONFIG_UPDATE_TFTP
2471 CONFIG_UPDATE_TFTP_CNT_MAX
2472 CONFIG_UPDATE_TFTP_MSEC_MAX
2473
2474 These options enable and control the auto-update feature;
2475 for a more detailed description refer to doc/README.update.
2476
2477- MTD Support (mtdparts command, UBI support)
2478 CONFIG_MTD_DEVICE
2479
2480 Adds the MTD device infrastructure from the Linux kernel.
2481 Needed for mtdparts command support.
2482
2483 CONFIG_MTD_PARTITIONS
2484
2485 Adds the MTD partitioning infrastructure from the Linux
2486 kernel. Needed for UBI support.
2487
Joe Hershberger70c219c2013-04-08 10:32:48 +00002488- UBI support
Joe Hershberger147162d2013-04-08 10:32:49 +00002489 CONFIG_UBI_SILENCE_MSG
2490
2491 Make the verbose messages from UBI stop printing. This leaves
2492 warnings and errors enabled.
2493
Heiko Schocherff94bc42014-06-24 10:10:04 +02002494
2495 CONFIG_MTD_UBI_WL_THRESHOLD
2496 This parameter defines the maximum difference between the highest
2497 erase counter value and the lowest erase counter value of eraseblocks
2498 of UBI devices. When this threshold is exceeded, UBI starts performing
2499 wear leveling by means of moving data from eraseblock with low erase
2500 counter to eraseblocks with high erase counter.
2501
2502 The default value should be OK for SLC NAND flashes, NOR flashes and
2503 other flashes which have eraseblock life-cycle 100000 or more.
2504 However, in case of MLC NAND flashes which typically have eraseblock
2505 life-cycle less than 10000, the threshold should be lessened (e.g.,
2506 to 128 or 256, although it does not have to be power of 2).
2507
2508 default: 4096
Simon Glassc654b512014-10-23 18:58:54 -06002509
Heiko Schocherff94bc42014-06-24 10:10:04 +02002510 CONFIG_MTD_UBI_BEB_LIMIT
2511 This option specifies the maximum bad physical eraseblocks UBI
2512 expects on the MTD device (per 1024 eraseblocks). If the
2513 underlying flash does not admit of bad eraseblocks (e.g. NOR
2514 flash), this value is ignored.
2515
2516 NAND datasheets often specify the minimum and maximum NVM
2517 (Number of Valid Blocks) for the flashes' endurance lifetime.
2518 The maximum expected bad eraseblocks per 1024 eraseblocks
2519 then can be calculated as "1024 * (1 - MinNVB / MaxNVB)",
2520 which gives 20 for most NANDs (MaxNVB is basically the total
2521 count of eraseblocks on the chip).
2522
2523 To put it differently, if this value is 20, UBI will try to
2524 reserve about 1.9% of physical eraseblocks for bad blocks
2525 handling. And that will be 1.9% of eraseblocks on the entire
2526 NAND chip, not just the MTD partition UBI attaches. This means
2527 that if you have, say, a NAND flash chip admits maximum 40 bad
2528 eraseblocks, and it is split on two MTD partitions of the same
2529 size, UBI will reserve 40 eraseblocks when attaching a
2530 partition.
2531
2532 default: 20
2533
2534 CONFIG_MTD_UBI_FASTMAP
2535 Fastmap is a mechanism which allows attaching an UBI device
2536 in nearly constant time. Instead of scanning the whole MTD device it
2537 only has to locate a checkpoint (called fastmap) on the device.
2538 The on-flash fastmap contains all information needed to attach
2539 the device. Using fastmap makes only sense on large devices where
2540 attaching by scanning takes long. UBI will not automatically install
2541 a fastmap on old images, but you can set the UBI parameter
2542 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT to 1 if you want so. Please note
2543 that fastmap-enabled images are still usable with UBI implementations
2544 without fastmap support. On typical flash devices the whole fastmap
2545 fits into one PEB. UBI will reserve PEBs to hold two fastmaps.
2546
2547 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT
2548 Set this parameter to enable fastmap automatically on images
2549 without a fastmap.
2550 default: 0
2551
Heiko Schocher0195a7b2015-10-22 06:19:21 +02002552 CONFIG_MTD_UBI_FM_DEBUG
2553 Enable UBI fastmap debug
2554 default: 0
2555
Joe Hershberger70c219c2013-04-08 10:32:48 +00002556- UBIFS support
Joe Hershberger147162d2013-04-08 10:32:49 +00002557 CONFIG_UBIFS_SILENCE_MSG
2558
2559 Make the verbose messages from UBIFS stop printing. This leaves
2560 warnings and errors enabled.
2561
Daniel Schwierzeck6a11cf42011-07-18 07:48:07 +00002562- SPL framework
Wolfgang Denk04e5ae72011-09-11 21:24:09 +02002563 CONFIG_SPL
2564 Enable building of SPL globally.
Daniel Schwierzeck6a11cf42011-07-18 07:48:07 +00002565
Tom Rini95579792012-02-14 07:29:40 +00002566 CONFIG_SPL_LDSCRIPT
2567 LDSCRIPT for linking the SPL binary.
2568
Albert ARIBAUD6ebc3462013-04-12 05:14:30 +00002569 CONFIG_SPL_MAX_FOOTPRINT
2570 Maximum size in memory allocated to the SPL, BSS included.
2571 When defined, the linker checks that the actual memory
2572 used by SPL from _start to __bss_end does not exceed it.
Albert ARIBAUD8960af82013-04-14 04:48:38 +00002573 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
Albert ARIBAUD6ebc3462013-04-12 05:14:30 +00002574 must not be both defined at the same time.
2575
Tom Rini95579792012-02-14 07:29:40 +00002576 CONFIG_SPL_MAX_SIZE
Albert ARIBAUD6ebc3462013-04-12 05:14:30 +00002577 Maximum size of the SPL image (text, data, rodata, and
2578 linker lists sections), BSS excluded.
2579 When defined, the linker checks that the actual size does
2580 not exceed it.
Tom Rini95579792012-02-14 07:29:40 +00002581
Wolfgang Denk04e5ae72011-09-11 21:24:09 +02002582 CONFIG_SPL_TEXT_BASE
2583 TEXT_BASE for linking the SPL binary.
Daniel Schwierzeck6a11cf42011-07-18 07:48:07 +00002584
Scott Wood94a45bb2012-09-20 19:05:12 -05002585 CONFIG_SPL_RELOC_TEXT_BASE
2586 Address to relocate to. If unspecified, this is equal to
2587 CONFIG_SPL_TEXT_BASE (i.e. no relocation is done).
2588
Tom Rini95579792012-02-14 07:29:40 +00002589 CONFIG_SPL_BSS_START_ADDR
2590 Link address for the BSS within the SPL binary.
2591
2592 CONFIG_SPL_BSS_MAX_SIZE
Albert ARIBAUD6ebc3462013-04-12 05:14:30 +00002593 Maximum size in memory allocated to the SPL BSS.
2594 When defined, the linker checks that the actual memory used
2595 by SPL from __bss_start to __bss_end does not exceed it.
Albert ARIBAUD8960af82013-04-14 04:48:38 +00002596 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
Albert ARIBAUD6ebc3462013-04-12 05:14:30 +00002597 must not be both defined at the same time.
Tom Rini95579792012-02-14 07:29:40 +00002598
2599 CONFIG_SPL_STACK
2600 Adress of the start of the stack SPL will use
2601
Albert ARIBAUD \(3ADEV\)8c80eb32015-03-31 11:40:50 +02002602 CONFIG_SPL_PANIC_ON_RAW_IMAGE
2603 When defined, SPL will panic() if the image it has
2604 loaded does not have a signature.
2605 Defining this is useful when code which loads images
2606 in SPL cannot guarantee that absolutely all read errors
2607 will be caught.
2608 An example is the LPC32XX MLC NAND driver, which will
2609 consider that a completely unreadable NAND block is bad,
2610 and thus should be skipped silently.
2611
Scott Wood94a45bb2012-09-20 19:05:12 -05002612 CONFIG_SPL_RELOC_STACK
2613 Adress of the start of the stack SPL will use after
2614 relocation. If unspecified, this is equal to
2615 CONFIG_SPL_STACK.
2616
Tom Rini95579792012-02-14 07:29:40 +00002617 CONFIG_SYS_SPL_MALLOC_START
2618 Starting address of the malloc pool used in SPL.
Fabio Estevam9ac4fc82015-11-12 12:30:19 -02002619 When this option is set the full malloc is used in SPL and
2620 it is set up by spl_init() and before that, the simple malloc()
2621 can be used if CONFIG_SYS_MALLOC_F is defined.
Tom Rini95579792012-02-14 07:29:40 +00002622
2623 CONFIG_SYS_SPL_MALLOC_SIZE
2624 The size of the malloc pool used in SPL.
Daniel Schwierzeck6a11cf42011-07-18 07:48:07 +00002625
Tom Rini9607faf2014-03-28 12:03:39 -04002626 CONFIG_SPL_OS_BOOT
2627 Enable booting directly to an OS from SPL.
2628 See also: doc/README.falcon
2629
Tom Rini861a86f2012-08-13 11:37:56 -07002630 CONFIG_SPL_DISPLAY_PRINT
2631 For ARM, enable an optional function to print more information
2632 about the running system.
2633
Scott Wood4b919722012-09-20 16:35:21 -05002634 CONFIG_SPL_INIT_MINIMAL
2635 Arch init code should be built for a very small image
2636
Paul Kocialkowskib97300b2014-11-08 23:14:56 +01002637 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_PARTITION
2638 Partition on the MMC to load U-Boot from when the MMC is being
2639 used in raw mode
2640
Peter Korsgaard2b75b0a2013-05-13 08:36:29 +00002641 CONFIG_SYS_MMCSD_RAW_MODE_KERNEL_SECTOR
2642 Sector to load kernel uImage from when MMC is being
2643 used in raw mode (for Falcon mode)
2644
2645 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTOR,
2646 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTORS
2647 Sector and number of sectors to load kernel argument
2648 parameters from when MMC is being used in raw mode
2649 (for falcon mode)
2650
Paul Kocialkowskie2ccdf82014-11-08 23:14:55 +01002651 CONFIG_SYS_MMCSD_FS_BOOT_PARTITION
2652 Partition on the MMC to load U-Boot from when the MMC is being
2653 used in fs mode
2654
Guillaume GARDETfae81c72014-10-15 17:53:13 +02002655 CONFIG_SPL_FS_LOAD_PAYLOAD_NAME
2656 Filename to read to load U-Boot when reading from filesystem
2657
2658 CONFIG_SPL_FS_LOAD_KERNEL_NAME
Peter Korsgaard7ad2cc72013-05-13 08:36:27 +00002659 Filename to read to load kernel uImage when reading
Guillaume GARDETfae81c72014-10-15 17:53:13 +02002660 from filesystem (for Falcon mode)
Peter Korsgaard7ad2cc72013-05-13 08:36:27 +00002661
Guillaume GARDETfae81c72014-10-15 17:53:13 +02002662 CONFIG_SPL_FS_LOAD_ARGS_NAME
Peter Korsgaard7ad2cc72013-05-13 08:36:27 +00002663 Filename to read to load kernel argument parameters
Guillaume GARDETfae81c72014-10-15 17:53:13 +02002664 when reading from filesystem (for Falcon mode)
Peter Korsgaard7ad2cc72013-05-13 08:36:27 +00002665
Scott Wood06f60ae2012-12-06 13:33:17 +00002666 CONFIG_SPL_MPC83XX_WAIT_FOR_NAND
2667 Set this for NAND SPL on PPC mpc83xx targets, so that
2668 start.S waits for the rest of the SPL to load before
2669 continuing (the hardware starts execution after just
2670 loading the first page rather than the full 4K).
2671
Prabhakar Kushwaha651fcf62014-04-08 19:12:31 +05302672 CONFIG_SPL_SKIP_RELOCATE
2673 Avoid SPL relocation
2674
Scott Wood6f2f01b2012-09-20 19:09:07 -05002675 CONFIG_SPL_NAND_BASE
2676 Include nand_base.c in the SPL. Requires
2677 CONFIG_SPL_NAND_DRIVERS.
2678
2679 CONFIG_SPL_NAND_DRIVERS
2680 SPL uses normal NAND drivers, not minimal drivers.
2681
2682 CONFIG_SPL_NAND_ECC
2683 Include standard software ECC in the SPL
2684
Tom Rini95579792012-02-14 07:29:40 +00002685 CONFIG_SPL_NAND_SIMPLE
Scott Wood7d4b7952012-09-21 18:35:27 -05002686 Support for NAND boot using simple NAND drivers that
2687 expose the cmd_ctrl() interface.
Tom Rini95579792012-02-14 07:29:40 +00002688
Thomas Gleixner6f4e7d32016-07-12 20:28:12 +02002689 CONFIG_SPL_UBI
2690 Support for a lightweight UBI (fastmap) scanner and
2691 loader
2692
Heiko Schocher0c3117b2014-10-31 08:31:00 +01002693 CONFIG_SPL_NAND_RAW_ONLY
2694 Support to boot only raw u-boot.bin images. Use this only
2695 if you need to save space.
2696
Ying Zhang7c8eea52013-08-16 15:16:12 +08002697 CONFIG_SPL_COMMON_INIT_DDR
2698 Set for common ddr init with serial presence detect in
2699 SPL binary.
2700
Tom Rini95579792012-02-14 07:29:40 +00002701 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT,
2702 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE,
2703 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS,
2704 CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE,
2705 CONFIG_SYS_NAND_ECCBYTES
2706 Defines the size and behavior of the NAND that SPL uses
Scott Wood7d4b7952012-09-21 18:35:27 -05002707 to read U-Boot
Tom Rini95579792012-02-14 07:29:40 +00002708
Prabhakar Kushwahafbe76ae2013-12-11 12:42:11 +05302709 CONFIG_SPL_NAND_BOOT
2710 Add support NAND boot
2711
Tom Rini95579792012-02-14 07:29:40 +00002712 CONFIG_SYS_NAND_U_BOOT_OFFS
Scott Wood7d4b7952012-09-21 18:35:27 -05002713 Location in NAND to read U-Boot from
2714
2715 CONFIG_SYS_NAND_U_BOOT_DST
2716 Location in memory to load U-Boot to
2717
2718 CONFIG_SYS_NAND_U_BOOT_SIZE
2719 Size of image to load
Tom Rini95579792012-02-14 07:29:40 +00002720
2721 CONFIG_SYS_NAND_U_BOOT_START
Scott Wood7d4b7952012-09-21 18:35:27 -05002722 Entry point in loaded image to jump to
Tom Rini95579792012-02-14 07:29:40 +00002723
2724 CONFIG_SYS_NAND_HW_ECC_OOBFIRST
2725 Define this if you need to first read the OOB and then the
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08002726 data. This is used, for example, on davinci platforms.
Tom Rini95579792012-02-14 07:29:40 +00002727
Pavel Machekc57b9532012-08-30 22:42:11 +02002728 CONFIG_SPL_RAM_DEVICE
2729 Support for running image already present in ram, in SPL binary
2730
Scott Wood74752ba2012-12-06 13:33:16 +00002731 CONFIG_SPL_PAD_TO
Benoît Thébaudeau6113d3f2013-04-11 09:35:49 +00002732 Image offset to which the SPL should be padded before appending
2733 the SPL payload. By default, this is defined as
2734 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
2735 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
2736 payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
Scott Wood74752ba2012-12-06 13:33:16 +00002737
Scott Woodca2fca22012-09-21 16:27:32 -05002738 CONFIG_SPL_TARGET
2739 Final target image containing SPL and payload. Some SPLs
2740 use an arch-specific makefile fragment instead, for
2741 example if more than one image needs to be produced.
2742
Simon Glass87ebee32013-05-08 08:05:59 +00002743 CONFIG_FIT_SPL_PRINT
2744 Printing information about a FIT image adds quite a bit of
2745 code to SPL. So this is normally disabled in SPL. Use this
2746 option to re-enable it. This will affect the output of the
2747 bootm command when booting a FIT image.
2748
Ying Zhang3aa29de2013-08-16 15:16:15 +08002749- TPL framework
2750 CONFIG_TPL
2751 Enable building of TPL globally.
2752
2753 CONFIG_TPL_PAD_TO
2754 Image offset to which the TPL should be padded before appending
2755 the TPL payload. By default, this is defined as
Wolfgang Denk93e14592013-10-04 17:43:24 +02002756 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
2757 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
2758 payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
Ying Zhang3aa29de2013-08-16 15:16:15 +08002759
wdenka8c7c702003-12-06 19:49:23 +00002760- Interrupt support (PPC):
2761
wdenkd4ca31c2004-01-02 14:00:00 +00002762 There are common interrupt_init() and timer_interrupt()
2763 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002764 for CPU specific initialization. interrupt_init_cpu()
wdenkd4ca31c2004-01-02 14:00:00 +00002765 should set decrementer_count to appropriate value. If
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002766 CPU resets decrementer automatically after interrupt
wdenkd4ca31c2004-01-02 14:00:00 +00002767 (ppc4xx) it should set decrementer_count to zero.
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002768 timer_interrupt() calls timer_interrupt_cpu() for CPU
wdenkd4ca31c2004-01-02 14:00:00 +00002769 specific handling. If board has watchdog / status_led
2770 / other_activity_monitor it works automatically from
2771 general timer_interrupt().
wdenka8c7c702003-12-06 19:49:23 +00002772
wdenkc6097192002-11-03 00:24:07 +00002773
Helmut Raiger9660e442011-10-20 04:19:47 +00002774Board initialization settings:
2775------------------------------
2776
2777During Initialization u-boot calls a number of board specific functions
2778to allow the preparation of board specific prerequisites, e.g. pin setup
2779before drivers are initialized. To enable these callbacks the
2780following configuration macros have to be defined. Currently this is
2781architecture specific, so please check arch/your_architecture/lib/board.c
2782typically in board_init_f() and board_init_r().
2783
2784- CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f()
2785- CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r()
2786- CONFIG_BOARD_LATE_INIT: Call board_late_init()
2787- CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init()
wdenkc6097192002-11-03 00:24:07 +00002788
wdenkc6097192002-11-03 00:24:07 +00002789Configuration Settings:
2790-----------------------
2791
York Sun4d1fd7f2014-02-26 17:03:19 -08002792- CONFIG_SYS_SUPPORT_64BIT_DATA: Defined automatically if compiled as 64-bit.
2793 Optionally it can be defined to support 64-bit memory commands.
2794
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002795- CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
wdenkc6097192002-11-03 00:24:07 +00002796 undefine this when you're short of memory.
2797
Peter Tyser2fb26042009-01-27 18:03:12 -06002798- CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
2799 width of the commands listed in the 'help' command output.
2800
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002801- CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to
wdenkc6097192002-11-03 00:24:07 +00002802 prompt for user input.
2803
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002804- CONFIG_SYS_CBSIZE: Buffer size for input from the Console
wdenkc6097192002-11-03 00:24:07 +00002805
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002806- CONFIG_SYS_PBSIZE: Buffer size for Console output
wdenkc6097192002-11-03 00:24:07 +00002807
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002808- CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands
wdenkc6097192002-11-03 00:24:07 +00002809
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002810- CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to
wdenkc6097192002-11-03 00:24:07 +00002811 the application (usually a Linux kernel) when it is
2812 booted
2813
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002814- CONFIG_SYS_BAUDRATE_TABLE:
wdenkc6097192002-11-03 00:24:07 +00002815 List of legal baudrate settings for this board.
2816
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002817- CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END:
wdenkc6097192002-11-03 00:24:07 +00002818 Begin and End addresses of the area used by the
2819 simple memory test.
2820
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002821- CONFIG_SYS_ALT_MEMTEST:
wdenk8bde7f72003-06-27 21:31:46 +00002822 Enable an alternate, more extensive memory test.
wdenkc6097192002-11-03 00:24:07 +00002823
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002824- CONFIG_SYS_MEMTEST_SCRATCH:
wdenk5f535fe2003-09-18 09:21:33 +00002825 Scratch address used by the alternate memory test
2826 You only need to set this if address zero isn't writeable
2827
York Sune8149522015-12-04 11:57:07 -08002828- CONFIG_SYS_MEM_RESERVE_SECURE
York Sune61a7532016-06-24 16:46:18 -07002829 Only implemented for ARMv8 for now.
York Sune8149522015-12-04 11:57:07 -08002830 If defined, the size of CONFIG_SYS_MEM_RESERVE_SECURE memory
2831 is substracted from total RAM and won't be reported to OS.
2832 This memory can be used as secure memory. A variable
York Sune61a7532016-06-24 16:46:18 -07002833 gd->arch.secure_ram is used to track the location. In systems
York Sune8149522015-12-04 11:57:07 -08002834 the RAM base is not zero, or RAM is divided into banks,
2835 this variable needs to be recalcuated to get the address.
2836
York Sunaabd7dd2015-12-07 11:05:29 -08002837- CONFIG_SYS_MEM_TOP_HIDE:
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002838 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header,
Stefan Roese14f73ca2008-03-26 10:14:11 +01002839 this specified memory area will get subtracted from the top
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002840 (end) of RAM and won't get "touched" at all by U-Boot. By
Stefan Roese14f73ca2008-03-26 10:14:11 +01002841 fixing up gd->ram_size the Linux kernel should gets passed
2842 the now "corrected" memory size and won't touch it either.
2843 This should work for arch/ppc and arch/powerpc. Only Linux
Stefan Roese5e12e752008-03-28 11:02:53 +01002844 board ports in arch/powerpc with bootwrapper support that
Stefan Roese14f73ca2008-03-26 10:14:11 +01002845 recalculate the memory size from the SDRAM controller setup
Stefan Roese5e12e752008-03-28 11:02:53 +01002846 will have to get fixed in Linux additionally.
Stefan Roese14f73ca2008-03-26 10:14:11 +01002847
2848 This option can be used as a workaround for the 440EPx/GRx
2849 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't
2850 be touched.
2851
2852 WARNING: Please make sure that this value is a multiple of
2853 the Linux page size (normally 4k). If this is not the case,
2854 then the end address of the Linux memory will be located at a
2855 non page size aligned address and this could cause major
2856 problems.
2857
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002858- CONFIG_SYS_LOADS_BAUD_CHANGE:
wdenkc6097192002-11-03 00:24:07 +00002859 Enable temporary baudrate change while serial download
2860
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002861- CONFIG_SYS_SDRAM_BASE:
wdenkc6097192002-11-03 00:24:07 +00002862 Physical start address of SDRAM. _Must_ be 0 here.
2863
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002864- CONFIG_SYS_FLASH_BASE:
wdenkc6097192002-11-03 00:24:07 +00002865 Physical start address of Flash memory.
2866
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002867- CONFIG_SYS_MONITOR_BASE:
wdenkc6097192002-11-03 00:24:07 +00002868 Physical start address of boot monitor code (set by
2869 make config files to be same as the text base address
Wolfgang Denk14d0a022010-10-07 21:51:12 +02002870 (CONFIG_SYS_TEXT_BASE) used when linking) - same as
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002871 CONFIG_SYS_FLASH_BASE when booting from flash.
wdenkc6097192002-11-03 00:24:07 +00002872
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002873- CONFIG_SYS_MONITOR_LEN:
wdenk8bde7f72003-06-27 21:31:46 +00002874 Size of memory reserved for monitor code, used to
2875 determine _at_compile_time_ (!) if the environment is
2876 embedded within the U-Boot image, or in a separate
2877 flash sector.
wdenkc6097192002-11-03 00:24:07 +00002878
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002879- CONFIG_SYS_MALLOC_LEN:
wdenkc6097192002-11-03 00:24:07 +00002880 Size of DRAM reserved for malloc() use.
2881
Simon Glassd59476b2014-07-10 22:23:28 -06002882- CONFIG_SYS_MALLOC_F_LEN
2883 Size of the malloc() pool for use before relocation. If
2884 this is defined, then a very simple malloc() implementation
2885 will become available before relocation. The address is just
2886 below the global data, and the stack is moved down to make
2887 space.
2888
2889 This feature allocates regions with increasing addresses
2890 within the region. calloc() is supported, but realloc()
2891 is not available. free() is supported but does nothing.
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08002892 The memory will be freed (or in fact just forgotten) when
Simon Glassd59476b2014-07-10 22:23:28 -06002893 U-Boot relocates itself.
2894
Simon Glass38687ae2014-11-10 17:16:54 -07002895- CONFIG_SYS_MALLOC_SIMPLE
2896 Provides a simple and small malloc() and calloc() for those
2897 boards which do not use the full malloc in SPL (which is
2898 enabled with CONFIG_SYS_SPL_MALLOC_START).
2899
Thierry Reding1dfdd9b2014-12-09 22:25:22 -07002900- CONFIG_SYS_NONCACHED_MEMORY:
2901 Size of non-cached memory area. This area of memory will be
2902 typically located right below the malloc() area and mapped
2903 uncached in the MMU. This is useful for drivers that would
2904 otherwise require a lot of explicit cache maintenance. For
2905 some drivers it's also impossible to properly maintain the
2906 cache. For example if the regions that need to be flushed
2907 are not a multiple of the cache-line size, *and* padding
2908 cannot be allocated between the regions to align them (i.e.
2909 if the HW requires a contiguous array of regions, and the
2910 size of each region is not cache-aligned), then a flush of
2911 one region may result in overwriting data that hardware has
2912 written to another region in the same cache-line. This can
2913 happen for example in network drivers where descriptors for
2914 buffers are typically smaller than the CPU cache-line (e.g.
2915 16 bytes vs. 32 or 64 bytes).
2916
2917 Non-cached memory is only supported on 32-bit ARM at present.
2918
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002919- CONFIG_SYS_BOOTM_LEN:
Stefan Roese15940c92006-03-13 11:16:36 +01002920 Normally compressed uImages are limited to an
2921 uncompressed size of 8 MBytes. If this is not enough,
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002922 you can define CONFIG_SYS_BOOTM_LEN in your board config file
Stefan Roese15940c92006-03-13 11:16:36 +01002923 to adjust this setting to your needs.
2924
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002925- CONFIG_SYS_BOOTMAPSZ:
wdenkc6097192002-11-03 00:24:07 +00002926 Maximum size of memory mapped by the startup code of
2927 the Linux kernel; all data that must be processed by
Bartlomiej Sieka7d721e32008-04-14 15:44:16 +02002928 the Linux kernel (bd_info, boot arguments, FDT blob if
2929 used) must be put below this limit, unless "bootm_low"
Robert P. J. Day1bce2ae2013-09-16 07:15:45 -04002930 environment variable is defined and non-zero. In such case
Bartlomiej Sieka7d721e32008-04-14 15:44:16 +02002931 all data for the Linux kernel must be between "bootm_low"
Wolfgang Denkc0f40852011-10-26 10:21:21 +00002932 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment
Grant Likelyc3624e62011-03-28 09:58:43 +00002933 variable "bootm_mapsize" will override the value of
2934 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined,
2935 then the value in "bootm_size" will be used instead.
wdenkc6097192002-11-03 00:24:07 +00002936
John Rigbyfca43cc2010-10-13 13:57:35 -06002937- CONFIG_SYS_BOOT_RAMDISK_HIGH:
2938 Enable initrd_high functionality. If defined then the
2939 initrd_high feature is enabled and the bootm ramdisk subcommand
2940 is enabled.
2941
2942- CONFIG_SYS_BOOT_GET_CMDLINE:
2943 Enables allocating and saving kernel cmdline in space between
2944 "bootm_low" and "bootm_low" + BOOTMAPSZ.
2945
2946- CONFIG_SYS_BOOT_GET_KBD:
2947 Enables allocating and saving a kernel copy of the bd_info in
2948 space between "bootm_low" and "bootm_low" + BOOTMAPSZ.
2949
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002950- CONFIG_SYS_MAX_FLASH_BANKS:
wdenkc6097192002-11-03 00:24:07 +00002951 Max number of Flash memory banks
2952
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002953- CONFIG_SYS_MAX_FLASH_SECT:
wdenkc6097192002-11-03 00:24:07 +00002954 Max number of sectors on a Flash chip
2955
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002956- CONFIG_SYS_FLASH_ERASE_TOUT:
wdenkc6097192002-11-03 00:24:07 +00002957 Timeout for Flash erase operations (in ms)
2958
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002959- CONFIG_SYS_FLASH_WRITE_TOUT:
wdenkc6097192002-11-03 00:24:07 +00002960 Timeout for Flash write operations (in ms)
2961
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002962- CONFIG_SYS_FLASH_LOCK_TOUT
wdenk8564acf2003-07-14 22:13:32 +00002963 Timeout for Flash set sector lock bit operation (in ms)
2964
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002965- CONFIG_SYS_FLASH_UNLOCK_TOUT
wdenk8564acf2003-07-14 22:13:32 +00002966 Timeout for Flash clear lock bits operation (in ms)
2967
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002968- CONFIG_SYS_FLASH_PROTECTION
wdenk8564acf2003-07-14 22:13:32 +00002969 If defined, hardware flash sectors protection is used
2970 instead of U-Boot software protection.
2971
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002972- CONFIG_SYS_DIRECT_FLASH_TFTP:
wdenkc6097192002-11-03 00:24:07 +00002973
2974 Enable TFTP transfers directly to flash memory;
2975 without this option such a download has to be
2976 performed in two steps: (1) download to RAM, and (2)
2977 copy from RAM to flash.
2978
2979 The two-step approach is usually more reliable, since
2980 you can check if the download worked before you erase
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002981 the flash, but in some situations (when system RAM is
2982 too limited to allow for a temporary copy of the
wdenkc6097192002-11-03 00:24:07 +00002983 downloaded image) this option may be very useful.
2984
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002985- CONFIG_SYS_FLASH_CFI:
wdenk43d96162003-03-06 00:02:04 +00002986 Define if the flash driver uses extra elements in the
wdenk5653fc32004-02-08 22:55:38 +00002987 common flash structure for storing flash geometry.
2988
Jean-Christophe PLAGNIOL-VILLARD00b18832008-08-13 01:40:42 +02002989- CONFIG_FLASH_CFI_DRIVER
wdenk5653fc32004-02-08 22:55:38 +00002990 This option also enables the building of the cfi_flash driver
2991 in the drivers directory
wdenkc6097192002-11-03 00:24:07 +00002992
Piotr Ziecik91809ed2008-11-17 15:57:58 +01002993- CONFIG_FLASH_CFI_MTD
2994 This option enables the building of the cfi_mtd driver
2995 in the drivers directory. The driver exports CFI flash
2996 to the MTD layer.
2997
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002998- CONFIG_SYS_FLASH_USE_BUFFER_WRITE
Guennadi Liakhovetski96ef8312008-04-03 13:36:02 +02002999 Use buffered writes to flash.
3000
3001- CONFIG_FLASH_SPANSION_S29WS_N
3002 s29ws-n MirrorBit flash has non-standard addresses for buffered
3003 write commands.
3004
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003005- CONFIG_SYS_FLASH_QUIET_TEST
Stefan Roese5568e612005-11-22 13:20:42 +01003006 If this option is defined, the common CFI flash doesn't
3007 print it's warning upon not recognized FLASH banks. This
3008 is useful, if some of the configured banks are only
3009 optionally available.
3010
Jerry Van Baren9a042e92008-03-08 13:48:01 -05003011- CONFIG_FLASH_SHOW_PROGRESS
3012 If defined (must be an integer), print out countdown
3013 digits and dots. Recommended value: 45 (9..1) for 80
3014 column displays, 15 (3..1) for 40 column displays.
3015
Stefan Roese352ef3f2013-04-04 15:53:14 +02003016- CONFIG_FLASH_VERIFY
3017 If defined, the content of the flash (destination) is compared
3018 against the source after the write operation. An error message
3019 will be printed when the contents are not identical.
3020 Please note that this option is useless in nearly all cases,
3021 since such flash programming errors usually are detected earlier
3022 while unprotecting/erasing/programming. Please only enable
3023 this option if you really know what you are doing.
3024
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003025- CONFIG_SYS_RX_ETH_BUFFER:
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02003026 Defines the number of Ethernet receive buffers. On some
3027 Ethernet controllers it is recommended to set this value
stroese53cf9432003-06-05 15:39:44 +00003028 to 8 or even higher (EEPRO100 or 405 EMAC), since all
3029 buffers can be full shortly after enabling the interface
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02003030 on high Ethernet traffic.
stroese53cf9432003-06-05 15:39:44 +00003031 Defaults to 4 if not defined.
3032
Wolfgang Denkea882ba2010-06-20 23:33:59 +02003033- CONFIG_ENV_MAX_ENTRIES
3034
Wolfgang Denk071bc922010-10-27 22:48:30 +02003035 Maximum number of entries in the hash table that is used
3036 internally to store the environment settings. The default
3037 setting is supposed to be generous and should work in most
3038 cases. This setting can be used to tune behaviour; see
3039 lib/hashtable.c for details.
Wolfgang Denkea882ba2010-06-20 23:33:59 +02003040
Joe Hershberger25980902012-12-11 22:16:31 -06003041- CONFIG_ENV_FLAGS_LIST_DEFAULT
3042- CONFIG_ENV_FLAGS_LIST_STATIC
Robert P. J. Day1bce2ae2013-09-16 07:15:45 -04003043 Enable validation of the values given to environment variables when
Joe Hershberger25980902012-12-11 22:16:31 -06003044 calling env set. Variables can be restricted to only decimal,
3045 hexadecimal, or boolean. If CONFIG_CMD_NET is also defined,
3046 the variables can also be restricted to IP address or MAC address.
3047
3048 The format of the list is:
3049 type_attribute = [s|d|x|b|i|m]
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08003050 access_attribute = [a|r|o|c]
3051 attributes = type_attribute[access_attribute]
Joe Hershberger25980902012-12-11 22:16:31 -06003052 entry = variable_name[:attributes]
3053 list = entry[,list]
3054
3055 The type attributes are:
3056 s - String (default)
3057 d - Decimal
3058 x - Hexadecimal
3059 b - Boolean ([1yYtT|0nNfF])
3060 i - IP address
3061 m - MAC address
3062
Joe Hershberger267541f2012-12-11 22:16:34 -06003063 The access attributes are:
3064 a - Any (default)
3065 r - Read-only
3066 o - Write-once
3067 c - Change-default
3068
Joe Hershberger25980902012-12-11 22:16:31 -06003069 - CONFIG_ENV_FLAGS_LIST_DEFAULT
3070 Define this to a list (string) to define the ".flags"
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08003071 environment variable in the default or embedded environment.
Joe Hershberger25980902012-12-11 22:16:31 -06003072
3073 - CONFIG_ENV_FLAGS_LIST_STATIC
3074 Define this to a list (string) to define validation that
3075 should be done if an entry is not found in the ".flags"
3076 environment variable. To override a setting in the static
3077 list, simply add an entry for the same variable name to the
3078 ".flags" variable.
3079
Joe Hershbergerbdf1fe42015-05-20 14:27:20 -05003080 If CONFIG_REGEX is defined, the variable_name above is evaluated as a
3081 regular expression. This allows multiple variables to define the same
3082 flags without explicitly listing them for each variable.
3083
Joe Hershberger267541f2012-12-11 22:16:34 -06003084- CONFIG_ENV_ACCESS_IGNORE_FORCE
3085 If defined, don't allow the -f switch to env set override variable
3086 access flags.
3087
Gabe Black0d296cc2014-10-15 04:38:30 -06003088- CONFIG_USE_STDINT
3089 If stdint.h is available with your toolchain you can define this
3090 option to enable it. You can provide option 'USE_STDINT=1' when
3091 building U-Boot to enable this.
3092
wdenkc6097192002-11-03 00:24:07 +00003093The following definitions that deal with the placement and management
3094of environment data (variable area); in general, we support the
3095following configurations:
3096
Mike Frysingerc3eb3fe2011-07-08 10:44:25 +00003097- CONFIG_BUILD_ENVCRC:
3098
3099 Builds up envcrc with the target environment so that external utils
3100 may easily extract it and embed it in final U-Boot images.
3101
wdenkc6097192002-11-03 00:24:07 +00003102BE CAREFUL! The first access to the environment happens quite early
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08003103in U-Boot initialization (when we try to get the setting of for the
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02003104console baudrate). You *MUST* have mapped your NVRAM area then, or
wdenkc6097192002-11-03 00:24:07 +00003105U-Boot will hang.
3106
3107Please note that even with NVRAM we still use a copy of the
3108environment in RAM: we could work on NVRAM directly, but we want to
3109keep settings there always unmodified except somebody uses "saveenv"
3110to save the current settings.
3111
Liu Gang0a85a9e2012-03-08 00:33:20 +00003112BE CAREFUL! For some special cases, the local device can not use
3113"saveenv" command. For example, the local device will get the
Liu Gangfc54c7f2012-08-09 05:10:01 +00003114environment stored in a remote NOR flash by SRIO or PCIE link,
3115but it can not erase, write this NOR flash by SRIO or PCIE interface.
Liu Gang0a85a9e2012-03-08 00:33:20 +00003116
Guennadi Liakhovetskib74ab732009-05-18 16:07:22 +02003117- CONFIG_NAND_ENV_DST
3118
3119 Defines address in RAM to which the nand_spl code should copy the
3120 environment. If redundant environment is used, it will be copied to
3121 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE.
3122
Bruce Adlere881cb52007-11-02 13:15:42 -07003123Please note that the environment is read-only until the monitor
wdenkc6097192002-11-03 00:24:07 +00003124has been relocated to RAM and a RAM copy of the environment has been
Simon Glass00caae62017-08-03 12:22:12 -06003125created; also, when using EEPROM you will have to use env_get_f()
wdenkc6097192002-11-03 00:24:07 +00003126until then to read environment variables.
3127
wdenk85ec0bc2003-03-31 16:34:49 +00003128The environment is protected by a CRC32 checksum. Before the monitor
3129is relocated into RAM, as a result of a bad CRC you will be working
3130with the compiled-in default environment - *silently*!!! [This is
3131necessary, because the first environment variable we need is the
3132"baudrate" setting for the console - if we have a bad CRC, we don't
3133have any device yet where we could complain.]
wdenkc6097192002-11-03 00:24:07 +00003134
3135Note: once the monitor has been relocated, then it will complain if
3136the default environment is used; a new CRC is computed as soon as you
wdenk85ec0bc2003-03-31 16:34:49 +00003137use the "saveenv" command to store a valid environment.
wdenkc6097192002-11-03 00:24:07 +00003138
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003139- CONFIG_SYS_FAULT_ECHO_LINK_DOWN:
wdenk42d1f032003-10-15 23:53:47 +00003140 Echo the inverted Ethernet link state to the fault LED.
wdenkfc3e2162003-10-08 22:33:00 +00003141
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003142 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR
wdenkfc3e2162003-10-08 22:33:00 +00003143 also needs to be defined.
3144
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003145- CONFIG_SYS_FAULT_MII_ADDR:
wdenk42d1f032003-10-15 23:53:47 +00003146 MII address of the PHY to check for the Ethernet link state.
wdenkc6097192002-11-03 00:24:07 +00003147
Ron Madridf5675aa2009-02-18 14:30:44 -08003148- CONFIG_NS16550_MIN_FUNCTIONS:
3149 Define this if you desire to only have use of the NS16550_init
3150 and NS16550_putc functions for the serial driver located at
3151 drivers/serial/ns16550.c. This option is useful for saving
3152 space for already greatly restricted images, including but not
3153 limited to NAND_SPL configurations.
3154
Simon Glassb2b92f52012-11-30 13:01:18 +00003155- CONFIG_DISPLAY_BOARDINFO
3156 Display information about the board that U-Boot is running on
3157 when U-Boot starts up. The board function checkboard() is called
3158 to do this.
3159
Simon Glasse2e3e2b2012-11-30 13:01:19 +00003160- CONFIG_DISPLAY_BOARDINFO_LATE
3161 Similar to the previous option, but display this information
3162 later, once stdio is running and output goes to the LCD, if
3163 present.
3164
Sascha Silbefeb85802013-08-11 16:40:43 +02003165- CONFIG_BOARD_SIZE_LIMIT:
3166 Maximum size of the U-Boot image. When defined, the
3167 build system checks that the actual size does not
3168 exceed it.
3169
wdenkc6097192002-11-03 00:24:07 +00003170Low Level (hardware related) configuration options:
wdenkdc7c9a12003-03-26 06:55:25 +00003171---------------------------------------------------
wdenkc6097192002-11-03 00:24:07 +00003172
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003173- CONFIG_SYS_CACHELINE_SIZE:
wdenkc6097192002-11-03 00:24:07 +00003174 Cache Line Size of the CPU.
3175
Timur Tabie46fedf2011-08-04 18:03:41 -05003176- CONFIG_SYS_CCSRBAR_DEFAULT:
3177 Default (power-on reset) physical address of CCSR on Freescale
3178 PowerPC SOCs.
3179
3180- CONFIG_SYS_CCSRBAR:
3181 Virtual address of CCSR. On a 32-bit build, this is typically
3182 the same value as CONFIG_SYS_CCSRBAR_DEFAULT.
3183
Timur Tabie46fedf2011-08-04 18:03:41 -05003184- CONFIG_SYS_CCSRBAR_PHYS:
3185 Physical address of CCSR. CCSR can be relocated to a new
3186 physical address, if desired. In this case, this macro should
Wolfgang Denkc0f40852011-10-26 10:21:21 +00003187 be set to that address. Otherwise, it should be set to the
Timur Tabie46fedf2011-08-04 18:03:41 -05003188 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR
3189 is typically relocated on 36-bit builds. It is recommended
3190 that this macro be defined via the _HIGH and _LOW macros:
3191
3192 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH
3193 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW)
3194
3195- CONFIG_SYS_CCSRBAR_PHYS_HIGH:
Wolfgang Denk4cf26092011-10-07 09:58:21 +02003196 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically
3197 either 0 (32-bit build) or 0xF (36-bit build). This macro is
Timur Tabie46fedf2011-08-04 18:03:41 -05003198 used in assembly code, so it must not contain typecasts or
3199 integer size suffixes (e.g. "ULL").
3200
3201- CONFIG_SYS_CCSRBAR_PHYS_LOW:
3202 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is
3203 used in assembly code, so it must not contain typecasts or
3204 integer size suffixes (e.g. "ULL").
3205
3206- CONFIG_SYS_CCSR_DO_NOT_RELOCATE:
3207 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be
3208 forced to a value that ensures that CCSR is not relocated.
3209
wdenk7f6c2cb2002-11-10 22:06:23 +00003210- Floppy Disk Support:
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003211 CONFIG_SYS_FDC_DRIVE_NUMBER
wdenk7f6c2cb2002-11-10 22:06:23 +00003212
3213 the default drive number (default value 0)
3214
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003215 CONFIG_SYS_ISA_IO_STRIDE
wdenk7f6c2cb2002-11-10 22:06:23 +00003216
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02003217 defines the spacing between FDC chipset registers
wdenk7f6c2cb2002-11-10 22:06:23 +00003218 (default value 1)
3219
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003220 CONFIG_SYS_ISA_IO_OFFSET
wdenk7f6c2cb2002-11-10 22:06:23 +00003221
wdenk43d96162003-03-06 00:02:04 +00003222 defines the offset of register from address. It
3223 depends on which part of the data bus is connected to
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02003224 the FDC chipset. (default value 0)
wdenk7f6c2cb2002-11-10 22:06:23 +00003225
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003226 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and
3227 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their
wdenk43d96162003-03-06 00:02:04 +00003228 default value.
wdenk7f6c2cb2002-11-10 22:06:23 +00003229
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003230 if CONFIG_SYS_FDC_HW_INIT is defined, then the function
wdenk43d96162003-03-06 00:02:04 +00003231 fdc_hw_init() is called at the beginning of the FDC
3232 setup. fdc_hw_init() must be provided by the board
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08003233 source code. It is used to make hardware-dependent
wdenk43d96162003-03-06 00:02:04 +00003234 initializations.
wdenk7f6c2cb2002-11-10 22:06:23 +00003235
Macpaul Lin0abddf82011-04-11 20:45:32 +00003236- CONFIG_IDE_AHB:
3237 Most IDE controllers were designed to be connected with PCI
3238 interface. Only few of them were designed for AHB interface.
3239 When software is doing ATA command and data transfer to
3240 IDE devices through IDE-AHB controller, some additional
3241 registers accessing to these kind of IDE-AHB controller
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08003242 is required.
Macpaul Lin0abddf82011-04-11 20:45:32 +00003243
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003244- CONFIG_SYS_IMMR: Physical address of the Internal Memory.
wdenkefe2a4d2004-12-16 21:44:03 +00003245 DO NOT CHANGE unless you know exactly what you're
Christophe Leroy907208c2017-07-06 10:23:22 +02003246 doing! (11-4) [MPC8xx systems only]
wdenkc6097192002-11-03 00:24:07 +00003247
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003248- CONFIG_SYS_INIT_RAM_ADDR:
wdenkc6097192002-11-03 00:24:07 +00003249
wdenk7152b1d2003-09-05 23:19:14 +00003250 Start address of memory area that can be used for
wdenkc6097192002-11-03 00:24:07 +00003251 initial data and stack; please note that this must be
3252 writable memory that is working WITHOUT special
3253 initialization, i. e. you CANNOT use normal RAM which
3254 will become available only after programming the
3255 memory controller and running certain initialization
3256 sequences.
3257
3258 U-Boot uses the following memory types:
Christophe Leroy907208c2017-07-06 10:23:22 +02003259 - MPC8xx: IMMR (internal memory of the CPU)
wdenkc6097192002-11-03 00:24:07 +00003260
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003261- CONFIG_SYS_GBL_DATA_OFFSET:
wdenkc6097192002-11-03 00:24:07 +00003262
3263 Offset of the initial data structure in the memory
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003264 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually
3265 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial
wdenkc6097192002-11-03 00:24:07 +00003266 data is located at the end of the available space
Wolfgang Denk553f0982010-10-26 13:32:32 +02003267 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE -
Simon Glassacd51f92016-10-02 18:01:06 -06003268 GENERATED_GBL_DATA_SIZE), and the initial stack is just
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003269 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR +
3270 CONFIG_SYS_GBL_DATA_OFFSET) downward.
wdenkc6097192002-11-03 00:24:07 +00003271
3272 Note:
3273 On the MPC824X (or other systems that use the data
3274 cache for initial memory) the address chosen for
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003275 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must
wdenkc6097192002-11-03 00:24:07 +00003276 point to an otherwise UNUSED address space between
3277 the top of RAM and the start of the PCI space.
3278
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003279- CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27)
wdenkc6097192002-11-03 00:24:07 +00003280
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003281- CONFIG_SYS_OR_TIMING_SDRAM:
wdenkc6097192002-11-03 00:24:07 +00003282 SDRAM timing
3283
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003284- CONFIG_SYS_MAMR_PTA:
wdenkc6097192002-11-03 00:24:07 +00003285 periodic timer for refresh
3286
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003287- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM,
3288 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP,
3289 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM,
3290 CONFIG_SYS_BR1_PRELIM:
wdenkc6097192002-11-03 00:24:07 +00003291 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
3292
3293- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003294 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM,
3295 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM:
wdenkc6097192002-11-03 00:24:07 +00003296 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
3297
Andrew Sharp69fd2d32012-08-29 14:16:32 +00003298- CONFIG_PCI_ENUM_ONLY
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08003299 Only scan through and get the devices on the buses.
Andrew Sharp69fd2d32012-08-29 14:16:32 +00003300 Don't do any setup work, presumably because someone or
3301 something has already done it, and we don't need to do it
3302 a second time. Useful for platforms that are pre-booted
3303 by coreboot or similar.
3304
Gabor Juhos842033e2013-05-30 07:06:12 +00003305- CONFIG_PCI_INDIRECT_BRIDGE:
3306 Enable support for indirect PCI bridges.
3307
Kumar Galaa09b9b62010-12-30 12:09:53 -06003308- CONFIG_SYS_SRIO:
3309 Chip has SRIO or not
3310
3311- CONFIG_SRIO1:
3312 Board has SRIO 1 port available
3313
3314- CONFIG_SRIO2:
3315 Board has SRIO 2 port available
3316
Liu Gangc8b28152013-05-07 16:30:46 +08003317- CONFIG_SRIO_PCIE_BOOT_MASTER
3318 Board can support master function for Boot from SRIO and PCIE
3319
Kumar Galaa09b9b62010-12-30 12:09:53 -06003320- CONFIG_SYS_SRIOn_MEM_VIRT:
3321 Virtual Address of SRIO port 'n' memory region
3322
3323- CONFIG_SYS_SRIOn_MEM_PHYS:
3324 Physical Address of SRIO port 'n' memory region
3325
3326- CONFIG_SYS_SRIOn_MEM_SIZE:
3327 Size of SRIO port 'n' memory region
3328
Fabio Estevam66bd1842013-04-11 09:35:34 +00003329- CONFIG_SYS_NAND_BUSWIDTH_16BIT
3330 Defined to tell the NAND controller that the NAND chip is using
3331 a 16 bit bus.
3332 Not all NAND drivers use this symbol.
Fabio Estevama430e912013-04-11 09:35:35 +00003333 Example of drivers that use it:
Fabio Estevam66bd1842013-04-11 09:35:34 +00003334 - drivers/mtd/nand/ndfc.c
Fabio Estevama430e912013-04-11 09:35:35 +00003335 - drivers/mtd/nand/mxc_nand.c
Alex Watermaneced4622011-05-19 15:08:36 -04003336
3337- CONFIG_SYS_NDFC_EBC0_CFG
3338 Sets the EBC0_CFG register for the NDFC. If not defined
3339 a default value will be used.
3340
Ben Warrenbb99ad62006-09-07 16:50:54 -04003341- CONFIG_SPD_EEPROM
Wolfgang Denk218ca722008-03-26 10:40:12 +01003342 Get DDR timing information from an I2C EEPROM. Common
3343 with pluggable memory modules such as SODIMMs
3344
Ben Warrenbb99ad62006-09-07 16:50:54 -04003345 SPD_EEPROM_ADDRESS
3346 I2C address of the SPD EEPROM
3347
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003348- CONFIG_SYS_SPD_BUS_NUM
Wolfgang Denk218ca722008-03-26 10:40:12 +01003349 If SPD EEPROM is on an I2C bus other than the first
3350 one, specify here. Note that the value must resolve
3351 to something your driver can deal with.
Ben Warrenbb99ad62006-09-07 16:50:54 -04003352
York Sun1b3e3c42011-06-07 09:42:16 +08003353- CONFIG_SYS_DDR_RAW_TIMING
3354 Get DDR timing information from other than SPD. Common with
3355 soldered DDR chips onboard without SPD. DDR raw timing
3356 parameters are extracted from datasheet and hard-coded into
3357 header files or board specific files.
3358
York Sun6f5e1dc2011-09-16 13:21:35 -07003359- CONFIG_FSL_DDR_INTERACTIVE
3360 Enable interactive DDR debugging. See doc/README.fsl-ddr.
3361
York Sune32d59a2015-01-06 13:18:55 -08003362- CONFIG_FSL_DDR_SYNC_REFRESH
3363 Enable sync of refresh for multiple controllers.
3364
York Sun4516ff82015-03-19 09:30:28 -07003365- CONFIG_FSL_DDR_BIST
3366 Enable built-in memory test for Freescale DDR controllers.
3367
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003368- CONFIG_SYS_83XX_DDR_USES_CS0
Wolfgang Denk218ca722008-03-26 10:40:12 +01003369 Only for 83xx systems. If specified, then DDR should
3370 be configured using CS0 and CS1 instead of CS2 and CS3.
Timur Tabi2ad6b512006-10-31 18:44:42 -06003371
wdenkc26e4542004-04-18 10:13:26 +00003372- CONFIG_RMII
3373 Enable RMII mode for all FECs.
3374 Note that this is a global option, we can't
3375 have one FEC in standard MII mode and another in RMII mode.
3376
wdenk5cf91d62004-04-23 20:32:05 +00003377- CONFIG_CRC32_VERIFY
3378 Add a verify option to the crc32 command.
3379 The syntax is:
3380
3381 => crc32 -v <address> <count> <crc32>
3382
3383 Where address/count indicate a memory area
3384 and crc32 is the correct crc32 which the
3385 area should have.
3386
wdenk56523f12004-07-11 17:40:54 +00003387- CONFIG_LOOPW
3388 Add the "loopw" memory command. This only takes effect if
Simon Glass493f4202017-08-04 16:34:27 -06003389 the memory commands are activated globally (CONFIG_CMD_MEMORY).
wdenk56523f12004-07-11 17:40:54 +00003390
stroese7b466642004-12-16 18:46:55 +00003391- CONFIG_MX_CYCLIC
3392 Add the "mdc" and "mwc" memory commands. These are cyclic
3393 "md/mw" commands.
3394 Examples:
3395
wdenkefe2a4d2004-12-16 21:44:03 +00003396 => mdc.b 10 4 500
stroese7b466642004-12-16 18:46:55 +00003397 This command will print 4 bytes (10,11,12,13) each 500 ms.
3398
wdenkefe2a4d2004-12-16 21:44:03 +00003399 => mwc.l 100 12345678 10
stroese7b466642004-12-16 18:46:55 +00003400 This command will write 12345678 to address 100 all 10 ms.
3401
wdenkefe2a4d2004-12-16 21:44:03 +00003402 This only takes effect if the memory commands are activated
Simon Glass493f4202017-08-04 16:34:27 -06003403 globally (CONFIG_CMD_MEMORY).
stroese7b466642004-12-16 18:46:55 +00003404
wdenk8aa1a2d2005-04-04 12:44:11 +00003405- CONFIG_SKIP_LOWLEVEL_INIT
Rick Chen3fafced2017-12-26 13:55:59 +08003406 [ARM, NDS32, MIPS, RISC-V only] If this variable is defined, then certain
Wolfgang Denk844f07d2010-11-27 23:30:56 +01003407 low level initializations (like setting up the memory
3408 controller) are omitted and/or U-Boot does not
3409 relocate itself into RAM.
wdenk8aa1a2d2005-04-04 12:44:11 +00003410
Wolfgang Denk844f07d2010-11-27 23:30:56 +01003411 Normally this variable MUST NOT be defined. The only
3412 exception is when U-Boot is loaded (to RAM) by some
3413 other boot loader or by a debugger which performs
3414 these initializations itself.
wdenk8aa1a2d2005-04-04 12:44:11 +00003415
Simon Glassb5bd0982016-05-05 07:28:06 -06003416- CONFIG_SKIP_LOWLEVEL_INIT_ONLY
3417 [ARM926EJ-S only] This allows just the call to lowlevel_init()
yeongjun Kim90211f72016-07-20 22:56:12 +09003418 to be skipped. The normal CP15 init (such as enabling the
Simon Glassb5bd0982016-05-05 07:28:06 -06003419 instruction cache) is still performed.
3420
Aneesh V401bb302011-07-13 05:11:07 +00003421- CONFIG_SPL_BUILD
Magnus Liljadf812382009-06-13 20:50:00 +02003422 Modifies the behaviour of start.S when compiling a loader
3423 that is executed before the actual U-Boot. E.g. when
3424 compiling a NAND SPL.
wdenk400558b2005-04-02 23:52:25 +00003425
Ying Zhang3aa29de2013-08-16 15:16:15 +08003426- CONFIG_TPL_BUILD
3427 Modifies the behaviour of start.S when compiling a loader
3428 that is executed after the SPL and before the actual U-Boot.
3429 It is loaded by the SPL.
3430
Ying Zhang5df572f2013-05-20 14:07:23 +08003431- CONFIG_SYS_MPC85XX_NO_RESETVEC
3432 Only for 85xx systems. If this variable is specified, the section
3433 .resetvec is not kept and the section .bootpg is placed in the
3434 previous 4k of the .text section.
3435
Simon Glass4213fc22013-02-24 17:33:14 +00003436- CONFIG_ARCH_MAP_SYSMEM
3437 Generally U-Boot (and in particular the md command) uses
3438 effective address. It is therefore not necessary to regard
3439 U-Boot address as virtual addresses that need to be translated
3440 to physical addresses. However, sandbox requires this, since
3441 it maintains its own little RAM buffer which contains all
3442 addressable memory. This option causes some memory accesses
3443 to be mapped through map_sysmem() / unmap_sysmem().
3444
Simon Glass588a13f2013-02-14 04:18:54 +00003445- CONFIG_X86_RESET_VECTOR
3446 If defined, the x86 reset vector code is included. This is not
3447 needed when U-Boot is running from Coreboot.
Gabe Blackb16f5212012-11-27 21:08:06 +00003448
Heiko Schocher16678eb2013-11-04 14:05:00 +01003449- CONFIG_SPL_AM33XX_ENABLE_RTC32K_OSC:
3450 Enables the RTC32K OSC on AM33xx based plattforms
3451
Karicheri, Muralidharan999d7d32014-04-04 13:16:50 -04003452- CONFIG_SYS_NAND_NO_SUBPAGE_WRITE
3453 Option to disable subpage write in NAND driver
3454 driver that uses this:
3455 drivers/mtd/nand/davinci_nand.c
3456
Timur Tabif2717b42011-11-22 09:21:25 -06003457Freescale QE/FMAN Firmware Support:
3458-----------------------------------
3459
3460The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the
3461loading of "firmware", which is encoded in the QE firmware binary format.
3462This firmware often needs to be loaded during U-Boot booting, so macros
3463are used to identify the storage device (NOR flash, SPI, etc) and the address
3464within that device.
3465
Zhao Qiangdcf1d772014-03-21 16:21:44 +08003466- CONFIG_SYS_FMAN_FW_ADDR
3467 The address in the storage device where the FMAN microcode is located. The
3468 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro
3469 is also specified.
3470
3471- CONFIG_SYS_QE_FW_ADDR
3472 The address in the storage device where the QE microcode is located. The
Timur Tabif2717b42011-11-22 09:21:25 -06003473 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro
3474 is also specified.
3475
3476- CONFIG_SYS_QE_FMAN_FW_LENGTH
3477 The maximum possible size of the firmware. The firmware binary format
3478 has a field that specifies the actual size of the firmware, but it
3479 might not be possible to read any part of the firmware unless some
3480 local storage is allocated to hold the entire firmware first.
3481
3482- CONFIG_SYS_QE_FMAN_FW_IN_NOR
3483 Specifies that QE/FMAN firmware is located in NOR flash, mapped as
3484 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the
3485 virtual address in NOR flash.
3486
3487- CONFIG_SYS_QE_FMAN_FW_IN_NAND
3488 Specifies that QE/FMAN firmware is located in NAND flash.
3489 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash.
3490
3491- CONFIG_SYS_QE_FMAN_FW_IN_MMC
3492 Specifies that QE/FMAN firmware is located on the primary SD/MMC
3493 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
3494
Liu Gang292dc6c2012-03-08 00:33:18 +00003495- CONFIG_SYS_QE_FMAN_FW_IN_REMOTE
3496 Specifies that QE/FMAN firmware is located in the remote (master)
3497 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which
Liu Gangfc54c7f2012-08-09 05:10:01 +00003498 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound
3499 window->master inbound window->master LAW->the ucode address in
3500 master's memory space.
Timur Tabif2717b42011-11-22 09:21:25 -06003501
J. German Riverab940ca62014-06-23 15:15:55 -07003502Freescale Layerscape Management Complex Firmware Support:
3503---------------------------------------------------------
3504The Freescale Layerscape Management Complex (MC) supports the loading of
3505"firmware".
3506This firmware often needs to be loaded during U-Boot booting, so macros
3507are used to identify the storage device (NOR flash, SPI, etc) and the address
3508within that device.
3509
3510- CONFIG_FSL_MC_ENET
3511 Enable the MC driver for Layerscape SoCs.
3512
Prabhakar Kushwaha5c055082015-06-02 10:55:52 +05303513Freescale Layerscape Debug Server Support:
3514-------------------------------------------
3515The Freescale Layerscape Debug Server Support supports the loading of
3516"Debug Server firmware" and triggering SP boot-rom.
3517This firmware often needs to be loaded during U-Boot booting.
3518
York Sunc0492142015-12-07 11:08:58 -08003519- CONFIG_SYS_MC_RSV_MEM_ALIGN
3520 Define alignment of reserved memory MC requires
Prabhakar Kushwaha5c055082015-06-02 10:55:52 +05303521
Paul Kocialkowskif3f431a2015-07-26 18:48:15 +02003522Reproducible builds
3523-------------------
3524
3525In order to achieve reproducible builds, timestamps used in the U-Boot build
3526process have to be set to a fixed value.
3527
3528This is done using the SOURCE_DATE_EPOCH environment variable.
3529SOURCE_DATE_EPOCH is to be set on the build host's shell, not as a configuration
3530option for U-Boot or an environment variable in U-Boot.
3531
3532SOURCE_DATE_EPOCH should be set to a number of seconds since the epoch, in UTC.
3533
wdenkc6097192002-11-03 00:24:07 +00003534Building the Software:
3535======================
3536
Wolfgang Denk218ca722008-03-26 10:40:12 +01003537Building U-Boot has been tested in several native build environments
3538and in many different cross environments. Of course we cannot support
3539all possibly existing versions of cross development tools in all
3540(potentially obsolete) versions. In case of tool chain problems we
3541recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK)
3542which is extensively used to build and test U-Boot.
wdenkc6097192002-11-03 00:24:07 +00003543
Wolfgang Denk218ca722008-03-26 10:40:12 +01003544If you are not using a native environment, it is assumed that you
3545have GNU cross compiling tools available in your path. In this case,
3546you must set the environment variable CROSS_COMPILE in your shell.
3547Note that no changes to the Makefile or any other source files are
3548necessary. For example using the ELDK on a 4xx CPU, please enter:
wdenkc6097192002-11-03 00:24:07 +00003549
Wolfgang Denk218ca722008-03-26 10:40:12 +01003550 $ CROSS_COMPILE=ppc_4xx-
3551 $ export CROSS_COMPILE
wdenkc6097192002-11-03 00:24:07 +00003552
Peter Tyser2f8d3962009-03-13 18:54:51 -05003553Note: If you wish to generate Windows versions of the utilities in
3554 the tools directory you can use the MinGW toolchain
3555 (http://www.mingw.org). Set your HOST tools to the MinGW
3556 toolchain and execute 'make tools'. For example:
3557
3558 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools
3559
3560 Binaries such as tools/mkimage.exe will be created which can
3561 be executed on computers running Windows.
3562
Wolfgang Denk218ca722008-03-26 10:40:12 +01003563U-Boot is intended to be simple to build. After installing the
3564sources you must configure U-Boot for one specific board type. This
wdenkc6097192002-11-03 00:24:07 +00003565is done by typing:
3566
Holger Freytherab584d62014-08-04 09:26:05 +02003567 make NAME_defconfig
wdenkc6097192002-11-03 00:24:07 +00003568
Holger Freytherab584d62014-08-04 09:26:05 +02003569where "NAME_defconfig" is the name of one of the existing configu-
Michael Jones4d675ae2012-03-15 22:48:10 +00003570rations; see boards.cfg for supported names.
wdenk54387ac2003-10-08 22:45:44 +00003571
wdenk2729af92004-05-03 20:45:30 +00003572Note: for some board special configuration names may exist; check if
3573 additional information is available from the board vendor; for
3574 instance, the TQM823L systems are available without (standard)
3575 or with LCD support. You can select such additional "features"
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02003576 when choosing the configuration, i. e.
wdenkc6097192002-11-03 00:24:07 +00003577
Holger Freytherab584d62014-08-04 09:26:05 +02003578 make TQM823L_defconfig
wdenk2729af92004-05-03 20:45:30 +00003579 - will configure for a plain TQM823L, i. e. no LCD support
wdenkc6097192002-11-03 00:24:07 +00003580
Holger Freytherab584d62014-08-04 09:26:05 +02003581 make TQM823L_LCD_defconfig
wdenk2729af92004-05-03 20:45:30 +00003582 - will configure for a TQM823L with U-Boot console on LCD
wdenkc6097192002-11-03 00:24:07 +00003583
wdenk2729af92004-05-03 20:45:30 +00003584 etc.
wdenkc6097192002-11-03 00:24:07 +00003585
wdenkc6097192002-11-03 00:24:07 +00003586
wdenk2729af92004-05-03 20:45:30 +00003587Finally, type "make all", and you should get some working U-Boot
3588images ready for download to / installation on your system:
wdenkc6097192002-11-03 00:24:07 +00003589
wdenk2729af92004-05-03 20:45:30 +00003590- "u-boot.bin" is a raw binary image
3591- "u-boot" is an image in ELF binary format
3592- "u-boot.srec" is in Motorola S-Record format
wdenkc6097192002-11-03 00:24:07 +00003593
Marian Balakowiczbaf31242006-09-07 17:25:40 +02003594By default the build is performed locally and the objects are saved
3595in the source directory. One of the two methods can be used to change
3596this behavior and build U-Boot to some external directory:
3597
35981. Add O= to the make command line invocations:
3599
3600 make O=/tmp/build distclean
Holger Freytherab584d62014-08-04 09:26:05 +02003601 make O=/tmp/build NAME_defconfig
Marian Balakowiczbaf31242006-09-07 17:25:40 +02003602 make O=/tmp/build all
3603
Timo Ketolaadbba992014-11-06 14:39:05 +020036042. Set environment variable KBUILD_OUTPUT to point to the desired location:
Marian Balakowiczbaf31242006-09-07 17:25:40 +02003605
Timo Ketolaadbba992014-11-06 14:39:05 +02003606 export KBUILD_OUTPUT=/tmp/build
Marian Balakowiczbaf31242006-09-07 17:25:40 +02003607 make distclean
Holger Freytherab584d62014-08-04 09:26:05 +02003608 make NAME_defconfig
Marian Balakowiczbaf31242006-09-07 17:25:40 +02003609 make all
3610
Timo Ketolaadbba992014-11-06 14:39:05 +02003611Note that the command line "O=" setting overrides the KBUILD_OUTPUT environment
Marian Balakowiczbaf31242006-09-07 17:25:40 +02003612variable.
3613
Daniel Schwierzeck215bb1c2018-01-26 16:31:04 +01003614User specific CPPFLAGS, AFLAGS and CFLAGS can be passed to the compiler by
3615setting the according environment variables KCPPFLAGS, KAFLAGS and KCFLAGS.
3616For example to treat all compiler warnings as errors:
3617
3618 make KCFLAGS=-Werror
wdenkc6097192002-11-03 00:24:07 +00003619
wdenk2729af92004-05-03 20:45:30 +00003620Please be aware that the Makefiles assume you are using GNU make, so
3621for instance on NetBSD you might need to use "gmake" instead of
3622native "make".
wdenkc6097192002-11-03 00:24:07 +00003623
wdenkc6097192002-11-03 00:24:07 +00003624
wdenk2729af92004-05-03 20:45:30 +00003625If the system board that you have is not listed, then you will need
3626to port U-Boot to your hardware platform. To do this, follow these
3627steps:
wdenkc6097192002-11-03 00:24:07 +00003628
Phil Sutter3c1496c2015-12-25 14:41:18 +010036291. Create a new directory to hold your board specific code. Add any
wdenk2729af92004-05-03 20:45:30 +00003630 files you need. In your board directory, you will need at least
Phil Sutter3c1496c2015-12-25 14:41:18 +01003631 the "Makefile" and a "<board>.c".
36322. Create a new configuration file "include/configs/<board>.h" for
3633 your board.
wdenk2729af92004-05-03 20:45:30 +000036343. If you're porting U-Boot to a new CPU, then also create a new
3635 directory to hold your CPU specific code. Add any files you need.
Holger Freytherab584d62014-08-04 09:26:05 +020036364. Run "make <board>_defconfig" with your new name.
wdenk2729af92004-05-03 20:45:30 +000036375. Type "make", and you should get a working "u-boot.srec" file
3638 to be installed on your target system.
36396. Debug and solve any problems that might arise.
3640 [Of course, this last step is much harder than it sounds.]
wdenkc6097192002-11-03 00:24:07 +00003641
wdenkc6097192002-11-03 00:24:07 +00003642
wdenk2729af92004-05-03 20:45:30 +00003643Testing of U-Boot Modifications, Ports to New Hardware, etc.:
3644==============================================================
wdenkc6097192002-11-03 00:24:07 +00003645
Wolfgang Denk218ca722008-03-26 10:40:12 +01003646If you have modified U-Boot sources (for instance added a new board
3647or support for new devices, a new CPU, etc.) you are expected to
wdenk2729af92004-05-03 20:45:30 +00003648provide feedback to the other developers. The feedback normally takes
3649the form of a "patch", i. e. a context diff against a certain (latest
Wolfgang Denk218ca722008-03-26 10:40:12 +01003650official or latest in the git repository) version of U-Boot sources.
wdenkc6097192002-11-03 00:24:07 +00003651
Wolfgang Denk218ca722008-03-26 10:40:12 +01003652But before you submit such a patch, please verify that your modifi-
3653cation did not break existing code. At least make sure that *ALL* of
wdenk2729af92004-05-03 20:45:30 +00003654the supported boards compile WITHOUT ANY compiler warnings. To do so,
Simon Glass6de80f22016-07-27 20:33:08 -06003655just run the buildman script (tools/buildman/buildman), which will
3656configure and build U-Boot for ALL supported system. Be warned, this
3657will take a while. Please see the buildman README, or run 'buildman -H'
3658for documentation.
Marian Balakowiczbaf31242006-09-07 17:25:40 +02003659
3660
wdenk2729af92004-05-03 20:45:30 +00003661See also "U-Boot Porting Guide" below.
wdenkc6097192002-11-03 00:24:07 +00003662
wdenkc6097192002-11-03 00:24:07 +00003663
wdenk2729af92004-05-03 20:45:30 +00003664Monitor Commands - Overview:
3665============================
wdenkc6097192002-11-03 00:24:07 +00003666
wdenk2729af92004-05-03 20:45:30 +00003667go - start application at address 'addr'
3668run - run commands in an environment variable
3669bootm - boot application image from memory
3670bootp - boot image via network using BootP/TFTP protocol
Marek Vasut44f074c2012-03-14 21:52:45 +00003671bootz - boot zImage from memory
wdenk2729af92004-05-03 20:45:30 +00003672tftpboot- boot image via network using TFTP protocol
3673 and env variables "ipaddr" and "serverip"
3674 (and eventually "gatewayip")
Simon Glass1fb7cd42011-10-24 18:00:07 +00003675tftpput - upload a file via network using TFTP protocol
wdenk2729af92004-05-03 20:45:30 +00003676rarpboot- boot image via network using RARP/TFTP protocol
3677diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
3678loads - load S-Record file over serial line
3679loadb - load binary file over serial line (kermit mode)
3680md - memory display
3681mm - memory modify (auto-incrementing)
3682nm - memory modify (constant address)
3683mw - memory write (fill)
3684cp - memory copy
3685cmp - memory compare
3686crc32 - checksum calculation
Peter Tyser0f89c542009-04-18 22:34:03 -05003687i2c - I2C sub-system
wdenk2729af92004-05-03 20:45:30 +00003688sspi - SPI utility commands
3689base - print or set address offset
3690printenv- print environment variables
3691setenv - set environment variables
3692saveenv - save environment variables to persistent storage
3693protect - enable or disable FLASH write protection
3694erase - erase FLASH memory
3695flinfo - print FLASH memory information
Karl O. Pinc10635af2012-08-03 05:57:21 +00003696nand - NAND memory operations (see doc/README.nand)
wdenk2729af92004-05-03 20:45:30 +00003697bdinfo - print Board Info structure
3698iminfo - print header information for application image
3699coninfo - print console devices and informations
3700ide - IDE sub-system
3701loop - infinite loop on address range
wdenk56523f12004-07-11 17:40:54 +00003702loopw - infinite write loop on address range
wdenk2729af92004-05-03 20:45:30 +00003703mtest - simple RAM test
3704icache - enable or disable instruction cache
3705dcache - enable or disable data cache
3706reset - Perform RESET of the CPU
3707echo - echo args to console
3708version - print monitor version
3709help - print online help
3710? - alias for 'help'
wdenkc6097192002-11-03 00:24:07 +00003711
wdenkc6097192002-11-03 00:24:07 +00003712
wdenk2729af92004-05-03 20:45:30 +00003713Monitor Commands - Detailed Description:
3714========================================
wdenkc6097192002-11-03 00:24:07 +00003715
wdenk2729af92004-05-03 20:45:30 +00003716TODO.
wdenkc6097192002-11-03 00:24:07 +00003717
wdenk2729af92004-05-03 20:45:30 +00003718For now: just type "help <command>".
wdenkc6097192002-11-03 00:24:07 +00003719
3720
wdenk2729af92004-05-03 20:45:30 +00003721Environment Variables:
3722======================
wdenkc6097192002-11-03 00:24:07 +00003723
wdenk2729af92004-05-03 20:45:30 +00003724U-Boot supports user configuration using Environment Variables which
3725can be made persistent by saving to Flash memory.
wdenkc6097192002-11-03 00:24:07 +00003726
wdenk2729af92004-05-03 20:45:30 +00003727Environment Variables are set using "setenv", printed using
3728"printenv", and saved to Flash using "saveenv". Using "setenv"
3729without a value can be used to delete a variable from the
3730environment. As long as you don't save the environment you are
3731working with an in-memory copy. In case the Flash area containing the
3732environment is erased by accident, a default environment is provided.
wdenkc6097192002-11-03 00:24:07 +00003733
Wolfgang Denkc96f86e2010-01-17 23:55:53 +01003734Some configuration options can be set using Environment Variables.
3735
3736List of environment variables (most likely not complete):
wdenkc6097192002-11-03 00:24:07 +00003737
wdenk2729af92004-05-03 20:45:30 +00003738 baudrate - see CONFIG_BAUDRATE
wdenkc6097192002-11-03 00:24:07 +00003739
wdenk2729af92004-05-03 20:45:30 +00003740 bootdelay - see CONFIG_BOOTDELAY
wdenkc6097192002-11-03 00:24:07 +00003741
wdenk2729af92004-05-03 20:45:30 +00003742 bootcmd - see CONFIG_BOOTCOMMAND
wdenkc6097192002-11-03 00:24:07 +00003743
wdenk2729af92004-05-03 20:45:30 +00003744 bootargs - Boot arguments when booting an RTOS image
wdenkc6097192002-11-03 00:24:07 +00003745
wdenk2729af92004-05-03 20:45:30 +00003746 bootfile - Name of the image to load with TFTP
wdenkc6097192002-11-03 00:24:07 +00003747
Bartlomiej Sieka7d721e32008-04-14 15:44:16 +02003748 bootm_low - Memory range available for image processing in the bootm
3749 command can be restricted. This variable is given as
3750 a hexadecimal number and defines lowest address allowed
3751 for use by the bootm command. See also "bootm_size"
3752 environment variable. Address defined by "bootm_low" is
3753 also the base of the initial memory mapping for the Linux
Grant Likelyc3624e62011-03-28 09:58:43 +00003754 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and
3755 bootm_mapsize.
3756
Wolfgang Denkc0f40852011-10-26 10:21:21 +00003757 bootm_mapsize - Size of the initial memory mapping for the Linux kernel.
Grant Likelyc3624e62011-03-28 09:58:43 +00003758 This variable is given as a hexadecimal number and it
3759 defines the size of the memory region starting at base
3760 address bootm_low that is accessible by the Linux kernel
3761 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used
3762 as the default value if it is defined, and bootm_size is
3763 used otherwise.
Bartlomiej Sieka7d721e32008-04-14 15:44:16 +02003764
3765 bootm_size - Memory range available for image processing in the bootm
3766 command can be restricted. This variable is given as
3767 a hexadecimal number and defines the size of the region
3768 allowed for use by the bootm command. See also "bootm_low"
3769 environment variable.
3770
Bartlomiej Sieka4bae9092008-10-01 15:26:31 +02003771 updatefile - Location of the software update file on a TFTP server, used
3772 by the automatic software update feature. Please refer to
3773 documentation in doc/README.update for more details.
3774
wdenk2729af92004-05-03 20:45:30 +00003775 autoload - if set to "no" (any string beginning with 'n'),
3776 "bootp" will just load perform a lookup of the
3777 configuration from the BOOTP server, but not try to
3778 load any image using TFTP
wdenkc6097192002-11-03 00:24:07 +00003779
wdenk2729af92004-05-03 20:45:30 +00003780 autostart - if set to "yes", an image loaded using the "bootp",
3781 "rarpboot", "tftpboot" or "diskboot" commands will
3782 be automatically started (by internally calling
3783 "bootm")
wdenkc6097192002-11-03 00:24:07 +00003784
wdenk2729af92004-05-03 20:45:30 +00003785 If set to "no", a standalone image passed to the
3786 "bootm" command will be copied to the load address
3787 (and eventually uncompressed), but NOT be started.
3788 This can be used to load and uncompress arbitrary
3789 data.
wdenkc6097192002-11-03 00:24:07 +00003790
David A. Longa28afca2011-07-09 16:40:19 -04003791 fdt_high - if set this restricts the maximum address that the
3792 flattened device tree will be copied into upon boot.
Shawn Guofa34f6b2012-01-09 21:54:08 +00003793 For example, if you have a system with 1 GB memory
3794 at physical address 0x10000000, while Linux kernel
3795 only recognizes the first 704 MB as low memory, you
3796 may need to set fdt_high as 0x3C000000 to have the
3797 device tree blob be copied to the maximum address
3798 of the 704 MB low memory, so that Linux kernel can
3799 access it during the boot procedure.
3800
David A. Longa28afca2011-07-09 16:40:19 -04003801 If this is set to the special value 0xFFFFFFFF then
3802 the fdt will not be copied at all on boot. For this
3803 to work it must reside in writable memory, have
3804 sufficient padding on the end of it for u-boot to
3805 add the information it needs into it, and the memory
3806 must be accessible by the kernel.
3807
Simon Glasseea63e02011-10-24 19:15:34 +00003808 fdtcontroladdr- if set this is the address of the control flattened
3809 device tree used by U-Boot when CONFIG_OF_CONTROL is
3810 defined.
3811
wdenk17ea1172004-06-06 21:51:03 +00003812 i2cfast - (PPC405GP|PPC405EP only)
3813 if set to 'y' configures Linux I2C driver for fast
3814 mode (400kHZ). This environment variable is used in
3815 initialization code. So, for changes to be effective
3816 it must be saved and board must be reset.
3817
wdenk2729af92004-05-03 20:45:30 +00003818 initrd_high - restrict positioning of initrd images:
3819 If this variable is not set, initrd images will be
3820 copied to the highest possible address in RAM; this
3821 is usually what you want since it allows for
3822 maximum initrd size. If for some reason you want to
3823 make sure that the initrd image is loaded below the
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003824 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment
wdenk2729af92004-05-03 20:45:30 +00003825 variable to a value of "no" or "off" or "0".
3826 Alternatively, you can set it to a maximum upper
3827 address to use (U-Boot will still check that it
3828 does not overwrite the U-Boot stack and data).
wdenkc6097192002-11-03 00:24:07 +00003829
wdenk2729af92004-05-03 20:45:30 +00003830 For instance, when you have a system with 16 MB
3831 RAM, and want to reserve 4 MB from use by Linux,
3832 you can do this by adding "mem=12M" to the value of
3833 the "bootargs" variable. However, now you must make
3834 sure that the initrd image is placed in the first
3835 12 MB as well - this can be done with
wdenkc6097192002-11-03 00:24:07 +00003836
wdenk2729af92004-05-03 20:45:30 +00003837 setenv initrd_high 00c00000
wdenkc6097192002-11-03 00:24:07 +00003838
wdenk2729af92004-05-03 20:45:30 +00003839 If you set initrd_high to 0xFFFFFFFF, this is an
3840 indication to U-Boot that all addresses are legal
3841 for the Linux kernel, including addresses in flash
3842 memory. In this case U-Boot will NOT COPY the
3843 ramdisk at all. This may be useful to reduce the
3844 boot time on your system, but requires that this
3845 feature is supported by your Linux kernel.
wdenk4a6fd342003-04-12 23:38:12 +00003846
wdenk2729af92004-05-03 20:45:30 +00003847 ipaddr - IP address; needed for tftpboot command
wdenkc6097192002-11-03 00:24:07 +00003848
wdenk2729af92004-05-03 20:45:30 +00003849 loadaddr - Default load address for commands like "bootp",
3850 "rarpboot", "tftpboot", "loadb" or "diskboot"
wdenkc6097192002-11-03 00:24:07 +00003851
wdenk2729af92004-05-03 20:45:30 +00003852 loads_echo - see CONFIG_LOADS_ECHO
wdenkc6097192002-11-03 00:24:07 +00003853
wdenk2729af92004-05-03 20:45:30 +00003854 serverip - TFTP server IP address; needed for tftpboot command
wdenk38b99262003-05-23 23:18:21 +00003855
wdenk2729af92004-05-03 20:45:30 +00003856 bootretry - see CONFIG_BOOT_RETRY_TIME
wdenkc6097192002-11-03 00:24:07 +00003857
wdenk2729af92004-05-03 20:45:30 +00003858 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
wdenkc6097192002-11-03 00:24:07 +00003859
wdenk2729af92004-05-03 20:45:30 +00003860 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
wdenkc6097192002-11-03 00:24:07 +00003861
Mike Frysingere2a53452011-10-02 10:01:27 +00003862 ethprime - controls which interface is used first.
wdenkc6097192002-11-03 00:24:07 +00003863
Mike Frysingere2a53452011-10-02 10:01:27 +00003864 ethact - controls which interface is currently active.
3865 For example you can do the following
wdenkc6097192002-11-03 00:24:07 +00003866
Heiko Schocher48690d82010-07-20 17:45:02 +02003867 => setenv ethact FEC
3868 => ping 192.168.0.1 # traffic sent on FEC
3869 => setenv ethact SCC
3870 => ping 10.0.0.1 # traffic sent on SCC
wdenkc6097192002-11-03 00:24:07 +00003871
Matthias Fuchse1692572008-01-17 07:45:05 +01003872 ethrotate - When set to "no" U-Boot does not go through all
3873 available network interfaces.
3874 It just stays at the currently selected interface.
3875
Wolfgang Denkc96f86e2010-01-17 23:55:53 +01003876 netretry - When set to "no" each network operation will
wdenk2729af92004-05-03 20:45:30 +00003877 either succeed or fail without retrying.
3878 When set to "once" the network operation will
3879 fail when all the available network interfaces
3880 are tried once without success.
3881 Useful on scripts which control the retry operation
3882 themselves.
wdenkc6097192002-11-03 00:24:07 +00003883
Jean-Christophe PLAGNIOL-VILLARDb4e2f892009-01-31 09:53:39 +01003884 npe_ucode - set load address for the NPE microcode
Jean-Christophe PLAGNIOL-VILLARDa1cf0272008-01-07 08:41:34 +01003885
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08003886 silent_linux - If set then Linux will be told to boot silently, by
Simon Glass8d51aac2013-07-16 20:10:00 -07003887 changing the console to be empty. If "yes" it will be
3888 made silent. If "no" it will not be made silent. If
3889 unset, then it will be made silent if the U-Boot console
3890 is silent.
3891
Albert ARIBAUD \(3ADEV\)f5fb7342015-10-12 00:02:57 +02003892 tftpsrcp - If this is set, the value is used for TFTP's
Wolfgang Denkecb0ccd2005-09-24 22:37:32 +02003893 UDP source port.
3894
Albert ARIBAUD \(3ADEV\)f5fb7342015-10-12 00:02:57 +02003895 tftpdstp - If this is set, the value is used for TFTP's UDP
Wolfgang Denk28cb9372005-09-24 23:25:46 +02003896 destination port instead of the Well Know Port 69.
3897
Wolfgang Denkc96f86e2010-01-17 23:55:53 +01003898 tftpblocksize - Block size to use for TFTP transfers; if not set,
3899 we use the TFTP server's default block size
3900
3901 tftptimeout - Retransmission timeout for TFTP packets (in milli-
3902 seconds, minimum value is 1000 = 1 second). Defines
3903 when a packet is considered to be lost so it has to
3904 be retransmitted. The default is 5000 = 5 seconds.
3905 Lowering this value may make downloads succeed
3906 faster in networks with high packet loss rates or
3907 with unreliable TFTP servers.
3908
Albert ARIBAUD \(3ADEV\)f5fb7342015-10-12 00:02:57 +02003909 tftptimeoutcountmax - maximum count of TFTP timeouts (no
3910 unit, minimum value = 0). Defines how many timeouts
3911 can happen during a single file transfer before that
3912 transfer is aborted. The default is 10, and 0 means
3913 'no timeouts allowed'. Increasing this value may help
3914 downloads succeed with high packet loss rates, or with
3915 unreliable TFTP servers or client hardware.
3916
Wolfgang Denkc96f86e2010-01-17 23:55:53 +01003917 vlan - When set to a value < 4095 the traffic over
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02003918 Ethernet is encapsulated/received over 802.1q
wdenk2729af92004-05-03 20:45:30 +00003919 VLAN tagged frames.
wdenka3d991b2004-04-15 21:48:45 +00003920
Alexandre Messier50768f52016-02-01 17:08:57 -05003921 bootpretryperiod - Period during which BOOTP/DHCP sends retries.
3922 Unsigned value, in milliseconds. If not set, the period will
3923 be either the default (28000), or a value based on
3924 CONFIG_NET_RETRY_COUNT, if defined. This value has
3925 precedence over the valu based on CONFIG_NET_RETRY_COUNT.
3926
Jason Hobbsdc0b7b02011-08-31 05:37:28 +00003927The following image location variables contain the location of images
3928used in booting. The "Image" column gives the role of the image and is
3929not an environment variable name. The other columns are environment
3930variable names. "File Name" gives the name of the file on a TFTP
3931server, "RAM Address" gives the location in RAM the image will be
3932loaded to, and "Flash Location" gives the image's address in NOR
3933flash or offset in NAND flash.
3934
3935*Note* - these variables don't have to be defined for all boards, some
Fabio Estevamaed9fed2015-04-25 18:53:10 -03003936boards currently use other variables for these purposes, and some
Jason Hobbsdc0b7b02011-08-31 05:37:28 +00003937boards use these variables for other purposes.
3938
Wolfgang Denkc0f40852011-10-26 10:21:21 +00003939Image File Name RAM Address Flash Location
3940----- --------- ----------- --------------
3941u-boot u-boot u-boot_addr_r u-boot_addr
3942Linux kernel bootfile kernel_addr_r kernel_addr
3943device tree blob fdtfile fdt_addr_r fdt_addr
3944ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr
Jason Hobbsdc0b7b02011-08-31 05:37:28 +00003945
wdenk2729af92004-05-03 20:45:30 +00003946The following environment variables may be used and automatically
3947updated by the network boot commands ("bootp" and "rarpboot"),
3948depending the information provided by your boot server:
wdenka3d991b2004-04-15 21:48:45 +00003949
wdenk2729af92004-05-03 20:45:30 +00003950 bootfile - see above
3951 dnsip - IP address of your Domain Name Server
3952 dnsip2 - IP address of your secondary Domain Name Server
3953 gatewayip - IP address of the Gateway (Router) to use
3954 hostname - Target hostname
3955 ipaddr - see above
3956 netmask - Subnet Mask
3957 rootpath - Pathname of the root filesystem on the NFS server
3958 serverip - see above
wdenka3d991b2004-04-15 21:48:45 +00003959
wdenka3d991b2004-04-15 21:48:45 +00003960
wdenk2729af92004-05-03 20:45:30 +00003961There are two special Environment Variables:
wdenkc6097192002-11-03 00:24:07 +00003962
wdenk2729af92004-05-03 20:45:30 +00003963 serial# - contains hardware identification information such
3964 as type string and/or serial number
3965 ethaddr - Ethernet address
wdenkc6097192002-11-03 00:24:07 +00003966
wdenk2729af92004-05-03 20:45:30 +00003967These variables can be set only once (usually during manufacturing of
3968the board). U-Boot refuses to delete or overwrite these variables
3969once they have been set once.
wdenkc6097192002-11-03 00:24:07 +00003970
3971
wdenk2729af92004-05-03 20:45:30 +00003972Further special Environment Variables:
wdenkc6097192002-11-03 00:24:07 +00003973
wdenk2729af92004-05-03 20:45:30 +00003974 ver - Contains the U-Boot version string as printed
3975 with the "version" command. This variable is
3976 readonly (see CONFIG_VERSION_VARIABLE).
wdenkc6097192002-11-03 00:24:07 +00003977
wdenkc6097192002-11-03 00:24:07 +00003978
wdenk2729af92004-05-03 20:45:30 +00003979Please note that changes to some configuration parameters may take
3980only effect after the next boot (yes, that's just like Windoze :-).
wdenkc6097192002-11-03 00:24:07 +00003981
stroesec1551ea2003-04-04 15:53:41 +00003982
Joe Hershberger170ab112012-12-11 22:16:24 -06003983Callback functions for environment variables:
3984---------------------------------------------
3985
3986For some environment variables, the behavior of u-boot needs to change
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08003987when their values are changed. This functionality allows functions to
Joe Hershberger170ab112012-12-11 22:16:24 -06003988be associated with arbitrary variables. On creation, overwrite, or
3989deletion, the callback will provide the opportunity for some side
3990effect to happen or for the change to be rejected.
3991
3992The callbacks are named and associated with a function using the
3993U_BOOT_ENV_CALLBACK macro in your board or driver code.
3994
3995These callbacks are associated with variables in one of two ways. The
3996static list can be added to by defining CONFIG_ENV_CALLBACK_LIST_STATIC
3997in the board configuration to a string that defines a list of
3998associations. The list must be in the following format:
3999
4000 entry = variable_name[:callback_name]
4001 list = entry[,list]
4002
4003If the callback name is not specified, then the callback is deleted.
4004Spaces are also allowed anywhere in the list.
4005
4006Callbacks can also be associated by defining the ".callbacks" variable
4007with the same list format above. Any association in ".callbacks" will
4008override any association in the static list. You can define
4009CONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08004010".callbacks" environment variable in the default or embedded environment.
Joe Hershberger170ab112012-12-11 22:16:24 -06004011
Joe Hershbergerbdf1fe42015-05-20 14:27:20 -05004012If CONFIG_REGEX is defined, the variable_name above is evaluated as a
4013regular expression. This allows multiple variables to be connected to
4014the same callback without explicitly listing them all out.
4015
Joe Hershberger170ab112012-12-11 22:16:24 -06004016
wdenk2729af92004-05-03 20:45:30 +00004017Command Line Parsing:
4018=====================
stroesec1551ea2003-04-04 15:53:41 +00004019
wdenk2729af92004-05-03 20:45:30 +00004020There are two different command line parsers available with U-Boot:
4021the old "simple" one, and the much more powerful "hush" shell:
stroesec1551ea2003-04-04 15:53:41 +00004022
wdenk2729af92004-05-03 20:45:30 +00004023Old, simple command line parser:
4024--------------------------------
wdenkc6097192002-11-03 00:24:07 +00004025
wdenk2729af92004-05-03 20:45:30 +00004026- supports environment variables (through setenv / saveenv commands)
4027- several commands on one line, separated by ';'
Wolfgang Denkfe126d82005-11-20 21:40:11 +01004028- variable substitution using "... ${name} ..." syntax
wdenk2729af92004-05-03 20:45:30 +00004029- special characters ('$', ';') can be escaped by prefixing with '\',
4030 for example:
Wolfgang Denkfe126d82005-11-20 21:40:11 +01004031 setenv bootcmd bootm \${address}
wdenk2729af92004-05-03 20:45:30 +00004032- You can also escape text by enclosing in single apostrophes, for example:
4033 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
wdenkc6097192002-11-03 00:24:07 +00004034
wdenk2729af92004-05-03 20:45:30 +00004035Hush shell:
4036-----------
wdenkf07771c2003-05-28 08:06:31 +00004037
wdenk2729af92004-05-03 20:45:30 +00004038- similar to Bourne shell, with control structures like
4039 if...then...else...fi, for...do...done; while...do...done,
4040 until...do...done, ...
4041- supports environment ("global") variables (through setenv / saveenv
4042 commands) and local shell variables (through standard shell syntax
4043 "name=value"); only environment variables can be used with "run"
4044 command
wdenkf07771c2003-05-28 08:06:31 +00004045
wdenk2729af92004-05-03 20:45:30 +00004046General rules:
4047--------------
wdenkf07771c2003-05-28 08:06:31 +00004048
wdenk2729af92004-05-03 20:45:30 +00004049(1) If a command line (or an environment variable executed by a "run"
4050 command) contains several commands separated by semicolon, and
4051 one of these commands fails, then the remaining commands will be
4052 executed anyway.
wdenkf07771c2003-05-28 08:06:31 +00004053
wdenk2729af92004-05-03 20:45:30 +00004054(2) If you execute several variables with one call to run (i. e.
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02004055 calling run with a list of variables as arguments), any failing
wdenk2729af92004-05-03 20:45:30 +00004056 command will cause "run" to terminate, i. e. the remaining
4057 variables are not executed.
wdenkf07771c2003-05-28 08:06:31 +00004058
wdenk2729af92004-05-03 20:45:30 +00004059Note for Redundant Ethernet Interfaces:
4060=======================================
wdenkf07771c2003-05-28 08:06:31 +00004061
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02004062Some boards come with redundant Ethernet interfaces; U-Boot supports
wdenk2729af92004-05-03 20:45:30 +00004063such configurations and is capable of automatic selection of a
4064"working" interface when needed. MAC assignment works as follows:
wdenkf07771c2003-05-28 08:06:31 +00004065
wdenk2729af92004-05-03 20:45:30 +00004066Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
4067MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
4068"eth1addr" (=>eth1), "eth2addr", ...
wdenkf07771c2003-05-28 08:06:31 +00004069
wdenk2729af92004-05-03 20:45:30 +00004070If the network interface stores some valid MAC address (for instance
4071in SROM), this is used as default address if there is NO correspon-
4072ding setting in the environment; if the corresponding environment
4073variable is set, this overrides the settings in the card; that means:
wdenkf07771c2003-05-28 08:06:31 +00004074
wdenk2729af92004-05-03 20:45:30 +00004075o If the SROM has a valid MAC address, and there is no address in the
4076 environment, the SROM's address is used.
wdenkc6097192002-11-03 00:24:07 +00004077
wdenk2729af92004-05-03 20:45:30 +00004078o If there is no valid address in the SROM, and a definition in the
4079 environment exists, then the value from the environment variable is
4080 used.
wdenkc6097192002-11-03 00:24:07 +00004081
wdenk2729af92004-05-03 20:45:30 +00004082o If both the SROM and the environment contain a MAC address, and
4083 both addresses are the same, this MAC address is used.
wdenkc6097192002-11-03 00:24:07 +00004084
wdenk2729af92004-05-03 20:45:30 +00004085o If both the SROM and the environment contain a MAC address, and the
4086 addresses differ, the value from the environment is used and a
4087 warning is printed.
wdenkc6097192002-11-03 00:24:07 +00004088
wdenk2729af92004-05-03 20:45:30 +00004089o If neither SROM nor the environment contain a MAC address, an error
Joe Hershbergerbef10142015-05-04 14:55:13 -05004090 is raised. If CONFIG_NET_RANDOM_ETHADDR is defined, then in this case
4091 a random, locally-assigned MAC is used.
wdenkc6097192002-11-03 00:24:07 +00004092
Ben Warrenecee9322010-04-26 11:11:46 -07004093If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses
Wolfgang Denkc0f40852011-10-26 10:21:21 +00004094will be programmed into hardware as part of the initialization process. This
Ben Warrenecee9322010-04-26 11:11:46 -07004095may be skipped by setting the appropriate 'ethmacskip' environment variable.
4096The naming convention is as follows:
4097"ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc.
wdenkc6097192002-11-03 00:24:07 +00004098
wdenk2729af92004-05-03 20:45:30 +00004099Image Formats:
4100==============
wdenkc6097192002-11-03 00:24:07 +00004101
Marian Balakowicz3310c542008-03-12 12:13:13 +01004102U-Boot is capable of booting (and performing other auxiliary operations on)
4103images in two formats:
4104
4105New uImage format (FIT)
4106-----------------------
4107
4108Flexible and powerful format based on Flattened Image Tree -- FIT (similar
4109to Flattened Device Tree). It allows the use of images with multiple
4110components (several kernels, ramdisks, etc.), with contents protected by
4111SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
4112
4113
4114Old uImage format
4115-----------------
4116
4117Old image format is based on binary files which can be basically anything,
4118preceded by a special header; see the definitions in include/image.h for
4119details; basically, the header defines the following image properties:
wdenkc6097192002-11-03 00:24:07 +00004120
wdenk2729af92004-05-03 20:45:30 +00004121* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
4122 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
Peter Tyserf5ed9e32008-09-08 14:56:49 -05004123 LynxOS, pSOS, QNX, RTEMS, INTEGRITY;
4124 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS,
4125 INTEGRITY).
Andy Shevchenkodaab59a2017-07-05 16:25:22 +03004126* Target CPU Architecture (Provisions for Alpha, ARM, Intel x86,
Macpaul Linafc1ce82011-10-19 20:41:11 +00004127 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
Andy Shevchenkodaab59a2017-07-05 16:25:22 +03004128 Currently supported: ARM, Intel x86, MIPS, NDS32, Nios II, PowerPC).
wdenk2729af92004-05-03 20:45:30 +00004129* Compression Type (uncompressed, gzip, bzip2)
4130* Load Address
4131* Entry Point
4132* Image Name
4133* Image Timestamp
wdenkc6097192002-11-03 00:24:07 +00004134
wdenk2729af92004-05-03 20:45:30 +00004135The header is marked by a special Magic Number, and both the header
4136and the data portions of the image are secured against corruption by
4137CRC32 checksums.
wdenkc6097192002-11-03 00:24:07 +00004138
wdenkc6097192002-11-03 00:24:07 +00004139
wdenk2729af92004-05-03 20:45:30 +00004140Linux Support:
4141==============
wdenkc6097192002-11-03 00:24:07 +00004142
wdenk2729af92004-05-03 20:45:30 +00004143Although U-Boot should support any OS or standalone application
4144easily, the main focus has always been on Linux during the design of
4145U-Boot.
wdenkc6097192002-11-03 00:24:07 +00004146
wdenk2729af92004-05-03 20:45:30 +00004147U-Boot includes many features that so far have been part of some
4148special "boot loader" code within the Linux kernel. Also, any
4149"initrd" images to be used are no longer part of one big Linux image;
4150instead, kernel and "initrd" are separate images. This implementation
4151serves several purposes:
wdenkc6097192002-11-03 00:24:07 +00004152
wdenk2729af92004-05-03 20:45:30 +00004153- the same features can be used for other OS or standalone
4154 applications (for instance: using compressed images to reduce the
4155 Flash memory footprint)
wdenkc6097192002-11-03 00:24:07 +00004156
wdenk2729af92004-05-03 20:45:30 +00004157- it becomes much easier to port new Linux kernel versions because
4158 lots of low-level, hardware dependent stuff are done by U-Boot
wdenkc6097192002-11-03 00:24:07 +00004159
wdenk2729af92004-05-03 20:45:30 +00004160- the same Linux kernel image can now be used with different "initrd"
4161 images; of course this also means that different kernel images can
4162 be run with the same "initrd". This makes testing easier (you don't
4163 have to build a new "zImage.initrd" Linux image when you just
4164 change a file in your "initrd"). Also, a field-upgrade of the
4165 software is easier now.
wdenkc6097192002-11-03 00:24:07 +00004166
wdenkc6097192002-11-03 00:24:07 +00004167
wdenk2729af92004-05-03 20:45:30 +00004168Linux HOWTO:
4169============
wdenkc6097192002-11-03 00:24:07 +00004170
wdenk2729af92004-05-03 20:45:30 +00004171Porting Linux to U-Boot based systems:
4172---------------------------------------
wdenkc6097192002-11-03 00:24:07 +00004173
wdenk2729af92004-05-03 20:45:30 +00004174U-Boot cannot save you from doing all the necessary modifications to
4175configure the Linux device drivers for use with your target hardware
4176(no, we don't intend to provide a full virtual machine interface to
4177Linux :-).
wdenkc6097192002-11-03 00:24:07 +00004178
Stefan Roesea47a12b2010-04-15 16:07:28 +02004179But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot).
wdenkc6097192002-11-03 00:24:07 +00004180
wdenk2729af92004-05-03 20:45:30 +00004181Just make sure your machine specific header file (for instance
4182include/asm-ppc/tqm8xx.h) includes the same definition of the Board
Markus Heidelberg1dc30692008-09-07 20:18:27 +02004183Information structure as we define in include/asm-<arch>/u-boot.h,
4184and make sure that your definition of IMAP_ADDR uses the same value
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02004185as your U-Boot configuration in CONFIG_SYS_IMMR.
wdenkc6097192002-11-03 00:24:07 +00004186
Simon Glass2eb31b12014-06-11 23:29:46 -06004187Note that U-Boot now has a driver model, a unified model for drivers.
4188If you are adding a new driver, plumb it into driver model. If there
4189is no uclass available, you are encouraged to create one. See
4190doc/driver-model.
4191
wdenkc6097192002-11-03 00:24:07 +00004192
wdenk2729af92004-05-03 20:45:30 +00004193Configuring the Linux kernel:
4194-----------------------------
wdenkc6097192002-11-03 00:24:07 +00004195
wdenk2729af92004-05-03 20:45:30 +00004196No specific requirements for U-Boot. Make sure you have some root
4197device (initial ramdisk, NFS) for your target system.
wdenkc6097192002-11-03 00:24:07 +00004198
wdenkc6097192002-11-03 00:24:07 +00004199
wdenk2729af92004-05-03 20:45:30 +00004200Building a Linux Image:
4201-----------------------
wdenkc6097192002-11-03 00:24:07 +00004202
wdenk2729af92004-05-03 20:45:30 +00004203With U-Boot, "normal" build targets like "zImage" or "bzImage" are
4204not used. If you use recent kernel source, a new build target
4205"uImage" will exist which automatically builds an image usable by
4206U-Boot. Most older kernels also have support for a "pImage" target,
4207which was introduced for our predecessor project PPCBoot and uses a
4208100% compatible format.
wdenkc6097192002-11-03 00:24:07 +00004209
wdenk2729af92004-05-03 20:45:30 +00004210Example:
wdenkc6097192002-11-03 00:24:07 +00004211
Holger Freytherab584d62014-08-04 09:26:05 +02004212 make TQM850L_defconfig
wdenk2729af92004-05-03 20:45:30 +00004213 make oldconfig
4214 make dep
4215 make uImage
wdenkc6097192002-11-03 00:24:07 +00004216
wdenk2729af92004-05-03 20:45:30 +00004217The "uImage" build target uses a special tool (in 'tools/mkimage') to
4218encapsulate a compressed Linux kernel image with header information,
4219CRC32 checksum etc. for use with U-Boot. This is what we are doing:
wdenkc6097192002-11-03 00:24:07 +00004220
wdenk2729af92004-05-03 20:45:30 +00004221* build a standard "vmlinux" kernel image (in ELF binary format):
wdenkc6097192002-11-03 00:24:07 +00004222
wdenk2729af92004-05-03 20:45:30 +00004223* convert the kernel into a raw binary image:
wdenkc6097192002-11-03 00:24:07 +00004224
wdenk2729af92004-05-03 20:45:30 +00004225 ${CROSS_COMPILE}-objcopy -O binary \
4226 -R .note -R .comment \
4227 -S vmlinux linux.bin
wdenkc6097192002-11-03 00:24:07 +00004228
wdenk2729af92004-05-03 20:45:30 +00004229* compress the binary image:
wdenkc6097192002-11-03 00:24:07 +00004230
wdenk2729af92004-05-03 20:45:30 +00004231 gzip -9 linux.bin
wdenkc6097192002-11-03 00:24:07 +00004232
wdenk2729af92004-05-03 20:45:30 +00004233* package compressed binary image for U-Boot:
wdenk24ee89b2002-11-03 17:56:27 +00004234
wdenk2729af92004-05-03 20:45:30 +00004235 mkimage -A ppc -O linux -T kernel -C gzip \
4236 -a 0 -e 0 -n "Linux Kernel Image" \
4237 -d linux.bin.gz uImage
wdenk24ee89b2002-11-03 17:56:27 +00004238
wdenk24ee89b2002-11-03 17:56:27 +00004239
wdenk2729af92004-05-03 20:45:30 +00004240The "mkimage" tool can also be used to create ramdisk images for use
4241with U-Boot, either separated from the Linux kernel image, or
4242combined into one file. "mkimage" encapsulates the images with a 64
4243byte header containing information about target architecture,
4244operating system, image type, compression method, entry points, time
4245stamp, CRC32 checksums, etc.
wdenk24ee89b2002-11-03 17:56:27 +00004246
wdenk2729af92004-05-03 20:45:30 +00004247"mkimage" can be called in two ways: to verify existing images and
4248print the header information, or to build new images.
wdenk24ee89b2002-11-03 17:56:27 +00004249
wdenk2729af92004-05-03 20:45:30 +00004250In the first form (with "-l" option) mkimage lists the information
4251contained in the header of an existing U-Boot image; this includes
4252checksum verification:
wdenk24ee89b2002-11-03 17:56:27 +00004253
wdenk2729af92004-05-03 20:45:30 +00004254 tools/mkimage -l image
4255 -l ==> list image header information
wdenk24ee89b2002-11-03 17:56:27 +00004256
wdenk2729af92004-05-03 20:45:30 +00004257The second form (with "-d" option) is used to build a U-Boot image
4258from a "data file" which is used as image payload:
wdenk24ee89b2002-11-03 17:56:27 +00004259
wdenk2729af92004-05-03 20:45:30 +00004260 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
4261 -n name -d data_file image
4262 -A ==> set architecture to 'arch'
4263 -O ==> set operating system to 'os'
4264 -T ==> set image type to 'type'
4265 -C ==> set compression type 'comp'
4266 -a ==> set load address to 'addr' (hex)
4267 -e ==> set entry point to 'ep' (hex)
4268 -n ==> set image name to 'name'
4269 -d ==> use image data from 'datafile'
wdenk24ee89b2002-11-03 17:56:27 +00004270
wdenk69459792004-05-29 16:53:29 +00004271Right now, all Linux kernels for PowerPC systems use the same load
4272address (0x00000000), but the entry point address depends on the
4273kernel version:
wdenkc6097192002-11-03 00:24:07 +00004274
wdenk2729af92004-05-03 20:45:30 +00004275- 2.2.x kernels have the entry point at 0x0000000C,
4276- 2.3.x and later kernels have the entry point at 0x00000000.
wdenkc6097192002-11-03 00:24:07 +00004277
wdenk2729af92004-05-03 20:45:30 +00004278So a typical call to build a U-Boot image would read:
wdenkc6097192002-11-03 00:24:07 +00004279
wdenk2729af92004-05-03 20:45:30 +00004280 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
4281 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
Stefan Roesea47a12b2010-04-15 16:07:28 +02004282 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \
wdenk2729af92004-05-03 20:45:30 +00004283 > examples/uImage.TQM850L
4284 Image Name: 2.4.4 kernel for TQM850L
4285 Created: Wed Jul 19 02:34:59 2000
4286 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4287 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
4288 Load Address: 0x00000000
4289 Entry Point: 0x00000000
wdenkc6097192002-11-03 00:24:07 +00004290
wdenk2729af92004-05-03 20:45:30 +00004291To verify the contents of the image (or check for corruption):
wdenkc6097192002-11-03 00:24:07 +00004292
wdenk2729af92004-05-03 20:45:30 +00004293 -> tools/mkimage -l examples/uImage.TQM850L
4294 Image Name: 2.4.4 kernel for TQM850L
4295 Created: Wed Jul 19 02:34:59 2000
4296 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4297 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
4298 Load Address: 0x00000000
4299 Entry Point: 0x00000000
wdenkc6097192002-11-03 00:24:07 +00004300
wdenk2729af92004-05-03 20:45:30 +00004301NOTE: for embedded systems where boot time is critical you can trade
4302speed for memory and install an UNCOMPRESSED image instead: this
4303needs more space in Flash, but boots much faster since it does not
4304need to be uncompressed:
wdenkc6097192002-11-03 00:24:07 +00004305
Stefan Roesea47a12b2010-04-15 16:07:28 +02004306 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz
wdenk2729af92004-05-03 20:45:30 +00004307 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
4308 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
Stefan Roesea47a12b2010-04-15 16:07:28 +02004309 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \
wdenk2729af92004-05-03 20:45:30 +00004310 > examples/uImage.TQM850L-uncompressed
4311 Image Name: 2.4.4 kernel for TQM850L
4312 Created: Wed Jul 19 02:34:59 2000
4313 Image Type: PowerPC Linux Kernel Image (uncompressed)
4314 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
4315 Load Address: 0x00000000
4316 Entry Point: 0x00000000
wdenkc6097192002-11-03 00:24:07 +00004317
wdenkc6097192002-11-03 00:24:07 +00004318
wdenk2729af92004-05-03 20:45:30 +00004319Similar you can build U-Boot images from a 'ramdisk.image.gz' file
4320when your kernel is intended to use an initial ramdisk:
wdenkdb01a2e2004-04-15 23:14:49 +00004321
wdenk2729af92004-05-03 20:45:30 +00004322 -> tools/mkimage -n 'Simple Ramdisk Image' \
4323 > -A ppc -O linux -T ramdisk -C gzip \
4324 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
4325 Image Name: Simple Ramdisk Image
4326 Created: Wed Jan 12 14:01:50 2000
4327 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
4328 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
4329 Load Address: 0x00000000
4330 Entry Point: 0x00000000
wdenkdb01a2e2004-04-15 23:14:49 +00004331
Guilherme Maciel Ferreiraa804b5c2013-12-01 12:43:11 -07004332The "dumpimage" is a tool to disassemble images built by mkimage. Its "-i"
4333option performs the converse operation of the mkimage's second form (the "-d"
4334option). Given an image built by mkimage, the dumpimage extracts a "data file"
4335from the image:
4336
Guilherme Maciel Ferreiraf41f5b72015-01-15 02:54:40 -02004337 tools/dumpimage -i image -T type -p position data_file
4338 -i ==> extract from the 'image' a specific 'data_file'
4339 -T ==> set image type to 'type'
4340 -p ==> 'position' (starting at 0) of the 'data_file' inside the 'image'
Guilherme Maciel Ferreiraa804b5c2013-12-01 12:43:11 -07004341
wdenkdb01a2e2004-04-15 23:14:49 +00004342
wdenk2729af92004-05-03 20:45:30 +00004343Installing a Linux Image:
4344-------------------------
wdenkdb01a2e2004-04-15 23:14:49 +00004345
wdenk2729af92004-05-03 20:45:30 +00004346To downloading a U-Boot image over the serial (console) interface,
4347you must convert the image to S-Record format:
wdenkdb01a2e2004-04-15 23:14:49 +00004348
wdenk2729af92004-05-03 20:45:30 +00004349 objcopy -I binary -O srec examples/image examples/image.srec
wdenkdb01a2e2004-04-15 23:14:49 +00004350
wdenk2729af92004-05-03 20:45:30 +00004351The 'objcopy' does not understand the information in the U-Boot
4352image header, so the resulting S-Record file will be relative to
4353address 0x00000000. To load it to a given address, you need to
4354specify the target address as 'offset' parameter with the 'loads'
4355command.
wdenkc6097192002-11-03 00:24:07 +00004356
wdenk2729af92004-05-03 20:45:30 +00004357Example: install the image to address 0x40100000 (which on the
4358TQM8xxL is in the first Flash bank):
wdenkc6097192002-11-03 00:24:07 +00004359
wdenk2729af92004-05-03 20:45:30 +00004360 => erase 40100000 401FFFFF
wdenkc6097192002-11-03 00:24:07 +00004361
wdenk2729af92004-05-03 20:45:30 +00004362 .......... done
4363 Erased 8 sectors
wdenkc6097192002-11-03 00:24:07 +00004364
wdenk2729af92004-05-03 20:45:30 +00004365 => loads 40100000
4366 ## Ready for S-Record download ...
4367 ~>examples/image.srec
4368 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
4369 ...
4370 15989 15990 15991 15992
4371 [file transfer complete]
4372 [connected]
4373 ## Start Addr = 0x00000000
wdenkc6097192002-11-03 00:24:07 +00004374
4375
wdenk2729af92004-05-03 20:45:30 +00004376You can check the success of the download using the 'iminfo' command;
Wolfgang Denk218ca722008-03-26 10:40:12 +01004377this includes a checksum verification so you can be sure no data
wdenk2729af92004-05-03 20:45:30 +00004378corruption happened:
wdenkc6097192002-11-03 00:24:07 +00004379
wdenk2729af92004-05-03 20:45:30 +00004380 => imi 40100000
wdenkc6097192002-11-03 00:24:07 +00004381
wdenk2729af92004-05-03 20:45:30 +00004382 ## Checking Image at 40100000 ...
4383 Image Name: 2.2.13 for initrd on TQM850L
4384 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4385 Data Size: 335725 Bytes = 327 kB = 0 MB
4386 Load Address: 00000000
4387 Entry Point: 0000000c
4388 Verifying Checksum ... OK
wdenkc6097192002-11-03 00:24:07 +00004389
4390
wdenk2729af92004-05-03 20:45:30 +00004391Boot Linux:
4392-----------
wdenkc6097192002-11-03 00:24:07 +00004393
wdenk2729af92004-05-03 20:45:30 +00004394The "bootm" command is used to boot an application that is stored in
4395memory (RAM or Flash). In case of a Linux kernel image, the contents
4396of the "bootargs" environment variable is passed to the kernel as
4397parameters. You can check and modify this variable using the
4398"printenv" and "setenv" commands:
wdenkc6097192002-11-03 00:24:07 +00004399
4400
wdenk2729af92004-05-03 20:45:30 +00004401 => printenv bootargs
4402 bootargs=root=/dev/ram
wdenkc6097192002-11-03 00:24:07 +00004403
wdenk2729af92004-05-03 20:45:30 +00004404 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
wdenkc6097192002-11-03 00:24:07 +00004405
wdenk2729af92004-05-03 20:45:30 +00004406 => printenv bootargs
4407 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
wdenkc6097192002-11-03 00:24:07 +00004408
wdenk2729af92004-05-03 20:45:30 +00004409 => bootm 40020000
4410 ## Booting Linux kernel at 40020000 ...
4411 Image Name: 2.2.13 for NFS on TQM850L
4412 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4413 Data Size: 381681 Bytes = 372 kB = 0 MB
4414 Load Address: 00000000
4415 Entry Point: 0000000c
4416 Verifying Checksum ... OK
4417 Uncompressing Kernel Image ... OK
4418 Linux version 2.2.13 (wd@denx.local.net) (gcc version 2.95.2 19991024 (release)) #1 Wed Jul 19 02:35:17 MEST 2000
4419 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
4420 time_init: decrementer frequency = 187500000/60
4421 Calibrating delay loop... 49.77 BogoMIPS
4422 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
4423 ...
wdenkc6097192002-11-03 00:24:07 +00004424
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02004425If you want to boot a Linux kernel with initial RAM disk, you pass
wdenk2729af92004-05-03 20:45:30 +00004426the memory addresses of both the kernel and the initrd image (PPBCOOT
4427format!) to the "bootm" command:
wdenkc6097192002-11-03 00:24:07 +00004428
wdenk2729af92004-05-03 20:45:30 +00004429 => imi 40100000 40200000
wdenkc6097192002-11-03 00:24:07 +00004430
wdenk2729af92004-05-03 20:45:30 +00004431 ## Checking Image at 40100000 ...
4432 Image Name: 2.2.13 for initrd on TQM850L
4433 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4434 Data Size: 335725 Bytes = 327 kB = 0 MB
4435 Load Address: 00000000
4436 Entry Point: 0000000c
4437 Verifying Checksum ... OK
wdenkc6097192002-11-03 00:24:07 +00004438
wdenk2729af92004-05-03 20:45:30 +00004439 ## Checking Image at 40200000 ...
4440 Image Name: Simple Ramdisk Image
4441 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
4442 Data Size: 566530 Bytes = 553 kB = 0 MB
4443 Load Address: 00000000
4444 Entry Point: 00000000
4445 Verifying Checksum ... OK
wdenkc6097192002-11-03 00:24:07 +00004446
wdenk2729af92004-05-03 20:45:30 +00004447 => bootm 40100000 40200000
4448 ## Booting Linux kernel at 40100000 ...
4449 Image Name: 2.2.13 for initrd on TQM850L
4450 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4451 Data Size: 335725 Bytes = 327 kB = 0 MB
4452 Load Address: 00000000
4453 Entry Point: 0000000c
4454 Verifying Checksum ... OK
4455 Uncompressing Kernel Image ... OK
4456 ## Loading RAMDisk Image at 40200000 ...
4457 Image Name: Simple Ramdisk Image
4458 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
4459 Data Size: 566530 Bytes = 553 kB = 0 MB
4460 Load Address: 00000000
4461 Entry Point: 00000000
4462 Verifying Checksum ... OK
4463 Loading Ramdisk ... OK
4464 Linux version 2.2.13 (wd@denx.local.net) (gcc version 2.95.2 19991024 (release)) #1 Wed Jul 19 02:32:08 MEST 2000
4465 Boot arguments: root=/dev/ram
4466 time_init: decrementer frequency = 187500000/60
4467 Calibrating delay loop... 49.77 BogoMIPS
4468 ...
4469 RAMDISK: Compressed image found at block 0
4470 VFS: Mounted root (ext2 filesystem).
wdenkc6097192002-11-03 00:24:07 +00004471
wdenk2729af92004-05-03 20:45:30 +00004472 bash#
wdenkc6097192002-11-03 00:24:07 +00004473
Matthew McClintock02677682006-06-28 10:41:37 -05004474Boot Linux and pass a flat device tree:
4475-----------
4476
4477First, U-Boot must be compiled with the appropriate defines. See the section
4478titled "Linux Kernel Interface" above for a more in depth explanation. The
4479following is an example of how to start a kernel and pass an updated
4480flat device tree:
4481
4482=> print oftaddr
4483oftaddr=0x300000
4484=> print oft
4485oft=oftrees/mpc8540ads.dtb
4486=> tftp $oftaddr $oft
4487Speed: 1000, full duplex
4488Using TSEC0 device
4489TFTP from server 192.168.1.1; our IP address is 192.168.1.101
4490Filename 'oftrees/mpc8540ads.dtb'.
4491Load address: 0x300000
4492Loading: #
4493done
4494Bytes transferred = 4106 (100a hex)
4495=> tftp $loadaddr $bootfile
4496Speed: 1000, full duplex
4497Using TSEC0 device
4498TFTP from server 192.168.1.1; our IP address is 192.168.1.2
4499Filename 'uImage'.
4500Load address: 0x200000
4501Loading:############
4502done
4503Bytes transferred = 1029407 (fb51f hex)
4504=> print loadaddr
4505loadaddr=200000
4506=> print oftaddr
4507oftaddr=0x300000
4508=> bootm $loadaddr - $oftaddr
4509## Booting image at 00200000 ...
Wolfgang Denka9398e02006-11-27 15:32:42 +01004510 Image Name: Linux-2.6.17-dirty
4511 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4512 Data Size: 1029343 Bytes = 1005.2 kB
Matthew McClintock02677682006-06-28 10:41:37 -05004513 Load Address: 00000000
Wolfgang Denka9398e02006-11-27 15:32:42 +01004514 Entry Point: 00000000
Matthew McClintock02677682006-06-28 10:41:37 -05004515 Verifying Checksum ... OK
4516 Uncompressing Kernel Image ... OK
4517Booting using flat device tree at 0x300000
4518Using MPC85xx ADS machine description
4519Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb
4520[snip]
4521
4522
wdenk2729af92004-05-03 20:45:30 +00004523More About U-Boot Image Types:
4524------------------------------
wdenk6069ff22003-02-28 00:49:47 +00004525
wdenk2729af92004-05-03 20:45:30 +00004526U-Boot supports the following image types:
wdenk6069ff22003-02-28 00:49:47 +00004527
wdenk2729af92004-05-03 20:45:30 +00004528 "Standalone Programs" are directly runnable in the environment
4529 provided by U-Boot; it is expected that (if they behave
4530 well) you can continue to work in U-Boot after return from
4531 the Standalone Program.
4532 "OS Kernel Images" are usually images of some Embedded OS which
4533 will take over control completely. Usually these programs
4534 will install their own set of exception handlers, device
4535 drivers, set up the MMU, etc. - this means, that you cannot
4536 expect to re-enter U-Boot except by resetting the CPU.
4537 "RAMDisk Images" are more or less just data blocks, and their
4538 parameters (address, size) are passed to an OS kernel that is
4539 being started.
4540 "Multi-File Images" contain several images, typically an OS
4541 (Linux) kernel image and one or more data images like
4542 RAMDisks. This construct is useful for instance when you want
4543 to boot over the network using BOOTP etc., where the boot
4544 server provides just a single image file, but you want to get
4545 for instance an OS kernel and a RAMDisk image.
stroesec1551ea2003-04-04 15:53:41 +00004546
wdenk2729af92004-05-03 20:45:30 +00004547 "Multi-File Images" start with a list of image sizes, each
4548 image size (in bytes) specified by an "uint32_t" in network
4549 byte order. This list is terminated by an "(uint32_t)0".
4550 Immediately after the terminating 0 follow the images, one by
4551 one, all aligned on "uint32_t" boundaries (size rounded up to
4552 a multiple of 4 bytes).
stroesec1551ea2003-04-04 15:53:41 +00004553
wdenk2729af92004-05-03 20:45:30 +00004554 "Firmware Images" are binary images containing firmware (like
4555 U-Boot or FPGA images) which usually will be programmed to
4556 flash memory.
stroesec1551ea2003-04-04 15:53:41 +00004557
wdenk2729af92004-05-03 20:45:30 +00004558 "Script files" are command sequences that will be executed by
4559 U-Boot's command interpreter; this feature is especially
4560 useful when you configure U-Boot to use a real shell (hush)
4561 as command interpreter.
wdenk6069ff22003-02-28 00:49:47 +00004562
Marek Vasut44f074c2012-03-14 21:52:45 +00004563Booting the Linux zImage:
4564-------------------------
4565
4566On some platforms, it's possible to boot Linux zImage. This is done
4567using the "bootz" command. The syntax of "bootz" command is the same
4568as the syntax of "bootm" command.
4569
Tom Rini8ac28562013-05-16 11:40:11 -04004570Note, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply
Marek Vasut017e1f32012-03-18 11:47:58 +00004571kernel with raw initrd images. The syntax is slightly different, the
4572address of the initrd must be augmented by it's size, in the following
4573format: "<initrd addres>:<initrd size>".
4574
wdenkc6097192002-11-03 00:24:07 +00004575
wdenk2729af92004-05-03 20:45:30 +00004576Standalone HOWTO:
4577=================
wdenkc6097192002-11-03 00:24:07 +00004578
wdenk2729af92004-05-03 20:45:30 +00004579One of the features of U-Boot is that you can dynamically load and
4580run "standalone" applications, which can use some resources of
4581U-Boot like console I/O functions or interrupt services.
wdenkc6097192002-11-03 00:24:07 +00004582
wdenk2729af92004-05-03 20:45:30 +00004583Two simple examples are included with the sources:
wdenkc6097192002-11-03 00:24:07 +00004584
wdenk2729af92004-05-03 20:45:30 +00004585"Hello World" Demo:
4586-------------------
wdenkc6097192002-11-03 00:24:07 +00004587
wdenk2729af92004-05-03 20:45:30 +00004588'examples/hello_world.c' contains a small "Hello World" Demo
4589application; it is automatically compiled when you build U-Boot.
4590It's configured to run at address 0x00040004, so you can play with it
4591like that:
wdenkc6097192002-11-03 00:24:07 +00004592
wdenk2729af92004-05-03 20:45:30 +00004593 => loads
4594 ## Ready for S-Record download ...
4595 ~>examples/hello_world.srec
4596 1 2 3 4 5 6 7 8 9 10 11 ...
4597 [file transfer complete]
4598 [connected]
4599 ## Start Addr = 0x00040004
wdenkc6097192002-11-03 00:24:07 +00004600
wdenk2729af92004-05-03 20:45:30 +00004601 => go 40004 Hello World! This is a test.
4602 ## Starting application at 0x00040004 ...
4603 Hello World
4604 argc = 7
4605 argv[0] = "40004"
4606 argv[1] = "Hello"
4607 argv[2] = "World!"
4608 argv[3] = "This"
4609 argv[4] = "is"
4610 argv[5] = "a"
4611 argv[6] = "test."
4612 argv[7] = "<NULL>"
4613 Hit any key to exit ...
wdenkc6097192002-11-03 00:24:07 +00004614
wdenk2729af92004-05-03 20:45:30 +00004615 ## Application terminated, rc = 0x0
wdenkc6097192002-11-03 00:24:07 +00004616
wdenk2729af92004-05-03 20:45:30 +00004617Another example, which demonstrates how to register a CPM interrupt
4618handler with the U-Boot code, can be found in 'examples/timer.c'.
4619Here, a CPM timer is set up to generate an interrupt every second.
4620The interrupt service routine is trivial, just printing a '.'
4621character, but this is just a demo program. The application can be
4622controlled by the following keys:
wdenkc6097192002-11-03 00:24:07 +00004623
wdenk2729af92004-05-03 20:45:30 +00004624 ? - print current values og the CPM Timer registers
4625 b - enable interrupts and start timer
4626 e - stop timer and disable interrupts
4627 q - quit application
wdenkc6097192002-11-03 00:24:07 +00004628
wdenk2729af92004-05-03 20:45:30 +00004629 => loads
4630 ## Ready for S-Record download ...
4631 ~>examples/timer.srec
4632 1 2 3 4 5 6 7 8 9 10 11 ...
4633 [file transfer complete]
4634 [connected]
4635 ## Start Addr = 0x00040004
wdenkc6097192002-11-03 00:24:07 +00004636
wdenk2729af92004-05-03 20:45:30 +00004637 => go 40004
4638 ## Starting application at 0x00040004 ...
4639 TIMERS=0xfff00980
4640 Using timer 1
4641 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
wdenkc6097192002-11-03 00:24:07 +00004642
wdenk2729af92004-05-03 20:45:30 +00004643Hit 'b':
4644 [q, b, e, ?] Set interval 1000000 us
4645 Enabling timer
4646Hit '?':
4647 [q, b, e, ?] ........
4648 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
4649Hit '?':
4650 [q, b, e, ?] .
4651 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
4652Hit '?':
4653 [q, b, e, ?] .
4654 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
4655Hit '?':
4656 [q, b, e, ?] .
4657 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
4658Hit 'e':
4659 [q, b, e, ?] ...Stopping timer
4660Hit 'q':
4661 [q, b, e, ?] ## Application terminated, rc = 0x0
wdenkc6097192002-11-03 00:24:07 +00004662
4663
wdenk2729af92004-05-03 20:45:30 +00004664Minicom warning:
4665================
wdenk85ec0bc2003-03-31 16:34:49 +00004666
wdenk2729af92004-05-03 20:45:30 +00004667Over time, many people have reported problems when trying to use the
4668"minicom" terminal emulation program for serial download. I (wd)
4669consider minicom to be broken, and recommend not to use it. Under
4670Unix, I recommend to use C-Kermit for general purpose use (and
4671especially for kermit binary protocol download ("loadb" command), and
Karl O. Pince53515a2012-10-01 05:11:56 +00004672use "cu" for S-Record download ("loads" command). See
4673http://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3.
4674for help with kermit.
4675
wdenk85ec0bc2003-03-31 16:34:49 +00004676
wdenk2729af92004-05-03 20:45:30 +00004677Nevertheless, if you absolutely want to use it try adding this
4678configuration to your "File transfer protocols" section:
wdenk52f52c12003-06-19 23:04:19 +00004679
wdenk2729af92004-05-03 20:45:30 +00004680 Name Program Name U/D FullScr IO-Red. Multi
4681 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
4682 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
wdenk52f52c12003-06-19 23:04:19 +00004683
4684
wdenk2729af92004-05-03 20:45:30 +00004685NetBSD Notes:
4686=============
wdenkc6097192002-11-03 00:24:07 +00004687
wdenk2729af92004-05-03 20:45:30 +00004688Starting at version 0.9.2, U-Boot supports NetBSD both as host
4689(build U-Boot) and target system (boots NetBSD/mpc8xx).
wdenkc6097192002-11-03 00:24:07 +00004690
wdenk2729af92004-05-03 20:45:30 +00004691Building requires a cross environment; it is known to work on
4692NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
4693need gmake since the Makefiles are not compatible with BSD make).
4694Note that the cross-powerpc package does not install include files;
4695attempting to build U-Boot will fail because <machine/ansi.h> is
4696missing. This file has to be installed and patched manually:
wdenkc6097192002-11-03 00:24:07 +00004697
wdenk2729af92004-05-03 20:45:30 +00004698 # cd /usr/pkg/cross/powerpc-netbsd/include
4699 # mkdir powerpc
4700 # ln -s powerpc machine
4701 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
4702 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
wdenkc6097192002-11-03 00:24:07 +00004703
wdenk2729af92004-05-03 20:45:30 +00004704Native builds *don't* work due to incompatibilities between native
4705and U-Boot include files.
wdenkc6097192002-11-03 00:24:07 +00004706
wdenk2729af92004-05-03 20:45:30 +00004707Booting assumes that (the first part of) the image booted is a
4708stage-2 loader which in turn loads and then invokes the kernel
4709proper. Loader sources will eventually appear in the NetBSD source
4710tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
wdenk2a8af182005-04-13 10:02:42 +00004711meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
wdenkc6097192002-11-03 00:24:07 +00004712
4713
wdenk2729af92004-05-03 20:45:30 +00004714Implementation Internals:
4715=========================
wdenkc6097192002-11-03 00:24:07 +00004716
wdenk2729af92004-05-03 20:45:30 +00004717The following is not intended to be a complete description of every
4718implementation detail. However, it should help to understand the
4719inner workings of U-Boot and make it easier to port it to custom
4720hardware.
wdenkc6097192002-11-03 00:24:07 +00004721
4722
wdenk2729af92004-05-03 20:45:30 +00004723Initial Stack, Global Data:
4724---------------------------
wdenkc6097192002-11-03 00:24:07 +00004725
wdenk2729af92004-05-03 20:45:30 +00004726The implementation of U-Boot is complicated by the fact that U-Boot
4727starts running out of ROM (flash memory), usually without access to
4728system RAM (because the memory controller is not initialized yet).
4729This means that we don't have writable Data or BSS segments, and BSS
4730is not initialized as zero. To be able to get a C environment working
4731at all, we have to allocate at least a minimal stack. Implementation
4732options for this are defined and restricted by the CPU used: Some CPU
4733models provide on-chip memory (like the IMMR area on MPC8xx and
4734MPC826x processors), on others (parts of) the data cache can be
4735locked as (mis-) used as memory, etc.
wdenkc6097192002-11-03 00:24:07 +00004736
Wolfgang Denk218ca722008-03-26 10:40:12 +01004737 Chris Hallinan posted a good summary of these issues to the
Wolfgang Denk06682362008-12-30 22:56:11 +01004738 U-Boot mailing list:
wdenk43d96162003-03-06 00:02:04 +00004739
wdenk2729af92004-05-03 20:45:30 +00004740 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
4741 From: "Chris Hallinan" <clh@net1plus.com>
4742 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
4743 ...
wdenk43d96162003-03-06 00:02:04 +00004744
wdenk2729af92004-05-03 20:45:30 +00004745 Correct me if I'm wrong, folks, but the way I understand it
4746 is this: Using DCACHE as initial RAM for Stack, etc, does not
4747 require any physical RAM backing up the cache. The cleverness
4748 is that the cache is being used as a temporary supply of
4749 necessary storage before the SDRAM controller is setup. It's
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02004750 beyond the scope of this list to explain the details, but you
wdenk2729af92004-05-03 20:45:30 +00004751 can see how this works by studying the cache architecture and
4752 operation in the architecture and processor-specific manuals.
wdenk43d96162003-03-06 00:02:04 +00004753
wdenk2729af92004-05-03 20:45:30 +00004754 OCM is On Chip Memory, which I believe the 405GP has 4K. It
4755 is another option for the system designer to use as an
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02004756 initial stack/RAM area prior to SDRAM being available. Either
wdenk2729af92004-05-03 20:45:30 +00004757 option should work for you. Using CS 4 should be fine if your
4758 board designers haven't used it for something that would
4759 cause you grief during the initial boot! It is frequently not
4760 used.
wdenk43d96162003-03-06 00:02:04 +00004761
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02004762 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere
wdenk2729af92004-05-03 20:45:30 +00004763 with your processor/board/system design. The default value
4764 you will find in any recent u-boot distribution in
Stefan Roese8a316c92005-08-01 16:49:12 +02004765 walnut.h should work for you. I'd set it to a value larger
wdenk2729af92004-05-03 20:45:30 +00004766 than your SDRAM module. If you have a 64MB SDRAM module, set
4767 it above 400_0000. Just make sure your board has no resources
4768 that are supposed to respond to that address! That code in
4769 start.S has been around a while and should work as is when
4770 you get the config right.
wdenk43d96162003-03-06 00:02:04 +00004771
wdenk2729af92004-05-03 20:45:30 +00004772 -Chris Hallinan
4773 DS4.COM, Inc.
wdenk43d96162003-03-06 00:02:04 +00004774
wdenk2729af92004-05-03 20:45:30 +00004775It is essential to remember this, since it has some impact on the C
4776code for the initialization procedures:
wdenkc6097192002-11-03 00:24:07 +00004777
wdenk2729af92004-05-03 20:45:30 +00004778* Initialized global data (data segment) is read-only. Do not attempt
4779 to write it.
wdenkc6097192002-11-03 00:24:07 +00004780
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08004781* Do not use any uninitialized global data (or implicitly initialized
wdenk2729af92004-05-03 20:45:30 +00004782 as zero data - BSS segment) at all - this is undefined, initiali-
4783 zation is performed later (when relocating to RAM).
wdenkc6097192002-11-03 00:24:07 +00004784
wdenk2729af92004-05-03 20:45:30 +00004785* Stack space is very limited. Avoid big data buffers or things like
4786 that.
wdenkc6097192002-11-03 00:24:07 +00004787
wdenk2729af92004-05-03 20:45:30 +00004788Having only the stack as writable memory limits means we cannot use
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08004789normal global data to share information between the code. But it
wdenk2729af92004-05-03 20:45:30 +00004790turned out that the implementation of U-Boot can be greatly
4791simplified by making a global data structure (gd_t) available to all
4792functions. We could pass a pointer to this data as argument to _all_
4793functions, but this would bloat the code. Instead we use a feature of
4794the GCC compiler (Global Register Variables) to share the data: we
4795place a pointer (gd) to the global data into a register which we
4796reserve for this purpose.
wdenkc6097192002-11-03 00:24:07 +00004797
wdenk2729af92004-05-03 20:45:30 +00004798When choosing a register for such a purpose we are restricted by the
4799relevant (E)ABI specifications for the current architecture, and by
4800GCC's implementation.
wdenkc6097192002-11-03 00:24:07 +00004801
wdenk2729af92004-05-03 20:45:30 +00004802For PowerPC, the following registers have specific use:
4803 R1: stack pointer
Wolfgang Denke7670f62008-02-14 22:43:22 +01004804 R2: reserved for system use
wdenk2729af92004-05-03 20:45:30 +00004805 R3-R4: parameter passing and return values
4806 R5-R10: parameter passing
4807 R13: small data area pointer
4808 R30: GOT pointer
4809 R31: frame pointer
wdenkc6097192002-11-03 00:24:07 +00004810
Joakim Tjernlunde6bee802010-01-19 14:41:58 +01004811 (U-Boot also uses R12 as internal GOT pointer. r12
4812 is a volatile register so r12 needs to be reset when
4813 going back and forth between asm and C)
wdenkc6097192002-11-03 00:24:07 +00004814
Wolfgang Denke7670f62008-02-14 22:43:22 +01004815 ==> U-Boot will use R2 to hold a pointer to the global data
wdenkc6097192002-11-03 00:24:07 +00004816
wdenk2729af92004-05-03 20:45:30 +00004817 Note: on PPC, we could use a static initializer (since the
4818 address of the global data structure is known at compile time),
4819 but it turned out that reserving a register results in somewhat
4820 smaller code - although the code savings are not that big (on
4821 average for all boards 752 bytes for the whole U-Boot image,
4822 624 text + 127 data).
wdenkc6097192002-11-03 00:24:07 +00004823
wdenk2729af92004-05-03 20:45:30 +00004824On ARM, the following registers are used:
wdenkc6097192002-11-03 00:24:07 +00004825
wdenk2729af92004-05-03 20:45:30 +00004826 R0: function argument word/integer result
4827 R1-R3: function argument word
Jeroen Hofstee12eba1b2013-09-21 14:04:42 +02004828 R9: platform specific
4829 R10: stack limit (used only if stack checking is enabled)
wdenk2729af92004-05-03 20:45:30 +00004830 R11: argument (frame) pointer
4831 R12: temporary workspace
4832 R13: stack pointer
4833 R14: link register
4834 R15: program counter
wdenkc6097192002-11-03 00:24:07 +00004835
Jeroen Hofstee12eba1b2013-09-21 14:04:42 +02004836 ==> U-Boot will use R9 to hold a pointer to the global data
4837
4838 Note: on ARM, only R_ARM_RELATIVE relocations are supported.
wdenkc6097192002-11-03 00:24:07 +00004839
Thomas Chou0df01fd2010-05-21 11:08:03 +08004840On Nios II, the ABI is documented here:
4841 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf
4842
4843 ==> U-Boot will use gp to hold a pointer to the global data
4844
4845 Note: on Nios II, we give "-G0" option to gcc and don't use gp
4846 to access small data sections, so gp is free.
4847
Macpaul Linafc1ce82011-10-19 20:41:11 +00004848On NDS32, the following registers are used:
4849
4850 R0-R1: argument/return
4851 R2-R5: argument
4852 R15: temporary register for assembler
4853 R16: trampoline register
4854 R28: frame pointer (FP)
4855 R29: global pointer (GP)
4856 R30: link register (LP)
4857 R31: stack pointer (SP)
4858 PC: program counter (PC)
4859
4860 ==> U-Boot will use R10 to hold a pointer to the global data
4861
Wolfgang Denkd87080b2006-03-31 18:32:53 +02004862NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
4863or current versions of GCC may "optimize" the code too much.
wdenkc6097192002-11-03 00:24:07 +00004864
Rick Chen3fafced2017-12-26 13:55:59 +08004865On RISC-V, the following registers are used:
4866
4867 x0: hard-wired zero (zero)
4868 x1: return address (ra)
4869 x2: stack pointer (sp)
4870 x3: global pointer (gp)
4871 x4: thread pointer (tp)
4872 x5: link register (t0)
4873 x8: frame pointer (fp)
4874 x10-x11: arguments/return values (a0-1)
4875 x12-x17: arguments (a2-7)
4876 x28-31: temporaries (t3-6)
4877 pc: program counter (pc)
4878
4879 ==> U-Boot will use gp to hold a pointer to the global data
4880
wdenk2729af92004-05-03 20:45:30 +00004881Memory Management:
4882------------------
wdenkc6097192002-11-03 00:24:07 +00004883
wdenk2729af92004-05-03 20:45:30 +00004884U-Boot runs in system state and uses physical addresses, i.e. the
4885MMU is not used either for address mapping nor for memory protection.
wdenkc6097192002-11-03 00:24:07 +00004886
wdenk2729af92004-05-03 20:45:30 +00004887The available memory is mapped to fixed addresses using the memory
4888controller. In this process, a contiguous block is formed for each
4889memory type (Flash, SDRAM, SRAM), even when it consists of several
4890physical memory banks.
wdenkc6097192002-11-03 00:24:07 +00004891
wdenk2729af92004-05-03 20:45:30 +00004892U-Boot is installed in the first 128 kB of the first Flash bank (on
4893TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
4894booting and sizing and initializing DRAM, the code relocates itself
4895to the upper end of DRAM. Immediately below the U-Boot code some
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02004896memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN
wdenk2729af92004-05-03 20:45:30 +00004897configuration setting]. Below that, a structure with global Board
4898Info data is placed, followed by the stack (growing downward).
wdenkc6097192002-11-03 00:24:07 +00004899
wdenk2729af92004-05-03 20:45:30 +00004900Additionally, some exception handler code is copied to the low 8 kB
4901of DRAM (0x00000000 ... 0x00001FFF).
wdenkc6097192002-11-03 00:24:07 +00004902
wdenk2729af92004-05-03 20:45:30 +00004903So a typical memory configuration with 16 MB of DRAM could look like
4904this:
wdenkc6097192002-11-03 00:24:07 +00004905
wdenk2729af92004-05-03 20:45:30 +00004906 0x0000 0000 Exception Vector code
4907 :
4908 0x0000 1FFF
4909 0x0000 2000 Free for Application Use
4910 :
4911 :
wdenkc6097192002-11-03 00:24:07 +00004912
wdenk2729af92004-05-03 20:45:30 +00004913 :
4914 :
4915 0x00FB FF20 Monitor Stack (Growing downward)
4916 0x00FB FFAC Board Info Data and permanent copy of global data
4917 0x00FC 0000 Malloc Arena
4918 :
4919 0x00FD FFFF
4920 0x00FE 0000 RAM Copy of Monitor Code
4921 ... eventually: LCD or video framebuffer
4922 ... eventually: pRAM (Protected RAM - unchanged by reset)
4923 0x00FF FFFF [End of RAM]
wdenkc6097192002-11-03 00:24:07 +00004924
4925
wdenk2729af92004-05-03 20:45:30 +00004926System Initialization:
4927----------------------
wdenkc6097192002-11-03 00:24:07 +00004928
wdenk2729af92004-05-03 20:45:30 +00004929In the reset configuration, U-Boot starts at the reset entry point
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02004930(on most PowerPC systems at address 0x00000100). Because of the reset
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08004931configuration for CS0# this is a mirror of the on board Flash memory.
wdenk2729af92004-05-03 20:45:30 +00004932To be able to re-map memory U-Boot then jumps to its link address.
4933To be able to implement the initialization code in C, a (small!)
4934initial stack is set up in the internal Dual Ported RAM (in case CPUs
Heiko Schocher2eb48ff2017-06-07 17:33:10 +02004935which provide such a feature like), or in a locked part of the data
4936cache. After that, U-Boot initializes the CPU core, the caches and
4937the SIU.
wdenkc6097192002-11-03 00:24:07 +00004938
wdenk2729af92004-05-03 20:45:30 +00004939Next, all (potentially) available memory banks are mapped using a
4940preliminary mapping. For example, we put them on 512 MB boundaries
4941(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
4942on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
4943programmed for SDRAM access. Using the temporary configuration, a
4944simple memory test is run that determines the size of the SDRAM
4945banks.
wdenkc6097192002-11-03 00:24:07 +00004946
wdenk2729af92004-05-03 20:45:30 +00004947When there is more than one SDRAM bank, and the banks are of
4948different size, the largest is mapped first. For equal size, the first
4949bank (CS2#) is mapped first. The first mapping is always for address
49500x00000000, with any additional banks following immediately to create
4951contiguous memory starting from 0.
wdenkc6097192002-11-03 00:24:07 +00004952
wdenk2729af92004-05-03 20:45:30 +00004953Then, the monitor installs itself at the upper end of the SDRAM area
4954and allocates memory for use by malloc() and for the global Board
4955Info data; also, the exception vector code is copied to the low RAM
4956pages, and the final stack is set up.
wdenkc6097192002-11-03 00:24:07 +00004957
wdenk2729af92004-05-03 20:45:30 +00004958Only after this relocation will you have a "normal" C environment;
4959until that you are restricted in several ways, mostly because you are
4960running from ROM, and because the code will have to be relocated to a
4961new address in RAM.
wdenkc6097192002-11-03 00:24:07 +00004962
4963
wdenk2729af92004-05-03 20:45:30 +00004964U-Boot Porting Guide:
4965----------------------
wdenkc6097192002-11-03 00:24:07 +00004966
wdenk2729af92004-05-03 20:45:30 +00004967[Based on messages by Jerry Van Baren in the U-Boot-Users mailing
4968list, October 2002]
wdenkc6097192002-11-03 00:24:07 +00004969
4970
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04004971int main(int argc, char *argv[])
wdenk2729af92004-05-03 20:45:30 +00004972{
4973 sighandler_t no_more_time;
wdenkc6097192002-11-03 00:24:07 +00004974
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04004975 signal(SIGALRM, no_more_time);
4976 alarm(PROJECT_DEADLINE - toSec (3 * WEEK));
wdenkc6097192002-11-03 00:24:07 +00004977
wdenk2729af92004-05-03 20:45:30 +00004978 if (available_money > available_manpower) {
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04004979 Pay consultant to port U-Boot;
wdenkc6097192002-11-03 00:24:07 +00004980 return 0;
4981 }
4982
wdenk2729af92004-05-03 20:45:30 +00004983 Download latest U-Boot source;
4984
Wolfgang Denk06682362008-12-30 22:56:11 +01004985 Subscribe to u-boot mailing list;
wdenk2729af92004-05-03 20:45:30 +00004986
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04004987 if (clueless)
4988 email("Hi, I am new to U-Boot, how do I get started?");
wdenkc6097192002-11-03 00:24:07 +00004989
wdenk2729af92004-05-03 20:45:30 +00004990 while (learning) {
4991 Read the README file in the top level directory;
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04004992 Read http://www.denx.de/twiki/bin/view/DULG/Manual;
4993 Read applicable doc/*.README;
wdenk2729af92004-05-03 20:45:30 +00004994 Read the source, Luke;
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04004995 /* find . -name "*.[chS]" | xargs grep -i <keyword> */
wdenk2729af92004-05-03 20:45:30 +00004996 }
wdenkc6097192002-11-03 00:24:07 +00004997
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04004998 if (available_money > toLocalCurrency ($2500))
4999 Buy a BDI3000;
5000 else
wdenk2729af92004-05-03 20:45:30 +00005001 Add a lot of aggravation and time;
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04005002
5003 if (a similar board exists) { /* hopefully... */
5004 cp -a board/<similar> board/<myboard>
5005 cp include/configs/<similar>.h include/configs/<myboard>.h
5006 } else {
5007 Create your own board support subdirectory;
5008 Create your own board include/configs/<myboard>.h file;
wdenk2729af92004-05-03 20:45:30 +00005009 }
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04005010 Edit new board/<myboard> files
5011 Edit new include/configs/<myboard>.h
wdenkc6097192002-11-03 00:24:07 +00005012
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04005013 while (!accepted) {
5014 while (!running) {
5015 do {
5016 Add / modify source code;
5017 } until (compiles);
5018 Debug;
5019 if (clueless)
5020 email("Hi, I am having problems...");
5021 }
5022 Send patch file to the U-Boot email list;
5023 if (reasonable critiques)
5024 Incorporate improvements from email list code review;
5025 else
5026 Defend code as written;
wdenk2729af92004-05-03 20:45:30 +00005027 }
wdenkc6097192002-11-03 00:24:07 +00005028
wdenk2729af92004-05-03 20:45:30 +00005029 return 0;
5030}
5031
5032void no_more_time (int sig)
5033{
5034 hire_a_guru();
5035}
wdenkc6097192002-11-03 00:24:07 +00005036
5037
wdenk2729af92004-05-03 20:45:30 +00005038Coding Standards:
5039-----------------
wdenkc6097192002-11-03 00:24:07 +00005040
wdenk2729af92004-05-03 20:45:30 +00005041All contributions to U-Boot should conform to the Linux kernel
Baruch Siach659208d2017-12-10 17:34:35 +02005042coding style; see the kernel coding style guide at
5043https://www.kernel.org/doc/html/latest/process/coding-style.html, and the
5044script "scripts/Lindent" in your Linux kernel source directory.
wdenk2729af92004-05-03 20:45:30 +00005045
Detlev Zundel2c051652006-09-01 15:39:02 +02005046Source files originating from a different project (for example the
5047MTD subsystem) are generally exempt from these guidelines and are not
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08005048reformatted to ease subsequent migration to newer versions of those
Detlev Zundel2c051652006-09-01 15:39:02 +02005049sources.
5050
5051Please note that U-Boot is implemented in C (and to some small parts in
5052Assembler); no C++ is used, so please do not use C++ style comments (//)
5053in your code.
wdenk2729af92004-05-03 20:45:30 +00005054
5055Please also stick to the following formatting rules:
5056- remove any trailing white space
Wolfgang Denk7ca92962011-07-27 10:59:55 +00005057- use TAB characters for indentation and vertical alignment, not spaces
wdenk2729af92004-05-03 20:45:30 +00005058- make sure NOT to use DOS '\r\n' line feeds
Wolfgang Denk7ca92962011-07-27 10:59:55 +00005059- do not add more than 2 consecutive empty lines to source files
wdenk2729af92004-05-03 20:45:30 +00005060- do not add trailing empty lines to source files
5061
5062Submissions which do not conform to the standards may be returned
5063with a request to reformat the changes.
wdenkc6097192002-11-03 00:24:07 +00005064
5065
wdenk2729af92004-05-03 20:45:30 +00005066Submitting Patches:
5067-------------------
wdenkc6097192002-11-03 00:24:07 +00005068
wdenk2729af92004-05-03 20:45:30 +00005069Since the number of patches for U-Boot is growing, we need to
5070establish some rules. Submissions which do not conform to these rules
5071may be rejected, even when they contain important and valuable stuff.
wdenkc6097192002-11-03 00:24:07 +00005072
Magnus Lilja0d28f342008-08-06 19:32:33 +02005073Please see http://www.denx.de/wiki/U-Boot/Patches for details.
Wolfgang Denk218ca722008-03-26 10:40:12 +01005074
Wolfgang Denk06682362008-12-30 22:56:11 +01005075Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>;
S. Lockwood-Childs1dade182017-11-14 22:56:42 -08005076see https://lists.denx.de/listinfo/u-boot
Wolfgang Denk06682362008-12-30 22:56:11 +01005077
wdenk2729af92004-05-03 20:45:30 +00005078When you send a patch, please include the following information with
5079it:
wdenkc6097192002-11-03 00:24:07 +00005080
wdenk2729af92004-05-03 20:45:30 +00005081* For bug fixes: a description of the bug and how your patch fixes
5082 this bug. Please try to include a way of demonstrating that the
5083 patch actually fixes something.
wdenkc6097192002-11-03 00:24:07 +00005084
wdenk2729af92004-05-03 20:45:30 +00005085* For new features: a description of the feature and your
5086 implementation.
wdenkc6097192002-11-03 00:24:07 +00005087
wdenk2729af92004-05-03 20:45:30 +00005088* A CHANGELOG entry as plaintext (separate from the patch)
5089
Robert P. J. Day7207b362015-12-19 07:16:10 -05005090* For major contributions, add a MAINTAINERS file with your
5091 information and associated file and directory references.
wdenk2729af92004-05-03 20:45:30 +00005092
Albert ARIBAUD27af9302013-09-11 15:52:51 +02005093* When you add support for a new board, don't forget to add a
5094 maintainer e-mail address to the boards.cfg file, too.
wdenk2729af92004-05-03 20:45:30 +00005095
5096* If your patch adds new configuration options, don't forget to
5097 document these in the README file.
5098
Wolfgang Denk218ca722008-03-26 10:40:12 +01005099* The patch itself. If you are using git (which is *strongly*
5100 recommended) you can easily generate the patch using the
Wolfgang Denk7ca92962011-07-27 10:59:55 +00005101 "git format-patch". If you then use "git send-email" to send it to
Wolfgang Denk218ca722008-03-26 10:40:12 +01005102 the U-Boot mailing list, you will avoid most of the common problems
5103 with some other mail clients.
wdenk2729af92004-05-03 20:45:30 +00005104
Wolfgang Denk218ca722008-03-26 10:40:12 +01005105 If you cannot use git, use "diff -purN OLD NEW". If your version of
5106 diff does not support these options, then get the latest version of
5107 GNU diff.
wdenk2729af92004-05-03 20:45:30 +00005108
Wolfgang Denk218ca722008-03-26 10:40:12 +01005109 The current directory when running this command shall be the parent
5110 directory of the U-Boot source tree (i. e. please make sure that
5111 your patch includes sufficient directory information for the
5112 affected files).
5113
5114 We prefer patches as plain text. MIME attachments are discouraged,
5115 and compressed attachments must not be used.
wdenk2729af92004-05-03 20:45:30 +00005116
5117* If one logical set of modifications affects or creates several
5118 files, all these changes shall be submitted in a SINGLE patch file.
5119
5120* Changesets that contain different, unrelated modifications shall be
5121 submitted as SEPARATE patches, one patch per changeset.
5122
5123
5124Notes:
5125
Simon Glass6de80f22016-07-27 20:33:08 -06005126* Before sending the patch, run the buildman script on your patched
wdenk2729af92004-05-03 20:45:30 +00005127 source tree and make sure that no errors or warnings are reported
5128 for any of the boards.
5129
5130* Keep your modifications to the necessary minimum: A patch
5131 containing several unrelated changes or arbitrary reformats will be
5132 returned with a request to re-formatting / split it.
5133
5134* If you modify existing code, make sure that your new code does not
5135 add to the memory footprint of the code ;-) Small is beautiful!
5136 When adding new features, these should compile conditionally only
5137 (using #ifdef), and the resulting code with the new feature
5138 disabled must not need more memory than the old code without your
5139 modification.
wdenk90dc6702005-05-03 14:12:25 +00005140
Wolfgang Denk06682362008-12-30 22:56:11 +01005141* Remember that there is a size limit of 100 kB per message on the
5142 u-boot mailing list. Bigger patches will be moderated. If they are
5143 reasonable and not too big, they will be acknowledged. But patches
5144 bigger than the size limit should be avoided.