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Tom Rini83d290c2018-05-06 17:58:06 -04001# SPDX-License-Identifier: GPL-2.0+
wdenkc6097192002-11-03 00:24:07 +00002#
Wolfgang Denkeca3aeb2013-06-21 10:22:36 +02003# (C) Copyright 2000 - 2013
wdenkc6097192002-11-03 00:24:07 +00004# Wolfgang Denk, DENX Software Engineering, wd@denx.de.
wdenkc6097192002-11-03 00:24:07 +00005
6Summary:
7========
8
wdenk24ee89b2002-11-03 17:56:27 +00009This directory contains the source code for U-Boot, a boot loader for
wdenke86e5a02004-10-17 21:12:06 +000010Embedded boards based on PowerPC, ARM, MIPS and several other
11processors, which can be installed in a boot ROM and used to
12initialize and test the hardware or to download and run application
13code.
wdenkc6097192002-11-03 00:24:07 +000014
15The development of U-Boot is closely related to Linux: some parts of
wdenk24ee89b2002-11-03 17:56:27 +000016the source code originate in the Linux source tree, we have some
17header files in common, and special provision has been made to
wdenkc6097192002-11-03 00:24:07 +000018support booting of Linux images.
19
20Some attention has been paid to make this software easily
21configurable and extendable. For instance, all monitor commands are
22implemented with the same call interface, so that it's very easy to
23add new commands. Also, instead of permanently adding rarely used
24code (for instance hardware test utilities) to the monitor, you can
25load and run it dynamically.
26
27
28Status:
29=======
30
31In general, all boards for which a configuration option exists in the
wdenk24ee89b2002-11-03 17:56:27 +000032Makefile have been tested to some extent and can be considered
wdenkc6097192002-11-03 00:24:07 +000033"working". In fact, many of them are used in production systems.
34
Robert P. J. Day7207b362015-12-19 07:16:10 -050035In case of problems see the CHANGELOG file to find out who contributed
36the specific port. In addition, there are various MAINTAINERS files
37scattered throughout the U-Boot source identifying the people or
38companies responsible for various boards and subsystems.
wdenkc6097192002-11-03 00:24:07 +000039
Robert P. J. Day7207b362015-12-19 07:16:10 -050040Note: As of August, 2010, there is no longer a CHANGELOG file in the
41actual U-Boot source tree; however, it can be created dynamically
42from the Git log using:
Robert P. J. Dayadb9d852012-11-14 02:03:20 +000043
44 make CHANGELOG
45
wdenkc6097192002-11-03 00:24:07 +000046
47Where to get help:
48==================
49
wdenk24ee89b2002-11-03 17:56:27 +000050In case you have questions about, problems with or contributions for
Robert P. J. Day7207b362015-12-19 07:16:10 -050051U-Boot, you should send a message to the U-Boot mailing list at
Peter Tyser0c325652008-09-10 09:18:34 -050052<u-boot@lists.denx.de>. There is also an archive of previous traffic
53on the mailing list - please search the archive before asking FAQ's.
54Please see http://lists.denx.de/pipermail/u-boot and
55http://dir.gmane.org/gmane.comp.boot-loaders.u-boot
wdenkc6097192002-11-03 00:24:07 +000056
57
Wolfgang Denk218ca722008-03-26 10:40:12 +010058Where to get source code:
59=========================
60
Robert P. J. Day7207b362015-12-19 07:16:10 -050061The U-Boot source code is maintained in the Git repository at
Wolfgang Denk218ca722008-03-26 10:40:12 +010062git://www.denx.de/git/u-boot.git ; you can browse it online at
63http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary
64
65The "snapshot" links on this page allow you to download tarballs of
Marcel Ziswiler11ccc332008-07-09 08:17:15 +020066any version you might be interested in. Official releases are also
Wolfgang Denk218ca722008-03-26 10:40:12 +010067available for FTP download from the ftp://ftp.denx.de/pub/u-boot/
68directory.
69
Anatolij Gustschind4ee7112008-03-26 18:13:33 +010070Pre-built (and tested) images are available from
Wolfgang Denk218ca722008-03-26 10:40:12 +010071ftp://ftp.denx.de/pub/u-boot/images/
72
73
wdenkc6097192002-11-03 00:24:07 +000074Where we come from:
75===================
76
77- start from 8xxrom sources
wdenk24ee89b2002-11-03 17:56:27 +000078- create PPCBoot project (http://sourceforge.net/projects/ppcboot)
wdenkc6097192002-11-03 00:24:07 +000079- clean up code
80- make it easier to add custom boards
81- make it possible to add other [PowerPC] CPUs
82- extend functions, especially:
83 * Provide extended interface to Linux boot loader
84 * S-Record download
85 * network boot
Marcel Ziswiler11ccc332008-07-09 08:17:15 +020086 * PCMCIA / CompactFlash / ATA disk / SCSI ... boot
wdenk24ee89b2002-11-03 17:56:27 +000087- create ARMBoot project (http://sourceforge.net/projects/armboot)
wdenkc6097192002-11-03 00:24:07 +000088- add other CPU families (starting with ARM)
wdenk24ee89b2002-11-03 17:56:27 +000089- create U-Boot project (http://sourceforge.net/projects/u-boot)
Magnus Lilja0d28f342008-08-06 19:32:33 +020090- current project page: see http://www.denx.de/wiki/U-Boot
wdenk24ee89b2002-11-03 17:56:27 +000091
92
93Names and Spelling:
94===================
95
96The "official" name of this project is "Das U-Boot". The spelling
97"U-Boot" shall be used in all written text (documentation, comments
98in source files etc.). Example:
99
100 This is the README file for the U-Boot project.
101
102File names etc. shall be based on the string "u-boot". Examples:
103
104 include/asm-ppc/u-boot.h
105
106 #include <asm/u-boot.h>
107
108Variable names, preprocessor constants etc. shall be either based on
109the string "u_boot" or on "U_BOOT". Example:
110
111 U_BOOT_VERSION u_boot_logo
112 IH_OS_U_BOOT u_boot_hush_start
wdenkc6097192002-11-03 00:24:07 +0000113
114
wdenk93f19cc2002-12-17 17:55:09 +0000115Versioning:
116===========
117
Thomas Weber360d8832010-09-28 08:06:25 +0200118Starting with the release in October 2008, the names of the releases
119were changed from numerical release numbers without deeper meaning
120into a time stamp based numbering. Regular releases are identified by
121names consisting of the calendar year and month of the release date.
122Additional fields (if present) indicate release candidates or bug fix
123releases in "stable" maintenance trees.
wdenk93f19cc2002-12-17 17:55:09 +0000124
Thomas Weber360d8832010-09-28 08:06:25 +0200125Examples:
Wolfgang Denkc0f40852011-10-26 10:21:21 +0000126 U-Boot v2009.11 - Release November 2009
Thomas Weber360d8832010-09-28 08:06:25 +0200127 U-Boot v2009.11.1 - Release 1 in version November 2009 stable tree
Jelle van der Waa0de21ec2016-10-30 17:30:30 +0100128 U-Boot v2010.09-rc1 - Release candidate 1 for September 2010 release
wdenk93f19cc2002-12-17 17:55:09 +0000129
130
wdenkc6097192002-11-03 00:24:07 +0000131Directory Hierarchy:
132====================
133
Peter Tyser8d321b82010-04-12 22:28:21 -0500134/arch Architecture specific files
Masahiro Yamada6eae68e2014-03-07 18:02:02 +0900135 /arc Files generic to ARC architecture
Peter Tyser8d321b82010-04-12 22:28:21 -0500136 /arm Files generic to ARM architecture
Peter Tyser8d321b82010-04-12 22:28:21 -0500137 /m68k Files generic to m68k architecture
Peter Tyser8d321b82010-04-12 22:28:21 -0500138 /microblaze Files generic to microblaze architecture
Peter Tyser8d321b82010-04-12 22:28:21 -0500139 /mips Files generic to MIPS architecture
Macpaul Linafc1ce82011-10-19 20:41:11 +0000140 /nds32 Files generic to NDS32 architecture
Peter Tyser8d321b82010-04-12 22:28:21 -0500141 /nios2 Files generic to Altera NIOS2 architecture
Robert P. J. Day33c77312013-09-15 18:34:15 -0400142 /openrisc Files generic to OpenRISC architecture
Stefan Roesea47a12b2010-04-15 16:07:28 +0200143 /powerpc Files generic to PowerPC architecture
Rick Chen3fafced2017-12-26 13:55:59 +0800144 /riscv Files generic to RISC-V architecture
Robert P. J. Day7207b362015-12-19 07:16:10 -0500145 /sandbox Files generic to HW-independent "sandbox"
Peter Tyser8d321b82010-04-12 22:28:21 -0500146 /sh Files generic to SH architecture
Robert P. J. Day33c77312013-09-15 18:34:15 -0400147 /x86 Files generic to x86 architecture
Peter Tyser8d321b82010-04-12 22:28:21 -0500148/api Machine/arch independent API for external apps
149/board Board dependent files
Xu Ziyuan740f7e52016-08-26 19:54:49 +0800150/cmd U-Boot commands functions
Peter Tyser8d321b82010-04-12 22:28:21 -0500151/common Misc architecture independent functions
Robert P. J. Day7207b362015-12-19 07:16:10 -0500152/configs Board default configuration files
Peter Tyser8d321b82010-04-12 22:28:21 -0500153/disk Code for disk drive partition handling
154/doc Documentation (don't expect too much)
155/drivers Commonly used device drivers
Robert P. J. Day33c77312013-09-15 18:34:15 -0400156/dts Contains Makefile for building internal U-Boot fdt.
Peter Tyser8d321b82010-04-12 22:28:21 -0500157/examples Example code for standalone applications, etc.
158/fs Filesystem code (cramfs, ext2, jffs2, etc.)
159/include Header Files
Robert P. J. Day7207b362015-12-19 07:16:10 -0500160/lib Library routines generic to all architectures
161/Licenses Various license files
Peter Tyser8d321b82010-04-12 22:28:21 -0500162/net Networking code
163/post Power On Self Test
Robert P. J. Day7207b362015-12-19 07:16:10 -0500164/scripts Various build scripts and Makefiles
165/test Various unit test files
Peter Tyser8d321b82010-04-12 22:28:21 -0500166/tools Tools to build S-Record or U-Boot images, etc.
wdenkc6097192002-11-03 00:24:07 +0000167
wdenkc6097192002-11-03 00:24:07 +0000168Software Configuration:
169=======================
170
171Configuration is usually done using C preprocessor defines; the
172rationale behind that is to avoid dead code whenever possible.
173
174There are two classes of configuration variables:
175
176* Configuration _OPTIONS_:
177 These are selectable by the user and have names beginning with
178 "CONFIG_".
179
180* Configuration _SETTINGS_:
181 These depend on the hardware etc. and should not be meddled with if
182 you don't know what you're doing; they have names beginning with
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +0200183 "CONFIG_SYS_".
wdenkc6097192002-11-03 00:24:07 +0000184
Robert P. J. Day7207b362015-12-19 07:16:10 -0500185Previously, all configuration was done by hand, which involved creating
186symbolic links and editing configuration files manually. More recently,
187U-Boot has added the Kbuild infrastructure used by the Linux kernel,
188allowing you to use the "make menuconfig" command to configure your
189build.
wdenkc6097192002-11-03 00:24:07 +0000190
191
192Selection of Processor Architecture and Board Type:
193---------------------------------------------------
194
195For all supported boards there are ready-to-use default
Holger Freytherab584d62014-08-04 09:26:05 +0200196configurations available; just type "make <board_name>_defconfig".
wdenkc6097192002-11-03 00:24:07 +0000197
198Example: For a TQM823L module type:
199
200 cd u-boot
Holger Freytherab584d62014-08-04 09:26:05 +0200201 make TQM823L_defconfig
wdenkc6097192002-11-03 00:24:07 +0000202
Robert P. J. Day7207b362015-12-19 07:16:10 -0500203Note: If you're looking for the default configuration file for a board
204you're sure used to be there but is now missing, check the file
205doc/README.scrapyard for a list of no longer supported boards.
wdenkc6097192002-11-03 00:24:07 +0000206
Simon Glass75b3c3a2014-03-22 17:12:59 -0600207Sandbox Environment:
208--------------------
209
210U-Boot can be built natively to run on a Linux host using the 'sandbox'
211board. This allows feature development which is not board- or architecture-
212specific to be undertaken on a native platform. The sandbox is also used to
213run some of U-Boot's tests.
214
Jagannadha Sutradharudu Teki6b1978f2014-08-31 21:19:43 +0530215See board/sandbox/README.sandbox for more details.
Simon Glass75b3c3a2014-03-22 17:12:59 -0600216
217
Simon Glassdb910352015-03-03 08:03:00 -0700218Board Initialisation Flow:
219--------------------------
220
221This is the intended start-up flow for boards. This should apply for both
Robert P. J. Day7207b362015-12-19 07:16:10 -0500222SPL and U-Boot proper (i.e. they both follow the same rules).
Simon Glassdb910352015-03-03 08:03:00 -0700223
Robert P. J. Day7207b362015-12-19 07:16:10 -0500224Note: "SPL" stands for "Secondary Program Loader," which is explained in
225more detail later in this file.
226
227At present, SPL mostly uses a separate code path, but the function names
228and roles of each function are the same. Some boards or architectures
229may not conform to this. At least most ARM boards which use
230CONFIG_SPL_FRAMEWORK conform to this.
231
232Execution typically starts with an architecture-specific (and possibly
233CPU-specific) start.S file, such as:
234
235 - arch/arm/cpu/armv7/start.S
236 - arch/powerpc/cpu/mpc83xx/start.S
237 - arch/mips/cpu/start.S
238
239and so on. From there, three functions are called; the purpose and
240limitations of each of these functions are described below.
Simon Glassdb910352015-03-03 08:03:00 -0700241
242lowlevel_init():
243 - purpose: essential init to permit execution to reach board_init_f()
244 - no global_data or BSS
245 - there is no stack (ARMv7 may have one but it will soon be removed)
246 - must not set up SDRAM or use console
247 - must only do the bare minimum to allow execution to continue to
248 board_init_f()
249 - this is almost never needed
250 - return normally from this function
251
252board_init_f():
253 - purpose: set up the machine ready for running board_init_r():
254 i.e. SDRAM and serial UART
255 - global_data is available
256 - stack is in SRAM
257 - BSS is not available, so you cannot use global/static variables,
258 only stack variables and global_data
259
260 Non-SPL-specific notes:
261 - dram_init() is called to set up DRAM. If already done in SPL this
262 can do nothing
263
264 SPL-specific notes:
265 - you can override the entire board_init_f() function with your own
266 version as needed.
267 - preloader_console_init() can be called here in extremis
268 - should set up SDRAM, and anything needed to make the UART work
269 - these is no need to clear BSS, it will be done by crt0.S
270 - must return normally from this function (don't call board_init_r()
271 directly)
272
273Here the BSS is cleared. For SPL, if CONFIG_SPL_STACK_R is defined, then at
274this point the stack and global_data are relocated to below
275CONFIG_SPL_STACK_R_ADDR. For non-SPL, U-Boot is relocated to run at the top of
276memory.
277
278board_init_r():
279 - purpose: main execution, common code
280 - global_data is available
281 - SDRAM is available
282 - BSS is available, all static/global variables can be used
283 - execution eventually continues to main_loop()
284
285 Non-SPL-specific notes:
286 - U-Boot is relocated to the top of memory and is now running from
287 there.
288
289 SPL-specific notes:
290 - stack is optionally in SDRAM, if CONFIG_SPL_STACK_R is defined and
291 CONFIG_SPL_STACK_R_ADDR points into SDRAM
292 - preloader_console_init() can be called here - typically this is
Ley Foon Tan0680f1b2017-05-03 17:13:32 +0800293 done by selecting CONFIG_SPL_BOARD_INIT and then supplying a
Simon Glassdb910352015-03-03 08:03:00 -0700294 spl_board_init() function containing this call
295 - loads U-Boot or (in falcon mode) Linux
296
297
298
wdenkc6097192002-11-03 00:24:07 +0000299Configuration Options:
300----------------------
301
302Configuration depends on the combination of board and CPU type; all
303such information is kept in a configuration file
304"include/configs/<board_name>.h".
305
306Example: For a TQM823L module, all configuration settings are in
307"include/configs/TQM823L.h".
308
309
wdenk7f6c2cb2002-11-10 22:06:23 +0000310Many of the options are named exactly as the corresponding Linux
311kernel configuration options. The intention is to make it easier to
312build a config tool - later.
313
Ashish Kumar63b23162017-08-11 11:09:14 +0530314- ARM Platform Bus Type(CCI):
315 CoreLink Cache Coherent Interconnect (CCI) is ARM BUS which
316 provides full cache coherency between two clusters of multi-core
317 CPUs and I/O coherency for devices and I/O masters
318
319 CONFIG_SYS_FSL_HAS_CCI400
320
321 Defined For SoC that has cache coherent interconnect
322 CCN-400
wdenk7f6c2cb2002-11-10 22:06:23 +0000323
Ashish Kumarc055cee2017-08-18 10:54:36 +0530324 CONFIG_SYS_FSL_HAS_CCN504
325
326 Defined for SoC that has cache coherent interconnect CCN-504
327
wdenkc6097192002-11-03 00:24:07 +0000328The following options need to be configured:
329
Kim Phillips26281142007-08-10 13:28:25 -0500330- CPU Type: Define exactly one, e.g. CONFIG_MPC85XX.
wdenkc6097192002-11-03 00:24:07 +0000331
Kim Phillips26281142007-08-10 13:28:25 -0500332- Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS.
Wolfgang Denk6ccec442006-10-24 14:42:37 +0200333
Kumar Gala66412c62011-02-18 05:40:54 -0600334- 85xx CPU Options:
York Sunffd06e02012-10-08 07:44:30 +0000335 CONFIG_SYS_PPC64
336
337 Specifies that the core is a 64-bit PowerPC implementation (implements
338 the "64" category of the Power ISA). This is necessary for ePAPR
339 compliance, among other possible reasons.
340
Kumar Gala66412c62011-02-18 05:40:54 -0600341 CONFIG_SYS_FSL_TBCLK_DIV
342
343 Defines the core time base clock divider ratio compared to the
344 system clock. On most PQ3 devices this is 8, on newer QorIQ
345 devices it can be 16 or 32. The ratio varies from SoC to Soc.
346
Kumar Gala8f290842011-05-20 00:39:21 -0500347 CONFIG_SYS_FSL_PCIE_COMPAT
348
349 Defines the string to utilize when trying to match PCIe device
350 tree nodes for the given platform.
351
Scott Wood33eee332012-08-14 10:14:53 +0000352 CONFIG_SYS_FSL_ERRATUM_A004510
353
354 Enables a workaround for erratum A004510. If set,
355 then CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV and
356 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY must be set.
357
358 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV
359 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 (optional)
360
361 Defines one or two SoC revisions (low 8 bits of SVR)
362 for which the A004510 workaround should be applied.
363
364 The rest of SVR is either not relevant to the decision
365 of whether the erratum is present (e.g. p2040 versus
366 p2041) or is implied by the build target, which controls
367 whether CONFIG_SYS_FSL_ERRATUM_A004510 is set.
368
369 See Freescale App Note 4493 for more information about
370 this erratum.
371
Prabhakar Kushwaha74fa22e2013-04-16 13:27:44 +0530372 CONFIG_A003399_NOR_WORKAROUND
373 Enables a workaround for IFC erratum A003399. It is only
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -0800374 required during NOR boot.
Prabhakar Kushwaha74fa22e2013-04-16 13:27:44 +0530375
Prabhakar Kushwaha9f074e62014-10-29 22:33:09 +0530376 CONFIG_A008044_WORKAROUND
377 Enables a workaround for T1040/T1042 erratum A008044. It is only
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -0800378 required during NAND boot and valid for Rev 1.0 SoC revision
Prabhakar Kushwaha9f074e62014-10-29 22:33:09 +0530379
Scott Wood33eee332012-08-14 10:14:53 +0000380 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY
381
382 This is the value to write into CCSR offset 0x18600
383 according to the A004510 workaround.
384
Priyanka Jain64501c62013-07-02 09:21:04 +0530385 CONFIG_SYS_FSL_DSP_DDR_ADDR
386 This value denotes start offset of DDR memory which is
387 connected exclusively to the DSP cores.
388
Priyanka Jain765b0bd2013-04-04 09:31:54 +0530389 CONFIG_SYS_FSL_DSP_M2_RAM_ADDR
390 This value denotes start offset of M2 memory
391 which is directly connected to the DSP core.
392
Priyanka Jain64501c62013-07-02 09:21:04 +0530393 CONFIG_SYS_FSL_DSP_M3_RAM_ADDR
394 This value denotes start offset of M3 memory which is directly
395 connected to the DSP core.
396
Priyanka Jain765b0bd2013-04-04 09:31:54 +0530397 CONFIG_SYS_FSL_DSP_CCSRBAR_DEFAULT
398 This value denotes start offset of DSP CCSR space.
399
Priyanka Jainb1359912013-12-17 14:25:52 +0530400 CONFIG_SYS_FSL_SINGLE_SOURCE_CLK
401 Single Source Clock is clocking mode present in some of FSL SoC's.
402 In this mode, a single differential clock is used to supply
403 clocks to the sysclock, ddrclock and usbclock.
404
Aneesh Bansalfb4a2402014-03-18 23:40:26 +0530405 CONFIG_SYS_CPC_REINIT_F
406 This CONFIG is defined when the CPC is configured as SRAM at the
Bin Menga1875592016-02-05 19:30:11 -0800407 time of U-Boot entry and is required to be re-initialized.
Aneesh Bansalfb4a2402014-03-18 23:40:26 +0530408
Tang Yuantianaade2002014-04-17 15:33:46 +0800409 CONFIG_DEEP_SLEEP
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -0800410 Indicates this SoC supports deep sleep feature. If deep sleep is
Tang Yuantianaade2002014-04-17 15:33:46 +0800411 supported, core will start to execute uboot when wakes up.
412
Daniel Schwierzeck6cb461b2012-04-02 02:57:56 +0000413- Generic CPU options:
414 CONFIG_SYS_BIG_ENDIAN, CONFIG_SYS_LITTLE_ENDIAN
415
416 Defines the endianess of the CPU. Implementation of those
417 values is arch specific.
418
York Sun5614e712013-09-30 09:22:09 -0700419 CONFIG_SYS_FSL_DDR
420 Freescale DDR driver in use. This type of DDR controller is
421 found in mpc83xx, mpc85xx, mpc86xx as well as some ARM core
422 SoCs.
423
424 CONFIG_SYS_FSL_DDR_ADDR
425 Freescale DDR memory-mapped register base.
426
427 CONFIG_SYS_FSL_DDR_EMU
428 Specify emulator support for DDR. Some DDR features such as
429 deskew training are not available.
430
431 CONFIG_SYS_FSL_DDRC_GEN1
432 Freescale DDR1 controller.
433
434 CONFIG_SYS_FSL_DDRC_GEN2
435 Freescale DDR2 controller.
436
437 CONFIG_SYS_FSL_DDRC_GEN3
438 Freescale DDR3 controller.
439
York Sun34e026f2014-03-27 17:54:47 -0700440 CONFIG_SYS_FSL_DDRC_GEN4
441 Freescale DDR4 controller.
442
York Sun9ac4ffb2013-09-30 14:20:51 -0700443 CONFIG_SYS_FSL_DDRC_ARM_GEN3
444 Freescale DDR3 controller for ARM-based SoCs.
445
York Sun5614e712013-09-30 09:22:09 -0700446 CONFIG_SYS_FSL_DDR1
447 Board config to use DDR1. It can be enabled for SoCs with
448 Freescale DDR1 or DDR2 controllers, depending on the board
449 implemetation.
450
451 CONFIG_SYS_FSL_DDR2
Robert P. J. Day62a3b7d2016-07-15 13:44:45 -0400452 Board config to use DDR2. It can be enabled for SoCs with
York Sun5614e712013-09-30 09:22:09 -0700453 Freescale DDR2 or DDR3 controllers, depending on the board
454 implementation.
455
456 CONFIG_SYS_FSL_DDR3
457 Board config to use DDR3. It can be enabled for SoCs with
York Sun34e026f2014-03-27 17:54:47 -0700458 Freescale DDR3 or DDR3L controllers.
459
460 CONFIG_SYS_FSL_DDR3L
461 Board config to use DDR3L. It can be enabled for SoCs with
462 DDR3L controllers.
463
464 CONFIG_SYS_FSL_DDR4
465 Board config to use DDR4. It can be enabled for SoCs with
466 DDR4 controllers.
York Sun5614e712013-09-30 09:22:09 -0700467
Prabhakar Kushwaha1b4175d2014-01-18 12:28:30 +0530468 CONFIG_SYS_FSL_IFC_BE
469 Defines the IFC controller register space as Big Endian
470
471 CONFIG_SYS_FSL_IFC_LE
472 Defines the IFC controller register space as Little Endian
473
Prabhakar Kushwaha1c407072017-02-02 15:01:26 +0530474 CONFIG_SYS_FSL_IFC_CLK_DIV
475 Defines divider of platform clock(clock input to IFC controller).
476
Prabhakar Kushwahaadd63f92017-02-02 15:02:00 +0530477 CONFIG_SYS_FSL_LBC_CLK_DIV
478 Defines divider of platform clock(clock input to eLBC controller).
479
Prabhakar Kushwaha690e4252014-01-13 11:28:04 +0530480 CONFIG_SYS_FSL_PBL_PBI
481 It enables addition of RCW (Power on reset configuration) in built image.
482 Please refer doc/README.pblimage for more details
483
484 CONFIG_SYS_FSL_PBL_RCW
485 It adds PBI(pre-boot instructions) commands in u-boot build image.
486 PBI commands can be used to configure SoC before it starts the execution.
487 Please refer doc/README.pblimage for more details
488
Prabhakar Kushwaha89ad7be2014-04-08 19:13:34 +0530489 CONFIG_SPL_FSL_PBL
490 It adds a target to create boot binary having SPL binary in PBI format
491 concatenated with u-boot binary.
492
York Sun4e5b1bd2014-02-10 13:59:42 -0800493 CONFIG_SYS_FSL_DDR_BE
494 Defines the DDR controller register space as Big Endian
495
496 CONFIG_SYS_FSL_DDR_LE
497 Defines the DDR controller register space as Little Endian
498
York Sun6b9e3092014-02-10 13:59:43 -0800499 CONFIG_SYS_FSL_DDR_SDRAM_BASE_PHY
500 Physical address from the view of DDR controllers. It is the
501 same as CONFIG_SYS_DDR_SDRAM_BASE for all Power SoCs. But
502 it could be different for ARM SoCs.
503
York Sun6b1e1252014-02-10 13:59:44 -0800504 CONFIG_SYS_FSL_DDR_INTLV_256B
505 DDR controller interleaving on 256-byte. This is a special
506 interleaving mode, handled by Dickens for Freescale layerscape
507 SoCs with ARM core.
508
York Sun1d71efb2014-08-01 15:51:00 -0700509 CONFIG_SYS_FSL_DDR_MAIN_NUM_CTRLS
510 Number of controllers used as main memory.
511
512 CONFIG_SYS_FSL_OTHER_DDR_NUM_CTRLS
513 Number of controllers used for other than main memory.
514
Prabhakar Kushwaha44937212015-11-09 16:42:07 +0530515 CONFIG_SYS_FSL_HAS_DP_DDR
516 Defines the SoC has DP-DDR used for DPAA.
517
Ruchika Gupta028dbb82014-09-09 11:50:31 +0530518 CONFIG_SYS_FSL_SEC_BE
519 Defines the SEC controller register space as Big Endian
520
521 CONFIG_SYS_FSL_SEC_LE
522 Defines the SEC controller register space as Little Endian
523
Daniel Schwierzeck92bbd642011-07-27 13:22:39 +0200524- MIPS CPU options:
525 CONFIG_SYS_INIT_SP_OFFSET
526
527 Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack
528 pointer. This is needed for the temporary stack before
529 relocation.
530
531 CONFIG_SYS_MIPS_CACHE_MODE
532
533 Cache operation mode for the MIPS CPU.
534 See also arch/mips/include/asm/mipsregs.h.
535 Possible values are:
536 CONF_CM_CACHABLE_NO_WA
537 CONF_CM_CACHABLE_WA
538 CONF_CM_UNCACHED
539 CONF_CM_CACHABLE_NONCOHERENT
540 CONF_CM_CACHABLE_CE
541 CONF_CM_CACHABLE_COW
542 CONF_CM_CACHABLE_CUW
543 CONF_CM_CACHABLE_ACCELERATED
544
545 CONFIG_SYS_XWAY_EBU_BOOTCFG
546
547 Special option for Lantiq XWAY SoCs for booting from NOR flash.
548 See also arch/mips/cpu/mips32/start.S.
549
550 CONFIG_XWAY_SWAP_BYTES
551
552 Enable compilation of tools/xway-swap-bytes needed for Lantiq
553 XWAY SoCs for booting from NOR flash. The U-Boot image needs to
554 be swapped if a flash programmer is used.
555
Christian Rieschb67d8812012-02-02 00:44:39 +0000556- ARM options:
557 CONFIG_SYS_EXCEPTION_VECTORS_HIGH
558
559 Select high exception vectors of the ARM core, e.g., do not
560 clear the V bit of the c1 register of CP15.
561
York Sun207774b2015-03-20 19:28:08 -0700562 COUNTER_FREQUENCY
563 Generic timer clock source frequency.
564
565 COUNTER_FREQUENCY_REAL
566 Generic timer clock source frequency if the real clock is
567 different from COUNTER_FREQUENCY, and can only be determined
568 at run time.
569
Stephen Warren73c38932015-01-19 16:25:52 -0700570- Tegra SoC options:
571 CONFIG_TEGRA_SUPPORT_NON_SECURE
572
573 Support executing U-Boot in non-secure (NS) mode. Certain
574 impossible actions will be skipped if the CPU is in NS mode,
575 such as ARM architectural timer initialization.
576
wdenk5da627a2003-10-09 20:09:04 +0000577- Linux Kernel Interface:
wdenkc6097192002-11-03 00:24:07 +0000578 CONFIG_CLOCKS_IN_MHZ
579
580 U-Boot stores all clock information in Hz
581 internally. For binary compatibility with older Linux
582 kernels (which expect the clocks passed in the
583 bd_info data to be in MHz) the environment variable
584 "clocks_in_mhz" can be defined so that U-Boot
585 converts clock data to MHZ before passing it to the
586 Linux kernel.
wdenkc6097192002-11-03 00:24:07 +0000587 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
Wolfgang Denk218ca722008-03-26 10:40:12 +0100588 "clocks_in_mhz=1" is automatically included in the
wdenkc6097192002-11-03 00:24:07 +0000589 default environment.
590
wdenk5da627a2003-10-09 20:09:04 +0000591 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
592
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -0800593 When transferring memsize parameter to Linux, some versions
wdenk5da627a2003-10-09 20:09:04 +0000594 expect it to be in bytes, others in MB.
595 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
596
Gerald Van Barenfec6d9e2008-06-03 20:34:45 -0400597 CONFIG_OF_LIBFDT
Wolfgang Denkf57f70a2005-10-13 01:45:54 +0200598
599 New kernel versions are expecting firmware settings to be
Gerald Van Baren213bf8c2007-03-31 12:23:51 -0400600 passed using flattened device trees (based on open firmware
601 concepts).
602
603 CONFIG_OF_LIBFDT
604 * New libfdt-based support
605 * Adds the "fdt" command
Kim Phillips3bb342f2007-08-10 14:34:14 -0500606 * The bootm command automatically updates the fdt
Gerald Van Baren213bf8c2007-03-31 12:23:51 -0400607
Wolfgang Denkf57f70a2005-10-13 01:45:54 +0200608 OF_TBCLK - The timebase frequency.
Kumar Galac2871f02006-01-11 13:59:02 -0600609 OF_STDOUT_PATH - The path to the console device
Wolfgang Denkf57f70a2005-10-13 01:45:54 +0200610
Marcel Ziswiler11ccc332008-07-09 08:17:15 +0200611 boards with QUICC Engines require OF_QE to set UCC MAC
612 addresses
Kim Phillips3bb342f2007-08-10 14:34:14 -0500613
Kumar Gala4e253132006-01-11 13:54:17 -0600614 CONFIG_OF_BOARD_SETUP
615
616 Board code has addition modification that it wants to make
617 to the flat device tree before handing it off to the kernel
wdenk6705d812004-08-02 23:22:59 +0000618
Simon Glassc654b512014-10-23 18:58:54 -0600619 CONFIG_OF_SYSTEM_SETUP
620
621 Other code has addition modification that it wants to make
622 to the flat device tree before handing it off to the kernel.
623 This causes ft_system_setup() to be called before booting
624 the kernel.
625
Heiko Schocher3887c3f2009-09-23 07:56:08 +0200626 CONFIG_OF_IDE_FIXUP
627
628 U-Boot can detect if an IDE device is present or not.
629 If not, and this new config option is activated, U-Boot
630 removes the ATA node from the DTS before booting Linux,
631 so the Linux IDE driver does not probe the device and
632 crash. This is needed for buggy hardware (uc101) where
633 no pull down resistor is connected to the signal IDE5V_DD7.
634
Igor Grinberg7eb29392011-07-14 05:45:07 +0000635 CONFIG_MACH_TYPE [relevant for ARM only][mandatory]
636
637 This setting is mandatory for all boards that have only one
638 machine type and must be used to specify the machine type
639 number as it appears in the ARM machine registry
640 (see http://www.arm.linux.org.uk/developer/machines/).
641 Only boards that have multiple machine types supported
642 in a single configuration file and the machine type is
643 runtime discoverable, do not have to use this setting.
644
Niklaus Giger0b2f4ec2008-11-03 22:13:47 +0100645- vxWorks boot parameters:
646
647 bootvx constructs a valid bootline using the following
Bin Meng9e98b7e2015-10-07 20:19:17 -0700648 environments variables: bootdev, bootfile, ipaddr, netmask,
649 serverip, gatewayip, hostname, othbootargs.
Niklaus Giger0b2f4ec2008-11-03 22:13:47 +0100650 It loads the vxWorks image pointed bootfile.
651
Niklaus Giger0b2f4ec2008-11-03 22:13:47 +0100652 Note: If a "bootargs" environment is defined, it will overwride
653 the defaults discussed just above.
654
Aneesh V2c451f72011-06-16 23:30:47 +0000655- Cache Configuration:
656 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot
657 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot
658 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot
659
Aneesh V93bc2192011-06-16 23:30:51 +0000660- Cache Configuration for ARM:
661 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache
662 controller
663 CONFIG_SYS_PL310_BASE - Physical base address of PL310
664 controller register space
665
wdenk6705d812004-08-02 23:22:59 +0000666- Serial Ports:
Andreas Engel48d01922008-09-08 14:30:53 +0200667 CONFIG_PL010_SERIAL
wdenk6705d812004-08-02 23:22:59 +0000668
669 Define this if you want support for Amba PrimeCell PL010 UARTs.
670
Andreas Engel48d01922008-09-08 14:30:53 +0200671 CONFIG_PL011_SERIAL
wdenk6705d812004-08-02 23:22:59 +0000672
673 Define this if you want support for Amba PrimeCell PL011 UARTs.
674
675 CONFIG_PL011_CLOCK
676
677 If you have Amba PrimeCell PL011 UARTs, set this variable to
678 the clock speed of the UARTs.
679
680 CONFIG_PL01x_PORTS
681
682 If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
683 define this to a list of base addresses for each (supported)
684 port. See e.g. include/configs/versatile.h
685
Karicheri, Muralidharand57dee52014-04-09 15:38:46 -0400686 CONFIG_SERIAL_HW_FLOW_CONTROL
687
688 Define this variable to enable hw flow control in serial driver.
689 Current user of this option is drivers/serial/nsl16550.c driver
wdenk6705d812004-08-02 23:22:59 +0000690
wdenkc6097192002-11-03 00:24:07 +0000691- Console Baudrate:
692 CONFIG_BAUDRATE - in bps
693 Select one of the baudrates listed in
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +0200694 CONFIG_SYS_BAUDRATE_TABLE, see below.
wdenkc6097192002-11-03 00:24:07 +0000695
wdenkc6097192002-11-03 00:24:07 +0000696- Autoboot Command:
697 CONFIG_BOOTCOMMAND
698 Only needed when CONFIG_BOOTDELAY is enabled;
699 define a command string that is automatically executed
700 when no character is read on the console interface
701 within "Boot Delay" after reset.
702
wdenkc6097192002-11-03 00:24:07 +0000703 CONFIG_RAMBOOT and CONFIG_NFSBOOT
wdenk43d96162003-03-06 00:02:04 +0000704 The value of these goes into the environment as
705 "ramboot" and "nfsboot" respectively, and can be used
706 as a convenience, when switching between booting from
Marcel Ziswiler11ccc332008-07-09 08:17:15 +0200707 RAM and NFS.
wdenkc6097192002-11-03 00:24:07 +0000708
709- Pre-Boot Commands:
710 CONFIG_PREBOOT
711
712 When this option is #defined, the existence of the
713 environment variable "preboot" will be checked
714 immediately before starting the CONFIG_BOOTDELAY
715 countdown and/or running the auto-boot command resp.
716 entering interactive mode.
717
718 This feature is especially useful when "preboot" is
719 automatically generated or modified. For an example
720 see the LWMON board specific code: here "preboot" is
721 modified when the user holds down a certain
722 combination of keys on the (special) keyboard when
723 booting the systems
724
725- Serial Download Echo Mode:
726 CONFIG_LOADS_ECHO
727 If defined to 1, all characters received during a
728 serial download (using the "loads" command) are
729 echoed back. This might be needed by some terminal
730 emulations (like "cu"), but may as well just take
731 time on others. This setting #define's the initial
732 value of the "loads_echo" environment variable.
733
Jon Loeliger602ad3b2007-06-11 19:03:39 -0500734- Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined)
wdenkc6097192002-11-03 00:24:07 +0000735 CONFIG_KGDB_BAUDRATE
736 Select one of the baudrates listed in
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +0200737 CONFIG_SYS_BAUDRATE_TABLE, see below.
wdenkc6097192002-11-03 00:24:07 +0000738
Simon Glass302a6482016-03-13 19:07:28 -0600739- Removal of commands
740 If no commands are needed to boot, you can disable
741 CONFIG_CMDLINE to remove them. In this case, the command line
742 will not be available, and when U-Boot wants to execute the
743 boot command (on start-up) it will call board_run_command()
744 instead. This can reduce image size significantly for very
745 simple boot procedures.
746
Wolfgang Denka5ecbe62013-03-23 23:50:31 +0000747- Regular expression support:
748 CONFIG_REGEX
Wolfgang Denk93e14592013-10-04 17:43:24 +0200749 If this variable is defined, U-Boot is linked against
750 the SLRE (Super Light Regular Expression) library,
751 which adds regex support to some commands, as for
752 example "env grep" and "setexpr".
Wolfgang Denka5ecbe62013-03-23 23:50:31 +0000753
Simon Glass45ba8072011-10-15 05:48:20 +0000754- Device tree:
755 CONFIG_OF_CONTROL
756 If this variable is defined, U-Boot will use a device tree
757 to configure its devices, instead of relying on statically
758 compiled #defines in the board file. This option is
759 experimental and only available on a few boards. The device
760 tree is available in the global data as gd->fdt_blob.
761
Simon Glass2c0f79e2011-10-24 19:15:31 +0000762 U-Boot needs to get its device tree from somewhere. This can
Alex Deymo82f766d2017-04-02 01:25:20 -0700763 be done using one of the three options below:
Simon Glassbbb0b122011-10-15 05:48:21 +0000764
765 CONFIG_OF_EMBED
766 If this variable is defined, U-Boot will embed a device tree
767 binary in its image. This device tree file should be in the
768 board directory and called <soc>-<board>.dts. The binary file
769 is then picked up in board_init_f() and made available through
Nobuhiro Iwamatsueb3eb602017-08-26 07:34:14 +0900770 the global data structure as gd->fdt_blob.
Simon Glass45ba8072011-10-15 05:48:20 +0000771
Simon Glass2c0f79e2011-10-24 19:15:31 +0000772 CONFIG_OF_SEPARATE
773 If this variable is defined, U-Boot will build a device tree
774 binary. It will be called u-boot.dtb. Architecture-specific
775 code will locate it at run-time. Generally this works by:
776
777 cat u-boot.bin u-boot.dtb >image.bin
778
779 and in fact, U-Boot does this for you, creating a file called
780 u-boot-dtb.bin which is useful in the common case. You can
781 still use the individual files if you need something more
782 exotic.
783
Alex Deymo82f766d2017-04-02 01:25:20 -0700784 CONFIG_OF_BOARD
785 If this variable is defined, U-Boot will use the device tree
786 provided by the board at runtime instead of embedding one with
787 the image. Only boards defining board_fdt_blob_setup() support
788 this option (see include/fdtdec.h file).
789
wdenkc6097192002-11-03 00:24:07 +0000790- Watchdog:
791 CONFIG_WATCHDOG
792 If this variable is defined, it enables watchdog
Detlev Zundel6abe6fb2011-04-27 05:25:59 +0000793 support for the SoC. There must be support in the SoC
Christophe Leroy907208c2017-07-06 10:23:22 +0200794 specific code for a watchdog. For the 8xx
795 CPUs, the SIU Watchdog feature is enabled in the SYPCR
796 register. When supported for a specific SoC is
797 available, then no further board specific code should
798 be needed to use it.
Detlev Zundel6abe6fb2011-04-27 05:25:59 +0000799
800 CONFIG_HW_WATCHDOG
801 When using a watchdog circuitry external to the used
802 SoC, then define this variable and provide board
803 specific code for the "hw_watchdog_reset" function.
wdenkc6097192002-11-03 00:24:07 +0000804
Heiko Schocher7bae0d62015-01-21 08:38:22 +0100805 CONFIG_AT91_HW_WDT_TIMEOUT
806 specify the timeout in seconds. default 2 seconds.
807
wdenkc6097192002-11-03 00:24:07 +0000808- Real-Time Clock:
809
Jon Loeliger602ad3b2007-06-11 19:03:39 -0500810 When CONFIG_CMD_DATE is selected, the type of the RTC
wdenkc6097192002-11-03 00:24:07 +0000811 has to be selected, too. Define exactly one of the
812 following options:
813
wdenkc6097192002-11-03 00:24:07 +0000814 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
Fabio Estevam4e8b7542011-10-24 06:44:15 +0000815 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC
wdenkc6097192002-11-03 00:24:07 +0000816 CONFIG_RTC_MC146818 - use MC146818 RTC
wdenk1cb8e982003-03-06 21:55:29 +0000817 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
wdenkc6097192002-11-03 00:24:07 +0000818 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
wdenk7f70e852003-05-20 14:25:27 +0000819 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
Markus Niebel412921d2014-07-21 11:06:16 +0200820 CONFIG_RTC_DS1339 - use Maxim, Inc. DS1339 RTC
wdenk3bac3512003-03-12 10:41:04 +0000821 CONFIG_RTC_DS164x - use Dallas DS164x RTC
Tor Krill9536dfc2008-03-15 15:40:26 +0100822 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC
wdenk4c0d4c32004-06-09 17:34:58 +0000823 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
Chris Packham2bd3cab2017-05-30 12:03:33 +1200824 CONFIG_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337
Heiko Schocher71d19f32011-03-28 09:24:22 +0200825 CONFIG_SYS_RV3029_TCR - enable trickle charger on
826 RV3029 RTC.
wdenkc6097192002-11-03 00:24:07 +0000827
wdenkb37c7e52003-06-30 16:24:52 +0000828 Note that if the RTC uses I2C, then the I2C interface
829 must also be configured. See I2C Support, below.
830
Peter Tysere92739d2008-12-17 16:36:21 -0600831- GPIO Support:
832 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO
Peter Tysere92739d2008-12-17 16:36:21 -0600833
Chris Packham5dec49c2010-12-19 10:12:13 +0000834 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of
835 chip-ngpio pairs that tell the PCA953X driver the number of
836 pins supported by a particular chip.
837
Peter Tysere92739d2008-12-17 16:36:21 -0600838 Note that if the GPIO device uses I2C, then the I2C interface
839 must also be configured. See I2C Support, below.
840
Simon Glassaa532332014-06-11 23:29:41 -0600841- I/O tracing:
842 When CONFIG_IO_TRACE is selected, U-Boot intercepts all I/O
843 accesses and can checksum them or write a list of them out
844 to memory. See the 'iotrace' command for details. This is
845 useful for testing device drivers since it can confirm that
846 the driver behaves the same way before and after a code
847 change. Currently this is supported on sandbox and arm. To
848 add support for your architecture, add '#include <iotrace.h>'
849 to the bottom of arch/<arch>/include/asm/io.h and test.
850
851 Example output from the 'iotrace stats' command is below.
852 Note that if the trace buffer is exhausted, the checksum will
853 still continue to operate.
854
855 iotrace is enabled
856 Start: 10000000 (buffer start address)
857 Size: 00010000 (buffer size)
858 Offset: 00000120 (current buffer offset)
859 Output: 10000120 (start + offset)
860 Count: 00000018 (number of trace records)
861 CRC32: 9526fb66 (CRC32 of all trace records)
862
wdenkc6097192002-11-03 00:24:07 +0000863- Timestamp Support:
864
wdenk43d96162003-03-06 00:02:04 +0000865 When CONFIG_TIMESTAMP is selected, the timestamp
866 (date and time) of an image is printed by image
867 commands like bootm or iminfo. This option is
Jon Loeliger602ad3b2007-06-11 19:03:39 -0500868 automatically enabled when you select CONFIG_CMD_DATE .
wdenkc6097192002-11-03 00:24:07 +0000869
Karl O. Pinc923c46f2012-08-16 06:20:15 +0000870- Partition Labels (disklabels) Supported:
871 Zero or more of the following:
872 CONFIG_MAC_PARTITION Apple's MacOS partition table.
Karl O. Pinc923c46f2012-08-16 06:20:15 +0000873 CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc.
874 CONFIG_EFI_PARTITION GPT partition table, common when EFI is the
875 bootloader. Note 2TB partition limit; see
876 disk/part_efi.c
Simon Glassc649e3c2016-05-01 11:36:02 -0600877 CONFIG_SCSI) you must configure support for at
Karl O. Pinc923c46f2012-08-16 06:20:15 +0000878 least one non-MTD partition type as well.
wdenkc6097192002-11-03 00:24:07 +0000879
880- IDE Reset method:
wdenk4d13cba2004-03-14 14:09:05 +0000881 CONFIG_IDE_RESET_ROUTINE - this is defined in several
882 board configurations files but used nowhere!
wdenkc6097192002-11-03 00:24:07 +0000883
wdenk4d13cba2004-03-14 14:09:05 +0000884 CONFIG_IDE_RESET - is this is defined, IDE Reset will
885 be performed by calling the function
886 ide_set_reset(int reset)
887 which has to be defined in a board specific file
wdenkc6097192002-11-03 00:24:07 +0000888
889- ATAPI Support:
890 CONFIG_ATAPI
891
892 Set this to enable ATAPI support.
893
wdenkc40b2952004-03-13 23:29:43 +0000894- LBA48 Support
895 CONFIG_LBA48
896
897 Set this to enable support for disks larger than 137GB
Heiko Schocher4b142fe2009-12-03 11:21:21 +0100898 Also look at CONFIG_SYS_64BIT_LBA.
wdenkc40b2952004-03-13 23:29:43 +0000899 Whithout these , LBA48 support uses 32bit variables and will 'only'
900 support disks up to 2.1TB.
901
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +0200902 CONFIG_SYS_64BIT_LBA:
wdenkc40b2952004-03-13 23:29:43 +0000903 When enabled, makes the IDE subsystem use 64bit sector addresses.
904 Default is 32bit.
905
wdenkc6097192002-11-03 00:24:07 +0000906- SCSI Support:
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +0200907 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and
908 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID *
909 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the
wdenkc6097192002-11-03 00:24:07 +0000910 maximum numbers of LUNs, SCSI ID's and target
911 devices.
wdenkc6097192002-11-03 00:24:07 +0000912
Wolfgang Denk93e14592013-10-04 17:43:24 +0200913 The environment variable 'scsidevs' is set to the number of
914 SCSI devices found during the last scan.
Stefan Reinauer447c0312012-10-29 05:23:48 +0000915
wdenkc6097192002-11-03 00:24:07 +0000916- NETWORK Support (PCI):
wdenk682011f2003-06-03 23:54:09 +0000917 CONFIG_E1000
Kyle Moffettce5207e2011-10-18 11:05:29 +0000918 Support for Intel 8254x/8257x gigabit chips.
919
920 CONFIG_E1000_SPI
921 Utility code for direct access to the SPI bus on Intel 8257x.
922 This does not do anything useful unless you set at least one
923 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC.
924
925 CONFIG_E1000_SPI_GENERIC
926 Allow generic access to the SPI bus on the Intel 8257x, for
927 example with the "sspi" command.
928
wdenkc6097192002-11-03 00:24:07 +0000929 CONFIG_EEPRO100
930 Support for Intel 82557/82559/82559ER chips.
Marcel Ziswiler11ccc332008-07-09 08:17:15 +0200931 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM
wdenkc6097192002-11-03 00:24:07 +0000932 write routine for first time initialisation.
933
934 CONFIG_TULIP
935 Support for Digital 2114x chips.
936 Optional CONFIG_TULIP_SELECT_MEDIA for board specific
937 modem chip initialisation (KS8761/QS6611).
938
939 CONFIG_NATSEMI
940 Support for National dp83815 chips.
941
942 CONFIG_NS8382X
943 Support for National dp8382[01] gigabit chips.
944
wdenk45219c42003-05-12 21:50:16 +0000945- NETWORK Support (other):
946
Jens Scharsigc041e9d2010-01-23 12:03:45 +0100947 CONFIG_DRIVER_AT91EMAC
948 Support for AT91RM9200 EMAC.
949
950 CONFIG_RMII
951 Define this to use reduced MII inteface
952
953 CONFIG_DRIVER_AT91EMAC_QUIET
954 If this defined, the driver is quiet.
955 The driver doen't show link status messages.
956
Rob Herringefdd7312011-12-15 11:15:49 +0000957 CONFIG_CALXEDA_XGMAC
958 Support for the Calxeda XGMAC device
959
Ashok3bb46d22012-10-15 06:20:47 +0000960 CONFIG_LAN91C96
wdenk45219c42003-05-12 21:50:16 +0000961 Support for SMSC's LAN91C96 chips.
962
wdenk45219c42003-05-12 21:50:16 +0000963 CONFIG_LAN91C96_USE_32_BIT
964 Define this to enable 32 bit addressing
965
Ashok3bb46d22012-10-15 06:20:47 +0000966 CONFIG_SMC91111
wdenkf39748a2004-06-09 13:37:52 +0000967 Support for SMSC's LAN91C111 chip
968
969 CONFIG_SMC91111_BASE
970 Define this to hold the physical address
971 of the device (I/O space)
972
973 CONFIG_SMC_USE_32_BIT
974 Define this if data bus is 32 bits
975
976 CONFIG_SMC_USE_IOFUNCS
977 Define this to use i/o functions instead of macros
978 (some hardware wont work with macros)
979
Heiko Schocherdc02bad2011-11-15 10:00:04 -0500980 CONFIG_DRIVER_TI_EMAC
981 Support for davinci emac
982
983 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT
984 Define this if you have more then 3 PHYs.
985
Macpaul Linb3dbf4a52010-12-21 16:59:46 +0800986 CONFIG_FTGMAC100
987 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet
988
989 CONFIG_FTGMAC100_EGIGA
990 Define this to use GE link update with gigabit PHY.
991 Define this if FTGMAC100 is connected to gigabit PHY.
992 If your system has 10/100 PHY only, it might not occur
993 wrong behavior. Because PHY usually return timeout or
994 useless data when polling gigabit status and gigabit
995 control registers. This behavior won't affect the
996 correctnessof 10/100 link speed update.
997
Yoshihiro Shimoda3d0075f2011-01-27 10:06:03 +0900998 CONFIG_SH_ETHER
999 Support for Renesas on-chip Ethernet controller
1000
1001 CONFIG_SH_ETHER_USE_PORT
1002 Define the number of ports to be used
1003
1004 CONFIG_SH_ETHER_PHY_ADDR
1005 Define the ETH PHY's address
1006
Yoshihiro Shimoda68260aa2011-01-27 10:06:08 +09001007 CONFIG_SH_ETHER_CACHE_WRITEBACK
1008 If this option is set, the driver enables cache flush.
1009
Heiko Schocherb2f97cf2014-07-18 06:07:19 +02001010- PWM Support:
1011 CONFIG_PWM_IMX
Robert P. J. Day5052e812016-09-13 08:35:18 -04001012 Support for PWM module on the imx6.
Heiko Schocherb2f97cf2014-07-18 06:07:19 +02001013
Vadim Bendebury5e124722011-10-17 08:36:14 +00001014- TPM Support:
Che-liang Chiou90899cc2013-04-12 11:04:34 +00001015 CONFIG_TPM
1016 Support TPM devices.
1017
Christophe Ricard0766ad22015-10-06 22:54:41 +02001018 CONFIG_TPM_TIS_INFINEON
1019 Support for Infineon i2c bus TPM devices. Only one device
Tom Wai-Hong Tam1b393db2013-04-12 11:04:37 +00001020 per system is supported at this time.
1021
Tom Wai-Hong Tam1b393db2013-04-12 11:04:37 +00001022 CONFIG_TPM_TIS_I2C_BURST_LIMITATION
1023 Define the burst count bytes upper limit
1024
Christophe Ricard3aa74082016-01-21 23:27:13 +01001025 CONFIG_TPM_ST33ZP24
1026 Support for STMicroelectronics TPM devices. Requires DM_TPM support.
1027
1028 CONFIG_TPM_ST33ZP24_I2C
1029 Support for STMicroelectronics ST33ZP24 I2C devices.
1030 Requires TPM_ST33ZP24 and I2C.
1031
Christophe Ricardb75fdc12016-01-21 23:27:14 +01001032 CONFIG_TPM_ST33ZP24_SPI
1033 Support for STMicroelectronics ST33ZP24 SPI devices.
1034 Requires TPM_ST33ZP24 and SPI.
1035
Dirk Eibachc01939c2013-06-26 15:55:15 +02001036 CONFIG_TPM_ATMEL_TWI
1037 Support for Atmel TWI TPM device. Requires I2C support.
1038
Che-liang Chiou90899cc2013-04-12 11:04:34 +00001039 CONFIG_TPM_TIS_LPC
Vadim Bendebury5e124722011-10-17 08:36:14 +00001040 Support for generic parallel port TPM devices. Only one device
1041 per system is supported at this time.
1042
1043 CONFIG_TPM_TIS_BASE_ADDRESS
1044 Base address where the generic TPM device is mapped
1045 to. Contemporary x86 systems usually map it at
1046 0xfed40000.
1047
Reinhard Pfaube6c1522013-06-26 15:55:13 +02001048 CONFIG_TPM
1049 Define this to enable the TPM support library which provides
1050 functional interfaces to some TPM commands.
1051 Requires support for a TPM device.
1052
1053 CONFIG_TPM_AUTH_SESSIONS
1054 Define this to enable authorized functions in the TPM library.
1055 Requires CONFIG_TPM and CONFIG_SHA1.
1056
wdenkc6097192002-11-03 00:24:07 +00001057- USB Support:
1058 At the moment only the UHCI host controller is
Heiko Schocher064b55c2017-06-14 05:49:40 +02001059 supported (PIP405, MIP405); define
wdenkc6097192002-11-03 00:24:07 +00001060 CONFIG_USB_UHCI to enable it.
1061 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
wdenk30d56fa2004-10-09 22:44:59 +00001062 and define CONFIG_USB_STORAGE to enable the USB
wdenkc6097192002-11-03 00:24:07 +00001063 storage devices.
1064 Note:
1065 Supported are USB Keyboards and USB Floppy drives
1066 (TEAC FD-05PUB).
wdenk4d13cba2004-03-14 14:09:05 +00001067
Simon Glass9ab4ce22012-02-27 10:52:47 +00001068 CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the
1069 txfilltuning field in the EHCI controller on reset.
1070
Oleksandr Tymoshenko6e9e0622014-02-01 21:51:25 -07001071 CONFIG_USB_DWC2_REG_ADDR the physical CPU address of the DWC2
1072 HW module registers.
1073
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +02001074- USB Device:
1075 Define the below if you wish to use the USB console.
1076 Once firmware is rebuilt from a serial console issue the
1077 command "setenv stdin usbtty; setenv stdout usbtty" and
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001078 attach your USB cable. The Unix command "dmesg" should print
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +02001079 it has found a new device. The environment variable usbtty
1080 can be set to gserial or cdc_acm to enable your device to
Wolfgang Denk386eda02006-06-14 18:14:56 +02001081 appear to a USB host as a Linux gserial device or a
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +02001082 Common Device Class Abstract Control Model serial device.
1083 If you select usbtty = gserial you should be able to enumerate
1084 a Linux host by
1085 # modprobe usbserial vendor=0xVendorID product=0xProductID
1086 else if using cdc_acm, simply setting the environment
1087 variable usbtty to be cdc_acm should suffice. The following
1088 might be defined in YourBoardName.h
Wolfgang Denk386eda02006-06-14 18:14:56 +02001089
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +02001090 CONFIG_USB_DEVICE
1091 Define this to build a UDC device
wdenkc6097192002-11-03 00:24:07 +00001092
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +02001093 CONFIG_USB_TTY
1094 Define this to have a tty type of device available to
1095 talk to the UDC device
Wolfgang Denk386eda02006-06-14 18:14:56 +02001096
Vipin KUMARf9da0f82012-03-26 15:38:06 +05301097 CONFIG_USBD_HS
1098 Define this to enable the high speed support for usb
1099 device and usbtty. If this feature is enabled, a routine
1100 int is_usbd_high_speed(void)
1101 also needs to be defined by the driver to dynamically poll
1102 whether the enumeration has succeded at high speed or full
1103 speed.
1104
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001105 CONFIG_SYS_CONSOLE_IS_IN_ENV
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +02001106 Define this if you want stdin, stdout &/or stderr to
1107 be set to usbtty.
1108
Wolfgang Denk386eda02006-06-14 18:14:56 +02001109 If you have a USB-IF assigned VendorID then you may wish to
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +02001110 define your own vendor specific values either in BoardName.h
Wolfgang Denk386eda02006-06-14 18:14:56 +02001111 or directly in usbd_vendor_info.h. If you don't define
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +02001112 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME,
1113 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot
1114 should pretend to be a Linux device to it's target host.
1115
1116 CONFIG_USBD_MANUFACTURER
1117 Define this string as the name of your company for
1118 - CONFIG_USBD_MANUFACTURER "my company"
Wolfgang Denk386eda02006-06-14 18:14:56 +02001119
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +02001120 CONFIG_USBD_PRODUCT_NAME
1121 Define this string as the name of your product
1122 - CONFIG_USBD_PRODUCT_NAME "acme usb device"
1123
1124 CONFIG_USBD_VENDORID
1125 Define this as your assigned Vendor ID from the USB
1126 Implementors Forum. This *must* be a genuine Vendor ID
1127 to avoid polluting the USB namespace.
1128 - CONFIG_USBD_VENDORID 0xFFFF
Wolfgang Denk386eda02006-06-14 18:14:56 +02001129
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +02001130 CONFIG_USBD_PRODUCTID
1131 Define this as the unique Product ID
1132 for your device
1133 - CONFIG_USBD_PRODUCTID 0xFFFF
wdenkc6097192002-11-03 00:24:07 +00001134
Igor Grinbergd70a5602011-12-12 12:08:35 +02001135- ULPI Layer Support:
1136 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via
1137 the generic ULPI layer. The generic layer accesses the ULPI PHY
1138 via the platform viewport, so you need both the genric layer and
1139 the viewport enabled. Currently only Chipidea/ARC based
1140 viewport is supported.
1141 To enable the ULPI layer support, define CONFIG_USB_ULPI and
1142 CONFIG_USB_ULPI_VIEWPORT in your board configuration file.
Lucas Stach6d365ea2012-10-01 00:44:35 +02001143 If your ULPI phy needs a different reference clock than the
1144 standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to
1145 the appropriate value in Hz.
wdenkc6097192002-11-03 00:24:07 +00001146
1147- MMC Support:
1148 The MMC controller on the Intel PXA is supported. To
1149 enable this define CONFIG_MMC. The MMC can be
1150 accessed from the boot prompt by mapping the device
1151 to physical memory similar to flash. Command line is
Jon Loeliger602ad3b2007-06-11 19:03:39 -05001152 enabled with CONFIG_CMD_MMC. The MMC driver also works with
1153 the FAT fs. This is enabled with CONFIG_CMD_FAT.
wdenkc6097192002-11-03 00:24:07 +00001154
Yoshihiro Shimodaafb35662011-07-04 22:21:22 +00001155 CONFIG_SH_MMCIF
1156 Support for Renesas on-chip MMCIF controller
1157
1158 CONFIG_SH_MMCIF_ADDR
1159 Define the base address of MMCIF registers
1160
1161 CONFIG_SH_MMCIF_CLK
1162 Define the clock frequency for MMCIF
1163
Pierre Aubert1fd93c62014-04-24 10:30:08 +02001164 CONFIG_SUPPORT_EMMC_BOOT
1165 Enable some additional features of the eMMC boot partitions.
1166
Tom Rinib3ba6e92013-03-14 05:32:47 +00001167- USB Device Firmware Update (DFU) class support:
Marek Vasutbb4059a2018-02-16 16:41:18 +01001168 CONFIG_DFU_OVER_USB
Tom Rinib3ba6e92013-03-14 05:32:47 +00001169 This enables the USB portion of the DFU USB class
1170
Tom Rinib3ba6e92013-03-14 05:32:47 +00001171 CONFIG_DFU_MMC
1172 This enables support for exposing (e)MMC devices via DFU.
1173
Pantelis Antoniouc6631762013-03-14 05:32:52 +00001174 CONFIG_DFU_NAND
1175 This enables support for exposing NAND devices via DFU.
1176
Afzal Mohammeda9479f02013-09-18 01:15:24 +05301177 CONFIG_DFU_RAM
1178 This enables support for exposing RAM via DFU.
1179 Note: DFU spec refer to non-volatile memory usage, but
1180 allow usages beyond the scope of spec - here RAM usage,
1181 one that would help mostly the developer.
1182
Heiko Schochere7e75c72013-06-12 06:05:51 +02001183 CONFIG_SYS_DFU_DATA_BUF_SIZE
1184 Dfu transfer uses a buffer before writing data to the
1185 raw storage device. Make the size (in bytes) of this buffer
1186 configurable. The size of this buffer is also configurable
1187 through the "dfu_bufsiz" environment variable.
1188
Pantelis Antoniouea2453d2013-03-14 05:32:48 +00001189 CONFIG_SYS_DFU_MAX_FILE_SIZE
1190 When updating files rather than the raw storage device,
1191 we use a static buffer to copy the file into and then write
1192 the buffer once we've been given the whole file. Define
1193 this to the maximum filesize (in bytes) for the buffer.
1194 Default is 4 MiB if undefined.
1195
Heiko Schocher001a8312014-03-18 08:09:56 +01001196 DFU_DEFAULT_POLL_TIMEOUT
1197 Poll timeout [ms], is the timeout a device can send to the
1198 host. The host must wait for this timeout before sending
1199 a subsequent DFU_GET_STATUS request to the device.
1200
1201 DFU_MANIFEST_POLL_TIMEOUT
1202 Poll timeout [ms], which the device sends to the host when
1203 entering dfuMANIFEST state. Host waits this timeout, before
1204 sending again an USB request to the device.
1205
wdenk6705d812004-08-02 23:22:59 +00001206- Journaling Flash filesystem support:
Simon Glassb2482df2016-10-02 18:00:59 -06001207 CONFIG_JFFS2_NAND
wdenk6705d812004-08-02 23:22:59 +00001208 Define these for a default partition on a NAND device
1209
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001210 CONFIG_SYS_JFFS2_FIRST_SECTOR,
1211 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS
wdenk6705d812004-08-02 23:22:59 +00001212 Define these for a default partition on a NOR device
1213
wdenkc6097192002-11-03 00:24:07 +00001214- Keyboard Support:
Simon Glass39f615e2015-11-11 10:05:47 -07001215 See Kconfig help for available keyboard drivers.
1216
1217 CONFIG_KEYBOARD
1218
1219 Define this to enable a custom keyboard support.
1220 This simply calls drv_keyboard_init() which must be
1221 defined in your board-specific files. This option is deprecated
1222 and is only used by novena. For new boards, use driver model
1223 instead.
wdenkc6097192002-11-03 00:24:07 +00001224
1225- Video support:
Timur Tabi7d3053f2011-02-15 17:09:19 -06001226 CONFIG_FSL_DIU_FB
Wolfgang Denk04e5ae72011-09-11 21:24:09 +02001227 Enable the Freescale DIU video driver. Reference boards for
Timur Tabi7d3053f2011-02-15 17:09:19 -06001228 SOCs that have a DIU should define this macro to enable DIU
1229 support, and should also define these other macros:
1230
1231 CONFIG_SYS_DIU_ADDR
1232 CONFIG_VIDEO
Timur Tabi7d3053f2011-02-15 17:09:19 -06001233 CONFIG_CFB_CONSOLE
1234 CONFIG_VIDEO_SW_CURSOR
1235 CONFIG_VGA_AS_SINGLE_DEVICE
1236 CONFIG_VIDEO_LOGO
1237 CONFIG_VIDEO_BMP_LOGO
1238
Timur Tabiba8e76b2011-04-11 14:18:22 -05001239 The DIU driver will look for the 'video-mode' environment
1240 variable, and if defined, enable the DIU as a console during
Fabio Estevam8eca9432016-04-02 11:53:18 -03001241 boot. See the documentation file doc/README.video for a
Timur Tabiba8e76b2011-04-11 14:18:22 -05001242 description of this variable.
Timur Tabi7d3053f2011-02-15 17:09:19 -06001243
wdenkc6097192002-11-03 00:24:07 +00001244- LCD Support: CONFIG_LCD
1245
1246 Define this to enable LCD support (for output to LCD
1247 display); also select one of the supported displays
1248 by defining one of these:
1249
Stelian Pop39cf4802008-05-09 21:57:18 +02001250 CONFIG_ATMEL_LCD:
1251
1252 HITACHI TX09D70VM1CCA, 3.5", 240x320.
1253
wdenkfd3103b2003-11-25 16:55:19 +00001254 CONFIG_NEC_NL6448AC33:
wdenkc6097192002-11-03 00:24:07 +00001255
wdenkfd3103b2003-11-25 16:55:19 +00001256 NEC NL6448AC33-18. Active, color, single scan.
wdenkc6097192002-11-03 00:24:07 +00001257
wdenkfd3103b2003-11-25 16:55:19 +00001258 CONFIG_NEC_NL6448BC20
wdenkc6097192002-11-03 00:24:07 +00001259
wdenkfd3103b2003-11-25 16:55:19 +00001260 NEC NL6448BC20-08. 6.5", 640x480.
1261 Active, color, single scan.
1262
1263 CONFIG_NEC_NL6448BC33_54
1264
1265 NEC NL6448BC33-54. 10.4", 640x480.
wdenkc6097192002-11-03 00:24:07 +00001266 Active, color, single scan.
1267
1268 CONFIG_SHARP_16x9
1269
1270 Sharp 320x240. Active, color, single scan.
1271 It isn't 16x9, and I am not sure what it is.
1272
1273 CONFIG_SHARP_LQ64D341
1274
1275 Sharp LQ64D341 display, 640x480.
1276 Active, color, single scan.
1277
1278 CONFIG_HLD1045
1279
1280 HLD1045 display, 640x480.
1281 Active, color, single scan.
1282
1283 CONFIG_OPTREX_BW
1284
1285 Optrex CBL50840-2 NF-FW 99 22 M5
1286 or
1287 Hitachi LMG6912RPFC-00T
1288 or
1289 Hitachi SP14Q002
1290
1291 320x240. Black & white.
1292
Simon Glass676d3192012-10-17 13:24:54 +00001293 CONFIG_LCD_ALIGNMENT
1294
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08001295 Normally the LCD is page-aligned (typically 4KB). If this is
Simon Glass676d3192012-10-17 13:24:54 +00001296 defined then the LCD will be aligned to this value instead.
1297 For ARM it is sometimes useful to use MMU_SECTION_SIZE
1298 here, since it is cheaper to change data cache settings on
1299 a per-section basis.
1300
1301
Hannes Petermaier604c7d42015-03-27 08:01:38 +01001302 CONFIG_LCD_ROTATION
1303
1304 Sometimes, for example if the display is mounted in portrait
1305 mode or even if it's mounted landscape but rotated by 180degree,
1306 we need to rotate our content of the display relative to the
1307 framebuffer, so that user can read the messages which are
1308 printed out.
1309 Once CONFIG_LCD_ROTATION is defined, the lcd_console will be
1310 initialized with a given rotation from "vl_rot" out of
1311 "vidinfo_t" which is provided by the board specific code.
1312 The value for vl_rot is coded as following (matching to
1313 fbcon=rotate:<n> linux-kernel commandline):
1314 0 = no rotation respectively 0 degree
1315 1 = 90 degree rotation
1316 2 = 180 degree rotation
1317 3 = 270 degree rotation
1318
1319 If CONFIG_LCD_ROTATION is not defined, the console will be
1320 initialized with 0degree rotation.
1321
Tom Wai-Hong Tam45d7f522012-09-28 15:11:16 +00001322 CONFIG_LCD_BMP_RLE8
1323
1324 Support drawing of RLE8-compressed bitmaps on the LCD.
1325
Tom Wai-Hong Tam735987c2012-12-05 14:46:40 +00001326 CONFIG_I2C_EDID
1327
1328 Enables an 'i2c edid' command which can read EDID
1329 information over I2C from an attached LCD display.
1330
wdenk7152b1d2003-09-05 23:19:14 +00001331- Splash Screen Support: CONFIG_SPLASH_SCREEN
wdenkd791b1d2003-04-20 14:04:18 +00001332
wdenk8bde7f72003-06-27 21:31:46 +00001333 If this option is set, the environment is checked for
1334 a variable "splashimage". If found, the usual display
1335 of logo, copyright and system information on the LCD
wdenke94d2cd2004-06-30 22:59:18 +00001336 is suppressed and the BMP image at the address
wdenk8bde7f72003-06-27 21:31:46 +00001337 specified in "splashimage" is loaded instead. The
1338 console is redirected to the "nulldev", too. This
1339 allows for a "silent" boot where a splash screen is
1340 loaded very quickly after power-on.
wdenkd791b1d2003-04-20 14:04:18 +00001341
Nikita Kiryanovc0880482013-02-24 21:28:43 +00001342 CONFIG_SPLASHIMAGE_GUARD
1343
1344 If this option is set, then U-Boot will prevent the environment
1345 variable "splashimage" from being set to a problematic address
Fabio Estevamab5645f2016-03-23 12:46:12 -03001346 (see doc/README.displaying-bmps).
Nikita Kiryanovc0880482013-02-24 21:28:43 +00001347 This option is useful for targets where, due to alignment
1348 restrictions, an improperly aligned BMP image will cause a data
1349 abort. If you think you will not have problems with unaligned
1350 accesses (for example because your toolchain prevents them)
1351 there is no need to set this option.
1352
Matthias Weisser1ca298c2009-07-09 16:07:30 +02001353 CONFIG_SPLASH_SCREEN_ALIGN
1354
1355 If this option is set the splash image can be freely positioned
1356 on the screen. Environment variable "splashpos" specifies the
1357 position as "x,y". If a positive number is given it is used as
1358 number of pixel from left/top. If a negative number is given it
1359 is used as number of pixel from right/bottom. You can also
1360 specify 'm' for centering the image.
1361
1362 Example:
1363 setenv splashpos m,m
1364 => image at center of screen
1365
1366 setenv splashpos 30,20
1367 => image at x = 30 and y = 20
1368
1369 setenv splashpos -10,m
1370 => vertically centered image
1371 at x = dspWidth - bmpWidth - 9
1372
Stefan Roese98f4a3d2005-09-22 09:04:17 +02001373- Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
1374
1375 If this option is set, additionally to standard BMP
1376 images, gzipped BMP images can be displayed via the
1377 splashscreen support or the bmp command.
1378
Anatolij Gustschind5011762010-03-15 14:50:25 +01001379- Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8
1380
1381 If this option is set, 8-bit RLE compressed BMP images
1382 can be displayed via the splashscreen support or the
1383 bmp command.
1384
wdenkc29fdfc2003-08-29 20:57:53 +00001385- Compression support:
Kees Cook8ef70472013-08-16 07:59:12 -07001386 CONFIG_GZIP
1387
1388 Enabled by default to support gzip compressed images.
1389
wdenkc29fdfc2003-08-29 20:57:53 +00001390 CONFIG_BZIP2
1391
1392 If this option is set, support for bzip2 compressed
1393 images is included. If not, only uncompressed and gzip
1394 compressed images are supported.
1395
wdenk42d1f032003-10-15 23:53:47 +00001396 NOTE: the bzip2 algorithm requires a lot of RAM, so
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001397 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should
wdenk42d1f032003-10-15 23:53:47 +00001398 be at least 4MB.
wdenkd791b1d2003-04-20 14:04:18 +00001399
wdenk17ea1172004-06-06 21:51:03 +00001400- MII/PHY support:
wdenk17ea1172004-06-06 21:51:03 +00001401 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
1402
1403 The clock frequency of the MII bus
1404
wdenk17ea1172004-06-06 21:51:03 +00001405 CONFIG_PHY_RESET_DELAY
1406
1407 Some PHY like Intel LXT971A need extra delay after
1408 reset before any MII register access is possible.
1409 For such PHY, set this option to the usec delay
1410 required. (minimum 300usec for LXT971A)
1411
1412 CONFIG_PHY_CMD_DELAY (ppc4xx)
1413
1414 Some PHY like Intel LXT971A need extra delay after
1415 command issued before MII status register can be read
1416
wdenkc6097192002-11-03 00:24:07 +00001417- IP address:
1418 CONFIG_IPADDR
1419
1420 Define a default value for the IP address to use for
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001421 the default Ethernet interface, in case this is not
wdenkc6097192002-11-03 00:24:07 +00001422 determined through e.g. bootp.
Wolfgang Denk1ebcd652011-10-26 10:21:22 +00001423 (Environment variable "ipaddr")
wdenkc6097192002-11-03 00:24:07 +00001424
1425- Server IP address:
1426 CONFIG_SERVERIP
1427
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001428 Defines a default value for the IP address of a TFTP
wdenkc6097192002-11-03 00:24:07 +00001429 server to contact when using the "tftboot" command.
Wolfgang Denk1ebcd652011-10-26 10:21:22 +00001430 (Environment variable "serverip")
wdenkc6097192002-11-03 00:24:07 +00001431
Robin Getz97cfe862009-07-21 12:15:28 -04001432 CONFIG_KEEP_SERVERADDR
1433
1434 Keeps the server's MAC address, in the env 'serveraddr'
1435 for passing to bootargs (like Linux's netconsole option)
1436
Wolfgang Denk1ebcd652011-10-26 10:21:22 +00001437- Gateway IP address:
1438 CONFIG_GATEWAYIP
1439
1440 Defines a default value for the IP address of the
1441 default router where packets to other networks are
1442 sent to.
1443 (Environment variable "gatewayip")
1444
1445- Subnet mask:
1446 CONFIG_NETMASK
1447
1448 Defines a default value for the subnet mask (or
1449 routing prefix) which is used to determine if an IP
1450 address belongs to the local subnet or needs to be
1451 forwarded through a router.
1452 (Environment variable "netmask")
1453
David Updegraff53a5c422007-06-11 10:41:07 -05001454- Multicast TFTP Mode:
1455 CONFIG_MCAST_TFTP
1456
1457 Defines whether you want to support multicast TFTP as per
1458 rfc-2090; for example to work with atftp. Lets lots of targets
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001459 tftp down the same boot image concurrently. Note: the Ethernet
David Updegraff53a5c422007-06-11 10:41:07 -05001460 driver in use must provide a function: mcast() to join/leave a
1461 multicast group.
1462
wdenkc6097192002-11-03 00:24:07 +00001463- BOOTP Recovery Mode:
1464 CONFIG_BOOTP_RANDOM_DELAY
1465
1466 If you have many targets in a network that try to
1467 boot using BOOTP, you may want to avoid that all
1468 systems send out BOOTP requests at precisely the same
1469 moment (which would happen for instance at recovery
1470 from a power failure, when all systems will try to
1471 boot, thus flooding the BOOTP server. Defining
1472 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
1473 inserted before sending out BOOTP requests. The
Wolfgang Denk6c33c782007-08-06 23:21:05 +02001474 following delays are inserted then:
wdenkc6097192002-11-03 00:24:07 +00001475
1476 1st BOOTP request: delay 0 ... 1 sec
1477 2nd BOOTP request: delay 0 ... 2 sec
1478 3rd BOOTP request: delay 0 ... 4 sec
1479 4th and following
1480 BOOTP requests: delay 0 ... 8 sec
1481
Thierry Reding92ac8ac2014-08-19 10:21:24 +02001482 CONFIG_BOOTP_ID_CACHE_SIZE
1483
1484 BOOTP packets are uniquely identified using a 32-bit ID. The
1485 server will copy the ID from client requests to responses and
1486 U-Boot will use this to determine if it is the destination of
1487 an incoming response. Some servers will check that addresses
1488 aren't in use before handing them out (usually using an ARP
1489 ping) and therefore take up to a few hundred milliseconds to
1490 respond. Network congestion may also influence the time it
1491 takes for a response to make it back to the client. If that
1492 time is too long, U-Boot will retransmit requests. In order
1493 to allow earlier responses to still be accepted after these
1494 retransmissions, U-Boot's BOOTP client keeps a small cache of
1495 IDs. The CONFIG_BOOTP_ID_CACHE_SIZE controls the size of this
1496 cache. The default is to keep IDs for up to four outstanding
1497 requests. Increasing this will allow U-Boot to accept offers
1498 from a BOOTP client in networks with unusually high latency.
1499
stroesefe389a82003-08-28 14:17:32 +00001500- DHCP Advanced Options:
Jon Loeliger1fe80d72007-07-09 22:08:34 -05001501 You can fine tune the DHCP functionality by defining
1502 CONFIG_BOOTP_* symbols:
stroesefe389a82003-08-28 14:17:32 +00001503
Jon Loeliger1fe80d72007-07-09 22:08:34 -05001504 CONFIG_BOOTP_NISDOMAIN
Jon Loeliger1fe80d72007-07-09 22:08:34 -05001505 CONFIG_BOOTP_BOOTFILESIZE
Jon Loeliger1fe80d72007-07-09 22:08:34 -05001506 CONFIG_BOOTP_SEND_HOSTNAME
1507 CONFIG_BOOTP_NTPSERVER
1508 CONFIG_BOOTP_TIMEOFFSET
1509 CONFIG_BOOTP_VENDOREX
Joe Hershberger2c00e092012-05-23 07:59:19 +00001510 CONFIG_BOOTP_MAY_FAIL
stroesefe389a82003-08-28 14:17:32 +00001511
Wilson Callan5d110f02007-07-28 10:56:13 -04001512 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip
1513 environment variable, not the BOOTP server.
stroesefe389a82003-08-28 14:17:32 +00001514
Joe Hershberger2c00e092012-05-23 07:59:19 +00001515 CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found
1516 after the configured retry count, the call will fail
1517 instead of starting over. This can be used to fail over
1518 to Link-local IP address configuration if the DHCP server
1519 is not available.
1520
stroesefe389a82003-08-28 14:17:32 +00001521 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
1522 to do a dynamic update of a DNS server. To do this, they
1523 need the hostname of the DHCP requester.
Wilson Callan5d110f02007-07-28 10:56:13 -04001524 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content
Jon Loeliger1fe80d72007-07-09 22:08:34 -05001525 of the "hostname" environment variable is passed as
1526 option 12 to the DHCP server.
stroesefe389a82003-08-28 14:17:32 +00001527
Aras Vaichasd9a2f412008-03-26 09:43:57 +11001528 CONFIG_BOOTP_DHCP_REQUEST_DELAY
1529
1530 A 32bit value in microseconds for a delay between
1531 receiving a "DHCP Offer" and sending the "DHCP Request".
1532 This fixes a problem with certain DHCP servers that don't
1533 respond 100% of the time to a "DHCP request". E.g. On an
1534 AT91RM9200 processor running at 180MHz, this delay needed
1535 to be *at least* 15,000 usec before a Windows Server 2003
1536 DHCP server would reply 100% of the time. I recommend at
1537 least 50,000 usec to be safe. The alternative is to hope
1538 that one of the retries will be successful but note that
1539 the DHCP timeout and retry process takes a longer than
1540 this delay.
1541
Joe Hershbergerd22c3382012-05-23 08:00:12 +00001542 - Link-local IP address negotiation:
1543 Negotiate with other link-local clients on the local network
1544 for an address that doesn't require explicit configuration.
1545 This is especially useful if a DHCP server cannot be guaranteed
1546 to exist in all environments that the device must operate.
1547
1548 See doc/README.link-local for more information.
1549
Prabhakar Kushwaha24acb832017-11-23 16:51:32 +05301550 - MAC address from environment variables
1551
1552 FDT_SEQ_MACADDR_FROM_ENV
1553
1554 Fix-up device tree with MAC addresses fetched sequentially from
1555 environment variables. This config work on assumption that
1556 non-usable ethernet node of device-tree are either not present
1557 or their status has been marked as "disabled".
1558
wdenka3d991b2004-04-15 21:48:45 +00001559 - CDP Options:
wdenk6e592382004-04-18 17:39:38 +00001560 CONFIG_CDP_DEVICE_ID
wdenka3d991b2004-04-15 21:48:45 +00001561
1562 The device id used in CDP trigger frames.
1563
1564 CONFIG_CDP_DEVICE_ID_PREFIX
1565
1566 A two character string which is prefixed to the MAC address
1567 of the device.
1568
1569 CONFIG_CDP_PORT_ID
1570
1571 A printf format string which contains the ascii name of
1572 the port. Normally is set to "eth%d" which sets
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001573 eth0 for the first Ethernet, eth1 for the second etc.
wdenka3d991b2004-04-15 21:48:45 +00001574
1575 CONFIG_CDP_CAPABILITIES
1576
1577 A 32bit integer which indicates the device capabilities;
1578 0x00000010 for a normal host which does not forwards.
1579
1580 CONFIG_CDP_VERSION
1581
1582 An ascii string containing the version of the software.
1583
1584 CONFIG_CDP_PLATFORM
1585
1586 An ascii string containing the name of the platform.
1587
1588 CONFIG_CDP_TRIGGER
1589
1590 A 32bit integer sent on the trigger.
1591
1592 CONFIG_CDP_POWER_CONSUMPTION
1593
1594 A 16bit integer containing the power consumption of the
1595 device in .1 of milliwatts.
1596
1597 CONFIG_CDP_APPLIANCE_VLAN_TYPE
1598
1599 A byte containing the id of the VLAN.
1600
Uri Mashiach79267ed2017-01-19 10:51:05 +02001601- Status LED: CONFIG_LED_STATUS
wdenkc6097192002-11-03 00:24:07 +00001602
1603 Several configurations allow to display the current
1604 status using a LED. For instance, the LED will blink
1605 fast while running U-Boot code, stop blinking as
1606 soon as a reply to a BOOTP request was received, and
1607 start blinking slow once the Linux kernel is running
1608 (supported by a status LED driver in the Linux
Uri Mashiach79267ed2017-01-19 10:51:05 +02001609 kernel). Defining CONFIG_LED_STATUS enables this
wdenkc6097192002-11-03 00:24:07 +00001610 feature in U-Boot.
1611
Igor Grinberg1df7bbb2013-11-08 01:03:50 +02001612 Additional options:
1613
Uri Mashiach79267ed2017-01-19 10:51:05 +02001614 CONFIG_LED_STATUS_GPIO
Igor Grinberg1df7bbb2013-11-08 01:03:50 +02001615 The status LED can be connected to a GPIO pin.
1616 In such cases, the gpio_led driver can be used as a
Uri Mashiach79267ed2017-01-19 10:51:05 +02001617 status LED backend implementation. Define CONFIG_LED_STATUS_GPIO
Igor Grinberg1df7bbb2013-11-08 01:03:50 +02001618 to include the gpio_led driver in the U-Boot binary.
1619
Igor Grinberg9dfdcdf2013-11-08 01:03:52 +02001620 CONFIG_GPIO_LED_INVERTED_TABLE
1621 Some GPIO connected LEDs may have inverted polarity in which
1622 case the GPIO high value corresponds to LED off state and
1623 GPIO low value corresponds to LED on state.
1624 In such cases CONFIG_GPIO_LED_INVERTED_TABLE may be defined
1625 with a list of GPIO LEDs that have inverted polarity.
1626
Heiko Schocher3f4978c2012-01-16 21:12:24 +00001627- I2C Support: CONFIG_SYS_I2C
wdenkc6097192002-11-03 00:24:07 +00001628
Heiko Schocher3f4978c2012-01-16 21:12:24 +00001629 This enable the NEW i2c subsystem, and will allow you to use
1630 i2c commands at the u-boot command line (as long as you set
1631 CONFIG_CMD_I2C in CONFIG_COMMANDS) and communicate with i2c
1632 based realtime clock chips or other i2c devices. See
1633 common/cmd_i2c.c for a description of the command line
1634 interface.
1635
1636 ported i2c driver to the new framework:
Heiko Schocherea818db2013-01-29 08:53:15 +01001637 - drivers/i2c/soft_i2c.c:
1638 - activate first bus with CONFIG_SYS_I2C_SOFT define
1639 CONFIG_SYS_I2C_SOFT_SPEED and CONFIG_SYS_I2C_SOFT_SLAVE
1640 for defining speed and slave address
1641 - activate second bus with I2C_SOFT_DECLARATIONS2 define
1642 CONFIG_SYS_I2C_SOFT_SPEED_2 and CONFIG_SYS_I2C_SOFT_SLAVE_2
1643 for defining speed and slave address
1644 - activate third bus with I2C_SOFT_DECLARATIONS3 define
1645 CONFIG_SYS_I2C_SOFT_SPEED_3 and CONFIG_SYS_I2C_SOFT_SLAVE_3
1646 for defining speed and slave address
1647 - activate fourth bus with I2C_SOFT_DECLARATIONS4 define
1648 CONFIG_SYS_I2C_SOFT_SPEED_4 and CONFIG_SYS_I2C_SOFT_SLAVE_4
1649 for defining speed and slave address
Heiko Schocher3f4978c2012-01-16 21:12:24 +00001650
Heiko Schocher00f792e2012-10-24 13:48:22 +02001651 - drivers/i2c/fsl_i2c.c:
1652 - activate i2c driver with CONFIG_SYS_I2C_FSL
1653 define CONFIG_SYS_FSL_I2C_OFFSET for setting the register
1654 offset CONFIG_SYS_FSL_I2C_SPEED for the i2c speed and
1655 CONFIG_SYS_FSL_I2C_SLAVE for the slave addr of the first
1656 bus.
Wolfgang Denk93e14592013-10-04 17:43:24 +02001657 - If your board supports a second fsl i2c bus, define
Heiko Schocher00f792e2012-10-24 13:48:22 +02001658 CONFIG_SYS_FSL_I2C2_OFFSET for the register offset
1659 CONFIG_SYS_FSL_I2C2_SPEED for the speed and
1660 CONFIG_SYS_FSL_I2C2_SLAVE for the slave address of the
1661 second bus.
1662
Simon Glass1f2ba722012-10-30 07:28:53 +00001663 - drivers/i2c/tegra_i2c.c:
Nobuhiro Iwamatsu10cee512013-10-11 16:23:53 +09001664 - activate this driver with CONFIG_SYS_I2C_TEGRA
1665 - This driver adds 4 i2c buses with a fix speed from
1666 100000 and the slave addr 0!
Simon Glass1f2ba722012-10-30 07:28:53 +00001667
Dirk Eibach880540d2013-04-25 02:40:01 +00001668 - drivers/i2c/ppc4xx_i2c.c
1669 - activate this driver with CONFIG_SYS_I2C_PPC4XX
1670 - CONFIG_SYS_I2C_PPC4XX_CH0 activate hardware channel 0
1671 - CONFIG_SYS_I2C_PPC4XX_CH1 activate hardware channel 1
1672
tremfac96402013-09-21 18:13:35 +02001673 - drivers/i2c/i2c_mxc.c
1674 - activate this driver with CONFIG_SYS_I2C_MXC
Albert ARIBAUD \\(3ADEV\\)03544c62015-09-21 22:43:38 +02001675 - enable bus 1 with CONFIG_SYS_I2C_MXC_I2C1
1676 - enable bus 2 with CONFIG_SYS_I2C_MXC_I2C2
1677 - enable bus 3 with CONFIG_SYS_I2C_MXC_I2C3
1678 - enable bus 4 with CONFIG_SYS_I2C_MXC_I2C4
tremfac96402013-09-21 18:13:35 +02001679 - define speed for bus 1 with CONFIG_SYS_MXC_I2C1_SPEED
1680 - define slave for bus 1 with CONFIG_SYS_MXC_I2C1_SLAVE
1681 - define speed for bus 2 with CONFIG_SYS_MXC_I2C2_SPEED
1682 - define slave for bus 2 with CONFIG_SYS_MXC_I2C2_SLAVE
1683 - define speed for bus 3 with CONFIG_SYS_MXC_I2C3_SPEED
1684 - define slave for bus 3 with CONFIG_SYS_MXC_I2C3_SLAVE
Albert ARIBAUD \\(3ADEV\\)03544c62015-09-21 22:43:38 +02001685 - define speed for bus 4 with CONFIG_SYS_MXC_I2C4_SPEED
1686 - define slave for bus 4 with CONFIG_SYS_MXC_I2C4_SLAVE
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08001687 If those defines are not set, default value is 100000
tremfac96402013-09-21 18:13:35 +02001688 for speed, and 0 for slave.
1689
Nobuhiro Iwamatsu1086bfa2013-09-27 16:58:30 +09001690 - drivers/i2c/rcar_i2c.c:
1691 - activate this driver with CONFIG_SYS_I2C_RCAR
1692 - This driver adds 4 i2c buses
1693
1694 - CONFIG_SYS_RCAR_I2C0_BASE for setting the register channel 0
1695 - CONFIG_SYS_RCAR_I2C0_SPEED for for the speed channel 0
1696 - CONFIG_SYS_RCAR_I2C1_BASE for setting the register channel 1
1697 - CONFIG_SYS_RCAR_I2C1_SPEED for for the speed channel 1
1698 - CONFIG_SYS_RCAR_I2C2_BASE for setting the register channel 2
1699 - CONFIG_SYS_RCAR_I2C2_SPEED for for the speed channel 2
1700 - CONFIG_SYS_RCAR_I2C3_BASE for setting the register channel 3
1701 - CONFIG_SYS_RCAR_I2C3_SPEED for for the speed channel 3
1702 - CONFIF_SYS_RCAR_I2C_NUM_CONTROLLERS for number of i2c buses
1703
Nobuhiro Iwamatsu2035d772013-10-29 13:33:51 +09001704 - drivers/i2c/sh_i2c.c:
1705 - activate this driver with CONFIG_SYS_I2C_SH
1706 - This driver adds from 2 to 5 i2c buses
1707
1708 - CONFIG_SYS_I2C_SH_BASE0 for setting the register channel 0
1709 - CONFIG_SYS_I2C_SH_SPEED0 for for the speed channel 0
1710 - CONFIG_SYS_I2C_SH_BASE1 for setting the register channel 1
1711 - CONFIG_SYS_I2C_SH_SPEED1 for for the speed channel 1
1712 - CONFIG_SYS_I2C_SH_BASE2 for setting the register channel 2
1713 - CONFIG_SYS_I2C_SH_SPEED2 for for the speed channel 2
1714 - CONFIG_SYS_I2C_SH_BASE3 for setting the register channel 3
1715 - CONFIG_SYS_I2C_SH_SPEED3 for for the speed channel 3
1716 - CONFIG_SYS_I2C_SH_BASE4 for setting the register channel 4
1717 - CONFIG_SYS_I2C_SH_SPEED4 for for the speed channel 4
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08001718 - CONFIG_SYS_I2C_SH_NUM_CONTROLLERS for number of i2c buses
Nobuhiro Iwamatsu2035d772013-10-29 13:33:51 +09001719
Heiko Schocher6789e842013-10-22 11:03:18 +02001720 - drivers/i2c/omap24xx_i2c.c
1721 - activate this driver with CONFIG_SYS_I2C_OMAP24XX
1722 - CONFIG_SYS_OMAP24_I2C_SPEED speed channel 0
1723 - CONFIG_SYS_OMAP24_I2C_SLAVE slave addr channel 0
1724 - CONFIG_SYS_OMAP24_I2C_SPEED1 speed channel 1
1725 - CONFIG_SYS_OMAP24_I2C_SLAVE1 slave addr channel 1
1726 - CONFIG_SYS_OMAP24_I2C_SPEED2 speed channel 2
1727 - CONFIG_SYS_OMAP24_I2C_SLAVE2 slave addr channel 2
1728 - CONFIG_SYS_OMAP24_I2C_SPEED3 speed channel 3
1729 - CONFIG_SYS_OMAP24_I2C_SLAVE3 slave addr channel 3
1730 - CONFIG_SYS_OMAP24_I2C_SPEED4 speed channel 4
1731 - CONFIG_SYS_OMAP24_I2C_SLAVE4 slave addr channel 4
1732
Heiko Schocher0bdffe72013-11-08 07:30:53 +01001733 - drivers/i2c/zynq_i2c.c
1734 - activate this driver with CONFIG_SYS_I2C_ZYNQ
1735 - set CONFIG_SYS_I2C_ZYNQ_SPEED for speed setting
1736 - set CONFIG_SYS_I2C_ZYNQ_SLAVE for slave addr
1737
Naveen Krishna Che717fc62013-12-06 12:12:38 +05301738 - drivers/i2c/s3c24x0_i2c.c:
1739 - activate this driver with CONFIG_SYS_I2C_S3C24X0
1740 - This driver adds i2c buses (11 for Exynos5250, Exynos5420
1741 9 i2c buses for Exynos4 and 1 for S3C24X0 SoCs from Samsung)
1742 with a fix speed from 100000 and the slave addr 0!
1743
Dirk Eibachb46226b2014-07-03 09:28:18 +02001744 - drivers/i2c/ihs_i2c.c
1745 - activate this driver with CONFIG_SYS_I2C_IHS
1746 - CONFIG_SYS_I2C_IHS_CH0 activate hardware channel 0
1747 - CONFIG_SYS_I2C_IHS_SPEED_0 speed channel 0
1748 - CONFIG_SYS_I2C_IHS_SLAVE_0 slave addr channel 0
1749 - CONFIG_SYS_I2C_IHS_CH1 activate hardware channel 1
1750 - CONFIG_SYS_I2C_IHS_SPEED_1 speed channel 1
1751 - CONFIG_SYS_I2C_IHS_SLAVE_1 slave addr channel 1
1752 - CONFIG_SYS_I2C_IHS_CH2 activate hardware channel 2
1753 - CONFIG_SYS_I2C_IHS_SPEED_2 speed channel 2
1754 - CONFIG_SYS_I2C_IHS_SLAVE_2 slave addr channel 2
1755 - CONFIG_SYS_I2C_IHS_CH3 activate hardware channel 3
1756 - CONFIG_SYS_I2C_IHS_SPEED_3 speed channel 3
1757 - CONFIG_SYS_I2C_IHS_SLAVE_3 slave addr channel 3
Dirk Eibach071be892015-10-28 11:46:22 +01001758 - activate dual channel with CONFIG_SYS_I2C_IHS_DUAL
1759 - CONFIG_SYS_I2C_IHS_SPEED_0_1 speed channel 0_1
1760 - CONFIG_SYS_I2C_IHS_SLAVE_0_1 slave addr channel 0_1
1761 - CONFIG_SYS_I2C_IHS_SPEED_1_1 speed channel 1_1
1762 - CONFIG_SYS_I2C_IHS_SLAVE_1_1 slave addr channel 1_1
1763 - CONFIG_SYS_I2C_IHS_SPEED_2_1 speed channel 2_1
1764 - CONFIG_SYS_I2C_IHS_SLAVE_2_1 slave addr channel 2_1
1765 - CONFIG_SYS_I2C_IHS_SPEED_3_1 speed channel 3_1
1766 - CONFIG_SYS_I2C_IHS_SLAVE_3_1 slave addr channel 3_1
Dirk Eibachb46226b2014-07-03 09:28:18 +02001767
Heiko Schocher3f4978c2012-01-16 21:12:24 +00001768 additional defines:
1769
1770 CONFIG_SYS_NUM_I2C_BUSES
Simon Glass945a18e2016-10-02 18:01:05 -06001771 Hold the number of i2c buses you want to use.
Heiko Schocher3f4978c2012-01-16 21:12:24 +00001772
1773 CONFIG_SYS_I2C_DIRECT_BUS
1774 define this, if you don't use i2c muxes on your hardware.
1775 if CONFIG_SYS_I2C_MAX_HOPS is not defined or == 0 you can
1776 omit this define.
1777
1778 CONFIG_SYS_I2C_MAX_HOPS
1779 define how many muxes are maximal consecutively connected
1780 on one i2c bus. If you not use i2c muxes, omit this
1781 define.
1782
1783 CONFIG_SYS_I2C_BUSES
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08001784 hold a list of buses you want to use, only used if
Heiko Schocher3f4978c2012-01-16 21:12:24 +00001785 CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example
1786 a board with CONFIG_SYS_I2C_MAX_HOPS = 1 and
1787 CONFIG_SYS_NUM_I2C_BUSES = 9:
1788
1789 CONFIG_SYS_I2C_BUSES {{0, {I2C_NULL_HOP}}, \
1790 {0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \
1791 {0, {{I2C_MUX_PCA9547, 0x70, 2}}}, \
1792 {0, {{I2C_MUX_PCA9547, 0x70, 3}}}, \
1793 {0, {{I2C_MUX_PCA9547, 0x70, 4}}}, \
1794 {0, {{I2C_MUX_PCA9547, 0x70, 5}}}, \
1795 {1, {I2C_NULL_HOP}}, \
1796 {1, {{I2C_MUX_PCA9544, 0x72, 1}}}, \
1797 {1, {{I2C_MUX_PCA9544, 0x72, 2}}}, \
1798 }
1799
1800 which defines
1801 bus 0 on adapter 0 without a mux
Heiko Schocherea818db2013-01-29 08:53:15 +01001802 bus 1 on adapter 0 with a PCA9547 on address 0x70 port 1
1803 bus 2 on adapter 0 with a PCA9547 on address 0x70 port 2
1804 bus 3 on adapter 0 with a PCA9547 on address 0x70 port 3
1805 bus 4 on adapter 0 with a PCA9547 on address 0x70 port 4
1806 bus 5 on adapter 0 with a PCA9547 on address 0x70 port 5
Heiko Schocher3f4978c2012-01-16 21:12:24 +00001807 bus 6 on adapter 1 without a mux
Heiko Schocherea818db2013-01-29 08:53:15 +01001808 bus 7 on adapter 1 with a PCA9544 on address 0x72 port 1
1809 bus 8 on adapter 1 with a PCA9544 on address 0x72 port 2
Heiko Schocher3f4978c2012-01-16 21:12:24 +00001810
1811 If you do not have i2c muxes on your board, omit this define.
1812
Simon Glassce3b5d62017-05-12 21:10:00 -06001813- Legacy I2C Support:
Heiko Schocherea818db2013-01-29 08:53:15 +01001814 If you use the software i2c interface (CONFIG_SYS_I2C_SOFT)
wdenkb37c7e52003-06-30 16:24:52 +00001815 then the following macros need to be defined (examples are
1816 from include/configs/lwmon.h):
wdenkc6097192002-11-03 00:24:07 +00001817
1818 I2C_INIT
1819
wdenkb37c7e52003-06-30 16:24:52 +00001820 (Optional). Any commands necessary to enable the I2C
wdenk43d96162003-03-06 00:02:04 +00001821 controller or configure ports.
wdenkc6097192002-11-03 00:24:07 +00001822
wdenkba56f622004-02-06 23:19:44 +00001823 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
wdenkb37c7e52003-06-30 16:24:52 +00001824
wdenkc6097192002-11-03 00:24:07 +00001825 I2C_ACTIVE
1826
1827 The code necessary to make the I2C data line active
1828 (driven). If the data line is open collector, this
1829 define can be null.
1830
wdenkb37c7e52003-06-30 16:24:52 +00001831 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
1832
wdenkc6097192002-11-03 00:24:07 +00001833 I2C_TRISTATE
1834
1835 The code necessary to make the I2C data line tri-stated
1836 (inactive). If the data line is open collector, this
1837 define can be null.
1838
wdenkb37c7e52003-06-30 16:24:52 +00001839 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
1840
wdenkc6097192002-11-03 00:24:07 +00001841 I2C_READ
1842
York Sun472d5462013-04-01 11:29:11 -07001843 Code that returns true if the I2C data line is high,
1844 false if it is low.
wdenkc6097192002-11-03 00:24:07 +00001845
wdenkb37c7e52003-06-30 16:24:52 +00001846 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
1847
wdenkc6097192002-11-03 00:24:07 +00001848 I2C_SDA(bit)
1849
York Sun472d5462013-04-01 11:29:11 -07001850 If <bit> is true, sets the I2C data line high. If it
1851 is false, it clears it (low).
wdenkc6097192002-11-03 00:24:07 +00001852
wdenkb37c7e52003-06-30 16:24:52 +00001853 eg: #define I2C_SDA(bit) \
wdenk2535d602003-07-17 23:16:40 +00001854 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
wdenkba56f622004-02-06 23:19:44 +00001855 else immr->im_cpm.cp_pbdat &= ~PB_SDA
wdenkb37c7e52003-06-30 16:24:52 +00001856
wdenkc6097192002-11-03 00:24:07 +00001857 I2C_SCL(bit)
1858
York Sun472d5462013-04-01 11:29:11 -07001859 If <bit> is true, sets the I2C clock line high. If it
1860 is false, it clears it (low).
wdenkc6097192002-11-03 00:24:07 +00001861
wdenkb37c7e52003-06-30 16:24:52 +00001862 eg: #define I2C_SCL(bit) \
wdenk2535d602003-07-17 23:16:40 +00001863 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
wdenkba56f622004-02-06 23:19:44 +00001864 else immr->im_cpm.cp_pbdat &= ~PB_SCL
wdenkb37c7e52003-06-30 16:24:52 +00001865
wdenkc6097192002-11-03 00:24:07 +00001866 I2C_DELAY
1867
1868 This delay is invoked four times per clock cycle so this
1869 controls the rate of data transfer. The data rate thus
wdenkb37c7e52003-06-30 16:24:52 +00001870 is 1 / (I2C_DELAY * 4). Often defined to be something
wdenk945af8d2003-07-16 21:53:01 +00001871 like:
1872
wdenkb37c7e52003-06-30 16:24:52 +00001873 #define I2C_DELAY udelay(2)
wdenkc6097192002-11-03 00:24:07 +00001874
Mike Frysinger793b5722010-07-21 13:38:02 -04001875 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA
1876
1877 If your arch supports the generic GPIO framework (asm/gpio.h),
1878 then you may alternatively define the two GPIOs that are to be
1879 used as SCL / SDA. Any of the previous I2C_xxx macros will
1880 have GPIO-based defaults assigned to them as appropriate.
1881
1882 You should define these to the GPIO value as given directly to
1883 the generic GPIO functions.
1884
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001885 CONFIG_SYS_I2C_INIT_BOARD
wdenk47cd00f2003-03-06 13:39:27 +00001886
wdenk8bde7f72003-06-27 21:31:46 +00001887 When a board is reset during an i2c bus transfer
1888 chips might think that the current transfer is still
1889 in progress. On some boards it is possible to access
1890 the i2c SCLK line directly, either by using the
1891 processor pin as a GPIO or by having a second pin
1892 connected to the bus. If this option is defined a
1893 custom i2c_init_board() routine in boards/xxx/board.c
1894 is run early in the boot sequence.
wdenk47cd00f2003-03-06 13:39:27 +00001895
Ben Warrenbb99ad62006-09-07 16:50:54 -04001896 CONFIG_I2C_MULTI_BUS
1897
1898 This option allows the use of multiple I2C buses, each of which
Wolfgang Denkc0f40852011-10-26 10:21:21 +00001899 must have a controller. At any point in time, only one bus is
1900 active. To switch to a different bus, use the 'i2c dev' command.
Ben Warrenbb99ad62006-09-07 16:50:54 -04001901 Note that bus numbering is zero-based.
1902
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001903 CONFIG_SYS_I2C_NOPROBES
Ben Warrenbb99ad62006-09-07 16:50:54 -04001904
1905 This option specifies a list of I2C devices that will be skipped
Wolfgang Denkc0f40852011-10-26 10:21:21 +00001906 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS
Peter Tyser0f89c542009-04-18 22:34:03 -05001907 is set, specify a list of bus-device pairs. Otherwise, specify
1908 a 1D array of device addresses
Ben Warrenbb99ad62006-09-07 16:50:54 -04001909
1910 e.g.
1911 #undef CONFIG_I2C_MULTI_BUS
Wolfgang Denkc0f40852011-10-26 10:21:21 +00001912 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68}
Ben Warrenbb99ad62006-09-07 16:50:54 -04001913
1914 will skip addresses 0x50 and 0x68 on a board with one I2C bus
1915
Wolfgang Denkc0f40852011-10-26 10:21:21 +00001916 #define CONFIG_I2C_MULTI_BUS
Simon Glass945a18e2016-10-02 18:01:05 -06001917 #define CONFIG_SYS_I2C_NOPROBES {{0,0x50},{0,0x68},{1,0x54}}
Ben Warrenbb99ad62006-09-07 16:50:54 -04001918
1919 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1
1920
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001921 CONFIG_SYS_SPD_BUS_NUM
Timur Tabibe5e6182006-11-03 19:15:00 -06001922
1923 If defined, then this indicates the I2C bus number for DDR SPD.
1924 If not defined, then U-Boot assumes that SPD is on I2C bus 0.
1925
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001926 CONFIG_SYS_RTC_BUS_NUM
Stefan Roese0dc018e2007-02-20 10:51:26 +01001927
1928 If defined, then this indicates the I2C bus number for the RTC.
1929 If not defined, then U-Boot assumes that RTC is on I2C bus 0.
1930
Andrew Dyer2ac69852008-12-29 17:36:01 -06001931 CONFIG_SOFT_I2C_READ_REPEATED_START
1932
1933 defining this will force the i2c_read() function in
1934 the soft_i2c driver to perform an I2C repeated start
1935 between writing the address pointer and reading the
1936 data. If this define is omitted the default behaviour
1937 of doing a stop-start sequence will be used. Most I2C
1938 devices can use either method, but some require one or
1939 the other.
Timur Tabibe5e6182006-11-03 19:15:00 -06001940
wdenkc6097192002-11-03 00:24:07 +00001941- SPI Support: CONFIG_SPI
1942
1943 Enables SPI driver (so far only tested with
1944 SPI EEPROM, also an instance works with Crystal A/D and
1945 D/As on the SACSng board)
1946
wdenkc6097192002-11-03 00:24:07 +00001947 CONFIG_SOFT_SPI
1948
wdenk43d96162003-03-06 00:02:04 +00001949 Enables a software (bit-bang) SPI driver rather than
1950 using hardware support. This is a general purpose
1951 driver that only requires three general I/O port pins
1952 (two outputs, one input) to function. If this is
1953 defined, the board configuration must define several
1954 SPI configuration items (port pins to use, etc). For
1955 an example, see include/configs/sacsng.h.
wdenkc6097192002-11-03 00:24:07 +00001956
Ben Warren04a9e112008-01-16 22:37:35 -05001957 CONFIG_HARD_SPI
1958
1959 Enables a hardware SPI driver for general-purpose reads
1960 and writes. As with CONFIG_SOFT_SPI, the board configuration
1961 must define a list of chip-select function pointers.
Wolfgang Denkc0f40852011-10-26 10:21:21 +00001962 Currently supported on some MPC8xxx processors. For an
Ben Warren04a9e112008-01-16 22:37:35 -05001963 example, see include/configs/mpc8349emds.h.
1964
Heiko Schocherf659b572014-07-14 10:22:11 +02001965 CONFIG_SYS_SPI_MXC_WAIT
1966 Timeout for waiting until spi transfer completed.
1967 default: (CONFIG_SYS_HZ/100) /* 10 ms */
1968
Matthias Fuchs01335022007-12-27 17:12:34 +01001969- FPGA Support: CONFIG_FPGA
1970
1971 Enables FPGA subsystem.
1972
1973 CONFIG_FPGA_<vendor>
1974
1975 Enables support for specific chip vendors.
1976 (ALTERA, XILINX)
1977
1978 CONFIG_FPGA_<family>
1979
1980 Enables support for FPGA family.
1981 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
1982
1983 CONFIG_FPGA_COUNT
wdenkc6097192002-11-03 00:24:07 +00001984
wdenk43d96162003-03-06 00:02:04 +00001985 Specify the number of FPGA devices to support.
wdenkc6097192002-11-03 00:24:07 +00001986
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001987 CONFIG_SYS_FPGA_PROG_FEEDBACK
wdenkc6097192002-11-03 00:24:07 +00001988
wdenk8bde7f72003-06-27 21:31:46 +00001989 Enable printing of hash marks during FPGA configuration.
wdenkc6097192002-11-03 00:24:07 +00001990
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001991 CONFIG_SYS_FPGA_CHECK_BUSY
wdenkc6097192002-11-03 00:24:07 +00001992
wdenk43d96162003-03-06 00:02:04 +00001993 Enable checks on FPGA configuration interface busy
1994 status by the configuration function. This option
1995 will require a board or device specific function to
1996 be written.
wdenkc6097192002-11-03 00:24:07 +00001997
1998 CONFIG_FPGA_DELAY
1999
2000 If defined, a function that provides delays in the FPGA
2001 configuration driver.
2002
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002003 CONFIG_SYS_FPGA_CHECK_CTRLC
wdenkc6097192002-11-03 00:24:07 +00002004 Allow Control-C to interrupt FPGA configuration
2005
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002006 CONFIG_SYS_FPGA_CHECK_ERROR
wdenkc6097192002-11-03 00:24:07 +00002007
wdenk43d96162003-03-06 00:02:04 +00002008 Check for configuration errors during FPGA bitfile
2009 loading. For example, abort during Virtex II
2010 configuration if the INIT_B line goes low (which
2011 indicated a CRC error).
wdenkc6097192002-11-03 00:24:07 +00002012
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002013 CONFIG_SYS_FPGA_WAIT_INIT
wdenkc6097192002-11-03 00:24:07 +00002014
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08002015 Maximum time to wait for the INIT_B line to de-assert
2016 after PROB_B has been de-asserted during a Virtex II
wdenk43d96162003-03-06 00:02:04 +00002017 FPGA configuration sequence. The default time is 500
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002018 ms.
wdenkc6097192002-11-03 00:24:07 +00002019
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002020 CONFIG_SYS_FPGA_WAIT_BUSY
wdenkc6097192002-11-03 00:24:07 +00002021
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08002022 Maximum time to wait for BUSY to de-assert during
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002023 Virtex II FPGA configuration. The default is 5 ms.
wdenkc6097192002-11-03 00:24:07 +00002024
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002025 CONFIG_SYS_FPGA_WAIT_CONFIG
wdenkc6097192002-11-03 00:24:07 +00002026
wdenk43d96162003-03-06 00:02:04 +00002027 Time to wait after FPGA configuration. The default is
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002028 200 ms.
wdenkc6097192002-11-03 00:24:07 +00002029
2030- Configuration Management:
Stefan Roeseb2b8a692014-10-22 12:13:24 +02002031 CONFIG_BUILD_TARGET
2032
2033 Some SoCs need special image types (e.g. U-Boot binary
2034 with a special header) as build targets. By defining
2035 CONFIG_BUILD_TARGET in the SoC / board header, this
2036 special image will be automatically built upon calling
Simon Glass6de80f22016-07-27 20:33:08 -06002037 make / buildman.
Stefan Roeseb2b8a692014-10-22 12:13:24 +02002038
wdenkc6097192002-11-03 00:24:07 +00002039 CONFIG_IDENT_STRING
2040
wdenk43d96162003-03-06 00:02:04 +00002041 If defined, this string will be added to the U-Boot
2042 version information (U_BOOT_VERSION)
wdenkc6097192002-11-03 00:24:07 +00002043
2044- Vendor Parameter Protection:
2045
wdenk43d96162003-03-06 00:02:04 +00002046 U-Boot considers the values of the environment
2047 variables "serial#" (Board Serial Number) and
wdenk7152b1d2003-09-05 23:19:14 +00002048 "ethaddr" (Ethernet Address) to be parameters that
wdenk43d96162003-03-06 00:02:04 +00002049 are set once by the board vendor / manufacturer, and
2050 protects these variables from casual modification by
2051 the user. Once set, these variables are read-only,
2052 and write or delete attempts are rejected. You can
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002053 change this behaviour:
wdenkc6097192002-11-03 00:24:07 +00002054
2055 If CONFIG_ENV_OVERWRITE is #defined in your config
2056 file, the write protection for vendor parameters is
wdenk47cd00f2003-03-06 13:39:27 +00002057 completely disabled. Anybody can change or delete
wdenkc6097192002-11-03 00:24:07 +00002058 these parameters.
2059
Joe Hershberger92ac5202015-05-04 14:55:14 -05002060 Alternatively, if you define _both_ an ethaddr in the
2061 default env _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002062 Ethernet address is installed in the environment,
wdenkc6097192002-11-03 00:24:07 +00002063 which can be changed exactly ONCE by the user. [The
2064 serial# is unaffected by this, i. e. it remains
2065 read-only.]
2066
Joe Hershberger25980902012-12-11 22:16:31 -06002067 The same can be accomplished in a more flexible way
2068 for any variable by configuring the type of access
2069 to allow for those variables in the ".flags" variable
2070 or define CONFIG_ENV_FLAGS_LIST_STATIC.
2071
wdenkc6097192002-11-03 00:24:07 +00002072- Protected RAM:
2073 CONFIG_PRAM
2074
2075 Define this variable to enable the reservation of
2076 "protected RAM", i. e. RAM which is not overwritten
2077 by U-Boot. Define CONFIG_PRAM to hold the number of
2078 kB you want to reserve for pRAM. You can overwrite
2079 this default value by defining an environment
2080 variable "pram" to the number of kB you want to
2081 reserve. Note that the board info structure will
2082 still show the full amount of RAM. If pRAM is
2083 reserved, a new environment variable "mem" will
2084 automatically be defined to hold the amount of
2085 remaining RAM in a form that can be passed as boot
2086 argument to Linux, for instance like that:
2087
Wolfgang Denkfe126d82005-11-20 21:40:11 +01002088 setenv bootargs ... mem=\${mem}
wdenkc6097192002-11-03 00:24:07 +00002089 saveenv
2090
2091 This way you can tell Linux not to use this memory,
2092 either, which results in a memory region that will
2093 not be affected by reboots.
2094
2095 *WARNING* If your board configuration uses automatic
2096 detection of the RAM size, you must make sure that
2097 this memory test is non-destructive. So far, the
2098 following board configurations are known to be
2099 "pRAM-clean":
2100
Heiko Schocher5b8e76c2017-06-07 17:33:09 +02002101 IVMS8, IVML24, SPD8xx,
Wolfgang Denk1b0757e2012-10-24 02:36:15 +00002102 HERMES, IP860, RPXlite, LWMON,
Heiko Schocher2eb48ff2017-06-07 17:33:10 +02002103 FLAGADM
wdenkc6097192002-11-03 00:24:07 +00002104
Gabe Black40fef042012-12-02 04:55:18 +00002105- Access to physical memory region (> 4GB)
2106 Some basic support is provided for operations on memory not
2107 normally accessible to U-Boot - e.g. some architectures
2108 support access to more than 4GB of memory on 32-bit
2109 machines using physical address extension or similar.
2110 Define CONFIG_PHYSMEM to access this basic support, which
2111 currently only supports clearing the memory.
2112
wdenkc6097192002-11-03 00:24:07 +00002113- Error Recovery:
wdenkc6097192002-11-03 00:24:07 +00002114 CONFIG_NET_RETRY_COUNT
2115
wdenk43d96162003-03-06 00:02:04 +00002116 This variable defines the number of retries for
2117 network operations like ARP, RARP, TFTP, or BOOTP
2118 before giving up the operation. If not defined, a
2119 default value of 5 is used.
wdenkc6097192002-11-03 00:24:07 +00002120
Guennadi Liakhovetski40cb90e2008-04-03 17:04:19 +02002121 CONFIG_ARP_TIMEOUT
2122
2123 Timeout waiting for an ARP reply in milliseconds.
2124
Tetsuyuki Kobayashi48a3e992012-07-03 22:25:21 +00002125 CONFIG_NFS_TIMEOUT
2126
2127 Timeout in milliseconds used in NFS protocol.
2128 If you encounter "ERROR: Cannot umount" in nfs command,
2129 try longer timeout such as
2130 #define CONFIG_NFS_TIMEOUT 10000UL
2131
wdenkc6097192002-11-03 00:24:07 +00002132- Command Interpreter:
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002133 CONFIG_SYS_PROMPT_HUSH_PS2
wdenkc6097192002-11-03 00:24:07 +00002134
2135 This defines the secondary prompt string, which is
2136 printed when the command interpreter needs more input
2137 to complete a command. Usually "> ".
2138
2139 Note:
2140
wdenk8bde7f72003-06-27 21:31:46 +00002141 In the current implementation, the local variables
2142 space and global environment variables space are
2143 separated. Local variables are those you define by
2144 simply typing `name=value'. To access a local
2145 variable later on, you have write `$name' or
2146 `${name}'; to execute the contents of a variable
2147 directly type `$name' at the command prompt.
wdenkc6097192002-11-03 00:24:07 +00002148
wdenk43d96162003-03-06 00:02:04 +00002149 Global environment variables are those you use
2150 setenv/printenv to work with. To run a command stored
2151 in such a variable, you need to use the run command,
2152 and you must not use the '$' sign to access them.
wdenkc6097192002-11-03 00:24:07 +00002153
2154 To store commands and special characters in a
2155 variable, please use double quotation marks
2156 surrounding the whole text of the variable, instead
2157 of the backslashes before semicolons and special
2158 symbols.
2159
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08002160- Command Line Editing and History:
Marek Vasutf3b267b2016-01-27 04:47:55 +01002161 CONFIG_CMDLINE_PS_SUPPORT
2162
2163 Enable support for changing the command prompt string
2164 at run-time. Only static string is supported so far.
2165 The string is obtained from environment variables PS1
2166 and PS2.
2167
wdenka8c7c702003-12-06 19:49:23 +00002168- Default Environment:
wdenkc6097192002-11-03 00:24:07 +00002169 CONFIG_EXTRA_ENV_SETTINGS
2170
wdenk43d96162003-03-06 00:02:04 +00002171 Define this to contain any number of null terminated
2172 strings (variable = value pairs) that will be part of
wdenk7152b1d2003-09-05 23:19:14 +00002173 the default environment compiled into the boot image.
wdenk2262cfe2002-11-18 00:14:45 +00002174
wdenk43d96162003-03-06 00:02:04 +00002175 For example, place something like this in your
2176 board's config file:
wdenkc6097192002-11-03 00:24:07 +00002177
2178 #define CONFIG_EXTRA_ENV_SETTINGS \
2179 "myvar1=value1\0" \
2180 "myvar2=value2\0"
2181
wdenk43d96162003-03-06 00:02:04 +00002182 Warning: This method is based on knowledge about the
2183 internal format how the environment is stored by the
2184 U-Boot code. This is NOT an official, exported
2185 interface! Although it is unlikely that this format
wdenk7152b1d2003-09-05 23:19:14 +00002186 will change soon, there is no guarantee either.
wdenkc6097192002-11-03 00:24:07 +00002187 You better know what you are doing here.
2188
wdenk43d96162003-03-06 00:02:04 +00002189 Note: overly (ab)use of the default environment is
2190 discouraged. Make sure to check other ways to preset
Wolfgang Denk74de7ae2009-04-01 23:34:12 +02002191 the environment like the "source" command or the
wdenk43d96162003-03-06 00:02:04 +00002192 boot command first.
wdenkc6097192002-11-03 00:24:07 +00002193
Simon Glass06fd8532012-11-30 13:01:17 +00002194 CONFIG_DELAY_ENVIRONMENT
2195
2196 Normally the environment is loaded when the board is
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08002197 initialised so that it is available to U-Boot. This inhibits
Simon Glass06fd8532012-11-30 13:01:17 +00002198 that so that the environment is not available until
2199 explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL
2200 this is instead controlled by the value of
2201 /config/load-environment.
2202
Eric Nelsonf61ec452012-01-31 10:52:08 -07002203- Serial Flash support
Simon Glass00fd59d2017-08-04 16:35:06 -06002204 Usage requires an initial 'sf probe' to define the serial
Eric Nelsonf61ec452012-01-31 10:52:08 -07002205 flash parameters, followed by read/write/erase/update
2206 commands.
2207
2208 The following defaults may be provided by the platform
2209 to handle the common case when only a single serial
2210 flash is present on the system.
2211
2212 CONFIG_SF_DEFAULT_BUS Bus identifier
2213 CONFIG_SF_DEFAULT_CS Chip-select
2214 CONFIG_SF_DEFAULT_MODE (see include/spi.h)
2215 CONFIG_SF_DEFAULT_SPEED in Hz
2216
wdenk3f85ce22004-02-23 16:11:30 +00002217
Wolfgang Denkecb0ccd2005-09-24 22:37:32 +02002218- TFTP Fixed UDP Port:
2219 CONFIG_TFTP_PORT
2220
Wolfgang Denk28cb9372005-09-24 23:25:46 +02002221 If this is defined, the environment variable tftpsrcp
Wolfgang Denkecb0ccd2005-09-24 22:37:32 +02002222 is used to supply the TFTP UDP source port value.
Wolfgang Denk28cb9372005-09-24 23:25:46 +02002223 If tftpsrcp isn't defined, the normal pseudo-random port
Wolfgang Denkecb0ccd2005-09-24 22:37:32 +02002224 number generator is used.
2225
Wolfgang Denk28cb9372005-09-24 23:25:46 +02002226 Also, the environment variable tftpdstp is used to supply
2227 the TFTP UDP destination port value. If tftpdstp isn't
2228 defined, the normal port 69 is used.
2229
2230 The purpose for tftpsrcp is to allow a TFTP server to
Wolfgang Denkecb0ccd2005-09-24 22:37:32 +02002231 blindly start the TFTP transfer using the pre-configured
2232 target IP address and UDP port. This has the effect of
2233 "punching through" the (Windows XP) firewall, allowing
2234 the remainder of the TFTP transfer to proceed normally.
2235 A better solution is to properly configure the firewall,
2236 but sometimes that is not allowed.
2237
wdenka8c7c702003-12-06 19:49:23 +00002238- Show boot progress:
wdenkc6097192002-11-03 00:24:07 +00002239 CONFIG_SHOW_BOOT_PROGRESS
2240
wdenk43d96162003-03-06 00:02:04 +00002241 Defining this option allows to add some board-
2242 specific code (calling a user-provided function
2243 "show_boot_progress(int)") that enables you to show
2244 the system's boot progress on some display (for
2245 example, some LED's) on your board. At the moment,
2246 the following checkpoints are implemented:
wdenkc6097192002-11-03 00:24:07 +00002247
Simon Glass94fd1312012-09-28 08:56:37 +00002248
Marian Balakowicz1372cce2008-03-12 10:33:01 +01002249Legacy uImage format:
2250
wdenkc6097192002-11-03 00:24:07 +00002251 Arg Where When
2252 1 common/cmd_bootm.c before attempting to boot an image
wdenkba56f622004-02-06 23:19:44 +00002253 -1 common/cmd_bootm.c Image header has bad magic number
wdenkc6097192002-11-03 00:24:07 +00002254 2 common/cmd_bootm.c Image header has correct magic number
wdenkba56f622004-02-06 23:19:44 +00002255 -2 common/cmd_bootm.c Image header has bad checksum
wdenkc6097192002-11-03 00:24:07 +00002256 3 common/cmd_bootm.c Image header has correct checksum
wdenkba56f622004-02-06 23:19:44 +00002257 -3 common/cmd_bootm.c Image data has bad checksum
wdenkc6097192002-11-03 00:24:07 +00002258 4 common/cmd_bootm.c Image data has correct checksum
2259 -4 common/cmd_bootm.c Image is for unsupported architecture
2260 5 common/cmd_bootm.c Architecture check OK
Marian Balakowicz1372cce2008-03-12 10:33:01 +01002261 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi)
wdenkc6097192002-11-03 00:24:07 +00002262 6 common/cmd_bootm.c Image Type check OK
2263 -6 common/cmd_bootm.c gunzip uncompression error
2264 -7 common/cmd_bootm.c Unimplemented compression type
2265 7 common/cmd_bootm.c Uncompression OK
Marian Balakowicz1372cce2008-03-12 10:33:01 +01002266 8 common/cmd_bootm.c No uncompress/copy overwrite error
wdenkc6097192002-11-03 00:24:07 +00002267 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
Marian Balakowicz1372cce2008-03-12 10:33:01 +01002268
2269 9 common/image.c Start initial ramdisk verification
2270 -10 common/image.c Ramdisk header has bad magic number
2271 -11 common/image.c Ramdisk header has bad checksum
2272 10 common/image.c Ramdisk header is OK
2273 -12 common/image.c Ramdisk data has bad checksum
2274 11 common/image.c Ramdisk data has correct checksum
2275 12 common/image.c Ramdisk verification complete, start loading
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002276 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk)
Marian Balakowicz1372cce2008-03-12 10:33:01 +01002277 13 common/image.c Start multifile image verification
2278 14 common/image.c No initial ramdisk, no multifile, continue.
2279
Wolfgang Denkc0f40852011-10-26 10:21:21 +00002280 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS
wdenkc6097192002-11-03 00:24:07 +00002281
Stefan Roesea47a12b2010-04-15 16:07:28 +02002282 -30 arch/powerpc/lib/board.c Fatal error, hang the system
wdenk11dadd52004-02-27 00:07:27 +00002283 -31 post/post.c POST test failed, detected by post_output_backlog()
2284 -32 post/post.c POST test failed, detected by post_run_single()
wdenk63e73c92004-02-23 22:22:28 +00002285
Heiko Schocher566a4942007-06-22 19:11:54 +02002286 34 common/cmd_doc.c before loading a Image from a DOC device
2287 -35 common/cmd_doc.c Bad usage of "doc" command
2288 35 common/cmd_doc.c correct usage of "doc" command
2289 -36 common/cmd_doc.c No boot device
2290 36 common/cmd_doc.c correct boot device
2291 -37 common/cmd_doc.c Unknown Chip ID on boot device
2292 37 common/cmd_doc.c correct chip ID found, device available
2293 -38 common/cmd_doc.c Read Error on boot device
2294 38 common/cmd_doc.c reading Image header from DOC device OK
2295 -39 common/cmd_doc.c Image header has bad magic number
2296 39 common/cmd_doc.c Image header has correct magic number
2297 -40 common/cmd_doc.c Error reading Image from DOC device
2298 40 common/cmd_doc.c Image header has correct magic number
2299 41 common/cmd_ide.c before loading a Image from a IDE device
2300 -42 common/cmd_ide.c Bad usage of "ide" command
2301 42 common/cmd_ide.c correct usage of "ide" command
2302 -43 common/cmd_ide.c No boot device
2303 43 common/cmd_ide.c boot device found
2304 -44 common/cmd_ide.c Device not available
2305 44 common/cmd_ide.c Device available
2306 -45 common/cmd_ide.c wrong partition selected
2307 45 common/cmd_ide.c partition selected
2308 -46 common/cmd_ide.c Unknown partition table
2309 46 common/cmd_ide.c valid partition table found
2310 -47 common/cmd_ide.c Invalid partition type
2311 47 common/cmd_ide.c correct partition type
2312 -48 common/cmd_ide.c Error reading Image Header on boot device
2313 48 common/cmd_ide.c reading Image Header from IDE device OK
2314 -49 common/cmd_ide.c Image header has bad magic number
2315 49 common/cmd_ide.c Image header has correct magic number
2316 -50 common/cmd_ide.c Image header has bad checksum
2317 50 common/cmd_ide.c Image header has correct checksum
2318 -51 common/cmd_ide.c Error reading Image from IDE device
2319 51 common/cmd_ide.c reading Image from IDE device OK
2320 52 common/cmd_nand.c before loading a Image from a NAND device
2321 -53 common/cmd_nand.c Bad usage of "nand" command
2322 53 common/cmd_nand.c correct usage of "nand" command
2323 -54 common/cmd_nand.c No boot device
2324 54 common/cmd_nand.c boot device found
2325 -55 common/cmd_nand.c Unknown Chip ID on boot device
2326 55 common/cmd_nand.c correct chip ID found, device available
2327 -56 common/cmd_nand.c Error reading Image Header on boot device
2328 56 common/cmd_nand.c reading Image Header from NAND device OK
2329 -57 common/cmd_nand.c Image header has bad magic number
2330 57 common/cmd_nand.c Image header has correct magic number
2331 -58 common/cmd_nand.c Error reading Image from NAND device
2332 58 common/cmd_nand.c reading Image from NAND device OK
wdenkc6097192002-11-03 00:24:07 +00002333
Heiko Schocher566a4942007-06-22 19:11:54 +02002334 -60 common/env_common.c Environment has a bad CRC, using default
wdenkc6097192002-11-03 00:24:07 +00002335
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002336 64 net/eth.c starting with Ethernet configuration.
Heiko Schocher566a4942007-06-22 19:11:54 +02002337 -64 net/eth.c no Ethernet found.
2338 65 net/eth.c Ethernet found.
wdenk206c60c2003-09-18 10:02:25 +00002339
Heiko Schocher566a4942007-06-22 19:11:54 +02002340 -80 common/cmd_net.c usage wrong
Joe Hershbergerbc0571f2015-04-08 01:41:21 -05002341 80 common/cmd_net.c before calling net_loop()
2342 -81 common/cmd_net.c some error in net_loop() occurred
2343 81 common/cmd_net.c net_loop() back without error
Heiko Schocher566a4942007-06-22 19:11:54 +02002344 -82 common/cmd_net.c size == 0 (File with size 0 loaded)
2345 82 common/cmd_net.c trying automatic boot
Wolfgang Denk74de7ae2009-04-01 23:34:12 +02002346 83 common/cmd_net.c running "source" command
2347 -83 common/cmd_net.c some error in automatic boot or "source" command
Heiko Schocher566a4942007-06-22 19:11:54 +02002348 84 common/cmd_net.c end without errors
wdenkc6097192002-11-03 00:24:07 +00002349
Marian Balakowicz1372cce2008-03-12 10:33:01 +01002350FIT uImage format:
2351
2352 Arg Where When
2353 100 common/cmd_bootm.c Kernel FIT Image has correct format
2354 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format
2355 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration
2356 -101 common/cmd_bootm.c Can't get configuration for kernel subimage
2357 102 common/cmd_bootm.c Kernel unit name specified
2358 -103 common/cmd_bootm.c Can't get kernel subimage node offset
Marian Balakowiczf773bea2008-03-12 10:35:46 +01002359 103 common/cmd_bootm.c Found configuration node
Marian Balakowicz1372cce2008-03-12 10:33:01 +01002360 104 common/cmd_bootm.c Got kernel subimage node offset
2361 -104 common/cmd_bootm.c Kernel subimage hash verification failed
2362 105 common/cmd_bootm.c Kernel subimage hash verification OK
2363 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture
2364 106 common/cmd_bootm.c Architecture check OK
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002365 -106 common/cmd_bootm.c Kernel subimage has wrong type
2366 107 common/cmd_bootm.c Kernel subimage type OK
Marian Balakowicz1372cce2008-03-12 10:33:01 +01002367 -107 common/cmd_bootm.c Can't get kernel subimage data/size
2368 108 common/cmd_bootm.c Got kernel subimage data/size
2369 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT)
2370 -109 common/cmd_bootm.c Can't get kernel subimage type
2371 -110 common/cmd_bootm.c Can't get kernel subimage comp
2372 -111 common/cmd_bootm.c Can't get kernel subimage os
2373 -112 common/cmd_bootm.c Can't get kernel subimage load address
2374 -113 common/cmd_bootm.c Image uncompress/copy overwrite error
2375
2376 120 common/image.c Start initial ramdisk verification
2377 -120 common/image.c Ramdisk FIT image has incorrect format
2378 121 common/image.c Ramdisk FIT image has correct format
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002379 122 common/image.c No ramdisk subimage unit name, using configuration
Marian Balakowicz1372cce2008-03-12 10:33:01 +01002380 -122 common/image.c Can't get configuration for ramdisk subimage
2381 123 common/image.c Ramdisk unit name specified
2382 -124 common/image.c Can't get ramdisk subimage node offset
2383 125 common/image.c Got ramdisk subimage node offset
2384 -125 common/image.c Ramdisk subimage hash verification failed
2385 126 common/image.c Ramdisk subimage hash verification OK
2386 -126 common/image.c Ramdisk subimage for unsupported architecture
2387 127 common/image.c Architecture check OK
2388 -127 common/image.c Can't get ramdisk subimage data/size
2389 128 common/image.c Got ramdisk subimage data/size
2390 129 common/image.c Can't get ramdisk load address
2391 -129 common/image.c Got ramdisk load address
2392
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002393 -130 common/cmd_doc.c Incorrect FIT image format
Marian Balakowicz1372cce2008-03-12 10:33:01 +01002394 131 common/cmd_doc.c FIT image format OK
2395
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002396 -140 common/cmd_ide.c Incorrect FIT image format
Marian Balakowicz1372cce2008-03-12 10:33:01 +01002397 141 common/cmd_ide.c FIT image format OK
2398
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002399 -150 common/cmd_nand.c Incorrect FIT image format
Marian Balakowicz1372cce2008-03-12 10:33:01 +01002400 151 common/cmd_nand.c FIT image format OK
2401
Wolfgang Denk4cf26092011-10-07 09:58:21 +02002402- Standalone program support:
2403 CONFIG_STANDALONE_LOAD_ADDR
2404
Wolfgang Denk6feff892011-10-09 21:06:34 +02002405 This option defines a board specific value for the
2406 address where standalone program gets loaded, thus
2407 overwriting the architecture dependent default
Wolfgang Denk4cf26092011-10-07 09:58:21 +02002408 settings.
2409
2410- Frame Buffer Address:
2411 CONFIG_FB_ADDR
2412
2413 Define CONFIG_FB_ADDR if you want to use specific
Wolfgang Denk44a53b52013-01-03 00:43:59 +00002414 address for frame buffer. This is typically the case
2415 when using a graphics controller has separate video
2416 memory. U-Boot will then place the frame buffer at
2417 the given address instead of dynamically reserving it
2418 in system RAM by calling lcd_setmem(), which grabs
2419 the memory for the frame buffer depending on the
2420 configured panel size.
Wolfgang Denk4cf26092011-10-07 09:58:21 +02002421
2422 Please see board_init_f function.
2423
Detlev Zundelcccfc2a2009-12-01 17:16:19 +01002424- Automatic software updates via TFTP server
2425 CONFIG_UPDATE_TFTP
2426 CONFIG_UPDATE_TFTP_CNT_MAX
2427 CONFIG_UPDATE_TFTP_MSEC_MAX
2428
2429 These options enable and control the auto-update feature;
2430 for a more detailed description refer to doc/README.update.
2431
2432- MTD Support (mtdparts command, UBI support)
Heiko Schocherff94bc42014-06-24 10:10:04 +02002433 CONFIG_MTD_UBI_WL_THRESHOLD
2434 This parameter defines the maximum difference between the highest
2435 erase counter value and the lowest erase counter value of eraseblocks
2436 of UBI devices. When this threshold is exceeded, UBI starts performing
2437 wear leveling by means of moving data from eraseblock with low erase
2438 counter to eraseblocks with high erase counter.
2439
2440 The default value should be OK for SLC NAND flashes, NOR flashes and
2441 other flashes which have eraseblock life-cycle 100000 or more.
2442 However, in case of MLC NAND flashes which typically have eraseblock
2443 life-cycle less than 10000, the threshold should be lessened (e.g.,
2444 to 128 or 256, although it does not have to be power of 2).
2445
2446 default: 4096
Simon Glassc654b512014-10-23 18:58:54 -06002447
Heiko Schocherff94bc42014-06-24 10:10:04 +02002448 CONFIG_MTD_UBI_BEB_LIMIT
2449 This option specifies the maximum bad physical eraseblocks UBI
2450 expects on the MTD device (per 1024 eraseblocks). If the
2451 underlying flash does not admit of bad eraseblocks (e.g. NOR
2452 flash), this value is ignored.
2453
2454 NAND datasheets often specify the minimum and maximum NVM
2455 (Number of Valid Blocks) for the flashes' endurance lifetime.
2456 The maximum expected bad eraseblocks per 1024 eraseblocks
2457 then can be calculated as "1024 * (1 - MinNVB / MaxNVB)",
2458 which gives 20 for most NANDs (MaxNVB is basically the total
2459 count of eraseblocks on the chip).
2460
2461 To put it differently, if this value is 20, UBI will try to
2462 reserve about 1.9% of physical eraseblocks for bad blocks
2463 handling. And that will be 1.9% of eraseblocks on the entire
2464 NAND chip, not just the MTD partition UBI attaches. This means
2465 that if you have, say, a NAND flash chip admits maximum 40 bad
2466 eraseblocks, and it is split on two MTD partitions of the same
2467 size, UBI will reserve 40 eraseblocks when attaching a
2468 partition.
2469
2470 default: 20
2471
2472 CONFIG_MTD_UBI_FASTMAP
2473 Fastmap is a mechanism which allows attaching an UBI device
2474 in nearly constant time. Instead of scanning the whole MTD device it
2475 only has to locate a checkpoint (called fastmap) on the device.
2476 The on-flash fastmap contains all information needed to attach
2477 the device. Using fastmap makes only sense on large devices where
2478 attaching by scanning takes long. UBI will not automatically install
2479 a fastmap on old images, but you can set the UBI parameter
2480 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT to 1 if you want so. Please note
2481 that fastmap-enabled images are still usable with UBI implementations
2482 without fastmap support. On typical flash devices the whole fastmap
2483 fits into one PEB. UBI will reserve PEBs to hold two fastmaps.
2484
2485 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT
2486 Set this parameter to enable fastmap automatically on images
2487 without a fastmap.
2488 default: 0
2489
Heiko Schocher0195a7b2015-10-22 06:19:21 +02002490 CONFIG_MTD_UBI_FM_DEBUG
2491 Enable UBI fastmap debug
2492 default: 0
2493
Daniel Schwierzeck6a11cf42011-07-18 07:48:07 +00002494- SPL framework
Wolfgang Denk04e5ae72011-09-11 21:24:09 +02002495 CONFIG_SPL
2496 Enable building of SPL globally.
Daniel Schwierzeck6a11cf42011-07-18 07:48:07 +00002497
Tom Rini95579792012-02-14 07:29:40 +00002498 CONFIG_SPL_LDSCRIPT
2499 LDSCRIPT for linking the SPL binary.
2500
Albert ARIBAUD6ebc3462013-04-12 05:14:30 +00002501 CONFIG_SPL_MAX_FOOTPRINT
2502 Maximum size in memory allocated to the SPL, BSS included.
2503 When defined, the linker checks that the actual memory
2504 used by SPL from _start to __bss_end does not exceed it.
Albert ARIBAUD8960af82013-04-14 04:48:38 +00002505 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
Albert ARIBAUD6ebc3462013-04-12 05:14:30 +00002506 must not be both defined at the same time.
2507
Tom Rini95579792012-02-14 07:29:40 +00002508 CONFIG_SPL_MAX_SIZE
Albert ARIBAUD6ebc3462013-04-12 05:14:30 +00002509 Maximum size of the SPL image (text, data, rodata, and
2510 linker lists sections), BSS excluded.
2511 When defined, the linker checks that the actual size does
2512 not exceed it.
Tom Rini95579792012-02-14 07:29:40 +00002513
Wolfgang Denk04e5ae72011-09-11 21:24:09 +02002514 CONFIG_SPL_TEXT_BASE
2515 TEXT_BASE for linking the SPL binary.
Daniel Schwierzeck6a11cf42011-07-18 07:48:07 +00002516
Scott Wood94a45bb2012-09-20 19:05:12 -05002517 CONFIG_SPL_RELOC_TEXT_BASE
2518 Address to relocate to. If unspecified, this is equal to
2519 CONFIG_SPL_TEXT_BASE (i.e. no relocation is done).
2520
Tom Rini95579792012-02-14 07:29:40 +00002521 CONFIG_SPL_BSS_START_ADDR
2522 Link address for the BSS within the SPL binary.
2523
2524 CONFIG_SPL_BSS_MAX_SIZE
Albert ARIBAUD6ebc3462013-04-12 05:14:30 +00002525 Maximum size in memory allocated to the SPL BSS.
2526 When defined, the linker checks that the actual memory used
2527 by SPL from __bss_start to __bss_end does not exceed it.
Albert ARIBAUD8960af82013-04-14 04:48:38 +00002528 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
Albert ARIBAUD6ebc3462013-04-12 05:14:30 +00002529 must not be both defined at the same time.
Tom Rini95579792012-02-14 07:29:40 +00002530
2531 CONFIG_SPL_STACK
2532 Adress of the start of the stack SPL will use
2533
Albert ARIBAUD \(3ADEV\)8c80eb32015-03-31 11:40:50 +02002534 CONFIG_SPL_PANIC_ON_RAW_IMAGE
2535 When defined, SPL will panic() if the image it has
2536 loaded does not have a signature.
2537 Defining this is useful when code which loads images
2538 in SPL cannot guarantee that absolutely all read errors
2539 will be caught.
2540 An example is the LPC32XX MLC NAND driver, which will
2541 consider that a completely unreadable NAND block is bad,
2542 and thus should be skipped silently.
2543
Scott Wood94a45bb2012-09-20 19:05:12 -05002544 CONFIG_SPL_RELOC_STACK
2545 Adress of the start of the stack SPL will use after
2546 relocation. If unspecified, this is equal to
2547 CONFIG_SPL_STACK.
2548
Tom Rini95579792012-02-14 07:29:40 +00002549 CONFIG_SYS_SPL_MALLOC_START
2550 Starting address of the malloc pool used in SPL.
Fabio Estevam9ac4fc82015-11-12 12:30:19 -02002551 When this option is set the full malloc is used in SPL and
2552 it is set up by spl_init() and before that, the simple malloc()
2553 can be used if CONFIG_SYS_MALLOC_F is defined.
Tom Rini95579792012-02-14 07:29:40 +00002554
2555 CONFIG_SYS_SPL_MALLOC_SIZE
2556 The size of the malloc pool used in SPL.
Daniel Schwierzeck6a11cf42011-07-18 07:48:07 +00002557
Tom Rini9607faf2014-03-28 12:03:39 -04002558 CONFIG_SPL_OS_BOOT
2559 Enable booting directly to an OS from SPL.
2560 See also: doc/README.falcon
2561
Tom Rini861a86f2012-08-13 11:37:56 -07002562 CONFIG_SPL_DISPLAY_PRINT
2563 For ARM, enable an optional function to print more information
2564 about the running system.
2565
Scott Wood4b919722012-09-20 16:35:21 -05002566 CONFIG_SPL_INIT_MINIMAL
2567 Arch init code should be built for a very small image
2568
Paul Kocialkowskib97300b2014-11-08 23:14:56 +01002569 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_PARTITION
2570 Partition on the MMC to load U-Boot from when the MMC is being
2571 used in raw mode
2572
Peter Korsgaard2b75b0a2013-05-13 08:36:29 +00002573 CONFIG_SYS_MMCSD_RAW_MODE_KERNEL_SECTOR
2574 Sector to load kernel uImage from when MMC is being
2575 used in raw mode (for Falcon mode)
2576
2577 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTOR,
2578 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTORS
2579 Sector and number of sectors to load kernel argument
2580 parameters from when MMC is being used in raw mode
2581 (for falcon mode)
2582
Paul Kocialkowskie2ccdf82014-11-08 23:14:55 +01002583 CONFIG_SYS_MMCSD_FS_BOOT_PARTITION
2584 Partition on the MMC to load U-Boot from when the MMC is being
2585 used in fs mode
2586
Guillaume GARDETfae81c72014-10-15 17:53:13 +02002587 CONFIG_SPL_FS_LOAD_PAYLOAD_NAME
2588 Filename to read to load U-Boot when reading from filesystem
2589
2590 CONFIG_SPL_FS_LOAD_KERNEL_NAME
Peter Korsgaard7ad2cc72013-05-13 08:36:27 +00002591 Filename to read to load kernel uImage when reading
Guillaume GARDETfae81c72014-10-15 17:53:13 +02002592 from filesystem (for Falcon mode)
Peter Korsgaard7ad2cc72013-05-13 08:36:27 +00002593
Guillaume GARDETfae81c72014-10-15 17:53:13 +02002594 CONFIG_SPL_FS_LOAD_ARGS_NAME
Peter Korsgaard7ad2cc72013-05-13 08:36:27 +00002595 Filename to read to load kernel argument parameters
Guillaume GARDETfae81c72014-10-15 17:53:13 +02002596 when reading from filesystem (for Falcon mode)
Peter Korsgaard7ad2cc72013-05-13 08:36:27 +00002597
Scott Wood06f60ae2012-12-06 13:33:17 +00002598 CONFIG_SPL_MPC83XX_WAIT_FOR_NAND
2599 Set this for NAND SPL on PPC mpc83xx targets, so that
2600 start.S waits for the rest of the SPL to load before
2601 continuing (the hardware starts execution after just
2602 loading the first page rather than the full 4K).
2603
Prabhakar Kushwaha651fcf62014-04-08 19:12:31 +05302604 CONFIG_SPL_SKIP_RELOCATE
2605 Avoid SPL relocation
2606
Scott Wood6f2f01b2012-09-20 19:09:07 -05002607 CONFIG_SPL_NAND_BASE
2608 Include nand_base.c in the SPL. Requires
2609 CONFIG_SPL_NAND_DRIVERS.
2610
2611 CONFIG_SPL_NAND_DRIVERS
2612 SPL uses normal NAND drivers, not minimal drivers.
2613
Jörg Krause15e207f2018-01-14 19:26:38 +01002614 CONFIG_SPL_NAND_IDENT
2615 SPL uses the chip ID list to identify the NAND flash.
2616 Requires CONFIG_SPL_NAND_BASE.
2617
Scott Wood6f2f01b2012-09-20 19:09:07 -05002618 CONFIG_SPL_NAND_ECC
2619 Include standard software ECC in the SPL
2620
Tom Rini95579792012-02-14 07:29:40 +00002621 CONFIG_SPL_NAND_SIMPLE
Scott Wood7d4b7952012-09-21 18:35:27 -05002622 Support for NAND boot using simple NAND drivers that
2623 expose the cmd_ctrl() interface.
Tom Rini95579792012-02-14 07:29:40 +00002624
Thomas Gleixner6f4e7d32016-07-12 20:28:12 +02002625 CONFIG_SPL_UBI
2626 Support for a lightweight UBI (fastmap) scanner and
2627 loader
2628
Heiko Schocher0c3117b2014-10-31 08:31:00 +01002629 CONFIG_SPL_NAND_RAW_ONLY
2630 Support to boot only raw u-boot.bin images. Use this only
2631 if you need to save space.
2632
Ying Zhang7c8eea52013-08-16 15:16:12 +08002633 CONFIG_SPL_COMMON_INIT_DDR
2634 Set for common ddr init with serial presence detect in
2635 SPL binary.
2636
Tom Rini95579792012-02-14 07:29:40 +00002637 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT,
2638 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE,
2639 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS,
2640 CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE,
2641 CONFIG_SYS_NAND_ECCBYTES
2642 Defines the size and behavior of the NAND that SPL uses
Scott Wood7d4b7952012-09-21 18:35:27 -05002643 to read U-Boot
Tom Rini95579792012-02-14 07:29:40 +00002644
Prabhakar Kushwahafbe76ae2013-12-11 12:42:11 +05302645 CONFIG_SPL_NAND_BOOT
2646 Add support NAND boot
2647
Tom Rini95579792012-02-14 07:29:40 +00002648 CONFIG_SYS_NAND_U_BOOT_OFFS
Scott Wood7d4b7952012-09-21 18:35:27 -05002649 Location in NAND to read U-Boot from
2650
2651 CONFIG_SYS_NAND_U_BOOT_DST
2652 Location in memory to load U-Boot to
2653
2654 CONFIG_SYS_NAND_U_BOOT_SIZE
2655 Size of image to load
Tom Rini95579792012-02-14 07:29:40 +00002656
2657 CONFIG_SYS_NAND_U_BOOT_START
Scott Wood7d4b7952012-09-21 18:35:27 -05002658 Entry point in loaded image to jump to
Tom Rini95579792012-02-14 07:29:40 +00002659
2660 CONFIG_SYS_NAND_HW_ECC_OOBFIRST
2661 Define this if you need to first read the OOB and then the
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08002662 data. This is used, for example, on davinci platforms.
Tom Rini95579792012-02-14 07:29:40 +00002663
Pavel Machekc57b9532012-08-30 22:42:11 +02002664 CONFIG_SPL_RAM_DEVICE
2665 Support for running image already present in ram, in SPL binary
2666
Scott Wood74752ba2012-12-06 13:33:16 +00002667 CONFIG_SPL_PAD_TO
Benoît Thébaudeau6113d3f2013-04-11 09:35:49 +00002668 Image offset to which the SPL should be padded before appending
2669 the SPL payload. By default, this is defined as
2670 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
2671 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
2672 payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
Scott Wood74752ba2012-12-06 13:33:16 +00002673
Scott Woodca2fca22012-09-21 16:27:32 -05002674 CONFIG_SPL_TARGET
2675 Final target image containing SPL and payload. Some SPLs
2676 use an arch-specific makefile fragment instead, for
2677 example if more than one image needs to be produced.
2678
Marek Vasutb527b9c2018-05-13 00:22:52 +02002679 CONFIG_SPL_FIT_PRINT
Simon Glass87ebee32013-05-08 08:05:59 +00002680 Printing information about a FIT image adds quite a bit of
2681 code to SPL. So this is normally disabled in SPL. Use this
2682 option to re-enable it. This will affect the output of the
2683 bootm command when booting a FIT image.
2684
Ying Zhang3aa29de2013-08-16 15:16:15 +08002685- TPL framework
2686 CONFIG_TPL
2687 Enable building of TPL globally.
2688
2689 CONFIG_TPL_PAD_TO
2690 Image offset to which the TPL should be padded before appending
2691 the TPL payload. By default, this is defined as
Wolfgang Denk93e14592013-10-04 17:43:24 +02002692 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
2693 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
2694 payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
Ying Zhang3aa29de2013-08-16 15:16:15 +08002695
wdenka8c7c702003-12-06 19:49:23 +00002696- Interrupt support (PPC):
2697
wdenkd4ca31c2004-01-02 14:00:00 +00002698 There are common interrupt_init() and timer_interrupt()
2699 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002700 for CPU specific initialization. interrupt_init_cpu()
wdenkd4ca31c2004-01-02 14:00:00 +00002701 should set decrementer_count to appropriate value. If
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002702 CPU resets decrementer automatically after interrupt
wdenkd4ca31c2004-01-02 14:00:00 +00002703 (ppc4xx) it should set decrementer_count to zero.
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002704 timer_interrupt() calls timer_interrupt_cpu() for CPU
wdenkd4ca31c2004-01-02 14:00:00 +00002705 specific handling. If board has watchdog / status_led
2706 / other_activity_monitor it works automatically from
2707 general timer_interrupt().
wdenka8c7c702003-12-06 19:49:23 +00002708
wdenkc6097192002-11-03 00:24:07 +00002709
Helmut Raiger9660e442011-10-20 04:19:47 +00002710Board initialization settings:
2711------------------------------
2712
2713During Initialization u-boot calls a number of board specific functions
2714to allow the preparation of board specific prerequisites, e.g. pin setup
2715before drivers are initialized. To enable these callbacks the
2716following configuration macros have to be defined. Currently this is
2717architecture specific, so please check arch/your_architecture/lib/board.c
2718typically in board_init_f() and board_init_r().
2719
2720- CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f()
2721- CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r()
2722- CONFIG_BOARD_LATE_INIT: Call board_late_init()
2723- CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init()
wdenkc6097192002-11-03 00:24:07 +00002724
wdenkc6097192002-11-03 00:24:07 +00002725Configuration Settings:
2726-----------------------
2727
York Sun4d1fd7f2014-02-26 17:03:19 -08002728- CONFIG_SYS_SUPPORT_64BIT_DATA: Defined automatically if compiled as 64-bit.
2729 Optionally it can be defined to support 64-bit memory commands.
2730
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002731- CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
wdenkc6097192002-11-03 00:24:07 +00002732 undefine this when you're short of memory.
2733
Peter Tyser2fb26042009-01-27 18:03:12 -06002734- CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
2735 width of the commands listed in the 'help' command output.
2736
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002737- CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to
wdenkc6097192002-11-03 00:24:07 +00002738 prompt for user input.
2739
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002740- CONFIG_SYS_CBSIZE: Buffer size for input from the Console
wdenkc6097192002-11-03 00:24:07 +00002741
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002742- CONFIG_SYS_PBSIZE: Buffer size for Console output
wdenkc6097192002-11-03 00:24:07 +00002743
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002744- CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands
wdenkc6097192002-11-03 00:24:07 +00002745
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002746- CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to
wdenkc6097192002-11-03 00:24:07 +00002747 the application (usually a Linux kernel) when it is
2748 booted
2749
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002750- CONFIG_SYS_BAUDRATE_TABLE:
wdenkc6097192002-11-03 00:24:07 +00002751 List of legal baudrate settings for this board.
2752
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002753- CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END:
wdenkc6097192002-11-03 00:24:07 +00002754 Begin and End addresses of the area used by the
2755 simple memory test.
2756
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002757- CONFIG_SYS_MEMTEST_SCRATCH:
wdenk5f535fe2003-09-18 09:21:33 +00002758 Scratch address used by the alternate memory test
2759 You only need to set this if address zero isn't writeable
2760
York Sune8149522015-12-04 11:57:07 -08002761- CONFIG_SYS_MEM_RESERVE_SECURE
York Sune61a7532016-06-24 16:46:18 -07002762 Only implemented for ARMv8 for now.
York Sune8149522015-12-04 11:57:07 -08002763 If defined, the size of CONFIG_SYS_MEM_RESERVE_SECURE memory
2764 is substracted from total RAM and won't be reported to OS.
2765 This memory can be used as secure memory. A variable
York Sune61a7532016-06-24 16:46:18 -07002766 gd->arch.secure_ram is used to track the location. In systems
York Sune8149522015-12-04 11:57:07 -08002767 the RAM base is not zero, or RAM is divided into banks,
2768 this variable needs to be recalcuated to get the address.
2769
York Sunaabd7dd2015-12-07 11:05:29 -08002770- CONFIG_SYS_MEM_TOP_HIDE:
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002771 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header,
Stefan Roese14f73ca2008-03-26 10:14:11 +01002772 this specified memory area will get subtracted from the top
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002773 (end) of RAM and won't get "touched" at all by U-Boot. By
Stefan Roese14f73ca2008-03-26 10:14:11 +01002774 fixing up gd->ram_size the Linux kernel should gets passed
2775 the now "corrected" memory size and won't touch it either.
2776 This should work for arch/ppc and arch/powerpc. Only Linux
Stefan Roese5e12e752008-03-28 11:02:53 +01002777 board ports in arch/powerpc with bootwrapper support that
Stefan Roese14f73ca2008-03-26 10:14:11 +01002778 recalculate the memory size from the SDRAM controller setup
Stefan Roese5e12e752008-03-28 11:02:53 +01002779 will have to get fixed in Linux additionally.
Stefan Roese14f73ca2008-03-26 10:14:11 +01002780
2781 This option can be used as a workaround for the 440EPx/GRx
2782 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't
2783 be touched.
2784
2785 WARNING: Please make sure that this value is a multiple of
2786 the Linux page size (normally 4k). If this is not the case,
2787 then the end address of the Linux memory will be located at a
2788 non page size aligned address and this could cause major
2789 problems.
2790
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002791- CONFIG_SYS_LOADS_BAUD_CHANGE:
wdenkc6097192002-11-03 00:24:07 +00002792 Enable temporary baudrate change while serial download
2793
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002794- CONFIG_SYS_SDRAM_BASE:
wdenkc6097192002-11-03 00:24:07 +00002795 Physical start address of SDRAM. _Must_ be 0 here.
2796
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002797- CONFIG_SYS_FLASH_BASE:
wdenkc6097192002-11-03 00:24:07 +00002798 Physical start address of Flash memory.
2799
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002800- CONFIG_SYS_MONITOR_BASE:
wdenkc6097192002-11-03 00:24:07 +00002801 Physical start address of boot monitor code (set by
2802 make config files to be same as the text base address
Wolfgang Denk14d0a022010-10-07 21:51:12 +02002803 (CONFIG_SYS_TEXT_BASE) used when linking) - same as
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002804 CONFIG_SYS_FLASH_BASE when booting from flash.
wdenkc6097192002-11-03 00:24:07 +00002805
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002806- CONFIG_SYS_MONITOR_LEN:
wdenk8bde7f72003-06-27 21:31:46 +00002807 Size of memory reserved for monitor code, used to
2808 determine _at_compile_time_ (!) if the environment is
2809 embedded within the U-Boot image, or in a separate
2810 flash sector.
wdenkc6097192002-11-03 00:24:07 +00002811
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002812- CONFIG_SYS_MALLOC_LEN:
wdenkc6097192002-11-03 00:24:07 +00002813 Size of DRAM reserved for malloc() use.
2814
Simon Glassd59476b2014-07-10 22:23:28 -06002815- CONFIG_SYS_MALLOC_F_LEN
2816 Size of the malloc() pool for use before relocation. If
2817 this is defined, then a very simple malloc() implementation
2818 will become available before relocation. The address is just
2819 below the global data, and the stack is moved down to make
2820 space.
2821
2822 This feature allocates regions with increasing addresses
2823 within the region. calloc() is supported, but realloc()
2824 is not available. free() is supported but does nothing.
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08002825 The memory will be freed (or in fact just forgotten) when
Simon Glassd59476b2014-07-10 22:23:28 -06002826 U-Boot relocates itself.
2827
Simon Glass38687ae2014-11-10 17:16:54 -07002828- CONFIG_SYS_MALLOC_SIMPLE
2829 Provides a simple and small malloc() and calloc() for those
2830 boards which do not use the full malloc in SPL (which is
2831 enabled with CONFIG_SYS_SPL_MALLOC_START).
2832
Thierry Reding1dfdd9b2014-12-09 22:25:22 -07002833- CONFIG_SYS_NONCACHED_MEMORY:
2834 Size of non-cached memory area. This area of memory will be
2835 typically located right below the malloc() area and mapped
2836 uncached in the MMU. This is useful for drivers that would
2837 otherwise require a lot of explicit cache maintenance. For
2838 some drivers it's also impossible to properly maintain the
2839 cache. For example if the regions that need to be flushed
2840 are not a multiple of the cache-line size, *and* padding
2841 cannot be allocated between the regions to align them (i.e.
2842 if the HW requires a contiguous array of regions, and the
2843 size of each region is not cache-aligned), then a flush of
2844 one region may result in overwriting data that hardware has
2845 written to another region in the same cache-line. This can
2846 happen for example in network drivers where descriptors for
2847 buffers are typically smaller than the CPU cache-line (e.g.
2848 16 bytes vs. 32 or 64 bytes).
2849
2850 Non-cached memory is only supported on 32-bit ARM at present.
2851
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002852- CONFIG_SYS_BOOTM_LEN:
Stefan Roese15940c92006-03-13 11:16:36 +01002853 Normally compressed uImages are limited to an
2854 uncompressed size of 8 MBytes. If this is not enough,
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002855 you can define CONFIG_SYS_BOOTM_LEN in your board config file
Stefan Roese15940c92006-03-13 11:16:36 +01002856 to adjust this setting to your needs.
2857
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002858- CONFIG_SYS_BOOTMAPSZ:
wdenkc6097192002-11-03 00:24:07 +00002859 Maximum size of memory mapped by the startup code of
2860 the Linux kernel; all data that must be processed by
Bartlomiej Sieka7d721e32008-04-14 15:44:16 +02002861 the Linux kernel (bd_info, boot arguments, FDT blob if
2862 used) must be put below this limit, unless "bootm_low"
Robert P. J. Day1bce2ae2013-09-16 07:15:45 -04002863 environment variable is defined and non-zero. In such case
Bartlomiej Sieka7d721e32008-04-14 15:44:16 +02002864 all data for the Linux kernel must be between "bootm_low"
Wolfgang Denkc0f40852011-10-26 10:21:21 +00002865 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment
Grant Likelyc3624e62011-03-28 09:58:43 +00002866 variable "bootm_mapsize" will override the value of
2867 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined,
2868 then the value in "bootm_size" will be used instead.
wdenkc6097192002-11-03 00:24:07 +00002869
John Rigbyfca43cc2010-10-13 13:57:35 -06002870- CONFIG_SYS_BOOT_RAMDISK_HIGH:
2871 Enable initrd_high functionality. If defined then the
2872 initrd_high feature is enabled and the bootm ramdisk subcommand
2873 is enabled.
2874
2875- CONFIG_SYS_BOOT_GET_CMDLINE:
2876 Enables allocating and saving kernel cmdline in space between
2877 "bootm_low" and "bootm_low" + BOOTMAPSZ.
2878
2879- CONFIG_SYS_BOOT_GET_KBD:
2880 Enables allocating and saving a kernel copy of the bd_info in
2881 space between "bootm_low" and "bootm_low" + BOOTMAPSZ.
2882
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002883- CONFIG_SYS_MAX_FLASH_BANKS:
wdenkc6097192002-11-03 00:24:07 +00002884 Max number of Flash memory banks
2885
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002886- CONFIG_SYS_MAX_FLASH_SECT:
wdenkc6097192002-11-03 00:24:07 +00002887 Max number of sectors on a Flash chip
2888
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002889- CONFIG_SYS_FLASH_ERASE_TOUT:
wdenkc6097192002-11-03 00:24:07 +00002890 Timeout for Flash erase operations (in ms)
2891
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002892- CONFIG_SYS_FLASH_WRITE_TOUT:
wdenkc6097192002-11-03 00:24:07 +00002893 Timeout for Flash write operations (in ms)
2894
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002895- CONFIG_SYS_FLASH_LOCK_TOUT
wdenk8564acf2003-07-14 22:13:32 +00002896 Timeout for Flash set sector lock bit operation (in ms)
2897
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002898- CONFIG_SYS_FLASH_UNLOCK_TOUT
wdenk8564acf2003-07-14 22:13:32 +00002899 Timeout for Flash clear lock bits operation (in ms)
2900
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002901- CONFIG_SYS_FLASH_PROTECTION
wdenk8564acf2003-07-14 22:13:32 +00002902 If defined, hardware flash sectors protection is used
2903 instead of U-Boot software protection.
2904
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002905- CONFIG_SYS_DIRECT_FLASH_TFTP:
wdenkc6097192002-11-03 00:24:07 +00002906
2907 Enable TFTP transfers directly to flash memory;
2908 without this option such a download has to be
2909 performed in two steps: (1) download to RAM, and (2)
2910 copy from RAM to flash.
2911
2912 The two-step approach is usually more reliable, since
2913 you can check if the download worked before you erase
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002914 the flash, but in some situations (when system RAM is
2915 too limited to allow for a temporary copy of the
wdenkc6097192002-11-03 00:24:07 +00002916 downloaded image) this option may be very useful.
2917
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002918- CONFIG_SYS_FLASH_CFI:
wdenk43d96162003-03-06 00:02:04 +00002919 Define if the flash driver uses extra elements in the
wdenk5653fc32004-02-08 22:55:38 +00002920 common flash structure for storing flash geometry.
2921
Jean-Christophe PLAGNIOL-VILLARD00b18832008-08-13 01:40:42 +02002922- CONFIG_FLASH_CFI_DRIVER
wdenk5653fc32004-02-08 22:55:38 +00002923 This option also enables the building of the cfi_flash driver
2924 in the drivers directory
wdenkc6097192002-11-03 00:24:07 +00002925
Piotr Ziecik91809ed2008-11-17 15:57:58 +01002926- CONFIG_FLASH_CFI_MTD
2927 This option enables the building of the cfi_mtd driver
2928 in the drivers directory. The driver exports CFI flash
2929 to the MTD layer.
2930
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002931- CONFIG_SYS_FLASH_USE_BUFFER_WRITE
Guennadi Liakhovetski96ef8312008-04-03 13:36:02 +02002932 Use buffered writes to flash.
2933
2934- CONFIG_FLASH_SPANSION_S29WS_N
2935 s29ws-n MirrorBit flash has non-standard addresses for buffered
2936 write commands.
2937
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002938- CONFIG_SYS_FLASH_QUIET_TEST
Stefan Roese5568e612005-11-22 13:20:42 +01002939 If this option is defined, the common CFI flash doesn't
2940 print it's warning upon not recognized FLASH banks. This
2941 is useful, if some of the configured banks are only
2942 optionally available.
2943
Jerry Van Baren9a042e92008-03-08 13:48:01 -05002944- CONFIG_FLASH_SHOW_PROGRESS
2945 If defined (must be an integer), print out countdown
2946 digits and dots. Recommended value: 45 (9..1) for 80
2947 column displays, 15 (3..1) for 40 column displays.
2948
Stefan Roese352ef3f2013-04-04 15:53:14 +02002949- CONFIG_FLASH_VERIFY
2950 If defined, the content of the flash (destination) is compared
2951 against the source after the write operation. An error message
2952 will be printed when the contents are not identical.
2953 Please note that this option is useless in nearly all cases,
2954 since such flash programming errors usually are detected earlier
2955 while unprotecting/erasing/programming. Please only enable
2956 this option if you really know what you are doing.
2957
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002958- CONFIG_SYS_RX_ETH_BUFFER:
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002959 Defines the number of Ethernet receive buffers. On some
2960 Ethernet controllers it is recommended to set this value
stroese53cf9432003-06-05 15:39:44 +00002961 to 8 or even higher (EEPRO100 or 405 EMAC), since all
2962 buffers can be full shortly after enabling the interface
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002963 on high Ethernet traffic.
stroese53cf9432003-06-05 15:39:44 +00002964 Defaults to 4 if not defined.
2965
Wolfgang Denkea882ba2010-06-20 23:33:59 +02002966- CONFIG_ENV_MAX_ENTRIES
2967
Wolfgang Denk071bc922010-10-27 22:48:30 +02002968 Maximum number of entries in the hash table that is used
2969 internally to store the environment settings. The default
2970 setting is supposed to be generous and should work in most
2971 cases. This setting can be used to tune behaviour; see
2972 lib/hashtable.c for details.
Wolfgang Denkea882ba2010-06-20 23:33:59 +02002973
Joe Hershberger25980902012-12-11 22:16:31 -06002974- CONFIG_ENV_FLAGS_LIST_DEFAULT
2975- CONFIG_ENV_FLAGS_LIST_STATIC
Robert P. J. Day1bce2ae2013-09-16 07:15:45 -04002976 Enable validation of the values given to environment variables when
Joe Hershberger25980902012-12-11 22:16:31 -06002977 calling env set. Variables can be restricted to only decimal,
2978 hexadecimal, or boolean. If CONFIG_CMD_NET is also defined,
2979 the variables can also be restricted to IP address or MAC address.
2980
2981 The format of the list is:
2982 type_attribute = [s|d|x|b|i|m]
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08002983 access_attribute = [a|r|o|c]
2984 attributes = type_attribute[access_attribute]
Joe Hershberger25980902012-12-11 22:16:31 -06002985 entry = variable_name[:attributes]
2986 list = entry[,list]
2987
2988 The type attributes are:
2989 s - String (default)
2990 d - Decimal
2991 x - Hexadecimal
2992 b - Boolean ([1yYtT|0nNfF])
2993 i - IP address
2994 m - MAC address
2995
Joe Hershberger267541f2012-12-11 22:16:34 -06002996 The access attributes are:
2997 a - Any (default)
2998 r - Read-only
2999 o - Write-once
3000 c - Change-default
3001
Joe Hershberger25980902012-12-11 22:16:31 -06003002 - CONFIG_ENV_FLAGS_LIST_DEFAULT
3003 Define this to a list (string) to define the ".flags"
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08003004 environment variable in the default or embedded environment.
Joe Hershberger25980902012-12-11 22:16:31 -06003005
3006 - CONFIG_ENV_FLAGS_LIST_STATIC
3007 Define this to a list (string) to define validation that
3008 should be done if an entry is not found in the ".flags"
3009 environment variable. To override a setting in the static
3010 list, simply add an entry for the same variable name to the
3011 ".flags" variable.
3012
Joe Hershbergerbdf1fe42015-05-20 14:27:20 -05003013 If CONFIG_REGEX is defined, the variable_name above is evaluated as a
3014 regular expression. This allows multiple variables to define the same
3015 flags without explicitly listing them for each variable.
3016
Joe Hershberger267541f2012-12-11 22:16:34 -06003017- CONFIG_ENV_ACCESS_IGNORE_FORCE
3018 If defined, don't allow the -f switch to env set override variable
3019 access flags.
3020
Gabe Black0d296cc2014-10-15 04:38:30 -06003021- CONFIG_USE_STDINT
3022 If stdint.h is available with your toolchain you can define this
3023 option to enable it. You can provide option 'USE_STDINT=1' when
3024 building U-Boot to enable this.
3025
wdenkc6097192002-11-03 00:24:07 +00003026The following definitions that deal with the placement and management
3027of environment data (variable area); in general, we support the
3028following configurations:
3029
Mike Frysingerc3eb3fe2011-07-08 10:44:25 +00003030- CONFIG_BUILD_ENVCRC:
3031
3032 Builds up envcrc with the target environment so that external utils
3033 may easily extract it and embed it in final U-Boot images.
3034
wdenkc6097192002-11-03 00:24:07 +00003035BE CAREFUL! The first access to the environment happens quite early
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08003036in U-Boot initialization (when we try to get the setting of for the
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02003037console baudrate). You *MUST* have mapped your NVRAM area then, or
wdenkc6097192002-11-03 00:24:07 +00003038U-Boot will hang.
3039
3040Please note that even with NVRAM we still use a copy of the
3041environment in RAM: we could work on NVRAM directly, but we want to
3042keep settings there always unmodified except somebody uses "saveenv"
3043to save the current settings.
3044
Liu Gang0a85a9e2012-03-08 00:33:20 +00003045BE CAREFUL! For some special cases, the local device can not use
3046"saveenv" command. For example, the local device will get the
Liu Gangfc54c7f2012-08-09 05:10:01 +00003047environment stored in a remote NOR flash by SRIO or PCIE link,
3048but it can not erase, write this NOR flash by SRIO or PCIE interface.
Liu Gang0a85a9e2012-03-08 00:33:20 +00003049
Guennadi Liakhovetskib74ab732009-05-18 16:07:22 +02003050- CONFIG_NAND_ENV_DST
3051
3052 Defines address in RAM to which the nand_spl code should copy the
3053 environment. If redundant environment is used, it will be copied to
3054 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE.
3055
Bruce Adlere881cb52007-11-02 13:15:42 -07003056Please note that the environment is read-only until the monitor
wdenkc6097192002-11-03 00:24:07 +00003057has been relocated to RAM and a RAM copy of the environment has been
Simon Glass00caae62017-08-03 12:22:12 -06003058created; also, when using EEPROM you will have to use env_get_f()
wdenkc6097192002-11-03 00:24:07 +00003059until then to read environment variables.
3060
wdenk85ec0bc2003-03-31 16:34:49 +00003061The environment is protected by a CRC32 checksum. Before the monitor
3062is relocated into RAM, as a result of a bad CRC you will be working
3063with the compiled-in default environment - *silently*!!! [This is
3064necessary, because the first environment variable we need is the
3065"baudrate" setting for the console - if we have a bad CRC, we don't
3066have any device yet where we could complain.]
wdenkc6097192002-11-03 00:24:07 +00003067
3068Note: once the monitor has been relocated, then it will complain if
3069the default environment is used; a new CRC is computed as soon as you
wdenk85ec0bc2003-03-31 16:34:49 +00003070use the "saveenv" command to store a valid environment.
wdenkc6097192002-11-03 00:24:07 +00003071
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003072- CONFIG_SYS_FAULT_ECHO_LINK_DOWN:
wdenk42d1f032003-10-15 23:53:47 +00003073 Echo the inverted Ethernet link state to the fault LED.
wdenkfc3e2162003-10-08 22:33:00 +00003074
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003075 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR
wdenkfc3e2162003-10-08 22:33:00 +00003076 also needs to be defined.
3077
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003078- CONFIG_SYS_FAULT_MII_ADDR:
wdenk42d1f032003-10-15 23:53:47 +00003079 MII address of the PHY to check for the Ethernet link state.
wdenkc6097192002-11-03 00:24:07 +00003080
Ron Madridf5675aa2009-02-18 14:30:44 -08003081- CONFIG_NS16550_MIN_FUNCTIONS:
3082 Define this if you desire to only have use of the NS16550_init
3083 and NS16550_putc functions for the serial driver located at
3084 drivers/serial/ns16550.c. This option is useful for saving
3085 space for already greatly restricted images, including but not
3086 limited to NAND_SPL configurations.
3087
Simon Glassb2b92f52012-11-30 13:01:18 +00003088- CONFIG_DISPLAY_BOARDINFO
3089 Display information about the board that U-Boot is running on
3090 when U-Boot starts up. The board function checkboard() is called
3091 to do this.
3092
Simon Glasse2e3e2b2012-11-30 13:01:19 +00003093- CONFIG_DISPLAY_BOARDINFO_LATE
3094 Similar to the previous option, but display this information
3095 later, once stdio is running and output goes to the LCD, if
3096 present.
3097
Sascha Silbefeb85802013-08-11 16:40:43 +02003098- CONFIG_BOARD_SIZE_LIMIT:
3099 Maximum size of the U-Boot image. When defined, the
3100 build system checks that the actual size does not
3101 exceed it.
3102
wdenkc6097192002-11-03 00:24:07 +00003103Low Level (hardware related) configuration options:
wdenkdc7c9a12003-03-26 06:55:25 +00003104---------------------------------------------------
wdenkc6097192002-11-03 00:24:07 +00003105
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003106- CONFIG_SYS_CACHELINE_SIZE:
wdenkc6097192002-11-03 00:24:07 +00003107 Cache Line Size of the CPU.
3108
Timur Tabie46fedf2011-08-04 18:03:41 -05003109- CONFIG_SYS_CCSRBAR_DEFAULT:
3110 Default (power-on reset) physical address of CCSR on Freescale
3111 PowerPC SOCs.
3112
3113- CONFIG_SYS_CCSRBAR:
3114 Virtual address of CCSR. On a 32-bit build, this is typically
3115 the same value as CONFIG_SYS_CCSRBAR_DEFAULT.
3116
Timur Tabie46fedf2011-08-04 18:03:41 -05003117- CONFIG_SYS_CCSRBAR_PHYS:
3118 Physical address of CCSR. CCSR can be relocated to a new
3119 physical address, if desired. In this case, this macro should
Wolfgang Denkc0f40852011-10-26 10:21:21 +00003120 be set to that address. Otherwise, it should be set to the
Timur Tabie46fedf2011-08-04 18:03:41 -05003121 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR
3122 is typically relocated on 36-bit builds. It is recommended
3123 that this macro be defined via the _HIGH and _LOW macros:
3124
3125 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH
3126 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW)
3127
3128- CONFIG_SYS_CCSRBAR_PHYS_HIGH:
Wolfgang Denk4cf26092011-10-07 09:58:21 +02003129 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically
3130 either 0 (32-bit build) or 0xF (36-bit build). This macro is
Timur Tabie46fedf2011-08-04 18:03:41 -05003131 used in assembly code, so it must not contain typecasts or
3132 integer size suffixes (e.g. "ULL").
3133
3134- CONFIG_SYS_CCSRBAR_PHYS_LOW:
3135 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is
3136 used in assembly code, so it must not contain typecasts or
3137 integer size suffixes (e.g. "ULL").
3138
3139- CONFIG_SYS_CCSR_DO_NOT_RELOCATE:
3140 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be
3141 forced to a value that ensures that CCSR is not relocated.
3142
wdenk7f6c2cb2002-11-10 22:06:23 +00003143- Floppy Disk Support:
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003144 CONFIG_SYS_FDC_DRIVE_NUMBER
wdenk7f6c2cb2002-11-10 22:06:23 +00003145
3146 the default drive number (default value 0)
3147
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003148 CONFIG_SYS_ISA_IO_STRIDE
wdenk7f6c2cb2002-11-10 22:06:23 +00003149
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02003150 defines the spacing between FDC chipset registers
wdenk7f6c2cb2002-11-10 22:06:23 +00003151 (default value 1)
3152
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003153 CONFIG_SYS_ISA_IO_OFFSET
wdenk7f6c2cb2002-11-10 22:06:23 +00003154
wdenk43d96162003-03-06 00:02:04 +00003155 defines the offset of register from address. It
3156 depends on which part of the data bus is connected to
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02003157 the FDC chipset. (default value 0)
wdenk7f6c2cb2002-11-10 22:06:23 +00003158
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003159 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and
3160 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their
wdenk43d96162003-03-06 00:02:04 +00003161 default value.
wdenk7f6c2cb2002-11-10 22:06:23 +00003162
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003163 if CONFIG_SYS_FDC_HW_INIT is defined, then the function
wdenk43d96162003-03-06 00:02:04 +00003164 fdc_hw_init() is called at the beginning of the FDC
3165 setup. fdc_hw_init() must be provided by the board
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08003166 source code. It is used to make hardware-dependent
wdenk43d96162003-03-06 00:02:04 +00003167 initializations.
wdenk7f6c2cb2002-11-10 22:06:23 +00003168
Macpaul Lin0abddf82011-04-11 20:45:32 +00003169- CONFIG_IDE_AHB:
3170 Most IDE controllers were designed to be connected with PCI
3171 interface. Only few of them were designed for AHB interface.
3172 When software is doing ATA command and data transfer to
3173 IDE devices through IDE-AHB controller, some additional
3174 registers accessing to these kind of IDE-AHB controller
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08003175 is required.
Macpaul Lin0abddf82011-04-11 20:45:32 +00003176
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003177- CONFIG_SYS_IMMR: Physical address of the Internal Memory.
wdenkefe2a4d2004-12-16 21:44:03 +00003178 DO NOT CHANGE unless you know exactly what you're
Christophe Leroy907208c2017-07-06 10:23:22 +02003179 doing! (11-4) [MPC8xx systems only]
wdenkc6097192002-11-03 00:24:07 +00003180
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003181- CONFIG_SYS_INIT_RAM_ADDR:
wdenkc6097192002-11-03 00:24:07 +00003182
wdenk7152b1d2003-09-05 23:19:14 +00003183 Start address of memory area that can be used for
wdenkc6097192002-11-03 00:24:07 +00003184 initial data and stack; please note that this must be
3185 writable memory that is working WITHOUT special
3186 initialization, i. e. you CANNOT use normal RAM which
3187 will become available only after programming the
3188 memory controller and running certain initialization
3189 sequences.
3190
3191 U-Boot uses the following memory types:
Christophe Leroy907208c2017-07-06 10:23:22 +02003192 - MPC8xx: IMMR (internal memory of the CPU)
wdenkc6097192002-11-03 00:24:07 +00003193
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003194- CONFIG_SYS_GBL_DATA_OFFSET:
wdenkc6097192002-11-03 00:24:07 +00003195
3196 Offset of the initial data structure in the memory
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003197 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually
3198 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial
wdenkc6097192002-11-03 00:24:07 +00003199 data is located at the end of the available space
Wolfgang Denk553f0982010-10-26 13:32:32 +02003200 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE -
Simon Glassacd51f92016-10-02 18:01:06 -06003201 GENERATED_GBL_DATA_SIZE), and the initial stack is just
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003202 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR +
3203 CONFIG_SYS_GBL_DATA_OFFSET) downward.
wdenkc6097192002-11-03 00:24:07 +00003204
3205 Note:
3206 On the MPC824X (or other systems that use the data
3207 cache for initial memory) the address chosen for
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003208 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must
wdenkc6097192002-11-03 00:24:07 +00003209 point to an otherwise UNUSED address space between
3210 the top of RAM and the start of the PCI space.
3211
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003212- CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27)
wdenkc6097192002-11-03 00:24:07 +00003213
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003214- CONFIG_SYS_OR_TIMING_SDRAM:
wdenkc6097192002-11-03 00:24:07 +00003215 SDRAM timing
3216
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003217- CONFIG_SYS_MAMR_PTA:
wdenkc6097192002-11-03 00:24:07 +00003218 periodic timer for refresh
3219
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003220- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM,
3221 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP,
3222 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM,
3223 CONFIG_SYS_BR1_PRELIM:
wdenkc6097192002-11-03 00:24:07 +00003224 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
3225
3226- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003227 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM,
3228 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM:
wdenkc6097192002-11-03 00:24:07 +00003229 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
3230
Andrew Sharp69fd2d32012-08-29 14:16:32 +00003231- CONFIG_PCI_ENUM_ONLY
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08003232 Only scan through and get the devices on the buses.
Andrew Sharp69fd2d32012-08-29 14:16:32 +00003233 Don't do any setup work, presumably because someone or
3234 something has already done it, and we don't need to do it
3235 a second time. Useful for platforms that are pre-booted
3236 by coreboot or similar.
3237
Gabor Juhos842033e2013-05-30 07:06:12 +00003238- CONFIG_PCI_INDIRECT_BRIDGE:
3239 Enable support for indirect PCI bridges.
3240
Kumar Galaa09b9b62010-12-30 12:09:53 -06003241- CONFIG_SYS_SRIO:
3242 Chip has SRIO or not
3243
3244- CONFIG_SRIO1:
3245 Board has SRIO 1 port available
3246
3247- CONFIG_SRIO2:
3248 Board has SRIO 2 port available
3249
Liu Gangc8b28152013-05-07 16:30:46 +08003250- CONFIG_SRIO_PCIE_BOOT_MASTER
3251 Board can support master function for Boot from SRIO and PCIE
3252
Kumar Galaa09b9b62010-12-30 12:09:53 -06003253- CONFIG_SYS_SRIOn_MEM_VIRT:
3254 Virtual Address of SRIO port 'n' memory region
3255
3256- CONFIG_SYS_SRIOn_MEM_PHYS:
3257 Physical Address of SRIO port 'n' memory region
3258
3259- CONFIG_SYS_SRIOn_MEM_SIZE:
3260 Size of SRIO port 'n' memory region
3261
Fabio Estevam66bd1842013-04-11 09:35:34 +00003262- CONFIG_SYS_NAND_BUSWIDTH_16BIT
3263 Defined to tell the NAND controller that the NAND chip is using
3264 a 16 bit bus.
3265 Not all NAND drivers use this symbol.
Fabio Estevama430e912013-04-11 09:35:35 +00003266 Example of drivers that use it:
Fabio Estevam66bd1842013-04-11 09:35:34 +00003267 - drivers/mtd/nand/ndfc.c
Fabio Estevama430e912013-04-11 09:35:35 +00003268 - drivers/mtd/nand/mxc_nand.c
Alex Watermaneced4622011-05-19 15:08:36 -04003269
3270- CONFIG_SYS_NDFC_EBC0_CFG
3271 Sets the EBC0_CFG register for the NDFC. If not defined
3272 a default value will be used.
3273
Ben Warrenbb99ad62006-09-07 16:50:54 -04003274- CONFIG_SPD_EEPROM
Wolfgang Denk218ca722008-03-26 10:40:12 +01003275 Get DDR timing information from an I2C EEPROM. Common
3276 with pluggable memory modules such as SODIMMs
3277
Ben Warrenbb99ad62006-09-07 16:50:54 -04003278 SPD_EEPROM_ADDRESS
3279 I2C address of the SPD EEPROM
3280
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003281- CONFIG_SYS_SPD_BUS_NUM
Wolfgang Denk218ca722008-03-26 10:40:12 +01003282 If SPD EEPROM is on an I2C bus other than the first
3283 one, specify here. Note that the value must resolve
3284 to something your driver can deal with.
Ben Warrenbb99ad62006-09-07 16:50:54 -04003285
York Sun1b3e3c42011-06-07 09:42:16 +08003286- CONFIG_SYS_DDR_RAW_TIMING
3287 Get DDR timing information from other than SPD. Common with
3288 soldered DDR chips onboard without SPD. DDR raw timing
3289 parameters are extracted from datasheet and hard-coded into
3290 header files or board specific files.
3291
York Sun6f5e1dc2011-09-16 13:21:35 -07003292- CONFIG_FSL_DDR_INTERACTIVE
3293 Enable interactive DDR debugging. See doc/README.fsl-ddr.
3294
York Sune32d59a2015-01-06 13:18:55 -08003295- CONFIG_FSL_DDR_SYNC_REFRESH
3296 Enable sync of refresh for multiple controllers.
3297
York Sun4516ff82015-03-19 09:30:28 -07003298- CONFIG_FSL_DDR_BIST
3299 Enable built-in memory test for Freescale DDR controllers.
3300
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003301- CONFIG_SYS_83XX_DDR_USES_CS0
Wolfgang Denk218ca722008-03-26 10:40:12 +01003302 Only for 83xx systems. If specified, then DDR should
3303 be configured using CS0 and CS1 instead of CS2 and CS3.
Timur Tabi2ad6b512006-10-31 18:44:42 -06003304
wdenkc26e4542004-04-18 10:13:26 +00003305- CONFIG_RMII
3306 Enable RMII mode for all FECs.
3307 Note that this is a global option, we can't
3308 have one FEC in standard MII mode and another in RMII mode.
3309
wdenk5cf91d62004-04-23 20:32:05 +00003310- CONFIG_CRC32_VERIFY
3311 Add a verify option to the crc32 command.
3312 The syntax is:
3313
3314 => crc32 -v <address> <count> <crc32>
3315
3316 Where address/count indicate a memory area
3317 and crc32 is the correct crc32 which the
3318 area should have.
3319
wdenk56523f12004-07-11 17:40:54 +00003320- CONFIG_LOOPW
3321 Add the "loopw" memory command. This only takes effect if
Simon Glass493f4202017-08-04 16:34:27 -06003322 the memory commands are activated globally (CONFIG_CMD_MEMORY).
wdenk56523f12004-07-11 17:40:54 +00003323
stroese7b466642004-12-16 18:46:55 +00003324- CONFIG_MX_CYCLIC
3325 Add the "mdc" and "mwc" memory commands. These are cyclic
3326 "md/mw" commands.
3327 Examples:
3328
wdenkefe2a4d2004-12-16 21:44:03 +00003329 => mdc.b 10 4 500
stroese7b466642004-12-16 18:46:55 +00003330 This command will print 4 bytes (10,11,12,13) each 500 ms.
3331
wdenkefe2a4d2004-12-16 21:44:03 +00003332 => mwc.l 100 12345678 10
stroese7b466642004-12-16 18:46:55 +00003333 This command will write 12345678 to address 100 all 10 ms.
3334
wdenkefe2a4d2004-12-16 21:44:03 +00003335 This only takes effect if the memory commands are activated
Simon Glass493f4202017-08-04 16:34:27 -06003336 globally (CONFIG_CMD_MEMORY).
stroese7b466642004-12-16 18:46:55 +00003337
wdenk8aa1a2d2005-04-04 12:44:11 +00003338- CONFIG_SKIP_LOWLEVEL_INIT
Rick Chen3fafced2017-12-26 13:55:59 +08003339 [ARM, NDS32, MIPS, RISC-V only] If this variable is defined, then certain
Wolfgang Denk844f07d2010-11-27 23:30:56 +01003340 low level initializations (like setting up the memory
3341 controller) are omitted and/or U-Boot does not
3342 relocate itself into RAM.
wdenk8aa1a2d2005-04-04 12:44:11 +00003343
Wolfgang Denk844f07d2010-11-27 23:30:56 +01003344 Normally this variable MUST NOT be defined. The only
3345 exception is when U-Boot is loaded (to RAM) by some
3346 other boot loader or by a debugger which performs
3347 these initializations itself.
wdenk8aa1a2d2005-04-04 12:44:11 +00003348
Simon Glassb5bd0982016-05-05 07:28:06 -06003349- CONFIG_SKIP_LOWLEVEL_INIT_ONLY
3350 [ARM926EJ-S only] This allows just the call to lowlevel_init()
yeongjun Kim90211f72016-07-20 22:56:12 +09003351 to be skipped. The normal CP15 init (such as enabling the
Simon Glassb5bd0982016-05-05 07:28:06 -06003352 instruction cache) is still performed.
3353
Aneesh V401bb302011-07-13 05:11:07 +00003354- CONFIG_SPL_BUILD
Magnus Liljadf812382009-06-13 20:50:00 +02003355 Modifies the behaviour of start.S when compiling a loader
3356 that is executed before the actual U-Boot. E.g. when
3357 compiling a NAND SPL.
wdenk400558b2005-04-02 23:52:25 +00003358
Ying Zhang3aa29de2013-08-16 15:16:15 +08003359- CONFIG_TPL_BUILD
3360 Modifies the behaviour of start.S when compiling a loader
3361 that is executed after the SPL and before the actual U-Boot.
3362 It is loaded by the SPL.
3363
Ying Zhang5df572f2013-05-20 14:07:23 +08003364- CONFIG_SYS_MPC85XX_NO_RESETVEC
3365 Only for 85xx systems. If this variable is specified, the section
3366 .resetvec is not kept and the section .bootpg is placed in the
3367 previous 4k of the .text section.
3368
Simon Glass4213fc22013-02-24 17:33:14 +00003369- CONFIG_ARCH_MAP_SYSMEM
3370 Generally U-Boot (and in particular the md command) uses
3371 effective address. It is therefore not necessary to regard
3372 U-Boot address as virtual addresses that need to be translated
3373 to physical addresses. However, sandbox requires this, since
3374 it maintains its own little RAM buffer which contains all
3375 addressable memory. This option causes some memory accesses
3376 to be mapped through map_sysmem() / unmap_sysmem().
3377
Simon Glass588a13f2013-02-14 04:18:54 +00003378- CONFIG_X86_RESET_VECTOR
3379 If defined, the x86 reset vector code is included. This is not
3380 needed when U-Boot is running from Coreboot.
Gabe Blackb16f5212012-11-27 21:08:06 +00003381
Karicheri, Muralidharan999d7d32014-04-04 13:16:50 -04003382- CONFIG_SYS_NAND_NO_SUBPAGE_WRITE
3383 Option to disable subpage write in NAND driver
3384 driver that uses this:
3385 drivers/mtd/nand/davinci_nand.c
3386
Timur Tabif2717b42011-11-22 09:21:25 -06003387Freescale QE/FMAN Firmware Support:
3388-----------------------------------
3389
3390The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the
3391loading of "firmware", which is encoded in the QE firmware binary format.
3392This firmware often needs to be loaded during U-Boot booting, so macros
3393are used to identify the storage device (NOR flash, SPI, etc) and the address
3394within that device.
3395
Zhao Qiangdcf1d772014-03-21 16:21:44 +08003396- CONFIG_SYS_FMAN_FW_ADDR
3397 The address in the storage device where the FMAN microcode is located. The
3398 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro
3399 is also specified.
3400
3401- CONFIG_SYS_QE_FW_ADDR
3402 The address in the storage device where the QE microcode is located. The
Timur Tabif2717b42011-11-22 09:21:25 -06003403 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro
3404 is also specified.
3405
3406- CONFIG_SYS_QE_FMAN_FW_LENGTH
3407 The maximum possible size of the firmware. The firmware binary format
3408 has a field that specifies the actual size of the firmware, but it
3409 might not be possible to read any part of the firmware unless some
3410 local storage is allocated to hold the entire firmware first.
3411
3412- CONFIG_SYS_QE_FMAN_FW_IN_NOR
3413 Specifies that QE/FMAN firmware is located in NOR flash, mapped as
3414 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the
3415 virtual address in NOR flash.
3416
3417- CONFIG_SYS_QE_FMAN_FW_IN_NAND
3418 Specifies that QE/FMAN firmware is located in NAND flash.
3419 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash.
3420
3421- CONFIG_SYS_QE_FMAN_FW_IN_MMC
3422 Specifies that QE/FMAN firmware is located on the primary SD/MMC
3423 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
3424
Liu Gang292dc6c2012-03-08 00:33:18 +00003425- CONFIG_SYS_QE_FMAN_FW_IN_REMOTE
3426 Specifies that QE/FMAN firmware is located in the remote (master)
3427 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which
Liu Gangfc54c7f2012-08-09 05:10:01 +00003428 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound
3429 window->master inbound window->master LAW->the ucode address in
3430 master's memory space.
Timur Tabif2717b42011-11-22 09:21:25 -06003431
J. German Riverab940ca62014-06-23 15:15:55 -07003432Freescale Layerscape Management Complex Firmware Support:
3433---------------------------------------------------------
3434The Freescale Layerscape Management Complex (MC) supports the loading of
3435"firmware".
3436This firmware often needs to be loaded during U-Boot booting, so macros
3437are used to identify the storage device (NOR flash, SPI, etc) and the address
3438within that device.
3439
3440- CONFIG_FSL_MC_ENET
3441 Enable the MC driver for Layerscape SoCs.
3442
Prabhakar Kushwaha5c055082015-06-02 10:55:52 +05303443Freescale Layerscape Debug Server Support:
3444-------------------------------------------
3445The Freescale Layerscape Debug Server Support supports the loading of
3446"Debug Server firmware" and triggering SP boot-rom.
3447This firmware often needs to be loaded during U-Boot booting.
3448
York Sunc0492142015-12-07 11:08:58 -08003449- CONFIG_SYS_MC_RSV_MEM_ALIGN
3450 Define alignment of reserved memory MC requires
Prabhakar Kushwaha5c055082015-06-02 10:55:52 +05303451
Paul Kocialkowskif3f431a2015-07-26 18:48:15 +02003452Reproducible builds
3453-------------------
3454
3455In order to achieve reproducible builds, timestamps used in the U-Boot build
3456process have to be set to a fixed value.
3457
3458This is done using the SOURCE_DATE_EPOCH environment variable.
3459SOURCE_DATE_EPOCH is to be set on the build host's shell, not as a configuration
3460option for U-Boot or an environment variable in U-Boot.
3461
3462SOURCE_DATE_EPOCH should be set to a number of seconds since the epoch, in UTC.
3463
wdenkc6097192002-11-03 00:24:07 +00003464Building the Software:
3465======================
3466
Wolfgang Denk218ca722008-03-26 10:40:12 +01003467Building U-Boot has been tested in several native build environments
3468and in many different cross environments. Of course we cannot support
3469all possibly existing versions of cross development tools in all
3470(potentially obsolete) versions. In case of tool chain problems we
3471recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK)
3472which is extensively used to build and test U-Boot.
wdenkc6097192002-11-03 00:24:07 +00003473
Wolfgang Denk218ca722008-03-26 10:40:12 +01003474If you are not using a native environment, it is assumed that you
3475have GNU cross compiling tools available in your path. In this case,
3476you must set the environment variable CROSS_COMPILE in your shell.
3477Note that no changes to the Makefile or any other source files are
3478necessary. For example using the ELDK on a 4xx CPU, please enter:
wdenkc6097192002-11-03 00:24:07 +00003479
Wolfgang Denk218ca722008-03-26 10:40:12 +01003480 $ CROSS_COMPILE=ppc_4xx-
3481 $ export CROSS_COMPILE
wdenkc6097192002-11-03 00:24:07 +00003482
Peter Tyser2f8d3962009-03-13 18:54:51 -05003483Note: If you wish to generate Windows versions of the utilities in
3484 the tools directory you can use the MinGW toolchain
3485 (http://www.mingw.org). Set your HOST tools to the MinGW
3486 toolchain and execute 'make tools'. For example:
3487
3488 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools
3489
3490 Binaries such as tools/mkimage.exe will be created which can
3491 be executed on computers running Windows.
3492
Wolfgang Denk218ca722008-03-26 10:40:12 +01003493U-Boot is intended to be simple to build. After installing the
3494sources you must configure U-Boot for one specific board type. This
wdenkc6097192002-11-03 00:24:07 +00003495is done by typing:
3496
Holger Freytherab584d62014-08-04 09:26:05 +02003497 make NAME_defconfig
wdenkc6097192002-11-03 00:24:07 +00003498
Holger Freytherab584d62014-08-04 09:26:05 +02003499where "NAME_defconfig" is the name of one of the existing configu-
Michael Jones4d675ae2012-03-15 22:48:10 +00003500rations; see boards.cfg for supported names.
wdenk54387ac2003-10-08 22:45:44 +00003501
wdenk2729af92004-05-03 20:45:30 +00003502Note: for some board special configuration names may exist; check if
3503 additional information is available from the board vendor; for
3504 instance, the TQM823L systems are available without (standard)
3505 or with LCD support. You can select such additional "features"
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02003506 when choosing the configuration, i. e.
wdenkc6097192002-11-03 00:24:07 +00003507
Holger Freytherab584d62014-08-04 09:26:05 +02003508 make TQM823L_defconfig
wdenk2729af92004-05-03 20:45:30 +00003509 - will configure for a plain TQM823L, i. e. no LCD support
wdenkc6097192002-11-03 00:24:07 +00003510
Holger Freytherab584d62014-08-04 09:26:05 +02003511 make TQM823L_LCD_defconfig
wdenk2729af92004-05-03 20:45:30 +00003512 - will configure for a TQM823L with U-Boot console on LCD
wdenkc6097192002-11-03 00:24:07 +00003513
wdenk2729af92004-05-03 20:45:30 +00003514 etc.
wdenkc6097192002-11-03 00:24:07 +00003515
wdenkc6097192002-11-03 00:24:07 +00003516
wdenk2729af92004-05-03 20:45:30 +00003517Finally, type "make all", and you should get some working U-Boot
3518images ready for download to / installation on your system:
wdenkc6097192002-11-03 00:24:07 +00003519
wdenk2729af92004-05-03 20:45:30 +00003520- "u-boot.bin" is a raw binary image
3521- "u-boot" is an image in ELF binary format
3522- "u-boot.srec" is in Motorola S-Record format
wdenkc6097192002-11-03 00:24:07 +00003523
Marian Balakowiczbaf31242006-09-07 17:25:40 +02003524By default the build is performed locally and the objects are saved
3525in the source directory. One of the two methods can be used to change
3526this behavior and build U-Boot to some external directory:
3527
35281. Add O= to the make command line invocations:
3529
3530 make O=/tmp/build distclean
Holger Freytherab584d62014-08-04 09:26:05 +02003531 make O=/tmp/build NAME_defconfig
Marian Balakowiczbaf31242006-09-07 17:25:40 +02003532 make O=/tmp/build all
3533
Timo Ketolaadbba992014-11-06 14:39:05 +020035342. Set environment variable KBUILD_OUTPUT to point to the desired location:
Marian Balakowiczbaf31242006-09-07 17:25:40 +02003535
Timo Ketolaadbba992014-11-06 14:39:05 +02003536 export KBUILD_OUTPUT=/tmp/build
Marian Balakowiczbaf31242006-09-07 17:25:40 +02003537 make distclean
Holger Freytherab584d62014-08-04 09:26:05 +02003538 make NAME_defconfig
Marian Balakowiczbaf31242006-09-07 17:25:40 +02003539 make all
3540
Timo Ketolaadbba992014-11-06 14:39:05 +02003541Note that the command line "O=" setting overrides the KBUILD_OUTPUT environment
Marian Balakowiczbaf31242006-09-07 17:25:40 +02003542variable.
3543
Daniel Schwierzeck215bb1c2018-01-26 16:31:04 +01003544User specific CPPFLAGS, AFLAGS and CFLAGS can be passed to the compiler by
3545setting the according environment variables KCPPFLAGS, KAFLAGS and KCFLAGS.
3546For example to treat all compiler warnings as errors:
3547
3548 make KCFLAGS=-Werror
wdenkc6097192002-11-03 00:24:07 +00003549
wdenk2729af92004-05-03 20:45:30 +00003550Please be aware that the Makefiles assume you are using GNU make, so
3551for instance on NetBSD you might need to use "gmake" instead of
3552native "make".
wdenkc6097192002-11-03 00:24:07 +00003553
wdenkc6097192002-11-03 00:24:07 +00003554
wdenk2729af92004-05-03 20:45:30 +00003555If the system board that you have is not listed, then you will need
3556to port U-Boot to your hardware platform. To do this, follow these
3557steps:
wdenkc6097192002-11-03 00:24:07 +00003558
Phil Sutter3c1496c2015-12-25 14:41:18 +010035591. Create a new directory to hold your board specific code. Add any
wdenk2729af92004-05-03 20:45:30 +00003560 files you need. In your board directory, you will need at least
Phil Sutter3c1496c2015-12-25 14:41:18 +01003561 the "Makefile" and a "<board>.c".
35622. Create a new configuration file "include/configs/<board>.h" for
3563 your board.
wdenk2729af92004-05-03 20:45:30 +000035643. If you're porting U-Boot to a new CPU, then also create a new
3565 directory to hold your CPU specific code. Add any files you need.
Holger Freytherab584d62014-08-04 09:26:05 +020035664. Run "make <board>_defconfig" with your new name.
wdenk2729af92004-05-03 20:45:30 +000035675. Type "make", and you should get a working "u-boot.srec" file
3568 to be installed on your target system.
35696. Debug and solve any problems that might arise.
3570 [Of course, this last step is much harder than it sounds.]
wdenkc6097192002-11-03 00:24:07 +00003571
wdenkc6097192002-11-03 00:24:07 +00003572
wdenk2729af92004-05-03 20:45:30 +00003573Testing of U-Boot Modifications, Ports to New Hardware, etc.:
3574==============================================================
wdenkc6097192002-11-03 00:24:07 +00003575
Wolfgang Denk218ca722008-03-26 10:40:12 +01003576If you have modified U-Boot sources (for instance added a new board
3577or support for new devices, a new CPU, etc.) you are expected to
wdenk2729af92004-05-03 20:45:30 +00003578provide feedback to the other developers. The feedback normally takes
3579the form of a "patch", i. e. a context diff against a certain (latest
Wolfgang Denk218ca722008-03-26 10:40:12 +01003580official or latest in the git repository) version of U-Boot sources.
wdenkc6097192002-11-03 00:24:07 +00003581
Wolfgang Denk218ca722008-03-26 10:40:12 +01003582But before you submit such a patch, please verify that your modifi-
3583cation did not break existing code. At least make sure that *ALL* of
wdenk2729af92004-05-03 20:45:30 +00003584the supported boards compile WITHOUT ANY compiler warnings. To do so,
Simon Glass6de80f22016-07-27 20:33:08 -06003585just run the buildman script (tools/buildman/buildman), which will
3586configure and build U-Boot for ALL supported system. Be warned, this
3587will take a while. Please see the buildman README, or run 'buildman -H'
3588for documentation.
Marian Balakowiczbaf31242006-09-07 17:25:40 +02003589
3590
wdenk2729af92004-05-03 20:45:30 +00003591See also "U-Boot Porting Guide" below.
wdenkc6097192002-11-03 00:24:07 +00003592
wdenkc6097192002-11-03 00:24:07 +00003593
wdenk2729af92004-05-03 20:45:30 +00003594Monitor Commands - Overview:
3595============================
wdenkc6097192002-11-03 00:24:07 +00003596
wdenk2729af92004-05-03 20:45:30 +00003597go - start application at address 'addr'
3598run - run commands in an environment variable
3599bootm - boot application image from memory
3600bootp - boot image via network using BootP/TFTP protocol
Marek Vasut44f074c2012-03-14 21:52:45 +00003601bootz - boot zImage from memory
wdenk2729af92004-05-03 20:45:30 +00003602tftpboot- boot image via network using TFTP protocol
3603 and env variables "ipaddr" and "serverip"
3604 (and eventually "gatewayip")
Simon Glass1fb7cd42011-10-24 18:00:07 +00003605tftpput - upload a file via network using TFTP protocol
wdenk2729af92004-05-03 20:45:30 +00003606rarpboot- boot image via network using RARP/TFTP protocol
3607diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
3608loads - load S-Record file over serial line
3609loadb - load binary file over serial line (kermit mode)
3610md - memory display
3611mm - memory modify (auto-incrementing)
3612nm - memory modify (constant address)
3613mw - memory write (fill)
3614cp - memory copy
3615cmp - memory compare
3616crc32 - checksum calculation
Peter Tyser0f89c542009-04-18 22:34:03 -05003617i2c - I2C sub-system
wdenk2729af92004-05-03 20:45:30 +00003618sspi - SPI utility commands
3619base - print or set address offset
3620printenv- print environment variables
3621setenv - set environment variables
3622saveenv - save environment variables to persistent storage
3623protect - enable or disable FLASH write protection
3624erase - erase FLASH memory
3625flinfo - print FLASH memory information
Karl O. Pinc10635af2012-08-03 05:57:21 +00003626nand - NAND memory operations (see doc/README.nand)
wdenk2729af92004-05-03 20:45:30 +00003627bdinfo - print Board Info structure
3628iminfo - print header information for application image
3629coninfo - print console devices and informations
3630ide - IDE sub-system
3631loop - infinite loop on address range
wdenk56523f12004-07-11 17:40:54 +00003632loopw - infinite write loop on address range
wdenk2729af92004-05-03 20:45:30 +00003633mtest - simple RAM test
3634icache - enable or disable instruction cache
3635dcache - enable or disable data cache
3636reset - Perform RESET of the CPU
3637echo - echo args to console
3638version - print monitor version
3639help - print online help
3640? - alias for 'help'
wdenkc6097192002-11-03 00:24:07 +00003641
wdenkc6097192002-11-03 00:24:07 +00003642
wdenk2729af92004-05-03 20:45:30 +00003643Monitor Commands - Detailed Description:
3644========================================
wdenkc6097192002-11-03 00:24:07 +00003645
wdenk2729af92004-05-03 20:45:30 +00003646TODO.
wdenkc6097192002-11-03 00:24:07 +00003647
wdenk2729af92004-05-03 20:45:30 +00003648For now: just type "help <command>".
wdenkc6097192002-11-03 00:24:07 +00003649
3650
wdenk2729af92004-05-03 20:45:30 +00003651Environment Variables:
3652======================
wdenkc6097192002-11-03 00:24:07 +00003653
wdenk2729af92004-05-03 20:45:30 +00003654U-Boot supports user configuration using Environment Variables which
3655can be made persistent by saving to Flash memory.
wdenkc6097192002-11-03 00:24:07 +00003656
wdenk2729af92004-05-03 20:45:30 +00003657Environment Variables are set using "setenv", printed using
3658"printenv", and saved to Flash using "saveenv". Using "setenv"
3659without a value can be used to delete a variable from the
3660environment. As long as you don't save the environment you are
3661working with an in-memory copy. In case the Flash area containing the
3662environment is erased by accident, a default environment is provided.
wdenkc6097192002-11-03 00:24:07 +00003663
Wolfgang Denkc96f86e2010-01-17 23:55:53 +01003664Some configuration options can be set using Environment Variables.
3665
3666List of environment variables (most likely not complete):
wdenkc6097192002-11-03 00:24:07 +00003667
wdenk2729af92004-05-03 20:45:30 +00003668 baudrate - see CONFIG_BAUDRATE
wdenkc6097192002-11-03 00:24:07 +00003669
wdenk2729af92004-05-03 20:45:30 +00003670 bootdelay - see CONFIG_BOOTDELAY
wdenkc6097192002-11-03 00:24:07 +00003671
wdenk2729af92004-05-03 20:45:30 +00003672 bootcmd - see CONFIG_BOOTCOMMAND
wdenkc6097192002-11-03 00:24:07 +00003673
wdenk2729af92004-05-03 20:45:30 +00003674 bootargs - Boot arguments when booting an RTOS image
wdenkc6097192002-11-03 00:24:07 +00003675
wdenk2729af92004-05-03 20:45:30 +00003676 bootfile - Name of the image to load with TFTP
wdenkc6097192002-11-03 00:24:07 +00003677
Bartlomiej Sieka7d721e32008-04-14 15:44:16 +02003678 bootm_low - Memory range available for image processing in the bootm
3679 command can be restricted. This variable is given as
3680 a hexadecimal number and defines lowest address allowed
3681 for use by the bootm command. See also "bootm_size"
3682 environment variable. Address defined by "bootm_low" is
3683 also the base of the initial memory mapping for the Linux
Grant Likelyc3624e62011-03-28 09:58:43 +00003684 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and
3685 bootm_mapsize.
3686
Wolfgang Denkc0f40852011-10-26 10:21:21 +00003687 bootm_mapsize - Size of the initial memory mapping for the Linux kernel.
Grant Likelyc3624e62011-03-28 09:58:43 +00003688 This variable is given as a hexadecimal number and it
3689 defines the size of the memory region starting at base
3690 address bootm_low that is accessible by the Linux kernel
3691 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used
3692 as the default value if it is defined, and bootm_size is
3693 used otherwise.
Bartlomiej Sieka7d721e32008-04-14 15:44:16 +02003694
3695 bootm_size - Memory range available for image processing in the bootm
3696 command can be restricted. This variable is given as
3697 a hexadecimal number and defines the size of the region
3698 allowed for use by the bootm command. See also "bootm_low"
3699 environment variable.
3700
Bartlomiej Sieka4bae9092008-10-01 15:26:31 +02003701 updatefile - Location of the software update file on a TFTP server, used
3702 by the automatic software update feature. Please refer to
3703 documentation in doc/README.update for more details.
3704
wdenk2729af92004-05-03 20:45:30 +00003705 autoload - if set to "no" (any string beginning with 'n'),
3706 "bootp" will just load perform a lookup of the
3707 configuration from the BOOTP server, but not try to
3708 load any image using TFTP
wdenkc6097192002-11-03 00:24:07 +00003709
wdenk2729af92004-05-03 20:45:30 +00003710 autostart - if set to "yes", an image loaded using the "bootp",
3711 "rarpboot", "tftpboot" or "diskboot" commands will
3712 be automatically started (by internally calling
3713 "bootm")
wdenkc6097192002-11-03 00:24:07 +00003714
wdenk2729af92004-05-03 20:45:30 +00003715 If set to "no", a standalone image passed to the
3716 "bootm" command will be copied to the load address
3717 (and eventually uncompressed), but NOT be started.
3718 This can be used to load and uncompress arbitrary
3719 data.
wdenkc6097192002-11-03 00:24:07 +00003720
David A. Longa28afca2011-07-09 16:40:19 -04003721 fdt_high - if set this restricts the maximum address that the
3722 flattened device tree will be copied into upon boot.
Shawn Guofa34f6b2012-01-09 21:54:08 +00003723 For example, if you have a system with 1 GB memory
3724 at physical address 0x10000000, while Linux kernel
3725 only recognizes the first 704 MB as low memory, you
3726 may need to set fdt_high as 0x3C000000 to have the
3727 device tree blob be copied to the maximum address
3728 of the 704 MB low memory, so that Linux kernel can
3729 access it during the boot procedure.
3730
David A. Longa28afca2011-07-09 16:40:19 -04003731 If this is set to the special value 0xFFFFFFFF then
3732 the fdt will not be copied at all on boot. For this
3733 to work it must reside in writable memory, have
3734 sufficient padding on the end of it for u-boot to
3735 add the information it needs into it, and the memory
3736 must be accessible by the kernel.
3737
Simon Glasseea63e02011-10-24 19:15:34 +00003738 fdtcontroladdr- if set this is the address of the control flattened
3739 device tree used by U-Boot when CONFIG_OF_CONTROL is
3740 defined.
3741
wdenk17ea1172004-06-06 21:51:03 +00003742 i2cfast - (PPC405GP|PPC405EP only)
3743 if set to 'y' configures Linux I2C driver for fast
3744 mode (400kHZ). This environment variable is used in
3745 initialization code. So, for changes to be effective
3746 it must be saved and board must be reset.
3747
wdenk2729af92004-05-03 20:45:30 +00003748 initrd_high - restrict positioning of initrd images:
3749 If this variable is not set, initrd images will be
3750 copied to the highest possible address in RAM; this
3751 is usually what you want since it allows for
3752 maximum initrd size. If for some reason you want to
3753 make sure that the initrd image is loaded below the
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003754 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment
wdenk2729af92004-05-03 20:45:30 +00003755 variable to a value of "no" or "off" or "0".
3756 Alternatively, you can set it to a maximum upper
3757 address to use (U-Boot will still check that it
3758 does not overwrite the U-Boot stack and data).
wdenkc6097192002-11-03 00:24:07 +00003759
wdenk2729af92004-05-03 20:45:30 +00003760 For instance, when you have a system with 16 MB
3761 RAM, and want to reserve 4 MB from use by Linux,
3762 you can do this by adding "mem=12M" to the value of
3763 the "bootargs" variable. However, now you must make
3764 sure that the initrd image is placed in the first
3765 12 MB as well - this can be done with
wdenkc6097192002-11-03 00:24:07 +00003766
wdenk2729af92004-05-03 20:45:30 +00003767 setenv initrd_high 00c00000
wdenkc6097192002-11-03 00:24:07 +00003768
wdenk2729af92004-05-03 20:45:30 +00003769 If you set initrd_high to 0xFFFFFFFF, this is an
3770 indication to U-Boot that all addresses are legal
3771 for the Linux kernel, including addresses in flash
3772 memory. In this case U-Boot will NOT COPY the
3773 ramdisk at all. This may be useful to reduce the
3774 boot time on your system, but requires that this
3775 feature is supported by your Linux kernel.
wdenk4a6fd342003-04-12 23:38:12 +00003776
wdenk2729af92004-05-03 20:45:30 +00003777 ipaddr - IP address; needed for tftpboot command
wdenkc6097192002-11-03 00:24:07 +00003778
wdenk2729af92004-05-03 20:45:30 +00003779 loadaddr - Default load address for commands like "bootp",
3780 "rarpboot", "tftpboot", "loadb" or "diskboot"
wdenkc6097192002-11-03 00:24:07 +00003781
wdenk2729af92004-05-03 20:45:30 +00003782 loads_echo - see CONFIG_LOADS_ECHO
wdenkc6097192002-11-03 00:24:07 +00003783
wdenk2729af92004-05-03 20:45:30 +00003784 serverip - TFTP server IP address; needed for tftpboot command
wdenk38b99262003-05-23 23:18:21 +00003785
wdenk2729af92004-05-03 20:45:30 +00003786 bootretry - see CONFIG_BOOT_RETRY_TIME
wdenkc6097192002-11-03 00:24:07 +00003787
wdenk2729af92004-05-03 20:45:30 +00003788 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
wdenkc6097192002-11-03 00:24:07 +00003789
wdenk2729af92004-05-03 20:45:30 +00003790 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
wdenkc6097192002-11-03 00:24:07 +00003791
Mike Frysingere2a53452011-10-02 10:01:27 +00003792 ethprime - controls which interface is used first.
wdenkc6097192002-11-03 00:24:07 +00003793
Mike Frysingere2a53452011-10-02 10:01:27 +00003794 ethact - controls which interface is currently active.
3795 For example you can do the following
wdenkc6097192002-11-03 00:24:07 +00003796
Heiko Schocher48690d82010-07-20 17:45:02 +02003797 => setenv ethact FEC
3798 => ping 192.168.0.1 # traffic sent on FEC
3799 => setenv ethact SCC
3800 => ping 10.0.0.1 # traffic sent on SCC
wdenkc6097192002-11-03 00:24:07 +00003801
Matthias Fuchse1692572008-01-17 07:45:05 +01003802 ethrotate - When set to "no" U-Boot does not go through all
3803 available network interfaces.
3804 It just stays at the currently selected interface.
3805
Wolfgang Denkc96f86e2010-01-17 23:55:53 +01003806 netretry - When set to "no" each network operation will
wdenk2729af92004-05-03 20:45:30 +00003807 either succeed or fail without retrying.
3808 When set to "once" the network operation will
3809 fail when all the available network interfaces
3810 are tried once without success.
3811 Useful on scripts which control the retry operation
3812 themselves.
wdenkc6097192002-11-03 00:24:07 +00003813
Jean-Christophe PLAGNIOL-VILLARDb4e2f892009-01-31 09:53:39 +01003814 npe_ucode - set load address for the NPE microcode
Jean-Christophe PLAGNIOL-VILLARDa1cf0272008-01-07 08:41:34 +01003815
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08003816 silent_linux - If set then Linux will be told to boot silently, by
Simon Glass8d51aac2013-07-16 20:10:00 -07003817 changing the console to be empty. If "yes" it will be
3818 made silent. If "no" it will not be made silent. If
3819 unset, then it will be made silent if the U-Boot console
3820 is silent.
3821
Albert ARIBAUD \(3ADEV\)f5fb7342015-10-12 00:02:57 +02003822 tftpsrcp - If this is set, the value is used for TFTP's
Wolfgang Denkecb0ccd2005-09-24 22:37:32 +02003823 UDP source port.
3824
Albert ARIBAUD \(3ADEV\)f5fb7342015-10-12 00:02:57 +02003825 tftpdstp - If this is set, the value is used for TFTP's UDP
Wolfgang Denk28cb9372005-09-24 23:25:46 +02003826 destination port instead of the Well Know Port 69.
3827
Wolfgang Denkc96f86e2010-01-17 23:55:53 +01003828 tftpblocksize - Block size to use for TFTP transfers; if not set,
3829 we use the TFTP server's default block size
3830
3831 tftptimeout - Retransmission timeout for TFTP packets (in milli-
3832 seconds, minimum value is 1000 = 1 second). Defines
3833 when a packet is considered to be lost so it has to
3834 be retransmitted. The default is 5000 = 5 seconds.
3835 Lowering this value may make downloads succeed
3836 faster in networks with high packet loss rates or
3837 with unreliable TFTP servers.
3838
Albert ARIBAUD \(3ADEV\)f5fb7342015-10-12 00:02:57 +02003839 tftptimeoutcountmax - maximum count of TFTP timeouts (no
3840 unit, minimum value = 0). Defines how many timeouts
3841 can happen during a single file transfer before that
3842 transfer is aborted. The default is 10, and 0 means
3843 'no timeouts allowed'. Increasing this value may help
3844 downloads succeed with high packet loss rates, or with
3845 unreliable TFTP servers or client hardware.
3846
Wolfgang Denkc96f86e2010-01-17 23:55:53 +01003847 vlan - When set to a value < 4095 the traffic over
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02003848 Ethernet is encapsulated/received over 802.1q
wdenk2729af92004-05-03 20:45:30 +00003849 VLAN tagged frames.
wdenka3d991b2004-04-15 21:48:45 +00003850
Alexandre Messier50768f52016-02-01 17:08:57 -05003851 bootpretryperiod - Period during which BOOTP/DHCP sends retries.
3852 Unsigned value, in milliseconds. If not set, the period will
3853 be either the default (28000), or a value based on
3854 CONFIG_NET_RETRY_COUNT, if defined. This value has
3855 precedence over the valu based on CONFIG_NET_RETRY_COUNT.
3856
Jason Hobbsdc0b7b02011-08-31 05:37:28 +00003857The following image location variables contain the location of images
3858used in booting. The "Image" column gives the role of the image and is
3859not an environment variable name. The other columns are environment
3860variable names. "File Name" gives the name of the file on a TFTP
3861server, "RAM Address" gives the location in RAM the image will be
3862loaded to, and "Flash Location" gives the image's address in NOR
3863flash or offset in NAND flash.
3864
3865*Note* - these variables don't have to be defined for all boards, some
Fabio Estevamaed9fed2015-04-25 18:53:10 -03003866boards currently use other variables for these purposes, and some
Jason Hobbsdc0b7b02011-08-31 05:37:28 +00003867boards use these variables for other purposes.
3868
Wolfgang Denkc0f40852011-10-26 10:21:21 +00003869Image File Name RAM Address Flash Location
3870----- --------- ----------- --------------
3871u-boot u-boot u-boot_addr_r u-boot_addr
3872Linux kernel bootfile kernel_addr_r kernel_addr
3873device tree blob fdtfile fdt_addr_r fdt_addr
3874ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr
Jason Hobbsdc0b7b02011-08-31 05:37:28 +00003875
wdenk2729af92004-05-03 20:45:30 +00003876The following environment variables may be used and automatically
3877updated by the network boot commands ("bootp" and "rarpboot"),
3878depending the information provided by your boot server:
wdenka3d991b2004-04-15 21:48:45 +00003879
wdenk2729af92004-05-03 20:45:30 +00003880 bootfile - see above
3881 dnsip - IP address of your Domain Name Server
3882 dnsip2 - IP address of your secondary Domain Name Server
3883 gatewayip - IP address of the Gateway (Router) to use
3884 hostname - Target hostname
3885 ipaddr - see above
3886 netmask - Subnet Mask
3887 rootpath - Pathname of the root filesystem on the NFS server
3888 serverip - see above
wdenka3d991b2004-04-15 21:48:45 +00003889
wdenka3d991b2004-04-15 21:48:45 +00003890
wdenk2729af92004-05-03 20:45:30 +00003891There are two special Environment Variables:
wdenkc6097192002-11-03 00:24:07 +00003892
wdenk2729af92004-05-03 20:45:30 +00003893 serial# - contains hardware identification information such
3894 as type string and/or serial number
3895 ethaddr - Ethernet address
wdenkc6097192002-11-03 00:24:07 +00003896
wdenk2729af92004-05-03 20:45:30 +00003897These variables can be set only once (usually during manufacturing of
3898the board). U-Boot refuses to delete or overwrite these variables
3899once they have been set once.
wdenkc6097192002-11-03 00:24:07 +00003900
3901
wdenk2729af92004-05-03 20:45:30 +00003902Further special Environment Variables:
wdenkc6097192002-11-03 00:24:07 +00003903
wdenk2729af92004-05-03 20:45:30 +00003904 ver - Contains the U-Boot version string as printed
3905 with the "version" command. This variable is
3906 readonly (see CONFIG_VERSION_VARIABLE).
wdenkc6097192002-11-03 00:24:07 +00003907
wdenkc6097192002-11-03 00:24:07 +00003908
wdenk2729af92004-05-03 20:45:30 +00003909Please note that changes to some configuration parameters may take
3910only effect after the next boot (yes, that's just like Windoze :-).
wdenkc6097192002-11-03 00:24:07 +00003911
stroesec1551ea2003-04-04 15:53:41 +00003912
Joe Hershberger170ab112012-12-11 22:16:24 -06003913Callback functions for environment variables:
3914---------------------------------------------
3915
3916For some environment variables, the behavior of u-boot needs to change
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08003917when their values are changed. This functionality allows functions to
Joe Hershberger170ab112012-12-11 22:16:24 -06003918be associated with arbitrary variables. On creation, overwrite, or
3919deletion, the callback will provide the opportunity for some side
3920effect to happen or for the change to be rejected.
3921
3922The callbacks are named and associated with a function using the
3923U_BOOT_ENV_CALLBACK macro in your board or driver code.
3924
3925These callbacks are associated with variables in one of two ways. The
3926static list can be added to by defining CONFIG_ENV_CALLBACK_LIST_STATIC
3927in the board configuration to a string that defines a list of
3928associations. The list must be in the following format:
3929
3930 entry = variable_name[:callback_name]
3931 list = entry[,list]
3932
3933If the callback name is not specified, then the callback is deleted.
3934Spaces are also allowed anywhere in the list.
3935
3936Callbacks can also be associated by defining the ".callbacks" variable
3937with the same list format above. Any association in ".callbacks" will
3938override any association in the static list. You can define
3939CONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08003940".callbacks" environment variable in the default or embedded environment.
Joe Hershberger170ab112012-12-11 22:16:24 -06003941
Joe Hershbergerbdf1fe42015-05-20 14:27:20 -05003942If CONFIG_REGEX is defined, the variable_name above is evaluated as a
3943regular expression. This allows multiple variables to be connected to
3944the same callback without explicitly listing them all out.
3945
Joe Hershberger170ab112012-12-11 22:16:24 -06003946
wdenk2729af92004-05-03 20:45:30 +00003947Command Line Parsing:
3948=====================
stroesec1551ea2003-04-04 15:53:41 +00003949
wdenk2729af92004-05-03 20:45:30 +00003950There are two different command line parsers available with U-Boot:
3951the old "simple" one, and the much more powerful "hush" shell:
stroesec1551ea2003-04-04 15:53:41 +00003952
wdenk2729af92004-05-03 20:45:30 +00003953Old, simple command line parser:
3954--------------------------------
wdenkc6097192002-11-03 00:24:07 +00003955
wdenk2729af92004-05-03 20:45:30 +00003956- supports environment variables (through setenv / saveenv commands)
3957- several commands on one line, separated by ';'
Wolfgang Denkfe126d82005-11-20 21:40:11 +01003958- variable substitution using "... ${name} ..." syntax
wdenk2729af92004-05-03 20:45:30 +00003959- special characters ('$', ';') can be escaped by prefixing with '\',
3960 for example:
Wolfgang Denkfe126d82005-11-20 21:40:11 +01003961 setenv bootcmd bootm \${address}
wdenk2729af92004-05-03 20:45:30 +00003962- You can also escape text by enclosing in single apostrophes, for example:
3963 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
wdenkc6097192002-11-03 00:24:07 +00003964
wdenk2729af92004-05-03 20:45:30 +00003965Hush shell:
3966-----------
wdenkf07771c2003-05-28 08:06:31 +00003967
wdenk2729af92004-05-03 20:45:30 +00003968- similar to Bourne shell, with control structures like
3969 if...then...else...fi, for...do...done; while...do...done,
3970 until...do...done, ...
3971- supports environment ("global") variables (through setenv / saveenv
3972 commands) and local shell variables (through standard shell syntax
3973 "name=value"); only environment variables can be used with "run"
3974 command
wdenkf07771c2003-05-28 08:06:31 +00003975
wdenk2729af92004-05-03 20:45:30 +00003976General rules:
3977--------------
wdenkf07771c2003-05-28 08:06:31 +00003978
wdenk2729af92004-05-03 20:45:30 +00003979(1) If a command line (or an environment variable executed by a "run"
3980 command) contains several commands separated by semicolon, and
3981 one of these commands fails, then the remaining commands will be
3982 executed anyway.
wdenkf07771c2003-05-28 08:06:31 +00003983
wdenk2729af92004-05-03 20:45:30 +00003984(2) If you execute several variables with one call to run (i. e.
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02003985 calling run with a list of variables as arguments), any failing
wdenk2729af92004-05-03 20:45:30 +00003986 command will cause "run" to terminate, i. e. the remaining
3987 variables are not executed.
wdenkf07771c2003-05-28 08:06:31 +00003988
wdenk2729af92004-05-03 20:45:30 +00003989Note for Redundant Ethernet Interfaces:
3990=======================================
wdenkf07771c2003-05-28 08:06:31 +00003991
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02003992Some boards come with redundant Ethernet interfaces; U-Boot supports
wdenk2729af92004-05-03 20:45:30 +00003993such configurations and is capable of automatic selection of a
3994"working" interface when needed. MAC assignment works as follows:
wdenkf07771c2003-05-28 08:06:31 +00003995
wdenk2729af92004-05-03 20:45:30 +00003996Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
3997MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
3998"eth1addr" (=>eth1), "eth2addr", ...
wdenkf07771c2003-05-28 08:06:31 +00003999
wdenk2729af92004-05-03 20:45:30 +00004000If the network interface stores some valid MAC address (for instance
4001in SROM), this is used as default address if there is NO correspon-
4002ding setting in the environment; if the corresponding environment
4003variable is set, this overrides the settings in the card; that means:
wdenkf07771c2003-05-28 08:06:31 +00004004
wdenk2729af92004-05-03 20:45:30 +00004005o If the SROM has a valid MAC address, and there is no address in the
4006 environment, the SROM's address is used.
wdenkc6097192002-11-03 00:24:07 +00004007
wdenk2729af92004-05-03 20:45:30 +00004008o If there is no valid address in the SROM, and a definition in the
4009 environment exists, then the value from the environment variable is
4010 used.
wdenkc6097192002-11-03 00:24:07 +00004011
wdenk2729af92004-05-03 20:45:30 +00004012o If both the SROM and the environment contain a MAC address, and
4013 both addresses are the same, this MAC address is used.
wdenkc6097192002-11-03 00:24:07 +00004014
wdenk2729af92004-05-03 20:45:30 +00004015o If both the SROM and the environment contain a MAC address, and the
4016 addresses differ, the value from the environment is used and a
4017 warning is printed.
wdenkc6097192002-11-03 00:24:07 +00004018
wdenk2729af92004-05-03 20:45:30 +00004019o If neither SROM nor the environment contain a MAC address, an error
Joe Hershbergerbef10142015-05-04 14:55:13 -05004020 is raised. If CONFIG_NET_RANDOM_ETHADDR is defined, then in this case
4021 a random, locally-assigned MAC is used.
wdenkc6097192002-11-03 00:24:07 +00004022
Ben Warrenecee9322010-04-26 11:11:46 -07004023If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses
Wolfgang Denkc0f40852011-10-26 10:21:21 +00004024will be programmed into hardware as part of the initialization process. This
Ben Warrenecee9322010-04-26 11:11:46 -07004025may be skipped by setting the appropriate 'ethmacskip' environment variable.
4026The naming convention is as follows:
4027"ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc.
wdenkc6097192002-11-03 00:24:07 +00004028
wdenk2729af92004-05-03 20:45:30 +00004029Image Formats:
4030==============
wdenkc6097192002-11-03 00:24:07 +00004031
Marian Balakowicz3310c542008-03-12 12:13:13 +01004032U-Boot is capable of booting (and performing other auxiliary operations on)
4033images in two formats:
4034
4035New uImage format (FIT)
4036-----------------------
4037
4038Flexible and powerful format based on Flattened Image Tree -- FIT (similar
4039to Flattened Device Tree). It allows the use of images with multiple
4040components (several kernels, ramdisks, etc.), with contents protected by
4041SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
4042
4043
4044Old uImage format
4045-----------------
4046
4047Old image format is based on binary files which can be basically anything,
4048preceded by a special header; see the definitions in include/image.h for
4049details; basically, the header defines the following image properties:
wdenkc6097192002-11-03 00:24:07 +00004050
wdenk2729af92004-05-03 20:45:30 +00004051* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
4052 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
Peter Tyserf5ed9e32008-09-08 14:56:49 -05004053 LynxOS, pSOS, QNX, RTEMS, INTEGRITY;
4054 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS,
4055 INTEGRITY).
Andy Shevchenkodaab59a2017-07-05 16:25:22 +03004056* Target CPU Architecture (Provisions for Alpha, ARM, Intel x86,
Macpaul Linafc1ce82011-10-19 20:41:11 +00004057 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
Andy Shevchenkodaab59a2017-07-05 16:25:22 +03004058 Currently supported: ARM, Intel x86, MIPS, NDS32, Nios II, PowerPC).
wdenk2729af92004-05-03 20:45:30 +00004059* Compression Type (uncompressed, gzip, bzip2)
4060* Load Address
4061* Entry Point
4062* Image Name
4063* Image Timestamp
wdenkc6097192002-11-03 00:24:07 +00004064
wdenk2729af92004-05-03 20:45:30 +00004065The header is marked by a special Magic Number, and both the header
4066and the data portions of the image are secured against corruption by
4067CRC32 checksums.
wdenkc6097192002-11-03 00:24:07 +00004068
wdenkc6097192002-11-03 00:24:07 +00004069
wdenk2729af92004-05-03 20:45:30 +00004070Linux Support:
4071==============
wdenkc6097192002-11-03 00:24:07 +00004072
wdenk2729af92004-05-03 20:45:30 +00004073Although U-Boot should support any OS or standalone application
4074easily, the main focus has always been on Linux during the design of
4075U-Boot.
wdenkc6097192002-11-03 00:24:07 +00004076
wdenk2729af92004-05-03 20:45:30 +00004077U-Boot includes many features that so far have been part of some
4078special "boot loader" code within the Linux kernel. Also, any
4079"initrd" images to be used are no longer part of one big Linux image;
4080instead, kernel and "initrd" are separate images. This implementation
4081serves several purposes:
wdenkc6097192002-11-03 00:24:07 +00004082
wdenk2729af92004-05-03 20:45:30 +00004083- the same features can be used for other OS or standalone
4084 applications (for instance: using compressed images to reduce the
4085 Flash memory footprint)
wdenkc6097192002-11-03 00:24:07 +00004086
wdenk2729af92004-05-03 20:45:30 +00004087- it becomes much easier to port new Linux kernel versions because
4088 lots of low-level, hardware dependent stuff are done by U-Boot
wdenkc6097192002-11-03 00:24:07 +00004089
wdenk2729af92004-05-03 20:45:30 +00004090- the same Linux kernel image can now be used with different "initrd"
4091 images; of course this also means that different kernel images can
4092 be run with the same "initrd". This makes testing easier (you don't
4093 have to build a new "zImage.initrd" Linux image when you just
4094 change a file in your "initrd"). Also, a field-upgrade of the
4095 software is easier now.
wdenkc6097192002-11-03 00:24:07 +00004096
wdenkc6097192002-11-03 00:24:07 +00004097
wdenk2729af92004-05-03 20:45:30 +00004098Linux HOWTO:
4099============
wdenkc6097192002-11-03 00:24:07 +00004100
wdenk2729af92004-05-03 20:45:30 +00004101Porting Linux to U-Boot based systems:
4102---------------------------------------
wdenkc6097192002-11-03 00:24:07 +00004103
wdenk2729af92004-05-03 20:45:30 +00004104U-Boot cannot save you from doing all the necessary modifications to
4105configure the Linux device drivers for use with your target hardware
4106(no, we don't intend to provide a full virtual machine interface to
4107Linux :-).
wdenkc6097192002-11-03 00:24:07 +00004108
Stefan Roesea47a12b2010-04-15 16:07:28 +02004109But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot).
wdenkc6097192002-11-03 00:24:07 +00004110
wdenk2729af92004-05-03 20:45:30 +00004111Just make sure your machine specific header file (for instance
4112include/asm-ppc/tqm8xx.h) includes the same definition of the Board
Markus Heidelberg1dc30692008-09-07 20:18:27 +02004113Information structure as we define in include/asm-<arch>/u-boot.h,
4114and make sure that your definition of IMAP_ADDR uses the same value
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02004115as your U-Boot configuration in CONFIG_SYS_IMMR.
wdenkc6097192002-11-03 00:24:07 +00004116
Simon Glass2eb31b12014-06-11 23:29:46 -06004117Note that U-Boot now has a driver model, a unified model for drivers.
4118If you are adding a new driver, plumb it into driver model. If there
4119is no uclass available, you are encouraged to create one. See
4120doc/driver-model.
4121
wdenkc6097192002-11-03 00:24:07 +00004122
wdenk2729af92004-05-03 20:45:30 +00004123Configuring the Linux kernel:
4124-----------------------------
wdenkc6097192002-11-03 00:24:07 +00004125
wdenk2729af92004-05-03 20:45:30 +00004126No specific requirements for U-Boot. Make sure you have some root
4127device (initial ramdisk, NFS) for your target system.
wdenkc6097192002-11-03 00:24:07 +00004128
wdenkc6097192002-11-03 00:24:07 +00004129
wdenk2729af92004-05-03 20:45:30 +00004130Building a Linux Image:
4131-----------------------
wdenkc6097192002-11-03 00:24:07 +00004132
wdenk2729af92004-05-03 20:45:30 +00004133With U-Boot, "normal" build targets like "zImage" or "bzImage" are
4134not used. If you use recent kernel source, a new build target
4135"uImage" will exist which automatically builds an image usable by
4136U-Boot. Most older kernels also have support for a "pImage" target,
4137which was introduced for our predecessor project PPCBoot and uses a
4138100% compatible format.
wdenkc6097192002-11-03 00:24:07 +00004139
wdenk2729af92004-05-03 20:45:30 +00004140Example:
wdenkc6097192002-11-03 00:24:07 +00004141
Holger Freytherab584d62014-08-04 09:26:05 +02004142 make TQM850L_defconfig
wdenk2729af92004-05-03 20:45:30 +00004143 make oldconfig
4144 make dep
4145 make uImage
wdenkc6097192002-11-03 00:24:07 +00004146
wdenk2729af92004-05-03 20:45:30 +00004147The "uImage" build target uses a special tool (in 'tools/mkimage') to
4148encapsulate a compressed Linux kernel image with header information,
4149CRC32 checksum etc. for use with U-Boot. This is what we are doing:
wdenkc6097192002-11-03 00:24:07 +00004150
wdenk2729af92004-05-03 20:45:30 +00004151* build a standard "vmlinux" kernel image (in ELF binary format):
wdenkc6097192002-11-03 00:24:07 +00004152
wdenk2729af92004-05-03 20:45:30 +00004153* convert the kernel into a raw binary image:
wdenkc6097192002-11-03 00:24:07 +00004154
wdenk2729af92004-05-03 20:45:30 +00004155 ${CROSS_COMPILE}-objcopy -O binary \
4156 -R .note -R .comment \
4157 -S vmlinux linux.bin
wdenkc6097192002-11-03 00:24:07 +00004158
wdenk2729af92004-05-03 20:45:30 +00004159* compress the binary image:
wdenkc6097192002-11-03 00:24:07 +00004160
wdenk2729af92004-05-03 20:45:30 +00004161 gzip -9 linux.bin
wdenkc6097192002-11-03 00:24:07 +00004162
wdenk2729af92004-05-03 20:45:30 +00004163* package compressed binary image for U-Boot:
wdenk24ee89b2002-11-03 17:56:27 +00004164
wdenk2729af92004-05-03 20:45:30 +00004165 mkimage -A ppc -O linux -T kernel -C gzip \
4166 -a 0 -e 0 -n "Linux Kernel Image" \
4167 -d linux.bin.gz uImage
wdenk24ee89b2002-11-03 17:56:27 +00004168
wdenk24ee89b2002-11-03 17:56:27 +00004169
wdenk2729af92004-05-03 20:45:30 +00004170The "mkimage" tool can also be used to create ramdisk images for use
4171with U-Boot, either separated from the Linux kernel image, or
4172combined into one file. "mkimage" encapsulates the images with a 64
4173byte header containing information about target architecture,
4174operating system, image type, compression method, entry points, time
4175stamp, CRC32 checksums, etc.
wdenk24ee89b2002-11-03 17:56:27 +00004176
wdenk2729af92004-05-03 20:45:30 +00004177"mkimage" can be called in two ways: to verify existing images and
4178print the header information, or to build new images.
wdenk24ee89b2002-11-03 17:56:27 +00004179
wdenk2729af92004-05-03 20:45:30 +00004180In the first form (with "-l" option) mkimage lists the information
4181contained in the header of an existing U-Boot image; this includes
4182checksum verification:
wdenk24ee89b2002-11-03 17:56:27 +00004183
wdenk2729af92004-05-03 20:45:30 +00004184 tools/mkimage -l image
4185 -l ==> list image header information
wdenk24ee89b2002-11-03 17:56:27 +00004186
wdenk2729af92004-05-03 20:45:30 +00004187The second form (with "-d" option) is used to build a U-Boot image
4188from a "data file" which is used as image payload:
wdenk24ee89b2002-11-03 17:56:27 +00004189
wdenk2729af92004-05-03 20:45:30 +00004190 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
4191 -n name -d data_file image
4192 -A ==> set architecture to 'arch'
4193 -O ==> set operating system to 'os'
4194 -T ==> set image type to 'type'
4195 -C ==> set compression type 'comp'
4196 -a ==> set load address to 'addr' (hex)
4197 -e ==> set entry point to 'ep' (hex)
4198 -n ==> set image name to 'name'
4199 -d ==> use image data from 'datafile'
wdenk24ee89b2002-11-03 17:56:27 +00004200
wdenk69459792004-05-29 16:53:29 +00004201Right now, all Linux kernels for PowerPC systems use the same load
4202address (0x00000000), but the entry point address depends on the
4203kernel version:
wdenkc6097192002-11-03 00:24:07 +00004204
wdenk2729af92004-05-03 20:45:30 +00004205- 2.2.x kernels have the entry point at 0x0000000C,
4206- 2.3.x and later kernels have the entry point at 0x00000000.
wdenkc6097192002-11-03 00:24:07 +00004207
wdenk2729af92004-05-03 20:45:30 +00004208So a typical call to build a U-Boot image would read:
wdenkc6097192002-11-03 00:24:07 +00004209
wdenk2729af92004-05-03 20:45:30 +00004210 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
4211 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
Stefan Roesea47a12b2010-04-15 16:07:28 +02004212 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \
wdenk2729af92004-05-03 20:45:30 +00004213 > examples/uImage.TQM850L
4214 Image Name: 2.4.4 kernel for TQM850L
4215 Created: Wed Jul 19 02:34:59 2000
4216 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4217 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
4218 Load Address: 0x00000000
4219 Entry Point: 0x00000000
wdenkc6097192002-11-03 00:24:07 +00004220
wdenk2729af92004-05-03 20:45:30 +00004221To verify the contents of the image (or check for corruption):
wdenkc6097192002-11-03 00:24:07 +00004222
wdenk2729af92004-05-03 20:45:30 +00004223 -> tools/mkimage -l examples/uImage.TQM850L
4224 Image Name: 2.4.4 kernel for TQM850L
4225 Created: Wed Jul 19 02:34:59 2000
4226 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4227 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
4228 Load Address: 0x00000000
4229 Entry Point: 0x00000000
wdenkc6097192002-11-03 00:24:07 +00004230
wdenk2729af92004-05-03 20:45:30 +00004231NOTE: for embedded systems where boot time is critical you can trade
4232speed for memory and install an UNCOMPRESSED image instead: this
4233needs more space in Flash, but boots much faster since it does not
4234need to be uncompressed:
wdenkc6097192002-11-03 00:24:07 +00004235
Stefan Roesea47a12b2010-04-15 16:07:28 +02004236 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz
wdenk2729af92004-05-03 20:45:30 +00004237 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
4238 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
Stefan Roesea47a12b2010-04-15 16:07:28 +02004239 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \
wdenk2729af92004-05-03 20:45:30 +00004240 > examples/uImage.TQM850L-uncompressed
4241 Image Name: 2.4.4 kernel for TQM850L
4242 Created: Wed Jul 19 02:34:59 2000
4243 Image Type: PowerPC Linux Kernel Image (uncompressed)
4244 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
4245 Load Address: 0x00000000
4246 Entry Point: 0x00000000
wdenkc6097192002-11-03 00:24:07 +00004247
wdenkc6097192002-11-03 00:24:07 +00004248
wdenk2729af92004-05-03 20:45:30 +00004249Similar you can build U-Boot images from a 'ramdisk.image.gz' file
4250when your kernel is intended to use an initial ramdisk:
wdenkdb01a2e2004-04-15 23:14:49 +00004251
wdenk2729af92004-05-03 20:45:30 +00004252 -> tools/mkimage -n 'Simple Ramdisk Image' \
4253 > -A ppc -O linux -T ramdisk -C gzip \
4254 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
4255 Image Name: Simple Ramdisk Image
4256 Created: Wed Jan 12 14:01:50 2000
4257 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
4258 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
4259 Load Address: 0x00000000
4260 Entry Point: 0x00000000
wdenkdb01a2e2004-04-15 23:14:49 +00004261
Guilherme Maciel Ferreiraa804b5c2013-12-01 12:43:11 -07004262The "dumpimage" is a tool to disassemble images built by mkimage. Its "-i"
4263option performs the converse operation of the mkimage's second form (the "-d"
4264option). Given an image built by mkimage, the dumpimage extracts a "data file"
4265from the image:
4266
Guilherme Maciel Ferreiraf41f5b72015-01-15 02:54:40 -02004267 tools/dumpimage -i image -T type -p position data_file
4268 -i ==> extract from the 'image' a specific 'data_file'
4269 -T ==> set image type to 'type'
4270 -p ==> 'position' (starting at 0) of the 'data_file' inside the 'image'
Guilherme Maciel Ferreiraa804b5c2013-12-01 12:43:11 -07004271
wdenkdb01a2e2004-04-15 23:14:49 +00004272
wdenk2729af92004-05-03 20:45:30 +00004273Installing a Linux Image:
4274-------------------------
wdenkdb01a2e2004-04-15 23:14:49 +00004275
wdenk2729af92004-05-03 20:45:30 +00004276To downloading a U-Boot image over the serial (console) interface,
4277you must convert the image to S-Record format:
wdenkdb01a2e2004-04-15 23:14:49 +00004278
wdenk2729af92004-05-03 20:45:30 +00004279 objcopy -I binary -O srec examples/image examples/image.srec
wdenkdb01a2e2004-04-15 23:14:49 +00004280
wdenk2729af92004-05-03 20:45:30 +00004281The 'objcopy' does not understand the information in the U-Boot
4282image header, so the resulting S-Record file will be relative to
4283address 0x00000000. To load it to a given address, you need to
4284specify the target address as 'offset' parameter with the 'loads'
4285command.
wdenkc6097192002-11-03 00:24:07 +00004286
wdenk2729af92004-05-03 20:45:30 +00004287Example: install the image to address 0x40100000 (which on the
4288TQM8xxL is in the first Flash bank):
wdenkc6097192002-11-03 00:24:07 +00004289
wdenk2729af92004-05-03 20:45:30 +00004290 => erase 40100000 401FFFFF
wdenkc6097192002-11-03 00:24:07 +00004291
wdenk2729af92004-05-03 20:45:30 +00004292 .......... done
4293 Erased 8 sectors
wdenkc6097192002-11-03 00:24:07 +00004294
wdenk2729af92004-05-03 20:45:30 +00004295 => loads 40100000
4296 ## Ready for S-Record download ...
4297 ~>examples/image.srec
4298 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
4299 ...
4300 15989 15990 15991 15992
4301 [file transfer complete]
4302 [connected]
4303 ## Start Addr = 0x00000000
wdenkc6097192002-11-03 00:24:07 +00004304
4305
wdenk2729af92004-05-03 20:45:30 +00004306You can check the success of the download using the 'iminfo' command;
Wolfgang Denk218ca722008-03-26 10:40:12 +01004307this includes a checksum verification so you can be sure no data
wdenk2729af92004-05-03 20:45:30 +00004308corruption happened:
wdenkc6097192002-11-03 00:24:07 +00004309
wdenk2729af92004-05-03 20:45:30 +00004310 => imi 40100000
wdenkc6097192002-11-03 00:24:07 +00004311
wdenk2729af92004-05-03 20:45:30 +00004312 ## Checking Image at 40100000 ...
4313 Image Name: 2.2.13 for initrd on TQM850L
4314 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4315 Data Size: 335725 Bytes = 327 kB = 0 MB
4316 Load Address: 00000000
4317 Entry Point: 0000000c
4318 Verifying Checksum ... OK
wdenkc6097192002-11-03 00:24:07 +00004319
4320
wdenk2729af92004-05-03 20:45:30 +00004321Boot Linux:
4322-----------
wdenkc6097192002-11-03 00:24:07 +00004323
wdenk2729af92004-05-03 20:45:30 +00004324The "bootm" command is used to boot an application that is stored in
4325memory (RAM or Flash). In case of a Linux kernel image, the contents
4326of the "bootargs" environment variable is passed to the kernel as
4327parameters. You can check and modify this variable using the
4328"printenv" and "setenv" commands:
wdenkc6097192002-11-03 00:24:07 +00004329
4330
wdenk2729af92004-05-03 20:45:30 +00004331 => printenv bootargs
4332 bootargs=root=/dev/ram
wdenkc6097192002-11-03 00:24:07 +00004333
wdenk2729af92004-05-03 20:45:30 +00004334 => 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 +00004335
wdenk2729af92004-05-03 20:45:30 +00004336 => printenv bootargs
4337 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 +00004338
wdenk2729af92004-05-03 20:45:30 +00004339 => bootm 40020000
4340 ## Booting Linux kernel at 40020000 ...
4341 Image Name: 2.2.13 for NFS on TQM850L
4342 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4343 Data Size: 381681 Bytes = 372 kB = 0 MB
4344 Load Address: 00000000
4345 Entry Point: 0000000c
4346 Verifying Checksum ... OK
4347 Uncompressing Kernel Image ... OK
4348 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
4349 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
4350 time_init: decrementer frequency = 187500000/60
4351 Calibrating delay loop... 49.77 BogoMIPS
4352 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
4353 ...
wdenkc6097192002-11-03 00:24:07 +00004354
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02004355If you want to boot a Linux kernel with initial RAM disk, you pass
wdenk2729af92004-05-03 20:45:30 +00004356the memory addresses of both the kernel and the initrd image (PPBCOOT
4357format!) to the "bootm" command:
wdenkc6097192002-11-03 00:24:07 +00004358
wdenk2729af92004-05-03 20:45:30 +00004359 => imi 40100000 40200000
wdenkc6097192002-11-03 00:24:07 +00004360
wdenk2729af92004-05-03 20:45:30 +00004361 ## Checking Image at 40100000 ...
4362 Image Name: 2.2.13 for initrd on TQM850L
4363 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4364 Data Size: 335725 Bytes = 327 kB = 0 MB
4365 Load Address: 00000000
4366 Entry Point: 0000000c
4367 Verifying Checksum ... OK
wdenkc6097192002-11-03 00:24:07 +00004368
wdenk2729af92004-05-03 20:45:30 +00004369 ## Checking Image at 40200000 ...
4370 Image Name: Simple Ramdisk Image
4371 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
4372 Data Size: 566530 Bytes = 553 kB = 0 MB
4373 Load Address: 00000000
4374 Entry Point: 00000000
4375 Verifying Checksum ... OK
wdenkc6097192002-11-03 00:24:07 +00004376
wdenk2729af92004-05-03 20:45:30 +00004377 => bootm 40100000 40200000
4378 ## Booting Linux kernel at 40100000 ...
4379 Image Name: 2.2.13 for initrd on TQM850L
4380 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4381 Data Size: 335725 Bytes = 327 kB = 0 MB
4382 Load Address: 00000000
4383 Entry Point: 0000000c
4384 Verifying Checksum ... OK
4385 Uncompressing Kernel Image ... OK
4386 ## Loading RAMDisk Image at 40200000 ...
4387 Image Name: Simple Ramdisk Image
4388 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
4389 Data Size: 566530 Bytes = 553 kB = 0 MB
4390 Load Address: 00000000
4391 Entry Point: 00000000
4392 Verifying Checksum ... OK
4393 Loading Ramdisk ... OK
4394 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
4395 Boot arguments: root=/dev/ram
4396 time_init: decrementer frequency = 187500000/60
4397 Calibrating delay loop... 49.77 BogoMIPS
4398 ...
4399 RAMDISK: Compressed image found at block 0
4400 VFS: Mounted root (ext2 filesystem).
wdenkc6097192002-11-03 00:24:07 +00004401
wdenk2729af92004-05-03 20:45:30 +00004402 bash#
wdenkc6097192002-11-03 00:24:07 +00004403
Matthew McClintock02677682006-06-28 10:41:37 -05004404Boot Linux and pass a flat device tree:
4405-----------
4406
4407First, U-Boot must be compiled with the appropriate defines. See the section
4408titled "Linux Kernel Interface" above for a more in depth explanation. The
4409following is an example of how to start a kernel and pass an updated
4410flat device tree:
4411
4412=> print oftaddr
4413oftaddr=0x300000
4414=> print oft
4415oft=oftrees/mpc8540ads.dtb
4416=> tftp $oftaddr $oft
4417Speed: 1000, full duplex
4418Using TSEC0 device
4419TFTP from server 192.168.1.1; our IP address is 192.168.1.101
4420Filename 'oftrees/mpc8540ads.dtb'.
4421Load address: 0x300000
4422Loading: #
4423done
4424Bytes transferred = 4106 (100a hex)
4425=> tftp $loadaddr $bootfile
4426Speed: 1000, full duplex
4427Using TSEC0 device
4428TFTP from server 192.168.1.1; our IP address is 192.168.1.2
4429Filename 'uImage'.
4430Load address: 0x200000
4431Loading:############
4432done
4433Bytes transferred = 1029407 (fb51f hex)
4434=> print loadaddr
4435loadaddr=200000
4436=> print oftaddr
4437oftaddr=0x300000
4438=> bootm $loadaddr - $oftaddr
4439## Booting image at 00200000 ...
Wolfgang Denka9398e02006-11-27 15:32:42 +01004440 Image Name: Linux-2.6.17-dirty
4441 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4442 Data Size: 1029343 Bytes = 1005.2 kB
Matthew McClintock02677682006-06-28 10:41:37 -05004443 Load Address: 00000000
Wolfgang Denka9398e02006-11-27 15:32:42 +01004444 Entry Point: 00000000
Matthew McClintock02677682006-06-28 10:41:37 -05004445 Verifying Checksum ... OK
4446 Uncompressing Kernel Image ... OK
4447Booting using flat device tree at 0x300000
4448Using MPC85xx ADS machine description
4449Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb
4450[snip]
4451
4452
wdenk2729af92004-05-03 20:45:30 +00004453More About U-Boot Image Types:
4454------------------------------
wdenk6069ff22003-02-28 00:49:47 +00004455
wdenk2729af92004-05-03 20:45:30 +00004456U-Boot supports the following image types:
wdenk6069ff22003-02-28 00:49:47 +00004457
wdenk2729af92004-05-03 20:45:30 +00004458 "Standalone Programs" are directly runnable in the environment
4459 provided by U-Boot; it is expected that (if they behave
4460 well) you can continue to work in U-Boot after return from
4461 the Standalone Program.
4462 "OS Kernel Images" are usually images of some Embedded OS which
4463 will take over control completely. Usually these programs
4464 will install their own set of exception handlers, device
4465 drivers, set up the MMU, etc. - this means, that you cannot
4466 expect to re-enter U-Boot except by resetting the CPU.
4467 "RAMDisk Images" are more or less just data blocks, and their
4468 parameters (address, size) are passed to an OS kernel that is
4469 being started.
4470 "Multi-File Images" contain several images, typically an OS
4471 (Linux) kernel image and one or more data images like
4472 RAMDisks. This construct is useful for instance when you want
4473 to boot over the network using BOOTP etc., where the boot
4474 server provides just a single image file, but you want to get
4475 for instance an OS kernel and a RAMDisk image.
stroesec1551ea2003-04-04 15:53:41 +00004476
wdenk2729af92004-05-03 20:45:30 +00004477 "Multi-File Images" start with a list of image sizes, each
4478 image size (in bytes) specified by an "uint32_t" in network
4479 byte order. This list is terminated by an "(uint32_t)0".
4480 Immediately after the terminating 0 follow the images, one by
4481 one, all aligned on "uint32_t" boundaries (size rounded up to
4482 a multiple of 4 bytes).
stroesec1551ea2003-04-04 15:53:41 +00004483
wdenk2729af92004-05-03 20:45:30 +00004484 "Firmware Images" are binary images containing firmware (like
4485 U-Boot or FPGA images) which usually will be programmed to
4486 flash memory.
stroesec1551ea2003-04-04 15:53:41 +00004487
wdenk2729af92004-05-03 20:45:30 +00004488 "Script files" are command sequences that will be executed by
4489 U-Boot's command interpreter; this feature is especially
4490 useful when you configure U-Boot to use a real shell (hush)
4491 as command interpreter.
wdenk6069ff22003-02-28 00:49:47 +00004492
Marek Vasut44f074c2012-03-14 21:52:45 +00004493Booting the Linux zImage:
4494-------------------------
4495
4496On some platforms, it's possible to boot Linux zImage. This is done
4497using the "bootz" command. The syntax of "bootz" command is the same
4498as the syntax of "bootm" command.
4499
Tom Rini8ac28562013-05-16 11:40:11 -04004500Note, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply
Marek Vasut017e1f32012-03-18 11:47:58 +00004501kernel with raw initrd images. The syntax is slightly different, the
4502address of the initrd must be augmented by it's size, in the following
4503format: "<initrd addres>:<initrd size>".
4504
wdenkc6097192002-11-03 00:24:07 +00004505
wdenk2729af92004-05-03 20:45:30 +00004506Standalone HOWTO:
4507=================
wdenkc6097192002-11-03 00:24:07 +00004508
wdenk2729af92004-05-03 20:45:30 +00004509One of the features of U-Boot is that you can dynamically load and
4510run "standalone" applications, which can use some resources of
4511U-Boot like console I/O functions or interrupt services.
wdenkc6097192002-11-03 00:24:07 +00004512
wdenk2729af92004-05-03 20:45:30 +00004513Two simple examples are included with the sources:
wdenkc6097192002-11-03 00:24:07 +00004514
wdenk2729af92004-05-03 20:45:30 +00004515"Hello World" Demo:
4516-------------------
wdenkc6097192002-11-03 00:24:07 +00004517
wdenk2729af92004-05-03 20:45:30 +00004518'examples/hello_world.c' contains a small "Hello World" Demo
4519application; it is automatically compiled when you build U-Boot.
4520It's configured to run at address 0x00040004, so you can play with it
4521like that:
wdenkc6097192002-11-03 00:24:07 +00004522
wdenk2729af92004-05-03 20:45:30 +00004523 => loads
4524 ## Ready for S-Record download ...
4525 ~>examples/hello_world.srec
4526 1 2 3 4 5 6 7 8 9 10 11 ...
4527 [file transfer complete]
4528 [connected]
4529 ## Start Addr = 0x00040004
wdenkc6097192002-11-03 00:24:07 +00004530
wdenk2729af92004-05-03 20:45:30 +00004531 => go 40004 Hello World! This is a test.
4532 ## Starting application at 0x00040004 ...
4533 Hello World
4534 argc = 7
4535 argv[0] = "40004"
4536 argv[1] = "Hello"
4537 argv[2] = "World!"
4538 argv[3] = "This"
4539 argv[4] = "is"
4540 argv[5] = "a"
4541 argv[6] = "test."
4542 argv[7] = "<NULL>"
4543 Hit any key to exit ...
wdenkc6097192002-11-03 00:24:07 +00004544
wdenk2729af92004-05-03 20:45:30 +00004545 ## Application terminated, rc = 0x0
wdenkc6097192002-11-03 00:24:07 +00004546
wdenk2729af92004-05-03 20:45:30 +00004547Another example, which demonstrates how to register a CPM interrupt
4548handler with the U-Boot code, can be found in 'examples/timer.c'.
4549Here, a CPM timer is set up to generate an interrupt every second.
4550The interrupt service routine is trivial, just printing a '.'
4551character, but this is just a demo program. The application can be
4552controlled by the following keys:
wdenkc6097192002-11-03 00:24:07 +00004553
wdenk2729af92004-05-03 20:45:30 +00004554 ? - print current values og the CPM Timer registers
4555 b - enable interrupts and start timer
4556 e - stop timer and disable interrupts
4557 q - quit application
wdenkc6097192002-11-03 00:24:07 +00004558
wdenk2729af92004-05-03 20:45:30 +00004559 => loads
4560 ## Ready for S-Record download ...
4561 ~>examples/timer.srec
4562 1 2 3 4 5 6 7 8 9 10 11 ...
4563 [file transfer complete]
4564 [connected]
4565 ## Start Addr = 0x00040004
wdenkc6097192002-11-03 00:24:07 +00004566
wdenk2729af92004-05-03 20:45:30 +00004567 => go 40004
4568 ## Starting application at 0x00040004 ...
4569 TIMERS=0xfff00980
4570 Using timer 1
4571 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
wdenkc6097192002-11-03 00:24:07 +00004572
wdenk2729af92004-05-03 20:45:30 +00004573Hit 'b':
4574 [q, b, e, ?] Set interval 1000000 us
4575 Enabling timer
4576Hit '?':
4577 [q, b, e, ?] ........
4578 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
4579Hit '?':
4580 [q, b, e, ?] .
4581 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
4582Hit '?':
4583 [q, b, e, ?] .
4584 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
4585Hit '?':
4586 [q, b, e, ?] .
4587 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
4588Hit 'e':
4589 [q, b, e, ?] ...Stopping timer
4590Hit 'q':
4591 [q, b, e, ?] ## Application terminated, rc = 0x0
wdenkc6097192002-11-03 00:24:07 +00004592
4593
wdenk2729af92004-05-03 20:45:30 +00004594Minicom warning:
4595================
wdenk85ec0bc2003-03-31 16:34:49 +00004596
wdenk2729af92004-05-03 20:45:30 +00004597Over time, many people have reported problems when trying to use the
4598"minicom" terminal emulation program for serial download. I (wd)
4599consider minicom to be broken, and recommend not to use it. Under
4600Unix, I recommend to use C-Kermit for general purpose use (and
4601especially for kermit binary protocol download ("loadb" command), and
Karl O. Pince53515a2012-10-01 05:11:56 +00004602use "cu" for S-Record download ("loads" command). See
4603http://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3.
4604for help with kermit.
4605
wdenk85ec0bc2003-03-31 16:34:49 +00004606
wdenk2729af92004-05-03 20:45:30 +00004607Nevertheless, if you absolutely want to use it try adding this
4608configuration to your "File transfer protocols" section:
wdenk52f52c12003-06-19 23:04:19 +00004609
wdenk2729af92004-05-03 20:45:30 +00004610 Name Program Name U/D FullScr IO-Red. Multi
4611 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
4612 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
wdenk52f52c12003-06-19 23:04:19 +00004613
4614
wdenk2729af92004-05-03 20:45:30 +00004615NetBSD Notes:
4616=============
wdenkc6097192002-11-03 00:24:07 +00004617
wdenk2729af92004-05-03 20:45:30 +00004618Starting at version 0.9.2, U-Boot supports NetBSD both as host
4619(build U-Boot) and target system (boots NetBSD/mpc8xx).
wdenkc6097192002-11-03 00:24:07 +00004620
wdenk2729af92004-05-03 20:45:30 +00004621Building requires a cross environment; it is known to work on
4622NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
4623need gmake since the Makefiles are not compatible with BSD make).
4624Note that the cross-powerpc package does not install include files;
4625attempting to build U-Boot will fail because <machine/ansi.h> is
4626missing. This file has to be installed and patched manually:
wdenkc6097192002-11-03 00:24:07 +00004627
wdenk2729af92004-05-03 20:45:30 +00004628 # cd /usr/pkg/cross/powerpc-netbsd/include
4629 # mkdir powerpc
4630 # ln -s powerpc machine
4631 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
4632 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
wdenkc6097192002-11-03 00:24:07 +00004633
wdenk2729af92004-05-03 20:45:30 +00004634Native builds *don't* work due to incompatibilities between native
4635and U-Boot include files.
wdenkc6097192002-11-03 00:24:07 +00004636
wdenk2729af92004-05-03 20:45:30 +00004637Booting assumes that (the first part of) the image booted is a
4638stage-2 loader which in turn loads and then invokes the kernel
4639proper. Loader sources will eventually appear in the NetBSD source
4640tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
wdenk2a8af182005-04-13 10:02:42 +00004641meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
wdenkc6097192002-11-03 00:24:07 +00004642
4643
wdenk2729af92004-05-03 20:45:30 +00004644Implementation Internals:
4645=========================
wdenkc6097192002-11-03 00:24:07 +00004646
wdenk2729af92004-05-03 20:45:30 +00004647The following is not intended to be a complete description of every
4648implementation detail. However, it should help to understand the
4649inner workings of U-Boot and make it easier to port it to custom
4650hardware.
wdenkc6097192002-11-03 00:24:07 +00004651
4652
wdenk2729af92004-05-03 20:45:30 +00004653Initial Stack, Global Data:
4654---------------------------
wdenkc6097192002-11-03 00:24:07 +00004655
wdenk2729af92004-05-03 20:45:30 +00004656The implementation of U-Boot is complicated by the fact that U-Boot
4657starts running out of ROM (flash memory), usually without access to
4658system RAM (because the memory controller is not initialized yet).
4659This means that we don't have writable Data or BSS segments, and BSS
4660is not initialized as zero. To be able to get a C environment working
4661at all, we have to allocate at least a minimal stack. Implementation
4662options for this are defined and restricted by the CPU used: Some CPU
4663models provide on-chip memory (like the IMMR area on MPC8xx and
4664MPC826x processors), on others (parts of) the data cache can be
4665locked as (mis-) used as memory, etc.
wdenkc6097192002-11-03 00:24:07 +00004666
Wolfgang Denk218ca722008-03-26 10:40:12 +01004667 Chris Hallinan posted a good summary of these issues to the
Wolfgang Denk06682362008-12-30 22:56:11 +01004668 U-Boot mailing list:
wdenk43d96162003-03-06 00:02:04 +00004669
wdenk2729af92004-05-03 20:45:30 +00004670 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
4671 From: "Chris Hallinan" <clh@net1plus.com>
4672 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
4673 ...
wdenk43d96162003-03-06 00:02:04 +00004674
wdenk2729af92004-05-03 20:45:30 +00004675 Correct me if I'm wrong, folks, but the way I understand it
4676 is this: Using DCACHE as initial RAM for Stack, etc, does not
4677 require any physical RAM backing up the cache. The cleverness
4678 is that the cache is being used as a temporary supply of
4679 necessary storage before the SDRAM controller is setup. It's
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02004680 beyond the scope of this list to explain the details, but you
wdenk2729af92004-05-03 20:45:30 +00004681 can see how this works by studying the cache architecture and
4682 operation in the architecture and processor-specific manuals.
wdenk43d96162003-03-06 00:02:04 +00004683
wdenk2729af92004-05-03 20:45:30 +00004684 OCM is On Chip Memory, which I believe the 405GP has 4K. It
4685 is another option for the system designer to use as an
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02004686 initial stack/RAM area prior to SDRAM being available. Either
wdenk2729af92004-05-03 20:45:30 +00004687 option should work for you. Using CS 4 should be fine if your
4688 board designers haven't used it for something that would
4689 cause you grief during the initial boot! It is frequently not
4690 used.
wdenk43d96162003-03-06 00:02:04 +00004691
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02004692 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere
wdenk2729af92004-05-03 20:45:30 +00004693 with your processor/board/system design. The default value
4694 you will find in any recent u-boot distribution in
Stefan Roese8a316c92005-08-01 16:49:12 +02004695 walnut.h should work for you. I'd set it to a value larger
wdenk2729af92004-05-03 20:45:30 +00004696 than your SDRAM module. If you have a 64MB SDRAM module, set
4697 it above 400_0000. Just make sure your board has no resources
4698 that are supposed to respond to that address! That code in
4699 start.S has been around a while and should work as is when
4700 you get the config right.
wdenk43d96162003-03-06 00:02:04 +00004701
wdenk2729af92004-05-03 20:45:30 +00004702 -Chris Hallinan
4703 DS4.COM, Inc.
wdenk43d96162003-03-06 00:02:04 +00004704
wdenk2729af92004-05-03 20:45:30 +00004705It is essential to remember this, since it has some impact on the C
4706code for the initialization procedures:
wdenkc6097192002-11-03 00:24:07 +00004707
wdenk2729af92004-05-03 20:45:30 +00004708* Initialized global data (data segment) is read-only. Do not attempt
4709 to write it.
wdenkc6097192002-11-03 00:24:07 +00004710
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08004711* Do not use any uninitialized global data (or implicitly initialized
wdenk2729af92004-05-03 20:45:30 +00004712 as zero data - BSS segment) at all - this is undefined, initiali-
4713 zation is performed later (when relocating to RAM).
wdenkc6097192002-11-03 00:24:07 +00004714
wdenk2729af92004-05-03 20:45:30 +00004715* Stack space is very limited. Avoid big data buffers or things like
4716 that.
wdenkc6097192002-11-03 00:24:07 +00004717
wdenk2729af92004-05-03 20:45:30 +00004718Having only the stack as writable memory limits means we cannot use
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08004719normal global data to share information between the code. But it
wdenk2729af92004-05-03 20:45:30 +00004720turned out that the implementation of U-Boot can be greatly
4721simplified by making a global data structure (gd_t) available to all
4722functions. We could pass a pointer to this data as argument to _all_
4723functions, but this would bloat the code. Instead we use a feature of
4724the GCC compiler (Global Register Variables) to share the data: we
4725place a pointer (gd) to the global data into a register which we
4726reserve for this purpose.
wdenkc6097192002-11-03 00:24:07 +00004727
wdenk2729af92004-05-03 20:45:30 +00004728When choosing a register for such a purpose we are restricted by the
4729relevant (E)ABI specifications for the current architecture, and by
4730GCC's implementation.
wdenkc6097192002-11-03 00:24:07 +00004731
wdenk2729af92004-05-03 20:45:30 +00004732For PowerPC, the following registers have specific use:
4733 R1: stack pointer
Wolfgang Denke7670f62008-02-14 22:43:22 +01004734 R2: reserved for system use
wdenk2729af92004-05-03 20:45:30 +00004735 R3-R4: parameter passing and return values
4736 R5-R10: parameter passing
4737 R13: small data area pointer
4738 R30: GOT pointer
4739 R31: frame pointer
wdenkc6097192002-11-03 00:24:07 +00004740
Joakim Tjernlunde6bee802010-01-19 14:41:58 +01004741 (U-Boot also uses R12 as internal GOT pointer. r12
4742 is a volatile register so r12 needs to be reset when
4743 going back and forth between asm and C)
wdenkc6097192002-11-03 00:24:07 +00004744
Wolfgang Denke7670f62008-02-14 22:43:22 +01004745 ==> U-Boot will use R2 to hold a pointer to the global data
wdenkc6097192002-11-03 00:24:07 +00004746
wdenk2729af92004-05-03 20:45:30 +00004747 Note: on PPC, we could use a static initializer (since the
4748 address of the global data structure is known at compile time),
4749 but it turned out that reserving a register results in somewhat
4750 smaller code - although the code savings are not that big (on
4751 average for all boards 752 bytes for the whole U-Boot image,
4752 624 text + 127 data).
wdenkc6097192002-11-03 00:24:07 +00004753
wdenk2729af92004-05-03 20:45:30 +00004754On ARM, the following registers are used:
wdenkc6097192002-11-03 00:24:07 +00004755
wdenk2729af92004-05-03 20:45:30 +00004756 R0: function argument word/integer result
4757 R1-R3: function argument word
Jeroen Hofstee12eba1b2013-09-21 14:04:42 +02004758 R9: platform specific
4759 R10: stack limit (used only if stack checking is enabled)
wdenk2729af92004-05-03 20:45:30 +00004760 R11: argument (frame) pointer
4761 R12: temporary workspace
4762 R13: stack pointer
4763 R14: link register
4764 R15: program counter
wdenkc6097192002-11-03 00:24:07 +00004765
Jeroen Hofstee12eba1b2013-09-21 14:04:42 +02004766 ==> U-Boot will use R9 to hold a pointer to the global data
4767
4768 Note: on ARM, only R_ARM_RELATIVE relocations are supported.
wdenkc6097192002-11-03 00:24:07 +00004769
Thomas Chou0df01fd2010-05-21 11:08:03 +08004770On Nios II, the ABI is documented here:
4771 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf
4772
4773 ==> U-Boot will use gp to hold a pointer to the global data
4774
4775 Note: on Nios II, we give "-G0" option to gcc and don't use gp
4776 to access small data sections, so gp is free.
4777
Macpaul Linafc1ce82011-10-19 20:41:11 +00004778On NDS32, the following registers are used:
4779
4780 R0-R1: argument/return
4781 R2-R5: argument
4782 R15: temporary register for assembler
4783 R16: trampoline register
4784 R28: frame pointer (FP)
4785 R29: global pointer (GP)
4786 R30: link register (LP)
4787 R31: stack pointer (SP)
4788 PC: program counter (PC)
4789
4790 ==> U-Boot will use R10 to hold a pointer to the global data
4791
Wolfgang Denkd87080b2006-03-31 18:32:53 +02004792NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
4793or current versions of GCC may "optimize" the code too much.
wdenkc6097192002-11-03 00:24:07 +00004794
Rick Chen3fafced2017-12-26 13:55:59 +08004795On RISC-V, the following registers are used:
4796
4797 x0: hard-wired zero (zero)
4798 x1: return address (ra)
4799 x2: stack pointer (sp)
4800 x3: global pointer (gp)
4801 x4: thread pointer (tp)
4802 x5: link register (t0)
4803 x8: frame pointer (fp)
4804 x10-x11: arguments/return values (a0-1)
4805 x12-x17: arguments (a2-7)
4806 x28-31: temporaries (t3-6)
4807 pc: program counter (pc)
4808
4809 ==> U-Boot will use gp to hold a pointer to the global data
4810
wdenk2729af92004-05-03 20:45:30 +00004811Memory Management:
4812------------------
wdenkc6097192002-11-03 00:24:07 +00004813
wdenk2729af92004-05-03 20:45:30 +00004814U-Boot runs in system state and uses physical addresses, i.e. the
4815MMU is not used either for address mapping nor for memory protection.
wdenkc6097192002-11-03 00:24:07 +00004816
wdenk2729af92004-05-03 20:45:30 +00004817The available memory is mapped to fixed addresses using the memory
4818controller. In this process, a contiguous block is formed for each
4819memory type (Flash, SDRAM, SRAM), even when it consists of several
4820physical memory banks.
wdenkc6097192002-11-03 00:24:07 +00004821
wdenk2729af92004-05-03 20:45:30 +00004822U-Boot is installed in the first 128 kB of the first Flash bank (on
4823TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
4824booting and sizing and initializing DRAM, the code relocates itself
4825to the upper end of DRAM. Immediately below the U-Boot code some
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02004826memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN
wdenk2729af92004-05-03 20:45:30 +00004827configuration setting]. Below that, a structure with global Board
4828Info data is placed, followed by the stack (growing downward).
wdenkc6097192002-11-03 00:24:07 +00004829
wdenk2729af92004-05-03 20:45:30 +00004830Additionally, some exception handler code is copied to the low 8 kB
4831of DRAM (0x00000000 ... 0x00001FFF).
wdenkc6097192002-11-03 00:24:07 +00004832
wdenk2729af92004-05-03 20:45:30 +00004833So a typical memory configuration with 16 MB of DRAM could look like
4834this:
wdenkc6097192002-11-03 00:24:07 +00004835
wdenk2729af92004-05-03 20:45:30 +00004836 0x0000 0000 Exception Vector code
4837 :
4838 0x0000 1FFF
4839 0x0000 2000 Free for Application Use
4840 :
4841 :
wdenkc6097192002-11-03 00:24:07 +00004842
wdenk2729af92004-05-03 20:45:30 +00004843 :
4844 :
4845 0x00FB FF20 Monitor Stack (Growing downward)
4846 0x00FB FFAC Board Info Data and permanent copy of global data
4847 0x00FC 0000 Malloc Arena
4848 :
4849 0x00FD FFFF
4850 0x00FE 0000 RAM Copy of Monitor Code
4851 ... eventually: LCD or video framebuffer
4852 ... eventually: pRAM (Protected RAM - unchanged by reset)
4853 0x00FF FFFF [End of RAM]
wdenkc6097192002-11-03 00:24:07 +00004854
4855
wdenk2729af92004-05-03 20:45:30 +00004856System Initialization:
4857----------------------
wdenkc6097192002-11-03 00:24:07 +00004858
wdenk2729af92004-05-03 20:45:30 +00004859In the reset configuration, U-Boot starts at the reset entry point
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02004860(on most PowerPC systems at address 0x00000100). Because of the reset
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08004861configuration for CS0# this is a mirror of the on board Flash memory.
wdenk2729af92004-05-03 20:45:30 +00004862To be able to re-map memory U-Boot then jumps to its link address.
4863To be able to implement the initialization code in C, a (small!)
4864initial stack is set up in the internal Dual Ported RAM (in case CPUs
Heiko Schocher2eb48ff2017-06-07 17:33:10 +02004865which provide such a feature like), or in a locked part of the data
4866cache. After that, U-Boot initializes the CPU core, the caches and
4867the SIU.
wdenkc6097192002-11-03 00:24:07 +00004868
wdenk2729af92004-05-03 20:45:30 +00004869Next, all (potentially) available memory banks are mapped using a
4870preliminary mapping. For example, we put them on 512 MB boundaries
4871(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
4872on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
4873programmed for SDRAM access. Using the temporary configuration, a
4874simple memory test is run that determines the size of the SDRAM
4875banks.
wdenkc6097192002-11-03 00:24:07 +00004876
wdenk2729af92004-05-03 20:45:30 +00004877When there is more than one SDRAM bank, and the banks are of
4878different size, the largest is mapped first. For equal size, the first
4879bank (CS2#) is mapped first. The first mapping is always for address
48800x00000000, with any additional banks following immediately to create
4881contiguous memory starting from 0.
wdenkc6097192002-11-03 00:24:07 +00004882
wdenk2729af92004-05-03 20:45:30 +00004883Then, the monitor installs itself at the upper end of the SDRAM area
4884and allocates memory for use by malloc() and for the global Board
4885Info data; also, the exception vector code is copied to the low RAM
4886pages, and the final stack is set up.
wdenkc6097192002-11-03 00:24:07 +00004887
wdenk2729af92004-05-03 20:45:30 +00004888Only after this relocation will you have a "normal" C environment;
4889until that you are restricted in several ways, mostly because you are
4890running from ROM, and because the code will have to be relocated to a
4891new address in RAM.
wdenkc6097192002-11-03 00:24:07 +00004892
4893
wdenk2729af92004-05-03 20:45:30 +00004894U-Boot Porting Guide:
4895----------------------
wdenkc6097192002-11-03 00:24:07 +00004896
wdenk2729af92004-05-03 20:45:30 +00004897[Based on messages by Jerry Van Baren in the U-Boot-Users mailing
4898list, October 2002]
wdenkc6097192002-11-03 00:24:07 +00004899
4900
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04004901int main(int argc, char *argv[])
wdenk2729af92004-05-03 20:45:30 +00004902{
4903 sighandler_t no_more_time;
wdenkc6097192002-11-03 00:24:07 +00004904
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04004905 signal(SIGALRM, no_more_time);
4906 alarm(PROJECT_DEADLINE - toSec (3 * WEEK));
wdenkc6097192002-11-03 00:24:07 +00004907
wdenk2729af92004-05-03 20:45:30 +00004908 if (available_money > available_manpower) {
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04004909 Pay consultant to port U-Boot;
wdenkc6097192002-11-03 00:24:07 +00004910 return 0;
4911 }
4912
wdenk2729af92004-05-03 20:45:30 +00004913 Download latest U-Boot source;
4914
Wolfgang Denk06682362008-12-30 22:56:11 +01004915 Subscribe to u-boot mailing list;
wdenk2729af92004-05-03 20:45:30 +00004916
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04004917 if (clueless)
4918 email("Hi, I am new to U-Boot, how do I get started?");
wdenkc6097192002-11-03 00:24:07 +00004919
wdenk2729af92004-05-03 20:45:30 +00004920 while (learning) {
4921 Read the README file in the top level directory;
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04004922 Read http://www.denx.de/twiki/bin/view/DULG/Manual;
4923 Read applicable doc/*.README;
wdenk2729af92004-05-03 20:45:30 +00004924 Read the source, Luke;
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04004925 /* find . -name "*.[chS]" | xargs grep -i <keyword> */
wdenk2729af92004-05-03 20:45:30 +00004926 }
wdenkc6097192002-11-03 00:24:07 +00004927
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04004928 if (available_money > toLocalCurrency ($2500))
4929 Buy a BDI3000;
4930 else
wdenk2729af92004-05-03 20:45:30 +00004931 Add a lot of aggravation and time;
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04004932
4933 if (a similar board exists) { /* hopefully... */
4934 cp -a board/<similar> board/<myboard>
4935 cp include/configs/<similar>.h include/configs/<myboard>.h
4936 } else {
4937 Create your own board support subdirectory;
4938 Create your own board include/configs/<myboard>.h file;
wdenk2729af92004-05-03 20:45:30 +00004939 }
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04004940 Edit new board/<myboard> files
4941 Edit new include/configs/<myboard>.h
wdenkc6097192002-11-03 00:24:07 +00004942
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04004943 while (!accepted) {
4944 while (!running) {
4945 do {
4946 Add / modify source code;
4947 } until (compiles);
4948 Debug;
4949 if (clueless)
4950 email("Hi, I am having problems...");
4951 }
4952 Send patch file to the U-Boot email list;
4953 if (reasonable critiques)
4954 Incorporate improvements from email list code review;
4955 else
4956 Defend code as written;
wdenk2729af92004-05-03 20:45:30 +00004957 }
wdenkc6097192002-11-03 00:24:07 +00004958
wdenk2729af92004-05-03 20:45:30 +00004959 return 0;
4960}
4961
4962void no_more_time (int sig)
4963{
4964 hire_a_guru();
4965}
wdenkc6097192002-11-03 00:24:07 +00004966
4967
wdenk2729af92004-05-03 20:45:30 +00004968Coding Standards:
4969-----------------
wdenkc6097192002-11-03 00:24:07 +00004970
wdenk2729af92004-05-03 20:45:30 +00004971All contributions to U-Boot should conform to the Linux kernel
Baruch Siach659208d2017-12-10 17:34:35 +02004972coding style; see the kernel coding style guide at
4973https://www.kernel.org/doc/html/latest/process/coding-style.html, and the
4974script "scripts/Lindent" in your Linux kernel source directory.
wdenk2729af92004-05-03 20:45:30 +00004975
Detlev Zundel2c051652006-09-01 15:39:02 +02004976Source files originating from a different project (for example the
4977MTD subsystem) are generally exempt from these guidelines and are not
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08004978reformatted to ease subsequent migration to newer versions of those
Detlev Zundel2c051652006-09-01 15:39:02 +02004979sources.
4980
4981Please note that U-Boot is implemented in C (and to some small parts in
4982Assembler); no C++ is used, so please do not use C++ style comments (//)
4983in your code.
wdenk2729af92004-05-03 20:45:30 +00004984
4985Please also stick to the following formatting rules:
4986- remove any trailing white space
Wolfgang Denk7ca92962011-07-27 10:59:55 +00004987- use TAB characters for indentation and vertical alignment, not spaces
wdenk2729af92004-05-03 20:45:30 +00004988- make sure NOT to use DOS '\r\n' line feeds
Wolfgang Denk7ca92962011-07-27 10:59:55 +00004989- do not add more than 2 consecutive empty lines to source files
wdenk2729af92004-05-03 20:45:30 +00004990- do not add trailing empty lines to source files
4991
4992Submissions which do not conform to the standards may be returned
4993with a request to reformat the changes.
wdenkc6097192002-11-03 00:24:07 +00004994
4995
wdenk2729af92004-05-03 20:45:30 +00004996Submitting Patches:
4997-------------------
wdenkc6097192002-11-03 00:24:07 +00004998
wdenk2729af92004-05-03 20:45:30 +00004999Since the number of patches for U-Boot is growing, we need to
5000establish some rules. Submissions which do not conform to these rules
5001may be rejected, even when they contain important and valuable stuff.
wdenkc6097192002-11-03 00:24:07 +00005002
Magnus Lilja0d28f342008-08-06 19:32:33 +02005003Please see http://www.denx.de/wiki/U-Boot/Patches for details.
Wolfgang Denk218ca722008-03-26 10:40:12 +01005004
Wolfgang Denk06682362008-12-30 22:56:11 +01005005Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>;
S. Lockwood-Childs1dade182017-11-14 22:56:42 -08005006see https://lists.denx.de/listinfo/u-boot
Wolfgang Denk06682362008-12-30 22:56:11 +01005007
wdenk2729af92004-05-03 20:45:30 +00005008When you send a patch, please include the following information with
5009it:
wdenkc6097192002-11-03 00:24:07 +00005010
wdenk2729af92004-05-03 20:45:30 +00005011* For bug fixes: a description of the bug and how your patch fixes
5012 this bug. Please try to include a way of demonstrating that the
5013 patch actually fixes something.
wdenkc6097192002-11-03 00:24:07 +00005014
wdenk2729af92004-05-03 20:45:30 +00005015* For new features: a description of the feature and your
5016 implementation.
wdenkc6097192002-11-03 00:24:07 +00005017
wdenk2729af92004-05-03 20:45:30 +00005018* A CHANGELOG entry as plaintext (separate from the patch)
5019
Robert P. J. Day7207b362015-12-19 07:16:10 -05005020* For major contributions, add a MAINTAINERS file with your
5021 information and associated file and directory references.
wdenk2729af92004-05-03 20:45:30 +00005022
Albert ARIBAUD27af9302013-09-11 15:52:51 +02005023* When you add support for a new board, don't forget to add a
5024 maintainer e-mail address to the boards.cfg file, too.
wdenk2729af92004-05-03 20:45:30 +00005025
5026* If your patch adds new configuration options, don't forget to
5027 document these in the README file.
5028
Wolfgang Denk218ca722008-03-26 10:40:12 +01005029* The patch itself. If you are using git (which is *strongly*
5030 recommended) you can easily generate the patch using the
Wolfgang Denk7ca92962011-07-27 10:59:55 +00005031 "git format-patch". If you then use "git send-email" to send it to
Wolfgang Denk218ca722008-03-26 10:40:12 +01005032 the U-Boot mailing list, you will avoid most of the common problems
5033 with some other mail clients.
wdenk2729af92004-05-03 20:45:30 +00005034
Wolfgang Denk218ca722008-03-26 10:40:12 +01005035 If you cannot use git, use "diff -purN OLD NEW". If your version of
5036 diff does not support these options, then get the latest version of
5037 GNU diff.
wdenk2729af92004-05-03 20:45:30 +00005038
Wolfgang Denk218ca722008-03-26 10:40:12 +01005039 The current directory when running this command shall be the parent
5040 directory of the U-Boot source tree (i. e. please make sure that
5041 your patch includes sufficient directory information for the
5042 affected files).
5043
5044 We prefer patches as plain text. MIME attachments are discouraged,
5045 and compressed attachments must not be used.
wdenk2729af92004-05-03 20:45:30 +00005046
5047* If one logical set of modifications affects or creates several
5048 files, all these changes shall be submitted in a SINGLE patch file.
5049
5050* Changesets that contain different, unrelated modifications shall be
5051 submitted as SEPARATE patches, one patch per changeset.
5052
5053
5054Notes:
5055
Simon Glass6de80f22016-07-27 20:33:08 -06005056* Before sending the patch, run the buildman script on your patched
wdenk2729af92004-05-03 20:45:30 +00005057 source tree and make sure that no errors or warnings are reported
5058 for any of the boards.
5059
5060* Keep your modifications to the necessary minimum: A patch
5061 containing several unrelated changes or arbitrary reformats will be
5062 returned with a request to re-formatting / split it.
5063
5064* If you modify existing code, make sure that your new code does not
5065 add to the memory footprint of the code ;-) Small is beautiful!
5066 When adding new features, these should compile conditionally only
5067 (using #ifdef), and the resulting code with the new feature
5068 disabled must not need more memory than the old code without your
5069 modification.
wdenk90dc6702005-05-03 14:12:25 +00005070
Wolfgang Denk06682362008-12-30 22:56:11 +01005071* Remember that there is a size limit of 100 kB per message on the
5072 u-boot mailing list. Bigger patches will be moderated. If they are
5073 reasonable and not too big, they will be acknowledged. But patches
5074 bigger than the size limit should be avoided.