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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_SYS_DAVINCI_EMAC_PHY_COUNT
981 Define this if you have more then 3 PHYs.
982
Macpaul Linb3dbf4a52010-12-21 16:59:46 +0800983 CONFIG_FTGMAC100
984 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet
985
986 CONFIG_FTGMAC100_EGIGA
987 Define this to use GE link update with gigabit PHY.
988 Define this if FTGMAC100 is connected to gigabit PHY.
989 If your system has 10/100 PHY only, it might not occur
990 wrong behavior. Because PHY usually return timeout or
991 useless data when polling gigabit status and gigabit
992 control registers. This behavior won't affect the
993 correctnessof 10/100 link speed update.
994
Yoshihiro Shimoda3d0075f2011-01-27 10:06:03 +0900995 CONFIG_SH_ETHER
996 Support for Renesas on-chip Ethernet controller
997
998 CONFIG_SH_ETHER_USE_PORT
999 Define the number of ports to be used
1000
1001 CONFIG_SH_ETHER_PHY_ADDR
1002 Define the ETH PHY's address
1003
Yoshihiro Shimoda68260aa2011-01-27 10:06:08 +09001004 CONFIG_SH_ETHER_CACHE_WRITEBACK
1005 If this option is set, the driver enables cache flush.
1006
Heiko Schocherb2f97cf2014-07-18 06:07:19 +02001007- PWM Support:
1008 CONFIG_PWM_IMX
Robert P. J. Day5052e812016-09-13 08:35:18 -04001009 Support for PWM module on the imx6.
Heiko Schocherb2f97cf2014-07-18 06:07:19 +02001010
Vadim Bendebury5e124722011-10-17 08:36:14 +00001011- TPM Support:
Che-liang Chiou90899cc2013-04-12 11:04:34 +00001012 CONFIG_TPM
1013 Support TPM devices.
1014
Christophe Ricard0766ad22015-10-06 22:54:41 +02001015 CONFIG_TPM_TIS_INFINEON
1016 Support for Infineon i2c bus TPM devices. Only one device
Tom Wai-Hong Tam1b393db2013-04-12 11:04:37 +00001017 per system is supported at this time.
1018
Tom Wai-Hong Tam1b393db2013-04-12 11:04:37 +00001019 CONFIG_TPM_TIS_I2C_BURST_LIMITATION
1020 Define the burst count bytes upper limit
1021
Christophe Ricard3aa74082016-01-21 23:27:13 +01001022 CONFIG_TPM_ST33ZP24
1023 Support for STMicroelectronics TPM devices. Requires DM_TPM support.
1024
1025 CONFIG_TPM_ST33ZP24_I2C
1026 Support for STMicroelectronics ST33ZP24 I2C devices.
1027 Requires TPM_ST33ZP24 and I2C.
1028
Christophe Ricardb75fdc12016-01-21 23:27:14 +01001029 CONFIG_TPM_ST33ZP24_SPI
1030 Support for STMicroelectronics ST33ZP24 SPI devices.
1031 Requires TPM_ST33ZP24 and SPI.
1032
Dirk Eibachc01939c2013-06-26 15:55:15 +02001033 CONFIG_TPM_ATMEL_TWI
1034 Support for Atmel TWI TPM device. Requires I2C support.
1035
Che-liang Chiou90899cc2013-04-12 11:04:34 +00001036 CONFIG_TPM_TIS_LPC
Vadim Bendebury5e124722011-10-17 08:36:14 +00001037 Support for generic parallel port TPM devices. Only one device
1038 per system is supported at this time.
1039
1040 CONFIG_TPM_TIS_BASE_ADDRESS
1041 Base address where the generic TPM device is mapped
1042 to. Contemporary x86 systems usually map it at
1043 0xfed40000.
1044
Reinhard Pfaube6c1522013-06-26 15:55:13 +02001045 CONFIG_TPM
1046 Define this to enable the TPM support library which provides
1047 functional interfaces to some TPM commands.
1048 Requires support for a TPM device.
1049
1050 CONFIG_TPM_AUTH_SESSIONS
1051 Define this to enable authorized functions in the TPM library.
1052 Requires CONFIG_TPM and CONFIG_SHA1.
1053
wdenkc6097192002-11-03 00:24:07 +00001054- USB Support:
1055 At the moment only the UHCI host controller is
Heiko Schocher064b55c2017-06-14 05:49:40 +02001056 supported (PIP405, MIP405); define
wdenkc6097192002-11-03 00:24:07 +00001057 CONFIG_USB_UHCI to enable it.
1058 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
wdenk30d56fa2004-10-09 22:44:59 +00001059 and define CONFIG_USB_STORAGE to enable the USB
wdenkc6097192002-11-03 00:24:07 +00001060 storage devices.
1061 Note:
1062 Supported are USB Keyboards and USB Floppy drives
1063 (TEAC FD-05PUB).
wdenk4d13cba2004-03-14 14:09:05 +00001064
Simon Glass9ab4ce22012-02-27 10:52:47 +00001065 CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the
1066 txfilltuning field in the EHCI controller on reset.
1067
Oleksandr Tymoshenko6e9e0622014-02-01 21:51:25 -07001068 CONFIG_USB_DWC2_REG_ADDR the physical CPU address of the DWC2
1069 HW module registers.
1070
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +02001071- USB Device:
1072 Define the below if you wish to use the USB console.
1073 Once firmware is rebuilt from a serial console issue the
1074 command "setenv stdin usbtty; setenv stdout usbtty" and
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001075 attach your USB cable. The Unix command "dmesg" should print
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +02001076 it has found a new device. The environment variable usbtty
1077 can be set to gserial or cdc_acm to enable your device to
Wolfgang Denk386eda02006-06-14 18:14:56 +02001078 appear to a USB host as a Linux gserial device or a
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +02001079 Common Device Class Abstract Control Model serial device.
1080 If you select usbtty = gserial you should be able to enumerate
1081 a Linux host by
1082 # modprobe usbserial vendor=0xVendorID product=0xProductID
1083 else if using cdc_acm, simply setting the environment
1084 variable usbtty to be cdc_acm should suffice. The following
1085 might be defined in YourBoardName.h
Wolfgang Denk386eda02006-06-14 18:14:56 +02001086
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +02001087 CONFIG_USB_DEVICE
1088 Define this to build a UDC device
wdenkc6097192002-11-03 00:24:07 +00001089
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +02001090 CONFIG_USB_TTY
1091 Define this to have a tty type of device available to
1092 talk to the UDC device
Wolfgang Denk386eda02006-06-14 18:14:56 +02001093
Vipin KUMARf9da0f82012-03-26 15:38:06 +05301094 CONFIG_USBD_HS
1095 Define this to enable the high speed support for usb
1096 device and usbtty. If this feature is enabled, a routine
1097 int is_usbd_high_speed(void)
1098 also needs to be defined by the driver to dynamically poll
1099 whether the enumeration has succeded at high speed or full
1100 speed.
1101
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001102 CONFIG_SYS_CONSOLE_IS_IN_ENV
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +02001103 Define this if you want stdin, stdout &/or stderr to
1104 be set to usbtty.
1105
Wolfgang Denk386eda02006-06-14 18:14:56 +02001106 If you have a USB-IF assigned VendorID then you may wish to
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +02001107 define your own vendor specific values either in BoardName.h
Wolfgang Denk386eda02006-06-14 18:14:56 +02001108 or directly in usbd_vendor_info.h. If you don't define
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +02001109 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME,
1110 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot
1111 should pretend to be a Linux device to it's target host.
1112
1113 CONFIG_USBD_MANUFACTURER
1114 Define this string as the name of your company for
1115 - CONFIG_USBD_MANUFACTURER "my company"
Wolfgang Denk386eda02006-06-14 18:14:56 +02001116
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +02001117 CONFIG_USBD_PRODUCT_NAME
1118 Define this string as the name of your product
1119 - CONFIG_USBD_PRODUCT_NAME "acme usb device"
1120
1121 CONFIG_USBD_VENDORID
1122 Define this as your assigned Vendor ID from the USB
1123 Implementors Forum. This *must* be a genuine Vendor ID
1124 to avoid polluting the USB namespace.
1125 - CONFIG_USBD_VENDORID 0xFFFF
Wolfgang Denk386eda02006-06-14 18:14:56 +02001126
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +02001127 CONFIG_USBD_PRODUCTID
1128 Define this as the unique Product ID
1129 for your device
1130 - CONFIG_USBD_PRODUCTID 0xFFFF
wdenkc6097192002-11-03 00:24:07 +00001131
Igor Grinbergd70a5602011-12-12 12:08:35 +02001132- ULPI Layer Support:
1133 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via
1134 the generic ULPI layer. The generic layer accesses the ULPI PHY
1135 via the platform viewport, so you need both the genric layer and
1136 the viewport enabled. Currently only Chipidea/ARC based
1137 viewport is supported.
1138 To enable the ULPI layer support, define CONFIG_USB_ULPI and
1139 CONFIG_USB_ULPI_VIEWPORT in your board configuration file.
Lucas Stach6d365ea2012-10-01 00:44:35 +02001140 If your ULPI phy needs a different reference clock than the
1141 standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to
1142 the appropriate value in Hz.
wdenkc6097192002-11-03 00:24:07 +00001143
1144- MMC Support:
1145 The MMC controller on the Intel PXA is supported. To
1146 enable this define CONFIG_MMC. The MMC can be
1147 accessed from the boot prompt by mapping the device
1148 to physical memory similar to flash. Command line is
Jon Loeliger602ad3b2007-06-11 19:03:39 -05001149 enabled with CONFIG_CMD_MMC. The MMC driver also works with
1150 the FAT fs. This is enabled with CONFIG_CMD_FAT.
wdenkc6097192002-11-03 00:24:07 +00001151
Yoshihiro Shimodaafb35662011-07-04 22:21:22 +00001152 CONFIG_SH_MMCIF
1153 Support for Renesas on-chip MMCIF controller
1154
1155 CONFIG_SH_MMCIF_ADDR
1156 Define the base address of MMCIF registers
1157
1158 CONFIG_SH_MMCIF_CLK
1159 Define the clock frequency for MMCIF
1160
Pierre Aubert1fd93c62014-04-24 10:30:08 +02001161 CONFIG_SUPPORT_EMMC_BOOT
1162 Enable some additional features of the eMMC boot partitions.
1163
Tom Rinib3ba6e92013-03-14 05:32:47 +00001164- USB Device Firmware Update (DFU) class support:
Marek Vasutbb4059a2018-02-16 16:41:18 +01001165 CONFIG_DFU_OVER_USB
Tom Rinib3ba6e92013-03-14 05:32:47 +00001166 This enables the USB portion of the DFU USB class
1167
Tom Rinib3ba6e92013-03-14 05:32:47 +00001168 CONFIG_DFU_MMC
1169 This enables support for exposing (e)MMC devices via DFU.
1170
Pantelis Antoniouc6631762013-03-14 05:32:52 +00001171 CONFIG_DFU_NAND
1172 This enables support for exposing NAND devices via DFU.
1173
Afzal Mohammeda9479f02013-09-18 01:15:24 +05301174 CONFIG_DFU_RAM
1175 This enables support for exposing RAM via DFU.
1176 Note: DFU spec refer to non-volatile memory usage, but
1177 allow usages beyond the scope of spec - here RAM usage,
1178 one that would help mostly the developer.
1179
Heiko Schochere7e75c72013-06-12 06:05:51 +02001180 CONFIG_SYS_DFU_DATA_BUF_SIZE
1181 Dfu transfer uses a buffer before writing data to the
1182 raw storage device. Make the size (in bytes) of this buffer
1183 configurable. The size of this buffer is also configurable
1184 through the "dfu_bufsiz" environment variable.
1185
Pantelis Antoniouea2453d2013-03-14 05:32:48 +00001186 CONFIG_SYS_DFU_MAX_FILE_SIZE
1187 When updating files rather than the raw storage device,
1188 we use a static buffer to copy the file into and then write
1189 the buffer once we've been given the whole file. Define
1190 this to the maximum filesize (in bytes) for the buffer.
1191 Default is 4 MiB if undefined.
1192
Heiko Schocher001a8312014-03-18 08:09:56 +01001193 DFU_DEFAULT_POLL_TIMEOUT
1194 Poll timeout [ms], is the timeout a device can send to the
1195 host. The host must wait for this timeout before sending
1196 a subsequent DFU_GET_STATUS request to the device.
1197
1198 DFU_MANIFEST_POLL_TIMEOUT
1199 Poll timeout [ms], which the device sends to the host when
1200 entering dfuMANIFEST state. Host waits this timeout, before
1201 sending again an USB request to the device.
1202
wdenk6705d812004-08-02 23:22:59 +00001203- Journaling Flash filesystem support:
Simon Glassb2482df2016-10-02 18:00:59 -06001204 CONFIG_JFFS2_NAND
wdenk6705d812004-08-02 23:22:59 +00001205 Define these for a default partition on a NAND device
1206
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001207 CONFIG_SYS_JFFS2_FIRST_SECTOR,
1208 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS
wdenk6705d812004-08-02 23:22:59 +00001209 Define these for a default partition on a NOR device
1210
wdenkc6097192002-11-03 00:24:07 +00001211- Keyboard Support:
Simon Glass39f615e2015-11-11 10:05:47 -07001212 See Kconfig help for available keyboard drivers.
1213
1214 CONFIG_KEYBOARD
1215
1216 Define this to enable a custom keyboard support.
1217 This simply calls drv_keyboard_init() which must be
1218 defined in your board-specific files. This option is deprecated
1219 and is only used by novena. For new boards, use driver model
1220 instead.
wdenkc6097192002-11-03 00:24:07 +00001221
1222- Video support:
Timur Tabi7d3053f2011-02-15 17:09:19 -06001223 CONFIG_FSL_DIU_FB
Wolfgang Denk04e5ae72011-09-11 21:24:09 +02001224 Enable the Freescale DIU video driver. Reference boards for
Timur Tabi7d3053f2011-02-15 17:09:19 -06001225 SOCs that have a DIU should define this macro to enable DIU
1226 support, and should also define these other macros:
1227
1228 CONFIG_SYS_DIU_ADDR
1229 CONFIG_VIDEO
Timur Tabi7d3053f2011-02-15 17:09:19 -06001230 CONFIG_CFB_CONSOLE
1231 CONFIG_VIDEO_SW_CURSOR
1232 CONFIG_VGA_AS_SINGLE_DEVICE
1233 CONFIG_VIDEO_LOGO
1234 CONFIG_VIDEO_BMP_LOGO
1235
Timur Tabiba8e76b2011-04-11 14:18:22 -05001236 The DIU driver will look for the 'video-mode' environment
1237 variable, and if defined, enable the DIU as a console during
Fabio Estevam8eca9432016-04-02 11:53:18 -03001238 boot. See the documentation file doc/README.video for a
Timur Tabiba8e76b2011-04-11 14:18:22 -05001239 description of this variable.
Timur Tabi7d3053f2011-02-15 17:09:19 -06001240
wdenkc6097192002-11-03 00:24:07 +00001241- LCD Support: CONFIG_LCD
1242
1243 Define this to enable LCD support (for output to LCD
1244 display); also select one of the supported displays
1245 by defining one of these:
1246
Stelian Pop39cf4802008-05-09 21:57:18 +02001247 CONFIG_ATMEL_LCD:
1248
1249 HITACHI TX09D70VM1CCA, 3.5", 240x320.
1250
wdenkfd3103b2003-11-25 16:55:19 +00001251 CONFIG_NEC_NL6448AC33:
wdenkc6097192002-11-03 00:24:07 +00001252
wdenkfd3103b2003-11-25 16:55:19 +00001253 NEC NL6448AC33-18. Active, color, single scan.
wdenkc6097192002-11-03 00:24:07 +00001254
wdenkfd3103b2003-11-25 16:55:19 +00001255 CONFIG_NEC_NL6448BC20
wdenkc6097192002-11-03 00:24:07 +00001256
wdenkfd3103b2003-11-25 16:55:19 +00001257 NEC NL6448BC20-08. 6.5", 640x480.
1258 Active, color, single scan.
1259
1260 CONFIG_NEC_NL6448BC33_54
1261
1262 NEC NL6448BC33-54. 10.4", 640x480.
wdenkc6097192002-11-03 00:24:07 +00001263 Active, color, single scan.
1264
1265 CONFIG_SHARP_16x9
1266
1267 Sharp 320x240. Active, color, single scan.
1268 It isn't 16x9, and I am not sure what it is.
1269
1270 CONFIG_SHARP_LQ64D341
1271
1272 Sharp LQ64D341 display, 640x480.
1273 Active, color, single scan.
1274
1275 CONFIG_HLD1045
1276
1277 HLD1045 display, 640x480.
1278 Active, color, single scan.
1279
1280 CONFIG_OPTREX_BW
1281
1282 Optrex CBL50840-2 NF-FW 99 22 M5
1283 or
1284 Hitachi LMG6912RPFC-00T
1285 or
1286 Hitachi SP14Q002
1287
1288 320x240. Black & white.
1289
Simon Glass676d3192012-10-17 13:24:54 +00001290 CONFIG_LCD_ALIGNMENT
1291
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08001292 Normally the LCD is page-aligned (typically 4KB). If this is
Simon Glass676d3192012-10-17 13:24:54 +00001293 defined then the LCD will be aligned to this value instead.
1294 For ARM it is sometimes useful to use MMU_SECTION_SIZE
1295 here, since it is cheaper to change data cache settings on
1296 a per-section basis.
1297
1298
Hannes Petermaier604c7d42015-03-27 08:01:38 +01001299 CONFIG_LCD_ROTATION
1300
1301 Sometimes, for example if the display is mounted in portrait
1302 mode or even if it's mounted landscape but rotated by 180degree,
1303 we need to rotate our content of the display relative to the
1304 framebuffer, so that user can read the messages which are
1305 printed out.
1306 Once CONFIG_LCD_ROTATION is defined, the lcd_console will be
1307 initialized with a given rotation from "vl_rot" out of
1308 "vidinfo_t" which is provided by the board specific code.
1309 The value for vl_rot is coded as following (matching to
1310 fbcon=rotate:<n> linux-kernel commandline):
1311 0 = no rotation respectively 0 degree
1312 1 = 90 degree rotation
1313 2 = 180 degree rotation
1314 3 = 270 degree rotation
1315
1316 If CONFIG_LCD_ROTATION is not defined, the console will be
1317 initialized with 0degree rotation.
1318
Tom Wai-Hong Tam45d7f522012-09-28 15:11:16 +00001319 CONFIG_LCD_BMP_RLE8
1320
1321 Support drawing of RLE8-compressed bitmaps on the LCD.
1322
Tom Wai-Hong Tam735987c2012-12-05 14:46:40 +00001323 CONFIG_I2C_EDID
1324
1325 Enables an 'i2c edid' command which can read EDID
1326 information over I2C from an attached LCD display.
1327
wdenk7152b1d2003-09-05 23:19:14 +00001328- Splash Screen Support: CONFIG_SPLASH_SCREEN
wdenkd791b1d2003-04-20 14:04:18 +00001329
wdenk8bde7f72003-06-27 21:31:46 +00001330 If this option is set, the environment is checked for
1331 a variable "splashimage". If found, the usual display
1332 of logo, copyright and system information on the LCD
wdenke94d2cd2004-06-30 22:59:18 +00001333 is suppressed and the BMP image at the address
wdenk8bde7f72003-06-27 21:31:46 +00001334 specified in "splashimage" is loaded instead. The
1335 console is redirected to the "nulldev", too. This
1336 allows for a "silent" boot where a splash screen is
1337 loaded very quickly after power-on.
wdenkd791b1d2003-04-20 14:04:18 +00001338
Nikita Kiryanovc0880482013-02-24 21:28:43 +00001339 CONFIG_SPLASHIMAGE_GUARD
1340
1341 If this option is set, then U-Boot will prevent the environment
1342 variable "splashimage" from being set to a problematic address
Fabio Estevamab5645f2016-03-23 12:46:12 -03001343 (see doc/README.displaying-bmps).
Nikita Kiryanovc0880482013-02-24 21:28:43 +00001344 This option is useful for targets where, due to alignment
1345 restrictions, an improperly aligned BMP image will cause a data
1346 abort. If you think you will not have problems with unaligned
1347 accesses (for example because your toolchain prevents them)
1348 there is no need to set this option.
1349
Matthias Weisser1ca298c2009-07-09 16:07:30 +02001350 CONFIG_SPLASH_SCREEN_ALIGN
1351
1352 If this option is set the splash image can be freely positioned
1353 on the screen. Environment variable "splashpos" specifies the
1354 position as "x,y". If a positive number is given it is used as
1355 number of pixel from left/top. If a negative number is given it
1356 is used as number of pixel from right/bottom. You can also
1357 specify 'm' for centering the image.
1358
1359 Example:
1360 setenv splashpos m,m
1361 => image at center of screen
1362
1363 setenv splashpos 30,20
1364 => image at x = 30 and y = 20
1365
1366 setenv splashpos -10,m
1367 => vertically centered image
1368 at x = dspWidth - bmpWidth - 9
1369
Stefan Roese98f4a3d2005-09-22 09:04:17 +02001370- Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
1371
1372 If this option is set, additionally to standard BMP
1373 images, gzipped BMP images can be displayed via the
1374 splashscreen support or the bmp command.
1375
Anatolij Gustschind5011762010-03-15 14:50:25 +01001376- Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8
1377
1378 If this option is set, 8-bit RLE compressed BMP images
1379 can be displayed via the splashscreen support or the
1380 bmp command.
1381
wdenkc29fdfc2003-08-29 20:57:53 +00001382- Compression support:
Kees Cook8ef70472013-08-16 07:59:12 -07001383 CONFIG_GZIP
1384
1385 Enabled by default to support gzip compressed images.
1386
wdenkc29fdfc2003-08-29 20:57:53 +00001387 CONFIG_BZIP2
1388
1389 If this option is set, support for bzip2 compressed
1390 images is included. If not, only uncompressed and gzip
1391 compressed images are supported.
1392
wdenk42d1f032003-10-15 23:53:47 +00001393 NOTE: the bzip2 algorithm requires a lot of RAM, so
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001394 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should
wdenk42d1f032003-10-15 23:53:47 +00001395 be at least 4MB.
wdenkd791b1d2003-04-20 14:04:18 +00001396
wdenk17ea1172004-06-06 21:51:03 +00001397- MII/PHY support:
wdenk17ea1172004-06-06 21:51:03 +00001398 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
1399
1400 The clock frequency of the MII bus
1401
wdenk17ea1172004-06-06 21:51:03 +00001402 CONFIG_PHY_RESET_DELAY
1403
1404 Some PHY like Intel LXT971A need extra delay after
1405 reset before any MII register access is possible.
1406 For such PHY, set this option to the usec delay
1407 required. (minimum 300usec for LXT971A)
1408
1409 CONFIG_PHY_CMD_DELAY (ppc4xx)
1410
1411 Some PHY like Intel LXT971A need extra delay after
1412 command issued before MII status register can be read
1413
wdenkc6097192002-11-03 00:24:07 +00001414- IP address:
1415 CONFIG_IPADDR
1416
1417 Define a default value for the IP address to use for
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001418 the default Ethernet interface, in case this is not
wdenkc6097192002-11-03 00:24:07 +00001419 determined through e.g. bootp.
Wolfgang Denk1ebcd652011-10-26 10:21:22 +00001420 (Environment variable "ipaddr")
wdenkc6097192002-11-03 00:24:07 +00001421
1422- Server IP address:
1423 CONFIG_SERVERIP
1424
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001425 Defines a default value for the IP address of a TFTP
wdenkc6097192002-11-03 00:24:07 +00001426 server to contact when using the "tftboot" command.
Wolfgang Denk1ebcd652011-10-26 10:21:22 +00001427 (Environment variable "serverip")
wdenkc6097192002-11-03 00:24:07 +00001428
Robin Getz97cfe862009-07-21 12:15:28 -04001429 CONFIG_KEEP_SERVERADDR
1430
1431 Keeps the server's MAC address, in the env 'serveraddr'
1432 for passing to bootargs (like Linux's netconsole option)
1433
Wolfgang Denk1ebcd652011-10-26 10:21:22 +00001434- Gateway IP address:
1435 CONFIG_GATEWAYIP
1436
1437 Defines a default value for the IP address of the
1438 default router where packets to other networks are
1439 sent to.
1440 (Environment variable "gatewayip")
1441
1442- Subnet mask:
1443 CONFIG_NETMASK
1444
1445 Defines a default value for the subnet mask (or
1446 routing prefix) which is used to determine if an IP
1447 address belongs to the local subnet or needs to be
1448 forwarded through a router.
1449 (Environment variable "netmask")
1450
David Updegraff53a5c422007-06-11 10:41:07 -05001451- Multicast TFTP Mode:
1452 CONFIG_MCAST_TFTP
1453
1454 Defines whether you want to support multicast TFTP as per
1455 rfc-2090; for example to work with atftp. Lets lots of targets
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001456 tftp down the same boot image concurrently. Note: the Ethernet
David Updegraff53a5c422007-06-11 10:41:07 -05001457 driver in use must provide a function: mcast() to join/leave a
1458 multicast group.
1459
wdenkc6097192002-11-03 00:24:07 +00001460- BOOTP Recovery Mode:
1461 CONFIG_BOOTP_RANDOM_DELAY
1462
1463 If you have many targets in a network that try to
1464 boot using BOOTP, you may want to avoid that all
1465 systems send out BOOTP requests at precisely the same
1466 moment (which would happen for instance at recovery
1467 from a power failure, when all systems will try to
1468 boot, thus flooding the BOOTP server. Defining
1469 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
1470 inserted before sending out BOOTP requests. The
Wolfgang Denk6c33c782007-08-06 23:21:05 +02001471 following delays are inserted then:
wdenkc6097192002-11-03 00:24:07 +00001472
1473 1st BOOTP request: delay 0 ... 1 sec
1474 2nd BOOTP request: delay 0 ... 2 sec
1475 3rd BOOTP request: delay 0 ... 4 sec
1476 4th and following
1477 BOOTP requests: delay 0 ... 8 sec
1478
Thierry Reding92ac8ac2014-08-19 10:21:24 +02001479 CONFIG_BOOTP_ID_CACHE_SIZE
1480
1481 BOOTP packets are uniquely identified using a 32-bit ID. The
1482 server will copy the ID from client requests to responses and
1483 U-Boot will use this to determine if it is the destination of
1484 an incoming response. Some servers will check that addresses
1485 aren't in use before handing them out (usually using an ARP
1486 ping) and therefore take up to a few hundred milliseconds to
1487 respond. Network congestion may also influence the time it
1488 takes for a response to make it back to the client. If that
1489 time is too long, U-Boot will retransmit requests. In order
1490 to allow earlier responses to still be accepted after these
1491 retransmissions, U-Boot's BOOTP client keeps a small cache of
1492 IDs. The CONFIG_BOOTP_ID_CACHE_SIZE controls the size of this
1493 cache. The default is to keep IDs for up to four outstanding
1494 requests. Increasing this will allow U-Boot to accept offers
1495 from a BOOTP client in networks with unusually high latency.
1496
stroesefe389a82003-08-28 14:17:32 +00001497- DHCP Advanced Options:
Jon Loeliger1fe80d72007-07-09 22:08:34 -05001498 You can fine tune the DHCP functionality by defining
1499 CONFIG_BOOTP_* symbols:
stroesefe389a82003-08-28 14:17:32 +00001500
Jon Loeliger1fe80d72007-07-09 22:08:34 -05001501 CONFIG_BOOTP_NISDOMAIN
Jon Loeliger1fe80d72007-07-09 22:08:34 -05001502 CONFIG_BOOTP_BOOTFILESIZE
Jon Loeliger1fe80d72007-07-09 22:08:34 -05001503 CONFIG_BOOTP_SEND_HOSTNAME
1504 CONFIG_BOOTP_NTPSERVER
1505 CONFIG_BOOTP_TIMEOFFSET
1506 CONFIG_BOOTP_VENDOREX
Joe Hershberger2c00e092012-05-23 07:59:19 +00001507 CONFIG_BOOTP_MAY_FAIL
stroesefe389a82003-08-28 14:17:32 +00001508
Wilson Callan5d110f02007-07-28 10:56:13 -04001509 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip
1510 environment variable, not the BOOTP server.
stroesefe389a82003-08-28 14:17:32 +00001511
Joe Hershberger2c00e092012-05-23 07:59:19 +00001512 CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found
1513 after the configured retry count, the call will fail
1514 instead of starting over. This can be used to fail over
1515 to Link-local IP address configuration if the DHCP server
1516 is not available.
1517
stroesefe389a82003-08-28 14:17:32 +00001518 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
1519 to do a dynamic update of a DNS server. To do this, they
1520 need the hostname of the DHCP requester.
Wilson Callan5d110f02007-07-28 10:56:13 -04001521 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content
Jon Loeliger1fe80d72007-07-09 22:08:34 -05001522 of the "hostname" environment variable is passed as
1523 option 12 to the DHCP server.
stroesefe389a82003-08-28 14:17:32 +00001524
Aras Vaichasd9a2f412008-03-26 09:43:57 +11001525 CONFIG_BOOTP_DHCP_REQUEST_DELAY
1526
1527 A 32bit value in microseconds for a delay between
1528 receiving a "DHCP Offer" and sending the "DHCP Request".
1529 This fixes a problem with certain DHCP servers that don't
1530 respond 100% of the time to a "DHCP request". E.g. On an
1531 AT91RM9200 processor running at 180MHz, this delay needed
1532 to be *at least* 15,000 usec before a Windows Server 2003
1533 DHCP server would reply 100% of the time. I recommend at
1534 least 50,000 usec to be safe. The alternative is to hope
1535 that one of the retries will be successful but note that
1536 the DHCP timeout and retry process takes a longer than
1537 this delay.
1538
Joe Hershbergerd22c3382012-05-23 08:00:12 +00001539 - Link-local IP address negotiation:
1540 Negotiate with other link-local clients on the local network
1541 for an address that doesn't require explicit configuration.
1542 This is especially useful if a DHCP server cannot be guaranteed
1543 to exist in all environments that the device must operate.
1544
1545 See doc/README.link-local for more information.
1546
Prabhakar Kushwaha24acb832017-11-23 16:51:32 +05301547 - MAC address from environment variables
1548
1549 FDT_SEQ_MACADDR_FROM_ENV
1550
1551 Fix-up device tree with MAC addresses fetched sequentially from
1552 environment variables. This config work on assumption that
1553 non-usable ethernet node of device-tree are either not present
1554 or their status has been marked as "disabled".
1555
wdenka3d991b2004-04-15 21:48:45 +00001556 - CDP Options:
wdenk6e592382004-04-18 17:39:38 +00001557 CONFIG_CDP_DEVICE_ID
wdenka3d991b2004-04-15 21:48:45 +00001558
1559 The device id used in CDP trigger frames.
1560
1561 CONFIG_CDP_DEVICE_ID_PREFIX
1562
1563 A two character string which is prefixed to the MAC address
1564 of the device.
1565
1566 CONFIG_CDP_PORT_ID
1567
1568 A printf format string which contains the ascii name of
1569 the port. Normally is set to "eth%d" which sets
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001570 eth0 for the first Ethernet, eth1 for the second etc.
wdenka3d991b2004-04-15 21:48:45 +00001571
1572 CONFIG_CDP_CAPABILITIES
1573
1574 A 32bit integer which indicates the device capabilities;
1575 0x00000010 for a normal host which does not forwards.
1576
1577 CONFIG_CDP_VERSION
1578
1579 An ascii string containing the version of the software.
1580
1581 CONFIG_CDP_PLATFORM
1582
1583 An ascii string containing the name of the platform.
1584
1585 CONFIG_CDP_TRIGGER
1586
1587 A 32bit integer sent on the trigger.
1588
1589 CONFIG_CDP_POWER_CONSUMPTION
1590
1591 A 16bit integer containing the power consumption of the
1592 device in .1 of milliwatts.
1593
1594 CONFIG_CDP_APPLIANCE_VLAN_TYPE
1595
1596 A byte containing the id of the VLAN.
1597
Uri Mashiach79267ed2017-01-19 10:51:05 +02001598- Status LED: CONFIG_LED_STATUS
wdenkc6097192002-11-03 00:24:07 +00001599
1600 Several configurations allow to display the current
1601 status using a LED. For instance, the LED will blink
1602 fast while running U-Boot code, stop blinking as
1603 soon as a reply to a BOOTP request was received, and
1604 start blinking slow once the Linux kernel is running
1605 (supported by a status LED driver in the Linux
Uri Mashiach79267ed2017-01-19 10:51:05 +02001606 kernel). Defining CONFIG_LED_STATUS enables this
wdenkc6097192002-11-03 00:24:07 +00001607 feature in U-Boot.
1608
Igor Grinberg1df7bbb2013-11-08 01:03:50 +02001609 Additional options:
1610
Uri Mashiach79267ed2017-01-19 10:51:05 +02001611 CONFIG_LED_STATUS_GPIO
Igor Grinberg1df7bbb2013-11-08 01:03:50 +02001612 The status LED can be connected to a GPIO pin.
1613 In such cases, the gpio_led driver can be used as a
Uri Mashiach79267ed2017-01-19 10:51:05 +02001614 status LED backend implementation. Define CONFIG_LED_STATUS_GPIO
Igor Grinberg1df7bbb2013-11-08 01:03:50 +02001615 to include the gpio_led driver in the U-Boot binary.
1616
Igor Grinberg9dfdcdf2013-11-08 01:03:52 +02001617 CONFIG_GPIO_LED_INVERTED_TABLE
1618 Some GPIO connected LEDs may have inverted polarity in which
1619 case the GPIO high value corresponds to LED off state and
1620 GPIO low value corresponds to LED on state.
1621 In such cases CONFIG_GPIO_LED_INVERTED_TABLE may be defined
1622 with a list of GPIO LEDs that have inverted polarity.
1623
Heiko Schocher3f4978c2012-01-16 21:12:24 +00001624- I2C Support: CONFIG_SYS_I2C
wdenkc6097192002-11-03 00:24:07 +00001625
Heiko Schocher3f4978c2012-01-16 21:12:24 +00001626 This enable the NEW i2c subsystem, and will allow you to use
1627 i2c commands at the u-boot command line (as long as you set
1628 CONFIG_CMD_I2C in CONFIG_COMMANDS) and communicate with i2c
1629 based realtime clock chips or other i2c devices. See
1630 common/cmd_i2c.c for a description of the command line
1631 interface.
1632
1633 ported i2c driver to the new framework:
Heiko Schocherea818db2013-01-29 08:53:15 +01001634 - drivers/i2c/soft_i2c.c:
1635 - activate first bus with CONFIG_SYS_I2C_SOFT define
1636 CONFIG_SYS_I2C_SOFT_SPEED and CONFIG_SYS_I2C_SOFT_SLAVE
1637 for defining speed and slave address
1638 - activate second bus with I2C_SOFT_DECLARATIONS2 define
1639 CONFIG_SYS_I2C_SOFT_SPEED_2 and CONFIG_SYS_I2C_SOFT_SLAVE_2
1640 for defining speed and slave address
1641 - activate third bus with I2C_SOFT_DECLARATIONS3 define
1642 CONFIG_SYS_I2C_SOFT_SPEED_3 and CONFIG_SYS_I2C_SOFT_SLAVE_3
1643 for defining speed and slave address
1644 - activate fourth bus with I2C_SOFT_DECLARATIONS4 define
1645 CONFIG_SYS_I2C_SOFT_SPEED_4 and CONFIG_SYS_I2C_SOFT_SLAVE_4
1646 for defining speed and slave address
Heiko Schocher3f4978c2012-01-16 21:12:24 +00001647
Heiko Schocher00f792e2012-10-24 13:48:22 +02001648 - drivers/i2c/fsl_i2c.c:
1649 - activate i2c driver with CONFIG_SYS_I2C_FSL
1650 define CONFIG_SYS_FSL_I2C_OFFSET for setting the register
1651 offset CONFIG_SYS_FSL_I2C_SPEED for the i2c speed and
1652 CONFIG_SYS_FSL_I2C_SLAVE for the slave addr of the first
1653 bus.
Wolfgang Denk93e14592013-10-04 17:43:24 +02001654 - If your board supports a second fsl i2c bus, define
Heiko Schocher00f792e2012-10-24 13:48:22 +02001655 CONFIG_SYS_FSL_I2C2_OFFSET for the register offset
1656 CONFIG_SYS_FSL_I2C2_SPEED for the speed and
1657 CONFIG_SYS_FSL_I2C2_SLAVE for the slave address of the
1658 second bus.
1659
Simon Glass1f2ba722012-10-30 07:28:53 +00001660 - drivers/i2c/tegra_i2c.c:
Nobuhiro Iwamatsu10cee512013-10-11 16:23:53 +09001661 - activate this driver with CONFIG_SYS_I2C_TEGRA
1662 - This driver adds 4 i2c buses with a fix speed from
1663 100000 and the slave addr 0!
Simon Glass1f2ba722012-10-30 07:28:53 +00001664
Dirk Eibach880540d2013-04-25 02:40:01 +00001665 - drivers/i2c/ppc4xx_i2c.c
1666 - activate this driver with CONFIG_SYS_I2C_PPC4XX
1667 - CONFIG_SYS_I2C_PPC4XX_CH0 activate hardware channel 0
1668 - CONFIG_SYS_I2C_PPC4XX_CH1 activate hardware channel 1
1669
tremfac96402013-09-21 18:13:35 +02001670 - drivers/i2c/i2c_mxc.c
1671 - activate this driver with CONFIG_SYS_I2C_MXC
Albert ARIBAUD \\(3ADEV\\)03544c62015-09-21 22:43:38 +02001672 - enable bus 1 with CONFIG_SYS_I2C_MXC_I2C1
1673 - enable bus 2 with CONFIG_SYS_I2C_MXC_I2C2
1674 - enable bus 3 with CONFIG_SYS_I2C_MXC_I2C3
1675 - enable bus 4 with CONFIG_SYS_I2C_MXC_I2C4
tremfac96402013-09-21 18:13:35 +02001676 - define speed for bus 1 with CONFIG_SYS_MXC_I2C1_SPEED
1677 - define slave for bus 1 with CONFIG_SYS_MXC_I2C1_SLAVE
1678 - define speed for bus 2 with CONFIG_SYS_MXC_I2C2_SPEED
1679 - define slave for bus 2 with CONFIG_SYS_MXC_I2C2_SLAVE
1680 - define speed for bus 3 with CONFIG_SYS_MXC_I2C3_SPEED
1681 - define slave for bus 3 with CONFIG_SYS_MXC_I2C3_SLAVE
Albert ARIBAUD \\(3ADEV\\)03544c62015-09-21 22:43:38 +02001682 - define speed for bus 4 with CONFIG_SYS_MXC_I2C4_SPEED
1683 - define slave for bus 4 with CONFIG_SYS_MXC_I2C4_SLAVE
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08001684 If those defines are not set, default value is 100000
tremfac96402013-09-21 18:13:35 +02001685 for speed, and 0 for slave.
1686
Nobuhiro Iwamatsu1086bfa2013-09-27 16:58:30 +09001687 - drivers/i2c/rcar_i2c.c:
1688 - activate this driver with CONFIG_SYS_I2C_RCAR
1689 - This driver adds 4 i2c buses
1690
1691 - CONFIG_SYS_RCAR_I2C0_BASE for setting the register channel 0
1692 - CONFIG_SYS_RCAR_I2C0_SPEED for for the speed channel 0
1693 - CONFIG_SYS_RCAR_I2C1_BASE for setting the register channel 1
1694 - CONFIG_SYS_RCAR_I2C1_SPEED for for the speed channel 1
1695 - CONFIG_SYS_RCAR_I2C2_BASE for setting the register channel 2
1696 - CONFIG_SYS_RCAR_I2C2_SPEED for for the speed channel 2
1697 - CONFIG_SYS_RCAR_I2C3_BASE for setting the register channel 3
1698 - CONFIG_SYS_RCAR_I2C3_SPEED for for the speed channel 3
1699 - CONFIF_SYS_RCAR_I2C_NUM_CONTROLLERS for number of i2c buses
1700
Nobuhiro Iwamatsu2035d772013-10-29 13:33:51 +09001701 - drivers/i2c/sh_i2c.c:
1702 - activate this driver with CONFIG_SYS_I2C_SH
1703 - This driver adds from 2 to 5 i2c buses
1704
1705 - CONFIG_SYS_I2C_SH_BASE0 for setting the register channel 0
1706 - CONFIG_SYS_I2C_SH_SPEED0 for for the speed channel 0
1707 - CONFIG_SYS_I2C_SH_BASE1 for setting the register channel 1
1708 - CONFIG_SYS_I2C_SH_SPEED1 for for the speed channel 1
1709 - CONFIG_SYS_I2C_SH_BASE2 for setting the register channel 2
1710 - CONFIG_SYS_I2C_SH_SPEED2 for for the speed channel 2
1711 - CONFIG_SYS_I2C_SH_BASE3 for setting the register channel 3
1712 - CONFIG_SYS_I2C_SH_SPEED3 for for the speed channel 3
1713 - CONFIG_SYS_I2C_SH_BASE4 for setting the register channel 4
1714 - CONFIG_SYS_I2C_SH_SPEED4 for for the speed channel 4
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08001715 - CONFIG_SYS_I2C_SH_NUM_CONTROLLERS for number of i2c buses
Nobuhiro Iwamatsu2035d772013-10-29 13:33:51 +09001716
Heiko Schocher6789e842013-10-22 11:03:18 +02001717 - drivers/i2c/omap24xx_i2c.c
1718 - activate this driver with CONFIG_SYS_I2C_OMAP24XX
1719 - CONFIG_SYS_OMAP24_I2C_SPEED speed channel 0
1720 - CONFIG_SYS_OMAP24_I2C_SLAVE slave addr channel 0
1721 - CONFIG_SYS_OMAP24_I2C_SPEED1 speed channel 1
1722 - CONFIG_SYS_OMAP24_I2C_SLAVE1 slave addr channel 1
1723 - CONFIG_SYS_OMAP24_I2C_SPEED2 speed channel 2
1724 - CONFIG_SYS_OMAP24_I2C_SLAVE2 slave addr channel 2
1725 - CONFIG_SYS_OMAP24_I2C_SPEED3 speed channel 3
1726 - CONFIG_SYS_OMAP24_I2C_SLAVE3 slave addr channel 3
1727 - CONFIG_SYS_OMAP24_I2C_SPEED4 speed channel 4
1728 - CONFIG_SYS_OMAP24_I2C_SLAVE4 slave addr channel 4
1729
Heiko Schocher0bdffe72013-11-08 07:30:53 +01001730 - drivers/i2c/zynq_i2c.c
1731 - activate this driver with CONFIG_SYS_I2C_ZYNQ
1732 - set CONFIG_SYS_I2C_ZYNQ_SPEED for speed setting
1733 - set CONFIG_SYS_I2C_ZYNQ_SLAVE for slave addr
1734
Naveen Krishna Che717fc62013-12-06 12:12:38 +05301735 - drivers/i2c/s3c24x0_i2c.c:
1736 - activate this driver with CONFIG_SYS_I2C_S3C24X0
1737 - This driver adds i2c buses (11 for Exynos5250, Exynos5420
1738 9 i2c buses for Exynos4 and 1 for S3C24X0 SoCs from Samsung)
1739 with a fix speed from 100000 and the slave addr 0!
1740
Dirk Eibachb46226b2014-07-03 09:28:18 +02001741 - drivers/i2c/ihs_i2c.c
1742 - activate this driver with CONFIG_SYS_I2C_IHS
1743 - CONFIG_SYS_I2C_IHS_CH0 activate hardware channel 0
1744 - CONFIG_SYS_I2C_IHS_SPEED_0 speed channel 0
1745 - CONFIG_SYS_I2C_IHS_SLAVE_0 slave addr channel 0
1746 - CONFIG_SYS_I2C_IHS_CH1 activate hardware channel 1
1747 - CONFIG_SYS_I2C_IHS_SPEED_1 speed channel 1
1748 - CONFIG_SYS_I2C_IHS_SLAVE_1 slave addr channel 1
1749 - CONFIG_SYS_I2C_IHS_CH2 activate hardware channel 2
1750 - CONFIG_SYS_I2C_IHS_SPEED_2 speed channel 2
1751 - CONFIG_SYS_I2C_IHS_SLAVE_2 slave addr channel 2
1752 - CONFIG_SYS_I2C_IHS_CH3 activate hardware channel 3
1753 - CONFIG_SYS_I2C_IHS_SPEED_3 speed channel 3
1754 - CONFIG_SYS_I2C_IHS_SLAVE_3 slave addr channel 3
Dirk Eibach071be892015-10-28 11:46:22 +01001755 - activate dual channel with CONFIG_SYS_I2C_IHS_DUAL
1756 - CONFIG_SYS_I2C_IHS_SPEED_0_1 speed channel 0_1
1757 - CONFIG_SYS_I2C_IHS_SLAVE_0_1 slave addr channel 0_1
1758 - CONFIG_SYS_I2C_IHS_SPEED_1_1 speed channel 1_1
1759 - CONFIG_SYS_I2C_IHS_SLAVE_1_1 slave addr channel 1_1
1760 - CONFIG_SYS_I2C_IHS_SPEED_2_1 speed channel 2_1
1761 - CONFIG_SYS_I2C_IHS_SLAVE_2_1 slave addr channel 2_1
1762 - CONFIG_SYS_I2C_IHS_SPEED_3_1 speed channel 3_1
1763 - CONFIG_SYS_I2C_IHS_SLAVE_3_1 slave addr channel 3_1
Dirk Eibachb46226b2014-07-03 09:28:18 +02001764
Heiko Schocher3f4978c2012-01-16 21:12:24 +00001765 additional defines:
1766
1767 CONFIG_SYS_NUM_I2C_BUSES
Simon Glass945a18e2016-10-02 18:01:05 -06001768 Hold the number of i2c buses you want to use.
Heiko Schocher3f4978c2012-01-16 21:12:24 +00001769
1770 CONFIG_SYS_I2C_DIRECT_BUS
1771 define this, if you don't use i2c muxes on your hardware.
1772 if CONFIG_SYS_I2C_MAX_HOPS is not defined or == 0 you can
1773 omit this define.
1774
1775 CONFIG_SYS_I2C_MAX_HOPS
1776 define how many muxes are maximal consecutively connected
1777 on one i2c bus. If you not use i2c muxes, omit this
1778 define.
1779
1780 CONFIG_SYS_I2C_BUSES
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08001781 hold a list of buses you want to use, only used if
Heiko Schocher3f4978c2012-01-16 21:12:24 +00001782 CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example
1783 a board with CONFIG_SYS_I2C_MAX_HOPS = 1 and
1784 CONFIG_SYS_NUM_I2C_BUSES = 9:
1785
1786 CONFIG_SYS_I2C_BUSES {{0, {I2C_NULL_HOP}}, \
1787 {0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \
1788 {0, {{I2C_MUX_PCA9547, 0x70, 2}}}, \
1789 {0, {{I2C_MUX_PCA9547, 0x70, 3}}}, \
1790 {0, {{I2C_MUX_PCA9547, 0x70, 4}}}, \
1791 {0, {{I2C_MUX_PCA9547, 0x70, 5}}}, \
1792 {1, {I2C_NULL_HOP}}, \
1793 {1, {{I2C_MUX_PCA9544, 0x72, 1}}}, \
1794 {1, {{I2C_MUX_PCA9544, 0x72, 2}}}, \
1795 }
1796
1797 which defines
1798 bus 0 on adapter 0 without a mux
Heiko Schocherea818db2013-01-29 08:53:15 +01001799 bus 1 on adapter 0 with a PCA9547 on address 0x70 port 1
1800 bus 2 on adapter 0 with a PCA9547 on address 0x70 port 2
1801 bus 3 on adapter 0 with a PCA9547 on address 0x70 port 3
1802 bus 4 on adapter 0 with a PCA9547 on address 0x70 port 4
1803 bus 5 on adapter 0 with a PCA9547 on address 0x70 port 5
Heiko Schocher3f4978c2012-01-16 21:12:24 +00001804 bus 6 on adapter 1 without a mux
Heiko Schocherea818db2013-01-29 08:53:15 +01001805 bus 7 on adapter 1 with a PCA9544 on address 0x72 port 1
1806 bus 8 on adapter 1 with a PCA9544 on address 0x72 port 2
Heiko Schocher3f4978c2012-01-16 21:12:24 +00001807
1808 If you do not have i2c muxes on your board, omit this define.
1809
Simon Glassce3b5d62017-05-12 21:10:00 -06001810- Legacy I2C Support:
Heiko Schocherea818db2013-01-29 08:53:15 +01001811 If you use the software i2c interface (CONFIG_SYS_I2C_SOFT)
wdenkb37c7e52003-06-30 16:24:52 +00001812 then the following macros need to be defined (examples are
1813 from include/configs/lwmon.h):
wdenkc6097192002-11-03 00:24:07 +00001814
1815 I2C_INIT
1816
wdenkb37c7e52003-06-30 16:24:52 +00001817 (Optional). Any commands necessary to enable the I2C
wdenk43d96162003-03-06 00:02:04 +00001818 controller or configure ports.
wdenkc6097192002-11-03 00:24:07 +00001819
wdenkba56f622004-02-06 23:19:44 +00001820 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
wdenkb37c7e52003-06-30 16:24:52 +00001821
wdenkc6097192002-11-03 00:24:07 +00001822 I2C_ACTIVE
1823
1824 The code necessary to make the I2C data line active
1825 (driven). If the data line is open collector, this
1826 define can be null.
1827
wdenkb37c7e52003-06-30 16:24:52 +00001828 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
1829
wdenkc6097192002-11-03 00:24:07 +00001830 I2C_TRISTATE
1831
1832 The code necessary to make the I2C data line tri-stated
1833 (inactive). If the data line is open collector, this
1834 define can be null.
1835
wdenkb37c7e52003-06-30 16:24:52 +00001836 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
1837
wdenkc6097192002-11-03 00:24:07 +00001838 I2C_READ
1839
York Sun472d5462013-04-01 11:29:11 -07001840 Code that returns true if the I2C data line is high,
1841 false if it is low.
wdenkc6097192002-11-03 00:24:07 +00001842
wdenkb37c7e52003-06-30 16:24:52 +00001843 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
1844
wdenkc6097192002-11-03 00:24:07 +00001845 I2C_SDA(bit)
1846
York Sun472d5462013-04-01 11:29:11 -07001847 If <bit> is true, sets the I2C data line high. If it
1848 is false, it clears it (low).
wdenkc6097192002-11-03 00:24:07 +00001849
wdenkb37c7e52003-06-30 16:24:52 +00001850 eg: #define I2C_SDA(bit) \
wdenk2535d602003-07-17 23:16:40 +00001851 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
wdenkba56f622004-02-06 23:19:44 +00001852 else immr->im_cpm.cp_pbdat &= ~PB_SDA
wdenkb37c7e52003-06-30 16:24:52 +00001853
wdenkc6097192002-11-03 00:24:07 +00001854 I2C_SCL(bit)
1855
York Sun472d5462013-04-01 11:29:11 -07001856 If <bit> is true, sets the I2C clock line high. If it
1857 is false, it clears it (low).
wdenkc6097192002-11-03 00:24:07 +00001858
wdenkb37c7e52003-06-30 16:24:52 +00001859 eg: #define I2C_SCL(bit) \
wdenk2535d602003-07-17 23:16:40 +00001860 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
wdenkba56f622004-02-06 23:19:44 +00001861 else immr->im_cpm.cp_pbdat &= ~PB_SCL
wdenkb37c7e52003-06-30 16:24:52 +00001862
wdenkc6097192002-11-03 00:24:07 +00001863 I2C_DELAY
1864
1865 This delay is invoked four times per clock cycle so this
1866 controls the rate of data transfer. The data rate thus
wdenkb37c7e52003-06-30 16:24:52 +00001867 is 1 / (I2C_DELAY * 4). Often defined to be something
wdenk945af8d2003-07-16 21:53:01 +00001868 like:
1869
wdenkb37c7e52003-06-30 16:24:52 +00001870 #define I2C_DELAY udelay(2)
wdenkc6097192002-11-03 00:24:07 +00001871
Mike Frysinger793b5722010-07-21 13:38:02 -04001872 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA
1873
1874 If your arch supports the generic GPIO framework (asm/gpio.h),
1875 then you may alternatively define the two GPIOs that are to be
1876 used as SCL / SDA. Any of the previous I2C_xxx macros will
1877 have GPIO-based defaults assigned to them as appropriate.
1878
1879 You should define these to the GPIO value as given directly to
1880 the generic GPIO functions.
1881
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001882 CONFIG_SYS_I2C_INIT_BOARD
wdenk47cd00f2003-03-06 13:39:27 +00001883
wdenk8bde7f72003-06-27 21:31:46 +00001884 When a board is reset during an i2c bus transfer
1885 chips might think that the current transfer is still
1886 in progress. On some boards it is possible to access
1887 the i2c SCLK line directly, either by using the
1888 processor pin as a GPIO or by having a second pin
1889 connected to the bus. If this option is defined a
1890 custom i2c_init_board() routine in boards/xxx/board.c
1891 is run early in the boot sequence.
wdenk47cd00f2003-03-06 13:39:27 +00001892
Ben Warrenbb99ad62006-09-07 16:50:54 -04001893 CONFIG_I2C_MULTI_BUS
1894
1895 This option allows the use of multiple I2C buses, each of which
Wolfgang Denkc0f40852011-10-26 10:21:21 +00001896 must have a controller. At any point in time, only one bus is
1897 active. To switch to a different bus, use the 'i2c dev' command.
Ben Warrenbb99ad62006-09-07 16:50:54 -04001898 Note that bus numbering is zero-based.
1899
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001900 CONFIG_SYS_I2C_NOPROBES
Ben Warrenbb99ad62006-09-07 16:50:54 -04001901
1902 This option specifies a list of I2C devices that will be skipped
Wolfgang Denkc0f40852011-10-26 10:21:21 +00001903 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS
Peter Tyser0f89c542009-04-18 22:34:03 -05001904 is set, specify a list of bus-device pairs. Otherwise, specify
1905 a 1D array of device addresses
Ben Warrenbb99ad62006-09-07 16:50:54 -04001906
1907 e.g.
1908 #undef CONFIG_I2C_MULTI_BUS
Wolfgang Denkc0f40852011-10-26 10:21:21 +00001909 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68}
Ben Warrenbb99ad62006-09-07 16:50:54 -04001910
1911 will skip addresses 0x50 and 0x68 on a board with one I2C bus
1912
Wolfgang Denkc0f40852011-10-26 10:21:21 +00001913 #define CONFIG_I2C_MULTI_BUS
Simon Glass945a18e2016-10-02 18:01:05 -06001914 #define CONFIG_SYS_I2C_NOPROBES {{0,0x50},{0,0x68},{1,0x54}}
Ben Warrenbb99ad62006-09-07 16:50:54 -04001915
1916 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1
1917
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001918 CONFIG_SYS_SPD_BUS_NUM
Timur Tabibe5e6182006-11-03 19:15:00 -06001919
1920 If defined, then this indicates the I2C bus number for DDR SPD.
1921 If not defined, then U-Boot assumes that SPD is on I2C bus 0.
1922
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001923 CONFIG_SYS_RTC_BUS_NUM
Stefan Roese0dc018e2007-02-20 10:51:26 +01001924
1925 If defined, then this indicates the I2C bus number for the RTC.
1926 If not defined, then U-Boot assumes that RTC is on I2C bus 0.
1927
Andrew Dyer2ac69852008-12-29 17:36:01 -06001928 CONFIG_SOFT_I2C_READ_REPEATED_START
1929
1930 defining this will force the i2c_read() function in
1931 the soft_i2c driver to perform an I2C repeated start
1932 between writing the address pointer and reading the
1933 data. If this define is omitted the default behaviour
1934 of doing a stop-start sequence will be used. Most I2C
1935 devices can use either method, but some require one or
1936 the other.
Timur Tabibe5e6182006-11-03 19:15:00 -06001937
wdenkc6097192002-11-03 00:24:07 +00001938- SPI Support: CONFIG_SPI
1939
1940 Enables SPI driver (so far only tested with
1941 SPI EEPROM, also an instance works with Crystal A/D and
1942 D/As on the SACSng board)
1943
wdenkc6097192002-11-03 00:24:07 +00001944 CONFIG_SOFT_SPI
1945
wdenk43d96162003-03-06 00:02:04 +00001946 Enables a software (bit-bang) SPI driver rather than
1947 using hardware support. This is a general purpose
1948 driver that only requires three general I/O port pins
1949 (two outputs, one input) to function. If this is
1950 defined, the board configuration must define several
1951 SPI configuration items (port pins to use, etc). For
1952 an example, see include/configs/sacsng.h.
wdenkc6097192002-11-03 00:24:07 +00001953
Ben Warren04a9e112008-01-16 22:37:35 -05001954 CONFIG_HARD_SPI
1955
1956 Enables a hardware SPI driver for general-purpose reads
1957 and writes. As with CONFIG_SOFT_SPI, the board configuration
1958 must define a list of chip-select function pointers.
Wolfgang Denkc0f40852011-10-26 10:21:21 +00001959 Currently supported on some MPC8xxx processors. For an
Ben Warren04a9e112008-01-16 22:37:35 -05001960 example, see include/configs/mpc8349emds.h.
1961
Heiko Schocherf659b572014-07-14 10:22:11 +02001962 CONFIG_SYS_SPI_MXC_WAIT
1963 Timeout for waiting until spi transfer completed.
1964 default: (CONFIG_SYS_HZ/100) /* 10 ms */
1965
Matthias Fuchs01335022007-12-27 17:12:34 +01001966- FPGA Support: CONFIG_FPGA
1967
1968 Enables FPGA subsystem.
1969
1970 CONFIG_FPGA_<vendor>
1971
1972 Enables support for specific chip vendors.
1973 (ALTERA, XILINX)
1974
1975 CONFIG_FPGA_<family>
1976
1977 Enables support for FPGA family.
1978 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
1979
1980 CONFIG_FPGA_COUNT
wdenkc6097192002-11-03 00:24:07 +00001981
wdenk43d96162003-03-06 00:02:04 +00001982 Specify the number of FPGA devices to support.
wdenkc6097192002-11-03 00:24:07 +00001983
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001984 CONFIG_SYS_FPGA_PROG_FEEDBACK
wdenkc6097192002-11-03 00:24:07 +00001985
wdenk8bde7f72003-06-27 21:31:46 +00001986 Enable printing of hash marks during FPGA configuration.
wdenkc6097192002-11-03 00:24:07 +00001987
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001988 CONFIG_SYS_FPGA_CHECK_BUSY
wdenkc6097192002-11-03 00:24:07 +00001989
wdenk43d96162003-03-06 00:02:04 +00001990 Enable checks on FPGA configuration interface busy
1991 status by the configuration function. This option
1992 will require a board or device specific function to
1993 be written.
wdenkc6097192002-11-03 00:24:07 +00001994
1995 CONFIG_FPGA_DELAY
1996
1997 If defined, a function that provides delays in the FPGA
1998 configuration driver.
1999
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002000 CONFIG_SYS_FPGA_CHECK_CTRLC
wdenkc6097192002-11-03 00:24:07 +00002001 Allow Control-C to interrupt FPGA configuration
2002
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002003 CONFIG_SYS_FPGA_CHECK_ERROR
wdenkc6097192002-11-03 00:24:07 +00002004
wdenk43d96162003-03-06 00:02:04 +00002005 Check for configuration errors during FPGA bitfile
2006 loading. For example, abort during Virtex II
2007 configuration if the INIT_B line goes low (which
2008 indicated a CRC error).
wdenkc6097192002-11-03 00:24:07 +00002009
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002010 CONFIG_SYS_FPGA_WAIT_INIT
wdenkc6097192002-11-03 00:24:07 +00002011
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08002012 Maximum time to wait for the INIT_B line to de-assert
2013 after PROB_B has been de-asserted during a Virtex II
wdenk43d96162003-03-06 00:02:04 +00002014 FPGA configuration sequence. The default time is 500
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002015 ms.
wdenkc6097192002-11-03 00:24:07 +00002016
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002017 CONFIG_SYS_FPGA_WAIT_BUSY
wdenkc6097192002-11-03 00:24:07 +00002018
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08002019 Maximum time to wait for BUSY to de-assert during
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002020 Virtex II FPGA configuration. The default is 5 ms.
wdenkc6097192002-11-03 00:24:07 +00002021
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002022 CONFIG_SYS_FPGA_WAIT_CONFIG
wdenkc6097192002-11-03 00:24:07 +00002023
wdenk43d96162003-03-06 00:02:04 +00002024 Time to wait after FPGA configuration. The default is
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002025 200 ms.
wdenkc6097192002-11-03 00:24:07 +00002026
2027- Configuration Management:
Stefan Roeseb2b8a692014-10-22 12:13:24 +02002028 CONFIG_BUILD_TARGET
2029
2030 Some SoCs need special image types (e.g. U-Boot binary
2031 with a special header) as build targets. By defining
2032 CONFIG_BUILD_TARGET in the SoC / board header, this
2033 special image will be automatically built upon calling
Simon Glass6de80f22016-07-27 20:33:08 -06002034 make / buildman.
Stefan Roeseb2b8a692014-10-22 12:13:24 +02002035
wdenkc6097192002-11-03 00:24:07 +00002036 CONFIG_IDENT_STRING
2037
wdenk43d96162003-03-06 00:02:04 +00002038 If defined, this string will be added to the U-Boot
2039 version information (U_BOOT_VERSION)
wdenkc6097192002-11-03 00:24:07 +00002040
2041- Vendor Parameter Protection:
2042
wdenk43d96162003-03-06 00:02:04 +00002043 U-Boot considers the values of the environment
2044 variables "serial#" (Board Serial Number) and
wdenk7152b1d2003-09-05 23:19:14 +00002045 "ethaddr" (Ethernet Address) to be parameters that
wdenk43d96162003-03-06 00:02:04 +00002046 are set once by the board vendor / manufacturer, and
2047 protects these variables from casual modification by
2048 the user. Once set, these variables are read-only,
2049 and write or delete attempts are rejected. You can
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002050 change this behaviour:
wdenkc6097192002-11-03 00:24:07 +00002051
2052 If CONFIG_ENV_OVERWRITE is #defined in your config
2053 file, the write protection for vendor parameters is
wdenk47cd00f2003-03-06 13:39:27 +00002054 completely disabled. Anybody can change or delete
wdenkc6097192002-11-03 00:24:07 +00002055 these parameters.
2056
Joe Hershberger92ac5202015-05-04 14:55:14 -05002057 Alternatively, if you define _both_ an ethaddr in the
2058 default env _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002059 Ethernet address is installed in the environment,
wdenkc6097192002-11-03 00:24:07 +00002060 which can be changed exactly ONCE by the user. [The
2061 serial# is unaffected by this, i. e. it remains
2062 read-only.]
2063
Joe Hershberger25980902012-12-11 22:16:31 -06002064 The same can be accomplished in a more flexible way
2065 for any variable by configuring the type of access
2066 to allow for those variables in the ".flags" variable
2067 or define CONFIG_ENV_FLAGS_LIST_STATIC.
2068
wdenkc6097192002-11-03 00:24:07 +00002069- Protected RAM:
2070 CONFIG_PRAM
2071
2072 Define this variable to enable the reservation of
2073 "protected RAM", i. e. RAM which is not overwritten
2074 by U-Boot. Define CONFIG_PRAM to hold the number of
2075 kB you want to reserve for pRAM. You can overwrite
2076 this default value by defining an environment
2077 variable "pram" to the number of kB you want to
2078 reserve. Note that the board info structure will
2079 still show the full amount of RAM. If pRAM is
2080 reserved, a new environment variable "mem" will
2081 automatically be defined to hold the amount of
2082 remaining RAM in a form that can be passed as boot
2083 argument to Linux, for instance like that:
2084
Wolfgang Denkfe126d82005-11-20 21:40:11 +01002085 setenv bootargs ... mem=\${mem}
wdenkc6097192002-11-03 00:24:07 +00002086 saveenv
2087
2088 This way you can tell Linux not to use this memory,
2089 either, which results in a memory region that will
2090 not be affected by reboots.
2091
2092 *WARNING* If your board configuration uses automatic
2093 detection of the RAM size, you must make sure that
2094 this memory test is non-destructive. So far, the
2095 following board configurations are known to be
2096 "pRAM-clean":
2097
Heiko Schocher5b8e76c2017-06-07 17:33:09 +02002098 IVMS8, IVML24, SPD8xx,
Wolfgang Denk1b0757e2012-10-24 02:36:15 +00002099 HERMES, IP860, RPXlite, LWMON,
Heiko Schocher2eb48ff2017-06-07 17:33:10 +02002100 FLAGADM
wdenkc6097192002-11-03 00:24:07 +00002101
Gabe Black40fef042012-12-02 04:55:18 +00002102- Access to physical memory region (> 4GB)
2103 Some basic support is provided for operations on memory not
2104 normally accessible to U-Boot - e.g. some architectures
2105 support access to more than 4GB of memory on 32-bit
2106 machines using physical address extension or similar.
2107 Define CONFIG_PHYSMEM to access this basic support, which
2108 currently only supports clearing the memory.
2109
wdenkc6097192002-11-03 00:24:07 +00002110- Error Recovery:
wdenkc6097192002-11-03 00:24:07 +00002111 CONFIG_NET_RETRY_COUNT
2112
wdenk43d96162003-03-06 00:02:04 +00002113 This variable defines the number of retries for
2114 network operations like ARP, RARP, TFTP, or BOOTP
2115 before giving up the operation. If not defined, a
2116 default value of 5 is used.
wdenkc6097192002-11-03 00:24:07 +00002117
Guennadi Liakhovetski40cb90e2008-04-03 17:04:19 +02002118 CONFIG_ARP_TIMEOUT
2119
2120 Timeout waiting for an ARP reply in milliseconds.
2121
Tetsuyuki Kobayashi48a3e992012-07-03 22:25:21 +00002122 CONFIG_NFS_TIMEOUT
2123
2124 Timeout in milliseconds used in NFS protocol.
2125 If you encounter "ERROR: Cannot umount" in nfs command,
2126 try longer timeout such as
2127 #define CONFIG_NFS_TIMEOUT 10000UL
2128
wdenkc6097192002-11-03 00:24:07 +00002129- Command Interpreter:
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002130 CONFIG_SYS_PROMPT_HUSH_PS2
wdenkc6097192002-11-03 00:24:07 +00002131
2132 This defines the secondary prompt string, which is
2133 printed when the command interpreter needs more input
2134 to complete a command. Usually "> ".
2135
2136 Note:
2137
wdenk8bde7f72003-06-27 21:31:46 +00002138 In the current implementation, the local variables
2139 space and global environment variables space are
2140 separated. Local variables are those you define by
2141 simply typing `name=value'. To access a local
2142 variable later on, you have write `$name' or
2143 `${name}'; to execute the contents of a variable
2144 directly type `$name' at the command prompt.
wdenkc6097192002-11-03 00:24:07 +00002145
wdenk43d96162003-03-06 00:02:04 +00002146 Global environment variables are those you use
2147 setenv/printenv to work with. To run a command stored
2148 in such a variable, you need to use the run command,
2149 and you must not use the '$' sign to access them.
wdenkc6097192002-11-03 00:24:07 +00002150
2151 To store commands and special characters in a
2152 variable, please use double quotation marks
2153 surrounding the whole text of the variable, instead
2154 of the backslashes before semicolons and special
2155 symbols.
2156
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08002157- Command Line Editing and History:
Marek Vasutf3b267b2016-01-27 04:47:55 +01002158 CONFIG_CMDLINE_PS_SUPPORT
2159
2160 Enable support for changing the command prompt string
2161 at run-time. Only static string is supported so far.
2162 The string is obtained from environment variables PS1
2163 and PS2.
2164
wdenka8c7c702003-12-06 19:49:23 +00002165- Default Environment:
wdenkc6097192002-11-03 00:24:07 +00002166 CONFIG_EXTRA_ENV_SETTINGS
2167
wdenk43d96162003-03-06 00:02:04 +00002168 Define this to contain any number of null terminated
2169 strings (variable = value pairs) that will be part of
wdenk7152b1d2003-09-05 23:19:14 +00002170 the default environment compiled into the boot image.
wdenk2262cfe2002-11-18 00:14:45 +00002171
wdenk43d96162003-03-06 00:02:04 +00002172 For example, place something like this in your
2173 board's config file:
wdenkc6097192002-11-03 00:24:07 +00002174
2175 #define CONFIG_EXTRA_ENV_SETTINGS \
2176 "myvar1=value1\0" \
2177 "myvar2=value2\0"
2178
wdenk43d96162003-03-06 00:02:04 +00002179 Warning: This method is based on knowledge about the
2180 internal format how the environment is stored by the
2181 U-Boot code. This is NOT an official, exported
2182 interface! Although it is unlikely that this format
wdenk7152b1d2003-09-05 23:19:14 +00002183 will change soon, there is no guarantee either.
wdenkc6097192002-11-03 00:24:07 +00002184 You better know what you are doing here.
2185
wdenk43d96162003-03-06 00:02:04 +00002186 Note: overly (ab)use of the default environment is
2187 discouraged. Make sure to check other ways to preset
Wolfgang Denk74de7ae2009-04-01 23:34:12 +02002188 the environment like the "source" command or the
wdenk43d96162003-03-06 00:02:04 +00002189 boot command first.
wdenkc6097192002-11-03 00:24:07 +00002190
Simon Glass06fd8532012-11-30 13:01:17 +00002191 CONFIG_DELAY_ENVIRONMENT
2192
2193 Normally the environment is loaded when the board is
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08002194 initialised so that it is available to U-Boot. This inhibits
Simon Glass06fd8532012-11-30 13:01:17 +00002195 that so that the environment is not available until
2196 explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL
2197 this is instead controlled by the value of
2198 /config/load-environment.
2199
Eric Nelsonf61ec452012-01-31 10:52:08 -07002200- Serial Flash support
Simon Glass00fd59d2017-08-04 16:35:06 -06002201 Usage requires an initial 'sf probe' to define the serial
Eric Nelsonf61ec452012-01-31 10:52:08 -07002202 flash parameters, followed by read/write/erase/update
2203 commands.
2204
2205 The following defaults may be provided by the platform
2206 to handle the common case when only a single serial
2207 flash is present on the system.
2208
2209 CONFIG_SF_DEFAULT_BUS Bus identifier
2210 CONFIG_SF_DEFAULT_CS Chip-select
2211 CONFIG_SF_DEFAULT_MODE (see include/spi.h)
2212 CONFIG_SF_DEFAULT_SPEED in Hz
2213
wdenk3f85ce22004-02-23 16:11:30 +00002214
Wolfgang Denkecb0ccd2005-09-24 22:37:32 +02002215- TFTP Fixed UDP Port:
2216 CONFIG_TFTP_PORT
2217
Wolfgang Denk28cb9372005-09-24 23:25:46 +02002218 If this is defined, the environment variable tftpsrcp
Wolfgang Denkecb0ccd2005-09-24 22:37:32 +02002219 is used to supply the TFTP UDP source port value.
Wolfgang Denk28cb9372005-09-24 23:25:46 +02002220 If tftpsrcp isn't defined, the normal pseudo-random port
Wolfgang Denkecb0ccd2005-09-24 22:37:32 +02002221 number generator is used.
2222
Wolfgang Denk28cb9372005-09-24 23:25:46 +02002223 Also, the environment variable tftpdstp is used to supply
2224 the TFTP UDP destination port value. If tftpdstp isn't
2225 defined, the normal port 69 is used.
2226
2227 The purpose for tftpsrcp is to allow a TFTP server to
Wolfgang Denkecb0ccd2005-09-24 22:37:32 +02002228 blindly start the TFTP transfer using the pre-configured
2229 target IP address and UDP port. This has the effect of
2230 "punching through" the (Windows XP) firewall, allowing
2231 the remainder of the TFTP transfer to proceed normally.
2232 A better solution is to properly configure the firewall,
2233 but sometimes that is not allowed.
2234
wdenka8c7c702003-12-06 19:49:23 +00002235- Show boot progress:
wdenkc6097192002-11-03 00:24:07 +00002236 CONFIG_SHOW_BOOT_PROGRESS
2237
wdenk43d96162003-03-06 00:02:04 +00002238 Defining this option allows to add some board-
2239 specific code (calling a user-provided function
2240 "show_boot_progress(int)") that enables you to show
2241 the system's boot progress on some display (for
2242 example, some LED's) on your board. At the moment,
2243 the following checkpoints are implemented:
wdenkc6097192002-11-03 00:24:07 +00002244
Simon Glass94fd1312012-09-28 08:56:37 +00002245
Marian Balakowicz1372cce2008-03-12 10:33:01 +01002246Legacy uImage format:
2247
wdenkc6097192002-11-03 00:24:07 +00002248 Arg Where When
2249 1 common/cmd_bootm.c before attempting to boot an image
wdenkba56f622004-02-06 23:19:44 +00002250 -1 common/cmd_bootm.c Image header has bad magic number
wdenkc6097192002-11-03 00:24:07 +00002251 2 common/cmd_bootm.c Image header has correct magic number
wdenkba56f622004-02-06 23:19:44 +00002252 -2 common/cmd_bootm.c Image header has bad checksum
wdenkc6097192002-11-03 00:24:07 +00002253 3 common/cmd_bootm.c Image header has correct checksum
wdenkba56f622004-02-06 23:19:44 +00002254 -3 common/cmd_bootm.c Image data has bad checksum
wdenkc6097192002-11-03 00:24:07 +00002255 4 common/cmd_bootm.c Image data has correct checksum
2256 -4 common/cmd_bootm.c Image is for unsupported architecture
2257 5 common/cmd_bootm.c Architecture check OK
Marian Balakowicz1372cce2008-03-12 10:33:01 +01002258 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi)
wdenkc6097192002-11-03 00:24:07 +00002259 6 common/cmd_bootm.c Image Type check OK
2260 -6 common/cmd_bootm.c gunzip uncompression error
2261 -7 common/cmd_bootm.c Unimplemented compression type
2262 7 common/cmd_bootm.c Uncompression OK
Marian Balakowicz1372cce2008-03-12 10:33:01 +01002263 8 common/cmd_bootm.c No uncompress/copy overwrite error
wdenkc6097192002-11-03 00:24:07 +00002264 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
Marian Balakowicz1372cce2008-03-12 10:33:01 +01002265
2266 9 common/image.c Start initial ramdisk verification
2267 -10 common/image.c Ramdisk header has bad magic number
2268 -11 common/image.c Ramdisk header has bad checksum
2269 10 common/image.c Ramdisk header is OK
2270 -12 common/image.c Ramdisk data has bad checksum
2271 11 common/image.c Ramdisk data has correct checksum
2272 12 common/image.c Ramdisk verification complete, start loading
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002273 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk)
Marian Balakowicz1372cce2008-03-12 10:33:01 +01002274 13 common/image.c Start multifile image verification
2275 14 common/image.c No initial ramdisk, no multifile, continue.
2276
Wolfgang Denkc0f40852011-10-26 10:21:21 +00002277 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS
wdenkc6097192002-11-03 00:24:07 +00002278
Stefan Roesea47a12b2010-04-15 16:07:28 +02002279 -30 arch/powerpc/lib/board.c Fatal error, hang the system
wdenk11dadd52004-02-27 00:07:27 +00002280 -31 post/post.c POST test failed, detected by post_output_backlog()
2281 -32 post/post.c POST test failed, detected by post_run_single()
wdenk63e73c92004-02-23 22:22:28 +00002282
Heiko Schocher566a4942007-06-22 19:11:54 +02002283 34 common/cmd_doc.c before loading a Image from a DOC device
2284 -35 common/cmd_doc.c Bad usage of "doc" command
2285 35 common/cmd_doc.c correct usage of "doc" command
2286 -36 common/cmd_doc.c No boot device
2287 36 common/cmd_doc.c correct boot device
2288 -37 common/cmd_doc.c Unknown Chip ID on boot device
2289 37 common/cmd_doc.c correct chip ID found, device available
2290 -38 common/cmd_doc.c Read Error on boot device
2291 38 common/cmd_doc.c reading Image header from DOC device OK
2292 -39 common/cmd_doc.c Image header has bad magic number
2293 39 common/cmd_doc.c Image header has correct magic number
2294 -40 common/cmd_doc.c Error reading Image from DOC device
2295 40 common/cmd_doc.c Image header has correct magic number
2296 41 common/cmd_ide.c before loading a Image from a IDE device
2297 -42 common/cmd_ide.c Bad usage of "ide" command
2298 42 common/cmd_ide.c correct usage of "ide" command
2299 -43 common/cmd_ide.c No boot device
2300 43 common/cmd_ide.c boot device found
2301 -44 common/cmd_ide.c Device not available
2302 44 common/cmd_ide.c Device available
2303 -45 common/cmd_ide.c wrong partition selected
2304 45 common/cmd_ide.c partition selected
2305 -46 common/cmd_ide.c Unknown partition table
2306 46 common/cmd_ide.c valid partition table found
2307 -47 common/cmd_ide.c Invalid partition type
2308 47 common/cmd_ide.c correct partition type
2309 -48 common/cmd_ide.c Error reading Image Header on boot device
2310 48 common/cmd_ide.c reading Image Header from IDE device OK
2311 -49 common/cmd_ide.c Image header has bad magic number
2312 49 common/cmd_ide.c Image header has correct magic number
2313 -50 common/cmd_ide.c Image header has bad checksum
2314 50 common/cmd_ide.c Image header has correct checksum
2315 -51 common/cmd_ide.c Error reading Image from IDE device
2316 51 common/cmd_ide.c reading Image from IDE device OK
2317 52 common/cmd_nand.c before loading a Image from a NAND device
2318 -53 common/cmd_nand.c Bad usage of "nand" command
2319 53 common/cmd_nand.c correct usage of "nand" command
2320 -54 common/cmd_nand.c No boot device
2321 54 common/cmd_nand.c boot device found
2322 -55 common/cmd_nand.c Unknown Chip ID on boot device
2323 55 common/cmd_nand.c correct chip ID found, device available
2324 -56 common/cmd_nand.c Error reading Image Header on boot device
2325 56 common/cmd_nand.c reading Image Header from NAND device OK
2326 -57 common/cmd_nand.c Image header has bad magic number
2327 57 common/cmd_nand.c Image header has correct magic number
2328 -58 common/cmd_nand.c Error reading Image from NAND device
2329 58 common/cmd_nand.c reading Image from NAND device OK
wdenkc6097192002-11-03 00:24:07 +00002330
Heiko Schocher566a4942007-06-22 19:11:54 +02002331 -60 common/env_common.c Environment has a bad CRC, using default
wdenkc6097192002-11-03 00:24:07 +00002332
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002333 64 net/eth.c starting with Ethernet configuration.
Heiko Schocher566a4942007-06-22 19:11:54 +02002334 -64 net/eth.c no Ethernet found.
2335 65 net/eth.c Ethernet found.
wdenk206c60c2003-09-18 10:02:25 +00002336
Heiko Schocher566a4942007-06-22 19:11:54 +02002337 -80 common/cmd_net.c usage wrong
Joe Hershbergerbc0571f2015-04-08 01:41:21 -05002338 80 common/cmd_net.c before calling net_loop()
2339 -81 common/cmd_net.c some error in net_loop() occurred
2340 81 common/cmd_net.c net_loop() back without error
Heiko Schocher566a4942007-06-22 19:11:54 +02002341 -82 common/cmd_net.c size == 0 (File with size 0 loaded)
2342 82 common/cmd_net.c trying automatic boot
Wolfgang Denk74de7ae2009-04-01 23:34:12 +02002343 83 common/cmd_net.c running "source" command
2344 -83 common/cmd_net.c some error in automatic boot or "source" command
Heiko Schocher566a4942007-06-22 19:11:54 +02002345 84 common/cmd_net.c end without errors
wdenkc6097192002-11-03 00:24:07 +00002346
Marian Balakowicz1372cce2008-03-12 10:33:01 +01002347FIT uImage format:
2348
2349 Arg Where When
2350 100 common/cmd_bootm.c Kernel FIT Image has correct format
2351 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format
2352 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration
2353 -101 common/cmd_bootm.c Can't get configuration for kernel subimage
2354 102 common/cmd_bootm.c Kernel unit name specified
2355 -103 common/cmd_bootm.c Can't get kernel subimage node offset
Marian Balakowiczf773bea2008-03-12 10:35:46 +01002356 103 common/cmd_bootm.c Found configuration node
Marian Balakowicz1372cce2008-03-12 10:33:01 +01002357 104 common/cmd_bootm.c Got kernel subimage node offset
2358 -104 common/cmd_bootm.c Kernel subimage hash verification failed
2359 105 common/cmd_bootm.c Kernel subimage hash verification OK
2360 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture
2361 106 common/cmd_bootm.c Architecture check OK
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002362 -106 common/cmd_bootm.c Kernel subimage has wrong type
2363 107 common/cmd_bootm.c Kernel subimage type OK
Marian Balakowicz1372cce2008-03-12 10:33:01 +01002364 -107 common/cmd_bootm.c Can't get kernel subimage data/size
2365 108 common/cmd_bootm.c Got kernel subimage data/size
2366 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT)
2367 -109 common/cmd_bootm.c Can't get kernel subimage type
2368 -110 common/cmd_bootm.c Can't get kernel subimage comp
2369 -111 common/cmd_bootm.c Can't get kernel subimage os
2370 -112 common/cmd_bootm.c Can't get kernel subimage load address
2371 -113 common/cmd_bootm.c Image uncompress/copy overwrite error
2372
2373 120 common/image.c Start initial ramdisk verification
2374 -120 common/image.c Ramdisk FIT image has incorrect format
2375 121 common/image.c Ramdisk FIT image has correct format
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002376 122 common/image.c No ramdisk subimage unit name, using configuration
Marian Balakowicz1372cce2008-03-12 10:33:01 +01002377 -122 common/image.c Can't get configuration for ramdisk subimage
2378 123 common/image.c Ramdisk unit name specified
2379 -124 common/image.c Can't get ramdisk subimage node offset
2380 125 common/image.c Got ramdisk subimage node offset
2381 -125 common/image.c Ramdisk subimage hash verification failed
2382 126 common/image.c Ramdisk subimage hash verification OK
2383 -126 common/image.c Ramdisk subimage for unsupported architecture
2384 127 common/image.c Architecture check OK
2385 -127 common/image.c Can't get ramdisk subimage data/size
2386 128 common/image.c Got ramdisk subimage data/size
2387 129 common/image.c Can't get ramdisk load address
2388 -129 common/image.c Got ramdisk load address
2389
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002390 -130 common/cmd_doc.c Incorrect FIT image format
Marian Balakowicz1372cce2008-03-12 10:33:01 +01002391 131 common/cmd_doc.c FIT image format OK
2392
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002393 -140 common/cmd_ide.c Incorrect FIT image format
Marian Balakowicz1372cce2008-03-12 10:33:01 +01002394 141 common/cmd_ide.c FIT image format OK
2395
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002396 -150 common/cmd_nand.c Incorrect FIT image format
Marian Balakowicz1372cce2008-03-12 10:33:01 +01002397 151 common/cmd_nand.c FIT image format OK
2398
Wolfgang Denk4cf26092011-10-07 09:58:21 +02002399- Standalone program support:
2400 CONFIG_STANDALONE_LOAD_ADDR
2401
Wolfgang Denk6feff892011-10-09 21:06:34 +02002402 This option defines a board specific value for the
2403 address where standalone program gets loaded, thus
2404 overwriting the architecture dependent default
Wolfgang Denk4cf26092011-10-07 09:58:21 +02002405 settings.
2406
2407- Frame Buffer Address:
2408 CONFIG_FB_ADDR
2409
2410 Define CONFIG_FB_ADDR if you want to use specific
Wolfgang Denk44a53b52013-01-03 00:43:59 +00002411 address for frame buffer. This is typically the case
2412 when using a graphics controller has separate video
2413 memory. U-Boot will then place the frame buffer at
2414 the given address instead of dynamically reserving it
2415 in system RAM by calling lcd_setmem(), which grabs
2416 the memory for the frame buffer depending on the
2417 configured panel size.
Wolfgang Denk4cf26092011-10-07 09:58:21 +02002418
2419 Please see board_init_f function.
2420
Detlev Zundelcccfc2a2009-12-01 17:16:19 +01002421- Automatic software updates via TFTP server
2422 CONFIG_UPDATE_TFTP
2423 CONFIG_UPDATE_TFTP_CNT_MAX
2424 CONFIG_UPDATE_TFTP_MSEC_MAX
2425
2426 These options enable and control the auto-update feature;
2427 for a more detailed description refer to doc/README.update.
2428
2429- MTD Support (mtdparts command, UBI support)
Heiko Schocherff94bc42014-06-24 10:10:04 +02002430 CONFIG_MTD_UBI_WL_THRESHOLD
2431 This parameter defines the maximum difference between the highest
2432 erase counter value and the lowest erase counter value of eraseblocks
2433 of UBI devices. When this threshold is exceeded, UBI starts performing
2434 wear leveling by means of moving data from eraseblock with low erase
2435 counter to eraseblocks with high erase counter.
2436
2437 The default value should be OK for SLC NAND flashes, NOR flashes and
2438 other flashes which have eraseblock life-cycle 100000 or more.
2439 However, in case of MLC NAND flashes which typically have eraseblock
2440 life-cycle less than 10000, the threshold should be lessened (e.g.,
2441 to 128 or 256, although it does not have to be power of 2).
2442
2443 default: 4096
Simon Glassc654b512014-10-23 18:58:54 -06002444
Heiko Schocherff94bc42014-06-24 10:10:04 +02002445 CONFIG_MTD_UBI_BEB_LIMIT
2446 This option specifies the maximum bad physical eraseblocks UBI
2447 expects on the MTD device (per 1024 eraseblocks). If the
2448 underlying flash does not admit of bad eraseblocks (e.g. NOR
2449 flash), this value is ignored.
2450
2451 NAND datasheets often specify the minimum and maximum NVM
2452 (Number of Valid Blocks) for the flashes' endurance lifetime.
2453 The maximum expected bad eraseblocks per 1024 eraseblocks
2454 then can be calculated as "1024 * (1 - MinNVB / MaxNVB)",
2455 which gives 20 for most NANDs (MaxNVB is basically the total
2456 count of eraseblocks on the chip).
2457
2458 To put it differently, if this value is 20, UBI will try to
2459 reserve about 1.9% of physical eraseblocks for bad blocks
2460 handling. And that will be 1.9% of eraseblocks on the entire
2461 NAND chip, not just the MTD partition UBI attaches. This means
2462 that if you have, say, a NAND flash chip admits maximum 40 bad
2463 eraseblocks, and it is split on two MTD partitions of the same
2464 size, UBI will reserve 40 eraseblocks when attaching a
2465 partition.
2466
2467 default: 20
2468
2469 CONFIG_MTD_UBI_FASTMAP
2470 Fastmap is a mechanism which allows attaching an UBI device
2471 in nearly constant time. Instead of scanning the whole MTD device it
2472 only has to locate a checkpoint (called fastmap) on the device.
2473 The on-flash fastmap contains all information needed to attach
2474 the device. Using fastmap makes only sense on large devices where
2475 attaching by scanning takes long. UBI will not automatically install
2476 a fastmap on old images, but you can set the UBI parameter
2477 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT to 1 if you want so. Please note
2478 that fastmap-enabled images are still usable with UBI implementations
2479 without fastmap support. On typical flash devices the whole fastmap
2480 fits into one PEB. UBI will reserve PEBs to hold two fastmaps.
2481
2482 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT
2483 Set this parameter to enable fastmap automatically on images
2484 without a fastmap.
2485 default: 0
2486
Heiko Schocher0195a7b2015-10-22 06:19:21 +02002487 CONFIG_MTD_UBI_FM_DEBUG
2488 Enable UBI fastmap debug
2489 default: 0
2490
Daniel Schwierzeck6a11cf42011-07-18 07:48:07 +00002491- SPL framework
Wolfgang Denk04e5ae72011-09-11 21:24:09 +02002492 CONFIG_SPL
2493 Enable building of SPL globally.
Daniel Schwierzeck6a11cf42011-07-18 07:48:07 +00002494
Tom Rini95579792012-02-14 07:29:40 +00002495 CONFIG_SPL_LDSCRIPT
2496 LDSCRIPT for linking the SPL binary.
2497
Albert ARIBAUD6ebc3462013-04-12 05:14:30 +00002498 CONFIG_SPL_MAX_FOOTPRINT
2499 Maximum size in memory allocated to the SPL, BSS included.
2500 When defined, the linker checks that the actual memory
2501 used by SPL from _start to __bss_end does not exceed it.
Albert ARIBAUD8960af82013-04-14 04:48:38 +00002502 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
Albert ARIBAUD6ebc3462013-04-12 05:14:30 +00002503 must not be both defined at the same time.
2504
Tom Rini95579792012-02-14 07:29:40 +00002505 CONFIG_SPL_MAX_SIZE
Albert ARIBAUD6ebc3462013-04-12 05:14:30 +00002506 Maximum size of the SPL image (text, data, rodata, and
2507 linker lists sections), BSS excluded.
2508 When defined, the linker checks that the actual size does
2509 not exceed it.
Tom Rini95579792012-02-14 07:29:40 +00002510
Wolfgang Denk04e5ae72011-09-11 21:24:09 +02002511 CONFIG_SPL_TEXT_BASE
2512 TEXT_BASE for linking the SPL binary.
Daniel Schwierzeck6a11cf42011-07-18 07:48:07 +00002513
Scott Wood94a45bb2012-09-20 19:05:12 -05002514 CONFIG_SPL_RELOC_TEXT_BASE
2515 Address to relocate to. If unspecified, this is equal to
2516 CONFIG_SPL_TEXT_BASE (i.e. no relocation is done).
2517
Tom Rini95579792012-02-14 07:29:40 +00002518 CONFIG_SPL_BSS_START_ADDR
2519 Link address for the BSS within the SPL binary.
2520
2521 CONFIG_SPL_BSS_MAX_SIZE
Albert ARIBAUD6ebc3462013-04-12 05:14:30 +00002522 Maximum size in memory allocated to the SPL BSS.
2523 When defined, the linker checks that the actual memory used
2524 by SPL from __bss_start to __bss_end does not exceed it.
Albert ARIBAUD8960af82013-04-14 04:48:38 +00002525 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
Albert ARIBAUD6ebc3462013-04-12 05:14:30 +00002526 must not be both defined at the same time.
Tom Rini95579792012-02-14 07:29:40 +00002527
2528 CONFIG_SPL_STACK
2529 Adress of the start of the stack SPL will use
2530
Albert ARIBAUD \(3ADEV\)8c80eb32015-03-31 11:40:50 +02002531 CONFIG_SPL_PANIC_ON_RAW_IMAGE
2532 When defined, SPL will panic() if the image it has
2533 loaded does not have a signature.
2534 Defining this is useful when code which loads images
2535 in SPL cannot guarantee that absolutely all read errors
2536 will be caught.
2537 An example is the LPC32XX MLC NAND driver, which will
2538 consider that a completely unreadable NAND block is bad,
2539 and thus should be skipped silently.
2540
Scott Wood94a45bb2012-09-20 19:05:12 -05002541 CONFIG_SPL_RELOC_STACK
2542 Adress of the start of the stack SPL will use after
2543 relocation. If unspecified, this is equal to
2544 CONFIG_SPL_STACK.
2545
Tom Rini95579792012-02-14 07:29:40 +00002546 CONFIG_SYS_SPL_MALLOC_START
2547 Starting address of the malloc pool used in SPL.
Fabio Estevam9ac4fc82015-11-12 12:30:19 -02002548 When this option is set the full malloc is used in SPL and
2549 it is set up by spl_init() and before that, the simple malloc()
2550 can be used if CONFIG_SYS_MALLOC_F is defined.
Tom Rini95579792012-02-14 07:29:40 +00002551
2552 CONFIG_SYS_SPL_MALLOC_SIZE
2553 The size of the malloc pool used in SPL.
Daniel Schwierzeck6a11cf42011-07-18 07:48:07 +00002554
Tom Rini9607faf2014-03-28 12:03:39 -04002555 CONFIG_SPL_OS_BOOT
2556 Enable booting directly to an OS from SPL.
2557 See also: doc/README.falcon
2558
Tom Rini861a86f2012-08-13 11:37:56 -07002559 CONFIG_SPL_DISPLAY_PRINT
2560 For ARM, enable an optional function to print more information
2561 about the running system.
2562
Scott Wood4b919722012-09-20 16:35:21 -05002563 CONFIG_SPL_INIT_MINIMAL
2564 Arch init code should be built for a very small image
2565
Paul Kocialkowskib97300b2014-11-08 23:14:56 +01002566 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_PARTITION
2567 Partition on the MMC to load U-Boot from when the MMC is being
2568 used in raw mode
2569
Peter Korsgaard2b75b0a2013-05-13 08:36:29 +00002570 CONFIG_SYS_MMCSD_RAW_MODE_KERNEL_SECTOR
2571 Sector to load kernel uImage from when MMC is being
2572 used in raw mode (for Falcon mode)
2573
2574 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTOR,
2575 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTORS
2576 Sector and number of sectors to load kernel argument
2577 parameters from when MMC is being used in raw mode
2578 (for falcon mode)
2579
Paul Kocialkowskie2ccdf82014-11-08 23:14:55 +01002580 CONFIG_SYS_MMCSD_FS_BOOT_PARTITION
2581 Partition on the MMC to load U-Boot from when the MMC is being
2582 used in fs mode
2583
Guillaume GARDETfae81c72014-10-15 17:53:13 +02002584 CONFIG_SPL_FS_LOAD_PAYLOAD_NAME
2585 Filename to read to load U-Boot when reading from filesystem
2586
2587 CONFIG_SPL_FS_LOAD_KERNEL_NAME
Peter Korsgaard7ad2cc72013-05-13 08:36:27 +00002588 Filename to read to load kernel uImage when reading
Guillaume GARDETfae81c72014-10-15 17:53:13 +02002589 from filesystem (for Falcon mode)
Peter Korsgaard7ad2cc72013-05-13 08:36:27 +00002590
Guillaume GARDETfae81c72014-10-15 17:53:13 +02002591 CONFIG_SPL_FS_LOAD_ARGS_NAME
Peter Korsgaard7ad2cc72013-05-13 08:36:27 +00002592 Filename to read to load kernel argument parameters
Guillaume GARDETfae81c72014-10-15 17:53:13 +02002593 when reading from filesystem (for Falcon mode)
Peter Korsgaard7ad2cc72013-05-13 08:36:27 +00002594
Scott Wood06f60ae2012-12-06 13:33:17 +00002595 CONFIG_SPL_MPC83XX_WAIT_FOR_NAND
2596 Set this for NAND SPL on PPC mpc83xx targets, so that
2597 start.S waits for the rest of the SPL to load before
2598 continuing (the hardware starts execution after just
2599 loading the first page rather than the full 4K).
2600
Prabhakar Kushwaha651fcf62014-04-08 19:12:31 +05302601 CONFIG_SPL_SKIP_RELOCATE
2602 Avoid SPL relocation
2603
Scott Wood6f2f01b2012-09-20 19:09:07 -05002604 CONFIG_SPL_NAND_BASE
2605 Include nand_base.c in the SPL. Requires
2606 CONFIG_SPL_NAND_DRIVERS.
2607
2608 CONFIG_SPL_NAND_DRIVERS
2609 SPL uses normal NAND drivers, not minimal drivers.
2610
Jörg Krause15e207f2018-01-14 19:26:38 +01002611 CONFIG_SPL_NAND_IDENT
2612 SPL uses the chip ID list to identify the NAND flash.
2613 Requires CONFIG_SPL_NAND_BASE.
2614
Scott Wood6f2f01b2012-09-20 19:09:07 -05002615 CONFIG_SPL_NAND_ECC
2616 Include standard software ECC in the SPL
2617
Tom Rini95579792012-02-14 07:29:40 +00002618 CONFIG_SPL_NAND_SIMPLE
Scott Wood7d4b7952012-09-21 18:35:27 -05002619 Support for NAND boot using simple NAND drivers that
2620 expose the cmd_ctrl() interface.
Tom Rini95579792012-02-14 07:29:40 +00002621
Thomas Gleixner6f4e7d32016-07-12 20:28:12 +02002622 CONFIG_SPL_UBI
2623 Support for a lightweight UBI (fastmap) scanner and
2624 loader
2625
Heiko Schocher0c3117b2014-10-31 08:31:00 +01002626 CONFIG_SPL_NAND_RAW_ONLY
2627 Support to boot only raw u-boot.bin images. Use this only
2628 if you need to save space.
2629
Ying Zhang7c8eea52013-08-16 15:16:12 +08002630 CONFIG_SPL_COMMON_INIT_DDR
2631 Set for common ddr init with serial presence detect in
2632 SPL binary.
2633
Tom Rini95579792012-02-14 07:29:40 +00002634 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT,
2635 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE,
2636 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS,
2637 CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE,
2638 CONFIG_SYS_NAND_ECCBYTES
2639 Defines the size and behavior of the NAND that SPL uses
Scott Wood7d4b7952012-09-21 18:35:27 -05002640 to read U-Boot
Tom Rini95579792012-02-14 07:29:40 +00002641
Prabhakar Kushwahafbe76ae2013-12-11 12:42:11 +05302642 CONFIG_SPL_NAND_BOOT
2643 Add support NAND boot
2644
Tom Rini95579792012-02-14 07:29:40 +00002645 CONFIG_SYS_NAND_U_BOOT_OFFS
Scott Wood7d4b7952012-09-21 18:35:27 -05002646 Location in NAND to read U-Boot from
2647
2648 CONFIG_SYS_NAND_U_BOOT_DST
2649 Location in memory to load U-Boot to
2650
2651 CONFIG_SYS_NAND_U_BOOT_SIZE
2652 Size of image to load
Tom Rini95579792012-02-14 07:29:40 +00002653
2654 CONFIG_SYS_NAND_U_BOOT_START
Scott Wood7d4b7952012-09-21 18:35:27 -05002655 Entry point in loaded image to jump to
Tom Rini95579792012-02-14 07:29:40 +00002656
2657 CONFIG_SYS_NAND_HW_ECC_OOBFIRST
2658 Define this if you need to first read the OOB and then the
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08002659 data. This is used, for example, on davinci platforms.
Tom Rini95579792012-02-14 07:29:40 +00002660
Pavel Machekc57b9532012-08-30 22:42:11 +02002661 CONFIG_SPL_RAM_DEVICE
2662 Support for running image already present in ram, in SPL binary
2663
Scott Wood74752ba2012-12-06 13:33:16 +00002664 CONFIG_SPL_PAD_TO
Benoît Thébaudeau6113d3f2013-04-11 09:35:49 +00002665 Image offset to which the SPL should be padded before appending
2666 the SPL payload. By default, this is defined as
2667 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
2668 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
2669 payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
Scott Wood74752ba2012-12-06 13:33:16 +00002670
Scott Woodca2fca22012-09-21 16:27:32 -05002671 CONFIG_SPL_TARGET
2672 Final target image containing SPL and payload. Some SPLs
2673 use an arch-specific makefile fragment instead, for
2674 example if more than one image needs to be produced.
2675
Marek Vasutb527b9c2018-05-13 00:22:52 +02002676 CONFIG_SPL_FIT_PRINT
Simon Glass87ebee32013-05-08 08:05:59 +00002677 Printing information about a FIT image adds quite a bit of
2678 code to SPL. So this is normally disabled in SPL. Use this
2679 option to re-enable it. This will affect the output of the
2680 bootm command when booting a FIT image.
2681
Ying Zhang3aa29de2013-08-16 15:16:15 +08002682- TPL framework
2683 CONFIG_TPL
2684 Enable building of TPL globally.
2685
2686 CONFIG_TPL_PAD_TO
2687 Image offset to which the TPL should be padded before appending
2688 the TPL payload. By default, this is defined as
Wolfgang Denk93e14592013-10-04 17:43:24 +02002689 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
2690 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
2691 payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
Ying Zhang3aa29de2013-08-16 15:16:15 +08002692
wdenka8c7c702003-12-06 19:49:23 +00002693- Interrupt support (PPC):
2694
wdenkd4ca31c2004-01-02 14:00:00 +00002695 There are common interrupt_init() and timer_interrupt()
2696 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002697 for CPU specific initialization. interrupt_init_cpu()
wdenkd4ca31c2004-01-02 14:00:00 +00002698 should set decrementer_count to appropriate value. If
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002699 CPU resets decrementer automatically after interrupt
wdenkd4ca31c2004-01-02 14:00:00 +00002700 (ppc4xx) it should set decrementer_count to zero.
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002701 timer_interrupt() calls timer_interrupt_cpu() for CPU
wdenkd4ca31c2004-01-02 14:00:00 +00002702 specific handling. If board has watchdog / status_led
2703 / other_activity_monitor it works automatically from
2704 general timer_interrupt().
wdenka8c7c702003-12-06 19:49:23 +00002705
wdenkc6097192002-11-03 00:24:07 +00002706
Helmut Raiger9660e442011-10-20 04:19:47 +00002707Board initialization settings:
2708------------------------------
2709
2710During Initialization u-boot calls a number of board specific functions
2711to allow the preparation of board specific prerequisites, e.g. pin setup
2712before drivers are initialized. To enable these callbacks the
2713following configuration macros have to be defined. Currently this is
2714architecture specific, so please check arch/your_architecture/lib/board.c
2715typically in board_init_f() and board_init_r().
2716
2717- CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f()
2718- CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r()
2719- CONFIG_BOARD_LATE_INIT: Call board_late_init()
2720- CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init()
wdenkc6097192002-11-03 00:24:07 +00002721
wdenkc6097192002-11-03 00:24:07 +00002722Configuration Settings:
2723-----------------------
2724
York Sun4d1fd7f2014-02-26 17:03:19 -08002725- CONFIG_SYS_SUPPORT_64BIT_DATA: Defined automatically if compiled as 64-bit.
2726 Optionally it can be defined to support 64-bit memory commands.
2727
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002728- CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
wdenkc6097192002-11-03 00:24:07 +00002729 undefine this when you're short of memory.
2730
Peter Tyser2fb26042009-01-27 18:03:12 -06002731- CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
2732 width of the commands listed in the 'help' command output.
2733
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002734- CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to
wdenkc6097192002-11-03 00:24:07 +00002735 prompt for user input.
2736
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002737- CONFIG_SYS_CBSIZE: Buffer size for input from the Console
wdenkc6097192002-11-03 00:24:07 +00002738
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002739- CONFIG_SYS_PBSIZE: Buffer size for Console output
wdenkc6097192002-11-03 00:24:07 +00002740
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002741- CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands
wdenkc6097192002-11-03 00:24:07 +00002742
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002743- CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to
wdenkc6097192002-11-03 00:24:07 +00002744 the application (usually a Linux kernel) when it is
2745 booted
2746
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002747- CONFIG_SYS_BAUDRATE_TABLE:
wdenkc6097192002-11-03 00:24:07 +00002748 List of legal baudrate settings for this board.
2749
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002750- CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END:
wdenkc6097192002-11-03 00:24:07 +00002751 Begin and End addresses of the area used by the
2752 simple memory test.
2753
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002754- CONFIG_SYS_MEMTEST_SCRATCH:
wdenk5f535fe2003-09-18 09:21:33 +00002755 Scratch address used by the alternate memory test
2756 You only need to set this if address zero isn't writeable
2757
York Sune8149522015-12-04 11:57:07 -08002758- CONFIG_SYS_MEM_RESERVE_SECURE
York Sune61a7532016-06-24 16:46:18 -07002759 Only implemented for ARMv8 for now.
York Sune8149522015-12-04 11:57:07 -08002760 If defined, the size of CONFIG_SYS_MEM_RESERVE_SECURE memory
2761 is substracted from total RAM and won't be reported to OS.
2762 This memory can be used as secure memory. A variable
York Sune61a7532016-06-24 16:46:18 -07002763 gd->arch.secure_ram is used to track the location. In systems
York Sune8149522015-12-04 11:57:07 -08002764 the RAM base is not zero, or RAM is divided into banks,
2765 this variable needs to be recalcuated to get the address.
2766
York Sunaabd7dd2015-12-07 11:05:29 -08002767- CONFIG_SYS_MEM_TOP_HIDE:
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002768 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header,
Stefan Roese14f73ca2008-03-26 10:14:11 +01002769 this specified memory area will get subtracted from the top
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002770 (end) of RAM and won't get "touched" at all by U-Boot. By
Stefan Roese14f73ca2008-03-26 10:14:11 +01002771 fixing up gd->ram_size the Linux kernel should gets passed
2772 the now "corrected" memory size and won't touch it either.
2773 This should work for arch/ppc and arch/powerpc. Only Linux
Stefan Roese5e12e752008-03-28 11:02:53 +01002774 board ports in arch/powerpc with bootwrapper support that
Stefan Roese14f73ca2008-03-26 10:14:11 +01002775 recalculate the memory size from the SDRAM controller setup
Stefan Roese5e12e752008-03-28 11:02:53 +01002776 will have to get fixed in Linux additionally.
Stefan Roese14f73ca2008-03-26 10:14:11 +01002777
2778 This option can be used as a workaround for the 440EPx/GRx
2779 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't
2780 be touched.
2781
2782 WARNING: Please make sure that this value is a multiple of
2783 the Linux page size (normally 4k). If this is not the case,
2784 then the end address of the Linux memory will be located at a
2785 non page size aligned address and this could cause major
2786 problems.
2787
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002788- CONFIG_SYS_LOADS_BAUD_CHANGE:
wdenkc6097192002-11-03 00:24:07 +00002789 Enable temporary baudrate change while serial download
2790
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002791- CONFIG_SYS_SDRAM_BASE:
wdenkc6097192002-11-03 00:24:07 +00002792 Physical start address of SDRAM. _Must_ be 0 here.
2793
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002794- CONFIG_SYS_FLASH_BASE:
wdenkc6097192002-11-03 00:24:07 +00002795 Physical start address of Flash memory.
2796
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002797- CONFIG_SYS_MONITOR_BASE:
wdenkc6097192002-11-03 00:24:07 +00002798 Physical start address of boot monitor code (set by
2799 make config files to be same as the text base address
Wolfgang Denk14d0a022010-10-07 21:51:12 +02002800 (CONFIG_SYS_TEXT_BASE) used when linking) - same as
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002801 CONFIG_SYS_FLASH_BASE when booting from flash.
wdenkc6097192002-11-03 00:24:07 +00002802
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002803- CONFIG_SYS_MONITOR_LEN:
wdenk8bde7f72003-06-27 21:31:46 +00002804 Size of memory reserved for monitor code, used to
2805 determine _at_compile_time_ (!) if the environment is
2806 embedded within the U-Boot image, or in a separate
2807 flash sector.
wdenkc6097192002-11-03 00:24:07 +00002808
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002809- CONFIG_SYS_MALLOC_LEN:
wdenkc6097192002-11-03 00:24:07 +00002810 Size of DRAM reserved for malloc() use.
2811
Simon Glassd59476b2014-07-10 22:23:28 -06002812- CONFIG_SYS_MALLOC_F_LEN
2813 Size of the malloc() pool for use before relocation. If
2814 this is defined, then a very simple malloc() implementation
2815 will become available before relocation. The address is just
2816 below the global data, and the stack is moved down to make
2817 space.
2818
2819 This feature allocates regions with increasing addresses
2820 within the region. calloc() is supported, but realloc()
2821 is not available. free() is supported but does nothing.
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08002822 The memory will be freed (or in fact just forgotten) when
Simon Glassd59476b2014-07-10 22:23:28 -06002823 U-Boot relocates itself.
2824
Simon Glass38687ae2014-11-10 17:16:54 -07002825- CONFIG_SYS_MALLOC_SIMPLE
2826 Provides a simple and small malloc() and calloc() for those
2827 boards which do not use the full malloc in SPL (which is
2828 enabled with CONFIG_SYS_SPL_MALLOC_START).
2829
Thierry Reding1dfdd9b2014-12-09 22:25:22 -07002830- CONFIG_SYS_NONCACHED_MEMORY:
2831 Size of non-cached memory area. This area of memory will be
2832 typically located right below the malloc() area and mapped
2833 uncached in the MMU. This is useful for drivers that would
2834 otherwise require a lot of explicit cache maintenance. For
2835 some drivers it's also impossible to properly maintain the
2836 cache. For example if the regions that need to be flushed
2837 are not a multiple of the cache-line size, *and* padding
2838 cannot be allocated between the regions to align them (i.e.
2839 if the HW requires a contiguous array of regions, and the
2840 size of each region is not cache-aligned), then a flush of
2841 one region may result in overwriting data that hardware has
2842 written to another region in the same cache-line. This can
2843 happen for example in network drivers where descriptors for
2844 buffers are typically smaller than the CPU cache-line (e.g.
2845 16 bytes vs. 32 or 64 bytes).
2846
2847 Non-cached memory is only supported on 32-bit ARM at present.
2848
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002849- CONFIG_SYS_BOOTM_LEN:
Stefan Roese15940c92006-03-13 11:16:36 +01002850 Normally compressed uImages are limited to an
2851 uncompressed size of 8 MBytes. If this is not enough,
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002852 you can define CONFIG_SYS_BOOTM_LEN in your board config file
Stefan Roese15940c92006-03-13 11:16:36 +01002853 to adjust this setting to your needs.
2854
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002855- CONFIG_SYS_BOOTMAPSZ:
wdenkc6097192002-11-03 00:24:07 +00002856 Maximum size of memory mapped by the startup code of
2857 the Linux kernel; all data that must be processed by
Bartlomiej Sieka7d721e32008-04-14 15:44:16 +02002858 the Linux kernel (bd_info, boot arguments, FDT blob if
2859 used) must be put below this limit, unless "bootm_low"
Robert P. J. Day1bce2ae2013-09-16 07:15:45 -04002860 environment variable is defined and non-zero. In such case
Bartlomiej Sieka7d721e32008-04-14 15:44:16 +02002861 all data for the Linux kernel must be between "bootm_low"
Wolfgang Denkc0f40852011-10-26 10:21:21 +00002862 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment
Grant Likelyc3624e62011-03-28 09:58:43 +00002863 variable "bootm_mapsize" will override the value of
2864 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined,
2865 then the value in "bootm_size" will be used instead.
wdenkc6097192002-11-03 00:24:07 +00002866
John Rigbyfca43cc2010-10-13 13:57:35 -06002867- CONFIG_SYS_BOOT_RAMDISK_HIGH:
2868 Enable initrd_high functionality. If defined then the
2869 initrd_high feature is enabled and the bootm ramdisk subcommand
2870 is enabled.
2871
2872- CONFIG_SYS_BOOT_GET_CMDLINE:
2873 Enables allocating and saving kernel cmdline in space between
2874 "bootm_low" and "bootm_low" + BOOTMAPSZ.
2875
2876- CONFIG_SYS_BOOT_GET_KBD:
2877 Enables allocating and saving a kernel copy of the bd_info in
2878 space between "bootm_low" and "bootm_low" + BOOTMAPSZ.
2879
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002880- CONFIG_SYS_MAX_FLASH_BANKS:
wdenkc6097192002-11-03 00:24:07 +00002881 Max number of Flash memory banks
2882
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002883- CONFIG_SYS_MAX_FLASH_SECT:
wdenkc6097192002-11-03 00:24:07 +00002884 Max number of sectors on a Flash chip
2885
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002886- CONFIG_SYS_FLASH_ERASE_TOUT:
wdenkc6097192002-11-03 00:24:07 +00002887 Timeout for Flash erase operations (in ms)
2888
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002889- CONFIG_SYS_FLASH_WRITE_TOUT:
wdenkc6097192002-11-03 00:24:07 +00002890 Timeout for Flash write operations (in ms)
2891
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002892- CONFIG_SYS_FLASH_LOCK_TOUT
wdenk8564acf2003-07-14 22:13:32 +00002893 Timeout for Flash set sector lock bit operation (in ms)
2894
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002895- CONFIG_SYS_FLASH_UNLOCK_TOUT
wdenk8564acf2003-07-14 22:13:32 +00002896 Timeout for Flash clear lock bits operation (in ms)
2897
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002898- CONFIG_SYS_FLASH_PROTECTION
wdenk8564acf2003-07-14 22:13:32 +00002899 If defined, hardware flash sectors protection is used
2900 instead of U-Boot software protection.
2901
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002902- CONFIG_SYS_DIRECT_FLASH_TFTP:
wdenkc6097192002-11-03 00:24:07 +00002903
2904 Enable TFTP transfers directly to flash memory;
2905 without this option such a download has to be
2906 performed in two steps: (1) download to RAM, and (2)
2907 copy from RAM to flash.
2908
2909 The two-step approach is usually more reliable, since
2910 you can check if the download worked before you erase
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002911 the flash, but in some situations (when system RAM is
2912 too limited to allow for a temporary copy of the
wdenkc6097192002-11-03 00:24:07 +00002913 downloaded image) this option may be very useful.
2914
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002915- CONFIG_SYS_FLASH_CFI:
wdenk43d96162003-03-06 00:02:04 +00002916 Define if the flash driver uses extra elements in the
wdenk5653fc32004-02-08 22:55:38 +00002917 common flash structure for storing flash geometry.
2918
Jean-Christophe PLAGNIOL-VILLARD00b18832008-08-13 01:40:42 +02002919- CONFIG_FLASH_CFI_DRIVER
wdenk5653fc32004-02-08 22:55:38 +00002920 This option also enables the building of the cfi_flash driver
2921 in the drivers directory
wdenkc6097192002-11-03 00:24:07 +00002922
Piotr Ziecik91809ed2008-11-17 15:57:58 +01002923- CONFIG_FLASH_CFI_MTD
2924 This option enables the building of the cfi_mtd driver
2925 in the drivers directory. The driver exports CFI flash
2926 to the MTD layer.
2927
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002928- CONFIG_SYS_FLASH_USE_BUFFER_WRITE
Guennadi Liakhovetski96ef8312008-04-03 13:36:02 +02002929 Use buffered writes to flash.
2930
2931- CONFIG_FLASH_SPANSION_S29WS_N
2932 s29ws-n MirrorBit flash has non-standard addresses for buffered
2933 write commands.
2934
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002935- CONFIG_SYS_FLASH_QUIET_TEST
Stefan Roese5568e612005-11-22 13:20:42 +01002936 If this option is defined, the common CFI flash doesn't
2937 print it's warning upon not recognized FLASH banks. This
2938 is useful, if some of the configured banks are only
2939 optionally available.
2940
Jerry Van Baren9a042e92008-03-08 13:48:01 -05002941- CONFIG_FLASH_SHOW_PROGRESS
2942 If defined (must be an integer), print out countdown
2943 digits and dots. Recommended value: 45 (9..1) for 80
2944 column displays, 15 (3..1) for 40 column displays.
2945
Stefan Roese352ef3f2013-04-04 15:53:14 +02002946- CONFIG_FLASH_VERIFY
2947 If defined, the content of the flash (destination) is compared
2948 against the source after the write operation. An error message
2949 will be printed when the contents are not identical.
2950 Please note that this option is useless in nearly all cases,
2951 since such flash programming errors usually are detected earlier
2952 while unprotecting/erasing/programming. Please only enable
2953 this option if you really know what you are doing.
2954
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002955- CONFIG_SYS_RX_ETH_BUFFER:
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002956 Defines the number of Ethernet receive buffers. On some
2957 Ethernet controllers it is recommended to set this value
stroese53cf9432003-06-05 15:39:44 +00002958 to 8 or even higher (EEPRO100 or 405 EMAC), since all
2959 buffers can be full shortly after enabling the interface
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002960 on high Ethernet traffic.
stroese53cf9432003-06-05 15:39:44 +00002961 Defaults to 4 if not defined.
2962
Wolfgang Denkea882ba2010-06-20 23:33:59 +02002963- CONFIG_ENV_MAX_ENTRIES
2964
Wolfgang Denk071bc922010-10-27 22:48:30 +02002965 Maximum number of entries in the hash table that is used
2966 internally to store the environment settings. The default
2967 setting is supposed to be generous and should work in most
2968 cases. This setting can be used to tune behaviour; see
2969 lib/hashtable.c for details.
Wolfgang Denkea882ba2010-06-20 23:33:59 +02002970
Joe Hershberger25980902012-12-11 22:16:31 -06002971- CONFIG_ENV_FLAGS_LIST_DEFAULT
2972- CONFIG_ENV_FLAGS_LIST_STATIC
Robert P. J. Day1bce2ae2013-09-16 07:15:45 -04002973 Enable validation of the values given to environment variables when
Joe Hershberger25980902012-12-11 22:16:31 -06002974 calling env set. Variables can be restricted to only decimal,
2975 hexadecimal, or boolean. If CONFIG_CMD_NET is also defined,
2976 the variables can also be restricted to IP address or MAC address.
2977
2978 The format of the list is:
2979 type_attribute = [s|d|x|b|i|m]
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08002980 access_attribute = [a|r|o|c]
2981 attributes = type_attribute[access_attribute]
Joe Hershberger25980902012-12-11 22:16:31 -06002982 entry = variable_name[:attributes]
2983 list = entry[,list]
2984
2985 The type attributes are:
2986 s - String (default)
2987 d - Decimal
2988 x - Hexadecimal
2989 b - Boolean ([1yYtT|0nNfF])
2990 i - IP address
2991 m - MAC address
2992
Joe Hershberger267541f2012-12-11 22:16:34 -06002993 The access attributes are:
2994 a - Any (default)
2995 r - Read-only
2996 o - Write-once
2997 c - Change-default
2998
Joe Hershberger25980902012-12-11 22:16:31 -06002999 - CONFIG_ENV_FLAGS_LIST_DEFAULT
3000 Define this to a list (string) to define the ".flags"
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08003001 environment variable in the default or embedded environment.
Joe Hershberger25980902012-12-11 22:16:31 -06003002
3003 - CONFIG_ENV_FLAGS_LIST_STATIC
3004 Define this to a list (string) to define validation that
3005 should be done if an entry is not found in the ".flags"
3006 environment variable. To override a setting in the static
3007 list, simply add an entry for the same variable name to the
3008 ".flags" variable.
3009
Joe Hershbergerbdf1fe42015-05-20 14:27:20 -05003010 If CONFIG_REGEX is defined, the variable_name above is evaluated as a
3011 regular expression. This allows multiple variables to define the same
3012 flags without explicitly listing them for each variable.
3013
Joe Hershberger267541f2012-12-11 22:16:34 -06003014- CONFIG_ENV_ACCESS_IGNORE_FORCE
3015 If defined, don't allow the -f switch to env set override variable
3016 access flags.
3017
wdenkc6097192002-11-03 00:24:07 +00003018The following definitions that deal with the placement and management
3019of environment data (variable area); in general, we support the
3020following configurations:
3021
Mike Frysingerc3eb3fe2011-07-08 10:44:25 +00003022- CONFIG_BUILD_ENVCRC:
3023
3024 Builds up envcrc with the target environment so that external utils
3025 may easily extract it and embed it in final U-Boot images.
3026
wdenkc6097192002-11-03 00:24:07 +00003027BE CAREFUL! The first access to the environment happens quite early
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08003028in U-Boot initialization (when we try to get the setting of for the
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02003029console baudrate). You *MUST* have mapped your NVRAM area then, or
wdenkc6097192002-11-03 00:24:07 +00003030U-Boot will hang.
3031
3032Please note that even with NVRAM we still use a copy of the
3033environment in RAM: we could work on NVRAM directly, but we want to
3034keep settings there always unmodified except somebody uses "saveenv"
3035to save the current settings.
3036
Liu Gang0a85a9e2012-03-08 00:33:20 +00003037BE CAREFUL! For some special cases, the local device can not use
3038"saveenv" command. For example, the local device will get the
Liu Gangfc54c7f2012-08-09 05:10:01 +00003039environment stored in a remote NOR flash by SRIO or PCIE link,
3040but it can not erase, write this NOR flash by SRIO or PCIE interface.
Liu Gang0a85a9e2012-03-08 00:33:20 +00003041
Guennadi Liakhovetskib74ab732009-05-18 16:07:22 +02003042- CONFIG_NAND_ENV_DST
3043
3044 Defines address in RAM to which the nand_spl code should copy the
3045 environment. If redundant environment is used, it will be copied to
3046 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE.
3047
Bruce Adlere881cb52007-11-02 13:15:42 -07003048Please note that the environment is read-only until the monitor
wdenkc6097192002-11-03 00:24:07 +00003049has been relocated to RAM and a RAM copy of the environment has been
Simon Glass00caae62017-08-03 12:22:12 -06003050created; also, when using EEPROM you will have to use env_get_f()
wdenkc6097192002-11-03 00:24:07 +00003051until then to read environment variables.
3052
wdenk85ec0bc2003-03-31 16:34:49 +00003053The environment is protected by a CRC32 checksum. Before the monitor
3054is relocated into RAM, as a result of a bad CRC you will be working
3055with the compiled-in default environment - *silently*!!! [This is
3056necessary, because the first environment variable we need is the
3057"baudrate" setting for the console - if we have a bad CRC, we don't
3058have any device yet where we could complain.]
wdenkc6097192002-11-03 00:24:07 +00003059
3060Note: once the monitor has been relocated, then it will complain if
3061the default environment is used; a new CRC is computed as soon as you
wdenk85ec0bc2003-03-31 16:34:49 +00003062use the "saveenv" command to store a valid environment.
wdenkc6097192002-11-03 00:24:07 +00003063
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003064- CONFIG_SYS_FAULT_ECHO_LINK_DOWN:
wdenk42d1f032003-10-15 23:53:47 +00003065 Echo the inverted Ethernet link state to the fault LED.
wdenkfc3e2162003-10-08 22:33:00 +00003066
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003067 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR
wdenkfc3e2162003-10-08 22:33:00 +00003068 also needs to be defined.
3069
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003070- CONFIG_SYS_FAULT_MII_ADDR:
wdenk42d1f032003-10-15 23:53:47 +00003071 MII address of the PHY to check for the Ethernet link state.
wdenkc6097192002-11-03 00:24:07 +00003072
Ron Madridf5675aa2009-02-18 14:30:44 -08003073- CONFIG_NS16550_MIN_FUNCTIONS:
3074 Define this if you desire to only have use of the NS16550_init
3075 and NS16550_putc functions for the serial driver located at
3076 drivers/serial/ns16550.c. This option is useful for saving
3077 space for already greatly restricted images, including but not
3078 limited to NAND_SPL configurations.
3079
Simon Glassb2b92f52012-11-30 13:01:18 +00003080- CONFIG_DISPLAY_BOARDINFO
3081 Display information about the board that U-Boot is running on
3082 when U-Boot starts up. The board function checkboard() is called
3083 to do this.
3084
Simon Glasse2e3e2b2012-11-30 13:01:19 +00003085- CONFIG_DISPLAY_BOARDINFO_LATE
3086 Similar to the previous option, but display this information
3087 later, once stdio is running and output goes to the LCD, if
3088 present.
3089
Sascha Silbefeb85802013-08-11 16:40:43 +02003090- CONFIG_BOARD_SIZE_LIMIT:
3091 Maximum size of the U-Boot image. When defined, the
3092 build system checks that the actual size does not
3093 exceed it.
3094
wdenkc6097192002-11-03 00:24:07 +00003095Low Level (hardware related) configuration options:
wdenkdc7c9a12003-03-26 06:55:25 +00003096---------------------------------------------------
wdenkc6097192002-11-03 00:24:07 +00003097
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003098- CONFIG_SYS_CACHELINE_SIZE:
wdenkc6097192002-11-03 00:24:07 +00003099 Cache Line Size of the CPU.
3100
Timur Tabie46fedf2011-08-04 18:03:41 -05003101- CONFIG_SYS_CCSRBAR_DEFAULT:
3102 Default (power-on reset) physical address of CCSR on Freescale
3103 PowerPC SOCs.
3104
3105- CONFIG_SYS_CCSRBAR:
3106 Virtual address of CCSR. On a 32-bit build, this is typically
3107 the same value as CONFIG_SYS_CCSRBAR_DEFAULT.
3108
Timur Tabie46fedf2011-08-04 18:03:41 -05003109- CONFIG_SYS_CCSRBAR_PHYS:
3110 Physical address of CCSR. CCSR can be relocated to a new
3111 physical address, if desired. In this case, this macro should
Wolfgang Denkc0f40852011-10-26 10:21:21 +00003112 be set to that address. Otherwise, it should be set to the
Timur Tabie46fedf2011-08-04 18:03:41 -05003113 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR
3114 is typically relocated on 36-bit builds. It is recommended
3115 that this macro be defined via the _HIGH and _LOW macros:
3116
3117 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH
3118 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW)
3119
3120- CONFIG_SYS_CCSRBAR_PHYS_HIGH:
Wolfgang Denk4cf26092011-10-07 09:58:21 +02003121 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically
3122 either 0 (32-bit build) or 0xF (36-bit build). This macro is
Timur Tabie46fedf2011-08-04 18:03:41 -05003123 used in assembly code, so it must not contain typecasts or
3124 integer size suffixes (e.g. "ULL").
3125
3126- CONFIG_SYS_CCSRBAR_PHYS_LOW:
3127 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is
3128 used in assembly code, so it must not contain typecasts or
3129 integer size suffixes (e.g. "ULL").
3130
3131- CONFIG_SYS_CCSR_DO_NOT_RELOCATE:
3132 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be
3133 forced to a value that ensures that CCSR is not relocated.
3134
wdenk7f6c2cb2002-11-10 22:06:23 +00003135- Floppy Disk Support:
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003136 CONFIG_SYS_FDC_DRIVE_NUMBER
wdenk7f6c2cb2002-11-10 22:06:23 +00003137
3138 the default drive number (default value 0)
3139
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003140 CONFIG_SYS_ISA_IO_STRIDE
wdenk7f6c2cb2002-11-10 22:06:23 +00003141
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02003142 defines the spacing between FDC chipset registers
wdenk7f6c2cb2002-11-10 22:06:23 +00003143 (default value 1)
3144
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003145 CONFIG_SYS_ISA_IO_OFFSET
wdenk7f6c2cb2002-11-10 22:06:23 +00003146
wdenk43d96162003-03-06 00:02:04 +00003147 defines the offset of register from address. It
3148 depends on which part of the data bus is connected to
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02003149 the FDC chipset. (default value 0)
wdenk7f6c2cb2002-11-10 22:06:23 +00003150
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003151 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and
3152 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their
wdenk43d96162003-03-06 00:02:04 +00003153 default value.
wdenk7f6c2cb2002-11-10 22:06:23 +00003154
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003155 if CONFIG_SYS_FDC_HW_INIT is defined, then the function
wdenk43d96162003-03-06 00:02:04 +00003156 fdc_hw_init() is called at the beginning of the FDC
3157 setup. fdc_hw_init() must be provided by the board
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08003158 source code. It is used to make hardware-dependent
wdenk43d96162003-03-06 00:02:04 +00003159 initializations.
wdenk7f6c2cb2002-11-10 22:06:23 +00003160
Macpaul Lin0abddf82011-04-11 20:45:32 +00003161- CONFIG_IDE_AHB:
3162 Most IDE controllers were designed to be connected with PCI
3163 interface. Only few of them were designed for AHB interface.
3164 When software is doing ATA command and data transfer to
3165 IDE devices through IDE-AHB controller, some additional
3166 registers accessing to these kind of IDE-AHB controller
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08003167 is required.
Macpaul Lin0abddf82011-04-11 20:45:32 +00003168
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003169- CONFIG_SYS_IMMR: Physical address of the Internal Memory.
wdenkefe2a4d2004-12-16 21:44:03 +00003170 DO NOT CHANGE unless you know exactly what you're
Christophe Leroy907208c2017-07-06 10:23:22 +02003171 doing! (11-4) [MPC8xx systems only]
wdenkc6097192002-11-03 00:24:07 +00003172
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003173- CONFIG_SYS_INIT_RAM_ADDR:
wdenkc6097192002-11-03 00:24:07 +00003174
wdenk7152b1d2003-09-05 23:19:14 +00003175 Start address of memory area that can be used for
wdenkc6097192002-11-03 00:24:07 +00003176 initial data and stack; please note that this must be
3177 writable memory that is working WITHOUT special
3178 initialization, i. e. you CANNOT use normal RAM which
3179 will become available only after programming the
3180 memory controller and running certain initialization
3181 sequences.
3182
3183 U-Boot uses the following memory types:
Christophe Leroy907208c2017-07-06 10:23:22 +02003184 - MPC8xx: IMMR (internal memory of the CPU)
wdenkc6097192002-11-03 00:24:07 +00003185
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003186- CONFIG_SYS_GBL_DATA_OFFSET:
wdenkc6097192002-11-03 00:24:07 +00003187
3188 Offset of the initial data structure in the memory
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003189 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually
3190 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial
wdenkc6097192002-11-03 00:24:07 +00003191 data is located at the end of the available space
Wolfgang Denk553f0982010-10-26 13:32:32 +02003192 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE -
Simon Glassacd51f92016-10-02 18:01:06 -06003193 GENERATED_GBL_DATA_SIZE), and the initial stack is just
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003194 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR +
3195 CONFIG_SYS_GBL_DATA_OFFSET) downward.
wdenkc6097192002-11-03 00:24:07 +00003196
3197 Note:
3198 On the MPC824X (or other systems that use the data
3199 cache for initial memory) the address chosen for
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003200 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must
wdenkc6097192002-11-03 00:24:07 +00003201 point to an otherwise UNUSED address space between
3202 the top of RAM and the start of the PCI space.
3203
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003204- CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27)
wdenkc6097192002-11-03 00:24:07 +00003205
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003206- CONFIG_SYS_OR_TIMING_SDRAM:
wdenkc6097192002-11-03 00:24:07 +00003207 SDRAM timing
3208
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003209- CONFIG_SYS_MAMR_PTA:
wdenkc6097192002-11-03 00:24:07 +00003210 periodic timer for refresh
3211
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003212- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM,
3213 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP,
3214 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM,
3215 CONFIG_SYS_BR1_PRELIM:
wdenkc6097192002-11-03 00:24:07 +00003216 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
3217
3218- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003219 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM,
3220 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM:
wdenkc6097192002-11-03 00:24:07 +00003221 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
3222
Andrew Sharp69fd2d32012-08-29 14:16:32 +00003223- CONFIG_PCI_ENUM_ONLY
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08003224 Only scan through and get the devices on the buses.
Andrew Sharp69fd2d32012-08-29 14:16:32 +00003225 Don't do any setup work, presumably because someone or
3226 something has already done it, and we don't need to do it
3227 a second time. Useful for platforms that are pre-booted
3228 by coreboot or similar.
3229
Gabor Juhos842033e2013-05-30 07:06:12 +00003230- CONFIG_PCI_INDIRECT_BRIDGE:
3231 Enable support for indirect PCI bridges.
3232
Kumar Galaa09b9b62010-12-30 12:09:53 -06003233- CONFIG_SYS_SRIO:
3234 Chip has SRIO or not
3235
3236- CONFIG_SRIO1:
3237 Board has SRIO 1 port available
3238
3239- CONFIG_SRIO2:
3240 Board has SRIO 2 port available
3241
Liu Gangc8b28152013-05-07 16:30:46 +08003242- CONFIG_SRIO_PCIE_BOOT_MASTER
3243 Board can support master function for Boot from SRIO and PCIE
3244
Kumar Galaa09b9b62010-12-30 12:09:53 -06003245- CONFIG_SYS_SRIOn_MEM_VIRT:
3246 Virtual Address of SRIO port 'n' memory region
3247
3248- CONFIG_SYS_SRIOn_MEM_PHYS:
3249 Physical Address of SRIO port 'n' memory region
3250
3251- CONFIG_SYS_SRIOn_MEM_SIZE:
3252 Size of SRIO port 'n' memory region
3253
Fabio Estevam66bd1842013-04-11 09:35:34 +00003254- CONFIG_SYS_NAND_BUSWIDTH_16BIT
3255 Defined to tell the NAND controller that the NAND chip is using
3256 a 16 bit bus.
3257 Not all NAND drivers use this symbol.
Fabio Estevama430e912013-04-11 09:35:35 +00003258 Example of drivers that use it:
Fabio Estevam66bd1842013-04-11 09:35:34 +00003259 - drivers/mtd/nand/ndfc.c
Fabio Estevama430e912013-04-11 09:35:35 +00003260 - drivers/mtd/nand/mxc_nand.c
Alex Watermaneced4622011-05-19 15:08:36 -04003261
3262- CONFIG_SYS_NDFC_EBC0_CFG
3263 Sets the EBC0_CFG register for the NDFC. If not defined
3264 a default value will be used.
3265
Ben Warrenbb99ad62006-09-07 16:50:54 -04003266- CONFIG_SPD_EEPROM
Wolfgang Denk218ca722008-03-26 10:40:12 +01003267 Get DDR timing information from an I2C EEPROM. Common
3268 with pluggable memory modules such as SODIMMs
3269
Ben Warrenbb99ad62006-09-07 16:50:54 -04003270 SPD_EEPROM_ADDRESS
3271 I2C address of the SPD EEPROM
3272
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003273- CONFIG_SYS_SPD_BUS_NUM
Wolfgang Denk218ca722008-03-26 10:40:12 +01003274 If SPD EEPROM is on an I2C bus other than the first
3275 one, specify here. Note that the value must resolve
3276 to something your driver can deal with.
Ben Warrenbb99ad62006-09-07 16:50:54 -04003277
York Sun1b3e3c42011-06-07 09:42:16 +08003278- CONFIG_SYS_DDR_RAW_TIMING
3279 Get DDR timing information from other than SPD. Common with
3280 soldered DDR chips onboard without SPD. DDR raw timing
3281 parameters are extracted from datasheet and hard-coded into
3282 header files or board specific files.
3283
York Sun6f5e1dc2011-09-16 13:21:35 -07003284- CONFIG_FSL_DDR_INTERACTIVE
3285 Enable interactive DDR debugging. See doc/README.fsl-ddr.
3286
York Sune32d59a2015-01-06 13:18:55 -08003287- CONFIG_FSL_DDR_SYNC_REFRESH
3288 Enable sync of refresh for multiple controllers.
3289
York Sun4516ff82015-03-19 09:30:28 -07003290- CONFIG_FSL_DDR_BIST
3291 Enable built-in memory test for Freescale DDR controllers.
3292
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003293- CONFIG_SYS_83XX_DDR_USES_CS0
Wolfgang Denk218ca722008-03-26 10:40:12 +01003294 Only for 83xx systems. If specified, then DDR should
3295 be configured using CS0 and CS1 instead of CS2 and CS3.
Timur Tabi2ad6b512006-10-31 18:44:42 -06003296
wdenkc26e4542004-04-18 10:13:26 +00003297- CONFIG_RMII
3298 Enable RMII mode for all FECs.
3299 Note that this is a global option, we can't
3300 have one FEC in standard MII mode and another in RMII mode.
3301
wdenk5cf91d62004-04-23 20:32:05 +00003302- CONFIG_CRC32_VERIFY
3303 Add a verify option to the crc32 command.
3304 The syntax is:
3305
3306 => crc32 -v <address> <count> <crc32>
3307
3308 Where address/count indicate a memory area
3309 and crc32 is the correct crc32 which the
3310 area should have.
3311
wdenk56523f12004-07-11 17:40:54 +00003312- CONFIG_LOOPW
3313 Add the "loopw" memory command. This only takes effect if
Simon Glass493f4202017-08-04 16:34:27 -06003314 the memory commands are activated globally (CONFIG_CMD_MEMORY).
wdenk56523f12004-07-11 17:40:54 +00003315
stroese7b466642004-12-16 18:46:55 +00003316- CONFIG_MX_CYCLIC
3317 Add the "mdc" and "mwc" memory commands. These are cyclic
3318 "md/mw" commands.
3319 Examples:
3320
wdenkefe2a4d2004-12-16 21:44:03 +00003321 => mdc.b 10 4 500
stroese7b466642004-12-16 18:46:55 +00003322 This command will print 4 bytes (10,11,12,13) each 500 ms.
3323
wdenkefe2a4d2004-12-16 21:44:03 +00003324 => mwc.l 100 12345678 10
stroese7b466642004-12-16 18:46:55 +00003325 This command will write 12345678 to address 100 all 10 ms.
3326
wdenkefe2a4d2004-12-16 21:44:03 +00003327 This only takes effect if the memory commands are activated
Simon Glass493f4202017-08-04 16:34:27 -06003328 globally (CONFIG_CMD_MEMORY).
stroese7b466642004-12-16 18:46:55 +00003329
wdenk8aa1a2d2005-04-04 12:44:11 +00003330- CONFIG_SKIP_LOWLEVEL_INIT
Rick Chen3fafced2017-12-26 13:55:59 +08003331 [ARM, NDS32, MIPS, RISC-V only] If this variable is defined, then certain
Wolfgang Denk844f07d2010-11-27 23:30:56 +01003332 low level initializations (like setting up the memory
3333 controller) are omitted and/or U-Boot does not
3334 relocate itself into RAM.
wdenk8aa1a2d2005-04-04 12:44:11 +00003335
Wolfgang Denk844f07d2010-11-27 23:30:56 +01003336 Normally this variable MUST NOT be defined. The only
3337 exception is when U-Boot is loaded (to RAM) by some
3338 other boot loader or by a debugger which performs
3339 these initializations itself.
wdenk8aa1a2d2005-04-04 12:44:11 +00003340
Simon Glassb5bd0982016-05-05 07:28:06 -06003341- CONFIG_SKIP_LOWLEVEL_INIT_ONLY
3342 [ARM926EJ-S only] This allows just the call to lowlevel_init()
yeongjun Kim90211f72016-07-20 22:56:12 +09003343 to be skipped. The normal CP15 init (such as enabling the
Simon Glassb5bd0982016-05-05 07:28:06 -06003344 instruction cache) is still performed.
3345
Aneesh V401bb302011-07-13 05:11:07 +00003346- CONFIG_SPL_BUILD
Magnus Liljadf812382009-06-13 20:50:00 +02003347 Modifies the behaviour of start.S when compiling a loader
3348 that is executed before the actual U-Boot. E.g. when
3349 compiling a NAND SPL.
wdenk400558b2005-04-02 23:52:25 +00003350
Ying Zhang3aa29de2013-08-16 15:16:15 +08003351- CONFIG_TPL_BUILD
3352 Modifies the behaviour of start.S when compiling a loader
3353 that is executed after the SPL and before the actual U-Boot.
3354 It is loaded by the SPL.
3355
Ying Zhang5df572f2013-05-20 14:07:23 +08003356- CONFIG_SYS_MPC85XX_NO_RESETVEC
3357 Only for 85xx systems. If this variable is specified, the section
3358 .resetvec is not kept and the section .bootpg is placed in the
3359 previous 4k of the .text section.
3360
Simon Glass4213fc22013-02-24 17:33:14 +00003361- CONFIG_ARCH_MAP_SYSMEM
3362 Generally U-Boot (and in particular the md command) uses
3363 effective address. It is therefore not necessary to regard
3364 U-Boot address as virtual addresses that need to be translated
3365 to physical addresses. However, sandbox requires this, since
3366 it maintains its own little RAM buffer which contains all
3367 addressable memory. This option causes some memory accesses
3368 to be mapped through map_sysmem() / unmap_sysmem().
3369
Simon Glass588a13f2013-02-14 04:18:54 +00003370- CONFIG_X86_RESET_VECTOR
3371 If defined, the x86 reset vector code is included. This is not
3372 needed when U-Boot is running from Coreboot.
Gabe Blackb16f5212012-11-27 21:08:06 +00003373
Karicheri, Muralidharan999d7d32014-04-04 13:16:50 -04003374- CONFIG_SYS_NAND_NO_SUBPAGE_WRITE
3375 Option to disable subpage write in NAND driver
3376 driver that uses this:
3377 drivers/mtd/nand/davinci_nand.c
3378
Timur Tabif2717b42011-11-22 09:21:25 -06003379Freescale QE/FMAN Firmware Support:
3380-----------------------------------
3381
3382The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the
3383loading of "firmware", which is encoded in the QE firmware binary format.
3384This firmware often needs to be loaded during U-Boot booting, so macros
3385are used to identify the storage device (NOR flash, SPI, etc) and the address
3386within that device.
3387
Zhao Qiangdcf1d772014-03-21 16:21:44 +08003388- CONFIG_SYS_FMAN_FW_ADDR
3389 The address in the storage device where the FMAN microcode is located. The
3390 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro
3391 is also specified.
3392
3393- CONFIG_SYS_QE_FW_ADDR
3394 The address in the storage device where the QE microcode is located. The
Timur Tabif2717b42011-11-22 09:21:25 -06003395 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro
3396 is also specified.
3397
3398- CONFIG_SYS_QE_FMAN_FW_LENGTH
3399 The maximum possible size of the firmware. The firmware binary format
3400 has a field that specifies the actual size of the firmware, but it
3401 might not be possible to read any part of the firmware unless some
3402 local storage is allocated to hold the entire firmware first.
3403
3404- CONFIG_SYS_QE_FMAN_FW_IN_NOR
3405 Specifies that QE/FMAN firmware is located in NOR flash, mapped as
3406 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the
3407 virtual address in NOR flash.
3408
3409- CONFIG_SYS_QE_FMAN_FW_IN_NAND
3410 Specifies that QE/FMAN firmware is located in NAND flash.
3411 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash.
3412
3413- CONFIG_SYS_QE_FMAN_FW_IN_MMC
3414 Specifies that QE/FMAN firmware is located on the primary SD/MMC
3415 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
3416
Liu Gang292dc6c2012-03-08 00:33:18 +00003417- CONFIG_SYS_QE_FMAN_FW_IN_REMOTE
3418 Specifies that QE/FMAN firmware is located in the remote (master)
3419 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which
Liu Gangfc54c7f2012-08-09 05:10:01 +00003420 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound
3421 window->master inbound window->master LAW->the ucode address in
3422 master's memory space.
Timur Tabif2717b42011-11-22 09:21:25 -06003423
J. German Riverab940ca62014-06-23 15:15:55 -07003424Freescale Layerscape Management Complex Firmware Support:
3425---------------------------------------------------------
3426The Freescale Layerscape Management Complex (MC) supports the loading of
3427"firmware".
3428This firmware often needs to be loaded during U-Boot booting, so macros
3429are used to identify the storage device (NOR flash, SPI, etc) and the address
3430within that device.
3431
3432- CONFIG_FSL_MC_ENET
3433 Enable the MC driver for Layerscape SoCs.
3434
Prabhakar Kushwaha5c055082015-06-02 10:55:52 +05303435Freescale Layerscape Debug Server Support:
3436-------------------------------------------
3437The Freescale Layerscape Debug Server Support supports the loading of
3438"Debug Server firmware" and triggering SP boot-rom.
3439This firmware often needs to be loaded during U-Boot booting.
3440
York Sunc0492142015-12-07 11:08:58 -08003441- CONFIG_SYS_MC_RSV_MEM_ALIGN
3442 Define alignment of reserved memory MC requires
Prabhakar Kushwaha5c055082015-06-02 10:55:52 +05303443
Paul Kocialkowskif3f431a2015-07-26 18:48:15 +02003444Reproducible builds
3445-------------------
3446
3447In order to achieve reproducible builds, timestamps used in the U-Boot build
3448process have to be set to a fixed value.
3449
3450This is done using the SOURCE_DATE_EPOCH environment variable.
3451SOURCE_DATE_EPOCH is to be set on the build host's shell, not as a configuration
3452option for U-Boot or an environment variable in U-Boot.
3453
3454SOURCE_DATE_EPOCH should be set to a number of seconds since the epoch, in UTC.
3455
wdenkc6097192002-11-03 00:24:07 +00003456Building the Software:
3457======================
3458
Wolfgang Denk218ca722008-03-26 10:40:12 +01003459Building U-Boot has been tested in several native build environments
3460and in many different cross environments. Of course we cannot support
3461all possibly existing versions of cross development tools in all
3462(potentially obsolete) versions. In case of tool chain problems we
3463recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK)
3464which is extensively used to build and test U-Boot.
wdenkc6097192002-11-03 00:24:07 +00003465
Wolfgang Denk218ca722008-03-26 10:40:12 +01003466If you are not using a native environment, it is assumed that you
3467have GNU cross compiling tools available in your path. In this case,
3468you must set the environment variable CROSS_COMPILE in your shell.
3469Note that no changes to the Makefile or any other source files are
3470necessary. For example using the ELDK on a 4xx CPU, please enter:
wdenkc6097192002-11-03 00:24:07 +00003471
Wolfgang Denk218ca722008-03-26 10:40:12 +01003472 $ CROSS_COMPILE=ppc_4xx-
3473 $ export CROSS_COMPILE
wdenkc6097192002-11-03 00:24:07 +00003474
Peter Tyser2f8d3962009-03-13 18:54:51 -05003475Note: If you wish to generate Windows versions of the utilities in
3476 the tools directory you can use the MinGW toolchain
3477 (http://www.mingw.org). Set your HOST tools to the MinGW
3478 toolchain and execute 'make tools'. For example:
3479
3480 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools
3481
3482 Binaries such as tools/mkimage.exe will be created which can
3483 be executed on computers running Windows.
3484
Wolfgang Denk218ca722008-03-26 10:40:12 +01003485U-Boot is intended to be simple to build. After installing the
3486sources you must configure U-Boot for one specific board type. This
wdenkc6097192002-11-03 00:24:07 +00003487is done by typing:
3488
Holger Freytherab584d62014-08-04 09:26:05 +02003489 make NAME_defconfig
wdenkc6097192002-11-03 00:24:07 +00003490
Holger Freytherab584d62014-08-04 09:26:05 +02003491where "NAME_defconfig" is the name of one of the existing configu-
Michael Jones4d675ae2012-03-15 22:48:10 +00003492rations; see boards.cfg for supported names.
wdenk54387ac2003-10-08 22:45:44 +00003493
wdenk2729af92004-05-03 20:45:30 +00003494Note: for some board special configuration names may exist; check if
3495 additional information is available from the board vendor; for
3496 instance, the TQM823L systems are available without (standard)
3497 or with LCD support. You can select such additional "features"
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02003498 when choosing the configuration, i. e.
wdenkc6097192002-11-03 00:24:07 +00003499
Holger Freytherab584d62014-08-04 09:26:05 +02003500 make TQM823L_defconfig
wdenk2729af92004-05-03 20:45:30 +00003501 - will configure for a plain TQM823L, i. e. no LCD support
wdenkc6097192002-11-03 00:24:07 +00003502
Holger Freytherab584d62014-08-04 09:26:05 +02003503 make TQM823L_LCD_defconfig
wdenk2729af92004-05-03 20:45:30 +00003504 - will configure for a TQM823L with U-Boot console on LCD
wdenkc6097192002-11-03 00:24:07 +00003505
wdenk2729af92004-05-03 20:45:30 +00003506 etc.
wdenkc6097192002-11-03 00:24:07 +00003507
wdenkc6097192002-11-03 00:24:07 +00003508
wdenk2729af92004-05-03 20:45:30 +00003509Finally, type "make all", and you should get some working U-Boot
3510images ready for download to / installation on your system:
wdenkc6097192002-11-03 00:24:07 +00003511
wdenk2729af92004-05-03 20:45:30 +00003512- "u-boot.bin" is a raw binary image
3513- "u-boot" is an image in ELF binary format
3514- "u-boot.srec" is in Motorola S-Record format
wdenkc6097192002-11-03 00:24:07 +00003515
Marian Balakowiczbaf31242006-09-07 17:25:40 +02003516By default the build is performed locally and the objects are saved
3517in the source directory. One of the two methods can be used to change
3518this behavior and build U-Boot to some external directory:
3519
35201. Add O= to the make command line invocations:
3521
3522 make O=/tmp/build distclean
Holger Freytherab584d62014-08-04 09:26:05 +02003523 make O=/tmp/build NAME_defconfig
Marian Balakowiczbaf31242006-09-07 17:25:40 +02003524 make O=/tmp/build all
3525
Timo Ketolaadbba992014-11-06 14:39:05 +020035262. Set environment variable KBUILD_OUTPUT to point to the desired location:
Marian Balakowiczbaf31242006-09-07 17:25:40 +02003527
Timo Ketolaadbba992014-11-06 14:39:05 +02003528 export KBUILD_OUTPUT=/tmp/build
Marian Balakowiczbaf31242006-09-07 17:25:40 +02003529 make distclean
Holger Freytherab584d62014-08-04 09:26:05 +02003530 make NAME_defconfig
Marian Balakowiczbaf31242006-09-07 17:25:40 +02003531 make all
3532
Timo Ketolaadbba992014-11-06 14:39:05 +02003533Note that the command line "O=" setting overrides the KBUILD_OUTPUT environment
Marian Balakowiczbaf31242006-09-07 17:25:40 +02003534variable.
3535
Daniel Schwierzeck215bb1c2018-01-26 16:31:04 +01003536User specific CPPFLAGS, AFLAGS and CFLAGS can be passed to the compiler by
3537setting the according environment variables KCPPFLAGS, KAFLAGS and KCFLAGS.
3538For example to treat all compiler warnings as errors:
3539
3540 make KCFLAGS=-Werror
wdenkc6097192002-11-03 00:24:07 +00003541
wdenk2729af92004-05-03 20:45:30 +00003542Please be aware that the Makefiles assume you are using GNU make, so
3543for instance on NetBSD you might need to use "gmake" instead of
3544native "make".
wdenkc6097192002-11-03 00:24:07 +00003545
wdenkc6097192002-11-03 00:24:07 +00003546
wdenk2729af92004-05-03 20:45:30 +00003547If the system board that you have is not listed, then you will need
3548to port U-Boot to your hardware platform. To do this, follow these
3549steps:
wdenkc6097192002-11-03 00:24:07 +00003550
Phil Sutter3c1496c2015-12-25 14:41:18 +010035511. Create a new directory to hold your board specific code. Add any
wdenk2729af92004-05-03 20:45:30 +00003552 files you need. In your board directory, you will need at least
Phil Sutter3c1496c2015-12-25 14:41:18 +01003553 the "Makefile" and a "<board>.c".
35542. Create a new configuration file "include/configs/<board>.h" for
3555 your board.
wdenk2729af92004-05-03 20:45:30 +000035563. If you're porting U-Boot to a new CPU, then also create a new
3557 directory to hold your CPU specific code. Add any files you need.
Holger Freytherab584d62014-08-04 09:26:05 +020035584. Run "make <board>_defconfig" with your new name.
wdenk2729af92004-05-03 20:45:30 +000035595. Type "make", and you should get a working "u-boot.srec" file
3560 to be installed on your target system.
35616. Debug and solve any problems that might arise.
3562 [Of course, this last step is much harder than it sounds.]
wdenkc6097192002-11-03 00:24:07 +00003563
wdenkc6097192002-11-03 00:24:07 +00003564
wdenk2729af92004-05-03 20:45:30 +00003565Testing of U-Boot Modifications, Ports to New Hardware, etc.:
3566==============================================================
wdenkc6097192002-11-03 00:24:07 +00003567
Wolfgang Denk218ca722008-03-26 10:40:12 +01003568If you have modified U-Boot sources (for instance added a new board
3569or support for new devices, a new CPU, etc.) you are expected to
wdenk2729af92004-05-03 20:45:30 +00003570provide feedback to the other developers. The feedback normally takes
3571the form of a "patch", i. e. a context diff against a certain (latest
Wolfgang Denk218ca722008-03-26 10:40:12 +01003572official or latest in the git repository) version of U-Boot sources.
wdenkc6097192002-11-03 00:24:07 +00003573
Wolfgang Denk218ca722008-03-26 10:40:12 +01003574But before you submit such a patch, please verify that your modifi-
3575cation did not break existing code. At least make sure that *ALL* of
wdenk2729af92004-05-03 20:45:30 +00003576the supported boards compile WITHOUT ANY compiler warnings. To do so,
Simon Glass6de80f22016-07-27 20:33:08 -06003577just run the buildman script (tools/buildman/buildman), which will
3578configure and build U-Boot for ALL supported system. Be warned, this
3579will take a while. Please see the buildman README, or run 'buildman -H'
3580for documentation.
Marian Balakowiczbaf31242006-09-07 17:25:40 +02003581
3582
wdenk2729af92004-05-03 20:45:30 +00003583See also "U-Boot Porting Guide" below.
wdenkc6097192002-11-03 00:24:07 +00003584
wdenkc6097192002-11-03 00:24:07 +00003585
wdenk2729af92004-05-03 20:45:30 +00003586Monitor Commands - Overview:
3587============================
wdenkc6097192002-11-03 00:24:07 +00003588
wdenk2729af92004-05-03 20:45:30 +00003589go - start application at address 'addr'
3590run - run commands in an environment variable
3591bootm - boot application image from memory
3592bootp - boot image via network using BootP/TFTP protocol
Marek Vasut44f074c2012-03-14 21:52:45 +00003593bootz - boot zImage from memory
wdenk2729af92004-05-03 20:45:30 +00003594tftpboot- boot image via network using TFTP protocol
3595 and env variables "ipaddr" and "serverip"
3596 (and eventually "gatewayip")
Simon Glass1fb7cd42011-10-24 18:00:07 +00003597tftpput - upload a file via network using TFTP protocol
wdenk2729af92004-05-03 20:45:30 +00003598rarpboot- boot image via network using RARP/TFTP protocol
3599diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
3600loads - load S-Record file over serial line
3601loadb - load binary file over serial line (kermit mode)
3602md - memory display
3603mm - memory modify (auto-incrementing)
3604nm - memory modify (constant address)
3605mw - memory write (fill)
3606cp - memory copy
3607cmp - memory compare
3608crc32 - checksum calculation
Peter Tyser0f89c542009-04-18 22:34:03 -05003609i2c - I2C sub-system
wdenk2729af92004-05-03 20:45:30 +00003610sspi - SPI utility commands
3611base - print or set address offset
3612printenv- print environment variables
3613setenv - set environment variables
3614saveenv - save environment variables to persistent storage
3615protect - enable or disable FLASH write protection
3616erase - erase FLASH memory
3617flinfo - print FLASH memory information
Karl O. Pinc10635af2012-08-03 05:57:21 +00003618nand - NAND memory operations (see doc/README.nand)
wdenk2729af92004-05-03 20:45:30 +00003619bdinfo - print Board Info structure
3620iminfo - print header information for application image
3621coninfo - print console devices and informations
3622ide - IDE sub-system
3623loop - infinite loop on address range
wdenk56523f12004-07-11 17:40:54 +00003624loopw - infinite write loop on address range
wdenk2729af92004-05-03 20:45:30 +00003625mtest - simple RAM test
3626icache - enable or disable instruction cache
3627dcache - enable or disable data cache
3628reset - Perform RESET of the CPU
3629echo - echo args to console
3630version - print monitor version
3631help - print online help
3632? - alias for 'help'
wdenkc6097192002-11-03 00:24:07 +00003633
wdenkc6097192002-11-03 00:24:07 +00003634
wdenk2729af92004-05-03 20:45:30 +00003635Monitor Commands - Detailed Description:
3636========================================
wdenkc6097192002-11-03 00:24:07 +00003637
wdenk2729af92004-05-03 20:45:30 +00003638TODO.
wdenkc6097192002-11-03 00:24:07 +00003639
wdenk2729af92004-05-03 20:45:30 +00003640For now: just type "help <command>".
wdenkc6097192002-11-03 00:24:07 +00003641
3642
wdenk2729af92004-05-03 20:45:30 +00003643Environment Variables:
3644======================
wdenkc6097192002-11-03 00:24:07 +00003645
wdenk2729af92004-05-03 20:45:30 +00003646U-Boot supports user configuration using Environment Variables which
3647can be made persistent by saving to Flash memory.
wdenkc6097192002-11-03 00:24:07 +00003648
wdenk2729af92004-05-03 20:45:30 +00003649Environment Variables are set using "setenv", printed using
3650"printenv", and saved to Flash using "saveenv". Using "setenv"
3651without a value can be used to delete a variable from the
3652environment. As long as you don't save the environment you are
3653working with an in-memory copy. In case the Flash area containing the
3654environment is erased by accident, a default environment is provided.
wdenkc6097192002-11-03 00:24:07 +00003655
Wolfgang Denkc96f86e2010-01-17 23:55:53 +01003656Some configuration options can be set using Environment Variables.
3657
3658List of environment variables (most likely not complete):
wdenkc6097192002-11-03 00:24:07 +00003659
wdenk2729af92004-05-03 20:45:30 +00003660 baudrate - see CONFIG_BAUDRATE
wdenkc6097192002-11-03 00:24:07 +00003661
wdenk2729af92004-05-03 20:45:30 +00003662 bootdelay - see CONFIG_BOOTDELAY
wdenkc6097192002-11-03 00:24:07 +00003663
wdenk2729af92004-05-03 20:45:30 +00003664 bootcmd - see CONFIG_BOOTCOMMAND
wdenkc6097192002-11-03 00:24:07 +00003665
wdenk2729af92004-05-03 20:45:30 +00003666 bootargs - Boot arguments when booting an RTOS image
wdenkc6097192002-11-03 00:24:07 +00003667
wdenk2729af92004-05-03 20:45:30 +00003668 bootfile - Name of the image to load with TFTP
wdenkc6097192002-11-03 00:24:07 +00003669
Bartlomiej Sieka7d721e32008-04-14 15:44:16 +02003670 bootm_low - Memory range available for image processing in the bootm
3671 command can be restricted. This variable is given as
3672 a hexadecimal number and defines lowest address allowed
3673 for use by the bootm command. See also "bootm_size"
3674 environment variable. Address defined by "bootm_low" is
3675 also the base of the initial memory mapping for the Linux
Grant Likelyc3624e62011-03-28 09:58:43 +00003676 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and
3677 bootm_mapsize.
3678
Wolfgang Denkc0f40852011-10-26 10:21:21 +00003679 bootm_mapsize - Size of the initial memory mapping for the Linux kernel.
Grant Likelyc3624e62011-03-28 09:58:43 +00003680 This variable is given as a hexadecimal number and it
3681 defines the size of the memory region starting at base
3682 address bootm_low that is accessible by the Linux kernel
3683 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used
3684 as the default value if it is defined, and bootm_size is
3685 used otherwise.
Bartlomiej Sieka7d721e32008-04-14 15:44:16 +02003686
3687 bootm_size - Memory range available for image processing in the bootm
3688 command can be restricted. This variable is given as
3689 a hexadecimal number and defines the size of the region
3690 allowed for use by the bootm command. See also "bootm_low"
3691 environment variable.
3692
Bartlomiej Sieka4bae9092008-10-01 15:26:31 +02003693 updatefile - Location of the software update file on a TFTP server, used
3694 by the automatic software update feature. Please refer to
3695 documentation in doc/README.update for more details.
3696
wdenk2729af92004-05-03 20:45:30 +00003697 autoload - if set to "no" (any string beginning with 'n'),
3698 "bootp" will just load perform a lookup of the
3699 configuration from the BOOTP server, but not try to
3700 load any image using TFTP
wdenkc6097192002-11-03 00:24:07 +00003701
wdenk2729af92004-05-03 20:45:30 +00003702 autostart - if set to "yes", an image loaded using the "bootp",
3703 "rarpboot", "tftpboot" or "diskboot" commands will
3704 be automatically started (by internally calling
3705 "bootm")
wdenkc6097192002-11-03 00:24:07 +00003706
wdenk2729af92004-05-03 20:45:30 +00003707 If set to "no", a standalone image passed to the
3708 "bootm" command will be copied to the load address
3709 (and eventually uncompressed), but NOT be started.
3710 This can be used to load and uncompress arbitrary
3711 data.
wdenkc6097192002-11-03 00:24:07 +00003712
David A. Longa28afca2011-07-09 16:40:19 -04003713 fdt_high - if set this restricts the maximum address that the
3714 flattened device tree will be copied into upon boot.
Shawn Guofa34f6b2012-01-09 21:54:08 +00003715 For example, if you have a system with 1 GB memory
3716 at physical address 0x10000000, while Linux kernel
3717 only recognizes the first 704 MB as low memory, you
3718 may need to set fdt_high as 0x3C000000 to have the
3719 device tree blob be copied to the maximum address
3720 of the 704 MB low memory, so that Linux kernel can
3721 access it during the boot procedure.
3722
David A. Longa28afca2011-07-09 16:40:19 -04003723 If this is set to the special value 0xFFFFFFFF then
3724 the fdt will not be copied at all on boot. For this
3725 to work it must reside in writable memory, have
3726 sufficient padding on the end of it for u-boot to
3727 add the information it needs into it, and the memory
3728 must be accessible by the kernel.
3729
Simon Glasseea63e02011-10-24 19:15:34 +00003730 fdtcontroladdr- if set this is the address of the control flattened
3731 device tree used by U-Boot when CONFIG_OF_CONTROL is
3732 defined.
3733
wdenk17ea1172004-06-06 21:51:03 +00003734 i2cfast - (PPC405GP|PPC405EP only)
3735 if set to 'y' configures Linux I2C driver for fast
3736 mode (400kHZ). This environment variable is used in
3737 initialization code. So, for changes to be effective
3738 it must be saved and board must be reset.
3739
wdenk2729af92004-05-03 20:45:30 +00003740 initrd_high - restrict positioning of initrd images:
3741 If this variable is not set, initrd images will be
3742 copied to the highest possible address in RAM; this
3743 is usually what you want since it allows for
3744 maximum initrd size. If for some reason you want to
3745 make sure that the initrd image is loaded below the
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003746 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment
wdenk2729af92004-05-03 20:45:30 +00003747 variable to a value of "no" or "off" or "0".
3748 Alternatively, you can set it to a maximum upper
3749 address to use (U-Boot will still check that it
3750 does not overwrite the U-Boot stack and data).
wdenkc6097192002-11-03 00:24:07 +00003751
wdenk2729af92004-05-03 20:45:30 +00003752 For instance, when you have a system with 16 MB
3753 RAM, and want to reserve 4 MB from use by Linux,
3754 you can do this by adding "mem=12M" to the value of
3755 the "bootargs" variable. However, now you must make
3756 sure that the initrd image is placed in the first
3757 12 MB as well - this can be done with
wdenkc6097192002-11-03 00:24:07 +00003758
wdenk2729af92004-05-03 20:45:30 +00003759 setenv initrd_high 00c00000
wdenkc6097192002-11-03 00:24:07 +00003760
wdenk2729af92004-05-03 20:45:30 +00003761 If you set initrd_high to 0xFFFFFFFF, this is an
3762 indication to U-Boot that all addresses are legal
3763 for the Linux kernel, including addresses in flash
3764 memory. In this case U-Boot will NOT COPY the
3765 ramdisk at all. This may be useful to reduce the
3766 boot time on your system, but requires that this
3767 feature is supported by your Linux kernel.
wdenk4a6fd342003-04-12 23:38:12 +00003768
wdenk2729af92004-05-03 20:45:30 +00003769 ipaddr - IP address; needed for tftpboot command
wdenkc6097192002-11-03 00:24:07 +00003770
wdenk2729af92004-05-03 20:45:30 +00003771 loadaddr - Default load address for commands like "bootp",
3772 "rarpboot", "tftpboot", "loadb" or "diskboot"
wdenkc6097192002-11-03 00:24:07 +00003773
wdenk2729af92004-05-03 20:45:30 +00003774 loads_echo - see CONFIG_LOADS_ECHO
wdenkc6097192002-11-03 00:24:07 +00003775
wdenk2729af92004-05-03 20:45:30 +00003776 serverip - TFTP server IP address; needed for tftpboot command
wdenk38b99262003-05-23 23:18:21 +00003777
wdenk2729af92004-05-03 20:45:30 +00003778 bootretry - see CONFIG_BOOT_RETRY_TIME
wdenkc6097192002-11-03 00:24:07 +00003779
wdenk2729af92004-05-03 20:45:30 +00003780 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
wdenkc6097192002-11-03 00:24:07 +00003781
wdenk2729af92004-05-03 20:45:30 +00003782 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
wdenkc6097192002-11-03 00:24:07 +00003783
Mike Frysingere2a53452011-10-02 10:01:27 +00003784 ethprime - controls which interface is used first.
wdenkc6097192002-11-03 00:24:07 +00003785
Mike Frysingere2a53452011-10-02 10:01:27 +00003786 ethact - controls which interface is currently active.
3787 For example you can do the following
wdenkc6097192002-11-03 00:24:07 +00003788
Heiko Schocher48690d82010-07-20 17:45:02 +02003789 => setenv ethact FEC
3790 => ping 192.168.0.1 # traffic sent on FEC
3791 => setenv ethact SCC
3792 => ping 10.0.0.1 # traffic sent on SCC
wdenkc6097192002-11-03 00:24:07 +00003793
Matthias Fuchse1692572008-01-17 07:45:05 +01003794 ethrotate - When set to "no" U-Boot does not go through all
3795 available network interfaces.
3796 It just stays at the currently selected interface.
3797
Wolfgang Denkc96f86e2010-01-17 23:55:53 +01003798 netretry - When set to "no" each network operation will
wdenk2729af92004-05-03 20:45:30 +00003799 either succeed or fail without retrying.
3800 When set to "once" the network operation will
3801 fail when all the available network interfaces
3802 are tried once without success.
3803 Useful on scripts which control the retry operation
3804 themselves.
wdenkc6097192002-11-03 00:24:07 +00003805
Jean-Christophe PLAGNIOL-VILLARDb4e2f892009-01-31 09:53:39 +01003806 npe_ucode - set load address for the NPE microcode
Jean-Christophe PLAGNIOL-VILLARDa1cf0272008-01-07 08:41:34 +01003807
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08003808 silent_linux - If set then Linux will be told to boot silently, by
Simon Glass8d51aac2013-07-16 20:10:00 -07003809 changing the console to be empty. If "yes" it will be
3810 made silent. If "no" it will not be made silent. If
3811 unset, then it will be made silent if the U-Boot console
3812 is silent.
3813
Albert ARIBAUD \(3ADEV\)f5fb7342015-10-12 00:02:57 +02003814 tftpsrcp - If this is set, the value is used for TFTP's
Wolfgang Denkecb0ccd2005-09-24 22:37:32 +02003815 UDP source port.
3816
Albert ARIBAUD \(3ADEV\)f5fb7342015-10-12 00:02:57 +02003817 tftpdstp - If this is set, the value is used for TFTP's UDP
Wolfgang Denk28cb9372005-09-24 23:25:46 +02003818 destination port instead of the Well Know Port 69.
3819
Wolfgang Denkc96f86e2010-01-17 23:55:53 +01003820 tftpblocksize - Block size to use for TFTP transfers; if not set,
3821 we use the TFTP server's default block size
3822
3823 tftptimeout - Retransmission timeout for TFTP packets (in milli-
3824 seconds, minimum value is 1000 = 1 second). Defines
3825 when a packet is considered to be lost so it has to
3826 be retransmitted. The default is 5000 = 5 seconds.
3827 Lowering this value may make downloads succeed
3828 faster in networks with high packet loss rates or
3829 with unreliable TFTP servers.
3830
Albert ARIBAUD \(3ADEV\)f5fb7342015-10-12 00:02:57 +02003831 tftptimeoutcountmax - maximum count of TFTP timeouts (no
3832 unit, minimum value = 0). Defines how many timeouts
3833 can happen during a single file transfer before that
3834 transfer is aborted. The default is 10, and 0 means
3835 'no timeouts allowed'. Increasing this value may help
3836 downloads succeed with high packet loss rates, or with
3837 unreliable TFTP servers or client hardware.
3838
Wolfgang Denkc96f86e2010-01-17 23:55:53 +01003839 vlan - When set to a value < 4095 the traffic over
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02003840 Ethernet is encapsulated/received over 802.1q
wdenk2729af92004-05-03 20:45:30 +00003841 VLAN tagged frames.
wdenka3d991b2004-04-15 21:48:45 +00003842
Alexandre Messier50768f52016-02-01 17:08:57 -05003843 bootpretryperiod - Period during which BOOTP/DHCP sends retries.
3844 Unsigned value, in milliseconds. If not set, the period will
3845 be either the default (28000), or a value based on
3846 CONFIG_NET_RETRY_COUNT, if defined. This value has
3847 precedence over the valu based on CONFIG_NET_RETRY_COUNT.
3848
Jason Hobbsdc0b7b02011-08-31 05:37:28 +00003849The following image location variables contain the location of images
3850used in booting. The "Image" column gives the role of the image and is
3851not an environment variable name. The other columns are environment
3852variable names. "File Name" gives the name of the file on a TFTP
3853server, "RAM Address" gives the location in RAM the image will be
3854loaded to, and "Flash Location" gives the image's address in NOR
3855flash or offset in NAND flash.
3856
3857*Note* - these variables don't have to be defined for all boards, some
Fabio Estevamaed9fed2015-04-25 18:53:10 -03003858boards currently use other variables for these purposes, and some
Jason Hobbsdc0b7b02011-08-31 05:37:28 +00003859boards use these variables for other purposes.
3860
Wolfgang Denkc0f40852011-10-26 10:21:21 +00003861Image File Name RAM Address Flash Location
3862----- --------- ----------- --------------
3863u-boot u-boot u-boot_addr_r u-boot_addr
3864Linux kernel bootfile kernel_addr_r kernel_addr
3865device tree blob fdtfile fdt_addr_r fdt_addr
3866ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr
Jason Hobbsdc0b7b02011-08-31 05:37:28 +00003867
wdenk2729af92004-05-03 20:45:30 +00003868The following environment variables may be used and automatically
3869updated by the network boot commands ("bootp" and "rarpboot"),
3870depending the information provided by your boot server:
wdenka3d991b2004-04-15 21:48:45 +00003871
wdenk2729af92004-05-03 20:45:30 +00003872 bootfile - see above
3873 dnsip - IP address of your Domain Name Server
3874 dnsip2 - IP address of your secondary Domain Name Server
3875 gatewayip - IP address of the Gateway (Router) to use
3876 hostname - Target hostname
3877 ipaddr - see above
3878 netmask - Subnet Mask
3879 rootpath - Pathname of the root filesystem on the NFS server
3880 serverip - see above
wdenka3d991b2004-04-15 21:48:45 +00003881
wdenka3d991b2004-04-15 21:48:45 +00003882
wdenk2729af92004-05-03 20:45:30 +00003883There are two special Environment Variables:
wdenkc6097192002-11-03 00:24:07 +00003884
wdenk2729af92004-05-03 20:45:30 +00003885 serial# - contains hardware identification information such
3886 as type string and/or serial number
3887 ethaddr - Ethernet address
wdenkc6097192002-11-03 00:24:07 +00003888
wdenk2729af92004-05-03 20:45:30 +00003889These variables can be set only once (usually during manufacturing of
3890the board). U-Boot refuses to delete or overwrite these variables
3891once they have been set once.
wdenkc6097192002-11-03 00:24:07 +00003892
3893
wdenk2729af92004-05-03 20:45:30 +00003894Further special Environment Variables:
wdenkc6097192002-11-03 00:24:07 +00003895
wdenk2729af92004-05-03 20:45:30 +00003896 ver - Contains the U-Boot version string as printed
3897 with the "version" command. This variable is
3898 readonly (see CONFIG_VERSION_VARIABLE).
wdenkc6097192002-11-03 00:24:07 +00003899
wdenkc6097192002-11-03 00:24:07 +00003900
wdenk2729af92004-05-03 20:45:30 +00003901Please note that changes to some configuration parameters may take
3902only effect after the next boot (yes, that's just like Windoze :-).
wdenkc6097192002-11-03 00:24:07 +00003903
stroesec1551ea2003-04-04 15:53:41 +00003904
Joe Hershberger170ab112012-12-11 22:16:24 -06003905Callback functions for environment variables:
3906---------------------------------------------
3907
3908For some environment variables, the behavior of u-boot needs to change
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08003909when their values are changed. This functionality allows functions to
Joe Hershberger170ab112012-12-11 22:16:24 -06003910be associated with arbitrary variables. On creation, overwrite, or
3911deletion, the callback will provide the opportunity for some side
3912effect to happen or for the change to be rejected.
3913
3914The callbacks are named and associated with a function using the
3915U_BOOT_ENV_CALLBACK macro in your board or driver code.
3916
3917These callbacks are associated with variables in one of two ways. The
3918static list can be added to by defining CONFIG_ENV_CALLBACK_LIST_STATIC
3919in the board configuration to a string that defines a list of
3920associations. The list must be in the following format:
3921
3922 entry = variable_name[:callback_name]
3923 list = entry[,list]
3924
3925If the callback name is not specified, then the callback is deleted.
3926Spaces are also allowed anywhere in the list.
3927
3928Callbacks can also be associated by defining the ".callbacks" variable
3929with the same list format above. Any association in ".callbacks" will
3930override any association in the static list. You can define
3931CONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08003932".callbacks" environment variable in the default or embedded environment.
Joe Hershberger170ab112012-12-11 22:16:24 -06003933
Joe Hershbergerbdf1fe42015-05-20 14:27:20 -05003934If CONFIG_REGEX is defined, the variable_name above is evaluated as a
3935regular expression. This allows multiple variables to be connected to
3936the same callback without explicitly listing them all out.
3937
Heinrich Schuchardt1b040472018-07-29 11:08:14 +02003938The signature of the callback functions is:
3939
3940 int callback(const char *name, const char *value, enum env_op op, int flags)
3941
3942* name - changed environment variable
3943* value - new value of the environment variable
3944* op - operation (create, overwrite, or delete)
3945* flags - attributes of the environment variable change, see flags H_* in
3946 include/search.h
3947
3948The return value is 0 if the variable change is accepted and 1 otherwise.
Joe Hershberger170ab112012-12-11 22:16:24 -06003949
wdenk2729af92004-05-03 20:45:30 +00003950Command Line Parsing:
3951=====================
stroesec1551ea2003-04-04 15:53:41 +00003952
wdenk2729af92004-05-03 20:45:30 +00003953There are two different command line parsers available with U-Boot:
3954the old "simple" one, and the much more powerful "hush" shell:
stroesec1551ea2003-04-04 15:53:41 +00003955
wdenk2729af92004-05-03 20:45:30 +00003956Old, simple command line parser:
3957--------------------------------
wdenkc6097192002-11-03 00:24:07 +00003958
wdenk2729af92004-05-03 20:45:30 +00003959- supports environment variables (through setenv / saveenv commands)
3960- several commands on one line, separated by ';'
Wolfgang Denkfe126d82005-11-20 21:40:11 +01003961- variable substitution using "... ${name} ..." syntax
wdenk2729af92004-05-03 20:45:30 +00003962- special characters ('$', ';') can be escaped by prefixing with '\',
3963 for example:
Wolfgang Denkfe126d82005-11-20 21:40:11 +01003964 setenv bootcmd bootm \${address}
wdenk2729af92004-05-03 20:45:30 +00003965- You can also escape text by enclosing in single apostrophes, for example:
3966 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
wdenkc6097192002-11-03 00:24:07 +00003967
wdenk2729af92004-05-03 20:45:30 +00003968Hush shell:
3969-----------
wdenkf07771c2003-05-28 08:06:31 +00003970
wdenk2729af92004-05-03 20:45:30 +00003971- similar to Bourne shell, with control structures like
3972 if...then...else...fi, for...do...done; while...do...done,
3973 until...do...done, ...
3974- supports environment ("global") variables (through setenv / saveenv
3975 commands) and local shell variables (through standard shell syntax
3976 "name=value"); only environment variables can be used with "run"
3977 command
wdenkf07771c2003-05-28 08:06:31 +00003978
wdenk2729af92004-05-03 20:45:30 +00003979General rules:
3980--------------
wdenkf07771c2003-05-28 08:06:31 +00003981
wdenk2729af92004-05-03 20:45:30 +00003982(1) If a command line (or an environment variable executed by a "run"
3983 command) contains several commands separated by semicolon, and
3984 one of these commands fails, then the remaining commands will be
3985 executed anyway.
wdenkf07771c2003-05-28 08:06:31 +00003986
wdenk2729af92004-05-03 20:45:30 +00003987(2) If you execute several variables with one call to run (i. e.
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02003988 calling run with a list of variables as arguments), any failing
wdenk2729af92004-05-03 20:45:30 +00003989 command will cause "run" to terminate, i. e. the remaining
3990 variables are not executed.
wdenkf07771c2003-05-28 08:06:31 +00003991
wdenk2729af92004-05-03 20:45:30 +00003992Note for Redundant Ethernet Interfaces:
3993=======================================
wdenkf07771c2003-05-28 08:06:31 +00003994
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02003995Some boards come with redundant Ethernet interfaces; U-Boot supports
wdenk2729af92004-05-03 20:45:30 +00003996such configurations and is capable of automatic selection of a
3997"working" interface when needed. MAC assignment works as follows:
wdenkf07771c2003-05-28 08:06:31 +00003998
wdenk2729af92004-05-03 20:45:30 +00003999Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
4000MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
4001"eth1addr" (=>eth1), "eth2addr", ...
wdenkf07771c2003-05-28 08:06:31 +00004002
wdenk2729af92004-05-03 20:45:30 +00004003If the network interface stores some valid MAC address (for instance
4004in SROM), this is used as default address if there is NO correspon-
4005ding setting in the environment; if the corresponding environment
4006variable is set, this overrides the settings in the card; that means:
wdenkf07771c2003-05-28 08:06:31 +00004007
wdenk2729af92004-05-03 20:45:30 +00004008o If the SROM has a valid MAC address, and there is no address in the
4009 environment, the SROM's address is used.
wdenkc6097192002-11-03 00:24:07 +00004010
wdenk2729af92004-05-03 20:45:30 +00004011o If there is no valid address in the SROM, and a definition in the
4012 environment exists, then the value from the environment variable is
4013 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
4016 both addresses are the same, this MAC address is used.
wdenkc6097192002-11-03 00:24:07 +00004017
wdenk2729af92004-05-03 20:45:30 +00004018o If both the SROM and the environment contain a MAC address, and the
4019 addresses differ, the value from the environment is used and a
4020 warning is printed.
wdenkc6097192002-11-03 00:24:07 +00004021
wdenk2729af92004-05-03 20:45:30 +00004022o If neither SROM nor the environment contain a MAC address, an error
Joe Hershbergerbef10142015-05-04 14:55:13 -05004023 is raised. If CONFIG_NET_RANDOM_ETHADDR is defined, then in this case
4024 a random, locally-assigned MAC is used.
wdenkc6097192002-11-03 00:24:07 +00004025
Ben Warrenecee9322010-04-26 11:11:46 -07004026If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses
Wolfgang Denkc0f40852011-10-26 10:21:21 +00004027will be programmed into hardware as part of the initialization process. This
Ben Warrenecee9322010-04-26 11:11:46 -07004028may be skipped by setting the appropriate 'ethmacskip' environment variable.
4029The naming convention is as follows:
4030"ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc.
wdenkc6097192002-11-03 00:24:07 +00004031
wdenk2729af92004-05-03 20:45:30 +00004032Image Formats:
4033==============
wdenkc6097192002-11-03 00:24:07 +00004034
Marian Balakowicz3310c542008-03-12 12:13:13 +01004035U-Boot is capable of booting (and performing other auxiliary operations on)
4036images in two formats:
4037
4038New uImage format (FIT)
4039-----------------------
4040
4041Flexible and powerful format based on Flattened Image Tree -- FIT (similar
4042to Flattened Device Tree). It allows the use of images with multiple
4043components (several kernels, ramdisks, etc.), with contents protected by
4044SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
4045
4046
4047Old uImage format
4048-----------------
4049
4050Old image format is based on binary files which can be basically anything,
4051preceded by a special header; see the definitions in include/image.h for
4052details; basically, the header defines the following image properties:
wdenkc6097192002-11-03 00:24:07 +00004053
wdenk2729af92004-05-03 20:45:30 +00004054* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
4055 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
Peter Tyserf5ed9e32008-09-08 14:56:49 -05004056 LynxOS, pSOS, QNX, RTEMS, INTEGRITY;
4057 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS,
4058 INTEGRITY).
Andy Shevchenkodaab59a2017-07-05 16:25:22 +03004059* Target CPU Architecture (Provisions for Alpha, ARM, Intel x86,
Macpaul Linafc1ce82011-10-19 20:41:11 +00004060 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
Andy Shevchenkodaab59a2017-07-05 16:25:22 +03004061 Currently supported: ARM, Intel x86, MIPS, NDS32, Nios II, PowerPC).
wdenk2729af92004-05-03 20:45:30 +00004062* Compression Type (uncompressed, gzip, bzip2)
4063* Load Address
4064* Entry Point
4065* Image Name
4066* Image Timestamp
wdenkc6097192002-11-03 00:24:07 +00004067
wdenk2729af92004-05-03 20:45:30 +00004068The header is marked by a special Magic Number, and both the header
4069and the data portions of the image are secured against corruption by
4070CRC32 checksums.
wdenkc6097192002-11-03 00:24:07 +00004071
wdenkc6097192002-11-03 00:24:07 +00004072
wdenk2729af92004-05-03 20:45:30 +00004073Linux Support:
4074==============
wdenkc6097192002-11-03 00:24:07 +00004075
wdenk2729af92004-05-03 20:45:30 +00004076Although U-Boot should support any OS or standalone application
4077easily, the main focus has always been on Linux during the design of
4078U-Boot.
wdenkc6097192002-11-03 00:24:07 +00004079
wdenk2729af92004-05-03 20:45:30 +00004080U-Boot includes many features that so far have been part of some
4081special "boot loader" code within the Linux kernel. Also, any
4082"initrd" images to be used are no longer part of one big Linux image;
4083instead, kernel and "initrd" are separate images. This implementation
4084serves several purposes:
wdenkc6097192002-11-03 00:24:07 +00004085
wdenk2729af92004-05-03 20:45:30 +00004086- the same features can be used for other OS or standalone
4087 applications (for instance: using compressed images to reduce the
4088 Flash memory footprint)
wdenkc6097192002-11-03 00:24:07 +00004089
wdenk2729af92004-05-03 20:45:30 +00004090- it becomes much easier to port new Linux kernel versions because
4091 lots of low-level, hardware dependent stuff are done by U-Boot
wdenkc6097192002-11-03 00:24:07 +00004092
wdenk2729af92004-05-03 20:45:30 +00004093- the same Linux kernel image can now be used with different "initrd"
4094 images; of course this also means that different kernel images can
4095 be run with the same "initrd". This makes testing easier (you don't
4096 have to build a new "zImage.initrd" Linux image when you just
4097 change a file in your "initrd"). Also, a field-upgrade of the
4098 software is easier now.
wdenkc6097192002-11-03 00:24:07 +00004099
wdenkc6097192002-11-03 00:24:07 +00004100
wdenk2729af92004-05-03 20:45:30 +00004101Linux HOWTO:
4102============
wdenkc6097192002-11-03 00:24:07 +00004103
wdenk2729af92004-05-03 20:45:30 +00004104Porting Linux to U-Boot based systems:
4105---------------------------------------
wdenkc6097192002-11-03 00:24:07 +00004106
wdenk2729af92004-05-03 20:45:30 +00004107U-Boot cannot save you from doing all the necessary modifications to
4108configure the Linux device drivers for use with your target hardware
4109(no, we don't intend to provide a full virtual machine interface to
4110Linux :-).
wdenkc6097192002-11-03 00:24:07 +00004111
Stefan Roesea47a12b2010-04-15 16:07:28 +02004112But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot).
wdenkc6097192002-11-03 00:24:07 +00004113
wdenk2729af92004-05-03 20:45:30 +00004114Just make sure your machine specific header file (for instance
4115include/asm-ppc/tqm8xx.h) includes the same definition of the Board
Markus Heidelberg1dc30692008-09-07 20:18:27 +02004116Information structure as we define in include/asm-<arch>/u-boot.h,
4117and make sure that your definition of IMAP_ADDR uses the same value
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02004118as your U-Boot configuration in CONFIG_SYS_IMMR.
wdenkc6097192002-11-03 00:24:07 +00004119
Simon Glass2eb31b12014-06-11 23:29:46 -06004120Note that U-Boot now has a driver model, a unified model for drivers.
4121If you are adding a new driver, plumb it into driver model. If there
4122is no uclass available, you are encouraged to create one. See
4123doc/driver-model.
4124
wdenkc6097192002-11-03 00:24:07 +00004125
wdenk2729af92004-05-03 20:45:30 +00004126Configuring the Linux kernel:
4127-----------------------------
wdenkc6097192002-11-03 00:24:07 +00004128
wdenk2729af92004-05-03 20:45:30 +00004129No specific requirements for U-Boot. Make sure you have some root
4130device (initial ramdisk, NFS) for your target system.
wdenkc6097192002-11-03 00:24:07 +00004131
wdenkc6097192002-11-03 00:24:07 +00004132
wdenk2729af92004-05-03 20:45:30 +00004133Building a Linux Image:
4134-----------------------
wdenkc6097192002-11-03 00:24:07 +00004135
wdenk2729af92004-05-03 20:45:30 +00004136With U-Boot, "normal" build targets like "zImage" or "bzImage" are
4137not used. If you use recent kernel source, a new build target
4138"uImage" will exist which automatically builds an image usable by
4139U-Boot. Most older kernels also have support for a "pImage" target,
4140which was introduced for our predecessor project PPCBoot and uses a
4141100% compatible format.
wdenkc6097192002-11-03 00:24:07 +00004142
wdenk2729af92004-05-03 20:45:30 +00004143Example:
wdenkc6097192002-11-03 00:24:07 +00004144
Holger Freytherab584d62014-08-04 09:26:05 +02004145 make TQM850L_defconfig
wdenk2729af92004-05-03 20:45:30 +00004146 make oldconfig
4147 make dep
4148 make uImage
wdenkc6097192002-11-03 00:24:07 +00004149
wdenk2729af92004-05-03 20:45:30 +00004150The "uImage" build target uses a special tool (in 'tools/mkimage') to
4151encapsulate a compressed Linux kernel image with header information,
4152CRC32 checksum etc. for use with U-Boot. This is what we are doing:
wdenkc6097192002-11-03 00:24:07 +00004153
wdenk2729af92004-05-03 20:45:30 +00004154* build a standard "vmlinux" kernel image (in ELF binary format):
wdenkc6097192002-11-03 00:24:07 +00004155
wdenk2729af92004-05-03 20:45:30 +00004156* convert the kernel into a raw binary image:
wdenkc6097192002-11-03 00:24:07 +00004157
wdenk2729af92004-05-03 20:45:30 +00004158 ${CROSS_COMPILE}-objcopy -O binary \
4159 -R .note -R .comment \
4160 -S vmlinux linux.bin
wdenkc6097192002-11-03 00:24:07 +00004161
wdenk2729af92004-05-03 20:45:30 +00004162* compress the binary image:
wdenkc6097192002-11-03 00:24:07 +00004163
wdenk2729af92004-05-03 20:45:30 +00004164 gzip -9 linux.bin
wdenkc6097192002-11-03 00:24:07 +00004165
wdenk2729af92004-05-03 20:45:30 +00004166* package compressed binary image for U-Boot:
wdenk24ee89b2002-11-03 17:56:27 +00004167
wdenk2729af92004-05-03 20:45:30 +00004168 mkimage -A ppc -O linux -T kernel -C gzip \
4169 -a 0 -e 0 -n "Linux Kernel Image" \
4170 -d linux.bin.gz uImage
wdenk24ee89b2002-11-03 17:56:27 +00004171
wdenk24ee89b2002-11-03 17:56:27 +00004172
wdenk2729af92004-05-03 20:45:30 +00004173The "mkimage" tool can also be used to create ramdisk images for use
4174with U-Boot, either separated from the Linux kernel image, or
4175combined into one file. "mkimage" encapsulates the images with a 64
4176byte header containing information about target architecture,
4177operating system, image type, compression method, entry points, time
4178stamp, CRC32 checksums, etc.
wdenk24ee89b2002-11-03 17:56:27 +00004179
wdenk2729af92004-05-03 20:45:30 +00004180"mkimage" can be called in two ways: to verify existing images and
4181print the header information, or to build new images.
wdenk24ee89b2002-11-03 17:56:27 +00004182
wdenk2729af92004-05-03 20:45:30 +00004183In the first form (with "-l" option) mkimage lists the information
4184contained in the header of an existing U-Boot image; this includes
4185checksum verification:
wdenk24ee89b2002-11-03 17:56:27 +00004186
wdenk2729af92004-05-03 20:45:30 +00004187 tools/mkimage -l image
4188 -l ==> list image header information
wdenk24ee89b2002-11-03 17:56:27 +00004189
wdenk2729af92004-05-03 20:45:30 +00004190The second form (with "-d" option) is used to build a U-Boot image
4191from a "data file" which is used as image payload:
wdenk24ee89b2002-11-03 17:56:27 +00004192
wdenk2729af92004-05-03 20:45:30 +00004193 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
4194 -n name -d data_file image
4195 -A ==> set architecture to 'arch'
4196 -O ==> set operating system to 'os'
4197 -T ==> set image type to 'type'
4198 -C ==> set compression type 'comp'
4199 -a ==> set load address to 'addr' (hex)
4200 -e ==> set entry point to 'ep' (hex)
4201 -n ==> set image name to 'name'
4202 -d ==> use image data from 'datafile'
wdenk24ee89b2002-11-03 17:56:27 +00004203
wdenk69459792004-05-29 16:53:29 +00004204Right now, all Linux kernels for PowerPC systems use the same load
4205address (0x00000000), but the entry point address depends on the
4206kernel version:
wdenkc6097192002-11-03 00:24:07 +00004207
wdenk2729af92004-05-03 20:45:30 +00004208- 2.2.x kernels have the entry point at 0x0000000C,
4209- 2.3.x and later kernels have the entry point at 0x00000000.
wdenkc6097192002-11-03 00:24:07 +00004210
wdenk2729af92004-05-03 20:45:30 +00004211So a typical call to build a U-Boot image would read:
wdenkc6097192002-11-03 00:24:07 +00004212
wdenk2729af92004-05-03 20:45:30 +00004213 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
4214 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
Stefan Roesea47a12b2010-04-15 16:07:28 +02004215 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \
wdenk2729af92004-05-03 20:45:30 +00004216 > examples/uImage.TQM850L
4217 Image Name: 2.4.4 kernel for TQM850L
4218 Created: Wed Jul 19 02:34:59 2000
4219 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4220 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
4221 Load Address: 0x00000000
4222 Entry Point: 0x00000000
wdenkc6097192002-11-03 00:24:07 +00004223
wdenk2729af92004-05-03 20:45:30 +00004224To verify the contents of the image (or check for corruption):
wdenkc6097192002-11-03 00:24:07 +00004225
wdenk2729af92004-05-03 20:45:30 +00004226 -> tools/mkimage -l examples/uImage.TQM850L
4227 Image Name: 2.4.4 kernel for TQM850L
4228 Created: Wed Jul 19 02:34:59 2000
4229 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4230 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
4231 Load Address: 0x00000000
4232 Entry Point: 0x00000000
wdenkc6097192002-11-03 00:24:07 +00004233
wdenk2729af92004-05-03 20:45:30 +00004234NOTE: for embedded systems where boot time is critical you can trade
4235speed for memory and install an UNCOMPRESSED image instead: this
4236needs more space in Flash, but boots much faster since it does not
4237need to be uncompressed:
wdenkc6097192002-11-03 00:24:07 +00004238
Stefan Roesea47a12b2010-04-15 16:07:28 +02004239 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz
wdenk2729af92004-05-03 20:45:30 +00004240 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
4241 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
Stefan Roesea47a12b2010-04-15 16:07:28 +02004242 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \
wdenk2729af92004-05-03 20:45:30 +00004243 > examples/uImage.TQM850L-uncompressed
4244 Image Name: 2.4.4 kernel for TQM850L
4245 Created: Wed Jul 19 02:34:59 2000
4246 Image Type: PowerPC Linux Kernel Image (uncompressed)
4247 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
4248 Load Address: 0x00000000
4249 Entry Point: 0x00000000
wdenkc6097192002-11-03 00:24:07 +00004250
wdenkc6097192002-11-03 00:24:07 +00004251
wdenk2729af92004-05-03 20:45:30 +00004252Similar you can build U-Boot images from a 'ramdisk.image.gz' file
4253when your kernel is intended to use an initial ramdisk:
wdenkdb01a2e2004-04-15 23:14:49 +00004254
wdenk2729af92004-05-03 20:45:30 +00004255 -> tools/mkimage -n 'Simple Ramdisk Image' \
4256 > -A ppc -O linux -T ramdisk -C gzip \
4257 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
4258 Image Name: Simple Ramdisk Image
4259 Created: Wed Jan 12 14:01:50 2000
4260 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
4261 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
4262 Load Address: 0x00000000
4263 Entry Point: 0x00000000
wdenkdb01a2e2004-04-15 23:14:49 +00004264
Guilherme Maciel Ferreiraa804b5c2013-12-01 12:43:11 -07004265The "dumpimage" is a tool to disassemble images built by mkimage. Its "-i"
4266option performs the converse operation of the mkimage's second form (the "-d"
4267option). Given an image built by mkimage, the dumpimage extracts a "data file"
4268from the image:
4269
Guilherme Maciel Ferreiraf41f5b72015-01-15 02:54:40 -02004270 tools/dumpimage -i image -T type -p position data_file
4271 -i ==> extract from the 'image' a specific 'data_file'
4272 -T ==> set image type to 'type'
4273 -p ==> 'position' (starting at 0) of the 'data_file' inside the 'image'
Guilherme Maciel Ferreiraa804b5c2013-12-01 12:43:11 -07004274
wdenkdb01a2e2004-04-15 23:14:49 +00004275
wdenk2729af92004-05-03 20:45:30 +00004276Installing a Linux Image:
4277-------------------------
wdenkdb01a2e2004-04-15 23:14:49 +00004278
wdenk2729af92004-05-03 20:45:30 +00004279To downloading a U-Boot image over the serial (console) interface,
4280you must convert the image to S-Record format:
wdenkdb01a2e2004-04-15 23:14:49 +00004281
wdenk2729af92004-05-03 20:45:30 +00004282 objcopy -I binary -O srec examples/image examples/image.srec
wdenkdb01a2e2004-04-15 23:14:49 +00004283
wdenk2729af92004-05-03 20:45:30 +00004284The 'objcopy' does not understand the information in the U-Boot
4285image header, so the resulting S-Record file will be relative to
4286address 0x00000000. To load it to a given address, you need to
4287specify the target address as 'offset' parameter with the 'loads'
4288command.
wdenkc6097192002-11-03 00:24:07 +00004289
wdenk2729af92004-05-03 20:45:30 +00004290Example: install the image to address 0x40100000 (which on the
4291TQM8xxL is in the first Flash bank):
wdenkc6097192002-11-03 00:24:07 +00004292
wdenk2729af92004-05-03 20:45:30 +00004293 => erase 40100000 401FFFFF
wdenkc6097192002-11-03 00:24:07 +00004294
wdenk2729af92004-05-03 20:45:30 +00004295 .......... done
4296 Erased 8 sectors
wdenkc6097192002-11-03 00:24:07 +00004297
wdenk2729af92004-05-03 20:45:30 +00004298 => loads 40100000
4299 ## Ready for S-Record download ...
4300 ~>examples/image.srec
4301 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
4302 ...
4303 15989 15990 15991 15992
4304 [file transfer complete]
4305 [connected]
4306 ## Start Addr = 0x00000000
wdenkc6097192002-11-03 00:24:07 +00004307
4308
wdenk2729af92004-05-03 20:45:30 +00004309You can check the success of the download using the 'iminfo' command;
Wolfgang Denk218ca722008-03-26 10:40:12 +01004310this includes a checksum verification so you can be sure no data
wdenk2729af92004-05-03 20:45:30 +00004311corruption happened:
wdenkc6097192002-11-03 00:24:07 +00004312
wdenk2729af92004-05-03 20:45:30 +00004313 => imi 40100000
wdenkc6097192002-11-03 00:24:07 +00004314
wdenk2729af92004-05-03 20:45:30 +00004315 ## Checking Image at 40100000 ...
4316 Image Name: 2.2.13 for initrd on TQM850L
4317 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4318 Data Size: 335725 Bytes = 327 kB = 0 MB
4319 Load Address: 00000000
4320 Entry Point: 0000000c
4321 Verifying Checksum ... OK
wdenkc6097192002-11-03 00:24:07 +00004322
4323
wdenk2729af92004-05-03 20:45:30 +00004324Boot Linux:
4325-----------
wdenkc6097192002-11-03 00:24:07 +00004326
wdenk2729af92004-05-03 20:45:30 +00004327The "bootm" command is used to boot an application that is stored in
4328memory (RAM or Flash). In case of a Linux kernel image, the contents
4329of the "bootargs" environment variable is passed to the kernel as
4330parameters. You can check and modify this variable using the
4331"printenv" and "setenv" commands:
wdenkc6097192002-11-03 00:24:07 +00004332
4333
wdenk2729af92004-05-03 20:45:30 +00004334 => printenv bootargs
4335 bootargs=root=/dev/ram
wdenkc6097192002-11-03 00:24:07 +00004336
wdenk2729af92004-05-03 20:45:30 +00004337 => 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 +00004338
wdenk2729af92004-05-03 20:45:30 +00004339 => printenv bootargs
4340 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 +00004341
wdenk2729af92004-05-03 20:45:30 +00004342 => bootm 40020000
4343 ## Booting Linux kernel at 40020000 ...
4344 Image Name: 2.2.13 for NFS on TQM850L
4345 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4346 Data Size: 381681 Bytes = 372 kB = 0 MB
4347 Load Address: 00000000
4348 Entry Point: 0000000c
4349 Verifying Checksum ... OK
4350 Uncompressing Kernel Image ... OK
4351 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
4352 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
4353 time_init: decrementer frequency = 187500000/60
4354 Calibrating delay loop... 49.77 BogoMIPS
4355 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
4356 ...
wdenkc6097192002-11-03 00:24:07 +00004357
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02004358If you want to boot a Linux kernel with initial RAM disk, you pass
wdenk2729af92004-05-03 20:45:30 +00004359the memory addresses of both the kernel and the initrd image (PPBCOOT
4360format!) to the "bootm" command:
wdenkc6097192002-11-03 00:24:07 +00004361
wdenk2729af92004-05-03 20:45:30 +00004362 => imi 40100000 40200000
wdenkc6097192002-11-03 00:24:07 +00004363
wdenk2729af92004-05-03 20:45:30 +00004364 ## Checking Image at 40100000 ...
4365 Image Name: 2.2.13 for initrd on TQM850L
4366 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4367 Data Size: 335725 Bytes = 327 kB = 0 MB
4368 Load Address: 00000000
4369 Entry Point: 0000000c
4370 Verifying Checksum ... OK
wdenkc6097192002-11-03 00:24:07 +00004371
wdenk2729af92004-05-03 20:45:30 +00004372 ## Checking Image at 40200000 ...
4373 Image Name: Simple Ramdisk Image
4374 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
4375 Data Size: 566530 Bytes = 553 kB = 0 MB
4376 Load Address: 00000000
4377 Entry Point: 00000000
4378 Verifying Checksum ... OK
wdenkc6097192002-11-03 00:24:07 +00004379
wdenk2729af92004-05-03 20:45:30 +00004380 => bootm 40100000 40200000
4381 ## Booting Linux kernel at 40100000 ...
4382 Image Name: 2.2.13 for initrd on TQM850L
4383 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4384 Data Size: 335725 Bytes = 327 kB = 0 MB
4385 Load Address: 00000000
4386 Entry Point: 0000000c
4387 Verifying Checksum ... OK
4388 Uncompressing Kernel Image ... OK
4389 ## Loading RAMDisk Image at 40200000 ...
4390 Image Name: Simple Ramdisk Image
4391 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
4392 Data Size: 566530 Bytes = 553 kB = 0 MB
4393 Load Address: 00000000
4394 Entry Point: 00000000
4395 Verifying Checksum ... OK
4396 Loading Ramdisk ... OK
4397 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
4398 Boot arguments: root=/dev/ram
4399 time_init: decrementer frequency = 187500000/60
4400 Calibrating delay loop... 49.77 BogoMIPS
4401 ...
4402 RAMDISK: Compressed image found at block 0
4403 VFS: Mounted root (ext2 filesystem).
wdenkc6097192002-11-03 00:24:07 +00004404
wdenk2729af92004-05-03 20:45:30 +00004405 bash#
wdenkc6097192002-11-03 00:24:07 +00004406
Matthew McClintock02677682006-06-28 10:41:37 -05004407Boot Linux and pass a flat device tree:
4408-----------
4409
4410First, U-Boot must be compiled with the appropriate defines. See the section
4411titled "Linux Kernel Interface" above for a more in depth explanation. The
4412following is an example of how to start a kernel and pass an updated
4413flat device tree:
4414
4415=> print oftaddr
4416oftaddr=0x300000
4417=> print oft
4418oft=oftrees/mpc8540ads.dtb
4419=> tftp $oftaddr $oft
4420Speed: 1000, full duplex
4421Using TSEC0 device
4422TFTP from server 192.168.1.1; our IP address is 192.168.1.101
4423Filename 'oftrees/mpc8540ads.dtb'.
4424Load address: 0x300000
4425Loading: #
4426done
4427Bytes transferred = 4106 (100a hex)
4428=> tftp $loadaddr $bootfile
4429Speed: 1000, full duplex
4430Using TSEC0 device
4431TFTP from server 192.168.1.1; our IP address is 192.168.1.2
4432Filename 'uImage'.
4433Load address: 0x200000
4434Loading:############
4435done
4436Bytes transferred = 1029407 (fb51f hex)
4437=> print loadaddr
4438loadaddr=200000
4439=> print oftaddr
4440oftaddr=0x300000
4441=> bootm $loadaddr - $oftaddr
4442## Booting image at 00200000 ...
Wolfgang Denka9398e02006-11-27 15:32:42 +01004443 Image Name: Linux-2.6.17-dirty
4444 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4445 Data Size: 1029343 Bytes = 1005.2 kB
Matthew McClintock02677682006-06-28 10:41:37 -05004446 Load Address: 00000000
Wolfgang Denka9398e02006-11-27 15:32:42 +01004447 Entry Point: 00000000
Matthew McClintock02677682006-06-28 10:41:37 -05004448 Verifying Checksum ... OK
4449 Uncompressing Kernel Image ... OK
4450Booting using flat device tree at 0x300000
4451Using MPC85xx ADS machine description
4452Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb
4453[snip]
4454
4455
wdenk2729af92004-05-03 20:45:30 +00004456More About U-Boot Image Types:
4457------------------------------
wdenk6069ff22003-02-28 00:49:47 +00004458
wdenk2729af92004-05-03 20:45:30 +00004459U-Boot supports the following image types:
wdenk6069ff22003-02-28 00:49:47 +00004460
wdenk2729af92004-05-03 20:45:30 +00004461 "Standalone Programs" are directly runnable in the environment
4462 provided by U-Boot; it is expected that (if they behave
4463 well) you can continue to work in U-Boot after return from
4464 the Standalone Program.
4465 "OS Kernel Images" are usually images of some Embedded OS which
4466 will take over control completely. Usually these programs
4467 will install their own set of exception handlers, device
4468 drivers, set up the MMU, etc. - this means, that you cannot
4469 expect to re-enter U-Boot except by resetting the CPU.
4470 "RAMDisk Images" are more or less just data blocks, and their
4471 parameters (address, size) are passed to an OS kernel that is
4472 being started.
4473 "Multi-File Images" contain several images, typically an OS
4474 (Linux) kernel image and one or more data images like
4475 RAMDisks. This construct is useful for instance when you want
4476 to boot over the network using BOOTP etc., where the boot
4477 server provides just a single image file, but you want to get
4478 for instance an OS kernel and a RAMDisk image.
stroesec1551ea2003-04-04 15:53:41 +00004479
wdenk2729af92004-05-03 20:45:30 +00004480 "Multi-File Images" start with a list of image sizes, each
4481 image size (in bytes) specified by an "uint32_t" in network
4482 byte order. This list is terminated by an "(uint32_t)0".
4483 Immediately after the terminating 0 follow the images, one by
4484 one, all aligned on "uint32_t" boundaries (size rounded up to
4485 a multiple of 4 bytes).
stroesec1551ea2003-04-04 15:53:41 +00004486
wdenk2729af92004-05-03 20:45:30 +00004487 "Firmware Images" are binary images containing firmware (like
4488 U-Boot or FPGA images) which usually will be programmed to
4489 flash memory.
stroesec1551ea2003-04-04 15:53:41 +00004490
wdenk2729af92004-05-03 20:45:30 +00004491 "Script files" are command sequences that will be executed by
4492 U-Boot's command interpreter; this feature is especially
4493 useful when you configure U-Boot to use a real shell (hush)
4494 as command interpreter.
wdenk6069ff22003-02-28 00:49:47 +00004495
Marek Vasut44f074c2012-03-14 21:52:45 +00004496Booting the Linux zImage:
4497-------------------------
4498
4499On some platforms, it's possible to boot Linux zImage. This is done
4500using the "bootz" command. The syntax of "bootz" command is the same
4501as the syntax of "bootm" command.
4502
Tom Rini8ac28562013-05-16 11:40:11 -04004503Note, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply
Marek Vasut017e1f32012-03-18 11:47:58 +00004504kernel with raw initrd images. The syntax is slightly different, the
4505address of the initrd must be augmented by it's size, in the following
4506format: "<initrd addres>:<initrd size>".
4507
wdenkc6097192002-11-03 00:24:07 +00004508
wdenk2729af92004-05-03 20:45:30 +00004509Standalone HOWTO:
4510=================
wdenkc6097192002-11-03 00:24:07 +00004511
wdenk2729af92004-05-03 20:45:30 +00004512One of the features of U-Boot is that you can dynamically load and
4513run "standalone" applications, which can use some resources of
4514U-Boot like console I/O functions or interrupt services.
wdenkc6097192002-11-03 00:24:07 +00004515
wdenk2729af92004-05-03 20:45:30 +00004516Two simple examples are included with the sources:
wdenkc6097192002-11-03 00:24:07 +00004517
wdenk2729af92004-05-03 20:45:30 +00004518"Hello World" Demo:
4519-------------------
wdenkc6097192002-11-03 00:24:07 +00004520
wdenk2729af92004-05-03 20:45:30 +00004521'examples/hello_world.c' contains a small "Hello World" Demo
4522application; it is automatically compiled when you build U-Boot.
4523It's configured to run at address 0x00040004, so you can play with it
4524like that:
wdenkc6097192002-11-03 00:24:07 +00004525
wdenk2729af92004-05-03 20:45:30 +00004526 => loads
4527 ## Ready for S-Record download ...
4528 ~>examples/hello_world.srec
4529 1 2 3 4 5 6 7 8 9 10 11 ...
4530 [file transfer complete]
4531 [connected]
4532 ## Start Addr = 0x00040004
wdenkc6097192002-11-03 00:24:07 +00004533
wdenk2729af92004-05-03 20:45:30 +00004534 => go 40004 Hello World! This is a test.
4535 ## Starting application at 0x00040004 ...
4536 Hello World
4537 argc = 7
4538 argv[0] = "40004"
4539 argv[1] = "Hello"
4540 argv[2] = "World!"
4541 argv[3] = "This"
4542 argv[4] = "is"
4543 argv[5] = "a"
4544 argv[6] = "test."
4545 argv[7] = "<NULL>"
4546 Hit any key to exit ...
wdenkc6097192002-11-03 00:24:07 +00004547
wdenk2729af92004-05-03 20:45:30 +00004548 ## Application terminated, rc = 0x0
wdenkc6097192002-11-03 00:24:07 +00004549
wdenk2729af92004-05-03 20:45:30 +00004550Another example, which demonstrates how to register a CPM interrupt
4551handler with the U-Boot code, can be found in 'examples/timer.c'.
4552Here, a CPM timer is set up to generate an interrupt every second.
4553The interrupt service routine is trivial, just printing a '.'
4554character, but this is just a demo program. The application can be
4555controlled by the following keys:
wdenkc6097192002-11-03 00:24:07 +00004556
wdenk2729af92004-05-03 20:45:30 +00004557 ? - print current values og the CPM Timer registers
4558 b - enable interrupts and start timer
4559 e - stop timer and disable interrupts
4560 q - quit application
wdenkc6097192002-11-03 00:24:07 +00004561
wdenk2729af92004-05-03 20:45:30 +00004562 => loads
4563 ## Ready for S-Record download ...
4564 ~>examples/timer.srec
4565 1 2 3 4 5 6 7 8 9 10 11 ...
4566 [file transfer complete]
4567 [connected]
4568 ## Start Addr = 0x00040004
wdenkc6097192002-11-03 00:24:07 +00004569
wdenk2729af92004-05-03 20:45:30 +00004570 => go 40004
4571 ## Starting application at 0x00040004 ...
4572 TIMERS=0xfff00980
4573 Using timer 1
4574 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
wdenkc6097192002-11-03 00:24:07 +00004575
wdenk2729af92004-05-03 20:45:30 +00004576Hit 'b':
4577 [q, b, e, ?] Set interval 1000000 us
4578 Enabling timer
4579Hit '?':
4580 [q, b, e, ?] ........
4581 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
4582Hit '?':
4583 [q, b, e, ?] .
4584 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
4585Hit '?':
4586 [q, b, e, ?] .
4587 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
4588Hit '?':
4589 [q, b, e, ?] .
4590 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
4591Hit 'e':
4592 [q, b, e, ?] ...Stopping timer
4593Hit 'q':
4594 [q, b, e, ?] ## Application terminated, rc = 0x0
wdenkc6097192002-11-03 00:24:07 +00004595
4596
wdenk2729af92004-05-03 20:45:30 +00004597Minicom warning:
4598================
wdenk85ec0bc2003-03-31 16:34:49 +00004599
wdenk2729af92004-05-03 20:45:30 +00004600Over time, many people have reported problems when trying to use the
4601"minicom" terminal emulation program for serial download. I (wd)
4602consider minicom to be broken, and recommend not to use it. Under
4603Unix, I recommend to use C-Kermit for general purpose use (and
4604especially for kermit binary protocol download ("loadb" command), and
Karl O. Pince53515a2012-10-01 05:11:56 +00004605use "cu" for S-Record download ("loads" command). See
4606http://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3.
4607for help with kermit.
4608
wdenk85ec0bc2003-03-31 16:34:49 +00004609
wdenk2729af92004-05-03 20:45:30 +00004610Nevertheless, if you absolutely want to use it try adding this
4611configuration to your "File transfer protocols" section:
wdenk52f52c12003-06-19 23:04:19 +00004612
wdenk2729af92004-05-03 20:45:30 +00004613 Name Program Name U/D FullScr IO-Red. Multi
4614 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
4615 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
wdenk52f52c12003-06-19 23:04:19 +00004616
4617
wdenk2729af92004-05-03 20:45:30 +00004618NetBSD Notes:
4619=============
wdenkc6097192002-11-03 00:24:07 +00004620
wdenk2729af92004-05-03 20:45:30 +00004621Starting at version 0.9.2, U-Boot supports NetBSD both as host
4622(build U-Boot) and target system (boots NetBSD/mpc8xx).
wdenkc6097192002-11-03 00:24:07 +00004623
wdenk2729af92004-05-03 20:45:30 +00004624Building requires a cross environment; it is known to work on
4625NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
4626need gmake since the Makefiles are not compatible with BSD make).
4627Note that the cross-powerpc package does not install include files;
4628attempting to build U-Boot will fail because <machine/ansi.h> is
4629missing. This file has to be installed and patched manually:
wdenkc6097192002-11-03 00:24:07 +00004630
wdenk2729af92004-05-03 20:45:30 +00004631 # cd /usr/pkg/cross/powerpc-netbsd/include
4632 # mkdir powerpc
4633 # ln -s powerpc machine
4634 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
4635 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
wdenkc6097192002-11-03 00:24:07 +00004636
wdenk2729af92004-05-03 20:45:30 +00004637Native builds *don't* work due to incompatibilities between native
4638and U-Boot include files.
wdenkc6097192002-11-03 00:24:07 +00004639
wdenk2729af92004-05-03 20:45:30 +00004640Booting assumes that (the first part of) the image booted is a
4641stage-2 loader which in turn loads and then invokes the kernel
4642proper. Loader sources will eventually appear in the NetBSD source
4643tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
wdenk2a8af182005-04-13 10:02:42 +00004644meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
wdenkc6097192002-11-03 00:24:07 +00004645
4646
wdenk2729af92004-05-03 20:45:30 +00004647Implementation Internals:
4648=========================
wdenkc6097192002-11-03 00:24:07 +00004649
wdenk2729af92004-05-03 20:45:30 +00004650The following is not intended to be a complete description of every
4651implementation detail. However, it should help to understand the
4652inner workings of U-Boot and make it easier to port it to custom
4653hardware.
wdenkc6097192002-11-03 00:24:07 +00004654
4655
wdenk2729af92004-05-03 20:45:30 +00004656Initial Stack, Global Data:
4657---------------------------
wdenkc6097192002-11-03 00:24:07 +00004658
wdenk2729af92004-05-03 20:45:30 +00004659The implementation of U-Boot is complicated by the fact that U-Boot
4660starts running out of ROM (flash memory), usually without access to
4661system RAM (because the memory controller is not initialized yet).
4662This means that we don't have writable Data or BSS segments, and BSS
4663is not initialized as zero. To be able to get a C environment working
4664at all, we have to allocate at least a minimal stack. Implementation
4665options for this are defined and restricted by the CPU used: Some CPU
4666models provide on-chip memory (like the IMMR area on MPC8xx and
4667MPC826x processors), on others (parts of) the data cache can be
4668locked as (mis-) used as memory, etc.
wdenkc6097192002-11-03 00:24:07 +00004669
Wolfgang Denk218ca722008-03-26 10:40:12 +01004670 Chris Hallinan posted a good summary of these issues to the
Wolfgang Denk06682362008-12-30 22:56:11 +01004671 U-Boot mailing list:
wdenk43d96162003-03-06 00:02:04 +00004672
wdenk2729af92004-05-03 20:45:30 +00004673 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
4674 From: "Chris Hallinan" <clh@net1plus.com>
4675 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
4676 ...
wdenk43d96162003-03-06 00:02:04 +00004677
wdenk2729af92004-05-03 20:45:30 +00004678 Correct me if I'm wrong, folks, but the way I understand it
4679 is this: Using DCACHE as initial RAM for Stack, etc, does not
4680 require any physical RAM backing up the cache. The cleverness
4681 is that the cache is being used as a temporary supply of
4682 necessary storage before the SDRAM controller is setup. It's
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02004683 beyond the scope of this list to explain the details, but you
wdenk2729af92004-05-03 20:45:30 +00004684 can see how this works by studying the cache architecture and
4685 operation in the architecture and processor-specific manuals.
wdenk43d96162003-03-06 00:02:04 +00004686
wdenk2729af92004-05-03 20:45:30 +00004687 OCM is On Chip Memory, which I believe the 405GP has 4K. It
4688 is another option for the system designer to use as an
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02004689 initial stack/RAM area prior to SDRAM being available. Either
wdenk2729af92004-05-03 20:45:30 +00004690 option should work for you. Using CS 4 should be fine if your
4691 board designers haven't used it for something that would
4692 cause you grief during the initial boot! It is frequently not
4693 used.
wdenk43d96162003-03-06 00:02:04 +00004694
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02004695 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere
wdenk2729af92004-05-03 20:45:30 +00004696 with your processor/board/system design. The default value
4697 you will find in any recent u-boot distribution in
Stefan Roese8a316c92005-08-01 16:49:12 +02004698 walnut.h should work for you. I'd set it to a value larger
wdenk2729af92004-05-03 20:45:30 +00004699 than your SDRAM module. If you have a 64MB SDRAM module, set
4700 it above 400_0000. Just make sure your board has no resources
4701 that are supposed to respond to that address! That code in
4702 start.S has been around a while and should work as is when
4703 you get the config right.
wdenk43d96162003-03-06 00:02:04 +00004704
wdenk2729af92004-05-03 20:45:30 +00004705 -Chris Hallinan
4706 DS4.COM, Inc.
wdenk43d96162003-03-06 00:02:04 +00004707
wdenk2729af92004-05-03 20:45:30 +00004708It is essential to remember this, since it has some impact on the C
4709code for the initialization procedures:
wdenkc6097192002-11-03 00:24:07 +00004710
wdenk2729af92004-05-03 20:45:30 +00004711* Initialized global data (data segment) is read-only. Do not attempt
4712 to write it.
wdenkc6097192002-11-03 00:24:07 +00004713
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08004714* Do not use any uninitialized global data (or implicitly initialized
wdenk2729af92004-05-03 20:45:30 +00004715 as zero data - BSS segment) at all - this is undefined, initiali-
4716 zation is performed later (when relocating to RAM).
wdenkc6097192002-11-03 00:24:07 +00004717
wdenk2729af92004-05-03 20:45:30 +00004718* Stack space is very limited. Avoid big data buffers or things like
4719 that.
wdenkc6097192002-11-03 00:24:07 +00004720
wdenk2729af92004-05-03 20:45:30 +00004721Having only the stack as writable memory limits means we cannot use
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08004722normal global data to share information between the code. But it
wdenk2729af92004-05-03 20:45:30 +00004723turned out that the implementation of U-Boot can be greatly
4724simplified by making a global data structure (gd_t) available to all
4725functions. We could pass a pointer to this data as argument to _all_
4726functions, but this would bloat the code. Instead we use a feature of
4727the GCC compiler (Global Register Variables) to share the data: we
4728place a pointer (gd) to the global data into a register which we
4729reserve for this purpose.
wdenkc6097192002-11-03 00:24:07 +00004730
wdenk2729af92004-05-03 20:45:30 +00004731When choosing a register for such a purpose we are restricted by the
4732relevant (E)ABI specifications for the current architecture, and by
4733GCC's implementation.
wdenkc6097192002-11-03 00:24:07 +00004734
wdenk2729af92004-05-03 20:45:30 +00004735For PowerPC, the following registers have specific use:
4736 R1: stack pointer
Wolfgang Denke7670f62008-02-14 22:43:22 +01004737 R2: reserved for system use
wdenk2729af92004-05-03 20:45:30 +00004738 R3-R4: parameter passing and return values
4739 R5-R10: parameter passing
4740 R13: small data area pointer
4741 R30: GOT pointer
4742 R31: frame pointer
wdenkc6097192002-11-03 00:24:07 +00004743
Joakim Tjernlunde6bee802010-01-19 14:41:58 +01004744 (U-Boot also uses R12 as internal GOT pointer. r12
4745 is a volatile register so r12 needs to be reset when
4746 going back and forth between asm and C)
wdenkc6097192002-11-03 00:24:07 +00004747
Wolfgang Denke7670f62008-02-14 22:43:22 +01004748 ==> U-Boot will use R2 to hold a pointer to the global data
wdenkc6097192002-11-03 00:24:07 +00004749
wdenk2729af92004-05-03 20:45:30 +00004750 Note: on PPC, we could use a static initializer (since the
4751 address of the global data structure is known at compile time),
4752 but it turned out that reserving a register results in somewhat
4753 smaller code - although the code savings are not that big (on
4754 average for all boards 752 bytes for the whole U-Boot image,
4755 624 text + 127 data).
wdenkc6097192002-11-03 00:24:07 +00004756
wdenk2729af92004-05-03 20:45:30 +00004757On ARM, the following registers are used:
wdenkc6097192002-11-03 00:24:07 +00004758
wdenk2729af92004-05-03 20:45:30 +00004759 R0: function argument word/integer result
4760 R1-R3: function argument word
Jeroen Hofstee12eba1b2013-09-21 14:04:42 +02004761 R9: platform specific
4762 R10: stack limit (used only if stack checking is enabled)
wdenk2729af92004-05-03 20:45:30 +00004763 R11: argument (frame) pointer
4764 R12: temporary workspace
4765 R13: stack pointer
4766 R14: link register
4767 R15: program counter
wdenkc6097192002-11-03 00:24:07 +00004768
Jeroen Hofstee12eba1b2013-09-21 14:04:42 +02004769 ==> U-Boot will use R9 to hold a pointer to the global data
4770
4771 Note: on ARM, only R_ARM_RELATIVE relocations are supported.
wdenkc6097192002-11-03 00:24:07 +00004772
Thomas Chou0df01fd2010-05-21 11:08:03 +08004773On Nios II, the ABI is documented here:
4774 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf
4775
4776 ==> U-Boot will use gp to hold a pointer to the global data
4777
4778 Note: on Nios II, we give "-G0" option to gcc and don't use gp
4779 to access small data sections, so gp is free.
4780
Macpaul Linafc1ce82011-10-19 20:41:11 +00004781On NDS32, the following registers are used:
4782
4783 R0-R1: argument/return
4784 R2-R5: argument
4785 R15: temporary register for assembler
4786 R16: trampoline register
4787 R28: frame pointer (FP)
4788 R29: global pointer (GP)
4789 R30: link register (LP)
4790 R31: stack pointer (SP)
4791 PC: program counter (PC)
4792
4793 ==> U-Boot will use R10 to hold a pointer to the global data
4794
Wolfgang Denkd87080b2006-03-31 18:32:53 +02004795NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
4796or current versions of GCC may "optimize" the code too much.
wdenkc6097192002-11-03 00:24:07 +00004797
Rick Chen3fafced2017-12-26 13:55:59 +08004798On RISC-V, the following registers are used:
4799
4800 x0: hard-wired zero (zero)
4801 x1: return address (ra)
4802 x2: stack pointer (sp)
4803 x3: global pointer (gp)
4804 x4: thread pointer (tp)
4805 x5: link register (t0)
4806 x8: frame pointer (fp)
4807 x10-x11: arguments/return values (a0-1)
4808 x12-x17: arguments (a2-7)
4809 x28-31: temporaries (t3-6)
4810 pc: program counter (pc)
4811
4812 ==> U-Boot will use gp to hold a pointer to the global data
4813
wdenk2729af92004-05-03 20:45:30 +00004814Memory Management:
4815------------------
wdenkc6097192002-11-03 00:24:07 +00004816
wdenk2729af92004-05-03 20:45:30 +00004817U-Boot runs in system state and uses physical addresses, i.e. the
4818MMU is not used either for address mapping nor for memory protection.
wdenkc6097192002-11-03 00:24:07 +00004819
wdenk2729af92004-05-03 20:45:30 +00004820The available memory is mapped to fixed addresses using the memory
4821controller. In this process, a contiguous block is formed for each
4822memory type (Flash, SDRAM, SRAM), even when it consists of several
4823physical memory banks.
wdenkc6097192002-11-03 00:24:07 +00004824
wdenk2729af92004-05-03 20:45:30 +00004825U-Boot is installed in the first 128 kB of the first Flash bank (on
4826TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
4827booting and sizing and initializing DRAM, the code relocates itself
4828to the upper end of DRAM. Immediately below the U-Boot code some
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02004829memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN
wdenk2729af92004-05-03 20:45:30 +00004830configuration setting]. Below that, a structure with global Board
4831Info data is placed, followed by the stack (growing downward).
wdenkc6097192002-11-03 00:24:07 +00004832
wdenk2729af92004-05-03 20:45:30 +00004833Additionally, some exception handler code is copied to the low 8 kB
4834of DRAM (0x00000000 ... 0x00001FFF).
wdenkc6097192002-11-03 00:24:07 +00004835
wdenk2729af92004-05-03 20:45:30 +00004836So a typical memory configuration with 16 MB of DRAM could look like
4837this:
wdenkc6097192002-11-03 00:24:07 +00004838
wdenk2729af92004-05-03 20:45:30 +00004839 0x0000 0000 Exception Vector code
4840 :
4841 0x0000 1FFF
4842 0x0000 2000 Free for Application Use
4843 :
4844 :
wdenkc6097192002-11-03 00:24:07 +00004845
wdenk2729af92004-05-03 20:45:30 +00004846 :
4847 :
4848 0x00FB FF20 Monitor Stack (Growing downward)
4849 0x00FB FFAC Board Info Data and permanent copy of global data
4850 0x00FC 0000 Malloc Arena
4851 :
4852 0x00FD FFFF
4853 0x00FE 0000 RAM Copy of Monitor Code
4854 ... eventually: LCD or video framebuffer
4855 ... eventually: pRAM (Protected RAM - unchanged by reset)
4856 0x00FF FFFF [End of RAM]
wdenkc6097192002-11-03 00:24:07 +00004857
4858
wdenk2729af92004-05-03 20:45:30 +00004859System Initialization:
4860----------------------
wdenkc6097192002-11-03 00:24:07 +00004861
wdenk2729af92004-05-03 20:45:30 +00004862In the reset configuration, U-Boot starts at the reset entry point
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02004863(on most PowerPC systems at address 0x00000100). Because of the reset
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08004864configuration for CS0# this is a mirror of the on board Flash memory.
wdenk2729af92004-05-03 20:45:30 +00004865To be able to re-map memory U-Boot then jumps to its link address.
4866To be able to implement the initialization code in C, a (small!)
4867initial stack is set up in the internal Dual Ported RAM (in case CPUs
Heiko Schocher2eb48ff2017-06-07 17:33:10 +02004868which provide such a feature like), or in a locked part of the data
4869cache. After that, U-Boot initializes the CPU core, the caches and
4870the SIU.
wdenkc6097192002-11-03 00:24:07 +00004871
wdenk2729af92004-05-03 20:45:30 +00004872Next, all (potentially) available memory banks are mapped using a
4873preliminary mapping. For example, we put them on 512 MB boundaries
4874(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
4875on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
4876programmed for SDRAM access. Using the temporary configuration, a
4877simple memory test is run that determines the size of the SDRAM
4878banks.
wdenkc6097192002-11-03 00:24:07 +00004879
wdenk2729af92004-05-03 20:45:30 +00004880When there is more than one SDRAM bank, and the banks are of
4881different size, the largest is mapped first. For equal size, the first
4882bank (CS2#) is mapped first. The first mapping is always for address
48830x00000000, with any additional banks following immediately to create
4884contiguous memory starting from 0.
wdenkc6097192002-11-03 00:24:07 +00004885
wdenk2729af92004-05-03 20:45:30 +00004886Then, the monitor installs itself at the upper end of the SDRAM area
4887and allocates memory for use by malloc() and for the global Board
4888Info data; also, the exception vector code is copied to the low RAM
4889pages, and the final stack is set up.
wdenkc6097192002-11-03 00:24:07 +00004890
wdenk2729af92004-05-03 20:45:30 +00004891Only after this relocation will you have a "normal" C environment;
4892until that you are restricted in several ways, mostly because you are
4893running from ROM, and because the code will have to be relocated to a
4894new address in RAM.
wdenkc6097192002-11-03 00:24:07 +00004895
4896
wdenk2729af92004-05-03 20:45:30 +00004897U-Boot Porting Guide:
4898----------------------
wdenkc6097192002-11-03 00:24:07 +00004899
wdenk2729af92004-05-03 20:45:30 +00004900[Based on messages by Jerry Van Baren in the U-Boot-Users mailing
4901list, October 2002]
wdenkc6097192002-11-03 00:24:07 +00004902
4903
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04004904int main(int argc, char *argv[])
wdenk2729af92004-05-03 20:45:30 +00004905{
4906 sighandler_t no_more_time;
wdenkc6097192002-11-03 00:24:07 +00004907
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04004908 signal(SIGALRM, no_more_time);
4909 alarm(PROJECT_DEADLINE - toSec (3 * WEEK));
wdenkc6097192002-11-03 00:24:07 +00004910
wdenk2729af92004-05-03 20:45:30 +00004911 if (available_money > available_manpower) {
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04004912 Pay consultant to port U-Boot;
wdenkc6097192002-11-03 00:24:07 +00004913 return 0;
4914 }
4915
wdenk2729af92004-05-03 20:45:30 +00004916 Download latest U-Boot source;
4917
Wolfgang Denk06682362008-12-30 22:56:11 +01004918 Subscribe to u-boot mailing list;
wdenk2729af92004-05-03 20:45:30 +00004919
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04004920 if (clueless)
4921 email("Hi, I am new to U-Boot, how do I get started?");
wdenkc6097192002-11-03 00:24:07 +00004922
wdenk2729af92004-05-03 20:45:30 +00004923 while (learning) {
4924 Read the README file in the top level directory;
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04004925 Read http://www.denx.de/twiki/bin/view/DULG/Manual;
4926 Read applicable doc/*.README;
wdenk2729af92004-05-03 20:45:30 +00004927 Read the source, Luke;
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04004928 /* find . -name "*.[chS]" | xargs grep -i <keyword> */
wdenk2729af92004-05-03 20:45:30 +00004929 }
wdenkc6097192002-11-03 00:24:07 +00004930
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04004931 if (available_money > toLocalCurrency ($2500))
4932 Buy a BDI3000;
4933 else
wdenk2729af92004-05-03 20:45:30 +00004934 Add a lot of aggravation and time;
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04004935
4936 if (a similar board exists) { /* hopefully... */
4937 cp -a board/<similar> board/<myboard>
4938 cp include/configs/<similar>.h include/configs/<myboard>.h
4939 } else {
4940 Create your own board support subdirectory;
4941 Create your own board include/configs/<myboard>.h file;
wdenk2729af92004-05-03 20:45:30 +00004942 }
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04004943 Edit new board/<myboard> files
4944 Edit new include/configs/<myboard>.h
wdenkc6097192002-11-03 00:24:07 +00004945
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04004946 while (!accepted) {
4947 while (!running) {
4948 do {
4949 Add / modify source code;
4950 } until (compiles);
4951 Debug;
4952 if (clueless)
4953 email("Hi, I am having problems...");
4954 }
4955 Send patch file to the U-Boot email list;
4956 if (reasonable critiques)
4957 Incorporate improvements from email list code review;
4958 else
4959 Defend code as written;
wdenk2729af92004-05-03 20:45:30 +00004960 }
wdenkc6097192002-11-03 00:24:07 +00004961
wdenk2729af92004-05-03 20:45:30 +00004962 return 0;
4963}
4964
4965void no_more_time (int sig)
4966{
4967 hire_a_guru();
4968}
wdenkc6097192002-11-03 00:24:07 +00004969
4970
wdenk2729af92004-05-03 20:45:30 +00004971Coding Standards:
4972-----------------
wdenkc6097192002-11-03 00:24:07 +00004973
wdenk2729af92004-05-03 20:45:30 +00004974All contributions to U-Boot should conform to the Linux kernel
Baruch Siach659208d2017-12-10 17:34:35 +02004975coding style; see the kernel coding style guide at
4976https://www.kernel.org/doc/html/latest/process/coding-style.html, and the
4977script "scripts/Lindent" in your Linux kernel source directory.
wdenk2729af92004-05-03 20:45:30 +00004978
Detlev Zundel2c051652006-09-01 15:39:02 +02004979Source files originating from a different project (for example the
4980MTD subsystem) are generally exempt from these guidelines and are not
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08004981reformatted to ease subsequent migration to newer versions of those
Detlev Zundel2c051652006-09-01 15:39:02 +02004982sources.
4983
4984Please note that U-Boot is implemented in C (and to some small parts in
4985Assembler); no C++ is used, so please do not use C++ style comments (//)
4986in your code.
wdenk2729af92004-05-03 20:45:30 +00004987
4988Please also stick to the following formatting rules:
4989- remove any trailing white space
Wolfgang Denk7ca92962011-07-27 10:59:55 +00004990- use TAB characters for indentation and vertical alignment, not spaces
wdenk2729af92004-05-03 20:45:30 +00004991- make sure NOT to use DOS '\r\n' line feeds
Wolfgang Denk7ca92962011-07-27 10:59:55 +00004992- do not add more than 2 consecutive empty lines to source files
wdenk2729af92004-05-03 20:45:30 +00004993- do not add trailing empty lines to source files
4994
4995Submissions which do not conform to the standards may be returned
4996with a request to reformat the changes.
wdenkc6097192002-11-03 00:24:07 +00004997
4998
wdenk2729af92004-05-03 20:45:30 +00004999Submitting Patches:
5000-------------------
wdenkc6097192002-11-03 00:24:07 +00005001
wdenk2729af92004-05-03 20:45:30 +00005002Since the number of patches for U-Boot is growing, we need to
5003establish some rules. Submissions which do not conform to these rules
5004may be rejected, even when they contain important and valuable stuff.
wdenkc6097192002-11-03 00:24:07 +00005005
Magnus Lilja0d28f342008-08-06 19:32:33 +02005006Please see http://www.denx.de/wiki/U-Boot/Patches for details.
Wolfgang Denk218ca722008-03-26 10:40:12 +01005007
Wolfgang Denk06682362008-12-30 22:56:11 +01005008Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>;
S. Lockwood-Childs1dade182017-11-14 22:56:42 -08005009see https://lists.denx.de/listinfo/u-boot
Wolfgang Denk06682362008-12-30 22:56:11 +01005010
wdenk2729af92004-05-03 20:45:30 +00005011When you send a patch, please include the following information with
5012it:
wdenkc6097192002-11-03 00:24:07 +00005013
wdenk2729af92004-05-03 20:45:30 +00005014* For bug fixes: a description of the bug and how your patch fixes
5015 this bug. Please try to include a way of demonstrating that the
5016 patch actually fixes something.
wdenkc6097192002-11-03 00:24:07 +00005017
wdenk2729af92004-05-03 20:45:30 +00005018* For new features: a description of the feature and your
5019 implementation.
wdenkc6097192002-11-03 00:24:07 +00005020
wdenk2729af92004-05-03 20:45:30 +00005021* A CHANGELOG entry as plaintext (separate from the patch)
5022
Robert P. J. Day7207b362015-12-19 07:16:10 -05005023* For major contributions, add a MAINTAINERS file with your
5024 information and associated file and directory references.
wdenk2729af92004-05-03 20:45:30 +00005025
Albert ARIBAUD27af9302013-09-11 15:52:51 +02005026* When you add support for a new board, don't forget to add a
5027 maintainer e-mail address to the boards.cfg file, too.
wdenk2729af92004-05-03 20:45:30 +00005028
5029* If your patch adds new configuration options, don't forget to
5030 document these in the README file.
5031
Wolfgang Denk218ca722008-03-26 10:40:12 +01005032* The patch itself. If you are using git (which is *strongly*
5033 recommended) you can easily generate the patch using the
Wolfgang Denk7ca92962011-07-27 10:59:55 +00005034 "git format-patch". If you then use "git send-email" to send it to
Wolfgang Denk218ca722008-03-26 10:40:12 +01005035 the U-Boot mailing list, you will avoid most of the common problems
5036 with some other mail clients.
wdenk2729af92004-05-03 20:45:30 +00005037
Wolfgang Denk218ca722008-03-26 10:40:12 +01005038 If you cannot use git, use "diff -purN OLD NEW". If your version of
5039 diff does not support these options, then get the latest version of
5040 GNU diff.
wdenk2729af92004-05-03 20:45:30 +00005041
Wolfgang Denk218ca722008-03-26 10:40:12 +01005042 The current directory when running this command shall be the parent
5043 directory of the U-Boot source tree (i. e. please make sure that
5044 your patch includes sufficient directory information for the
5045 affected files).
5046
5047 We prefer patches as plain text. MIME attachments are discouraged,
5048 and compressed attachments must not be used.
wdenk2729af92004-05-03 20:45:30 +00005049
5050* If one logical set of modifications affects or creates several
5051 files, all these changes shall be submitted in a SINGLE patch file.
5052
5053* Changesets that contain different, unrelated modifications shall be
5054 submitted as SEPARATE patches, one patch per changeset.
5055
5056
5057Notes:
5058
Simon Glass6de80f22016-07-27 20:33:08 -06005059* Before sending the patch, run the buildman script on your patched
wdenk2729af92004-05-03 20:45:30 +00005060 source tree and make sure that no errors or warnings are reported
5061 for any of the boards.
5062
5063* Keep your modifications to the necessary minimum: A patch
5064 containing several unrelated changes or arbitrary reformats will be
5065 returned with a request to re-formatting / split it.
5066
5067* If you modify existing code, make sure that your new code does not
5068 add to the memory footprint of the code ;-) Small is beautiful!
5069 When adding new features, these should compile conditionally only
5070 (using #ifdef), and the resulting code with the new feature
5071 disabled must not need more memory than the old code without your
5072 modification.
wdenk90dc6702005-05-03 14:12:25 +00005073
Wolfgang Denk06682362008-12-30 22:56:11 +01005074* Remember that there is a size limit of 100 kB per message on the
5075 u-boot mailing list. Bigger patches will be moderated. If they are
5076 reasonable and not too big, they will be acknowledged. But patches
5077 bigger than the size limit should be avoided.