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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.
Naoki Hayama6681bbb2020-10-08 13:16:18 +090054Please see https://lists.denx.de/pipermail/u-boot and
55https://marc.info/?l=u-boot
wdenkc6097192002-11-03 00:24:07 +000056
Wolfgang Denk218ca722008-03-26 10:40:12 +010057Where to get source code:
58=========================
59
Robert P. J. Day7207b362015-12-19 07:16:10 -050060The U-Boot source code is maintained in the Git repository at
Naoki Hayamac4bd51e2020-10-08 13:16:25 +090061https://gitlab.denx.de/u-boot/u-boot.git ; you can browse it online at
62https://gitlab.denx.de/u-boot/u-boot
Wolfgang Denk218ca722008-03-26 10:40:12 +010063
Naoki Hayamac4bd51e2020-10-08 13:16:25 +090064The "Tags" links on this page allow you to download tarballs of
Marcel Ziswiler11ccc332008-07-09 08:17:15 +020065any version you might be interested in. Official releases are also
Naoki Hayamac4bd51e2020-10-08 13:16:25 +090066available from the DENX file server through HTTPS or FTP.
67https://ftp.denx.de/pub/u-boot/
68ftp://ftp.denx.de/pub/u-boot/
Wolfgang Denk218ca722008-03-26 10:40:12 +010069
70
wdenkc6097192002-11-03 00:24:07 +000071Where we come from:
72===================
73
74- start from 8xxrom sources
Naoki Hayama047f6ec2020-10-08 13:17:16 +090075- create PPCBoot project (https://sourceforge.net/projects/ppcboot)
wdenkc6097192002-11-03 00:24:07 +000076- clean up code
77- make it easier to add custom boards
78- make it possible to add other [PowerPC] CPUs
79- extend functions, especially:
80 * Provide extended interface to Linux boot loader
81 * S-Record download
82 * network boot
Simon Glass9e5616d2019-08-01 09:47:14 -060083 * ATA disk / SCSI ... boot
Naoki Hayama047f6ec2020-10-08 13:17:16 +090084- create ARMBoot project (https://sourceforge.net/projects/armboot)
wdenkc6097192002-11-03 00:24:07 +000085- add other CPU families (starting with ARM)
Naoki Hayama047f6ec2020-10-08 13:17:16 +090086- create U-Boot project (https://sourceforge.net/projects/u-boot)
87- current project page: see https://www.denx.de/wiki/U-Boot
wdenk24ee89b2002-11-03 17:56:27 +000088
89
90Names and Spelling:
91===================
92
93The "official" name of this project is "Das U-Boot". The spelling
94"U-Boot" shall be used in all written text (documentation, comments
95in source files etc.). Example:
96
97 This is the README file for the U-Boot project.
98
99File names etc. shall be based on the string "u-boot". Examples:
100
101 include/asm-ppc/u-boot.h
102
103 #include <asm/u-boot.h>
104
105Variable names, preprocessor constants etc. shall be either based on
106the string "u_boot" or on "U_BOOT". Example:
107
108 U_BOOT_VERSION u_boot_logo
109 IH_OS_U_BOOT u_boot_hush_start
wdenkc6097192002-11-03 00:24:07 +0000110
111
wdenk93f19cc2002-12-17 17:55:09 +0000112Versioning:
113===========
114
Thomas Weber360d8832010-09-28 08:06:25 +0200115Starting with the release in October 2008, the names of the releases
116were changed from numerical release numbers without deeper meaning
117into a time stamp based numbering. Regular releases are identified by
118names consisting of the calendar year and month of the release date.
119Additional fields (if present) indicate release candidates or bug fix
120releases in "stable" maintenance trees.
wdenk93f19cc2002-12-17 17:55:09 +0000121
Thomas Weber360d8832010-09-28 08:06:25 +0200122Examples:
Wolfgang Denkc0f40852011-10-26 10:21:21 +0000123 U-Boot v2009.11 - Release November 2009
Thomas Weber360d8832010-09-28 08:06:25 +0200124 U-Boot v2009.11.1 - Release 1 in version November 2009 stable tree
Jelle van der Waa0de21ec2016-10-30 17:30:30 +0100125 U-Boot v2010.09-rc1 - Release candidate 1 for September 2010 release
wdenk93f19cc2002-12-17 17:55:09 +0000126
127
wdenkc6097192002-11-03 00:24:07 +0000128Directory Hierarchy:
129====================
130
Peter Tyser8d321b82010-04-12 22:28:21 -0500131/arch Architecture specific files
Masahiro Yamada6eae68e2014-03-07 18:02:02 +0900132 /arc Files generic to ARC architecture
Peter Tyser8d321b82010-04-12 22:28:21 -0500133 /arm Files generic to ARM architecture
Peter Tyser8d321b82010-04-12 22:28:21 -0500134 /m68k Files generic to m68k architecture
Peter Tyser8d321b82010-04-12 22:28:21 -0500135 /microblaze Files generic to microblaze architecture
Peter Tyser8d321b82010-04-12 22:28:21 -0500136 /mips Files generic to MIPS architecture
Macpaul Linafc1ce82011-10-19 20:41:11 +0000137 /nds32 Files generic to NDS32 architecture
Peter Tyser8d321b82010-04-12 22:28:21 -0500138 /nios2 Files generic to Altera NIOS2 architecture
Stefan Roesea47a12b2010-04-15 16:07:28 +0200139 /powerpc Files generic to PowerPC architecture
Rick Chen3fafced2017-12-26 13:55:59 +0800140 /riscv Files generic to RISC-V architecture
Robert P. J. Day7207b362015-12-19 07:16:10 -0500141 /sandbox Files generic to HW-independent "sandbox"
Peter Tyser8d321b82010-04-12 22:28:21 -0500142 /sh Files generic to SH architecture
Robert P. J. Day33c77312013-09-15 18:34:15 -0400143 /x86 Files generic to x86 architecture
Naoki Hayamae4eb3132020-10-08 13:16:38 +0900144 /xtensa Files generic to Xtensa architecture
Peter Tyser8d321b82010-04-12 22:28:21 -0500145/api Machine/arch independent API for external apps
146/board Board dependent files
Xu Ziyuan740f7e52016-08-26 19:54:49 +0800147/cmd U-Boot commands functions
Peter Tyser8d321b82010-04-12 22:28:21 -0500148/common Misc architecture independent functions
Robert P. J. Day7207b362015-12-19 07:16:10 -0500149/configs Board default configuration files
Peter Tyser8d321b82010-04-12 22:28:21 -0500150/disk Code for disk drive partition handling
151/doc Documentation (don't expect too much)
152/drivers Commonly used device drivers
Robert P. J. Day33c77312013-09-15 18:34:15 -0400153/dts Contains Makefile for building internal U-Boot fdt.
Naoki Hayamae4eb3132020-10-08 13:16:38 +0900154/env Environment files
Peter Tyser8d321b82010-04-12 22:28:21 -0500155/examples Example code for standalone applications, etc.
156/fs Filesystem code (cramfs, ext2, jffs2, etc.)
157/include Header Files
Robert P. J. Day7207b362015-12-19 07:16:10 -0500158/lib Library routines generic to all architectures
159/Licenses Various license files
Peter Tyser8d321b82010-04-12 22:28:21 -0500160/net Networking code
161/post Power On Self Test
Robert P. J. Day7207b362015-12-19 07:16:10 -0500162/scripts Various build scripts and Makefiles
163/test Various unit test files
Peter Tyser8d321b82010-04-12 22:28:21 -0500164/tools Tools to build S-Record or U-Boot images, etc.
wdenkc6097192002-11-03 00:24:07 +0000165
wdenkc6097192002-11-03 00:24:07 +0000166Software Configuration:
167=======================
168
169Configuration is usually done using C preprocessor defines; the
170rationale behind that is to avoid dead code whenever possible.
171
172There are two classes of configuration variables:
173
174* Configuration _OPTIONS_:
175 These are selectable by the user and have names beginning with
176 "CONFIG_".
177
178* Configuration _SETTINGS_:
179 These depend on the hardware etc. and should not be meddled with if
180 you don't know what you're doing; they have names beginning with
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +0200181 "CONFIG_SYS_".
wdenkc6097192002-11-03 00:24:07 +0000182
Robert P. J. Day7207b362015-12-19 07:16:10 -0500183Previously, all configuration was done by hand, which involved creating
184symbolic links and editing configuration files manually. More recently,
185U-Boot has added the Kbuild infrastructure used by the Linux kernel,
186allowing you to use the "make menuconfig" command to configure your
187build.
wdenkc6097192002-11-03 00:24:07 +0000188
189
190Selection of Processor Architecture and Board Type:
191---------------------------------------------------
192
193For all supported boards there are ready-to-use default
Holger Freytherab584d62014-08-04 09:26:05 +0200194configurations available; just type "make <board_name>_defconfig".
wdenkc6097192002-11-03 00:24:07 +0000195
196Example: For a TQM823L module type:
197
198 cd u-boot
Holger Freytherab584d62014-08-04 09:26:05 +0200199 make TQM823L_defconfig
wdenkc6097192002-11-03 00:24:07 +0000200
Robert P. J. Day7207b362015-12-19 07:16:10 -0500201Note: If you're looking for the default configuration file for a board
202you're sure used to be there but is now missing, check the file
203doc/README.scrapyard for a list of no longer supported boards.
wdenkc6097192002-11-03 00:24:07 +0000204
Simon Glass75b3c3a2014-03-22 17:12:59 -0600205Sandbox Environment:
206--------------------
207
208U-Boot can be built natively to run on a Linux host using the 'sandbox'
209board. This allows feature development which is not board- or architecture-
210specific to be undertaken on a native platform. The sandbox is also used to
211run some of U-Boot's tests.
212
Naoki Hayamabbb140e2020-10-08 13:16:58 +0900213See doc/arch/sandbox.rst for more details.
Simon Glass75b3c3a2014-03-22 17:12:59 -0600214
215
Simon Glassdb910352015-03-03 08:03:00 -0700216Board Initialisation Flow:
217--------------------------
218
219This is the intended start-up flow for boards. This should apply for both
Robert P. J. Day7207b362015-12-19 07:16:10 -0500220SPL and U-Boot proper (i.e. they both follow the same rules).
Simon Glassdb910352015-03-03 08:03:00 -0700221
Robert P. J. Day7207b362015-12-19 07:16:10 -0500222Note: "SPL" stands for "Secondary Program Loader," which is explained in
223more detail later in this file.
224
225At present, SPL mostly uses a separate code path, but the function names
226and roles of each function are the same. Some boards or architectures
227may not conform to this. At least most ARM boards which use
228CONFIG_SPL_FRAMEWORK conform to this.
229
230Execution typically starts with an architecture-specific (and possibly
231CPU-specific) start.S file, such as:
232
233 - arch/arm/cpu/armv7/start.S
234 - arch/powerpc/cpu/mpc83xx/start.S
235 - arch/mips/cpu/start.S
236
237and so on. From there, three functions are called; the purpose and
238limitations of each of these functions are described below.
Simon Glassdb910352015-03-03 08:03:00 -0700239
240lowlevel_init():
241 - purpose: essential init to permit execution to reach board_init_f()
242 - no global_data or BSS
243 - there is no stack (ARMv7 may have one but it will soon be removed)
244 - must not set up SDRAM or use console
245 - must only do the bare minimum to allow execution to continue to
246 board_init_f()
247 - this is almost never needed
248 - return normally from this function
249
250board_init_f():
251 - purpose: set up the machine ready for running board_init_r():
252 i.e. SDRAM and serial UART
253 - global_data is available
254 - stack is in SRAM
255 - BSS is not available, so you cannot use global/static variables,
256 only stack variables and global_data
257
258 Non-SPL-specific notes:
259 - dram_init() is called to set up DRAM. If already done in SPL this
260 can do nothing
261
262 SPL-specific notes:
263 - you can override the entire board_init_f() function with your own
264 version as needed.
265 - preloader_console_init() can be called here in extremis
266 - should set up SDRAM, and anything needed to make the UART work
Naoki Hayama499696e2020-09-24 15:57:19 +0900267 - there is no need to clear BSS, it will be done by crt0.S
Andreas Dannenberg14254652019-08-08 12:54:49 -0500268 - for specific scenarios on certain architectures an early BSS *can*
269 be made available (via CONFIG_SPL_EARLY_BSS by moving the clearing
270 of BSS prior to entering board_init_f()) but doing so is discouraged.
271 Instead it is strongly recommended to architect any code changes
272 or additions such to not depend on the availability of BSS during
273 board_init_f() as indicated in other sections of this README to
274 maintain compatibility and consistency across the entire code base.
Simon Glassdb910352015-03-03 08:03:00 -0700275 - must return normally from this function (don't call board_init_r()
276 directly)
277
278Here the BSS is cleared. For SPL, if CONFIG_SPL_STACK_R is defined, then at
279this point the stack and global_data are relocated to below
280CONFIG_SPL_STACK_R_ADDR. For non-SPL, U-Boot is relocated to run at the top of
281memory.
282
283board_init_r():
284 - purpose: main execution, common code
285 - global_data is available
286 - SDRAM is available
287 - BSS is available, all static/global variables can be used
288 - execution eventually continues to main_loop()
289
290 Non-SPL-specific notes:
291 - U-Boot is relocated to the top of memory and is now running from
292 there.
293
294 SPL-specific notes:
295 - stack is optionally in SDRAM, if CONFIG_SPL_STACK_R is defined and
296 CONFIG_SPL_STACK_R_ADDR points into SDRAM
297 - preloader_console_init() can be called here - typically this is
Ley Foon Tan0680f1b2017-05-03 17:13:32 +0800298 done by selecting CONFIG_SPL_BOARD_INIT and then supplying a
Simon Glassdb910352015-03-03 08:03:00 -0700299 spl_board_init() function containing this call
300 - loads U-Boot or (in falcon mode) Linux
301
302
303
wdenkc6097192002-11-03 00:24:07 +0000304Configuration Options:
305----------------------
306
307Configuration depends on the combination of board and CPU type; all
308such information is kept in a configuration file
309"include/configs/<board_name>.h".
310
311Example: For a TQM823L module, all configuration settings are in
312"include/configs/TQM823L.h".
313
314
wdenk7f6c2cb2002-11-10 22:06:23 +0000315Many of the options are named exactly as the corresponding Linux
316kernel configuration options. The intention is to make it easier to
317build a config tool - later.
318
Ashish Kumar63b23162017-08-11 11:09:14 +0530319- ARM Platform Bus Type(CCI):
320 CoreLink Cache Coherent Interconnect (CCI) is ARM BUS which
321 provides full cache coherency between two clusters of multi-core
322 CPUs and I/O coherency for devices and I/O masters
323
324 CONFIG_SYS_FSL_HAS_CCI400
325
326 Defined For SoC that has cache coherent interconnect
327 CCN-400
wdenk7f6c2cb2002-11-10 22:06:23 +0000328
Ashish Kumarc055cee2017-08-18 10:54:36 +0530329 CONFIG_SYS_FSL_HAS_CCN504
330
331 Defined for SoC that has cache coherent interconnect CCN-504
332
wdenkc6097192002-11-03 00:24:07 +0000333The following options need to be configured:
334
Kim Phillips26281142007-08-10 13:28:25 -0500335- CPU Type: Define exactly one, e.g. CONFIG_MPC85XX.
wdenkc6097192002-11-03 00:24:07 +0000336
Kim Phillips26281142007-08-10 13:28:25 -0500337- Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS.
Wolfgang Denk6ccec442006-10-24 14:42:37 +0200338
Kumar Gala66412c62011-02-18 05:40:54 -0600339- 85xx CPU Options:
York Sunffd06e02012-10-08 07:44:30 +0000340 CONFIG_SYS_PPC64
341
342 Specifies that the core is a 64-bit PowerPC implementation (implements
343 the "64" category of the Power ISA). This is necessary for ePAPR
344 compliance, among other possible reasons.
345
Kumar Gala66412c62011-02-18 05:40:54 -0600346 CONFIG_SYS_FSL_TBCLK_DIV
347
348 Defines the core time base clock divider ratio compared to the
349 system clock. On most PQ3 devices this is 8, on newer QorIQ
350 devices it can be 16 or 32. The ratio varies from SoC to Soc.
351
Kumar Gala8f290842011-05-20 00:39:21 -0500352 CONFIG_SYS_FSL_PCIE_COMPAT
353
354 Defines the string to utilize when trying to match PCIe device
355 tree nodes for the given platform.
356
Scott Wood33eee332012-08-14 10:14:53 +0000357 CONFIG_SYS_FSL_ERRATUM_A004510
358
359 Enables a workaround for erratum A004510. If set,
360 then CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV and
361 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY must be set.
362
363 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV
364 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 (optional)
365
366 Defines one or two SoC revisions (low 8 bits of SVR)
367 for which the A004510 workaround should be applied.
368
369 The rest of SVR is either not relevant to the decision
370 of whether the erratum is present (e.g. p2040 versus
371 p2041) or is implied by the build target, which controls
372 whether CONFIG_SYS_FSL_ERRATUM_A004510 is set.
373
374 See Freescale App Note 4493 for more information about
375 this erratum.
376
Prabhakar Kushwaha74fa22e2013-04-16 13:27:44 +0530377 CONFIG_A003399_NOR_WORKAROUND
378 Enables a workaround for IFC erratum A003399. It is only
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -0800379 required during NOR boot.
Prabhakar Kushwaha74fa22e2013-04-16 13:27:44 +0530380
Prabhakar Kushwaha9f074e62014-10-29 22:33:09 +0530381 CONFIG_A008044_WORKAROUND
382 Enables a workaround for T1040/T1042 erratum A008044. It is only
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -0800383 required during NAND boot and valid for Rev 1.0 SoC revision
Prabhakar Kushwaha9f074e62014-10-29 22:33:09 +0530384
Scott Wood33eee332012-08-14 10:14:53 +0000385 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY
386
387 This is the value to write into CCSR offset 0x18600
388 according to the A004510 workaround.
389
Priyanka Jain64501c62013-07-02 09:21:04 +0530390 CONFIG_SYS_FSL_DSP_DDR_ADDR
391 This value denotes start offset of DDR memory which is
392 connected exclusively to the DSP cores.
393
Priyanka Jain765b0bd2013-04-04 09:31:54 +0530394 CONFIG_SYS_FSL_DSP_M2_RAM_ADDR
395 This value denotes start offset of M2 memory
396 which is directly connected to the DSP core.
397
Priyanka Jain64501c62013-07-02 09:21:04 +0530398 CONFIG_SYS_FSL_DSP_M3_RAM_ADDR
399 This value denotes start offset of M3 memory which is directly
400 connected to the DSP core.
401
Priyanka Jain765b0bd2013-04-04 09:31:54 +0530402 CONFIG_SYS_FSL_DSP_CCSRBAR_DEFAULT
403 This value denotes start offset of DSP CCSR space.
404
Priyanka Jainb1359912013-12-17 14:25:52 +0530405 CONFIG_SYS_FSL_SINGLE_SOURCE_CLK
406 Single Source Clock is clocking mode present in some of FSL SoC's.
407 In this mode, a single differential clock is used to supply
408 clocks to the sysclock, ddrclock and usbclock.
409
Aneesh Bansalfb4a2402014-03-18 23:40:26 +0530410 CONFIG_SYS_CPC_REINIT_F
411 This CONFIG is defined when the CPC is configured as SRAM at the
Bin Menga1875592016-02-05 19:30:11 -0800412 time of U-Boot entry and is required to be re-initialized.
Aneesh Bansalfb4a2402014-03-18 23:40:26 +0530413
Tang Yuantianaade2002014-04-17 15:33:46 +0800414 CONFIG_DEEP_SLEEP
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -0800415 Indicates this SoC supports deep sleep feature. If deep sleep is
Tang Yuantianaade2002014-04-17 15:33:46 +0800416 supported, core will start to execute uboot when wakes up.
417
Daniel Schwierzeck6cb461b2012-04-02 02:57:56 +0000418- Generic CPU options:
419 CONFIG_SYS_BIG_ENDIAN, CONFIG_SYS_LITTLE_ENDIAN
420
421 Defines the endianess of the CPU. Implementation of those
422 values is arch specific.
423
York Sun5614e712013-09-30 09:22:09 -0700424 CONFIG_SYS_FSL_DDR
425 Freescale DDR driver in use. This type of DDR controller is
426 found in mpc83xx, mpc85xx, mpc86xx as well as some ARM core
427 SoCs.
428
429 CONFIG_SYS_FSL_DDR_ADDR
430 Freescale DDR memory-mapped register base.
431
432 CONFIG_SYS_FSL_DDR_EMU
433 Specify emulator support for DDR. Some DDR features such as
434 deskew training are not available.
435
436 CONFIG_SYS_FSL_DDRC_GEN1
437 Freescale DDR1 controller.
438
439 CONFIG_SYS_FSL_DDRC_GEN2
440 Freescale DDR2 controller.
441
442 CONFIG_SYS_FSL_DDRC_GEN3
443 Freescale DDR3 controller.
444
York Sun34e026f2014-03-27 17:54:47 -0700445 CONFIG_SYS_FSL_DDRC_GEN4
446 Freescale DDR4 controller.
447
York Sun9ac4ffb2013-09-30 14:20:51 -0700448 CONFIG_SYS_FSL_DDRC_ARM_GEN3
449 Freescale DDR3 controller for ARM-based SoCs.
450
York Sun5614e712013-09-30 09:22:09 -0700451 CONFIG_SYS_FSL_DDR1
452 Board config to use DDR1. It can be enabled for SoCs with
453 Freescale DDR1 or DDR2 controllers, depending on the board
454 implemetation.
455
456 CONFIG_SYS_FSL_DDR2
Robert P. J. Day62a3b7d2016-07-15 13:44:45 -0400457 Board config to use DDR2. It can be enabled for SoCs with
York Sun5614e712013-09-30 09:22:09 -0700458 Freescale DDR2 or DDR3 controllers, depending on the board
459 implementation.
460
461 CONFIG_SYS_FSL_DDR3
462 Board config to use DDR3. It can be enabled for SoCs with
York Sun34e026f2014-03-27 17:54:47 -0700463 Freescale DDR3 or DDR3L controllers.
464
465 CONFIG_SYS_FSL_DDR3L
466 Board config to use DDR3L. It can be enabled for SoCs with
467 DDR3L controllers.
468
469 CONFIG_SYS_FSL_DDR4
470 Board config to use DDR4. It can be enabled for SoCs with
471 DDR4 controllers.
York Sun5614e712013-09-30 09:22:09 -0700472
Prabhakar Kushwaha1b4175d2014-01-18 12:28:30 +0530473 CONFIG_SYS_FSL_IFC_BE
474 Defines the IFC controller register space as Big Endian
475
476 CONFIG_SYS_FSL_IFC_LE
477 Defines the IFC controller register space as Little Endian
478
Prabhakar Kushwaha1c407072017-02-02 15:01:26 +0530479 CONFIG_SYS_FSL_IFC_CLK_DIV
480 Defines divider of platform clock(clock input to IFC controller).
481
Prabhakar Kushwahaadd63f92017-02-02 15:02:00 +0530482 CONFIG_SYS_FSL_LBC_CLK_DIV
483 Defines divider of platform clock(clock input to eLBC controller).
484
Prabhakar Kushwaha690e4252014-01-13 11:28:04 +0530485 CONFIG_SYS_FSL_PBL_PBI
486 It enables addition of RCW (Power on reset configuration) in built image.
487 Please refer doc/README.pblimage for more details
488
489 CONFIG_SYS_FSL_PBL_RCW
490 It adds PBI(pre-boot instructions) commands in u-boot build image.
491 PBI commands can be used to configure SoC before it starts the execution.
492 Please refer doc/README.pblimage for more details
493
York Sun4e5b1bd2014-02-10 13:59:42 -0800494 CONFIG_SYS_FSL_DDR_BE
495 Defines the DDR controller register space as Big Endian
496
497 CONFIG_SYS_FSL_DDR_LE
498 Defines the DDR controller register space as Little Endian
499
York Sun6b9e3092014-02-10 13:59:43 -0800500 CONFIG_SYS_FSL_DDR_SDRAM_BASE_PHY
501 Physical address from the view of DDR controllers. It is the
502 same as CONFIG_SYS_DDR_SDRAM_BASE for all Power SoCs. But
503 it could be different for ARM SoCs.
504
York Sun6b1e1252014-02-10 13:59:44 -0800505 CONFIG_SYS_FSL_DDR_INTLV_256B
506 DDR controller interleaving on 256-byte. This is a special
507 interleaving mode, handled by Dickens for Freescale layerscape
508 SoCs with ARM core.
509
York Sun1d71efb2014-08-01 15:51:00 -0700510 CONFIG_SYS_FSL_DDR_MAIN_NUM_CTRLS
511 Number of controllers used as main memory.
512
513 CONFIG_SYS_FSL_OTHER_DDR_NUM_CTRLS
514 Number of controllers used for other than main memory.
515
Prabhakar Kushwaha44937212015-11-09 16:42:07 +0530516 CONFIG_SYS_FSL_HAS_DP_DDR
517 Defines the SoC has DP-DDR used for DPAA.
518
Ruchika Gupta028dbb82014-09-09 11:50:31 +0530519 CONFIG_SYS_FSL_SEC_BE
520 Defines the SEC controller register space as Big Endian
521
522 CONFIG_SYS_FSL_SEC_LE
523 Defines the SEC controller register space as Little Endian
524
Daniel Schwierzeck92bbd642011-07-27 13:22:39 +0200525- MIPS CPU options:
526 CONFIG_SYS_INIT_SP_OFFSET
527
528 Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack
529 pointer. This is needed for the temporary stack before
530 relocation.
531
Daniel Schwierzeck92bbd642011-07-27 13:22:39 +0200532 CONFIG_XWAY_SWAP_BYTES
533
534 Enable compilation of tools/xway-swap-bytes needed for Lantiq
535 XWAY SoCs for booting from NOR flash. The U-Boot image needs to
536 be swapped if a flash programmer is used.
537
Christian Rieschb67d8812012-02-02 00:44:39 +0000538- ARM options:
539 CONFIG_SYS_EXCEPTION_VECTORS_HIGH
540
541 Select high exception vectors of the ARM core, e.g., do not
542 clear the V bit of the c1 register of CP15.
543
York Sun207774b2015-03-20 19:28:08 -0700544 COUNTER_FREQUENCY
545 Generic timer clock source frequency.
546
547 COUNTER_FREQUENCY_REAL
548 Generic timer clock source frequency if the real clock is
549 different from COUNTER_FREQUENCY, and can only be determined
550 at run time.
551
Stephen Warren73c38932015-01-19 16:25:52 -0700552- Tegra SoC options:
553 CONFIG_TEGRA_SUPPORT_NON_SECURE
554
555 Support executing U-Boot in non-secure (NS) mode. Certain
556 impossible actions will be skipped if the CPU is in NS mode,
557 such as ARM architectural timer initialization.
558
wdenk5da627a2003-10-09 20:09:04 +0000559- Linux Kernel Interface:
wdenk5da627a2003-10-09 20:09:04 +0000560 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
561
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -0800562 When transferring memsize parameter to Linux, some versions
wdenk5da627a2003-10-09 20:09:04 +0000563 expect it to be in bytes, others in MB.
564 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
565
Gerald Van Barenfec6d9e2008-06-03 20:34:45 -0400566 CONFIG_OF_LIBFDT
Wolfgang Denkf57f70a2005-10-13 01:45:54 +0200567
568 New kernel versions are expecting firmware settings to be
Gerald Van Baren213bf8c2007-03-31 12:23:51 -0400569 passed using flattened device trees (based on open firmware
570 concepts).
571
572 CONFIG_OF_LIBFDT
573 * New libfdt-based support
574 * Adds the "fdt" command
Kim Phillips3bb342f2007-08-10 14:34:14 -0500575 * The bootm command automatically updates the fdt
Gerald Van Baren213bf8c2007-03-31 12:23:51 -0400576
Wolfgang Denkf57f70a2005-10-13 01:45:54 +0200577 OF_TBCLK - The timebase frequency.
Kumar Galac2871f02006-01-11 13:59:02 -0600578 OF_STDOUT_PATH - The path to the console device
Wolfgang Denkf57f70a2005-10-13 01:45:54 +0200579
Marcel Ziswiler11ccc332008-07-09 08:17:15 +0200580 boards with QUICC Engines require OF_QE to set UCC MAC
581 addresses
Kim Phillips3bb342f2007-08-10 14:34:14 -0500582
Kumar Gala4e253132006-01-11 13:54:17 -0600583 CONFIG_OF_BOARD_SETUP
584
585 Board code has addition modification that it wants to make
586 to the flat device tree before handing it off to the kernel
wdenk6705d812004-08-02 23:22:59 +0000587
Simon Glassc654b512014-10-23 18:58:54 -0600588 CONFIG_OF_SYSTEM_SETUP
589
590 Other code has addition modification that it wants to make
591 to the flat device tree before handing it off to the kernel.
592 This causes ft_system_setup() to be called before booting
593 the kernel.
594
Heiko Schocher3887c3f2009-09-23 07:56:08 +0200595 CONFIG_OF_IDE_FIXUP
596
597 U-Boot can detect if an IDE device is present or not.
598 If not, and this new config option is activated, U-Boot
599 removes the ATA node from the DTS before booting Linux,
600 so the Linux IDE driver does not probe the device and
601 crash. This is needed for buggy hardware (uc101) where
602 no pull down resistor is connected to the signal IDE5V_DD7.
603
Igor Grinberg7eb29392011-07-14 05:45:07 +0000604 CONFIG_MACH_TYPE [relevant for ARM only][mandatory]
605
606 This setting is mandatory for all boards that have only one
607 machine type and must be used to specify the machine type
608 number as it appears in the ARM machine registry
Naoki Hayama047f6ec2020-10-08 13:17:16 +0900609 (see https://www.arm.linux.org.uk/developer/machines/).
Igor Grinberg7eb29392011-07-14 05:45:07 +0000610 Only boards that have multiple machine types supported
611 in a single configuration file and the machine type is
612 runtime discoverable, do not have to use this setting.
613
Niklaus Giger0b2f4ec2008-11-03 22:13:47 +0100614- vxWorks boot parameters:
615
616 bootvx constructs a valid bootline using the following
Bin Meng9e98b7e2015-10-07 20:19:17 -0700617 environments variables: bootdev, bootfile, ipaddr, netmask,
618 serverip, gatewayip, hostname, othbootargs.
Niklaus Giger0b2f4ec2008-11-03 22:13:47 +0100619 It loads the vxWorks image pointed bootfile.
620
Naoki Hayama81a05d92020-10-08 13:17:08 +0900621 Note: If a "bootargs" environment is defined, it will override
Niklaus Giger0b2f4ec2008-11-03 22:13:47 +0100622 the defaults discussed just above.
623
Aneesh V2c451f72011-06-16 23:30:47 +0000624- Cache Configuration:
Aneesh V2c451f72011-06-16 23:30:47 +0000625 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot
626
Aneesh V93bc2192011-06-16 23:30:51 +0000627- Cache Configuration for ARM:
628 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache
629 controller
630 CONFIG_SYS_PL310_BASE - Physical base address of PL310
631 controller register space
632
wdenk6705d812004-08-02 23:22:59 +0000633- Serial Ports:
Andreas Engel48d01922008-09-08 14:30:53 +0200634 CONFIG_PL010_SERIAL
wdenk6705d812004-08-02 23:22:59 +0000635
636 Define this if you want support for Amba PrimeCell PL010 UARTs.
637
Andreas Engel48d01922008-09-08 14:30:53 +0200638 CONFIG_PL011_SERIAL
wdenk6705d812004-08-02 23:22:59 +0000639
640 Define this if you want support for Amba PrimeCell PL011 UARTs.
641
642 CONFIG_PL011_CLOCK
643
644 If you have Amba PrimeCell PL011 UARTs, set this variable to
645 the clock speed of the UARTs.
646
647 CONFIG_PL01x_PORTS
648
649 If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
650 define this to a list of base addresses for each (supported)
651 port. See e.g. include/configs/versatile.h
652
Karicheri, Muralidharand57dee52014-04-09 15:38:46 -0400653 CONFIG_SERIAL_HW_FLOW_CONTROL
654
655 Define this variable to enable hw flow control in serial driver.
656 Current user of this option is drivers/serial/nsl16550.c driver
wdenk6705d812004-08-02 23:22:59 +0000657
wdenkc6097192002-11-03 00:24:07 +0000658- Autoboot Command:
659 CONFIG_BOOTCOMMAND
660 Only needed when CONFIG_BOOTDELAY is enabled;
661 define a command string that is automatically executed
662 when no character is read on the console interface
663 within "Boot Delay" after reset.
664
wdenkc6097192002-11-03 00:24:07 +0000665 CONFIG_RAMBOOT and CONFIG_NFSBOOT
wdenk43d96162003-03-06 00:02:04 +0000666 The value of these goes into the environment as
667 "ramboot" and "nfsboot" respectively, and can be used
668 as a convenience, when switching between booting from
Marcel Ziswiler11ccc332008-07-09 08:17:15 +0200669 RAM and NFS.
wdenkc6097192002-11-03 00:24:07 +0000670
wdenkc6097192002-11-03 00:24:07 +0000671- Serial Download Echo Mode:
672 CONFIG_LOADS_ECHO
673 If defined to 1, all characters received during a
674 serial download (using the "loads" command) are
675 echoed back. This might be needed by some terminal
676 emulations (like "cu"), but may as well just take
677 time on others. This setting #define's the initial
678 value of the "loads_echo" environment variable.
679
Jon Loeliger602ad3b2007-06-11 19:03:39 -0500680- Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined)
wdenkc6097192002-11-03 00:24:07 +0000681 CONFIG_KGDB_BAUDRATE
682 Select one of the baudrates listed in
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +0200683 CONFIG_SYS_BAUDRATE_TABLE, see below.
wdenkc6097192002-11-03 00:24:07 +0000684
Simon Glass302a6482016-03-13 19:07:28 -0600685- Removal of commands
686 If no commands are needed to boot, you can disable
687 CONFIG_CMDLINE to remove them. In this case, the command line
688 will not be available, and when U-Boot wants to execute the
689 boot command (on start-up) it will call board_run_command()
690 instead. This can reduce image size significantly for very
691 simple boot procedures.
692
Wolfgang Denka5ecbe62013-03-23 23:50:31 +0000693- Regular expression support:
694 CONFIG_REGEX
Wolfgang Denk93e14592013-10-04 17:43:24 +0200695 If this variable is defined, U-Boot is linked against
696 the SLRE (Super Light Regular Expression) library,
697 which adds regex support to some commands, as for
698 example "env grep" and "setexpr".
Wolfgang Denka5ecbe62013-03-23 23:50:31 +0000699
Simon Glass45ba8072011-10-15 05:48:20 +0000700- Device tree:
701 CONFIG_OF_CONTROL
702 If this variable is defined, U-Boot will use a device tree
703 to configure its devices, instead of relying on statically
704 compiled #defines in the board file. This option is
705 experimental and only available on a few boards. The device
706 tree is available in the global data as gd->fdt_blob.
707
Simon Glass2c0f79e2011-10-24 19:15:31 +0000708 U-Boot needs to get its device tree from somewhere. This can
Alex Deymo82f766d2017-04-02 01:25:20 -0700709 be done using one of the three options below:
Simon Glassbbb0b122011-10-15 05:48:21 +0000710
711 CONFIG_OF_EMBED
712 If this variable is defined, U-Boot will embed a device tree
713 binary in its image. This device tree file should be in the
714 board directory and called <soc>-<board>.dts. The binary file
715 is then picked up in board_init_f() and made available through
Nobuhiro Iwamatsueb3eb602017-08-26 07:34:14 +0900716 the global data structure as gd->fdt_blob.
Simon Glass45ba8072011-10-15 05:48:20 +0000717
Simon Glass2c0f79e2011-10-24 19:15:31 +0000718 CONFIG_OF_SEPARATE
719 If this variable is defined, U-Boot will build a device tree
720 binary. It will be called u-boot.dtb. Architecture-specific
721 code will locate it at run-time. Generally this works by:
722
723 cat u-boot.bin u-boot.dtb >image.bin
724
725 and in fact, U-Boot does this for you, creating a file called
726 u-boot-dtb.bin which is useful in the common case. You can
727 still use the individual files if you need something more
728 exotic.
729
Alex Deymo82f766d2017-04-02 01:25:20 -0700730 CONFIG_OF_BOARD
731 If this variable is defined, U-Boot will use the device tree
732 provided by the board at runtime instead of embedding one with
733 the image. Only boards defining board_fdt_blob_setup() support
734 this option (see include/fdtdec.h file).
735
wdenkc6097192002-11-03 00:24:07 +0000736- Watchdog:
737 CONFIG_WATCHDOG
738 If this variable is defined, it enables watchdog
Detlev Zundel6abe6fb2011-04-27 05:25:59 +0000739 support for the SoC. There must be support in the SoC
Christophe Leroy907208c2017-07-06 10:23:22 +0200740 specific code for a watchdog. For the 8xx
741 CPUs, the SIU Watchdog feature is enabled in the SYPCR
742 register. When supported for a specific SoC is
743 available, then no further board specific code should
744 be needed to use it.
Detlev Zundel6abe6fb2011-04-27 05:25:59 +0000745
746 CONFIG_HW_WATCHDOG
747 When using a watchdog circuitry external to the used
748 SoC, then define this variable and provide board
749 specific code for the "hw_watchdog_reset" function.
wdenkc6097192002-11-03 00:24:07 +0000750
751- Real-Time Clock:
752
Jon Loeliger602ad3b2007-06-11 19:03:39 -0500753 When CONFIG_CMD_DATE is selected, the type of the RTC
wdenkc6097192002-11-03 00:24:07 +0000754 has to be selected, too. Define exactly one of the
755 following options:
756
wdenkc6097192002-11-03 00:24:07 +0000757 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
Fabio Estevam4e8b7542011-10-24 06:44:15 +0000758 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC
wdenkc6097192002-11-03 00:24:07 +0000759 CONFIG_RTC_MC146818 - use MC146818 RTC
wdenk1cb8e982003-03-06 21:55:29 +0000760 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
wdenkc6097192002-11-03 00:24:07 +0000761 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
wdenk7f70e852003-05-20 14:25:27 +0000762 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
Markus Niebel412921d2014-07-21 11:06:16 +0200763 CONFIG_RTC_DS1339 - use Maxim, Inc. DS1339 RTC
wdenk3bac3512003-03-12 10:41:04 +0000764 CONFIG_RTC_DS164x - use Dallas DS164x RTC
Tor Krill9536dfc2008-03-15 15:40:26 +0100765 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC
wdenk4c0d4c32004-06-09 17:34:58 +0000766 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
Chris Packham2bd3cab2017-05-30 12:03:33 +1200767 CONFIG_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337
Heiko Schocher71d19f32011-03-28 09:24:22 +0200768 CONFIG_SYS_RV3029_TCR - enable trickle charger on
769 RV3029 RTC.
wdenkc6097192002-11-03 00:24:07 +0000770
wdenkb37c7e52003-06-30 16:24:52 +0000771 Note that if the RTC uses I2C, then the I2C interface
772 must also be configured. See I2C Support, below.
773
Peter Tysere92739d2008-12-17 16:36:21 -0600774- GPIO Support:
775 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO
Peter Tysere92739d2008-12-17 16:36:21 -0600776
Chris Packham5dec49c2010-12-19 10:12:13 +0000777 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of
778 chip-ngpio pairs that tell the PCA953X driver the number of
779 pins supported by a particular chip.
780
Peter Tysere92739d2008-12-17 16:36:21 -0600781 Note that if the GPIO device uses I2C, then the I2C interface
782 must also be configured. See I2C Support, below.
783
Simon Glassaa532332014-06-11 23:29:41 -0600784- I/O tracing:
785 When CONFIG_IO_TRACE is selected, U-Boot intercepts all I/O
786 accesses and can checksum them or write a list of them out
787 to memory. See the 'iotrace' command for details. This is
788 useful for testing device drivers since it can confirm that
789 the driver behaves the same way before and after a code
790 change. Currently this is supported on sandbox and arm. To
791 add support for your architecture, add '#include <iotrace.h>'
792 to the bottom of arch/<arch>/include/asm/io.h and test.
793
794 Example output from the 'iotrace stats' command is below.
795 Note that if the trace buffer is exhausted, the checksum will
796 still continue to operate.
797
798 iotrace is enabled
799 Start: 10000000 (buffer start address)
800 Size: 00010000 (buffer size)
801 Offset: 00000120 (current buffer offset)
802 Output: 10000120 (start + offset)
803 Count: 00000018 (number of trace records)
804 CRC32: 9526fb66 (CRC32 of all trace records)
805
wdenkc6097192002-11-03 00:24:07 +0000806- Timestamp Support:
807
wdenk43d96162003-03-06 00:02:04 +0000808 When CONFIG_TIMESTAMP is selected, the timestamp
809 (date and time) of an image is printed by image
810 commands like bootm or iminfo. This option is
Jon Loeliger602ad3b2007-06-11 19:03:39 -0500811 automatically enabled when you select CONFIG_CMD_DATE .
wdenkc6097192002-11-03 00:24:07 +0000812
Karl O. Pinc923c46f2012-08-16 06:20:15 +0000813- Partition Labels (disklabels) Supported:
814 Zero or more of the following:
815 CONFIG_MAC_PARTITION Apple's MacOS partition table.
Karl O. Pinc923c46f2012-08-16 06:20:15 +0000816 CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc.
817 CONFIG_EFI_PARTITION GPT partition table, common when EFI is the
818 bootloader. Note 2TB partition limit; see
819 disk/part_efi.c
Simon Glassc649e3c2016-05-01 11:36:02 -0600820 CONFIG_SCSI) you must configure support for at
Karl O. Pinc923c46f2012-08-16 06:20:15 +0000821 least one non-MTD partition type as well.
wdenkc6097192002-11-03 00:24:07 +0000822
823- IDE Reset method:
wdenk4d13cba2004-03-14 14:09:05 +0000824 CONFIG_IDE_RESET_ROUTINE - this is defined in several
825 board configurations files but used nowhere!
wdenkc6097192002-11-03 00:24:07 +0000826
wdenk4d13cba2004-03-14 14:09:05 +0000827 CONFIG_IDE_RESET - is this is defined, IDE Reset will
828 be performed by calling the function
829 ide_set_reset(int reset)
830 which has to be defined in a board specific file
wdenkc6097192002-11-03 00:24:07 +0000831
832- ATAPI Support:
833 CONFIG_ATAPI
834
835 Set this to enable ATAPI support.
836
wdenkc40b2952004-03-13 23:29:43 +0000837- LBA48 Support
838 CONFIG_LBA48
839
840 Set this to enable support for disks larger than 137GB
Heiko Schocher4b142fe2009-12-03 11:21:21 +0100841 Also look at CONFIG_SYS_64BIT_LBA.
wdenkc40b2952004-03-13 23:29:43 +0000842 Whithout these , LBA48 support uses 32bit variables and will 'only'
843 support disks up to 2.1TB.
844
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +0200845 CONFIG_SYS_64BIT_LBA:
wdenkc40b2952004-03-13 23:29:43 +0000846 When enabled, makes the IDE subsystem use 64bit sector addresses.
847 Default is 32bit.
848
wdenkc6097192002-11-03 00:24:07 +0000849- SCSI Support:
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +0200850 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and
851 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID *
852 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the
wdenkc6097192002-11-03 00:24:07 +0000853 maximum numbers of LUNs, SCSI ID's and target
854 devices.
wdenkc6097192002-11-03 00:24:07 +0000855
Wolfgang Denk93e14592013-10-04 17:43:24 +0200856 The environment variable 'scsidevs' is set to the number of
857 SCSI devices found during the last scan.
Stefan Reinauer447c0312012-10-29 05:23:48 +0000858
wdenkc6097192002-11-03 00:24:07 +0000859- NETWORK Support (PCI):
wdenk682011f2003-06-03 23:54:09 +0000860 CONFIG_E1000
Kyle Moffettce5207e2011-10-18 11:05:29 +0000861 Support for Intel 8254x/8257x gigabit chips.
862
863 CONFIG_E1000_SPI
864 Utility code for direct access to the SPI bus on Intel 8257x.
865 This does not do anything useful unless you set at least one
866 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC.
867
868 CONFIG_E1000_SPI_GENERIC
869 Allow generic access to the SPI bus on the Intel 8257x, for
870 example with the "sspi" command.
871
wdenkc6097192002-11-03 00:24:07 +0000872 CONFIG_NATSEMI
873 Support for National dp83815 chips.
874
875 CONFIG_NS8382X
876 Support for National dp8382[01] gigabit chips.
877
wdenk45219c42003-05-12 21:50:16 +0000878- NETWORK Support (other):
879
Jens Scharsigc041e9d2010-01-23 12:03:45 +0100880 CONFIG_DRIVER_AT91EMAC
881 Support for AT91RM9200 EMAC.
882
883 CONFIG_RMII
884 Define this to use reduced MII inteface
885
886 CONFIG_DRIVER_AT91EMAC_QUIET
887 If this defined, the driver is quiet.
888 The driver doen't show link status messages.
889
Rob Herringefdd7312011-12-15 11:15:49 +0000890 CONFIG_CALXEDA_XGMAC
891 Support for the Calxeda XGMAC device
892
Ashok3bb46d22012-10-15 06:20:47 +0000893 CONFIG_LAN91C96
wdenk45219c42003-05-12 21:50:16 +0000894 Support for SMSC's LAN91C96 chips.
895
wdenk45219c42003-05-12 21:50:16 +0000896 CONFIG_LAN91C96_USE_32_BIT
897 Define this to enable 32 bit addressing
898
Ashok3bb46d22012-10-15 06:20:47 +0000899 CONFIG_SMC91111
wdenkf39748a2004-06-09 13:37:52 +0000900 Support for SMSC's LAN91C111 chip
901
902 CONFIG_SMC91111_BASE
903 Define this to hold the physical address
904 of the device (I/O space)
905
906 CONFIG_SMC_USE_32_BIT
907 Define this if data bus is 32 bits
908
909 CONFIG_SMC_USE_IOFUNCS
910 Define this to use i/o functions instead of macros
911 (some hardware wont work with macros)
912
Heiko Schocherdc02bad2011-11-15 10:00:04 -0500913 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT
914 Define this if you have more then 3 PHYs.
915
Macpaul Linb3dbf4a52010-12-21 16:59:46 +0800916 CONFIG_FTGMAC100
917 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet
918
919 CONFIG_FTGMAC100_EGIGA
920 Define this to use GE link update with gigabit PHY.
921 Define this if FTGMAC100 is connected to gigabit PHY.
922 If your system has 10/100 PHY only, it might not occur
923 wrong behavior. Because PHY usually return timeout or
924 useless data when polling gigabit status and gigabit
925 control registers. This behavior won't affect the
926 correctnessof 10/100 link speed update.
927
Yoshihiro Shimoda3d0075f2011-01-27 10:06:03 +0900928 CONFIG_SH_ETHER
929 Support for Renesas on-chip Ethernet controller
930
931 CONFIG_SH_ETHER_USE_PORT
932 Define the number of ports to be used
933
934 CONFIG_SH_ETHER_PHY_ADDR
935 Define the ETH PHY's address
936
Yoshihiro Shimoda68260aa2011-01-27 10:06:08 +0900937 CONFIG_SH_ETHER_CACHE_WRITEBACK
938 If this option is set, the driver enables cache flush.
939
Vadim Bendebury5e124722011-10-17 08:36:14 +0000940- TPM Support:
Che-liang Chiou90899cc2013-04-12 11:04:34 +0000941 CONFIG_TPM
942 Support TPM devices.
943
Christophe Ricard0766ad22015-10-06 22:54:41 +0200944 CONFIG_TPM_TIS_INFINEON
945 Support for Infineon i2c bus TPM devices. Only one device
Tom Wai-Hong Tam1b393db2013-04-12 11:04:37 +0000946 per system is supported at this time.
947
Tom Wai-Hong Tam1b393db2013-04-12 11:04:37 +0000948 CONFIG_TPM_TIS_I2C_BURST_LIMITATION
949 Define the burst count bytes upper limit
950
Christophe Ricard3aa74082016-01-21 23:27:13 +0100951 CONFIG_TPM_ST33ZP24
952 Support for STMicroelectronics TPM devices. Requires DM_TPM support.
953
954 CONFIG_TPM_ST33ZP24_I2C
955 Support for STMicroelectronics ST33ZP24 I2C devices.
956 Requires TPM_ST33ZP24 and I2C.
957
Christophe Ricardb75fdc12016-01-21 23:27:14 +0100958 CONFIG_TPM_ST33ZP24_SPI
959 Support for STMicroelectronics ST33ZP24 SPI devices.
960 Requires TPM_ST33ZP24 and SPI.
961
Dirk Eibachc01939c2013-06-26 15:55:15 +0200962 CONFIG_TPM_ATMEL_TWI
963 Support for Atmel TWI TPM device. Requires I2C support.
964
Che-liang Chiou90899cc2013-04-12 11:04:34 +0000965 CONFIG_TPM_TIS_LPC
Vadim Bendebury5e124722011-10-17 08:36:14 +0000966 Support for generic parallel port TPM devices. Only one device
967 per system is supported at this time.
968
969 CONFIG_TPM_TIS_BASE_ADDRESS
970 Base address where the generic TPM device is mapped
971 to. Contemporary x86 systems usually map it at
972 0xfed40000.
973
Reinhard Pfaube6c1522013-06-26 15:55:13 +0200974 CONFIG_TPM
975 Define this to enable the TPM support library which provides
976 functional interfaces to some TPM commands.
977 Requires support for a TPM device.
978
979 CONFIG_TPM_AUTH_SESSIONS
980 Define this to enable authorized functions in the TPM library.
981 Requires CONFIG_TPM and CONFIG_SHA1.
982
wdenkc6097192002-11-03 00:24:07 +0000983- USB Support:
984 At the moment only the UHCI host controller is
Heiko Schocher064b55c2017-06-14 05:49:40 +0200985 supported (PIP405, MIP405); define
wdenkc6097192002-11-03 00:24:07 +0000986 CONFIG_USB_UHCI to enable it.
987 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
wdenk30d56fa2004-10-09 22:44:59 +0000988 and define CONFIG_USB_STORAGE to enable the USB
wdenkc6097192002-11-03 00:24:07 +0000989 storage devices.
990 Note:
991 Supported are USB Keyboards and USB Floppy drives
992 (TEAC FD-05PUB).
wdenk4d13cba2004-03-14 14:09:05 +0000993
Simon Glass9ab4ce22012-02-27 10:52:47 +0000994 CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the
995 txfilltuning field in the EHCI controller on reset.
996
Oleksandr Tymoshenko6e9e0622014-02-01 21:51:25 -0700997 CONFIG_USB_DWC2_REG_ADDR the physical CPU address of the DWC2
998 HW module registers.
999
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +02001000- USB Device:
1001 Define the below if you wish to use the USB console.
1002 Once firmware is rebuilt from a serial console issue the
1003 command "setenv stdin usbtty; setenv stdout usbtty" and
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001004 attach your USB cable. The Unix command "dmesg" should print
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +02001005 it has found a new device. The environment variable usbtty
1006 can be set to gserial or cdc_acm to enable your device to
Wolfgang Denk386eda02006-06-14 18:14:56 +02001007 appear to a USB host as a Linux gserial device or a
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +02001008 Common Device Class Abstract Control Model serial device.
1009 If you select usbtty = gserial you should be able to enumerate
1010 a Linux host by
1011 # modprobe usbserial vendor=0xVendorID product=0xProductID
1012 else if using cdc_acm, simply setting the environment
1013 variable usbtty to be cdc_acm should suffice. The following
1014 might be defined in YourBoardName.h
Wolfgang Denk386eda02006-06-14 18:14:56 +02001015
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +02001016 CONFIG_USB_DEVICE
1017 Define this to build a UDC device
wdenkc6097192002-11-03 00:24:07 +00001018
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +02001019 CONFIG_USB_TTY
1020 Define this to have a tty type of device available to
1021 talk to the UDC device
Wolfgang Denk386eda02006-06-14 18:14:56 +02001022
Vipin KUMARf9da0f82012-03-26 15:38:06 +05301023 CONFIG_USBD_HS
1024 Define this to enable the high speed support for usb
1025 device and usbtty. If this feature is enabled, a routine
1026 int is_usbd_high_speed(void)
1027 also needs to be defined by the driver to dynamically poll
1028 whether the enumeration has succeded at high speed or full
1029 speed.
1030
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001031 CONFIG_SYS_CONSOLE_IS_IN_ENV
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +02001032 Define this if you want stdin, stdout &/or stderr to
1033 be set to usbtty.
1034
Wolfgang Denk386eda02006-06-14 18:14:56 +02001035 If you have a USB-IF assigned VendorID then you may wish to
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +02001036 define your own vendor specific values either in BoardName.h
Wolfgang Denk386eda02006-06-14 18:14:56 +02001037 or directly in usbd_vendor_info.h. If you don't define
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +02001038 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME,
1039 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot
1040 should pretend to be a Linux device to it's target host.
1041
1042 CONFIG_USBD_MANUFACTURER
1043 Define this string as the name of your company for
1044 - CONFIG_USBD_MANUFACTURER "my company"
Wolfgang Denk386eda02006-06-14 18:14:56 +02001045
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +02001046 CONFIG_USBD_PRODUCT_NAME
1047 Define this string as the name of your product
1048 - CONFIG_USBD_PRODUCT_NAME "acme usb device"
1049
1050 CONFIG_USBD_VENDORID
1051 Define this as your assigned Vendor ID from the USB
1052 Implementors Forum. This *must* be a genuine Vendor ID
1053 to avoid polluting the USB namespace.
1054 - CONFIG_USBD_VENDORID 0xFFFF
Wolfgang Denk386eda02006-06-14 18:14:56 +02001055
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +02001056 CONFIG_USBD_PRODUCTID
1057 Define this as the unique Product ID
1058 for your device
1059 - CONFIG_USBD_PRODUCTID 0xFFFF
wdenkc6097192002-11-03 00:24:07 +00001060
Igor Grinbergd70a5602011-12-12 12:08:35 +02001061- ULPI Layer Support:
1062 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via
1063 the generic ULPI layer. The generic layer accesses the ULPI PHY
1064 via the platform viewport, so you need both the genric layer and
1065 the viewport enabled. Currently only Chipidea/ARC based
1066 viewport is supported.
1067 To enable the ULPI layer support, define CONFIG_USB_ULPI and
1068 CONFIG_USB_ULPI_VIEWPORT in your board configuration file.
Lucas Stach6d365ea2012-10-01 00:44:35 +02001069 If your ULPI phy needs a different reference clock than the
1070 standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to
1071 the appropriate value in Hz.
wdenkc6097192002-11-03 00:24:07 +00001072
1073- MMC Support:
1074 The MMC controller on the Intel PXA is supported. To
1075 enable this define CONFIG_MMC. The MMC can be
1076 accessed from the boot prompt by mapping the device
1077 to physical memory similar to flash. Command line is
Jon Loeliger602ad3b2007-06-11 19:03:39 -05001078 enabled with CONFIG_CMD_MMC. The MMC driver also works with
1079 the FAT fs. This is enabled with CONFIG_CMD_FAT.
wdenkc6097192002-11-03 00:24:07 +00001080
Yoshihiro Shimodaafb35662011-07-04 22:21:22 +00001081 CONFIG_SH_MMCIF
1082 Support for Renesas on-chip MMCIF controller
1083
1084 CONFIG_SH_MMCIF_ADDR
1085 Define the base address of MMCIF registers
1086
1087 CONFIG_SH_MMCIF_CLK
1088 Define the clock frequency for MMCIF
1089
Tom Rinib3ba6e92013-03-14 05:32:47 +00001090- USB Device Firmware Update (DFU) class support:
Marek Vasutbb4059a2018-02-16 16:41:18 +01001091 CONFIG_DFU_OVER_USB
Tom Rinib3ba6e92013-03-14 05:32:47 +00001092 This enables the USB portion of the DFU USB class
1093
Pantelis Antoniouc6631762013-03-14 05:32:52 +00001094 CONFIG_DFU_NAND
1095 This enables support for exposing NAND devices via DFU.
1096
Afzal Mohammeda9479f02013-09-18 01:15:24 +05301097 CONFIG_DFU_RAM
1098 This enables support for exposing RAM via DFU.
1099 Note: DFU spec refer to non-volatile memory usage, but
1100 allow usages beyond the scope of spec - here RAM usage,
1101 one that would help mostly the developer.
1102
Heiko Schochere7e75c72013-06-12 06:05:51 +02001103 CONFIG_SYS_DFU_DATA_BUF_SIZE
1104 Dfu transfer uses a buffer before writing data to the
1105 raw storage device. Make the size (in bytes) of this buffer
1106 configurable. The size of this buffer is also configurable
1107 through the "dfu_bufsiz" environment variable.
1108
Pantelis Antoniouea2453d2013-03-14 05:32:48 +00001109 CONFIG_SYS_DFU_MAX_FILE_SIZE
1110 When updating files rather than the raw storage device,
1111 we use a static buffer to copy the file into and then write
1112 the buffer once we've been given the whole file. Define
1113 this to the maximum filesize (in bytes) for the buffer.
1114 Default is 4 MiB if undefined.
1115
Heiko Schocher001a8312014-03-18 08:09:56 +01001116 DFU_DEFAULT_POLL_TIMEOUT
1117 Poll timeout [ms], is the timeout a device can send to the
1118 host. The host must wait for this timeout before sending
1119 a subsequent DFU_GET_STATUS request to the device.
1120
1121 DFU_MANIFEST_POLL_TIMEOUT
1122 Poll timeout [ms], which the device sends to the host when
1123 entering dfuMANIFEST state. Host waits this timeout, before
1124 sending again an USB request to the device.
1125
wdenk6705d812004-08-02 23:22:59 +00001126- Journaling Flash filesystem support:
Simon Glassb2482df2016-10-02 18:00:59 -06001127 CONFIG_JFFS2_NAND
wdenk6705d812004-08-02 23:22:59 +00001128 Define these for a default partition on a NAND device
1129
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001130 CONFIG_SYS_JFFS2_FIRST_SECTOR,
1131 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS
wdenk6705d812004-08-02 23:22:59 +00001132 Define these for a default partition on a NOR device
1133
wdenkc6097192002-11-03 00:24:07 +00001134- Keyboard Support:
Simon Glass39f615e2015-11-11 10:05:47 -07001135 See Kconfig help for available keyboard drivers.
1136
1137 CONFIG_KEYBOARD
1138
1139 Define this to enable a custom keyboard support.
1140 This simply calls drv_keyboard_init() which must be
1141 defined in your board-specific files. This option is deprecated
1142 and is only used by novena. For new boards, use driver model
1143 instead.
wdenkc6097192002-11-03 00:24:07 +00001144
1145- Video support:
Timur Tabi7d3053f2011-02-15 17:09:19 -06001146 CONFIG_FSL_DIU_FB
Wolfgang Denk04e5ae72011-09-11 21:24:09 +02001147 Enable the Freescale DIU video driver. Reference boards for
Timur Tabi7d3053f2011-02-15 17:09:19 -06001148 SOCs that have a DIU should define this macro to enable DIU
1149 support, and should also define these other macros:
1150
1151 CONFIG_SYS_DIU_ADDR
1152 CONFIG_VIDEO
Timur Tabi7d3053f2011-02-15 17:09:19 -06001153 CONFIG_CFB_CONSOLE
1154 CONFIG_VIDEO_SW_CURSOR
1155 CONFIG_VGA_AS_SINGLE_DEVICE
1156 CONFIG_VIDEO_LOGO
1157 CONFIG_VIDEO_BMP_LOGO
1158
Timur Tabiba8e76b2011-04-11 14:18:22 -05001159 The DIU driver will look for the 'video-mode' environment
1160 variable, and if defined, enable the DIU as a console during
Fabio Estevam8eca9432016-04-02 11:53:18 -03001161 boot. See the documentation file doc/README.video for a
Timur Tabiba8e76b2011-04-11 14:18:22 -05001162 description of this variable.
Timur Tabi7d3053f2011-02-15 17:09:19 -06001163
wdenkc6097192002-11-03 00:24:07 +00001164- LCD Support: CONFIG_LCD
1165
1166 Define this to enable LCD support (for output to LCD
1167 display); also select one of the supported displays
1168 by defining one of these:
1169
Stelian Pop39cf4802008-05-09 21:57:18 +02001170 CONFIG_ATMEL_LCD:
1171
1172 HITACHI TX09D70VM1CCA, 3.5", 240x320.
1173
wdenkfd3103b2003-11-25 16:55:19 +00001174 CONFIG_NEC_NL6448AC33:
wdenkc6097192002-11-03 00:24:07 +00001175
wdenkfd3103b2003-11-25 16:55:19 +00001176 NEC NL6448AC33-18. Active, color, single scan.
wdenkc6097192002-11-03 00:24:07 +00001177
wdenkfd3103b2003-11-25 16:55:19 +00001178 CONFIG_NEC_NL6448BC20
wdenkc6097192002-11-03 00:24:07 +00001179
wdenkfd3103b2003-11-25 16:55:19 +00001180 NEC NL6448BC20-08. 6.5", 640x480.
1181 Active, color, single scan.
1182
1183 CONFIG_NEC_NL6448BC33_54
1184
1185 NEC NL6448BC33-54. 10.4", 640x480.
wdenkc6097192002-11-03 00:24:07 +00001186 Active, color, single scan.
1187
1188 CONFIG_SHARP_16x9
1189
1190 Sharp 320x240. Active, color, single scan.
1191 It isn't 16x9, and I am not sure what it is.
1192
1193 CONFIG_SHARP_LQ64D341
1194
1195 Sharp LQ64D341 display, 640x480.
1196 Active, color, single scan.
1197
1198 CONFIG_HLD1045
1199
1200 HLD1045 display, 640x480.
1201 Active, color, single scan.
1202
1203 CONFIG_OPTREX_BW
1204
1205 Optrex CBL50840-2 NF-FW 99 22 M5
1206 or
1207 Hitachi LMG6912RPFC-00T
1208 or
1209 Hitachi SP14Q002
1210
1211 320x240. Black & white.
1212
Simon Glass676d3192012-10-17 13:24:54 +00001213 CONFIG_LCD_ALIGNMENT
1214
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08001215 Normally the LCD is page-aligned (typically 4KB). If this is
Simon Glass676d3192012-10-17 13:24:54 +00001216 defined then the LCD will be aligned to this value instead.
1217 For ARM it is sometimes useful to use MMU_SECTION_SIZE
1218 here, since it is cheaper to change data cache settings on
1219 a per-section basis.
1220
1221
Hannes Petermaier604c7d42015-03-27 08:01:38 +01001222 CONFIG_LCD_ROTATION
1223
1224 Sometimes, for example if the display is mounted in portrait
1225 mode or even if it's mounted landscape but rotated by 180degree,
1226 we need to rotate our content of the display relative to the
1227 framebuffer, so that user can read the messages which are
1228 printed out.
1229 Once CONFIG_LCD_ROTATION is defined, the lcd_console will be
1230 initialized with a given rotation from "vl_rot" out of
1231 "vidinfo_t" which is provided by the board specific code.
1232 The value for vl_rot is coded as following (matching to
1233 fbcon=rotate:<n> linux-kernel commandline):
1234 0 = no rotation respectively 0 degree
1235 1 = 90 degree rotation
1236 2 = 180 degree rotation
1237 3 = 270 degree rotation
1238
1239 If CONFIG_LCD_ROTATION is not defined, the console will be
1240 initialized with 0degree rotation.
1241
Tom Wai-Hong Tam45d7f522012-09-28 15:11:16 +00001242 CONFIG_LCD_BMP_RLE8
1243
1244 Support drawing of RLE8-compressed bitmaps on the LCD.
1245
Tom Wai-Hong Tam735987c2012-12-05 14:46:40 +00001246 CONFIG_I2C_EDID
1247
1248 Enables an 'i2c edid' command which can read EDID
1249 information over I2C from an attached LCD display.
1250
wdenk17ea1172004-06-06 21:51:03 +00001251- MII/PHY support:
wdenk17ea1172004-06-06 21:51:03 +00001252 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
1253
1254 The clock frequency of the MII bus
1255
wdenk17ea1172004-06-06 21:51:03 +00001256 CONFIG_PHY_RESET_DELAY
1257
1258 Some PHY like Intel LXT971A need extra delay after
1259 reset before any MII register access is possible.
1260 For such PHY, set this option to the usec delay
1261 required. (minimum 300usec for LXT971A)
1262
1263 CONFIG_PHY_CMD_DELAY (ppc4xx)
1264
1265 Some PHY like Intel LXT971A need extra delay after
1266 command issued before MII status register can be read
1267
wdenkc6097192002-11-03 00:24:07 +00001268- IP address:
1269 CONFIG_IPADDR
1270
1271 Define a default value for the IP address to use for
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001272 the default Ethernet interface, in case this is not
wdenkc6097192002-11-03 00:24:07 +00001273 determined through e.g. bootp.
Wolfgang Denk1ebcd652011-10-26 10:21:22 +00001274 (Environment variable "ipaddr")
wdenkc6097192002-11-03 00:24:07 +00001275
1276- Server IP address:
1277 CONFIG_SERVERIP
1278
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001279 Defines a default value for the IP address of a TFTP
wdenkc6097192002-11-03 00:24:07 +00001280 server to contact when using the "tftboot" command.
Wolfgang Denk1ebcd652011-10-26 10:21:22 +00001281 (Environment variable "serverip")
wdenkc6097192002-11-03 00:24:07 +00001282
Robin Getz97cfe862009-07-21 12:15:28 -04001283 CONFIG_KEEP_SERVERADDR
1284
1285 Keeps the server's MAC address, in the env 'serveraddr'
1286 for passing to bootargs (like Linux's netconsole option)
1287
Wolfgang Denk1ebcd652011-10-26 10:21:22 +00001288- Gateway IP address:
1289 CONFIG_GATEWAYIP
1290
1291 Defines a default value for the IP address of the
1292 default router where packets to other networks are
1293 sent to.
1294 (Environment variable "gatewayip")
1295
1296- Subnet mask:
1297 CONFIG_NETMASK
1298
1299 Defines a default value for the subnet mask (or
1300 routing prefix) which is used to determine if an IP
1301 address belongs to the local subnet or needs to be
1302 forwarded through a router.
1303 (Environment variable "netmask")
1304
wdenkc6097192002-11-03 00:24:07 +00001305- BOOTP Recovery Mode:
1306 CONFIG_BOOTP_RANDOM_DELAY
1307
1308 If you have many targets in a network that try to
1309 boot using BOOTP, you may want to avoid that all
1310 systems send out BOOTP requests at precisely the same
1311 moment (which would happen for instance at recovery
1312 from a power failure, when all systems will try to
1313 boot, thus flooding the BOOTP server. Defining
1314 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
1315 inserted before sending out BOOTP requests. The
Wolfgang Denk6c33c782007-08-06 23:21:05 +02001316 following delays are inserted then:
wdenkc6097192002-11-03 00:24:07 +00001317
1318 1st BOOTP request: delay 0 ... 1 sec
1319 2nd BOOTP request: delay 0 ... 2 sec
1320 3rd BOOTP request: delay 0 ... 4 sec
1321 4th and following
1322 BOOTP requests: delay 0 ... 8 sec
1323
Thierry Reding92ac8ac2014-08-19 10:21:24 +02001324 CONFIG_BOOTP_ID_CACHE_SIZE
1325
1326 BOOTP packets are uniquely identified using a 32-bit ID. The
1327 server will copy the ID from client requests to responses and
1328 U-Boot will use this to determine if it is the destination of
1329 an incoming response. Some servers will check that addresses
1330 aren't in use before handing them out (usually using an ARP
1331 ping) and therefore take up to a few hundred milliseconds to
1332 respond. Network congestion may also influence the time it
1333 takes for a response to make it back to the client. If that
1334 time is too long, U-Boot will retransmit requests. In order
1335 to allow earlier responses to still be accepted after these
1336 retransmissions, U-Boot's BOOTP client keeps a small cache of
1337 IDs. The CONFIG_BOOTP_ID_CACHE_SIZE controls the size of this
1338 cache. The default is to keep IDs for up to four outstanding
1339 requests. Increasing this will allow U-Boot to accept offers
1340 from a BOOTP client in networks with unusually high latency.
1341
stroesefe389a82003-08-28 14:17:32 +00001342- DHCP Advanced Options:
Jon Loeliger1fe80d72007-07-09 22:08:34 -05001343 You can fine tune the DHCP functionality by defining
1344 CONFIG_BOOTP_* symbols:
stroesefe389a82003-08-28 14:17:32 +00001345
Jon Loeliger1fe80d72007-07-09 22:08:34 -05001346 CONFIG_BOOTP_NISDOMAIN
Jon Loeliger1fe80d72007-07-09 22:08:34 -05001347 CONFIG_BOOTP_BOOTFILESIZE
Jon Loeliger1fe80d72007-07-09 22:08:34 -05001348 CONFIG_BOOTP_NTPSERVER
1349 CONFIG_BOOTP_TIMEOFFSET
1350 CONFIG_BOOTP_VENDOREX
Joe Hershberger2c00e092012-05-23 07:59:19 +00001351 CONFIG_BOOTP_MAY_FAIL
stroesefe389a82003-08-28 14:17:32 +00001352
Wilson Callan5d110f02007-07-28 10:56:13 -04001353 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip
1354 environment variable, not the BOOTP server.
stroesefe389a82003-08-28 14:17:32 +00001355
Joe Hershberger2c00e092012-05-23 07:59:19 +00001356 CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found
1357 after the configured retry count, the call will fail
1358 instead of starting over. This can be used to fail over
1359 to Link-local IP address configuration if the DHCP server
1360 is not available.
1361
Aras Vaichasd9a2f412008-03-26 09:43:57 +11001362 CONFIG_BOOTP_DHCP_REQUEST_DELAY
1363
1364 A 32bit value in microseconds for a delay between
1365 receiving a "DHCP Offer" and sending the "DHCP Request".
1366 This fixes a problem with certain DHCP servers that don't
1367 respond 100% of the time to a "DHCP request". E.g. On an
1368 AT91RM9200 processor running at 180MHz, this delay needed
1369 to be *at least* 15,000 usec before a Windows Server 2003
1370 DHCP server would reply 100% of the time. I recommend at
1371 least 50,000 usec to be safe. The alternative is to hope
1372 that one of the retries will be successful but note that
1373 the DHCP timeout and retry process takes a longer than
1374 this delay.
1375
Joe Hershbergerd22c3382012-05-23 08:00:12 +00001376 - Link-local IP address negotiation:
1377 Negotiate with other link-local clients on the local network
1378 for an address that doesn't require explicit configuration.
1379 This is especially useful if a DHCP server cannot be guaranteed
1380 to exist in all environments that the device must operate.
1381
1382 See doc/README.link-local for more information.
1383
Prabhakar Kushwaha24acb832017-11-23 16:51:32 +05301384 - MAC address from environment variables
1385
1386 FDT_SEQ_MACADDR_FROM_ENV
1387
1388 Fix-up device tree with MAC addresses fetched sequentially from
1389 environment variables. This config work on assumption that
1390 non-usable ethernet node of device-tree are either not present
1391 or their status has been marked as "disabled".
1392
wdenka3d991b2004-04-15 21:48:45 +00001393 - CDP Options:
wdenk6e592382004-04-18 17:39:38 +00001394 CONFIG_CDP_DEVICE_ID
wdenka3d991b2004-04-15 21:48:45 +00001395
1396 The device id used in CDP trigger frames.
1397
1398 CONFIG_CDP_DEVICE_ID_PREFIX
1399
1400 A two character string which is prefixed to the MAC address
1401 of the device.
1402
1403 CONFIG_CDP_PORT_ID
1404
1405 A printf format string which contains the ascii name of
1406 the port. Normally is set to "eth%d" which sets
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001407 eth0 for the first Ethernet, eth1 for the second etc.
wdenka3d991b2004-04-15 21:48:45 +00001408
1409 CONFIG_CDP_CAPABILITIES
1410
1411 A 32bit integer which indicates the device capabilities;
1412 0x00000010 for a normal host which does not forwards.
1413
1414 CONFIG_CDP_VERSION
1415
1416 An ascii string containing the version of the software.
1417
1418 CONFIG_CDP_PLATFORM
1419
1420 An ascii string containing the name of the platform.
1421
1422 CONFIG_CDP_TRIGGER
1423
1424 A 32bit integer sent on the trigger.
1425
1426 CONFIG_CDP_POWER_CONSUMPTION
1427
1428 A 16bit integer containing the power consumption of the
1429 device in .1 of milliwatts.
1430
1431 CONFIG_CDP_APPLIANCE_VLAN_TYPE
1432
1433 A byte containing the id of the VLAN.
1434
Uri Mashiach79267ed2017-01-19 10:51:05 +02001435- Status LED: CONFIG_LED_STATUS
wdenkc6097192002-11-03 00:24:07 +00001436
1437 Several configurations allow to display the current
1438 status using a LED. For instance, the LED will blink
1439 fast while running U-Boot code, stop blinking as
1440 soon as a reply to a BOOTP request was received, and
1441 start blinking slow once the Linux kernel is running
1442 (supported by a status LED driver in the Linux
Uri Mashiach79267ed2017-01-19 10:51:05 +02001443 kernel). Defining CONFIG_LED_STATUS enables this
wdenkc6097192002-11-03 00:24:07 +00001444 feature in U-Boot.
1445
Igor Grinberg1df7bbb2013-11-08 01:03:50 +02001446 Additional options:
1447
Uri Mashiach79267ed2017-01-19 10:51:05 +02001448 CONFIG_LED_STATUS_GPIO
Igor Grinberg1df7bbb2013-11-08 01:03:50 +02001449 The status LED can be connected to a GPIO pin.
1450 In such cases, the gpio_led driver can be used as a
Uri Mashiach79267ed2017-01-19 10:51:05 +02001451 status LED backend implementation. Define CONFIG_LED_STATUS_GPIO
Igor Grinberg1df7bbb2013-11-08 01:03:50 +02001452 to include the gpio_led driver in the U-Boot binary.
1453
Igor Grinberg9dfdcdf2013-11-08 01:03:52 +02001454 CONFIG_GPIO_LED_INVERTED_TABLE
1455 Some GPIO connected LEDs may have inverted polarity in which
1456 case the GPIO high value corresponds to LED off state and
1457 GPIO low value corresponds to LED on state.
1458 In such cases CONFIG_GPIO_LED_INVERTED_TABLE may be defined
1459 with a list of GPIO LEDs that have inverted polarity.
1460
Heiko Schocher3f4978c2012-01-16 21:12:24 +00001461- I2C Support: CONFIG_SYS_I2C
wdenkc6097192002-11-03 00:24:07 +00001462
Heiko Schocher3f4978c2012-01-16 21:12:24 +00001463 This enable the NEW i2c subsystem, and will allow you to use
1464 i2c commands at the u-boot command line (as long as you set
Heiko Schocherea818db2013-01-29 08:53:15 +01001465 CONFIG_SYS_I2C_SOFT_SPEED and CONFIG_SYS_I2C_SOFT_SLAVE
1466 for defining speed and slave address
1467 - activate second bus with I2C_SOFT_DECLARATIONS2 define
1468 CONFIG_SYS_I2C_SOFT_SPEED_2 and CONFIG_SYS_I2C_SOFT_SLAVE_2
1469 for defining speed and slave address
1470 - activate third bus with I2C_SOFT_DECLARATIONS3 define
1471 CONFIG_SYS_I2C_SOFT_SPEED_3 and CONFIG_SYS_I2C_SOFT_SLAVE_3
1472 for defining speed and slave address
1473 - activate fourth bus with I2C_SOFT_DECLARATIONS4 define
1474 CONFIG_SYS_I2C_SOFT_SPEED_4 and CONFIG_SYS_I2C_SOFT_SLAVE_4
1475 for defining speed and slave address
Heiko Schocher3f4978c2012-01-16 21:12:24 +00001476
Heiko Schocher00f792e2012-10-24 13:48:22 +02001477 - drivers/i2c/fsl_i2c.c:
1478 - activate i2c driver with CONFIG_SYS_I2C_FSL
1479 define CONFIG_SYS_FSL_I2C_OFFSET for setting the register
1480 offset CONFIG_SYS_FSL_I2C_SPEED for the i2c speed and
1481 CONFIG_SYS_FSL_I2C_SLAVE for the slave addr of the first
1482 bus.
Wolfgang Denk93e14592013-10-04 17:43:24 +02001483 - If your board supports a second fsl i2c bus, define
Heiko Schocher00f792e2012-10-24 13:48:22 +02001484 CONFIG_SYS_FSL_I2C2_OFFSET for the register offset
1485 CONFIG_SYS_FSL_I2C2_SPEED for the speed and
1486 CONFIG_SYS_FSL_I2C2_SLAVE for the slave address of the
1487 second bus.
1488
Simon Glass1f2ba722012-10-30 07:28:53 +00001489 - drivers/i2c/tegra_i2c.c:
Nobuhiro Iwamatsu10cee512013-10-11 16:23:53 +09001490 - activate this driver with CONFIG_SYS_I2C_TEGRA
1491 - This driver adds 4 i2c buses with a fix speed from
1492 100000 and the slave addr 0!
Simon Glass1f2ba722012-10-30 07:28:53 +00001493
Dirk Eibach880540d2013-04-25 02:40:01 +00001494 - drivers/i2c/ppc4xx_i2c.c
1495 - activate this driver with CONFIG_SYS_I2C_PPC4XX
1496 - CONFIG_SYS_I2C_PPC4XX_CH0 activate hardware channel 0
1497 - CONFIG_SYS_I2C_PPC4XX_CH1 activate hardware channel 1
1498
tremfac96402013-09-21 18:13:35 +02001499 - drivers/i2c/i2c_mxc.c
1500 - activate this driver with CONFIG_SYS_I2C_MXC
Albert ARIBAUD \\(3ADEV\\)03544c62015-09-21 22:43:38 +02001501 - enable bus 1 with CONFIG_SYS_I2C_MXC_I2C1
1502 - enable bus 2 with CONFIG_SYS_I2C_MXC_I2C2
1503 - enable bus 3 with CONFIG_SYS_I2C_MXC_I2C3
1504 - enable bus 4 with CONFIG_SYS_I2C_MXC_I2C4
tremfac96402013-09-21 18:13:35 +02001505 - define speed for bus 1 with CONFIG_SYS_MXC_I2C1_SPEED
1506 - define slave for bus 1 with CONFIG_SYS_MXC_I2C1_SLAVE
1507 - define speed for bus 2 with CONFIG_SYS_MXC_I2C2_SPEED
1508 - define slave for bus 2 with CONFIG_SYS_MXC_I2C2_SLAVE
1509 - define speed for bus 3 with CONFIG_SYS_MXC_I2C3_SPEED
1510 - define slave for bus 3 with CONFIG_SYS_MXC_I2C3_SLAVE
Albert ARIBAUD \\(3ADEV\\)03544c62015-09-21 22:43:38 +02001511 - define speed for bus 4 with CONFIG_SYS_MXC_I2C4_SPEED
1512 - define slave for bus 4 with CONFIG_SYS_MXC_I2C4_SLAVE
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08001513 If those defines are not set, default value is 100000
tremfac96402013-09-21 18:13:35 +02001514 for speed, and 0 for slave.
1515
Nobuhiro Iwamatsu1086bfa2013-09-27 16:58:30 +09001516 - drivers/i2c/rcar_i2c.c:
1517 - activate this driver with CONFIG_SYS_I2C_RCAR
1518 - This driver adds 4 i2c buses
1519
Nobuhiro Iwamatsu2035d772013-10-29 13:33:51 +09001520 - drivers/i2c/sh_i2c.c:
1521 - activate this driver with CONFIG_SYS_I2C_SH
1522 - This driver adds from 2 to 5 i2c buses
1523
1524 - CONFIG_SYS_I2C_SH_BASE0 for setting the register channel 0
1525 - CONFIG_SYS_I2C_SH_SPEED0 for for the speed channel 0
1526 - CONFIG_SYS_I2C_SH_BASE1 for setting the register channel 1
1527 - CONFIG_SYS_I2C_SH_SPEED1 for for the speed channel 1
1528 - CONFIG_SYS_I2C_SH_BASE2 for setting the register channel 2
1529 - CONFIG_SYS_I2C_SH_SPEED2 for for the speed channel 2
1530 - CONFIG_SYS_I2C_SH_BASE3 for setting the register channel 3
1531 - CONFIG_SYS_I2C_SH_SPEED3 for for the speed channel 3
1532 - CONFIG_SYS_I2C_SH_BASE4 for setting the register channel 4
1533 - CONFIG_SYS_I2C_SH_SPEED4 for for the speed channel 4
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08001534 - CONFIG_SYS_I2C_SH_NUM_CONTROLLERS for number of i2c buses
Nobuhiro Iwamatsu2035d772013-10-29 13:33:51 +09001535
Heiko Schocher6789e842013-10-22 11:03:18 +02001536 - drivers/i2c/omap24xx_i2c.c
1537 - activate this driver with CONFIG_SYS_I2C_OMAP24XX
1538 - CONFIG_SYS_OMAP24_I2C_SPEED speed channel 0
1539 - CONFIG_SYS_OMAP24_I2C_SLAVE slave addr channel 0
1540 - CONFIG_SYS_OMAP24_I2C_SPEED1 speed channel 1
1541 - CONFIG_SYS_OMAP24_I2C_SLAVE1 slave addr channel 1
1542 - CONFIG_SYS_OMAP24_I2C_SPEED2 speed channel 2
1543 - CONFIG_SYS_OMAP24_I2C_SLAVE2 slave addr channel 2
1544 - CONFIG_SYS_OMAP24_I2C_SPEED3 speed channel 3
1545 - CONFIG_SYS_OMAP24_I2C_SLAVE3 slave addr channel 3
1546 - CONFIG_SYS_OMAP24_I2C_SPEED4 speed channel 4
1547 - CONFIG_SYS_OMAP24_I2C_SLAVE4 slave addr channel 4
1548
Naveen Krishna Che717fc62013-12-06 12:12:38 +05301549 - drivers/i2c/s3c24x0_i2c.c:
1550 - activate this driver with CONFIG_SYS_I2C_S3C24X0
1551 - This driver adds i2c buses (11 for Exynos5250, Exynos5420
1552 9 i2c buses for Exynos4 and 1 for S3C24X0 SoCs from Samsung)
1553 with a fix speed from 100000 and the slave addr 0!
1554
Dirk Eibachb46226b2014-07-03 09:28:18 +02001555 - drivers/i2c/ihs_i2c.c
1556 - activate this driver with CONFIG_SYS_I2C_IHS
1557 - CONFIG_SYS_I2C_IHS_CH0 activate hardware channel 0
1558 - CONFIG_SYS_I2C_IHS_SPEED_0 speed channel 0
1559 - CONFIG_SYS_I2C_IHS_SLAVE_0 slave addr channel 0
1560 - CONFIG_SYS_I2C_IHS_CH1 activate hardware channel 1
1561 - CONFIG_SYS_I2C_IHS_SPEED_1 speed channel 1
1562 - CONFIG_SYS_I2C_IHS_SLAVE_1 slave addr channel 1
1563 - CONFIG_SYS_I2C_IHS_CH2 activate hardware channel 2
1564 - CONFIG_SYS_I2C_IHS_SPEED_2 speed channel 2
1565 - CONFIG_SYS_I2C_IHS_SLAVE_2 slave addr channel 2
1566 - CONFIG_SYS_I2C_IHS_CH3 activate hardware channel 3
1567 - CONFIG_SYS_I2C_IHS_SPEED_3 speed channel 3
1568 - CONFIG_SYS_I2C_IHS_SLAVE_3 slave addr channel 3
Dirk Eibach071be892015-10-28 11:46:22 +01001569 - activate dual channel with CONFIG_SYS_I2C_IHS_DUAL
1570 - CONFIG_SYS_I2C_IHS_SPEED_0_1 speed channel 0_1
1571 - CONFIG_SYS_I2C_IHS_SLAVE_0_1 slave addr channel 0_1
1572 - CONFIG_SYS_I2C_IHS_SPEED_1_1 speed channel 1_1
1573 - CONFIG_SYS_I2C_IHS_SLAVE_1_1 slave addr channel 1_1
1574 - CONFIG_SYS_I2C_IHS_SPEED_2_1 speed channel 2_1
1575 - CONFIG_SYS_I2C_IHS_SLAVE_2_1 slave addr channel 2_1
1576 - CONFIG_SYS_I2C_IHS_SPEED_3_1 speed channel 3_1
1577 - CONFIG_SYS_I2C_IHS_SLAVE_3_1 slave addr channel 3_1
Dirk Eibachb46226b2014-07-03 09:28:18 +02001578
Heiko Schocher3f4978c2012-01-16 21:12:24 +00001579 additional defines:
1580
1581 CONFIG_SYS_NUM_I2C_BUSES
Simon Glass945a18e2016-10-02 18:01:05 -06001582 Hold the number of i2c buses you want to use.
Heiko Schocher3f4978c2012-01-16 21:12:24 +00001583
1584 CONFIG_SYS_I2C_DIRECT_BUS
1585 define this, if you don't use i2c muxes on your hardware.
1586 if CONFIG_SYS_I2C_MAX_HOPS is not defined or == 0 you can
1587 omit this define.
1588
1589 CONFIG_SYS_I2C_MAX_HOPS
1590 define how many muxes are maximal consecutively connected
1591 on one i2c bus. If you not use i2c muxes, omit this
1592 define.
1593
1594 CONFIG_SYS_I2C_BUSES
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08001595 hold a list of buses you want to use, only used if
Heiko Schocher3f4978c2012-01-16 21:12:24 +00001596 CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example
1597 a board with CONFIG_SYS_I2C_MAX_HOPS = 1 and
1598 CONFIG_SYS_NUM_I2C_BUSES = 9:
1599
1600 CONFIG_SYS_I2C_BUSES {{0, {I2C_NULL_HOP}}, \
1601 {0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \
1602 {0, {{I2C_MUX_PCA9547, 0x70, 2}}}, \
1603 {0, {{I2C_MUX_PCA9547, 0x70, 3}}}, \
1604 {0, {{I2C_MUX_PCA9547, 0x70, 4}}}, \
1605 {0, {{I2C_MUX_PCA9547, 0x70, 5}}}, \
1606 {1, {I2C_NULL_HOP}}, \
1607 {1, {{I2C_MUX_PCA9544, 0x72, 1}}}, \
1608 {1, {{I2C_MUX_PCA9544, 0x72, 2}}}, \
1609 }
1610
1611 which defines
1612 bus 0 on adapter 0 without a mux
Heiko Schocherea818db2013-01-29 08:53:15 +01001613 bus 1 on adapter 0 with a PCA9547 on address 0x70 port 1
1614 bus 2 on adapter 0 with a PCA9547 on address 0x70 port 2
1615 bus 3 on adapter 0 with a PCA9547 on address 0x70 port 3
1616 bus 4 on adapter 0 with a PCA9547 on address 0x70 port 4
1617 bus 5 on adapter 0 with a PCA9547 on address 0x70 port 5
Heiko Schocher3f4978c2012-01-16 21:12:24 +00001618 bus 6 on adapter 1 without a mux
Heiko Schocherea818db2013-01-29 08:53:15 +01001619 bus 7 on adapter 1 with a PCA9544 on address 0x72 port 1
1620 bus 8 on adapter 1 with a PCA9544 on address 0x72 port 2
Heiko Schocher3f4978c2012-01-16 21:12:24 +00001621
1622 If you do not have i2c muxes on your board, omit this define.
1623
Simon Glassce3b5d62017-05-12 21:10:00 -06001624- Legacy I2C Support:
Heiko Schocherea818db2013-01-29 08:53:15 +01001625 If you use the software i2c interface (CONFIG_SYS_I2C_SOFT)
wdenkb37c7e52003-06-30 16:24:52 +00001626 then the following macros need to be defined (examples are
1627 from include/configs/lwmon.h):
wdenkc6097192002-11-03 00:24:07 +00001628
1629 I2C_INIT
1630
wdenkb37c7e52003-06-30 16:24:52 +00001631 (Optional). Any commands necessary to enable the I2C
wdenk43d96162003-03-06 00:02:04 +00001632 controller or configure ports.
wdenkc6097192002-11-03 00:24:07 +00001633
wdenkba56f622004-02-06 23:19:44 +00001634 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
wdenkb37c7e52003-06-30 16:24:52 +00001635
wdenkc6097192002-11-03 00:24:07 +00001636 I2C_ACTIVE
1637
1638 The code necessary to make the I2C data line active
1639 (driven). If the data line is open collector, this
1640 define can be null.
1641
wdenkb37c7e52003-06-30 16:24:52 +00001642 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
1643
wdenkc6097192002-11-03 00:24:07 +00001644 I2C_TRISTATE
1645
1646 The code necessary to make the I2C data line tri-stated
1647 (inactive). If the data line is open collector, this
1648 define can be null.
1649
wdenkb37c7e52003-06-30 16:24:52 +00001650 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
1651
wdenkc6097192002-11-03 00:24:07 +00001652 I2C_READ
1653
York Sun472d5462013-04-01 11:29:11 -07001654 Code that returns true if the I2C data line is high,
1655 false if it is low.
wdenkc6097192002-11-03 00:24:07 +00001656
wdenkb37c7e52003-06-30 16:24:52 +00001657 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
1658
wdenkc6097192002-11-03 00:24:07 +00001659 I2C_SDA(bit)
1660
York Sun472d5462013-04-01 11:29:11 -07001661 If <bit> is true, sets the I2C data line high. If it
1662 is false, it clears it (low).
wdenkc6097192002-11-03 00:24:07 +00001663
wdenkb37c7e52003-06-30 16:24:52 +00001664 eg: #define I2C_SDA(bit) \
wdenk2535d602003-07-17 23:16:40 +00001665 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
wdenkba56f622004-02-06 23:19:44 +00001666 else immr->im_cpm.cp_pbdat &= ~PB_SDA
wdenkb37c7e52003-06-30 16:24:52 +00001667
wdenkc6097192002-11-03 00:24:07 +00001668 I2C_SCL(bit)
1669
York Sun472d5462013-04-01 11:29:11 -07001670 If <bit> is true, sets the I2C clock line high. If it
1671 is false, it clears it (low).
wdenkc6097192002-11-03 00:24:07 +00001672
wdenkb37c7e52003-06-30 16:24:52 +00001673 eg: #define I2C_SCL(bit) \
wdenk2535d602003-07-17 23:16:40 +00001674 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
wdenkba56f622004-02-06 23:19:44 +00001675 else immr->im_cpm.cp_pbdat &= ~PB_SCL
wdenkb37c7e52003-06-30 16:24:52 +00001676
wdenkc6097192002-11-03 00:24:07 +00001677 I2C_DELAY
1678
1679 This delay is invoked four times per clock cycle so this
1680 controls the rate of data transfer. The data rate thus
wdenkb37c7e52003-06-30 16:24:52 +00001681 is 1 / (I2C_DELAY * 4). Often defined to be something
wdenk945af8d2003-07-16 21:53:01 +00001682 like:
1683
wdenkb37c7e52003-06-30 16:24:52 +00001684 #define I2C_DELAY udelay(2)
wdenkc6097192002-11-03 00:24:07 +00001685
Mike Frysinger793b5722010-07-21 13:38:02 -04001686 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA
1687
1688 If your arch supports the generic GPIO framework (asm/gpio.h),
1689 then you may alternatively define the two GPIOs that are to be
1690 used as SCL / SDA. Any of the previous I2C_xxx macros will
1691 have GPIO-based defaults assigned to them as appropriate.
1692
1693 You should define these to the GPIO value as given directly to
1694 the generic GPIO functions.
1695
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001696 CONFIG_SYS_I2C_INIT_BOARD
wdenk47cd00f2003-03-06 13:39:27 +00001697
wdenk8bde7f72003-06-27 21:31:46 +00001698 When a board is reset during an i2c bus transfer
1699 chips might think that the current transfer is still
1700 in progress. On some boards it is possible to access
1701 the i2c SCLK line directly, either by using the
1702 processor pin as a GPIO or by having a second pin
1703 connected to the bus. If this option is defined a
1704 custom i2c_init_board() routine in boards/xxx/board.c
1705 is run early in the boot sequence.
wdenk47cd00f2003-03-06 13:39:27 +00001706
Ben Warrenbb99ad62006-09-07 16:50:54 -04001707 CONFIG_I2C_MULTI_BUS
1708
1709 This option allows the use of multiple I2C buses, each of which
Wolfgang Denkc0f40852011-10-26 10:21:21 +00001710 must have a controller. At any point in time, only one bus is
1711 active. To switch to a different bus, use the 'i2c dev' command.
Ben Warrenbb99ad62006-09-07 16:50:54 -04001712 Note that bus numbering is zero-based.
1713
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001714 CONFIG_SYS_I2C_NOPROBES
Ben Warrenbb99ad62006-09-07 16:50:54 -04001715
1716 This option specifies a list of I2C devices that will be skipped
Wolfgang Denkc0f40852011-10-26 10:21:21 +00001717 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS
Peter Tyser0f89c542009-04-18 22:34:03 -05001718 is set, specify a list of bus-device pairs. Otherwise, specify
1719 a 1D array of device addresses
Ben Warrenbb99ad62006-09-07 16:50:54 -04001720
1721 e.g.
1722 #undef CONFIG_I2C_MULTI_BUS
Wolfgang Denkc0f40852011-10-26 10:21:21 +00001723 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68}
Ben Warrenbb99ad62006-09-07 16:50:54 -04001724
1725 will skip addresses 0x50 and 0x68 on a board with one I2C bus
1726
Wolfgang Denkc0f40852011-10-26 10:21:21 +00001727 #define CONFIG_I2C_MULTI_BUS
Simon Glass945a18e2016-10-02 18:01:05 -06001728 #define CONFIG_SYS_I2C_NOPROBES {{0,0x50},{0,0x68},{1,0x54}}
Ben Warrenbb99ad62006-09-07 16:50:54 -04001729
1730 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1
1731
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001732 CONFIG_SYS_SPD_BUS_NUM
Timur Tabibe5e6182006-11-03 19:15:00 -06001733
1734 If defined, then this indicates the I2C bus number for DDR SPD.
1735 If not defined, then U-Boot assumes that SPD is on I2C bus 0.
1736
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001737 CONFIG_SYS_RTC_BUS_NUM
Stefan Roese0dc018e2007-02-20 10:51:26 +01001738
1739 If defined, then this indicates the I2C bus number for the RTC.
1740 If not defined, then U-Boot assumes that RTC is on I2C bus 0.
1741
Andrew Dyer2ac69852008-12-29 17:36:01 -06001742 CONFIG_SOFT_I2C_READ_REPEATED_START
1743
1744 defining this will force the i2c_read() function in
1745 the soft_i2c driver to perform an I2C repeated start
1746 between writing the address pointer and reading the
1747 data. If this define is omitted the default behaviour
1748 of doing a stop-start sequence will be used. Most I2C
1749 devices can use either method, but some require one or
1750 the other.
Timur Tabibe5e6182006-11-03 19:15:00 -06001751
wdenkc6097192002-11-03 00:24:07 +00001752- SPI Support: CONFIG_SPI
1753
1754 Enables SPI driver (so far only tested with
1755 SPI EEPROM, also an instance works with Crystal A/D and
1756 D/As on the SACSng board)
1757
wdenkc6097192002-11-03 00:24:07 +00001758 CONFIG_SOFT_SPI
1759
wdenk43d96162003-03-06 00:02:04 +00001760 Enables a software (bit-bang) SPI driver rather than
1761 using hardware support. This is a general purpose
1762 driver that only requires three general I/O port pins
1763 (two outputs, one input) to function. If this is
1764 defined, the board configuration must define several
1765 SPI configuration items (port pins to use, etc). For
1766 an example, see include/configs/sacsng.h.
wdenkc6097192002-11-03 00:24:07 +00001767
Heiko Schocherf659b572014-07-14 10:22:11 +02001768 CONFIG_SYS_SPI_MXC_WAIT
1769 Timeout for waiting until spi transfer completed.
1770 default: (CONFIG_SYS_HZ/100) /* 10 ms */
1771
Matthias Fuchs01335022007-12-27 17:12:34 +01001772- FPGA Support: CONFIG_FPGA
1773
1774 Enables FPGA subsystem.
1775
1776 CONFIG_FPGA_<vendor>
1777
1778 Enables support for specific chip vendors.
1779 (ALTERA, XILINX)
1780
1781 CONFIG_FPGA_<family>
1782
1783 Enables support for FPGA family.
1784 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
1785
1786 CONFIG_FPGA_COUNT
wdenkc6097192002-11-03 00:24:07 +00001787
wdenk43d96162003-03-06 00:02:04 +00001788 Specify the number of FPGA devices to support.
wdenkc6097192002-11-03 00:24:07 +00001789
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001790 CONFIG_SYS_FPGA_PROG_FEEDBACK
wdenkc6097192002-11-03 00:24:07 +00001791
wdenk8bde7f72003-06-27 21:31:46 +00001792 Enable printing of hash marks during FPGA configuration.
wdenkc6097192002-11-03 00:24:07 +00001793
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001794 CONFIG_SYS_FPGA_CHECK_BUSY
wdenkc6097192002-11-03 00:24:07 +00001795
wdenk43d96162003-03-06 00:02:04 +00001796 Enable checks on FPGA configuration interface busy
1797 status by the configuration function. This option
1798 will require a board or device specific function to
1799 be written.
wdenkc6097192002-11-03 00:24:07 +00001800
1801 CONFIG_FPGA_DELAY
1802
1803 If defined, a function that provides delays in the FPGA
1804 configuration driver.
1805
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001806 CONFIG_SYS_FPGA_CHECK_CTRLC
wdenkc6097192002-11-03 00:24:07 +00001807 Allow Control-C to interrupt FPGA configuration
1808
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001809 CONFIG_SYS_FPGA_CHECK_ERROR
wdenkc6097192002-11-03 00:24:07 +00001810
wdenk43d96162003-03-06 00:02:04 +00001811 Check for configuration errors during FPGA bitfile
1812 loading. For example, abort during Virtex II
1813 configuration if the INIT_B line goes low (which
1814 indicated a CRC error).
wdenkc6097192002-11-03 00:24:07 +00001815
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001816 CONFIG_SYS_FPGA_WAIT_INIT
wdenkc6097192002-11-03 00:24:07 +00001817
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08001818 Maximum time to wait for the INIT_B line to de-assert
1819 after PROB_B has been de-asserted during a Virtex II
wdenk43d96162003-03-06 00:02:04 +00001820 FPGA configuration sequence. The default time is 500
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001821 ms.
wdenkc6097192002-11-03 00:24:07 +00001822
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001823 CONFIG_SYS_FPGA_WAIT_BUSY
wdenkc6097192002-11-03 00:24:07 +00001824
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08001825 Maximum time to wait for BUSY to de-assert during
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001826 Virtex II FPGA configuration. The default is 5 ms.
wdenkc6097192002-11-03 00:24:07 +00001827
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001828 CONFIG_SYS_FPGA_WAIT_CONFIG
wdenkc6097192002-11-03 00:24:07 +00001829
wdenk43d96162003-03-06 00:02:04 +00001830 Time to wait after FPGA configuration. The default is
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001831 200 ms.
wdenkc6097192002-11-03 00:24:07 +00001832
1833- Configuration Management:
Stefan Roeseb2b8a692014-10-22 12:13:24 +02001834
wdenkc6097192002-11-03 00:24:07 +00001835 CONFIG_IDENT_STRING
1836
wdenk43d96162003-03-06 00:02:04 +00001837 If defined, this string will be added to the U-Boot
1838 version information (U_BOOT_VERSION)
wdenkc6097192002-11-03 00:24:07 +00001839
1840- Vendor Parameter Protection:
1841
wdenk43d96162003-03-06 00:02:04 +00001842 U-Boot considers the values of the environment
1843 variables "serial#" (Board Serial Number) and
wdenk7152b1d2003-09-05 23:19:14 +00001844 "ethaddr" (Ethernet Address) to be parameters that
wdenk43d96162003-03-06 00:02:04 +00001845 are set once by the board vendor / manufacturer, and
1846 protects these variables from casual modification by
1847 the user. Once set, these variables are read-only,
1848 and write or delete attempts are rejected. You can
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001849 change this behaviour:
wdenkc6097192002-11-03 00:24:07 +00001850
1851 If CONFIG_ENV_OVERWRITE is #defined in your config
1852 file, the write protection for vendor parameters is
wdenk47cd00f2003-03-06 13:39:27 +00001853 completely disabled. Anybody can change or delete
wdenkc6097192002-11-03 00:24:07 +00001854 these parameters.
1855
Joe Hershberger92ac5202015-05-04 14:55:14 -05001856 Alternatively, if you define _both_ an ethaddr in the
1857 default env _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001858 Ethernet address is installed in the environment,
wdenkc6097192002-11-03 00:24:07 +00001859 which can be changed exactly ONCE by the user. [The
1860 serial# is unaffected by this, i. e. it remains
1861 read-only.]
1862
Joe Hershberger25980902012-12-11 22:16:31 -06001863 The same can be accomplished in a more flexible way
1864 for any variable by configuring the type of access
1865 to allow for those variables in the ".flags" variable
1866 or define CONFIG_ENV_FLAGS_LIST_STATIC.
1867
wdenkc6097192002-11-03 00:24:07 +00001868- Protected RAM:
1869 CONFIG_PRAM
1870
1871 Define this variable to enable the reservation of
1872 "protected RAM", i. e. RAM which is not overwritten
1873 by U-Boot. Define CONFIG_PRAM to hold the number of
1874 kB you want to reserve for pRAM. You can overwrite
1875 this default value by defining an environment
1876 variable "pram" to the number of kB you want to
1877 reserve. Note that the board info structure will
1878 still show the full amount of RAM. If pRAM is
1879 reserved, a new environment variable "mem" will
1880 automatically be defined to hold the amount of
1881 remaining RAM in a form that can be passed as boot
1882 argument to Linux, for instance like that:
1883
Wolfgang Denkfe126d82005-11-20 21:40:11 +01001884 setenv bootargs ... mem=\${mem}
wdenkc6097192002-11-03 00:24:07 +00001885 saveenv
1886
1887 This way you can tell Linux not to use this memory,
1888 either, which results in a memory region that will
1889 not be affected by reboots.
1890
1891 *WARNING* If your board configuration uses automatic
1892 detection of the RAM size, you must make sure that
1893 this memory test is non-destructive. So far, the
1894 following board configurations are known to be
1895 "pRAM-clean":
1896
Heiko Schocher5b8e76c2017-06-07 17:33:09 +02001897 IVMS8, IVML24, SPD8xx,
Wolfgang Denk1b0757e2012-10-24 02:36:15 +00001898 HERMES, IP860, RPXlite, LWMON,
Heiko Schocher2eb48ff2017-06-07 17:33:10 +02001899 FLAGADM
wdenkc6097192002-11-03 00:24:07 +00001900
Gabe Black40fef042012-12-02 04:55:18 +00001901- Access to physical memory region (> 4GB)
1902 Some basic support is provided for operations on memory not
1903 normally accessible to U-Boot - e.g. some architectures
1904 support access to more than 4GB of memory on 32-bit
1905 machines using physical address extension or similar.
1906 Define CONFIG_PHYSMEM to access this basic support, which
1907 currently only supports clearing the memory.
1908
wdenkc6097192002-11-03 00:24:07 +00001909- Error Recovery:
wdenkc6097192002-11-03 00:24:07 +00001910 CONFIG_NET_RETRY_COUNT
1911
wdenk43d96162003-03-06 00:02:04 +00001912 This variable defines the number of retries for
1913 network operations like ARP, RARP, TFTP, or BOOTP
1914 before giving up the operation. If not defined, a
1915 default value of 5 is used.
wdenkc6097192002-11-03 00:24:07 +00001916
Guennadi Liakhovetski40cb90e2008-04-03 17:04:19 +02001917 CONFIG_ARP_TIMEOUT
1918
1919 Timeout waiting for an ARP reply in milliseconds.
1920
Tetsuyuki Kobayashi48a3e992012-07-03 22:25:21 +00001921 CONFIG_NFS_TIMEOUT
1922
1923 Timeout in milliseconds used in NFS protocol.
1924 If you encounter "ERROR: Cannot umount" in nfs command,
1925 try longer timeout such as
1926 #define CONFIG_NFS_TIMEOUT 10000UL
1927
wdenkc6097192002-11-03 00:24:07 +00001928- Command Interpreter:
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001929 CONFIG_SYS_PROMPT_HUSH_PS2
wdenkc6097192002-11-03 00:24:07 +00001930
1931 This defines the secondary prompt string, which is
1932 printed when the command interpreter needs more input
1933 to complete a command. Usually "> ".
1934
1935 Note:
1936
wdenk8bde7f72003-06-27 21:31:46 +00001937 In the current implementation, the local variables
1938 space and global environment variables space are
1939 separated. Local variables are those you define by
1940 simply typing `name=value'. To access a local
1941 variable later on, you have write `$name' or
1942 `${name}'; to execute the contents of a variable
1943 directly type `$name' at the command prompt.
wdenkc6097192002-11-03 00:24:07 +00001944
wdenk43d96162003-03-06 00:02:04 +00001945 Global environment variables are those you use
1946 setenv/printenv to work with. To run a command stored
1947 in such a variable, you need to use the run command,
1948 and you must not use the '$' sign to access them.
wdenkc6097192002-11-03 00:24:07 +00001949
1950 To store commands and special characters in a
1951 variable, please use double quotation marks
1952 surrounding the whole text of the variable, instead
1953 of the backslashes before semicolons and special
1954 symbols.
1955
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08001956- Command Line Editing and History:
Marek Vasutf3b267b2016-01-27 04:47:55 +01001957 CONFIG_CMDLINE_PS_SUPPORT
1958
1959 Enable support for changing the command prompt string
1960 at run-time. Only static string is supported so far.
1961 The string is obtained from environment variables PS1
1962 and PS2.
1963
wdenka8c7c702003-12-06 19:49:23 +00001964- Default Environment:
wdenkc6097192002-11-03 00:24:07 +00001965 CONFIG_EXTRA_ENV_SETTINGS
1966
wdenk43d96162003-03-06 00:02:04 +00001967 Define this to contain any number of null terminated
1968 strings (variable = value pairs) that will be part of
wdenk7152b1d2003-09-05 23:19:14 +00001969 the default environment compiled into the boot image.
wdenk2262cfe2002-11-18 00:14:45 +00001970
wdenk43d96162003-03-06 00:02:04 +00001971 For example, place something like this in your
1972 board's config file:
wdenkc6097192002-11-03 00:24:07 +00001973
1974 #define CONFIG_EXTRA_ENV_SETTINGS \
1975 "myvar1=value1\0" \
1976 "myvar2=value2\0"
1977
wdenk43d96162003-03-06 00:02:04 +00001978 Warning: This method is based on knowledge about the
1979 internal format how the environment is stored by the
1980 U-Boot code. This is NOT an official, exported
1981 interface! Although it is unlikely that this format
wdenk7152b1d2003-09-05 23:19:14 +00001982 will change soon, there is no guarantee either.
wdenkc6097192002-11-03 00:24:07 +00001983 You better know what you are doing here.
1984
wdenk43d96162003-03-06 00:02:04 +00001985 Note: overly (ab)use of the default environment is
1986 discouraged. Make sure to check other ways to preset
Wolfgang Denk74de7ae2009-04-01 23:34:12 +02001987 the environment like the "source" command or the
wdenk43d96162003-03-06 00:02:04 +00001988 boot command first.
wdenkc6097192002-11-03 00:24:07 +00001989
Simon Glass06fd8532012-11-30 13:01:17 +00001990 CONFIG_DELAY_ENVIRONMENT
1991
1992 Normally the environment is loaded when the board is
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08001993 initialised so that it is available to U-Boot. This inhibits
Simon Glass06fd8532012-11-30 13:01:17 +00001994 that so that the environment is not available until
1995 explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL
1996 this is instead controlled by the value of
1997 /config/load-environment.
1998
Wolfgang Denkecb0ccd2005-09-24 22:37:32 +02001999- TFTP Fixed UDP Port:
2000 CONFIG_TFTP_PORT
2001
Wolfgang Denk28cb9372005-09-24 23:25:46 +02002002 If this is defined, the environment variable tftpsrcp
Wolfgang Denkecb0ccd2005-09-24 22:37:32 +02002003 is used to supply the TFTP UDP source port value.
Wolfgang Denk28cb9372005-09-24 23:25:46 +02002004 If tftpsrcp isn't defined, the normal pseudo-random port
Wolfgang Denkecb0ccd2005-09-24 22:37:32 +02002005 number generator is used.
2006
Wolfgang Denk28cb9372005-09-24 23:25:46 +02002007 Also, the environment variable tftpdstp is used to supply
2008 the TFTP UDP destination port value. If tftpdstp isn't
2009 defined, the normal port 69 is used.
2010
2011 The purpose for tftpsrcp is to allow a TFTP server to
Wolfgang Denkecb0ccd2005-09-24 22:37:32 +02002012 blindly start the TFTP transfer using the pre-configured
2013 target IP address and UDP port. This has the effect of
2014 "punching through" the (Windows XP) firewall, allowing
2015 the remainder of the TFTP transfer to proceed normally.
2016 A better solution is to properly configure the firewall,
2017 but sometimes that is not allowed.
2018
Wolfgang Denk4cf26092011-10-07 09:58:21 +02002019 CONFIG_STANDALONE_LOAD_ADDR
2020
Wolfgang Denk6feff892011-10-09 21:06:34 +02002021 This option defines a board specific value for the
2022 address where standalone program gets loaded, thus
2023 overwriting the architecture dependent default
Wolfgang Denk4cf26092011-10-07 09:58:21 +02002024 settings.
2025
2026- Frame Buffer Address:
2027 CONFIG_FB_ADDR
2028
2029 Define CONFIG_FB_ADDR if you want to use specific
Wolfgang Denk44a53b52013-01-03 00:43:59 +00002030 address for frame buffer. This is typically the case
2031 when using a graphics controller has separate video
2032 memory. U-Boot will then place the frame buffer at
2033 the given address instead of dynamically reserving it
2034 in system RAM by calling lcd_setmem(), which grabs
2035 the memory for the frame buffer depending on the
2036 configured panel size.
Wolfgang Denk4cf26092011-10-07 09:58:21 +02002037
2038 Please see board_init_f function.
2039
Detlev Zundelcccfc2a2009-12-01 17:16:19 +01002040- Automatic software updates via TFTP server
2041 CONFIG_UPDATE_TFTP
2042 CONFIG_UPDATE_TFTP_CNT_MAX
2043 CONFIG_UPDATE_TFTP_MSEC_MAX
2044
2045 These options enable and control the auto-update feature;
2046 for a more detailed description refer to doc/README.update.
2047
2048- MTD Support (mtdparts command, UBI support)
Heiko Schocherff94bc42014-06-24 10:10:04 +02002049 CONFIG_MTD_UBI_WL_THRESHOLD
2050 This parameter defines the maximum difference between the highest
2051 erase counter value and the lowest erase counter value of eraseblocks
2052 of UBI devices. When this threshold is exceeded, UBI starts performing
2053 wear leveling by means of moving data from eraseblock with low erase
2054 counter to eraseblocks with high erase counter.
2055
2056 The default value should be OK for SLC NAND flashes, NOR flashes and
2057 other flashes which have eraseblock life-cycle 100000 or more.
2058 However, in case of MLC NAND flashes which typically have eraseblock
2059 life-cycle less than 10000, the threshold should be lessened (e.g.,
2060 to 128 or 256, although it does not have to be power of 2).
2061
2062 default: 4096
Simon Glassc654b512014-10-23 18:58:54 -06002063
Heiko Schocherff94bc42014-06-24 10:10:04 +02002064 CONFIG_MTD_UBI_BEB_LIMIT
2065 This option specifies the maximum bad physical eraseblocks UBI
2066 expects on the MTD device (per 1024 eraseblocks). If the
2067 underlying flash does not admit of bad eraseblocks (e.g. NOR
2068 flash), this value is ignored.
2069
2070 NAND datasheets often specify the minimum and maximum NVM
2071 (Number of Valid Blocks) for the flashes' endurance lifetime.
2072 The maximum expected bad eraseblocks per 1024 eraseblocks
2073 then can be calculated as "1024 * (1 - MinNVB / MaxNVB)",
2074 which gives 20 for most NANDs (MaxNVB is basically the total
2075 count of eraseblocks on the chip).
2076
2077 To put it differently, if this value is 20, UBI will try to
2078 reserve about 1.9% of physical eraseblocks for bad blocks
2079 handling. And that will be 1.9% of eraseblocks on the entire
2080 NAND chip, not just the MTD partition UBI attaches. This means
2081 that if you have, say, a NAND flash chip admits maximum 40 bad
2082 eraseblocks, and it is split on two MTD partitions of the same
2083 size, UBI will reserve 40 eraseblocks when attaching a
2084 partition.
2085
2086 default: 20
2087
2088 CONFIG_MTD_UBI_FASTMAP
2089 Fastmap is a mechanism which allows attaching an UBI device
2090 in nearly constant time. Instead of scanning the whole MTD device it
2091 only has to locate a checkpoint (called fastmap) on the device.
2092 The on-flash fastmap contains all information needed to attach
2093 the device. Using fastmap makes only sense on large devices where
2094 attaching by scanning takes long. UBI will not automatically install
2095 a fastmap on old images, but you can set the UBI parameter
2096 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT to 1 if you want so. Please note
2097 that fastmap-enabled images are still usable with UBI implementations
2098 without fastmap support. On typical flash devices the whole fastmap
2099 fits into one PEB. UBI will reserve PEBs to hold two fastmaps.
2100
2101 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT
2102 Set this parameter to enable fastmap automatically on images
2103 without a fastmap.
2104 default: 0
2105
Heiko Schocher0195a7b2015-10-22 06:19:21 +02002106 CONFIG_MTD_UBI_FM_DEBUG
2107 Enable UBI fastmap debug
2108 default: 0
2109
Daniel Schwierzeck6a11cf42011-07-18 07:48:07 +00002110- SPL framework
Wolfgang Denk04e5ae72011-09-11 21:24:09 +02002111 CONFIG_SPL
2112 Enable building of SPL globally.
Daniel Schwierzeck6a11cf42011-07-18 07:48:07 +00002113
Tom Rini95579792012-02-14 07:29:40 +00002114 CONFIG_SPL_LDSCRIPT
2115 LDSCRIPT for linking the SPL binary.
2116
Albert ARIBAUD6ebc3462013-04-12 05:14:30 +00002117 CONFIG_SPL_MAX_FOOTPRINT
2118 Maximum size in memory allocated to the SPL, BSS included.
2119 When defined, the linker checks that the actual memory
2120 used by SPL from _start to __bss_end does not exceed it.
Albert ARIBAUD8960af82013-04-14 04:48:38 +00002121 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
Albert ARIBAUD6ebc3462013-04-12 05:14:30 +00002122 must not be both defined at the same time.
2123
Tom Rini95579792012-02-14 07:29:40 +00002124 CONFIG_SPL_MAX_SIZE
Albert ARIBAUD6ebc3462013-04-12 05:14:30 +00002125 Maximum size of the SPL image (text, data, rodata, and
2126 linker lists sections), BSS excluded.
2127 When defined, the linker checks that the actual size does
2128 not exceed it.
Tom Rini95579792012-02-14 07:29:40 +00002129
Scott Wood94a45bb2012-09-20 19:05:12 -05002130 CONFIG_SPL_RELOC_TEXT_BASE
2131 Address to relocate to. If unspecified, this is equal to
2132 CONFIG_SPL_TEXT_BASE (i.e. no relocation is done).
2133
Tom Rini95579792012-02-14 07:29:40 +00002134 CONFIG_SPL_BSS_START_ADDR
2135 Link address for the BSS within the SPL binary.
2136
2137 CONFIG_SPL_BSS_MAX_SIZE
Albert ARIBAUD6ebc3462013-04-12 05:14:30 +00002138 Maximum size in memory allocated to the SPL BSS.
2139 When defined, the linker checks that the actual memory used
2140 by SPL from __bss_start to __bss_end does not exceed it.
Albert ARIBAUD8960af82013-04-14 04:48:38 +00002141 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
Albert ARIBAUD6ebc3462013-04-12 05:14:30 +00002142 must not be both defined at the same time.
Tom Rini95579792012-02-14 07:29:40 +00002143
2144 CONFIG_SPL_STACK
2145 Adress of the start of the stack SPL will use
2146
Albert ARIBAUD \(3ADEV\)8c80eb32015-03-31 11:40:50 +02002147 CONFIG_SPL_PANIC_ON_RAW_IMAGE
2148 When defined, SPL will panic() if the image it has
2149 loaded does not have a signature.
2150 Defining this is useful when code which loads images
2151 in SPL cannot guarantee that absolutely all read errors
2152 will be caught.
2153 An example is the LPC32XX MLC NAND driver, which will
2154 consider that a completely unreadable NAND block is bad,
2155 and thus should be skipped silently.
2156
Scott Wood94a45bb2012-09-20 19:05:12 -05002157 CONFIG_SPL_RELOC_STACK
2158 Adress of the start of the stack SPL will use after
2159 relocation. If unspecified, this is equal to
2160 CONFIG_SPL_STACK.
2161
Tom Rini95579792012-02-14 07:29:40 +00002162 CONFIG_SYS_SPL_MALLOC_START
2163 Starting address of the malloc pool used in SPL.
Fabio Estevam9ac4fc82015-11-12 12:30:19 -02002164 When this option is set the full malloc is used in SPL and
2165 it is set up by spl_init() and before that, the simple malloc()
2166 can be used if CONFIG_SYS_MALLOC_F is defined.
Tom Rini95579792012-02-14 07:29:40 +00002167
2168 CONFIG_SYS_SPL_MALLOC_SIZE
2169 The size of the malloc pool used in SPL.
Daniel Schwierzeck6a11cf42011-07-18 07:48:07 +00002170
Tom Rini9607faf2014-03-28 12:03:39 -04002171 CONFIG_SPL_OS_BOOT
2172 Enable booting directly to an OS from SPL.
2173 See also: doc/README.falcon
2174
Tom Rini861a86f2012-08-13 11:37:56 -07002175 CONFIG_SPL_DISPLAY_PRINT
2176 For ARM, enable an optional function to print more information
2177 about the running system.
2178
Scott Wood4b919722012-09-20 16:35:21 -05002179 CONFIG_SPL_INIT_MINIMAL
2180 Arch init code should be built for a very small image
2181
Paul Kocialkowskib97300b2014-11-08 23:14:56 +01002182 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_PARTITION
2183 Partition on the MMC to load U-Boot from when the MMC is being
2184 used in raw mode
2185
Peter Korsgaard2b75b0a2013-05-13 08:36:29 +00002186 CONFIG_SYS_MMCSD_RAW_MODE_KERNEL_SECTOR
2187 Sector to load kernel uImage from when MMC is being
2188 used in raw mode (for Falcon mode)
2189
2190 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTOR,
2191 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTORS
2192 Sector and number of sectors to load kernel argument
2193 parameters from when MMC is being used in raw mode
2194 (for falcon mode)
2195
Guillaume GARDETfae81c72014-10-15 17:53:13 +02002196 CONFIG_SPL_FS_LOAD_PAYLOAD_NAME
2197 Filename to read to load U-Boot when reading from filesystem
2198
2199 CONFIG_SPL_FS_LOAD_KERNEL_NAME
Peter Korsgaard7ad2cc72013-05-13 08:36:27 +00002200 Filename to read to load kernel uImage when reading
Guillaume GARDETfae81c72014-10-15 17:53:13 +02002201 from filesystem (for Falcon mode)
Peter Korsgaard7ad2cc72013-05-13 08:36:27 +00002202
Guillaume GARDETfae81c72014-10-15 17:53:13 +02002203 CONFIG_SPL_FS_LOAD_ARGS_NAME
Peter Korsgaard7ad2cc72013-05-13 08:36:27 +00002204 Filename to read to load kernel argument parameters
Guillaume GARDETfae81c72014-10-15 17:53:13 +02002205 when reading from filesystem (for Falcon mode)
Peter Korsgaard7ad2cc72013-05-13 08:36:27 +00002206
Scott Wood06f60ae2012-12-06 13:33:17 +00002207 CONFIG_SPL_MPC83XX_WAIT_FOR_NAND
2208 Set this for NAND SPL on PPC mpc83xx targets, so that
2209 start.S waits for the rest of the SPL to load before
2210 continuing (the hardware starts execution after just
2211 loading the first page rather than the full 4K).
2212
Prabhakar Kushwaha651fcf62014-04-08 19:12:31 +05302213 CONFIG_SPL_SKIP_RELOCATE
2214 Avoid SPL relocation
2215
Jörg Krause15e207f2018-01-14 19:26:38 +01002216 CONFIG_SPL_NAND_IDENT
2217 SPL uses the chip ID list to identify the NAND flash.
2218 Requires CONFIG_SPL_NAND_BASE.
2219
Thomas Gleixner6f4e7d32016-07-12 20:28:12 +02002220 CONFIG_SPL_UBI
2221 Support for a lightweight UBI (fastmap) scanner and
2222 loader
2223
Heiko Schocher0c3117b2014-10-31 08:31:00 +01002224 CONFIG_SPL_NAND_RAW_ONLY
2225 Support to boot only raw u-boot.bin images. Use this only
2226 if you need to save space.
2227
Ying Zhang7c8eea52013-08-16 15:16:12 +08002228 CONFIG_SPL_COMMON_INIT_DDR
2229 Set for common ddr init with serial presence detect in
2230 SPL binary.
2231
Tom Rini95579792012-02-14 07:29:40 +00002232 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT,
2233 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE,
2234 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS,
2235 CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE,
2236 CONFIG_SYS_NAND_ECCBYTES
2237 Defines the size and behavior of the NAND that SPL uses
Scott Wood7d4b7952012-09-21 18:35:27 -05002238 to read U-Boot
Tom Rini95579792012-02-14 07:29:40 +00002239
2240 CONFIG_SYS_NAND_U_BOOT_OFFS
Scott Wood7d4b7952012-09-21 18:35:27 -05002241 Location in NAND to read U-Boot from
2242
2243 CONFIG_SYS_NAND_U_BOOT_DST
2244 Location in memory to load U-Boot to
2245
2246 CONFIG_SYS_NAND_U_BOOT_SIZE
2247 Size of image to load
Tom Rini95579792012-02-14 07:29:40 +00002248
2249 CONFIG_SYS_NAND_U_BOOT_START
Scott Wood7d4b7952012-09-21 18:35:27 -05002250 Entry point in loaded image to jump to
Tom Rini95579792012-02-14 07:29:40 +00002251
2252 CONFIG_SYS_NAND_HW_ECC_OOBFIRST
2253 Define this if you need to first read the OOB and then the
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08002254 data. This is used, for example, on davinci platforms.
Tom Rini95579792012-02-14 07:29:40 +00002255
Pavel Machekc57b9532012-08-30 22:42:11 +02002256 CONFIG_SPL_RAM_DEVICE
2257 Support for running image already present in ram, in SPL binary
2258
Scott Wood74752ba2012-12-06 13:33:16 +00002259 CONFIG_SPL_PAD_TO
Benoît Thébaudeau6113d3f2013-04-11 09:35:49 +00002260 Image offset to which the SPL should be padded before appending
2261 the SPL payload. By default, this is defined as
2262 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
2263 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
2264 payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
Scott Wood74752ba2012-12-06 13:33:16 +00002265
Scott Woodca2fca22012-09-21 16:27:32 -05002266 CONFIG_SPL_TARGET
2267 Final target image containing SPL and payload. Some SPLs
2268 use an arch-specific makefile fragment instead, for
2269 example if more than one image needs to be produced.
2270
Marek Vasutb527b9c2018-05-13 00:22:52 +02002271 CONFIG_SPL_FIT_PRINT
Simon Glass87ebee32013-05-08 08:05:59 +00002272 Printing information about a FIT image adds quite a bit of
2273 code to SPL. So this is normally disabled in SPL. Use this
2274 option to re-enable it. This will affect the output of the
2275 bootm command when booting a FIT image.
2276
Ying Zhang3aa29de2013-08-16 15:16:15 +08002277- TPL framework
2278 CONFIG_TPL
2279 Enable building of TPL globally.
2280
2281 CONFIG_TPL_PAD_TO
2282 Image offset to which the TPL should be padded before appending
2283 the TPL payload. By default, this is defined as
Wolfgang Denk93e14592013-10-04 17:43:24 +02002284 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
2285 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
2286 payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
Ying Zhang3aa29de2013-08-16 15:16:15 +08002287
wdenka8c7c702003-12-06 19:49:23 +00002288- Interrupt support (PPC):
2289
wdenkd4ca31c2004-01-02 14:00:00 +00002290 There are common interrupt_init() and timer_interrupt()
2291 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002292 for CPU specific initialization. interrupt_init_cpu()
wdenkd4ca31c2004-01-02 14:00:00 +00002293 should set decrementer_count to appropriate value. If
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002294 CPU resets decrementer automatically after interrupt
wdenkd4ca31c2004-01-02 14:00:00 +00002295 (ppc4xx) it should set decrementer_count to zero.
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002296 timer_interrupt() calls timer_interrupt_cpu() for CPU
wdenkd4ca31c2004-01-02 14:00:00 +00002297 specific handling. If board has watchdog / status_led
2298 / other_activity_monitor it works automatically from
2299 general timer_interrupt().
wdenka8c7c702003-12-06 19:49:23 +00002300
wdenkc6097192002-11-03 00:24:07 +00002301
Helmut Raiger9660e442011-10-20 04:19:47 +00002302Board initialization settings:
2303------------------------------
2304
2305During Initialization u-boot calls a number of board specific functions
2306to allow the preparation of board specific prerequisites, e.g. pin setup
2307before drivers are initialized. To enable these callbacks the
2308following configuration macros have to be defined. Currently this is
2309architecture specific, so please check arch/your_architecture/lib/board.c
2310typically in board_init_f() and board_init_r().
2311
2312- CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f()
2313- CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r()
2314- CONFIG_BOARD_LATE_INIT: Call board_late_init()
2315- CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init()
wdenkc6097192002-11-03 00:24:07 +00002316
wdenkc6097192002-11-03 00:24:07 +00002317Configuration Settings:
2318-----------------------
2319
Simon Glass4d979bf2019-12-28 10:45:10 -07002320- MEM_SUPPORT_64BIT_DATA: Defined automatically if compiled as 64-bit.
York Sun4d1fd7f2014-02-26 17:03:19 -08002321 Optionally it can be defined to support 64-bit memory commands.
2322
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002323- CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
wdenkc6097192002-11-03 00:24:07 +00002324 undefine this when you're short of memory.
2325
Peter Tyser2fb26042009-01-27 18:03:12 -06002326- CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
2327 width of the commands listed in the 'help' command output.
2328
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002329- CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to
wdenkc6097192002-11-03 00:24:07 +00002330 prompt for user input.
2331
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002332- CONFIG_SYS_CBSIZE: Buffer size for input from the Console
wdenkc6097192002-11-03 00:24:07 +00002333
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002334- CONFIG_SYS_PBSIZE: Buffer size for Console output
wdenkc6097192002-11-03 00:24:07 +00002335
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002336- CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands
wdenkc6097192002-11-03 00:24:07 +00002337
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002338- CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to
wdenkc6097192002-11-03 00:24:07 +00002339 the application (usually a Linux kernel) when it is
2340 booted
2341
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002342- CONFIG_SYS_BAUDRATE_TABLE:
wdenkc6097192002-11-03 00:24:07 +00002343 List of legal baudrate settings for this board.
2344
York Sune8149522015-12-04 11:57:07 -08002345- CONFIG_SYS_MEM_RESERVE_SECURE
York Sune61a7532016-06-24 16:46:18 -07002346 Only implemented for ARMv8 for now.
York Sune8149522015-12-04 11:57:07 -08002347 If defined, the size of CONFIG_SYS_MEM_RESERVE_SECURE memory
2348 is substracted from total RAM and won't be reported to OS.
2349 This memory can be used as secure memory. A variable
York Sune61a7532016-06-24 16:46:18 -07002350 gd->arch.secure_ram is used to track the location. In systems
York Sune8149522015-12-04 11:57:07 -08002351 the RAM base is not zero, or RAM is divided into banks,
2352 this variable needs to be recalcuated to get the address.
2353
York Sunaabd7dd2015-12-07 11:05:29 -08002354- CONFIG_SYS_MEM_TOP_HIDE:
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002355 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header,
Stefan Roese14f73ca2008-03-26 10:14:11 +01002356 this specified memory area will get subtracted from the top
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002357 (end) of RAM and won't get "touched" at all by U-Boot. By
Stefan Roese14f73ca2008-03-26 10:14:11 +01002358 fixing up gd->ram_size the Linux kernel should gets passed
2359 the now "corrected" memory size and won't touch it either.
2360 This should work for arch/ppc and arch/powerpc. Only Linux
Stefan Roese5e12e752008-03-28 11:02:53 +01002361 board ports in arch/powerpc with bootwrapper support that
Stefan Roese14f73ca2008-03-26 10:14:11 +01002362 recalculate the memory size from the SDRAM controller setup
Stefan Roese5e12e752008-03-28 11:02:53 +01002363 will have to get fixed in Linux additionally.
Stefan Roese14f73ca2008-03-26 10:14:11 +01002364
2365 This option can be used as a workaround for the 440EPx/GRx
2366 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't
2367 be touched.
2368
2369 WARNING: Please make sure that this value is a multiple of
2370 the Linux page size (normally 4k). If this is not the case,
2371 then the end address of the Linux memory will be located at a
2372 non page size aligned address and this could cause major
2373 problems.
2374
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002375- CONFIG_SYS_LOADS_BAUD_CHANGE:
wdenkc6097192002-11-03 00:24:07 +00002376 Enable temporary baudrate change while serial download
2377
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002378- CONFIG_SYS_SDRAM_BASE:
wdenkc6097192002-11-03 00:24:07 +00002379 Physical start address of SDRAM. _Must_ be 0 here.
2380
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002381- CONFIG_SYS_FLASH_BASE:
wdenkc6097192002-11-03 00:24:07 +00002382 Physical start address of Flash memory.
2383
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002384- CONFIG_SYS_MONITOR_BASE:
wdenkc6097192002-11-03 00:24:07 +00002385 Physical start address of boot monitor code (set by
2386 make config files to be same as the text base address
Wolfgang Denk14d0a022010-10-07 21:51:12 +02002387 (CONFIG_SYS_TEXT_BASE) used when linking) - same as
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002388 CONFIG_SYS_FLASH_BASE when booting from flash.
wdenkc6097192002-11-03 00:24:07 +00002389
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002390- CONFIG_SYS_MONITOR_LEN:
wdenk8bde7f72003-06-27 21:31:46 +00002391 Size of memory reserved for monitor code, used to
2392 determine _at_compile_time_ (!) if the environment is
2393 embedded within the U-Boot image, or in a separate
2394 flash sector.
wdenkc6097192002-11-03 00:24:07 +00002395
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002396- CONFIG_SYS_MALLOC_LEN:
wdenkc6097192002-11-03 00:24:07 +00002397 Size of DRAM reserved for malloc() use.
2398
Simon Glassd59476b2014-07-10 22:23:28 -06002399- CONFIG_SYS_MALLOC_F_LEN
2400 Size of the malloc() pool for use before relocation. If
2401 this is defined, then a very simple malloc() implementation
2402 will become available before relocation. The address is just
2403 below the global data, and the stack is moved down to make
2404 space.
2405
2406 This feature allocates regions with increasing addresses
2407 within the region. calloc() is supported, but realloc()
2408 is not available. free() is supported but does nothing.
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08002409 The memory will be freed (or in fact just forgotten) when
Simon Glassd59476b2014-07-10 22:23:28 -06002410 U-Boot relocates itself.
2411
Simon Glass38687ae2014-11-10 17:16:54 -07002412- CONFIG_SYS_MALLOC_SIMPLE
2413 Provides a simple and small malloc() and calloc() for those
2414 boards which do not use the full malloc in SPL (which is
2415 enabled with CONFIG_SYS_SPL_MALLOC_START).
2416
Thierry Reding1dfdd9b2014-12-09 22:25:22 -07002417- CONFIG_SYS_NONCACHED_MEMORY:
2418 Size of non-cached memory area. This area of memory will be
2419 typically located right below the malloc() area and mapped
2420 uncached in the MMU. This is useful for drivers that would
2421 otherwise require a lot of explicit cache maintenance. For
2422 some drivers it's also impossible to properly maintain the
2423 cache. For example if the regions that need to be flushed
2424 are not a multiple of the cache-line size, *and* padding
2425 cannot be allocated between the regions to align them (i.e.
2426 if the HW requires a contiguous array of regions, and the
2427 size of each region is not cache-aligned), then a flush of
2428 one region may result in overwriting data that hardware has
2429 written to another region in the same cache-line. This can
2430 happen for example in network drivers where descriptors for
2431 buffers are typically smaller than the CPU cache-line (e.g.
2432 16 bytes vs. 32 or 64 bytes).
2433
2434 Non-cached memory is only supported on 32-bit ARM at present.
2435
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002436- CONFIG_SYS_BOOTM_LEN:
Stefan Roese15940c92006-03-13 11:16:36 +01002437 Normally compressed uImages are limited to an
2438 uncompressed size of 8 MBytes. If this is not enough,
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002439 you can define CONFIG_SYS_BOOTM_LEN in your board config file
Stefan Roese15940c92006-03-13 11:16:36 +01002440 to adjust this setting to your needs.
2441
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002442- CONFIG_SYS_BOOTMAPSZ:
wdenkc6097192002-11-03 00:24:07 +00002443 Maximum size of memory mapped by the startup code of
2444 the Linux kernel; all data that must be processed by
Bartlomiej Sieka7d721e32008-04-14 15:44:16 +02002445 the Linux kernel (bd_info, boot arguments, FDT blob if
2446 used) must be put below this limit, unless "bootm_low"
Robert P. J. Day1bce2ae2013-09-16 07:15:45 -04002447 environment variable is defined and non-zero. In such case
Bartlomiej Sieka7d721e32008-04-14 15:44:16 +02002448 all data for the Linux kernel must be between "bootm_low"
Wolfgang Denkc0f40852011-10-26 10:21:21 +00002449 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment
Grant Likelyc3624e62011-03-28 09:58:43 +00002450 variable "bootm_mapsize" will override the value of
2451 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined,
2452 then the value in "bootm_size" will be used instead.
wdenkc6097192002-11-03 00:24:07 +00002453
John Rigbyfca43cc2010-10-13 13:57:35 -06002454- CONFIG_SYS_BOOT_RAMDISK_HIGH:
2455 Enable initrd_high functionality. If defined then the
2456 initrd_high feature is enabled and the bootm ramdisk subcommand
2457 is enabled.
2458
2459- CONFIG_SYS_BOOT_GET_CMDLINE:
2460 Enables allocating and saving kernel cmdline in space between
2461 "bootm_low" and "bootm_low" + BOOTMAPSZ.
2462
2463- CONFIG_SYS_BOOT_GET_KBD:
2464 Enables allocating and saving a kernel copy of the bd_info in
2465 space between "bootm_low" and "bootm_low" + BOOTMAPSZ.
2466
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002467- CONFIG_SYS_MAX_FLASH_BANKS:
wdenkc6097192002-11-03 00:24:07 +00002468 Max number of Flash memory banks
2469
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002470- CONFIG_SYS_MAX_FLASH_SECT:
wdenkc6097192002-11-03 00:24:07 +00002471 Max number of sectors on a Flash chip
2472
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002473- CONFIG_SYS_FLASH_ERASE_TOUT:
wdenkc6097192002-11-03 00:24:07 +00002474 Timeout for Flash erase operations (in ms)
2475
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002476- CONFIG_SYS_FLASH_WRITE_TOUT:
wdenkc6097192002-11-03 00:24:07 +00002477 Timeout for Flash write operations (in ms)
2478
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002479- CONFIG_SYS_FLASH_LOCK_TOUT
wdenk8564acf2003-07-14 22:13:32 +00002480 Timeout for Flash set sector lock bit operation (in ms)
2481
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002482- CONFIG_SYS_FLASH_UNLOCK_TOUT
wdenk8564acf2003-07-14 22:13:32 +00002483 Timeout for Flash clear lock bits operation (in ms)
2484
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002485- CONFIG_SYS_FLASH_PROTECTION
wdenk8564acf2003-07-14 22:13:32 +00002486 If defined, hardware flash sectors protection is used
2487 instead of U-Boot software protection.
2488
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002489- CONFIG_SYS_DIRECT_FLASH_TFTP:
wdenkc6097192002-11-03 00:24:07 +00002490
2491 Enable TFTP transfers directly to flash memory;
2492 without this option such a download has to be
2493 performed in two steps: (1) download to RAM, and (2)
2494 copy from RAM to flash.
2495
2496 The two-step approach is usually more reliable, since
2497 you can check if the download worked before you erase
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002498 the flash, but in some situations (when system RAM is
2499 too limited to allow for a temporary copy of the
wdenkc6097192002-11-03 00:24:07 +00002500 downloaded image) this option may be very useful.
2501
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002502- CONFIG_SYS_FLASH_CFI:
wdenk43d96162003-03-06 00:02:04 +00002503 Define if the flash driver uses extra elements in the
wdenk5653fc32004-02-08 22:55:38 +00002504 common flash structure for storing flash geometry.
2505
Jean-Christophe PLAGNIOL-VILLARD00b18832008-08-13 01:40:42 +02002506- CONFIG_FLASH_CFI_DRIVER
wdenk5653fc32004-02-08 22:55:38 +00002507 This option also enables the building of the cfi_flash driver
2508 in the drivers directory
wdenkc6097192002-11-03 00:24:07 +00002509
Piotr Ziecik91809ed2008-11-17 15:57:58 +01002510- CONFIG_FLASH_CFI_MTD
2511 This option enables the building of the cfi_mtd driver
2512 in the drivers directory. The driver exports CFI flash
2513 to the MTD layer.
2514
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002515- CONFIG_SYS_FLASH_USE_BUFFER_WRITE
Guennadi Liakhovetski96ef8312008-04-03 13:36:02 +02002516 Use buffered writes to flash.
2517
2518- CONFIG_FLASH_SPANSION_S29WS_N
2519 s29ws-n MirrorBit flash has non-standard addresses for buffered
2520 write commands.
2521
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002522- CONFIG_SYS_FLASH_QUIET_TEST
Stefan Roese5568e612005-11-22 13:20:42 +01002523 If this option is defined, the common CFI flash doesn't
2524 print it's warning upon not recognized FLASH banks. This
2525 is useful, if some of the configured banks are only
2526 optionally available.
2527
Jerry Van Baren9a042e92008-03-08 13:48:01 -05002528- CONFIG_FLASH_SHOW_PROGRESS
2529 If defined (must be an integer), print out countdown
2530 digits and dots. Recommended value: 45 (9..1) for 80
2531 column displays, 15 (3..1) for 40 column displays.
2532
Stefan Roese352ef3f2013-04-04 15:53:14 +02002533- CONFIG_FLASH_VERIFY
2534 If defined, the content of the flash (destination) is compared
2535 against the source after the write operation. An error message
2536 will be printed when the contents are not identical.
2537 Please note that this option is useless in nearly all cases,
2538 since such flash programming errors usually are detected earlier
2539 while unprotecting/erasing/programming. Please only enable
2540 this option if you really know what you are doing.
2541
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002542- CONFIG_SYS_RX_ETH_BUFFER:
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002543 Defines the number of Ethernet receive buffers. On some
2544 Ethernet controllers it is recommended to set this value
stroese53cf9432003-06-05 15:39:44 +00002545 to 8 or even higher (EEPRO100 or 405 EMAC), since all
2546 buffers can be full shortly after enabling the interface
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002547 on high Ethernet traffic.
stroese53cf9432003-06-05 15:39:44 +00002548 Defaults to 4 if not defined.
2549
Wolfgang Denkea882ba2010-06-20 23:33:59 +02002550- CONFIG_ENV_MAX_ENTRIES
2551
Wolfgang Denk071bc922010-10-27 22:48:30 +02002552 Maximum number of entries in the hash table that is used
2553 internally to store the environment settings. The default
2554 setting is supposed to be generous and should work in most
2555 cases. This setting can be used to tune behaviour; see
2556 lib/hashtable.c for details.
Wolfgang Denkea882ba2010-06-20 23:33:59 +02002557
Joe Hershberger25980902012-12-11 22:16:31 -06002558- CONFIG_ENV_FLAGS_LIST_DEFAULT
2559- CONFIG_ENV_FLAGS_LIST_STATIC
Robert P. J. Day1bce2ae2013-09-16 07:15:45 -04002560 Enable validation of the values given to environment variables when
Joe Hershberger25980902012-12-11 22:16:31 -06002561 calling env set. Variables can be restricted to only decimal,
2562 hexadecimal, or boolean. If CONFIG_CMD_NET is also defined,
2563 the variables can also be restricted to IP address or MAC address.
2564
2565 The format of the list is:
2566 type_attribute = [s|d|x|b|i|m]
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08002567 access_attribute = [a|r|o|c]
2568 attributes = type_attribute[access_attribute]
Joe Hershberger25980902012-12-11 22:16:31 -06002569 entry = variable_name[:attributes]
2570 list = entry[,list]
2571
2572 The type attributes are:
2573 s - String (default)
2574 d - Decimal
2575 x - Hexadecimal
2576 b - Boolean ([1yYtT|0nNfF])
2577 i - IP address
2578 m - MAC address
2579
Joe Hershberger267541f2012-12-11 22:16:34 -06002580 The access attributes are:
2581 a - Any (default)
2582 r - Read-only
2583 o - Write-once
2584 c - Change-default
2585
Joe Hershberger25980902012-12-11 22:16:31 -06002586 - CONFIG_ENV_FLAGS_LIST_DEFAULT
2587 Define this to a list (string) to define the ".flags"
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08002588 environment variable in the default or embedded environment.
Joe Hershberger25980902012-12-11 22:16:31 -06002589
2590 - CONFIG_ENV_FLAGS_LIST_STATIC
2591 Define this to a list (string) to define validation that
2592 should be done if an entry is not found in the ".flags"
2593 environment variable. To override a setting in the static
2594 list, simply add an entry for the same variable name to the
2595 ".flags" variable.
2596
Joe Hershbergerbdf1fe42015-05-20 14:27:20 -05002597 If CONFIG_REGEX is defined, the variable_name above is evaluated as a
2598 regular expression. This allows multiple variables to define the same
2599 flags without explicitly listing them for each variable.
2600
wdenkc6097192002-11-03 00:24:07 +00002601The following definitions that deal with the placement and management
2602of environment data (variable area); in general, we support the
2603following configurations:
2604
Mike Frysingerc3eb3fe2011-07-08 10:44:25 +00002605- CONFIG_BUILD_ENVCRC:
2606
2607 Builds up envcrc with the target environment so that external utils
2608 may easily extract it and embed it in final U-Boot images.
2609
wdenkc6097192002-11-03 00:24:07 +00002610BE CAREFUL! The first access to the environment happens quite early
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08002611in U-Boot initialization (when we try to get the setting of for the
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002612console baudrate). You *MUST* have mapped your NVRAM area then, or
wdenkc6097192002-11-03 00:24:07 +00002613U-Boot will hang.
2614
2615Please note that even with NVRAM we still use a copy of the
2616environment in RAM: we could work on NVRAM directly, but we want to
2617keep settings there always unmodified except somebody uses "saveenv"
2618to save the current settings.
2619
Liu Gang0a85a9e2012-03-08 00:33:20 +00002620BE CAREFUL! For some special cases, the local device can not use
2621"saveenv" command. For example, the local device will get the
Liu Gangfc54c7f2012-08-09 05:10:01 +00002622environment stored in a remote NOR flash by SRIO or PCIE link,
2623but it can not erase, write this NOR flash by SRIO or PCIE interface.
Liu Gang0a85a9e2012-03-08 00:33:20 +00002624
Guennadi Liakhovetskib74ab732009-05-18 16:07:22 +02002625- CONFIG_NAND_ENV_DST
2626
2627 Defines address in RAM to which the nand_spl code should copy the
2628 environment. If redundant environment is used, it will be copied to
2629 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE.
2630
Bruce Adlere881cb52007-11-02 13:15:42 -07002631Please note that the environment is read-only until the monitor
wdenkc6097192002-11-03 00:24:07 +00002632has been relocated to RAM and a RAM copy of the environment has been
Simon Glass00caae62017-08-03 12:22:12 -06002633created; also, when using EEPROM you will have to use env_get_f()
wdenkc6097192002-11-03 00:24:07 +00002634until then to read environment variables.
2635
wdenk85ec0bc2003-03-31 16:34:49 +00002636The environment is protected by a CRC32 checksum. Before the monitor
2637is relocated into RAM, as a result of a bad CRC you will be working
2638with the compiled-in default environment - *silently*!!! [This is
2639necessary, because the first environment variable we need is the
2640"baudrate" setting for the console - if we have a bad CRC, we don't
2641have any device yet where we could complain.]
wdenkc6097192002-11-03 00:24:07 +00002642
2643Note: once the monitor has been relocated, then it will complain if
2644the default environment is used; a new CRC is computed as soon as you
wdenk85ec0bc2003-03-31 16:34:49 +00002645use the "saveenv" command to store a valid environment.
wdenkc6097192002-11-03 00:24:07 +00002646
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002647- CONFIG_SYS_FAULT_ECHO_LINK_DOWN:
wdenk42d1f032003-10-15 23:53:47 +00002648 Echo the inverted Ethernet link state to the fault LED.
wdenkfc3e2162003-10-08 22:33:00 +00002649
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002650 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR
wdenkfc3e2162003-10-08 22:33:00 +00002651 also needs to be defined.
2652
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002653- CONFIG_SYS_FAULT_MII_ADDR:
wdenk42d1f032003-10-15 23:53:47 +00002654 MII address of the PHY to check for the Ethernet link state.
wdenkc6097192002-11-03 00:24:07 +00002655
Ron Madridf5675aa2009-02-18 14:30:44 -08002656- CONFIG_NS16550_MIN_FUNCTIONS:
2657 Define this if you desire to only have use of the NS16550_init
2658 and NS16550_putc functions for the serial driver located at
2659 drivers/serial/ns16550.c. This option is useful for saving
2660 space for already greatly restricted images, including but not
2661 limited to NAND_SPL configurations.
2662
Simon Glassb2b92f52012-11-30 13:01:18 +00002663- CONFIG_DISPLAY_BOARDINFO
2664 Display information about the board that U-Boot is running on
2665 when U-Boot starts up. The board function checkboard() is called
2666 to do this.
2667
Simon Glasse2e3e2b2012-11-30 13:01:19 +00002668- CONFIG_DISPLAY_BOARDINFO_LATE
2669 Similar to the previous option, but display this information
2670 later, once stdio is running and output goes to the LCD, if
2671 present.
2672
Sascha Silbefeb85802013-08-11 16:40:43 +02002673- CONFIG_BOARD_SIZE_LIMIT:
2674 Maximum size of the U-Boot image. When defined, the
2675 build system checks that the actual size does not
2676 exceed it.
2677
wdenkc6097192002-11-03 00:24:07 +00002678Low Level (hardware related) configuration options:
wdenkdc7c9a12003-03-26 06:55:25 +00002679---------------------------------------------------
wdenkc6097192002-11-03 00:24:07 +00002680
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002681- CONFIG_SYS_CACHELINE_SIZE:
wdenkc6097192002-11-03 00:24:07 +00002682 Cache Line Size of the CPU.
2683
Timur Tabie46fedf2011-08-04 18:03:41 -05002684- CONFIG_SYS_CCSRBAR_DEFAULT:
2685 Default (power-on reset) physical address of CCSR on Freescale
2686 PowerPC SOCs.
2687
2688- CONFIG_SYS_CCSRBAR:
2689 Virtual address of CCSR. On a 32-bit build, this is typically
2690 the same value as CONFIG_SYS_CCSRBAR_DEFAULT.
2691
Timur Tabie46fedf2011-08-04 18:03:41 -05002692- CONFIG_SYS_CCSRBAR_PHYS:
2693 Physical address of CCSR. CCSR can be relocated to a new
2694 physical address, if desired. In this case, this macro should
Wolfgang Denkc0f40852011-10-26 10:21:21 +00002695 be set to that address. Otherwise, it should be set to the
Timur Tabie46fedf2011-08-04 18:03:41 -05002696 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR
2697 is typically relocated on 36-bit builds. It is recommended
2698 that this macro be defined via the _HIGH and _LOW macros:
2699
2700 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH
2701 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW)
2702
2703- CONFIG_SYS_CCSRBAR_PHYS_HIGH:
Wolfgang Denk4cf26092011-10-07 09:58:21 +02002704 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically
2705 either 0 (32-bit build) or 0xF (36-bit build). This macro is
Timur Tabie46fedf2011-08-04 18:03:41 -05002706 used in assembly code, so it must not contain typecasts or
2707 integer size suffixes (e.g. "ULL").
2708
2709- CONFIG_SYS_CCSRBAR_PHYS_LOW:
2710 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is
2711 used in assembly code, so it must not contain typecasts or
2712 integer size suffixes (e.g. "ULL").
2713
2714- CONFIG_SYS_CCSR_DO_NOT_RELOCATE:
2715 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be
2716 forced to a value that ensures that CCSR is not relocated.
2717
Macpaul Lin0abddf82011-04-11 20:45:32 +00002718- CONFIG_IDE_AHB:
2719 Most IDE controllers were designed to be connected with PCI
2720 interface. Only few of them were designed for AHB interface.
2721 When software is doing ATA command and data transfer to
2722 IDE devices through IDE-AHB controller, some additional
2723 registers accessing to these kind of IDE-AHB controller
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08002724 is required.
Macpaul Lin0abddf82011-04-11 20:45:32 +00002725
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002726- CONFIG_SYS_IMMR: Physical address of the Internal Memory.
wdenkefe2a4d2004-12-16 21:44:03 +00002727 DO NOT CHANGE unless you know exactly what you're
Christophe Leroy907208c2017-07-06 10:23:22 +02002728 doing! (11-4) [MPC8xx systems only]
wdenkc6097192002-11-03 00:24:07 +00002729
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002730- CONFIG_SYS_INIT_RAM_ADDR:
wdenkc6097192002-11-03 00:24:07 +00002731
wdenk7152b1d2003-09-05 23:19:14 +00002732 Start address of memory area that can be used for
wdenkc6097192002-11-03 00:24:07 +00002733 initial data and stack; please note that this must be
2734 writable memory that is working WITHOUT special
2735 initialization, i. e. you CANNOT use normal RAM which
2736 will become available only after programming the
2737 memory controller and running certain initialization
2738 sequences.
2739
2740 U-Boot uses the following memory types:
Christophe Leroy907208c2017-07-06 10:23:22 +02002741 - MPC8xx: IMMR (internal memory of the CPU)
wdenkc6097192002-11-03 00:24:07 +00002742
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002743- CONFIG_SYS_GBL_DATA_OFFSET:
wdenkc6097192002-11-03 00:24:07 +00002744
2745 Offset of the initial data structure in the memory
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002746 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually
2747 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial
wdenkc6097192002-11-03 00:24:07 +00002748 data is located at the end of the available space
Wolfgang Denk553f0982010-10-26 13:32:32 +02002749 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE -
Simon Glassacd51f92016-10-02 18:01:06 -06002750 GENERATED_GBL_DATA_SIZE), and the initial stack is just
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002751 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR +
2752 CONFIG_SYS_GBL_DATA_OFFSET) downward.
wdenkc6097192002-11-03 00:24:07 +00002753
2754 Note:
2755 On the MPC824X (or other systems that use the data
2756 cache for initial memory) the address chosen for
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002757 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must
wdenkc6097192002-11-03 00:24:07 +00002758 point to an otherwise UNUSED address space between
2759 the top of RAM and the start of the PCI space.
2760
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002761- CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27)
wdenkc6097192002-11-03 00:24:07 +00002762
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002763- CONFIG_SYS_OR_TIMING_SDRAM:
wdenkc6097192002-11-03 00:24:07 +00002764 SDRAM timing
2765
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002766- CONFIG_SYS_MAMR_PTA:
wdenkc6097192002-11-03 00:24:07 +00002767 periodic timer for refresh
2768
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002769- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM,
2770 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP,
2771 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM,
2772 CONFIG_SYS_BR1_PRELIM:
wdenkc6097192002-11-03 00:24:07 +00002773 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
2774
2775- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002776 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM,
2777 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM:
wdenkc6097192002-11-03 00:24:07 +00002778 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
2779
Andrew Sharp69fd2d32012-08-29 14:16:32 +00002780- CONFIG_PCI_ENUM_ONLY
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08002781 Only scan through and get the devices on the buses.
Andrew Sharp69fd2d32012-08-29 14:16:32 +00002782 Don't do any setup work, presumably because someone or
2783 something has already done it, and we don't need to do it
2784 a second time. Useful for platforms that are pre-booted
2785 by coreboot or similar.
2786
Gabor Juhos842033e2013-05-30 07:06:12 +00002787- CONFIG_PCI_INDIRECT_BRIDGE:
2788 Enable support for indirect PCI bridges.
2789
Kumar Galaa09b9b62010-12-30 12:09:53 -06002790- CONFIG_SYS_SRIO:
2791 Chip has SRIO or not
2792
2793- CONFIG_SRIO1:
2794 Board has SRIO 1 port available
2795
2796- CONFIG_SRIO2:
2797 Board has SRIO 2 port available
2798
Liu Gangc8b28152013-05-07 16:30:46 +08002799- CONFIG_SRIO_PCIE_BOOT_MASTER
2800 Board can support master function for Boot from SRIO and PCIE
2801
Kumar Galaa09b9b62010-12-30 12:09:53 -06002802- CONFIG_SYS_SRIOn_MEM_VIRT:
2803 Virtual Address of SRIO port 'n' memory region
2804
Simon Glass62f9b652019-11-14 12:57:09 -07002805- CONFIG_SYS_SRIOn_MEM_PHYxS:
Kumar Galaa09b9b62010-12-30 12:09:53 -06002806 Physical Address of SRIO port 'n' memory region
2807
2808- CONFIG_SYS_SRIOn_MEM_SIZE:
2809 Size of SRIO port 'n' memory region
2810
Fabio Estevam66bd1842013-04-11 09:35:34 +00002811- CONFIG_SYS_NAND_BUSWIDTH_16BIT
2812 Defined to tell the NAND controller that the NAND chip is using
2813 a 16 bit bus.
2814 Not all NAND drivers use this symbol.
Fabio Estevama430e912013-04-11 09:35:35 +00002815 Example of drivers that use it:
Miquel Raynala430fa02018-08-16 17:30:07 +02002816 - drivers/mtd/nand/raw/ndfc.c
2817 - drivers/mtd/nand/raw/mxc_nand.c
Alex Watermaneced4622011-05-19 15:08:36 -04002818
2819- CONFIG_SYS_NDFC_EBC0_CFG
2820 Sets the EBC0_CFG register for the NDFC. If not defined
2821 a default value will be used.
2822
Ben Warrenbb99ad62006-09-07 16:50:54 -04002823- CONFIG_SPD_EEPROM
Wolfgang Denk218ca722008-03-26 10:40:12 +01002824 Get DDR timing information from an I2C EEPROM. Common
2825 with pluggable memory modules such as SODIMMs
2826
Ben Warrenbb99ad62006-09-07 16:50:54 -04002827 SPD_EEPROM_ADDRESS
2828 I2C address of the SPD EEPROM
2829
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002830- CONFIG_SYS_SPD_BUS_NUM
Wolfgang Denk218ca722008-03-26 10:40:12 +01002831 If SPD EEPROM is on an I2C bus other than the first
2832 one, specify here. Note that the value must resolve
2833 to something your driver can deal with.
Ben Warrenbb99ad62006-09-07 16:50:54 -04002834
York Sun1b3e3c42011-06-07 09:42:16 +08002835- CONFIG_SYS_DDR_RAW_TIMING
2836 Get DDR timing information from other than SPD. Common with
2837 soldered DDR chips onboard without SPD. DDR raw timing
2838 parameters are extracted from datasheet and hard-coded into
2839 header files or board specific files.
2840
York Sun6f5e1dc2011-09-16 13:21:35 -07002841- CONFIG_FSL_DDR_INTERACTIVE
2842 Enable interactive DDR debugging. See doc/README.fsl-ddr.
2843
York Sune32d59a2015-01-06 13:18:55 -08002844- CONFIG_FSL_DDR_SYNC_REFRESH
2845 Enable sync of refresh for multiple controllers.
2846
York Sun4516ff82015-03-19 09:30:28 -07002847- CONFIG_FSL_DDR_BIST
2848 Enable built-in memory test for Freescale DDR controllers.
2849
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002850- CONFIG_SYS_83XX_DDR_USES_CS0
Wolfgang Denk218ca722008-03-26 10:40:12 +01002851 Only for 83xx systems. If specified, then DDR should
2852 be configured using CS0 and CS1 instead of CS2 and CS3.
Timur Tabi2ad6b512006-10-31 18:44:42 -06002853
wdenkc26e4542004-04-18 10:13:26 +00002854- CONFIG_RMII
2855 Enable RMII mode for all FECs.
2856 Note that this is a global option, we can't
2857 have one FEC in standard MII mode and another in RMII mode.
2858
wdenk5cf91d62004-04-23 20:32:05 +00002859- CONFIG_CRC32_VERIFY
2860 Add a verify option to the crc32 command.
2861 The syntax is:
2862
2863 => crc32 -v <address> <count> <crc32>
2864
2865 Where address/count indicate a memory area
2866 and crc32 is the correct crc32 which the
2867 area should have.
2868
wdenk56523f12004-07-11 17:40:54 +00002869- CONFIG_LOOPW
2870 Add the "loopw" memory command. This only takes effect if
Simon Glass493f4202017-08-04 16:34:27 -06002871 the memory commands are activated globally (CONFIG_CMD_MEMORY).
wdenk56523f12004-07-11 17:40:54 +00002872
Joel Johnson72732312020-01-29 09:17:18 -07002873- CONFIG_CMD_MX_CYCLIC
stroese7b466642004-12-16 18:46:55 +00002874 Add the "mdc" and "mwc" memory commands. These are cyclic
2875 "md/mw" commands.
2876 Examples:
2877
wdenkefe2a4d2004-12-16 21:44:03 +00002878 => mdc.b 10 4 500
stroese7b466642004-12-16 18:46:55 +00002879 This command will print 4 bytes (10,11,12,13) each 500 ms.
2880
wdenkefe2a4d2004-12-16 21:44:03 +00002881 => mwc.l 100 12345678 10
stroese7b466642004-12-16 18:46:55 +00002882 This command will write 12345678 to address 100 all 10 ms.
2883
wdenkefe2a4d2004-12-16 21:44:03 +00002884 This only takes effect if the memory commands are activated
Simon Glass493f4202017-08-04 16:34:27 -06002885 globally (CONFIG_CMD_MEMORY).
stroese7b466642004-12-16 18:46:55 +00002886
wdenk8aa1a2d2005-04-04 12:44:11 +00002887- CONFIG_SKIP_LOWLEVEL_INIT
Rick Chen3fafced2017-12-26 13:55:59 +08002888 [ARM, NDS32, MIPS, RISC-V only] If this variable is defined, then certain
Wolfgang Denk844f07d2010-11-27 23:30:56 +01002889 low level initializations (like setting up the memory
2890 controller) are omitted and/or U-Boot does not
2891 relocate itself into RAM.
wdenk8aa1a2d2005-04-04 12:44:11 +00002892
Wolfgang Denk844f07d2010-11-27 23:30:56 +01002893 Normally this variable MUST NOT be defined. The only
2894 exception is when U-Boot is loaded (to RAM) by some
2895 other boot loader or by a debugger which performs
2896 these initializations itself.
wdenk8aa1a2d2005-04-04 12:44:11 +00002897
Simon Glassb5bd0982016-05-05 07:28:06 -06002898- CONFIG_SKIP_LOWLEVEL_INIT_ONLY
2899 [ARM926EJ-S only] This allows just the call to lowlevel_init()
yeongjun Kim90211f72016-07-20 22:56:12 +09002900 to be skipped. The normal CP15 init (such as enabling the
Simon Glassb5bd0982016-05-05 07:28:06 -06002901 instruction cache) is still performed.
2902
Aneesh V401bb302011-07-13 05:11:07 +00002903- CONFIG_SPL_BUILD
Thomas Hebb32f2ca22019-11-13 18:18:03 -08002904 Set when the currently-running compilation is for an artifact
2905 that will end up in the SPL (as opposed to the TPL or U-Boot
2906 proper). Code that needs stage-specific behavior should check
2907 this.
wdenk400558b2005-04-02 23:52:25 +00002908
Ying Zhang3aa29de2013-08-16 15:16:15 +08002909- CONFIG_TPL_BUILD
Thomas Hebb32f2ca22019-11-13 18:18:03 -08002910 Set when the currently-running compilation is for an artifact
2911 that will end up in the TPL (as opposed to the SPL or U-Boot
2912 proper). Code that needs stage-specific behavior should check
2913 this.
Ying Zhang3aa29de2013-08-16 15:16:15 +08002914
Ying Zhang5df572f2013-05-20 14:07:23 +08002915- CONFIG_SYS_MPC85XX_NO_RESETVEC
2916 Only for 85xx systems. If this variable is specified, the section
2917 .resetvec is not kept and the section .bootpg is placed in the
2918 previous 4k of the .text section.
2919
Simon Glass4213fc22013-02-24 17:33:14 +00002920- CONFIG_ARCH_MAP_SYSMEM
2921 Generally U-Boot (and in particular the md command) uses
2922 effective address. It is therefore not necessary to regard
2923 U-Boot address as virtual addresses that need to be translated
2924 to physical addresses. However, sandbox requires this, since
2925 it maintains its own little RAM buffer which contains all
2926 addressable memory. This option causes some memory accesses
2927 to be mapped through map_sysmem() / unmap_sysmem().
2928
Simon Glass588a13f2013-02-14 04:18:54 +00002929- CONFIG_X86_RESET_VECTOR
2930 If defined, the x86 reset vector code is included. This is not
2931 needed when U-Boot is running from Coreboot.
Gabe Blackb16f5212012-11-27 21:08:06 +00002932
Karicheri, Muralidharan999d7d32014-04-04 13:16:50 -04002933- CONFIG_SYS_NAND_NO_SUBPAGE_WRITE
2934 Option to disable subpage write in NAND driver
2935 driver that uses this:
Miquel Raynala430fa02018-08-16 17:30:07 +02002936 drivers/mtd/nand/raw/davinci_nand.c
Karicheri, Muralidharan999d7d32014-04-04 13:16:50 -04002937
Timur Tabif2717b42011-11-22 09:21:25 -06002938Freescale QE/FMAN Firmware Support:
2939-----------------------------------
2940
2941The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the
2942loading of "firmware", which is encoded in the QE firmware binary format.
2943This firmware often needs to be loaded during U-Boot booting, so macros
2944are used to identify the storage device (NOR flash, SPI, etc) and the address
2945within that device.
2946
Zhao Qiangdcf1d772014-03-21 16:21:44 +08002947- CONFIG_SYS_FMAN_FW_ADDR
2948 The address in the storage device where the FMAN microcode is located. The
Tom Rinicc1e98b2019-05-12 07:59:12 -04002949 meaning of this address depends on which CONFIG_SYS_QE_FMAN_FW_IN_xxx macro
Zhao Qiangdcf1d772014-03-21 16:21:44 +08002950 is also specified.
2951
2952- CONFIG_SYS_QE_FW_ADDR
2953 The address in the storage device where the QE microcode is located. The
Tom Rinicc1e98b2019-05-12 07:59:12 -04002954 meaning of this address depends on which CONFIG_SYS_QE_FMAN_FW_IN_xxx macro
Timur Tabif2717b42011-11-22 09:21:25 -06002955 is also specified.
2956
2957- CONFIG_SYS_QE_FMAN_FW_LENGTH
2958 The maximum possible size of the firmware. The firmware binary format
2959 has a field that specifies the actual size of the firmware, but it
2960 might not be possible to read any part of the firmware unless some
2961 local storage is allocated to hold the entire firmware first.
2962
2963- CONFIG_SYS_QE_FMAN_FW_IN_NOR
2964 Specifies that QE/FMAN firmware is located in NOR flash, mapped as
2965 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the
2966 virtual address in NOR flash.
2967
2968- CONFIG_SYS_QE_FMAN_FW_IN_NAND
2969 Specifies that QE/FMAN firmware is located in NAND flash.
2970 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash.
2971
2972- CONFIG_SYS_QE_FMAN_FW_IN_MMC
2973 Specifies that QE/FMAN firmware is located on the primary SD/MMC
2974 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
2975
Liu Gang292dc6c2012-03-08 00:33:18 +00002976- CONFIG_SYS_QE_FMAN_FW_IN_REMOTE
2977 Specifies that QE/FMAN firmware is located in the remote (master)
2978 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which
Liu Gangfc54c7f2012-08-09 05:10:01 +00002979 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound
2980 window->master inbound window->master LAW->the ucode address in
2981 master's memory space.
Timur Tabif2717b42011-11-22 09:21:25 -06002982
J. German Riverab940ca62014-06-23 15:15:55 -07002983Freescale Layerscape Management Complex Firmware Support:
2984---------------------------------------------------------
2985The Freescale Layerscape Management Complex (MC) supports the loading of
2986"firmware".
2987This firmware often needs to be loaded during U-Boot booting, so macros
2988are used to identify the storage device (NOR flash, SPI, etc) and the address
2989within that device.
2990
2991- CONFIG_FSL_MC_ENET
2992 Enable the MC driver for Layerscape SoCs.
2993
Prabhakar Kushwaha5c055082015-06-02 10:55:52 +05302994Freescale Layerscape Debug Server Support:
2995-------------------------------------------
2996The Freescale Layerscape Debug Server Support supports the loading of
2997"Debug Server firmware" and triggering SP boot-rom.
2998This firmware often needs to be loaded during U-Boot booting.
2999
York Sunc0492142015-12-07 11:08:58 -08003000- CONFIG_SYS_MC_RSV_MEM_ALIGN
3001 Define alignment of reserved memory MC requires
Prabhakar Kushwaha5c055082015-06-02 10:55:52 +05303002
Paul Kocialkowskif3f431a2015-07-26 18:48:15 +02003003Reproducible builds
3004-------------------
3005
3006In order to achieve reproducible builds, timestamps used in the U-Boot build
3007process have to be set to a fixed value.
3008
3009This is done using the SOURCE_DATE_EPOCH environment variable.
3010SOURCE_DATE_EPOCH is to be set on the build host's shell, not as a configuration
3011option for U-Boot or an environment variable in U-Boot.
3012
3013SOURCE_DATE_EPOCH should be set to a number of seconds since the epoch, in UTC.
3014
wdenkc6097192002-11-03 00:24:07 +00003015Building the Software:
3016======================
3017
Wolfgang Denk218ca722008-03-26 10:40:12 +01003018Building U-Boot has been tested in several native build environments
3019and in many different cross environments. Of course we cannot support
3020all possibly existing versions of cross development tools in all
3021(potentially obsolete) versions. In case of tool chain problems we
Naoki Hayama047f6ec2020-10-08 13:17:16 +09003022recommend to use the ELDK (see https://www.denx.de/wiki/DULG/ELDK)
Wolfgang Denk218ca722008-03-26 10:40:12 +01003023which is extensively used to build and test U-Boot.
wdenkc6097192002-11-03 00:24:07 +00003024
Wolfgang Denk218ca722008-03-26 10:40:12 +01003025If you are not using a native environment, it is assumed that you
3026have GNU cross compiling tools available in your path. In this case,
3027you must set the environment variable CROSS_COMPILE in your shell.
3028Note that no changes to the Makefile or any other source files are
3029necessary. For example using the ELDK on a 4xx CPU, please enter:
wdenkc6097192002-11-03 00:24:07 +00003030
Wolfgang Denk218ca722008-03-26 10:40:12 +01003031 $ CROSS_COMPILE=ppc_4xx-
3032 $ export CROSS_COMPILE
wdenkc6097192002-11-03 00:24:07 +00003033
Wolfgang Denk218ca722008-03-26 10:40:12 +01003034U-Boot is intended to be simple to build. After installing the
3035sources you must configure U-Boot for one specific board type. This
wdenkc6097192002-11-03 00:24:07 +00003036is done by typing:
3037
Holger Freytherab584d62014-08-04 09:26:05 +02003038 make NAME_defconfig
wdenkc6097192002-11-03 00:24:07 +00003039
Holger Freytherab584d62014-08-04 09:26:05 +02003040where "NAME_defconfig" is the name of one of the existing configu-
Heinrich Schuchardtecb3a0a2020-02-24 18:36:30 +01003041rations; see configs/*_defconfig for supported names.
wdenk54387ac2003-10-08 22:45:44 +00003042
Heinrich Schuchardtecb3a0a2020-02-24 18:36:30 +01003043Note: for some boards special configuration names may exist; check if
wdenk2729af92004-05-03 20:45:30 +00003044 additional information is available from the board vendor; for
3045 instance, the TQM823L systems are available without (standard)
3046 or with LCD support. You can select such additional "features"
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02003047 when choosing the configuration, i. e.
wdenkc6097192002-11-03 00:24:07 +00003048
Holger Freytherab584d62014-08-04 09:26:05 +02003049 make TQM823L_defconfig
wdenk2729af92004-05-03 20:45:30 +00003050 - will configure for a plain TQM823L, i. e. no LCD support
wdenkc6097192002-11-03 00:24:07 +00003051
Holger Freytherab584d62014-08-04 09:26:05 +02003052 make TQM823L_LCD_defconfig
wdenk2729af92004-05-03 20:45:30 +00003053 - will configure for a TQM823L with U-Boot console on LCD
wdenkc6097192002-11-03 00:24:07 +00003054
wdenk2729af92004-05-03 20:45:30 +00003055 etc.
wdenkc6097192002-11-03 00:24:07 +00003056
wdenkc6097192002-11-03 00:24:07 +00003057
wdenk2729af92004-05-03 20:45:30 +00003058Finally, type "make all", and you should get some working U-Boot
3059images ready for download to / installation on your system:
wdenkc6097192002-11-03 00:24:07 +00003060
wdenk2729af92004-05-03 20:45:30 +00003061- "u-boot.bin" is a raw binary image
3062- "u-boot" is an image in ELF binary format
3063- "u-boot.srec" is in Motorola S-Record format
wdenkc6097192002-11-03 00:24:07 +00003064
Marian Balakowiczbaf31242006-09-07 17:25:40 +02003065By default the build is performed locally and the objects are saved
3066in the source directory. One of the two methods can be used to change
3067this behavior and build U-Boot to some external directory:
3068
30691. Add O= to the make command line invocations:
3070
3071 make O=/tmp/build distclean
Holger Freytherab584d62014-08-04 09:26:05 +02003072 make O=/tmp/build NAME_defconfig
Marian Balakowiczbaf31242006-09-07 17:25:40 +02003073 make O=/tmp/build all
3074
Timo Ketolaadbba992014-11-06 14:39:05 +020030752. Set environment variable KBUILD_OUTPUT to point to the desired location:
Marian Balakowiczbaf31242006-09-07 17:25:40 +02003076
Timo Ketolaadbba992014-11-06 14:39:05 +02003077 export KBUILD_OUTPUT=/tmp/build
Marian Balakowiczbaf31242006-09-07 17:25:40 +02003078 make distclean
Holger Freytherab584d62014-08-04 09:26:05 +02003079 make NAME_defconfig
Marian Balakowiczbaf31242006-09-07 17:25:40 +02003080 make all
3081
Timo Ketolaadbba992014-11-06 14:39:05 +02003082Note that the command line "O=" setting overrides the KBUILD_OUTPUT environment
Marian Balakowiczbaf31242006-09-07 17:25:40 +02003083variable.
3084
Daniel Schwierzeck215bb1c2018-01-26 16:31:04 +01003085User specific CPPFLAGS, AFLAGS and CFLAGS can be passed to the compiler by
3086setting the according environment variables KCPPFLAGS, KAFLAGS and KCFLAGS.
3087For example to treat all compiler warnings as errors:
3088
3089 make KCFLAGS=-Werror
wdenkc6097192002-11-03 00:24:07 +00003090
wdenk2729af92004-05-03 20:45:30 +00003091Please be aware that the Makefiles assume you are using GNU make, so
3092for instance on NetBSD you might need to use "gmake" instead of
3093native "make".
wdenkc6097192002-11-03 00:24:07 +00003094
wdenkc6097192002-11-03 00:24:07 +00003095
wdenk2729af92004-05-03 20:45:30 +00003096If the system board that you have is not listed, then you will need
3097to port U-Boot to your hardware platform. To do this, follow these
3098steps:
wdenkc6097192002-11-03 00:24:07 +00003099
Phil Sutter3c1496c2015-12-25 14:41:18 +010031001. Create a new directory to hold your board specific code. Add any
wdenk2729af92004-05-03 20:45:30 +00003101 files you need. In your board directory, you will need at least
Phil Sutter3c1496c2015-12-25 14:41:18 +01003102 the "Makefile" and a "<board>.c".
31032. Create a new configuration file "include/configs/<board>.h" for
3104 your board.
wdenk2729af92004-05-03 20:45:30 +000031053. If you're porting U-Boot to a new CPU, then also create a new
3106 directory to hold your CPU specific code. Add any files you need.
Holger Freytherab584d62014-08-04 09:26:05 +020031074. Run "make <board>_defconfig" with your new name.
wdenk2729af92004-05-03 20:45:30 +000031085. Type "make", and you should get a working "u-boot.srec" file
3109 to be installed on your target system.
31106. Debug and solve any problems that might arise.
3111 [Of course, this last step is much harder than it sounds.]
wdenkc6097192002-11-03 00:24:07 +00003112
wdenkc6097192002-11-03 00:24:07 +00003113
wdenk2729af92004-05-03 20:45:30 +00003114Testing of U-Boot Modifications, Ports to New Hardware, etc.:
3115==============================================================
wdenkc6097192002-11-03 00:24:07 +00003116
Wolfgang Denk218ca722008-03-26 10:40:12 +01003117If you have modified U-Boot sources (for instance added a new board
3118or support for new devices, a new CPU, etc.) you are expected to
wdenk2729af92004-05-03 20:45:30 +00003119provide feedback to the other developers. The feedback normally takes
Thomas Hebb32f2ca22019-11-13 18:18:03 -08003120the form of a "patch", i.e. a context diff against a certain (latest
Wolfgang Denk218ca722008-03-26 10:40:12 +01003121official or latest in the git repository) version of U-Boot sources.
wdenkc6097192002-11-03 00:24:07 +00003122
Wolfgang Denk218ca722008-03-26 10:40:12 +01003123But before you submit such a patch, please verify that your modifi-
3124cation did not break existing code. At least make sure that *ALL* of
wdenk2729af92004-05-03 20:45:30 +00003125the supported boards compile WITHOUT ANY compiler warnings. To do so,
Simon Glass6de80f22016-07-27 20:33:08 -06003126just run the buildman script (tools/buildman/buildman), which will
3127configure and build U-Boot for ALL supported system. Be warned, this
3128will take a while. Please see the buildman README, or run 'buildman -H'
3129for documentation.
Marian Balakowiczbaf31242006-09-07 17:25:40 +02003130
3131
wdenk2729af92004-05-03 20:45:30 +00003132See also "U-Boot Porting Guide" below.
wdenkc6097192002-11-03 00:24:07 +00003133
wdenkc6097192002-11-03 00:24:07 +00003134
wdenk2729af92004-05-03 20:45:30 +00003135Monitor Commands - Overview:
3136============================
wdenkc6097192002-11-03 00:24:07 +00003137
wdenk2729af92004-05-03 20:45:30 +00003138go - start application at address 'addr'
3139run - run commands in an environment variable
3140bootm - boot application image from memory
3141bootp - boot image via network using BootP/TFTP protocol
Marek Vasut44f074c2012-03-14 21:52:45 +00003142bootz - boot zImage from memory
wdenk2729af92004-05-03 20:45:30 +00003143tftpboot- boot image via network using TFTP protocol
3144 and env variables "ipaddr" and "serverip"
3145 (and eventually "gatewayip")
Simon Glass1fb7cd42011-10-24 18:00:07 +00003146tftpput - upload a file via network using TFTP protocol
wdenk2729af92004-05-03 20:45:30 +00003147rarpboot- boot image via network using RARP/TFTP protocol
3148diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
3149loads - load S-Record file over serial line
3150loadb - load binary file over serial line (kermit mode)
3151md - memory display
3152mm - memory modify (auto-incrementing)
3153nm - memory modify (constant address)
3154mw - memory write (fill)
Simon Glassbdded202020-06-02 19:26:49 -06003155ms - memory search
wdenk2729af92004-05-03 20:45:30 +00003156cp - memory copy
3157cmp - memory compare
3158crc32 - checksum calculation
Peter Tyser0f89c542009-04-18 22:34:03 -05003159i2c - I2C sub-system
wdenk2729af92004-05-03 20:45:30 +00003160sspi - SPI utility commands
3161base - print or set address offset
3162printenv- print environment variables
3163setenv - set environment variables
3164saveenv - save environment variables to persistent storage
3165protect - enable or disable FLASH write protection
3166erase - erase FLASH memory
3167flinfo - print FLASH memory information
Karl O. Pinc10635af2012-08-03 05:57:21 +00003168nand - NAND memory operations (see doc/README.nand)
wdenk2729af92004-05-03 20:45:30 +00003169bdinfo - print Board Info structure
3170iminfo - print header information for application image
3171coninfo - print console devices and informations
3172ide - IDE sub-system
3173loop - infinite loop on address range
wdenk56523f12004-07-11 17:40:54 +00003174loopw - infinite write loop on address range
wdenk2729af92004-05-03 20:45:30 +00003175mtest - simple RAM test
3176icache - enable or disable instruction cache
3177dcache - enable or disable data cache
3178reset - Perform RESET of the CPU
3179echo - echo args to console
3180version - print monitor version
3181help - print online help
3182? - alias for 'help'
wdenkc6097192002-11-03 00:24:07 +00003183
wdenkc6097192002-11-03 00:24:07 +00003184
wdenk2729af92004-05-03 20:45:30 +00003185Monitor Commands - Detailed Description:
3186========================================
wdenkc6097192002-11-03 00:24:07 +00003187
wdenk2729af92004-05-03 20:45:30 +00003188TODO.
wdenkc6097192002-11-03 00:24:07 +00003189
wdenk2729af92004-05-03 20:45:30 +00003190For now: just type "help <command>".
wdenkc6097192002-11-03 00:24:07 +00003191
3192
wdenk2729af92004-05-03 20:45:30 +00003193Environment Variables:
3194======================
wdenkc6097192002-11-03 00:24:07 +00003195
wdenk2729af92004-05-03 20:45:30 +00003196U-Boot supports user configuration using Environment Variables which
3197can be made persistent by saving to Flash memory.
wdenkc6097192002-11-03 00:24:07 +00003198
wdenk2729af92004-05-03 20:45:30 +00003199Environment Variables are set using "setenv", printed using
3200"printenv", and saved to Flash using "saveenv". Using "setenv"
3201without a value can be used to delete a variable from the
3202environment. As long as you don't save the environment you are
3203working with an in-memory copy. In case the Flash area containing the
3204environment is erased by accident, a default environment is provided.
wdenkc6097192002-11-03 00:24:07 +00003205
Wolfgang Denkc96f86e2010-01-17 23:55:53 +01003206Some configuration options can be set using Environment Variables.
3207
3208List of environment variables (most likely not complete):
wdenkc6097192002-11-03 00:24:07 +00003209
wdenk2729af92004-05-03 20:45:30 +00003210 baudrate - see CONFIG_BAUDRATE
wdenkc6097192002-11-03 00:24:07 +00003211
wdenk2729af92004-05-03 20:45:30 +00003212 bootdelay - see CONFIG_BOOTDELAY
wdenkc6097192002-11-03 00:24:07 +00003213
wdenk2729af92004-05-03 20:45:30 +00003214 bootcmd - see CONFIG_BOOTCOMMAND
wdenkc6097192002-11-03 00:24:07 +00003215
wdenk2729af92004-05-03 20:45:30 +00003216 bootargs - Boot arguments when booting an RTOS image
wdenkc6097192002-11-03 00:24:07 +00003217
wdenk2729af92004-05-03 20:45:30 +00003218 bootfile - Name of the image to load with TFTP
wdenkc6097192002-11-03 00:24:07 +00003219
Bartlomiej Sieka7d721e32008-04-14 15:44:16 +02003220 bootm_low - Memory range available for image processing in the bootm
3221 command can be restricted. This variable is given as
3222 a hexadecimal number and defines lowest address allowed
3223 for use by the bootm command. See also "bootm_size"
3224 environment variable. Address defined by "bootm_low" is
3225 also the base of the initial memory mapping for the Linux
Grant Likelyc3624e62011-03-28 09:58:43 +00003226 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and
3227 bootm_mapsize.
3228
Wolfgang Denkc0f40852011-10-26 10:21:21 +00003229 bootm_mapsize - Size of the initial memory mapping for the Linux kernel.
Grant Likelyc3624e62011-03-28 09:58:43 +00003230 This variable is given as a hexadecimal number and it
3231 defines the size of the memory region starting at base
3232 address bootm_low that is accessible by the Linux kernel
3233 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used
3234 as the default value if it is defined, and bootm_size is
3235 used otherwise.
Bartlomiej Sieka7d721e32008-04-14 15:44:16 +02003236
3237 bootm_size - Memory range available for image processing in the bootm
3238 command can be restricted. This variable is given as
3239 a hexadecimal number and defines the size of the region
3240 allowed for use by the bootm command. See also "bootm_low"
3241 environment variable.
3242
Simon Glass88fa4be2019-07-20 20:51:17 -06003243 bootstopkeysha256, bootdelaykey, bootstopkey - See README.autoboot
3244
Bartlomiej Sieka4bae9092008-10-01 15:26:31 +02003245 updatefile - Location of the software update file on a TFTP server, used
3246 by the automatic software update feature. Please refer to
3247 documentation in doc/README.update for more details.
3248
wdenk2729af92004-05-03 20:45:30 +00003249 autoload - if set to "no" (any string beginning with 'n'),
3250 "bootp" will just load perform a lookup of the
3251 configuration from the BOOTP server, but not try to
3252 load any image using TFTP
wdenkc6097192002-11-03 00:24:07 +00003253
wdenk2729af92004-05-03 20:45:30 +00003254 autostart - if set to "yes", an image loaded using the "bootp",
3255 "rarpboot", "tftpboot" or "diskboot" commands will
3256 be automatically started (by internally calling
3257 "bootm")
wdenkc6097192002-11-03 00:24:07 +00003258
wdenk2729af92004-05-03 20:45:30 +00003259 If set to "no", a standalone image passed to the
3260 "bootm" command will be copied to the load address
3261 (and eventually uncompressed), but NOT be started.
3262 This can be used to load and uncompress arbitrary
3263 data.
wdenkc6097192002-11-03 00:24:07 +00003264
David A. Longa28afca2011-07-09 16:40:19 -04003265 fdt_high - if set this restricts the maximum address that the
3266 flattened device tree will be copied into upon boot.
Shawn Guofa34f6b2012-01-09 21:54:08 +00003267 For example, if you have a system with 1 GB memory
3268 at physical address 0x10000000, while Linux kernel
3269 only recognizes the first 704 MB as low memory, you
3270 may need to set fdt_high as 0x3C000000 to have the
3271 device tree blob be copied to the maximum address
3272 of the 704 MB low memory, so that Linux kernel can
3273 access it during the boot procedure.
3274
David A. Longa28afca2011-07-09 16:40:19 -04003275 If this is set to the special value 0xFFFFFFFF then
3276 the fdt will not be copied at all on boot. For this
3277 to work it must reside in writable memory, have
3278 sufficient padding on the end of it for u-boot to
3279 add the information it needs into it, and the memory
3280 must be accessible by the kernel.
3281
Simon Glasseea63e02011-10-24 19:15:34 +00003282 fdtcontroladdr- if set this is the address of the control flattened
3283 device tree used by U-Boot when CONFIG_OF_CONTROL is
3284 defined.
3285
wdenk17ea1172004-06-06 21:51:03 +00003286 i2cfast - (PPC405GP|PPC405EP only)
3287 if set to 'y' configures Linux I2C driver for fast
3288 mode (400kHZ). This environment variable is used in
3289 initialization code. So, for changes to be effective
3290 it must be saved and board must be reset.
3291
wdenk2729af92004-05-03 20:45:30 +00003292 initrd_high - restrict positioning of initrd images:
3293 If this variable is not set, initrd images will be
3294 copied to the highest possible address in RAM; this
3295 is usually what you want since it allows for
3296 maximum initrd size. If for some reason you want to
3297 make sure that the initrd image is loaded below the
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003298 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment
wdenk2729af92004-05-03 20:45:30 +00003299 variable to a value of "no" or "off" or "0".
3300 Alternatively, you can set it to a maximum upper
3301 address to use (U-Boot will still check that it
3302 does not overwrite the U-Boot stack and data).
wdenkc6097192002-11-03 00:24:07 +00003303
wdenk2729af92004-05-03 20:45:30 +00003304 For instance, when you have a system with 16 MB
3305 RAM, and want to reserve 4 MB from use by Linux,
3306 you can do this by adding "mem=12M" to the value of
3307 the "bootargs" variable. However, now you must make
3308 sure that the initrd image is placed in the first
3309 12 MB as well - this can be done with
wdenkc6097192002-11-03 00:24:07 +00003310
wdenk2729af92004-05-03 20:45:30 +00003311 setenv initrd_high 00c00000
wdenkc6097192002-11-03 00:24:07 +00003312
wdenk2729af92004-05-03 20:45:30 +00003313 If you set initrd_high to 0xFFFFFFFF, this is an
3314 indication to U-Boot that all addresses are legal
3315 for the Linux kernel, including addresses in flash
3316 memory. In this case U-Boot will NOT COPY the
3317 ramdisk at all. This may be useful to reduce the
3318 boot time on your system, but requires that this
3319 feature is supported by your Linux kernel.
wdenk4a6fd342003-04-12 23:38:12 +00003320
wdenk2729af92004-05-03 20:45:30 +00003321 ipaddr - IP address; needed for tftpboot command
wdenkc6097192002-11-03 00:24:07 +00003322
wdenk2729af92004-05-03 20:45:30 +00003323 loadaddr - Default load address for commands like "bootp",
3324 "rarpboot", "tftpboot", "loadb" or "diskboot"
wdenkc6097192002-11-03 00:24:07 +00003325
wdenk2729af92004-05-03 20:45:30 +00003326 loads_echo - see CONFIG_LOADS_ECHO
wdenkc6097192002-11-03 00:24:07 +00003327
wdenk2729af92004-05-03 20:45:30 +00003328 serverip - TFTP server IP address; needed for tftpboot command
wdenk38b99262003-05-23 23:18:21 +00003329
wdenk2729af92004-05-03 20:45:30 +00003330 bootretry - see CONFIG_BOOT_RETRY_TIME
wdenkc6097192002-11-03 00:24:07 +00003331
wdenk2729af92004-05-03 20:45:30 +00003332 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
wdenkc6097192002-11-03 00:24:07 +00003333
wdenk2729af92004-05-03 20:45:30 +00003334 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
wdenkc6097192002-11-03 00:24:07 +00003335
Mike Frysingere2a53452011-10-02 10:01:27 +00003336 ethprime - controls which interface is used first.
wdenkc6097192002-11-03 00:24:07 +00003337
Mike Frysingere2a53452011-10-02 10:01:27 +00003338 ethact - controls which interface is currently active.
3339 For example you can do the following
wdenkc6097192002-11-03 00:24:07 +00003340
Heiko Schocher48690d82010-07-20 17:45:02 +02003341 => setenv ethact FEC
3342 => ping 192.168.0.1 # traffic sent on FEC
3343 => setenv ethact SCC
3344 => ping 10.0.0.1 # traffic sent on SCC
wdenkc6097192002-11-03 00:24:07 +00003345
Matthias Fuchse1692572008-01-17 07:45:05 +01003346 ethrotate - When set to "no" U-Boot does not go through all
3347 available network interfaces.
3348 It just stays at the currently selected interface.
3349
Wolfgang Denkc96f86e2010-01-17 23:55:53 +01003350 netretry - When set to "no" each network operation will
wdenk2729af92004-05-03 20:45:30 +00003351 either succeed or fail without retrying.
3352 When set to "once" the network operation will
3353 fail when all the available network interfaces
3354 are tried once without success.
3355 Useful on scripts which control the retry operation
3356 themselves.
wdenkc6097192002-11-03 00:24:07 +00003357
Jean-Christophe PLAGNIOL-VILLARDb4e2f892009-01-31 09:53:39 +01003358 npe_ucode - set load address for the NPE microcode
Jean-Christophe PLAGNIOL-VILLARDa1cf0272008-01-07 08:41:34 +01003359
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08003360 silent_linux - If set then Linux will be told to boot silently, by
Simon Glass8d51aac2013-07-16 20:10:00 -07003361 changing the console to be empty. If "yes" it will be
3362 made silent. If "no" it will not be made silent. If
3363 unset, then it will be made silent if the U-Boot console
3364 is silent.
3365
Albert ARIBAUD \(3ADEV\)f5fb7342015-10-12 00:02:57 +02003366 tftpsrcp - If this is set, the value is used for TFTP's
Wolfgang Denkecb0ccd2005-09-24 22:37:32 +02003367 UDP source port.
3368
Albert ARIBAUD \(3ADEV\)f5fb7342015-10-12 00:02:57 +02003369 tftpdstp - If this is set, the value is used for TFTP's UDP
Wolfgang Denk28cb9372005-09-24 23:25:46 +02003370 destination port instead of the Well Know Port 69.
3371
Wolfgang Denkc96f86e2010-01-17 23:55:53 +01003372 tftpblocksize - Block size to use for TFTP transfers; if not set,
3373 we use the TFTP server's default block size
3374
3375 tftptimeout - Retransmission timeout for TFTP packets (in milli-
3376 seconds, minimum value is 1000 = 1 second). Defines
3377 when a packet is considered to be lost so it has to
3378 be retransmitted. The default is 5000 = 5 seconds.
3379 Lowering this value may make downloads succeed
3380 faster in networks with high packet loss rates or
3381 with unreliable TFTP servers.
3382
Albert ARIBAUD \(3ADEV\)f5fb7342015-10-12 00:02:57 +02003383 tftptimeoutcountmax - maximum count of TFTP timeouts (no
3384 unit, minimum value = 0). Defines how many timeouts
3385 can happen during a single file transfer before that
3386 transfer is aborted. The default is 10, and 0 means
3387 'no timeouts allowed'. Increasing this value may help
3388 downloads succeed with high packet loss rates, or with
3389 unreliable TFTP servers or client hardware.
3390
Ramon Friedcc6b87e2020-07-18 23:31:46 +03003391 tftpwindowsize - if this is set, the value is used for TFTP's
3392 window size as described by RFC 7440.
3393 This means the count of blocks we can receive before
3394 sending ack to server.
3395
Wolfgang Denkc96f86e2010-01-17 23:55:53 +01003396 vlan - When set to a value < 4095 the traffic over
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02003397 Ethernet is encapsulated/received over 802.1q
wdenk2729af92004-05-03 20:45:30 +00003398 VLAN tagged frames.
wdenka3d991b2004-04-15 21:48:45 +00003399
Alexandre Messier50768f52016-02-01 17:08:57 -05003400 bootpretryperiod - Period during which BOOTP/DHCP sends retries.
3401 Unsigned value, in milliseconds. If not set, the period will
3402 be either the default (28000), or a value based on
3403 CONFIG_NET_RETRY_COUNT, if defined. This value has
3404 precedence over the valu based on CONFIG_NET_RETRY_COUNT.
3405
Simon Glassbdded202020-06-02 19:26:49 -06003406 memmatches - Number of matches found by the last 'ms' command, in hex
3407
3408 memaddr - Address of the last match found by the 'ms' command, in hex,
3409 or 0 if none
3410
3411 mempos - Index position of the last match found by the 'ms' command,
3412 in units of the size (.b, .w, .l) of the search
3413
Simon Glass126f47c2020-09-05 14:50:48 -06003414 zbootbase - (x86 only) Base address of the bzImage 'setup' block
3415
3416 zbootaddr - (x86 only) Address of the loaded bzImage, typically
3417 BZIMAGE_LOAD_ADDR which is 0x100000
Simon Glassbdded202020-06-02 19:26:49 -06003418
Jason Hobbsdc0b7b02011-08-31 05:37:28 +00003419The following image location variables contain the location of images
3420used in booting. The "Image" column gives the role of the image and is
3421not an environment variable name. The other columns are environment
3422variable names. "File Name" gives the name of the file on a TFTP
3423server, "RAM Address" gives the location in RAM the image will be
3424loaded to, and "Flash Location" gives the image's address in NOR
3425flash or offset in NAND flash.
3426
3427*Note* - these variables don't have to be defined for all boards, some
Fabio Estevamaed9fed2015-04-25 18:53:10 -03003428boards currently use other variables for these purposes, and some
Jason Hobbsdc0b7b02011-08-31 05:37:28 +00003429boards use these variables for other purposes.
3430
Wolfgang Denkc0f40852011-10-26 10:21:21 +00003431Image File Name RAM Address Flash Location
3432----- --------- ----------- --------------
3433u-boot u-boot u-boot_addr_r u-boot_addr
3434Linux kernel bootfile kernel_addr_r kernel_addr
3435device tree blob fdtfile fdt_addr_r fdt_addr
3436ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr
Jason Hobbsdc0b7b02011-08-31 05:37:28 +00003437
wdenk2729af92004-05-03 20:45:30 +00003438The following environment variables may be used and automatically
3439updated by the network boot commands ("bootp" and "rarpboot"),
3440depending the information provided by your boot server:
wdenka3d991b2004-04-15 21:48:45 +00003441
wdenk2729af92004-05-03 20:45:30 +00003442 bootfile - see above
3443 dnsip - IP address of your Domain Name Server
3444 dnsip2 - IP address of your secondary Domain Name Server
3445 gatewayip - IP address of the Gateway (Router) to use
3446 hostname - Target hostname
3447 ipaddr - see above
3448 netmask - Subnet Mask
3449 rootpath - Pathname of the root filesystem on the NFS server
3450 serverip - see above
wdenka3d991b2004-04-15 21:48:45 +00003451
wdenka3d991b2004-04-15 21:48:45 +00003452
wdenk2729af92004-05-03 20:45:30 +00003453There are two special Environment Variables:
wdenkc6097192002-11-03 00:24:07 +00003454
wdenk2729af92004-05-03 20:45:30 +00003455 serial# - contains hardware identification information such
3456 as type string and/or serial number
3457 ethaddr - Ethernet address
wdenkc6097192002-11-03 00:24:07 +00003458
wdenk2729af92004-05-03 20:45:30 +00003459These variables can be set only once (usually during manufacturing of
3460the board). U-Boot refuses to delete or overwrite these variables
3461once they have been set once.
wdenkc6097192002-11-03 00:24:07 +00003462
3463
wdenk2729af92004-05-03 20:45:30 +00003464Further special Environment Variables:
wdenkc6097192002-11-03 00:24:07 +00003465
wdenk2729af92004-05-03 20:45:30 +00003466 ver - Contains the U-Boot version string as printed
3467 with the "version" command. This variable is
3468 readonly (see CONFIG_VERSION_VARIABLE).
wdenkc6097192002-11-03 00:24:07 +00003469
wdenkc6097192002-11-03 00:24:07 +00003470
wdenk2729af92004-05-03 20:45:30 +00003471Please note that changes to some configuration parameters may take
3472only effect after the next boot (yes, that's just like Windoze :-).
wdenkc6097192002-11-03 00:24:07 +00003473
stroesec1551ea2003-04-04 15:53:41 +00003474
Joe Hershberger170ab112012-12-11 22:16:24 -06003475Callback functions for environment variables:
3476---------------------------------------------
3477
3478For some environment variables, the behavior of u-boot needs to change
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08003479when their values are changed. This functionality allows functions to
Joe Hershberger170ab112012-12-11 22:16:24 -06003480be associated with arbitrary variables. On creation, overwrite, or
3481deletion, the callback will provide the opportunity for some side
3482effect to happen or for the change to be rejected.
3483
3484The callbacks are named and associated with a function using the
3485U_BOOT_ENV_CALLBACK macro in your board or driver code.
3486
3487These callbacks are associated with variables in one of two ways. The
3488static list can be added to by defining CONFIG_ENV_CALLBACK_LIST_STATIC
3489in the board configuration to a string that defines a list of
3490associations. The list must be in the following format:
3491
3492 entry = variable_name[:callback_name]
3493 list = entry[,list]
3494
3495If the callback name is not specified, then the callback is deleted.
3496Spaces are also allowed anywhere in the list.
3497
3498Callbacks can also be associated by defining the ".callbacks" variable
3499with the same list format above. Any association in ".callbacks" will
3500override any association in the static list. You can define
3501CONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08003502".callbacks" environment variable in the default or embedded environment.
Joe Hershberger170ab112012-12-11 22:16:24 -06003503
Joe Hershbergerbdf1fe42015-05-20 14:27:20 -05003504If CONFIG_REGEX is defined, the variable_name above is evaluated as a
3505regular expression. This allows multiple variables to be connected to
3506the same callback without explicitly listing them all out.
3507
Heinrich Schuchardt1b040472018-07-29 11:08:14 +02003508The signature of the callback functions is:
3509
3510 int callback(const char *name, const char *value, enum env_op op, int flags)
3511
3512* name - changed environment variable
3513* value - new value of the environment variable
3514* op - operation (create, overwrite, or delete)
3515* flags - attributes of the environment variable change, see flags H_* in
3516 include/search.h
3517
3518The return value is 0 if the variable change is accepted and 1 otherwise.
Joe Hershberger170ab112012-12-11 22:16:24 -06003519
wdenk2729af92004-05-03 20:45:30 +00003520Command Line Parsing:
3521=====================
stroesec1551ea2003-04-04 15:53:41 +00003522
wdenk2729af92004-05-03 20:45:30 +00003523There are two different command line parsers available with U-Boot:
3524the old "simple" one, and the much more powerful "hush" shell:
stroesec1551ea2003-04-04 15:53:41 +00003525
wdenk2729af92004-05-03 20:45:30 +00003526Old, simple command line parser:
3527--------------------------------
wdenkc6097192002-11-03 00:24:07 +00003528
wdenk2729af92004-05-03 20:45:30 +00003529- supports environment variables (through setenv / saveenv commands)
3530- several commands on one line, separated by ';'
Wolfgang Denkfe126d82005-11-20 21:40:11 +01003531- variable substitution using "... ${name} ..." syntax
wdenk2729af92004-05-03 20:45:30 +00003532- special characters ('$', ';') can be escaped by prefixing with '\',
3533 for example:
Wolfgang Denkfe126d82005-11-20 21:40:11 +01003534 setenv bootcmd bootm \${address}
wdenk2729af92004-05-03 20:45:30 +00003535- You can also escape text by enclosing in single apostrophes, for example:
3536 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
wdenkc6097192002-11-03 00:24:07 +00003537
wdenk2729af92004-05-03 20:45:30 +00003538Hush shell:
3539-----------
wdenkf07771c2003-05-28 08:06:31 +00003540
wdenk2729af92004-05-03 20:45:30 +00003541- similar to Bourne shell, with control structures like
3542 if...then...else...fi, for...do...done; while...do...done,
3543 until...do...done, ...
3544- supports environment ("global") variables (through setenv / saveenv
3545 commands) and local shell variables (through standard shell syntax
3546 "name=value"); only environment variables can be used with "run"
3547 command
wdenkf07771c2003-05-28 08:06:31 +00003548
wdenk2729af92004-05-03 20:45:30 +00003549General rules:
3550--------------
wdenkf07771c2003-05-28 08:06:31 +00003551
wdenk2729af92004-05-03 20:45:30 +00003552(1) If a command line (or an environment variable executed by a "run"
3553 command) contains several commands separated by semicolon, and
3554 one of these commands fails, then the remaining commands will be
3555 executed anyway.
wdenkf07771c2003-05-28 08:06:31 +00003556
wdenk2729af92004-05-03 20:45:30 +00003557(2) If you execute several variables with one call to run (i. e.
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02003558 calling run with a list of variables as arguments), any failing
wdenk2729af92004-05-03 20:45:30 +00003559 command will cause "run" to terminate, i. e. the remaining
3560 variables are not executed.
wdenkf07771c2003-05-28 08:06:31 +00003561
wdenk2729af92004-05-03 20:45:30 +00003562Note for Redundant Ethernet Interfaces:
3563=======================================
wdenkf07771c2003-05-28 08:06:31 +00003564
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02003565Some boards come with redundant Ethernet interfaces; U-Boot supports
wdenk2729af92004-05-03 20:45:30 +00003566such configurations and is capable of automatic selection of a
3567"working" interface when needed. MAC assignment works as follows:
wdenkf07771c2003-05-28 08:06:31 +00003568
wdenk2729af92004-05-03 20:45:30 +00003569Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
3570MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
3571"eth1addr" (=>eth1), "eth2addr", ...
wdenkf07771c2003-05-28 08:06:31 +00003572
wdenk2729af92004-05-03 20:45:30 +00003573If the network interface stores some valid MAC address (for instance
3574in SROM), this is used as default address if there is NO correspon-
3575ding setting in the environment; if the corresponding environment
3576variable is set, this overrides the settings in the card; that means:
wdenkf07771c2003-05-28 08:06:31 +00003577
wdenk2729af92004-05-03 20:45:30 +00003578o If the SROM has a valid MAC address, and there is no address in the
3579 environment, the SROM's address is used.
wdenkc6097192002-11-03 00:24:07 +00003580
wdenk2729af92004-05-03 20:45:30 +00003581o If there is no valid address in the SROM, and a definition in the
3582 environment exists, then the value from the environment variable is
3583 used.
wdenkc6097192002-11-03 00:24:07 +00003584
wdenk2729af92004-05-03 20:45:30 +00003585o If both the SROM and the environment contain a MAC address, and
3586 both addresses are the same, this MAC address is used.
wdenkc6097192002-11-03 00:24:07 +00003587
wdenk2729af92004-05-03 20:45:30 +00003588o If both the SROM and the environment contain a MAC address, and the
3589 addresses differ, the value from the environment is used and a
3590 warning is printed.
wdenkc6097192002-11-03 00:24:07 +00003591
wdenk2729af92004-05-03 20:45:30 +00003592o If neither SROM nor the environment contain a MAC address, an error
Joe Hershbergerbef10142015-05-04 14:55:13 -05003593 is raised. If CONFIG_NET_RANDOM_ETHADDR is defined, then in this case
3594 a random, locally-assigned MAC is used.
wdenkc6097192002-11-03 00:24:07 +00003595
Ben Warrenecee9322010-04-26 11:11:46 -07003596If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses
Wolfgang Denkc0f40852011-10-26 10:21:21 +00003597will be programmed into hardware as part of the initialization process. This
Ben Warrenecee9322010-04-26 11:11:46 -07003598may be skipped by setting the appropriate 'ethmacskip' environment variable.
3599The naming convention is as follows:
3600"ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc.
wdenkc6097192002-11-03 00:24:07 +00003601
wdenk2729af92004-05-03 20:45:30 +00003602Image Formats:
3603==============
wdenkc6097192002-11-03 00:24:07 +00003604
Marian Balakowicz3310c542008-03-12 12:13:13 +01003605U-Boot is capable of booting (and performing other auxiliary operations on)
3606images in two formats:
3607
3608New uImage format (FIT)
3609-----------------------
3610
3611Flexible and powerful format based on Flattened Image Tree -- FIT (similar
3612to Flattened Device Tree). It allows the use of images with multiple
3613components (several kernels, ramdisks, etc.), with contents protected by
3614SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
3615
3616
3617Old uImage format
3618-----------------
3619
3620Old image format is based on binary files which can be basically anything,
3621preceded by a special header; see the definitions in include/image.h for
3622details; basically, the header defines the following image properties:
wdenkc6097192002-11-03 00:24:07 +00003623
wdenk2729af92004-05-03 20:45:30 +00003624* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
3625 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
Peter Tyserf5ed9e32008-09-08 14:56:49 -05003626 LynxOS, pSOS, QNX, RTEMS, INTEGRITY;
3627 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS,
3628 INTEGRITY).
Andy Shevchenkodaab59a2017-07-05 16:25:22 +03003629* Target CPU Architecture (Provisions for Alpha, ARM, Intel x86,
Macpaul Linafc1ce82011-10-19 20:41:11 +00003630 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
Andy Shevchenkodaab59a2017-07-05 16:25:22 +03003631 Currently supported: ARM, Intel x86, MIPS, NDS32, Nios II, PowerPC).
wdenk2729af92004-05-03 20:45:30 +00003632* Compression Type (uncompressed, gzip, bzip2)
3633* Load Address
3634* Entry Point
3635* Image Name
3636* Image Timestamp
wdenkc6097192002-11-03 00:24:07 +00003637
wdenk2729af92004-05-03 20:45:30 +00003638The header is marked by a special Magic Number, and both the header
3639and the data portions of the image are secured against corruption by
3640CRC32 checksums.
wdenkc6097192002-11-03 00:24:07 +00003641
wdenkc6097192002-11-03 00:24:07 +00003642
wdenk2729af92004-05-03 20:45:30 +00003643Linux Support:
3644==============
wdenkc6097192002-11-03 00:24:07 +00003645
wdenk2729af92004-05-03 20:45:30 +00003646Although U-Boot should support any OS or standalone application
3647easily, the main focus has always been on Linux during the design of
3648U-Boot.
wdenkc6097192002-11-03 00:24:07 +00003649
wdenk2729af92004-05-03 20:45:30 +00003650U-Boot includes many features that so far have been part of some
3651special "boot loader" code within the Linux kernel. Also, any
3652"initrd" images to be used are no longer part of one big Linux image;
3653instead, kernel and "initrd" are separate images. This implementation
3654serves several purposes:
wdenkc6097192002-11-03 00:24:07 +00003655
wdenk2729af92004-05-03 20:45:30 +00003656- the same features can be used for other OS or standalone
3657 applications (for instance: using compressed images to reduce the
3658 Flash memory footprint)
wdenkc6097192002-11-03 00:24:07 +00003659
wdenk2729af92004-05-03 20:45:30 +00003660- it becomes much easier to port new Linux kernel versions because
3661 lots of low-level, hardware dependent stuff are done by U-Boot
wdenkc6097192002-11-03 00:24:07 +00003662
wdenk2729af92004-05-03 20:45:30 +00003663- the same Linux kernel image can now be used with different "initrd"
3664 images; of course this also means that different kernel images can
3665 be run with the same "initrd". This makes testing easier (you don't
3666 have to build a new "zImage.initrd" Linux image when you just
3667 change a file in your "initrd"). Also, a field-upgrade of the
3668 software is easier now.
wdenkc6097192002-11-03 00:24:07 +00003669
wdenkc6097192002-11-03 00:24:07 +00003670
wdenk2729af92004-05-03 20:45:30 +00003671Linux HOWTO:
3672============
wdenkc6097192002-11-03 00:24:07 +00003673
wdenk2729af92004-05-03 20:45:30 +00003674Porting Linux to U-Boot based systems:
3675---------------------------------------
wdenkc6097192002-11-03 00:24:07 +00003676
wdenk2729af92004-05-03 20:45:30 +00003677U-Boot cannot save you from doing all the necessary modifications to
3678configure the Linux device drivers for use with your target hardware
3679(no, we don't intend to provide a full virtual machine interface to
3680Linux :-).
wdenkc6097192002-11-03 00:24:07 +00003681
Stefan Roesea47a12b2010-04-15 16:07:28 +02003682But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot).
wdenkc6097192002-11-03 00:24:07 +00003683
wdenk2729af92004-05-03 20:45:30 +00003684Just make sure your machine specific header file (for instance
3685include/asm-ppc/tqm8xx.h) includes the same definition of the Board
Markus Heidelberg1dc30692008-09-07 20:18:27 +02003686Information structure as we define in include/asm-<arch>/u-boot.h,
3687and make sure that your definition of IMAP_ADDR uses the same value
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003688as your U-Boot configuration in CONFIG_SYS_IMMR.
wdenkc6097192002-11-03 00:24:07 +00003689
Simon Glass2eb31b12014-06-11 23:29:46 -06003690Note that U-Boot now has a driver model, a unified model for drivers.
3691If you are adding a new driver, plumb it into driver model. If there
3692is no uclass available, you are encouraged to create one. See
3693doc/driver-model.
3694
wdenkc6097192002-11-03 00:24:07 +00003695
wdenk2729af92004-05-03 20:45:30 +00003696Configuring the Linux kernel:
3697-----------------------------
wdenkc6097192002-11-03 00:24:07 +00003698
wdenk2729af92004-05-03 20:45:30 +00003699No specific requirements for U-Boot. Make sure you have some root
3700device (initial ramdisk, NFS) for your target system.
wdenkc6097192002-11-03 00:24:07 +00003701
wdenkc6097192002-11-03 00:24:07 +00003702
wdenk2729af92004-05-03 20:45:30 +00003703Building a Linux Image:
3704-----------------------
wdenkc6097192002-11-03 00:24:07 +00003705
wdenk2729af92004-05-03 20:45:30 +00003706With U-Boot, "normal" build targets like "zImage" or "bzImage" are
3707not used. If you use recent kernel source, a new build target
3708"uImage" will exist which automatically builds an image usable by
3709U-Boot. Most older kernels also have support for a "pImage" target,
3710which was introduced for our predecessor project PPCBoot and uses a
3711100% compatible format.
wdenkc6097192002-11-03 00:24:07 +00003712
wdenk2729af92004-05-03 20:45:30 +00003713Example:
wdenkc6097192002-11-03 00:24:07 +00003714
Holger Freytherab584d62014-08-04 09:26:05 +02003715 make TQM850L_defconfig
wdenk2729af92004-05-03 20:45:30 +00003716 make oldconfig
3717 make dep
3718 make uImage
wdenkc6097192002-11-03 00:24:07 +00003719
wdenk2729af92004-05-03 20:45:30 +00003720The "uImage" build target uses a special tool (in 'tools/mkimage') to
3721encapsulate a compressed Linux kernel image with header information,
3722CRC32 checksum etc. for use with U-Boot. This is what we are doing:
wdenkc6097192002-11-03 00:24:07 +00003723
wdenk2729af92004-05-03 20:45:30 +00003724* build a standard "vmlinux" kernel image (in ELF binary format):
wdenkc6097192002-11-03 00:24:07 +00003725
wdenk2729af92004-05-03 20:45:30 +00003726* convert the kernel into a raw binary image:
wdenkc6097192002-11-03 00:24:07 +00003727
wdenk2729af92004-05-03 20:45:30 +00003728 ${CROSS_COMPILE}-objcopy -O binary \
3729 -R .note -R .comment \
3730 -S vmlinux linux.bin
wdenkc6097192002-11-03 00:24:07 +00003731
wdenk2729af92004-05-03 20:45:30 +00003732* compress the binary image:
wdenkc6097192002-11-03 00:24:07 +00003733
wdenk2729af92004-05-03 20:45:30 +00003734 gzip -9 linux.bin
wdenkc6097192002-11-03 00:24:07 +00003735
wdenk2729af92004-05-03 20:45:30 +00003736* package compressed binary image for U-Boot:
wdenk24ee89b2002-11-03 17:56:27 +00003737
wdenk2729af92004-05-03 20:45:30 +00003738 mkimage -A ppc -O linux -T kernel -C gzip \
3739 -a 0 -e 0 -n "Linux Kernel Image" \
3740 -d linux.bin.gz uImage
wdenk24ee89b2002-11-03 17:56:27 +00003741
wdenk24ee89b2002-11-03 17:56:27 +00003742
wdenk2729af92004-05-03 20:45:30 +00003743The "mkimage" tool can also be used to create ramdisk images for use
3744with U-Boot, either separated from the Linux kernel image, or
3745combined into one file. "mkimage" encapsulates the images with a 64
3746byte header containing information about target architecture,
3747operating system, image type, compression method, entry points, time
3748stamp, CRC32 checksums, etc.
wdenk24ee89b2002-11-03 17:56:27 +00003749
wdenk2729af92004-05-03 20:45:30 +00003750"mkimage" can be called in two ways: to verify existing images and
3751print the header information, or to build new images.
wdenk24ee89b2002-11-03 17:56:27 +00003752
wdenk2729af92004-05-03 20:45:30 +00003753In the first form (with "-l" option) mkimage lists the information
3754contained in the header of an existing U-Boot image; this includes
3755checksum verification:
wdenk24ee89b2002-11-03 17:56:27 +00003756
wdenk2729af92004-05-03 20:45:30 +00003757 tools/mkimage -l image
3758 -l ==> list image header information
wdenk24ee89b2002-11-03 17:56:27 +00003759
wdenk2729af92004-05-03 20:45:30 +00003760The second form (with "-d" option) is used to build a U-Boot image
3761from a "data file" which is used as image payload:
wdenk24ee89b2002-11-03 17:56:27 +00003762
wdenk2729af92004-05-03 20:45:30 +00003763 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
3764 -n name -d data_file image
3765 -A ==> set architecture to 'arch'
3766 -O ==> set operating system to 'os'
3767 -T ==> set image type to 'type'
3768 -C ==> set compression type 'comp'
3769 -a ==> set load address to 'addr' (hex)
3770 -e ==> set entry point to 'ep' (hex)
3771 -n ==> set image name to 'name'
3772 -d ==> use image data from 'datafile'
wdenk24ee89b2002-11-03 17:56:27 +00003773
wdenk69459792004-05-29 16:53:29 +00003774Right now, all Linux kernels for PowerPC systems use the same load
3775address (0x00000000), but the entry point address depends on the
3776kernel version:
wdenkc6097192002-11-03 00:24:07 +00003777
wdenk2729af92004-05-03 20:45:30 +00003778- 2.2.x kernels have the entry point at 0x0000000C,
3779- 2.3.x and later kernels have the entry point at 0x00000000.
wdenkc6097192002-11-03 00:24:07 +00003780
wdenk2729af92004-05-03 20:45:30 +00003781So a typical call to build a U-Boot image would read:
wdenkc6097192002-11-03 00:24:07 +00003782
wdenk2729af92004-05-03 20:45:30 +00003783 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
3784 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
Stefan Roesea47a12b2010-04-15 16:07:28 +02003785 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \
wdenk2729af92004-05-03 20:45:30 +00003786 > examples/uImage.TQM850L
3787 Image Name: 2.4.4 kernel for TQM850L
3788 Created: Wed Jul 19 02:34:59 2000
3789 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3790 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
3791 Load Address: 0x00000000
3792 Entry Point: 0x00000000
wdenkc6097192002-11-03 00:24:07 +00003793
wdenk2729af92004-05-03 20:45:30 +00003794To verify the contents of the image (or check for corruption):
wdenkc6097192002-11-03 00:24:07 +00003795
wdenk2729af92004-05-03 20:45:30 +00003796 -> tools/mkimage -l examples/uImage.TQM850L
3797 Image Name: 2.4.4 kernel for TQM850L
3798 Created: Wed Jul 19 02:34:59 2000
3799 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3800 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
3801 Load Address: 0x00000000
3802 Entry Point: 0x00000000
wdenkc6097192002-11-03 00:24:07 +00003803
wdenk2729af92004-05-03 20:45:30 +00003804NOTE: for embedded systems where boot time is critical you can trade
3805speed for memory and install an UNCOMPRESSED image instead: this
3806needs more space in Flash, but boots much faster since it does not
3807need to be uncompressed:
wdenkc6097192002-11-03 00:24:07 +00003808
Stefan Roesea47a12b2010-04-15 16:07:28 +02003809 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz
wdenk2729af92004-05-03 20:45:30 +00003810 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
3811 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
Stefan Roesea47a12b2010-04-15 16:07:28 +02003812 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \
wdenk2729af92004-05-03 20:45:30 +00003813 > examples/uImage.TQM850L-uncompressed
3814 Image Name: 2.4.4 kernel for TQM850L
3815 Created: Wed Jul 19 02:34:59 2000
3816 Image Type: PowerPC Linux Kernel Image (uncompressed)
3817 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
3818 Load Address: 0x00000000
3819 Entry Point: 0x00000000
wdenkc6097192002-11-03 00:24:07 +00003820
wdenkc6097192002-11-03 00:24:07 +00003821
wdenk2729af92004-05-03 20:45:30 +00003822Similar you can build U-Boot images from a 'ramdisk.image.gz' file
3823when your kernel is intended to use an initial ramdisk:
wdenkdb01a2e2004-04-15 23:14:49 +00003824
wdenk2729af92004-05-03 20:45:30 +00003825 -> tools/mkimage -n 'Simple Ramdisk Image' \
3826 > -A ppc -O linux -T ramdisk -C gzip \
3827 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
3828 Image Name: Simple Ramdisk Image
3829 Created: Wed Jan 12 14:01:50 2000
3830 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
3831 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
3832 Load Address: 0x00000000
3833 Entry Point: 0x00000000
wdenkdb01a2e2004-04-15 23:14:49 +00003834
Tyler Hickse157a112020-10-26 10:40:24 -05003835The "dumpimage" tool can be used to disassemble or list the contents of images
3836built by mkimage. See dumpimage's help output (-h) for details.
wdenkdb01a2e2004-04-15 23:14:49 +00003837
wdenk2729af92004-05-03 20:45:30 +00003838Installing a Linux Image:
3839-------------------------
wdenkdb01a2e2004-04-15 23:14:49 +00003840
wdenk2729af92004-05-03 20:45:30 +00003841To downloading a U-Boot image over the serial (console) interface,
3842you must convert the image to S-Record format:
wdenkdb01a2e2004-04-15 23:14:49 +00003843
wdenk2729af92004-05-03 20:45:30 +00003844 objcopy -I binary -O srec examples/image examples/image.srec
wdenkdb01a2e2004-04-15 23:14:49 +00003845
wdenk2729af92004-05-03 20:45:30 +00003846The 'objcopy' does not understand the information in the U-Boot
3847image header, so the resulting S-Record file will be relative to
3848address 0x00000000. To load it to a given address, you need to
3849specify the target address as 'offset' parameter with the 'loads'
3850command.
wdenkc6097192002-11-03 00:24:07 +00003851
wdenk2729af92004-05-03 20:45:30 +00003852Example: install the image to address 0x40100000 (which on the
3853TQM8xxL is in the first Flash bank):
wdenkc6097192002-11-03 00:24:07 +00003854
wdenk2729af92004-05-03 20:45:30 +00003855 => erase 40100000 401FFFFF
wdenkc6097192002-11-03 00:24:07 +00003856
wdenk2729af92004-05-03 20:45:30 +00003857 .......... done
3858 Erased 8 sectors
wdenkc6097192002-11-03 00:24:07 +00003859
wdenk2729af92004-05-03 20:45:30 +00003860 => loads 40100000
3861 ## Ready for S-Record download ...
3862 ~>examples/image.srec
3863 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
3864 ...
3865 15989 15990 15991 15992
3866 [file transfer complete]
3867 [connected]
3868 ## Start Addr = 0x00000000
wdenkc6097192002-11-03 00:24:07 +00003869
3870
wdenk2729af92004-05-03 20:45:30 +00003871You can check the success of the download using the 'iminfo' command;
Wolfgang Denk218ca722008-03-26 10:40:12 +01003872this includes a checksum verification so you can be sure no data
wdenk2729af92004-05-03 20:45:30 +00003873corruption happened:
wdenkc6097192002-11-03 00:24:07 +00003874
wdenk2729af92004-05-03 20:45:30 +00003875 => imi 40100000
wdenkc6097192002-11-03 00:24:07 +00003876
wdenk2729af92004-05-03 20:45:30 +00003877 ## Checking Image at 40100000 ...
3878 Image Name: 2.2.13 for initrd on TQM850L
3879 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3880 Data Size: 335725 Bytes = 327 kB = 0 MB
3881 Load Address: 00000000
3882 Entry Point: 0000000c
3883 Verifying Checksum ... OK
wdenkc6097192002-11-03 00:24:07 +00003884
3885
wdenk2729af92004-05-03 20:45:30 +00003886Boot Linux:
3887-----------
wdenkc6097192002-11-03 00:24:07 +00003888
wdenk2729af92004-05-03 20:45:30 +00003889The "bootm" command is used to boot an application that is stored in
3890memory (RAM or Flash). In case of a Linux kernel image, the contents
3891of the "bootargs" environment variable is passed to the kernel as
3892parameters. You can check and modify this variable using the
3893"printenv" and "setenv" commands:
wdenkc6097192002-11-03 00:24:07 +00003894
3895
wdenk2729af92004-05-03 20:45:30 +00003896 => printenv bootargs
3897 bootargs=root=/dev/ram
wdenkc6097192002-11-03 00:24:07 +00003898
wdenk2729af92004-05-03 20:45:30 +00003899 => 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 +00003900
wdenk2729af92004-05-03 20:45:30 +00003901 => printenv bootargs
3902 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 +00003903
wdenk2729af92004-05-03 20:45:30 +00003904 => bootm 40020000
3905 ## Booting Linux kernel at 40020000 ...
3906 Image Name: 2.2.13 for NFS on TQM850L
3907 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3908 Data Size: 381681 Bytes = 372 kB = 0 MB
3909 Load Address: 00000000
3910 Entry Point: 0000000c
3911 Verifying Checksum ... OK
3912 Uncompressing Kernel Image ... OK
3913 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
3914 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
3915 time_init: decrementer frequency = 187500000/60
3916 Calibrating delay loop... 49.77 BogoMIPS
3917 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
3918 ...
wdenkc6097192002-11-03 00:24:07 +00003919
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02003920If you want to boot a Linux kernel with initial RAM disk, you pass
wdenk2729af92004-05-03 20:45:30 +00003921the memory addresses of both the kernel and the initrd image (PPBCOOT
3922format!) to the "bootm" command:
wdenkc6097192002-11-03 00:24:07 +00003923
wdenk2729af92004-05-03 20:45:30 +00003924 => imi 40100000 40200000
wdenkc6097192002-11-03 00:24:07 +00003925
wdenk2729af92004-05-03 20:45:30 +00003926 ## Checking Image at 40100000 ...
3927 Image Name: 2.2.13 for initrd on TQM850L
3928 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3929 Data Size: 335725 Bytes = 327 kB = 0 MB
3930 Load Address: 00000000
3931 Entry Point: 0000000c
3932 Verifying Checksum ... OK
wdenkc6097192002-11-03 00:24:07 +00003933
wdenk2729af92004-05-03 20:45:30 +00003934 ## Checking Image at 40200000 ...
3935 Image Name: Simple Ramdisk Image
3936 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
3937 Data Size: 566530 Bytes = 553 kB = 0 MB
3938 Load Address: 00000000
3939 Entry Point: 00000000
3940 Verifying Checksum ... OK
wdenkc6097192002-11-03 00:24:07 +00003941
wdenk2729af92004-05-03 20:45:30 +00003942 => bootm 40100000 40200000
3943 ## Booting Linux kernel at 40100000 ...
3944 Image Name: 2.2.13 for initrd on TQM850L
3945 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3946 Data Size: 335725 Bytes = 327 kB = 0 MB
3947 Load Address: 00000000
3948 Entry Point: 0000000c
3949 Verifying Checksum ... OK
3950 Uncompressing Kernel Image ... OK
3951 ## Loading RAMDisk Image at 40200000 ...
3952 Image Name: Simple Ramdisk Image
3953 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
3954 Data Size: 566530 Bytes = 553 kB = 0 MB
3955 Load Address: 00000000
3956 Entry Point: 00000000
3957 Verifying Checksum ... OK
3958 Loading Ramdisk ... OK
3959 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
3960 Boot arguments: root=/dev/ram
3961 time_init: decrementer frequency = 187500000/60
3962 Calibrating delay loop... 49.77 BogoMIPS
3963 ...
3964 RAMDISK: Compressed image found at block 0
3965 VFS: Mounted root (ext2 filesystem).
wdenkc6097192002-11-03 00:24:07 +00003966
wdenk2729af92004-05-03 20:45:30 +00003967 bash#
wdenkc6097192002-11-03 00:24:07 +00003968
Matthew McClintock02677682006-06-28 10:41:37 -05003969Boot Linux and pass a flat device tree:
3970-----------
3971
3972First, U-Boot must be compiled with the appropriate defines. See the section
3973titled "Linux Kernel Interface" above for a more in depth explanation. The
3974following is an example of how to start a kernel and pass an updated
3975flat device tree:
3976
3977=> print oftaddr
3978oftaddr=0x300000
3979=> print oft
3980oft=oftrees/mpc8540ads.dtb
3981=> tftp $oftaddr $oft
3982Speed: 1000, full duplex
3983Using TSEC0 device
3984TFTP from server 192.168.1.1; our IP address is 192.168.1.101
3985Filename 'oftrees/mpc8540ads.dtb'.
3986Load address: 0x300000
3987Loading: #
3988done
3989Bytes transferred = 4106 (100a hex)
3990=> tftp $loadaddr $bootfile
3991Speed: 1000, full duplex
3992Using TSEC0 device
3993TFTP from server 192.168.1.1; our IP address is 192.168.1.2
3994Filename 'uImage'.
3995Load address: 0x200000
3996Loading:############
3997done
3998Bytes transferred = 1029407 (fb51f hex)
3999=> print loadaddr
4000loadaddr=200000
4001=> print oftaddr
4002oftaddr=0x300000
4003=> bootm $loadaddr - $oftaddr
4004## Booting image at 00200000 ...
Wolfgang Denka9398e02006-11-27 15:32:42 +01004005 Image Name: Linux-2.6.17-dirty
4006 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4007 Data Size: 1029343 Bytes = 1005.2 kB
Matthew McClintock02677682006-06-28 10:41:37 -05004008 Load Address: 00000000
Wolfgang Denka9398e02006-11-27 15:32:42 +01004009 Entry Point: 00000000
Matthew McClintock02677682006-06-28 10:41:37 -05004010 Verifying Checksum ... OK
4011 Uncompressing Kernel Image ... OK
4012Booting using flat device tree at 0x300000
4013Using MPC85xx ADS machine description
4014Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb
4015[snip]
4016
4017
wdenk2729af92004-05-03 20:45:30 +00004018More About U-Boot Image Types:
4019------------------------------
wdenk6069ff22003-02-28 00:49:47 +00004020
wdenk2729af92004-05-03 20:45:30 +00004021U-Boot supports the following image types:
wdenk6069ff22003-02-28 00:49:47 +00004022
wdenk2729af92004-05-03 20:45:30 +00004023 "Standalone Programs" are directly runnable in the environment
4024 provided by U-Boot; it is expected that (if they behave
4025 well) you can continue to work in U-Boot after return from
4026 the Standalone Program.
4027 "OS Kernel Images" are usually images of some Embedded OS which
4028 will take over control completely. Usually these programs
4029 will install their own set of exception handlers, device
4030 drivers, set up the MMU, etc. - this means, that you cannot
4031 expect to re-enter U-Boot except by resetting the CPU.
4032 "RAMDisk Images" are more or less just data blocks, and their
4033 parameters (address, size) are passed to an OS kernel that is
4034 being started.
4035 "Multi-File Images" contain several images, typically an OS
4036 (Linux) kernel image and one or more data images like
4037 RAMDisks. This construct is useful for instance when you want
4038 to boot over the network using BOOTP etc., where the boot
4039 server provides just a single image file, but you want to get
4040 for instance an OS kernel and a RAMDisk image.
stroesec1551ea2003-04-04 15:53:41 +00004041
wdenk2729af92004-05-03 20:45:30 +00004042 "Multi-File Images" start with a list of image sizes, each
4043 image size (in bytes) specified by an "uint32_t" in network
4044 byte order. This list is terminated by an "(uint32_t)0".
4045 Immediately after the terminating 0 follow the images, one by
4046 one, all aligned on "uint32_t" boundaries (size rounded up to
4047 a multiple of 4 bytes).
stroesec1551ea2003-04-04 15:53:41 +00004048
wdenk2729af92004-05-03 20:45:30 +00004049 "Firmware Images" are binary images containing firmware (like
4050 U-Boot or FPGA images) which usually will be programmed to
4051 flash memory.
stroesec1551ea2003-04-04 15:53:41 +00004052
wdenk2729af92004-05-03 20:45:30 +00004053 "Script files" are command sequences that will be executed by
4054 U-Boot's command interpreter; this feature is especially
4055 useful when you configure U-Boot to use a real shell (hush)
4056 as command interpreter.
wdenk6069ff22003-02-28 00:49:47 +00004057
Marek Vasut44f074c2012-03-14 21:52:45 +00004058Booting the Linux zImage:
4059-------------------------
4060
4061On some platforms, it's possible to boot Linux zImage. This is done
4062using the "bootz" command. The syntax of "bootz" command is the same
4063as the syntax of "bootm" command.
4064
Tom Rini8ac28562013-05-16 11:40:11 -04004065Note, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply
Marek Vasut017e1f32012-03-18 11:47:58 +00004066kernel with raw initrd images. The syntax is slightly different, the
4067address of the initrd must be augmented by it's size, in the following
4068format: "<initrd addres>:<initrd size>".
4069
wdenkc6097192002-11-03 00:24:07 +00004070
wdenk2729af92004-05-03 20:45:30 +00004071Standalone HOWTO:
4072=================
wdenkc6097192002-11-03 00:24:07 +00004073
wdenk2729af92004-05-03 20:45:30 +00004074One of the features of U-Boot is that you can dynamically load and
4075run "standalone" applications, which can use some resources of
4076U-Boot like console I/O functions or interrupt services.
wdenkc6097192002-11-03 00:24:07 +00004077
wdenk2729af92004-05-03 20:45:30 +00004078Two simple examples are included with the sources:
wdenkc6097192002-11-03 00:24:07 +00004079
wdenk2729af92004-05-03 20:45:30 +00004080"Hello World" Demo:
4081-------------------
wdenkc6097192002-11-03 00:24:07 +00004082
wdenk2729af92004-05-03 20:45:30 +00004083'examples/hello_world.c' contains a small "Hello World" Demo
4084application; it is automatically compiled when you build U-Boot.
4085It's configured to run at address 0x00040004, so you can play with it
4086like that:
wdenkc6097192002-11-03 00:24:07 +00004087
wdenk2729af92004-05-03 20:45:30 +00004088 => loads
4089 ## Ready for S-Record download ...
4090 ~>examples/hello_world.srec
4091 1 2 3 4 5 6 7 8 9 10 11 ...
4092 [file transfer complete]
4093 [connected]
4094 ## Start Addr = 0x00040004
wdenkc6097192002-11-03 00:24:07 +00004095
wdenk2729af92004-05-03 20:45:30 +00004096 => go 40004 Hello World! This is a test.
4097 ## Starting application at 0x00040004 ...
4098 Hello World
4099 argc = 7
4100 argv[0] = "40004"
4101 argv[1] = "Hello"
4102 argv[2] = "World!"
4103 argv[3] = "This"
4104 argv[4] = "is"
4105 argv[5] = "a"
4106 argv[6] = "test."
4107 argv[7] = "<NULL>"
4108 Hit any key to exit ...
wdenkc6097192002-11-03 00:24:07 +00004109
wdenk2729af92004-05-03 20:45:30 +00004110 ## Application terminated, rc = 0x0
wdenkc6097192002-11-03 00:24:07 +00004111
wdenk2729af92004-05-03 20:45:30 +00004112Another example, which demonstrates how to register a CPM interrupt
4113handler with the U-Boot code, can be found in 'examples/timer.c'.
4114Here, a CPM timer is set up to generate an interrupt every second.
4115The interrupt service routine is trivial, just printing a '.'
4116character, but this is just a demo program. The application can be
4117controlled by the following keys:
wdenkc6097192002-11-03 00:24:07 +00004118
wdenk2729af92004-05-03 20:45:30 +00004119 ? - print current values og the CPM Timer registers
4120 b - enable interrupts and start timer
4121 e - stop timer and disable interrupts
4122 q - quit application
wdenkc6097192002-11-03 00:24:07 +00004123
wdenk2729af92004-05-03 20:45:30 +00004124 => loads
4125 ## Ready for S-Record download ...
4126 ~>examples/timer.srec
4127 1 2 3 4 5 6 7 8 9 10 11 ...
4128 [file transfer complete]
4129 [connected]
4130 ## Start Addr = 0x00040004
wdenkc6097192002-11-03 00:24:07 +00004131
wdenk2729af92004-05-03 20:45:30 +00004132 => go 40004
4133 ## Starting application at 0x00040004 ...
4134 TIMERS=0xfff00980
4135 Using timer 1
4136 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
wdenkc6097192002-11-03 00:24:07 +00004137
wdenk2729af92004-05-03 20:45:30 +00004138Hit 'b':
4139 [q, b, e, ?] Set interval 1000000 us
4140 Enabling timer
4141Hit '?':
4142 [q, b, e, ?] ........
4143 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
4144Hit '?':
4145 [q, b, e, ?] .
4146 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
4147Hit '?':
4148 [q, b, e, ?] .
4149 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
4150Hit '?':
4151 [q, b, e, ?] .
4152 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
4153Hit 'e':
4154 [q, b, e, ?] ...Stopping timer
4155Hit 'q':
4156 [q, b, e, ?] ## Application terminated, rc = 0x0
wdenkc6097192002-11-03 00:24:07 +00004157
4158
wdenk2729af92004-05-03 20:45:30 +00004159Minicom warning:
4160================
wdenk85ec0bc2003-03-31 16:34:49 +00004161
wdenk2729af92004-05-03 20:45:30 +00004162Over time, many people have reported problems when trying to use the
4163"minicom" terminal emulation program for serial download. I (wd)
4164consider minicom to be broken, and recommend not to use it. Under
4165Unix, I recommend to use C-Kermit for general purpose use (and
4166especially for kermit binary protocol download ("loadb" command), and
Karl O. Pince53515a2012-10-01 05:11:56 +00004167use "cu" for S-Record download ("loads" command). See
Naoki Hayama047f6ec2020-10-08 13:17:16 +09004168https://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3.
Karl O. Pince53515a2012-10-01 05:11:56 +00004169for help with kermit.
4170
wdenk85ec0bc2003-03-31 16:34:49 +00004171
wdenk2729af92004-05-03 20:45:30 +00004172Nevertheless, if you absolutely want to use it try adding this
4173configuration to your "File transfer protocols" section:
wdenk52f52c12003-06-19 23:04:19 +00004174
wdenk2729af92004-05-03 20:45:30 +00004175 Name Program Name U/D FullScr IO-Red. Multi
4176 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
4177 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
wdenk52f52c12003-06-19 23:04:19 +00004178
4179
wdenk2729af92004-05-03 20:45:30 +00004180NetBSD Notes:
4181=============
wdenkc6097192002-11-03 00:24:07 +00004182
wdenk2729af92004-05-03 20:45:30 +00004183Starting at version 0.9.2, U-Boot supports NetBSD both as host
4184(build U-Boot) and target system (boots NetBSD/mpc8xx).
wdenkc6097192002-11-03 00:24:07 +00004185
wdenk2729af92004-05-03 20:45:30 +00004186Building requires a cross environment; it is known to work on
4187NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
4188need gmake since the Makefiles are not compatible with BSD make).
4189Note that the cross-powerpc package does not install include files;
4190attempting to build U-Boot will fail because <machine/ansi.h> is
4191missing. This file has to be installed and patched manually:
wdenkc6097192002-11-03 00:24:07 +00004192
wdenk2729af92004-05-03 20:45:30 +00004193 # cd /usr/pkg/cross/powerpc-netbsd/include
4194 # mkdir powerpc
4195 # ln -s powerpc machine
4196 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
4197 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
wdenkc6097192002-11-03 00:24:07 +00004198
wdenk2729af92004-05-03 20:45:30 +00004199Native builds *don't* work due to incompatibilities between native
4200and U-Boot include files.
wdenkc6097192002-11-03 00:24:07 +00004201
wdenk2729af92004-05-03 20:45:30 +00004202Booting assumes that (the first part of) the image booted is a
4203stage-2 loader which in turn loads and then invokes the kernel
4204proper. Loader sources will eventually appear in the NetBSD source
4205tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
wdenk2a8af182005-04-13 10:02:42 +00004206meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
wdenkc6097192002-11-03 00:24:07 +00004207
4208
wdenk2729af92004-05-03 20:45:30 +00004209Implementation Internals:
4210=========================
wdenkc6097192002-11-03 00:24:07 +00004211
wdenk2729af92004-05-03 20:45:30 +00004212The following is not intended to be a complete description of every
4213implementation detail. However, it should help to understand the
4214inner workings of U-Boot and make it easier to port it to custom
4215hardware.
wdenkc6097192002-11-03 00:24:07 +00004216
4217
wdenk2729af92004-05-03 20:45:30 +00004218Initial Stack, Global Data:
4219---------------------------
wdenkc6097192002-11-03 00:24:07 +00004220
wdenk2729af92004-05-03 20:45:30 +00004221The implementation of U-Boot is complicated by the fact that U-Boot
4222starts running out of ROM (flash memory), usually without access to
4223system RAM (because the memory controller is not initialized yet).
4224This means that we don't have writable Data or BSS segments, and BSS
4225is not initialized as zero. To be able to get a C environment working
4226at all, we have to allocate at least a minimal stack. Implementation
4227options for this are defined and restricted by the CPU used: Some CPU
4228models provide on-chip memory (like the IMMR area on MPC8xx and
4229MPC826x processors), on others (parts of) the data cache can be
4230locked as (mis-) used as memory, etc.
wdenkc6097192002-11-03 00:24:07 +00004231
Wolfgang Denk218ca722008-03-26 10:40:12 +01004232 Chris Hallinan posted a good summary of these issues to the
Wolfgang Denk06682362008-12-30 22:56:11 +01004233 U-Boot mailing list:
wdenk43d96162003-03-06 00:02:04 +00004234
wdenk2729af92004-05-03 20:45:30 +00004235 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
4236 From: "Chris Hallinan" <clh@net1plus.com>
4237 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
4238 ...
wdenk43d96162003-03-06 00:02:04 +00004239
wdenk2729af92004-05-03 20:45:30 +00004240 Correct me if I'm wrong, folks, but the way I understand it
4241 is this: Using DCACHE as initial RAM for Stack, etc, does not
4242 require any physical RAM backing up the cache. The cleverness
4243 is that the cache is being used as a temporary supply of
4244 necessary storage before the SDRAM controller is setup. It's
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02004245 beyond the scope of this list to explain the details, but you
wdenk2729af92004-05-03 20:45:30 +00004246 can see how this works by studying the cache architecture and
4247 operation in the architecture and processor-specific manuals.
wdenk43d96162003-03-06 00:02:04 +00004248
wdenk2729af92004-05-03 20:45:30 +00004249 OCM is On Chip Memory, which I believe the 405GP has 4K. It
4250 is another option for the system designer to use as an
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02004251 initial stack/RAM area prior to SDRAM being available. Either
wdenk2729af92004-05-03 20:45:30 +00004252 option should work for you. Using CS 4 should be fine if your
4253 board designers haven't used it for something that would
4254 cause you grief during the initial boot! It is frequently not
4255 used.
wdenk43d96162003-03-06 00:02:04 +00004256
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02004257 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere
wdenk2729af92004-05-03 20:45:30 +00004258 with your processor/board/system design. The default value
4259 you will find in any recent u-boot distribution in
Stefan Roese8a316c92005-08-01 16:49:12 +02004260 walnut.h should work for you. I'd set it to a value larger
wdenk2729af92004-05-03 20:45:30 +00004261 than your SDRAM module. If you have a 64MB SDRAM module, set
4262 it above 400_0000. Just make sure your board has no resources
4263 that are supposed to respond to that address! That code in
4264 start.S has been around a while and should work as is when
4265 you get the config right.
wdenk43d96162003-03-06 00:02:04 +00004266
wdenk2729af92004-05-03 20:45:30 +00004267 -Chris Hallinan
4268 DS4.COM, Inc.
wdenk43d96162003-03-06 00:02:04 +00004269
wdenk2729af92004-05-03 20:45:30 +00004270It is essential to remember this, since it has some impact on the C
4271code for the initialization procedures:
wdenkc6097192002-11-03 00:24:07 +00004272
wdenk2729af92004-05-03 20:45:30 +00004273* Initialized global data (data segment) is read-only. Do not attempt
4274 to write it.
wdenkc6097192002-11-03 00:24:07 +00004275
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08004276* Do not use any uninitialized global data (or implicitly initialized
wdenk2729af92004-05-03 20:45:30 +00004277 as zero data - BSS segment) at all - this is undefined, initiali-
4278 zation is performed later (when relocating to RAM).
wdenkc6097192002-11-03 00:24:07 +00004279
wdenk2729af92004-05-03 20:45:30 +00004280* Stack space is very limited. Avoid big data buffers or things like
4281 that.
wdenkc6097192002-11-03 00:24:07 +00004282
wdenk2729af92004-05-03 20:45:30 +00004283Having only the stack as writable memory limits means we cannot use
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08004284normal global data to share information between the code. But it
wdenk2729af92004-05-03 20:45:30 +00004285turned out that the implementation of U-Boot can be greatly
4286simplified by making a global data structure (gd_t) available to all
4287functions. We could pass a pointer to this data as argument to _all_
4288functions, but this would bloat the code. Instead we use a feature of
4289the GCC compiler (Global Register Variables) to share the data: we
4290place a pointer (gd) to the global data into a register which we
4291reserve for this purpose.
wdenkc6097192002-11-03 00:24:07 +00004292
wdenk2729af92004-05-03 20:45:30 +00004293When choosing a register for such a purpose we are restricted by the
4294relevant (E)ABI specifications for the current architecture, and by
4295GCC's implementation.
wdenkc6097192002-11-03 00:24:07 +00004296
wdenk2729af92004-05-03 20:45:30 +00004297For PowerPC, the following registers have specific use:
4298 R1: stack pointer
Wolfgang Denke7670f62008-02-14 22:43:22 +01004299 R2: reserved for system use
wdenk2729af92004-05-03 20:45:30 +00004300 R3-R4: parameter passing and return values
4301 R5-R10: parameter passing
4302 R13: small data area pointer
4303 R30: GOT pointer
4304 R31: frame pointer
wdenkc6097192002-11-03 00:24:07 +00004305
Joakim Tjernlunde6bee802010-01-19 14:41:58 +01004306 (U-Boot also uses R12 as internal GOT pointer. r12
4307 is a volatile register so r12 needs to be reset when
4308 going back and forth between asm and C)
wdenkc6097192002-11-03 00:24:07 +00004309
Wolfgang Denke7670f62008-02-14 22:43:22 +01004310 ==> U-Boot will use R2 to hold a pointer to the global data
wdenkc6097192002-11-03 00:24:07 +00004311
wdenk2729af92004-05-03 20:45:30 +00004312 Note: on PPC, we could use a static initializer (since the
4313 address of the global data structure is known at compile time),
4314 but it turned out that reserving a register results in somewhat
4315 smaller code - although the code savings are not that big (on
4316 average for all boards 752 bytes for the whole U-Boot image,
4317 624 text + 127 data).
wdenkc6097192002-11-03 00:24:07 +00004318
wdenk2729af92004-05-03 20:45:30 +00004319On ARM, the following registers are used:
wdenkc6097192002-11-03 00:24:07 +00004320
wdenk2729af92004-05-03 20:45:30 +00004321 R0: function argument word/integer result
4322 R1-R3: function argument word
Jeroen Hofstee12eba1b2013-09-21 14:04:42 +02004323 R9: platform specific
4324 R10: stack limit (used only if stack checking is enabled)
wdenk2729af92004-05-03 20:45:30 +00004325 R11: argument (frame) pointer
4326 R12: temporary workspace
4327 R13: stack pointer
4328 R14: link register
4329 R15: program counter
wdenkc6097192002-11-03 00:24:07 +00004330
Jeroen Hofstee12eba1b2013-09-21 14:04:42 +02004331 ==> U-Boot will use R9 to hold a pointer to the global data
4332
4333 Note: on ARM, only R_ARM_RELATIVE relocations are supported.
wdenkc6097192002-11-03 00:24:07 +00004334
Thomas Chou0df01fd2010-05-21 11:08:03 +08004335On Nios II, the ABI is documented here:
Naoki Hayama047f6ec2020-10-08 13:17:16 +09004336 https://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf
Thomas Chou0df01fd2010-05-21 11:08:03 +08004337
4338 ==> U-Boot will use gp to hold a pointer to the global data
4339
4340 Note: on Nios II, we give "-G0" option to gcc and don't use gp
4341 to access small data sections, so gp is free.
4342
Macpaul Linafc1ce82011-10-19 20:41:11 +00004343On NDS32, the following registers are used:
4344
4345 R0-R1: argument/return
4346 R2-R5: argument
4347 R15: temporary register for assembler
4348 R16: trampoline register
4349 R28: frame pointer (FP)
4350 R29: global pointer (GP)
4351 R30: link register (LP)
4352 R31: stack pointer (SP)
4353 PC: program counter (PC)
4354
4355 ==> U-Boot will use R10 to hold a pointer to the global data
4356
Wolfgang Denkd87080b2006-03-31 18:32:53 +02004357NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
4358or current versions of GCC may "optimize" the code too much.
wdenkc6097192002-11-03 00:24:07 +00004359
Rick Chen3fafced2017-12-26 13:55:59 +08004360On RISC-V, the following registers are used:
4361
4362 x0: hard-wired zero (zero)
4363 x1: return address (ra)
4364 x2: stack pointer (sp)
4365 x3: global pointer (gp)
4366 x4: thread pointer (tp)
4367 x5: link register (t0)
4368 x8: frame pointer (fp)
4369 x10-x11: arguments/return values (a0-1)
4370 x12-x17: arguments (a2-7)
4371 x28-31: temporaries (t3-6)
4372 pc: program counter (pc)
4373
4374 ==> U-Boot will use gp to hold a pointer to the global data
4375
wdenk2729af92004-05-03 20:45:30 +00004376Memory Management:
4377------------------
wdenkc6097192002-11-03 00:24:07 +00004378
wdenk2729af92004-05-03 20:45:30 +00004379U-Boot runs in system state and uses physical addresses, i.e. the
4380MMU is not used either for address mapping nor for memory protection.
wdenkc6097192002-11-03 00:24:07 +00004381
wdenk2729af92004-05-03 20:45:30 +00004382The available memory is mapped to fixed addresses using the memory
4383controller. In this process, a contiguous block is formed for each
4384memory type (Flash, SDRAM, SRAM), even when it consists of several
4385physical memory banks.
wdenkc6097192002-11-03 00:24:07 +00004386
wdenk2729af92004-05-03 20:45:30 +00004387U-Boot is installed in the first 128 kB of the first Flash bank (on
4388TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
4389booting and sizing and initializing DRAM, the code relocates itself
4390to the upper end of DRAM. Immediately below the U-Boot code some
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02004391memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN
wdenk2729af92004-05-03 20:45:30 +00004392configuration setting]. Below that, a structure with global Board
4393Info data is placed, followed by the stack (growing downward).
wdenkc6097192002-11-03 00:24:07 +00004394
wdenk2729af92004-05-03 20:45:30 +00004395Additionally, some exception handler code is copied to the low 8 kB
4396of DRAM (0x00000000 ... 0x00001FFF).
wdenkc6097192002-11-03 00:24:07 +00004397
wdenk2729af92004-05-03 20:45:30 +00004398So a typical memory configuration with 16 MB of DRAM could look like
4399this:
wdenkc6097192002-11-03 00:24:07 +00004400
wdenk2729af92004-05-03 20:45:30 +00004401 0x0000 0000 Exception Vector code
4402 :
4403 0x0000 1FFF
4404 0x0000 2000 Free for Application Use
4405 :
4406 :
wdenkc6097192002-11-03 00:24:07 +00004407
wdenk2729af92004-05-03 20:45:30 +00004408 :
4409 :
4410 0x00FB FF20 Monitor Stack (Growing downward)
4411 0x00FB FFAC Board Info Data and permanent copy of global data
4412 0x00FC 0000 Malloc Arena
4413 :
4414 0x00FD FFFF
4415 0x00FE 0000 RAM Copy of Monitor Code
4416 ... eventually: LCD or video framebuffer
4417 ... eventually: pRAM (Protected RAM - unchanged by reset)
4418 0x00FF FFFF [End of RAM]
wdenkc6097192002-11-03 00:24:07 +00004419
4420
wdenk2729af92004-05-03 20:45:30 +00004421System Initialization:
4422----------------------
wdenkc6097192002-11-03 00:24:07 +00004423
wdenk2729af92004-05-03 20:45:30 +00004424In the reset configuration, U-Boot starts at the reset entry point
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02004425(on most PowerPC systems at address 0x00000100). Because of the reset
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08004426configuration for CS0# this is a mirror of the on board Flash memory.
wdenk2729af92004-05-03 20:45:30 +00004427To be able to re-map memory U-Boot then jumps to its link address.
4428To be able to implement the initialization code in C, a (small!)
4429initial stack is set up in the internal Dual Ported RAM (in case CPUs
Heiko Schocher2eb48ff2017-06-07 17:33:10 +02004430which provide such a feature like), or in a locked part of the data
4431cache. After that, U-Boot initializes the CPU core, the caches and
4432the SIU.
wdenkc6097192002-11-03 00:24:07 +00004433
wdenk2729af92004-05-03 20:45:30 +00004434Next, all (potentially) available memory banks are mapped using a
4435preliminary mapping. For example, we put them on 512 MB boundaries
4436(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
4437on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
4438programmed for SDRAM access. Using the temporary configuration, a
4439simple memory test is run that determines the size of the SDRAM
4440banks.
wdenkc6097192002-11-03 00:24:07 +00004441
wdenk2729af92004-05-03 20:45:30 +00004442When there is more than one SDRAM bank, and the banks are of
4443different size, the largest is mapped first. For equal size, the first
4444bank (CS2#) is mapped first. The first mapping is always for address
44450x00000000, with any additional banks following immediately to create
4446contiguous memory starting from 0.
wdenkc6097192002-11-03 00:24:07 +00004447
wdenk2729af92004-05-03 20:45:30 +00004448Then, the monitor installs itself at the upper end of the SDRAM area
4449and allocates memory for use by malloc() and for the global Board
4450Info data; also, the exception vector code is copied to the low RAM
4451pages, and the final stack is set up.
wdenkc6097192002-11-03 00:24:07 +00004452
wdenk2729af92004-05-03 20:45:30 +00004453Only after this relocation will you have a "normal" C environment;
4454until that you are restricted in several ways, mostly because you are
4455running from ROM, and because the code will have to be relocated to a
4456new address in RAM.
wdenkc6097192002-11-03 00:24:07 +00004457
4458
wdenk2729af92004-05-03 20:45:30 +00004459U-Boot Porting Guide:
4460----------------------
wdenkc6097192002-11-03 00:24:07 +00004461
wdenk2729af92004-05-03 20:45:30 +00004462[Based on messages by Jerry Van Baren in the U-Boot-Users mailing
4463list, October 2002]
wdenkc6097192002-11-03 00:24:07 +00004464
4465
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04004466int main(int argc, char *argv[])
wdenk2729af92004-05-03 20:45:30 +00004467{
4468 sighandler_t no_more_time;
wdenkc6097192002-11-03 00:24:07 +00004469
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04004470 signal(SIGALRM, no_more_time);
4471 alarm(PROJECT_DEADLINE - toSec (3 * WEEK));
wdenkc6097192002-11-03 00:24:07 +00004472
wdenk2729af92004-05-03 20:45:30 +00004473 if (available_money > available_manpower) {
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04004474 Pay consultant to port U-Boot;
wdenkc6097192002-11-03 00:24:07 +00004475 return 0;
4476 }
4477
wdenk2729af92004-05-03 20:45:30 +00004478 Download latest U-Boot source;
4479
Wolfgang Denk06682362008-12-30 22:56:11 +01004480 Subscribe to u-boot mailing list;
wdenk2729af92004-05-03 20:45:30 +00004481
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04004482 if (clueless)
4483 email("Hi, I am new to U-Boot, how do I get started?");
wdenkc6097192002-11-03 00:24:07 +00004484
wdenk2729af92004-05-03 20:45:30 +00004485 while (learning) {
4486 Read the README file in the top level directory;
Naoki Hayama047f6ec2020-10-08 13:17:16 +09004487 Read https://www.denx.de/wiki/bin/view/DULG/Manual;
Patrick Delaunay24bcaec2020-02-28 15:18:10 +01004488 Read applicable doc/README.*;
wdenk2729af92004-05-03 20:45:30 +00004489 Read the source, Luke;
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04004490 /* find . -name "*.[chS]" | xargs grep -i <keyword> */
wdenk2729af92004-05-03 20:45:30 +00004491 }
wdenkc6097192002-11-03 00:24:07 +00004492
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04004493 if (available_money > toLocalCurrency ($2500))
4494 Buy a BDI3000;
4495 else
wdenk2729af92004-05-03 20:45:30 +00004496 Add a lot of aggravation and time;
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04004497
4498 if (a similar board exists) { /* hopefully... */
4499 cp -a board/<similar> board/<myboard>
4500 cp include/configs/<similar>.h include/configs/<myboard>.h
4501 } else {
4502 Create your own board support subdirectory;
4503 Create your own board include/configs/<myboard>.h file;
wdenk2729af92004-05-03 20:45:30 +00004504 }
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04004505 Edit new board/<myboard> files
4506 Edit new include/configs/<myboard>.h
wdenkc6097192002-11-03 00:24:07 +00004507
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04004508 while (!accepted) {
4509 while (!running) {
4510 do {
4511 Add / modify source code;
4512 } until (compiles);
4513 Debug;
4514 if (clueless)
4515 email("Hi, I am having problems...");
4516 }
4517 Send patch file to the U-Boot email list;
4518 if (reasonable critiques)
4519 Incorporate improvements from email list code review;
4520 else
4521 Defend code as written;
wdenk2729af92004-05-03 20:45:30 +00004522 }
wdenkc6097192002-11-03 00:24:07 +00004523
wdenk2729af92004-05-03 20:45:30 +00004524 return 0;
4525}
4526
4527void no_more_time (int sig)
4528{
4529 hire_a_guru();
4530}
wdenkc6097192002-11-03 00:24:07 +00004531
4532
wdenk2729af92004-05-03 20:45:30 +00004533Coding Standards:
4534-----------------
wdenkc6097192002-11-03 00:24:07 +00004535
wdenk2729af92004-05-03 20:45:30 +00004536All contributions to U-Boot should conform to the Linux kernel
Baruch Siach659208d2017-12-10 17:34:35 +02004537coding style; see the kernel coding style guide at
4538https://www.kernel.org/doc/html/latest/process/coding-style.html, and the
4539script "scripts/Lindent" in your Linux kernel source directory.
wdenk2729af92004-05-03 20:45:30 +00004540
Detlev Zundel2c051652006-09-01 15:39:02 +02004541Source files originating from a different project (for example the
4542MTD subsystem) are generally exempt from these guidelines and are not
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08004543reformatted to ease subsequent migration to newer versions of those
Detlev Zundel2c051652006-09-01 15:39:02 +02004544sources.
4545
4546Please note that U-Boot is implemented in C (and to some small parts in
4547Assembler); no C++ is used, so please do not use C++ style comments (//)
4548in your code.
wdenk2729af92004-05-03 20:45:30 +00004549
4550Please also stick to the following formatting rules:
4551- remove any trailing white space
Wolfgang Denk7ca92962011-07-27 10:59:55 +00004552- use TAB characters for indentation and vertical alignment, not spaces
wdenk2729af92004-05-03 20:45:30 +00004553- make sure NOT to use DOS '\r\n' line feeds
Wolfgang Denk7ca92962011-07-27 10:59:55 +00004554- do not add more than 2 consecutive empty lines to source files
wdenk2729af92004-05-03 20:45:30 +00004555- do not add trailing empty lines to source files
4556
4557Submissions which do not conform to the standards may be returned
4558with a request to reformat the changes.
wdenkc6097192002-11-03 00:24:07 +00004559
4560
wdenk2729af92004-05-03 20:45:30 +00004561Submitting Patches:
4562-------------------
wdenkc6097192002-11-03 00:24:07 +00004563
wdenk2729af92004-05-03 20:45:30 +00004564Since the number of patches for U-Boot is growing, we need to
4565establish some rules. Submissions which do not conform to these rules
4566may be rejected, even when they contain important and valuable stuff.
wdenkc6097192002-11-03 00:24:07 +00004567
Naoki Hayama047f6ec2020-10-08 13:17:16 +09004568Please see https://www.denx.de/wiki/U-Boot/Patches for details.
Wolfgang Denk218ca722008-03-26 10:40:12 +01004569
Wolfgang Denk06682362008-12-30 22:56:11 +01004570Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>;
S. Lockwood-Childs1dade182017-11-14 22:56:42 -08004571see https://lists.denx.de/listinfo/u-boot
Wolfgang Denk06682362008-12-30 22:56:11 +01004572
wdenk2729af92004-05-03 20:45:30 +00004573When you send a patch, please include the following information with
4574it:
wdenkc6097192002-11-03 00:24:07 +00004575
wdenk2729af92004-05-03 20:45:30 +00004576* For bug fixes: a description of the bug and how your patch fixes
4577 this bug. Please try to include a way of demonstrating that the
4578 patch actually fixes something.
wdenkc6097192002-11-03 00:24:07 +00004579
wdenk2729af92004-05-03 20:45:30 +00004580* For new features: a description of the feature and your
4581 implementation.
wdenkc6097192002-11-03 00:24:07 +00004582
Robert P. J. Day7207b362015-12-19 07:16:10 -05004583* For major contributions, add a MAINTAINERS file with your
4584 information and associated file and directory references.
wdenk2729af92004-05-03 20:45:30 +00004585
Albert ARIBAUD27af9302013-09-11 15:52:51 +02004586* When you add support for a new board, don't forget to add a
4587 maintainer e-mail address to the boards.cfg file, too.
wdenk2729af92004-05-03 20:45:30 +00004588
4589* If your patch adds new configuration options, don't forget to
4590 document these in the README file.
4591
Wolfgang Denk218ca722008-03-26 10:40:12 +01004592* The patch itself. If you are using git (which is *strongly*
4593 recommended) you can easily generate the patch using the
Wolfgang Denk7ca92962011-07-27 10:59:55 +00004594 "git format-patch". If you then use "git send-email" to send it to
Wolfgang Denk218ca722008-03-26 10:40:12 +01004595 the U-Boot mailing list, you will avoid most of the common problems
4596 with some other mail clients.
wdenk2729af92004-05-03 20:45:30 +00004597
Wolfgang Denk218ca722008-03-26 10:40:12 +01004598 If you cannot use git, use "diff -purN OLD NEW". If your version of
4599 diff does not support these options, then get the latest version of
4600 GNU diff.
wdenk2729af92004-05-03 20:45:30 +00004601
Wolfgang Denk218ca722008-03-26 10:40:12 +01004602 The current directory when running this command shall be the parent
4603 directory of the U-Boot source tree (i. e. please make sure that
4604 your patch includes sufficient directory information for the
4605 affected files).
4606
4607 We prefer patches as plain text. MIME attachments are discouraged,
4608 and compressed attachments must not be used.
wdenk2729af92004-05-03 20:45:30 +00004609
4610* If one logical set of modifications affects or creates several
4611 files, all these changes shall be submitted in a SINGLE patch file.
4612
4613* Changesets that contain different, unrelated modifications shall be
4614 submitted as SEPARATE patches, one patch per changeset.
4615
4616
4617Notes:
4618
Simon Glass6de80f22016-07-27 20:33:08 -06004619* Before sending the patch, run the buildman script on your patched
wdenk2729af92004-05-03 20:45:30 +00004620 source tree and make sure that no errors or warnings are reported
4621 for any of the boards.
4622
4623* Keep your modifications to the necessary minimum: A patch
4624 containing several unrelated changes or arbitrary reformats will be
4625 returned with a request to re-formatting / split it.
4626
4627* If you modify existing code, make sure that your new code does not
4628 add to the memory footprint of the code ;-) Small is beautiful!
4629 When adding new features, these should compile conditionally only
4630 (using #ifdef), and the resulting code with the new feature
4631 disabled must not need more memory than the old code without your
4632 modification.
wdenk90dc6702005-05-03 14:12:25 +00004633
Wolfgang Denk06682362008-12-30 22:56:11 +01004634* Remember that there is a size limit of 100 kB per message on the
4635 u-boot mailing list. Bigger patches will be moderated. If they are
4636 reasonable and not too big, they will be acknowledged. But patches
4637 bigger than the size limit should be avoided.