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Tom Rini83d290c2018-05-06 17:58:06 -04001# SPDX-License-Identifier: GPL-2.0+
wdenkc6097192002-11-03 00:24:07 +00002#
Wolfgang Denkeca3aeb2013-06-21 10:22:36 +02003# (C) Copyright 2000 - 2013
wdenkc6097192002-11-03 00:24:07 +00004# Wolfgang Denk, DENX Software Engineering, wd@denx.de.
wdenkc6097192002-11-03 00:24:07 +00005
6Summary:
7========
8
wdenk24ee89b2002-11-03 17:56:27 +00009This directory contains the source code for U-Boot, a boot loader for
wdenke86e5a02004-10-17 21:12:06 +000010Embedded boards based on PowerPC, ARM, MIPS and several other
11processors, which can be installed in a boot ROM and used to
12initialize and test the hardware or to download and run application
13code.
wdenkc6097192002-11-03 00:24:07 +000014
15The development of U-Boot is closely related to Linux: some parts of
wdenk24ee89b2002-11-03 17:56:27 +000016the source code originate in the Linux source tree, we have some
17header files in common, and special provision has been made to
wdenkc6097192002-11-03 00:24:07 +000018support booting of Linux images.
19
20Some attention has been paid to make this software easily
21configurable and extendable. For instance, all monitor commands are
22implemented with the same call interface, so that it's very easy to
23add new commands. Also, instead of permanently adding rarely used
24code (for instance hardware test utilities) to the monitor, you can
25load and run it dynamically.
26
27
28Status:
29=======
30
31In general, all boards for which a configuration option exists in the
wdenk24ee89b2002-11-03 17:56:27 +000032Makefile have been tested to some extent and can be considered
wdenkc6097192002-11-03 00:24:07 +000033"working". In fact, many of them are used in production systems.
34
Robert P. J. Day7207b362015-12-19 07:16:10 -050035In case of problems see the CHANGELOG file to find out who contributed
36the specific port. In addition, there are various MAINTAINERS files
37scattered throughout the U-Boot source identifying the people or
38companies responsible for various boards and subsystems.
wdenkc6097192002-11-03 00:24:07 +000039
Robert P. J. Day7207b362015-12-19 07:16:10 -050040Note: As of August, 2010, there is no longer a CHANGELOG file in the
41actual U-Boot source tree; however, it can be created dynamically
42from the Git log using:
Robert P. J. Dayadb9d852012-11-14 02:03:20 +000043
44 make CHANGELOG
45
wdenkc6097192002-11-03 00:24:07 +000046
47Where to get help:
48==================
49
wdenk24ee89b2002-11-03 17:56:27 +000050In case you have questions about, problems with or contributions for
Robert P. J. Day7207b362015-12-19 07:16:10 -050051U-Boot, you should send a message to the U-Boot mailing list at
Peter Tyser0c325652008-09-10 09:18:34 -050052<u-boot@lists.denx.de>. There is also an archive of previous traffic
53on the mailing list - please search the archive before asking FAQ's.
54Please see http://lists.denx.de/pipermail/u-boot and
55http://dir.gmane.org/gmane.comp.boot-loaders.u-boot
wdenkc6097192002-11-03 00:24:07 +000056
57
Wolfgang Denk218ca722008-03-26 10:40:12 +010058Where to get source code:
59=========================
60
Robert P. J. Day7207b362015-12-19 07:16:10 -050061The U-Boot source code is maintained in the Git repository at
Wolfgang Denk218ca722008-03-26 10:40:12 +010062git://www.denx.de/git/u-boot.git ; you can browse it online at
63http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary
64
65The "snapshot" links on this page allow you to download tarballs of
Marcel Ziswiler11ccc332008-07-09 08:17:15 +020066any version you might be interested in. Official releases are also
Wolfgang Denk218ca722008-03-26 10:40:12 +010067available for FTP download from the ftp://ftp.denx.de/pub/u-boot/
68directory.
69
Anatolij Gustschind4ee7112008-03-26 18:13:33 +010070Pre-built (and tested) images are available from
Wolfgang Denk218ca722008-03-26 10:40:12 +010071ftp://ftp.denx.de/pub/u-boot/images/
72
73
wdenkc6097192002-11-03 00:24:07 +000074Where we come from:
75===================
76
77- start from 8xxrom sources
wdenk24ee89b2002-11-03 17:56:27 +000078- create PPCBoot project (http://sourceforge.net/projects/ppcboot)
wdenkc6097192002-11-03 00:24:07 +000079- clean up code
80- make it easier to add custom boards
81- make it possible to add other [PowerPC] CPUs
82- extend functions, especially:
83 * Provide extended interface to Linux boot loader
84 * S-Record download
85 * network boot
Marcel Ziswiler11ccc332008-07-09 08:17:15 +020086 * PCMCIA / CompactFlash / ATA disk / SCSI ... boot
wdenk24ee89b2002-11-03 17:56:27 +000087- create ARMBoot project (http://sourceforge.net/projects/armboot)
wdenkc6097192002-11-03 00:24:07 +000088- add other CPU families (starting with ARM)
wdenk24ee89b2002-11-03 17:56:27 +000089- create U-Boot project (http://sourceforge.net/projects/u-boot)
Magnus Lilja0d28f342008-08-06 19:32:33 +020090- current project page: see http://www.denx.de/wiki/U-Boot
wdenk24ee89b2002-11-03 17:56:27 +000091
92
93Names and Spelling:
94===================
95
96The "official" name of this project is "Das U-Boot". The spelling
97"U-Boot" shall be used in all written text (documentation, comments
98in source files etc.). Example:
99
100 This is the README file for the U-Boot project.
101
102File names etc. shall be based on the string "u-boot". Examples:
103
104 include/asm-ppc/u-boot.h
105
106 #include <asm/u-boot.h>
107
108Variable names, preprocessor constants etc. shall be either based on
109the string "u_boot" or on "U_BOOT". Example:
110
111 U_BOOT_VERSION u_boot_logo
112 IH_OS_U_BOOT u_boot_hush_start
wdenkc6097192002-11-03 00:24:07 +0000113
114
wdenk93f19cc2002-12-17 17:55:09 +0000115Versioning:
116===========
117
Thomas Weber360d8832010-09-28 08:06:25 +0200118Starting with the release in October 2008, the names of the releases
119were changed from numerical release numbers without deeper meaning
120into a time stamp based numbering. Regular releases are identified by
121names consisting of the calendar year and month of the release date.
122Additional fields (if present) indicate release candidates or bug fix
123releases in "stable" maintenance trees.
wdenk93f19cc2002-12-17 17:55:09 +0000124
Thomas Weber360d8832010-09-28 08:06:25 +0200125Examples:
Wolfgang Denkc0f40852011-10-26 10:21:21 +0000126 U-Boot v2009.11 - Release November 2009
Thomas Weber360d8832010-09-28 08:06:25 +0200127 U-Boot v2009.11.1 - Release 1 in version November 2009 stable tree
Jelle van der Waa0de21ec2016-10-30 17:30:30 +0100128 U-Boot v2010.09-rc1 - Release candidate 1 for September 2010 release
wdenk93f19cc2002-12-17 17:55:09 +0000129
130
wdenkc6097192002-11-03 00:24:07 +0000131Directory Hierarchy:
132====================
133
Peter Tyser8d321b82010-04-12 22:28:21 -0500134/arch Architecture specific files
Masahiro Yamada6eae68e2014-03-07 18:02:02 +0900135 /arc Files generic to ARC architecture
Peter Tyser8d321b82010-04-12 22:28:21 -0500136 /arm Files generic to ARM architecture
Peter Tyser8d321b82010-04-12 22:28:21 -0500137 /m68k Files generic to m68k architecture
Peter Tyser8d321b82010-04-12 22:28:21 -0500138 /microblaze Files generic to microblaze architecture
Peter Tyser8d321b82010-04-12 22:28:21 -0500139 /mips Files generic to MIPS architecture
Macpaul Linafc1ce82011-10-19 20:41:11 +0000140 /nds32 Files generic to NDS32 architecture
Peter Tyser8d321b82010-04-12 22:28:21 -0500141 /nios2 Files generic to Altera NIOS2 architecture
Robert P. J. Day33c77312013-09-15 18:34:15 -0400142 /openrisc Files generic to OpenRISC architecture
Stefan Roesea47a12b2010-04-15 16:07:28 +0200143 /powerpc Files generic to PowerPC architecture
Rick Chen3fafced2017-12-26 13:55:59 +0800144 /riscv Files generic to RISC-V architecture
Robert P. J. Day7207b362015-12-19 07:16:10 -0500145 /sandbox Files generic to HW-independent "sandbox"
Peter Tyser8d321b82010-04-12 22:28:21 -0500146 /sh Files generic to SH architecture
Robert P. J. Day33c77312013-09-15 18:34:15 -0400147 /x86 Files generic to x86 architecture
Peter Tyser8d321b82010-04-12 22:28:21 -0500148/api Machine/arch independent API for external apps
149/board Board dependent files
Xu Ziyuan740f7e52016-08-26 19:54:49 +0800150/cmd U-Boot commands functions
Peter Tyser8d321b82010-04-12 22:28:21 -0500151/common Misc architecture independent functions
Robert P. J. Day7207b362015-12-19 07:16:10 -0500152/configs Board default configuration files
Peter Tyser8d321b82010-04-12 22:28:21 -0500153/disk Code for disk drive partition handling
154/doc Documentation (don't expect too much)
155/drivers Commonly used device drivers
Robert P. J. Day33c77312013-09-15 18:34:15 -0400156/dts Contains Makefile for building internal U-Boot fdt.
Peter Tyser8d321b82010-04-12 22:28:21 -0500157/examples Example code for standalone applications, etc.
158/fs Filesystem code (cramfs, ext2, jffs2, etc.)
159/include Header Files
Robert P. J. Day7207b362015-12-19 07:16:10 -0500160/lib Library routines generic to all architectures
161/Licenses Various license files
Peter Tyser8d321b82010-04-12 22:28:21 -0500162/net Networking code
163/post Power On Self Test
Robert P. J. Day7207b362015-12-19 07:16:10 -0500164/scripts Various build scripts and Makefiles
165/test Various unit test files
Peter Tyser8d321b82010-04-12 22:28:21 -0500166/tools Tools to build S-Record or U-Boot images, etc.
wdenkc6097192002-11-03 00:24:07 +0000167
wdenkc6097192002-11-03 00:24:07 +0000168Software Configuration:
169=======================
170
171Configuration is usually done using C preprocessor defines; the
172rationale behind that is to avoid dead code whenever possible.
173
174There are two classes of configuration variables:
175
176* Configuration _OPTIONS_:
177 These are selectable by the user and have names beginning with
178 "CONFIG_".
179
180* Configuration _SETTINGS_:
181 These depend on the hardware etc. and should not be meddled with if
182 you don't know what you're doing; they have names beginning with
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +0200183 "CONFIG_SYS_".
wdenkc6097192002-11-03 00:24:07 +0000184
Robert P. J. Day7207b362015-12-19 07:16:10 -0500185Previously, all configuration was done by hand, which involved creating
186symbolic links and editing configuration files manually. More recently,
187U-Boot has added the Kbuild infrastructure used by the Linux kernel,
188allowing you to use the "make menuconfig" command to configure your
189build.
wdenkc6097192002-11-03 00:24:07 +0000190
191
192Selection of Processor Architecture and Board Type:
193---------------------------------------------------
194
195For all supported boards there are ready-to-use default
Holger Freytherab584d62014-08-04 09:26:05 +0200196configurations available; just type "make <board_name>_defconfig".
wdenkc6097192002-11-03 00:24:07 +0000197
198Example: For a TQM823L module type:
199
200 cd u-boot
Holger Freytherab584d62014-08-04 09:26:05 +0200201 make TQM823L_defconfig
wdenkc6097192002-11-03 00:24:07 +0000202
Robert P. J. Day7207b362015-12-19 07:16:10 -0500203Note: If you're looking for the default configuration file for a board
204you're sure used to be there but is now missing, check the file
205doc/README.scrapyard for a list of no longer supported boards.
wdenkc6097192002-11-03 00:24:07 +0000206
Simon Glass75b3c3a2014-03-22 17:12:59 -0600207Sandbox Environment:
208--------------------
209
210U-Boot can be built natively to run on a Linux host using the 'sandbox'
211board. This allows feature development which is not board- or architecture-
212specific to be undertaken on a native platform. The sandbox is also used to
213run some of U-Boot's tests.
214
Jagannadha Sutradharudu Teki6b1978f2014-08-31 21:19:43 +0530215See board/sandbox/README.sandbox for more details.
Simon Glass75b3c3a2014-03-22 17:12:59 -0600216
217
Simon Glassdb910352015-03-03 08:03:00 -0700218Board Initialisation Flow:
219--------------------------
220
221This is the intended start-up flow for boards. This should apply for both
Robert P. J. Day7207b362015-12-19 07:16:10 -0500222SPL and U-Boot proper (i.e. they both follow the same rules).
Simon Glassdb910352015-03-03 08:03:00 -0700223
Robert P. J. Day7207b362015-12-19 07:16:10 -0500224Note: "SPL" stands for "Secondary Program Loader," which is explained in
225more detail later in this file.
226
227At present, SPL mostly uses a separate code path, but the function names
228and roles of each function are the same. Some boards or architectures
229may not conform to this. At least most ARM boards which use
230CONFIG_SPL_FRAMEWORK conform to this.
231
232Execution typically starts with an architecture-specific (and possibly
233CPU-specific) start.S file, such as:
234
235 - arch/arm/cpu/armv7/start.S
236 - arch/powerpc/cpu/mpc83xx/start.S
237 - arch/mips/cpu/start.S
238
239and so on. From there, three functions are called; the purpose and
240limitations of each of these functions are described below.
Simon Glassdb910352015-03-03 08:03:00 -0700241
242lowlevel_init():
243 - purpose: essential init to permit execution to reach board_init_f()
244 - no global_data or BSS
245 - there is no stack (ARMv7 may have one but it will soon be removed)
246 - must not set up SDRAM or use console
247 - must only do the bare minimum to allow execution to continue to
248 board_init_f()
249 - this is almost never needed
250 - return normally from this function
251
252board_init_f():
253 - purpose: set up the machine ready for running board_init_r():
254 i.e. SDRAM and serial UART
255 - global_data is available
256 - stack is in SRAM
257 - BSS is not available, so you cannot use global/static variables,
258 only stack variables and global_data
259
260 Non-SPL-specific notes:
261 - dram_init() is called to set up DRAM. If already done in SPL this
262 can do nothing
263
264 SPL-specific notes:
265 - you can override the entire board_init_f() function with your own
266 version as needed.
267 - preloader_console_init() can be called here in extremis
268 - should set up SDRAM, and anything needed to make the UART work
269 - these is no need to clear BSS, it will be done by crt0.S
270 - must return normally from this function (don't call board_init_r()
271 directly)
272
273Here the BSS is cleared. For SPL, if CONFIG_SPL_STACK_R is defined, then at
274this point the stack and global_data are relocated to below
275CONFIG_SPL_STACK_R_ADDR. For non-SPL, U-Boot is relocated to run at the top of
276memory.
277
278board_init_r():
279 - purpose: main execution, common code
280 - global_data is available
281 - SDRAM is available
282 - BSS is available, all static/global variables can be used
283 - execution eventually continues to main_loop()
284
285 Non-SPL-specific notes:
286 - U-Boot is relocated to the top of memory and is now running from
287 there.
288
289 SPL-specific notes:
290 - stack is optionally in SDRAM, if CONFIG_SPL_STACK_R is defined and
291 CONFIG_SPL_STACK_R_ADDR points into SDRAM
292 - preloader_console_init() can be called here - typically this is
Ley Foon Tan0680f1b2017-05-03 17:13:32 +0800293 done by selecting CONFIG_SPL_BOARD_INIT and then supplying a
Simon Glassdb910352015-03-03 08:03:00 -0700294 spl_board_init() function containing this call
295 - loads U-Boot or (in falcon mode) Linux
296
297
298
wdenkc6097192002-11-03 00:24:07 +0000299Configuration Options:
300----------------------
301
302Configuration depends on the combination of board and CPU type; all
303such information is kept in a configuration file
304"include/configs/<board_name>.h".
305
306Example: For a TQM823L module, all configuration settings are in
307"include/configs/TQM823L.h".
308
309
wdenk7f6c2cb2002-11-10 22:06:23 +0000310Many of the options are named exactly as the corresponding Linux
311kernel configuration options. The intention is to make it easier to
312build a config tool - later.
313
Ashish Kumar63b23162017-08-11 11:09:14 +0530314- ARM Platform Bus Type(CCI):
315 CoreLink Cache Coherent Interconnect (CCI) is ARM BUS which
316 provides full cache coherency between two clusters of multi-core
317 CPUs and I/O coherency for devices and I/O masters
318
319 CONFIG_SYS_FSL_HAS_CCI400
320
321 Defined For SoC that has cache coherent interconnect
322 CCN-400
wdenk7f6c2cb2002-11-10 22:06:23 +0000323
Ashish Kumarc055cee2017-08-18 10:54:36 +0530324 CONFIG_SYS_FSL_HAS_CCN504
325
326 Defined for SoC that has cache coherent interconnect CCN-504
327
wdenkc6097192002-11-03 00:24:07 +0000328The following options need to be configured:
329
Kim Phillips26281142007-08-10 13:28:25 -0500330- CPU Type: Define exactly one, e.g. CONFIG_MPC85XX.
wdenkc6097192002-11-03 00:24:07 +0000331
Kim Phillips26281142007-08-10 13:28:25 -0500332- Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS.
Wolfgang Denk6ccec442006-10-24 14:42:37 +0200333
Lei Wencf946c62011-02-09 18:06:58 +0530334- Marvell Family Member
335 CONFIG_SYS_MVFS - define it if you want to enable
336 multiple fs option at one time
337 for marvell soc family
338
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
Prabhakar Kushwaha89ad7be2014-04-08 19:13:34 +0530494 CONFIG_SPL_FSL_PBL
495 It adds a target to create boot binary having SPL binary in PBI format
496 concatenated with u-boot binary.
497
York Sun4e5b1bd2014-02-10 13:59:42 -0800498 CONFIG_SYS_FSL_DDR_BE
499 Defines the DDR controller register space as Big Endian
500
501 CONFIG_SYS_FSL_DDR_LE
502 Defines the DDR controller register space as Little Endian
503
York Sun6b9e3092014-02-10 13:59:43 -0800504 CONFIG_SYS_FSL_DDR_SDRAM_BASE_PHY
505 Physical address from the view of DDR controllers. It is the
506 same as CONFIG_SYS_DDR_SDRAM_BASE for all Power SoCs. But
507 it could be different for ARM SoCs.
508
York Sun6b1e1252014-02-10 13:59:44 -0800509 CONFIG_SYS_FSL_DDR_INTLV_256B
510 DDR controller interleaving on 256-byte. This is a special
511 interleaving mode, handled by Dickens for Freescale layerscape
512 SoCs with ARM core.
513
York Sun1d71efb2014-08-01 15:51:00 -0700514 CONFIG_SYS_FSL_DDR_MAIN_NUM_CTRLS
515 Number of controllers used as main memory.
516
517 CONFIG_SYS_FSL_OTHER_DDR_NUM_CTRLS
518 Number of controllers used for other than main memory.
519
Prabhakar Kushwaha44937212015-11-09 16:42:07 +0530520 CONFIG_SYS_FSL_HAS_DP_DDR
521 Defines the SoC has DP-DDR used for DPAA.
522
Ruchika Gupta028dbb82014-09-09 11:50:31 +0530523 CONFIG_SYS_FSL_SEC_BE
524 Defines the SEC controller register space as Big Endian
525
526 CONFIG_SYS_FSL_SEC_LE
527 Defines the SEC controller register space as Little Endian
528
Daniel Schwierzeck92bbd642011-07-27 13:22:39 +0200529- MIPS CPU options:
530 CONFIG_SYS_INIT_SP_OFFSET
531
532 Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack
533 pointer. This is needed for the temporary stack before
534 relocation.
535
536 CONFIG_SYS_MIPS_CACHE_MODE
537
538 Cache operation mode for the MIPS CPU.
539 See also arch/mips/include/asm/mipsregs.h.
540 Possible values are:
541 CONF_CM_CACHABLE_NO_WA
542 CONF_CM_CACHABLE_WA
543 CONF_CM_UNCACHED
544 CONF_CM_CACHABLE_NONCOHERENT
545 CONF_CM_CACHABLE_CE
546 CONF_CM_CACHABLE_COW
547 CONF_CM_CACHABLE_CUW
548 CONF_CM_CACHABLE_ACCELERATED
549
550 CONFIG_SYS_XWAY_EBU_BOOTCFG
551
552 Special option for Lantiq XWAY SoCs for booting from NOR flash.
553 See also arch/mips/cpu/mips32/start.S.
554
555 CONFIG_XWAY_SWAP_BYTES
556
557 Enable compilation of tools/xway-swap-bytes needed for Lantiq
558 XWAY SoCs for booting from NOR flash. The U-Boot image needs to
559 be swapped if a flash programmer is used.
560
Christian Rieschb67d8812012-02-02 00:44:39 +0000561- ARM options:
562 CONFIG_SYS_EXCEPTION_VECTORS_HIGH
563
564 Select high exception vectors of the ARM core, e.g., do not
565 clear the V bit of the c1 register of CP15.
566
York Sun207774b2015-03-20 19:28:08 -0700567 COUNTER_FREQUENCY
568 Generic timer clock source frequency.
569
570 COUNTER_FREQUENCY_REAL
571 Generic timer clock source frequency if the real clock is
572 different from COUNTER_FREQUENCY, and can only be determined
573 at run time.
574
Stephen Warren73c38932015-01-19 16:25:52 -0700575- Tegra SoC options:
576 CONFIG_TEGRA_SUPPORT_NON_SECURE
577
578 Support executing U-Boot in non-secure (NS) mode. Certain
579 impossible actions will be skipped if the CPU is in NS mode,
580 such as ARM architectural timer initialization.
581
wdenk5da627a2003-10-09 20:09:04 +0000582- Linux Kernel Interface:
wdenkc6097192002-11-03 00:24:07 +0000583 CONFIG_CLOCKS_IN_MHZ
584
585 U-Boot stores all clock information in Hz
586 internally. For binary compatibility with older Linux
587 kernels (which expect the clocks passed in the
588 bd_info data to be in MHz) the environment variable
589 "clocks_in_mhz" can be defined so that U-Boot
590 converts clock data to MHZ before passing it to the
591 Linux kernel.
wdenkc6097192002-11-03 00:24:07 +0000592 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
Wolfgang Denk218ca722008-03-26 10:40:12 +0100593 "clocks_in_mhz=1" is automatically included in the
wdenkc6097192002-11-03 00:24:07 +0000594 default environment.
595
wdenk5da627a2003-10-09 20:09:04 +0000596 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
597
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -0800598 When transferring memsize parameter to Linux, some versions
wdenk5da627a2003-10-09 20:09:04 +0000599 expect it to be in bytes, others in MB.
600 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
601
Gerald Van Barenfec6d9e2008-06-03 20:34:45 -0400602 CONFIG_OF_LIBFDT
Wolfgang Denkf57f70a2005-10-13 01:45:54 +0200603
604 New kernel versions are expecting firmware settings to be
Gerald Van Baren213bf8c2007-03-31 12:23:51 -0400605 passed using flattened device trees (based on open firmware
606 concepts).
607
608 CONFIG_OF_LIBFDT
609 * New libfdt-based support
610 * Adds the "fdt" command
Kim Phillips3bb342f2007-08-10 14:34:14 -0500611 * The bootm command automatically updates the fdt
Gerald Van Baren213bf8c2007-03-31 12:23:51 -0400612
Wolfgang Denkf57f70a2005-10-13 01:45:54 +0200613 OF_TBCLK - The timebase frequency.
Kumar Galac2871f02006-01-11 13:59:02 -0600614 OF_STDOUT_PATH - The path to the console device
Wolfgang Denkf57f70a2005-10-13 01:45:54 +0200615
Marcel Ziswiler11ccc332008-07-09 08:17:15 +0200616 boards with QUICC Engines require OF_QE to set UCC MAC
617 addresses
Kim Phillips3bb342f2007-08-10 14:34:14 -0500618
Kumar Gala4e253132006-01-11 13:54:17 -0600619 CONFIG_OF_BOARD_SETUP
620
621 Board code has addition modification that it wants to make
622 to the flat device tree before handing it off to the kernel
wdenk6705d812004-08-02 23:22:59 +0000623
Simon Glassc654b512014-10-23 18:58:54 -0600624 CONFIG_OF_SYSTEM_SETUP
625
626 Other code has addition modification that it wants to make
627 to the flat device tree before handing it off to the kernel.
628 This causes ft_system_setup() to be called before booting
629 the kernel.
630
Heiko Schocher3887c3f2009-09-23 07:56:08 +0200631 CONFIG_OF_IDE_FIXUP
632
633 U-Boot can detect if an IDE device is present or not.
634 If not, and this new config option is activated, U-Boot
635 removes the ATA node from the DTS before booting Linux,
636 so the Linux IDE driver does not probe the device and
637 crash. This is needed for buggy hardware (uc101) where
638 no pull down resistor is connected to the signal IDE5V_DD7.
639
Igor Grinberg7eb29392011-07-14 05:45:07 +0000640 CONFIG_MACH_TYPE [relevant for ARM only][mandatory]
641
642 This setting is mandatory for all boards that have only one
643 machine type and must be used to specify the machine type
644 number as it appears in the ARM machine registry
645 (see http://www.arm.linux.org.uk/developer/machines/).
646 Only boards that have multiple machine types supported
647 in a single configuration file and the machine type is
648 runtime discoverable, do not have to use this setting.
649
Niklaus Giger0b2f4ec2008-11-03 22:13:47 +0100650- vxWorks boot parameters:
651
652 bootvx constructs a valid bootline using the following
Bin Meng9e98b7e2015-10-07 20:19:17 -0700653 environments variables: bootdev, bootfile, ipaddr, netmask,
654 serverip, gatewayip, hostname, othbootargs.
Niklaus Giger0b2f4ec2008-11-03 22:13:47 +0100655 It loads the vxWorks image pointed bootfile.
656
Niklaus Giger0b2f4ec2008-11-03 22:13:47 +0100657 Note: If a "bootargs" environment is defined, it will overwride
658 the defaults discussed just above.
659
Aneesh V2c451f72011-06-16 23:30:47 +0000660- Cache Configuration:
661 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot
662 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot
663 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot
664
Aneesh V93bc2192011-06-16 23:30:51 +0000665- Cache Configuration for ARM:
666 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache
667 controller
668 CONFIG_SYS_PL310_BASE - Physical base address of PL310
669 controller register space
670
wdenk6705d812004-08-02 23:22:59 +0000671- Serial Ports:
Andreas Engel48d01922008-09-08 14:30:53 +0200672 CONFIG_PL010_SERIAL
wdenk6705d812004-08-02 23:22:59 +0000673
674 Define this if you want support for Amba PrimeCell PL010 UARTs.
675
Andreas Engel48d01922008-09-08 14:30:53 +0200676 CONFIG_PL011_SERIAL
wdenk6705d812004-08-02 23:22:59 +0000677
678 Define this if you want support for Amba PrimeCell PL011 UARTs.
679
680 CONFIG_PL011_CLOCK
681
682 If you have Amba PrimeCell PL011 UARTs, set this variable to
683 the clock speed of the UARTs.
684
685 CONFIG_PL01x_PORTS
686
687 If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
688 define this to a list of base addresses for each (supported)
689 port. See e.g. include/configs/versatile.h
690
Karicheri, Muralidharand57dee52014-04-09 15:38:46 -0400691 CONFIG_SERIAL_HW_FLOW_CONTROL
692
693 Define this variable to enable hw flow control in serial driver.
694 Current user of this option is drivers/serial/nsl16550.c driver
wdenk6705d812004-08-02 23:22:59 +0000695
wdenkc6097192002-11-03 00:24:07 +0000696- Console Baudrate:
697 CONFIG_BAUDRATE - in bps
698 Select one of the baudrates listed in
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +0200699 CONFIG_SYS_BAUDRATE_TABLE, see below.
wdenkc6097192002-11-03 00:24:07 +0000700
wdenkc6097192002-11-03 00:24:07 +0000701- Autoboot Command:
702 CONFIG_BOOTCOMMAND
703 Only needed when CONFIG_BOOTDELAY is enabled;
704 define a command string that is automatically executed
705 when no character is read on the console interface
706 within "Boot Delay" after reset.
707
wdenkc6097192002-11-03 00:24:07 +0000708 CONFIG_RAMBOOT and CONFIG_NFSBOOT
wdenk43d96162003-03-06 00:02:04 +0000709 The value of these goes into the environment as
710 "ramboot" and "nfsboot" respectively, and can be used
711 as a convenience, when switching between booting from
Marcel Ziswiler11ccc332008-07-09 08:17:15 +0200712 RAM and NFS.
wdenkc6097192002-11-03 00:24:07 +0000713
714- Pre-Boot Commands:
715 CONFIG_PREBOOT
716
717 When this option is #defined, the existence of the
718 environment variable "preboot" will be checked
719 immediately before starting the CONFIG_BOOTDELAY
720 countdown and/or running the auto-boot command resp.
721 entering interactive mode.
722
723 This feature is especially useful when "preboot" is
724 automatically generated or modified. For an example
725 see the LWMON board specific code: here "preboot" is
726 modified when the user holds down a certain
727 combination of keys on the (special) keyboard when
728 booting the systems
729
730- Serial Download Echo Mode:
731 CONFIG_LOADS_ECHO
732 If defined to 1, all characters received during a
733 serial download (using the "loads" command) are
734 echoed back. This might be needed by some terminal
735 emulations (like "cu"), but may as well just take
736 time on others. This setting #define's the initial
737 value of the "loads_echo" environment variable.
738
Jon Loeliger602ad3b2007-06-11 19:03:39 -0500739- Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined)
wdenkc6097192002-11-03 00:24:07 +0000740 CONFIG_KGDB_BAUDRATE
741 Select one of the baudrates listed in
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +0200742 CONFIG_SYS_BAUDRATE_TABLE, see below.
wdenkc6097192002-11-03 00:24:07 +0000743
Simon Glass302a6482016-03-13 19:07:28 -0600744- Removal of commands
745 If no commands are needed to boot, you can disable
746 CONFIG_CMDLINE to remove them. In this case, the command line
747 will not be available, and when U-Boot wants to execute the
748 boot command (on start-up) it will call board_run_command()
749 instead. This can reduce image size significantly for very
750 simple boot procedures.
751
Wolfgang Denka5ecbe62013-03-23 23:50:31 +0000752- Regular expression support:
753 CONFIG_REGEX
Wolfgang Denk93e14592013-10-04 17:43:24 +0200754 If this variable is defined, U-Boot is linked against
755 the SLRE (Super Light Regular Expression) library,
756 which adds regex support to some commands, as for
757 example "env grep" and "setexpr".
Wolfgang Denka5ecbe62013-03-23 23:50:31 +0000758
Simon Glass45ba8072011-10-15 05:48:20 +0000759- Device tree:
760 CONFIG_OF_CONTROL
761 If this variable is defined, U-Boot will use a device tree
762 to configure its devices, instead of relying on statically
763 compiled #defines in the board file. This option is
764 experimental and only available on a few boards. The device
765 tree is available in the global data as gd->fdt_blob.
766
Simon Glass2c0f79e2011-10-24 19:15:31 +0000767 U-Boot needs to get its device tree from somewhere. This can
Alex Deymo82f766d2017-04-02 01:25:20 -0700768 be done using one of the three options below:
Simon Glassbbb0b122011-10-15 05:48:21 +0000769
770 CONFIG_OF_EMBED
771 If this variable is defined, U-Boot will embed a device tree
772 binary in its image. This device tree file should be in the
773 board directory and called <soc>-<board>.dts. The binary file
774 is then picked up in board_init_f() and made available through
Nobuhiro Iwamatsueb3eb602017-08-26 07:34:14 +0900775 the global data structure as gd->fdt_blob.
Simon Glass45ba8072011-10-15 05:48:20 +0000776
Simon Glass2c0f79e2011-10-24 19:15:31 +0000777 CONFIG_OF_SEPARATE
778 If this variable is defined, U-Boot will build a device tree
779 binary. It will be called u-boot.dtb. Architecture-specific
780 code will locate it at run-time. Generally this works by:
781
782 cat u-boot.bin u-boot.dtb >image.bin
783
784 and in fact, U-Boot does this for you, creating a file called
785 u-boot-dtb.bin which is useful in the common case. You can
786 still use the individual files if you need something more
787 exotic.
788
Alex Deymo82f766d2017-04-02 01:25:20 -0700789 CONFIG_OF_BOARD
790 If this variable is defined, U-Boot will use the device tree
791 provided by the board at runtime instead of embedding one with
792 the image. Only boards defining board_fdt_blob_setup() support
793 this option (see include/fdtdec.h file).
794
wdenkc6097192002-11-03 00:24:07 +0000795- Watchdog:
796 CONFIG_WATCHDOG
797 If this variable is defined, it enables watchdog
Detlev Zundel6abe6fb2011-04-27 05:25:59 +0000798 support for the SoC. There must be support in the SoC
Christophe Leroy907208c2017-07-06 10:23:22 +0200799 specific code for a watchdog. For the 8xx
800 CPUs, the SIU Watchdog feature is enabled in the SYPCR
801 register. When supported for a specific SoC is
802 available, then no further board specific code should
803 be needed to use it.
Detlev Zundel6abe6fb2011-04-27 05:25:59 +0000804
805 CONFIG_HW_WATCHDOG
806 When using a watchdog circuitry external to the used
807 SoC, then define this variable and provide board
808 specific code for the "hw_watchdog_reset" function.
wdenkc6097192002-11-03 00:24:07 +0000809
Heiko Schocher7bae0d62015-01-21 08:38:22 +0100810 CONFIG_AT91_HW_WDT_TIMEOUT
811 specify the timeout in seconds. default 2 seconds.
812
wdenkc6097192002-11-03 00:24:07 +0000813- Real-Time Clock:
814
Jon Loeliger602ad3b2007-06-11 19:03:39 -0500815 When CONFIG_CMD_DATE is selected, the type of the RTC
wdenkc6097192002-11-03 00:24:07 +0000816 has to be selected, too. Define exactly one of the
817 following options:
818
wdenkc6097192002-11-03 00:24:07 +0000819 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
Fabio Estevam4e8b7542011-10-24 06:44:15 +0000820 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC
wdenkc6097192002-11-03 00:24:07 +0000821 CONFIG_RTC_MC146818 - use MC146818 RTC
wdenk1cb8e982003-03-06 21:55:29 +0000822 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
wdenkc6097192002-11-03 00:24:07 +0000823 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
wdenk7f70e852003-05-20 14:25:27 +0000824 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
Markus Niebel412921d2014-07-21 11:06:16 +0200825 CONFIG_RTC_DS1339 - use Maxim, Inc. DS1339 RTC
wdenk3bac3512003-03-12 10:41:04 +0000826 CONFIG_RTC_DS164x - use Dallas DS164x RTC
Tor Krill9536dfc2008-03-15 15:40:26 +0100827 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC
wdenk4c0d4c32004-06-09 17:34:58 +0000828 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
Chris Packham2bd3cab2017-05-30 12:03:33 +1200829 CONFIG_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337
Heiko Schocher71d19f32011-03-28 09:24:22 +0200830 CONFIG_SYS_RV3029_TCR - enable trickle charger on
831 RV3029 RTC.
wdenkc6097192002-11-03 00:24:07 +0000832
wdenkb37c7e52003-06-30 16:24:52 +0000833 Note that if the RTC uses I2C, then the I2C interface
834 must also be configured. See I2C Support, below.
835
Peter Tysere92739d2008-12-17 16:36:21 -0600836- GPIO Support:
837 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO
Peter Tysere92739d2008-12-17 16:36:21 -0600838
Chris Packham5dec49c2010-12-19 10:12:13 +0000839 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of
840 chip-ngpio pairs that tell the PCA953X driver the number of
841 pins supported by a particular chip.
842
Peter Tysere92739d2008-12-17 16:36:21 -0600843 Note that if the GPIO device uses I2C, then the I2C interface
844 must also be configured. See I2C Support, below.
845
Simon Glassaa532332014-06-11 23:29:41 -0600846- I/O tracing:
847 When CONFIG_IO_TRACE is selected, U-Boot intercepts all I/O
848 accesses and can checksum them or write a list of them out
849 to memory. See the 'iotrace' command for details. This is
850 useful for testing device drivers since it can confirm that
851 the driver behaves the same way before and after a code
852 change. Currently this is supported on sandbox and arm. To
853 add support for your architecture, add '#include <iotrace.h>'
854 to the bottom of arch/<arch>/include/asm/io.h and test.
855
856 Example output from the 'iotrace stats' command is below.
857 Note that if the trace buffer is exhausted, the checksum will
858 still continue to operate.
859
860 iotrace is enabled
861 Start: 10000000 (buffer start address)
862 Size: 00010000 (buffer size)
863 Offset: 00000120 (current buffer offset)
864 Output: 10000120 (start + offset)
865 Count: 00000018 (number of trace records)
866 CRC32: 9526fb66 (CRC32 of all trace records)
867
wdenkc6097192002-11-03 00:24:07 +0000868- Timestamp Support:
869
wdenk43d96162003-03-06 00:02:04 +0000870 When CONFIG_TIMESTAMP is selected, the timestamp
871 (date and time) of an image is printed by image
872 commands like bootm or iminfo. This option is
Jon Loeliger602ad3b2007-06-11 19:03:39 -0500873 automatically enabled when you select CONFIG_CMD_DATE .
wdenkc6097192002-11-03 00:24:07 +0000874
Karl O. Pinc923c46f2012-08-16 06:20:15 +0000875- Partition Labels (disklabels) Supported:
876 Zero or more of the following:
877 CONFIG_MAC_PARTITION Apple's MacOS partition table.
Karl O. Pinc923c46f2012-08-16 06:20:15 +0000878 CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc.
879 CONFIG_EFI_PARTITION GPT partition table, common when EFI is the
880 bootloader. Note 2TB partition limit; see
881 disk/part_efi.c
882 CONFIG_MTD_PARTITIONS Memory Technology Device partition table.
wdenkc6097192002-11-03 00:24:07 +0000883
Simon Glassfc843a02017-05-17 03:25:30 -0600884 If IDE or SCSI support is enabled (CONFIG_IDE or
Simon Glassc649e3c2016-05-01 11:36:02 -0600885 CONFIG_SCSI) you must configure support for at
Karl O. Pinc923c46f2012-08-16 06:20:15 +0000886 least one non-MTD partition type as well.
wdenkc6097192002-11-03 00:24:07 +0000887
888- IDE Reset method:
wdenk4d13cba2004-03-14 14:09:05 +0000889 CONFIG_IDE_RESET_ROUTINE - this is defined in several
890 board configurations files but used nowhere!
wdenkc6097192002-11-03 00:24:07 +0000891
wdenk4d13cba2004-03-14 14:09:05 +0000892 CONFIG_IDE_RESET - is this is defined, IDE Reset will
893 be performed by calling the function
894 ide_set_reset(int reset)
895 which has to be defined in a board specific file
wdenkc6097192002-11-03 00:24:07 +0000896
897- ATAPI Support:
898 CONFIG_ATAPI
899
900 Set this to enable ATAPI support.
901
wdenkc40b2952004-03-13 23:29:43 +0000902- LBA48 Support
903 CONFIG_LBA48
904
905 Set this to enable support for disks larger than 137GB
Heiko Schocher4b142fe2009-12-03 11:21:21 +0100906 Also look at CONFIG_SYS_64BIT_LBA.
wdenkc40b2952004-03-13 23:29:43 +0000907 Whithout these , LBA48 support uses 32bit variables and will 'only'
908 support disks up to 2.1TB.
909
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +0200910 CONFIG_SYS_64BIT_LBA:
wdenkc40b2952004-03-13 23:29:43 +0000911 When enabled, makes the IDE subsystem use 64bit sector addresses.
912 Default is 32bit.
913
wdenkc6097192002-11-03 00:24:07 +0000914- SCSI Support:
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +0200915 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and
916 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID *
917 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the
wdenkc6097192002-11-03 00:24:07 +0000918 maximum numbers of LUNs, SCSI ID's and target
919 devices.
wdenkc6097192002-11-03 00:24:07 +0000920
Wolfgang Denk93e14592013-10-04 17:43:24 +0200921 The environment variable 'scsidevs' is set to the number of
922 SCSI devices found during the last scan.
Stefan Reinauer447c0312012-10-29 05:23:48 +0000923
wdenkc6097192002-11-03 00:24:07 +0000924- NETWORK Support (PCI):
wdenk682011f2003-06-03 23:54:09 +0000925 CONFIG_E1000
Kyle Moffettce5207e2011-10-18 11:05:29 +0000926 Support for Intel 8254x/8257x gigabit chips.
927
928 CONFIG_E1000_SPI
929 Utility code for direct access to the SPI bus on Intel 8257x.
930 This does not do anything useful unless you set at least one
931 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC.
932
933 CONFIG_E1000_SPI_GENERIC
934 Allow generic access to the SPI bus on the Intel 8257x, for
935 example with the "sspi" command.
936
wdenkc6097192002-11-03 00:24:07 +0000937 CONFIG_EEPRO100
938 Support for Intel 82557/82559/82559ER chips.
Marcel Ziswiler11ccc332008-07-09 08:17:15 +0200939 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM
wdenkc6097192002-11-03 00:24:07 +0000940 write routine for first time initialisation.
941
942 CONFIG_TULIP
943 Support for Digital 2114x chips.
944 Optional CONFIG_TULIP_SELECT_MEDIA for board specific
945 modem chip initialisation (KS8761/QS6611).
946
947 CONFIG_NATSEMI
948 Support for National dp83815 chips.
949
950 CONFIG_NS8382X
951 Support for National dp8382[01] gigabit chips.
952
wdenk45219c42003-05-12 21:50:16 +0000953- NETWORK Support (other):
954
Jens Scharsigc041e9d2010-01-23 12:03:45 +0100955 CONFIG_DRIVER_AT91EMAC
956 Support for AT91RM9200 EMAC.
957
958 CONFIG_RMII
959 Define this to use reduced MII inteface
960
961 CONFIG_DRIVER_AT91EMAC_QUIET
962 If this defined, the driver is quiet.
963 The driver doen't show link status messages.
964
Rob Herringefdd7312011-12-15 11:15:49 +0000965 CONFIG_CALXEDA_XGMAC
966 Support for the Calxeda XGMAC device
967
Ashok3bb46d22012-10-15 06:20:47 +0000968 CONFIG_LAN91C96
wdenk45219c42003-05-12 21:50:16 +0000969 Support for SMSC's LAN91C96 chips.
970
wdenk45219c42003-05-12 21:50:16 +0000971 CONFIG_LAN91C96_USE_32_BIT
972 Define this to enable 32 bit addressing
973
Ashok3bb46d22012-10-15 06:20:47 +0000974 CONFIG_SMC91111
wdenkf39748a2004-06-09 13:37:52 +0000975 Support for SMSC's LAN91C111 chip
976
977 CONFIG_SMC91111_BASE
978 Define this to hold the physical address
979 of the device (I/O space)
980
981 CONFIG_SMC_USE_32_BIT
982 Define this if data bus is 32 bits
983
984 CONFIG_SMC_USE_IOFUNCS
985 Define this to use i/o functions instead of macros
986 (some hardware wont work with macros)
987
Heiko Schocherdc02bad2011-11-15 10:00:04 -0500988 CONFIG_DRIVER_TI_EMAC
989 Support for davinci emac
990
991 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT
992 Define this if you have more then 3 PHYs.
993
Macpaul Linb3dbf4a52010-12-21 16:59:46 +0800994 CONFIG_FTGMAC100
995 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet
996
997 CONFIG_FTGMAC100_EGIGA
998 Define this to use GE link update with gigabit PHY.
999 Define this if FTGMAC100 is connected to gigabit PHY.
1000 If your system has 10/100 PHY only, it might not occur
1001 wrong behavior. Because PHY usually return timeout or
1002 useless data when polling gigabit status and gigabit
1003 control registers. This behavior won't affect the
1004 correctnessof 10/100 link speed update.
1005
Yoshihiro Shimoda3d0075f2011-01-27 10:06:03 +09001006 CONFIG_SH_ETHER
1007 Support for Renesas on-chip Ethernet controller
1008
1009 CONFIG_SH_ETHER_USE_PORT
1010 Define the number of ports to be used
1011
1012 CONFIG_SH_ETHER_PHY_ADDR
1013 Define the ETH PHY's address
1014
Yoshihiro Shimoda68260aa2011-01-27 10:06:08 +09001015 CONFIG_SH_ETHER_CACHE_WRITEBACK
1016 If this option is set, the driver enables cache flush.
1017
Heiko Schocherb2f97cf2014-07-18 06:07:19 +02001018- PWM Support:
1019 CONFIG_PWM_IMX
Robert P. J. Day5052e812016-09-13 08:35:18 -04001020 Support for PWM module on the imx6.
Heiko Schocherb2f97cf2014-07-18 06:07:19 +02001021
Vadim Bendebury5e124722011-10-17 08:36:14 +00001022- TPM Support:
Che-liang Chiou90899cc2013-04-12 11:04:34 +00001023 CONFIG_TPM
1024 Support TPM devices.
1025
Christophe Ricard0766ad22015-10-06 22:54:41 +02001026 CONFIG_TPM_TIS_INFINEON
1027 Support for Infineon i2c bus TPM devices. Only one device
Tom Wai-Hong Tam1b393db2013-04-12 11:04:37 +00001028 per system is supported at this time.
1029
Tom Wai-Hong Tam1b393db2013-04-12 11:04:37 +00001030 CONFIG_TPM_TIS_I2C_BURST_LIMITATION
1031 Define the burst count bytes upper limit
1032
Christophe Ricard3aa74082016-01-21 23:27:13 +01001033 CONFIG_TPM_ST33ZP24
1034 Support for STMicroelectronics TPM devices. Requires DM_TPM support.
1035
1036 CONFIG_TPM_ST33ZP24_I2C
1037 Support for STMicroelectronics ST33ZP24 I2C devices.
1038 Requires TPM_ST33ZP24 and I2C.
1039
Christophe Ricardb75fdc12016-01-21 23:27:14 +01001040 CONFIG_TPM_ST33ZP24_SPI
1041 Support for STMicroelectronics ST33ZP24 SPI devices.
1042 Requires TPM_ST33ZP24 and SPI.
1043
Dirk Eibachc01939c2013-06-26 15:55:15 +02001044 CONFIG_TPM_ATMEL_TWI
1045 Support for Atmel TWI TPM device. Requires I2C support.
1046
Che-liang Chiou90899cc2013-04-12 11:04:34 +00001047 CONFIG_TPM_TIS_LPC
Vadim Bendebury5e124722011-10-17 08:36:14 +00001048 Support for generic parallel port TPM devices. Only one device
1049 per system is supported at this time.
1050
1051 CONFIG_TPM_TIS_BASE_ADDRESS
1052 Base address where the generic TPM device is mapped
1053 to. Contemporary x86 systems usually map it at
1054 0xfed40000.
1055
Reinhard Pfaube6c1522013-06-26 15:55:13 +02001056 CONFIG_TPM
1057 Define this to enable the TPM support library which provides
1058 functional interfaces to some TPM commands.
1059 Requires support for a TPM device.
1060
1061 CONFIG_TPM_AUTH_SESSIONS
1062 Define this to enable authorized functions in the TPM library.
1063 Requires CONFIG_TPM and CONFIG_SHA1.
1064
wdenkc6097192002-11-03 00:24:07 +00001065- USB Support:
1066 At the moment only the UHCI host controller is
Heiko Schocher064b55c2017-06-14 05:49:40 +02001067 supported (PIP405, MIP405); define
wdenkc6097192002-11-03 00:24:07 +00001068 CONFIG_USB_UHCI to enable it.
1069 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
wdenk30d56fa2004-10-09 22:44:59 +00001070 and define CONFIG_USB_STORAGE to enable the USB
wdenkc6097192002-11-03 00:24:07 +00001071 storage devices.
1072 Note:
1073 Supported are USB Keyboards and USB Floppy drives
1074 (TEAC FD-05PUB).
wdenk4d13cba2004-03-14 14:09:05 +00001075
Simon Glass9ab4ce22012-02-27 10:52:47 +00001076 CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the
1077 txfilltuning field in the EHCI controller on reset.
1078
Oleksandr Tymoshenko6e9e0622014-02-01 21:51:25 -07001079 CONFIG_USB_DWC2_REG_ADDR the physical CPU address of the DWC2
1080 HW module registers.
1081
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +02001082- USB Device:
1083 Define the below if you wish to use the USB console.
1084 Once firmware is rebuilt from a serial console issue the
1085 command "setenv stdin usbtty; setenv stdout usbtty" and
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001086 attach your USB cable. The Unix command "dmesg" should print
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +02001087 it has found a new device. The environment variable usbtty
1088 can be set to gserial or cdc_acm to enable your device to
Wolfgang Denk386eda02006-06-14 18:14:56 +02001089 appear to a USB host as a Linux gserial device or a
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +02001090 Common Device Class Abstract Control Model serial device.
1091 If you select usbtty = gserial you should be able to enumerate
1092 a Linux host by
1093 # modprobe usbserial vendor=0xVendorID product=0xProductID
1094 else if using cdc_acm, simply setting the environment
1095 variable usbtty to be cdc_acm should suffice. The following
1096 might be defined in YourBoardName.h
Wolfgang Denk386eda02006-06-14 18:14:56 +02001097
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +02001098 CONFIG_USB_DEVICE
1099 Define this to build a UDC device
wdenkc6097192002-11-03 00:24:07 +00001100
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +02001101 CONFIG_USB_TTY
1102 Define this to have a tty type of device available to
1103 talk to the UDC device
Wolfgang Denk386eda02006-06-14 18:14:56 +02001104
Vipin KUMARf9da0f82012-03-26 15:38:06 +05301105 CONFIG_USBD_HS
1106 Define this to enable the high speed support for usb
1107 device and usbtty. If this feature is enabled, a routine
1108 int is_usbd_high_speed(void)
1109 also needs to be defined by the driver to dynamically poll
1110 whether the enumeration has succeded at high speed or full
1111 speed.
1112
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001113 CONFIG_SYS_CONSOLE_IS_IN_ENV
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +02001114 Define this if you want stdin, stdout &/or stderr to
1115 be set to usbtty.
1116
Wolfgang Denk386eda02006-06-14 18:14:56 +02001117 If you have a USB-IF assigned VendorID then you may wish to
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +02001118 define your own vendor specific values either in BoardName.h
Wolfgang Denk386eda02006-06-14 18:14:56 +02001119 or directly in usbd_vendor_info.h. If you don't define
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +02001120 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME,
1121 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot
1122 should pretend to be a Linux device to it's target host.
1123
1124 CONFIG_USBD_MANUFACTURER
1125 Define this string as the name of your company for
1126 - CONFIG_USBD_MANUFACTURER "my company"
Wolfgang Denk386eda02006-06-14 18:14:56 +02001127
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +02001128 CONFIG_USBD_PRODUCT_NAME
1129 Define this string as the name of your product
1130 - CONFIG_USBD_PRODUCT_NAME "acme usb device"
1131
1132 CONFIG_USBD_VENDORID
1133 Define this as your assigned Vendor ID from the USB
1134 Implementors Forum. This *must* be a genuine Vendor ID
1135 to avoid polluting the USB namespace.
1136 - CONFIG_USBD_VENDORID 0xFFFF
Wolfgang Denk386eda02006-06-14 18:14:56 +02001137
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +02001138 CONFIG_USBD_PRODUCTID
1139 Define this as the unique Product ID
1140 for your device
1141 - CONFIG_USBD_PRODUCTID 0xFFFF
wdenkc6097192002-11-03 00:24:07 +00001142
Igor Grinbergd70a5602011-12-12 12:08:35 +02001143- ULPI Layer Support:
1144 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via
1145 the generic ULPI layer. The generic layer accesses the ULPI PHY
1146 via the platform viewport, so you need both the genric layer and
1147 the viewport enabled. Currently only Chipidea/ARC based
1148 viewport is supported.
1149 To enable the ULPI layer support, define CONFIG_USB_ULPI and
1150 CONFIG_USB_ULPI_VIEWPORT in your board configuration file.
Lucas Stach6d365ea2012-10-01 00:44:35 +02001151 If your ULPI phy needs a different reference clock than the
1152 standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to
1153 the appropriate value in Hz.
wdenkc6097192002-11-03 00:24:07 +00001154
1155- MMC Support:
1156 The MMC controller on the Intel PXA is supported. To
1157 enable this define CONFIG_MMC. The MMC can be
1158 accessed from the boot prompt by mapping the device
1159 to physical memory similar to flash. Command line is
Jon Loeliger602ad3b2007-06-11 19:03:39 -05001160 enabled with CONFIG_CMD_MMC. The MMC driver also works with
1161 the FAT fs. This is enabled with CONFIG_CMD_FAT.
wdenkc6097192002-11-03 00:24:07 +00001162
Yoshihiro Shimodaafb35662011-07-04 22:21:22 +00001163 CONFIG_SH_MMCIF
1164 Support for Renesas on-chip MMCIF controller
1165
1166 CONFIG_SH_MMCIF_ADDR
1167 Define the base address of MMCIF registers
1168
1169 CONFIG_SH_MMCIF_CLK
1170 Define the clock frequency for MMCIF
1171
Pierre Aubert1fd93c62014-04-24 10:30:08 +02001172 CONFIG_SUPPORT_EMMC_BOOT
1173 Enable some additional features of the eMMC boot partitions.
1174
Tom Rinib3ba6e92013-03-14 05:32:47 +00001175- USB Device Firmware Update (DFU) class support:
Marek Vasutbb4059a2018-02-16 16:41:18 +01001176 CONFIG_DFU_OVER_USB
Tom Rinib3ba6e92013-03-14 05:32:47 +00001177 This enables the USB portion of the DFU USB class
1178
Tom Rinib3ba6e92013-03-14 05:32:47 +00001179 CONFIG_DFU_MMC
1180 This enables support for exposing (e)MMC devices via DFU.
1181
Pantelis Antoniouc6631762013-03-14 05:32:52 +00001182 CONFIG_DFU_NAND
1183 This enables support for exposing NAND devices via DFU.
1184
Afzal Mohammeda9479f02013-09-18 01:15:24 +05301185 CONFIG_DFU_RAM
1186 This enables support for exposing RAM via DFU.
1187 Note: DFU spec refer to non-volatile memory usage, but
1188 allow usages beyond the scope of spec - here RAM usage,
1189 one that would help mostly the developer.
1190
Heiko Schochere7e75c72013-06-12 06:05:51 +02001191 CONFIG_SYS_DFU_DATA_BUF_SIZE
1192 Dfu transfer uses a buffer before writing data to the
1193 raw storage device. Make the size (in bytes) of this buffer
1194 configurable. The size of this buffer is also configurable
1195 through the "dfu_bufsiz" environment variable.
1196
Pantelis Antoniouea2453d2013-03-14 05:32:48 +00001197 CONFIG_SYS_DFU_MAX_FILE_SIZE
1198 When updating files rather than the raw storage device,
1199 we use a static buffer to copy the file into and then write
1200 the buffer once we've been given the whole file. Define
1201 this to the maximum filesize (in bytes) for the buffer.
1202 Default is 4 MiB if undefined.
1203
Heiko Schocher001a8312014-03-18 08:09:56 +01001204 DFU_DEFAULT_POLL_TIMEOUT
1205 Poll timeout [ms], is the timeout a device can send to the
1206 host. The host must wait for this timeout before sending
1207 a subsequent DFU_GET_STATUS request to the device.
1208
1209 DFU_MANIFEST_POLL_TIMEOUT
1210 Poll timeout [ms], which the device sends to the host when
1211 entering dfuMANIFEST state. Host waits this timeout, before
1212 sending again an USB request to the device.
1213
wdenk6705d812004-08-02 23:22:59 +00001214- Journaling Flash filesystem support:
Simon Glassb2482df2016-10-02 18:00:59 -06001215 CONFIG_JFFS2_NAND
wdenk6705d812004-08-02 23:22:59 +00001216 Define these for a default partition on a NAND device
1217
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001218 CONFIG_SYS_JFFS2_FIRST_SECTOR,
1219 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS
wdenk6705d812004-08-02 23:22:59 +00001220 Define these for a default partition on a NOR device
1221
wdenkc6097192002-11-03 00:24:07 +00001222- Keyboard Support:
Simon Glass39f615e2015-11-11 10:05:47 -07001223 See Kconfig help for available keyboard drivers.
1224
1225 CONFIG_KEYBOARD
1226
1227 Define this to enable a custom keyboard support.
1228 This simply calls drv_keyboard_init() which must be
1229 defined in your board-specific files. This option is deprecated
1230 and is only used by novena. For new boards, use driver model
1231 instead.
wdenkc6097192002-11-03 00:24:07 +00001232
1233- Video support:
Timur Tabi7d3053f2011-02-15 17:09:19 -06001234 CONFIG_FSL_DIU_FB
Wolfgang Denk04e5ae72011-09-11 21:24:09 +02001235 Enable the Freescale DIU video driver. Reference boards for
Timur Tabi7d3053f2011-02-15 17:09:19 -06001236 SOCs that have a DIU should define this macro to enable DIU
1237 support, and should also define these other macros:
1238
1239 CONFIG_SYS_DIU_ADDR
1240 CONFIG_VIDEO
Timur Tabi7d3053f2011-02-15 17:09:19 -06001241 CONFIG_CFB_CONSOLE
1242 CONFIG_VIDEO_SW_CURSOR
1243 CONFIG_VGA_AS_SINGLE_DEVICE
1244 CONFIG_VIDEO_LOGO
1245 CONFIG_VIDEO_BMP_LOGO
1246
Timur Tabiba8e76b2011-04-11 14:18:22 -05001247 The DIU driver will look for the 'video-mode' environment
1248 variable, and if defined, enable the DIU as a console during
Fabio Estevam8eca9432016-04-02 11:53:18 -03001249 boot. See the documentation file doc/README.video for a
Timur Tabiba8e76b2011-04-11 14:18:22 -05001250 description of this variable.
Timur Tabi7d3053f2011-02-15 17:09:19 -06001251
wdenkc6097192002-11-03 00:24:07 +00001252- LCD Support: CONFIG_LCD
1253
1254 Define this to enable LCD support (for output to LCD
1255 display); also select one of the supported displays
1256 by defining one of these:
1257
Stelian Pop39cf4802008-05-09 21:57:18 +02001258 CONFIG_ATMEL_LCD:
1259
1260 HITACHI TX09D70VM1CCA, 3.5", 240x320.
1261
wdenkfd3103b2003-11-25 16:55:19 +00001262 CONFIG_NEC_NL6448AC33:
wdenkc6097192002-11-03 00:24:07 +00001263
wdenkfd3103b2003-11-25 16:55:19 +00001264 NEC NL6448AC33-18. Active, color, single scan.
wdenkc6097192002-11-03 00:24:07 +00001265
wdenkfd3103b2003-11-25 16:55:19 +00001266 CONFIG_NEC_NL6448BC20
wdenkc6097192002-11-03 00:24:07 +00001267
wdenkfd3103b2003-11-25 16:55:19 +00001268 NEC NL6448BC20-08. 6.5", 640x480.
1269 Active, color, single scan.
1270
1271 CONFIG_NEC_NL6448BC33_54
1272
1273 NEC NL6448BC33-54. 10.4", 640x480.
wdenkc6097192002-11-03 00:24:07 +00001274 Active, color, single scan.
1275
1276 CONFIG_SHARP_16x9
1277
1278 Sharp 320x240. Active, color, single scan.
1279 It isn't 16x9, and I am not sure what it is.
1280
1281 CONFIG_SHARP_LQ64D341
1282
1283 Sharp LQ64D341 display, 640x480.
1284 Active, color, single scan.
1285
1286 CONFIG_HLD1045
1287
1288 HLD1045 display, 640x480.
1289 Active, color, single scan.
1290
1291 CONFIG_OPTREX_BW
1292
1293 Optrex CBL50840-2 NF-FW 99 22 M5
1294 or
1295 Hitachi LMG6912RPFC-00T
1296 or
1297 Hitachi SP14Q002
1298
1299 320x240. Black & white.
1300
Simon Glass676d3192012-10-17 13:24:54 +00001301 CONFIG_LCD_ALIGNMENT
1302
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08001303 Normally the LCD is page-aligned (typically 4KB). If this is
Simon Glass676d3192012-10-17 13:24:54 +00001304 defined then the LCD will be aligned to this value instead.
1305 For ARM it is sometimes useful to use MMU_SECTION_SIZE
1306 here, since it is cheaper to change data cache settings on
1307 a per-section basis.
1308
1309
Hannes Petermaier604c7d42015-03-27 08:01:38 +01001310 CONFIG_LCD_ROTATION
1311
1312 Sometimes, for example if the display is mounted in portrait
1313 mode or even if it's mounted landscape but rotated by 180degree,
1314 we need to rotate our content of the display relative to the
1315 framebuffer, so that user can read the messages which are
1316 printed out.
1317 Once CONFIG_LCD_ROTATION is defined, the lcd_console will be
1318 initialized with a given rotation from "vl_rot" out of
1319 "vidinfo_t" which is provided by the board specific code.
1320 The value for vl_rot is coded as following (matching to
1321 fbcon=rotate:<n> linux-kernel commandline):
1322 0 = no rotation respectively 0 degree
1323 1 = 90 degree rotation
1324 2 = 180 degree rotation
1325 3 = 270 degree rotation
1326
1327 If CONFIG_LCD_ROTATION is not defined, the console will be
1328 initialized with 0degree rotation.
1329
Tom Wai-Hong Tam45d7f522012-09-28 15:11:16 +00001330 CONFIG_LCD_BMP_RLE8
1331
1332 Support drawing of RLE8-compressed bitmaps on the LCD.
1333
Tom Wai-Hong Tam735987c2012-12-05 14:46:40 +00001334 CONFIG_I2C_EDID
1335
1336 Enables an 'i2c edid' command which can read EDID
1337 information over I2C from an attached LCD display.
1338
wdenk7152b1d2003-09-05 23:19:14 +00001339- Splash Screen Support: CONFIG_SPLASH_SCREEN
wdenkd791b1d2003-04-20 14:04:18 +00001340
wdenk8bde7f72003-06-27 21:31:46 +00001341 If this option is set, the environment is checked for
1342 a variable "splashimage". If found, the usual display
1343 of logo, copyright and system information on the LCD
wdenke94d2cd2004-06-30 22:59:18 +00001344 is suppressed and the BMP image at the address
wdenk8bde7f72003-06-27 21:31:46 +00001345 specified in "splashimage" is loaded instead. The
1346 console is redirected to the "nulldev", too. This
1347 allows for a "silent" boot where a splash screen is
1348 loaded very quickly after power-on.
wdenkd791b1d2003-04-20 14:04:18 +00001349
Nikita Kiryanovc0880482013-02-24 21:28:43 +00001350 CONFIG_SPLASHIMAGE_GUARD
1351
1352 If this option is set, then U-Boot will prevent the environment
1353 variable "splashimage" from being set to a problematic address
Fabio Estevamab5645f2016-03-23 12:46:12 -03001354 (see doc/README.displaying-bmps).
Nikita Kiryanovc0880482013-02-24 21:28:43 +00001355 This option is useful for targets where, due to alignment
1356 restrictions, an improperly aligned BMP image will cause a data
1357 abort. If you think you will not have problems with unaligned
1358 accesses (for example because your toolchain prevents them)
1359 there is no need to set this option.
1360
Matthias Weisser1ca298c2009-07-09 16:07:30 +02001361 CONFIG_SPLASH_SCREEN_ALIGN
1362
1363 If this option is set the splash image can be freely positioned
1364 on the screen. Environment variable "splashpos" specifies the
1365 position as "x,y". If a positive number is given it is used as
1366 number of pixel from left/top. If a negative number is given it
1367 is used as number of pixel from right/bottom. You can also
1368 specify 'm' for centering the image.
1369
1370 Example:
1371 setenv splashpos m,m
1372 => image at center of screen
1373
1374 setenv splashpos 30,20
1375 => image at x = 30 and y = 20
1376
1377 setenv splashpos -10,m
1378 => vertically centered image
1379 at x = dspWidth - bmpWidth - 9
1380
Stefan Roese98f4a3d2005-09-22 09:04:17 +02001381- Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
1382
1383 If this option is set, additionally to standard BMP
1384 images, gzipped BMP images can be displayed via the
1385 splashscreen support or the bmp command.
1386
Anatolij Gustschind5011762010-03-15 14:50:25 +01001387- Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8
1388
1389 If this option is set, 8-bit RLE compressed BMP images
1390 can be displayed via the splashscreen support or the
1391 bmp command.
1392
wdenkc29fdfc2003-08-29 20:57:53 +00001393- Compression support:
Kees Cook8ef70472013-08-16 07:59:12 -07001394 CONFIG_GZIP
1395
1396 Enabled by default to support gzip compressed images.
1397
wdenkc29fdfc2003-08-29 20:57:53 +00001398 CONFIG_BZIP2
1399
1400 If this option is set, support for bzip2 compressed
1401 images is included. If not, only uncompressed and gzip
1402 compressed images are supported.
1403
wdenk42d1f032003-10-15 23:53:47 +00001404 NOTE: the bzip2 algorithm requires a lot of RAM, so
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001405 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should
wdenk42d1f032003-10-15 23:53:47 +00001406 be at least 4MB.
wdenkd791b1d2003-04-20 14:04:18 +00001407
wdenk17ea1172004-06-06 21:51:03 +00001408- MII/PHY support:
wdenk17ea1172004-06-06 21:51:03 +00001409 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
1410
1411 The clock frequency of the MII bus
1412
wdenk17ea1172004-06-06 21:51:03 +00001413 CONFIG_PHY_RESET_DELAY
1414
1415 Some PHY like Intel LXT971A need extra delay after
1416 reset before any MII register access is possible.
1417 For such PHY, set this option to the usec delay
1418 required. (minimum 300usec for LXT971A)
1419
1420 CONFIG_PHY_CMD_DELAY (ppc4xx)
1421
1422 Some PHY like Intel LXT971A need extra delay after
1423 command issued before MII status register can be read
1424
wdenkc6097192002-11-03 00:24:07 +00001425- IP address:
1426 CONFIG_IPADDR
1427
1428 Define a default value for the IP address to use for
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001429 the default Ethernet interface, in case this is not
wdenkc6097192002-11-03 00:24:07 +00001430 determined through e.g. bootp.
Wolfgang Denk1ebcd652011-10-26 10:21:22 +00001431 (Environment variable "ipaddr")
wdenkc6097192002-11-03 00:24:07 +00001432
1433- Server IP address:
1434 CONFIG_SERVERIP
1435
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001436 Defines a default value for the IP address of a TFTP
wdenkc6097192002-11-03 00:24:07 +00001437 server to contact when using the "tftboot" command.
Wolfgang Denk1ebcd652011-10-26 10:21:22 +00001438 (Environment variable "serverip")
wdenkc6097192002-11-03 00:24:07 +00001439
Robin Getz97cfe862009-07-21 12:15:28 -04001440 CONFIG_KEEP_SERVERADDR
1441
1442 Keeps the server's MAC address, in the env 'serveraddr'
1443 for passing to bootargs (like Linux's netconsole option)
1444
Wolfgang Denk1ebcd652011-10-26 10:21:22 +00001445- Gateway IP address:
1446 CONFIG_GATEWAYIP
1447
1448 Defines a default value for the IP address of the
1449 default router where packets to other networks are
1450 sent to.
1451 (Environment variable "gatewayip")
1452
1453- Subnet mask:
1454 CONFIG_NETMASK
1455
1456 Defines a default value for the subnet mask (or
1457 routing prefix) which is used to determine if an IP
1458 address belongs to the local subnet or needs to be
1459 forwarded through a router.
1460 (Environment variable "netmask")
1461
David Updegraff53a5c422007-06-11 10:41:07 -05001462- Multicast TFTP Mode:
1463 CONFIG_MCAST_TFTP
1464
1465 Defines whether you want to support multicast TFTP as per
1466 rfc-2090; for example to work with atftp. Lets lots of targets
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001467 tftp down the same boot image concurrently. Note: the Ethernet
David Updegraff53a5c422007-06-11 10:41:07 -05001468 driver in use must provide a function: mcast() to join/leave a
1469 multicast group.
1470
wdenkc6097192002-11-03 00:24:07 +00001471- BOOTP Recovery Mode:
1472 CONFIG_BOOTP_RANDOM_DELAY
1473
1474 If you have many targets in a network that try to
1475 boot using BOOTP, you may want to avoid that all
1476 systems send out BOOTP requests at precisely the same
1477 moment (which would happen for instance at recovery
1478 from a power failure, when all systems will try to
1479 boot, thus flooding the BOOTP server. Defining
1480 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
1481 inserted before sending out BOOTP requests. The
Wolfgang Denk6c33c782007-08-06 23:21:05 +02001482 following delays are inserted then:
wdenkc6097192002-11-03 00:24:07 +00001483
1484 1st BOOTP request: delay 0 ... 1 sec
1485 2nd BOOTP request: delay 0 ... 2 sec
1486 3rd BOOTP request: delay 0 ... 4 sec
1487 4th and following
1488 BOOTP requests: delay 0 ... 8 sec
1489
Thierry Reding92ac8ac2014-08-19 10:21:24 +02001490 CONFIG_BOOTP_ID_CACHE_SIZE
1491
1492 BOOTP packets are uniquely identified using a 32-bit ID. The
1493 server will copy the ID from client requests to responses and
1494 U-Boot will use this to determine if it is the destination of
1495 an incoming response. Some servers will check that addresses
1496 aren't in use before handing them out (usually using an ARP
1497 ping) and therefore take up to a few hundred milliseconds to
1498 respond. Network congestion may also influence the time it
1499 takes for a response to make it back to the client. If that
1500 time is too long, U-Boot will retransmit requests. In order
1501 to allow earlier responses to still be accepted after these
1502 retransmissions, U-Boot's BOOTP client keeps a small cache of
1503 IDs. The CONFIG_BOOTP_ID_CACHE_SIZE controls the size of this
1504 cache. The default is to keep IDs for up to four outstanding
1505 requests. Increasing this will allow U-Boot to accept offers
1506 from a BOOTP client in networks with unusually high latency.
1507
stroesefe389a82003-08-28 14:17:32 +00001508- DHCP Advanced Options:
Jon Loeliger1fe80d72007-07-09 22:08:34 -05001509 You can fine tune the DHCP functionality by defining
1510 CONFIG_BOOTP_* symbols:
stroesefe389a82003-08-28 14:17:32 +00001511
Jon Loeliger1fe80d72007-07-09 22:08:34 -05001512 CONFIG_BOOTP_NISDOMAIN
Jon Loeliger1fe80d72007-07-09 22:08:34 -05001513 CONFIG_BOOTP_BOOTFILESIZE
Jon Loeliger1fe80d72007-07-09 22:08:34 -05001514 CONFIG_BOOTP_SEND_HOSTNAME
1515 CONFIG_BOOTP_NTPSERVER
1516 CONFIG_BOOTP_TIMEOFFSET
1517 CONFIG_BOOTP_VENDOREX
Joe Hershberger2c00e092012-05-23 07:59:19 +00001518 CONFIG_BOOTP_MAY_FAIL
stroesefe389a82003-08-28 14:17:32 +00001519
Wilson Callan5d110f02007-07-28 10:56:13 -04001520 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip
1521 environment variable, not the BOOTP server.
stroesefe389a82003-08-28 14:17:32 +00001522
Joe Hershberger2c00e092012-05-23 07:59:19 +00001523 CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found
1524 after the configured retry count, the call will fail
1525 instead of starting over. This can be used to fail over
1526 to Link-local IP address configuration if the DHCP server
1527 is not available.
1528
stroesefe389a82003-08-28 14:17:32 +00001529 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
1530 to do a dynamic update of a DNS server. To do this, they
1531 need the hostname of the DHCP requester.
Wilson Callan5d110f02007-07-28 10:56:13 -04001532 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content
Jon Loeliger1fe80d72007-07-09 22:08:34 -05001533 of the "hostname" environment variable is passed as
1534 option 12 to the DHCP server.
stroesefe389a82003-08-28 14:17:32 +00001535
Aras Vaichasd9a2f412008-03-26 09:43:57 +11001536 CONFIG_BOOTP_DHCP_REQUEST_DELAY
1537
1538 A 32bit value in microseconds for a delay between
1539 receiving a "DHCP Offer" and sending the "DHCP Request".
1540 This fixes a problem with certain DHCP servers that don't
1541 respond 100% of the time to a "DHCP request". E.g. On an
1542 AT91RM9200 processor running at 180MHz, this delay needed
1543 to be *at least* 15,000 usec before a Windows Server 2003
1544 DHCP server would reply 100% of the time. I recommend at
1545 least 50,000 usec to be safe. The alternative is to hope
1546 that one of the retries will be successful but note that
1547 the DHCP timeout and retry process takes a longer than
1548 this delay.
1549
Joe Hershbergerd22c3382012-05-23 08:00:12 +00001550 - Link-local IP address negotiation:
1551 Negotiate with other link-local clients on the local network
1552 for an address that doesn't require explicit configuration.
1553 This is especially useful if a DHCP server cannot be guaranteed
1554 to exist in all environments that the device must operate.
1555
1556 See doc/README.link-local for more information.
1557
Prabhakar Kushwaha24acb832017-11-23 16:51:32 +05301558 - MAC address from environment variables
1559
1560 FDT_SEQ_MACADDR_FROM_ENV
1561
1562 Fix-up device tree with MAC addresses fetched sequentially from
1563 environment variables. This config work on assumption that
1564 non-usable ethernet node of device-tree are either not present
1565 or their status has been marked as "disabled".
1566
wdenka3d991b2004-04-15 21:48:45 +00001567 - CDP Options:
wdenk6e592382004-04-18 17:39:38 +00001568 CONFIG_CDP_DEVICE_ID
wdenka3d991b2004-04-15 21:48:45 +00001569
1570 The device id used in CDP trigger frames.
1571
1572 CONFIG_CDP_DEVICE_ID_PREFIX
1573
1574 A two character string which is prefixed to the MAC address
1575 of the device.
1576
1577 CONFIG_CDP_PORT_ID
1578
1579 A printf format string which contains the ascii name of
1580 the port. Normally is set to "eth%d" which sets
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001581 eth0 for the first Ethernet, eth1 for the second etc.
wdenka3d991b2004-04-15 21:48:45 +00001582
1583 CONFIG_CDP_CAPABILITIES
1584
1585 A 32bit integer which indicates the device capabilities;
1586 0x00000010 for a normal host which does not forwards.
1587
1588 CONFIG_CDP_VERSION
1589
1590 An ascii string containing the version of the software.
1591
1592 CONFIG_CDP_PLATFORM
1593
1594 An ascii string containing the name of the platform.
1595
1596 CONFIG_CDP_TRIGGER
1597
1598 A 32bit integer sent on the trigger.
1599
1600 CONFIG_CDP_POWER_CONSUMPTION
1601
1602 A 16bit integer containing the power consumption of the
1603 device in .1 of milliwatts.
1604
1605 CONFIG_CDP_APPLIANCE_VLAN_TYPE
1606
1607 A byte containing the id of the VLAN.
1608
Uri Mashiach79267ed2017-01-19 10:51:05 +02001609- Status LED: CONFIG_LED_STATUS
wdenkc6097192002-11-03 00:24:07 +00001610
1611 Several configurations allow to display the current
1612 status using a LED. For instance, the LED will blink
1613 fast while running U-Boot code, stop blinking as
1614 soon as a reply to a BOOTP request was received, and
1615 start blinking slow once the Linux kernel is running
1616 (supported by a status LED driver in the Linux
Uri Mashiach79267ed2017-01-19 10:51:05 +02001617 kernel). Defining CONFIG_LED_STATUS enables this
wdenkc6097192002-11-03 00:24:07 +00001618 feature in U-Boot.
1619
Igor Grinberg1df7bbb2013-11-08 01:03:50 +02001620 Additional options:
1621
Uri Mashiach79267ed2017-01-19 10:51:05 +02001622 CONFIG_LED_STATUS_GPIO
Igor Grinberg1df7bbb2013-11-08 01:03:50 +02001623 The status LED can be connected to a GPIO pin.
1624 In such cases, the gpio_led driver can be used as a
Uri Mashiach79267ed2017-01-19 10:51:05 +02001625 status LED backend implementation. Define CONFIG_LED_STATUS_GPIO
Igor Grinberg1df7bbb2013-11-08 01:03:50 +02001626 to include the gpio_led driver in the U-Boot binary.
1627
Igor Grinberg9dfdcdf2013-11-08 01:03:52 +02001628 CONFIG_GPIO_LED_INVERTED_TABLE
1629 Some GPIO connected LEDs may have inverted polarity in which
1630 case the GPIO high value corresponds to LED off state and
1631 GPIO low value corresponds to LED on state.
1632 In such cases CONFIG_GPIO_LED_INVERTED_TABLE may be defined
1633 with a list of GPIO LEDs that have inverted polarity.
1634
Heiko Schocher3f4978c2012-01-16 21:12:24 +00001635- I2C Support: CONFIG_SYS_I2C
wdenkc6097192002-11-03 00:24:07 +00001636
Heiko Schocher3f4978c2012-01-16 21:12:24 +00001637 This enable the NEW i2c subsystem, and will allow you to use
1638 i2c commands at the u-boot command line (as long as you set
1639 CONFIG_CMD_I2C in CONFIG_COMMANDS) and communicate with i2c
1640 based realtime clock chips or other i2c devices. See
1641 common/cmd_i2c.c for a description of the command line
1642 interface.
1643
1644 ported i2c driver to the new framework:
Heiko Schocherea818db2013-01-29 08:53:15 +01001645 - drivers/i2c/soft_i2c.c:
1646 - activate first bus with CONFIG_SYS_I2C_SOFT define
1647 CONFIG_SYS_I2C_SOFT_SPEED and CONFIG_SYS_I2C_SOFT_SLAVE
1648 for defining speed and slave address
1649 - activate second bus with I2C_SOFT_DECLARATIONS2 define
1650 CONFIG_SYS_I2C_SOFT_SPEED_2 and CONFIG_SYS_I2C_SOFT_SLAVE_2
1651 for defining speed and slave address
1652 - activate third bus with I2C_SOFT_DECLARATIONS3 define
1653 CONFIG_SYS_I2C_SOFT_SPEED_3 and CONFIG_SYS_I2C_SOFT_SLAVE_3
1654 for defining speed and slave address
1655 - activate fourth bus with I2C_SOFT_DECLARATIONS4 define
1656 CONFIG_SYS_I2C_SOFT_SPEED_4 and CONFIG_SYS_I2C_SOFT_SLAVE_4
1657 for defining speed and slave address
Heiko Schocher3f4978c2012-01-16 21:12:24 +00001658
Heiko Schocher00f792e2012-10-24 13:48:22 +02001659 - drivers/i2c/fsl_i2c.c:
1660 - activate i2c driver with CONFIG_SYS_I2C_FSL
1661 define CONFIG_SYS_FSL_I2C_OFFSET for setting the register
1662 offset CONFIG_SYS_FSL_I2C_SPEED for the i2c speed and
1663 CONFIG_SYS_FSL_I2C_SLAVE for the slave addr of the first
1664 bus.
Wolfgang Denk93e14592013-10-04 17:43:24 +02001665 - If your board supports a second fsl i2c bus, define
Heiko Schocher00f792e2012-10-24 13:48:22 +02001666 CONFIG_SYS_FSL_I2C2_OFFSET for the register offset
1667 CONFIG_SYS_FSL_I2C2_SPEED for the speed and
1668 CONFIG_SYS_FSL_I2C2_SLAVE for the slave address of the
1669 second bus.
1670
Simon Glass1f2ba722012-10-30 07:28:53 +00001671 - drivers/i2c/tegra_i2c.c:
Nobuhiro Iwamatsu10cee512013-10-11 16:23:53 +09001672 - activate this driver with CONFIG_SYS_I2C_TEGRA
1673 - This driver adds 4 i2c buses with a fix speed from
1674 100000 and the slave addr 0!
Simon Glass1f2ba722012-10-30 07:28:53 +00001675
Dirk Eibach880540d2013-04-25 02:40:01 +00001676 - drivers/i2c/ppc4xx_i2c.c
1677 - activate this driver with CONFIG_SYS_I2C_PPC4XX
1678 - CONFIG_SYS_I2C_PPC4XX_CH0 activate hardware channel 0
1679 - CONFIG_SYS_I2C_PPC4XX_CH1 activate hardware channel 1
1680
tremfac96402013-09-21 18:13:35 +02001681 - drivers/i2c/i2c_mxc.c
1682 - activate this driver with CONFIG_SYS_I2C_MXC
Albert ARIBAUD \\(3ADEV\\)03544c62015-09-21 22:43:38 +02001683 - enable bus 1 with CONFIG_SYS_I2C_MXC_I2C1
1684 - enable bus 2 with CONFIG_SYS_I2C_MXC_I2C2
1685 - enable bus 3 with CONFIG_SYS_I2C_MXC_I2C3
1686 - enable bus 4 with CONFIG_SYS_I2C_MXC_I2C4
tremfac96402013-09-21 18:13:35 +02001687 - define speed for bus 1 with CONFIG_SYS_MXC_I2C1_SPEED
1688 - define slave for bus 1 with CONFIG_SYS_MXC_I2C1_SLAVE
1689 - define speed for bus 2 with CONFIG_SYS_MXC_I2C2_SPEED
1690 - define slave for bus 2 with CONFIG_SYS_MXC_I2C2_SLAVE
1691 - define speed for bus 3 with CONFIG_SYS_MXC_I2C3_SPEED
1692 - define slave for bus 3 with CONFIG_SYS_MXC_I2C3_SLAVE
Albert ARIBAUD \\(3ADEV\\)03544c62015-09-21 22:43:38 +02001693 - define speed for bus 4 with CONFIG_SYS_MXC_I2C4_SPEED
1694 - define slave for bus 4 with CONFIG_SYS_MXC_I2C4_SLAVE
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08001695 If those defines are not set, default value is 100000
tremfac96402013-09-21 18:13:35 +02001696 for speed, and 0 for slave.
1697
Nobuhiro Iwamatsu1086bfa2013-09-27 16:58:30 +09001698 - drivers/i2c/rcar_i2c.c:
1699 - activate this driver with CONFIG_SYS_I2C_RCAR
1700 - This driver adds 4 i2c buses
1701
1702 - CONFIG_SYS_RCAR_I2C0_BASE for setting the register channel 0
1703 - CONFIG_SYS_RCAR_I2C0_SPEED for for the speed channel 0
1704 - CONFIG_SYS_RCAR_I2C1_BASE for setting the register channel 1
1705 - CONFIG_SYS_RCAR_I2C1_SPEED for for the speed channel 1
1706 - CONFIG_SYS_RCAR_I2C2_BASE for setting the register channel 2
1707 - CONFIG_SYS_RCAR_I2C2_SPEED for for the speed channel 2
1708 - CONFIG_SYS_RCAR_I2C3_BASE for setting the register channel 3
1709 - CONFIG_SYS_RCAR_I2C3_SPEED for for the speed channel 3
1710 - CONFIF_SYS_RCAR_I2C_NUM_CONTROLLERS for number of i2c buses
1711
Nobuhiro Iwamatsu2035d772013-10-29 13:33:51 +09001712 - drivers/i2c/sh_i2c.c:
1713 - activate this driver with CONFIG_SYS_I2C_SH
1714 - This driver adds from 2 to 5 i2c buses
1715
1716 - CONFIG_SYS_I2C_SH_BASE0 for setting the register channel 0
1717 - CONFIG_SYS_I2C_SH_SPEED0 for for the speed channel 0
1718 - CONFIG_SYS_I2C_SH_BASE1 for setting the register channel 1
1719 - CONFIG_SYS_I2C_SH_SPEED1 for for the speed channel 1
1720 - CONFIG_SYS_I2C_SH_BASE2 for setting the register channel 2
1721 - CONFIG_SYS_I2C_SH_SPEED2 for for the speed channel 2
1722 - CONFIG_SYS_I2C_SH_BASE3 for setting the register channel 3
1723 - CONFIG_SYS_I2C_SH_SPEED3 for for the speed channel 3
1724 - CONFIG_SYS_I2C_SH_BASE4 for setting the register channel 4
1725 - CONFIG_SYS_I2C_SH_SPEED4 for for the speed channel 4
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08001726 - CONFIG_SYS_I2C_SH_NUM_CONTROLLERS for number of i2c buses
Nobuhiro Iwamatsu2035d772013-10-29 13:33:51 +09001727
Heiko Schocher6789e842013-10-22 11:03:18 +02001728 - drivers/i2c/omap24xx_i2c.c
1729 - activate this driver with CONFIG_SYS_I2C_OMAP24XX
1730 - CONFIG_SYS_OMAP24_I2C_SPEED speed channel 0
1731 - CONFIG_SYS_OMAP24_I2C_SLAVE slave addr channel 0
1732 - CONFIG_SYS_OMAP24_I2C_SPEED1 speed channel 1
1733 - CONFIG_SYS_OMAP24_I2C_SLAVE1 slave addr channel 1
1734 - CONFIG_SYS_OMAP24_I2C_SPEED2 speed channel 2
1735 - CONFIG_SYS_OMAP24_I2C_SLAVE2 slave addr channel 2
1736 - CONFIG_SYS_OMAP24_I2C_SPEED3 speed channel 3
1737 - CONFIG_SYS_OMAP24_I2C_SLAVE3 slave addr channel 3
1738 - CONFIG_SYS_OMAP24_I2C_SPEED4 speed channel 4
1739 - CONFIG_SYS_OMAP24_I2C_SLAVE4 slave addr channel 4
1740
Heiko Schocher0bdffe72013-11-08 07:30:53 +01001741 - drivers/i2c/zynq_i2c.c
1742 - activate this driver with CONFIG_SYS_I2C_ZYNQ
1743 - set CONFIG_SYS_I2C_ZYNQ_SPEED for speed setting
1744 - set CONFIG_SYS_I2C_ZYNQ_SLAVE for slave addr
1745
Naveen Krishna Che717fc62013-12-06 12:12:38 +05301746 - drivers/i2c/s3c24x0_i2c.c:
1747 - activate this driver with CONFIG_SYS_I2C_S3C24X0
1748 - This driver adds i2c buses (11 for Exynos5250, Exynos5420
1749 9 i2c buses for Exynos4 and 1 for S3C24X0 SoCs from Samsung)
1750 with a fix speed from 100000 and the slave addr 0!
1751
Dirk Eibachb46226b2014-07-03 09:28:18 +02001752 - drivers/i2c/ihs_i2c.c
1753 - activate this driver with CONFIG_SYS_I2C_IHS
1754 - CONFIG_SYS_I2C_IHS_CH0 activate hardware channel 0
1755 - CONFIG_SYS_I2C_IHS_SPEED_0 speed channel 0
1756 - CONFIG_SYS_I2C_IHS_SLAVE_0 slave addr channel 0
1757 - CONFIG_SYS_I2C_IHS_CH1 activate hardware channel 1
1758 - CONFIG_SYS_I2C_IHS_SPEED_1 speed channel 1
1759 - CONFIG_SYS_I2C_IHS_SLAVE_1 slave addr channel 1
1760 - CONFIG_SYS_I2C_IHS_CH2 activate hardware channel 2
1761 - CONFIG_SYS_I2C_IHS_SPEED_2 speed channel 2
1762 - CONFIG_SYS_I2C_IHS_SLAVE_2 slave addr channel 2
1763 - CONFIG_SYS_I2C_IHS_CH3 activate hardware channel 3
1764 - CONFIG_SYS_I2C_IHS_SPEED_3 speed channel 3
1765 - CONFIG_SYS_I2C_IHS_SLAVE_3 slave addr channel 3
Dirk Eibach071be892015-10-28 11:46:22 +01001766 - activate dual channel with CONFIG_SYS_I2C_IHS_DUAL
1767 - CONFIG_SYS_I2C_IHS_SPEED_0_1 speed channel 0_1
1768 - CONFIG_SYS_I2C_IHS_SLAVE_0_1 slave addr channel 0_1
1769 - CONFIG_SYS_I2C_IHS_SPEED_1_1 speed channel 1_1
1770 - CONFIG_SYS_I2C_IHS_SLAVE_1_1 slave addr channel 1_1
1771 - CONFIG_SYS_I2C_IHS_SPEED_2_1 speed channel 2_1
1772 - CONFIG_SYS_I2C_IHS_SLAVE_2_1 slave addr channel 2_1
1773 - CONFIG_SYS_I2C_IHS_SPEED_3_1 speed channel 3_1
1774 - CONFIG_SYS_I2C_IHS_SLAVE_3_1 slave addr channel 3_1
Dirk Eibachb46226b2014-07-03 09:28:18 +02001775
Heiko Schocher3f4978c2012-01-16 21:12:24 +00001776 additional defines:
1777
1778 CONFIG_SYS_NUM_I2C_BUSES
Simon Glass945a18e2016-10-02 18:01:05 -06001779 Hold the number of i2c buses you want to use.
Heiko Schocher3f4978c2012-01-16 21:12:24 +00001780
1781 CONFIG_SYS_I2C_DIRECT_BUS
1782 define this, if you don't use i2c muxes on your hardware.
1783 if CONFIG_SYS_I2C_MAX_HOPS is not defined or == 0 you can
1784 omit this define.
1785
1786 CONFIG_SYS_I2C_MAX_HOPS
1787 define how many muxes are maximal consecutively connected
1788 on one i2c bus. If you not use i2c muxes, omit this
1789 define.
1790
1791 CONFIG_SYS_I2C_BUSES
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08001792 hold a list of buses you want to use, only used if
Heiko Schocher3f4978c2012-01-16 21:12:24 +00001793 CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example
1794 a board with CONFIG_SYS_I2C_MAX_HOPS = 1 and
1795 CONFIG_SYS_NUM_I2C_BUSES = 9:
1796
1797 CONFIG_SYS_I2C_BUSES {{0, {I2C_NULL_HOP}}, \
1798 {0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \
1799 {0, {{I2C_MUX_PCA9547, 0x70, 2}}}, \
1800 {0, {{I2C_MUX_PCA9547, 0x70, 3}}}, \
1801 {0, {{I2C_MUX_PCA9547, 0x70, 4}}}, \
1802 {0, {{I2C_MUX_PCA9547, 0x70, 5}}}, \
1803 {1, {I2C_NULL_HOP}}, \
1804 {1, {{I2C_MUX_PCA9544, 0x72, 1}}}, \
1805 {1, {{I2C_MUX_PCA9544, 0x72, 2}}}, \
1806 }
1807
1808 which defines
1809 bus 0 on adapter 0 without a mux
Heiko Schocherea818db2013-01-29 08:53:15 +01001810 bus 1 on adapter 0 with a PCA9547 on address 0x70 port 1
1811 bus 2 on adapter 0 with a PCA9547 on address 0x70 port 2
1812 bus 3 on adapter 0 with a PCA9547 on address 0x70 port 3
1813 bus 4 on adapter 0 with a PCA9547 on address 0x70 port 4
1814 bus 5 on adapter 0 with a PCA9547 on address 0x70 port 5
Heiko Schocher3f4978c2012-01-16 21:12:24 +00001815 bus 6 on adapter 1 without a mux
Heiko Schocherea818db2013-01-29 08:53:15 +01001816 bus 7 on adapter 1 with a PCA9544 on address 0x72 port 1
1817 bus 8 on adapter 1 with a PCA9544 on address 0x72 port 2
Heiko Schocher3f4978c2012-01-16 21:12:24 +00001818
1819 If you do not have i2c muxes on your board, omit this define.
1820
Simon Glassce3b5d62017-05-12 21:10:00 -06001821- Legacy I2C Support:
Heiko Schocherea818db2013-01-29 08:53:15 +01001822 If you use the software i2c interface (CONFIG_SYS_I2C_SOFT)
wdenkb37c7e52003-06-30 16:24:52 +00001823 then the following macros need to be defined (examples are
1824 from include/configs/lwmon.h):
wdenkc6097192002-11-03 00:24:07 +00001825
1826 I2C_INIT
1827
wdenkb37c7e52003-06-30 16:24:52 +00001828 (Optional). Any commands necessary to enable the I2C
wdenk43d96162003-03-06 00:02:04 +00001829 controller or configure ports.
wdenkc6097192002-11-03 00:24:07 +00001830
wdenkba56f622004-02-06 23:19:44 +00001831 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
wdenkb37c7e52003-06-30 16:24:52 +00001832
wdenkc6097192002-11-03 00:24:07 +00001833 I2C_ACTIVE
1834
1835 The code necessary to make the I2C data line active
1836 (driven). If the data line is open collector, this
1837 define can be null.
1838
wdenkb37c7e52003-06-30 16:24:52 +00001839 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
1840
wdenkc6097192002-11-03 00:24:07 +00001841 I2C_TRISTATE
1842
1843 The code necessary to make the I2C data line tri-stated
1844 (inactive). If the data line is open collector, this
1845 define can be null.
1846
wdenkb37c7e52003-06-30 16:24:52 +00001847 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
1848
wdenkc6097192002-11-03 00:24:07 +00001849 I2C_READ
1850
York Sun472d5462013-04-01 11:29:11 -07001851 Code that returns true if the I2C data line is high,
1852 false if it is low.
wdenkc6097192002-11-03 00:24:07 +00001853
wdenkb37c7e52003-06-30 16:24:52 +00001854 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
1855
wdenkc6097192002-11-03 00:24:07 +00001856 I2C_SDA(bit)
1857
York Sun472d5462013-04-01 11:29:11 -07001858 If <bit> is true, sets the I2C data line high. If it
1859 is false, it clears it (low).
wdenkc6097192002-11-03 00:24:07 +00001860
wdenkb37c7e52003-06-30 16:24:52 +00001861 eg: #define I2C_SDA(bit) \
wdenk2535d602003-07-17 23:16:40 +00001862 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
wdenkba56f622004-02-06 23:19:44 +00001863 else immr->im_cpm.cp_pbdat &= ~PB_SDA
wdenkb37c7e52003-06-30 16:24:52 +00001864
wdenkc6097192002-11-03 00:24:07 +00001865 I2C_SCL(bit)
1866
York Sun472d5462013-04-01 11:29:11 -07001867 If <bit> is true, sets the I2C clock line high. If it
1868 is false, it clears it (low).
wdenkc6097192002-11-03 00:24:07 +00001869
wdenkb37c7e52003-06-30 16:24:52 +00001870 eg: #define I2C_SCL(bit) \
wdenk2535d602003-07-17 23:16:40 +00001871 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
wdenkba56f622004-02-06 23:19:44 +00001872 else immr->im_cpm.cp_pbdat &= ~PB_SCL
wdenkb37c7e52003-06-30 16:24:52 +00001873
wdenkc6097192002-11-03 00:24:07 +00001874 I2C_DELAY
1875
1876 This delay is invoked four times per clock cycle so this
1877 controls the rate of data transfer. The data rate thus
wdenkb37c7e52003-06-30 16:24:52 +00001878 is 1 / (I2C_DELAY * 4). Often defined to be something
wdenk945af8d2003-07-16 21:53:01 +00001879 like:
1880
wdenkb37c7e52003-06-30 16:24:52 +00001881 #define I2C_DELAY udelay(2)
wdenkc6097192002-11-03 00:24:07 +00001882
Mike Frysinger793b5722010-07-21 13:38:02 -04001883 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA
1884
1885 If your arch supports the generic GPIO framework (asm/gpio.h),
1886 then you may alternatively define the two GPIOs that are to be
1887 used as SCL / SDA. Any of the previous I2C_xxx macros will
1888 have GPIO-based defaults assigned to them as appropriate.
1889
1890 You should define these to the GPIO value as given directly to
1891 the generic GPIO functions.
1892
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001893 CONFIG_SYS_I2C_INIT_BOARD
wdenk47cd00f2003-03-06 13:39:27 +00001894
wdenk8bde7f72003-06-27 21:31:46 +00001895 When a board is reset during an i2c bus transfer
1896 chips might think that the current transfer is still
1897 in progress. On some boards it is possible to access
1898 the i2c SCLK line directly, either by using the
1899 processor pin as a GPIO or by having a second pin
1900 connected to the bus. If this option is defined a
1901 custom i2c_init_board() routine in boards/xxx/board.c
1902 is run early in the boot sequence.
wdenk47cd00f2003-03-06 13:39:27 +00001903
Ben Warrenbb99ad62006-09-07 16:50:54 -04001904 CONFIG_I2C_MULTI_BUS
1905
1906 This option allows the use of multiple I2C buses, each of which
Wolfgang Denkc0f40852011-10-26 10:21:21 +00001907 must have a controller. At any point in time, only one bus is
1908 active. To switch to a different bus, use the 'i2c dev' command.
Ben Warrenbb99ad62006-09-07 16:50:54 -04001909 Note that bus numbering is zero-based.
1910
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001911 CONFIG_SYS_I2C_NOPROBES
Ben Warrenbb99ad62006-09-07 16:50:54 -04001912
1913 This option specifies a list of I2C devices that will be skipped
Wolfgang Denkc0f40852011-10-26 10:21:21 +00001914 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS
Peter Tyser0f89c542009-04-18 22:34:03 -05001915 is set, specify a list of bus-device pairs. Otherwise, specify
1916 a 1D array of device addresses
Ben Warrenbb99ad62006-09-07 16:50:54 -04001917
1918 e.g.
1919 #undef CONFIG_I2C_MULTI_BUS
Wolfgang Denkc0f40852011-10-26 10:21:21 +00001920 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68}
Ben Warrenbb99ad62006-09-07 16:50:54 -04001921
1922 will skip addresses 0x50 and 0x68 on a board with one I2C bus
1923
Wolfgang Denkc0f40852011-10-26 10:21:21 +00001924 #define CONFIG_I2C_MULTI_BUS
Simon Glass945a18e2016-10-02 18:01:05 -06001925 #define CONFIG_SYS_I2C_NOPROBES {{0,0x50},{0,0x68},{1,0x54}}
Ben Warrenbb99ad62006-09-07 16:50:54 -04001926
1927 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1
1928
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001929 CONFIG_SYS_SPD_BUS_NUM
Timur Tabibe5e6182006-11-03 19:15:00 -06001930
1931 If defined, then this indicates the I2C bus number for DDR SPD.
1932 If not defined, then U-Boot assumes that SPD is on I2C bus 0.
1933
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001934 CONFIG_SYS_RTC_BUS_NUM
Stefan Roese0dc018e2007-02-20 10:51:26 +01001935
1936 If defined, then this indicates the I2C bus number for the RTC.
1937 If not defined, then U-Boot assumes that RTC is on I2C bus 0.
1938
Andrew Dyer2ac69852008-12-29 17:36:01 -06001939 CONFIG_SOFT_I2C_READ_REPEATED_START
1940
1941 defining this will force the i2c_read() function in
1942 the soft_i2c driver to perform an I2C repeated start
1943 between writing the address pointer and reading the
1944 data. If this define is omitted the default behaviour
1945 of doing a stop-start sequence will be used. Most I2C
1946 devices can use either method, but some require one or
1947 the other.
Timur Tabibe5e6182006-11-03 19:15:00 -06001948
wdenkc6097192002-11-03 00:24:07 +00001949- SPI Support: CONFIG_SPI
1950
1951 Enables SPI driver (so far only tested with
1952 SPI EEPROM, also an instance works with Crystal A/D and
1953 D/As on the SACSng board)
1954
wdenkc6097192002-11-03 00:24:07 +00001955 CONFIG_SOFT_SPI
1956
wdenk43d96162003-03-06 00:02:04 +00001957 Enables a software (bit-bang) SPI driver rather than
1958 using hardware support. This is a general purpose
1959 driver that only requires three general I/O port pins
1960 (two outputs, one input) to function. If this is
1961 defined, the board configuration must define several
1962 SPI configuration items (port pins to use, etc). For
1963 an example, see include/configs/sacsng.h.
wdenkc6097192002-11-03 00:24:07 +00001964
Ben Warren04a9e112008-01-16 22:37:35 -05001965 CONFIG_HARD_SPI
1966
1967 Enables a hardware SPI driver for general-purpose reads
1968 and writes. As with CONFIG_SOFT_SPI, the board configuration
1969 must define a list of chip-select function pointers.
Wolfgang Denkc0f40852011-10-26 10:21:21 +00001970 Currently supported on some MPC8xxx processors. For an
Ben Warren04a9e112008-01-16 22:37:35 -05001971 example, see include/configs/mpc8349emds.h.
1972
Heiko Schocherf659b572014-07-14 10:22:11 +02001973 CONFIG_SYS_SPI_MXC_WAIT
1974 Timeout for waiting until spi transfer completed.
1975 default: (CONFIG_SYS_HZ/100) /* 10 ms */
1976
Matthias Fuchs01335022007-12-27 17:12:34 +01001977- FPGA Support: CONFIG_FPGA
1978
1979 Enables FPGA subsystem.
1980
1981 CONFIG_FPGA_<vendor>
1982
1983 Enables support for specific chip vendors.
1984 (ALTERA, XILINX)
1985
1986 CONFIG_FPGA_<family>
1987
1988 Enables support for FPGA family.
1989 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
1990
1991 CONFIG_FPGA_COUNT
wdenkc6097192002-11-03 00:24:07 +00001992
wdenk43d96162003-03-06 00:02:04 +00001993 Specify the number of FPGA devices to support.
wdenkc6097192002-11-03 00:24:07 +00001994
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001995 CONFIG_SYS_FPGA_PROG_FEEDBACK
wdenkc6097192002-11-03 00:24:07 +00001996
wdenk8bde7f72003-06-27 21:31:46 +00001997 Enable printing of hash marks during FPGA configuration.
wdenkc6097192002-11-03 00:24:07 +00001998
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001999 CONFIG_SYS_FPGA_CHECK_BUSY
wdenkc6097192002-11-03 00:24:07 +00002000
wdenk43d96162003-03-06 00:02:04 +00002001 Enable checks on FPGA configuration interface busy
2002 status by the configuration function. This option
2003 will require a board or device specific function to
2004 be written.
wdenkc6097192002-11-03 00:24:07 +00002005
2006 CONFIG_FPGA_DELAY
2007
2008 If defined, a function that provides delays in the FPGA
2009 configuration driver.
2010
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002011 CONFIG_SYS_FPGA_CHECK_CTRLC
wdenkc6097192002-11-03 00:24:07 +00002012 Allow Control-C to interrupt FPGA configuration
2013
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002014 CONFIG_SYS_FPGA_CHECK_ERROR
wdenkc6097192002-11-03 00:24:07 +00002015
wdenk43d96162003-03-06 00:02:04 +00002016 Check for configuration errors during FPGA bitfile
2017 loading. For example, abort during Virtex II
2018 configuration if the INIT_B line goes low (which
2019 indicated a CRC error).
wdenkc6097192002-11-03 00:24:07 +00002020
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002021 CONFIG_SYS_FPGA_WAIT_INIT
wdenkc6097192002-11-03 00:24:07 +00002022
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08002023 Maximum time to wait for the INIT_B line to de-assert
2024 after PROB_B has been de-asserted during a Virtex II
wdenk43d96162003-03-06 00:02:04 +00002025 FPGA configuration sequence. The default time is 500
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002026 ms.
wdenkc6097192002-11-03 00:24:07 +00002027
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002028 CONFIG_SYS_FPGA_WAIT_BUSY
wdenkc6097192002-11-03 00:24:07 +00002029
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08002030 Maximum time to wait for BUSY to de-assert during
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002031 Virtex II FPGA configuration. The default is 5 ms.
wdenkc6097192002-11-03 00:24:07 +00002032
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002033 CONFIG_SYS_FPGA_WAIT_CONFIG
wdenkc6097192002-11-03 00:24:07 +00002034
wdenk43d96162003-03-06 00:02:04 +00002035 Time to wait after FPGA configuration. The default is
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002036 200 ms.
wdenkc6097192002-11-03 00:24:07 +00002037
2038- Configuration Management:
Stefan Roeseb2b8a692014-10-22 12:13:24 +02002039 CONFIG_BUILD_TARGET
2040
2041 Some SoCs need special image types (e.g. U-Boot binary
2042 with a special header) as build targets. By defining
2043 CONFIG_BUILD_TARGET in the SoC / board header, this
2044 special image will be automatically built upon calling
Simon Glass6de80f22016-07-27 20:33:08 -06002045 make / buildman.
Stefan Roeseb2b8a692014-10-22 12:13:24 +02002046
wdenkc6097192002-11-03 00:24:07 +00002047 CONFIG_IDENT_STRING
2048
wdenk43d96162003-03-06 00:02:04 +00002049 If defined, this string will be added to the U-Boot
2050 version information (U_BOOT_VERSION)
wdenkc6097192002-11-03 00:24:07 +00002051
2052- Vendor Parameter Protection:
2053
wdenk43d96162003-03-06 00:02:04 +00002054 U-Boot considers the values of the environment
2055 variables "serial#" (Board Serial Number) and
wdenk7152b1d2003-09-05 23:19:14 +00002056 "ethaddr" (Ethernet Address) to be parameters that
wdenk43d96162003-03-06 00:02:04 +00002057 are set once by the board vendor / manufacturer, and
2058 protects these variables from casual modification by
2059 the user. Once set, these variables are read-only,
2060 and write or delete attempts are rejected. You can
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002061 change this behaviour:
wdenkc6097192002-11-03 00:24:07 +00002062
2063 If CONFIG_ENV_OVERWRITE is #defined in your config
2064 file, the write protection for vendor parameters is
wdenk47cd00f2003-03-06 13:39:27 +00002065 completely disabled. Anybody can change or delete
wdenkc6097192002-11-03 00:24:07 +00002066 these parameters.
2067
Joe Hershberger92ac5202015-05-04 14:55:14 -05002068 Alternatively, if you define _both_ an ethaddr in the
2069 default env _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002070 Ethernet address is installed in the environment,
wdenkc6097192002-11-03 00:24:07 +00002071 which can be changed exactly ONCE by the user. [The
2072 serial# is unaffected by this, i. e. it remains
2073 read-only.]
2074
Joe Hershberger25980902012-12-11 22:16:31 -06002075 The same can be accomplished in a more flexible way
2076 for any variable by configuring the type of access
2077 to allow for those variables in the ".flags" variable
2078 or define CONFIG_ENV_FLAGS_LIST_STATIC.
2079
wdenkc6097192002-11-03 00:24:07 +00002080- Protected RAM:
2081 CONFIG_PRAM
2082
2083 Define this variable to enable the reservation of
2084 "protected RAM", i. e. RAM which is not overwritten
2085 by U-Boot. Define CONFIG_PRAM to hold the number of
2086 kB you want to reserve for pRAM. You can overwrite
2087 this default value by defining an environment
2088 variable "pram" to the number of kB you want to
2089 reserve. Note that the board info structure will
2090 still show the full amount of RAM. If pRAM is
2091 reserved, a new environment variable "mem" will
2092 automatically be defined to hold the amount of
2093 remaining RAM in a form that can be passed as boot
2094 argument to Linux, for instance like that:
2095
Wolfgang Denkfe126d82005-11-20 21:40:11 +01002096 setenv bootargs ... mem=\${mem}
wdenkc6097192002-11-03 00:24:07 +00002097 saveenv
2098
2099 This way you can tell Linux not to use this memory,
2100 either, which results in a memory region that will
2101 not be affected by reboots.
2102
2103 *WARNING* If your board configuration uses automatic
2104 detection of the RAM size, you must make sure that
2105 this memory test is non-destructive. So far, the
2106 following board configurations are known to be
2107 "pRAM-clean":
2108
Heiko Schocher5b8e76c2017-06-07 17:33:09 +02002109 IVMS8, IVML24, SPD8xx,
Wolfgang Denk1b0757e2012-10-24 02:36:15 +00002110 HERMES, IP860, RPXlite, LWMON,
Heiko Schocher2eb48ff2017-06-07 17:33:10 +02002111 FLAGADM
wdenkc6097192002-11-03 00:24:07 +00002112
Gabe Black40fef042012-12-02 04:55:18 +00002113- Access to physical memory region (> 4GB)
2114 Some basic support is provided for operations on memory not
2115 normally accessible to U-Boot - e.g. some architectures
2116 support access to more than 4GB of memory on 32-bit
2117 machines using physical address extension or similar.
2118 Define CONFIG_PHYSMEM to access this basic support, which
2119 currently only supports clearing the memory.
2120
wdenkc6097192002-11-03 00:24:07 +00002121- Error Recovery:
wdenkc6097192002-11-03 00:24:07 +00002122 CONFIG_NET_RETRY_COUNT
2123
wdenk43d96162003-03-06 00:02:04 +00002124 This variable defines the number of retries for
2125 network operations like ARP, RARP, TFTP, or BOOTP
2126 before giving up the operation. If not defined, a
2127 default value of 5 is used.
wdenkc6097192002-11-03 00:24:07 +00002128
Guennadi Liakhovetski40cb90e2008-04-03 17:04:19 +02002129 CONFIG_ARP_TIMEOUT
2130
2131 Timeout waiting for an ARP reply in milliseconds.
2132
Tetsuyuki Kobayashi48a3e992012-07-03 22:25:21 +00002133 CONFIG_NFS_TIMEOUT
2134
2135 Timeout in milliseconds used in NFS protocol.
2136 If you encounter "ERROR: Cannot umount" in nfs command,
2137 try longer timeout such as
2138 #define CONFIG_NFS_TIMEOUT 10000UL
2139
wdenkc6097192002-11-03 00:24:07 +00002140- Command Interpreter:
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002141 CONFIG_SYS_PROMPT_HUSH_PS2
wdenkc6097192002-11-03 00:24:07 +00002142
2143 This defines the secondary prompt string, which is
2144 printed when the command interpreter needs more input
2145 to complete a command. Usually "> ".
2146
2147 Note:
2148
wdenk8bde7f72003-06-27 21:31:46 +00002149 In the current implementation, the local variables
2150 space and global environment variables space are
2151 separated. Local variables are those you define by
2152 simply typing `name=value'. To access a local
2153 variable later on, you have write `$name' or
2154 `${name}'; to execute the contents of a variable
2155 directly type `$name' at the command prompt.
wdenkc6097192002-11-03 00:24:07 +00002156
wdenk43d96162003-03-06 00:02:04 +00002157 Global environment variables are those you use
2158 setenv/printenv to work with. To run a command stored
2159 in such a variable, you need to use the run command,
2160 and you must not use the '$' sign to access them.
wdenkc6097192002-11-03 00:24:07 +00002161
2162 To store commands and special characters in a
2163 variable, please use double quotation marks
2164 surrounding the whole text of the variable, instead
2165 of the backslashes before semicolons and special
2166 symbols.
2167
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08002168- Command Line Editing and History:
Marek Vasutf3b267b2016-01-27 04:47:55 +01002169 CONFIG_CMDLINE_PS_SUPPORT
2170
2171 Enable support for changing the command prompt string
2172 at run-time. Only static string is supported so far.
2173 The string is obtained from environment variables PS1
2174 and PS2.
2175
wdenka8c7c702003-12-06 19:49:23 +00002176- Default Environment:
wdenkc6097192002-11-03 00:24:07 +00002177 CONFIG_EXTRA_ENV_SETTINGS
2178
wdenk43d96162003-03-06 00:02:04 +00002179 Define this to contain any number of null terminated
2180 strings (variable = value pairs) that will be part of
wdenk7152b1d2003-09-05 23:19:14 +00002181 the default environment compiled into the boot image.
wdenk2262cfe2002-11-18 00:14:45 +00002182
wdenk43d96162003-03-06 00:02:04 +00002183 For example, place something like this in your
2184 board's config file:
wdenkc6097192002-11-03 00:24:07 +00002185
2186 #define CONFIG_EXTRA_ENV_SETTINGS \
2187 "myvar1=value1\0" \
2188 "myvar2=value2\0"
2189
wdenk43d96162003-03-06 00:02:04 +00002190 Warning: This method is based on knowledge about the
2191 internal format how the environment is stored by the
2192 U-Boot code. This is NOT an official, exported
2193 interface! Although it is unlikely that this format
wdenk7152b1d2003-09-05 23:19:14 +00002194 will change soon, there is no guarantee either.
wdenkc6097192002-11-03 00:24:07 +00002195 You better know what you are doing here.
2196
wdenk43d96162003-03-06 00:02:04 +00002197 Note: overly (ab)use of the default environment is
2198 discouraged. Make sure to check other ways to preset
Wolfgang Denk74de7ae2009-04-01 23:34:12 +02002199 the environment like the "source" command or the
wdenk43d96162003-03-06 00:02:04 +00002200 boot command first.
wdenkc6097192002-11-03 00:24:07 +00002201
Simon Glass06fd8532012-11-30 13:01:17 +00002202 CONFIG_DELAY_ENVIRONMENT
2203
2204 Normally the environment is loaded when the board is
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08002205 initialised so that it is available to U-Boot. This inhibits
Simon Glass06fd8532012-11-30 13:01:17 +00002206 that so that the environment is not available until
2207 explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL
2208 this is instead controlled by the value of
2209 /config/load-environment.
2210
Eric Nelsonf61ec452012-01-31 10:52:08 -07002211- Serial Flash support
Simon Glass00fd59d2017-08-04 16:35:06 -06002212 Usage requires an initial 'sf probe' to define the serial
Eric Nelsonf61ec452012-01-31 10:52:08 -07002213 flash parameters, followed by read/write/erase/update
2214 commands.
2215
2216 The following defaults may be provided by the platform
2217 to handle the common case when only a single serial
2218 flash is present on the system.
2219
2220 CONFIG_SF_DEFAULT_BUS Bus identifier
2221 CONFIG_SF_DEFAULT_CS Chip-select
2222 CONFIG_SF_DEFAULT_MODE (see include/spi.h)
2223 CONFIG_SF_DEFAULT_SPEED in Hz
2224
wdenk3f85ce22004-02-23 16:11:30 +00002225
Wolfgang Denkecb0ccd2005-09-24 22:37:32 +02002226- TFTP Fixed UDP Port:
2227 CONFIG_TFTP_PORT
2228
Wolfgang Denk28cb9372005-09-24 23:25:46 +02002229 If this is defined, the environment variable tftpsrcp
Wolfgang Denkecb0ccd2005-09-24 22:37:32 +02002230 is used to supply the TFTP UDP source port value.
Wolfgang Denk28cb9372005-09-24 23:25:46 +02002231 If tftpsrcp isn't defined, the normal pseudo-random port
Wolfgang Denkecb0ccd2005-09-24 22:37:32 +02002232 number generator is used.
2233
Wolfgang Denk28cb9372005-09-24 23:25:46 +02002234 Also, the environment variable tftpdstp is used to supply
2235 the TFTP UDP destination port value. If tftpdstp isn't
2236 defined, the normal port 69 is used.
2237
2238 The purpose for tftpsrcp is to allow a TFTP server to
Wolfgang Denkecb0ccd2005-09-24 22:37:32 +02002239 blindly start the TFTP transfer using the pre-configured
2240 target IP address and UDP port. This has the effect of
2241 "punching through" the (Windows XP) firewall, allowing
2242 the remainder of the TFTP transfer to proceed normally.
2243 A better solution is to properly configure the firewall,
2244 but sometimes that is not allowed.
2245
wdenka8c7c702003-12-06 19:49:23 +00002246- Show boot progress:
wdenkc6097192002-11-03 00:24:07 +00002247 CONFIG_SHOW_BOOT_PROGRESS
2248
wdenk43d96162003-03-06 00:02:04 +00002249 Defining this option allows to add some board-
2250 specific code (calling a user-provided function
2251 "show_boot_progress(int)") that enables you to show
2252 the system's boot progress on some display (for
2253 example, some LED's) on your board. At the moment,
2254 the following checkpoints are implemented:
wdenkc6097192002-11-03 00:24:07 +00002255
Simon Glass94fd1312012-09-28 08:56:37 +00002256
Marian Balakowicz1372cce2008-03-12 10:33:01 +01002257Legacy uImage format:
2258
wdenkc6097192002-11-03 00:24:07 +00002259 Arg Where When
2260 1 common/cmd_bootm.c before attempting to boot an image
wdenkba56f622004-02-06 23:19:44 +00002261 -1 common/cmd_bootm.c Image header has bad magic number
wdenkc6097192002-11-03 00:24:07 +00002262 2 common/cmd_bootm.c Image header has correct magic number
wdenkba56f622004-02-06 23:19:44 +00002263 -2 common/cmd_bootm.c Image header has bad checksum
wdenkc6097192002-11-03 00:24:07 +00002264 3 common/cmd_bootm.c Image header has correct checksum
wdenkba56f622004-02-06 23:19:44 +00002265 -3 common/cmd_bootm.c Image data has bad checksum
wdenkc6097192002-11-03 00:24:07 +00002266 4 common/cmd_bootm.c Image data has correct checksum
2267 -4 common/cmd_bootm.c Image is for unsupported architecture
2268 5 common/cmd_bootm.c Architecture check OK
Marian Balakowicz1372cce2008-03-12 10:33:01 +01002269 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi)
wdenkc6097192002-11-03 00:24:07 +00002270 6 common/cmd_bootm.c Image Type check OK
2271 -6 common/cmd_bootm.c gunzip uncompression error
2272 -7 common/cmd_bootm.c Unimplemented compression type
2273 7 common/cmd_bootm.c Uncompression OK
Marian Balakowicz1372cce2008-03-12 10:33:01 +01002274 8 common/cmd_bootm.c No uncompress/copy overwrite error
wdenkc6097192002-11-03 00:24:07 +00002275 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
Marian Balakowicz1372cce2008-03-12 10:33:01 +01002276
2277 9 common/image.c Start initial ramdisk verification
2278 -10 common/image.c Ramdisk header has bad magic number
2279 -11 common/image.c Ramdisk header has bad checksum
2280 10 common/image.c Ramdisk header is OK
2281 -12 common/image.c Ramdisk data has bad checksum
2282 11 common/image.c Ramdisk data has correct checksum
2283 12 common/image.c Ramdisk verification complete, start loading
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002284 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk)
Marian Balakowicz1372cce2008-03-12 10:33:01 +01002285 13 common/image.c Start multifile image verification
2286 14 common/image.c No initial ramdisk, no multifile, continue.
2287
Wolfgang Denkc0f40852011-10-26 10:21:21 +00002288 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS
wdenkc6097192002-11-03 00:24:07 +00002289
Stefan Roesea47a12b2010-04-15 16:07:28 +02002290 -30 arch/powerpc/lib/board.c Fatal error, hang the system
wdenk11dadd52004-02-27 00:07:27 +00002291 -31 post/post.c POST test failed, detected by post_output_backlog()
2292 -32 post/post.c POST test failed, detected by post_run_single()
wdenk63e73c92004-02-23 22:22:28 +00002293
Heiko Schocher566a4942007-06-22 19:11:54 +02002294 34 common/cmd_doc.c before loading a Image from a DOC device
2295 -35 common/cmd_doc.c Bad usage of "doc" command
2296 35 common/cmd_doc.c correct usage of "doc" command
2297 -36 common/cmd_doc.c No boot device
2298 36 common/cmd_doc.c correct boot device
2299 -37 common/cmd_doc.c Unknown Chip ID on boot device
2300 37 common/cmd_doc.c correct chip ID found, device available
2301 -38 common/cmd_doc.c Read Error on boot device
2302 38 common/cmd_doc.c reading Image header from DOC device OK
2303 -39 common/cmd_doc.c Image header has bad magic number
2304 39 common/cmd_doc.c Image header has correct magic number
2305 -40 common/cmd_doc.c Error reading Image from DOC device
2306 40 common/cmd_doc.c Image header has correct magic number
2307 41 common/cmd_ide.c before loading a Image from a IDE device
2308 -42 common/cmd_ide.c Bad usage of "ide" command
2309 42 common/cmd_ide.c correct usage of "ide" command
2310 -43 common/cmd_ide.c No boot device
2311 43 common/cmd_ide.c boot device found
2312 -44 common/cmd_ide.c Device not available
2313 44 common/cmd_ide.c Device available
2314 -45 common/cmd_ide.c wrong partition selected
2315 45 common/cmd_ide.c partition selected
2316 -46 common/cmd_ide.c Unknown partition table
2317 46 common/cmd_ide.c valid partition table found
2318 -47 common/cmd_ide.c Invalid partition type
2319 47 common/cmd_ide.c correct partition type
2320 -48 common/cmd_ide.c Error reading Image Header on boot device
2321 48 common/cmd_ide.c reading Image Header from IDE device OK
2322 -49 common/cmd_ide.c Image header has bad magic number
2323 49 common/cmd_ide.c Image header has correct magic number
2324 -50 common/cmd_ide.c Image header has bad checksum
2325 50 common/cmd_ide.c Image header has correct checksum
2326 -51 common/cmd_ide.c Error reading Image from IDE device
2327 51 common/cmd_ide.c reading Image from IDE device OK
2328 52 common/cmd_nand.c before loading a Image from a NAND device
2329 -53 common/cmd_nand.c Bad usage of "nand" command
2330 53 common/cmd_nand.c correct usage of "nand" command
2331 -54 common/cmd_nand.c No boot device
2332 54 common/cmd_nand.c boot device found
2333 -55 common/cmd_nand.c Unknown Chip ID on boot device
2334 55 common/cmd_nand.c correct chip ID found, device available
2335 -56 common/cmd_nand.c Error reading Image Header on boot device
2336 56 common/cmd_nand.c reading Image Header from NAND device OK
2337 -57 common/cmd_nand.c Image header has bad magic number
2338 57 common/cmd_nand.c Image header has correct magic number
2339 -58 common/cmd_nand.c Error reading Image from NAND device
2340 58 common/cmd_nand.c reading Image from NAND device OK
wdenkc6097192002-11-03 00:24:07 +00002341
Heiko Schocher566a4942007-06-22 19:11:54 +02002342 -60 common/env_common.c Environment has a bad CRC, using default
wdenkc6097192002-11-03 00:24:07 +00002343
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002344 64 net/eth.c starting with Ethernet configuration.
Heiko Schocher566a4942007-06-22 19:11:54 +02002345 -64 net/eth.c no Ethernet found.
2346 65 net/eth.c Ethernet found.
wdenk206c60c2003-09-18 10:02:25 +00002347
Heiko Schocher566a4942007-06-22 19:11:54 +02002348 -80 common/cmd_net.c usage wrong
Joe Hershbergerbc0571f2015-04-08 01:41:21 -05002349 80 common/cmd_net.c before calling net_loop()
2350 -81 common/cmd_net.c some error in net_loop() occurred
2351 81 common/cmd_net.c net_loop() back without error
Heiko Schocher566a4942007-06-22 19:11:54 +02002352 -82 common/cmd_net.c size == 0 (File with size 0 loaded)
2353 82 common/cmd_net.c trying automatic boot
Wolfgang Denk74de7ae2009-04-01 23:34:12 +02002354 83 common/cmd_net.c running "source" command
2355 -83 common/cmd_net.c some error in automatic boot or "source" command
Heiko Schocher566a4942007-06-22 19:11:54 +02002356 84 common/cmd_net.c end without errors
wdenkc6097192002-11-03 00:24:07 +00002357
Marian Balakowicz1372cce2008-03-12 10:33:01 +01002358FIT uImage format:
2359
2360 Arg Where When
2361 100 common/cmd_bootm.c Kernel FIT Image has correct format
2362 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format
2363 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration
2364 -101 common/cmd_bootm.c Can't get configuration for kernel subimage
2365 102 common/cmd_bootm.c Kernel unit name specified
2366 -103 common/cmd_bootm.c Can't get kernel subimage node offset
Marian Balakowiczf773bea2008-03-12 10:35:46 +01002367 103 common/cmd_bootm.c Found configuration node
Marian Balakowicz1372cce2008-03-12 10:33:01 +01002368 104 common/cmd_bootm.c Got kernel subimage node offset
2369 -104 common/cmd_bootm.c Kernel subimage hash verification failed
2370 105 common/cmd_bootm.c Kernel subimage hash verification OK
2371 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture
2372 106 common/cmd_bootm.c Architecture check OK
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002373 -106 common/cmd_bootm.c Kernel subimage has wrong type
2374 107 common/cmd_bootm.c Kernel subimage type OK
Marian Balakowicz1372cce2008-03-12 10:33:01 +01002375 -107 common/cmd_bootm.c Can't get kernel subimage data/size
2376 108 common/cmd_bootm.c Got kernel subimage data/size
2377 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT)
2378 -109 common/cmd_bootm.c Can't get kernel subimage type
2379 -110 common/cmd_bootm.c Can't get kernel subimage comp
2380 -111 common/cmd_bootm.c Can't get kernel subimage os
2381 -112 common/cmd_bootm.c Can't get kernel subimage load address
2382 -113 common/cmd_bootm.c Image uncompress/copy overwrite error
2383
2384 120 common/image.c Start initial ramdisk verification
2385 -120 common/image.c Ramdisk FIT image has incorrect format
2386 121 common/image.c Ramdisk FIT image has correct format
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002387 122 common/image.c No ramdisk subimage unit name, using configuration
Marian Balakowicz1372cce2008-03-12 10:33:01 +01002388 -122 common/image.c Can't get configuration for ramdisk subimage
2389 123 common/image.c Ramdisk unit name specified
2390 -124 common/image.c Can't get ramdisk subimage node offset
2391 125 common/image.c Got ramdisk subimage node offset
2392 -125 common/image.c Ramdisk subimage hash verification failed
2393 126 common/image.c Ramdisk subimage hash verification OK
2394 -126 common/image.c Ramdisk subimage for unsupported architecture
2395 127 common/image.c Architecture check OK
2396 -127 common/image.c Can't get ramdisk subimage data/size
2397 128 common/image.c Got ramdisk subimage data/size
2398 129 common/image.c Can't get ramdisk load address
2399 -129 common/image.c Got ramdisk load address
2400
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002401 -130 common/cmd_doc.c Incorrect FIT image format
Marian Balakowicz1372cce2008-03-12 10:33:01 +01002402 131 common/cmd_doc.c FIT image format OK
2403
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002404 -140 common/cmd_ide.c Incorrect FIT image format
Marian Balakowicz1372cce2008-03-12 10:33:01 +01002405 141 common/cmd_ide.c FIT image format OK
2406
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002407 -150 common/cmd_nand.c Incorrect FIT image format
Marian Balakowicz1372cce2008-03-12 10:33:01 +01002408 151 common/cmd_nand.c FIT image format OK
2409
Wolfgang Denk4cf26092011-10-07 09:58:21 +02002410- Standalone program support:
2411 CONFIG_STANDALONE_LOAD_ADDR
2412
Wolfgang Denk6feff892011-10-09 21:06:34 +02002413 This option defines a board specific value for the
2414 address where standalone program gets loaded, thus
2415 overwriting the architecture dependent default
Wolfgang Denk4cf26092011-10-07 09:58:21 +02002416 settings.
2417
2418- Frame Buffer Address:
2419 CONFIG_FB_ADDR
2420
2421 Define CONFIG_FB_ADDR if you want to use specific
Wolfgang Denk44a53b52013-01-03 00:43:59 +00002422 address for frame buffer. This is typically the case
2423 when using a graphics controller has separate video
2424 memory. U-Boot will then place the frame buffer at
2425 the given address instead of dynamically reserving it
2426 in system RAM by calling lcd_setmem(), which grabs
2427 the memory for the frame buffer depending on the
2428 configured panel size.
Wolfgang Denk4cf26092011-10-07 09:58:21 +02002429
2430 Please see board_init_f function.
2431
Detlev Zundelcccfc2a2009-12-01 17:16:19 +01002432- Automatic software updates via TFTP server
2433 CONFIG_UPDATE_TFTP
2434 CONFIG_UPDATE_TFTP_CNT_MAX
2435 CONFIG_UPDATE_TFTP_MSEC_MAX
2436
2437 These options enable and control the auto-update feature;
2438 for a more detailed description refer to doc/README.update.
2439
2440- MTD Support (mtdparts command, UBI support)
2441 CONFIG_MTD_DEVICE
2442
2443 Adds the MTD device infrastructure from the Linux kernel.
2444 Needed for mtdparts command support.
2445
2446 CONFIG_MTD_PARTITIONS
2447
2448 Adds the MTD partitioning infrastructure from the Linux
2449 kernel. Needed for UBI support.
2450
Joe Hershberger70c219c2013-04-08 10:32:48 +00002451- UBI support
Heiko Schocherff94bc42014-06-24 10:10:04 +02002452 CONFIG_MTD_UBI_WL_THRESHOLD
2453 This parameter defines the maximum difference between the highest
2454 erase counter value and the lowest erase counter value of eraseblocks
2455 of UBI devices. When this threshold is exceeded, UBI starts performing
2456 wear leveling by means of moving data from eraseblock with low erase
2457 counter to eraseblocks with high erase counter.
2458
2459 The default value should be OK for SLC NAND flashes, NOR flashes and
2460 other flashes which have eraseblock life-cycle 100000 or more.
2461 However, in case of MLC NAND flashes which typically have eraseblock
2462 life-cycle less than 10000, the threshold should be lessened (e.g.,
2463 to 128 or 256, although it does not have to be power of 2).
2464
2465 default: 4096
Simon Glassc654b512014-10-23 18:58:54 -06002466
Heiko Schocherff94bc42014-06-24 10:10:04 +02002467 CONFIG_MTD_UBI_BEB_LIMIT
2468 This option specifies the maximum bad physical eraseblocks UBI
2469 expects on the MTD device (per 1024 eraseblocks). If the
2470 underlying flash does not admit of bad eraseblocks (e.g. NOR
2471 flash), this value is ignored.
2472
2473 NAND datasheets often specify the minimum and maximum NVM
2474 (Number of Valid Blocks) for the flashes' endurance lifetime.
2475 The maximum expected bad eraseblocks per 1024 eraseblocks
2476 then can be calculated as "1024 * (1 - MinNVB / MaxNVB)",
2477 which gives 20 for most NANDs (MaxNVB is basically the total
2478 count of eraseblocks on the chip).
2479
2480 To put it differently, if this value is 20, UBI will try to
2481 reserve about 1.9% of physical eraseblocks for bad blocks
2482 handling. And that will be 1.9% of eraseblocks on the entire
2483 NAND chip, not just the MTD partition UBI attaches. This means
2484 that if you have, say, a NAND flash chip admits maximum 40 bad
2485 eraseblocks, and it is split on two MTD partitions of the same
2486 size, UBI will reserve 40 eraseblocks when attaching a
2487 partition.
2488
2489 default: 20
2490
2491 CONFIG_MTD_UBI_FASTMAP
2492 Fastmap is a mechanism which allows attaching an UBI device
2493 in nearly constant time. Instead of scanning the whole MTD device it
2494 only has to locate a checkpoint (called fastmap) on the device.
2495 The on-flash fastmap contains all information needed to attach
2496 the device. Using fastmap makes only sense on large devices where
2497 attaching by scanning takes long. UBI will not automatically install
2498 a fastmap on old images, but you can set the UBI parameter
2499 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT to 1 if you want so. Please note
2500 that fastmap-enabled images are still usable with UBI implementations
2501 without fastmap support. On typical flash devices the whole fastmap
2502 fits into one PEB. UBI will reserve PEBs to hold two fastmaps.
2503
2504 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT
2505 Set this parameter to enable fastmap automatically on images
2506 without a fastmap.
2507 default: 0
2508
Heiko Schocher0195a7b2015-10-22 06:19:21 +02002509 CONFIG_MTD_UBI_FM_DEBUG
2510 Enable UBI fastmap debug
2511 default: 0
2512
Daniel Schwierzeck6a11cf42011-07-18 07:48:07 +00002513- SPL framework
Wolfgang Denk04e5ae72011-09-11 21:24:09 +02002514 CONFIG_SPL
2515 Enable building of SPL globally.
Daniel Schwierzeck6a11cf42011-07-18 07:48:07 +00002516
Tom Rini95579792012-02-14 07:29:40 +00002517 CONFIG_SPL_LDSCRIPT
2518 LDSCRIPT for linking the SPL binary.
2519
Albert ARIBAUD6ebc3462013-04-12 05:14:30 +00002520 CONFIG_SPL_MAX_FOOTPRINT
2521 Maximum size in memory allocated to the SPL, BSS included.
2522 When defined, the linker checks that the actual memory
2523 used by SPL from _start to __bss_end does not exceed it.
Albert ARIBAUD8960af82013-04-14 04:48:38 +00002524 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
Albert ARIBAUD6ebc3462013-04-12 05:14:30 +00002525 must not be both defined at the same time.
2526
Tom Rini95579792012-02-14 07:29:40 +00002527 CONFIG_SPL_MAX_SIZE
Albert ARIBAUD6ebc3462013-04-12 05:14:30 +00002528 Maximum size of the SPL image (text, data, rodata, and
2529 linker lists sections), BSS excluded.
2530 When defined, the linker checks that the actual size does
2531 not exceed it.
Tom Rini95579792012-02-14 07:29:40 +00002532
Wolfgang Denk04e5ae72011-09-11 21:24:09 +02002533 CONFIG_SPL_TEXT_BASE
2534 TEXT_BASE for linking the SPL binary.
Daniel Schwierzeck6a11cf42011-07-18 07:48:07 +00002535
Scott Wood94a45bb2012-09-20 19:05:12 -05002536 CONFIG_SPL_RELOC_TEXT_BASE
2537 Address to relocate to. If unspecified, this is equal to
2538 CONFIG_SPL_TEXT_BASE (i.e. no relocation is done).
2539
Tom Rini95579792012-02-14 07:29:40 +00002540 CONFIG_SPL_BSS_START_ADDR
2541 Link address for the BSS within the SPL binary.
2542
2543 CONFIG_SPL_BSS_MAX_SIZE
Albert ARIBAUD6ebc3462013-04-12 05:14:30 +00002544 Maximum size in memory allocated to the SPL BSS.
2545 When defined, the linker checks that the actual memory used
2546 by SPL from __bss_start to __bss_end does not exceed it.
Albert ARIBAUD8960af82013-04-14 04:48:38 +00002547 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
Albert ARIBAUD6ebc3462013-04-12 05:14:30 +00002548 must not be both defined at the same time.
Tom Rini95579792012-02-14 07:29:40 +00002549
2550 CONFIG_SPL_STACK
2551 Adress of the start of the stack SPL will use
2552
Albert ARIBAUD \(3ADEV\)8c80eb32015-03-31 11:40:50 +02002553 CONFIG_SPL_PANIC_ON_RAW_IMAGE
2554 When defined, SPL will panic() if the image it has
2555 loaded does not have a signature.
2556 Defining this is useful when code which loads images
2557 in SPL cannot guarantee that absolutely all read errors
2558 will be caught.
2559 An example is the LPC32XX MLC NAND driver, which will
2560 consider that a completely unreadable NAND block is bad,
2561 and thus should be skipped silently.
2562
Scott Wood94a45bb2012-09-20 19:05:12 -05002563 CONFIG_SPL_RELOC_STACK
2564 Adress of the start of the stack SPL will use after
2565 relocation. If unspecified, this is equal to
2566 CONFIG_SPL_STACK.
2567
Tom Rini95579792012-02-14 07:29:40 +00002568 CONFIG_SYS_SPL_MALLOC_START
2569 Starting address of the malloc pool used in SPL.
Fabio Estevam9ac4fc82015-11-12 12:30:19 -02002570 When this option is set the full malloc is used in SPL and
2571 it is set up by spl_init() and before that, the simple malloc()
2572 can be used if CONFIG_SYS_MALLOC_F is defined.
Tom Rini95579792012-02-14 07:29:40 +00002573
2574 CONFIG_SYS_SPL_MALLOC_SIZE
2575 The size of the malloc pool used in SPL.
Daniel Schwierzeck6a11cf42011-07-18 07:48:07 +00002576
Tom Rini9607faf2014-03-28 12:03:39 -04002577 CONFIG_SPL_OS_BOOT
2578 Enable booting directly to an OS from SPL.
2579 See also: doc/README.falcon
2580
Tom Rini861a86f2012-08-13 11:37:56 -07002581 CONFIG_SPL_DISPLAY_PRINT
2582 For ARM, enable an optional function to print more information
2583 about the running system.
2584
Scott Wood4b919722012-09-20 16:35:21 -05002585 CONFIG_SPL_INIT_MINIMAL
2586 Arch init code should be built for a very small image
2587
Paul Kocialkowskib97300b2014-11-08 23:14:56 +01002588 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_PARTITION
2589 Partition on the MMC to load U-Boot from when the MMC is being
2590 used in raw mode
2591
Peter Korsgaard2b75b0a2013-05-13 08:36:29 +00002592 CONFIG_SYS_MMCSD_RAW_MODE_KERNEL_SECTOR
2593 Sector to load kernel uImage from when MMC is being
2594 used in raw mode (for Falcon mode)
2595
2596 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTOR,
2597 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTORS
2598 Sector and number of sectors to load kernel argument
2599 parameters from when MMC is being used in raw mode
2600 (for falcon mode)
2601
Paul Kocialkowskie2ccdf82014-11-08 23:14:55 +01002602 CONFIG_SYS_MMCSD_FS_BOOT_PARTITION
2603 Partition on the MMC to load U-Boot from when the MMC is being
2604 used in fs mode
2605
Guillaume GARDETfae81c72014-10-15 17:53:13 +02002606 CONFIG_SPL_FS_LOAD_PAYLOAD_NAME
2607 Filename to read to load U-Boot when reading from filesystem
2608
2609 CONFIG_SPL_FS_LOAD_KERNEL_NAME
Peter Korsgaard7ad2cc72013-05-13 08:36:27 +00002610 Filename to read to load kernel uImage when reading
Guillaume GARDETfae81c72014-10-15 17:53:13 +02002611 from filesystem (for Falcon mode)
Peter Korsgaard7ad2cc72013-05-13 08:36:27 +00002612
Guillaume GARDETfae81c72014-10-15 17:53:13 +02002613 CONFIG_SPL_FS_LOAD_ARGS_NAME
Peter Korsgaard7ad2cc72013-05-13 08:36:27 +00002614 Filename to read to load kernel argument parameters
Guillaume GARDETfae81c72014-10-15 17:53:13 +02002615 when reading from filesystem (for Falcon mode)
Peter Korsgaard7ad2cc72013-05-13 08:36:27 +00002616
Scott Wood06f60ae2012-12-06 13:33:17 +00002617 CONFIG_SPL_MPC83XX_WAIT_FOR_NAND
2618 Set this for NAND SPL on PPC mpc83xx targets, so that
2619 start.S waits for the rest of the SPL to load before
2620 continuing (the hardware starts execution after just
2621 loading the first page rather than the full 4K).
2622
Prabhakar Kushwaha651fcf62014-04-08 19:12:31 +05302623 CONFIG_SPL_SKIP_RELOCATE
2624 Avoid SPL relocation
2625
Scott Wood6f2f01b2012-09-20 19:09:07 -05002626 CONFIG_SPL_NAND_BASE
2627 Include nand_base.c in the SPL. Requires
2628 CONFIG_SPL_NAND_DRIVERS.
2629
2630 CONFIG_SPL_NAND_DRIVERS
2631 SPL uses normal NAND drivers, not minimal drivers.
2632
2633 CONFIG_SPL_NAND_ECC
2634 Include standard software ECC in the SPL
2635
Tom Rini95579792012-02-14 07:29:40 +00002636 CONFIG_SPL_NAND_SIMPLE
Scott Wood7d4b7952012-09-21 18:35:27 -05002637 Support for NAND boot using simple NAND drivers that
2638 expose the cmd_ctrl() interface.
Tom Rini95579792012-02-14 07:29:40 +00002639
Thomas Gleixner6f4e7d32016-07-12 20:28:12 +02002640 CONFIG_SPL_UBI
2641 Support for a lightweight UBI (fastmap) scanner and
2642 loader
2643
Heiko Schocher0c3117b2014-10-31 08:31:00 +01002644 CONFIG_SPL_NAND_RAW_ONLY
2645 Support to boot only raw u-boot.bin images. Use this only
2646 if you need to save space.
2647
Ying Zhang7c8eea52013-08-16 15:16:12 +08002648 CONFIG_SPL_COMMON_INIT_DDR
2649 Set for common ddr init with serial presence detect in
2650 SPL binary.
2651
Tom Rini95579792012-02-14 07:29:40 +00002652 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT,
2653 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE,
2654 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS,
2655 CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE,
2656 CONFIG_SYS_NAND_ECCBYTES
2657 Defines the size and behavior of the NAND that SPL uses
Scott Wood7d4b7952012-09-21 18:35:27 -05002658 to read U-Boot
Tom Rini95579792012-02-14 07:29:40 +00002659
Prabhakar Kushwahafbe76ae2013-12-11 12:42:11 +05302660 CONFIG_SPL_NAND_BOOT
2661 Add support NAND boot
2662
Tom Rini95579792012-02-14 07:29:40 +00002663 CONFIG_SYS_NAND_U_BOOT_OFFS
Scott Wood7d4b7952012-09-21 18:35:27 -05002664 Location in NAND to read U-Boot from
2665
2666 CONFIG_SYS_NAND_U_BOOT_DST
2667 Location in memory to load U-Boot to
2668
2669 CONFIG_SYS_NAND_U_BOOT_SIZE
2670 Size of image to load
Tom Rini95579792012-02-14 07:29:40 +00002671
2672 CONFIG_SYS_NAND_U_BOOT_START
Scott Wood7d4b7952012-09-21 18:35:27 -05002673 Entry point in loaded image to jump to
Tom Rini95579792012-02-14 07:29:40 +00002674
2675 CONFIG_SYS_NAND_HW_ECC_OOBFIRST
2676 Define this if you need to first read the OOB and then the
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08002677 data. This is used, for example, on davinci platforms.
Tom Rini95579792012-02-14 07:29:40 +00002678
Pavel Machekc57b9532012-08-30 22:42:11 +02002679 CONFIG_SPL_RAM_DEVICE
2680 Support for running image already present in ram, in SPL binary
2681
Scott Wood74752ba2012-12-06 13:33:16 +00002682 CONFIG_SPL_PAD_TO
Benoît Thébaudeau6113d3f2013-04-11 09:35:49 +00002683 Image offset to which the SPL should be padded before appending
2684 the SPL payload. By default, this is defined as
2685 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
2686 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
2687 payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
Scott Wood74752ba2012-12-06 13:33:16 +00002688
Scott Woodca2fca22012-09-21 16:27:32 -05002689 CONFIG_SPL_TARGET
2690 Final target image containing SPL and payload. Some SPLs
2691 use an arch-specific makefile fragment instead, for
2692 example if more than one image needs to be produced.
2693
Marek Vasutb527b9c2018-05-13 00:22:52 +02002694 CONFIG_SPL_FIT_PRINT
Simon Glass87ebee32013-05-08 08:05:59 +00002695 Printing information about a FIT image adds quite a bit of
2696 code to SPL. So this is normally disabled in SPL. Use this
2697 option to re-enable it. This will affect the output of the
2698 bootm command when booting a FIT image.
2699
Ying Zhang3aa29de2013-08-16 15:16:15 +08002700- TPL framework
2701 CONFIG_TPL
2702 Enable building of TPL globally.
2703
2704 CONFIG_TPL_PAD_TO
2705 Image offset to which the TPL should be padded before appending
2706 the TPL payload. By default, this is defined as
Wolfgang Denk93e14592013-10-04 17:43:24 +02002707 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
2708 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
2709 payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
Ying Zhang3aa29de2013-08-16 15:16:15 +08002710
wdenka8c7c702003-12-06 19:49:23 +00002711- Interrupt support (PPC):
2712
wdenkd4ca31c2004-01-02 14:00:00 +00002713 There are common interrupt_init() and timer_interrupt()
2714 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002715 for CPU specific initialization. interrupt_init_cpu()
wdenkd4ca31c2004-01-02 14:00:00 +00002716 should set decrementer_count to appropriate value. If
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002717 CPU resets decrementer automatically after interrupt
wdenkd4ca31c2004-01-02 14:00:00 +00002718 (ppc4xx) it should set decrementer_count to zero.
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002719 timer_interrupt() calls timer_interrupt_cpu() for CPU
wdenkd4ca31c2004-01-02 14:00:00 +00002720 specific handling. If board has watchdog / status_led
2721 / other_activity_monitor it works automatically from
2722 general timer_interrupt().
wdenka8c7c702003-12-06 19:49:23 +00002723
wdenkc6097192002-11-03 00:24:07 +00002724
Helmut Raiger9660e442011-10-20 04:19:47 +00002725Board initialization settings:
2726------------------------------
2727
2728During Initialization u-boot calls a number of board specific functions
2729to allow the preparation of board specific prerequisites, e.g. pin setup
2730before drivers are initialized. To enable these callbacks the
2731following configuration macros have to be defined. Currently this is
2732architecture specific, so please check arch/your_architecture/lib/board.c
2733typically in board_init_f() and board_init_r().
2734
2735- CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f()
2736- CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r()
2737- CONFIG_BOARD_LATE_INIT: Call board_late_init()
2738- CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init()
wdenkc6097192002-11-03 00:24:07 +00002739
wdenkc6097192002-11-03 00:24:07 +00002740Configuration Settings:
2741-----------------------
2742
York Sun4d1fd7f2014-02-26 17:03:19 -08002743- CONFIG_SYS_SUPPORT_64BIT_DATA: Defined automatically if compiled as 64-bit.
2744 Optionally it can be defined to support 64-bit memory commands.
2745
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002746- CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
wdenkc6097192002-11-03 00:24:07 +00002747 undefine this when you're short of memory.
2748
Peter Tyser2fb26042009-01-27 18:03:12 -06002749- CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
2750 width of the commands listed in the 'help' command output.
2751
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002752- CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to
wdenkc6097192002-11-03 00:24:07 +00002753 prompt for user input.
2754
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002755- CONFIG_SYS_CBSIZE: Buffer size for input from the Console
wdenkc6097192002-11-03 00:24:07 +00002756
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002757- CONFIG_SYS_PBSIZE: Buffer size for Console output
wdenkc6097192002-11-03 00:24:07 +00002758
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002759- CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands
wdenkc6097192002-11-03 00:24:07 +00002760
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002761- CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to
wdenkc6097192002-11-03 00:24:07 +00002762 the application (usually a Linux kernel) when it is
2763 booted
2764
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002765- CONFIG_SYS_BAUDRATE_TABLE:
wdenkc6097192002-11-03 00:24:07 +00002766 List of legal baudrate settings for this board.
2767
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002768- CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END:
wdenkc6097192002-11-03 00:24:07 +00002769 Begin and End addresses of the area used by the
2770 simple memory test.
2771
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002772- CONFIG_SYS_MEMTEST_SCRATCH:
wdenk5f535fe2003-09-18 09:21:33 +00002773 Scratch address used by the alternate memory test
2774 You only need to set this if address zero isn't writeable
2775
York Sune8149522015-12-04 11:57:07 -08002776- CONFIG_SYS_MEM_RESERVE_SECURE
York Sune61a7532016-06-24 16:46:18 -07002777 Only implemented for ARMv8 for now.
York Sune8149522015-12-04 11:57:07 -08002778 If defined, the size of CONFIG_SYS_MEM_RESERVE_SECURE memory
2779 is substracted from total RAM and won't be reported to OS.
2780 This memory can be used as secure memory. A variable
York Sune61a7532016-06-24 16:46:18 -07002781 gd->arch.secure_ram is used to track the location. In systems
York Sune8149522015-12-04 11:57:07 -08002782 the RAM base is not zero, or RAM is divided into banks,
2783 this variable needs to be recalcuated to get the address.
2784
York Sunaabd7dd2015-12-07 11:05:29 -08002785- CONFIG_SYS_MEM_TOP_HIDE:
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002786 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header,
Stefan Roese14f73ca2008-03-26 10:14:11 +01002787 this specified memory area will get subtracted from the top
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002788 (end) of RAM and won't get "touched" at all by U-Boot. By
Stefan Roese14f73ca2008-03-26 10:14:11 +01002789 fixing up gd->ram_size the Linux kernel should gets passed
2790 the now "corrected" memory size and won't touch it either.
2791 This should work for arch/ppc and arch/powerpc. Only Linux
Stefan Roese5e12e752008-03-28 11:02:53 +01002792 board ports in arch/powerpc with bootwrapper support that
Stefan Roese14f73ca2008-03-26 10:14:11 +01002793 recalculate the memory size from the SDRAM controller setup
Stefan Roese5e12e752008-03-28 11:02:53 +01002794 will have to get fixed in Linux additionally.
Stefan Roese14f73ca2008-03-26 10:14:11 +01002795
2796 This option can be used as a workaround for the 440EPx/GRx
2797 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't
2798 be touched.
2799
2800 WARNING: Please make sure that this value is a multiple of
2801 the Linux page size (normally 4k). If this is not the case,
2802 then the end address of the Linux memory will be located at a
2803 non page size aligned address and this could cause major
2804 problems.
2805
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002806- CONFIG_SYS_LOADS_BAUD_CHANGE:
wdenkc6097192002-11-03 00:24:07 +00002807 Enable temporary baudrate change while serial download
2808
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002809- CONFIG_SYS_SDRAM_BASE:
wdenkc6097192002-11-03 00:24:07 +00002810 Physical start address of SDRAM. _Must_ be 0 here.
2811
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002812- CONFIG_SYS_FLASH_BASE:
wdenkc6097192002-11-03 00:24:07 +00002813 Physical start address of Flash memory.
2814
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002815- CONFIG_SYS_MONITOR_BASE:
wdenkc6097192002-11-03 00:24:07 +00002816 Physical start address of boot monitor code (set by
2817 make config files to be same as the text base address
Wolfgang Denk14d0a022010-10-07 21:51:12 +02002818 (CONFIG_SYS_TEXT_BASE) used when linking) - same as
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002819 CONFIG_SYS_FLASH_BASE when booting from flash.
wdenkc6097192002-11-03 00:24:07 +00002820
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002821- CONFIG_SYS_MONITOR_LEN:
wdenk8bde7f72003-06-27 21:31:46 +00002822 Size of memory reserved for monitor code, used to
2823 determine _at_compile_time_ (!) if the environment is
2824 embedded within the U-Boot image, or in a separate
2825 flash sector.
wdenkc6097192002-11-03 00:24:07 +00002826
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002827- CONFIG_SYS_MALLOC_LEN:
wdenkc6097192002-11-03 00:24:07 +00002828 Size of DRAM reserved for malloc() use.
2829
Simon Glassd59476b2014-07-10 22:23:28 -06002830- CONFIG_SYS_MALLOC_F_LEN
2831 Size of the malloc() pool for use before relocation. If
2832 this is defined, then a very simple malloc() implementation
2833 will become available before relocation. The address is just
2834 below the global data, and the stack is moved down to make
2835 space.
2836
2837 This feature allocates regions with increasing addresses
2838 within the region. calloc() is supported, but realloc()
2839 is not available. free() is supported but does nothing.
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08002840 The memory will be freed (or in fact just forgotten) when
Simon Glassd59476b2014-07-10 22:23:28 -06002841 U-Boot relocates itself.
2842
Simon Glass38687ae2014-11-10 17:16:54 -07002843- CONFIG_SYS_MALLOC_SIMPLE
2844 Provides a simple and small malloc() and calloc() for those
2845 boards which do not use the full malloc in SPL (which is
2846 enabled with CONFIG_SYS_SPL_MALLOC_START).
2847
Thierry Reding1dfdd9b2014-12-09 22:25:22 -07002848- CONFIG_SYS_NONCACHED_MEMORY:
2849 Size of non-cached memory area. This area of memory will be
2850 typically located right below the malloc() area and mapped
2851 uncached in the MMU. This is useful for drivers that would
2852 otherwise require a lot of explicit cache maintenance. For
2853 some drivers it's also impossible to properly maintain the
2854 cache. For example if the regions that need to be flushed
2855 are not a multiple of the cache-line size, *and* padding
2856 cannot be allocated between the regions to align them (i.e.
2857 if the HW requires a contiguous array of regions, and the
2858 size of each region is not cache-aligned), then a flush of
2859 one region may result in overwriting data that hardware has
2860 written to another region in the same cache-line. This can
2861 happen for example in network drivers where descriptors for
2862 buffers are typically smaller than the CPU cache-line (e.g.
2863 16 bytes vs. 32 or 64 bytes).
2864
2865 Non-cached memory is only supported on 32-bit ARM at present.
2866
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002867- CONFIG_SYS_BOOTM_LEN:
Stefan Roese15940c92006-03-13 11:16:36 +01002868 Normally compressed uImages are limited to an
2869 uncompressed size of 8 MBytes. If this is not enough,
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002870 you can define CONFIG_SYS_BOOTM_LEN in your board config file
Stefan Roese15940c92006-03-13 11:16:36 +01002871 to adjust this setting to your needs.
2872
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002873- CONFIG_SYS_BOOTMAPSZ:
wdenkc6097192002-11-03 00:24:07 +00002874 Maximum size of memory mapped by the startup code of
2875 the Linux kernel; all data that must be processed by
Bartlomiej Sieka7d721e32008-04-14 15:44:16 +02002876 the Linux kernel (bd_info, boot arguments, FDT blob if
2877 used) must be put below this limit, unless "bootm_low"
Robert P. J. Day1bce2ae2013-09-16 07:15:45 -04002878 environment variable is defined and non-zero. In such case
Bartlomiej Sieka7d721e32008-04-14 15:44:16 +02002879 all data for the Linux kernel must be between "bootm_low"
Wolfgang Denkc0f40852011-10-26 10:21:21 +00002880 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment
Grant Likelyc3624e62011-03-28 09:58:43 +00002881 variable "bootm_mapsize" will override the value of
2882 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined,
2883 then the value in "bootm_size" will be used instead.
wdenkc6097192002-11-03 00:24:07 +00002884
John Rigbyfca43cc2010-10-13 13:57:35 -06002885- CONFIG_SYS_BOOT_RAMDISK_HIGH:
2886 Enable initrd_high functionality. If defined then the
2887 initrd_high feature is enabled and the bootm ramdisk subcommand
2888 is enabled.
2889
2890- CONFIG_SYS_BOOT_GET_CMDLINE:
2891 Enables allocating and saving kernel cmdline in space between
2892 "bootm_low" and "bootm_low" + BOOTMAPSZ.
2893
2894- CONFIG_SYS_BOOT_GET_KBD:
2895 Enables allocating and saving a kernel copy of the bd_info in
2896 space between "bootm_low" and "bootm_low" + BOOTMAPSZ.
2897
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002898- CONFIG_SYS_MAX_FLASH_BANKS:
wdenkc6097192002-11-03 00:24:07 +00002899 Max number of Flash memory banks
2900
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002901- CONFIG_SYS_MAX_FLASH_SECT:
wdenkc6097192002-11-03 00:24:07 +00002902 Max number of sectors on a Flash chip
2903
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002904- CONFIG_SYS_FLASH_ERASE_TOUT:
wdenkc6097192002-11-03 00:24:07 +00002905 Timeout for Flash erase operations (in ms)
2906
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002907- CONFIG_SYS_FLASH_WRITE_TOUT:
wdenkc6097192002-11-03 00:24:07 +00002908 Timeout for Flash write operations (in ms)
2909
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002910- CONFIG_SYS_FLASH_LOCK_TOUT
wdenk8564acf2003-07-14 22:13:32 +00002911 Timeout for Flash set sector lock bit operation (in ms)
2912
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002913- CONFIG_SYS_FLASH_UNLOCK_TOUT
wdenk8564acf2003-07-14 22:13:32 +00002914 Timeout for Flash clear lock bits operation (in ms)
2915
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002916- CONFIG_SYS_FLASH_PROTECTION
wdenk8564acf2003-07-14 22:13:32 +00002917 If defined, hardware flash sectors protection is used
2918 instead of U-Boot software protection.
2919
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002920- CONFIG_SYS_DIRECT_FLASH_TFTP:
wdenkc6097192002-11-03 00:24:07 +00002921
2922 Enable TFTP transfers directly to flash memory;
2923 without this option such a download has to be
2924 performed in two steps: (1) download to RAM, and (2)
2925 copy from RAM to flash.
2926
2927 The two-step approach is usually more reliable, since
2928 you can check if the download worked before you erase
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002929 the flash, but in some situations (when system RAM is
2930 too limited to allow for a temporary copy of the
wdenkc6097192002-11-03 00:24:07 +00002931 downloaded image) this option may be very useful.
2932
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002933- CONFIG_SYS_FLASH_CFI:
wdenk43d96162003-03-06 00:02:04 +00002934 Define if the flash driver uses extra elements in the
wdenk5653fc32004-02-08 22:55:38 +00002935 common flash structure for storing flash geometry.
2936
Jean-Christophe PLAGNIOL-VILLARD00b18832008-08-13 01:40:42 +02002937- CONFIG_FLASH_CFI_DRIVER
wdenk5653fc32004-02-08 22:55:38 +00002938 This option also enables the building of the cfi_flash driver
2939 in the drivers directory
wdenkc6097192002-11-03 00:24:07 +00002940
Piotr Ziecik91809ed2008-11-17 15:57:58 +01002941- CONFIG_FLASH_CFI_MTD
2942 This option enables the building of the cfi_mtd driver
2943 in the drivers directory. The driver exports CFI flash
2944 to the MTD layer.
2945
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002946- CONFIG_SYS_FLASH_USE_BUFFER_WRITE
Guennadi Liakhovetski96ef8312008-04-03 13:36:02 +02002947 Use buffered writes to flash.
2948
2949- CONFIG_FLASH_SPANSION_S29WS_N
2950 s29ws-n MirrorBit flash has non-standard addresses for buffered
2951 write commands.
2952
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002953- CONFIG_SYS_FLASH_QUIET_TEST
Stefan Roese5568e612005-11-22 13:20:42 +01002954 If this option is defined, the common CFI flash doesn't
2955 print it's warning upon not recognized FLASH banks. This
2956 is useful, if some of the configured banks are only
2957 optionally available.
2958
Jerry Van Baren9a042e92008-03-08 13:48:01 -05002959- CONFIG_FLASH_SHOW_PROGRESS
2960 If defined (must be an integer), print out countdown
2961 digits and dots. Recommended value: 45 (9..1) for 80
2962 column displays, 15 (3..1) for 40 column displays.
2963
Stefan Roese352ef3f2013-04-04 15:53:14 +02002964- CONFIG_FLASH_VERIFY
2965 If defined, the content of the flash (destination) is compared
2966 against the source after the write operation. An error message
2967 will be printed when the contents are not identical.
2968 Please note that this option is useless in nearly all cases,
2969 since such flash programming errors usually are detected earlier
2970 while unprotecting/erasing/programming. Please only enable
2971 this option if you really know what you are doing.
2972
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002973- CONFIG_SYS_RX_ETH_BUFFER:
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002974 Defines the number of Ethernet receive buffers. On some
2975 Ethernet controllers it is recommended to set this value
stroese53cf9432003-06-05 15:39:44 +00002976 to 8 or even higher (EEPRO100 or 405 EMAC), since all
2977 buffers can be full shortly after enabling the interface
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002978 on high Ethernet traffic.
stroese53cf9432003-06-05 15:39:44 +00002979 Defaults to 4 if not defined.
2980
Wolfgang Denkea882ba2010-06-20 23:33:59 +02002981- CONFIG_ENV_MAX_ENTRIES
2982
Wolfgang Denk071bc922010-10-27 22:48:30 +02002983 Maximum number of entries in the hash table that is used
2984 internally to store the environment settings. The default
2985 setting is supposed to be generous and should work in most
2986 cases. This setting can be used to tune behaviour; see
2987 lib/hashtable.c for details.
Wolfgang Denkea882ba2010-06-20 23:33:59 +02002988
Joe Hershberger25980902012-12-11 22:16:31 -06002989- CONFIG_ENV_FLAGS_LIST_DEFAULT
2990- CONFIG_ENV_FLAGS_LIST_STATIC
Robert P. J. Day1bce2ae2013-09-16 07:15:45 -04002991 Enable validation of the values given to environment variables when
Joe Hershberger25980902012-12-11 22:16:31 -06002992 calling env set. Variables can be restricted to only decimal,
2993 hexadecimal, or boolean. If CONFIG_CMD_NET is also defined,
2994 the variables can also be restricted to IP address or MAC address.
2995
2996 The format of the list is:
2997 type_attribute = [s|d|x|b|i|m]
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08002998 access_attribute = [a|r|o|c]
2999 attributes = type_attribute[access_attribute]
Joe Hershberger25980902012-12-11 22:16:31 -06003000 entry = variable_name[:attributes]
3001 list = entry[,list]
3002
3003 The type attributes are:
3004 s - String (default)
3005 d - Decimal
3006 x - Hexadecimal
3007 b - Boolean ([1yYtT|0nNfF])
3008 i - IP address
3009 m - MAC address
3010
Joe Hershberger267541f2012-12-11 22:16:34 -06003011 The access attributes are:
3012 a - Any (default)
3013 r - Read-only
3014 o - Write-once
3015 c - Change-default
3016
Joe Hershberger25980902012-12-11 22:16:31 -06003017 - CONFIG_ENV_FLAGS_LIST_DEFAULT
3018 Define this to a list (string) to define the ".flags"
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08003019 environment variable in the default or embedded environment.
Joe Hershberger25980902012-12-11 22:16:31 -06003020
3021 - CONFIG_ENV_FLAGS_LIST_STATIC
3022 Define this to a list (string) to define validation that
3023 should be done if an entry is not found in the ".flags"
3024 environment variable. To override a setting in the static
3025 list, simply add an entry for the same variable name to the
3026 ".flags" variable.
3027
Joe Hershbergerbdf1fe42015-05-20 14:27:20 -05003028 If CONFIG_REGEX is defined, the variable_name above is evaluated as a
3029 regular expression. This allows multiple variables to define the same
3030 flags without explicitly listing them for each variable.
3031
Joe Hershberger267541f2012-12-11 22:16:34 -06003032- CONFIG_ENV_ACCESS_IGNORE_FORCE
3033 If defined, don't allow the -f switch to env set override variable
3034 access flags.
3035
Gabe Black0d296cc2014-10-15 04:38:30 -06003036- CONFIG_USE_STDINT
3037 If stdint.h is available with your toolchain you can define this
3038 option to enable it. You can provide option 'USE_STDINT=1' when
3039 building U-Boot to enable this.
3040
wdenkc6097192002-11-03 00:24:07 +00003041The following definitions that deal with the placement and management
3042of environment data (variable area); in general, we support the
3043following configurations:
3044
Mike Frysingerc3eb3fe2011-07-08 10:44:25 +00003045- CONFIG_BUILD_ENVCRC:
3046
3047 Builds up envcrc with the target environment so that external utils
3048 may easily extract it and embed it in final U-Boot images.
3049
wdenkc6097192002-11-03 00:24:07 +00003050BE CAREFUL! The first access to the environment happens quite early
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08003051in U-Boot initialization (when we try to get the setting of for the
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02003052console baudrate). You *MUST* have mapped your NVRAM area then, or
wdenkc6097192002-11-03 00:24:07 +00003053U-Boot will hang.
3054
3055Please note that even with NVRAM we still use a copy of the
3056environment in RAM: we could work on NVRAM directly, but we want to
3057keep settings there always unmodified except somebody uses "saveenv"
3058to save the current settings.
3059
Liu Gang0a85a9e2012-03-08 00:33:20 +00003060BE CAREFUL! For some special cases, the local device can not use
3061"saveenv" command. For example, the local device will get the
Liu Gangfc54c7f2012-08-09 05:10:01 +00003062environment stored in a remote NOR flash by SRIO or PCIE link,
3063but it can not erase, write this NOR flash by SRIO or PCIE interface.
Liu Gang0a85a9e2012-03-08 00:33:20 +00003064
Guennadi Liakhovetskib74ab732009-05-18 16:07:22 +02003065- CONFIG_NAND_ENV_DST
3066
3067 Defines address in RAM to which the nand_spl code should copy the
3068 environment. If redundant environment is used, it will be copied to
3069 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE.
3070
Bruce Adlere881cb52007-11-02 13:15:42 -07003071Please note that the environment is read-only until the monitor
wdenkc6097192002-11-03 00:24:07 +00003072has been relocated to RAM and a RAM copy of the environment has been
Simon Glass00caae62017-08-03 12:22:12 -06003073created; also, when using EEPROM you will have to use env_get_f()
wdenkc6097192002-11-03 00:24:07 +00003074until then to read environment variables.
3075
wdenk85ec0bc2003-03-31 16:34:49 +00003076The environment is protected by a CRC32 checksum. Before the monitor
3077is relocated into RAM, as a result of a bad CRC you will be working
3078with the compiled-in default environment - *silently*!!! [This is
3079necessary, because the first environment variable we need is the
3080"baudrate" setting for the console - if we have a bad CRC, we don't
3081have any device yet where we could complain.]
wdenkc6097192002-11-03 00:24:07 +00003082
3083Note: once the monitor has been relocated, then it will complain if
3084the default environment is used; a new CRC is computed as soon as you
wdenk85ec0bc2003-03-31 16:34:49 +00003085use the "saveenv" command to store a valid environment.
wdenkc6097192002-11-03 00:24:07 +00003086
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003087- CONFIG_SYS_FAULT_ECHO_LINK_DOWN:
wdenk42d1f032003-10-15 23:53:47 +00003088 Echo the inverted Ethernet link state to the fault LED.
wdenkfc3e2162003-10-08 22:33:00 +00003089
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003090 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR
wdenkfc3e2162003-10-08 22:33:00 +00003091 also needs to be defined.
3092
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003093- CONFIG_SYS_FAULT_MII_ADDR:
wdenk42d1f032003-10-15 23:53:47 +00003094 MII address of the PHY to check for the Ethernet link state.
wdenkc6097192002-11-03 00:24:07 +00003095
Ron Madridf5675aa2009-02-18 14:30:44 -08003096- CONFIG_NS16550_MIN_FUNCTIONS:
3097 Define this if you desire to only have use of the NS16550_init
3098 and NS16550_putc functions for the serial driver located at
3099 drivers/serial/ns16550.c. This option is useful for saving
3100 space for already greatly restricted images, including but not
3101 limited to NAND_SPL configurations.
3102
Simon Glassb2b92f52012-11-30 13:01:18 +00003103- CONFIG_DISPLAY_BOARDINFO
3104 Display information about the board that U-Boot is running on
3105 when U-Boot starts up. The board function checkboard() is called
3106 to do this.
3107
Simon Glasse2e3e2b2012-11-30 13:01:19 +00003108- CONFIG_DISPLAY_BOARDINFO_LATE
3109 Similar to the previous option, but display this information
3110 later, once stdio is running and output goes to the LCD, if
3111 present.
3112
Sascha Silbefeb85802013-08-11 16:40:43 +02003113- CONFIG_BOARD_SIZE_LIMIT:
3114 Maximum size of the U-Boot image. When defined, the
3115 build system checks that the actual size does not
3116 exceed it.
3117
wdenkc6097192002-11-03 00:24:07 +00003118Low Level (hardware related) configuration options:
wdenkdc7c9a12003-03-26 06:55:25 +00003119---------------------------------------------------
wdenkc6097192002-11-03 00:24:07 +00003120
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003121- CONFIG_SYS_CACHELINE_SIZE:
wdenkc6097192002-11-03 00:24:07 +00003122 Cache Line Size of the CPU.
3123
Timur Tabie46fedf2011-08-04 18:03:41 -05003124- CONFIG_SYS_CCSRBAR_DEFAULT:
3125 Default (power-on reset) physical address of CCSR on Freescale
3126 PowerPC SOCs.
3127
3128- CONFIG_SYS_CCSRBAR:
3129 Virtual address of CCSR. On a 32-bit build, this is typically
3130 the same value as CONFIG_SYS_CCSRBAR_DEFAULT.
3131
Timur Tabie46fedf2011-08-04 18:03:41 -05003132- CONFIG_SYS_CCSRBAR_PHYS:
3133 Physical address of CCSR. CCSR can be relocated to a new
3134 physical address, if desired. In this case, this macro should
Wolfgang Denkc0f40852011-10-26 10:21:21 +00003135 be set to that address. Otherwise, it should be set to the
Timur Tabie46fedf2011-08-04 18:03:41 -05003136 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR
3137 is typically relocated on 36-bit builds. It is recommended
3138 that this macro be defined via the _HIGH and _LOW macros:
3139
3140 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH
3141 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW)
3142
3143- CONFIG_SYS_CCSRBAR_PHYS_HIGH:
Wolfgang Denk4cf26092011-10-07 09:58:21 +02003144 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically
3145 either 0 (32-bit build) or 0xF (36-bit build). This macro is
Timur Tabie46fedf2011-08-04 18:03:41 -05003146 used in assembly code, so it must not contain typecasts or
3147 integer size suffixes (e.g. "ULL").
3148
3149- CONFIG_SYS_CCSRBAR_PHYS_LOW:
3150 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is
3151 used in assembly code, so it must not contain typecasts or
3152 integer size suffixes (e.g. "ULL").
3153
3154- CONFIG_SYS_CCSR_DO_NOT_RELOCATE:
3155 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be
3156 forced to a value that ensures that CCSR is not relocated.
3157
wdenk7f6c2cb2002-11-10 22:06:23 +00003158- Floppy Disk Support:
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003159 CONFIG_SYS_FDC_DRIVE_NUMBER
wdenk7f6c2cb2002-11-10 22:06:23 +00003160
3161 the default drive number (default value 0)
3162
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003163 CONFIG_SYS_ISA_IO_STRIDE
wdenk7f6c2cb2002-11-10 22:06:23 +00003164
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02003165 defines the spacing between FDC chipset registers
wdenk7f6c2cb2002-11-10 22:06:23 +00003166 (default value 1)
3167
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003168 CONFIG_SYS_ISA_IO_OFFSET
wdenk7f6c2cb2002-11-10 22:06:23 +00003169
wdenk43d96162003-03-06 00:02:04 +00003170 defines the offset of register from address. It
3171 depends on which part of the data bus is connected to
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02003172 the FDC chipset. (default value 0)
wdenk7f6c2cb2002-11-10 22:06:23 +00003173
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003174 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and
3175 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their
wdenk43d96162003-03-06 00:02:04 +00003176 default value.
wdenk7f6c2cb2002-11-10 22:06:23 +00003177
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003178 if CONFIG_SYS_FDC_HW_INIT is defined, then the function
wdenk43d96162003-03-06 00:02:04 +00003179 fdc_hw_init() is called at the beginning of the FDC
3180 setup. fdc_hw_init() must be provided by the board
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08003181 source code. It is used to make hardware-dependent
wdenk43d96162003-03-06 00:02:04 +00003182 initializations.
wdenk7f6c2cb2002-11-10 22:06:23 +00003183
Macpaul Lin0abddf82011-04-11 20:45:32 +00003184- CONFIG_IDE_AHB:
3185 Most IDE controllers were designed to be connected with PCI
3186 interface. Only few of them were designed for AHB interface.
3187 When software is doing ATA command and data transfer to
3188 IDE devices through IDE-AHB controller, some additional
3189 registers accessing to these kind of IDE-AHB controller
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08003190 is required.
Macpaul Lin0abddf82011-04-11 20:45:32 +00003191
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003192- CONFIG_SYS_IMMR: Physical address of the Internal Memory.
wdenkefe2a4d2004-12-16 21:44:03 +00003193 DO NOT CHANGE unless you know exactly what you're
Christophe Leroy907208c2017-07-06 10:23:22 +02003194 doing! (11-4) [MPC8xx systems only]
wdenkc6097192002-11-03 00:24:07 +00003195
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003196- CONFIG_SYS_INIT_RAM_ADDR:
wdenkc6097192002-11-03 00:24:07 +00003197
wdenk7152b1d2003-09-05 23:19:14 +00003198 Start address of memory area that can be used for
wdenkc6097192002-11-03 00:24:07 +00003199 initial data and stack; please note that this must be
3200 writable memory that is working WITHOUT special
3201 initialization, i. e. you CANNOT use normal RAM which
3202 will become available only after programming the
3203 memory controller and running certain initialization
3204 sequences.
3205
3206 U-Boot uses the following memory types:
Christophe Leroy907208c2017-07-06 10:23:22 +02003207 - MPC8xx: IMMR (internal memory of the CPU)
wdenkc6097192002-11-03 00:24:07 +00003208
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003209- CONFIG_SYS_GBL_DATA_OFFSET:
wdenkc6097192002-11-03 00:24:07 +00003210
3211 Offset of the initial data structure in the memory
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003212 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually
3213 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial
wdenkc6097192002-11-03 00:24:07 +00003214 data is located at the end of the available space
Wolfgang Denk553f0982010-10-26 13:32:32 +02003215 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE -
Simon Glassacd51f92016-10-02 18:01:06 -06003216 GENERATED_GBL_DATA_SIZE), and the initial stack is just
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003217 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR +
3218 CONFIG_SYS_GBL_DATA_OFFSET) downward.
wdenkc6097192002-11-03 00:24:07 +00003219
3220 Note:
3221 On the MPC824X (or other systems that use the data
3222 cache for initial memory) the address chosen for
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003223 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must
wdenkc6097192002-11-03 00:24:07 +00003224 point to an otherwise UNUSED address space between
3225 the top of RAM and the start of the PCI space.
3226
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003227- CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27)
wdenkc6097192002-11-03 00:24:07 +00003228
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003229- CONFIG_SYS_OR_TIMING_SDRAM:
wdenkc6097192002-11-03 00:24:07 +00003230 SDRAM timing
3231
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003232- CONFIG_SYS_MAMR_PTA:
wdenkc6097192002-11-03 00:24:07 +00003233 periodic timer for refresh
3234
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003235- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM,
3236 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP,
3237 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM,
3238 CONFIG_SYS_BR1_PRELIM:
wdenkc6097192002-11-03 00:24:07 +00003239 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
3240
3241- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003242 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM,
3243 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM:
wdenkc6097192002-11-03 00:24:07 +00003244 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
3245
Andrew Sharp69fd2d32012-08-29 14:16:32 +00003246- CONFIG_PCI_ENUM_ONLY
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08003247 Only scan through and get the devices on the buses.
Andrew Sharp69fd2d32012-08-29 14:16:32 +00003248 Don't do any setup work, presumably because someone or
3249 something has already done it, and we don't need to do it
3250 a second time. Useful for platforms that are pre-booted
3251 by coreboot or similar.
3252
Gabor Juhos842033e2013-05-30 07:06:12 +00003253- CONFIG_PCI_INDIRECT_BRIDGE:
3254 Enable support for indirect PCI bridges.
3255
Kumar Galaa09b9b62010-12-30 12:09:53 -06003256- CONFIG_SYS_SRIO:
3257 Chip has SRIO or not
3258
3259- CONFIG_SRIO1:
3260 Board has SRIO 1 port available
3261
3262- CONFIG_SRIO2:
3263 Board has SRIO 2 port available
3264
Liu Gangc8b28152013-05-07 16:30:46 +08003265- CONFIG_SRIO_PCIE_BOOT_MASTER
3266 Board can support master function for Boot from SRIO and PCIE
3267
Kumar Galaa09b9b62010-12-30 12:09:53 -06003268- CONFIG_SYS_SRIOn_MEM_VIRT:
3269 Virtual Address of SRIO port 'n' memory region
3270
3271- CONFIG_SYS_SRIOn_MEM_PHYS:
3272 Physical Address of SRIO port 'n' memory region
3273
3274- CONFIG_SYS_SRIOn_MEM_SIZE:
3275 Size of SRIO port 'n' memory region
3276
Fabio Estevam66bd1842013-04-11 09:35:34 +00003277- CONFIG_SYS_NAND_BUSWIDTH_16BIT
3278 Defined to tell the NAND controller that the NAND chip is using
3279 a 16 bit bus.
3280 Not all NAND drivers use this symbol.
Fabio Estevama430e912013-04-11 09:35:35 +00003281 Example of drivers that use it:
Fabio Estevam66bd1842013-04-11 09:35:34 +00003282 - drivers/mtd/nand/ndfc.c
Fabio Estevama430e912013-04-11 09:35:35 +00003283 - drivers/mtd/nand/mxc_nand.c
Alex Watermaneced4622011-05-19 15:08:36 -04003284
3285- CONFIG_SYS_NDFC_EBC0_CFG
3286 Sets the EBC0_CFG register for the NDFC. If not defined
3287 a default value will be used.
3288
Ben Warrenbb99ad62006-09-07 16:50:54 -04003289- CONFIG_SPD_EEPROM
Wolfgang Denk218ca722008-03-26 10:40:12 +01003290 Get DDR timing information from an I2C EEPROM. Common
3291 with pluggable memory modules such as SODIMMs
3292
Ben Warrenbb99ad62006-09-07 16:50:54 -04003293 SPD_EEPROM_ADDRESS
3294 I2C address of the SPD EEPROM
3295
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003296- CONFIG_SYS_SPD_BUS_NUM
Wolfgang Denk218ca722008-03-26 10:40:12 +01003297 If SPD EEPROM is on an I2C bus other than the first
3298 one, specify here. Note that the value must resolve
3299 to something your driver can deal with.
Ben Warrenbb99ad62006-09-07 16:50:54 -04003300
York Sun1b3e3c42011-06-07 09:42:16 +08003301- CONFIG_SYS_DDR_RAW_TIMING
3302 Get DDR timing information from other than SPD. Common with
3303 soldered DDR chips onboard without SPD. DDR raw timing
3304 parameters are extracted from datasheet and hard-coded into
3305 header files or board specific files.
3306
York Sun6f5e1dc2011-09-16 13:21:35 -07003307- CONFIG_FSL_DDR_INTERACTIVE
3308 Enable interactive DDR debugging. See doc/README.fsl-ddr.
3309
York Sune32d59a2015-01-06 13:18:55 -08003310- CONFIG_FSL_DDR_SYNC_REFRESH
3311 Enable sync of refresh for multiple controllers.
3312
York Sun4516ff82015-03-19 09:30:28 -07003313- CONFIG_FSL_DDR_BIST
3314 Enable built-in memory test for Freescale DDR controllers.
3315
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003316- CONFIG_SYS_83XX_DDR_USES_CS0
Wolfgang Denk218ca722008-03-26 10:40:12 +01003317 Only for 83xx systems. If specified, then DDR should
3318 be configured using CS0 and CS1 instead of CS2 and CS3.
Timur Tabi2ad6b512006-10-31 18:44:42 -06003319
wdenkc26e4542004-04-18 10:13:26 +00003320- CONFIG_RMII
3321 Enable RMII mode for all FECs.
3322 Note that this is a global option, we can't
3323 have one FEC in standard MII mode and another in RMII mode.
3324
wdenk5cf91d62004-04-23 20:32:05 +00003325- CONFIG_CRC32_VERIFY
3326 Add a verify option to the crc32 command.
3327 The syntax is:
3328
3329 => crc32 -v <address> <count> <crc32>
3330
3331 Where address/count indicate a memory area
3332 and crc32 is the correct crc32 which the
3333 area should have.
3334
wdenk56523f12004-07-11 17:40:54 +00003335- CONFIG_LOOPW
3336 Add the "loopw" memory command. This only takes effect if
Simon Glass493f4202017-08-04 16:34:27 -06003337 the memory commands are activated globally (CONFIG_CMD_MEMORY).
wdenk56523f12004-07-11 17:40:54 +00003338
stroese7b466642004-12-16 18:46:55 +00003339- CONFIG_MX_CYCLIC
3340 Add the "mdc" and "mwc" memory commands. These are cyclic
3341 "md/mw" commands.
3342 Examples:
3343
wdenkefe2a4d2004-12-16 21:44:03 +00003344 => mdc.b 10 4 500
stroese7b466642004-12-16 18:46:55 +00003345 This command will print 4 bytes (10,11,12,13) each 500 ms.
3346
wdenkefe2a4d2004-12-16 21:44:03 +00003347 => mwc.l 100 12345678 10
stroese7b466642004-12-16 18:46:55 +00003348 This command will write 12345678 to address 100 all 10 ms.
3349
wdenkefe2a4d2004-12-16 21:44:03 +00003350 This only takes effect if the memory commands are activated
Simon Glass493f4202017-08-04 16:34:27 -06003351 globally (CONFIG_CMD_MEMORY).
stroese7b466642004-12-16 18:46:55 +00003352
wdenk8aa1a2d2005-04-04 12:44:11 +00003353- CONFIG_SKIP_LOWLEVEL_INIT
Rick Chen3fafced2017-12-26 13:55:59 +08003354 [ARM, NDS32, MIPS, RISC-V only] If this variable is defined, then certain
Wolfgang Denk844f07d2010-11-27 23:30:56 +01003355 low level initializations (like setting up the memory
3356 controller) are omitted and/or U-Boot does not
3357 relocate itself into RAM.
wdenk8aa1a2d2005-04-04 12:44:11 +00003358
Wolfgang Denk844f07d2010-11-27 23:30:56 +01003359 Normally this variable MUST NOT be defined. The only
3360 exception is when U-Boot is loaded (to RAM) by some
3361 other boot loader or by a debugger which performs
3362 these initializations itself.
wdenk8aa1a2d2005-04-04 12:44:11 +00003363
Simon Glassb5bd0982016-05-05 07:28:06 -06003364- CONFIG_SKIP_LOWLEVEL_INIT_ONLY
3365 [ARM926EJ-S only] This allows just the call to lowlevel_init()
yeongjun Kim90211f72016-07-20 22:56:12 +09003366 to be skipped. The normal CP15 init (such as enabling the
Simon Glassb5bd0982016-05-05 07:28:06 -06003367 instruction cache) is still performed.
3368
Aneesh V401bb302011-07-13 05:11:07 +00003369- CONFIG_SPL_BUILD
Magnus Liljadf812382009-06-13 20:50:00 +02003370 Modifies the behaviour of start.S when compiling a loader
3371 that is executed before the actual U-Boot. E.g. when
3372 compiling a NAND SPL.
wdenk400558b2005-04-02 23:52:25 +00003373
Ying Zhang3aa29de2013-08-16 15:16:15 +08003374- CONFIG_TPL_BUILD
3375 Modifies the behaviour of start.S when compiling a loader
3376 that is executed after the SPL and before the actual U-Boot.
3377 It is loaded by the SPL.
3378
Ying Zhang5df572f2013-05-20 14:07:23 +08003379- CONFIG_SYS_MPC85XX_NO_RESETVEC
3380 Only for 85xx systems. If this variable is specified, the section
3381 .resetvec is not kept and the section .bootpg is placed in the
3382 previous 4k of the .text section.
3383
Simon Glass4213fc22013-02-24 17:33:14 +00003384- CONFIG_ARCH_MAP_SYSMEM
3385 Generally U-Boot (and in particular the md command) uses
3386 effective address. It is therefore not necessary to regard
3387 U-Boot address as virtual addresses that need to be translated
3388 to physical addresses. However, sandbox requires this, since
3389 it maintains its own little RAM buffer which contains all
3390 addressable memory. This option causes some memory accesses
3391 to be mapped through map_sysmem() / unmap_sysmem().
3392
Simon Glass588a13f2013-02-14 04:18:54 +00003393- CONFIG_X86_RESET_VECTOR
3394 If defined, the x86 reset vector code is included. This is not
3395 needed when U-Boot is running from Coreboot.
Gabe Blackb16f5212012-11-27 21:08:06 +00003396
Karicheri, Muralidharan999d7d32014-04-04 13:16:50 -04003397- CONFIG_SYS_NAND_NO_SUBPAGE_WRITE
3398 Option to disable subpage write in NAND driver
3399 driver that uses this:
3400 drivers/mtd/nand/davinci_nand.c
3401
Timur Tabif2717b42011-11-22 09:21:25 -06003402Freescale QE/FMAN Firmware Support:
3403-----------------------------------
3404
3405The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the
3406loading of "firmware", which is encoded in the QE firmware binary format.
3407This firmware often needs to be loaded during U-Boot booting, so macros
3408are used to identify the storage device (NOR flash, SPI, etc) and the address
3409within that device.
3410
Zhao Qiangdcf1d772014-03-21 16:21:44 +08003411- CONFIG_SYS_FMAN_FW_ADDR
3412 The address in the storage device where the FMAN microcode is located. The
3413 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro
3414 is also specified.
3415
3416- CONFIG_SYS_QE_FW_ADDR
3417 The address in the storage device where the QE microcode is located. The
Timur Tabif2717b42011-11-22 09:21:25 -06003418 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro
3419 is also specified.
3420
3421- CONFIG_SYS_QE_FMAN_FW_LENGTH
3422 The maximum possible size of the firmware. The firmware binary format
3423 has a field that specifies the actual size of the firmware, but it
3424 might not be possible to read any part of the firmware unless some
3425 local storage is allocated to hold the entire firmware first.
3426
3427- CONFIG_SYS_QE_FMAN_FW_IN_NOR
3428 Specifies that QE/FMAN firmware is located in NOR flash, mapped as
3429 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the
3430 virtual address in NOR flash.
3431
3432- CONFIG_SYS_QE_FMAN_FW_IN_NAND
3433 Specifies that QE/FMAN firmware is located in NAND flash.
3434 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash.
3435
3436- CONFIG_SYS_QE_FMAN_FW_IN_MMC
3437 Specifies that QE/FMAN firmware is located on the primary SD/MMC
3438 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
3439
Liu Gang292dc6c2012-03-08 00:33:18 +00003440- CONFIG_SYS_QE_FMAN_FW_IN_REMOTE
3441 Specifies that QE/FMAN firmware is located in the remote (master)
3442 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which
Liu Gangfc54c7f2012-08-09 05:10:01 +00003443 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound
3444 window->master inbound window->master LAW->the ucode address in
3445 master's memory space.
Timur Tabif2717b42011-11-22 09:21:25 -06003446
J. German Riverab940ca62014-06-23 15:15:55 -07003447Freescale Layerscape Management Complex Firmware Support:
3448---------------------------------------------------------
3449The Freescale Layerscape Management Complex (MC) supports the loading of
3450"firmware".
3451This firmware often needs to be loaded during U-Boot booting, so macros
3452are used to identify the storage device (NOR flash, SPI, etc) and the address
3453within that device.
3454
3455- CONFIG_FSL_MC_ENET
3456 Enable the MC driver for Layerscape SoCs.
3457
Prabhakar Kushwaha5c055082015-06-02 10:55:52 +05303458Freescale Layerscape Debug Server Support:
3459-------------------------------------------
3460The Freescale Layerscape Debug Server Support supports the loading of
3461"Debug Server firmware" and triggering SP boot-rom.
3462This firmware often needs to be loaded during U-Boot booting.
3463
York Sunc0492142015-12-07 11:08:58 -08003464- CONFIG_SYS_MC_RSV_MEM_ALIGN
3465 Define alignment of reserved memory MC requires
Prabhakar Kushwaha5c055082015-06-02 10:55:52 +05303466
Paul Kocialkowskif3f431a2015-07-26 18:48:15 +02003467Reproducible builds
3468-------------------
3469
3470In order to achieve reproducible builds, timestamps used in the U-Boot build
3471process have to be set to a fixed value.
3472
3473This is done using the SOURCE_DATE_EPOCH environment variable.
3474SOURCE_DATE_EPOCH is to be set on the build host's shell, not as a configuration
3475option for U-Boot or an environment variable in U-Boot.
3476
3477SOURCE_DATE_EPOCH should be set to a number of seconds since the epoch, in UTC.
3478
wdenkc6097192002-11-03 00:24:07 +00003479Building the Software:
3480======================
3481
Wolfgang Denk218ca722008-03-26 10:40:12 +01003482Building U-Boot has been tested in several native build environments
3483and in many different cross environments. Of course we cannot support
3484all possibly existing versions of cross development tools in all
3485(potentially obsolete) versions. In case of tool chain problems we
3486recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK)
3487which is extensively used to build and test U-Boot.
wdenkc6097192002-11-03 00:24:07 +00003488
Wolfgang Denk218ca722008-03-26 10:40:12 +01003489If you are not using a native environment, it is assumed that you
3490have GNU cross compiling tools available in your path. In this case,
3491you must set the environment variable CROSS_COMPILE in your shell.
3492Note that no changes to the Makefile or any other source files are
3493necessary. For example using the ELDK on a 4xx CPU, please enter:
wdenkc6097192002-11-03 00:24:07 +00003494
Wolfgang Denk218ca722008-03-26 10:40:12 +01003495 $ CROSS_COMPILE=ppc_4xx-
3496 $ export CROSS_COMPILE
wdenkc6097192002-11-03 00:24:07 +00003497
Peter Tyser2f8d3962009-03-13 18:54:51 -05003498Note: If you wish to generate Windows versions of the utilities in
3499 the tools directory you can use the MinGW toolchain
3500 (http://www.mingw.org). Set your HOST tools to the MinGW
3501 toolchain and execute 'make tools'. For example:
3502
3503 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools
3504
3505 Binaries such as tools/mkimage.exe will be created which can
3506 be executed on computers running Windows.
3507
Wolfgang Denk218ca722008-03-26 10:40:12 +01003508U-Boot is intended to be simple to build. After installing the
3509sources you must configure U-Boot for one specific board type. This
wdenkc6097192002-11-03 00:24:07 +00003510is done by typing:
3511
Holger Freytherab584d62014-08-04 09:26:05 +02003512 make NAME_defconfig
wdenkc6097192002-11-03 00:24:07 +00003513
Holger Freytherab584d62014-08-04 09:26:05 +02003514where "NAME_defconfig" is the name of one of the existing configu-
Michael Jones4d675ae2012-03-15 22:48:10 +00003515rations; see boards.cfg for supported names.
wdenk54387ac2003-10-08 22:45:44 +00003516
wdenk2729af92004-05-03 20:45:30 +00003517Note: for some board special configuration names may exist; check if
3518 additional information is available from the board vendor; for
3519 instance, the TQM823L systems are available without (standard)
3520 or with LCD support. You can select such additional "features"
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02003521 when choosing the configuration, i. e.
wdenkc6097192002-11-03 00:24:07 +00003522
Holger Freytherab584d62014-08-04 09:26:05 +02003523 make TQM823L_defconfig
wdenk2729af92004-05-03 20:45:30 +00003524 - will configure for a plain TQM823L, i. e. no LCD support
wdenkc6097192002-11-03 00:24:07 +00003525
Holger Freytherab584d62014-08-04 09:26:05 +02003526 make TQM823L_LCD_defconfig
wdenk2729af92004-05-03 20:45:30 +00003527 - will configure for a TQM823L with U-Boot console on LCD
wdenkc6097192002-11-03 00:24:07 +00003528
wdenk2729af92004-05-03 20:45:30 +00003529 etc.
wdenkc6097192002-11-03 00:24:07 +00003530
wdenkc6097192002-11-03 00:24:07 +00003531
wdenk2729af92004-05-03 20:45:30 +00003532Finally, type "make all", and you should get some working U-Boot
3533images ready for download to / installation on your system:
wdenkc6097192002-11-03 00:24:07 +00003534
wdenk2729af92004-05-03 20:45:30 +00003535- "u-boot.bin" is a raw binary image
3536- "u-boot" is an image in ELF binary format
3537- "u-boot.srec" is in Motorola S-Record format
wdenkc6097192002-11-03 00:24:07 +00003538
Marian Balakowiczbaf31242006-09-07 17:25:40 +02003539By default the build is performed locally and the objects are saved
3540in the source directory. One of the two methods can be used to change
3541this behavior and build U-Boot to some external directory:
3542
35431. Add O= to the make command line invocations:
3544
3545 make O=/tmp/build distclean
Holger Freytherab584d62014-08-04 09:26:05 +02003546 make O=/tmp/build NAME_defconfig
Marian Balakowiczbaf31242006-09-07 17:25:40 +02003547 make O=/tmp/build all
3548
Timo Ketolaadbba992014-11-06 14:39:05 +020035492. Set environment variable KBUILD_OUTPUT to point to the desired location:
Marian Balakowiczbaf31242006-09-07 17:25:40 +02003550
Timo Ketolaadbba992014-11-06 14:39:05 +02003551 export KBUILD_OUTPUT=/tmp/build
Marian Balakowiczbaf31242006-09-07 17:25:40 +02003552 make distclean
Holger Freytherab584d62014-08-04 09:26:05 +02003553 make NAME_defconfig
Marian Balakowiczbaf31242006-09-07 17:25:40 +02003554 make all
3555
Timo Ketolaadbba992014-11-06 14:39:05 +02003556Note that the command line "O=" setting overrides the KBUILD_OUTPUT environment
Marian Balakowiczbaf31242006-09-07 17:25:40 +02003557variable.
3558
Daniel Schwierzeck215bb1c2018-01-26 16:31:04 +01003559User specific CPPFLAGS, AFLAGS and CFLAGS can be passed to the compiler by
3560setting the according environment variables KCPPFLAGS, KAFLAGS and KCFLAGS.
3561For example to treat all compiler warnings as errors:
3562
3563 make KCFLAGS=-Werror
wdenkc6097192002-11-03 00:24:07 +00003564
wdenk2729af92004-05-03 20:45:30 +00003565Please be aware that the Makefiles assume you are using GNU make, so
3566for instance on NetBSD you might need to use "gmake" instead of
3567native "make".
wdenkc6097192002-11-03 00:24:07 +00003568
wdenkc6097192002-11-03 00:24:07 +00003569
wdenk2729af92004-05-03 20:45:30 +00003570If the system board that you have is not listed, then you will need
3571to port U-Boot to your hardware platform. To do this, follow these
3572steps:
wdenkc6097192002-11-03 00:24:07 +00003573
Phil Sutter3c1496c2015-12-25 14:41:18 +010035741. Create a new directory to hold your board specific code. Add any
wdenk2729af92004-05-03 20:45:30 +00003575 files you need. In your board directory, you will need at least
Phil Sutter3c1496c2015-12-25 14:41:18 +01003576 the "Makefile" and a "<board>.c".
35772. Create a new configuration file "include/configs/<board>.h" for
3578 your board.
wdenk2729af92004-05-03 20:45:30 +000035793. If you're porting U-Boot to a new CPU, then also create a new
3580 directory to hold your CPU specific code. Add any files you need.
Holger Freytherab584d62014-08-04 09:26:05 +020035814. Run "make <board>_defconfig" with your new name.
wdenk2729af92004-05-03 20:45:30 +000035825. Type "make", and you should get a working "u-boot.srec" file
3583 to be installed on your target system.
35846. Debug and solve any problems that might arise.
3585 [Of course, this last step is much harder than it sounds.]
wdenkc6097192002-11-03 00:24:07 +00003586
wdenkc6097192002-11-03 00:24:07 +00003587
wdenk2729af92004-05-03 20:45:30 +00003588Testing of U-Boot Modifications, Ports to New Hardware, etc.:
3589==============================================================
wdenkc6097192002-11-03 00:24:07 +00003590
Wolfgang Denk218ca722008-03-26 10:40:12 +01003591If you have modified U-Boot sources (for instance added a new board
3592or support for new devices, a new CPU, etc.) you are expected to
wdenk2729af92004-05-03 20:45:30 +00003593provide feedback to the other developers. The feedback normally takes
3594the form of a "patch", i. e. a context diff against a certain (latest
Wolfgang Denk218ca722008-03-26 10:40:12 +01003595official or latest in the git repository) version of U-Boot sources.
wdenkc6097192002-11-03 00:24:07 +00003596
Wolfgang Denk218ca722008-03-26 10:40:12 +01003597But before you submit such a patch, please verify that your modifi-
3598cation did not break existing code. At least make sure that *ALL* of
wdenk2729af92004-05-03 20:45:30 +00003599the supported boards compile WITHOUT ANY compiler warnings. To do so,
Simon Glass6de80f22016-07-27 20:33:08 -06003600just run the buildman script (tools/buildman/buildman), which will
3601configure and build U-Boot for ALL supported system. Be warned, this
3602will take a while. Please see the buildman README, or run 'buildman -H'
3603for documentation.
Marian Balakowiczbaf31242006-09-07 17:25:40 +02003604
3605
wdenk2729af92004-05-03 20:45:30 +00003606See also "U-Boot Porting Guide" below.
wdenkc6097192002-11-03 00:24:07 +00003607
wdenkc6097192002-11-03 00:24:07 +00003608
wdenk2729af92004-05-03 20:45:30 +00003609Monitor Commands - Overview:
3610============================
wdenkc6097192002-11-03 00:24:07 +00003611
wdenk2729af92004-05-03 20:45:30 +00003612go - start application at address 'addr'
3613run - run commands in an environment variable
3614bootm - boot application image from memory
3615bootp - boot image via network using BootP/TFTP protocol
Marek Vasut44f074c2012-03-14 21:52:45 +00003616bootz - boot zImage from memory
wdenk2729af92004-05-03 20:45:30 +00003617tftpboot- boot image via network using TFTP protocol
3618 and env variables "ipaddr" and "serverip"
3619 (and eventually "gatewayip")
Simon Glass1fb7cd42011-10-24 18:00:07 +00003620tftpput - upload a file via network using TFTP protocol
wdenk2729af92004-05-03 20:45:30 +00003621rarpboot- boot image via network using RARP/TFTP protocol
3622diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
3623loads - load S-Record file over serial line
3624loadb - load binary file over serial line (kermit mode)
3625md - memory display
3626mm - memory modify (auto-incrementing)
3627nm - memory modify (constant address)
3628mw - memory write (fill)
3629cp - memory copy
3630cmp - memory compare
3631crc32 - checksum calculation
Peter Tyser0f89c542009-04-18 22:34:03 -05003632i2c - I2C sub-system
wdenk2729af92004-05-03 20:45:30 +00003633sspi - SPI utility commands
3634base - print or set address offset
3635printenv- print environment variables
3636setenv - set environment variables
3637saveenv - save environment variables to persistent storage
3638protect - enable or disable FLASH write protection
3639erase - erase FLASH memory
3640flinfo - print FLASH memory information
Karl O. Pinc10635af2012-08-03 05:57:21 +00003641nand - NAND memory operations (see doc/README.nand)
wdenk2729af92004-05-03 20:45:30 +00003642bdinfo - print Board Info structure
3643iminfo - print header information for application image
3644coninfo - print console devices and informations
3645ide - IDE sub-system
3646loop - infinite loop on address range
wdenk56523f12004-07-11 17:40:54 +00003647loopw - infinite write loop on address range
wdenk2729af92004-05-03 20:45:30 +00003648mtest - simple RAM test
3649icache - enable or disable instruction cache
3650dcache - enable or disable data cache
3651reset - Perform RESET of the CPU
3652echo - echo args to console
3653version - print monitor version
3654help - print online help
3655? - alias for 'help'
wdenkc6097192002-11-03 00:24:07 +00003656
wdenkc6097192002-11-03 00:24:07 +00003657
wdenk2729af92004-05-03 20:45:30 +00003658Monitor Commands - Detailed Description:
3659========================================
wdenkc6097192002-11-03 00:24:07 +00003660
wdenk2729af92004-05-03 20:45:30 +00003661TODO.
wdenkc6097192002-11-03 00:24:07 +00003662
wdenk2729af92004-05-03 20:45:30 +00003663For now: just type "help <command>".
wdenkc6097192002-11-03 00:24:07 +00003664
3665
wdenk2729af92004-05-03 20:45:30 +00003666Environment Variables:
3667======================
wdenkc6097192002-11-03 00:24:07 +00003668
wdenk2729af92004-05-03 20:45:30 +00003669U-Boot supports user configuration using Environment Variables which
3670can be made persistent by saving to Flash memory.
wdenkc6097192002-11-03 00:24:07 +00003671
wdenk2729af92004-05-03 20:45:30 +00003672Environment Variables are set using "setenv", printed using
3673"printenv", and saved to Flash using "saveenv". Using "setenv"
3674without a value can be used to delete a variable from the
3675environment. As long as you don't save the environment you are
3676working with an in-memory copy. In case the Flash area containing the
3677environment is erased by accident, a default environment is provided.
wdenkc6097192002-11-03 00:24:07 +00003678
Wolfgang Denkc96f86e2010-01-17 23:55:53 +01003679Some configuration options can be set using Environment Variables.
3680
3681List of environment variables (most likely not complete):
wdenkc6097192002-11-03 00:24:07 +00003682
wdenk2729af92004-05-03 20:45:30 +00003683 baudrate - see CONFIG_BAUDRATE
wdenkc6097192002-11-03 00:24:07 +00003684
wdenk2729af92004-05-03 20:45:30 +00003685 bootdelay - see CONFIG_BOOTDELAY
wdenkc6097192002-11-03 00:24:07 +00003686
wdenk2729af92004-05-03 20:45:30 +00003687 bootcmd - see CONFIG_BOOTCOMMAND
wdenkc6097192002-11-03 00:24:07 +00003688
wdenk2729af92004-05-03 20:45:30 +00003689 bootargs - Boot arguments when booting an RTOS image
wdenkc6097192002-11-03 00:24:07 +00003690
wdenk2729af92004-05-03 20:45:30 +00003691 bootfile - Name of the image to load with TFTP
wdenkc6097192002-11-03 00:24:07 +00003692
Bartlomiej Sieka7d721e32008-04-14 15:44:16 +02003693 bootm_low - Memory range available for image processing in the bootm
3694 command can be restricted. This variable is given as
3695 a hexadecimal number and defines lowest address allowed
3696 for use by the bootm command. See also "bootm_size"
3697 environment variable. Address defined by "bootm_low" is
3698 also the base of the initial memory mapping for the Linux
Grant Likelyc3624e62011-03-28 09:58:43 +00003699 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and
3700 bootm_mapsize.
3701
Wolfgang Denkc0f40852011-10-26 10:21:21 +00003702 bootm_mapsize - Size of the initial memory mapping for the Linux kernel.
Grant Likelyc3624e62011-03-28 09:58:43 +00003703 This variable is given as a hexadecimal number and it
3704 defines the size of the memory region starting at base
3705 address bootm_low that is accessible by the Linux kernel
3706 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used
3707 as the default value if it is defined, and bootm_size is
3708 used otherwise.
Bartlomiej Sieka7d721e32008-04-14 15:44:16 +02003709
3710 bootm_size - Memory range available for image processing in the bootm
3711 command can be restricted. This variable is given as
3712 a hexadecimal number and defines the size of the region
3713 allowed for use by the bootm command. See also "bootm_low"
3714 environment variable.
3715
Bartlomiej Sieka4bae9092008-10-01 15:26:31 +02003716 updatefile - Location of the software update file on a TFTP server, used
3717 by the automatic software update feature. Please refer to
3718 documentation in doc/README.update for more details.
3719
wdenk2729af92004-05-03 20:45:30 +00003720 autoload - if set to "no" (any string beginning with 'n'),
3721 "bootp" will just load perform a lookup of the
3722 configuration from the BOOTP server, but not try to
3723 load any image using TFTP
wdenkc6097192002-11-03 00:24:07 +00003724
wdenk2729af92004-05-03 20:45:30 +00003725 autostart - if set to "yes", an image loaded using the "bootp",
3726 "rarpboot", "tftpboot" or "diskboot" commands will
3727 be automatically started (by internally calling
3728 "bootm")
wdenkc6097192002-11-03 00:24:07 +00003729
wdenk2729af92004-05-03 20:45:30 +00003730 If set to "no", a standalone image passed to the
3731 "bootm" command will be copied to the load address
3732 (and eventually uncompressed), but NOT be started.
3733 This can be used to load and uncompress arbitrary
3734 data.
wdenkc6097192002-11-03 00:24:07 +00003735
David A. Longa28afca2011-07-09 16:40:19 -04003736 fdt_high - if set this restricts the maximum address that the
3737 flattened device tree will be copied into upon boot.
Shawn Guofa34f6b2012-01-09 21:54:08 +00003738 For example, if you have a system with 1 GB memory
3739 at physical address 0x10000000, while Linux kernel
3740 only recognizes the first 704 MB as low memory, you
3741 may need to set fdt_high as 0x3C000000 to have the
3742 device tree blob be copied to the maximum address
3743 of the 704 MB low memory, so that Linux kernel can
3744 access it during the boot procedure.
3745
David A. Longa28afca2011-07-09 16:40:19 -04003746 If this is set to the special value 0xFFFFFFFF then
3747 the fdt will not be copied at all on boot. For this
3748 to work it must reside in writable memory, have
3749 sufficient padding on the end of it for u-boot to
3750 add the information it needs into it, and the memory
3751 must be accessible by the kernel.
3752
Simon Glasseea63e02011-10-24 19:15:34 +00003753 fdtcontroladdr- if set this is the address of the control flattened
3754 device tree used by U-Boot when CONFIG_OF_CONTROL is
3755 defined.
3756
wdenk17ea1172004-06-06 21:51:03 +00003757 i2cfast - (PPC405GP|PPC405EP only)
3758 if set to 'y' configures Linux I2C driver for fast
3759 mode (400kHZ). This environment variable is used in
3760 initialization code. So, for changes to be effective
3761 it must be saved and board must be reset.
3762
wdenk2729af92004-05-03 20:45:30 +00003763 initrd_high - restrict positioning of initrd images:
3764 If this variable is not set, initrd images will be
3765 copied to the highest possible address in RAM; this
3766 is usually what you want since it allows for
3767 maximum initrd size. If for some reason you want to
3768 make sure that the initrd image is loaded below the
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02003769 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment
wdenk2729af92004-05-03 20:45:30 +00003770 variable to a value of "no" or "off" or "0".
3771 Alternatively, you can set it to a maximum upper
3772 address to use (U-Boot will still check that it
3773 does not overwrite the U-Boot stack and data).
wdenkc6097192002-11-03 00:24:07 +00003774
wdenk2729af92004-05-03 20:45:30 +00003775 For instance, when you have a system with 16 MB
3776 RAM, and want to reserve 4 MB from use by Linux,
3777 you can do this by adding "mem=12M" to the value of
3778 the "bootargs" variable. However, now you must make
3779 sure that the initrd image is placed in the first
3780 12 MB as well - this can be done with
wdenkc6097192002-11-03 00:24:07 +00003781
wdenk2729af92004-05-03 20:45:30 +00003782 setenv initrd_high 00c00000
wdenkc6097192002-11-03 00:24:07 +00003783
wdenk2729af92004-05-03 20:45:30 +00003784 If you set initrd_high to 0xFFFFFFFF, this is an
3785 indication to U-Boot that all addresses are legal
3786 for the Linux kernel, including addresses in flash
3787 memory. In this case U-Boot will NOT COPY the
3788 ramdisk at all. This may be useful to reduce the
3789 boot time on your system, but requires that this
3790 feature is supported by your Linux kernel.
wdenk4a6fd342003-04-12 23:38:12 +00003791
wdenk2729af92004-05-03 20:45:30 +00003792 ipaddr - IP address; needed for tftpboot command
wdenkc6097192002-11-03 00:24:07 +00003793
wdenk2729af92004-05-03 20:45:30 +00003794 loadaddr - Default load address for commands like "bootp",
3795 "rarpboot", "tftpboot", "loadb" or "diskboot"
wdenkc6097192002-11-03 00:24:07 +00003796
wdenk2729af92004-05-03 20:45:30 +00003797 loads_echo - see CONFIG_LOADS_ECHO
wdenkc6097192002-11-03 00:24:07 +00003798
wdenk2729af92004-05-03 20:45:30 +00003799 serverip - TFTP server IP address; needed for tftpboot command
wdenk38b99262003-05-23 23:18:21 +00003800
wdenk2729af92004-05-03 20:45:30 +00003801 bootretry - see CONFIG_BOOT_RETRY_TIME
wdenkc6097192002-11-03 00:24:07 +00003802
wdenk2729af92004-05-03 20:45:30 +00003803 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
wdenkc6097192002-11-03 00:24:07 +00003804
wdenk2729af92004-05-03 20:45:30 +00003805 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
wdenkc6097192002-11-03 00:24:07 +00003806
Mike Frysingere2a53452011-10-02 10:01:27 +00003807 ethprime - controls which interface is used first.
wdenkc6097192002-11-03 00:24:07 +00003808
Mike Frysingere2a53452011-10-02 10:01:27 +00003809 ethact - controls which interface is currently active.
3810 For example you can do the following
wdenkc6097192002-11-03 00:24:07 +00003811
Heiko Schocher48690d82010-07-20 17:45:02 +02003812 => setenv ethact FEC
3813 => ping 192.168.0.1 # traffic sent on FEC
3814 => setenv ethact SCC
3815 => ping 10.0.0.1 # traffic sent on SCC
wdenkc6097192002-11-03 00:24:07 +00003816
Matthias Fuchse1692572008-01-17 07:45:05 +01003817 ethrotate - When set to "no" U-Boot does not go through all
3818 available network interfaces.
3819 It just stays at the currently selected interface.
3820
Wolfgang Denkc96f86e2010-01-17 23:55:53 +01003821 netretry - When set to "no" each network operation will
wdenk2729af92004-05-03 20:45:30 +00003822 either succeed or fail without retrying.
3823 When set to "once" the network operation will
3824 fail when all the available network interfaces
3825 are tried once without success.
3826 Useful on scripts which control the retry operation
3827 themselves.
wdenkc6097192002-11-03 00:24:07 +00003828
Jean-Christophe PLAGNIOL-VILLARDb4e2f892009-01-31 09:53:39 +01003829 npe_ucode - set load address for the NPE microcode
Jean-Christophe PLAGNIOL-VILLARDa1cf0272008-01-07 08:41:34 +01003830
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08003831 silent_linux - If set then Linux will be told to boot silently, by
Simon Glass8d51aac2013-07-16 20:10:00 -07003832 changing the console to be empty. If "yes" it will be
3833 made silent. If "no" it will not be made silent. If
3834 unset, then it will be made silent if the U-Boot console
3835 is silent.
3836
Albert ARIBAUD \(3ADEV\)f5fb7342015-10-12 00:02:57 +02003837 tftpsrcp - If this is set, the value is used for TFTP's
Wolfgang Denkecb0ccd2005-09-24 22:37:32 +02003838 UDP source port.
3839
Albert ARIBAUD \(3ADEV\)f5fb7342015-10-12 00:02:57 +02003840 tftpdstp - If this is set, the value is used for TFTP's UDP
Wolfgang Denk28cb9372005-09-24 23:25:46 +02003841 destination port instead of the Well Know Port 69.
3842
Wolfgang Denkc96f86e2010-01-17 23:55:53 +01003843 tftpblocksize - Block size to use for TFTP transfers; if not set,
3844 we use the TFTP server's default block size
3845
3846 tftptimeout - Retransmission timeout for TFTP packets (in milli-
3847 seconds, minimum value is 1000 = 1 second). Defines
3848 when a packet is considered to be lost so it has to
3849 be retransmitted. The default is 5000 = 5 seconds.
3850 Lowering this value may make downloads succeed
3851 faster in networks with high packet loss rates or
3852 with unreliable TFTP servers.
3853
Albert ARIBAUD \(3ADEV\)f5fb7342015-10-12 00:02:57 +02003854 tftptimeoutcountmax - maximum count of TFTP timeouts (no
3855 unit, minimum value = 0). Defines how many timeouts
3856 can happen during a single file transfer before that
3857 transfer is aborted. The default is 10, and 0 means
3858 'no timeouts allowed'. Increasing this value may help
3859 downloads succeed with high packet loss rates, or with
3860 unreliable TFTP servers or client hardware.
3861
Wolfgang Denkc96f86e2010-01-17 23:55:53 +01003862 vlan - When set to a value < 4095 the traffic over
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02003863 Ethernet is encapsulated/received over 802.1q
wdenk2729af92004-05-03 20:45:30 +00003864 VLAN tagged frames.
wdenka3d991b2004-04-15 21:48:45 +00003865
Alexandre Messier50768f52016-02-01 17:08:57 -05003866 bootpretryperiod - Period during which BOOTP/DHCP sends retries.
3867 Unsigned value, in milliseconds. If not set, the period will
3868 be either the default (28000), or a value based on
3869 CONFIG_NET_RETRY_COUNT, if defined. This value has
3870 precedence over the valu based on CONFIG_NET_RETRY_COUNT.
3871
Jason Hobbsdc0b7b02011-08-31 05:37:28 +00003872The following image location variables contain the location of images
3873used in booting. The "Image" column gives the role of the image and is
3874not an environment variable name. The other columns are environment
3875variable names. "File Name" gives the name of the file on a TFTP
3876server, "RAM Address" gives the location in RAM the image will be
3877loaded to, and "Flash Location" gives the image's address in NOR
3878flash or offset in NAND flash.
3879
3880*Note* - these variables don't have to be defined for all boards, some
Fabio Estevamaed9fed2015-04-25 18:53:10 -03003881boards currently use other variables for these purposes, and some
Jason Hobbsdc0b7b02011-08-31 05:37:28 +00003882boards use these variables for other purposes.
3883
Wolfgang Denkc0f40852011-10-26 10:21:21 +00003884Image File Name RAM Address Flash Location
3885----- --------- ----------- --------------
3886u-boot u-boot u-boot_addr_r u-boot_addr
3887Linux kernel bootfile kernel_addr_r kernel_addr
3888device tree blob fdtfile fdt_addr_r fdt_addr
3889ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr
Jason Hobbsdc0b7b02011-08-31 05:37:28 +00003890
wdenk2729af92004-05-03 20:45:30 +00003891The following environment variables may be used and automatically
3892updated by the network boot commands ("bootp" and "rarpboot"),
3893depending the information provided by your boot server:
wdenka3d991b2004-04-15 21:48:45 +00003894
wdenk2729af92004-05-03 20:45:30 +00003895 bootfile - see above
3896 dnsip - IP address of your Domain Name Server
3897 dnsip2 - IP address of your secondary Domain Name Server
3898 gatewayip - IP address of the Gateway (Router) to use
3899 hostname - Target hostname
3900 ipaddr - see above
3901 netmask - Subnet Mask
3902 rootpath - Pathname of the root filesystem on the NFS server
3903 serverip - see above
wdenka3d991b2004-04-15 21:48:45 +00003904
wdenka3d991b2004-04-15 21:48:45 +00003905
wdenk2729af92004-05-03 20:45:30 +00003906There are two special Environment Variables:
wdenkc6097192002-11-03 00:24:07 +00003907
wdenk2729af92004-05-03 20:45:30 +00003908 serial# - contains hardware identification information such
3909 as type string and/or serial number
3910 ethaddr - Ethernet address
wdenkc6097192002-11-03 00:24:07 +00003911
wdenk2729af92004-05-03 20:45:30 +00003912These variables can be set only once (usually during manufacturing of
3913the board). U-Boot refuses to delete or overwrite these variables
3914once they have been set once.
wdenkc6097192002-11-03 00:24:07 +00003915
3916
wdenk2729af92004-05-03 20:45:30 +00003917Further special Environment Variables:
wdenkc6097192002-11-03 00:24:07 +00003918
wdenk2729af92004-05-03 20:45:30 +00003919 ver - Contains the U-Boot version string as printed
3920 with the "version" command. This variable is
3921 readonly (see CONFIG_VERSION_VARIABLE).
wdenkc6097192002-11-03 00:24:07 +00003922
wdenkc6097192002-11-03 00:24:07 +00003923
wdenk2729af92004-05-03 20:45:30 +00003924Please note that changes to some configuration parameters may take
3925only effect after the next boot (yes, that's just like Windoze :-).
wdenkc6097192002-11-03 00:24:07 +00003926
stroesec1551ea2003-04-04 15:53:41 +00003927
Joe Hershberger170ab112012-12-11 22:16:24 -06003928Callback functions for environment variables:
3929---------------------------------------------
3930
3931For some environment variables, the behavior of u-boot needs to change
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08003932when their values are changed. This functionality allows functions to
Joe Hershberger170ab112012-12-11 22:16:24 -06003933be associated with arbitrary variables. On creation, overwrite, or
3934deletion, the callback will provide the opportunity for some side
3935effect to happen or for the change to be rejected.
3936
3937The callbacks are named and associated with a function using the
3938U_BOOT_ENV_CALLBACK macro in your board or driver code.
3939
3940These callbacks are associated with variables in one of two ways. The
3941static list can be added to by defining CONFIG_ENV_CALLBACK_LIST_STATIC
3942in the board configuration to a string that defines a list of
3943associations. The list must be in the following format:
3944
3945 entry = variable_name[:callback_name]
3946 list = entry[,list]
3947
3948If the callback name is not specified, then the callback is deleted.
3949Spaces are also allowed anywhere in the list.
3950
3951Callbacks can also be associated by defining the ".callbacks" variable
3952with the same list format above. Any association in ".callbacks" will
3953override any association in the static list. You can define
3954CONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08003955".callbacks" environment variable in the default or embedded environment.
Joe Hershberger170ab112012-12-11 22:16:24 -06003956
Joe Hershbergerbdf1fe42015-05-20 14:27:20 -05003957If CONFIG_REGEX is defined, the variable_name above is evaluated as a
3958regular expression. This allows multiple variables to be connected to
3959the same callback without explicitly listing them all out.
3960
Joe Hershberger170ab112012-12-11 22:16:24 -06003961
wdenk2729af92004-05-03 20:45:30 +00003962Command Line Parsing:
3963=====================
stroesec1551ea2003-04-04 15:53:41 +00003964
wdenk2729af92004-05-03 20:45:30 +00003965There are two different command line parsers available with U-Boot:
3966the old "simple" one, and the much more powerful "hush" shell:
stroesec1551ea2003-04-04 15:53:41 +00003967
wdenk2729af92004-05-03 20:45:30 +00003968Old, simple command line parser:
3969--------------------------------
wdenkc6097192002-11-03 00:24:07 +00003970
wdenk2729af92004-05-03 20:45:30 +00003971- supports environment variables (through setenv / saveenv commands)
3972- several commands on one line, separated by ';'
Wolfgang Denkfe126d82005-11-20 21:40:11 +01003973- variable substitution using "... ${name} ..." syntax
wdenk2729af92004-05-03 20:45:30 +00003974- special characters ('$', ';') can be escaped by prefixing with '\',
3975 for example:
Wolfgang Denkfe126d82005-11-20 21:40:11 +01003976 setenv bootcmd bootm \${address}
wdenk2729af92004-05-03 20:45:30 +00003977- You can also escape text by enclosing in single apostrophes, for example:
3978 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
wdenkc6097192002-11-03 00:24:07 +00003979
wdenk2729af92004-05-03 20:45:30 +00003980Hush shell:
3981-----------
wdenkf07771c2003-05-28 08:06:31 +00003982
wdenk2729af92004-05-03 20:45:30 +00003983- similar to Bourne shell, with control structures like
3984 if...then...else...fi, for...do...done; while...do...done,
3985 until...do...done, ...
3986- supports environment ("global") variables (through setenv / saveenv
3987 commands) and local shell variables (through standard shell syntax
3988 "name=value"); only environment variables can be used with "run"
3989 command
wdenkf07771c2003-05-28 08:06:31 +00003990
wdenk2729af92004-05-03 20:45:30 +00003991General rules:
3992--------------
wdenkf07771c2003-05-28 08:06:31 +00003993
wdenk2729af92004-05-03 20:45:30 +00003994(1) If a command line (or an environment variable executed by a "run"
3995 command) contains several commands separated by semicolon, and
3996 one of these commands fails, then the remaining commands will be
3997 executed anyway.
wdenkf07771c2003-05-28 08:06:31 +00003998
wdenk2729af92004-05-03 20:45:30 +00003999(2) If you execute several variables with one call to run (i. e.
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02004000 calling run with a list of variables as arguments), any failing
wdenk2729af92004-05-03 20:45:30 +00004001 command will cause "run" to terminate, i. e. the remaining
4002 variables are not executed.
wdenkf07771c2003-05-28 08:06:31 +00004003
wdenk2729af92004-05-03 20:45:30 +00004004Note for Redundant Ethernet Interfaces:
4005=======================================
wdenkf07771c2003-05-28 08:06:31 +00004006
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02004007Some boards come with redundant Ethernet interfaces; U-Boot supports
wdenk2729af92004-05-03 20:45:30 +00004008such configurations and is capable of automatic selection of a
4009"working" interface when needed. MAC assignment works as follows:
wdenkf07771c2003-05-28 08:06:31 +00004010
wdenk2729af92004-05-03 20:45:30 +00004011Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
4012MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
4013"eth1addr" (=>eth1), "eth2addr", ...
wdenkf07771c2003-05-28 08:06:31 +00004014
wdenk2729af92004-05-03 20:45:30 +00004015If the network interface stores some valid MAC address (for instance
4016in SROM), this is used as default address if there is NO correspon-
4017ding setting in the environment; if the corresponding environment
4018variable is set, this overrides the settings in the card; that means:
wdenkf07771c2003-05-28 08:06:31 +00004019
wdenk2729af92004-05-03 20:45:30 +00004020o If the SROM has a valid MAC address, and there is no address in the
4021 environment, the SROM's address is used.
wdenkc6097192002-11-03 00:24:07 +00004022
wdenk2729af92004-05-03 20:45:30 +00004023o If there is no valid address in the SROM, and a definition in the
4024 environment exists, then the value from the environment variable is
4025 used.
wdenkc6097192002-11-03 00:24:07 +00004026
wdenk2729af92004-05-03 20:45:30 +00004027o If both the SROM and the environment contain a MAC address, and
4028 both addresses are the same, this MAC address is used.
wdenkc6097192002-11-03 00:24:07 +00004029
wdenk2729af92004-05-03 20:45:30 +00004030o If both the SROM and the environment contain a MAC address, and the
4031 addresses differ, the value from the environment is used and a
4032 warning is printed.
wdenkc6097192002-11-03 00:24:07 +00004033
wdenk2729af92004-05-03 20:45:30 +00004034o If neither SROM nor the environment contain a MAC address, an error
Joe Hershbergerbef10142015-05-04 14:55:13 -05004035 is raised. If CONFIG_NET_RANDOM_ETHADDR is defined, then in this case
4036 a random, locally-assigned MAC is used.
wdenkc6097192002-11-03 00:24:07 +00004037
Ben Warrenecee9322010-04-26 11:11:46 -07004038If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses
Wolfgang Denkc0f40852011-10-26 10:21:21 +00004039will be programmed into hardware as part of the initialization process. This
Ben Warrenecee9322010-04-26 11:11:46 -07004040may be skipped by setting the appropriate 'ethmacskip' environment variable.
4041The naming convention is as follows:
4042"ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc.
wdenkc6097192002-11-03 00:24:07 +00004043
wdenk2729af92004-05-03 20:45:30 +00004044Image Formats:
4045==============
wdenkc6097192002-11-03 00:24:07 +00004046
Marian Balakowicz3310c542008-03-12 12:13:13 +01004047U-Boot is capable of booting (and performing other auxiliary operations on)
4048images in two formats:
4049
4050New uImage format (FIT)
4051-----------------------
4052
4053Flexible and powerful format based on Flattened Image Tree -- FIT (similar
4054to Flattened Device Tree). It allows the use of images with multiple
4055components (several kernels, ramdisks, etc.), with contents protected by
4056SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
4057
4058
4059Old uImage format
4060-----------------
4061
4062Old image format is based on binary files which can be basically anything,
4063preceded by a special header; see the definitions in include/image.h for
4064details; basically, the header defines the following image properties:
wdenkc6097192002-11-03 00:24:07 +00004065
wdenk2729af92004-05-03 20:45:30 +00004066* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
4067 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
Peter Tyserf5ed9e32008-09-08 14:56:49 -05004068 LynxOS, pSOS, QNX, RTEMS, INTEGRITY;
4069 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS,
4070 INTEGRITY).
Andy Shevchenkodaab59a2017-07-05 16:25:22 +03004071* Target CPU Architecture (Provisions for Alpha, ARM, Intel x86,
Macpaul Linafc1ce82011-10-19 20:41:11 +00004072 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
Andy Shevchenkodaab59a2017-07-05 16:25:22 +03004073 Currently supported: ARM, Intel x86, MIPS, NDS32, Nios II, PowerPC).
wdenk2729af92004-05-03 20:45:30 +00004074* Compression Type (uncompressed, gzip, bzip2)
4075* Load Address
4076* Entry Point
4077* Image Name
4078* Image Timestamp
wdenkc6097192002-11-03 00:24:07 +00004079
wdenk2729af92004-05-03 20:45:30 +00004080The header is marked by a special Magic Number, and both the header
4081and the data portions of the image are secured against corruption by
4082CRC32 checksums.
wdenkc6097192002-11-03 00:24:07 +00004083
wdenkc6097192002-11-03 00:24:07 +00004084
wdenk2729af92004-05-03 20:45:30 +00004085Linux Support:
4086==============
wdenkc6097192002-11-03 00:24:07 +00004087
wdenk2729af92004-05-03 20:45:30 +00004088Although U-Boot should support any OS or standalone application
4089easily, the main focus has always been on Linux during the design of
4090U-Boot.
wdenkc6097192002-11-03 00:24:07 +00004091
wdenk2729af92004-05-03 20:45:30 +00004092U-Boot includes many features that so far have been part of some
4093special "boot loader" code within the Linux kernel. Also, any
4094"initrd" images to be used are no longer part of one big Linux image;
4095instead, kernel and "initrd" are separate images. This implementation
4096serves several purposes:
wdenkc6097192002-11-03 00:24:07 +00004097
wdenk2729af92004-05-03 20:45:30 +00004098- the same features can be used for other OS or standalone
4099 applications (for instance: using compressed images to reduce the
4100 Flash memory footprint)
wdenkc6097192002-11-03 00:24:07 +00004101
wdenk2729af92004-05-03 20:45:30 +00004102- it becomes much easier to port new Linux kernel versions because
4103 lots of low-level, hardware dependent stuff are done by U-Boot
wdenkc6097192002-11-03 00:24:07 +00004104
wdenk2729af92004-05-03 20:45:30 +00004105- the same Linux kernel image can now be used with different "initrd"
4106 images; of course this also means that different kernel images can
4107 be run with the same "initrd". This makes testing easier (you don't
4108 have to build a new "zImage.initrd" Linux image when you just
4109 change a file in your "initrd"). Also, a field-upgrade of the
4110 software is easier now.
wdenkc6097192002-11-03 00:24:07 +00004111
wdenkc6097192002-11-03 00:24:07 +00004112
wdenk2729af92004-05-03 20:45:30 +00004113Linux HOWTO:
4114============
wdenkc6097192002-11-03 00:24:07 +00004115
wdenk2729af92004-05-03 20:45:30 +00004116Porting Linux to U-Boot based systems:
4117---------------------------------------
wdenkc6097192002-11-03 00:24:07 +00004118
wdenk2729af92004-05-03 20:45:30 +00004119U-Boot cannot save you from doing all the necessary modifications to
4120configure the Linux device drivers for use with your target hardware
4121(no, we don't intend to provide a full virtual machine interface to
4122Linux :-).
wdenkc6097192002-11-03 00:24:07 +00004123
Stefan Roesea47a12b2010-04-15 16:07:28 +02004124But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot).
wdenkc6097192002-11-03 00:24:07 +00004125
wdenk2729af92004-05-03 20:45:30 +00004126Just make sure your machine specific header file (for instance
4127include/asm-ppc/tqm8xx.h) includes the same definition of the Board
Markus Heidelberg1dc30692008-09-07 20:18:27 +02004128Information structure as we define in include/asm-<arch>/u-boot.h,
4129and make sure that your definition of IMAP_ADDR uses the same value
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02004130as your U-Boot configuration in CONFIG_SYS_IMMR.
wdenkc6097192002-11-03 00:24:07 +00004131
Simon Glass2eb31b12014-06-11 23:29:46 -06004132Note that U-Boot now has a driver model, a unified model for drivers.
4133If you are adding a new driver, plumb it into driver model. If there
4134is no uclass available, you are encouraged to create one. See
4135doc/driver-model.
4136
wdenkc6097192002-11-03 00:24:07 +00004137
wdenk2729af92004-05-03 20:45:30 +00004138Configuring the Linux kernel:
4139-----------------------------
wdenkc6097192002-11-03 00:24:07 +00004140
wdenk2729af92004-05-03 20:45:30 +00004141No specific requirements for U-Boot. Make sure you have some root
4142device (initial ramdisk, NFS) for your target system.
wdenkc6097192002-11-03 00:24:07 +00004143
wdenkc6097192002-11-03 00:24:07 +00004144
wdenk2729af92004-05-03 20:45:30 +00004145Building a Linux Image:
4146-----------------------
wdenkc6097192002-11-03 00:24:07 +00004147
wdenk2729af92004-05-03 20:45:30 +00004148With U-Boot, "normal" build targets like "zImage" or "bzImage" are
4149not used. If you use recent kernel source, a new build target
4150"uImage" will exist which automatically builds an image usable by
4151U-Boot. Most older kernels also have support for a "pImage" target,
4152which was introduced for our predecessor project PPCBoot and uses a
4153100% compatible format.
wdenkc6097192002-11-03 00:24:07 +00004154
wdenk2729af92004-05-03 20:45:30 +00004155Example:
wdenkc6097192002-11-03 00:24:07 +00004156
Holger Freytherab584d62014-08-04 09:26:05 +02004157 make TQM850L_defconfig
wdenk2729af92004-05-03 20:45:30 +00004158 make oldconfig
4159 make dep
4160 make uImage
wdenkc6097192002-11-03 00:24:07 +00004161
wdenk2729af92004-05-03 20:45:30 +00004162The "uImage" build target uses a special tool (in 'tools/mkimage') to
4163encapsulate a compressed Linux kernel image with header information,
4164CRC32 checksum etc. for use with U-Boot. This is what we are doing:
wdenkc6097192002-11-03 00:24:07 +00004165
wdenk2729af92004-05-03 20:45:30 +00004166* build a standard "vmlinux" kernel image (in ELF binary format):
wdenkc6097192002-11-03 00:24:07 +00004167
wdenk2729af92004-05-03 20:45:30 +00004168* convert the kernel into a raw binary image:
wdenkc6097192002-11-03 00:24:07 +00004169
wdenk2729af92004-05-03 20:45:30 +00004170 ${CROSS_COMPILE}-objcopy -O binary \
4171 -R .note -R .comment \
4172 -S vmlinux linux.bin
wdenkc6097192002-11-03 00:24:07 +00004173
wdenk2729af92004-05-03 20:45:30 +00004174* compress the binary image:
wdenkc6097192002-11-03 00:24:07 +00004175
wdenk2729af92004-05-03 20:45:30 +00004176 gzip -9 linux.bin
wdenkc6097192002-11-03 00:24:07 +00004177
wdenk2729af92004-05-03 20:45:30 +00004178* package compressed binary image for U-Boot:
wdenk24ee89b2002-11-03 17:56:27 +00004179
wdenk2729af92004-05-03 20:45:30 +00004180 mkimage -A ppc -O linux -T kernel -C gzip \
4181 -a 0 -e 0 -n "Linux Kernel Image" \
4182 -d linux.bin.gz uImage
wdenk24ee89b2002-11-03 17:56:27 +00004183
wdenk24ee89b2002-11-03 17:56:27 +00004184
wdenk2729af92004-05-03 20:45:30 +00004185The "mkimage" tool can also be used to create ramdisk images for use
4186with U-Boot, either separated from the Linux kernel image, or
4187combined into one file. "mkimage" encapsulates the images with a 64
4188byte header containing information about target architecture,
4189operating system, image type, compression method, entry points, time
4190stamp, CRC32 checksums, etc.
wdenk24ee89b2002-11-03 17:56:27 +00004191
wdenk2729af92004-05-03 20:45:30 +00004192"mkimage" can be called in two ways: to verify existing images and
4193print the header information, or to build new images.
wdenk24ee89b2002-11-03 17:56:27 +00004194
wdenk2729af92004-05-03 20:45:30 +00004195In the first form (with "-l" option) mkimage lists the information
4196contained in the header of an existing U-Boot image; this includes
4197checksum verification:
wdenk24ee89b2002-11-03 17:56:27 +00004198
wdenk2729af92004-05-03 20:45:30 +00004199 tools/mkimage -l image
4200 -l ==> list image header information
wdenk24ee89b2002-11-03 17:56:27 +00004201
wdenk2729af92004-05-03 20:45:30 +00004202The second form (with "-d" option) is used to build a U-Boot image
4203from a "data file" which is used as image payload:
wdenk24ee89b2002-11-03 17:56:27 +00004204
wdenk2729af92004-05-03 20:45:30 +00004205 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
4206 -n name -d data_file image
4207 -A ==> set architecture to 'arch'
4208 -O ==> set operating system to 'os'
4209 -T ==> set image type to 'type'
4210 -C ==> set compression type 'comp'
4211 -a ==> set load address to 'addr' (hex)
4212 -e ==> set entry point to 'ep' (hex)
4213 -n ==> set image name to 'name'
4214 -d ==> use image data from 'datafile'
wdenk24ee89b2002-11-03 17:56:27 +00004215
wdenk69459792004-05-29 16:53:29 +00004216Right now, all Linux kernels for PowerPC systems use the same load
4217address (0x00000000), but the entry point address depends on the
4218kernel version:
wdenkc6097192002-11-03 00:24:07 +00004219
wdenk2729af92004-05-03 20:45:30 +00004220- 2.2.x kernels have the entry point at 0x0000000C,
4221- 2.3.x and later kernels have the entry point at 0x00000000.
wdenkc6097192002-11-03 00:24:07 +00004222
wdenk2729af92004-05-03 20:45:30 +00004223So a typical call to build a U-Boot image would read:
wdenkc6097192002-11-03 00:24:07 +00004224
wdenk2729af92004-05-03 20:45:30 +00004225 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
4226 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
Stefan Roesea47a12b2010-04-15 16:07:28 +02004227 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \
wdenk2729af92004-05-03 20:45:30 +00004228 > examples/uImage.TQM850L
4229 Image Name: 2.4.4 kernel for TQM850L
4230 Created: Wed Jul 19 02:34:59 2000
4231 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4232 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
4233 Load Address: 0x00000000
4234 Entry Point: 0x00000000
wdenkc6097192002-11-03 00:24:07 +00004235
wdenk2729af92004-05-03 20:45:30 +00004236To verify the contents of the image (or check for corruption):
wdenkc6097192002-11-03 00:24:07 +00004237
wdenk2729af92004-05-03 20:45:30 +00004238 -> tools/mkimage -l examples/uImage.TQM850L
4239 Image Name: 2.4.4 kernel for TQM850L
4240 Created: Wed Jul 19 02:34:59 2000
4241 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4242 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
4243 Load Address: 0x00000000
4244 Entry Point: 0x00000000
wdenkc6097192002-11-03 00:24:07 +00004245
wdenk2729af92004-05-03 20:45:30 +00004246NOTE: for embedded systems where boot time is critical you can trade
4247speed for memory and install an UNCOMPRESSED image instead: this
4248needs more space in Flash, but boots much faster since it does not
4249need to be uncompressed:
wdenkc6097192002-11-03 00:24:07 +00004250
Stefan Roesea47a12b2010-04-15 16:07:28 +02004251 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz
wdenk2729af92004-05-03 20:45:30 +00004252 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
4253 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
Stefan Roesea47a12b2010-04-15 16:07:28 +02004254 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \
wdenk2729af92004-05-03 20:45:30 +00004255 > examples/uImage.TQM850L-uncompressed
4256 Image Name: 2.4.4 kernel for TQM850L
4257 Created: Wed Jul 19 02:34:59 2000
4258 Image Type: PowerPC Linux Kernel Image (uncompressed)
4259 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
4260 Load Address: 0x00000000
4261 Entry Point: 0x00000000
wdenkc6097192002-11-03 00:24:07 +00004262
wdenkc6097192002-11-03 00:24:07 +00004263
wdenk2729af92004-05-03 20:45:30 +00004264Similar you can build U-Boot images from a 'ramdisk.image.gz' file
4265when your kernel is intended to use an initial ramdisk:
wdenkdb01a2e2004-04-15 23:14:49 +00004266
wdenk2729af92004-05-03 20:45:30 +00004267 -> tools/mkimage -n 'Simple Ramdisk Image' \
4268 > -A ppc -O linux -T ramdisk -C gzip \
4269 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
4270 Image Name: Simple Ramdisk Image
4271 Created: Wed Jan 12 14:01:50 2000
4272 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
4273 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
4274 Load Address: 0x00000000
4275 Entry Point: 0x00000000
wdenkdb01a2e2004-04-15 23:14:49 +00004276
Guilherme Maciel Ferreiraa804b5c2013-12-01 12:43:11 -07004277The "dumpimage" is a tool to disassemble images built by mkimage. Its "-i"
4278option performs the converse operation of the mkimage's second form (the "-d"
4279option). Given an image built by mkimage, the dumpimage extracts a "data file"
4280from the image:
4281
Guilherme Maciel Ferreiraf41f5b72015-01-15 02:54:40 -02004282 tools/dumpimage -i image -T type -p position data_file
4283 -i ==> extract from the 'image' a specific 'data_file'
4284 -T ==> set image type to 'type'
4285 -p ==> 'position' (starting at 0) of the 'data_file' inside the 'image'
Guilherme Maciel Ferreiraa804b5c2013-12-01 12:43:11 -07004286
wdenkdb01a2e2004-04-15 23:14:49 +00004287
wdenk2729af92004-05-03 20:45:30 +00004288Installing a Linux Image:
4289-------------------------
wdenkdb01a2e2004-04-15 23:14:49 +00004290
wdenk2729af92004-05-03 20:45:30 +00004291To downloading a U-Boot image over the serial (console) interface,
4292you must convert the image to S-Record format:
wdenkdb01a2e2004-04-15 23:14:49 +00004293
wdenk2729af92004-05-03 20:45:30 +00004294 objcopy -I binary -O srec examples/image examples/image.srec
wdenkdb01a2e2004-04-15 23:14:49 +00004295
wdenk2729af92004-05-03 20:45:30 +00004296The 'objcopy' does not understand the information in the U-Boot
4297image header, so the resulting S-Record file will be relative to
4298address 0x00000000. To load it to a given address, you need to
4299specify the target address as 'offset' parameter with the 'loads'
4300command.
wdenkc6097192002-11-03 00:24:07 +00004301
wdenk2729af92004-05-03 20:45:30 +00004302Example: install the image to address 0x40100000 (which on the
4303TQM8xxL is in the first Flash bank):
wdenkc6097192002-11-03 00:24:07 +00004304
wdenk2729af92004-05-03 20:45:30 +00004305 => erase 40100000 401FFFFF
wdenkc6097192002-11-03 00:24:07 +00004306
wdenk2729af92004-05-03 20:45:30 +00004307 .......... done
4308 Erased 8 sectors
wdenkc6097192002-11-03 00:24:07 +00004309
wdenk2729af92004-05-03 20:45:30 +00004310 => loads 40100000
4311 ## Ready for S-Record download ...
4312 ~>examples/image.srec
4313 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
4314 ...
4315 15989 15990 15991 15992
4316 [file transfer complete]
4317 [connected]
4318 ## Start Addr = 0x00000000
wdenkc6097192002-11-03 00:24:07 +00004319
4320
wdenk2729af92004-05-03 20:45:30 +00004321You can check the success of the download using the 'iminfo' command;
Wolfgang Denk218ca722008-03-26 10:40:12 +01004322this includes a checksum verification so you can be sure no data
wdenk2729af92004-05-03 20:45:30 +00004323corruption happened:
wdenkc6097192002-11-03 00:24:07 +00004324
wdenk2729af92004-05-03 20:45:30 +00004325 => imi 40100000
wdenkc6097192002-11-03 00:24:07 +00004326
wdenk2729af92004-05-03 20:45:30 +00004327 ## Checking Image at 40100000 ...
4328 Image Name: 2.2.13 for initrd on TQM850L
4329 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4330 Data Size: 335725 Bytes = 327 kB = 0 MB
4331 Load Address: 00000000
4332 Entry Point: 0000000c
4333 Verifying Checksum ... OK
wdenkc6097192002-11-03 00:24:07 +00004334
4335
wdenk2729af92004-05-03 20:45:30 +00004336Boot Linux:
4337-----------
wdenkc6097192002-11-03 00:24:07 +00004338
wdenk2729af92004-05-03 20:45:30 +00004339The "bootm" command is used to boot an application that is stored in
4340memory (RAM or Flash). In case of a Linux kernel image, the contents
4341of the "bootargs" environment variable is passed to the kernel as
4342parameters. You can check and modify this variable using the
4343"printenv" and "setenv" commands:
wdenkc6097192002-11-03 00:24:07 +00004344
4345
wdenk2729af92004-05-03 20:45:30 +00004346 => printenv bootargs
4347 bootargs=root=/dev/ram
wdenkc6097192002-11-03 00:24:07 +00004348
wdenk2729af92004-05-03 20:45:30 +00004349 => 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 +00004350
wdenk2729af92004-05-03 20:45:30 +00004351 => printenv bootargs
4352 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 +00004353
wdenk2729af92004-05-03 20:45:30 +00004354 => bootm 40020000
4355 ## Booting Linux kernel at 40020000 ...
4356 Image Name: 2.2.13 for NFS on TQM850L
4357 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4358 Data Size: 381681 Bytes = 372 kB = 0 MB
4359 Load Address: 00000000
4360 Entry Point: 0000000c
4361 Verifying Checksum ... OK
4362 Uncompressing Kernel Image ... OK
4363 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
4364 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
4365 time_init: decrementer frequency = 187500000/60
4366 Calibrating delay loop... 49.77 BogoMIPS
4367 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
4368 ...
wdenkc6097192002-11-03 00:24:07 +00004369
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02004370If you want to boot a Linux kernel with initial RAM disk, you pass
wdenk2729af92004-05-03 20:45:30 +00004371the memory addresses of both the kernel and the initrd image (PPBCOOT
4372format!) to the "bootm" command:
wdenkc6097192002-11-03 00:24:07 +00004373
wdenk2729af92004-05-03 20:45:30 +00004374 => imi 40100000 40200000
wdenkc6097192002-11-03 00:24:07 +00004375
wdenk2729af92004-05-03 20:45:30 +00004376 ## Checking Image at 40100000 ...
4377 Image Name: 2.2.13 for initrd on TQM850L
4378 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4379 Data Size: 335725 Bytes = 327 kB = 0 MB
4380 Load Address: 00000000
4381 Entry Point: 0000000c
4382 Verifying Checksum ... OK
wdenkc6097192002-11-03 00:24:07 +00004383
wdenk2729af92004-05-03 20:45:30 +00004384 ## Checking Image at 40200000 ...
4385 Image Name: Simple Ramdisk Image
4386 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
4387 Data Size: 566530 Bytes = 553 kB = 0 MB
4388 Load Address: 00000000
4389 Entry Point: 00000000
4390 Verifying Checksum ... OK
wdenkc6097192002-11-03 00:24:07 +00004391
wdenk2729af92004-05-03 20:45:30 +00004392 => bootm 40100000 40200000
4393 ## Booting Linux kernel at 40100000 ...
4394 Image Name: 2.2.13 for initrd on TQM850L
4395 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4396 Data Size: 335725 Bytes = 327 kB = 0 MB
4397 Load Address: 00000000
4398 Entry Point: 0000000c
4399 Verifying Checksum ... OK
4400 Uncompressing Kernel Image ... OK
4401 ## Loading RAMDisk Image at 40200000 ...
4402 Image Name: Simple Ramdisk Image
4403 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
4404 Data Size: 566530 Bytes = 553 kB = 0 MB
4405 Load Address: 00000000
4406 Entry Point: 00000000
4407 Verifying Checksum ... OK
4408 Loading Ramdisk ... OK
4409 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
4410 Boot arguments: root=/dev/ram
4411 time_init: decrementer frequency = 187500000/60
4412 Calibrating delay loop... 49.77 BogoMIPS
4413 ...
4414 RAMDISK: Compressed image found at block 0
4415 VFS: Mounted root (ext2 filesystem).
wdenkc6097192002-11-03 00:24:07 +00004416
wdenk2729af92004-05-03 20:45:30 +00004417 bash#
wdenkc6097192002-11-03 00:24:07 +00004418
Matthew McClintock02677682006-06-28 10:41:37 -05004419Boot Linux and pass a flat device tree:
4420-----------
4421
4422First, U-Boot must be compiled with the appropriate defines. See the section
4423titled "Linux Kernel Interface" above for a more in depth explanation. The
4424following is an example of how to start a kernel and pass an updated
4425flat device tree:
4426
4427=> print oftaddr
4428oftaddr=0x300000
4429=> print oft
4430oft=oftrees/mpc8540ads.dtb
4431=> tftp $oftaddr $oft
4432Speed: 1000, full duplex
4433Using TSEC0 device
4434TFTP from server 192.168.1.1; our IP address is 192.168.1.101
4435Filename 'oftrees/mpc8540ads.dtb'.
4436Load address: 0x300000
4437Loading: #
4438done
4439Bytes transferred = 4106 (100a hex)
4440=> tftp $loadaddr $bootfile
4441Speed: 1000, full duplex
4442Using TSEC0 device
4443TFTP from server 192.168.1.1; our IP address is 192.168.1.2
4444Filename 'uImage'.
4445Load address: 0x200000
4446Loading:############
4447done
4448Bytes transferred = 1029407 (fb51f hex)
4449=> print loadaddr
4450loadaddr=200000
4451=> print oftaddr
4452oftaddr=0x300000
4453=> bootm $loadaddr - $oftaddr
4454## Booting image at 00200000 ...
Wolfgang Denka9398e02006-11-27 15:32:42 +01004455 Image Name: Linux-2.6.17-dirty
4456 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4457 Data Size: 1029343 Bytes = 1005.2 kB
Matthew McClintock02677682006-06-28 10:41:37 -05004458 Load Address: 00000000
Wolfgang Denka9398e02006-11-27 15:32:42 +01004459 Entry Point: 00000000
Matthew McClintock02677682006-06-28 10:41:37 -05004460 Verifying Checksum ... OK
4461 Uncompressing Kernel Image ... OK
4462Booting using flat device tree at 0x300000
4463Using MPC85xx ADS machine description
4464Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb
4465[snip]
4466
4467
wdenk2729af92004-05-03 20:45:30 +00004468More About U-Boot Image Types:
4469------------------------------
wdenk6069ff22003-02-28 00:49:47 +00004470
wdenk2729af92004-05-03 20:45:30 +00004471U-Boot supports the following image types:
wdenk6069ff22003-02-28 00:49:47 +00004472
wdenk2729af92004-05-03 20:45:30 +00004473 "Standalone Programs" are directly runnable in the environment
4474 provided by U-Boot; it is expected that (if they behave
4475 well) you can continue to work in U-Boot after return from
4476 the Standalone Program.
4477 "OS Kernel Images" are usually images of some Embedded OS which
4478 will take over control completely. Usually these programs
4479 will install their own set of exception handlers, device
4480 drivers, set up the MMU, etc. - this means, that you cannot
4481 expect to re-enter U-Boot except by resetting the CPU.
4482 "RAMDisk Images" are more or less just data blocks, and their
4483 parameters (address, size) are passed to an OS kernel that is
4484 being started.
4485 "Multi-File Images" contain several images, typically an OS
4486 (Linux) kernel image and one or more data images like
4487 RAMDisks. This construct is useful for instance when you want
4488 to boot over the network using BOOTP etc., where the boot
4489 server provides just a single image file, but you want to get
4490 for instance an OS kernel and a RAMDisk image.
stroesec1551ea2003-04-04 15:53:41 +00004491
wdenk2729af92004-05-03 20:45:30 +00004492 "Multi-File Images" start with a list of image sizes, each
4493 image size (in bytes) specified by an "uint32_t" in network
4494 byte order. This list is terminated by an "(uint32_t)0".
4495 Immediately after the terminating 0 follow the images, one by
4496 one, all aligned on "uint32_t" boundaries (size rounded up to
4497 a multiple of 4 bytes).
stroesec1551ea2003-04-04 15:53:41 +00004498
wdenk2729af92004-05-03 20:45:30 +00004499 "Firmware Images" are binary images containing firmware (like
4500 U-Boot or FPGA images) which usually will be programmed to
4501 flash memory.
stroesec1551ea2003-04-04 15:53:41 +00004502
wdenk2729af92004-05-03 20:45:30 +00004503 "Script files" are command sequences that will be executed by
4504 U-Boot's command interpreter; this feature is especially
4505 useful when you configure U-Boot to use a real shell (hush)
4506 as command interpreter.
wdenk6069ff22003-02-28 00:49:47 +00004507
Marek Vasut44f074c2012-03-14 21:52:45 +00004508Booting the Linux zImage:
4509-------------------------
4510
4511On some platforms, it's possible to boot Linux zImage. This is done
4512using the "bootz" command. The syntax of "bootz" command is the same
4513as the syntax of "bootm" command.
4514
Tom Rini8ac28562013-05-16 11:40:11 -04004515Note, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply
Marek Vasut017e1f32012-03-18 11:47:58 +00004516kernel with raw initrd images. The syntax is slightly different, the
4517address of the initrd must be augmented by it's size, in the following
4518format: "<initrd addres>:<initrd size>".
4519
wdenkc6097192002-11-03 00:24:07 +00004520
wdenk2729af92004-05-03 20:45:30 +00004521Standalone HOWTO:
4522=================
wdenkc6097192002-11-03 00:24:07 +00004523
wdenk2729af92004-05-03 20:45:30 +00004524One of the features of U-Boot is that you can dynamically load and
4525run "standalone" applications, which can use some resources of
4526U-Boot like console I/O functions or interrupt services.
wdenkc6097192002-11-03 00:24:07 +00004527
wdenk2729af92004-05-03 20:45:30 +00004528Two simple examples are included with the sources:
wdenkc6097192002-11-03 00:24:07 +00004529
wdenk2729af92004-05-03 20:45:30 +00004530"Hello World" Demo:
4531-------------------
wdenkc6097192002-11-03 00:24:07 +00004532
wdenk2729af92004-05-03 20:45:30 +00004533'examples/hello_world.c' contains a small "Hello World" Demo
4534application; it is automatically compiled when you build U-Boot.
4535It's configured to run at address 0x00040004, so you can play with it
4536like that:
wdenkc6097192002-11-03 00:24:07 +00004537
wdenk2729af92004-05-03 20:45:30 +00004538 => loads
4539 ## Ready for S-Record download ...
4540 ~>examples/hello_world.srec
4541 1 2 3 4 5 6 7 8 9 10 11 ...
4542 [file transfer complete]
4543 [connected]
4544 ## Start Addr = 0x00040004
wdenkc6097192002-11-03 00:24:07 +00004545
wdenk2729af92004-05-03 20:45:30 +00004546 => go 40004 Hello World! This is a test.
4547 ## Starting application at 0x00040004 ...
4548 Hello World
4549 argc = 7
4550 argv[0] = "40004"
4551 argv[1] = "Hello"
4552 argv[2] = "World!"
4553 argv[3] = "This"
4554 argv[4] = "is"
4555 argv[5] = "a"
4556 argv[6] = "test."
4557 argv[7] = "<NULL>"
4558 Hit any key to exit ...
wdenkc6097192002-11-03 00:24:07 +00004559
wdenk2729af92004-05-03 20:45:30 +00004560 ## Application terminated, rc = 0x0
wdenkc6097192002-11-03 00:24:07 +00004561
wdenk2729af92004-05-03 20:45:30 +00004562Another example, which demonstrates how to register a CPM interrupt
4563handler with the U-Boot code, can be found in 'examples/timer.c'.
4564Here, a CPM timer is set up to generate an interrupt every second.
4565The interrupt service routine is trivial, just printing a '.'
4566character, but this is just a demo program. The application can be
4567controlled by the following keys:
wdenkc6097192002-11-03 00:24:07 +00004568
wdenk2729af92004-05-03 20:45:30 +00004569 ? - print current values og the CPM Timer registers
4570 b - enable interrupts and start timer
4571 e - stop timer and disable interrupts
4572 q - quit application
wdenkc6097192002-11-03 00:24:07 +00004573
wdenk2729af92004-05-03 20:45:30 +00004574 => loads
4575 ## Ready for S-Record download ...
4576 ~>examples/timer.srec
4577 1 2 3 4 5 6 7 8 9 10 11 ...
4578 [file transfer complete]
4579 [connected]
4580 ## Start Addr = 0x00040004
wdenkc6097192002-11-03 00:24:07 +00004581
wdenk2729af92004-05-03 20:45:30 +00004582 => go 40004
4583 ## Starting application at 0x00040004 ...
4584 TIMERS=0xfff00980
4585 Using timer 1
4586 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
wdenkc6097192002-11-03 00:24:07 +00004587
wdenk2729af92004-05-03 20:45:30 +00004588Hit 'b':
4589 [q, b, e, ?] Set interval 1000000 us
4590 Enabling timer
4591Hit '?':
4592 [q, b, e, ?] ........
4593 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
4594Hit '?':
4595 [q, b, e, ?] .
4596 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
4597Hit '?':
4598 [q, b, e, ?] .
4599 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
4600Hit '?':
4601 [q, b, e, ?] .
4602 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
4603Hit 'e':
4604 [q, b, e, ?] ...Stopping timer
4605Hit 'q':
4606 [q, b, e, ?] ## Application terminated, rc = 0x0
wdenkc6097192002-11-03 00:24:07 +00004607
4608
wdenk2729af92004-05-03 20:45:30 +00004609Minicom warning:
4610================
wdenk85ec0bc2003-03-31 16:34:49 +00004611
wdenk2729af92004-05-03 20:45:30 +00004612Over time, many people have reported problems when trying to use the
4613"minicom" terminal emulation program for serial download. I (wd)
4614consider minicom to be broken, and recommend not to use it. Under
4615Unix, I recommend to use C-Kermit for general purpose use (and
4616especially for kermit binary protocol download ("loadb" command), and
Karl O. Pince53515a2012-10-01 05:11:56 +00004617use "cu" for S-Record download ("loads" command). See
4618http://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3.
4619for help with kermit.
4620
wdenk85ec0bc2003-03-31 16:34:49 +00004621
wdenk2729af92004-05-03 20:45:30 +00004622Nevertheless, if you absolutely want to use it try adding this
4623configuration to your "File transfer protocols" section:
wdenk52f52c12003-06-19 23:04:19 +00004624
wdenk2729af92004-05-03 20:45:30 +00004625 Name Program Name U/D FullScr IO-Red. Multi
4626 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
4627 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
wdenk52f52c12003-06-19 23:04:19 +00004628
4629
wdenk2729af92004-05-03 20:45:30 +00004630NetBSD Notes:
4631=============
wdenkc6097192002-11-03 00:24:07 +00004632
wdenk2729af92004-05-03 20:45:30 +00004633Starting at version 0.9.2, U-Boot supports NetBSD both as host
4634(build U-Boot) and target system (boots NetBSD/mpc8xx).
wdenkc6097192002-11-03 00:24:07 +00004635
wdenk2729af92004-05-03 20:45:30 +00004636Building requires a cross environment; it is known to work on
4637NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
4638need gmake since the Makefiles are not compatible with BSD make).
4639Note that the cross-powerpc package does not install include files;
4640attempting to build U-Boot will fail because <machine/ansi.h> is
4641missing. This file has to be installed and patched manually:
wdenkc6097192002-11-03 00:24:07 +00004642
wdenk2729af92004-05-03 20:45:30 +00004643 # cd /usr/pkg/cross/powerpc-netbsd/include
4644 # mkdir powerpc
4645 # ln -s powerpc machine
4646 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
4647 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
wdenkc6097192002-11-03 00:24:07 +00004648
wdenk2729af92004-05-03 20:45:30 +00004649Native builds *don't* work due to incompatibilities between native
4650and U-Boot include files.
wdenkc6097192002-11-03 00:24:07 +00004651
wdenk2729af92004-05-03 20:45:30 +00004652Booting assumes that (the first part of) the image booted is a
4653stage-2 loader which in turn loads and then invokes the kernel
4654proper. Loader sources will eventually appear in the NetBSD source
4655tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
wdenk2a8af182005-04-13 10:02:42 +00004656meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
wdenkc6097192002-11-03 00:24:07 +00004657
4658
wdenk2729af92004-05-03 20:45:30 +00004659Implementation Internals:
4660=========================
wdenkc6097192002-11-03 00:24:07 +00004661
wdenk2729af92004-05-03 20:45:30 +00004662The following is not intended to be a complete description of every
4663implementation detail. However, it should help to understand the
4664inner workings of U-Boot and make it easier to port it to custom
4665hardware.
wdenkc6097192002-11-03 00:24:07 +00004666
4667
wdenk2729af92004-05-03 20:45:30 +00004668Initial Stack, Global Data:
4669---------------------------
wdenkc6097192002-11-03 00:24:07 +00004670
wdenk2729af92004-05-03 20:45:30 +00004671The implementation of U-Boot is complicated by the fact that U-Boot
4672starts running out of ROM (flash memory), usually without access to
4673system RAM (because the memory controller is not initialized yet).
4674This means that we don't have writable Data or BSS segments, and BSS
4675is not initialized as zero. To be able to get a C environment working
4676at all, we have to allocate at least a minimal stack. Implementation
4677options for this are defined and restricted by the CPU used: Some CPU
4678models provide on-chip memory (like the IMMR area on MPC8xx and
4679MPC826x processors), on others (parts of) the data cache can be
4680locked as (mis-) used as memory, etc.
wdenkc6097192002-11-03 00:24:07 +00004681
Wolfgang Denk218ca722008-03-26 10:40:12 +01004682 Chris Hallinan posted a good summary of these issues to the
Wolfgang Denk06682362008-12-30 22:56:11 +01004683 U-Boot mailing list:
wdenk43d96162003-03-06 00:02:04 +00004684
wdenk2729af92004-05-03 20:45:30 +00004685 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
4686 From: "Chris Hallinan" <clh@net1plus.com>
4687 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
4688 ...
wdenk43d96162003-03-06 00:02:04 +00004689
wdenk2729af92004-05-03 20:45:30 +00004690 Correct me if I'm wrong, folks, but the way I understand it
4691 is this: Using DCACHE as initial RAM for Stack, etc, does not
4692 require any physical RAM backing up the cache. The cleverness
4693 is that the cache is being used as a temporary supply of
4694 necessary storage before the SDRAM controller is setup. It's
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02004695 beyond the scope of this list to explain the details, but you
wdenk2729af92004-05-03 20:45:30 +00004696 can see how this works by studying the cache architecture and
4697 operation in the architecture and processor-specific manuals.
wdenk43d96162003-03-06 00:02:04 +00004698
wdenk2729af92004-05-03 20:45:30 +00004699 OCM is On Chip Memory, which I believe the 405GP has 4K. It
4700 is another option for the system designer to use as an
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02004701 initial stack/RAM area prior to SDRAM being available. Either
wdenk2729af92004-05-03 20:45:30 +00004702 option should work for you. Using CS 4 should be fine if your
4703 board designers haven't used it for something that would
4704 cause you grief during the initial boot! It is frequently not
4705 used.
wdenk43d96162003-03-06 00:02:04 +00004706
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02004707 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere
wdenk2729af92004-05-03 20:45:30 +00004708 with your processor/board/system design. The default value
4709 you will find in any recent u-boot distribution in
Stefan Roese8a316c92005-08-01 16:49:12 +02004710 walnut.h should work for you. I'd set it to a value larger
wdenk2729af92004-05-03 20:45:30 +00004711 than your SDRAM module. If you have a 64MB SDRAM module, set
4712 it above 400_0000. Just make sure your board has no resources
4713 that are supposed to respond to that address! That code in
4714 start.S has been around a while and should work as is when
4715 you get the config right.
wdenk43d96162003-03-06 00:02:04 +00004716
wdenk2729af92004-05-03 20:45:30 +00004717 -Chris Hallinan
4718 DS4.COM, Inc.
wdenk43d96162003-03-06 00:02:04 +00004719
wdenk2729af92004-05-03 20:45:30 +00004720It is essential to remember this, since it has some impact on the C
4721code for the initialization procedures:
wdenkc6097192002-11-03 00:24:07 +00004722
wdenk2729af92004-05-03 20:45:30 +00004723* Initialized global data (data segment) is read-only. Do not attempt
4724 to write it.
wdenkc6097192002-11-03 00:24:07 +00004725
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08004726* Do not use any uninitialized global data (or implicitly initialized
wdenk2729af92004-05-03 20:45:30 +00004727 as zero data - BSS segment) at all - this is undefined, initiali-
4728 zation is performed later (when relocating to RAM).
wdenkc6097192002-11-03 00:24:07 +00004729
wdenk2729af92004-05-03 20:45:30 +00004730* Stack space is very limited. Avoid big data buffers or things like
4731 that.
wdenkc6097192002-11-03 00:24:07 +00004732
wdenk2729af92004-05-03 20:45:30 +00004733Having only the stack as writable memory limits means we cannot use
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08004734normal global data to share information between the code. But it
wdenk2729af92004-05-03 20:45:30 +00004735turned out that the implementation of U-Boot can be greatly
4736simplified by making a global data structure (gd_t) available to all
4737functions. We could pass a pointer to this data as argument to _all_
4738functions, but this would bloat the code. Instead we use a feature of
4739the GCC compiler (Global Register Variables) to share the data: we
4740place a pointer (gd) to the global data into a register which we
4741reserve for this purpose.
wdenkc6097192002-11-03 00:24:07 +00004742
wdenk2729af92004-05-03 20:45:30 +00004743When choosing a register for such a purpose we are restricted by the
4744relevant (E)ABI specifications for the current architecture, and by
4745GCC's implementation.
wdenkc6097192002-11-03 00:24:07 +00004746
wdenk2729af92004-05-03 20:45:30 +00004747For PowerPC, the following registers have specific use:
4748 R1: stack pointer
Wolfgang Denke7670f62008-02-14 22:43:22 +01004749 R2: reserved for system use
wdenk2729af92004-05-03 20:45:30 +00004750 R3-R4: parameter passing and return values
4751 R5-R10: parameter passing
4752 R13: small data area pointer
4753 R30: GOT pointer
4754 R31: frame pointer
wdenkc6097192002-11-03 00:24:07 +00004755
Joakim Tjernlunde6bee802010-01-19 14:41:58 +01004756 (U-Boot also uses R12 as internal GOT pointer. r12
4757 is a volatile register so r12 needs to be reset when
4758 going back and forth between asm and C)
wdenkc6097192002-11-03 00:24:07 +00004759
Wolfgang Denke7670f62008-02-14 22:43:22 +01004760 ==> U-Boot will use R2 to hold a pointer to the global data
wdenkc6097192002-11-03 00:24:07 +00004761
wdenk2729af92004-05-03 20:45:30 +00004762 Note: on PPC, we could use a static initializer (since the
4763 address of the global data structure is known at compile time),
4764 but it turned out that reserving a register results in somewhat
4765 smaller code - although the code savings are not that big (on
4766 average for all boards 752 bytes for the whole U-Boot image,
4767 624 text + 127 data).
wdenkc6097192002-11-03 00:24:07 +00004768
wdenk2729af92004-05-03 20:45:30 +00004769On ARM, the following registers are used:
wdenkc6097192002-11-03 00:24:07 +00004770
wdenk2729af92004-05-03 20:45:30 +00004771 R0: function argument word/integer result
4772 R1-R3: function argument word
Jeroen Hofstee12eba1b2013-09-21 14:04:42 +02004773 R9: platform specific
4774 R10: stack limit (used only if stack checking is enabled)
wdenk2729af92004-05-03 20:45:30 +00004775 R11: argument (frame) pointer
4776 R12: temporary workspace
4777 R13: stack pointer
4778 R14: link register
4779 R15: program counter
wdenkc6097192002-11-03 00:24:07 +00004780
Jeroen Hofstee12eba1b2013-09-21 14:04:42 +02004781 ==> U-Boot will use R9 to hold a pointer to the global data
4782
4783 Note: on ARM, only R_ARM_RELATIVE relocations are supported.
wdenkc6097192002-11-03 00:24:07 +00004784
Thomas Chou0df01fd2010-05-21 11:08:03 +08004785On Nios II, the ABI is documented here:
4786 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf
4787
4788 ==> U-Boot will use gp to hold a pointer to the global data
4789
4790 Note: on Nios II, we give "-G0" option to gcc and don't use gp
4791 to access small data sections, so gp is free.
4792
Macpaul Linafc1ce82011-10-19 20:41:11 +00004793On NDS32, the following registers are used:
4794
4795 R0-R1: argument/return
4796 R2-R5: argument
4797 R15: temporary register for assembler
4798 R16: trampoline register
4799 R28: frame pointer (FP)
4800 R29: global pointer (GP)
4801 R30: link register (LP)
4802 R31: stack pointer (SP)
4803 PC: program counter (PC)
4804
4805 ==> U-Boot will use R10 to hold a pointer to the global data
4806
Wolfgang Denkd87080b2006-03-31 18:32:53 +02004807NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
4808or current versions of GCC may "optimize" the code too much.
wdenkc6097192002-11-03 00:24:07 +00004809
Rick Chen3fafced2017-12-26 13:55:59 +08004810On RISC-V, the following registers are used:
4811
4812 x0: hard-wired zero (zero)
4813 x1: return address (ra)
4814 x2: stack pointer (sp)
4815 x3: global pointer (gp)
4816 x4: thread pointer (tp)
4817 x5: link register (t0)
4818 x8: frame pointer (fp)
4819 x10-x11: arguments/return values (a0-1)
4820 x12-x17: arguments (a2-7)
4821 x28-31: temporaries (t3-6)
4822 pc: program counter (pc)
4823
4824 ==> U-Boot will use gp to hold a pointer to the global data
4825
wdenk2729af92004-05-03 20:45:30 +00004826Memory Management:
4827------------------
wdenkc6097192002-11-03 00:24:07 +00004828
wdenk2729af92004-05-03 20:45:30 +00004829U-Boot runs in system state and uses physical addresses, i.e. the
4830MMU is not used either for address mapping nor for memory protection.
wdenkc6097192002-11-03 00:24:07 +00004831
wdenk2729af92004-05-03 20:45:30 +00004832The available memory is mapped to fixed addresses using the memory
4833controller. In this process, a contiguous block is formed for each
4834memory type (Flash, SDRAM, SRAM), even when it consists of several
4835physical memory banks.
wdenkc6097192002-11-03 00:24:07 +00004836
wdenk2729af92004-05-03 20:45:30 +00004837U-Boot is installed in the first 128 kB of the first Flash bank (on
4838TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
4839booting and sizing and initializing DRAM, the code relocates itself
4840to the upper end of DRAM. Immediately below the U-Boot code some
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02004841memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN
wdenk2729af92004-05-03 20:45:30 +00004842configuration setting]. Below that, a structure with global Board
4843Info data is placed, followed by the stack (growing downward).
wdenkc6097192002-11-03 00:24:07 +00004844
wdenk2729af92004-05-03 20:45:30 +00004845Additionally, some exception handler code is copied to the low 8 kB
4846of DRAM (0x00000000 ... 0x00001FFF).
wdenkc6097192002-11-03 00:24:07 +00004847
wdenk2729af92004-05-03 20:45:30 +00004848So a typical memory configuration with 16 MB of DRAM could look like
4849this:
wdenkc6097192002-11-03 00:24:07 +00004850
wdenk2729af92004-05-03 20:45:30 +00004851 0x0000 0000 Exception Vector code
4852 :
4853 0x0000 1FFF
4854 0x0000 2000 Free for Application Use
4855 :
4856 :
wdenkc6097192002-11-03 00:24:07 +00004857
wdenk2729af92004-05-03 20:45:30 +00004858 :
4859 :
4860 0x00FB FF20 Monitor Stack (Growing downward)
4861 0x00FB FFAC Board Info Data and permanent copy of global data
4862 0x00FC 0000 Malloc Arena
4863 :
4864 0x00FD FFFF
4865 0x00FE 0000 RAM Copy of Monitor Code
4866 ... eventually: LCD or video framebuffer
4867 ... eventually: pRAM (Protected RAM - unchanged by reset)
4868 0x00FF FFFF [End of RAM]
wdenkc6097192002-11-03 00:24:07 +00004869
4870
wdenk2729af92004-05-03 20:45:30 +00004871System Initialization:
4872----------------------
wdenkc6097192002-11-03 00:24:07 +00004873
wdenk2729af92004-05-03 20:45:30 +00004874In the reset configuration, U-Boot starts at the reset entry point
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02004875(on most PowerPC systems at address 0x00000100). Because of the reset
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08004876configuration for CS0# this is a mirror of the on board Flash memory.
wdenk2729af92004-05-03 20:45:30 +00004877To be able to re-map memory U-Boot then jumps to its link address.
4878To be able to implement the initialization code in C, a (small!)
4879initial stack is set up in the internal Dual Ported RAM (in case CPUs
Heiko Schocher2eb48ff2017-06-07 17:33:10 +02004880which provide such a feature like), or in a locked part of the data
4881cache. After that, U-Boot initializes the CPU core, the caches and
4882the SIU.
wdenkc6097192002-11-03 00:24:07 +00004883
wdenk2729af92004-05-03 20:45:30 +00004884Next, all (potentially) available memory banks are mapped using a
4885preliminary mapping. For example, we put them on 512 MB boundaries
4886(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
4887on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
4888programmed for SDRAM access. Using the temporary configuration, a
4889simple memory test is run that determines the size of the SDRAM
4890banks.
wdenkc6097192002-11-03 00:24:07 +00004891
wdenk2729af92004-05-03 20:45:30 +00004892When there is more than one SDRAM bank, and the banks are of
4893different size, the largest is mapped first. For equal size, the first
4894bank (CS2#) is mapped first. The first mapping is always for address
48950x00000000, with any additional banks following immediately to create
4896contiguous memory starting from 0.
wdenkc6097192002-11-03 00:24:07 +00004897
wdenk2729af92004-05-03 20:45:30 +00004898Then, the monitor installs itself at the upper end of the SDRAM area
4899and allocates memory for use by malloc() and for the global Board
4900Info data; also, the exception vector code is copied to the low RAM
4901pages, and the final stack is set up.
wdenkc6097192002-11-03 00:24:07 +00004902
wdenk2729af92004-05-03 20:45:30 +00004903Only after this relocation will you have a "normal" C environment;
4904until that you are restricted in several ways, mostly because you are
4905running from ROM, and because the code will have to be relocated to a
4906new address in RAM.
wdenkc6097192002-11-03 00:24:07 +00004907
4908
wdenk2729af92004-05-03 20:45:30 +00004909U-Boot Porting Guide:
4910----------------------
wdenkc6097192002-11-03 00:24:07 +00004911
wdenk2729af92004-05-03 20:45:30 +00004912[Based on messages by Jerry Van Baren in the U-Boot-Users mailing
4913list, October 2002]
wdenkc6097192002-11-03 00:24:07 +00004914
4915
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04004916int main(int argc, char *argv[])
wdenk2729af92004-05-03 20:45:30 +00004917{
4918 sighandler_t no_more_time;
wdenkc6097192002-11-03 00:24:07 +00004919
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04004920 signal(SIGALRM, no_more_time);
4921 alarm(PROJECT_DEADLINE - toSec (3 * WEEK));
wdenkc6097192002-11-03 00:24:07 +00004922
wdenk2729af92004-05-03 20:45:30 +00004923 if (available_money > available_manpower) {
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04004924 Pay consultant to port U-Boot;
wdenkc6097192002-11-03 00:24:07 +00004925 return 0;
4926 }
4927
wdenk2729af92004-05-03 20:45:30 +00004928 Download latest U-Boot source;
4929
Wolfgang Denk06682362008-12-30 22:56:11 +01004930 Subscribe to u-boot mailing list;
wdenk2729af92004-05-03 20:45:30 +00004931
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04004932 if (clueless)
4933 email("Hi, I am new to U-Boot, how do I get started?");
wdenkc6097192002-11-03 00:24:07 +00004934
wdenk2729af92004-05-03 20:45:30 +00004935 while (learning) {
4936 Read the README file in the top level directory;
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04004937 Read http://www.denx.de/twiki/bin/view/DULG/Manual;
4938 Read applicable doc/*.README;
wdenk2729af92004-05-03 20:45:30 +00004939 Read the source, Luke;
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04004940 /* find . -name "*.[chS]" | xargs grep -i <keyword> */
wdenk2729af92004-05-03 20:45:30 +00004941 }
wdenkc6097192002-11-03 00:24:07 +00004942
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04004943 if (available_money > toLocalCurrency ($2500))
4944 Buy a BDI3000;
4945 else
wdenk2729af92004-05-03 20:45:30 +00004946 Add a lot of aggravation and time;
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04004947
4948 if (a similar board exists) { /* hopefully... */
4949 cp -a board/<similar> board/<myboard>
4950 cp include/configs/<similar>.h include/configs/<myboard>.h
4951 } else {
4952 Create your own board support subdirectory;
4953 Create your own board include/configs/<myboard>.h file;
wdenk2729af92004-05-03 20:45:30 +00004954 }
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04004955 Edit new board/<myboard> files
4956 Edit new include/configs/<myboard>.h
wdenkc6097192002-11-03 00:24:07 +00004957
Jerry Van Baren6c3fef22009-07-15 20:42:59 -04004958 while (!accepted) {
4959 while (!running) {
4960 do {
4961 Add / modify source code;
4962 } until (compiles);
4963 Debug;
4964 if (clueless)
4965 email("Hi, I am having problems...");
4966 }
4967 Send patch file to the U-Boot email list;
4968 if (reasonable critiques)
4969 Incorporate improvements from email list code review;
4970 else
4971 Defend code as written;
wdenk2729af92004-05-03 20:45:30 +00004972 }
wdenkc6097192002-11-03 00:24:07 +00004973
wdenk2729af92004-05-03 20:45:30 +00004974 return 0;
4975}
4976
4977void no_more_time (int sig)
4978{
4979 hire_a_guru();
4980}
wdenkc6097192002-11-03 00:24:07 +00004981
4982
wdenk2729af92004-05-03 20:45:30 +00004983Coding Standards:
4984-----------------
wdenkc6097192002-11-03 00:24:07 +00004985
wdenk2729af92004-05-03 20:45:30 +00004986All contributions to U-Boot should conform to the Linux kernel
Baruch Siach659208d2017-12-10 17:34:35 +02004987coding style; see the kernel coding style guide at
4988https://www.kernel.org/doc/html/latest/process/coding-style.html, and the
4989script "scripts/Lindent" in your Linux kernel source directory.
wdenk2729af92004-05-03 20:45:30 +00004990
Detlev Zundel2c051652006-09-01 15:39:02 +02004991Source files originating from a different project (for example the
4992MTD subsystem) are generally exempt from these guidelines and are not
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08004993reformatted to ease subsequent migration to newer versions of those
Detlev Zundel2c051652006-09-01 15:39:02 +02004994sources.
4995
4996Please note that U-Boot is implemented in C (and to some small parts in
4997Assembler); no C++ is used, so please do not use C++ style comments (//)
4998in your code.
wdenk2729af92004-05-03 20:45:30 +00004999
5000Please also stick to the following formatting rules:
5001- remove any trailing white space
Wolfgang Denk7ca92962011-07-27 10:59:55 +00005002- use TAB characters for indentation and vertical alignment, not spaces
wdenk2729af92004-05-03 20:45:30 +00005003- make sure NOT to use DOS '\r\n' line feeds
Wolfgang Denk7ca92962011-07-27 10:59:55 +00005004- do not add more than 2 consecutive empty lines to source files
wdenk2729af92004-05-03 20:45:30 +00005005- do not add trailing empty lines to source files
5006
5007Submissions which do not conform to the standards may be returned
5008with a request to reformat the changes.
wdenkc6097192002-11-03 00:24:07 +00005009
5010
wdenk2729af92004-05-03 20:45:30 +00005011Submitting Patches:
5012-------------------
wdenkc6097192002-11-03 00:24:07 +00005013
wdenk2729af92004-05-03 20:45:30 +00005014Since the number of patches for U-Boot is growing, we need to
5015establish some rules. Submissions which do not conform to these rules
5016may be rejected, even when they contain important and valuable stuff.
wdenkc6097192002-11-03 00:24:07 +00005017
Magnus Lilja0d28f342008-08-06 19:32:33 +02005018Please see http://www.denx.de/wiki/U-Boot/Patches for details.
Wolfgang Denk218ca722008-03-26 10:40:12 +01005019
Wolfgang Denk06682362008-12-30 22:56:11 +01005020Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>;
S. Lockwood-Childs1dade182017-11-14 22:56:42 -08005021see https://lists.denx.de/listinfo/u-boot
Wolfgang Denk06682362008-12-30 22:56:11 +01005022
wdenk2729af92004-05-03 20:45:30 +00005023When you send a patch, please include the following information with
5024it:
wdenkc6097192002-11-03 00:24:07 +00005025
wdenk2729af92004-05-03 20:45:30 +00005026* For bug fixes: a description of the bug and how your patch fixes
5027 this bug. Please try to include a way of demonstrating that the
5028 patch actually fixes something.
wdenkc6097192002-11-03 00:24:07 +00005029
wdenk2729af92004-05-03 20:45:30 +00005030* For new features: a description of the feature and your
5031 implementation.
wdenkc6097192002-11-03 00:24:07 +00005032
wdenk2729af92004-05-03 20:45:30 +00005033* A CHANGELOG entry as plaintext (separate from the patch)
5034
Robert P. J. Day7207b362015-12-19 07:16:10 -05005035* For major contributions, add a MAINTAINERS file with your
5036 information and associated file and directory references.
wdenk2729af92004-05-03 20:45:30 +00005037
Albert ARIBAUD27af9302013-09-11 15:52:51 +02005038* When you add support for a new board, don't forget to add a
5039 maintainer e-mail address to the boards.cfg file, too.
wdenk2729af92004-05-03 20:45:30 +00005040
5041* If your patch adds new configuration options, don't forget to
5042 document these in the README file.
5043
Wolfgang Denk218ca722008-03-26 10:40:12 +01005044* The patch itself. If you are using git (which is *strongly*
5045 recommended) you can easily generate the patch using the
Wolfgang Denk7ca92962011-07-27 10:59:55 +00005046 "git format-patch". If you then use "git send-email" to send it to
Wolfgang Denk218ca722008-03-26 10:40:12 +01005047 the U-Boot mailing list, you will avoid most of the common problems
5048 with some other mail clients.
wdenk2729af92004-05-03 20:45:30 +00005049
Wolfgang Denk218ca722008-03-26 10:40:12 +01005050 If you cannot use git, use "diff -purN OLD NEW". If your version of
5051 diff does not support these options, then get the latest version of
5052 GNU diff.
wdenk2729af92004-05-03 20:45:30 +00005053
Wolfgang Denk218ca722008-03-26 10:40:12 +01005054 The current directory when running this command shall be the parent
5055 directory of the U-Boot source tree (i. e. please make sure that
5056 your patch includes sufficient directory information for the
5057 affected files).
5058
5059 We prefer patches as plain text. MIME attachments are discouraged,
5060 and compressed attachments must not be used.
wdenk2729af92004-05-03 20:45:30 +00005061
5062* If one logical set of modifications affects or creates several
5063 files, all these changes shall be submitted in a SINGLE patch file.
5064
5065* Changesets that contain different, unrelated modifications shall be
5066 submitted as SEPARATE patches, one patch per changeset.
5067
5068
5069Notes:
5070
Simon Glass6de80f22016-07-27 20:33:08 -06005071* Before sending the patch, run the buildman script on your patched
wdenk2729af92004-05-03 20:45:30 +00005072 source tree and make sure that no errors or warnings are reported
5073 for any of the boards.
5074
5075* Keep your modifications to the necessary minimum: A patch
5076 containing several unrelated changes or arbitrary reformats will be
5077 returned with a request to re-formatting / split it.
5078
5079* If you modify existing code, make sure that your new code does not
5080 add to the memory footprint of the code ;-) Small is beautiful!
5081 When adding new features, these should compile conditionally only
5082 (using #ifdef), and the resulting code with the new feature
5083 disabled must not need more memory than the old code without your
5084 modification.
wdenk90dc6702005-05-03 14:12:25 +00005085
Wolfgang Denk06682362008-12-30 22:56:11 +01005086* Remember that there is a size limit of 100 kB per message on the
5087 u-boot mailing list. Bigger patches will be moderated. If they are
5088 reasonable and not too big, they will be acknowledged. But patches
5089 bigger than the size limit should be avoided.