1 #
2 # (C) Copyright 2000 - 2012
3 # Wolfgang Denk, DENX Software Engineering, wd@denx.de.
4 #
5 # See file CREDITS for list of people who contributed to this
6 # project.
7 #
8 # This program is free software; you can redistribute it and/or
9 # modify it under the terms of the GNU General Public License as
10 # published by the Free Software Foundation; either version 2 of
11 # the License, or (at your option) any later version.
12 #
13 # This program is distributed in the hope that it will be useful,
14 # but WITHOUT ANY WARRANTY; without even the implied warranty of
15 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 # GNU General Public License for more details.
17 #
18 # You should have received a copy of the GNU General Public License
19 # along with this program; if not, write to the Free Software
20 # Foundation, Inc., 59 Temple Place, Suite 330, Boston,
21 # MA 02111-1307 USA
22 #
24 Summary:
25 ========
27 This directory contains the source code for U-Boot, a boot loader for
28 Embedded boards based on PowerPC, ARM, MIPS and several other
29 processors, which can be installed in a boot ROM and used to
30 initialize and test the hardware or to download and run application
31 code.
33 The development of U-Boot is closely related to Linux: some parts of
34 the source code originate in the Linux source tree, we have some
35 header files in common, and special provision has been made to
36 support booting of Linux images.
38 Some attention has been paid to make this software easily
39 configurable and extendable. For instance, all monitor commands are
40 implemented with the same call interface, so that it's very easy to
41 add new commands. Also, instead of permanently adding rarely used
42 code (for instance hardware test utilities) to the monitor, you can
43 load and run it dynamically.
46 Status:
47 =======
49 In general, all boards for which a configuration option exists in the
50 Makefile have been tested to some extent and can be considered
51 "working". In fact, many of them are used in production systems.
53 In case of problems see the CHANGELOG and CREDITS files to find out
54 who contributed the specific port. The MAINTAINERS file lists board
55 maintainers.
58 Where to get help:
59 ==================
61 In case you have questions about, problems with or contributions for
62 U-Boot you should send a message to the U-Boot mailing list at
63 <u-boot@lists.denx.de>. There is also an archive of previous traffic
64 on the mailing list - please search the archive before asking FAQ's.
65 Please see http://lists.denx.de/pipermail/u-boot and
66 http://dir.gmane.org/gmane.comp.boot-loaders.u-boot
69 Where to get source code:
70 =========================
72 The U-Boot source code is maintained in the git repository at
73 git://www.denx.de/git/u-boot.git ; you can browse it online at
74 http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary
76 The "snapshot" links on this page allow you to download tarballs of
77 any version you might be interested in. Official releases are also
78 available for FTP download from the ftp://ftp.denx.de/pub/u-boot/
79 directory.
81 Pre-built (and tested) images are available from
82 ftp://ftp.denx.de/pub/u-boot/images/
85 Where we come from:
86 ===================
88 - start from 8xxrom sources
89 - create PPCBoot project (http://sourceforge.net/projects/ppcboot)
90 - clean up code
91 - make it easier to add custom boards
92 - make it possible to add other [PowerPC] CPUs
93 - extend functions, especially:
94 * Provide extended interface to Linux boot loader
95 * S-Record download
96 * network boot
97 * PCMCIA / CompactFlash / ATA disk / SCSI ... boot
98 - create ARMBoot project (http://sourceforge.net/projects/armboot)
99 - add other CPU families (starting with ARM)
100 - create U-Boot project (http://sourceforge.net/projects/u-boot)
101 - current project page: see http://www.denx.de/wiki/U-Boot
104 Names and Spelling:
105 ===================
107 The "official" name of this project is "Das U-Boot". The spelling
108 "U-Boot" shall be used in all written text (documentation, comments
109 in source files etc.). Example:
111 This is the README file for the U-Boot project.
113 File names etc. shall be based on the string "u-boot". Examples:
115 include/asm-ppc/u-boot.h
117 #include <asm/u-boot.h>
119 Variable names, preprocessor constants etc. shall be either based on
120 the string "u_boot" or on "U_BOOT". Example:
122 U_BOOT_VERSION u_boot_logo
123 IH_OS_U_BOOT u_boot_hush_start
126 Versioning:
127 ===========
129 Starting with the release in October 2008, the names of the releases
130 were changed from numerical release numbers without deeper meaning
131 into a time stamp based numbering. Regular releases are identified by
132 names consisting of the calendar year and month of the release date.
133 Additional fields (if present) indicate release candidates or bug fix
134 releases in "stable" maintenance trees.
136 Examples:
137 U-Boot v2009.11 - Release November 2009
138 U-Boot v2009.11.1 - Release 1 in version November 2009 stable tree
139 U-Boot v2010.09-rc1 - Release candiate 1 for September 2010 release
142 Directory Hierarchy:
143 ====================
145 /arch Architecture specific files
146 /arm Files generic to ARM architecture
147 /cpu CPU specific files
148 /arm720t Files specific to ARM 720 CPUs
149 /arm920t Files specific to ARM 920 CPUs
150 /at91 Files specific to Atmel AT91RM9200 CPU
151 /imx Files specific to Freescale MC9328 i.MX CPUs
152 /s3c24x0 Files specific to Samsung S3C24X0 CPUs
153 /arm925t Files specific to ARM 925 CPUs
154 /arm926ejs Files specific to ARM 926 CPUs
155 /arm1136 Files specific to ARM 1136 CPUs
156 /ixp Files specific to Intel XScale IXP CPUs
157 /pxa Files specific to Intel XScale PXA CPUs
158 /s3c44b0 Files specific to Samsung S3C44B0 CPUs
159 /sa1100 Files specific to Intel StrongARM SA1100 CPUs
160 /lib Architecture specific library files
161 /avr32 Files generic to AVR32 architecture
162 /cpu CPU specific files
163 /lib Architecture specific library files
164 /blackfin Files generic to Analog Devices Blackfin architecture
165 /cpu CPU specific files
166 /lib Architecture specific library files
167 /x86 Files generic to x86 architecture
168 /cpu CPU specific files
169 /lib Architecture specific library files
170 /m68k Files generic to m68k architecture
171 /cpu CPU specific files
172 /mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs
173 /mcf5227x Files specific to Freescale ColdFire MCF5227x CPUs
174 /mcf532x Files specific to Freescale ColdFire MCF5329 CPUs
175 /mcf5445x Files specific to Freescale ColdFire MCF5445x CPUs
176 /mcf547x_8x Files specific to Freescale ColdFire MCF547x_8x CPUs
177 /lib Architecture specific library files
178 /microblaze Files generic to microblaze architecture
179 /cpu CPU specific files
180 /lib Architecture specific library files
181 /mips Files generic to MIPS architecture
182 /cpu CPU specific files
183 /mips32 Files specific to MIPS32 CPUs
184 /xburst Files specific to Ingenic XBurst CPUs
185 /lib Architecture specific library files
186 /nds32 Files generic to NDS32 architecture
187 /cpu CPU specific files
188 /n1213 Files specific to Andes Technology N1213 CPUs
189 /lib Architecture specific library files
190 /nios2 Files generic to Altera NIOS2 architecture
191 /cpu CPU specific files
192 /lib Architecture specific library files
193 /powerpc Files generic to PowerPC architecture
194 /cpu CPU specific files
195 /74xx_7xx Files specific to Freescale MPC74xx and 7xx CPUs
196 /mpc5xx Files specific to Freescale MPC5xx CPUs
197 /mpc5xxx Files specific to Freescale MPC5xxx CPUs
198 /mpc8xx Files specific to Freescale MPC8xx CPUs
199 /mpc8220 Files specific to Freescale MPC8220 CPUs
200 /mpc824x Files specific to Freescale MPC824x CPUs
201 /mpc8260 Files specific to Freescale MPC8260 CPUs
202 /mpc85xx Files specific to Freescale MPC85xx CPUs
203 /ppc4xx Files specific to AMCC PowerPC 4xx CPUs
204 /lib Architecture specific library files
205 /sh Files generic to SH architecture
206 /cpu CPU specific files
207 /sh2 Files specific to sh2 CPUs
208 /sh3 Files specific to sh3 CPUs
209 /sh4 Files specific to sh4 CPUs
210 /lib Architecture specific library files
211 /sparc Files generic to SPARC architecture
212 /cpu CPU specific files
213 /leon2 Files specific to Gaisler LEON2 SPARC CPU
214 /leon3 Files specific to Gaisler LEON3 SPARC CPU
215 /lib Architecture specific library files
216 /api Machine/arch independent API for external apps
217 /board Board dependent files
218 /common Misc architecture independent functions
219 /disk Code for disk drive partition handling
220 /doc Documentation (don't expect too much)
221 /drivers Commonly used device drivers
222 /examples Example code for standalone applications, etc.
223 /fs Filesystem code (cramfs, ext2, jffs2, etc.)
224 /include Header Files
225 /lib Files generic to all architectures
226 /libfdt Library files to support flattened device trees
227 /lzma Library files to support LZMA decompression
228 /lzo Library files to support LZO decompression
229 /net Networking code
230 /post Power On Self Test
231 /rtc Real Time Clock drivers
232 /tools Tools to build S-Record or U-Boot images, etc.
234 Software Configuration:
235 =======================
237 Configuration is usually done using C preprocessor defines; the
238 rationale behind that is to avoid dead code whenever possible.
240 There are two classes of configuration variables:
242 * Configuration _OPTIONS_:
243 These are selectable by the user and have names beginning with
244 "CONFIG_".
246 * Configuration _SETTINGS_:
247 These depend on the hardware etc. and should not be meddled with if
248 you don't know what you're doing; they have names beginning with
249 "CONFIG_SYS_".
251 Later we will add a configuration tool - probably similar to or even
252 identical to what's used for the Linux kernel. Right now, we have to
253 do the configuration by hand, which means creating some symbolic
254 links and editing some configuration files. We use the TQM8xxL boards
255 as an example here.
258 Selection of Processor Architecture and Board Type:
259 ---------------------------------------------------
261 For all supported boards there are ready-to-use default
262 configurations available; just type "make <board_name>_config".
264 Example: For a TQM823L module type:
266 cd u-boot
267 make TQM823L_config
269 For the Cogent platform, you need to specify the CPU type as well;
270 e.g. "make cogent_mpc8xx_config". And also configure the cogent
271 directory according to the instructions in cogent/README.
274 Configuration Options:
275 ----------------------
277 Configuration depends on the combination of board and CPU type; all
278 such information is kept in a configuration file
279 "include/configs/<board_name>.h".
281 Example: For a TQM823L module, all configuration settings are in
282 "include/configs/TQM823L.h".
285 Many of the options are named exactly as the corresponding Linux
286 kernel configuration options. The intention is to make it easier to
287 build a config tool - later.
290 The following options need to be configured:
292 - CPU Type: Define exactly one, e.g. CONFIG_MPC85XX.
294 - Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS.
296 - CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined)
297 Define exactly one, e.g. CONFIG_ATSTK1002
299 - CPU Module Type: (if CONFIG_COGENT is defined)
300 Define exactly one of
301 CONFIG_CMA286_60_OLD
302 --- FIXME --- not tested yet:
303 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P,
304 CONFIG_CMA287_23, CONFIG_CMA287_50
306 - Motherboard Type: (if CONFIG_COGENT is defined)
307 Define exactly one of
308 CONFIG_CMA101, CONFIG_CMA102
310 - Motherboard I/O Modules: (if CONFIG_COGENT is defined)
311 Define one or more of
312 CONFIG_CMA302
314 - Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined)
315 Define one or more of
316 CONFIG_LCD_HEARTBEAT - update a character position on
317 the LCD display every second with
318 a "rotator" |\-/|\-/
320 - Board flavour: (if CONFIG_MPC8260ADS is defined)
321 CONFIG_ADSTYPE
322 Possible values are:
323 CONFIG_SYS_8260ADS - original MPC8260ADS
324 CONFIG_SYS_8266ADS - MPC8266ADS
325 CONFIG_SYS_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR
326 CONFIG_SYS_8272ADS - MPC8272ADS
328 - Marvell Family Member
329 CONFIG_SYS_MVFS - define it if you want to enable
330 multiple fs option at one time
331 for marvell soc family
333 - MPC824X Family Member (if CONFIG_MPC824X is defined)
334 Define exactly one of
335 CONFIG_MPC8240, CONFIG_MPC8245
337 - 8xx CPU Options: (if using an MPC8xx CPU)
338 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if
339 get_gclk_freq() cannot work
340 e.g. if there is no 32KHz
341 reference PIT/RTC clock
342 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK
343 or XTAL/EXTAL)
345 - 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU):
346 CONFIG_SYS_8xx_CPUCLK_MIN
347 CONFIG_SYS_8xx_CPUCLK_MAX
348 CONFIG_8xx_CPUCLK_DEFAULT
349 See doc/README.MPC866
351 CONFIG_SYS_MEASURE_CPUCLK
353 Define this to measure the actual CPU clock instead
354 of relying on the correctness of the configured
355 values. Mostly useful for board bringup to make sure
356 the PLL is locked at the intended frequency. Note
357 that this requires a (stable) reference clock (32 kHz
358 RTC clock or CONFIG_SYS_8XX_XIN)
360 CONFIG_SYS_DELAYED_ICACHE
362 Define this option if you want to enable the
363 ICache only when Code runs from RAM.
365 - 85xx CPU Options:
366 CONFIG_SYS_FSL_TBCLK_DIV
368 Defines the core time base clock divider ratio compared to the
369 system clock. On most PQ3 devices this is 8, on newer QorIQ
370 devices it can be 16 or 32. The ratio varies from SoC to Soc.
372 CONFIG_SYS_FSL_PCIE_COMPAT
374 Defines the string to utilize when trying to match PCIe device
375 tree nodes for the given platform.
377 - Intel Monahans options:
378 CONFIG_SYS_MONAHANS_RUN_MODE_OSC_RATIO
380 Defines the Monahans run mode to oscillator
381 ratio. Valid values are 8, 16, 24, 31. The core
382 frequency is this value multiplied by 13 MHz.
384 CONFIG_SYS_MONAHANS_TURBO_RUN_MODE_RATIO
386 Defines the Monahans turbo mode to oscillator
387 ratio. Valid values are 1 (default if undefined) and
388 2. The core frequency as calculated above is multiplied
389 by this value.
391 - MIPS CPU options:
392 CONFIG_SYS_INIT_SP_OFFSET
394 Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack
395 pointer. This is needed for the temporary stack before
396 relocation.
398 CONFIG_SYS_MIPS_CACHE_MODE
400 Cache operation mode for the MIPS CPU.
401 See also arch/mips/include/asm/mipsregs.h.
402 Possible values are:
403 CONF_CM_CACHABLE_NO_WA
404 CONF_CM_CACHABLE_WA
405 CONF_CM_UNCACHED
406 CONF_CM_CACHABLE_NONCOHERENT
407 CONF_CM_CACHABLE_CE
408 CONF_CM_CACHABLE_COW
409 CONF_CM_CACHABLE_CUW
410 CONF_CM_CACHABLE_ACCELERATED
412 CONFIG_SYS_XWAY_EBU_BOOTCFG
414 Special option for Lantiq XWAY SoCs for booting from NOR flash.
415 See also arch/mips/cpu/mips32/start.S.
417 CONFIG_XWAY_SWAP_BYTES
419 Enable compilation of tools/xway-swap-bytes needed for Lantiq
420 XWAY SoCs for booting from NOR flash. The U-Boot image needs to
421 be swapped if a flash programmer is used.
423 - ARM options:
424 CONFIG_SYS_EXCEPTION_VECTORS_HIGH
426 Select high exception vectors of the ARM core, e.g., do not
427 clear the V bit of the c1 register of CP15.
429 - Linux Kernel Interface:
430 CONFIG_CLOCKS_IN_MHZ
432 U-Boot stores all clock information in Hz
433 internally. For binary compatibility with older Linux
434 kernels (which expect the clocks passed in the
435 bd_info data to be in MHz) the environment variable
436 "clocks_in_mhz" can be defined so that U-Boot
437 converts clock data to MHZ before passing it to the
438 Linux kernel.
439 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
440 "clocks_in_mhz=1" is automatically included in the
441 default environment.
443 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
445 When transferring memsize parameter to linux, some versions
446 expect it to be in bytes, others in MB.
447 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
449 CONFIG_OF_LIBFDT
451 New kernel versions are expecting firmware settings to be
452 passed using flattened device trees (based on open firmware
453 concepts).
455 CONFIG_OF_LIBFDT
456 * New libfdt-based support
457 * Adds the "fdt" command
458 * The bootm command automatically updates the fdt
460 OF_CPU - The proper name of the cpus node (only required for
461 MPC512X and MPC5xxx based boards).
462 OF_SOC - The proper name of the soc node (only required for
463 MPC512X and MPC5xxx based boards).
464 OF_TBCLK - The timebase frequency.
465 OF_STDOUT_PATH - The path to the console device
467 boards with QUICC Engines require OF_QE to set UCC MAC
468 addresses
470 CONFIG_OF_BOARD_SETUP
472 Board code has addition modification that it wants to make
473 to the flat device tree before handing it off to the kernel
475 CONFIG_OF_BOOT_CPU
477 This define fills in the correct boot CPU in the boot
478 param header, the default value is zero if undefined.
480 CONFIG_OF_IDE_FIXUP
482 U-Boot can detect if an IDE device is present or not.
483 If not, and this new config option is activated, U-Boot
484 removes the ATA node from the DTS before booting Linux,
485 so the Linux IDE driver does not probe the device and
486 crash. This is needed for buggy hardware (uc101) where
487 no pull down resistor is connected to the signal IDE5V_DD7.
489 CONFIG_MACH_TYPE [relevant for ARM only][mandatory]
491 This setting is mandatory for all boards that have only one
492 machine type and must be used to specify the machine type
493 number as it appears in the ARM machine registry
494 (see http://www.arm.linux.org.uk/developer/machines/).
495 Only boards that have multiple machine types supported
496 in a single configuration file and the machine type is
497 runtime discoverable, do not have to use this setting.
499 - vxWorks boot parameters:
501 bootvx constructs a valid bootline using the following
502 environments variables: bootfile, ipaddr, serverip, hostname.
503 It loads the vxWorks image pointed bootfile.
505 CONFIG_SYS_VXWORKS_BOOT_DEVICE - The vxworks device name
506 CONFIG_SYS_VXWORKS_MAC_PTR - Ethernet 6 byte MA -address
507 CONFIG_SYS_VXWORKS_SERVERNAME - Name of the server
508 CONFIG_SYS_VXWORKS_BOOT_ADDR - Address of boot parameters
510 CONFIG_SYS_VXWORKS_ADD_PARAMS
512 Add it at the end of the bootline. E.g "u=username pw=secret"
514 Note: If a "bootargs" environment is defined, it will overwride
515 the defaults discussed just above.
517 - Cache Configuration:
518 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot
519 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot
520 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot
522 - Cache Configuration for ARM:
523 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache
524 controller
525 CONFIG_SYS_PL310_BASE - Physical base address of PL310
526 controller register space
528 - Serial Ports:
529 CONFIG_PL010_SERIAL
531 Define this if you want support for Amba PrimeCell PL010 UARTs.
533 CONFIG_PL011_SERIAL
535 Define this if you want support for Amba PrimeCell PL011 UARTs.
537 CONFIG_PL011_CLOCK
539 If you have Amba PrimeCell PL011 UARTs, set this variable to
540 the clock speed of the UARTs.
542 CONFIG_PL01x_PORTS
544 If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
545 define this to a list of base addresses for each (supported)
546 port. See e.g. include/configs/versatile.h
548 CONFIG_PL011_SERIAL_RLCR
550 Some vendor versions of PL011 serial ports (e.g. ST-Ericsson U8500)
551 have separate receive and transmit line control registers. Set
552 this variable to initialize the extra register.
554 CONFIG_PL011_SERIAL_FLUSH_ON_INIT
556 On some platforms (e.g. U8500) U-Boot is loaded by a second stage
557 boot loader that has already initialized the UART. Define this
558 variable to flush the UART at init time.
561 - Console Interface:
562 Depending on board, define exactly one serial port
563 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
564 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial
565 console by defining CONFIG_8xx_CONS_NONE
567 Note: if CONFIG_8xx_CONS_NONE is defined, the serial
568 port routines must be defined elsewhere
569 (i.e. serial_init(), serial_getc(), ...)
571 CONFIG_CFB_CONSOLE
572 Enables console device for a color framebuffer. Needs following
573 defines (cf. smiLynxEM, i8042)
574 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation
575 (default big endian)
576 VIDEO_HW_RECTFILL graphic chip supports
577 rectangle fill
578 (cf. smiLynxEM)
579 VIDEO_HW_BITBLT graphic chip supports
580 bit-blit (cf. smiLynxEM)
581 VIDEO_VISIBLE_COLS visible pixel columns
582 (cols=pitch)
583 VIDEO_VISIBLE_ROWS visible pixel rows
584 VIDEO_PIXEL_SIZE bytes per pixel
585 VIDEO_DATA_FORMAT graphic data format
586 (0-5, cf. cfb_console.c)
587 VIDEO_FB_ADRS framebuffer address
588 VIDEO_KBD_INIT_FCT keyboard int fct
589 (i.e. i8042_kbd_init())
590 VIDEO_TSTC_FCT test char fct
591 (i.e. i8042_tstc)
592 VIDEO_GETC_FCT get char fct
593 (i.e. i8042_getc)
594 CONFIG_CONSOLE_CURSOR cursor drawing on/off
595 (requires blink timer
596 cf. i8042.c)
597 CONFIG_SYS_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c)
598 CONFIG_CONSOLE_TIME display time/date info in
599 upper right corner
600 (requires CONFIG_CMD_DATE)
601 CONFIG_VIDEO_LOGO display Linux logo in
602 upper left corner
603 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of
604 linux_logo.h for logo.
605 Requires CONFIG_VIDEO_LOGO
606 CONFIG_CONSOLE_EXTRA_INFO
607 additional board info beside
608 the logo
610 When CONFIG_CFB_CONSOLE is defined, video console is
611 default i/o. Serial console can be forced with
612 environment 'console=serial'.
614 When CONFIG_SILENT_CONSOLE is defined, all console
615 messages (by U-Boot and Linux!) can be silenced with
616 the "silent" environment variable. See
617 doc/README.silent for more information.
619 - Console Baudrate:
620 CONFIG_BAUDRATE - in bps
621 Select one of the baudrates listed in
622 CONFIG_SYS_BAUDRATE_TABLE, see below.
623 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale
625 - Console Rx buffer length
626 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define
627 the maximum receive buffer length for the SMC.
628 This option is actual only for 82xx and 8xx possible.
629 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE
630 must be defined, to setup the maximum idle timeout for
631 the SMC.
633 - Pre-Console Buffer:
634 Prior to the console being initialised (i.e. serial UART
635 initialised etc) all console output is silently discarded.
636 Defining CONFIG_PRE_CONSOLE_BUFFER will cause U-Boot to
637 buffer any console messages prior to the console being
638 initialised to a buffer of size CONFIG_PRE_CON_BUF_SZ
639 bytes located at CONFIG_PRE_CON_BUF_ADDR. The buffer is
640 a circular buffer, so if more than CONFIG_PRE_CON_BUF_SZ
641 bytes are output before the console is initialised, the
642 earlier bytes are discarded.
644 'Sane' compilers will generate smaller code if
645 CONFIG_PRE_CON_BUF_SZ is a power of 2
647 - Safe printf() functions
648 Define CONFIG_SYS_VSNPRINTF to compile in safe versions of
649 the printf() functions. These are defined in
650 include/vsprintf.h and include snprintf(), vsnprintf() and
651 so on. Code size increase is approximately 300-500 bytes.
652 If this option is not given then these functions will
653 silently discard their buffer size argument - this means
654 you are not getting any overflow checking in this case.
656 - Boot Delay: CONFIG_BOOTDELAY - in seconds
657 Delay before automatically booting the default image;
658 set to -1 to disable autoboot.
660 See doc/README.autoboot for these options that
661 work with CONFIG_BOOTDELAY. None are required.
662 CONFIG_BOOT_RETRY_TIME
663 CONFIG_BOOT_RETRY_MIN
664 CONFIG_AUTOBOOT_KEYED
665 CONFIG_AUTOBOOT_PROMPT
666 CONFIG_AUTOBOOT_DELAY_STR
667 CONFIG_AUTOBOOT_STOP_STR
668 CONFIG_AUTOBOOT_DELAY_STR2
669 CONFIG_AUTOBOOT_STOP_STR2
670 CONFIG_ZERO_BOOTDELAY_CHECK
671 CONFIG_RESET_TO_RETRY
673 - Autoboot Command:
674 CONFIG_BOOTCOMMAND
675 Only needed when CONFIG_BOOTDELAY is enabled;
676 define a command string that is automatically executed
677 when no character is read on the console interface
678 within "Boot Delay" after reset.
680 CONFIG_BOOTARGS
681 This can be used to pass arguments to the bootm
682 command. The value of CONFIG_BOOTARGS goes into the
683 environment value "bootargs".
685 CONFIG_RAMBOOT and CONFIG_NFSBOOT
686 The value of these goes into the environment as
687 "ramboot" and "nfsboot" respectively, and can be used
688 as a convenience, when switching between booting from
689 RAM and NFS.
691 - Pre-Boot Commands:
692 CONFIG_PREBOOT
694 When this option is #defined, the existence of the
695 environment variable "preboot" will be checked
696 immediately before starting the CONFIG_BOOTDELAY
697 countdown and/or running the auto-boot command resp.
698 entering interactive mode.
700 This feature is especially useful when "preboot" is
701 automatically generated or modified. For an example
702 see the LWMON board specific code: here "preboot" is
703 modified when the user holds down a certain
704 combination of keys on the (special) keyboard when
705 booting the systems
707 - Serial Download Echo Mode:
708 CONFIG_LOADS_ECHO
709 If defined to 1, all characters received during a
710 serial download (using the "loads" command) are
711 echoed back. This might be needed by some terminal
712 emulations (like "cu"), but may as well just take
713 time on others. This setting #define's the initial
714 value of the "loads_echo" environment variable.
716 - Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined)
717 CONFIG_KGDB_BAUDRATE
718 Select one of the baudrates listed in
719 CONFIG_SYS_BAUDRATE_TABLE, see below.
721 - Monitor Functions:
722 Monitor commands can be included or excluded
723 from the build by using the #include files
724 "config_cmd_all.h" and #undef'ing unwanted
725 commands, or using "config_cmd_default.h"
726 and augmenting with additional #define's
727 for wanted commands.
729 The default command configuration includes all commands
730 except those marked below with a "*".
732 CONFIG_CMD_ASKENV * ask for env variable
733 CONFIG_CMD_BDI bdinfo
734 CONFIG_CMD_BEDBUG * Include BedBug Debugger
735 CONFIG_CMD_BMP * BMP support
736 CONFIG_CMD_BSP * Board specific commands
737 CONFIG_CMD_BOOTD bootd
738 CONFIG_CMD_CACHE * icache, dcache
739 CONFIG_CMD_CONSOLE coninfo
740 CONFIG_CMD_CRC32 * crc32
741 CONFIG_CMD_DATE * support for RTC, date/time...
742 CONFIG_CMD_DHCP * DHCP support
743 CONFIG_CMD_DIAG * Diagnostics
744 CONFIG_CMD_DS4510 * ds4510 I2C gpio commands
745 CONFIG_CMD_DS4510_INFO * ds4510 I2C info command
746 CONFIG_CMD_DS4510_MEM * ds4510 I2C eeprom/sram commansd
747 CONFIG_CMD_DS4510_RST * ds4510 I2C rst command
748 CONFIG_CMD_DTT * Digital Therm and Thermostat
749 CONFIG_CMD_ECHO echo arguments
750 CONFIG_CMD_EDITENV edit env variable
751 CONFIG_CMD_EEPROM * EEPROM read/write support
752 CONFIG_CMD_ELF * bootelf, bootvx
753 CONFIG_CMD_EXPORTENV * export the environment
754 CONFIG_CMD_SAVEENV saveenv
755 CONFIG_CMD_FDC * Floppy Disk Support
756 CONFIG_CMD_FAT * FAT partition support
757 CONFIG_CMD_FDOS * Dos diskette Support
758 CONFIG_CMD_FLASH flinfo, erase, protect
759 CONFIG_CMD_FPGA FPGA device initialization support
760 CONFIG_CMD_GO * the 'go' command (exec code)
761 CONFIG_CMD_GREPENV * search environment
762 CONFIG_CMD_HWFLOW * RTS/CTS hw flow control
763 CONFIG_CMD_I2C * I2C serial bus support
764 CONFIG_CMD_IDE * IDE harddisk support
765 CONFIG_CMD_IMI iminfo
766 CONFIG_CMD_IMLS List all found images
767 CONFIG_CMD_IMMAP * IMMR dump support
768 CONFIG_CMD_IMPORTENV * import an environment
769 CONFIG_CMD_IRQ * irqinfo
770 CONFIG_CMD_ITEST Integer/string test of 2 values
771 CONFIG_CMD_JFFS2 * JFFS2 Support
772 CONFIG_CMD_KGDB * kgdb
773 CONFIG_CMD_LDRINFO ldrinfo (display Blackfin loader)
774 CONFIG_CMD_LOADB loadb
775 CONFIG_CMD_LOADS loads
776 CONFIG_CMD_MD5SUM print md5 message digest
777 (requires CONFIG_CMD_MEMORY and CONFIG_MD5)
778 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base,
779 loop, loopw, mtest
780 CONFIG_CMD_MISC Misc functions like sleep etc
781 CONFIG_CMD_MMC * MMC memory mapped support
782 CONFIG_CMD_MII * MII utility commands
783 CONFIG_CMD_MTDPARTS * MTD partition support
784 CONFIG_CMD_NAND * NAND support
785 CONFIG_CMD_NET bootp, tftpboot, rarpboot
786 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands
787 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command
788 CONFIG_CMD_PCI * pciinfo
789 CONFIG_CMD_PCMCIA * PCMCIA support
790 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network
791 host
792 CONFIG_CMD_PORTIO * Port I/O
793 CONFIG_CMD_REGINFO * Register dump
794 CONFIG_CMD_RUN run command in env variable
795 CONFIG_CMD_SAVES * save S record dump
796 CONFIG_CMD_SCSI * SCSI Support
797 CONFIG_CMD_SDRAM * print SDRAM configuration information
798 (requires CONFIG_CMD_I2C)
799 CONFIG_CMD_SETGETDCR Support for DCR Register access
800 (4xx only)
801 CONFIG_CMD_SF * Read/write/erase SPI NOR flash
802 CONFIG_CMD_SHA1SUM print sha1 memory digest
803 (requires CONFIG_CMD_MEMORY)
804 CONFIG_CMD_SOURCE "source" command Support
805 CONFIG_CMD_SPI * SPI serial bus support
806 CONFIG_CMD_TFTPSRV * TFTP transfer in server mode
807 CONFIG_CMD_TFTPPUT * TFTP put command (upload)
808 CONFIG_CMD_TIME * run command and report execution time
809 CONFIG_CMD_USB * USB support
810 CONFIG_CMD_CDP * Cisco Discover Protocol support
811 CONFIG_CMD_FSL * Microblaze FSL support
814 EXAMPLE: If you want all functions except of network
815 support you can write:
817 #include "config_cmd_all.h"
818 #undef CONFIG_CMD_NET
820 Other Commands:
821 fdt (flattened device tree) command: CONFIG_OF_LIBFDT
823 Note: Don't enable the "icache" and "dcache" commands
824 (configuration option CONFIG_CMD_CACHE) unless you know
825 what you (and your U-Boot users) are doing. Data
826 cache cannot be enabled on systems like the 8xx or
827 8260 (where accesses to the IMMR region must be
828 uncached), and it cannot be disabled on all other
829 systems where we (mis-) use the data cache to hold an
830 initial stack and some data.
833 XXX - this list needs to get updated!
835 - Device tree:
836 CONFIG_OF_CONTROL
837 If this variable is defined, U-Boot will use a device tree
838 to configure its devices, instead of relying on statically
839 compiled #defines in the board file. This option is
840 experimental and only available on a few boards. The device
841 tree is available in the global data as gd->fdt_blob.
843 U-Boot needs to get its device tree from somewhere. This can
844 be done using one of the two options below:
846 CONFIG_OF_EMBED
847 If this variable is defined, U-Boot will embed a device tree
848 binary in its image. This device tree file should be in the
849 board directory and called <soc>-<board>.dts. The binary file
850 is then picked up in board_init_f() and made available through
851 the global data structure as gd->blob.
853 CONFIG_OF_SEPARATE
854 If this variable is defined, U-Boot will build a device tree
855 binary. It will be called u-boot.dtb. Architecture-specific
856 code will locate it at run-time. Generally this works by:
858 cat u-boot.bin u-boot.dtb >image.bin
860 and in fact, U-Boot does this for you, creating a file called
861 u-boot-dtb.bin which is useful in the common case. You can
862 still use the individual files if you need something more
863 exotic.
865 - Watchdog:
866 CONFIG_WATCHDOG
867 If this variable is defined, it enables watchdog
868 support for the SoC. There must be support in the SoC
869 specific code for a watchdog. For the 8xx and 8260
870 CPUs, the SIU Watchdog feature is enabled in the SYPCR
871 register. When supported for a specific SoC is
872 available, then no further board specific code should
873 be needed to use it.
875 CONFIG_HW_WATCHDOG
876 When using a watchdog circuitry external to the used
877 SoC, then define this variable and provide board
878 specific code for the "hw_watchdog_reset" function.
880 - U-Boot Version:
881 CONFIG_VERSION_VARIABLE
882 If this variable is defined, an environment variable
883 named "ver" is created by U-Boot showing the U-Boot
884 version as printed by the "version" command.
885 This variable is readonly.
887 - Real-Time Clock:
889 When CONFIG_CMD_DATE is selected, the type of the RTC
890 has to be selected, too. Define exactly one of the
891 following options:
893 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx
894 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
895 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC
896 CONFIG_RTC_MC146818 - use MC146818 RTC
897 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
898 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
899 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
900 CONFIG_RTC_DS164x - use Dallas DS164x RTC
901 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC
902 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
903 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337
904 CONFIG_SYS_RV3029_TCR - enable trickle charger on
905 RV3029 RTC.
907 Note that if the RTC uses I2C, then the I2C interface
908 must also be configured. See I2C Support, below.
910 - GPIO Support:
911 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO
912 CONFIG_PCA953X_INFO - enable pca953x info command
914 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of
915 chip-ngpio pairs that tell the PCA953X driver the number of
916 pins supported by a particular chip.
918 Note that if the GPIO device uses I2C, then the I2C interface
919 must also be configured. See I2C Support, below.
921 - Timestamp Support:
923 When CONFIG_TIMESTAMP is selected, the timestamp
924 (date and time) of an image is printed by image
925 commands like bootm or iminfo. This option is
926 automatically enabled when you select CONFIG_CMD_DATE .
928 - Partition Support:
929 CONFIG_MAC_PARTITION and/or CONFIG_DOS_PARTITION
930 and/or CONFIG_ISO_PARTITION and/or CONFIG_EFI_PARTITION
932 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or
933 CONFIG_CMD_SCSI) you must configure support for at
934 least one partition type as well.
936 - IDE Reset method:
937 CONFIG_IDE_RESET_ROUTINE - this is defined in several
938 board configurations files but used nowhere!
940 CONFIG_IDE_RESET - is this is defined, IDE Reset will
941 be performed by calling the function
942 ide_set_reset(int reset)
943 which has to be defined in a board specific file
945 - ATAPI Support:
946 CONFIG_ATAPI
948 Set this to enable ATAPI support.
950 - LBA48 Support
951 CONFIG_LBA48
953 Set this to enable support for disks larger than 137GB
954 Also look at CONFIG_SYS_64BIT_LBA.
955 Whithout these , LBA48 support uses 32bit variables and will 'only'
956 support disks up to 2.1TB.
958 CONFIG_SYS_64BIT_LBA:
959 When enabled, makes the IDE subsystem use 64bit sector addresses.
960 Default is 32bit.
962 - SCSI Support:
963 At the moment only there is only support for the
964 SYM53C8XX SCSI controller; define
965 CONFIG_SCSI_SYM53C8XX to enable it.
967 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and
968 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID *
969 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the
970 maximum numbers of LUNs, SCSI ID's and target
971 devices.
972 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
974 - NETWORK Support (PCI):
975 CONFIG_E1000
976 Support for Intel 8254x/8257x gigabit chips.
978 CONFIG_E1000_SPI
979 Utility code for direct access to the SPI bus on Intel 8257x.
980 This does not do anything useful unless you set at least one
981 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC.
983 CONFIG_E1000_SPI_GENERIC
984 Allow generic access to the SPI bus on the Intel 8257x, for
985 example with the "sspi" command.
987 CONFIG_CMD_E1000
988 Management command for E1000 devices. When used on devices
989 with SPI support you can reprogram the EEPROM from U-Boot.
991 CONFIG_E1000_FALLBACK_MAC
992 default MAC for empty EEPROM after production.
994 CONFIG_EEPRO100
995 Support for Intel 82557/82559/82559ER chips.
996 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM
997 write routine for first time initialisation.
999 CONFIG_TULIP
1000 Support for Digital 2114x chips.
1001 Optional CONFIG_TULIP_SELECT_MEDIA for board specific
1002 modem chip initialisation (KS8761/QS6611).
1004 CONFIG_NATSEMI
1005 Support for National dp83815 chips.
1007 CONFIG_NS8382X
1008 Support for National dp8382[01] gigabit chips.
1010 - NETWORK Support (other):
1012 CONFIG_DRIVER_AT91EMAC
1013 Support for AT91RM9200 EMAC.
1015 CONFIG_RMII
1016 Define this to use reduced MII inteface
1018 CONFIG_DRIVER_AT91EMAC_QUIET
1019 If this defined, the driver is quiet.
1020 The driver doen't show link status messages.
1022 CONFIG_CALXEDA_XGMAC
1023 Support for the Calxeda XGMAC device
1025 CONFIG_DRIVER_LAN91C96
1026 Support for SMSC's LAN91C96 chips.
1028 CONFIG_LAN91C96_BASE
1029 Define this to hold the physical address
1030 of the LAN91C96's I/O space
1032 CONFIG_LAN91C96_USE_32_BIT
1033 Define this to enable 32 bit addressing
1035 CONFIG_DRIVER_SMC91111
1036 Support for SMSC's LAN91C111 chip
1038 CONFIG_SMC91111_BASE
1039 Define this to hold the physical address
1040 of the device (I/O space)
1042 CONFIG_SMC_USE_32_BIT
1043 Define this if data bus is 32 bits
1045 CONFIG_SMC_USE_IOFUNCS
1046 Define this to use i/o functions instead of macros
1047 (some hardware wont work with macros)
1049 CONFIG_DRIVER_TI_EMAC
1050 Support for davinci emac
1052 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT
1053 Define this if you have more then 3 PHYs.
1055 CONFIG_FTGMAC100
1056 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet
1058 CONFIG_FTGMAC100_EGIGA
1059 Define this to use GE link update with gigabit PHY.
1060 Define this if FTGMAC100 is connected to gigabit PHY.
1061 If your system has 10/100 PHY only, it might not occur
1062 wrong behavior. Because PHY usually return timeout or
1063 useless data when polling gigabit status and gigabit
1064 control registers. This behavior won't affect the
1065 correctnessof 10/100 link speed update.
1067 CONFIG_SMC911X
1068 Support for SMSC's LAN911x and LAN921x chips
1070 CONFIG_SMC911X_BASE
1071 Define this to hold the physical address
1072 of the device (I/O space)
1074 CONFIG_SMC911X_32_BIT
1075 Define this if data bus is 32 bits
1077 CONFIG_SMC911X_16_BIT
1078 Define this if data bus is 16 bits. If your processor
1079 automatically converts one 32 bit word to two 16 bit
1080 words you may also try CONFIG_SMC911X_32_BIT.
1082 CONFIG_SH_ETHER
1083 Support for Renesas on-chip Ethernet controller
1085 CONFIG_SH_ETHER_USE_PORT
1086 Define the number of ports to be used
1088 CONFIG_SH_ETHER_PHY_ADDR
1089 Define the ETH PHY's address
1091 CONFIG_SH_ETHER_CACHE_WRITEBACK
1092 If this option is set, the driver enables cache flush.
1094 - TPM Support:
1095 CONFIG_GENERIC_LPC_TPM
1096 Support for generic parallel port TPM devices. Only one device
1097 per system is supported at this time.
1099 CONFIG_TPM_TIS_BASE_ADDRESS
1100 Base address where the generic TPM device is mapped
1101 to. Contemporary x86 systems usually map it at
1102 0xfed40000.
1104 - USB Support:
1105 At the moment only the UHCI host controller is
1106 supported (PIP405, MIP405, MPC5200); define
1107 CONFIG_USB_UHCI to enable it.
1108 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
1109 and define CONFIG_USB_STORAGE to enable the USB
1110 storage devices.
1111 Note:
1112 Supported are USB Keyboards and USB Floppy drives
1113 (TEAC FD-05PUB).
1114 MPC5200 USB requires additional defines:
1115 CONFIG_USB_CLOCK
1116 for 528 MHz Clock: 0x0001bbbb
1117 CONFIG_PSC3_USB
1118 for USB on PSC3
1119 CONFIG_USB_CONFIG
1120 for differential drivers: 0x00001000
1121 for single ended drivers: 0x00005000
1122 for differential drivers on PSC3: 0x00000100
1123 for single ended drivers on PSC3: 0x00004100
1124 CONFIG_SYS_USB_EVENT_POLL
1125 May be defined to allow interrupt polling
1126 instead of using asynchronous interrupts
1128 - USB Device:
1129 Define the below if you wish to use the USB console.
1130 Once firmware is rebuilt from a serial console issue the
1131 command "setenv stdin usbtty; setenv stdout usbtty" and
1132 attach your USB cable. The Unix command "dmesg" should print
1133 it has found a new device. The environment variable usbtty
1134 can be set to gserial or cdc_acm to enable your device to
1135 appear to a USB host as a Linux gserial device or a
1136 Common Device Class Abstract Control Model serial device.
1137 If you select usbtty = gserial you should be able to enumerate
1138 a Linux host by
1139 # modprobe usbserial vendor=0xVendorID product=0xProductID
1140 else if using cdc_acm, simply setting the environment
1141 variable usbtty to be cdc_acm should suffice. The following
1142 might be defined in YourBoardName.h
1144 CONFIG_USB_DEVICE
1145 Define this to build a UDC device
1147 CONFIG_USB_TTY
1148 Define this to have a tty type of device available to
1149 talk to the UDC device
1151 CONFIG_SYS_CONSOLE_IS_IN_ENV
1152 Define this if you want stdin, stdout &/or stderr to
1153 be set to usbtty.
1155 mpc8xx:
1156 CONFIG_SYS_USB_EXTC_CLK 0xBLAH
1157 Derive USB clock from external clock "blah"
1158 - CONFIG_SYS_USB_EXTC_CLK 0x02
1160 CONFIG_SYS_USB_BRG_CLK 0xBLAH
1161 Derive USB clock from brgclk
1162 - CONFIG_SYS_USB_BRG_CLK 0x04
1164 If you have a USB-IF assigned VendorID then you may wish to
1165 define your own vendor specific values either in BoardName.h
1166 or directly in usbd_vendor_info.h. If you don't define
1167 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME,
1168 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot
1169 should pretend to be a Linux device to it's target host.
1171 CONFIG_USBD_MANUFACTURER
1172 Define this string as the name of your company for
1173 - CONFIG_USBD_MANUFACTURER "my company"
1175 CONFIG_USBD_PRODUCT_NAME
1176 Define this string as the name of your product
1177 - CONFIG_USBD_PRODUCT_NAME "acme usb device"
1179 CONFIG_USBD_VENDORID
1180 Define this as your assigned Vendor ID from the USB
1181 Implementors Forum. This *must* be a genuine Vendor ID
1182 to avoid polluting the USB namespace.
1183 - CONFIG_USBD_VENDORID 0xFFFF
1185 CONFIG_USBD_PRODUCTID
1186 Define this as the unique Product ID
1187 for your device
1188 - CONFIG_USBD_PRODUCTID 0xFFFF
1190 - ULPI Layer Support:
1191 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via
1192 the generic ULPI layer. The generic layer accesses the ULPI PHY
1193 via the platform viewport, so you need both the genric layer and
1194 the viewport enabled. Currently only Chipidea/ARC based
1195 viewport is supported.
1196 To enable the ULPI layer support, define CONFIG_USB_ULPI and
1197 CONFIG_USB_ULPI_VIEWPORT in your board configuration file.
1199 - MMC Support:
1200 The MMC controller on the Intel PXA is supported. To
1201 enable this define CONFIG_MMC. The MMC can be
1202 accessed from the boot prompt by mapping the device
1203 to physical memory similar to flash. Command line is
1204 enabled with CONFIG_CMD_MMC. The MMC driver also works with
1205 the FAT fs. This is enabled with CONFIG_CMD_FAT.
1207 CONFIG_SH_MMCIF
1208 Support for Renesas on-chip MMCIF controller
1210 CONFIG_SH_MMCIF_ADDR
1211 Define the base address of MMCIF registers
1213 CONFIG_SH_MMCIF_CLK
1214 Define the clock frequency for MMCIF
1216 - Journaling Flash filesystem support:
1217 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE,
1218 CONFIG_JFFS2_NAND_DEV
1219 Define these for a default partition on a NAND device
1221 CONFIG_SYS_JFFS2_FIRST_SECTOR,
1222 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS
1223 Define these for a default partition on a NOR device
1225 CONFIG_SYS_JFFS_CUSTOM_PART
1226 Define this to create an own partition. You have to provide a
1227 function struct part_info* jffs2_part_info(int part_num)
1229 If you define only one JFFS2 partition you may also want to
1230 #define CONFIG_SYS_JFFS_SINGLE_PART 1
1231 to disable the command chpart. This is the default when you
1232 have not defined a custom partition
1234 - FAT(File Allocation Table) filesystem write function support:
1235 CONFIG_FAT_WRITE
1236 Support for saving memory data as a file
1237 in FAT formatted partition
1239 - Keyboard Support:
1240 CONFIG_ISA_KEYBOARD
1242 Define this to enable standard (PC-Style) keyboard
1243 support
1245 CONFIG_I8042_KBD
1246 Standard PC keyboard driver with US (is default) and
1247 GERMAN key layout (switch via environment 'keymap=de') support.
1248 Export function i8042_kbd_init, i8042_tstc and i8042_getc
1249 for cfb_console. Supports cursor blinking.
1251 - Video support:
1252 CONFIG_VIDEO
1254 Define this to enable video support (for output to
1255 video).
1257 CONFIG_VIDEO_CT69000
1259 Enable Chips & Technologies 69000 Video chip
1261 CONFIG_VIDEO_SMI_LYNXEM
1262 Enable Silicon Motion SMI 712/710/810 Video chip. The
1263 video output is selected via environment 'videoout'
1264 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is
1265 assumed.
1267 For the CT69000 and SMI_LYNXEM drivers, videomode is
1268 selected via environment 'videomode'. Two different ways
1269 are possible:
1270 - "videomode=num" 'num' is a standard LiLo mode numbers.
1271 Following standard modes are supported (* is default):
1273 Colors 640x480 800x600 1024x768 1152x864 1280x1024
1274 -------------+---------------------------------------------
1275 8 bits | 0x301* 0x303 0x305 0x161 0x307
1276 15 bits | 0x310 0x313 0x316 0x162 0x319
1277 16 bits | 0x311 0x314 0x317 0x163 0x31A
1278 24 bits | 0x312 0x315 0x318 ? 0x31B
1279 -------------+---------------------------------------------
1280 (i.e. setenv videomode 317; saveenv; reset;)
1282 - "videomode=bootargs" all the video parameters are parsed
1283 from the bootargs. (See drivers/video/videomodes.c)
1286 CONFIG_VIDEO_SED13806
1287 Enable Epson SED13806 driver. This driver supports 8bpp
1288 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
1289 or CONFIG_VIDEO_SED13806_16BPP
1291 CONFIG_FSL_DIU_FB
1292 Enable the Freescale DIU video driver. Reference boards for
1293 SOCs that have a DIU should define this macro to enable DIU
1294 support, and should also define these other macros:
1296 CONFIG_SYS_DIU_ADDR
1297 CONFIG_VIDEO
1298 CONFIG_CMD_BMP
1299 CONFIG_CFB_CONSOLE
1300 CONFIG_VIDEO_SW_CURSOR
1301 CONFIG_VGA_AS_SINGLE_DEVICE
1302 CONFIG_VIDEO_LOGO
1303 CONFIG_VIDEO_BMP_LOGO
1305 The DIU driver will look for the 'video-mode' environment
1306 variable, and if defined, enable the DIU as a console during
1307 boot. See the documentation file README.video for a
1308 description of this variable.
1310 - Keyboard Support:
1311 CONFIG_KEYBOARD
1313 Define this to enable a custom keyboard support.
1314 This simply calls drv_keyboard_init() which must be
1315 defined in your board-specific files.
1316 The only board using this so far is RBC823.
1318 - LCD Support: CONFIG_LCD
1320 Define this to enable LCD support (for output to LCD
1321 display); also select one of the supported displays
1322 by defining one of these:
1324 CONFIG_ATMEL_LCD:
1326 HITACHI TX09D70VM1CCA, 3.5", 240x320.
1328 CONFIG_NEC_NL6448AC33:
1330 NEC NL6448AC33-18. Active, color, single scan.
1332 CONFIG_NEC_NL6448BC20
1334 NEC NL6448BC20-08. 6.5", 640x480.
1335 Active, color, single scan.
1337 CONFIG_NEC_NL6448BC33_54
1339 NEC NL6448BC33-54. 10.4", 640x480.
1340 Active, color, single scan.
1342 CONFIG_SHARP_16x9
1344 Sharp 320x240. Active, color, single scan.
1345 It isn't 16x9, and I am not sure what it is.
1347 CONFIG_SHARP_LQ64D341
1349 Sharp LQ64D341 display, 640x480.
1350 Active, color, single scan.
1352 CONFIG_HLD1045
1354 HLD1045 display, 640x480.
1355 Active, color, single scan.
1357 CONFIG_OPTREX_BW
1359 Optrex CBL50840-2 NF-FW 99 22 M5
1360 or
1361 Hitachi LMG6912RPFC-00T
1362 or
1363 Hitachi SP14Q002
1365 320x240. Black & white.
1367 Normally display is black on white background; define
1368 CONFIG_SYS_WHITE_ON_BLACK to get it inverted.
1370 - Splash Screen Support: CONFIG_SPLASH_SCREEN
1372 If this option is set, the environment is checked for
1373 a variable "splashimage". If found, the usual display
1374 of logo, copyright and system information on the LCD
1375 is suppressed and the BMP image at the address
1376 specified in "splashimage" is loaded instead. The
1377 console is redirected to the "nulldev", too. This
1378 allows for a "silent" boot where a splash screen is
1379 loaded very quickly after power-on.
1381 CONFIG_SPLASH_SCREEN_ALIGN
1383 If this option is set the splash image can be freely positioned
1384 on the screen. Environment variable "splashpos" specifies the
1385 position as "x,y". If a positive number is given it is used as
1386 number of pixel from left/top. If a negative number is given it
1387 is used as number of pixel from right/bottom. You can also
1388 specify 'm' for centering the image.
1390 Example:
1391 setenv splashpos m,m
1392 => image at center of screen
1394 setenv splashpos 30,20
1395 => image at x = 30 and y = 20
1397 setenv splashpos -10,m
1398 => vertically centered image
1399 at x = dspWidth - bmpWidth - 9
1401 - Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
1403 If this option is set, additionally to standard BMP
1404 images, gzipped BMP images can be displayed via the
1405 splashscreen support or the bmp command.
1407 - Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8
1409 If this option is set, 8-bit RLE compressed BMP images
1410 can be displayed via the splashscreen support or the
1411 bmp command.
1413 - Compression support:
1414 CONFIG_BZIP2
1416 If this option is set, support for bzip2 compressed
1417 images is included. If not, only uncompressed and gzip
1418 compressed images are supported.
1420 NOTE: the bzip2 algorithm requires a lot of RAM, so
1421 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should
1422 be at least 4MB.
1424 CONFIG_LZMA
1426 If this option is set, support for lzma compressed
1427 images is included.
1429 Note: The LZMA algorithm adds between 2 and 4KB of code and it
1430 requires an amount of dynamic memory that is given by the
1431 formula:
1433 (1846 + 768 << (lc + lp)) * sizeof(uint16)
1435 Where lc and lp stand for, respectively, Literal context bits
1436 and Literal pos bits.
1438 This value is upper-bounded by 14MB in the worst case. Anyway,
1439 for a ~4MB large kernel image, we have lc=3 and lp=0 for a
1440 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is
1441 a very small buffer.
1443 Use the lzmainfo tool to determinate the lc and lp values and
1444 then calculate the amount of needed dynamic memory (ensuring
1445 the appropriate CONFIG_SYS_MALLOC_LEN value).
1447 - MII/PHY support:
1448 CONFIG_PHY_ADDR
1450 The address of PHY on MII bus.
1452 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
1454 The clock frequency of the MII bus
1456 CONFIG_PHY_GIGE
1458 If this option is set, support for speed/duplex
1459 detection of gigabit PHY is included.
1461 CONFIG_PHY_RESET_DELAY
1463 Some PHY like Intel LXT971A need extra delay after
1464 reset before any MII register access is possible.
1465 For such PHY, set this option to the usec delay
1466 required. (minimum 300usec for LXT971A)
1468 CONFIG_PHY_CMD_DELAY (ppc4xx)
1470 Some PHY like Intel LXT971A need extra delay after
1471 command issued before MII status register can be read
1473 - Ethernet address:
1474 CONFIG_ETHADDR
1475 CONFIG_ETH1ADDR
1476 CONFIG_ETH2ADDR
1477 CONFIG_ETH3ADDR
1478 CONFIG_ETH4ADDR
1479 CONFIG_ETH5ADDR
1481 Define a default value for Ethernet address to use
1482 for the respective Ethernet interface, in case this
1483 is not determined automatically.
1485 - IP address:
1486 CONFIG_IPADDR
1488 Define a default value for the IP address to use for
1489 the default Ethernet interface, in case this is not
1490 determined through e.g. bootp.
1491 (Environment variable "ipaddr")
1493 - Server IP address:
1494 CONFIG_SERVERIP
1496 Defines a default value for the IP address of a TFTP
1497 server to contact when using the "tftboot" command.
1498 (Environment variable "serverip")
1500 CONFIG_KEEP_SERVERADDR
1502 Keeps the server's MAC address, in the env 'serveraddr'
1503 for passing to bootargs (like Linux's netconsole option)
1505 - Gateway IP address:
1506 CONFIG_GATEWAYIP
1508 Defines a default value for the IP address of the
1509 default router where packets to other networks are
1510 sent to.
1511 (Environment variable "gatewayip")
1513 - Subnet mask:
1514 CONFIG_NETMASK
1516 Defines a default value for the subnet mask (or
1517 routing prefix) which is used to determine if an IP
1518 address belongs to the local subnet or needs to be
1519 forwarded through a router.
1520 (Environment variable "netmask")
1522 - Multicast TFTP Mode:
1523 CONFIG_MCAST_TFTP
1525 Defines whether you want to support multicast TFTP as per
1526 rfc-2090; for example to work with atftp. Lets lots of targets
1527 tftp down the same boot image concurrently. Note: the Ethernet
1528 driver in use must provide a function: mcast() to join/leave a
1529 multicast group.
1531 - BOOTP Recovery Mode:
1532 CONFIG_BOOTP_RANDOM_DELAY
1534 If you have many targets in a network that try to
1535 boot using BOOTP, you may want to avoid that all
1536 systems send out BOOTP requests at precisely the same
1537 moment (which would happen for instance at recovery
1538 from a power failure, when all systems will try to
1539 boot, thus flooding the BOOTP server. Defining
1540 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
1541 inserted before sending out BOOTP requests. The
1542 following delays are inserted then:
1544 1st BOOTP request: delay 0 ... 1 sec
1545 2nd BOOTP request: delay 0 ... 2 sec
1546 3rd BOOTP request: delay 0 ... 4 sec
1547 4th and following
1548 BOOTP requests: delay 0 ... 8 sec
1550 - DHCP Advanced Options:
1551 You can fine tune the DHCP functionality by defining
1552 CONFIG_BOOTP_* symbols:
1554 CONFIG_BOOTP_SUBNETMASK
1555 CONFIG_BOOTP_GATEWAY
1556 CONFIG_BOOTP_HOSTNAME
1557 CONFIG_BOOTP_NISDOMAIN
1558 CONFIG_BOOTP_BOOTPATH
1559 CONFIG_BOOTP_BOOTFILESIZE
1560 CONFIG_BOOTP_DNS
1561 CONFIG_BOOTP_DNS2
1562 CONFIG_BOOTP_SEND_HOSTNAME
1563 CONFIG_BOOTP_NTPSERVER
1564 CONFIG_BOOTP_TIMEOFFSET
1565 CONFIG_BOOTP_VENDOREX
1567 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip
1568 environment variable, not the BOOTP server.
1570 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
1571 serverip from a DHCP server, it is possible that more
1572 than one DNS serverip is offered to the client.
1573 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
1574 serverip will be stored in the additional environment
1575 variable "dnsip2". The first DNS serverip is always
1576 stored in the variable "dnsip", when CONFIG_BOOTP_DNS
1577 is defined.
1579 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
1580 to do a dynamic update of a DNS server. To do this, they
1581 need the hostname of the DHCP requester.
1582 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content
1583 of the "hostname" environment variable is passed as
1584 option 12 to the DHCP server.
1586 CONFIG_BOOTP_DHCP_REQUEST_DELAY
1588 A 32bit value in microseconds for a delay between
1589 receiving a "DHCP Offer" and sending the "DHCP Request".
1590 This fixes a problem with certain DHCP servers that don't
1591 respond 100% of the time to a "DHCP request". E.g. On an
1592 AT91RM9200 processor running at 180MHz, this delay needed
1593 to be *at least* 15,000 usec before a Windows Server 2003
1594 DHCP server would reply 100% of the time. I recommend at
1595 least 50,000 usec to be safe. The alternative is to hope
1596 that one of the retries will be successful but note that
1597 the DHCP timeout and retry process takes a longer than
1598 this delay.
1600 - CDP Options:
1601 CONFIG_CDP_DEVICE_ID
1603 The device id used in CDP trigger frames.
1605 CONFIG_CDP_DEVICE_ID_PREFIX
1607 A two character string which is prefixed to the MAC address
1608 of the device.
1610 CONFIG_CDP_PORT_ID
1612 A printf format string which contains the ascii name of
1613 the port. Normally is set to "eth%d" which sets
1614 eth0 for the first Ethernet, eth1 for the second etc.
1616 CONFIG_CDP_CAPABILITIES
1618 A 32bit integer which indicates the device capabilities;
1619 0x00000010 for a normal host which does not forwards.
1621 CONFIG_CDP_VERSION
1623 An ascii string containing the version of the software.
1625 CONFIG_CDP_PLATFORM
1627 An ascii string containing the name of the platform.
1629 CONFIG_CDP_TRIGGER
1631 A 32bit integer sent on the trigger.
1633 CONFIG_CDP_POWER_CONSUMPTION
1635 A 16bit integer containing the power consumption of the
1636 device in .1 of milliwatts.
1638 CONFIG_CDP_APPLIANCE_VLAN_TYPE
1640 A byte containing the id of the VLAN.
1642 - Status LED: CONFIG_STATUS_LED
1644 Several configurations allow to display the current
1645 status using a LED. For instance, the LED will blink
1646 fast while running U-Boot code, stop blinking as
1647 soon as a reply to a BOOTP request was received, and
1648 start blinking slow once the Linux kernel is running
1649 (supported by a status LED driver in the Linux
1650 kernel). Defining CONFIG_STATUS_LED enables this
1651 feature in U-Boot.
1653 - CAN Support: CONFIG_CAN_DRIVER
1655 Defining CONFIG_CAN_DRIVER enables CAN driver support
1656 on those systems that support this (optional)
1657 feature, like the TQM8xxL modules.
1659 - I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C
1661 These enable I2C serial bus commands. Defining either of
1662 (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will
1663 include the appropriate I2C driver for the selected CPU.
1665 This will allow you to use i2c commands at the u-boot
1666 command line (as long as you set CONFIG_CMD_I2C in
1667 CONFIG_COMMANDS) and communicate with i2c based realtime
1668 clock chips. See common/cmd_i2c.c for a description of the
1669 command line interface.
1671 CONFIG_HARD_I2C selects a hardware I2C controller.
1673 CONFIG_SOFT_I2C configures u-boot to use a software (aka
1674 bit-banging) driver instead of CPM or similar hardware
1675 support for I2C.
1677 There are several other quantities that must also be
1678 defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C.
1680 In both cases you will need to define CONFIG_SYS_I2C_SPEED
1681 to be the frequency (in Hz) at which you wish your i2c bus
1682 to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie
1683 the CPU's i2c node address).
1685 Now, the u-boot i2c code for the mpc8xx
1686 (arch/powerpc/cpu/mpc8xx/i2c.c) sets the CPU up as a master node
1687 and so its address should therefore be cleared to 0 (See,
1688 eg, MPC823e User's Manual p.16-473). So, set
1689 CONFIG_SYS_I2C_SLAVE to 0.
1691 CONFIG_SYS_I2C_INIT_MPC5XXX
1693 When a board is reset during an i2c bus transfer
1694 chips might think that the current transfer is still
1695 in progress. Reset the slave devices by sending start
1696 commands until the slave device responds.
1698 That's all that's required for CONFIG_HARD_I2C.
1700 If you use the software i2c interface (CONFIG_SOFT_I2C)
1701 then the following macros need to be defined (examples are
1702 from include/configs/lwmon.h):
1704 I2C_INIT
1706 (Optional). Any commands necessary to enable the I2C
1707 controller or configure ports.
1709 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
1711 I2C_PORT
1713 (Only for MPC8260 CPU). The I/O port to use (the code
1714 assumes both bits are on the same port). Valid values
1715 are 0..3 for ports A..D.
1717 I2C_ACTIVE
1719 The code necessary to make the I2C data line active
1720 (driven). If the data line is open collector, this
1721 define can be null.
1723 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
1725 I2C_TRISTATE
1727 The code necessary to make the I2C data line tri-stated
1728 (inactive). If the data line is open collector, this
1729 define can be null.
1731 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
1733 I2C_READ
1735 Code that returns TRUE if the I2C data line is high,
1736 FALSE if it is low.
1738 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
1740 I2C_SDA(bit)
1742 If <bit> is TRUE, sets the I2C data line high. If it
1743 is FALSE, it clears it (low).
1745 eg: #define I2C_SDA(bit) \
1746 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
1747 else immr->im_cpm.cp_pbdat &= ~PB_SDA
1749 I2C_SCL(bit)
1751 If <bit> is TRUE, sets the I2C clock line high. If it
1752 is FALSE, it clears it (low).
1754 eg: #define I2C_SCL(bit) \
1755 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
1756 else immr->im_cpm.cp_pbdat &= ~PB_SCL
1758 I2C_DELAY
1760 This delay is invoked four times per clock cycle so this
1761 controls the rate of data transfer. The data rate thus
1762 is 1 / (I2C_DELAY * 4). Often defined to be something
1763 like:
1765 #define I2C_DELAY udelay(2)
1767 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA
1769 If your arch supports the generic GPIO framework (asm/gpio.h),
1770 then you may alternatively define the two GPIOs that are to be
1771 used as SCL / SDA. Any of the previous I2C_xxx macros will
1772 have GPIO-based defaults assigned to them as appropriate.
1774 You should define these to the GPIO value as given directly to
1775 the generic GPIO functions.
1777 CONFIG_SYS_I2C_INIT_BOARD
1779 When a board is reset during an i2c bus transfer
1780 chips might think that the current transfer is still
1781 in progress. On some boards it is possible to access
1782 the i2c SCLK line directly, either by using the
1783 processor pin as a GPIO or by having a second pin
1784 connected to the bus. If this option is defined a
1785 custom i2c_init_board() routine in boards/xxx/board.c
1786 is run early in the boot sequence.
1788 CONFIG_SYS_I2C_BOARD_LATE_INIT
1790 An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is
1791 defined a custom i2c_board_late_init() routine in
1792 boards/xxx/board.c is run AFTER the operations in i2c_init()
1793 is completed. This callpoint can be used to unreset i2c bus
1794 using CPU i2c controller register accesses for CPUs whose i2c
1795 controller provide such a method. It is called at the end of
1796 i2c_init() to allow i2c_init operations to setup the i2c bus
1797 controller on the CPU (e.g. setting bus speed & slave address).
1799 CONFIG_I2CFAST (PPC405GP|PPC405EP only)
1801 This option enables configuration of bi_iic_fast[] flags
1802 in u-boot bd_info structure based on u-boot environment
1803 variable "i2cfast". (see also i2cfast)
1805 CONFIG_I2C_MULTI_BUS
1807 This option allows the use of multiple I2C buses, each of which
1808 must have a controller. At any point in time, only one bus is
1809 active. To switch to a different bus, use the 'i2c dev' command.
1810 Note that bus numbering is zero-based.
1812 CONFIG_SYS_I2C_NOPROBES
1814 This option specifies a list of I2C devices that will be skipped
1815 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS
1816 is set, specify a list of bus-device pairs. Otherwise, specify
1817 a 1D array of device addresses
1819 e.g.
1820 #undef CONFIG_I2C_MULTI_BUS
1821 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68}
1823 will skip addresses 0x50 and 0x68 on a board with one I2C bus
1825 #define CONFIG_I2C_MULTI_BUS
1826 #define CONFIG_SYS_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}}
1828 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1
1830 CONFIG_SYS_SPD_BUS_NUM
1832 If defined, then this indicates the I2C bus number for DDR SPD.
1833 If not defined, then U-Boot assumes that SPD is on I2C bus 0.
1835 CONFIG_SYS_RTC_BUS_NUM
1837 If defined, then this indicates the I2C bus number for the RTC.
1838 If not defined, then U-Boot assumes that RTC is on I2C bus 0.
1840 CONFIG_SYS_DTT_BUS_NUM
1842 If defined, then this indicates the I2C bus number for the DTT.
1843 If not defined, then U-Boot assumes that DTT is on I2C bus 0.
1845 CONFIG_SYS_I2C_DTT_ADDR:
1847 If defined, specifies the I2C address of the DTT device.
1848 If not defined, then U-Boot uses predefined value for
1849 specified DTT device.
1851 CONFIG_FSL_I2C
1853 Define this option if you want to use Freescale's I2C driver in
1854 drivers/i2c/fsl_i2c.c.
1856 CONFIG_I2C_MUX
1858 Define this option if you have I2C devices reached over 1 .. n
1859 I2C Muxes like the pca9544a. This option addes a new I2C
1860 Command "i2c bus [muxtype:muxaddr:muxchannel]" which adds a
1861 new I2C Bus to the existing I2C Busses. If you select the
1862 new Bus with "i2c dev", u-bbot sends first the commandos for
1863 the muxes to activate this new "bus".
1865 CONFIG_I2C_MULTI_BUS must be also defined, to use this
1866 feature!
1868 Example:
1869 Adding a new I2C Bus reached over 2 pca9544a muxes
1870 The First mux with address 70 and channel 6
1871 The Second mux with address 71 and channel 4
1873 => i2c bus pca9544a:70:6:pca9544a:71:4
1875 Use the "i2c bus" command without parameter, to get a list
1876 of I2C Busses with muxes:
1878 => i2c bus
1879 Busses reached over muxes:
1880 Bus ID: 2
1881 reached over Mux(es):
1882 pca9544a@70 ch: 4
1883 Bus ID: 3
1884 reached over Mux(es):
1885 pca9544a@70 ch: 6
1886 pca9544a@71 ch: 4
1887 =>
1889 If you now switch to the new I2C Bus 3 with "i2c dev 3"
1890 u-boot first sends the command to the mux@70 to enable
1891 channel 6, and then the command to the mux@71 to enable
1892 the channel 4.
1894 After that, you can use the "normal" i2c commands as
1895 usual to communicate with your I2C devices behind
1896 the 2 muxes.
1898 This option is actually implemented for the bitbanging
1899 algorithm in common/soft_i2c.c and for the Hardware I2C
1900 Bus on the MPC8260. But it should be not so difficult
1901 to add this option to other architectures.
1903 CONFIG_SOFT_I2C_READ_REPEATED_START
1905 defining this will force the i2c_read() function in
1906 the soft_i2c driver to perform an I2C repeated start
1907 between writing the address pointer and reading the
1908 data. If this define is omitted the default behaviour
1909 of doing a stop-start sequence will be used. Most I2C
1910 devices can use either method, but some require one or
1911 the other.
1913 - SPI Support: CONFIG_SPI
1915 Enables SPI driver (so far only tested with
1916 SPI EEPROM, also an instance works with Crystal A/D and
1917 D/As on the SACSng board)
1919 CONFIG_SH_SPI
1921 Enables the driver for SPI controller on SuperH. Currently
1922 only SH7757 is supported.
1924 CONFIG_SPI_X
1926 Enables extended (16-bit) SPI EEPROM addressing.
1927 (symmetrical to CONFIG_I2C_X)
1929 CONFIG_SOFT_SPI
1931 Enables a software (bit-bang) SPI driver rather than
1932 using hardware support. This is a general purpose
1933 driver that only requires three general I/O port pins
1934 (two outputs, one input) to function. If this is
1935 defined, the board configuration must define several
1936 SPI configuration items (port pins to use, etc). For
1937 an example, see include/configs/sacsng.h.
1939 CONFIG_HARD_SPI
1941 Enables a hardware SPI driver for general-purpose reads
1942 and writes. As with CONFIG_SOFT_SPI, the board configuration
1943 must define a list of chip-select function pointers.
1944 Currently supported on some MPC8xxx processors. For an
1945 example, see include/configs/mpc8349emds.h.
1947 CONFIG_MXC_SPI
1949 Enables the driver for the SPI controllers on i.MX and MXC
1950 SoCs. Currently i.MX31/35/51 are supported.
1952 - FPGA Support: CONFIG_FPGA
1954 Enables FPGA subsystem.
1956 CONFIG_FPGA_<vendor>
1958 Enables support for specific chip vendors.
1959 (ALTERA, XILINX)
1961 CONFIG_FPGA_<family>
1963 Enables support for FPGA family.
1964 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
1966 CONFIG_FPGA_COUNT
1968 Specify the number of FPGA devices to support.
1970 CONFIG_SYS_FPGA_PROG_FEEDBACK
1972 Enable printing of hash marks during FPGA configuration.
1974 CONFIG_SYS_FPGA_CHECK_BUSY
1976 Enable checks on FPGA configuration interface busy
1977 status by the configuration function. This option
1978 will require a board or device specific function to
1979 be written.
1981 CONFIG_FPGA_DELAY
1983 If defined, a function that provides delays in the FPGA
1984 configuration driver.
1986 CONFIG_SYS_FPGA_CHECK_CTRLC
1987 Allow Control-C to interrupt FPGA configuration
1989 CONFIG_SYS_FPGA_CHECK_ERROR
1991 Check for configuration errors during FPGA bitfile
1992 loading. For example, abort during Virtex II
1993 configuration if the INIT_B line goes low (which
1994 indicated a CRC error).
1996 CONFIG_SYS_FPGA_WAIT_INIT
1998 Maximum time to wait for the INIT_B line to deassert
1999 after PROB_B has been deasserted during a Virtex II
2000 FPGA configuration sequence. The default time is 500
2001 ms.
2003 CONFIG_SYS_FPGA_WAIT_BUSY
2005 Maximum time to wait for BUSY to deassert during
2006 Virtex II FPGA configuration. The default is 5 ms.
2008 CONFIG_SYS_FPGA_WAIT_CONFIG
2010 Time to wait after FPGA configuration. The default is
2011 200 ms.
2013 - Configuration Management:
2014 CONFIG_IDENT_STRING
2016 If defined, this string will be added to the U-Boot
2017 version information (U_BOOT_VERSION)
2019 - Vendor Parameter Protection:
2021 U-Boot considers the values of the environment
2022 variables "serial#" (Board Serial Number) and
2023 "ethaddr" (Ethernet Address) to be parameters that
2024 are set once by the board vendor / manufacturer, and
2025 protects these variables from casual modification by
2026 the user. Once set, these variables are read-only,
2027 and write or delete attempts are rejected. You can
2028 change this behaviour:
2030 If CONFIG_ENV_OVERWRITE is #defined in your config
2031 file, the write protection for vendor parameters is
2032 completely disabled. Anybody can change or delete
2033 these parameters.
2035 Alternatively, if you #define _both_ CONFIG_ETHADDR
2036 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
2037 Ethernet address is installed in the environment,
2038 which can be changed exactly ONCE by the user. [The
2039 serial# is unaffected by this, i. e. it remains
2040 read-only.]
2042 - Protected RAM:
2043 CONFIG_PRAM
2045 Define this variable to enable the reservation of
2046 "protected RAM", i. e. RAM which is not overwritten
2047 by U-Boot. Define CONFIG_PRAM to hold the number of
2048 kB you want to reserve for pRAM. You can overwrite
2049 this default value by defining an environment
2050 variable "pram" to the number of kB you want to
2051 reserve. Note that the board info structure will
2052 still show the full amount of RAM. If pRAM is
2053 reserved, a new environment variable "mem" will
2054 automatically be defined to hold the amount of
2055 remaining RAM in a form that can be passed as boot
2056 argument to Linux, for instance like that:
2058 setenv bootargs ... mem=\${mem}
2059 saveenv
2061 This way you can tell Linux not to use this memory,
2062 either, which results in a memory region that will
2063 not be affected by reboots.
2065 *WARNING* If your board configuration uses automatic
2066 detection of the RAM size, you must make sure that
2067 this memory test is non-destructive. So far, the
2068 following board configurations are known to be
2069 "pRAM-clean":
2071 ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL,
2072 HERMES, IP860, RPXlite, LWMON, LANTEC,
2073 FLAGADM, TQM8260
2075 - Error Recovery:
2076 CONFIG_PANIC_HANG
2078 Define this variable to stop the system in case of a
2079 fatal error, so that you have to reset it manually.
2080 This is probably NOT a good idea for an embedded
2081 system where you want the system to reboot
2082 automatically as fast as possible, but it may be
2083 useful during development since you can try to debug
2084 the conditions that lead to the situation.
2086 CONFIG_NET_RETRY_COUNT
2088 This variable defines the number of retries for
2089 network operations like ARP, RARP, TFTP, or BOOTP
2090 before giving up the operation. If not defined, a
2091 default value of 5 is used.
2093 CONFIG_ARP_TIMEOUT
2095 Timeout waiting for an ARP reply in milliseconds.
2097 - Command Interpreter:
2098 CONFIG_AUTO_COMPLETE
2100 Enable auto completion of commands using TAB.
2102 Note that this feature has NOT been implemented yet
2103 for the "hush" shell.
2106 CONFIG_SYS_HUSH_PARSER
2108 Define this variable to enable the "hush" shell (from
2109 Busybox) as command line interpreter, thus enabling
2110 powerful command line syntax like
2111 if...then...else...fi conditionals or `&&' and '||'
2112 constructs ("shell scripts").
2114 If undefined, you get the old, much simpler behaviour
2115 with a somewhat smaller memory footprint.
2118 CONFIG_SYS_PROMPT_HUSH_PS2
2120 This defines the secondary prompt string, which is
2121 printed when the command interpreter needs more input
2122 to complete a command. Usually "> ".
2124 Note:
2126 In the current implementation, the local variables
2127 space and global environment variables space are
2128 separated. Local variables are those you define by
2129 simply typing `name=value'. To access a local
2130 variable later on, you have write `$name' or
2131 `${name}'; to execute the contents of a variable
2132 directly type `$name' at the command prompt.
2134 Global environment variables are those you use
2135 setenv/printenv to work with. To run a command stored
2136 in such a variable, you need to use the run command,
2137 and you must not use the '$' sign to access them.
2139 To store commands and special characters in a
2140 variable, please use double quotation marks
2141 surrounding the whole text of the variable, instead
2142 of the backslashes before semicolons and special
2143 symbols.
2145 - Commandline Editing and History:
2146 CONFIG_CMDLINE_EDITING
2148 Enable editing and History functions for interactive
2149 commandline input operations
2151 - Default Environment:
2152 CONFIG_EXTRA_ENV_SETTINGS
2154 Define this to contain any number of null terminated
2155 strings (variable = value pairs) that will be part of
2156 the default environment compiled into the boot image.
2158 For example, place something like this in your
2159 board's config file:
2161 #define CONFIG_EXTRA_ENV_SETTINGS \
2162 "myvar1=value1\0" \
2163 "myvar2=value2\0"
2165 Warning: This method is based on knowledge about the
2166 internal format how the environment is stored by the
2167 U-Boot code. This is NOT an official, exported
2168 interface! Although it is unlikely that this format
2169 will change soon, there is no guarantee either.
2170 You better know what you are doing here.
2172 Note: overly (ab)use of the default environment is
2173 discouraged. Make sure to check other ways to preset
2174 the environment like the "source" command or the
2175 boot command first.
2177 - DataFlash Support:
2178 CONFIG_HAS_DATAFLASH
2180 Defining this option enables DataFlash features and
2181 allows to read/write in Dataflash via the standard
2182 commands cp, md...
2184 - Serial Flash support
2185 CONFIG_CMD_SF
2187 Defining this option enables SPI flash commands
2188 'sf probe/read/write/erase/update'.
2190 Usage requires an initial 'probe' to define the serial
2191 flash parameters, followed by read/write/erase/update
2192 commands.
2194 The following defaults may be provided by the platform
2195 to handle the common case when only a single serial
2196 flash is present on the system.
2198 CONFIG_SF_DEFAULT_BUS Bus identifier
2199 CONFIG_SF_DEFAULT_CS Chip-select
2200 CONFIG_SF_DEFAULT_MODE (see include/spi.h)
2201 CONFIG_SF_DEFAULT_SPEED in Hz
2203 - SystemACE Support:
2204 CONFIG_SYSTEMACE
2206 Adding this option adds support for Xilinx SystemACE
2207 chips attached via some sort of local bus. The address
2208 of the chip must also be defined in the
2209 CONFIG_SYS_SYSTEMACE_BASE macro. For example:
2211 #define CONFIG_SYSTEMACE
2212 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000
2214 When SystemACE support is added, the "ace" device type
2215 becomes available to the fat commands, i.e. fatls.
2217 - TFTP Fixed UDP Port:
2218 CONFIG_TFTP_PORT
2220 If this is defined, the environment variable tftpsrcp
2221 is used to supply the TFTP UDP source port value.
2222 If tftpsrcp isn't defined, the normal pseudo-random port
2223 number generator is used.
2225 Also, the environment variable tftpdstp is used to supply
2226 the TFTP UDP destination port value. If tftpdstp isn't
2227 defined, the normal port 69 is used.
2229 The purpose for tftpsrcp is to allow a TFTP server to
2230 blindly start the TFTP transfer using the pre-configured
2231 target IP address and UDP port. This has the effect of
2232 "punching through" the (Windows XP) firewall, allowing
2233 the remainder of the TFTP transfer to proceed normally.
2234 A better solution is to properly configure the firewall,
2235 but sometimes that is not allowed.
2237 - Show boot progress:
2238 CONFIG_SHOW_BOOT_PROGRESS
2240 Defining this option allows to add some board-
2241 specific code (calling a user-provided function
2242 "show_boot_progress(int)") that enables you to show
2243 the system's boot progress on some display (for
2244 example, some LED's) on your board. At the moment,
2245 the following checkpoints are implemented:
2247 - Detailed boot stage timing
2248 CONFIG_BOOTSTAGE
2249 Define this option to get detailed timing of each stage
2250 of the boot process.
2252 CONFIG_BOOTSTAGE_USER_COUNT
2253 This is the number of available user bootstage records.
2254 Each time you call bootstage_mark(BOOTSTAGE_ID_ALLOC, ...)
2255 a new ID will be allocated from this stash. If you exceed
2256 the limit, recording will stop.
2258 CONFIG_BOOTSTAGE_REPORT
2259 Define this to print a report before boot, similar to this:
2261 Timer summary in microseconds:
2262 Mark Elapsed Stage
2263 0 0 reset
2264 3,575,678 3,575,678 board_init_f start
2265 3,575,695 17 arch_cpu_init A9
2266 3,575,777 82 arch_cpu_init done
2267 3,659,598 83,821 board_init_r start
2268 3,910,375 250,777 main_loop
2269 29,916,167 26,005,792 bootm_start
2270 30,361,327 445,160 start_kernel
2272 Legacy uImage format:
2274 Arg Where When
2275 1 common/cmd_bootm.c before attempting to boot an image
2276 -1 common/cmd_bootm.c Image header has bad magic number
2277 2 common/cmd_bootm.c Image header has correct magic number
2278 -2 common/cmd_bootm.c Image header has bad checksum
2279 3 common/cmd_bootm.c Image header has correct checksum
2280 -3 common/cmd_bootm.c Image data has bad checksum
2281 4 common/cmd_bootm.c Image data has correct checksum
2282 -4 common/cmd_bootm.c Image is for unsupported architecture
2283 5 common/cmd_bootm.c Architecture check OK
2284 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi)
2285 6 common/cmd_bootm.c Image Type check OK
2286 -6 common/cmd_bootm.c gunzip uncompression error
2287 -7 common/cmd_bootm.c Unimplemented compression type
2288 7 common/cmd_bootm.c Uncompression OK
2289 8 common/cmd_bootm.c No uncompress/copy overwrite error
2290 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
2292 9 common/image.c Start initial ramdisk verification
2293 -10 common/image.c Ramdisk header has bad magic number
2294 -11 common/image.c Ramdisk header has bad checksum
2295 10 common/image.c Ramdisk header is OK
2296 -12 common/image.c Ramdisk data has bad checksum
2297 11 common/image.c Ramdisk data has correct checksum
2298 12 common/image.c Ramdisk verification complete, start loading
2299 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk)
2300 13 common/image.c Start multifile image verification
2301 14 common/image.c No initial ramdisk, no multifile, continue.
2303 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS
2305 -30 arch/powerpc/lib/board.c Fatal error, hang the system
2306 -31 post/post.c POST test failed, detected by post_output_backlog()
2307 -32 post/post.c POST test failed, detected by post_run_single()
2309 34 common/cmd_doc.c before loading a Image from a DOC device
2310 -35 common/cmd_doc.c Bad usage of "doc" command
2311 35 common/cmd_doc.c correct usage of "doc" command
2312 -36 common/cmd_doc.c No boot device
2313 36 common/cmd_doc.c correct boot device
2314 -37 common/cmd_doc.c Unknown Chip ID on boot device
2315 37 common/cmd_doc.c correct chip ID found, device available
2316 -38 common/cmd_doc.c Read Error on boot device
2317 38 common/cmd_doc.c reading Image header from DOC device OK
2318 -39 common/cmd_doc.c Image header has bad magic number
2319 39 common/cmd_doc.c Image header has correct magic number
2320 -40 common/cmd_doc.c Error reading Image from DOC device
2321 40 common/cmd_doc.c Image header has correct magic number
2322 41 common/cmd_ide.c before loading a Image from a IDE device
2323 -42 common/cmd_ide.c Bad usage of "ide" command
2324 42 common/cmd_ide.c correct usage of "ide" command
2325 -43 common/cmd_ide.c No boot device
2326 43 common/cmd_ide.c boot device found
2327 -44 common/cmd_ide.c Device not available
2328 44 common/cmd_ide.c Device available
2329 -45 common/cmd_ide.c wrong partition selected
2330 45 common/cmd_ide.c partition selected
2331 -46 common/cmd_ide.c Unknown partition table
2332 46 common/cmd_ide.c valid partition table found
2333 -47 common/cmd_ide.c Invalid partition type
2334 47 common/cmd_ide.c correct partition type
2335 -48 common/cmd_ide.c Error reading Image Header on boot device
2336 48 common/cmd_ide.c reading Image Header from IDE device OK
2337 -49 common/cmd_ide.c Image header has bad magic number
2338 49 common/cmd_ide.c Image header has correct magic number
2339 -50 common/cmd_ide.c Image header has bad checksum
2340 50 common/cmd_ide.c Image header has correct checksum
2341 -51 common/cmd_ide.c Error reading Image from IDE device
2342 51 common/cmd_ide.c reading Image from IDE device OK
2343 52 common/cmd_nand.c before loading a Image from a NAND device
2344 -53 common/cmd_nand.c Bad usage of "nand" command
2345 53 common/cmd_nand.c correct usage of "nand" command
2346 -54 common/cmd_nand.c No boot device
2347 54 common/cmd_nand.c boot device found
2348 -55 common/cmd_nand.c Unknown Chip ID on boot device
2349 55 common/cmd_nand.c correct chip ID found, device available
2350 -56 common/cmd_nand.c Error reading Image Header on boot device
2351 56 common/cmd_nand.c reading Image Header from NAND device OK
2352 -57 common/cmd_nand.c Image header has bad magic number
2353 57 common/cmd_nand.c Image header has correct magic number
2354 -58 common/cmd_nand.c Error reading Image from NAND device
2355 58 common/cmd_nand.c reading Image from NAND device OK
2357 -60 common/env_common.c Environment has a bad CRC, using default
2359 64 net/eth.c starting with Ethernet configuration.
2360 -64 net/eth.c no Ethernet found.
2361 65 net/eth.c Ethernet found.
2363 -80 common/cmd_net.c usage wrong
2364 80 common/cmd_net.c before calling NetLoop()
2365 -81 common/cmd_net.c some error in NetLoop() occurred
2366 81 common/cmd_net.c NetLoop() back without error
2367 -82 common/cmd_net.c size == 0 (File with size 0 loaded)
2368 82 common/cmd_net.c trying automatic boot
2369 83 common/cmd_net.c running "source" command
2370 -83 common/cmd_net.c some error in automatic boot or "source" command
2371 84 common/cmd_net.c end without errors
2373 FIT uImage format:
2375 Arg Where When
2376 100 common/cmd_bootm.c Kernel FIT Image has correct format
2377 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format
2378 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration
2379 -101 common/cmd_bootm.c Can't get configuration for kernel subimage
2380 102 common/cmd_bootm.c Kernel unit name specified
2381 -103 common/cmd_bootm.c Can't get kernel subimage node offset
2382 103 common/cmd_bootm.c Found configuration node
2383 104 common/cmd_bootm.c Got kernel subimage node offset
2384 -104 common/cmd_bootm.c Kernel subimage hash verification failed
2385 105 common/cmd_bootm.c Kernel subimage hash verification OK
2386 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture
2387 106 common/cmd_bootm.c Architecture check OK
2388 -106 common/cmd_bootm.c Kernel subimage has wrong type
2389 107 common/cmd_bootm.c Kernel subimage type OK
2390 -107 common/cmd_bootm.c Can't get kernel subimage data/size
2391 108 common/cmd_bootm.c Got kernel subimage data/size
2392 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT)
2393 -109 common/cmd_bootm.c Can't get kernel subimage type
2394 -110 common/cmd_bootm.c Can't get kernel subimage comp
2395 -111 common/cmd_bootm.c Can't get kernel subimage os
2396 -112 common/cmd_bootm.c Can't get kernel subimage load address
2397 -113 common/cmd_bootm.c Image uncompress/copy overwrite error
2399 120 common/image.c Start initial ramdisk verification
2400 -120 common/image.c Ramdisk FIT image has incorrect format
2401 121 common/image.c Ramdisk FIT image has correct format
2402 122 common/image.c No ramdisk subimage unit name, using configuration
2403 -122 common/image.c Can't get configuration for ramdisk subimage
2404 123 common/image.c Ramdisk unit name specified
2405 -124 common/image.c Can't get ramdisk subimage node offset
2406 125 common/image.c Got ramdisk subimage node offset
2407 -125 common/image.c Ramdisk subimage hash verification failed
2408 126 common/image.c Ramdisk subimage hash verification OK
2409 -126 common/image.c Ramdisk subimage for unsupported architecture
2410 127 common/image.c Architecture check OK
2411 -127 common/image.c Can't get ramdisk subimage data/size
2412 128 common/image.c Got ramdisk subimage data/size
2413 129 common/image.c Can't get ramdisk load address
2414 -129 common/image.c Got ramdisk load address
2416 -130 common/cmd_doc.c Incorrect FIT image format
2417 131 common/cmd_doc.c FIT image format OK
2419 -140 common/cmd_ide.c Incorrect FIT image format
2420 141 common/cmd_ide.c FIT image format OK
2422 -150 common/cmd_nand.c Incorrect FIT image format
2423 151 common/cmd_nand.c FIT image format OK
2425 - Standalone program support:
2426 CONFIG_STANDALONE_LOAD_ADDR
2428 This option defines a board specific value for the
2429 address where standalone program gets loaded, thus
2430 overwriting the architecture dependent default
2431 settings.
2433 - Frame Buffer Address:
2434 CONFIG_FB_ADDR
2436 Define CONFIG_FB_ADDR if you want to use specific
2437 address for frame buffer.
2438 Then system will reserve the frame buffer address to
2439 defined address instead of lcd_setmem (this function
2440 grabs the memory for frame buffer by panel's size).
2442 Please see board_init_f function.
2444 - Automatic software updates via TFTP server
2445 CONFIG_UPDATE_TFTP
2446 CONFIG_UPDATE_TFTP_CNT_MAX
2447 CONFIG_UPDATE_TFTP_MSEC_MAX
2449 These options enable and control the auto-update feature;
2450 for a more detailed description refer to doc/README.update.
2452 - MTD Support (mtdparts command, UBI support)
2453 CONFIG_MTD_DEVICE
2455 Adds the MTD device infrastructure from the Linux kernel.
2456 Needed for mtdparts command support.
2458 CONFIG_MTD_PARTITIONS
2460 Adds the MTD partitioning infrastructure from the Linux
2461 kernel. Needed for UBI support.
2463 - SPL framework
2464 CONFIG_SPL
2465 Enable building of SPL globally.
2467 CONFIG_SPL_TEXT_BASE
2468 TEXT_BASE for linking the SPL binary.
2470 CONFIG_SPL_LDSCRIPT
2471 LDSCRIPT for linking the SPL binary.
2473 CONFIG_SPL_LIBCOMMON_SUPPORT
2474 Support for common/libcommon.o in SPL binary
2476 CONFIG_SPL_LIBDISK_SUPPORT
2477 Support for disk/libdisk.o in SPL binary
2479 CONFIG_SPL_I2C_SUPPORT
2480 Support for drivers/i2c/libi2c.o in SPL binary
2482 CONFIG_SPL_GPIO_SUPPORT
2483 Support for drivers/gpio/libgpio.o in SPL binary
2485 CONFIG_SPL_MMC_SUPPORT
2486 Support for drivers/mmc/libmmc.o in SPL binary
2488 CONFIG_SPL_SERIAL_SUPPORT
2489 Support for drivers/serial/libserial.o in SPL binary
2491 CONFIG_SPL_SPI_FLASH_SUPPORT
2492 Support for drivers/mtd/spi/libspi_flash.o in SPL binary
2494 CONFIG_SPL_SPI_SUPPORT
2495 Support for drivers/spi/libspi.o in SPL binary
2497 CONFIG_SPL_FAT_SUPPORT
2498 Support for fs/fat/libfat.o in SPL binary
2500 CONFIG_SPL_LIBGENERIC_SUPPORT
2501 Support for lib/libgeneric.o in SPL binary
2503 Modem Support:
2504 --------------
2506 [so far only for SMDK2400 boards]
2508 - Modem support enable:
2509 CONFIG_MODEM_SUPPORT
2511 - RTS/CTS Flow control enable:
2512 CONFIG_HWFLOW
2514 - Modem debug support:
2515 CONFIG_MODEM_SUPPORT_DEBUG
2517 Enables debugging stuff (char screen[1024], dbg())
2518 for modem support. Useful only with BDI2000.
2520 - Interrupt support (PPC):
2522 There are common interrupt_init() and timer_interrupt()
2523 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
2524 for CPU specific initialization. interrupt_init_cpu()
2525 should set decrementer_count to appropriate value. If
2526 CPU resets decrementer automatically after interrupt
2527 (ppc4xx) it should set decrementer_count to zero.
2528 timer_interrupt() calls timer_interrupt_cpu() for CPU
2529 specific handling. If board has watchdog / status_led
2530 / other_activity_monitor it works automatically from
2531 general timer_interrupt().
2533 - General:
2535 In the target system modem support is enabled when a
2536 specific key (key combination) is pressed during
2537 power-on. Otherwise U-Boot will boot normally
2538 (autoboot). The key_pressed() function is called from
2539 board_init(). Currently key_pressed() is a dummy
2540 function, returning 1 and thus enabling modem
2541 initialization.
2543 If there are no modem init strings in the
2544 environment, U-Boot proceed to autoboot; the
2545 previous output (banner, info printfs) will be
2546 suppressed, though.
2548 See also: doc/README.Modem
2550 Board initialization settings:
2551 ------------------------------
2553 During Initialization u-boot calls a number of board specific functions
2554 to allow the preparation of board specific prerequisites, e.g. pin setup
2555 before drivers are initialized. To enable these callbacks the
2556 following configuration macros have to be defined. Currently this is
2557 architecture specific, so please check arch/your_architecture/lib/board.c
2558 typically in board_init_f() and board_init_r().
2560 - CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f()
2561 - CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r()
2562 - CONFIG_BOARD_LATE_INIT: Call board_late_init()
2563 - CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init()
2565 Configuration Settings:
2566 -----------------------
2568 - CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
2569 undefine this when you're short of memory.
2571 - CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
2572 width of the commands listed in the 'help' command output.
2574 - CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to
2575 prompt for user input.
2577 - CONFIG_SYS_CBSIZE: Buffer size for input from the Console
2579 - CONFIG_SYS_PBSIZE: Buffer size for Console output
2581 - CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands
2583 - CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to
2584 the application (usually a Linux kernel) when it is
2585 booted
2587 - CONFIG_SYS_BAUDRATE_TABLE:
2588 List of legal baudrate settings for this board.
2590 - CONFIG_SYS_CONSOLE_INFO_QUIET
2591 Suppress display of console information at boot.
2593 - CONFIG_SYS_CONSOLE_IS_IN_ENV
2594 If the board specific function
2595 extern int overwrite_console (void);
2596 returns 1, the stdin, stderr and stdout are switched to the
2597 serial port, else the settings in the environment are used.
2599 - CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE
2600 Enable the call to overwrite_console().
2602 - CONFIG_SYS_CONSOLE_ENV_OVERWRITE
2603 Enable overwrite of previous console environment settings.
2605 - CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END:
2606 Begin and End addresses of the area used by the
2607 simple memory test.
2609 - CONFIG_SYS_ALT_MEMTEST:
2610 Enable an alternate, more extensive memory test.
2612 - CONFIG_SYS_MEMTEST_SCRATCH:
2613 Scratch address used by the alternate memory test
2614 You only need to set this if address zero isn't writeable
2616 - CONFIG_SYS_MEM_TOP_HIDE (PPC only):
2617 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header,
2618 this specified memory area will get subtracted from the top
2619 (end) of RAM and won't get "touched" at all by U-Boot. By
2620 fixing up gd->ram_size the Linux kernel should gets passed
2621 the now "corrected" memory size and won't touch it either.
2622 This should work for arch/ppc and arch/powerpc. Only Linux
2623 board ports in arch/powerpc with bootwrapper support that
2624 recalculate the memory size from the SDRAM controller setup
2625 will have to get fixed in Linux additionally.
2627 This option can be used as a workaround for the 440EPx/GRx
2628 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't
2629 be touched.
2631 WARNING: Please make sure that this value is a multiple of
2632 the Linux page size (normally 4k). If this is not the case,
2633 then the end address of the Linux memory will be located at a
2634 non page size aligned address and this could cause major
2635 problems.
2637 - CONFIG_SYS_TFTP_LOADADDR:
2638 Default load address for network file downloads
2640 - CONFIG_SYS_LOADS_BAUD_CHANGE:
2641 Enable temporary baudrate change while serial download
2643 - CONFIG_SYS_SDRAM_BASE:
2644 Physical start address of SDRAM. _Must_ be 0 here.
2646 - CONFIG_SYS_MBIO_BASE:
2647 Physical start address of Motherboard I/O (if using a
2648 Cogent motherboard)
2650 - CONFIG_SYS_FLASH_BASE:
2651 Physical start address of Flash memory.
2653 - CONFIG_SYS_MONITOR_BASE:
2654 Physical start address of boot monitor code (set by
2655 make config files to be same as the text base address
2656 (CONFIG_SYS_TEXT_BASE) used when linking) - same as
2657 CONFIG_SYS_FLASH_BASE when booting from flash.
2659 - CONFIG_SYS_MONITOR_LEN:
2660 Size of memory reserved for monitor code, used to
2661 determine _at_compile_time_ (!) if the environment is
2662 embedded within the U-Boot image, or in a separate
2663 flash sector.
2665 - CONFIG_SYS_MALLOC_LEN:
2666 Size of DRAM reserved for malloc() use.
2668 - CONFIG_SYS_BOOTM_LEN:
2669 Normally compressed uImages are limited to an
2670 uncompressed size of 8 MBytes. If this is not enough,
2671 you can define CONFIG_SYS_BOOTM_LEN in your board config file
2672 to adjust this setting to your needs.
2674 - CONFIG_SYS_BOOTMAPSZ:
2675 Maximum size of memory mapped by the startup code of
2676 the Linux kernel; all data that must be processed by
2677 the Linux kernel (bd_info, boot arguments, FDT blob if
2678 used) must be put below this limit, unless "bootm_low"
2679 enviroment variable is defined and non-zero. In such case
2680 all data for the Linux kernel must be between "bootm_low"
2681 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment
2682 variable "bootm_mapsize" will override the value of
2683 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined,
2684 then the value in "bootm_size" will be used instead.
2686 - CONFIG_SYS_BOOT_RAMDISK_HIGH:
2687 Enable initrd_high functionality. If defined then the
2688 initrd_high feature is enabled and the bootm ramdisk subcommand
2689 is enabled.
2691 - CONFIG_SYS_BOOT_GET_CMDLINE:
2692 Enables allocating and saving kernel cmdline in space between
2693 "bootm_low" and "bootm_low" + BOOTMAPSZ.
2695 - CONFIG_SYS_BOOT_GET_KBD:
2696 Enables allocating and saving a kernel copy of the bd_info in
2697 space between "bootm_low" and "bootm_low" + BOOTMAPSZ.
2699 - CONFIG_SYS_MAX_FLASH_BANKS:
2700 Max number of Flash memory banks
2702 - CONFIG_SYS_MAX_FLASH_SECT:
2703 Max number of sectors on a Flash chip
2705 - CONFIG_SYS_FLASH_ERASE_TOUT:
2706 Timeout for Flash erase operations (in ms)
2708 - CONFIG_SYS_FLASH_WRITE_TOUT:
2709 Timeout for Flash write operations (in ms)
2711 - CONFIG_SYS_FLASH_LOCK_TOUT
2712 Timeout for Flash set sector lock bit operation (in ms)
2714 - CONFIG_SYS_FLASH_UNLOCK_TOUT
2715 Timeout for Flash clear lock bits operation (in ms)
2717 - CONFIG_SYS_FLASH_PROTECTION
2718 If defined, hardware flash sectors protection is used
2719 instead of U-Boot software protection.
2721 - CONFIG_SYS_DIRECT_FLASH_TFTP:
2723 Enable TFTP transfers directly to flash memory;
2724 without this option such a download has to be
2725 performed in two steps: (1) download to RAM, and (2)
2726 copy from RAM to flash.
2728 The two-step approach is usually more reliable, since
2729 you can check if the download worked before you erase
2730 the flash, but in some situations (when system RAM is
2731 too limited to allow for a temporary copy of the
2732 downloaded image) this option may be very useful.
2734 - CONFIG_SYS_FLASH_CFI:
2735 Define if the flash driver uses extra elements in the
2736 common flash structure for storing flash geometry.
2738 - CONFIG_FLASH_CFI_DRIVER
2739 This option also enables the building of the cfi_flash driver
2740 in the drivers directory
2742 - CONFIG_FLASH_CFI_MTD
2743 This option enables the building of the cfi_mtd driver
2744 in the drivers directory. The driver exports CFI flash
2745 to the MTD layer.
2747 - CONFIG_SYS_FLASH_USE_BUFFER_WRITE
2748 Use buffered writes to flash.
2750 - CONFIG_FLASH_SPANSION_S29WS_N
2751 s29ws-n MirrorBit flash has non-standard addresses for buffered
2752 write commands.
2754 - CONFIG_SYS_FLASH_QUIET_TEST
2755 If this option is defined, the common CFI flash doesn't
2756 print it's warning upon not recognized FLASH banks. This
2757 is useful, if some of the configured banks are only
2758 optionally available.
2760 - CONFIG_FLASH_SHOW_PROGRESS
2761 If defined (must be an integer), print out countdown
2762 digits and dots. Recommended value: 45 (9..1) for 80
2763 column displays, 15 (3..1) for 40 column displays.
2765 - CONFIG_SYS_RX_ETH_BUFFER:
2766 Defines the number of Ethernet receive buffers. On some
2767 Ethernet controllers it is recommended to set this value
2768 to 8 or even higher (EEPRO100 or 405 EMAC), since all
2769 buffers can be full shortly after enabling the interface
2770 on high Ethernet traffic.
2771 Defaults to 4 if not defined.
2773 - CONFIG_ENV_MAX_ENTRIES
2775 Maximum number of entries in the hash table that is used
2776 internally to store the environment settings. The default
2777 setting is supposed to be generous and should work in most
2778 cases. This setting can be used to tune behaviour; see
2779 lib/hashtable.c for details.
2781 The following definitions that deal with the placement and management
2782 of environment data (variable area); in general, we support the
2783 following configurations:
2785 - CONFIG_BUILD_ENVCRC:
2787 Builds up envcrc with the target environment so that external utils
2788 may easily extract it and embed it in final U-Boot images.
2790 - CONFIG_ENV_IS_IN_FLASH:
2792 Define this if the environment is in flash memory.
2794 a) The environment occupies one whole flash sector, which is
2795 "embedded" in the text segment with the U-Boot code. This
2796 happens usually with "bottom boot sector" or "top boot
2797 sector" type flash chips, which have several smaller
2798 sectors at the start or the end. For instance, such a
2799 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
2800 such a case you would place the environment in one of the
2801 4 kB sectors - with U-Boot code before and after it. With
2802 "top boot sector" type flash chips, you would put the
2803 environment in one of the last sectors, leaving a gap
2804 between U-Boot and the environment.
2806 - CONFIG_ENV_OFFSET:
2808 Offset of environment data (variable area) to the
2809 beginning of flash memory; for instance, with bottom boot
2810 type flash chips the second sector can be used: the offset
2811 for this sector is given here.
2813 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE.
2815 - CONFIG_ENV_ADDR:
2817 This is just another way to specify the start address of
2818 the flash sector containing the environment (instead of
2819 CONFIG_ENV_OFFSET).
2821 - CONFIG_ENV_SECT_SIZE:
2823 Size of the sector containing the environment.
2826 b) Sometimes flash chips have few, equal sized, BIG sectors.
2827 In such a case you don't want to spend a whole sector for
2828 the environment.
2830 - CONFIG_ENV_SIZE:
2832 If you use this in combination with CONFIG_ENV_IS_IN_FLASH
2833 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part
2834 of this flash sector for the environment. This saves
2835 memory for the RAM copy of the environment.
2837 It may also save flash memory if you decide to use this
2838 when your environment is "embedded" within U-Boot code,
2839 since then the remainder of the flash sector could be used
2840 for U-Boot code. It should be pointed out that this is
2841 STRONGLY DISCOURAGED from a robustness point of view:
2842 updating the environment in flash makes it always
2843 necessary to erase the WHOLE sector. If something goes
2844 wrong before the contents has been restored from a copy in
2845 RAM, your target system will be dead.
2847 - CONFIG_ENV_ADDR_REDUND
2848 CONFIG_ENV_SIZE_REDUND
2850 These settings describe a second storage area used to hold
2851 a redundant copy of the environment data, so that there is
2852 a valid backup copy in case there is a power failure during
2853 a "saveenv" operation.
2855 BE CAREFUL! Any changes to the flash layout, and some changes to the
2856 source code will make it necessary to adapt <board>/u-boot.lds*
2857 accordingly!
2860 - CONFIG_ENV_IS_IN_NVRAM:
2862 Define this if you have some non-volatile memory device
2863 (NVRAM, battery buffered SRAM) which you want to use for the
2864 environment.
2866 - CONFIG_ENV_ADDR:
2867 - CONFIG_ENV_SIZE:
2869 These two #defines are used to determine the memory area you
2870 want to use for environment. It is assumed that this memory
2871 can just be read and written to, without any special
2872 provision.
2874 BE CAREFUL! The first access to the environment happens quite early
2875 in U-Boot initalization (when we try to get the setting of for the
2876 console baudrate). You *MUST* have mapped your NVRAM area then, or
2877 U-Boot will hang.
2879 Please note that even with NVRAM we still use a copy of the
2880 environment in RAM: we could work on NVRAM directly, but we want to
2881 keep settings there always unmodified except somebody uses "saveenv"
2882 to save the current settings.
2885 - CONFIG_ENV_IS_IN_EEPROM:
2887 Use this if you have an EEPROM or similar serial access
2888 device and a driver for it.
2890 - CONFIG_ENV_OFFSET:
2891 - CONFIG_ENV_SIZE:
2893 These two #defines specify the offset and size of the
2894 environment area within the total memory of your EEPROM.
2896 - CONFIG_SYS_I2C_EEPROM_ADDR:
2897 If defined, specified the chip address of the EEPROM device.
2898 The default address is zero.
2900 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS:
2901 If defined, the number of bits used to address bytes in a
2902 single page in the EEPROM device. A 64 byte page, for example
2903 would require six bits.
2905 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS:
2906 If defined, the number of milliseconds to delay between
2907 page writes. The default is zero milliseconds.
2909 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN:
2910 The length in bytes of the EEPROM memory array address. Note
2911 that this is NOT the chip address length!
2913 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW:
2914 EEPROM chips that implement "address overflow" are ones
2915 like Catalyst 24WC04/08/16 which has 9/10/11 bits of
2916 address and the extra bits end up in the "chip address" bit
2917 slots. This makes a 24WC08 (1Kbyte) chip look like four 256
2918 byte chips.
2920 Note that we consider the length of the address field to
2921 still be one byte because the extra address bits are hidden
2922 in the chip address.
2924 - CONFIG_SYS_EEPROM_SIZE:
2925 The size in bytes of the EEPROM device.
2927 - CONFIG_ENV_EEPROM_IS_ON_I2C
2928 define this, if you have I2C and SPI activated, and your
2929 EEPROM, which holds the environment, is on the I2C bus.
2931 - CONFIG_I2C_ENV_EEPROM_BUS
2932 if you have an Environment on an EEPROM reached over
2933 I2C muxes, you can define here, how to reach this
2934 EEPROM. For example:
2936 #define CONFIG_I2C_ENV_EEPROM_BUS "pca9547:70:d\0"
2938 EEPROM which holds the environment, is reached over
2939 a pca9547 i2c mux with address 0x70, channel 3.
2941 - CONFIG_ENV_IS_IN_DATAFLASH:
2943 Define this if you have a DataFlash memory device which you
2944 want to use for the environment.
2946 - CONFIG_ENV_OFFSET:
2947 - CONFIG_ENV_ADDR:
2948 - CONFIG_ENV_SIZE:
2950 These three #defines specify the offset and size of the
2951 environment area within the total memory of your DataFlash placed
2952 at the specified address.
2954 - CONFIG_ENV_IS_IN_NAND:
2956 Define this if you have a NAND device which you want to use
2957 for the environment.
2959 - CONFIG_ENV_OFFSET:
2960 - CONFIG_ENV_SIZE:
2962 These two #defines specify the offset and size of the environment
2963 area within the first NAND device. CONFIG_ENV_OFFSET must be
2964 aligned to an erase block boundary.
2966 - CONFIG_ENV_OFFSET_REDUND (optional):
2968 This setting describes a second storage area of CONFIG_ENV_SIZE
2969 size used to hold a redundant copy of the environment data, so
2970 that there is a valid backup copy in case there is a power failure
2971 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be
2972 aligned to an erase block boundary.
2974 - CONFIG_ENV_RANGE (optional):
2976 Specifies the length of the region in which the environment
2977 can be written. This should be a multiple of the NAND device's
2978 block size. Specifying a range with more erase blocks than
2979 are needed to hold CONFIG_ENV_SIZE allows bad blocks within
2980 the range to be avoided.
2982 - CONFIG_ENV_OFFSET_OOB (optional):
2984 Enables support for dynamically retrieving the offset of the
2985 environment from block zero's out-of-band data. The
2986 "nand env.oob" command can be used to record this offset.
2987 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when
2988 using CONFIG_ENV_OFFSET_OOB.
2990 - CONFIG_NAND_ENV_DST
2992 Defines address in RAM to which the nand_spl code should copy the
2993 environment. If redundant environment is used, it will be copied to
2994 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE.
2996 - CONFIG_SYS_SPI_INIT_OFFSET
2998 Defines offset to the initial SPI buffer area in DPRAM. The
2999 area is used at an early stage (ROM part) if the environment
3000 is configured to reside in the SPI EEPROM: We need a 520 byte
3001 scratch DPRAM area. It is used between the two initialization
3002 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
3003 to be a good choice since it makes it far enough from the
3004 start of the data area as well as from the stack pointer.
3006 Please note that the environment is read-only until the monitor
3007 has been relocated to RAM and a RAM copy of the environment has been
3008 created; also, when using EEPROM you will have to use getenv_f()
3009 until then to read environment variables.
3011 The environment is protected by a CRC32 checksum. Before the monitor
3012 is relocated into RAM, as a result of a bad CRC you will be working
3013 with the compiled-in default environment - *silently*!!! [This is
3014 necessary, because the first environment variable we need is the
3015 "baudrate" setting for the console - if we have a bad CRC, we don't
3016 have any device yet where we could complain.]
3018 Note: once the monitor has been relocated, then it will complain if
3019 the default environment is used; a new CRC is computed as soon as you
3020 use the "saveenv" command to store a valid environment.
3022 - CONFIG_SYS_FAULT_ECHO_LINK_DOWN:
3023 Echo the inverted Ethernet link state to the fault LED.
3025 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR
3026 also needs to be defined.
3028 - CONFIG_SYS_FAULT_MII_ADDR:
3029 MII address of the PHY to check for the Ethernet link state.
3031 - CONFIG_NS16550_MIN_FUNCTIONS:
3032 Define this if you desire to only have use of the NS16550_init
3033 and NS16550_putc functions for the serial driver located at
3034 drivers/serial/ns16550.c. This option is useful for saving
3035 space for already greatly restricted images, including but not
3036 limited to NAND_SPL configurations.
3038 Low Level (hardware related) configuration options:
3039 ---------------------------------------------------
3041 - CONFIG_SYS_CACHELINE_SIZE:
3042 Cache Line Size of the CPU.
3044 - CONFIG_SYS_DEFAULT_IMMR:
3045 Default address of the IMMR after system reset.
3047 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
3048 and RPXsuper) to be able to adjust the position of
3049 the IMMR register after a reset.
3051 - CONFIG_SYS_CCSRBAR_DEFAULT:
3052 Default (power-on reset) physical address of CCSR on Freescale
3053 PowerPC SOCs.
3055 - CONFIG_SYS_CCSRBAR:
3056 Virtual address of CCSR. On a 32-bit build, this is typically
3057 the same value as CONFIG_SYS_CCSRBAR_DEFAULT.
3059 CONFIG_SYS_DEFAULT_IMMR must also be set to this value,
3060 for cross-platform code that uses that macro instead.
3062 - CONFIG_SYS_CCSRBAR_PHYS:
3063 Physical address of CCSR. CCSR can be relocated to a new
3064 physical address, if desired. In this case, this macro should
3065 be set to that address. Otherwise, it should be set to the
3066 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR
3067 is typically relocated on 36-bit builds. It is recommended
3068 that this macro be defined via the _HIGH and _LOW macros:
3070 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH
3071 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW)
3073 - CONFIG_SYS_CCSRBAR_PHYS_HIGH:
3074 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically
3075 either 0 (32-bit build) or 0xF (36-bit build). This macro is
3076 used in assembly code, so it must not contain typecasts or
3077 integer size suffixes (e.g. "ULL").
3079 - CONFIG_SYS_CCSRBAR_PHYS_LOW:
3080 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is
3081 used in assembly code, so it must not contain typecasts or
3082 integer size suffixes (e.g. "ULL").
3084 - CONFIG_SYS_CCSR_DO_NOT_RELOCATE:
3085 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be
3086 forced to a value that ensures that CCSR is not relocated.
3088 - Floppy Disk Support:
3089 CONFIG_SYS_FDC_DRIVE_NUMBER
3091 the default drive number (default value 0)
3093 CONFIG_SYS_ISA_IO_STRIDE
3095 defines the spacing between FDC chipset registers
3096 (default value 1)
3098 CONFIG_SYS_ISA_IO_OFFSET
3100 defines the offset of register from address. It
3101 depends on which part of the data bus is connected to
3102 the FDC chipset. (default value 0)
3104 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and
3105 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their
3106 default value.
3108 if CONFIG_SYS_FDC_HW_INIT is defined, then the function
3109 fdc_hw_init() is called at the beginning of the FDC
3110 setup. fdc_hw_init() must be provided by the board
3111 source code. It is used to make hardware dependant
3112 initializations.
3114 - CONFIG_IDE_AHB:
3115 Most IDE controllers were designed to be connected with PCI
3116 interface. Only few of them were designed for AHB interface.
3117 When software is doing ATA command and data transfer to
3118 IDE devices through IDE-AHB controller, some additional
3119 registers accessing to these kind of IDE-AHB controller
3120 is requierd.
3122 - CONFIG_SYS_IMMR: Physical address of the Internal Memory.
3123 DO NOT CHANGE unless you know exactly what you're
3124 doing! (11-4) [MPC8xx/82xx systems only]
3126 - CONFIG_SYS_INIT_RAM_ADDR:
3128 Start address of memory area that can be used for
3129 initial data and stack; please note that this must be
3130 writable memory that is working WITHOUT special
3131 initialization, i. e. you CANNOT use normal RAM which
3132 will become available only after programming the
3133 memory controller and running certain initialization
3134 sequences.
3136 U-Boot uses the following memory types:
3137 - MPC8xx and MPC8260: IMMR (internal memory of the CPU)
3138 - MPC824X: data cache
3139 - PPC4xx: data cache
3141 - CONFIG_SYS_GBL_DATA_OFFSET:
3143 Offset of the initial data structure in the memory
3144 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually
3145 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial
3146 data is located at the end of the available space
3147 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE -
3148 CONFIG_SYS_INIT_DATA_SIZE), and the initial stack is just
3149 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR +
3150 CONFIG_SYS_GBL_DATA_OFFSET) downward.
3152 Note:
3153 On the MPC824X (or other systems that use the data
3154 cache for initial memory) the address chosen for
3155 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must
3156 point to an otherwise UNUSED address space between
3157 the top of RAM and the start of the PCI space.
3159 - CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6)
3161 - CONFIG_SYS_SYPCR: System Protection Control (11-9)
3163 - CONFIG_SYS_TBSCR: Time Base Status and Control (11-26)
3165 - CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31)
3167 - CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30)
3169 - CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27)
3171 - CONFIG_SYS_OR_TIMING_SDRAM:
3172 SDRAM timing
3174 - CONFIG_SYS_MAMR_PTA:
3175 periodic timer for refresh
3177 - CONFIG_SYS_DER: Debug Event Register (37-47)
3179 - FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM,
3180 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP,
3181 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM,
3182 CONFIG_SYS_BR1_PRELIM:
3183 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
3185 - SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
3186 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM,
3187 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM:
3188 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
3190 - CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K,
3191 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL:
3192 Machine Mode Register and Memory Periodic Timer
3193 Prescaler definitions (SDRAM timing)
3195 - CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]:
3196 enable I2C microcode relocation patch (MPC8xx);
3197 define relocation offset in DPRAM [DSP2]
3199 - CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]:
3200 enable SMC microcode relocation patch (MPC8xx);
3201 define relocation offset in DPRAM [SMC1]
3203 - CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]:
3204 enable SPI microcode relocation patch (MPC8xx);
3205 define relocation offset in DPRAM [SCC4]
3207 - CONFIG_SYS_USE_OSCCLK:
3208 Use OSCM clock mode on MBX8xx board. Be careful,
3209 wrong setting might damage your board. Read
3210 doc/README.MBX before setting this variable!
3212 - CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
3213 Offset of the bootmode word in DPRAM used by post
3214 (Power On Self Tests). This definition overrides
3215 #define'd default value in commproc.h resp.
3216 cpm_8260.h.
3218 - CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB,
3219 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL,
3220 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS,
3221 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB,
3222 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
3223 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL,
3224 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE,
3225 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only)
3226 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set.
3228 - CONFIG_PCI_DISABLE_PCIE:
3229 Disable PCI-Express on systems where it is supported but not
3230 required.
3232 - CONFIG_SYS_SRIO:
3233 Chip has SRIO or not
3235 - CONFIG_SRIO1:
3236 Board has SRIO 1 port available
3238 - CONFIG_SRIO2:
3239 Board has SRIO 2 port available
3241 - CONFIG_SYS_SRIOn_MEM_VIRT:
3242 Virtual Address of SRIO port 'n' memory region
3244 - CONFIG_SYS_SRIOn_MEM_PHYS:
3245 Physical Address of SRIO port 'n' memory region
3247 - CONFIG_SYS_SRIOn_MEM_SIZE:
3248 Size of SRIO port 'n' memory region
3250 - CONFIG_SYS_NDFC_16
3251 Defined to tell the NDFC that the NAND chip is using a
3252 16 bit bus.
3254 - CONFIG_SYS_NDFC_EBC0_CFG
3255 Sets the EBC0_CFG register for the NDFC. If not defined
3256 a default value will be used.
3258 - CONFIG_SPD_EEPROM
3259 Get DDR timing information from an I2C EEPROM. Common
3260 with pluggable memory modules such as SODIMMs
3262 SPD_EEPROM_ADDRESS
3263 I2C address of the SPD EEPROM
3265 - CONFIG_SYS_SPD_BUS_NUM
3266 If SPD EEPROM is on an I2C bus other than the first
3267 one, specify here. Note that the value must resolve
3268 to something your driver can deal with.
3270 - CONFIG_SYS_DDR_RAW_TIMING
3271 Get DDR timing information from other than SPD. Common with
3272 soldered DDR chips onboard without SPD. DDR raw timing
3273 parameters are extracted from datasheet and hard-coded into
3274 header files or board specific files.
3276 - CONFIG_FSL_DDR_INTERACTIVE
3277 Enable interactive DDR debugging. See doc/README.fsl-ddr.
3279 - CONFIG_SYS_83XX_DDR_USES_CS0
3280 Only for 83xx systems. If specified, then DDR should
3281 be configured using CS0 and CS1 instead of CS2 and CS3.
3283 - CONFIG_ETHER_ON_FEC[12]
3284 Define to enable FEC[12] on a 8xx series processor.
3286 - CONFIG_FEC[12]_PHY
3287 Define to the hardcoded PHY address which corresponds
3288 to the given FEC; i. e.
3289 #define CONFIG_FEC1_PHY 4
3290 means that the PHY with address 4 is connected to FEC1
3292 When set to -1, means to probe for first available.
3294 - CONFIG_FEC[12]_PHY_NORXERR
3295 The PHY does not have a RXERR line (RMII only).
3296 (so program the FEC to ignore it).
3298 - CONFIG_RMII
3299 Enable RMII mode for all FECs.
3300 Note that this is a global option, we can't
3301 have one FEC in standard MII mode and another in RMII mode.
3303 - CONFIG_CRC32_VERIFY
3304 Add a verify option to the crc32 command.
3305 The syntax is:
3307 => crc32 -v <address> <count> <crc32>
3309 Where address/count indicate a memory area
3310 and crc32 is the correct crc32 which the
3311 area should have.
3313 - CONFIG_LOOPW
3314 Add the "loopw" memory command. This only takes effect if
3315 the memory commands are activated globally (CONFIG_CMD_MEM).
3317 - CONFIG_MX_CYCLIC
3318 Add the "mdc" and "mwc" memory commands. These are cyclic
3319 "md/mw" commands.
3320 Examples:
3322 => mdc.b 10 4 500
3323 This command will print 4 bytes (10,11,12,13) each 500 ms.
3325 => mwc.l 100 12345678 10
3326 This command will write 12345678 to address 100 all 10 ms.
3328 This only takes effect if the memory commands are activated
3329 globally (CONFIG_CMD_MEM).
3331 - CONFIG_SKIP_LOWLEVEL_INIT
3332 [ARM, NDS32, MIPS only] If this variable is defined, then certain
3333 low level initializations (like setting up the memory
3334 controller) are omitted and/or U-Boot does not
3335 relocate itself into RAM.
3337 Normally this variable MUST NOT be defined. The only
3338 exception is when U-Boot is loaded (to RAM) by some
3339 other boot loader or by a debugger which performs
3340 these initializations itself.
3342 - CONFIG_SPL_BUILD
3343 Modifies the behaviour of start.S when compiling a loader
3344 that is executed before the actual U-Boot. E.g. when
3345 compiling a NAND SPL.
3347 - CONFIG_SYS_NAND_HW_ECC_OOBFIRST
3348 define this, if you want to read first the oob data
3349 and then the data. This is used for example on
3350 davinci plattforms.
3352 - CONFIG_USE_ARCH_MEMCPY
3353 CONFIG_USE_ARCH_MEMSET
3354 If these options are used a optimized version of memcpy/memset will
3355 be used if available. These functions may be faster under some
3356 conditions but may increase the binary size.
3358 Freescale QE/FMAN Firmware Support:
3359 -----------------------------------
3361 The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the
3362 loading of "firmware", which is encoded in the QE firmware binary format.
3363 This firmware often needs to be loaded during U-Boot booting, so macros
3364 are used to identify the storage device (NOR flash, SPI, etc) and the address
3365 within that device.
3367 - CONFIG_SYS_QE_FMAN_FW_ADDR
3368 The address in the storage device where the firmware is located. The
3369 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro
3370 is also specified.
3372 - CONFIG_SYS_QE_FMAN_FW_LENGTH
3373 The maximum possible size of the firmware. The firmware binary format
3374 has a field that specifies the actual size of the firmware, but it
3375 might not be possible to read any part of the firmware unless some
3376 local storage is allocated to hold the entire firmware first.
3378 - CONFIG_SYS_QE_FMAN_FW_IN_NOR
3379 Specifies that QE/FMAN firmware is located in NOR flash, mapped as
3380 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the
3381 virtual address in NOR flash.
3383 - CONFIG_SYS_QE_FMAN_FW_IN_NAND
3384 Specifies that QE/FMAN firmware is located in NAND flash.
3385 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash.
3387 - CONFIG_SYS_QE_FMAN_FW_IN_MMC
3388 Specifies that QE/FMAN firmware is located on the primary SD/MMC
3389 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
3391 - CONFIG_SYS_QE_FMAN_FW_IN_SPIFLASH
3392 Specifies that QE/FMAN firmware is located on the primary SPI
3393 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
3396 Building the Software:
3397 ======================
3399 Building U-Boot has been tested in several native build environments
3400 and in many different cross environments. Of course we cannot support
3401 all possibly existing versions of cross development tools in all
3402 (potentially obsolete) versions. In case of tool chain problems we
3403 recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK)
3404 which is extensively used to build and test U-Boot.
3406 If you are not using a native environment, it is assumed that you
3407 have GNU cross compiling tools available in your path. In this case,
3408 you must set the environment variable CROSS_COMPILE in your shell.
3409 Note that no changes to the Makefile or any other source files are
3410 necessary. For example using the ELDK on a 4xx CPU, please enter:
3412 $ CROSS_COMPILE=ppc_4xx-
3413 $ export CROSS_COMPILE
3415 Note: If you wish to generate Windows versions of the utilities in
3416 the tools directory you can use the MinGW toolchain
3417 (http://www.mingw.org). Set your HOST tools to the MinGW
3418 toolchain and execute 'make tools'. For example:
3420 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools
3422 Binaries such as tools/mkimage.exe will be created which can
3423 be executed on computers running Windows.
3425 U-Boot is intended to be simple to build. After installing the
3426 sources you must configure U-Boot for one specific board type. This
3427 is done by typing:
3429 make NAME_config
3431 where "NAME_config" is the name of one of the existing configu-
3432 rations; see the main Makefile for supported names.
3434 Note: for some board special configuration names may exist; check if
3435 additional information is available from the board vendor; for
3436 instance, the TQM823L systems are available without (standard)
3437 or with LCD support. You can select such additional "features"
3438 when choosing the configuration, i. e.
3440 make TQM823L_config
3441 - will configure for a plain TQM823L, i. e. no LCD support
3443 make TQM823L_LCD_config
3444 - will configure for a TQM823L with U-Boot console on LCD
3446 etc.
3449 Finally, type "make all", and you should get some working U-Boot
3450 images ready for download to / installation on your system:
3452 - "u-boot.bin" is a raw binary image
3453 - "u-boot" is an image in ELF binary format
3454 - "u-boot.srec" is in Motorola S-Record format
3456 By default the build is performed locally and the objects are saved
3457 in the source directory. One of the two methods can be used to change
3458 this behavior and build U-Boot to some external directory:
3460 1. Add O= to the make command line invocations:
3462 make O=/tmp/build distclean
3463 make O=/tmp/build NAME_config
3464 make O=/tmp/build all
3466 2. Set environment variable BUILD_DIR to point to the desired location:
3468 export BUILD_DIR=/tmp/build
3469 make distclean
3470 make NAME_config
3471 make all
3473 Note that the command line "O=" setting overrides the BUILD_DIR environment
3474 variable.
3477 Please be aware that the Makefiles assume you are using GNU make, so
3478 for instance on NetBSD you might need to use "gmake" instead of
3479 native "make".
3482 If the system board that you have is not listed, then you will need
3483 to port U-Boot to your hardware platform. To do this, follow these
3484 steps:
3486 1. Add a new configuration option for your board to the toplevel
3487 "Makefile" and to the "MAKEALL" script, using the existing
3488 entries as examples. Note that here and at many other places
3489 boards and other names are listed in alphabetical sort order. Please
3490 keep this order.
3491 2. Create a new directory to hold your board specific code. Add any
3492 files you need. In your board directory, you will need at least
3493 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
3494 3. Create a new configuration file "include/configs/<board>.h" for
3495 your board
3496 3. If you're porting U-Boot to a new CPU, then also create a new
3497 directory to hold your CPU specific code. Add any files you need.
3498 4. Run "make <board>_config" with your new name.
3499 5. Type "make", and you should get a working "u-boot.srec" file
3500 to be installed on your target system.
3501 6. Debug and solve any problems that might arise.
3502 [Of course, this last step is much harder than it sounds.]
3505 Testing of U-Boot Modifications, Ports to New Hardware, etc.:
3506 ==============================================================
3508 If you have modified U-Boot sources (for instance added a new board
3509 or support for new devices, a new CPU, etc.) you are expected to
3510 provide feedback to the other developers. The feedback normally takes
3511 the form of a "patch", i. e. a context diff against a certain (latest
3512 official or latest in the git repository) version of U-Boot sources.
3514 But before you submit such a patch, please verify that your modifi-
3515 cation did not break existing code. At least make sure that *ALL* of
3516 the supported boards compile WITHOUT ANY compiler warnings. To do so,
3517 just run the "MAKEALL" script, which will configure and build U-Boot
3518 for ALL supported system. Be warned, this will take a while. You can
3519 select which (cross) compiler to use by passing a `CROSS_COMPILE'
3520 environment variable to the script, i. e. to use the ELDK cross tools
3521 you can type
3523 CROSS_COMPILE=ppc_8xx- MAKEALL
3525 or to build on a native PowerPC system you can type
3527 CROSS_COMPILE=' ' MAKEALL
3529 When using the MAKEALL script, the default behaviour is to build
3530 U-Boot in the source directory. This location can be changed by
3531 setting the BUILD_DIR environment variable. Also, for each target
3532 built, the MAKEALL script saves two log files (<target>.ERR and
3533 <target>.MAKEALL) in the <source dir>/LOG directory. This default
3534 location can be changed by setting the MAKEALL_LOGDIR environment
3535 variable. For example:
3537 export BUILD_DIR=/tmp/build
3538 export MAKEALL_LOGDIR=/tmp/log
3539 CROSS_COMPILE=ppc_8xx- MAKEALL
3541 With the above settings build objects are saved in the /tmp/build,
3542 log files are saved in the /tmp/log and the source tree remains clean
3543 during the whole build process.
3546 See also "U-Boot Porting Guide" below.
3549 Monitor Commands - Overview:
3550 ============================
3552 go - start application at address 'addr'
3553 run - run commands in an environment variable
3554 bootm - boot application image from memory
3555 bootp - boot image via network using BootP/TFTP protocol
3556 tftpboot- boot image via network using TFTP protocol
3557 and env variables "ipaddr" and "serverip"
3558 (and eventually "gatewayip")
3559 tftpput - upload a file via network using TFTP protocol
3560 rarpboot- boot image via network using RARP/TFTP protocol
3561 diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
3562 loads - load S-Record file over serial line
3563 loadb - load binary file over serial line (kermit mode)
3564 md - memory display
3565 mm - memory modify (auto-incrementing)
3566 nm - memory modify (constant address)
3567 mw - memory write (fill)
3568 cp - memory copy
3569 cmp - memory compare
3570 crc32 - checksum calculation
3571 i2c - I2C sub-system
3572 sspi - SPI utility commands
3573 base - print or set address offset
3574 printenv- print environment variables
3575 setenv - set environment variables
3576 saveenv - save environment variables to persistent storage
3577 protect - enable or disable FLASH write protection
3578 erase - erase FLASH memory
3579 flinfo - print FLASH memory information
3580 bdinfo - print Board Info structure
3581 iminfo - print header information for application image
3582 coninfo - print console devices and informations
3583 ide - IDE sub-system
3584 loop - infinite loop on address range
3585 loopw - infinite write loop on address range
3586 mtest - simple RAM test
3587 icache - enable or disable instruction cache
3588 dcache - enable or disable data cache
3589 reset - Perform RESET of the CPU
3590 echo - echo args to console
3591 version - print monitor version
3592 help - print online help
3593 ? - alias for 'help'
3596 Monitor Commands - Detailed Description:
3597 ========================================
3599 TODO.
3601 For now: just type "help <command>".
3604 Environment Variables:
3605 ======================
3607 U-Boot supports user configuration using Environment Variables which
3608 can be made persistent by saving to Flash memory.
3610 Environment Variables are set using "setenv", printed using
3611 "printenv", and saved to Flash using "saveenv". Using "setenv"
3612 without a value can be used to delete a variable from the
3613 environment. As long as you don't save the environment you are
3614 working with an in-memory copy. In case the Flash area containing the
3615 environment is erased by accident, a default environment is provided.
3617 Some configuration options can be set using Environment Variables.
3619 List of environment variables (most likely not complete):
3621 baudrate - see CONFIG_BAUDRATE
3623 bootdelay - see CONFIG_BOOTDELAY
3625 bootcmd - see CONFIG_BOOTCOMMAND
3627 bootargs - Boot arguments when booting an RTOS image
3629 bootfile - Name of the image to load with TFTP
3631 bootm_low - Memory range available for image processing in the bootm
3632 command can be restricted. This variable is given as
3633 a hexadecimal number and defines lowest address allowed
3634 for use by the bootm command. See also "bootm_size"
3635 environment variable. Address defined by "bootm_low" is
3636 also the base of the initial memory mapping for the Linux
3637 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and
3638 bootm_mapsize.
3640 bootm_mapsize - Size of the initial memory mapping for the Linux kernel.
3641 This variable is given as a hexadecimal number and it
3642 defines the size of the memory region starting at base
3643 address bootm_low that is accessible by the Linux kernel
3644 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used
3645 as the default value if it is defined, and bootm_size is
3646 used otherwise.
3648 bootm_size - Memory range available for image processing in the bootm
3649 command can be restricted. This variable is given as
3650 a hexadecimal number and defines the size of the region
3651 allowed for use by the bootm command. See also "bootm_low"
3652 environment variable.
3654 updatefile - Location of the software update file on a TFTP server, used
3655 by the automatic software update feature. Please refer to
3656 documentation in doc/README.update for more details.
3658 autoload - if set to "no" (any string beginning with 'n'),
3659 "bootp" will just load perform a lookup of the
3660 configuration from the BOOTP server, but not try to
3661 load any image using TFTP
3663 autostart - if set to "yes", an image loaded using the "bootp",
3664 "rarpboot", "tftpboot" or "diskboot" commands will
3665 be automatically started (by internally calling
3666 "bootm")
3668 If set to "no", a standalone image passed to the
3669 "bootm" command will be copied to the load address
3670 (and eventually uncompressed), but NOT be started.
3671 This can be used to load and uncompress arbitrary
3672 data.
3674 fdt_high - if set this restricts the maximum address that the
3675 flattened device tree will be copied into upon boot.
3676 For example, if you have a system with 1 GB memory
3677 at physical address 0x10000000, while Linux kernel
3678 only recognizes the first 704 MB as low memory, you
3679 may need to set fdt_high as 0x3C000000 to have the
3680 device tree blob be copied to the maximum address
3681 of the 704 MB low memory, so that Linux kernel can
3682 access it during the boot procedure.
3684 If this is set to the special value 0xFFFFFFFF then
3685 the fdt will not be copied at all on boot. For this
3686 to work it must reside in writable memory, have
3687 sufficient padding on the end of it for u-boot to
3688 add the information it needs into it, and the memory
3689 must be accessible by the kernel.
3691 fdtcontroladdr- if set this is the address of the control flattened
3692 device tree used by U-Boot when CONFIG_OF_CONTROL is
3693 defined.
3695 i2cfast - (PPC405GP|PPC405EP only)
3696 if set to 'y' configures Linux I2C driver for fast
3697 mode (400kHZ). This environment variable is used in
3698 initialization code. So, for changes to be effective
3699 it must be saved and board must be reset.
3701 initrd_high - restrict positioning of initrd images:
3702 If this variable is not set, initrd images will be
3703 copied to the highest possible address in RAM; this
3704 is usually what you want since it allows for
3705 maximum initrd size. If for some reason you want to
3706 make sure that the initrd image is loaded below the
3707 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment
3708 variable to a value of "no" or "off" or "0".
3709 Alternatively, you can set it to a maximum upper
3710 address to use (U-Boot will still check that it
3711 does not overwrite the U-Boot stack and data).
3713 For instance, when you have a system with 16 MB
3714 RAM, and want to reserve 4 MB from use by Linux,
3715 you can do this by adding "mem=12M" to the value of
3716 the "bootargs" variable. However, now you must make
3717 sure that the initrd image is placed in the first
3718 12 MB as well - this can be done with
3720 setenv initrd_high 00c00000
3722 If you set initrd_high to 0xFFFFFFFF, this is an
3723 indication to U-Boot that all addresses are legal
3724 for the Linux kernel, including addresses in flash
3725 memory. In this case U-Boot will NOT COPY the
3726 ramdisk at all. This may be useful to reduce the
3727 boot time on your system, but requires that this
3728 feature is supported by your Linux kernel.
3730 ipaddr - IP address; needed for tftpboot command
3732 loadaddr - Default load address for commands like "bootp",
3733 "rarpboot", "tftpboot", "loadb" or "diskboot"
3735 loads_echo - see CONFIG_LOADS_ECHO
3737 serverip - TFTP server IP address; needed for tftpboot command
3739 bootretry - see CONFIG_BOOT_RETRY_TIME
3741 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
3743 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
3745 ethprime - controls which interface is used first.
3747 ethact - controls which interface is currently active.
3748 For example you can do the following
3750 => setenv ethact FEC
3751 => ping 192.168.0.1 # traffic sent on FEC
3752 => setenv ethact SCC
3753 => ping 10.0.0.1 # traffic sent on SCC
3755 ethrotate - When set to "no" U-Boot does not go through all
3756 available network interfaces.
3757 It just stays at the currently selected interface.
3759 netretry - When set to "no" each network operation will
3760 either succeed or fail without retrying.
3761 When set to "once" the network operation will
3762 fail when all the available network interfaces
3763 are tried once without success.
3764 Useful on scripts which control the retry operation
3765 themselves.
3767 npe_ucode - set load address for the NPE microcode
3769 tftpsrcport - If this is set, the value is used for TFTP's
3770 UDP source port.
3772 tftpdstport - If this is set, the value is used for TFTP's UDP
3773 destination port instead of the Well Know Port 69.
3775 tftpblocksize - Block size to use for TFTP transfers; if not set,
3776 we use the TFTP server's default block size
3778 tftptimeout - Retransmission timeout for TFTP packets (in milli-
3779 seconds, minimum value is 1000 = 1 second). Defines
3780 when a packet is considered to be lost so it has to
3781 be retransmitted. The default is 5000 = 5 seconds.
3782 Lowering this value may make downloads succeed
3783 faster in networks with high packet loss rates or
3784 with unreliable TFTP servers.
3786 vlan - When set to a value < 4095 the traffic over
3787 Ethernet is encapsulated/received over 802.1q
3788 VLAN tagged frames.
3790 The following image location variables contain the location of images
3791 used in booting. The "Image" column gives the role of the image and is
3792 not an environment variable name. The other columns are environment
3793 variable names. "File Name" gives the name of the file on a TFTP
3794 server, "RAM Address" gives the location in RAM the image will be
3795 loaded to, and "Flash Location" gives the image's address in NOR
3796 flash or offset in NAND flash.
3798 *Note* - these variables don't have to be defined for all boards, some
3799 boards currenlty use other variables for these purposes, and some
3800 boards use these variables for other purposes.
3802 Image File Name RAM Address Flash Location
3803 ----- --------- ----------- --------------
3804 u-boot u-boot u-boot_addr_r u-boot_addr
3805 Linux kernel bootfile kernel_addr_r kernel_addr
3806 device tree blob fdtfile fdt_addr_r fdt_addr
3807 ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr
3809 The following environment variables may be used and automatically
3810 updated by the network boot commands ("bootp" and "rarpboot"),
3811 depending the information provided by your boot server:
3813 bootfile - see above
3814 dnsip - IP address of your Domain Name Server
3815 dnsip2 - IP address of your secondary Domain Name Server
3816 gatewayip - IP address of the Gateway (Router) to use
3817 hostname - Target hostname
3818 ipaddr - see above
3819 netmask - Subnet Mask
3820 rootpath - Pathname of the root filesystem on the NFS server
3821 serverip - see above
3824 There are two special Environment Variables:
3826 serial# - contains hardware identification information such
3827 as type string and/or serial number
3828 ethaddr - Ethernet address
3830 These variables can be set only once (usually during manufacturing of
3831 the board). U-Boot refuses to delete or overwrite these variables
3832 once they have been set once.
3835 Further special Environment Variables:
3837 ver - Contains the U-Boot version string as printed
3838 with the "version" command. This variable is
3839 readonly (see CONFIG_VERSION_VARIABLE).
3842 Please note that changes to some configuration parameters may take
3843 only effect after the next boot (yes, that's just like Windoze :-).
3846 Command Line Parsing:
3847 =====================
3849 There are two different command line parsers available with U-Boot:
3850 the old "simple" one, and the much more powerful "hush" shell:
3852 Old, simple command line parser:
3853 --------------------------------
3855 - supports environment variables (through setenv / saveenv commands)
3856 - several commands on one line, separated by ';'
3857 - variable substitution using "... ${name} ..." syntax
3858 - special characters ('$', ';') can be escaped by prefixing with '\',
3859 for example:
3860 setenv bootcmd bootm \${address}
3861 - You can also escape text by enclosing in single apostrophes, for example:
3862 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
3864 Hush shell:
3865 -----------
3867 - similar to Bourne shell, with control structures like
3868 if...then...else...fi, for...do...done; while...do...done,
3869 until...do...done, ...
3870 - supports environment ("global") variables (through setenv / saveenv
3871 commands) and local shell variables (through standard shell syntax
3872 "name=value"); only environment variables can be used with "run"
3873 command
3875 General rules:
3876 --------------
3878 (1) If a command line (or an environment variable executed by a "run"
3879 command) contains several commands separated by semicolon, and
3880 one of these commands fails, then the remaining commands will be
3881 executed anyway.
3883 (2) If you execute several variables with one call to run (i. e.
3884 calling run with a list of variables as arguments), any failing
3885 command will cause "run" to terminate, i. e. the remaining
3886 variables are not executed.
3888 Note for Redundant Ethernet Interfaces:
3889 =======================================
3891 Some boards come with redundant Ethernet interfaces; U-Boot supports
3892 such configurations and is capable of automatic selection of a
3893 "working" interface when needed. MAC assignment works as follows:
3895 Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
3896 MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
3897 "eth1addr" (=>eth1), "eth2addr", ...
3899 If the network interface stores some valid MAC address (for instance
3900 in SROM), this is used as default address if there is NO correspon-
3901 ding setting in the environment; if the corresponding environment
3902 variable is set, this overrides the settings in the card; that means:
3904 o If the SROM has a valid MAC address, and there is no address in the
3905 environment, the SROM's address is used.
3907 o If there is no valid address in the SROM, and a definition in the
3908 environment exists, then the value from the environment variable is
3909 used.
3911 o If both the SROM and the environment contain a MAC address, and
3912 both addresses are the same, this MAC address is used.
3914 o If both the SROM and the environment contain a MAC address, and the
3915 addresses differ, the value from the environment is used and a
3916 warning is printed.
3918 o If neither SROM nor the environment contain a MAC address, an error
3919 is raised.
3921 If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses
3922 will be programmed into hardware as part of the initialization process. This
3923 may be skipped by setting the appropriate 'ethmacskip' environment variable.
3924 The naming convention is as follows:
3925 "ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc.
3927 Image Formats:
3928 ==============
3930 U-Boot is capable of booting (and performing other auxiliary operations on)
3931 images in two formats:
3933 New uImage format (FIT)
3934 -----------------------
3936 Flexible and powerful format based on Flattened Image Tree -- FIT (similar
3937 to Flattened Device Tree). It allows the use of images with multiple
3938 components (several kernels, ramdisks, etc.), with contents protected by
3939 SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
3942 Old uImage format
3943 -----------------
3945 Old image format is based on binary files which can be basically anything,
3946 preceded by a special header; see the definitions in include/image.h for
3947 details; basically, the header defines the following image properties:
3949 * Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
3950 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
3951 LynxOS, pSOS, QNX, RTEMS, INTEGRITY;
3952 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS,
3953 INTEGRITY).
3954 * Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86,
3955 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
3956 Currently supported: ARM, AVR32, Intel x86, MIPS, NDS32, Nios II, PowerPC).
3957 * Compression Type (uncompressed, gzip, bzip2)
3958 * Load Address
3959 * Entry Point
3960 * Image Name
3961 * Image Timestamp
3963 The header is marked by a special Magic Number, and both the header
3964 and the data portions of the image are secured against corruption by
3965 CRC32 checksums.
3968 Linux Support:
3969 ==============
3971 Although U-Boot should support any OS or standalone application
3972 easily, the main focus has always been on Linux during the design of
3973 U-Boot.
3975 U-Boot includes many features that so far have been part of some
3976 special "boot loader" code within the Linux kernel. Also, any
3977 "initrd" images to be used are no longer part of one big Linux image;
3978 instead, kernel and "initrd" are separate images. This implementation
3979 serves several purposes:
3981 - the same features can be used for other OS or standalone
3982 applications (for instance: using compressed images to reduce the
3983 Flash memory footprint)
3985 - it becomes much easier to port new Linux kernel versions because
3986 lots of low-level, hardware dependent stuff are done by U-Boot
3988 - the same Linux kernel image can now be used with different "initrd"
3989 images; of course this also means that different kernel images can
3990 be run with the same "initrd". This makes testing easier (you don't
3991 have to build a new "zImage.initrd" Linux image when you just
3992 change a file in your "initrd"). Also, a field-upgrade of the
3993 software is easier now.
3996 Linux HOWTO:
3997 ============
3999 Porting Linux to U-Boot based systems:
4000 ---------------------------------------
4002 U-Boot cannot save you from doing all the necessary modifications to
4003 configure the Linux device drivers for use with your target hardware
4004 (no, we don't intend to provide a full virtual machine interface to
4005 Linux :-).
4007 But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot).
4009 Just make sure your machine specific header file (for instance
4010 include/asm-ppc/tqm8xx.h) includes the same definition of the Board
4011 Information structure as we define in include/asm-<arch>/u-boot.h,
4012 and make sure that your definition of IMAP_ADDR uses the same value
4013 as your U-Boot configuration in CONFIG_SYS_IMMR.
4016 Configuring the Linux kernel:
4017 -----------------------------
4019 No specific requirements for U-Boot. Make sure you have some root
4020 device (initial ramdisk, NFS) for your target system.
4023 Building a Linux Image:
4024 -----------------------
4026 With U-Boot, "normal" build targets like "zImage" or "bzImage" are
4027 not used. If you use recent kernel source, a new build target
4028 "uImage" will exist which automatically builds an image usable by
4029 U-Boot. Most older kernels also have support for a "pImage" target,
4030 which was introduced for our predecessor project PPCBoot and uses a
4031 100% compatible format.
4033 Example:
4035 make TQM850L_config
4036 make oldconfig
4037 make dep
4038 make uImage
4040 The "uImage" build target uses a special tool (in 'tools/mkimage') to
4041 encapsulate a compressed Linux kernel image with header information,
4042 CRC32 checksum etc. for use with U-Boot. This is what we are doing:
4044 * build a standard "vmlinux" kernel image (in ELF binary format):
4046 * convert the kernel into a raw binary image:
4048 ${CROSS_COMPILE}-objcopy -O binary \
4049 -R .note -R .comment \
4050 -S vmlinux linux.bin
4052 * compress the binary image:
4054 gzip -9 linux.bin
4056 * package compressed binary image for U-Boot:
4058 mkimage -A ppc -O linux -T kernel -C gzip \
4059 -a 0 -e 0 -n "Linux Kernel Image" \
4060 -d linux.bin.gz uImage
4063 The "mkimage" tool can also be used to create ramdisk images for use
4064 with U-Boot, either separated from the Linux kernel image, or
4065 combined into one file. "mkimage" encapsulates the images with a 64
4066 byte header containing information about target architecture,
4067 operating system, image type, compression method, entry points, time
4068 stamp, CRC32 checksums, etc.
4070 "mkimage" can be called in two ways: to verify existing images and
4071 print the header information, or to build new images.
4073 In the first form (with "-l" option) mkimage lists the information
4074 contained in the header of an existing U-Boot image; this includes
4075 checksum verification:
4077 tools/mkimage -l image
4078 -l ==> list image header information
4080 The second form (with "-d" option) is used to build a U-Boot image
4081 from a "data file" which is used as image payload:
4083 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
4084 -n name -d data_file image
4085 -A ==> set architecture to 'arch'
4086 -O ==> set operating system to 'os'
4087 -T ==> set image type to 'type'
4088 -C ==> set compression type 'comp'
4089 -a ==> set load address to 'addr' (hex)
4090 -e ==> set entry point to 'ep' (hex)
4091 -n ==> set image name to 'name'
4092 -d ==> use image data from 'datafile'
4094 Right now, all Linux kernels for PowerPC systems use the same load
4095 address (0x00000000), but the entry point address depends on the
4096 kernel version:
4098 - 2.2.x kernels have the entry point at 0x0000000C,
4099 - 2.3.x and later kernels have the entry point at 0x00000000.
4101 So a typical call to build a U-Boot image would read:
4103 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
4104 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
4105 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \
4106 > examples/uImage.TQM850L
4107 Image Name: 2.4.4 kernel for TQM850L
4108 Created: Wed Jul 19 02:34:59 2000
4109 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4110 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
4111 Load Address: 0x00000000
4112 Entry Point: 0x00000000
4114 To verify the contents of the image (or check for corruption):
4116 -> tools/mkimage -l examples/uImage.TQM850L
4117 Image Name: 2.4.4 kernel for TQM850L
4118 Created: Wed Jul 19 02:34:59 2000
4119 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4120 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
4121 Load Address: 0x00000000
4122 Entry Point: 0x00000000
4124 NOTE: for embedded systems where boot time is critical you can trade
4125 speed for memory and install an UNCOMPRESSED image instead: this
4126 needs more space in Flash, but boots much faster since it does not
4127 need to be uncompressed:
4129 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz
4130 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
4131 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
4132 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \
4133 > examples/uImage.TQM850L-uncompressed
4134 Image Name: 2.4.4 kernel for TQM850L
4135 Created: Wed Jul 19 02:34:59 2000
4136 Image Type: PowerPC Linux Kernel Image (uncompressed)
4137 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
4138 Load Address: 0x00000000
4139 Entry Point: 0x00000000
4142 Similar you can build U-Boot images from a 'ramdisk.image.gz' file
4143 when your kernel is intended to use an initial ramdisk:
4145 -> tools/mkimage -n 'Simple Ramdisk Image' \
4146 > -A ppc -O linux -T ramdisk -C gzip \
4147 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
4148 Image Name: Simple Ramdisk Image
4149 Created: Wed Jan 12 14:01:50 2000
4150 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
4151 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
4152 Load Address: 0x00000000
4153 Entry Point: 0x00000000
4156 Installing a Linux Image:
4157 -------------------------
4159 To downloading a U-Boot image over the serial (console) interface,
4160 you must convert the image to S-Record format:
4162 objcopy -I binary -O srec examples/image examples/image.srec
4164 The 'objcopy' does not understand the information in the U-Boot
4165 image header, so the resulting S-Record file will be relative to
4166 address 0x00000000. To load it to a given address, you need to
4167 specify the target address as 'offset' parameter with the 'loads'
4168 command.
4170 Example: install the image to address 0x40100000 (which on the
4171 TQM8xxL is in the first Flash bank):
4173 => erase 40100000 401FFFFF
4175 .......... done
4176 Erased 8 sectors
4178 => loads 40100000
4179 ## Ready for S-Record download ...
4180 ~>examples/image.srec
4181 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
4182 ...
4183 15989 15990 15991 15992
4184 [file transfer complete]
4185 [connected]
4186 ## Start Addr = 0x00000000
4189 You can check the success of the download using the 'iminfo' command;
4190 this includes a checksum verification so you can be sure no data
4191 corruption happened:
4193 => imi 40100000
4195 ## Checking Image at 40100000 ...
4196 Image Name: 2.2.13 for initrd on TQM850L
4197 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4198 Data Size: 335725 Bytes = 327 kB = 0 MB
4199 Load Address: 00000000
4200 Entry Point: 0000000c
4201 Verifying Checksum ... OK
4204 Boot Linux:
4205 -----------
4207 The "bootm" command is used to boot an application that is stored in
4208 memory (RAM or Flash). In case of a Linux kernel image, the contents
4209 of the "bootargs" environment variable is passed to the kernel as
4210 parameters. You can check and modify this variable using the
4211 "printenv" and "setenv" commands:
4214 => printenv bootargs
4215 bootargs=root=/dev/ram
4217 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
4219 => printenv bootargs
4220 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
4222 => bootm 40020000
4223 ## Booting Linux kernel at 40020000 ...
4224 Image Name: 2.2.13 for NFS on TQM850L
4225 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4226 Data Size: 381681 Bytes = 372 kB = 0 MB
4227 Load Address: 00000000
4228 Entry Point: 0000000c
4229 Verifying Checksum ... OK
4230 Uncompressing Kernel Image ... OK
4231 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
4232 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
4233 time_init: decrementer frequency = 187500000/60
4234 Calibrating delay loop... 49.77 BogoMIPS
4235 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
4236 ...
4238 If you want to boot a Linux kernel with initial RAM disk, you pass
4239 the memory addresses of both the kernel and the initrd image (PPBCOOT
4240 format!) to the "bootm" command:
4242 => imi 40100000 40200000
4244 ## Checking Image at 40100000 ...
4245 Image Name: 2.2.13 for initrd on TQM850L
4246 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4247 Data Size: 335725 Bytes = 327 kB = 0 MB
4248 Load Address: 00000000
4249 Entry Point: 0000000c
4250 Verifying Checksum ... OK
4252 ## Checking Image at 40200000 ...
4253 Image Name: Simple Ramdisk Image
4254 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
4255 Data Size: 566530 Bytes = 553 kB = 0 MB
4256 Load Address: 00000000
4257 Entry Point: 00000000
4258 Verifying Checksum ... OK
4260 => bootm 40100000 40200000
4261 ## Booting Linux kernel at 40100000 ...
4262 Image Name: 2.2.13 for initrd on TQM850L
4263 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4264 Data Size: 335725 Bytes = 327 kB = 0 MB
4265 Load Address: 00000000
4266 Entry Point: 0000000c
4267 Verifying Checksum ... OK
4268 Uncompressing Kernel Image ... OK
4269 ## Loading RAMDisk Image at 40200000 ...
4270 Image Name: Simple Ramdisk Image
4271 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
4272 Data Size: 566530 Bytes = 553 kB = 0 MB
4273 Load Address: 00000000
4274 Entry Point: 00000000
4275 Verifying Checksum ... OK
4276 Loading Ramdisk ... OK
4277 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
4278 Boot arguments: root=/dev/ram
4279 time_init: decrementer frequency = 187500000/60
4280 Calibrating delay loop... 49.77 BogoMIPS
4281 ...
4282 RAMDISK: Compressed image found at block 0
4283 VFS: Mounted root (ext2 filesystem).
4285 bash#
4287 Boot Linux and pass a flat device tree:
4288 -----------
4290 First, U-Boot must be compiled with the appropriate defines. See the section
4291 titled "Linux Kernel Interface" above for a more in depth explanation. The
4292 following is an example of how to start a kernel and pass an updated
4293 flat device tree:
4295 => print oftaddr
4296 oftaddr=0x300000
4297 => print oft
4298 oft=oftrees/mpc8540ads.dtb
4299 => tftp $oftaddr $oft
4300 Speed: 1000, full duplex
4301 Using TSEC0 device
4302 TFTP from server 192.168.1.1; our IP address is 192.168.1.101
4303 Filename 'oftrees/mpc8540ads.dtb'.
4304 Load address: 0x300000
4305 Loading: #
4306 done
4307 Bytes transferred = 4106 (100a hex)
4308 => tftp $loadaddr $bootfile
4309 Speed: 1000, full duplex
4310 Using TSEC0 device
4311 TFTP from server 192.168.1.1; our IP address is 192.168.1.2
4312 Filename 'uImage'.
4313 Load address: 0x200000
4314 Loading:############
4315 done
4316 Bytes transferred = 1029407 (fb51f hex)
4317 => print loadaddr
4318 loadaddr=200000
4319 => print oftaddr
4320 oftaddr=0x300000
4321 => bootm $loadaddr - $oftaddr
4322 ## Booting image at 00200000 ...
4323 Image Name: Linux-2.6.17-dirty
4324 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4325 Data Size: 1029343 Bytes = 1005.2 kB
4326 Load Address: 00000000
4327 Entry Point: 00000000
4328 Verifying Checksum ... OK
4329 Uncompressing Kernel Image ... OK
4330 Booting using flat device tree at 0x300000
4331 Using MPC85xx ADS machine description
4332 Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb
4333 [snip]
4336 More About U-Boot Image Types:
4337 ------------------------------
4339 U-Boot supports the following image types:
4341 "Standalone Programs" are directly runnable in the environment
4342 provided by U-Boot; it is expected that (if they behave
4343 well) you can continue to work in U-Boot after return from
4344 the Standalone Program.
4345 "OS Kernel Images" are usually images of some Embedded OS which
4346 will take over control completely. Usually these programs
4347 will install their own set of exception handlers, device
4348 drivers, set up the MMU, etc. - this means, that you cannot
4349 expect to re-enter U-Boot except by resetting the CPU.
4350 "RAMDisk Images" are more or less just data blocks, and their
4351 parameters (address, size) are passed to an OS kernel that is
4352 being started.
4353 "Multi-File Images" contain several images, typically an OS
4354 (Linux) kernel image and one or more data images like
4355 RAMDisks. This construct is useful for instance when you want
4356 to boot over the network using BOOTP etc., where the boot
4357 server provides just a single image file, but you want to get
4358 for instance an OS kernel and a RAMDisk image.
4360 "Multi-File Images" start with a list of image sizes, each
4361 image size (in bytes) specified by an "uint32_t" in network
4362 byte order. This list is terminated by an "(uint32_t)0".
4363 Immediately after the terminating 0 follow the images, one by
4364 one, all aligned on "uint32_t" boundaries (size rounded up to
4365 a multiple of 4 bytes).
4367 "Firmware Images" are binary images containing firmware (like
4368 U-Boot or FPGA images) which usually will be programmed to
4369 flash memory.
4371 "Script files" are command sequences that will be executed by
4372 U-Boot's command interpreter; this feature is especially
4373 useful when you configure U-Boot to use a real shell (hush)
4374 as command interpreter.
4377 Standalone HOWTO:
4378 =================
4380 One of the features of U-Boot is that you can dynamically load and
4381 run "standalone" applications, which can use some resources of
4382 U-Boot like console I/O functions or interrupt services.
4384 Two simple examples are included with the sources:
4386 "Hello World" Demo:
4387 -------------------
4389 'examples/hello_world.c' contains a small "Hello World" Demo
4390 application; it is automatically compiled when you build U-Boot.
4391 It's configured to run at address 0x00040004, so you can play with it
4392 like that:
4394 => loads
4395 ## Ready for S-Record download ...
4396 ~>examples/hello_world.srec
4397 1 2 3 4 5 6 7 8 9 10 11 ...
4398 [file transfer complete]
4399 [connected]
4400 ## Start Addr = 0x00040004
4402 => go 40004 Hello World! This is a test.
4403 ## Starting application at 0x00040004 ...
4404 Hello World
4405 argc = 7
4406 argv[0] = "40004"
4407 argv[1] = "Hello"
4408 argv[2] = "World!"
4409 argv[3] = "This"
4410 argv[4] = "is"
4411 argv[5] = "a"
4412 argv[6] = "test."
4413 argv[7] = "<NULL>"
4414 Hit any key to exit ...
4416 ## Application terminated, rc = 0x0
4418 Another example, which demonstrates how to register a CPM interrupt
4419 handler with the U-Boot code, can be found in 'examples/timer.c'.
4420 Here, a CPM timer is set up to generate an interrupt every second.
4421 The interrupt service routine is trivial, just printing a '.'
4422 character, but this is just a demo program. The application can be
4423 controlled by the following keys:
4425 ? - print current values og the CPM Timer registers
4426 b - enable interrupts and start timer
4427 e - stop timer and disable interrupts
4428 q - quit application
4430 => loads
4431 ## Ready for S-Record download ...
4432 ~>examples/timer.srec
4433 1 2 3 4 5 6 7 8 9 10 11 ...
4434 [file transfer complete]
4435 [connected]
4436 ## Start Addr = 0x00040004
4438 => go 40004
4439 ## Starting application at 0x00040004 ...
4440 TIMERS=0xfff00980
4441 Using timer 1
4442 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
4444 Hit 'b':
4445 [q, b, e, ?] Set interval 1000000 us
4446 Enabling timer
4447 Hit '?':
4448 [q, b, e, ?] ........
4449 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
4450 Hit '?':
4451 [q, b, e, ?] .
4452 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
4453 Hit '?':
4454 [q, b, e, ?] .
4455 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
4456 Hit '?':
4457 [q, b, e, ?] .
4458 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
4459 Hit 'e':
4460 [q, b, e, ?] ...Stopping timer
4461 Hit 'q':
4462 [q, b, e, ?] ## Application terminated, rc = 0x0
4465 Minicom warning:
4466 ================
4468 Over time, many people have reported problems when trying to use the
4469 "minicom" terminal emulation program for serial download. I (wd)
4470 consider minicom to be broken, and recommend not to use it. Under
4471 Unix, I recommend to use C-Kermit for general purpose use (and
4472 especially for kermit binary protocol download ("loadb" command), and
4473 use "cu" for S-Record download ("loads" command).
4475 Nevertheless, if you absolutely want to use it try adding this
4476 configuration to your "File transfer protocols" section:
4478 Name Program Name U/D FullScr IO-Red. Multi
4479 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
4480 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
4483 NetBSD Notes:
4484 =============
4486 Starting at version 0.9.2, U-Boot supports NetBSD both as host
4487 (build U-Boot) and target system (boots NetBSD/mpc8xx).
4489 Building requires a cross environment; it is known to work on
4490 NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
4491 need gmake since the Makefiles are not compatible with BSD make).
4492 Note that the cross-powerpc package does not install include files;
4493 attempting to build U-Boot will fail because <machine/ansi.h> is
4494 missing. This file has to be installed and patched manually:
4496 # cd /usr/pkg/cross/powerpc-netbsd/include
4497 # mkdir powerpc
4498 # ln -s powerpc machine
4499 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
4500 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
4502 Native builds *don't* work due to incompatibilities between native
4503 and U-Boot include files.
4505 Booting assumes that (the first part of) the image booted is a
4506 stage-2 loader which in turn loads and then invokes the kernel
4507 proper. Loader sources will eventually appear in the NetBSD source
4508 tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
4509 meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
4512 Implementation Internals:
4513 =========================
4515 The following is not intended to be a complete description of every
4516 implementation detail. However, it should help to understand the
4517 inner workings of U-Boot and make it easier to port it to custom
4518 hardware.
4521 Initial Stack, Global Data:
4522 ---------------------------
4524 The implementation of U-Boot is complicated by the fact that U-Boot
4525 starts running out of ROM (flash memory), usually without access to
4526 system RAM (because the memory controller is not initialized yet).
4527 This means that we don't have writable Data or BSS segments, and BSS
4528 is not initialized as zero. To be able to get a C environment working
4529 at all, we have to allocate at least a minimal stack. Implementation
4530 options for this are defined and restricted by the CPU used: Some CPU
4531 models provide on-chip memory (like the IMMR area on MPC8xx and
4532 MPC826x processors), on others (parts of) the data cache can be
4533 locked as (mis-) used as memory, etc.
4535 Chris Hallinan posted a good summary of these issues to the
4536 U-Boot mailing list:
4538 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
4539 From: "Chris Hallinan" <clh@net1plus.com>
4540 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
4541 ...
4543 Correct me if I'm wrong, folks, but the way I understand it
4544 is this: Using DCACHE as initial RAM for Stack, etc, does not
4545 require any physical RAM backing up the cache. The cleverness
4546 is that the cache is being used as a temporary supply of
4547 necessary storage before the SDRAM controller is setup. It's
4548 beyond the scope of this list to explain the details, but you
4549 can see how this works by studying the cache architecture and
4550 operation in the architecture and processor-specific manuals.
4552 OCM is On Chip Memory, which I believe the 405GP has 4K. It
4553 is another option for the system designer to use as an
4554 initial stack/RAM area prior to SDRAM being available. Either
4555 option should work for you. Using CS 4 should be fine if your
4556 board designers haven't used it for something that would
4557 cause you grief during the initial boot! It is frequently not
4558 used.
4560 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere
4561 with your processor/board/system design. The default value
4562 you will find in any recent u-boot distribution in
4563 walnut.h should work for you. I'd set it to a value larger
4564 than your SDRAM module. If you have a 64MB SDRAM module, set
4565 it above 400_0000. Just make sure your board has no resources
4566 that are supposed to respond to that address! That code in
4567 start.S has been around a while and should work as is when
4568 you get the config right.
4570 -Chris Hallinan
4571 DS4.COM, Inc.
4573 It is essential to remember this, since it has some impact on the C
4574 code for the initialization procedures:
4576 * Initialized global data (data segment) is read-only. Do not attempt
4577 to write it.
4579 * Do not use any uninitialized global data (or implicitely initialized
4580 as zero data - BSS segment) at all - this is undefined, initiali-
4581 zation is performed later (when relocating to RAM).
4583 * Stack space is very limited. Avoid big data buffers or things like
4584 that.
4586 Having only the stack as writable memory limits means we cannot use
4587 normal global data to share information beween the code. But it
4588 turned out that the implementation of U-Boot can be greatly
4589 simplified by making a global data structure (gd_t) available to all
4590 functions. We could pass a pointer to this data as argument to _all_
4591 functions, but this would bloat the code. Instead we use a feature of
4592 the GCC compiler (Global Register Variables) to share the data: we
4593 place a pointer (gd) to the global data into a register which we
4594 reserve for this purpose.
4596 When choosing a register for such a purpose we are restricted by the
4597 relevant (E)ABI specifications for the current architecture, and by
4598 GCC's implementation.
4600 For PowerPC, the following registers have specific use:
4601 R1: stack pointer
4602 R2: reserved for system use
4603 R3-R4: parameter passing and return values
4604 R5-R10: parameter passing
4605 R13: small data area pointer
4606 R30: GOT pointer
4607 R31: frame pointer
4609 (U-Boot also uses R12 as internal GOT pointer. r12
4610 is a volatile register so r12 needs to be reset when
4611 going back and forth between asm and C)
4613 ==> U-Boot will use R2 to hold a pointer to the global data
4615 Note: on PPC, we could use a static initializer (since the
4616 address of the global data structure is known at compile time),
4617 but it turned out that reserving a register results in somewhat
4618 smaller code - although the code savings are not that big (on
4619 average for all boards 752 bytes for the whole U-Boot image,
4620 624 text + 127 data).
4622 On Blackfin, the normal C ABI (except for P3) is followed as documented here:
4623 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface
4625 ==> U-Boot will use P3 to hold a pointer to the global data
4627 On ARM, the following registers are used:
4629 R0: function argument word/integer result
4630 R1-R3: function argument word
4631 R9: GOT pointer
4632 R10: stack limit (used only if stack checking if enabled)
4633 R11: argument (frame) pointer
4634 R12: temporary workspace
4635 R13: stack pointer
4636 R14: link register
4637 R15: program counter
4639 ==> U-Boot will use R8 to hold a pointer to the global data
4641 On Nios II, the ABI is documented here:
4642 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf
4644 ==> U-Boot will use gp to hold a pointer to the global data
4646 Note: on Nios II, we give "-G0" option to gcc and don't use gp
4647 to access small data sections, so gp is free.
4649 On NDS32, the following registers are used:
4651 R0-R1: argument/return
4652 R2-R5: argument
4653 R15: temporary register for assembler
4654 R16: trampoline register
4655 R28: frame pointer (FP)
4656 R29: global pointer (GP)
4657 R30: link register (LP)
4658 R31: stack pointer (SP)
4659 PC: program counter (PC)
4661 ==> U-Boot will use R10 to hold a pointer to the global data
4663 NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
4664 or current versions of GCC may "optimize" the code too much.
4666 Memory Management:
4667 ------------------
4669 U-Boot runs in system state and uses physical addresses, i.e. the
4670 MMU is not used either for address mapping nor for memory protection.
4672 The available memory is mapped to fixed addresses using the memory
4673 controller. In this process, a contiguous block is formed for each
4674 memory type (Flash, SDRAM, SRAM), even when it consists of several
4675 physical memory banks.
4677 U-Boot is installed in the first 128 kB of the first Flash bank (on
4678 TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
4679 booting and sizing and initializing DRAM, the code relocates itself
4680 to the upper end of DRAM. Immediately below the U-Boot code some
4681 memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN
4682 configuration setting]. Below that, a structure with global Board
4683 Info data is placed, followed by the stack (growing downward).
4685 Additionally, some exception handler code is copied to the low 8 kB
4686 of DRAM (0x00000000 ... 0x00001FFF).
4688 So a typical memory configuration with 16 MB of DRAM could look like
4689 this:
4691 0x0000 0000 Exception Vector code
4692 :
4693 0x0000 1FFF
4694 0x0000 2000 Free for Application Use
4695 :
4696 :
4698 :
4699 :
4700 0x00FB FF20 Monitor Stack (Growing downward)
4701 0x00FB FFAC Board Info Data and permanent copy of global data
4702 0x00FC 0000 Malloc Arena
4703 :
4704 0x00FD FFFF
4705 0x00FE 0000 RAM Copy of Monitor Code
4706 ... eventually: LCD or video framebuffer
4707 ... eventually: pRAM (Protected RAM - unchanged by reset)
4708 0x00FF FFFF [End of RAM]
4711 System Initialization:
4712 ----------------------
4714 In the reset configuration, U-Boot starts at the reset entry point
4715 (on most PowerPC systems at address 0x00000100). Because of the reset
4716 configuration for CS0# this is a mirror of the onboard Flash memory.
4717 To be able to re-map memory U-Boot then jumps to its link address.
4718 To be able to implement the initialization code in C, a (small!)
4719 initial stack is set up in the internal Dual Ported RAM (in case CPUs
4720 which provide such a feature like MPC8xx or MPC8260), or in a locked
4721 part of the data cache. After that, U-Boot initializes the CPU core,
4722 the caches and the SIU.
4724 Next, all (potentially) available memory banks are mapped using a
4725 preliminary mapping. For example, we put them on 512 MB boundaries
4726 (multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
4727 on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
4728 programmed for SDRAM access. Using the temporary configuration, a
4729 simple memory test is run that determines the size of the SDRAM
4730 banks.
4732 When there is more than one SDRAM bank, and the banks are of
4733 different size, the largest is mapped first. For equal size, the first
4734 bank (CS2#) is mapped first. The first mapping is always for address
4735 0x00000000, with any additional banks following immediately to create
4736 contiguous memory starting from 0.
4738 Then, the monitor installs itself at the upper end of the SDRAM area
4739 and allocates memory for use by malloc() and for the global Board
4740 Info data; also, the exception vector code is copied to the low RAM
4741 pages, and the final stack is set up.
4743 Only after this relocation will you have a "normal" C environment;
4744 until that you are restricted in several ways, mostly because you are
4745 running from ROM, and because the code will have to be relocated to a
4746 new address in RAM.
4749 U-Boot Porting Guide:
4750 ----------------------
4752 [Based on messages by Jerry Van Baren in the U-Boot-Users mailing
4753 list, October 2002]
4756 int main(int argc, char *argv[])
4757 {
4758 sighandler_t no_more_time;
4760 signal(SIGALRM, no_more_time);
4761 alarm(PROJECT_DEADLINE - toSec (3 * WEEK));
4763 if (available_money > available_manpower) {
4764 Pay consultant to port U-Boot;
4765 return 0;
4766 }
4768 Download latest U-Boot source;
4770 Subscribe to u-boot mailing list;
4772 if (clueless)
4773 email("Hi, I am new to U-Boot, how do I get started?");
4775 while (learning) {
4776 Read the README file in the top level directory;
4777 Read http://www.denx.de/twiki/bin/view/DULG/Manual;
4778 Read applicable doc/*.README;
4779 Read the source, Luke;
4780 /* find . -name "*.[chS]" | xargs grep -i <keyword> */
4781 }
4783 if (available_money > toLocalCurrency ($2500))
4784 Buy a BDI3000;
4785 else
4786 Add a lot of aggravation and time;
4788 if (a similar board exists) { /* hopefully... */
4789 cp -a board/<similar> board/<myboard>
4790 cp include/configs/<similar>.h include/configs/<myboard>.h
4791 } else {
4792 Create your own board support subdirectory;
4793 Create your own board include/configs/<myboard>.h file;
4794 }
4795 Edit new board/<myboard> files
4796 Edit new include/configs/<myboard>.h
4798 while (!accepted) {
4799 while (!running) {
4800 do {
4801 Add / modify source code;
4802 } until (compiles);
4803 Debug;
4804 if (clueless)
4805 email("Hi, I am having problems...");
4806 }
4807 Send patch file to the U-Boot email list;
4808 if (reasonable critiques)
4809 Incorporate improvements from email list code review;
4810 else
4811 Defend code as written;
4812 }
4814 return 0;
4815 }
4817 void no_more_time (int sig)
4818 {
4819 hire_a_guru();
4820 }
4823 Coding Standards:
4824 -----------------
4826 All contributions to U-Boot should conform to the Linux kernel
4827 coding style; see the file "Documentation/CodingStyle" and the script
4828 "scripts/Lindent" in your Linux kernel source directory.
4830 Source files originating from a different project (for example the
4831 MTD subsystem) are generally exempt from these guidelines and are not
4832 reformated to ease subsequent migration to newer versions of those
4833 sources.
4835 Please note that U-Boot is implemented in C (and to some small parts in
4836 Assembler); no C++ is used, so please do not use C++ style comments (//)
4837 in your code.
4839 Please also stick to the following formatting rules:
4840 - remove any trailing white space
4841 - use TAB characters for indentation and vertical alignment, not spaces
4842 - make sure NOT to use DOS '\r\n' line feeds
4843 - do not add more than 2 consecutive empty lines to source files
4844 - do not add trailing empty lines to source files
4846 Submissions which do not conform to the standards may be returned
4847 with a request to reformat the changes.
4850 Submitting Patches:
4851 -------------------
4853 Since the number of patches for U-Boot is growing, we need to
4854 establish some rules. Submissions which do not conform to these rules
4855 may be rejected, even when they contain important and valuable stuff.
4857 Please see http://www.denx.de/wiki/U-Boot/Patches for details.
4859 Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>;
4860 see http://lists.denx.de/mailman/listinfo/u-boot
4862 When you send a patch, please include the following information with
4863 it:
4865 * For bug fixes: a description of the bug and how your patch fixes
4866 this bug. Please try to include a way of demonstrating that the
4867 patch actually fixes something.
4869 * For new features: a description of the feature and your
4870 implementation.
4872 * A CHANGELOG entry as plaintext (separate from the patch)
4874 * For major contributions, your entry to the CREDITS file
4876 * When you add support for a new board, don't forget to add this
4877 board to the MAINTAINERS file, too.
4879 * If your patch adds new configuration options, don't forget to
4880 document these in the README file.
4882 * The patch itself. If you are using git (which is *strongly*
4883 recommended) you can easily generate the patch using the
4884 "git format-patch". If you then use "git send-email" to send it to
4885 the U-Boot mailing list, you will avoid most of the common problems
4886 with some other mail clients.
4888 If you cannot use git, use "diff -purN OLD NEW". If your version of
4889 diff does not support these options, then get the latest version of
4890 GNU diff.
4892 The current directory when running this command shall be the parent
4893 directory of the U-Boot source tree (i. e. please make sure that
4894 your patch includes sufficient directory information for the
4895 affected files).
4897 We prefer patches as plain text. MIME attachments are discouraged,
4898 and compressed attachments must not be used.
4900 * If one logical set of modifications affects or creates several
4901 files, all these changes shall be submitted in a SINGLE patch file.
4903 * Changesets that contain different, unrelated modifications shall be
4904 submitted as SEPARATE patches, one patch per changeset.
4907 Notes:
4909 * Before sending the patch, run the MAKEALL script on your patched
4910 source tree and make sure that no errors or warnings are reported
4911 for any of the boards.
4913 * Keep your modifications to the necessary minimum: A patch
4914 containing several unrelated changes or arbitrary reformats will be
4915 returned with a request to re-formatting / split it.
4917 * If you modify existing code, make sure that your new code does not
4918 add to the memory footprint of the code ;-) Small is beautiful!
4919 When adding new features, these should compile conditionally only
4920 (using #ifdef), and the resulting code with the new feature
4921 disabled must not need more memory than the old code without your
4922 modification.
4924 * Remember that there is a size limit of 100 kB per message on the
4925 u-boot mailing list. Bigger patches will be moderated. If they are
4926 reasonable and not too big, they will be acknowledged. But patches
4927 bigger than the size limit should be avoided.