2 # (C) Copyright 2000 - 2008
3 # Wolfgang Denk, DENX Software Engineering, wd@denx.de.
5 # See file CREDITS for list of people who contributed to this
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.
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.
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,
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
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.
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
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/
81 Pre-built (and tested) images are available from
82 ftp://ftp.denx.de/pub/u-boot/images/
88 - start from 8xxrom sources
89 - create PPCBoot project (http://sourceforge.net/projects/ppcboot)
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
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
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
129 U-Boot uses a 3 level version number containing a version, a
130 sub-version, and a patchlevel: "U-Boot-2.34.5" means version "2",
131 sub-version "34", and patchlevel "4".
133 The patchlevel is used to indicate certain stages of development
134 between released versions, i. e. officially released versions of
135 U-Boot will always have a patchlevel of "0".
141 - board Board dependent files
142 - common Misc architecture independent functions
143 - cpu CPU specific files
144 - 74xx_7xx Files specific to Freescale MPC74xx and 7xx CPUs
145 - arm720t Files specific to ARM 720 CPUs
146 - arm920t Files specific to ARM 920 CPUs
147 - at91rm9200 Files specific to Atmel AT91RM9200 CPU
148 - imx Files specific to Freescale MC9328 i.MX CPUs
149 - s3c24x0 Files specific to Samsung S3C24X0 CPUs
150 - arm925t Files specific to ARM 925 CPUs
151 - arm926ejs Files specific to ARM 926 CPUs
152 - arm1136 Files specific to ARM 1136 CPUs
153 - at32ap Files specific to Atmel AVR32 AP CPUs
154 - blackfin Files specific to Analog Devices Blackfin CPUs
155 - i386 Files specific to i386 CPUs
156 - ixp Files specific to Intel XScale IXP CPUs
157 - leon2 Files specific to Gaisler LEON2 SPARC CPU
158 - leon3 Files specific to Gaisler LEON3 SPARC CPU
159 - mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs
160 - mcf5227x Files specific to Freescale ColdFire MCF5227x CPUs
161 - mcf532x Files specific to Freescale ColdFire MCF5329 CPUs
162 - mcf5445x Files specific to Freescale ColdFire MCF5445x CPUs
163 - mcf547x_8x Files specific to Freescale ColdFire MCF547x_8x CPUs
164 - mips Files specific to MIPS CPUs
165 - mpc5xx Files specific to Freescale MPC5xx CPUs
166 - mpc5xxx Files specific to Freescale MPC5xxx CPUs
167 - mpc8xx Files specific to Freescale MPC8xx CPUs
168 - mpc8220 Files specific to Freescale MPC8220 CPUs
169 - mpc824x Files specific to Freescale MPC824x CPUs
170 - mpc8260 Files specific to Freescale MPC8260 CPUs
171 - mpc85xx Files specific to Freescale MPC85xx CPUs
172 - nios Files specific to Altera NIOS CPUs
173 - nios2 Files specific to Altera Nios-II CPUs
174 - ppc4xx Files specific to AMCC PowerPC 4xx CPUs
175 - pxa Files specific to Intel XScale PXA CPUs
176 - s3c44b0 Files specific to Samsung S3C44B0 CPUs
177 - sa1100 Files specific to Intel StrongARM SA1100 CPUs
178 - disk Code for disk drive partition handling
179 - doc Documentation (don't expect too much)
180 - drivers Commonly used device drivers
181 - dtt Digital Thermometer and Thermostat drivers
182 - examples Example code for standalone applications, etc.
183 - include Header Files
184 - lib_arm Files generic to ARM architecture
185 - lib_avr32 Files generic to AVR32 architecture
186 - lib_blackfin Files generic to Blackfin architecture
187 - lib_generic Files generic to all architectures
188 - lib_i386 Files generic to i386 architecture
189 - lib_m68k Files generic to m68k architecture
190 - lib_mips Files generic to MIPS architecture
191 - lib_nios Files generic to NIOS architecture
192 - lib_ppc Files generic to PowerPC architecture
193 - lib_sparc Files generic to SPARC architecture
194 - libfdt Library files to support flattened device trees
195 - net Networking code
196 - post Power On Self Test
197 - rtc Real Time Clock drivers
198 - tools Tools to build S-Record or U-Boot images, etc.
200 Software Configuration:
201 =======================
203 Configuration is usually done using C preprocessor defines; the
204 rationale behind that is to avoid dead code whenever possible.
206 There are two classes of configuration variables:
208 * Configuration _OPTIONS_:
209 These are selectable by the user and have names beginning with
212 * Configuration _SETTINGS_:
213 These depend on the hardware etc. and should not be meddled with if
214 you don't know what you're doing; they have names beginning with
217 Later we will add a configuration tool - probably similar to or even
218 identical to what's used for the Linux kernel. Right now, we have to
219 do the configuration by hand, which means creating some symbolic
220 links and editing some configuration files. We use the TQM8xxL boards
224 Selection of Processor Architecture and Board Type:
225 ---------------------------------------------------
227 For all supported boards there are ready-to-use default
228 configurations available; just type "make <board_name>_config".
230 Example: For a TQM823L module type:
235 For the Cogent platform, you need to specify the CPU type as well;
236 e.g. "make cogent_mpc8xx_config". And also configure the cogent
237 directory according to the instructions in cogent/README.
240 Configuration Options:
241 ----------------------
243 Configuration depends on the combination of board and CPU type; all
244 such information is kept in a configuration file
245 "include/configs/<board_name>.h".
247 Example: For a TQM823L module, all configuration settings are in
248 "include/configs/TQM823L.h".
251 Many of the options are named exactly as the corresponding Linux
252 kernel configuration options. The intention is to make it easier to
253 build a config tool - later.
256 The following options need to be configured:
258 - CPU Type: Define exactly one, e.g. CONFIG_MPC85XX.
260 - Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS.
262 - CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined)
263 Define exactly one, e.g. CONFIG_ATSTK1002
265 - CPU Module Type: (if CONFIG_COGENT is defined)
266 Define exactly one of
268 --- FIXME --- not tested yet:
269 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P,
270 CONFIG_CMA287_23, CONFIG_CMA287_50
272 - Motherboard Type: (if CONFIG_COGENT is defined)
273 Define exactly one of
274 CONFIG_CMA101, CONFIG_CMA102
276 - Motherboard I/O Modules: (if CONFIG_COGENT is defined)
277 Define one or more of
280 - Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined)
281 Define one or more of
282 CONFIG_LCD_HEARTBEAT - update a character position on
283 the LCD display every second with
286 - Board flavour: (if CONFIG_MPC8260ADS is defined)
289 CONFIG_SYS_8260ADS - original MPC8260ADS
290 CONFIG_SYS_8266ADS - MPC8266ADS
291 CONFIG_SYS_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR
292 CONFIG_SYS_8272ADS - MPC8272ADS
294 - MPC824X Family Member (if CONFIG_MPC824X is defined)
295 Define exactly one of
296 CONFIG_MPC8240, CONFIG_MPC8245
298 - 8xx CPU Options: (if using an MPC8xx CPU)
299 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if
300 get_gclk_freq() cannot work
301 e.g. if there is no 32KHz
302 reference PIT/RTC clock
303 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK
306 - 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU):
307 CONFIG_SYS_8xx_CPUCLK_MIN
308 CONFIG_SYS_8xx_CPUCLK_MAX
309 CONFIG_8xx_CPUCLK_DEFAULT
310 See doc/README.MPC866
312 CONFIG_SYS_MEASURE_CPUCLK
314 Define this to measure the actual CPU clock instead
315 of relying on the correctness of the configured
316 values. Mostly useful for board bringup to make sure
317 the PLL is locked at the intended frequency. Note
318 that this requires a (stable) reference clock (32 kHz
319 RTC clock or CONFIG_SYS_8XX_XIN)
321 CONFIG_SYS_DELAYED_ICACHE
323 Define this option if you want to enable the
324 ICache only when Code runs from RAM.
326 - Intel Monahans options:
327 CONFIG_SYS_MONAHANS_RUN_MODE_OSC_RATIO
329 Defines the Monahans run mode to oscillator
330 ratio. Valid values are 8, 16, 24, 31. The core
331 frequency is this value multiplied by 13 MHz.
333 CONFIG_SYS_MONAHANS_TURBO_RUN_MODE_RATIO
335 Defines the Monahans turbo mode to oscillator
336 ratio. Valid values are 1 (default if undefined) and
337 2. The core frequency as calculated above is multiplied
340 - Linux Kernel Interface:
343 U-Boot stores all clock information in Hz
344 internally. For binary compatibility with older Linux
345 kernels (which expect the clocks passed in the
346 bd_info data to be in MHz) the environment variable
347 "clocks_in_mhz" can be defined so that U-Boot
348 converts clock data to MHZ before passing it to the
350 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
351 "clocks_in_mhz=1" is automatically included in the
354 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
356 When transferring memsize parameter to linux, some versions
357 expect it to be in bytes, others in MB.
358 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
362 New kernel versions are expecting firmware settings to be
363 passed using flattened device trees (based on open firmware
367 * New libfdt-based support
368 * Adds the "fdt" command
369 * The bootm command automatically updates the fdt
371 OF_CPU - The proper name of the cpus node (only required for
372 MPC512X and MPC5xxx based boards).
373 OF_SOC - The proper name of the soc node (only required for
374 MPC512X and MPC5xxx based boards).
375 OF_TBCLK - The timebase frequency.
376 OF_STDOUT_PATH - The path to the console device
378 boards with QUICC Engines require OF_QE to set UCC MAC
381 CONFIG_OF_BOARD_SETUP
383 Board code has addition modification that it wants to make
384 to the flat device tree before handing it off to the kernel
388 This define fills in the correct boot CPU in the boot
389 param header, the default value is zero if undefined.
393 U-Boot can detect if an IDE device is present or not.
394 If not, and this new config option is activated, U-Boot
395 removes the ATA node from the DTS before booting Linux,
396 so the Linux IDE driver does not probe the device and
397 crash. This is needed for buggy hardware (uc101) where
398 no pull down resistor is connected to the signal IDE5V_DD7.
400 - vxWorks boot parameters:
402 bootvx constructs a valid bootline using the following
403 environments variables: bootfile, ipaddr, serverip, hostname.
404 It loads the vxWorks image pointed bootfile.
406 CONFIG_SYS_VXWORKS_BOOT_DEVICE - The vxworks device name
407 CONFIG_SYS_VXWORKS_MAC_PTR - Ethernet 6 byte MA -address
408 CONFIG_SYS_VXWORKS_SERVERNAME - Name of the server
409 CONFIG_SYS_VXWORKS_BOOT_ADDR - Address of boot parameters
411 CONFIG_SYS_VXWORKS_ADD_PARAMS
413 Add it at the end of the bootline. E.g "u=username pw=secret"
415 Note: If a "bootargs" environment is defined, it will overwride
416 the defaults discussed just above.
421 Define this if you want support for Amba PrimeCell PL010 UARTs.
425 Define this if you want support for Amba PrimeCell PL011 UARTs.
429 If you have Amba PrimeCell PL011 UARTs, set this variable to
430 the clock speed of the UARTs.
434 If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
435 define this to a list of base addresses for each (supported)
436 port. See e.g. include/configs/versatile.h
440 Depending on board, define exactly one serial port
441 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
442 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial
443 console by defining CONFIG_8xx_CONS_NONE
445 Note: if CONFIG_8xx_CONS_NONE is defined, the serial
446 port routines must be defined elsewhere
447 (i.e. serial_init(), serial_getc(), ...)
450 Enables console device for a color framebuffer. Needs following
451 defines (cf. smiLynxEM, i8042, board/eltec/bab7xx)
452 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation
454 VIDEO_HW_RECTFILL graphic chip supports
457 VIDEO_HW_BITBLT graphic chip supports
458 bit-blit (cf. smiLynxEM)
459 VIDEO_VISIBLE_COLS visible pixel columns
461 VIDEO_VISIBLE_ROWS visible pixel rows
462 VIDEO_PIXEL_SIZE bytes per pixel
463 VIDEO_DATA_FORMAT graphic data format
464 (0-5, cf. cfb_console.c)
465 VIDEO_FB_ADRS framebuffer address
466 VIDEO_KBD_INIT_FCT keyboard int fct
467 (i.e. i8042_kbd_init())
468 VIDEO_TSTC_FCT test char fct
470 VIDEO_GETC_FCT get char fct
472 CONFIG_CONSOLE_CURSOR cursor drawing on/off
473 (requires blink timer
475 CONFIG_SYS_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c)
476 CONFIG_CONSOLE_TIME display time/date info in
478 (requires CONFIG_CMD_DATE)
479 CONFIG_VIDEO_LOGO display Linux logo in
481 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of
482 linux_logo.h for logo.
483 Requires CONFIG_VIDEO_LOGO
484 CONFIG_CONSOLE_EXTRA_INFO
485 additional board info beside
488 When CONFIG_CFB_CONSOLE is defined, video console is
489 default i/o. Serial console can be forced with
490 environment 'console=serial'.
492 When CONFIG_SILENT_CONSOLE is defined, all console
493 messages (by U-Boot and Linux!) can be silenced with
494 the "silent" environment variable. See
495 doc/README.silent for more information.
498 CONFIG_BAUDRATE - in bps
499 Select one of the baudrates listed in
500 CONFIG_SYS_BAUDRATE_TABLE, see below.
501 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale
503 - Console Rx buffer length
504 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define
505 the maximum receive buffer length for the SMC.
506 This option is actual only for 82xx and 8xx possible.
507 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE
508 must be defined, to setup the maximum idle timeout for
511 - Interrupt driven serial port input:
512 CONFIG_SERIAL_SOFTWARE_FIFO
515 Use an interrupt handler for receiving data on the
516 serial port. It also enables using hardware handshake
517 (RTS/CTS) and UART's built-in FIFO. Set the number of
518 bytes the interrupt driven input buffer should have.
520 Leave undefined to disable this feature, including
521 disable the buffer and hardware handshake.
523 - Console UART Number:
527 If defined internal UART1 (and not UART0) is used
528 as default U-Boot console.
530 - Boot Delay: CONFIG_BOOTDELAY - in seconds
531 Delay before automatically booting the default image;
532 set to -1 to disable autoboot.
534 See doc/README.autoboot for these options that
535 work with CONFIG_BOOTDELAY. None are required.
536 CONFIG_BOOT_RETRY_TIME
537 CONFIG_BOOT_RETRY_MIN
538 CONFIG_AUTOBOOT_KEYED
539 CONFIG_AUTOBOOT_PROMPT
540 CONFIG_AUTOBOOT_DELAY_STR
541 CONFIG_AUTOBOOT_STOP_STR
542 CONFIG_AUTOBOOT_DELAY_STR2
543 CONFIG_AUTOBOOT_STOP_STR2
544 CONFIG_ZERO_BOOTDELAY_CHECK
545 CONFIG_RESET_TO_RETRY
549 Only needed when CONFIG_BOOTDELAY is enabled;
550 define a command string that is automatically executed
551 when no character is read on the console interface
552 within "Boot Delay" after reset.
555 This can be used to pass arguments to the bootm
556 command. The value of CONFIG_BOOTARGS goes into the
557 environment value "bootargs".
559 CONFIG_RAMBOOT and CONFIG_NFSBOOT
560 The value of these goes into the environment as
561 "ramboot" and "nfsboot" respectively, and can be used
562 as a convenience, when switching between booting from
568 When this option is #defined, the existence of the
569 environment variable "preboot" will be checked
570 immediately before starting the CONFIG_BOOTDELAY
571 countdown and/or running the auto-boot command resp.
572 entering interactive mode.
574 This feature is especially useful when "preboot" is
575 automatically generated or modified. For an example
576 see the LWMON board specific code: here "preboot" is
577 modified when the user holds down a certain
578 combination of keys on the (special) keyboard when
581 - Serial Download Echo Mode:
583 If defined to 1, all characters received during a
584 serial download (using the "loads" command) are
585 echoed back. This might be needed by some terminal
586 emulations (like "cu"), but may as well just take
587 time on others. This setting #define's the initial
588 value of the "loads_echo" environment variable.
590 - Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined)
592 Select one of the baudrates listed in
593 CONFIG_SYS_BAUDRATE_TABLE, see below.
596 Monitor commands can be included or excluded
597 from the build by using the #include files
598 "config_cmd_all.h" and #undef'ing unwanted
599 commands, or using "config_cmd_default.h"
600 and augmenting with additional #define's
603 The default command configuration includes all commands
604 except those marked below with a "*".
606 CONFIG_CMD_ASKENV * ask for env variable
607 CONFIG_CMD_BDI bdinfo
608 CONFIG_CMD_BEDBUG * Include BedBug Debugger
609 CONFIG_CMD_BMP * BMP support
610 CONFIG_CMD_BSP * Board specific commands
611 CONFIG_CMD_BOOTD bootd
612 CONFIG_CMD_CACHE * icache, dcache
613 CONFIG_CMD_CONSOLE coninfo
614 CONFIG_CMD_DATE * support for RTC, date/time...
615 CONFIG_CMD_DHCP * DHCP support
616 CONFIG_CMD_DIAG * Diagnostics
617 CONFIG_CMD_DS4510 * ds4510 I2C gpio commands
618 CONFIG_CMD_DS4510_INFO * ds4510 I2C info command
619 CONFIG_CMD_DS4510_MEM * ds4510 I2C eeprom/sram commansd
620 CONFIG_CMD_DS4510_RST * ds4510 I2C rst command
621 CONFIG_CMD_DTT * Digital Therm and Thermostat
622 CONFIG_CMD_ECHO echo arguments
623 CONFIG_CMD_EEPROM * EEPROM read/write support
624 CONFIG_CMD_ELF * bootelf, bootvx
625 CONFIG_CMD_SAVEENV saveenv
626 CONFIG_CMD_FDC * Floppy Disk Support
627 CONFIG_CMD_FAT * FAT partition support
628 CONFIG_CMD_FDOS * Dos diskette Support
629 CONFIG_CMD_FLASH flinfo, erase, protect
630 CONFIG_CMD_FPGA FPGA device initialization support
631 CONFIG_CMD_HWFLOW * RTS/CTS hw flow control
632 CONFIG_CMD_I2C * I2C serial bus support
633 CONFIG_CMD_IDE * IDE harddisk support
634 CONFIG_CMD_IMI iminfo
635 CONFIG_CMD_IMLS List all found images
636 CONFIG_CMD_IMMAP * IMMR dump support
637 CONFIG_CMD_IRQ * irqinfo
638 CONFIG_CMD_ITEST Integer/string test of 2 values
639 CONFIG_CMD_JFFS2 * JFFS2 Support
640 CONFIG_CMD_KGDB * kgdb
641 CONFIG_CMD_LOADB loadb
642 CONFIG_CMD_LOADS loads
643 CONFIG_CMD_MD5SUM print md5 message digest
644 (requires CONFIG_CMD_MEMORY and CONFIG_MD5)
645 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base,
647 CONFIG_CMD_MISC Misc functions like sleep etc
648 CONFIG_CMD_MMC * MMC memory mapped support
649 CONFIG_CMD_MII * MII utility commands
650 CONFIG_CMD_MTDPARTS * MTD partition support
651 CONFIG_CMD_NAND * NAND support
652 CONFIG_CMD_NET bootp, tftpboot, rarpboot
653 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands
654 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command
655 CONFIG_CMD_PCI * pciinfo
656 CONFIG_CMD_PCMCIA * PCMCIA support
657 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network
659 CONFIG_CMD_PORTIO * Port I/O
660 CONFIG_CMD_REGINFO * Register dump
661 CONFIG_CMD_RUN run command in env variable
662 CONFIG_CMD_SAVES * save S record dump
663 CONFIG_CMD_SCSI * SCSI Support
664 CONFIG_CMD_SDRAM * print SDRAM configuration information
665 (requires CONFIG_CMD_I2C)
666 CONFIG_CMD_SETGETDCR Support for DCR Register access
668 CONFIG_CMD_SHA1 print sha1 memory digest
669 (requires CONFIG_CMD_MEMORY)
670 CONFIG_CMD_SOURCE "source" command Support
671 CONFIG_CMD_SPI * SPI serial bus support
672 CONFIG_CMD_USB * USB support
673 CONFIG_CMD_VFD * VFD support (TRAB)
674 CONFIG_CMD_CDP * Cisco Discover Protocol support
675 CONFIG_CMD_FSL * Microblaze FSL support
678 EXAMPLE: If you want all functions except of network
679 support you can write:
681 #include "config_cmd_all.h"
682 #undef CONFIG_CMD_NET
685 fdt (flattened device tree) command: CONFIG_OF_LIBFDT
687 Note: Don't enable the "icache" and "dcache" commands
688 (configuration option CONFIG_CMD_CACHE) unless you know
689 what you (and your U-Boot users) are doing. Data
690 cache cannot be enabled on systems like the 8xx or
691 8260 (where accesses to the IMMR region must be
692 uncached), and it cannot be disabled on all other
693 systems where we (mis-) use the data cache to hold an
694 initial stack and some data.
697 XXX - this list needs to get updated!
701 If this variable is defined, it enables watchdog
702 support. There must be support in the platform specific
703 code for a watchdog. For the 8xx and 8260 CPUs, the
704 SIU Watchdog feature is enabled in the SYPCR
708 CONFIG_VERSION_VARIABLE
709 If this variable is defined, an environment variable
710 named "ver" is created by U-Boot showing the U-Boot
711 version as printed by the "version" command.
712 This variable is readonly.
716 When CONFIG_CMD_DATE is selected, the type of the RTC
717 has to be selected, too. Define exactly one of the
720 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx
721 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
722 CONFIG_RTC_MC13783 - use MC13783 RTC
723 CONFIG_RTC_MC146818 - use MC146818 RTC
724 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
725 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
726 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
727 CONFIG_RTC_DS164x - use Dallas DS164x RTC
728 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC
729 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
730 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337
732 Note that if the RTC uses I2C, then the I2C interface
733 must also be configured. See I2C Support, below.
736 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO
737 CONFIG_PCA953X_INFO - enable pca953x info command
739 Note that if the GPIO device uses I2C, then the I2C interface
740 must also be configured. See I2C Support, below.
744 When CONFIG_TIMESTAMP is selected, the timestamp
745 (date and time) of an image is printed by image
746 commands like bootm or iminfo. This option is
747 automatically enabled when you select CONFIG_CMD_DATE .
750 CONFIG_MAC_PARTITION and/or CONFIG_DOS_PARTITION
751 and/or CONFIG_ISO_PARTITION and/or CONFIG_EFI_PARTITION
753 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or
754 CONFIG_CMD_SCSI) you must configure support for at
755 least one partition type as well.
758 CONFIG_IDE_RESET_ROUTINE - this is defined in several
759 board configurations files but used nowhere!
761 CONFIG_IDE_RESET - is this is defined, IDE Reset will
762 be performed by calling the function
763 ide_set_reset(int reset)
764 which has to be defined in a board specific file
769 Set this to enable ATAPI support.
774 Set this to enable support for disks larger than 137GB
775 Also look at CONFIG_SYS_64BIT_LBA ,CONFIG_SYS_64BIT_VSPRINTF and CONFIG_SYS_64BIT_STRTOUL
776 Whithout these , LBA48 support uses 32bit variables and will 'only'
777 support disks up to 2.1TB.
779 CONFIG_SYS_64BIT_LBA:
780 When enabled, makes the IDE subsystem use 64bit sector addresses.
784 At the moment only there is only support for the
785 SYM53C8XX SCSI controller; define
786 CONFIG_SCSI_SYM53C8XX to enable it.
788 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and
789 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID *
790 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the
791 maximum numbers of LUNs, SCSI ID's and target
793 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
795 - NETWORK Support (PCI):
797 Support for Intel 8254x gigabit chips.
799 CONFIG_E1000_FALLBACK_MAC
800 default MAC for empty EEPROM after production.
803 Support for Intel 82557/82559/82559ER chips.
804 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM
805 write routine for first time initialisation.
808 Support for Digital 2114x chips.
809 Optional CONFIG_TULIP_SELECT_MEDIA for board specific
810 modem chip initialisation (KS8761/QS6611).
813 Support for National dp83815 chips.
816 Support for National dp8382[01] gigabit chips.
818 - NETWORK Support (other):
820 CONFIG_DRIVER_LAN91C96
821 Support for SMSC's LAN91C96 chips.
824 Define this to hold the physical address
825 of the LAN91C96's I/O space
827 CONFIG_LAN91C96_USE_32_BIT
828 Define this to enable 32 bit addressing
830 CONFIG_DRIVER_SMC91111
831 Support for SMSC's LAN91C111 chip
834 Define this to hold the physical address
835 of the device (I/O space)
837 CONFIG_SMC_USE_32_BIT
838 Define this if data bus is 32 bits
840 CONFIG_SMC_USE_IOFUNCS
841 Define this to use i/o functions instead of macros
842 (some hardware wont work with macros)
844 CONFIG_DRIVER_SMC911X
845 Support for SMSC's LAN911x and LAN921x chips
847 CONFIG_DRIVER_SMC911X_BASE
848 Define this to hold the physical address
849 of the device (I/O space)
851 CONFIG_DRIVER_SMC911X_32_BIT
852 Define this if data bus is 32 bits
854 CONFIG_DRIVER_SMC911X_16_BIT
855 Define this if data bus is 16 bits. If your processor
856 automatically converts one 32 bit word to two 16 bit
857 words you may also try CONFIG_DRIVER_SMC911X_32_BIT.
860 At the moment only the UHCI host controller is
861 supported (PIP405, MIP405, MPC5200); define
862 CONFIG_USB_UHCI to enable it.
863 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
864 and define CONFIG_USB_STORAGE to enable the USB
867 Supported are USB Keyboards and USB Floppy drives
869 MPC5200 USB requires additional defines:
871 for 528 MHz Clock: 0x0001bbbb
875 for differential drivers: 0x00001000
876 for single ended drivers: 0x00005000
877 for differential drivers on PSC3: 0x00000100
878 for single ended drivers on PSC3: 0x00004100
879 CONFIG_SYS_USB_EVENT_POLL
880 May be defined to allow interrupt polling
881 instead of using asynchronous interrupts
884 Define the below if you wish to use the USB console.
885 Once firmware is rebuilt from a serial console issue the
886 command "setenv stdin usbtty; setenv stdout usbtty" and
887 attach your USB cable. The Unix command "dmesg" should print
888 it has found a new device. The environment variable usbtty
889 can be set to gserial or cdc_acm to enable your device to
890 appear to a USB host as a Linux gserial device or a
891 Common Device Class Abstract Control Model serial device.
892 If you select usbtty = gserial you should be able to enumerate
894 # modprobe usbserial vendor=0xVendorID product=0xProductID
895 else if using cdc_acm, simply setting the environment
896 variable usbtty to be cdc_acm should suffice. The following
897 might be defined in YourBoardName.h
900 Define this to build a UDC device
903 Define this to have a tty type of device available to
904 talk to the UDC device
906 CONFIG_SYS_CONSOLE_IS_IN_ENV
907 Define this if you want stdin, stdout &/or stderr to
911 CONFIG_SYS_USB_EXTC_CLK 0xBLAH
912 Derive USB clock from external clock "blah"
913 - CONFIG_SYS_USB_EXTC_CLK 0x02
915 CONFIG_SYS_USB_BRG_CLK 0xBLAH
916 Derive USB clock from brgclk
917 - CONFIG_SYS_USB_BRG_CLK 0x04
919 If you have a USB-IF assigned VendorID then you may wish to
920 define your own vendor specific values either in BoardName.h
921 or directly in usbd_vendor_info.h. If you don't define
922 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME,
923 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot
924 should pretend to be a Linux device to it's target host.
926 CONFIG_USBD_MANUFACTURER
927 Define this string as the name of your company for
928 - CONFIG_USBD_MANUFACTURER "my company"
930 CONFIG_USBD_PRODUCT_NAME
931 Define this string as the name of your product
932 - CONFIG_USBD_PRODUCT_NAME "acme usb device"
935 Define this as your assigned Vendor ID from the USB
936 Implementors Forum. This *must* be a genuine Vendor ID
937 to avoid polluting the USB namespace.
938 - CONFIG_USBD_VENDORID 0xFFFF
940 CONFIG_USBD_PRODUCTID
941 Define this as the unique Product ID
943 - CONFIG_USBD_PRODUCTID 0xFFFF
947 The MMC controller on the Intel PXA is supported. To
948 enable this define CONFIG_MMC. The MMC can be
949 accessed from the boot prompt by mapping the device
950 to physical memory similar to flash. Command line is
951 enabled with CONFIG_CMD_MMC. The MMC driver also works with
952 the FAT fs. This is enabled with CONFIG_CMD_FAT.
954 - Journaling Flash filesystem support:
955 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE,
956 CONFIG_JFFS2_NAND_DEV
957 Define these for a default partition on a NAND device
959 CONFIG_SYS_JFFS2_FIRST_SECTOR,
960 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS
961 Define these for a default partition on a NOR device
963 CONFIG_SYS_JFFS_CUSTOM_PART
964 Define this to create an own partition. You have to provide a
965 function struct part_info* jffs2_part_info(int part_num)
967 If you define only one JFFS2 partition you may also want to
968 #define CONFIG_SYS_JFFS_SINGLE_PART 1
969 to disable the command chpart. This is the default when you
970 have not defined a custom partition
975 Define this to enable standard (PC-Style) keyboard
979 Standard PC keyboard driver with US (is default) and
980 GERMAN key layout (switch via environment 'keymap=de') support.
981 Export function i8042_kbd_init, i8042_tstc and i8042_getc
982 for cfb_console. Supports cursor blinking.
987 Define this to enable video support (for output to
992 Enable Chips & Technologies 69000 Video chip
994 CONFIG_VIDEO_SMI_LYNXEM
995 Enable Silicon Motion SMI 712/710/810 Video chip. The
996 video output is selected via environment 'videoout'
997 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is
1000 For the CT69000 and SMI_LYNXEM drivers, videomode is
1001 selected via environment 'videomode'. Two different ways
1003 - "videomode=num" 'num' is a standard LiLo mode numbers.
1004 Following standard modes are supported (* is default):
1006 Colors 640x480 800x600 1024x768 1152x864 1280x1024
1007 -------------+---------------------------------------------
1008 8 bits | 0x301* 0x303 0x305 0x161 0x307
1009 15 bits | 0x310 0x313 0x316 0x162 0x319
1010 16 bits | 0x311 0x314 0x317 0x163 0x31A
1011 24 bits | 0x312 0x315 0x318 ? 0x31B
1012 -------------+---------------------------------------------
1013 (i.e. setenv videomode 317; saveenv; reset;)
1015 - "videomode=bootargs" all the video parameters are parsed
1016 from the bootargs. (See drivers/video/videomodes.c)
1019 CONFIG_VIDEO_SED13806
1020 Enable Epson SED13806 driver. This driver supports 8bpp
1021 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
1022 or CONFIG_VIDEO_SED13806_16BPP
1027 Define this to enable a custom keyboard support.
1028 This simply calls drv_keyboard_init() which must be
1029 defined in your board-specific files.
1030 The only board using this so far is RBC823.
1032 - LCD Support: CONFIG_LCD
1034 Define this to enable LCD support (for output to LCD
1035 display); also select one of the supported displays
1036 by defining one of these:
1040 HITACHI TX09D70VM1CCA, 3.5", 240x320.
1042 CONFIG_NEC_NL6448AC33:
1044 NEC NL6448AC33-18. Active, color, single scan.
1046 CONFIG_NEC_NL6448BC20
1048 NEC NL6448BC20-08. 6.5", 640x480.
1049 Active, color, single scan.
1051 CONFIG_NEC_NL6448BC33_54
1053 NEC NL6448BC33-54. 10.4", 640x480.
1054 Active, color, single scan.
1058 Sharp 320x240. Active, color, single scan.
1059 It isn't 16x9, and I am not sure what it is.
1061 CONFIG_SHARP_LQ64D341
1063 Sharp LQ64D341 display, 640x480.
1064 Active, color, single scan.
1068 HLD1045 display, 640x480.
1069 Active, color, single scan.
1073 Optrex CBL50840-2 NF-FW 99 22 M5
1075 Hitachi LMG6912RPFC-00T
1079 320x240. Black & white.
1081 Normally display is black on white background; define
1082 CONFIG_SYS_WHITE_ON_BLACK to get it inverted.
1084 - Splash Screen Support: CONFIG_SPLASH_SCREEN
1086 If this option is set, the environment is checked for
1087 a variable "splashimage". If found, the usual display
1088 of logo, copyright and system information on the LCD
1089 is suppressed and the BMP image at the address
1090 specified in "splashimage" is loaded instead. The
1091 console is redirected to the "nulldev", too. This
1092 allows for a "silent" boot where a splash screen is
1093 loaded very quickly after power-on.
1095 CONFIG_SPLASH_SCREEN_ALIGN
1097 If this option is set the splash image can be freely positioned
1098 on the screen. Environment variable "splashpos" specifies the
1099 position as "x,y". If a positive number is given it is used as
1100 number of pixel from left/top. If a negative number is given it
1101 is used as number of pixel from right/bottom. You can also
1102 specify 'm' for centering the image.
1105 setenv splashpos m,m
1106 => image at center of screen
1108 setenv splashpos 30,20
1109 => image at x = 30 and y = 20
1111 setenv splashpos -10,m
1112 => vertically centered image
1113 at x = dspWidth - bmpWidth - 9
1115 - Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
1117 If this option is set, additionally to standard BMP
1118 images, gzipped BMP images can be displayed via the
1119 splashscreen support or the bmp command.
1121 - Compression support:
1124 If this option is set, support for bzip2 compressed
1125 images is included. If not, only uncompressed and gzip
1126 compressed images are supported.
1128 NOTE: the bzip2 algorithm requires a lot of RAM, so
1129 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should
1134 If this option is set, support for lzma compressed
1137 Note: The LZMA algorithm adds between 2 and 4KB of code and it
1138 requires an amount of dynamic memory that is given by the
1141 (1846 + 768 << (lc + lp)) * sizeof(uint16)
1143 Where lc and lp stand for, respectively, Literal context bits
1144 and Literal pos bits.
1146 This value is upper-bounded by 14MB in the worst case. Anyway,
1147 for a ~4MB large kernel image, we have lc=3 and lp=0 for a
1148 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is
1149 a very small buffer.
1151 Use the lzmainfo tool to determinate the lc and lp values and
1152 then calculate the amount of needed dynamic memory (ensuring
1153 the appropriate CONFIG_SYS_MALLOC_LEN value).
1158 The address of PHY on MII bus.
1160 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
1162 The clock frequency of the MII bus
1166 If this option is set, support for speed/duplex
1167 detection of gigabit PHY is included.
1169 CONFIG_PHY_RESET_DELAY
1171 Some PHY like Intel LXT971A need extra delay after
1172 reset before any MII register access is possible.
1173 For such PHY, set this option to the usec delay
1174 required. (minimum 300usec for LXT971A)
1176 CONFIG_PHY_CMD_DELAY (ppc4xx)
1178 Some PHY like Intel LXT971A need extra delay after
1179 command issued before MII status register can be read
1189 Define a default value for Ethernet address to use
1190 for the respective Ethernet interface, in case this
1191 is not determined automatically.
1196 Define a default value for the IP address to use for
1197 the default Ethernet interface, in case this is not
1198 determined through e.g. bootp.
1200 - Server IP address:
1203 Defines a default value for the IP address of a TFTP
1204 server to contact when using the "tftboot" command.
1206 CONFIG_KEEP_SERVERADDR
1208 Keeps the server's MAC address, in the env 'serveraddr'
1209 for passing to bootargs (like Linux's netconsole option)
1211 - Multicast TFTP Mode:
1214 Defines whether you want to support multicast TFTP as per
1215 rfc-2090; for example to work with atftp. Lets lots of targets
1216 tftp down the same boot image concurrently. Note: the Ethernet
1217 driver in use must provide a function: mcast() to join/leave a
1220 CONFIG_BOOTP_RANDOM_DELAY
1221 - BOOTP Recovery Mode:
1222 CONFIG_BOOTP_RANDOM_DELAY
1224 If you have many targets in a network that try to
1225 boot using BOOTP, you may want to avoid that all
1226 systems send out BOOTP requests at precisely the same
1227 moment (which would happen for instance at recovery
1228 from a power failure, when all systems will try to
1229 boot, thus flooding the BOOTP server. Defining
1230 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
1231 inserted before sending out BOOTP requests. The
1232 following delays are inserted then:
1234 1st BOOTP request: delay 0 ... 1 sec
1235 2nd BOOTP request: delay 0 ... 2 sec
1236 3rd BOOTP request: delay 0 ... 4 sec
1238 BOOTP requests: delay 0 ... 8 sec
1240 - DHCP Advanced Options:
1241 You can fine tune the DHCP functionality by defining
1242 CONFIG_BOOTP_* symbols:
1244 CONFIG_BOOTP_SUBNETMASK
1245 CONFIG_BOOTP_GATEWAY
1246 CONFIG_BOOTP_HOSTNAME
1247 CONFIG_BOOTP_NISDOMAIN
1248 CONFIG_BOOTP_BOOTPATH
1249 CONFIG_BOOTP_BOOTFILESIZE
1252 CONFIG_BOOTP_SEND_HOSTNAME
1253 CONFIG_BOOTP_NTPSERVER
1254 CONFIG_BOOTP_TIMEOFFSET
1255 CONFIG_BOOTP_VENDOREX
1257 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip
1258 environment variable, not the BOOTP server.
1260 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
1261 serverip from a DHCP server, it is possible that more
1262 than one DNS serverip is offered to the client.
1263 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
1264 serverip will be stored in the additional environment
1265 variable "dnsip2". The first DNS serverip is always
1266 stored in the variable "dnsip", when CONFIG_BOOTP_DNS
1269 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
1270 to do a dynamic update of a DNS server. To do this, they
1271 need the hostname of the DHCP requester.
1272 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content
1273 of the "hostname" environment variable is passed as
1274 option 12 to the DHCP server.
1276 CONFIG_BOOTP_DHCP_REQUEST_DELAY
1278 A 32bit value in microseconds for a delay between
1279 receiving a "DHCP Offer" and sending the "DHCP Request".
1280 This fixes a problem with certain DHCP servers that don't
1281 respond 100% of the time to a "DHCP request". E.g. On an
1282 AT91RM9200 processor running at 180MHz, this delay needed
1283 to be *at least* 15,000 usec before a Windows Server 2003
1284 DHCP server would reply 100% of the time. I recommend at
1285 least 50,000 usec to be safe. The alternative is to hope
1286 that one of the retries will be successful but note that
1287 the DHCP timeout and retry process takes a longer than
1291 CONFIG_CDP_DEVICE_ID
1293 The device id used in CDP trigger frames.
1295 CONFIG_CDP_DEVICE_ID_PREFIX
1297 A two character string which is prefixed to the MAC address
1302 A printf format string which contains the ascii name of
1303 the port. Normally is set to "eth%d" which sets
1304 eth0 for the first Ethernet, eth1 for the second etc.
1306 CONFIG_CDP_CAPABILITIES
1308 A 32bit integer which indicates the device capabilities;
1309 0x00000010 for a normal host which does not forwards.
1313 An ascii string containing the version of the software.
1317 An ascii string containing the name of the platform.
1321 A 32bit integer sent on the trigger.
1323 CONFIG_CDP_POWER_CONSUMPTION
1325 A 16bit integer containing the power consumption of the
1326 device in .1 of milliwatts.
1328 CONFIG_CDP_APPLIANCE_VLAN_TYPE
1330 A byte containing the id of the VLAN.
1332 - Status LED: CONFIG_STATUS_LED
1334 Several configurations allow to display the current
1335 status using a LED. For instance, the LED will blink
1336 fast while running U-Boot code, stop blinking as
1337 soon as a reply to a BOOTP request was received, and
1338 start blinking slow once the Linux kernel is running
1339 (supported by a status LED driver in the Linux
1340 kernel). Defining CONFIG_STATUS_LED enables this
1343 - CAN Support: CONFIG_CAN_DRIVER
1345 Defining CONFIG_CAN_DRIVER enables CAN driver support
1346 on those systems that support this (optional)
1347 feature, like the TQM8xxL modules.
1349 - I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C
1351 These enable I2C serial bus commands. Defining either of
1352 (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will
1353 include the appropriate I2C driver for the selected CPU.
1355 This will allow you to use i2c commands at the u-boot
1356 command line (as long as you set CONFIG_CMD_I2C in
1357 CONFIG_COMMANDS) and communicate with i2c based realtime
1358 clock chips. See common/cmd_i2c.c for a description of the
1359 command line interface.
1361 CONFIG_HARD_I2C selects a hardware I2C controller.
1363 CONFIG_SOFT_I2C configures u-boot to use a software (aka
1364 bit-banging) driver instead of CPM or similar hardware
1367 There are several other quantities that must also be
1368 defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C.
1370 In both cases you will need to define CONFIG_SYS_I2C_SPEED
1371 to be the frequency (in Hz) at which you wish your i2c bus
1372 to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie
1373 the CPU's i2c node address).
1375 Now, the u-boot i2c code for the mpc8xx (cpu/mpc8xx/i2c.c)
1376 sets the CPU up as a master node and so its address should
1377 therefore be cleared to 0 (See, eg, MPC823e User's Manual
1378 p.16-473). So, set CONFIG_SYS_I2C_SLAVE to 0.
1380 CONFIG_SYS_I2C_INIT_MPC5XXX
1382 When a board is reset during an i2c bus transfer
1383 chips might think that the current transfer is still
1384 in progress. Reset the slave devices by sending start
1385 commands until the slave device responds.
1387 That's all that's required for CONFIG_HARD_I2C.
1389 If you use the software i2c interface (CONFIG_SOFT_I2C)
1390 then the following macros need to be defined (examples are
1391 from include/configs/lwmon.h):
1395 (Optional). Any commands necessary to enable the I2C
1396 controller or configure ports.
1398 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
1402 (Only for MPC8260 CPU). The I/O port to use (the code
1403 assumes both bits are on the same port). Valid values
1404 are 0..3 for ports A..D.
1408 The code necessary to make the I2C data line active
1409 (driven). If the data line is open collector, this
1412 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
1416 The code necessary to make the I2C data line tri-stated
1417 (inactive). If the data line is open collector, this
1420 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
1424 Code that returns TRUE if the I2C data line is high,
1427 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
1431 If <bit> is TRUE, sets the I2C data line high. If it
1432 is FALSE, it clears it (low).
1434 eg: #define I2C_SDA(bit) \
1435 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
1436 else immr->im_cpm.cp_pbdat &= ~PB_SDA
1440 If <bit> is TRUE, sets the I2C clock line high. If it
1441 is FALSE, it clears it (low).
1443 eg: #define I2C_SCL(bit) \
1444 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
1445 else immr->im_cpm.cp_pbdat &= ~PB_SCL
1449 This delay is invoked four times per clock cycle so this
1450 controls the rate of data transfer. The data rate thus
1451 is 1 / (I2C_DELAY * 4). Often defined to be something
1454 #define I2C_DELAY udelay(2)
1456 CONFIG_SYS_I2C_INIT_BOARD
1458 When a board is reset during an i2c bus transfer
1459 chips might think that the current transfer is still
1460 in progress. On some boards it is possible to access
1461 the i2c SCLK line directly, either by using the
1462 processor pin as a GPIO or by having a second pin
1463 connected to the bus. If this option is defined a
1464 custom i2c_init_board() routine in boards/xxx/board.c
1465 is run early in the boot sequence.
1467 CONFIG_I2CFAST (PPC405GP|PPC405EP only)
1469 This option enables configuration of bi_iic_fast[] flags
1470 in u-boot bd_info structure based on u-boot environment
1471 variable "i2cfast". (see also i2cfast)
1473 CONFIG_I2C_MULTI_BUS
1475 This option allows the use of multiple I2C buses, each of which
1476 must have a controller. At any point in time, only one bus is
1477 active. To switch to a different bus, use the 'i2c dev' command.
1478 Note that bus numbering is zero-based.
1480 CONFIG_SYS_I2C_NOPROBES
1482 This option specifies a list of I2C devices that will be skipped
1483 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS
1484 is set, specify a list of bus-device pairs. Otherwise, specify
1485 a 1D array of device addresses
1488 #undef CONFIG_I2C_MULTI_BUS
1489 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68}
1491 will skip addresses 0x50 and 0x68 on a board with one I2C bus
1493 #define CONFIG_I2C_MULTI_BUS
1494 #define CONFIG_SYS_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}}
1496 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1
1498 CONFIG_SYS_SPD_BUS_NUM
1500 If defined, then this indicates the I2C bus number for DDR SPD.
1501 If not defined, then U-Boot assumes that SPD is on I2C bus 0.
1503 CONFIG_SYS_RTC_BUS_NUM
1505 If defined, then this indicates the I2C bus number for the RTC.
1506 If not defined, then U-Boot assumes that RTC is on I2C bus 0.
1508 CONFIG_SYS_DTT_BUS_NUM
1510 If defined, then this indicates the I2C bus number for the DTT.
1511 If not defined, then U-Boot assumes that DTT is on I2C bus 0.
1513 CONFIG_SYS_I2C_DTT_ADDR:
1515 If defined, specifies the I2C address of the DTT device.
1516 If not defined, then U-Boot uses predefined value for
1517 specified DTT device.
1521 Define this option if you want to use Freescale's I2C driver in
1522 drivers/i2c/fsl_i2c.c.
1526 Define this option if you have I2C devices reached over 1 .. n
1527 I2C Muxes like the pca9544a. This option addes a new I2C
1528 Command "i2c bus [muxtype:muxaddr:muxchannel]" which adds a
1529 new I2C Bus to the existing I2C Busses. If you select the
1530 new Bus with "i2c dev", u-bbot sends first the commandos for
1531 the muxes to activate this new "bus".
1533 CONFIG_I2C_MULTI_BUS must be also defined, to use this
1537 Adding a new I2C Bus reached over 2 pca9544a muxes
1538 The First mux with address 70 and channel 6
1539 The Second mux with address 71 and channel 4
1541 => i2c bus pca9544a:70:6:pca9544a:71:4
1543 Use the "i2c bus" command without parameter, to get a list
1544 of I2C Busses with muxes:
1547 Busses reached over muxes:
1549 reached over Mux(es):
1552 reached over Mux(es):
1557 If you now switch to the new I2C Bus 3 with "i2c dev 3"
1558 u-boot sends First the Commando to the mux@70 to enable
1559 channel 6, and then the Commando to the mux@71 to enable
1562 After that, you can use the "normal" i2c commands as
1563 usual, to communicate with your I2C devices behind
1566 This option is actually implemented for the bitbanging
1567 algorithm in common/soft_i2c.c and for the Hardware I2C
1568 Bus on the MPC8260. But it should be not so difficult
1569 to add this option to other architectures.
1571 CONFIG_SOFT_I2C_READ_REPEATED_START
1573 defining this will force the i2c_read() function in
1574 the soft_i2c driver to perform an I2C repeated start
1575 between writing the address pointer and reading the
1576 data. If this define is omitted the default behaviour
1577 of doing a stop-start sequence will be used. Most I2C
1578 devices can use either method, but some require one or
1581 - SPI Support: CONFIG_SPI
1583 Enables SPI driver (so far only tested with
1584 SPI EEPROM, also an instance works with Crystal A/D and
1585 D/As on the SACSng board)
1589 Enables extended (16-bit) SPI EEPROM addressing.
1590 (symmetrical to CONFIG_I2C_X)
1594 Enables a software (bit-bang) SPI driver rather than
1595 using hardware support. This is a general purpose
1596 driver that only requires three general I/O port pins
1597 (two outputs, one input) to function. If this is
1598 defined, the board configuration must define several
1599 SPI configuration items (port pins to use, etc). For
1600 an example, see include/configs/sacsng.h.
1604 Enables a hardware SPI driver for general-purpose reads
1605 and writes. As with CONFIG_SOFT_SPI, the board configuration
1606 must define a list of chip-select function pointers.
1607 Currently supported on some MPC8xxx processors. For an
1608 example, see include/configs/mpc8349emds.h.
1612 Enables the driver for the SPI controllers on i.MX and MXC
1613 SoCs. Currently only i.MX31 is supported.
1615 - FPGA Support: CONFIG_FPGA
1617 Enables FPGA subsystem.
1619 CONFIG_FPGA_<vendor>
1621 Enables support for specific chip vendors.
1624 CONFIG_FPGA_<family>
1626 Enables support for FPGA family.
1627 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
1631 Specify the number of FPGA devices to support.
1633 CONFIG_SYS_FPGA_PROG_FEEDBACK
1635 Enable printing of hash marks during FPGA configuration.
1637 CONFIG_SYS_FPGA_CHECK_BUSY
1639 Enable checks on FPGA configuration interface busy
1640 status by the configuration function. This option
1641 will require a board or device specific function to
1646 If defined, a function that provides delays in the FPGA
1647 configuration driver.
1649 CONFIG_SYS_FPGA_CHECK_CTRLC
1650 Allow Control-C to interrupt FPGA configuration
1652 CONFIG_SYS_FPGA_CHECK_ERROR
1654 Check for configuration errors during FPGA bitfile
1655 loading. For example, abort during Virtex II
1656 configuration if the INIT_B line goes low (which
1657 indicated a CRC error).
1659 CONFIG_SYS_FPGA_WAIT_INIT
1661 Maximum time to wait for the INIT_B line to deassert
1662 after PROB_B has been deasserted during a Virtex II
1663 FPGA configuration sequence. The default time is 500
1666 CONFIG_SYS_FPGA_WAIT_BUSY
1668 Maximum time to wait for BUSY to deassert during
1669 Virtex II FPGA configuration. The default is 5 ms.
1671 CONFIG_SYS_FPGA_WAIT_CONFIG
1673 Time to wait after FPGA configuration. The default is
1676 - Configuration Management:
1679 If defined, this string will be added to the U-Boot
1680 version information (U_BOOT_VERSION)
1682 - Vendor Parameter Protection:
1684 U-Boot considers the values of the environment
1685 variables "serial#" (Board Serial Number) and
1686 "ethaddr" (Ethernet Address) to be parameters that
1687 are set once by the board vendor / manufacturer, and
1688 protects these variables from casual modification by
1689 the user. Once set, these variables are read-only,
1690 and write or delete attempts are rejected. You can
1691 change this behaviour:
1693 If CONFIG_ENV_OVERWRITE is #defined in your config
1694 file, the write protection for vendor parameters is
1695 completely disabled. Anybody can change or delete
1698 Alternatively, if you #define _both_ CONFIG_ETHADDR
1699 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
1700 Ethernet address is installed in the environment,
1701 which can be changed exactly ONCE by the user. [The
1702 serial# is unaffected by this, i. e. it remains
1708 Define this variable to enable the reservation of
1709 "protected RAM", i. e. RAM which is not overwritten
1710 by U-Boot. Define CONFIG_PRAM to hold the number of
1711 kB you want to reserve for pRAM. You can overwrite
1712 this default value by defining an environment
1713 variable "pram" to the number of kB you want to
1714 reserve. Note that the board info structure will
1715 still show the full amount of RAM. If pRAM is
1716 reserved, a new environment variable "mem" will
1717 automatically be defined to hold the amount of
1718 remaining RAM in a form that can be passed as boot
1719 argument to Linux, for instance like that:
1721 setenv bootargs ... mem=\${mem}
1724 This way you can tell Linux not to use this memory,
1725 either, which results in a memory region that will
1726 not be affected by reboots.
1728 *WARNING* If your board configuration uses automatic
1729 detection of the RAM size, you must make sure that
1730 this memory test is non-destructive. So far, the
1731 following board configurations are known to be
1734 ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL,
1735 HERMES, IP860, RPXlite, LWMON, LANTEC,
1736 PCU_E, FLAGADM, TQM8260
1741 Define this variable to stop the system in case of a
1742 fatal error, so that you have to reset it manually.
1743 This is probably NOT a good idea for an embedded
1744 system where you want the system to reboot
1745 automatically as fast as possible, but it may be
1746 useful during development since you can try to debug
1747 the conditions that lead to the situation.
1749 CONFIG_NET_RETRY_COUNT
1751 This variable defines the number of retries for
1752 network operations like ARP, RARP, TFTP, or BOOTP
1753 before giving up the operation. If not defined, a
1754 default value of 5 is used.
1758 Timeout waiting for an ARP reply in milliseconds.
1760 - Command Interpreter:
1761 CONFIG_AUTO_COMPLETE
1763 Enable auto completion of commands using TAB.
1765 Note that this feature has NOT been implemented yet
1766 for the "hush" shell.
1769 CONFIG_SYS_HUSH_PARSER
1771 Define this variable to enable the "hush" shell (from
1772 Busybox) as command line interpreter, thus enabling
1773 powerful command line syntax like
1774 if...then...else...fi conditionals or `&&' and '||'
1775 constructs ("shell scripts").
1777 If undefined, you get the old, much simpler behaviour
1778 with a somewhat smaller memory footprint.
1781 CONFIG_SYS_PROMPT_HUSH_PS2
1783 This defines the secondary prompt string, which is
1784 printed when the command interpreter needs more input
1785 to complete a command. Usually "> ".
1789 In the current implementation, the local variables
1790 space and global environment variables space are
1791 separated. Local variables are those you define by
1792 simply typing `name=value'. To access a local
1793 variable later on, you have write `$name' or
1794 `${name}'; to execute the contents of a variable
1795 directly type `$name' at the command prompt.
1797 Global environment variables are those you use
1798 setenv/printenv to work with. To run a command stored
1799 in such a variable, you need to use the run command,
1800 and you must not use the '$' sign to access them.
1802 To store commands and special characters in a
1803 variable, please use double quotation marks
1804 surrounding the whole text of the variable, instead
1805 of the backslashes before semicolons and special
1808 - Commandline Editing and History:
1809 CONFIG_CMDLINE_EDITING
1811 Enable editing and History functions for interactive
1812 commandline input operations
1814 - Default Environment:
1815 CONFIG_EXTRA_ENV_SETTINGS
1817 Define this to contain any number of null terminated
1818 strings (variable = value pairs) that will be part of
1819 the default environment compiled into the boot image.
1821 For example, place something like this in your
1822 board's config file:
1824 #define CONFIG_EXTRA_ENV_SETTINGS \
1828 Warning: This method is based on knowledge about the
1829 internal format how the environment is stored by the
1830 U-Boot code. This is NOT an official, exported
1831 interface! Although it is unlikely that this format
1832 will change soon, there is no guarantee either.
1833 You better know what you are doing here.
1835 Note: overly (ab)use of the default environment is
1836 discouraged. Make sure to check other ways to preset
1837 the environment like the "source" command or the
1840 - DataFlash Support:
1841 CONFIG_HAS_DATAFLASH
1843 Defining this option enables DataFlash features and
1844 allows to read/write in Dataflash via the standard
1847 - SystemACE Support:
1850 Adding this option adds support for Xilinx SystemACE
1851 chips attached via some sort of local bus. The address
1852 of the chip must also be defined in the
1853 CONFIG_SYS_SYSTEMACE_BASE macro. For example:
1855 #define CONFIG_SYSTEMACE
1856 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000
1858 When SystemACE support is added, the "ace" device type
1859 becomes available to the fat commands, i.e. fatls.
1861 - TFTP Fixed UDP Port:
1864 If this is defined, the environment variable tftpsrcp
1865 is used to supply the TFTP UDP source port value.
1866 If tftpsrcp isn't defined, the normal pseudo-random port
1867 number generator is used.
1869 Also, the environment variable tftpdstp is used to supply
1870 the TFTP UDP destination port value. If tftpdstp isn't
1871 defined, the normal port 69 is used.
1873 The purpose for tftpsrcp is to allow a TFTP server to
1874 blindly start the TFTP transfer using the pre-configured
1875 target IP address and UDP port. This has the effect of
1876 "punching through" the (Windows XP) firewall, allowing
1877 the remainder of the TFTP transfer to proceed normally.
1878 A better solution is to properly configure the firewall,
1879 but sometimes that is not allowed.
1881 - Show boot progress:
1882 CONFIG_SHOW_BOOT_PROGRESS
1884 Defining this option allows to add some board-
1885 specific code (calling a user-provided function
1886 "show_boot_progress(int)") that enables you to show
1887 the system's boot progress on some display (for
1888 example, some LED's) on your board. At the moment,
1889 the following checkpoints are implemented:
1891 - Automatic software updates via TFTP server
1893 CONFIG_UPDATE_TFTP_CNT_MAX
1894 CONFIG_UPDATE_TFTP_MSEC_MAX
1896 These options enable and control the auto-update feature;
1897 for a more detailed description refer to doc/README.update.
1899 - MTD Support (mtdparts command, UBI support)
1902 Adds the MTD device infrastructure from the Linux kernel.
1903 Needed for mtdparts command support.
1905 CONFIG_MTD_PARTITIONS
1907 Adds the MTD partitioning infrastructure from the Linux
1908 kernel. Needed for UBI support.
1910 Legacy uImage format:
1913 1 common/cmd_bootm.c before attempting to boot an image
1914 -1 common/cmd_bootm.c Image header has bad magic number
1915 2 common/cmd_bootm.c Image header has correct magic number
1916 -2 common/cmd_bootm.c Image header has bad checksum
1917 3 common/cmd_bootm.c Image header has correct checksum
1918 -3 common/cmd_bootm.c Image data has bad checksum
1919 4 common/cmd_bootm.c Image data has correct checksum
1920 -4 common/cmd_bootm.c Image is for unsupported architecture
1921 5 common/cmd_bootm.c Architecture check OK
1922 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi)
1923 6 common/cmd_bootm.c Image Type check OK
1924 -6 common/cmd_bootm.c gunzip uncompression error
1925 -7 common/cmd_bootm.c Unimplemented compression type
1926 7 common/cmd_bootm.c Uncompression OK
1927 8 common/cmd_bootm.c No uncompress/copy overwrite error
1928 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
1930 9 common/image.c Start initial ramdisk verification
1931 -10 common/image.c Ramdisk header has bad magic number
1932 -11 common/image.c Ramdisk header has bad checksum
1933 10 common/image.c Ramdisk header is OK
1934 -12 common/image.c Ramdisk data has bad checksum
1935 11 common/image.c Ramdisk data has correct checksum
1936 12 common/image.c Ramdisk verification complete, start loading
1937 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk)
1938 13 common/image.c Start multifile image verification
1939 14 common/image.c No initial ramdisk, no multifile, continue.
1941 15 lib_<arch>/bootm.c All preparation done, transferring control to OS
1943 -30 lib_ppc/board.c Fatal error, hang the system
1944 -31 post/post.c POST test failed, detected by post_output_backlog()
1945 -32 post/post.c POST test failed, detected by post_run_single()
1947 34 common/cmd_doc.c before loading a Image from a DOC device
1948 -35 common/cmd_doc.c Bad usage of "doc" command
1949 35 common/cmd_doc.c correct usage of "doc" command
1950 -36 common/cmd_doc.c No boot device
1951 36 common/cmd_doc.c correct boot device
1952 -37 common/cmd_doc.c Unknown Chip ID on boot device
1953 37 common/cmd_doc.c correct chip ID found, device available
1954 -38 common/cmd_doc.c Read Error on boot device
1955 38 common/cmd_doc.c reading Image header from DOC device OK
1956 -39 common/cmd_doc.c Image header has bad magic number
1957 39 common/cmd_doc.c Image header has correct magic number
1958 -40 common/cmd_doc.c Error reading Image from DOC device
1959 40 common/cmd_doc.c Image header has correct magic number
1960 41 common/cmd_ide.c before loading a Image from a IDE device
1961 -42 common/cmd_ide.c Bad usage of "ide" command
1962 42 common/cmd_ide.c correct usage of "ide" command
1963 -43 common/cmd_ide.c No boot device
1964 43 common/cmd_ide.c boot device found
1965 -44 common/cmd_ide.c Device not available
1966 44 common/cmd_ide.c Device available
1967 -45 common/cmd_ide.c wrong partition selected
1968 45 common/cmd_ide.c partition selected
1969 -46 common/cmd_ide.c Unknown partition table
1970 46 common/cmd_ide.c valid partition table found
1971 -47 common/cmd_ide.c Invalid partition type
1972 47 common/cmd_ide.c correct partition type
1973 -48 common/cmd_ide.c Error reading Image Header on boot device
1974 48 common/cmd_ide.c reading Image Header from IDE device OK
1975 -49 common/cmd_ide.c Image header has bad magic number
1976 49 common/cmd_ide.c Image header has correct magic number
1977 -50 common/cmd_ide.c Image header has bad checksum
1978 50 common/cmd_ide.c Image header has correct checksum
1979 -51 common/cmd_ide.c Error reading Image from IDE device
1980 51 common/cmd_ide.c reading Image from IDE device OK
1981 52 common/cmd_nand.c before loading a Image from a NAND device
1982 -53 common/cmd_nand.c Bad usage of "nand" command
1983 53 common/cmd_nand.c correct usage of "nand" command
1984 -54 common/cmd_nand.c No boot device
1985 54 common/cmd_nand.c boot device found
1986 -55 common/cmd_nand.c Unknown Chip ID on boot device
1987 55 common/cmd_nand.c correct chip ID found, device available
1988 -56 common/cmd_nand.c Error reading Image Header on boot device
1989 56 common/cmd_nand.c reading Image Header from NAND device OK
1990 -57 common/cmd_nand.c Image header has bad magic number
1991 57 common/cmd_nand.c Image header has correct magic number
1992 -58 common/cmd_nand.c Error reading Image from NAND device
1993 58 common/cmd_nand.c reading Image from NAND device OK
1995 -60 common/env_common.c Environment has a bad CRC, using default
1997 64 net/eth.c starting with Ethernet configuration.
1998 -64 net/eth.c no Ethernet found.
1999 65 net/eth.c Ethernet found.
2001 -80 common/cmd_net.c usage wrong
2002 80 common/cmd_net.c before calling NetLoop()
2003 -81 common/cmd_net.c some error in NetLoop() occurred
2004 81 common/cmd_net.c NetLoop() back without error
2005 -82 common/cmd_net.c size == 0 (File with size 0 loaded)
2006 82 common/cmd_net.c trying automatic boot
2007 83 common/cmd_net.c running "source" command
2008 -83 common/cmd_net.c some error in automatic boot or "source" command
2009 84 common/cmd_net.c end without errors
2014 100 common/cmd_bootm.c Kernel FIT Image has correct format
2015 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format
2016 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration
2017 -101 common/cmd_bootm.c Can't get configuration for kernel subimage
2018 102 common/cmd_bootm.c Kernel unit name specified
2019 -103 common/cmd_bootm.c Can't get kernel subimage node offset
2020 103 common/cmd_bootm.c Found configuration node
2021 104 common/cmd_bootm.c Got kernel subimage node offset
2022 -104 common/cmd_bootm.c Kernel subimage hash verification failed
2023 105 common/cmd_bootm.c Kernel subimage hash verification OK
2024 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture
2025 106 common/cmd_bootm.c Architecture check OK
2026 -106 common/cmd_bootm.c Kernel subimage has wrong type
2027 107 common/cmd_bootm.c Kernel subimage type OK
2028 -107 common/cmd_bootm.c Can't get kernel subimage data/size
2029 108 common/cmd_bootm.c Got kernel subimage data/size
2030 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT)
2031 -109 common/cmd_bootm.c Can't get kernel subimage type
2032 -110 common/cmd_bootm.c Can't get kernel subimage comp
2033 -111 common/cmd_bootm.c Can't get kernel subimage os
2034 -112 common/cmd_bootm.c Can't get kernel subimage load address
2035 -113 common/cmd_bootm.c Image uncompress/copy overwrite error
2037 120 common/image.c Start initial ramdisk verification
2038 -120 common/image.c Ramdisk FIT image has incorrect format
2039 121 common/image.c Ramdisk FIT image has correct format
2040 122 common/image.c No ramdisk subimage unit name, using configuration
2041 -122 common/image.c Can't get configuration for ramdisk subimage
2042 123 common/image.c Ramdisk unit name specified
2043 -124 common/image.c Can't get ramdisk subimage node offset
2044 125 common/image.c Got ramdisk subimage node offset
2045 -125 common/image.c Ramdisk subimage hash verification failed
2046 126 common/image.c Ramdisk subimage hash verification OK
2047 -126 common/image.c Ramdisk subimage for unsupported architecture
2048 127 common/image.c Architecture check OK
2049 -127 common/image.c Can't get ramdisk subimage data/size
2050 128 common/image.c Got ramdisk subimage data/size
2051 129 common/image.c Can't get ramdisk load address
2052 -129 common/image.c Got ramdisk load address
2054 -130 common/cmd_doc.c Incorrect FIT image format
2055 131 common/cmd_doc.c FIT image format OK
2057 -140 common/cmd_ide.c Incorrect FIT image format
2058 141 common/cmd_ide.c FIT image format OK
2060 -150 common/cmd_nand.c Incorrect FIT image format
2061 151 common/cmd_nand.c FIT image format OK
2067 [so far only for SMDK2400 and TRAB boards]
2069 - Modem support enable:
2070 CONFIG_MODEM_SUPPORT
2072 - RTS/CTS Flow control enable:
2075 - Modem debug support:
2076 CONFIG_MODEM_SUPPORT_DEBUG
2078 Enables debugging stuff (char screen[1024], dbg())
2079 for modem support. Useful only with BDI2000.
2081 - Interrupt support (PPC):
2083 There are common interrupt_init() and timer_interrupt()
2084 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
2085 for CPU specific initialization. interrupt_init_cpu()
2086 should set decrementer_count to appropriate value. If
2087 CPU resets decrementer automatically after interrupt
2088 (ppc4xx) it should set decrementer_count to zero.
2089 timer_interrupt() calls timer_interrupt_cpu() for CPU
2090 specific handling. If board has watchdog / status_led
2091 / other_activity_monitor it works automatically from
2092 general timer_interrupt().
2096 In the target system modem support is enabled when a
2097 specific key (key combination) is pressed during
2098 power-on. Otherwise U-Boot will boot normally
2099 (autoboot). The key_pressed() function is called from
2100 board_init(). Currently key_pressed() is a dummy
2101 function, returning 1 and thus enabling modem
2104 If there are no modem init strings in the
2105 environment, U-Boot proceed to autoboot; the
2106 previous output (banner, info printfs) will be
2109 See also: doc/README.Modem
2112 Configuration Settings:
2113 -----------------------
2115 - CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
2116 undefine this when you're short of memory.
2118 - CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
2119 width of the commands listed in the 'help' command output.
2121 - CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to
2122 prompt for user input.
2124 - CONFIG_SYS_CBSIZE: Buffer size for input from the Console
2126 - CONFIG_SYS_PBSIZE: Buffer size for Console output
2128 - CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands
2130 - CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to
2131 the application (usually a Linux kernel) when it is
2134 - CONFIG_SYS_BAUDRATE_TABLE:
2135 List of legal baudrate settings for this board.
2137 - CONFIG_SYS_CONSOLE_INFO_QUIET
2138 Suppress display of console information at boot.
2140 - CONFIG_SYS_CONSOLE_IS_IN_ENV
2141 If the board specific function
2142 extern int overwrite_console (void);
2143 returns 1, the stdin, stderr and stdout are switched to the
2144 serial port, else the settings in the environment are used.
2146 - CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE
2147 Enable the call to overwrite_console().
2149 - CONFIG_SYS_CONSOLE_ENV_OVERWRITE
2150 Enable overwrite of previous console environment settings.
2152 - CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END:
2153 Begin and End addresses of the area used by the
2156 - CONFIG_SYS_ALT_MEMTEST:
2157 Enable an alternate, more extensive memory test.
2159 - CONFIG_SYS_MEMTEST_SCRATCH:
2160 Scratch address used by the alternate memory test
2161 You only need to set this if address zero isn't writeable
2163 - CONFIG_SYS_MEM_TOP_HIDE (PPC only):
2164 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header,
2165 this specified memory area will get subtracted from the top
2166 (end) of RAM and won't get "touched" at all by U-Boot. By
2167 fixing up gd->ram_size the Linux kernel should gets passed
2168 the now "corrected" memory size and won't touch it either.
2169 This should work for arch/ppc and arch/powerpc. Only Linux
2170 board ports in arch/powerpc with bootwrapper support that
2171 recalculate the memory size from the SDRAM controller setup
2172 will have to get fixed in Linux additionally.
2174 This option can be used as a workaround for the 440EPx/GRx
2175 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't
2178 WARNING: Please make sure that this value is a multiple of
2179 the Linux page size (normally 4k). If this is not the case,
2180 then the end address of the Linux memory will be located at a
2181 non page size aligned address and this could cause major
2184 - CONFIG_SYS_TFTP_LOADADDR:
2185 Default load address for network file downloads
2187 - CONFIG_SYS_LOADS_BAUD_CHANGE:
2188 Enable temporary baudrate change while serial download
2190 - CONFIG_SYS_SDRAM_BASE:
2191 Physical start address of SDRAM. _Must_ be 0 here.
2193 - CONFIG_SYS_MBIO_BASE:
2194 Physical start address of Motherboard I/O (if using a
2197 - CONFIG_SYS_FLASH_BASE:
2198 Physical start address of Flash memory.
2200 - CONFIG_SYS_MONITOR_BASE:
2201 Physical start address of boot monitor code (set by
2202 make config files to be same as the text base address
2203 (TEXT_BASE) used when linking) - same as
2204 CONFIG_SYS_FLASH_BASE when booting from flash.
2206 - CONFIG_SYS_MONITOR_LEN:
2207 Size of memory reserved for monitor code, used to
2208 determine _at_compile_time_ (!) if the environment is
2209 embedded within the U-Boot image, or in a separate
2212 - CONFIG_SYS_MALLOC_LEN:
2213 Size of DRAM reserved for malloc() use.
2215 - CONFIG_SYS_BOOTM_LEN:
2216 Normally compressed uImages are limited to an
2217 uncompressed size of 8 MBytes. If this is not enough,
2218 you can define CONFIG_SYS_BOOTM_LEN in your board config file
2219 to adjust this setting to your needs.
2221 - CONFIG_SYS_BOOTMAPSZ:
2222 Maximum size of memory mapped by the startup code of
2223 the Linux kernel; all data that must be processed by
2224 the Linux kernel (bd_info, boot arguments, FDT blob if
2225 used) must be put below this limit, unless "bootm_low"
2226 enviroment variable is defined and non-zero. In such case
2227 all data for the Linux kernel must be between "bootm_low"
2228 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ.
2230 - CONFIG_SYS_MAX_FLASH_BANKS:
2231 Max number of Flash memory banks
2233 - CONFIG_SYS_MAX_FLASH_SECT:
2234 Max number of sectors on a Flash chip
2236 - CONFIG_SYS_FLASH_ERASE_TOUT:
2237 Timeout for Flash erase operations (in ms)
2239 - CONFIG_SYS_FLASH_WRITE_TOUT:
2240 Timeout for Flash write operations (in ms)
2242 - CONFIG_SYS_FLASH_LOCK_TOUT
2243 Timeout for Flash set sector lock bit operation (in ms)
2245 - CONFIG_SYS_FLASH_UNLOCK_TOUT
2246 Timeout for Flash clear lock bits operation (in ms)
2248 - CONFIG_SYS_FLASH_PROTECTION
2249 If defined, hardware flash sectors protection is used
2250 instead of U-Boot software protection.
2252 - CONFIG_SYS_DIRECT_FLASH_TFTP:
2254 Enable TFTP transfers directly to flash memory;
2255 without this option such a download has to be
2256 performed in two steps: (1) download to RAM, and (2)
2257 copy from RAM to flash.
2259 The two-step approach is usually more reliable, since
2260 you can check if the download worked before you erase
2261 the flash, but in some situations (when system RAM is
2262 too limited to allow for a temporary copy of the
2263 downloaded image) this option may be very useful.
2265 - CONFIG_SYS_FLASH_CFI:
2266 Define if the flash driver uses extra elements in the
2267 common flash structure for storing flash geometry.
2269 - CONFIG_FLASH_CFI_DRIVER
2270 This option also enables the building of the cfi_flash driver
2271 in the drivers directory
2273 - CONFIG_FLASH_CFI_MTD
2274 This option enables the building of the cfi_mtd driver
2275 in the drivers directory. The driver exports CFI flash
2278 - CONFIG_SYS_FLASH_USE_BUFFER_WRITE
2279 Use buffered writes to flash.
2281 - CONFIG_FLASH_SPANSION_S29WS_N
2282 s29ws-n MirrorBit flash has non-standard addresses for buffered
2285 - CONFIG_SYS_FLASH_QUIET_TEST
2286 If this option is defined, the common CFI flash doesn't
2287 print it's warning upon not recognized FLASH banks. This
2288 is useful, if some of the configured banks are only
2289 optionally available.
2291 - CONFIG_FLASH_SHOW_PROGRESS
2292 If defined (must be an integer), print out countdown
2293 digits and dots. Recommended value: 45 (9..1) for 80
2294 column displays, 15 (3..1) for 40 column displays.
2296 - CONFIG_SYS_RX_ETH_BUFFER:
2297 Defines the number of Ethernet receive buffers. On some
2298 Ethernet controllers it is recommended to set this value
2299 to 8 or even higher (EEPRO100 or 405 EMAC), since all
2300 buffers can be full shortly after enabling the interface
2301 on high Ethernet traffic.
2302 Defaults to 4 if not defined.
2304 The following definitions that deal with the placement and management
2305 of environment data (variable area); in general, we support the
2306 following configurations:
2308 - CONFIG_ENV_IS_IN_FLASH:
2310 Define this if the environment is in flash memory.
2312 a) The environment occupies one whole flash sector, which is
2313 "embedded" in the text segment with the U-Boot code. This
2314 happens usually with "bottom boot sector" or "top boot
2315 sector" type flash chips, which have several smaller
2316 sectors at the start or the end. For instance, such a
2317 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
2318 such a case you would place the environment in one of the
2319 4 kB sectors - with U-Boot code before and after it. With
2320 "top boot sector" type flash chips, you would put the
2321 environment in one of the last sectors, leaving a gap
2322 between U-Boot and the environment.
2324 - CONFIG_ENV_OFFSET:
2326 Offset of environment data (variable area) to the
2327 beginning of flash memory; for instance, with bottom boot
2328 type flash chips the second sector can be used: the offset
2329 for this sector is given here.
2331 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE.
2335 This is just another way to specify the start address of
2336 the flash sector containing the environment (instead of
2339 - CONFIG_ENV_SECT_SIZE:
2341 Size of the sector containing the environment.
2344 b) Sometimes flash chips have few, equal sized, BIG sectors.
2345 In such a case you don't want to spend a whole sector for
2350 If you use this in combination with CONFIG_ENV_IS_IN_FLASH
2351 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part
2352 of this flash sector for the environment. This saves
2353 memory for the RAM copy of the environment.
2355 It may also save flash memory if you decide to use this
2356 when your environment is "embedded" within U-Boot code,
2357 since then the remainder of the flash sector could be used
2358 for U-Boot code. It should be pointed out that this is
2359 STRONGLY DISCOURAGED from a robustness point of view:
2360 updating the environment in flash makes it always
2361 necessary to erase the WHOLE sector. If something goes
2362 wrong before the contents has been restored from a copy in
2363 RAM, your target system will be dead.
2365 - CONFIG_ENV_ADDR_REDUND
2366 CONFIG_ENV_SIZE_REDUND
2368 These settings describe a second storage area used to hold
2369 a redundant copy of the environment data, so that there is
2370 a valid backup copy in case there is a power failure during
2371 a "saveenv" operation.
2373 BE CAREFUL! Any changes to the flash layout, and some changes to the
2374 source code will make it necessary to adapt <board>/u-boot.lds*
2378 - CONFIG_ENV_IS_IN_NVRAM:
2380 Define this if you have some non-volatile memory device
2381 (NVRAM, battery buffered SRAM) which you want to use for the
2387 These two #defines are used to determine the memory area you
2388 want to use for environment. It is assumed that this memory
2389 can just be read and written to, without any special
2392 BE CAREFUL! The first access to the environment happens quite early
2393 in U-Boot initalization (when we try to get the setting of for the
2394 console baudrate). You *MUST* have mapped your NVRAM area then, or
2397 Please note that even with NVRAM we still use a copy of the
2398 environment in RAM: we could work on NVRAM directly, but we want to
2399 keep settings there always unmodified except somebody uses "saveenv"
2400 to save the current settings.
2403 - CONFIG_ENV_IS_IN_EEPROM:
2405 Use this if you have an EEPROM or similar serial access
2406 device and a driver for it.
2408 - CONFIG_ENV_OFFSET:
2411 These two #defines specify the offset and size of the
2412 environment area within the total memory of your EEPROM.
2414 - CONFIG_SYS_I2C_EEPROM_ADDR:
2415 If defined, specified the chip address of the EEPROM device.
2416 The default address is zero.
2418 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS:
2419 If defined, the number of bits used to address bytes in a
2420 single page in the EEPROM device. A 64 byte page, for example
2421 would require six bits.
2423 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS:
2424 If defined, the number of milliseconds to delay between
2425 page writes. The default is zero milliseconds.
2427 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN:
2428 The length in bytes of the EEPROM memory array address. Note
2429 that this is NOT the chip address length!
2431 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW:
2432 EEPROM chips that implement "address overflow" are ones
2433 like Catalyst 24WC04/08/16 which has 9/10/11 bits of
2434 address and the extra bits end up in the "chip address" bit
2435 slots. This makes a 24WC08 (1Kbyte) chip look like four 256
2438 Note that we consider the length of the address field to
2439 still be one byte because the extra address bits are hidden
2440 in the chip address.
2442 - CONFIG_SYS_EEPROM_SIZE:
2443 The size in bytes of the EEPROM device.
2446 - CONFIG_ENV_IS_IN_DATAFLASH:
2448 Define this if you have a DataFlash memory device which you
2449 want to use for the environment.
2451 - CONFIG_ENV_OFFSET:
2455 These three #defines specify the offset and size of the
2456 environment area within the total memory of your DataFlash placed
2457 at the specified address.
2459 - CONFIG_ENV_IS_IN_NAND:
2461 Define this if you have a NAND device which you want to use
2462 for the environment.
2464 - CONFIG_ENV_OFFSET:
2467 These two #defines specify the offset and size of the environment
2468 area within the first NAND device.
2470 - CONFIG_ENV_OFFSET_REDUND
2472 This setting describes a second storage area of CONFIG_ENV_SIZE
2473 size used to hold a redundant copy of the environment data,
2474 so that there is a valid backup copy in case there is a
2475 power failure during a "saveenv" operation.
2477 Note: CONFIG_ENV_OFFSET and CONFIG_ENV_OFFSET_REDUND must be aligned
2478 to a block boundary, and CONFIG_ENV_SIZE must be a multiple of
2479 the NAND devices block size.
2481 - CONFIG_NAND_ENV_DST
2483 Defines address in RAM to which the nand_spl code should copy the
2484 environment. If redundant environment is used, it will be copied to
2485 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE.
2487 - CONFIG_SYS_SPI_INIT_OFFSET
2489 Defines offset to the initial SPI buffer area in DPRAM. The
2490 area is used at an early stage (ROM part) if the environment
2491 is configured to reside in the SPI EEPROM: We need a 520 byte
2492 scratch DPRAM area. It is used between the two initialization
2493 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
2494 to be a good choice since it makes it far enough from the
2495 start of the data area as well as from the stack pointer.
2497 Please note that the environment is read-only until the monitor
2498 has been relocated to RAM and a RAM copy of the environment has been
2499 created; also, when using EEPROM you will have to use getenv_r()
2500 until then to read environment variables.
2502 The environment is protected by a CRC32 checksum. Before the monitor
2503 is relocated into RAM, as a result of a bad CRC you will be working
2504 with the compiled-in default environment - *silently*!!! [This is
2505 necessary, because the first environment variable we need is the
2506 "baudrate" setting for the console - if we have a bad CRC, we don't
2507 have any device yet where we could complain.]
2509 Note: once the monitor has been relocated, then it will complain if
2510 the default environment is used; a new CRC is computed as soon as you
2511 use the "saveenv" command to store a valid environment.
2513 - CONFIG_SYS_FAULT_ECHO_LINK_DOWN:
2514 Echo the inverted Ethernet link state to the fault LED.
2516 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR
2517 also needs to be defined.
2519 - CONFIG_SYS_FAULT_MII_ADDR:
2520 MII address of the PHY to check for the Ethernet link state.
2522 - CONFIG_SYS_64BIT_VSPRINTF:
2523 Makes vsprintf (and all *printf functions) support printing
2524 of 64bit values by using the L quantifier
2526 - CONFIG_SYS_64BIT_STRTOUL:
2527 Adds simple_strtoull that returns a 64bit value
2529 - CONFIG_NS16550_MIN_FUNCTIONS:
2530 Define this if you desire to only have use of the NS16550_init
2531 and NS16550_putc functions for the serial driver located at
2532 drivers/serial/ns16550.c. This option is useful for saving
2533 space for already greatly restricted images, including but not
2534 limited to NAND_SPL configurations.
2536 Low Level (hardware related) configuration options:
2537 ---------------------------------------------------
2539 - CONFIG_SYS_CACHELINE_SIZE:
2540 Cache Line Size of the CPU.
2542 - CONFIG_SYS_DEFAULT_IMMR:
2543 Default address of the IMMR after system reset.
2545 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
2546 and RPXsuper) to be able to adjust the position of
2547 the IMMR register after a reset.
2549 - Floppy Disk Support:
2550 CONFIG_SYS_FDC_DRIVE_NUMBER
2552 the default drive number (default value 0)
2554 CONFIG_SYS_ISA_IO_STRIDE
2556 defines the spacing between FDC chipset registers
2559 CONFIG_SYS_ISA_IO_OFFSET
2561 defines the offset of register from address. It
2562 depends on which part of the data bus is connected to
2563 the FDC chipset. (default value 0)
2565 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and
2566 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their
2569 if CONFIG_SYS_FDC_HW_INIT is defined, then the function
2570 fdc_hw_init() is called at the beginning of the FDC
2571 setup. fdc_hw_init() must be provided by the board
2572 source code. It is used to make hardware dependant
2575 - CONFIG_SYS_IMMR: Physical address of the Internal Memory.
2576 DO NOT CHANGE unless you know exactly what you're
2577 doing! (11-4) [MPC8xx/82xx systems only]
2579 - CONFIG_SYS_INIT_RAM_ADDR:
2581 Start address of memory area that can be used for
2582 initial data and stack; please note that this must be
2583 writable memory that is working WITHOUT special
2584 initialization, i. e. you CANNOT use normal RAM which
2585 will become available only after programming the
2586 memory controller and running certain initialization
2589 U-Boot uses the following memory types:
2590 - MPC8xx and MPC8260: IMMR (internal memory of the CPU)
2591 - MPC824X: data cache
2592 - PPC4xx: data cache
2594 - CONFIG_SYS_GBL_DATA_OFFSET:
2596 Offset of the initial data structure in the memory
2597 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually
2598 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial
2599 data is located at the end of the available space
2600 (sometimes written as (CONFIG_SYS_INIT_RAM_END -
2601 CONFIG_SYS_INIT_DATA_SIZE), and the initial stack is just
2602 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR +
2603 CONFIG_SYS_GBL_DATA_OFFSET) downward.
2606 On the MPC824X (or other systems that use the data
2607 cache for initial memory) the address chosen for
2608 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must
2609 point to an otherwise UNUSED address space between
2610 the top of RAM and the start of the PCI space.
2612 - CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6)
2614 - CONFIG_SYS_SYPCR: System Protection Control (11-9)
2616 - CONFIG_SYS_TBSCR: Time Base Status and Control (11-26)
2618 - CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31)
2620 - CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30)
2622 - CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27)
2624 - CONFIG_SYS_OR_TIMING_SDRAM:
2627 - CONFIG_SYS_MAMR_PTA:
2628 periodic timer for refresh
2630 - CONFIG_SYS_DER: Debug Event Register (37-47)
2632 - FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM,
2633 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP,
2634 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM,
2635 CONFIG_SYS_BR1_PRELIM:
2636 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
2638 - SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
2639 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM,
2640 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM:
2641 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
2643 - CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K,
2644 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL:
2645 Machine Mode Register and Memory Periodic Timer
2646 Prescaler definitions (SDRAM timing)
2648 - CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]:
2649 enable I2C microcode relocation patch (MPC8xx);
2650 define relocation offset in DPRAM [DSP2]
2652 - CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]:
2653 enable SMC microcode relocation patch (MPC8xx);
2654 define relocation offset in DPRAM [SMC1]
2656 - CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]:
2657 enable SPI microcode relocation patch (MPC8xx);
2658 define relocation offset in DPRAM [SCC4]
2660 - CONFIG_SYS_USE_OSCCLK:
2661 Use OSCM clock mode on MBX8xx board. Be careful,
2662 wrong setting might damage your board. Read
2663 doc/README.MBX before setting this variable!
2665 - CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
2666 Offset of the bootmode word in DPRAM used by post
2667 (Power On Self Tests). This definition overrides
2668 #define'd default value in commproc.h resp.
2671 - CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB,
2672 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL,
2673 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS,
2674 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB,
2675 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
2676 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL,
2677 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE,
2678 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only)
2679 Overrides the default PCI memory map in cpu/mpc8260/pci.c if set.
2681 - CONFIG_PCI_DISABLE_PCIE:
2682 Disable PCI-Express on systems where it is supported but not
2686 Get DDR timing information from an I2C EEPROM. Common
2687 with pluggable memory modules such as SODIMMs
2690 I2C address of the SPD EEPROM
2692 - CONFIG_SYS_SPD_BUS_NUM
2693 If SPD EEPROM is on an I2C bus other than the first
2694 one, specify here. Note that the value must resolve
2695 to something your driver can deal with.
2697 - CONFIG_SYS_83XX_DDR_USES_CS0
2698 Only for 83xx systems. If specified, then DDR should
2699 be configured using CS0 and CS1 instead of CS2 and CS3.
2701 - CONFIG_ETHER_ON_FEC[12]
2702 Define to enable FEC[12] on a 8xx series processor.
2704 - CONFIG_FEC[12]_PHY
2705 Define to the hardcoded PHY address which corresponds
2706 to the given FEC; i. e.
2707 #define CONFIG_FEC1_PHY 4
2708 means that the PHY with address 4 is connected to FEC1
2710 When set to -1, means to probe for first available.
2712 - CONFIG_FEC[12]_PHY_NORXERR
2713 The PHY does not have a RXERR line (RMII only).
2714 (so program the FEC to ignore it).
2717 Enable RMII mode for all FECs.
2718 Note that this is a global option, we can't
2719 have one FEC in standard MII mode and another in RMII mode.
2721 - CONFIG_CRC32_VERIFY
2722 Add a verify option to the crc32 command.
2725 => crc32 -v <address> <count> <crc32>
2727 Where address/count indicate a memory area
2728 and crc32 is the correct crc32 which the
2732 Add the "loopw" memory command. This only takes effect if
2733 the memory commands are activated globally (CONFIG_CMD_MEM).
2736 Add the "mdc" and "mwc" memory commands. These are cyclic
2741 This command will print 4 bytes (10,11,12,13) each 500 ms.
2743 => mwc.l 100 12345678 10
2744 This command will write 12345678 to address 100 all 10 ms.
2746 This only takes effect if the memory commands are activated
2747 globally (CONFIG_CMD_MEM).
2749 - CONFIG_SKIP_LOWLEVEL_INIT
2750 - CONFIG_SKIP_RELOCATE_UBOOT
2752 [ARM only] If these variables are defined, then
2753 certain low level initializations (like setting up
2754 the memory controller) are omitted and/or U-Boot does
2755 not relocate itself into RAM.
2756 Normally these variables MUST NOT be defined. The
2757 only exception is when U-Boot is loaded (to RAM) by
2758 some other boot loader or by a debugger which
2759 performs these initializations itself.
2763 Modifies the behaviour of start.S when compiling a loader
2764 that is executed before the actual U-Boot. E.g. when
2765 compiling a NAND SPL.
2767 Building the Software:
2768 ======================
2770 Building U-Boot has been tested in several native build environments
2771 and in many different cross environments. Of course we cannot support
2772 all possibly existing versions of cross development tools in all
2773 (potentially obsolete) versions. In case of tool chain problems we
2774 recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK)
2775 which is extensively used to build and test U-Boot.
2777 If you are not using a native environment, it is assumed that you
2778 have GNU cross compiling tools available in your path. In this case,
2779 you must set the environment variable CROSS_COMPILE in your shell.
2780 Note that no changes to the Makefile or any other source files are
2781 necessary. For example using the ELDK on a 4xx CPU, please enter:
2783 $ CROSS_COMPILE=ppc_4xx-
2784 $ export CROSS_COMPILE
2786 Note: If you wish to generate Windows versions of the utilities in
2787 the tools directory you can use the MinGW toolchain
2788 (http://www.mingw.org). Set your HOST tools to the MinGW
2789 toolchain and execute 'make tools'. For example:
2791 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools
2793 Binaries such as tools/mkimage.exe will be created which can
2794 be executed on computers running Windows.
2796 U-Boot is intended to be simple to build. After installing the
2797 sources you must configure U-Boot for one specific board type. This
2802 where "NAME_config" is the name of one of the existing configu-
2803 rations; see the main Makefile for supported names.
2805 Note: for some board special configuration names may exist; check if
2806 additional information is available from the board vendor; for
2807 instance, the TQM823L systems are available without (standard)
2808 or with LCD support. You can select such additional "features"
2809 when choosing the configuration, i. e.
2812 - will configure for a plain TQM823L, i. e. no LCD support
2814 make TQM823L_LCD_config
2815 - will configure for a TQM823L with U-Boot console on LCD
2820 Finally, type "make all", and you should get some working U-Boot
2821 images ready for download to / installation on your system:
2823 - "u-boot.bin" is a raw binary image
2824 - "u-boot" is an image in ELF binary format
2825 - "u-boot.srec" is in Motorola S-Record format
2827 By default the build is performed locally and the objects are saved
2828 in the source directory. One of the two methods can be used to change
2829 this behavior and build U-Boot to some external directory:
2831 1. Add O= to the make command line invocations:
2833 make O=/tmp/build distclean
2834 make O=/tmp/build NAME_config
2835 make O=/tmp/build all
2837 2. Set environment variable BUILD_DIR to point to the desired location:
2839 export BUILD_DIR=/tmp/build
2844 Note that the command line "O=" setting overrides the BUILD_DIR environment
2848 Please be aware that the Makefiles assume you are using GNU make, so
2849 for instance on NetBSD you might need to use "gmake" instead of
2853 If the system board that you have is not listed, then you will need
2854 to port U-Boot to your hardware platform. To do this, follow these
2857 1. Add a new configuration option for your board to the toplevel
2858 "Makefile" and to the "MAKEALL" script, using the existing
2859 entries as examples. Note that here and at many other places
2860 boards and other names are listed in alphabetical sort order. Please
2862 2. Create a new directory to hold your board specific code. Add any
2863 files you need. In your board directory, you will need at least
2864 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
2865 3. Create a new configuration file "include/configs/<board>.h" for
2867 3. If you're porting U-Boot to a new CPU, then also create a new
2868 directory to hold your CPU specific code. Add any files you need.
2869 4. Run "make <board>_config" with your new name.
2870 5. Type "make", and you should get a working "u-boot.srec" file
2871 to be installed on your target system.
2872 6. Debug and solve any problems that might arise.
2873 [Of course, this last step is much harder than it sounds.]
2876 Testing of U-Boot Modifications, Ports to New Hardware, etc.:
2877 ==============================================================
2879 If you have modified U-Boot sources (for instance added a new board
2880 or support for new devices, a new CPU, etc.) you are expected to
2881 provide feedback to the other developers. The feedback normally takes
2882 the form of a "patch", i. e. a context diff against a certain (latest
2883 official or latest in the git repository) version of U-Boot sources.
2885 But before you submit such a patch, please verify that your modifi-
2886 cation did not break existing code. At least make sure that *ALL* of
2887 the supported boards compile WITHOUT ANY compiler warnings. To do so,
2888 just run the "MAKEALL" script, which will configure and build U-Boot
2889 for ALL supported system. Be warned, this will take a while. You can
2890 select which (cross) compiler to use by passing a `CROSS_COMPILE'
2891 environment variable to the script, i. e. to use the ELDK cross tools
2894 CROSS_COMPILE=ppc_8xx- MAKEALL
2896 or to build on a native PowerPC system you can type
2898 CROSS_COMPILE=' ' MAKEALL
2900 When using the MAKEALL script, the default behaviour is to build
2901 U-Boot in the source directory. This location can be changed by
2902 setting the BUILD_DIR environment variable. Also, for each target
2903 built, the MAKEALL script saves two log files (<target>.ERR and
2904 <target>.MAKEALL) in the <source dir>/LOG directory. This default
2905 location can be changed by setting the MAKEALL_LOGDIR environment
2906 variable. For example:
2908 export BUILD_DIR=/tmp/build
2909 export MAKEALL_LOGDIR=/tmp/log
2910 CROSS_COMPILE=ppc_8xx- MAKEALL
2912 With the above settings build objects are saved in the /tmp/build,
2913 log files are saved in the /tmp/log and the source tree remains clean
2914 during the whole build process.
2917 See also "U-Boot Porting Guide" below.
2920 Monitor Commands - Overview:
2921 ============================
2923 go - start application at address 'addr'
2924 run - run commands in an environment variable
2925 bootm - boot application image from memory
2926 bootp - boot image via network using BootP/TFTP protocol
2927 tftpboot- boot image via network using TFTP protocol
2928 and env variables "ipaddr" and "serverip"
2929 (and eventually "gatewayip")
2930 rarpboot- boot image via network using RARP/TFTP protocol
2931 diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
2932 loads - load S-Record file over serial line
2933 loadb - load binary file over serial line (kermit mode)
2935 mm - memory modify (auto-incrementing)
2936 nm - memory modify (constant address)
2937 mw - memory write (fill)
2939 cmp - memory compare
2940 crc32 - checksum calculation
2941 i2c - I2C sub-system
2942 sspi - SPI utility commands
2943 base - print or set address offset
2944 printenv- print environment variables
2945 setenv - set environment variables
2946 saveenv - save environment variables to persistent storage
2947 protect - enable or disable FLASH write protection
2948 erase - erase FLASH memory
2949 flinfo - print FLASH memory information
2950 bdinfo - print Board Info structure
2951 iminfo - print header information for application image
2952 coninfo - print console devices and informations
2953 ide - IDE sub-system
2954 loop - infinite loop on address range
2955 loopw - infinite write loop on address range
2956 mtest - simple RAM test
2957 icache - enable or disable instruction cache
2958 dcache - enable or disable data cache
2959 reset - Perform RESET of the CPU
2960 echo - echo args to console
2961 version - print monitor version
2962 help - print online help
2963 ? - alias for 'help'
2966 Monitor Commands - Detailed Description:
2967 ========================================
2971 For now: just type "help <command>".
2974 Environment Variables:
2975 ======================
2977 U-Boot supports user configuration using Environment Variables which
2978 can be made persistent by saving to Flash memory.
2980 Environment Variables are set using "setenv", printed using
2981 "printenv", and saved to Flash using "saveenv". Using "setenv"
2982 without a value can be used to delete a variable from the
2983 environment. As long as you don't save the environment you are
2984 working with an in-memory copy. In case the Flash area containing the
2985 environment is erased by accident, a default environment is provided.
2987 Some configuration options can be set using Environment Variables:
2989 baudrate - see CONFIG_BAUDRATE
2991 bootdelay - see CONFIG_BOOTDELAY
2993 bootcmd - see CONFIG_BOOTCOMMAND
2995 bootargs - Boot arguments when booting an RTOS image
2997 bootfile - Name of the image to load with TFTP
2999 bootm_low - Memory range available for image processing in the bootm
3000 command can be restricted. This variable is given as
3001 a hexadecimal number and defines lowest address allowed
3002 for use by the bootm command. See also "bootm_size"
3003 environment variable. Address defined by "bootm_low" is
3004 also the base of the initial memory mapping for the Linux
3005 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ.
3007 bootm_size - Memory range available for image processing in the bootm
3008 command can be restricted. This variable is given as
3009 a hexadecimal number and defines the size of the region
3010 allowed for use by the bootm command. See also "bootm_low"
3011 environment variable.
3013 updatefile - Location of the software update file on a TFTP server, used
3014 by the automatic software update feature. Please refer to
3015 documentation in doc/README.update for more details.
3017 autoload - if set to "no" (any string beginning with 'n'),
3018 "bootp" will just load perform a lookup of the
3019 configuration from the BOOTP server, but not try to
3020 load any image using TFTP
3022 autostart - if set to "yes", an image loaded using the "bootp",
3023 "rarpboot", "tftpboot" or "diskboot" commands will
3024 be automatically started (by internally calling
3027 If set to "no", a standalone image passed to the
3028 "bootm" command will be copied to the load address
3029 (and eventually uncompressed), but NOT be started.
3030 This can be used to load and uncompress arbitrary
3033 i2cfast - (PPC405GP|PPC405EP only)
3034 if set to 'y' configures Linux I2C driver for fast
3035 mode (400kHZ). This environment variable is used in
3036 initialization code. So, for changes to be effective
3037 it must be saved and board must be reset.
3039 initrd_high - restrict positioning of initrd images:
3040 If this variable is not set, initrd images will be
3041 copied to the highest possible address in RAM; this
3042 is usually what you want since it allows for
3043 maximum initrd size. If for some reason you want to
3044 make sure that the initrd image is loaded below the
3045 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment
3046 variable to a value of "no" or "off" or "0".
3047 Alternatively, you can set it to a maximum upper
3048 address to use (U-Boot will still check that it
3049 does not overwrite the U-Boot stack and data).
3051 For instance, when you have a system with 16 MB
3052 RAM, and want to reserve 4 MB from use by Linux,
3053 you can do this by adding "mem=12M" to the value of
3054 the "bootargs" variable. However, now you must make
3055 sure that the initrd image is placed in the first
3056 12 MB as well - this can be done with
3058 setenv initrd_high 00c00000
3060 If you set initrd_high to 0xFFFFFFFF, this is an
3061 indication to U-Boot that all addresses are legal
3062 for the Linux kernel, including addresses in flash
3063 memory. In this case U-Boot will NOT COPY the
3064 ramdisk at all. This may be useful to reduce the
3065 boot time on your system, but requires that this
3066 feature is supported by your Linux kernel.
3068 ipaddr - IP address; needed for tftpboot command
3070 loadaddr - Default load address for commands like "bootp",
3071 "rarpboot", "tftpboot", "loadb" or "diskboot"
3073 loads_echo - see CONFIG_LOADS_ECHO
3075 serverip - TFTP server IP address; needed for tftpboot command
3077 bootretry - see CONFIG_BOOT_RETRY_TIME
3079 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
3081 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
3083 ethprime - When CONFIG_NET_MULTI is enabled controls which
3084 interface is used first.
3086 ethact - When CONFIG_NET_MULTI is enabled controls which
3087 interface is currently active. For example you
3088 can do the following
3090 => setenv ethact FEC ETHERNET
3091 => ping 192.168.0.1 # traffic sent on FEC ETHERNET
3092 => setenv ethact SCC ETHERNET
3093 => ping 10.0.0.1 # traffic sent on SCC ETHERNET
3095 ethrotate - When set to "no" U-Boot does not go through all
3096 available network interfaces.
3097 It just stays at the currently selected interface.
3099 netretry - When set to "no" each network operation will
3100 either succeed or fail without retrying.
3101 When set to "once" the network operation will
3102 fail when all the available network interfaces
3103 are tried once without success.
3104 Useful on scripts which control the retry operation
3107 npe_ucode - set load address for the NPE microcode
3109 tftpsrcport - If this is set, the value is used for TFTP's
3112 tftpdstport - If this is set, the value is used for TFTP's UDP
3113 destination port instead of the Well Know Port 69.
3115 vlan - When set to a value < 4095 the traffic over
3116 Ethernet is encapsulated/received over 802.1q
3119 The following environment variables may be used and automatically
3120 updated by the network boot commands ("bootp" and "rarpboot"),
3121 depending the information provided by your boot server:
3123 bootfile - see above
3124 dnsip - IP address of your Domain Name Server
3125 dnsip2 - IP address of your secondary Domain Name Server
3126 gatewayip - IP address of the Gateway (Router) to use
3127 hostname - Target hostname
3129 netmask - Subnet Mask
3130 rootpath - Pathname of the root filesystem on the NFS server
3131 serverip - see above
3134 There are two special Environment Variables:
3136 serial# - contains hardware identification information such
3137 as type string and/or serial number
3138 ethaddr - Ethernet address
3140 These variables can be set only once (usually during manufacturing of
3141 the board). U-Boot refuses to delete or overwrite these variables
3142 once they have been set once.
3145 Further special Environment Variables:
3147 ver - Contains the U-Boot version string as printed
3148 with the "version" command. This variable is
3149 readonly (see CONFIG_VERSION_VARIABLE).
3152 Please note that changes to some configuration parameters may take
3153 only effect after the next boot (yes, that's just like Windoze :-).
3156 Command Line Parsing:
3157 =====================
3159 There are two different command line parsers available with U-Boot:
3160 the old "simple" one, and the much more powerful "hush" shell:
3162 Old, simple command line parser:
3163 --------------------------------
3165 - supports environment variables (through setenv / saveenv commands)
3166 - several commands on one line, separated by ';'
3167 - variable substitution using "... ${name} ..." syntax
3168 - special characters ('$', ';') can be escaped by prefixing with '\',
3170 setenv bootcmd bootm \${address}
3171 - You can also escape text by enclosing in single apostrophes, for example:
3172 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
3177 - similar to Bourne shell, with control structures like
3178 if...then...else...fi, for...do...done; while...do...done,
3179 until...do...done, ...
3180 - supports environment ("global") variables (through setenv / saveenv
3181 commands) and local shell variables (through standard shell syntax
3182 "name=value"); only environment variables can be used with "run"
3188 (1) If a command line (or an environment variable executed by a "run"
3189 command) contains several commands separated by semicolon, and
3190 one of these commands fails, then the remaining commands will be
3193 (2) If you execute several variables with one call to run (i. e.
3194 calling run with a list of variables as arguments), any failing
3195 command will cause "run" to terminate, i. e. the remaining
3196 variables are not executed.
3198 Note for Redundant Ethernet Interfaces:
3199 =======================================
3201 Some boards come with redundant Ethernet interfaces; U-Boot supports
3202 such configurations and is capable of automatic selection of a
3203 "working" interface when needed. MAC assignment works as follows:
3205 Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
3206 MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
3207 "eth1addr" (=>eth1), "eth2addr", ...
3209 If the network interface stores some valid MAC address (for instance
3210 in SROM), this is used as default address if there is NO correspon-
3211 ding setting in the environment; if the corresponding environment
3212 variable is set, this overrides the settings in the card; that means:
3214 o If the SROM has a valid MAC address, and there is no address in the
3215 environment, the SROM's address is used.
3217 o If there is no valid address in the SROM, and a definition in the
3218 environment exists, then the value from the environment variable is
3221 o If both the SROM and the environment contain a MAC address, and
3222 both addresses are the same, this MAC address is used.
3224 o If both the SROM and the environment contain a MAC address, and the
3225 addresses differ, the value from the environment is used and a
3228 o If neither SROM nor the environment contain a MAC address, an error
3235 U-Boot is capable of booting (and performing other auxiliary operations on)
3236 images in two formats:
3238 New uImage format (FIT)
3239 -----------------------
3241 Flexible and powerful format based on Flattened Image Tree -- FIT (similar
3242 to Flattened Device Tree). It allows the use of images with multiple
3243 components (several kernels, ramdisks, etc.), with contents protected by
3244 SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
3250 Old image format is based on binary files which can be basically anything,
3251 preceded by a special header; see the definitions in include/image.h for
3252 details; basically, the header defines the following image properties:
3254 * Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
3255 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
3256 LynxOS, pSOS, QNX, RTEMS, INTEGRITY;
3257 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS,
3259 * Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86,
3260 IA64, MIPS, NIOS, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
3261 Currently supported: ARM, AVR32, Intel x86, MIPS, NIOS, PowerPC).
3262 * Compression Type (uncompressed, gzip, bzip2)
3268 The header is marked by a special Magic Number, and both the header
3269 and the data portions of the image are secured against corruption by
3276 Although U-Boot should support any OS or standalone application
3277 easily, the main focus has always been on Linux during the design of
3280 U-Boot includes many features that so far have been part of some
3281 special "boot loader" code within the Linux kernel. Also, any
3282 "initrd" images to be used are no longer part of one big Linux image;
3283 instead, kernel and "initrd" are separate images. This implementation
3284 serves several purposes:
3286 - the same features can be used for other OS or standalone
3287 applications (for instance: using compressed images to reduce the
3288 Flash memory footprint)
3290 - it becomes much easier to port new Linux kernel versions because
3291 lots of low-level, hardware dependent stuff are done by U-Boot
3293 - the same Linux kernel image can now be used with different "initrd"
3294 images; of course this also means that different kernel images can
3295 be run with the same "initrd". This makes testing easier (you don't
3296 have to build a new "zImage.initrd" Linux image when you just
3297 change a file in your "initrd"). Also, a field-upgrade of the
3298 software is easier now.
3304 Porting Linux to U-Boot based systems:
3305 ---------------------------------------
3307 U-Boot cannot save you from doing all the necessary modifications to
3308 configure the Linux device drivers for use with your target hardware
3309 (no, we don't intend to provide a full virtual machine interface to
3312 But now you can ignore ALL boot loader code (in arch/ppc/mbxboot).
3314 Just make sure your machine specific header file (for instance
3315 include/asm-ppc/tqm8xx.h) includes the same definition of the Board
3316 Information structure as we define in include/asm-<arch>/u-boot.h,
3317 and make sure that your definition of IMAP_ADDR uses the same value
3318 as your U-Boot configuration in CONFIG_SYS_IMMR.
3321 Configuring the Linux kernel:
3322 -----------------------------
3324 No specific requirements for U-Boot. Make sure you have some root
3325 device (initial ramdisk, NFS) for your target system.
3328 Building a Linux Image:
3329 -----------------------
3331 With U-Boot, "normal" build targets like "zImage" or "bzImage" are
3332 not used. If you use recent kernel source, a new build target
3333 "uImage" will exist which automatically builds an image usable by
3334 U-Boot. Most older kernels also have support for a "pImage" target,
3335 which was introduced for our predecessor project PPCBoot and uses a
3336 100% compatible format.
3345 The "uImage" build target uses a special tool (in 'tools/mkimage') to
3346 encapsulate a compressed Linux kernel image with header information,
3347 CRC32 checksum etc. for use with U-Boot. This is what we are doing:
3349 * build a standard "vmlinux" kernel image (in ELF binary format):
3351 * convert the kernel into a raw binary image:
3353 ${CROSS_COMPILE}-objcopy -O binary \
3354 -R .note -R .comment \
3355 -S vmlinux linux.bin
3357 * compress the binary image:
3361 * package compressed binary image for U-Boot:
3363 mkimage -A ppc -O linux -T kernel -C gzip \
3364 -a 0 -e 0 -n "Linux Kernel Image" \
3365 -d linux.bin.gz uImage
3368 The "mkimage" tool can also be used to create ramdisk images for use
3369 with U-Boot, either separated from the Linux kernel image, or
3370 combined into one file. "mkimage" encapsulates the images with a 64
3371 byte header containing information about target architecture,
3372 operating system, image type, compression method, entry points, time
3373 stamp, CRC32 checksums, etc.
3375 "mkimage" can be called in two ways: to verify existing images and
3376 print the header information, or to build new images.
3378 In the first form (with "-l" option) mkimage lists the information
3379 contained in the header of an existing U-Boot image; this includes
3380 checksum verification:
3382 tools/mkimage -l image
3383 -l ==> list image header information
3385 The second form (with "-d" option) is used to build a U-Boot image
3386 from a "data file" which is used as image payload:
3388 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
3389 -n name -d data_file image
3390 -A ==> set architecture to 'arch'
3391 -O ==> set operating system to 'os'
3392 -T ==> set image type to 'type'
3393 -C ==> set compression type 'comp'
3394 -a ==> set load address to 'addr' (hex)
3395 -e ==> set entry point to 'ep' (hex)
3396 -n ==> set image name to 'name'
3397 -d ==> use image data from 'datafile'
3399 Right now, all Linux kernels for PowerPC systems use the same load
3400 address (0x00000000), but the entry point address depends on the
3403 - 2.2.x kernels have the entry point at 0x0000000C,
3404 - 2.3.x and later kernels have the entry point at 0x00000000.
3406 So a typical call to build a U-Boot image would read:
3408 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
3409 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
3410 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz \
3411 > examples/uImage.TQM850L
3412 Image Name: 2.4.4 kernel for TQM850L
3413 Created: Wed Jul 19 02:34:59 2000
3414 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3415 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
3416 Load Address: 0x00000000
3417 Entry Point: 0x00000000
3419 To verify the contents of the image (or check for corruption):
3421 -> tools/mkimage -l examples/uImage.TQM850L
3422 Image Name: 2.4.4 kernel for TQM850L
3423 Created: Wed Jul 19 02:34:59 2000
3424 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3425 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
3426 Load Address: 0x00000000
3427 Entry Point: 0x00000000
3429 NOTE: for embedded systems where boot time is critical you can trade
3430 speed for memory and install an UNCOMPRESSED image instead: this
3431 needs more space in Flash, but boots much faster since it does not
3432 need to be uncompressed:
3434 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz
3435 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
3436 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
3437 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux \
3438 > examples/uImage.TQM850L-uncompressed
3439 Image Name: 2.4.4 kernel for TQM850L
3440 Created: Wed Jul 19 02:34:59 2000
3441 Image Type: PowerPC Linux Kernel Image (uncompressed)
3442 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
3443 Load Address: 0x00000000
3444 Entry Point: 0x00000000
3447 Similar you can build U-Boot images from a 'ramdisk.image.gz' file
3448 when your kernel is intended to use an initial ramdisk:
3450 -> tools/mkimage -n 'Simple Ramdisk Image' \
3451 > -A ppc -O linux -T ramdisk -C gzip \
3452 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
3453 Image Name: Simple Ramdisk Image
3454 Created: Wed Jan 12 14:01:50 2000
3455 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
3456 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
3457 Load Address: 0x00000000
3458 Entry Point: 0x00000000
3461 Installing a Linux Image:
3462 -------------------------
3464 To downloading a U-Boot image over the serial (console) interface,
3465 you must convert the image to S-Record format:
3467 objcopy -I binary -O srec examples/image examples/image.srec
3469 The 'objcopy' does not understand the information in the U-Boot
3470 image header, so the resulting S-Record file will be relative to
3471 address 0x00000000. To load it to a given address, you need to
3472 specify the target address as 'offset' parameter with the 'loads'
3475 Example: install the image to address 0x40100000 (which on the
3476 TQM8xxL is in the first Flash bank):
3478 => erase 40100000 401FFFFF
3484 ## Ready for S-Record download ...
3485 ~>examples/image.srec
3486 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
3488 15989 15990 15991 15992
3489 [file transfer complete]
3491 ## Start Addr = 0x00000000
3494 You can check the success of the download using the 'iminfo' command;
3495 this includes a checksum verification so you can be sure no data
3496 corruption happened:
3500 ## Checking Image at 40100000 ...
3501 Image Name: 2.2.13 for initrd on TQM850L
3502 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3503 Data Size: 335725 Bytes = 327 kB = 0 MB
3504 Load Address: 00000000
3505 Entry Point: 0000000c
3506 Verifying Checksum ... OK
3512 The "bootm" command is used to boot an application that is stored in
3513 memory (RAM or Flash). In case of a Linux kernel image, the contents
3514 of the "bootargs" environment variable is passed to the kernel as
3515 parameters. You can check and modify this variable using the
3516 "printenv" and "setenv" commands:
3519 => printenv bootargs
3520 bootargs=root=/dev/ram
3522 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
3524 => printenv bootargs
3525 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
3528 ## Booting Linux kernel at 40020000 ...
3529 Image Name: 2.2.13 for NFS on TQM850L
3530 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3531 Data Size: 381681 Bytes = 372 kB = 0 MB
3532 Load Address: 00000000
3533 Entry Point: 0000000c
3534 Verifying Checksum ... OK
3535 Uncompressing Kernel Image ... OK
3536 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
3537 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
3538 time_init: decrementer frequency = 187500000/60
3539 Calibrating delay loop... 49.77 BogoMIPS
3540 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
3543 If you want to boot a Linux kernel with initial RAM disk, you pass
3544 the memory addresses of both the kernel and the initrd image (PPBCOOT
3545 format!) to the "bootm" command:
3547 => imi 40100000 40200000
3549 ## Checking Image at 40100000 ...
3550 Image Name: 2.2.13 for initrd on TQM850L
3551 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3552 Data Size: 335725 Bytes = 327 kB = 0 MB
3553 Load Address: 00000000
3554 Entry Point: 0000000c
3555 Verifying Checksum ... OK
3557 ## Checking Image at 40200000 ...
3558 Image Name: Simple Ramdisk Image
3559 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
3560 Data Size: 566530 Bytes = 553 kB = 0 MB
3561 Load Address: 00000000
3562 Entry Point: 00000000
3563 Verifying Checksum ... OK
3565 => bootm 40100000 40200000
3566 ## Booting Linux kernel at 40100000 ...
3567 Image Name: 2.2.13 for initrd on TQM850L
3568 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3569 Data Size: 335725 Bytes = 327 kB = 0 MB
3570 Load Address: 00000000
3571 Entry Point: 0000000c
3572 Verifying Checksum ... OK
3573 Uncompressing Kernel Image ... OK
3574 ## Loading RAMDisk Image at 40200000 ...
3575 Image Name: Simple Ramdisk Image
3576 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
3577 Data Size: 566530 Bytes = 553 kB = 0 MB
3578 Load Address: 00000000
3579 Entry Point: 00000000
3580 Verifying Checksum ... OK
3581 Loading Ramdisk ... OK
3582 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
3583 Boot arguments: root=/dev/ram
3584 time_init: decrementer frequency = 187500000/60
3585 Calibrating delay loop... 49.77 BogoMIPS
3587 RAMDISK: Compressed image found at block 0
3588 VFS: Mounted root (ext2 filesystem).
3592 Boot Linux and pass a flat device tree:
3595 First, U-Boot must be compiled with the appropriate defines. See the section
3596 titled "Linux Kernel Interface" above for a more in depth explanation. The
3597 following is an example of how to start a kernel and pass an updated
3603 oft=oftrees/mpc8540ads.dtb
3604 => tftp $oftaddr $oft
3605 Speed: 1000, full duplex
3607 TFTP from server 192.168.1.1; our IP address is 192.168.1.101
3608 Filename 'oftrees/mpc8540ads.dtb'.
3609 Load address: 0x300000
3612 Bytes transferred = 4106 (100a hex)
3613 => tftp $loadaddr $bootfile
3614 Speed: 1000, full duplex
3616 TFTP from server 192.168.1.1; our IP address is 192.168.1.2
3618 Load address: 0x200000
3619 Loading:############
3621 Bytes transferred = 1029407 (fb51f hex)
3626 => bootm $loadaddr - $oftaddr
3627 ## Booting image at 00200000 ...
3628 Image Name: Linux-2.6.17-dirty
3629 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3630 Data Size: 1029343 Bytes = 1005.2 kB
3631 Load Address: 00000000
3632 Entry Point: 00000000
3633 Verifying Checksum ... OK
3634 Uncompressing Kernel Image ... OK
3635 Booting using flat device tree at 0x300000
3636 Using MPC85xx ADS machine description
3637 Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb
3641 More About U-Boot Image Types:
3642 ------------------------------
3644 U-Boot supports the following image types:
3646 "Standalone Programs" are directly runnable in the environment
3647 provided by U-Boot; it is expected that (if they behave
3648 well) you can continue to work in U-Boot after return from
3649 the Standalone Program.
3650 "OS Kernel Images" are usually images of some Embedded OS which
3651 will take over control completely. Usually these programs
3652 will install their own set of exception handlers, device
3653 drivers, set up the MMU, etc. - this means, that you cannot
3654 expect to re-enter U-Boot except by resetting the CPU.
3655 "RAMDisk Images" are more or less just data blocks, and their
3656 parameters (address, size) are passed to an OS kernel that is
3658 "Multi-File Images" contain several images, typically an OS
3659 (Linux) kernel image and one or more data images like
3660 RAMDisks. This construct is useful for instance when you want
3661 to boot over the network using BOOTP etc., where the boot
3662 server provides just a single image file, but you want to get
3663 for instance an OS kernel and a RAMDisk image.
3665 "Multi-File Images" start with a list of image sizes, each
3666 image size (in bytes) specified by an "uint32_t" in network
3667 byte order. This list is terminated by an "(uint32_t)0".
3668 Immediately after the terminating 0 follow the images, one by
3669 one, all aligned on "uint32_t" boundaries (size rounded up to
3670 a multiple of 4 bytes).
3672 "Firmware Images" are binary images containing firmware (like
3673 U-Boot or FPGA images) which usually will be programmed to
3676 "Script files" are command sequences that will be executed by
3677 U-Boot's command interpreter; this feature is especially
3678 useful when you configure U-Boot to use a real shell (hush)
3679 as command interpreter.
3685 One of the features of U-Boot is that you can dynamically load and
3686 run "standalone" applications, which can use some resources of
3687 U-Boot like console I/O functions or interrupt services.
3689 Two simple examples are included with the sources:
3694 'examples/hello_world.c' contains a small "Hello World" Demo
3695 application; it is automatically compiled when you build U-Boot.
3696 It's configured to run at address 0x00040004, so you can play with it
3700 ## Ready for S-Record download ...
3701 ~>examples/hello_world.srec
3702 1 2 3 4 5 6 7 8 9 10 11 ...
3703 [file transfer complete]
3705 ## Start Addr = 0x00040004
3707 => go 40004 Hello World! This is a test.
3708 ## Starting application at 0x00040004 ...
3719 Hit any key to exit ...
3721 ## Application terminated, rc = 0x0
3723 Another example, which demonstrates how to register a CPM interrupt
3724 handler with the U-Boot code, can be found in 'examples/timer.c'.
3725 Here, a CPM timer is set up to generate an interrupt every second.
3726 The interrupt service routine is trivial, just printing a '.'
3727 character, but this is just a demo program. The application can be
3728 controlled by the following keys:
3730 ? - print current values og the CPM Timer registers
3731 b - enable interrupts and start timer
3732 e - stop timer and disable interrupts
3733 q - quit application
3736 ## Ready for S-Record download ...
3737 ~>examples/timer.srec
3738 1 2 3 4 5 6 7 8 9 10 11 ...
3739 [file transfer complete]
3741 ## Start Addr = 0x00040004
3744 ## Starting application at 0x00040004 ...
3747 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
3750 [q, b, e, ?] Set interval 1000000 us
3753 [q, b, e, ?] ........
3754 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
3757 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
3760 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
3763 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
3765 [q, b, e, ?] ...Stopping timer
3767 [q, b, e, ?] ## Application terminated, rc = 0x0
3773 Over time, many people have reported problems when trying to use the
3774 "minicom" terminal emulation program for serial download. I (wd)
3775 consider minicom to be broken, and recommend not to use it. Under
3776 Unix, I recommend to use C-Kermit for general purpose use (and
3777 especially for kermit binary protocol download ("loadb" command), and
3778 use "cu" for S-Record download ("loads" command).
3780 Nevertheless, if you absolutely want to use it try adding this
3781 configuration to your "File transfer protocols" section:
3783 Name Program Name U/D FullScr IO-Red. Multi
3784 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
3785 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
3791 Starting at version 0.9.2, U-Boot supports NetBSD both as host
3792 (build U-Boot) and target system (boots NetBSD/mpc8xx).
3794 Building requires a cross environment; it is known to work on
3795 NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
3796 need gmake since the Makefiles are not compatible with BSD make).
3797 Note that the cross-powerpc package does not install include files;
3798 attempting to build U-Boot will fail because <machine/ansi.h> is
3799 missing. This file has to be installed and patched manually:
3801 # cd /usr/pkg/cross/powerpc-netbsd/include
3803 # ln -s powerpc machine
3804 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
3805 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
3807 Native builds *don't* work due to incompatibilities between native
3808 and U-Boot include files.
3810 Booting assumes that (the first part of) the image booted is a
3811 stage-2 loader which in turn loads and then invokes the kernel
3812 proper. Loader sources will eventually appear in the NetBSD source
3813 tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
3814 meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
3817 Implementation Internals:
3818 =========================
3820 The following is not intended to be a complete description of every
3821 implementation detail. However, it should help to understand the
3822 inner workings of U-Boot and make it easier to port it to custom
3826 Initial Stack, Global Data:
3827 ---------------------------
3829 The implementation of U-Boot is complicated by the fact that U-Boot
3830 starts running out of ROM (flash memory), usually without access to
3831 system RAM (because the memory controller is not initialized yet).
3832 This means that we don't have writable Data or BSS segments, and BSS
3833 is not initialized as zero. To be able to get a C environment working
3834 at all, we have to allocate at least a minimal stack. Implementation
3835 options for this are defined and restricted by the CPU used: Some CPU
3836 models provide on-chip memory (like the IMMR area on MPC8xx and
3837 MPC826x processors), on others (parts of) the data cache can be
3838 locked as (mis-) used as memory, etc.
3840 Chris Hallinan posted a good summary of these issues to the
3841 U-Boot mailing list:
3843 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
3844 From: "Chris Hallinan" <clh@net1plus.com>
3845 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
3848 Correct me if I'm wrong, folks, but the way I understand it
3849 is this: Using DCACHE as initial RAM for Stack, etc, does not
3850 require any physical RAM backing up the cache. The cleverness
3851 is that the cache is being used as a temporary supply of
3852 necessary storage before the SDRAM controller is setup. It's
3853 beyond the scope of this list to explain the details, but you
3854 can see how this works by studying the cache architecture and
3855 operation in the architecture and processor-specific manuals.
3857 OCM is On Chip Memory, which I believe the 405GP has 4K. It
3858 is another option for the system designer to use as an
3859 initial stack/RAM area prior to SDRAM being available. Either
3860 option should work for you. Using CS 4 should be fine if your
3861 board designers haven't used it for something that would
3862 cause you grief during the initial boot! It is frequently not
3865 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere
3866 with your processor/board/system design. The default value
3867 you will find in any recent u-boot distribution in
3868 walnut.h should work for you. I'd set it to a value larger
3869 than your SDRAM module. If you have a 64MB SDRAM module, set
3870 it above 400_0000. Just make sure your board has no resources
3871 that are supposed to respond to that address! That code in
3872 start.S has been around a while and should work as is when
3873 you get the config right.
3878 It is essential to remember this, since it has some impact on the C
3879 code for the initialization procedures:
3881 * Initialized global data (data segment) is read-only. Do not attempt
3884 * Do not use any uninitialized global data (or implicitely initialized
3885 as zero data - BSS segment) at all - this is undefined, initiali-
3886 zation is performed later (when relocating to RAM).
3888 * Stack space is very limited. Avoid big data buffers or things like
3891 Having only the stack as writable memory limits means we cannot use
3892 normal global data to share information beween the code. But it
3893 turned out that the implementation of U-Boot can be greatly
3894 simplified by making a global data structure (gd_t) available to all
3895 functions. We could pass a pointer to this data as argument to _all_
3896 functions, but this would bloat the code. Instead we use a feature of
3897 the GCC compiler (Global Register Variables) to share the data: we
3898 place a pointer (gd) to the global data into a register which we
3899 reserve for this purpose.
3901 When choosing a register for such a purpose we are restricted by the
3902 relevant (E)ABI specifications for the current architecture, and by
3903 GCC's implementation.
3905 For PowerPC, the following registers have specific use:
3907 R2: reserved for system use
3908 R3-R4: parameter passing and return values
3909 R5-R10: parameter passing
3910 R13: small data area pointer
3914 (U-Boot also uses R14 as internal GOT pointer.)
3916 ==> U-Boot will use R2 to hold a pointer to the global data
3918 Note: on PPC, we could use a static initializer (since the
3919 address of the global data structure is known at compile time),
3920 but it turned out that reserving a register results in somewhat
3921 smaller code - although the code savings are not that big (on
3922 average for all boards 752 bytes for the whole U-Boot image,
3923 624 text + 127 data).
3925 On Blackfin, the normal C ABI (except for P3) is followed as documented here:
3926 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface
3928 ==> U-Boot will use P3 to hold a pointer to the global data
3930 On ARM, the following registers are used:
3932 R0: function argument word/integer result
3933 R1-R3: function argument word
3935 R10: stack limit (used only if stack checking if enabled)
3936 R11: argument (frame) pointer
3937 R12: temporary workspace
3940 R15: program counter
3942 ==> U-Boot will use R8 to hold a pointer to the global data
3944 NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
3945 or current versions of GCC may "optimize" the code too much.
3950 U-Boot runs in system state and uses physical addresses, i.e. the
3951 MMU is not used either for address mapping nor for memory protection.
3953 The available memory is mapped to fixed addresses using the memory
3954 controller. In this process, a contiguous block is formed for each
3955 memory type (Flash, SDRAM, SRAM), even when it consists of several
3956 physical memory banks.
3958 U-Boot is installed in the first 128 kB of the first Flash bank (on
3959 TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
3960 booting and sizing and initializing DRAM, the code relocates itself
3961 to the upper end of DRAM. Immediately below the U-Boot code some
3962 memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN
3963 configuration setting]. Below that, a structure with global Board
3964 Info data is placed, followed by the stack (growing downward).
3966 Additionally, some exception handler code is copied to the low 8 kB
3967 of DRAM (0x00000000 ... 0x00001FFF).
3969 So a typical memory configuration with 16 MB of DRAM could look like
3972 0x0000 0000 Exception Vector code
3975 0x0000 2000 Free for Application Use
3981 0x00FB FF20 Monitor Stack (Growing downward)
3982 0x00FB FFAC Board Info Data and permanent copy of global data
3983 0x00FC 0000 Malloc Arena
3986 0x00FE 0000 RAM Copy of Monitor Code
3987 ... eventually: LCD or video framebuffer
3988 ... eventually: pRAM (Protected RAM - unchanged by reset)
3989 0x00FF FFFF [End of RAM]
3992 System Initialization:
3993 ----------------------
3995 In the reset configuration, U-Boot starts at the reset entry point
3996 (on most PowerPC systems at address 0x00000100). Because of the reset
3997 configuration for CS0# this is a mirror of the onboard Flash memory.
3998 To be able to re-map memory U-Boot then jumps to its link address.
3999 To be able to implement the initialization code in C, a (small!)
4000 initial stack is set up in the internal Dual Ported RAM (in case CPUs
4001 which provide such a feature like MPC8xx or MPC8260), or in a locked
4002 part of the data cache. After that, U-Boot initializes the CPU core,
4003 the caches and the SIU.
4005 Next, all (potentially) available memory banks are mapped using a
4006 preliminary mapping. For example, we put them on 512 MB boundaries
4007 (multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
4008 on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
4009 programmed for SDRAM access. Using the temporary configuration, a
4010 simple memory test is run that determines the size of the SDRAM
4013 When there is more than one SDRAM bank, and the banks are of
4014 different size, the largest is mapped first. For equal size, the first
4015 bank (CS2#) is mapped first. The first mapping is always for address
4016 0x00000000, with any additional banks following immediately to create
4017 contiguous memory starting from 0.
4019 Then, the monitor installs itself at the upper end of the SDRAM area
4020 and allocates memory for use by malloc() and for the global Board
4021 Info data; also, the exception vector code is copied to the low RAM
4022 pages, and the final stack is set up.
4024 Only after this relocation will you have a "normal" C environment;
4025 until that you are restricted in several ways, mostly because you are
4026 running from ROM, and because the code will have to be relocated to a
4030 U-Boot Porting Guide:
4031 ----------------------
4033 [Based on messages by Jerry Van Baren in the U-Boot-Users mailing
4037 int main(int argc, char *argv[])
4039 sighandler_t no_more_time;
4041 signal(SIGALRM, no_more_time);
4042 alarm(PROJECT_DEADLINE - toSec (3 * WEEK));
4044 if (available_money > available_manpower) {
4045 Pay consultant to port U-Boot;
4049 Download latest U-Boot source;
4051 Subscribe to u-boot mailing list;
4054 email("Hi, I am new to U-Boot, how do I get started?");
4057 Read the README file in the top level directory;
4058 Read http://www.denx.de/twiki/bin/view/DULG/Manual;
4059 Read applicable doc/*.README;
4060 Read the source, Luke;
4061 /* find . -name "*.[chS]" | xargs grep -i <keyword> */
4064 if (available_money > toLocalCurrency ($2500))
4067 Add a lot of aggravation and time;
4069 if (a similar board exists) { /* hopefully... */
4070 cp -a board/<similar> board/<myboard>
4071 cp include/configs/<similar>.h include/configs/<myboard>.h
4073 Create your own board support subdirectory;
4074 Create your own board include/configs/<myboard>.h file;
4076 Edit new board/<myboard> files
4077 Edit new include/configs/<myboard>.h
4082 Add / modify source code;
4086 email("Hi, I am having problems...");
4088 Send patch file to the U-Boot email list;
4089 if (reasonable critiques)
4090 Incorporate improvements from email list code review;
4092 Defend code as written;
4098 void no_more_time (int sig)
4107 All contributions to U-Boot should conform to the Linux kernel
4108 coding style; see the file "Documentation/CodingStyle" and the script
4109 "scripts/Lindent" in your Linux kernel source directory. In sources
4110 originating from U-Boot a style corresponding to "Lindent -pcs" (adding
4111 spaces before parameters to function calls) is actually used.
4113 Source files originating from a different project (for example the
4114 MTD subsystem) are generally exempt from these guidelines and are not
4115 reformated to ease subsequent migration to newer versions of those
4118 Please note that U-Boot is implemented in C (and to some small parts in
4119 Assembler); no C++ is used, so please do not use C++ style comments (//)
4122 Please also stick to the following formatting rules:
4123 - remove any trailing white space
4124 - use TAB characters for indentation, not spaces
4125 - make sure NOT to use DOS '\r\n' line feeds
4126 - do not add more than 2 empty lines to source files
4127 - do not add trailing empty lines to source files
4129 Submissions which do not conform to the standards may be returned
4130 with a request to reformat the changes.
4136 Since the number of patches for U-Boot is growing, we need to
4137 establish some rules. Submissions which do not conform to these rules
4138 may be rejected, even when they contain important and valuable stuff.
4140 Please see http://www.denx.de/wiki/U-Boot/Patches for details.
4142 Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>;
4143 see http://lists.denx.de/mailman/listinfo/u-boot
4145 When you send a patch, please include the following information with
4148 * For bug fixes: a description of the bug and how your patch fixes
4149 this bug. Please try to include a way of demonstrating that the
4150 patch actually fixes something.
4152 * For new features: a description of the feature and your
4155 * A CHANGELOG entry as plaintext (separate from the patch)
4157 * For major contributions, your entry to the CREDITS file
4159 * When you add support for a new board, don't forget to add this
4160 board to the MAKEALL script, too.
4162 * If your patch adds new configuration options, don't forget to
4163 document these in the README file.
4165 * The patch itself. If you are using git (which is *strongly*
4166 recommended) you can easily generate the patch using the
4167 "git-format-patch". If you then use "git-send-email" to send it to
4168 the U-Boot mailing list, you will avoid most of the common problems
4169 with some other mail clients.
4171 If you cannot use git, use "diff -purN OLD NEW". If your version of
4172 diff does not support these options, then get the latest version of
4175 The current directory when running this command shall be the parent
4176 directory of the U-Boot source tree (i. e. please make sure that
4177 your patch includes sufficient directory information for the
4180 We prefer patches as plain text. MIME attachments are discouraged,
4181 and compressed attachments must not be used.
4183 * If one logical set of modifications affects or creates several
4184 files, all these changes shall be submitted in a SINGLE patch file.
4186 * Changesets that contain different, unrelated modifications shall be
4187 submitted as SEPARATE patches, one patch per changeset.
4192 * Before sending the patch, run the MAKEALL script on your patched
4193 source tree and make sure that no errors or warnings are reported
4194 for any of the boards.
4196 * Keep your modifications to the necessary minimum: A patch
4197 containing several unrelated changes or arbitrary reformats will be
4198 returned with a request to re-formatting / split it.
4200 * If you modify existing code, make sure that your new code does not
4201 add to the memory footprint of the code ;-) Small is beautiful!
4202 When adding new features, these should compile conditionally only
4203 (using #ifdef), and the resulting code with the new feature
4204 disabled must not need more memory than the old code without your
4207 * Remember that there is a size limit of 100 kB per message on the
4208 u-boot mailing list. Bigger patches will be moderated. If they are
4209 reasonable and not too big, they will be acknowledged. But patches
4210 bigger than the size limit should be avoided.
projects / oweals / u-boot.git / blob