2 # (C) Copyright 2000 - 2005
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.
60 In case you have questions about, problems with or contributions for
61 U-Boot you should send a message to the U-Boot mailing list at
62 <u-boot-users@lists.sourceforge.net>. There is also an archive of
63 previous traffic on the mailing list - please search the archive
64 before asking FAQ's. Please see
65 http://lists.sourceforge.net/lists/listinfo/u-boot-users/
71 - start from 8xxrom sources
72 - create PPCBoot project (http://sourceforge.net/projects/ppcboot)
74 - make it easier to add custom boards
75 - make it possible to add other [PowerPC] CPUs
76 - extend functions, especially:
77 * Provide extended interface to Linux boot loader
80 * PCMCIA / CompactFLash / ATA disk / SCSI ... boot
81 - create ARMBoot project (http://sourceforge.net/projects/armboot)
82 - add other CPU families (starting with ARM)
83 - create U-Boot project (http://sourceforge.net/projects/u-boot)
89 The "official" name of this project is "Das U-Boot". The spelling
90 "U-Boot" shall be used in all written text (documentation, comments
91 in source files etc.). Example:
93 This is the README file for the U-Boot project.
95 File names etc. shall be based on the string "u-boot". Examples:
97 include/asm-ppc/u-boot.h
99 #include <asm/u-boot.h>
101 Variable names, preprocessor constants etc. shall be either based on
102 the string "u_boot" or on "U_BOOT". Example:
104 U_BOOT_VERSION u_boot_logo
105 IH_OS_U_BOOT u_boot_hush_start
111 U-Boot uses a 3 level version number containing a version, a
112 sub-version, and a patchlevel: "U-Boot-2.34.5" means version "2",
113 sub-version "34", and patchlevel "4".
115 The patchlevel is used to indicate certain stages of development
116 between released versions, i. e. officially released versions of
117 U-Boot will always have a patchlevel of "0".
123 - board Board dependent files
124 - common Misc architecture independent functions
125 - cpu CPU specific files
126 - 74xx_7xx Files specific to Freescale MPC74xx and 7xx CPUs
127 - arm720t Files specific to ARM 720 CPUs
128 - arm920t Files specific to ARM 920 CPUs
129 - at91rm9200 Files specific to Atmel AT91RM9200 CPU
130 - imx Files specific to Freescale MC9328 i.MX CPUs
131 - s3c24x0 Files specific to Samsung S3C24X0 CPUs
132 - arm925t Files specific to ARM 925 CPUs
133 - arm926ejs Files specific to ARM 926 CPUs
134 - arm1136 Files specific to ARM 1136 CPUs
135 - i386 Files specific to i386 CPUs
136 - ixp Files specific to Intel XScale IXP CPUs
137 - mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs
138 - mips Files specific to MIPS CPUs
139 - mpc5xx Files specific to Freescale MPC5xx CPUs
140 - mpc5xxx Files specific to Freescale MPC5xxx CPUs
141 - mpc8xx Files specific to Freescale MPC8xx CPUs
142 - mpc8220 Files specific to Freescale MPC8220 CPUs
143 - mpc824x Files specific to Freescale MPC824x CPUs
144 - mpc8260 Files specific to Freescale MPC8260 CPUs
145 - mpc85xx Files specific to Freescale MPC85xx CPUs
146 - nios Files specific to Altera NIOS CPUs
147 - nios2 Files specific to Altera Nios-II CPUs
148 - ppc4xx Files specific to AMCC PowerPC 4xx CPUs
149 - pxa Files specific to Intel XScale PXA CPUs
150 - s3c44b0 Files specific to Samsung S3C44B0 CPUs
151 - sa1100 Files specific to Intel StrongARM SA1100 CPUs
152 - disk Code for disk drive partition handling
153 - doc Documentation (don't expect too much)
154 - drivers Commonly used device drivers
155 - dtt Digital Thermometer and Thermostat drivers
156 - examples Example code for standalone applications, etc.
157 - include Header Files
158 - lib_arm Files generic to ARM architecture
159 - lib_generic Files generic to all architectures
160 - lib_i386 Files generic to i386 architecture
161 - lib_m68k Files generic to m68k architecture
162 - lib_mips Files generic to MIPS architecture
163 - lib_nios Files generic to NIOS architecture
164 - lib_ppc Files generic to PowerPC architecture
165 - net Networking code
166 - post Power On Self Test
167 - rtc Real Time Clock drivers
168 - tools Tools to build S-Record or U-Boot images, etc.
170 Software Configuration:
171 =======================
173 Configuration is usually done using C preprocessor defines; the
174 rationale behind that is to avoid dead code whenever possible.
176 There are two classes of configuration variables:
178 * Configuration _OPTIONS_:
179 These are selectable by the user and have names beginning with
182 * Configuration _SETTINGS_:
183 These depend on the hardware etc. and should not be meddled with if
184 you don't know what you're doing; they have names beginning with
187 Later we will add a configuration tool - probably similar to or even
188 identical to what's used for the Linux kernel. Right now, we have to
189 do the configuration by hand, which means creating some symbolic
190 links and editing some configuration files. We use the TQM8xxL boards
194 Selection of Processor Architecture and Board Type:
195 ---------------------------------------------------
197 For all supported boards there are ready-to-use default
198 configurations available; just type "make <board_name>_config".
200 Example: For a TQM823L module type:
205 For the Cogent platform, you need to specify the cpu type as well;
206 e.g. "make cogent_mpc8xx_config". And also configure the cogent
207 directory according to the instructions in cogent/README.
210 Configuration Options:
211 ----------------------
213 Configuration depends on the combination of board and CPU type; all
214 such information is kept in a configuration file
215 "include/configs/<board_name>.h".
217 Example: For a TQM823L module, all configuration settings are in
218 "include/configs/TQM823L.h".
221 Many of the options are named exactly as the corresponding Linux
222 kernel configuration options. The intention is to make it easier to
223 build a config tool - later.
226 The following options need to be configured:
228 - CPU Type: Define exactly one of
232 CONFIG_MPC823, CONFIG_MPC850, CONFIG_MPC855, CONFIG_MPC860
235 or CONFIG_MPC824X, CONFIG_MPC8260
250 MicroBlaze based CPUs:
251 ----------------------
255 ----------------------
259 - Board Type: Define exactly one of
261 PowerPC based boards:
262 ---------------------
264 CONFIG_ADCIOP CONFIG_GEN860T CONFIG_PCIPPC2
265 CONFIG_ADS860 CONFIG_GENIETV CONFIG_PCIPPC6
266 CONFIG_AMX860 CONFIG_GTH CONFIG_pcu_e
267 CONFIG_AP1000 CONFIG_gw8260 CONFIG_PIP405
268 CONFIG_AR405 CONFIG_hermes CONFIG_PM826
269 CONFIG_BAB7xx CONFIG_hymod CONFIG_ppmc8260
270 CONFIG_c2mon CONFIG_IAD210 CONFIG_QS823
271 CONFIG_CANBT CONFIG_ICU862 CONFIG_QS850
272 CONFIG_CCM CONFIG_IP860 CONFIG_QS860T
273 CONFIG_CMI CONFIG_IPHASE4539 CONFIG_RBC823
274 CONFIG_cogent_mpc8260 CONFIG_IVML24 CONFIG_RPXClassic
275 CONFIG_cogent_mpc8xx CONFIG_IVML24_128 CONFIG_RPXlite
276 CONFIG_CPCI405 CONFIG_IVML24_256 CONFIG_RPXsuper
277 CONFIG_CPCI4052 CONFIG_IVMS8 CONFIG_rsdproto
278 CONFIG_CPCIISER4 CONFIG_IVMS8_128 CONFIG_sacsng
279 CONFIG_CPU86 CONFIG_IVMS8_256 CONFIG_Sandpoint8240
280 CONFIG_CRAYL1 CONFIG_JSE CONFIG_Sandpoint8245
281 CONFIG_CSB272 CONFIG_LANTEC CONFIG_sbc8260
282 CONFIG_CU824 CONFIG_lwmon CONFIG_sbc8560
283 CONFIG_DASA_SIM CONFIG_MBX CONFIG_SM850
284 CONFIG_DB64360 CONFIG_MBX860T CONFIG_SPD823TS
285 CONFIG_DB64460 CONFIG_MHPC CONFIG_STXGP3
286 CONFIG_DU405 CONFIG_MIP405 CONFIG_SXNI855T
287 CONFIG_DUET_ADS CONFIG_MOUSSE CONFIG_TQM823L
288 CONFIG_EBONY CONFIG_MPC8260ADS CONFIG_TQM8260
289 CONFIG_ELPPC CONFIG_MPC8540ADS CONFIG_TQM850L
290 CONFIG_ELPT860 CONFIG_MPC8540EVAL CONFIG_TQM855L
291 CONFIG_ep8260 CONFIG_MPC8560ADS CONFIG_TQM860L
292 CONFIG_ERIC CONFIG_MUSENKI CONFIG_TTTech
293 CONFIG_ESTEEM192E CONFIG_MVS1 CONFIG_UTX8245
294 CONFIG_ETX094 CONFIG_NETPHONE CONFIG_V37
295 CONFIG_EVB64260 CONFIG_NETTA CONFIG_W7OLMC
296 CONFIG_FADS823 CONFIG_NETVIA CONFIG_W7OLMG
297 CONFIG_FADS850SAR CONFIG_NX823 CONFIG_WALNUT
298 CONFIG_FADS860T CONFIG_OCRTC CONFIG_ZPC1900
299 CONFIG_FLAGADM CONFIG_ORSG CONFIG_ZUMA
300 CONFIG_FPS850L CONFIG_OXC
301 CONFIG_FPS860L CONFIG_PCI405
306 CONFIG_ARMADILLO, CONFIG_AT91RM9200DK, CONFIG_CERF250,
307 CONFIG_CSB637, CONFIG_DNP1110, CONFIG_EP7312,
308 CONFIG_H2_OMAP1610, CONFIG_HHP_CRADLE, CONFIG_IMPA7,
309 CONFIG_INNOVATOROMAP1510, CONFIG_INNOVATOROMAP1610, CONFIG_KB9202,
310 CONFIG_LART, CONFIG_LPD7A400, CONFIG_LUBBOCK,
311 CONFIG_OSK_OMAP5912, CONFIG_OMAP2420H4, CONFIG_SHANNON,
312 CONFIG_P2_OMAP730, CONFIG_SMDK2400, CONFIG_SMDK2410,
313 CONFIG_TRAB, CONFIG_VCMA9
315 MicroBlaze based boards:
316 ------------------------
321 ------------------------
323 CONFIG_PCI5441 CONFIG_PK1C20
326 - CPU Module Type: (if CONFIG_COGENT is defined)
327 Define exactly one of
329 --- FIXME --- not tested yet:
330 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P,
331 CONFIG_CMA287_23, CONFIG_CMA287_50
333 - Motherboard Type: (if CONFIG_COGENT is defined)
334 Define exactly one of
335 CONFIG_CMA101, CONFIG_CMA102
337 - Motherboard I/O Modules: (if CONFIG_COGENT is defined)
338 Define one or more of
341 - Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined)
342 Define one or more of
343 CONFIG_LCD_HEARTBEAT - update a character position on
344 the lcd display every second with
347 - Board flavour: (if CONFIG_MPC8260ADS is defined)
350 CFG_8260ADS - original MPC8260ADS
351 CFG_8266ADS - MPC8266ADS
352 CFG_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR
353 CFG_8272ADS - MPC8272ADS
355 - MPC824X Family Member (if CONFIG_MPC824X is defined)
356 Define exactly one of
357 CONFIG_MPC8240, CONFIG_MPC8245
359 - 8xx CPU Options: (if using an MPC8xx cpu)
360 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if
361 get_gclk_freq() cannot work
362 e.g. if there is no 32KHz
363 reference PIT/RTC clock
364 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK
367 - 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU):
370 CONFIG_8xx_CPUCLK_DEFAULT
371 See doc/README.MPC866
375 Define this to measure the actual CPU clock instead
376 of relying on the correctness of the configured
377 values. Mostly useful for board bringup to make sure
378 the PLL is locked at the intended frequency. Note
379 that this requires a (stable) reference clock (32 kHz
380 RTC clock or CFG_8XX_XIN)
382 - Linux Kernel Interface:
385 U-Boot stores all clock information in Hz
386 internally. For binary compatibility with older Linux
387 kernels (which expect the clocks passed in the
388 bd_info data to be in MHz) the environment variable
389 "clocks_in_mhz" can be defined so that U-Boot
390 converts clock data to MHZ before passing it to the
392 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
393 "clocks_in_mhz=1" is automatically included in the
396 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
398 When transfering memsize parameter to linux, some versions
399 expect it to be in bytes, others in MB.
400 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
405 Define this if you want support for Amba PrimeCell PL010 UARTs.
409 Define this if you want support for Amba PrimeCell PL011 UARTs.
413 If you have Amba PrimeCell PL011 UARTs, set this variable to
414 the clock speed of the UARTs.
418 If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
419 define this to a list of base addresses for each (supported)
420 port. See e.g. include/configs/versatile.h
424 Depending on board, define exactly one serial port
425 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
426 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial
427 console by defining CONFIG_8xx_CONS_NONE
429 Note: if CONFIG_8xx_CONS_NONE is defined, the serial
430 port routines must be defined elsewhere
431 (i.e. serial_init(), serial_getc(), ...)
434 Enables console device for a color framebuffer. Needs following
435 defines (cf. smiLynxEM, i8042, board/eltec/bab7xx)
436 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation
438 VIDEO_HW_RECTFILL graphic chip supports
441 VIDEO_HW_BITBLT graphic chip supports
442 bit-blit (cf. smiLynxEM)
443 VIDEO_VISIBLE_COLS visible pixel columns
445 VIDEO_VISIBLE_ROWS visible pixel rows
446 VIDEO_PIXEL_SIZE bytes per pixel
447 VIDEO_DATA_FORMAT graphic data format
448 (0-5, cf. cfb_console.c)
449 VIDEO_FB_ADRS framebuffer address
450 VIDEO_KBD_INIT_FCT keyboard int fct
451 (i.e. i8042_kbd_init())
452 VIDEO_TSTC_FCT test char fct
454 VIDEO_GETC_FCT get char fct
456 CONFIG_CONSOLE_CURSOR cursor drawing on/off
457 (requires blink timer
459 CFG_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c)
460 CONFIG_CONSOLE_TIME display time/date info in
462 (requires CFG_CMD_DATE)
463 CONFIG_VIDEO_LOGO display Linux logo in
465 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of
466 linux_logo.h for logo.
467 Requires CONFIG_VIDEO_LOGO
468 CONFIG_CONSOLE_EXTRA_INFO
469 addional board info beside
472 When CONFIG_CFB_CONSOLE is defined, video console is
473 default i/o. Serial console can be forced with
474 environment 'console=serial'.
476 When CONFIG_SILENT_CONSOLE is defined, all console
477 messages (by U-Boot and Linux!) can be silenced with
478 the "silent" environment variable. See
479 doc/README.silent for more information.
482 CONFIG_BAUDRATE - in bps
483 Select one of the baudrates listed in
484 CFG_BAUDRATE_TABLE, see below.
485 CFG_BRGCLK_PRESCALE, baudrate prescale
487 - Interrupt driven serial port input:
488 CONFIG_SERIAL_SOFTWARE_FIFO
491 Use an interrupt handler for receiving data on the
492 serial port. It also enables using hardware handshake
493 (RTS/CTS) and UART's built-in FIFO. Set the number of
494 bytes the interrupt driven input buffer should have.
496 Leave undefined to disable this feature, including
497 disable the buffer and hardware handshake.
499 - Console UART Number:
503 If defined internal UART1 (and not UART0) is used
504 as default U-Boot console.
506 - Boot Delay: CONFIG_BOOTDELAY - in seconds
507 Delay before automatically booting the default image;
508 set to -1 to disable autoboot.
510 See doc/README.autoboot for these options that
511 work with CONFIG_BOOTDELAY. None are required.
512 CONFIG_BOOT_RETRY_TIME
513 CONFIG_BOOT_RETRY_MIN
514 CONFIG_AUTOBOOT_KEYED
515 CONFIG_AUTOBOOT_PROMPT
516 CONFIG_AUTOBOOT_DELAY_STR
517 CONFIG_AUTOBOOT_STOP_STR
518 CONFIG_AUTOBOOT_DELAY_STR2
519 CONFIG_AUTOBOOT_STOP_STR2
520 CONFIG_ZERO_BOOTDELAY_CHECK
521 CONFIG_RESET_TO_RETRY
525 Only needed when CONFIG_BOOTDELAY is enabled;
526 define a command string that is automatically executed
527 when no character is read on the console interface
528 within "Boot Delay" after reset.
531 This can be used to pass arguments to the bootm
532 command. The value of CONFIG_BOOTARGS goes into the
533 environment value "bootargs".
535 CONFIG_RAMBOOT and CONFIG_NFSBOOT
536 The value of these goes into the environment as
537 "ramboot" and "nfsboot" respectively, and can be used
538 as a convenience, when switching between booting from
544 When this option is #defined, the existence of the
545 environment variable "preboot" will be checked
546 immediately before starting the CONFIG_BOOTDELAY
547 countdown and/or running the auto-boot command resp.
548 entering interactive mode.
550 This feature is especially useful when "preboot" is
551 automatically generated or modified. For an example
552 see the LWMON board specific code: here "preboot" is
553 modified when the user holds down a certain
554 combination of keys on the (special) keyboard when
557 - Serial Download Echo Mode:
559 If defined to 1, all characters received during a
560 serial download (using the "loads" command) are
561 echoed back. This might be needed by some terminal
562 emulations (like "cu"), but may as well just take
563 time on others. This setting #define's the initial
564 value of the "loads_echo" environment variable.
566 - Kgdb Serial Baudrate: (if CFG_CMD_KGDB is defined)
568 Select one of the baudrates listed in
569 CFG_BAUDRATE_TABLE, see below.
573 Most monitor functions can be selected (or
574 de-selected) by adjusting the definition of
575 CONFIG_COMMANDS; to select individual functions,
576 #define CONFIG_COMMANDS by "OR"ing any of the
579 #define enables commands:
580 -------------------------
581 CFG_CMD_ASKENV * ask for env variable
582 CFG_CMD_AUTOSCRIPT Autoscript Support
584 CFG_CMD_BEDBUG * Include BedBug Debugger
585 CFG_CMD_BMP * BMP support
586 CFG_CMD_BSP * Board specific commands
588 CFG_CMD_CACHE * icache, dcache
589 CFG_CMD_CONSOLE coninfo
590 CFG_CMD_DATE * support for RTC, date/time...
591 CFG_CMD_DHCP * DHCP support
592 CFG_CMD_DIAG * Diagnostics
593 CFG_CMD_DOC * Disk-On-Chip Support
594 CFG_CMD_DTT * Digital Therm and Thermostat
595 CFG_CMD_ECHO * echo arguments
596 CFG_CMD_EEPROM * EEPROM read/write support
597 CFG_CMD_ELF * bootelf, bootvx
599 CFG_CMD_FDC * Floppy Disk Support
600 CFG_CMD_FAT * FAT partition support
601 CFG_CMD_FDOS * Dos diskette Support
602 CFG_CMD_FLASH flinfo, erase, protect
603 CFG_CMD_FPGA FPGA device initialization support
604 CFG_CMD_HWFLOW * RTS/CTS hw flow control
605 CFG_CMD_I2C * I2C serial bus support
606 CFG_CMD_IDE * IDE harddisk support
608 CFG_CMD_IMLS List all found images
609 CFG_CMD_IMMAP * IMMR dump support
610 CFG_CMD_IRQ * irqinfo
611 CFG_CMD_ITEST Integer/string test of 2 values
612 CFG_CMD_JFFS2 * JFFS2 Support
616 CFG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base,
618 CFG_CMD_MISC Misc functions like sleep etc
619 CFG_CMD_MMC * MMC memory mapped support
620 CFG_CMD_MII * MII utility commands
621 CFG_CMD_NAND * NAND support
622 CFG_CMD_NET bootp, tftpboot, rarpboot
623 CFG_CMD_PCI * pciinfo
624 CFG_CMD_PCMCIA * PCMCIA support
625 CFG_CMD_PING * send ICMP ECHO_REQUEST to network host
626 CFG_CMD_PORTIO * Port I/O
627 CFG_CMD_REGINFO * Register dump
628 CFG_CMD_RUN run command in env variable
629 CFG_CMD_SAVES * save S record dump
630 CFG_CMD_SCSI * SCSI Support
631 CFG_CMD_SDRAM * print SDRAM configuration information
632 (requires CFG_CMD_I2C)
633 CFG_CMD_SETGETDCR Support for DCR Register access (4xx only)
634 CFG_CMD_SPI * SPI serial bus support
635 CFG_CMD_USB * USB support
636 CFG_CMD_VFD * VFD support (TRAB)
637 CFG_CMD_BSP * Board SPecific functions
638 CFG_CMD_CDP * Cisco Discover Protocol support
639 -----------------------------------------------
642 CONFIG_CMD_DFL Default configuration; at the moment
643 this is includes all commands, except
644 the ones marked with "*" in the list
647 If you don't define CONFIG_COMMANDS it defaults to
648 CONFIG_CMD_DFL in include/cmd_confdefs.h. A board can
649 override the default settings in the respective
652 EXAMPLE: If you want all functions except of network
653 support you can write:
655 #define CONFIG_COMMANDS (CFG_CMD_ALL & ~CFG_CMD_NET)
658 Note: Don't enable the "icache" and "dcache" commands
659 (configuration option CFG_CMD_CACHE) unless you know
660 what you (and your U-Boot users) are doing. Data
661 cache cannot be enabled on systems like the 8xx or
662 8260 (where accesses to the IMMR region must be
663 uncached), and it cannot be disabled on all other
664 systems where we (mis-) use the data cache to hold an
665 initial stack and some data.
668 XXX - this list needs to get updated!
672 If this variable is defined, it enables watchdog
673 support. There must be support in the platform specific
674 code for a watchdog. For the 8xx and 8260 CPUs, the
675 SIU Watchdog feature is enabled in the SYPCR
679 CONFIG_VERSION_VARIABLE
680 If this variable is defined, an environment variable
681 named "ver" is created by U-Boot showing the U-Boot
682 version as printed by the "version" command.
683 This variable is readonly.
687 When CFG_CMD_DATE is selected, the type of the RTC
688 has to be selected, too. Define exactly one of the
691 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx
692 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
693 CONFIG_RTC_MC146818 - use MC146818 RTC
694 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
695 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
696 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
697 CONFIG_RTC_DS164x - use Dallas DS164x RTC
698 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
700 Note that if the RTC uses I2C, then the I2C interface
701 must also be configured. See I2C Support, below.
705 When CONFIG_TIMESTAMP is selected, the timestamp
706 (date and time) of an image is printed by image
707 commands like bootm or iminfo. This option is
708 automatically enabled when you select CFG_CMD_DATE .
711 CONFIG_MAC_PARTITION and/or CONFIG_DOS_PARTITION
712 and/or CONFIG_ISO_PARTITION
714 If IDE or SCSI support is enabled (CFG_CMD_IDE or
715 CFG_CMD_SCSI) you must configure support for at least
716 one partition type as well.
719 CONFIG_IDE_RESET_ROUTINE - this is defined in several
720 board configurations files but used nowhere!
722 CONFIG_IDE_RESET - is this is defined, IDE Reset will
723 be performed by calling the function
724 ide_set_reset(int reset)
725 which has to be defined in a board specific file
730 Set this to enable ATAPI support.
735 Set this to enable support for disks larger than 137GB
736 Also look at CFG_64BIT_LBA ,CFG_64BIT_VSPRINTF and CFG_64BIT_STRTOUL
737 Whithout these , LBA48 support uses 32bit variables and will 'only'
738 support disks up to 2.1TB.
741 When enabled, makes the IDE subsystem use 64bit sector addresses.
745 At the moment only there is only support for the
746 SYM53C8XX SCSI controller; define
747 CONFIG_SCSI_SYM53C8XX to enable it.
749 CFG_SCSI_MAX_LUN [8], CFG_SCSI_MAX_SCSI_ID [7] and
750 CFG_SCSI_MAX_DEVICE [CFG_SCSI_MAX_SCSI_ID *
751 CFG_SCSI_MAX_LUN] can be adjusted to define the
752 maximum numbers of LUNs, SCSI ID's and target
754 CFG_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
756 - NETWORK Support (PCI):
758 Support for Intel 8254x gigabit chips.
761 Support for Intel 82557/82559/82559ER chips.
762 Optional CONFIG_EEPRO100_SROM_WRITE enables eeprom
763 write routine for first time initialisation.
766 Support for Digital 2114x chips.
767 Optional CONFIG_TULIP_SELECT_MEDIA for board specific
768 modem chip initialisation (KS8761/QS6611).
771 Support for National dp83815 chips.
774 Support for National dp8382[01] gigabit chips.
776 - NETWORK Support (other):
778 CONFIG_DRIVER_LAN91C96
779 Support for SMSC's LAN91C96 chips.
782 Define this to hold the physical address
783 of the LAN91C96's I/O space
785 CONFIG_LAN91C96_USE_32_BIT
786 Define this to enable 32 bit addressing
788 CONFIG_DRIVER_SMC91111
789 Support for SMSC's LAN91C111 chip
792 Define this to hold the physical address
793 of the device (I/O space)
795 CONFIG_SMC_USE_32_BIT
796 Define this if data bus is 32 bits
798 CONFIG_SMC_USE_IOFUNCS
799 Define this to use i/o functions instead of macros
800 (some hardware wont work with macros)
803 At the moment only the UHCI host controller is
804 supported (PIP405, MIP405, MPC5200); define
805 CONFIG_USB_UHCI to enable it.
806 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
807 and define CONFIG_USB_STORAGE to enable the USB
810 Supported are USB Keyboards and USB Floppy drives
812 MPC5200 USB requires additional defines:
814 for 528 MHz Clock: 0x0001bbbb
816 for differential drivers: 0x00001000
817 for single ended drivers: 0x00005000
821 The MMC controller on the Intel PXA is supported. To
822 enable this define CONFIG_MMC. The MMC can be
823 accessed from the boot prompt by mapping the device
824 to physical memory similar to flash. Command line is
825 enabled with CFG_CMD_MMC. The MMC driver also works with
826 the FAT fs. This is enabled with CFG_CMD_FAT.
828 - Journaling Flash filesystem support:
829 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE,
830 CONFIG_JFFS2_NAND_DEV
831 Define these for a default partition on a NAND device
833 CFG_JFFS2_FIRST_SECTOR,
834 CFG_JFFS2_FIRST_BANK, CFG_JFFS2_NUM_BANKS
835 Define these for a default partition on a NOR device
838 Define this to create an own partition. You have to provide a
839 function struct part_info* jffs2_part_info(int part_num)
841 If you define only one JFFS2 partition you may also want to
842 #define CFG_JFFS_SINGLE_PART 1
843 to disable the command chpart. This is the default when you
844 have not defined a custom partition
849 Define this to enable standard (PC-Style) keyboard
853 Standard PC keyboard driver with US (is default) and
854 GERMAN key layout (switch via environment 'keymap=de') support.
855 Export function i8042_kbd_init, i8042_tstc and i8042_getc
856 for cfb_console. Supports cursor blinking.
861 Define this to enable video support (for output to
866 Enable Chips & Technologies 69000 Video chip
868 CONFIG_VIDEO_SMI_LYNXEM
869 Enable Silicon Motion SMI 712/710/810 Video chip. The
870 video output is selected via environment 'videoout'
871 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is
874 For the CT69000 and SMI_LYNXEM drivers, videomode is
875 selected via environment 'videomode'. Two diferent ways
877 - "videomode=num" 'num' is a standard LiLo mode numbers.
878 Following standard modes are supported (* is default):
880 Colors 640x480 800x600 1024x768 1152x864 1280x1024
881 -------------+---------------------------------------------
882 8 bits | 0x301* 0x303 0x305 0x161 0x307
883 15 bits | 0x310 0x313 0x316 0x162 0x319
884 16 bits | 0x311 0x314 0x317 0x163 0x31A
885 24 bits | 0x312 0x315 0x318 ? 0x31B
886 -------------+---------------------------------------------
887 (i.e. setenv videomode 317; saveenv; reset;)
889 - "videomode=bootargs" all the video parameters are parsed
890 from the bootargs. (See drivers/videomodes.c)
893 CONFIG_VIDEO_SED13806
894 Enable Epson SED13806 driver. This driver supports 8bpp
895 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
896 or CONFIG_VIDEO_SED13806_16BPP
901 Define this to enable a custom keyboard support.
902 This simply calls drv_keyboard_init() which must be
903 defined in your board-specific files.
904 The only board using this so far is RBC823.
906 - LCD Support: CONFIG_LCD
908 Define this to enable LCD support (for output to LCD
909 display); also select one of the supported displays
910 by defining one of these:
912 CONFIG_NEC_NL6448AC33:
914 NEC NL6448AC33-18. Active, color, single scan.
916 CONFIG_NEC_NL6448BC20
918 NEC NL6448BC20-08. 6.5", 640x480.
919 Active, color, single scan.
921 CONFIG_NEC_NL6448BC33_54
923 NEC NL6448BC33-54. 10.4", 640x480.
924 Active, color, single scan.
928 Sharp 320x240. Active, color, single scan.
929 It isn't 16x9, and I am not sure what it is.
931 CONFIG_SHARP_LQ64D341
933 Sharp LQ64D341 display, 640x480.
934 Active, color, single scan.
938 HLD1045 display, 640x480.
939 Active, color, single scan.
943 Optrex CBL50840-2 NF-FW 99 22 M5
945 Hitachi LMG6912RPFC-00T
949 320x240. Black & white.
951 Normally display is black on white background; define
952 CFG_WHITE_ON_BLACK to get it inverted.
954 - Splash Screen Support: CONFIG_SPLASH_SCREEN
956 If this option is set, the environment is checked for
957 a variable "splashimage". If found, the usual display
958 of logo, copyright and system information on the LCD
959 is suppressed and the BMP image at the address
960 specified in "splashimage" is loaded instead. The
961 console is redirected to the "nulldev", too. This
962 allows for a "silent" boot where a splash screen is
963 loaded very quickly after power-on.
965 - Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
967 If this option is set, additionally to standard BMP
968 images, gzipped BMP images can be displayed via the
969 splashscreen support or the bmp command.
971 - Compression support:
974 If this option is set, support for bzip2 compressed
975 images is included. If not, only uncompressed and gzip
976 compressed images are supported.
978 NOTE: the bzip2 algorithm requires a lot of RAM, so
979 the malloc area (as defined by CFG_MALLOC_LEN) should
985 The address of PHY on MII bus.
987 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
989 The clock frequency of the MII bus
993 If this option is set, support for speed/duplex
994 detection of Gigabit PHY is included.
996 CONFIG_PHY_RESET_DELAY
998 Some PHY like Intel LXT971A need extra delay after
999 reset before any MII register access is possible.
1000 For such PHY, set this option to the usec delay
1001 required. (minimum 300usec for LXT971A)
1003 CONFIG_PHY_CMD_DELAY (ppc4xx)
1005 Some PHY like Intel LXT971A need extra delay after
1006 command issued before MII status register can be read
1013 Define a default value for ethernet address to use
1014 for the respective ethernet interface, in case this
1015 is not determined automatically.
1020 Define a default value for the IP address to use for
1021 the default ethernet interface, in case this is not
1022 determined through e.g. bootp.
1024 - Server IP address:
1027 Defines a default value for theIP address of a TFTP
1028 server to contact when using the "tftboot" command.
1030 - BOOTP Recovery Mode:
1031 CONFIG_BOOTP_RANDOM_DELAY
1033 If you have many targets in a network that try to
1034 boot using BOOTP, you may want to avoid that all
1035 systems send out BOOTP requests at precisely the same
1036 moment (which would happen for instance at recovery
1037 from a power failure, when all systems will try to
1038 boot, thus flooding the BOOTP server. Defining
1039 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
1040 inserted before sending out BOOTP requests. The
1041 following delays are insterted then:
1043 1st BOOTP request: delay 0 ... 1 sec
1044 2nd BOOTP request: delay 0 ... 2 sec
1045 3rd BOOTP request: delay 0 ... 4 sec
1047 BOOTP requests: delay 0 ... 8 sec
1049 - DHCP Advanced Options:
1052 You can fine tune the DHCP functionality by adding
1053 these flags to the CONFIG_BOOTP_MASK define:
1055 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
1056 serverip from a DHCP server, it is possible that more
1057 than one DNS serverip is offered to the client.
1058 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
1059 serverip will be stored in the additional environment
1060 variable "dnsip2". The first DNS serverip is always
1061 stored in the variable "dnsip", when CONFIG_BOOTP_DNS
1062 is added to the CONFIG_BOOTP_MASK.
1064 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
1065 to do a dynamic update of a DNS server. To do this, they
1066 need the hostname of the DHCP requester.
1067 If CONFIG_BOOP_SEND_HOSTNAME is added to the
1068 CONFIG_BOOTP_MASK, the content of the "hostname"
1069 environment variable is passed as option 12 to
1073 CONFIG_CDP_DEVICE_ID
1075 The device id used in CDP trigger frames.
1077 CONFIG_CDP_DEVICE_ID_PREFIX
1079 A two character string which is prefixed to the MAC address
1084 A printf format string which contains the ascii name of
1085 the port. Normally is set to "eth%d" which sets
1086 eth0 for the first ethernet, eth1 for the second etc.
1088 CONFIG_CDP_CAPABILITIES
1090 A 32bit integer which indicates the device capabilities;
1091 0x00000010 for a normal host which does not forwards.
1095 An ascii string containing the version of the software.
1099 An ascii string containing the name of the platform.
1103 A 32bit integer sent on the trigger.
1105 CONFIG_CDP_POWER_CONSUMPTION
1107 A 16bit integer containing the power consumption of the
1108 device in .1 of milliwatts.
1110 CONFIG_CDP_APPLIANCE_VLAN_TYPE
1112 A byte containing the id of the VLAN.
1114 - Status LED: CONFIG_STATUS_LED
1116 Several configurations allow to display the current
1117 status using a LED. For instance, the LED will blink
1118 fast while running U-Boot code, stop blinking as
1119 soon as a reply to a BOOTP request was received, and
1120 start blinking slow once the Linux kernel is running
1121 (supported by a status LED driver in the Linux
1122 kernel). Defining CONFIG_STATUS_LED enables this
1125 - CAN Support: CONFIG_CAN_DRIVER
1127 Defining CONFIG_CAN_DRIVER enables CAN driver support
1128 on those systems that support this (optional)
1129 feature, like the TQM8xxL modules.
1131 - I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C
1133 These enable I2C serial bus commands. Defining either of
1134 (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will
1135 include the appropriate I2C driver for the selected cpu.
1137 This will allow you to use i2c commands at the u-boot
1138 command line (as long as you set CFG_CMD_I2C in
1139 CONFIG_COMMANDS) and communicate with i2c based realtime
1140 clock chips. See common/cmd_i2c.c for a description of the
1141 command line interface.
1143 CONFIG_HARD_I2C selects the CPM hardware driver for I2C.
1145 CONFIG_SOFT_I2C configures u-boot to use a software (aka
1146 bit-banging) driver instead of CPM or similar hardware
1149 There are several other quantities that must also be
1150 defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C.
1152 In both cases you will need to define CFG_I2C_SPEED
1153 to be the frequency (in Hz) at which you wish your i2c bus
1154 to run and CFG_I2C_SLAVE to be the address of this node (ie
1155 the cpu's i2c node address).
1157 Now, the u-boot i2c code for the mpc8xx (cpu/mpc8xx/i2c.c)
1158 sets the cpu up as a master node and so its address should
1159 therefore be cleared to 0 (See, eg, MPC823e User's Manual
1160 p.16-473). So, set CFG_I2C_SLAVE to 0.
1162 That's all that's required for CONFIG_HARD_I2C.
1164 If you use the software i2c interface (CONFIG_SOFT_I2C)
1165 then the following macros need to be defined (examples are
1166 from include/configs/lwmon.h):
1170 (Optional). Any commands necessary to enable the I2C
1171 controller or configure ports.
1173 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
1177 (Only for MPC8260 CPU). The I/O port to use (the code
1178 assumes both bits are on the same port). Valid values
1179 are 0..3 for ports A..D.
1183 The code necessary to make the I2C data line active
1184 (driven). If the data line is open collector, this
1187 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
1191 The code necessary to make the I2C data line tri-stated
1192 (inactive). If the data line is open collector, this
1195 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
1199 Code that returns TRUE if the I2C data line is high,
1202 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
1206 If <bit> is TRUE, sets the I2C data line high. If it
1207 is FALSE, it clears it (low).
1209 eg: #define I2C_SDA(bit) \
1210 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
1211 else immr->im_cpm.cp_pbdat &= ~PB_SDA
1215 If <bit> is TRUE, sets the I2C clock line high. If it
1216 is FALSE, it clears it (low).
1218 eg: #define I2C_SCL(bit) \
1219 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
1220 else immr->im_cpm.cp_pbdat &= ~PB_SCL
1224 This delay is invoked four times per clock cycle so this
1225 controls the rate of data transfer. The data rate thus
1226 is 1 / (I2C_DELAY * 4). Often defined to be something
1229 #define I2C_DELAY udelay(2)
1233 When a board is reset during an i2c bus transfer
1234 chips might think that the current transfer is still
1235 in progress. On some boards it is possible to access
1236 the i2c SCLK line directly, either by using the
1237 processor pin as a GPIO or by having a second pin
1238 connected to the bus. If this option is defined a
1239 custom i2c_init_board() routine in boards/xxx/board.c
1240 is run early in the boot sequence.
1242 CONFIG_I2CFAST (PPC405GP|PPC405EP only)
1244 This option enables configuration of bi_iic_fast[] flags
1245 in u-boot bd_info structure based on u-boot environment
1246 variable "i2cfast". (see also i2cfast)
1248 - SPI Support: CONFIG_SPI
1250 Enables SPI driver (so far only tested with
1251 SPI EEPROM, also an instance works with Crystal A/D and
1252 D/As on the SACSng board)
1256 Enables extended (16-bit) SPI EEPROM addressing.
1257 (symmetrical to CONFIG_I2C_X)
1261 Enables a software (bit-bang) SPI driver rather than
1262 using hardware support. This is a general purpose
1263 driver that only requires three general I/O port pins
1264 (two outputs, one input) to function. If this is
1265 defined, the board configuration must define several
1266 SPI configuration items (port pins to use, etc). For
1267 an example, see include/configs/sacsng.h.
1269 - FPGA Support: CONFIG_FPGA_COUNT
1271 Specify the number of FPGA devices to support.
1275 Used to specify the types of FPGA devices. For example,
1276 #define CONFIG_FPGA CFG_XILINX_VIRTEX2
1278 CFG_FPGA_PROG_FEEDBACK
1280 Enable printing of hash marks during FPGA configuration.
1284 Enable checks on FPGA configuration interface busy
1285 status by the configuration function. This option
1286 will require a board or device specific function to
1291 If defined, a function that provides delays in the FPGA
1292 configuration driver.
1294 CFG_FPGA_CHECK_CTRLC
1295 Allow Control-C to interrupt FPGA configuration
1297 CFG_FPGA_CHECK_ERROR
1299 Check for configuration errors during FPGA bitfile
1300 loading. For example, abort during Virtex II
1301 configuration if the INIT_B line goes low (which
1302 indicated a CRC error).
1306 Maximum time to wait for the INIT_B line to deassert
1307 after PROB_B has been deasserted during a Virtex II
1308 FPGA configuration sequence. The default time is 500
1313 Maximum time to wait for BUSY to deassert during
1314 Virtex II FPGA configuration. The default is 5 mS.
1316 CFG_FPGA_WAIT_CONFIG
1318 Time to wait after FPGA configuration. The default is
1321 - Configuration Management:
1324 If defined, this string will be added to the U-Boot
1325 version information (U_BOOT_VERSION)
1327 - Vendor Parameter Protection:
1329 U-Boot considers the values of the environment
1330 variables "serial#" (Board Serial Number) and
1331 "ethaddr" (Ethernet Address) to be parameters that
1332 are set once by the board vendor / manufacturer, and
1333 protects these variables from casual modification by
1334 the user. Once set, these variables are read-only,
1335 and write or delete attempts are rejected. You can
1336 change this behviour:
1338 If CONFIG_ENV_OVERWRITE is #defined in your config
1339 file, the write protection for vendor parameters is
1340 completely disabled. Anybody can change or delete
1343 Alternatively, if you #define _both_ CONFIG_ETHADDR
1344 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
1345 ethernet address is installed in the environment,
1346 which can be changed exactly ONCE by the user. [The
1347 serial# is unaffected by this, i. e. it remains
1353 Define this variable to enable the reservation of
1354 "protected RAM", i. e. RAM which is not overwritten
1355 by U-Boot. Define CONFIG_PRAM to hold the number of
1356 kB you want to reserve for pRAM. You can overwrite
1357 this default value by defining an environment
1358 variable "pram" to the number of kB you want to
1359 reserve. Note that the board info structure will
1360 still show the full amount of RAM. If pRAM is
1361 reserved, a new environment variable "mem" will
1362 automatically be defined to hold the amount of
1363 remaining RAM in a form that can be passed as boot
1364 argument to Linux, for instance like that:
1366 setenv bootargs ... mem=\$(mem)
1369 This way you can tell Linux not to use this memory,
1370 either, which results in a memory region that will
1371 not be affected by reboots.
1373 *WARNING* If your board configuration uses automatic
1374 detection of the RAM size, you must make sure that
1375 this memory test is non-destructive. So far, the
1376 following board configurations are known to be
1379 ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL,
1380 HERMES, IP860, RPXlite, LWMON, LANTEC,
1381 PCU_E, FLAGADM, TQM8260
1386 Define this variable to stop the system in case of a
1387 fatal error, so that you have to reset it manually.
1388 This is probably NOT a good idea for an embedded
1389 system where you want to system to reboot
1390 automatically as fast as possible, but it may be
1391 useful during development since you can try to debug
1392 the conditions that lead to the situation.
1394 CONFIG_NET_RETRY_COUNT
1396 This variable defines the number of retries for
1397 network operations like ARP, RARP, TFTP, or BOOTP
1398 before giving up the operation. If not defined, a
1399 default value of 5 is used.
1401 - Command Interpreter:
1404 Enable auto completion of commands using TAB.
1408 Define this variable to enable the "hush" shell (from
1409 Busybox) as command line interpreter, thus enabling
1410 powerful command line syntax like
1411 if...then...else...fi conditionals or `&&' and '||'
1412 constructs ("shell scripts").
1414 If undefined, you get the old, much simpler behaviour
1415 with a somewhat smaller memory footprint.
1420 This defines the secondary prompt string, which is
1421 printed when the command interpreter needs more input
1422 to complete a command. Usually "> ".
1426 In the current implementation, the local variables
1427 space and global environment variables space are
1428 separated. Local variables are those you define by
1429 simply typing `name=value'. To access a local
1430 variable later on, you have write `$name' or
1431 `${name}'; to execute the contents of a variable
1432 directly type `$name' at the command prompt.
1434 Global environment variables are those you use
1435 setenv/printenv to work with. To run a command stored
1436 in such a variable, you need to use the run command,
1437 and you must not use the '$' sign to access them.
1439 To store commands and special characters in a
1440 variable, please use double quotation marks
1441 surrounding the whole text of the variable, instead
1442 of the backslashes before semicolons and special
1445 - Default Environment:
1446 CONFIG_EXTRA_ENV_SETTINGS
1448 Define this to contain any number of null terminated
1449 strings (variable = value pairs) that will be part of
1450 the default environment compiled into the boot image.
1452 For example, place something like this in your
1453 board's config file:
1455 #define CONFIG_EXTRA_ENV_SETTINGS \
1459 Warning: This method is based on knowledge about the
1460 internal format how the environment is stored by the
1461 U-Boot code. This is NOT an official, exported
1462 interface! Although it is unlikely that this format
1463 will change soon, there is no guarantee either.
1464 You better know what you are doing here.
1466 Note: overly (ab)use of the default environment is
1467 discouraged. Make sure to check other ways to preset
1468 the environment like the autoscript function or the
1471 - DataFlash Support:
1472 CONFIG_HAS_DATAFLASH
1474 Defining this option enables DataFlash features and
1475 allows to read/write in Dataflash via the standard
1478 - SystemACE Support:
1481 Adding this option adds support for Xilinx SystemACE
1482 chips attached via some sort of local bus. The address
1483 of the chip must alsh be defined in the
1484 CFG_SYSTEMACE_BASE macro. For example:
1486 #define CONFIG_SYSTEMACE
1487 #define CFG_SYSTEMACE_BASE 0xf0000000
1489 When SystemACE support is added, the "ace" device type
1490 becomes available to the fat commands, i.e. fatls.
1492 - TFTP Fixed UDP Port:
1495 If this is defined, the environment variable tftpsrcp
1496 is used to supply the TFTP UDP source port value.
1497 If tftpsrcp isn't defined, the normal pseudo-random port
1498 number generator is used.
1500 Also, the environment variable tftpdstp is used to supply
1501 the TFTP UDP destination port value. If tftpdstp isn't
1502 defined, the normal port 69 is used.
1504 The purpose for tftpsrcp is to allow a TFTP server to
1505 blindly start the TFTP transfer using the pre-configured
1506 target IP address and UDP port. This has the effect of
1507 "punching through" the (Windows XP) firewall, allowing
1508 the remainder of the TFTP transfer to proceed normally.
1509 A better solution is to properly configure the firewall,
1510 but sometimes that is not allowed.
1512 - Show boot progress:
1513 CONFIG_SHOW_BOOT_PROGRESS
1515 Defining this option allows to add some board-
1516 specific code (calling a user-provided function
1517 "show_boot_progress(int)") that enables you to show
1518 the system's boot progress on some display (for
1519 example, some LED's) on your board. At the moment,
1520 the following checkpoints are implemented:
1523 1 common/cmd_bootm.c before attempting to boot an image
1524 -1 common/cmd_bootm.c Image header has bad magic number
1525 2 common/cmd_bootm.c Image header has correct magic number
1526 -2 common/cmd_bootm.c Image header has bad checksum
1527 3 common/cmd_bootm.c Image header has correct checksum
1528 -3 common/cmd_bootm.c Image data has bad checksum
1529 4 common/cmd_bootm.c Image data has correct checksum
1530 -4 common/cmd_bootm.c Image is for unsupported architecture
1531 5 common/cmd_bootm.c Architecture check OK
1532 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi, standalone)
1533 6 common/cmd_bootm.c Image Type check OK
1534 -6 common/cmd_bootm.c gunzip uncompression error
1535 -7 common/cmd_bootm.c Unimplemented compression type
1536 7 common/cmd_bootm.c Uncompression OK
1537 -8 common/cmd_bootm.c Wrong Image Type (not kernel, multi, standalone)
1538 8 common/cmd_bootm.c Image Type check OK
1539 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
1540 9 common/cmd_bootm.c Start initial ramdisk verification
1541 -10 common/cmd_bootm.c Ramdisk header has bad magic number
1542 -11 common/cmd_bootm.c Ramdisk header has bad checksum
1543 10 common/cmd_bootm.c Ramdisk header is OK
1544 -12 common/cmd_bootm.c Ramdisk data has bad checksum
1545 11 common/cmd_bootm.c Ramdisk data has correct checksum
1546 12 common/cmd_bootm.c Ramdisk verification complete, start loading
1547 -13 common/cmd_bootm.c Wrong Image Type (not PPC Linux Ramdisk)
1548 13 common/cmd_bootm.c Start multifile image verification
1549 14 common/cmd_bootm.c No initial ramdisk, no multifile, continue.
1550 15 common/cmd_bootm.c All preparation done, transferring control to OS
1552 -30 lib_ppc/board.c Fatal error, hang the system
1553 -31 post/post.c POST test failed, detected by post_output_backlog()
1554 -32 post/post.c POST test failed, detected by post_run_single()
1556 -1 common/cmd_doc.c Bad usage of "doc" command
1557 -1 common/cmd_doc.c No boot device
1558 -1 common/cmd_doc.c Unknown Chip ID on boot device
1559 -1 common/cmd_doc.c Read Error on boot device
1560 -1 common/cmd_doc.c Image header has bad magic number
1562 -1 common/cmd_ide.c Bad usage of "ide" command
1563 -1 common/cmd_ide.c No boot device
1564 -1 common/cmd_ide.c Unknown boot device
1565 -1 common/cmd_ide.c Unknown partition table
1566 -1 common/cmd_ide.c Invalid partition type
1567 -1 common/cmd_ide.c Read Error on boot device
1568 -1 common/cmd_ide.c Image header has bad magic number
1570 -1 common/cmd_nand.c Bad usage of "nand" command
1571 -1 common/cmd_nand.c No boot device
1572 -1 common/cmd_nand.c Unknown Chip ID on boot device
1573 -1 common/cmd_nand.c Read Error on boot device
1574 -1 common/cmd_nand.c Image header has bad magic number
1576 -1 common/env_common.c Environment has a bad CRC, using default
1582 [so far only for SMDK2400 and TRAB boards]
1584 - Modem support endable:
1585 CONFIG_MODEM_SUPPORT
1587 - RTS/CTS Flow control enable:
1590 - Modem debug support:
1591 CONFIG_MODEM_SUPPORT_DEBUG
1593 Enables debugging stuff (char screen[1024], dbg())
1594 for modem support. Useful only with BDI2000.
1596 - Interrupt support (PPC):
1598 There are common interrupt_init() and timer_interrupt()
1599 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
1600 for cpu specific initialization. interrupt_init_cpu()
1601 should set decrementer_count to appropriate value. If
1602 cpu resets decrementer automatically after interrupt
1603 (ppc4xx) it should set decrementer_count to zero.
1604 timer_interrupt() calls timer_interrupt_cpu() for cpu
1605 specific handling. If board has watchdog / status_led
1606 / other_activity_monitor it works automatically from
1607 general timer_interrupt().
1611 In the target system modem support is enabled when a
1612 specific key (key combination) is pressed during
1613 power-on. Otherwise U-Boot will boot normally
1614 (autoboot). The key_pressed() fuction is called from
1615 board_init(). Currently key_pressed() is a dummy
1616 function, returning 1 and thus enabling modem
1619 If there are no modem init strings in the
1620 environment, U-Boot proceed to autoboot; the
1621 previous output (banner, info printfs) will be
1624 See also: doc/README.Modem
1627 Configuration Settings:
1628 -----------------------
1630 - CFG_LONGHELP: Defined when you want long help messages included;
1631 undefine this when you're short of memory.
1633 - CFG_PROMPT: This is what U-Boot prints on the console to
1634 prompt for user input.
1636 - CFG_CBSIZE: Buffer size for input from the Console
1638 - CFG_PBSIZE: Buffer size for Console output
1640 - CFG_MAXARGS: max. Number of arguments accepted for monitor commands
1642 - CFG_BARGSIZE: Buffer size for Boot Arguments which are passed to
1643 the application (usually a Linux kernel) when it is
1646 - CFG_BAUDRATE_TABLE:
1647 List of legal baudrate settings for this board.
1649 - CFG_CONSOLE_INFO_QUIET
1650 Suppress display of console information at boot.
1652 - CFG_CONSOLE_IS_IN_ENV
1653 If the board specific function
1654 extern int overwrite_console (void);
1655 returns 1, the stdin, stderr and stdout are switched to the
1656 serial port, else the settings in the environment are used.
1658 - CFG_CONSOLE_OVERWRITE_ROUTINE
1659 Enable the call to overwrite_console().
1661 - CFG_CONSOLE_ENV_OVERWRITE
1662 Enable overwrite of previous console environment settings.
1664 - CFG_MEMTEST_START, CFG_MEMTEST_END:
1665 Begin and End addresses of the area used by the
1669 Enable an alternate, more extensive memory test.
1671 - CFG_MEMTEST_SCRATCH:
1672 Scratch address used by the alternate memory test
1673 You only need to set this if address zero isn't writeable
1675 - CFG_TFTP_LOADADDR:
1676 Default load address for network file downloads
1678 - CFG_LOADS_BAUD_CHANGE:
1679 Enable temporary baudrate change while serial download
1682 Physical start address of SDRAM. _Must_ be 0 here.
1685 Physical start address of Motherboard I/O (if using a
1689 Physical start address of Flash memory.
1692 Physical start address of boot monitor code (set by
1693 make config files to be same as the text base address
1694 (TEXT_BASE) used when linking) - same as
1695 CFG_FLASH_BASE when booting from flash.
1698 Size of memory reserved for monitor code, used to
1699 determine _at_compile_time_ (!) if the environment is
1700 embedded within the U-Boot image, or in a separate
1704 Size of DRAM reserved for malloc() use.
1707 Maximum size of memory mapped by the startup code of
1708 the Linux kernel; all data that must be processed by
1709 the Linux kernel (bd_info, boot arguments, eventually
1710 initrd image) must be put below this limit.
1712 - CFG_MAX_FLASH_BANKS:
1713 Max number of Flash memory banks
1715 - CFG_MAX_FLASH_SECT:
1716 Max number of sectors on a Flash chip
1718 - CFG_FLASH_ERASE_TOUT:
1719 Timeout for Flash erase operations (in ms)
1721 - CFG_FLASH_WRITE_TOUT:
1722 Timeout for Flash write operations (in ms)
1724 - CFG_FLASH_LOCK_TOUT
1725 Timeout for Flash set sector lock bit operation (in ms)
1727 - CFG_FLASH_UNLOCK_TOUT
1728 Timeout for Flash clear lock bits operation (in ms)
1730 - CFG_FLASH_PROTECTION
1731 If defined, hardware flash sectors protection is used
1732 instead of U-Boot software protection.
1734 - CFG_DIRECT_FLASH_TFTP:
1736 Enable TFTP transfers directly to flash memory;
1737 without this option such a download has to be
1738 performed in two steps: (1) download to RAM, and (2)
1739 copy from RAM to flash.
1741 The two-step approach is usually more reliable, since
1742 you can check if the download worked before you erase
1743 the flash, but in some situations (when sytem RAM is
1744 too limited to allow for a tempory copy of the
1745 downloaded image) this option may be very useful.
1748 Define if the flash driver uses extra elements in the
1749 common flash structure for storing flash geometry.
1751 - CFG_FLASH_CFI_DRIVER
1752 This option also enables the building of the cfi_flash driver
1753 in the drivers directory
1755 - CFG_RX_ETH_BUFFER:
1756 Defines the number of ethernet receive buffers. On some
1757 ethernet controllers it is recommended to set this value
1758 to 8 or even higher (EEPRO100 or 405 EMAC), since all
1759 buffers can be full shortly after enabling the interface
1760 on high ethernet traffic.
1761 Defaults to 4 if not defined.
1763 The following definitions that deal with the placement and management
1764 of environment data (variable area); in general, we support the
1765 following configurations:
1767 - CFG_ENV_IS_IN_FLASH:
1769 Define this if the environment is in flash memory.
1771 a) The environment occupies one whole flash sector, which is
1772 "embedded" in the text segment with the U-Boot code. This
1773 happens usually with "bottom boot sector" or "top boot
1774 sector" type flash chips, which have several smaller
1775 sectors at the start or the end. For instance, such a
1776 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
1777 such a case you would place the environment in one of the
1778 4 kB sectors - with U-Boot code before and after it. With
1779 "top boot sector" type flash chips, you would put the
1780 environment in one of the last sectors, leaving a gap
1781 between U-Boot and the environment.
1785 Offset of environment data (variable area) to the
1786 beginning of flash memory; for instance, with bottom boot
1787 type flash chips the second sector can be used: the offset
1788 for this sector is given here.
1790 CFG_ENV_OFFSET is used relative to CFG_FLASH_BASE.
1794 This is just another way to specify the start address of
1795 the flash sector containing the environment (instead of
1798 - CFG_ENV_SECT_SIZE:
1800 Size of the sector containing the environment.
1803 b) Sometimes flash chips have few, equal sized, BIG sectors.
1804 In such a case you don't want to spend a whole sector for
1809 If you use this in combination with CFG_ENV_IS_IN_FLASH
1810 and CFG_ENV_SECT_SIZE, you can specify to use only a part
1811 of this flash sector for the environment. This saves
1812 memory for the RAM copy of the environment.
1814 It may also save flash memory if you decide to use this
1815 when your environment is "embedded" within U-Boot code,
1816 since then the remainder of the flash sector could be used
1817 for U-Boot code. It should be pointed out that this is
1818 STRONGLY DISCOURAGED from a robustness point of view:
1819 updating the environment in flash makes it always
1820 necessary to erase the WHOLE sector. If something goes
1821 wrong before the contents has been restored from a copy in
1822 RAM, your target system will be dead.
1824 - CFG_ENV_ADDR_REDUND
1827 These settings describe a second storage area used to hold
1828 a redundand copy of the environment data, so that there is
1829 a valid backup copy in case there is a power failure during
1830 a "saveenv" operation.
1832 BE CAREFUL! Any changes to the flash layout, and some changes to the
1833 source code will make it necessary to adapt <board>/u-boot.lds*
1837 - CFG_ENV_IS_IN_NVRAM:
1839 Define this if you have some non-volatile memory device
1840 (NVRAM, battery buffered SRAM) which you want to use for the
1846 These two #defines are used to determin the memory area you
1847 want to use for environment. It is assumed that this memory
1848 can just be read and written to, without any special
1851 BE CAREFUL! The first access to the environment happens quite early
1852 in U-Boot initalization (when we try to get the setting of for the
1853 console baudrate). You *MUST* have mappend your NVRAM area then, or
1856 Please note that even with NVRAM we still use a copy of the
1857 environment in RAM: we could work on NVRAM directly, but we want to
1858 keep settings there always unmodified except somebody uses "saveenv"
1859 to save the current settings.
1862 - CFG_ENV_IS_IN_EEPROM:
1864 Use this if you have an EEPROM or similar serial access
1865 device and a driver for it.
1870 These two #defines specify the offset and size of the
1871 environment area within the total memory of your EEPROM.
1873 - CFG_I2C_EEPROM_ADDR:
1874 If defined, specified the chip address of the EEPROM device.
1875 The default address is zero.
1877 - CFG_EEPROM_PAGE_WRITE_BITS:
1878 If defined, the number of bits used to address bytes in a
1879 single page in the EEPROM device. A 64 byte page, for example
1880 would require six bits.
1882 - CFG_EEPROM_PAGE_WRITE_DELAY_MS:
1883 If defined, the number of milliseconds to delay between
1884 page writes. The default is zero milliseconds.
1886 - CFG_I2C_EEPROM_ADDR_LEN:
1887 The length in bytes of the EEPROM memory array address. Note
1888 that this is NOT the chip address length!
1890 - CFG_I2C_EEPROM_ADDR_OVERFLOW:
1891 EEPROM chips that implement "address overflow" are ones
1892 like Catalyst 24WC04/08/16 which has 9/10/11 bits of
1893 address and the extra bits end up in the "chip address" bit
1894 slots. This makes a 24WC08 (1Kbyte) chip look like four 256
1897 Note that we consider the length of the address field to
1898 still be one byte because the extra address bits are hidden
1899 in the chip address.
1902 The size in bytes of the EEPROM device.
1905 - CFG_ENV_IS_IN_DATAFLASH:
1907 Define this if you have a DataFlash memory device which you
1908 want to use for the environment.
1914 These three #defines specify the offset and size of the
1915 environment area within the total memory of your DataFlash placed
1916 at the specified address.
1918 - CFG_ENV_IS_IN_NAND:
1920 Define this if you have a NAND device which you want to use
1921 for the environment.
1926 These two #defines specify the offset and size of the environment
1927 area within the first NAND device.
1929 - CFG_SPI_INIT_OFFSET
1931 Defines offset to the initial SPI buffer area in DPRAM. The
1932 area is used at an early stage (ROM part) if the environment
1933 is configured to reside in the SPI EEPROM: We need a 520 byte
1934 scratch DPRAM area. It is used between the two initialization
1935 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
1936 to be a good choice since it makes it far enough from the
1937 start of the data area as well as from the stack pointer.
1939 Please note that the environment is read-only as long as the monitor
1940 has been relocated to RAM and a RAM copy of the environment has been
1941 created; also, when using EEPROM you will have to use getenv_r()
1942 until then to read environment variables.
1944 The environment is protected by a CRC32 checksum. Before the monitor
1945 is relocated into RAM, as a result of a bad CRC you will be working
1946 with the compiled-in default environment - *silently*!!! [This is
1947 necessary, because the first environment variable we need is the
1948 "baudrate" setting for the console - if we have a bad CRC, we don't
1949 have any device yet where we could complain.]
1951 Note: once the monitor has been relocated, then it will complain if
1952 the default environment is used; a new CRC is computed as soon as you
1953 use the "saveenv" command to store a valid environment.
1955 - CFG_FAULT_ECHO_LINK_DOWN:
1956 Echo the inverted Ethernet link state to the fault LED.
1958 Note: If this option is active, then CFG_FAULT_MII_ADDR
1959 also needs to be defined.
1961 - CFG_FAULT_MII_ADDR:
1962 MII address of the PHY to check for the Ethernet link state.
1964 - CFG_64BIT_VSPRINTF:
1965 Makes vsprintf (and all *printf functions) support printing
1966 of 64bit values by using the L quantifier
1968 - CFG_64BIT_STRTOUL:
1969 Adds simple_strtoull that returns a 64bit value
1971 Low Level (hardware related) configuration options:
1972 ---------------------------------------------------
1974 - CFG_CACHELINE_SIZE:
1975 Cache Line Size of the CPU.
1978 Default address of the IMMR after system reset.
1980 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
1981 and RPXsuper) to be able to adjust the position of
1982 the IMMR register after a reset.
1984 - Floppy Disk Support:
1985 CFG_FDC_DRIVE_NUMBER
1987 the default drive number (default value 0)
1991 defines the spacing between fdc chipset registers
1996 defines the offset of register from address. It
1997 depends on which part of the data bus is connected to
1998 the fdc chipset. (default value 0)
2000 If CFG_ISA_IO_STRIDE CFG_ISA_IO_OFFSET and
2001 CFG_FDC_DRIVE_NUMBER are undefined, they take their
2004 if CFG_FDC_HW_INIT is defined, then the function
2005 fdc_hw_init() is called at the beginning of the FDC
2006 setup. fdc_hw_init() must be provided by the board
2007 source code. It is used to make hardware dependant
2010 - CFG_IMMR: Physical address of the Internal Memory.
2011 DO NOT CHANGE unless you know exactly what you're
2012 doing! (11-4) [MPC8xx/82xx systems only]
2014 - CFG_INIT_RAM_ADDR:
2016 Start address of memory area that can be used for
2017 initial data and stack; please note that this must be
2018 writable memory that is working WITHOUT special
2019 initialization, i. e. you CANNOT use normal RAM which
2020 will become available only after programming the
2021 memory controller and running certain initialization
2024 U-Boot uses the following memory types:
2025 - MPC8xx and MPC8260: IMMR (internal memory of the CPU)
2026 - MPC824X: data cache
2027 - PPC4xx: data cache
2029 - CFG_GBL_DATA_OFFSET:
2031 Offset of the initial data structure in the memory
2032 area defined by CFG_INIT_RAM_ADDR. Usually
2033 CFG_GBL_DATA_OFFSET is chosen such that the initial
2034 data is located at the end of the available space
2035 (sometimes written as (CFG_INIT_RAM_END -
2036 CFG_INIT_DATA_SIZE), and the initial stack is just
2037 below that area (growing from (CFG_INIT_RAM_ADDR +
2038 CFG_GBL_DATA_OFFSET) downward.
2041 On the MPC824X (or other systems that use the data
2042 cache for initial memory) the address chosen for
2043 CFG_INIT_RAM_ADDR is basically arbitrary - it must
2044 point to an otherwise UNUSED address space between
2045 the top of RAM and the start of the PCI space.
2047 - CFG_SIUMCR: SIU Module Configuration (11-6)
2049 - CFG_SYPCR: System Protection Control (11-9)
2051 - CFG_TBSCR: Time Base Status and Control (11-26)
2053 - CFG_PISCR: Periodic Interrupt Status and Control (11-31)
2055 - CFG_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30)
2057 - CFG_SCCR: System Clock and reset Control Register (15-27)
2059 - CFG_OR_TIMING_SDRAM:
2063 periodic timer for refresh
2065 - CFG_DER: Debug Event Register (37-47)
2067 - FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CFG_REMAP_OR_AM,
2068 CFG_PRELIM_OR_AM, CFG_OR_TIMING_FLASH, CFG_OR0_REMAP,
2069 CFG_OR0_PRELIM, CFG_BR0_PRELIM, CFG_OR1_REMAP, CFG_OR1_PRELIM,
2071 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
2073 - SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
2074 CFG_OR_TIMING_SDRAM, CFG_OR2_PRELIM, CFG_BR2_PRELIM,
2075 CFG_OR3_PRELIM, CFG_BR3_PRELIM:
2076 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
2078 - CFG_MAMR_PTA, CFG_MPTPR_2BK_4K, CFG_MPTPR_1BK_4K, CFG_MPTPR_2BK_8K,
2079 CFG_MPTPR_1BK_8K, CFG_MAMR_8COL, CFG_MAMR_9COL:
2080 Machine Mode Register and Memory Periodic Timer
2081 Prescaler definitions (SDRAM timing)
2083 - CFG_I2C_UCODE_PATCH, CFG_I2C_DPMEM_OFFSET [0x1FC0]:
2084 enable I2C microcode relocation patch (MPC8xx);
2085 define relocation offset in DPRAM [DSP2]
2087 - CFG_SPI_UCODE_PATCH, CFG_SPI_DPMEM_OFFSET [0x1FC0]:
2088 enable SPI microcode relocation patch (MPC8xx);
2089 define relocation offset in DPRAM [SCC4]
2092 Use OSCM clock mode on MBX8xx board. Be careful,
2093 wrong setting might damage your board. Read
2094 doc/README.MBX before setting this variable!
2096 - CFG_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
2097 Offset of the bootmode word in DPRAM used by post
2098 (Power On Self Tests). This definition overrides
2099 #define'd default value in commproc.h resp.
2102 - CFG_PCI_SLV_MEM_LOCAL, CFG_PCI_SLV_MEM_BUS, CFG_PICMR0_MASK_ATTRIB,
2103 CFG_PCI_MSTR0_LOCAL, CFG_PCIMSK0_MASK, CFG_PCI_MSTR1_LOCAL,
2104 CFG_PCIMSK1_MASK, CFG_PCI_MSTR_MEM_LOCAL, CFG_PCI_MSTR_MEM_BUS,
2105 CFG_CPU_PCI_MEM_START, CFG_PCI_MSTR_MEM_SIZE, CFG_POCMR0_MASK_ATTRIB,
2106 CFG_PCI_MSTR_MEMIO_LOCAL, CFG_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
2107 CFG_PCI_MSTR_MEMIO_SIZE, CFG_POCMR1_MASK_ATTRIB, CFG_PCI_MSTR_IO_LOCAL,
2108 CFG_PCI_MSTR_IO_BUS, CFG_CPU_PCI_IO_START, CFG_PCI_MSTR_IO_SIZE,
2109 CFG_POCMR2_MASK_ATTRIB: (MPC826x only)
2110 Overrides the default PCI memory map in cpu/mpc8260/pci.c if set.
2112 - CONFIG_ETHER_ON_FEC[12]
2113 Define to enable FEC[12] on a 8xx series processor.
2115 - CONFIG_FEC[12]_PHY
2116 Define to the hardcoded PHY address which corresponds
2117 to the given FEC; i. e.
2118 #define CONFIG_FEC1_PHY 4
2119 means that the PHY with address 4 is connected to FEC1
2121 When set to -1, means to probe for first available.
2123 - CONFIG_FEC[12]_PHY_NORXERR
2124 The PHY does not have a RXERR line (RMII only).
2125 (so program the FEC to ignore it).
2128 Enable RMII mode for all FECs.
2129 Note that this is a global option, we can't
2130 have one FEC in standard MII mode and another in RMII mode.
2132 - CONFIG_CRC32_VERIFY
2133 Add a verify option to the crc32 command.
2136 => crc32 -v <address> <count> <crc32>
2138 Where address/count indicate a memory area
2139 and crc32 is the correct crc32 which the
2143 Add the "loopw" memory command. This only takes effect if
2144 the memory commands are activated globally (CFG_CMD_MEM).
2147 Add the "mdc" and "mwc" memory commands. These are cyclic
2152 This command will print 4 bytes (10,11,12,13) each 500 ms.
2154 => mwc.l 100 12345678 10
2155 This command will write 12345678 to address 100 all 10 ms.
2157 This only takes effect if the memory commands are activated
2158 globally (CFG_CMD_MEM).
2160 - CONFIG_SKIP_LOWLEVEL_INIT
2161 - CONFIG_SKIP_RELOCATE_UBOOT
2163 [ARM only] If these variables are defined, then
2164 certain low level initializations (like setting up
2165 the memory controller) are omitted and/or U-Boot does
2166 not relocate itself into RAM.
2167 Normally these variables MUST NOT be defined. The
2168 only exception is when U-Boot is loaded (to RAM) by
2169 some other boot loader or by a debugger which
2170 performs these intializations itself.
2173 Building the Software:
2174 ======================
2176 Building U-Boot has been tested in native PPC environments (on a
2177 PowerBook G3 running LinuxPPC 2000) and in cross environments
2178 (running RedHat 6.x and 7.x Linux on x86, Solaris 2.6 on a SPARC, and
2181 If you are not using a native PPC environment, it is assumed that you
2182 have the GNU cross compiling tools available in your path and named
2183 with a prefix of "powerpc-linux-". If this is not the case, (e.g. if
2184 you are using Monta Vista's Hard Hat Linux CDK 1.2) you must change
2185 the definition of CROSS_COMPILE in Makefile. For HHL on a 4xx CPU,
2188 CROSS_COMPILE = ppc_4xx-
2191 U-Boot is intended to be simple to build. After installing the
2192 sources you must configure U-Boot for one specific board type. This
2197 where "NAME_config" is the name of one of the existing
2198 configurations; the following names are supported:
2200 ADCIOP_config FPS860L_config omap730p2_config
2201 ADS860_config GEN860T_config pcu_e_config
2203 AR405_config GENIETV_config PIP405_config
2204 at91rm9200dk_config GTH_config QS823_config
2205 CANBT_config hermes_config QS850_config
2206 cmi_mpc5xx_config hymod_config QS860T_config
2207 cogent_common_config IP860_config RPXlite_config
2208 cogent_mpc8260_config IVML24_config RPXlite_DW_config
2209 cogent_mpc8xx_config IVMS8_config RPXsuper_config
2210 CPCI405_config JSE_config rsdproto_config
2211 CPCIISER4_config LANTEC_config Sandpoint8240_config
2212 csb272_config lwmon_config sbc8260_config
2213 CU824_config MBX860T_config sbc8560_33_config
2214 DUET_ADS_config MBX_config sbc8560_66_config
2215 EBONY_config MPC8260ADS_config SM850_config
2216 ELPT860_config MPC8540ADS_config SPD823TS_config
2217 ESTEEM192E_config MPC8540EVAL_config stxgp3_config
2218 ETX094_config MPC8560ADS_config SXNI855T_config
2219 FADS823_config NETVIA_config TQM823L_config
2220 FADS850SAR_config omap1510inn_config TQM850L_config
2221 FADS860T_config omap1610h2_config TQM855L_config
2222 FPS850L_config omap1610inn_config TQM860L_config
2223 omap5912osk_config walnut_config
2224 omap2420h4_config Yukon8220_config
2227 Note: for some board special configuration names may exist; check if
2228 additional information is available from the board vendor; for
2229 instance, the TQM823L systems are available without (standard)
2230 or with LCD support. You can select such additional "features"
2231 when chosing the configuration, i. e.
2234 - will configure for a plain TQM823L, i. e. no LCD support
2236 make TQM823L_LCD_config
2237 - will configure for a TQM823L with U-Boot console on LCD
2242 Finally, type "make all", and you should get some working U-Boot
2243 images ready for download to / installation on your system:
2245 - "u-boot.bin" is a raw binary image
2246 - "u-boot" is an image in ELF binary format
2247 - "u-boot.srec" is in Motorola S-Record format
2250 Please be aware that the Makefiles assume you are using GNU make, so
2251 for instance on NetBSD you might need to use "gmake" instead of
2255 If the system board that you have is not listed, then you will need
2256 to port U-Boot to your hardware platform. To do this, follow these
2259 1. Add a new configuration option for your board to the toplevel
2260 "Makefile" and to the "MAKEALL" script, using the existing
2261 entries as examples. Note that here and at many other places
2262 boards and other names are listed in alphabetical sort order. Please
2264 2. Create a new directory to hold your board specific code. Add any
2265 files you need. In your board directory, you will need at least
2266 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
2267 3. Create a new configuration file "include/configs/<board>.h" for
2269 3. If you're porting U-Boot to a new CPU, then also create a new
2270 directory to hold your CPU specific code. Add any files you need.
2271 4. Run "make <board>_config" with your new name.
2272 5. Type "make", and you should get a working "u-boot.srec" file
2273 to be installed on your target system.
2274 6. Debug and solve any problems that might arise.
2275 [Of course, this last step is much harder than it sounds.]
2278 Testing of U-Boot Modifications, Ports to New Hardware, etc.:
2279 ==============================================================
2281 If you have modified U-Boot sources (for instance added a new board
2282 or support for new devices, a new CPU, etc.) you are expected to
2283 provide feedback to the other developers. The feedback normally takes
2284 the form of a "patch", i. e. a context diff against a certain (latest
2285 official or latest in CVS) version of U-Boot sources.
2287 But before you submit such a patch, please verify that your modifi-
2288 cation did not break existing code. At least make sure that *ALL* of
2289 the supported boards compile WITHOUT ANY compiler warnings. To do so,
2290 just run the "MAKEALL" script, which will configure and build U-Boot
2291 for ALL supported system. Be warned, this will take a while. You can
2292 select which (cross) compiler to use by passing a `CROSS_COMPILE'
2293 environment variable to the script, i. e. to use the cross tools from
2294 MontaVista's Hard Hat Linux you can type
2296 CROSS_COMPILE=ppc_8xx- MAKEALL
2298 or to build on a native PowerPC system you can type
2300 CROSS_COMPILE=' ' MAKEALL
2302 See also "U-Boot Porting Guide" below.
2305 Monitor Commands - Overview:
2306 ============================
2308 go - start application at address 'addr'
2309 run - run commands in an environment variable
2310 bootm - boot application image from memory
2311 bootp - boot image via network using BootP/TFTP protocol
2312 tftpboot- boot image via network using TFTP protocol
2313 and env variables "ipaddr" and "serverip"
2314 (and eventually "gatewayip")
2315 rarpboot- boot image via network using RARP/TFTP protocol
2316 diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
2317 loads - load S-Record file over serial line
2318 loadb - load binary file over serial line (kermit mode)
2320 mm - memory modify (auto-incrementing)
2321 nm - memory modify (constant address)
2322 mw - memory write (fill)
2324 cmp - memory compare
2325 crc32 - checksum calculation
2326 imd - i2c memory display
2327 imm - i2c memory modify (auto-incrementing)
2328 inm - i2c memory modify (constant address)
2329 imw - i2c memory write (fill)
2330 icrc32 - i2c checksum calculation
2331 iprobe - probe to discover valid I2C chip addresses
2332 iloop - infinite loop on address range
2333 isdram - print SDRAM configuration information
2334 sspi - SPI utility commands
2335 base - print or set address offset
2336 printenv- print environment variables
2337 setenv - set environment variables
2338 saveenv - save environment variables to persistent storage
2339 protect - enable or disable FLASH write protection
2340 erase - erase FLASH memory
2341 flinfo - print FLASH memory information
2342 bdinfo - print Board Info structure
2343 iminfo - print header information for application image
2344 coninfo - print console devices and informations
2345 ide - IDE sub-system
2346 loop - infinite loop on address range
2347 loopw - infinite write loop on address range
2348 mtest - simple RAM test
2349 icache - enable or disable instruction cache
2350 dcache - enable or disable data cache
2351 reset - Perform RESET of the CPU
2352 echo - echo args to console
2353 version - print monitor version
2354 help - print online help
2355 ? - alias for 'help'
2358 Monitor Commands - Detailed Description:
2359 ========================================
2363 For now: just type "help <command>".
2366 Environment Variables:
2367 ======================
2369 U-Boot supports user configuration using Environment Variables which
2370 can be made persistent by saving to Flash memory.
2372 Environment Variables are set using "setenv", printed using
2373 "printenv", and saved to Flash using "saveenv". Using "setenv"
2374 without a value can be used to delete a variable from the
2375 environment. As long as you don't save the environment you are
2376 working with an in-memory copy. In case the Flash area containing the
2377 environment is erased by accident, a default environment is provided.
2379 Some configuration options can be set using Environment Variables:
2381 baudrate - see CONFIG_BAUDRATE
2383 bootdelay - see CONFIG_BOOTDELAY
2385 bootcmd - see CONFIG_BOOTCOMMAND
2387 bootargs - Boot arguments when booting an RTOS image
2389 bootfile - Name of the image to load with TFTP
2391 autoload - if set to "no" (any string beginning with 'n'),
2392 "bootp" will just load perform a lookup of the
2393 configuration from the BOOTP server, but not try to
2394 load any image using TFTP
2396 autostart - if set to "yes", an image loaded using the "bootp",
2397 "rarpboot", "tftpboot" or "diskboot" commands will
2398 be automatically started (by internally calling
2401 If set to "no", a standalone image passed to the
2402 "bootm" command will be copied to the load address
2403 (and eventually uncompressed), but NOT be started.
2404 This can be used to load and uncompress arbitrary
2407 i2cfast - (PPC405GP|PPC405EP only)
2408 if set to 'y' configures Linux I2C driver for fast
2409 mode (400kHZ). This environment variable is used in
2410 initialization code. So, for changes to be effective
2411 it must be saved and board must be reset.
2413 initrd_high - restrict positioning of initrd images:
2414 If this variable is not set, initrd images will be
2415 copied to the highest possible address in RAM; this
2416 is usually what you want since it allows for
2417 maximum initrd size. If for some reason you want to
2418 make sure that the initrd image is loaded below the
2419 CFG_BOOTMAPSZ limit, you can set this environment
2420 variable to a value of "no" or "off" or "0".
2421 Alternatively, you can set it to a maximum upper
2422 address to use (U-Boot will still check that it
2423 does not overwrite the U-Boot stack and data).
2425 For instance, when you have a system with 16 MB
2426 RAM, and want to reserve 4 MB from use by Linux,
2427 you can do this by adding "mem=12M" to the value of
2428 the "bootargs" variable. However, now you must make
2429 sure that the initrd image is placed in the first
2430 12 MB as well - this can be done with
2432 setenv initrd_high 00c00000
2434 If you set initrd_high to 0xFFFFFFFF, this is an
2435 indication to U-Boot that all addresses are legal
2436 for the Linux kernel, including addresses in flash
2437 memory. In this case U-Boot will NOT COPY the
2438 ramdisk at all. This may be useful to reduce the
2439 boot time on your system, but requires that this
2440 feature is supported by your Linux kernel.
2442 ipaddr - IP address; needed for tftpboot command
2444 loadaddr - Default load address for commands like "bootp",
2445 "rarpboot", "tftpboot", "loadb" or "diskboot"
2447 loads_echo - see CONFIG_LOADS_ECHO
2449 serverip - TFTP server IP address; needed for tftpboot command
2451 bootretry - see CONFIG_BOOT_RETRY_TIME
2453 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
2455 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
2457 ethprime - When CONFIG_NET_MULTI is enabled controls which
2458 interface is used first.
2460 ethact - When CONFIG_NET_MULTI is enabled controls which
2461 interface is currently active. For example you
2462 can do the following
2464 => setenv ethact FEC ETHERNET
2465 => ping 192.168.0.1 # traffic sent on FEC ETHERNET
2466 => setenv ethact SCC ETHERNET
2467 => ping 10.0.0.1 # traffic sent on SCC ETHERNET
2469 netretry - When set to "no" each network operation will
2470 either succeed or fail without retrying.
2471 When set to "once" the network operation will
2472 fail when all the available network interfaces
2473 are tried once without success.
2474 Useful on scripts which control the retry operation
2477 tftpsrcport - If this is set, the value is used for TFTP's
2480 tftpdstport - If this is set, the value is used for TFTP's UDP
2481 destination port instead of the Well Know Port 69.
2483 vlan - When set to a value < 4095 the traffic over
2484 ethernet is encapsulated/received over 802.1q
2487 The following environment variables may be used and automatically
2488 updated by the network boot commands ("bootp" and "rarpboot"),
2489 depending the information provided by your boot server:
2491 bootfile - see above
2492 dnsip - IP address of your Domain Name Server
2493 dnsip2 - IP address of your secondary Domain Name Server
2494 gatewayip - IP address of the Gateway (Router) to use
2495 hostname - Target hostname
2497 netmask - Subnet Mask
2498 rootpath - Pathname of the root filesystem on the NFS server
2499 serverip - see above
2502 There are two special Environment Variables:
2504 serial# - contains hardware identification information such
2505 as type string and/or serial number
2506 ethaddr - Ethernet address
2508 These variables can be set only once (usually during manufacturing of
2509 the board). U-Boot refuses to delete or overwrite these variables
2510 once they have been set once.
2513 Further special Environment Variables:
2515 ver - Contains the U-Boot version string as printed
2516 with the "version" command. This variable is
2517 readonly (see CONFIG_VERSION_VARIABLE).
2520 Please note that changes to some configuration parameters may take
2521 only effect after the next boot (yes, that's just like Windoze :-).
2524 Command Line Parsing:
2525 =====================
2527 There are two different command line parsers available with U-Boot:
2528 the old "simple" one, and the much more powerful "hush" shell:
2530 Old, simple command line parser:
2531 --------------------------------
2533 - supports environment variables (through setenv / saveenv commands)
2534 - several commands on one line, separated by ';'
2535 - variable substitution using "... $(name) ..." syntax
2536 - special characters ('$', ';') can be escaped by prefixing with '\',
2538 setenv bootcmd bootm \$(address)
2539 - You can also escape text by enclosing in single apostrophes, for example:
2540 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
2545 - similar to Bourne shell, with control structures like
2546 if...then...else...fi, for...do...done; while...do...done,
2547 until...do...done, ...
2548 - supports environment ("global") variables (through setenv / saveenv
2549 commands) and local shell variables (through standard shell syntax
2550 "name=value"); only environment variables can be used with "run"
2556 (1) If a command line (or an environment variable executed by a "run"
2557 command) contains several commands separated by semicolon, and
2558 one of these commands fails, then the remaining commands will be
2561 (2) If you execute several variables with one call to run (i. e.
2562 calling run with a list af variables as arguments), any failing
2563 command will cause "run" to terminate, i. e. the remaining
2564 variables are not executed.
2566 Note for Redundant Ethernet Interfaces:
2567 =======================================
2569 Some boards come with redundant ethernet interfaces; U-Boot supports
2570 such configurations and is capable of automatic selection of a
2571 "working" interface when needed. MAC assignment works as follows:
2573 Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
2574 MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
2575 "eth1addr" (=>eth1), "eth2addr", ...
2577 If the network interface stores some valid MAC address (for instance
2578 in SROM), this is used as default address if there is NO correspon-
2579 ding setting in the environment; if the corresponding environment
2580 variable is set, this overrides the settings in the card; that means:
2582 o If the SROM has a valid MAC address, and there is no address in the
2583 environment, the SROM's address is used.
2585 o If there is no valid address in the SROM, and a definition in the
2586 environment exists, then the value from the environment variable is
2589 o If both the SROM and the environment contain a MAC address, and
2590 both addresses are the same, this MAC address is used.
2592 o If both the SROM and the environment contain a MAC address, and the
2593 addresses differ, the value from the environment is used and a
2596 o If neither SROM nor the environment contain a MAC address, an error
2603 The "boot" commands of this monitor operate on "image" files which
2604 can be basicly anything, preceeded by a special header; see the
2605 definitions in include/image.h for details; basicly, the header
2606 defines the following image properties:
2608 * Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
2609 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
2610 LynxOS, pSOS, QNX, RTEMS, ARTOS;
2611 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, ARTOS, LynxOS).
2612 * Target CPU Architecture (Provisions for Alpha, ARM, Intel x86,
2613 IA64, MIPS, NIOS, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
2614 Currently supported: ARM, Intel x86, MIPS, NIOS, PowerPC).
2615 * Compression Type (uncompressed, gzip, bzip2)
2621 The header is marked by a special Magic Number, and both the header
2622 and the data portions of the image are secured against corruption by
2629 Although U-Boot should support any OS or standalone application
2630 easily, the main focus has always been on Linux during the design of
2633 U-Boot includes many features that so far have been part of some
2634 special "boot loader" code within the Linux kernel. Also, any
2635 "initrd" images to be used are no longer part of one big Linux image;
2636 instead, kernel and "initrd" are separate images. This implementation
2637 serves several purposes:
2639 - the same features can be used for other OS or standalone
2640 applications (for instance: using compressed images to reduce the
2641 Flash memory footprint)
2643 - it becomes much easier to port new Linux kernel versions because
2644 lots of low-level, hardware dependent stuff are done by U-Boot
2646 - the same Linux kernel image can now be used with different "initrd"
2647 images; of course this also means that different kernel images can
2648 be run with the same "initrd". This makes testing easier (you don't
2649 have to build a new "zImage.initrd" Linux image when you just
2650 change a file in your "initrd"). Also, a field-upgrade of the
2651 software is easier now.
2657 Porting Linux to U-Boot based systems:
2658 ---------------------------------------
2660 U-Boot cannot save you from doing all the necessary modifications to
2661 configure the Linux device drivers for use with your target hardware
2662 (no, we don't intend to provide a full virtual machine interface to
2665 But now you can ignore ALL boot loader code (in arch/ppc/mbxboot).
2667 Just make sure your machine specific header file (for instance
2668 include/asm-ppc/tqm8xx.h) includes the same definition of the Board
2669 Information structure as we define in include/u-boot.h, and make
2670 sure that your definition of IMAP_ADDR uses the same value as your
2671 U-Boot configuration in CFG_IMMR.
2674 Configuring the Linux kernel:
2675 -----------------------------
2677 No specific requirements for U-Boot. Make sure you have some root
2678 device (initial ramdisk, NFS) for your target system.
2681 Building a Linux Image:
2682 -----------------------
2684 With U-Boot, "normal" build targets like "zImage" or "bzImage" are
2685 not used. If you use recent kernel source, a new build target
2686 "uImage" will exist which automatically builds an image usable by
2687 U-Boot. Most older kernels also have support for a "pImage" target,
2688 which was introduced for our predecessor project PPCBoot and uses a
2689 100% compatible format.
2698 The "uImage" build target uses a special tool (in 'tools/mkimage') to
2699 encapsulate a compressed Linux kernel image with header information,
2700 CRC32 checksum etc. for use with U-Boot. This is what we are doing:
2702 * build a standard "vmlinux" kernel image (in ELF binary format):
2704 * convert the kernel into a raw binary image:
2706 ${CROSS_COMPILE}-objcopy -O binary \
2707 -R .note -R .comment \
2708 -S vmlinux linux.bin
2710 * compress the binary image:
2714 * package compressed binary image for U-Boot:
2716 mkimage -A ppc -O linux -T kernel -C gzip \
2717 -a 0 -e 0 -n "Linux Kernel Image" \
2718 -d linux.bin.gz uImage
2721 The "mkimage" tool can also be used to create ramdisk images for use
2722 with U-Boot, either separated from the Linux kernel image, or
2723 combined into one file. "mkimage" encapsulates the images with a 64
2724 byte header containing information about target architecture,
2725 operating system, image type, compression method, entry points, time
2726 stamp, CRC32 checksums, etc.
2728 "mkimage" can be called in two ways: to verify existing images and
2729 print the header information, or to build new images.
2731 In the first form (with "-l" option) mkimage lists the information
2732 contained in the header of an existing U-Boot image; this includes
2733 checksum verification:
2735 tools/mkimage -l image
2736 -l ==> list image header information
2738 The second form (with "-d" option) is used to build a U-Boot image
2739 from a "data file" which is used as image payload:
2741 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
2742 -n name -d data_file image
2743 -A ==> set architecture to 'arch'
2744 -O ==> set operating system to 'os'
2745 -T ==> set image type to 'type'
2746 -C ==> set compression type 'comp'
2747 -a ==> set load address to 'addr' (hex)
2748 -e ==> set entry point to 'ep' (hex)
2749 -n ==> set image name to 'name'
2750 -d ==> use image data from 'datafile'
2752 Right now, all Linux kernels for PowerPC systems use the same load
2753 address (0x00000000), but the entry point address depends on the
2756 - 2.2.x kernels have the entry point at 0x0000000C,
2757 - 2.3.x and later kernels have the entry point at 0x00000000.
2759 So a typical call to build a U-Boot image would read:
2761 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
2762 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
2763 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz \
2764 > examples/uImage.TQM850L
2765 Image Name: 2.4.4 kernel for TQM850L
2766 Created: Wed Jul 19 02:34:59 2000
2767 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2768 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
2769 Load Address: 0x00000000
2770 Entry Point: 0x00000000
2772 To verify the contents of the image (or check for corruption):
2774 -> tools/mkimage -l examples/uImage.TQM850L
2775 Image Name: 2.4.4 kernel for TQM850L
2776 Created: Wed Jul 19 02:34:59 2000
2777 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2778 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
2779 Load Address: 0x00000000
2780 Entry Point: 0x00000000
2782 NOTE: for embedded systems where boot time is critical you can trade
2783 speed for memory and install an UNCOMPRESSED image instead: this
2784 needs more space in Flash, but boots much faster since it does not
2785 need to be uncompressed:
2787 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz
2788 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
2789 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
2790 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux \
2791 > examples/uImage.TQM850L-uncompressed
2792 Image Name: 2.4.4 kernel for TQM850L
2793 Created: Wed Jul 19 02:34:59 2000
2794 Image Type: PowerPC Linux Kernel Image (uncompressed)
2795 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
2796 Load Address: 0x00000000
2797 Entry Point: 0x00000000
2800 Similar you can build U-Boot images from a 'ramdisk.image.gz' file
2801 when your kernel is intended to use an initial ramdisk:
2803 -> tools/mkimage -n 'Simple Ramdisk Image' \
2804 > -A ppc -O linux -T ramdisk -C gzip \
2805 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
2806 Image Name: Simple Ramdisk Image
2807 Created: Wed Jan 12 14:01:50 2000
2808 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2809 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
2810 Load Address: 0x00000000
2811 Entry Point: 0x00000000
2814 Installing a Linux Image:
2815 -------------------------
2817 To downloading a U-Boot image over the serial (console) interface,
2818 you must convert the image to S-Record format:
2820 objcopy -I binary -O srec examples/image examples/image.srec
2822 The 'objcopy' does not understand the information in the U-Boot
2823 image header, so the resulting S-Record file will be relative to
2824 address 0x00000000. To load it to a given address, you need to
2825 specify the target address as 'offset' parameter with the 'loads'
2828 Example: install the image to address 0x40100000 (which on the
2829 TQM8xxL is in the first Flash bank):
2831 => erase 40100000 401FFFFF
2837 ## Ready for S-Record download ...
2838 ~>examples/image.srec
2839 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
2841 15989 15990 15991 15992
2842 [file transfer complete]
2844 ## Start Addr = 0x00000000
2847 You can check the success of the download using the 'iminfo' command;
2848 this includes a checksum verification so you can be sure no data
2849 corruption happened:
2853 ## Checking Image at 40100000 ...
2854 Image Name: 2.2.13 for initrd on TQM850L
2855 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2856 Data Size: 335725 Bytes = 327 kB = 0 MB
2857 Load Address: 00000000
2858 Entry Point: 0000000c
2859 Verifying Checksum ... OK
2865 The "bootm" command is used to boot an application that is stored in
2866 memory (RAM or Flash). In case of a Linux kernel image, the contents
2867 of the "bootargs" environment variable is passed to the kernel as
2868 parameters. You can check and modify this variable using the
2869 "printenv" and "setenv" commands:
2872 => printenv bootargs
2873 bootargs=root=/dev/ram
2875 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2877 => printenv bootargs
2878 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2881 ## Booting Linux kernel at 40020000 ...
2882 Image Name: 2.2.13 for NFS on TQM850L
2883 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2884 Data Size: 381681 Bytes = 372 kB = 0 MB
2885 Load Address: 00000000
2886 Entry Point: 0000000c
2887 Verifying Checksum ... OK
2888 Uncompressing Kernel Image ... OK
2889 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
2890 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2891 time_init: decrementer frequency = 187500000/60
2892 Calibrating delay loop... 49.77 BogoMIPS
2893 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
2896 If you want to boot a Linux kernel with initial ram disk, you pass
2897 the memory addresses of both the kernel and the initrd image (PPBCOOT
2898 format!) to the "bootm" command:
2900 => imi 40100000 40200000
2902 ## Checking Image at 40100000 ...
2903 Image Name: 2.2.13 for initrd on TQM850L
2904 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2905 Data Size: 335725 Bytes = 327 kB = 0 MB
2906 Load Address: 00000000
2907 Entry Point: 0000000c
2908 Verifying Checksum ... OK
2910 ## Checking Image at 40200000 ...
2911 Image Name: Simple Ramdisk Image
2912 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2913 Data Size: 566530 Bytes = 553 kB = 0 MB
2914 Load Address: 00000000
2915 Entry Point: 00000000
2916 Verifying Checksum ... OK
2918 => bootm 40100000 40200000
2919 ## Booting Linux kernel at 40100000 ...
2920 Image Name: 2.2.13 for initrd on TQM850L
2921 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2922 Data Size: 335725 Bytes = 327 kB = 0 MB
2923 Load Address: 00000000
2924 Entry Point: 0000000c
2925 Verifying Checksum ... OK
2926 Uncompressing Kernel Image ... OK
2927 ## Loading RAMDisk Image at 40200000 ...
2928 Image Name: Simple Ramdisk Image
2929 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2930 Data Size: 566530 Bytes = 553 kB = 0 MB
2931 Load Address: 00000000
2932 Entry Point: 00000000
2933 Verifying Checksum ... OK
2934 Loading Ramdisk ... OK
2935 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
2936 Boot arguments: root=/dev/ram
2937 time_init: decrementer frequency = 187500000/60
2938 Calibrating delay loop... 49.77 BogoMIPS
2940 RAMDISK: Compressed image found at block 0
2941 VFS: Mounted root (ext2 filesystem).
2945 More About U-Boot Image Types:
2946 ------------------------------
2948 U-Boot supports the following image types:
2950 "Standalone Programs" are directly runnable in the environment
2951 provided by U-Boot; it is expected that (if they behave
2952 well) you can continue to work in U-Boot after return from
2953 the Standalone Program.
2954 "OS Kernel Images" are usually images of some Embedded OS which
2955 will take over control completely. Usually these programs
2956 will install their own set of exception handlers, device
2957 drivers, set up the MMU, etc. - this means, that you cannot
2958 expect to re-enter U-Boot except by resetting the CPU.
2959 "RAMDisk Images" are more or less just data blocks, and their
2960 parameters (address, size) are passed to an OS kernel that is
2962 "Multi-File Images" contain several images, typically an OS
2963 (Linux) kernel image and one or more data images like
2964 RAMDisks. This construct is useful for instance when you want
2965 to boot over the network using BOOTP etc., where the boot
2966 server provides just a single image file, but you want to get
2967 for instance an OS kernel and a RAMDisk image.
2969 "Multi-File Images" start with a list of image sizes, each
2970 image size (in bytes) specified by an "uint32_t" in network
2971 byte order. This list is terminated by an "(uint32_t)0".
2972 Immediately after the terminating 0 follow the images, one by
2973 one, all aligned on "uint32_t" boundaries (size rounded up to
2974 a multiple of 4 bytes).
2976 "Firmware Images" are binary images containing firmware (like
2977 U-Boot or FPGA images) which usually will be programmed to
2980 "Script files" are command sequences that will be executed by
2981 U-Boot's command interpreter; this feature is especially
2982 useful when you configure U-Boot to use a real shell (hush)
2983 as command interpreter.
2989 One of the features of U-Boot is that you can dynamically load and
2990 run "standalone" applications, which can use some resources of
2991 U-Boot like console I/O functions or interrupt services.
2993 Two simple examples are included with the sources:
2998 'examples/hello_world.c' contains a small "Hello World" Demo
2999 application; it is automatically compiled when you build U-Boot.
3000 It's configured to run at address 0x00040004, so you can play with it
3004 ## Ready for S-Record download ...
3005 ~>examples/hello_world.srec
3006 1 2 3 4 5 6 7 8 9 10 11 ...
3007 [file transfer complete]
3009 ## Start Addr = 0x00040004
3011 => go 40004 Hello World! This is a test.
3012 ## Starting application at 0x00040004 ...
3023 Hit any key to exit ...
3025 ## Application terminated, rc = 0x0
3027 Another example, which demonstrates how to register a CPM interrupt
3028 handler with the U-Boot code, can be found in 'examples/timer.c'.
3029 Here, a CPM timer is set up to generate an interrupt every second.
3030 The interrupt service routine is trivial, just printing a '.'
3031 character, but this is just a demo program. The application can be
3032 controlled by the following keys:
3034 ? - print current values og the CPM Timer registers
3035 b - enable interrupts and start timer
3036 e - stop timer and disable interrupts
3037 q - quit application
3040 ## Ready for S-Record download ...
3041 ~>examples/timer.srec
3042 1 2 3 4 5 6 7 8 9 10 11 ...
3043 [file transfer complete]
3045 ## Start Addr = 0x00040004
3048 ## Starting application at 0x00040004 ...
3051 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
3054 [q, b, e, ?] Set interval 1000000 us
3057 [q, b, e, ?] ........
3058 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
3061 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
3064 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
3067 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
3069 [q, b, e, ?] ...Stopping timer
3071 [q, b, e, ?] ## Application terminated, rc = 0x0
3077 Over time, many people have reported problems when trying to use the
3078 "minicom" terminal emulation program for serial download. I (wd)
3079 consider minicom to be broken, and recommend not to use it. Under
3080 Unix, I recommend to use C-Kermit for general purpose use (and
3081 especially for kermit binary protocol download ("loadb" command), and
3082 use "cu" for S-Record download ("loads" command).
3084 Nevertheless, if you absolutely want to use it try adding this
3085 configuration to your "File transfer protocols" section:
3087 Name Program Name U/D FullScr IO-Red. Multi
3088 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
3089 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
3095 Starting at version 0.9.2, U-Boot supports NetBSD both as host
3096 (build U-Boot) and target system (boots NetBSD/mpc8xx).
3098 Building requires a cross environment; it is known to work on
3099 NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
3100 need gmake since the Makefiles are not compatible with BSD make).
3101 Note that the cross-powerpc package does not install include files;
3102 attempting to build U-Boot will fail because <machine/ansi.h> is
3103 missing. This file has to be installed and patched manually:
3105 # cd /usr/pkg/cross/powerpc-netbsd/include
3107 # ln -s powerpc machine
3108 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
3109 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
3111 Native builds *don't* work due to incompatibilities between native
3112 and U-Boot include files.
3114 Booting assumes that (the first part of) the image booted is a
3115 stage-2 loader which in turn loads and then invokes the kernel
3116 proper. Loader sources will eventually appear in the NetBSD source
3117 tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
3118 meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
3121 Implementation Internals:
3122 =========================
3124 The following is not intended to be a complete description of every
3125 implementation detail. However, it should help to understand the
3126 inner workings of U-Boot and make it easier to port it to custom
3130 Initial Stack, Global Data:
3131 ---------------------------
3133 The implementation of U-Boot is complicated by the fact that U-Boot
3134 starts running out of ROM (flash memory), usually without access to
3135 system RAM (because the memory controller is not initialized yet).
3136 This means that we don't have writable Data or BSS segments, and BSS
3137 is not initialized as zero. To be able to get a C environment working
3138 at all, we have to allocate at least a minimal stack. Implementation
3139 options for this are defined and restricted by the CPU used: Some CPU
3140 models provide on-chip memory (like the IMMR area on MPC8xx and
3141 MPC826x processors), on others (parts of) the data cache can be
3142 locked as (mis-) used as memory, etc.
3144 Chris Hallinan posted a good summary of these issues to the
3145 u-boot-users mailing list:
3147 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
3148 From: "Chris Hallinan" <clh@net1plus.com>
3149 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
3152 Correct me if I'm wrong, folks, but the way I understand it
3153 is this: Using DCACHE as initial RAM for Stack, etc, does not
3154 require any physical RAM backing up the cache. The cleverness
3155 is that the cache is being used as a temporary supply of
3156 necessary storage before the SDRAM controller is setup. It's
3157 beyond the scope of this list to expain the details, but you
3158 can see how this works by studying the cache architecture and
3159 operation in the architecture and processor-specific manuals.
3161 OCM is On Chip Memory, which I believe the 405GP has 4K. It
3162 is another option for the system designer to use as an
3163 initial stack/ram area prior to SDRAM being available. Either
3164 option should work for you. Using CS 4 should be fine if your
3165 board designers haven't used it for something that would
3166 cause you grief during the initial boot! It is frequently not
3169 CFG_INIT_RAM_ADDR should be somewhere that won't interfere
3170 with your processor/board/system design. The default value
3171 you will find in any recent u-boot distribution in
3172 walnut.h should work for you. I'd set it to a value larger
3173 than your SDRAM module. If you have a 64MB SDRAM module, set
3174 it above 400_0000. Just make sure your board has no resources
3175 that are supposed to respond to that address! That code in
3176 start.S has been around a while and should work as is when
3177 you get the config right.
3182 It is essential to remember this, since it has some impact on the C
3183 code for the initialization procedures:
3185 * Initialized global data (data segment) is read-only. Do not attempt
3188 * Do not use any unitialized global data (or implicitely initialized
3189 as zero data - BSS segment) at all - this is undefined, initiali-
3190 zation is performed later (when relocating to RAM).
3192 * Stack space is very limited. Avoid big data buffers or things like
3195 Having only the stack as writable memory limits means we cannot use
3196 normal global data to share information beween the code. But it
3197 turned out that the implementation of U-Boot can be greatly
3198 simplified by making a global data structure (gd_t) available to all
3199 functions. We could pass a pointer to this data as argument to _all_
3200 functions, but this would bloat the code. Instead we use a feature of
3201 the GCC compiler (Global Register Variables) to share the data: we
3202 place a pointer (gd) to the global data into a register which we
3203 reserve for this purpose.
3205 When choosing a register for such a purpose we are restricted by the
3206 relevant (E)ABI specifications for the current architecture, and by
3207 GCC's implementation.
3209 For PowerPC, the following registers have specific use:
3212 R3-R4: parameter passing and return values
3213 R5-R10: parameter passing
3214 R13: small data area pointer
3218 (U-Boot also uses R14 as internal GOT pointer.)
3220 ==> U-Boot will use R29 to hold a pointer to the global data
3222 Note: on PPC, we could use a static initializer (since the
3223 address of the global data structure is known at compile time),
3224 but it turned out that reserving a register results in somewhat
3225 smaller code - although the code savings are not that big (on
3226 average for all boards 752 bytes for the whole U-Boot image,
3227 624 text + 127 data).
3229 On ARM, the following registers are used:
3231 R0: function argument word/integer result
3232 R1-R3: function argument word
3234 R10: stack limit (used only if stack checking if enabled)
3235 R11: argument (frame) pointer
3236 R12: temporary workspace
3239 R15: program counter
3241 ==> U-Boot will use R8 to hold a pointer to the global data
3247 U-Boot runs in system state and uses physical addresses, i.e. the
3248 MMU is not used either for address mapping nor for memory protection.
3250 The available memory is mapped to fixed addresses using the memory
3251 controller. In this process, a contiguous block is formed for each
3252 memory type (Flash, SDRAM, SRAM), even when it consists of several
3253 physical memory banks.
3255 U-Boot is installed in the first 128 kB of the first Flash bank (on
3256 TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
3257 booting and sizing and initializing DRAM, the code relocates itself
3258 to the upper end of DRAM. Immediately below the U-Boot code some
3259 memory is reserved for use by malloc() [see CFG_MALLOC_LEN
3260 configuration setting]. Below that, a structure with global Board
3261 Info data is placed, followed by the stack (growing downward).
3263 Additionally, some exception handler code is copied to the low 8 kB
3264 of DRAM (0x00000000 ... 0x00001FFF).
3266 So a typical memory configuration with 16 MB of DRAM could look like
3269 0x0000 0000 Exception Vector code
3272 0x0000 2000 Free for Application Use
3278 0x00FB FF20 Monitor Stack (Growing downward)
3279 0x00FB FFAC Board Info Data and permanent copy of global data
3280 0x00FC 0000 Malloc Arena
3283 0x00FE 0000 RAM Copy of Monitor Code
3284 ... eventually: LCD or video framebuffer
3285 ... eventually: pRAM (Protected RAM - unchanged by reset)
3286 0x00FF FFFF [End of RAM]
3289 System Initialization:
3290 ----------------------
3292 In the reset configuration, U-Boot starts at the reset entry point
3293 (on most PowerPC systens at address 0x00000100). Because of the reset
3294 configuration for CS0# this is a mirror of the onboard Flash memory.
3295 To be able to re-map memory U-Boot then jumps to its link address.
3296 To be able to implement the initialization code in C, a (small!)
3297 initial stack is set up in the internal Dual Ported RAM (in case CPUs
3298 which provide such a feature like MPC8xx or MPC8260), or in a locked
3299 part of the data cache. After that, U-Boot initializes the CPU core,
3300 the caches and the SIU.
3302 Next, all (potentially) available memory banks are mapped using a
3303 preliminary mapping. For example, we put them on 512 MB boundaries
3304 (multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
3305 on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
3306 programmed for SDRAM access. Using the temporary configuration, a
3307 simple memory test is run that determines the size of the SDRAM
3310 When there is more than one SDRAM bank, and the banks are of
3311 different size, the largest is mapped first. For equal size, the first
3312 bank (CS2#) is mapped first. The first mapping is always for address
3313 0x00000000, with any additional banks following immediately to create
3314 contiguous memory starting from 0.
3316 Then, the monitor installs itself at the upper end of the SDRAM area
3317 and allocates memory for use by malloc() and for the global Board
3318 Info data; also, the exception vector code is copied to the low RAM
3319 pages, and the final stack is set up.
3321 Only after this relocation will you have a "normal" C environment;
3322 until that you are restricted in several ways, mostly because you are
3323 running from ROM, and because the code will have to be relocated to a
3327 U-Boot Porting Guide:
3328 ----------------------
3330 [Based on messages by Jerry Van Baren in the U-Boot-Users mailing
3334 int main (int argc, char *argv[])
3336 sighandler_t no_more_time;
3338 signal (SIGALRM, no_more_time);
3339 alarm (PROJECT_DEADLINE - toSec (3 * WEEK));
3341 if (available_money > available_manpower) {
3342 pay consultant to port U-Boot;
3346 Download latest U-Boot source;
3348 Subscribe to u-boot-users mailing list;
3351 email ("Hi, I am new to U-Boot, how do I get started?");
3355 Read the README file in the top level directory;
3356 Read http://www.denx.de/twiki/bin/view/DULG/Manual ;
3357 Read the source, Luke;
3360 if (available_money > toLocalCurrency ($2500)) {
3363 Add a lot of aggravation and time;
3366 Create your own board support subdirectory;
3368 Create your own board config file;
3372 Add / modify source code;
3376 email ("Hi, I am having problems...");
3378 Send patch file to Wolfgang;
3383 void no_more_time (int sig)
3392 All contributions to U-Boot should conform to the Linux kernel
3393 coding style; see the file "Documentation/CodingStyle" in your Linux
3394 kernel source directory.
3396 Please note that U-Boot is implemented in C (and to some small parts
3397 in Assembler); no C++ is used, so please do not use C++ style
3398 comments (//) in your code.
3400 Please also stick to the following formatting rules:
3401 - remove any trailing white space
3402 - use TAB characters for indentation, not spaces
3403 - make sure NOT to use DOS '\r\n' line feeds
3404 - do not add more than 2 empty lines to source files
3405 - do not add trailing empty lines to source files
3407 Submissions which do not conform to the standards may be returned
3408 with a request to reformat the changes.
3414 Since the number of patches for U-Boot is growing, we need to
3415 establish some rules. Submissions which do not conform to these rules
3416 may be rejected, even when they contain important and valuable stuff.
3418 Patches shall be sent to the u-boot-users mailing list.
3420 When you send a patch, please include the following information with
3423 * For bug fixes: a description of the bug and how your patch fixes
3424 this bug. Please try to include a way of demonstrating that the
3425 patch actually fixes something.
3427 * For new features: a description of the feature and your
3430 * A CHANGELOG entry as plaintext (separate from the patch)
3432 * For major contributions, your entry to the CREDITS file
3434 * When you add support for a new board, don't forget to add this
3435 board to the MAKEALL script, too.
3437 * If your patch adds new configuration options, don't forget to
3438 document these in the README file.
3440 * The patch itself. If you are accessing the CVS repository use "cvs
3441 update; cvs diff -puRN"; else, use "diff -purN OLD NEW". If your
3442 version of diff does not support these options, then get the latest
3443 version of GNU diff.
3445 The current directory when running this command shall be the top
3446 level directory of the U-Boot source tree, or it's parent directory
3447 (i. e. please make sure that your patch includes sufficient
3448 directory information for the affected files).
3450 We accept patches as plain text, MIME attachments or as uuencoded
3453 * If one logical set of modifications affects or creates several
3454 files, all these changes shall be submitted in a SINGLE patch file.
3456 * Changesets that contain different, unrelated modifications shall be
3457 submitted as SEPARATE patches, one patch per changeset.
3462 * Before sending the patch, run the MAKEALL script on your patched
3463 source tree and make sure that no errors or warnings are reported
3464 for any of the boards.
3466 * Keep your modifications to the necessary minimum: A patch
3467 containing several unrelated changes or arbitrary reformats will be
3468 returned with a request to re-formatting / split it.
3470 * If you modify existing code, make sure that your new code does not
3471 add to the memory footprint of the code ;-) Small is beautiful!
3472 When adding new features, these should compile conditionally only
3473 (using #ifdef), and the resulting code with the new feature
3474 disabled must not need more memory than the old code without your
3477 * Remember that there is a size limit of 40 kB per message on the
3478 u-boot-users mailing list. Compression may help.
projects / kernel / u-boot.git / blob