2 # (C) Copyright 2000 - 2004
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 and ARM processors, which can be
29 installed in a boot ROM and used to initialize and test the hardware
30 or to download and run application code.
32 The development of U-Boot is closely related to Linux: some parts of
33 the source code originate in the Linux source tree, we have some
34 header files in common, and special provision has been made to
35 support booting of Linux images.
37 Some attention has been paid to make this software easily
38 configurable and extendable. For instance, all monitor commands are
39 implemented with the same call interface, so that it's very easy to
40 add new commands. Also, instead of permanently adding rarely used
41 code (for instance hardware test utilities) to the monitor, you can
42 load and run it dynamically.
48 In general, all boards for which a configuration option exists in the
49 Makefile have been tested to some extent and can be considered
50 "working". In fact, many of them are used in production systems.
52 In case of problems see the CHANGELOG and CREDITS files to find out
53 who contributed the specific port.
59 In case you have questions about, problems with or contributions for
60 U-Boot you should send a message to the U-Boot mailing list at
61 <u-boot-users@lists.sourceforge.net>. There is also an archive of
62 previous traffic on the mailing list - please search the archive
63 before asking FAQ's. Please see
64 http://lists.sourceforge.net/lists/listinfo/u-boot-users/
70 - start from 8xxrom sources
71 - create PPCBoot project (http://sourceforge.net/projects/ppcboot)
73 - make it easier to add custom boards
74 - make it possible to add other [PowerPC] CPUs
75 - extend functions, especially:
76 * Provide extended interface to Linux boot loader
79 * PCMCIA / CompactFLash / ATA disk / SCSI ... boot
80 - create ARMBoot project (http://sourceforge.net/projects/armboot)
81 - add other CPU families (starting with ARM)
82 - create U-Boot project (http://sourceforge.net/projects/u-boot)
88 The "official" name of this project is "Das U-Boot". The spelling
89 "U-Boot" shall be used in all written text (documentation, comments
90 in source files etc.). Example:
92 This is the README file for the U-Boot project.
94 File names etc. shall be based on the string "u-boot". Examples:
96 include/asm-ppc/u-boot.h
98 #include <asm/u-boot.h>
100 Variable names, preprocessor constants etc. shall be either based on
101 the string "u_boot" or on "U_BOOT". Example:
103 U_BOOT_VERSION u_boot_logo
104 IH_OS_U_BOOT u_boot_hush_start
110 U-Boot uses a 3 level version number containing a version, a
111 sub-version, and a patchlevel: "U-Boot-2.34.5" means version "2",
112 sub-version "34", and patchlevel "4".
114 The patchlevel is used to indicate certain stages of development
115 between released versions, i. e. officially released versions of
116 U-Boot will always have a patchlevel of "0".
122 - board Board dependent files
123 - common Misc architecture independent functions
124 - cpu CPU specific files
125 - 74xx_7xx Files specific to Motorola MPC74xx and 7xx CPUs
126 - arm720t Files specific to ARM 720 CPUs
127 - arm920t Files specific to ARM 920 CPUs
128 - arm925t Files specific to ARM 925 CPUs
129 - arm926ejs Files specific to ARM 926 CPUs
130 - at91rm9200 Files specific to Atmel AT91RM9200 CPUs
131 - i386 Files specific to i386 CPUs
132 - ixp Files specific to Intel XScale IXP CPUs
133 - mcf52x2 Files specific to Motorola ColdFire MCF52x2 CPUs
134 - mips Files specific to MIPS CPUs
135 - mpc5xx Files specific to Motorola MPC5xx CPUs
136 - mpc5xxx Files specific to Motorola MPC5xxx CPUs
137 - mpc8xx Files specific to Motorola MPC8xx CPUs
138 - mpc824x Files specific to Motorola MPC824x CPUs
139 - mpc8260 Files specific to Motorola MPC8260 CPUs
140 - mpc85xx Files specific to Motorola MPC85xx CPUs
141 - nios Files specific to Altera NIOS CPUs
142 - ppc4xx Files specific to IBM PowerPC 4xx CPUs
143 - pxa Files specific to Intel XScale PXA CPUs
144 - s3c44b0 Files specific to Samsung S3C44B0 CPUs
145 - sa1100 Files specific to Intel StrongARM SA1100 CPUs
146 - disk Code for disk drive partition handling
147 - doc Documentation (don't expect too much)
148 - drivers Commonly used device drivers
149 - dtt Digital Thermometer and Thermostat drivers
150 - examples Example code for standalone applications, etc.
151 - include Header Files
152 - lib_arm Files generic to ARM architecture
153 - lib_generic Files generic to all architectures
154 - lib_i386 Files generic to i386 architecture
155 - lib_m68k Files generic to m68k architecture
156 - lib_mips Files generic to MIPS architecture
157 - lib_nios Files generic to NIOS architecture
158 - lib_ppc Files generic to PowerPC architecture
159 - net Networking code
160 - post Power On Self Test
161 - rtc Real Time Clock drivers
162 - tools Tools to build S-Record or U-Boot images, etc.
164 Software Configuration:
165 =======================
167 Configuration is usually done using C preprocessor defines; the
168 rationale behind that is to avoid dead code whenever possible.
170 There are two classes of configuration variables:
172 * Configuration _OPTIONS_:
173 These are selectable by the user and have names beginning with
176 * Configuration _SETTINGS_:
177 These depend on the hardware etc. and should not be meddled with if
178 you don't know what you're doing; they have names beginning with
181 Later we will add a configuration tool - probably similar to or even
182 identical to what's used for the Linux kernel. Right now, we have to
183 do the configuration by hand, which means creating some symbolic
184 links and editing some configuration files. We use the TQM8xxL boards
188 Selection of Processor Architecture and Board Type:
189 ---------------------------------------------------
191 For all supported boards there are ready-to-use default
192 configurations available; just type "make <board_name>_config".
194 Example: For a TQM823L module type:
199 For the Cogent platform, you need to specify the cpu type as well;
200 e.g. "make cogent_mpc8xx_config". And also configure the cogent
201 directory according to the instructions in cogent/README.
204 Configuration Options:
205 ----------------------
207 Configuration depends on the combination of board and CPU type; all
208 such information is kept in a configuration file
209 "include/configs/<board_name>.h".
211 Example: For a TQM823L module, all configuration settings are in
212 "include/configs/TQM823L.h".
215 Many of the options are named exactly as the corresponding Linux
216 kernel configuration options. The intention is to make it easier to
217 build a config tool - later.
220 The following options need to be configured:
222 - CPU Type: Define exactly one of
226 CONFIG_MPC823, CONFIG_MPC850, CONFIG_MPC855, CONFIG_MPC860
228 or CONFIG_MPC824X, CONFIG_MPC8260
243 MicroBlaze based CPUs:
244 ----------------------
248 - Board Type: Define exactly one of
250 PowerPC based boards:
251 ---------------------
253 CONFIG_ADCIOP, CONFIG_ADS860, CONFIG_AMX860,
254 CONFIG_AR405, CONFIG_BAB7xx, CONFIG_c2mon,
255 CONFIG_CANBT, CONFIG_CCM, CONFIG_CMI,
256 CONFIG_cogent_mpc8260, CONFIG_cogent_mpc8xx, CONFIG_CPCI405,
257 CONFIG_CPCI4052, CONFIG_CPCIISER4, CONFIG_CPU86,
258 CONFIG_CRAYL1, CONFIG_CU824, CONFIG_DASA_SIM,
259 CONFIG_DB64360, CONFIG_DB64460, CONFIG_DU405,
260 CONFIG_DUET_ADS, CONFIG_EBONY, CONFIG_ELPPC,
261 CONFIG_ELPT860, CONFIG_ep8260, CONFIG_ERIC,
262 CONFIG_ESTEEM192E, CONFIG_ETX094, CONFIG_EVB64260,
263 CONFIG_FADS823, CONFIG_FADS850SAR, CONFIG_FADS860T,
264 CONFIG_FLAGADM, CONFIG_FPS850L, CONFIG_FPS860L,
265 CONFIG_GEN860T, CONFIG_GENIETV, CONFIG_GTH,
266 CONFIG_gw8260, CONFIG_hermes, CONFIG_hymod,
267 CONFIG_IAD210, CONFIG_ICU862, CONFIG_IP860,
268 CONFIG_IPHASE4539, CONFIG_IVML24, CONFIG_IVML24_128,
269 CONFIG_IVML24_256, CONFIG_IVMS8, CONFIG_IVMS8_128,
270 CONFIG_IVMS8_256, CONFIG_JSE, CONFIG_LANTEC,
271 CONFIG_lwmon, CONFIG_MBX, CONFIG_MBX860T,
272 CONFIG_MHPC, CONFIG_MIP405, CONFIG_MOUSSE,
273 CONFIG_MPC8260ADS, CONFIG_MPC8540ADS, CONFIG_MPC8560ADS,
274 CONFIG_MUSENKI, CONFIG_MVS1, CONFIG_NETPHONE,
275 CONFIG_NETTA, CONFIG_NETVIA, CONFIG_NX823,
276 CONFIG_OCRTC, CONFIG_ORSG, CONFIG_OXC,
277 CONFIG_PCI405, CONFIG_PCIPPC2, CONFIG_PCIPPC6,
278 CONFIG_pcu_e, CONFIG_PIP405, CONFIG_PM826,
279 CONFIG_ppmc8260, CONFIG_QS823, CONFIG_QS850,
280 CONFIG_QS860T, CONFIG_RBC823, CONFIG_RPXClassic,
281 CONFIG_RPXlite, CONFIG_RPXsuper, CONFIG_rsdproto,
282 CONFIG_sacsng, CONFIG_Sandpoint8240, CONFIG_Sandpoint8245,
283 CONFIG_sbc8260, CONFIG_SM850, CONFIG_SPD823TS,
284 CONFIG_STXGP3, CONFIG_SXNI855T, CONFIG_TQM823L,
285 CONFIG_TQM8260, CONFIG_TQM850L, CONFIG_TQM855L,
286 CONFIG_TQM860L, CONFIG_TTTech, CONFIG_UTX8245,
287 CONFIG_V37, CONFIG_W7OLMC, CONFIG_W7OLMG,
288 CONFIG_WALNUT405, CONFIG_ZPC1900, CONFIG_ZUMA,
293 CONFIG_AT91RM9200DK, CONFIG_DNP1110, CONFIG_EP7312,
294 CONFIG_H2_OMAP1610, CONFIG_HHP_CRADLE, CONFIG_IMPA7,
295 CONFIG_INNOVATOROMAP1510, CONFIG_INNOVATOROMAP1610, CONFIG_LART,
296 CONFIG_LUBBOCK, CONFIG_SHANNON, CONFIG_SMDK2400,
297 CONFIG_SMDK2410, CONFIG_TRAB, CONFIG_VCMA9,
299 MicroBlaze based boards:
300 ------------------------
305 - CPU Module Type: (if CONFIG_COGENT is defined)
306 Define exactly one of
308 --- FIXME --- not tested yet:
309 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P,
310 CONFIG_CMA287_23, CONFIG_CMA287_50
312 - Motherboard Type: (if CONFIG_COGENT is defined)
313 Define exactly one of
314 CONFIG_CMA101, CONFIG_CMA102
316 - Motherboard I/O Modules: (if CONFIG_COGENT is defined)
317 Define one or more of
320 - Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined)
321 Define one or more of
322 CONFIG_LCD_HEARTBEAT - update a character position on
323 the lcd display every second with
326 - Board flavour: (if CONFIG_MPC8260ADS is defined)
329 CFG_8260ADS - original MPC8260ADS
330 CFG_8266ADS - MPC8266ADS
331 CFG_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR
332 CFG_8272ADS - MPC8272ADS
334 - MPC824X Family Member (if CONFIG_MPC824X is defined)
335 Define exactly one of
336 CONFIG_MPC8240, CONFIG_MPC8245
338 - 8xx CPU Options: (if using an MPC8xx cpu)
339 Define one or more of
340 CONFIG_8xx_GCLK_FREQ - if get_gclk_freq() cannot work
341 e.g. if there is no 32KHz
342 reference PIT/RTC clock
344 - 859/866 CPU options: (if using a MPC859 or MPC866 CPU):
348 CFG_866_CPUCLK_DEFAULT
349 See doc/README.MPC866
353 Define this to measure the actual CPU clock instead
354 of relying on the correctness of the configured
355 values. Mostly useful for board bringup to make sure
356 the PLL is locked at the intended frequency. Note
357 that this requires a (stable) reference clock (32 kHz
360 - Linux Kernel Interface:
363 U-Boot stores all clock information in Hz
364 internally. For binary compatibility with older Linux
365 kernels (which expect the clocks passed in the
366 bd_info data to be in MHz) the environment variable
367 "clocks_in_mhz" can be defined so that U-Boot
368 converts clock data to MHZ before passing it to the
370 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
371 "clocks_in_mhz=1" is automatically included in the
374 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
376 When transfering memsize parameter to linux, some versions
377 expect it to be in bytes, others in MB.
378 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
381 Depending on board, define exactly one serial port
382 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
383 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial
384 console by defining CONFIG_8xx_CONS_NONE
386 Note: if CONFIG_8xx_CONS_NONE is defined, the serial
387 port routines must be defined elsewhere
388 (i.e. serial_init(), serial_getc(), ...)
391 Enables console device for a color framebuffer. Needs following
392 defines (cf. smiLynxEM, i8042, board/eltec/bab7xx)
393 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation
395 VIDEO_HW_RECTFILL graphic chip supports
398 VIDEO_HW_BITBLT graphic chip supports
399 bit-blit (cf. smiLynxEM)
400 VIDEO_VISIBLE_COLS visible pixel columns
402 VIDEO_VISIBLE_ROWS visible pixel rows
403 VIDEO_PIXEL_SIZE bytes per pixel
404 VIDEO_DATA_FORMAT graphic data format
405 (0-5, cf. cfb_console.c)
406 VIDEO_FB_ADRS framebuffer address
407 VIDEO_KBD_INIT_FCT keyboard int fct
408 (i.e. i8042_kbd_init())
409 VIDEO_TSTC_FCT test char fct
411 VIDEO_GETC_FCT get char fct
413 CONFIG_CONSOLE_CURSOR cursor drawing on/off
414 (requires blink timer
416 CFG_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c)
417 CONFIG_CONSOLE_TIME display time/date info in
419 (requires CFG_CMD_DATE)
420 CONFIG_VIDEO_LOGO display Linux logo in
422 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of
423 linux_logo.h for logo.
424 Requires CONFIG_VIDEO_LOGO
425 CONFIG_CONSOLE_EXTRA_INFO
426 addional board info beside
429 When CONFIG_CFB_CONSOLE is defined, video console is
430 default i/o. Serial console can be forced with
431 environment 'console=serial'.
433 When CONFIG_SILENT_CONSOLE is defined, all console
434 messages (by U-Boot and Linux!) can be silenced with
435 the "silent" environment variable. See
436 doc/README.silent for more information.
439 CONFIG_BAUDRATE - in bps
440 Select one of the baudrates listed in
441 CFG_BAUDRATE_TABLE, see below.
442 CFG_BRGCLK_PRESCALE, baudrate prescale
444 - Interrupt driven serial port input:
445 CONFIG_SERIAL_SOFTWARE_FIFO
448 Use an interrupt handler for receiving data on the
449 serial port. It also enables using hardware handshake
450 (RTS/CTS) and UART's built-in FIFO. Set the number of
451 bytes the interrupt driven input buffer should have.
453 Leave undefined to disable this feature, including
454 disable the buffer and hardware handshake.
456 - Console UART Number:
460 If defined internal UART1 (and not UART0) is used
461 as default U-Boot console.
463 - Boot Delay: CONFIG_BOOTDELAY - in seconds
464 Delay before automatically booting the default image;
465 set to -1 to disable autoboot.
467 See doc/README.autoboot for these options that
468 work with CONFIG_BOOTDELAY. None are required.
469 CONFIG_BOOT_RETRY_TIME
470 CONFIG_BOOT_RETRY_MIN
471 CONFIG_AUTOBOOT_KEYED
472 CONFIG_AUTOBOOT_PROMPT
473 CONFIG_AUTOBOOT_DELAY_STR
474 CONFIG_AUTOBOOT_STOP_STR
475 CONFIG_AUTOBOOT_DELAY_STR2
476 CONFIG_AUTOBOOT_STOP_STR2
477 CONFIG_ZERO_BOOTDELAY_CHECK
478 CONFIG_RESET_TO_RETRY
482 Only needed when CONFIG_BOOTDELAY is enabled;
483 define a command string that is automatically executed
484 when no character is read on the console interface
485 within "Boot Delay" after reset.
488 This can be used to pass arguments to the bootm
489 command. The value of CONFIG_BOOTARGS goes into the
490 environment value "bootargs".
492 CONFIG_RAMBOOT and CONFIG_NFSBOOT
493 The value of these goes into the environment as
494 "ramboot" and "nfsboot" respectively, and can be used
495 as a convenience, when switching between booting from
501 When this option is #defined, the existence of the
502 environment variable "preboot" will be checked
503 immediately before starting the CONFIG_BOOTDELAY
504 countdown and/or running the auto-boot command resp.
505 entering interactive mode.
507 This feature is especially useful when "preboot" is
508 automatically generated or modified. For an example
509 see the LWMON board specific code: here "preboot" is
510 modified when the user holds down a certain
511 combination of keys on the (special) keyboard when
514 - Serial Download Echo Mode:
516 If defined to 1, all characters received during a
517 serial download (using the "loads" command) are
518 echoed back. This might be needed by some terminal
519 emulations (like "cu"), but may as well just take
520 time on others. This setting #define's the initial
521 value of the "loads_echo" environment variable.
523 - Kgdb Serial Baudrate: (if CFG_CMD_KGDB is defined)
525 Select one of the baudrates listed in
526 CFG_BAUDRATE_TABLE, see below.
530 Most monitor functions can be selected (or
531 de-selected) by adjusting the definition of
532 CONFIG_COMMANDS; to select individual functions,
533 #define CONFIG_COMMANDS by "OR"ing any of the
536 #define enables commands:
537 -------------------------
538 CFG_CMD_ASKENV * ask for env variable
539 CFG_CMD_AUTOSCRIPT Autoscript Support
541 CFG_CMD_BEDBUG Include BedBug Debugger
542 CFG_CMD_BMP * BMP support
544 CFG_CMD_CACHE icache, dcache
545 CFG_CMD_CONSOLE coninfo
546 CFG_CMD_DATE * support for RTC, date/time...
547 CFG_CMD_DHCP DHCP support
548 CFG_CMD_DIAG * Diagnostics
549 CFG_CMD_DOC * Disk-On-Chip Support
550 CFG_CMD_DTT Digital Therm and Thermostat
551 CFG_CMD_ECHO * echo arguments
552 CFG_CMD_EEPROM * EEPROM read/write support
553 CFG_CMD_ELF bootelf, bootvx
555 CFG_CMD_FDC * Floppy Disk Support
556 CFG_CMD_FAT FAT partition support
557 CFG_CMD_FDOS * Dos diskette Support
558 CFG_CMD_FLASH flinfo, erase, protect
559 CFG_CMD_FPGA FPGA device initialization support
560 CFG_CMD_HWFLOW * RTS/CTS hw flow control
561 CFG_CMD_I2C * I2C serial bus support
562 CFG_CMD_IDE * IDE harddisk support
564 CFG_CMD_IMLS List all found images
565 CFG_CMD_IMMAP * IMMR dump support
566 CFG_CMD_IRQ * irqinfo
567 CFG_CMD_ITEST * Integer/string test of 2 values
568 CFG_CMD_JFFS2 * JFFS2 Support
572 CFG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base,
574 CFG_CMD_MISC Misc functions like sleep etc
575 CFG_CMD_MMC MMC memory mapped support
576 CFG_CMD_MII MII utility commands
577 CFG_CMD_NAND * NAND support
578 CFG_CMD_NET bootp, tftpboot, rarpboot
579 CFG_CMD_PCI * pciinfo
580 CFG_CMD_PCMCIA * PCMCIA support
581 CFG_CMD_PING * send ICMP ECHO_REQUEST to network host
582 CFG_CMD_PORTIO * Port I/O
583 CFG_CMD_REGINFO * Register dump
584 CFG_CMD_RUN run command in env variable
585 CFG_CMD_SAVES save S record dump
586 CFG_CMD_SCSI * SCSI Support
587 CFG_CMD_SDRAM * print SDRAM configuration information
588 CFG_CMD_SETGETDCR Support for DCR Register access (4xx only)
589 CFG_CMD_SPI * SPI serial bus support
590 CFG_CMD_USB * USB support
591 CFG_CMD_VFD * VFD support (TRAB)
592 CFG_CMD_BSP * Board SPecific functions
593 CFG_CMD_CDP * Cisco Discover Protocol support
594 -----------------------------------------------
597 CFG_CMD_DFL Default configuration; at the moment
598 this is includes all commands, except
599 the ones marked with "*" in the list
602 If you don't define CONFIG_COMMANDS it defaults to
603 CFG_CMD_DFL in include/cmd_confdefs.h. A board can
604 override the default settings in the respective
607 EXAMPLE: If you want all functions except of network
608 support you can write:
610 #define CONFIG_COMMANDS (CFG_CMD_ALL & ~CFG_CMD_NET)
613 Note: Don't enable the "icache" and "dcache" commands
614 (configuration option CFG_CMD_CACHE) unless you know
615 what you (and your U-Boot users) are doing. Data
616 cache cannot be enabled on systems like the 8xx or
617 8260 (where accesses to the IMMR region must be
618 uncached), and it cannot be disabled on all other
619 systems where we (mis-) use the data cache to hold an
620 initial stack and some data.
623 XXX - this list needs to get updated!
627 If this variable is defined, it enables watchdog
628 support. There must be support in the platform specific
629 code for a watchdog. For the 8xx and 8260 CPUs, the
630 SIU Watchdog feature is enabled in the SYPCR
634 CONFIG_VERSION_VARIABLE
635 If this variable is defined, an environment variable
636 named "ver" is created by U-Boot showing the U-Boot
637 version as printed by the "version" command.
638 This variable is readonly.
642 When CFG_CMD_DATE is selected, the type of the RTC
643 has to be selected, too. Define exactly one of the
646 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx
647 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
648 CONFIG_RTC_MC146818 - use MC146818 RTC
649 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
650 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
651 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
652 CONFIG_RTC_DS164x - use Dallas DS164x RTC
654 Note that if the RTC uses I2C, then the I2C interface
655 must also be configured. See I2C Support, below.
659 When CONFIG_TIMESTAMP is selected, the timestamp
660 (date and time) of an image is printed by image
661 commands like bootm or iminfo. This option is
662 automatically enabled when you select CFG_CMD_DATE .
665 CONFIG_MAC_PARTITION and/or CONFIG_DOS_PARTITION
666 and/or CONFIG_ISO_PARTITION
668 If IDE or SCSI support is enabled (CFG_CMD_IDE or
669 CFG_CMD_SCSI) you must configure support for at least
670 one partition type as well.
673 CONFIG_IDE_RESET_ROUTINE - this is defined in several
674 board configurations files but used nowhere!
676 CONFIG_IDE_RESET - is this is defined, IDE Reset will
677 be performed by calling the function
678 ide_set_reset(int reset)
679 which has to be defined in a board specific file
684 Set this to enable ATAPI support.
689 Set this to enable support for disks larger than 137GB
690 Also look at CFG_64BIT_LBA ,CFG_64BIT_VSPRINTF and CFG_64BIT_STRTOUL
691 Whithout these , LBA48 support uses 32bit variables and will 'only'
692 support disks up to 2.1TB.
695 When enabled, makes the IDE subsystem use 64bit sector addresses.
699 At the moment only there is only support for the
700 SYM53C8XX SCSI controller; define
701 CONFIG_SCSI_SYM53C8XX to enable it.
703 CFG_SCSI_MAX_LUN [8], CFG_SCSI_MAX_SCSI_ID [7] and
704 CFG_SCSI_MAX_DEVICE [CFG_SCSI_MAX_SCSI_ID *
705 CFG_SCSI_MAX_LUN] can be adjusted to define the
706 maximum numbers of LUNs, SCSI ID's and target
708 CFG_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
710 - NETWORK Support (PCI):
712 Support for Intel 8254x gigabit chips.
715 Support for Intel 82557/82559/82559ER chips.
716 Optional CONFIG_EEPRO100_SROM_WRITE enables eeprom
717 write routine for first time initialisation.
720 Support for Digital 2114x chips.
721 Optional CONFIG_TULIP_SELECT_MEDIA for board specific
722 modem chip initialisation (KS8761/QS6611).
725 Support for National dp83815 chips.
728 Support for National dp8382[01] gigabit chips.
730 - NETWORK Support (other):
732 CONFIG_DRIVER_LAN91C96
733 Support for SMSC's LAN91C96 chips.
736 Define this to hold the physical address
737 of the LAN91C96's I/O space
739 CONFIG_LAN91C96_USE_32_BIT
740 Define this to enable 32 bit addressing
743 At the moment only the UHCI host controller is
744 supported (PIP405, MIP405, MPC5200); define
745 CONFIG_USB_UHCI to enable it.
746 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
747 end define CONFIG_USB_STORAGE to enable the USB
750 Supported are USB Keyboards and USB Floppy drives
752 MPC5200 USB requires additional defines:
754 for 528 MHz Clock: 0x0001bbbb
756 for differential drivers: 0x00001000
757 for single ended drivers: 0x00005000
761 The MMC controller on the Intel PXA is supported. To
762 enable this define CONFIG_MMC. The MMC can be
763 accessed from the boot prompt by mapping the device
764 to physical memory similar to flash. Command line is
765 enabled with CFG_CMD_MMC. The MMC driver also works with
766 the FAT fs. This is enabled with CFG_CMD_FAT.
771 Define this to enable standard (PC-Style) keyboard
775 Standard PC keyboard driver with US (is default) and
776 GERMAN key layout (switch via environment 'keymap=de') support.
777 Export function i8042_kbd_init, i8042_tstc and i8042_getc
778 for cfb_console. Supports cursor blinking.
783 Define this to enable video support (for output to
788 Enable Chips & Technologies 69000 Video chip
790 CONFIG_VIDEO_SMI_LYNXEM
791 Enable Silicon Motion SMI 712/710/810 Video chip. The
792 video output is selected via environment 'videoout'
793 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is
796 For the CT69000 and SMI_LYNXEM drivers, videomode is
797 selected via environment 'videomode'. Two diferent ways
799 - "videomode=num" 'num' is a standard LiLo mode numbers.
800 Following standard modes are supported (* is default):
802 Colors 640x480 800x600 1024x768 1152x864 1280x1024
803 -------------+---------------------------------------------
804 8 bits | 0x301* 0x303 0x305 0x161 0x307
805 15 bits | 0x310 0x313 0x316 0x162 0x319
806 16 bits | 0x311 0x314 0x317 0x163 0x31A
807 24 bits | 0x312 0x315 0x318 ? 0x31B
808 -------------+---------------------------------------------
809 (i.e. setenv videomode 317; saveenv; reset;)
811 - "videomode=bootargs" all the video parameters are parsed
812 from the bootargs. (See drivers/videomodes.c)
815 CONFIG_VIDEO_SED13806
816 Enable Epson SED13806 driver. This driver supports 8bpp
817 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
818 or CONFIG_VIDEO_SED13806_16BPP
823 Define this to enable a custom keyboard support.
824 This simply calls drv_keyboard_init() which must be
825 defined in your board-specific files.
826 The only board using this so far is RBC823.
828 - LCD Support: CONFIG_LCD
830 Define this to enable LCD support (for output to LCD
831 display); also select one of the supported displays
832 by defining one of these:
834 CONFIG_NEC_NL6448AC33:
836 NEC NL6448AC33-18. Active, color, single scan.
838 CONFIG_NEC_NL6448BC20
840 NEC NL6448BC20-08. 6.5", 640x480.
841 Active, color, single scan.
843 CONFIG_NEC_NL6448BC33_54
845 NEC NL6448BC33-54. 10.4", 640x480.
846 Active, color, single scan.
850 Sharp 320x240. Active, color, single scan.
851 It isn't 16x9, and I am not sure what it is.
853 CONFIG_SHARP_LQ64D341
855 Sharp LQ64D341 display, 640x480.
856 Active, color, single scan.
860 HLD1045 display, 640x480.
861 Active, color, single scan.
865 Optrex CBL50840-2 NF-FW 99 22 M5
867 Hitachi LMG6912RPFC-00T
871 320x240. Black & white.
873 Normally display is black on white background; define
874 CFG_WHITE_ON_BLACK to get it inverted.
876 - Splash Screen Support: CONFIG_SPLASH_SCREEN
878 If this option is set, the environment is checked for
879 a variable "splashimage". If found, the usual display
880 of logo, copyright and system information on the LCD
881 is supressed and the BMP image at the address
882 specified in "splashimage" is loaded instead. The
883 console is redirected to the "nulldev", too. This
884 allows for a "silent" boot where a splash screen is
885 loaded very quickly after power-on.
887 - Compression support:
890 If this option is set, support for bzip2 compressed
891 images is included. If not, only uncompressed and gzip
892 compressed images are supported.
894 NOTE: the bzip2 algorithm requires a lot of RAM, so
895 the malloc area (as defined by CFG_MALLOC_LEN) should
903 Define a default value for ethernet address to use
904 for the respective ethernet interface, in case this
905 is not determined automatically.
910 Define a default value for the IP address to use for
911 the default ethernet interface, in case this is not
912 determined through e.g. bootp.
917 Defines a default value for theIP address of a TFTP
918 server to contact when using the "tftboot" command.
920 - BOOTP Recovery Mode:
921 CONFIG_BOOTP_RANDOM_DELAY
923 If you have many targets in a network that try to
924 boot using BOOTP, you may want to avoid that all
925 systems send out BOOTP requests at precisely the same
926 moment (which would happen for instance at recovery
927 from a power failure, when all systems will try to
928 boot, thus flooding the BOOTP server. Defining
929 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
930 inserted before sending out BOOTP requests. The
931 following delays are insterted then:
933 1st BOOTP request: delay 0 ... 1 sec
934 2nd BOOTP request: delay 0 ... 2 sec
935 3rd BOOTP request: delay 0 ... 4 sec
937 BOOTP requests: delay 0 ... 8 sec
939 - DHCP Advanced Options:
942 You can fine tune the DHCP functionality by adding
943 these flags to the CONFIG_BOOTP_MASK define:
945 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
946 serverip from a DHCP server, it is possible that more
947 than one DNS serverip is offered to the client.
948 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
949 serverip will be stored in the additional environment
950 variable "dnsip2". The first DNS serverip is always
951 stored in the variable "dnsip", when CONFIG_BOOTP_DNS
952 is added to the CONFIG_BOOTP_MASK.
954 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
955 to do a dynamic update of a DNS server. To do this, they
956 need the hostname of the DHCP requester.
957 If CONFIG_BOOP_SEND_HOSTNAME is added to the
958 CONFIG_BOOTP_MASK, the content of the "hostname"
959 environment variable is passed as option 12 to
965 The device id used in CDP trigger frames.
967 CONFIG_CDP_DEVICE_ID_PREFIX
969 A two character string which is prefixed to the MAC address
974 A printf format string which contains the ascii name of
975 the port. Normally is set to "eth%d" which sets
976 eth0 for the first ethernet, eth1 for the second etc.
978 CONFIG_CDP_CAPABILITIES
980 A 32bit integer which indicates the device capabilities;
981 0x00000010 for a normal host which does not forwards.
985 An ascii string containing the version of the software.
989 An ascii string containing the name of the platform.
993 A 32bit integer sent on the trigger.
995 CONFIG_CDP_POWER_CONSUMPTION
997 A 16bit integer containing the power consumption of the
998 device in .1 of milliwatts.
1000 CONFIG_CDP_APPLIANCE_VLAN_TYPE
1002 A byte containing the id of the VLAN.
1004 - Status LED: CONFIG_STATUS_LED
1006 Several configurations allow to display the current
1007 status using a LED. For instance, the LED will blink
1008 fast while running U-Boot code, stop blinking as
1009 soon as a reply to a BOOTP request was received, and
1010 start blinking slow once the Linux kernel is running
1011 (supported by a status LED driver in the Linux
1012 kernel). Defining CONFIG_STATUS_LED enables this
1015 - CAN Support: CONFIG_CAN_DRIVER
1017 Defining CONFIG_CAN_DRIVER enables CAN driver support
1018 on those systems that support this (optional)
1019 feature, like the TQM8xxL modules.
1021 - I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C
1023 These enable I2C serial bus commands. Defining either of
1024 (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will
1025 include the appropriate I2C driver for the selected cpu.
1027 This will allow you to use i2c commands at the u-boot
1028 command line (as long as you set CFG_CMD_I2C in
1029 CONFIG_COMMANDS) and communicate with i2c based realtime
1030 clock chips. See common/cmd_i2c.c for a description of the
1031 command line interface.
1033 CONFIG_HARD_I2C selects the CPM hardware driver for I2C.
1035 CONFIG_SOFT_I2C configures u-boot to use a software (aka
1036 bit-banging) driver instead of CPM or similar hardware
1039 There are several other quantities that must also be
1040 defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C.
1042 In both cases you will need to define CFG_I2C_SPEED
1043 to be the frequency (in Hz) at which you wish your i2c bus
1044 to run and CFG_I2C_SLAVE to be the address of this node (ie
1045 the cpu's i2c node address).
1047 Now, the u-boot i2c code for the mpc8xx (cpu/mpc8xx/i2c.c)
1048 sets the cpu up as a master node and so its address should
1049 therefore be cleared to 0 (See, eg, MPC823e User's Manual
1050 p.16-473). So, set CFG_I2C_SLAVE to 0.
1052 That's all that's required for CONFIG_HARD_I2C.
1054 If you use the software i2c interface (CONFIG_SOFT_I2C)
1055 then the following macros need to be defined (examples are
1056 from include/configs/lwmon.h):
1060 (Optional). Any commands necessary to enable the I2C
1061 controller or configure ports.
1063 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
1067 (Only for MPC8260 CPU). The I/O port to use (the code
1068 assumes both bits are on the same port). Valid values
1069 are 0..3 for ports A..D.
1073 The code necessary to make the I2C data line active
1074 (driven). If the data line is open collector, this
1077 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
1081 The code necessary to make the I2C data line tri-stated
1082 (inactive). If the data line is open collector, this
1085 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
1089 Code that returns TRUE if the I2C data line is high,
1092 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
1096 If <bit> is TRUE, sets the I2C data line high. If it
1097 is FALSE, it clears it (low).
1099 eg: #define I2C_SDA(bit) \
1100 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
1101 else immr->im_cpm.cp_pbdat &= ~PB_SDA
1105 If <bit> is TRUE, sets the I2C clock line high. If it
1106 is FALSE, it clears it (low).
1108 eg: #define I2C_SCL(bit) \
1109 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
1110 else immr->im_cpm.cp_pbdat &= ~PB_SCL
1114 This delay is invoked four times per clock cycle so this
1115 controls the rate of data transfer. The data rate thus
1116 is 1 / (I2C_DELAY * 4). Often defined to be something
1119 #define I2C_DELAY udelay(2)
1123 When a board is reset during an i2c bus transfer
1124 chips might think that the current transfer is still
1125 in progress. On some boards it is possible to access
1126 the i2c SCLK line directly, either by using the
1127 processor pin as a GPIO or by having a second pin
1128 connected to the bus. If this option is defined a
1129 custom i2c_init_board() routine in boards/xxx/board.c
1130 is run early in the boot sequence.
1132 - SPI Support: CONFIG_SPI
1134 Enables SPI driver (so far only tested with
1135 SPI EEPROM, also an instance works with Crystal A/D and
1136 D/As on the SACSng board)
1140 Enables extended (16-bit) SPI EEPROM addressing.
1141 (symmetrical to CONFIG_I2C_X)
1145 Enables a software (bit-bang) SPI driver rather than
1146 using hardware support. This is a general purpose
1147 driver that only requires three general I/O port pins
1148 (two outputs, one input) to function. If this is
1149 defined, the board configuration must define several
1150 SPI configuration items (port pins to use, etc). For
1151 an example, see include/configs/sacsng.h.
1153 - FPGA Support: CONFIG_FPGA_COUNT
1155 Specify the number of FPGA devices to support.
1159 Used to specify the types of FPGA devices. For example,
1160 #define CONFIG_FPGA CFG_XILINX_VIRTEX2
1162 CFG_FPGA_PROG_FEEDBACK
1164 Enable printing of hash marks during FPGA configuration.
1168 Enable checks on FPGA configuration interface busy
1169 status by the configuration function. This option
1170 will require a board or device specific function to
1175 If defined, a function that provides delays in the FPGA
1176 configuration driver.
1178 CFG_FPGA_CHECK_CTRLC
1179 Allow Control-C to interrupt FPGA configuration
1181 CFG_FPGA_CHECK_ERROR
1183 Check for configuration errors during FPGA bitfile
1184 loading. For example, abort during Virtex II
1185 configuration if the INIT_B line goes low (which
1186 indicated a CRC error).
1190 Maximum time to wait for the INIT_B line to deassert
1191 after PROB_B has been deasserted during a Virtex II
1192 FPGA configuration sequence. The default time is 500
1197 Maximum time to wait for BUSY to deassert during
1198 Virtex II FPGA configuration. The default is 5 mS.
1200 CFG_FPGA_WAIT_CONFIG
1202 Time to wait after FPGA configuration. The default is
1205 - Configuration Management:
1208 If defined, this string will be added to the U-Boot
1209 version information (U_BOOT_VERSION)
1211 - Vendor Parameter Protection:
1213 U-Boot considers the values of the environment
1214 variables "serial#" (Board Serial Number) and
1215 "ethaddr" (Ethernet Address) to be parameters that
1216 are set once by the board vendor / manufacturer, and
1217 protects these variables from casual modification by
1218 the user. Once set, these variables are read-only,
1219 and write or delete attempts are rejected. You can
1220 change this behviour:
1222 If CONFIG_ENV_OVERWRITE is #defined in your config
1223 file, the write protection for vendor parameters is
1224 completely disabled. Anybody can change or delete
1227 Alternatively, if you #define _both_ CONFIG_ETHADDR
1228 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
1229 ethernet address is installed in the environment,
1230 which can be changed exactly ONCE by the user. [The
1231 serial# is unaffected by this, i. e. it remains
1237 Define this variable to enable the reservation of
1238 "protected RAM", i. e. RAM which is not overwritten
1239 by U-Boot. Define CONFIG_PRAM to hold the number of
1240 kB you want to reserve for pRAM. You can overwrite
1241 this default value by defining an environment
1242 variable "pram" to the number of kB you want to
1243 reserve. Note that the board info structure will
1244 still show the full amount of RAM. If pRAM is
1245 reserved, a new environment variable "mem" will
1246 automatically be defined to hold the amount of
1247 remaining RAM in a form that can be passed as boot
1248 argument to Linux, for instance like that:
1250 setenv bootargs ... mem=\$(mem)
1253 This way you can tell Linux not to use this memory,
1254 either, which results in a memory region that will
1255 not be affected by reboots.
1257 *WARNING* If your board configuration uses automatic
1258 detection of the RAM size, you must make sure that
1259 this memory test is non-destructive. So far, the
1260 following board configurations are known to be
1263 ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL,
1264 HERMES, IP860, RPXlite, LWMON, LANTEC,
1265 PCU_E, FLAGADM, TQM8260
1270 Define this variable to stop the system in case of a
1271 fatal error, so that you have to reset it manually.
1272 This is probably NOT a good idea for an embedded
1273 system where you want to system to reboot
1274 automatically as fast as possible, but it may be
1275 useful during development since you can try to debug
1276 the conditions that lead to the situation.
1278 CONFIG_NET_RETRY_COUNT
1280 This variable defines the number of retries for
1281 network operations like ARP, RARP, TFTP, or BOOTP
1282 before giving up the operation. If not defined, a
1283 default value of 5 is used.
1285 - Command Interpreter:
1288 Enable auto completion of commands using TAB.
1292 Define this variable to enable the "hush" shell (from
1293 Busybox) as command line interpreter, thus enabling
1294 powerful command line syntax like
1295 if...then...else...fi conditionals or `&&' and '||'
1296 constructs ("shell scripts").
1298 If undefined, you get the old, much simpler behaviour
1299 with a somewhat smaller memory footprint.
1304 This defines the secondary prompt string, which is
1305 printed when the command interpreter needs more input
1306 to complete a command. Usually "> ".
1310 In the current implementation, the local variables
1311 space and global environment variables space are
1312 separated. Local variables are those you define by
1313 simply typing `name=value'. To access a local
1314 variable later on, you have write `$name' or
1315 `${name}'; to execute the contents of a variable
1316 directly type `$name' at the command prompt.
1318 Global environment variables are those you use
1319 setenv/printenv to work with. To run a command stored
1320 in such a variable, you need to use the run command,
1321 and you must not use the '$' sign to access them.
1323 To store commands and special characters in a
1324 variable, please use double quotation marks
1325 surrounding the whole text of the variable, instead
1326 of the backslashes before semicolons and special
1329 - Default Environment:
1330 CONFIG_EXTRA_ENV_SETTINGS
1332 Define this to contain any number of null terminated
1333 strings (variable = value pairs) that will be part of
1334 the default environment compiled into the boot image.
1336 For example, place something like this in your
1337 board's config file:
1339 #define CONFIG_EXTRA_ENV_SETTINGS \
1343 Warning: This method is based on knowledge about the
1344 internal format how the environment is stored by the
1345 U-Boot code. This is NOT an official, exported
1346 interface! Although it is unlikely that this format
1347 will change soon, there is no guarantee either.
1348 You better know what you are doing here.
1350 Note: overly (ab)use of the default environment is
1351 discouraged. Make sure to check other ways to preset
1352 the environment like the autoscript function or the
1355 - DataFlash Support:
1356 CONFIG_HAS_DATAFLASH
1358 Defining this option enables DataFlash features and
1359 allows to read/write in Dataflash via the standard
1362 - SystemACE Support:
1365 Adding this option adds support for Xilinx SystemACE
1366 chips attached via some sort of local bus. The address
1367 of the chip must alsh be defined in the
1368 CFG_SYSTEMACE_BASE macro. For example:
1370 #define CONFIG_SYSTEMACE
1371 #define CFG_SYSTEMACE_BASE 0xf0000000
1373 When SystemACE support is added, the "ace" device type
1374 becomes available to the fat commands, i.e. fatls.
1376 - Show boot progress:
1377 CONFIG_SHOW_BOOT_PROGRESS
1379 Defining this option allows to add some board-
1380 specific code (calling a user-provided function
1381 "show_boot_progress(int)") that enables you to show
1382 the system's boot progress on some display (for
1383 example, some LED's) on your board. At the moment,
1384 the following checkpoints are implemented:
1387 1 common/cmd_bootm.c before attempting to boot an image
1388 -1 common/cmd_bootm.c Image header has bad magic number
1389 2 common/cmd_bootm.c Image header has correct magic number
1390 -2 common/cmd_bootm.c Image header has bad checksum
1391 3 common/cmd_bootm.c Image header has correct checksum
1392 -3 common/cmd_bootm.c Image data has bad checksum
1393 4 common/cmd_bootm.c Image data has correct checksum
1394 -4 common/cmd_bootm.c Image is for unsupported architecture
1395 5 common/cmd_bootm.c Architecture check OK
1396 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi, standalone)
1397 6 common/cmd_bootm.c Image Type check OK
1398 -6 common/cmd_bootm.c gunzip uncompression error
1399 -7 common/cmd_bootm.c Unimplemented compression type
1400 7 common/cmd_bootm.c Uncompression OK
1401 -8 common/cmd_bootm.c Wrong Image Type (not kernel, multi, standalone)
1402 8 common/cmd_bootm.c Image Type check OK
1403 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
1404 9 common/cmd_bootm.c Start initial ramdisk verification
1405 -10 common/cmd_bootm.c Ramdisk header has bad magic number
1406 -11 common/cmd_bootm.c Ramdisk header has bad checksum
1407 10 common/cmd_bootm.c Ramdisk header is OK
1408 -12 common/cmd_bootm.c Ramdisk data has bad checksum
1409 11 common/cmd_bootm.c Ramdisk data has correct checksum
1410 12 common/cmd_bootm.c Ramdisk verification complete, start loading
1411 -13 common/cmd_bootm.c Wrong Image Type (not PPC Linux Ramdisk)
1412 13 common/cmd_bootm.c Start multifile image verification
1413 14 common/cmd_bootm.c No initial ramdisk, no multifile, continue.
1414 15 common/cmd_bootm.c All preparation done, transferring control to OS
1416 -30 lib_ppc/board.c Fatal error, hang the system
1417 -31 post/post.c POST test failed, detected by post_output_backlog()
1418 -32 post/post.c POST test failed, detected by post_run_single()
1420 -1 common/cmd_doc.c Bad usage of "doc" command
1421 -1 common/cmd_doc.c No boot device
1422 -1 common/cmd_doc.c Unknown Chip ID on boot device
1423 -1 common/cmd_doc.c Read Error on boot device
1424 -1 common/cmd_doc.c Image header has bad magic number
1426 -1 common/cmd_ide.c Bad usage of "ide" command
1427 -1 common/cmd_ide.c No boot device
1428 -1 common/cmd_ide.c Unknown boot device
1429 -1 common/cmd_ide.c Unknown partition table
1430 -1 common/cmd_ide.c Invalid partition type
1431 -1 common/cmd_ide.c Read Error on boot device
1432 -1 common/cmd_ide.c Image header has bad magic number
1434 -1 common/cmd_nand.c Bad usage of "nand" command
1435 -1 common/cmd_nand.c No boot device
1436 -1 common/cmd_nand.c Unknown Chip ID on boot device
1437 -1 common/cmd_nand.c Read Error on boot device
1438 -1 common/cmd_nand.c Image header has bad magic number
1440 -1 common/env_common.c Environment has a bad CRC, using default
1446 [so far only for SMDK2400 and TRAB boards]
1448 - Modem support endable:
1449 CONFIG_MODEM_SUPPORT
1451 - RTS/CTS Flow control enable:
1454 - Modem debug support:
1455 CONFIG_MODEM_SUPPORT_DEBUG
1457 Enables debugging stuff (char screen[1024], dbg())
1458 for modem support. Useful only with BDI2000.
1460 - Interrupt support (PPC):
1462 There are common interrupt_init() and timer_interrupt()
1463 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
1464 for cpu specific initialization. interrupt_init_cpu()
1465 should set decrementer_count to appropriate value. If
1466 cpu resets decrementer automatically after interrupt
1467 (ppc4xx) it should set decrementer_count to zero.
1468 timer_interrupt() calls timer_interrupt_cpu() for cpu
1469 specific handling. If board has watchdog / status_led
1470 / other_activity_monitor it works automatically from
1471 general timer_interrupt().
1475 In the target system modem support is enabled when a
1476 specific key (key combination) is pressed during
1477 power-on. Otherwise U-Boot will boot normally
1478 (autoboot). The key_pressed() fuction is called from
1479 board_init(). Currently key_pressed() is a dummy
1480 function, returning 1 and thus enabling modem
1483 If there are no modem init strings in the
1484 environment, U-Boot proceed to autoboot; the
1485 previous output (banner, info printfs) will be
1488 See also: doc/README.Modem
1491 Configuration Settings:
1492 -----------------------
1494 - CFG_LONGHELP: Defined when you want long help messages included;
1495 undefine this when you're short of memory.
1497 - CFG_PROMPT: This is what U-Boot prints on the console to
1498 prompt for user input.
1500 - CFG_CBSIZE: Buffer size for input from the Console
1502 - CFG_PBSIZE: Buffer size for Console output
1504 - CFG_MAXARGS: max. Number of arguments accepted for monitor commands
1506 - CFG_BARGSIZE: Buffer size for Boot Arguments which are passed to
1507 the application (usually a Linux kernel) when it is
1510 - CFG_BAUDRATE_TABLE:
1511 List of legal baudrate settings for this board.
1513 - CFG_CONSOLE_INFO_QUIET
1514 Suppress display of console information at boot.
1516 - CFG_CONSOLE_IS_IN_ENV
1517 If the board specific function
1518 extern int overwrite_console (void);
1519 returns 1, the stdin, stderr and stdout are switched to the
1520 serial port, else the settings in the environment are used.
1522 - CFG_CONSOLE_OVERWRITE_ROUTINE
1523 Enable the call to overwrite_console().
1525 - CFG_CONSOLE_ENV_OVERWRITE
1526 Enable overwrite of previous console environment settings.
1528 - CFG_MEMTEST_START, CFG_MEMTEST_END:
1529 Begin and End addresses of the area used by the
1533 Enable an alternate, more extensive memory test.
1535 - CFG_MEMTEST_SCRATCH:
1536 Scratch address used by the alternate memory test
1537 You only need to set this if address zero isn't writeable
1539 - CFG_TFTP_LOADADDR:
1540 Default load address for network file downloads
1542 - CFG_LOADS_BAUD_CHANGE:
1543 Enable temporary baudrate change while serial download
1546 Physical start address of SDRAM. _Must_ be 0 here.
1549 Physical start address of Motherboard I/O (if using a
1553 Physical start address of Flash memory.
1556 Physical start address of boot monitor code (set by
1557 make config files to be same as the text base address
1558 (TEXT_BASE) used when linking) - same as
1559 CFG_FLASH_BASE when booting from flash.
1562 Size of memory reserved for monitor code, used to
1563 determine _at_compile_time_ (!) if the environment is
1564 embedded within the U-Boot image, or in a separate
1568 Size of DRAM reserved for malloc() use.
1571 Maximum size of memory mapped by the startup code of
1572 the Linux kernel; all data that must be processed by
1573 the Linux kernel (bd_info, boot arguments, eventually
1574 initrd image) must be put below this limit.
1576 - CFG_MAX_FLASH_BANKS:
1577 Max number of Flash memory banks
1579 - CFG_MAX_FLASH_SECT:
1580 Max number of sectors on a Flash chip
1582 - CFG_FLASH_ERASE_TOUT:
1583 Timeout for Flash erase operations (in ms)
1585 - CFG_FLASH_WRITE_TOUT:
1586 Timeout for Flash write operations (in ms)
1588 - CFG_FLASH_LOCK_TOUT
1589 Timeout for Flash set sector lock bit operation (in ms)
1591 - CFG_FLASH_UNLOCK_TOUT
1592 Timeout for Flash clear lock bits operation (in ms)
1594 - CFG_FLASH_PROTECTION
1595 If defined, hardware flash sectors protection is used
1596 instead of U-Boot software protection.
1598 - CFG_DIRECT_FLASH_TFTP:
1600 Enable TFTP transfers directly to flash memory;
1601 without this option such a download has to be
1602 performed in two steps: (1) download to RAM, and (2)
1603 copy from RAM to flash.
1605 The two-step approach is usually more reliable, since
1606 you can check if the download worked before you erase
1607 the flash, but in some situations (when sytem RAM is
1608 too limited to allow for a tempory copy of the
1609 downloaded image) this option may be very useful.
1612 Define if the flash driver uses extra elements in the
1613 common flash structure for storing flash geometry.
1615 - CFG_FLASH_CFI_DRIVER
1616 This option also enables the building of the cfi_flash driver
1617 in the drivers directory
1619 - CFG_RX_ETH_BUFFER:
1620 Defines the number of ethernet receive buffers. On some
1621 ethernet controllers it is recommended to set this value
1622 to 8 or even higher (EEPRO100 or 405 EMAC), since all
1623 buffers can be full shortly after enabling the interface
1624 on high ethernet traffic.
1625 Defaults to 4 if not defined.
1627 The following definitions that deal with the placement and management
1628 of environment data (variable area); in general, we support the
1629 following configurations:
1631 - CFG_ENV_IS_IN_FLASH:
1633 Define this if the environment is in flash memory.
1635 a) The environment occupies one whole flash sector, which is
1636 "embedded" in the text segment with the U-Boot code. This
1637 happens usually with "bottom boot sector" or "top boot
1638 sector" type flash chips, which have several smaller
1639 sectors at the start or the end. For instance, such a
1640 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
1641 such a case you would place the environment in one of the
1642 4 kB sectors - with U-Boot code before and after it. With
1643 "top boot sector" type flash chips, you would put the
1644 environment in one of the last sectors, leaving a gap
1645 between U-Boot and the environment.
1649 Offset of environment data (variable area) to the
1650 beginning of flash memory; for instance, with bottom boot
1651 type flash chips the second sector can be used: the offset
1652 for this sector is given here.
1654 CFG_ENV_OFFSET is used relative to CFG_FLASH_BASE.
1658 This is just another way to specify the start address of
1659 the flash sector containing the environment (instead of
1662 - CFG_ENV_SECT_SIZE:
1664 Size of the sector containing the environment.
1667 b) Sometimes flash chips have few, equal sized, BIG sectors.
1668 In such a case you don't want to spend a whole sector for
1673 If you use this in combination with CFG_ENV_IS_IN_FLASH
1674 and CFG_ENV_SECT_SIZE, you can specify to use only a part
1675 of this flash sector for the environment. This saves
1676 memory for the RAM copy of the environment.
1678 It may also save flash memory if you decide to use this
1679 when your environment is "embedded" within U-Boot code,
1680 since then the remainder of the flash sector could be used
1681 for U-Boot code. It should be pointed out that this is
1682 STRONGLY DISCOURAGED from a robustness point of view:
1683 updating the environment in flash makes it always
1684 necessary to erase the WHOLE sector. If something goes
1685 wrong before the contents has been restored from a copy in
1686 RAM, your target system will be dead.
1688 - CFG_ENV_ADDR_REDUND
1691 These settings describe a second storage area used to hold
1692 a redundand copy of the environment data, so that there is
1693 a valid backup copy in case there is a power failure during
1694 a "saveenv" operation.
1696 BE CAREFUL! Any changes to the flash layout, and some changes to the
1697 source code will make it necessary to adapt <board>/u-boot.lds*
1701 - CFG_ENV_IS_IN_NVRAM:
1703 Define this if you have some non-volatile memory device
1704 (NVRAM, battery buffered SRAM) which you want to use for the
1710 These two #defines are used to determin the memory area you
1711 want to use for environment. It is assumed that this memory
1712 can just be read and written to, without any special
1715 BE CAREFUL! The first access to the environment happens quite early
1716 in U-Boot initalization (when we try to get the setting of for the
1717 console baudrate). You *MUST* have mappend your NVRAM area then, or
1720 Please note that even with NVRAM we still use a copy of the
1721 environment in RAM: we could work on NVRAM directly, but we want to
1722 keep settings there always unmodified except somebody uses "saveenv"
1723 to save the current settings.
1726 - CFG_ENV_IS_IN_EEPROM:
1728 Use this if you have an EEPROM or similar serial access
1729 device and a driver for it.
1734 These two #defines specify the offset and size of the
1735 environment area within the total memory of your EEPROM.
1737 - CFG_I2C_EEPROM_ADDR:
1738 If defined, specified the chip address of the EEPROM device.
1739 The default address is zero.
1741 - CFG_EEPROM_PAGE_WRITE_BITS:
1742 If defined, the number of bits used to address bytes in a
1743 single page in the EEPROM device. A 64 byte page, for example
1744 would require six bits.
1746 - CFG_EEPROM_PAGE_WRITE_DELAY_MS:
1747 If defined, the number of milliseconds to delay between
1748 page writes. The default is zero milliseconds.
1750 - CFG_I2C_EEPROM_ADDR_LEN:
1751 The length in bytes of the EEPROM memory array address. Note
1752 that this is NOT the chip address length!
1754 - CFG_I2C_EEPROM_ADDR_OVERFLOW:
1755 EEPROM chips that implement "address overflow" are ones
1756 like Catalyst 24WC04/08/16 which has 9/10/11 bits of
1757 address and the extra bits end up in the "chip address" bit
1758 slots. This makes a 24WC08 (1Kbyte) chip look like four 256
1761 Note that we consider the length of the address field to
1762 still be one byte because the extra address bits are hidden
1763 in the chip address.
1766 The size in bytes of the EEPROM device.
1769 - CFG_ENV_IS_IN_DATAFLASH:
1771 Define this if you have a DataFlash memory device which you
1772 want to use for the environment.
1778 These three #defines specify the offset and size of the
1779 environment area within the total memory of your DataFlash placed
1780 at the specified address.
1783 - CFG_SPI_INIT_OFFSET
1785 Defines offset to the initial SPI buffer area in DPRAM. The
1786 area is used at an early stage (ROM part) if the environment
1787 is configured to reside in the SPI EEPROM: We need a 520 byte
1788 scratch DPRAM area. It is used between the two initialization
1789 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
1790 to be a good choice since it makes it far enough from the
1791 start of the data area as well as from the stack pointer.
1793 Please note that the environment is read-only as long as the monitor
1794 has been relocated to RAM and a RAM copy of the environment has been
1795 created; also, when using EEPROM you will have to use getenv_r()
1796 until then to read environment variables.
1798 The environment is protected by a CRC32 checksum. Before the monitor
1799 is relocated into RAM, as a result of a bad CRC you will be working
1800 with the compiled-in default environment - *silently*!!! [This is
1801 necessary, because the first environment variable we need is the
1802 "baudrate" setting for the console - if we have a bad CRC, we don't
1803 have any device yet where we could complain.]
1805 Note: once the monitor has been relocated, then it will complain if
1806 the default environment is used; a new CRC is computed as soon as you
1807 use the "saveenv" command to store a valid environment.
1809 - CFG_FAULT_ECHO_LINK_DOWN:
1810 Echo the inverted Ethernet link state to the fault LED.
1812 Note: If this option is active, then CFG_FAULT_MII_ADDR
1813 also needs to be defined.
1815 - CFG_FAULT_MII_ADDR:
1816 MII address of the PHY to check for the Ethernet link state.
1818 - CFG_64BIT_VSPRINTF:
1819 Makes vsprintf (and all *printf functions) support printing
1820 of 64bit values by using the L quantifier
1822 - CFG_64BIT_STRTOUL:
1823 Adds simple_strtoull that returns a 64bit value
1825 Low Level (hardware related) configuration options:
1826 ---------------------------------------------------
1828 - CFG_CACHELINE_SIZE:
1829 Cache Line Size of the CPU.
1832 Default address of the IMMR after system reset.
1834 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
1835 and RPXsuper) to be able to adjust the position of
1836 the IMMR register after a reset.
1838 - Floppy Disk Support:
1839 CFG_FDC_DRIVE_NUMBER
1841 the default drive number (default value 0)
1845 defines the spacing between fdc chipset registers
1850 defines the offset of register from address. It
1851 depends on which part of the data bus is connected to
1852 the fdc chipset. (default value 0)
1854 If CFG_ISA_IO_STRIDE CFG_ISA_IO_OFFSET and
1855 CFG_FDC_DRIVE_NUMBER are undefined, they take their
1858 if CFG_FDC_HW_INIT is defined, then the function
1859 fdc_hw_init() is called at the beginning of the FDC
1860 setup. fdc_hw_init() must be provided by the board
1861 source code. It is used to make hardware dependant
1864 - CFG_IMMR: Physical address of the Internal Memory Mapped
1865 Register; DO NOT CHANGE! (11-4)
1866 [MPC8xx systems only]
1868 - CFG_INIT_RAM_ADDR:
1870 Start address of memory area that can be used for
1871 initial data and stack; please note that this must be
1872 writable memory that is working WITHOUT special
1873 initialization, i. e. you CANNOT use normal RAM which
1874 will become available only after programming the
1875 memory controller and running certain initialization
1878 U-Boot uses the following memory types:
1879 - MPC8xx and MPC8260: IMMR (internal memory of the CPU)
1880 - MPC824X: data cache
1881 - PPC4xx: data cache
1883 - CFG_GBL_DATA_OFFSET:
1885 Offset of the initial data structure in the memory
1886 area defined by CFG_INIT_RAM_ADDR. Usually
1887 CFG_GBL_DATA_OFFSET is chosen such that the initial
1888 data is located at the end of the available space
1889 (sometimes written as (CFG_INIT_RAM_END -
1890 CFG_INIT_DATA_SIZE), and the initial stack is just
1891 below that area (growing from (CFG_INIT_RAM_ADDR +
1892 CFG_GBL_DATA_OFFSET) downward.
1895 On the MPC824X (or other systems that use the data
1896 cache for initial memory) the address chosen for
1897 CFG_INIT_RAM_ADDR is basically arbitrary - it must
1898 point to an otherwise UNUSED address space between
1899 the top of RAM and the start of the PCI space.
1901 - CFG_SIUMCR: SIU Module Configuration (11-6)
1903 - CFG_SYPCR: System Protection Control (11-9)
1905 - CFG_TBSCR: Time Base Status and Control (11-26)
1907 - CFG_PISCR: Periodic Interrupt Status and Control (11-31)
1909 - CFG_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30)
1911 - CFG_SCCR: System Clock and reset Control Register (15-27)
1913 - CFG_OR_TIMING_SDRAM:
1917 periodic timer for refresh
1919 - CFG_DER: Debug Event Register (37-47)
1921 - FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CFG_REMAP_OR_AM,
1922 CFG_PRELIM_OR_AM, CFG_OR_TIMING_FLASH, CFG_OR0_REMAP,
1923 CFG_OR0_PRELIM, CFG_BR0_PRELIM, CFG_OR1_REMAP, CFG_OR1_PRELIM,
1925 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
1927 - SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
1928 CFG_OR_TIMING_SDRAM, CFG_OR2_PRELIM, CFG_BR2_PRELIM,
1929 CFG_OR3_PRELIM, CFG_BR3_PRELIM:
1930 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
1932 - CFG_MAMR_PTA, CFG_MPTPR_2BK_4K, CFG_MPTPR_1BK_4K, CFG_MPTPR_2BK_8K,
1933 CFG_MPTPR_1BK_8K, CFG_MAMR_8COL, CFG_MAMR_9COL:
1934 Machine Mode Register and Memory Periodic Timer
1935 Prescaler definitions (SDRAM timing)
1937 - CFG_I2C_UCODE_PATCH, CFG_I2C_DPMEM_OFFSET [0x1FC0]:
1938 enable I2C microcode relocation patch (MPC8xx);
1939 define relocation offset in DPRAM [DSP2]
1941 - CFG_SPI_UCODE_PATCH, CFG_SPI_DPMEM_OFFSET [0x1FC0]:
1942 enable SPI microcode relocation patch (MPC8xx);
1943 define relocation offset in DPRAM [SCC4]
1946 Use OSCM clock mode on MBX8xx board. Be careful,
1947 wrong setting might damage your board. Read
1948 doc/README.MBX before setting this variable!
1950 - CFG_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
1951 Offset of the bootmode word in DPRAM used by post
1952 (Power On Self Tests). This definition overrides
1953 #define'd default value in commproc.h resp.
1956 - CFG_PCI_SLV_MEM_LOCAL, CFG_PCI_SLV_MEM_BUS, CFG_PICMR0_MASK_ATTRIB,
1957 CFG_PCI_MSTR0_LOCAL, CFG_PCIMSK0_MASK, CFG_PCI_MSTR1_LOCAL,
1958 CFG_PCIMSK1_MASK, CFG_PCI_MSTR_MEM_LOCAL, CFG_PCI_MSTR_MEM_BUS,
1959 CFG_CPU_PCI_MEM_START, CFG_PCI_MSTR_MEM_SIZE, CFG_POCMR0_MASK_ATTRIB,
1960 CFG_PCI_MSTR_MEMIO_LOCAL, CFG_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
1961 CFG_PCI_MSTR_MEMIO_SIZE, CFG_POCMR1_MASK_ATTRIB, CFG_PCI_MSTR_IO_LOCAL,
1962 CFG_PCI_MSTR_IO_BUS, CFG_CPU_PCI_IO_START, CFG_PCI_MSTR_IO_SIZE,
1963 CFG_POCMR2_MASK_ATTRIB: (MPC826x only)
1964 Overrides the default PCI memory map in cpu/mpc8260/pci.c if set.
1966 - CONFIG_ETHER_ON_FEC[12]
1967 Define to enable FEC[12] on a 8xx series processor.
1969 - CONFIG_FEC[12]_PHY
1970 Define to the hardcoded PHY address which corresponds
1971 to the given FEC; i. e.
1972 #define CONFIG_FEC1_PHY 4
1973 means that the PHY with address 4 is connected to FEC1
1975 When set to -1, means to probe for first available.
1977 - CONFIG_FEC[12]_PHY_NORXERR
1978 The PHY does not have a RXERR line (RMII only).
1979 (so program the FEC to ignore it).
1982 Enable RMII mode for all FECs.
1983 Note that this is a global option, we can't
1984 have one FEC in standard MII mode and another in RMII mode.
1986 - CONFIG_CRC32_VERIFY
1987 Add a verify option to the crc32 command.
1990 => crc32 -v <address> <count> <crc32>
1992 Where address/count indicate a memory area
1993 and crc32 is the correct crc32 which the
1996 Building the Software:
1997 ======================
1999 Building U-Boot has been tested in native PPC environments (on a
2000 PowerBook G3 running LinuxPPC 2000) and in cross environments
2001 (running RedHat 6.x and 7.x Linux on x86, Solaris 2.6 on a SPARC, and
2004 If you are not using a native PPC environment, it is assumed that you
2005 have the GNU cross compiling tools available in your path and named
2006 with a prefix of "powerpc-linux-". If this is not the case, (e.g. if
2007 you are using Monta Vista's Hard Hat Linux CDK 1.2) you must change
2008 the definition of CROSS_COMPILE in Makefile. For HHL on a 4xx CPU,
2011 CROSS_COMPILE = ppc_4xx-
2014 U-Boot is intended to be simple to build. After installing the
2015 sources you must configure U-Boot for one specific board type. This
2020 where "NAME_config" is the name of one of the existing
2021 configurations; the following names are supported:
2023 ADCIOP_config ADS860_config AR405_config
2024 at91rm9200dk_config CANBT_config cmi_mpc5xx_config
2025 cogent_common_config cogent_mpc8260_config cogent_mpc8xx_config
2026 CPCI405_config CPCIISER4_config CU824_config
2027 DUET_ADS_config EBONY_config ELPT860_config
2028 ESTEEM192E_config ETX094_config FADS823_config
2029 FADS850SAR_config FADS860T_config FPS850L_config
2030 FPS860L_config GEN860T_config GENIETV_config
2031 GTH_config hermes_config hymod_config
2032 IP860_config IVML24_config IVMS8_config
2033 JSE_config LANTEC_config lwmon_config
2034 MBX860T_config MBX_config MPC8260ADS_config
2035 MPC8540ADS_config MPC8560ADS_config NETVIA_config
2036 omap1510inn_config omap1610h2_config omap1610inn_config
2037 pcu_e_config PIP405_config QS823_config
2038 QS850_config QS860T_config RPXlite_config
2039 RPXsuper_config rsdproto_config Sandpoint8240_config
2040 sbc8260_config SM850_config SPD823TS_config
2041 stxgp3_config SXNI855T_config TQM823L_config
2042 TQM850L_config TQM855L_config TQM860L_config
2043 WALNUT405_config ZPC1900_config
2045 Note: for some board special configuration names may exist; check if
2046 additional information is available from the board vendor; for
2047 instance, the TQM823L systems are available without (standard)
2048 or with LCD support. You can select such additional "features"
2049 when chosing the configuration, i. e.
2052 - will configure for a plain TQM823L, i. e. no LCD support
2054 make TQM823L_LCD_config
2055 - will configure for a TQM823L with U-Boot console on LCD
2060 Finally, type "make all", and you should get some working U-Boot
2061 images ready for download to / installation on your system:
2063 - "u-boot.bin" is a raw binary image
2064 - "u-boot" is an image in ELF binary format
2065 - "u-boot.srec" is in Motorola S-Record format
2068 Please be aware that the Makefiles assume you are using GNU make, so
2069 for instance on NetBSD you might need to use "gmake" instead of
2073 If the system board that you have is not listed, then you will need
2074 to port U-Boot to your hardware platform. To do this, follow these
2077 1. Add a new configuration option for your board to the toplevel
2078 "Makefile" and to the "MAKEALL" script, using the existing
2079 entries as examples. Note that here and at many other places
2080 boards and other names are listed in alphabetical sort order. Please
2082 2. Create a new directory to hold your board specific code. Add any
2083 files you need. In your board directory, you will need at least
2084 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
2085 3. Create a new configuration file "include/configs/<board>.h" for
2087 3. If you're porting U-Boot to a new CPU, then also create a new
2088 directory to hold your CPU specific code. Add any files you need.
2089 4. Run "make <board>_config" with your new name.
2090 5. Type "make", and you should get a working "u-boot.srec" file
2091 to be installed on your target system.
2092 6. Debug and solve any problems that might arise.
2093 [Of course, this last step is much harder than it sounds.]
2096 Testing of U-Boot Modifications, Ports to New Hardware, etc.:
2097 ==============================================================
2099 If you have modified U-Boot sources (for instance added a new board
2100 or support for new devices, a new CPU, etc.) you are expected to
2101 provide feedback to the other developers. The feedback normally takes
2102 the form of a "patch", i. e. a context diff against a certain (latest
2103 official or latest in CVS) version of U-Boot sources.
2105 But before you submit such a patch, please verify that your modifi-
2106 cation did not break existing code. At least make sure that *ALL* of
2107 the supported boards compile WITHOUT ANY compiler warnings. To do so,
2108 just run the "MAKEALL" script, which will configure and build U-Boot
2109 for ALL supported system. Be warned, this will take a while. You can
2110 select which (cross) compiler to use by passing a `CROSS_COMPILE'
2111 environment variable to the script, i. e. to use the cross tools from
2112 MontaVista's Hard Hat Linux you can type
2114 CROSS_COMPILE=ppc_8xx- MAKEALL
2116 or to build on a native PowerPC system you can type
2118 CROSS_COMPILE=' ' MAKEALL
2120 See also "U-Boot Porting Guide" below.
2123 Monitor Commands - Overview:
2124 ============================
2126 go - start application at address 'addr'
2127 run - run commands in an environment variable
2128 bootm - boot application image from memory
2129 bootp - boot image via network using BootP/TFTP protocol
2130 tftpboot- boot image via network using TFTP protocol
2131 and env variables "ipaddr" and "serverip"
2132 (and eventually "gatewayip")
2133 rarpboot- boot image via network using RARP/TFTP protocol
2134 diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
2135 loads - load S-Record file over serial line
2136 loadb - load binary file over serial line (kermit mode)
2138 mm - memory modify (auto-incrementing)
2139 nm - memory modify (constant address)
2140 mw - memory write (fill)
2142 cmp - memory compare
2143 crc32 - checksum calculation
2144 imd - i2c memory display
2145 imm - i2c memory modify (auto-incrementing)
2146 inm - i2c memory modify (constant address)
2147 imw - i2c memory write (fill)
2148 icrc32 - i2c checksum calculation
2149 iprobe - probe to discover valid I2C chip addresses
2150 iloop - infinite loop on address range
2151 isdram - print SDRAM configuration information
2152 sspi - SPI utility commands
2153 base - print or set address offset
2154 printenv- print environment variables
2155 setenv - set environment variables
2156 saveenv - save environment variables to persistent storage
2157 protect - enable or disable FLASH write protection
2158 erase - erase FLASH memory
2159 flinfo - print FLASH memory information
2160 bdinfo - print Board Info structure
2161 iminfo - print header information for application image
2162 coninfo - print console devices and informations
2163 ide - IDE sub-system
2164 loop - infinite loop on address range
2165 mtest - simple RAM test
2166 icache - enable or disable instruction cache
2167 dcache - enable or disable data cache
2168 reset - Perform RESET of the CPU
2169 echo - echo args to console
2170 version - print monitor version
2171 help - print online help
2172 ? - alias for 'help'
2175 Monitor Commands - Detailed Description:
2176 ========================================
2180 For now: just type "help <command>".
2183 Environment Variables:
2184 ======================
2186 U-Boot supports user configuration using Environment Variables which
2187 can be made persistent by saving to Flash memory.
2189 Environment Variables are set using "setenv", printed using
2190 "printenv", and saved to Flash using "saveenv". Using "setenv"
2191 without a value can be used to delete a variable from the
2192 environment. As long as you don't save the environment you are
2193 working with an in-memory copy. In case the Flash area containing the
2194 environment is erased by accident, a default environment is provided.
2196 Some configuration options can be set using Environment Variables:
2198 baudrate - see CONFIG_BAUDRATE
2200 bootdelay - see CONFIG_BOOTDELAY
2202 bootcmd - see CONFIG_BOOTCOMMAND
2204 bootargs - Boot arguments when booting an RTOS image
2206 bootfile - Name of the image to load with TFTP
2208 autoload - if set to "no" (any string beginning with 'n'),
2209 "bootp" will just load perform a lookup of the
2210 configuration from the BOOTP server, but not try to
2211 load any image using TFTP
2213 autostart - if set to "yes", an image loaded using the "bootp",
2214 "rarpboot", "tftpboot" or "diskboot" commands will
2215 be automatically started (by internally calling
2218 If set to "no", a standalone image passed to the
2219 "bootm" command will be copied to the load address
2220 (and eventually uncompressed), but NOT be started.
2221 This can be used to load and uncompress arbitrary
2224 initrd_high - restrict positioning of initrd images:
2225 If this variable is not set, initrd images will be
2226 copied to the highest possible address in RAM; this
2227 is usually what you want since it allows for
2228 maximum initrd size. If for some reason you want to
2229 make sure that the initrd image is loaded below the
2230 CFG_BOOTMAPSZ limit, you can set this environment
2231 variable to a value of "no" or "off" or "0".
2232 Alternatively, you can set it to a maximum upper
2233 address to use (U-Boot will still check that it
2234 does not overwrite the U-Boot stack and data).
2236 For instance, when you have a system with 16 MB
2237 RAM, and want to reserve 4 MB from use by Linux,
2238 you can do this by adding "mem=12M" to the value of
2239 the "bootargs" variable. However, now you must make
2240 sure that the initrd image is placed in the first
2241 12 MB as well - this can be done with
2243 setenv initrd_high 00c00000
2245 If you set initrd_high to 0xFFFFFFFF, this is an
2246 indication to U-Boot that all addresses are legal
2247 for the Linux kernel, including addresses in flash
2248 memory. In this case U-Boot will NOT COPY the
2249 ramdisk at all. This may be useful to reduce the
2250 boot time on your system, but requires that this
2251 feature is supported by your Linux kernel.
2253 ipaddr - IP address; needed for tftpboot command
2255 loadaddr - Default load address for commands like "bootp",
2256 "rarpboot", "tftpboot", "loadb" or "diskboot"
2258 loads_echo - see CONFIG_LOADS_ECHO
2260 serverip - TFTP server IP address; needed for tftpboot command
2262 bootretry - see CONFIG_BOOT_RETRY_TIME
2264 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
2266 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
2268 ethprime - When CONFIG_NET_MULTI is enabled controls which
2269 interface is used first.
2271 ethact - When CONFIG_NET_MULTI is enabled controls which
2272 interface is currently active. For example you
2273 can do the following
2275 => setenv ethact FEC ETHERNET
2276 => ping 192.168.0.1 # traffic sent on FEC ETHERNET
2277 => setenv ethact SCC ETHERNET
2278 => ping 10.0.0.1 # traffic sent on SCC ETHERNET
2280 netretry - When set to "no" each network operation will
2281 either succeed or fail without retrying.
2282 When set to "once" the network operation will
2283 fail when all the available network interfaces
2284 are tried once without success.
2285 Useful on scripts which control the retry operation
2288 vlan - When set to a value < 4095 the traffic over
2289 ethernet is encapsulated/received over 802.1q
2292 The following environment variables may be used and automatically
2293 updated by the network boot commands ("bootp" and "rarpboot"),
2294 depending the information provided by your boot server:
2296 bootfile - see above
2297 dnsip - IP address of your Domain Name Server
2298 dnsip2 - IP address of your secondary Domain Name Server
2299 gatewayip - IP address of the Gateway (Router) to use
2300 hostname - Target hostname
2302 netmask - Subnet Mask
2303 rootpath - Pathname of the root filesystem on the NFS server
2304 serverip - see above
2307 There are two special Environment Variables:
2309 serial# - contains hardware identification information such
2310 as type string and/or serial number
2311 ethaddr - Ethernet address
2313 These variables can be set only once (usually during manufacturing of
2314 the board). U-Boot refuses to delete or overwrite these variables
2315 once they have been set once.
2318 Further special Environment Variables:
2320 ver - Contains the U-Boot version string as printed
2321 with the "version" command. This variable is
2322 readonly (see CONFIG_VERSION_VARIABLE).
2325 Please note that changes to some configuration parameters may take
2326 only effect after the next boot (yes, that's just like Windoze :-).
2329 Command Line Parsing:
2330 =====================
2332 There are two different command line parsers available with U-Boot:
2333 the old "simple" one, and the much more powerful "hush" shell:
2335 Old, simple command line parser:
2336 --------------------------------
2338 - supports environment variables (through setenv / saveenv commands)
2339 - several commands on one line, separated by ';'
2340 - variable substitution using "... $(name) ..." syntax
2341 - special characters ('$', ';') can be escaped by prefixing with '\',
2343 setenv bootcmd bootm \$(address)
2344 - You can also escape text by enclosing in single apostrophes, for example:
2345 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
2350 - similar to Bourne shell, with control structures like
2351 if...then...else...fi, for...do...done; while...do...done,
2352 until...do...done, ...
2353 - supports environment ("global") variables (through setenv / saveenv
2354 commands) and local shell variables (through standard shell syntax
2355 "name=value"); only environment variables can be used with "run"
2361 (1) If a command line (or an environment variable executed by a "run"
2362 command) contains several commands separated by semicolon, and
2363 one of these commands fails, then the remaining commands will be
2366 (2) If you execute several variables with one call to run (i. e.
2367 calling run with a list af variables as arguments), any failing
2368 command will cause "run" to terminate, i. e. the remaining
2369 variables are not executed.
2371 Note for Redundant Ethernet Interfaces:
2372 =======================================
2374 Some boards come with redundant ethernet interfaces; U-Boot supports
2375 such configurations and is capable of automatic selection of a
2376 "working" interface when needed. MAC assignment works as follows:
2378 Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
2379 MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
2380 "eth1addr" (=>eth1), "eth2addr", ...
2382 If the network interface stores some valid MAC address (for instance
2383 in SROM), this is used as default address if there is NO correspon-
2384 ding setting in the environment; if the corresponding environment
2385 variable is set, this overrides the settings in the card; that means:
2387 o If the SROM has a valid MAC address, and there is no address in the
2388 environment, the SROM's address is used.
2390 o If there is no valid address in the SROM, and a definition in the
2391 environment exists, then the value from the environment variable is
2394 o If both the SROM and the environment contain a MAC address, and
2395 both addresses are the same, this MAC address is used.
2397 o If both the SROM and the environment contain a MAC address, and the
2398 addresses differ, the value from the environment is used and a
2401 o If neither SROM nor the environment contain a MAC address, an error
2408 The "boot" commands of this monitor operate on "image" files which
2409 can be basicly anything, preceeded by a special header; see the
2410 definitions in include/image.h for details; basicly, the header
2411 defines the following image properties:
2413 * Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
2414 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
2415 LynxOS, pSOS, QNX, RTEMS, ARTOS;
2416 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, ARTOS, LynxOS).
2417 * Target CPU Architecture (Provisions for Alpha, ARM, Intel x86,
2418 IA64, MIPS, NIOS, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
2419 Currently supported: ARM, Intel x86, MIPS, NIOS, PowerPC).
2420 * Compression Type (uncompressed, gzip, bzip2)
2426 The header is marked by a special Magic Number, and both the header
2427 and the data portions of the image are secured against corruption by
2434 Although U-Boot should support any OS or standalone application
2435 easily, the main focus has always been on Linux during the design of
2438 U-Boot includes many features that so far have been part of some
2439 special "boot loader" code within the Linux kernel. Also, any
2440 "initrd" images to be used are no longer part of one big Linux image;
2441 instead, kernel and "initrd" are separate images. This implementation
2442 serves several purposes:
2444 - the same features can be used for other OS or standalone
2445 applications (for instance: using compressed images to reduce the
2446 Flash memory footprint)
2448 - it becomes much easier to port new Linux kernel versions because
2449 lots of low-level, hardware dependent stuff are done by U-Boot
2451 - the same Linux kernel image can now be used with different "initrd"
2452 images; of course this also means that different kernel images can
2453 be run with the same "initrd". This makes testing easier (you don't
2454 have to build a new "zImage.initrd" Linux image when you just
2455 change a file in your "initrd"). Also, a field-upgrade of the
2456 software is easier now.
2462 Porting Linux to U-Boot based systems:
2463 ---------------------------------------
2465 U-Boot cannot save you from doing all the necessary modifications to
2466 configure the Linux device drivers for use with your target hardware
2467 (no, we don't intend to provide a full virtual machine interface to
2470 But now you can ignore ALL boot loader code (in arch/ppc/mbxboot).
2472 Just make sure your machine specific header file (for instance
2473 include/asm-ppc/tqm8xx.h) includes the same definition of the Board
2474 Information structure as we define in include/u-boot.h, and make
2475 sure that your definition of IMAP_ADDR uses the same value as your
2476 U-Boot configuration in CFG_IMMR.
2479 Configuring the Linux kernel:
2480 -----------------------------
2482 No specific requirements for U-Boot. Make sure you have some root
2483 device (initial ramdisk, NFS) for your target system.
2486 Building a Linux Image:
2487 -----------------------
2489 With U-Boot, "normal" build targets like "zImage" or "bzImage" are
2490 not used. If you use recent kernel source, a new build target
2491 "uImage" will exist which automatically builds an image usable by
2492 U-Boot. Most older kernels also have support for a "pImage" target,
2493 which was introduced for our predecessor project PPCBoot and uses a
2494 100% compatible format.
2503 The "uImage" build target uses a special tool (in 'tools/mkimage') to
2504 encapsulate a compressed Linux kernel image with header information,
2505 CRC32 checksum etc. for use with U-Boot. This is what we are doing:
2507 * build a standard "vmlinux" kernel image (in ELF binary format):
2509 * convert the kernel into a raw binary image:
2511 ${CROSS_COMPILE}-objcopy -O binary \
2512 -R .note -R .comment \
2513 -S vmlinux linux.bin
2515 * compress the binary image:
2519 * package compressed binary image for U-Boot:
2521 mkimage -A ppc -O linux -T kernel -C gzip \
2522 -a 0 -e 0 -n "Linux Kernel Image" \
2523 -d linux.bin.gz uImage
2526 The "mkimage" tool can also be used to create ramdisk images for use
2527 with U-Boot, either separated from the Linux kernel image, or
2528 combined into one file. "mkimage" encapsulates the images with a 64
2529 byte header containing information about target architecture,
2530 operating system, image type, compression method, entry points, time
2531 stamp, CRC32 checksums, etc.
2533 "mkimage" can be called in two ways: to verify existing images and
2534 print the header information, or to build new images.
2536 In the first form (with "-l" option) mkimage lists the information
2537 contained in the header of an existing U-Boot image; this includes
2538 checksum verification:
2540 tools/mkimage -l image
2541 -l ==> list image header information
2543 The second form (with "-d" option) is used to build a U-Boot image
2544 from a "data file" which is used as image payload:
2546 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
2547 -n name -d data_file image
2548 -A ==> set architecture to 'arch'
2549 -O ==> set operating system to 'os'
2550 -T ==> set image type to 'type'
2551 -C ==> set compression type 'comp'
2552 -a ==> set load address to 'addr' (hex)
2553 -e ==> set entry point to 'ep' (hex)
2554 -n ==> set image name to 'name'
2555 -d ==> use image data from 'datafile'
2557 Right now, all Linux kernels use the same load address (0x00000000),
2558 but the entry point address depends on the kernel version:
2560 - 2.2.x kernels have the entry point at 0x0000000C,
2561 - 2.3.x and later kernels have the entry point at 0x00000000.
2563 So a typical call to build a U-Boot image would read:
2565 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
2566 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
2567 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz \
2568 > examples/uImage.TQM850L
2569 Image Name: 2.4.4 kernel for TQM850L
2570 Created: Wed Jul 19 02:34:59 2000
2571 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2572 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
2573 Load Address: 0x00000000
2574 Entry Point: 0x00000000
2576 To verify the contents of the image (or check for corruption):
2578 -> tools/mkimage -l examples/uImage.TQM850L
2579 Image Name: 2.4.4 kernel for TQM850L
2580 Created: Wed Jul 19 02:34:59 2000
2581 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2582 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
2583 Load Address: 0x00000000
2584 Entry Point: 0x00000000
2586 NOTE: for embedded systems where boot time is critical you can trade
2587 speed for memory and install an UNCOMPRESSED image instead: this
2588 needs more space in Flash, but boots much faster since it does not
2589 need to be uncompressed:
2591 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz
2592 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
2593 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
2594 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux \
2595 > examples/uImage.TQM850L-uncompressed
2596 Image Name: 2.4.4 kernel for TQM850L
2597 Created: Wed Jul 19 02:34:59 2000
2598 Image Type: PowerPC Linux Kernel Image (uncompressed)
2599 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
2600 Load Address: 0x00000000
2601 Entry Point: 0x00000000
2604 Similar you can build U-Boot images from a 'ramdisk.image.gz' file
2605 when your kernel is intended to use an initial ramdisk:
2607 -> tools/mkimage -n 'Simple Ramdisk Image' \
2608 > -A ppc -O linux -T ramdisk -C gzip \
2609 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
2610 Image Name: Simple Ramdisk Image
2611 Created: Wed Jan 12 14:01:50 2000
2612 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2613 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
2614 Load Address: 0x00000000
2615 Entry Point: 0x00000000
2618 Installing a Linux Image:
2619 -------------------------
2621 To downloading a U-Boot image over the serial (console) interface,
2622 you must convert the image to S-Record format:
2624 objcopy -I binary -O srec examples/image examples/image.srec
2626 The 'objcopy' does not understand the information in the U-Boot
2627 image header, so the resulting S-Record file will be relative to
2628 address 0x00000000. To load it to a given address, you need to
2629 specify the target address as 'offset' parameter with the 'loads'
2632 Example: install the image to address 0x40100000 (which on the
2633 TQM8xxL is in the first Flash bank):
2635 => erase 40100000 401FFFFF
2641 ## Ready for S-Record download ...
2642 ~>examples/image.srec
2643 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
2645 15989 15990 15991 15992
2646 [file transfer complete]
2648 ## Start Addr = 0x00000000
2651 You can check the success of the download using the 'iminfo' command;
2652 this includes a checksum verification so you can be sure no data
2653 corruption happened:
2657 ## Checking Image at 40100000 ...
2658 Image Name: 2.2.13 for initrd on TQM850L
2659 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2660 Data Size: 335725 Bytes = 327 kB = 0 MB
2661 Load Address: 00000000
2662 Entry Point: 0000000c
2663 Verifying Checksum ... OK
2669 The "bootm" command is used to boot an application that is stored in
2670 memory (RAM or Flash). In case of a Linux kernel image, the contents
2671 of the "bootargs" environment variable is passed to the kernel as
2672 parameters. You can check and modify this variable using the
2673 "printenv" and "setenv" commands:
2676 => printenv bootargs
2677 bootargs=root=/dev/ram
2679 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2681 => printenv bootargs
2682 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2685 ## Booting Linux kernel at 40020000 ...
2686 Image Name: 2.2.13 for NFS on TQM850L
2687 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2688 Data Size: 381681 Bytes = 372 kB = 0 MB
2689 Load Address: 00000000
2690 Entry Point: 0000000c
2691 Verifying Checksum ... OK
2692 Uncompressing Kernel Image ... OK
2693 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
2694 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2695 time_init: decrementer frequency = 187500000/60
2696 Calibrating delay loop... 49.77 BogoMIPS
2697 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
2700 If you want to boot a Linux kernel with initial ram disk, you pass
2701 the memory addresses of both the kernel and the initrd image (PPBCOOT
2702 format!) to the "bootm" command:
2704 => imi 40100000 40200000
2706 ## Checking Image at 40100000 ...
2707 Image Name: 2.2.13 for initrd on TQM850L
2708 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2709 Data Size: 335725 Bytes = 327 kB = 0 MB
2710 Load Address: 00000000
2711 Entry Point: 0000000c
2712 Verifying Checksum ... OK
2714 ## Checking Image at 40200000 ...
2715 Image Name: Simple Ramdisk Image
2716 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2717 Data Size: 566530 Bytes = 553 kB = 0 MB
2718 Load Address: 00000000
2719 Entry Point: 00000000
2720 Verifying Checksum ... OK
2722 => bootm 40100000 40200000
2723 ## Booting Linux kernel at 40100000 ...
2724 Image Name: 2.2.13 for initrd on TQM850L
2725 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2726 Data Size: 335725 Bytes = 327 kB = 0 MB
2727 Load Address: 00000000
2728 Entry Point: 0000000c
2729 Verifying Checksum ... OK
2730 Uncompressing Kernel Image ... OK
2731 ## Loading RAMDisk Image at 40200000 ...
2732 Image Name: Simple Ramdisk Image
2733 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2734 Data Size: 566530 Bytes = 553 kB = 0 MB
2735 Load Address: 00000000
2736 Entry Point: 00000000
2737 Verifying Checksum ... OK
2738 Loading Ramdisk ... OK
2739 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
2740 Boot arguments: root=/dev/ram
2741 time_init: decrementer frequency = 187500000/60
2742 Calibrating delay loop... 49.77 BogoMIPS
2744 RAMDISK: Compressed image found at block 0
2745 VFS: Mounted root (ext2 filesystem).
2749 More About U-Boot Image Types:
2750 ------------------------------
2752 U-Boot supports the following image types:
2754 "Standalone Programs" are directly runnable in the environment
2755 provided by U-Boot; it is expected that (if they behave
2756 well) you can continue to work in U-Boot after return from
2757 the Standalone Program.
2758 "OS Kernel Images" are usually images of some Embedded OS which
2759 will take over control completely. Usually these programs
2760 will install their own set of exception handlers, device
2761 drivers, set up the MMU, etc. - this means, that you cannot
2762 expect to re-enter U-Boot except by resetting the CPU.
2763 "RAMDisk Images" are more or less just data blocks, and their
2764 parameters (address, size) are passed to an OS kernel that is
2766 "Multi-File Images" contain several images, typically an OS
2767 (Linux) kernel image and one or more data images like
2768 RAMDisks. This construct is useful for instance when you want
2769 to boot over the network using BOOTP etc., where the boot
2770 server provides just a single image file, but you want to get
2771 for instance an OS kernel and a RAMDisk image.
2773 "Multi-File Images" start with a list of image sizes, each
2774 image size (in bytes) specified by an "uint32_t" in network
2775 byte order. This list is terminated by an "(uint32_t)0".
2776 Immediately after the terminating 0 follow the images, one by
2777 one, all aligned on "uint32_t" boundaries (size rounded up to
2778 a multiple of 4 bytes).
2780 "Firmware Images" are binary images containing firmware (like
2781 U-Boot or FPGA images) which usually will be programmed to
2784 "Script files" are command sequences that will be executed by
2785 U-Boot's command interpreter; this feature is especially
2786 useful when you configure U-Boot to use a real shell (hush)
2787 as command interpreter.
2793 One of the features of U-Boot is that you can dynamically load and
2794 run "standalone" applications, which can use some resources of
2795 U-Boot like console I/O functions or interrupt services.
2797 Two simple examples are included with the sources:
2802 'examples/hello_world.c' contains a small "Hello World" Demo
2803 application; it is automatically compiled when you build U-Boot.
2804 It's configured to run at address 0x00040004, so you can play with it
2808 ## Ready for S-Record download ...
2809 ~>examples/hello_world.srec
2810 1 2 3 4 5 6 7 8 9 10 11 ...
2811 [file transfer complete]
2813 ## Start Addr = 0x00040004
2815 => go 40004 Hello World! This is a test.
2816 ## Starting application at 0x00040004 ...
2827 Hit any key to exit ...
2829 ## Application terminated, rc = 0x0
2831 Another example, which demonstrates how to register a CPM interrupt
2832 handler with the U-Boot code, can be found in 'examples/timer.c'.
2833 Here, a CPM timer is set up to generate an interrupt every second.
2834 The interrupt service routine is trivial, just printing a '.'
2835 character, but this is just a demo program. The application can be
2836 controlled by the following keys:
2838 ? - print current values og the CPM Timer registers
2839 b - enable interrupts and start timer
2840 e - stop timer and disable interrupts
2841 q - quit application
2844 ## Ready for S-Record download ...
2845 ~>examples/timer.srec
2846 1 2 3 4 5 6 7 8 9 10 11 ...
2847 [file transfer complete]
2849 ## Start Addr = 0x00040004
2852 ## Starting application at 0x00040004 ...
2855 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
2858 [q, b, e, ?] Set interval 1000000 us
2861 [q, b, e, ?] ........
2862 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
2865 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
2868 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
2871 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
2873 [q, b, e, ?] ...Stopping timer
2875 [q, b, e, ?] ## Application terminated, rc = 0x0
2881 Over time, many people have reported problems when trying to use the
2882 "minicom" terminal emulation program for serial download. I (wd)
2883 consider minicom to be broken, and recommend not to use it. Under
2884 Unix, I recommend to use C-Kermit for general purpose use (and
2885 especially for kermit binary protocol download ("loadb" command), and
2886 use "cu" for S-Record download ("loads" command).
2888 Nevertheless, if you absolutely want to use it try adding this
2889 configuration to your "File transfer protocols" section:
2891 Name Program Name U/D FullScr IO-Red. Multi
2892 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
2893 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
2899 Starting at version 0.9.2, U-Boot supports NetBSD both as host
2900 (build U-Boot) and target system (boots NetBSD/mpc8xx).
2902 Building requires a cross environment; it is known to work on
2903 NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
2904 need gmake since the Makefiles are not compatible with BSD make).
2905 Note that the cross-powerpc package does not install include files;
2906 attempting to build U-Boot will fail because <machine/ansi.h> is
2907 missing. This file has to be installed and patched manually:
2909 # cd /usr/pkg/cross/powerpc-netbsd/include
2911 # ln -s powerpc machine
2912 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
2913 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
2915 Native builds *don't* work due to incompatibilities between native
2916 and U-Boot include files.
2918 Booting assumes that (the first part of) the image booted is a
2919 stage-2 loader which in turn loads and then invokes the kernel
2920 proper. Loader sources will eventually appear in the NetBSD source
2921 tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
2922 meantime, send mail to bruno@exet-ag.de and/or wd@denx.de for
2926 Implementation Internals:
2927 =========================
2929 The following is not intended to be a complete description of every
2930 implementation detail. However, it should help to understand the
2931 inner workings of U-Boot and make it easier to port it to custom
2935 Initial Stack, Global Data:
2936 ---------------------------
2938 The implementation of U-Boot is complicated by the fact that U-Boot
2939 starts running out of ROM (flash memory), usually without access to
2940 system RAM (because the memory controller is not initialized yet).
2941 This means that we don't have writable Data or BSS segments, and BSS
2942 is not initialized as zero. To be able to get a C environment working
2943 at all, we have to allocate at least a minimal stack. Implementation
2944 options for this are defined and restricted by the CPU used: Some CPU
2945 models provide on-chip memory (like the IMMR area on MPC8xx and
2946 MPC826x processors), on others (parts of) the data cache can be
2947 locked as (mis-) used as memory, etc.
2949 Chris Hallinan posted a good summary of these issues to the
2950 u-boot-users mailing list:
2952 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
2953 From: "Chris Hallinan" <clh@net1plus.com>
2954 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
2957 Correct me if I'm wrong, folks, but the way I understand it
2958 is this: Using DCACHE as initial RAM for Stack, etc, does not
2959 require any physical RAM backing up the cache. The cleverness
2960 is that the cache is being used as a temporary supply of
2961 necessary storage before the SDRAM controller is setup. It's
2962 beyond the scope of this list to expain the details, but you
2963 can see how this works by studying the cache architecture and
2964 operation in the architecture and processor-specific manuals.
2966 OCM is On Chip Memory, which I believe the 405GP has 4K. It
2967 is another option for the system designer to use as an
2968 initial stack/ram area prior to SDRAM being available. Either
2969 option should work for you. Using CS 4 should be fine if your
2970 board designers haven't used it for something that would
2971 cause you grief during the initial boot! It is frequently not
2974 CFG_INIT_RAM_ADDR should be somewhere that won't interfere
2975 with your processor/board/system design. The default value
2976 you will find in any recent u-boot distribution in
2977 Walnut405.h should work for you. I'd set it to a value larger
2978 than your SDRAM module. If you have a 64MB SDRAM module, set
2979 it above 400_0000. Just make sure your board has no resources
2980 that are supposed to respond to that address! That code in
2981 start.S has been around a while and should work as is when
2982 you get the config right.
2987 It is essential to remember this, since it has some impact on the C
2988 code for the initialization procedures:
2990 * Initialized global data (data segment) is read-only. Do not attempt
2993 * Do not use any unitialized global data (or implicitely initialized
2994 as zero data - BSS segment) at all - this is undefined, initiali-
2995 zation is performed later (when relocating to RAM).
2997 * Stack space is very limited. Avoid big data buffers or things like
3000 Having only the stack as writable memory limits means we cannot use
3001 normal global data to share information beween the code. But it
3002 turned out that the implementation of U-Boot can be greatly
3003 simplified by making a global data structure (gd_t) available to all
3004 functions. We could pass a pointer to this data as argument to _all_
3005 functions, but this would bloat the code. Instead we use a feature of
3006 the GCC compiler (Global Register Variables) to share the data: we
3007 place a pointer (gd) to the global data into a register which we
3008 reserve for this purpose.
3010 When choosing a register for such a purpose we are restricted by the
3011 relevant (E)ABI specifications for the current architecture, and by
3012 GCC's implementation.
3014 For PowerPC, the following registers have specific use:
3017 R3-R4: parameter passing and return values
3018 R5-R10: parameter passing
3019 R13: small data area pointer
3023 (U-Boot also uses R14 as internal GOT pointer.)
3025 ==> U-Boot will use R29 to hold a pointer to the global data
3027 Note: on PPC, we could use a static initializer (since the
3028 address of the global data structure is known at compile time),
3029 but it turned out that reserving a register results in somewhat
3030 smaller code - although the code savings are not that big (on
3031 average for all boards 752 bytes for the whole U-Boot image,
3032 624 text + 127 data).
3034 On ARM, the following registers are used:
3036 R0: function argument word/integer result
3037 R1-R3: function argument word
3039 R10: stack limit (used only if stack checking if enabled)
3040 R11: argument (frame) pointer
3041 R12: temporary workspace
3044 R15: program counter
3046 ==> U-Boot will use R8 to hold a pointer to the global data
3052 U-Boot runs in system state and uses physical addresses, i.e. the
3053 MMU is not used either for address mapping nor for memory protection.
3055 The available memory is mapped to fixed addresses using the memory
3056 controller. In this process, a contiguous block is formed for each
3057 memory type (Flash, SDRAM, SRAM), even when it consists of several
3058 physical memory banks.
3060 U-Boot is installed in the first 128 kB of the first Flash bank (on
3061 TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
3062 booting and sizing and initializing DRAM, the code relocates itself
3063 to the upper end of DRAM. Immediately below the U-Boot code some
3064 memory is reserved for use by malloc() [see CFG_MALLOC_LEN
3065 configuration setting]. Below that, a structure with global Board
3066 Info data is placed, followed by the stack (growing downward).
3068 Additionally, some exception handler code is copied to the low 8 kB
3069 of DRAM (0x00000000 ... 0x00001FFF).
3071 So a typical memory configuration with 16 MB of DRAM could look like
3074 0x0000 0000 Exception Vector code
3077 0x0000 2000 Free for Application Use
3083 0x00FB FF20 Monitor Stack (Growing downward)
3084 0x00FB FFAC Board Info Data and permanent copy of global data
3085 0x00FC 0000 Malloc Arena
3088 0x00FE 0000 RAM Copy of Monitor Code
3089 ... eventually: LCD or video framebuffer
3090 ... eventually: pRAM (Protected RAM - unchanged by reset)
3091 0x00FF FFFF [End of RAM]
3094 System Initialization:
3095 ----------------------
3097 In the reset configuration, U-Boot starts at the reset entry point
3098 (on most PowerPC systens at address 0x00000100). Because of the reset
3099 configuration for CS0# this is a mirror of the onboard Flash memory.
3100 To be able to re-map memory U-Boot then jumps to its link address.
3101 To be able to implement the initialization code in C, a (small!)
3102 initial stack is set up in the internal Dual Ported RAM (in case CPUs
3103 which provide such a feature like MPC8xx or MPC8260), or in a locked
3104 part of the data cache. After that, U-Boot initializes the CPU core,
3105 the caches and the SIU.
3107 Next, all (potentially) available memory banks are mapped using a
3108 preliminary mapping. For example, we put them on 512 MB boundaries
3109 (multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
3110 on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
3111 programmed for SDRAM access. Using the temporary configuration, a
3112 simple memory test is run that determines the size of the SDRAM
3115 When there is more than one SDRAM bank, and the banks are of
3116 different size, the largest is mapped first. For equal size, the first
3117 bank (CS2#) is mapped first. The first mapping is always for address
3118 0x00000000, with any additional banks following immediately to create
3119 contiguous memory starting from 0.
3121 Then, the monitor installs itself at the upper end of the SDRAM area
3122 and allocates memory for use by malloc() and for the global Board
3123 Info data; also, the exception vector code is copied to the low RAM
3124 pages, and the final stack is set up.
3126 Only after this relocation will you have a "normal" C environment;
3127 until that you are restricted in several ways, mostly because you are
3128 running from ROM, and because the code will have to be relocated to a
3132 U-Boot Porting Guide:
3133 ----------------------
3135 [Based on messages by Jerry Van Baren in the U-Boot-Users mailing
3139 int main (int argc, char *argv[])
3141 sighandler_t no_more_time;
3143 signal (SIGALRM, no_more_time);
3144 alarm (PROJECT_DEADLINE - toSec (3 * WEEK));
3146 if (available_money > available_manpower) {
3147 pay consultant to port U-Boot;
3151 Download latest U-Boot source;
3153 Subscribe to u-boot-users mailing list;
3156 email ("Hi, I am new to U-Boot, how do I get started?");
3160 Read the README file in the top level directory;
3161 Read http://www.denx.de/twiki/bin/view/DULG/Manual ;
3162 Read the source, Luke;
3165 if (available_money > toLocalCurrency ($2500)) {
3168 Add a lot of aggravation and time;
3171 Create your own board support subdirectory;
3173 Create your own board config file;
3177 Add / modify source code;
3181 email ("Hi, I am having problems...");
3183 Send patch file to Wolfgang;
3188 void no_more_time (int sig)
3197 All contributions to U-Boot should conform to the Linux kernel
3198 coding style; see the file "Documentation/CodingStyle" in your Linux
3199 kernel source directory.
3201 Please note that U-Boot is implemented in C (and to some small parts
3202 in Assembler); no C++ is used, so please do not use C++ style
3203 comments (//) in your code.
3205 Please also stick to the following formatting rules:
3206 - remove any trailing white space
3207 - use TAB characters for indentation, not spaces
3208 - make sure NOT to use DOS '\r\n' line feeds
3209 - do not add more than 2 empty lines to source files
3210 - do not add trailing empty lines to source files
3212 Submissions which do not conform to the standards may be returned
3213 with a request to reformat the changes.
3219 Since the number of patches for U-Boot is growing, we need to
3220 establish some rules. Submissions which do not conform to these rules
3221 may be rejected, even when they contain important and valuable stuff.
3224 When you send a patch, please include the following information with
3227 * For bug fixes: a description of the bug and how your patch fixes
3228 this bug. Please try to include a way of demonstrating that the
3229 patch actually fixes something.
3231 * For new features: a description of the feature and your
3234 * A CHANGELOG entry as plaintext (separate from the patch)
3236 * For major contributions, your entry to the CREDITS file
3238 * When you add support for a new board, don't forget to add this
3239 board to the MAKEALL script, too.
3241 * If your patch adds new configuration options, don't forget to
3242 document these in the README file.
3244 * The patch itself. If you are accessing the CVS repository use "cvs
3245 update; cvs diff -puRN"; else, use "diff -purN OLD NEW". If your
3246 version of diff does not support these options, then get the latest
3247 version of GNU diff.
3249 The current directory when running this command shall be the top
3250 level directory of the U-Boot source tree, or it's parent directory
3251 (i. e. please make sure that your patch includes sufficient
3252 directory information for the affected files).
3254 We accept patches as plain text, MIME attachments or as uuencoded
3257 * If one logical set of modifications affects or creates several
3258 files, all these changes shall be submitted in a SINGLE patch file.
3260 * Changesets that contain different, unrelated modifications shall be
3261 submitted as SEPARATE patches, one patch per changeset.
3266 * Before sending the patch, run the MAKEALL script on your patched
3267 source tree and make sure that no errors or warnings are reported
3268 for any of the boards.
3270 * Keep your modifications to the necessary minimum: A patch
3271 containing several unrelated changes or arbitrary reformats will be
3272 returned with a request to re-formatting / split it.
3274 * If you modify existing code, make sure that your new code does not
3275 add to the memory footprint of the code ;-) Small is beautiful!
3276 When adding new features, these should compile conditionally only
3277 (using #ifdef), and the resulting code with the new feature
3278 disabled must not need more memory than the old code without your
projects / platform / kernel / u-boot.git / blob