1# 2# (C) Copyright 2000 - 2008 3# Wolfgang Denk, DENX Software Engineering, wd@denx.de. 4# 5# See file CREDITS for list of people who contributed to this 6# project. 7# 8# This program is free software; you can redistribute it and/or 9# modify it under the terms of the GNU General Public License as 10# published by the Free Software Foundation; either version 2 of 11# the License, or (at your option) any later version. 12# 13# This program is distributed in the hope that it will be useful, 14# but WITHOUT ANY WARRANTY; without even the implied warranty of 15# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16# GNU General Public License for more details. 17# 18# You should have received a copy of the GNU General Public License 19# along with this program; if not, write to the Free Software 20# Foundation, Inc., 59 Temple Place, Suite 330, Boston, 21# MA 02111-1307 USA 22# 23 24Summary: 25======== 26 27This directory contains the source code for U-Boot, a boot loader for 28Embedded boards based on PowerPC, ARM, MIPS and several other 29processors, which can be installed in a boot ROM and used to 30initialize and test the hardware or to download and run application 31code. 32 33The development of U-Boot is closely related to Linux: some parts of 34the source code originate in the Linux source tree, we have some 35header files in common, and special provision has been made to 36support booting of Linux images. 37 38Some attention has been paid to make this software easily 39configurable and extendable. For instance, all monitor commands are 40implemented with the same call interface, so that it's very easy to 41add new commands. Also, instead of permanently adding rarely used 42code (for instance hardware test utilities) to the monitor, you can 43load and run it dynamically. 44 45 46Status: 47======= 48 49In general, all boards for which a configuration option exists in the 50Makefile have been tested to some extent and can be considered 51"working". In fact, many of them are used in production systems. 52 53In case of problems see the CHANGELOG and CREDITS files to find out 54who contributed the specific port. The MAINTAINERS file lists board 55maintainers. 56 57 58Where to get help: 59================== 60 61In case you have questions about, problems with or contributions for 62U-Boot you should send a message to the U-Boot mailing list at 63<u-boot-users@lists.sourceforge.net>. There is also an archive of 64previous traffic on the mailing list - please search the archive 65before asking FAQ's. Please see 66http://lists.sourceforge.net/lists/listinfo/u-boot-users/ 67 68 69Where to get source code: 70========================= 71 72The U-Boot source code is maintained in the git repository at 73git://www.denx.de/git/u-boot.git ; you can browse it online at 74http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary 75 76The "snapshot" links on this page allow you to download tarballs of 77any version you might be interested in. Ofifcial releases are also 78available for FTP download from the ftp://ftp.denx.de/pub/u-boot/ 79directory. 80 81Pre-build (and tested) images are available from 82ftp://ftp.denx.de/pub/u-boot/images/ 83 84 85Where we come from: 86=================== 87 88- start from 8xxrom sources 89- create PPCBoot project (http://sourceforge.net/projects/ppcboot) 90- clean up code 91- make it easier to add custom boards 92- make it possible to add other [PowerPC] CPUs 93- extend functions, especially: 94 * Provide extended interface to Linux boot loader 95 * S-Record download 96 * network boot 97 * PCMCIA / CompactFLash / ATA disk / SCSI ... boot 98- create ARMBoot project (http://sourceforge.net/projects/armboot) 99- add other CPU families (starting with ARM) 100- create U-Boot project (http://sourceforge.net/projects/u-boot) 101- current project page: see http://www.denx.de/wiki/UBoot 102 103 104Names and Spelling: 105=================== 106 107The "official" name of this project is "Das U-Boot". The spelling 108"U-Boot" shall be used in all written text (documentation, comments 109in source files etc.). Example: 110 111 This is the README file for the U-Boot project. 112 113File names etc. shall be based on the string "u-boot". Examples: 114 115 include/asm-ppc/u-boot.h 116 117 #include <asm/u-boot.h> 118 119Variable names, preprocessor constants etc. shall be either based on 120the string "u_boot" or on "U_BOOT". Example: 121 122 U_BOOT_VERSION u_boot_logo 123 IH_OS_U_BOOT u_boot_hush_start 124 125 126Versioning: 127=========== 128 129U-Boot uses a 3 level version number containing a version, a 130sub-version, and a patchlevel: "U-Boot-2.34.5" means version "2", 131sub-version "34", and patchlevel "4". 132 133The patchlevel is used to indicate certain stages of development 134between released versions, i. e. officially released versions of 135U-Boot will always have a patchlevel of "0". 136 137 138Directory Hierarchy: 139==================== 140 141- board Board dependent files 142- common Misc architecture independent functions 143- cpu CPU specific files 144 - 74xx_7xx Files specific to Freescale MPC74xx and 7xx CPUs 145 - arm720t Files specific to ARM 720 CPUs 146 - arm920t Files specific to ARM 920 CPUs 147 - at91rm9200 Files specific to Atmel AT91RM9200 CPU 148 - imx Files specific to Freescale MC9328 i.MX CPUs 149 - s3c24x0 Files specific to Samsung S3C24X0 CPUs 150 - arm925t Files specific to ARM 925 CPUs 151 - arm926ejs Files specific to ARM 926 CPUs 152 - arm1136 Files specific to ARM 1136 CPUs 153 - at32ap Files specific to Atmel AVR32 AP CPUs 154 - i386 Files specific to i386 CPUs 155 - ixp Files specific to Intel XScale IXP CPUs 156 - mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs 157 - mcf5227x Files specific to Freescale ColdFire MCF5227x CPUs 158 - mcf532x Files specific to Freescale ColdFire MCF5329 CPUs 159 - mcf5445x Files specific to Freescale ColdFire MCF5445x CPUs 160 - mcf547x_8x Files specific to Freescale ColdFire MCF547x_8x CPUs 161 - mips Files specific to MIPS CPUs 162 - mpc5xx Files specific to Freescale MPC5xx CPUs 163 - mpc5xxx Files specific to Freescale MPC5xxx CPUs 164 - mpc8xx Files specific to Freescale MPC8xx CPUs 165 - mpc8220 Files specific to Freescale MPC8220 CPUs 166 - mpc824x Files specific to Freescale MPC824x CPUs 167 - mpc8260 Files specific to Freescale MPC8260 CPUs 168 - mpc85xx Files specific to Freescale MPC85xx CPUs 169 - nios Files specific to Altera NIOS CPUs 170 - nios2 Files specific to Altera Nios-II CPUs 171 - ppc4xx Files specific to AMCC PowerPC 4xx CPUs 172 - pxa Files specific to Intel XScale PXA CPUs 173 - s3c44b0 Files specific to Samsung S3C44B0 CPUs 174 - sa1100 Files specific to Intel StrongARM SA1100 CPUs 175- disk Code for disk drive partition handling 176- doc Documentation (don't expect too much) 177- drivers Commonly used device drivers 178- dtt Digital Thermometer and Thermostat drivers 179- examples Example code for standalone applications, etc. 180- include Header Files 181- lib_arm Files generic to ARM architecture 182- lib_avr32 Files generic to AVR32 architecture 183- lib_generic Files generic to all architectures 184- lib_i386 Files generic to i386 architecture 185- lib_m68k Files generic to m68k architecture 186- lib_mips Files generic to MIPS architecture 187- lib_nios Files generic to NIOS architecture 188- lib_ppc Files generic to PowerPC architecture 189- libfdt Library files to support flattened device trees 190- net Networking code 191- post Power On Self Test 192- rtc Real Time Clock drivers 193- tools Tools to build S-Record or U-Boot images, etc. 194 195Software Configuration: 196======================= 197 198Configuration is usually done using C preprocessor defines; the 199rationale behind that is to avoid dead code whenever possible. 200 201There are two classes of configuration variables: 202 203* Configuration _OPTIONS_: 204 These are selectable by the user and have names beginning with 205 "CONFIG_". 206 207* Configuration _SETTINGS_: 208 These depend on the hardware etc. and should not be meddled with if 209 you don't know what you're doing; they have names beginning with 210 "CFG_". 211 212Later we will add a configuration tool - probably similar to or even 213identical to what's used for the Linux kernel. Right now, we have to 214do the configuration by hand, which means creating some symbolic 215links and editing some configuration files. We use the TQM8xxL boards 216as an example here. 217 218 219Selection of Processor Architecture and Board Type: 220--------------------------------------------------- 221 222For all supported boards there are ready-to-use default 223configurations available; just type "make <board_name>_config". 224 225Example: For a TQM823L module type: 226 227 cd u-boot 228 make TQM823L_config 229 230For the Cogent platform, you need to specify the cpu type as well; 231e.g. "make cogent_mpc8xx_config". And also configure the cogent 232directory according to the instructions in cogent/README. 233 234 235Configuration Options: 236---------------------- 237 238Configuration depends on the combination of board and CPU type; all 239such information is kept in a configuration file 240"include/configs/<board_name>.h". 241 242Example: For a TQM823L module, all configuration settings are in 243"include/configs/TQM823L.h". 244 245 246Many of the options are named exactly as the corresponding Linux 247kernel configuration options. The intention is to make it easier to 248build a config tool - later. 249 250 251The following options need to be configured: 252 253- CPU Type: Define exactly one, e.g. CONFIG_MPC85XX. 254 255- Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS. 256 257- CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined) 258 Define exactly one, e.g. CONFIG_ATSTK1002 259 260- CPU Module Type: (if CONFIG_COGENT is defined) 261 Define exactly one of 262 CONFIG_CMA286_60_OLD 263--- FIXME --- not tested yet: 264 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P, 265 CONFIG_CMA287_23, CONFIG_CMA287_50 266 267- Motherboard Type: (if CONFIG_COGENT is defined) 268 Define exactly one of 269 CONFIG_CMA101, CONFIG_CMA102 270 271- Motherboard I/O Modules: (if CONFIG_COGENT is defined) 272 Define one or more of 273 CONFIG_CMA302 274 275- Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined) 276 Define one or more of 277 CONFIG_LCD_HEARTBEAT - update a character position on 278 the lcd display every second with 279 a "rotator" |\-/|\-/ 280 281- Board flavour: (if CONFIG_MPC8260ADS is defined) 282 CONFIG_ADSTYPE 283 Possible values are: 284 CFG_8260ADS - original MPC8260ADS 285 CFG_8266ADS - MPC8266ADS 286 CFG_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR 287 CFG_8272ADS - MPC8272ADS 288 289- MPC824X Family Member (if CONFIG_MPC824X is defined) 290 Define exactly one of 291 CONFIG_MPC8240, CONFIG_MPC8245 292 293- 8xx CPU Options: (if using an MPC8xx cpu) 294 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if 295 get_gclk_freq() cannot work 296 e.g. if there is no 32KHz 297 reference PIT/RTC clock 298 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK 299 or XTAL/EXTAL) 300 301- 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU): 302 CFG_8xx_CPUCLK_MIN 303 CFG_8xx_CPUCLK_MAX 304 CONFIG_8xx_CPUCLK_DEFAULT 305 See doc/README.MPC866 306 307 CFG_MEASURE_CPUCLK 308 309 Define this to measure the actual CPU clock instead 310 of relying on the correctness of the configured 311 values. Mostly useful for board bringup to make sure 312 the PLL is locked at the intended frequency. Note 313 that this requires a (stable) reference clock (32 kHz 314 RTC clock or CFG_8XX_XIN) 315 316- Intel Monahans options: 317 CFG_MONAHANS_RUN_MODE_OSC_RATIO 318 319 Defines the Monahans run mode to oscillator 320 ratio. Valid values are 8, 16, 24, 31. The core 321 frequency is this value multiplied by 13 MHz. 322 323 CFG_MONAHANS_TURBO_RUN_MODE_RATIO 324 325 Defines the Monahans turbo mode to oscillator 326 ratio. Valid values are 1 (default if undefined) and 327 2. The core frequency as calculated above is multiplied 328 by this value. 329 330- Linux Kernel Interface: 331 CONFIG_CLOCKS_IN_MHZ 332 333 U-Boot stores all clock information in Hz 334 internally. For binary compatibility with older Linux 335 kernels (which expect the clocks passed in the 336 bd_info data to be in MHz) the environment variable 337 "clocks_in_mhz" can be defined so that U-Boot 338 converts clock data to MHZ before passing it to the 339 Linux kernel. 340 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of 341 "clocks_in_mhz=1" is automatically included in the 342 default environment. 343 344 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only] 345 346 When transfering memsize parameter to linux, some versions 347 expect it to be in bytes, others in MB. 348 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes. 349 350 CONFIG_OF_LIBFDT / CONFIG_OF_FLAT_TREE 351 352 New kernel versions are expecting firmware settings to be 353 passed using flattened device trees (based on open firmware 354 concepts). 355 356 CONFIG_OF_LIBFDT 357 * New libfdt-based support 358 * Adds the "fdt" command 359 * The bootm command automatically updates the fdt 360 361 CONFIG_OF_FLAT_TREE 362 * Deprecated, see CONFIG_OF_LIBFDT 363 * Original ft_build.c-based support 364 * Automatically modifies the dft as part of the bootm command 365 * The environment variable "disable_of", when set, 366 disables this functionality. 367 368 OF_CPU - The proper name of the cpus node. 369 OF_SOC - The proper name of the soc node. 370 OF_TBCLK - The timebase frequency. 371 OF_STDOUT_PATH - The path to the console device 372 373 boards with QUICC Engines require OF_QE to set UCC mac addresses 374 375 CONFIG_OF_HAS_BD_T 376 377 * CONFIG_OF_LIBFDT - enables the "fdt bd_t" command 378 * CONFIG_OF_FLAT_TREE - The resulting flat device tree 379 will have a copy of the bd_t. Space should be 380 pre-allocated in the dts for the bd_t. 381 382 CONFIG_OF_HAS_UBOOT_ENV 383 384 * CONFIG_OF_LIBFDT - enables the "fdt env" command 385 * CONFIG_OF_FLAT_TREE - The resulting flat device tree 386 will have a copy of u-boot's environment variables 387 388 CONFIG_OF_BOARD_SETUP 389 390 Board code has addition modification that it wants to make 391 to the flat device tree before handing it off to the kernel 392 393 CONFIG_OF_BOOT_CPU 394 395 This define fills in the correct boot cpu in the boot 396 param header, the default value is zero if undefined. 397 398- Serial Ports: 399 CFG_PL010_SERIAL 400 401 Define this if you want support for Amba PrimeCell PL010 UARTs. 402 403 CFG_PL011_SERIAL 404 405 Define this if you want support for Amba PrimeCell PL011 UARTs. 406 407 CONFIG_PL011_CLOCK 408 409 If you have Amba PrimeCell PL011 UARTs, set this variable to 410 the clock speed of the UARTs. 411 412 CONFIG_PL01x_PORTS 413 414 If you have Amba PrimeCell PL010 or PL011 UARTs on your board, 415 define this to a list of base addresses for each (supported) 416 port. See e.g. include/configs/versatile.h 417 418 419- Console Interface: 420 Depending on board, define exactly one serial port 421 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2, 422 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial 423 console by defining CONFIG_8xx_CONS_NONE 424 425 Note: if CONFIG_8xx_CONS_NONE is defined, the serial 426 port routines must be defined elsewhere 427 (i.e. serial_init(), serial_getc(), ...) 428 429 CONFIG_CFB_CONSOLE 430 Enables console device for a color framebuffer. Needs following 431 defines (cf. smiLynxEM, i8042, board/eltec/bab7xx) 432 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation 433 (default big endian) 434 VIDEO_HW_RECTFILL graphic chip supports 435 rectangle fill 436 (cf. smiLynxEM) 437 VIDEO_HW_BITBLT graphic chip supports 438 bit-blit (cf. smiLynxEM) 439 VIDEO_VISIBLE_COLS visible pixel columns 440 (cols=pitch) 441 VIDEO_VISIBLE_ROWS visible pixel rows 442 VIDEO_PIXEL_SIZE bytes per pixel 443 VIDEO_DATA_FORMAT graphic data format 444 (0-5, cf. cfb_console.c) 445 VIDEO_FB_ADRS framebuffer address 446 VIDEO_KBD_INIT_FCT keyboard int fct 447 (i.e. i8042_kbd_init()) 448 VIDEO_TSTC_FCT test char fct 449 (i.e. i8042_tstc) 450 VIDEO_GETC_FCT get char fct 451 (i.e. i8042_getc) 452 CONFIG_CONSOLE_CURSOR cursor drawing on/off 453 (requires blink timer 454 cf. i8042.c) 455 CFG_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c) 456 CONFIG_CONSOLE_TIME display time/date info in 457 upper right corner 458 (requires CONFIG_CMD_DATE) 459 CONFIG_VIDEO_LOGO display Linux logo in 460 upper left corner 461 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of 462 linux_logo.h for logo. 463 Requires CONFIG_VIDEO_LOGO 464 CONFIG_CONSOLE_EXTRA_INFO 465 addional board info beside 466 the logo 467 468 When CONFIG_CFB_CONSOLE is defined, video console is 469 default i/o. Serial console can be forced with 470 environment 'console=serial'. 471 472 When CONFIG_SILENT_CONSOLE is defined, all console 473 messages (by U-Boot and Linux!) can be silenced with 474 the "silent" environment variable. See 475 doc/README.silent for more information. 476 477- Console Baudrate: 478 CONFIG_BAUDRATE - in bps 479 Select one of the baudrates listed in 480 CFG_BAUDRATE_TABLE, see below. 481 CFG_BRGCLK_PRESCALE, baudrate prescale 482 483- Interrupt driven serial port input: 484 CONFIG_SERIAL_SOFTWARE_FIFO 485 486 PPC405GP only. 487 Use an interrupt handler for receiving data on the 488 serial port. It also enables using hardware handshake 489 (RTS/CTS) and UART's built-in FIFO. Set the number of 490 bytes the interrupt driven input buffer should have. 491 492 Leave undefined to disable this feature, including 493 disable the buffer and hardware handshake. 494 495- Console UART Number: 496 CONFIG_UART1_CONSOLE 497 498 AMCC PPC4xx only. 499 If defined internal UART1 (and not UART0) is used 500 as default U-Boot console. 501 502- Boot Delay: CONFIG_BOOTDELAY - in seconds 503 Delay before automatically booting the default image; 504 set to -1 to disable autoboot. 505 506 See doc/README.autoboot for these options that 507 work with CONFIG_BOOTDELAY. None are required. 508 CONFIG_BOOT_RETRY_TIME 509 CONFIG_BOOT_RETRY_MIN 510 CONFIG_AUTOBOOT_KEYED 511 CONFIG_AUTOBOOT_PROMPT 512 CONFIG_AUTOBOOT_DELAY_STR 513 CONFIG_AUTOBOOT_STOP_STR 514 CONFIG_AUTOBOOT_DELAY_STR2 515 CONFIG_AUTOBOOT_STOP_STR2 516 CONFIG_ZERO_BOOTDELAY_CHECK 517 CONFIG_RESET_TO_RETRY 518 519- Autoboot Command: 520 CONFIG_BOOTCOMMAND 521 Only needed when CONFIG_BOOTDELAY is enabled; 522 define a command string that is automatically executed 523 when no character is read on the console interface 524 within "Boot Delay" after reset. 525 526 CONFIG_BOOTARGS 527 This can be used to pass arguments to the bootm 528 command. The value of CONFIG_BOOTARGS goes into the 529 environment value "bootargs". 530 531 CONFIG_RAMBOOT and CONFIG_NFSBOOT 532 The value of these goes into the environment as 533 "ramboot" and "nfsboot" respectively, and can be used 534 as a convenience, when switching between booting from 535 ram and nfs. 536 537- Pre-Boot Commands: 538 CONFIG_PREBOOT 539 540 When this option is #defined, the existence of the 541 environment variable "preboot" will be checked 542 immediately before starting the CONFIG_BOOTDELAY 543 countdown and/or running the auto-boot command resp. 544 entering interactive mode. 545 546 This feature is especially useful when "preboot" is 547 automatically generated or modified. For an example 548 see the LWMON board specific code: here "preboot" is 549 modified when the user holds down a certain 550 combination of keys on the (special) keyboard when 551 booting the systems 552 553- Serial Download Echo Mode: 554 CONFIG_LOADS_ECHO 555 If defined to 1, all characters received during a 556 serial download (using the "loads" command) are 557 echoed back. This might be needed by some terminal 558 emulations (like "cu"), but may as well just take 559 time on others. This setting #define's the initial 560 value of the "loads_echo" environment variable. 561 562- Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined) 563 CONFIG_KGDB_BAUDRATE 564 Select one of the baudrates listed in 565 CFG_BAUDRATE_TABLE, see below. 566 567- Monitor Functions: 568 Monitor commands can be included or excluded 569 from the build by using the #include files 570 "config_cmd_all.h" and #undef'ing unwanted 571 commands, or using "config_cmd_default.h" 572 and augmenting with additional #define's 573 for wanted commands. 574 575 The default command configuration includes all commands 576 except those marked below with a "*". 577 578 CONFIG_CMD_ASKENV * ask for env variable 579 CONFIG_CMD_AUTOSCRIPT Autoscript Support 580 CONFIG_CMD_BDI bdinfo 581 CONFIG_CMD_BEDBUG * Include BedBug Debugger 582 CONFIG_CMD_BMP * BMP support 583 CONFIG_CMD_BSP * Board specific commands 584 CONFIG_CMD_BOOTD bootd 585 CONFIG_CMD_CACHE * icache, dcache 586 CONFIG_CMD_CONSOLE coninfo 587 CONFIG_CMD_DATE * support for RTC, date/time... 588 CONFIG_CMD_DHCP * DHCP support 589 CONFIG_CMD_DIAG * Diagnostics 590 CONFIG_CMD_DOC * Disk-On-Chip Support 591 CONFIG_CMD_DTT * Digital Therm and Thermostat 592 CONFIG_CMD_ECHO echo arguments 593 CONFIG_CMD_EEPROM * EEPROM read/write support 594 CONFIG_CMD_ELF * bootelf, bootvx 595 CONFIG_CMD_ENV saveenv 596 CONFIG_CMD_FDC * Floppy Disk Support 597 CONFIG_CMD_FAT * FAT partition support 598 CONFIG_CMD_FDOS * Dos diskette Support 599 CONFIG_CMD_FLASH flinfo, erase, protect 600 CONFIG_CMD_FPGA FPGA device initialization support 601 CONFIG_CMD_HWFLOW * RTS/CTS hw flow control 602 CONFIG_CMD_I2C * I2C serial bus support 603 CONFIG_CMD_IDE * IDE harddisk support 604 CONFIG_CMD_IMI iminfo 605 CONFIG_CMD_IMLS List all found images 606 CONFIG_CMD_IMMAP * IMMR dump support 607 CONFIG_CMD_IRQ * irqinfo 608 CONFIG_CMD_ITEST Integer/string test of 2 values 609 CONFIG_CMD_JFFS2 * JFFS2 Support 610 CONFIG_CMD_KGDB * kgdb 611 CONFIG_CMD_LOADB loadb 612 CONFIG_CMD_LOADS loads 613 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base, 614 loop, loopw, mtest 615 CONFIG_CMD_MISC Misc functions like sleep etc 616 CONFIG_CMD_MMC * MMC memory mapped support 617 CONFIG_CMD_MII * MII utility commands 618 CONFIG_CMD_NAND * NAND support 619 CONFIG_CMD_NET bootp, tftpboot, rarpboot 620 CONFIG_CMD_PCI * pciinfo 621 CONFIG_CMD_PCMCIA * PCMCIA support 622 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network 623 host 624 CONFIG_CMD_PORTIO * Port I/O 625 CONFIG_CMD_REGINFO * Register dump 626 CONFIG_CMD_RUN run command in env variable 627 CONFIG_CMD_SAVES * save S record dump 628 CONFIG_CMD_SCSI * SCSI Support 629 CONFIG_CMD_SDRAM * print SDRAM configuration information 630 (requires CONFIG_CMD_I2C) 631 CONFIG_CMD_SETGETDCR Support for DCR Register access 632 (4xx only) 633 CONFIG_CMD_SPI * SPI serial bus support 634 CONFIG_CMD_USB * USB support 635 CONFIG_CMD_VFD * VFD support (TRAB) 636 CONFIG_CMD_BSP * Board SPecific functions 637 CONFIG_CMD_CDP * Cisco Discover Protocol support 638 CONFIG_CMD_FSL * Microblaze FSL support 639 640 641 EXAMPLE: If you want all functions except of network 642 support you can write: 643 644 #include "config_cmd_all.h" 645 #undef CONFIG_CMD_NET 646 647 Other Commands: 648 fdt (flattened device tree) command: CONFIG_OF_LIBFDT 649 650 Note: Don't enable the "icache" and "dcache" commands 651 (configuration option CONFIG_CMD_CACHE) unless you know 652 what you (and your U-Boot users) are doing. Data 653 cache cannot be enabled on systems like the 8xx or 654 8260 (where accesses to the IMMR region must be 655 uncached), and it cannot be disabled on all other 656 systems where we (mis-) use the data cache to hold an 657 initial stack and some data. 658 659 660 XXX - this list needs to get updated! 661 662- Watchdog: 663 CONFIG_WATCHDOG 664 If this variable is defined, it enables watchdog 665 support. There must be support in the platform specific 666 code for a watchdog. For the 8xx and 8260 CPUs, the 667 SIU Watchdog feature is enabled in the SYPCR 668 register. 669 670- U-Boot Version: 671 CONFIG_VERSION_VARIABLE 672 If this variable is defined, an environment variable 673 named "ver" is created by U-Boot showing the U-Boot 674 version as printed by the "version" command. 675 This variable is readonly. 676 677- Real-Time Clock: 678 679 When CONFIG_CMD_DATE is selected, the type of the RTC 680 has to be selected, too. Define exactly one of the 681 following options: 682 683 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx 684 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC 685 CONFIG_RTC_MC146818 - use MC146818 RTC 686 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC 687 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC 688 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC 689 CONFIG_RTC_DS164x - use Dallas DS164x RTC 690 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC 691 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC 692 693 Note that if the RTC uses I2C, then the I2C interface 694 must also be configured. See I2C Support, below. 695 696- Timestamp Support: 697 698 When CONFIG_TIMESTAMP is selected, the timestamp 699 (date and time) of an image is printed by image 700 commands like bootm or iminfo. This option is 701 automatically enabled when you select CONFIG_CMD_DATE . 702 703- Partition Support: 704 CONFIG_MAC_PARTITION and/or CONFIG_DOS_PARTITION 705 and/or CONFIG_ISO_PARTITION 706 707 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or 708 CONFIG_CMD_SCSI) you must configure support for at 709 least one partition type as well. 710 711- IDE Reset method: 712 CONFIG_IDE_RESET_ROUTINE - this is defined in several 713 board configurations files but used nowhere! 714 715 CONFIG_IDE_RESET - is this is defined, IDE Reset will 716 be performed by calling the function 717 ide_set_reset(int reset) 718 which has to be defined in a board specific file 719 720- ATAPI Support: 721 CONFIG_ATAPI 722 723 Set this to enable ATAPI support. 724 725- LBA48 Support 726 CONFIG_LBA48 727 728 Set this to enable support for disks larger than 137GB 729 Also look at CFG_64BIT_LBA ,CFG_64BIT_VSPRINTF and CFG_64BIT_STRTOUL 730 Whithout these , LBA48 support uses 32bit variables and will 'only' 731 support disks up to 2.1TB. 732 733 CFG_64BIT_LBA: 734 When enabled, makes the IDE subsystem use 64bit sector addresses. 735 Default is 32bit. 736 737- SCSI Support: 738 At the moment only there is only support for the 739 SYM53C8XX SCSI controller; define 740 CONFIG_SCSI_SYM53C8XX to enable it. 741 742 CFG_SCSI_MAX_LUN [8], CFG_SCSI_MAX_SCSI_ID [7] and 743 CFG_SCSI_MAX_DEVICE [CFG_SCSI_MAX_SCSI_ID * 744 CFG_SCSI_MAX_LUN] can be adjusted to define the 745 maximum numbers of LUNs, SCSI ID's and target 746 devices. 747 CFG_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz) 748 749- NETWORK Support (PCI): 750 CONFIG_E1000 751 Support for Intel 8254x gigabit chips. 752 753 CONFIG_EEPRO100 754 Support for Intel 82557/82559/82559ER chips. 755 Optional CONFIG_EEPRO100_SROM_WRITE enables eeprom 756 write routine for first time initialisation. 757 758 CONFIG_TULIP 759 Support for Digital 2114x chips. 760 Optional CONFIG_TULIP_SELECT_MEDIA for board specific 761 modem chip initialisation (KS8761/QS6611). 762 763 CONFIG_NATSEMI 764 Support for National dp83815 chips. 765 766 CONFIG_NS8382X 767 Support for National dp8382[01] gigabit chips. 768 769- NETWORK Support (other): 770 771 CONFIG_DRIVER_LAN91C96 772 Support for SMSC's LAN91C96 chips. 773 774 CONFIG_LAN91C96_BASE 775 Define this to hold the physical address 776 of the LAN91C96's I/O space 777 778 CONFIG_LAN91C96_USE_32_BIT 779 Define this to enable 32 bit addressing 780 781 CONFIG_DRIVER_SMC91111 782 Support for SMSC's LAN91C111 chip 783 784 CONFIG_SMC91111_BASE 785 Define this to hold the physical address 786 of the device (I/O space) 787 788 CONFIG_SMC_USE_32_BIT 789 Define this if data bus is 32 bits 790 791 CONFIG_SMC_USE_IOFUNCS 792 Define this to use i/o functions instead of macros 793 (some hardware wont work with macros) 794 795- USB Support: 796 At the moment only the UHCI host controller is 797 supported (PIP405, MIP405, MPC5200); define 798 CONFIG_USB_UHCI to enable it. 799 define CONFIG_USB_KEYBOARD to enable the USB Keyboard 800 and define CONFIG_USB_STORAGE to enable the USB 801 storage devices. 802 Note: 803 Supported are USB Keyboards and USB Floppy drives 804 (TEAC FD-05PUB). 805 MPC5200 USB requires additional defines: 806 CONFIG_USB_CLOCK 807 for 528 MHz Clock: 0x0001bbbb 808 CONFIG_USB_CONFIG 809 for differential drivers: 0x00001000 810 for single ended drivers: 0x00005000 811 CFG_USB_EVENT_POLL 812 May be defined to allow interrupt polling 813 instead of using asynchronous interrupts 814 815- USB Device: 816 Define the below if you wish to use the USB console. 817 Once firmware is rebuilt from a serial console issue the 818 command "setenv stdin usbtty; setenv stdout usbtty" and 819 attach your usb cable. The Unix command "dmesg" should print 820 it has found a new device. The environment variable usbtty 821 can be set to gserial or cdc_acm to enable your device to 822 appear to a USB host as a Linux gserial device or a 823 Common Device Class Abstract Control Model serial device. 824 If you select usbtty = gserial you should be able to enumerate 825 a Linux host by 826 # modprobe usbserial vendor=0xVendorID product=0xProductID 827 else if using cdc_acm, simply setting the environment 828 variable usbtty to be cdc_acm should suffice. The following 829 might be defined in YourBoardName.h 830 831 CONFIG_USB_DEVICE 832 Define this to build a UDC device 833 834 CONFIG_USB_TTY 835 Define this to have a tty type of device available to 836 talk to the UDC device 837 838 CFG_CONSOLE_IS_IN_ENV 839 Define this if you want stdin, stdout &/or stderr to 840 be set to usbtty. 841 842 mpc8xx: 843 CFG_USB_EXTC_CLK 0xBLAH 844 Derive USB clock from external clock "blah" 845 - CFG_USB_EXTC_CLK 0x02 846 847 CFG_USB_BRG_CLK 0xBLAH 848 Derive USB clock from brgclk 849 - CFG_USB_BRG_CLK 0x04 850 851 If you have a USB-IF assigned VendorID then you may wish to 852 define your own vendor specific values either in BoardName.h 853 or directly in usbd_vendor_info.h. If you don't define 854 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME, 855 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot 856 should pretend to be a Linux device to it's target host. 857 858 CONFIG_USBD_MANUFACTURER 859 Define this string as the name of your company for 860 - CONFIG_USBD_MANUFACTURER "my company" 861 862 CONFIG_USBD_PRODUCT_NAME 863 Define this string as the name of your product 864 - CONFIG_USBD_PRODUCT_NAME "acme usb device" 865 866 CONFIG_USBD_VENDORID 867 Define this as your assigned Vendor ID from the USB 868 Implementors Forum. This *must* be a genuine Vendor ID 869 to avoid polluting the USB namespace. 870 - CONFIG_USBD_VENDORID 0xFFFF 871 872 CONFIG_USBD_PRODUCTID 873 Define this as the unique Product ID 874 for your device 875 - CONFIG_USBD_PRODUCTID 0xFFFF 876 877 878- MMC Support: 879 The MMC controller on the Intel PXA is supported. To 880 enable this define CONFIG_MMC. The MMC can be 881 accessed from the boot prompt by mapping the device 882 to physical memory similar to flash. Command line is 883 enabled with CONFIG_CMD_MMC. The MMC driver also works with 884 the FAT fs. This is enabled with CONFIG_CMD_FAT. 885 886- Journaling Flash filesystem support: 887 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE, 888 CONFIG_JFFS2_NAND_DEV 889 Define these for a default partition on a NAND device 890 891 CFG_JFFS2_FIRST_SECTOR, 892 CFG_JFFS2_FIRST_BANK, CFG_JFFS2_NUM_BANKS 893 Define these for a default partition on a NOR device 894 895 CFG_JFFS_CUSTOM_PART 896 Define this to create an own partition. You have to provide a 897 function struct part_info* jffs2_part_info(int part_num) 898 899 If you define only one JFFS2 partition you may also want to 900 #define CFG_JFFS_SINGLE_PART 1 901 to disable the command chpart. This is the default when you 902 have not defined a custom partition 903 904- Keyboard Support: 905 CONFIG_ISA_KEYBOARD 906 907 Define this to enable standard (PC-Style) keyboard 908 support 909 910 CONFIG_I8042_KBD 911 Standard PC keyboard driver with US (is default) and 912 GERMAN key layout (switch via environment 'keymap=de') support. 913 Export function i8042_kbd_init, i8042_tstc and i8042_getc 914 for cfb_console. Supports cursor blinking. 915 916- Video support: 917 CONFIG_VIDEO 918 919 Define this to enable video support (for output to 920 video). 921 922 CONFIG_VIDEO_CT69000 923 924 Enable Chips & Technologies 69000 Video chip 925 926 CONFIG_VIDEO_SMI_LYNXEM 927 Enable Silicon Motion SMI 712/710/810 Video chip. The 928 video output is selected via environment 'videoout' 929 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is 930 assumed. 931 932 For the CT69000 and SMI_LYNXEM drivers, videomode is 933 selected via environment 'videomode'. Two diferent ways 934 are possible: 935 - "videomode=num" 'num' is a standard LiLo mode numbers. 936 Following standard modes are supported (* is default): 937 938 Colors 640x480 800x600 1024x768 1152x864 1280x1024 939 -------------+--------------------------------------------- 940 8 bits | 0x301* 0x303 0x305 0x161 0x307 941 15 bits | 0x310 0x313 0x316 0x162 0x319 942 16 bits | 0x311 0x314 0x317 0x163 0x31A 943 24 bits | 0x312 0x315 0x318 ? 0x31B 944 -------------+--------------------------------------------- 945 (i.e. setenv videomode 317; saveenv; reset;) 946 947 - "videomode=bootargs" all the video parameters are parsed 948 from the bootargs. (See drivers/video/videomodes.c) 949 950 951 CONFIG_VIDEO_SED13806 952 Enable Epson SED13806 driver. This driver supports 8bpp 953 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP 954 or CONFIG_VIDEO_SED13806_16BPP 955 956- Keyboard Support: 957 CONFIG_KEYBOARD 958 959 Define this to enable a custom keyboard support. 960 This simply calls drv_keyboard_init() which must be 961 defined in your board-specific files. 962 The only board using this so far is RBC823. 963 964- LCD Support: CONFIG_LCD 965 966 Define this to enable LCD support (for output to LCD 967 display); also select one of the supported displays 968 by defining one of these: 969 970 CONFIG_NEC_NL6448AC33: 971 972 NEC NL6448AC33-18. Active, color, single scan. 973 974 CONFIG_NEC_NL6448BC20 975 976 NEC NL6448BC20-08. 6.5", 640x480. 977 Active, color, single scan. 978 979 CONFIG_NEC_NL6448BC33_54 980 981 NEC NL6448BC33-54. 10.4", 640x480. 982 Active, color, single scan. 983 984 CONFIG_SHARP_16x9 985 986 Sharp 320x240. Active, color, single scan. 987 It isn't 16x9, and I am not sure what it is. 988 989 CONFIG_SHARP_LQ64D341 990 991 Sharp LQ64D341 display, 640x480. 992 Active, color, single scan. 993 994 CONFIG_HLD1045 995 996 HLD1045 display, 640x480. 997 Active, color, single scan. 998 999 CONFIG_OPTREX_BW 1000 1001 Optrex CBL50840-2 NF-FW 99 22 M5 1002 or 1003 Hitachi LMG6912RPFC-00T 1004 or 1005 Hitachi SP14Q002 1006 1007 320x240. Black & white. 1008 1009 Normally display is black on white background; define 1010 CFG_WHITE_ON_BLACK to get it inverted. 1011 1012- Splash Screen Support: CONFIG_SPLASH_SCREEN 1013 1014 If this option is set, the environment is checked for 1015 a variable "splashimage". If found, the usual display 1016 of logo, copyright and system information on the LCD 1017 is suppressed and the BMP image at the address 1018 specified in "splashimage" is loaded instead. The 1019 console is redirected to the "nulldev", too. This 1020 allows for a "silent" boot where a splash screen is 1021 loaded very quickly after power-on. 1022 1023- Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP 1024 1025 If this option is set, additionally to standard BMP 1026 images, gzipped BMP images can be displayed via the 1027 splashscreen support or the bmp command. 1028 1029- Compression support: 1030 CONFIG_BZIP2 1031 1032 If this option is set, support for bzip2 compressed 1033 images is included. If not, only uncompressed and gzip 1034 compressed images are supported. 1035 1036 NOTE: the bzip2 algorithm requires a lot of RAM, so 1037 the malloc area (as defined by CFG_MALLOC_LEN) should 1038 be at least 4MB. 1039 1040- MII/PHY support: 1041 CONFIG_PHY_ADDR 1042 1043 The address of PHY on MII bus. 1044 1045 CONFIG_PHY_CLOCK_FREQ (ppc4xx) 1046 1047 The clock frequency of the MII bus 1048 1049 CONFIG_PHY_GIGE 1050 1051 If this option is set, support for speed/duplex 1052 detection of Gigabit PHY is included. 1053 1054 CONFIG_PHY_RESET_DELAY 1055 1056 Some PHY like Intel LXT971A need extra delay after 1057 reset before any MII register access is possible. 1058 For such PHY, set this option to the usec delay 1059 required. (minimum 300usec for LXT971A) 1060 1061 CONFIG_PHY_CMD_DELAY (ppc4xx) 1062 1063 Some PHY like Intel LXT971A need extra delay after 1064 command issued before MII status register can be read 1065 1066- Ethernet address: 1067 CONFIG_ETHADDR 1068 CONFIG_ETH2ADDR 1069 CONFIG_ETH3ADDR 1070 1071 Define a default value for ethernet address to use 1072 for the respective ethernet interface, in case this 1073 is not determined automatically. 1074 1075- IP address: 1076 CONFIG_IPADDR 1077 1078 Define a default value for the IP address to use for 1079 the default ethernet interface, in case this is not 1080 determined through e.g. bootp. 1081 1082- Server IP address: 1083 CONFIG_SERVERIP 1084 1085 Defines a default value for theIP address of a TFTP 1086 server to contact when using the "tftboot" command. 1087 1088- Multicast TFTP Mode: 1089 CONFIG_MCAST_TFTP 1090 1091 Defines whether you want to support multicast TFTP as per 1092 rfc-2090; for example to work with atftp. Lets lots of targets 1093 tftp down the same boot image concurrently. Note: the ethernet 1094 driver in use must provide a function: mcast() to join/leave a 1095 multicast group. 1096 1097 CONFIG_BOOTP_RANDOM_DELAY 1098- BOOTP Recovery Mode: 1099 CONFIG_BOOTP_RANDOM_DELAY 1100 1101 If you have many targets in a network that try to 1102 boot using BOOTP, you may want to avoid that all 1103 systems send out BOOTP requests at precisely the same 1104 moment (which would happen for instance at recovery 1105 from a power failure, when all systems will try to 1106 boot, thus flooding the BOOTP server. Defining 1107 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be 1108 inserted before sending out BOOTP requests. The 1109 following delays are inserted then: 1110 1111 1st BOOTP request: delay 0 ... 1 sec 1112 2nd BOOTP request: delay 0 ... 2 sec 1113 3rd BOOTP request: delay 0 ... 4 sec 1114 4th and following 1115 BOOTP requests: delay 0 ... 8 sec 1116 1117- DHCP Advanced Options: 1118 You can fine tune the DHCP functionality by defining 1119 CONFIG_BOOTP_* symbols: 1120 1121 CONFIG_BOOTP_SUBNETMASK 1122 CONFIG_BOOTP_GATEWAY 1123 CONFIG_BOOTP_HOSTNAME 1124 CONFIG_BOOTP_NISDOMAIN 1125 CONFIG_BOOTP_BOOTPATH 1126 CONFIG_BOOTP_BOOTFILESIZE 1127 CONFIG_BOOTP_DNS 1128 CONFIG_BOOTP_DNS2 1129 CONFIG_BOOTP_SEND_HOSTNAME 1130 CONFIG_BOOTP_NTPSERVER 1131 CONFIG_BOOTP_TIMEOFFSET 1132 CONFIG_BOOTP_VENDOREX 1133 1134 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip 1135 environment variable, not the BOOTP server. 1136 1137 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS 1138 serverip from a DHCP server, it is possible that more 1139 than one DNS serverip is offered to the client. 1140 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS 1141 serverip will be stored in the additional environment 1142 variable "dnsip2". The first DNS serverip is always 1143 stored in the variable "dnsip", when CONFIG_BOOTP_DNS 1144 is defined. 1145 1146 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable 1147 to do a dynamic update of a DNS server. To do this, they 1148 need the hostname of the DHCP requester. 1149 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content 1150 of the "hostname" environment variable is passed as 1151 option 12 to the DHCP server. 1152 1153 - CDP Options: 1154 CONFIG_CDP_DEVICE_ID 1155 1156 The device id used in CDP trigger frames. 1157 1158 CONFIG_CDP_DEVICE_ID_PREFIX 1159 1160 A two character string which is prefixed to the MAC address 1161 of the device. 1162 1163 CONFIG_CDP_PORT_ID 1164 1165 A printf format string which contains the ascii name of 1166 the port. Normally is set to "eth%d" which sets 1167 eth0 for the first ethernet, eth1 for the second etc. 1168 1169 CONFIG_CDP_CAPABILITIES 1170 1171 A 32bit integer which indicates the device capabilities; 1172 0x00000010 for a normal host which does not forwards. 1173 1174 CONFIG_CDP_VERSION 1175 1176 An ascii string containing the version of the software. 1177 1178 CONFIG_CDP_PLATFORM 1179 1180 An ascii string containing the name of the platform. 1181 1182 CONFIG_CDP_TRIGGER 1183 1184 A 32bit integer sent on the trigger. 1185 1186 CONFIG_CDP_POWER_CONSUMPTION 1187 1188 A 16bit integer containing the power consumption of the 1189 device in .1 of milliwatts. 1190 1191 CONFIG_CDP_APPLIANCE_VLAN_TYPE 1192 1193 A byte containing the id of the VLAN. 1194 1195- Status LED: CONFIG_STATUS_LED 1196 1197 Several configurations allow to display the current 1198 status using a LED. For instance, the LED will blink 1199 fast while running U-Boot code, stop blinking as 1200 soon as a reply to a BOOTP request was received, and 1201 start blinking slow once the Linux kernel is running 1202 (supported by a status LED driver in the Linux 1203 kernel). Defining CONFIG_STATUS_LED enables this 1204 feature in U-Boot. 1205 1206- CAN Support: CONFIG_CAN_DRIVER 1207 1208 Defining CONFIG_CAN_DRIVER enables CAN driver support 1209 on those systems that support this (optional) 1210 feature, like the TQM8xxL modules. 1211 1212- I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C 1213 1214 These enable I2C serial bus commands. Defining either of 1215 (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will 1216 include the appropriate I2C driver for the selected cpu. 1217 1218 This will allow you to use i2c commands at the u-boot 1219 command line (as long as you set CONFIG_CMD_I2C in 1220 CONFIG_COMMANDS) and communicate with i2c based realtime 1221 clock chips. See common/cmd_i2c.c for a description of the 1222 command line interface. 1223 1224 CONFIG_I2C_CMD_TREE is a recommended option that places 1225 all I2C commands under a single 'i2c' root command. The 1226 older 'imm', 'imd', 'iprobe' etc. commands are considered 1227 deprecated and may disappear in the future. 1228 1229 CONFIG_HARD_I2C selects a hardware I2C controller. 1230 1231 CONFIG_SOFT_I2C configures u-boot to use a software (aka 1232 bit-banging) driver instead of CPM or similar hardware 1233 support for I2C. 1234 1235 There are several other quantities that must also be 1236 defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C. 1237 1238 In both cases you will need to define CFG_I2C_SPEED 1239 to be the frequency (in Hz) at which you wish your i2c bus 1240 to run and CFG_I2C_SLAVE to be the address of this node (ie 1241 the cpu's i2c node address). 1242 1243 Now, the u-boot i2c code for the mpc8xx (cpu/mpc8xx/i2c.c) 1244 sets the cpu up as a master node and so its address should 1245 therefore be cleared to 0 (See, eg, MPC823e User's Manual 1246 p.16-473). So, set CFG_I2C_SLAVE to 0. 1247 1248 That's all that's required for CONFIG_HARD_I2C. 1249 1250 If you use the software i2c interface (CONFIG_SOFT_I2C) 1251 then the following macros need to be defined (examples are 1252 from include/configs/lwmon.h): 1253 1254 I2C_INIT 1255 1256 (Optional). Any commands necessary to enable the I2C 1257 controller or configure ports. 1258 1259 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL) 1260 1261 I2C_PORT 1262 1263 (Only for MPC8260 CPU). The I/O port to use (the code 1264 assumes both bits are on the same port). Valid values 1265 are 0..3 for ports A..D. 1266 1267 I2C_ACTIVE 1268 1269 The code necessary to make the I2C data line active 1270 (driven). If the data line is open collector, this 1271 define can be null. 1272 1273 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA) 1274 1275 I2C_TRISTATE 1276 1277 The code necessary to make the I2C data line tri-stated 1278 (inactive). If the data line is open collector, this 1279 define can be null. 1280 1281 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA) 1282 1283 I2C_READ 1284 1285 Code that returns TRUE if the I2C data line is high, 1286 FALSE if it is low. 1287 1288 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0) 1289 1290 I2C_SDA(bit) 1291 1292 If <bit> is TRUE, sets the I2C data line high. If it 1293 is FALSE, it clears it (low). 1294 1295 eg: #define I2C_SDA(bit) \ 1296 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \ 1297 else immr->im_cpm.cp_pbdat &= ~PB_SDA 1298 1299 I2C_SCL(bit) 1300 1301 If <bit> is TRUE, sets the I2C clock line high. If it 1302 is FALSE, it clears it (low). 1303 1304 eg: #define I2C_SCL(bit) \ 1305 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \ 1306 else immr->im_cpm.cp_pbdat &= ~PB_SCL 1307 1308 I2C_DELAY 1309 1310 This delay is invoked four times per clock cycle so this 1311 controls the rate of data transfer. The data rate thus 1312 is 1 / (I2C_DELAY * 4). Often defined to be something 1313 like: 1314 1315 #define I2C_DELAY udelay(2) 1316 1317 CFG_I2C_INIT_BOARD 1318 1319 When a board is reset during an i2c bus transfer 1320 chips might think that the current transfer is still 1321 in progress. On some boards it is possible to access 1322 the i2c SCLK line directly, either by using the 1323 processor pin as a GPIO or by having a second pin 1324 connected to the bus. If this option is defined a 1325 custom i2c_init_board() routine in boards/xxx/board.c 1326 is run early in the boot sequence. 1327 1328 CONFIG_I2CFAST (PPC405GP|PPC405EP only) 1329 1330 This option enables configuration of bi_iic_fast[] flags 1331 in u-boot bd_info structure based on u-boot environment 1332 variable "i2cfast". (see also i2cfast) 1333 1334 CONFIG_I2C_MULTI_BUS 1335 1336 This option allows the use of multiple I2C buses, each of which 1337 must have a controller. At any point in time, only one bus is 1338 active. To switch to a different bus, use the 'i2c dev' command. 1339 Note that bus numbering is zero-based. 1340 1341 CFG_I2C_NOPROBES 1342 1343 This option specifies a list of I2C devices that will be skipped 1344 when the 'i2c probe' command is issued (or 'iprobe' using the legacy 1345 command). If CONFIG_I2C_MULTI_BUS is set, specify a list of bus-device 1346 pairs. Otherwise, specify a 1D array of device addresses 1347 1348 e.g. 1349 #undef CONFIG_I2C_MULTI_BUS 1350 #define CFG_I2C_NOPROBES {0x50,0x68} 1351 1352 will skip addresses 0x50 and 0x68 on a board with one I2C bus 1353 1354 #define CONFIG_I2C_MULTI_BUS 1355 #define CFG_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}} 1356 1357 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1 1358 1359 CFG_SPD_BUS_NUM 1360 1361 If defined, then this indicates the I2C bus number for DDR SPD. 1362 If not defined, then U-Boot assumes that SPD is on I2C bus 0. 1363 1364 CFG_RTC_BUS_NUM 1365 1366 If defined, then this indicates the I2C bus number for the RTC. 1367 If not defined, then U-Boot assumes that RTC is on I2C bus 0. 1368 1369 CFG_DTT_BUS_NUM 1370 1371 If defined, then this indicates the I2C bus number for the DTT. 1372 If not defined, then U-Boot assumes that DTT is on I2C bus 0. 1373 1374 CONFIG_FSL_I2C 1375 1376 Define this option if you want to use Freescale's I2C driver in 1377 drivers/i2c/fsl_i2c.c. 1378 1379 1380- SPI Support: CONFIG_SPI 1381 1382 Enables SPI driver (so far only tested with 1383 SPI EEPROM, also an instance works with Crystal A/D and 1384 D/As on the SACSng board) 1385 1386 CONFIG_SPI_X 1387 1388 Enables extended (16-bit) SPI EEPROM addressing. 1389 (symmetrical to CONFIG_I2C_X) 1390 1391 CONFIG_SOFT_SPI 1392 1393 Enables a software (bit-bang) SPI driver rather than 1394 using hardware support. This is a general purpose 1395 driver that only requires three general I/O port pins 1396 (two outputs, one input) to function. If this is 1397 defined, the board configuration must define several 1398 SPI configuration items (port pins to use, etc). For 1399 an example, see include/configs/sacsng.h. 1400 1401 CONFIG_HARD_SPI 1402 1403 Enables a hardware SPI driver for general-purpose reads 1404 and writes. As with CONFIG_SOFT_SPI, the board configuration 1405 must define a list of chip-select function pointers. 1406 Currently supported on some MPC8xxx processors. For an 1407 example, see include/configs/mpc8349emds.h. 1408 1409- FPGA Support: CONFIG_FPGA 1410 1411 Enables FPGA subsystem. 1412 1413 CONFIG_FPGA_<vendor> 1414 1415 Enables support for specific chip vendors. 1416 (ALTERA, XILINX) 1417 1418 CONFIG_FPGA_<family> 1419 1420 Enables support for FPGA family. 1421 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX) 1422 1423 CONFIG_FPGA_COUNT 1424 1425 Specify the number of FPGA devices to support. 1426 1427 CFG_FPGA_PROG_FEEDBACK 1428 1429 Enable printing of hash marks during FPGA configuration. 1430 1431 CFG_FPGA_CHECK_BUSY 1432 1433 Enable checks on FPGA configuration interface busy 1434 status by the configuration function. This option 1435 will require a board or device specific function to 1436 be written. 1437 1438 CONFIG_FPGA_DELAY 1439 1440 If defined, a function that provides delays in the FPGA 1441 configuration driver. 1442 1443 CFG_FPGA_CHECK_CTRLC 1444 Allow Control-C to interrupt FPGA configuration 1445 1446 CFG_FPGA_CHECK_ERROR 1447 1448 Check for configuration errors during FPGA bitfile 1449 loading. For example, abort during Virtex II 1450 configuration if the INIT_B line goes low (which 1451 indicated a CRC error). 1452 1453 CFG_FPGA_WAIT_INIT 1454 1455 Maximum time to wait for the INIT_B line to deassert 1456 after PROB_B has been deasserted during a Virtex II 1457 FPGA configuration sequence. The default time is 500 1458 mS. 1459 1460 CFG_FPGA_WAIT_BUSY 1461 1462 Maximum time to wait for BUSY to deassert during 1463 Virtex II FPGA configuration. The default is 5 mS. 1464 1465 CFG_FPGA_WAIT_CONFIG 1466 1467 Time to wait after FPGA configuration. The default is 1468 200 mS. 1469 1470- Configuration Management: 1471 CONFIG_IDENT_STRING 1472 1473 If defined, this string will be added to the U-Boot 1474 version information (U_BOOT_VERSION) 1475 1476- Vendor Parameter Protection: 1477 1478 U-Boot considers the values of the environment 1479 variables "serial#" (Board Serial Number) and 1480 "ethaddr" (Ethernet Address) to be parameters that 1481 are set once by the board vendor / manufacturer, and 1482 protects these variables from casual modification by 1483 the user. Once set, these variables are read-only, 1484 and write or delete attempts are rejected. You can 1485 change this behviour: 1486 1487 If CONFIG_ENV_OVERWRITE is #defined in your config 1488 file, the write protection for vendor parameters is 1489 completely disabled. Anybody can change or delete 1490 these parameters. 1491 1492 Alternatively, if you #define _both_ CONFIG_ETHADDR 1493 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default 1494 ethernet address is installed in the environment, 1495 which can be changed exactly ONCE by the user. [The 1496 serial# is unaffected by this, i. e. it remains 1497 read-only.] 1498 1499- Protected RAM: 1500 CONFIG_PRAM 1501 1502 Define this variable to enable the reservation of 1503 "protected RAM", i. e. RAM which is not overwritten 1504 by U-Boot. Define CONFIG_PRAM to hold the number of 1505 kB you want to reserve for pRAM. You can overwrite 1506 this default value by defining an environment 1507 variable "pram" to the number of kB you want to 1508 reserve. Note that the board info structure will 1509 still show the full amount of RAM. If pRAM is 1510 reserved, a new environment variable "mem" will 1511 automatically be defined to hold the amount of 1512 remaining RAM in a form that can be passed as boot 1513 argument to Linux, for instance like that: 1514 1515 setenv bootargs ... mem=\${mem} 1516 saveenv 1517 1518 This way you can tell Linux not to use this memory, 1519 either, which results in a memory region that will 1520 not be affected by reboots. 1521 1522 *WARNING* If your board configuration uses automatic 1523 detection of the RAM size, you must make sure that 1524 this memory test is non-destructive. So far, the 1525 following board configurations are known to be 1526 "pRAM-clean": 1527 1528 ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL, 1529 HERMES, IP860, RPXlite, LWMON, LANTEC, 1530 PCU_E, FLAGADM, TQM8260 1531 1532- Error Recovery: 1533 CONFIG_PANIC_HANG 1534 1535 Define this variable to stop the system in case of a 1536 fatal error, so that you have to reset it manually. 1537 This is probably NOT a good idea for an embedded 1538 system where you want to system to reboot 1539 automatically as fast as possible, but it may be 1540 useful during development since you can try to debug 1541 the conditions that lead to the situation. 1542 1543 CONFIG_NET_RETRY_COUNT 1544 1545 This variable defines the number of retries for 1546 network operations like ARP, RARP, TFTP, or BOOTP 1547 before giving up the operation. If not defined, a 1548 default value of 5 is used. 1549 1550- Command Interpreter: 1551 CONFIG_AUTO_COMPLETE 1552 1553 Enable auto completion of commands using TAB. 1554 1555 Note that this feature has NOT been implemented yet 1556 for the "hush" shell. 1557 1558 1559 CFG_HUSH_PARSER 1560 1561 Define this variable to enable the "hush" shell (from 1562 Busybox) as command line interpreter, thus enabling 1563 powerful command line syntax like 1564 if...then...else...fi conditionals or `&&' and '||' 1565 constructs ("shell scripts"). 1566 1567 If undefined, you get the old, much simpler behaviour 1568 with a somewhat smaller memory footprint. 1569 1570 1571 CFG_PROMPT_HUSH_PS2 1572 1573 This defines the secondary prompt string, which is 1574 printed when the command interpreter needs more input 1575 to complete a command. Usually "> ". 1576 1577 Note: 1578 1579 In the current implementation, the local variables 1580 space and global environment variables space are 1581 separated. Local variables are those you define by 1582 simply typing `name=value'. To access a local 1583 variable later on, you have write `$name' or 1584 `${name}'; to execute the contents of a variable 1585 directly type `$name' at the command prompt. 1586 1587 Global environment variables are those you use 1588 setenv/printenv to work with. To run a command stored 1589 in such a variable, you need to use the run command, 1590 and you must not use the '$' sign to access them. 1591 1592 To store commands and special characters in a 1593 variable, please use double quotation marks 1594 surrounding the whole text of the variable, instead 1595 of the backslashes before semicolons and special 1596 symbols. 1597 1598- Commandline Editing and History: 1599 CONFIG_CMDLINE_EDITING 1600 1601 Enable editiong and History functions for interactive 1602 commandline input operations 1603 1604- Default Environment: 1605 CONFIG_EXTRA_ENV_SETTINGS 1606 1607 Define this to contain any number of null terminated 1608 strings (variable = value pairs) that will be part of 1609 the default environment compiled into the boot image. 1610 1611 For example, place something like this in your 1612 board's config file: 1613 1614 #define CONFIG_EXTRA_ENV_SETTINGS \ 1615 "myvar1=value1\0" \ 1616 "myvar2=value2\0" 1617 1618 Warning: This method is based on knowledge about the 1619 internal format how the environment is stored by the 1620 U-Boot code. This is NOT an official, exported 1621 interface! Although it is unlikely that this format 1622 will change soon, there is no guarantee either. 1623 You better know what you are doing here. 1624 1625 Note: overly (ab)use of the default environment is 1626 discouraged. Make sure to check other ways to preset 1627 the environment like the autoscript function or the 1628 boot command first. 1629 1630- DataFlash Support: 1631 CONFIG_HAS_DATAFLASH 1632 1633 Defining this option enables DataFlash features and 1634 allows to read/write in Dataflash via the standard 1635 commands cp, md... 1636 1637- SystemACE Support: 1638 CONFIG_SYSTEMACE 1639 1640 Adding this option adds support for Xilinx SystemACE 1641 chips attached via some sort of local bus. The address 1642 of the chip must alsh be defined in the 1643 CFG_SYSTEMACE_BASE macro. For example: 1644 1645 #define CONFIG_SYSTEMACE 1646 #define CFG_SYSTEMACE_BASE 0xf0000000 1647 1648 When SystemACE support is added, the "ace" device type 1649 becomes available to the fat commands, i.e. fatls. 1650 1651- TFTP Fixed UDP Port: 1652 CONFIG_TFTP_PORT 1653 1654 If this is defined, the environment variable tftpsrcp 1655 is used to supply the TFTP UDP source port value. 1656 If tftpsrcp isn't defined, the normal pseudo-random port 1657 number generator is used. 1658 1659 Also, the environment variable tftpdstp is used to supply 1660 the TFTP UDP destination port value. If tftpdstp isn't 1661 defined, the normal port 69 is used. 1662 1663 The purpose for tftpsrcp is to allow a TFTP server to 1664 blindly start the TFTP transfer using the pre-configured 1665 target IP address and UDP port. This has the effect of 1666 "punching through" the (Windows XP) firewall, allowing 1667 the remainder of the TFTP transfer to proceed normally. 1668 A better solution is to properly configure the firewall, 1669 but sometimes that is not allowed. 1670 1671- Show boot progress: 1672 CONFIG_SHOW_BOOT_PROGRESS 1673 1674 Defining this option allows to add some board- 1675 specific code (calling a user-provided function 1676 "show_boot_progress(int)") that enables you to show 1677 the system's boot progress on some display (for 1678 example, some LED's) on your board. At the moment, 1679 the following checkpoints are implemented: 1680 1681 Arg Where When 1682 1 common/cmd_bootm.c before attempting to boot an image 1683 -1 common/cmd_bootm.c Image header has bad magic number 1684 2 common/cmd_bootm.c Image header has correct magic number 1685 -2 common/cmd_bootm.c Image header has bad checksum 1686 3 common/cmd_bootm.c Image header has correct checksum 1687 -3 common/cmd_bootm.c Image data has bad checksum 1688 4 common/cmd_bootm.c Image data has correct checksum 1689 -4 common/cmd_bootm.c Image is for unsupported architecture 1690 5 common/cmd_bootm.c Architecture check OK 1691 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi, standalone) 1692 6 common/cmd_bootm.c Image Type check OK 1693 -6 common/cmd_bootm.c gunzip uncompression error 1694 -7 common/cmd_bootm.c Unimplemented compression type 1695 7 common/cmd_bootm.c Uncompression OK 1696 -8 common/cmd_bootm.c Wrong Image Type (not kernel, multi, standalone) 1697 8 common/cmd_bootm.c Image Type check OK 1698 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX) 1699 9 common/cmd_bootm.c Start initial ramdisk verification 1700 -10 common/cmd_bootm.c Ramdisk header has bad magic number 1701 -11 common/cmd_bootm.c Ramdisk header has bad checksum 1702 10 common/cmd_bootm.c Ramdisk header is OK 1703 -12 common/cmd_bootm.c Ramdisk data has bad checksum 1704 11 common/cmd_bootm.c Ramdisk data has correct checksum 1705 12 common/cmd_bootm.c Ramdisk verification complete, start loading 1706 -13 common/cmd_bootm.c Wrong Image Type (not PPC Linux Ramdisk) 1707 13 common/cmd_bootm.c Start multifile image verification 1708 14 common/cmd_bootm.c No initial ramdisk, no multifile, continue. 1709 15 common/cmd_bootm.c All preparation done, transferring control to OS 1710 1711 -30 lib_ppc/board.c Fatal error, hang the system 1712 -31 post/post.c POST test failed, detected by post_output_backlog() 1713 -32 post/post.c POST test failed, detected by post_run_single() 1714 1715 34 common/cmd_doc.c before loading a Image from a DOC device 1716 -35 common/cmd_doc.c Bad usage of "doc" command 1717 35 common/cmd_doc.c correct usage of "doc" command 1718 -36 common/cmd_doc.c No boot device 1719 36 common/cmd_doc.c correct boot device 1720 -37 common/cmd_doc.c Unknown Chip ID on boot device 1721 37 common/cmd_doc.c correct chip ID found, device available 1722 -38 common/cmd_doc.c Read Error on boot device 1723 38 common/cmd_doc.c reading Image header from DOC device OK 1724 -39 common/cmd_doc.c Image header has bad magic number 1725 39 common/cmd_doc.c Image header has correct magic number 1726 -40 common/cmd_doc.c Error reading Image from DOC device 1727 40 common/cmd_doc.c Image header has correct magic number 1728 41 common/cmd_ide.c before loading a Image from a IDE device 1729 -42 common/cmd_ide.c Bad usage of "ide" command 1730 42 common/cmd_ide.c correct usage of "ide" command 1731 -43 common/cmd_ide.c No boot device 1732 43 common/cmd_ide.c boot device found 1733 -44 common/cmd_ide.c Device not available 1734 44 common/cmd_ide.c Device available 1735 -45 common/cmd_ide.c wrong partition selected 1736 45 common/cmd_ide.c partition selected 1737 -46 common/cmd_ide.c Unknown partition table 1738 46 common/cmd_ide.c valid partition table found 1739 -47 common/cmd_ide.c Invalid partition type 1740 47 common/cmd_ide.c correct partition type 1741 -48 common/cmd_ide.c Error reading Image Header on boot device 1742 48 common/cmd_ide.c reading Image Header from IDE device OK 1743 -49 common/cmd_ide.c Image header has bad magic number 1744 49 common/cmd_ide.c Image header has correct magic number 1745 -50 common/cmd_ide.c Image header has bad checksum 1746 50 common/cmd_ide.c Image header has correct checksum 1747 -51 common/cmd_ide.c Error reading Image from IDE device 1748 51 common/cmd_ide.c reading Image from IDE device OK 1749 52 common/cmd_nand.c before loading a Image from a NAND device 1750 -53 common/cmd_nand.c Bad usage of "nand" command 1751 53 common/cmd_nand.c correct usage of "nand" command 1752 -54 common/cmd_nand.c No boot device 1753 54 common/cmd_nand.c boot device found 1754 -55 common/cmd_nand.c Unknown Chip ID on boot device 1755 55 common/cmd_nand.c correct chip ID found, device available 1756 -56 common/cmd_nand.c Error reading Image Header on boot device 1757 56 common/cmd_nand.c reading Image Header from NAND device OK 1758 -57 common/cmd_nand.c Image header has bad magic number 1759 57 common/cmd_nand.c Image header has correct magic number 1760 -58 common/cmd_nand.c Error reading Image from NAND device 1761 58 common/cmd_nand.c reading Image from NAND device OK 1762 1763 -60 common/env_common.c Environment has a bad CRC, using default 1764 1765 64 net/eth.c starting with Ethernetconfiguration. 1766 -64 net/eth.c no Ethernet found. 1767 65 net/eth.c Ethernet found. 1768 1769 -80 common/cmd_net.c usage wrong 1770 80 common/cmd_net.c before calling NetLoop() 1771 -81 common/cmd_net.c some error in NetLoop() occured 1772 81 common/cmd_net.c NetLoop() back without error 1773 -82 common/cmd_net.c size == 0 (File with size 0 loaded) 1774 82 common/cmd_net.c trying automatic boot 1775 83 common/cmd_net.c running autoscript 1776 -83 common/cmd_net.c some error in automatic boot or autoscript 1777 84 common/cmd_net.c end without errors 1778 1779Modem Support: 1780-------------- 1781 1782[so far only for SMDK2400 and TRAB boards] 1783 1784- Modem support endable: 1785 CONFIG_MODEM_SUPPORT 1786 1787- RTS/CTS Flow control enable: 1788 CONFIG_HWFLOW 1789 1790- Modem debug support: 1791 CONFIG_MODEM_SUPPORT_DEBUG 1792 1793 Enables debugging stuff (char screen[1024], dbg()) 1794 for modem support. Useful only with BDI2000. 1795 1796- Interrupt support (PPC): 1797 1798 There are common interrupt_init() and timer_interrupt() 1799 for all PPC archs. interrupt_init() calls interrupt_init_cpu() 1800 for cpu specific initialization. interrupt_init_cpu() 1801 should set decrementer_count to appropriate value. If 1802 cpu resets decrementer automatically after interrupt 1803 (ppc4xx) it should set decrementer_count to zero. 1804 timer_interrupt() calls timer_interrupt_cpu() for cpu 1805 specific handling. If board has watchdog / status_led 1806 / other_activity_monitor it works automatically from 1807 general timer_interrupt(). 1808 1809- General: 1810 1811 In the target system modem support is enabled when a 1812 specific key (key combination) is pressed during 1813 power-on. Otherwise U-Boot will boot normally 1814 (autoboot). The key_pressed() fuction is called from 1815 board_init(). Currently key_pressed() is a dummy 1816 function, returning 1 and thus enabling modem 1817 initialization. 1818 1819 If there are no modem init strings in the 1820 environment, U-Boot proceed to autoboot; the 1821 previous output (banner, info printfs) will be 1822 supressed, though. 1823 1824 See also: doc/README.Modem 1825 1826 1827Configuration Settings: 1828----------------------- 1829 1830- CFG_LONGHELP: Defined when you want long help messages included; 1831 undefine this when you're short of memory. 1832 1833- CFG_PROMPT: This is what U-Boot prints on the console to 1834 prompt for user input. 1835 1836- CFG_CBSIZE: Buffer size for input from the Console 1837 1838- CFG_PBSIZE: Buffer size for Console output 1839 1840- CFG_MAXARGS: max. Number of arguments accepted for monitor commands 1841 1842- CFG_BARGSIZE: Buffer size for Boot Arguments which are passed to 1843 the application (usually a Linux kernel) when it is 1844 booted 1845 1846- CFG_BAUDRATE_TABLE: 1847 List of legal baudrate settings for this board. 1848 1849- CFG_CONSOLE_INFO_QUIET 1850 Suppress display of console information at boot. 1851 1852- CFG_CONSOLE_IS_IN_ENV 1853 If the board specific function 1854 extern int overwrite_console (void); 1855 returns 1, the stdin, stderr and stdout are switched to the 1856 serial port, else the settings in the environment are used. 1857 1858- CFG_CONSOLE_OVERWRITE_ROUTINE 1859 Enable the call to overwrite_console(). 1860 1861- CFG_CONSOLE_ENV_OVERWRITE 1862 Enable overwrite of previous console environment settings. 1863 1864- CFG_MEMTEST_START, CFG_MEMTEST_END: 1865 Begin and End addresses of the area used by the 1866 simple memory test. 1867 1868- CFG_ALT_MEMTEST: 1869 Enable an alternate, more extensive memory test. 1870 1871- CFG_MEMTEST_SCRATCH: 1872 Scratch address used by the alternate memory test 1873 You only need to set this if address zero isn't writeable 1874 1875- CFG_TFTP_LOADADDR: 1876 Default load address for network file downloads 1877 1878- CFG_LOADS_BAUD_CHANGE: 1879 Enable temporary baudrate change while serial download 1880 1881- CFG_SDRAM_BASE: 1882 Physical start address of SDRAM. _Must_ be 0 here. 1883 1884- CFG_MBIO_BASE: 1885 Physical start address of Motherboard I/O (if using a 1886 Cogent motherboard) 1887 1888- CFG_FLASH_BASE: 1889 Physical start address of Flash memory. 1890 1891- CFG_MONITOR_BASE: 1892 Physical start address of boot monitor code (set by 1893 make config files to be same as the text base address 1894 (TEXT_BASE) used when linking) - same as 1895 CFG_FLASH_BASE when booting from flash. 1896 1897- CFG_MONITOR_LEN: 1898 Size of memory reserved for monitor code, used to 1899 determine _at_compile_time_ (!) if the environment is 1900 embedded within the U-Boot image, or in a separate 1901 flash sector. 1902 1903- CFG_MALLOC_LEN: 1904 Size of DRAM reserved for malloc() use. 1905 1906- CFG_BOOTM_LEN: 1907 Normally compressed uImages are limited to an 1908 uncompressed size of 8 MBytes. If this is not enough, 1909 you can define CFG_BOOTM_LEN in your board config file 1910 to adjust this setting to your needs. 1911 1912- CFG_BOOTMAPSZ: 1913 Maximum size of memory mapped by the startup code of 1914 the Linux kernel; all data that must be processed by 1915 the Linux kernel (bd_info, boot arguments, eventually 1916 initrd image) must be put below this limit. 1917 1918- CFG_MAX_FLASH_BANKS: 1919 Max number of Flash memory banks 1920 1921- CFG_MAX_FLASH_SECT: 1922 Max number of sectors on a Flash chip 1923 1924- CFG_FLASH_ERASE_TOUT: 1925 Timeout for Flash erase operations (in ms) 1926 1927- CFG_FLASH_WRITE_TOUT: 1928 Timeout for Flash write operations (in ms) 1929 1930- CFG_FLASH_LOCK_TOUT 1931 Timeout for Flash set sector lock bit operation (in ms) 1932 1933- CFG_FLASH_UNLOCK_TOUT 1934 Timeout for Flash clear lock bits operation (in ms) 1935 1936- CFG_FLASH_PROTECTION 1937 If defined, hardware flash sectors protection is used 1938 instead of U-Boot software protection. 1939 1940- CFG_DIRECT_FLASH_TFTP: 1941 1942 Enable TFTP transfers directly to flash memory; 1943 without this option such a download has to be 1944 performed in two steps: (1) download to RAM, and (2) 1945 copy from RAM to flash. 1946 1947 The two-step approach is usually more reliable, since 1948 you can check if the download worked before you erase 1949 the flash, but in some situations (when sytem RAM is 1950 too limited to allow for a tempory copy of the 1951 downloaded image) this option may be very useful. 1952 1953- CFG_FLASH_CFI: 1954 Define if the flash driver uses extra elements in the 1955 common flash structure for storing flash geometry. 1956 1957- CFG_FLASH_CFI_DRIVER 1958 This option also enables the building of the cfi_flash driver 1959 in the drivers directory 1960 1961- CFG_FLASH_QUIET_TEST 1962 If this option is defined, the common CFI flash doesn't 1963 print it's warning upon not recognized FLASH banks. This 1964 is useful, if some of the configured banks are only 1965 optionally available. 1966 1967- CONFIG_FLASH_SHOW_PROGRESS 1968 If defined (must be an integer), print out countdown 1969 digits and dots. Recommended value: 45 (9..1) for 80 1970 column displays, 15 (3..1) for 40 column displays. 1971 1972- CFG_RX_ETH_BUFFER: 1973 Defines the number of ethernet receive buffers. On some 1974 ethernet controllers it is recommended to set this value 1975 to 8 or even higher (EEPRO100 or 405 EMAC), since all 1976 buffers can be full shortly after enabling the interface 1977 on high ethernet traffic. 1978 Defaults to 4 if not defined. 1979 1980The following definitions that deal with the placement and management 1981of environment data (variable area); in general, we support the 1982following configurations: 1983 1984- CFG_ENV_IS_IN_FLASH: 1985 1986 Define this if the environment is in flash memory. 1987 1988 a) The environment occupies one whole flash sector, which is 1989 "embedded" in the text segment with the U-Boot code. This 1990 happens usually with "bottom boot sector" or "top boot 1991 sector" type flash chips, which have several smaller 1992 sectors at the start or the end. For instance, such a 1993 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In 1994 such a case you would place the environment in one of the 1995 4 kB sectors - with U-Boot code before and after it. With 1996 "top boot sector" type flash chips, you would put the 1997 environment in one of the last sectors, leaving a gap 1998 between U-Boot and the environment. 1999 2000 - CFG_ENV_OFFSET: 2001 2002 Offset of environment data (variable area) to the 2003 beginning of flash memory; for instance, with bottom boot 2004 type flash chips the second sector can be used: the offset 2005 for this sector is given here. 2006 2007 CFG_ENV_OFFSET is used relative to CFG_FLASH_BASE. 2008 2009 - CFG_ENV_ADDR: 2010 2011 This is just another way to specify the start address of 2012 the flash sector containing the environment (instead of 2013 CFG_ENV_OFFSET). 2014 2015 - CFG_ENV_SECT_SIZE: 2016 2017 Size of the sector containing the environment. 2018 2019 2020 b) Sometimes flash chips have few, equal sized, BIG sectors. 2021 In such a case you don't want to spend a whole sector for 2022 the environment. 2023 2024 - CFG_ENV_SIZE: 2025 2026 If you use this in combination with CFG_ENV_IS_IN_FLASH 2027 and CFG_ENV_SECT_SIZE, you can specify to use only a part 2028 of this flash sector for the environment. This saves 2029 memory for the RAM copy of the environment. 2030 2031 It may also save flash memory if you decide to use this 2032 when your environment is "embedded" within U-Boot code, 2033 since then the remainder of the flash sector could be used 2034 for U-Boot code. It should be pointed out that this is 2035 STRONGLY DISCOURAGED from a robustness point of view: 2036 updating the environment in flash makes it always 2037 necessary to erase the WHOLE sector. If something goes 2038 wrong before the contents has been restored from a copy in 2039 RAM, your target system will be dead. 2040 2041 - CFG_ENV_ADDR_REDUND 2042 CFG_ENV_SIZE_REDUND 2043 2044 These settings describe a second storage area used to hold 2045 a redundand copy of the environment data, so that there is 2046 a valid backup copy in case there is a power failure during 2047 a "saveenv" operation. 2048 2049BE CAREFUL! Any changes to the flash layout, and some changes to the 2050source code will make it necessary to adapt <board>/u-boot.lds* 2051accordingly! 2052 2053 2054- CFG_ENV_IS_IN_NVRAM: 2055 2056 Define this if you have some non-volatile memory device 2057 (NVRAM, battery buffered SRAM) which you want to use for the 2058 environment. 2059 2060 - CFG_ENV_ADDR: 2061 - CFG_ENV_SIZE: 2062 2063 These two #defines are used to determin the memory area you 2064 want to use for environment. It is assumed that this memory 2065 can just be read and written to, without any special 2066 provision. 2067 2068BE CAREFUL! The first access to the environment happens quite early 2069in U-Boot initalization (when we try to get the setting of for the 2070console baudrate). You *MUST* have mappend your NVRAM area then, or 2071U-Boot will hang. 2072 2073Please note that even with NVRAM we still use a copy of the 2074environment in RAM: we could work on NVRAM directly, but we want to 2075keep settings there always unmodified except somebody uses "saveenv" 2076to save the current settings. 2077 2078 2079- CFG_ENV_IS_IN_EEPROM: 2080 2081 Use this if you have an EEPROM or similar serial access 2082 device and a driver for it. 2083 2084 - CFG_ENV_OFFSET: 2085 - CFG_ENV_SIZE: 2086 2087 These two #defines specify the offset and size of the 2088 environment area within the total memory of your EEPROM. 2089 2090 - CFG_I2C_EEPROM_ADDR: 2091 If defined, specified the chip address of the EEPROM device. 2092 The default address is zero. 2093 2094 - CFG_EEPROM_PAGE_WRITE_BITS: 2095 If defined, the number of bits used to address bytes in a 2096 single page in the EEPROM device. A 64 byte page, for example 2097 would require six bits. 2098 2099 - CFG_EEPROM_PAGE_WRITE_DELAY_MS: 2100 If defined, the number of milliseconds to delay between 2101 page writes. The default is zero milliseconds. 2102 2103 - CFG_I2C_EEPROM_ADDR_LEN: 2104 The length in bytes of the EEPROM memory array address. Note 2105 that this is NOT the chip address length! 2106 2107 - CFG_I2C_EEPROM_ADDR_OVERFLOW: 2108 EEPROM chips that implement "address overflow" are ones 2109 like Catalyst 24WC04/08/16 which has 9/10/11 bits of 2110 address and the extra bits end up in the "chip address" bit 2111 slots. This makes a 24WC08 (1Kbyte) chip look like four 256 2112 byte chips. 2113 2114 Note that we consider the length of the address field to 2115 still be one byte because the extra address bits are hidden 2116 in the chip address. 2117 2118 - CFG_EEPROM_SIZE: 2119 The size in bytes of the EEPROM device. 2120 2121 2122- CFG_ENV_IS_IN_DATAFLASH: 2123 2124 Define this if you have a DataFlash memory device which you 2125 want to use for the environment. 2126 2127 - CFG_ENV_OFFSET: 2128 - CFG_ENV_ADDR: 2129 - CFG_ENV_SIZE: 2130 2131 These three #defines specify the offset and size of the 2132 environment area within the total memory of your DataFlash placed 2133 at the specified address. 2134 2135- CFG_ENV_IS_IN_NAND: 2136 2137 Define this if you have a NAND device which you want to use 2138 for the environment. 2139 2140 - CFG_ENV_OFFSET: 2141 - CFG_ENV_SIZE: 2142 2143 These two #defines specify the offset and size of the environment 2144 area within the first NAND device. 2145 2146 - CFG_ENV_OFFSET_REDUND 2147 2148 This setting describes a second storage area of CFG_ENV_SIZE 2149 size used to hold a redundant copy of the environment data, 2150 so that there is a valid backup copy in case there is a 2151 power failure during a "saveenv" operation. 2152 2153 Note: CFG_ENV_OFFSET and CFG_ENV_OFFSET_REDUND must be aligned 2154 to a block boundary, and CFG_ENV_SIZE must be a multiple of 2155 the NAND devices block size. 2156 2157- CFG_SPI_INIT_OFFSET 2158 2159 Defines offset to the initial SPI buffer area in DPRAM. The 2160 area is used at an early stage (ROM part) if the environment 2161 is configured to reside in the SPI EEPROM: We need a 520 byte 2162 scratch DPRAM area. It is used between the two initialization 2163 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems 2164 to be a good choice since it makes it far enough from the 2165 start of the data area as well as from the stack pointer. 2166 2167Please note that the environment is read-only until the monitor 2168has been relocated to RAM and a RAM copy of the environment has been 2169created; also, when using EEPROM you will have to use getenv_r() 2170until then to read environment variables. 2171 2172The environment is protected by a CRC32 checksum. Before the monitor 2173is relocated into RAM, as a result of a bad CRC you will be working 2174with the compiled-in default environment - *silently*!!! [This is 2175necessary, because the first environment variable we need is the 2176"baudrate" setting for the console - if we have a bad CRC, we don't 2177have any device yet where we could complain.] 2178 2179Note: once the monitor has been relocated, then it will complain if 2180the default environment is used; a new CRC is computed as soon as you 2181use the "saveenv" command to store a valid environment. 2182 2183- CFG_FAULT_ECHO_LINK_DOWN: 2184 Echo the inverted Ethernet link state to the fault LED. 2185 2186 Note: If this option is active, then CFG_FAULT_MII_ADDR 2187 also needs to be defined. 2188 2189- CFG_FAULT_MII_ADDR: 2190 MII address of the PHY to check for the Ethernet link state. 2191 2192- CFG_64BIT_VSPRINTF: 2193 Makes vsprintf (and all *printf functions) support printing 2194 of 64bit values by using the L quantifier 2195 2196- CFG_64BIT_STRTOUL: 2197 Adds simple_strtoull that returns a 64bit value 2198 2199Low Level (hardware related) configuration options: 2200--------------------------------------------------- 2201 2202- CFG_CACHELINE_SIZE: 2203 Cache Line Size of the CPU. 2204 2205- CFG_DEFAULT_IMMR: 2206 Default address of the IMMR after system reset. 2207 2208 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU, 2209 and RPXsuper) to be able to adjust the position of 2210 the IMMR register after a reset. 2211 2212- Floppy Disk Support: 2213 CFG_FDC_DRIVE_NUMBER 2214 2215 the default drive number (default value 0) 2216 2217 CFG_ISA_IO_STRIDE 2218 2219 defines the spacing between fdc chipset registers 2220 (default value 1) 2221 2222 CFG_ISA_IO_OFFSET 2223 2224 defines the offset of register from address. It 2225 depends on which part of the data bus is connected to 2226 the fdc chipset. (default value 0) 2227 2228 If CFG_ISA_IO_STRIDE CFG_ISA_IO_OFFSET and 2229 CFG_FDC_DRIVE_NUMBER are undefined, they take their 2230 default value. 2231 2232 if CFG_FDC_HW_INIT is defined, then the function 2233 fdc_hw_init() is called at the beginning of the FDC 2234 setup. fdc_hw_init() must be provided by the board 2235 source code. It is used to make hardware dependant 2236 initializations. 2237 2238- CFG_IMMR: Physical address of the Internal Memory. 2239 DO NOT CHANGE unless you know exactly what you're 2240 doing! (11-4) [MPC8xx/82xx systems only] 2241 2242- CFG_INIT_RAM_ADDR: 2243 2244 Start address of memory area that can be used for 2245 initial data and stack; please note that this must be 2246 writable memory that is working WITHOUT special 2247 initialization, i. e. you CANNOT use normal RAM which 2248 will become available only after programming the 2249 memory controller and running certain initialization 2250 sequences. 2251 2252 U-Boot uses the following memory types: 2253 - MPC8xx and MPC8260: IMMR (internal memory of the CPU) 2254 - MPC824X: data cache 2255 - PPC4xx: data cache 2256 2257- CFG_GBL_DATA_OFFSET: 2258 2259 Offset of the initial data structure in the memory 2260 area defined by CFG_INIT_RAM_ADDR. Usually 2261 CFG_GBL_DATA_OFFSET is chosen such that the initial 2262 data is located at the end of the available space 2263 (sometimes written as (CFG_INIT_RAM_END - 2264 CFG_INIT_DATA_SIZE), and the initial stack is just 2265 below that area (growing from (CFG_INIT_RAM_ADDR + 2266 CFG_GBL_DATA_OFFSET) downward. 2267 2268 Note: 2269 On the MPC824X (or other systems that use the data 2270 cache for initial memory) the address chosen for 2271 CFG_INIT_RAM_ADDR is basically arbitrary - it must 2272 point to an otherwise UNUSED address space between 2273 the top of RAM and the start of the PCI space. 2274 2275- CFG_SIUMCR: SIU Module Configuration (11-6) 2276 2277- CFG_SYPCR: System Protection Control (11-9) 2278 2279- CFG_TBSCR: Time Base Status and Control (11-26) 2280 2281- CFG_PISCR: Periodic Interrupt Status and Control (11-31) 2282 2283- CFG_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30) 2284 2285- CFG_SCCR: System Clock and reset Control Register (15-27) 2286 2287- CFG_OR_TIMING_SDRAM: 2288 SDRAM timing 2289 2290- CFG_MAMR_PTA: 2291 periodic timer for refresh 2292 2293- CFG_DER: Debug Event Register (37-47) 2294 2295- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CFG_REMAP_OR_AM, 2296 CFG_PRELIM_OR_AM, CFG_OR_TIMING_FLASH, CFG_OR0_REMAP, 2297 CFG_OR0_PRELIM, CFG_BR0_PRELIM, CFG_OR1_REMAP, CFG_OR1_PRELIM, 2298 CFG_BR1_PRELIM: 2299 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH) 2300 2301- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE, 2302 CFG_OR_TIMING_SDRAM, CFG_OR2_PRELIM, CFG_BR2_PRELIM, 2303 CFG_OR3_PRELIM, CFG_BR3_PRELIM: 2304 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM) 2305 2306- CFG_MAMR_PTA, CFG_MPTPR_2BK_4K, CFG_MPTPR_1BK_4K, CFG_MPTPR_2BK_8K, 2307 CFG_MPTPR_1BK_8K, CFG_MAMR_8COL, CFG_MAMR_9COL: 2308 Machine Mode Register and Memory Periodic Timer 2309 Prescaler definitions (SDRAM timing) 2310 2311- CFG_I2C_UCODE_PATCH, CFG_I2C_DPMEM_OFFSET [0x1FC0]: 2312 enable I2C microcode relocation patch (MPC8xx); 2313 define relocation offset in DPRAM [DSP2] 2314 2315- CFG_SMC_UCODE_PATCH, CFG_SMC_DPMEM_OFFSET [0x1FC0]: 2316 enable SMC microcode relocation patch (MPC8xx); 2317 define relocation offset in DPRAM [SMC1] 2318 2319- CFG_SPI_UCODE_PATCH, CFG_SPI_DPMEM_OFFSET [0x1FC0]: 2320 enable SPI microcode relocation patch (MPC8xx); 2321 define relocation offset in DPRAM [SCC4] 2322 2323- CFG_USE_OSCCLK: 2324 Use OSCM clock mode on MBX8xx board. Be careful, 2325 wrong setting might damage your board. Read 2326 doc/README.MBX before setting this variable! 2327 2328- CFG_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only) 2329 Offset of the bootmode word in DPRAM used by post 2330 (Power On Self Tests). This definition overrides 2331 #define'd default value in commproc.h resp. 2332 cpm_8260.h. 2333 2334- CFG_PCI_SLV_MEM_LOCAL, CFG_PCI_SLV_MEM_BUS, CFG_PICMR0_MASK_ATTRIB, 2335 CFG_PCI_MSTR0_LOCAL, CFG_PCIMSK0_MASK, CFG_PCI_MSTR1_LOCAL, 2336 CFG_PCIMSK1_MASK, CFG_PCI_MSTR_MEM_LOCAL, CFG_PCI_MSTR_MEM_BUS, 2337 CFG_CPU_PCI_MEM_START, CFG_PCI_MSTR_MEM_SIZE, CFG_POCMR0_MASK_ATTRIB, 2338 CFG_PCI_MSTR_MEMIO_LOCAL, CFG_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START, 2339 CFG_PCI_MSTR_MEMIO_SIZE, CFG_POCMR1_MASK_ATTRIB, CFG_PCI_MSTR_IO_LOCAL, 2340 CFG_PCI_MSTR_IO_BUS, CFG_CPU_PCI_IO_START, CFG_PCI_MSTR_IO_SIZE, 2341 CFG_POCMR2_MASK_ATTRIB: (MPC826x only) 2342 Overrides the default PCI memory map in cpu/mpc8260/pci.c if set. 2343 2344- CONFIG_SPD_EEPROM 2345 Get DDR timing information from an I2C EEPROM. Common 2346 with pluggable memory modules such as SODIMMs 2347 2348 SPD_EEPROM_ADDRESS 2349 I2C address of the SPD EEPROM 2350 2351- CFG_SPD_BUS_NUM 2352 If SPD EEPROM is on an I2C bus other than the first 2353 one, specify here. Note that the value must resolve 2354 to something your driver can deal with. 2355 2356- CFG_83XX_DDR_USES_CS0 2357 Only for 83xx systems. If specified, then DDR should 2358 be configured using CS0 and CS1 instead of CS2 and CS3. 2359 2360- CFG_83XX_DDR_USES_CS0 2361 Only for 83xx systems. If specified, then DDR should 2362 be configured using CS0 and CS1 instead of CS2 and CS3. 2363 2364- CONFIG_ETHER_ON_FEC[12] 2365 Define to enable FEC[12] on a 8xx series processor. 2366 2367- CONFIG_FEC[12]_PHY 2368 Define to the hardcoded PHY address which corresponds 2369 to the given FEC; i. e. 2370 #define CONFIG_FEC1_PHY 4 2371 means that the PHY with address 4 is connected to FEC1 2372 2373 When set to -1, means to probe for first available. 2374 2375- CONFIG_FEC[12]_PHY_NORXERR 2376 The PHY does not have a RXERR line (RMII only). 2377 (so program the FEC to ignore it). 2378 2379- CONFIG_RMII 2380 Enable RMII mode for all FECs. 2381 Note that this is a global option, we can't 2382 have one FEC in standard MII mode and another in RMII mode. 2383 2384- CONFIG_CRC32_VERIFY 2385 Add a verify option to the crc32 command. 2386 The syntax is: 2387 2388 => crc32 -v <address> <count> <crc32> 2389 2390 Where address/count indicate a memory area 2391 and crc32 is the correct crc32 which the 2392 area should have. 2393 2394- CONFIG_LOOPW 2395 Add the "loopw" memory command. This only takes effect if 2396 the memory commands are activated globally (CONFIG_CMD_MEM). 2397 2398- CONFIG_MX_CYCLIC 2399 Add the "mdc" and "mwc" memory commands. These are cyclic 2400 "md/mw" commands. 2401 Examples: 2402 2403 => mdc.b 10 4 500 2404 This command will print 4 bytes (10,11,12,13) each 500 ms. 2405 2406 => mwc.l 100 12345678 10 2407 This command will write 12345678 to address 100 all 10 ms. 2408 2409 This only takes effect if the memory commands are activated 2410 globally (CONFIG_CMD_MEM). 2411 2412- CONFIG_SKIP_LOWLEVEL_INIT 2413- CONFIG_SKIP_RELOCATE_UBOOT 2414 2415 [ARM only] If these variables are defined, then 2416 certain low level initializations (like setting up 2417 the memory controller) are omitted and/or U-Boot does 2418 not relocate itself into RAM. 2419 Normally these variables MUST NOT be defined. The 2420 only exception is when U-Boot is loaded (to RAM) by 2421 some other boot loader or by a debugger which 2422 performs these intializations itself. 2423 2424 2425Building the Software: 2426====================== 2427 2428Building U-Boot has been tested in several native build environments 2429and in many different cross environments. Of course we cannot support 2430all possibly existing versions of cross development tools in all 2431(potentially obsolete) versions. In case of tool chain problems we 2432recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK) 2433which is extensively used to build and test U-Boot. 2434 2435If you are not using a native environment, it is assumed that you 2436have GNU cross compiling tools available in your path. In this case, 2437you must set the environment variable CROSS_COMPILE in your shell. 2438Note that no changes to the Makefile or any other source files are 2439necessary. For example using the ELDK on a 4xx CPU, please enter: 2440 2441 $ CROSS_COMPILE=ppc_4xx- 2442 $ export CROSS_COMPILE 2443 2444U-Boot is intended to be simple to build. After installing the 2445sources you must configure U-Boot for one specific board type. This 2446is done by typing: 2447 2448 make NAME_config 2449 2450where "NAME_config" is the name of one of the existing configu- 2451rations; see the main Makefile for supported names. 2452 2453Note: for some board special configuration names may exist; check if 2454 additional information is available from the board vendor; for 2455 instance, the TQM823L systems are available without (standard) 2456 or with LCD support. You can select such additional "features" 2457 when chosing the configuration, i. e. 2458 2459 make TQM823L_config 2460 - will configure for a plain TQM823L, i. e. no LCD support 2461 2462 make TQM823L_LCD_config 2463 - will configure for a TQM823L with U-Boot console on LCD 2464 2465 etc. 2466 2467 2468Finally, type "make all", and you should get some working U-Boot 2469images ready for download to / installation on your system: 2470 2471- "u-boot.bin" is a raw binary image 2472- "u-boot" is an image in ELF binary format 2473- "u-boot.srec" is in Motorola S-Record format 2474 2475By default the build is performed locally and the objects are saved 2476in the source directory. One of the two methods can be used to change 2477this behavior and build U-Boot to some external directory: 2478 24791. Add O= to the make command line invocations: 2480 2481 make O=/tmp/build distclean 2482 make O=/tmp/build NAME_config 2483 make O=/tmp/build all 2484 24852. Set environment variable BUILD_DIR to point to the desired location: 2486 2487 export BUILD_DIR=/tmp/build 2488 make distclean 2489 make NAME_config 2490 make all 2491 2492Note that the command line "O=" setting overrides the BUILD_DIR environment 2493variable. 2494 2495 2496Please be aware that the Makefiles assume you are using GNU make, so 2497for instance on NetBSD you might need to use "gmake" instead of 2498native "make". 2499 2500 2501If the system board that you have is not listed, then you will need 2502to port U-Boot to your hardware platform. To do this, follow these 2503steps: 2504 25051. Add a new configuration option for your board to the toplevel 2506 "Makefile" and to the "MAKEALL" script, using the existing 2507 entries as examples. Note that here and at many other places 2508 boards and other names are listed in alphabetical sort order. Please 2509 keep this order. 25102. Create a new directory to hold your board specific code. Add any 2511 files you need. In your board directory, you will need at least 2512 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds". 25133. Create a new configuration file "include/configs/<board>.h" for 2514 your board 25153. If you're porting U-Boot to a new CPU, then also create a new 2516 directory to hold your CPU specific code. Add any files you need. 25174. Run "make <board>_config" with your new name. 25185. Type "make", and you should get a working "u-boot.srec" file 2519 to be installed on your target system. 25206. Debug and solve any problems that might arise. 2521 [Of course, this last step is much harder than it sounds.] 2522 2523 2524Testing of U-Boot Modifications, Ports to New Hardware, etc.: 2525============================================================== 2526 2527If you have modified U-Boot sources (for instance added a new board 2528or support for new devices, a new CPU, etc.) you are expected to 2529provide feedback to the other developers. The feedback normally takes 2530the form of a "patch", i. e. a context diff against a certain (latest 2531official or latest in the git repository) version of U-Boot sources. 2532 2533But before you submit such a patch, please verify that your modifi- 2534cation did not break existing code. At least make sure that *ALL* of 2535the supported boards compile WITHOUT ANY compiler warnings. To do so, 2536just run the "MAKEALL" script, which will configure and build U-Boot 2537for ALL supported system. Be warned, this will take a while. You can 2538select which (cross) compiler to use by passing a `CROSS_COMPILE' 2539environment variable to the script, i. e. to use the ELDK cross tools 2540you can type 2541 2542 CROSS_COMPILE=ppc_8xx- MAKEALL 2543 2544or to build on a native PowerPC system you can type 2545 2546 CROSS_COMPILE=' ' MAKEALL 2547 2548When using the MAKEALL script, the default behaviour is to build 2549U-Boot in the source directory. This location can be changed by 2550setting the BUILD_DIR environment variable. Also, for each target 2551built, the MAKEALL script saves two log files (<target>.ERR and 2552<target>.MAKEALL) in the <source dir>/LOG directory. This default 2553location can be changed by setting the MAKEALL_LOGDIR environment 2554variable. For example: 2555 2556 export BUILD_DIR=/tmp/build 2557 export MAKEALL_LOGDIR=/tmp/log 2558 CROSS_COMPILE=ppc_8xx- MAKEALL 2559 2560With the above settings build objects are saved in the /tmp/build, 2561log files are saved in the /tmp/log and the source tree remains clean 2562during the whole build process. 2563 2564 2565See also "U-Boot Porting Guide" below. 2566 2567 2568Monitor Commands - Overview: 2569============================ 2570 2571go - start application at address 'addr' 2572run - run commands in an environment variable 2573bootm - boot application image from memory 2574bootp - boot image via network using BootP/TFTP protocol 2575tftpboot- boot image via network using TFTP protocol 2576 and env variables "ipaddr" and "serverip" 2577 (and eventually "gatewayip") 2578rarpboot- boot image via network using RARP/TFTP protocol 2579diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd' 2580loads - load S-Record file over serial line 2581loadb - load binary file over serial line (kermit mode) 2582md - memory display 2583mm - memory modify (auto-incrementing) 2584nm - memory modify (constant address) 2585mw - memory write (fill) 2586cp - memory copy 2587cmp - memory compare 2588crc32 - checksum calculation 2589imd - i2c memory display 2590imm - i2c memory modify (auto-incrementing) 2591inm - i2c memory modify (constant address) 2592imw - i2c memory write (fill) 2593icrc32 - i2c checksum calculation 2594iprobe - probe to discover valid I2C chip addresses 2595iloop - infinite loop on address range 2596isdram - print SDRAM configuration information 2597sspi - SPI utility commands 2598base - print or set address offset 2599printenv- print environment variables 2600setenv - set environment variables 2601saveenv - save environment variables to persistent storage 2602protect - enable or disable FLASH write protection 2603erase - erase FLASH memory 2604flinfo - print FLASH memory information 2605bdinfo - print Board Info structure 2606iminfo - print header information for application image 2607coninfo - print console devices and informations 2608ide - IDE sub-system 2609loop - infinite loop on address range 2610loopw - infinite write loop on address range 2611mtest - simple RAM test 2612icache - enable or disable instruction cache 2613dcache - enable or disable data cache 2614reset - Perform RESET of the CPU 2615echo - echo args to console 2616version - print monitor version 2617help - print online help 2618? - alias for 'help' 2619 2620 2621Monitor Commands - Detailed Description: 2622======================================== 2623 2624TODO. 2625 2626For now: just type "help <command>". 2627 2628 2629Environment Variables: 2630====================== 2631 2632U-Boot supports user configuration using Environment Variables which 2633can be made persistent by saving to Flash memory. 2634 2635Environment Variables are set using "setenv", printed using 2636"printenv", and saved to Flash using "saveenv". Using "setenv" 2637without a value can be used to delete a variable from the 2638environment. As long as you don't save the environment you are 2639working with an in-memory copy. In case the Flash area containing the 2640environment is erased by accident, a default environment is provided. 2641 2642Some configuration options can be set using Environment Variables: 2643 2644 baudrate - see CONFIG_BAUDRATE 2645 2646 bootdelay - see CONFIG_BOOTDELAY 2647 2648 bootcmd - see CONFIG_BOOTCOMMAND 2649 2650 bootargs - Boot arguments when booting an RTOS image 2651 2652 bootfile - Name of the image to load with TFTP 2653 2654 autoload - if set to "no" (any string beginning with 'n'), 2655 "bootp" will just load perform a lookup of the 2656 configuration from the BOOTP server, but not try to 2657 load any image using TFTP 2658 2659 autostart - if set to "yes", an image loaded using the "bootp", 2660 "rarpboot", "tftpboot" or "diskboot" commands will 2661 be automatically started (by internally calling 2662 "bootm") 2663 2664 If set to "no", a standalone image passed to the 2665 "bootm" command will be copied to the load address 2666 (and eventually uncompressed), but NOT be started. 2667 This can be used to load and uncompress arbitrary 2668 data. 2669 2670 i2cfast - (PPC405GP|PPC405EP only) 2671 if set to 'y' configures Linux I2C driver for fast 2672 mode (400kHZ). This environment variable is used in 2673 initialization code. So, for changes to be effective 2674 it must be saved and board must be reset. 2675 2676 initrd_high - restrict positioning of initrd images: 2677 If this variable is not set, initrd images will be 2678 copied to the highest possible address in RAM; this 2679 is usually what you want since it allows for 2680 maximum initrd size. If for some reason you want to 2681 make sure that the initrd image is loaded below the 2682 CFG_BOOTMAPSZ limit, you can set this environment 2683 variable to a value of "no" or "off" or "0". 2684 Alternatively, you can set it to a maximum upper 2685 address to use (U-Boot will still check that it 2686 does not overwrite the U-Boot stack and data). 2687 2688 For instance, when you have a system with 16 MB 2689 RAM, and want to reserve 4 MB from use by Linux, 2690 you can do this by adding "mem=12M" to the value of 2691 the "bootargs" variable. However, now you must make 2692 sure that the initrd image is placed in the first 2693 12 MB as well - this can be done with 2694 2695 setenv initrd_high 00c00000 2696 2697 If you set initrd_high to 0xFFFFFFFF, this is an 2698 indication to U-Boot that all addresses are legal 2699 for the Linux kernel, including addresses in flash 2700 memory. In this case U-Boot will NOT COPY the 2701 ramdisk at all. This may be useful to reduce the 2702 boot time on your system, but requires that this 2703 feature is supported by your Linux kernel. 2704 2705 ipaddr - IP address; needed for tftpboot command 2706 2707 loadaddr - Default load address for commands like "bootp", 2708 "rarpboot", "tftpboot", "loadb" or "diskboot" 2709 2710 loads_echo - see CONFIG_LOADS_ECHO 2711 2712 serverip - TFTP server IP address; needed for tftpboot command 2713 2714 bootretry - see CONFIG_BOOT_RETRY_TIME 2715 2716 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR 2717 2718 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR 2719 2720 ethprime - When CONFIG_NET_MULTI is enabled controls which 2721 interface is used first. 2722 2723 ethact - When CONFIG_NET_MULTI is enabled controls which 2724 interface is currently active. For example you 2725 can do the following 2726 2727 => setenv ethact FEC ETHERNET 2728 => ping 192.168.0.1 # traffic sent on FEC ETHERNET 2729 => setenv ethact SCC ETHERNET 2730 => ping 10.0.0.1 # traffic sent on SCC ETHERNET 2731 2732 ethrotate - When set to "no" U-Boot does not go through all 2733 available network interfaces. 2734 It just stays at the currently selected interface. 2735 2736 netretry - When set to "no" each network operation will 2737 either succeed or fail without retrying. 2738 When set to "once" the network operation will 2739 fail when all the available network interfaces 2740 are tried once without success. 2741 Useful on scripts which control the retry operation 2742 themselves. 2743 2744 npe_ucode - see CONFIG_IXP4XX_NPE_EXT_UCOD 2745 if set load address for the npe microcode 2746 2747 tftpsrcport - If this is set, the value is used for TFTP's 2748 UDP source port. 2749 2750 tftpdstport - If this is set, the value is used for TFTP's UDP 2751 destination port instead of the Well Know Port 69. 2752 2753 vlan - When set to a value < 4095 the traffic over 2754 ethernet is encapsulated/received over 802.1q 2755 VLAN tagged frames. 2756 2757The following environment variables may be used and automatically 2758updated by the network boot commands ("bootp" and "rarpboot"), 2759depending the information provided by your boot server: 2760 2761 bootfile - see above 2762 dnsip - IP address of your Domain Name Server 2763 dnsip2 - IP address of your secondary Domain Name Server 2764 gatewayip - IP address of the Gateway (Router) to use 2765 hostname - Target hostname 2766 ipaddr - see above 2767 netmask - Subnet Mask 2768 rootpath - Pathname of the root filesystem on the NFS server 2769 serverip - see above 2770 2771 2772There are two special Environment Variables: 2773 2774 serial# - contains hardware identification information such 2775 as type string and/or serial number 2776 ethaddr - Ethernet address 2777 2778These variables can be set only once (usually during manufacturing of 2779the board). U-Boot refuses to delete or overwrite these variables 2780once they have been set once. 2781 2782 2783Further special Environment Variables: 2784 2785 ver - Contains the U-Boot version string as printed 2786 with the "version" command. This variable is 2787 readonly (see CONFIG_VERSION_VARIABLE). 2788 2789 2790Please note that changes to some configuration parameters may take 2791only effect after the next boot (yes, that's just like Windoze :-). 2792 2793 2794Command Line Parsing: 2795===================== 2796 2797There are two different command line parsers available with U-Boot: 2798the old "simple" one, and the much more powerful "hush" shell: 2799 2800Old, simple command line parser: 2801-------------------------------- 2802 2803- supports environment variables (through setenv / saveenv commands) 2804- several commands on one line, separated by ';' 2805- variable substitution using "... ${name} ..." syntax 2806- special characters ('$', ';') can be escaped by prefixing with '\', 2807 for example: 2808 setenv bootcmd bootm \${address} 2809- You can also escape text by enclosing in single apostrophes, for example: 2810 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off' 2811 2812Hush shell: 2813----------- 2814 2815- similar to Bourne shell, with control structures like 2816 if...then...else...fi, for...do...done; while...do...done, 2817 until...do...done, ... 2818- supports environment ("global") variables (through setenv / saveenv 2819 commands) and local shell variables (through standard shell syntax 2820 "name=value"); only environment variables can be used with "run" 2821 command 2822 2823General rules: 2824-------------- 2825 2826(1) If a command line (or an environment variable executed by a "run" 2827 command) contains several commands separated by semicolon, and 2828 one of these commands fails, then the remaining commands will be 2829 executed anyway. 2830 2831(2) If you execute several variables with one call to run (i. e. 2832 calling run with a list af variables as arguments), any failing 2833 command will cause "run" to terminate, i. e. the remaining 2834 variables are not executed. 2835 2836Note for Redundant Ethernet Interfaces: 2837======================================= 2838 2839Some boards come with redundant ethernet interfaces; U-Boot supports 2840such configurations and is capable of automatic selection of a 2841"working" interface when needed. MAC assignment works as follows: 2842 2843Network interfaces are numbered eth0, eth1, eth2, ... Corresponding 2844MAC addresses can be stored in the environment as "ethaddr" (=>eth0), 2845"eth1addr" (=>eth1), "eth2addr", ... 2846 2847If the network interface stores some valid MAC address (for instance 2848in SROM), this is used as default address if there is NO correspon- 2849ding setting in the environment; if the corresponding environment 2850variable is set, this overrides the settings in the card; that means: 2851 2852o If the SROM has a valid MAC address, and there is no address in the 2853 environment, the SROM's address is used. 2854 2855o If there is no valid address in the SROM, and a definition in the 2856 environment exists, then the value from the environment variable is 2857 used. 2858 2859o If both the SROM and the environment contain a MAC address, and 2860 both addresses are the same, this MAC address is used. 2861 2862o If both the SROM and the environment contain a MAC address, and the 2863 addresses differ, the value from the environment is used and a 2864 warning is printed. 2865 2866o If neither SROM nor the environment contain a MAC address, an error 2867 is raised. 2868 2869 2870Image Formats: 2871============== 2872 2873The "boot" commands of this monitor operate on "image" files which 2874can be basicly anything, preceeded by a special header; see the 2875definitions in include/image.h for details; basicly, the header 2876defines the following image properties: 2877 2878* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD, 2879 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks, 2880 LynxOS, pSOS, QNX, RTEMS, ARTOS; 2881 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, ARTOS, LynxOS). 2882* Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86, 2883 IA64, MIPS, NIOS, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit; 2884 Currently supported: ARM, AVR32, Intel x86, MIPS, NIOS, PowerPC). 2885* Compression Type (uncompressed, gzip, bzip2) 2886* Load Address 2887* Entry Point 2888* Image Name 2889* Image Timestamp 2890 2891The header is marked by a special Magic Number, and both the header 2892and the data portions of the image are secured against corruption by 2893CRC32 checksums. 2894 2895 2896Linux Support: 2897============== 2898 2899Although U-Boot should support any OS or standalone application 2900easily, the main focus has always been on Linux during the design of 2901U-Boot. 2902 2903U-Boot includes many features that so far have been part of some 2904special "boot loader" code within the Linux kernel. Also, any 2905"initrd" images to be used are no longer part of one big Linux image; 2906instead, kernel and "initrd" are separate images. This implementation 2907serves several purposes: 2908 2909- the same features can be used for other OS or standalone 2910 applications (for instance: using compressed images to reduce the 2911 Flash memory footprint) 2912 2913- it becomes much easier to port new Linux kernel versions because 2914 lots of low-level, hardware dependent stuff are done by U-Boot 2915 2916- the same Linux kernel image can now be used with different "initrd" 2917 images; of course this also means that different kernel images can 2918 be run with the same "initrd". This makes testing easier (you don't 2919 have to build a new "zImage.initrd" Linux image when you just 2920 change a file in your "initrd"). Also, a field-upgrade of the 2921 software is easier now. 2922 2923 2924Linux HOWTO: 2925============ 2926 2927Porting Linux to U-Boot based systems: 2928--------------------------------------- 2929 2930U-Boot cannot save you from doing all the necessary modifications to 2931configure the Linux device drivers for use with your target hardware 2932(no, we don't intend to provide a full virtual machine interface to 2933Linux :-). 2934 2935But now you can ignore ALL boot loader code (in arch/ppc/mbxboot). 2936 2937Just make sure your machine specific header file (for instance 2938include/asm-ppc/tqm8xx.h) includes the same definition of the Board 2939Information structure as we define in include/u-boot.h, and make 2940sure that your definition of IMAP_ADDR uses the same value as your 2941U-Boot configuration in CFG_IMMR. 2942 2943 2944Configuring the Linux kernel: 2945----------------------------- 2946 2947No specific requirements for U-Boot. Make sure you have some root 2948device (initial ramdisk, NFS) for your target system. 2949 2950 2951Building a Linux Image: 2952----------------------- 2953 2954With U-Boot, "normal" build targets like "zImage" or "bzImage" are 2955not used. If you use recent kernel source, a new build target 2956"uImage" will exist which automatically builds an image usable by 2957U-Boot. Most older kernels also have support for a "pImage" target, 2958which was introduced for our predecessor project PPCBoot and uses a 2959100% compatible format. 2960 2961Example: 2962 2963 make TQM850L_config 2964 make oldconfig 2965 make dep 2966 make uImage 2967 2968The "uImage" build target uses a special tool (in 'tools/mkimage') to 2969encapsulate a compressed Linux kernel image with header information, 2970CRC32 checksum etc. for use with U-Boot. This is what we are doing: 2971 2972* build a standard "vmlinux" kernel image (in ELF binary format): 2973 2974* convert the kernel into a raw binary image: 2975 2976 ${CROSS_COMPILE}-objcopy -O binary \ 2977 -R .note -R .comment \ 2978 -S vmlinux linux.bin 2979 2980* compress the binary image: 2981 2982 gzip -9 linux.bin 2983 2984* package compressed binary image for U-Boot: 2985 2986 mkimage -A ppc -O linux -T kernel -C gzip \ 2987 -a 0 -e 0 -n "Linux Kernel Image" \ 2988 -d linux.bin.gz uImage 2989 2990 2991The "mkimage" tool can also be used to create ramdisk images for use 2992with U-Boot, either separated from the Linux kernel image, or 2993combined into one file. "mkimage" encapsulates the images with a 64 2994byte header containing information about target architecture, 2995operating system, image type, compression method, entry points, time 2996stamp, CRC32 checksums, etc. 2997 2998"mkimage" can be called in two ways: to verify existing images and 2999print the header information, or to build new images. 3000 3001In the first form (with "-l" option) mkimage lists the information 3002contained in the header of an existing U-Boot image; this includes 3003checksum verification: 3004 3005 tools/mkimage -l image 3006 -l ==> list image header information 3007 3008The second form (with "-d" option) is used to build a U-Boot image 3009from a "data file" which is used as image payload: 3010 3011 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \ 3012 -n name -d data_file image 3013 -A ==> set architecture to 'arch' 3014 -O ==> set operating system to 'os' 3015 -T ==> set image type to 'type' 3016 -C ==> set compression type 'comp' 3017 -a ==> set load address to 'addr' (hex) 3018 -e ==> set entry point to 'ep' (hex) 3019 -n ==> set image name to 'name' 3020 -d ==> use image data from 'datafile' 3021 3022Right now, all Linux kernels for PowerPC systems use the same load 3023address (0x00000000), but the entry point address depends on the 3024kernel version: 3025 3026- 2.2.x kernels have the entry point at 0x0000000C, 3027- 2.3.x and later kernels have the entry point at 0x00000000. 3028 3029So a typical call to build a U-Boot image would read: 3030 3031 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 3032 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \ 3033 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz \ 3034 > examples/uImage.TQM850L 3035 Image Name: 2.4.4 kernel for TQM850L 3036 Created: Wed Jul 19 02:34:59 2000 3037 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3038 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 3039 Load Address: 0x00000000 3040 Entry Point: 0x00000000 3041 3042To verify the contents of the image (or check for corruption): 3043 3044 -> tools/mkimage -l examples/uImage.TQM850L 3045 Image Name: 2.4.4 kernel for TQM850L 3046 Created: Wed Jul 19 02:34:59 2000 3047 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3048 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 3049 Load Address: 0x00000000 3050 Entry Point: 0x00000000 3051 3052NOTE: for embedded systems where boot time is critical you can trade 3053speed for memory and install an UNCOMPRESSED image instead: this 3054needs more space in Flash, but boots much faster since it does not 3055need to be uncompressed: 3056 3057 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz 3058 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 3059 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \ 3060 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux \ 3061 > examples/uImage.TQM850L-uncompressed 3062 Image Name: 2.4.4 kernel for TQM850L 3063 Created: Wed Jul 19 02:34:59 2000 3064 Image Type: PowerPC Linux Kernel Image (uncompressed) 3065 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB 3066 Load Address: 0x00000000 3067 Entry Point: 0x00000000 3068 3069 3070Similar you can build U-Boot images from a 'ramdisk.image.gz' file 3071when your kernel is intended to use an initial ramdisk: 3072 3073 -> tools/mkimage -n 'Simple Ramdisk Image' \ 3074 > -A ppc -O linux -T ramdisk -C gzip \ 3075 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd 3076 Image Name: Simple Ramdisk Image 3077 Created: Wed Jan 12 14:01:50 2000 3078 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 3079 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB 3080 Load Address: 0x00000000 3081 Entry Point: 0x00000000 3082 3083 3084Installing a Linux Image: 3085------------------------- 3086 3087To downloading a U-Boot image over the serial (console) interface, 3088you must convert the image to S-Record format: 3089 3090 objcopy -I binary -O srec examples/image examples/image.srec 3091 3092The 'objcopy' does not understand the information in the U-Boot 3093image header, so the resulting S-Record file will be relative to 3094address 0x00000000. To load it to a given address, you need to 3095specify the target address as 'offset' parameter with the 'loads' 3096command. 3097 3098Example: install the image to address 0x40100000 (which on the 3099TQM8xxL is in the first Flash bank): 3100 3101 => erase 40100000 401FFFFF 3102 3103 .......... done 3104 Erased 8 sectors 3105 3106 => loads 40100000 3107 ## Ready for S-Record download ... 3108 ~>examples/image.srec 3109 1 2 3 4 5 6 7 8 9 10 11 12 13 ... 3110 ... 3111 15989 15990 15991 15992 3112 [file transfer complete] 3113 [connected] 3114 ## Start Addr = 0x00000000 3115 3116 3117You can check the success of the download using the 'iminfo' command; 3118this includes a checksum verification so you can be sure no data 3119corruption happened: 3120 3121 => imi 40100000 3122 3123 ## Checking Image at 40100000 ... 3124 Image Name: 2.2.13 for initrd on TQM850L 3125 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3126 Data Size: 335725 Bytes = 327 kB = 0 MB 3127 Load Address: 00000000 3128 Entry Point: 0000000c 3129 Verifying Checksum ... OK 3130 3131 3132Boot Linux: 3133----------- 3134 3135The "bootm" command is used to boot an application that is stored in 3136memory (RAM or Flash). In case of a Linux kernel image, the contents 3137of the "bootargs" environment variable is passed to the kernel as 3138parameters. You can check and modify this variable using the 3139"printenv" and "setenv" commands: 3140 3141 3142 => printenv bootargs 3143 bootargs=root=/dev/ram 3144 3145 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 3146 3147 => printenv bootargs 3148 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 3149 3150 => bootm 40020000 3151 ## Booting Linux kernel at 40020000 ... 3152 Image Name: 2.2.13 for NFS on TQM850L 3153 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3154 Data Size: 381681 Bytes = 372 kB = 0 MB 3155 Load Address: 00000000 3156 Entry Point: 0000000c 3157 Verifying Checksum ... OK 3158 Uncompressing Kernel Image ... OK 3159 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 3160 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 3161 time_init: decrementer frequency = 187500000/60 3162 Calibrating delay loop... 49.77 BogoMIPS 3163 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000] 3164 ... 3165 3166If you want to boot a Linux kernel with initial ram disk, you pass 3167the memory addresses of both the kernel and the initrd image (PPBCOOT 3168format!) to the "bootm" command: 3169 3170 => imi 40100000 40200000 3171 3172 ## Checking Image at 40100000 ... 3173 Image Name: 2.2.13 for initrd on TQM850L 3174 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3175 Data Size: 335725 Bytes = 327 kB = 0 MB 3176 Load Address: 00000000 3177 Entry Point: 0000000c 3178 Verifying Checksum ... OK 3179 3180 ## Checking Image at 40200000 ... 3181 Image Name: Simple Ramdisk Image 3182 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 3183 Data Size: 566530 Bytes = 553 kB = 0 MB 3184 Load Address: 00000000 3185 Entry Point: 00000000 3186 Verifying Checksum ... OK 3187 3188 => bootm 40100000 40200000 3189 ## Booting Linux kernel at 40100000 ... 3190 Image Name: 2.2.13 for initrd on TQM850L 3191 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3192 Data Size: 335725 Bytes = 327 kB = 0 MB 3193 Load Address: 00000000 3194 Entry Point: 0000000c 3195 Verifying Checksum ... OK 3196 Uncompressing Kernel Image ... OK 3197 ## Loading RAMDisk Image at 40200000 ... 3198 Image Name: Simple Ramdisk Image 3199 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 3200 Data Size: 566530 Bytes = 553 kB = 0 MB 3201 Load Address: 00000000 3202 Entry Point: 00000000 3203 Verifying Checksum ... OK 3204 Loading Ramdisk ... OK 3205 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 3206 Boot arguments: root=/dev/ram 3207 time_init: decrementer frequency = 187500000/60 3208 Calibrating delay loop... 49.77 BogoMIPS 3209 ... 3210 RAMDISK: Compressed image found at block 0 3211 VFS: Mounted root (ext2 filesystem). 3212 3213 bash# 3214 3215Boot Linux and pass a flat device tree: 3216----------- 3217 3218First, U-Boot must be compiled with the appropriate defines. See the section 3219titled "Linux Kernel Interface" above for a more in depth explanation. The 3220following is an example of how to start a kernel and pass an updated 3221flat device tree: 3222 3223=> print oftaddr 3224oftaddr=0x300000 3225=> print oft 3226oft=oftrees/mpc8540ads.dtb 3227=> tftp $oftaddr $oft 3228Speed: 1000, full duplex 3229Using TSEC0 device 3230TFTP from server 192.168.1.1; our IP address is 192.168.1.101 3231Filename 'oftrees/mpc8540ads.dtb'. 3232Load address: 0x300000 3233Loading: # 3234done 3235Bytes transferred = 4106 (100a hex) 3236=> tftp $loadaddr $bootfile 3237Speed: 1000, full duplex 3238Using TSEC0 device 3239TFTP from server 192.168.1.1; our IP address is 192.168.1.2 3240Filename 'uImage'. 3241Load address: 0x200000 3242Loading:############ 3243done 3244Bytes transferred = 1029407 (fb51f hex) 3245=> print loadaddr 3246loadaddr=200000 3247=> print oftaddr 3248oftaddr=0x300000 3249=> bootm $loadaddr - $oftaddr 3250## Booting image at 00200000 ... 3251 Image Name: Linux-2.6.17-dirty 3252 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3253 Data Size: 1029343 Bytes = 1005.2 kB 3254 Load Address: 00000000 3255 Entry Point: 00000000 3256 Verifying Checksum ... OK 3257 Uncompressing Kernel Image ... OK 3258Booting using flat device tree at 0x300000 3259Using MPC85xx ADS machine description 3260Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb 3261[snip] 3262 3263 3264More About U-Boot Image Types: 3265------------------------------ 3266 3267U-Boot supports the following image types: 3268 3269 "Standalone Programs" are directly runnable in the environment 3270 provided by U-Boot; it is expected that (if they behave 3271 well) you can continue to work in U-Boot after return from 3272 the Standalone Program. 3273 "OS Kernel Images" are usually images of some Embedded OS which 3274 will take over control completely. Usually these programs 3275 will install their own set of exception handlers, device 3276 drivers, set up the MMU, etc. - this means, that you cannot 3277 expect to re-enter U-Boot except by resetting the CPU. 3278 "RAMDisk Images" are more or less just data blocks, and their 3279 parameters (address, size) are passed to an OS kernel that is 3280 being started. 3281 "Multi-File Images" contain several images, typically an OS 3282 (Linux) kernel image and one or more data images like 3283 RAMDisks. This construct is useful for instance when you want 3284 to boot over the network using BOOTP etc., where the boot 3285 server provides just a single image file, but you want to get 3286 for instance an OS kernel and a RAMDisk image. 3287 3288 "Multi-File Images" start with a list of image sizes, each 3289 image size (in bytes) specified by an "uint32_t" in network 3290 byte order. This list is terminated by an "(uint32_t)0". 3291 Immediately after the terminating 0 follow the images, one by 3292 one, all aligned on "uint32_t" boundaries (size rounded up to 3293 a multiple of 4 bytes). 3294 3295 "Firmware Images" are binary images containing firmware (like 3296 U-Boot or FPGA images) which usually will be programmed to 3297 flash memory. 3298 3299 "Script files" are command sequences that will be executed by 3300 U-Boot's command interpreter; this feature is especially 3301 useful when you configure U-Boot to use a real shell (hush) 3302 as command interpreter. 3303 3304 3305Standalone HOWTO: 3306================= 3307 3308One of the features of U-Boot is that you can dynamically load and 3309run "standalone" applications, which can use some resources of 3310U-Boot like console I/O functions or interrupt services. 3311 3312Two simple examples are included with the sources: 3313 3314"Hello World" Demo: 3315------------------- 3316 3317'examples/hello_world.c' contains a small "Hello World" Demo 3318application; it is automatically compiled when you build U-Boot. 3319It's configured to run at address 0x00040004, so you can play with it 3320like that: 3321 3322 => loads 3323 ## Ready for S-Record download ... 3324 ~>examples/hello_world.srec 3325 1 2 3 4 5 6 7 8 9 10 11 ... 3326 [file transfer complete] 3327 [connected] 3328 ## Start Addr = 0x00040004 3329 3330 => go 40004 Hello World! This is a test. 3331 ## Starting application at 0x00040004 ... 3332 Hello World 3333 argc = 7 3334 argv[0] = "40004" 3335 argv[1] = "Hello" 3336 argv[2] = "World!" 3337 argv[3] = "This" 3338 argv[4] = "is" 3339 argv[5] = "a" 3340 argv[6] = "test." 3341 argv[7] = "<NULL>" 3342 Hit any key to exit ... 3343 3344 ## Application terminated, rc = 0x0 3345 3346Another example, which demonstrates how to register a CPM interrupt 3347handler with the U-Boot code, can be found in 'examples/timer.c'. 3348Here, a CPM timer is set up to generate an interrupt every second. 3349The interrupt service routine is trivial, just printing a '.' 3350character, but this is just a demo program. The application can be 3351controlled by the following keys: 3352 3353 ? - print current values og the CPM Timer registers 3354 b - enable interrupts and start timer 3355 e - stop timer and disable interrupts 3356 q - quit application 3357 3358 => loads 3359 ## Ready for S-Record download ... 3360 ~>examples/timer.srec 3361 1 2 3 4 5 6 7 8 9 10 11 ... 3362 [file transfer complete] 3363 [connected] 3364 ## Start Addr = 0x00040004 3365 3366 => go 40004 3367 ## Starting application at 0x00040004 ... 3368 TIMERS=0xfff00980 3369 Using timer 1 3370 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0 3371 3372Hit 'b': 3373 [q, b, e, ?] Set interval 1000000 us 3374 Enabling timer 3375Hit '?': 3376 [q, b, e, ?] ........ 3377 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0 3378Hit '?': 3379 [q, b, e, ?] . 3380 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0 3381Hit '?': 3382 [q, b, e, ?] . 3383 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0 3384Hit '?': 3385 [q, b, e, ?] . 3386 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0 3387Hit 'e': 3388 [q, b, e, ?] ...Stopping timer 3389Hit 'q': 3390 [q, b, e, ?] ## Application terminated, rc = 0x0 3391 3392 3393Minicom warning: 3394================ 3395 3396Over time, many people have reported problems when trying to use the 3397"minicom" terminal emulation program for serial download. I (wd) 3398consider minicom to be broken, and recommend not to use it. Under 3399Unix, I recommend to use C-Kermit for general purpose use (and 3400especially for kermit binary protocol download ("loadb" command), and 3401use "cu" for S-Record download ("loads" command). 3402 3403Nevertheless, if you absolutely want to use it try adding this 3404configuration to your "File transfer protocols" section: 3405 3406 Name Program Name U/D FullScr IO-Red. Multi 3407 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N 3408 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N 3409 3410 3411NetBSD Notes: 3412============= 3413 3414Starting at version 0.9.2, U-Boot supports NetBSD both as host 3415(build U-Boot) and target system (boots NetBSD/mpc8xx). 3416 3417Building requires a cross environment; it is known to work on 3418NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also 3419need gmake since the Makefiles are not compatible with BSD make). 3420Note that the cross-powerpc package does not install include files; 3421attempting to build U-Boot will fail because <machine/ansi.h> is 3422missing. This file has to be installed and patched manually: 3423 3424 # cd /usr/pkg/cross/powerpc-netbsd/include 3425 # mkdir powerpc 3426 # ln -s powerpc machine 3427 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h 3428 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST 3429 3430Native builds *don't* work due to incompatibilities between native 3431and U-Boot include files. 3432 3433Booting assumes that (the first part of) the image booted is a 3434stage-2 loader which in turn loads and then invokes the kernel 3435proper. Loader sources will eventually appear in the NetBSD source 3436tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the 3437meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz 3438 3439 3440Implementation Internals: 3441========================= 3442 3443The following is not intended to be a complete description of every 3444implementation detail. However, it should help to understand the 3445inner workings of U-Boot and make it easier to port it to custom 3446hardware. 3447 3448 3449Initial Stack, Global Data: 3450--------------------------- 3451 3452The implementation of U-Boot is complicated by the fact that U-Boot 3453starts running out of ROM (flash memory), usually without access to 3454system RAM (because the memory controller is not initialized yet). 3455This means that we don't have writable Data or BSS segments, and BSS 3456is not initialized as zero. To be able to get a C environment working 3457at all, we have to allocate at least a minimal stack. Implementation 3458options for this are defined and restricted by the CPU used: Some CPU 3459models provide on-chip memory (like the IMMR area on MPC8xx and 3460MPC826x processors), on others (parts of) the data cache can be 3461locked as (mis-) used as memory, etc. 3462 3463 Chris Hallinan posted a good summary of these issues to the 3464 u-boot-users mailing list: 3465 3466 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)? 3467 From: "Chris Hallinan" <clh@net1plus.com> 3468 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET) 3469 ... 3470 3471 Correct me if I'm wrong, folks, but the way I understand it 3472 is this: Using DCACHE as initial RAM for Stack, etc, does not 3473 require any physical RAM backing up the cache. The cleverness 3474 is that the cache is being used as a temporary supply of 3475 necessary storage before the SDRAM controller is setup. It's 3476 beyond the scope of this list to expain the details, but you 3477 can see how this works by studying the cache architecture and 3478 operation in the architecture and processor-specific manuals. 3479 3480 OCM is On Chip Memory, which I believe the 405GP has 4K. It 3481 is another option for the system designer to use as an 3482 initial stack/ram area prior to SDRAM being available. Either 3483 option should work for you. Using CS 4 should be fine if your 3484 board designers haven't used it for something that would 3485 cause you grief during the initial boot! It is frequently not 3486 used. 3487 3488 CFG_INIT_RAM_ADDR should be somewhere that won't interfere 3489 with your processor/board/system design. The default value 3490 you will find in any recent u-boot distribution in 3491 walnut.h should work for you. I'd set it to a value larger 3492 than your SDRAM module. If you have a 64MB SDRAM module, set 3493 it above 400_0000. Just make sure your board has no resources 3494 that are supposed to respond to that address! That code in 3495 start.S has been around a while and should work as is when 3496 you get the config right. 3497 3498 -Chris Hallinan 3499 DS4.COM, Inc. 3500 3501It is essential to remember this, since it has some impact on the C 3502code for the initialization procedures: 3503 3504* Initialized global data (data segment) is read-only. Do not attempt 3505 to write it. 3506 3507* Do not use any unitialized global data (or implicitely initialized 3508 as zero data - BSS segment) at all - this is undefined, initiali- 3509 zation is performed later (when relocating to RAM). 3510 3511* Stack space is very limited. Avoid big data buffers or things like 3512 that. 3513 3514Having only the stack as writable memory limits means we cannot use 3515normal global data to share information beween the code. But it 3516turned out that the implementation of U-Boot can be greatly 3517simplified by making a global data structure (gd_t) available to all 3518functions. We could pass a pointer to this data as argument to _all_ 3519functions, but this would bloat the code. Instead we use a feature of 3520the GCC compiler (Global Register Variables) to share the data: we 3521place a pointer (gd) to the global data into a register which we 3522reserve for this purpose. 3523 3524When choosing a register for such a purpose we are restricted by the 3525relevant (E)ABI specifications for the current architecture, and by 3526GCC's implementation. 3527 3528For PowerPC, the following registers have specific use: 3529 R1: stack pointer 3530 R2: reserved for system use 3531 R3-R4: parameter passing and return values 3532 R5-R10: parameter passing 3533 R13: small data area pointer 3534 R30: GOT pointer 3535 R31: frame pointer 3536 3537 (U-Boot also uses R14 as internal GOT pointer.) 3538 3539 ==> U-Boot will use R2 to hold a pointer to the global data 3540 3541 Note: on PPC, we could use a static initializer (since the 3542 address of the global data structure is known at compile time), 3543 but it turned out that reserving a register results in somewhat 3544 smaller code - although the code savings are not that big (on 3545 average for all boards 752 bytes for the whole U-Boot image, 3546 624 text + 127 data). 3547 3548On Blackfin, the normal C ABI (except for P5) is followed as documented here: 3549 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface 3550 3551 ==> U-Boot will use P5 to hold a pointer to the global data 3552 3553On ARM, the following registers are used: 3554 3555 R0: function argument word/integer result 3556 R1-R3: function argument word 3557 R9: GOT pointer 3558 R10: stack limit (used only if stack checking if enabled) 3559 R11: argument (frame) pointer 3560 R12: temporary workspace 3561 R13: stack pointer 3562 R14: link register 3563 R15: program counter 3564 3565 ==> U-Boot will use R8 to hold a pointer to the global data 3566 3567NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope, 3568or current versions of GCC may "optimize" the code too much. 3569 3570Memory Management: 3571------------------ 3572 3573U-Boot runs in system state and uses physical addresses, i.e. the 3574MMU is not used either for address mapping nor for memory protection. 3575 3576The available memory is mapped to fixed addresses using the memory 3577controller. In this process, a contiguous block is formed for each 3578memory type (Flash, SDRAM, SRAM), even when it consists of several 3579physical memory banks. 3580 3581U-Boot is installed in the first 128 kB of the first Flash bank (on 3582TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After 3583booting and sizing and initializing DRAM, the code relocates itself 3584to the upper end of DRAM. Immediately below the U-Boot code some 3585memory is reserved for use by malloc() [see CFG_MALLOC_LEN 3586configuration setting]. Below that, a structure with global Board 3587Info data is placed, followed by the stack (growing downward). 3588 3589Additionally, some exception handler code is copied to the low 8 kB 3590of DRAM (0x00000000 ... 0x00001FFF). 3591 3592So a typical memory configuration with 16 MB of DRAM could look like 3593this: 3594 3595 0x0000 0000 Exception Vector code 3596 : 3597 0x0000 1FFF 3598 0x0000 2000 Free for Application Use 3599 : 3600 : 3601 3602 : 3603 : 3604 0x00FB FF20 Monitor Stack (Growing downward) 3605 0x00FB FFAC Board Info Data and permanent copy of global data 3606 0x00FC 0000 Malloc Arena 3607 : 3608 0x00FD FFFF 3609 0x00FE 0000 RAM Copy of Monitor Code 3610 ... eventually: LCD or video framebuffer 3611 ... eventually: pRAM (Protected RAM - unchanged by reset) 3612 0x00FF FFFF [End of RAM] 3613 3614 3615System Initialization: 3616---------------------- 3617 3618In the reset configuration, U-Boot starts at the reset entry point 3619(on most PowerPC systens at address 0x00000100). Because of the reset 3620configuration for CS0# this is a mirror of the onboard Flash memory. 3621To be able to re-map memory U-Boot then jumps to its link address. 3622To be able to implement the initialization code in C, a (small!) 3623initial stack is set up in the internal Dual Ported RAM (in case CPUs 3624which provide such a feature like MPC8xx or MPC8260), or in a locked 3625part of the data cache. After that, U-Boot initializes the CPU core, 3626the caches and the SIU. 3627 3628Next, all (potentially) available memory banks are mapped using a 3629preliminary mapping. For example, we put them on 512 MB boundaries 3630(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash 3631on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is 3632programmed for SDRAM access. Using the temporary configuration, a 3633simple memory test is run that determines the size of the SDRAM 3634banks. 3635 3636When there is more than one SDRAM bank, and the banks are of 3637different size, the largest is mapped first. For equal size, the first 3638bank (CS2#) is mapped first. The first mapping is always for address 36390x00000000, with any additional banks following immediately to create 3640contiguous memory starting from 0. 3641 3642Then, the monitor installs itself at the upper end of the SDRAM area 3643and allocates memory for use by malloc() and for the global Board 3644Info data; also, the exception vector code is copied to the low RAM 3645pages, and the final stack is set up. 3646 3647Only after this relocation will you have a "normal" C environment; 3648until that you are restricted in several ways, mostly because you are 3649running from ROM, and because the code will have to be relocated to a 3650new address in RAM. 3651 3652 3653U-Boot Porting Guide: 3654---------------------- 3655 3656[Based on messages by Jerry Van Baren in the U-Boot-Users mailing 3657list, October 2002] 3658 3659 3660int main (int argc, char *argv[]) 3661{ 3662 sighandler_t no_more_time; 3663 3664 signal (SIGALRM, no_more_time); 3665 alarm (PROJECT_DEADLINE - toSec (3 * WEEK)); 3666 3667 if (available_money > available_manpower) { 3668 pay consultant to port U-Boot; 3669 return 0; 3670 } 3671 3672 Download latest U-Boot source; 3673 3674 Subscribe to u-boot-users mailing list; 3675 3676 if (clueless) { 3677 email ("Hi, I am new to U-Boot, how do I get started?"); 3678 } 3679 3680 while (learning) { 3681 Read the README file in the top level directory; 3682 Read http://www.denx.de/twiki/bin/view/DULG/Manual ; 3683 Read the source, Luke; 3684 } 3685 3686 if (available_money > toLocalCurrency ($2500)) { 3687 Buy a BDI2000; 3688 } else { 3689 Add a lot of aggravation and time; 3690 } 3691 3692 Create your own board support subdirectory; 3693 3694 Create your own board config file; 3695 3696 while (!running) { 3697 do { 3698 Add / modify source code; 3699 } until (compiles); 3700 Debug; 3701 if (clueless) 3702 email ("Hi, I am having problems..."); 3703 } 3704 Send patch file to Wolfgang; 3705 3706 return 0; 3707} 3708 3709void no_more_time (int sig) 3710{ 3711 hire_a_guru(); 3712} 3713 3714 3715Coding Standards: 3716----------------- 3717 3718All contributions to U-Boot should conform to the Linux kernel 3719coding style; see the file "Documentation/CodingStyle" and the script 3720"scripts/Lindent" in your Linux kernel source directory. In sources 3721originating from U-Boot a style corresponding to "Lindent -pcs" (adding 3722spaces before parameters to function calls) is actually used. 3723 3724Source files originating from a different project (for example the 3725MTD subsystem) are generally exempt from these guidelines and are not 3726reformated to ease subsequent migration to newer versions of those 3727sources. 3728 3729Please note that U-Boot is implemented in C (and to some small parts in 3730Assembler); no C++ is used, so please do not use C++ style comments (//) 3731in your code. 3732 3733Please also stick to the following formatting rules: 3734- remove any trailing white space 3735- use TAB characters for indentation, not spaces 3736- make sure NOT to use DOS '\r\n' line feeds 3737- do not add more than 2 empty lines to source files 3738- do not add trailing empty lines to source files 3739 3740Submissions which do not conform to the standards may be returned 3741with a request to reformat the changes. 3742 3743 3744Submitting Patches: 3745------------------- 3746 3747Since the number of patches for U-Boot is growing, we need to 3748establish some rules. Submissions which do not conform to these rules 3749may be rejected, even when they contain important and valuable stuff. 3750 3751Patches shall be sent to the u-boot-users mailing list. 3752 3753Please see http://www.denx.de/wiki/UBoot/Patches for details. 3754 3755When you send a patch, please include the following information with 3756it: 3757 3758* For bug fixes: a description of the bug and how your patch fixes 3759 this bug. Please try to include a way of demonstrating that the 3760 patch actually fixes something. 3761 3762* For new features: a description of the feature and your 3763 implementation. 3764 3765* A CHANGELOG entry as plaintext (separate from the patch) 3766 3767* For major contributions, your entry to the CREDITS file 3768 3769* When you add support for a new board, don't forget to add this 3770 board to the MAKEALL script, too. 3771 3772* If your patch adds new configuration options, don't forget to 3773 document these in the README file. 3774 3775* The patch itself. If you are using git (which is *strongly* 3776 recommended) you can easily generate the patch using the 3777 "git-format-patch". If you then use "git-send-email" to send it to 3778 the U-Boot mailing list, you will avoid most of the common problems 3779 with some other mail clients. 3780 3781 If you cannot use git, use "diff -purN OLD NEW". If your version of 3782 diff does not support these options, then get the latest version of 3783 GNU diff. 3784 3785 The current directory when running this command shall be the parent 3786 directory of the U-Boot source tree (i. e. please make sure that 3787 your patch includes sufficient directory information for the 3788 affected files). 3789 3790 We prefer patches as plain text. MIME attachments are discouraged, 3791 and compressed attachments must not be used. 3792 3793* If one logical set of modifications affects or creates several 3794 files, all these changes shall be submitted in a SINGLE patch file. 3795 3796* Changesets that contain different, unrelated modifications shall be 3797 submitted as SEPARATE patches, one patch per changeset. 3798 3799 3800Notes: 3801 3802* Before sending the patch, run the MAKEALL script on your patched 3803 source tree and make sure that no errors or warnings are reported 3804 for any of the boards. 3805 3806* Keep your modifications to the necessary minimum: A patch 3807 containing several unrelated changes or arbitrary reformats will be 3808 returned with a request to re-formatting / split it. 3809 3810* If you modify existing code, make sure that your new code does not 3811 add to the memory footprint of the code ;-) Small is beautiful! 3812 When adding new features, these should compile conditionally only 3813 (using #ifdef), and the resulting code with the new feature 3814 disabled must not need more memory than the old code without your 3815 modification. 3816 3817* Remember that there is a size limit of 40 kB per message on the 3818 u-boot-users mailing list. Bigger patches will be moderated. If 3819 they are reasonable and not bigger than 100 kB, they will be 3820 acknowledged. Even bigger patches should be avoided. 3821