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-built (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 - leon2 Files specific to Gaisler LEON2 SPARC CPU 157 - leon3 Files specific to Gaisler LEON3 SPARC CPU 158 - mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs 159 - mcf5227x Files specific to Freescale ColdFire MCF5227x CPUs 160 - mcf532x Files specific to Freescale ColdFire MCF5329 CPUs 161 - mcf5445x Files specific to Freescale ColdFire MCF5445x CPUs 162 - mcf547x_8x Files specific to Freescale ColdFire MCF547x_8x CPUs 163 - mips Files specific to MIPS CPUs 164 - mpc5xx Files specific to Freescale MPC5xx CPUs 165 - mpc5xxx Files specific to Freescale MPC5xxx CPUs 166 - mpc8xx Files specific to Freescale MPC8xx CPUs 167 - mpc8220 Files specific to Freescale MPC8220 CPUs 168 - mpc824x Files specific to Freescale MPC824x CPUs 169 - mpc8260 Files specific to Freescale MPC8260 CPUs 170 - mpc85xx Files specific to Freescale MPC85xx CPUs 171 - nios Files specific to Altera NIOS CPUs 172 - nios2 Files specific to Altera Nios-II CPUs 173 - ppc4xx Files specific to AMCC PowerPC 4xx CPUs 174 - pxa Files specific to Intel XScale PXA CPUs 175 - s3c44b0 Files specific to Samsung S3C44B0 CPUs 176 - sa1100 Files specific to Intel StrongARM SA1100 CPUs 177- disk Code for disk drive partition handling 178- doc Documentation (don't expect too much) 179- drivers Commonly used device drivers 180- dtt Digital Thermometer and Thermostat drivers 181- examples Example code for standalone applications, etc. 182- include Header Files 183- lib_arm Files generic to ARM architecture 184- lib_avr32 Files generic to AVR32 architecture 185- lib_generic Files generic to all architectures 186- lib_i386 Files generic to i386 architecture 187- lib_m68k Files generic to m68k architecture 188- lib_mips Files generic to MIPS architecture 189- lib_nios Files generic to NIOS architecture 190- lib_ppc Files generic to PowerPC architecture 191- lib_sparc Files generic to SPARC architecture 192- libfdt Library files to support flattened device trees 193- net Networking code 194- post Power On Self Test 195- rtc Real Time Clock drivers 196- tools Tools to build S-Record or U-Boot images, etc. 197 198Software Configuration: 199======================= 200 201Configuration is usually done using C preprocessor defines; the 202rationale behind that is to avoid dead code whenever possible. 203 204There are two classes of configuration variables: 205 206* Configuration _OPTIONS_: 207 These are selectable by the user and have names beginning with 208 "CONFIG_". 209 210* Configuration _SETTINGS_: 211 These depend on the hardware etc. and should not be meddled with if 212 you don't know what you're doing; they have names beginning with 213 "CFG_". 214 215Later we will add a configuration tool - probably similar to or even 216identical to what's used for the Linux kernel. Right now, we have to 217do the configuration by hand, which means creating some symbolic 218links and editing some configuration files. We use the TQM8xxL boards 219as an example here. 220 221 222Selection of Processor Architecture and Board Type: 223--------------------------------------------------- 224 225For all supported boards there are ready-to-use default 226configurations available; just type "make <board_name>_config". 227 228Example: For a TQM823L module type: 229 230 cd u-boot 231 make TQM823L_config 232 233For the Cogent platform, you need to specify the cpu type as well; 234e.g. "make cogent_mpc8xx_config". And also configure the cogent 235directory according to the instructions in cogent/README. 236 237 238Configuration Options: 239---------------------- 240 241Configuration depends on the combination of board and CPU type; all 242such information is kept in a configuration file 243"include/configs/<board_name>.h". 244 245Example: For a TQM823L module, all configuration settings are in 246"include/configs/TQM823L.h". 247 248 249Many of the options are named exactly as the corresponding Linux 250kernel configuration options. The intention is to make it easier to 251build a config tool - later. 252 253 254The following options need to be configured: 255 256- CPU Type: Define exactly one, e.g. CONFIG_MPC85XX. 257 258- Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS. 259 260- CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined) 261 Define exactly one, e.g. CONFIG_ATSTK1002 262 263- CPU Module Type: (if CONFIG_COGENT is defined) 264 Define exactly one of 265 CONFIG_CMA286_60_OLD 266--- FIXME --- not tested yet: 267 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P, 268 CONFIG_CMA287_23, CONFIG_CMA287_50 269 270- Motherboard Type: (if CONFIG_COGENT is defined) 271 Define exactly one of 272 CONFIG_CMA101, CONFIG_CMA102 273 274- Motherboard I/O Modules: (if CONFIG_COGENT is defined) 275 Define one or more of 276 CONFIG_CMA302 277 278- Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined) 279 Define one or more of 280 CONFIG_LCD_HEARTBEAT - update a character position on 281 the lcd display every second with 282 a "rotator" |\-/|\-/ 283 284- Board flavour: (if CONFIG_MPC8260ADS is defined) 285 CONFIG_ADSTYPE 286 Possible values are: 287 CFG_8260ADS - original MPC8260ADS 288 CFG_8266ADS - MPC8266ADS 289 CFG_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR 290 CFG_8272ADS - MPC8272ADS 291 292- MPC824X Family Member (if CONFIG_MPC824X is defined) 293 Define exactly one of 294 CONFIG_MPC8240, CONFIG_MPC8245 295 296- 8xx CPU Options: (if using an MPC8xx cpu) 297 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if 298 get_gclk_freq() cannot work 299 e.g. if there is no 32KHz 300 reference PIT/RTC clock 301 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK 302 or XTAL/EXTAL) 303 304- 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU): 305 CFG_8xx_CPUCLK_MIN 306 CFG_8xx_CPUCLK_MAX 307 CONFIG_8xx_CPUCLK_DEFAULT 308 See doc/README.MPC866 309 310 CFG_MEASURE_CPUCLK 311 312 Define this to measure the actual CPU clock instead 313 of relying on the correctness of the configured 314 values. Mostly useful for board bringup to make sure 315 the PLL is locked at the intended frequency. Note 316 that this requires a (stable) reference clock (32 kHz 317 RTC clock or CFG_8XX_XIN) 318 319- Intel Monahans options: 320 CFG_MONAHANS_RUN_MODE_OSC_RATIO 321 322 Defines the Monahans run mode to oscillator 323 ratio. Valid values are 8, 16, 24, 31. The core 324 frequency is this value multiplied by 13 MHz. 325 326 CFG_MONAHANS_TURBO_RUN_MODE_RATIO 327 328 Defines the Monahans turbo mode to oscillator 329 ratio. Valid values are 1 (default if undefined) and 330 2. The core frequency as calculated above is multiplied 331 by this value. 332 333- Linux Kernel Interface: 334 CONFIG_CLOCKS_IN_MHZ 335 336 U-Boot stores all clock information in Hz 337 internally. For binary compatibility with older Linux 338 kernels (which expect the clocks passed in the 339 bd_info data to be in MHz) the environment variable 340 "clocks_in_mhz" can be defined so that U-Boot 341 converts clock data to MHZ before passing it to the 342 Linux kernel. 343 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of 344 "clocks_in_mhz=1" is automatically included in the 345 default environment. 346 347 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only] 348 349 When transfering memsize parameter to linux, some versions 350 expect it to be in bytes, others in MB. 351 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes. 352 353 CONFIG_OF_LIBFDT / CONFIG_OF_FLAT_TREE 354 355 New kernel versions are expecting firmware settings to be 356 passed using flattened device trees (based on open firmware 357 concepts). 358 359 CONFIG_OF_LIBFDT 360 * New libfdt-based support 361 * Adds the "fdt" command 362 * The bootm command automatically updates the fdt 363 364 CONFIG_OF_FLAT_TREE 365 * Deprecated, see CONFIG_OF_LIBFDT 366 * Original ft_build.c-based support 367 * Automatically modifies the dft as part of the bootm command 368 * The environment variable "disable_of", when set, 369 disables this functionality. 370 371 OF_CPU - The proper name of the cpus node. 372 OF_SOC - The proper name of the soc node. 373 OF_TBCLK - The timebase frequency. 374 OF_STDOUT_PATH - The path to the console device 375 376 boards with QUICC Engines require OF_QE to set UCC mac addresses 377 378 CONFIG_OF_BOARD_SETUP 379 380 Board code has addition modification that it wants to make 381 to the flat device tree before handing it off to the kernel 382 383 CONFIG_OF_BOOT_CPU 384 385 This define fills in the correct boot cpu in the boot 386 param header, the default value is zero if undefined. 387 388- Serial Ports: 389 CFG_PL010_SERIAL 390 391 Define this if you want support for Amba PrimeCell PL010 UARTs. 392 393 CFG_PL011_SERIAL 394 395 Define this if you want support for Amba PrimeCell PL011 UARTs. 396 397 CONFIG_PL011_CLOCK 398 399 If you have Amba PrimeCell PL011 UARTs, set this variable to 400 the clock speed of the UARTs. 401 402 CONFIG_PL01x_PORTS 403 404 If you have Amba PrimeCell PL010 or PL011 UARTs on your board, 405 define this to a list of base addresses for each (supported) 406 port. See e.g. include/configs/versatile.h 407 408 409- Console Interface: 410 Depending on board, define exactly one serial port 411 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2, 412 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial 413 console by defining CONFIG_8xx_CONS_NONE 414 415 Note: if CONFIG_8xx_CONS_NONE is defined, the serial 416 port routines must be defined elsewhere 417 (i.e. serial_init(), serial_getc(), ...) 418 419 CONFIG_CFB_CONSOLE 420 Enables console device for a color framebuffer. Needs following 421 defines (cf. smiLynxEM, i8042, board/eltec/bab7xx) 422 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation 423 (default big endian) 424 VIDEO_HW_RECTFILL graphic chip supports 425 rectangle fill 426 (cf. smiLynxEM) 427 VIDEO_HW_BITBLT graphic chip supports 428 bit-blit (cf. smiLynxEM) 429 VIDEO_VISIBLE_COLS visible pixel columns 430 (cols=pitch) 431 VIDEO_VISIBLE_ROWS visible pixel rows 432 VIDEO_PIXEL_SIZE bytes per pixel 433 VIDEO_DATA_FORMAT graphic data format 434 (0-5, cf. cfb_console.c) 435 VIDEO_FB_ADRS framebuffer address 436 VIDEO_KBD_INIT_FCT keyboard int fct 437 (i.e. i8042_kbd_init()) 438 VIDEO_TSTC_FCT test char fct 439 (i.e. i8042_tstc) 440 VIDEO_GETC_FCT get char fct 441 (i.e. i8042_getc) 442 CONFIG_CONSOLE_CURSOR cursor drawing on/off 443 (requires blink timer 444 cf. i8042.c) 445 CFG_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c) 446 CONFIG_CONSOLE_TIME display time/date info in 447 upper right corner 448 (requires CONFIG_CMD_DATE) 449 CONFIG_VIDEO_LOGO display Linux logo in 450 upper left corner 451 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of 452 linux_logo.h for logo. 453 Requires CONFIG_VIDEO_LOGO 454 CONFIG_CONSOLE_EXTRA_INFO 455 addional board info beside 456 the logo 457 458 When CONFIG_CFB_CONSOLE is defined, video console is 459 default i/o. Serial console can be forced with 460 environment 'console=serial'. 461 462 When CONFIG_SILENT_CONSOLE is defined, all console 463 messages (by U-Boot and Linux!) can be silenced with 464 the "silent" environment variable. See 465 doc/README.silent for more information. 466 467- Console Baudrate: 468 CONFIG_BAUDRATE - in bps 469 Select one of the baudrates listed in 470 CFG_BAUDRATE_TABLE, see below. 471 CFG_BRGCLK_PRESCALE, baudrate prescale 472 473- Interrupt driven serial port input: 474 CONFIG_SERIAL_SOFTWARE_FIFO 475 476 PPC405GP only. 477 Use an interrupt handler for receiving data on the 478 serial port. It also enables using hardware handshake 479 (RTS/CTS) and UART's built-in FIFO. Set the number of 480 bytes the interrupt driven input buffer should have. 481 482 Leave undefined to disable this feature, including 483 disable the buffer and hardware handshake. 484 485- Console UART Number: 486 CONFIG_UART1_CONSOLE 487 488 AMCC PPC4xx only. 489 If defined internal UART1 (and not UART0) is used 490 as default U-Boot console. 491 492- Boot Delay: CONFIG_BOOTDELAY - in seconds 493 Delay before automatically booting the default image; 494 set to -1 to disable autoboot. 495 496 See doc/README.autoboot for these options that 497 work with CONFIG_BOOTDELAY. None are required. 498 CONFIG_BOOT_RETRY_TIME 499 CONFIG_BOOT_RETRY_MIN 500 CONFIG_AUTOBOOT_KEYED 501 CONFIG_AUTOBOOT_PROMPT 502 CONFIG_AUTOBOOT_DELAY_STR 503 CONFIG_AUTOBOOT_STOP_STR 504 CONFIG_AUTOBOOT_DELAY_STR2 505 CONFIG_AUTOBOOT_STOP_STR2 506 CONFIG_ZERO_BOOTDELAY_CHECK 507 CONFIG_RESET_TO_RETRY 508 509- Autoboot Command: 510 CONFIG_BOOTCOMMAND 511 Only needed when CONFIG_BOOTDELAY is enabled; 512 define a command string that is automatically executed 513 when no character is read on the console interface 514 within "Boot Delay" after reset. 515 516 CONFIG_BOOTARGS 517 This can be used to pass arguments to the bootm 518 command. The value of CONFIG_BOOTARGS goes into the 519 environment value "bootargs". 520 521 CONFIG_RAMBOOT and CONFIG_NFSBOOT 522 The value of these goes into the environment as 523 "ramboot" and "nfsboot" respectively, and can be used 524 as a convenience, when switching between booting from 525 ram and nfs. 526 527- Pre-Boot Commands: 528 CONFIG_PREBOOT 529 530 When this option is #defined, the existence of the 531 environment variable "preboot" will be checked 532 immediately before starting the CONFIG_BOOTDELAY 533 countdown and/or running the auto-boot command resp. 534 entering interactive mode. 535 536 This feature is especially useful when "preboot" is 537 automatically generated or modified. For an example 538 see the LWMON board specific code: here "preboot" is 539 modified when the user holds down a certain 540 combination of keys on the (special) keyboard when 541 booting the systems 542 543- Serial Download Echo Mode: 544 CONFIG_LOADS_ECHO 545 If defined to 1, all characters received during a 546 serial download (using the "loads" command) are 547 echoed back. This might be needed by some terminal 548 emulations (like "cu"), but may as well just take 549 time on others. This setting #define's the initial 550 value of the "loads_echo" environment variable. 551 552- Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined) 553 CONFIG_KGDB_BAUDRATE 554 Select one of the baudrates listed in 555 CFG_BAUDRATE_TABLE, see below. 556 557- Monitor Functions: 558 Monitor commands can be included or excluded 559 from the build by using the #include files 560 "config_cmd_all.h" and #undef'ing unwanted 561 commands, or using "config_cmd_default.h" 562 and augmenting with additional #define's 563 for wanted commands. 564 565 The default command configuration includes all commands 566 except those marked below with a "*". 567 568 CONFIG_CMD_ASKENV * ask for env variable 569 CONFIG_CMD_AUTOSCRIPT Autoscript Support 570 CONFIG_CMD_BDI bdinfo 571 CONFIG_CMD_BEDBUG * Include BedBug Debugger 572 CONFIG_CMD_BMP * BMP support 573 CONFIG_CMD_BSP * Board specific commands 574 CONFIG_CMD_BOOTD bootd 575 CONFIG_CMD_CACHE * icache, dcache 576 CONFIG_CMD_CONSOLE coninfo 577 CONFIG_CMD_DATE * support for RTC, date/time... 578 CONFIG_CMD_DHCP * DHCP support 579 CONFIG_CMD_DIAG * Diagnostics 580 CONFIG_CMD_DOC * Disk-On-Chip Support 581 CONFIG_CMD_DTT * Digital Therm and Thermostat 582 CONFIG_CMD_ECHO echo arguments 583 CONFIG_CMD_EEPROM * EEPROM read/write support 584 CONFIG_CMD_ELF * bootelf, bootvx 585 CONFIG_CMD_ENV saveenv 586 CONFIG_CMD_FDC * Floppy Disk Support 587 CONFIG_CMD_FAT * FAT partition support 588 CONFIG_CMD_FDOS * Dos diskette Support 589 CONFIG_CMD_FLASH flinfo, erase, protect 590 CONFIG_CMD_FPGA FPGA device initialization support 591 CONFIG_CMD_HWFLOW * RTS/CTS hw flow control 592 CONFIG_CMD_I2C * I2C serial bus support 593 CONFIG_CMD_IDE * IDE harddisk support 594 CONFIG_CMD_IMI iminfo 595 CONFIG_CMD_IMLS List all found images 596 CONFIG_CMD_IMMAP * IMMR dump support 597 CONFIG_CMD_IRQ * irqinfo 598 CONFIG_CMD_ITEST Integer/string test of 2 values 599 CONFIG_CMD_JFFS2 * JFFS2 Support 600 CONFIG_CMD_KGDB * kgdb 601 CONFIG_CMD_LOADB loadb 602 CONFIG_CMD_LOADS loads 603 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base, 604 loop, loopw, mtest 605 CONFIG_CMD_MISC Misc functions like sleep etc 606 CONFIG_CMD_MMC * MMC memory mapped support 607 CONFIG_CMD_MII * MII utility commands 608 CONFIG_CMD_NAND * NAND support 609 CONFIG_CMD_NET bootp, tftpboot, rarpboot 610 CONFIG_CMD_PCI * pciinfo 611 CONFIG_CMD_PCMCIA * PCMCIA support 612 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network 613 host 614 CONFIG_CMD_PORTIO * Port I/O 615 CONFIG_CMD_REGINFO * Register dump 616 CONFIG_CMD_RUN run command in env variable 617 CONFIG_CMD_SAVES * save S record dump 618 CONFIG_CMD_SCSI * SCSI Support 619 CONFIG_CMD_SDRAM * print SDRAM configuration information 620 (requires CONFIG_CMD_I2C) 621 CONFIG_CMD_SETGETDCR Support for DCR Register access 622 (4xx only) 623 CONFIG_CMD_SPI * SPI serial bus support 624 CONFIG_CMD_USB * USB support 625 CONFIG_CMD_VFD * VFD support (TRAB) 626 CONFIG_CMD_BSP * Board SPecific functions 627 CONFIG_CMD_CDP * Cisco Discover Protocol support 628 CONFIG_CMD_FSL * Microblaze FSL support 629 630 631 EXAMPLE: If you want all functions except of network 632 support you can write: 633 634 #include "config_cmd_all.h" 635 #undef CONFIG_CMD_NET 636 637 Other Commands: 638 fdt (flattened device tree) command: CONFIG_OF_LIBFDT 639 640 Note: Don't enable the "icache" and "dcache" commands 641 (configuration option CONFIG_CMD_CACHE) unless you know 642 what you (and your U-Boot users) are doing. Data 643 cache cannot be enabled on systems like the 8xx or 644 8260 (where accesses to the IMMR region must be 645 uncached), and it cannot be disabled on all other 646 systems where we (mis-) use the data cache to hold an 647 initial stack and some data. 648 649 650 XXX - this list needs to get updated! 651 652- Watchdog: 653 CONFIG_WATCHDOG 654 If this variable is defined, it enables watchdog 655 support. There must be support in the platform specific 656 code for a watchdog. For the 8xx and 8260 CPUs, the 657 SIU Watchdog feature is enabled in the SYPCR 658 register. 659 660- U-Boot Version: 661 CONFIG_VERSION_VARIABLE 662 If this variable is defined, an environment variable 663 named "ver" is created by U-Boot showing the U-Boot 664 version as printed by the "version" command. 665 This variable is readonly. 666 667- Real-Time Clock: 668 669 When CONFIG_CMD_DATE is selected, the type of the RTC 670 has to be selected, too. Define exactly one of the 671 following options: 672 673 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx 674 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC 675 CONFIG_RTC_MC13783 - use MC13783 RTC 676 CONFIG_RTC_MC146818 - use MC146818 RTC 677 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC 678 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC 679 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC 680 CONFIG_RTC_DS164x - use Dallas DS164x RTC 681 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC 682 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC 683 CFG_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337 684 685 Note that if the RTC uses I2C, then the I2C interface 686 must also be configured. See I2C Support, below. 687 688- Timestamp Support: 689 690 When CONFIG_TIMESTAMP is selected, the timestamp 691 (date and time) of an image is printed by image 692 commands like bootm or iminfo. This option is 693 automatically enabled when you select CONFIG_CMD_DATE . 694 695- Partition Support: 696 CONFIG_MAC_PARTITION and/or CONFIG_DOS_PARTITION 697 and/or CONFIG_ISO_PARTITION 698 699 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or 700 CONFIG_CMD_SCSI) you must configure support for at 701 least one partition type as well. 702 703- IDE Reset method: 704 CONFIG_IDE_RESET_ROUTINE - this is defined in several 705 board configurations files but used nowhere! 706 707 CONFIG_IDE_RESET - is this is defined, IDE Reset will 708 be performed by calling the function 709 ide_set_reset(int reset) 710 which has to be defined in a board specific file 711 712- ATAPI Support: 713 CONFIG_ATAPI 714 715 Set this to enable ATAPI support. 716 717- LBA48 Support 718 CONFIG_LBA48 719 720 Set this to enable support for disks larger than 137GB 721 Also look at CFG_64BIT_LBA ,CFG_64BIT_VSPRINTF and CFG_64BIT_STRTOUL 722 Whithout these , LBA48 support uses 32bit variables and will 'only' 723 support disks up to 2.1TB. 724 725 CFG_64BIT_LBA: 726 When enabled, makes the IDE subsystem use 64bit sector addresses. 727 Default is 32bit. 728 729- SCSI Support: 730 At the moment only there is only support for the 731 SYM53C8XX SCSI controller; define 732 CONFIG_SCSI_SYM53C8XX to enable it. 733 734 CFG_SCSI_MAX_LUN [8], CFG_SCSI_MAX_SCSI_ID [7] and 735 CFG_SCSI_MAX_DEVICE [CFG_SCSI_MAX_SCSI_ID * 736 CFG_SCSI_MAX_LUN] can be adjusted to define the 737 maximum numbers of LUNs, SCSI ID's and target 738 devices. 739 CFG_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz) 740 741- NETWORK Support (PCI): 742 CONFIG_E1000 743 Support for Intel 8254x gigabit chips. 744 745 CONFIG_E1000_FALLBACK_MAC 746 default MAC for empty eeprom after production. 747 748 CONFIG_EEPRO100 749 Support for Intel 82557/82559/82559ER chips. 750 Optional CONFIG_EEPRO100_SROM_WRITE enables eeprom 751 write routine for first time initialisation. 752 753 CONFIG_TULIP 754 Support for Digital 2114x chips. 755 Optional CONFIG_TULIP_SELECT_MEDIA for board specific 756 modem chip initialisation (KS8761/QS6611). 757 758 CONFIG_NATSEMI 759 Support for National dp83815 chips. 760 761 CONFIG_NS8382X 762 Support for National dp8382[01] gigabit chips. 763 764- NETWORK Support (other): 765 766 CONFIG_DRIVER_LAN91C96 767 Support for SMSC's LAN91C96 chips. 768 769 CONFIG_LAN91C96_BASE 770 Define this to hold the physical address 771 of the LAN91C96's I/O space 772 773 CONFIG_LAN91C96_USE_32_BIT 774 Define this to enable 32 bit addressing 775 776 CONFIG_DRIVER_SMC91111 777 Support for SMSC's LAN91C111 chip 778 779 CONFIG_SMC91111_BASE 780 Define this to hold the physical address 781 of the device (I/O space) 782 783 CONFIG_SMC_USE_32_BIT 784 Define this if data bus is 32 bits 785 786 CONFIG_SMC_USE_IOFUNCS 787 Define this to use i/o functions instead of macros 788 (some hardware wont work with macros) 789 790- USB Support: 791 At the moment only the UHCI host controller is 792 supported (PIP405, MIP405, MPC5200); define 793 CONFIG_USB_UHCI to enable it. 794 define CONFIG_USB_KEYBOARD to enable the USB Keyboard 795 and define CONFIG_USB_STORAGE to enable the USB 796 storage devices. 797 Note: 798 Supported are USB Keyboards and USB Floppy drives 799 (TEAC FD-05PUB). 800 MPC5200 USB requires additional defines: 801 CONFIG_USB_CLOCK 802 for 528 MHz Clock: 0x0001bbbb 803 CONFIG_USB_CONFIG 804 for differential drivers: 0x00001000 805 for single ended drivers: 0x00005000 806 CFG_USB_EVENT_POLL 807 May be defined to allow interrupt polling 808 instead of using asynchronous interrupts 809 810- USB Device: 811 Define the below if you wish to use the USB console. 812 Once firmware is rebuilt from a serial console issue the 813 command "setenv stdin usbtty; setenv stdout usbtty" and 814 attach your usb cable. The Unix command "dmesg" should print 815 it has found a new device. The environment variable usbtty 816 can be set to gserial or cdc_acm to enable your device to 817 appear to a USB host as a Linux gserial device or a 818 Common Device Class Abstract Control Model serial device. 819 If you select usbtty = gserial you should be able to enumerate 820 a Linux host by 821 # modprobe usbserial vendor=0xVendorID product=0xProductID 822 else if using cdc_acm, simply setting the environment 823 variable usbtty to be cdc_acm should suffice. The following 824 might be defined in YourBoardName.h 825 826 CONFIG_USB_DEVICE 827 Define this to build a UDC device 828 829 CONFIG_USB_TTY 830 Define this to have a tty type of device available to 831 talk to the UDC device 832 833 CFG_CONSOLE_IS_IN_ENV 834 Define this if you want stdin, stdout &/or stderr to 835 be set to usbtty. 836 837 mpc8xx: 838 CFG_USB_EXTC_CLK 0xBLAH 839 Derive USB clock from external clock "blah" 840 - CFG_USB_EXTC_CLK 0x02 841 842 CFG_USB_BRG_CLK 0xBLAH 843 Derive USB clock from brgclk 844 - CFG_USB_BRG_CLK 0x04 845 846 If you have a USB-IF assigned VendorID then you may wish to 847 define your own vendor specific values either in BoardName.h 848 or directly in usbd_vendor_info.h. If you don't define 849 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME, 850 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot 851 should pretend to be a Linux device to it's target host. 852 853 CONFIG_USBD_MANUFACTURER 854 Define this string as the name of your company for 855 - CONFIG_USBD_MANUFACTURER "my company" 856 857 CONFIG_USBD_PRODUCT_NAME 858 Define this string as the name of your product 859 - CONFIG_USBD_PRODUCT_NAME "acme usb device" 860 861 CONFIG_USBD_VENDORID 862 Define this as your assigned Vendor ID from the USB 863 Implementors Forum. This *must* be a genuine Vendor ID 864 to avoid polluting the USB namespace. 865 - CONFIG_USBD_VENDORID 0xFFFF 866 867 CONFIG_USBD_PRODUCTID 868 Define this as the unique Product ID 869 for your device 870 - CONFIG_USBD_PRODUCTID 0xFFFF 871 872 873- MMC Support: 874 The MMC controller on the Intel PXA is supported. To 875 enable this define CONFIG_MMC. The MMC can be 876 accessed from the boot prompt by mapping the device 877 to physical memory similar to flash. Command line is 878 enabled with CONFIG_CMD_MMC. The MMC driver also works with 879 the FAT fs. This is enabled with CONFIG_CMD_FAT. 880 881- Journaling Flash filesystem support: 882 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE, 883 CONFIG_JFFS2_NAND_DEV 884 Define these for a default partition on a NAND device 885 886 CFG_JFFS2_FIRST_SECTOR, 887 CFG_JFFS2_FIRST_BANK, CFG_JFFS2_NUM_BANKS 888 Define these for a default partition on a NOR device 889 890 CFG_JFFS_CUSTOM_PART 891 Define this to create an own partition. You have to provide a 892 function struct part_info* jffs2_part_info(int part_num) 893 894 If you define only one JFFS2 partition you may also want to 895 #define CFG_JFFS_SINGLE_PART 1 896 to disable the command chpart. This is the default when you 897 have not defined a custom partition 898 899- Keyboard Support: 900 CONFIG_ISA_KEYBOARD 901 902 Define this to enable standard (PC-Style) keyboard 903 support 904 905 CONFIG_I8042_KBD 906 Standard PC keyboard driver with US (is default) and 907 GERMAN key layout (switch via environment 'keymap=de') support. 908 Export function i8042_kbd_init, i8042_tstc and i8042_getc 909 for cfb_console. Supports cursor blinking. 910 911- Video support: 912 CONFIG_VIDEO 913 914 Define this to enable video support (for output to 915 video). 916 917 CONFIG_VIDEO_CT69000 918 919 Enable Chips & Technologies 69000 Video chip 920 921 CONFIG_VIDEO_SMI_LYNXEM 922 Enable Silicon Motion SMI 712/710/810 Video chip. The 923 video output is selected via environment 'videoout' 924 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is 925 assumed. 926 927 For the CT69000 and SMI_LYNXEM drivers, videomode is 928 selected via environment 'videomode'. Two diferent ways 929 are possible: 930 - "videomode=num" 'num' is a standard LiLo mode numbers. 931 Following standard modes are supported (* is default): 932 933 Colors 640x480 800x600 1024x768 1152x864 1280x1024 934 -------------+--------------------------------------------- 935 8 bits | 0x301* 0x303 0x305 0x161 0x307 936 15 bits | 0x310 0x313 0x316 0x162 0x319 937 16 bits | 0x311 0x314 0x317 0x163 0x31A 938 24 bits | 0x312 0x315 0x318 ? 0x31B 939 -------------+--------------------------------------------- 940 (i.e. setenv videomode 317; saveenv; reset;) 941 942 - "videomode=bootargs" all the video parameters are parsed 943 from the bootargs. (See drivers/video/videomodes.c) 944 945 946 CONFIG_VIDEO_SED13806 947 Enable Epson SED13806 driver. This driver supports 8bpp 948 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP 949 or CONFIG_VIDEO_SED13806_16BPP 950 951- Keyboard Support: 952 CONFIG_KEYBOARD 953 954 Define this to enable a custom keyboard support. 955 This simply calls drv_keyboard_init() which must be 956 defined in your board-specific files. 957 The only board using this so far is RBC823. 958 959- LCD Support: CONFIG_LCD 960 961 Define this to enable LCD support (for output to LCD 962 display); also select one of the supported displays 963 by defining one of these: 964 965 CONFIG_NEC_NL6448AC33: 966 967 NEC NL6448AC33-18. Active, color, single scan. 968 969 CONFIG_NEC_NL6448BC20 970 971 NEC NL6448BC20-08. 6.5", 640x480. 972 Active, color, single scan. 973 974 CONFIG_NEC_NL6448BC33_54 975 976 NEC NL6448BC33-54. 10.4", 640x480. 977 Active, color, single scan. 978 979 CONFIG_SHARP_16x9 980 981 Sharp 320x240. Active, color, single scan. 982 It isn't 16x9, and I am not sure what it is. 983 984 CONFIG_SHARP_LQ64D341 985 986 Sharp LQ64D341 display, 640x480. 987 Active, color, single scan. 988 989 CONFIG_HLD1045 990 991 HLD1045 display, 640x480. 992 Active, color, single scan. 993 994 CONFIG_OPTREX_BW 995 996 Optrex CBL50840-2 NF-FW 99 22 M5 997 or 998 Hitachi LMG6912RPFC-00T 999 or 1000 Hitachi SP14Q002 1001 1002 320x240. Black & white. 1003 1004 Normally display is black on white background; define 1005 CFG_WHITE_ON_BLACK to get it inverted. 1006 1007- Splash Screen Support: CONFIG_SPLASH_SCREEN 1008 1009 If this option is set, the environment is checked for 1010 a variable "splashimage". If found, the usual display 1011 of logo, copyright and system information on the LCD 1012 is suppressed and the BMP image at the address 1013 specified in "splashimage" is loaded instead. The 1014 console is redirected to the "nulldev", too. This 1015 allows for a "silent" boot where a splash screen is 1016 loaded very quickly after power-on. 1017 1018- Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP 1019 1020 If this option is set, additionally to standard BMP 1021 images, gzipped BMP images can be displayed via the 1022 splashscreen support or the bmp command. 1023 1024- Compression support: 1025 CONFIG_BZIP2 1026 1027 If this option is set, support for bzip2 compressed 1028 images is included. If not, only uncompressed and gzip 1029 compressed images are supported. 1030 1031 NOTE: the bzip2 algorithm requires a lot of RAM, so 1032 the malloc area (as defined by CFG_MALLOC_LEN) should 1033 be at least 4MB. 1034 1035- MII/PHY support: 1036 CONFIG_PHY_ADDR 1037 1038 The address of PHY on MII bus. 1039 1040 CONFIG_PHY_CLOCK_FREQ (ppc4xx) 1041 1042 The clock frequency of the MII bus 1043 1044 CONFIG_PHY_GIGE 1045 1046 If this option is set, support for speed/duplex 1047 detection of Gigabit PHY is included. 1048 1049 CONFIG_PHY_RESET_DELAY 1050 1051 Some PHY like Intel LXT971A need extra delay after 1052 reset before any MII register access is possible. 1053 For such PHY, set this option to the usec delay 1054 required. (minimum 300usec for LXT971A) 1055 1056 CONFIG_PHY_CMD_DELAY (ppc4xx) 1057 1058 Some PHY like Intel LXT971A need extra delay after 1059 command issued before MII status register can be read 1060 1061- Ethernet address: 1062 CONFIG_ETHADDR 1063 CONFIG_ETH2ADDR 1064 CONFIG_ETH3ADDR 1065 1066 Define a default value for ethernet address to use 1067 for the respective ethernet interface, in case this 1068 is not determined automatically. 1069 1070- IP address: 1071 CONFIG_IPADDR 1072 1073 Define a default value for the IP address to use for 1074 the default ethernet interface, in case this is not 1075 determined through e.g. bootp. 1076 1077- Server IP address: 1078 CONFIG_SERVERIP 1079 1080 Defines a default value for theIP address of a TFTP 1081 server to contact when using the "tftboot" command. 1082 1083- Multicast TFTP Mode: 1084 CONFIG_MCAST_TFTP 1085 1086 Defines whether you want to support multicast TFTP as per 1087 rfc-2090; for example to work with atftp. Lets lots of targets 1088 tftp down the same boot image concurrently. Note: the ethernet 1089 driver in use must provide a function: mcast() to join/leave a 1090 multicast group. 1091 1092 CONFIG_BOOTP_RANDOM_DELAY 1093- BOOTP Recovery Mode: 1094 CONFIG_BOOTP_RANDOM_DELAY 1095 1096 If you have many targets in a network that try to 1097 boot using BOOTP, you may want to avoid that all 1098 systems send out BOOTP requests at precisely the same 1099 moment (which would happen for instance at recovery 1100 from a power failure, when all systems will try to 1101 boot, thus flooding the BOOTP server. Defining 1102 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be 1103 inserted before sending out BOOTP requests. The 1104 following delays are inserted then: 1105 1106 1st BOOTP request: delay 0 ... 1 sec 1107 2nd BOOTP request: delay 0 ... 2 sec 1108 3rd BOOTP request: delay 0 ... 4 sec 1109 4th and following 1110 BOOTP requests: delay 0 ... 8 sec 1111 1112- DHCP Advanced Options: 1113 You can fine tune the DHCP functionality by defining 1114 CONFIG_BOOTP_* symbols: 1115 1116 CONFIG_BOOTP_SUBNETMASK 1117 CONFIG_BOOTP_GATEWAY 1118 CONFIG_BOOTP_HOSTNAME 1119 CONFIG_BOOTP_NISDOMAIN 1120 CONFIG_BOOTP_BOOTPATH 1121 CONFIG_BOOTP_BOOTFILESIZE 1122 CONFIG_BOOTP_DNS 1123 CONFIG_BOOTP_DNS2 1124 CONFIG_BOOTP_SEND_HOSTNAME 1125 CONFIG_BOOTP_NTPSERVER 1126 CONFIG_BOOTP_TIMEOFFSET 1127 CONFIG_BOOTP_VENDOREX 1128 1129 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip 1130 environment variable, not the BOOTP server. 1131 1132 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS 1133 serverip from a DHCP server, it is possible that more 1134 than one DNS serverip is offered to the client. 1135 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS 1136 serverip will be stored in the additional environment 1137 variable "dnsip2". The first DNS serverip is always 1138 stored in the variable "dnsip", when CONFIG_BOOTP_DNS 1139 is defined. 1140 1141 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable 1142 to do a dynamic update of a DNS server. To do this, they 1143 need the hostname of the DHCP requester. 1144 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content 1145 of the "hostname" environment variable is passed as 1146 option 12 to the DHCP server. 1147 1148 CONFIG_BOOTP_DHCP_REQUEST_DELAY 1149 1150 A 32bit value in microseconds for a delay between 1151 receiving a "DHCP Offer" and sending the "DHCP Request". 1152 This fixes a problem with certain DHCP servers that don't 1153 respond 100% of the time to a "DHCP request". E.g. On an 1154 AT91RM9200 processor running at 180MHz, this delay needed 1155 to be *at least* 15,000 usec before a Windows Server 2003 1156 DHCP server would reply 100% of the time. I recommend at 1157 least 50,000 usec to be safe. The alternative is to hope 1158 that one of the retries will be successful but note that 1159 the DHCP timeout and retry process takes a longer than 1160 this delay. 1161 1162 - CDP Options: 1163 CONFIG_CDP_DEVICE_ID 1164 1165 The device id used in CDP trigger frames. 1166 1167 CONFIG_CDP_DEVICE_ID_PREFIX 1168 1169 A two character string which is prefixed to the MAC address 1170 of the device. 1171 1172 CONFIG_CDP_PORT_ID 1173 1174 A printf format string which contains the ascii name of 1175 the port. Normally is set to "eth%d" which sets 1176 eth0 for the first ethernet, eth1 for the second etc. 1177 1178 CONFIG_CDP_CAPABILITIES 1179 1180 A 32bit integer which indicates the device capabilities; 1181 0x00000010 for a normal host which does not forwards. 1182 1183 CONFIG_CDP_VERSION 1184 1185 An ascii string containing the version of the software. 1186 1187 CONFIG_CDP_PLATFORM 1188 1189 An ascii string containing the name of the platform. 1190 1191 CONFIG_CDP_TRIGGER 1192 1193 A 32bit integer sent on the trigger. 1194 1195 CONFIG_CDP_POWER_CONSUMPTION 1196 1197 A 16bit integer containing the power consumption of the 1198 device in .1 of milliwatts. 1199 1200 CONFIG_CDP_APPLIANCE_VLAN_TYPE 1201 1202 A byte containing the id of the VLAN. 1203 1204- Status LED: CONFIG_STATUS_LED 1205 1206 Several configurations allow to display the current 1207 status using a LED. For instance, the LED will blink 1208 fast while running U-Boot code, stop blinking as 1209 soon as a reply to a BOOTP request was received, and 1210 start blinking slow once the Linux kernel is running 1211 (supported by a status LED driver in the Linux 1212 kernel). Defining CONFIG_STATUS_LED enables this 1213 feature in U-Boot. 1214 1215- CAN Support: CONFIG_CAN_DRIVER 1216 1217 Defining CONFIG_CAN_DRIVER enables CAN driver support 1218 on those systems that support this (optional) 1219 feature, like the TQM8xxL modules. 1220 1221- I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C 1222 1223 These enable I2C serial bus commands. Defining either of 1224 (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will 1225 include the appropriate I2C driver for the selected cpu. 1226 1227 This will allow you to use i2c commands at the u-boot 1228 command line (as long as you set CONFIG_CMD_I2C in 1229 CONFIG_COMMANDS) and communicate with i2c based realtime 1230 clock chips. See common/cmd_i2c.c for a description of the 1231 command line interface. 1232 1233 CONFIG_I2C_CMD_TREE is a recommended option that places 1234 all I2C commands under a single 'i2c' root command. The 1235 older 'imm', 'imd', 'iprobe' etc. commands are considered 1236 deprecated and may disappear in the future. 1237 1238 CONFIG_HARD_I2C selects a hardware I2C controller. 1239 1240 CONFIG_SOFT_I2C configures u-boot to use a software (aka 1241 bit-banging) driver instead of CPM or similar hardware 1242 support for I2C. 1243 1244 There are several other quantities that must also be 1245 defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C. 1246 1247 In both cases you will need to define CFG_I2C_SPEED 1248 to be the frequency (in Hz) at which you wish your i2c bus 1249 to run and CFG_I2C_SLAVE to be the address of this node (ie 1250 the cpu's i2c node address). 1251 1252 Now, the u-boot i2c code for the mpc8xx (cpu/mpc8xx/i2c.c) 1253 sets the cpu up as a master node and so its address should 1254 therefore be cleared to 0 (See, eg, MPC823e User's Manual 1255 p.16-473). So, set CFG_I2C_SLAVE to 0. 1256 1257 That's all that's required for CONFIG_HARD_I2C. 1258 1259 If you use the software i2c interface (CONFIG_SOFT_I2C) 1260 then the following macros need to be defined (examples are 1261 from include/configs/lwmon.h): 1262 1263 I2C_INIT 1264 1265 (Optional). Any commands necessary to enable the I2C 1266 controller or configure ports. 1267 1268 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL) 1269 1270 I2C_PORT 1271 1272 (Only for MPC8260 CPU). The I/O port to use (the code 1273 assumes both bits are on the same port). Valid values 1274 are 0..3 for ports A..D. 1275 1276 I2C_ACTIVE 1277 1278 The code necessary to make the I2C data line active 1279 (driven). If the data line is open collector, this 1280 define can be null. 1281 1282 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA) 1283 1284 I2C_TRISTATE 1285 1286 The code necessary to make the I2C data line tri-stated 1287 (inactive). If the data line is open collector, this 1288 define can be null. 1289 1290 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA) 1291 1292 I2C_READ 1293 1294 Code that returns TRUE if the I2C data line is high, 1295 FALSE if it is low. 1296 1297 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0) 1298 1299 I2C_SDA(bit) 1300 1301 If <bit> is TRUE, sets the I2C data line high. If it 1302 is FALSE, it clears it (low). 1303 1304 eg: #define I2C_SDA(bit) \ 1305 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \ 1306 else immr->im_cpm.cp_pbdat &= ~PB_SDA 1307 1308 I2C_SCL(bit) 1309 1310 If <bit> is TRUE, sets the I2C clock line high. If it 1311 is FALSE, it clears it (low). 1312 1313 eg: #define I2C_SCL(bit) \ 1314 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \ 1315 else immr->im_cpm.cp_pbdat &= ~PB_SCL 1316 1317 I2C_DELAY 1318 1319 This delay is invoked four times per clock cycle so this 1320 controls the rate of data transfer. The data rate thus 1321 is 1 / (I2C_DELAY * 4). Often defined to be something 1322 like: 1323 1324 #define I2C_DELAY udelay(2) 1325 1326 CFG_I2C_INIT_BOARD 1327 1328 When a board is reset during an i2c bus transfer 1329 chips might think that the current transfer is still 1330 in progress. On some boards it is possible to access 1331 the i2c SCLK line directly, either by using the 1332 processor pin as a GPIO or by having a second pin 1333 connected to the bus. If this option is defined a 1334 custom i2c_init_board() routine in boards/xxx/board.c 1335 is run early in the boot sequence. 1336 1337 CONFIG_I2CFAST (PPC405GP|PPC405EP only) 1338 1339 This option enables configuration of bi_iic_fast[] flags 1340 in u-boot bd_info structure based on u-boot environment 1341 variable "i2cfast". (see also i2cfast) 1342 1343 CONFIG_I2C_MULTI_BUS 1344 1345 This option allows the use of multiple I2C buses, each of which 1346 must have a controller. At any point in time, only one bus is 1347 active. To switch to a different bus, use the 'i2c dev' command. 1348 Note that bus numbering is zero-based. 1349 1350 CFG_I2C_NOPROBES 1351 1352 This option specifies a list of I2C devices that will be skipped 1353 when the 'i2c probe' command is issued (or 'iprobe' using the legacy 1354 command). If CONFIG_I2C_MULTI_BUS is set, specify a list of bus-device 1355 pairs. Otherwise, specify a 1D array of device addresses 1356 1357 e.g. 1358 #undef CONFIG_I2C_MULTI_BUS 1359 #define CFG_I2C_NOPROBES {0x50,0x68} 1360 1361 will skip addresses 0x50 and 0x68 on a board with one I2C bus 1362 1363 #define CONFIG_I2C_MULTI_BUS 1364 #define CFG_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}} 1365 1366 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1 1367 1368 CFG_SPD_BUS_NUM 1369 1370 If defined, then this indicates the I2C bus number for DDR SPD. 1371 If not defined, then U-Boot assumes that SPD is on I2C bus 0. 1372 1373 CFG_RTC_BUS_NUM 1374 1375 If defined, then this indicates the I2C bus number for the RTC. 1376 If not defined, then U-Boot assumes that RTC is on I2C bus 0. 1377 1378 CFG_DTT_BUS_NUM 1379 1380 If defined, then this indicates the I2C bus number for the DTT. 1381 If not defined, then U-Boot assumes that DTT is on I2C bus 0. 1382 1383 CONFIG_FSL_I2C 1384 1385 Define this option if you want to use Freescale's I2C driver in 1386 drivers/i2c/fsl_i2c.c. 1387 1388 1389- SPI Support: CONFIG_SPI 1390 1391 Enables SPI driver (so far only tested with 1392 SPI EEPROM, also an instance works with Crystal A/D and 1393 D/As on the SACSng board) 1394 1395 CONFIG_SPI_X 1396 1397 Enables extended (16-bit) SPI EEPROM addressing. 1398 (symmetrical to CONFIG_I2C_X) 1399 1400 CONFIG_SOFT_SPI 1401 1402 Enables a software (bit-bang) SPI driver rather than 1403 using hardware support. This is a general purpose 1404 driver that only requires three general I/O port pins 1405 (two outputs, one input) to function. If this is 1406 defined, the board configuration must define several 1407 SPI configuration items (port pins to use, etc). For 1408 an example, see include/configs/sacsng.h. 1409 1410 CONFIG_HARD_SPI 1411 1412 Enables a hardware SPI driver for general-purpose reads 1413 and writes. As with CONFIG_SOFT_SPI, the board configuration 1414 must define a list of chip-select function pointers. 1415 Currently supported on some MPC8xxx processors. For an 1416 example, see include/configs/mpc8349emds.h. 1417 1418 CONFIG_MXC_SPI 1419 1420 Enables the driver for the SPI controllers on i.MX and MXC 1421 SoCs. Currently only i.MX31 is supported. 1422 1423- FPGA Support: CONFIG_FPGA 1424 1425 Enables FPGA subsystem. 1426 1427 CONFIG_FPGA_<vendor> 1428 1429 Enables support for specific chip vendors. 1430 (ALTERA, XILINX) 1431 1432 CONFIG_FPGA_<family> 1433 1434 Enables support for FPGA family. 1435 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX) 1436 1437 CONFIG_FPGA_COUNT 1438 1439 Specify the number of FPGA devices to support. 1440 1441 CFG_FPGA_PROG_FEEDBACK 1442 1443 Enable printing of hash marks during FPGA configuration. 1444 1445 CFG_FPGA_CHECK_BUSY 1446 1447 Enable checks on FPGA configuration interface busy 1448 status by the configuration function. This option 1449 will require a board or device specific function to 1450 be written. 1451 1452 CONFIG_FPGA_DELAY 1453 1454 If defined, a function that provides delays in the FPGA 1455 configuration driver. 1456 1457 CFG_FPGA_CHECK_CTRLC 1458 Allow Control-C to interrupt FPGA configuration 1459 1460 CFG_FPGA_CHECK_ERROR 1461 1462 Check for configuration errors during FPGA bitfile 1463 loading. For example, abort during Virtex II 1464 configuration if the INIT_B line goes low (which 1465 indicated a CRC error). 1466 1467 CFG_FPGA_WAIT_INIT 1468 1469 Maximum time to wait for the INIT_B line to deassert 1470 after PROB_B has been deasserted during a Virtex II 1471 FPGA configuration sequence. The default time is 500 1472 mS. 1473 1474 CFG_FPGA_WAIT_BUSY 1475 1476 Maximum time to wait for BUSY to deassert during 1477 Virtex II FPGA configuration. The default is 5 mS. 1478 1479 CFG_FPGA_WAIT_CONFIG 1480 1481 Time to wait after FPGA configuration. The default is 1482 200 mS. 1483 1484- Configuration Management: 1485 CONFIG_IDENT_STRING 1486 1487 If defined, this string will be added to the U-Boot 1488 version information (U_BOOT_VERSION) 1489 1490- Vendor Parameter Protection: 1491 1492 U-Boot considers the values of the environment 1493 variables "serial#" (Board Serial Number) and 1494 "ethaddr" (Ethernet Address) to be parameters that 1495 are set once by the board vendor / manufacturer, and 1496 protects these variables from casual modification by 1497 the user. Once set, these variables are read-only, 1498 and write or delete attempts are rejected. You can 1499 change this behviour: 1500 1501 If CONFIG_ENV_OVERWRITE is #defined in your config 1502 file, the write protection for vendor parameters is 1503 completely disabled. Anybody can change or delete 1504 these parameters. 1505 1506 Alternatively, if you #define _both_ CONFIG_ETHADDR 1507 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default 1508 ethernet address is installed in the environment, 1509 which can be changed exactly ONCE by the user. [The 1510 serial# is unaffected by this, i. e. it remains 1511 read-only.] 1512 1513- Protected RAM: 1514 CONFIG_PRAM 1515 1516 Define this variable to enable the reservation of 1517 "protected RAM", i. e. RAM which is not overwritten 1518 by U-Boot. Define CONFIG_PRAM to hold the number of 1519 kB you want to reserve for pRAM. You can overwrite 1520 this default value by defining an environment 1521 variable "pram" to the number of kB you want to 1522 reserve. Note that the board info structure will 1523 still show the full amount of RAM. If pRAM is 1524 reserved, a new environment variable "mem" will 1525 automatically be defined to hold the amount of 1526 remaining RAM in a form that can be passed as boot 1527 argument to Linux, for instance like that: 1528 1529 setenv bootargs ... mem=\${mem} 1530 saveenv 1531 1532 This way you can tell Linux not to use this memory, 1533 either, which results in a memory region that will 1534 not be affected by reboots. 1535 1536 *WARNING* If your board configuration uses automatic 1537 detection of the RAM size, you must make sure that 1538 this memory test is non-destructive. So far, the 1539 following board configurations are known to be 1540 "pRAM-clean": 1541 1542 ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL, 1543 HERMES, IP860, RPXlite, LWMON, LANTEC, 1544 PCU_E, FLAGADM, TQM8260 1545 1546- Error Recovery: 1547 CONFIG_PANIC_HANG 1548 1549 Define this variable to stop the system in case of a 1550 fatal error, so that you have to reset it manually. 1551 This is probably NOT a good idea for an embedded 1552 system where you want to system to reboot 1553 automatically as fast as possible, but it may be 1554 useful during development since you can try to debug 1555 the conditions that lead to the situation. 1556 1557 CONFIG_NET_RETRY_COUNT 1558 1559 This variable defines the number of retries for 1560 network operations like ARP, RARP, TFTP, or BOOTP 1561 before giving up the operation. If not defined, a 1562 default value of 5 is used. 1563 1564- Command Interpreter: 1565 CONFIG_AUTO_COMPLETE 1566 1567 Enable auto completion of commands using TAB. 1568 1569 Note that this feature has NOT been implemented yet 1570 for the "hush" shell. 1571 1572 1573 CFG_HUSH_PARSER 1574 1575 Define this variable to enable the "hush" shell (from 1576 Busybox) as command line interpreter, thus enabling 1577 powerful command line syntax like 1578 if...then...else...fi conditionals or `&&' and '||' 1579 constructs ("shell scripts"). 1580 1581 If undefined, you get the old, much simpler behaviour 1582 with a somewhat smaller memory footprint. 1583 1584 1585 CFG_PROMPT_HUSH_PS2 1586 1587 This defines the secondary prompt string, which is 1588 printed when the command interpreter needs more input 1589 to complete a command. Usually "> ". 1590 1591 Note: 1592 1593 In the current implementation, the local variables 1594 space and global environment variables space are 1595 separated. Local variables are those you define by 1596 simply typing `name=value'. To access a local 1597 variable later on, you have write `$name' or 1598 `${name}'; to execute the contents of a variable 1599 directly type `$name' at the command prompt. 1600 1601 Global environment variables are those you use 1602 setenv/printenv to work with. To run a command stored 1603 in such a variable, you need to use the run command, 1604 and you must not use the '$' sign to access them. 1605 1606 To store commands and special characters in a 1607 variable, please use double quotation marks 1608 surrounding the whole text of the variable, instead 1609 of the backslashes before semicolons and special 1610 symbols. 1611 1612- Commandline Editing and History: 1613 CONFIG_CMDLINE_EDITING 1614 1615 Enable editiong and History functions for interactive 1616 commandline input operations 1617 1618- Default Environment: 1619 CONFIG_EXTRA_ENV_SETTINGS 1620 1621 Define this to contain any number of null terminated 1622 strings (variable = value pairs) that will be part of 1623 the default environment compiled into the boot image. 1624 1625 For example, place something like this in your 1626 board's config file: 1627 1628 #define CONFIG_EXTRA_ENV_SETTINGS \ 1629 "myvar1=value1\0" \ 1630 "myvar2=value2\0" 1631 1632 Warning: This method is based on knowledge about the 1633 internal format how the environment is stored by the 1634 U-Boot code. This is NOT an official, exported 1635 interface! Although it is unlikely that this format 1636 will change soon, there is no guarantee either. 1637 You better know what you are doing here. 1638 1639 Note: overly (ab)use of the default environment is 1640 discouraged. Make sure to check other ways to preset 1641 the environment like the autoscript function or the 1642 boot command first. 1643 1644- DataFlash Support: 1645 CONFIG_HAS_DATAFLASH 1646 1647 Defining this option enables DataFlash features and 1648 allows to read/write in Dataflash via the standard 1649 commands cp, md... 1650 1651- SystemACE Support: 1652 CONFIG_SYSTEMACE 1653 1654 Adding this option adds support for Xilinx SystemACE 1655 chips attached via some sort of local bus. The address 1656 of the chip must alsh be defined in the 1657 CFG_SYSTEMACE_BASE macro. For example: 1658 1659 #define CONFIG_SYSTEMACE 1660 #define CFG_SYSTEMACE_BASE 0xf0000000 1661 1662 When SystemACE support is added, the "ace" device type 1663 becomes available to the fat commands, i.e. fatls. 1664 1665- TFTP Fixed UDP Port: 1666 CONFIG_TFTP_PORT 1667 1668 If this is defined, the environment variable tftpsrcp 1669 is used to supply the TFTP UDP source port value. 1670 If tftpsrcp isn't defined, the normal pseudo-random port 1671 number generator is used. 1672 1673 Also, the environment variable tftpdstp is used to supply 1674 the TFTP UDP destination port value. If tftpdstp isn't 1675 defined, the normal port 69 is used. 1676 1677 The purpose for tftpsrcp is to allow a TFTP server to 1678 blindly start the TFTP transfer using the pre-configured 1679 target IP address and UDP port. This has the effect of 1680 "punching through" the (Windows XP) firewall, allowing 1681 the remainder of the TFTP transfer to proceed normally. 1682 A better solution is to properly configure the firewall, 1683 but sometimes that is not allowed. 1684 1685- Show boot progress: 1686 CONFIG_SHOW_BOOT_PROGRESS 1687 1688 Defining this option allows to add some board- 1689 specific code (calling a user-provided function 1690 "show_boot_progress(int)") that enables you to show 1691 the system's boot progress on some display (for 1692 example, some LED's) on your board. At the moment, 1693 the following checkpoints are implemented: 1694 1695Legacy uImage format: 1696 1697 Arg Where When 1698 1 common/cmd_bootm.c before attempting to boot an image 1699 -1 common/cmd_bootm.c Image header has bad magic number 1700 2 common/cmd_bootm.c Image header has correct magic number 1701 -2 common/cmd_bootm.c Image header has bad checksum 1702 3 common/cmd_bootm.c Image header has correct checksum 1703 -3 common/cmd_bootm.c Image data has bad checksum 1704 4 common/cmd_bootm.c Image data has correct checksum 1705 -4 common/cmd_bootm.c Image is for unsupported architecture 1706 5 common/cmd_bootm.c Architecture check OK 1707 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi) 1708 6 common/cmd_bootm.c Image Type check OK 1709 -6 common/cmd_bootm.c gunzip uncompression error 1710 -7 common/cmd_bootm.c Unimplemented compression type 1711 7 common/cmd_bootm.c Uncompression OK 1712 8 common/cmd_bootm.c No uncompress/copy overwrite error 1713 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX) 1714 1715 9 common/image.c Start initial ramdisk verification 1716 -10 common/image.c Ramdisk header has bad magic number 1717 -11 common/image.c Ramdisk header has bad checksum 1718 10 common/image.c Ramdisk header is OK 1719 -12 common/image.c Ramdisk data has bad checksum 1720 11 common/image.c Ramdisk data has correct checksum 1721 12 common/image.c Ramdisk verification complete, start loading 1722 -13 common/image.c Wrong Image Type (not PPC Linux Ramdisk) 1723 13 common/image.c Start multifile image verification 1724 14 common/image.c No initial ramdisk, no multifile, continue. 1725 1726 15 lib_<arch>/bootm.c All preparation done, transferring control to OS 1727 1728 -30 lib_ppc/board.c Fatal error, hang the system 1729 -31 post/post.c POST test failed, detected by post_output_backlog() 1730 -32 post/post.c POST test failed, detected by post_run_single() 1731 1732 34 common/cmd_doc.c before loading a Image from a DOC device 1733 -35 common/cmd_doc.c Bad usage of "doc" command 1734 35 common/cmd_doc.c correct usage of "doc" command 1735 -36 common/cmd_doc.c No boot device 1736 36 common/cmd_doc.c correct boot device 1737 -37 common/cmd_doc.c Unknown Chip ID on boot device 1738 37 common/cmd_doc.c correct chip ID found, device available 1739 -38 common/cmd_doc.c Read Error on boot device 1740 38 common/cmd_doc.c reading Image header from DOC device OK 1741 -39 common/cmd_doc.c Image header has bad magic number 1742 39 common/cmd_doc.c Image header has correct magic number 1743 -40 common/cmd_doc.c Error reading Image from DOC device 1744 40 common/cmd_doc.c Image header has correct magic number 1745 41 common/cmd_ide.c before loading a Image from a IDE device 1746 -42 common/cmd_ide.c Bad usage of "ide" command 1747 42 common/cmd_ide.c correct usage of "ide" command 1748 -43 common/cmd_ide.c No boot device 1749 43 common/cmd_ide.c boot device found 1750 -44 common/cmd_ide.c Device not available 1751 44 common/cmd_ide.c Device available 1752 -45 common/cmd_ide.c wrong partition selected 1753 45 common/cmd_ide.c partition selected 1754 -46 common/cmd_ide.c Unknown partition table 1755 46 common/cmd_ide.c valid partition table found 1756 -47 common/cmd_ide.c Invalid partition type 1757 47 common/cmd_ide.c correct partition type 1758 -48 common/cmd_ide.c Error reading Image Header on boot device 1759 48 common/cmd_ide.c reading Image Header from IDE device OK 1760 -49 common/cmd_ide.c Image header has bad magic number 1761 49 common/cmd_ide.c Image header has correct magic number 1762 -50 common/cmd_ide.c Image header has bad checksum 1763 50 common/cmd_ide.c Image header has correct checksum 1764 -51 common/cmd_ide.c Error reading Image from IDE device 1765 51 common/cmd_ide.c reading Image from IDE device OK 1766 52 common/cmd_nand.c before loading a Image from a NAND device 1767 -53 common/cmd_nand.c Bad usage of "nand" command 1768 53 common/cmd_nand.c correct usage of "nand" command 1769 -54 common/cmd_nand.c No boot device 1770 54 common/cmd_nand.c boot device found 1771 -55 common/cmd_nand.c Unknown Chip ID on boot device 1772 55 common/cmd_nand.c correct chip ID found, device available 1773 -56 common/cmd_nand.c Error reading Image Header on boot device 1774 56 common/cmd_nand.c reading Image Header from NAND device OK 1775 -57 common/cmd_nand.c Image header has bad magic number 1776 57 common/cmd_nand.c Image header has correct magic number 1777 -58 common/cmd_nand.c Error reading Image from NAND device 1778 58 common/cmd_nand.c reading Image from NAND device OK 1779 1780 -60 common/env_common.c Environment has a bad CRC, using default 1781 1782 64 net/eth.c starting with Ethernetconfiguration. 1783 -64 net/eth.c no Ethernet found. 1784 65 net/eth.c Ethernet found. 1785 1786 -80 common/cmd_net.c usage wrong 1787 80 common/cmd_net.c before calling NetLoop() 1788 -81 common/cmd_net.c some error in NetLoop() occured 1789 81 common/cmd_net.c NetLoop() back without error 1790 -82 common/cmd_net.c size == 0 (File with size 0 loaded) 1791 82 common/cmd_net.c trying automatic boot 1792 83 common/cmd_net.c running autoscript 1793 -83 common/cmd_net.c some error in automatic boot or autoscript 1794 84 common/cmd_net.c end without errors 1795 1796FIT uImage format: 1797 1798 Arg Where When 1799 100 common/cmd_bootm.c Kernel FIT Image has correct format 1800 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format 1801 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration 1802 -101 common/cmd_bootm.c Can't get configuration for kernel subimage 1803 102 common/cmd_bootm.c Kernel unit name specified 1804 -103 common/cmd_bootm.c Can't get kernel subimage node offset 1805 103 common/cmd_bootm.c Found configuration node 1806 104 common/cmd_bootm.c Got kernel subimage node offset 1807 -104 common/cmd_bootm.c Kernel subimage hash verification failed 1808 105 common/cmd_bootm.c Kernel subimage hash verification OK 1809 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture 1810 106 common/cmd_bootm.c Architecture check OK 1811 -106 common/cmd_bootm.c Kernel subimage has wrong typea 1812 107 common/cmd_bootm.c Kernel subimge type OK 1813 -107 common/cmd_bootm.c Can't get kernel subimage data/size 1814 108 common/cmd_bootm.c Got kernel subimage data/size 1815 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT) 1816 -109 common/cmd_bootm.c Can't get kernel subimage type 1817 -110 common/cmd_bootm.c Can't get kernel subimage comp 1818 -111 common/cmd_bootm.c Can't get kernel subimage os 1819 -112 common/cmd_bootm.c Can't get kernel subimage load address 1820 -113 common/cmd_bootm.c Image uncompress/copy overwrite error 1821 1822 120 common/image.c Start initial ramdisk verification 1823 -120 common/image.c Ramdisk FIT image has incorrect format 1824 121 common/image.c Ramdisk FIT image has correct format 1825 122 common/image.c No Ramdisk subimage unit name, using configuration 1826 -122 common/image.c Can't get configuration for ramdisk subimage 1827 123 common/image.c Ramdisk unit name specified 1828 -124 common/image.c Can't get ramdisk subimage node offset 1829 125 common/image.c Got ramdisk subimage node offset 1830 -125 common/image.c Ramdisk subimage hash verification failed 1831 126 common/image.c Ramdisk subimage hash verification OK 1832 -126 common/image.c Ramdisk subimage for unsupported architecture 1833 127 common/image.c Architecture check OK 1834 -127 common/image.c Can't get ramdisk subimage data/size 1835 128 common/image.c Got ramdisk subimage data/size 1836 129 common/image.c Can't get ramdisk load address 1837 -129 common/image.c Got ramdisk load address 1838 1839 -130 common/cmd_doc.c Icorrect FIT image format 1840 131 common/cmd_doc.c FIT image format OK 1841 1842 -140 common/cmd_ide.c Icorrect FIT image format 1843 141 common/cmd_ide.c FIT image format OK 1844 1845 -150 common/cmd_nand.c Icorrect FIT image format 1846 151 common/cmd_nand.c FIT image format OK 1847 1848 1849Modem Support: 1850-------------- 1851 1852[so far only for SMDK2400 and TRAB boards] 1853 1854- Modem support endable: 1855 CONFIG_MODEM_SUPPORT 1856 1857- RTS/CTS Flow control enable: 1858 CONFIG_HWFLOW 1859 1860- Modem debug support: 1861 CONFIG_MODEM_SUPPORT_DEBUG 1862 1863 Enables debugging stuff (char screen[1024], dbg()) 1864 for modem support. Useful only with BDI2000. 1865 1866- Interrupt support (PPC): 1867 1868 There are common interrupt_init() and timer_interrupt() 1869 for all PPC archs. interrupt_init() calls interrupt_init_cpu() 1870 for cpu specific initialization. interrupt_init_cpu() 1871 should set decrementer_count to appropriate value. If 1872 cpu resets decrementer automatically after interrupt 1873 (ppc4xx) it should set decrementer_count to zero. 1874 timer_interrupt() calls timer_interrupt_cpu() for cpu 1875 specific handling. If board has watchdog / status_led 1876 / other_activity_monitor it works automatically from 1877 general timer_interrupt(). 1878 1879- General: 1880 1881 In the target system modem support is enabled when a 1882 specific key (key combination) is pressed during 1883 power-on. Otherwise U-Boot will boot normally 1884 (autoboot). The key_pressed() fuction is called from 1885 board_init(). Currently key_pressed() is a dummy 1886 function, returning 1 and thus enabling modem 1887 initialization. 1888 1889 If there are no modem init strings in the 1890 environment, U-Boot proceed to autoboot; the 1891 previous output (banner, info printfs) will be 1892 supressed, though. 1893 1894 See also: doc/README.Modem 1895 1896 1897Configuration Settings: 1898----------------------- 1899 1900- CFG_LONGHELP: Defined when you want long help messages included; 1901 undefine this when you're short of memory. 1902 1903- CFG_PROMPT: This is what U-Boot prints on the console to 1904 prompt for user input. 1905 1906- CFG_CBSIZE: Buffer size for input from the Console 1907 1908- CFG_PBSIZE: Buffer size for Console output 1909 1910- CFG_MAXARGS: max. Number of arguments accepted for monitor commands 1911 1912- CFG_BARGSIZE: Buffer size for Boot Arguments which are passed to 1913 the application (usually a Linux kernel) when it is 1914 booted 1915 1916- CFG_BAUDRATE_TABLE: 1917 List of legal baudrate settings for this board. 1918 1919- CFG_CONSOLE_INFO_QUIET 1920 Suppress display of console information at boot. 1921 1922- CFG_CONSOLE_IS_IN_ENV 1923 If the board specific function 1924 extern int overwrite_console (void); 1925 returns 1, the stdin, stderr and stdout are switched to the 1926 serial port, else the settings in the environment are used. 1927 1928- CFG_CONSOLE_OVERWRITE_ROUTINE 1929 Enable the call to overwrite_console(). 1930 1931- CFG_CONSOLE_ENV_OVERWRITE 1932 Enable overwrite of previous console environment settings. 1933 1934- CFG_MEMTEST_START, CFG_MEMTEST_END: 1935 Begin and End addresses of the area used by the 1936 simple memory test. 1937 1938- CFG_ALT_MEMTEST: 1939 Enable an alternate, more extensive memory test. 1940 1941- CFG_MEMTEST_SCRATCH: 1942 Scratch address used by the alternate memory test 1943 You only need to set this if address zero isn't writeable 1944 1945- CFG_MEM_TOP_HIDE (PPC only): 1946 If CFG_MEM_TOP_HIDE is defined in the board config header, 1947 this specified memory area will get subtracted from the top 1948 (end) of ram and won't get "touched" at all by U-Boot. By 1949 fixing up gd->ram_size the Linux kernel should gets passed 1950 the now "corrected" memory size and won't touch it either. 1951 This should work for arch/ppc and arch/powerpc. Only Linux 1952 board ports in arch/powerpc with bootwrapper support that 1953 recalculate the memory size from the SDRAM controller setup 1954 will have to get fixed in Linux additionally. 1955 1956 This option can be used as a workaround for the 440EPx/GRx 1957 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't 1958 be touched. 1959 1960 WARNING: Please make sure that this value is a multiple of 1961 the Linux page size (normally 4k). If this is not the case, 1962 then the end address of the Linux memory will be located at a 1963 non page size aligned address and this could cause major 1964 problems. 1965 1966- CFG_TFTP_LOADADDR: 1967 Default load address for network file downloads 1968 1969- CFG_LOADS_BAUD_CHANGE: 1970 Enable temporary baudrate change while serial download 1971 1972- CFG_SDRAM_BASE: 1973 Physical start address of SDRAM. _Must_ be 0 here. 1974 1975- CFG_MBIO_BASE: 1976 Physical start address of Motherboard I/O (if using a 1977 Cogent motherboard) 1978 1979- CFG_FLASH_BASE: 1980 Physical start address of Flash memory. 1981 1982- CFG_MONITOR_BASE: 1983 Physical start address of boot monitor code (set by 1984 make config files to be same as the text base address 1985 (TEXT_BASE) used when linking) - same as 1986 CFG_FLASH_BASE when booting from flash. 1987 1988- CFG_MONITOR_LEN: 1989 Size of memory reserved for monitor code, used to 1990 determine _at_compile_time_ (!) if the environment is 1991 embedded within the U-Boot image, or in a separate 1992 flash sector. 1993 1994- CFG_MALLOC_LEN: 1995 Size of DRAM reserved for malloc() use. 1996 1997- CFG_BOOTM_LEN: 1998 Normally compressed uImages are limited to an 1999 uncompressed size of 8 MBytes. If this is not enough, 2000 you can define CFG_BOOTM_LEN in your board config file 2001 to adjust this setting to your needs. 2002 2003- CFG_BOOTMAPSZ: 2004 Maximum size of memory mapped by the startup code of 2005 the Linux kernel; all data that must be processed by 2006 the Linux kernel (bd_info, boot arguments, FDT blob if 2007 used) must be put below this limit, unless "bootm_low" 2008 enviroment variable is defined and non-zero. In such case 2009 all data for the Linux kernel must be between "bootm_low" 2010 and "bootm_low" + CFG_BOOTMAPSZ. 2011 2012- CFG_MAX_FLASH_BANKS: 2013 Max number of Flash memory banks 2014 2015- CFG_MAX_FLASH_SECT: 2016 Max number of sectors on a Flash chip 2017 2018- CFG_FLASH_ERASE_TOUT: 2019 Timeout for Flash erase operations (in ms) 2020 2021- CFG_FLASH_WRITE_TOUT: 2022 Timeout for Flash write operations (in ms) 2023 2024- CFG_FLASH_LOCK_TOUT 2025 Timeout for Flash set sector lock bit operation (in ms) 2026 2027- CFG_FLASH_UNLOCK_TOUT 2028 Timeout for Flash clear lock bits operation (in ms) 2029 2030- CFG_FLASH_PROTECTION 2031 If defined, hardware flash sectors protection is used 2032 instead of U-Boot software protection. 2033 2034- CFG_DIRECT_FLASH_TFTP: 2035 2036 Enable TFTP transfers directly to flash memory; 2037 without this option such a download has to be 2038 performed in two steps: (1) download to RAM, and (2) 2039 copy from RAM to flash. 2040 2041 The two-step approach is usually more reliable, since 2042 you can check if the download worked before you erase 2043 the flash, but in some situations (when sytem RAM is 2044 too limited to allow for a tempory copy of the 2045 downloaded image) this option may be very useful. 2046 2047- CFG_FLASH_CFI: 2048 Define if the flash driver uses extra elements in the 2049 common flash structure for storing flash geometry. 2050 2051- CFG_FLASH_CFI_DRIVER 2052 This option also enables the building of the cfi_flash driver 2053 in the drivers directory 2054 2055- CFG_FLASH_USE_BUFFER_WRITE 2056 Use buffered writes to flash. 2057 2058- CONFIG_FLASH_SPANSION_S29WS_N 2059 s29ws-n MirrorBit flash has non-standard addresses for buffered 2060 write commands. 2061 2062- CFG_FLASH_QUIET_TEST 2063 If this option is defined, the common CFI flash doesn't 2064 print it's warning upon not recognized FLASH banks. This 2065 is useful, if some of the configured banks are only 2066 optionally available. 2067 2068- CONFIG_FLASH_SHOW_PROGRESS 2069 If defined (must be an integer), print out countdown 2070 digits and dots. Recommended value: 45 (9..1) for 80 2071 column displays, 15 (3..1) for 40 column displays. 2072 2073- CFG_RX_ETH_BUFFER: 2074 Defines the number of ethernet receive buffers. On some 2075 ethernet controllers it is recommended to set this value 2076 to 8 or even higher (EEPRO100 or 405 EMAC), since all 2077 buffers can be full shortly after enabling the interface 2078 on high ethernet traffic. 2079 Defaults to 4 if not defined. 2080 2081The following definitions that deal with the placement and management 2082of environment data (variable area); in general, we support the 2083following configurations: 2084 2085- CFG_ENV_IS_IN_FLASH: 2086 2087 Define this if the environment is in flash memory. 2088 2089 a) The environment occupies one whole flash sector, which is 2090 "embedded" in the text segment with the U-Boot code. This 2091 happens usually with "bottom boot sector" or "top boot 2092 sector" type flash chips, which have several smaller 2093 sectors at the start or the end. For instance, such a 2094 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In 2095 such a case you would place the environment in one of the 2096 4 kB sectors - with U-Boot code before and after it. With 2097 "top boot sector" type flash chips, you would put the 2098 environment in one of the last sectors, leaving a gap 2099 between U-Boot and the environment. 2100 2101 - CFG_ENV_OFFSET: 2102 2103 Offset of environment data (variable area) to the 2104 beginning of flash memory; for instance, with bottom boot 2105 type flash chips the second sector can be used: the offset 2106 for this sector is given here. 2107 2108 CFG_ENV_OFFSET is used relative to CFG_FLASH_BASE. 2109 2110 - CFG_ENV_ADDR: 2111 2112 This is just another way to specify the start address of 2113 the flash sector containing the environment (instead of 2114 CFG_ENV_OFFSET). 2115 2116 - CFG_ENV_SECT_SIZE: 2117 2118 Size of the sector containing the environment. 2119 2120 2121 b) Sometimes flash chips have few, equal sized, BIG sectors. 2122 In such a case you don't want to spend a whole sector for 2123 the environment. 2124 2125 - CFG_ENV_SIZE: 2126 2127 If you use this in combination with CFG_ENV_IS_IN_FLASH 2128 and CFG_ENV_SECT_SIZE, you can specify to use only a part 2129 of this flash sector for the environment. This saves 2130 memory for the RAM copy of the environment. 2131 2132 It may also save flash memory if you decide to use this 2133 when your environment is "embedded" within U-Boot code, 2134 since then the remainder of the flash sector could be used 2135 for U-Boot code. It should be pointed out that this is 2136 STRONGLY DISCOURAGED from a robustness point of view: 2137 updating the environment in flash makes it always 2138 necessary to erase the WHOLE sector. If something goes 2139 wrong before the contents has been restored from a copy in 2140 RAM, your target system will be dead. 2141 2142 - CFG_ENV_ADDR_REDUND 2143 CFG_ENV_SIZE_REDUND 2144 2145 These settings describe a second storage area used to hold 2146 a redundand copy of the environment data, so that there is 2147 a valid backup copy in case there is a power failure during 2148 a "saveenv" operation. 2149 2150BE CAREFUL! Any changes to the flash layout, and some changes to the 2151source code will make it necessary to adapt <board>/u-boot.lds* 2152accordingly! 2153 2154 2155- CFG_ENV_IS_IN_NVRAM: 2156 2157 Define this if you have some non-volatile memory device 2158 (NVRAM, battery buffered SRAM) which you want to use for the 2159 environment. 2160 2161 - CFG_ENV_ADDR: 2162 - CFG_ENV_SIZE: 2163 2164 These two #defines are used to determin the memory area you 2165 want to use for environment. It is assumed that this memory 2166 can just be read and written to, without any special 2167 provision. 2168 2169BE CAREFUL! The first access to the environment happens quite early 2170in U-Boot initalization (when we try to get the setting of for the 2171console baudrate). You *MUST* have mappend your NVRAM area then, or 2172U-Boot will hang. 2173 2174Please note that even with NVRAM we still use a copy of the 2175environment in RAM: we could work on NVRAM directly, but we want to 2176keep settings there always unmodified except somebody uses "saveenv" 2177to save the current settings. 2178 2179 2180- CFG_ENV_IS_IN_EEPROM: 2181 2182 Use this if you have an EEPROM or similar serial access 2183 device and a driver for it. 2184 2185 - CFG_ENV_OFFSET: 2186 - CFG_ENV_SIZE: 2187 2188 These two #defines specify the offset and size of the 2189 environment area within the total memory of your EEPROM. 2190 2191 - CFG_I2C_EEPROM_ADDR: 2192 If defined, specified the chip address of the EEPROM device. 2193 The default address is zero. 2194 2195 - CFG_EEPROM_PAGE_WRITE_BITS: 2196 If defined, the number of bits used to address bytes in a 2197 single page in the EEPROM device. A 64 byte page, for example 2198 would require six bits. 2199 2200 - CFG_EEPROM_PAGE_WRITE_DELAY_MS: 2201 If defined, the number of milliseconds to delay between 2202 page writes. The default is zero milliseconds. 2203 2204 - CFG_I2C_EEPROM_ADDR_LEN: 2205 The length in bytes of the EEPROM memory array address. Note 2206 that this is NOT the chip address length! 2207 2208 - CFG_I2C_EEPROM_ADDR_OVERFLOW: 2209 EEPROM chips that implement "address overflow" are ones 2210 like Catalyst 24WC04/08/16 which has 9/10/11 bits of 2211 address and the extra bits end up in the "chip address" bit 2212 slots. This makes a 24WC08 (1Kbyte) chip look like four 256 2213 byte chips. 2214 2215 Note that we consider the length of the address field to 2216 still be one byte because the extra address bits are hidden 2217 in the chip address. 2218 2219 - CFG_EEPROM_SIZE: 2220 The size in bytes of the EEPROM device. 2221 2222 2223- CFG_ENV_IS_IN_DATAFLASH: 2224 2225 Define this if you have a DataFlash memory device which you 2226 want to use for the environment. 2227 2228 - CFG_ENV_OFFSET: 2229 - CFG_ENV_ADDR: 2230 - CFG_ENV_SIZE: 2231 2232 These three #defines specify the offset and size of the 2233 environment area within the total memory of your DataFlash placed 2234 at the specified address. 2235 2236- CFG_ENV_IS_IN_NAND: 2237 2238 Define this if you have a NAND device which you want to use 2239 for the environment. 2240 2241 - CFG_ENV_OFFSET: 2242 - CFG_ENV_SIZE: 2243 2244 These two #defines specify the offset and size of the environment 2245 area within the first NAND device. 2246 2247 - CFG_ENV_OFFSET_REDUND 2248 2249 This setting describes a second storage area of CFG_ENV_SIZE 2250 size used to hold a redundant copy of the environment data, 2251 so that there is a valid backup copy in case there is a 2252 power failure during a "saveenv" operation. 2253 2254 Note: CFG_ENV_OFFSET and CFG_ENV_OFFSET_REDUND must be aligned 2255 to a block boundary, and CFG_ENV_SIZE must be a multiple of 2256 the NAND devices block size. 2257 2258- CFG_SPI_INIT_OFFSET 2259 2260 Defines offset to the initial SPI buffer area in DPRAM. The 2261 area is used at an early stage (ROM part) if the environment 2262 is configured to reside in the SPI EEPROM: We need a 520 byte 2263 scratch DPRAM area. It is used between the two initialization 2264 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems 2265 to be a good choice since it makes it far enough from the 2266 start of the data area as well as from the stack pointer. 2267 2268Please note that the environment is read-only until the monitor 2269has been relocated to RAM and a RAM copy of the environment has been 2270created; also, when using EEPROM you will have to use getenv_r() 2271until then to read environment variables. 2272 2273The environment is protected by a CRC32 checksum. Before the monitor 2274is relocated into RAM, as a result of a bad CRC you will be working 2275with the compiled-in default environment - *silently*!!! [This is 2276necessary, because the first environment variable we need is the 2277"baudrate" setting for the console - if we have a bad CRC, we don't 2278have any device yet where we could complain.] 2279 2280Note: once the monitor has been relocated, then it will complain if 2281the default environment is used; a new CRC is computed as soon as you 2282use the "saveenv" command to store a valid environment. 2283 2284- CFG_FAULT_ECHO_LINK_DOWN: 2285 Echo the inverted Ethernet link state to the fault LED. 2286 2287 Note: If this option is active, then CFG_FAULT_MII_ADDR 2288 also needs to be defined. 2289 2290- CFG_FAULT_MII_ADDR: 2291 MII address of the PHY to check for the Ethernet link state. 2292 2293- CFG_64BIT_VSPRINTF: 2294 Makes vsprintf (and all *printf functions) support printing 2295 of 64bit values by using the L quantifier 2296 2297- CFG_64BIT_STRTOUL: 2298 Adds simple_strtoull that returns a 64bit value 2299 2300Low Level (hardware related) configuration options: 2301--------------------------------------------------- 2302 2303- CFG_CACHELINE_SIZE: 2304 Cache Line Size of the CPU. 2305 2306- CFG_DEFAULT_IMMR: 2307 Default address of the IMMR after system reset. 2308 2309 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU, 2310 and RPXsuper) to be able to adjust the position of 2311 the IMMR register after a reset. 2312 2313- Floppy Disk Support: 2314 CFG_FDC_DRIVE_NUMBER 2315 2316 the default drive number (default value 0) 2317 2318 CFG_ISA_IO_STRIDE 2319 2320 defines the spacing between fdc chipset registers 2321 (default value 1) 2322 2323 CFG_ISA_IO_OFFSET 2324 2325 defines the offset of register from address. It 2326 depends on which part of the data bus is connected to 2327 the fdc chipset. (default value 0) 2328 2329 If CFG_ISA_IO_STRIDE CFG_ISA_IO_OFFSET and 2330 CFG_FDC_DRIVE_NUMBER are undefined, they take their 2331 default value. 2332 2333 if CFG_FDC_HW_INIT is defined, then the function 2334 fdc_hw_init() is called at the beginning of the FDC 2335 setup. fdc_hw_init() must be provided by the board 2336 source code. It is used to make hardware dependant 2337 initializations. 2338 2339- CFG_IMMR: Physical address of the Internal Memory. 2340 DO NOT CHANGE unless you know exactly what you're 2341 doing! (11-4) [MPC8xx/82xx systems only] 2342 2343- CFG_INIT_RAM_ADDR: 2344 2345 Start address of memory area that can be used for 2346 initial data and stack; please note that this must be 2347 writable memory that is working WITHOUT special 2348 initialization, i. e. you CANNOT use normal RAM which 2349 will become available only after programming the 2350 memory controller and running certain initialization 2351 sequences. 2352 2353 U-Boot uses the following memory types: 2354 - MPC8xx and MPC8260: IMMR (internal memory of the CPU) 2355 - MPC824X: data cache 2356 - PPC4xx: data cache 2357 2358- CFG_GBL_DATA_OFFSET: 2359 2360 Offset of the initial data structure in the memory 2361 area defined by CFG_INIT_RAM_ADDR. Usually 2362 CFG_GBL_DATA_OFFSET is chosen such that the initial 2363 data is located at the end of the available space 2364 (sometimes written as (CFG_INIT_RAM_END - 2365 CFG_INIT_DATA_SIZE), and the initial stack is just 2366 below that area (growing from (CFG_INIT_RAM_ADDR + 2367 CFG_GBL_DATA_OFFSET) downward. 2368 2369 Note: 2370 On the MPC824X (or other systems that use the data 2371 cache for initial memory) the address chosen for 2372 CFG_INIT_RAM_ADDR is basically arbitrary - it must 2373 point to an otherwise UNUSED address space between 2374 the top of RAM and the start of the PCI space. 2375 2376- CFG_SIUMCR: SIU Module Configuration (11-6) 2377 2378- CFG_SYPCR: System Protection Control (11-9) 2379 2380- CFG_TBSCR: Time Base Status and Control (11-26) 2381 2382- CFG_PISCR: Periodic Interrupt Status and Control (11-31) 2383 2384- CFG_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30) 2385 2386- CFG_SCCR: System Clock and reset Control Register (15-27) 2387 2388- CFG_OR_TIMING_SDRAM: 2389 SDRAM timing 2390 2391- CFG_MAMR_PTA: 2392 periodic timer for refresh 2393 2394- CFG_DER: Debug Event Register (37-47) 2395 2396- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CFG_REMAP_OR_AM, 2397 CFG_PRELIM_OR_AM, CFG_OR_TIMING_FLASH, CFG_OR0_REMAP, 2398 CFG_OR0_PRELIM, CFG_BR0_PRELIM, CFG_OR1_REMAP, CFG_OR1_PRELIM, 2399 CFG_BR1_PRELIM: 2400 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH) 2401 2402- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE, 2403 CFG_OR_TIMING_SDRAM, CFG_OR2_PRELIM, CFG_BR2_PRELIM, 2404 CFG_OR3_PRELIM, CFG_BR3_PRELIM: 2405 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM) 2406 2407- CFG_MAMR_PTA, CFG_MPTPR_2BK_4K, CFG_MPTPR_1BK_4K, CFG_MPTPR_2BK_8K, 2408 CFG_MPTPR_1BK_8K, CFG_MAMR_8COL, CFG_MAMR_9COL: 2409 Machine Mode Register and Memory Periodic Timer 2410 Prescaler definitions (SDRAM timing) 2411 2412- CFG_I2C_UCODE_PATCH, CFG_I2C_DPMEM_OFFSET [0x1FC0]: 2413 enable I2C microcode relocation patch (MPC8xx); 2414 define relocation offset in DPRAM [DSP2] 2415 2416- CFG_SMC_UCODE_PATCH, CFG_SMC_DPMEM_OFFSET [0x1FC0]: 2417 enable SMC microcode relocation patch (MPC8xx); 2418 define relocation offset in DPRAM [SMC1] 2419 2420- CFG_SPI_UCODE_PATCH, CFG_SPI_DPMEM_OFFSET [0x1FC0]: 2421 enable SPI microcode relocation patch (MPC8xx); 2422 define relocation offset in DPRAM [SCC4] 2423 2424- CFG_USE_OSCCLK: 2425 Use OSCM clock mode on MBX8xx board. Be careful, 2426 wrong setting might damage your board. Read 2427 doc/README.MBX before setting this variable! 2428 2429- CFG_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only) 2430 Offset of the bootmode word in DPRAM used by post 2431 (Power On Self Tests). This definition overrides 2432 #define'd default value in commproc.h resp. 2433 cpm_8260.h. 2434 2435- CFG_PCI_SLV_MEM_LOCAL, CFG_PCI_SLV_MEM_BUS, CFG_PICMR0_MASK_ATTRIB, 2436 CFG_PCI_MSTR0_LOCAL, CFG_PCIMSK0_MASK, CFG_PCI_MSTR1_LOCAL, 2437 CFG_PCIMSK1_MASK, CFG_PCI_MSTR_MEM_LOCAL, CFG_PCI_MSTR_MEM_BUS, 2438 CFG_CPU_PCI_MEM_START, CFG_PCI_MSTR_MEM_SIZE, CFG_POCMR0_MASK_ATTRIB, 2439 CFG_PCI_MSTR_MEMIO_LOCAL, CFG_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START, 2440 CFG_PCI_MSTR_MEMIO_SIZE, CFG_POCMR1_MASK_ATTRIB, CFG_PCI_MSTR_IO_LOCAL, 2441 CFG_PCI_MSTR_IO_BUS, CFG_CPU_PCI_IO_START, CFG_PCI_MSTR_IO_SIZE, 2442 CFG_POCMR2_MASK_ATTRIB: (MPC826x only) 2443 Overrides the default PCI memory map in cpu/mpc8260/pci.c if set. 2444 2445- CONFIG_SPD_EEPROM 2446 Get DDR timing information from an I2C EEPROM. Common 2447 with pluggable memory modules such as SODIMMs 2448 2449 SPD_EEPROM_ADDRESS 2450 I2C address of the SPD EEPROM 2451 2452- CFG_SPD_BUS_NUM 2453 If SPD EEPROM is on an I2C bus other than the first 2454 one, specify here. Note that the value must resolve 2455 to something your driver can deal with. 2456 2457- CFG_83XX_DDR_USES_CS0 2458 Only for 83xx systems. If specified, then DDR should 2459 be configured using CS0 and CS1 instead of CS2 and CS3. 2460 2461- CFG_83XX_DDR_USES_CS0 2462 Only for 83xx systems. If specified, then DDR should 2463 be configured using CS0 and CS1 instead of CS2 and CS3. 2464 2465- CONFIG_ETHER_ON_FEC[12] 2466 Define to enable FEC[12] on a 8xx series processor. 2467 2468- CONFIG_FEC[12]_PHY 2469 Define to the hardcoded PHY address which corresponds 2470 to the given FEC; i. e. 2471 #define CONFIG_FEC1_PHY 4 2472 means that the PHY with address 4 is connected to FEC1 2473 2474 When set to -1, means to probe for first available. 2475 2476- CONFIG_FEC[12]_PHY_NORXERR 2477 The PHY does not have a RXERR line (RMII only). 2478 (so program the FEC to ignore it). 2479 2480- CONFIG_RMII 2481 Enable RMII mode for all FECs. 2482 Note that this is a global option, we can't 2483 have one FEC in standard MII mode and another in RMII mode. 2484 2485- CONFIG_CRC32_VERIFY 2486 Add a verify option to the crc32 command. 2487 The syntax is: 2488 2489 => crc32 -v <address> <count> <crc32> 2490 2491 Where address/count indicate a memory area 2492 and crc32 is the correct crc32 which the 2493 area should have. 2494 2495- CONFIG_LOOPW 2496 Add the "loopw" memory command. This only takes effect if 2497 the memory commands are activated globally (CONFIG_CMD_MEM). 2498 2499- CONFIG_MX_CYCLIC 2500 Add the "mdc" and "mwc" memory commands. These are cyclic 2501 "md/mw" commands. 2502 Examples: 2503 2504 => mdc.b 10 4 500 2505 This command will print 4 bytes (10,11,12,13) each 500 ms. 2506 2507 => mwc.l 100 12345678 10 2508 This command will write 12345678 to address 100 all 10 ms. 2509 2510 This only takes effect if the memory commands are activated 2511 globally (CONFIG_CMD_MEM). 2512 2513- CONFIG_SKIP_LOWLEVEL_INIT 2514- CONFIG_SKIP_RELOCATE_UBOOT 2515 2516 [ARM only] If these variables are defined, then 2517 certain low level initializations (like setting up 2518 the memory controller) are omitted and/or U-Boot does 2519 not relocate itself into RAM. 2520 Normally these variables MUST NOT be defined. The 2521 only exception is when U-Boot is loaded (to RAM) by 2522 some other boot loader or by a debugger which 2523 performs these intializations itself. 2524 2525 2526Building the Software: 2527====================== 2528 2529Building U-Boot has been tested in several native build environments 2530and in many different cross environments. Of course we cannot support 2531all possibly existing versions of cross development tools in all 2532(potentially obsolete) versions. In case of tool chain problems we 2533recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK) 2534which is extensively used to build and test U-Boot. 2535 2536If you are not using a native environment, it is assumed that you 2537have GNU cross compiling tools available in your path. In this case, 2538you must set the environment variable CROSS_COMPILE in your shell. 2539Note that no changes to the Makefile or any other source files are 2540necessary. For example using the ELDK on a 4xx CPU, please enter: 2541 2542 $ CROSS_COMPILE=ppc_4xx- 2543 $ export CROSS_COMPILE 2544 2545U-Boot is intended to be simple to build. After installing the 2546sources you must configure U-Boot for one specific board type. This 2547is done by typing: 2548 2549 make NAME_config 2550 2551where "NAME_config" is the name of one of the existing configu- 2552rations; see the main Makefile for supported names. 2553 2554Note: for some board special configuration names may exist; check if 2555 additional information is available from the board vendor; for 2556 instance, the TQM823L systems are available without (standard) 2557 or with LCD support. You can select such additional "features" 2558 when chosing the configuration, i. e. 2559 2560 make TQM823L_config 2561 - will configure for a plain TQM823L, i. e. no LCD support 2562 2563 make TQM823L_LCD_config 2564 - will configure for a TQM823L with U-Boot console on LCD 2565 2566 etc. 2567 2568 2569Finally, type "make all", and you should get some working U-Boot 2570images ready for download to / installation on your system: 2571 2572- "u-boot.bin" is a raw binary image 2573- "u-boot" is an image in ELF binary format 2574- "u-boot.srec" is in Motorola S-Record format 2575 2576By default the build is performed locally and the objects are saved 2577in the source directory. One of the two methods can be used to change 2578this behavior and build U-Boot to some external directory: 2579 25801. Add O= to the make command line invocations: 2581 2582 make O=/tmp/build distclean 2583 make O=/tmp/build NAME_config 2584 make O=/tmp/build all 2585 25862. Set environment variable BUILD_DIR to point to the desired location: 2587 2588 export BUILD_DIR=/tmp/build 2589 make distclean 2590 make NAME_config 2591 make all 2592 2593Note that the command line "O=" setting overrides the BUILD_DIR environment 2594variable. 2595 2596 2597Please be aware that the Makefiles assume you are using GNU make, so 2598for instance on NetBSD you might need to use "gmake" instead of 2599native "make". 2600 2601 2602If the system board that you have is not listed, then you will need 2603to port U-Boot to your hardware platform. To do this, follow these 2604steps: 2605 26061. Add a new configuration option for your board to the toplevel 2607 "Makefile" and to the "MAKEALL" script, using the existing 2608 entries as examples. Note that here and at many other places 2609 boards and other names are listed in alphabetical sort order. Please 2610 keep this order. 26112. Create a new directory to hold your board specific code. Add any 2612 files you need. In your board directory, you will need at least 2613 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds". 26143. Create a new configuration file "include/configs/<board>.h" for 2615 your board 26163. If you're porting U-Boot to a new CPU, then also create a new 2617 directory to hold your CPU specific code. Add any files you need. 26184. Run "make <board>_config" with your new name. 26195. Type "make", and you should get a working "u-boot.srec" file 2620 to be installed on your target system. 26216. Debug and solve any problems that might arise. 2622 [Of course, this last step is much harder than it sounds.] 2623 2624 2625Testing of U-Boot Modifications, Ports to New Hardware, etc.: 2626============================================================== 2627 2628If you have modified U-Boot sources (for instance added a new board 2629or support for new devices, a new CPU, etc.) you are expected to 2630provide feedback to the other developers. The feedback normally takes 2631the form of a "patch", i. e. a context diff against a certain (latest 2632official or latest in the git repository) version of U-Boot sources. 2633 2634But before you submit such a patch, please verify that your modifi- 2635cation did not break existing code. At least make sure that *ALL* of 2636the supported boards compile WITHOUT ANY compiler warnings. To do so, 2637just run the "MAKEALL" script, which will configure and build U-Boot 2638for ALL supported system. Be warned, this will take a while. You can 2639select which (cross) compiler to use by passing a `CROSS_COMPILE' 2640environment variable to the script, i. e. to use the ELDK cross tools 2641you can type 2642 2643 CROSS_COMPILE=ppc_8xx- MAKEALL 2644 2645or to build on a native PowerPC system you can type 2646 2647 CROSS_COMPILE=' ' MAKEALL 2648 2649When using the MAKEALL script, the default behaviour is to build 2650U-Boot in the source directory. This location can be changed by 2651setting the BUILD_DIR environment variable. Also, for each target 2652built, the MAKEALL script saves two log files (<target>.ERR and 2653<target>.MAKEALL) in the <source dir>/LOG directory. This default 2654location can be changed by setting the MAKEALL_LOGDIR environment 2655variable. For example: 2656 2657 export BUILD_DIR=/tmp/build 2658 export MAKEALL_LOGDIR=/tmp/log 2659 CROSS_COMPILE=ppc_8xx- MAKEALL 2660 2661With the above settings build objects are saved in the /tmp/build, 2662log files are saved in the /tmp/log and the source tree remains clean 2663during the whole build process. 2664 2665 2666See also "U-Boot Porting Guide" below. 2667 2668 2669Monitor Commands - Overview: 2670============================ 2671 2672go - start application at address 'addr' 2673run - run commands in an environment variable 2674bootm - boot application image from memory 2675bootp - boot image via network using BootP/TFTP protocol 2676tftpboot- boot image via network using TFTP protocol 2677 and env variables "ipaddr" and "serverip" 2678 (and eventually "gatewayip") 2679rarpboot- boot image via network using RARP/TFTP protocol 2680diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd' 2681loads - load S-Record file over serial line 2682loadb - load binary file over serial line (kermit mode) 2683md - memory display 2684mm - memory modify (auto-incrementing) 2685nm - memory modify (constant address) 2686mw - memory write (fill) 2687cp - memory copy 2688cmp - memory compare 2689crc32 - checksum calculation 2690imd - i2c memory display 2691imm - i2c memory modify (auto-incrementing) 2692inm - i2c memory modify (constant address) 2693imw - i2c memory write (fill) 2694icrc32 - i2c checksum calculation 2695iprobe - probe to discover valid I2C chip addresses 2696iloop - infinite loop on address range 2697isdram - print SDRAM configuration information 2698sspi - SPI utility commands 2699base - print or set address offset 2700printenv- print environment variables 2701setenv - set environment variables 2702saveenv - save environment variables to persistent storage 2703protect - enable or disable FLASH write protection 2704erase - erase FLASH memory 2705flinfo - print FLASH memory information 2706bdinfo - print Board Info structure 2707iminfo - print header information for application image 2708coninfo - print console devices and informations 2709ide - IDE sub-system 2710loop - infinite loop on address range 2711loopw - infinite write loop on address range 2712mtest - simple RAM test 2713icache - enable or disable instruction cache 2714dcache - enable or disable data cache 2715reset - Perform RESET of the CPU 2716echo - echo args to console 2717version - print monitor version 2718help - print online help 2719? - alias for 'help' 2720 2721 2722Monitor Commands - Detailed Description: 2723======================================== 2724 2725TODO. 2726 2727For now: just type "help <command>". 2728 2729 2730Environment Variables: 2731====================== 2732 2733U-Boot supports user configuration using Environment Variables which 2734can be made persistent by saving to Flash memory. 2735 2736Environment Variables are set using "setenv", printed using 2737"printenv", and saved to Flash using "saveenv". Using "setenv" 2738without a value can be used to delete a variable from the 2739environment. As long as you don't save the environment you are 2740working with an in-memory copy. In case the Flash area containing the 2741environment is erased by accident, a default environment is provided. 2742 2743Some configuration options can be set using Environment Variables: 2744 2745 baudrate - see CONFIG_BAUDRATE 2746 2747 bootdelay - see CONFIG_BOOTDELAY 2748 2749 bootcmd - see CONFIG_BOOTCOMMAND 2750 2751 bootargs - Boot arguments when booting an RTOS image 2752 2753 bootfile - Name of the image to load with TFTP 2754 2755 bootm_low - Memory range available for image processing in the bootm 2756 command can be restricted. This variable is given as 2757 a hexadecimal number and defines lowest address allowed 2758 for use by the bootm command. See also "bootm_size" 2759 environment variable. Address defined by "bootm_low" is 2760 also the base of the initial memory mapping for the Linux 2761 kernel -- see the descripton of CFG_BOOTMAPSZ. 2762 2763 bootm_size - Memory range available for image processing in the bootm 2764 command can be restricted. This variable is given as 2765 a hexadecimal number and defines the size of the region 2766 allowed for use by the bootm command. See also "bootm_low" 2767 environment variable. 2768 2769 autoload - if set to "no" (any string beginning with 'n'), 2770 "bootp" will just load perform a lookup of the 2771 configuration from the BOOTP server, but not try to 2772 load any image using TFTP 2773 2774 autoscript - if set to "yes" commands like "loadb", "loady", 2775 "bootp", "tftpb", "rarpboot" and "nfs" will attempt 2776 to automatically run script images (by internally 2777 calling "autoscript"). 2778 2779 autoscript_uname - if script image is in a format (FIT) this 2780 variable is used to get script subimage unit name. 2781 2782 autostart - if set to "yes", an image loaded using the "bootp", 2783 "rarpboot", "tftpboot" or "diskboot" commands will 2784 be automatically started (by internally calling 2785 "bootm") 2786 2787 If set to "no", a standalone image passed to the 2788 "bootm" command will be copied to the load address 2789 (and eventually uncompressed), but NOT be started. 2790 This can be used to load and uncompress arbitrary 2791 data. 2792 2793 i2cfast - (PPC405GP|PPC405EP only) 2794 if set to 'y' configures Linux I2C driver for fast 2795 mode (400kHZ). This environment variable is used in 2796 initialization code. So, for changes to be effective 2797 it must be saved and board must be reset. 2798 2799 initrd_high - restrict positioning of initrd images: 2800 If this variable is not set, initrd images will be 2801 copied to the highest possible address in RAM; this 2802 is usually what you want since it allows for 2803 maximum initrd size. If for some reason you want to 2804 make sure that the initrd image is loaded below the 2805 CFG_BOOTMAPSZ limit, you can set this environment 2806 variable to a value of "no" or "off" or "0". 2807 Alternatively, you can set it to a maximum upper 2808 address to use (U-Boot will still check that it 2809 does not overwrite the U-Boot stack and data). 2810 2811 For instance, when you have a system with 16 MB 2812 RAM, and want to reserve 4 MB from use by Linux, 2813 you can do this by adding "mem=12M" to the value of 2814 the "bootargs" variable. However, now you must make 2815 sure that the initrd image is placed in the first 2816 12 MB as well - this can be done with 2817 2818 setenv initrd_high 00c00000 2819 2820 If you set initrd_high to 0xFFFFFFFF, this is an 2821 indication to U-Boot that all addresses are legal 2822 for the Linux kernel, including addresses in flash 2823 memory. In this case U-Boot will NOT COPY the 2824 ramdisk at all. This may be useful to reduce the 2825 boot time on your system, but requires that this 2826 feature is supported by your Linux kernel. 2827 2828 ipaddr - IP address; needed for tftpboot command 2829 2830 loadaddr - Default load address for commands like "bootp", 2831 "rarpboot", "tftpboot", "loadb" or "diskboot" 2832 2833 loads_echo - see CONFIG_LOADS_ECHO 2834 2835 serverip - TFTP server IP address; needed for tftpboot command 2836 2837 bootretry - see CONFIG_BOOT_RETRY_TIME 2838 2839 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR 2840 2841 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR 2842 2843 ethprime - When CONFIG_NET_MULTI is enabled controls which 2844 interface is used first. 2845 2846 ethact - When CONFIG_NET_MULTI is enabled controls which 2847 interface is currently active. For example you 2848 can do the following 2849 2850 => setenv ethact FEC ETHERNET 2851 => ping 192.168.0.1 # traffic sent on FEC ETHERNET 2852 => setenv ethact SCC ETHERNET 2853 => ping 10.0.0.1 # traffic sent on SCC ETHERNET 2854 2855 ethrotate - When set to "no" U-Boot does not go through all 2856 available network interfaces. 2857 It just stays at the currently selected interface. 2858 2859 netretry - When set to "no" each network operation will 2860 either succeed or fail without retrying. 2861 When set to "once" the network operation will 2862 fail when all the available network interfaces 2863 are tried once without success. 2864 Useful on scripts which control the retry operation 2865 themselves. 2866 2867 npe_ucode - see CONFIG_IXP4XX_NPE_EXT_UCOD 2868 if set load address for the npe microcode 2869 2870 tftpsrcport - If this is set, the value is used for TFTP's 2871 UDP source port. 2872 2873 tftpdstport - If this is set, the value is used for TFTP's UDP 2874 destination port instead of the Well Know Port 69. 2875 2876 vlan - When set to a value < 4095 the traffic over 2877 ethernet is encapsulated/received over 802.1q 2878 VLAN tagged frames. 2879 2880The following environment variables may be used and automatically 2881updated by the network boot commands ("bootp" and "rarpboot"), 2882depending the information provided by your boot server: 2883 2884 bootfile - see above 2885 dnsip - IP address of your Domain Name Server 2886 dnsip2 - IP address of your secondary Domain Name Server 2887 gatewayip - IP address of the Gateway (Router) to use 2888 hostname - Target hostname 2889 ipaddr - see above 2890 netmask - Subnet Mask 2891 rootpath - Pathname of the root filesystem on the NFS server 2892 serverip - see above 2893 2894 2895There are two special Environment Variables: 2896 2897 serial# - contains hardware identification information such 2898 as type string and/or serial number 2899 ethaddr - Ethernet address 2900 2901These variables can be set only once (usually during manufacturing of 2902the board). U-Boot refuses to delete or overwrite these variables 2903once they have been set once. 2904 2905 2906Further special Environment Variables: 2907 2908 ver - Contains the U-Boot version string as printed 2909 with the "version" command. This variable is 2910 readonly (see CONFIG_VERSION_VARIABLE). 2911 2912 2913Please note that changes to some configuration parameters may take 2914only effect after the next boot (yes, that's just like Windoze :-). 2915 2916 2917Command Line Parsing: 2918===================== 2919 2920There are two different command line parsers available with U-Boot: 2921the old "simple" one, and the much more powerful "hush" shell: 2922 2923Old, simple command line parser: 2924-------------------------------- 2925 2926- supports environment variables (through setenv / saveenv commands) 2927- several commands on one line, separated by ';' 2928- variable substitution using "... ${name} ..." syntax 2929- special characters ('$', ';') can be escaped by prefixing with '\', 2930 for example: 2931 setenv bootcmd bootm \${address} 2932- You can also escape text by enclosing in single apostrophes, for example: 2933 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off' 2934 2935Hush shell: 2936----------- 2937 2938- similar to Bourne shell, with control structures like 2939 if...then...else...fi, for...do...done; while...do...done, 2940 until...do...done, ... 2941- supports environment ("global") variables (through setenv / saveenv 2942 commands) and local shell variables (through standard shell syntax 2943 "name=value"); only environment variables can be used with "run" 2944 command 2945 2946General rules: 2947-------------- 2948 2949(1) If a command line (or an environment variable executed by a "run" 2950 command) contains several commands separated by semicolon, and 2951 one of these commands fails, then the remaining commands will be 2952 executed anyway. 2953 2954(2) If you execute several variables with one call to run (i. e. 2955 calling run with a list af variables as arguments), any failing 2956 command will cause "run" to terminate, i. e. the remaining 2957 variables are not executed. 2958 2959Note for Redundant Ethernet Interfaces: 2960======================================= 2961 2962Some boards come with redundant ethernet interfaces; U-Boot supports 2963such configurations and is capable of automatic selection of a 2964"working" interface when needed. MAC assignment works as follows: 2965 2966Network interfaces are numbered eth0, eth1, eth2, ... Corresponding 2967MAC addresses can be stored in the environment as "ethaddr" (=>eth0), 2968"eth1addr" (=>eth1), "eth2addr", ... 2969 2970If the network interface stores some valid MAC address (for instance 2971in SROM), this is used as default address if there is NO correspon- 2972ding setting in the environment; if the corresponding environment 2973variable is set, this overrides the settings in the card; that means: 2974 2975o If the SROM has a valid MAC address, and there is no address in the 2976 environment, the SROM's address is used. 2977 2978o If there is no valid address in the SROM, and a definition in the 2979 environment exists, then the value from the environment variable is 2980 used. 2981 2982o If both the SROM and the environment contain a MAC address, and 2983 both addresses are the same, this MAC address is used. 2984 2985o If both the SROM and the environment contain a MAC address, and the 2986 addresses differ, the value from the environment is used and a 2987 warning is printed. 2988 2989o If neither SROM nor the environment contain a MAC address, an error 2990 is raised. 2991 2992 2993Image Formats: 2994============== 2995 2996U-Boot is capable of booting (and performing other auxiliary operations on) 2997images in two formats: 2998 2999New uImage format (FIT) 3000----------------------- 3001 3002Flexible and powerful format based on Flattened Image Tree -- FIT (similar 3003to Flattened Device Tree). It allows the use of images with multiple 3004components (several kernels, ramdisks, etc.), with contents protected by 3005SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory. 3006 3007 3008Old uImage format 3009----------------- 3010 3011Old image format is based on binary files which can be basically anything, 3012preceded by a special header; see the definitions in include/image.h for 3013details; basically, the header defines the following image properties: 3014 3015* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD, 3016 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks, 3017 LynxOS, pSOS, QNX, RTEMS, ARTOS; 3018 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, ARTOS, LynxOS). 3019* Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86, 3020 IA64, MIPS, NIOS, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit; 3021 Currently supported: ARM, AVR32, Intel x86, MIPS, NIOS, PowerPC). 3022* Compression Type (uncompressed, gzip, bzip2) 3023* Load Address 3024* Entry Point 3025* Image Name 3026* Image Timestamp 3027 3028The header is marked by a special Magic Number, and both the header 3029and the data portions of the image are secured against corruption by 3030CRC32 checksums. 3031 3032 3033Linux Support: 3034============== 3035 3036Although U-Boot should support any OS or standalone application 3037easily, the main focus has always been on Linux during the design of 3038U-Boot. 3039 3040U-Boot includes many features that so far have been part of some 3041special "boot loader" code within the Linux kernel. Also, any 3042"initrd" images to be used are no longer part of one big Linux image; 3043instead, kernel and "initrd" are separate images. This implementation 3044serves several purposes: 3045 3046- the same features can be used for other OS or standalone 3047 applications (for instance: using compressed images to reduce the 3048 Flash memory footprint) 3049 3050- it becomes much easier to port new Linux kernel versions because 3051 lots of low-level, hardware dependent stuff are done by U-Boot 3052 3053- the same Linux kernel image can now be used with different "initrd" 3054 images; of course this also means that different kernel images can 3055 be run with the same "initrd". This makes testing easier (you don't 3056 have to build a new "zImage.initrd" Linux image when you just 3057 change a file in your "initrd"). Also, a field-upgrade of the 3058 software is easier now. 3059 3060 3061Linux HOWTO: 3062============ 3063 3064Porting Linux to U-Boot based systems: 3065--------------------------------------- 3066 3067U-Boot cannot save you from doing all the necessary modifications to 3068configure the Linux device drivers for use with your target hardware 3069(no, we don't intend to provide a full virtual machine interface to 3070Linux :-). 3071 3072But now you can ignore ALL boot loader code (in arch/ppc/mbxboot). 3073 3074Just make sure your machine specific header file (for instance 3075include/asm-ppc/tqm8xx.h) includes the same definition of the Board 3076Information structure as we define in include/u-boot.h, and make 3077sure that your definition of IMAP_ADDR uses the same value as your 3078U-Boot configuration in CFG_IMMR. 3079 3080 3081Configuring the Linux kernel: 3082----------------------------- 3083 3084No specific requirements for U-Boot. Make sure you have some root 3085device (initial ramdisk, NFS) for your target system. 3086 3087 3088Building a Linux Image: 3089----------------------- 3090 3091With U-Boot, "normal" build targets like "zImage" or "bzImage" are 3092not used. If you use recent kernel source, a new build target 3093"uImage" will exist which automatically builds an image usable by 3094U-Boot. Most older kernels also have support for a "pImage" target, 3095which was introduced for our predecessor project PPCBoot and uses a 3096100% compatible format. 3097 3098Example: 3099 3100 make TQM850L_config 3101 make oldconfig 3102 make dep 3103 make uImage 3104 3105The "uImage" build target uses a special tool (in 'tools/mkimage') to 3106encapsulate a compressed Linux kernel image with header information, 3107CRC32 checksum etc. for use with U-Boot. This is what we are doing: 3108 3109* build a standard "vmlinux" kernel image (in ELF binary format): 3110 3111* convert the kernel into a raw binary image: 3112 3113 ${CROSS_COMPILE}-objcopy -O binary \ 3114 -R .note -R .comment \ 3115 -S vmlinux linux.bin 3116 3117* compress the binary image: 3118 3119 gzip -9 linux.bin 3120 3121* package compressed binary image for U-Boot: 3122 3123 mkimage -A ppc -O linux -T kernel -C gzip \ 3124 -a 0 -e 0 -n "Linux Kernel Image" \ 3125 -d linux.bin.gz uImage 3126 3127 3128The "mkimage" tool can also be used to create ramdisk images for use 3129with U-Boot, either separated from the Linux kernel image, or 3130combined into one file. "mkimage" encapsulates the images with a 64 3131byte header containing information about target architecture, 3132operating system, image type, compression method, entry points, time 3133stamp, CRC32 checksums, etc. 3134 3135"mkimage" can be called in two ways: to verify existing images and 3136print the header information, or to build new images. 3137 3138In the first form (with "-l" option) mkimage lists the information 3139contained in the header of an existing U-Boot image; this includes 3140checksum verification: 3141 3142 tools/mkimage -l image 3143 -l ==> list image header information 3144 3145The second form (with "-d" option) is used to build a U-Boot image 3146from a "data file" which is used as image payload: 3147 3148 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \ 3149 -n name -d data_file image 3150 -A ==> set architecture to 'arch' 3151 -O ==> set operating system to 'os' 3152 -T ==> set image type to 'type' 3153 -C ==> set compression type 'comp' 3154 -a ==> set load address to 'addr' (hex) 3155 -e ==> set entry point to 'ep' (hex) 3156 -n ==> set image name to 'name' 3157 -d ==> use image data from 'datafile' 3158 3159Right now, all Linux kernels for PowerPC systems use the same load 3160address (0x00000000), but the entry point address depends on the 3161kernel version: 3162 3163- 2.2.x kernels have the entry point at 0x0000000C, 3164- 2.3.x and later kernels have the entry point at 0x00000000. 3165 3166So a typical call to build a U-Boot image would read: 3167 3168 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 3169 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \ 3170 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz \ 3171 > examples/uImage.TQM850L 3172 Image Name: 2.4.4 kernel for TQM850L 3173 Created: Wed Jul 19 02:34:59 2000 3174 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3175 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 3176 Load Address: 0x00000000 3177 Entry Point: 0x00000000 3178 3179To verify the contents of the image (or check for corruption): 3180 3181 -> tools/mkimage -l examples/uImage.TQM850L 3182 Image Name: 2.4.4 kernel for TQM850L 3183 Created: Wed Jul 19 02:34:59 2000 3184 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3185 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 3186 Load Address: 0x00000000 3187 Entry Point: 0x00000000 3188 3189NOTE: for embedded systems where boot time is critical you can trade 3190speed for memory and install an UNCOMPRESSED image instead: this 3191needs more space in Flash, but boots much faster since it does not 3192need to be uncompressed: 3193 3194 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz 3195 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 3196 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \ 3197 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux \ 3198 > examples/uImage.TQM850L-uncompressed 3199 Image Name: 2.4.4 kernel for TQM850L 3200 Created: Wed Jul 19 02:34:59 2000 3201 Image Type: PowerPC Linux Kernel Image (uncompressed) 3202 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB 3203 Load Address: 0x00000000 3204 Entry Point: 0x00000000 3205 3206 3207Similar you can build U-Boot images from a 'ramdisk.image.gz' file 3208when your kernel is intended to use an initial ramdisk: 3209 3210 -> tools/mkimage -n 'Simple Ramdisk Image' \ 3211 > -A ppc -O linux -T ramdisk -C gzip \ 3212 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd 3213 Image Name: Simple Ramdisk Image 3214 Created: Wed Jan 12 14:01:50 2000 3215 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 3216 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB 3217 Load Address: 0x00000000 3218 Entry Point: 0x00000000 3219 3220 3221Installing a Linux Image: 3222------------------------- 3223 3224To downloading a U-Boot image over the serial (console) interface, 3225you must convert the image to S-Record format: 3226 3227 objcopy -I binary -O srec examples/image examples/image.srec 3228 3229The 'objcopy' does not understand the information in the U-Boot 3230image header, so the resulting S-Record file will be relative to 3231address 0x00000000. To load it to a given address, you need to 3232specify the target address as 'offset' parameter with the 'loads' 3233command. 3234 3235Example: install the image to address 0x40100000 (which on the 3236TQM8xxL is in the first Flash bank): 3237 3238 => erase 40100000 401FFFFF 3239 3240 .......... done 3241 Erased 8 sectors 3242 3243 => loads 40100000 3244 ## Ready for S-Record download ... 3245 ~>examples/image.srec 3246 1 2 3 4 5 6 7 8 9 10 11 12 13 ... 3247 ... 3248 15989 15990 15991 15992 3249 [file transfer complete] 3250 [connected] 3251 ## Start Addr = 0x00000000 3252 3253 3254You can check the success of the download using the 'iminfo' command; 3255this includes a checksum verification so you can be sure no data 3256corruption happened: 3257 3258 => imi 40100000 3259 3260 ## Checking Image at 40100000 ... 3261 Image Name: 2.2.13 for initrd on TQM850L 3262 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3263 Data Size: 335725 Bytes = 327 kB = 0 MB 3264 Load Address: 00000000 3265 Entry Point: 0000000c 3266 Verifying Checksum ... OK 3267 3268 3269Boot Linux: 3270----------- 3271 3272The "bootm" command is used to boot an application that is stored in 3273memory (RAM or Flash). In case of a Linux kernel image, the contents 3274of the "bootargs" environment variable is passed to the kernel as 3275parameters. You can check and modify this variable using the 3276"printenv" and "setenv" commands: 3277 3278 3279 => printenv bootargs 3280 bootargs=root=/dev/ram 3281 3282 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 3283 3284 => printenv bootargs 3285 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 3286 3287 => bootm 40020000 3288 ## Booting Linux kernel at 40020000 ... 3289 Image Name: 2.2.13 for NFS on TQM850L 3290 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3291 Data Size: 381681 Bytes = 372 kB = 0 MB 3292 Load Address: 00000000 3293 Entry Point: 0000000c 3294 Verifying Checksum ... OK 3295 Uncompressing Kernel Image ... OK 3296 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 3297 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 3298 time_init: decrementer frequency = 187500000/60 3299 Calibrating delay loop... 49.77 BogoMIPS 3300 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000] 3301 ... 3302 3303If you want to boot a Linux kernel with initial ram disk, you pass 3304the memory addresses of both the kernel and the initrd image (PPBCOOT 3305format!) to the "bootm" command: 3306 3307 => imi 40100000 40200000 3308 3309 ## Checking Image at 40100000 ... 3310 Image Name: 2.2.13 for initrd on TQM850L 3311 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3312 Data Size: 335725 Bytes = 327 kB = 0 MB 3313 Load Address: 00000000 3314 Entry Point: 0000000c 3315 Verifying Checksum ... OK 3316 3317 ## Checking Image at 40200000 ... 3318 Image Name: Simple Ramdisk Image 3319 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 3320 Data Size: 566530 Bytes = 553 kB = 0 MB 3321 Load Address: 00000000 3322 Entry Point: 00000000 3323 Verifying Checksum ... OK 3324 3325 => bootm 40100000 40200000 3326 ## Booting Linux kernel at 40100000 ... 3327 Image Name: 2.2.13 for initrd on TQM850L 3328 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3329 Data Size: 335725 Bytes = 327 kB = 0 MB 3330 Load Address: 00000000 3331 Entry Point: 0000000c 3332 Verifying Checksum ... OK 3333 Uncompressing Kernel Image ... OK 3334 ## Loading RAMDisk Image at 40200000 ... 3335 Image Name: Simple Ramdisk Image 3336 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 3337 Data Size: 566530 Bytes = 553 kB = 0 MB 3338 Load Address: 00000000 3339 Entry Point: 00000000 3340 Verifying Checksum ... OK 3341 Loading Ramdisk ... OK 3342 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 3343 Boot arguments: root=/dev/ram 3344 time_init: decrementer frequency = 187500000/60 3345 Calibrating delay loop... 49.77 BogoMIPS 3346 ... 3347 RAMDISK: Compressed image found at block 0 3348 VFS: Mounted root (ext2 filesystem). 3349 3350 bash# 3351 3352Boot Linux and pass a flat device tree: 3353----------- 3354 3355First, U-Boot must be compiled with the appropriate defines. See the section 3356titled "Linux Kernel Interface" above for a more in depth explanation. The 3357following is an example of how to start a kernel and pass an updated 3358flat device tree: 3359 3360=> print oftaddr 3361oftaddr=0x300000 3362=> print oft 3363oft=oftrees/mpc8540ads.dtb 3364=> tftp $oftaddr $oft 3365Speed: 1000, full duplex 3366Using TSEC0 device 3367TFTP from server 192.168.1.1; our IP address is 192.168.1.101 3368Filename 'oftrees/mpc8540ads.dtb'. 3369Load address: 0x300000 3370Loading: # 3371done 3372Bytes transferred = 4106 (100a hex) 3373=> tftp $loadaddr $bootfile 3374Speed: 1000, full duplex 3375Using TSEC0 device 3376TFTP from server 192.168.1.1; our IP address is 192.168.1.2 3377Filename 'uImage'. 3378Load address: 0x200000 3379Loading:############ 3380done 3381Bytes transferred = 1029407 (fb51f hex) 3382=> print loadaddr 3383loadaddr=200000 3384=> print oftaddr 3385oftaddr=0x300000 3386=> bootm $loadaddr - $oftaddr 3387## Booting image at 00200000 ... 3388 Image Name: Linux-2.6.17-dirty 3389 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3390 Data Size: 1029343 Bytes = 1005.2 kB 3391 Load Address: 00000000 3392 Entry Point: 00000000 3393 Verifying Checksum ... OK 3394 Uncompressing Kernel Image ... OK 3395Booting using flat device tree at 0x300000 3396Using MPC85xx ADS machine description 3397Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb 3398[snip] 3399 3400 3401More About U-Boot Image Types: 3402------------------------------ 3403 3404U-Boot supports the following image types: 3405 3406 "Standalone Programs" are directly runnable in the environment 3407 provided by U-Boot; it is expected that (if they behave 3408 well) you can continue to work in U-Boot after return from 3409 the Standalone Program. 3410 "OS Kernel Images" are usually images of some Embedded OS which 3411 will take over control completely. Usually these programs 3412 will install their own set of exception handlers, device 3413 drivers, set up the MMU, etc. - this means, that you cannot 3414 expect to re-enter U-Boot except by resetting the CPU. 3415 "RAMDisk Images" are more or less just data blocks, and their 3416 parameters (address, size) are passed to an OS kernel that is 3417 being started. 3418 "Multi-File Images" contain several images, typically an OS 3419 (Linux) kernel image and one or more data images like 3420 RAMDisks. This construct is useful for instance when you want 3421 to boot over the network using BOOTP etc., where the boot 3422 server provides just a single image file, but you want to get 3423 for instance an OS kernel and a RAMDisk image. 3424 3425 "Multi-File Images" start with a list of image sizes, each 3426 image size (in bytes) specified by an "uint32_t" in network 3427 byte order. This list is terminated by an "(uint32_t)0". 3428 Immediately after the terminating 0 follow the images, one by 3429 one, all aligned on "uint32_t" boundaries (size rounded up to 3430 a multiple of 4 bytes). 3431 3432 "Firmware Images" are binary images containing firmware (like 3433 U-Boot or FPGA images) which usually will be programmed to 3434 flash memory. 3435 3436 "Script files" are command sequences that will be executed by 3437 U-Boot's command interpreter; this feature is especially 3438 useful when you configure U-Boot to use a real shell (hush) 3439 as command interpreter. 3440 3441 3442Standalone HOWTO: 3443================= 3444 3445One of the features of U-Boot is that you can dynamically load and 3446run "standalone" applications, which can use some resources of 3447U-Boot like console I/O functions or interrupt services. 3448 3449Two simple examples are included with the sources: 3450 3451"Hello World" Demo: 3452------------------- 3453 3454'examples/hello_world.c' contains a small "Hello World" Demo 3455application; it is automatically compiled when you build U-Boot. 3456It's configured to run at address 0x00040004, so you can play with it 3457like that: 3458 3459 => loads 3460 ## Ready for S-Record download ... 3461 ~>examples/hello_world.srec 3462 1 2 3 4 5 6 7 8 9 10 11 ... 3463 [file transfer complete] 3464 [connected] 3465 ## Start Addr = 0x00040004 3466 3467 => go 40004 Hello World! This is a test. 3468 ## Starting application at 0x00040004 ... 3469 Hello World 3470 argc = 7 3471 argv[0] = "40004" 3472 argv[1] = "Hello" 3473 argv[2] = "World!" 3474 argv[3] = "This" 3475 argv[4] = "is" 3476 argv[5] = "a" 3477 argv[6] = "test." 3478 argv[7] = "<NULL>" 3479 Hit any key to exit ... 3480 3481 ## Application terminated, rc = 0x0 3482 3483Another example, which demonstrates how to register a CPM interrupt 3484handler with the U-Boot code, can be found in 'examples/timer.c'. 3485Here, a CPM timer is set up to generate an interrupt every second. 3486The interrupt service routine is trivial, just printing a '.' 3487character, but this is just a demo program. The application can be 3488controlled by the following keys: 3489 3490 ? - print current values og the CPM Timer registers 3491 b - enable interrupts and start timer 3492 e - stop timer and disable interrupts 3493 q - quit application 3494 3495 => loads 3496 ## Ready for S-Record download ... 3497 ~>examples/timer.srec 3498 1 2 3 4 5 6 7 8 9 10 11 ... 3499 [file transfer complete] 3500 [connected] 3501 ## Start Addr = 0x00040004 3502 3503 => go 40004 3504 ## Starting application at 0x00040004 ... 3505 TIMERS=0xfff00980 3506 Using timer 1 3507 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0 3508 3509Hit 'b': 3510 [q, b, e, ?] Set interval 1000000 us 3511 Enabling timer 3512Hit '?': 3513 [q, b, e, ?] ........ 3514 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0 3515Hit '?': 3516 [q, b, e, ?] . 3517 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0 3518Hit '?': 3519 [q, b, e, ?] . 3520 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0 3521Hit '?': 3522 [q, b, e, ?] . 3523 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0 3524Hit 'e': 3525 [q, b, e, ?] ...Stopping timer 3526Hit 'q': 3527 [q, b, e, ?] ## Application terminated, rc = 0x0 3528 3529 3530Minicom warning: 3531================ 3532 3533Over time, many people have reported problems when trying to use the 3534"minicom" terminal emulation program for serial download. I (wd) 3535consider minicom to be broken, and recommend not to use it. Under 3536Unix, I recommend to use C-Kermit for general purpose use (and 3537especially for kermit binary protocol download ("loadb" command), and 3538use "cu" for S-Record download ("loads" command). 3539 3540Nevertheless, if you absolutely want to use it try adding this 3541configuration to your "File transfer protocols" section: 3542 3543 Name Program Name U/D FullScr IO-Red. Multi 3544 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N 3545 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N 3546 3547 3548NetBSD Notes: 3549============= 3550 3551Starting at version 0.9.2, U-Boot supports NetBSD both as host 3552(build U-Boot) and target system (boots NetBSD/mpc8xx). 3553 3554Building requires a cross environment; it is known to work on 3555NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also 3556need gmake since the Makefiles are not compatible with BSD make). 3557Note that the cross-powerpc package does not install include files; 3558attempting to build U-Boot will fail because <machine/ansi.h> is 3559missing. This file has to be installed and patched manually: 3560 3561 # cd /usr/pkg/cross/powerpc-netbsd/include 3562 # mkdir powerpc 3563 # ln -s powerpc machine 3564 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h 3565 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST 3566 3567Native builds *don't* work due to incompatibilities between native 3568and U-Boot include files. 3569 3570Booting assumes that (the first part of) the image booted is a 3571stage-2 loader which in turn loads and then invokes the kernel 3572proper. Loader sources will eventually appear in the NetBSD source 3573tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the 3574meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz 3575 3576 3577Implementation Internals: 3578========================= 3579 3580The following is not intended to be a complete description of every 3581implementation detail. However, it should help to understand the 3582inner workings of U-Boot and make it easier to port it to custom 3583hardware. 3584 3585 3586Initial Stack, Global Data: 3587--------------------------- 3588 3589The implementation of U-Boot is complicated by the fact that U-Boot 3590starts running out of ROM (flash memory), usually without access to 3591system RAM (because the memory controller is not initialized yet). 3592This means that we don't have writable Data or BSS segments, and BSS 3593is not initialized as zero. To be able to get a C environment working 3594at all, we have to allocate at least a minimal stack. Implementation 3595options for this are defined and restricted by the CPU used: Some CPU 3596models provide on-chip memory (like the IMMR area on MPC8xx and 3597MPC826x processors), on others (parts of) the data cache can be 3598locked as (mis-) used as memory, etc. 3599 3600 Chris Hallinan posted a good summary of these issues to the 3601 u-boot-users mailing list: 3602 3603 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)? 3604 From: "Chris Hallinan" <clh@net1plus.com> 3605 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET) 3606 ... 3607 3608 Correct me if I'm wrong, folks, but the way I understand it 3609 is this: Using DCACHE as initial RAM for Stack, etc, does not 3610 require any physical RAM backing up the cache. The cleverness 3611 is that the cache is being used as a temporary supply of 3612 necessary storage before the SDRAM controller is setup. It's 3613 beyond the scope of this list to expain the details, but you 3614 can see how this works by studying the cache architecture and 3615 operation in the architecture and processor-specific manuals. 3616 3617 OCM is On Chip Memory, which I believe the 405GP has 4K. It 3618 is another option for the system designer to use as an 3619 initial stack/ram area prior to SDRAM being available. Either 3620 option should work for you. Using CS 4 should be fine if your 3621 board designers haven't used it for something that would 3622 cause you grief during the initial boot! It is frequently not 3623 used. 3624 3625 CFG_INIT_RAM_ADDR should be somewhere that won't interfere 3626 with your processor/board/system design. The default value 3627 you will find in any recent u-boot distribution in 3628 walnut.h should work for you. I'd set it to a value larger 3629 than your SDRAM module. If you have a 64MB SDRAM module, set 3630 it above 400_0000. Just make sure your board has no resources 3631 that are supposed to respond to that address! That code in 3632 start.S has been around a while and should work as is when 3633 you get the config right. 3634 3635 -Chris Hallinan 3636 DS4.COM, Inc. 3637 3638It is essential to remember this, since it has some impact on the C 3639code for the initialization procedures: 3640 3641* Initialized global data (data segment) is read-only. Do not attempt 3642 to write it. 3643 3644* Do not use any unitialized global data (or implicitely initialized 3645 as zero data - BSS segment) at all - this is undefined, initiali- 3646 zation is performed later (when relocating to RAM). 3647 3648* Stack space is very limited. Avoid big data buffers or things like 3649 that. 3650 3651Having only the stack as writable memory limits means we cannot use 3652normal global data to share information beween the code. But it 3653turned out that the implementation of U-Boot can be greatly 3654simplified by making a global data structure (gd_t) available to all 3655functions. We could pass a pointer to this data as argument to _all_ 3656functions, but this would bloat the code. Instead we use a feature of 3657the GCC compiler (Global Register Variables) to share the data: we 3658place a pointer (gd) to the global data into a register which we 3659reserve for this purpose. 3660 3661When choosing a register for such a purpose we are restricted by the 3662relevant (E)ABI specifications for the current architecture, and by 3663GCC's implementation. 3664 3665For PowerPC, the following registers have specific use: 3666 R1: stack pointer 3667 R2: reserved for system use 3668 R3-R4: parameter passing and return values 3669 R5-R10: parameter passing 3670 R13: small data area pointer 3671 R30: GOT pointer 3672 R31: frame pointer 3673 3674 (U-Boot also uses R14 as internal GOT pointer.) 3675 3676 ==> U-Boot will use R2 to hold a pointer to the global data 3677 3678 Note: on PPC, we could use a static initializer (since the 3679 address of the global data structure is known at compile time), 3680 but it turned out that reserving a register results in somewhat 3681 smaller code - although the code savings are not that big (on 3682 average for all boards 752 bytes for the whole U-Boot image, 3683 624 text + 127 data). 3684 3685On Blackfin, the normal C ABI (except for P5) is followed as documented here: 3686 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface 3687 3688 ==> U-Boot will use P5 to hold a pointer to the global data 3689 3690On ARM, the following registers are used: 3691 3692 R0: function argument word/integer result 3693 R1-R3: function argument word 3694 R9: GOT pointer 3695 R10: stack limit (used only if stack checking if enabled) 3696 R11: argument (frame) pointer 3697 R12: temporary workspace 3698 R13: stack pointer 3699 R14: link register 3700 R15: program counter 3701 3702 ==> U-Boot will use R8 to hold a pointer to the global data 3703 3704NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope, 3705or current versions of GCC may "optimize" the code too much. 3706 3707Memory Management: 3708------------------ 3709 3710U-Boot runs in system state and uses physical addresses, i.e. the 3711MMU is not used either for address mapping nor for memory protection. 3712 3713The available memory is mapped to fixed addresses using the memory 3714controller. In this process, a contiguous block is formed for each 3715memory type (Flash, SDRAM, SRAM), even when it consists of several 3716physical memory banks. 3717 3718U-Boot is installed in the first 128 kB of the first Flash bank (on 3719TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After 3720booting and sizing and initializing DRAM, the code relocates itself 3721to the upper end of DRAM. Immediately below the U-Boot code some 3722memory is reserved for use by malloc() [see CFG_MALLOC_LEN 3723configuration setting]. Below that, a structure with global Board 3724Info data is placed, followed by the stack (growing downward). 3725 3726Additionally, some exception handler code is copied to the low 8 kB 3727of DRAM (0x00000000 ... 0x00001FFF). 3728 3729So a typical memory configuration with 16 MB of DRAM could look like 3730this: 3731 3732 0x0000 0000 Exception Vector code 3733 : 3734 0x0000 1FFF 3735 0x0000 2000 Free for Application Use 3736 : 3737 : 3738 3739 : 3740 : 3741 0x00FB FF20 Monitor Stack (Growing downward) 3742 0x00FB FFAC Board Info Data and permanent copy of global data 3743 0x00FC 0000 Malloc Arena 3744 : 3745 0x00FD FFFF 3746 0x00FE 0000 RAM Copy of Monitor Code 3747 ... eventually: LCD or video framebuffer 3748 ... eventually: pRAM (Protected RAM - unchanged by reset) 3749 0x00FF FFFF [End of RAM] 3750 3751 3752System Initialization: 3753---------------------- 3754 3755In the reset configuration, U-Boot starts at the reset entry point 3756(on most PowerPC systens at address 0x00000100). Because of the reset 3757configuration for CS0# this is a mirror of the onboard Flash memory. 3758To be able to re-map memory U-Boot then jumps to its link address. 3759To be able to implement the initialization code in C, a (small!) 3760initial stack is set up in the internal Dual Ported RAM (in case CPUs 3761which provide such a feature like MPC8xx or MPC8260), or in a locked 3762part of the data cache. After that, U-Boot initializes the CPU core, 3763the caches and the SIU. 3764 3765Next, all (potentially) available memory banks are mapped using a 3766preliminary mapping. For example, we put them on 512 MB boundaries 3767(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash 3768on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is 3769programmed for SDRAM access. Using the temporary configuration, a 3770simple memory test is run that determines the size of the SDRAM 3771banks. 3772 3773When there is more than one SDRAM bank, and the banks are of 3774different size, the largest is mapped first. For equal size, the first 3775bank (CS2#) is mapped first. The first mapping is always for address 37760x00000000, with any additional banks following immediately to create 3777contiguous memory starting from 0. 3778 3779Then, the monitor installs itself at the upper end of the SDRAM area 3780and allocates memory for use by malloc() and for the global Board 3781Info data; also, the exception vector code is copied to the low RAM 3782pages, and the final stack is set up. 3783 3784Only after this relocation will you have a "normal" C environment; 3785until that you are restricted in several ways, mostly because you are 3786running from ROM, and because the code will have to be relocated to a 3787new address in RAM. 3788 3789 3790U-Boot Porting Guide: 3791---------------------- 3792 3793[Based on messages by Jerry Van Baren in the U-Boot-Users mailing 3794list, October 2002] 3795 3796 3797int main (int argc, char *argv[]) 3798{ 3799 sighandler_t no_more_time; 3800 3801 signal (SIGALRM, no_more_time); 3802 alarm (PROJECT_DEADLINE - toSec (3 * WEEK)); 3803 3804 if (available_money > available_manpower) { 3805 pay consultant to port U-Boot; 3806 return 0; 3807 } 3808 3809 Download latest U-Boot source; 3810 3811 Subscribe to u-boot-users mailing list; 3812 3813 if (clueless) { 3814 email ("Hi, I am new to U-Boot, how do I get started?"); 3815 } 3816 3817 while (learning) { 3818 Read the README file in the top level directory; 3819 Read http://www.denx.de/twiki/bin/view/DULG/Manual ; 3820 Read the source, Luke; 3821 } 3822 3823 if (available_money > toLocalCurrency ($2500)) { 3824 Buy a BDI2000; 3825 } else { 3826 Add a lot of aggravation and time; 3827 } 3828 3829 Create your own board support subdirectory; 3830 3831 Create your own board config file; 3832 3833 while (!running) { 3834 do { 3835 Add / modify source code; 3836 } until (compiles); 3837 Debug; 3838 if (clueless) 3839 email ("Hi, I am having problems..."); 3840 } 3841 Send patch file to Wolfgang; 3842 3843 return 0; 3844} 3845 3846void no_more_time (int sig) 3847{ 3848 hire_a_guru(); 3849} 3850 3851 3852Coding Standards: 3853----------------- 3854 3855All contributions to U-Boot should conform to the Linux kernel 3856coding style; see the file "Documentation/CodingStyle" and the script 3857"scripts/Lindent" in your Linux kernel source directory. In sources 3858originating from U-Boot a style corresponding to "Lindent -pcs" (adding 3859spaces before parameters to function calls) is actually used. 3860 3861Source files originating from a different project (for example the 3862MTD subsystem) are generally exempt from these guidelines and are not 3863reformated to ease subsequent migration to newer versions of those 3864sources. 3865 3866Please note that U-Boot is implemented in C (and to some small parts in 3867Assembler); no C++ is used, so please do not use C++ style comments (//) 3868in your code. 3869 3870Please also stick to the following formatting rules: 3871- remove any trailing white space 3872- use TAB characters for indentation, not spaces 3873- make sure NOT to use DOS '\r\n' line feeds 3874- do not add more than 2 empty lines to source files 3875- do not add trailing empty lines to source files 3876 3877Submissions which do not conform to the standards may be returned 3878with a request to reformat the changes. 3879 3880 3881Submitting Patches: 3882------------------- 3883 3884Since the number of patches for U-Boot is growing, we need to 3885establish some rules. Submissions which do not conform to these rules 3886may be rejected, even when they contain important and valuable stuff. 3887 3888Patches shall be sent to the u-boot-users mailing list. 3889 3890Please see http://www.denx.de/wiki/UBoot/Patches for details. 3891 3892When you send a patch, please include the following information with 3893it: 3894 3895* For bug fixes: a description of the bug and how your patch fixes 3896 this bug. Please try to include a way of demonstrating that the 3897 patch actually fixes something. 3898 3899* For new features: a description of the feature and your 3900 implementation. 3901 3902* A CHANGELOG entry as plaintext (separate from the patch) 3903 3904* For major contributions, your entry to the CREDITS file 3905 3906* When you add support for a new board, don't forget to add this 3907 board to the MAKEALL script, too. 3908 3909* If your patch adds new configuration options, don't forget to 3910 document these in the README file. 3911 3912* The patch itself. If you are using git (which is *strongly* 3913 recommended) you can easily generate the patch using the 3914 "git-format-patch". If you then use "git-send-email" to send it to 3915 the U-Boot mailing list, you will avoid most of the common problems 3916 with some other mail clients. 3917 3918 If you cannot use git, use "diff -purN OLD NEW". If your version of 3919 diff does not support these options, then get the latest version of 3920 GNU diff. 3921 3922 The current directory when running this command shall be the parent 3923 directory of the U-Boot source tree (i. e. please make sure that 3924 your patch includes sufficient directory information for the 3925 affected files). 3926 3927 We prefer patches as plain text. MIME attachments are discouraged, 3928 and compressed attachments must not be used. 3929 3930* If one logical set of modifications affects or creates several 3931 files, all these changes shall be submitted in a SINGLE patch file. 3932 3933* Changesets that contain different, unrelated modifications shall be 3934 submitted as SEPARATE patches, one patch per changeset. 3935 3936 3937Notes: 3938 3939* Before sending the patch, run the MAKEALL script on your patched 3940 source tree and make sure that no errors or warnings are reported 3941 for any of the boards. 3942 3943* Keep your modifications to the necessary minimum: A patch 3944 containing several unrelated changes or arbitrary reformats will be 3945 returned with a request to re-formatting / split it. 3946 3947* If you modify existing code, make sure that your new code does not 3948 add to the memory footprint of the code ;-) Small is beautiful! 3949 When adding new features, these should compile conditionally only 3950 (using #ifdef), and the resulting code with the new feature 3951 disabled must not need more memory than the old code without your 3952 modification. 3953 3954* Remember that there is a size limit of 40 kB per message on the 3955 u-boot-users mailing list. Bigger patches will be moderated. If 3956 they are reasonable and not bigger than 100 kB, they will be 3957 acknowledged. Even bigger patches should be avoided. 3958