1# 2# (C) Copyright 2000 - 2013 3# Wolfgang Denk, DENX Software Engineering, wd@denx.de. 4# 5# SPDX-License-Identifier: GPL-2.0+ 6# 7 8Summary: 9======== 10 11This directory contains the source code for U-Boot, a boot loader for 12Embedded boards based on PowerPC, ARM, MIPS and several other 13processors, which can be installed in a boot ROM and used to 14initialize and test the hardware or to download and run application 15code. 16 17The development of U-Boot is closely related to Linux: some parts of 18the source code originate in the Linux source tree, we have some 19header files in common, and special provision has been made to 20support booting of Linux images. 21 22Some attention has been paid to make this software easily 23configurable and extendable. For instance, all monitor commands are 24implemented with the same call interface, so that it's very easy to 25add new commands. Also, instead of permanently adding rarely used 26code (for instance hardware test utilities) to the monitor, you can 27load and run it dynamically. 28 29 30Status: 31======= 32 33In general, all boards for which a configuration option exists in the 34Makefile have been tested to some extent and can be considered 35"working". In fact, many of them are used in production systems. 36 37In case of problems see the CHANGELOG file to find out who contributed 38the specific port. In addition, there are various MAINTAINERS files 39scattered throughout the U-Boot source identifying the people or 40companies responsible for various boards and subsystems. 41 42Note: As of August, 2010, there is no longer a CHANGELOG file in the 43actual U-Boot source tree; however, it can be created dynamically 44from the Git log using: 45 46 make CHANGELOG 47 48 49Where to get help: 50================== 51 52In case you have questions about, problems with or contributions for 53U-Boot, you should send a message to the U-Boot mailing list at 54<u-boot@lists.denx.de>. There is also an archive of previous traffic 55on the mailing list - please search the archive before asking FAQ's. 56Please see http://lists.denx.de/pipermail/u-boot and 57http://dir.gmane.org/gmane.comp.boot-loaders.u-boot 58 59 60Where to get source code: 61========================= 62 63The U-Boot source code is maintained in the Git repository at 64git://www.denx.de/git/u-boot.git ; you can browse it online at 65http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary 66 67The "snapshot" links on this page allow you to download tarballs of 68any version you might be interested in. Official releases are also 69available for FTP download from the ftp://ftp.denx.de/pub/u-boot/ 70directory. 71 72Pre-built (and tested) images are available from 73ftp://ftp.denx.de/pub/u-boot/images/ 74 75 76Where we come from: 77=================== 78 79- start from 8xxrom sources 80- create PPCBoot project (http://sourceforge.net/projects/ppcboot) 81- clean up code 82- make it easier to add custom boards 83- make it possible to add other [PowerPC] CPUs 84- extend functions, especially: 85 * Provide extended interface to Linux boot loader 86 * S-Record download 87 * network boot 88 * PCMCIA / CompactFlash / ATA disk / SCSI ... boot 89- create ARMBoot project (http://sourceforge.net/projects/armboot) 90- add other CPU families (starting with ARM) 91- create U-Boot project (http://sourceforge.net/projects/u-boot) 92- current project page: see http://www.denx.de/wiki/U-Boot 93 94 95Names and Spelling: 96=================== 97 98The "official" name of this project is "Das U-Boot". The spelling 99"U-Boot" shall be used in all written text (documentation, comments 100in source files etc.). Example: 101 102 This is the README file for the U-Boot project. 103 104File names etc. shall be based on the string "u-boot". Examples: 105 106 include/asm-ppc/u-boot.h 107 108 #include <asm/u-boot.h> 109 110Variable names, preprocessor constants etc. shall be either based on 111the string "u_boot" or on "U_BOOT". Example: 112 113 U_BOOT_VERSION u_boot_logo 114 IH_OS_U_BOOT u_boot_hush_start 115 116 117Versioning: 118=========== 119 120Starting with the release in October 2008, the names of the releases 121were changed from numerical release numbers without deeper meaning 122into a time stamp based numbering. Regular releases are identified by 123names consisting of the calendar year and month of the release date. 124Additional fields (if present) indicate release candidates or bug fix 125releases in "stable" maintenance trees. 126 127Examples: 128 U-Boot v2009.11 - Release November 2009 129 U-Boot v2009.11.1 - Release 1 in version November 2009 stable tree 130 U-Boot v2010.09-rc1 - Release candiate 1 for September 2010 release 131 132 133Directory Hierarchy: 134==================== 135 136/arch Architecture specific files 137 /arc Files generic to ARC architecture 138 /arm Files generic to ARM architecture 139 /avr32 Files generic to AVR32 architecture 140 /blackfin Files generic to Analog Devices Blackfin architecture 141 /m68k Files generic to m68k architecture 142 /microblaze Files generic to microblaze architecture 143 /mips Files generic to MIPS architecture 144 /nds32 Files generic to NDS32 architecture 145 /nios2 Files generic to Altera NIOS2 architecture 146 /openrisc Files generic to OpenRISC architecture 147 /powerpc Files generic to PowerPC architecture 148 /sandbox Files generic to HW-independent "sandbox" 149 /sh Files generic to SH architecture 150 /sparc Files generic to SPARC architecture 151 /x86 Files generic to x86 architecture 152/api Machine/arch independent API for external apps 153/board Board dependent files 154/common Misc architecture independent functions 155/configs Board default configuration files 156/disk Code for disk drive partition handling 157/doc Documentation (don't expect too much) 158/drivers Commonly used device drivers 159/dts Contains Makefile for building internal U-Boot fdt. 160/examples Example code for standalone applications, etc. 161/fs Filesystem code (cramfs, ext2, jffs2, etc.) 162/include Header Files 163/lib Library routines generic to all architectures 164/Licenses Various license files 165/net Networking code 166/post Power On Self Test 167/scripts Various build scripts and Makefiles 168/test Various unit test files 169/tools Tools to build S-Record or U-Boot images, etc. 170 171Software Configuration: 172======================= 173 174Configuration is usually done using C preprocessor defines; the 175rationale behind that is to avoid dead code whenever possible. 176 177There are two classes of configuration variables: 178 179* Configuration _OPTIONS_: 180 These are selectable by the user and have names beginning with 181 "CONFIG_". 182 183* Configuration _SETTINGS_: 184 These depend on the hardware etc. and should not be meddled with if 185 you don't know what you're doing; they have names beginning with 186 "CONFIG_SYS_". 187 188Previously, all configuration was done by hand, which involved creating 189symbolic links and editing configuration files manually. More recently, 190U-Boot has added the Kbuild infrastructure used by the Linux kernel, 191allowing you to use the "make menuconfig" command to configure your 192build. 193 194 195Selection of Processor Architecture and Board Type: 196--------------------------------------------------- 197 198For all supported boards there are ready-to-use default 199configurations available; just type "make <board_name>_defconfig". 200 201Example: For a TQM823L module type: 202 203 cd u-boot 204 make TQM823L_defconfig 205 206Note: If you're looking for the default configuration file for a board 207you're sure used to be there but is now missing, check the file 208doc/README.scrapyard for a list of no longer supported boards. 209 210Sandbox Environment: 211-------------------- 212 213U-Boot can be built natively to run on a Linux host using the 'sandbox' 214board. This allows feature development which is not board- or architecture- 215specific to be undertaken on a native platform. The sandbox is also used to 216run some of U-Boot's tests. 217 218See board/sandbox/README.sandbox for more details. 219 220 221Board Initialisation Flow: 222-------------------------- 223 224This is the intended start-up flow for boards. This should apply for both 225SPL and U-Boot proper (i.e. they both follow the same rules). 226 227Note: "SPL" stands for "Secondary Program Loader," which is explained in 228more detail later in this file. 229 230At present, SPL mostly uses a separate code path, but the function names 231and roles of each function are the same. Some boards or architectures 232may not conform to this. At least most ARM boards which use 233CONFIG_SPL_FRAMEWORK conform to this. 234 235Execution typically starts with an architecture-specific (and possibly 236CPU-specific) start.S file, such as: 237 238 - arch/arm/cpu/armv7/start.S 239 - arch/powerpc/cpu/mpc83xx/start.S 240 - arch/mips/cpu/start.S 241 242and so on. From there, three functions are called; the purpose and 243limitations of each of these functions are described below. 244 245lowlevel_init(): 246 - purpose: essential init to permit execution to reach board_init_f() 247 - no global_data or BSS 248 - there is no stack (ARMv7 may have one but it will soon be removed) 249 - must not set up SDRAM or use console 250 - must only do the bare minimum to allow execution to continue to 251 board_init_f() 252 - this is almost never needed 253 - return normally from this function 254 255board_init_f(): 256 - purpose: set up the machine ready for running board_init_r(): 257 i.e. SDRAM and serial UART 258 - global_data is available 259 - stack is in SRAM 260 - BSS is not available, so you cannot use global/static variables, 261 only stack variables and global_data 262 263 Non-SPL-specific notes: 264 - dram_init() is called to set up DRAM. If already done in SPL this 265 can do nothing 266 267 SPL-specific notes: 268 - you can override the entire board_init_f() function with your own 269 version as needed. 270 - preloader_console_init() can be called here in extremis 271 - should set up SDRAM, and anything needed to make the UART work 272 - these is no need to clear BSS, it will be done by crt0.S 273 - must return normally from this function (don't call board_init_r() 274 directly) 275 276Here the BSS is cleared. For SPL, if CONFIG_SPL_STACK_R is defined, then at 277this point the stack and global_data are relocated to below 278CONFIG_SPL_STACK_R_ADDR. For non-SPL, U-Boot is relocated to run at the top of 279memory. 280 281board_init_r(): 282 - purpose: main execution, common code 283 - global_data is available 284 - SDRAM is available 285 - BSS is available, all static/global variables can be used 286 - execution eventually continues to main_loop() 287 288 Non-SPL-specific notes: 289 - U-Boot is relocated to the top of memory and is now running from 290 there. 291 292 SPL-specific notes: 293 - stack is optionally in SDRAM, if CONFIG_SPL_STACK_R is defined and 294 CONFIG_SPL_STACK_R_ADDR points into SDRAM 295 - preloader_console_init() can be called here - typically this is 296 done by defining CONFIG_SPL_BOARD_INIT and then supplying a 297 spl_board_init() function containing this call 298 - loads U-Boot or (in falcon mode) Linux 299 300 301 302Configuration Options: 303---------------------- 304 305Configuration depends on the combination of board and CPU type; all 306such information is kept in a configuration file 307"include/configs/<board_name>.h". 308 309Example: For a TQM823L module, all configuration settings are in 310"include/configs/TQM823L.h". 311 312 313Many of the options are named exactly as the corresponding Linux 314kernel configuration options. The intention is to make it easier to 315build a config tool - later. 316 317 318The following options need to be configured: 319 320- CPU Type: Define exactly one, e.g. CONFIG_MPC85XX. 321 322- Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS. 323 324- CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined) 325 Define exactly one, e.g. CONFIG_ATSTK1002 326 327- CPU Module Type: (if CONFIG_COGENT is defined) 328 Define exactly one of 329 CONFIG_CMA286_60_OLD 330--- FIXME --- not tested yet: 331 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P, 332 CONFIG_CMA287_23, CONFIG_CMA287_50 333 334- Motherboard Type: (if CONFIG_COGENT is defined) 335 Define exactly one of 336 CONFIG_CMA101, CONFIG_CMA102 337 338- Motherboard I/O Modules: (if CONFIG_COGENT is defined) 339 Define one or more of 340 CONFIG_CMA302 341 342- Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined) 343 Define one or more of 344 CONFIG_LCD_HEARTBEAT - update a character position on 345 the LCD display every second with 346 a "rotator" |\-/|\-/ 347 348- Marvell Family Member 349 CONFIG_SYS_MVFS - define it if you want to enable 350 multiple fs option at one time 351 for marvell soc family 352 353- 8xx CPU Options: (if using an MPC8xx CPU) 354 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if 355 get_gclk_freq() cannot work 356 e.g. if there is no 32KHz 357 reference PIT/RTC clock 358 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK 359 or XTAL/EXTAL) 360 361- 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU): 362 CONFIG_SYS_8xx_CPUCLK_MIN 363 CONFIG_SYS_8xx_CPUCLK_MAX 364 CONFIG_8xx_CPUCLK_DEFAULT 365 See doc/README.MPC866 366 367 CONFIG_SYS_MEASURE_CPUCLK 368 369 Define this to measure the actual CPU clock instead 370 of relying on the correctness of the configured 371 values. Mostly useful for board bringup to make sure 372 the PLL is locked at the intended frequency. Note 373 that this requires a (stable) reference clock (32 kHz 374 RTC clock or CONFIG_SYS_8XX_XIN) 375 376 CONFIG_SYS_DELAYED_ICACHE 377 378 Define this option if you want to enable the 379 ICache only when Code runs from RAM. 380 381- 85xx CPU Options: 382 CONFIG_SYS_PPC64 383 384 Specifies that the core is a 64-bit PowerPC implementation (implements 385 the "64" category of the Power ISA). This is necessary for ePAPR 386 compliance, among other possible reasons. 387 388 CONFIG_SYS_FSL_TBCLK_DIV 389 390 Defines the core time base clock divider ratio compared to the 391 system clock. On most PQ3 devices this is 8, on newer QorIQ 392 devices it can be 16 or 32. The ratio varies from SoC to Soc. 393 394 CONFIG_SYS_FSL_PCIE_COMPAT 395 396 Defines the string to utilize when trying to match PCIe device 397 tree nodes for the given platform. 398 399 CONFIG_SYS_PPC_E500_DEBUG_TLB 400 401 Enables a temporary TLB entry to be used during boot to work 402 around limitations in e500v1 and e500v2 external debugger 403 support. This reduces the portions of the boot code where 404 breakpoints and single stepping do not work. The value of this 405 symbol should be set to the TLB1 entry to be used for this 406 purpose. 407 408 CONFIG_SYS_FSL_ERRATUM_A004510 409 410 Enables a workaround for erratum A004510. If set, 411 then CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV and 412 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY must be set. 413 414 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV 415 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 (optional) 416 417 Defines one or two SoC revisions (low 8 bits of SVR) 418 for which the A004510 workaround should be applied. 419 420 The rest of SVR is either not relevant to the decision 421 of whether the erratum is present (e.g. p2040 versus 422 p2041) or is implied by the build target, which controls 423 whether CONFIG_SYS_FSL_ERRATUM_A004510 is set. 424 425 See Freescale App Note 4493 for more information about 426 this erratum. 427 428 CONFIG_A003399_NOR_WORKAROUND 429 Enables a workaround for IFC erratum A003399. It is only 430 required during NOR boot. 431 432 CONFIG_A008044_WORKAROUND 433 Enables a workaround for T1040/T1042 erratum A008044. It is only 434 required during NAND boot and valid for Rev 1.0 SoC revision 435 436 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY 437 438 This is the value to write into CCSR offset 0x18600 439 according to the A004510 workaround. 440 441 CONFIG_SYS_FSL_DSP_DDR_ADDR 442 This value denotes start offset of DDR memory which is 443 connected exclusively to the DSP cores. 444 445 CONFIG_SYS_FSL_DSP_M2_RAM_ADDR 446 This value denotes start offset of M2 memory 447 which is directly connected to the DSP core. 448 449 CONFIG_SYS_FSL_DSP_M3_RAM_ADDR 450 This value denotes start offset of M3 memory which is directly 451 connected to the DSP core. 452 453 CONFIG_SYS_FSL_DSP_CCSRBAR_DEFAULT 454 This value denotes start offset of DSP CCSR space. 455 456 CONFIG_SYS_FSL_SINGLE_SOURCE_CLK 457 Single Source Clock is clocking mode present in some of FSL SoC's. 458 In this mode, a single differential clock is used to supply 459 clocks to the sysclock, ddrclock and usbclock. 460 461 CONFIG_SYS_CPC_REINIT_F 462 This CONFIG is defined when the CPC is configured as SRAM at the 463 time of U-Boot entry and is required to be re-initialized. 464 465 CONFIG_DEEP_SLEEP 466 Indicates this SoC supports deep sleep feature. If deep sleep is 467 supported, core will start to execute uboot when wakes up. 468 469- Generic CPU options: 470 CONFIG_SYS_GENERIC_GLOBAL_DATA 471 Defines global data is initialized in generic board board_init_f(). 472 If this macro is defined, global data is created and cleared in 473 generic board board_init_f(). Without this macro, architecture/board 474 should initialize global data before calling board_init_f(). 475 476 CONFIG_SYS_BIG_ENDIAN, CONFIG_SYS_LITTLE_ENDIAN 477 478 Defines the endianess of the CPU. Implementation of those 479 values is arch specific. 480 481 CONFIG_SYS_FSL_DDR 482 Freescale DDR driver in use. This type of DDR controller is 483 found in mpc83xx, mpc85xx, mpc86xx as well as some ARM core 484 SoCs. 485 486 CONFIG_SYS_FSL_DDR_ADDR 487 Freescale DDR memory-mapped register base. 488 489 CONFIG_SYS_FSL_DDR_EMU 490 Specify emulator support for DDR. Some DDR features such as 491 deskew training are not available. 492 493 CONFIG_SYS_FSL_DDRC_GEN1 494 Freescale DDR1 controller. 495 496 CONFIG_SYS_FSL_DDRC_GEN2 497 Freescale DDR2 controller. 498 499 CONFIG_SYS_FSL_DDRC_GEN3 500 Freescale DDR3 controller. 501 502 CONFIG_SYS_FSL_DDRC_GEN4 503 Freescale DDR4 controller. 504 505 CONFIG_SYS_FSL_DDRC_ARM_GEN3 506 Freescale DDR3 controller for ARM-based SoCs. 507 508 CONFIG_SYS_FSL_DDR1 509 Board config to use DDR1. It can be enabled for SoCs with 510 Freescale DDR1 or DDR2 controllers, depending on the board 511 implemetation. 512 513 CONFIG_SYS_FSL_DDR2 514 Board config to use DDR2. It can be eanbeld for SoCs with 515 Freescale DDR2 or DDR3 controllers, depending on the board 516 implementation. 517 518 CONFIG_SYS_FSL_DDR3 519 Board config to use DDR3. It can be enabled for SoCs with 520 Freescale DDR3 or DDR3L controllers. 521 522 CONFIG_SYS_FSL_DDR3L 523 Board config to use DDR3L. It can be enabled for SoCs with 524 DDR3L controllers. 525 526 CONFIG_SYS_FSL_DDR4 527 Board config to use DDR4. It can be enabled for SoCs with 528 DDR4 controllers. 529 530 CONFIG_SYS_FSL_IFC_BE 531 Defines the IFC controller register space as Big Endian 532 533 CONFIG_SYS_FSL_IFC_LE 534 Defines the IFC controller register space as Little Endian 535 536 CONFIG_SYS_FSL_PBL_PBI 537 It enables addition of RCW (Power on reset configuration) in built image. 538 Please refer doc/README.pblimage for more details 539 540 CONFIG_SYS_FSL_PBL_RCW 541 It adds PBI(pre-boot instructions) commands in u-boot build image. 542 PBI commands can be used to configure SoC before it starts the execution. 543 Please refer doc/README.pblimage for more details 544 545 CONFIG_SPL_FSL_PBL 546 It adds a target to create boot binary having SPL binary in PBI format 547 concatenated with u-boot binary. 548 549 CONFIG_SYS_FSL_DDR_BE 550 Defines the DDR controller register space as Big Endian 551 552 CONFIG_SYS_FSL_DDR_LE 553 Defines the DDR controller register space as Little Endian 554 555 CONFIG_SYS_FSL_DDR_SDRAM_BASE_PHY 556 Physical address from the view of DDR controllers. It is the 557 same as CONFIG_SYS_DDR_SDRAM_BASE for all Power SoCs. But 558 it could be different for ARM SoCs. 559 560 CONFIG_SYS_FSL_DDR_INTLV_256B 561 DDR controller interleaving on 256-byte. This is a special 562 interleaving mode, handled by Dickens for Freescale layerscape 563 SoCs with ARM core. 564 565 CONFIG_SYS_FSL_DDR_MAIN_NUM_CTRLS 566 Number of controllers used as main memory. 567 568 CONFIG_SYS_FSL_OTHER_DDR_NUM_CTRLS 569 Number of controllers used for other than main memory. 570 571 CONFIG_SYS_FSL_HAS_DP_DDR 572 Defines the SoC has DP-DDR used for DPAA. 573 574 CONFIG_SYS_FSL_SEC_BE 575 Defines the SEC controller register space as Big Endian 576 577 CONFIG_SYS_FSL_SEC_LE 578 Defines the SEC controller register space as Little Endian 579 580- Intel Monahans options: 581 CONFIG_SYS_MONAHANS_RUN_MODE_OSC_RATIO 582 583 Defines the Monahans run mode to oscillator 584 ratio. Valid values are 8, 16, 24, 31. The core 585 frequency is this value multiplied by 13 MHz. 586 587 CONFIG_SYS_MONAHANS_TURBO_RUN_MODE_RATIO 588 589 Defines the Monahans turbo mode to oscillator 590 ratio. Valid values are 1 (default if undefined) and 591 2. The core frequency as calculated above is multiplied 592 by this value. 593 594- MIPS CPU options: 595 CONFIG_SYS_INIT_SP_OFFSET 596 597 Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack 598 pointer. This is needed for the temporary stack before 599 relocation. 600 601 CONFIG_SYS_MIPS_CACHE_MODE 602 603 Cache operation mode for the MIPS CPU. 604 See also arch/mips/include/asm/mipsregs.h. 605 Possible values are: 606 CONF_CM_CACHABLE_NO_WA 607 CONF_CM_CACHABLE_WA 608 CONF_CM_UNCACHED 609 CONF_CM_CACHABLE_NONCOHERENT 610 CONF_CM_CACHABLE_CE 611 CONF_CM_CACHABLE_COW 612 CONF_CM_CACHABLE_CUW 613 CONF_CM_CACHABLE_ACCELERATED 614 615 CONFIG_SYS_XWAY_EBU_BOOTCFG 616 617 Special option for Lantiq XWAY SoCs for booting from NOR flash. 618 See also arch/mips/cpu/mips32/start.S. 619 620 CONFIG_XWAY_SWAP_BYTES 621 622 Enable compilation of tools/xway-swap-bytes needed for Lantiq 623 XWAY SoCs for booting from NOR flash. The U-Boot image needs to 624 be swapped if a flash programmer is used. 625 626- ARM options: 627 CONFIG_SYS_EXCEPTION_VECTORS_HIGH 628 629 Select high exception vectors of the ARM core, e.g., do not 630 clear the V bit of the c1 register of CP15. 631 632 CONFIG_SYS_THUMB_BUILD 633 634 Use this flag to build U-Boot using the Thumb instruction 635 set for ARM architectures. Thumb instruction set provides 636 better code density. For ARM architectures that support 637 Thumb2 this flag will result in Thumb2 code generated by 638 GCC. 639 640 CONFIG_ARM_ERRATA_716044 641 CONFIG_ARM_ERRATA_742230 642 CONFIG_ARM_ERRATA_743622 643 CONFIG_ARM_ERRATA_751472 644 CONFIG_ARM_ERRATA_761320 645 CONFIG_ARM_ERRATA_773022 646 CONFIG_ARM_ERRATA_774769 647 CONFIG_ARM_ERRATA_794072 648 649 If set, the workarounds for these ARM errata are applied early 650 during U-Boot startup. Note that these options force the 651 workarounds to be applied; no CPU-type/version detection 652 exists, unlike the similar options in the Linux kernel. Do not 653 set these options unless they apply! 654 655 COUNTER_FREQUENCY 656 Generic timer clock source frequency. 657 658 COUNTER_FREQUENCY_REAL 659 Generic timer clock source frequency if the real clock is 660 different from COUNTER_FREQUENCY, and can only be determined 661 at run time. 662 663 NOTE: The following can be machine specific errata. These 664 do have ability to provide rudimentary version and machine 665 specific checks, but expect no product checks. 666 CONFIG_ARM_ERRATA_430973 667 CONFIG_ARM_ERRATA_454179 668 CONFIG_ARM_ERRATA_621766 669 CONFIG_ARM_ERRATA_798870 670 CONFIG_ARM_ERRATA_801819 671 672- Tegra SoC options: 673 CONFIG_TEGRA_SUPPORT_NON_SECURE 674 675 Support executing U-Boot in non-secure (NS) mode. Certain 676 impossible actions will be skipped if the CPU is in NS mode, 677 such as ARM architectural timer initialization. 678 679- Linux Kernel Interface: 680 CONFIG_CLOCKS_IN_MHZ 681 682 U-Boot stores all clock information in Hz 683 internally. For binary compatibility with older Linux 684 kernels (which expect the clocks passed in the 685 bd_info data to be in MHz) the environment variable 686 "clocks_in_mhz" can be defined so that U-Boot 687 converts clock data to MHZ before passing it to the 688 Linux kernel. 689 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of 690 "clocks_in_mhz=1" is automatically included in the 691 default environment. 692 693 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only] 694 695 When transferring memsize parameter to Linux, some versions 696 expect it to be in bytes, others in MB. 697 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes. 698 699 CONFIG_OF_LIBFDT 700 701 New kernel versions are expecting firmware settings to be 702 passed using flattened device trees (based on open firmware 703 concepts). 704 705 CONFIG_OF_LIBFDT 706 * New libfdt-based support 707 * Adds the "fdt" command 708 * The bootm command automatically updates the fdt 709 710 OF_CPU - The proper name of the cpus node (only required for 711 MPC512X and MPC5xxx based boards). 712 OF_SOC - The proper name of the soc node (only required for 713 MPC512X and MPC5xxx based boards). 714 OF_TBCLK - The timebase frequency. 715 OF_STDOUT_PATH - The path to the console device 716 717 boards with QUICC Engines require OF_QE to set UCC MAC 718 addresses 719 720 CONFIG_OF_BOARD_SETUP 721 722 Board code has addition modification that it wants to make 723 to the flat device tree before handing it off to the kernel 724 725 CONFIG_OF_SYSTEM_SETUP 726 727 Other code has addition modification that it wants to make 728 to the flat device tree before handing it off to the kernel. 729 This causes ft_system_setup() to be called before booting 730 the kernel. 731 732 CONFIG_OF_BOOT_CPU 733 734 This define fills in the correct boot CPU in the boot 735 param header, the default value is zero if undefined. 736 737 CONFIG_OF_IDE_FIXUP 738 739 U-Boot can detect if an IDE device is present or not. 740 If not, and this new config option is activated, U-Boot 741 removes the ATA node from the DTS before booting Linux, 742 so the Linux IDE driver does not probe the device and 743 crash. This is needed for buggy hardware (uc101) where 744 no pull down resistor is connected to the signal IDE5V_DD7. 745 746 CONFIG_MACH_TYPE [relevant for ARM only][mandatory] 747 748 This setting is mandatory for all boards that have only one 749 machine type and must be used to specify the machine type 750 number as it appears in the ARM machine registry 751 (see http://www.arm.linux.org.uk/developer/machines/). 752 Only boards that have multiple machine types supported 753 in a single configuration file and the machine type is 754 runtime discoverable, do not have to use this setting. 755 756- vxWorks boot parameters: 757 758 bootvx constructs a valid bootline using the following 759 environments variables: bootdev, bootfile, ipaddr, netmask, 760 serverip, gatewayip, hostname, othbootargs. 761 It loads the vxWorks image pointed bootfile. 762 763 Note: If a "bootargs" environment is defined, it will overwride 764 the defaults discussed just above. 765 766- Cache Configuration: 767 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot 768 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot 769 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot 770 771- Cache Configuration for ARM: 772 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache 773 controller 774 CONFIG_SYS_PL310_BASE - Physical base address of PL310 775 controller register space 776 777- Serial Ports: 778 CONFIG_PL010_SERIAL 779 780 Define this if you want support for Amba PrimeCell PL010 UARTs. 781 782 CONFIG_PL011_SERIAL 783 784 Define this if you want support for Amba PrimeCell PL011 UARTs. 785 786 CONFIG_PL011_CLOCK 787 788 If you have Amba PrimeCell PL011 UARTs, set this variable to 789 the clock speed of the UARTs. 790 791 CONFIG_PL01x_PORTS 792 793 If you have Amba PrimeCell PL010 or PL011 UARTs on your board, 794 define this to a list of base addresses for each (supported) 795 port. See e.g. include/configs/versatile.h 796 797 CONFIG_SERIAL_HW_FLOW_CONTROL 798 799 Define this variable to enable hw flow control in serial driver. 800 Current user of this option is drivers/serial/nsl16550.c driver 801 802- Console Interface: 803 Depending on board, define exactly one serial port 804 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2, 805 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial 806 console by defining CONFIG_8xx_CONS_NONE 807 808 Note: if CONFIG_8xx_CONS_NONE is defined, the serial 809 port routines must be defined elsewhere 810 (i.e. serial_init(), serial_getc(), ...) 811 812 CONFIG_CFB_CONSOLE 813 Enables console device for a color framebuffer. Needs following 814 defines (cf. smiLynxEM, i8042) 815 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation 816 (default big endian) 817 VIDEO_HW_RECTFILL graphic chip supports 818 rectangle fill 819 (cf. smiLynxEM) 820 VIDEO_HW_BITBLT graphic chip supports 821 bit-blit (cf. smiLynxEM) 822 VIDEO_VISIBLE_COLS visible pixel columns 823 (cols=pitch) 824 VIDEO_VISIBLE_ROWS visible pixel rows 825 VIDEO_PIXEL_SIZE bytes per pixel 826 VIDEO_DATA_FORMAT graphic data format 827 (0-5, cf. cfb_console.c) 828 VIDEO_FB_ADRS framebuffer address 829 VIDEO_KBD_INIT_FCT keyboard int fct 830 (i.e. rx51_kp_init()) 831 VIDEO_TSTC_FCT test char fct 832 (i.e. rx51_kp_tstc) 833 VIDEO_GETC_FCT get char fct 834 (i.e. rx51_kp_getc) 835 CONFIG_VIDEO_LOGO display Linux logo in 836 upper left corner 837 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of 838 linux_logo.h for logo. 839 Requires CONFIG_VIDEO_LOGO 840 CONFIG_CONSOLE_EXTRA_INFO 841 additional board info beside 842 the logo 843 844 When CONFIG_CFB_CONSOLE_ANSI is defined, console will support 845 a limited number of ANSI escape sequences (cursor control, 846 erase functions and limited graphics rendition control). 847 848 When CONFIG_CFB_CONSOLE is defined, video console is 849 default i/o. Serial console can be forced with 850 environment 'console=serial'. 851 852 When CONFIG_SILENT_CONSOLE is defined, all console 853 messages (by U-Boot and Linux!) can be silenced with 854 the "silent" environment variable. See 855 doc/README.silent for more information. 856 857 CONFIG_SYS_CONSOLE_BG_COL: define the backgroundcolor, default 858 is 0x00. 859 CONFIG_SYS_CONSOLE_FG_COL: define the foregroundcolor, default 860 is 0xa0. 861 862- Console Baudrate: 863 CONFIG_BAUDRATE - in bps 864 Select one of the baudrates listed in 865 CONFIG_SYS_BAUDRATE_TABLE, see below. 866 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale 867 868- Console Rx buffer length 869 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define 870 the maximum receive buffer length for the SMC. 871 This option is actual only for 82xx and 8xx possible. 872 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE 873 must be defined, to setup the maximum idle timeout for 874 the SMC. 875 876- Pre-Console Buffer: 877 Prior to the console being initialised (i.e. serial UART 878 initialised etc) all console output is silently discarded. 879 Defining CONFIG_PRE_CONSOLE_BUFFER will cause U-Boot to 880 buffer any console messages prior to the console being 881 initialised to a buffer of size CONFIG_PRE_CON_BUF_SZ 882 bytes located at CONFIG_PRE_CON_BUF_ADDR. The buffer is 883 a circular buffer, so if more than CONFIG_PRE_CON_BUF_SZ 884 bytes are output before the console is initialised, the 885 earlier bytes are discarded. 886 887 Note that when printing the buffer a copy is made on the 888 stack so CONFIG_PRE_CON_BUF_SZ must fit on the stack. 889 890 'Sane' compilers will generate smaller code if 891 CONFIG_PRE_CON_BUF_SZ is a power of 2 892 893- Boot Delay: CONFIG_BOOTDELAY - in seconds 894 Delay before automatically booting the default image; 895 set to -1 to disable autoboot. 896 set to -2 to autoboot with no delay and not check for abort 897 (even when CONFIG_ZERO_BOOTDELAY_CHECK is defined). 898 899 See doc/README.autoboot for these options that 900 work with CONFIG_BOOTDELAY. None are required. 901 CONFIG_BOOT_RETRY_TIME 902 CONFIG_BOOT_RETRY_MIN 903 CONFIG_AUTOBOOT_KEYED 904 CONFIG_AUTOBOOT_PROMPT 905 CONFIG_AUTOBOOT_DELAY_STR 906 CONFIG_AUTOBOOT_STOP_STR 907 CONFIG_ZERO_BOOTDELAY_CHECK 908 CONFIG_RESET_TO_RETRY 909 910- Autoboot Command: 911 CONFIG_BOOTCOMMAND 912 Only needed when CONFIG_BOOTDELAY is enabled; 913 define a command string that is automatically executed 914 when no character is read on the console interface 915 within "Boot Delay" after reset. 916 917 CONFIG_BOOTARGS 918 This can be used to pass arguments to the bootm 919 command. The value of CONFIG_BOOTARGS goes into the 920 environment value "bootargs". 921 922 CONFIG_RAMBOOT and CONFIG_NFSBOOT 923 The value of these goes into the environment as 924 "ramboot" and "nfsboot" respectively, and can be used 925 as a convenience, when switching between booting from 926 RAM and NFS. 927 928- Bootcount: 929 CONFIG_BOOTCOUNT_LIMIT 930 Implements a mechanism for detecting a repeating reboot 931 cycle, see: 932 http://www.denx.de/wiki/view/DULG/UBootBootCountLimit 933 934 CONFIG_BOOTCOUNT_ENV 935 If no softreset save registers are found on the hardware 936 "bootcount" is stored in the environment. To prevent a 937 saveenv on all reboots, the environment variable 938 "upgrade_available" is used. If "upgrade_available" is 939 0, "bootcount" is always 0, if "upgrade_available" is 940 1 "bootcount" is incremented in the environment. 941 So the Userspace Applikation must set the "upgrade_available" 942 and "bootcount" variable to 0, if a boot was successfully. 943 944- Pre-Boot Commands: 945 CONFIG_PREBOOT 946 947 When this option is #defined, the existence of the 948 environment variable "preboot" will be checked 949 immediately before starting the CONFIG_BOOTDELAY 950 countdown and/or running the auto-boot command resp. 951 entering interactive mode. 952 953 This feature is especially useful when "preboot" is 954 automatically generated or modified. For an example 955 see the LWMON board specific code: here "preboot" is 956 modified when the user holds down a certain 957 combination of keys on the (special) keyboard when 958 booting the systems 959 960- Serial Download Echo Mode: 961 CONFIG_LOADS_ECHO 962 If defined to 1, all characters received during a 963 serial download (using the "loads" command) are 964 echoed back. This might be needed by some terminal 965 emulations (like "cu"), but may as well just take 966 time on others. This setting #define's the initial 967 value of the "loads_echo" environment variable. 968 969- Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined) 970 CONFIG_KGDB_BAUDRATE 971 Select one of the baudrates listed in 972 CONFIG_SYS_BAUDRATE_TABLE, see below. 973 974- Monitor Functions: 975 Monitor commands can be included or excluded 976 from the build by using the #include files 977 <config_cmd_all.h> and #undef'ing unwanted 978 commands, or adding #define's for wanted commands. 979 980 The default command configuration includes all commands 981 except those marked below with a "*". 982 983 CONFIG_CMD_AES AES 128 CBC encrypt/decrypt 984 CONFIG_CMD_ASKENV * ask for env variable 985 CONFIG_CMD_BDI bdinfo 986 CONFIG_CMD_BEDBUG * Include BedBug Debugger 987 CONFIG_CMD_BMP * BMP support 988 CONFIG_CMD_BSP * Board specific commands 989 CONFIG_CMD_BOOTD bootd 990 CONFIG_CMD_BOOTI * ARM64 Linux kernel Image support 991 CONFIG_CMD_CACHE * icache, dcache 992 CONFIG_CMD_CLK * clock command support 993 CONFIG_CMD_CONSOLE coninfo 994 CONFIG_CMD_CRC32 * crc32 995 CONFIG_CMD_DATE * support for RTC, date/time... 996 CONFIG_CMD_DHCP * DHCP support 997 CONFIG_CMD_DIAG * Diagnostics 998 CONFIG_CMD_DS4510 * ds4510 I2C gpio commands 999 CONFIG_CMD_DS4510_INFO * ds4510 I2C info command 1000 CONFIG_CMD_DS4510_MEM * ds4510 I2C eeprom/sram commansd 1001 CONFIG_CMD_DS4510_RST * ds4510 I2C rst command 1002 CONFIG_CMD_DTT * Digital Therm and Thermostat 1003 CONFIG_CMD_ECHO echo arguments 1004 CONFIG_CMD_EDITENV edit env variable 1005 CONFIG_CMD_EEPROM * EEPROM read/write support 1006 CONFIG_CMD_ELF * bootelf, bootvx 1007 CONFIG_CMD_ENV_CALLBACK * display details about env callbacks 1008 CONFIG_CMD_ENV_FLAGS * display details about env flags 1009 CONFIG_CMD_ENV_EXISTS * check existence of env variable 1010 CONFIG_CMD_EXPORTENV * export the environment 1011 CONFIG_CMD_EXT2 * ext2 command support 1012 CONFIG_CMD_EXT4 * ext4 command support 1013 CONFIG_CMD_FS_GENERIC * filesystem commands (e.g. load, ls) 1014 that work for multiple fs types 1015 CONFIG_CMD_FS_UUID * Look up a filesystem UUID 1016 CONFIG_CMD_SAVEENV saveenv 1017 CONFIG_CMD_FDC * Floppy Disk Support 1018 CONFIG_CMD_FAT * FAT command support 1019 CONFIG_CMD_FLASH flinfo, erase, protect 1020 CONFIG_CMD_FPGA FPGA device initialization support 1021 CONFIG_CMD_FUSE * Device fuse support 1022 CONFIG_CMD_GETTIME * Get time since boot 1023 CONFIG_CMD_GO * the 'go' command (exec code) 1024 CONFIG_CMD_GREPENV * search environment 1025 CONFIG_CMD_HASH * calculate hash / digest 1026 CONFIG_CMD_HWFLOW * RTS/CTS hw flow control 1027 CONFIG_CMD_I2C * I2C serial bus support 1028 CONFIG_CMD_IDE * IDE harddisk support 1029 CONFIG_CMD_IMI iminfo 1030 CONFIG_CMD_IMLS List all images found in NOR flash 1031 CONFIG_CMD_IMLS_NAND * List all images found in NAND flash 1032 CONFIG_CMD_IMMAP * IMMR dump support 1033 CONFIG_CMD_IOTRACE * I/O tracing for debugging 1034 CONFIG_CMD_IMPORTENV * import an environment 1035 CONFIG_CMD_INI * import data from an ini file into the env 1036 CONFIG_CMD_IRQ * irqinfo 1037 CONFIG_CMD_ITEST Integer/string test of 2 values 1038 CONFIG_CMD_JFFS2 * JFFS2 Support 1039 CONFIG_CMD_KGDB * kgdb 1040 CONFIG_CMD_LDRINFO * ldrinfo (display Blackfin loader) 1041 CONFIG_CMD_LINK_LOCAL * link-local IP address auto-configuration 1042 (169.254.*.*) 1043 CONFIG_CMD_LOADB loadb 1044 CONFIG_CMD_LOADS loads 1045 CONFIG_CMD_MD5SUM * print md5 message digest 1046 (requires CONFIG_CMD_MEMORY and CONFIG_MD5) 1047 CONFIG_CMD_MEMINFO * Display detailed memory information 1048 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base, 1049 loop, loopw 1050 CONFIG_CMD_MEMTEST * mtest 1051 CONFIG_CMD_MISC Misc functions like sleep etc 1052 CONFIG_CMD_MMC * MMC memory mapped support 1053 CONFIG_CMD_MII * MII utility commands 1054 CONFIG_CMD_MTDPARTS * MTD partition support 1055 CONFIG_CMD_NAND * NAND support 1056 CONFIG_CMD_NET bootp, tftpboot, rarpboot 1057 CONFIG_CMD_NFS NFS support 1058 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands 1059 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command 1060 CONFIG_CMD_PCI * pciinfo 1061 CONFIG_CMD_PCMCIA * PCMCIA support 1062 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network 1063 host 1064 CONFIG_CMD_PORTIO * Port I/O 1065 CONFIG_CMD_READ * Read raw data from partition 1066 CONFIG_CMD_REGINFO * Register dump 1067 CONFIG_CMD_RUN run command in env variable 1068 CONFIG_CMD_SANDBOX * sb command to access sandbox features 1069 CONFIG_CMD_SAVES * save S record dump 1070 CONFIG_CMD_SCSI * SCSI Support 1071 CONFIG_CMD_SDRAM * print SDRAM configuration information 1072 (requires CONFIG_CMD_I2C) 1073 CONFIG_CMD_SETGETDCR Support for DCR Register access 1074 (4xx only) 1075 CONFIG_CMD_SF * Read/write/erase SPI NOR flash 1076 CONFIG_CMD_SHA1SUM * print sha1 memory digest 1077 (requires CONFIG_CMD_MEMORY) 1078 CONFIG_CMD_SOFTSWITCH * Soft switch setting command for BF60x 1079 CONFIG_CMD_SOURCE "source" command Support 1080 CONFIG_CMD_SPI * SPI serial bus support 1081 CONFIG_CMD_TFTPSRV * TFTP transfer in server mode 1082 CONFIG_CMD_TFTPPUT * TFTP put command (upload) 1083 CONFIG_CMD_TIME * run command and report execution time (ARM specific) 1084 CONFIG_CMD_TIMER * access to the system tick timer 1085 CONFIG_CMD_USB * USB support 1086 CONFIG_CMD_CDP * Cisco Discover Protocol support 1087 CONFIG_CMD_MFSL * Microblaze FSL support 1088 CONFIG_CMD_XIMG Load part of Multi Image 1089 CONFIG_CMD_UUID * Generate random UUID or GUID string 1090 1091 EXAMPLE: If you want all functions except of network 1092 support you can write: 1093 1094 #include "config_cmd_all.h" 1095 #undef CONFIG_CMD_NET 1096 1097 Other Commands: 1098 fdt (flattened device tree) command: CONFIG_OF_LIBFDT 1099 1100 Note: Don't enable the "icache" and "dcache" commands 1101 (configuration option CONFIG_CMD_CACHE) unless you know 1102 what you (and your U-Boot users) are doing. Data 1103 cache cannot be enabled on systems like the 8xx or 1104 8260 (where accesses to the IMMR region must be 1105 uncached), and it cannot be disabled on all other 1106 systems where we (mis-) use the data cache to hold an 1107 initial stack and some data. 1108 1109 1110 XXX - this list needs to get updated! 1111 1112- Regular expression support: 1113 CONFIG_REGEX 1114 If this variable is defined, U-Boot is linked against 1115 the SLRE (Super Light Regular Expression) library, 1116 which adds regex support to some commands, as for 1117 example "env grep" and "setexpr". 1118 1119- Device tree: 1120 CONFIG_OF_CONTROL 1121 If this variable is defined, U-Boot will use a device tree 1122 to configure its devices, instead of relying on statically 1123 compiled #defines in the board file. This option is 1124 experimental and only available on a few boards. The device 1125 tree is available in the global data as gd->fdt_blob. 1126 1127 U-Boot needs to get its device tree from somewhere. This can 1128 be done using one of the two options below: 1129 1130 CONFIG_OF_EMBED 1131 If this variable is defined, U-Boot will embed a device tree 1132 binary in its image. This device tree file should be in the 1133 board directory and called <soc>-<board>.dts. The binary file 1134 is then picked up in board_init_f() and made available through 1135 the global data structure as gd->blob. 1136 1137 CONFIG_OF_SEPARATE 1138 If this variable is defined, U-Boot will build a device tree 1139 binary. It will be called u-boot.dtb. Architecture-specific 1140 code will locate it at run-time. Generally this works by: 1141 1142 cat u-boot.bin u-boot.dtb >image.bin 1143 1144 and in fact, U-Boot does this for you, creating a file called 1145 u-boot-dtb.bin which is useful in the common case. You can 1146 still use the individual files if you need something more 1147 exotic. 1148 1149- Watchdog: 1150 CONFIG_WATCHDOG 1151 If this variable is defined, it enables watchdog 1152 support for the SoC. There must be support in the SoC 1153 specific code for a watchdog. For the 8xx and 8260 1154 CPUs, the SIU Watchdog feature is enabled in the SYPCR 1155 register. When supported for a specific SoC is 1156 available, then no further board specific code should 1157 be needed to use it. 1158 1159 CONFIG_HW_WATCHDOG 1160 When using a watchdog circuitry external to the used 1161 SoC, then define this variable and provide board 1162 specific code for the "hw_watchdog_reset" function. 1163 1164 CONFIG_AT91_HW_WDT_TIMEOUT 1165 specify the timeout in seconds. default 2 seconds. 1166 1167- U-Boot Version: 1168 CONFIG_VERSION_VARIABLE 1169 If this variable is defined, an environment variable 1170 named "ver" is created by U-Boot showing the U-Boot 1171 version as printed by the "version" command. 1172 Any change to this variable will be reverted at the 1173 next reset. 1174 1175- Real-Time Clock: 1176 1177 When CONFIG_CMD_DATE is selected, the type of the RTC 1178 has to be selected, too. Define exactly one of the 1179 following options: 1180 1181 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx 1182 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC 1183 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC 1184 CONFIG_RTC_MC146818 - use MC146818 RTC 1185 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC 1186 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC 1187 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC 1188 CONFIG_RTC_DS1339 - use Maxim, Inc. DS1339 RTC 1189 CONFIG_RTC_DS164x - use Dallas DS164x RTC 1190 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC 1191 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC 1192 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337 1193 CONFIG_SYS_RV3029_TCR - enable trickle charger on 1194 RV3029 RTC. 1195 1196 Note that if the RTC uses I2C, then the I2C interface 1197 must also be configured. See I2C Support, below. 1198 1199- GPIO Support: 1200 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO 1201 1202 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of 1203 chip-ngpio pairs that tell the PCA953X driver the number of 1204 pins supported by a particular chip. 1205 1206 Note that if the GPIO device uses I2C, then the I2C interface 1207 must also be configured. See I2C Support, below. 1208 1209- I/O tracing: 1210 When CONFIG_IO_TRACE is selected, U-Boot intercepts all I/O 1211 accesses and can checksum them or write a list of them out 1212 to memory. See the 'iotrace' command for details. This is 1213 useful for testing device drivers since it can confirm that 1214 the driver behaves the same way before and after a code 1215 change. Currently this is supported on sandbox and arm. To 1216 add support for your architecture, add '#include <iotrace.h>' 1217 to the bottom of arch/<arch>/include/asm/io.h and test. 1218 1219 Example output from the 'iotrace stats' command is below. 1220 Note that if the trace buffer is exhausted, the checksum will 1221 still continue to operate. 1222 1223 iotrace is enabled 1224 Start: 10000000 (buffer start address) 1225 Size: 00010000 (buffer size) 1226 Offset: 00000120 (current buffer offset) 1227 Output: 10000120 (start + offset) 1228 Count: 00000018 (number of trace records) 1229 CRC32: 9526fb66 (CRC32 of all trace records) 1230 1231- Timestamp Support: 1232 1233 When CONFIG_TIMESTAMP is selected, the timestamp 1234 (date and time) of an image is printed by image 1235 commands like bootm or iminfo. This option is 1236 automatically enabled when you select CONFIG_CMD_DATE . 1237 1238- Partition Labels (disklabels) Supported: 1239 Zero or more of the following: 1240 CONFIG_MAC_PARTITION Apple's MacOS partition table. 1241 CONFIG_DOS_PARTITION MS Dos partition table, traditional on the 1242 Intel architecture, USB sticks, etc. 1243 CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc. 1244 CONFIG_EFI_PARTITION GPT partition table, common when EFI is the 1245 bootloader. Note 2TB partition limit; see 1246 disk/part_efi.c 1247 CONFIG_MTD_PARTITIONS Memory Technology Device partition table. 1248 1249 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or 1250 CONFIG_CMD_SCSI) you must configure support for at 1251 least one non-MTD partition type as well. 1252 1253- IDE Reset method: 1254 CONFIG_IDE_RESET_ROUTINE - this is defined in several 1255 board configurations files but used nowhere! 1256 1257 CONFIG_IDE_RESET - is this is defined, IDE Reset will 1258 be performed by calling the function 1259 ide_set_reset(int reset) 1260 which has to be defined in a board specific file 1261 1262- ATAPI Support: 1263 CONFIG_ATAPI 1264 1265 Set this to enable ATAPI support. 1266 1267- LBA48 Support 1268 CONFIG_LBA48 1269 1270 Set this to enable support for disks larger than 137GB 1271 Also look at CONFIG_SYS_64BIT_LBA. 1272 Whithout these , LBA48 support uses 32bit variables and will 'only' 1273 support disks up to 2.1TB. 1274 1275 CONFIG_SYS_64BIT_LBA: 1276 When enabled, makes the IDE subsystem use 64bit sector addresses. 1277 Default is 32bit. 1278 1279- SCSI Support: 1280 At the moment only there is only support for the 1281 SYM53C8XX SCSI controller; define 1282 CONFIG_SCSI_SYM53C8XX to enable it. 1283 1284 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and 1285 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID * 1286 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the 1287 maximum numbers of LUNs, SCSI ID's and target 1288 devices. 1289 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz) 1290 1291 The environment variable 'scsidevs' is set to the number of 1292 SCSI devices found during the last scan. 1293 1294- NETWORK Support (PCI): 1295 CONFIG_E1000 1296 Support for Intel 8254x/8257x gigabit chips. 1297 1298 CONFIG_E1000_SPI 1299 Utility code for direct access to the SPI bus on Intel 8257x. 1300 This does not do anything useful unless you set at least one 1301 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC. 1302 1303 CONFIG_E1000_SPI_GENERIC 1304 Allow generic access to the SPI bus on the Intel 8257x, for 1305 example with the "sspi" command. 1306 1307 CONFIG_CMD_E1000 1308 Management command for E1000 devices. When used on devices 1309 with SPI support you can reprogram the EEPROM from U-Boot. 1310 1311 CONFIG_EEPRO100 1312 Support for Intel 82557/82559/82559ER chips. 1313 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM 1314 write routine for first time initialisation. 1315 1316 CONFIG_TULIP 1317 Support for Digital 2114x chips. 1318 Optional CONFIG_TULIP_SELECT_MEDIA for board specific 1319 modem chip initialisation (KS8761/QS6611). 1320 1321 CONFIG_NATSEMI 1322 Support for National dp83815 chips. 1323 1324 CONFIG_NS8382X 1325 Support for National dp8382[01] gigabit chips. 1326 1327- NETWORK Support (other): 1328 1329 CONFIG_DRIVER_AT91EMAC 1330 Support for AT91RM9200 EMAC. 1331 1332 CONFIG_RMII 1333 Define this to use reduced MII inteface 1334 1335 CONFIG_DRIVER_AT91EMAC_QUIET 1336 If this defined, the driver is quiet. 1337 The driver doen't show link status messages. 1338 1339 CONFIG_CALXEDA_XGMAC 1340 Support for the Calxeda XGMAC device 1341 1342 CONFIG_LAN91C96 1343 Support for SMSC's LAN91C96 chips. 1344 1345 CONFIG_LAN91C96_BASE 1346 Define this to hold the physical address 1347 of the LAN91C96's I/O space 1348 1349 CONFIG_LAN91C96_USE_32_BIT 1350 Define this to enable 32 bit addressing 1351 1352 CONFIG_SMC91111 1353 Support for SMSC's LAN91C111 chip 1354 1355 CONFIG_SMC91111_BASE 1356 Define this to hold the physical address 1357 of the device (I/O space) 1358 1359 CONFIG_SMC_USE_32_BIT 1360 Define this if data bus is 32 bits 1361 1362 CONFIG_SMC_USE_IOFUNCS 1363 Define this to use i/o functions instead of macros 1364 (some hardware wont work with macros) 1365 1366 CONFIG_DRIVER_TI_EMAC 1367 Support for davinci emac 1368 1369 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT 1370 Define this if you have more then 3 PHYs. 1371 1372 CONFIG_FTGMAC100 1373 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet 1374 1375 CONFIG_FTGMAC100_EGIGA 1376 Define this to use GE link update with gigabit PHY. 1377 Define this if FTGMAC100 is connected to gigabit PHY. 1378 If your system has 10/100 PHY only, it might not occur 1379 wrong behavior. Because PHY usually return timeout or 1380 useless data when polling gigabit status and gigabit 1381 control registers. This behavior won't affect the 1382 correctnessof 10/100 link speed update. 1383 1384 CONFIG_SMC911X 1385 Support for SMSC's LAN911x and LAN921x chips 1386 1387 CONFIG_SMC911X_BASE 1388 Define this to hold the physical address 1389 of the device (I/O space) 1390 1391 CONFIG_SMC911X_32_BIT 1392 Define this if data bus is 32 bits 1393 1394 CONFIG_SMC911X_16_BIT 1395 Define this if data bus is 16 bits. If your processor 1396 automatically converts one 32 bit word to two 16 bit 1397 words you may also try CONFIG_SMC911X_32_BIT. 1398 1399 CONFIG_SH_ETHER 1400 Support for Renesas on-chip Ethernet controller 1401 1402 CONFIG_SH_ETHER_USE_PORT 1403 Define the number of ports to be used 1404 1405 CONFIG_SH_ETHER_PHY_ADDR 1406 Define the ETH PHY's address 1407 1408 CONFIG_SH_ETHER_CACHE_WRITEBACK 1409 If this option is set, the driver enables cache flush. 1410 1411- PWM Support: 1412 CONFIG_PWM_IMX 1413 Support for PWM modul on the imx6. 1414 1415- TPM Support: 1416 CONFIG_TPM 1417 Support TPM devices. 1418 1419 CONFIG_TPM_TIS_INFINEON 1420 Support for Infineon i2c bus TPM devices. Only one device 1421 per system is supported at this time. 1422 1423 CONFIG_TPM_TIS_I2C_BURST_LIMITATION 1424 Define the burst count bytes upper limit 1425 1426 CONFIG_TPM_ST33ZP24 1427 Support for STMicroelectronics TPM devices. Requires DM_TPM support. 1428 1429 CONFIG_TPM_ST33ZP24_I2C 1430 Support for STMicroelectronics ST33ZP24 I2C devices. 1431 Requires TPM_ST33ZP24 and I2C. 1432 1433 CONFIG_TPM_ST33ZP24_SPI 1434 Support for STMicroelectronics ST33ZP24 SPI devices. 1435 Requires TPM_ST33ZP24 and SPI. 1436 1437 CONFIG_TPM_ATMEL_TWI 1438 Support for Atmel TWI TPM device. Requires I2C support. 1439 1440 CONFIG_TPM_TIS_LPC 1441 Support for generic parallel port TPM devices. Only one device 1442 per system is supported at this time. 1443 1444 CONFIG_TPM_TIS_BASE_ADDRESS 1445 Base address where the generic TPM device is mapped 1446 to. Contemporary x86 systems usually map it at 1447 0xfed40000. 1448 1449 CONFIG_CMD_TPM 1450 Add tpm monitor functions. 1451 Requires CONFIG_TPM. If CONFIG_TPM_AUTH_SESSIONS is set, also 1452 provides monitor access to authorized functions. 1453 1454 CONFIG_TPM 1455 Define this to enable the TPM support library which provides 1456 functional interfaces to some TPM commands. 1457 Requires support for a TPM device. 1458 1459 CONFIG_TPM_AUTH_SESSIONS 1460 Define this to enable authorized functions in the TPM library. 1461 Requires CONFIG_TPM and CONFIG_SHA1. 1462 1463- USB Support: 1464 At the moment only the UHCI host controller is 1465 supported (PIP405, MIP405, MPC5200); define 1466 CONFIG_USB_UHCI to enable it. 1467 define CONFIG_USB_KEYBOARD to enable the USB Keyboard 1468 and define CONFIG_USB_STORAGE to enable the USB 1469 storage devices. 1470 Note: 1471 Supported are USB Keyboards and USB Floppy drives 1472 (TEAC FD-05PUB). 1473 MPC5200 USB requires additional defines: 1474 CONFIG_USB_CLOCK 1475 for 528 MHz Clock: 0x0001bbbb 1476 CONFIG_PSC3_USB 1477 for USB on PSC3 1478 CONFIG_USB_CONFIG 1479 for differential drivers: 0x00001000 1480 for single ended drivers: 0x00005000 1481 for differential drivers on PSC3: 0x00000100 1482 for single ended drivers on PSC3: 0x00004100 1483 CONFIG_SYS_USB_EVENT_POLL 1484 May be defined to allow interrupt polling 1485 instead of using asynchronous interrupts 1486 1487 CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the 1488 txfilltuning field in the EHCI controller on reset. 1489 1490 CONFIG_USB_DWC2_REG_ADDR the physical CPU address of the DWC2 1491 HW module registers. 1492 1493- USB Device: 1494 Define the below if you wish to use the USB console. 1495 Once firmware is rebuilt from a serial console issue the 1496 command "setenv stdin usbtty; setenv stdout usbtty" and 1497 attach your USB cable. The Unix command "dmesg" should print 1498 it has found a new device. The environment variable usbtty 1499 can be set to gserial or cdc_acm to enable your device to 1500 appear to a USB host as a Linux gserial device or a 1501 Common Device Class Abstract Control Model serial device. 1502 If you select usbtty = gserial you should be able to enumerate 1503 a Linux host by 1504 # modprobe usbserial vendor=0xVendorID product=0xProductID 1505 else if using cdc_acm, simply setting the environment 1506 variable usbtty to be cdc_acm should suffice. The following 1507 might be defined in YourBoardName.h 1508 1509 CONFIG_USB_DEVICE 1510 Define this to build a UDC device 1511 1512 CONFIG_USB_TTY 1513 Define this to have a tty type of device available to 1514 talk to the UDC device 1515 1516 CONFIG_USBD_HS 1517 Define this to enable the high speed support for usb 1518 device and usbtty. If this feature is enabled, a routine 1519 int is_usbd_high_speed(void) 1520 also needs to be defined by the driver to dynamically poll 1521 whether the enumeration has succeded at high speed or full 1522 speed. 1523 1524 CONFIG_SYS_CONSOLE_IS_IN_ENV 1525 Define this if you want stdin, stdout &/or stderr to 1526 be set to usbtty. 1527 1528 mpc8xx: 1529 CONFIG_SYS_USB_EXTC_CLK 0xBLAH 1530 Derive USB clock from external clock "blah" 1531 - CONFIG_SYS_USB_EXTC_CLK 0x02 1532 1533 CONFIG_SYS_USB_BRG_CLK 0xBLAH 1534 Derive USB clock from brgclk 1535 - CONFIG_SYS_USB_BRG_CLK 0x04 1536 1537 If you have a USB-IF assigned VendorID then you may wish to 1538 define your own vendor specific values either in BoardName.h 1539 or directly in usbd_vendor_info.h. If you don't define 1540 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME, 1541 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot 1542 should pretend to be a Linux device to it's target host. 1543 1544 CONFIG_USBD_MANUFACTURER 1545 Define this string as the name of your company for 1546 - CONFIG_USBD_MANUFACTURER "my company" 1547 1548 CONFIG_USBD_PRODUCT_NAME 1549 Define this string as the name of your product 1550 - CONFIG_USBD_PRODUCT_NAME "acme usb device" 1551 1552 CONFIG_USBD_VENDORID 1553 Define this as your assigned Vendor ID from the USB 1554 Implementors Forum. This *must* be a genuine Vendor ID 1555 to avoid polluting the USB namespace. 1556 - CONFIG_USBD_VENDORID 0xFFFF 1557 1558 CONFIG_USBD_PRODUCTID 1559 Define this as the unique Product ID 1560 for your device 1561 - CONFIG_USBD_PRODUCTID 0xFFFF 1562 1563- ULPI Layer Support: 1564 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via 1565 the generic ULPI layer. The generic layer accesses the ULPI PHY 1566 via the platform viewport, so you need both the genric layer and 1567 the viewport enabled. Currently only Chipidea/ARC based 1568 viewport is supported. 1569 To enable the ULPI layer support, define CONFIG_USB_ULPI and 1570 CONFIG_USB_ULPI_VIEWPORT in your board configuration file. 1571 If your ULPI phy needs a different reference clock than the 1572 standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to 1573 the appropriate value in Hz. 1574 1575- MMC Support: 1576 The MMC controller on the Intel PXA is supported. To 1577 enable this define CONFIG_MMC. The MMC can be 1578 accessed from the boot prompt by mapping the device 1579 to physical memory similar to flash. Command line is 1580 enabled with CONFIG_CMD_MMC. The MMC driver also works with 1581 the FAT fs. This is enabled with CONFIG_CMD_FAT. 1582 1583 CONFIG_SH_MMCIF 1584 Support for Renesas on-chip MMCIF controller 1585 1586 CONFIG_SH_MMCIF_ADDR 1587 Define the base address of MMCIF registers 1588 1589 CONFIG_SH_MMCIF_CLK 1590 Define the clock frequency for MMCIF 1591 1592 CONFIG_GENERIC_MMC 1593 Enable the generic MMC driver 1594 1595 CONFIG_SUPPORT_EMMC_BOOT 1596 Enable some additional features of the eMMC boot partitions. 1597 1598 CONFIG_SUPPORT_EMMC_RPMB 1599 Enable the commands for reading, writing and programming the 1600 key for the Replay Protection Memory Block partition in eMMC. 1601 1602- USB Device Firmware Update (DFU) class support: 1603 CONFIG_USB_FUNCTION_DFU 1604 This enables the USB portion of the DFU USB class 1605 1606 CONFIG_CMD_DFU 1607 This enables the command "dfu" which is used to have 1608 U-Boot create a DFU class device via USB. This command 1609 requires that the "dfu_alt_info" environment variable be 1610 set and define the alt settings to expose to the host. 1611 1612 CONFIG_DFU_MMC 1613 This enables support for exposing (e)MMC devices via DFU. 1614 1615 CONFIG_DFU_NAND 1616 This enables support for exposing NAND devices via DFU. 1617 1618 CONFIG_DFU_RAM 1619 This enables support for exposing RAM via DFU. 1620 Note: DFU spec refer to non-volatile memory usage, but 1621 allow usages beyond the scope of spec - here RAM usage, 1622 one that would help mostly the developer. 1623 1624 CONFIG_SYS_DFU_DATA_BUF_SIZE 1625 Dfu transfer uses a buffer before writing data to the 1626 raw storage device. Make the size (in bytes) of this buffer 1627 configurable. The size of this buffer is also configurable 1628 through the "dfu_bufsiz" environment variable. 1629 1630 CONFIG_SYS_DFU_MAX_FILE_SIZE 1631 When updating files rather than the raw storage device, 1632 we use a static buffer to copy the file into and then write 1633 the buffer once we've been given the whole file. Define 1634 this to the maximum filesize (in bytes) for the buffer. 1635 Default is 4 MiB if undefined. 1636 1637 DFU_DEFAULT_POLL_TIMEOUT 1638 Poll timeout [ms], is the timeout a device can send to the 1639 host. The host must wait for this timeout before sending 1640 a subsequent DFU_GET_STATUS request to the device. 1641 1642 DFU_MANIFEST_POLL_TIMEOUT 1643 Poll timeout [ms], which the device sends to the host when 1644 entering dfuMANIFEST state. Host waits this timeout, before 1645 sending again an USB request to the device. 1646 1647- USB Device Android Fastboot support: 1648 CONFIG_USB_FUNCTION_FASTBOOT 1649 This enables the USB part of the fastboot gadget 1650 1651 CONFIG_CMD_FASTBOOT 1652 This enables the command "fastboot" which enables the Android 1653 fastboot mode for the platform's USB device. Fastboot is a USB 1654 protocol for downloading images, flashing and device control 1655 used on Android devices. 1656 See doc/README.android-fastboot for more information. 1657 1658 CONFIG_ANDROID_BOOT_IMAGE 1659 This enables support for booting images which use the Android 1660 image format header. 1661 1662 CONFIG_FASTBOOT_BUF_ADDR 1663 The fastboot protocol requires a large memory buffer for 1664 downloads. Define this to the starting RAM address to use for 1665 downloaded images. 1666 1667 CONFIG_FASTBOOT_BUF_SIZE 1668 The fastboot protocol requires a large memory buffer for 1669 downloads. This buffer should be as large as possible for a 1670 platform. Define this to the size available RAM for fastboot. 1671 1672 CONFIG_FASTBOOT_FLASH 1673 The fastboot protocol includes a "flash" command for writing 1674 the downloaded image to a non-volatile storage device. Define 1675 this to enable the "fastboot flash" command. 1676 1677 CONFIG_FASTBOOT_FLASH_MMC_DEV 1678 The fastboot "flash" command requires additional information 1679 regarding the non-volatile storage device. Define this to 1680 the eMMC device that fastboot should use to store the image. 1681 1682 CONFIG_FASTBOOT_GPT_NAME 1683 The fastboot "flash" command supports writing the downloaded 1684 image to the Protective MBR and the Primary GUID Partition 1685 Table. (Additionally, this downloaded image is post-processed 1686 to generate and write the Backup GUID Partition Table.) 1687 This occurs when the specified "partition name" on the 1688 "fastboot flash" command line matches this value. 1689 Default is GPT_ENTRY_NAME (currently "gpt") if undefined. 1690 1691- Journaling Flash filesystem support: 1692 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE, 1693 CONFIG_JFFS2_NAND_DEV 1694 Define these for a default partition on a NAND device 1695 1696 CONFIG_SYS_JFFS2_FIRST_SECTOR, 1697 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS 1698 Define these for a default partition on a NOR device 1699 1700 CONFIG_SYS_JFFS_CUSTOM_PART 1701 Define this to create an own partition. You have to provide a 1702 function struct part_info* jffs2_part_info(int part_num) 1703 1704 If you define only one JFFS2 partition you may also want to 1705 #define CONFIG_SYS_JFFS_SINGLE_PART 1 1706 to disable the command chpart. This is the default when you 1707 have not defined a custom partition 1708 1709- FAT(File Allocation Table) filesystem write function support: 1710 CONFIG_FAT_WRITE 1711 1712 Define this to enable support for saving memory data as a 1713 file in FAT formatted partition. 1714 1715 This will also enable the command "fatwrite" enabling the 1716 user to write files to FAT. 1717 1718CBFS (Coreboot Filesystem) support 1719 CONFIG_CMD_CBFS 1720 1721 Define this to enable support for reading from a Coreboot 1722 filesystem. Available commands are cbfsinit, cbfsinfo, cbfsls 1723 and cbfsload. 1724 1725- FAT(File Allocation Table) filesystem cluster size: 1726 CONFIG_FS_FAT_MAX_CLUSTSIZE 1727 1728 Define the max cluster size for fat operations else 1729 a default value of 65536 will be defined. 1730 1731- Keyboard Support: 1732 See Kconfig help for available keyboard drivers. 1733 1734 CONFIG_KEYBOARD 1735 1736 Define this to enable a custom keyboard support. 1737 This simply calls drv_keyboard_init() which must be 1738 defined in your board-specific files. This option is deprecated 1739 and is only used by novena. For new boards, use driver model 1740 instead. 1741 1742- Video support: 1743 CONFIG_VIDEO 1744 1745 Define this to enable video support (for output to 1746 video). 1747 1748 CONFIG_VIDEO_CT69000 1749 1750 Enable Chips & Technologies 69000 Video chip 1751 1752 CONFIG_VIDEO_SMI_LYNXEM 1753 Enable Silicon Motion SMI 712/710/810 Video chip. The 1754 video output is selected via environment 'videoout' 1755 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is 1756 assumed. 1757 1758 For the CT69000 and SMI_LYNXEM drivers, videomode is 1759 selected via environment 'videomode'. Two different ways 1760 are possible: 1761 - "videomode=num" 'num' is a standard LiLo mode numbers. 1762 Following standard modes are supported (* is default): 1763 1764 Colors 640x480 800x600 1024x768 1152x864 1280x1024 1765 -------------+--------------------------------------------- 1766 8 bits | 0x301* 0x303 0x305 0x161 0x307 1767 15 bits | 0x310 0x313 0x316 0x162 0x319 1768 16 bits | 0x311 0x314 0x317 0x163 0x31A 1769 24 bits | 0x312 0x315 0x318 ? 0x31B 1770 -------------+--------------------------------------------- 1771 (i.e. setenv videomode 317; saveenv; reset;) 1772 1773 - "videomode=bootargs" all the video parameters are parsed 1774 from the bootargs. (See drivers/video/videomodes.c) 1775 1776 1777 CONFIG_VIDEO_SED13806 1778 Enable Epson SED13806 driver. This driver supports 8bpp 1779 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP 1780 or CONFIG_VIDEO_SED13806_16BPP 1781 1782 CONFIG_FSL_DIU_FB 1783 Enable the Freescale DIU video driver. Reference boards for 1784 SOCs that have a DIU should define this macro to enable DIU 1785 support, and should also define these other macros: 1786 1787 CONFIG_SYS_DIU_ADDR 1788 CONFIG_VIDEO 1789 CONFIG_CMD_BMP 1790 CONFIG_CFB_CONSOLE 1791 CONFIG_VIDEO_SW_CURSOR 1792 CONFIG_VGA_AS_SINGLE_DEVICE 1793 CONFIG_VIDEO_LOGO 1794 CONFIG_VIDEO_BMP_LOGO 1795 1796 The DIU driver will look for the 'video-mode' environment 1797 variable, and if defined, enable the DIU as a console during 1798 boot. See the documentation file README.video for a 1799 description of this variable. 1800 1801- LCD Support: CONFIG_LCD 1802 1803 Define this to enable LCD support (for output to LCD 1804 display); also select one of the supported displays 1805 by defining one of these: 1806 1807 CONFIG_ATMEL_LCD: 1808 1809 HITACHI TX09D70VM1CCA, 3.5", 240x320. 1810 1811 CONFIG_NEC_NL6448AC33: 1812 1813 NEC NL6448AC33-18. Active, color, single scan. 1814 1815 CONFIG_NEC_NL6448BC20 1816 1817 NEC NL6448BC20-08. 6.5", 640x480. 1818 Active, color, single scan. 1819 1820 CONFIG_NEC_NL6448BC33_54 1821 1822 NEC NL6448BC33-54. 10.4", 640x480. 1823 Active, color, single scan. 1824 1825 CONFIG_SHARP_16x9 1826 1827 Sharp 320x240. Active, color, single scan. 1828 It isn't 16x9, and I am not sure what it is. 1829 1830 CONFIG_SHARP_LQ64D341 1831 1832 Sharp LQ64D341 display, 640x480. 1833 Active, color, single scan. 1834 1835 CONFIG_HLD1045 1836 1837 HLD1045 display, 640x480. 1838 Active, color, single scan. 1839 1840 CONFIG_OPTREX_BW 1841 1842 Optrex CBL50840-2 NF-FW 99 22 M5 1843 or 1844 Hitachi LMG6912RPFC-00T 1845 or 1846 Hitachi SP14Q002 1847 1848 320x240. Black & white. 1849 1850 Normally display is black on white background; define 1851 CONFIG_SYS_WHITE_ON_BLACK to get it inverted. 1852 1853 CONFIG_LCD_ALIGNMENT 1854 1855 Normally the LCD is page-aligned (typically 4KB). If this is 1856 defined then the LCD will be aligned to this value instead. 1857 For ARM it is sometimes useful to use MMU_SECTION_SIZE 1858 here, since it is cheaper to change data cache settings on 1859 a per-section basis. 1860 1861 CONFIG_CONSOLE_SCROLL_LINES 1862 1863 When the console need to be scrolled, this is the number of 1864 lines to scroll by. It defaults to 1. Increasing this makes 1865 the console jump but can help speed up operation when scrolling 1866 is slow. 1867 1868 CONFIG_LCD_ROTATION 1869 1870 Sometimes, for example if the display is mounted in portrait 1871 mode or even if it's mounted landscape but rotated by 180degree, 1872 we need to rotate our content of the display relative to the 1873 framebuffer, so that user can read the messages which are 1874 printed out. 1875 Once CONFIG_LCD_ROTATION is defined, the lcd_console will be 1876 initialized with a given rotation from "vl_rot" out of 1877 "vidinfo_t" which is provided by the board specific code. 1878 The value for vl_rot is coded as following (matching to 1879 fbcon=rotate:<n> linux-kernel commandline): 1880 0 = no rotation respectively 0 degree 1881 1 = 90 degree rotation 1882 2 = 180 degree rotation 1883 3 = 270 degree rotation 1884 1885 If CONFIG_LCD_ROTATION is not defined, the console will be 1886 initialized with 0degree rotation. 1887 1888 CONFIG_LCD_BMP_RLE8 1889 1890 Support drawing of RLE8-compressed bitmaps on the LCD. 1891 1892 CONFIG_I2C_EDID 1893 1894 Enables an 'i2c edid' command which can read EDID 1895 information over I2C from an attached LCD display. 1896 1897- Splash Screen Support: CONFIG_SPLASH_SCREEN 1898 1899 If this option is set, the environment is checked for 1900 a variable "splashimage". If found, the usual display 1901 of logo, copyright and system information on the LCD 1902 is suppressed and the BMP image at the address 1903 specified in "splashimage" is loaded instead. The 1904 console is redirected to the "nulldev", too. This 1905 allows for a "silent" boot where a splash screen is 1906 loaded very quickly after power-on. 1907 1908 CONFIG_SPLASHIMAGE_GUARD 1909 1910 If this option is set, then U-Boot will prevent the environment 1911 variable "splashimage" from being set to a problematic address 1912 (see README.displaying-bmps). 1913 This option is useful for targets where, due to alignment 1914 restrictions, an improperly aligned BMP image will cause a data 1915 abort. If you think you will not have problems with unaligned 1916 accesses (for example because your toolchain prevents them) 1917 there is no need to set this option. 1918 1919 CONFIG_SPLASH_SCREEN_ALIGN 1920 1921 If this option is set the splash image can be freely positioned 1922 on the screen. Environment variable "splashpos" specifies the 1923 position as "x,y". If a positive number is given it is used as 1924 number of pixel from left/top. If a negative number is given it 1925 is used as number of pixel from right/bottom. You can also 1926 specify 'm' for centering the image. 1927 1928 Example: 1929 setenv splashpos m,m 1930 => image at center of screen 1931 1932 setenv splashpos 30,20 1933 => image at x = 30 and y = 20 1934 1935 setenv splashpos -10,m 1936 => vertically centered image 1937 at x = dspWidth - bmpWidth - 9 1938 1939- Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP 1940 1941 If this option is set, additionally to standard BMP 1942 images, gzipped BMP images can be displayed via the 1943 splashscreen support or the bmp command. 1944 1945- Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8 1946 1947 If this option is set, 8-bit RLE compressed BMP images 1948 can be displayed via the splashscreen support or the 1949 bmp command. 1950 1951- Do compressing for memory range: 1952 CONFIG_CMD_ZIP 1953 1954 If this option is set, it would use zlib deflate method 1955 to compress the specified memory at its best effort. 1956 1957- Compression support: 1958 CONFIG_GZIP 1959 1960 Enabled by default to support gzip compressed images. 1961 1962 CONFIG_BZIP2 1963 1964 If this option is set, support for bzip2 compressed 1965 images is included. If not, only uncompressed and gzip 1966 compressed images are supported. 1967 1968 NOTE: the bzip2 algorithm requires a lot of RAM, so 1969 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should 1970 be at least 4MB. 1971 1972 CONFIG_LZMA 1973 1974 If this option is set, support for lzma compressed 1975 images is included. 1976 1977 Note: The LZMA algorithm adds between 2 and 4KB of code and it 1978 requires an amount of dynamic memory that is given by the 1979 formula: 1980 1981 (1846 + 768 << (lc + lp)) * sizeof(uint16) 1982 1983 Where lc and lp stand for, respectively, Literal context bits 1984 and Literal pos bits. 1985 1986 This value is upper-bounded by 14MB in the worst case. Anyway, 1987 for a ~4MB large kernel image, we have lc=3 and lp=0 for a 1988 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is 1989 a very small buffer. 1990 1991 Use the lzmainfo tool to determinate the lc and lp values and 1992 then calculate the amount of needed dynamic memory (ensuring 1993 the appropriate CONFIG_SYS_MALLOC_LEN value). 1994 1995 CONFIG_LZO 1996 1997 If this option is set, support for LZO compressed images 1998 is included. 1999 2000- MII/PHY support: 2001 CONFIG_PHY_ADDR 2002 2003 The address of PHY on MII bus. 2004 2005 CONFIG_PHY_CLOCK_FREQ (ppc4xx) 2006 2007 The clock frequency of the MII bus 2008 2009 CONFIG_PHY_GIGE 2010 2011 If this option is set, support for speed/duplex 2012 detection of gigabit PHY is included. 2013 2014 CONFIG_PHY_RESET_DELAY 2015 2016 Some PHY like Intel LXT971A need extra delay after 2017 reset before any MII register access is possible. 2018 For such PHY, set this option to the usec delay 2019 required. (minimum 300usec for LXT971A) 2020 2021 CONFIG_PHY_CMD_DELAY (ppc4xx) 2022 2023 Some PHY like Intel LXT971A need extra delay after 2024 command issued before MII status register can be read 2025 2026- IP address: 2027 CONFIG_IPADDR 2028 2029 Define a default value for the IP address to use for 2030 the default Ethernet interface, in case this is not 2031 determined through e.g. bootp. 2032 (Environment variable "ipaddr") 2033 2034- Server IP address: 2035 CONFIG_SERVERIP 2036 2037 Defines a default value for the IP address of a TFTP 2038 server to contact when using the "tftboot" command. 2039 (Environment variable "serverip") 2040 2041 CONFIG_KEEP_SERVERADDR 2042 2043 Keeps the server's MAC address, in the env 'serveraddr' 2044 for passing to bootargs (like Linux's netconsole option) 2045 2046- Gateway IP address: 2047 CONFIG_GATEWAYIP 2048 2049 Defines a default value for the IP address of the 2050 default router where packets to other networks are 2051 sent to. 2052 (Environment variable "gatewayip") 2053 2054- Subnet mask: 2055 CONFIG_NETMASK 2056 2057 Defines a default value for the subnet mask (or 2058 routing prefix) which is used to determine if an IP 2059 address belongs to the local subnet or needs to be 2060 forwarded through a router. 2061 (Environment variable "netmask") 2062 2063- Multicast TFTP Mode: 2064 CONFIG_MCAST_TFTP 2065 2066 Defines whether you want to support multicast TFTP as per 2067 rfc-2090; for example to work with atftp. Lets lots of targets 2068 tftp down the same boot image concurrently. Note: the Ethernet 2069 driver in use must provide a function: mcast() to join/leave a 2070 multicast group. 2071 2072- BOOTP Recovery Mode: 2073 CONFIG_BOOTP_RANDOM_DELAY 2074 2075 If you have many targets in a network that try to 2076 boot using BOOTP, you may want to avoid that all 2077 systems send out BOOTP requests at precisely the same 2078 moment (which would happen for instance at recovery 2079 from a power failure, when all systems will try to 2080 boot, thus flooding the BOOTP server. Defining 2081 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be 2082 inserted before sending out BOOTP requests. The 2083 following delays are inserted then: 2084 2085 1st BOOTP request: delay 0 ... 1 sec 2086 2nd BOOTP request: delay 0 ... 2 sec 2087 3rd BOOTP request: delay 0 ... 4 sec 2088 4th and following 2089 BOOTP requests: delay 0 ... 8 sec 2090 2091 CONFIG_BOOTP_ID_CACHE_SIZE 2092 2093 BOOTP packets are uniquely identified using a 32-bit ID. The 2094 server will copy the ID from client requests to responses and 2095 U-Boot will use this to determine if it is the destination of 2096 an incoming response. Some servers will check that addresses 2097 aren't in use before handing them out (usually using an ARP 2098 ping) and therefore take up to a few hundred milliseconds to 2099 respond. Network congestion may also influence the time it 2100 takes for a response to make it back to the client. If that 2101 time is too long, U-Boot will retransmit requests. In order 2102 to allow earlier responses to still be accepted after these 2103 retransmissions, U-Boot's BOOTP client keeps a small cache of 2104 IDs. The CONFIG_BOOTP_ID_CACHE_SIZE controls the size of this 2105 cache. The default is to keep IDs for up to four outstanding 2106 requests. Increasing this will allow U-Boot to accept offers 2107 from a BOOTP client in networks with unusually high latency. 2108 2109- DHCP Advanced Options: 2110 You can fine tune the DHCP functionality by defining 2111 CONFIG_BOOTP_* symbols: 2112 2113 CONFIG_BOOTP_SUBNETMASK 2114 CONFIG_BOOTP_GATEWAY 2115 CONFIG_BOOTP_HOSTNAME 2116 CONFIG_BOOTP_NISDOMAIN 2117 CONFIG_BOOTP_BOOTPATH 2118 CONFIG_BOOTP_BOOTFILESIZE 2119 CONFIG_BOOTP_DNS 2120 CONFIG_BOOTP_DNS2 2121 CONFIG_BOOTP_SEND_HOSTNAME 2122 CONFIG_BOOTP_NTPSERVER 2123 CONFIG_BOOTP_TIMEOFFSET 2124 CONFIG_BOOTP_VENDOREX 2125 CONFIG_BOOTP_MAY_FAIL 2126 2127 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip 2128 environment variable, not the BOOTP server. 2129 2130 CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found 2131 after the configured retry count, the call will fail 2132 instead of starting over. This can be used to fail over 2133 to Link-local IP address configuration if the DHCP server 2134 is not available. 2135 2136 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS 2137 serverip from a DHCP server, it is possible that more 2138 than one DNS serverip is offered to the client. 2139 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS 2140 serverip will be stored in the additional environment 2141 variable "dnsip2". The first DNS serverip is always 2142 stored in the variable "dnsip", when CONFIG_BOOTP_DNS 2143 is defined. 2144 2145 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable 2146 to do a dynamic update of a DNS server. To do this, they 2147 need the hostname of the DHCP requester. 2148 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content 2149 of the "hostname" environment variable is passed as 2150 option 12 to the DHCP server. 2151 2152 CONFIG_BOOTP_DHCP_REQUEST_DELAY 2153 2154 A 32bit value in microseconds for a delay between 2155 receiving a "DHCP Offer" and sending the "DHCP Request". 2156 This fixes a problem with certain DHCP servers that don't 2157 respond 100% of the time to a "DHCP request". E.g. On an 2158 AT91RM9200 processor running at 180MHz, this delay needed 2159 to be *at least* 15,000 usec before a Windows Server 2003 2160 DHCP server would reply 100% of the time. I recommend at 2161 least 50,000 usec to be safe. The alternative is to hope 2162 that one of the retries will be successful but note that 2163 the DHCP timeout and retry process takes a longer than 2164 this delay. 2165 2166 - Link-local IP address negotiation: 2167 Negotiate with other link-local clients on the local network 2168 for an address that doesn't require explicit configuration. 2169 This is especially useful if a DHCP server cannot be guaranteed 2170 to exist in all environments that the device must operate. 2171 2172 See doc/README.link-local for more information. 2173 2174 - CDP Options: 2175 CONFIG_CDP_DEVICE_ID 2176 2177 The device id used in CDP trigger frames. 2178 2179 CONFIG_CDP_DEVICE_ID_PREFIX 2180 2181 A two character string which is prefixed to the MAC address 2182 of the device. 2183 2184 CONFIG_CDP_PORT_ID 2185 2186 A printf format string which contains the ascii name of 2187 the port. Normally is set to "eth%d" which sets 2188 eth0 for the first Ethernet, eth1 for the second etc. 2189 2190 CONFIG_CDP_CAPABILITIES 2191 2192 A 32bit integer which indicates the device capabilities; 2193 0x00000010 for a normal host which does not forwards. 2194 2195 CONFIG_CDP_VERSION 2196 2197 An ascii string containing the version of the software. 2198 2199 CONFIG_CDP_PLATFORM 2200 2201 An ascii string containing the name of the platform. 2202 2203 CONFIG_CDP_TRIGGER 2204 2205 A 32bit integer sent on the trigger. 2206 2207 CONFIG_CDP_POWER_CONSUMPTION 2208 2209 A 16bit integer containing the power consumption of the 2210 device in .1 of milliwatts. 2211 2212 CONFIG_CDP_APPLIANCE_VLAN_TYPE 2213 2214 A byte containing the id of the VLAN. 2215 2216- Status LED: CONFIG_STATUS_LED 2217 2218 Several configurations allow to display the current 2219 status using a LED. For instance, the LED will blink 2220 fast while running U-Boot code, stop blinking as 2221 soon as a reply to a BOOTP request was received, and 2222 start blinking slow once the Linux kernel is running 2223 (supported by a status LED driver in the Linux 2224 kernel). Defining CONFIG_STATUS_LED enables this 2225 feature in U-Boot. 2226 2227 Additional options: 2228 2229 CONFIG_GPIO_LED 2230 The status LED can be connected to a GPIO pin. 2231 In such cases, the gpio_led driver can be used as a 2232 status LED backend implementation. Define CONFIG_GPIO_LED 2233 to include the gpio_led driver in the U-Boot binary. 2234 2235 CONFIG_GPIO_LED_INVERTED_TABLE 2236 Some GPIO connected LEDs may have inverted polarity in which 2237 case the GPIO high value corresponds to LED off state and 2238 GPIO low value corresponds to LED on state. 2239 In such cases CONFIG_GPIO_LED_INVERTED_TABLE may be defined 2240 with a list of GPIO LEDs that have inverted polarity. 2241 2242- CAN Support: CONFIG_CAN_DRIVER 2243 2244 Defining CONFIG_CAN_DRIVER enables CAN driver support 2245 on those systems that support this (optional) 2246 feature, like the TQM8xxL modules. 2247 2248- I2C Support: CONFIG_SYS_I2C 2249 2250 This enable the NEW i2c subsystem, and will allow you to use 2251 i2c commands at the u-boot command line (as long as you set 2252 CONFIG_CMD_I2C in CONFIG_COMMANDS) and communicate with i2c 2253 based realtime clock chips or other i2c devices. See 2254 common/cmd_i2c.c for a description of the command line 2255 interface. 2256 2257 ported i2c driver to the new framework: 2258 - drivers/i2c/soft_i2c.c: 2259 - activate first bus with CONFIG_SYS_I2C_SOFT define 2260 CONFIG_SYS_I2C_SOFT_SPEED and CONFIG_SYS_I2C_SOFT_SLAVE 2261 for defining speed and slave address 2262 - activate second bus with I2C_SOFT_DECLARATIONS2 define 2263 CONFIG_SYS_I2C_SOFT_SPEED_2 and CONFIG_SYS_I2C_SOFT_SLAVE_2 2264 for defining speed and slave address 2265 - activate third bus with I2C_SOFT_DECLARATIONS3 define 2266 CONFIG_SYS_I2C_SOFT_SPEED_3 and CONFIG_SYS_I2C_SOFT_SLAVE_3 2267 for defining speed and slave address 2268 - activate fourth bus with I2C_SOFT_DECLARATIONS4 define 2269 CONFIG_SYS_I2C_SOFT_SPEED_4 and CONFIG_SYS_I2C_SOFT_SLAVE_4 2270 for defining speed and slave address 2271 2272 - drivers/i2c/fsl_i2c.c: 2273 - activate i2c driver with CONFIG_SYS_I2C_FSL 2274 define CONFIG_SYS_FSL_I2C_OFFSET for setting the register 2275 offset CONFIG_SYS_FSL_I2C_SPEED for the i2c speed and 2276 CONFIG_SYS_FSL_I2C_SLAVE for the slave addr of the first 2277 bus. 2278 - If your board supports a second fsl i2c bus, define 2279 CONFIG_SYS_FSL_I2C2_OFFSET for the register offset 2280 CONFIG_SYS_FSL_I2C2_SPEED for the speed and 2281 CONFIG_SYS_FSL_I2C2_SLAVE for the slave address of the 2282 second bus. 2283 2284 - drivers/i2c/tegra_i2c.c: 2285 - activate this driver with CONFIG_SYS_I2C_TEGRA 2286 - This driver adds 4 i2c buses with a fix speed from 2287 100000 and the slave addr 0! 2288 2289 - drivers/i2c/ppc4xx_i2c.c 2290 - activate this driver with CONFIG_SYS_I2C_PPC4XX 2291 - CONFIG_SYS_I2C_PPC4XX_CH0 activate hardware channel 0 2292 - CONFIG_SYS_I2C_PPC4XX_CH1 activate hardware channel 1 2293 2294 - drivers/i2c/i2c_mxc.c 2295 - activate this driver with CONFIG_SYS_I2C_MXC 2296 - enable bus 1 with CONFIG_SYS_I2C_MXC_I2C1 2297 - enable bus 2 with CONFIG_SYS_I2C_MXC_I2C2 2298 - enable bus 3 with CONFIG_SYS_I2C_MXC_I2C3 2299 - enable bus 4 with CONFIG_SYS_I2C_MXC_I2C4 2300 - define speed for bus 1 with CONFIG_SYS_MXC_I2C1_SPEED 2301 - define slave for bus 1 with CONFIG_SYS_MXC_I2C1_SLAVE 2302 - define speed for bus 2 with CONFIG_SYS_MXC_I2C2_SPEED 2303 - define slave for bus 2 with CONFIG_SYS_MXC_I2C2_SLAVE 2304 - define speed for bus 3 with CONFIG_SYS_MXC_I2C3_SPEED 2305 - define slave for bus 3 with CONFIG_SYS_MXC_I2C3_SLAVE 2306 - define speed for bus 4 with CONFIG_SYS_MXC_I2C4_SPEED 2307 - define slave for bus 4 with CONFIG_SYS_MXC_I2C4_SLAVE 2308 If those defines are not set, default value is 100000 2309 for speed, and 0 for slave. 2310 2311 - drivers/i2c/rcar_i2c.c: 2312 - activate this driver with CONFIG_SYS_I2C_RCAR 2313 - This driver adds 4 i2c buses 2314 2315 - CONFIG_SYS_RCAR_I2C0_BASE for setting the register channel 0 2316 - CONFIG_SYS_RCAR_I2C0_SPEED for for the speed channel 0 2317 - CONFIG_SYS_RCAR_I2C1_BASE for setting the register channel 1 2318 - CONFIG_SYS_RCAR_I2C1_SPEED for for the speed channel 1 2319 - CONFIG_SYS_RCAR_I2C2_BASE for setting the register channel 2 2320 - CONFIG_SYS_RCAR_I2C2_SPEED for for the speed channel 2 2321 - CONFIG_SYS_RCAR_I2C3_BASE for setting the register channel 3 2322 - CONFIG_SYS_RCAR_I2C3_SPEED for for the speed channel 3 2323 - CONFIF_SYS_RCAR_I2C_NUM_CONTROLLERS for number of i2c buses 2324 2325 - drivers/i2c/sh_i2c.c: 2326 - activate this driver with CONFIG_SYS_I2C_SH 2327 - This driver adds from 2 to 5 i2c buses 2328 2329 - CONFIG_SYS_I2C_SH_BASE0 for setting the register channel 0 2330 - CONFIG_SYS_I2C_SH_SPEED0 for for the speed channel 0 2331 - CONFIG_SYS_I2C_SH_BASE1 for setting the register channel 1 2332 - CONFIG_SYS_I2C_SH_SPEED1 for for the speed channel 1 2333 - CONFIG_SYS_I2C_SH_BASE2 for setting the register channel 2 2334 - CONFIG_SYS_I2C_SH_SPEED2 for for the speed channel 2 2335 - CONFIG_SYS_I2C_SH_BASE3 for setting the register channel 3 2336 - CONFIG_SYS_I2C_SH_SPEED3 for for the speed channel 3 2337 - CONFIG_SYS_I2C_SH_BASE4 for setting the register channel 4 2338 - CONFIG_SYS_I2C_SH_SPEED4 for for the speed channel 4 2339 - CONFIG_SYS_I2C_SH_BASE5 for setting the register channel 5 2340 - CONFIG_SYS_I2C_SH_SPEED5 for for the speed channel 5 2341 - CONFIG_SYS_I2C_SH_NUM_CONTROLLERS for number of i2c buses 2342 2343 - drivers/i2c/omap24xx_i2c.c 2344 - activate this driver with CONFIG_SYS_I2C_OMAP24XX 2345 - CONFIG_SYS_OMAP24_I2C_SPEED speed channel 0 2346 - CONFIG_SYS_OMAP24_I2C_SLAVE slave addr channel 0 2347 - CONFIG_SYS_OMAP24_I2C_SPEED1 speed channel 1 2348 - CONFIG_SYS_OMAP24_I2C_SLAVE1 slave addr channel 1 2349 - CONFIG_SYS_OMAP24_I2C_SPEED2 speed channel 2 2350 - CONFIG_SYS_OMAP24_I2C_SLAVE2 slave addr channel 2 2351 - CONFIG_SYS_OMAP24_I2C_SPEED3 speed channel 3 2352 - CONFIG_SYS_OMAP24_I2C_SLAVE3 slave addr channel 3 2353 - CONFIG_SYS_OMAP24_I2C_SPEED4 speed channel 4 2354 - CONFIG_SYS_OMAP24_I2C_SLAVE4 slave addr channel 4 2355 2356 - drivers/i2c/zynq_i2c.c 2357 - activate this driver with CONFIG_SYS_I2C_ZYNQ 2358 - set CONFIG_SYS_I2C_ZYNQ_SPEED for speed setting 2359 - set CONFIG_SYS_I2C_ZYNQ_SLAVE for slave addr 2360 2361 - drivers/i2c/s3c24x0_i2c.c: 2362 - activate this driver with CONFIG_SYS_I2C_S3C24X0 2363 - This driver adds i2c buses (11 for Exynos5250, Exynos5420 2364 9 i2c buses for Exynos4 and 1 for S3C24X0 SoCs from Samsung) 2365 with a fix speed from 100000 and the slave addr 0! 2366 2367 - drivers/i2c/ihs_i2c.c 2368 - activate this driver with CONFIG_SYS_I2C_IHS 2369 - CONFIG_SYS_I2C_IHS_CH0 activate hardware channel 0 2370 - CONFIG_SYS_I2C_IHS_SPEED_0 speed channel 0 2371 - CONFIG_SYS_I2C_IHS_SLAVE_0 slave addr channel 0 2372 - CONFIG_SYS_I2C_IHS_CH1 activate hardware channel 1 2373 - CONFIG_SYS_I2C_IHS_SPEED_1 speed channel 1 2374 - CONFIG_SYS_I2C_IHS_SLAVE_1 slave addr channel 1 2375 - CONFIG_SYS_I2C_IHS_CH2 activate hardware channel 2 2376 - CONFIG_SYS_I2C_IHS_SPEED_2 speed channel 2 2377 - CONFIG_SYS_I2C_IHS_SLAVE_2 slave addr channel 2 2378 - CONFIG_SYS_I2C_IHS_CH3 activate hardware channel 3 2379 - CONFIG_SYS_I2C_IHS_SPEED_3 speed channel 3 2380 - CONFIG_SYS_I2C_IHS_SLAVE_3 slave addr channel 3 2381 - activate dual channel with CONFIG_SYS_I2C_IHS_DUAL 2382 - CONFIG_SYS_I2C_IHS_SPEED_0_1 speed channel 0_1 2383 - CONFIG_SYS_I2C_IHS_SLAVE_0_1 slave addr channel 0_1 2384 - CONFIG_SYS_I2C_IHS_SPEED_1_1 speed channel 1_1 2385 - CONFIG_SYS_I2C_IHS_SLAVE_1_1 slave addr channel 1_1 2386 - CONFIG_SYS_I2C_IHS_SPEED_2_1 speed channel 2_1 2387 - CONFIG_SYS_I2C_IHS_SLAVE_2_1 slave addr channel 2_1 2388 - CONFIG_SYS_I2C_IHS_SPEED_3_1 speed channel 3_1 2389 - CONFIG_SYS_I2C_IHS_SLAVE_3_1 slave addr channel 3_1 2390 2391 additional defines: 2392 2393 CONFIG_SYS_NUM_I2C_BUSES 2394 Hold the number of i2c buses you want to use. If you 2395 don't use/have i2c muxes on your i2c bus, this 2396 is equal to CONFIG_SYS_NUM_I2C_ADAPTERS, and you can 2397 omit this define. 2398 2399 CONFIG_SYS_I2C_DIRECT_BUS 2400 define this, if you don't use i2c muxes on your hardware. 2401 if CONFIG_SYS_I2C_MAX_HOPS is not defined or == 0 you can 2402 omit this define. 2403 2404 CONFIG_SYS_I2C_MAX_HOPS 2405 define how many muxes are maximal consecutively connected 2406 on one i2c bus. If you not use i2c muxes, omit this 2407 define. 2408 2409 CONFIG_SYS_I2C_BUSES 2410 hold a list of buses you want to use, only used if 2411 CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example 2412 a board with CONFIG_SYS_I2C_MAX_HOPS = 1 and 2413 CONFIG_SYS_NUM_I2C_BUSES = 9: 2414 2415 CONFIG_SYS_I2C_BUSES {{0, {I2C_NULL_HOP}}, \ 2416 {0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \ 2417 {0, {{I2C_MUX_PCA9547, 0x70, 2}}}, \ 2418 {0, {{I2C_MUX_PCA9547, 0x70, 3}}}, \ 2419 {0, {{I2C_MUX_PCA9547, 0x70, 4}}}, \ 2420 {0, {{I2C_MUX_PCA9547, 0x70, 5}}}, \ 2421 {1, {I2C_NULL_HOP}}, \ 2422 {1, {{I2C_MUX_PCA9544, 0x72, 1}}}, \ 2423 {1, {{I2C_MUX_PCA9544, 0x72, 2}}}, \ 2424 } 2425 2426 which defines 2427 bus 0 on adapter 0 without a mux 2428 bus 1 on adapter 0 with a PCA9547 on address 0x70 port 1 2429 bus 2 on adapter 0 with a PCA9547 on address 0x70 port 2 2430 bus 3 on adapter 0 with a PCA9547 on address 0x70 port 3 2431 bus 4 on adapter 0 with a PCA9547 on address 0x70 port 4 2432 bus 5 on adapter 0 with a PCA9547 on address 0x70 port 5 2433 bus 6 on adapter 1 without a mux 2434 bus 7 on adapter 1 with a PCA9544 on address 0x72 port 1 2435 bus 8 on adapter 1 with a PCA9544 on address 0x72 port 2 2436 2437 If you do not have i2c muxes on your board, omit this define. 2438 2439- Legacy I2C Support: CONFIG_HARD_I2C 2440 2441 NOTE: It is intended to move drivers to CONFIG_SYS_I2C which 2442 provides the following compelling advantages: 2443 2444 - more than one i2c adapter is usable 2445 - approved multibus support 2446 - better i2c mux support 2447 2448 ** Please consider updating your I2C driver now. ** 2449 2450 These enable legacy I2C serial bus commands. Defining 2451 CONFIG_HARD_I2C will include the appropriate I2C driver 2452 for the selected CPU. 2453 2454 This will allow you to use i2c commands at the u-boot 2455 command line (as long as you set CONFIG_CMD_I2C in 2456 CONFIG_COMMANDS) and communicate with i2c based realtime 2457 clock chips. See common/cmd_i2c.c for a description of the 2458 command line interface. 2459 2460 CONFIG_HARD_I2C selects a hardware I2C controller. 2461 2462 There are several other quantities that must also be 2463 defined when you define CONFIG_HARD_I2C. 2464 2465 In both cases you will need to define CONFIG_SYS_I2C_SPEED 2466 to be the frequency (in Hz) at which you wish your i2c bus 2467 to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie 2468 the CPU's i2c node address). 2469 2470 Now, the u-boot i2c code for the mpc8xx 2471 (arch/powerpc/cpu/mpc8xx/i2c.c) sets the CPU up as a master node 2472 and so its address should therefore be cleared to 0 (See, 2473 eg, MPC823e User's Manual p.16-473). So, set 2474 CONFIG_SYS_I2C_SLAVE to 0. 2475 2476 CONFIG_SYS_I2C_INIT_MPC5XXX 2477 2478 When a board is reset during an i2c bus transfer 2479 chips might think that the current transfer is still 2480 in progress. Reset the slave devices by sending start 2481 commands until the slave device responds. 2482 2483 That's all that's required for CONFIG_HARD_I2C. 2484 2485 If you use the software i2c interface (CONFIG_SYS_I2C_SOFT) 2486 then the following macros need to be defined (examples are 2487 from include/configs/lwmon.h): 2488 2489 I2C_INIT 2490 2491 (Optional). Any commands necessary to enable the I2C 2492 controller or configure ports. 2493 2494 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL) 2495 2496 I2C_PORT 2497 2498 (Only for MPC8260 CPU). The I/O port to use (the code 2499 assumes both bits are on the same port). Valid values 2500 are 0..3 for ports A..D. 2501 2502 I2C_ACTIVE 2503 2504 The code necessary to make the I2C data line active 2505 (driven). If the data line is open collector, this 2506 define can be null. 2507 2508 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA) 2509 2510 I2C_TRISTATE 2511 2512 The code necessary to make the I2C data line tri-stated 2513 (inactive). If the data line is open collector, this 2514 define can be null. 2515 2516 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA) 2517 2518 I2C_READ 2519 2520 Code that returns true if the I2C data line is high, 2521 false if it is low. 2522 2523 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0) 2524 2525 I2C_SDA(bit) 2526 2527 If <bit> is true, sets the I2C data line high. If it 2528 is false, it clears it (low). 2529 2530 eg: #define I2C_SDA(bit) \ 2531 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \ 2532 else immr->im_cpm.cp_pbdat &= ~PB_SDA 2533 2534 I2C_SCL(bit) 2535 2536 If <bit> is true, sets the I2C clock line high. If it 2537 is false, it clears it (low). 2538 2539 eg: #define I2C_SCL(bit) \ 2540 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \ 2541 else immr->im_cpm.cp_pbdat &= ~PB_SCL 2542 2543 I2C_DELAY 2544 2545 This delay is invoked four times per clock cycle so this 2546 controls the rate of data transfer. The data rate thus 2547 is 1 / (I2C_DELAY * 4). Often defined to be something 2548 like: 2549 2550 #define I2C_DELAY udelay(2) 2551 2552 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA 2553 2554 If your arch supports the generic GPIO framework (asm/gpio.h), 2555 then you may alternatively define the two GPIOs that are to be 2556 used as SCL / SDA. Any of the previous I2C_xxx macros will 2557 have GPIO-based defaults assigned to them as appropriate. 2558 2559 You should define these to the GPIO value as given directly to 2560 the generic GPIO functions. 2561 2562 CONFIG_SYS_I2C_INIT_BOARD 2563 2564 When a board is reset during an i2c bus transfer 2565 chips might think that the current transfer is still 2566 in progress. On some boards it is possible to access 2567 the i2c SCLK line directly, either by using the 2568 processor pin as a GPIO or by having a second pin 2569 connected to the bus. If this option is defined a 2570 custom i2c_init_board() routine in boards/xxx/board.c 2571 is run early in the boot sequence. 2572 2573 CONFIG_SYS_I2C_BOARD_LATE_INIT 2574 2575 An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is 2576 defined a custom i2c_board_late_init() routine in 2577 boards/xxx/board.c is run AFTER the operations in i2c_init() 2578 is completed. This callpoint can be used to unreset i2c bus 2579 using CPU i2c controller register accesses for CPUs whose i2c 2580 controller provide such a method. It is called at the end of 2581 i2c_init() to allow i2c_init operations to setup the i2c bus 2582 controller on the CPU (e.g. setting bus speed & slave address). 2583 2584 CONFIG_I2CFAST (PPC405GP|PPC405EP only) 2585 2586 This option enables configuration of bi_iic_fast[] flags 2587 in u-boot bd_info structure based on u-boot environment 2588 variable "i2cfast". (see also i2cfast) 2589 2590 CONFIG_I2C_MULTI_BUS 2591 2592 This option allows the use of multiple I2C buses, each of which 2593 must have a controller. At any point in time, only one bus is 2594 active. To switch to a different bus, use the 'i2c dev' command. 2595 Note that bus numbering is zero-based. 2596 2597 CONFIG_SYS_I2C_NOPROBES 2598 2599 This option specifies a list of I2C devices that will be skipped 2600 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS 2601 is set, specify a list of bus-device pairs. Otherwise, specify 2602 a 1D array of device addresses 2603 2604 e.g. 2605 #undef CONFIG_I2C_MULTI_BUS 2606 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68} 2607 2608 will skip addresses 0x50 and 0x68 on a board with one I2C bus 2609 2610 #define CONFIG_I2C_MULTI_BUS 2611 #define CONFIG_SYS_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}} 2612 2613 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1 2614 2615 CONFIG_SYS_SPD_BUS_NUM 2616 2617 If defined, then this indicates the I2C bus number for DDR SPD. 2618 If not defined, then U-Boot assumes that SPD is on I2C bus 0. 2619 2620 CONFIG_SYS_RTC_BUS_NUM 2621 2622 If defined, then this indicates the I2C bus number for the RTC. 2623 If not defined, then U-Boot assumes that RTC is on I2C bus 0. 2624 2625 CONFIG_SYS_DTT_BUS_NUM 2626 2627 If defined, then this indicates the I2C bus number for the DTT. 2628 If not defined, then U-Boot assumes that DTT is on I2C bus 0. 2629 2630 CONFIG_SYS_I2C_DTT_ADDR: 2631 2632 If defined, specifies the I2C address of the DTT device. 2633 If not defined, then U-Boot uses predefined value for 2634 specified DTT device. 2635 2636 CONFIG_SOFT_I2C_READ_REPEATED_START 2637 2638 defining this will force the i2c_read() function in 2639 the soft_i2c driver to perform an I2C repeated start 2640 between writing the address pointer and reading the 2641 data. If this define is omitted the default behaviour 2642 of doing a stop-start sequence will be used. Most I2C 2643 devices can use either method, but some require one or 2644 the other. 2645 2646- SPI Support: CONFIG_SPI 2647 2648 Enables SPI driver (so far only tested with 2649 SPI EEPROM, also an instance works with Crystal A/D and 2650 D/As on the SACSng board) 2651 2652 CONFIG_SH_SPI 2653 2654 Enables the driver for SPI controller on SuperH. Currently 2655 only SH7757 is supported. 2656 2657 CONFIG_SOFT_SPI 2658 2659 Enables a software (bit-bang) SPI driver rather than 2660 using hardware support. This is a general purpose 2661 driver that only requires three general I/O port pins 2662 (two outputs, one input) to function. If this is 2663 defined, the board configuration must define several 2664 SPI configuration items (port pins to use, etc). For 2665 an example, see include/configs/sacsng.h. 2666 2667 CONFIG_HARD_SPI 2668 2669 Enables a hardware SPI driver for general-purpose reads 2670 and writes. As with CONFIG_SOFT_SPI, the board configuration 2671 must define a list of chip-select function pointers. 2672 Currently supported on some MPC8xxx processors. For an 2673 example, see include/configs/mpc8349emds.h. 2674 2675 CONFIG_MXC_SPI 2676 2677 Enables the driver for the SPI controllers on i.MX and MXC 2678 SoCs. Currently i.MX31/35/51 are supported. 2679 2680 CONFIG_SYS_SPI_MXC_WAIT 2681 Timeout for waiting until spi transfer completed. 2682 default: (CONFIG_SYS_HZ/100) /* 10 ms */ 2683 2684- FPGA Support: CONFIG_FPGA 2685 2686 Enables FPGA subsystem. 2687 2688 CONFIG_FPGA_<vendor> 2689 2690 Enables support for specific chip vendors. 2691 (ALTERA, XILINX) 2692 2693 CONFIG_FPGA_<family> 2694 2695 Enables support for FPGA family. 2696 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX) 2697 2698 CONFIG_FPGA_COUNT 2699 2700 Specify the number of FPGA devices to support. 2701 2702 CONFIG_CMD_FPGA_LOADMK 2703 2704 Enable support for fpga loadmk command 2705 2706 CONFIG_CMD_FPGA_LOADP 2707 2708 Enable support for fpga loadp command - load partial bitstream 2709 2710 CONFIG_CMD_FPGA_LOADBP 2711 2712 Enable support for fpga loadbp command - load partial bitstream 2713 (Xilinx only) 2714 2715 CONFIG_SYS_FPGA_PROG_FEEDBACK 2716 2717 Enable printing of hash marks during FPGA configuration. 2718 2719 CONFIG_SYS_FPGA_CHECK_BUSY 2720 2721 Enable checks on FPGA configuration interface busy 2722 status by the configuration function. This option 2723 will require a board or device specific function to 2724 be written. 2725 2726 CONFIG_FPGA_DELAY 2727 2728 If defined, a function that provides delays in the FPGA 2729 configuration driver. 2730 2731 CONFIG_SYS_FPGA_CHECK_CTRLC 2732 Allow Control-C to interrupt FPGA configuration 2733 2734 CONFIG_SYS_FPGA_CHECK_ERROR 2735 2736 Check for configuration errors during FPGA bitfile 2737 loading. For example, abort during Virtex II 2738 configuration if the INIT_B line goes low (which 2739 indicated a CRC error). 2740 2741 CONFIG_SYS_FPGA_WAIT_INIT 2742 2743 Maximum time to wait for the INIT_B line to de-assert 2744 after PROB_B has been de-asserted during a Virtex II 2745 FPGA configuration sequence. The default time is 500 2746 ms. 2747 2748 CONFIG_SYS_FPGA_WAIT_BUSY 2749 2750 Maximum time to wait for BUSY to de-assert during 2751 Virtex II FPGA configuration. The default is 5 ms. 2752 2753 CONFIG_SYS_FPGA_WAIT_CONFIG 2754 2755 Time to wait after FPGA configuration. The default is 2756 200 ms. 2757 2758- Configuration Management: 2759 CONFIG_BUILD_TARGET 2760 2761 Some SoCs need special image types (e.g. U-Boot binary 2762 with a special header) as build targets. By defining 2763 CONFIG_BUILD_TARGET in the SoC / board header, this 2764 special image will be automatically built upon calling 2765 make / MAKEALL. 2766 2767 CONFIG_IDENT_STRING 2768 2769 If defined, this string will be added to the U-Boot 2770 version information (U_BOOT_VERSION) 2771 2772- Vendor Parameter Protection: 2773 2774 U-Boot considers the values of the environment 2775 variables "serial#" (Board Serial Number) and 2776 "ethaddr" (Ethernet Address) to be parameters that 2777 are set once by the board vendor / manufacturer, and 2778 protects these variables from casual modification by 2779 the user. Once set, these variables are read-only, 2780 and write or delete attempts are rejected. You can 2781 change this behaviour: 2782 2783 If CONFIG_ENV_OVERWRITE is #defined in your config 2784 file, the write protection for vendor parameters is 2785 completely disabled. Anybody can change or delete 2786 these parameters. 2787 2788 Alternatively, if you define _both_ an ethaddr in the 2789 default env _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default 2790 Ethernet address is installed in the environment, 2791 which can be changed exactly ONCE by the user. [The 2792 serial# is unaffected by this, i. e. it remains 2793 read-only.] 2794 2795 The same can be accomplished in a more flexible way 2796 for any variable by configuring the type of access 2797 to allow for those variables in the ".flags" variable 2798 or define CONFIG_ENV_FLAGS_LIST_STATIC. 2799 2800- Protected RAM: 2801 CONFIG_PRAM 2802 2803 Define this variable to enable the reservation of 2804 "protected RAM", i. e. RAM which is not overwritten 2805 by U-Boot. Define CONFIG_PRAM to hold the number of 2806 kB you want to reserve for pRAM. You can overwrite 2807 this default value by defining an environment 2808 variable "pram" to the number of kB you want to 2809 reserve. Note that the board info structure will 2810 still show the full amount of RAM. If pRAM is 2811 reserved, a new environment variable "mem" will 2812 automatically be defined to hold the amount of 2813 remaining RAM in a form that can be passed as boot 2814 argument to Linux, for instance like that: 2815 2816 setenv bootargs ... mem=\${mem} 2817 saveenv 2818 2819 This way you can tell Linux not to use this memory, 2820 either, which results in a memory region that will 2821 not be affected by reboots. 2822 2823 *WARNING* If your board configuration uses automatic 2824 detection of the RAM size, you must make sure that 2825 this memory test is non-destructive. So far, the 2826 following board configurations are known to be 2827 "pRAM-clean": 2828 2829 IVMS8, IVML24, SPD8xx, TQM8xxL, 2830 HERMES, IP860, RPXlite, LWMON, 2831 FLAGADM, TQM8260 2832 2833- Access to physical memory region (> 4GB) 2834 Some basic support is provided for operations on memory not 2835 normally accessible to U-Boot - e.g. some architectures 2836 support access to more than 4GB of memory on 32-bit 2837 machines using physical address extension or similar. 2838 Define CONFIG_PHYSMEM to access this basic support, which 2839 currently only supports clearing the memory. 2840 2841- Error Recovery: 2842 CONFIG_PANIC_HANG 2843 2844 Define this variable to stop the system in case of a 2845 fatal error, so that you have to reset it manually. 2846 This is probably NOT a good idea for an embedded 2847 system where you want the system to reboot 2848 automatically as fast as possible, but it may be 2849 useful during development since you can try to debug 2850 the conditions that lead to the situation. 2851 2852 CONFIG_NET_RETRY_COUNT 2853 2854 This variable defines the number of retries for 2855 network operations like ARP, RARP, TFTP, or BOOTP 2856 before giving up the operation. If not defined, a 2857 default value of 5 is used. 2858 2859 CONFIG_ARP_TIMEOUT 2860 2861 Timeout waiting for an ARP reply in milliseconds. 2862 2863 CONFIG_NFS_TIMEOUT 2864 2865 Timeout in milliseconds used in NFS protocol. 2866 If you encounter "ERROR: Cannot umount" in nfs command, 2867 try longer timeout such as 2868 #define CONFIG_NFS_TIMEOUT 10000UL 2869 2870- Command Interpreter: 2871 CONFIG_AUTO_COMPLETE 2872 2873 Enable auto completion of commands using TAB. 2874 2875 CONFIG_SYS_PROMPT_HUSH_PS2 2876 2877 This defines the secondary prompt string, which is 2878 printed when the command interpreter needs more input 2879 to complete a command. Usually "> ". 2880 2881 Note: 2882 2883 In the current implementation, the local variables 2884 space and global environment variables space are 2885 separated. Local variables are those you define by 2886 simply typing `name=value'. To access a local 2887 variable later on, you have write `$name' or 2888 `${name}'; to execute the contents of a variable 2889 directly type `$name' at the command prompt. 2890 2891 Global environment variables are those you use 2892 setenv/printenv to work with. To run a command stored 2893 in such a variable, you need to use the run command, 2894 and you must not use the '$' sign to access them. 2895 2896 To store commands and special characters in a 2897 variable, please use double quotation marks 2898 surrounding the whole text of the variable, instead 2899 of the backslashes before semicolons and special 2900 symbols. 2901 2902- Command Line Editing and History: 2903 CONFIG_CMDLINE_EDITING 2904 2905 Enable editing and History functions for interactive 2906 command line input operations 2907 2908- Command Line PS1/PS2 support: 2909 CONFIG_CMDLINE_PS_SUPPORT 2910 2911 Enable support for changing the command prompt string 2912 at run-time. Only static string is supported so far. 2913 The string is obtained from environment variables PS1 2914 and PS2. 2915 2916- Default Environment: 2917 CONFIG_EXTRA_ENV_SETTINGS 2918 2919 Define this to contain any number of null terminated 2920 strings (variable = value pairs) that will be part of 2921 the default environment compiled into the boot image. 2922 2923 For example, place something like this in your 2924 board's config file: 2925 2926 #define CONFIG_EXTRA_ENV_SETTINGS \ 2927 "myvar1=value1\0" \ 2928 "myvar2=value2\0" 2929 2930 Warning: This method is based on knowledge about the 2931 internal format how the environment is stored by the 2932 U-Boot code. This is NOT an official, exported 2933 interface! Although it is unlikely that this format 2934 will change soon, there is no guarantee either. 2935 You better know what you are doing here. 2936 2937 Note: overly (ab)use of the default environment is 2938 discouraged. Make sure to check other ways to preset 2939 the environment like the "source" command or the 2940 boot command first. 2941 2942 CONFIG_ENV_VARS_UBOOT_CONFIG 2943 2944 Define this in order to add variables describing the 2945 U-Boot build configuration to the default environment. 2946 These will be named arch, cpu, board, vendor, and soc. 2947 2948 Enabling this option will cause the following to be defined: 2949 2950 - CONFIG_SYS_ARCH 2951 - CONFIG_SYS_CPU 2952 - CONFIG_SYS_BOARD 2953 - CONFIG_SYS_VENDOR 2954 - CONFIG_SYS_SOC 2955 2956 CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG 2957 2958 Define this in order to add variables describing certain 2959 run-time determined information about the hardware to the 2960 environment. These will be named board_name, board_rev. 2961 2962 CONFIG_DELAY_ENVIRONMENT 2963 2964 Normally the environment is loaded when the board is 2965 initialised so that it is available to U-Boot. This inhibits 2966 that so that the environment is not available until 2967 explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL 2968 this is instead controlled by the value of 2969 /config/load-environment. 2970 2971- Parallel Flash support: 2972 CONFIG_SYS_NO_FLASH 2973 2974 Traditionally U-Boot was run on systems with parallel NOR 2975 flash. This option is used to disable support for parallel NOR 2976 flash. This option should be defined if the board does not have 2977 parallel flash. 2978 2979 If this option is not defined one of the generic flash drivers 2980 (e.g. CONFIG_FLASH_CFI_DRIVER or CONFIG_ST_SMI) must be 2981 selected or the board must provide an implementation of the 2982 flash API (see include/flash.h). 2983 2984- DataFlash Support: 2985 CONFIG_HAS_DATAFLASH 2986 2987 Defining this option enables DataFlash features and 2988 allows to read/write in Dataflash via the standard 2989 commands cp, md... 2990 2991- Serial Flash support 2992 CONFIG_CMD_SF 2993 2994 Defining this option enables SPI flash commands 2995 'sf probe/read/write/erase/update'. 2996 2997 Usage requires an initial 'probe' to define the serial 2998 flash parameters, followed by read/write/erase/update 2999 commands. 3000 3001 The following defaults may be provided by the platform 3002 to handle the common case when only a single serial 3003 flash is present on the system. 3004 3005 CONFIG_SF_DEFAULT_BUS Bus identifier 3006 CONFIG_SF_DEFAULT_CS Chip-select 3007 CONFIG_SF_DEFAULT_MODE (see include/spi.h) 3008 CONFIG_SF_DEFAULT_SPEED in Hz 3009 3010 CONFIG_CMD_SF_TEST 3011 3012 Define this option to include a destructive SPI flash 3013 test ('sf test'). 3014 3015 CONFIG_SF_DUAL_FLASH Dual flash memories 3016 3017 Define this option to use dual flash support where two flash 3018 memories can be connected with a given cs line. 3019 Currently Xilinx Zynq qspi supports these type of connections. 3020 3021- SystemACE Support: 3022 CONFIG_SYSTEMACE 3023 3024 Adding this option adds support for Xilinx SystemACE 3025 chips attached via some sort of local bus. The address 3026 of the chip must also be defined in the 3027 CONFIG_SYS_SYSTEMACE_BASE macro. For example: 3028 3029 #define CONFIG_SYSTEMACE 3030 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000 3031 3032 When SystemACE support is added, the "ace" device type 3033 becomes available to the fat commands, i.e. fatls. 3034 3035- TFTP Fixed UDP Port: 3036 CONFIG_TFTP_PORT 3037 3038 If this is defined, the environment variable tftpsrcp 3039 is used to supply the TFTP UDP source port value. 3040 If tftpsrcp isn't defined, the normal pseudo-random port 3041 number generator is used. 3042 3043 Also, the environment variable tftpdstp is used to supply 3044 the TFTP UDP destination port value. If tftpdstp isn't 3045 defined, the normal port 69 is used. 3046 3047 The purpose for tftpsrcp is to allow a TFTP server to 3048 blindly start the TFTP transfer using the pre-configured 3049 target IP address and UDP port. This has the effect of 3050 "punching through" the (Windows XP) firewall, allowing 3051 the remainder of the TFTP transfer to proceed normally. 3052 A better solution is to properly configure the firewall, 3053 but sometimes that is not allowed. 3054 3055- Hashing support: 3056 CONFIG_CMD_HASH 3057 3058 This enables a generic 'hash' command which can produce 3059 hashes / digests from a few algorithms (e.g. SHA1, SHA256). 3060 3061 CONFIG_HASH_VERIFY 3062 3063 Enable the hash verify command (hash -v). This adds to code 3064 size a little. 3065 3066 CONFIG_SHA1 - This option enables support of hashing using SHA1 3067 algorithm. The hash is calculated in software. 3068 CONFIG_SHA256 - This option enables support of hashing using 3069 SHA256 algorithm. The hash is calculated in software. 3070 CONFIG_SHA_HW_ACCEL - This option enables hardware acceleration 3071 for SHA1/SHA256 hashing. 3072 This affects the 'hash' command and also the 3073 hash_lookup_algo() function. 3074 CONFIG_SHA_PROG_HW_ACCEL - This option enables 3075 hardware-acceleration for SHA1/SHA256 progressive hashing. 3076 Data can be streamed in a block at a time and the hashing 3077 is performed in hardware. 3078 3079 Note: There is also a sha1sum command, which should perhaps 3080 be deprecated in favour of 'hash sha1'. 3081 3082- Freescale i.MX specific commands: 3083 CONFIG_CMD_HDMIDETECT 3084 This enables 'hdmidet' command which returns true if an 3085 HDMI monitor is detected. This command is i.MX 6 specific. 3086 3087 CONFIG_CMD_BMODE 3088 This enables the 'bmode' (bootmode) command for forcing 3089 a boot from specific media. 3090 3091 This is useful for forcing the ROM's usb downloader to 3092 activate upon a watchdog reset which is nice when iterating 3093 on U-Boot. Using the reset button or running bmode normal 3094 will set it back to normal. This command currently 3095 supports i.MX53 and i.MX6. 3096 3097- Signing support: 3098 CONFIG_RSA 3099 3100 This enables the RSA algorithm used for FIT image verification 3101 in U-Boot. See doc/uImage.FIT/signature.txt for more information. 3102 3103 The Modular Exponentiation algorithm in RSA is implemented using 3104 driver model. So CONFIG_DM needs to be enabled by default for this 3105 library to function. 3106 3107 The signing part is build into mkimage regardless of this 3108 option. The software based modular exponentiation is built into 3109 mkimage irrespective of this option. 3110 3111- bootcount support: 3112 CONFIG_BOOTCOUNT_LIMIT 3113 3114 This enables the bootcounter support, see: 3115 http://www.denx.de/wiki/DULG/UBootBootCountLimit 3116 3117 CONFIG_AT91SAM9XE 3118 enable special bootcounter support on at91sam9xe based boards. 3119 CONFIG_BLACKFIN 3120 enable special bootcounter support on blackfin based boards. 3121 CONFIG_SOC_DA8XX 3122 enable special bootcounter support on da850 based boards. 3123 CONFIG_BOOTCOUNT_RAM 3124 enable support for the bootcounter in RAM 3125 CONFIG_BOOTCOUNT_I2C 3126 enable support for the bootcounter on an i2c (like RTC) device. 3127 CONFIG_SYS_I2C_RTC_ADDR = i2c chip address 3128 CONFIG_SYS_BOOTCOUNT_ADDR = i2c addr which is used for 3129 the bootcounter. 3130 CONFIG_BOOTCOUNT_ALEN = address len 3131 3132- Show boot progress: 3133 CONFIG_SHOW_BOOT_PROGRESS 3134 3135 Defining this option allows to add some board- 3136 specific code (calling a user-provided function 3137 "show_boot_progress(int)") that enables you to show 3138 the system's boot progress on some display (for 3139 example, some LED's) on your board. At the moment, 3140 the following checkpoints are implemented: 3141 3142 3143Legacy uImage format: 3144 3145 Arg Where When 3146 1 common/cmd_bootm.c before attempting to boot an image 3147 -1 common/cmd_bootm.c Image header has bad magic number 3148 2 common/cmd_bootm.c Image header has correct magic number 3149 -2 common/cmd_bootm.c Image header has bad checksum 3150 3 common/cmd_bootm.c Image header has correct checksum 3151 -3 common/cmd_bootm.c Image data has bad checksum 3152 4 common/cmd_bootm.c Image data has correct checksum 3153 -4 common/cmd_bootm.c Image is for unsupported architecture 3154 5 common/cmd_bootm.c Architecture check OK 3155 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi) 3156 6 common/cmd_bootm.c Image Type check OK 3157 -6 common/cmd_bootm.c gunzip uncompression error 3158 -7 common/cmd_bootm.c Unimplemented compression type 3159 7 common/cmd_bootm.c Uncompression OK 3160 8 common/cmd_bootm.c No uncompress/copy overwrite error 3161 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX) 3162 3163 9 common/image.c Start initial ramdisk verification 3164 -10 common/image.c Ramdisk header has bad magic number 3165 -11 common/image.c Ramdisk header has bad checksum 3166 10 common/image.c Ramdisk header is OK 3167 -12 common/image.c Ramdisk data has bad checksum 3168 11 common/image.c Ramdisk data has correct checksum 3169 12 common/image.c Ramdisk verification complete, start loading 3170 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk) 3171 13 common/image.c Start multifile image verification 3172 14 common/image.c No initial ramdisk, no multifile, continue. 3173 3174 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS 3175 3176 -30 arch/powerpc/lib/board.c Fatal error, hang the system 3177 -31 post/post.c POST test failed, detected by post_output_backlog() 3178 -32 post/post.c POST test failed, detected by post_run_single() 3179 3180 34 common/cmd_doc.c before loading a Image from a DOC device 3181 -35 common/cmd_doc.c Bad usage of "doc" command 3182 35 common/cmd_doc.c correct usage of "doc" command 3183 -36 common/cmd_doc.c No boot device 3184 36 common/cmd_doc.c correct boot device 3185 -37 common/cmd_doc.c Unknown Chip ID on boot device 3186 37 common/cmd_doc.c correct chip ID found, device available 3187 -38 common/cmd_doc.c Read Error on boot device 3188 38 common/cmd_doc.c reading Image header from DOC device OK 3189 -39 common/cmd_doc.c Image header has bad magic number 3190 39 common/cmd_doc.c Image header has correct magic number 3191 -40 common/cmd_doc.c Error reading Image from DOC device 3192 40 common/cmd_doc.c Image header has correct magic number 3193 41 common/cmd_ide.c before loading a Image from a IDE device 3194 -42 common/cmd_ide.c Bad usage of "ide" command 3195 42 common/cmd_ide.c correct usage of "ide" command 3196 -43 common/cmd_ide.c No boot device 3197 43 common/cmd_ide.c boot device found 3198 -44 common/cmd_ide.c Device not available 3199 44 common/cmd_ide.c Device available 3200 -45 common/cmd_ide.c wrong partition selected 3201 45 common/cmd_ide.c partition selected 3202 -46 common/cmd_ide.c Unknown partition table 3203 46 common/cmd_ide.c valid partition table found 3204 -47 common/cmd_ide.c Invalid partition type 3205 47 common/cmd_ide.c correct partition type 3206 -48 common/cmd_ide.c Error reading Image Header on boot device 3207 48 common/cmd_ide.c reading Image Header from IDE device OK 3208 -49 common/cmd_ide.c Image header has bad magic number 3209 49 common/cmd_ide.c Image header has correct magic number 3210 -50 common/cmd_ide.c Image header has bad checksum 3211 50 common/cmd_ide.c Image header has correct checksum 3212 -51 common/cmd_ide.c Error reading Image from IDE device 3213 51 common/cmd_ide.c reading Image from IDE device OK 3214 52 common/cmd_nand.c before loading a Image from a NAND device 3215 -53 common/cmd_nand.c Bad usage of "nand" command 3216 53 common/cmd_nand.c correct usage of "nand" command 3217 -54 common/cmd_nand.c No boot device 3218 54 common/cmd_nand.c boot device found 3219 -55 common/cmd_nand.c Unknown Chip ID on boot device 3220 55 common/cmd_nand.c correct chip ID found, device available 3221 -56 common/cmd_nand.c Error reading Image Header on boot device 3222 56 common/cmd_nand.c reading Image Header from NAND device OK 3223 -57 common/cmd_nand.c Image header has bad magic number 3224 57 common/cmd_nand.c Image header has correct magic number 3225 -58 common/cmd_nand.c Error reading Image from NAND device 3226 58 common/cmd_nand.c reading Image from NAND device OK 3227 3228 -60 common/env_common.c Environment has a bad CRC, using default 3229 3230 64 net/eth.c starting with Ethernet configuration. 3231 -64 net/eth.c no Ethernet found. 3232 65 net/eth.c Ethernet found. 3233 3234 -80 common/cmd_net.c usage wrong 3235 80 common/cmd_net.c before calling net_loop() 3236 -81 common/cmd_net.c some error in net_loop() occurred 3237 81 common/cmd_net.c net_loop() back without error 3238 -82 common/cmd_net.c size == 0 (File with size 0 loaded) 3239 82 common/cmd_net.c trying automatic boot 3240 83 common/cmd_net.c running "source" command 3241 -83 common/cmd_net.c some error in automatic boot or "source" command 3242 84 common/cmd_net.c end without errors 3243 3244FIT uImage format: 3245 3246 Arg Where When 3247 100 common/cmd_bootm.c Kernel FIT Image has correct format 3248 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format 3249 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration 3250 -101 common/cmd_bootm.c Can't get configuration for kernel subimage 3251 102 common/cmd_bootm.c Kernel unit name specified 3252 -103 common/cmd_bootm.c Can't get kernel subimage node offset 3253 103 common/cmd_bootm.c Found configuration node 3254 104 common/cmd_bootm.c Got kernel subimage node offset 3255 -104 common/cmd_bootm.c Kernel subimage hash verification failed 3256 105 common/cmd_bootm.c Kernel subimage hash verification OK 3257 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture 3258 106 common/cmd_bootm.c Architecture check OK 3259 -106 common/cmd_bootm.c Kernel subimage has wrong type 3260 107 common/cmd_bootm.c Kernel subimage type OK 3261 -107 common/cmd_bootm.c Can't get kernel subimage data/size 3262 108 common/cmd_bootm.c Got kernel subimage data/size 3263 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT) 3264 -109 common/cmd_bootm.c Can't get kernel subimage type 3265 -110 common/cmd_bootm.c Can't get kernel subimage comp 3266 -111 common/cmd_bootm.c Can't get kernel subimage os 3267 -112 common/cmd_bootm.c Can't get kernel subimage load address 3268 -113 common/cmd_bootm.c Image uncompress/copy overwrite error 3269 3270 120 common/image.c Start initial ramdisk verification 3271 -120 common/image.c Ramdisk FIT image has incorrect format 3272 121 common/image.c Ramdisk FIT image has correct format 3273 122 common/image.c No ramdisk subimage unit name, using configuration 3274 -122 common/image.c Can't get configuration for ramdisk subimage 3275 123 common/image.c Ramdisk unit name specified 3276 -124 common/image.c Can't get ramdisk subimage node offset 3277 125 common/image.c Got ramdisk subimage node offset 3278 -125 common/image.c Ramdisk subimage hash verification failed 3279 126 common/image.c Ramdisk subimage hash verification OK 3280 -126 common/image.c Ramdisk subimage for unsupported architecture 3281 127 common/image.c Architecture check OK 3282 -127 common/image.c Can't get ramdisk subimage data/size 3283 128 common/image.c Got ramdisk subimage data/size 3284 129 common/image.c Can't get ramdisk load address 3285 -129 common/image.c Got ramdisk load address 3286 3287 -130 common/cmd_doc.c Incorrect FIT image format 3288 131 common/cmd_doc.c FIT image format OK 3289 3290 -140 common/cmd_ide.c Incorrect FIT image format 3291 141 common/cmd_ide.c FIT image format OK 3292 3293 -150 common/cmd_nand.c Incorrect FIT image format 3294 151 common/cmd_nand.c FIT image format OK 3295 3296- legacy image format: 3297 CONFIG_IMAGE_FORMAT_LEGACY 3298 enables the legacy image format support in U-Boot. 3299 3300 Default: 3301 enabled if CONFIG_FIT_SIGNATURE is not defined. 3302 3303 CONFIG_DISABLE_IMAGE_LEGACY 3304 disable the legacy image format 3305 3306 This define is introduced, as the legacy image format is 3307 enabled per default for backward compatibility. 3308 3309- FIT image support: 3310 CONFIG_FIT 3311 Enable support for the FIT uImage format. 3312 3313 CONFIG_FIT_BEST_MATCH 3314 When no configuration is explicitly selected, default to the 3315 one whose fdt's compatibility field best matches that of 3316 U-Boot itself. A match is considered "best" if it matches the 3317 most specific compatibility entry of U-Boot's fdt's root node. 3318 The order of entries in the configuration's fdt is ignored. 3319 3320 CONFIG_FIT_SIGNATURE 3321 This option enables signature verification of FIT uImages, 3322 using a hash signed and verified using RSA. If 3323 CONFIG_SHA_PROG_HW_ACCEL is defined, i.e support for progressive 3324 hashing is available using hardware, RSA library will use it. 3325 See doc/uImage.FIT/signature.txt for more details. 3326 3327 WARNING: When relying on signed FIT images with required 3328 signature check the legacy image format is default 3329 disabled. If a board need legacy image format support 3330 enable this through CONFIG_IMAGE_FORMAT_LEGACY 3331 3332 CONFIG_FIT_DISABLE_SHA256 3333 Supporting SHA256 hashes has quite an impact on binary size. 3334 For constrained systems sha256 hash support can be disabled 3335 with this option. 3336 3337- Standalone program support: 3338 CONFIG_STANDALONE_LOAD_ADDR 3339 3340 This option defines a board specific value for the 3341 address where standalone program gets loaded, thus 3342 overwriting the architecture dependent default 3343 settings. 3344 3345- Frame Buffer Address: 3346 CONFIG_FB_ADDR 3347 3348 Define CONFIG_FB_ADDR if you want to use specific 3349 address for frame buffer. This is typically the case 3350 when using a graphics controller has separate video 3351 memory. U-Boot will then place the frame buffer at 3352 the given address instead of dynamically reserving it 3353 in system RAM by calling lcd_setmem(), which grabs 3354 the memory for the frame buffer depending on the 3355 configured panel size. 3356 3357 Please see board_init_f function. 3358 3359- Automatic software updates via TFTP server 3360 CONFIG_UPDATE_TFTP 3361 CONFIG_UPDATE_TFTP_CNT_MAX 3362 CONFIG_UPDATE_TFTP_MSEC_MAX 3363 3364 These options enable and control the auto-update feature; 3365 for a more detailed description refer to doc/README.update. 3366 3367- MTD Support (mtdparts command, UBI support) 3368 CONFIG_MTD_DEVICE 3369 3370 Adds the MTD device infrastructure from the Linux kernel. 3371 Needed for mtdparts command support. 3372 3373 CONFIG_MTD_PARTITIONS 3374 3375 Adds the MTD partitioning infrastructure from the Linux 3376 kernel. Needed for UBI support. 3377 3378- UBI support 3379 CONFIG_CMD_UBI 3380 3381 Adds commands for interacting with MTD partitions formatted 3382 with the UBI flash translation layer 3383 3384 Requires also defining CONFIG_RBTREE 3385 3386 CONFIG_UBI_SILENCE_MSG 3387 3388 Make the verbose messages from UBI stop printing. This leaves 3389 warnings and errors enabled. 3390 3391 3392 CONFIG_MTD_UBI_WL_THRESHOLD 3393 This parameter defines the maximum difference between the highest 3394 erase counter value and the lowest erase counter value of eraseblocks 3395 of UBI devices. When this threshold is exceeded, UBI starts performing 3396 wear leveling by means of moving data from eraseblock with low erase 3397 counter to eraseblocks with high erase counter. 3398 3399 The default value should be OK for SLC NAND flashes, NOR flashes and 3400 other flashes which have eraseblock life-cycle 100000 or more. 3401 However, in case of MLC NAND flashes which typically have eraseblock 3402 life-cycle less than 10000, the threshold should be lessened (e.g., 3403 to 128 or 256, although it does not have to be power of 2). 3404 3405 default: 4096 3406 3407 CONFIG_MTD_UBI_BEB_LIMIT 3408 This option specifies the maximum bad physical eraseblocks UBI 3409 expects on the MTD device (per 1024 eraseblocks). If the 3410 underlying flash does not admit of bad eraseblocks (e.g. NOR 3411 flash), this value is ignored. 3412 3413 NAND datasheets often specify the minimum and maximum NVM 3414 (Number of Valid Blocks) for the flashes' endurance lifetime. 3415 The maximum expected bad eraseblocks per 1024 eraseblocks 3416 then can be calculated as "1024 * (1 - MinNVB / MaxNVB)", 3417 which gives 20 for most NANDs (MaxNVB is basically the total 3418 count of eraseblocks on the chip). 3419 3420 To put it differently, if this value is 20, UBI will try to 3421 reserve about 1.9% of physical eraseblocks for bad blocks 3422 handling. And that will be 1.9% of eraseblocks on the entire 3423 NAND chip, not just the MTD partition UBI attaches. This means 3424 that if you have, say, a NAND flash chip admits maximum 40 bad 3425 eraseblocks, and it is split on two MTD partitions of the same 3426 size, UBI will reserve 40 eraseblocks when attaching a 3427 partition. 3428 3429 default: 20 3430 3431 CONFIG_MTD_UBI_FASTMAP 3432 Fastmap is a mechanism which allows attaching an UBI device 3433 in nearly constant time. Instead of scanning the whole MTD device it 3434 only has to locate a checkpoint (called fastmap) on the device. 3435 The on-flash fastmap contains all information needed to attach 3436 the device. Using fastmap makes only sense on large devices where 3437 attaching by scanning takes long. UBI will not automatically install 3438 a fastmap on old images, but you can set the UBI parameter 3439 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT to 1 if you want so. Please note 3440 that fastmap-enabled images are still usable with UBI implementations 3441 without fastmap support. On typical flash devices the whole fastmap 3442 fits into one PEB. UBI will reserve PEBs to hold two fastmaps. 3443 3444 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT 3445 Set this parameter to enable fastmap automatically on images 3446 without a fastmap. 3447 default: 0 3448 3449 CONFIG_MTD_UBI_FM_DEBUG 3450 Enable UBI fastmap debug 3451 default: 0 3452 3453- UBIFS support 3454 CONFIG_CMD_UBIFS 3455 3456 Adds commands for interacting with UBI volumes formatted as 3457 UBIFS. UBIFS is read-only in u-boot. 3458 3459 Requires UBI support as well as CONFIG_LZO 3460 3461 CONFIG_UBIFS_SILENCE_MSG 3462 3463 Make the verbose messages from UBIFS stop printing. This leaves 3464 warnings and errors enabled. 3465 3466- SPL framework 3467 CONFIG_SPL 3468 Enable building of SPL globally. 3469 3470 CONFIG_SPL_LDSCRIPT 3471 LDSCRIPT for linking the SPL binary. 3472 3473 CONFIG_SPL_MAX_FOOTPRINT 3474 Maximum size in memory allocated to the SPL, BSS included. 3475 When defined, the linker checks that the actual memory 3476 used by SPL from _start to __bss_end does not exceed it. 3477 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE 3478 must not be both defined at the same time. 3479 3480 CONFIG_SPL_MAX_SIZE 3481 Maximum size of the SPL image (text, data, rodata, and 3482 linker lists sections), BSS excluded. 3483 When defined, the linker checks that the actual size does 3484 not exceed it. 3485 3486 CONFIG_SPL_TEXT_BASE 3487 TEXT_BASE for linking the SPL binary. 3488 3489 CONFIG_SPL_RELOC_TEXT_BASE 3490 Address to relocate to. If unspecified, this is equal to 3491 CONFIG_SPL_TEXT_BASE (i.e. no relocation is done). 3492 3493 CONFIG_SPL_BSS_START_ADDR 3494 Link address for the BSS within the SPL binary. 3495 3496 CONFIG_SPL_BSS_MAX_SIZE 3497 Maximum size in memory allocated to the SPL BSS. 3498 When defined, the linker checks that the actual memory used 3499 by SPL from __bss_start to __bss_end does not exceed it. 3500 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE 3501 must not be both defined at the same time. 3502 3503 CONFIG_SPL_STACK 3504 Adress of the start of the stack SPL will use 3505 3506 CONFIG_SPL_PANIC_ON_RAW_IMAGE 3507 When defined, SPL will panic() if the image it has 3508 loaded does not have a signature. 3509 Defining this is useful when code which loads images 3510 in SPL cannot guarantee that absolutely all read errors 3511 will be caught. 3512 An example is the LPC32XX MLC NAND driver, which will 3513 consider that a completely unreadable NAND block is bad, 3514 and thus should be skipped silently. 3515 3516 CONFIG_SPL_RELOC_STACK 3517 Adress of the start of the stack SPL will use after 3518 relocation. If unspecified, this is equal to 3519 CONFIG_SPL_STACK. 3520 3521 CONFIG_SYS_SPL_MALLOC_START 3522 Starting address of the malloc pool used in SPL. 3523 When this option is set the full malloc is used in SPL and 3524 it is set up by spl_init() and before that, the simple malloc() 3525 can be used if CONFIG_SYS_MALLOC_F is defined. 3526 3527 CONFIG_SYS_SPL_MALLOC_SIZE 3528 The size of the malloc pool used in SPL. 3529 3530 CONFIG_SPL_FRAMEWORK 3531 Enable the SPL framework under common/. This framework 3532 supports MMC, NAND and YMODEM loading of U-Boot and NAND 3533 NAND loading of the Linux Kernel. 3534 3535 CONFIG_SPL_OS_BOOT 3536 Enable booting directly to an OS from SPL. 3537 See also: doc/README.falcon 3538 3539 CONFIG_SPL_DISPLAY_PRINT 3540 For ARM, enable an optional function to print more information 3541 about the running system. 3542 3543 CONFIG_SPL_INIT_MINIMAL 3544 Arch init code should be built for a very small image 3545 3546 CONFIG_SPL_LIBCOMMON_SUPPORT 3547 Support for common/libcommon.o in SPL binary 3548 3549 CONFIG_SPL_LIBDISK_SUPPORT 3550 Support for disk/libdisk.o in SPL binary 3551 3552 CONFIG_SPL_I2C_SUPPORT 3553 Support for drivers/i2c/libi2c.o in SPL binary 3554 3555 CONFIG_SPL_GPIO_SUPPORT 3556 Support for drivers/gpio/libgpio.o in SPL binary 3557 3558 CONFIG_SPL_MMC_SUPPORT 3559 Support for drivers/mmc/libmmc.o in SPL binary 3560 3561 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR, 3562 CONFIG_SYS_U_BOOT_MAX_SIZE_SECTORS, 3563 Address and partition on the MMC to load U-Boot from 3564 when the MMC is being used in raw mode. 3565 3566 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_PARTITION 3567 Partition on the MMC to load U-Boot from when the MMC is being 3568 used in raw mode 3569 3570 CONFIG_SYS_MMCSD_RAW_MODE_KERNEL_SECTOR 3571 Sector to load kernel uImage from when MMC is being 3572 used in raw mode (for Falcon mode) 3573 3574 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTOR, 3575 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTORS 3576 Sector and number of sectors to load kernel argument 3577 parameters from when MMC is being used in raw mode 3578 (for falcon mode) 3579 3580 CONFIG_SYS_MMCSD_FS_BOOT_PARTITION 3581 Partition on the MMC to load U-Boot from when the MMC is being 3582 used in fs mode 3583 3584 CONFIG_SPL_FAT_SUPPORT 3585 Support for fs/fat/libfat.o in SPL binary 3586 3587 CONFIG_SPL_EXT_SUPPORT 3588 Support for EXT filesystem in SPL binary 3589 3590 CONFIG_SPL_FS_LOAD_PAYLOAD_NAME 3591 Filename to read to load U-Boot when reading from filesystem 3592 3593 CONFIG_SPL_FS_LOAD_KERNEL_NAME 3594 Filename to read to load kernel uImage when reading 3595 from filesystem (for Falcon mode) 3596 3597 CONFIG_SPL_FS_LOAD_ARGS_NAME 3598 Filename to read to load kernel argument parameters 3599 when reading from filesystem (for Falcon mode) 3600 3601 CONFIG_SPL_MPC83XX_WAIT_FOR_NAND 3602 Set this for NAND SPL on PPC mpc83xx targets, so that 3603 start.S waits for the rest of the SPL to load before 3604 continuing (the hardware starts execution after just 3605 loading the first page rather than the full 4K). 3606 3607 CONFIG_SPL_SKIP_RELOCATE 3608 Avoid SPL relocation 3609 3610 CONFIG_SPL_NAND_BASE 3611 Include nand_base.c in the SPL. Requires 3612 CONFIG_SPL_NAND_DRIVERS. 3613 3614 CONFIG_SPL_NAND_DRIVERS 3615 SPL uses normal NAND drivers, not minimal drivers. 3616 3617 CONFIG_SPL_NAND_ECC 3618 Include standard software ECC in the SPL 3619 3620 CONFIG_SPL_NAND_SIMPLE 3621 Support for NAND boot using simple NAND drivers that 3622 expose the cmd_ctrl() interface. 3623 3624 CONFIG_SPL_MTD_SUPPORT 3625 Support for the MTD subsystem within SPL. Useful for 3626 environment on NAND support within SPL. 3627 3628 CONFIG_SPL_NAND_RAW_ONLY 3629 Support to boot only raw u-boot.bin images. Use this only 3630 if you need to save space. 3631 3632 CONFIG_SPL_MPC8XXX_INIT_DDR_SUPPORT 3633 Set for the SPL on PPC mpc8xxx targets, support for 3634 drivers/ddr/fsl/libddr.o in SPL binary. 3635 3636 CONFIG_SPL_COMMON_INIT_DDR 3637 Set for common ddr init with serial presence detect in 3638 SPL binary. 3639 3640 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT, 3641 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE, 3642 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS, 3643 CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE, 3644 CONFIG_SYS_NAND_ECCBYTES 3645 Defines the size and behavior of the NAND that SPL uses 3646 to read U-Boot 3647 3648 CONFIG_SPL_NAND_BOOT 3649 Add support NAND boot 3650 3651 CONFIG_SYS_NAND_U_BOOT_OFFS 3652 Location in NAND to read U-Boot from 3653 3654 CONFIG_SYS_NAND_U_BOOT_DST 3655 Location in memory to load U-Boot to 3656 3657 CONFIG_SYS_NAND_U_BOOT_SIZE 3658 Size of image to load 3659 3660 CONFIG_SYS_NAND_U_BOOT_START 3661 Entry point in loaded image to jump to 3662 3663 CONFIG_SYS_NAND_HW_ECC_OOBFIRST 3664 Define this if you need to first read the OOB and then the 3665 data. This is used, for example, on davinci platforms. 3666 3667 CONFIG_SPL_OMAP3_ID_NAND 3668 Support for an OMAP3-specific set of functions to return the 3669 ID and MFR of the first attached NAND chip, if present. 3670 3671 CONFIG_SPL_SERIAL_SUPPORT 3672 Support for drivers/serial/libserial.o in SPL binary 3673 3674 CONFIG_SPL_SPI_FLASH_SUPPORT 3675 Support for drivers/mtd/spi/libspi_flash.o in SPL binary 3676 3677 CONFIG_SPL_SPI_SUPPORT 3678 Support for drivers/spi/libspi.o in SPL binary 3679 3680 CONFIG_SPL_RAM_DEVICE 3681 Support for running image already present in ram, in SPL binary 3682 3683 CONFIG_SPL_LIBGENERIC_SUPPORT 3684 Support for lib/libgeneric.o in SPL binary 3685 3686 CONFIG_SPL_ENV_SUPPORT 3687 Support for the environment operating in SPL binary 3688 3689 CONFIG_SPL_NET_SUPPORT 3690 Support for the net/libnet.o in SPL binary. 3691 It conflicts with SPL env from storage medium specified by 3692 CONFIG_ENV_IS_xxx but CONFIG_ENV_IS_NOWHERE 3693 3694 CONFIG_SPL_PAD_TO 3695 Image offset to which the SPL should be padded before appending 3696 the SPL payload. By default, this is defined as 3697 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined. 3698 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL 3699 payload without any padding, or >= CONFIG_SPL_MAX_SIZE. 3700 3701 CONFIG_SPL_TARGET 3702 Final target image containing SPL and payload. Some SPLs 3703 use an arch-specific makefile fragment instead, for 3704 example if more than one image needs to be produced. 3705 3706 CONFIG_FIT_SPL_PRINT 3707 Printing information about a FIT image adds quite a bit of 3708 code to SPL. So this is normally disabled in SPL. Use this 3709 option to re-enable it. This will affect the output of the 3710 bootm command when booting a FIT image. 3711 3712- TPL framework 3713 CONFIG_TPL 3714 Enable building of TPL globally. 3715 3716 CONFIG_TPL_PAD_TO 3717 Image offset to which the TPL should be padded before appending 3718 the TPL payload. By default, this is defined as 3719 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined. 3720 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL 3721 payload without any padding, or >= CONFIG_SPL_MAX_SIZE. 3722 3723Modem Support: 3724-------------- 3725 3726[so far only for SMDK2400 boards] 3727 3728- Modem support enable: 3729 CONFIG_MODEM_SUPPORT 3730 3731- RTS/CTS Flow control enable: 3732 CONFIG_HWFLOW 3733 3734- Interrupt support (PPC): 3735 3736 There are common interrupt_init() and timer_interrupt() 3737 for all PPC archs. interrupt_init() calls interrupt_init_cpu() 3738 for CPU specific initialization. interrupt_init_cpu() 3739 should set decrementer_count to appropriate value. If 3740 CPU resets decrementer automatically after interrupt 3741 (ppc4xx) it should set decrementer_count to zero. 3742 timer_interrupt() calls timer_interrupt_cpu() for CPU 3743 specific handling. If board has watchdog / status_led 3744 / other_activity_monitor it works automatically from 3745 general timer_interrupt(). 3746 3747- General: 3748 3749 In the target system modem support is enabled when a 3750 specific key (key combination) is pressed during 3751 power-on. Otherwise U-Boot will boot normally 3752 (autoboot). The key_pressed() function is called from 3753 board_init(). Currently key_pressed() is a dummy 3754 function, returning 1 and thus enabling modem 3755 initialization. 3756 3757 If there are no modem init strings in the 3758 environment, U-Boot proceed to autoboot; the 3759 previous output (banner, info printfs) will be 3760 suppressed, though. 3761 3762 See also: doc/README.Modem 3763 3764Board initialization settings: 3765------------------------------ 3766 3767During Initialization u-boot calls a number of board specific functions 3768to allow the preparation of board specific prerequisites, e.g. pin setup 3769before drivers are initialized. To enable these callbacks the 3770following configuration macros have to be defined. Currently this is 3771architecture specific, so please check arch/your_architecture/lib/board.c 3772typically in board_init_f() and board_init_r(). 3773 3774- CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f() 3775- CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r() 3776- CONFIG_BOARD_LATE_INIT: Call board_late_init() 3777- CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init() 3778 3779Configuration Settings: 3780----------------------- 3781 3782- CONFIG_SYS_SUPPORT_64BIT_DATA: Defined automatically if compiled as 64-bit. 3783 Optionally it can be defined to support 64-bit memory commands. 3784 3785- CONFIG_SYS_LONGHELP: Defined when you want long help messages included; 3786 undefine this when you're short of memory. 3787 3788- CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default 3789 width of the commands listed in the 'help' command output. 3790 3791- CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to 3792 prompt for user input. 3793 3794- CONFIG_SYS_CBSIZE: Buffer size for input from the Console 3795 3796- CONFIG_SYS_PBSIZE: Buffer size for Console output 3797 3798- CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands 3799 3800- CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to 3801 the application (usually a Linux kernel) when it is 3802 booted 3803 3804- CONFIG_SYS_BAUDRATE_TABLE: 3805 List of legal baudrate settings for this board. 3806 3807- CONFIG_SYS_CONSOLE_INFO_QUIET 3808 Suppress display of console information at boot. 3809 3810- CONFIG_SYS_CONSOLE_IS_IN_ENV 3811 If the board specific function 3812 extern int overwrite_console (void); 3813 returns 1, the stdin, stderr and stdout are switched to the 3814 serial port, else the settings in the environment are used. 3815 3816- CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE 3817 Enable the call to overwrite_console(). 3818 3819- CONFIG_SYS_CONSOLE_ENV_OVERWRITE 3820 Enable overwrite of previous console environment settings. 3821 3822- CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END: 3823 Begin and End addresses of the area used by the 3824 simple memory test. 3825 3826- CONFIG_SYS_ALT_MEMTEST: 3827 Enable an alternate, more extensive memory test. 3828 3829- CONFIG_SYS_MEMTEST_SCRATCH: 3830 Scratch address used by the alternate memory test 3831 You only need to set this if address zero isn't writeable 3832 3833- CONFIG_SYS_MEM_RESERVE_SECURE 3834 If defined, the size of CONFIG_SYS_MEM_RESERVE_SECURE memory 3835 is substracted from total RAM and won't be reported to OS. 3836 This memory can be used as secure memory. A variable 3837 gd->secure_ram is used to track the location. In systems 3838 the RAM base is not zero, or RAM is divided into banks, 3839 this variable needs to be recalcuated to get the address. 3840 3841- CONFIG_SYS_MEM_TOP_HIDE: 3842 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header, 3843 this specified memory area will get subtracted from the top 3844 (end) of RAM and won't get "touched" at all by U-Boot. By 3845 fixing up gd->ram_size the Linux kernel should gets passed 3846 the now "corrected" memory size and won't touch it either. 3847 This should work for arch/ppc and arch/powerpc. Only Linux 3848 board ports in arch/powerpc with bootwrapper support that 3849 recalculate the memory size from the SDRAM controller setup 3850 will have to get fixed in Linux additionally. 3851 3852 This option can be used as a workaround for the 440EPx/GRx 3853 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't 3854 be touched. 3855 3856 WARNING: Please make sure that this value is a multiple of 3857 the Linux page size (normally 4k). If this is not the case, 3858 then the end address of the Linux memory will be located at a 3859 non page size aligned address and this could cause major 3860 problems. 3861 3862- CONFIG_SYS_LOADS_BAUD_CHANGE: 3863 Enable temporary baudrate change while serial download 3864 3865- CONFIG_SYS_SDRAM_BASE: 3866 Physical start address of SDRAM. _Must_ be 0 here. 3867 3868- CONFIG_SYS_MBIO_BASE: 3869 Physical start address of Motherboard I/O (if using a 3870 Cogent motherboard) 3871 3872- CONFIG_SYS_FLASH_BASE: 3873 Physical start address of Flash memory. 3874 3875- CONFIG_SYS_MONITOR_BASE: 3876 Physical start address of boot monitor code (set by 3877 make config files to be same as the text base address 3878 (CONFIG_SYS_TEXT_BASE) used when linking) - same as 3879 CONFIG_SYS_FLASH_BASE when booting from flash. 3880 3881- CONFIG_SYS_MONITOR_LEN: 3882 Size of memory reserved for monitor code, used to 3883 determine _at_compile_time_ (!) if the environment is 3884 embedded within the U-Boot image, or in a separate 3885 flash sector. 3886 3887- CONFIG_SYS_MALLOC_LEN: 3888 Size of DRAM reserved for malloc() use. 3889 3890- CONFIG_SYS_MALLOC_F_LEN 3891 Size of the malloc() pool for use before relocation. If 3892 this is defined, then a very simple malloc() implementation 3893 will become available before relocation. The address is just 3894 below the global data, and the stack is moved down to make 3895 space. 3896 3897 This feature allocates regions with increasing addresses 3898 within the region. calloc() is supported, but realloc() 3899 is not available. free() is supported but does nothing. 3900 The memory will be freed (or in fact just forgotten) when 3901 U-Boot relocates itself. 3902 3903 Pre-relocation malloc() is only supported on ARM and sandbox 3904 at present but is fairly easy to enable for other archs. 3905 3906- CONFIG_SYS_MALLOC_SIMPLE 3907 Provides a simple and small malloc() and calloc() for those 3908 boards which do not use the full malloc in SPL (which is 3909 enabled with CONFIG_SYS_SPL_MALLOC_START). 3910 3911- CONFIG_SYS_NONCACHED_MEMORY: 3912 Size of non-cached memory area. This area of memory will be 3913 typically located right below the malloc() area and mapped 3914 uncached in the MMU. This is useful for drivers that would 3915 otherwise require a lot of explicit cache maintenance. For 3916 some drivers it's also impossible to properly maintain the 3917 cache. For example if the regions that need to be flushed 3918 are not a multiple of the cache-line size, *and* padding 3919 cannot be allocated between the regions to align them (i.e. 3920 if the HW requires a contiguous array of regions, and the 3921 size of each region is not cache-aligned), then a flush of 3922 one region may result in overwriting data that hardware has 3923 written to another region in the same cache-line. This can 3924 happen for example in network drivers where descriptors for 3925 buffers are typically smaller than the CPU cache-line (e.g. 3926 16 bytes vs. 32 or 64 bytes). 3927 3928 Non-cached memory is only supported on 32-bit ARM at present. 3929 3930- CONFIG_SYS_BOOTM_LEN: 3931 Normally compressed uImages are limited to an 3932 uncompressed size of 8 MBytes. If this is not enough, 3933 you can define CONFIG_SYS_BOOTM_LEN in your board config file 3934 to adjust this setting to your needs. 3935 3936- CONFIG_SYS_BOOTMAPSZ: 3937 Maximum size of memory mapped by the startup code of 3938 the Linux kernel; all data that must be processed by 3939 the Linux kernel (bd_info, boot arguments, FDT blob if 3940 used) must be put below this limit, unless "bootm_low" 3941 environment variable is defined and non-zero. In such case 3942 all data for the Linux kernel must be between "bootm_low" 3943 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment 3944 variable "bootm_mapsize" will override the value of 3945 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined, 3946 then the value in "bootm_size" will be used instead. 3947 3948- CONFIG_SYS_BOOT_RAMDISK_HIGH: 3949 Enable initrd_high functionality. If defined then the 3950 initrd_high feature is enabled and the bootm ramdisk subcommand 3951 is enabled. 3952 3953- CONFIG_SYS_BOOT_GET_CMDLINE: 3954 Enables allocating and saving kernel cmdline in space between 3955 "bootm_low" and "bootm_low" + BOOTMAPSZ. 3956 3957- CONFIG_SYS_BOOT_GET_KBD: 3958 Enables allocating and saving a kernel copy of the bd_info in 3959 space between "bootm_low" and "bootm_low" + BOOTMAPSZ. 3960 3961- CONFIG_SYS_MAX_FLASH_BANKS: 3962 Max number of Flash memory banks 3963 3964- CONFIG_SYS_MAX_FLASH_SECT: 3965 Max number of sectors on a Flash chip 3966 3967- CONFIG_SYS_FLASH_ERASE_TOUT: 3968 Timeout for Flash erase operations (in ms) 3969 3970- CONFIG_SYS_FLASH_WRITE_TOUT: 3971 Timeout for Flash write operations (in ms) 3972 3973- CONFIG_SYS_FLASH_LOCK_TOUT 3974 Timeout for Flash set sector lock bit operation (in ms) 3975 3976- CONFIG_SYS_FLASH_UNLOCK_TOUT 3977 Timeout for Flash clear lock bits operation (in ms) 3978 3979- CONFIG_SYS_FLASH_PROTECTION 3980 If defined, hardware flash sectors protection is used 3981 instead of U-Boot software protection. 3982 3983- CONFIG_SYS_DIRECT_FLASH_TFTP: 3984 3985 Enable TFTP transfers directly to flash memory; 3986 without this option such a download has to be 3987 performed in two steps: (1) download to RAM, and (2) 3988 copy from RAM to flash. 3989 3990 The two-step approach is usually more reliable, since 3991 you can check if the download worked before you erase 3992 the flash, but in some situations (when system RAM is 3993 too limited to allow for a temporary copy of the 3994 downloaded image) this option may be very useful. 3995 3996- CONFIG_SYS_FLASH_CFI: 3997 Define if the flash driver uses extra elements in the 3998 common flash structure for storing flash geometry. 3999 4000- CONFIG_FLASH_CFI_DRIVER 4001 This option also enables the building of the cfi_flash driver 4002 in the drivers directory 4003 4004- CONFIG_FLASH_CFI_MTD 4005 This option enables the building of the cfi_mtd driver 4006 in the drivers directory. The driver exports CFI flash 4007 to the MTD layer. 4008 4009- CONFIG_SYS_FLASH_USE_BUFFER_WRITE 4010 Use buffered writes to flash. 4011 4012- CONFIG_FLASH_SPANSION_S29WS_N 4013 s29ws-n MirrorBit flash has non-standard addresses for buffered 4014 write commands. 4015 4016- CONFIG_SYS_FLASH_QUIET_TEST 4017 If this option is defined, the common CFI flash doesn't 4018 print it's warning upon not recognized FLASH banks. This 4019 is useful, if some of the configured banks are only 4020 optionally available. 4021 4022- CONFIG_FLASH_SHOW_PROGRESS 4023 If defined (must be an integer), print out countdown 4024 digits and dots. Recommended value: 45 (9..1) for 80 4025 column displays, 15 (3..1) for 40 column displays. 4026 4027- CONFIG_FLASH_VERIFY 4028 If defined, the content of the flash (destination) is compared 4029 against the source after the write operation. An error message 4030 will be printed when the contents are not identical. 4031 Please note that this option is useless in nearly all cases, 4032 since such flash programming errors usually are detected earlier 4033 while unprotecting/erasing/programming. Please only enable 4034 this option if you really know what you are doing. 4035 4036- CONFIG_SYS_RX_ETH_BUFFER: 4037 Defines the number of Ethernet receive buffers. On some 4038 Ethernet controllers it is recommended to set this value 4039 to 8 or even higher (EEPRO100 or 405 EMAC), since all 4040 buffers can be full shortly after enabling the interface 4041 on high Ethernet traffic. 4042 Defaults to 4 if not defined. 4043 4044- CONFIG_ENV_MAX_ENTRIES 4045 4046 Maximum number of entries in the hash table that is used 4047 internally to store the environment settings. The default 4048 setting is supposed to be generous and should work in most 4049 cases. This setting can be used to tune behaviour; see 4050 lib/hashtable.c for details. 4051 4052- CONFIG_ENV_FLAGS_LIST_DEFAULT 4053- CONFIG_ENV_FLAGS_LIST_STATIC 4054 Enable validation of the values given to environment variables when 4055 calling env set. Variables can be restricted to only decimal, 4056 hexadecimal, or boolean. If CONFIG_CMD_NET is also defined, 4057 the variables can also be restricted to IP address or MAC address. 4058 4059 The format of the list is: 4060 type_attribute = [s|d|x|b|i|m] 4061 access_attribute = [a|r|o|c] 4062 attributes = type_attribute[access_attribute] 4063 entry = variable_name[:attributes] 4064 list = entry[,list] 4065 4066 The type attributes are: 4067 s - String (default) 4068 d - Decimal 4069 x - Hexadecimal 4070 b - Boolean ([1yYtT|0nNfF]) 4071 i - IP address 4072 m - MAC address 4073 4074 The access attributes are: 4075 a - Any (default) 4076 r - Read-only 4077 o - Write-once 4078 c - Change-default 4079 4080 - CONFIG_ENV_FLAGS_LIST_DEFAULT 4081 Define this to a list (string) to define the ".flags" 4082 environment variable in the default or embedded environment. 4083 4084 - CONFIG_ENV_FLAGS_LIST_STATIC 4085 Define this to a list (string) to define validation that 4086 should be done if an entry is not found in the ".flags" 4087 environment variable. To override a setting in the static 4088 list, simply add an entry for the same variable name to the 4089 ".flags" variable. 4090 4091 If CONFIG_REGEX is defined, the variable_name above is evaluated as a 4092 regular expression. This allows multiple variables to define the same 4093 flags without explicitly listing them for each variable. 4094 4095- CONFIG_ENV_ACCESS_IGNORE_FORCE 4096 If defined, don't allow the -f switch to env set override variable 4097 access flags. 4098 4099- CONFIG_SYS_GENERIC_BOARD 4100 This selects the architecture-generic board system instead of the 4101 architecture-specific board files. It is intended to move boards 4102 to this new framework over time. Defining this will disable the 4103 arch/foo/lib/board.c file and use common/board_f.c and 4104 common/board_r.c instead. To use this option your architecture 4105 must support it (i.e. must select HAVE_GENERIC_BOARD in arch/Kconfig). 4106 If you find problems enabling this option on your board please report 4107 the problem and send patches! 4108 4109- CONFIG_OMAP_PLATFORM_RESET_TIME_MAX_USEC (OMAP only) 4110 This is set by OMAP boards for the max time that reset should 4111 be asserted. See doc/README.omap-reset-time for details on how 4112 the value can be calculated on a given board. 4113 4114- CONFIG_USE_STDINT 4115 If stdint.h is available with your toolchain you can define this 4116 option to enable it. You can provide option 'USE_STDINT=1' when 4117 building U-Boot to enable this. 4118 4119The following definitions that deal with the placement and management 4120of environment data (variable area); in general, we support the 4121following configurations: 4122 4123- CONFIG_BUILD_ENVCRC: 4124 4125 Builds up envcrc with the target environment so that external utils 4126 may easily extract it and embed it in final U-Boot images. 4127 4128- CONFIG_ENV_IS_IN_FLASH: 4129 4130 Define this if the environment is in flash memory. 4131 4132 a) The environment occupies one whole flash sector, which is 4133 "embedded" in the text segment with the U-Boot code. This 4134 happens usually with "bottom boot sector" or "top boot 4135 sector" type flash chips, which have several smaller 4136 sectors at the start or the end. For instance, such a 4137 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In 4138 such a case you would place the environment in one of the 4139 4 kB sectors - with U-Boot code before and after it. With 4140 "top boot sector" type flash chips, you would put the 4141 environment in one of the last sectors, leaving a gap 4142 between U-Boot and the environment. 4143 4144 - CONFIG_ENV_OFFSET: 4145 4146 Offset of environment data (variable area) to the 4147 beginning of flash memory; for instance, with bottom boot 4148 type flash chips the second sector can be used: the offset 4149 for this sector is given here. 4150 4151 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE. 4152 4153 - CONFIG_ENV_ADDR: 4154 4155 This is just another way to specify the start address of 4156 the flash sector containing the environment (instead of 4157 CONFIG_ENV_OFFSET). 4158 4159 - CONFIG_ENV_SECT_SIZE: 4160 4161 Size of the sector containing the environment. 4162 4163 4164 b) Sometimes flash chips have few, equal sized, BIG sectors. 4165 In such a case you don't want to spend a whole sector for 4166 the environment. 4167 4168 - CONFIG_ENV_SIZE: 4169 4170 If you use this in combination with CONFIG_ENV_IS_IN_FLASH 4171 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part 4172 of this flash sector for the environment. This saves 4173 memory for the RAM copy of the environment. 4174 4175 It may also save flash memory if you decide to use this 4176 when your environment is "embedded" within U-Boot code, 4177 since then the remainder of the flash sector could be used 4178 for U-Boot code. It should be pointed out that this is 4179 STRONGLY DISCOURAGED from a robustness point of view: 4180 updating the environment in flash makes it always 4181 necessary to erase the WHOLE sector. If something goes 4182 wrong before the contents has been restored from a copy in 4183 RAM, your target system will be dead. 4184 4185 - CONFIG_ENV_ADDR_REDUND 4186 CONFIG_ENV_SIZE_REDUND 4187 4188 These settings describe a second storage area used to hold 4189 a redundant copy of the environment data, so that there is 4190 a valid backup copy in case there is a power failure during 4191 a "saveenv" operation. 4192 4193BE CAREFUL! Any changes to the flash layout, and some changes to the 4194source code will make it necessary to adapt <board>/u-boot.lds* 4195accordingly! 4196 4197 4198- CONFIG_ENV_IS_IN_NVRAM: 4199 4200 Define this if you have some non-volatile memory device 4201 (NVRAM, battery buffered SRAM) which you want to use for the 4202 environment. 4203 4204 - CONFIG_ENV_ADDR: 4205 - CONFIG_ENV_SIZE: 4206 4207 These two #defines are used to determine the memory area you 4208 want to use for environment. It is assumed that this memory 4209 can just be read and written to, without any special 4210 provision. 4211 4212BE CAREFUL! The first access to the environment happens quite early 4213in U-Boot initialization (when we try to get the setting of for the 4214console baudrate). You *MUST* have mapped your NVRAM area then, or 4215U-Boot will hang. 4216 4217Please note that even with NVRAM we still use a copy of the 4218environment in RAM: we could work on NVRAM directly, but we want to 4219keep settings there always unmodified except somebody uses "saveenv" 4220to save the current settings. 4221 4222 4223- CONFIG_ENV_IS_IN_EEPROM: 4224 4225 Use this if you have an EEPROM or similar serial access 4226 device and a driver for it. 4227 4228 - CONFIG_ENV_OFFSET: 4229 - CONFIG_ENV_SIZE: 4230 4231 These two #defines specify the offset and size of the 4232 environment area within the total memory of your EEPROM. 4233 4234 - CONFIG_SYS_I2C_EEPROM_ADDR: 4235 If defined, specified the chip address of the EEPROM device. 4236 The default address is zero. 4237 4238 - CONFIG_SYS_I2C_EEPROM_BUS: 4239 If defined, specified the i2c bus of the EEPROM device. 4240 4241 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS: 4242 If defined, the number of bits used to address bytes in a 4243 single page in the EEPROM device. A 64 byte page, for example 4244 would require six bits. 4245 4246 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS: 4247 If defined, the number of milliseconds to delay between 4248 page writes. The default is zero milliseconds. 4249 4250 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN: 4251 The length in bytes of the EEPROM memory array address. Note 4252 that this is NOT the chip address length! 4253 4254 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW: 4255 EEPROM chips that implement "address overflow" are ones 4256 like Catalyst 24WC04/08/16 which has 9/10/11 bits of 4257 address and the extra bits end up in the "chip address" bit 4258 slots. This makes a 24WC08 (1Kbyte) chip look like four 256 4259 byte chips. 4260 4261 Note that we consider the length of the address field to 4262 still be one byte because the extra address bits are hidden 4263 in the chip address. 4264 4265 - CONFIG_SYS_EEPROM_SIZE: 4266 The size in bytes of the EEPROM device. 4267 4268 - CONFIG_ENV_EEPROM_IS_ON_I2C 4269 define this, if you have I2C and SPI activated, and your 4270 EEPROM, which holds the environment, is on the I2C bus. 4271 4272 - CONFIG_I2C_ENV_EEPROM_BUS 4273 if you have an Environment on an EEPROM reached over 4274 I2C muxes, you can define here, how to reach this 4275 EEPROM. For example: 4276 4277 #define CONFIG_I2C_ENV_EEPROM_BUS 1 4278 4279 EEPROM which holds the environment, is reached over 4280 a pca9547 i2c mux with address 0x70, channel 3. 4281 4282- CONFIG_ENV_IS_IN_DATAFLASH: 4283 4284 Define this if you have a DataFlash memory device which you 4285 want to use for the environment. 4286 4287 - CONFIG_ENV_OFFSET: 4288 - CONFIG_ENV_ADDR: 4289 - CONFIG_ENV_SIZE: 4290 4291 These three #defines specify the offset and size of the 4292 environment area within the total memory of your DataFlash placed 4293 at the specified address. 4294 4295- CONFIG_ENV_IS_IN_SPI_FLASH: 4296 4297 Define this if you have a SPI Flash memory device which you 4298 want to use for the environment. 4299 4300 - CONFIG_ENV_OFFSET: 4301 - CONFIG_ENV_SIZE: 4302 4303 These two #defines specify the offset and size of the 4304 environment area within the SPI Flash. CONFIG_ENV_OFFSET must be 4305 aligned to an erase sector boundary. 4306 4307 - CONFIG_ENV_SECT_SIZE: 4308 4309 Define the SPI flash's sector size. 4310 4311 - CONFIG_ENV_OFFSET_REDUND (optional): 4312 4313 This setting describes a second storage area of CONFIG_ENV_SIZE 4314 size used to hold a redundant copy of the environment data, so 4315 that there is a valid backup copy in case there is a power failure 4316 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be 4317 aligned to an erase sector boundary. 4318 4319 - CONFIG_ENV_SPI_BUS (optional): 4320 - CONFIG_ENV_SPI_CS (optional): 4321 4322 Define the SPI bus and chip select. If not defined they will be 0. 4323 4324 - CONFIG_ENV_SPI_MAX_HZ (optional): 4325 4326 Define the SPI max work clock. If not defined then use 1MHz. 4327 4328 - CONFIG_ENV_SPI_MODE (optional): 4329 4330 Define the SPI work mode. If not defined then use SPI_MODE_3. 4331 4332- CONFIG_ENV_IS_IN_REMOTE: 4333 4334 Define this if you have a remote memory space which you 4335 want to use for the local device's environment. 4336 4337 - CONFIG_ENV_ADDR: 4338 - CONFIG_ENV_SIZE: 4339 4340 These two #defines specify the address and size of the 4341 environment area within the remote memory space. The 4342 local device can get the environment from remote memory 4343 space by SRIO or PCIE links. 4344 4345BE CAREFUL! For some special cases, the local device can not use 4346"saveenv" command. For example, the local device will get the 4347environment stored in a remote NOR flash by SRIO or PCIE link, 4348but it can not erase, write this NOR flash by SRIO or PCIE interface. 4349 4350- CONFIG_ENV_IS_IN_NAND: 4351 4352 Define this if you have a NAND device which you want to use 4353 for the environment. 4354 4355 - CONFIG_ENV_OFFSET: 4356 - CONFIG_ENV_SIZE: 4357 4358 These two #defines specify the offset and size of the environment 4359 area within the first NAND device. CONFIG_ENV_OFFSET must be 4360 aligned to an erase block boundary. 4361 4362 - CONFIG_ENV_OFFSET_REDUND (optional): 4363 4364 This setting describes a second storage area of CONFIG_ENV_SIZE 4365 size used to hold a redundant copy of the environment data, so 4366 that there is a valid backup copy in case there is a power failure 4367 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be 4368 aligned to an erase block boundary. 4369 4370 - CONFIG_ENV_RANGE (optional): 4371 4372 Specifies the length of the region in which the environment 4373 can be written. This should be a multiple of the NAND device's 4374 block size. Specifying a range with more erase blocks than 4375 are needed to hold CONFIG_ENV_SIZE allows bad blocks within 4376 the range to be avoided. 4377 4378 - CONFIG_ENV_OFFSET_OOB (optional): 4379 4380 Enables support for dynamically retrieving the offset of the 4381 environment from block zero's out-of-band data. The 4382 "nand env.oob" command can be used to record this offset. 4383 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when 4384 using CONFIG_ENV_OFFSET_OOB. 4385 4386- CONFIG_NAND_ENV_DST 4387 4388 Defines address in RAM to which the nand_spl code should copy the 4389 environment. If redundant environment is used, it will be copied to 4390 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE. 4391 4392- CONFIG_ENV_IS_IN_UBI: 4393 4394 Define this if you have an UBI volume that you want to use for the 4395 environment. This has the benefit of wear-leveling the environment 4396 accesses, which is important on NAND. 4397 4398 - CONFIG_ENV_UBI_PART: 4399 4400 Define this to a string that is the mtd partition containing the UBI. 4401 4402 - CONFIG_ENV_UBI_VOLUME: 4403 4404 Define this to the name of the volume that you want to store the 4405 environment in. 4406 4407 - CONFIG_ENV_UBI_VOLUME_REDUND: 4408 4409 Define this to the name of another volume to store a second copy of 4410 the environment in. This will enable redundant environments in UBI. 4411 It is assumed that both volumes are in the same MTD partition. 4412 4413 - CONFIG_UBI_SILENCE_MSG 4414 - CONFIG_UBIFS_SILENCE_MSG 4415 4416 You will probably want to define these to avoid a really noisy system 4417 when storing the env in UBI. 4418 4419- CONFIG_ENV_IS_IN_FAT: 4420 Define this if you want to use the FAT file system for the environment. 4421 4422 - FAT_ENV_INTERFACE: 4423 4424 Define this to a string that is the name of the block device. 4425 4426 - FAT_ENV_DEV_AND_PART: 4427 4428 Define this to a string to specify the partition of the device. It can 4429 be as following: 4430 4431 "D:P", "D:0", "D", "D:" or "D:auto" (D, P are integers. And P >= 1) 4432 - "D:P": device D partition P. Error occurs if device D has no 4433 partition table. 4434 - "D:0": device D. 4435 - "D" or "D:": device D partition 1 if device D has partition 4436 table, or the whole device D if has no partition 4437 table. 4438 - "D:auto": first partition in device D with bootable flag set. 4439 If none, first valid partition in device D. If no 4440 partition table then means device D. 4441 4442 - FAT_ENV_FILE: 4443 4444 It's a string of the FAT file name. This file use to store the 4445 environment. 4446 4447 - CONFIG_FAT_WRITE: 4448 This should be defined. Otherwise it cannot save the environment file. 4449 4450- CONFIG_ENV_IS_IN_MMC: 4451 4452 Define this if you have an MMC device which you want to use for the 4453 environment. 4454 4455 - CONFIG_SYS_MMC_ENV_DEV: 4456 4457 Specifies which MMC device the environment is stored in. 4458 4459 - CONFIG_SYS_MMC_ENV_PART (optional): 4460 4461 Specifies which MMC partition the environment is stored in. If not 4462 set, defaults to partition 0, the user area. Common values might be 4463 1 (first MMC boot partition), 2 (second MMC boot partition). 4464 4465 - CONFIG_ENV_OFFSET: 4466 - CONFIG_ENV_SIZE: 4467 4468 These two #defines specify the offset and size of the environment 4469 area within the specified MMC device. 4470 4471 If offset is positive (the usual case), it is treated as relative to 4472 the start of the MMC partition. If offset is negative, it is treated 4473 as relative to the end of the MMC partition. This can be useful if 4474 your board may be fitted with different MMC devices, which have 4475 different sizes for the MMC partitions, and you always want the 4476 environment placed at the very end of the partition, to leave the 4477 maximum possible space before it, to store other data. 4478 4479 These two values are in units of bytes, but must be aligned to an 4480 MMC sector boundary. 4481 4482 - CONFIG_ENV_OFFSET_REDUND (optional): 4483 4484 Specifies a second storage area, of CONFIG_ENV_SIZE size, used to 4485 hold a redundant copy of the environment data. This provides a 4486 valid backup copy in case the other copy is corrupted, e.g. due 4487 to a power failure during a "saveenv" operation. 4488 4489 This value may also be positive or negative; this is handled in the 4490 same way as CONFIG_ENV_OFFSET. 4491 4492 This value is also in units of bytes, but must also be aligned to 4493 an MMC sector boundary. 4494 4495 - CONFIG_ENV_SIZE_REDUND (optional): 4496 4497 This value need not be set, even when CONFIG_ENV_OFFSET_REDUND is 4498 set. If this value is set, it must be set to the same value as 4499 CONFIG_ENV_SIZE. 4500 4501- CONFIG_SYS_SPI_INIT_OFFSET 4502 4503 Defines offset to the initial SPI buffer area in DPRAM. The 4504 area is used at an early stage (ROM part) if the environment 4505 is configured to reside in the SPI EEPROM: We need a 520 byte 4506 scratch DPRAM area. It is used between the two initialization 4507 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems 4508 to be a good choice since it makes it far enough from the 4509 start of the data area as well as from the stack pointer. 4510 4511Please note that the environment is read-only until the monitor 4512has been relocated to RAM and a RAM copy of the environment has been 4513created; also, when using EEPROM you will have to use getenv_f() 4514until then to read environment variables. 4515 4516The environment is protected by a CRC32 checksum. Before the monitor 4517is relocated into RAM, as a result of a bad CRC you will be working 4518with the compiled-in default environment - *silently*!!! [This is 4519necessary, because the first environment variable we need is the 4520"baudrate" setting for the console - if we have a bad CRC, we don't 4521have any device yet where we could complain.] 4522 4523Note: once the monitor has been relocated, then it will complain if 4524the default environment is used; a new CRC is computed as soon as you 4525use the "saveenv" command to store a valid environment. 4526 4527- CONFIG_SYS_FAULT_ECHO_LINK_DOWN: 4528 Echo the inverted Ethernet link state to the fault LED. 4529 4530 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR 4531 also needs to be defined. 4532 4533- CONFIG_SYS_FAULT_MII_ADDR: 4534 MII address of the PHY to check for the Ethernet link state. 4535 4536- CONFIG_NS16550_MIN_FUNCTIONS: 4537 Define this if you desire to only have use of the NS16550_init 4538 and NS16550_putc functions for the serial driver located at 4539 drivers/serial/ns16550.c. This option is useful for saving 4540 space for already greatly restricted images, including but not 4541 limited to NAND_SPL configurations. 4542 4543- CONFIG_DISPLAY_BOARDINFO 4544 Display information about the board that U-Boot is running on 4545 when U-Boot starts up. The board function checkboard() is called 4546 to do this. 4547 4548- CONFIG_DISPLAY_BOARDINFO_LATE 4549 Similar to the previous option, but display this information 4550 later, once stdio is running and output goes to the LCD, if 4551 present. 4552 4553- CONFIG_BOARD_SIZE_LIMIT: 4554 Maximum size of the U-Boot image. When defined, the 4555 build system checks that the actual size does not 4556 exceed it. 4557 4558Low Level (hardware related) configuration options: 4559--------------------------------------------------- 4560 4561- CONFIG_SYS_CACHELINE_SIZE: 4562 Cache Line Size of the CPU. 4563 4564- CONFIG_SYS_DEFAULT_IMMR: 4565 Default address of the IMMR after system reset. 4566 4567 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU, 4568 and RPXsuper) to be able to adjust the position of 4569 the IMMR register after a reset. 4570 4571- CONFIG_SYS_CCSRBAR_DEFAULT: 4572 Default (power-on reset) physical address of CCSR on Freescale 4573 PowerPC SOCs. 4574 4575- CONFIG_SYS_CCSRBAR: 4576 Virtual address of CCSR. On a 32-bit build, this is typically 4577 the same value as CONFIG_SYS_CCSRBAR_DEFAULT. 4578 4579 CONFIG_SYS_DEFAULT_IMMR must also be set to this value, 4580 for cross-platform code that uses that macro instead. 4581 4582- CONFIG_SYS_CCSRBAR_PHYS: 4583 Physical address of CCSR. CCSR can be relocated to a new 4584 physical address, if desired. In this case, this macro should 4585 be set to that address. Otherwise, it should be set to the 4586 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR 4587 is typically relocated on 36-bit builds. It is recommended 4588 that this macro be defined via the _HIGH and _LOW macros: 4589 4590 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH 4591 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW) 4592 4593- CONFIG_SYS_CCSRBAR_PHYS_HIGH: 4594 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically 4595 either 0 (32-bit build) or 0xF (36-bit build). This macro is 4596 used in assembly code, so it must not contain typecasts or 4597 integer size suffixes (e.g. "ULL"). 4598 4599- CONFIG_SYS_CCSRBAR_PHYS_LOW: 4600 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is 4601 used in assembly code, so it must not contain typecasts or 4602 integer size suffixes (e.g. "ULL"). 4603 4604- CONFIG_SYS_CCSR_DO_NOT_RELOCATE: 4605 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be 4606 forced to a value that ensures that CCSR is not relocated. 4607 4608- Floppy Disk Support: 4609 CONFIG_SYS_FDC_DRIVE_NUMBER 4610 4611 the default drive number (default value 0) 4612 4613 CONFIG_SYS_ISA_IO_STRIDE 4614 4615 defines the spacing between FDC chipset registers 4616 (default value 1) 4617 4618 CONFIG_SYS_ISA_IO_OFFSET 4619 4620 defines the offset of register from address. It 4621 depends on which part of the data bus is connected to 4622 the FDC chipset. (default value 0) 4623 4624 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and 4625 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their 4626 default value. 4627 4628 if CONFIG_SYS_FDC_HW_INIT is defined, then the function 4629 fdc_hw_init() is called at the beginning of the FDC 4630 setup. fdc_hw_init() must be provided by the board 4631 source code. It is used to make hardware-dependent 4632 initializations. 4633 4634- CONFIG_IDE_AHB: 4635 Most IDE controllers were designed to be connected with PCI 4636 interface. Only few of them were designed for AHB interface. 4637 When software is doing ATA command and data transfer to 4638 IDE devices through IDE-AHB controller, some additional 4639 registers accessing to these kind of IDE-AHB controller 4640 is required. 4641 4642- CONFIG_SYS_IMMR: Physical address of the Internal Memory. 4643 DO NOT CHANGE unless you know exactly what you're 4644 doing! (11-4) [MPC8xx/82xx systems only] 4645 4646- CONFIG_SYS_INIT_RAM_ADDR: 4647 4648 Start address of memory area that can be used for 4649 initial data and stack; please note that this must be 4650 writable memory that is working WITHOUT special 4651 initialization, i. e. you CANNOT use normal RAM which 4652 will become available only after programming the 4653 memory controller and running certain initialization 4654 sequences. 4655 4656 U-Boot uses the following memory types: 4657 - MPC8xx and MPC8260: IMMR (internal memory of the CPU) 4658 - MPC824X: data cache 4659 - PPC4xx: data cache 4660 4661- CONFIG_SYS_GBL_DATA_OFFSET: 4662 4663 Offset of the initial data structure in the memory 4664 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually 4665 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial 4666 data is located at the end of the available space 4667 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE - 4668 CONFIG_SYS_INIT_DATA_SIZE), and the initial stack is just 4669 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR + 4670 CONFIG_SYS_GBL_DATA_OFFSET) downward. 4671 4672 Note: 4673 On the MPC824X (or other systems that use the data 4674 cache for initial memory) the address chosen for 4675 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must 4676 point to an otherwise UNUSED address space between 4677 the top of RAM and the start of the PCI space. 4678 4679- CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6) 4680 4681- CONFIG_SYS_SYPCR: System Protection Control (11-9) 4682 4683- CONFIG_SYS_TBSCR: Time Base Status and Control (11-26) 4684 4685- CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31) 4686 4687- CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30) 4688 4689- CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27) 4690 4691- CONFIG_SYS_OR_TIMING_SDRAM: 4692 SDRAM timing 4693 4694- CONFIG_SYS_MAMR_PTA: 4695 periodic timer for refresh 4696 4697- CONFIG_SYS_DER: Debug Event Register (37-47) 4698 4699- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM, 4700 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP, 4701 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM, 4702 CONFIG_SYS_BR1_PRELIM: 4703 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH) 4704 4705- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE, 4706 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM, 4707 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM: 4708 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM) 4709 4710- CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K, 4711 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL: 4712 Machine Mode Register and Memory Periodic Timer 4713 Prescaler definitions (SDRAM timing) 4714 4715- CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]: 4716 enable I2C microcode relocation patch (MPC8xx); 4717 define relocation offset in DPRAM [DSP2] 4718 4719- CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]: 4720 enable SMC microcode relocation patch (MPC8xx); 4721 define relocation offset in DPRAM [SMC1] 4722 4723- CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]: 4724 enable SPI microcode relocation patch (MPC8xx); 4725 define relocation offset in DPRAM [SCC4] 4726 4727- CONFIG_SYS_USE_OSCCLK: 4728 Use OSCM clock mode on MBX8xx board. Be careful, 4729 wrong setting might damage your board. Read 4730 doc/README.MBX before setting this variable! 4731 4732- CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only) 4733 Offset of the bootmode word in DPRAM used by post 4734 (Power On Self Tests). This definition overrides 4735 #define'd default value in commproc.h resp. 4736 cpm_8260.h. 4737 4738- CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB, 4739 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL, 4740 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS, 4741 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB, 4742 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START, 4743 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL, 4744 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE, 4745 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only) 4746 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set. 4747 4748- CONFIG_PCI_DISABLE_PCIE: 4749 Disable PCI-Express on systems where it is supported but not 4750 required. 4751 4752- CONFIG_PCI_ENUM_ONLY 4753 Only scan through and get the devices on the buses. 4754 Don't do any setup work, presumably because someone or 4755 something has already done it, and we don't need to do it 4756 a second time. Useful for platforms that are pre-booted 4757 by coreboot or similar. 4758 4759- CONFIG_PCI_INDIRECT_BRIDGE: 4760 Enable support for indirect PCI bridges. 4761 4762- CONFIG_SYS_SRIO: 4763 Chip has SRIO or not 4764 4765- CONFIG_SRIO1: 4766 Board has SRIO 1 port available 4767 4768- CONFIG_SRIO2: 4769 Board has SRIO 2 port available 4770 4771- CONFIG_SRIO_PCIE_BOOT_MASTER 4772 Board can support master function for Boot from SRIO and PCIE 4773 4774- CONFIG_SYS_SRIOn_MEM_VIRT: 4775 Virtual Address of SRIO port 'n' memory region 4776 4777- CONFIG_SYS_SRIOn_MEM_PHYS: 4778 Physical Address of SRIO port 'n' memory region 4779 4780- CONFIG_SYS_SRIOn_MEM_SIZE: 4781 Size of SRIO port 'n' memory region 4782 4783- CONFIG_SYS_NAND_BUSWIDTH_16BIT 4784 Defined to tell the NAND controller that the NAND chip is using 4785 a 16 bit bus. 4786 Not all NAND drivers use this symbol. 4787 Example of drivers that use it: 4788 - drivers/mtd/nand/ndfc.c 4789 - drivers/mtd/nand/mxc_nand.c 4790 4791- CONFIG_SYS_NDFC_EBC0_CFG 4792 Sets the EBC0_CFG register for the NDFC. If not defined 4793 a default value will be used. 4794 4795- CONFIG_SPD_EEPROM 4796 Get DDR timing information from an I2C EEPROM. Common 4797 with pluggable memory modules such as SODIMMs 4798 4799 SPD_EEPROM_ADDRESS 4800 I2C address of the SPD EEPROM 4801 4802- CONFIG_SYS_SPD_BUS_NUM 4803 If SPD EEPROM is on an I2C bus other than the first 4804 one, specify here. Note that the value must resolve 4805 to something your driver can deal with. 4806 4807- CONFIG_SYS_DDR_RAW_TIMING 4808 Get DDR timing information from other than SPD. Common with 4809 soldered DDR chips onboard without SPD. DDR raw timing 4810 parameters are extracted from datasheet and hard-coded into 4811 header files or board specific files. 4812 4813- CONFIG_FSL_DDR_INTERACTIVE 4814 Enable interactive DDR debugging. See doc/README.fsl-ddr. 4815 4816- CONFIG_FSL_DDR_SYNC_REFRESH 4817 Enable sync of refresh for multiple controllers. 4818 4819- CONFIG_FSL_DDR_BIST 4820 Enable built-in memory test for Freescale DDR controllers. 4821 4822- CONFIG_SYS_83XX_DDR_USES_CS0 4823 Only for 83xx systems. If specified, then DDR should 4824 be configured using CS0 and CS1 instead of CS2 and CS3. 4825 4826- CONFIG_ETHER_ON_FEC[12] 4827 Define to enable FEC[12] on a 8xx series processor. 4828 4829- CONFIG_FEC[12]_PHY 4830 Define to the hardcoded PHY address which corresponds 4831 to the given FEC; i. e. 4832 #define CONFIG_FEC1_PHY 4 4833 means that the PHY with address 4 is connected to FEC1 4834 4835 When set to -1, means to probe for first available. 4836 4837- CONFIG_FEC[12]_PHY_NORXERR 4838 The PHY does not have a RXERR line (RMII only). 4839 (so program the FEC to ignore it). 4840 4841- CONFIG_RMII 4842 Enable RMII mode for all FECs. 4843 Note that this is a global option, we can't 4844 have one FEC in standard MII mode and another in RMII mode. 4845 4846- CONFIG_CRC32_VERIFY 4847 Add a verify option to the crc32 command. 4848 The syntax is: 4849 4850 => crc32 -v <address> <count> <crc32> 4851 4852 Where address/count indicate a memory area 4853 and crc32 is the correct crc32 which the 4854 area should have. 4855 4856- CONFIG_LOOPW 4857 Add the "loopw" memory command. This only takes effect if 4858 the memory commands are activated globally (CONFIG_CMD_MEM). 4859 4860- CONFIG_MX_CYCLIC 4861 Add the "mdc" and "mwc" memory commands. These are cyclic 4862 "md/mw" commands. 4863 Examples: 4864 4865 => mdc.b 10 4 500 4866 This command will print 4 bytes (10,11,12,13) each 500 ms. 4867 4868 => mwc.l 100 12345678 10 4869 This command will write 12345678 to address 100 all 10 ms. 4870 4871 This only takes effect if the memory commands are activated 4872 globally (CONFIG_CMD_MEM). 4873 4874- CONFIG_SKIP_LOWLEVEL_INIT 4875 [ARM, NDS32, MIPS only] If this variable is defined, then certain 4876 low level initializations (like setting up the memory 4877 controller) are omitted and/or U-Boot does not 4878 relocate itself into RAM. 4879 4880 Normally this variable MUST NOT be defined. The only 4881 exception is when U-Boot is loaded (to RAM) by some 4882 other boot loader or by a debugger which performs 4883 these initializations itself. 4884 4885- CONFIG_SPL_BUILD 4886 Modifies the behaviour of start.S when compiling a loader 4887 that is executed before the actual U-Boot. E.g. when 4888 compiling a NAND SPL. 4889 4890- CONFIG_TPL_BUILD 4891 Modifies the behaviour of start.S when compiling a loader 4892 that is executed after the SPL and before the actual U-Boot. 4893 It is loaded by the SPL. 4894 4895- CONFIG_SYS_MPC85XX_NO_RESETVEC 4896 Only for 85xx systems. If this variable is specified, the section 4897 .resetvec is not kept and the section .bootpg is placed in the 4898 previous 4k of the .text section. 4899 4900- CONFIG_ARCH_MAP_SYSMEM 4901 Generally U-Boot (and in particular the md command) uses 4902 effective address. It is therefore not necessary to regard 4903 U-Boot address as virtual addresses that need to be translated 4904 to physical addresses. However, sandbox requires this, since 4905 it maintains its own little RAM buffer which contains all 4906 addressable memory. This option causes some memory accesses 4907 to be mapped through map_sysmem() / unmap_sysmem(). 4908 4909- CONFIG_USE_ARCH_MEMCPY 4910 CONFIG_USE_ARCH_MEMSET 4911 If these options are used a optimized version of memcpy/memset will 4912 be used if available. These functions may be faster under some 4913 conditions but may increase the binary size. 4914 4915- CONFIG_X86_RESET_VECTOR 4916 If defined, the x86 reset vector code is included. This is not 4917 needed when U-Boot is running from Coreboot. 4918 4919- CONFIG_SYS_MPUCLK 4920 Defines the MPU clock speed (in MHz). 4921 4922 NOTE : currently only supported on AM335x platforms. 4923 4924- CONFIG_SPL_AM33XX_ENABLE_RTC32K_OSC: 4925 Enables the RTC32K OSC on AM33xx based plattforms 4926 4927- CONFIG_SYS_NAND_NO_SUBPAGE_WRITE 4928 Option to disable subpage write in NAND driver 4929 driver that uses this: 4930 drivers/mtd/nand/davinci_nand.c 4931 4932Freescale QE/FMAN Firmware Support: 4933----------------------------------- 4934 4935The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the 4936loading of "firmware", which is encoded in the QE firmware binary format. 4937This firmware often needs to be loaded during U-Boot booting, so macros 4938are used to identify the storage device (NOR flash, SPI, etc) and the address 4939within that device. 4940 4941- CONFIG_SYS_FMAN_FW_ADDR 4942 The address in the storage device where the FMAN microcode is located. The 4943 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro 4944 is also specified. 4945 4946- CONFIG_SYS_QE_FW_ADDR 4947 The address in the storage device where the QE microcode is located. The 4948 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro 4949 is also specified. 4950 4951- CONFIG_SYS_QE_FMAN_FW_LENGTH 4952 The maximum possible size of the firmware. The firmware binary format 4953 has a field that specifies the actual size of the firmware, but it 4954 might not be possible to read any part of the firmware unless some 4955 local storage is allocated to hold the entire firmware first. 4956 4957- CONFIG_SYS_QE_FMAN_FW_IN_NOR 4958 Specifies that QE/FMAN firmware is located in NOR flash, mapped as 4959 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the 4960 virtual address in NOR flash. 4961 4962- CONFIG_SYS_QE_FMAN_FW_IN_NAND 4963 Specifies that QE/FMAN firmware is located in NAND flash. 4964 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash. 4965 4966- CONFIG_SYS_QE_FMAN_FW_IN_MMC 4967 Specifies that QE/FMAN firmware is located on the primary SD/MMC 4968 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device. 4969 4970- CONFIG_SYS_QE_FMAN_FW_IN_SPIFLASH 4971 Specifies that QE/FMAN firmware is located on the primary SPI 4972 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device. 4973 4974- CONFIG_SYS_QE_FMAN_FW_IN_REMOTE 4975 Specifies that QE/FMAN firmware is located in the remote (master) 4976 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which 4977 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound 4978 window->master inbound window->master LAW->the ucode address in 4979 master's memory space. 4980 4981Freescale Layerscape Management Complex Firmware Support: 4982--------------------------------------------------------- 4983The Freescale Layerscape Management Complex (MC) supports the loading of 4984"firmware". 4985This firmware often needs to be loaded during U-Boot booting, so macros 4986are used to identify the storage device (NOR flash, SPI, etc) and the address 4987within that device. 4988 4989- CONFIG_FSL_MC_ENET 4990 Enable the MC driver for Layerscape SoCs. 4991 4992- CONFIG_SYS_LS_MC_FW_ADDR 4993 The address in the storage device where the firmware is located. The 4994 meaning of this address depends on which CONFIG_SYS_LS_MC_FW_IN_xxx macro 4995 is also specified. 4996 4997- CONFIG_SYS_LS_MC_FW_LENGTH 4998 The maximum possible size of the firmware. The firmware binary format 4999 has a field that specifies the actual size of the firmware, but it 5000 might not be possible to read any part of the firmware unless some 5001 local storage is allocated to hold the entire firmware first. 5002 5003- CONFIG_SYS_LS_MC_FW_IN_NOR 5004 Specifies that MC firmware is located in NOR flash, mapped as 5005 normal addressable memory via the LBC. CONFIG_SYS_LS_MC_FW_ADDR is the 5006 virtual address in NOR flash. 5007 5008Freescale Layerscape Debug Server Support: 5009------------------------------------------- 5010The Freescale Layerscape Debug Server Support supports the loading of 5011"Debug Server firmware" and triggering SP boot-rom. 5012This firmware often needs to be loaded during U-Boot booting. 5013 5014- CONFIG_FSL_DEBUG_SERVER 5015 Enable the Debug Server for Layerscape SoCs. 5016 5017- CONFIG_SYS_DEBUG_SERVER_DRAM_BLOCK_MIN_SIZE 5018 Define minimum DDR size required for debug server image 5019 5020- CONFIG_SYS_MC_RSV_MEM_ALIGN 5021 Define alignment of reserved memory MC requires 5022 5023Reproducible builds 5024------------------- 5025 5026In order to achieve reproducible builds, timestamps used in the U-Boot build 5027process have to be set to a fixed value. 5028 5029This is done using the SOURCE_DATE_EPOCH environment variable. 5030SOURCE_DATE_EPOCH is to be set on the build host's shell, not as a configuration 5031option for U-Boot or an environment variable in U-Boot. 5032 5033SOURCE_DATE_EPOCH should be set to a number of seconds since the epoch, in UTC. 5034 5035Building the Software: 5036====================== 5037 5038Building U-Boot has been tested in several native build environments 5039and in many different cross environments. Of course we cannot support 5040all possibly existing versions of cross development tools in all 5041(potentially obsolete) versions. In case of tool chain problems we 5042recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK) 5043which is extensively used to build and test U-Boot. 5044 5045If you are not using a native environment, it is assumed that you 5046have GNU cross compiling tools available in your path. In this case, 5047you must set the environment variable CROSS_COMPILE in your shell. 5048Note that no changes to the Makefile or any other source files are 5049necessary. For example using the ELDK on a 4xx CPU, please enter: 5050 5051 $ CROSS_COMPILE=ppc_4xx- 5052 $ export CROSS_COMPILE 5053 5054Note: If you wish to generate Windows versions of the utilities in 5055 the tools directory you can use the MinGW toolchain 5056 (http://www.mingw.org). Set your HOST tools to the MinGW 5057 toolchain and execute 'make tools'. For example: 5058 5059 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools 5060 5061 Binaries such as tools/mkimage.exe will be created which can 5062 be executed on computers running Windows. 5063 5064U-Boot is intended to be simple to build. After installing the 5065sources you must configure U-Boot for one specific board type. This 5066is done by typing: 5067 5068 make NAME_defconfig 5069 5070where "NAME_defconfig" is the name of one of the existing configu- 5071rations; see boards.cfg for supported names. 5072 5073Note: for some board special configuration names may exist; check if 5074 additional information is available from the board vendor; for 5075 instance, the TQM823L systems are available without (standard) 5076 or with LCD support. You can select such additional "features" 5077 when choosing the configuration, i. e. 5078 5079 make TQM823L_defconfig 5080 - will configure for a plain TQM823L, i. e. no LCD support 5081 5082 make TQM823L_LCD_defconfig 5083 - will configure for a TQM823L with U-Boot console on LCD 5084 5085 etc. 5086 5087 5088Finally, type "make all", and you should get some working U-Boot 5089images ready for download to / installation on your system: 5090 5091- "u-boot.bin" is a raw binary image 5092- "u-boot" is an image in ELF binary format 5093- "u-boot.srec" is in Motorola S-Record format 5094 5095By default the build is performed locally and the objects are saved 5096in the source directory. One of the two methods can be used to change 5097this behavior and build U-Boot to some external directory: 5098 50991. Add O= to the make command line invocations: 5100 5101 make O=/tmp/build distclean 5102 make O=/tmp/build NAME_defconfig 5103 make O=/tmp/build all 5104 51052. Set environment variable KBUILD_OUTPUT to point to the desired location: 5106 5107 export KBUILD_OUTPUT=/tmp/build 5108 make distclean 5109 make NAME_defconfig 5110 make all 5111 5112Note that the command line "O=" setting overrides the KBUILD_OUTPUT environment 5113variable. 5114 5115 5116Please be aware that the Makefiles assume you are using GNU make, so 5117for instance on NetBSD you might need to use "gmake" instead of 5118native "make". 5119 5120 5121If the system board that you have is not listed, then you will need 5122to port U-Boot to your hardware platform. To do this, follow these 5123steps: 5124 51251. Create a new directory to hold your board specific code. Add any 5126 files you need. In your board directory, you will need at least 5127 the "Makefile" and a "<board>.c". 51282. Create a new configuration file "include/configs/<board>.h" for 5129 your board. 51303. If you're porting U-Boot to a new CPU, then also create a new 5131 directory to hold your CPU specific code. Add any files you need. 51324. Run "make <board>_defconfig" with your new name. 51335. Type "make", and you should get a working "u-boot.srec" file 5134 to be installed on your target system. 51356. Debug and solve any problems that might arise. 5136 [Of course, this last step is much harder than it sounds.] 5137 5138 5139Testing of U-Boot Modifications, Ports to New Hardware, etc.: 5140============================================================== 5141 5142If you have modified U-Boot sources (for instance added a new board 5143or support for new devices, a new CPU, etc.) you are expected to 5144provide feedback to the other developers. The feedback normally takes 5145the form of a "patch", i. e. a context diff against a certain (latest 5146official or latest in the git repository) version of U-Boot sources. 5147 5148But before you submit such a patch, please verify that your modifi- 5149cation did not break existing code. At least make sure that *ALL* of 5150the supported boards compile WITHOUT ANY compiler warnings. To do so, 5151just run the "MAKEALL" script, which will configure and build U-Boot 5152for ALL supported system. Be warned, this will take a while. You can 5153select which (cross) compiler to use by passing a `CROSS_COMPILE' 5154environment variable to the script, i. e. to use the ELDK cross tools 5155you can type 5156 5157 CROSS_COMPILE=ppc_8xx- MAKEALL 5158 5159or to build on a native PowerPC system you can type 5160 5161 CROSS_COMPILE=' ' MAKEALL 5162 5163When using the MAKEALL script, the default behaviour is to build 5164U-Boot in the source directory. This location can be changed by 5165setting the BUILD_DIR environment variable. Also, for each target 5166built, the MAKEALL script saves two log files (<target>.ERR and 5167<target>.MAKEALL) in the <source dir>/LOG directory. This default 5168location can be changed by setting the MAKEALL_LOGDIR environment 5169variable. For example: 5170 5171 export BUILD_DIR=/tmp/build 5172 export MAKEALL_LOGDIR=/tmp/log 5173 CROSS_COMPILE=ppc_8xx- MAKEALL 5174 5175With the above settings build objects are saved in the /tmp/build, 5176log files are saved in the /tmp/log and the source tree remains clean 5177during the whole build process. 5178 5179 5180See also "U-Boot Porting Guide" below. 5181 5182 5183Monitor Commands - Overview: 5184============================ 5185 5186go - start application at address 'addr' 5187run - run commands in an environment variable 5188bootm - boot application image from memory 5189bootp - boot image via network using BootP/TFTP protocol 5190bootz - boot zImage from memory 5191tftpboot- boot image via network using TFTP protocol 5192 and env variables "ipaddr" and "serverip" 5193 (and eventually "gatewayip") 5194tftpput - upload a file via network using TFTP protocol 5195rarpboot- boot image via network using RARP/TFTP protocol 5196diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd' 5197loads - load S-Record file over serial line 5198loadb - load binary file over serial line (kermit mode) 5199md - memory display 5200mm - memory modify (auto-incrementing) 5201nm - memory modify (constant address) 5202mw - memory write (fill) 5203cp - memory copy 5204cmp - memory compare 5205crc32 - checksum calculation 5206i2c - I2C sub-system 5207sspi - SPI utility commands 5208base - print or set address offset 5209printenv- print environment variables 5210setenv - set environment variables 5211saveenv - save environment variables to persistent storage 5212protect - enable or disable FLASH write protection 5213erase - erase FLASH memory 5214flinfo - print FLASH memory information 5215nand - NAND memory operations (see doc/README.nand) 5216bdinfo - print Board Info structure 5217iminfo - print header information for application image 5218coninfo - print console devices and informations 5219ide - IDE sub-system 5220loop - infinite loop on address range 5221loopw - infinite write loop on address range 5222mtest - simple RAM test 5223icache - enable or disable instruction cache 5224dcache - enable or disable data cache 5225reset - Perform RESET of the CPU 5226echo - echo args to console 5227version - print monitor version 5228help - print online help 5229? - alias for 'help' 5230 5231 5232Monitor Commands - Detailed Description: 5233======================================== 5234 5235TODO. 5236 5237For now: just type "help <command>". 5238 5239 5240Environment Variables: 5241====================== 5242 5243U-Boot supports user configuration using Environment Variables which 5244can be made persistent by saving to Flash memory. 5245 5246Environment Variables are set using "setenv", printed using 5247"printenv", and saved to Flash using "saveenv". Using "setenv" 5248without a value can be used to delete a variable from the 5249environment. As long as you don't save the environment you are 5250working with an in-memory copy. In case the Flash area containing the 5251environment is erased by accident, a default environment is provided. 5252 5253Some configuration options can be set using Environment Variables. 5254 5255List of environment variables (most likely not complete): 5256 5257 baudrate - see CONFIG_BAUDRATE 5258 5259 bootdelay - see CONFIG_BOOTDELAY 5260 5261 bootcmd - see CONFIG_BOOTCOMMAND 5262 5263 bootargs - Boot arguments when booting an RTOS image 5264 5265 bootfile - Name of the image to load with TFTP 5266 5267 bootm_low - Memory range available for image processing in the bootm 5268 command can be restricted. This variable is given as 5269 a hexadecimal number and defines lowest address allowed 5270 for use by the bootm command. See also "bootm_size" 5271 environment variable. Address defined by "bootm_low" is 5272 also the base of the initial memory mapping for the Linux 5273 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and 5274 bootm_mapsize. 5275 5276 bootm_mapsize - Size of the initial memory mapping for the Linux kernel. 5277 This variable is given as a hexadecimal number and it 5278 defines the size of the memory region starting at base 5279 address bootm_low that is accessible by the Linux kernel 5280 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used 5281 as the default value if it is defined, and bootm_size is 5282 used otherwise. 5283 5284 bootm_size - Memory range available for image processing in the bootm 5285 command can be restricted. This variable is given as 5286 a hexadecimal number and defines the size of the region 5287 allowed for use by the bootm command. See also "bootm_low" 5288 environment variable. 5289 5290 updatefile - Location of the software update file on a TFTP server, used 5291 by the automatic software update feature. Please refer to 5292 documentation in doc/README.update for more details. 5293 5294 autoload - if set to "no" (any string beginning with 'n'), 5295 "bootp" will just load perform a lookup of the 5296 configuration from the BOOTP server, but not try to 5297 load any image using TFTP 5298 5299 autostart - if set to "yes", an image loaded using the "bootp", 5300 "rarpboot", "tftpboot" or "diskboot" commands will 5301 be automatically started (by internally calling 5302 "bootm") 5303 5304 If set to "no", a standalone image passed to the 5305 "bootm" command will be copied to the load address 5306 (and eventually uncompressed), but NOT be started. 5307 This can be used to load and uncompress arbitrary 5308 data. 5309 5310 fdt_high - if set this restricts the maximum address that the 5311 flattened device tree will be copied into upon boot. 5312 For example, if you have a system with 1 GB memory 5313 at physical address 0x10000000, while Linux kernel 5314 only recognizes the first 704 MB as low memory, you 5315 may need to set fdt_high as 0x3C000000 to have the 5316 device tree blob be copied to the maximum address 5317 of the 704 MB low memory, so that Linux kernel can 5318 access it during the boot procedure. 5319 5320 If this is set to the special value 0xFFFFFFFF then 5321 the fdt will not be copied at all on boot. For this 5322 to work it must reside in writable memory, have 5323 sufficient padding on the end of it for u-boot to 5324 add the information it needs into it, and the memory 5325 must be accessible by the kernel. 5326 5327 fdtcontroladdr- if set this is the address of the control flattened 5328 device tree used by U-Boot when CONFIG_OF_CONTROL is 5329 defined. 5330 5331 i2cfast - (PPC405GP|PPC405EP only) 5332 if set to 'y' configures Linux I2C driver for fast 5333 mode (400kHZ). This environment variable is used in 5334 initialization code. So, for changes to be effective 5335 it must be saved and board must be reset. 5336 5337 initrd_high - restrict positioning of initrd images: 5338 If this variable is not set, initrd images will be 5339 copied to the highest possible address in RAM; this 5340 is usually what you want since it allows for 5341 maximum initrd size. If for some reason you want to 5342 make sure that the initrd image is loaded below the 5343 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment 5344 variable to a value of "no" or "off" or "0". 5345 Alternatively, you can set it to a maximum upper 5346 address to use (U-Boot will still check that it 5347 does not overwrite the U-Boot stack and data). 5348 5349 For instance, when you have a system with 16 MB 5350 RAM, and want to reserve 4 MB from use by Linux, 5351 you can do this by adding "mem=12M" to the value of 5352 the "bootargs" variable. However, now you must make 5353 sure that the initrd image is placed in the first 5354 12 MB as well - this can be done with 5355 5356 setenv initrd_high 00c00000 5357 5358 If you set initrd_high to 0xFFFFFFFF, this is an 5359 indication to U-Boot that all addresses are legal 5360 for the Linux kernel, including addresses in flash 5361 memory. In this case U-Boot will NOT COPY the 5362 ramdisk at all. This may be useful to reduce the 5363 boot time on your system, but requires that this 5364 feature is supported by your Linux kernel. 5365 5366 ipaddr - IP address; needed for tftpboot command 5367 5368 loadaddr - Default load address for commands like "bootp", 5369 "rarpboot", "tftpboot", "loadb" or "diskboot" 5370 5371 loads_echo - see CONFIG_LOADS_ECHO 5372 5373 serverip - TFTP server IP address; needed for tftpboot command 5374 5375 bootretry - see CONFIG_BOOT_RETRY_TIME 5376 5377 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR 5378 5379 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR 5380 5381 ethprime - controls which interface is used first. 5382 5383 ethact - controls which interface is currently active. 5384 For example you can do the following 5385 5386 => setenv ethact FEC 5387 => ping 192.168.0.1 # traffic sent on FEC 5388 => setenv ethact SCC 5389 => ping 10.0.0.1 # traffic sent on SCC 5390 5391 ethrotate - When set to "no" U-Boot does not go through all 5392 available network interfaces. 5393 It just stays at the currently selected interface. 5394 5395 netretry - When set to "no" each network operation will 5396 either succeed or fail without retrying. 5397 When set to "once" the network operation will 5398 fail when all the available network interfaces 5399 are tried once without success. 5400 Useful on scripts which control the retry operation 5401 themselves. 5402 5403 npe_ucode - set load address for the NPE microcode 5404 5405 silent_linux - If set then Linux will be told to boot silently, by 5406 changing the console to be empty. If "yes" it will be 5407 made silent. If "no" it will not be made silent. If 5408 unset, then it will be made silent if the U-Boot console 5409 is silent. 5410 5411 tftpsrcp - If this is set, the value is used for TFTP's 5412 UDP source port. 5413 5414 tftpdstp - If this is set, the value is used for TFTP's UDP 5415 destination port instead of the Well Know Port 69. 5416 5417 tftpblocksize - Block size to use for TFTP transfers; if not set, 5418 we use the TFTP server's default block size 5419 5420 tftptimeout - Retransmission timeout for TFTP packets (in milli- 5421 seconds, minimum value is 1000 = 1 second). Defines 5422 when a packet is considered to be lost so it has to 5423 be retransmitted. The default is 5000 = 5 seconds. 5424 Lowering this value may make downloads succeed 5425 faster in networks with high packet loss rates or 5426 with unreliable TFTP servers. 5427 5428 tftptimeoutcountmax - maximum count of TFTP timeouts (no 5429 unit, minimum value = 0). Defines how many timeouts 5430 can happen during a single file transfer before that 5431 transfer is aborted. The default is 10, and 0 means 5432 'no timeouts allowed'. Increasing this value may help 5433 downloads succeed with high packet loss rates, or with 5434 unreliable TFTP servers or client hardware. 5435 5436 vlan - When set to a value < 4095 the traffic over 5437 Ethernet is encapsulated/received over 802.1q 5438 VLAN tagged frames. 5439 5440The following image location variables contain the location of images 5441used in booting. The "Image" column gives the role of the image and is 5442not an environment variable name. The other columns are environment 5443variable names. "File Name" gives the name of the file on a TFTP 5444server, "RAM Address" gives the location in RAM the image will be 5445loaded to, and "Flash Location" gives the image's address in NOR 5446flash or offset in NAND flash. 5447 5448*Note* - these variables don't have to be defined for all boards, some 5449boards currently use other variables for these purposes, and some 5450boards use these variables for other purposes. 5451 5452Image File Name RAM Address Flash Location 5453----- --------- ----------- -------------- 5454u-boot u-boot u-boot_addr_r u-boot_addr 5455Linux kernel bootfile kernel_addr_r kernel_addr 5456device tree blob fdtfile fdt_addr_r fdt_addr 5457ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr 5458 5459The following environment variables may be used and automatically 5460updated by the network boot commands ("bootp" and "rarpboot"), 5461depending the information provided by your boot server: 5462 5463 bootfile - see above 5464 dnsip - IP address of your Domain Name Server 5465 dnsip2 - IP address of your secondary Domain Name Server 5466 gatewayip - IP address of the Gateway (Router) to use 5467 hostname - Target hostname 5468 ipaddr - see above 5469 netmask - Subnet Mask 5470 rootpath - Pathname of the root filesystem on the NFS server 5471 serverip - see above 5472 5473 5474There are two special Environment Variables: 5475 5476 serial# - contains hardware identification information such 5477 as type string and/or serial number 5478 ethaddr - Ethernet address 5479 5480These variables can be set only once (usually during manufacturing of 5481the board). U-Boot refuses to delete or overwrite these variables 5482once they have been set once. 5483 5484 5485Further special Environment Variables: 5486 5487 ver - Contains the U-Boot version string as printed 5488 with the "version" command. This variable is 5489 readonly (see CONFIG_VERSION_VARIABLE). 5490 5491 5492Please note that changes to some configuration parameters may take 5493only effect after the next boot (yes, that's just like Windoze :-). 5494 5495 5496Callback functions for environment variables: 5497--------------------------------------------- 5498 5499For some environment variables, the behavior of u-boot needs to change 5500when their values are changed. This functionality allows functions to 5501be associated with arbitrary variables. On creation, overwrite, or 5502deletion, the callback will provide the opportunity for some side 5503effect to happen or for the change to be rejected. 5504 5505The callbacks are named and associated with a function using the 5506U_BOOT_ENV_CALLBACK macro in your board or driver code. 5507 5508These callbacks are associated with variables in one of two ways. The 5509static list can be added to by defining CONFIG_ENV_CALLBACK_LIST_STATIC 5510in the board configuration to a string that defines a list of 5511associations. The list must be in the following format: 5512 5513 entry = variable_name[:callback_name] 5514 list = entry[,list] 5515 5516If the callback name is not specified, then the callback is deleted. 5517Spaces are also allowed anywhere in the list. 5518 5519Callbacks can also be associated by defining the ".callbacks" variable 5520with the same list format above. Any association in ".callbacks" will 5521override any association in the static list. You can define 5522CONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the 5523".callbacks" environment variable in the default or embedded environment. 5524 5525If CONFIG_REGEX is defined, the variable_name above is evaluated as a 5526regular expression. This allows multiple variables to be connected to 5527the same callback without explicitly listing them all out. 5528 5529 5530Command Line Parsing: 5531===================== 5532 5533There are two different command line parsers available with U-Boot: 5534the old "simple" one, and the much more powerful "hush" shell: 5535 5536Old, simple command line parser: 5537-------------------------------- 5538 5539- supports environment variables (through setenv / saveenv commands) 5540- several commands on one line, separated by ';' 5541- variable substitution using "... ${name} ..." syntax 5542- special characters ('$', ';') can be escaped by prefixing with '\', 5543 for example: 5544 setenv bootcmd bootm \${address} 5545- You can also escape text by enclosing in single apostrophes, for example: 5546 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off' 5547 5548Hush shell: 5549----------- 5550 5551- similar to Bourne shell, with control structures like 5552 if...then...else...fi, for...do...done; while...do...done, 5553 until...do...done, ... 5554- supports environment ("global") variables (through setenv / saveenv 5555 commands) and local shell variables (through standard shell syntax 5556 "name=value"); only environment variables can be used with "run" 5557 command 5558 5559General rules: 5560-------------- 5561 5562(1) If a command line (or an environment variable executed by a "run" 5563 command) contains several commands separated by semicolon, and 5564 one of these commands fails, then the remaining commands will be 5565 executed anyway. 5566 5567(2) If you execute several variables with one call to run (i. e. 5568 calling run with a list of variables as arguments), any failing 5569 command will cause "run" to terminate, i. e. the remaining 5570 variables are not executed. 5571 5572Note for Redundant Ethernet Interfaces: 5573======================================= 5574 5575Some boards come with redundant Ethernet interfaces; U-Boot supports 5576such configurations and is capable of automatic selection of a 5577"working" interface when needed. MAC assignment works as follows: 5578 5579Network interfaces are numbered eth0, eth1, eth2, ... Corresponding 5580MAC addresses can be stored in the environment as "ethaddr" (=>eth0), 5581"eth1addr" (=>eth1), "eth2addr", ... 5582 5583If the network interface stores some valid MAC address (for instance 5584in SROM), this is used as default address if there is NO correspon- 5585ding setting in the environment; if the corresponding environment 5586variable is set, this overrides the settings in the card; that means: 5587 5588o If the SROM has a valid MAC address, and there is no address in the 5589 environment, the SROM's address is used. 5590 5591o If there is no valid address in the SROM, and a definition in the 5592 environment exists, then the value from the environment variable is 5593 used. 5594 5595o If both the SROM and the environment contain a MAC address, and 5596 both addresses are the same, this MAC address is used. 5597 5598o If both the SROM and the environment contain a MAC address, and the 5599 addresses differ, the value from the environment is used and a 5600 warning is printed. 5601 5602o If neither SROM nor the environment contain a MAC address, an error 5603 is raised. If CONFIG_NET_RANDOM_ETHADDR is defined, then in this case 5604 a random, locally-assigned MAC is used. 5605 5606If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses 5607will be programmed into hardware as part of the initialization process. This 5608may be skipped by setting the appropriate 'ethmacskip' environment variable. 5609The naming convention is as follows: 5610"ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc. 5611 5612Image Formats: 5613============== 5614 5615U-Boot is capable of booting (and performing other auxiliary operations on) 5616images in two formats: 5617 5618New uImage format (FIT) 5619----------------------- 5620 5621Flexible and powerful format based on Flattened Image Tree -- FIT (similar 5622to Flattened Device Tree). It allows the use of images with multiple 5623components (several kernels, ramdisks, etc.), with contents protected by 5624SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory. 5625 5626 5627Old uImage format 5628----------------- 5629 5630Old image format is based on binary files which can be basically anything, 5631preceded by a special header; see the definitions in include/image.h for 5632details; basically, the header defines the following image properties: 5633 5634* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD, 5635 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks, 5636 LynxOS, pSOS, QNX, RTEMS, INTEGRITY; 5637 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS, 5638 INTEGRITY). 5639* Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86, 5640 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit; 5641 Currently supported: ARM, AVR32, Intel x86, MIPS, NDS32, Nios II, PowerPC). 5642* Compression Type (uncompressed, gzip, bzip2) 5643* Load Address 5644* Entry Point 5645* Image Name 5646* Image Timestamp 5647 5648The header is marked by a special Magic Number, and both the header 5649and the data portions of the image are secured against corruption by 5650CRC32 checksums. 5651 5652 5653Linux Support: 5654============== 5655 5656Although U-Boot should support any OS or standalone application 5657easily, the main focus has always been on Linux during the design of 5658U-Boot. 5659 5660U-Boot includes many features that so far have been part of some 5661special "boot loader" code within the Linux kernel. Also, any 5662"initrd" images to be used are no longer part of one big Linux image; 5663instead, kernel and "initrd" are separate images. This implementation 5664serves several purposes: 5665 5666- the same features can be used for other OS or standalone 5667 applications (for instance: using compressed images to reduce the 5668 Flash memory footprint) 5669 5670- it becomes much easier to port new Linux kernel versions because 5671 lots of low-level, hardware dependent stuff are done by U-Boot 5672 5673- the same Linux kernel image can now be used with different "initrd" 5674 images; of course this also means that different kernel images can 5675 be run with the same "initrd". This makes testing easier (you don't 5676 have to build a new "zImage.initrd" Linux image when you just 5677 change a file in your "initrd"). Also, a field-upgrade of the 5678 software is easier now. 5679 5680 5681Linux HOWTO: 5682============ 5683 5684Porting Linux to U-Boot based systems: 5685--------------------------------------- 5686 5687U-Boot cannot save you from doing all the necessary modifications to 5688configure the Linux device drivers for use with your target hardware 5689(no, we don't intend to provide a full virtual machine interface to 5690Linux :-). 5691 5692But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot). 5693 5694Just make sure your machine specific header file (for instance 5695include/asm-ppc/tqm8xx.h) includes the same definition of the Board 5696Information structure as we define in include/asm-<arch>/u-boot.h, 5697and make sure that your definition of IMAP_ADDR uses the same value 5698as your U-Boot configuration in CONFIG_SYS_IMMR. 5699 5700Note that U-Boot now has a driver model, a unified model for drivers. 5701If you are adding a new driver, plumb it into driver model. If there 5702is no uclass available, you are encouraged to create one. See 5703doc/driver-model. 5704 5705 5706Configuring the Linux kernel: 5707----------------------------- 5708 5709No specific requirements for U-Boot. Make sure you have some root 5710device (initial ramdisk, NFS) for your target system. 5711 5712 5713Building a Linux Image: 5714----------------------- 5715 5716With U-Boot, "normal" build targets like "zImage" or "bzImage" are 5717not used. If you use recent kernel source, a new build target 5718"uImage" will exist which automatically builds an image usable by 5719U-Boot. Most older kernels also have support for a "pImage" target, 5720which was introduced for our predecessor project PPCBoot and uses a 5721100% compatible format. 5722 5723Example: 5724 5725 make TQM850L_defconfig 5726 make oldconfig 5727 make dep 5728 make uImage 5729 5730The "uImage" build target uses a special tool (in 'tools/mkimage') to 5731encapsulate a compressed Linux kernel image with header information, 5732CRC32 checksum etc. for use with U-Boot. This is what we are doing: 5733 5734* build a standard "vmlinux" kernel image (in ELF binary format): 5735 5736* convert the kernel into a raw binary image: 5737 5738 ${CROSS_COMPILE}-objcopy -O binary \ 5739 -R .note -R .comment \ 5740 -S vmlinux linux.bin 5741 5742* compress the binary image: 5743 5744 gzip -9 linux.bin 5745 5746* package compressed binary image for U-Boot: 5747 5748 mkimage -A ppc -O linux -T kernel -C gzip \ 5749 -a 0 -e 0 -n "Linux Kernel Image" \ 5750 -d linux.bin.gz uImage 5751 5752 5753The "mkimage" tool can also be used to create ramdisk images for use 5754with U-Boot, either separated from the Linux kernel image, or 5755combined into one file. "mkimage" encapsulates the images with a 64 5756byte header containing information about target architecture, 5757operating system, image type, compression method, entry points, time 5758stamp, CRC32 checksums, etc. 5759 5760"mkimage" can be called in two ways: to verify existing images and 5761print the header information, or to build new images. 5762 5763In the first form (with "-l" option) mkimage lists the information 5764contained in the header of an existing U-Boot image; this includes 5765checksum verification: 5766 5767 tools/mkimage -l image 5768 -l ==> list image header information 5769 5770The second form (with "-d" option) is used to build a U-Boot image 5771from a "data file" which is used as image payload: 5772 5773 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \ 5774 -n name -d data_file image 5775 -A ==> set architecture to 'arch' 5776 -O ==> set operating system to 'os' 5777 -T ==> set image type to 'type' 5778 -C ==> set compression type 'comp' 5779 -a ==> set load address to 'addr' (hex) 5780 -e ==> set entry point to 'ep' (hex) 5781 -n ==> set image name to 'name' 5782 -d ==> use image data from 'datafile' 5783 5784Right now, all Linux kernels for PowerPC systems use the same load 5785address (0x00000000), but the entry point address depends on the 5786kernel version: 5787 5788- 2.2.x kernels have the entry point at 0x0000000C, 5789- 2.3.x and later kernels have the entry point at 0x00000000. 5790 5791So a typical call to build a U-Boot image would read: 5792 5793 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 5794 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \ 5795 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \ 5796 > examples/uImage.TQM850L 5797 Image Name: 2.4.4 kernel for TQM850L 5798 Created: Wed Jul 19 02:34:59 2000 5799 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5800 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 5801 Load Address: 0x00000000 5802 Entry Point: 0x00000000 5803 5804To verify the contents of the image (or check for corruption): 5805 5806 -> tools/mkimage -l examples/uImage.TQM850L 5807 Image Name: 2.4.4 kernel for TQM850L 5808 Created: Wed Jul 19 02:34:59 2000 5809 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5810 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 5811 Load Address: 0x00000000 5812 Entry Point: 0x00000000 5813 5814NOTE: for embedded systems where boot time is critical you can trade 5815speed for memory and install an UNCOMPRESSED image instead: this 5816needs more space in Flash, but boots much faster since it does not 5817need to be uncompressed: 5818 5819 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz 5820 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 5821 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \ 5822 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \ 5823 > examples/uImage.TQM850L-uncompressed 5824 Image Name: 2.4.4 kernel for TQM850L 5825 Created: Wed Jul 19 02:34:59 2000 5826 Image Type: PowerPC Linux Kernel Image (uncompressed) 5827 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB 5828 Load Address: 0x00000000 5829 Entry Point: 0x00000000 5830 5831 5832Similar you can build U-Boot images from a 'ramdisk.image.gz' file 5833when your kernel is intended to use an initial ramdisk: 5834 5835 -> tools/mkimage -n 'Simple Ramdisk Image' \ 5836 > -A ppc -O linux -T ramdisk -C gzip \ 5837 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd 5838 Image Name: Simple Ramdisk Image 5839 Created: Wed Jan 12 14:01:50 2000 5840 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 5841 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB 5842 Load Address: 0x00000000 5843 Entry Point: 0x00000000 5844 5845The "dumpimage" is a tool to disassemble images built by mkimage. Its "-i" 5846option performs the converse operation of the mkimage's second form (the "-d" 5847option). Given an image built by mkimage, the dumpimage extracts a "data file" 5848from the image: 5849 5850 tools/dumpimage -i image -T type -p position data_file 5851 -i ==> extract from the 'image' a specific 'data_file' 5852 -T ==> set image type to 'type' 5853 -p ==> 'position' (starting at 0) of the 'data_file' inside the 'image' 5854 5855 5856Installing a Linux Image: 5857------------------------- 5858 5859To downloading a U-Boot image over the serial (console) interface, 5860you must convert the image to S-Record format: 5861 5862 objcopy -I binary -O srec examples/image examples/image.srec 5863 5864The 'objcopy' does not understand the information in the U-Boot 5865image header, so the resulting S-Record file will be relative to 5866address 0x00000000. To load it to a given address, you need to 5867specify the target address as 'offset' parameter with the 'loads' 5868command. 5869 5870Example: install the image to address 0x40100000 (which on the 5871TQM8xxL is in the first Flash bank): 5872 5873 => erase 40100000 401FFFFF 5874 5875 .......... done 5876 Erased 8 sectors 5877 5878 => loads 40100000 5879 ## Ready for S-Record download ... 5880 ~>examples/image.srec 5881 1 2 3 4 5 6 7 8 9 10 11 12 13 ... 5882 ... 5883 15989 15990 15991 15992 5884 [file transfer complete] 5885 [connected] 5886 ## Start Addr = 0x00000000 5887 5888 5889You can check the success of the download using the 'iminfo' command; 5890this includes a checksum verification so you can be sure no data 5891corruption happened: 5892 5893 => imi 40100000 5894 5895 ## Checking Image at 40100000 ... 5896 Image Name: 2.2.13 for initrd on TQM850L 5897 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5898 Data Size: 335725 Bytes = 327 kB = 0 MB 5899 Load Address: 00000000 5900 Entry Point: 0000000c 5901 Verifying Checksum ... OK 5902 5903 5904Boot Linux: 5905----------- 5906 5907The "bootm" command is used to boot an application that is stored in 5908memory (RAM or Flash). In case of a Linux kernel image, the contents 5909of the "bootargs" environment variable is passed to the kernel as 5910parameters. You can check and modify this variable using the 5911"printenv" and "setenv" commands: 5912 5913 5914 => printenv bootargs 5915 bootargs=root=/dev/ram 5916 5917 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5918 5919 => printenv bootargs 5920 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5921 5922 => bootm 40020000 5923 ## Booting Linux kernel at 40020000 ... 5924 Image Name: 2.2.13 for NFS on TQM850L 5925 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5926 Data Size: 381681 Bytes = 372 kB = 0 MB 5927 Load Address: 00000000 5928 Entry Point: 0000000c 5929 Verifying Checksum ... OK 5930 Uncompressing Kernel Image ... OK 5931 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 5932 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5933 time_init: decrementer frequency = 187500000/60 5934 Calibrating delay loop... 49.77 BogoMIPS 5935 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000] 5936 ... 5937 5938If you want to boot a Linux kernel with initial RAM disk, you pass 5939the memory addresses of both the kernel and the initrd image (PPBCOOT 5940format!) to the "bootm" command: 5941 5942 => imi 40100000 40200000 5943 5944 ## Checking Image at 40100000 ... 5945 Image Name: 2.2.13 for initrd on TQM850L 5946 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5947 Data Size: 335725 Bytes = 327 kB = 0 MB 5948 Load Address: 00000000 5949 Entry Point: 0000000c 5950 Verifying Checksum ... OK 5951 5952 ## Checking Image at 40200000 ... 5953 Image Name: Simple Ramdisk Image 5954 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 5955 Data Size: 566530 Bytes = 553 kB = 0 MB 5956 Load Address: 00000000 5957 Entry Point: 00000000 5958 Verifying Checksum ... OK 5959 5960 => bootm 40100000 40200000 5961 ## Booting Linux kernel at 40100000 ... 5962 Image Name: 2.2.13 for initrd on TQM850L 5963 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5964 Data Size: 335725 Bytes = 327 kB = 0 MB 5965 Load Address: 00000000 5966 Entry Point: 0000000c 5967 Verifying Checksum ... OK 5968 Uncompressing Kernel Image ... OK 5969 ## Loading RAMDisk Image at 40200000 ... 5970 Image Name: Simple Ramdisk Image 5971 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 5972 Data Size: 566530 Bytes = 553 kB = 0 MB 5973 Load Address: 00000000 5974 Entry Point: 00000000 5975 Verifying Checksum ... OK 5976 Loading Ramdisk ... OK 5977 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 5978 Boot arguments: root=/dev/ram 5979 time_init: decrementer frequency = 187500000/60 5980 Calibrating delay loop... 49.77 BogoMIPS 5981 ... 5982 RAMDISK: Compressed image found at block 0 5983 VFS: Mounted root (ext2 filesystem). 5984 5985 bash# 5986 5987Boot Linux and pass a flat device tree: 5988----------- 5989 5990First, U-Boot must be compiled with the appropriate defines. See the section 5991titled "Linux Kernel Interface" above for a more in depth explanation. The 5992following is an example of how to start a kernel and pass an updated 5993flat device tree: 5994 5995=> print oftaddr 5996oftaddr=0x300000 5997=> print oft 5998oft=oftrees/mpc8540ads.dtb 5999=> tftp $oftaddr $oft 6000Speed: 1000, full duplex 6001Using TSEC0 device 6002TFTP from server 192.168.1.1; our IP address is 192.168.1.101 6003Filename 'oftrees/mpc8540ads.dtb'. 6004Load address: 0x300000 6005Loading: # 6006done 6007Bytes transferred = 4106 (100a hex) 6008=> tftp $loadaddr $bootfile 6009Speed: 1000, full duplex 6010Using TSEC0 device 6011TFTP from server 192.168.1.1; our IP address is 192.168.1.2 6012Filename 'uImage'. 6013Load address: 0x200000 6014Loading:############ 6015done 6016Bytes transferred = 1029407 (fb51f hex) 6017=> print loadaddr 6018loadaddr=200000 6019=> print oftaddr 6020oftaddr=0x300000 6021=> bootm $loadaddr - $oftaddr 6022## Booting image at 00200000 ... 6023 Image Name: Linux-2.6.17-dirty 6024 Image Type: PowerPC Linux Kernel Image (gzip compressed) 6025 Data Size: 1029343 Bytes = 1005.2 kB 6026 Load Address: 00000000 6027 Entry Point: 00000000 6028 Verifying Checksum ... OK 6029 Uncompressing Kernel Image ... OK 6030Booting using flat device tree at 0x300000 6031Using MPC85xx ADS machine description 6032Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb 6033[snip] 6034 6035 6036More About U-Boot Image Types: 6037------------------------------ 6038 6039U-Boot supports the following image types: 6040 6041 "Standalone Programs" are directly runnable in the environment 6042 provided by U-Boot; it is expected that (if they behave 6043 well) you can continue to work in U-Boot after return from 6044 the Standalone Program. 6045 "OS Kernel Images" are usually images of some Embedded OS which 6046 will take over control completely. Usually these programs 6047 will install their own set of exception handlers, device 6048 drivers, set up the MMU, etc. - this means, that you cannot 6049 expect to re-enter U-Boot except by resetting the CPU. 6050 "RAMDisk Images" are more or less just data blocks, and their 6051 parameters (address, size) are passed to an OS kernel that is 6052 being started. 6053 "Multi-File Images" contain several images, typically an OS 6054 (Linux) kernel image and one or more data images like 6055 RAMDisks. This construct is useful for instance when you want 6056 to boot over the network using BOOTP etc., where the boot 6057 server provides just a single image file, but you want to get 6058 for instance an OS kernel and a RAMDisk image. 6059 6060 "Multi-File Images" start with a list of image sizes, each 6061 image size (in bytes) specified by an "uint32_t" in network 6062 byte order. This list is terminated by an "(uint32_t)0". 6063 Immediately after the terminating 0 follow the images, one by 6064 one, all aligned on "uint32_t" boundaries (size rounded up to 6065 a multiple of 4 bytes). 6066 6067 "Firmware Images" are binary images containing firmware (like 6068 U-Boot or FPGA images) which usually will be programmed to 6069 flash memory. 6070 6071 "Script files" are command sequences that will be executed by 6072 U-Boot's command interpreter; this feature is especially 6073 useful when you configure U-Boot to use a real shell (hush) 6074 as command interpreter. 6075 6076Booting the Linux zImage: 6077------------------------- 6078 6079On some platforms, it's possible to boot Linux zImage. This is done 6080using the "bootz" command. The syntax of "bootz" command is the same 6081as the syntax of "bootm" command. 6082 6083Note, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply 6084kernel with raw initrd images. The syntax is slightly different, the 6085address of the initrd must be augmented by it's size, in the following 6086format: "<initrd addres>:<initrd size>". 6087 6088 6089Standalone HOWTO: 6090================= 6091 6092One of the features of U-Boot is that you can dynamically load and 6093run "standalone" applications, which can use some resources of 6094U-Boot like console I/O functions or interrupt services. 6095 6096Two simple examples are included with the sources: 6097 6098"Hello World" Demo: 6099------------------- 6100 6101'examples/hello_world.c' contains a small "Hello World" Demo 6102application; it is automatically compiled when you build U-Boot. 6103It's configured to run at address 0x00040004, so you can play with it 6104like that: 6105 6106 => loads 6107 ## Ready for S-Record download ... 6108 ~>examples/hello_world.srec 6109 1 2 3 4 5 6 7 8 9 10 11 ... 6110 [file transfer complete] 6111 [connected] 6112 ## Start Addr = 0x00040004 6113 6114 => go 40004 Hello World! This is a test. 6115 ## Starting application at 0x00040004 ... 6116 Hello World 6117 argc = 7 6118 argv[0] = "40004" 6119 argv[1] = "Hello" 6120 argv[2] = "World!" 6121 argv[3] = "This" 6122 argv[4] = "is" 6123 argv[5] = "a" 6124 argv[6] = "test." 6125 argv[7] = "<NULL>" 6126 Hit any key to exit ... 6127 6128 ## Application terminated, rc = 0x0 6129 6130Another example, which demonstrates how to register a CPM interrupt 6131handler with the U-Boot code, can be found in 'examples/timer.c'. 6132Here, a CPM timer is set up to generate an interrupt every second. 6133The interrupt service routine is trivial, just printing a '.' 6134character, but this is just a demo program. The application can be 6135controlled by the following keys: 6136 6137 ? - print current values og the CPM Timer registers 6138 b - enable interrupts and start timer 6139 e - stop timer and disable interrupts 6140 q - quit application 6141 6142 => loads 6143 ## Ready for S-Record download ... 6144 ~>examples/timer.srec 6145 1 2 3 4 5 6 7 8 9 10 11 ... 6146 [file transfer complete] 6147 [connected] 6148 ## Start Addr = 0x00040004 6149 6150 => go 40004 6151 ## Starting application at 0x00040004 ... 6152 TIMERS=0xfff00980 6153 Using timer 1 6154 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0 6155 6156Hit 'b': 6157 [q, b, e, ?] Set interval 1000000 us 6158 Enabling timer 6159Hit '?': 6160 [q, b, e, ?] ........ 6161 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0 6162Hit '?': 6163 [q, b, e, ?] . 6164 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0 6165Hit '?': 6166 [q, b, e, ?] . 6167 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0 6168Hit '?': 6169 [q, b, e, ?] . 6170 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0 6171Hit 'e': 6172 [q, b, e, ?] ...Stopping timer 6173Hit 'q': 6174 [q, b, e, ?] ## Application terminated, rc = 0x0 6175 6176 6177Minicom warning: 6178================ 6179 6180Over time, many people have reported problems when trying to use the 6181"minicom" terminal emulation program for serial download. I (wd) 6182consider minicom to be broken, and recommend not to use it. Under 6183Unix, I recommend to use C-Kermit for general purpose use (and 6184especially for kermit binary protocol download ("loadb" command), and 6185use "cu" for S-Record download ("loads" command). See 6186http://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3. 6187for help with kermit. 6188 6189 6190Nevertheless, if you absolutely want to use it try adding this 6191configuration to your "File transfer protocols" section: 6192 6193 Name Program Name U/D FullScr IO-Red. Multi 6194 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N 6195 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N 6196 6197 6198NetBSD Notes: 6199============= 6200 6201Starting at version 0.9.2, U-Boot supports NetBSD both as host 6202(build U-Boot) and target system (boots NetBSD/mpc8xx). 6203 6204Building requires a cross environment; it is known to work on 6205NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also 6206need gmake since the Makefiles are not compatible with BSD make). 6207Note that the cross-powerpc package does not install include files; 6208attempting to build U-Boot will fail because <machine/ansi.h> is 6209missing. This file has to be installed and patched manually: 6210 6211 # cd /usr/pkg/cross/powerpc-netbsd/include 6212 # mkdir powerpc 6213 # ln -s powerpc machine 6214 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h 6215 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST 6216 6217Native builds *don't* work due to incompatibilities between native 6218and U-Boot include files. 6219 6220Booting assumes that (the first part of) the image booted is a 6221stage-2 loader which in turn loads and then invokes the kernel 6222proper. Loader sources will eventually appear in the NetBSD source 6223tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the 6224meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz 6225 6226 6227Implementation Internals: 6228========================= 6229 6230The following is not intended to be a complete description of every 6231implementation detail. However, it should help to understand the 6232inner workings of U-Boot and make it easier to port it to custom 6233hardware. 6234 6235 6236Initial Stack, Global Data: 6237--------------------------- 6238 6239The implementation of U-Boot is complicated by the fact that U-Boot 6240starts running out of ROM (flash memory), usually without access to 6241system RAM (because the memory controller is not initialized yet). 6242This means that we don't have writable Data or BSS segments, and BSS 6243is not initialized as zero. To be able to get a C environment working 6244at all, we have to allocate at least a minimal stack. Implementation 6245options for this are defined and restricted by the CPU used: Some CPU 6246models provide on-chip memory (like the IMMR area on MPC8xx and 6247MPC826x processors), on others (parts of) the data cache can be 6248locked as (mis-) used as memory, etc. 6249 6250 Chris Hallinan posted a good summary of these issues to the 6251 U-Boot mailing list: 6252 6253 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)? 6254 From: "Chris Hallinan" <clh@net1plus.com> 6255 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET) 6256 ... 6257 6258 Correct me if I'm wrong, folks, but the way I understand it 6259 is this: Using DCACHE as initial RAM for Stack, etc, does not 6260 require any physical RAM backing up the cache. The cleverness 6261 is that the cache is being used as a temporary supply of 6262 necessary storage before the SDRAM controller is setup. It's 6263 beyond the scope of this list to explain the details, but you 6264 can see how this works by studying the cache architecture and 6265 operation in the architecture and processor-specific manuals. 6266 6267 OCM is On Chip Memory, which I believe the 405GP has 4K. It 6268 is another option for the system designer to use as an 6269 initial stack/RAM area prior to SDRAM being available. Either 6270 option should work for you. Using CS 4 should be fine if your 6271 board designers haven't used it for something that would 6272 cause you grief during the initial boot! It is frequently not 6273 used. 6274 6275 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere 6276 with your processor/board/system design. The default value 6277 you will find in any recent u-boot distribution in 6278 walnut.h should work for you. I'd set it to a value larger 6279 than your SDRAM module. If you have a 64MB SDRAM module, set 6280 it above 400_0000. Just make sure your board has no resources 6281 that are supposed to respond to that address! That code in 6282 start.S has been around a while and should work as is when 6283 you get the config right. 6284 6285 -Chris Hallinan 6286 DS4.COM, Inc. 6287 6288It is essential to remember this, since it has some impact on the C 6289code for the initialization procedures: 6290 6291* Initialized global data (data segment) is read-only. Do not attempt 6292 to write it. 6293 6294* Do not use any uninitialized global data (or implicitly initialized 6295 as zero data - BSS segment) at all - this is undefined, initiali- 6296 zation is performed later (when relocating to RAM). 6297 6298* Stack space is very limited. Avoid big data buffers or things like 6299 that. 6300 6301Having only the stack as writable memory limits means we cannot use 6302normal global data to share information between the code. But it 6303turned out that the implementation of U-Boot can be greatly 6304simplified by making a global data structure (gd_t) available to all 6305functions. We could pass a pointer to this data as argument to _all_ 6306functions, but this would bloat the code. Instead we use a feature of 6307the GCC compiler (Global Register Variables) to share the data: we 6308place a pointer (gd) to the global data into a register which we 6309reserve for this purpose. 6310 6311When choosing a register for such a purpose we are restricted by the 6312relevant (E)ABI specifications for the current architecture, and by 6313GCC's implementation. 6314 6315For PowerPC, the following registers have specific use: 6316 R1: stack pointer 6317 R2: reserved for system use 6318 R3-R4: parameter passing and return values 6319 R5-R10: parameter passing 6320 R13: small data area pointer 6321 R30: GOT pointer 6322 R31: frame pointer 6323 6324 (U-Boot also uses R12 as internal GOT pointer. r12 6325 is a volatile register so r12 needs to be reset when 6326 going back and forth between asm and C) 6327 6328 ==> U-Boot will use R2 to hold a pointer to the global data 6329 6330 Note: on PPC, we could use a static initializer (since the 6331 address of the global data structure is known at compile time), 6332 but it turned out that reserving a register results in somewhat 6333 smaller code - although the code savings are not that big (on 6334 average for all boards 752 bytes for the whole U-Boot image, 6335 624 text + 127 data). 6336 6337On Blackfin, the normal C ABI (except for P3) is followed as documented here: 6338 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface 6339 6340 ==> U-Boot will use P3 to hold a pointer to the global data 6341 6342On ARM, the following registers are used: 6343 6344 R0: function argument word/integer result 6345 R1-R3: function argument word 6346 R9: platform specific 6347 R10: stack limit (used only if stack checking is enabled) 6348 R11: argument (frame) pointer 6349 R12: temporary workspace 6350 R13: stack pointer 6351 R14: link register 6352 R15: program counter 6353 6354 ==> U-Boot will use R9 to hold a pointer to the global data 6355 6356 Note: on ARM, only R_ARM_RELATIVE relocations are supported. 6357 6358On Nios II, the ABI is documented here: 6359 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf 6360 6361 ==> U-Boot will use gp to hold a pointer to the global data 6362 6363 Note: on Nios II, we give "-G0" option to gcc and don't use gp 6364 to access small data sections, so gp is free. 6365 6366On NDS32, the following registers are used: 6367 6368 R0-R1: argument/return 6369 R2-R5: argument 6370 R15: temporary register for assembler 6371 R16: trampoline register 6372 R28: frame pointer (FP) 6373 R29: global pointer (GP) 6374 R30: link register (LP) 6375 R31: stack pointer (SP) 6376 PC: program counter (PC) 6377 6378 ==> U-Boot will use R10 to hold a pointer to the global data 6379 6380NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope, 6381or current versions of GCC may "optimize" the code too much. 6382 6383Memory Management: 6384------------------ 6385 6386U-Boot runs in system state and uses physical addresses, i.e. the 6387MMU is not used either for address mapping nor for memory protection. 6388 6389The available memory is mapped to fixed addresses using the memory 6390controller. In this process, a contiguous block is formed for each 6391memory type (Flash, SDRAM, SRAM), even when it consists of several 6392physical memory banks. 6393 6394U-Boot is installed in the first 128 kB of the first Flash bank (on 6395TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After 6396booting and sizing and initializing DRAM, the code relocates itself 6397to the upper end of DRAM. Immediately below the U-Boot code some 6398memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN 6399configuration setting]. Below that, a structure with global Board 6400Info data is placed, followed by the stack (growing downward). 6401 6402Additionally, some exception handler code is copied to the low 8 kB 6403of DRAM (0x00000000 ... 0x00001FFF). 6404 6405So a typical memory configuration with 16 MB of DRAM could look like 6406this: 6407 6408 0x0000 0000 Exception Vector code 6409 : 6410 0x0000 1FFF 6411 0x0000 2000 Free for Application Use 6412 : 6413 : 6414 6415 : 6416 : 6417 0x00FB FF20 Monitor Stack (Growing downward) 6418 0x00FB FFAC Board Info Data and permanent copy of global data 6419 0x00FC 0000 Malloc Arena 6420 : 6421 0x00FD FFFF 6422 0x00FE 0000 RAM Copy of Monitor Code 6423 ... eventually: LCD or video framebuffer 6424 ... eventually: pRAM (Protected RAM - unchanged by reset) 6425 0x00FF FFFF [End of RAM] 6426 6427 6428System Initialization: 6429---------------------- 6430 6431In the reset configuration, U-Boot starts at the reset entry point 6432(on most PowerPC systems at address 0x00000100). Because of the reset 6433configuration for CS0# this is a mirror of the on board Flash memory. 6434To be able to re-map memory U-Boot then jumps to its link address. 6435To be able to implement the initialization code in C, a (small!) 6436initial stack is set up in the internal Dual Ported RAM (in case CPUs 6437which provide such a feature like MPC8xx or MPC8260), or in a locked 6438part of the data cache. After that, U-Boot initializes the CPU core, 6439the caches and the SIU. 6440 6441Next, all (potentially) available memory banks are mapped using a 6442preliminary mapping. For example, we put them on 512 MB boundaries 6443(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash 6444on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is 6445programmed for SDRAM access. Using the temporary configuration, a 6446simple memory test is run that determines the size of the SDRAM 6447banks. 6448 6449When there is more than one SDRAM bank, and the banks are of 6450different size, the largest is mapped first. For equal size, the first 6451bank (CS2#) is mapped first. The first mapping is always for address 64520x00000000, with any additional banks following immediately to create 6453contiguous memory starting from 0. 6454 6455Then, the monitor installs itself at the upper end of the SDRAM area 6456and allocates memory for use by malloc() and for the global Board 6457Info data; also, the exception vector code is copied to the low RAM 6458pages, and the final stack is set up. 6459 6460Only after this relocation will you have a "normal" C environment; 6461until that you are restricted in several ways, mostly because you are 6462running from ROM, and because the code will have to be relocated to a 6463new address in RAM. 6464 6465 6466U-Boot Porting Guide: 6467---------------------- 6468 6469[Based on messages by Jerry Van Baren in the U-Boot-Users mailing 6470list, October 2002] 6471 6472 6473int main(int argc, char *argv[]) 6474{ 6475 sighandler_t no_more_time; 6476 6477 signal(SIGALRM, no_more_time); 6478 alarm(PROJECT_DEADLINE - toSec (3 * WEEK)); 6479 6480 if (available_money > available_manpower) { 6481 Pay consultant to port U-Boot; 6482 return 0; 6483 } 6484 6485 Download latest U-Boot source; 6486 6487 Subscribe to u-boot mailing list; 6488 6489 if (clueless) 6490 email("Hi, I am new to U-Boot, how do I get started?"); 6491 6492 while (learning) { 6493 Read the README file in the top level directory; 6494 Read http://www.denx.de/twiki/bin/view/DULG/Manual; 6495 Read applicable doc/*.README; 6496 Read the source, Luke; 6497 /* find . -name "*.[chS]" | xargs grep -i <keyword> */ 6498 } 6499 6500 if (available_money > toLocalCurrency ($2500)) 6501 Buy a BDI3000; 6502 else 6503 Add a lot of aggravation and time; 6504 6505 if (a similar board exists) { /* hopefully... */ 6506 cp -a board/<similar> board/<myboard> 6507 cp include/configs/<similar>.h include/configs/<myboard>.h 6508 } else { 6509 Create your own board support subdirectory; 6510 Create your own board include/configs/<myboard>.h file; 6511 } 6512 Edit new board/<myboard> files 6513 Edit new include/configs/<myboard>.h 6514 6515 while (!accepted) { 6516 while (!running) { 6517 do { 6518 Add / modify source code; 6519 } until (compiles); 6520 Debug; 6521 if (clueless) 6522 email("Hi, I am having problems..."); 6523 } 6524 Send patch file to the U-Boot email list; 6525 if (reasonable critiques) 6526 Incorporate improvements from email list code review; 6527 else 6528 Defend code as written; 6529 } 6530 6531 return 0; 6532} 6533 6534void no_more_time (int sig) 6535{ 6536 hire_a_guru(); 6537} 6538 6539 6540Coding Standards: 6541----------------- 6542 6543All contributions to U-Boot should conform to the Linux kernel 6544coding style; see the file "Documentation/CodingStyle" and the script 6545"scripts/Lindent" in your Linux kernel source directory. 6546 6547Source files originating from a different project (for example the 6548MTD subsystem) are generally exempt from these guidelines and are not 6549reformatted to ease subsequent migration to newer versions of those 6550sources. 6551 6552Please note that U-Boot is implemented in C (and to some small parts in 6553Assembler); no C++ is used, so please do not use C++ style comments (//) 6554in your code. 6555 6556Please also stick to the following formatting rules: 6557- remove any trailing white space 6558- use TAB characters for indentation and vertical alignment, not spaces 6559- make sure NOT to use DOS '\r\n' line feeds 6560- do not add more than 2 consecutive empty lines to source files 6561- do not add trailing empty lines to source files 6562 6563Submissions which do not conform to the standards may be returned 6564with a request to reformat the changes. 6565 6566 6567Submitting Patches: 6568------------------- 6569 6570Since the number of patches for U-Boot is growing, we need to 6571establish some rules. Submissions which do not conform to these rules 6572may be rejected, even when they contain important and valuable stuff. 6573 6574Please see http://www.denx.de/wiki/U-Boot/Patches for details. 6575 6576Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>; 6577see http://lists.denx.de/mailman/listinfo/u-boot 6578 6579When you send a patch, please include the following information with 6580it: 6581 6582* For bug fixes: a description of the bug and how your patch fixes 6583 this bug. Please try to include a way of demonstrating that the 6584 patch actually fixes something. 6585 6586* For new features: a description of the feature and your 6587 implementation. 6588 6589* A CHANGELOG entry as plaintext (separate from the patch) 6590 6591* For major contributions, add a MAINTAINERS file with your 6592 information and associated file and directory references. 6593 6594* When you add support for a new board, don't forget to add a 6595 maintainer e-mail address to the boards.cfg file, too. 6596 6597* If your patch adds new configuration options, don't forget to 6598 document these in the README file. 6599 6600* The patch itself. If you are using git (which is *strongly* 6601 recommended) you can easily generate the patch using the 6602 "git format-patch". If you then use "git send-email" to send it to 6603 the U-Boot mailing list, you will avoid most of the common problems 6604 with some other mail clients. 6605 6606 If you cannot use git, use "diff -purN OLD NEW". If your version of 6607 diff does not support these options, then get the latest version of 6608 GNU diff. 6609 6610 The current directory when running this command shall be the parent 6611 directory of the U-Boot source tree (i. e. please make sure that 6612 your patch includes sufficient directory information for the 6613 affected files). 6614 6615 We prefer patches as plain text. MIME attachments are discouraged, 6616 and compressed attachments must not be used. 6617 6618* If one logical set of modifications affects or creates several 6619 files, all these changes shall be submitted in a SINGLE patch file. 6620 6621* Changesets that contain different, unrelated modifications shall be 6622 submitted as SEPARATE patches, one patch per changeset. 6623 6624 6625Notes: 6626 6627* Before sending the patch, run the MAKEALL script on your patched 6628 source tree and make sure that no errors or warnings are reported 6629 for any of the boards. 6630 6631* Keep your modifications to the necessary minimum: A patch 6632 containing several unrelated changes or arbitrary reformats will be 6633 returned with a request to re-formatting / split it. 6634 6635* If you modify existing code, make sure that your new code does not 6636 add to the memory footprint of the code ;-) Small is beautiful! 6637 When adding new features, these should compile conditionally only 6638 (using #ifdef), and the resulting code with the new feature 6639 disabled must not need more memory than the old code without your 6640 modification. 6641 6642* Remember that there is a size limit of 100 kB per message on the 6643 u-boot mailing list. Bigger patches will be moderated. If they are 6644 reasonable and not too big, they will be acknowledged. But patches 6645 bigger than the size limit should be avoided. 6646