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 candidate 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 /m68k Files generic to m68k architecture 141 /microblaze Files generic to microblaze architecture 142 /mips Files generic to MIPS architecture 143 /nds32 Files generic to NDS32 architecture 144 /nios2 Files generic to Altera NIOS2 architecture 145 /openrisc Files generic to OpenRISC architecture 146 /powerpc Files generic to PowerPC architecture 147 /sandbox Files generic to HW-independent "sandbox" 148 /sh Files generic to SH architecture 149 /x86 Files generic to x86 architecture 150/api Machine/arch independent API for external apps 151/board Board dependent files 152/cmd U-Boot commands functions 153/common Misc architecture independent functions 154/configs Board default configuration files 155/disk Code for disk drive partition handling 156/doc Documentation (don't expect too much) 157/drivers Commonly used device drivers 158/dts Contains Makefile for building internal U-Boot fdt. 159/examples Example code for standalone applications, etc. 160/fs Filesystem code (cramfs, ext2, jffs2, etc.) 161/include Header Files 162/lib Library routines generic to all architectures 163/Licenses Various license files 164/net Networking code 165/post Power On Self Test 166/scripts Various build scripts and Makefiles 167/test Various unit test files 168/tools Tools to build S-Record or U-Boot images, etc. 169 170Software Configuration: 171======================= 172 173Configuration is usually done using C preprocessor defines; the 174rationale behind that is to avoid dead code whenever possible. 175 176There are two classes of configuration variables: 177 178* Configuration _OPTIONS_: 179 These are selectable by the user and have names beginning with 180 "CONFIG_". 181 182* Configuration _SETTINGS_: 183 These depend on the hardware etc. and should not be meddled with if 184 you don't know what you're doing; they have names beginning with 185 "CONFIG_SYS_". 186 187Previously, all configuration was done by hand, which involved creating 188symbolic links and editing configuration files manually. More recently, 189U-Boot has added the Kbuild infrastructure used by the Linux kernel, 190allowing you to use the "make menuconfig" command to configure your 191build. 192 193 194Selection of Processor Architecture and Board Type: 195--------------------------------------------------- 196 197For all supported boards there are ready-to-use default 198configurations available; just type "make <board_name>_defconfig". 199 200Example: For a TQM823L module type: 201 202 cd u-boot 203 make TQM823L_defconfig 204 205Note: If you're looking for the default configuration file for a board 206you're sure used to be there but is now missing, check the file 207doc/README.scrapyard for a list of no longer supported boards. 208 209Sandbox Environment: 210-------------------- 211 212U-Boot can be built natively to run on a Linux host using the 'sandbox' 213board. This allows feature development which is not board- or architecture- 214specific to be undertaken on a native platform. The sandbox is also used to 215run some of U-Boot's tests. 216 217See board/sandbox/README.sandbox for more details. 218 219 220Board Initialisation Flow: 221-------------------------- 222 223This is the intended start-up flow for boards. This should apply for both 224SPL and U-Boot proper (i.e. they both follow the same rules). 225 226Note: "SPL" stands for "Secondary Program Loader," which is explained in 227more detail later in this file. 228 229At present, SPL mostly uses a separate code path, but the function names 230and roles of each function are the same. Some boards or architectures 231may not conform to this. At least most ARM boards which use 232CONFIG_SPL_FRAMEWORK conform to this. 233 234Execution typically starts with an architecture-specific (and possibly 235CPU-specific) start.S file, such as: 236 237 - arch/arm/cpu/armv7/start.S 238 - arch/powerpc/cpu/mpc83xx/start.S 239 - arch/mips/cpu/start.S 240 241and so on. From there, three functions are called; the purpose and 242limitations of each of these functions are described below. 243 244lowlevel_init(): 245 - purpose: essential init to permit execution to reach board_init_f() 246 - no global_data or BSS 247 - there is no stack (ARMv7 may have one but it will soon be removed) 248 - must not set up SDRAM or use console 249 - must only do the bare minimum to allow execution to continue to 250 board_init_f() 251 - this is almost never needed 252 - return normally from this function 253 254board_init_f(): 255 - purpose: set up the machine ready for running board_init_r(): 256 i.e. SDRAM and serial UART 257 - global_data is available 258 - stack is in SRAM 259 - BSS is not available, so you cannot use global/static variables, 260 only stack variables and global_data 261 262 Non-SPL-specific notes: 263 - dram_init() is called to set up DRAM. If already done in SPL this 264 can do nothing 265 266 SPL-specific notes: 267 - you can override the entire board_init_f() function with your own 268 version as needed. 269 - preloader_console_init() can be called here in extremis 270 - should set up SDRAM, and anything needed to make the UART work 271 - these is no need to clear BSS, it will be done by crt0.S 272 - must return normally from this function (don't call board_init_r() 273 directly) 274 275Here the BSS is cleared. For SPL, if CONFIG_SPL_STACK_R is defined, then at 276this point the stack and global_data are relocated to below 277CONFIG_SPL_STACK_R_ADDR. For non-SPL, U-Boot is relocated to run at the top of 278memory. 279 280board_init_r(): 281 - purpose: main execution, common code 282 - global_data is available 283 - SDRAM is available 284 - BSS is available, all static/global variables can be used 285 - execution eventually continues to main_loop() 286 287 Non-SPL-specific notes: 288 - U-Boot is relocated to the top of memory and is now running from 289 there. 290 291 SPL-specific notes: 292 - stack is optionally in SDRAM, if CONFIG_SPL_STACK_R is defined and 293 CONFIG_SPL_STACK_R_ADDR points into SDRAM 294 - preloader_console_init() can be called here - typically this is 295 done by defining CONFIG_SPL_BOARD_INIT and then supplying a 296 spl_board_init() function containing this call 297 - loads U-Boot or (in falcon mode) Linux 298 299 300 301Configuration Options: 302---------------------- 303 304Configuration depends on the combination of board and CPU type; all 305such information is kept in a configuration file 306"include/configs/<board_name>.h". 307 308Example: For a TQM823L module, all configuration settings are in 309"include/configs/TQM823L.h". 310 311 312Many of the options are named exactly as the corresponding Linux 313kernel configuration options. The intention is to make it easier to 314build a config tool - later. 315 316 317The following options need to be configured: 318 319- CPU Type: Define exactly one, e.g. CONFIG_MPC85XX. 320 321- Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS. 322 323- CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined) 324 Define exactly one, e.g. CONFIG_ATSTK1002 325 326- Marvell Family Member 327 CONFIG_SYS_MVFS - define it if you want to enable 328 multiple fs option at one time 329 for marvell soc family 330 331- 8xx CPU Options: (if using an MPC8xx CPU) 332 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if 333 get_gclk_freq() cannot work 334 e.g. if there is no 32KHz 335 reference PIT/RTC clock 336 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK 337 or XTAL/EXTAL) 338 339- 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU): 340 CONFIG_SYS_8xx_CPUCLK_MIN 341 CONFIG_SYS_8xx_CPUCLK_MAX 342 CONFIG_8xx_CPUCLK_DEFAULT 343 See doc/README.MPC866 344 345 CONFIG_SYS_MEASURE_CPUCLK 346 347 Define this to measure the actual CPU clock instead 348 of relying on the correctness of the configured 349 values. Mostly useful for board bringup to make sure 350 the PLL is locked at the intended frequency. Note 351 that this requires a (stable) reference clock (32 kHz 352 RTC clock or CONFIG_SYS_8XX_XIN) 353 354 CONFIG_SYS_DELAYED_ICACHE 355 356 Define this option if you want to enable the 357 ICache only when Code runs from RAM. 358 359- 85xx CPU Options: 360 CONFIG_SYS_PPC64 361 362 Specifies that the core is a 64-bit PowerPC implementation (implements 363 the "64" category of the Power ISA). This is necessary for ePAPR 364 compliance, among other possible reasons. 365 366 CONFIG_SYS_FSL_TBCLK_DIV 367 368 Defines the core time base clock divider ratio compared to the 369 system clock. On most PQ3 devices this is 8, on newer QorIQ 370 devices it can be 16 or 32. The ratio varies from SoC to Soc. 371 372 CONFIG_SYS_FSL_PCIE_COMPAT 373 374 Defines the string to utilize when trying to match PCIe device 375 tree nodes for the given platform. 376 377 CONFIG_SYS_FSL_ERRATUM_A004510 378 379 Enables a workaround for erratum A004510. If set, 380 then CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV and 381 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY must be set. 382 383 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV 384 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 (optional) 385 386 Defines one or two SoC revisions (low 8 bits of SVR) 387 for which the A004510 workaround should be applied. 388 389 The rest of SVR is either not relevant to the decision 390 of whether the erratum is present (e.g. p2040 versus 391 p2041) or is implied by the build target, which controls 392 whether CONFIG_SYS_FSL_ERRATUM_A004510 is set. 393 394 See Freescale App Note 4493 for more information about 395 this erratum. 396 397 CONFIG_A003399_NOR_WORKAROUND 398 Enables a workaround for IFC erratum A003399. It is only 399 required during NOR boot. 400 401 CONFIG_A008044_WORKAROUND 402 Enables a workaround for T1040/T1042 erratum A008044. It is only 403 required during NAND boot and valid for Rev 1.0 SoC revision 404 405 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY 406 407 This is the value to write into CCSR offset 0x18600 408 according to the A004510 workaround. 409 410 CONFIG_SYS_FSL_DSP_DDR_ADDR 411 This value denotes start offset of DDR memory which is 412 connected exclusively to the DSP cores. 413 414 CONFIG_SYS_FSL_DSP_M2_RAM_ADDR 415 This value denotes start offset of M2 memory 416 which is directly connected to the DSP core. 417 418 CONFIG_SYS_FSL_DSP_M3_RAM_ADDR 419 This value denotes start offset of M3 memory which is directly 420 connected to the DSP core. 421 422 CONFIG_SYS_FSL_DSP_CCSRBAR_DEFAULT 423 This value denotes start offset of DSP CCSR space. 424 425 CONFIG_SYS_FSL_SINGLE_SOURCE_CLK 426 Single Source Clock is clocking mode present in some of FSL SoC's. 427 In this mode, a single differential clock is used to supply 428 clocks to the sysclock, ddrclock and usbclock. 429 430 CONFIG_SYS_CPC_REINIT_F 431 This CONFIG is defined when the CPC is configured as SRAM at the 432 time of U-Boot entry and is required to be re-initialized. 433 434 CONFIG_DEEP_SLEEP 435 Indicates this SoC supports deep sleep feature. If deep sleep is 436 supported, core will start to execute uboot when wakes up. 437 438- Generic CPU options: 439 CONFIG_SYS_GENERIC_GLOBAL_DATA 440 Defines global data is initialized in generic board board_init_f(). 441 If this macro is defined, global data is created and cleared in 442 generic board board_init_f(). Without this macro, architecture/board 443 should initialize global data before calling board_init_f(). 444 445 CONFIG_SYS_BIG_ENDIAN, CONFIG_SYS_LITTLE_ENDIAN 446 447 Defines the endianess of the CPU. Implementation of those 448 values is arch specific. 449 450 CONFIG_SYS_FSL_DDR 451 Freescale DDR driver in use. This type of DDR controller is 452 found in mpc83xx, mpc85xx, mpc86xx as well as some ARM core 453 SoCs. 454 455 CONFIG_SYS_FSL_DDR_ADDR 456 Freescale DDR memory-mapped register base. 457 458 CONFIG_SYS_FSL_DDR_EMU 459 Specify emulator support for DDR. Some DDR features such as 460 deskew training are not available. 461 462 CONFIG_SYS_FSL_DDRC_GEN1 463 Freescale DDR1 controller. 464 465 CONFIG_SYS_FSL_DDRC_GEN2 466 Freescale DDR2 controller. 467 468 CONFIG_SYS_FSL_DDRC_GEN3 469 Freescale DDR3 controller. 470 471 CONFIG_SYS_FSL_DDRC_GEN4 472 Freescale DDR4 controller. 473 474 CONFIG_SYS_FSL_DDRC_ARM_GEN3 475 Freescale DDR3 controller for ARM-based SoCs. 476 477 CONFIG_SYS_FSL_DDR1 478 Board config to use DDR1. It can be enabled for SoCs with 479 Freescale DDR1 or DDR2 controllers, depending on the board 480 implemetation. 481 482 CONFIG_SYS_FSL_DDR2 483 Board config to use DDR2. It can be enabled for SoCs with 484 Freescale DDR2 or DDR3 controllers, depending on the board 485 implementation. 486 487 CONFIG_SYS_FSL_DDR3 488 Board config to use DDR3. It can be enabled for SoCs with 489 Freescale DDR3 or DDR3L controllers. 490 491 CONFIG_SYS_FSL_DDR3L 492 Board config to use DDR3L. It can be enabled for SoCs with 493 DDR3L controllers. 494 495 CONFIG_SYS_FSL_DDR4 496 Board config to use DDR4. It can be enabled for SoCs with 497 DDR4 controllers. 498 499 CONFIG_SYS_FSL_IFC_BE 500 Defines the IFC controller register space as Big Endian 501 502 CONFIG_SYS_FSL_IFC_LE 503 Defines the IFC controller register space as Little Endian 504 505 CONFIG_SYS_FSL_IFC_CLK_DIV 506 Defines divider of platform clock(clock input to IFC controller). 507 508 CONFIG_SYS_FSL_LBC_CLK_DIV 509 Defines divider of platform clock(clock input to eLBC controller). 510 511 CONFIG_SYS_FSL_PBL_PBI 512 It enables addition of RCW (Power on reset configuration) in built image. 513 Please refer doc/README.pblimage for more details 514 515 CONFIG_SYS_FSL_PBL_RCW 516 It adds PBI(pre-boot instructions) commands in u-boot build image. 517 PBI commands can be used to configure SoC before it starts the execution. 518 Please refer doc/README.pblimage for more details 519 520 CONFIG_SPL_FSL_PBL 521 It adds a target to create boot binary having SPL binary in PBI format 522 concatenated with u-boot binary. 523 524 CONFIG_SYS_FSL_DDR_BE 525 Defines the DDR controller register space as Big Endian 526 527 CONFIG_SYS_FSL_DDR_LE 528 Defines the DDR controller register space as Little Endian 529 530 CONFIG_SYS_FSL_DDR_SDRAM_BASE_PHY 531 Physical address from the view of DDR controllers. It is the 532 same as CONFIG_SYS_DDR_SDRAM_BASE for all Power SoCs. But 533 it could be different for ARM SoCs. 534 535 CONFIG_SYS_FSL_DDR_INTLV_256B 536 DDR controller interleaving on 256-byte. This is a special 537 interleaving mode, handled by Dickens for Freescale layerscape 538 SoCs with ARM core. 539 540 CONFIG_SYS_FSL_DDR_MAIN_NUM_CTRLS 541 Number of controllers used as main memory. 542 543 CONFIG_SYS_FSL_OTHER_DDR_NUM_CTRLS 544 Number of controllers used for other than main memory. 545 546 CONFIG_SYS_FSL_HAS_DP_DDR 547 Defines the SoC has DP-DDR used for DPAA. 548 549 CONFIG_SYS_FSL_SEC_BE 550 Defines the SEC controller register space as Big Endian 551 552 CONFIG_SYS_FSL_SEC_LE 553 Defines the SEC controller register space as Little Endian 554 555- MIPS CPU options: 556 CONFIG_SYS_INIT_SP_OFFSET 557 558 Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack 559 pointer. This is needed for the temporary stack before 560 relocation. 561 562 CONFIG_SYS_MIPS_CACHE_MODE 563 564 Cache operation mode for the MIPS CPU. 565 See also arch/mips/include/asm/mipsregs.h. 566 Possible values are: 567 CONF_CM_CACHABLE_NO_WA 568 CONF_CM_CACHABLE_WA 569 CONF_CM_UNCACHED 570 CONF_CM_CACHABLE_NONCOHERENT 571 CONF_CM_CACHABLE_CE 572 CONF_CM_CACHABLE_COW 573 CONF_CM_CACHABLE_CUW 574 CONF_CM_CACHABLE_ACCELERATED 575 576 CONFIG_SYS_XWAY_EBU_BOOTCFG 577 578 Special option for Lantiq XWAY SoCs for booting from NOR flash. 579 See also arch/mips/cpu/mips32/start.S. 580 581 CONFIG_XWAY_SWAP_BYTES 582 583 Enable compilation of tools/xway-swap-bytes needed for Lantiq 584 XWAY SoCs for booting from NOR flash. The U-Boot image needs to 585 be swapped if a flash programmer is used. 586 587- ARM options: 588 CONFIG_SYS_EXCEPTION_VECTORS_HIGH 589 590 Select high exception vectors of the ARM core, e.g., do not 591 clear the V bit of the c1 register of CP15. 592 593 COUNTER_FREQUENCY 594 Generic timer clock source frequency. 595 596 COUNTER_FREQUENCY_REAL 597 Generic timer clock source frequency if the real clock is 598 different from COUNTER_FREQUENCY, and can only be determined 599 at run time. 600 601- Tegra SoC options: 602 CONFIG_TEGRA_SUPPORT_NON_SECURE 603 604 Support executing U-Boot in non-secure (NS) mode. Certain 605 impossible actions will be skipped if the CPU is in NS mode, 606 such as ARM architectural timer initialization. 607 608- Linux Kernel Interface: 609 CONFIG_CLOCKS_IN_MHZ 610 611 U-Boot stores all clock information in Hz 612 internally. For binary compatibility with older Linux 613 kernels (which expect the clocks passed in the 614 bd_info data to be in MHz) the environment variable 615 "clocks_in_mhz" can be defined so that U-Boot 616 converts clock data to MHZ before passing it to the 617 Linux kernel. 618 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of 619 "clocks_in_mhz=1" is automatically included in the 620 default environment. 621 622 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only] 623 624 When transferring memsize parameter to Linux, some versions 625 expect it to be in bytes, others in MB. 626 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes. 627 628 CONFIG_OF_LIBFDT 629 630 New kernel versions are expecting firmware settings to be 631 passed using flattened device trees (based on open firmware 632 concepts). 633 634 CONFIG_OF_LIBFDT 635 * New libfdt-based support 636 * Adds the "fdt" command 637 * The bootm command automatically updates the fdt 638 639 OF_CPU - The proper name of the cpus node (only required for 640 MPC512X and MPC5xxx based boards). 641 OF_SOC - The proper name of the soc node (only required for 642 MPC512X and MPC5xxx based boards). 643 OF_TBCLK - The timebase frequency. 644 OF_STDOUT_PATH - The path to the console device 645 646 boards with QUICC Engines require OF_QE to set UCC MAC 647 addresses 648 649 CONFIG_OF_BOARD_SETUP 650 651 Board code has addition modification that it wants to make 652 to the flat device tree before handing it off to the kernel 653 654 CONFIG_OF_SYSTEM_SETUP 655 656 Other code has addition modification that it wants to make 657 to the flat device tree before handing it off to the kernel. 658 This causes ft_system_setup() to be called before booting 659 the kernel. 660 661 CONFIG_OF_IDE_FIXUP 662 663 U-Boot can detect if an IDE device is present or not. 664 If not, and this new config option is activated, U-Boot 665 removes the ATA node from the DTS before booting Linux, 666 so the Linux IDE driver does not probe the device and 667 crash. This is needed for buggy hardware (uc101) where 668 no pull down resistor is connected to the signal IDE5V_DD7. 669 670 CONFIG_MACH_TYPE [relevant for ARM only][mandatory] 671 672 This setting is mandatory for all boards that have only one 673 machine type and must be used to specify the machine type 674 number as it appears in the ARM machine registry 675 (see http://www.arm.linux.org.uk/developer/machines/). 676 Only boards that have multiple machine types supported 677 in a single configuration file and the machine type is 678 runtime discoverable, do not have to use this setting. 679 680- vxWorks boot parameters: 681 682 bootvx constructs a valid bootline using the following 683 environments variables: bootdev, bootfile, ipaddr, netmask, 684 serverip, gatewayip, hostname, othbootargs. 685 It loads the vxWorks image pointed bootfile. 686 687 Note: If a "bootargs" environment is defined, it will overwride 688 the defaults discussed just above. 689 690- Cache Configuration: 691 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot 692 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot 693 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot 694 695- Cache Configuration for ARM: 696 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache 697 controller 698 CONFIG_SYS_PL310_BASE - Physical base address of PL310 699 controller register space 700 701- Serial Ports: 702 CONFIG_PL010_SERIAL 703 704 Define this if you want support for Amba PrimeCell PL010 UARTs. 705 706 CONFIG_PL011_SERIAL 707 708 Define this if you want support for Amba PrimeCell PL011 UARTs. 709 710 CONFIG_PL011_CLOCK 711 712 If you have Amba PrimeCell PL011 UARTs, set this variable to 713 the clock speed of the UARTs. 714 715 CONFIG_PL01x_PORTS 716 717 If you have Amba PrimeCell PL010 or PL011 UARTs on your board, 718 define this to a list of base addresses for each (supported) 719 port. See e.g. include/configs/versatile.h 720 721 CONFIG_SERIAL_HW_FLOW_CONTROL 722 723 Define this variable to enable hw flow control in serial driver. 724 Current user of this option is drivers/serial/nsl16550.c driver 725 726- Console Interface: 727 Depending on board, define exactly one serial port 728 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2, 729 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial 730 console by defining CONFIG_8xx_CONS_NONE 731 732 Note: if CONFIG_8xx_CONS_NONE is defined, the serial 733 port routines must be defined elsewhere 734 (i.e. serial_init(), serial_getc(), ...) 735 736- Console Baudrate: 737 CONFIG_BAUDRATE - in bps 738 Select one of the baudrates listed in 739 CONFIG_SYS_BAUDRATE_TABLE, see below. 740 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale 741 742- Console Rx buffer length 743 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define 744 the maximum receive buffer length for the SMC. 745 This option is actual only for 82xx and 8xx possible. 746 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE 747 must be defined, to setup the maximum idle timeout for 748 the SMC. 749 750- Autoboot Command: 751 CONFIG_BOOTCOMMAND 752 Only needed when CONFIG_BOOTDELAY is enabled; 753 define a command string that is automatically executed 754 when no character is read on the console interface 755 within "Boot Delay" after reset. 756 757 CONFIG_BOOTARGS 758 This can be used to pass arguments to the bootm 759 command. The value of CONFIG_BOOTARGS goes into the 760 environment value "bootargs". 761 762 CONFIG_RAMBOOT and CONFIG_NFSBOOT 763 The value of these goes into the environment as 764 "ramboot" and "nfsboot" respectively, and can be used 765 as a convenience, when switching between booting from 766 RAM and NFS. 767 768- Bootcount: 769 CONFIG_BOOTCOUNT_LIMIT 770 Implements a mechanism for detecting a repeating reboot 771 cycle, see: 772 http://www.denx.de/wiki/view/DULG/UBootBootCountLimit 773 774 CONFIG_BOOTCOUNT_ENV 775 If no softreset save registers are found on the hardware 776 "bootcount" is stored in the environment. To prevent a 777 saveenv on all reboots, the environment variable 778 "upgrade_available" is used. If "upgrade_available" is 779 0, "bootcount" is always 0, if "upgrade_available" is 780 1 "bootcount" is incremented in the environment. 781 So the Userspace Applikation must set the "upgrade_available" 782 and "bootcount" variable to 0, if a boot was successfully. 783 784- Pre-Boot Commands: 785 CONFIG_PREBOOT 786 787 When this option is #defined, the existence of the 788 environment variable "preboot" will be checked 789 immediately before starting the CONFIG_BOOTDELAY 790 countdown and/or running the auto-boot command resp. 791 entering interactive mode. 792 793 This feature is especially useful when "preboot" is 794 automatically generated or modified. For an example 795 see the LWMON board specific code: here "preboot" is 796 modified when the user holds down a certain 797 combination of keys on the (special) keyboard when 798 booting the systems 799 800- Serial Download Echo Mode: 801 CONFIG_LOADS_ECHO 802 If defined to 1, all characters received during a 803 serial download (using the "loads" command) are 804 echoed back. This might be needed by some terminal 805 emulations (like "cu"), but may as well just take 806 time on others. This setting #define's the initial 807 value of the "loads_echo" environment variable. 808 809- Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined) 810 CONFIG_KGDB_BAUDRATE 811 Select one of the baudrates listed in 812 CONFIG_SYS_BAUDRATE_TABLE, see below. 813 814- Monitor Functions: 815 Monitor commands can be included or excluded 816 from the build by using the #include files 817 <config_cmd_all.h> and #undef'ing unwanted 818 commands, or adding #define's for wanted commands. 819 820 The default command configuration includes all commands 821 except those marked below with a "*". 822 823 CONFIG_CMD_AES AES 128 CBC encrypt/decrypt 824 CONFIG_CMD_ASKENV * ask for env variable 825 CONFIG_CMD_BDI bdinfo 826 CONFIG_CMD_BEDBUG * Include BedBug Debugger 827 CONFIG_CMD_BMP * BMP support 828 CONFIG_CMD_BSP * Board specific commands 829 CONFIG_CMD_BOOTD bootd 830 CONFIG_CMD_BOOTI * ARM64 Linux kernel Image support 831 CONFIG_CMD_CACHE * icache, dcache 832 CONFIG_CMD_CLK * clock command support 833 CONFIG_CMD_CONSOLE coninfo 834 CONFIG_CMD_CRC32 * crc32 835 CONFIG_CMD_DATE * support for RTC, date/time... 836 CONFIG_CMD_DHCP * DHCP support 837 CONFIG_CMD_DIAG * Diagnostics 838 CONFIG_CMD_DS4510 * ds4510 I2C gpio commands 839 CONFIG_CMD_DS4510_INFO * ds4510 I2C info command 840 CONFIG_CMD_DS4510_MEM * ds4510 I2C eeprom/sram commansd 841 CONFIG_CMD_DS4510_RST * ds4510 I2C rst command 842 CONFIG_CMD_DTT * Digital Therm and Thermostat 843 CONFIG_CMD_ECHO echo arguments 844 CONFIG_CMD_EDITENV edit env variable 845 CONFIG_CMD_EEPROM * EEPROM read/write support 846 CONFIG_CMD_EEPROM_LAYOUT* EEPROM layout aware commands 847 CONFIG_CMD_ELF * bootelf, bootvx 848 CONFIG_CMD_ENV_CALLBACK * display details about env callbacks 849 CONFIG_CMD_ENV_FLAGS * display details about env flags 850 CONFIG_CMD_ENV_EXISTS * check existence of env variable 851 CONFIG_CMD_EXPORTENV * export the environment 852 CONFIG_CMD_EXT2 * ext2 command support 853 CONFIG_CMD_EXT4 * ext4 command support 854 CONFIG_CMD_FS_GENERIC * filesystem commands (e.g. load, ls) 855 that work for multiple fs types 856 CONFIG_CMD_FS_UUID * Look up a filesystem UUID 857 CONFIG_CMD_SAVEENV saveenv 858 CONFIG_CMD_FDC * Floppy Disk Support 859 CONFIG_CMD_FAT * FAT command support 860 CONFIG_CMD_FLASH flinfo, erase, protect 861 CONFIG_CMD_FPGA FPGA device initialization support 862 CONFIG_CMD_FUSE * Device fuse support 863 CONFIG_CMD_GETTIME * Get time since boot 864 CONFIG_CMD_GO * the 'go' command (exec code) 865 CONFIG_CMD_GREPENV * search environment 866 CONFIG_CMD_HASH * calculate hash / digest 867 CONFIG_CMD_I2C * I2C serial bus support 868 CONFIG_CMD_IDE * IDE harddisk support 869 CONFIG_CMD_IMI iminfo 870 CONFIG_CMD_IMLS List all images found in NOR flash 871 CONFIG_CMD_IMLS_NAND * List all images found in NAND flash 872 CONFIG_CMD_IMMAP * IMMR dump support 873 CONFIG_CMD_IOTRACE * I/O tracing for debugging 874 CONFIG_CMD_IMPORTENV * import an environment 875 CONFIG_CMD_INI * import data from an ini file into the env 876 CONFIG_CMD_IRQ * irqinfo 877 CONFIG_CMD_ITEST Integer/string test of 2 values 878 CONFIG_CMD_JFFS2 * JFFS2 Support 879 CONFIG_CMD_KGDB * kgdb 880 CONFIG_CMD_LDRINFO * ldrinfo (display Blackfin loader) 881 CONFIG_CMD_LINK_LOCAL * link-local IP address auto-configuration 882 (169.254.*.*) 883 CONFIG_CMD_LOADB loadb 884 CONFIG_CMD_LOADS loads 885 CONFIG_CMD_MD5SUM * print md5 message digest 886 (requires CONFIG_CMD_MEMORY and CONFIG_MD5) 887 CONFIG_CMD_MEMINFO * Display detailed memory information 888 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base, 889 loop, loopw 890 CONFIG_CMD_MEMTEST * mtest 891 CONFIG_CMD_MISC Misc functions like sleep etc 892 CONFIG_CMD_MMC * MMC memory mapped support 893 CONFIG_CMD_MII * MII utility commands 894 CONFIG_CMD_MTDPARTS * MTD partition support 895 CONFIG_CMD_NAND * NAND support 896 CONFIG_CMD_NET bootp, tftpboot, rarpboot 897 CONFIG_CMD_NFS NFS support 898 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands 899 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command 900 CONFIG_CMD_PCI * pciinfo 901 CONFIG_CMD_PCMCIA * PCMCIA support 902 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network 903 host 904 CONFIG_CMD_PORTIO * Port I/O 905 CONFIG_CMD_READ * Read raw data from partition 906 CONFIG_CMD_REGINFO * Register dump 907 CONFIG_CMD_RUN run command in env variable 908 CONFIG_CMD_SANDBOX * sb command to access sandbox features 909 CONFIG_CMD_SAVES * save S record dump 910 CONFIG_SCSI * SCSI Support 911 CONFIG_CMD_SDRAM * print SDRAM configuration information 912 (requires CONFIG_CMD_I2C) 913 CONFIG_CMD_SETGETDCR Support for DCR Register access 914 (4xx only) 915 CONFIG_CMD_SF * Read/write/erase SPI NOR flash 916 CONFIG_CMD_SHA1SUM * print sha1 memory digest 917 (requires CONFIG_CMD_MEMORY) 918 CONFIG_CMD_SOFTSWITCH * Soft switch setting command for BF60x 919 CONFIG_CMD_SOURCE "source" command Support 920 CONFIG_CMD_SPI * SPI serial bus support 921 CONFIG_CMD_TFTPSRV * TFTP transfer in server mode 922 CONFIG_CMD_TFTPPUT * TFTP put command (upload) 923 CONFIG_CMD_TIME * run command and report execution time (ARM specific) 924 CONFIG_CMD_TIMER * access to the system tick timer 925 CONFIG_CMD_USB * USB support 926 CONFIG_CMD_CDP * Cisco Discover Protocol support 927 CONFIG_CMD_MFSL * Microblaze FSL support 928 CONFIG_CMD_XIMG Load part of Multi Image 929 CONFIG_CMD_UUID * Generate random UUID or GUID string 930 931 EXAMPLE: If you want all functions except of network 932 support you can write: 933 934 #include "config_cmd_all.h" 935 #undef CONFIG_CMD_NET 936 937 Other Commands: 938 fdt (flattened device tree) command: CONFIG_OF_LIBFDT 939 940 Note: Don't enable the "icache" and "dcache" commands 941 (configuration option CONFIG_CMD_CACHE) unless you know 942 what you (and your U-Boot users) are doing. Data 943 cache cannot be enabled on systems like the 8xx or 944 8260 (where accesses to the IMMR region must be 945 uncached), and it cannot be disabled on all other 946 systems where we (mis-) use the data cache to hold an 947 initial stack and some data. 948 949 950 XXX - this list needs to get updated! 951 952- Removal of commands 953 If no commands are needed to boot, you can disable 954 CONFIG_CMDLINE to remove them. In this case, the command line 955 will not be available, and when U-Boot wants to execute the 956 boot command (on start-up) it will call board_run_command() 957 instead. This can reduce image size significantly for very 958 simple boot procedures. 959 960- Regular expression support: 961 CONFIG_REGEX 962 If this variable is defined, U-Boot is linked against 963 the SLRE (Super Light Regular Expression) library, 964 which adds regex support to some commands, as for 965 example "env grep" and "setexpr". 966 967- Device tree: 968 CONFIG_OF_CONTROL 969 If this variable is defined, U-Boot will use a device tree 970 to configure its devices, instead of relying on statically 971 compiled #defines in the board file. This option is 972 experimental and only available on a few boards. The device 973 tree is available in the global data as gd->fdt_blob. 974 975 U-Boot needs to get its device tree from somewhere. This can 976 be done using one of the two options below: 977 978 CONFIG_OF_EMBED 979 If this variable is defined, U-Boot will embed a device tree 980 binary in its image. This device tree file should be in the 981 board directory and called <soc>-<board>.dts. The binary file 982 is then picked up in board_init_f() and made available through 983 the global data structure as gd->blob. 984 985 CONFIG_OF_SEPARATE 986 If this variable is defined, U-Boot will build a device tree 987 binary. It will be called u-boot.dtb. Architecture-specific 988 code will locate it at run-time. Generally this works by: 989 990 cat u-boot.bin u-boot.dtb >image.bin 991 992 and in fact, U-Boot does this for you, creating a file called 993 u-boot-dtb.bin which is useful in the common case. You can 994 still use the individual files if you need something more 995 exotic. 996 997- Watchdog: 998 CONFIG_WATCHDOG 999 If this variable is defined, it enables watchdog 1000 support for the SoC. There must be support in the SoC 1001 specific code for a watchdog. For the 8xx and 8260 1002 CPUs, the SIU Watchdog feature is enabled in the SYPCR 1003 register. When supported for a specific SoC is 1004 available, then no further board specific code should 1005 be needed to use it. 1006 1007 CONFIG_HW_WATCHDOG 1008 When using a watchdog circuitry external to the used 1009 SoC, then define this variable and provide board 1010 specific code for the "hw_watchdog_reset" function. 1011 1012 CONFIG_AT91_HW_WDT_TIMEOUT 1013 specify the timeout in seconds. default 2 seconds. 1014 1015- U-Boot Version: 1016 CONFIG_VERSION_VARIABLE 1017 If this variable is defined, an environment variable 1018 named "ver" is created by U-Boot showing the U-Boot 1019 version as printed by the "version" command. 1020 Any change to this variable will be reverted at the 1021 next reset. 1022 1023- Real-Time Clock: 1024 1025 When CONFIG_CMD_DATE is selected, the type of the RTC 1026 has to be selected, too. Define exactly one of the 1027 following options: 1028 1029 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx 1030 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC 1031 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC 1032 CONFIG_RTC_MC146818 - use MC146818 RTC 1033 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC 1034 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC 1035 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC 1036 CONFIG_RTC_DS1339 - use Maxim, Inc. DS1339 RTC 1037 CONFIG_RTC_DS164x - use Dallas DS164x RTC 1038 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC 1039 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC 1040 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337 1041 CONFIG_SYS_RV3029_TCR - enable trickle charger on 1042 RV3029 RTC. 1043 1044 Note that if the RTC uses I2C, then the I2C interface 1045 must also be configured. See I2C Support, below. 1046 1047- GPIO Support: 1048 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO 1049 1050 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of 1051 chip-ngpio pairs that tell the PCA953X driver the number of 1052 pins supported by a particular chip. 1053 1054 Note that if the GPIO device uses I2C, then the I2C interface 1055 must also be configured. See I2C Support, below. 1056 1057- I/O tracing: 1058 When CONFIG_IO_TRACE is selected, U-Boot intercepts all I/O 1059 accesses and can checksum them or write a list of them out 1060 to memory. See the 'iotrace' command for details. This is 1061 useful for testing device drivers since it can confirm that 1062 the driver behaves the same way before and after a code 1063 change. Currently this is supported on sandbox and arm. To 1064 add support for your architecture, add '#include <iotrace.h>' 1065 to the bottom of arch/<arch>/include/asm/io.h and test. 1066 1067 Example output from the 'iotrace stats' command is below. 1068 Note that if the trace buffer is exhausted, the checksum will 1069 still continue to operate. 1070 1071 iotrace is enabled 1072 Start: 10000000 (buffer start address) 1073 Size: 00010000 (buffer size) 1074 Offset: 00000120 (current buffer offset) 1075 Output: 10000120 (start + offset) 1076 Count: 00000018 (number of trace records) 1077 CRC32: 9526fb66 (CRC32 of all trace records) 1078 1079- Timestamp Support: 1080 1081 When CONFIG_TIMESTAMP is selected, the timestamp 1082 (date and time) of an image is printed by image 1083 commands like bootm or iminfo. This option is 1084 automatically enabled when you select CONFIG_CMD_DATE . 1085 1086- Partition Labels (disklabels) Supported: 1087 Zero or more of the following: 1088 CONFIG_MAC_PARTITION Apple's MacOS partition table. 1089 CONFIG_DOS_PARTITION MS Dos partition table, traditional on the 1090 Intel architecture, USB sticks, etc. 1091 CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc. 1092 CONFIG_EFI_PARTITION GPT partition table, common when EFI is the 1093 bootloader. Note 2TB partition limit; see 1094 disk/part_efi.c 1095 CONFIG_MTD_PARTITIONS Memory Technology Device partition table. 1096 1097 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or 1098 CONFIG_SCSI) you must configure support for at 1099 least one non-MTD partition type as well. 1100 1101- IDE Reset method: 1102 CONFIG_IDE_RESET_ROUTINE - this is defined in several 1103 board configurations files but used nowhere! 1104 1105 CONFIG_IDE_RESET - is this is defined, IDE Reset will 1106 be performed by calling the function 1107 ide_set_reset(int reset) 1108 which has to be defined in a board specific file 1109 1110- ATAPI Support: 1111 CONFIG_ATAPI 1112 1113 Set this to enable ATAPI support. 1114 1115- LBA48 Support 1116 CONFIG_LBA48 1117 1118 Set this to enable support for disks larger than 137GB 1119 Also look at CONFIG_SYS_64BIT_LBA. 1120 Whithout these , LBA48 support uses 32bit variables and will 'only' 1121 support disks up to 2.1TB. 1122 1123 CONFIG_SYS_64BIT_LBA: 1124 When enabled, makes the IDE subsystem use 64bit sector addresses. 1125 Default is 32bit. 1126 1127- SCSI Support: 1128 At the moment only there is only support for the 1129 SYM53C8XX SCSI controller; define 1130 CONFIG_SCSI_SYM53C8XX to enable it. 1131 1132 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and 1133 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID * 1134 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the 1135 maximum numbers of LUNs, SCSI ID's and target 1136 devices. 1137 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz) 1138 1139 The environment variable 'scsidevs' is set to the number of 1140 SCSI devices found during the last scan. 1141 1142- NETWORK Support (PCI): 1143 CONFIG_E1000 1144 Support for Intel 8254x/8257x gigabit chips. 1145 1146 CONFIG_E1000_SPI 1147 Utility code for direct access to the SPI bus on Intel 8257x. 1148 This does not do anything useful unless you set at least one 1149 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC. 1150 1151 CONFIG_E1000_SPI_GENERIC 1152 Allow generic access to the SPI bus on the Intel 8257x, for 1153 example with the "sspi" command. 1154 1155 CONFIG_CMD_E1000 1156 Management command for E1000 devices. When used on devices 1157 with SPI support you can reprogram the EEPROM from U-Boot. 1158 1159 CONFIG_EEPRO100 1160 Support for Intel 82557/82559/82559ER chips. 1161 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM 1162 write routine for first time initialisation. 1163 1164 CONFIG_TULIP 1165 Support for Digital 2114x chips. 1166 Optional CONFIG_TULIP_SELECT_MEDIA for board specific 1167 modem chip initialisation (KS8761/QS6611). 1168 1169 CONFIG_NATSEMI 1170 Support for National dp83815 chips. 1171 1172 CONFIG_NS8382X 1173 Support for National dp8382[01] gigabit chips. 1174 1175- NETWORK Support (other): 1176 1177 CONFIG_DRIVER_AT91EMAC 1178 Support for AT91RM9200 EMAC. 1179 1180 CONFIG_RMII 1181 Define this to use reduced MII inteface 1182 1183 CONFIG_DRIVER_AT91EMAC_QUIET 1184 If this defined, the driver is quiet. 1185 The driver doen't show link status messages. 1186 1187 CONFIG_CALXEDA_XGMAC 1188 Support for the Calxeda XGMAC device 1189 1190 CONFIG_LAN91C96 1191 Support for SMSC's LAN91C96 chips. 1192 1193 CONFIG_LAN91C96_USE_32_BIT 1194 Define this to enable 32 bit addressing 1195 1196 CONFIG_SMC91111 1197 Support for SMSC's LAN91C111 chip 1198 1199 CONFIG_SMC91111_BASE 1200 Define this to hold the physical address 1201 of the device (I/O space) 1202 1203 CONFIG_SMC_USE_32_BIT 1204 Define this if data bus is 32 bits 1205 1206 CONFIG_SMC_USE_IOFUNCS 1207 Define this to use i/o functions instead of macros 1208 (some hardware wont work with macros) 1209 1210 CONFIG_DRIVER_TI_EMAC 1211 Support for davinci emac 1212 1213 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT 1214 Define this if you have more then 3 PHYs. 1215 1216 CONFIG_FTGMAC100 1217 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet 1218 1219 CONFIG_FTGMAC100_EGIGA 1220 Define this to use GE link update with gigabit PHY. 1221 Define this if FTGMAC100 is connected to gigabit PHY. 1222 If your system has 10/100 PHY only, it might not occur 1223 wrong behavior. Because PHY usually return timeout or 1224 useless data when polling gigabit status and gigabit 1225 control registers. This behavior won't affect the 1226 correctnessof 10/100 link speed update. 1227 1228 CONFIG_SMC911X 1229 Support for SMSC's LAN911x and LAN921x chips 1230 1231 CONFIG_SMC911X_BASE 1232 Define this to hold the physical address 1233 of the device (I/O space) 1234 1235 CONFIG_SMC911X_32_BIT 1236 Define this if data bus is 32 bits 1237 1238 CONFIG_SMC911X_16_BIT 1239 Define this if data bus is 16 bits. If your processor 1240 automatically converts one 32 bit word to two 16 bit 1241 words you may also try CONFIG_SMC911X_32_BIT. 1242 1243 CONFIG_SH_ETHER 1244 Support for Renesas on-chip Ethernet controller 1245 1246 CONFIG_SH_ETHER_USE_PORT 1247 Define the number of ports to be used 1248 1249 CONFIG_SH_ETHER_PHY_ADDR 1250 Define the ETH PHY's address 1251 1252 CONFIG_SH_ETHER_CACHE_WRITEBACK 1253 If this option is set, the driver enables cache flush. 1254 1255- PWM Support: 1256 CONFIG_PWM_IMX 1257 Support for PWM module on the imx6. 1258 1259- TPM Support: 1260 CONFIG_TPM 1261 Support TPM devices. 1262 1263 CONFIG_TPM_TIS_INFINEON 1264 Support for Infineon i2c bus TPM devices. Only one device 1265 per system is supported at this time. 1266 1267 CONFIG_TPM_TIS_I2C_BURST_LIMITATION 1268 Define the burst count bytes upper limit 1269 1270 CONFIG_TPM_ST33ZP24 1271 Support for STMicroelectronics TPM devices. Requires DM_TPM support. 1272 1273 CONFIG_TPM_ST33ZP24_I2C 1274 Support for STMicroelectronics ST33ZP24 I2C devices. 1275 Requires TPM_ST33ZP24 and I2C. 1276 1277 CONFIG_TPM_ST33ZP24_SPI 1278 Support for STMicroelectronics ST33ZP24 SPI devices. 1279 Requires TPM_ST33ZP24 and SPI. 1280 1281 CONFIG_TPM_ATMEL_TWI 1282 Support for Atmel TWI TPM device. Requires I2C support. 1283 1284 CONFIG_TPM_TIS_LPC 1285 Support for generic parallel port TPM devices. Only one device 1286 per system is supported at this time. 1287 1288 CONFIG_TPM_TIS_BASE_ADDRESS 1289 Base address where the generic TPM device is mapped 1290 to. Contemporary x86 systems usually map it at 1291 0xfed40000. 1292 1293 CONFIG_CMD_TPM 1294 Add tpm monitor functions. 1295 Requires CONFIG_TPM. If CONFIG_TPM_AUTH_SESSIONS is set, also 1296 provides monitor access to authorized functions. 1297 1298 CONFIG_TPM 1299 Define this to enable the TPM support library which provides 1300 functional interfaces to some TPM commands. 1301 Requires support for a TPM device. 1302 1303 CONFIG_TPM_AUTH_SESSIONS 1304 Define this to enable authorized functions in the TPM library. 1305 Requires CONFIG_TPM and CONFIG_SHA1. 1306 1307- USB Support: 1308 At the moment only the UHCI host controller is 1309 supported (PIP405, MIP405, MPC5200); define 1310 CONFIG_USB_UHCI to enable it. 1311 define CONFIG_USB_KEYBOARD to enable the USB Keyboard 1312 and define CONFIG_USB_STORAGE to enable the USB 1313 storage devices. 1314 Note: 1315 Supported are USB Keyboards and USB Floppy drives 1316 (TEAC FD-05PUB). 1317 MPC5200 USB requires additional defines: 1318 CONFIG_USB_CLOCK 1319 for 528 MHz Clock: 0x0001bbbb 1320 CONFIG_PSC3_USB 1321 for USB on PSC3 1322 CONFIG_USB_CONFIG 1323 for differential drivers: 0x00001000 1324 for single ended drivers: 0x00005000 1325 for differential drivers on PSC3: 0x00000100 1326 for single ended drivers on PSC3: 0x00004100 1327 CONFIG_SYS_USB_EVENT_POLL 1328 May be defined to allow interrupt polling 1329 instead of using asynchronous interrupts 1330 1331 CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the 1332 txfilltuning field in the EHCI controller on reset. 1333 1334 CONFIG_USB_DWC2_REG_ADDR the physical CPU address of the DWC2 1335 HW module registers. 1336 1337- USB Device: 1338 Define the below if you wish to use the USB console. 1339 Once firmware is rebuilt from a serial console issue the 1340 command "setenv stdin usbtty; setenv stdout usbtty" and 1341 attach your USB cable. The Unix command "dmesg" should print 1342 it has found a new device. The environment variable usbtty 1343 can be set to gserial or cdc_acm to enable your device to 1344 appear to a USB host as a Linux gserial device or a 1345 Common Device Class Abstract Control Model serial device. 1346 If you select usbtty = gserial you should be able to enumerate 1347 a Linux host by 1348 # modprobe usbserial vendor=0xVendorID product=0xProductID 1349 else if using cdc_acm, simply setting the environment 1350 variable usbtty to be cdc_acm should suffice. The following 1351 might be defined in YourBoardName.h 1352 1353 CONFIG_USB_DEVICE 1354 Define this to build a UDC device 1355 1356 CONFIG_USB_TTY 1357 Define this to have a tty type of device available to 1358 talk to the UDC device 1359 1360 CONFIG_USBD_HS 1361 Define this to enable the high speed support for usb 1362 device and usbtty. If this feature is enabled, a routine 1363 int is_usbd_high_speed(void) 1364 also needs to be defined by the driver to dynamically poll 1365 whether the enumeration has succeded at high speed or full 1366 speed. 1367 1368 CONFIG_SYS_CONSOLE_IS_IN_ENV 1369 Define this if you want stdin, stdout &/or stderr to 1370 be set to usbtty. 1371 1372 mpc8xx: 1373 CONFIG_SYS_USB_EXTC_CLK 0xBLAH 1374 Derive USB clock from external clock "blah" 1375 - CONFIG_SYS_USB_EXTC_CLK 0x02 1376 1377 If you have a USB-IF assigned VendorID then you may wish to 1378 define your own vendor specific values either in BoardName.h 1379 or directly in usbd_vendor_info.h. If you don't define 1380 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME, 1381 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot 1382 should pretend to be a Linux device to it's target host. 1383 1384 CONFIG_USBD_MANUFACTURER 1385 Define this string as the name of your company for 1386 - CONFIG_USBD_MANUFACTURER "my company" 1387 1388 CONFIG_USBD_PRODUCT_NAME 1389 Define this string as the name of your product 1390 - CONFIG_USBD_PRODUCT_NAME "acme usb device" 1391 1392 CONFIG_USBD_VENDORID 1393 Define this as your assigned Vendor ID from the USB 1394 Implementors Forum. This *must* be a genuine Vendor ID 1395 to avoid polluting the USB namespace. 1396 - CONFIG_USBD_VENDORID 0xFFFF 1397 1398 CONFIG_USBD_PRODUCTID 1399 Define this as the unique Product ID 1400 for your device 1401 - CONFIG_USBD_PRODUCTID 0xFFFF 1402 1403- ULPI Layer Support: 1404 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via 1405 the generic ULPI layer. The generic layer accesses the ULPI PHY 1406 via the platform viewport, so you need both the genric layer and 1407 the viewport enabled. Currently only Chipidea/ARC based 1408 viewport is supported. 1409 To enable the ULPI layer support, define CONFIG_USB_ULPI and 1410 CONFIG_USB_ULPI_VIEWPORT in your board configuration file. 1411 If your ULPI phy needs a different reference clock than the 1412 standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to 1413 the appropriate value in Hz. 1414 1415- MMC Support: 1416 The MMC controller on the Intel PXA is supported. To 1417 enable this define CONFIG_MMC. The MMC can be 1418 accessed from the boot prompt by mapping the device 1419 to physical memory similar to flash. Command line is 1420 enabled with CONFIG_CMD_MMC. The MMC driver also works with 1421 the FAT fs. This is enabled with CONFIG_CMD_FAT. 1422 1423 CONFIG_SH_MMCIF 1424 Support for Renesas on-chip MMCIF controller 1425 1426 CONFIG_SH_MMCIF_ADDR 1427 Define the base address of MMCIF registers 1428 1429 CONFIG_SH_MMCIF_CLK 1430 Define the clock frequency for MMCIF 1431 1432 CONFIG_SUPPORT_EMMC_BOOT 1433 Enable some additional features of the eMMC boot partitions. 1434 1435 CONFIG_SUPPORT_EMMC_RPMB 1436 Enable the commands for reading, writing and programming the 1437 key for the Replay Protection Memory Block partition in eMMC. 1438 1439- USB Device Firmware Update (DFU) class support: 1440 CONFIG_USB_FUNCTION_DFU 1441 This enables the USB portion of the DFU USB class 1442 1443 CONFIG_CMD_DFU 1444 This enables the command "dfu" which is used to have 1445 U-Boot create a DFU class device via USB. This command 1446 requires that the "dfu_alt_info" environment variable be 1447 set and define the alt settings to expose to the host. 1448 1449 CONFIG_DFU_MMC 1450 This enables support for exposing (e)MMC devices via DFU. 1451 1452 CONFIG_DFU_NAND 1453 This enables support for exposing NAND devices via DFU. 1454 1455 CONFIG_DFU_RAM 1456 This enables support for exposing RAM via DFU. 1457 Note: DFU spec refer to non-volatile memory usage, but 1458 allow usages beyond the scope of spec - here RAM usage, 1459 one that would help mostly the developer. 1460 1461 CONFIG_SYS_DFU_DATA_BUF_SIZE 1462 Dfu transfer uses a buffer before writing data to the 1463 raw storage device. Make the size (in bytes) of this buffer 1464 configurable. The size of this buffer is also configurable 1465 through the "dfu_bufsiz" environment variable. 1466 1467 CONFIG_SYS_DFU_MAX_FILE_SIZE 1468 When updating files rather than the raw storage device, 1469 we use a static buffer to copy the file into and then write 1470 the buffer once we've been given the whole file. Define 1471 this to the maximum filesize (in bytes) for the buffer. 1472 Default is 4 MiB if undefined. 1473 1474 DFU_DEFAULT_POLL_TIMEOUT 1475 Poll timeout [ms], is the timeout a device can send to the 1476 host. The host must wait for this timeout before sending 1477 a subsequent DFU_GET_STATUS request to the device. 1478 1479 DFU_MANIFEST_POLL_TIMEOUT 1480 Poll timeout [ms], which the device sends to the host when 1481 entering dfuMANIFEST state. Host waits this timeout, before 1482 sending again an USB request to the device. 1483 1484- USB Device Android Fastboot support: 1485 CONFIG_USB_FUNCTION_FASTBOOT 1486 This enables the USB part of the fastboot gadget 1487 1488 CONFIG_CMD_FASTBOOT 1489 This enables the command "fastboot" which enables the Android 1490 fastboot mode for the platform's USB device. Fastboot is a USB 1491 protocol for downloading images, flashing and device control 1492 used on Android devices. 1493 See doc/README.android-fastboot for more information. 1494 1495 CONFIG_ANDROID_BOOT_IMAGE 1496 This enables support for booting images which use the Android 1497 image format header. 1498 1499 CONFIG_FASTBOOT_BUF_ADDR 1500 The fastboot protocol requires a large memory buffer for 1501 downloads. Define this to the starting RAM address to use for 1502 downloaded images. 1503 1504 CONFIG_FASTBOOT_BUF_SIZE 1505 The fastboot protocol requires a large memory buffer for 1506 downloads. This buffer should be as large as possible for a 1507 platform. Define this to the size available RAM for fastboot. 1508 1509 CONFIG_FASTBOOT_FLASH 1510 The fastboot protocol includes a "flash" command for writing 1511 the downloaded image to a non-volatile storage device. Define 1512 this to enable the "fastboot flash" command. 1513 1514 CONFIG_FASTBOOT_FLASH_MMC_DEV 1515 The fastboot "flash" command requires additional information 1516 regarding the non-volatile storage device. Define this to 1517 the eMMC device that fastboot should use to store the image. 1518 1519 CONFIG_FASTBOOT_GPT_NAME 1520 The fastboot "flash" command supports writing the downloaded 1521 image to the Protective MBR and the Primary GUID Partition 1522 Table. (Additionally, this downloaded image is post-processed 1523 to generate and write the Backup GUID Partition Table.) 1524 This occurs when the specified "partition name" on the 1525 "fastboot flash" command line matches this value. 1526 The default is "gpt" if undefined. 1527 1528 CONFIG_FASTBOOT_MBR_NAME 1529 The fastboot "flash" command supports writing the downloaded 1530 image to DOS MBR. 1531 This occurs when the "partition name" specified on the 1532 "fastboot flash" command line matches this value. 1533 If not defined the default value "mbr" is used. 1534 1535- Journaling Flash filesystem support: 1536 CONFIG_JFFS2_NAND 1537 Define these for a default partition on a NAND device 1538 1539 CONFIG_SYS_JFFS2_FIRST_SECTOR, 1540 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS 1541 Define these for a default partition on a NOR device 1542 1543- FAT(File Allocation Table) filesystem write function support: 1544 CONFIG_FAT_WRITE 1545 1546 Define this to enable support for saving memory data as a 1547 file in FAT formatted partition. 1548 1549 This will also enable the command "fatwrite" enabling the 1550 user to write files to FAT. 1551 1552- CBFS (Coreboot Filesystem) support: 1553 CONFIG_CMD_CBFS 1554 1555 Define this to enable support for reading from a Coreboot 1556 filesystem. Available commands are cbfsinit, cbfsinfo, cbfsls 1557 and cbfsload. 1558 1559- FAT(File Allocation Table) filesystem cluster size: 1560 CONFIG_FS_FAT_MAX_CLUSTSIZE 1561 1562 Define the max cluster size for fat operations else 1563 a default value of 65536 will be defined. 1564 1565- Keyboard Support: 1566 See Kconfig help for available keyboard drivers. 1567 1568 CONFIG_KEYBOARD 1569 1570 Define this to enable a custom keyboard support. 1571 This simply calls drv_keyboard_init() which must be 1572 defined in your board-specific files. This option is deprecated 1573 and is only used by novena. For new boards, use driver model 1574 instead. 1575 1576- Video support: 1577 CONFIG_FSL_DIU_FB 1578 Enable the Freescale DIU video driver. Reference boards for 1579 SOCs that have a DIU should define this macro to enable DIU 1580 support, and should also define these other macros: 1581 1582 CONFIG_SYS_DIU_ADDR 1583 CONFIG_VIDEO 1584 CONFIG_CMD_BMP 1585 CONFIG_CFB_CONSOLE 1586 CONFIG_VIDEO_SW_CURSOR 1587 CONFIG_VGA_AS_SINGLE_DEVICE 1588 CONFIG_VIDEO_LOGO 1589 CONFIG_VIDEO_BMP_LOGO 1590 1591 The DIU driver will look for the 'video-mode' environment 1592 variable, and if defined, enable the DIU as a console during 1593 boot. See the documentation file doc/README.video for a 1594 description of this variable. 1595 1596- LCD Support: CONFIG_LCD 1597 1598 Define this to enable LCD support (for output to LCD 1599 display); also select one of the supported displays 1600 by defining one of these: 1601 1602 CONFIG_ATMEL_LCD: 1603 1604 HITACHI TX09D70VM1CCA, 3.5", 240x320. 1605 1606 CONFIG_NEC_NL6448AC33: 1607 1608 NEC NL6448AC33-18. Active, color, single scan. 1609 1610 CONFIG_NEC_NL6448BC20 1611 1612 NEC NL6448BC20-08. 6.5", 640x480. 1613 Active, color, single scan. 1614 1615 CONFIG_NEC_NL6448BC33_54 1616 1617 NEC NL6448BC33-54. 10.4", 640x480. 1618 Active, color, single scan. 1619 1620 CONFIG_SHARP_16x9 1621 1622 Sharp 320x240. Active, color, single scan. 1623 It isn't 16x9, and I am not sure what it is. 1624 1625 CONFIG_SHARP_LQ64D341 1626 1627 Sharp LQ64D341 display, 640x480. 1628 Active, color, single scan. 1629 1630 CONFIG_HLD1045 1631 1632 HLD1045 display, 640x480. 1633 Active, color, single scan. 1634 1635 CONFIG_OPTREX_BW 1636 1637 Optrex CBL50840-2 NF-FW 99 22 M5 1638 or 1639 Hitachi LMG6912RPFC-00T 1640 or 1641 Hitachi SP14Q002 1642 1643 320x240. Black & white. 1644 1645 Normally display is black on white background; define 1646 CONFIG_SYS_WHITE_ON_BLACK to get it inverted. 1647 1648 CONFIG_LCD_ALIGNMENT 1649 1650 Normally the LCD is page-aligned (typically 4KB). If this is 1651 defined then the LCD will be aligned to this value instead. 1652 For ARM it is sometimes useful to use MMU_SECTION_SIZE 1653 here, since it is cheaper to change data cache settings on 1654 a per-section basis. 1655 1656 1657 CONFIG_LCD_ROTATION 1658 1659 Sometimes, for example if the display is mounted in portrait 1660 mode or even if it's mounted landscape but rotated by 180degree, 1661 we need to rotate our content of the display relative to the 1662 framebuffer, so that user can read the messages which are 1663 printed out. 1664 Once CONFIG_LCD_ROTATION is defined, the lcd_console will be 1665 initialized with a given rotation from "vl_rot" out of 1666 "vidinfo_t" which is provided by the board specific code. 1667 The value for vl_rot is coded as following (matching to 1668 fbcon=rotate:<n> linux-kernel commandline): 1669 0 = no rotation respectively 0 degree 1670 1 = 90 degree rotation 1671 2 = 180 degree rotation 1672 3 = 270 degree rotation 1673 1674 If CONFIG_LCD_ROTATION is not defined, the console will be 1675 initialized with 0degree rotation. 1676 1677 CONFIG_LCD_BMP_RLE8 1678 1679 Support drawing of RLE8-compressed bitmaps on the LCD. 1680 1681 CONFIG_I2C_EDID 1682 1683 Enables an 'i2c edid' command which can read EDID 1684 information over I2C from an attached LCD display. 1685 1686- Splash Screen Support: CONFIG_SPLASH_SCREEN 1687 1688 If this option is set, the environment is checked for 1689 a variable "splashimage". If found, the usual display 1690 of logo, copyright and system information on the LCD 1691 is suppressed and the BMP image at the address 1692 specified in "splashimage" is loaded instead. The 1693 console is redirected to the "nulldev", too. This 1694 allows for a "silent" boot where a splash screen is 1695 loaded very quickly after power-on. 1696 1697 CONFIG_SPLASHIMAGE_GUARD 1698 1699 If this option is set, then U-Boot will prevent the environment 1700 variable "splashimage" from being set to a problematic address 1701 (see doc/README.displaying-bmps). 1702 This option is useful for targets where, due to alignment 1703 restrictions, an improperly aligned BMP image will cause a data 1704 abort. If you think you will not have problems with unaligned 1705 accesses (for example because your toolchain prevents them) 1706 there is no need to set this option. 1707 1708 CONFIG_SPLASH_SCREEN_ALIGN 1709 1710 If this option is set the splash image can be freely positioned 1711 on the screen. Environment variable "splashpos" specifies the 1712 position as "x,y". If a positive number is given it is used as 1713 number of pixel from left/top. If a negative number is given it 1714 is used as number of pixel from right/bottom. You can also 1715 specify 'm' for centering the image. 1716 1717 Example: 1718 setenv splashpos m,m 1719 => image at center of screen 1720 1721 setenv splashpos 30,20 1722 => image at x = 30 and y = 20 1723 1724 setenv splashpos -10,m 1725 => vertically centered image 1726 at x = dspWidth - bmpWidth - 9 1727 1728- Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP 1729 1730 If this option is set, additionally to standard BMP 1731 images, gzipped BMP images can be displayed via the 1732 splashscreen support or the bmp command. 1733 1734- Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8 1735 1736 If this option is set, 8-bit RLE compressed BMP images 1737 can be displayed via the splashscreen support or the 1738 bmp command. 1739 1740- Compression support: 1741 CONFIG_GZIP 1742 1743 Enabled by default to support gzip compressed images. 1744 1745 CONFIG_BZIP2 1746 1747 If this option is set, support for bzip2 compressed 1748 images is included. If not, only uncompressed and gzip 1749 compressed images are supported. 1750 1751 NOTE: the bzip2 algorithm requires a lot of RAM, so 1752 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should 1753 be at least 4MB. 1754 1755 CONFIG_LZMA 1756 1757 If this option is set, support for lzma compressed 1758 images is included. 1759 1760 Note: The LZMA algorithm adds between 2 and 4KB of code and it 1761 requires an amount of dynamic memory that is given by the 1762 formula: 1763 1764 (1846 + 768 << (lc + lp)) * sizeof(uint16) 1765 1766 Where lc and lp stand for, respectively, Literal context bits 1767 and Literal pos bits. 1768 1769 This value is upper-bounded by 14MB in the worst case. Anyway, 1770 for a ~4MB large kernel image, we have lc=3 and lp=0 for a 1771 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is 1772 a very small buffer. 1773 1774 Use the lzmainfo tool to determinate the lc and lp values and 1775 then calculate the amount of needed dynamic memory (ensuring 1776 the appropriate CONFIG_SYS_MALLOC_LEN value). 1777 1778 CONFIG_LZO 1779 1780 If this option is set, support for LZO compressed images 1781 is included. 1782 1783- MII/PHY support: 1784 CONFIG_PHY_ADDR 1785 1786 The address of PHY on MII bus. 1787 1788 CONFIG_PHY_CLOCK_FREQ (ppc4xx) 1789 1790 The clock frequency of the MII bus 1791 1792 CONFIG_PHY_GIGE 1793 1794 If this option is set, support for speed/duplex 1795 detection of gigabit PHY is included. 1796 1797 CONFIG_PHY_RESET_DELAY 1798 1799 Some PHY like Intel LXT971A need extra delay after 1800 reset before any MII register access is possible. 1801 For such PHY, set this option to the usec delay 1802 required. (minimum 300usec for LXT971A) 1803 1804 CONFIG_PHY_CMD_DELAY (ppc4xx) 1805 1806 Some PHY like Intel LXT971A need extra delay after 1807 command issued before MII status register can be read 1808 1809- IP address: 1810 CONFIG_IPADDR 1811 1812 Define a default value for the IP address to use for 1813 the default Ethernet interface, in case this is not 1814 determined through e.g. bootp. 1815 (Environment variable "ipaddr") 1816 1817- Server IP address: 1818 CONFIG_SERVERIP 1819 1820 Defines a default value for the IP address of a TFTP 1821 server to contact when using the "tftboot" command. 1822 (Environment variable "serverip") 1823 1824 CONFIG_KEEP_SERVERADDR 1825 1826 Keeps the server's MAC address, in the env 'serveraddr' 1827 for passing to bootargs (like Linux's netconsole option) 1828 1829- Gateway IP address: 1830 CONFIG_GATEWAYIP 1831 1832 Defines a default value for the IP address of the 1833 default router where packets to other networks are 1834 sent to. 1835 (Environment variable "gatewayip") 1836 1837- Subnet mask: 1838 CONFIG_NETMASK 1839 1840 Defines a default value for the subnet mask (or 1841 routing prefix) which is used to determine if an IP 1842 address belongs to the local subnet or needs to be 1843 forwarded through a router. 1844 (Environment variable "netmask") 1845 1846- Multicast TFTP Mode: 1847 CONFIG_MCAST_TFTP 1848 1849 Defines whether you want to support multicast TFTP as per 1850 rfc-2090; for example to work with atftp. Lets lots of targets 1851 tftp down the same boot image concurrently. Note: the Ethernet 1852 driver in use must provide a function: mcast() to join/leave a 1853 multicast group. 1854 1855- BOOTP Recovery Mode: 1856 CONFIG_BOOTP_RANDOM_DELAY 1857 1858 If you have many targets in a network that try to 1859 boot using BOOTP, you may want to avoid that all 1860 systems send out BOOTP requests at precisely the same 1861 moment (which would happen for instance at recovery 1862 from a power failure, when all systems will try to 1863 boot, thus flooding the BOOTP server. Defining 1864 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be 1865 inserted before sending out BOOTP requests. The 1866 following delays are inserted then: 1867 1868 1st BOOTP request: delay 0 ... 1 sec 1869 2nd BOOTP request: delay 0 ... 2 sec 1870 3rd BOOTP request: delay 0 ... 4 sec 1871 4th and following 1872 BOOTP requests: delay 0 ... 8 sec 1873 1874 CONFIG_BOOTP_ID_CACHE_SIZE 1875 1876 BOOTP packets are uniquely identified using a 32-bit ID. The 1877 server will copy the ID from client requests to responses and 1878 U-Boot will use this to determine if it is the destination of 1879 an incoming response. Some servers will check that addresses 1880 aren't in use before handing them out (usually using an ARP 1881 ping) and therefore take up to a few hundred milliseconds to 1882 respond. Network congestion may also influence the time it 1883 takes for a response to make it back to the client. If that 1884 time is too long, U-Boot will retransmit requests. In order 1885 to allow earlier responses to still be accepted after these 1886 retransmissions, U-Boot's BOOTP client keeps a small cache of 1887 IDs. The CONFIG_BOOTP_ID_CACHE_SIZE controls the size of this 1888 cache. The default is to keep IDs for up to four outstanding 1889 requests. Increasing this will allow U-Boot to accept offers 1890 from a BOOTP client in networks with unusually high latency. 1891 1892- DHCP Advanced Options: 1893 You can fine tune the DHCP functionality by defining 1894 CONFIG_BOOTP_* symbols: 1895 1896 CONFIG_BOOTP_SUBNETMASK 1897 CONFIG_BOOTP_GATEWAY 1898 CONFIG_BOOTP_HOSTNAME 1899 CONFIG_BOOTP_NISDOMAIN 1900 CONFIG_BOOTP_BOOTPATH 1901 CONFIG_BOOTP_BOOTFILESIZE 1902 CONFIG_BOOTP_DNS 1903 CONFIG_BOOTP_DNS2 1904 CONFIG_BOOTP_SEND_HOSTNAME 1905 CONFIG_BOOTP_NTPSERVER 1906 CONFIG_BOOTP_TIMEOFFSET 1907 CONFIG_BOOTP_VENDOREX 1908 CONFIG_BOOTP_MAY_FAIL 1909 1910 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip 1911 environment variable, not the BOOTP server. 1912 1913 CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found 1914 after the configured retry count, the call will fail 1915 instead of starting over. This can be used to fail over 1916 to Link-local IP address configuration if the DHCP server 1917 is not available. 1918 1919 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS 1920 serverip from a DHCP server, it is possible that more 1921 than one DNS serverip is offered to the client. 1922 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS 1923 serverip will be stored in the additional environment 1924 variable "dnsip2". The first DNS serverip is always 1925 stored in the variable "dnsip", when CONFIG_BOOTP_DNS 1926 is defined. 1927 1928 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable 1929 to do a dynamic update of a DNS server. To do this, they 1930 need the hostname of the DHCP requester. 1931 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content 1932 of the "hostname" environment variable is passed as 1933 option 12 to the DHCP server. 1934 1935 CONFIG_BOOTP_DHCP_REQUEST_DELAY 1936 1937 A 32bit value in microseconds for a delay between 1938 receiving a "DHCP Offer" and sending the "DHCP Request". 1939 This fixes a problem with certain DHCP servers that don't 1940 respond 100% of the time to a "DHCP request". E.g. On an 1941 AT91RM9200 processor running at 180MHz, this delay needed 1942 to be *at least* 15,000 usec before a Windows Server 2003 1943 DHCP server would reply 100% of the time. I recommend at 1944 least 50,000 usec to be safe. The alternative is to hope 1945 that one of the retries will be successful but note that 1946 the DHCP timeout and retry process takes a longer than 1947 this delay. 1948 1949 - Link-local IP address negotiation: 1950 Negotiate with other link-local clients on the local network 1951 for an address that doesn't require explicit configuration. 1952 This is especially useful if a DHCP server cannot be guaranteed 1953 to exist in all environments that the device must operate. 1954 1955 See doc/README.link-local for more information. 1956 1957 - CDP Options: 1958 CONFIG_CDP_DEVICE_ID 1959 1960 The device id used in CDP trigger frames. 1961 1962 CONFIG_CDP_DEVICE_ID_PREFIX 1963 1964 A two character string which is prefixed to the MAC address 1965 of the device. 1966 1967 CONFIG_CDP_PORT_ID 1968 1969 A printf format string which contains the ascii name of 1970 the port. Normally is set to "eth%d" which sets 1971 eth0 for the first Ethernet, eth1 for the second etc. 1972 1973 CONFIG_CDP_CAPABILITIES 1974 1975 A 32bit integer which indicates the device capabilities; 1976 0x00000010 for a normal host which does not forwards. 1977 1978 CONFIG_CDP_VERSION 1979 1980 An ascii string containing the version of the software. 1981 1982 CONFIG_CDP_PLATFORM 1983 1984 An ascii string containing the name of the platform. 1985 1986 CONFIG_CDP_TRIGGER 1987 1988 A 32bit integer sent on the trigger. 1989 1990 CONFIG_CDP_POWER_CONSUMPTION 1991 1992 A 16bit integer containing the power consumption of the 1993 device in .1 of milliwatts. 1994 1995 CONFIG_CDP_APPLIANCE_VLAN_TYPE 1996 1997 A byte containing the id of the VLAN. 1998 1999- Status LED: CONFIG_LED_STATUS 2000 2001 Several configurations allow to display the current 2002 status using a LED. For instance, the LED will blink 2003 fast while running U-Boot code, stop blinking as 2004 soon as a reply to a BOOTP request was received, and 2005 start blinking slow once the Linux kernel is running 2006 (supported by a status LED driver in the Linux 2007 kernel). Defining CONFIG_LED_STATUS enables this 2008 feature in U-Boot. 2009 2010 Additional options: 2011 2012 CONFIG_LED_STATUS_GPIO 2013 The status LED can be connected to a GPIO pin. 2014 In such cases, the gpio_led driver can be used as a 2015 status LED backend implementation. Define CONFIG_LED_STATUS_GPIO 2016 to include the gpio_led driver in the U-Boot binary. 2017 2018 CONFIG_GPIO_LED_INVERTED_TABLE 2019 Some GPIO connected LEDs may have inverted polarity in which 2020 case the GPIO high value corresponds to LED off state and 2021 GPIO low value corresponds to LED on state. 2022 In such cases CONFIG_GPIO_LED_INVERTED_TABLE may be defined 2023 with a list of GPIO LEDs that have inverted polarity. 2024 2025- CAN Support: CONFIG_CAN_DRIVER 2026 2027 Defining CONFIG_CAN_DRIVER enables CAN driver support 2028 on those systems that support this (optional) 2029 feature, like the TQM8xxL modules. 2030 2031- I2C Support: CONFIG_SYS_I2C 2032 2033 This enable the NEW i2c subsystem, and will allow you to use 2034 i2c commands at the u-boot command line (as long as you set 2035 CONFIG_CMD_I2C in CONFIG_COMMANDS) and communicate with i2c 2036 based realtime clock chips or other i2c devices. See 2037 common/cmd_i2c.c for a description of the command line 2038 interface. 2039 2040 ported i2c driver to the new framework: 2041 - drivers/i2c/soft_i2c.c: 2042 - activate first bus with CONFIG_SYS_I2C_SOFT define 2043 CONFIG_SYS_I2C_SOFT_SPEED and CONFIG_SYS_I2C_SOFT_SLAVE 2044 for defining speed and slave address 2045 - activate second bus with I2C_SOFT_DECLARATIONS2 define 2046 CONFIG_SYS_I2C_SOFT_SPEED_2 and CONFIG_SYS_I2C_SOFT_SLAVE_2 2047 for defining speed and slave address 2048 - activate third bus with I2C_SOFT_DECLARATIONS3 define 2049 CONFIG_SYS_I2C_SOFT_SPEED_3 and CONFIG_SYS_I2C_SOFT_SLAVE_3 2050 for defining speed and slave address 2051 - activate fourth bus with I2C_SOFT_DECLARATIONS4 define 2052 CONFIG_SYS_I2C_SOFT_SPEED_4 and CONFIG_SYS_I2C_SOFT_SLAVE_4 2053 for defining speed and slave address 2054 2055 - drivers/i2c/fsl_i2c.c: 2056 - activate i2c driver with CONFIG_SYS_I2C_FSL 2057 define CONFIG_SYS_FSL_I2C_OFFSET for setting the register 2058 offset CONFIG_SYS_FSL_I2C_SPEED for the i2c speed and 2059 CONFIG_SYS_FSL_I2C_SLAVE for the slave addr of the first 2060 bus. 2061 - If your board supports a second fsl i2c bus, define 2062 CONFIG_SYS_FSL_I2C2_OFFSET for the register offset 2063 CONFIG_SYS_FSL_I2C2_SPEED for the speed and 2064 CONFIG_SYS_FSL_I2C2_SLAVE for the slave address of the 2065 second bus. 2066 2067 - drivers/i2c/tegra_i2c.c: 2068 - activate this driver with CONFIG_SYS_I2C_TEGRA 2069 - This driver adds 4 i2c buses with a fix speed from 2070 100000 and the slave addr 0! 2071 2072 - drivers/i2c/ppc4xx_i2c.c 2073 - activate this driver with CONFIG_SYS_I2C_PPC4XX 2074 - CONFIG_SYS_I2C_PPC4XX_CH0 activate hardware channel 0 2075 - CONFIG_SYS_I2C_PPC4XX_CH1 activate hardware channel 1 2076 2077 - drivers/i2c/i2c_mxc.c 2078 - activate this driver with CONFIG_SYS_I2C_MXC 2079 - enable bus 1 with CONFIG_SYS_I2C_MXC_I2C1 2080 - enable bus 2 with CONFIG_SYS_I2C_MXC_I2C2 2081 - enable bus 3 with CONFIG_SYS_I2C_MXC_I2C3 2082 - enable bus 4 with CONFIG_SYS_I2C_MXC_I2C4 2083 - define speed for bus 1 with CONFIG_SYS_MXC_I2C1_SPEED 2084 - define slave for bus 1 with CONFIG_SYS_MXC_I2C1_SLAVE 2085 - define speed for bus 2 with CONFIG_SYS_MXC_I2C2_SPEED 2086 - define slave for bus 2 with CONFIG_SYS_MXC_I2C2_SLAVE 2087 - define speed for bus 3 with CONFIG_SYS_MXC_I2C3_SPEED 2088 - define slave for bus 3 with CONFIG_SYS_MXC_I2C3_SLAVE 2089 - define speed for bus 4 with CONFIG_SYS_MXC_I2C4_SPEED 2090 - define slave for bus 4 with CONFIG_SYS_MXC_I2C4_SLAVE 2091 If those defines are not set, default value is 100000 2092 for speed, and 0 for slave. 2093 2094 - drivers/i2c/rcar_i2c.c: 2095 - activate this driver with CONFIG_SYS_I2C_RCAR 2096 - This driver adds 4 i2c buses 2097 2098 - CONFIG_SYS_RCAR_I2C0_BASE for setting the register channel 0 2099 - CONFIG_SYS_RCAR_I2C0_SPEED for for the speed channel 0 2100 - CONFIG_SYS_RCAR_I2C1_BASE for setting the register channel 1 2101 - CONFIG_SYS_RCAR_I2C1_SPEED for for the speed channel 1 2102 - CONFIG_SYS_RCAR_I2C2_BASE for setting the register channel 2 2103 - CONFIG_SYS_RCAR_I2C2_SPEED for for the speed channel 2 2104 - CONFIG_SYS_RCAR_I2C3_BASE for setting the register channel 3 2105 - CONFIG_SYS_RCAR_I2C3_SPEED for for the speed channel 3 2106 - CONFIF_SYS_RCAR_I2C_NUM_CONTROLLERS for number of i2c buses 2107 2108 - drivers/i2c/sh_i2c.c: 2109 - activate this driver with CONFIG_SYS_I2C_SH 2110 - This driver adds from 2 to 5 i2c buses 2111 2112 - CONFIG_SYS_I2C_SH_BASE0 for setting the register channel 0 2113 - CONFIG_SYS_I2C_SH_SPEED0 for for the speed channel 0 2114 - CONFIG_SYS_I2C_SH_BASE1 for setting the register channel 1 2115 - CONFIG_SYS_I2C_SH_SPEED1 for for the speed channel 1 2116 - CONFIG_SYS_I2C_SH_BASE2 for setting the register channel 2 2117 - CONFIG_SYS_I2C_SH_SPEED2 for for the speed channel 2 2118 - CONFIG_SYS_I2C_SH_BASE3 for setting the register channel 3 2119 - CONFIG_SYS_I2C_SH_SPEED3 for for the speed channel 3 2120 - CONFIG_SYS_I2C_SH_BASE4 for setting the register channel 4 2121 - CONFIG_SYS_I2C_SH_SPEED4 for for the speed channel 4 2122 - CONFIG_SYS_I2C_SH_NUM_CONTROLLERS for number of i2c buses 2123 2124 - drivers/i2c/omap24xx_i2c.c 2125 - activate this driver with CONFIG_SYS_I2C_OMAP24XX 2126 - CONFIG_SYS_OMAP24_I2C_SPEED speed channel 0 2127 - CONFIG_SYS_OMAP24_I2C_SLAVE slave addr channel 0 2128 - CONFIG_SYS_OMAP24_I2C_SPEED1 speed channel 1 2129 - CONFIG_SYS_OMAP24_I2C_SLAVE1 slave addr channel 1 2130 - CONFIG_SYS_OMAP24_I2C_SPEED2 speed channel 2 2131 - CONFIG_SYS_OMAP24_I2C_SLAVE2 slave addr channel 2 2132 - CONFIG_SYS_OMAP24_I2C_SPEED3 speed channel 3 2133 - CONFIG_SYS_OMAP24_I2C_SLAVE3 slave addr channel 3 2134 - CONFIG_SYS_OMAP24_I2C_SPEED4 speed channel 4 2135 - CONFIG_SYS_OMAP24_I2C_SLAVE4 slave addr channel 4 2136 2137 - drivers/i2c/zynq_i2c.c 2138 - activate this driver with CONFIG_SYS_I2C_ZYNQ 2139 - set CONFIG_SYS_I2C_ZYNQ_SPEED for speed setting 2140 - set CONFIG_SYS_I2C_ZYNQ_SLAVE for slave addr 2141 2142 - drivers/i2c/s3c24x0_i2c.c: 2143 - activate this driver with CONFIG_SYS_I2C_S3C24X0 2144 - This driver adds i2c buses (11 for Exynos5250, Exynos5420 2145 9 i2c buses for Exynos4 and 1 for S3C24X0 SoCs from Samsung) 2146 with a fix speed from 100000 and the slave addr 0! 2147 2148 - drivers/i2c/ihs_i2c.c 2149 - activate this driver with CONFIG_SYS_I2C_IHS 2150 - CONFIG_SYS_I2C_IHS_CH0 activate hardware channel 0 2151 - CONFIG_SYS_I2C_IHS_SPEED_0 speed channel 0 2152 - CONFIG_SYS_I2C_IHS_SLAVE_0 slave addr channel 0 2153 - CONFIG_SYS_I2C_IHS_CH1 activate hardware channel 1 2154 - CONFIG_SYS_I2C_IHS_SPEED_1 speed channel 1 2155 - CONFIG_SYS_I2C_IHS_SLAVE_1 slave addr channel 1 2156 - CONFIG_SYS_I2C_IHS_CH2 activate hardware channel 2 2157 - CONFIG_SYS_I2C_IHS_SPEED_2 speed channel 2 2158 - CONFIG_SYS_I2C_IHS_SLAVE_2 slave addr channel 2 2159 - CONFIG_SYS_I2C_IHS_CH3 activate hardware channel 3 2160 - CONFIG_SYS_I2C_IHS_SPEED_3 speed channel 3 2161 - CONFIG_SYS_I2C_IHS_SLAVE_3 slave addr channel 3 2162 - activate dual channel with CONFIG_SYS_I2C_IHS_DUAL 2163 - CONFIG_SYS_I2C_IHS_SPEED_0_1 speed channel 0_1 2164 - CONFIG_SYS_I2C_IHS_SLAVE_0_1 slave addr channel 0_1 2165 - CONFIG_SYS_I2C_IHS_SPEED_1_1 speed channel 1_1 2166 - CONFIG_SYS_I2C_IHS_SLAVE_1_1 slave addr channel 1_1 2167 - CONFIG_SYS_I2C_IHS_SPEED_2_1 speed channel 2_1 2168 - CONFIG_SYS_I2C_IHS_SLAVE_2_1 slave addr channel 2_1 2169 - CONFIG_SYS_I2C_IHS_SPEED_3_1 speed channel 3_1 2170 - CONFIG_SYS_I2C_IHS_SLAVE_3_1 slave addr channel 3_1 2171 2172 additional defines: 2173 2174 CONFIG_SYS_NUM_I2C_BUSES 2175 Hold the number of i2c buses you want to use. 2176 2177 CONFIG_SYS_I2C_DIRECT_BUS 2178 define this, if you don't use i2c muxes on your hardware. 2179 if CONFIG_SYS_I2C_MAX_HOPS is not defined or == 0 you can 2180 omit this define. 2181 2182 CONFIG_SYS_I2C_MAX_HOPS 2183 define how many muxes are maximal consecutively connected 2184 on one i2c bus. If you not use i2c muxes, omit this 2185 define. 2186 2187 CONFIG_SYS_I2C_BUSES 2188 hold a list of buses you want to use, only used if 2189 CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example 2190 a board with CONFIG_SYS_I2C_MAX_HOPS = 1 and 2191 CONFIG_SYS_NUM_I2C_BUSES = 9: 2192 2193 CONFIG_SYS_I2C_BUSES {{0, {I2C_NULL_HOP}}, \ 2194 {0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \ 2195 {0, {{I2C_MUX_PCA9547, 0x70, 2}}}, \ 2196 {0, {{I2C_MUX_PCA9547, 0x70, 3}}}, \ 2197 {0, {{I2C_MUX_PCA9547, 0x70, 4}}}, \ 2198 {0, {{I2C_MUX_PCA9547, 0x70, 5}}}, \ 2199 {1, {I2C_NULL_HOP}}, \ 2200 {1, {{I2C_MUX_PCA9544, 0x72, 1}}}, \ 2201 {1, {{I2C_MUX_PCA9544, 0x72, 2}}}, \ 2202 } 2203 2204 which defines 2205 bus 0 on adapter 0 without a mux 2206 bus 1 on adapter 0 with a PCA9547 on address 0x70 port 1 2207 bus 2 on adapter 0 with a PCA9547 on address 0x70 port 2 2208 bus 3 on adapter 0 with a PCA9547 on address 0x70 port 3 2209 bus 4 on adapter 0 with a PCA9547 on address 0x70 port 4 2210 bus 5 on adapter 0 with a PCA9547 on address 0x70 port 5 2211 bus 6 on adapter 1 without a mux 2212 bus 7 on adapter 1 with a PCA9544 on address 0x72 port 1 2213 bus 8 on adapter 1 with a PCA9544 on address 0x72 port 2 2214 2215 If you do not have i2c muxes on your board, omit this define. 2216 2217- Legacy I2C Support: CONFIG_HARD_I2C 2218 2219 NOTE: It is intended to move drivers to CONFIG_SYS_I2C which 2220 provides the following compelling advantages: 2221 2222 - more than one i2c adapter is usable 2223 - approved multibus support 2224 - better i2c mux support 2225 2226 ** Please consider updating your I2C driver now. ** 2227 2228 These enable legacy I2C serial bus commands. Defining 2229 CONFIG_HARD_I2C will include the appropriate I2C driver 2230 for the selected CPU. 2231 2232 This will allow you to use i2c commands at the u-boot 2233 command line (as long as you set CONFIG_CMD_I2C in 2234 CONFIG_COMMANDS) and communicate with i2c based realtime 2235 clock chips. See common/cmd_i2c.c for a description of the 2236 command line interface. 2237 2238 CONFIG_HARD_I2C selects a hardware I2C controller. 2239 2240 There are several other quantities that must also be 2241 defined when you define CONFIG_HARD_I2C. 2242 2243 In both cases you will need to define CONFIG_SYS_I2C_SPEED 2244 to be the frequency (in Hz) at which you wish your i2c bus 2245 to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie 2246 the CPU's i2c node address). 2247 2248 Now, the u-boot i2c code for the mpc8xx 2249 (arch/powerpc/cpu/mpc8xx/i2c.c) sets the CPU up as a master node 2250 and so its address should therefore be cleared to 0 (See, 2251 eg, MPC823e User's Manual p.16-473). So, set 2252 CONFIG_SYS_I2C_SLAVE to 0. 2253 2254 CONFIG_SYS_I2C_INIT_MPC5XXX 2255 2256 When a board is reset during an i2c bus transfer 2257 chips might think that the current transfer is still 2258 in progress. Reset the slave devices by sending start 2259 commands until the slave device responds. 2260 2261 That's all that's required for CONFIG_HARD_I2C. 2262 2263 If you use the software i2c interface (CONFIG_SYS_I2C_SOFT) 2264 then the following macros need to be defined (examples are 2265 from include/configs/lwmon.h): 2266 2267 I2C_INIT 2268 2269 (Optional). Any commands necessary to enable the I2C 2270 controller or configure ports. 2271 2272 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL) 2273 2274 I2C_PORT 2275 2276 (Only for MPC8260 CPU). The I/O port to use (the code 2277 assumes both bits are on the same port). Valid values 2278 are 0..3 for ports A..D. 2279 2280 I2C_ACTIVE 2281 2282 The code necessary to make the I2C data line active 2283 (driven). If the data line is open collector, this 2284 define can be null. 2285 2286 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA) 2287 2288 I2C_TRISTATE 2289 2290 The code necessary to make the I2C data line tri-stated 2291 (inactive). If the data line is open collector, this 2292 define can be null. 2293 2294 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA) 2295 2296 I2C_READ 2297 2298 Code that returns true if the I2C data line is high, 2299 false if it is low. 2300 2301 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0) 2302 2303 I2C_SDA(bit) 2304 2305 If <bit> is true, sets the I2C data line high. If it 2306 is false, it clears it (low). 2307 2308 eg: #define I2C_SDA(bit) \ 2309 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \ 2310 else immr->im_cpm.cp_pbdat &= ~PB_SDA 2311 2312 I2C_SCL(bit) 2313 2314 If <bit> is true, sets the I2C clock line high. If it 2315 is false, it clears it (low). 2316 2317 eg: #define I2C_SCL(bit) \ 2318 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \ 2319 else immr->im_cpm.cp_pbdat &= ~PB_SCL 2320 2321 I2C_DELAY 2322 2323 This delay is invoked four times per clock cycle so this 2324 controls the rate of data transfer. The data rate thus 2325 is 1 / (I2C_DELAY * 4). Often defined to be something 2326 like: 2327 2328 #define I2C_DELAY udelay(2) 2329 2330 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA 2331 2332 If your arch supports the generic GPIO framework (asm/gpio.h), 2333 then you may alternatively define the two GPIOs that are to be 2334 used as SCL / SDA. Any of the previous I2C_xxx macros will 2335 have GPIO-based defaults assigned to them as appropriate. 2336 2337 You should define these to the GPIO value as given directly to 2338 the generic GPIO functions. 2339 2340 CONFIG_SYS_I2C_INIT_BOARD 2341 2342 When a board is reset during an i2c bus transfer 2343 chips might think that the current transfer is still 2344 in progress. On some boards it is possible to access 2345 the i2c SCLK line directly, either by using the 2346 processor pin as a GPIO or by having a second pin 2347 connected to the bus. If this option is defined a 2348 custom i2c_init_board() routine in boards/xxx/board.c 2349 is run early in the boot sequence. 2350 2351 CONFIG_SYS_I2C_BOARD_LATE_INIT 2352 2353 An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is 2354 defined a custom i2c_board_late_init() routine in 2355 boards/xxx/board.c is run AFTER the operations in i2c_init() 2356 is completed. This callpoint can be used to unreset i2c bus 2357 using CPU i2c controller register accesses for CPUs whose i2c 2358 controller provide such a method. It is called at the end of 2359 i2c_init() to allow i2c_init operations to setup the i2c bus 2360 controller on the CPU (e.g. setting bus speed & slave address). 2361 2362 CONFIG_I2CFAST (PPC405GP|PPC405EP only) 2363 2364 This option enables configuration of bi_iic_fast[] flags 2365 in u-boot bd_info structure based on u-boot environment 2366 variable "i2cfast". (see also i2cfast) 2367 2368 CONFIG_I2C_MULTI_BUS 2369 2370 This option allows the use of multiple I2C buses, each of which 2371 must have a controller. At any point in time, only one bus is 2372 active. To switch to a different bus, use the 'i2c dev' command. 2373 Note that bus numbering is zero-based. 2374 2375 CONFIG_SYS_I2C_NOPROBES 2376 2377 This option specifies a list of I2C devices that will be skipped 2378 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS 2379 is set, specify a list of bus-device pairs. Otherwise, specify 2380 a 1D array of device addresses 2381 2382 e.g. 2383 #undef CONFIG_I2C_MULTI_BUS 2384 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68} 2385 2386 will skip addresses 0x50 and 0x68 on a board with one I2C bus 2387 2388 #define CONFIG_I2C_MULTI_BUS 2389 #define CONFIG_SYS_I2C_NOPROBES {{0,0x50},{0,0x68},{1,0x54}} 2390 2391 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1 2392 2393 CONFIG_SYS_SPD_BUS_NUM 2394 2395 If defined, then this indicates the I2C bus number for DDR SPD. 2396 If not defined, then U-Boot assumes that SPD is on I2C bus 0. 2397 2398 CONFIG_SYS_RTC_BUS_NUM 2399 2400 If defined, then this indicates the I2C bus number for the RTC. 2401 If not defined, then U-Boot assumes that RTC is on I2C bus 0. 2402 2403 CONFIG_SYS_DTT_BUS_NUM 2404 2405 If defined, then this indicates the I2C bus number for the DTT. 2406 If not defined, then U-Boot assumes that DTT is on I2C bus 0. 2407 2408 CONFIG_SYS_I2C_DTT_ADDR: 2409 2410 If defined, specifies the I2C address of the DTT device. 2411 If not defined, then U-Boot uses predefined value for 2412 specified DTT device. 2413 2414 CONFIG_SOFT_I2C_READ_REPEATED_START 2415 2416 defining this will force the i2c_read() function in 2417 the soft_i2c driver to perform an I2C repeated start 2418 between writing the address pointer and reading the 2419 data. If this define is omitted the default behaviour 2420 of doing a stop-start sequence will be used. Most I2C 2421 devices can use either method, but some require one or 2422 the other. 2423 2424- SPI Support: CONFIG_SPI 2425 2426 Enables SPI driver (so far only tested with 2427 SPI EEPROM, also an instance works with Crystal A/D and 2428 D/As on the SACSng board) 2429 2430 CONFIG_SH_SPI 2431 2432 Enables the driver for SPI controller on SuperH. Currently 2433 only SH7757 is supported. 2434 2435 CONFIG_SOFT_SPI 2436 2437 Enables a software (bit-bang) SPI driver rather than 2438 using hardware support. This is a general purpose 2439 driver that only requires three general I/O port pins 2440 (two outputs, one input) to function. If this is 2441 defined, the board configuration must define several 2442 SPI configuration items (port pins to use, etc). For 2443 an example, see include/configs/sacsng.h. 2444 2445 CONFIG_HARD_SPI 2446 2447 Enables a hardware SPI driver for general-purpose reads 2448 and writes. As with CONFIG_SOFT_SPI, the board configuration 2449 must define a list of chip-select function pointers. 2450 Currently supported on some MPC8xxx processors. For an 2451 example, see include/configs/mpc8349emds.h. 2452 2453 CONFIG_MXC_SPI 2454 2455 Enables the driver for the SPI controllers on i.MX and MXC 2456 SoCs. Currently i.MX31/35/51 are supported. 2457 2458 CONFIG_SYS_SPI_MXC_WAIT 2459 Timeout for waiting until spi transfer completed. 2460 default: (CONFIG_SYS_HZ/100) /* 10 ms */ 2461 2462- FPGA Support: CONFIG_FPGA 2463 2464 Enables FPGA subsystem. 2465 2466 CONFIG_FPGA_<vendor> 2467 2468 Enables support for specific chip vendors. 2469 (ALTERA, XILINX) 2470 2471 CONFIG_FPGA_<family> 2472 2473 Enables support for FPGA family. 2474 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX) 2475 2476 CONFIG_FPGA_COUNT 2477 2478 Specify the number of FPGA devices to support. 2479 2480 CONFIG_CMD_FPGA_LOADMK 2481 2482 Enable support for fpga loadmk command 2483 2484 CONFIG_CMD_FPGA_LOADP 2485 2486 Enable support for fpga loadp command - load partial bitstream 2487 2488 CONFIG_CMD_FPGA_LOADBP 2489 2490 Enable support for fpga loadbp command - load partial bitstream 2491 (Xilinx only) 2492 2493 CONFIG_SYS_FPGA_PROG_FEEDBACK 2494 2495 Enable printing of hash marks during FPGA configuration. 2496 2497 CONFIG_SYS_FPGA_CHECK_BUSY 2498 2499 Enable checks on FPGA configuration interface busy 2500 status by the configuration function. This option 2501 will require a board or device specific function to 2502 be written. 2503 2504 CONFIG_FPGA_DELAY 2505 2506 If defined, a function that provides delays in the FPGA 2507 configuration driver. 2508 2509 CONFIG_SYS_FPGA_CHECK_CTRLC 2510 Allow Control-C to interrupt FPGA configuration 2511 2512 CONFIG_SYS_FPGA_CHECK_ERROR 2513 2514 Check for configuration errors during FPGA bitfile 2515 loading. For example, abort during Virtex II 2516 configuration if the INIT_B line goes low (which 2517 indicated a CRC error). 2518 2519 CONFIG_SYS_FPGA_WAIT_INIT 2520 2521 Maximum time to wait for the INIT_B line to de-assert 2522 after PROB_B has been de-asserted during a Virtex II 2523 FPGA configuration sequence. The default time is 500 2524 ms. 2525 2526 CONFIG_SYS_FPGA_WAIT_BUSY 2527 2528 Maximum time to wait for BUSY to de-assert during 2529 Virtex II FPGA configuration. The default is 5 ms. 2530 2531 CONFIG_SYS_FPGA_WAIT_CONFIG 2532 2533 Time to wait after FPGA configuration. The default is 2534 200 ms. 2535 2536- Configuration Management: 2537 CONFIG_BUILD_TARGET 2538 2539 Some SoCs need special image types (e.g. U-Boot binary 2540 with a special header) as build targets. By defining 2541 CONFIG_BUILD_TARGET in the SoC / board header, this 2542 special image will be automatically built upon calling 2543 make / buildman. 2544 2545 CONFIG_IDENT_STRING 2546 2547 If defined, this string will be added to the U-Boot 2548 version information (U_BOOT_VERSION) 2549 2550- Vendor Parameter Protection: 2551 2552 U-Boot considers the values of the environment 2553 variables "serial#" (Board Serial Number) and 2554 "ethaddr" (Ethernet Address) to be parameters that 2555 are set once by the board vendor / manufacturer, and 2556 protects these variables from casual modification by 2557 the user. Once set, these variables are read-only, 2558 and write or delete attempts are rejected. You can 2559 change this behaviour: 2560 2561 If CONFIG_ENV_OVERWRITE is #defined in your config 2562 file, the write protection for vendor parameters is 2563 completely disabled. Anybody can change or delete 2564 these parameters. 2565 2566 Alternatively, if you define _both_ an ethaddr in the 2567 default env _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default 2568 Ethernet address is installed in the environment, 2569 which can be changed exactly ONCE by the user. [The 2570 serial# is unaffected by this, i. e. it remains 2571 read-only.] 2572 2573 The same can be accomplished in a more flexible way 2574 for any variable by configuring the type of access 2575 to allow for those variables in the ".flags" variable 2576 or define CONFIG_ENV_FLAGS_LIST_STATIC. 2577 2578- Protected RAM: 2579 CONFIG_PRAM 2580 2581 Define this variable to enable the reservation of 2582 "protected RAM", i. e. RAM which is not overwritten 2583 by U-Boot. Define CONFIG_PRAM to hold the number of 2584 kB you want to reserve for pRAM. You can overwrite 2585 this default value by defining an environment 2586 variable "pram" to the number of kB you want to 2587 reserve. Note that the board info structure will 2588 still show the full amount of RAM. If pRAM is 2589 reserved, a new environment variable "mem" will 2590 automatically be defined to hold the amount of 2591 remaining RAM in a form that can be passed as boot 2592 argument to Linux, for instance like that: 2593 2594 setenv bootargs ... mem=\${mem} 2595 saveenv 2596 2597 This way you can tell Linux not to use this memory, 2598 either, which results in a memory region that will 2599 not be affected by reboots. 2600 2601 *WARNING* If your board configuration uses automatic 2602 detection of the RAM size, you must make sure that 2603 this memory test is non-destructive. So far, the 2604 following board configurations are known to be 2605 "pRAM-clean": 2606 2607 IVMS8, IVML24, SPD8xx, TQM8xxL, 2608 HERMES, IP860, RPXlite, LWMON, 2609 FLAGADM, TQM8260 2610 2611- Access to physical memory region (> 4GB) 2612 Some basic support is provided for operations on memory not 2613 normally accessible to U-Boot - e.g. some architectures 2614 support access to more than 4GB of memory on 32-bit 2615 machines using physical address extension or similar. 2616 Define CONFIG_PHYSMEM to access this basic support, which 2617 currently only supports clearing the memory. 2618 2619- Error Recovery: 2620 CONFIG_PANIC_HANG 2621 2622 Define this variable to stop the system in case of a 2623 fatal error, so that you have to reset it manually. 2624 This is probably NOT a good idea for an embedded 2625 system where you want the system to reboot 2626 automatically as fast as possible, but it may be 2627 useful during development since you can try to debug 2628 the conditions that lead to the situation. 2629 2630 CONFIG_NET_RETRY_COUNT 2631 2632 This variable defines the number of retries for 2633 network operations like ARP, RARP, TFTP, or BOOTP 2634 before giving up the operation. If not defined, a 2635 default value of 5 is used. 2636 2637 CONFIG_ARP_TIMEOUT 2638 2639 Timeout waiting for an ARP reply in milliseconds. 2640 2641 CONFIG_NFS_TIMEOUT 2642 2643 Timeout in milliseconds used in NFS protocol. 2644 If you encounter "ERROR: Cannot umount" in nfs command, 2645 try longer timeout such as 2646 #define CONFIG_NFS_TIMEOUT 10000UL 2647 2648- Command Interpreter: 2649 CONFIG_AUTO_COMPLETE 2650 2651 Enable auto completion of commands using TAB. 2652 2653 CONFIG_SYS_PROMPT_HUSH_PS2 2654 2655 This defines the secondary prompt string, which is 2656 printed when the command interpreter needs more input 2657 to complete a command. Usually "> ". 2658 2659 Note: 2660 2661 In the current implementation, the local variables 2662 space and global environment variables space are 2663 separated. Local variables are those you define by 2664 simply typing `name=value'. To access a local 2665 variable later on, you have write `$name' or 2666 `${name}'; to execute the contents of a variable 2667 directly type `$name' at the command prompt. 2668 2669 Global environment variables are those you use 2670 setenv/printenv to work with. To run a command stored 2671 in such a variable, you need to use the run command, 2672 and you must not use the '$' sign to access them. 2673 2674 To store commands and special characters in a 2675 variable, please use double quotation marks 2676 surrounding the whole text of the variable, instead 2677 of the backslashes before semicolons and special 2678 symbols. 2679 2680- Command Line Editing and History: 2681 CONFIG_CMDLINE_EDITING 2682 2683 Enable editing and History functions for interactive 2684 command line input operations 2685 2686- Command Line PS1/PS2 support: 2687 CONFIG_CMDLINE_PS_SUPPORT 2688 2689 Enable support for changing the command prompt string 2690 at run-time. Only static string is supported so far. 2691 The string is obtained from environment variables PS1 2692 and PS2. 2693 2694- Default Environment: 2695 CONFIG_EXTRA_ENV_SETTINGS 2696 2697 Define this to contain any number of null terminated 2698 strings (variable = value pairs) that will be part of 2699 the default environment compiled into the boot image. 2700 2701 For example, place something like this in your 2702 board's config file: 2703 2704 #define CONFIG_EXTRA_ENV_SETTINGS \ 2705 "myvar1=value1\0" \ 2706 "myvar2=value2\0" 2707 2708 Warning: This method is based on knowledge about the 2709 internal format how the environment is stored by the 2710 U-Boot code. This is NOT an official, exported 2711 interface! Although it is unlikely that this format 2712 will change soon, there is no guarantee either. 2713 You better know what you are doing here. 2714 2715 Note: overly (ab)use of the default environment is 2716 discouraged. Make sure to check other ways to preset 2717 the environment like the "source" command or the 2718 boot command first. 2719 2720 CONFIG_ENV_VARS_UBOOT_CONFIG 2721 2722 Define this in order to add variables describing the 2723 U-Boot build configuration to the default environment. 2724 These will be named arch, cpu, board, vendor, and soc. 2725 2726 Enabling this option will cause the following to be defined: 2727 2728 - CONFIG_SYS_ARCH 2729 - CONFIG_SYS_CPU 2730 - CONFIG_SYS_BOARD 2731 - CONFIG_SYS_VENDOR 2732 - CONFIG_SYS_SOC 2733 2734 CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG 2735 2736 Define this in order to add variables describing certain 2737 run-time determined information about the hardware to the 2738 environment. These will be named board_name, board_rev. 2739 2740 CONFIG_DELAY_ENVIRONMENT 2741 2742 Normally the environment is loaded when the board is 2743 initialised so that it is available to U-Boot. This inhibits 2744 that so that the environment is not available until 2745 explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL 2746 this is instead controlled by the value of 2747 /config/load-environment. 2748 2749- DataFlash Support: 2750 CONFIG_HAS_DATAFLASH 2751 2752 Defining this option enables DataFlash features and 2753 allows to read/write in Dataflash via the standard 2754 commands cp, md... 2755 2756- Serial Flash support 2757 CONFIG_CMD_SF 2758 2759 Defining this option enables SPI flash commands 2760 'sf probe/read/write/erase/update'. 2761 2762 Usage requires an initial 'probe' to define the serial 2763 flash parameters, followed by read/write/erase/update 2764 commands. 2765 2766 The following defaults may be provided by the platform 2767 to handle the common case when only a single serial 2768 flash is present on the system. 2769 2770 CONFIG_SF_DEFAULT_BUS Bus identifier 2771 CONFIG_SF_DEFAULT_CS Chip-select 2772 CONFIG_SF_DEFAULT_MODE (see include/spi.h) 2773 CONFIG_SF_DEFAULT_SPEED in Hz 2774 2775 CONFIG_CMD_SF_TEST 2776 2777 Define this option to include a destructive SPI flash 2778 test ('sf test'). 2779 2780 CONFIG_SF_DUAL_FLASH Dual flash memories 2781 2782 Define this option to use dual flash support where two flash 2783 memories can be connected with a given cs line. 2784 Currently Xilinx Zynq qspi supports these type of connections. 2785 2786- SystemACE Support: 2787 CONFIG_SYSTEMACE 2788 2789 Adding this option adds support for Xilinx SystemACE 2790 chips attached via some sort of local bus. The address 2791 of the chip must also be defined in the 2792 CONFIG_SYS_SYSTEMACE_BASE macro. For example: 2793 2794 #define CONFIG_SYSTEMACE 2795 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000 2796 2797 When SystemACE support is added, the "ace" device type 2798 becomes available to the fat commands, i.e. fatls. 2799 2800- TFTP Fixed UDP Port: 2801 CONFIG_TFTP_PORT 2802 2803 If this is defined, the environment variable tftpsrcp 2804 is used to supply the TFTP UDP source port value. 2805 If tftpsrcp isn't defined, the normal pseudo-random port 2806 number generator is used. 2807 2808 Also, the environment variable tftpdstp is used to supply 2809 the TFTP UDP destination port value. If tftpdstp isn't 2810 defined, the normal port 69 is used. 2811 2812 The purpose for tftpsrcp is to allow a TFTP server to 2813 blindly start the TFTP transfer using the pre-configured 2814 target IP address and UDP port. This has the effect of 2815 "punching through" the (Windows XP) firewall, allowing 2816 the remainder of the TFTP transfer to proceed normally. 2817 A better solution is to properly configure the firewall, 2818 but sometimes that is not allowed. 2819 2820- Hashing support: 2821 CONFIG_CMD_HASH 2822 2823 This enables a generic 'hash' command which can produce 2824 hashes / digests from a few algorithms (e.g. SHA1, SHA256). 2825 2826 CONFIG_HASH_VERIFY 2827 2828 Enable the hash verify command (hash -v). This adds to code 2829 size a little. 2830 2831 CONFIG_SHA1 - This option enables support of hashing using SHA1 2832 algorithm. The hash is calculated in software. 2833 CONFIG_SHA256 - This option enables support of hashing using 2834 SHA256 algorithm. The hash is calculated in software. 2835 CONFIG_SHA_HW_ACCEL - This option enables hardware acceleration 2836 for SHA1/SHA256 hashing. 2837 This affects the 'hash' command and also the 2838 hash_lookup_algo() function. 2839 CONFIG_SHA_PROG_HW_ACCEL - This option enables 2840 hardware-acceleration for SHA1/SHA256 progressive hashing. 2841 Data can be streamed in a block at a time and the hashing 2842 is performed in hardware. 2843 2844 Note: There is also a sha1sum command, which should perhaps 2845 be deprecated in favour of 'hash sha1'. 2846 2847- Freescale i.MX specific commands: 2848 CONFIG_CMD_HDMIDETECT 2849 This enables 'hdmidet' command which returns true if an 2850 HDMI monitor is detected. This command is i.MX 6 specific. 2851 2852 CONFIG_CMD_BMODE 2853 This enables the 'bmode' (bootmode) command for forcing 2854 a boot from specific media. 2855 2856 This is useful for forcing the ROM's usb downloader to 2857 activate upon a watchdog reset which is nice when iterating 2858 on U-Boot. Using the reset button or running bmode normal 2859 will set it back to normal. This command currently 2860 supports i.MX53 and i.MX6. 2861 2862- bootcount support: 2863 CONFIG_BOOTCOUNT_LIMIT 2864 2865 This enables the bootcounter support, see: 2866 http://www.denx.de/wiki/DULG/UBootBootCountLimit 2867 2868 CONFIG_AT91SAM9XE 2869 enable special bootcounter support on at91sam9xe based boards. 2870 CONFIG_SOC_DA8XX 2871 enable special bootcounter support on da850 based boards. 2872 CONFIG_BOOTCOUNT_RAM 2873 enable support for the bootcounter in RAM 2874 CONFIG_BOOTCOUNT_I2C 2875 enable support for the bootcounter on an i2c (like RTC) device. 2876 CONFIG_SYS_I2C_RTC_ADDR = i2c chip address 2877 CONFIG_SYS_BOOTCOUNT_ADDR = i2c addr which is used for 2878 the bootcounter. 2879 CONFIG_BOOTCOUNT_ALEN = address len 2880 2881- Show boot progress: 2882 CONFIG_SHOW_BOOT_PROGRESS 2883 2884 Defining this option allows to add some board- 2885 specific code (calling a user-provided function 2886 "show_boot_progress(int)") that enables you to show 2887 the system's boot progress on some display (for 2888 example, some LED's) on your board. At the moment, 2889 the following checkpoints are implemented: 2890 2891 2892Legacy uImage format: 2893 2894 Arg Where When 2895 1 common/cmd_bootm.c before attempting to boot an image 2896 -1 common/cmd_bootm.c Image header has bad magic number 2897 2 common/cmd_bootm.c Image header has correct magic number 2898 -2 common/cmd_bootm.c Image header has bad checksum 2899 3 common/cmd_bootm.c Image header has correct checksum 2900 -3 common/cmd_bootm.c Image data has bad checksum 2901 4 common/cmd_bootm.c Image data has correct checksum 2902 -4 common/cmd_bootm.c Image is for unsupported architecture 2903 5 common/cmd_bootm.c Architecture check OK 2904 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi) 2905 6 common/cmd_bootm.c Image Type check OK 2906 -6 common/cmd_bootm.c gunzip uncompression error 2907 -7 common/cmd_bootm.c Unimplemented compression type 2908 7 common/cmd_bootm.c Uncompression OK 2909 8 common/cmd_bootm.c No uncompress/copy overwrite error 2910 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX) 2911 2912 9 common/image.c Start initial ramdisk verification 2913 -10 common/image.c Ramdisk header has bad magic number 2914 -11 common/image.c Ramdisk header has bad checksum 2915 10 common/image.c Ramdisk header is OK 2916 -12 common/image.c Ramdisk data has bad checksum 2917 11 common/image.c Ramdisk data has correct checksum 2918 12 common/image.c Ramdisk verification complete, start loading 2919 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk) 2920 13 common/image.c Start multifile image verification 2921 14 common/image.c No initial ramdisk, no multifile, continue. 2922 2923 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS 2924 2925 -30 arch/powerpc/lib/board.c Fatal error, hang the system 2926 -31 post/post.c POST test failed, detected by post_output_backlog() 2927 -32 post/post.c POST test failed, detected by post_run_single() 2928 2929 34 common/cmd_doc.c before loading a Image from a DOC device 2930 -35 common/cmd_doc.c Bad usage of "doc" command 2931 35 common/cmd_doc.c correct usage of "doc" command 2932 -36 common/cmd_doc.c No boot device 2933 36 common/cmd_doc.c correct boot device 2934 -37 common/cmd_doc.c Unknown Chip ID on boot device 2935 37 common/cmd_doc.c correct chip ID found, device available 2936 -38 common/cmd_doc.c Read Error on boot device 2937 38 common/cmd_doc.c reading Image header from DOC device OK 2938 -39 common/cmd_doc.c Image header has bad magic number 2939 39 common/cmd_doc.c Image header has correct magic number 2940 -40 common/cmd_doc.c Error reading Image from DOC device 2941 40 common/cmd_doc.c Image header has correct magic number 2942 41 common/cmd_ide.c before loading a Image from a IDE device 2943 -42 common/cmd_ide.c Bad usage of "ide" command 2944 42 common/cmd_ide.c correct usage of "ide" command 2945 -43 common/cmd_ide.c No boot device 2946 43 common/cmd_ide.c boot device found 2947 -44 common/cmd_ide.c Device not available 2948 44 common/cmd_ide.c Device available 2949 -45 common/cmd_ide.c wrong partition selected 2950 45 common/cmd_ide.c partition selected 2951 -46 common/cmd_ide.c Unknown partition table 2952 46 common/cmd_ide.c valid partition table found 2953 -47 common/cmd_ide.c Invalid partition type 2954 47 common/cmd_ide.c correct partition type 2955 -48 common/cmd_ide.c Error reading Image Header on boot device 2956 48 common/cmd_ide.c reading Image Header from IDE device OK 2957 -49 common/cmd_ide.c Image header has bad magic number 2958 49 common/cmd_ide.c Image header has correct magic number 2959 -50 common/cmd_ide.c Image header has bad checksum 2960 50 common/cmd_ide.c Image header has correct checksum 2961 -51 common/cmd_ide.c Error reading Image from IDE device 2962 51 common/cmd_ide.c reading Image from IDE device OK 2963 52 common/cmd_nand.c before loading a Image from a NAND device 2964 -53 common/cmd_nand.c Bad usage of "nand" command 2965 53 common/cmd_nand.c correct usage of "nand" command 2966 -54 common/cmd_nand.c No boot device 2967 54 common/cmd_nand.c boot device found 2968 -55 common/cmd_nand.c Unknown Chip ID on boot device 2969 55 common/cmd_nand.c correct chip ID found, device available 2970 -56 common/cmd_nand.c Error reading Image Header on boot device 2971 56 common/cmd_nand.c reading Image Header from NAND device OK 2972 -57 common/cmd_nand.c Image header has bad magic number 2973 57 common/cmd_nand.c Image header has correct magic number 2974 -58 common/cmd_nand.c Error reading Image from NAND device 2975 58 common/cmd_nand.c reading Image from NAND device OK 2976 2977 -60 common/env_common.c Environment has a bad CRC, using default 2978 2979 64 net/eth.c starting with Ethernet configuration. 2980 -64 net/eth.c no Ethernet found. 2981 65 net/eth.c Ethernet found. 2982 2983 -80 common/cmd_net.c usage wrong 2984 80 common/cmd_net.c before calling net_loop() 2985 -81 common/cmd_net.c some error in net_loop() occurred 2986 81 common/cmd_net.c net_loop() back without error 2987 -82 common/cmd_net.c size == 0 (File with size 0 loaded) 2988 82 common/cmd_net.c trying automatic boot 2989 83 common/cmd_net.c running "source" command 2990 -83 common/cmd_net.c some error in automatic boot or "source" command 2991 84 common/cmd_net.c end without errors 2992 2993FIT uImage format: 2994 2995 Arg Where When 2996 100 common/cmd_bootm.c Kernel FIT Image has correct format 2997 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format 2998 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration 2999 -101 common/cmd_bootm.c Can't get configuration for kernel subimage 3000 102 common/cmd_bootm.c Kernel unit name specified 3001 -103 common/cmd_bootm.c Can't get kernel subimage node offset 3002 103 common/cmd_bootm.c Found configuration node 3003 104 common/cmd_bootm.c Got kernel subimage node offset 3004 -104 common/cmd_bootm.c Kernel subimage hash verification failed 3005 105 common/cmd_bootm.c Kernel subimage hash verification OK 3006 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture 3007 106 common/cmd_bootm.c Architecture check OK 3008 -106 common/cmd_bootm.c Kernel subimage has wrong type 3009 107 common/cmd_bootm.c Kernel subimage type OK 3010 -107 common/cmd_bootm.c Can't get kernel subimage data/size 3011 108 common/cmd_bootm.c Got kernel subimage data/size 3012 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT) 3013 -109 common/cmd_bootm.c Can't get kernel subimage type 3014 -110 common/cmd_bootm.c Can't get kernel subimage comp 3015 -111 common/cmd_bootm.c Can't get kernel subimage os 3016 -112 common/cmd_bootm.c Can't get kernel subimage load address 3017 -113 common/cmd_bootm.c Image uncompress/copy overwrite error 3018 3019 120 common/image.c Start initial ramdisk verification 3020 -120 common/image.c Ramdisk FIT image has incorrect format 3021 121 common/image.c Ramdisk FIT image has correct format 3022 122 common/image.c No ramdisk subimage unit name, using configuration 3023 -122 common/image.c Can't get configuration for ramdisk subimage 3024 123 common/image.c Ramdisk unit name specified 3025 -124 common/image.c Can't get ramdisk subimage node offset 3026 125 common/image.c Got ramdisk subimage node offset 3027 -125 common/image.c Ramdisk subimage hash verification failed 3028 126 common/image.c Ramdisk subimage hash verification OK 3029 -126 common/image.c Ramdisk subimage for unsupported architecture 3030 127 common/image.c Architecture check OK 3031 -127 common/image.c Can't get ramdisk subimage data/size 3032 128 common/image.c Got ramdisk subimage data/size 3033 129 common/image.c Can't get ramdisk load address 3034 -129 common/image.c Got ramdisk load address 3035 3036 -130 common/cmd_doc.c Incorrect FIT image format 3037 131 common/cmd_doc.c FIT image format OK 3038 3039 -140 common/cmd_ide.c Incorrect FIT image format 3040 141 common/cmd_ide.c FIT image format OK 3041 3042 -150 common/cmd_nand.c Incorrect FIT image format 3043 151 common/cmd_nand.c FIT image format OK 3044 3045- legacy image format: 3046 CONFIG_IMAGE_FORMAT_LEGACY 3047 enables the legacy image format support in U-Boot. 3048 3049 Default: 3050 enabled if CONFIG_FIT_SIGNATURE is not defined. 3051 3052 CONFIG_DISABLE_IMAGE_LEGACY 3053 disable the legacy image format 3054 3055 This define is introduced, as the legacy image format is 3056 enabled per default for backward compatibility. 3057 3058- FIT image support: 3059 CONFIG_FIT_DISABLE_SHA256 3060 Supporting SHA256 hashes has quite an impact on binary size. 3061 For constrained systems sha256 hash support can be disabled 3062 with this option. 3063 3064 TODO(sjg@chromium.org): Adjust this option to be positive, 3065 and move it to Kconfig 3066 3067- Standalone program support: 3068 CONFIG_STANDALONE_LOAD_ADDR 3069 3070 This option defines a board specific value for the 3071 address where standalone program gets loaded, thus 3072 overwriting the architecture dependent default 3073 settings. 3074 3075- Frame Buffer Address: 3076 CONFIG_FB_ADDR 3077 3078 Define CONFIG_FB_ADDR if you want to use specific 3079 address for frame buffer. This is typically the case 3080 when using a graphics controller has separate video 3081 memory. U-Boot will then place the frame buffer at 3082 the given address instead of dynamically reserving it 3083 in system RAM by calling lcd_setmem(), which grabs 3084 the memory for the frame buffer depending on the 3085 configured panel size. 3086 3087 Please see board_init_f function. 3088 3089- Automatic software updates via TFTP server 3090 CONFIG_UPDATE_TFTP 3091 CONFIG_UPDATE_TFTP_CNT_MAX 3092 CONFIG_UPDATE_TFTP_MSEC_MAX 3093 3094 These options enable and control the auto-update feature; 3095 for a more detailed description refer to doc/README.update. 3096 3097- MTD Support (mtdparts command, UBI support) 3098 CONFIG_MTD_DEVICE 3099 3100 Adds the MTD device infrastructure from the Linux kernel. 3101 Needed for mtdparts command support. 3102 3103 CONFIG_MTD_PARTITIONS 3104 3105 Adds the MTD partitioning infrastructure from the Linux 3106 kernel. Needed for UBI support. 3107 3108- UBI support 3109 CONFIG_CMD_UBI 3110 3111 Adds commands for interacting with MTD partitions formatted 3112 with the UBI flash translation layer 3113 3114 Requires also defining CONFIG_RBTREE 3115 3116 CONFIG_UBI_SILENCE_MSG 3117 3118 Make the verbose messages from UBI stop printing. This leaves 3119 warnings and errors enabled. 3120 3121 3122 CONFIG_MTD_UBI_WL_THRESHOLD 3123 This parameter defines the maximum difference between the highest 3124 erase counter value and the lowest erase counter value of eraseblocks 3125 of UBI devices. When this threshold is exceeded, UBI starts performing 3126 wear leveling by means of moving data from eraseblock with low erase 3127 counter to eraseblocks with high erase counter. 3128 3129 The default value should be OK for SLC NAND flashes, NOR flashes and 3130 other flashes which have eraseblock life-cycle 100000 or more. 3131 However, in case of MLC NAND flashes which typically have eraseblock 3132 life-cycle less than 10000, the threshold should be lessened (e.g., 3133 to 128 or 256, although it does not have to be power of 2). 3134 3135 default: 4096 3136 3137 CONFIG_MTD_UBI_BEB_LIMIT 3138 This option specifies the maximum bad physical eraseblocks UBI 3139 expects on the MTD device (per 1024 eraseblocks). If the 3140 underlying flash does not admit of bad eraseblocks (e.g. NOR 3141 flash), this value is ignored. 3142 3143 NAND datasheets often specify the minimum and maximum NVM 3144 (Number of Valid Blocks) for the flashes' endurance lifetime. 3145 The maximum expected bad eraseblocks per 1024 eraseblocks 3146 then can be calculated as "1024 * (1 - MinNVB / MaxNVB)", 3147 which gives 20 for most NANDs (MaxNVB is basically the total 3148 count of eraseblocks on the chip). 3149 3150 To put it differently, if this value is 20, UBI will try to 3151 reserve about 1.9% of physical eraseblocks for bad blocks 3152 handling. And that will be 1.9% of eraseblocks on the entire 3153 NAND chip, not just the MTD partition UBI attaches. This means 3154 that if you have, say, a NAND flash chip admits maximum 40 bad 3155 eraseblocks, and it is split on two MTD partitions of the same 3156 size, UBI will reserve 40 eraseblocks when attaching a 3157 partition. 3158 3159 default: 20 3160 3161 CONFIG_MTD_UBI_FASTMAP 3162 Fastmap is a mechanism which allows attaching an UBI device 3163 in nearly constant time. Instead of scanning the whole MTD device it 3164 only has to locate a checkpoint (called fastmap) on the device. 3165 The on-flash fastmap contains all information needed to attach 3166 the device. Using fastmap makes only sense on large devices where 3167 attaching by scanning takes long. UBI will not automatically install 3168 a fastmap on old images, but you can set the UBI parameter 3169 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT to 1 if you want so. Please note 3170 that fastmap-enabled images are still usable with UBI implementations 3171 without fastmap support. On typical flash devices the whole fastmap 3172 fits into one PEB. UBI will reserve PEBs to hold two fastmaps. 3173 3174 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT 3175 Set this parameter to enable fastmap automatically on images 3176 without a fastmap. 3177 default: 0 3178 3179 CONFIG_MTD_UBI_FM_DEBUG 3180 Enable UBI fastmap debug 3181 default: 0 3182 3183- UBIFS support 3184 CONFIG_CMD_UBIFS 3185 3186 Adds commands for interacting with UBI volumes formatted as 3187 UBIFS. UBIFS is read-only in u-boot. 3188 3189 Requires UBI support as well as CONFIG_LZO 3190 3191 CONFIG_UBIFS_SILENCE_MSG 3192 3193 Make the verbose messages from UBIFS stop printing. This leaves 3194 warnings and errors enabled. 3195 3196- SPL framework 3197 CONFIG_SPL 3198 Enable building of SPL globally. 3199 3200 CONFIG_SPL_LDSCRIPT 3201 LDSCRIPT for linking the SPL binary. 3202 3203 CONFIG_SPL_MAX_FOOTPRINT 3204 Maximum size in memory allocated to the SPL, BSS included. 3205 When defined, the linker checks that the actual memory 3206 used by SPL from _start to __bss_end does not exceed it. 3207 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE 3208 must not be both defined at the same time. 3209 3210 CONFIG_SPL_MAX_SIZE 3211 Maximum size of the SPL image (text, data, rodata, and 3212 linker lists sections), BSS excluded. 3213 When defined, the linker checks that the actual size does 3214 not exceed it. 3215 3216 CONFIG_SPL_TEXT_BASE 3217 TEXT_BASE for linking the SPL binary. 3218 3219 CONFIG_SPL_RELOC_TEXT_BASE 3220 Address to relocate to. If unspecified, this is equal to 3221 CONFIG_SPL_TEXT_BASE (i.e. no relocation is done). 3222 3223 CONFIG_SPL_BSS_START_ADDR 3224 Link address for the BSS within the SPL binary. 3225 3226 CONFIG_SPL_BSS_MAX_SIZE 3227 Maximum size in memory allocated to the SPL BSS. 3228 When defined, the linker checks that the actual memory used 3229 by SPL from __bss_start to __bss_end does not exceed it. 3230 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE 3231 must not be both defined at the same time. 3232 3233 CONFIG_SPL_STACK 3234 Adress of the start of the stack SPL will use 3235 3236 CONFIG_SPL_PANIC_ON_RAW_IMAGE 3237 When defined, SPL will panic() if the image it has 3238 loaded does not have a signature. 3239 Defining this is useful when code which loads images 3240 in SPL cannot guarantee that absolutely all read errors 3241 will be caught. 3242 An example is the LPC32XX MLC NAND driver, which will 3243 consider that a completely unreadable NAND block is bad, 3244 and thus should be skipped silently. 3245 3246 CONFIG_SPL_RELOC_STACK 3247 Adress of the start of the stack SPL will use after 3248 relocation. If unspecified, this is equal to 3249 CONFIG_SPL_STACK. 3250 3251 CONFIG_SYS_SPL_MALLOC_START 3252 Starting address of the malloc pool used in SPL. 3253 When this option is set the full malloc is used in SPL and 3254 it is set up by spl_init() and before that, the simple malloc() 3255 can be used if CONFIG_SYS_MALLOC_F is defined. 3256 3257 CONFIG_SYS_SPL_MALLOC_SIZE 3258 The size of the malloc pool used in SPL. 3259 3260 CONFIG_SPL_FRAMEWORK 3261 Enable the SPL framework under common/. This framework 3262 supports MMC, NAND and YMODEM loading of U-Boot and NAND 3263 NAND loading of the Linux Kernel. 3264 3265 CONFIG_SPL_OS_BOOT 3266 Enable booting directly to an OS from SPL. 3267 See also: doc/README.falcon 3268 3269 CONFIG_SPL_DISPLAY_PRINT 3270 For ARM, enable an optional function to print more information 3271 about the running system. 3272 3273 CONFIG_SPL_INIT_MINIMAL 3274 Arch init code should be built for a very small image 3275 3276 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_PARTITION 3277 Partition on the MMC to load U-Boot from when the MMC is being 3278 used in raw mode 3279 3280 CONFIG_SYS_MMCSD_RAW_MODE_KERNEL_SECTOR 3281 Sector to load kernel uImage from when MMC is being 3282 used in raw mode (for Falcon mode) 3283 3284 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTOR, 3285 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTORS 3286 Sector and number of sectors to load kernel argument 3287 parameters from when MMC is being used in raw mode 3288 (for falcon mode) 3289 3290 CONFIG_SYS_MMCSD_FS_BOOT_PARTITION 3291 Partition on the MMC to load U-Boot from when the MMC is being 3292 used in fs mode 3293 3294 CONFIG_SPL_FS_LOAD_PAYLOAD_NAME 3295 Filename to read to load U-Boot when reading from filesystem 3296 3297 CONFIG_SPL_FS_LOAD_KERNEL_NAME 3298 Filename to read to load kernel uImage when reading 3299 from filesystem (for Falcon mode) 3300 3301 CONFIG_SPL_FS_LOAD_ARGS_NAME 3302 Filename to read to load kernel argument parameters 3303 when reading from filesystem (for Falcon mode) 3304 3305 CONFIG_SPL_MPC83XX_WAIT_FOR_NAND 3306 Set this for NAND SPL on PPC mpc83xx targets, so that 3307 start.S waits for the rest of the SPL to load before 3308 continuing (the hardware starts execution after just 3309 loading the first page rather than the full 4K). 3310 3311 CONFIG_SPL_SKIP_RELOCATE 3312 Avoid SPL relocation 3313 3314 CONFIG_SPL_NAND_BASE 3315 Include nand_base.c in the SPL. Requires 3316 CONFIG_SPL_NAND_DRIVERS. 3317 3318 CONFIG_SPL_NAND_DRIVERS 3319 SPL uses normal NAND drivers, not minimal drivers. 3320 3321 CONFIG_SPL_NAND_ECC 3322 Include standard software ECC in the SPL 3323 3324 CONFIG_SPL_NAND_SIMPLE 3325 Support for NAND boot using simple NAND drivers that 3326 expose the cmd_ctrl() interface. 3327 3328 CONFIG_SPL_UBI 3329 Support for a lightweight UBI (fastmap) scanner and 3330 loader 3331 3332 CONFIG_SPL_NAND_RAW_ONLY 3333 Support to boot only raw u-boot.bin images. Use this only 3334 if you need to save space. 3335 3336 CONFIG_SPL_COMMON_INIT_DDR 3337 Set for common ddr init with serial presence detect in 3338 SPL binary. 3339 3340 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT, 3341 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE, 3342 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS, 3343 CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE, 3344 CONFIG_SYS_NAND_ECCBYTES 3345 Defines the size and behavior of the NAND that SPL uses 3346 to read U-Boot 3347 3348 CONFIG_SPL_NAND_BOOT 3349 Add support NAND boot 3350 3351 CONFIG_SYS_NAND_U_BOOT_OFFS 3352 Location in NAND to read U-Boot from 3353 3354 CONFIG_SYS_NAND_U_BOOT_DST 3355 Location in memory to load U-Boot to 3356 3357 CONFIG_SYS_NAND_U_BOOT_SIZE 3358 Size of image to load 3359 3360 CONFIG_SYS_NAND_U_BOOT_START 3361 Entry point in loaded image to jump to 3362 3363 CONFIG_SYS_NAND_HW_ECC_OOBFIRST 3364 Define this if you need to first read the OOB and then the 3365 data. This is used, for example, on davinci platforms. 3366 3367 CONFIG_SPL_OMAP3_ID_NAND 3368 Support for an OMAP3-specific set of functions to return the 3369 ID and MFR of the first attached NAND chip, if present. 3370 3371 CONFIG_SPL_RAM_DEVICE 3372 Support for running image already present in ram, in SPL binary 3373 3374 CONFIG_SPL_PAD_TO 3375 Image offset to which the SPL should be padded before appending 3376 the SPL payload. By default, this is defined as 3377 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined. 3378 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL 3379 payload without any padding, or >= CONFIG_SPL_MAX_SIZE. 3380 3381 CONFIG_SPL_TARGET 3382 Final target image containing SPL and payload. Some SPLs 3383 use an arch-specific makefile fragment instead, for 3384 example if more than one image needs to be produced. 3385 3386 CONFIG_FIT_SPL_PRINT 3387 Printing information about a FIT image adds quite a bit of 3388 code to SPL. So this is normally disabled in SPL. Use this 3389 option to re-enable it. This will affect the output of the 3390 bootm command when booting a FIT image. 3391 3392- TPL framework 3393 CONFIG_TPL 3394 Enable building of TPL globally. 3395 3396 CONFIG_TPL_PAD_TO 3397 Image offset to which the TPL should be padded before appending 3398 the TPL payload. By default, this is defined as 3399 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined. 3400 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL 3401 payload without any padding, or >= CONFIG_SPL_MAX_SIZE. 3402 3403- Interrupt support (PPC): 3404 3405 There are common interrupt_init() and timer_interrupt() 3406 for all PPC archs. interrupt_init() calls interrupt_init_cpu() 3407 for CPU specific initialization. interrupt_init_cpu() 3408 should set decrementer_count to appropriate value. If 3409 CPU resets decrementer automatically after interrupt 3410 (ppc4xx) it should set decrementer_count to zero. 3411 timer_interrupt() calls timer_interrupt_cpu() for CPU 3412 specific handling. If board has watchdog / status_led 3413 / other_activity_monitor it works automatically from 3414 general timer_interrupt(). 3415 3416 3417Board initialization settings: 3418------------------------------ 3419 3420During Initialization u-boot calls a number of board specific functions 3421to allow the preparation of board specific prerequisites, e.g. pin setup 3422before drivers are initialized. To enable these callbacks the 3423following configuration macros have to be defined. Currently this is 3424architecture specific, so please check arch/your_architecture/lib/board.c 3425typically in board_init_f() and board_init_r(). 3426 3427- CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f() 3428- CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r() 3429- CONFIG_BOARD_LATE_INIT: Call board_late_init() 3430- CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init() 3431 3432Configuration Settings: 3433----------------------- 3434 3435- CONFIG_SYS_SUPPORT_64BIT_DATA: Defined automatically if compiled as 64-bit. 3436 Optionally it can be defined to support 64-bit memory commands. 3437 3438- CONFIG_SYS_LONGHELP: Defined when you want long help messages included; 3439 undefine this when you're short of memory. 3440 3441- CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default 3442 width of the commands listed in the 'help' command output. 3443 3444- CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to 3445 prompt for user input. 3446 3447- CONFIG_SYS_CBSIZE: Buffer size for input from the Console 3448 3449- CONFIG_SYS_PBSIZE: Buffer size for Console output 3450 3451- CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands 3452 3453- CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to 3454 the application (usually a Linux kernel) when it is 3455 booted 3456 3457- CONFIG_SYS_BAUDRATE_TABLE: 3458 List of legal baudrate settings for this board. 3459 3460- CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END: 3461 Begin and End addresses of the area used by the 3462 simple memory test. 3463 3464- CONFIG_SYS_ALT_MEMTEST: 3465 Enable an alternate, more extensive memory test. 3466 3467- CONFIG_SYS_MEMTEST_SCRATCH: 3468 Scratch address used by the alternate memory test 3469 You only need to set this if address zero isn't writeable 3470 3471- CONFIG_SYS_MEM_RESERVE_SECURE 3472 Only implemented for ARMv8 for now. 3473 If defined, the size of CONFIG_SYS_MEM_RESERVE_SECURE memory 3474 is substracted from total RAM and won't be reported to OS. 3475 This memory can be used as secure memory. A variable 3476 gd->arch.secure_ram is used to track the location. In systems 3477 the RAM base is not zero, or RAM is divided into banks, 3478 this variable needs to be recalcuated to get the address. 3479 3480- CONFIG_SYS_MEM_TOP_HIDE: 3481 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header, 3482 this specified memory area will get subtracted from the top 3483 (end) of RAM and won't get "touched" at all by U-Boot. By 3484 fixing up gd->ram_size the Linux kernel should gets passed 3485 the now "corrected" memory size and won't touch it either. 3486 This should work for arch/ppc and arch/powerpc. Only Linux 3487 board ports in arch/powerpc with bootwrapper support that 3488 recalculate the memory size from the SDRAM controller setup 3489 will have to get fixed in Linux additionally. 3490 3491 This option can be used as a workaround for the 440EPx/GRx 3492 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't 3493 be touched. 3494 3495 WARNING: Please make sure that this value is a multiple of 3496 the Linux page size (normally 4k). If this is not the case, 3497 then the end address of the Linux memory will be located at a 3498 non page size aligned address and this could cause major 3499 problems. 3500 3501- CONFIG_SYS_LOADS_BAUD_CHANGE: 3502 Enable temporary baudrate change while serial download 3503 3504- CONFIG_SYS_SDRAM_BASE: 3505 Physical start address of SDRAM. _Must_ be 0 here. 3506 3507- CONFIG_SYS_FLASH_BASE: 3508 Physical start address of Flash memory. 3509 3510- CONFIG_SYS_MONITOR_BASE: 3511 Physical start address of boot monitor code (set by 3512 make config files to be same as the text base address 3513 (CONFIG_SYS_TEXT_BASE) used when linking) - same as 3514 CONFIG_SYS_FLASH_BASE when booting from flash. 3515 3516- CONFIG_SYS_MONITOR_LEN: 3517 Size of memory reserved for monitor code, used to 3518 determine _at_compile_time_ (!) if the environment is 3519 embedded within the U-Boot image, or in a separate 3520 flash sector. 3521 3522- CONFIG_SYS_MALLOC_LEN: 3523 Size of DRAM reserved for malloc() use. 3524 3525- CONFIG_SYS_MALLOC_F_LEN 3526 Size of the malloc() pool for use before relocation. If 3527 this is defined, then a very simple malloc() implementation 3528 will become available before relocation. The address is just 3529 below the global data, and the stack is moved down to make 3530 space. 3531 3532 This feature allocates regions with increasing addresses 3533 within the region. calloc() is supported, but realloc() 3534 is not available. free() is supported but does nothing. 3535 The memory will be freed (or in fact just forgotten) when 3536 U-Boot relocates itself. 3537 3538- CONFIG_SYS_MALLOC_SIMPLE 3539 Provides a simple and small malloc() and calloc() for those 3540 boards which do not use the full malloc in SPL (which is 3541 enabled with CONFIG_SYS_SPL_MALLOC_START). 3542 3543- CONFIG_SYS_NONCACHED_MEMORY: 3544 Size of non-cached memory area. This area of memory will be 3545 typically located right below the malloc() area and mapped 3546 uncached in the MMU. This is useful for drivers that would 3547 otherwise require a lot of explicit cache maintenance. For 3548 some drivers it's also impossible to properly maintain the 3549 cache. For example if the regions that need to be flushed 3550 are not a multiple of the cache-line size, *and* padding 3551 cannot be allocated between the regions to align them (i.e. 3552 if the HW requires a contiguous array of regions, and the 3553 size of each region is not cache-aligned), then a flush of 3554 one region may result in overwriting data that hardware has 3555 written to another region in the same cache-line. This can 3556 happen for example in network drivers where descriptors for 3557 buffers are typically smaller than the CPU cache-line (e.g. 3558 16 bytes vs. 32 or 64 bytes). 3559 3560 Non-cached memory is only supported on 32-bit ARM at present. 3561 3562- CONFIG_SYS_BOOTM_LEN: 3563 Normally compressed uImages are limited to an 3564 uncompressed size of 8 MBytes. If this is not enough, 3565 you can define CONFIG_SYS_BOOTM_LEN in your board config file 3566 to adjust this setting to your needs. 3567 3568- CONFIG_SYS_BOOTMAPSZ: 3569 Maximum size of memory mapped by the startup code of 3570 the Linux kernel; all data that must be processed by 3571 the Linux kernel (bd_info, boot arguments, FDT blob if 3572 used) must be put below this limit, unless "bootm_low" 3573 environment variable is defined and non-zero. In such case 3574 all data for the Linux kernel must be between "bootm_low" 3575 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment 3576 variable "bootm_mapsize" will override the value of 3577 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined, 3578 then the value in "bootm_size" will be used instead. 3579 3580- CONFIG_SYS_BOOT_RAMDISK_HIGH: 3581 Enable initrd_high functionality. If defined then the 3582 initrd_high feature is enabled and the bootm ramdisk subcommand 3583 is enabled. 3584 3585- CONFIG_SYS_BOOT_GET_CMDLINE: 3586 Enables allocating and saving kernel cmdline in space between 3587 "bootm_low" and "bootm_low" + BOOTMAPSZ. 3588 3589- CONFIG_SYS_BOOT_GET_KBD: 3590 Enables allocating and saving a kernel copy of the bd_info in 3591 space between "bootm_low" and "bootm_low" + BOOTMAPSZ. 3592 3593- CONFIG_SYS_MAX_FLASH_BANKS: 3594 Max number of Flash memory banks 3595 3596- CONFIG_SYS_MAX_FLASH_SECT: 3597 Max number of sectors on a Flash chip 3598 3599- CONFIG_SYS_FLASH_ERASE_TOUT: 3600 Timeout for Flash erase operations (in ms) 3601 3602- CONFIG_SYS_FLASH_WRITE_TOUT: 3603 Timeout for Flash write operations (in ms) 3604 3605- CONFIG_SYS_FLASH_LOCK_TOUT 3606 Timeout for Flash set sector lock bit operation (in ms) 3607 3608- CONFIG_SYS_FLASH_UNLOCK_TOUT 3609 Timeout for Flash clear lock bits operation (in ms) 3610 3611- CONFIG_SYS_FLASH_PROTECTION 3612 If defined, hardware flash sectors protection is used 3613 instead of U-Boot software protection. 3614 3615- CONFIG_SYS_DIRECT_FLASH_TFTP: 3616 3617 Enable TFTP transfers directly to flash memory; 3618 without this option such a download has to be 3619 performed in two steps: (1) download to RAM, and (2) 3620 copy from RAM to flash. 3621 3622 The two-step approach is usually more reliable, since 3623 you can check if the download worked before you erase 3624 the flash, but in some situations (when system RAM is 3625 too limited to allow for a temporary copy of the 3626 downloaded image) this option may be very useful. 3627 3628- CONFIG_SYS_FLASH_CFI: 3629 Define if the flash driver uses extra elements in the 3630 common flash structure for storing flash geometry. 3631 3632- CONFIG_FLASH_CFI_DRIVER 3633 This option also enables the building of the cfi_flash driver 3634 in the drivers directory 3635 3636- CONFIG_FLASH_CFI_MTD 3637 This option enables the building of the cfi_mtd driver 3638 in the drivers directory. The driver exports CFI flash 3639 to the MTD layer. 3640 3641- CONFIG_SYS_FLASH_USE_BUFFER_WRITE 3642 Use buffered writes to flash. 3643 3644- CONFIG_FLASH_SPANSION_S29WS_N 3645 s29ws-n MirrorBit flash has non-standard addresses for buffered 3646 write commands. 3647 3648- CONFIG_SYS_FLASH_QUIET_TEST 3649 If this option is defined, the common CFI flash doesn't 3650 print it's warning upon not recognized FLASH banks. This 3651 is useful, if some of the configured banks are only 3652 optionally available. 3653 3654- CONFIG_FLASH_SHOW_PROGRESS 3655 If defined (must be an integer), print out countdown 3656 digits and dots. Recommended value: 45 (9..1) for 80 3657 column displays, 15 (3..1) for 40 column displays. 3658 3659- CONFIG_FLASH_VERIFY 3660 If defined, the content of the flash (destination) is compared 3661 against the source after the write operation. An error message 3662 will be printed when the contents are not identical. 3663 Please note that this option is useless in nearly all cases, 3664 since such flash programming errors usually are detected earlier 3665 while unprotecting/erasing/programming. Please only enable 3666 this option if you really know what you are doing. 3667 3668- CONFIG_SYS_RX_ETH_BUFFER: 3669 Defines the number of Ethernet receive buffers. On some 3670 Ethernet controllers it is recommended to set this value 3671 to 8 or even higher (EEPRO100 or 405 EMAC), since all 3672 buffers can be full shortly after enabling the interface 3673 on high Ethernet traffic. 3674 Defaults to 4 if not defined. 3675 3676- CONFIG_ENV_MAX_ENTRIES 3677 3678 Maximum number of entries in the hash table that is used 3679 internally to store the environment settings. The default 3680 setting is supposed to be generous and should work in most 3681 cases. This setting can be used to tune behaviour; see 3682 lib/hashtable.c for details. 3683 3684- CONFIG_ENV_FLAGS_LIST_DEFAULT 3685- CONFIG_ENV_FLAGS_LIST_STATIC 3686 Enable validation of the values given to environment variables when 3687 calling env set. Variables can be restricted to only decimal, 3688 hexadecimal, or boolean. If CONFIG_CMD_NET is also defined, 3689 the variables can also be restricted to IP address or MAC address. 3690 3691 The format of the list is: 3692 type_attribute = [s|d|x|b|i|m] 3693 access_attribute = [a|r|o|c] 3694 attributes = type_attribute[access_attribute] 3695 entry = variable_name[:attributes] 3696 list = entry[,list] 3697 3698 The type attributes are: 3699 s - String (default) 3700 d - Decimal 3701 x - Hexadecimal 3702 b - Boolean ([1yYtT|0nNfF]) 3703 i - IP address 3704 m - MAC address 3705 3706 The access attributes are: 3707 a - Any (default) 3708 r - Read-only 3709 o - Write-once 3710 c - Change-default 3711 3712 - CONFIG_ENV_FLAGS_LIST_DEFAULT 3713 Define this to a list (string) to define the ".flags" 3714 environment variable in the default or embedded environment. 3715 3716 - CONFIG_ENV_FLAGS_LIST_STATIC 3717 Define this to a list (string) to define validation that 3718 should be done if an entry is not found in the ".flags" 3719 environment variable. To override a setting in the static 3720 list, simply add an entry for the same variable name to the 3721 ".flags" variable. 3722 3723 If CONFIG_REGEX is defined, the variable_name above is evaluated as a 3724 regular expression. This allows multiple variables to define the same 3725 flags without explicitly listing them for each variable. 3726 3727- CONFIG_ENV_ACCESS_IGNORE_FORCE 3728 If defined, don't allow the -f switch to env set override variable 3729 access flags. 3730 3731- CONFIG_OMAP_PLATFORM_RESET_TIME_MAX_USEC (OMAP only) 3732 This is set by OMAP boards for the max time that reset should 3733 be asserted. See doc/README.omap-reset-time for details on how 3734 the value can be calculated on a given board. 3735 3736- CONFIG_USE_STDINT 3737 If stdint.h is available with your toolchain you can define this 3738 option to enable it. You can provide option 'USE_STDINT=1' when 3739 building U-Boot to enable this. 3740 3741The following definitions that deal with the placement and management 3742of environment data (variable area); in general, we support the 3743following configurations: 3744 3745- CONFIG_BUILD_ENVCRC: 3746 3747 Builds up envcrc with the target environment so that external utils 3748 may easily extract it and embed it in final U-Boot images. 3749 3750- CONFIG_ENV_IS_IN_FLASH: 3751 3752 Define this if the environment is in flash memory. 3753 3754 a) The environment occupies one whole flash sector, which is 3755 "embedded" in the text segment with the U-Boot code. This 3756 happens usually with "bottom boot sector" or "top boot 3757 sector" type flash chips, which have several smaller 3758 sectors at the start or the end. For instance, such a 3759 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In 3760 such a case you would place the environment in one of the 3761 4 kB sectors - with U-Boot code before and after it. With 3762 "top boot sector" type flash chips, you would put the 3763 environment in one of the last sectors, leaving a gap 3764 between U-Boot and the environment. 3765 3766 - CONFIG_ENV_OFFSET: 3767 3768 Offset of environment data (variable area) to the 3769 beginning of flash memory; for instance, with bottom boot 3770 type flash chips the second sector can be used: the offset 3771 for this sector is given here. 3772 3773 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE. 3774 3775 - CONFIG_ENV_ADDR: 3776 3777 This is just another way to specify the start address of 3778 the flash sector containing the environment (instead of 3779 CONFIG_ENV_OFFSET). 3780 3781 - CONFIG_ENV_SECT_SIZE: 3782 3783 Size of the sector containing the environment. 3784 3785 3786 b) Sometimes flash chips have few, equal sized, BIG sectors. 3787 In such a case you don't want to spend a whole sector for 3788 the environment. 3789 3790 - CONFIG_ENV_SIZE: 3791 3792 If you use this in combination with CONFIG_ENV_IS_IN_FLASH 3793 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part 3794 of this flash sector for the environment. This saves 3795 memory for the RAM copy of the environment. 3796 3797 It may also save flash memory if you decide to use this 3798 when your environment is "embedded" within U-Boot code, 3799 since then the remainder of the flash sector could be used 3800 for U-Boot code. It should be pointed out that this is 3801 STRONGLY DISCOURAGED from a robustness point of view: 3802 updating the environment in flash makes it always 3803 necessary to erase the WHOLE sector. If something goes 3804 wrong before the contents has been restored from a copy in 3805 RAM, your target system will be dead. 3806 3807 - CONFIG_ENV_ADDR_REDUND 3808 CONFIG_ENV_SIZE_REDUND 3809 3810 These settings describe a second storage area used to hold 3811 a redundant copy of the environment data, so that there is 3812 a valid backup copy in case there is a power failure during 3813 a "saveenv" operation. 3814 3815BE CAREFUL! Any changes to the flash layout, and some changes to the 3816source code will make it necessary to adapt <board>/u-boot.lds* 3817accordingly! 3818 3819 3820- CONFIG_ENV_IS_IN_NVRAM: 3821 3822 Define this if you have some non-volatile memory device 3823 (NVRAM, battery buffered SRAM) which you want to use for the 3824 environment. 3825 3826 - CONFIG_ENV_ADDR: 3827 - CONFIG_ENV_SIZE: 3828 3829 These two #defines are used to determine the memory area you 3830 want to use for environment. It is assumed that this memory 3831 can just be read and written to, without any special 3832 provision. 3833 3834BE CAREFUL! The first access to the environment happens quite early 3835in U-Boot initialization (when we try to get the setting of for the 3836console baudrate). You *MUST* have mapped your NVRAM area then, or 3837U-Boot will hang. 3838 3839Please note that even with NVRAM we still use a copy of the 3840environment in RAM: we could work on NVRAM directly, but we want to 3841keep settings there always unmodified except somebody uses "saveenv" 3842to save the current settings. 3843 3844 3845- CONFIG_ENV_IS_IN_EEPROM: 3846 3847 Use this if you have an EEPROM or similar serial access 3848 device and a driver for it. 3849 3850 - CONFIG_ENV_OFFSET: 3851 - CONFIG_ENV_SIZE: 3852 3853 These two #defines specify the offset and size of the 3854 environment area within the total memory of your EEPROM. 3855 3856 - CONFIG_SYS_I2C_EEPROM_ADDR: 3857 If defined, specified the chip address of the EEPROM device. 3858 The default address is zero. 3859 3860 - CONFIG_SYS_I2C_EEPROM_BUS: 3861 If defined, specified the i2c bus of the EEPROM device. 3862 3863 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS: 3864 If defined, the number of bits used to address bytes in a 3865 single page in the EEPROM device. A 64 byte page, for example 3866 would require six bits. 3867 3868 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS: 3869 If defined, the number of milliseconds to delay between 3870 page writes. The default is zero milliseconds. 3871 3872 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN: 3873 The length in bytes of the EEPROM memory array address. Note 3874 that this is NOT the chip address length! 3875 3876 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW: 3877 EEPROM chips that implement "address overflow" are ones 3878 like Catalyst 24WC04/08/16 which has 9/10/11 bits of 3879 address and the extra bits end up in the "chip address" bit 3880 slots. This makes a 24WC08 (1Kbyte) chip look like four 256 3881 byte chips. 3882 3883 Note that we consider the length of the address field to 3884 still be one byte because the extra address bits are hidden 3885 in the chip address. 3886 3887 - CONFIG_SYS_EEPROM_SIZE: 3888 The size in bytes of the EEPROM device. 3889 3890 - CONFIG_ENV_EEPROM_IS_ON_I2C 3891 define this, if you have I2C and SPI activated, and your 3892 EEPROM, which holds the environment, is on the I2C bus. 3893 3894 - CONFIG_I2C_ENV_EEPROM_BUS 3895 if you have an Environment on an EEPROM reached over 3896 I2C muxes, you can define here, how to reach this 3897 EEPROM. For example: 3898 3899 #define CONFIG_I2C_ENV_EEPROM_BUS 1 3900 3901 EEPROM which holds the environment, is reached over 3902 a pca9547 i2c mux with address 0x70, channel 3. 3903 3904- CONFIG_ENV_IS_IN_DATAFLASH: 3905 3906 Define this if you have a DataFlash memory device which you 3907 want to use for the environment. 3908 3909 - CONFIG_ENV_OFFSET: 3910 - CONFIG_ENV_ADDR: 3911 - CONFIG_ENV_SIZE: 3912 3913 These three #defines specify the offset and size of the 3914 environment area within the total memory of your DataFlash placed 3915 at the specified address. 3916 3917- CONFIG_ENV_IS_IN_SPI_FLASH: 3918 3919 Define this if you have a SPI Flash memory device which you 3920 want to use for the environment. 3921 3922 - CONFIG_ENV_OFFSET: 3923 - CONFIG_ENV_SIZE: 3924 3925 These two #defines specify the offset and size of the 3926 environment area within the SPI Flash. CONFIG_ENV_OFFSET must be 3927 aligned to an erase sector boundary. 3928 3929 - CONFIG_ENV_SECT_SIZE: 3930 3931 Define the SPI flash's sector size. 3932 3933 - CONFIG_ENV_OFFSET_REDUND (optional): 3934 3935 This setting describes a second storage area of CONFIG_ENV_SIZE 3936 size used to hold a redundant copy of the environment data, so 3937 that there is a valid backup copy in case there is a power failure 3938 during a "saveenv" operation. CONFIG_ENV_OFFSET_REDUND must be 3939 aligned to an erase sector boundary. 3940 3941 - CONFIG_ENV_SPI_BUS (optional): 3942 - CONFIG_ENV_SPI_CS (optional): 3943 3944 Define the SPI bus and chip select. If not defined they will be 0. 3945 3946 - CONFIG_ENV_SPI_MAX_HZ (optional): 3947 3948 Define the SPI max work clock. If not defined then use 1MHz. 3949 3950 - CONFIG_ENV_SPI_MODE (optional): 3951 3952 Define the SPI work mode. If not defined then use SPI_MODE_3. 3953 3954- CONFIG_ENV_IS_IN_REMOTE: 3955 3956 Define this if you have a remote memory space which you 3957 want to use for the local device's environment. 3958 3959 - CONFIG_ENV_ADDR: 3960 - CONFIG_ENV_SIZE: 3961 3962 These two #defines specify the address and size of the 3963 environment area within the remote memory space. The 3964 local device can get the environment from remote memory 3965 space by SRIO or PCIE links. 3966 3967BE CAREFUL! For some special cases, the local device can not use 3968"saveenv" command. For example, the local device will get the 3969environment stored in a remote NOR flash by SRIO or PCIE link, 3970but it can not erase, write this NOR flash by SRIO or PCIE interface. 3971 3972- CONFIG_ENV_IS_IN_NAND: 3973 3974 Define this if you have a NAND device which you want to use 3975 for the environment. 3976 3977 - CONFIG_ENV_OFFSET: 3978 - CONFIG_ENV_SIZE: 3979 3980 These two #defines specify the offset and size of the environment 3981 area within the first NAND device. CONFIG_ENV_OFFSET must be 3982 aligned to an erase block boundary. 3983 3984 - CONFIG_ENV_OFFSET_REDUND (optional): 3985 3986 This setting describes a second storage area of CONFIG_ENV_SIZE 3987 size used to hold a redundant copy of the environment data, so 3988 that there is a valid backup copy in case there is a power failure 3989 during a "saveenv" operation. CONFIG_ENV_OFFSET_REDUND must be 3990 aligned to an erase block boundary. 3991 3992 - CONFIG_ENV_RANGE (optional): 3993 3994 Specifies the length of the region in which the environment 3995 can be written. This should be a multiple of the NAND device's 3996 block size. Specifying a range with more erase blocks than 3997 are needed to hold CONFIG_ENV_SIZE allows bad blocks within 3998 the range to be avoided. 3999 4000 - CONFIG_ENV_OFFSET_OOB (optional): 4001 4002 Enables support for dynamically retrieving the offset of the 4003 environment from block zero's out-of-band data. The 4004 "nand env.oob" command can be used to record this offset. 4005 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when 4006 using CONFIG_ENV_OFFSET_OOB. 4007 4008- CONFIG_NAND_ENV_DST 4009 4010 Defines address in RAM to which the nand_spl code should copy the 4011 environment. If redundant environment is used, it will be copied to 4012 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE. 4013 4014- CONFIG_ENV_IS_IN_UBI: 4015 4016 Define this if you have an UBI volume that you want to use for the 4017 environment. This has the benefit of wear-leveling the environment 4018 accesses, which is important on NAND. 4019 4020 - CONFIG_ENV_UBI_PART: 4021 4022 Define this to a string that is the mtd partition containing the UBI. 4023 4024 - CONFIG_ENV_UBI_VOLUME: 4025 4026 Define this to the name of the volume that you want to store the 4027 environment in. 4028 4029 - CONFIG_ENV_UBI_VOLUME_REDUND: 4030 4031 Define this to the name of another volume to store a second copy of 4032 the environment in. This will enable redundant environments in UBI. 4033 It is assumed that both volumes are in the same MTD partition. 4034 4035 - CONFIG_UBI_SILENCE_MSG 4036 - CONFIG_UBIFS_SILENCE_MSG 4037 4038 You will probably want to define these to avoid a really noisy system 4039 when storing the env in UBI. 4040 4041- CONFIG_ENV_IS_IN_FAT: 4042 Define this if you want to use the FAT file system for the environment. 4043 4044 - FAT_ENV_INTERFACE: 4045 4046 Define this to a string that is the name of the block device. 4047 4048 - FAT_ENV_DEVICE_AND_PART: 4049 4050 Define this to a string to specify the partition of the device. It can 4051 be as following: 4052 4053 "D:P", "D:0", "D", "D:" or "D:auto" (D, P are integers. And P >= 1) 4054 - "D:P": device D partition P. Error occurs if device D has no 4055 partition table. 4056 - "D:0": device D. 4057 - "D" or "D:": device D partition 1 if device D has partition 4058 table, or the whole device D if has no partition 4059 table. 4060 - "D:auto": first partition in device D with bootable flag set. 4061 If none, first valid partition in device D. If no 4062 partition table then means device D. 4063 4064 - FAT_ENV_FILE: 4065 4066 It's a string of the FAT file name. This file use to store the 4067 environment. 4068 4069 - CONFIG_FAT_WRITE: 4070 This should be defined. Otherwise it cannot save the environment file. 4071 4072- CONFIG_ENV_IS_IN_MMC: 4073 4074 Define this if you have an MMC device which you want to use for the 4075 environment. 4076 4077 - CONFIG_SYS_MMC_ENV_DEV: 4078 4079 Specifies which MMC device the environment is stored in. 4080 4081 - CONFIG_SYS_MMC_ENV_PART (optional): 4082 4083 Specifies which MMC partition the environment is stored in. If not 4084 set, defaults to partition 0, the user area. Common values might be 4085 1 (first MMC boot partition), 2 (second MMC boot partition). 4086 4087 - CONFIG_ENV_OFFSET: 4088 - CONFIG_ENV_SIZE: 4089 4090 These two #defines specify the offset and size of the environment 4091 area within the specified MMC device. 4092 4093 If offset is positive (the usual case), it is treated as relative to 4094 the start of the MMC partition. If offset is negative, it is treated 4095 as relative to the end of the MMC partition. This can be useful if 4096 your board may be fitted with different MMC devices, which have 4097 different sizes for the MMC partitions, and you always want the 4098 environment placed at the very end of the partition, to leave the 4099 maximum possible space before it, to store other data. 4100 4101 These two values are in units of bytes, but must be aligned to an 4102 MMC sector boundary. 4103 4104 - CONFIG_ENV_OFFSET_REDUND (optional): 4105 4106 Specifies a second storage area, of CONFIG_ENV_SIZE size, used to 4107 hold a redundant copy of the environment data. This provides a 4108 valid backup copy in case the other copy is corrupted, e.g. due 4109 to a power failure during a "saveenv" operation. 4110 4111 This value may also be positive or negative; this is handled in the 4112 same way as CONFIG_ENV_OFFSET. 4113 4114 This value is also in units of bytes, but must also be aligned to 4115 an MMC sector boundary. 4116 4117 - CONFIG_ENV_SIZE_REDUND (optional): 4118 4119 This value need not be set, even when CONFIG_ENV_OFFSET_REDUND is 4120 set. If this value is set, it must be set to the same value as 4121 CONFIG_ENV_SIZE. 4122 4123- CONFIG_SYS_SPI_INIT_OFFSET 4124 4125 Defines offset to the initial SPI buffer area in DPRAM. The 4126 area is used at an early stage (ROM part) if the environment 4127 is configured to reside in the SPI EEPROM: We need a 520 byte 4128 scratch DPRAM area. It is used between the two initialization 4129 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems 4130 to be a good choice since it makes it far enough from the 4131 start of the data area as well as from the stack pointer. 4132 4133Please note that the environment is read-only until the monitor 4134has been relocated to RAM and a RAM copy of the environment has been 4135created; also, when using EEPROM you will have to use getenv_f() 4136until then to read environment variables. 4137 4138The environment is protected by a CRC32 checksum. Before the monitor 4139is relocated into RAM, as a result of a bad CRC you will be working 4140with the compiled-in default environment - *silently*!!! [This is 4141necessary, because the first environment variable we need is the 4142"baudrate" setting for the console - if we have a bad CRC, we don't 4143have any device yet where we could complain.] 4144 4145Note: once the monitor has been relocated, then it will complain if 4146the default environment is used; a new CRC is computed as soon as you 4147use the "saveenv" command to store a valid environment. 4148 4149- CONFIG_SYS_FAULT_ECHO_LINK_DOWN: 4150 Echo the inverted Ethernet link state to the fault LED. 4151 4152 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR 4153 also needs to be defined. 4154 4155- CONFIG_SYS_FAULT_MII_ADDR: 4156 MII address of the PHY to check for the Ethernet link state. 4157 4158- CONFIG_NS16550_MIN_FUNCTIONS: 4159 Define this if you desire to only have use of the NS16550_init 4160 and NS16550_putc functions for the serial driver located at 4161 drivers/serial/ns16550.c. This option is useful for saving 4162 space for already greatly restricted images, including but not 4163 limited to NAND_SPL configurations. 4164 4165- CONFIG_DISPLAY_BOARDINFO 4166 Display information about the board that U-Boot is running on 4167 when U-Boot starts up. The board function checkboard() is called 4168 to do this. 4169 4170- CONFIG_DISPLAY_BOARDINFO_LATE 4171 Similar to the previous option, but display this information 4172 later, once stdio is running and output goes to the LCD, if 4173 present. 4174 4175- CONFIG_BOARD_SIZE_LIMIT: 4176 Maximum size of the U-Boot image. When defined, the 4177 build system checks that the actual size does not 4178 exceed it. 4179 4180Low Level (hardware related) configuration options: 4181--------------------------------------------------- 4182 4183- CONFIG_SYS_CACHELINE_SIZE: 4184 Cache Line Size of the CPU. 4185 4186- CONFIG_SYS_DEFAULT_IMMR: 4187 Default address of the IMMR after system reset. 4188 4189 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU, 4190 and RPXsuper) to be able to adjust the position of 4191 the IMMR register after a reset. 4192 4193- CONFIG_SYS_CCSRBAR_DEFAULT: 4194 Default (power-on reset) physical address of CCSR on Freescale 4195 PowerPC SOCs. 4196 4197- CONFIG_SYS_CCSRBAR: 4198 Virtual address of CCSR. On a 32-bit build, this is typically 4199 the same value as CONFIG_SYS_CCSRBAR_DEFAULT. 4200 4201 CONFIG_SYS_DEFAULT_IMMR must also be set to this value, 4202 for cross-platform code that uses that macro instead. 4203 4204- CONFIG_SYS_CCSRBAR_PHYS: 4205 Physical address of CCSR. CCSR can be relocated to a new 4206 physical address, if desired. In this case, this macro should 4207 be set to that address. Otherwise, it should be set to the 4208 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR 4209 is typically relocated on 36-bit builds. It is recommended 4210 that this macro be defined via the _HIGH and _LOW macros: 4211 4212 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH 4213 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW) 4214 4215- CONFIG_SYS_CCSRBAR_PHYS_HIGH: 4216 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically 4217 either 0 (32-bit build) or 0xF (36-bit build). This macro is 4218 used in assembly code, so it must not contain typecasts or 4219 integer size suffixes (e.g. "ULL"). 4220 4221- CONFIG_SYS_CCSRBAR_PHYS_LOW: 4222 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is 4223 used in assembly code, so it must not contain typecasts or 4224 integer size suffixes (e.g. "ULL"). 4225 4226- CONFIG_SYS_CCSR_DO_NOT_RELOCATE: 4227 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be 4228 forced to a value that ensures that CCSR is not relocated. 4229 4230- Floppy Disk Support: 4231 CONFIG_SYS_FDC_DRIVE_NUMBER 4232 4233 the default drive number (default value 0) 4234 4235 CONFIG_SYS_ISA_IO_STRIDE 4236 4237 defines the spacing between FDC chipset registers 4238 (default value 1) 4239 4240 CONFIG_SYS_ISA_IO_OFFSET 4241 4242 defines the offset of register from address. It 4243 depends on which part of the data bus is connected to 4244 the FDC chipset. (default value 0) 4245 4246 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and 4247 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their 4248 default value. 4249 4250 if CONFIG_SYS_FDC_HW_INIT is defined, then the function 4251 fdc_hw_init() is called at the beginning of the FDC 4252 setup. fdc_hw_init() must be provided by the board 4253 source code. It is used to make hardware-dependent 4254 initializations. 4255 4256- CONFIG_IDE_AHB: 4257 Most IDE controllers were designed to be connected with PCI 4258 interface. Only few of them were designed for AHB interface. 4259 When software is doing ATA command and data transfer to 4260 IDE devices through IDE-AHB controller, some additional 4261 registers accessing to these kind of IDE-AHB controller 4262 is required. 4263 4264- CONFIG_SYS_IMMR: Physical address of the Internal Memory. 4265 DO NOT CHANGE unless you know exactly what you're 4266 doing! (11-4) [MPC8xx/82xx systems only] 4267 4268- CONFIG_SYS_INIT_RAM_ADDR: 4269 4270 Start address of memory area that can be used for 4271 initial data and stack; please note that this must be 4272 writable memory that is working WITHOUT special 4273 initialization, i. e. you CANNOT use normal RAM which 4274 will become available only after programming the 4275 memory controller and running certain initialization 4276 sequences. 4277 4278 U-Boot uses the following memory types: 4279 - MPC8xx and MPC8260: IMMR (internal memory of the CPU) 4280 - MPC824X: data cache 4281 - PPC4xx: data cache 4282 4283- CONFIG_SYS_GBL_DATA_OFFSET: 4284 4285 Offset of the initial data structure in the memory 4286 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually 4287 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial 4288 data is located at the end of the available space 4289 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE - 4290 GENERATED_GBL_DATA_SIZE), and the initial stack is just 4291 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR + 4292 CONFIG_SYS_GBL_DATA_OFFSET) downward. 4293 4294 Note: 4295 On the MPC824X (or other systems that use the data 4296 cache for initial memory) the address chosen for 4297 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must 4298 point to an otherwise UNUSED address space between 4299 the top of RAM and the start of the PCI space. 4300 4301- CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6) 4302 4303- CONFIG_SYS_SYPCR: System Protection Control (11-9) 4304 4305- CONFIG_SYS_TBSCR: Time Base Status and Control (11-26) 4306 4307- CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31) 4308 4309- CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30) 4310 4311- CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27) 4312 4313- CONFIG_SYS_OR_TIMING_SDRAM: 4314 SDRAM timing 4315 4316- CONFIG_SYS_MAMR_PTA: 4317 periodic timer for refresh 4318 4319- CONFIG_SYS_DER: Debug Event Register (37-47) 4320 4321- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM, 4322 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP, 4323 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM, 4324 CONFIG_SYS_BR1_PRELIM: 4325 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH) 4326 4327- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE, 4328 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM, 4329 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM: 4330 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM) 4331 4332- CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K, 4333 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL: 4334 Machine Mode Register and Memory Periodic Timer 4335 Prescaler definitions (SDRAM timing) 4336 4337- CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]: 4338 enable I2C microcode relocation patch (MPC8xx); 4339 define relocation offset in DPRAM [DSP2] 4340 4341- CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]: 4342 enable SMC microcode relocation patch (MPC8xx); 4343 define relocation offset in DPRAM [SMC1] 4344 4345- CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]: 4346 enable SPI microcode relocation patch (MPC8xx); 4347 define relocation offset in DPRAM [SCC4] 4348 4349- CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only) 4350 Offset of the bootmode word in DPRAM used by post 4351 (Power On Self Tests). This definition overrides 4352 #define'd default value in commproc.h resp. 4353 cpm_8260.h. 4354 4355- CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB, 4356 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL, 4357 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS, 4358 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB, 4359 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START, 4360 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL, 4361 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE, 4362 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only) 4363 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set. 4364 4365- CONFIG_PCI_DISABLE_PCIE: 4366 Disable PCI-Express on systems where it is supported but not 4367 required. 4368 4369- CONFIG_PCI_ENUM_ONLY 4370 Only scan through and get the devices on the buses. 4371 Don't do any setup work, presumably because someone or 4372 something has already done it, and we don't need to do it 4373 a second time. Useful for platforms that are pre-booted 4374 by coreboot or similar. 4375 4376- CONFIG_PCI_INDIRECT_BRIDGE: 4377 Enable support for indirect PCI bridges. 4378 4379- CONFIG_SYS_SRIO: 4380 Chip has SRIO or not 4381 4382- CONFIG_SRIO1: 4383 Board has SRIO 1 port available 4384 4385- CONFIG_SRIO2: 4386 Board has SRIO 2 port available 4387 4388- CONFIG_SRIO_PCIE_BOOT_MASTER 4389 Board can support master function for Boot from SRIO and PCIE 4390 4391- CONFIG_SYS_SRIOn_MEM_VIRT: 4392 Virtual Address of SRIO port 'n' memory region 4393 4394- CONFIG_SYS_SRIOn_MEM_PHYS: 4395 Physical Address of SRIO port 'n' memory region 4396 4397- CONFIG_SYS_SRIOn_MEM_SIZE: 4398 Size of SRIO port 'n' memory region 4399 4400- CONFIG_SYS_NAND_BUSWIDTH_16BIT 4401 Defined to tell the NAND controller that the NAND chip is using 4402 a 16 bit bus. 4403 Not all NAND drivers use this symbol. 4404 Example of drivers that use it: 4405 - drivers/mtd/nand/ndfc.c 4406 - drivers/mtd/nand/mxc_nand.c 4407 4408- CONFIG_SYS_NDFC_EBC0_CFG 4409 Sets the EBC0_CFG register for the NDFC. If not defined 4410 a default value will be used. 4411 4412- CONFIG_SPD_EEPROM 4413 Get DDR timing information from an I2C EEPROM. Common 4414 with pluggable memory modules such as SODIMMs 4415 4416 SPD_EEPROM_ADDRESS 4417 I2C address of the SPD EEPROM 4418 4419- CONFIG_SYS_SPD_BUS_NUM 4420 If SPD EEPROM is on an I2C bus other than the first 4421 one, specify here. Note that the value must resolve 4422 to something your driver can deal with. 4423 4424- CONFIG_SYS_DDR_RAW_TIMING 4425 Get DDR timing information from other than SPD. Common with 4426 soldered DDR chips onboard without SPD. DDR raw timing 4427 parameters are extracted from datasheet and hard-coded into 4428 header files or board specific files. 4429 4430- CONFIG_FSL_DDR_INTERACTIVE 4431 Enable interactive DDR debugging. See doc/README.fsl-ddr. 4432 4433- CONFIG_FSL_DDR_SYNC_REFRESH 4434 Enable sync of refresh for multiple controllers. 4435 4436- CONFIG_FSL_DDR_BIST 4437 Enable built-in memory test for Freescale DDR controllers. 4438 4439- CONFIG_SYS_83XX_DDR_USES_CS0 4440 Only for 83xx systems. If specified, then DDR should 4441 be configured using CS0 and CS1 instead of CS2 and CS3. 4442 4443- CONFIG_ETHER_ON_FEC[12] 4444 Define to enable FEC[12] on a 8xx series processor. 4445 4446- CONFIG_FEC[12]_PHY 4447 Define to the hardcoded PHY address which corresponds 4448 to the given FEC; i. e. 4449 #define CONFIG_FEC1_PHY 4 4450 means that the PHY with address 4 is connected to FEC1 4451 4452 When set to -1, means to probe for first available. 4453 4454- CONFIG_FEC[12]_PHY_NORXERR 4455 The PHY does not have a RXERR line (RMII only). 4456 (so program the FEC to ignore it). 4457 4458- CONFIG_RMII 4459 Enable RMII mode for all FECs. 4460 Note that this is a global option, we can't 4461 have one FEC in standard MII mode and another in RMII mode. 4462 4463- CONFIG_CRC32_VERIFY 4464 Add a verify option to the crc32 command. 4465 The syntax is: 4466 4467 => crc32 -v <address> <count> <crc32> 4468 4469 Where address/count indicate a memory area 4470 and crc32 is the correct crc32 which the 4471 area should have. 4472 4473- CONFIG_LOOPW 4474 Add the "loopw" memory command. This only takes effect if 4475 the memory commands are activated globally (CONFIG_CMD_MEM). 4476 4477- CONFIG_MX_CYCLIC 4478 Add the "mdc" and "mwc" memory commands. These are cyclic 4479 "md/mw" commands. 4480 Examples: 4481 4482 => mdc.b 10 4 500 4483 This command will print 4 bytes (10,11,12,13) each 500 ms. 4484 4485 => mwc.l 100 12345678 10 4486 This command will write 12345678 to address 100 all 10 ms. 4487 4488 This only takes effect if the memory commands are activated 4489 globally (CONFIG_CMD_MEM). 4490 4491- CONFIG_SKIP_LOWLEVEL_INIT 4492 [ARM, NDS32, MIPS only] If this variable is defined, then certain 4493 low level initializations (like setting up the memory 4494 controller) are omitted and/or U-Boot does not 4495 relocate itself into RAM. 4496 4497 Normally this variable MUST NOT be defined. The only 4498 exception is when U-Boot is loaded (to RAM) by some 4499 other boot loader or by a debugger which performs 4500 these initializations itself. 4501 4502- CONFIG_SKIP_LOWLEVEL_INIT_ONLY 4503 [ARM926EJ-S only] This allows just the call to lowlevel_init() 4504 to be skipped. The normal CP15 init (such as enabling the 4505 instruction cache) is still performed. 4506 4507- CONFIG_SPL_BUILD 4508 Modifies the behaviour of start.S when compiling a loader 4509 that is executed before the actual U-Boot. E.g. when 4510 compiling a NAND SPL. 4511 4512- CONFIG_TPL_BUILD 4513 Modifies the behaviour of start.S when compiling a loader 4514 that is executed after the SPL and before the actual U-Boot. 4515 It is loaded by the SPL. 4516 4517- CONFIG_SYS_MPC85XX_NO_RESETVEC 4518 Only for 85xx systems. If this variable is specified, the section 4519 .resetvec is not kept and the section .bootpg is placed in the 4520 previous 4k of the .text section. 4521 4522- CONFIG_ARCH_MAP_SYSMEM 4523 Generally U-Boot (and in particular the md command) uses 4524 effective address. It is therefore not necessary to regard 4525 U-Boot address as virtual addresses that need to be translated 4526 to physical addresses. However, sandbox requires this, since 4527 it maintains its own little RAM buffer which contains all 4528 addressable memory. This option causes some memory accesses 4529 to be mapped through map_sysmem() / unmap_sysmem(). 4530 4531- CONFIG_X86_RESET_VECTOR 4532 If defined, the x86 reset vector code is included. This is not 4533 needed when U-Boot is running from Coreboot. 4534 4535- CONFIG_SYS_MPUCLK 4536 Defines the MPU clock speed (in MHz). 4537 4538 NOTE : currently only supported on AM335x platforms. 4539 4540- CONFIG_SPL_AM33XX_ENABLE_RTC32K_OSC: 4541 Enables the RTC32K OSC on AM33xx based plattforms 4542 4543- CONFIG_SYS_NAND_NO_SUBPAGE_WRITE 4544 Option to disable subpage write in NAND driver 4545 driver that uses this: 4546 drivers/mtd/nand/davinci_nand.c 4547 4548Freescale QE/FMAN Firmware Support: 4549----------------------------------- 4550 4551The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the 4552loading of "firmware", which is encoded in the QE firmware binary format. 4553This firmware often needs to be loaded during U-Boot booting, so macros 4554are used to identify the storage device (NOR flash, SPI, etc) and the address 4555within that device. 4556 4557- CONFIG_SYS_FMAN_FW_ADDR 4558 The address in the storage device where the FMAN microcode is located. The 4559 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro 4560 is also specified. 4561 4562- CONFIG_SYS_QE_FW_ADDR 4563 The address in the storage device where the QE microcode is located. The 4564 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro 4565 is also specified. 4566 4567- CONFIG_SYS_QE_FMAN_FW_LENGTH 4568 The maximum possible size of the firmware. The firmware binary format 4569 has a field that specifies the actual size of the firmware, but it 4570 might not be possible to read any part of the firmware unless some 4571 local storage is allocated to hold the entire firmware first. 4572 4573- CONFIG_SYS_QE_FMAN_FW_IN_NOR 4574 Specifies that QE/FMAN firmware is located in NOR flash, mapped as 4575 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the 4576 virtual address in NOR flash. 4577 4578- CONFIG_SYS_QE_FMAN_FW_IN_NAND 4579 Specifies that QE/FMAN firmware is located in NAND flash. 4580 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash. 4581 4582- CONFIG_SYS_QE_FMAN_FW_IN_MMC 4583 Specifies that QE/FMAN firmware is located on the primary SD/MMC 4584 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device. 4585 4586- CONFIG_SYS_QE_FMAN_FW_IN_REMOTE 4587 Specifies that QE/FMAN firmware is located in the remote (master) 4588 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which 4589 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound 4590 window->master inbound window->master LAW->the ucode address in 4591 master's memory space. 4592 4593Freescale Layerscape Management Complex Firmware Support: 4594--------------------------------------------------------- 4595The Freescale Layerscape Management Complex (MC) supports the loading of 4596"firmware". 4597This firmware often needs to be loaded during U-Boot booting, so macros 4598are used to identify the storage device (NOR flash, SPI, etc) and the address 4599within that device. 4600 4601- CONFIG_FSL_MC_ENET 4602 Enable the MC driver for Layerscape SoCs. 4603 4604Freescale Layerscape Debug Server Support: 4605------------------------------------------- 4606The Freescale Layerscape Debug Server Support supports the loading of 4607"Debug Server firmware" and triggering SP boot-rom. 4608This firmware often needs to be loaded during U-Boot booting. 4609 4610- CONFIG_SYS_MC_RSV_MEM_ALIGN 4611 Define alignment of reserved memory MC requires 4612 4613Reproducible builds 4614------------------- 4615 4616In order to achieve reproducible builds, timestamps used in the U-Boot build 4617process have to be set to a fixed value. 4618 4619This is done using the SOURCE_DATE_EPOCH environment variable. 4620SOURCE_DATE_EPOCH is to be set on the build host's shell, not as a configuration 4621option for U-Boot or an environment variable in U-Boot. 4622 4623SOURCE_DATE_EPOCH should be set to a number of seconds since the epoch, in UTC. 4624 4625Building the Software: 4626====================== 4627 4628Building U-Boot has been tested in several native build environments 4629and in many different cross environments. Of course we cannot support 4630all possibly existing versions of cross development tools in all 4631(potentially obsolete) versions. In case of tool chain problems we 4632recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK) 4633which is extensively used to build and test U-Boot. 4634 4635If you are not using a native environment, it is assumed that you 4636have GNU cross compiling tools available in your path. In this case, 4637you must set the environment variable CROSS_COMPILE in your shell. 4638Note that no changes to the Makefile or any other source files are 4639necessary. For example using the ELDK on a 4xx CPU, please enter: 4640 4641 $ CROSS_COMPILE=ppc_4xx- 4642 $ export CROSS_COMPILE 4643 4644Note: If you wish to generate Windows versions of the utilities in 4645 the tools directory you can use the MinGW toolchain 4646 (http://www.mingw.org). Set your HOST tools to the MinGW 4647 toolchain and execute 'make tools'. For example: 4648 4649 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools 4650 4651 Binaries such as tools/mkimage.exe will be created which can 4652 be executed on computers running Windows. 4653 4654U-Boot is intended to be simple to build. After installing the 4655sources you must configure U-Boot for one specific board type. This 4656is done by typing: 4657 4658 make NAME_defconfig 4659 4660where "NAME_defconfig" is the name of one of the existing configu- 4661rations; see boards.cfg for supported names. 4662 4663Note: for some board special configuration names may exist; check if 4664 additional information is available from the board vendor; for 4665 instance, the TQM823L systems are available without (standard) 4666 or with LCD support. You can select such additional "features" 4667 when choosing the configuration, i. e. 4668 4669 make TQM823L_defconfig 4670 - will configure for a plain TQM823L, i. e. no LCD support 4671 4672 make TQM823L_LCD_defconfig 4673 - will configure for a TQM823L with U-Boot console on LCD 4674 4675 etc. 4676 4677 4678Finally, type "make all", and you should get some working U-Boot 4679images ready for download to / installation on your system: 4680 4681- "u-boot.bin" is a raw binary image 4682- "u-boot" is an image in ELF binary format 4683- "u-boot.srec" is in Motorola S-Record format 4684 4685By default the build is performed locally and the objects are saved 4686in the source directory. One of the two methods can be used to change 4687this behavior and build U-Boot to some external directory: 4688 46891. Add O= to the make command line invocations: 4690 4691 make O=/tmp/build distclean 4692 make O=/tmp/build NAME_defconfig 4693 make O=/tmp/build all 4694 46952. Set environment variable KBUILD_OUTPUT to point to the desired location: 4696 4697 export KBUILD_OUTPUT=/tmp/build 4698 make distclean 4699 make NAME_defconfig 4700 make all 4701 4702Note that the command line "O=" setting overrides the KBUILD_OUTPUT environment 4703variable. 4704 4705 4706Please be aware that the Makefiles assume you are using GNU make, so 4707for instance on NetBSD you might need to use "gmake" instead of 4708native "make". 4709 4710 4711If the system board that you have is not listed, then you will need 4712to port U-Boot to your hardware platform. To do this, follow these 4713steps: 4714 47151. Create a new directory to hold your board specific code. Add any 4716 files you need. In your board directory, you will need at least 4717 the "Makefile" and a "<board>.c". 47182. Create a new configuration file "include/configs/<board>.h" for 4719 your board. 47203. If you're porting U-Boot to a new CPU, then also create a new 4721 directory to hold your CPU specific code. Add any files you need. 47224. Run "make <board>_defconfig" with your new name. 47235. Type "make", and you should get a working "u-boot.srec" file 4724 to be installed on your target system. 47256. Debug and solve any problems that might arise. 4726 [Of course, this last step is much harder than it sounds.] 4727 4728 4729Testing of U-Boot Modifications, Ports to New Hardware, etc.: 4730============================================================== 4731 4732If you have modified U-Boot sources (for instance added a new board 4733or support for new devices, a new CPU, etc.) you are expected to 4734provide feedback to the other developers. The feedback normally takes 4735the form of a "patch", i. e. a context diff against a certain (latest 4736official or latest in the git repository) version of U-Boot sources. 4737 4738But before you submit such a patch, please verify that your modifi- 4739cation did not break existing code. At least make sure that *ALL* of 4740the supported boards compile WITHOUT ANY compiler warnings. To do so, 4741just run the buildman script (tools/buildman/buildman), which will 4742configure and build U-Boot for ALL supported system. Be warned, this 4743will take a while. Please see the buildman README, or run 'buildman -H' 4744for documentation. 4745 4746 4747See also "U-Boot Porting Guide" below. 4748 4749 4750Monitor Commands - Overview: 4751============================ 4752 4753go - start application at address 'addr' 4754run - run commands in an environment variable 4755bootm - boot application image from memory 4756bootp - boot image via network using BootP/TFTP protocol 4757bootz - boot zImage from memory 4758tftpboot- boot image via network using TFTP protocol 4759 and env variables "ipaddr" and "serverip" 4760 (and eventually "gatewayip") 4761tftpput - upload a file via network using TFTP protocol 4762rarpboot- boot image via network using RARP/TFTP protocol 4763diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd' 4764loads - load S-Record file over serial line 4765loadb - load binary file over serial line (kermit mode) 4766md - memory display 4767mm - memory modify (auto-incrementing) 4768nm - memory modify (constant address) 4769mw - memory write (fill) 4770cp - memory copy 4771cmp - memory compare 4772crc32 - checksum calculation 4773i2c - I2C sub-system 4774sspi - SPI utility commands 4775base - print or set address offset 4776printenv- print environment variables 4777setenv - set environment variables 4778saveenv - save environment variables to persistent storage 4779protect - enable or disable FLASH write protection 4780erase - erase FLASH memory 4781flinfo - print FLASH memory information 4782nand - NAND memory operations (see doc/README.nand) 4783bdinfo - print Board Info structure 4784iminfo - print header information for application image 4785coninfo - print console devices and informations 4786ide - IDE sub-system 4787loop - infinite loop on address range 4788loopw - infinite write loop on address range 4789mtest - simple RAM test 4790icache - enable or disable instruction cache 4791dcache - enable or disable data cache 4792reset - Perform RESET of the CPU 4793echo - echo args to console 4794version - print monitor version 4795help - print online help 4796? - alias for 'help' 4797 4798 4799Monitor Commands - Detailed Description: 4800======================================== 4801 4802TODO. 4803 4804For now: just type "help <command>". 4805 4806 4807Environment Variables: 4808====================== 4809 4810U-Boot supports user configuration using Environment Variables which 4811can be made persistent by saving to Flash memory. 4812 4813Environment Variables are set using "setenv", printed using 4814"printenv", and saved to Flash using "saveenv". Using "setenv" 4815without a value can be used to delete a variable from the 4816environment. As long as you don't save the environment you are 4817working with an in-memory copy. In case the Flash area containing the 4818environment is erased by accident, a default environment is provided. 4819 4820Some configuration options can be set using Environment Variables. 4821 4822List of environment variables (most likely not complete): 4823 4824 baudrate - see CONFIG_BAUDRATE 4825 4826 bootdelay - see CONFIG_BOOTDELAY 4827 4828 bootcmd - see CONFIG_BOOTCOMMAND 4829 4830 bootargs - Boot arguments when booting an RTOS image 4831 4832 bootfile - Name of the image to load with TFTP 4833 4834 bootm_low - Memory range available for image processing in the bootm 4835 command can be restricted. This variable is given as 4836 a hexadecimal number and defines lowest address allowed 4837 for use by the bootm command. See also "bootm_size" 4838 environment variable. Address defined by "bootm_low" is 4839 also the base of the initial memory mapping for the Linux 4840 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and 4841 bootm_mapsize. 4842 4843 bootm_mapsize - Size of the initial memory mapping for the Linux kernel. 4844 This variable is given as a hexadecimal number and it 4845 defines the size of the memory region starting at base 4846 address bootm_low that is accessible by the Linux kernel 4847 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used 4848 as the default value if it is defined, and bootm_size is 4849 used otherwise. 4850 4851 bootm_size - Memory range available for image processing in the bootm 4852 command can be restricted. This variable is given as 4853 a hexadecimal number and defines the size of the region 4854 allowed for use by the bootm command. See also "bootm_low" 4855 environment variable. 4856 4857 updatefile - Location of the software update file on a TFTP server, used 4858 by the automatic software update feature. Please refer to 4859 documentation in doc/README.update for more details. 4860 4861 autoload - if set to "no" (any string beginning with 'n'), 4862 "bootp" will just load perform a lookup of the 4863 configuration from the BOOTP server, but not try to 4864 load any image using TFTP 4865 4866 autostart - if set to "yes", an image loaded using the "bootp", 4867 "rarpboot", "tftpboot" or "diskboot" commands will 4868 be automatically started (by internally calling 4869 "bootm") 4870 4871 If set to "no", a standalone image passed to the 4872 "bootm" command will be copied to the load address 4873 (and eventually uncompressed), but NOT be started. 4874 This can be used to load and uncompress arbitrary 4875 data. 4876 4877 fdt_high - if set this restricts the maximum address that the 4878 flattened device tree will be copied into upon boot. 4879 For example, if you have a system with 1 GB memory 4880 at physical address 0x10000000, while Linux kernel 4881 only recognizes the first 704 MB as low memory, you 4882 may need to set fdt_high as 0x3C000000 to have the 4883 device tree blob be copied to the maximum address 4884 of the 704 MB low memory, so that Linux kernel can 4885 access it during the boot procedure. 4886 4887 If this is set to the special value 0xFFFFFFFF then 4888 the fdt will not be copied at all on boot. For this 4889 to work it must reside in writable memory, have 4890 sufficient padding on the end of it for u-boot to 4891 add the information it needs into it, and the memory 4892 must be accessible by the kernel. 4893 4894 fdtcontroladdr- if set this is the address of the control flattened 4895 device tree used by U-Boot when CONFIG_OF_CONTROL is 4896 defined. 4897 4898 i2cfast - (PPC405GP|PPC405EP only) 4899 if set to 'y' configures Linux I2C driver for fast 4900 mode (400kHZ). This environment variable is used in 4901 initialization code. So, for changes to be effective 4902 it must be saved and board must be reset. 4903 4904 initrd_high - restrict positioning of initrd images: 4905 If this variable is not set, initrd images will be 4906 copied to the highest possible address in RAM; this 4907 is usually what you want since it allows for 4908 maximum initrd size. If for some reason you want to 4909 make sure that the initrd image is loaded below the 4910 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment 4911 variable to a value of "no" or "off" or "0". 4912 Alternatively, you can set it to a maximum upper 4913 address to use (U-Boot will still check that it 4914 does not overwrite the U-Boot stack and data). 4915 4916 For instance, when you have a system with 16 MB 4917 RAM, and want to reserve 4 MB from use by Linux, 4918 you can do this by adding "mem=12M" to the value of 4919 the "bootargs" variable. However, now you must make 4920 sure that the initrd image is placed in the first 4921 12 MB as well - this can be done with 4922 4923 setenv initrd_high 00c00000 4924 4925 If you set initrd_high to 0xFFFFFFFF, this is an 4926 indication to U-Boot that all addresses are legal 4927 for the Linux kernel, including addresses in flash 4928 memory. In this case U-Boot will NOT COPY the 4929 ramdisk at all. This may be useful to reduce the 4930 boot time on your system, but requires that this 4931 feature is supported by your Linux kernel. 4932 4933 ipaddr - IP address; needed for tftpboot command 4934 4935 loadaddr - Default load address for commands like "bootp", 4936 "rarpboot", "tftpboot", "loadb" or "diskboot" 4937 4938 loads_echo - see CONFIG_LOADS_ECHO 4939 4940 serverip - TFTP server IP address; needed for tftpboot command 4941 4942 bootretry - see CONFIG_BOOT_RETRY_TIME 4943 4944 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR 4945 4946 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR 4947 4948 ethprime - controls which interface is used first. 4949 4950 ethact - controls which interface is currently active. 4951 For example you can do the following 4952 4953 => setenv ethact FEC 4954 => ping 192.168.0.1 # traffic sent on FEC 4955 => setenv ethact SCC 4956 => ping 10.0.0.1 # traffic sent on SCC 4957 4958 ethrotate - When set to "no" U-Boot does not go through all 4959 available network interfaces. 4960 It just stays at the currently selected interface. 4961 4962 netretry - When set to "no" each network operation will 4963 either succeed or fail without retrying. 4964 When set to "once" the network operation will 4965 fail when all the available network interfaces 4966 are tried once without success. 4967 Useful on scripts which control the retry operation 4968 themselves. 4969 4970 npe_ucode - set load address for the NPE microcode 4971 4972 silent_linux - If set then Linux will be told to boot silently, by 4973 changing the console to be empty. If "yes" it will be 4974 made silent. If "no" it will not be made silent. If 4975 unset, then it will be made silent if the U-Boot console 4976 is silent. 4977 4978 tftpsrcp - If this is set, the value is used for TFTP's 4979 UDP source port. 4980 4981 tftpdstp - If this is set, the value is used for TFTP's UDP 4982 destination port instead of the Well Know Port 69. 4983 4984 tftpblocksize - Block size to use for TFTP transfers; if not set, 4985 we use the TFTP server's default block size 4986 4987 tftptimeout - Retransmission timeout for TFTP packets (in milli- 4988 seconds, minimum value is 1000 = 1 second). Defines 4989 when a packet is considered to be lost so it has to 4990 be retransmitted. The default is 5000 = 5 seconds. 4991 Lowering this value may make downloads succeed 4992 faster in networks with high packet loss rates or 4993 with unreliable TFTP servers. 4994 4995 tftptimeoutcountmax - maximum count of TFTP timeouts (no 4996 unit, minimum value = 0). Defines how many timeouts 4997 can happen during a single file transfer before that 4998 transfer is aborted. The default is 10, and 0 means 4999 'no timeouts allowed'. Increasing this value may help 5000 downloads succeed with high packet loss rates, or with 5001 unreliable TFTP servers or client hardware. 5002 5003 vlan - When set to a value < 4095 the traffic over 5004 Ethernet is encapsulated/received over 802.1q 5005 VLAN tagged frames. 5006 5007 bootpretryperiod - Period during which BOOTP/DHCP sends retries. 5008 Unsigned value, in milliseconds. If not set, the period will 5009 be either the default (28000), or a value based on 5010 CONFIG_NET_RETRY_COUNT, if defined. This value has 5011 precedence over the valu based on CONFIG_NET_RETRY_COUNT. 5012 5013The following image location variables contain the location of images 5014used in booting. The "Image" column gives the role of the image and is 5015not an environment variable name. The other columns are environment 5016variable names. "File Name" gives the name of the file on a TFTP 5017server, "RAM Address" gives the location in RAM the image will be 5018loaded to, and "Flash Location" gives the image's address in NOR 5019flash or offset in NAND flash. 5020 5021*Note* - these variables don't have to be defined for all boards, some 5022boards currently use other variables for these purposes, and some 5023boards use these variables for other purposes. 5024 5025Image File Name RAM Address Flash Location 5026----- --------- ----------- -------------- 5027u-boot u-boot u-boot_addr_r u-boot_addr 5028Linux kernel bootfile kernel_addr_r kernel_addr 5029device tree blob fdtfile fdt_addr_r fdt_addr 5030ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr 5031 5032The following environment variables may be used and automatically 5033updated by the network boot commands ("bootp" and "rarpboot"), 5034depending the information provided by your boot server: 5035 5036 bootfile - see above 5037 dnsip - IP address of your Domain Name Server 5038 dnsip2 - IP address of your secondary Domain Name Server 5039 gatewayip - IP address of the Gateway (Router) to use 5040 hostname - Target hostname 5041 ipaddr - see above 5042 netmask - Subnet Mask 5043 rootpath - Pathname of the root filesystem on the NFS server 5044 serverip - see above 5045 5046 5047There are two special Environment Variables: 5048 5049 serial# - contains hardware identification information such 5050 as type string and/or serial number 5051 ethaddr - Ethernet address 5052 5053These variables can be set only once (usually during manufacturing of 5054the board). U-Boot refuses to delete or overwrite these variables 5055once they have been set once. 5056 5057 5058Further special Environment Variables: 5059 5060 ver - Contains the U-Boot version string as printed 5061 with the "version" command. This variable is 5062 readonly (see CONFIG_VERSION_VARIABLE). 5063 5064 5065Please note that changes to some configuration parameters may take 5066only effect after the next boot (yes, that's just like Windoze :-). 5067 5068 5069Callback functions for environment variables: 5070--------------------------------------------- 5071 5072For some environment variables, the behavior of u-boot needs to change 5073when their values are changed. This functionality allows functions to 5074be associated with arbitrary variables. On creation, overwrite, or 5075deletion, the callback will provide the opportunity for some side 5076effect to happen or for the change to be rejected. 5077 5078The callbacks are named and associated with a function using the 5079U_BOOT_ENV_CALLBACK macro in your board or driver code. 5080 5081These callbacks are associated with variables in one of two ways. The 5082static list can be added to by defining CONFIG_ENV_CALLBACK_LIST_STATIC 5083in the board configuration to a string that defines a list of 5084associations. The list must be in the following format: 5085 5086 entry = variable_name[:callback_name] 5087 list = entry[,list] 5088 5089If the callback name is not specified, then the callback is deleted. 5090Spaces are also allowed anywhere in the list. 5091 5092Callbacks can also be associated by defining the ".callbacks" variable 5093with the same list format above. Any association in ".callbacks" will 5094override any association in the static list. You can define 5095CONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the 5096".callbacks" environment variable in the default or embedded environment. 5097 5098If CONFIG_REGEX is defined, the variable_name above is evaluated as a 5099regular expression. This allows multiple variables to be connected to 5100the same callback without explicitly listing them all out. 5101 5102 5103Command Line Parsing: 5104===================== 5105 5106There are two different command line parsers available with U-Boot: 5107the old "simple" one, and the much more powerful "hush" shell: 5108 5109Old, simple command line parser: 5110-------------------------------- 5111 5112- supports environment variables (through setenv / saveenv commands) 5113- several commands on one line, separated by ';' 5114- variable substitution using "... ${name} ..." syntax 5115- special characters ('$', ';') can be escaped by prefixing with '\', 5116 for example: 5117 setenv bootcmd bootm \${address} 5118- You can also escape text by enclosing in single apostrophes, for example: 5119 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off' 5120 5121Hush shell: 5122----------- 5123 5124- similar to Bourne shell, with control structures like 5125 if...then...else...fi, for...do...done; while...do...done, 5126 until...do...done, ... 5127- supports environment ("global") variables (through setenv / saveenv 5128 commands) and local shell variables (through standard shell syntax 5129 "name=value"); only environment variables can be used with "run" 5130 command 5131 5132General rules: 5133-------------- 5134 5135(1) If a command line (or an environment variable executed by a "run" 5136 command) contains several commands separated by semicolon, and 5137 one of these commands fails, then the remaining commands will be 5138 executed anyway. 5139 5140(2) If you execute several variables with one call to run (i. e. 5141 calling run with a list of variables as arguments), any failing 5142 command will cause "run" to terminate, i. e. the remaining 5143 variables are not executed. 5144 5145Note for Redundant Ethernet Interfaces: 5146======================================= 5147 5148Some boards come with redundant Ethernet interfaces; U-Boot supports 5149such configurations and is capable of automatic selection of a 5150"working" interface when needed. MAC assignment works as follows: 5151 5152Network interfaces are numbered eth0, eth1, eth2, ... Corresponding 5153MAC addresses can be stored in the environment as "ethaddr" (=>eth0), 5154"eth1addr" (=>eth1), "eth2addr", ... 5155 5156If the network interface stores some valid MAC address (for instance 5157in SROM), this is used as default address if there is NO correspon- 5158ding setting in the environment; if the corresponding environment 5159variable is set, this overrides the settings in the card; that means: 5160 5161o If the SROM has a valid MAC address, and there is no address in the 5162 environment, the SROM's address is used. 5163 5164o If there is no valid address in the SROM, and a definition in the 5165 environment exists, then the value from the environment variable is 5166 used. 5167 5168o If both the SROM and the environment contain a MAC address, and 5169 both addresses are the same, this MAC address is used. 5170 5171o If both the SROM and the environment contain a MAC address, and the 5172 addresses differ, the value from the environment is used and a 5173 warning is printed. 5174 5175o If neither SROM nor the environment contain a MAC address, an error 5176 is raised. If CONFIG_NET_RANDOM_ETHADDR is defined, then in this case 5177 a random, locally-assigned MAC is used. 5178 5179If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses 5180will be programmed into hardware as part of the initialization process. This 5181may be skipped by setting the appropriate 'ethmacskip' environment variable. 5182The naming convention is as follows: 5183"ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc. 5184 5185Image Formats: 5186============== 5187 5188U-Boot is capable of booting (and performing other auxiliary operations on) 5189images in two formats: 5190 5191New uImage format (FIT) 5192----------------------- 5193 5194Flexible and powerful format based on Flattened Image Tree -- FIT (similar 5195to Flattened Device Tree). It allows the use of images with multiple 5196components (several kernels, ramdisks, etc.), with contents protected by 5197SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory. 5198 5199 5200Old uImage format 5201----------------- 5202 5203Old image format is based on binary files which can be basically anything, 5204preceded by a special header; see the definitions in include/image.h for 5205details; basically, the header defines the following image properties: 5206 5207* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD, 5208 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks, 5209 LynxOS, pSOS, QNX, RTEMS, INTEGRITY; 5210 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS, 5211 INTEGRITY). 5212* Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86, 5213 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit; 5214 Currently supported: ARM, AVR32, Intel x86, MIPS, NDS32, Nios II, PowerPC). 5215* Compression Type (uncompressed, gzip, bzip2) 5216* Load Address 5217* Entry Point 5218* Image Name 5219* Image Timestamp 5220 5221The header is marked by a special Magic Number, and both the header 5222and the data portions of the image are secured against corruption by 5223CRC32 checksums. 5224 5225 5226Linux Support: 5227============== 5228 5229Although U-Boot should support any OS or standalone application 5230easily, the main focus has always been on Linux during the design of 5231U-Boot. 5232 5233U-Boot includes many features that so far have been part of some 5234special "boot loader" code within the Linux kernel. Also, any 5235"initrd" images to be used are no longer part of one big Linux image; 5236instead, kernel and "initrd" are separate images. This implementation 5237serves several purposes: 5238 5239- the same features can be used for other OS or standalone 5240 applications (for instance: using compressed images to reduce the 5241 Flash memory footprint) 5242 5243- it becomes much easier to port new Linux kernel versions because 5244 lots of low-level, hardware dependent stuff are done by U-Boot 5245 5246- the same Linux kernel image can now be used with different "initrd" 5247 images; of course this also means that different kernel images can 5248 be run with the same "initrd". This makes testing easier (you don't 5249 have to build a new "zImage.initrd" Linux image when you just 5250 change a file in your "initrd"). Also, a field-upgrade of the 5251 software is easier now. 5252 5253 5254Linux HOWTO: 5255============ 5256 5257Porting Linux to U-Boot based systems: 5258--------------------------------------- 5259 5260U-Boot cannot save you from doing all the necessary modifications to 5261configure the Linux device drivers for use with your target hardware 5262(no, we don't intend to provide a full virtual machine interface to 5263Linux :-). 5264 5265But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot). 5266 5267Just make sure your machine specific header file (for instance 5268include/asm-ppc/tqm8xx.h) includes the same definition of the Board 5269Information structure as we define in include/asm-<arch>/u-boot.h, 5270and make sure that your definition of IMAP_ADDR uses the same value 5271as your U-Boot configuration in CONFIG_SYS_IMMR. 5272 5273Note that U-Boot now has a driver model, a unified model for drivers. 5274If you are adding a new driver, plumb it into driver model. If there 5275is no uclass available, you are encouraged to create one. See 5276doc/driver-model. 5277 5278 5279Configuring the Linux kernel: 5280----------------------------- 5281 5282No specific requirements for U-Boot. Make sure you have some root 5283device (initial ramdisk, NFS) for your target system. 5284 5285 5286Building a Linux Image: 5287----------------------- 5288 5289With U-Boot, "normal" build targets like "zImage" or "bzImage" are 5290not used. If you use recent kernel source, a new build target 5291"uImage" will exist which automatically builds an image usable by 5292U-Boot. Most older kernels also have support for a "pImage" target, 5293which was introduced for our predecessor project PPCBoot and uses a 5294100% compatible format. 5295 5296Example: 5297 5298 make TQM850L_defconfig 5299 make oldconfig 5300 make dep 5301 make uImage 5302 5303The "uImage" build target uses a special tool (in 'tools/mkimage') to 5304encapsulate a compressed Linux kernel image with header information, 5305CRC32 checksum etc. for use with U-Boot. This is what we are doing: 5306 5307* build a standard "vmlinux" kernel image (in ELF binary format): 5308 5309* convert the kernel into a raw binary image: 5310 5311 ${CROSS_COMPILE}-objcopy -O binary \ 5312 -R .note -R .comment \ 5313 -S vmlinux linux.bin 5314 5315* compress the binary image: 5316 5317 gzip -9 linux.bin 5318 5319* package compressed binary image for U-Boot: 5320 5321 mkimage -A ppc -O linux -T kernel -C gzip \ 5322 -a 0 -e 0 -n "Linux Kernel Image" \ 5323 -d linux.bin.gz uImage 5324 5325 5326The "mkimage" tool can also be used to create ramdisk images for use 5327with U-Boot, either separated from the Linux kernel image, or 5328combined into one file. "mkimage" encapsulates the images with a 64 5329byte header containing information about target architecture, 5330operating system, image type, compression method, entry points, time 5331stamp, CRC32 checksums, etc. 5332 5333"mkimage" can be called in two ways: to verify existing images and 5334print the header information, or to build new images. 5335 5336In the first form (with "-l" option) mkimage lists the information 5337contained in the header of an existing U-Boot image; this includes 5338checksum verification: 5339 5340 tools/mkimage -l image 5341 -l ==> list image header information 5342 5343The second form (with "-d" option) is used to build a U-Boot image 5344from a "data file" which is used as image payload: 5345 5346 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \ 5347 -n name -d data_file image 5348 -A ==> set architecture to 'arch' 5349 -O ==> set operating system to 'os' 5350 -T ==> set image type to 'type' 5351 -C ==> set compression type 'comp' 5352 -a ==> set load address to 'addr' (hex) 5353 -e ==> set entry point to 'ep' (hex) 5354 -n ==> set image name to 'name' 5355 -d ==> use image data from 'datafile' 5356 5357Right now, all Linux kernels for PowerPC systems use the same load 5358address (0x00000000), but the entry point address depends on the 5359kernel version: 5360 5361- 2.2.x kernels have the entry point at 0x0000000C, 5362- 2.3.x and later kernels have the entry point at 0x00000000. 5363 5364So a typical call to build a U-Boot image would read: 5365 5366 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 5367 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \ 5368 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \ 5369 > examples/uImage.TQM850L 5370 Image Name: 2.4.4 kernel for TQM850L 5371 Created: Wed Jul 19 02:34:59 2000 5372 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5373 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 5374 Load Address: 0x00000000 5375 Entry Point: 0x00000000 5376 5377To verify the contents of the image (or check for corruption): 5378 5379 -> tools/mkimage -l examples/uImage.TQM850L 5380 Image Name: 2.4.4 kernel for TQM850L 5381 Created: Wed Jul 19 02:34:59 2000 5382 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5383 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 5384 Load Address: 0x00000000 5385 Entry Point: 0x00000000 5386 5387NOTE: for embedded systems where boot time is critical you can trade 5388speed for memory and install an UNCOMPRESSED image instead: this 5389needs more space in Flash, but boots much faster since it does not 5390need to be uncompressed: 5391 5392 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz 5393 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 5394 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \ 5395 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \ 5396 > examples/uImage.TQM850L-uncompressed 5397 Image Name: 2.4.4 kernel for TQM850L 5398 Created: Wed Jul 19 02:34:59 2000 5399 Image Type: PowerPC Linux Kernel Image (uncompressed) 5400 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB 5401 Load Address: 0x00000000 5402 Entry Point: 0x00000000 5403 5404 5405Similar you can build U-Boot images from a 'ramdisk.image.gz' file 5406when your kernel is intended to use an initial ramdisk: 5407 5408 -> tools/mkimage -n 'Simple Ramdisk Image' \ 5409 > -A ppc -O linux -T ramdisk -C gzip \ 5410 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd 5411 Image Name: Simple Ramdisk Image 5412 Created: Wed Jan 12 14:01:50 2000 5413 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 5414 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB 5415 Load Address: 0x00000000 5416 Entry Point: 0x00000000 5417 5418The "dumpimage" is a tool to disassemble images built by mkimage. Its "-i" 5419option performs the converse operation of the mkimage's second form (the "-d" 5420option). Given an image built by mkimage, the dumpimage extracts a "data file" 5421from the image: 5422 5423 tools/dumpimage -i image -T type -p position data_file 5424 -i ==> extract from the 'image' a specific 'data_file' 5425 -T ==> set image type to 'type' 5426 -p ==> 'position' (starting at 0) of the 'data_file' inside the 'image' 5427 5428 5429Installing a Linux Image: 5430------------------------- 5431 5432To downloading a U-Boot image over the serial (console) interface, 5433you must convert the image to S-Record format: 5434 5435 objcopy -I binary -O srec examples/image examples/image.srec 5436 5437The 'objcopy' does not understand the information in the U-Boot 5438image header, so the resulting S-Record file will be relative to 5439address 0x00000000. To load it to a given address, you need to 5440specify the target address as 'offset' parameter with the 'loads' 5441command. 5442 5443Example: install the image to address 0x40100000 (which on the 5444TQM8xxL is in the first Flash bank): 5445 5446 => erase 40100000 401FFFFF 5447 5448 .......... done 5449 Erased 8 sectors 5450 5451 => loads 40100000 5452 ## Ready for S-Record download ... 5453 ~>examples/image.srec 5454 1 2 3 4 5 6 7 8 9 10 11 12 13 ... 5455 ... 5456 15989 15990 15991 15992 5457 [file transfer complete] 5458 [connected] 5459 ## Start Addr = 0x00000000 5460 5461 5462You can check the success of the download using the 'iminfo' command; 5463this includes a checksum verification so you can be sure no data 5464corruption happened: 5465 5466 => imi 40100000 5467 5468 ## Checking Image at 40100000 ... 5469 Image Name: 2.2.13 for initrd on TQM850L 5470 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5471 Data Size: 335725 Bytes = 327 kB = 0 MB 5472 Load Address: 00000000 5473 Entry Point: 0000000c 5474 Verifying Checksum ... OK 5475 5476 5477Boot Linux: 5478----------- 5479 5480The "bootm" command is used to boot an application that is stored in 5481memory (RAM or Flash). In case of a Linux kernel image, the contents 5482of the "bootargs" environment variable is passed to the kernel as 5483parameters. You can check and modify this variable using the 5484"printenv" and "setenv" commands: 5485 5486 5487 => printenv bootargs 5488 bootargs=root=/dev/ram 5489 5490 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5491 5492 => printenv bootargs 5493 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5494 5495 => bootm 40020000 5496 ## Booting Linux kernel at 40020000 ... 5497 Image Name: 2.2.13 for NFS on TQM850L 5498 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5499 Data Size: 381681 Bytes = 372 kB = 0 MB 5500 Load Address: 00000000 5501 Entry Point: 0000000c 5502 Verifying Checksum ... OK 5503 Uncompressing Kernel Image ... OK 5504 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 5505 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5506 time_init: decrementer frequency = 187500000/60 5507 Calibrating delay loop... 49.77 BogoMIPS 5508 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000] 5509 ... 5510 5511If you want to boot a Linux kernel with initial RAM disk, you pass 5512the memory addresses of both the kernel and the initrd image (PPBCOOT 5513format!) to the "bootm" command: 5514 5515 => imi 40100000 40200000 5516 5517 ## Checking Image at 40100000 ... 5518 Image Name: 2.2.13 for initrd on TQM850L 5519 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5520 Data Size: 335725 Bytes = 327 kB = 0 MB 5521 Load Address: 00000000 5522 Entry Point: 0000000c 5523 Verifying Checksum ... OK 5524 5525 ## Checking Image at 40200000 ... 5526 Image Name: Simple Ramdisk Image 5527 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 5528 Data Size: 566530 Bytes = 553 kB = 0 MB 5529 Load Address: 00000000 5530 Entry Point: 00000000 5531 Verifying Checksum ... OK 5532 5533 => bootm 40100000 40200000 5534 ## Booting Linux kernel at 40100000 ... 5535 Image Name: 2.2.13 for initrd on TQM850L 5536 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5537 Data Size: 335725 Bytes = 327 kB = 0 MB 5538 Load Address: 00000000 5539 Entry Point: 0000000c 5540 Verifying Checksum ... OK 5541 Uncompressing Kernel Image ... OK 5542 ## Loading RAMDisk Image at 40200000 ... 5543 Image Name: Simple Ramdisk Image 5544 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 5545 Data Size: 566530 Bytes = 553 kB = 0 MB 5546 Load Address: 00000000 5547 Entry Point: 00000000 5548 Verifying Checksum ... OK 5549 Loading Ramdisk ... OK 5550 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 5551 Boot arguments: root=/dev/ram 5552 time_init: decrementer frequency = 187500000/60 5553 Calibrating delay loop... 49.77 BogoMIPS 5554 ... 5555 RAMDISK: Compressed image found at block 0 5556 VFS: Mounted root (ext2 filesystem). 5557 5558 bash# 5559 5560Boot Linux and pass a flat device tree: 5561----------- 5562 5563First, U-Boot must be compiled with the appropriate defines. See the section 5564titled "Linux Kernel Interface" above for a more in depth explanation. The 5565following is an example of how to start a kernel and pass an updated 5566flat device tree: 5567 5568=> print oftaddr 5569oftaddr=0x300000 5570=> print oft 5571oft=oftrees/mpc8540ads.dtb 5572=> tftp $oftaddr $oft 5573Speed: 1000, full duplex 5574Using TSEC0 device 5575TFTP from server 192.168.1.1; our IP address is 192.168.1.101 5576Filename 'oftrees/mpc8540ads.dtb'. 5577Load address: 0x300000 5578Loading: # 5579done 5580Bytes transferred = 4106 (100a hex) 5581=> tftp $loadaddr $bootfile 5582Speed: 1000, full duplex 5583Using TSEC0 device 5584TFTP from server 192.168.1.1; our IP address is 192.168.1.2 5585Filename 'uImage'. 5586Load address: 0x200000 5587Loading:############ 5588done 5589Bytes transferred = 1029407 (fb51f hex) 5590=> print loadaddr 5591loadaddr=200000 5592=> print oftaddr 5593oftaddr=0x300000 5594=> bootm $loadaddr - $oftaddr 5595## Booting image at 00200000 ... 5596 Image Name: Linux-2.6.17-dirty 5597 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5598 Data Size: 1029343 Bytes = 1005.2 kB 5599 Load Address: 00000000 5600 Entry Point: 00000000 5601 Verifying Checksum ... OK 5602 Uncompressing Kernel Image ... OK 5603Booting using flat device tree at 0x300000 5604Using MPC85xx ADS machine description 5605Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb 5606[snip] 5607 5608 5609More About U-Boot Image Types: 5610------------------------------ 5611 5612U-Boot supports the following image types: 5613 5614 "Standalone Programs" are directly runnable in the environment 5615 provided by U-Boot; it is expected that (if they behave 5616 well) you can continue to work in U-Boot after return from 5617 the Standalone Program. 5618 "OS Kernel Images" are usually images of some Embedded OS which 5619 will take over control completely. Usually these programs 5620 will install their own set of exception handlers, device 5621 drivers, set up the MMU, etc. - this means, that you cannot 5622 expect to re-enter U-Boot except by resetting the CPU. 5623 "RAMDisk Images" are more or less just data blocks, and their 5624 parameters (address, size) are passed to an OS kernel that is 5625 being started. 5626 "Multi-File Images" contain several images, typically an OS 5627 (Linux) kernel image and one or more data images like 5628 RAMDisks. This construct is useful for instance when you want 5629 to boot over the network using BOOTP etc., where the boot 5630 server provides just a single image file, but you want to get 5631 for instance an OS kernel and a RAMDisk image. 5632 5633 "Multi-File Images" start with a list of image sizes, each 5634 image size (in bytes) specified by an "uint32_t" in network 5635 byte order. This list is terminated by an "(uint32_t)0". 5636 Immediately after the terminating 0 follow the images, one by 5637 one, all aligned on "uint32_t" boundaries (size rounded up to 5638 a multiple of 4 bytes). 5639 5640 "Firmware Images" are binary images containing firmware (like 5641 U-Boot or FPGA images) which usually will be programmed to 5642 flash memory. 5643 5644 "Script files" are command sequences that will be executed by 5645 U-Boot's command interpreter; this feature is especially 5646 useful when you configure U-Boot to use a real shell (hush) 5647 as command interpreter. 5648 5649Booting the Linux zImage: 5650------------------------- 5651 5652On some platforms, it's possible to boot Linux zImage. This is done 5653using the "bootz" command. The syntax of "bootz" command is the same 5654as the syntax of "bootm" command. 5655 5656Note, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply 5657kernel with raw initrd images. The syntax is slightly different, the 5658address of the initrd must be augmented by it's size, in the following 5659format: "<initrd addres>:<initrd size>". 5660 5661 5662Standalone HOWTO: 5663================= 5664 5665One of the features of U-Boot is that you can dynamically load and 5666run "standalone" applications, which can use some resources of 5667U-Boot like console I/O functions or interrupt services. 5668 5669Two simple examples are included with the sources: 5670 5671"Hello World" Demo: 5672------------------- 5673 5674'examples/hello_world.c' contains a small "Hello World" Demo 5675application; it is automatically compiled when you build U-Boot. 5676It's configured to run at address 0x00040004, so you can play with it 5677like that: 5678 5679 => loads 5680 ## Ready for S-Record download ... 5681 ~>examples/hello_world.srec 5682 1 2 3 4 5 6 7 8 9 10 11 ... 5683 [file transfer complete] 5684 [connected] 5685 ## Start Addr = 0x00040004 5686 5687 => go 40004 Hello World! This is a test. 5688 ## Starting application at 0x00040004 ... 5689 Hello World 5690 argc = 7 5691 argv[0] = "40004" 5692 argv[1] = "Hello" 5693 argv[2] = "World!" 5694 argv[3] = "This" 5695 argv[4] = "is" 5696 argv[5] = "a" 5697 argv[6] = "test." 5698 argv[7] = "<NULL>" 5699 Hit any key to exit ... 5700 5701 ## Application terminated, rc = 0x0 5702 5703Another example, which demonstrates how to register a CPM interrupt 5704handler with the U-Boot code, can be found in 'examples/timer.c'. 5705Here, a CPM timer is set up to generate an interrupt every second. 5706The interrupt service routine is trivial, just printing a '.' 5707character, but this is just a demo program. The application can be 5708controlled by the following keys: 5709 5710 ? - print current values og the CPM Timer registers 5711 b - enable interrupts and start timer 5712 e - stop timer and disable interrupts 5713 q - quit application 5714 5715 => loads 5716 ## Ready for S-Record download ... 5717 ~>examples/timer.srec 5718 1 2 3 4 5 6 7 8 9 10 11 ... 5719 [file transfer complete] 5720 [connected] 5721 ## Start Addr = 0x00040004 5722 5723 => go 40004 5724 ## Starting application at 0x00040004 ... 5725 TIMERS=0xfff00980 5726 Using timer 1 5727 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0 5728 5729Hit 'b': 5730 [q, b, e, ?] Set interval 1000000 us 5731 Enabling timer 5732Hit '?': 5733 [q, b, e, ?] ........ 5734 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0 5735Hit '?': 5736 [q, b, e, ?] . 5737 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0 5738Hit '?': 5739 [q, b, e, ?] . 5740 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0 5741Hit '?': 5742 [q, b, e, ?] . 5743 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0 5744Hit 'e': 5745 [q, b, e, ?] ...Stopping timer 5746Hit 'q': 5747 [q, b, e, ?] ## Application terminated, rc = 0x0 5748 5749 5750Minicom warning: 5751================ 5752 5753Over time, many people have reported problems when trying to use the 5754"minicom" terminal emulation program for serial download. I (wd) 5755consider minicom to be broken, and recommend not to use it. Under 5756Unix, I recommend to use C-Kermit for general purpose use (and 5757especially for kermit binary protocol download ("loadb" command), and 5758use "cu" for S-Record download ("loads" command). See 5759http://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3. 5760for help with kermit. 5761 5762 5763Nevertheless, if you absolutely want to use it try adding this 5764configuration to your "File transfer protocols" section: 5765 5766 Name Program Name U/D FullScr IO-Red. Multi 5767 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N 5768 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N 5769 5770 5771NetBSD Notes: 5772============= 5773 5774Starting at version 0.9.2, U-Boot supports NetBSD both as host 5775(build U-Boot) and target system (boots NetBSD/mpc8xx). 5776 5777Building requires a cross environment; it is known to work on 5778NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also 5779need gmake since the Makefiles are not compatible with BSD make). 5780Note that the cross-powerpc package does not install include files; 5781attempting to build U-Boot will fail because <machine/ansi.h> is 5782missing. This file has to be installed and patched manually: 5783 5784 # cd /usr/pkg/cross/powerpc-netbsd/include 5785 # mkdir powerpc 5786 # ln -s powerpc machine 5787 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h 5788 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST 5789 5790Native builds *don't* work due to incompatibilities between native 5791and U-Boot include files. 5792 5793Booting assumes that (the first part of) the image booted is a 5794stage-2 loader which in turn loads and then invokes the kernel 5795proper. Loader sources will eventually appear in the NetBSD source 5796tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the 5797meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz 5798 5799 5800Implementation Internals: 5801========================= 5802 5803The following is not intended to be a complete description of every 5804implementation detail. However, it should help to understand the 5805inner workings of U-Boot and make it easier to port it to custom 5806hardware. 5807 5808 5809Initial Stack, Global Data: 5810--------------------------- 5811 5812The implementation of U-Boot is complicated by the fact that U-Boot 5813starts running out of ROM (flash memory), usually without access to 5814system RAM (because the memory controller is not initialized yet). 5815This means that we don't have writable Data or BSS segments, and BSS 5816is not initialized as zero. To be able to get a C environment working 5817at all, we have to allocate at least a minimal stack. Implementation 5818options for this are defined and restricted by the CPU used: Some CPU 5819models provide on-chip memory (like the IMMR area on MPC8xx and 5820MPC826x processors), on others (parts of) the data cache can be 5821locked as (mis-) used as memory, etc. 5822 5823 Chris Hallinan posted a good summary of these issues to the 5824 U-Boot mailing list: 5825 5826 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)? 5827 From: "Chris Hallinan" <clh@net1plus.com> 5828 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET) 5829 ... 5830 5831 Correct me if I'm wrong, folks, but the way I understand it 5832 is this: Using DCACHE as initial RAM for Stack, etc, does not 5833 require any physical RAM backing up the cache. The cleverness 5834 is that the cache is being used as a temporary supply of 5835 necessary storage before the SDRAM controller is setup. It's 5836 beyond the scope of this list to explain the details, but you 5837 can see how this works by studying the cache architecture and 5838 operation in the architecture and processor-specific manuals. 5839 5840 OCM is On Chip Memory, which I believe the 405GP has 4K. It 5841 is another option for the system designer to use as an 5842 initial stack/RAM area prior to SDRAM being available. Either 5843 option should work for you. Using CS 4 should be fine if your 5844 board designers haven't used it for something that would 5845 cause you grief during the initial boot! It is frequently not 5846 used. 5847 5848 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere 5849 with your processor/board/system design. The default value 5850 you will find in any recent u-boot distribution in 5851 walnut.h should work for you. I'd set it to a value larger 5852 than your SDRAM module. If you have a 64MB SDRAM module, set 5853 it above 400_0000. Just make sure your board has no resources 5854 that are supposed to respond to that address! That code in 5855 start.S has been around a while and should work as is when 5856 you get the config right. 5857 5858 -Chris Hallinan 5859 DS4.COM, Inc. 5860 5861It is essential to remember this, since it has some impact on the C 5862code for the initialization procedures: 5863 5864* Initialized global data (data segment) is read-only. Do not attempt 5865 to write it. 5866 5867* Do not use any uninitialized global data (or implicitly initialized 5868 as zero data - BSS segment) at all - this is undefined, initiali- 5869 zation is performed later (when relocating to RAM). 5870 5871* Stack space is very limited. Avoid big data buffers or things like 5872 that. 5873 5874Having only the stack as writable memory limits means we cannot use 5875normal global data to share information between the code. But it 5876turned out that the implementation of U-Boot can be greatly 5877simplified by making a global data structure (gd_t) available to all 5878functions. We could pass a pointer to this data as argument to _all_ 5879functions, but this would bloat the code. Instead we use a feature of 5880the GCC compiler (Global Register Variables) to share the data: we 5881place a pointer (gd) to the global data into a register which we 5882reserve for this purpose. 5883 5884When choosing a register for such a purpose we are restricted by the 5885relevant (E)ABI specifications for the current architecture, and by 5886GCC's implementation. 5887 5888For PowerPC, the following registers have specific use: 5889 R1: stack pointer 5890 R2: reserved for system use 5891 R3-R4: parameter passing and return values 5892 R5-R10: parameter passing 5893 R13: small data area pointer 5894 R30: GOT pointer 5895 R31: frame pointer 5896 5897 (U-Boot also uses R12 as internal GOT pointer. r12 5898 is a volatile register so r12 needs to be reset when 5899 going back and forth between asm and C) 5900 5901 ==> U-Boot will use R2 to hold a pointer to the global data 5902 5903 Note: on PPC, we could use a static initializer (since the 5904 address of the global data structure is known at compile time), 5905 but it turned out that reserving a register results in somewhat 5906 smaller code - although the code savings are not that big (on 5907 average for all boards 752 bytes for the whole U-Boot image, 5908 624 text + 127 data). 5909 5910On ARM, the following registers are used: 5911 5912 R0: function argument word/integer result 5913 R1-R3: function argument word 5914 R9: platform specific 5915 R10: stack limit (used only if stack checking is enabled) 5916 R11: argument (frame) pointer 5917 R12: temporary workspace 5918 R13: stack pointer 5919 R14: link register 5920 R15: program counter 5921 5922 ==> U-Boot will use R9 to hold a pointer to the global data 5923 5924 Note: on ARM, only R_ARM_RELATIVE relocations are supported. 5925 5926On Nios II, the ABI is documented here: 5927 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf 5928 5929 ==> U-Boot will use gp to hold a pointer to the global data 5930 5931 Note: on Nios II, we give "-G0" option to gcc and don't use gp 5932 to access small data sections, so gp is free. 5933 5934On NDS32, the following registers are used: 5935 5936 R0-R1: argument/return 5937 R2-R5: argument 5938 R15: temporary register for assembler 5939 R16: trampoline register 5940 R28: frame pointer (FP) 5941 R29: global pointer (GP) 5942 R30: link register (LP) 5943 R31: stack pointer (SP) 5944 PC: program counter (PC) 5945 5946 ==> U-Boot will use R10 to hold a pointer to the global data 5947 5948NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope, 5949or current versions of GCC may "optimize" the code too much. 5950 5951Memory Management: 5952------------------ 5953 5954U-Boot runs in system state and uses physical addresses, i.e. the 5955MMU is not used either for address mapping nor for memory protection. 5956 5957The available memory is mapped to fixed addresses using the memory 5958controller. In this process, a contiguous block is formed for each 5959memory type (Flash, SDRAM, SRAM), even when it consists of several 5960physical memory banks. 5961 5962U-Boot is installed in the first 128 kB of the first Flash bank (on 5963TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After 5964booting and sizing and initializing DRAM, the code relocates itself 5965to the upper end of DRAM. Immediately below the U-Boot code some 5966memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN 5967configuration setting]. Below that, a structure with global Board 5968Info data is placed, followed by the stack (growing downward). 5969 5970Additionally, some exception handler code is copied to the low 8 kB 5971of DRAM (0x00000000 ... 0x00001FFF). 5972 5973So a typical memory configuration with 16 MB of DRAM could look like 5974this: 5975 5976 0x0000 0000 Exception Vector code 5977 : 5978 0x0000 1FFF 5979 0x0000 2000 Free for Application Use 5980 : 5981 : 5982 5983 : 5984 : 5985 0x00FB FF20 Monitor Stack (Growing downward) 5986 0x00FB FFAC Board Info Data and permanent copy of global data 5987 0x00FC 0000 Malloc Arena 5988 : 5989 0x00FD FFFF 5990 0x00FE 0000 RAM Copy of Monitor Code 5991 ... eventually: LCD or video framebuffer 5992 ... eventually: pRAM (Protected RAM - unchanged by reset) 5993 0x00FF FFFF [End of RAM] 5994 5995 5996System Initialization: 5997---------------------- 5998 5999In the reset configuration, U-Boot starts at the reset entry point 6000(on most PowerPC systems at address 0x00000100). Because of the reset 6001configuration for CS0# this is a mirror of the on board Flash memory. 6002To be able to re-map memory U-Boot then jumps to its link address. 6003To be able to implement the initialization code in C, a (small!) 6004initial stack is set up in the internal Dual Ported RAM (in case CPUs 6005which provide such a feature like MPC8xx or MPC8260), or in a locked 6006part of the data cache. After that, U-Boot initializes the CPU core, 6007the caches and the SIU. 6008 6009Next, all (potentially) available memory banks are mapped using a 6010preliminary mapping. For example, we put them on 512 MB boundaries 6011(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash 6012on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is 6013programmed for SDRAM access. Using the temporary configuration, a 6014simple memory test is run that determines the size of the SDRAM 6015banks. 6016 6017When there is more than one SDRAM bank, and the banks are of 6018different size, the largest is mapped first. For equal size, the first 6019bank (CS2#) is mapped first. The first mapping is always for address 60200x00000000, with any additional banks following immediately to create 6021contiguous memory starting from 0. 6022 6023Then, the monitor installs itself at the upper end of the SDRAM area 6024and allocates memory for use by malloc() and for the global Board 6025Info data; also, the exception vector code is copied to the low RAM 6026pages, and the final stack is set up. 6027 6028Only after this relocation will you have a "normal" C environment; 6029until that you are restricted in several ways, mostly because you are 6030running from ROM, and because the code will have to be relocated to a 6031new address in RAM. 6032 6033 6034U-Boot Porting Guide: 6035---------------------- 6036 6037[Based on messages by Jerry Van Baren in the U-Boot-Users mailing 6038list, October 2002] 6039 6040 6041int main(int argc, char *argv[]) 6042{ 6043 sighandler_t no_more_time; 6044 6045 signal(SIGALRM, no_more_time); 6046 alarm(PROJECT_DEADLINE - toSec (3 * WEEK)); 6047 6048 if (available_money > available_manpower) { 6049 Pay consultant to port U-Boot; 6050 return 0; 6051 } 6052 6053 Download latest U-Boot source; 6054 6055 Subscribe to u-boot mailing list; 6056 6057 if (clueless) 6058 email("Hi, I am new to U-Boot, how do I get started?"); 6059 6060 while (learning) { 6061 Read the README file in the top level directory; 6062 Read http://www.denx.de/twiki/bin/view/DULG/Manual; 6063 Read applicable doc/*.README; 6064 Read the source, Luke; 6065 /* find . -name "*.[chS]" | xargs grep -i <keyword> */ 6066 } 6067 6068 if (available_money > toLocalCurrency ($2500)) 6069 Buy a BDI3000; 6070 else 6071 Add a lot of aggravation and time; 6072 6073 if (a similar board exists) { /* hopefully... */ 6074 cp -a board/<similar> board/<myboard> 6075 cp include/configs/<similar>.h include/configs/<myboard>.h 6076 } else { 6077 Create your own board support subdirectory; 6078 Create your own board include/configs/<myboard>.h file; 6079 } 6080 Edit new board/<myboard> files 6081 Edit new include/configs/<myboard>.h 6082 6083 while (!accepted) { 6084 while (!running) { 6085 do { 6086 Add / modify source code; 6087 } until (compiles); 6088 Debug; 6089 if (clueless) 6090 email("Hi, I am having problems..."); 6091 } 6092 Send patch file to the U-Boot email list; 6093 if (reasonable critiques) 6094 Incorporate improvements from email list code review; 6095 else 6096 Defend code as written; 6097 } 6098 6099 return 0; 6100} 6101 6102void no_more_time (int sig) 6103{ 6104 hire_a_guru(); 6105} 6106 6107 6108Coding Standards: 6109----------------- 6110 6111All contributions to U-Boot should conform to the Linux kernel 6112coding style; see the file "Documentation/CodingStyle" and the script 6113"scripts/Lindent" in your Linux kernel source directory. 6114 6115Source files originating from a different project (for example the 6116MTD subsystem) are generally exempt from these guidelines and are not 6117reformatted to ease subsequent migration to newer versions of those 6118sources. 6119 6120Please note that U-Boot is implemented in C (and to some small parts in 6121Assembler); no C++ is used, so please do not use C++ style comments (//) 6122in your code. 6123 6124Please also stick to the following formatting rules: 6125- remove any trailing white space 6126- use TAB characters for indentation and vertical alignment, not spaces 6127- make sure NOT to use DOS '\r\n' line feeds 6128- do not add more than 2 consecutive empty lines to source files 6129- do not add trailing empty lines to source files 6130 6131Submissions which do not conform to the standards may be returned 6132with a request to reformat the changes. 6133 6134 6135Submitting Patches: 6136------------------- 6137 6138Since the number of patches for U-Boot is growing, we need to 6139establish some rules. Submissions which do not conform to these rules 6140may be rejected, even when they contain important and valuable stuff. 6141 6142Please see http://www.denx.de/wiki/U-Boot/Patches for details. 6143 6144Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>; 6145see http://lists.denx.de/mailman/listinfo/u-boot 6146 6147When you send a patch, please include the following information with 6148it: 6149 6150* For bug fixes: a description of the bug and how your patch fixes 6151 this bug. Please try to include a way of demonstrating that the 6152 patch actually fixes something. 6153 6154* For new features: a description of the feature and your 6155 implementation. 6156 6157* A CHANGELOG entry as plaintext (separate from the patch) 6158 6159* For major contributions, add a MAINTAINERS file with your 6160 information and associated file and directory references. 6161 6162* When you add support for a new board, don't forget to add a 6163 maintainer e-mail address to the boards.cfg file, too. 6164 6165* If your patch adds new configuration options, don't forget to 6166 document these in the README file. 6167 6168* The patch itself. If you are using git (which is *strongly* 6169 recommended) you can easily generate the patch using the 6170 "git format-patch". If you then use "git send-email" to send it to 6171 the U-Boot mailing list, you will avoid most of the common problems 6172 with some other mail clients. 6173 6174 If you cannot use git, use "diff -purN OLD NEW". If your version of 6175 diff does not support these options, then get the latest version of 6176 GNU diff. 6177 6178 The current directory when running this command shall be the parent 6179 directory of the U-Boot source tree (i. e. please make sure that 6180 your patch includes sufficient directory information for the 6181 affected files). 6182 6183 We prefer patches as plain text. MIME attachments are discouraged, 6184 and compressed attachments must not be used. 6185 6186* If one logical set of modifications affects or creates several 6187 files, all these changes shall be submitted in a SINGLE patch file. 6188 6189* Changesets that contain different, unrelated modifications shall be 6190 submitted as SEPARATE patches, one patch per changeset. 6191 6192 6193Notes: 6194 6195* Before sending the patch, run the buildman script on your patched 6196 source tree and make sure that no errors or warnings are reported 6197 for any of the boards. 6198 6199* Keep your modifications to the necessary minimum: A patch 6200 containing several unrelated changes or arbitrary reformats will be 6201 returned with a request to re-formatting / split it. 6202 6203* If you modify existing code, make sure that your new code does not 6204 add to the memory footprint of the code ;-) Small is beautiful! 6205 When adding new features, these should compile conditionally only 6206 (using #ifdef), and the resulting code with the new feature 6207 disabled must not need more memory than the old code without your 6208 modification. 6209 6210* Remember that there is a size limit of 100 kB per message on the 6211 u-boot mailing list. Bigger patches will be moderated. If they are 6212 reasonable and not too big, they will be acknowledged. But patches 6213 bigger than the size limit should be avoided. 6214