diff --git a/README b/README index 664d88a5505..e10a4bc472a 100644 --- a/README +++ b/README @@ -1033,130 +1033,6 @@ typically in board_init_f() and board_init_r(). - CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r() - CONFIG_BOARD_LATE_INIT: Call board_late_init() -Configuration Settings: ------------------------ - -- CONFIG_SYS_LONGHELP: Defined when you want long help messages included; - undefine this when you're short of memory. - -- CFG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default - width of the commands listed in the 'help' command output. - -- CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to - prompt for user input. - -- CFG_SYS_BAUDRATE_TABLE: - List of legal baudrate settings for this board. - -- CFG_SYS_MEM_RESERVE_SECURE - Only implemented for ARMv8 for now. - If defined, the size of CFG_SYS_MEM_RESERVE_SECURE memory - is substracted from total RAM and won't be reported to OS. - This memory can be used as secure memory. A variable - gd->arch.secure_ram is used to track the location. In systems - the RAM base is not zero, or RAM is divided into banks, - this variable needs to be recalcuated to get the address. - -- CFG_SYS_SDRAM_BASE: - Physical start address of SDRAM. _Must_ be 0 here. - -- CFG_SYS_FLASH_BASE: - Physical start address of Flash memory. - -- CONFIG_SYS_MALLOC_LEN: - Size of DRAM reserved for malloc() use. - -- CFG_SYS_BOOTMAPSZ: - Maximum size of memory mapped by the startup code of - the Linux kernel; all data that must be processed by - the Linux kernel (bd_info, boot arguments, FDT blob if - used) must be put below this limit, unless "bootm_low" - environment variable is defined and non-zero. In such case - all data for the Linux kernel must be between "bootm_low" - and "bootm_low" + CFG_SYS_BOOTMAPSZ. The environment - variable "bootm_mapsize" will override the value of - CFG_SYS_BOOTMAPSZ. If CFG_SYS_BOOTMAPSZ is undefined, - then the value in "bootm_size" will be used instead. - -- CONFIG_SYS_BOOT_GET_CMDLINE: - Enables allocating and saving kernel cmdline in space between - "bootm_low" and "bootm_low" + BOOTMAPSZ. - -- CONFIG_SYS_BOOT_GET_KBD: - Enables allocating and saving a kernel copy of the bd_info in - space between "bootm_low" and "bootm_low" + BOOTMAPSZ. - -- CONFIG_SYS_FLASH_PROTECTION - If defined, hardware flash sectors protection is used - instead of U-Boot software protection. - -- CONFIG_SYS_FLASH_CFI: - Define if the flash driver uses extra elements in the - common flash structure for storing flash geometry. - -- CONFIG_FLASH_CFI_DRIVER - This option also enables the building of the cfi_flash driver - in the drivers directory - -- CONFIG_FLASH_CFI_MTD - This option enables the building of the cfi_mtd driver - in the drivers directory. The driver exports CFI flash - to the MTD layer. - -- CONFIG_SYS_FLASH_USE_BUFFER_WRITE - Use buffered writes to flash. - -The following definitions that deal with the placement and management -of environment data (variable area); in general, we support the -following configurations: - -BE CAREFUL! The first access to the environment happens quite early -in U-Boot initialization (when we try to get the setting of for the -console baudrate). You *MUST* have mapped your NVRAM area then, or -U-Boot will hang. - -Please note that even with NVRAM we still use a copy of the -environment in RAM: we could work on NVRAM directly, but we want to -keep settings there always unmodified except somebody uses "saveenv" -to save the current settings. - -BE CAREFUL! For some special cases, the local device can not use -"saveenv" command. For example, the local device will get the -environment stored in a remote NOR flash by SRIO or PCIE link, -but it can not erase, write this NOR flash by SRIO or PCIE interface. - -- CONFIG_NAND_ENV_DST - - Defines address in RAM to which the nand_spl code should copy the - environment. If redundant environment is used, it will be copied to - CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE. - -Please note that the environment is read-only until the monitor -has been relocated to RAM and a RAM copy of the environment has been -created; also, when using EEPROM you will have to use env_get_f() -until then to read environment variables. - -The environment is protected by a CRC32 checksum. Before the monitor -is relocated into RAM, as a result of a bad CRC you will be working -with the compiled-in default environment - *silently*!!! [This is -necessary, because the first environment variable we need is the -"baudrate" setting for the console - if we have a bad CRC, we don't -have any device yet where we could complain.] - -Note: once the monitor has been relocated, then it will complain if -the default environment is used; a new CRC is computed as soon as you -use the "saveenv" command to store a valid environment. - -- CONFIG_DISPLAY_BOARDINFO - Display information about the board that U-Boot is running on - when U-Boot starts up. The board function checkboard() is called - to do this. - -- CONFIG_DISPLAY_BOARDINFO_LATE - Similar to the previous option, but display this information - later, once stdio is running and output goes to the LCD, if - present. - Low Level (hardware related) configuration options: ---------------------------------------------------