Boot-related documentation update

[karo-tx-uboot.git] / README

diff --git a/README b/README
index 20751191bd8253478a8040343688615449d8afc8..3a10bd762b5d6af892eecec09eae2276aabae97c 100644 (file)
--- a/README
+++ b/README
@@ -1997,8 +1997,11 @@ Configuration Settings:
 - CFG_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, eventually
-               initrd image) must be put below this limit.
+               the Linux kernel (bd_info, boot arguments, FDT blob if
+               used) must be put below this limit, unless "bootm_low"
+               enviroment variable is defined and non-zero. In such case
+               all data for the Linux kernel must be between "bootm_low"
+               and "bootm_low" + CFG_BOOTMAPSZ.
 
 - CFG_MAX_FLASH_BANKS:
                Max number of Flash memory banks
@@ -2043,6 +2046,13 @@ Configuration Settings:
                This option also enables the building of the cfi_flash driver
                in the drivers directory
 
+- CFG_FLASH_USE_BUFFER_WRITE
+               Use buffered writes to flash.
+
+- CONFIG_FLASH_SPANSION_S29WS_N
+               s29ws-n MirrorBit flash has non-standard addresses for buffered
+               write commands.
+
 - CFG_FLASH_QUIET_TEST
                If this option is defined, the common CFI flash doesn't
                print it's warning upon not recognized FLASH banks. This
@@ -2736,6 +2746,20 @@ Some configuration options can be set using Environment Variables:
 
   bootfile     - Name of the image to load with TFTP
 
+  bootm_low    - Memory range available for image processing in the bootm
+                 command can be restricted. This variable is given as
+                 a hexadecimal number and defines lowest address allowed
+                 for use by the bootm command. See also "bootm_size"
+                 environment variable. Address defined by "bootm_low" is
+                 also the base of the initial memory mapping for the Linux
+                 kernel -- see the descripton of CFG_BOOTMAPSZ.
+
+  bootm_size   - Memory range available for image processing in the bootm
+                 command can be restricted. This variable is given as
+                 a hexadecimal number and defines the size of the region
+                 allowed for use by the bootm command. See also "bootm_low"
+                 environment variable.
+
   autoload     - if set to "no" (any string beginning with 'n'),
                  "bootp" will just load perform a lookup of the
                  configuration from the BOOTP server, but not try to