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authorGrant Likely <grant.likely@linaro.org>2011-03-28 09:58:43 +0000
committerGerald Van Baren <gvb@unssw.com>2011-04-25 21:11:20 -0400
commitc3624e6ed0a36f54aa0b3e7f32d30a6fde434f51 (patch)
tree9a9de9718b28b0a526708466f5eb12782352607d /README
parent590d3cacb98cb377b127869b58507d2afe9c904a (diff)
downloadu-boot-linaro-stable-c3624e6ed0a36f54aa0b3e7f32d30a6fde434f51.tar.gz
Default to bootm_size() when CONFIG_SYS_BOOTMAPSZ is not defined
This patch adds a function getenv_bootm_mapsize() for obtaining the size of the early mapped region accessible by the kernel during early boot. It defaults to CONFIG_SYS_BOOTMAPSZ, or if not defined, defaults to getenv_bootm_size(), which in turn defaults to the size of RAM. getenv_bootm_mapsize() can also be overridden with a "bootm_mapsize" environmental variable. Signed-off-by: Grant Likely <grant.likely@linaro.org>
Diffstat (limited to 'README')
-rw-r--r--README16
1 files changed, 14 insertions, 2 deletions
diff --git a/README b/README
index cdbb9de02..b647ecac3 100644
--- a/README
+++ b/README
@@ -2348,7 +2348,10 @@ Configuration Settings:
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" + CONFIG_SYS_BOOTMAPSZ.
+ and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment
+ variable "bootm_mapsize" will override the value of
+ CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined,
+ then the value in "bootm_size" will be used instead.
- CONFIG_SYS_BOOT_RAMDISK_HIGH:
Enable initrd_high functionality. If defined then the
@@ -3184,7 +3187,16 @@ List of environment variables (most likely not complete):
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 description of CONFIG_SYS_BOOTMAPSZ.
+ kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and
+ bootm_mapsize.
+
+ bootm_mapsize - Size of the initial memory mapping for the Linux kernel.
+ This variable is given as a hexadecimal number and it
+ defines the size of the memory region starting at base
+ address bootm_low that is accessible by the Linux kernel
+ during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used
+ as the default value if it is defined, and bootm_size is
+ used otherwise.
bootm_size - Memory range available for image processing in the bootm
command can be restricted. This variable is given as