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authorScott Wood <scottwood@freescale.com>2010-09-17 14:38:37 -0500
committerScott Wood <scottwood@freescale.com>2010-10-11 15:11:33 -0500
commitfdd813def82c3405cb999c05154212bacd7b6126 (patch)
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parent36650ca9f16ac507bb0926d3a3ec5340986fcce0 (diff)
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README: Add new NAND env features
CONFIG_ENV_SIZE does not need block alignment. Document CONFIG_ENV_RANGE and CONFIG_ENV_OFFSET_OOB. Signed-off-by: Scott Wood <scottwood@freescale.com>
Diffstat (limited to 'README')
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1 files changed, 23 insertions, 9 deletions
diff --git a/README b/README
index f997a5d..197804e 100644
--- a/README
+++ b/README
@@ -2534,18 +2534,32 @@ to save the current settings.
- CONFIG_ENV_SIZE:
These two #defines specify the offset and size of the environment
- area within the first NAND device.
+ area within the first NAND device. CONFIG_ENV_OFFSET must be
+ aligned to an erase block boundary.
- - CONFIG_ENV_OFFSET_REDUND
+ - CONFIG_ENV_OFFSET_REDUND (optional):
This setting describes a second storage area of CONFIG_ENV_SIZE
- size used to hold a redundant copy of the environment data,
- so that there is a valid backup copy in case there is a
- power failure during a "saveenv" operation.
-
- Note: CONFIG_ENV_OFFSET and CONFIG_ENV_OFFSET_REDUND must be aligned
- to a block boundary, and CONFIG_ENV_SIZE must be a multiple of
- the NAND devices block size.
+ size used to hold a redundant copy of the environment data, so
+ that there is a valid backup copy in case there is a power failure
+ during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be
+ aligned to an erase block boundary.
+
+ - CONFIG_ENV_RANGE (optional):
+
+ Specifies the length of the region in which the environment
+ can be written. This should be a multiple of the NAND device's
+ block size. Specifying a range with more erase blocks than
+ are needed to hold CONFIG_ENV_SIZE allows bad blocks within
+ the range to be avoided.
+
+ - CONFIG_ENV_OFFSET_OOB (optional):
+
+ Enables support for dynamically retrieving the offset of the
+ environment from block zero's out-of-band data. The
+ "nand env.oob" command can be used to record this offset.
+ Currently, CONFIG_ENV_OFFSET_REDUND is not supported when
+ using CONFIG_ENV_OFFSET_OOB.
- CONFIG_NAND_ENV_DST