From fdd813def82c3405cb999c05154212bacd7b6126 Mon Sep 17 00:00:00 2001 From: Scott Wood Date: Fri, 17 Sep 2010 14:38:37 -0500 Subject: 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 --- README | 32 +++++++++++++++++++++++--------- 1 file changed, 23 insertions(+), 9 deletions(-) (limited to 'README') diff --git a/README b/README index f997a5d86..197804e35 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 -- cgit v1.2.3