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authorBen Gardiner <bengardiner@nanometrics.ca>2011-06-14 16:35:07 -0400
committerScott Wood <scottwood@freescale.com>2011-07-01 15:56:51 -0500
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cmd_nand: add nand write.trimffs command
Add another nand write. variant, trimffs. This command will request of nand_write_skip_bad() that all trailing all-0xff pages will be dropped from eraseblocks when they are written to flash as-per the reccommended behaviour of the UBI FAQ [1]. The function that implements this timming is the drop_ffs() function by Artem Bityutskiy, ported from the mtd-utils tree. [1] http://www.linux-mtd.infradead.org/doc/ubi.html#L_flasher_algo Signed-off-by: Ben Gardiner <bengardiner@nanometrics.ca> CC: Artem Bityutskiy <dedekind1@gmail.com> CC: Detlev Zundel <dzu@denx.de> Acked-by: Scott Wood <scottwood@freescale.com> Signed-off-by: Scott Wood <scottwood@freescale.com>
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diff --git a/doc/README.nand b/doc/README.nand
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--- a/doc/README.nand
+++ b/doc/README.nand
@@ -78,6 +78,16 @@ Commands:
should work well, but loading an image copied from another flash is
going to be trouble if there are any bad blocks.
+ nand write.trimffs addr ofs|partition size
+ Enabled by the CONFIG_CMD_NAND_TRIMFFS macro. This command will write to
+ the NAND flash in a manner identical to the 'nand write' command
+ described above -- with the additional check that all pages at the end
+ of eraseblocks which contain only 0xff data will not be written to the
+ NAND flash. This behaviour is required when flashing UBI images
+ containing UBIFS volumes as per the UBI FAQ[1].
+
+ [1] http://www.linux-mtd.infradead.org/doc/ubi.html#L_flasher_algo
+
nand write.oob addr ofs|partition size
Write `size' bytes from `addr' to the out-of-band data area
corresponding to `ofs' in NAND flash. This is limited to the 16 bytes