linux/drivers/mtd
Anton Vorontsov 452db27243 [MTD] [NAND] fsl_elbc_nand: fix OOB workability for large page NAND chips
For large page chips, nand_bbt is looking into OOB area, and checking
for "0xff 0xff" pattern at OOB offset 0. That is, two bytes should be
reserved for bbt means.

But ELBC driver is specifying ecclayout so that oobfree area starts at
offset 1, so only one byte left for the bbt purposes.

This causes problems with any OOB users, namely JFFS2: after first mount
JFFS2 will fill all OOBs with "erased marker", so OOBs will contain:

  OOB Data: ff 19 85 20 03 00 ff ff ff 00 00 08 ff ff ff ff
  OOB Data: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
  OOB Data: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
  OOB Data: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff

And on the next boot, NAND core will rescan for bad blocks, then will
see "0xff 0x19" pattern, and will mark all blocks as bad ones.

To fix the issue we should implement our own bad block pattern: just one
byte at OOB start. Though, this will work only for x8 chips. For x16
chips two bytes must be checked. Since ELBC driver does not support x16
NANDs (yet), we're safe for now.

Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Acked-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2008-07-11 18:12:01 +01:00
..
chips MTD/JFFS2: remove CVS keywords 2008-06-04 17:50:17 +01:00
devices [MTD] m25p80: fix bug - ATmel spi flash fails to be copied to 2008-07-11 14:44:32 +01:00
maps Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6 2008-07-11 14:36:25 +01:00
nand [MTD] [NAND] fsl_elbc_nand: fix OOB workability for large page NAND chips 2008-07-11 18:12:01 +01:00
onenand Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6 2008-07-11 14:36:25 +01:00
ubi UBI: add a message 2008-04-23 11:32:10 +01:00
afs.c MTD/JFFS2: remove CVS keywords 2008-06-04 17:50:17 +01:00
ar7part.c [MTD] Clean up AR7 partition map support 2008-04-23 09:39:49 +01:00
cmdlinepart.c MTD/JFFS2: remove CVS keywords 2008-06-04 17:50:17 +01:00
ftl.c MTD/JFFS2: remove CVS keywords 2008-06-04 17:50:17 +01:00
inftlcore.c MTD/JFFS2: remove CVS keywords 2008-06-04 17:50:17 +01:00
inftlmount.c MTD/JFFS2: remove CVS keywords 2008-06-04 17:50:17 +01:00
Kconfig MTD/JFFS2: remove CVS keywords 2008-06-04 17:50:17 +01:00
Makefile [MTD] AR7 mtd partition map 2008-04-22 20:48:12 +01:00
mtd_blkdevs.c [MTD] Use list_for_each_entry[_safe] where appropriate. 2008-06-04 17:53:31 +01:00
mtdblock_ro.c MTD/JFFS2: remove CVS keywords 2008-06-04 17:50:17 +01:00
mtdblock.c MTD/JFFS2: remove CVS keywords 2008-06-04 17:50:17 +01:00
mtdchar.c [MTD] mtdchar.c remove shadowed variable warnings 2008-07-11 14:47:25 +01:00
mtdconcat.c MTD/JFFS2: remove CVS keywords 2008-06-04 17:50:17 +01:00
mtdcore.c [MTD] Use list_for_each_entry[_safe] where appropriate. 2008-06-04 17:53:31 +01:00
mtdcore.h [MTD] mtdcore.c: share syms with mtd_blkdev.c 2007-06-28 20:24:50 +01:00
mtdoops.c [MTD] mtdoops.c: make struct oops_cxt static again 2008-04-22 12:35:34 +01:00
mtdpart.c [MTD] Use list_for_each_entry[_safe] where appropriate. 2008-06-04 17:53:31 +01:00
mtdsuper.c Introduce path_put() 2008-02-14 21:13:33 -08:00
nftlcore.c MTD/JFFS2: remove CVS keywords 2008-06-04 17:50:17 +01:00
nftlmount.c MTD/JFFS2: remove CVS keywords 2008-06-04 17:50:17 +01:00
ofpart.c [MTD] mtd/ofpart.c: add MODULE_LICENSE 2008-04-22 15:53:52 +01:00
redboot.c Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6 2008-07-11 14:36:25 +01:00
rfd_ftl.c MTD/JFFS2: remove CVS keywords 2008-06-04 17:50:17 +01:00
ssfdc.c [MTD] Fix ssfdc blksize typo 2006-12-11 09:43:38 +00:00