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| author | Joakim Tjernlund <joakim.tjernlund@transmode.se> | 2009-11-19 12:01:58 +0100 |
|---|---|---|
| committer | David Woodhouse <David.Woodhouse@intel.com> | 2009-11-30 09:58:53 +0000 |
| commit | 2695eab964efaa382168e0351705967bd9deb7ea (patch) | |
| tree | 41c2711f7849f6a0be9ce388fad33fb4ddb62ffa | |
| parent | c1317f7163d287805b8e12af12d04a2a6ead865c (diff) | |
| download | op-kernel-dev-2695eab964efaa382168e0351705967bd9deb7ea.zip op-kernel-dev-2695eab964efaa382168e0351705967bd9deb7ea.tar.gz | |
mtd: CFI cmdset_0002: enable erase-suspend-program
Erase-suspend for writing is required to avoid blocking applications
that wish to write some data (to a NOR block other than the one being
erased). Particularly, it solves some huge delays that an application
(which writes to a UBIFS) will experience if UBI attaches to empty NOR
flash. In this case the UBI background thread will erase a lot of blocks
and the application can be blocked for minutes because of the "MTD/CFI
chip lock".
This feature has been disabled for years. Maybe this was because the old
code turned it on for erase-suspend read-only chips also
(cfip->EraseSuspend & 0x1). This is wrong and corrected now.
This patch was tweaked by Norbert van Bolhuis.
Signed-off-by: Norbert van Bolhuis <nvbolhuis@aimvalley.nl>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
| -rw-r--r-- | drivers/mtd/chips/cfi_cmdset_0002.c | 16 |
1 files changed, 3 insertions, 13 deletions
diff --git a/drivers/mtd/chips/cfi_cmdset_0002.c b/drivers/mtd/chips/cfi_cmdset_0002.c index 94bb61e..1d49e18 100644 --- a/drivers/mtd/chips/cfi_cmdset_0002.c +++ b/drivers/mtd/chips/cfi_cmdset_0002.c @@ -490,10 +490,6 @@ static struct mtd_info *cfi_amdstd_setup(struct mtd_info *mtd) } #endif - /* FIXME: erase-suspend-program is broken. See - http://lists.infradead.org/pipermail/linux-mtd/2003-December/009001.html */ - printk(KERN_NOTICE "cfi_cmdset_0002: Disabling erase-suspend-program due to code brokenness.\n"); - __module_get(THIS_MODULE); return mtd; @@ -589,15 +585,9 @@ static int get_chip(struct map_info *map, struct flchip *chip, unsigned long adr return 0; case FL_ERASING: - if (mode == FL_WRITING) /* FIXME: Erase-suspend-program appears broken. */ - goto sleep; - - if (!( mode == FL_READY - || mode == FL_POINT - || !cfip - || (mode == FL_WRITING && (cfip->EraseSuspend & 0x2)) - || (mode == FL_WRITING && (cfip->EraseSuspend & 0x1) - ))) + if (!cfip || !(cfip->EraseSuspend & (0x1|0x2)) || + !(mode == FL_READY || mode == FL_POINT || + (mode == FL_WRITING && (cfip->EraseSuspend & 0x2)))) goto sleep; /* We could check to see if we're trying to access the sector |
