Commit Graph

232 Commits

Author SHA1 Message Date
Artem Bityutskiy
eda95cbf75 mtd: introduce mtd_write interface
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-01-09 18:25:20 +00:00
Aaron Sierra
8e987465a1 mtd: cfi: Allow per-mapping CFI device endianness
This patch allows each CFI device map to use its own endianness. The
globally defined CFI endianness (CONFIG_MTD_CFI_NOSWAP,
CONFIG_MTD_CFI_BE_BYTE_SWAP or CONFIG_MTD_CFI_LE_BYTE_SWAP) becomes the
default value which can be overridden by a driver for a particular device.

Signed-off-by: Aaron Sierra <asierra@xes-inc.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-01-09 18:06:13 +00:00
Brian Norris
0a32a10264 mtd: cleanup style on pr_debug messages
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
2011-09-11 15:02:16 +03:00
Brian Norris
289c052221 mtd: replace DEBUG() with pr_debug()
Start moving away from the MTD_DEBUG_LEVEL messages. The dynamic
debugging feature is a generic kernel feature that provides more
flexibility.

(See Documentation/dynamic-debug-howto.txt)

Also fix some punctuation, indentation, and capitalization that went
along with the affected lines.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
2011-09-11 15:02:16 +03:00
Brian Norris
7854d3f749 mtd: spelling, capitalization, uniformity
Therefor -> Therefore
[Intern], [Internal] -> [INTERN]
[REPLACABLE] -> [REPLACEABLE]
syndrom, syndom -> syndrome
ecc -> ECC
buswith -> buswidth
endianess -> endianness
dont -> don't
occures -> occurs
independend -> independent
wihin -> within
erease -> erase
blockes -> blocks
...

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-09-11 15:02:13 +03:00
Tadashi Abe
5c8d260775 mtd: remove duplicate assignment of chip->state
This is a trivial patch which removes unnecessary assignment of chip->state
in put_chip(). It's duplicated.

Signed-off-by: Tadashi Abe <tabe@mvista.com>
Acked-by: Joakim Tjernlund <joakim.tjernlund@transmode.se>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2011-05-25 02:11:13 +01:00
Tadashi Abe
100f2341e3 mtd: fix hang-up in cfi erase and read contention
cfi erase command hangs up when erase and read contention occurs.
If read runs at the same address as erase operation, read issues
Erase-Suspend via get_chip() and the erase goes into sleep in wait queue.
But in this case, read operation exits by time-out without waking it up.

I think the other variants (0001, 0020 and lpddr) have the same problem too.
Tested and verified the patch only on CFI-0002 flash, though.

Signed-off-by: Tadashi Abe <tabe@mvista.com>
Acked-by: Joakim Tjernlund <joakim.tjernlund@transmode.se>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2011-05-25 02:11:11 +01:00
Gernot Hoyler
c9ddab25d1 mtd: cmdset_0002: add CFI 1.5 support for S29GL-S
This patch adds CFI 1.5 support for the new Spansion S29GL-S device family.
For details, see the data sheet on the Spansion web site:
http://www.spansion.com/Support/Datasheets/S29GL_128S_01GS_00_02_e.pdf

Signed-off-by: Gernot Hoyler <Gernot.Hoyler@spansion.com>
Acked-by: Guillaume LECERF <glecerf@gmail.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2011-05-25 01:51:35 +01:00
Lucas De Marchi
25985edced Fix common misspellings
Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2011-03-31 11:26:23 -03:00
Steffen Sledz
1065cda8a1 mtd: cfi: add support for AMIC flashes (e.g. A29L160AT)
Signed-off-by: Steffen Sledz <sledz@dresearch.de>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2011-03-11 14:27:01 +00:00
Anatolij Gustschin
13ce77f46c mtd: cfi: fix writebufsize initialization
When initializing mtd->writebufsize, we must take into account
possible flash chip interleaving. Wrong writebufsize initialization
caused UBIFS recovery issues resulting in unmountable UBIFS file
system on NOR flash partitions.

Signed-off-by: Anatolij Gustschin <agust@denx.de>
Acked-by: Guillaume LECERF <glecerf@gmail.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2011-03-11 14:22:46 +00:00
Joakim Tjernlund
ecf3fde07c mtd: fix race in cfi_cmdset_0001 driver
As inval_cache_and_wait_for_operation() drop and reclaim the lock
to invalidate the cache, some other thread may suspend the operation
before reaching the for(;;) loop. Therefore the loop must start with
checking the chip->state before reading status from the chip.

Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
Acked-by: Michael Cashwell <mboards@prograde.net>
Acked-by: Stefan Bigler <stefan.bigler@keymile.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Cc: stable@kernel.org
2011-03-11 12:09:07 +00:00
Antony Pavlov
ceabebb2bd mtd: jedec_probe: initialise make sector erase command variable
In the commit 08968041be
 (mtd: cfi_cmdset_0002: make sector erase command variable)
introdused a field sector_erase_cmd. In the same commit initialisation
of cfi->sector_erase_cmd made in cfi_chip_setup()
(file drivers/mtd/chips/cfi_probe.c), so the CFI chip has no problem:

...
        cfi->cfi_mode = CFI_MODE_CFI;
        cfi->sector_erase_cmd = CMD(0x30);
...

But for the JEDEC chips this initialisation is not carried out,
so the JEDEC chips have sector_erase_cmd == 0.

This patch adds the missing initialisation.

Signed-off-by: Antony Pavlov <antony@niisi.msk.ru>
Acked-by: Guillaume LECERF <glecerf@gmail.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
CC: stable@kernel.org
2011-03-11 12:05:54 +00:00
Antony Pavlov
efba2e313e mtd: jedec_probe: Change variable name from cfi_p to cfi
In the following commit, we'll need to use the CMD() macro in order to
fix the initialisation of the sector_erase_cmd field. That requires the
local variable to be called 'cfi', so change it first in a simple patch.

Signed-off-by: Antony Pavlov <antony@niisi.msk.ru>
Acked-by: Guillaume LECERF <glecerf@gmail.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
CC: stable@kernel.org
2011-03-11 12:05:24 +00:00
Anatolij Gustschin
d261c72ae0 mtd: cfi: add writebufsize initialization
Initialize mtd->writebufsize to the value obtained
by CFI query command at probe time.

Signed-off-by: Anatolij Gustschin <agust@denx.de>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2011-01-06 15:35:53 +00:00
Guillaume LECERF
e8953b7395 mtd: cfi_cmdset_0002: add support for Samsung K8D3x16UxC NOR chips
These chips report CFI v3.3 [1], so patch them on the fly to the more
correct v1.3.
Discussed and tested by the OpenWRT people [2].

[1] http://www.samsung.com/global/system/business/semiconductor/product/2007/6/11/NORFlash/32Mbit/K8D3216UBC/ds_K8D3x16UxC_rev17.pdf
[2] https://dev.openwrt.org/ticket/866

Signed-off-by: Guillaume LECERF <glecerf@gmail.com>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2011-01-06 15:28:53 +00:00
Guillaume LECERF
e637276370 mtd: cfi_cmdset_0002: add support for Samsung K8D6x16UxM NOR chips
These chips report CFI v0.0 [1], so extend cfi_fixup_major_minor()
to patch all Samsung chips from 0.0 to 1.0.
Discussed and tested by the OpenWRT people [2].

[1] http://www.samsung.com/global/system/business/semiconductor/product/2007/6/11/NORFlash/64Mbit/K8D6316UTM/ds_K8D6x16UxM_rev16.pdf
[2] https://dev.openwrt.org/ticket/7348

Signed-off-by: Guillaume LECERF <glecerf@gmail.com>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2011-01-06 15:28:51 +00:00
Guillaume LECERF
cc31822250 mtd: cfi_fixup: remove unused 'param' parameter
The 'param' parameter has never been used since its introduction, so
simply remove it.

Signed-off-by: Guillaume LECERF <glecerf@gmail.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2010-12-03 16:31:00 +00:00
David Woodhouse
67577927e8 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6.git
Conflicts:
	drivers/mtd/mtd_blkdevs.c

Merge Grant's device-tree bits so that we can apply the subsequent fixes.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2010-10-30 12:35:11 +01:00
David Woodhouse
6411bf6cdf Revert "mtd: cleanup Kconfig dependencies"
This reverts commit 432dc821c9.

The individual CFI geometry options were carefully set up to get sane
default values if the CFI_ADV_OPTIONS wasn't set, and it wasn't
appropriate to move them into an if/endif block.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2010-10-26 11:42:51 +01:00
Guillaume LECERF
08968041be mtd: cfi_cmdset_0002: make sector erase command variable
Some old SST chips use 0x50 as sector erase command, instead
of 0x30. Make this value variable to handle such chips.

Signed-off-by: Guillaume LECERF <glecerf@gmail.com>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2010-10-26 11:39:17 +01:00
Guillaume LECERF
9fc05fcada mtd: cfi_cmdset_0002: add CFI detection for SST 38VF640x chips
Add support for SST38VF640x chips in CFI mode.

Signed-off-by: Guillaume LECERF <glecerf@gmail.com>
Signed-off-by: yidong zhang <zhangyd6@gmail.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2010-10-26 11:38:48 +01:00
Guillaume LECERF
fc61015f72 mtd: cfi_util: add support for switching SST 39VF640xB chips into QRY mode
Signed-off-by: Guillaume LECERF <glecerf@gmail.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2010-10-26 11:37:26 +01:00
Guillaume LECERF
b5d194ceae mtd: cfi_cmdset_0001: use defined value of P_ID_INTEL_PERFORMANCE instead of hardcoded one
Signed-off-by: Guillaume LECERF <glecerf@gmail.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2010-10-26 11:00:18 +01:00
Wolfram Sang
d031c22643 mtd: cfi_cmdset_0002: code cleanups
- remove disabled code (hasn't been touched since the beginning of git
  and should be reimplemented if really needed)
- convert remaining c++-comments to plain c-style

Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Guillaume LECERF <glecerf@gmail.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2010-10-25 01:14:19 +01:00
H Hartley Sweeten
432dc821c9 mtd: cleanup Kconfig dependencies
Remove the MTD!=n dependency since that is handled by drivers/mtd/Kconfig.
Simplify the dependency checks for mtd/chips by using if/endif blocks. Remove
all default n since that is the Kconfig default.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2010-10-24 23:37:32 +01:00
Justin P. Mattock
631dd1a885 Update broken web addresses in the kernel.
The patch below updates broken web addresses in the kernel

Signed-off-by: Justin P. Mattock <justinmattock@gmail.com>
Cc: Maciej W. Rozycki <macro@linux-mips.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Finn Thain <fthain@telegraphics.com.au>
Cc: Randy Dunlap <rdunlap@xenotime.net>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Dimitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Mike Frysinger <vapier.adi@gmail.com>
Acked-by: Ben Pfaff <blp@cs.stanford.edu>
Acked-by: Hans J. Koch <hjk@linutronix.de>
Reviewed-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2010-10-18 11:03:14 +02:00
David Woodhouse
6ae0185fe2 mtd: Remove obsolete <mtd/compatmac.h> include
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2010-08-08 21:19:42 +01:00
Guillaume LECERF
5da195326b mtd: cfi_cmdset_0002: consider version 1.4 as a valid primary extension version
The Spansion S29WS-P device family uses CFI version 1.4 [1].
Consider it as a valid version.

[1] http://www.spansion.com/Support/Datasheets/s29ws-p_00_a12_e.pdf

Signed-off-by: Guillaume LECERF <glecerf@gmail.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2010-08-06 09:24:57 +01:00
Stefani Seibold
8ae664184c mtd: change struct flchip_shared spinlock locking into mutex
This patch prevent to schedule while atomic by changing the
flchip_shared spinlock into a mutex. This should be save since no atomic
path will use this lock.

It was suggested by Arnd Bergmann and Vasiliy Kulikov.

Signed-off-by: Stefani Seibold <stefani@seibold.net>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2010-08-06 09:22:16 +01:00
Guillaume LECERF
e17f47a14b mtd: cfi_cmdset_0002: fix the check for valid primary extension versions
Valid primary extension versions are: 1.0, 1.1, 1.2, 1.3 [1][2].
Fix the check in cfi_cmdset_0002 accordingly.

[1] http://www.amd.com/us-en/assets/content_type/DownloadableAssets/cfi_r20.pdf, page 19
[2] http://www.amd.com/us-en/assets/content_type/DownloadableAssets/cfi_100_20011201.pdf

Signed-off-by: Florian Fainelli <florian@openwrt.org>
Signed-off-by: Guillaume LECERF <glecerf@gmail.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2010-08-04 10:58:36 +01:00
Guillaume LECERF
771a115a6d mtd: cfi_probe: print manufacturer and id of probed chip
Signed-off-by: Guillaume LECERF <glecerf@gmail.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2010-08-02 09:05:20 +01:00
Richard Cochran
9938424f0c mtd: add an ioctl to query the lock status of a flash sector
This patchs adds a way for user space programs to find out whether a
flash sector is locked. An optional driver method in the mtd_info struct
provides the information.

Signed-off-by: Richard Cochran <richard.cochran@omicron.at>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2010-08-02 09:03:41 +01:00
Guillaume LECERF
8046112818 mtd: cfi_cmdset_0002: use AMD standard command-set with Winbond flash chips
Tested with W19L320SBT9C [1].

[1] http://www.datasheetarchive.com/pdf-datasheets/Datasheets-40/DSA-795343.pdf

[dwmw2: Fix MODULE_ALIAS and linkage]
Signed-off-by: Obinou <obconseil@gmail.com>
Signed-off-by: Guillaume LECERF <glecerf@gmail.com>
Acked-by: Florian Fainelli <florian@openwrt.org>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2010-05-20 16:57:00 +01:00
David Woodhouse
1e804cec7a mtd: cfi_cmdset_0002: Fix MODULE_ALIAS and linkage for new 0701 commandset ID
Signed-off-by: Guillaume LECERF <glecerf@gmail.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2010-05-20 16:56:27 +01:00
David Woodhouse
abab7ebf8c mtd: cfi_cmdset_0002: Fix argument order in bootloc warning
Doh. Pointed out by Guillaume LECERF <glecerf@gmail.com> since I managed
to miss it in my test builds. S'what I get for hacking at 2am, I suppose.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2010-05-14 09:14:27 +01:00
Wolfram Sang
087acaf1c6 mtd: chips: add SST39WF160x NOR-flashes
Due to a broken CFI, they have to be added to jedec_probe.

Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2010-05-14 02:27:46 +01:00
Artem Bityutskiy
7d84b6273c mtd: jedec_probe: remove spaces before tabs
Nothing very important, this just makes git am stop producing warnings.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2010-05-14 01:49:03 +01:00
Wolfram Sang
ae73182229 mtd: chips: use common manufacturer codes in jedec_probe()
Factor out old manufacturers and use the generic ones from cfi.h

Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2010-05-14 01:48:58 +01:00
Guillaume LECERF
087444da61 mtd: cfi_util: do not printk if no extended query table
Signed-off-by: Guillaume LECERF <glecerf@gmail.com>
Reviewed-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2010-05-14 01:39:55 +01:00
Guillaume LECERF
5a0563f0ad mtd: cfi_cmdset_0002: add CFI detection for SST 39VF{32, 64}xxB chips
This patch adds support for detecting SST 39VF32xxB and 39VF64xxB
chips in CFI mode.

Signed-off-by: Guillaume LECERF <glecerf@gmail.com>
Reviewed-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2010-05-14 01:39:43 +01:00
Guillaume LECERF
83dcd3bb11 mtd: cfi_cmdset_0002: add CFI detection for SST 39VF{16, 32}xx chips
SST 39VF{16,32}xx chips use the 0x0701 command set, fully compatible
with the AMD one. This patch adds support for detecting them in CFI
mode.

Signed-off-by: Guillaume LECERF <glecerf@gmail.com>
Reviewed-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2010-05-14 01:39:23 +01:00
David Woodhouse
412da2f6e0 mtd: cfi_cmdset_0002: Tone down warning messages about TopBottom CFI field
Accept values of 2-5 for TopBottom, where the newly-added 4 and 5 values
mean a uniform layout. It does indicate WP layout but we don't handle that.

Also don't say "broken" when swapping erase regions in a top-boot chip.
That got retrospectively documented in the spec.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2010-05-14 01:39:20 +01:00
Guillaume LECERF
564b84978d mtd: cfi_cmdset_0002: do not fail on no extended query table as they are both optional
After looking at AMD's CFI specification [1], both of the extended query
tables are optional. Thus, it looks like relying that at least one of
those tables exist is a bug in cfi_cmdset_0002.

This patch inverts the logic and checks for unlock function pointers before
exiting on error. This approach leaves place to add a call to a fixup
function to try to handle chips compatible with the early AMD specification
from 1995 [2].

[1] http://www.amd.com/us-en/assets/content_type/DownloadableAssets/cfi_r20.pdf
[2] http://noel.feld.cvut.cz/hw/amd/20158a.pdf

Signed-off-by: Guillaume LECERF <glecerf@gmail.com>
Reviewed-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2010-05-14 01:33:27 +01:00
Guillaume LECERF
5859886122 mtd: cfi_probe: use P_ID_* definitions instead of hardcoded values
Use P_ID_* definitions already in include/linux/mtd/cfi.h instead of the
hardcoded values. Make the code more readable.

Signed-off-by: Guillaume LECERF <glecerf@gmail.com>
Reviewed-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2010-05-14 01:08:19 +01:00
Guillaume LECERF
54b93a49d8 mtd: cfi_probe: add support for SST 0x0701 vendorname
SST 39VF160x and 39VF320x chips use vendorname id 0x0701 and alternative
unlock addresses. Add support for them in cfi_probe.c.

Signed-off-by: Guillaume LECERF <glecerf@gmail.com>
Reviewed-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2010-05-14 01:08:11 +01:00
Guillaume LECERF
ad7026fef6 mtd: cfi_probe: make the addresses used to enter Auto Select Mode variable
Make the addresses used to enter Auto Select Mode variable to leave place
for handling chips using non-standard addresses.

Signed-off-by: Guillaume LECERF <glecerf@gmail.com>
Reviewed-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2010-05-14 01:07:49 +01:00
Guillaume LECERF
8473044d64 mtd: cfi_probe: enter Auto Select Mode after filling cfi->cfiq members
Move the code to enter Auto Select Mode down to be able to use cfi->cfiq
members to add support for chips using alternative sequence / unlock
addresses.

Signed-off-by: Guillaume LECERF <glecerf@gmail.com>
Reviewed-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2010-05-14 01:07:42 +01:00
Kevin Cernekee
eafe1311aa mtd: cfi_cmdset_0002: Add reboot notifier for AMD flashes
Ensure that the flash device is in a quiescent state before rebooting.
The implementation is closely modeled after the cfi_cmdset_0001 reboot
notifier, commit 963a6fb0a0 .

Signed-off-by: Kevin Cernekee <cernekee@gmail.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2010-05-10 14:25:12 +01:00
Stefani Seibold
c4e773764c mtd: fix a huge latency problem in the MTD CFI and LPDDR flash drivers.
The use of a memcpy() during a spinlock operation will cause very long
thread context switch delays if the flash chip bandwidth is low and the
data to be copied large, because a spinlock will disable preemption.

For example: A flash with 6,5 MB/s bandwidth will cause under ubifs,
which request sometimes 128 KiB (the flash erase size), a preemption delay of
20 milliseconds. High priority threads will not be served during this
time, regardless whether this threads access the flash or not. This behavior
breaks real time.

The patch changes all the use of spin_lock operations for xxxx->mutex
into mutex operations, which is exact what the name says and means.

I have checked the code of the drivers and there is no use of atomic
pathes like interrupt or timers. The mtdoops facility will also not be used
by this drivers. So it is dave to replace the spin_lock against mutex.

There is no performance regression since the mutex is normally not
acquired.

Changelog:
 06.03.2010 First release
 26.03.2010 Fix mutex[1] issue and tested it for compile failure

Signed-off-by: Stefani Seibold <stefani@seibold.net>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2010-05-10 14:22:30 +01:00