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path: root/drivers/mtd/lpddr
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2010-05-13drivers/mtd: Use kzallocJulia Lawall
Use kzalloc rather than the combination of kmalloc and memset. The semantic patch that makes this change is as follows: (http://coccinelle.lip6.fr/) // <smpl> @@ expression x,size,flags; statement S; @@ -x = kmalloc(size,flags); +x = kzalloc(size,flags); if (x == NULL) S -memset(x, 0, size); // </smpl> Signed-off-by: Julia Lawall <julia@diku.dk> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2010-05-10Merge branch 'master' of ↵David Woodhouse
git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6 Conflicts: drivers/mtd/mtdcore.c Pull in the bdi fixes and ARM platform changes that other outstanding patches depend on.
2010-05-10mtd: fix a huge latency problem in the MTD CFI and LPDDR flash drivers.Stefani Seibold
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>
2010-03-30include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo
implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2009-11-09Kconfig: Remove useless and sometimes wrong commentsMichael Roth
Additionally, some excessive newlines removed. Signed-off-by: Michael Roth <mroth@nessie.de> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2009-01-11[MTD] [LPDDR] qinfo_probe depends on lpddrAlexey Korolev
Signed-off-by: Alexey Korolev <akorolev@infradead.org> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2009-01-05[MTD] LPDDR Makefile and KConfigAlexey Korolev
We have two components to manage LPDDR flash memories in Linux. 1. It is a driver for chip probing and reading its capabilities 2. It is a device operations driver. Signed-off-by: Alexey Korolev <akorolev@infradead.org> Acked-by: Jared Hulbert <jaredeh@gmail.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2009-01-05[MTD] LPDDR Command set driverAlexey Korolev
Driver which handles device command operation. Details on device operations are available here: http://www.numonyx.com/Documents/Datasheets/DS-315768_Velocity-Discrete.pdf Signed-off-by: Alexey Korolev <akorolev@infradead.org> Acked-by: Jared Hulbert <jaredeh@gmail.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2009-01-05[MTD] LPDDR qinfo probing.Alexey Korolev
LPDDR flash chips are based on completely new kind of chips probing. Device capabilities are available via special request. We sent field request command which contains Major and Minor numbers - and recieve corresponend value. All requests are performed within PFOW window. Detailed information about qinfo records can be found here: http://www.numonyx.com/Documents/Datasheets/DS-315768_Velocity-Discrete.pdf Signed-off-by: Alexey Korolev <akorolev@infradead.org> Acked-by: Jared Hulbert <jaredeh@gmail.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>