Commit Graph

189 Commits

Author SHA1 Message Date
Nicolas Pitre 365ec7b173 ARM: add IPI tracepoints
The strings used to list IPIs in /proc/interrupts are reused for tracing
purposes.

While at it, prevent a negative ipinr from escaping the range check
in handle_IPI().

Link: http://lkml.kernel.org/p/1406318733-26754-4-git-send-email-nicolas.pitre@linaro.org

Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-08-07 20:40:41 -04:00
Viresh Kumar 0b443ead71 cpufreq: remove unused notifier: CPUFREQ_{SUSPENDCHANGE|RESUMECHANGE}
Two cpufreq notifiers CPUFREQ_RESUMECHANGE and CPUFREQ_SUSPENDCHANGE have
not been used for some time, so remove them to clean up code a bit.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
[rjw: Changelog]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-03-19 14:10:24 +01:00
Russell King 668bc38669 ARM: SMP implementations are not supposed to return from smp_ops.cpu_die()
Although we allow recovery in this case, this is not supposed to be
the normal path for hotplugging a CPU back in.  This path only exists
to serve those rare platforms where it's not possible to power down
the CPU or reset the CPU.  This patch causes the kernel to print a
message when a platform uses this path.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-01-21 16:42:14 +00:00
Nicolas Pitre efcfc46e8a ARM: 7918/1: clean up cache handling in core code
We have a handy macro to replace open coded __cpuc_flush_dcache_area(()
and outer_clean_range() sequences. Let's use it. No functional change.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-12-29 12:32:38 +00:00
Russell King df762eccba Merge branch 'devel-stable' into for-next
Conflicts:
	arch/arm/include/asm/atomic.h
	arch/arm/include/asm/hardirq.h
	arch/arm/kernel/smp.c
2013-11-12 10:58:59 +00:00
Stephen Boyd c682e51dbc ARM: 7887/1: Don't smp_cross_call() on UP devices in arch_irq_work_raise()
If we're running a kernel compiled with SMP_ON_UP=y and the
hardware only supports UP operation there isn't any
smp_cross_call function assigned. Unfortunately, we call
smp_cross_call() unconditionally in arch_irq_work_raise() and
crash the kernel on UP devices. Check to make sure we're running
on an SMP device before calling smp_cross_call() here.

Unable to handle kernel NULL pointer dereference at virtual address 00000000
pgd = c0004000
[00000000] *pgd=00000000
Internal error: Oops: 80000005 [#1] SMP ARM
Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.12.0-rc6-00018-g8d45144-dirty #16
task: de05b440 ti: de05c000 task.ti: de05c000
PC is at 0x0
LR is at arch_irq_work_raise+0x3c/0x48
pc : [<00000000>]    lr : [<c0019590>]    psr: 60000193
sp : de05dd60  ip : 00000001  fp : 00000000
r10: c085e2f0  r9 : de05c000  r8 : c07be0a4
r7 : de05c000  r6 : de05c000  r5 : c07c5778  r4 : c0824554
r3 : 00000000  r2 : 00000000  r1 : 00000006  r0 : c0529a58
Flags: nZCv  IRQs off  FIQs on  Mode SVC_32  ISA ARM Segment kernel
Control: 10c5387d  Table: 80004019  DAC: 00000017
Process swapper/0 (pid: 1, stack limit = 0xde05c248)
Stack: (0xde05dd60 to 0xde05e000)
dd60: c07b9dbc c00cb2dc 00000001 c08242c0 c08242c0 60000113 c07be0a8 c00b0590
dd80: de05c000 c085e2f0 c08242c0 c08242c0 c1414c28 c00b07cc de05b440 c1414c28
dda0: c08242c0 c00b0af8 c0862bb0 c0862db0 c1414cd8 de05c028 c0824840 de05ddb8
ddc0: 00000000 00000009 00000001 00000024 c07be0a8 c07be0a4 de05c000 c085e2f0
dde0: 00000000 c004a4b0 00000010 de00d2dc 00000054 00000100 00000024 00000000
de00: de05c028 0000000a ffff8ae7 00200040 00000016 de05c000 60000193 de05c000
de20: 00000054 00000000 00000000 00000000 00000000 c004a704 00000000 de05c008
de40: c07ba254 c004aa1c c07c5778 c0014b70 fa200000 00000054 de05de80 c0861244
de60: 00000000 c0008634 de05b440 c051c778 20000113 ffffffff de05deb4 c051d0a4
de80: 00000001 00000001 00000000 de05b440 c082afac de057ac0 de057ac0 de0443c0
dea0: 00000000 00000000 00000000 00000000 c082afbc de05dec8 c009f2a0 c051c778
dec0: 20000113 ffffffff 00000000 c016edb0 00000000 000002b0 de057ac0 de057ac0
dee0: 00000000 c016ee40 c0875e50 de05df2e de057ac0 00000000 00000013 00000000
df00: 00000000 c016f054 de043600 de0443c0 c008eb38 de004ec0 c0875e50 c008eb44
df20: 00000012 00000000 00000000 3931f0f8 00000000 00000000 00000014 c0822e84
df40: 00000000 c008ed2c 00000000 00000000 00000000 c07b7490 c07b7490 c075ab3c
df60: 00000000 c00701ac 00000002 00000000 c0070160 dffadb73 7bf8edb4 00000000
df80: c051092c 00000000 00000000 00000000 00000000 00000000 00000000 c0510934
dfa0: de05aa40 00000000 c051092c c0013ce8 00000000 00000000 00000000 00000000
dfc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
dfe0: 00000000 00000000 00000000 00000000 00000013 00000000 07efffe5 4dfac6f5
[<c0019590>] (arch_irq_work_raise+0x3c/0x48) from [<c00cb2dc>] (irq_work_queue+0xe4/0xf8)
[<c00cb2dc>] (irq_work_queue+0xe4/0xf8) from [<c00b0590>] (rcu_accelerate_cbs+0x1d4/0x1d8)
[<c00b0590>] (rcu_accelerate_cbs+0x1d4/0x1d8) from [<c00b07cc>] (rcu_start_gp+0x34/0x48)
[<c00b07cc>] (rcu_start_gp+0x34/0x48) from [<c00b0af8>] (rcu_process_callbacks+0x318/0x608)
[<c00b0af8>] (rcu_process_callbacks+0x318/0x608) from [<c004a4b0>] (__do_softirq+0x114/0x2a0)
[<c004a4b0>] (__do_softirq+0x114/0x2a0) from [<c004a704>] (do_softirq+0x6c/0x74)
[<c004a704>] (do_softirq+0x6c/0x74) from [<c004aa1c>] (irq_exit+0xac/0x100)
[<c004aa1c>] (irq_exit+0xac/0x100) from [<c0014b70>] (handle_IRQ+0x54/0xb4)
[<c0014b70>] (handle_IRQ+0x54/0xb4) from [<c0008634>] (omap3_intc_handle_irq+0x60/0x74)
[<c0008634>] (omap3_intc_handle_irq+0x60/0x74) from [<c051d0a4>] (__irq_svc+0x44/0x5c)
Exception stack(0xde05de80 to 0xde05dec8)
de80: 00000001 00000001 00000000 de05b440 c082afac de057ac0 de057ac0 de0443c0
dea0: 00000000 00000000 00000000 00000000 c082afbc de05dec8 c009f2a0 c051c778
dec0: 20000113 ffffffff
[<c051d0a4>] (__irq_svc+0x44/0x5c) from [<c051c778>] (_raw_spin_unlock_irq+0x28/0x2c)
[<c051c778>] (_raw_spin_unlock_irq+0x28/0x2c) from [<c016edb0>] (proc_alloc_inum+0x30/0xa8)
[<c016edb0>] (proc_alloc_inum+0x30/0xa8) from [<c016ee40>] (proc_register+0x18/0x130)
[<c016ee40>] (proc_register+0x18/0x130) from [<c016f054>] (proc_mkdir_data+0x44/0x6c)
[<c016f054>] (proc_mkdir_data+0x44/0x6c) from [<c008eb44>] (register_irq_proc+0x6c/0x128)
[<c008eb44>] (register_irq_proc+0x6c/0x128) from [<c008ed2c>] (init_irq_proc+0x74/0xb0)
[<c008ed2c>] (init_irq_proc+0x74/0xb0) from [<c075ab3c>] (kernel_init_freeable+0x84/0x1c8)
[<c075ab3c>] (kernel_init_freeable+0x84/0x1c8) from [<c0510934>] (kernel_init+0x8/0x150)
[<c0510934>] (kernel_init+0x8/0x150) from [<c0013ce8>] (ret_from_fork+0x14/0x2c)
Code: bad PC value

Fixes: bf18525fd7 "ARM: 7872/1: Support arch_irq_work_raise() via self IPIs"

Reported-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Tested-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-11-09 00:00:07 +00:00
Stephen Boyd bf18525fd7 ARM: 7872/1: Support arch_irq_work_raise() via self IPIs
By default, IRQ work is run from the tick interrupt (see
irq_work_run() in update_process_times()). When we're in full
NOHZ mode, restarting the tick requires the use of IRQ work and
if the only place we run IRQ work is in the tick interrupt we
have an unbreakable cycle. Implement arch_irq_work_raise() via
self IPIs to break this cycle and get the tick started again.
Note that we implement this via IPIs which are only available on
SMP builds. This shouldn't be a problem because full NOHZ is only
supported on SMP builds anyway.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Reviewed-by: Kevin Hilman <khilman@linaro.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-11-07 00:21:26 +00:00
Russell King 8754c4bf2a Merge branch 'for-rmk/arm-mm-lpae' of git://git.kernel.org/pub/scm/linux/kernel/git/ssantosh/linux-keystone into devel-stable
This series extends the existing ARM v2p runtime patching for 64 bit.
Needed for LPAE machines which have physical memory beyond 4GB.
2013-10-18 19:16:01 +01:00
Santosh Shilimkar 4dc9a81715 ARM: mm: Introduce virt_to_idmap() with an arch hook
On some PAE systems (e.g. TI Keystone), memory is above the
32-bit addressable limit, and the interconnect provides an
aliased view of parts of physical memory in the 32-bit addressable
space.  This alias is strictly for boot time usage, and is not
otherwise usable because of coherency limitations. On such systems,
the idmap mechanism needs to take this aliased mapping into account.

This patch introduces virt_to_idmap() and a arch function pointer which
can be populated by platform which needs it. Also populate necessary
idmap spots with now available virt_to_idmap(). Avoided #ifdef approach
to be compatible with multi-platform builds.

Most architecture won't touch it and in that case virt_to_idmap()
fall-back to existing virt_to_phys() macro.

Cc: Russell King <linux@arm.linux.org.uk>

Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
2013-10-10 20:25:06 -04:00
Nicolas Pitre 5135d875e1 ARM: SMP: basic IPI triggered completion support
We need a mechanism to let an inbound CPU signal that it is alive before
even getting into the kernel environment i.e. from early assembly code.
Using an IPI is the simplest way to achieve that.

This adds some basic infrastructure to register a struct completion
pointer to be "completed" when the dedicated IPI for this task is
received.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
2013-09-23 18:47:26 -04:00
Linus Torvalds 8e73e367f7 ARM: SoC cleanups for 3.12
This branch contains code cleanups, moves and removals for 3.12.
 
 There's a large number of various cleanups, and a nice net removal of
 13500 lines of code.
 
 Highlights worth mentioning are:
 
 - A series of patches from Stephen Boyd removing the ARM local timer API.
 - Move of Qualcomm MSM IOMMU code to drivers/iommu.
 - Samsung PWM driver cleanups from Tomasz Figa, removing legacy PWM driver
   and switching over to the drivers/pwm one.
 - Removal of some unusued auto-generated headers for OMAP2+ (PRM/CM).
 
 There's also a move of a header file out of include/linux/i2c/ to
 platform_data, where it really belongs. It touches mostly ARM platform
 code for include changes so we took it through our tree.
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Merge tag 'cleanup-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc

Pull ARM SoC cleanups from Olof Johansson:
 "This branch contains code cleanups, moves and removals for 3.12.

  There's a large number of various cleanups, and a nice net removal of
  13500 lines of code.

  Highlights worth mentioning are:

   - A series of patches from Stephen Boyd removing the ARM local timer
     API.
   - Move of Qualcomm MSM IOMMU code to drivers/iommu.
   - Samsung PWM driver cleanups from Tomasz Figa, removing legacy PWM
     driver and switching over to the drivers/pwm one.
   - Removal of some unusued auto-generated headers for OMAP2+ (PRM/CM).

  There's also a move of a header file out of include/linux/i2c/ to
  platform_data, where it really belongs.  It touches mostly ARM
  platform code for include changes so we took it through our tree"

* tag 'cleanup-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (83 commits)
  ARM: OMAP2+: Add back the define for AM33XX_RST_GLOBAL_WARM_SW_MASK
  gpio: (gpio-pca953x) move header to linux/platform_data/
  arm: zynq: hotplug: Remove unreachable code
  ARM: SAMSUNG: Remove unnecessary exynos4_default_sdhci*()
  tegra: simplify use of devm_ioremap_resource
  ARM: SAMSUNG: Remove plat/regs-timer.h header
  ARM: SAMSUNG: Remove remaining uses of plat/regs-timer.h header
  ARM: SAMSUNG: Remove pwm-clock infrastructure
  ARM: SAMSUNG: Remove old PWM timer platform devices
  pwm: Remove superseded pwm-samsung-legacy driver
  ARM: SAMSUNG: Modify board files to use new PWM platform device
  ARM: SAMSUNG: Rework private data handling in dev-backlight
  pwm: Add new pwm-samsung driver
  ARM: mach-mvebu: remove redundant DT parsing and validation
  ARM: msm: Only compile io.c on platforms that use it
  iommu/msm: Move mach includes to iommu directory
  ARM: msm: Remove devices-iommu.c
  ARM: msm: Move mach/board.h contents to common.h
  ARM: msm: Migrate msm_timer to CLOCKSOURCE_OF_DECLARE
  ARM: msm: Remove TMR and TMR0 static mappings
  ...
2013-09-06 13:21:16 -07:00
Russell King 141b97433d Merge branches 'debug-choice', 'devel-stable' and 'misc' into for-linus 2013-09-05 10:34:15 +01:00
Will Deacon 9fc2105aea ARM: 7830/1: delay: don't bother reporting bogomips in /proc/cpuinfo
Now that we support a timer-backed delay loop, I'm quickly getting sick
and tired of people complaining that their beloved bogomips value has
decreased. You know who you are!

This patch removes the bogomips line from /proc/cpuinfo, based on the
reasoning that any program parsing this is already broken and, as such,
won't be further broken if the field is removed.

Acked-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-09-02 13:50:00 +01:00
Stephen Warren 2103f6cba6 ARM: 7807/1: kexec: validate CPU hotplug support
Architectures should fully validate whether kexec is possible as part of
machine_kexec_prepare(), so that user-space's kexec_load() operation can
report any problems. Performing validation in machine_kexec() itself is
too late, since it is not allowed to return.

Prior to this patch, ARM's machine_kexec() was testing after-the-fact
whether machine_kexec_prepare() was able to disable all but one CPU.
Instead, modify machine_kexec_prepare() to validate all conditions
necessary for machine_kexec_prepare()'s to succeed. BUG if the validation
succeeded, yet disabling the CPUs didn't actually work.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-08-13 20:23:18 +01:00
Olof Johansson 47dcd3563e Now that we have a generic arch hook for broadcast we can remove the local
timer API entirely. Doing so will reduce code in ARM core, reduce the
 architecture dependencies of our timer drivers, and simplify the code because
 we no longer go through an architecture layer that is essentially a hotplug
 notifier.
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Merge tag 'remove-local-timers' of git://git.kernel.org/pub/scm/linux/kernel/git/davidb/linux-msm into next/cleanup

From Stephen Boyd:

Now that we have a generic arch hook for broadcast we can remove the
local timer API entirely. Doing so will reduce code in ARM core, reduce
the architecture dependencies of our timer drivers, and simplify the code
because we no longer go through an architecture layer that is essentially
a hotplug notifier.

* tag 'remove-local-timers' of git://git.kernel.org/pub/scm/linux/kernel/git/davidb/linux-msm:
  ARM: smp: Remove local timer API
  clocksource: time-armada-370-xp: Divorce from local timer API
  clocksource: time-armada-370-xp: Fix sparse warning
  ARM: msm: Divorce msm_timer from local timer API
  ARM: PRIMA2: Divorce timer-marco from local timer API
  ARM: EXYNOS4: Divorce mct from local timer API
  ARM: OMAP2+: Divorce from local timer API
  ARM: smp_twd: Divorce smp_twd from local timer API
  ARM: smp: Remove duplicate dummy timer implementation

Resolved a large number of conflicts due to __cpuinit cleanups, etc.

Signed-off-by: Olof Johansson <olof@lixom.net>
2013-07-23 16:54:15 -07:00
Paul Gortmaker 8bd26e3a7e arm: delete __cpuinit/__CPUINIT usage from all ARM users
The __cpuinit type of throwaway sections might have made sense
some time ago when RAM was more constrained, but now the savings
do not offset the cost and complications.  For example, the fix in
commit 5e427ec2d0 ("x86: Fix bit corruption at CPU resume time")
is a good example of the nasty type of bugs that can be created
with improper use of the various __init prefixes.

After a discussion on LKML[1] it was decided that cpuinit should go
the way of devinit and be phased out.  Once all the users are gone,
we can then finally remove the macros themselves from linux/init.h.

Note that some harmless section mismatch warnings may result, since
notify_cpu_starting() and cpu_up() are arch independent (kernel/cpu.c)
and are flagged as __cpuinit  -- so if we remove the __cpuinit from
the arch specific callers, we will also get section mismatch warnings.
As an intermediate step, we intend to turn the linux/init.h cpuinit
related content into no-ops as early as possible, since that will get
rid of these warnings.  In any case, they are temporary and harmless.

This removes all the ARM uses of the __cpuinit macros from C code,
and all __CPUINIT from assembly code.  It also had two ".previous"
section statements that were paired off against __CPUINIT
(aka .section ".cpuinit.text") that also get removed here.

[1] https://lkml.org/lkml/2013/5/20/589

Cc: Russell King <linux@arm.linux.org.uk>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2013-07-14 19:36:52 -04:00
Russell King 3c0c01ab74 Merge branch 'devel-stable' into for-next
Conflicts:
	arch/arm/Makefile
	arch/arm/include/asm/glue-proc.h
2013-06-29 11:44:43 +01:00
Stephen Boyd 060fd3043e ARM: smp: Remove local timer API
There are no more users of this API, remove it.

Acked-by: Tony Lindgren <tony@atomide.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Cc: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2013-06-24 17:47:34 -07:00
Stephen Boyd 3d53ceeca7 ARM: smp: Remove duplicate dummy timer implementation
Drop ARM's version of the dummy timer now that we have a generic
implementation in drivers/clocksource.

Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Cc: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2013-06-24 17:45:58 -07:00
Russell King 3fbd55ec21 Merge branch 'for-rmk/lpae' of git://git.kernel.org/pub/scm/linux/kernel/git/will/linux into devel-stable
Conflicts:
	arch/arm/kernel/smp.c

Please pull these miscellaneous LPAE fixes I've been collecting for a while
now for 3.11. They've been tested and reviewed by quite a few people, and most
of the patches are pretty trivial. -- Will Deacon.
2013-06-18 20:11:32 +01:00
Stephen Warren 19ab428f4b ARM: 7759/1: decouple CPU offlining from reboot/shutdown
Add comments to machine_shutdown()/halt()/power_off()/restart() that
describe their purpose and/or requirements re: CPUs being active/not.

In machine_shutdown(), replace the call to smp_send_stop() with a call to
disable_nonboot_cpus(). This completely disables all but one CPU, thus
satisfying the requirement that only a single CPU be active for kexec.
Adjust Kconfig dependencies for this change.

In machine_halt()/power_off()/restart(), call smp_send_stop() directly,
rather than via machine_shutdown(); these functions don't need to
completely de-activate all CPUs using hotplug, but rather just quiesce
them.

Remove smp_kill_cpus(), and its call from smp_send_stop().
smp_kill_cpus() was indirectly calling smp_ops.cpu_kill() without calling
smp_ops.cpu_die() on the target CPUs first. At least some implementations
of smp_ops had issues with this; it caused cpu_kill() to hang on Tegra,
for example. Since smp_send_stop() is only used for shutdown, halt, and
power-off, there is no need to attempt any kind of CPU hotplug here.

Adjust Kconfig to reflect that machine_shutdown() (and hence kexec)
relies upon disable_nonboot_cpus(). However, this alone doesn't guarantee
that hotplug will work, or even that hotplug is implemented for a
particular piece of HW that a multi-platform zImage runs on. Hence, add
error-checking to machine_kexec() to determine whether it did work.

Suggested-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Tested-by:  Zhangfei Gao <zhangfei.gao@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-06-17 21:35:25 +01:00
Jonathan Austin eb08375ea6 ARM: mpu: add MPU initialisation for secondary cores
The MPU initialisation on the primary core is performed in two stages, one
minimal stage to ensure the CPU can boot and a second one after
sanity_check_meminfo. As the memory configuration is known by the time we
boot secondary cores only a single step is necessary, provided the values
for DRSR are passed to secondaries.

This patch implements this arrangement. The configuration generated for the
MPU regions is made available to the secondary core, which can then use the
asm MPU intialisation code to program a complete region configuration.

This is necessary for SMP configurations without an MMU, as the MPU
initialisation is the only way to ensure that memory is specified as
'shared'.

Signed-off-by: Jonathan Austin <jonathan.austin@arm.com>
Reviewed-by: Will Deacon <will.deacon@arm.com>
CC: Nicolas Pitre <nico@linaro.org>
2013-06-07 17:02:53 +01:00
Will Deacon c4a1f032ed ARM: nommu: do not initialise page tables in secondary_data structure
nommu systems do not require any page tables, so don't try to initialise
them when bringing up secondary cores.

Signed-off-by: Will Deacon <will.deacon@arm.com>
2013-06-07 17:02:43 +01:00
Cyril Chemparathy 4756dcbfd3 ARM: LPAE: accomodate >32-bit addresses for page table base
This patch redefines the early boot time use of the R4 register to steal a few
low order bits (ARCH_PGD_SHIFT bits) on LPAE systems.  This allows for up to
38-bit physical addresses.

Signed-off-by: Cyril Chemparathy <cyril@ti.com>
Signed-off-by: Vitaly Andrianov <vitalya@ti.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: Subash Patel <subash.rp@samsung.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2013-05-30 16:02:15 +01:00
Stephen Boyd aa03381046 ARM: smp: Drop RCU_NONIDLE usage in cpu_die()
Before f7b861b7a6 ("arm: Use generic idle loop") ARM would kill the
CPU within the rcu idle section.  Now that the rcu_idle_enter()/exit()
pair have been pushed lower down in the idle loop this is no longer true
and so using RCU_NONIDLE here is no longer necessary and also harmful
because RCU is not actually idle at this point.

Cc: Russell King <linux@arm.linux.org.uk>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-05-21 08:56:21 -07:00
Linus Torvalds 8546dc1d4b Merge branch 'for-linus' of git://git.linaro.org/people/rmk/linux-arm
Pull ARM updates from Russell King:
 "The major items included in here are:

   - MCPM, multi-cluster power management, part of the infrastructure
     required for ARMs big.LITTLE support.

   - A rework of the ARM KVM code to allow re-use by ARM64.

   - Error handling cleanups of the IS_ERR_OR_NULL() madness and fixes
     of that stuff for arch/arm

   - Preparatory patches for Cortex-M3 support from Uwe Kleine-König.

  There is also a set of three patches in here from Hugh/Catalin to
  address freeing of inappropriate page tables on LPAE.  You already
  have these from akpm, but they were already part of my tree at the
  time he sent them, so unfortunately they'll end up with duplicate
  commits"

* 'for-linus' of git://git.linaro.org/people/rmk/linux-arm: (77 commits)
  ARM: EXYNOS: remove unnecessary use of IS_ERR_VALUE()
  ARM: IMX: remove unnecessary use of IS_ERR_VALUE()
  ARM: OMAP: use consistent error checking
  ARM: cleanup: OMAP hwmod error checking
  ARM: 7709/1: mcpm: Add explicit AFLAGS to support v6/v7 multiplatform kernels
  ARM: 7700/2: Make cpu_init() notrace
  ARM: 7702/1: Set the page table freeing ceiling to TASK_SIZE
  ARM: 7701/1: mm: Allow arch code to control the user page table ceiling
  ARM: 7703/1: Disable preemption in broadcast_tlb*_a15_erratum()
  ARM: mcpm: provide an interface to set the SMP ops at run time
  ARM: mcpm: generic SMP secondary bringup and hotplug support
  ARM: mcpm_head.S: vlock-based first man election
  ARM: mcpm: Add baremetal voting mutexes
  ARM: mcpm: introduce helpers for platform coherency exit/setup
  ARM: mcpm: introduce the CPU/cluster power API
  ARM: multi-cluster PM: secondary kernel entry code
  ARM: cacheflush: add synchronization helpers for mixed cache state accesses
  ARM: cpu hotplug: remove majority of cache flushing from platforms
  ARM: smp: flush L1 cache in cpu_die()
  ARM: tegra: remove tegra specific cpu_disable()
  ...
2013-05-03 09:13:19 -07:00
Russell King 51acdfd1fa ARM: smp: flush L1 cache in cpu_die()
Flush the L1 cache for the CPU which is going down in cpu_die() so
that we don't end up with all platforms doing this.  This ensures
that any cache lines we own are pushed out before the cache becomes
inaccessible.

We may end up subsequently creating some dirty cache lines - for
example, with the complete() call, but this update must become
visible to other CPUs before __cpu_die() can proceed.  Subsequent
accesses from the platforms cpu_die() function should _not_ matter.

Also place a mb() after the complete() call to ensure that this is
visible to other CPUs.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-04-18 20:08:04 +01:00
Thomas Gleixner f7b861b7a6 arm: Use generic idle loop
Use the generic idle loop and replace enable/disable_hlt with the
respective core functions.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Reviewed-by: Cc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Cc: Magnus Damm <magnus.damm@gmail.com>
Cc: Russell King <linux@arm.linux.org.uk>
Tested-by: Kevin Hilman <khilman@linaro.org> # OMAP
Link: http://lkml.kernel.org/r/20130321215233.826238797@linutronix.de
2013-04-08 17:39:24 +02:00
Will Deacon 6f3d90e556 ARM: 7685/1: delay: use private ticks_per_jiffy field for timer-based delay ops
Commit 70264367a2 ("ARM: 7653/2: do not scale loops_per_jiffy when
using a constant delay clock") fixed a problem with our timer-based
delay loop, where loops_per_jiffy is scaled by cpufreq yet used directly
by the timer delay ops.

This patch fixes the problem in a more elegant way by keeping a private
ticks_per_jiffy field in the delay ops, independent of loops_per_jiffy
and therefore not subject to scaling. The loop-based delay continues to
use loops_per_jiffy directly, as it should.

Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-04-03 16:45:50 +01:00
Santosh Shilimkar f7db706b13 ARM: 7674/1: smp: Avoid dummy clockevent being preferred over real hardware clock-event
With recent arm broadcast time clean-up from Mark Rutland, the dummy
broadcast device is always registered with timer subsystem. And since
the rating of the dummy clock event is very high, it may be preferred
over a real clock event.

This is a change in behavior from past and not an intended one. So
reduce the rating of the dummy clock-event so that real clock-event
device is selected when available.

Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-03-15 17:19:31 +00:00
Will Deacon 89c7e4b8bb ARM: 7661/1: mm: perform explicit branch predictor maintenance when required
The ARM ARM requires branch predictor maintenance if, for a given ASID,
the instructions at a specific virtual address appear to change.

From the kernel's point of view, that means:

	- Changing the kernel's view of memory (e.g. switching to the
	  identity map)
	- ASID rollover (since ASIDs will be re-allocated to new tasks)

This patch adds explicit branch predictor maintenance when either of the
two conditions above are met.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-03-03 22:54:16 +00:00
Linus Torvalds 529e5fbcd8 Merge branch 'for-linus' of git://git.linaro.org/people/rmk/linux-arm
Pull late ARM updates from Russell King:
 "Here is the late set of ARM updates for this merge window; in here is:

   - The ARM parts of the broadcast timer support, core parts merged
     through tglx's tree.  This was left over from the previous merge to
     allow the dependency on tglx's tree to be resolved.

   - A fix to the VFP code which shows up on Raspberry Pi's, as well as
     fixing the fallout from a previous commit in this area.

   - A number of smaller fixes scattered throughout the ARM tree"

* 'for-linus' of git://git.linaro.org/people/rmk/linux-arm:
  ARM: Fix broken commit 0cc41e4a21 corrupting kernel messages
  ARM: fix scheduling while atomic warning in alignment handling code
  ARM: VFP: fix emulation of second VFP instruction
  ARM: 7656/1: uImage: Error out on build of multiplatform without LOADADDR
  ARM: 7640/1: memory: tegra_ahb_enable_smmu() depends on TEGRA_IOMMU_SMMU
  ARM: 7654/1: Preserve L_PTE_VALID in pte_modify()
  ARM: 7653/2: do not scale loops_per_jiffy when using a constant delay clock
  ARM: 7651/1: remove unused smp_timer_broadcast #define
2013-03-03 11:54:39 -08:00
Russell King 16af43fef8 Merge branches 'devel-stable', 'fixes' and 'mmci' into for-linus 2013-03-03 00:32:50 +00:00
Linus Torvalds 8b5628ab83 arm-soc: virtualization changes
This contains parts of the ARM KVM support that have dependencies on
 other patches merged through the arm-soc tree. In combination with
 patches coming through Russell's tree, this will finally add full
 support for the kernel based virtual machine on ARM,  which has
 been awaited for some time now.
 
 Further, we now have a separate platform for virtual machines
 and qemu booting that is used by both Xen and KVM, separating
 these from the Versatile Express reference implementation.
 Obviously, this new platform is multiplatform capable so it
 can be combined with existing machines in the same kernel.
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Merge tag 'virt' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc

Pull ARM virtualization changes:
 "This contains parts of the ARM KVM support that have dependencies on
  other patches merged through the arm-soc tree.  In combination with
  patches coming through Russell's tree, this will finally add full
  support for the kernel based virtual machine on ARM, which has been
  awaited for some time now.

  Further, we now have a separate platform for virtual machines and qemu
  booting that is used by both Xen and KVM, separating these from the
  Versatile Express reference implementation.  Obviously, this new
  platform is multiplatform capable so it can be combined with existing
  machines in the same kernel."

* tag 'virt' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (38 commits)
  ARM: arch_timer: include linux/errno.h
  arm: arch_timer: add missing inline in stub function
  ARM: KVM: arch_timers: Wire the init code and config option
  ARM: KVM: arch_timers: Add timer world switch
  ARM: KVM: arch_timers: Add guest timer core support
  ARM: KVM: Add VGIC configuration option
  ARM: KVM: VGIC initialisation code
  ARM: KVM: VGIC control interface world switch
  ARM: KVM: VGIC interrupt injection
  ARM: KVM: vgic: retire queued, disabled interrupts
  ARM: KVM: VGIC virtual CPU interface management
  ARM: KVM: VGIC distributor handling
  ARM: KVM: VGIC accept vcpu and dist base addresses from user space
  ARM: KVM: Initial VGIC infrastructure code
  ARM: KVM: Keep track of currently running vcpus
  KVM: ARM: Introduce KVM_ARM_SET_DEVICE_ADDR ioctl
  ARM: gic: add __ASSEMBLY__ guard to C definitions
  ARM: gic: define GICH offsets for VGIC support
  ARM: gic: add missing distributor defintions
  ARM: mach-virt: fixup machine descriptor after removal of sys_timer
  ...
2013-02-21 15:40:16 -08:00
Linus Torvalds b274776c54 arm-soc: cleanups
A large number of cleanups, all over the platforms. This is dominated
 largely by the Samsung platforms (s3c, s5p, exynos) and a few of the
 others moving code out of arch/arm into more appropriate subsystems.
 The clocksource and irqchip drivers are now abstracted to the point
 where platforms that are already cleaned up do not need to even specify
 the driver they use, it can all get configured from the device tree
 as we do for normal device drivers. The clocksource changes basically
 touch every single platform in the process.
 
 We further clean up the use of platform specific header files here,
 with the goal of turning more of the platforms over to being
 "multiplatform" enabled, which implies that they cannot expose
 their headers to architecture independent code any more.
 
 It is expected that no functional changes are part of the cleanup.
 The overall reduction in total code lines is mostly the result of
 removing broken and obsolete code.
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Merge tag 'cleanup' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc

Pull ARM SoC cleanups from Arnd Bergmann:
 "A large number of cleanups, all over the platforms.  This is dominated
  largely by the Samsung platforms (s3c, s5p, exynos) and a few of the
  others moving code out of arch/arm into more appropriate subsystems.

  The clocksource and irqchip drivers are now abstracted to the point
  where platforms that are already cleaned up do not need to even
  specify the driver they use, it can all get configured from the device
  tree as we do for normal device drivers.  The clocksource changes
  basically touch every single platform in the process.

  We further clean up the use of platform specific header files here,
  with the goal of turning more of the platforms over to being
  "multiplatform" enabled, which implies that they cannot expose their
  headers to architecture independent code any more.

  It is expected that no functional changes are part of the cleanup.
  The overall reduction in total code lines is mostly the result of
  removing broken and obsolete code."

* tag 'cleanup' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (133 commits)
  ARM: mvebu: correct gated clock documentation
  ARM: kirkwood: add missing include for nsa310
  ARM: exynos: move exynos4210-combiner to drivers/irqchip
  mfd: db8500-prcmu: update resource passing
  drivers/db8500-cpufreq: delete dangling include
  ARM: at91: remove NEOCORE 926 board
  sunxi: Cleanup the reset code and add meaningful registers defines
  ARM: S3C24XX: header mach/regs-mem.h local
  ARM: S3C24XX: header mach/regs-power.h local
  ARM: S3C24XX: header mach/regs-s3c2412-mem.h local
  ARM: S3C24XX: Remove plat-s3c24xx directory in arch/arm/
  ARM: S3C24XX: transform s3c2443 subirqs into new structure
  ARM: S3C24XX: modify s3c2443 irq init to initialize all irqs
  ARM: S3C24XX: move s3c2443 irq code to irq.c
  ARM: S3C24XX: transform s3c2416 irqs into new structure
  ARM: S3C24XX: modify s3c2416 irq init to initialize all irqs
  ARM: S3C24XX: move s3c2416 irq init to common irq code
  ARM: S3C24XX: Modify s3c_irq_wake to use the hwirq property
  ARM: S3C24XX: Move irq syscore-ops to irq-pm
  clocksource: always define CLOCKSOURCE_OF_DECLARE
  ...
2013-02-21 14:58:40 -08:00
Nicolas Pitre 70264367a2 ARM: 7653/2: do not scale loops_per_jiffy when using a constant delay clock
When udelay() is implemented using an architected timer, it is wrong
to scale loops_per_jiffy when changing the CPU clock frequency since
the timer clock remains constant.

The lpj should probably become an implementation detail relevant to
the CPU loop based delay routine only and more confined to it. In the
mean time this is the minimal fix needed to have expected delays with
the timer based implementation when cpufreq is also in use.

Reported-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Tested-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Liviu Dudau <Liviu.Dudau@arm.com>
Cc: stable@vger.kernel.org
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-02-21 13:25:36 +00:00
Mark Rutland 9664ffe6a1 ARM: 7651/1: remove unused smp_timer_broadcast #define
The assignment of clock_event_device::broadcast can be done by timer
core as of 12ad100046: "clockevents: Add generic timer broadcast
function", and the arm code moved over to this as of 3d06770eef: "arm:
Add generic timer broadcast support", but left a dangling #define when
!CONFIG_GENERIC_TIMER_BROADCAST.

This patch removes the now unused #define.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-02-13 23:41:04 +00:00
Olof Johansson 4f5c1c04f8 Merge branch 'irqchip/gic-vic-move' into next/virt 2013-02-11 09:05:29 -08:00
Mark Rutland 3d06770eef arm: Add generic timer broadcast support
Implement timer_broadcast for the arm architecture, allowing for the use
of clock_event_device_drivers decoupled from the timer tick broadcast
mechanism.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
2013-02-01 09:14:02 +00:00
Mark Rutland e2c501190c arm: Use generic timer broadcast receiver
Currently, the ARM backend must maintain a redundant list of timers for
the purpose of centralising timer broadcast functionality. This prevents
sharing timer drivers across architectures.

This patch moves the pain of dealing with timer broadcasts to the core
clockevents tick broadcast code, which already maintains its own list
of timers.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
2013-02-01 09:14:01 +00:00
Russell King 0a301110b7 ARM: smp: remove wrapper functions
Remove some silly wrapper functions which aren't really required:
	platform_smp_prepare_cpus
	platform_secondary_init
	platform_cpu_die

This simplifies the code.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-01-14 15:54:28 +00:00
Rob Herring b1cffebf10 ARM: GIC: remove direct use of gic_raise_softirq
In preparation of moving gic code to drivers/irqchip, remove the direct
platform dependencies on gic_raise_softirq. Move the setup of
smp_cross_call into the gic code and use arch_send_wakeup_ipi_mask
function to trigger wake-up IPIs.

Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Kukjin Kim <kgene.kim@samsung.com>
Cc: Sascha Hauer <kernel@pengutronix.de>
Cc: David Brown <davidb@codeaurora.org>
Cc: Daniel Walker <dwalker@fifo99.com>
Cc: Bryan Huntsman <bryanh@codeaurora.org>
Acked-by: Tony Lindgren <tony@atomide.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Magnus Damm <magnus.damm@gmail.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Shiraz Hashim <shiraz.hashim@st.com>
Acked-by: Stephen Warren <swarren@nvidia.com>
Cc: Srinidhi Kasagar <srinidhi.kasagar@stericsson.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Olof Johansson <olof@lixom.net>
2013-01-10 11:45:43 -06:00
Russell King 0fa5d3996d Merge branch 'devel-stable' into for-linus 2012-12-11 10:01:53 +00:00
Russell King 0b99cb7310 Merge branches 'cache-l2x0', 'fixes', 'hdrs', 'misc', 'mmci', 'vic' and 'warnings' into for-next 2012-12-11 00:20:18 +00:00
Nicolas Pitre 026b7c6bf0 ARM: 7590/1: /proc/interrupts: limit the display of IPIs to online CPUs only
This is what is done for the regular interrupts in kernel/irqs/proc.c
already, before calling arch_show_interrupts().  Not doing so for the
IPIs causes the column headers not to match with the content whenever
some CPUs are offline.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-12-07 11:45:28 +00:00
Rob Herring 14318efb32 ARM: 7587/1: implement optimized percpu variable access
Use the previously unused TPIDRPRW register to store percpu offsets.
TPIDRPRW is only accessible in PL1, so it can only be used in the kernel.

This replaces 2 loads with a mrc instruction for each percpu variable
access. With hackbench, the performance improvement is 1.4% on Cortex-A9
(highbank). Taking an average of 30 runs of "hackbench -l 1000" yields:

Before: 6.2191
After: 6.1348

Will Deacon reported similar delta on v6 with 11MPCore.

The asm "memory clobber" are needed here to ensure the percpu offset
gets reloaded. Testing by Will found that this would not happen in
__schedule() which is a bit of a special case as preemption is disabled
but the execution can move cores.

Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-12-03 11:16:36 +00:00
Lorenzo Pieralisi e8d432c9cf ARM: kernel: add MIDR to per-CPU information data
The advent of big.LITTLE ARM platforms requires the kernel to be able
to identify the MIDRs of all online CPUs upon request. MIDRs are stashed
at boot time so that kernel subsystems can detect the MIDR of online CPUs
by simply retrieving per-CPU data updated by all booted CPUs.

Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
2012-11-19 14:51:11 +00:00
Shawn Guo b62655f4c6 ARM: 7571/1: SMP: add function arch_send_wakeup_ipi_mask()
Add function arch_send_wakeup_ipi_mask(), so that platform code can
use it as an easy way to wake up cores that are in WFI.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-11-13 11:47:40 +00:00
Will Deacon 5f40b90972 ARM: 7559/1: smp: switch away from the idmap before updating init_mm.mm_count
When booting a secondary CPU, the primary CPU hands two sets of page
tables via the secondary_data struct:

	(1) swapper_pg_dir: a normal, cacheable, shared (if SMP) mapping
	    of the kernel image (i.e. the tables used by init_mm).

	(2) idmap_pgd: an uncached mapping of the .idmap.text ELF
	    section.

The idmap is generally used when enabling and disabling the MMU, which
includes early CPU boot. In this case, the secondary CPU switches to
swapper as soon as it enters C code:

	struct mm_struct *mm = &init_mm;
	unsigned int cpu = smp_processor_id();

	/*
	 * All kernel threads share the same mm context; grab a
	 * reference and switch to it.
	 */
	atomic_inc(&mm->mm_count);
	current->active_mm = mm;
	cpumask_set_cpu(cpu, mm_cpumask(mm));
	cpu_switch_mm(mm->pgd, mm);

This causes a problem on ARMv7, where the identity mapping is treated as
strongly-ordered leading to architecturally UNPREDICTABLE behaviour of
exclusive accesses, such as those used by atomic_inc.

This patch re-orders the secondary_start_kernel function so that we
switch to swapper before performing any exclusive accesses.

Cc: <stable@vger.kernel.org>
Cc: David McKay <david.mckay@st.com>
Reported-by: Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-10-22 15:33:51 +01:00
Russell King a0f0dd57f4 Merge branch 'fixes' into for-linus
Conflicts:
	arch/arm/kernel/smp.c
2012-10-11 10:55:04 +01:00