Commit graph

211 commits

Author SHA1 Message Date
Deepthi Dharwar
2c2e6ecfd0 powerpc/powernv/cpuidle: Back-end cpuidle driver for powernv platform.
Following patch ports the cpuidle framework for powernv
platform and also implements a cpuidle back-end powernv
idle driver calling on to power7_nap and snooze idle states.

Signed-off-by: Deepthi Dharwar <deepthi@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-01-29 17:02:24 +11:00
Deepthi Dharwar
3fa8cad82b powerpc/pseries/cpuidle: smt-snooze-delay cleanup.
smt-snooze-delay was designed to disable NAP state or delay the entry
to the NAP state prior to adoption of cpuidle framework. This
is per-cpu variable. With the coming of CPUIDLE framework,
states can be disabled on per-cpu basis using the cpuidle/enable
sysfs entry.

Also, with the coming of cpuidle driver each state's target residency
is per-driver unlike earlier which was per-device. Therefore,
the per-cpu sysfs smt-snooze-delay which decides the target residency
of the idle state on a particular cpu causes more confusion to the user
as we cannot have different smt-snooze-delay (target residency)
values for each cpu.

In the current code, smt-snooze-delay functionality is completely broken.
It makes sense to remove smt-snooze-delay from idle driver with the
coming of cpuidle framework.
However, sysfs files are retained as ppc64_util currently
utilises it. Once we fix ppc64_util, propose to clean
up the kernel code.

Signed-off-by: Deepthi Dharwar <deepthi@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-01-29 17:02:24 +11:00
Deepthi Dharwar
bf7f61f2df powerpc/pseries/cpuidle: Remove MAX_IDLE_STATE macro.
This patch removes the usage of MAX_IDLE_STATE macro
and dead code around it. The number of states
are determined at run time based on the cpuidle
state table selected on a given platform

Signed-off-by: Deepthi Dharwar <deepthi@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-01-29 17:02:23 +11:00
Deepthi Dharwar
12431c6497 powerpc/pseries/cpuidle: Make cpuidle-pseries backend driver a non-module.
Currently cpuidle-pseries backend driver cannot be
built as a module due to dependencies wrt cpuidle framework.
This patch removes all the module related code in the driver.

Signed-off-by: Deepthi Dharwar <deepthi@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-01-29 17:02:23 +11:00
Deepthi Dharwar
b69dbba059 powerpc/pseries/cpuidle: Use cpuidle_register() for initialisation.
This patch replaces the cpuidle driver and devices initialisation
calls with a single generic cpuidle_register() call
and also includes minor refactoring of the code around it.

Remove the cpu online check in snooze loop, as this code can
only locally run on a cpu only if it is online. Therefore,
this check is not required.

Signed-off-by: Deepthi Dharwar <deepthi@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-01-29 17:02:22 +11:00
Deepthi Dharwar
962e7bd497 powerpc/pseries/cpuidle: Move processor_idle.c to drivers/cpuidle.
Move the file from arch specific pseries/processor_idle.c
to drivers/cpuidle/cpuidle-pseries.c
Make the relevant Makefile and Kconfig changes.
Also, introduce Kconfig.powerpc in drivers/cpuidle
for all powerpc cpuidle drivers.

Signed-off-by: Deepthi Dharwar <deepthi@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-01-29 17:02:22 +11:00
Andre Przywara
5781532ebe ARM/cpuidle: remove __init tag from Calxeda cpuidle probe function
Commit 60a66e3700 changed the Calxeda
cpuidle driver to a platform driver, copying the __init tag from the
_init() to the newly used _probe() function. However, "probe should
not be __init." (Rob said ;-)
Remove the __init tag to fix a section mismatch in the Calxeda
cpuidle driver.

Signed-off-by: Andre Przywara <andre.przywara@linaro.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2013-12-30 11:55:20 +01:00
Konrad Rzeszutek Wilk
813e8e3d6a cpuidle: Check for dev before deregistering it.
If not, we could end up in the unfortunate situation where
we dereference a NULL pointer b/c we have cpuidle disabled.

This is the case when booting under Xen (which uses the
ACPI P/C states but disables the CPU idle driver) - and can
be easily reproduced when booting with cpuidle.off=1.

BUG: unable to handle kernel NULL pointer dereference at           (null)
IP: [<ffffffff8156db4a>] cpuidle_unregister_device+0x2a/0x90
.. snip..
Call Trace:
 [<ffffffff813b15b4>] acpi_processor_power_exit+0x3c/0x5c
 [<ffffffff813af0a9>] acpi_processor_stop+0x61/0xb6
 [<ffffffff814215bf>] __device_release_driver+0fffff81421653>] device_release_driver+0x23/0x30
 [<ffffffff81420ed8>] bus_remove_device+0x108/0x180
 [<ffffffff8141d9d9>] device_del+0x129/0x1c0
 [<ffffffff813cb4b0>] ? unregister_xenbus_watch+0x1f0/0x1f0
 [<ffffffff8141da8e>] device_unregister+0x1e/0x60
 [<ffffffff814243e9>] unregister_cpu+0x39/0x60
 [<ffffffff81019e03>] arch_unregister_cpu+0x23/0x30
 [<ffffffff813c3c51>] handle_vcpu_hotplug_event+0xc1/0xe0
 [<ffffffff813cb4f5>] xenwatch_thread+0x45/0x120
 [<ffffffff810af010>] ? abort_exclusive_wait+0xb0/0xb0
 [<ffffffff8108ec42>] kthread+0xd2/0xf0
 [<ffffffff8108eb70>] ? kthread_create_on_node+0x180/0x180
 [<ffffffff816ce17c>] ret_from_fork+0x7c/0xb0
 [<ffffffff8108eb70>] ? kthread_create_on_node+0x180/0x180

This problem also appears in 3.12 and could be a candidate for backport.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: All applicable <stable@vger.kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-12-03 22:05:22 +01:00
Linus Torvalds
f9300eaaac ACPI and power management updates for 3.13-rc1
- New power capping framework and the the Intel Running Average Power
    Limit (RAPL) driver using it from Srinivas Pandruvada and Jacob Pan.
 
  - Addition of the in-kernel switching feature to the arm_big_little
    cpufreq driver from Viresh Kumar and Nicolas Pitre.
 
  - cpufreq support for iMac G5 from Aaro Koskinen.
 
  - Baytrail processors support for intel_pstate from Dirk Brandewie.
 
  - cpufreq support for Midway/ECX-2000 from Mark Langsdorf.
 
  - ARM vexpress/TC2 cpufreq support from Sudeep KarkadaNagesha.
 
  - ACPI power management support for the I2C and SPI bus types from
    Mika Westerberg and Lv Zheng.
 
  - cpufreq core fixes and cleanups from Viresh Kumar, Srivatsa S Bhat,
    Stratos Karafotis, Xiaoguang Chen, Lan Tianyu.
 
  - cpufreq drivers updates (mostly fixes and cleanups) from Viresh Kumar,
    Aaro Koskinen, Jungseok Lee, Sudeep KarkadaNagesha, Lukasz Majewski,
    Manish Badarkhe, Hans-Christian Egtvedt, Evgeny Kapaev.
 
  - intel_pstate updates from Dirk Brandewie and Adrian Huang.
 
  - ACPICA update to version 20130927 includig fixes and cleanups and
    some reduction of divergences between the ACPICA code in the kernel
    and ACPICA upstream in order to improve the automatic ACPICA patch
    generation process.  From Bob Moore, Lv Zheng, Tomasz Nowicki,
    Naresh Bhat, Bjorn Helgaas, David E Box.
 
  - ACPI IPMI driver fixes and cleanups from Lv Zheng.
 
  - ACPI hotplug fixes and cleanups from Bjorn Helgaas, Toshi Kani,
    Zhang Yanfei, Rafael J Wysocki.
 
  - Conversion of the ACPI AC driver to the platform bus type and
    multiple driver fixes and cleanups related to ACPI from Zhang Rui.
 
  - ACPI processor driver fixes and cleanups from Hanjun Guo, Jiang Liu,
    Bartlomiej Zolnierkiewicz, Mathieu Rhéaume, Rafael J Wysocki.
 
  - Fixes and cleanups and new blacklist entries related to the ACPI
    video support from Aaron Lu, Felipe Contreras, Lennart Poettering,
    Kirill Tkhai.
 
  - cpuidle core cleanups from Viresh Kumar and Lorenzo Pieralisi.
 
  - cpuidle drivers fixes and cleanups from Daniel Lezcano, Jingoo Han,
    Bartlomiej Zolnierkiewicz, Prarit Bhargava.
 
  - devfreq updates from Sachin Kamat, Dan Carpenter, Manish Badarkhe.
 
  - Operation Performance Points (OPP) core updates from Nishanth Menon.
 
  - Runtime power management core fix from Rafael J Wysocki and update
    from Ulf Hansson.
 
  - Hibernation fixes from Aaron Lu and Rafael J Wysocki.
 
  - Device suspend/resume lockup detection mechanism from Benoit Goby.
 
  - Removal of unused proc directories created for various ACPI drivers
    from Lan Tianyu.
 
  - ACPI LPSS driver fix and new device IDs for the ACPI platform scan
    handler from Heikki Krogerus and Jarkko Nikula.
 
  - New ACPI _OSI blacklist entry for Toshiba NB100 from Levente Kurusa.
 
  - Assorted fixes and cleanups related to ACPI from Andy Shevchenko,
    Al Stone, Bartlomiej Zolnierkiewicz, Colin Ian King, Dan Carpenter,
    Felipe Contreras, Jianguo Wu, Lan Tianyu, Yinghai Lu, Mathias Krause,
    Liu Chuansheng.
 
  - Assorted PM fixes and cleanups from Andy Shevchenko, Thierry Reding,
    Jean-Christophe Plagniol-Villard.
 
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Merge tag 'pm+acpi-3.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull ACPI and power management updates from Rafael J Wysocki:

 - New power capping framework and the the Intel Running Average Power
   Limit (RAPL) driver using it from Srinivas Pandruvada and Jacob Pan.

 - Addition of the in-kernel switching feature to the arm_big_little
   cpufreq driver from Viresh Kumar and Nicolas Pitre.

 - cpufreq support for iMac G5 from Aaro Koskinen.

 - Baytrail processors support for intel_pstate from Dirk Brandewie.

 - cpufreq support for Midway/ECX-2000 from Mark Langsdorf.

 - ARM vexpress/TC2 cpufreq support from Sudeep KarkadaNagesha.

 - ACPI power management support for the I2C and SPI bus types from Mika
   Westerberg and Lv Zheng.

 - cpufreq core fixes and cleanups from Viresh Kumar, Srivatsa S Bhat,
   Stratos Karafotis, Xiaoguang Chen, Lan Tianyu.

 - cpufreq drivers updates (mostly fixes and cleanups) from Viresh
   Kumar, Aaro Koskinen, Jungseok Lee, Sudeep KarkadaNagesha, Lukasz
   Majewski, Manish Badarkhe, Hans-Christian Egtvedt, Evgeny Kapaev.

 - intel_pstate updates from Dirk Brandewie and Adrian Huang.

 - ACPICA update to version 20130927 includig fixes and cleanups and
   some reduction of divergences between the ACPICA code in the kernel
   and ACPICA upstream in order to improve the automatic ACPICA patch
   generation process.  From Bob Moore, Lv Zheng, Tomasz Nowicki, Naresh
   Bhat, Bjorn Helgaas, David E Box.

 - ACPI IPMI driver fixes and cleanups from Lv Zheng.

 - ACPI hotplug fixes and cleanups from Bjorn Helgaas, Toshi Kani, Zhang
   Yanfei, Rafael J Wysocki.

 - Conversion of the ACPI AC driver to the platform bus type and
   multiple driver fixes and cleanups related to ACPI from Zhang Rui.

 - ACPI processor driver fixes and cleanups from Hanjun Guo, Jiang Liu,
   Bartlomiej Zolnierkiewicz, Mathieu Rhéaume, Rafael J Wysocki.

 - Fixes and cleanups and new blacklist entries related to the ACPI
   video support from Aaron Lu, Felipe Contreras, Lennart Poettering,
   Kirill Tkhai.

 - cpuidle core cleanups from Viresh Kumar and Lorenzo Pieralisi.

 - cpuidle drivers fixes and cleanups from Daniel Lezcano, Jingoo Han,
   Bartlomiej Zolnierkiewicz, Prarit Bhargava.

 - devfreq updates from Sachin Kamat, Dan Carpenter, Manish Badarkhe.

 - Operation Performance Points (OPP) core updates from Nishanth Menon.

 - Runtime power management core fix from Rafael J Wysocki and update
   from Ulf Hansson.

 - Hibernation fixes from Aaron Lu and Rafael J Wysocki.

 - Device suspend/resume lockup detection mechanism from Benoit Goby.

 - Removal of unused proc directories created for various ACPI drivers
   from Lan Tianyu.

 - ACPI LPSS driver fix and new device IDs for the ACPI platform scan
   handler from Heikki Krogerus and Jarkko Nikula.

 - New ACPI _OSI blacklist entry for Toshiba NB100 from Levente Kurusa.

 - Assorted fixes and cleanups related to ACPI from Andy Shevchenko, Al
   Stone, Bartlomiej Zolnierkiewicz, Colin Ian King, Dan Carpenter,
   Felipe Contreras, Jianguo Wu, Lan Tianyu, Yinghai Lu, Mathias Krause,
   Liu Chuansheng.

 - Assorted PM fixes and cleanups from Andy Shevchenko, Thierry Reding,
   Jean-Christophe Plagniol-Villard.

* tag 'pm+acpi-3.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (386 commits)
  cpufreq: conservative: fix requested_freq reduction issue
  ACPI / hotplug: Consolidate deferred execution of ACPI hotplug routines
  PM / runtime: Use pm_runtime_put_sync() in __device_release_driver()
  ACPI / event: remove unneeded NULL pointer check
  Revert "ACPI / video: Ignore BIOS initial backlight value for HP 250 G1"
  ACPI / video: Quirk initial backlight level 0
  ACPI / video: Fix initial level validity test
  intel_pstate: skip the driver if ACPI has power mgmt option
  PM / hibernate: Avoid overflow in hibernate_preallocate_memory()
  ACPI / hotplug: Do not execute "insert in progress" _OST
  ACPI / hotplug: Carry out PCI root eject directly
  ACPI / hotplug: Merge device hot-removal routines
  ACPI / hotplug: Make acpi_bus_hot_remove_device() internal
  ACPI / hotplug: Simplify device ejection routines
  ACPI / hotplug: Fix handle_root_bridge_removal()
  ACPI / hotplug: Refuse to hot-remove all objects with disabled hotplug
  ACPI / scan: Start matching drivers after trying scan handlers
  ACPI: Remove acpi_pci_slot_init() headers from internal.h
  ACPI / blacklist: fix name of ThinkPad Edge E530
  PowerCap: Fix build error with option -Werror=format-security
  ...

Conflicts:
	arch/arm/mach-omap2/opp.c
	drivers/Kconfig
	drivers/spi/spi.c
2013-11-14 13:41:48 +09:00
Viresh Kumar
f60e230f6b cpuidle: remove cpuidle_unregister_governor()
cpuidle_unregister_governor() and cpuidle_replace_governor() aren't
used anymore and can be removed. They were used by cpufreq governors
earlier, but since the governors can't be compiled as modules any
more, these two functions aren't necessary.

Suggested-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-10-30 01:21:24 +01:00
Viresh Kumar
d7c7f10326 cpuidle: don't call poll_idle_init() for every cpu
poll_idle_init() just initializes drv->states[0] and so that is
required to be done only once for each driver.  Currently, it is
called from cpuidle_enable_device() which is called for every CPU
that the driver supports.  That is not required, so move it to a
better place and call it from __cpuidle_register_driver() so that
the initialization is carried out only once.

Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-10-30 01:21:23 +01:00
Viresh Kumar
1f6b9f74ee cpuidle: use drv instead of cpuidle_driver in show_current_driver()
Instances of "struct cpuidle_driver *" are consistently named as "drv"
in the cpuidle core except in show_current_driver().

Make that function use variable naming consistent with the rest of the
code.

[rjw: Changelog]
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-10-30 01:21:23 +01:00
Viresh Kumar
0d09d31256 cpuidle: call cpuidle_get_driver() from after taking cpuidle_driver_lock
There are a few cpuidle_get_driver() calls that aren't made under
cpuidle_driver_lock which is incorrect.

Fix them by calling cpuidle_get_driver() after taking cpuidle_driver_lock.

Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-10-30 01:21:23 +01:00
Viresh Kumar
6d281e97a1 cpuidle: replace multiline statements with single line in cpuidle_idle_call()
Few statements in cpuidle_idle_call() are broken into multiple lines,
although that isn't really necessary. Convert those to single line.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-10-30 01:21:23 +01:00
Viresh Kumar
fb11c9c63f cpuidle: reduce code duplication inside cpuidle_idle_call()
We are doing this twice in cpuidle_idle_call() routine:
	drv->states[next_state].flags & CPUIDLE_FLAG_TIMER_STOP

Would be better if we actually store this in a local variable and
use that. That reduces code duplication and likely makes this piece
of code run faster (in case the compiler wasn't able to optimize it
earlier)

[rjw: Cast the result of bitwise AND to bool explicitly using !!]
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-10-30 01:21:22 +01:00
Viresh Kumar
9b29a86f04 cpuidle: merge two if() statements for checking error cases
Two checks cpuidle_idle_call() cause the same error code to be
returned if they fail, so merge them for clarity.

[rjw: Changelog]
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-10-30 01:21:22 +01:00
Viresh Kumar
47182668ca cpuidle: rearrange __cpuidle_register_device() to keep minimal exit points
This patch rearranges __cpuidle_register_device() a bit in order to
reduce the number of exit points in that function.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-10-30 01:21:22 +01:00
Viresh Kumar
b171a85648 cpuidle: rearrange code in __cpuidle_driver_init()
This is trivial patch that just reorders a few statements in
__cpuidle_driver_init() routine so that we don't need both 'continue'
and 'break' in the for loop. Functionally it shouldn't change anything.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-10-30 01:21:22 +01:00
Viresh Kumar
e437f3e373 cpuidle: make __cpuidle_driver_init() return void
The only value returned by __cpuidle_driver_init() is 0, so it
very well may be a void function.

[rjw: Changelog]
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-10-30 01:21:22 +01:00
Viresh Kumar
267d4bf8ee cpuidle: make __cpuidle_device_init() return void
The only value returned by __cpuidle_device_init() is 0, so it very
well may be a void function.  Make that happen.

[rjw: Changelog]
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-10-30 01:21:21 +01:00
Viresh Kumar
caf4a36e81 cpuidle: Fix comments in cpuidle core
Some comments in cpuidle core files contain trivial mistakes.
This patch fixes them.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-10-30 01:21:21 +01:00
Daniel Lezcano
1ce3c48e6c ARM: at91: cpuidle: Move driver to drivers/cpuidle
As the cpuidle driver code has no more the dependency with the pm code, the
'standby' callback being passed as a parameter to the device's platform data,
we can move the cpuidle driver in the drivers/cpuidle directory.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>

Conflicts:

	drivers/cpuidle/Kconfig.arm
	drivers/cpuidle/Makefile
2013-10-16 23:49:35 +02:00
Daniel Lezcano
2c2b24d9c3 ARM: ux500: cpuidle: fix section mismatch
The dbx500_cpuidle_probe is tagged as an __init section but the variable
dbx500_cpuidle_plat_driver is not.

The dbx500_cpuidle_probe could not be declared as __init because of macro
module_platform_driver builds the exit function, tags as __exit and this one
refers to the dbx500_cpuidle_plat_driver which is an __initdata.

That leads to a section mismatch.

Fix it by removing the __init tag for the probe function.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
2013-10-07 16:47:07 +02:00
Daniel Lezcano
3e8ceca6c7 ARM: zynq: cpuidle: convert to platform driver
As the ux500 and the kirkwood driver, make the zynq driver a platform driver

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Michal Simek <michal.simek@xilinx.com>
Tested-by: Soren Brinkmann <soren.brinkmann@xilinx.com>
2013-10-07 16:46:59 +02:00
Daniel Lezcano
4aa88fbe6d ARM: zynq: cpuidle: Remove useless compatibility string
All zynq platforms have this compatibility string and there is no any other
clone.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Michal Simek <michal.simek@xilinx.com>
2013-10-07 16:46:56 +02:00
Lorenzo Pieralisi
3880d21450 drivers: cpuidle: rename ARM big.LITTLE driver config and makefile entries
Following the reorganization of CPU idle drivers configurations into an ARM
specific Kconfig, the existing idle drivers Kconfig entries were renamed and
moved to the Kconfig.arm file. Makefile entries were updated accordingly.

This patch renames the entries in Kconfig.arm and makefile to make the newly
added big.LITTLE CPUidle driver compliant with the new naming convention.

Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2013-10-07 16:46:54 +02:00
Rob Herring
a410146c3e cpuidle: calxeda: add support to use PSCI calls
This updates the Calxeda cpuidle driver to use PSCI calls to powergate
cores. This also enables cpuidle for the ECX-2000.

This could possibly become a generic PSCI driver, but there are no other
PSCI users in the kernel other than mach-virt.

Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: linux-pm@vger.kernel.org
2013-10-01 16:30:56 -05:00
Daniel Lezcano
60a66e3700 ARM: highbank: cpuidle: convert to platform driver
As the ux500 and the kirkwood driver, make the calxeda driver a platform driver

[Compiled only]

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
2013-10-01 16:30:20 -05:00
Rob Herring
34a5eeb202 cpuidle: calxeda: add cpu_pm_enter/exit calls
Wnen powergating the core, we need to call cpu pm notifiers to save VFP
state (!SMP only) and resetting the breakpoint h/w.

Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: linux-pm@vger.kernel.org
2013-10-01 16:30:18 -05:00
Linus Torvalds
02b9735c12 ACPI and power management fixes for 3.12-rc1
1) ACPI-based PCI hotplug (ACPIPHP) fixes related to spurious events
 
   After the recent ACPIPHP changes we've seen some interesting breakage
   on a system that triggers device check notifications during boot for
   non-existing devices.  Although those notifications are really
   spurious, we should be able to deal with them nevertheless and that
   shouldn't introduce too much overhead.  Four commits to make that
   work properly.
 
  2) Memory hotplug and hibernation mutual exclusion rework
 
   This was maent to be a cleanup, but it happens to fix a classical
   ABBA deadlock between system suspend/hibernation and ACPI memory
   hotplug which is possible if they are started roughly at the same
   time.  Three commits rework memory hotplug so that it doesn't
   acquire pm_mutex and make hibernation use device_hotplug_lock
   which prevents it from racing with memory hotplug.
 
  3) ACPI Intel LPSS (Low-Power Subsystem) driver crash fix
 
   The ACPI LPSS driver crashes during boot on Apple Macbook Air with
   Haswell that has slightly unusual BIOS configuration in which one
   of the LPSS device's _CRS method doesn't return all of the information
   expected by the driver.  Fix from Mika Westerberg, for stable.
 
  4) ACPICA fix related to Store->ArgX operation
 
   AML interpreter fix for obscure breakage that causes AML to be
   executed incorrectly on some machines (observed in practice).  From
   Bob Moore.
 
  5) ACPI core fix for PCI ACPI device objects lookup
 
   There still are cases in which there is more than one ACPI device
   object matching a given PCI device and we don't choose the one that
   the BIOS expects us to choose, so this makes the lookup take more
   criteria into account in those cases.
 
  6) Fix to prevent cpuidle from crashing in some rare cases
 
   If the result of cpuidle_get_driver() is NULL, which can happen on
   some systems, cpuidle_driver_ref() will crash trying to use that
   pointer and the Daniel Fu's fix prevents that from happening.
 
  7) cpufreq fixes related to CPU hotplug
 
   Stephen Boyd reported a number of concurrency problems with cpufreq
   related to CPU hotplug which are addressed by a series of fixes
   from Srivatsa S Bhat and Viresh Kumar.
 
  8) cpufreq fix for time conversion in time_in_state attribute
 
   Time conversion carried out by cpufreq when user space attempts to
   read /sys/devices/system/cpu/cpu*/cpufreq/stats/time_in_state won't
   work correcty if cputime_t doesn't map directly to jiffies.  Fix
   from Andreas Schwab.
 
  9) Revert of a troublesome cpufreq commit
 
   Commit 7c30ed5 (cpufreq: make sure frequency transitions are
   serialized) was intended to address some known concurrency problems
   in cpufreq related to the ordering of transitions, but unfortunately
   it introduced several problems of its own, so I decided to revert it
   now and address the original problems later in a more robust way.
 
 10) Intel Haswell CPU models for intel_pstate from Nell Hardcastle.
 
 11) cpufreq fixes related to system suspend/resume
 
   The recent cpufreq changes that made it preserve CPU sysfs attributes
   over suspend/resume cycles introduced a possible NULL pointer
   dereference that caused it to crash during the second attempt to
   suspend.  Three commits from Srivatsa S Bhat fix that problem and a
   couple of related issues.
 
 12) cpufreq locking fix
 
   cpufreq_policy_restore() should acquire the lock for reading, but
   it acquires it for writing.  Fix from Lan Tianyu.
 
 /
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Merge tag 'pm+acpi-fixes-3.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull ACPI and power management fixes from Rafael Wysocki:
 "All of these commits are fixes that have emerged recently and some of
  them fix bugs introduced during this merge window.

  Specifics:

   1) ACPI-based PCI hotplug (ACPIPHP) fixes related to spurious events

      After the recent ACPIPHP changes we've seen some interesting
      breakage on a system that triggers device check notifications
      during boot for non-existing devices.  Although those
      notifications are really spurious, we should be able to deal with
      them nevertheless and that shouldn't introduce too much overhead.
      Four commits to make that work properly.

   2) Memory hotplug and hibernation mutual exclusion rework

      This was maent to be a cleanup, but it happens to fix a classical
      ABBA deadlock between system suspend/hibernation and ACPI memory
      hotplug which is possible if they are started roughly at the same
      time.  Three commits rework memory hotplug so that it doesn't
      acquire pm_mutex and make hibernation use device_hotplug_lock
      which prevents it from racing with memory hotplug.

   3) ACPI Intel LPSS (Low-Power Subsystem) driver crash fix

      The ACPI LPSS driver crashes during boot on Apple Macbook Air with
      Haswell that has slightly unusual BIOS configuration in which one
      of the LPSS device's _CRS method doesn't return all of the
      information expected by the driver.  Fix from Mika Westerberg, for
      stable.

   4) ACPICA fix related to Store->ArgX operation

      AML interpreter fix for obscure breakage that causes AML to be
      executed incorrectly on some machines (observed in practice).
      From Bob Moore.

   5) ACPI core fix for PCI ACPI device objects lookup

      There still are cases in which there is more than one ACPI device
      object matching a given PCI device and we don't choose the one
      that the BIOS expects us to choose, so this makes the lookup take
      more criteria into account in those cases.

   6) Fix to prevent cpuidle from crashing in some rare cases

      If the result of cpuidle_get_driver() is NULL, which can happen on
      some systems, cpuidle_driver_ref() will crash trying to use that
      pointer and the Daniel Fu's fix prevents that from happening.

   7) cpufreq fixes related to CPU hotplug

      Stephen Boyd reported a number of concurrency problems with
      cpufreq related to CPU hotplug which are addressed by a series of
      fixes from Srivatsa S Bhat and Viresh Kumar.

   8) cpufreq fix for time conversion in time_in_state attribute

      Time conversion carried out by cpufreq when user space attempts to
      read /sys/devices/system/cpu/cpu*/cpufreq/stats/time_in_state
      won't work correcty if cputime_t doesn't map directly to jiffies.
      Fix from Andreas Schwab.

   9) Revert of a troublesome cpufreq commit

      Commit 7c30ed5 (cpufreq: make sure frequency transitions are
      serialized) was intended to address some known concurrency
      problems in cpufreq related to the ordering of transitions, but
      unfortunately it introduced several problems of its own, so I
      decided to revert it now and address the original problems later
      in a more robust way.

  10) Intel Haswell CPU models for intel_pstate from Nell Hardcastle.

  11) cpufreq fixes related to system suspend/resume

      The recent cpufreq changes that made it preserve CPU sysfs
      attributes over suspend/resume cycles introduced a possible NULL
      pointer dereference that caused it to crash during the second
      attempt to suspend.  Three commits from Srivatsa S Bhat fix that
      problem and a couple of related issues.

  12) cpufreq locking fix

      cpufreq_policy_restore() should acquire the lock for reading, but
      it acquires it for writing.  Fix from Lan Tianyu"

* tag 'pm+acpi-fixes-3.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (25 commits)
  cpufreq: Acquire the lock in cpufreq_policy_restore() for reading
  cpufreq: Prevent problems in update_policy_cpu() if last_cpu == new_cpu
  cpufreq: Restructure if/else block to avoid unintended behavior
  cpufreq: Fix crash in cpufreq-stats during suspend/resume
  intel_pstate: Add Haswell CPU models
  Revert "cpufreq: make sure frequency transitions are serialized"
  cpufreq: Use signed type for 'ret' variable, to store negative error values
  cpufreq: Remove temporary fix for race between CPU hotplug and sysfs-writes
  cpufreq: Synchronize the cpufreq store_*() routines with CPU hotplug
  cpufreq: Invoke __cpufreq_remove_dev_finish() after releasing cpu_hotplug.lock
  cpufreq: Split __cpufreq_remove_dev() into two parts
  cpufreq: Fix wrong time unit conversion
  cpufreq: serialize calls to __cpufreq_governor()
  cpufreq: don't allow governor limits to be changed when it is disabled
  ACPI / bind: Prefer device objects with _STA to those without it
  ACPI / hotplug / PCI: Avoid parent bus rescans on spurious device checks
  ACPI / hotplug / PCI: Use _OST to notify firmware about notify status
  ACPI / hotplug / PCI: Avoid doing too much for spurious notifies
  ACPICA: Fix for a Store->ArgX when ArgX contains a reference to a field.
  ACPI / hotplug / PCI: Don't trim devices before scanning the namespace
  ...
2013-09-12 11:22:45 -07:00
Linus Torvalds
a35c6322e5 ARM: SoC drivers for v3.12
This branch contains ARM SoC related driver updates for v3.12.  The
 only thing this cycle are core PM updates and CPUidle support for
 ARM's TC2 big.LITTLE development platform.
 
 Conflicts:
 
 One cleanup/reorg conflict with a new entry in
 drivers/cpuidle/Makefile.  Append the new entry after the existing
 ones.  A follow up patch for v3.12-rc will make the new entry conform
 to the cleanup/reorg.
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Merge tag 'drivers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc

Pull ARM SoC driver update from Kevin Hilman:
 "This contains the ARM SoC related driver updates for v3.12.  The only
  thing this cycle are core PM updates and CPUidle support for ARM's TC2
  big.LITTLE development platform"

* tag 'drivers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
  cpuidle: big.LITTLE: vexpress-TC2 CPU idle driver
  ARM: vexpress: tc2: disable GIC CPU IF in tc2_pm_suspend
  drivers: irq-chip: irq-gic: introduce gic_cpu_if_down()
2013-09-09 16:08:13 -07:00
Daniel Fu
3b9c10e980 cpuidle: Check the result of cpuidle_get_driver() against NULL
If the current CPU has no cpuidle driver, drv will be NULL in
cpuidle_driver_ref().  Check if that is the case before trying
to bump up the driver's refcount to prevent the kernel from
crashing.

[rjw: Subject and changelog]
Signed-off-by: Daniel Fu <danifu@nvidia.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-30 21:53:41 +02:00
Colin Cross
9e19b73c30 cpuidle: coupled: fix race condition between pokes and safe state
The coupled cpuidle waiting loop clears pending pokes before
entering the safe state.  If a poke arrives just before the
pokes are cleared, but after the while loop condition checks,
the poke will be lost and the cpu will stay in the safe state
until another interrupt arrives.  This may cause the cpu that
sent the poke to spin in the ready loop with interrupts off
until another cpu receives an interrupt, and if no other cpus
have interrupts routed to them it can spin forever.

Change the return value of cpuidle_coupled_clear_pokes to
return if a poke was cleared, and move the need_resched()
checks into the callers.  In the waiting loop, if
a poke was cleared restart the loop to repeat the while
condition checks.

Reported-by: Neil Zhang <zhangwm@marvell.com>
Signed-off-by: Colin Cross <ccross@android.com>
Cc: 3.6+ <stable@vger.kernel.org> # 3.6+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-29 22:15:34 +02:00
Colin Cross
f983827bcb cpuidle: coupled: abort idle if pokes are pending
Joseph Lo <josephl@nvidia.com> reported a lockup on Tegra20 caused
by a race condition in coupled cpuidle.  When two or more cpus
enter idle at the same time, the first cpus to arrive may go to the
ready loop without processing pending pokes from the last cpu to
arrive.

This patch adds a check for pending pokes once all cpus have been
synchronized in the ready loop and resets the coupled state and
retries if any cpus failed to handle their pending poke.

Retrying on all cpus may trigger the same issue again, so this patch
also adds a check to ensure that each cpu has received at least one
poke between when it enters the waiting loop and when it moves on to
the ready loop.

Reported-and-tested-by: Joseph Lo <josephl@nvidia.com>
Tested-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Colin Cross <ccross@android.com>
Cc: 3.6+ <stable@vger.kernel.org> # 3.6+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-29 22:15:04 +02:00
Colin Cross
59e9985611 cpuidle: coupled: disable interrupts after entering safe state
Calling cpuidle_enter_state is expected to return with interrupts
enabled, but interrupts must be disabled before starting the
ready loop synchronization stage.  Call local_irq_disable after
each call to cpuidle_enter_state for the safe state.

Tested-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Colin Cross <ccross@android.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-29 22:11:38 +02:00
Olof Johansson
aaf75e454c Merge branch 'cpuidle/biglittle' into next/drivers
From Lorenzo Pieralisi:
This patch series contains:

- GIC driver update to add a method to disable the GIC CPU IF
- TC2 MCPM update to add GIC CPU disabling to suspend method
- TC2 CPU idle big.LITTLE driver

* cpuidle/biglittle:
  cpuidle: big.LITTLE: vexpress-TC2 CPU idle driver
  ARM: vexpress: tc2: disable GIC CPU IF in tc2_pm_suspend
  drivers: irq-chip: irq-gic: introduce gic_cpu_if_down()
  ARM: vexpress/TC2: implement PM suspend method
  ARM: vexpress/TC2: basic PM support
  ARM: vexpress: Add SCC to V2P-CA15_A7's device tree
  ARM: vexpress/TC2: add Serial Power Controller (SPC) support
  ARM: vexpress/dcscb: fix cache disabling sequences

Signed-off-by: Olof Johansson <olof@lixom.net>
2013-08-28 11:29:18 -07:00
Lorenzo Pieralisi
14d2c34cfa cpuidle: big.LITTLE: vexpress-TC2 CPU idle driver
The big.LITTLE architecture is composed of two clusters of cpus. One cluster
contains less powerful but more energy efficient processors and the other
cluster groups the powerful but energy-intensive cpus.

The TC2 testchip implements two clusters of CPUs (A7 and A15 clusters in
a big.LITTLE configuration) connected through a CCI interconnect that manages
coherency of their respective L2 caches and intercluster distributed
virtual memory messages (DVM).

TC2 testchip integrates a power controller that manages cores resets, wake-up
IRQs and cluster low-power states. Power states are managed at cluster
level, which means that voltage is removed from a cluster iff all cores
in a cluster are in a wfi state. Single cores can enter a reset state
which is identical to wfi in terms of power consumption but simplifies the
way cluster states are entered.

This patch provides a multiple driver CPU idle implementation for TC2
which paves the way for a generic big.LITTLE idle driver for all
upcoming big.LITTLE based systems on chip.

The driver relies on the MCPM infrastructure to coordinate and manage
core power states; in particular MCPM allows to suspend specific cores
and hides the CPUs coordination required to shut-down clusters of CPUs.

Power down sequences for the respective clusters are implemented in the
MCPM TC2 backend, with all code needed to clean caches and exit coherency.

The multiple driver CPU idle infrastructure allows to define different
C-states for big and little cores, determined at boot by checking the
part id of the possible CPUs and initializing the respective logical
masks in the big and little drivers.

Current big.little systems are composed of A7 and A15 clusters, as
implemented in TC2, but in the future that may change and the driver
will have evolve to retrieve what is a 'big' cpu and what is a 'little'
cpu in order to build the correct topology.

Cc: Kevin Hilman <khilman@linaro.org>
Cc: Amit Kucheria <amit.kucheria@linaro.org>
Cc: Olof Johansson <olof@lixom.net>
Cc: Nicolas Pitre <nicolas.pitre@linaro.org>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Olof Johansson <olof@lixom.net>
2013-08-28 11:28:51 -07:00
Tuukka Tikkanen
51f245b895 cpuidle: Change struct menu_device field types
Field predicted_us value can never exceed expected_us value, but it has
a potentially larger type. As there is no need for additional 32 bits of
zeroes on 32 bit plaforms, change the type of predicted_us to match the
type of expected_us.

Field correction_factor is used to store a value that cannot exceed the
product of RESOLUTION and DECAY (default 1024*8 = 8192). The constants
cannot in practice be incremented to such values, that they'd overflow
unsigned int even on 32 bit systems, so the type is changed to avoid
unnecessary 64 bit arithmetic on 32 bit systems.

One multiplication of (now) 32 bit values needs an added cast to avoid
truncation of the result and has been added.

In order to avoid another multiplication from 32 bit domain to 64 bit
domain, the new correction_factor calculation has been changed from
new = old * (DECAY-1) / DECAY
to
new = old - old / DECAY,
which with infinite precision would yeild exactly the same result, but
now changes the direction of rounding. The impact is not significant as
the maximum accumulated difference cannot exceed the value of DECAY,
which is relatively small compared to product of RESOLUTION and DECAY
(8 / 8192).

Signed-off-by: Tuukka Tikkanen <tuukka.tikkanen@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-23 00:24:16 +02:00
Tuukka Tikkanen
decd51bbcd cpuidle: Add a comment warning about possible overflow
The menu governor has a number of tunable constants that may be changed
in the source. If certain combination of values are chosen, an overflow
is possible when the correction_factor is being recalculated.

This patch adds a warning regarding this possibility and describes the
change needed for fixing the issue. The change should not be permanently
enabled, as it will hurt performance when it is not needed.

Signed-off-by: Tuukka Tikkanen <tuukka.tikkanen@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-23 00:24:16 +02:00
Tuukka Tikkanen
0e96d5adcf cpuidle: Fix variable domains in get_typical_interval()
The menu governor uses a static function get_typical_interval() to
try to detect a repeating pattern of wakeups. The previous interval
durations are stored as an array of unsigned ints, but the arithmetic
in the function is performed exclusively as 64 bit values, even when
the value stored in a variable is known not to exceed unsigned int,
which may be smaller and more efficient on some platforms.

This patch changes the types of varibles used to store some
intermediates, the maximum and and the cutoff threshold to unsigned
ints. Average and standard deviation are still treated as 64 bit values,
even when the values are known to be within the domain of unsigned int,
to avoid casts to ensure correct integer promotion for arithmetic
operations.

Signed-off-by: Tuukka Tikkanen <tuukka.tikkanen@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-23 00:24:16 +02:00
Tuukka Tikkanen
939e33b7fc cpuidle: Fix menu_device->intervals type
Struct menu_device member intervals is declared as u32, but the value
stored is (unsigned) int. The type is changed to match the value being
stored.

Signed-off-by: Tuukka Tikkanen <tuukka.tikkanen@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-23 00:24:16 +02:00
Tuukka Tikkanen
4cd46bca8c cpuidle: CodingStyle: Break up multiple assignments on single line
The function get_typical_interval() initializes a number of variables
that are immediately after declarations assigned constant values.
In addition, there are multiple assignments on a single line, which
is explicitly forbidden by Documentation/CodingStyle.

This patch removes redundant initial values for the variables and
breaks up the multiple assignment line.

Signed-off-by: Tuukka Tikkanen <tuukka.tikkanen@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-23 00:24:16 +02:00
Tuukka Tikkanen
0d6a7ffa4c cpuidle: Check called function parameter in get_typical_interval()
get_typical_interval() uses int_sqrt() in calculation of standard
deviation. The formal parameter of int_sqrt() is unsigned long, which
may on some platforms be smaller than the 64 bit unsigned integer used
as the actual parameter. The overflow can occur frequently when actual
idle period lengths are in hundreds of milliseconds.

This patch adds a check for such overflow and rejects the candidate
average when an overflow would occur.

Signed-off-by: Tuukka Tikkanen <tuukka.tikkanen@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-23 00:24:16 +02:00
Tuukka Tikkanen
017099e25f cpuidle: Rearrange code and comments in get_typical_interval()
This patch rearranges a if-return-elsif-goto-fi-return sequence into
if-return-fi-if-return-fi-goto sequence. The functionality remains the
same. Also, a lengthy comment that did not describe the functionality
in the order it occurs is split into half and top half is moved closer
to actual implementation it describes.

Signed-off-by: Tuukka Tikkanen <tuukka.tikkanen@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-23 00:24:15 +02:00
Tuukka Tikkanen
330647a950 cpuidle: Ignore interval prediction result when timer is shorter
This patch prevents cpuidle menu governor from using repeating interval
prediction result if the idle period predicted is longer than the one
allowed by shortest running timer.

Signed-off-by: Tuukka Tikkanen <tuukka.tikkanen@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-23 00:24:15 +02:00
Julia Lawall
81455e7221 cpuidle-kirkwood.c: simplify use of devm_ioremap_resource()
Remove unneeded error handling on the result of a call to
platform_get_resource when the value is passed to
devm_ioremap_resource().

A simplified version of the semantic patch that makes this change is
as follows: (http://coccinelle.lip6.fr/)

// <smpl>
@@
expression pdev,res,n,e,e1;
expression ret != 0;
identifier l;
@@

- res = platform_get_resource(pdev, IORESOURCE_MEM, n);
  ... when != res
- if (res == NULL) { ... \(goto l;\|return ret;\) }
  ... when != res
+ res = platform_get_resource(pdev, IORESOURCE_MEM, n);
  e = devm_ioremap_resource(e1, res);
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-14 22:20:06 +02:00
Rafael J. Wysocki
f1618a7a27 Merge branch 'cpuidle/arm-next' of git://git.linaro.org/people/dlezcano/linux into pm-cpuidle
Pull ARM cpuidle updates from Daniel Lezcano.

* 'cpuidle/arm-next' of git://git.linaro.org/people/dlezcano/linux:
  cpuidle: kirkwood: Make kirkwood_cpuidle_remove function static
  cpuidle: calxeda: Add missing __iomem annotation
  SH: cpuidle: Add missing parameter for cpuidle_register()
2013-08-14 22:18:43 +02:00
Rafael J. Wysocki
ee42f75dba Merge back earlier 'pm-cpuidle' material. 2013-08-14 22:18:04 +02:00
Jingoo Han
75d6137da1 cpuidle: kirkwood: Make kirkwood_cpuidle_remove function static
This local symbol is used only in this file.
Fix the following sparse warnings:

drivers/cpuidle/cpuidle-kirkwood.c:73:5: warning: symbol 'kirkwood_cpuidle_remove' was not declared. Should it be static ?

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Jason Cooper <jason@lakedaemon.net>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2013-08-12 11:28:50 +02:00
Jingoo Han
3e0c190dbf cpuidle: calxeda: Add missing __iomem annotation
Added missing __iomem annotation in order to fix the following
sparse warnings:

drivers/cpuidle/cpuidle-calxeda.c:44:24: warning: incorrect type in argument 1 (different address spaces)
drivers/cpuidle/cpuidle-calxeda.c:44:24:    expected void [noderef] <asn:2>*<noident>
drivers/cpuidle/cpuidle-calxeda.c:44:24:    got void *extern [addressable] [toplevel] scu_base_addr
drivers/cpuidle/cpuidle-calxeda.c:56:24: warning: incorrect type in argument 1 (different address spaces)
drivers/cpuidle/cpuidle-calxeda.c:56:24:    expected void [noderef] <asn:2>*<noident>
drivers/cpuidle/cpuidle-calxeda.c:56:24:    got void *extern [addressable] [toplevel] scu_base_addr

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2013-08-12 11:28:29 +02:00