Commit Graph

418 Commits

Author SHA1 Message Date
Srinivas Pandruvada
69030dd1c3 cpufreq: use last policy after online for drivers with ->setpolicy
For cpufreq drivers which use setpolicy interface, after offline->online
the policy is set to default. This can be reproduced by setting the
default policy of intel_pstate or longrun to ondemand and then change to
"performance". After offline and online, the setpolicy will be called with
the policy=ondemand.

For drivers using governors this condition is handled by storing
last_governor, during offline and restoring during online. The same should
be done for drivers using setpolicy interface. Storing last_policy during
offline and restoring during online.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-12-02 23:50:33 +01:00
Viresh Kumar
f344dae0fe cpufreq: Always remove sysfs cpuX/cpufreq link on ->remove_dev()
Subsys interface's ->remove_dev() is called when the cpufreq driver is
unregistering or the CPU is getting physically removed. We keep removing
the cpuX/cpufreq link for all CPUs except the last one, which is a
mistake as all CPUs contain a link now.

Because of this, one CPU from each policy will still contain a link (to
an already removed policyX directory), after the cpufreq driver is
unregistered.

Fix that by removing the link first and then only see if the policy is
required to be freed. That will make sure that no links are left out.

Fixes: 96bdda61f5 ("cpufreq: create cpu/cpufreq/policyX directories")
Reported-and-tested-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-11-23 22:49:42 +01:00
Viresh Kumar
3510fac454 cpufreq: postfix policy directory with the first CPU in related_cpus
The sysfs policy directory is postfixed currently with the CPU number
for which the policy was created, which isn't necessarily the first CPU
in related_cpus mask.

To make it more consistent and predictable, lets postfix the policy with
the first cpu in related-cpus mask.

Suggested-by: Saravana Kannan <skannan@codeaurora.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Saravana Kannan <skannan@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-10-28 09:21:12 +01:00
Viresh Kumar
96bdda61f5 cpufreq: create cpu/cpufreq/policyX directories
The cpufreq sysfs interface had been a bit inconsistent as one of the
CPUs for a policy had a real directory within its sysfs 'cpuX' directory
and all other CPUs had links to it. That also made the code a bit
complex as we need to take care of moving the sysfs directory if the CPU
containing the real directory is getting physically hot-unplugged.

Solve this by creating 'policyX' directories (per-policy) in
/sys/devices/system/cpu/cpufreq/ directory, where X is the CPU for which
the policy was first created.

This also removes the need of keeping kobj_cpu and we can remove it now.

Suggested-by: Saravana Kannan <skannan@codeaurora.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Saravana Kannan <skannan@codeaurora.org>
Acked-by: is more of a general agreement from the person that he is
Reviewed-by: is a more strict tag and implies that the reviewer has
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-10-28 09:21:12 +01:00
Viresh Kumar
c82bd44437 cpufreq: remove cpufreq_sysfs_{create|remove}_file()
They don't do anything special now, remove the unnecessary wrapper.

Reviewed-by: Saravana Kannan <skannan@codeaurora.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-10-28 09:21:12 +01:00
Viresh Kumar
8eec1020f0 cpufreq: create cpu/cpufreq at boot time
Later patches will need to create policy specific directories in
/sys/devices/system/cpu/cpufreq/ directory and so the cpufreq directory
wouldn't be ever empty.

And so no fun creating/destroying it on need basis anymore. Create it
once on system boot.

Reviewed-by: Saravana Kannan <skannan@codeaurora.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-10-28 09:21:12 +01:00
Viresh Kumar
0998a03a3a cpufreq: Use cpumask_copy instead of cpumask_or to copy a mask
->related_cpus is empty at this point of time and copying ->cpus to it
or orring ->related_cpus with ->cpus would result in the same value. But
cpumask_copy makes it rather clear.

Reviewed-by: Saravana Kannan <skannan@codeaurora.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-10-28 09:21:11 +01:00
Viresh Kumar
e625742f9c cpufreq: Drop redundant check for inactive policies
We just made sure policy->cpu is online and this check will always fail
as the policy is active. Drop it.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Saravana Kannan <skannan@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-10-14 02:30:28 +02:00
Srinivas Pandruvada
55582bccdc cpufreq: prevent lockup on reading scaling_available_frequencies
When scaling_available_frequencies is read on an offlined cpu, then
either lockup or junk values are displayed. This is caused by
freed freq_table, which policy is using.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-10-08 21:47:56 +02:00
Rafael J. Wysocki
1f0bd44e93 cpufreq: acpi-cpufreq: Use cpufreq_cpu_get_raw() in ->get()
cpufreq_cpu_get() called by get_cur_freq_on_cpu() is overkill,
because the ->get() callback is always invoked in a context in
which all of the conditions checked by cpufreq_cpu_get() are
guaranteed to be satisfied.

Use cpufreq_cpu_get_raw() instead of it and drop the
corresponding cpufreq_cpu_put() from get_cur_freq_on_cpu().

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2015-09-16 02:17:49 +02:00
Rafael J. Wysocki
3e66c4b860 Merge branch 'pm-cpufreq'
* pm-cpufreq:
  intel_pstate: fix PCT_TO_HWP macro
  intel_pstate: Fix user input of min/max to legal policy region
  cpufreq-dt: add suspend frequency support
  cpufreq: allow cpufreq_generic_suspend() to work without suspend frequency
  cpufreq: Use __func__ to print function's name
  cpufreq: staticize cpufreq_cpu_get_raw()
  cpufreq: Add ARM_MT8173_CPUFREQ dependency on THERMAL
  cpufreq: dt: Tolerance applies on both sides of target voltage
  cpufreq: dt: Print error on failing to mark OPPs as shared
  cpufreq: dt: Check OPP count before marking them shared
2015-09-11 15:37:25 +02:00
Bartlomiej Zolnierkiewicz
201f371657 cpufreq: allow cpufreq_generic_suspend() to work without suspend frequency
Some cpufreq drivers may set suspend frequency only for
selected setups but still would like to use the generic
suspend handler.  Thus don't treat !policy->suspend_freq
condition as an incorrect one.

Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-09-09 02:22:55 +02:00
Viresh Kumar
63431f789c cpufreq: Use __func__ to print function's name
Its better to use __func__ to print functions name instead of writing
the name in the print statement. This also has the advantage that a
change in function's name doesn't force us to change the print message
as well.

Reviewed-by: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-09-07 23:52:28 +02:00
Viresh Kumar
d075a88e51 cpufreq: staticize cpufreq_cpu_get_raw()
cpufreq_cpu_get_raw() isn't used by any external users, staticize it.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-09-07 21:47:42 +02:00
Rafael J. Wysocki
0ed537b5fd Merge branch 'pm-opp' into pm-cpufreq 2015-09-03 02:46:01 +02:00
Linus Torvalds
ae98207309 Power management and ACPI material for v4.3-rc1
- ACPICA update to upstream revision 20150818 including method
    tracing extensions to allow more in-depth AML debugging in the
    kernel and a number of assorted fixes and cleanups (Bob Moore,
    Lv Zheng, Markus Elfring).
 
  - ACPI sysfs code updates and a documentation update related to
    AML method tracing (Lv Zheng).
 
  - ACPI EC driver fix related to serialized evaluations of _Qxx
    methods and ACPI tools updates allowing the EC userspace tool
    to be built from the kernel source (Lv Zheng).
 
  - ACPI processor driver updates preparing it for future
    introduction of CPPC support and ACPI PCC mailbox driver
    updates (Ashwin Chaugule).
 
  - ACPI interrupts enumeration fix for a regression related
    to the handling of IRQ attribute conflicts between MADT
    and the ACPI namespace (Jiang Liu).
 
  - Fixes related to ACPI device PM (Mika Westerberg, Srinidhi Kasagar).
 
  - ACPI device registration code reorganization to separate the
    sysfs-related code and bus type operations from the rest (Rafael
    J Wysocki).
 
  - Assorted cleanups in the ACPI core (Jarkko Nikula, Mathias Krause,
    Andy Shevchenko, Rafael J Wysocki, Nicolas Iooss).
 
  - ACPI cpufreq driver and ia64 cpufreq driver fixes and cleanups
    (Pan Xinhui, Rafael J Wysocki).
 
  - cpufreq core cleanups on top of the previous changes allowing it
    to preseve its sysfs directories over system suspend/resume (Viresh
    Kumar, Rafael J Wysocki, Sebastian Andrzej Siewior).
 
  - cpufreq fixes and cleanups related to governors (Viresh Kumar).
 
  - cpufreq updates (core and the cpufreq-dt driver) related to the
    turbo/boost mode support (Viresh Kumar, Bartlomiej Zolnierkiewicz).
 
  - New DT bindings for Operating Performance Points (OPP), support
    for them in the OPP framework and in the cpufreq-dt driver plus
    related OPP framework fixes and cleanups (Viresh Kumar).
 
  - cpufreq powernv driver updates (Shilpasri G Bhat).
 
  - New cpufreq driver for Mediatek MT8173 (Pi-Cheng Chen).
 
  - Assorted cpufreq driver (speedstep-lib, sfi, integrator) cleanups
    and fixes (Abhilash Jindal, Andrzej Hajda, Cristian Ardelean).
 
  - intel_pstate driver updates including Skylake-S support, support
    for enabling HW P-states per CPU and an additional vendor bypass
    list entry (Kristen Carlson Accardi, Chen Yu, Ethan Zhao).
 
  - cpuidle core fixes related to the handling of coupled idle states
    (Xunlei Pang).
 
  - intel_idle driver updates including Skylake Client support and
    support for freeze-mode-specific idle states (Len Brown).
 
  - Driver core updates related to power management (Andy Shevchenko,
    Rafael J Wysocki).
 
  - Generic power domains framework fixes and cleanups (Jon Hunter,
    Geert Uytterhoeven, Rajendra Nayak, Ulf Hansson).
 
  - Device PM QoS framework update to allow the latency tolerance
    setting to be exposed to user space via sysfs (Mika Westerberg).
 
  - devfreq support for PPMUv2 in Exynos5433 and a fix for an incorrect
    exynos-ppmu DT binding (Chanwoo Choi, Javier Martinez Canillas).
 
  - System sleep support updates (Alan Stern, Len Brown, SungEun Kim).
 
  - rockchip-io AVS support updates (Heiko Stuebner).
 
  - PM core clocks support fixup (Colin Ian King).
 
  - Power capping RAPL driver update including support for Skylake H/S
    and Broadwell-H (Radivoje Jovanovic, Seiichi Ikarashi).
 
  - Generic device properties framework fixes related to the handling
    of static (driver-provided) property sets (Andy Shevchenko).
 
  - turbostat and cpupower updates (Len Brown, Shilpasri G Bhat,
    Shreyas B Prabhu).
 
 /
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Merge tag 'pm+acpi-4.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management and ACPI updates from Rafael Wysocki:
 "From the number of commits perspective, the biggest items are ACPICA
  and cpufreq changes with the latter taking the lead (over 50 commits).

  On the cpufreq front, there are many cleanups and minor fixes in the
  core and governors, driver updates etc.  We also have a new cpufreq
  driver for Mediatek MT8173 chips.

  ACPICA mostly updates its debug infrastructure and adds a number of
  fixes and cleanups for a good measure.

  The Operating Performance Points (OPP) framework is updated with new
  DT bindings and support for them among other things.

  We have a few updates of the generic power domains framework and a
  reorganization of the ACPI device enumeration code and bus type
  operations.

  And a lot of fixes and cleanups all over.

  Included is one branch from the MFD tree as it contains some
  PM-related driver core and ACPI PM changes a few other commits are
  based on.

  Specifics:

   - ACPICA update to upstream revision 20150818 including method
     tracing extensions to allow more in-depth AML debugging in the
     kernel and a number of assorted fixes and cleanups (Bob Moore, Lv
     Zheng, Markus Elfring).

   - ACPI sysfs code updates and a documentation update related to AML
     method tracing (Lv Zheng).

   - ACPI EC driver fix related to serialized evaluations of _Qxx
     methods and ACPI tools updates allowing the EC userspace tool to be
     built from the kernel source (Lv Zheng).

   - ACPI processor driver updates preparing it for future introduction
     of CPPC support and ACPI PCC mailbox driver updates (Ashwin
     Chaugule).

   - ACPI interrupts enumeration fix for a regression related to the
     handling of IRQ attribute conflicts between MADT and the ACPI
     namespace (Jiang Liu).

   - Fixes related to ACPI device PM (Mika Westerberg, Srinidhi
     Kasagar).

   - ACPI device registration code reorganization to separate the
     sysfs-related code and bus type operations from the rest (Rafael J
     Wysocki).

   - Assorted cleanups in the ACPI core (Jarkko Nikula, Mathias Krause,
     Andy Shevchenko, Rafael J Wysocki, Nicolas Iooss).

   - ACPI cpufreq driver and ia64 cpufreq driver fixes and cleanups (Pan
     Xinhui, Rafael J Wysocki).

   - cpufreq core cleanups on top of the previous changes allowing it to
     preseve its sysfs directories over system suspend/resume (Viresh
     Kumar, Rafael J Wysocki, Sebastian Andrzej Siewior).

   - cpufreq fixes and cleanups related to governors (Viresh Kumar).

   - cpufreq updates (core and the cpufreq-dt driver) related to the
     turbo/boost mode support (Viresh Kumar, Bartlomiej Zolnierkiewicz).

   - New DT bindings for Operating Performance Points (OPP), support for
     them in the OPP framework and in the cpufreq-dt driver plus related
     OPP framework fixes and cleanups (Viresh Kumar).

   - cpufreq powernv driver updates (Shilpasri G Bhat).

   - New cpufreq driver for Mediatek MT8173 (Pi-Cheng Chen).

   - Assorted cpufreq driver (speedstep-lib, sfi, integrator) cleanups
     and fixes (Abhilash Jindal, Andrzej Hajda, Cristian Ardelean).

   - intel_pstate driver updates including Skylake-S support, support
     for enabling HW P-states per CPU and an additional vendor bypass
     list entry (Kristen Carlson Accardi, Chen Yu, Ethan Zhao).

   - cpuidle core fixes related to the handling of coupled idle states
     (Xunlei Pang).

   - intel_idle driver updates including Skylake Client support and
     support for freeze-mode-specific idle states (Len Brown).

   - Driver core updates related to power management (Andy Shevchenko,
     Rafael J Wysocki).

   - Generic power domains framework fixes and cleanups (Jon Hunter,
     Geert Uytterhoeven, Rajendra Nayak, Ulf Hansson).

   - Device PM QoS framework update to allow the latency tolerance
     setting to be exposed to user space via sysfs (Mika Westerberg).

   - devfreq support for PPMUv2 in Exynos5433 and a fix for an incorrect
     exynos-ppmu DT binding (Chanwoo Choi, Javier Martinez Canillas).

   - System sleep support updates (Alan Stern, Len Brown, SungEun Kim).

   - rockchip-io AVS support updates (Heiko Stuebner).

   - PM core clocks support fixup (Colin Ian King).

   - Power capping RAPL driver update including support for Skylake H/S
     and Broadwell-H (Radivoje Jovanovic, Seiichi Ikarashi).

   - Generic device properties framework fixes related to the handling
     of static (driver-provided) property sets (Andy Shevchenko).

   - turbostat and cpupower updates (Len Brown, Shilpasri G Bhat,
     Shreyas B Prabhu)"

* tag 'pm+acpi-4.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (180 commits)
  cpufreq: speedstep-lib: Use monotonic clock
  cpufreq: powernv: Increase the verbosity of OCC console messages
  cpufreq: sfi: use kmemdup rather than duplicating its implementation
  cpufreq: drop !cpufreq_driver check from cpufreq_parse_governor()
  cpufreq: rename cpufreq_real_policy as cpufreq_user_policy
  cpufreq: remove redundant 'policy' field from user_policy
  cpufreq: remove redundant 'governor' field from user_policy
  cpufreq: update user_policy.* on success
  cpufreq: use memcpy() to copy policy
  cpufreq: remove redundant CPUFREQ_INCOMPATIBLE notifier event
  cpufreq: mediatek: Add MT8173 cpufreq driver
  dt-bindings: mediatek: Add MT8173 CPU DVFS clock bindings
  PM / Domains: Fix typo in description of genpd_dev_pm_detach()
  PM / Domains: Remove unusable governor dummies
  PM / Domains: Make pm_genpd_init() available to modules
  PM / domains: Align column headers and data in pm_genpd_summary output
  powercap / RAPL: disable the 2nd power limit properly
  tools: cpupower: Fix error when running cpupower monitor
  PM / OPP: Drop unlikely before IS_ERR(_OR_NULL)
  PM / OPP: Fix static checker warning (broken 64bit big endian systems)
  ...
2015-09-01 19:45:46 -07:00
Rafael J. Wysocki
ac2a29c8a4 Merge branch 'pm-opp'
* pm-opp:
  PM / OPP: Drop unlikely before IS_ERR(_OR_NULL)
  PM / OPP: Fix static checker warning (broken 64bit big endian systems)
  PM / OPP: Free resources and properly return error on failure
  cpufreq-dt: make scaling_boost_freqs sysfs attr available when boost is enabled
  cpufreq: dt: Add support for turbo/boost mode
  cpufreq: dt: Add support for operating-points-v2 bindings
  cpufreq: Allow drivers to enable boost support after registering driver
  cpufreq: Update boost flag while initializing freq table from OPPs
  PM / OPP: add dev_pm_opp_is_turbo() helper
  PM / OPP: Add helpers for initializing CPU OPPs
  PM / OPP: Add support for opp-suspend
  PM / OPP: Add OPP sharing information to OPP library
  PM / OPP: Add clock-latency-ns support
  PM / OPP: Add support to parse "operating-points-v2" bindings
  PM / OPP: Break _opp_add_dynamic() into smaller functions
  PM / OPP: Allocate dev_opp from _add_device_opp()
  PM / OPP: Create _remove_device_opp() for freeing dev_opp
  PM / OPP: Relocate few routines
  PM / OPP: Create a directory for opp bindings
  PM / OPP: Update bindings to make opp-hz a 64 bit value
2015-09-01 15:52:41 +02:00
Viresh Kumar
36dfef23cd cpufreq: drop !cpufreq_driver check from cpufreq_parse_governor()
Driver is guaranteed to be present on a call to cpufreq_parse_governor()
and there is no need to check for !cpufreq_driver. Drop it.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-09-01 15:50:39 +02:00
Viresh Kumar
88dc438495 cpufreq: remove redundant 'policy' field from user_policy
Its always same as policy->policy, and there is no need to keep another
copy of it. Remove it.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-09-01 15:50:39 +02:00
Viresh Kumar
e27f8bd248 cpufreq: remove redundant 'governor' field from user_policy
Its always same as policy->governor, and there is no need to keep
another copy of it. Remove it.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-09-01 15:50:39 +02:00
Viresh Kumar
14ca0bdfdd cpufreq: update user_policy.* on success
'user_policy' caches properties of a policy that are set by userspace.
And these must be updated only if cpufreq core was successful in
updating them based on request from user space.

In store_scaling_governor(), we are updating user_policy.policy and
user_policy.governor even if cpufreq_set_policy() failed. That's
incorrect.

Fix this by updating user_policy.* only if we were successful in
updating the properties.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-09-01 15:50:39 +02:00
Viresh Kumar
8fa5b631f3 cpufreq: use memcpy() to copy policy
cpufreq_get_policy() is useful if the pointer to policy isn't available
in advance. But if it is available, then there is no need to call
cpufreq_get_policy(). Directly use memcpy() to copy the policy.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-09-01 15:50:38 +02:00
Viresh Kumar
6bfb7c7434 cpufreq: remove redundant CPUFREQ_INCOMPATIBLE notifier event
What's being done from CPUFREQ_INCOMPATIBLE, can also be done with
CPUFREQ_ADJUST. There is nothing special with CPUFREQ_INCOMPATIBLE
notifier.

Kill CPUFREQ_INCOMPATIBLE and fix its usage sites.

This also updates the numbering of notifier events to remove holes.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-09-01 15:50:38 +02:00
Linus Torvalds
1af115d675 Driver core patches for 4.3-rc1
Here is the new patches for the driver core / sysfs for 4.3-rc1.
 
 Very small number of changes here, all the details are in the shortlog,
 nothing major happening at all this kernel release, which is nice to
 see.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-4.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core updates from Greg KH:
 "Here is the new patches for the driver core / sysfs for 4.3-rc1.

  Very small number of changes here, all the details are in the
  shortlog, nothing major happening at all this kernel release, which is
  nice to see"

* tag 'driver-core-4.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  bus: subsys: update return type of ->remove_dev() to void
  driver core: correct device's shutdown order
  driver core: fix docbook for device_private.device
  selftests: firmware: skip timeout checks for kernels without user mode helper
  kernel, cpu: Remove bogus __ref annotations
  cpu: Remove bogus __ref annotation of cpu_subsys_online()
  firmware: fix wrong memory deallocation in fw_add_devm_name()
  sysfs.txt: update show method notes about sprintf/snprintf/scnprintf usage
  devres: fix devres_get()
2015-08-31 08:47:40 -07:00
Viresh Kumar
44139ed494 cpufreq: Allow drivers to enable boost support after registering driver
In some cases it wouldn't be known at time of driver registration, if
the driver needs to support boost frequencies.

For example, while getting boost information from DT with opp-v2
bindings, we need to parse the bindings for all the CPUs to know if
turbo/boost OPPs are supported or not.

One way out to do that efficiently is to delay supporting boost mode
(i.e. creating /sys/devices/system/cpu/cpufreq/boost file), until the
time OPP bindings are parsed.

At that point, the driver can enable boost support. This can be done at
->init(), where the frequency table is created.

To do that, the driver requires few APIs from cpufreq core that let him
do this. This patch provides these APIs.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-08-07 03:25:23 +02:00
Viresh Kumar
71db87ba57 bus: subsys: update return type of ->remove_dev() to void
Its return value is not used by the subsys core and nothing meaningful
can be done with it, even if we want to use it. The subsys device is
anyway getting removed.

Update prototype of ->remove_dev() to make its return type as void. Fix
all usage sites as well.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-08-05 17:08:14 -07:00
Pan Xinhui
fba9573b33 cpufreq: Correct a freq check in cpufreq_set_policy()
This check was originally added by commit 9c9a43ed27 ("[CPUFREQ]
return error when failing to set minfreq").It attempt to return an error
on obviously incorrect limits when we echo xxx >.../scaling_max,min_freq
Actually we just need check if new_policy->min > new_policy->max.
Because at least one of max/min is copied from cpufreq_get_policy().

For example, when we echo xxx > .../scaling_min_freq, new_policy is
copied from policy in cpufreq_get_policy. new_policy->max is same with
policy->max. new_policy->min is set to a new value.

Let me explain it in deduction method, first statement in if ():
new_policy->min > policy->max
policy->max == new_policy->max
==> new_policy->min > new_policy->max

second statement in if():
new_policy->max < policy->min
policy->max < policy->min
==>new_policy->min > new_policy->max (induction method)

So we have proved that we only need check if new_policy->min >
new_policy->max.

After apply this patch, we can also modify ->min and ->max at same time
if new freq range is very much different from current freq range. For
example, if current freq range is 480000-960000, then we want to set
this range to 1120000-2240000, we would fail in the past because
new_policy->min > policy->max. As long as the cpufreq range is valid, we
has no reason to reject the user. So correct the check to avoid such
case.

Signed-off-by: Pan Xinhui <xinhuix.pan@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-07-31 23:22:16 +02:00
Rafael J. Wysocki
fdd320da84 cpufreq: Lock CPU online/offline in cpufreq_register_driver()
To protect against races with concurrent CPU online/offline, call
get_online_cpus() before registering a cpufreq driver.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2015-07-31 22:01:19 +02:00
Rafael J. Wysocki
194d99c7e3 cpufreq: Replace recover_policy with new_policy in cpufreq_online()
The recover_policy is unsed in cpufreq_online() to indicate whether
a new policy object is created or an existing one is reinitialized.

The "recover" part of the name is slightly confusing (it should be
"reinitialization" rather than "recovery") and the logical not (!)
operator is applied to it in almost all of the checks it is used in,
so replace that variable with a new one called "new_policy" that
will be true in the case of a new policy creation.

While at it, drop one of the labels that is jumped to from only
one spot.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2015-07-31 22:00:31 +02:00
Rafael J. Wysocki
0b27535287 cpufreq: Separate CPU device registration from CPU online
To separate the CPU online interface from the CPU device
registration, split cpufreq_online() out of cpufreq_add_dev()
and make cpufreq_cpu_callback() call the former, while
cpufreq_add_dev() itself will only be used as the CPU device
addition subsystem interface callback.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Suggested-by: Russell King <linux@arm.linux.org.uk>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2015-07-31 21:59:37 +02:00
Rafael J. Wysocki
a34e63b144 cpufreq: Pass CPU number to cpufreq_policy_alloc()
Change cpufreq_policy_alloc() to take a CPU number instead of a CPU
device pointer as its argument, as it is the only function called by
cpufreq_add_dev() taking a device pointer argument at this point.

That will allow us to split the CPU online part from cpufreq_add_dev()
more cleanly going forward.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2015-07-28 17:24:12 +02:00
Rafael J. Wysocki
4d1f3a5bcb cpufreq: Do not update related_cpus on every policy activation
The related_cpus mask includes CPUs whose cpufreq_cpu_data per-CPU
pointers have been set the the given policy.  Since those pointers
are only set at the policy creation time and unset when the policy
is deleted, the related_cpus should not be updated between those
two operations.

For this reason, avoid updating it whenever the first of the
"related" CPUs goes online.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2015-07-28 17:24:12 +02:00
Rafael J. Wysocki
d9612a495b cpufreq: Drop unused dev argument from two functions
The dev argument of cpufreq_add_policy_cpu() and
cpufreq_add_dev_interface() is not used by any of them,
so drop it.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2015-07-28 17:24:11 +02:00
Rafael J. Wysocki
d4d854d6c7 cpufreq: Drop unnecessary label from cpufreq_add_dev()
The leftover out_release_rwsem label in cpufreq_add_dev() is not
necessary any more and confusing, so drop it.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2015-07-28 17:24:11 +02:00
Rafael J. Wysocki
11ce707e6c cpufreq: Drop cpufreq_policy_restore()
Notice that when cpufreq_policy_restore() is called, its per-CPU
cpufreq_cpu_data variable has been already dereferenced and if that
variable is not NULL, the policy local pointer in cpufreq_add_dev()
contains its value.

Therefore it is not necessary to dereference it again and the
policy pointer can be used directly.  Moreover, if that pointer
is not NULL, the policy is inactive (or the previous check would
have made us return from cpufreq_add_dev()) so the restoration
code from cpufreq_policy_restore() can be moved to that point
in cpufreq_add_dev().

Do that and drop cpufreq_policy_restore().

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2015-07-28 17:24:10 +02:00
Rafael J. Wysocki
15c0b4d222 cpufreq: Rework two functions related to CPU offline
Since __cpufreq_remove_dev_prepare() and __cpufreq_remove_dev_finish()
are about CPU offline rather than about CPU removal, rename them to
cpufreq_offline_prepare() and cpufreq_offline_finish(), respectively.

Also change their argument from a struct device pointer to a CPU
number, because they use the CPU number only internally anyway
and make them void as their return values are ignored.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2015-07-28 17:24:10 +02:00
Rafael J. Wysocki
c6e53c69ef Merge back earlier cpufreq material for v4.3. 2015-07-28 17:21:32 +02:00
Rafael J. Wysocki
559ed40752 cpufreq: Avoid attempts to create duplicate symbolic links
After commit 87549141d5 (cpufreq: Stop migrating sysfs files on
hotplug) there is a problem with CPUs that share cpufreq policy
objects with other CPUs and are initially offline.

Say CPU1 shares a policy with CPU0 which is online and is registered
first.  As part of the registration process, cpufreq_add_dev() is
called for it.  It creates the policy object and a symbolic link
to it from the CPU1's sysfs directory.  If CPU1 is registered
subsequently and it is offline at that time, cpufreq_add_dev() will
attempt to create a symbolic link to the policy object for it, but
that link is present already, so a warning about that will be
triggered.

To avoid that warning, make cpufreq use an additional CPU mask
containing related CPUs that are actually present for each policy
object.  That mask is initialized when the policy object is populated
after its creation (for the first online CPU using it) and it includes
CPUs from the "policy CPUs" mask returned by the cpufreq driver's
->init() callback that are physically present at that time.  Symbolic
links to the policy are created only for the CPUs in that mask.

If cpufreq_add_dev() is invoked for an offline CPU, it checks the
new mask and only creates the symlink if the CPU was not in it (the
CPU is added to the mask at the same time).

In turn, cpufreq_remove_dev() drops the given CPU from the new mask,
removes its symlink to the policy object and returns, unless it is
the CPU owning the policy object.  In that case, the policy object
is moved to a new CPU's sysfs directory or deleted if the CPU being
removed was the last user of the policy.

While at it, notice that cpufreq_remove_dev() can't fail, because
its return value is ignored, so make it ignore return values from
__cpufreq_remove_dev_prepare() and __cpufreq_remove_dev_finish()
and prevent these functions from aborting on errors returned by
__cpufreq_governor().  Also drop the now unused sif argument from
them.

Fixes: 87549141d5 (cpufreq: Stop migrating sysfs files on hotplug)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reported-and-tested-by: Russell King <linux@arm.linux.org.uk>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2015-07-28 17:19:26 +02:00
Sebastian Andrzej Siewior
454d3a2500 cpufreq: Remove cpufreq_rwsem
cpufreq_rwsem was introduced in commit 6eed9404ab ("cpufreq: Use
rwsem for protecting critical sections) in order to replace
try_module_get() on the cpu-freq driver. That try_module_get() worked
well until the refcount was so heavily used that module removal became
more or less impossible.

Though when looking at the various (undocumented) protection
mechanisms in that code, the randomly sprinkeled around cpufreq_rwsem
locking sites are superfluous.

The policy, which is acquired in cpufreq_cpu_get() and released in
cpufreq_cpu_put() is sufficiently protected already.

  cpufreq_cpu_get(cpu)
    /* Protects against concurrent driver removal */
    read_lock_irqsave(&cpufreq_driver_lock, flags);
    policy = per_cpu(cpufreq_cpu_data, cpu);
    kobject_get(&policy->kobj);
    read_unlock_irqrestore(&cpufreq_driver_lock, flags);

The reference on the policy serializes versus module unload already:

  cpufreq_unregister_driver()
    subsys_interface_unregister()
      __cpufreq_remove_dev_finish()
        per_cpu(cpufreq_cpu_data) = NULL;
	cpufreq_policy_put_kobj()

If there is a reference held on the policy, i.e. obtained prior to the
unregister call, then cpufreq_policy_put_kobj() will wait until that
reference is dropped. So once subsys_interface_unregister() returns
there is no policy pointer in flight and no new reference can be
obtained. So that rwsem protection is useless.

The other usage of cpufreq_rwsem in show()/store() of the sysfs
interface is redundant as well because sysfs already does the proper
kobject_get()/put() pairs.

That leaves CPU hotplug versus module removal. The current
down_write() around the write_lock() in cpufreq_unregister_driver() is
silly at best as it protects actually nothing.

The trivial solution to this is to prevent hotplug across
cpufreq_unregister_driver completely.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-07-25 01:49:01 +02:00
Viresh Kumar
4bc384ae62 cpufreq: propagate errors returned from __cpufreq_governor()
Return codes aren't honored properly in cpufreq_set_policy(). This can
lead to two problems:
- wrong errors propagated to sysfs
- we try to do next state-change even if the previous one failed

cpufreq_governor_dbs() now returns proper errors on all invalid
state-transition requests and this code should honor that.

Reviewed-and-tested-by: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-07-21 01:12:02 +02:00
Viresh Kumar
7f0fa40f5a cpufreq: Properly handle errors from cpufreq_init_policy()
cpufreq_init_policy() can fail, and we don't do anything except a call
to ->exit() on that. The policy should be freed if this happens.

Do it properly.

Reported-and-tested-by: "Jon Medhurst (Tixy)" <tixy@linaro.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-07-16 23:51:26 +02:00
Viresh Kumar
8101f99703 cpufreq: cpufreq_add_dev: name goto labels based on what they do
These labels are are named in two ways normally:
 - Based on what caused to jump to such labels
 - Based on what we do under such labels

We follow the first naming convention today and that leads to multiple
labels for doing the same work. Fix it by switching to the second way of
naming them.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-07-16 23:51:25 +02:00
Viresh Kumar
5a31d594a9 cpufreq: Allow freq_table to be obtained for offline CPUs
Users of freq table may want to access it for any CPU from
policy->related_cpus mask. One such user is cpu-cooling layer. It gets a
list of 'clip_cpus' (equivalent to policy->related_cpus) during
registration and tries to get freq_table for the first CPU of this mask.

If the CPU, for which it tries to fetch freq_table, is offline,
cpufreq_frequency_get_table() fails. This happens because it relies on
cpufreq_cpu_get_raw() for its functioning which returns policy only for
online CPUs.

The fix is to access the policy data structure for the given CPU
directly (which also returns a valid policy for offline CPUs), but the
policy itself has to be active (meaning that at least one CPU using it
is online) for the frequency table to be returned.

Because we will be using 'cpufreq_cpu_data' now, which is internal to
the cpufreq core, move cpufreq_frequency_get_table() to cpufreq.c.

Reported-and-tested-by: Pi-Cheng Chen <pi-cheng.chen@linaro.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-07-10 01:43:27 +02:00
Viresh Kumar
35afd02e30 cpufreq: Initialize the governor again while restoring policy
When all CPUs of a policy are hot-unplugged, we EXIT the governor but
don't mark policy->governor as NULL. This was done in order to keep last
used governor's information intact in sysfs, while the CPUs are offline.

But we also need to clear policy->governor when restoring the policy.

Because policy->governor still points to the last governor while policy
is restored, following sequence of event happens:
 - cpufreq_init_policy() called while restoring policy
 - find_governor() matches last_governor string for present governors and
   returns last used governor's pointer, say ondemand. policy->governor
   already has the same address, unless the governor was removed in
   between.
 - cpufreq_set_policy() is called with both old/new policies governor set
   as ondemand.
 - Because governors matched, we skip governor initialization and return
   after calling __cpufreq_governor(CPUFREQ_GOV_LIMITS). Because the
   governor wasn't initialized for this policy, it returned -EBUSY.
 - cpufreq_init_policy() exits the policy on this error, but doesn't
   destroy it properly (should be fixed separately).
 - And so we enter a scenario where the policy isn't completely
   initialized but used.

Fix this by setting policy->governor to NULL while restoring the policy.

Reported-and-tested-by: Pi-Cheng Chen <pi-cheng.chen@linaro.org>
Reported-and-tested-by: "Jon Medhurst (Tixy)" <tixy@linaro.org>
Reported-and-tested-by: Steven Rostedt <rostedt@goodmis.org>
Fixes: 18bf3a124e (cpufreq: Mark policy->governor = NULL for inactive policies)
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-07-10 01:36:27 +02:00
Viresh Kumar
3782902983 cpufreq: Remove cpufreq_update_policy()
cpufreq_update_policy() was kept as a separate routine earlier as it was
handling migration of sysfs directories, which isn't the case anymore.
It is only updating policy->cpu now and is called by a single caller.

The WARN_ON() isn't really required anymore, as we are just updating the
cpu now, not moving the sysfs directories.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-06-11 01:03:04 +02:00
Viresh Kumar
9591becbf2 cpufreq: Restart governor as soon as possible
__cpufreq_remove_dev_finish() is doing two things today:
- Restarts the governor if some CPUs from concerned policy are still
  online.
- Frees the policy if all CPUs are offline.

The first task of restarting the governor can be moved to
__cpufreq_remove_dev_prepare() to restart the governor early. There is
no race between _prepare() and _finish() as they would be handling
completely different cases. _finish() will only be required if we are
going to free the policy and that has nothing to do with restarting the
governor.

Original-by: Saravana Kannan <skannan@codeaurora.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-06-11 01:02:45 +02:00
Viresh Kumar
3654c5cc81 cpufreq: Call cpufreq_policy_put_kobj() from cpufreq_policy_free()
cpufreq_policy_put_kobj() is actually part of freeing the policy and can
be called from cpufreq_policy_free() directly instead of a separate
call.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-06-11 01:02:40 +02:00
Viresh Kumar
2fc3384dc7 cpufreq: Initialize policy->kobj while allocating policy
policy->kobj is required to be initialized once in the lifetime of a
policy.  Currently we are initializing it from __cpufreq_add_dev() and
that doesn't look to be the best place for doing so as we have to do
this on special cases (like: !recover_policy).

We can initialize it from a more obvious place cpufreq_policy_alloc()
and that will make code look cleaner, specially the error handling part.

The error handling part of __cpufreq_add_dev() was doing almost the same
thing while recover_policy is true or false. Fix that as well by always
calling cpufreq_policy_put_kobj() with an additional parameter to skip
notification part of it.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-06-11 01:01:54 +02:00
Viresh Kumar
87549141d5 cpufreq: Stop migrating sysfs files on hotplug
When we hot-unplug a cpu, we remove its sysfs cpufreq directory and if
the outgoing cpu was the owner of policy->kobj earlier then we migrate
the sysfs directory to under another online cpu.

There are few disadvantages this brings:
- Code Complexity
- Slower hotplug/suspend/resume
- sysfs file permissions are reset after all policy->cpus are offlined
- CPUFreq stats history lost after all policy->cpus are offlined
- Special management of sysfs stuff during suspend/resume

To overcome these, this patch modifies the way sysfs directories are
managed:
- Select sysfs kobjects owner while initializing policy and don't change
  it during hotplugs. Track it with kobj_cpu created earlier.

- Create symlinks for all related CPUs (can be offline) instead of
  affected CPUs on policy initialization and remove them only when the
  policy is freed.

- Free policy structure only on the removal of cpufreq-driver and not
  during hotplug/suspend/resume, detected by checking 'struct
  subsys_interface *' (Valid only when called from
  subsys_interface_unregister() while unregistering driver).

Apart from this, special care is taken to handle physical hoplug of CPUs
as we wouldn't remove sysfs links or remove policies on logical
hotplugs. Physical hotplug happens in the following sequence.

Hot removal:
- CPU is offlined first, ~ 'echo 0 >
  /sys/devices/system/cpu/cpuX/online'
- Then its device is removed along with all sysfs files, cpufreq core
  notified with cpufreq_remove_dev() callback from subsys-interface..

Hot addition:
- First the device along with its sysfs files is added, cpufreq core
  notified with cpufreq_add_dev() callback from subsys-interface..
- CPU is onlined, ~ 'echo 1 > /sys/devices/system/cpu/cpuX/online'

We call the same routines with both hotplug and subsys callbacks, and we
sense physical hotplug with cpu_offline() check in subsys callback. We
can handle most of the stuff with regular hotplug callback paths and
add/remove cpufreq sysfs links or free policy from subsys callbacks.

Original-by: Saravana Kannan <skannan@codeaurora.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-06-11 01:00:42 +02:00
Viresh Kumar
11e584cfb8 cpufreq: Don't allow updating inactive policies from sysfs
Later commits would change the way policies are managed today. Policies
wouldn't be freed on cpu hotplug (currently they aren't freed only for
suspend), and while the CPU is offline, the sysfs cpufreq files would
still be present.

User may accidentally try to update the sysfs files in following
directory: '/sys/devices/system/cpu/cpuX/cpufreq/'. And that would
result in undefined behavior as policy wouldn't be active then.

Apart from updating the store() routine, we also update __cpufreq_get()
which can call cpufreq_out_of_sync(). The later routine tries to update
policy->cur and starts notifying kernel about it.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Saravana Kannan <skannan@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-06-10 02:11:45 +02:00