Commit Graph

18 Commits

Author SHA1 Message Date
Shunyong Yang 8913315e94 cpufreq: CPPC: Initialize shared perf capabilities of CPUs
When multiple CPUs are related in one cpufreq policy, the first online
CPU will be chosen by default to handle cpufreq operations. Let's take
cpu0 and cpu1 as an example.

When cpu0 is offline, policy->cpu will be shifted to cpu1. cpu1's perf
capabilities should be initialized. Otherwise, perf capabilities are 0s
and speed change can not take effect.

This patch copies perf capabilities of the first online CPU to other
shared CPUs when policy shared type is CPUFREQ_SHARED_TYPE_ANY.

Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Shunyong Yang <shunyong.yang@hxt-semitech.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-04-10 08:38:02 +02:00
Viresh Kumar b8b10bc201 cpufreq: CPPC: Don't set transition_latency
Now that the driver has started to set transition_delay_us directly,
there is no need to set transition_latency along with it, as it is not
used by the cpufreq core.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-04-10 08:38:02 +02:00
George Cherian 3d41386d55 cpufreq: CPPC: Use transition_delay_us depending transition_latency
With commit e948bc8fbe (cpufreq: Cap the default transition delay
value to 10 ms)  the cpufreq was not honouring the delay passed via
ACPI (PCCT). Due to which on ARM based platforms using CPPC the
cpufreq governor tries to change the frequency of CPUs faster than
expected.

This leads to continuous error messages like the following.
" ACPI CPPC: PCC check channel failed. Status=0 "

Earlier (without above commit) the default transition delay was
taken form the value passed from PCCT. Use the same value provided
by PCCT to set the transition_delay_us.

Fixes: e948bc8fbe (cpufreq: Cap the default transition delay value to 10 ms)
Signed-off-by: George Cherian <george.cherian@cavium.com>
Cc: 4.14+ <stable@vger.kernel.org> # 4.14+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-03-30 12:15:58 +02:00
Chunyu Hu 55b55abc17 cpufreq: cppc_cpufreq: Fix cppc_cpufreq_init() failure path
Kmemleak reported the below leak. When cppc_cpufreq_init went into
failure path, the cpu mask is not freed. After fix, this report is
gone. And to avaoid potential NULL pointer reference, check the cpu
value first.

unreferenced object 0xffff800fd5ea4880 (size 128):
  comm "swapper/0", pid 1, jiffies 4294939510 (age 668.680s)
  hex dump (first 32 bytes):
    00 00 00 00 20 00 00 00 00 00 00 00 00 00 00 00  .... ...........
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<ffff0000082c4ae4>] __kmalloc_node+0x278/0x634
    [<ffff0000088f4a74>] alloc_cpumask_var_node+0x28/0x60
    [<ffff0000088f4af0>] zalloc_cpumask_var+0x14/0x1c
    [<ffff000008d20254>] cppc_cpufreq_init+0xd0/0x19c
    [<ffff000008083828>] do_one_initcall+0xec/0x15c
    [<ffff000008cd1018>] kernel_init_freeable+0x1f4/0x2a4
    [<ffff0000089099b0>] kernel_init+0x18/0x10c
    [<ffff000008084d50>] ret_from_fork+0x10/0x18
    [<ffffffffffffffff>] 0xffffffffffffffff

Signed-off-by: Chunyu Hu <chuhu@redhat.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-03-20 10:52:31 +01:00
Sudeep Holla b20a3f3d8a cpufreq: remove setting of policy->cpu in policy->cpus during init
policy->cpu is copied into policy->cpus in cpufreq_online() before
calling into cpufreq_driver->init(). So there's no need to set the
same in the individual driver init() functions again.

This patch removes the redundant setting of policy->cpu in policy->cpus
in intel_pstate and cppc drivers.

Reported-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-08-18 01:41:37 +02:00
Prakash, Prashanth 73808d0fd2 cpufreq / CPPC: Initialize policy->min to lowest nonlinear performance
Description of Lowest Perfomance in ACPI 6.1 specification states:
"Lowest Performance is the absolute lowest performance level of
the platform. Selecting a performance level lower than the lowest
nonlinear performance level may actually cause an efficiency penalty,
but should reduce the instantaneous power consumption of the processor.
In traditional terms, this represents the T-state range of performance
levels."

Set the default value of policy->min to Lowest Nonlinear Performance
to avoid any potential efficiency penalty.

Signed-off-by: Prashanth Prakash <pprakash@codeaurora.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Alexey Klimov <alexey.klimov@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-06-27 02:19:39 +02:00
Prakash, Prashanth 974f86498e cpufreq / CPPC: Add MODULE_DEVICE_TABLE for cppc_cpufreq driver
MODULE_DEVICE_TABLE is added so that CPPC cpufreq module can be
automatically loaded when we have a acpi processor device with
"ACPI0007" hid.

Signed-off-by: Prashanth Prakash <pprakash@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-10-21 15:11:23 +02:00
Linus Torvalds ef98988ba3 More power management updates for v4.9-rc1
- Fix two cpufreq regressions causing undesirable changes in
    behavior to appear (one in the core and one in the conservative
    governor) introduced during the 4.8 cycle (Aaro Koskinen, Rafael
    Wysocki).
 
  - Fix the way the intel_pstate driver accesses MSRs related to the
    hardware-managed P-states (HWP) feature during the initialization
    which currently is unsafe and may cause the processor to generate
    a general protection fault (Srinivas Pandruvada).
 
  - Rework the intel_pstate's P-state selection algorithm used on Atom
    processors to avoid known problems with the current one and to
    make the computation more straightforward, which also happens to
    improve performance in multiple benchmarks a bit (Rafael Wysocki).
 
  - Improve two comments in the intel_pstate driver (Rafael Wysocki).
 
  - Fix the desired performance computation in the CPPC cpufreq driver
    (Hoan Tran).
 
  - Fix the devfreq core to avoid printing misleading error messages
    in some cases (Tobias Jakobi).
 
  - Fix the error code path in devfreq_add_device() to use proper
    locking around list modifications (Axel Lin).
 
  - Fix a build failure and remove a couple of redundant updates of
    variables in the exynos-nocp devfreq driver (Axel Lin).
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Merge tag 'pm-extra-4.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull more power management updates from Rafael Wysocki:
 "This includes a couple of fixes for cpufreq regressions introduced in
  4.8, a rework of the intel_pstate algorithm used on Atom processors
  (that took some time to test) plus a fix and a couple of cleanups in
  that driver, a CPPC cpufreq driver fix, and a some devfreq fixes and
  cleanups (core and exynos-nocp).

  Specifics:

   - Fix two cpufreq regressions causing undesirable changes in behavior
     to appear (one in the core and one in the conservative governor)
     introduced during the 4.8 cycle (Aaro Koskinen, Rafael Wysocki).

   - Fix the way the intel_pstate driver accesses MSRs related to the
     hardware-managed P-states (HWP) feature during the initialization
     which currently is unsafe and may cause the processor to generate a
     general protection fault (Srinivas Pandruvada).

   - Rework the intel_pstate's P-state selection algorithm used on Atom
     processors to avoid known problems with the current one and to make
     the computation more straightforward, which also happens to improve
     performance in multiple benchmarks a bit (Rafael Wysocki).

   - Improve two comments in the intel_pstate driver (Rafael Wysocki).

   - Fix the desired performance computation in the CPPC cpufreq driver
     (Hoan Tran).

   - Fix the devfreq core to avoid printing misleading error messages in
     some cases (Tobias Jakobi).

   - Fix the error code path in devfreq_add_device() to use proper
     locking around list modifications (Axel Lin).

   - Fix a build failure and remove a couple of redundant updates of
     variables in the exynos-nocp devfreq driver (Axel Lin)"

* tag 'pm-extra-4.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  cpufreq: CPPC: Correct desired_perf calculation
  cpufreq: conservative: Fix next frequency selection
  cpufreq: skip invalid entries when searching the frequency
  cpufreq: intel_pstate: Fix struct pstate_adjust_policy kerneldoc
  cpufreq: intel_pstate: Proportional algorithm for Atom
  PM / devfreq: Skip status update on uninitialized previous_freq
  PM / devfreq: Add proper locking around list_del()
  PM / devfreq: exynos-nocp: Remove redundant code
  PM / devfreq: exynos-nocp: Select REGMAP_MMIO
  cpufreq: intel_pstate: Clarify comment in get_target_pstate_use_performance()
  cpufreq: intel_pstate: Fix unsafe HWP MSR access
2016-10-14 12:46:13 -07:00
Hoan Tran c197d75803 cpufreq: CPPC: Correct desired_perf calculation
The desired_perf is an abstract performance number. Its value should
be in the range of [lowest perf, highest perf] of CPPC.
The correct calculation is
  desired_perf = freq * cppc_highest_perf / cppc_dmi_max_khz

And cppc_cpufreq_set_target() returns if desired_perf is exactly
the same with the old perf.

Signed-off-by: Hoan Tran <hotran@apm.com>
Reviewed-by: Prashanth Prakash <pprakash@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-10-13 23:10:41 +02:00
Linus Torvalds 72d39926f0 ACPI material for v4.9-rc1
- Update of the ACPICA code in the kernel to upstream revision 20160831 with
    the following major changes:
    * New mechanism for GPE masking.
    * Fixes for issues related to the LoadTable operator and table loading.
    * Fixes for issues related to so-called module-level code (MLC), that is
      AML that doesn't belong to any methods.
    * Change of the return value of the _OSI method to reflect the Windows
      behavior.
    * GAS (Generic Address Structure) support fix related to 32-bit FADT
      addresses.
    * Elimination of unnecessary FADT version 2 support.
    * ACPI tools fixes and cleanups.
    From Bob Moore, Lv Zheng, and Jung-uk Kim.
 
  - ACPI sysfs interface updates to fix GPE handling (on top of the new GPE
    masking mechanism in ACPICA) and issues related to table loading (Lv Zheng).
 
  - New watchdog driver based on the ACPI WDAT (ACPI Watchdog Action Table),
    needed on some platforms to replace the iTCO watchdog that doesn't work there
    and related updates of the intel_pmc_ipc, i2c/i801 and MFD/lcp_ich drivers
    (Mika Westerberg).
 
  - Driver core fix to prevent it from leaking secondary fwnode objects during
    device removal (Lukas Wunner).
 
  - New definitions of built-in properties for UART in ACPI-based x86 SoC drivers
    and a 8250_dw driver quirk for the APM X-Gene SoC (Heikki Krogerus).
 
  - New device ID for the Vulcan SPI controller and constification of local
    strucures in the AMD SoC (APD) ACPI driver (Kamlakant Patel, Julia Lawall).
 
  - Fix for a bug causing the allocation of PCI resorces to fail if
    ACPI-enumerated child platform devices are registered below the PCI
    devices in question (Mika Westerberg).
 
  - Change of the default polarity for PCI legacy IRQs to high on systems
    booting wth ACPI on platforms with a GIC interrupt controller model
    fixing the discrepancy between the specification and HW behavior (Lorenzo
    Pieralisi).
 
  - Fixes for the handling of system suspend/resume in the ACPI EC driver and
    update of that driver to make it cope with the cases when the EC device
    defined in the ECDT has to be used throughout the entire system life cycle
    (Lv Zheng).
 
  - Update of the ACPI CPPC library to allow it to batch requests sent over the
    PCC channel (to reduce overhead), to support the fixed functional hardware
    (FFH) CPPC registers access type, to notify the mailbox framework about TX
    completions when the interrupt flag is set for the PCC mailbox, and to
    support HW-Reduced Communication Subspace type 2 (Ashwin Chaugule, Prashanth
    Prakash, Srinivas Pandruvada, Hoan Tran).
 
  - ACPI button driver fix and documentation update related to the handling of
    laptop lids (Lv Zheng).
 
  - ACPI battery driver initialization fix (Carlos Garnacho).
 
  - ACPI GPIO enumeration documentation update (Mika Westerberg).
 
  - Assorted updates of the core ACPI bus type code (Lukas Wunner, Lv Zheng).
 
  - Assorted cleanups of the ACPI table parsing code and the x86-specific ACPI
    code (Al Stone).
 
  - Fixes for assorted ACPI-related issues found in linux-next (Wei Yongjun).
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Merge tag 'acpi-4.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull ACPI updates from Rafael Wysocki:
 "First off, the ACPICA code in the kernel is updated to upstream
  revision 20160831 that brings in a few bug fixes and cleanups. In
  particular, it is possible to mask GPEs now (and the sysfs interface
  for GPE control is fixed on top of that), problems related to the
  table loading mechanism are fixed and all code related to FADT version
  2 (which has never been part of the ACPI specification) is dropped.

  On the new features front, there is a new watchdog driver based on the
  ACPI WDAT (ACPI Watchdog Action Table), needed on some platforms to
  replace the iTCO watchdog that doesn't work there, and some UART
  devices get new definitions of built-in properties (to be accessed via
  the generic device properties API).

  Also, included is a fix for an ACPI-related PCI resorces allocation
  issue and a few problems in the EC driver and in the button and
  battery drivers are fixed.

  In addition to that, the ACPI CPPC library is updated to make batching
  of requests sent over the PCC channel possible (which reduces the PCC
  usage overhead substantially in some cases) and to support functional
  fixed hardware (FFH) type of CPPC registers access (which will allow
  CPPC to be used on x86 too in the future).

  As usual, there are some assorted fixes and cleanups too.

  Specifics:

   - Update of the ACPICA code in the kernel to upstream revision
     20160831 with the following major changes:

      * New mechanism for GPE masking.
      * Fixes for issues related to the LoadTable operator and table
        loading.
      * Fixes for issues related to so-called module-level code (MLC),
        that is AML that doesn't belong to any methods.
      * Change of the return value of the _OSI method to reflect the
        Windows behavior.
      * GAS (Generic Address Structure) support fix related to 32-bit
        FADT addresses.
      * Elimination of unnecessary FADT version 2 support.
      * ACPI tools fixes and cleanups.

     From Bob Moore, Lv Zheng, and Jung-uk Kim.

   - ACPI sysfs interface updates to fix GPE handling (on top of the new
     GPE masking mechanism in ACPICA) and issues related to table
     loading (Lv Zheng).

   - New watchdog driver based on the ACPI WDAT (ACPI Watchdog Action
     Table), needed on some platforms to replace the iTCO watchdog that
     doesn't work there and related updates of the intel_pmc_ipc,
     i2c/i801 and MFD/lcp_ich drivers (Mika Westerberg).

   - Driver core fix to prevent it from leaking secondary fwnode objects
     during device removal (Lukas Wunner).

   - New definitions of built-in properties for UART in ACPI-based x86
     SoC drivers and a 8250_dw driver quirk for the APM X-Gene SoC
     (Heikki Krogerus).

   - New device ID for the Vulcan SPI controller and constification of
     local strucures in the AMD SoC (APD) ACPI driver (Kamlakant Patel,
     Julia Lawall).

   - Fix for a bug causing the allocation of PCI resorces to fail if
     ACPI-enumerated child platform devices are registered below the PCI
     devices in question (Mika Westerberg).

   - Change of the default polarity for PCI legacy IRQs to high on
     systems booting wth ACPI on platforms with a GIC interrupt
     controller model fixing the discrepancy between the specification
     and HW behavior (Lorenzo Pieralisi).

   - Fixes for the handling of system suspend/resume in the ACPI EC
     driver and update of that driver to make it cope with the cases
     when the EC device defined in the ECDT has to be used throughout
     the entire system life cycle (Lv Zheng).

   - Update of the ACPI CPPC library to allow it to batch requests sent
     over the PCC channel (to reduce overhead), to support the fixed
     functional hardware (FFH) CPPC registers access type, to notify the
     mailbox framework about TX completions when the interrupt flag is
     set for the PCC mailbox, and to support HW-Reduced Communication
     Subspace type 2 (Ashwin Chaugule, Prashanth Prakash, Srinivas
     Pandruvada, Hoan Tran).

   - ACPI button driver fix and documentation update related to the
     handling of laptop lids (Lv Zheng).

   - ACPI battery driver initialization fix (Carlos Garnacho).

   - ACPI GPIO enumeration documentation update (Mika Westerberg).

   - Assorted updates of the core ACPI bus type code (Lukas Wunner, Lv
     Zheng).

   - Assorted cleanups of the ACPI table parsing code and the
     x86-specific ACPI code (Al Stone).

   - Fixes for assorted ACPI-related issues found in linux-next (Wei
     Yongjun)"

* tag 'acpi-4.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (98 commits)
  ACPI / documentation: Use recommended name in GPIO property names
  watchdog: wdat_wdt: Fix warning for using 0 as NULL
  watchdog: wdat_wdt: fix return value check in wdat_wdt_probe()
  platform/x86: intel_pmc_ipc: Do not create iTCO watchdog when WDAT table exists
  i2c: i801: Do not create iTCO watchdog when WDAT table exists
  mfd: lpc_ich: Do not create iTCO watchdog when WDAT table exists
  ACPI / bus: Adjust ACPI subsystem initialization for new table loading mode
  ACPICA: Parser: Fix a regression in LoadTable support
  ACPICA: Tables: Fix "UNLOAD" code path lock issues
  ACPI / watchdog: Add support for WDAT hardware watchdog
  ACPI / platform: Pay attention to parent device's resources
  PCI: Add pci_find_resource()
  ACPI / CPPC: Support PCC with interrupt flag
  ACPI / sysfs: Update sysfs signature handling code
  ACPI / sysfs: Fix an issue for LoadTable opcode
  ACPICA: Tables: Fix a regression in acpi_tb_find_table()
  ACPI / tables: Remove duplicated include from tables.c
  ACPI / APD: constify local structures
  x86: ACPI: make variable names clearer in acpi_parse_madt_lapic_entries()
  x86: ACPI: remove extraneous white space after semicolon
  ...
2016-10-03 10:11:58 -07:00
Hoan Tran f89f4147f7 cpufreq: CPPC: Avoid overflow when calculating desired_perf
This patch fixes overflow issue when calculating the desired_perf.

Fixes: ad38677df4 (cpufreq: CPPC: Force reporting values in KHz to fix user space interface)
Signed-off-by: Hoan Tran <hotran@apm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-09-16 23:59:19 +02:00
Al Stone ad38677df4 cpufreq: CPPC: Force reporting values in KHz to fix user space interface
When CPPC is being used by ACPI on arm64, user space tools such as
cpupower report CPU frequency values from sysfs that are incorrect.

What the driver was doing was reporting the values given by ACPI tables
in whatever scale was used to provide them.  However, the ACPI spec
defines the CPPC values as unitless abstract numbers.  Internal kernel
structures such as struct perf_cap, in contrast, expect these values
to be in KHz.  When these struct values get reported via sysfs, the
user space tools also assume they are in KHz, causing them to report
incorrect values (for example, reporting a CPU frequency of 1MHz when
it should be 1.8GHz).

The downside is that this approach has some assumptions:

   (1) It relies on SMBIOS3 being used, *and* that the Max Frequency
   value for a processor is set to a non-zero value.

   (2) It assumes that all processors run at the same speed, or that
   the CPPC values have all been scaled to reflect relative speed.
   This patch retrieves the largest CPU Max Frequency from a type 4 DMI
   record that it can find.  This may not be an issue, however, as a
   sampling of DMI data on x86 and arm64 indicates there is often only
   one such record regardless.  Since CPPC is relatively new, it is
   unclear if the ACPI ASL will always be written to reflect any sort
   of relative performance of processors of differing speeds.

   (3) It assumes that performance and frequency both scale linearly.

For arm64 servers, this may be sufficient, but it does rely on
firmware values being set correctly.  Hence, other approaches will
be considered in the future.

This has been tested on three arm64 servers, with and without DMI, with
and without CPPC support.

Signed-off-by: Al Stone <ahs3@redhat.com>
Signed-off-by: Prashanth Prakash <pprakash@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-09-13 02:47:44 +02:00
Srinivas Pandruvada 41dd640389 ACPI / CPPC: Add prefix cppc to cpudata structure name
Since struct cpudata is defined in a header file, add prefix cppc_ to
make it not a generic name. Otherwise it causes compile issue in locally
define structure with the same name.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-09-08 23:02:15 +02:00
Prakash, Prashanth be8b88d7d9 ACPI / CPPC: set a non-zero value for transition_latency
Compute the expected transition latency for frequency transitions
using the values from the PCCT tables when the desired perf
register is in PCC.

Signed-off-by: Prashanth Prakash <pprakash@codeaurora.org>
Reviewed-by: Alexey Klimov <alexey.klimov@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-08-31 01:02:33 +02:00
Ashwin Chaugule a29a1e7678 cpufreq: ACPI / CPPC: Add module support for cppc_cpufreq driver
Add a function to cleanup at module exit and export
appropriate GPL string to enable moduler support
for the cppc_cpufreq driver.

Reported-by: Srinivas Pandruvada <srinivas.pandruvada@intel.com>
Signed-off-by: Ashwin Chaugule <ashwin.chaugule@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-04-25 15:59:35 +02:00
Ashwin Chaugule 9dc1791773 cpufreq: CPPC: Initialize and check CPUFreq CPU co-ord type correctly
The CPU policy struct indicates the co-ordination type
for all CPUs of a common freq domain. Initialize it
correctly using the CPU specific data gathered from
CPPC ACPI lib via acpi_get_psd_map().

The PSD object is optional, so the cpu->shared_type
can also be 0. So instead of assuming any value other
than SW_ANY(0xFD) is unsupported, explictly check
if shared_type is SW_ALL and then bail.

Signed-off-by: Ashwin Chaugule <ashwin.chaugule@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-11-23 22:21:18 +01:00
Markus Elfring efb2d3be53 cpufreq: CPPC: Delete an unnecessary check before the function call kfree()
The kfree() function tests whether its argument is NULL and then
returns immediately. Thus the test around the call is not needed.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-11-07 00:03:18 +01:00
Ashwin Chaugule 5477fb3bd1 ACPI / CPPC: Add a CPUFreq driver for use with CPPC
This driver utilizes the methods introduced in a previous
patch titled - "ACPI: Introduce CPU performance controls using CPPC"
and enables usage with existing CPUFreq governors.

Signed-off-by: Ashwin Chaugule <ashwin.chaugule@linaro.org>
Reviewed-by: Al Stone <al.stone@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-10-12 23:04:31 +02:00