Commit Graph

231 Commits

Author SHA1 Message Date
Rafael J. Wysocki 3baad65546 Merge branch 'pm-cpufreq'
* pm-cpufreq:
  cpufreq: dt: Add support for APM X-Gene 2
  cpufreq: intel_pstate: Always keep all limits settings in sync
  cpufreq: intel_pstate: Use locking in intel_cpufreq_verify_policy()
  cpufreq: intel_pstate: Use locking in intel_pstate_resume()
  cpufreq: intel_pstate: Do not expose PID parameters in passive mode
2017-01-06 14:34:52 +01:00
Rafael J. Wysocki 111b8b3fe4 cpufreq: intel_pstate: Always keep all limits settings in sync
Make intel_pstate update per-logical-CPU limits when the global
settings are changed to ensure that they are always in sync and
users will not see confusing values in per-logical-CPU sysfs
attributes.

This also fixes the problem that setting the "no_turbo" global
attribute to 1 in the "passive" mode (ie. when intel_pstate acts
as a regular cpufreq driver) when scaling_governor is set to
"performance" has no effect.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
2016-12-31 21:48:44 +01:00
Rafael J. Wysocki cad3046796 cpufreq: intel_pstate: Use locking in intel_cpufreq_verify_policy()
Race conditions are possible if intel_cpufreq_verify_policy()
is executed in parallel with global limits updates from sysfs,
so the invocation of intel_pstate_update_perf_limits() in it
should be carried out under intel_pstate_limits_lock.

Make that happen.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
2016-12-31 21:48:43 +01:00
Rafael J. Wysocki aa439248ab cpufreq: intel_pstate: Use locking in intel_pstate_resume()
Theoretically, intel_pstate_resume() may be executed in parallel
with intel_pstate_set_policy(), if the latter is invoked via
cpufreq_update_policy() as a result of a notification, so use
intel_pstate_limits_lock in there too to avoid race conditions.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
2016-12-31 21:48:42 +01:00
Rafael J. Wysocki 366430b5c2 cpufreq: intel_pstate: Do not expose PID parameters in passive mode
If intel_pstate works in the passive mode in which it acts as
a regular cpufreq driver and collaborates with generic cpufreq
governors, the PID parameters are not used, so do not expose
them via debugfs in that case.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-12-27 03:30:11 +01:00
Linus Torvalds 7b9dc3f75f Power management material for v4.10-rc1
- New cpufreq driver for Broadcom STB SoCs and a Device Tree binding
    for it (Markus Mayer).
 
  - Support for ARM Integrator/AP and Integrator/CP in the generic
    DT cpufreq driver and elimination of the old Integrator cpufreq
    driver (Linus Walleij).
 
  - Support for the zx296718, r8a7743 and r8a7745, Socionext UniPhier,
    and PXA SoCs in the the generic DT cpufreq driver (Baoyou Xie,
    Geert Uytterhoeven, Masahiro Yamada, Robert Jarzmik).
 
  - cpufreq core fix to eliminate races that may lead to using
    inactive policy objects and related cleanups (Rafael Wysocki).
 
  - cpufreq schedutil governor update to make it use SCHED_FIFO
    kernel threads (instead of regular workqueues) for doing delayed
    work (to reduce the response latency in some cases) and related
    cleanups (Viresh Kumar).
 
  - New cpufreq sysfs attribute for resetting statistics (Markus
    Mayer).
 
  - cpufreq governors fixes and cleanups (Chen Yu, Stratos Karafotis,
    Viresh Kumar).
 
  - Support for using generic cpufreq governors in the intel_pstate
    driver (Rafael Wysocki).
 
  - Support for per-logical-CPU P-state limits and the EPP/EPB
    (Energy Performance Preference/Energy Performance Bias) knobs
    in the intel_pstate driver (Srinivas Pandruvada).
 
  - New CPU ID for Knights Mill in intel_pstate (Piotr Luc).
 
  - intel_pstate driver modification to use the P-state selection
    algorithm based on CPU load on platforms with the system profile
    in the ACPI tables set to "mobile" (Srinivas Pandruvada).
 
  - intel_pstate driver cleanups (Arnd Bergmann, Rafael Wysocki,
    Srinivas Pandruvada).
 
  - cpufreq powernv driver updates including fast switching support
    (for the schedutil governor), fixes and cleanus (Akshay Adiga,
    Andrew Donnellan, Denis Kirjanov).
 
  - acpi-cpufreq driver rework to switch it over to the new CPU
    offline/online state machine (Sebastian Andrzej Siewior).
 
  - Assorted cleanups in cpufreq drivers (Wei Yongjun, Prashanth
    Prakash).
 
  - Idle injection rework (to make it use the regular idle path
    instead of a home-grown custom one) and related powerclamp
    thermal driver updates (Peter Zijlstra, Jacob Pan, Petr Mladek,
    Sebastian Andrzej Siewior).
 
  - New CPU IDs for Atom Z34xx and Knights Mill in intel_idle (Andy
    Shevchenko, Piotr Luc).
 
  - intel_idle driver cleanups and switch over to using the new CPU
    offline/online state machine (Anna-Maria Gleixner, Sebastian
    Andrzej Siewior).
 
  - cpuidle DT driver update to support suspend-to-idle properly
    (Sudeep Holla).
 
  - cpuidle core cleanups and misc updates (Daniel Lezcano, Pan Bian,
    Rafael Wysocki).
 
  - Preliminary support for power domains including CPUs in the
    generic power domains (genpd) framework and related DT bindings
    (Lina Iyer).
 
  - Assorted fixes and cleanups in the generic power domains (genpd)
    framework (Colin Ian King, Dan Carpenter, Geert Uytterhoeven).
 
  - Preliminary support for devices with multiple voltage regulators
    and related fixes and cleanups in the Operating Performance Points
    (OPP) library (Viresh Kumar, Masahiro Yamada, Stephen Boyd).
 
  - System sleep state selection interface rework to make it easier
    to support suspend-to-idle as the default system suspend method
    (Rafael Wysocki).
 
  - PM core fixes and cleanups, mostly related to the interactions
    between the system suspend and runtime PM frameworks (Ulf Hansson,
    Sahitya Tummala, Tony Lindgren).
 
  - Latency tolerance PM QoS framework imorovements (Andrew
    Lutomirski).
 
  - New Knights Mill CPU ID for the Intel RAPL power capping driver
    (Piotr Luc).
 
  - Intel RAPL power capping driver fixes, cleanups and switch over
    to using the new CPU offline/online state machine (Jacob Pan,
    Thomas Gleixner, Sebastian Andrzej Siewior).
 
  - Fixes and cleanups in the exynos-ppmu, exynos-nocp, rk3399_dmc,
    rockchip-dfi devfreq drivers and the devfreq core (Axel Lin,
    Chanwoo Choi, Javier Martinez Canillas, MyungJoo Ham, Viresh
    Kumar).
 
  - Fix for false-positive KASAN warnings during resume from ACPI S3
    (suspend-to-RAM) on x86 (Josh Poimboeuf).
 
  - Memory map verification during resume from hibernation on x86 to
    ensure a consistent address space layout (Chen Yu).
 
  - Wakeup sources debugging enhancement (Xing Wei).
 
  - rockchip-io AVS driver cleanup (Shawn Lin).
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Merge tag 'pm-4.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management updates from Rafael Wysocki:
 "Again, cpufreq gets more changes than the other parts this time (one
  new driver, one old driver less, a bunch of enhancements of the
  existing code, new CPU IDs, fixes, cleanups)

  There also are some changes in cpuidle (idle injection rework, a
  couple of new CPU IDs, online/offline rework in intel_idle, fixes and
  cleanups), in the generic power domains framework (mostly related to
  supporting power domains containing CPUs), and in the Operating
  Performance Points (OPP) library (mostly related to supporting devices
  with multiple voltage regulators)

  In addition to that, the system sleep state selection interface is
  modified to make it easier for distributions with unchanged user space
  to support suspend-to-idle as the default system suspend method, some
  issues are fixed in the PM core, the latency tolerance PM QoS
  framework is improved a bit, the Intel RAPL power capping driver is
  cleaned up and there are some fixes and cleanups in the devfreq
  subsystem

  Specifics:

   - New cpufreq driver for Broadcom STB SoCs and a Device Tree binding
     for it (Markus Mayer)

   - Support for ARM Integrator/AP and Integrator/CP in the generic DT
     cpufreq driver and elimination of the old Integrator cpufreq driver
     (Linus Walleij)

   - Support for the zx296718, r8a7743 and r8a7745, Socionext UniPhier,
     and PXA SoCs in the the generic DT cpufreq driver (Baoyou Xie,
     Geert Uytterhoeven, Masahiro Yamada, Robert Jarzmik)

   - cpufreq core fix to eliminate races that may lead to using inactive
     policy objects and related cleanups (Rafael Wysocki)

   - cpufreq schedutil governor update to make it use SCHED_FIFO kernel
     threads (instead of regular workqueues) for doing delayed work (to
     reduce the response latency in some cases) and related cleanups
     (Viresh Kumar)

   - New cpufreq sysfs attribute for resetting statistics (Markus Mayer)

   - cpufreq governors fixes and cleanups (Chen Yu, Stratos Karafotis,
     Viresh Kumar)

   - Support for using generic cpufreq governors in the intel_pstate
     driver (Rafael Wysocki)

   - Support for per-logical-CPU P-state limits and the EPP/EPB (Energy
     Performance Preference/Energy Performance Bias) knobs in the
     intel_pstate driver (Srinivas Pandruvada)

   - New CPU ID for Knights Mill in intel_pstate (Piotr Luc)

   - intel_pstate driver modification to use the P-state selection
     algorithm based on CPU load on platforms with the system profile in
     the ACPI tables set to "mobile" (Srinivas Pandruvada)

   - intel_pstate driver cleanups (Arnd Bergmann, Rafael Wysocki,
     Srinivas Pandruvada)

   - cpufreq powernv driver updates including fast switching support
     (for the schedutil governor), fixes and cleanus (Akshay Adiga,
     Andrew Donnellan, Denis Kirjanov)

   - acpi-cpufreq driver rework to switch it over to the new CPU
     offline/online state machine (Sebastian Andrzej Siewior)

   - Assorted cleanups in cpufreq drivers (Wei Yongjun, Prashanth
     Prakash)

   - Idle injection rework (to make it use the regular idle path instead
     of a home-grown custom one) and related powerclamp thermal driver
     updates (Peter Zijlstra, Jacob Pan, Petr Mladek, Sebastian Andrzej
     Siewior)

   - New CPU IDs for Atom Z34xx and Knights Mill in intel_idle (Andy
     Shevchenko, Piotr Luc)

   - intel_idle driver cleanups and switch over to using the new CPU
     offline/online state machine (Anna-Maria Gleixner, Sebastian
     Andrzej Siewior)

   - cpuidle DT driver update to support suspend-to-idle properly
     (Sudeep Holla)

   - cpuidle core cleanups and misc updates (Daniel Lezcano, Pan Bian,
     Rafael Wysocki)

   - Preliminary support for power domains including CPUs in the generic
     power domains (genpd) framework and related DT bindings (Lina Iyer)

   - Assorted fixes and cleanups in the generic power domains (genpd)
     framework (Colin Ian King, Dan Carpenter, Geert Uytterhoeven)

   - Preliminary support for devices with multiple voltage regulators
     and related fixes and cleanups in the Operating Performance Points
     (OPP) library (Viresh Kumar, Masahiro Yamada, Stephen Boyd)

   - System sleep state selection interface rework to make it easier to
     support suspend-to-idle as the default system suspend method
     (Rafael Wysocki)

   - PM core fixes and cleanups, mostly related to the interactions
     between the system suspend and runtime PM frameworks (Ulf Hansson,
     Sahitya Tummala, Tony Lindgren)

   - Latency tolerance PM QoS framework imorovements (Andrew Lutomirski)

   - New Knights Mill CPU ID for the Intel RAPL power capping driver
     (Piotr Luc)

   - Intel RAPL power capping driver fixes, cleanups and switch over to
     using the new CPU offline/online state machine (Jacob Pan, Thomas
     Gleixner, Sebastian Andrzej Siewior)

   - Fixes and cleanups in the exynos-ppmu, exynos-nocp, rk3399_dmc,
     rockchip-dfi devfreq drivers and the devfreq core (Axel Lin,
     Chanwoo Choi, Javier Martinez Canillas, MyungJoo Ham, Viresh Kumar)

   - Fix for false-positive KASAN warnings during resume from ACPI S3
     (suspend-to-RAM) on x86 (Josh Poimboeuf)

   - Memory map verification during resume from hibernation on x86 to
     ensure a consistent address space layout (Chen Yu)

   - Wakeup sources debugging enhancement (Xing Wei)

   - rockchip-io AVS driver cleanup (Shawn Lin)"

* tag 'pm-4.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (127 commits)
  devfreq: rk3399_dmc: Don't use OPP structures outside of RCU locks
  devfreq: rk3399_dmc: Remove dangling rcu_read_unlock()
  devfreq: exynos: Don't use OPP structures outside of RCU locks
  Documentation: intel_pstate: Document HWP energy/performance hints
  cpufreq: intel_pstate: Support for energy performance hints with HWP
  cpufreq: intel_pstate: Add locking around HWP requests
  PM / sleep: Print active wakeup sources when blocking on wakeup_count reads
  PM / core: Fix bug in the error handling of async suspend
  PM / wakeirq: Fix dedicated wakeirq for drivers not using autosuspend
  PM / Domains: Fix compatible for domain idle state
  PM / OPP: Don't WARN on multiple calls to dev_pm_opp_set_regulators()
  PM / OPP: Allow platform specific custom set_opp() callbacks
  PM / OPP: Separate out _generic_set_opp()
  PM / OPP: Add infrastructure to manage multiple regulators
  PM / OPP: Pass struct dev_pm_opp_supply to _set_opp_voltage()
  PM / OPP: Manage supply's voltage/current in a separate structure
  PM / OPP: Don't use OPP structure outside of rcu protected section
  PM / OPP: Reword binding supporting multiple regulators per device
  PM / OPP: Fix incorrect cpu-supply property in binding
  cpuidle: Add a kerneldoc comment to cpuidle_use_deepest_state()
  ..
2016-12-13 10:41:53 -08:00
Srinivas Pandruvada 984edbdccc cpufreq: intel_pstate: Support for energy performance hints with HWP
It is possible to provide hints to the HWP algorithms in the processor
to be more performance centric to more energy centric. These hints are
provided by using HWP energy performance preference (EPP) or energy
performance bias (EPB) settings.

The scope of these settings is per logical processor, which means that
each of the logical processors in the package can be programmed with a
different value.

This change provides cpufreq sysfs interface to provide hint. For each
policy, two additional attributes will be available to check and provide
hint. These attributes will only be present when the intel_pstate driver
is using HWP mode.

These attributes are:
 - energy_performance_available_preferences
 - energy_performance_preference

To get list of supported hints:
$ cat energy_performance_available_preferences
default performance balance_performance balance_power power

The current preference can be read or changed via cpufreq sysfs
attribute "energy_performance_preference". Reading from this attribute
will display current effective setting changed via any method. User can
write any of the valid preference string to this attribute. User can
always restore to power-on default by writing "default".

Implementation
Since these hints can be provided by direct MSR write or using some tools
like x86_energy_perf_policy, the driver internally doesn't maintain any
state. The user operation will result in direct read/write of MSR: 0x774
(HWP_REQUEST_MSR). Also driver use read modify write to update other
fields in this MSR.

Summary of changes:
 - struct cpudata field epp_saved is renamed to epp_powersave, as this
   stores the value to restore once policy is switched from performance
   to powersave to restore original powersave EPP value.
 - A new struct cpudata field epp_saved is used to store the raw MSR
   EPP/EPB value when a CPU goes offline or on suspend and restore on
   online/resume. This ensures that EPP value is restored to correct
   value irrespective of the means used to set.
 - EPP/EPB value ranges are fixed for each preference, which can be
   set for the cpufreq sysfs, so user request is mapped to/from this
   range.
 - New attributes are only added when HWP is present.
 - Since EPP value of 0 is valid the fields are initialized to
   -EINVAL when not valid. The field epp_default is read only once
   after powerup to avoid reading on subsequent CPU online operation
 - New suspend callback to store epp on suspend operation
 - Don't invalidate old epp_saved field on resume and online as now
   we can restore last epp value on suspend and this field can still
   have old EPP value sampled during switch to performance from
   powersave.
 - While here optimized setting of cpu_data->epp_powersave = epp in
   intel_pstate_hwp_set() as this was done in both true and false
   paths.
 - epp/epb set function returns error to caller on failure to pass
   on to user space for display.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-12-08 01:43:05 +01:00
Srinivas Pandruvada b59fe54053 cpufreq: intel_pstate: Add locking around HWP requests
To avoid race conditions from multiple threads, increase the scope
of intel_pstate_limits_lock to include HWP requests also.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
[ rjw: Subject ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-12-08 01:43:04 +01:00
Piotr Luc 58bf454272 cpufreq: intel_pstate: Add Knights Mill CPUID
Add Knights Mill (KNM) to the list of CPUIDs supported by intel_pstate.

Signed-off-by: Piotr Luc <piotr.luc@intel.com>
Reviewed-by: Dave Hansen <dave.hansen@intel.com>
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-12-01 15:08:12 +01:00
Arnd Bergmann 7a3ba767f6 cpufreq: intel_pstate: fix intel_pstate_exit_perf_limits() prototype
The addition of the generic governor support marked the
intel_pstate_exit_perf_limits as inline(), which fixed a warning,
but it introduced another warning:

drivers/cpufreq/intel_pstate.c: In function ‘intel_pstate_exit_perf_limits’:
drivers/cpufreq/intel_pstate.c:483:1: error: no return statement in function returning non-void [-Werror=return-type]

This changes it back to a 'void' return type, and changes the
corresponding intel_pstate_init_acpi_perf_limits() function to
be inline as well for consistency.

Fixes: 001c76f05b (cpufreq: intel_pstate: Generic governors support)
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-11-28 14:24:21 +01:00
Srinivas Pandruvada 8442885fca cpufreq: intel_pstate: Set EPP/EPB to 0 in performance mode
When user has selected performance policy, then set the EPP (Energy
Performance Preference) or EPB (Energy Performance Bias) to maximum
performance mode.

Also when user switch back to powersave, then restore EPP/EPB to last
EPP/EPB value before entering performance mode. If user has not changed
EPP/EPB manually then it will be power on default value.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-11-28 14:23:56 +01:00
Rafael J. Wysocki 17669006ad cpufreq/intel_pstate: Use CPPC to get max performance
Use the acpi cppc_lib interface to get CPPC performance limits and update
the per cpu priority for the ITMT scheduler. If the highest performance of
CPUs differs the ITMT feature is enabled.

Co-developed-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Tim Chen <tim.c.chen@linux.intel.com>
Cc: linux-pm@vger.kernel.org
Cc: peterz@infradead.org
Cc: jolsa@redhat.com
Cc: rjw@rjwysocki.net
Cc: linux-acpi@vger.kernel.org
Cc: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Cc: bp@suse.de
Link: http://lkml.kernel.org/r/0998b98943bcdec7d1ddd4ff27358da555ea8e92.1479844244.git.tim.c.chen@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-11-24 20:44:20 +01:00
Srinivas Pandruvada d5dd33d9de cpufreq: intel_pstate: increase precision of performance limits
Even with round up of limits->min_perf and limits->max_perf, in some
cases resultant performance is 100 MHz less than the desired.

For example when the maximum frequency is 3.50 GHz, setting
scaling_min_frequency to 2.3 GHz always results in 2.2 GHz minimum.

Currently the fixed floating point operation uses 8 bit precision for
calculating limits->min_perf and limits->max_perf. For some operations
in this driver the 14 bit precision is used. Using the 14 bit precision
also for calculating limits->min_perf and limits->max_perf, addresses
this issue.

Introduced fp_ext_toint() equivalent to fp_toint() and int_ext_tofp()
equivalent to int_tofp() with 14 bit precision.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-11-22 02:31:49 +01:00
Srinivas Pandruvada 46992d6b55 cpufreq: intel_pstate: round up min_perf limits
In some use cases, user wants to enforce a minimum performance limit on
CPUs. But because of simple division the resultant performance is 100 MHz
less than the desired in some cases.

For example when the maximum frequency is 3.50 GHz, setting
scaling_min_frequency to 1.6 GHz always results in 1.5 GHz minimum. With
simple round up, the frequency can be set to 1.6 GHz to minimum in this
case. This round up is already done to max_policy_pct and max_perf, so do
the same for min_policy_pct and min_perf.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-11-22 02:31:48 +01:00
Rafael J. Wysocki 001c76f05b cpufreq: intel_pstate: Generic governors support
There may be reasons to use generic cpufreq governors (eg. schedutil)
on Intel platforms instead of the intel_pstate driver's internal
governor.  However, that currently can only be done by disabling
intel_pstate altogether and using the acpi-cpufreq driver instead
of it, which is subject to limitations.

First of all, acpi-cpufreq only works on systems where the _PSS
object is present in the ACPI tables for all logical CPUs.  Second,
on those systems acpi-cpufreq will only use frequencies listed by
_PSS which may be suboptimal.  In particular, by convention, the
whole turbo range is represented in _PSS as a single P-state and
the frequency assigned to it is greater by 1 MHz than the greatest
non-turbo frequency listed by _PSS.  That may confuse governors to
use turbo frequencies less frequently which may lead to suboptimal
performance.

For this reason, make it possible to use the intel_pstate driver
with generic cpufreq governors as a "normal" cpufreq driver.  That
mode is enforced by adding intel_pstate=passive to the kernel
command line and cannot be disabled at run time.  In that mode,
intel_pstate provides a cpufreq driver interface including
the ->target() and ->fast_switch() callbacks and is listed in
scaling_driver as "intel_cpufreq".

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Doug Smythies <dsmythies@telus.net>
2016-11-21 14:32:32 +01:00
Rafael J. Wysocki d0ea59e188 cpufreq: intel_pstate: Request P-states control from SMM if needed
Currently, intel_pstate is unable to control P-states on my
IvyBridge-based Acer Aspire S5, because they are controlled by SMM
on that machine by default and it is necessary to request OS control
of P-states from it via the SMI Command register exposed in the ACPI
FADT.  intel_pstate doesn't do that now, but acpi-cpufreq and other
cpufreq drivers for x86 platforms do.

Address this problem by making intel_pstate use the ACPI-defined
mechanism as well.  However, intel_pstate is not modular and it
doesn't need the module refcount tricks played by
acpi_processor_notify_smm(), so export the core of this function
to it as acpi_processor_pstate_control() and make it call that.
[The changes in processor_perflib.c related to this should not
make any functional difference for the acpi_processor_notify_smm()
users].

To be safe, only call acpi_processor_notify_smm() from intel_pstate
if ACPI _PPC support is enabled in it.

Suggested-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
2016-11-17 22:47:47 +01:00
Srinivas Pandruvada 7f7a516ee3 cpufreq: intel_pstate: Use CPU load based algorithm for PM_MOBILE
Use get_target_pstate_use_cpu_load() to calculate target P-State for
devices, with the preferred power management profile in ACPI FADT
set to PM_MOBILE.

This may help in resolving some thermal issues caused by low sustained
cpu bound workloads. The current algorithm tend to over provision in this
case as it doesn't look at the CPU busyness.

Also included the fix from Arnd Bergmann <arnd@arndb.de> to solve compile
issue, when CONFIG_ACPI is not defined.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-11-14 21:25:23 +01:00
Srinivas Pandruvada a410c03d66 cpufreq: intel_pstate: protect limits variable
The limits variable gets modified from intel_pstate sysfs and also gets
modified from cpufreq sysfs. So protect with a mutex to keep data
integrity, when they are getting modified from multiple threads.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-11-01 06:10:54 +01:00
Srinivas Pandruvada 5879f87739 cpufreq: intel_pstate: Reduce impact due to rounding error
When policy->max and policy->min are same, in some cases they don't
result in the same frequency cap. The max_policy_pct is rounded up but
not min_perf_pct. So even when they are same, results in different
percentage or maximum and minimum.
Since minimum is a conservative value for power, a lower value without
rounding is better in most of the cases, unless user wants
policy->max = policy->min.
This change uses use the same policy percentage when policy->max and
policy->min are same.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-11-01 06:04:06 +01:00
Srinivas Pandruvada eae48f046f cpufreq: intel_pstate: Per CPU P-State limits
Intel P-State offers two interface to set performance limits:
- Intel P-State sysfs
	/sys/devices/system/cpu/intel_pstate/max_perf_pct
	/sys/devices/system/cpu/intel_pstate/min_perf_pct
- cpufreq
	/sys/devices/system/cpu/cpu*/cpufreq/scaling_max_freq
	/sys/devices/system/cpu/cpu*/cpufreq/scaling_min_freq

In the current implementation both of the above methods, change limits
to every CPU in the system. Moreover the limits placed using cpufreq
policy interface also presented in the Intel P-State sysfs via modified
max_perf_pct and min_per_pct during sysfs reads. This allows to check
percent of reduced/increased performance, irrespective of method used to
limit.

There are some new generations of processors, where it is possible to
have limits placed on individual CPU cores. Using cpufreq interface it
is possible to set limits on each CPU. But the current processing will
use last limits placed on all CPUs. So the per core limit feature of
CPUs can't be used.

This change brings in capability to set P-States limits for each CPU,
with some limitations. In this case what should be the read of
max_perf_pct and min_perf_pct? It can be most restrictive limits placed
on any CPU or max possible performance on any given CPU on which no
limits are placed. In either case someone will have issue.

So the consensus is, we can't have both sysfs controls present when user
wants to use limit per core limits.
- By default per-core-control feature is not enabled. So no one will
notice any difference.
- The way to enable is by kernel command line
intel_pstate=per_cpu_perf_limits
- When the per-core-controls are enabled there is no display of for both
read and write on
	/sys/devices/system/cpu/intel_pstate/max_perf_pct
	/sys/devices/system/cpu/intel_pstate/min_perf_pct
- User can change limits using
	/sys/devices/system/cpu/cpu*/cpufreq/scaling_max_freq
	/sys/devices/system/cpu/cpu*/cpufreq/scaling_min_freq
	/sys/devices/system/cpu/cpu*/cpufreq/scaling_governor
- User can still observe turbo percent and number of P-States from
	/sys/devices/system/cpu/intel_pstate/turbo_pct
	/sys/devices/system/cpu/intel_pstate/num_pstates
- User can read write system wide turbo status
	/sys/devices/system/cpu/no_turbo

While changing this BUG_ON is changed to WARN_ON, as they are not fatal
errors for the system.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-11-01 06:04:06 +01:00
Rafael J. Wysocki fe0f59c412 Merge back earlier cpufreq material for v4.10. 2016-10-30 06:12:50 +01:00
Rafael J. Wysocki 2f1d407ada cpufreq: intel_pstate: Always set max P-state in performance mode
The only times at which intel_pstate checks the policy set for
a given CPU is the initialization of that CPU and updates of its
policy settings from cpufreq when intel_pstate_set_policy() is
invoked.

That is insufficient, however, because intel_pstate uses the same
P-state selection function for all CPUs regardless of the policy
setting for each of them and the P-state limits are shared between
them.  Thus if the policy is set to "performance" for a particular
CPU, it may not behave as expected if the cpufreq settings are
changed subsequently for another CPU.

That can be easily demonstrated by writing "performance" to
scaling_governor for all CPUs and then switching it to "powersave"
for one of them in which case all of the CPUs will behave as though
their scaling_governor were all "powersave" (even though the policy
still appears to be "performance" for the remaining CPUs).

Fix this problem by modifying intel_pstate_adjust_busy_pstate() to
always set the P-state to the maximum allowed by the current limits
for all CPUs whose policy is set to "performance".

Note that it still is recommended to always change the policy setting
in the same way for all CPUs even with this fix applied to avoid
confusion.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-10-24 23:20:25 +02:00
Rafael J. Wysocki a6c6ead141 cpufreq: intel_pstate: Set P-state upfront in performance mode
After commit a4675fbc4a (cpufreq: intel_pstate: Replace timers with
utilization update callbacks) the cpufreq governor callbacks may not
be invoked on NOHZ_FULL CPUs and, in particular, switching to the
"performance" policy via sysfs may not have any effect on them.  That
is a problem, because it usually is desirable to squeeze the last
bit of performance out of those CPUs, so work around it by setting
the maximum P-state (within the limits) in intel_pstate_set_policy()
upfront when the policy is CPUFREQ_POLICY_PERFORMANCE.

Fixes: a4675fbc4a (cpufreq: intel_pstate: Replace timers with utilization update callbacks)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
2016-10-21 22:18:22 +02:00
Srinivas Pandruvada 185d82456e cpufreq: intel_pstate: Remove PID debugfs when not used
When target state is calculated using get_target_pstate_use_cpu_load(),
PID controller is not used, hence it has no effect on performance.
So don't present debugfs entries to tune PID controller.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-10-21 22:16:26 +02:00
Rafael J. Wysocki 1d29815ef2 cpufreq: intel_pstate: Drop boost_iowait flag
The "IOwait boosting" mechanism is only used by the
get_target_pstate_use_cpu_load() governor function and the
boost_iowait flag in pid_params is always set when that function
is in use (and it is never set otherwise).  This means that the
boost_iowait flag is in fact redundant and may be dropped.

For this reason, replace the boost_iowait flag check in
intel_pstate_update_util() with an equivalent check against
pstate_funcs.get_target_pstate and drop that flag.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
2016-10-21 22:13:51 +02:00
Rafael J. Wysocki 3954517e2f cpufreq: intel_pstate: Fix struct pstate_adjust_policy kerneldoc
It looks like the name of struct pstate_adjust_policy was updated
without updating its kerneldoc comment accordingly, so fix that
mistake.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-10-12 20:58:14 +02:00
Rafael J. Wysocki 0843e83c1a cpufreq: intel_pstate: Proportional algorithm for Atom
The PID algorithm used by the intel_pstate driver tends to drive
performance to the minimum for workloads with utilization below the
setpoint, which is undesirable, so replace it with a modified
"proportional" algorithm on Atom.

The new algorithm will set the new P-state to be 1.25 times the
available maximum times the (frequency-invariant) utilization during
the previous sampling period except when the target P-state computed
this way is lower than the average P-state during the previous
sampling period.  In the latter case, it will increase the target by
50% of the difference between it and the average P-state to prevent
performance from dropping down too fast in some cases.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
2016-10-12 20:58:13 +02:00
Rafael J. Wysocki f00593a4bd cpufreq: intel_pstate: Clarify comment in get_target_pstate_use_performance()
Make the comment explaining the meaning of the perf_scaled variable
in get_target_pstate_use_performance() more straightforward.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-10-09 18:54:57 +02:00
Srinivas Pandruvada f9f4872df6 cpufreq: intel_pstate: Fix unsafe HWP MSR access
This is a requirement that MSR MSR_PM_ENABLE must be set to 0x01 before
reading MSR_HWP_CAPABILITIES on a given CPU. If cpufreq init() is
scheduled on a CPU which is not same as policy->cpu or migrates to a
different CPU before calling msr read for MSR_HWP_CAPABILITIES, it
is possible that MSR_PM_ENABLE was not to set to 0x01 on that CPU.
This will cause GP fault. So like other places in this path
rdmsrl_on_cpu should be used instead of rdmsrl.

Moreover the scope of MSR_HWP_CAPABILITIES is on per thread basis, so it
should be read from the same CPU, for which MSR MSR_HWP_REQUEST is
getting set.

dmesg dump or warning:

[   22.014488] WARNING: CPU: 139 PID: 1 at arch/x86/mm/extable.c:50 ex_handler_rdmsr_unsafe+0x68/0x70
[   22.014492] unchecked MSR access error: RDMSR from 0x771
[   22.014493] Modules linked in:
[   22.014507] CPU: 139 PID: 1 Comm: swapper/0 Not tainted 4.7.5+ #1
...
...
[   22.014516] Call Trace:
[   22.014542]  [<ffffffff813d7dd1>] dump_stack+0x63/0x82
[   22.014558]  [<ffffffff8107bc8b>] __warn+0xcb/0xf0
[   22.014561]  [<ffffffff8107bcff>] warn_slowpath_fmt+0x4f/0x60
[   22.014563]  [<ffffffff810676f8>] ex_handler_rdmsr_unsafe+0x68/0x70
[   22.014564]  [<ffffffff810677d9>] fixup_exception+0x39/0x50
[   22.014604]  [<ffffffff8102e400>] do_general_protection+0x80/0x150
[   22.014610]  [<ffffffff817f9ec8>] general_protection+0x28/0x30
[   22.014635]  [<ffffffff81687940>] ? get_target_pstate_use_performance+0xb0/0xb0
[   22.014642]  [<ffffffff810600c7>] ? native_read_msr+0x7/0x40
[   22.014657]  [<ffffffff81688123>] intel_pstate_hwp_set+0x23/0x130
[   22.014660]  [<ffffffff81688406>] intel_pstate_set_policy+0x1b6/0x340
[   22.014662]  [<ffffffff816829bb>] cpufreq_set_policy+0xeb/0x2c0
[   22.014664]  [<ffffffff81682f39>] cpufreq_init_policy+0x79/0xe0
[   22.014666]  [<ffffffff81682cb0>] ? cpufreq_update_policy+0x120/0x120
[   22.014669]  [<ffffffff816833a6>] cpufreq_online+0x406/0x820
[   22.014671]  [<ffffffff8168381f>] cpufreq_add_dev+0x5f/0x90
[   22.014717]  [<ffffffff81530ac8>] subsys_interface_register+0xb8/0x100
[   22.014719]  [<ffffffff816821bc>] cpufreq_register_driver+0x14c/0x210
[   22.014749]  [<ffffffff81fe1d90>] intel_pstate_init+0x39d/0x4d5
[   22.014751]  [<ffffffff81fe13f2>] ? cpufreq_gov_dbs_init+0x12/0x12

Cc: 4.3+ <stable@vger.kernel.org> # 4.3+
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-10-09 18:54:13 +02:00
Rafael J. Wysocki b6e2511782 Merge branch 'pm-cpufreq-sched' into pm-cpufreq 2016-10-02 01:42:33 +02:00
Srinivas Pandruvada 3ba7bcaa36 cpufreq: intel_pstate: Add io_boost trace
Add io_boost percent to current pstate_sample tracepoint.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-09-16 23:55:30 +02:00
Rafael J. Wysocki 09c448d3c6 cpufreq: intel_pstate: Use IOWAIT flag in Atom algorithm
Modify the P-state selection algorithm for Atom processors to use
the new SCHED_CPUFREQ_IOWAIT flag instead of the questionable
get_cpu_iowait_time_us() function.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-09-14 02:28:13 +02:00
Julia Lawall 42ce8921cc intel_pstate: constify local structures
For structure types defined in the same file or local header files, find
top-level static structure declarations that have the following
properties:
1. Never reassigned.
2. Address never taken
3. Not passed to a top-level macro call
4. No pointer or array-typed field passed to a function or stored in a
variable.
Declare structures having all of these properties as const.

Done using Coccinelle.
Based on a suggestion by Joe Perches <joe@perches.com>.

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-09-13 02:40:24 +02:00
Rafael J. Wysocki 58919e83c8 cpufreq / sched: Pass flags to cpufreq_update_util()
It is useful to know the reason why cpufreq_update_util() has just
been called and that can be passed as flags to cpufreq_update_util()
and to the ->func() callback in struct update_util_data.  However,
doing that in addition to passing the util and max arguments they
already take would be clumsy, so avoid it.

Instead, use the observation that the schedutil governor is part
of the scheduler proper, so it can access scheduler data directly.
This allows the util and max arguments of cpufreq_update_util()
and the ->func() callback in struct update_util_data to be replaced
with a flags one, but schedutil has to be modified to follow.

Thus make the schedutil governor obtain the CFS utilization
information from the scheduler and use the "RT" and "DL" flags
instead of the special utilization value of ULONG_MAX to track
updates from the RT and DL sched classes.  Make it non-modular
too to avoid having to export scheduler variables to modules at
large.

Next, update all of the other users of cpufreq_update_util()
and the ->func() callback in struct update_util_data accordingly.

Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2016-08-16 22:14:55 +02:00
Rafael J. Wysocki e2b3b80de5 Merge branches 'pm-sleep', 'pm-cpufreq', 'pm-core' and 'pm-opp'
* pm-sleep:
  x86/power/64: Do not refer to __PAGE_OFFSET from assembly code

* pm-cpufreq:
  cpufreq: Do not default-yes CPU_FREQ_STAT
  cpufreq: intel_pstate: Add more out-of-band IDs

* pm-core:
  PM-wakeup: Delete unnecessary checks before three function calls

* pm-opp:
  PM / OPP: optimize dev_pm_opp_set_rate() performance a bit
2016-08-05 15:46:55 +02:00
Srinivas Pandruvada 65c1262f40 cpufreq: intel_pstate: Add more out-of-band IDs
Add Skylake-X and Broadwell-X IDs for out-of-band (OBB) control of
P-States.

For these processors, if MSR_MISC_PWR_MGMT BIT(8) == 1, then the
Intel P-State driver should exit as OS can't control P-States.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
[ rjw : Subject/changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-07-28 23:58:17 +02:00
Rafael J. Wysocki bc841e260c Merge branch 'pm-cpu'
* pm-cpu:
  x86: remove duplicate turbo ratio limit MSRs
  tools/power turbostat: Replace MSR_NHM_TURBO_RATIO_LIMIT
  cpufreq: intel_pstate: Replace MSR_NHM_TURBO_RATIO_LIMIT
2016-07-25 13:46:30 +02:00
Srinivas Pandruvada da7de91c3e cpufreq: intel_pstate: Check cpuid for MSR_HWP_INTERRUPT
The MSR MSR_HWP_INTERRUPT is valid only when CPUID.06H:EAX[8] = 1, so
check for feature before accessing this MSR.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-07-21 14:29:30 +02:00
Rafael J. Wysocki bc95a454b6 intel_pstate: Update cpu_frequency tracepoint every time
Currently, intel_pstate only updates the cpu_frequency tracepoint
if the new P-state to set is different from the current one, but
that causes powertop to report 100% idle on an 100% loaded system
sometimes.

Prevent that from happening by updating the cpu_frequency tracepoint
every time intel_pstate_update_pstate() is called.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>-
2016-07-21 14:28:37 +02:00
Carsten Emde 2630abc243 cpufreq: intel_pstate: clean remnant struct element
When I was working with the Intel P state driver I came across a
remnant struct element that is no longer needed after the function
intel_pstate_calc_freq() was retired.

Signed-off-by: Carsten Emde <C.Emde@osadl.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-07-21 14:26:00 +02:00
Jan Kiszka 5fc8f707a2 intel_pstate: Fix MSR_CONFIG_TDP_x addressing in core_get_max_pstate()
If MSR_CONFIG_TDP_CONTROL is locked, we currently try to address some
MSR 0x80000648 or so. Mask out the relevant level bits 0 and 1.

Found while running over the Jailhouse hypervisor which became upset
about this strange MSR index.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Cc: 4.4+ <stable@vger.kernel.org> # 4.4+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-07-11 15:12:30 +02:00
Srinivas Pandruvada 100cf6f277 cpufreq: intel_pstate: Replace MSR_NHM_TURBO_RATIO_LIMIT
Replace MSR_NHM_TURBO_RATIO_LIMIT with MSR_TURBO_RATIO_LIMIT.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-07-07 15:31:58 +02:00
Rafael J. Wysocki 5d1191ab6c Merge back earlier cpufreq material for v4.8. 2016-07-04 13:21:43 +02:00
Jisheng Zhang 4a7cb7a96a intel_pstate: Declare pid_params/pstate_funcs/hwp_active __read_mostly
pid_params is written once by copy_pid_params() during initialization,
and thereafter is mostly read by hot path intel_pstate_update_util().
The read of pid_params gets more after commit a4675fbc4a ("cpufreq:
intel_pstate: Replace timers with utilization update callbacks")

pstate_funcs is written once by copy_cpu_funcs() during initialization,
and thereafter is mostly read by hot path intel_pstate_update_util()

hwp_active is written to once during initialization and thereafter is
mostly read by hot path intel_pstate_update_util().

The fact that they are mostly read and not written to makes them
candidates for __read_mostly declarations.

Signed-off-by: Jisheng Zhang <jszhang@marvell.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-06-28 00:04:04 +02:00
Jisheng Zhang 29327c84ba intel_pstate: add __init/__initdata marker to some functions/variables
These functions/variables are not needed after booting, so mark them
as __init or __initdata.

Signed-off-by: Jisheng Zhang <jszhang@marvell.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-06-28 00:04:04 +02:00
Jisheng Zhang eed436095e intel_pstate: Fix incorrect placement of __initdata
__initdata should be placed between the variable name and equal sign
(if there is) for the variable to be placed in the intended section.

Signed-off-by: Jisheng Zhang <jszhang@marvell.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-06-28 00:04:04 +02:00
Rafael J. Wysocki 5ab666e095 intel_pstate: Do not clear utilization update hooks on policy changes
intel_pstate_set_policy() is invoked by the cpufreq core during
driver initialization, on changes of policy attributes (minimim and
maximum frequency, for example) via sysfs and via CPU notifications
from the platform firmware.  On some platforms the latter may occur
relatively often.

Commit bb6ab52f2b (intel_pstate: Do not set utilization update hook
too early) made intel_pstate_set_policy() clear the CPU's utilization
update hook before updating the policy attributes for it (and set the
hook again after doind that), but that involves invoking
synchronize_sched() and adds overhead to the CPU notifications
mentioned above and to the sched-RCU handling in general.

That extra overhead is arguably not necessary, because updating
policy attributes when the CPU's utilization update hook is active
should not lead to any adverse effects, so drop the clearing of
the hook from intel_pstate_set_policy() and make it check if
the hook has been set already when attempting to set it.

Fixes: bb6ab52f2b (intel_pstate: Do not set utilization update hook too early)
Reported-by: Jisheng Zhang <jszhang@marvell.com>
Tested-by: Jisheng Zhang <jszhang@marvell.com>
Tested-by: Doug Smythies <dsmythies@telus.net>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-06-27 23:47:15 +02:00
Rafael J. Wysocki 56b7808572 Merge back earlier cpufreq changes for v4.8. 2016-06-20 14:31:41 +02:00
Srinivas Pandruvada b00345d199 cpufreq: intel_pstate: Adjust _PSS[0] freqeuency if needed
The maximum turbo P-State used by the intel_pstate driver may be
limited by ACPI _PSS table entry 0.  After commit 9522a2ff9c
(cpufreq: intel_pstate: Enforce _PPC limits), the maximum performance
on servers will be capped by the _PSS table entry 0 by default.

Even though that is formally correct, it may lead to preformance
regressions in some cases.  Namely, if the _PSS table entry 0 is
not the maximum turbo P-State, performance measured after commit
9522a2ff9c will not match the performance measured before that
commit on the same system.

For this reason, modify the code to always use the maximum turbo
frequency as the one that corresponds to _PSS table entry 0 if turbo
is enabled in the BIOS.  This way, the performance levels from
before commit 9522a2ff9c will be restored on the affected systems.

Fixes: 9522a2ff9c (cpufreq: intel_pstate: Enforce _PPC limits)
Suggested-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
[ rjw : Changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-06-15 01:56:47 +02:00
Srinivas Pandruvada 41bad47f76 cpufreq: intel_pstate: Broxton support
Add Broxton CPU model number.

Broxton requires core_params to get performance limits via MSRs, but
it is an Atom platform, which requires more power optimized algorithm.

So the P state selection will use similar algorithm as other Atom
platforms.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-06-13 23:49:39 +02:00