<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/drivers/cpufreq, branch v5.16.3</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>cpufreq: intel_pstate: Update cpuinfo.max_freq on HWP_CAP changes</title>
<updated>2022-01-27T11:02:28+00:00</updated>
<author>
<name>Rafael J. Wysocki</name>
<email>rafael.j.wysocki@intel.com</email>
</author>
<published>2021-12-17T19:06:08+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=1878c20ba82fe614f367476ff94a136f0aa5a22a'/>
<id>1878c20ba82fe614f367476ff94a136f0aa5a22a</id>
<content type='text'>
[ Upstream commit dfeeedc1bf5772226bddf51ed3f853e5a6707bf1 ]

With HWP enabled, when the turbo range of performance levels is
disabled by the platform firmware, the CPU capacity is given by
the "guaranteed performance" field in MSR_HWP_CAPABILITIES which
is generally dynamic.  When it changes, the kernel receives an HWP
notification interrupt handled by notify_hwp_interrupt().

When the "guaranteed performance" value changes in the above
configuration, the CPU performance scaling needs to be adjusted so
as to use the new CPU capacity in computations, which means that
the cpuinfo.max_freq value needs to be updated for that CPU.

Accordingly, modify intel_pstate_notify_work() to read
MSR_HWP_CAPABILITIES and update cpuinfo.max_freq to reflect the
new configuration (this update can be carried out even if the
configuration doesn't actually change, because it simply doesn't
matter then and it takes less time to update it than to do extra
checks to decide whether or not a change has really occurred).

Reported-by: Srinivas Pandruvada &lt;srinivas.pandruvada@linux.intel.com&gt;
Tested-by: Srinivas Pandruvada &lt;srinivas.pandruvada@linux.intel.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit dfeeedc1bf5772226bddf51ed3f853e5a6707bf1 ]

With HWP enabled, when the turbo range of performance levels is
disabled by the platform firmware, the CPU capacity is given by
the "guaranteed performance" field in MSR_HWP_CAPABILITIES which
is generally dynamic.  When it changes, the kernel receives an HWP
notification interrupt handled by notify_hwp_interrupt().

When the "guaranteed performance" value changes in the above
configuration, the CPU performance scaling needs to be adjusted so
as to use the new CPU capacity in computations, which means that
the cpuinfo.max_freq value needs to be updated for that CPU.

Accordingly, modify intel_pstate_notify_work() to read
MSR_HWP_CAPABILITIES and update cpuinfo.max_freq to reflect the
new configuration (this update can be carried out even if the
configuration doesn't actually change, because it simply doesn't
matter then and it takes less time to update it than to do extra
checks to decide whether or not a change has really occurred).

Reported-by: Srinivas Pandruvada &lt;srinivas.pandruvada@linux.intel.com&gt;
Tested-by: Srinivas Pandruvada &lt;srinivas.pandruvada@linux.intel.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>cpufreq: Fix initialization of min and max frequency QoS requests</title>
<updated>2022-01-27T11:02:25+00:00</updated>
<author>
<name>Rafael J. Wysocki</name>
<email>rafael.j.wysocki@intel.com</email>
</author>
<published>2021-12-16T19:32:15+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=f370288ea3044cd40d795f85226a6820b6b01ada'/>
<id>f370288ea3044cd40d795f85226a6820b6b01ada</id>
<content type='text'>
[ Upstream commit 521223d8b3ec078f670c7c35a1a04b1b2af07966 ]

The min and max frequency QoS requests in the cpufreq core are
initialized to whatever the current min and max frequency values are
at the init time, but if any of these values change later (for
example, cpuinfo.max_freq is updated by the driver), these initial
request values will be limiting the CPU frequency unnecessarily
unless they are changed by user space via sysfs.

To address this, initialize min_freq_req and max_freq_req to
FREQ_QOS_MIN_DEFAULT_VALUE and FREQ_QOS_MAX_DEFAULT_VALUE,
respectively, so they don't really limit anything until user
space updates them.

Reported-by: Srinivas Pandruvada &lt;srinivas.pandruvada@linux.intel.com&gt;
Tested-by: Srinivas Pandruvada &lt;srinivas.pandruvada@linux.intel.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 521223d8b3ec078f670c7c35a1a04b1b2af07966 ]

The min and max frequency QoS requests in the cpufreq core are
initialized to whatever the current min and max frequency values are
at the init time, but if any of these values change later (for
example, cpuinfo.max_freq is updated by the driver), these initial
request values will be limiting the CPU frequency unnecessarily
unless they are changed by user space via sysfs.

To address this, initialize min_freq_req and max_freq_req to
FREQ_QOS_MIN_DEFAULT_VALUE and FREQ_QOS_MAX_DEFAULT_VALUE,
respectively, so they don't really limit anything until user
space updates them.

Reported-by: Srinivas Pandruvada &lt;srinivas.pandruvada@linux.intel.com&gt;
Tested-by: Srinivas Pandruvada &lt;srinivas.pandruvada@linux.intel.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>cpufreq: qcom-hw: Fix probable nested interrupt handling</title>
<updated>2022-01-27T11:01:33+00:00</updated>
<author>
<name>Vladimir Zapolskiy</name>
<email>vladimir.zapolskiy@linaro.org</email>
</author>
<published>2021-11-11T15:48:07+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=9911ac27e96facd8dd2c8842e29aadc9859c80fe'/>
<id>9911ac27e96facd8dd2c8842e29aadc9859c80fe</id>
<content type='text'>
[ Upstream commit e0e27c3d4e20dab861566f1c348ae44e4b498630 ]

Re-enabling an interrupt from its own interrupt handler may cause
an interrupt storm, if there is a pending interrupt and because its
handling is disabled due to already done entrance into the handler
above in the stack.

Also, apparently it is improper to lock a mutex in an interrupt contex.

Fixes: 275157b367f4 ("cpufreq: qcom-cpufreq-hw: Add dcvs interrupt support")
Signed-off-by: Vladimir Zapolskiy &lt;vladimir.zapolskiy@linaro.org&gt;
Reviewed-by: Matthias Kaehlcke &lt;mka@chromium.org&gt;
Reviewed-by: Bjorn Andersson &lt;bjorn.andersson@linaro.org&gt;
Signed-off-by: Viresh Kumar &lt;viresh.kumar@linaro.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit e0e27c3d4e20dab861566f1c348ae44e4b498630 ]

Re-enabling an interrupt from its own interrupt handler may cause
an interrupt storm, if there is a pending interrupt and because its
handling is disabled due to already done entrance into the handler
above in the stack.

Also, apparently it is improper to lock a mutex in an interrupt contex.

Fixes: 275157b367f4 ("cpufreq: qcom-cpufreq-hw: Add dcvs interrupt support")
Signed-off-by: Vladimir Zapolskiy &lt;vladimir.zapolskiy@linaro.org&gt;
Reviewed-by: Matthias Kaehlcke &lt;mka@chromium.org&gt;
Reviewed-by: Bjorn Andersson &lt;bjorn.andersson@linaro.org&gt;
Signed-off-by: Viresh Kumar &lt;viresh.kumar@linaro.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>cpufreq: qcom-cpufreq-hw: Update offline CPUs per-cpu thermal pressure</title>
<updated>2022-01-27T11:01:33+00:00</updated>
<author>
<name>Lukasz Luba</name>
<email>lukasz.luba@arm.com</email>
</author>
<published>2021-11-09T19:57:12+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=966a596b5ea24614d29a7a853bab9d7261671c8e'/>
<id>966a596b5ea24614d29a7a853bab9d7261671c8e</id>
<content type='text'>
[ Upstream commit 93d9e6f93e1586fcc97498c764be2e8c8401f4bd ]

The thermal pressure signal gives information to the scheduler about
reduced CPU capacity due to thermal. It is based on a value stored in
a per-cpu 'thermal_pressure' variable. The online CPUs will get the
new value there, while the offline won't. Unfortunately, when the CPU
is back online, the value read from per-cpu variable might be wrong
(stale data).  This might affect the scheduler decisions, since it
sees the CPU capacity differently than what is actually available.

Fix it by making sure that all online+offline CPUs would get the
proper value in their per-cpu variable when there is throttling
or throttling is removed.

Fixes: 275157b367f479 ("cpufreq: qcom-cpufreq-hw: Add dcvs interrupt support")
Reviewed-by: Thara Gopinath &lt;thara.gopinath@linaro.org&gt;
Signed-off-by: Lukasz Luba &lt;lukasz.luba@arm.com&gt;
Signed-off-by: Viresh Kumar &lt;viresh.kumar@linaro.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 93d9e6f93e1586fcc97498c764be2e8c8401f4bd ]

The thermal pressure signal gives information to the scheduler about
reduced CPU capacity due to thermal. It is based on a value stored in
a per-cpu 'thermal_pressure' variable. The online CPUs will get the
new value there, while the offline won't. Unfortunately, when the CPU
is back online, the value read from per-cpu variable might be wrong
(stale data).  This might affect the scheduler decisions, since it
sees the CPU capacity differently than what is actually available.

Fix it by making sure that all online+offline CPUs would get the
proper value in their per-cpu variable when there is throttling
or throttling is removed.

Fixes: 275157b367f479 ("cpufreq: qcom-cpufreq-hw: Add dcvs interrupt support")
Reviewed-by: Thara Gopinath &lt;thara.gopinath@linaro.org&gt;
Signed-off-by: Lukasz Luba &lt;lukasz.luba@arm.com&gt;
Signed-off-by: Viresh Kumar &lt;viresh.kumar@linaro.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>cpufreq: Fix a comment in cpufreq_policy_free</title>
<updated>2021-12-01T19:02:11+00:00</updated>
<author>
<name>Tang Yizhou</name>
<email>tangyizhou@huawei.com</email>
</author>
<published>2021-12-01T07:40:20+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=1e81d3e06de24aedac5c27df13cfa40d912b221b'/>
<id>1e81d3e06de24aedac5c27df13cfa40d912b221b</id>
<content type='text'>
Make the comment in blocking_notifier_call_chain() easier to
understand.

Signed-off-by: Tang Yizhou &lt;tangyizhou@huawei.com&gt;
Acked-by: Viresh Kumar &lt;viresh.kumar@linaro.org&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Make the comment in blocking_notifier_call_chain() easier to
understand.

Signed-off-by: Tang Yizhou &lt;tangyizhou@huawei.com&gt;
Acked-by: Viresh Kumar &lt;viresh.kumar@linaro.org&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>cpufreq: Fix get_cpu_device() failure in add_cpu_dev_symlink()</title>
<updated>2021-12-01T18:50:56+00:00</updated>
<author>
<name>Xiongfeng Wang</name>
<email>wangxiongfeng2@huawei.com</email>
</author>
<published>2021-11-29T08:02:48+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=2c1b5a84669d2477d8fffe9136e86a2cff591729'/>
<id>2c1b5a84669d2477d8fffe9136e86a2cff591729</id>
<content type='text'>
When I hot added a CPU, I found 'cpufreq' directory was not created
below /sys/devices/system/cpu/cpuX/.

It is because get_cpu_device() failed in add_cpu_dev_symlink().

cpufreq_add_dev() is the .add_dev callback of a CPU subsys interface.
It will be called when the CPU device registered into the system.
The call chain is as follows:

  register_cpu()
  -&gt;device_register()
   -&gt;device_add()
    -&gt;bus_probe_device()
     -&gt;cpufreq_add_dev()

But only after the CPU device has been registered, we can get the
CPU device by get_cpu_device(), otherwise it will return NULL.

Since we already have the CPU device in cpufreq_add_dev(), pass
it to add_cpu_dev_symlink().

I noticed that the 'kobj' of the CPU device has been added into
the system before cpufreq_add_dev().

Fixes: 2f0ba790df51 ("cpufreq: Fix creation of symbolic links to policy directories")
Signed-off-by: Xiongfeng Wang &lt;wangxiongfeng2@huawei.com&gt;
Acked-by: Viresh Kumar &lt;viresh.kumar@linaro.org&gt;
Cc: All applicable &lt;stable@vger.kernel.org&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
When I hot added a CPU, I found 'cpufreq' directory was not created
below /sys/devices/system/cpu/cpuX/.

It is because get_cpu_device() failed in add_cpu_dev_symlink().

cpufreq_add_dev() is the .add_dev callback of a CPU subsys interface.
It will be called when the CPU device registered into the system.
The call chain is as follows:

  register_cpu()
  -&gt;device_register()
   -&gt;device_add()
    -&gt;bus_probe_device()
     -&gt;cpufreq_add_dev()

But only after the CPU device has been registered, we can get the
CPU device by get_cpu_device(), otherwise it will return NULL.

Since we already have the CPU device in cpufreq_add_dev(), pass
it to add_cpu_dev_symlink().

I noticed that the 'kobj' of the CPU device has been added into
the system before cpufreq_add_dev().

Fixes: 2f0ba790df51 ("cpufreq: Fix creation of symbolic links to policy directories")
Signed-off-by: Xiongfeng Wang &lt;wangxiongfeng2@huawei.com&gt;
Acked-by: Viresh Kumar &lt;viresh.kumar@linaro.org&gt;
Cc: All applicable &lt;stable@vger.kernel.org&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>cpufreq: intel_pstate: ITMT support for overclocked system</title>
<updated>2021-11-23T13:11:18+00:00</updated>
<author>
<name>Srinivas Pandruvada</name>
<email>srinivas.pandruvada@linux.intel.com</email>
</author>
<published>2021-11-19T05:18:01+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=03c83982a0278207709143ba78c5a470179febee'/>
<id>03c83982a0278207709143ba78c5a470179febee</id>
<content type='text'>
On systems with overclocking enabled, CPPC Highest Performance can be
hard coded to 0xff. In this case even if we have cores with different
highest performance, ITMT can't be enabled as the current implementation
depends on CPPC Highest Performance.

On such systems we can use MSR_HWP_CAPABILITIES maximum performance field
when CPPC.Highest Performance is 0xff.

Due to legacy reasons, we can't solely depend on MSR_HWP_CAPABILITIES as
in some older systems CPPC Highest Performance is the only way to identify
different performing cores.

Reported-by: Michael Larabel &lt;Michael@MichaelLarabel.com&gt;
Signed-off-by: Srinivas Pandruvada &lt;srinivas.pandruvada@linux.intel.com&gt;
Tested-by: Michael Larabel &lt;Michael@MichaelLarabel.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
On systems with overclocking enabled, CPPC Highest Performance can be
hard coded to 0xff. In this case even if we have cores with different
highest performance, ITMT can't be enabled as the current implementation
depends on CPPC Highest Performance.

On such systems we can use MSR_HWP_CAPABILITIES maximum performance field
when CPPC.Highest Performance is 0xff.

Due to legacy reasons, we can't solely depend on MSR_HWP_CAPABILITIES as
in some older systems CPPC Highest Performance is the only way to identify
different performing cores.

Reported-by: Michael Larabel &lt;Michael@MichaelLarabel.com&gt;
Signed-off-by: Srinivas Pandruvada &lt;srinivas.pandruvada@linux.intel.com&gt;
Tested-by: Michael Larabel &lt;Michael@MichaelLarabel.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>cpufreq: intel_pstate: Fix active mode offline/online EPP handling</title>
<updated>2021-11-23T13:02:11+00:00</updated>
<author>
<name>Rafael J. Wysocki</name>
<email>rafael.j.wysocki@intel.com</email>
</author>
<published>2021-11-17T13:57:31+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=ed38eb49d101e829ae0f8c0a0d3bf5cb6bcbc6b2'/>
<id>ed38eb49d101e829ae0f8c0a0d3bf5cb6bcbc6b2</id>
<content type='text'>
After commit 4adcf2e5829f ("cpufreq: intel_pstate: Add -&gt;offline and
-&gt;online callbacks") the EPP value set by the "performance" scaling
algorithm in the active mode is not restored after an offline/online
cycle which replaces it with the saved EPP value coming from user
space.

Address this issue by forcing intel_pstate_hwp_set() to set a new
EPP value when it runs first time after online.

Fixes: 4adcf2e5829f ("cpufreq: intel_pstate: Add -&gt;offline and -&gt;online callbacks")
Link: https://lore.kernel.org/linux-pm/adc7132c8655bd4d1c8b6129578e931a14fe1db2.camel@linux.intel.com/
Reported-by: Srinivas Pandruvada &lt;srinivas.pandruvada@linux.intel.com&gt;
Cc: 5.9+ &lt;stable@vger.kernel.org&gt; # 5.9+
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
After commit 4adcf2e5829f ("cpufreq: intel_pstate: Add -&gt;offline and
-&gt;online callbacks") the EPP value set by the "performance" scaling
algorithm in the active mode is not restored after an offline/online
cycle which replaces it with the saved EPP value coming from user
space.

Address this issue by forcing intel_pstate_hwp_set() to set a new
EPP value when it runs first time after online.

Fixes: 4adcf2e5829f ("cpufreq: intel_pstate: Add -&gt;offline and -&gt;online callbacks")
Link: https://lore.kernel.org/linux-pm/adc7132c8655bd4d1c8b6129578e931a14fe1db2.camel@linux.intel.com/
Reported-by: Srinivas Pandruvada &lt;srinivas.pandruvada@linux.intel.com&gt;
Cc: 5.9+ &lt;stable@vger.kernel.org&gt; # 5.9+
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>cpufreq: intel_pstate: Add Ice Lake server to out-of-band IDs</title>
<updated>2021-11-23T13:02:10+00:00</updated>
<author>
<name>Adamos Ttofari</name>
<email>attofari@amazon.de</email>
</author>
<published>2021-11-12T09:16:57+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=cd23f02f166892603eb9f2d488152b975872b682'/>
<id>cd23f02f166892603eb9f2d488152b975872b682</id>
<content type='text'>
Commit fbdc21e9b038 ("cpufreq: intel_pstate: Add Icelake servers
support in no-HWP mode") enabled the use of Intel P-State driver
for Ice Lake servers.

But it doesn't cover the case when OS can't control P-States.

Therefore, for Ice Lake server, if MSR_MISC_PWR_MGMT bits 8 or 18
are enabled, then the Intel P-State driver should exit as OS can't
control P-States.

Fixes: fbdc21e9b038 ("cpufreq: intel_pstate: Add Icelake servers support in no-HWP mode")
Signed-off-by: Adamos Ttofari &lt;attofari@amazon.de&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Commit fbdc21e9b038 ("cpufreq: intel_pstate: Add Icelake servers
support in no-HWP mode") enabled the use of Intel P-State driver
for Ice Lake servers.

But it doesn't cover the case when OS can't control P-States.

Therefore, for Ice Lake server, if MSR_MISC_PWR_MGMT bits 8 or 18
are enabled, then the Intel P-State driver should exit as OS can't
control P-States.

Fixes: fbdc21e9b038 ("cpufreq: intel_pstate: Add Icelake servers support in no-HWP mode")
Signed-off-by: Adamos Ttofari &lt;attofari@amazon.de&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>cpufreq: intel_pstate: Clear HWP Status during HWP Interrupt enable</title>
<updated>2021-11-04T18:48:47+00:00</updated>
<author>
<name>Srinivas Pandruvada</name>
<email>srinivas.pandruvada@linux.intel.com</email>
</author>
<published>2021-11-04T10:22:30+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=074d0cdfbb2f5985c5748fe80f6f8a2a7db8b63f'/>
<id>074d0cdfbb2f5985c5748fe80f6f8a2a7db8b63f</id>
<content type='text'>
It is possible that some performance excursions happened before OS boot
or enable HWP interrupts. So clear MSR_HWP_STATUS bits when we enable
HWP interrupt. In this way a next excursion will results in a HWP
interrupt.

The status bits of MSR_HWP_STATUS must be cleared (0) by software so
that a new status condition change will cause the hardware to set the
bit again and issue the notification.

Fixes: 57577c996d73 ("cpufreq: intel_pstate: Process HWP Guaranteed change notification")
Signed-off-by: Srinivas Pandruvada &lt;srinivas.pandruvada@linux.intel.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</content>
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<pre>
It is possible that some performance excursions happened before OS boot
or enable HWP interrupts. So clear MSR_HWP_STATUS bits when we enable
HWP interrupt. In this way a next excursion will results in a HWP
interrupt.

The status bits of MSR_HWP_STATUS must be cleared (0) by software so
that a new status condition change will cause the hardware to set the
bit again and issue the notification.

Fixes: 57577c996d73 ("cpufreq: intel_pstate: Process HWP Guaranteed change notification")
Signed-off-by: Srinivas Pandruvada &lt;srinivas.pandruvada@linux.intel.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</pre>
</div>
</content>
</entry>
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