History log of /openbmc/linux/drivers/cpufreq/acpi-cpufreq.c (Results 76 – 100 of 180)
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# f4fd3797 27-Jun-2013 Lan Tianyu <tianyu.lan@intel.com>

acpi-cpufreq: Add new sysfs attribute freqdomain_cpus

Commits fcf8058 (cpufreq: Simplify cpufreq_add_dev()) and aa77a52
(cpufreq: acpi-cpufreq: Don't set policy->related_cpus from .init())
changed t

acpi-cpufreq: Add new sysfs attribute freqdomain_cpus

Commits fcf8058 (cpufreq: Simplify cpufreq_add_dev()) and aa77a52
(cpufreq: acpi-cpufreq: Don't set policy->related_cpus from .init())
changed the contents of the "related_cpus" sysfs attribute on systems
where acpi-cpufreq is used and user space can't get the list of CPUs
which are in the same hardware coordination CPU domain (provided by
the ACPI AML method _PSD) via "related_cpus" any more.

To make up for that loss add a new sysfs attribute "freqdomian_cpus"
for the acpi-cpufreq driver which exposes the list of CPUs in the
same domain regardless of whether it is coordinated by hardware or
software.

[rjw: Changelog, documentation]
References: https://bugzilla.kernel.org/show_bug.cgi?id=58761
Reported-by: Jean-Philippe Halimi <jean-philippe.halimi@exascale-computing.eu>
Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

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# e15d8309 19-Jun-2013 Viresh Kumar <viresh.kumar@linaro.org>

cpufreq: ACPI: call CPUFREQ_POSTCHANGE notfier in error cases

PRECHANGE and POSTCHANGE notifiers must be called in groups, i.e either both
should be called or both shouldn't be.

In case we have sta

cpufreq: ACPI: call CPUFREQ_POSTCHANGE notfier in error cases

PRECHANGE and POSTCHANGE notifiers must be called in groups, i.e either both
should be called or both shouldn't be.

In case we have started PRECHANGE notifier and found an error, we
must call POSTCHANGE notifier with freqs.new = freqs.old to
guarantee that the sequence of calling notifiers is complete.

This patch fixes it.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

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# c655affb 07-Jun-2013 Rafael J. Wysocki <rafael.j.wysocki@intel.com>

ACPI / cpufreq: Add ACPI processor device IDs to acpi-cpufreq

After commit ac212b6 (ACPI / processor: Use common hotplug
infrastructure) the acpi-cpufreq module is not loaded automatically
by udev w

ACPI / cpufreq: Add ACPI processor device IDs to acpi-cpufreq

After commit ac212b6 (ACPI / processor: Use common hotplug
infrastructure) the acpi-cpufreq module is not loaded automatically
by udev which fails to match it against the x86cpu modalias. Still,
it can be matched against ACPI processor device IDs, which even
makes more sense, because it depends on the ACPI processor driver
that uses those device IDs to bind to processor devices.

For this reason, add ACPI processor device IDs to acpi-cpufreq.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>

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Revision tags: v3.10-rc4
# 8673b83b 31-May-2013 Ross Lagerwall <rosslagerwall@gmail.com>

acpi-cpufreq: set current frequency based on target P-State

Commit 4b31e774 (Always set P-state on initialization) fixed bug
#4634 and caused the driver to always set the target P-State at
least onc

acpi-cpufreq: set current frequency based on target P-State

Commit 4b31e774 (Always set P-state on initialization) fixed bug
#4634 and caused the driver to always set the target P-State at
least once since the initial P-State may not be the desired one.
Commit 5a1c0228 (cpufreq: Avoid calling cpufreq driver's target()
routine if target_freq == policy->cur) caused a regression in
this behavior.

This fixes the regression by setting policy->cur based on the CPU's
target frequency rather than the CPU's current reported frequency
(which may be different). This means that the P-State will be set
initially if the CPU's target frequency is different from the
governor's target frequency.

This fixes an issue where setting the default governor to
performance wouldn't correctly enable turbo mode on all cores.

Signed-off-by: Ross Lagerwall <rosslagerwall@gmail.com>
Reviewed-by: Len Brown <len.brown@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: 3.8+ <stable@vger.kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

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Revision tags: v3.10-rc3, v3.10-rc2, v3.10-rc1, v3.9, v3.9-rc8, v3.9-rc7, v3.9-rc6, v3.9-rc5
# 50701588 30-Mar-2013 Viresh Kumar <viresh.kumar@linaro.org>

cpufreq: rename index as driver_data in cpufreq_frequency_table

The "index" field of struct cpufreq_frequency_table was never an
index and isn't used at all by the cpufreq core. It only is useful
f

cpufreq: rename index as driver_data in cpufreq_frequency_table

The "index" field of struct cpufreq_frequency_table was never an
index and isn't used at all by the cpufreq core. It only is useful
for cpufreq drivers for their internal purposes.

Many people nowadays blindly set it in ascending order with the
assumption that the core will use it, which is a mistake.

Rename it to "driver_data" as that's what its purpose is. All of its
users are updated accordingly.

[rjw: Changelog]
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

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# 2361be23 17-May-2013 Viresh Kumar <viresh.kumar@linaro.org>

cpufreq: Don't create empty /sys/devices/system/cpu/cpufreq directory

When we don't have any file in cpu/cpufreq directory we shouldn't
create it. Specially with the introduction of per-policy gover

cpufreq: Don't create empty /sys/devices/system/cpu/cpufreq directory

When we don't have any file in cpu/cpufreq directory we shouldn't
create it. Specially with the introduction of per-policy governor
instance patchset, even governors are moved to
cpu/cpu*/cpufreq/governor-name directory and so this directory is
just not required.

Lets have it only when required.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

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# b43a7ffb 24-Mar-2013 Viresh Kumar <viresh.kumar@linaro.org>

cpufreq: Notify all policy->cpus in cpufreq_notify_transition()

policy->cpus contains all online cpus that have single shared clock line. And
their frequencies are always updated together.

Many SMP

cpufreq: Notify all policy->cpus in cpufreq_notify_transition()

policy->cpus contains all online cpus that have single shared clock line. And
their frequencies are always updated together.

Many SMP system's cpufreq drivers take care of this in individual drivers but
the best place for this code is in cpufreq core.

This patch modifies cpufreq_notify_transition() to notify frequency change for
all cpus in policy->cpus and hence updates all users of this API.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Stephen Warren <swarren@nvidia.com>
Tested-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

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# aa77a527 24-Mar-2013 Viresh Kumar <viresh.kumar@linaro.org>

cpufreq: acpi-cpufreq: Don't set policy->related_cpus from .init()

With the addition of following patch:

fcf8058 cpufreq: Simplify cpufreq_add_dev()

cpufreq driver's .init() routine must initializ

cpufreq: acpi-cpufreq: Don't set policy->related_cpus from .init()

With the addition of following patch:

fcf8058 cpufreq: Simplify cpufreq_add_dev()

cpufreq driver's .init() routine must initialize policy->cpus with
mask of all possible CPUs (Online + Offline) that share the clock.
Then the core would copy this mask onto policy->related_cpus and will
reset policy->cpus to carry only online cpus.

acpi-cpufreq driver wasn't updated with this assumption and so
sometimes when we try to hot[un]plug CPUs at run time, sysfs
directories get corrupted.

This patch fixes acpi-cpufreq driver against this corruption.

Reported-and-tested-by: Maciej Rutecki <maciej.rutecki@gmail.com>
Tested-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

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Revision tags: v3.9-rc4, v3.9-rc3, v3.9-rc2, v3.9-rc1, v3.8, v3.8-rc7, v3.8-rc6
# 2624f90c 31-Jan-2013 Fabio Baltieri <fabio.baltieri@linaro.org>

cpufreq: governors: implement generic policy_is_shared

Implement a generic helper function policy_is_shared() to replace the
current dbs_sw_coordinated_cpus() at cpufreq level, so that it can be
use

cpufreq: governors: implement generic policy_is_shared

Implement a generic helper function policy_is_shared() to replace the
current dbs_sw_coordinated_cpus() at cpufreq level, so that it can be
used by code other than cpufreq governors.

Suggested-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Fabio Baltieri <fabio.baltieri@linaro.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

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Revision tags: v3.8-rc5
# c40a4518 20-Jan-2013 Matthew Garrett <mjg59@srcf.ucam.org>

acpi-cpufreq: Do not load on K8

de3ed81d746d ("[CPUFREQ] Change link order of x86 cpufreq modules")
changed cpufreq drivers link order so that powernow-k8 gets loaded first
due to earlier K8s having

acpi-cpufreq: Do not load on K8

de3ed81d746d ("[CPUFREQ] Change link order of x86 cpufreq modules")
changed cpufreq drivers link order so that powernow-k8 gets loaded first
due to earlier K8s having BIOS bugs.

However, now that acpi-cpufreq supports both AMD and Intel CPUs with HW
P-states, we want to load it first, so that cases where acpi-cpufreq and
powernow-k8 are both built-in and powernow-k8 initializing first, can be
addressed.

So, make sure that even if acpi-cpufreq gets loaded first, it errors out
on K8s and powernow-k8 can be loaded then successfully.

Signed-off-by: Matthew Garrett <mjg59@srcf.ucam.org>
References: http://lkml.kernel.org/r/20130118162347.GA31499@srcf.ucam.org
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

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# efa17194 22-Jan-2013 Matthew Garrett <matthew.garrett@nebula.com>

cpufreq: Add module aliases for acpi-cpufreq

The acpi core will call request_module("acpi-cpufreq") on subsystem init,
but this will fail if the module isn't available at that stage of boot.
Add som

cpufreq: Add module aliases for acpi-cpufreq

The acpi core will call request_module("acpi-cpufreq") on subsystem init,
but this will fail if the module isn't available at that stage of boot.
Add some module aliases to ensure that udev can load the module on Intel
and AMD systems with the appropriate feature bits - I /think/ that this
will also work on VIA systems, but haven't verified that.

References: http://lkml.kernel.org/r/1448223.sdUJnNSRz4@vostro.rjw.lan
Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>
Tested-by: Leonid Isaev <lisaev@umail.iu.edu>
Acked-by: Borislav Petkov <bp@suse.de>
Cc: 3.7+ <stable@vger.kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

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Revision tags: v3.8-rc4, v3.8-rc3, v3.8-rc2, v3.8-rc1, v3.7, v3.7-rc8, v3.7-rc7, v3.7-rc6, v3.7-rc5, v3.7-rc4, v3.7-rc3, v3.7-rc2, v3.7-rc1, v3.6, v3.6-rc7, v3.6-rc6, v3.6-rc5
# 11269ff5 04-Sep-2012 Andre Przywara <andre.przywara@amd.com>

acpi-cpufreq: Add compatibility for legacy AMD cpb sysfs knob

The powernow-k8 driver supported a sysfs knob called "cpb", which was
instantiated per CPU, but actually acted globally for the whole
sy

acpi-cpufreq: Add compatibility for legacy AMD cpb sysfs knob

The powernow-k8 driver supported a sysfs knob called "cpb", which was
instantiated per CPU, but actually acted globally for the whole
system. To keep some compatibility with this feature, we re-introduce
this behavior here, but:
a) only enable it on AMD CPUs and
b) protect it with a Kconfig switch

I'd like to consider this feature obsolete. Lets keep it around for
some kernel versions and then phase it out.

Signed-off-by: Andre Przywara <andre.przywara@amd.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

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# 615b7300 04-Sep-2012 Andre Przywara <andre.przywara@amd.com>

acpi-cpufreq: Add support for disabling dynamic overclocking

One feature present in powernow-k8 that isn't present in acpi-cpufreq
is support for enabling or disabling AMD's core performance boost
t

acpi-cpufreq: Add support for disabling dynamic overclocking

One feature present in powernow-k8 that isn't present in acpi-cpufreq
is support for enabling or disabling AMD's core performance boost
technology. This patch adds support to acpi-cpufreq, but also
includes support for Intel's dynamic acceleration.

The original boost disabling sysfs file was per CPU, but acted
globally. Also the naming (cpb) was at least not intuitive.
So lets introduce a single file simply called "boost", which sits
once in /sys/devices/system/cpu/cpufreq.
This should be the only way of using this feature, so add
documentation about the rationale and the usage.

A following patch will re-introduce the cpb knob for compatibility
reasons on AMD CPUs.

Per-CPU boost switching is possible, but not trivial and is thus
postponed to a later patch series.

Signed-off-by: Andre Przywara <andre.przywara@amd.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

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# acd31624 04-Sep-2012 Andre Przywara <andre.przywara@amd.com>

acpi-cpufreq: Add quirk to disable _PSD usage on all AMD CPUs

To workaround some Windows specific behavior, the ACPI _PSD table
on AMD desktop boards advertises all cores as dependent, meaning
that

acpi-cpufreq: Add quirk to disable _PSD usage on all AMD CPUs

To workaround some Windows specific behavior, the ACPI _PSD table
on AMD desktop boards advertises all cores as dependent, meaning
that they all can only use the same P-state. acpi-cpufreq strictly
obeys this description, instantiating one CPU only and symlinking
the others. But the hardware can have distinct frequencies for each
core and powernow-k8 did it that way.
So, in order to use the hardware to its full potential and keep the
original powernow-k8 behavior, lets override the _PSD table setting
on AMD hardware.
We use the siblings table, as it matches the current hardware
behavior.

Signed-off-by: Andre Przywara <andre.przywara@amd.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

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# 3dc9a633 04-Sep-2012 Matthew Garrett <mjg@redhat.com>

acpi-cpufreq: Add support for modern AMD CPUs

The programming model for P-states on modern AMD CPUs is very similar to
that of Intel and VIA. It makes sense to consolidate this support into one
driv

acpi-cpufreq: Add support for modern AMD CPUs

The programming model for P-states on modern AMD CPUs is very similar to
that of Intel and VIA. It makes sense to consolidate this support into one
driver rather than duplicating functionality between two of them. This
patch adds support for AMDs with hardware P-state control to acpi-cpufreq.

Signed-off-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Andre Przywara <andre.przywara@amd.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

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Revision tags: v3.6-rc4, v3.6-rc3, v3.6-rc2, v3.6-rc1, v3.5, v3.5-rc7, v3.5-rc6, v3.5-rc5, v3.5-rc4, v3.5-rc3, v3.5-rc2, v3.5-rc1, v3.4, v3.4-rc7, v3.4-rc6, v3.4-rc5, v3.4-rc4, v3.4-rc3, v3.4-rc2, v3.4-rc1, v3.3, v3.3-rc7, v3.3-rc6, v3.3-rc5, v3.3-rc4, v3.3-rc3, v3.3-rc2, v3.3-rc1, v3.2, v3.2-rc7, v3.2-rc6, v3.2-rc5, v3.2-rc4, v3.2-rc3, v3.2-rc2, v3.2-rc1, v3.1, v3.1-rc10, v3.1-rc9, v3.1-rc8, v3.1-rc7, v3.1-rc6, v3.1-rc5, v3.1-rc4, v3.1-rc3, v3.1-rc2, v3.1-rc1, v3.0
# 92e03c41 13-Jul-2011 Matthew Garrett <mjg@redhat.com>

[CPUFREQ] Handle CPUs with different capabilities in acpi-cpufreq

acpi-cpufreq checks each CPU for aperf/mperf support, but only sets a
global flag. This will cause errors if some CPUs in the system

[CPUFREQ] Handle CPUs with different capabilities in acpi-cpufreq

acpi-cpufreq checks each CPU for aperf/mperf support, but only sets a
global flag. This will cause errors if some CPUs in the system don't
support the feature. Check boot_cpu_has() instead in order to make sure
that all CPUs support it.

Signed-off-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Dave Jones <davej@redhat.com>

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Revision tags: v3.0-rc7
# 50f4ddd4 08-Jul-2011 Luming Yu <luming.yu@gmail.com>

[CPUFREQ] fix cpumask memory leak in acpi-cpufreq on cpu hotplug.

I came across a memory leak during a cyclic cpu-online-offline test.

Signed-off-by: Yu Luming <luming.yu@intel.com>
Cc: Len Brown <

[CPUFREQ] fix cpumask memory leak in acpi-cpufreq on cpu hotplug.

I came across a memory leak during a cyclic cpu-online-offline test.

Signed-off-by: Yu Luming <luming.yu@intel.com>
Cc: Len Brown <lenb@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dave Jones <davej@redhat.com>

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Revision tags: v3.0-rc6, v3.0-rc5, v3.0-rc4, v3.0-rc3, v3.0-rc2, v3.0-rc1
# bb0a56ec 19-May-2011 Dave Jones <davej@redhat.com>

[CPUFREQ] Move x86 drivers to drivers/cpufreq/

Signed-off-by: Dave Jones <davej@redhat.com>


# 0a5fcc0a 15-Feb-2021 Rafael J. Wysocki <rafael.j.wysocki@intel.com>

cpufreq: ACPI: Set cpuinfo.max_freq directly if max boost is known

commit 538b0188da4653b9f4511a114f014354fb6fb7a5 upstream.

Commit 3c55e94c0ade ("cpufreq: ACPI: Extend frequency ta

cpufreq: ACPI: Set cpuinfo.max_freq directly if max boost is known

commit 538b0188da4653b9f4511a114f014354fb6fb7a5 upstream.

Commit 3c55e94c0ade ("cpufreq: ACPI: Extend frequency tables to cover
boost frequencies") attempted to address a performance issue involving
acpi-cpufreq, the schedutil governor and scale-invariance on x86 by
extending the frequency tables created by acpi-cpufreq to cover the
entire range of "turbo" (or "boost") frequencies, but that caused
frequencies reported via /proc/cpuinfo and the scaling_cur_freq
attribute in sysfs to change which may confuse users and monitoring
tools.

For this reason, revert the part of commit 3c55e94c0ade adding the
extra entry to the frequency table and use the observation that
in principle cpuinfo.max_freq need not be equal to the maximum
frequency listed in the frequency table for the given policy.

Namely, modify cpufreq_frequency_table_cpuinfo() to allow cpufreq
drivers to set their own cpuinfo.max_freq above that frequency and
change acpi-cpufreq to set cpuinfo.max_freq to the maximum boost
frequency found via CPPC.

This should be sufficient to let all of the cpufreq subsystem know
the real maximum frequency of the CPU without changing frequency
reporting.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=211305
Fixes: 3c55e94c0ade ("cpufreq: ACPI: Extend frequency tables to cover boost frequencies")
Reported-by: Matt McDonald <gardotd426@gmail.com>
Tested-by: Matt McDonald <gardotd426@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Giovanni Gherdovich <ggherdovich@suse.cz>
Tested-by: Michael Larabel <Michael@phoronix.com>
Cc: 5.11+ <stable@vger.kernel.org> # 5.11+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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# 18193e09 04-Feb-2021 Rafael J. Wysocki <rafael.j.wysocki@intel.com>

cpufreq: ACPI: Update arch scale-invariance max perf ratio if CPPC is not there

commit d11a1d08a082a7dc0ada423d2b2e26e9b6f2525c upstream.

If the maximum performance level taken for

cpufreq: ACPI: Update arch scale-invariance max perf ratio if CPPC is not there

commit d11a1d08a082a7dc0ada423d2b2e26e9b6f2525c upstream.

If the maximum performance level taken for computing the
arch_max_freq_ratio value used in the x86 scale-invariance code is
higher than the one corresponding to the cpuinfo.max_freq value
coming from the acpi_cpufreq driver, the scale-invariant utilization
falls below 100% even if the CPU runs at cpuinfo.max_freq or slightly
faster, which causes the schedutil governor to select a frequency
below cpuinfo.max_freq. That frequency corresponds to a frequency
table entry below the maximum performance level necessary to get to
the "boost" range of CPU frequencies which prevents "boost"
frequencies from being used in some workloads.

While this issue is related to scale-invariance, it may be amplified
by commit db865272d9c4 ("cpufreq: Avoid configuring old governors as
default with intel_pstate") from the 5.10 development cycle which
made it extremely easy to default to schedutil even if the preferred
driver is acpi_cpufreq as long as intel_pstate is built too, because
the mere presence of the latter effectively removes the ondemand
governor from the defaults. Distro kernels are likely to include
both intel_pstate and acpi_cpufreq on x86, so their users who cannot
use intel_pstate or choose to use acpi_cpufreq may easily be
affectecd by this issue.

If CPPC is available, it can be used to address this issue by
extending the frequency tables created by acpi_cpufreq to cover the
entire available frequency range (including "boost" frequencies) for
each CPU, but if CPPC is not there, acpi_cpufreq has no idea what
the maximum "boost" frequency is and the frequency tables created by
it cannot be extended in a meaningful way, so in that case make it
ask the arch scale-invariance code to to use the "nominal" performance
level for CPU utilization scaling in order to avoid the issue at hand.

Fixes: db865272d9c4 ("cpufreq: Avoid configuring old governors as default with intel_pstate")
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Giovanni Gherdovich <ggherdovich@suse.cz>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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# 8a3fc32b 04-Feb-2021 Rafael J. Wysocki <rafael.j.wysocki@intel.com>

cpufreq: ACPI: Extend frequency tables to cover boost frequencies

commit 3c55e94c0adea4a5389c4b80f6ae9927dd6a4501 upstream.

A severe performance regression on AMD EPYC processors wh

cpufreq: ACPI: Extend frequency tables to cover boost frequencies

commit 3c55e94c0adea4a5389c4b80f6ae9927dd6a4501 upstream.

A severe performance regression on AMD EPYC processors when using
the schedutil scaling governor was discovered by Phoronix.com and
attributed to the following commits:

41ea667227ba ("x86, sched: Calculate frequency invariance for AMD
systems")

976df7e5730e ("x86, sched: Use midpoint of max_boost and max_P for
frequency invariance on AMD EPYC")

The source of the problem is that the maximum performance level taken
for computing the arch_max_freq_ratio value used in the x86 scale-
invariance code is higher than the one corresponding to the
cpuinfo.max_freq value coming from the acpi_cpufreq driver.

This effectively causes the scale-invariant utilization to fall below
100% even if the CPU runs at cpuinfo.max_freq or slightly faster, so
the schedutil governor selects a frequency below cpuinfo.max_freq
then. That frequency corresponds to a frequency table entry below
the maximum performance level necessary to get to the "boost" range
of CPU frequencies.

However, if the cpuinfo.max_freq value coming from acpi_cpufreq was
higher, the schedutil governor would select higher frequencies which
in turn would allow acpi_cpufreq to set more adequate performance
levels and to get to the "boost" range of CPU frequencies more often.

This issue affects any systems where acpi_cpufreq is used and the
"boost" (or "turbo") frequencies are enabled, not just AMD EPYC.
Moreover, commit db865272d9c4 ("cpufreq: Avoid configuring old
governors as default with intel_pstate") from the 5.10 development
cycle made it extremely easy to default to schedutil even if the
preferred driver is acpi_cpufreq as long as intel_pstate is built
too, because the mere presence of the latter effectively removes the
ondemand governor from the defaults. Distro kernels are likely to
include both intel_pstate and acpi_cpufreq on x86, so their users
who cannot use intel_pstate or choose to use acpi_cpufreq may
easily be affectecd by this issue.

To address this issue, extend the frequency table constructed by
acpi_cpufreq for each CPU to cover the entire range of available
frequencies (including the "boost" ones) if CPPC is available and
indicates that "boost" (or "turbo") frequencies are enabled. That
causes cpuinfo.max_freq to become the maximum "boost" frequency of
the given CPU (instead of the maximum frequency returned by the ACPI
_PSS object that corresponds to the "nominal" performance level).

Fixes: 41ea667227ba ("x86, sched: Calculate frequency invariance for AMD systems")
Fixes: 976df7e5730e ("x86, sched: Use midpoint of max_boost and max_P for frequency invariance on AMD EPYC")
Fixes: db865272d9c4 ("cpufreq: Avoid configuring old governors as default with intel_pstate")
Link: https://www.phoronix.com/scan.php?page=article&item=linux511-amd-schedutil&num=1
Link: https://lore.kernel.org/linux-pm/20210203135321.12253-2-ggherdovich@suse.cz/
Reported-by: Michael Larabel <Michael@phoronix.com>
Diagnosed-by: Giovanni Gherdovich <ggherdovich@suse.cz>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Giovanni Gherdovich <ggherdovich@suse.cz>
Reviewed-by: Giovanni Gherdovich <ggherdovich@suse.cz>
Tested-by: Michael Larabel <Michael@phoronix.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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Revision tags: v5.10, v5.8.17
# 5368512a 18-Oct-2020 Wei Huang <wei.huang2@amd.com>

acpi-cpufreq: Honor _PSD table setting on new AMD CPUs

acpi-cpufreq has a old quirk that overrides the _PSD table supplied by
BIOS on AMD CPUs. However the _PSD table of new AMD CPUs (Fa

acpi-cpufreq: Honor _PSD table setting on new AMD CPUs

acpi-cpufreq has a old quirk that overrides the _PSD table supplied by
BIOS on AMD CPUs. However the _PSD table of new AMD CPUs (Family 19h+)
now accurately reports the P-state dependency of CPU cores. Hence this
quirk needs to be fixed in order to support new CPUs' frequency control.

Fixes: acd316248205 ("acpi-cpufreq: Add quirk to disable _PSD usage on all AMD CPUs")
Signed-off-by: Wei Huang <wei.huang2@amd.com>
[ rjw: Subject edit ]
Cc: 3.10+ <stable@vger.kernel.org> # 3.10+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

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Revision tags: v5.8.16, v5.8.15, v5.9, v5.8.14, v5.8.13, v5.8.12, v5.8.11, v5.8.10, v5.8.9, v5.8.8, v5.8.7, v5.8.6, v5.4.62, v5.8.5, v5.8.4, v5.4.61, v5.8.3, v5.4.60, v5.8.2, v5.4.59, v5.8.1, v5.4.58, v5.4.57, v5.4.56, v5.8, v5.7.12, v5.4.55, v5.7.11, v5.4.54, v5.7.10, v5.4.53, v5.4.52, v5.7.9
# a7b90937 15-Jul-2020 Lee Jones <lee.jones@linaro.org>

cpufreq: acpi-cpufreq: Mark sometimes used ID structs as __maybe_unused

Not used when MODULE is not defined.

Fixes the following W=1 kernel build warning(s):

drivers/cpufr

cpufreq: acpi-cpufreq: Mark sometimes used ID structs as __maybe_unused

Not used when MODULE is not defined.

Fixes the following W=1 kernel build warning(s):

drivers/cpufreq/acpi-cpufreq.c:1004:36: warning: ‘processor_device_ids’ defined but not used [-Wunused-const-variable=]
997 | static const struct x86_cpu_id acpi_cpufreq_ids[] = {
| ^~~~~~~~~~~~~~~~
drivers/cpufreq/acpi-cpufreq.c:997:32: warning: ‘acpi_cpufreq_ids’ defined but not used [-Wunused-const-variable=]
619 | static const struct acpi_device_id processor_device_ids[] = {
| ^~~~~~~~~~~~~~~~~~~~

Signed-off-by: Lee Jones <lee.jones@linaro.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

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# e1711f29 15-Jul-2020 Lee Jones <lee.jones@linaro.org>

cpufreq: acpi-cpufreq: Mark 'dummy' variable as __always_unused

If we fail to use a variable, even a 'dummy' one, then the compiler
complains that it is set but not used. We know this i

cpufreq: acpi-cpufreq: Mark 'dummy' variable as __always_unused

If we fail to use a variable, even a 'dummy' one, then the compiler
complains that it is set but not used. We know this is fine, so we
set it as __always_unused to let the compiler know.

Fixes the following W=1 kernel build warning(s):

drivers/cpufreq/acpi-cpufreq.c: In function ‘cpu_freq_read_intel’:
drivers/cpufreq/acpi-cpufreq.c:247:11: warning: variable ‘dummy’ set but not used [-Wunused-but-set-variable]
drivers/cpufreq/acpi-cpufreq.c: In function ‘cpu_freq_read_amd’:
drivers/cpufreq/acpi-cpufreq.c:265:11: warning: variable ‘dummy’ set but not used [-Wunused-but-set-variable]

Signed-off-by: Lee Jones <lee.jones@linaro.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

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# 8479eb82 13-Jul-2020 Alexander A. Klimov <grandmaster@al2klimov.de>

cpufreq: Replace HTTP links with HTTPS ones

Rationale:
Reduces attack surface on kernel devs opening the links for MITM
as HTTPS traffic is much harder to manipulate.

Determ

cpufreq: Replace HTTP links with HTTPS ones

Rationale:
Reduces attack surface on kernel devs opening the links for MITM
as HTTPS traffic is much harder to manipulate.

Deterministic algorithm:
For each file:
If not .svg:
For each line:
If doesn't contain `\bxmlns\b`:
For each link, `\bhttp://[^# \t\r\n]*(?:\w|/)`:
If neither `\bgnu\.org/license`, nor `\bmozilla\.org/MPL\b`:
If both the HTTP and HTTPS versions
return 200 OK and serve the same content:
Replace HTTP with HTTPS.

Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

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