<feed xmlns='http://www.w3.org/2005/Atom'>
<title>kernel.git/arch/x86/kernel/acpi/cppc.c, branch linux-5.18.y</title>
<subtitle>Hosts the 0x221E linux distro kernel.
</subtitle>
<id>https://git.0xinfinity.dev/distro/kernel.git/atom?h=linux-5.18.y</id>
<link rel='self' href='https://git.0xinfinity.dev/distro/kernel.git/atom?h=linux-5.18.y'/>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/'/>
<updated>2022-07-22T08:21:57Z</updated>
<entry>
<title>ACPI: CPPC: Fix enabling CPPC on AMD systems with shared memory</title>
<updated>2022-07-22T08:21:57Z</updated>
<author>
<name>Mario Limonciello</name>
</author>
<published>2022-07-13T17:53:46Z</published>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/commit/?id=89c3c9dd7e0331d4e2529e91f273bc31e3c04f33'/>
<id>urn:sha1:89c3c9dd7e0331d4e2529e91f273bc31e3c04f33</id>
<content type='text'>
commit fbd74d16890b9f5d08ea69b5282b123c894f8860 upstream.

When commit 72f2ecb7ece7 ("ACPI: bus: Set CPPC _OSC bits for all
and when CPPC_LIB is supported") was introduced, we found collateral
damage that a number of AMD systems that supported CPPC but
didn't advertise support in _OSC stopped having a functional
amd-pstate driver. The _OSC was only enforced on Intel systems at that
time.

This was fixed for the MSR based designs by commit 8b356e536e69f
("ACPI: CPPC: Don't require _OSC if X86_FEATURE_CPPC is supported")
but some shared memory based designs also support CPPC but haven't
advertised support in the _OSC.  Add support for those designs as well by
hardcoding the list of systems.

Fixes: 72f2ecb7ece7 ("ACPI: bus: Set CPPC _OSC bits for all and when CPPC_LIB is supported")
Fixes: 8b356e536e69f ("ACPI: CPPC: Don't require _OSC if X86_FEATURE_CPPC is supported")
Link: https://lore.kernel.org/all/3559249.JlDtxWtqDm@natalenko.name/
Cc: 5.18+ &lt;stable@vger.kernel.org&gt; # 5.18+
Reported-and-tested-by: Oleksandr Natalenko &lt;oleksandr@natalenko.name&gt;
Signed-off-by: Mario Limonciello &lt;mario.limonciello@amd.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>ACPI: CPPC: Don't require _OSC if X86_FEATURE_CPPC is supported</title>
<updated>2022-07-12T14:42:23Z</updated>
<author>
<name>Mario Limonciello</name>
</author>
<published>2022-07-05T18:29:15Z</published>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/commit/?id=2783414e6ef725bac946dc5d4d9288e34b6f5a13'/>
<id>urn:sha1:2783414e6ef725bac946dc5d4d9288e34b6f5a13</id>
<content type='text'>
[ Upstream commit 8b356e536e69f3a4d6778ae9f0858a1beadabb1f ]

commit 72f2ecb7ece7 ("ACPI: bus: Set CPPC _OSC bits for all and
when CPPC_LIB is supported") added support for claiming to
support CPPC in _OSC on non-Intel platforms.

This unfortunately caused a regression on a vartiety of AMD
platforms in the field because a number of AMD platforms don't set
the `_OSC` bit 5 or 6 to indicate CPPC or CPPC v2 support.

As these AMD platforms already claim CPPC support via a dedicated
MSR from `X86_FEATURE_CPPC`, use this enable this feature rather
than requiring the `_OSC` on platforms with a dedicated MSR.

If there is additional breakage on the shared memory designs also
missing this _OSC, additional follow up changes may be needed.

Fixes: 72f2ecb7ece7 ("Set CPPC _OSC bits for all and when CPPC_LIB is supported")
Reported-by: Perry Yuan &lt;perry.yuan@amd.com&gt;
Signed-off-by: Mario Limonciello &lt;mario.limonciello@amd.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>
</entry>
<entry>
<title>x86/ACPI: CPPC: Move init_freq_invariance_cppc() into x86 CPPC</title>
<updated>2022-03-08T18:16:43Z</updated>
<author>
<name>Huang Rui</name>
</author>
<published>2022-02-14T10:14:50Z</published>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/commit/?id=eb5616d4adeebf958a42822ee440d79e9f803bf7'/>
<id>urn:sha1:eb5616d4adeebf958a42822ee440d79e9f803bf7</id>
<content type='text'>
The init_freq_invariance_cppc code actually doesn't need the SMP
functionality. So setting the CONFIG_SMP as the check condition for
init_freq_invariance_cppc may cause the confusion to misunderstand the
CPPC. And the x86 CPPC file is better space to store the CPPC related
functions, while the init_freq_invariance_cppc is out of smpboot, that
means, the CONFIG_SMP won't be mandatory condition any more. And It's more
clear than before.

Signed-off-by: Huang Rui &lt;ray.huang@amd.com&gt;
[ rjw: Subject adjustment ]
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</content>
</entry>
<entry>
<title>x86/ACPI: CPPC: Move AMD maximum frequency ratio setting function into x86 CPPC</title>
<updated>2022-03-08T18:16:43Z</updated>
<author>
<name>Huang Rui</name>
</author>
<published>2022-02-14T10:14:48Z</published>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/commit/?id=82d89369141b8fab56deff540121b8d09d289bfd'/>
<id>urn:sha1:82d89369141b8fab56deff540121b8d09d289bfd</id>
<content type='text'>
The AMD maximum frequency ratio setting function depends on CPPC, so the
x86 CPPC implementation file is better space for this function.

Signed-off-by: Huang Rui &lt;ray.huang@amd.com&gt;
[ rjw: Subject adjustment ]
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</content>
</entry>
<entry>
<title>x86/ACPI: CPPC: Rename cppc_msr.c to cppc.c</title>
<updated>2022-03-08T18:16:43Z</updated>
<author>
<name>Huang Rui</name>
</author>
<published>2022-02-14T10:14:47Z</published>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/commit/?id=fd8af343a299df264c41b1219358f502c7b5b18a'/>
<id>urn:sha1:fd8af343a299df264c41b1219358f502c7b5b18a</id>
<content type='text'>
Rename the cppc_msr.c to cppc.c in x86 ACPI, that expects to use this file
to cover more function implementation for ACPI CPPC beside MSR helpers.
Naming as "cppc" is more straightforward as one of the functionalities
under ACPI subsystem.

Signed-off-by: Huang Rui &lt;ray.huang@amd.com&gt;
[ rjw: Subject ]
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</content>
</entry>
</feed>
