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| author | Mario Limonciello <mario.limonciello@amd.com> | 2022-07-05 21:29:15 +0300 |
|---|---|---|
| committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2022-07-05 21:36:11 +0300 |
| commit | 8b356e536e69f3a4d6778ae9f0858a1beadabb1f (patch) | |
| tree | d94dad9bd21c339a808f95f19da24175ea79049b /arch | |
| parent | 7feec7430edddb87c24b0a86b08a03d0b496a755 (diff) | |
| download | linux-8b356e536e69f3a4d6778ae9f0858a1beadabb1f.tar.xz | |
ACPI: CPPC: Don't require _OSC if X86_FEATURE_CPPC is supported
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 <perry.yuan@amd.com>
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/kernel/acpi/cppc.c | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/arch/x86/kernel/acpi/cppc.c b/arch/x86/kernel/acpi/cppc.c index 8b8cbf22461a..734b96454896 100644 --- a/arch/x86/kernel/acpi/cppc.c +++ b/arch/x86/kernel/acpi/cppc.c @@ -11,6 +11,16 @@ /* Refer to drivers/acpi/cppc_acpi.c for the description of functions */ +bool cpc_supported_by_cpu(void) +{ + switch (boot_cpu_data.x86_vendor) { + case X86_VENDOR_AMD: + case X86_VENDOR_HYGON: + return boot_cpu_has(X86_FEATURE_CPPC); + } + return false; +} + bool cpc_ffh_supported(void) { return true; |