]> git.baikalelectronics.ru Git - kernel.git/commit
ACPI: CPPC: Fix enabling CPPC on AMD systems with shared memory
authorMario Limonciello <mario.limonciello@amd.com>
Wed, 13 Jul 2022 17:53:46 +0000 (12:53 -0500)
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>
Wed, 13 Jul 2022 19:13:14 +0000 (21:13 +0200)
commitb8446391e7d19a254bbe4d55727ecd02d12e23c3
tree5a6cce37154fae274c1a7b04e15dfd3268058e0c
parent0c8b98e40f9d61a6792a879de085b19667a1f51b
ACPI: CPPC: Fix enabling CPPC on AMD systems with shared memory

When commit 67339319b1b6 ("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 f17f2c10da180
("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: 67339319b1b6 ("ACPI: bus: Set CPPC _OSC bits for all and when CPPC_LIB is supported")
Fixes: f17f2c10da180 ("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+ <stable@vger.kernel.org> # 5.18+
Reported-and-tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
arch/x86/kernel/acpi/cppc.c