[PATCH 6.7 333/713] ACPI: CPPC: enable AMD CPPC V2 support for family 17h processors

Sasha Levin
2024-03-24T22:52:49Z

From: Perry Yuan <perry.yuan@amd.com>

[ Upstream commit a51ab63b297ce9e26e3ffb9be896018a42d5f32f ]

As there are some AMD processors which only support CPPC V2 firmware and
BIOS implementation, the amd_pstate driver will be failed to load when
system booting with below kernel warning message:

[ 0.477523] amd_pstate: the _CPC object is not present in SBIOS or ACPI disabled

To make the amd_pstate driver can be loaded on those TR40 processors, it
needs to match x86_model from 0x30 to 0x7F for family 17H.
With the change, the system can load amd_pstate driver as expected.

Reviewed-by: Mario Limonciello <mario.limonciello@amd.com>
Reported-by: Gino Badouri <badouri.g@gmail.com>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218171
Fixes: fbd74d1689 ("ACPI: CPPC: Fix enabling CPPC on AMD systems with shared memory")
Signed-off-by: Perry Yuan <perry.yuan@amd.com>
Reviewed-by: Gautham R. Shenoy <gautham.shenoy@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
arch/x86/kernel/acpi/cppc.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kernel/acpi/cppc.c b/arch/x86/kernel/acpi/cppc.c
index 8d8752b44f113..ff8f25faca3dd 100644
--- a/arch/x86/kernel/acpi/cppc.c
+++ b/arch/x86/kernel/acpi/cppc.c
@@ -20,7 +20,7 @@ bool cpc_supported_by_cpu(void)
(boot_cpu_data.x86_model >= 0x20 && boot_cpu_data.x86_model <= 0x2f)))
return true;
else if (boot_cpu_data.x86 == 0x17 &&
- boot_cpu_data.x86_model >= 0x70 && boot_cpu_data.x86_model <= 0x7f)
+ boot_cpu_data.x86_model >= 0x30 && boot_cpu_data.x86_model <= 0x7f)
return true;
return boot_cpu_has(X86_FEATURE_CPPC);
}
--
2.43.0