diff options
| author | Perry Yuan <[email protected]> | 2024-05-25 23:08:43 +0800 |
|---|---|---|
| committer | Mario Limonciello <[email protected]> | 2024-06-11 16:12:12 -0500 |
| commit | c7107750b2ffaa4950faa53f84f9c9aa2caac89a (patch) | |
| tree | d861794d844e56f21afa415ef7edee3cf6066040 | |
| parent | 83a7eefedc9b56fe7bfeff13b6c7356688ffa670 (diff) | |
x86/cpufeatures: Add AMD FAST CPPC feature flag
Some AMD Zen 4 processors support a new feature FAST CPPC which
allows for a faster CPPC loop due to internal architectural
enhancements. The goal of this faster loop is higher performance
at the same power consumption.
Reference:
See the page 99 of PPR for AMD Family 19h Model 61h rev.B1, docID 56713
Signed-off-by: Perry Yuan <[email protected]>
Signed-off-by: Xiaojian Du <[email protected]>
Reviewed-by: Borislav Petkov (AMD) <[email protected]>
| -rw-r--r-- | arch/x86/include/asm/cpufeatures.h | 1 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/scattered.c | 1 |
2 files changed, 2 insertions, 0 deletions
diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h index 3c7434329661..6c128d463a14 100644 --- a/arch/x86/include/asm/cpufeatures.h +++ b/arch/x86/include/asm/cpufeatures.h @@ -470,6 +470,7 @@ #define X86_FEATURE_BHI_CTRL (21*32+ 2) /* "" BHI_DIS_S HW control available */ #define X86_FEATURE_CLEAR_BHB_HW (21*32+ 3) /* "" BHI_DIS_S HW control enabled */ #define X86_FEATURE_CLEAR_BHB_LOOP_ON_VMEXIT (21*32+ 4) /* "" Clear branch history at vmexit using SW loop */ +#define X86_FEATURE_FAST_CPPC (21*32 + 5) /* "" AMD Fast CPPC */ /* * BUG word(s) diff --git a/arch/x86/kernel/cpu/scattered.c b/arch/x86/kernel/cpu/scattered.c index af5aa2c754c2..c84c30188fdf 100644 --- a/arch/x86/kernel/cpu/scattered.c +++ b/arch/x86/kernel/cpu/scattered.c @@ -45,6 +45,7 @@ static const struct cpuid_bit cpuid_bits[] = { { X86_FEATURE_HW_PSTATE, CPUID_EDX, 7, 0x80000007, 0 }, { X86_FEATURE_CPB, CPUID_EDX, 9, 0x80000007, 0 }, { X86_FEATURE_PROC_FEEDBACK, CPUID_EDX, 11, 0x80000007, 0 }, + { X86_FEATURE_FAST_CPPC, CPUID_EDX, 15, 0x80000007, 0 }, { X86_FEATURE_MBA, CPUID_EBX, 6, 0x80000008, 0 }, { X86_FEATURE_SMBA, CPUID_EBX, 2, 0x80000020, 0 }, { X86_FEATURE_BMEC, CPUID_EBX, 3, 0x80000020, 0 }, |