diff options
| author | Venkatesh Pallipadi <venki@google.com> | 2010-06-03 23:22:28 -0400 |
|---|---|---|
| committer | H. Peter Anvin <hpa@linux.intel.com> | 2010-06-16 13:37:32 -0700 |
| commit | 23016bf0d25d62c45d8b8f61d55b290d704f7a79 (patch) | |
| tree | 71229d01b759c29ee2b13645d530aea81d557b94 /arch/x86/include/asm/cpufeature.h | |
| parent | 12d8a961289644d265d8b3e88201878837c3b814 (diff) | |
x86: Look for IA32_ENERGY_PERF_BIAS support
The new IA32_ENERGY_PERF_BIAS MSR allows system software to give
hardware a hint whether OS policy favors more power saving,
or more performance. This allows the OS to have some influence
on internal hardware power/performance tradeoffs where the OS
has previously had no influence.
The support for this feature is indicated by CPUID.06H.ECX.bit3,
as documented in the Intel Architectures Software Developer's Manual.
This patch discovers support of this feature and displays it
as "epb" in /proc/cpuinfo.
Signed-off-by: Venkatesh Pallipadi <venki@google.com>
LKML-Reference: <alpine.LFD.2.00.1006032310160.6669@localhost.localdomain>
Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Diffstat (limited to 'arch/x86/include/asm/cpufeature.h')
| -rw-r--r-- | arch/x86/include/asm/cpufeature.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/x86/include/asm/cpufeature.h b/arch/x86/include/asm/cpufeature.h index 468145914389..2a904f4071fe 100644 --- a/arch/x86/include/asm/cpufeature.h +++ b/arch/x86/include/asm/cpufeature.h @@ -162,6 +162,7 @@ #define X86_FEATURE_IDA (7*32+ 0) /* Intel Dynamic Acceleration */ #define X86_FEATURE_ARAT (7*32+ 1) /* Always Running APIC Timer */ #define X86_FEATURE_CPB (7*32+ 2) /* AMD Core Performance Boost */ +#define X86_FEATURE_EPB (7*32+ 3) /* IA32_ENERGY_PERF_BIAS support */ /* Virtualization flags: Linux defined */ #define X86_FEATURE_TPR_SHADOW (8*32+ 0) /* Intel TPR Shadow */ |