diff options
| author | Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> | 2009-04-06 18:51:29 -0700 |
|---|---|---|
| committer | Len Brown <len.brown@intel.com> | 2009-04-07 18:17:51 -0400 |
| commit | db954b5898dd3ef3ef93f4144158ea8f97deb058 (patch) | |
| tree | 781b62baa5aa262fca99198ba326e5e9cc44b26a /arch/x86/kernel/cpu | |
| parent | 577c9c456f0e1371cbade38eaf91ae8e8a308555 (diff) | |
x86 ACPI: Add support for Always Running APIC timer
Add support for Always Running APIC timer, CPUID_0x6_EAX_Bit2.
This bit means the APIC timer continues to run even when CPU is
in deep C-states.
The advantage is that we can use LAPIC timer on these CPUs
always, and there is no need for "slow to read and program"
external timers (HPET/PIT) and the timer broadcast logic
and related code in C-state entry and exit.
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Diffstat (limited to 'arch/x86/kernel/cpu')
| -rw-r--r-- | arch/x86/kernel/cpu/addon_cpuid_features.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/x86/kernel/cpu/addon_cpuid_features.c b/arch/x86/kernel/cpu/addon_cpuid_features.c index 8220ae69849..c965e521271 100644 --- a/arch/x86/kernel/cpu/addon_cpuid_features.c +++ b/arch/x86/kernel/cpu/addon_cpuid_features.c @@ -31,6 +31,7 @@ void __cpuinit init_scattered_cpuid_features(struct cpuinfo_x86 *c) static const struct cpuid_bit __cpuinitconst cpuid_bits[] = { { X86_FEATURE_IDA, CR_EAX, 1, 0x00000006 }, + { X86_FEATURE_ARAT, CR_EAX, 2, 0x00000006 }, { 0, 0, 0, 0 } }; |