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-rw-r--r--arch/x86/kernel/cpu/intel.c10
1 files changed, 6 insertions, 4 deletions
diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c
index 2181304dc7d3..4cbb2e69bea1 100644
--- a/arch/x86/kernel/cpu/intel.c
+++ b/arch/x86/kernel/cpu/intel.c
@@ -201,10 +201,6 @@ static void early_init_intel(struct cpuinfo_x86 *c)
{
u64 misc_enable;
- if ((c->x86 == 0xf && c->x86_model >= 0x03) ||
- (c->x86 == 0x6 && c->x86_model >= 0x0e))
- set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
-
if (c->x86 >= 6 && !cpu_has(c, X86_FEATURE_IA64))
c->microcode = intel_get_microcode_revision();
@@ -257,10 +253,16 @@ static void early_init_intel(struct cpuinfo_x86 *c)
*
* It is also reliable across cores and sockets. (but not across
* cabinets - we turn it off in that case explicitly.)
+ *
+ * Use a model-specific check for some older CPUs that have invariant
+ * TSC but may not report it architecturally via 8000_0007.
*/
if (c->x86_power & (1 << 8)) {
set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
set_cpu_cap(c, X86_FEATURE_NONSTOP_TSC);
+ } else if ((c->x86_vfm >= INTEL_P4_PRESCOTT && c->x86_vfm <= INTEL_P4_WILLAMETTE) ||
+ (c->x86_vfm >= INTEL_CORE_YONAH && c->x86_vfm <= INTEL_IVYBRIDGE)) {
+ set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
}
/* Penwell and Cloverview have the TSC which doesn't sleep on S3 */