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Diffstat (limited to 'arch/x86/kernel/cpu/intel.c')
-rw-r--r--arch/x86/kernel/cpu/intel.c24
1 files changed, 23 insertions, 1 deletions
diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c
index 8ea6929e974..5fff00c70de 100644
--- a/arch/x86/kernel/cpu/intel.c
+++ b/arch/x86/kernel/cpu/intel.c
@@ -4,6 +4,7 @@
#include <linux/string.h>
#include <linux/bitops.h>
#include <linux/smp.h>
+#include <linux/sched.h>
#include <linux/thread_info.h>
#include <linux/module.h>
@@ -29,6 +30,19 @@
static void __cpuinit early_init_intel(struct cpuinfo_x86 *c)
{
+ /* Unmask CPUID levels if masked: */
+ if (c->x86 > 6 || (c->x86 == 6 && c->x86_model >= 0xd)) {
+ u64 misc_enable;
+
+ rdmsrl(MSR_IA32_MISC_ENABLE, misc_enable);
+
+ if (misc_enable & MSR_IA32_MISC_ENABLE_LIMIT_CPUID) {
+ misc_enable &= ~MSR_IA32_MISC_ENABLE_LIMIT_CPUID;
+ wrmsrl(MSR_IA32_MISC_ENABLE, misc_enable);
+ c->cpuid_level = cpuid_eax(0);
+ }
+ }
+
if ((c->x86 == 0xf && c->x86_model >= 0x03) ||
(c->x86 == 0x6 && c->x86_model >= 0x0e))
set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
@@ -43,11 +57,16 @@ static void __cpuinit early_init_intel(struct cpuinfo_x86 *c)
/*
* c->x86_power is 8000_0007 edx. Bit 8 is TSC runs at constant rate
- * with P/T states and does not stop in deep C-states
+ * with P/T states and does not stop in deep C-states.
+ *
+ * It is also reliable across cores and sockets. (but not across
+ * cabinets - we turn it off in that case explicitly.)
*/
if (c->x86_power & (1 << 8)) {
set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
set_cpu_cap(c, X86_FEATURE_NONSTOP_TSC);
+ set_cpu_cap(c, X86_FEATURE_TSC_RELIABLE);
+ sched_clock_stable = 1;
}
}
@@ -278,6 +297,9 @@ static void __cpuinit init_intel(struct cpuinfo_x86 *c)
ds_init_intel(c);
}
+ if (c->x86 == 6 && c->x86_model == 29 && cpu_has_clflush)
+ set_cpu_cap(c, X86_FEATURE_CLFLUSH_MONITOR);
+
#ifdef CONFIG_X86_64
if (c->x86 == 15)
c->x86_cache_alignment = c->x86_clflush_size * 2;