diff options
Diffstat (limited to 'arch/x86/kernel/cpu/intel.c')
| -rw-r--r-- | arch/x86/kernel/cpu/intel.c | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c index 24ff26a38ad..7aeef1d327b 100644 --- a/arch/x86/kernel/cpu/intel.c +++ b/arch/x86/kernel/cpu/intel.c @@ -24,7 +24,6 @@ #ifdef CONFIG_X86_LOCAL_APIC #include <asm/mpspec.h> #include <asm/apic.h> -#include <mach_apic.h> #endif static void __cpuinit early_init_intel(struct cpuinfo_x86 *c) @@ -63,6 +62,18 @@ static void __cpuinit early_init_intel(struct cpuinfo_x86 *c) set_cpu_cap(c, X86_FEATURE_NONSTOP_TSC); } + /* + * There is a known erratum on Pentium III and Core Solo + * and Core Duo CPUs. + * " Page with PAT set to WC while associated MTRR is UC + * may consolidate to UC " + * Because of this erratum, it is better to stick with + * setting WC in MTRR rather than using PAT on these CPUs. + * + * Enable PAT WC only on P4, Core 2 or later CPUs. + */ + if (c->x86 == 6 && c->x86_model < 15) + clear_cpu_cap(c, X86_FEATURE_PAT); } #ifdef CONFIG_X86_32 |