x86, cpu init: call early_init_xxx in init_xxx
so we:
1. could set some cap to ap
2. restore some cap after memset in identify_cpu for boot cpu
esp for CONSTANT_TSC this matters, as:
before this patch:
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt pdpe1gb rdtscp lm 3dnowext 3dnow rep_good nopl pni monitor cx16 lahf_lm cmp_legacy svm extapic cr8_legacy abm sse4a misalignsse 3dnowprefetch osvw ibs
after this patch:
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt pdpe1gb rdtscp lm 3dnowext 3dnow constant_tsc rep_good nopl pni monitor cx16 lahf_lm cmp_legacy svm extapic cr8_legacy abm sse4a misalignsse 3dnowprefetch osvw ibs
so constant_tsc is back...
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index e0ba2c7..c3175da 100644
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -26,11 +26,8 @@
static void __cpuinit early_init_amd(struct cpuinfo_x86 *c)
{
- if (cpuid_eax(0x80000000) >= 0x80000007) {
- c->x86_power = cpuid_edx(0x80000007);
- if (c->x86_power & (1<<8))
- set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
- }
+ if (c->x86_power & (1<<8))
+ set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
/* Set MTRR capability flag if appropriate */
if (c->x86_model == 13 || c->x86_model == 9 ||
