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x86: Fix keeping track of AMD C1E

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Accomodate the original C1E-aware idle routine to the different times
during boot when the BIOS enables C1E. While at it, remove the synthetic
CPUID flag in favor of a single global setting which denotes C1E status
on the system.

[ hpa: changed c1e_enabled to be a bool; clarified cpu bit 3:21 comment ]

Signed-off-by: Michal Schmidt <mschmidt@redhat.com>
LKML-Reference: <20100727165335.GA11630@aftab>
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
This commit is contained in:
Michal Schmidt
2010-07-27 18:53:35 +02:00
committed by H. Peter Anvin
parent 9792db6174
commit e8c534ec06
5 changed files with 9 additions and 6 deletions
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8
arch/x86/kernel/process.c
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@ -525,8 +525,10 @@ static int __cpuinit mwait_usable(const struct cpuinfo_x86 *c)
return (edx & MWAIT_EDX_C1);
}
bool c1e_detected;
EXPORT_SYMBOL(c1e_detected);
static cpumask_var_t c1e_mask;
static int c1e_detected;
void c1e_remove_cpu(int cpu)
{
@ -548,12 +550,12 @@ static void c1e_idle(void)
u32 lo, hi;
rdmsr(MSR_K8_INT_PENDING_MSG, lo, hi);
if (lo & K8_INTP_C1E_ACTIVE_MASK) {
c1e_detected = 1;
c1e_detected = true;
if (!boot_cpu_has(X86_FEATURE_NONSTOP_TSC))
mark_tsc_unstable("TSC halt in AMD C1E");
printk(KERN_INFO "System has AMD C1E enabled\n");
set_cpu_cap(&boot_cpu_data, X86_FEATURE_AMDC1E);
}
}