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cpufreq: intel_pstate: Check cpuid for MSR_HWP_INTERRUPT

The MSR MSR_HWP_INTERRUPT is valid only when CPUID.06H:EAX[8] = 1, so
check for feature before accessing this MSR.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Srinivas Pandruvada 9 years ago
parent
commit
da7de91c3e
1 changed files with 2 additions and 1 deletions
  1. 2 1
      drivers/cpufreq/intel_pstate.c

+ 2 - 1
drivers/cpufreq/intel_pstate.c

@@ -806,7 +806,8 @@ static void __init intel_pstate_sysfs_expose_params(void)
 static void intel_pstate_hwp_enable(struct cpudata *cpudata)
 {
 	/* First disable HWP notification interrupt as we don't process them */
-	wrmsrl_on_cpu(cpudata->cpu, MSR_HWP_INTERRUPT, 0x00);
+	if (static_cpu_has(X86_FEATURE_HWP_NOTIFY))
+		wrmsrl_on_cpu(cpudata->cpu, MSR_HWP_INTERRUPT, 0x00);
 
 	wrmsrl_on_cpu(cpudata->cpu, MSR_PM_ENABLE, 0x1);
 }