Merge branch 'driver-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git...

[pandora-kernel.git] / arch / x86 / kernel / cpu / intel.c

diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c
index 1edf5ba..ed6086e 100644 (file)
--- a/arch/x86/kernel/cpu/intel.c
+++ b/arch/x86/kernel/cpu/intel.c
@@ -456,6 +456,24 @@ static void __cpuinit init_intel(struct cpuinfo_x86 *c)
 
        if (cpu_has(c, X86_FEATURE_VMX))
                detect_vmx_virtcap(c);
+
+       /*
+        * Initialize MSR_IA32_ENERGY_PERF_BIAS if BIOS did not.
+        * x86_energy_perf_policy(8) is available to change it at run-time
+        */
+       if (cpu_has(c, X86_FEATURE_EPB)) {
+               u64 epb;
+
+               rdmsrl(MSR_IA32_ENERGY_PERF_BIAS, epb);
+               if ((epb & 0xF) == ENERGY_PERF_BIAS_PERFORMANCE) {
+                       printk_once(KERN_WARNING "ENERGY_PERF_BIAS:"
+                               " Set to 'normal', was 'performance'\n"
+                               "ENERGY_PERF_BIAS: View and update with"
+                               " x86_energy_perf_policy(8)\n");
+                       epb = (epb & ~0xF) | ENERGY_PERF_BIAS_NORMAL;
+                       wrmsrl(MSR_IA32_ENERGY_PERF_BIAS, epb);
+               }
+       }
 }
 
 #ifdef CONFIG_X86_32