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Diffstat (limited to 'arch/x86/kernel/cpu/intel.c')
-rw-r--r--arch/x86/kernel/cpu/intel.c47
1 files changed, 32 insertions, 15 deletions
diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c
index 50163fa9034f..98a13db5f4be 100644
--- a/arch/x86/kernel/cpu/intel.c
+++ b/arch/x86/kernel/cpu/intel.c
@@ -371,6 +371,36 @@ static void detect_vmx_virtcap(struct cpuinfo_x86 *c)
}
}
+static void init_intel_energy_perf(struct cpuinfo_x86 *c)
+{
+ u64 epb;
+
+ /*
+ * Initialize MSR_IA32_ENERGY_PERF_BIAS if not already initialized.
+ * (x86_energy_perf_policy(8) is available to change it at run-time.)
+ */
+ if (!cpu_has(c, X86_FEATURE_EPB))
+ return;
+
+ rdmsrl(MSR_IA32_ENERGY_PERF_BIAS, epb);
+ if ((epb & 0xF) != ENERGY_PERF_BIAS_PERFORMANCE)
+ return;
+
+ pr_warn_once("ENERGY_PERF_BIAS: Set to 'normal', was 'performance'\n");
+ pr_warn_once("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);
+}
+
+static void intel_bsp_resume(struct cpuinfo_x86 *c)
+{
+ /*
+ * MSR_IA32_ENERGY_PERF_BIAS is lost across suspend/resume,
+ * so reinitialize it properly like during bootup:
+ */
+ init_intel_energy_perf(c);
+}
+
static void init_intel(struct cpuinfo_x86 *c)
{
unsigned int l2 = 0;
@@ -478,21 +508,7 @@ static void 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) {
- pr_warn_once("ENERGY_PERF_BIAS: Set to 'normal', was 'performance'\n");
- pr_warn_once("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);
- }
- }
+ init_intel_energy_perf(c);
}
#ifdef CONFIG_X86_32
@@ -747,6 +763,7 @@ static const struct cpu_dev intel_cpu_dev = {
.c_detect_tlb = intel_detect_tlb,
.c_early_init = early_init_intel,
.c_init = init_intel,
+ .c_bsp_resume = intel_bsp_resume,
.c_x86_vendor = X86_VENDOR_INTEL,
};