Merge tag 'devicetree-fixes-for-5.13-2' of git://git.kernel.org/pub/scm/linux/kernel...

[linux-2.6-microblaze.git] / drivers / cpufreq / intel_pstate.c

diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c
index f040106..0e69dff 100644 (file)
--- a/drivers/cpufreq/intel_pstate.c
+++ b/drivers/cpufreq/intel_pstate.c
@@ -3033,6 +3033,14 @@ static const struct x86_cpu_id hwp_support_ids[] __initconst = {
        {}
 };
 
+static bool intel_pstate_hwp_is_enabled(void)
+{
+       u64 value;
+
+       rdmsrl(MSR_PM_ENABLE, value);
+       return !!(value & 0x1);
+}
+
 static int __init intel_pstate_init(void)
 {
        const struct x86_cpu_id *id;
@@ -3051,8 +3059,12 @@ static int __init intel_pstate_init(void)
                 * Avoid enabling HWP for processors without EPP support,
                 * because that means incomplete HWP implementation which is a
                 * corner case and supporting it is generally problematic.
+                *
+                * If HWP is enabled already, though, there is no choice but to
+                * deal with it.
                 */
-               if (!no_hwp && boot_cpu_has(X86_FEATURE_HWP_EPP)) {
+               if ((!no_hwp && boot_cpu_has(X86_FEATURE_HWP_EPP)) ||
+                   intel_pstate_hwp_is_enabled()) {
                        hwp_active++;
                        hwp_mode_bdw = id->driver_data;
                        intel_pstate.attr = hwp_cpufreq_attrs;