1 files changed, 31 insertions, 14 deletions

diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c
index 872c5772c5d3..c5b81beccc8e 100644
--- a/drivers/cpufreq/intel_pstate.c
+++ b/drivers/cpufreq/intel_pstate.c
@@ -614,6 +614,19 @@ static void core_set_pstate(struct cpudata *cpudata, int pstate)
         wrmsrl_on_cpu(cpudata->cpu, MSR_IA32_PERF_CTL, val);
 }
 
+static int knl_get_turbo_pstate(void)
+{
+        u64 value;
+        int nont, ret;
+
+        rdmsrl(MSR_NHM_TURBO_RATIO_LIMIT, value);
+        nont = core_get_max_pstate();
+        ret = (((value) >> 8) & 0xFF);
+        if (ret <= nont)
+                ret = nont;
+        return ret;
+}
+
 static struct cpu_defaults core_params = {
         .pid_policy = {
                 .sample_rate_ms = 10,
@@ -651,6 +664,23 @@ static struct cpu_defaults byt_params = {
         },
 };
 
+static struct cpu_defaults knl_params = {
+        .pid_policy = {
+                .sample_rate_ms = 10,
+                .deadband = 0,
+                .setpoint = 97,
+                .p_gain_pct = 20,
+                .d_gain_pct = 0,
+                .i_gain_pct = 0,
+        },
+        .funcs = {
+                .get_max = core_get_max_pstate,
+                .get_min = core_get_min_pstate,
+                .get_turbo = knl_get_turbo_pstate,
+                .set = core_set_pstate,
+        },
+};
+
 static void intel_pstate_get_min_max(struct cpudata *cpu, int *min, int *max)
 {
         int max_perf = cpu->pstate.turbo_pstate;
@@ -865,6 +895,7 @@ static const struct x86_cpu_id intel_pstate_cpu_ids[] = {
         ICPU(0x4e, core_params),
         ICPU(0x4f, core_params),
         ICPU(0x56, core_params),
+        ICPU(0x57, knl_params),
         {}
 };
 MODULE_DEVICE_TABLE(x86cpu, intel_pstate_cpu_ids);
@@ -1024,25 +1055,11 @@ static unsigned int force_load;
 
 static int intel_pstate_msrs_not_valid(void)
 {
-        /* Check that all the msr's we are using are valid. */
-        u64 aperf, mperf, tmp;
-
-        rdmsrl(MSR_IA32_APERF, aperf);
-        rdmsrl(MSR_IA32_MPERF, mperf);
-
         if (!pstate_funcs.get_max() ||
             !pstate_funcs.get_min() ||
             !pstate_funcs.get_turbo())
                 return -ENODEV;
 
-        rdmsrl(MSR_IA32_APERF, tmp);
-        if (!(tmp - aperf))
-                return -ENODEV;
-
-        rdmsrl(MSR_IA32_MPERF, tmp);
-        if (!(tmp - mperf))
-                return -ENODEV;
-
         return 0;
 }