1 files changed, 54 insertions, 36 deletions

diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c
index c788abf1c457..099967302bf2 100644
--- a/drivers/cpufreq/intel_pstate.c
+++ b/drivers/cpufreq/intel_pstate.c
@@ -34,12 +34,15 @@
 
 #define SAMPLE_COUNT            3
 
-#define BYT_RATIOS      0x66a
-#define BYT_VIDS        0x66b
+#define BYT_RATIOS              0x66a
+#define BYT_VIDS                0x66b
+#define BYT_TURBO_RATIOS        0x66c
 
-#define FRAC_BITS 8
+
+#define FRAC_BITS 6
 #define int_tofp(X) ((int64_t)(X) << FRAC_BITS)
 #define fp_toint(X) ((X) >> FRAC_BITS)
+#define FP_ROUNDUP(X) ((X) += 1 << FRAC_BITS)
 
 static inline int32_t mul_fp(int32_t x, int32_t y)
 {
@@ -96,8 +99,7 @@ struct cpudata {
         u64     prev_aperf;
         u64     prev_mperf;
         unsigned long long prev_tsc;
-        int     sample_ptr;
-        struct sample samples[SAMPLE_COUNT];
+        struct sample sample;
 };
 
 static struct cpudata **all_cpu_data;
@@ -151,7 +153,7 @@ static inline void pid_reset(struct _pid *pid, int setpoint, int busy,
         pid->setpoint = setpoint;
         pid->deadband  = deadband;
         pid->integral  = int_tofp(integral);
-        pid->last_err  = setpoint - busy;
+        pid->last_err  = int_tofp(setpoint) - int_tofp(busy);
 }
 
 static inline void pid_p_gain_set(struct _pid *pid, int percent)
@@ -357,7 +359,7 @@ static int byt_get_min_pstate(void)
 {
         u64 value;
         rdmsrl(BYT_RATIOS, value);
-        return value & 0xFF;
+        return (value >> 8) & 0xFF;
 }
 
 static int byt_get_max_pstate(void)
@@ -367,6 +369,13 @@ static int byt_get_max_pstate(void)
         return (value >> 16) & 0xFF;
 }
 
+static int byt_get_turbo_pstate(void)
+{
+        u64 value;
+        rdmsrl(BYT_TURBO_RATIOS, value);
+        return value & 0x3F;
+}
+
 static void byt_set_pstate(struct cpudata *cpudata, int pstate)
 {
         u64 val;
@@ -437,7 +446,7 @@ static void core_set_pstate(struct cpudata *cpudata, int pstate)
         if (limits.no_turbo)
                 val |= (u64)1 << 32;
 
-        wrmsrl(MSR_IA32_PERF_CTL, val);
+        wrmsrl_on_cpu(cpudata->cpu, MSR_IA32_PERF_CTL, val);
 }
 
 static struct cpu_defaults core_params = {
@@ -469,7 +478,7 @@ static struct cpu_defaults byt_params = {
         .funcs = {
                 .get_max = byt_get_max_pstate,
                 .get_min = byt_get_min_pstate,
-                .get_turbo = byt_get_max_pstate,
+                .get_turbo = byt_get_turbo_pstate,
                 .set = byt_set_pstate,
                 .get_vid = byt_get_vid,
         },
@@ -547,18 +556,20 @@ static void intel_pstate_get_cpu_pstates(struct cpudata *cpu)
 static inline void intel_pstate_calc_busy(struct cpudata *cpu,
                                         struct sample *sample)
 {
-        u64 core_pct;
-        u64 c0_pct;
+        int32_t core_pct;
+        int32_t c0_pct;
+
+        core_pct = div_fp(int_tofp((sample->aperf)),
+                        int_tofp((sample->mperf)));
+        core_pct = mul_fp(core_pct, int_tofp(100));
+        FP_ROUNDUP(core_pct);
 
-        core_pct = div64_u64(sample->aperf * 100, sample->mperf);
+        c0_pct = div_fp(int_tofp(sample->mperf), int_tofp(sample->tsc));
 
-        c0_pct = div64_u64(sample->mperf * 100, sample->tsc);
         sample->freq = fp_toint(
-                mul_fp(int_tofp(cpu->pstate.max_pstate),
-                        int_tofp(core_pct * 1000)));
+                mul_fp(int_tofp(cpu->pstate.max_pstate * 1000), core_pct));
 
-        sample->core_pct_busy = mul_fp(int_tofp(core_pct),
-                                div_fp(int_tofp(c0_pct + 1), int_tofp(100)));
+        sample->core_pct_busy = mul_fp(core_pct, c0_pct);
 }
 
 static inline void intel_pstate_sample(struct cpudata *cpu)
@@ -570,15 +581,18 @@ static inline void intel_pstate_sample(struct cpudata *cpu)
         rdmsrl(MSR_IA32_MPERF, mperf);
         tsc = native_read_tsc();
 
-        cpu->sample_ptr = (cpu->sample_ptr + 1) % SAMPLE_COUNT;
-        cpu->samples[cpu->sample_ptr].aperf = aperf;
-        cpu->samples[cpu->sample_ptr].mperf = mperf;
-        cpu->samples[cpu->sample_ptr].tsc = tsc;
-        cpu->samples[cpu->sample_ptr].aperf -= cpu->prev_aperf;
-        cpu->samples[cpu->sample_ptr].mperf -= cpu->prev_mperf;
-        cpu->samples[cpu->sample_ptr].tsc -= cpu->prev_tsc;
+        aperf = aperf >> FRAC_BITS;
+        mperf = mperf >> FRAC_BITS;
+        tsc = tsc >> FRAC_BITS;
+
+        cpu->sample.aperf = aperf;
+        cpu->sample.mperf = mperf;
+        cpu->sample.tsc = tsc;
+        cpu->sample.aperf -= cpu->prev_aperf;
+        cpu->sample.mperf -= cpu->prev_mperf;
+        cpu->sample.tsc -= cpu->prev_tsc;
 
-        intel_pstate_calc_busy(cpu, &cpu->samples[cpu->sample_ptr]);
+        intel_pstate_calc_busy(cpu, &cpu->sample);
 
         cpu->prev_aperf = aperf;
         cpu->prev_mperf = mperf;
@@ -598,10 +612,11 @@ static inline int32_t intel_pstate_get_scaled_busy(struct cpudata *cpu)
 {
         int32_t core_busy, max_pstate, current_pstate;
 
-        core_busy = cpu->samples[cpu->sample_ptr].core_pct_busy;
+        core_busy = cpu->sample.core_pct_busy;
         max_pstate = int_tofp(cpu->pstate.max_pstate);
         current_pstate = int_tofp(cpu->pstate.current_pstate);
-        return mul_fp(core_busy, div_fp(max_pstate, current_pstate));
+        core_busy = mul_fp(core_busy, div_fp(max_pstate, current_pstate));
+        return FP_ROUNDUP(core_busy);
 }
 
 static inline void intel_pstate_adjust_busy_pstate(struct cpudata *cpu)
@@ -631,7 +646,7 @@ static void intel_pstate_timer_func(unsigned long __data)
 
         intel_pstate_sample(cpu);
 
-        sample = &cpu->samples[cpu->sample_ptr];
+        sample = &cpu->sample;
 
         intel_pstate_adjust_busy_pstate(cpu);
 
@@ -712,7 +727,7 @@ static unsigned int intel_pstate_get(unsigned int cpu_num)
         cpu = all_cpu_data[cpu_num];
         if (!cpu)
                 return 0;
-        sample = &cpu->samples[cpu->sample_ptr];
+        sample = &cpu->sample;
         return sample->freq;
 }
 
@@ -756,14 +771,17 @@ static int intel_pstate_verify_policy(struct cpufreq_policy *policy)
         return 0;
 }
 
-static int intel_pstate_cpu_exit(struct cpufreq_policy *policy)
+static void intel_pstate_stop_cpu(struct cpufreq_policy *policy)
 {
-        int cpu = policy->cpu;
+        int cpu_num = policy->cpu;
+        struct cpudata *cpu = all_cpu_data[cpu_num];
 
-        del_timer(&all_cpu_data[cpu]->timer);
-        kfree(all_cpu_data[cpu]);
-        all_cpu_data[cpu] = NULL;
-        return 0;
+        pr_info("intel_pstate CPU %d exiting\n", cpu_num);
+
+        del_timer_sync(&all_cpu_data[cpu_num]->timer);
+        intel_pstate_set_pstate(cpu, cpu->pstate.min_pstate);
+        kfree(all_cpu_data[cpu_num]);
+        all_cpu_data[cpu_num] = NULL;
 }
 
 static int intel_pstate_cpu_init(struct cpufreq_policy *policy)
@@ -801,7 +819,7 @@ static struct cpufreq_driver intel_pstate_driver = {
         .setpolicy      = intel_pstate_set_policy,
         .get            = intel_pstate_get,
         .init           = intel_pstate_cpu_init,
-        .exit           = intel_pstate_cpu_exit,
+        .stop_cpu       = intel_pstate_stop_cpu,
         .name           = "intel_pstate",
 };