1 files changed, 47 insertions, 38 deletions

diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c
index bfe4280399bc..aebd4572eb6d 100644
--- a/drivers/cpufreq/intel_pstate.c
+++ b/drivers/cpufreq/intel_pstate.c
@@ -35,12 +35,13 @@
 #define BYT_RATIOS		0x66a
 #define BYT_VIDS		0x66b
 #define BYT_TURBO_RATIOS	0x66c
+#define BYT_TURBO_VIDS		0x66d
 
 
-#define FRAC_BITS 6
+#define FRAC_BITS 8
 #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)
 {
@@ -56,8 +57,8 @@ struct sample {
 	int32_t core_pct_busy;
 	u64 aperf;
 	u64 mperf;
-	unsigned long long tsc;
 	int freq;
+	ktime_t time;
 };
 
 struct pstate_data {
@@ -68,8 +69,9 @@ struct pstate_data {
 };
 
 struct vid_data {
-	int32_t min;
-	int32_t max;
+	int min;
+	int max;
+	int turbo;
 	int32_t ratio;
 };
 
@@ -92,9 +94,9 @@ struct cpudata {
 	struct vid_data vid;
 	struct _pid pid;
 
+	ktime_t last_sample_time;
 	u64	prev_aperf;
 	u64	prev_mperf;
-	unsigned long long prev_tsc;
 	struct sample sample;
 };
 
@@ -194,7 +196,10 @@ static signed int pid_calc(struct _pid *pid, int32_t busy)
 	pid->last_err = fp_error;
 
 	result = pterm + mul_fp(pid->integral, pid->i_gain) + dterm;
-
+	if (result >= 0)
+		result = result + (1 << (FRAC_BITS-1));
+	else
+		result = result - (1 << (FRAC_BITS-1));
 	return (signed int)fp_toint(result);
 }
 
@@ -355,14 +360,14 @@ static int byt_get_min_pstate(void)
 {
 	u64 value;
 	rdmsrl(BYT_RATIOS, value);
-	return (value >> 8) & 0xFF;
+	return (value >> 8) & 0x3F;
 }
 
 static int byt_get_max_pstate(void)
 {
 	u64 value;
 	rdmsrl(BYT_RATIOS, value);
-	return (value >> 16) & 0xFF;
+	return (value >> 16) & 0x3F;
 }
 
 static int byt_get_turbo_pstate(void)
@@ -389,6 +394,9 @@ static void byt_set_pstate(struct cpudata *cpudata, int pstate)
 	vid_fp = clamp_t(int32_t, vid_fp, cpudata->vid.min, cpudata->vid.max);
 	vid = fp_toint(vid_fp);
 
+	if (pstate > cpudata->pstate.max_pstate)
+		vid = cpudata->vid.turbo;
+
 	val |= vid;
 
 	wrmsrl(MSR_IA32_PERF_CTL, val);
@@ -398,13 +406,17 @@ static void byt_get_vid(struct cpudata *cpudata)
 {
 	u64 value;
 
+
 	rdmsrl(BYT_VIDS, value);
-	cpudata->vid.min = int_tofp((value >> 8) & 0x7f);
-	cpudata->vid.max = int_tofp((value >> 16) & 0x7f);
+	cpudata->vid.min = int_tofp((value >> 8) & 0x3f);
+	cpudata->vid.max = int_tofp((value >> 16) & 0x3f);
 	cpudata->vid.ratio = div_fp(
 		cpudata->vid.max - cpudata->vid.min,
 		int_tofp(cpudata->pstate.max_pstate -
 			cpudata->pstate.min_pstate));
+
+	rdmsrl(BYT_TURBO_VIDS, value);
+	cpudata->vid.turbo = value & 0x7f;
 }
 
 
@@ -539,57 +551,48 @@ static void intel_pstate_get_cpu_pstates(struct cpudata *cpu)
 
 	if (pstate_funcs.get_vid)
 		pstate_funcs.get_vid(cpu);
-
-	/*
-	 * goto max pstate so we don't slow up boot if we are built-in if we are
-	 * a module we will take care of it during normal operation
-	 */
-	intel_pstate_set_pstate(cpu, cpu->pstate.max_pstate);
+	intel_pstate_set_pstate(cpu, cpu->pstate.min_pstate);
 }
 
 static inline void intel_pstate_calc_busy(struct cpudata *cpu)
 {
 	struct sample *sample = &cpu->sample;
-	int32_t core_pct;
-	int32_t c0_pct;
+	int64_t core_pct;
+	int32_t rem;
 
-	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 = int_tofp(sample->aperf) * int_tofp(100);
+	core_pct = div_u64_rem(core_pct, int_tofp(sample->mperf), &rem);
 
-	c0_pct = div_fp(int_tofp(sample->mperf), int_tofp(sample->tsc));
+	if ((rem << 1) >= int_tofp(sample->mperf))
+		core_pct += 1;
 
 	sample->freq = fp_toint(
 		mul_fp(int_tofp(cpu->pstate.max_pstate * 1000), core_pct));
 
-	sample->core_pct_busy = mul_fp(core_pct, c0_pct);
+	sample->core_pct_busy = (int32_t)core_pct;
 }
 
 static inline void intel_pstate_sample(struct cpudata *cpu)
 {
 	u64 aperf, mperf;
-	unsigned long long tsc;
 
 	rdmsrl(MSR_IA32_APERF, aperf);
 	rdmsrl(MSR_IA32_MPERF, mperf);
-	tsc = native_read_tsc();
 
 	aperf = aperf >> FRAC_BITS;
 	mperf = mperf >> FRAC_BITS;
-	tsc = tsc >> FRAC_BITS;
 
+	cpu->last_sample_time = cpu->sample.time;
+	cpu->sample.time = ktime_get();
 	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->prev_aperf = aperf;
 	cpu->prev_mperf = mperf;
-	cpu->prev_tsc = tsc;
 }
 
 static inline void intel_pstate_set_sample_time(struct cpudata *cpu)
@@ -603,13 +606,25 @@ static inline void intel_pstate_set_sample_time(struct cpudata *cpu)
 
 static inline int32_t intel_pstate_get_scaled_busy(struct cpudata *cpu)
 {
-	int32_t core_busy, max_pstate, current_pstate;
+	int32_t core_busy, max_pstate, current_pstate, sample_ratio;
+	u32 duration_us;
+	u32 sample_time;
 
 	core_busy = cpu->sample.core_pct_busy;
 	max_pstate = int_tofp(cpu->pstate.max_pstate);
 	current_pstate = int_tofp(cpu->pstate.current_pstate);
 	core_busy = mul_fp(core_busy, div_fp(max_pstate, current_pstate));
-	return FP_ROUNDUP(core_busy);
+
+	sample_time = (pid_params.sample_rate_ms  * USEC_PER_MSEC);
+	duration_us = (u32) ktime_us_delta(cpu->sample.time,
+					cpu->last_sample_time);
+	if (duration_us > sample_time * 3) {
+		sample_ratio = div_fp(int_tofp(sample_time),
+				int_tofp(duration_us));
+		core_busy = mul_fp(core_busy, sample_ratio);
+	}
+
+	return core_busy;
 }
 
 static inline void intel_pstate_adjust_busy_pstate(struct cpudata *cpu)
@@ -691,11 +706,6 @@ static int intel_pstate_init_cpu(unsigned int cpunum)
 	cpu = all_cpu_data[cpunum];
 
 	intel_pstate_get_cpu_pstates(cpu);
-	if (!cpu->pstate.current_pstate) {
-		all_cpu_data[cpunum] = NULL;
-		kfree(cpu);
-		return -ENODATA;
-	}
 
 	cpu->cpu = cpunum;
 
@@ -706,7 +716,6 @@ static int intel_pstate_init_cpu(unsigned int cpunum)
 	cpu->timer.expires = jiffies + HZ/100;
 	intel_pstate_busy_pid_reset(cpu);
 	intel_pstate_sample(cpu);
-	intel_pstate_set_pstate(cpu, cpu->pstate.max_pstate);
 
 	add_timer_on(&cpu->timer, cpunum);