Merge back earlier 'pm-cpufreq' material.

drivers/cpufreq/Kconfig

@@ -181,7 +181,8 @@ config CPU_FREQ_GOV_CONSERVATIVE
 
 config GENERIC_CPUFREQ_CPU0
 	tristate "Generic CPU0 cpufreq driver"
-	depends on HAVE_CLK && REGULATOR && PM_OPP && OF
+	depends on HAVE_CLK && REGULATOR && OF
+	select PM_OPP
 	help
 	  This adds a generic cpufreq driver for CPU0 frequency management.
 	  It supports both uniprocessor (UP) and symmetric multiprocessor (SMP)

drivers/cpufreq/Kconfig.arm

@@ -4,7 +4,8 @@
 
 config ARM_BIG_LITTLE_CPUFREQ
 	tristate "Generic ARM big LITTLE CPUfreq driver"
-	depends on ARM_CPU_TOPOLOGY && PM_OPP && HAVE_CLK
+	depends on ARM && ARM_CPU_TOPOLOGY && HAVE_CLK
+	select PM_OPP
 	help
 	  This enables the Generic CPUfreq driver for ARM big.LITTLE platforms.
 
@@ -54,7 +55,8 @@ config ARM_EXYNOS5250_CPUFREQ
 config ARM_EXYNOS5440_CPUFREQ
 	bool "SAMSUNG EXYNOS5440"
 	depends on SOC_EXYNOS5440
-	depends on HAVE_CLK && PM_OPP && OF
+	depends on HAVE_CLK && OF
+	select PM_OPP
 	default y
 	help
 	  This adds the CPUFreq driver for Samsung EXYNOS5440

drivers/cpufreq/cpufreq-cpu0.c

@@ -44,7 +44,7 @@ static int cpu0_set_target(struct cpufreq_policy *policy, unsigned int index)
 	int ret;
 
 	freq_Hz = clk_round_rate(cpu_clk, freq_table[index].frequency * 1000);
-	if (freq_Hz < 0)
+	if (freq_Hz <= 0)
 		freq_Hz = freq_table[index].frequency * 1000;
 
 	freq_exact = freq_Hz;

drivers/cpufreq/intel_pstate.c

@@ -35,6 +35,7 @@
 #define SAMPLE_COUNT		3
 
 #define BYT_RATIOS	0x66a
+#define BYT_VIDS        0x66b
 
 #define FRAC_BITS 8
 #define int_tofp(X) ((int64_t)(X) << FRAC_BITS)
@@ -64,6 +65,12 @@ struct pstate_data {
 	int	turbo_pstate;
 };
 
+struct vid_data {
+	int32_t min;
+	int32_t max;
+	int32_t ratio;
+};
+
 struct _pid {
 	int setpoint;
 	int32_t integral;
@@ -82,10 +89,9 @@ struct cpudata {
 	struct timer_list timer;
 
 	struct pstate_data pstate;
+	struct vid_data vid;
 	struct _pid pid;
 
-	int min_pstate_count;
-
 	u64	prev_aperf;
 	u64	prev_mperf;
 	int	sample_ptr;
@@ -106,7 +112,8 @@ struct pstate_funcs {
 	int (*get_max)(void);
 	int (*get_min)(void);
 	int (*get_turbo)(void);
-	void (*set)(int pstate);
+	void (*set)(struct cpudata*, int pstate);
+	void (*get_vid)(struct cpudata *);
 };
 
 struct cpu_defaults {
@@ -358,6 +365,42 @@ static int byt_get_max_pstate(void)
 	return (value >> 16) & 0xFF;
 }
 
+static void byt_set_pstate(struct cpudata *cpudata, int pstate)
+{
+	u64 val;
+	int32_t vid_fp;
+	u32 vid;
+
+	val = pstate << 8;
+	if (limits.no_turbo)
+		val |= (u64)1 << 32;
+
+	vid_fp = cpudata->vid.min + mul_fp(
+		int_tofp(pstate - cpudata->pstate.min_pstate),
+		cpudata->vid.ratio);
+
+	vid_fp = clamp_t(int32_t, vid_fp, cpudata->vid.min, cpudata->vid.max);
+	vid = fp_toint(vid_fp);
+
+	val |= vid;
+
+	wrmsrl(MSR_IA32_PERF_CTL, val);
+}
+
+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.ratio = div_fp(
+		cpudata->vid.max - cpudata->vid.min,
+		int_tofp(cpudata->pstate.max_pstate -
+			cpudata->pstate.min_pstate));
+}
+
+
 static int core_get_min_pstate(void)
 {
 	u64 value;
@@ -384,7 +427,7 @@ static int core_get_turbo_pstate(void)
 	return ret;
 }
 
-static void core_set_pstate(int pstate)
+static void core_set_pstate(struct cpudata *cpudata, int pstate)
 {
 	u64 val;
 
@@ -425,7 +468,8 @@ static struct cpu_defaults byt_params = {
 		.get_max = byt_get_max_pstate,
 		.get_min = byt_get_min_pstate,
 		.get_turbo = byt_get_max_pstate,
-		.set = core_set_pstate,
+		.set = byt_set_pstate,
+		.get_vid = byt_get_vid,
 	},
 };
 
@@ -462,7 +506,7 @@ static void intel_pstate_set_pstate(struct cpudata *cpu, int pstate)
 
 	cpu->pstate.current_pstate = pstate;
 
-	pstate_funcs.set(pstate);
+	pstate_funcs.set(cpu, pstate);
 }
 
 static inline void intel_pstate_pstate_increase(struct cpudata *cpu, int steps)
@@ -488,6 +532,9 @@ static void intel_pstate_get_cpu_pstates(struct cpudata *cpu)
 	cpu->pstate.max_pstate = pstate_funcs.get_max();
 	cpu->pstate.turbo_pstate = pstate_funcs.get_turbo();
 
+	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
@@ -568,15 +615,6 @@ static void intel_pstate_timer_func(unsigned long __data)
 
 	intel_pstate_sample(cpu);
 	intel_pstate_adjust_busy_pstate(cpu);
-
-	if (cpu->pstate.current_pstate == cpu->pstate.min_pstate) {
-		cpu->min_pstate_count++;
-		if (!(cpu->min_pstate_count % 5)) {
-			intel_pstate_set_pstate(cpu, cpu->pstate.max_pstate);
-		}
-	} else
-		cpu->min_pstate_count = 0;
-
 	intel_pstate_set_sample_time(cpu);
 }
 
@@ -781,6 +819,7 @@ static void copy_cpu_funcs(struct pstate_funcs *funcs)
 	pstate_funcs.get_min   = funcs->get_min;
 	pstate_funcs.get_turbo = funcs->get_turbo;
 	pstate_funcs.set       = funcs->set;
+	pstate_funcs.get_vid   = funcs->get_vid;
 }
 
 #if IS_ENABLED(CONFIG_ACPI)

drivers/cpufreq/spear-cpufreq.c

@@ -138,7 +138,7 @@ static int spear_cpufreq_target(struct cpufreq_policy *policy,
 	}
 
 	newfreq = clk_round_rate(srcclk, newfreq * mult);
-	if (newfreq < 0) {
+	if (newfreq <= 0) {
 		pr_err("clk_round_rate failed for cpu src clock\n");
 		return newfreq;
 	}