5 files changed, 197 insertions, 118 deletions

diff --git a/drivers/cpufreq/acpi-cpufreq.c b/drivers/cpufreq/acpi-cpufreq.c
index 59a7b38..fb57121 100644
--- a/drivers/cpufreq/acpi-cpufreq.c
+++ b/drivers/cpufreq/acpi-cpufreq.c
@@ -245,7 +245,7 @@ static unsigned extract_freq(u32 val, struct acpi_cpufreq_data *data)
 	}
 }
 
-u32 cpu_freq_read_intel(struct acpi_pct_register *not_used)
+static u32 cpu_freq_read_intel(struct acpi_pct_register *not_used)
 {
 	u32 val, dummy;
 
@@ -253,7 +253,7 @@ u32 cpu_freq_read_intel(struct acpi_pct_register *not_used)
 	return val;
 }
 
-void cpu_freq_write_intel(struct acpi_pct_register *not_used, u32 val)
+static void cpu_freq_write_intel(struct acpi_pct_register *not_used, u32 val)
 {
 	u32 lo, hi;
 
@@ -262,7 +262,7 @@ void cpu_freq_write_intel(struct acpi_pct_register *not_used, u32 val)
 	wrmsr(MSR_IA32_PERF_CTL, lo, hi);
 }
 
-u32 cpu_freq_read_amd(struct acpi_pct_register *not_used)
+static u32 cpu_freq_read_amd(struct acpi_pct_register *not_used)
 {
 	u32 val, dummy;
 
@@ -270,12 +270,12 @@ u32 cpu_freq_read_amd(struct acpi_pct_register *not_used)
 	return val;
 }
 
-void cpu_freq_write_amd(struct acpi_pct_register *not_used, u32 val)
+static void cpu_freq_write_amd(struct acpi_pct_register *not_used, u32 val)
 {
 	wrmsr(MSR_AMD_PERF_CTL, val, 0);
 }
 
-u32 cpu_freq_read_io(struct acpi_pct_register *reg)
+static u32 cpu_freq_read_io(struct acpi_pct_register *reg)
 {
 	u32 val;
 
@@ -283,7 +283,7 @@ u32 cpu_freq_read_io(struct acpi_pct_register *reg)
 	return val;
 }
 
-void cpu_freq_write_io(struct acpi_pct_register *reg, u32 val)
+static void cpu_freq_write_io(struct acpi_pct_register *reg, u32 val)
 {
 	acpi_os_write_port(reg->address, val, reg->bit_width);
 }
@@ -514,8 +514,10 @@ static int boost_notify(struct notifier_block *nb, unsigned long action,
 	 */
 
 	switch (action) {
-	case CPU_UP_PREPARE:
-	case CPU_UP_PREPARE_FROZEN:
+	case CPU_DOWN_FAILED:
+	case CPU_DOWN_FAILED_FROZEN:
+	case CPU_ONLINE:
+	case CPU_ONLINE_FROZEN:
 		boost_set_msrs(acpi_cpufreq_driver.boost_enabled, cpumask);
 		break;
 
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 4c78258..b87596b 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -76,6 +76,7 @@ static inline bool has_target(void)
 /* internal prototypes */
 static int cpufreq_governor(struct cpufreq_policy *policy, unsigned int event);
 static unsigned int __cpufreq_get(struct cpufreq_policy *policy);
+static int cpufreq_start_governor(struct cpufreq_policy *policy);
 
 /**
  * Two notifier lists: the "policy" list is involved in the
@@ -964,10 +965,7 @@ static int cpufreq_add_policy_cpu(struct cpufreq_policy *policy, unsigned int cp
 	cpumask_set_cpu(cpu, policy->cpus);
 
 	if (has_target()) {
-		ret = cpufreq_governor(policy, CPUFREQ_GOV_START);
-		if (!ret)
-			ret = cpufreq_governor(policy, CPUFREQ_GOV_LIMITS);
-
+		ret = cpufreq_start_governor(policy);
 		if (ret)
 			pr_err("%s: Failed to start governor\n", __func__);
 	}
@@ -1308,10 +1306,7 @@ static void cpufreq_offline(unsigned int cpu)
 	/* Start governor again for active policy */
 	if (!policy_is_inactive(policy)) {
 		if (has_target()) {
-			ret = cpufreq_governor(policy, CPUFREQ_GOV_START);
-			if (!ret)
-				ret = cpufreq_governor(policy, CPUFREQ_GOV_LIMITS);
-
+			ret = cpufreq_start_governor(policy);
 			if (ret)
 				pr_err("%s: Failed to start governor\n", __func__);
 		}
@@ -1401,9 +1396,17 @@ unsigned int cpufreq_quick_get(unsigned int cpu)
 {
 	struct cpufreq_policy *policy;
 	unsigned int ret_freq = 0;
+	unsigned long flags;
 
-	if (cpufreq_driver && cpufreq_driver->setpolicy && cpufreq_driver->get)
-		return cpufreq_driver->get(cpu);
+	read_lock_irqsave(&cpufreq_driver_lock, flags);
+
+	if (cpufreq_driver && cpufreq_driver->setpolicy && cpufreq_driver->get) {
+		ret_freq = cpufreq_driver->get(cpu);
+		read_unlock_irqrestore(&cpufreq_driver_lock, flags);
+		return ret_freq;
+	}
+
+	read_unlock_irqrestore(&cpufreq_driver_lock, flags);
 
 	policy = cpufreq_cpu_get(cpu);
 	if (policy) {
@@ -1484,6 +1487,24 @@ unsigned int cpufreq_get(unsigned int cpu)
 }
 EXPORT_SYMBOL(cpufreq_get);
 
+static unsigned int cpufreq_update_current_freq(struct cpufreq_policy *policy)
+{
+	unsigned int new_freq;
+
+	new_freq = cpufreq_driver->get(policy->cpu);
+	if (!new_freq)
+		return 0;
+
+	if (!policy->cur) {
+		pr_debug("cpufreq: Driver did not initialize current freq\n");
+		policy->cur = new_freq;
+	} else if (policy->cur != new_freq && has_target()) {
+		cpufreq_out_of_sync(policy, new_freq);
+	}
+
+	return new_freq;
+}
+
 static struct subsys_interface cpufreq_interface = {
 	.name		= "cpufreq",
 	.subsys		= &cpu_subsys,
@@ -1583,9 +1604,7 @@ void cpufreq_resume(void)
 				policy);
 		} else {
 			down_write(&policy->rwsem);
-			ret = cpufreq_governor(policy, CPUFREQ_GOV_START);
-			if (!ret)
-				cpufreq_governor(policy, CPUFREQ_GOV_LIMITS);
+			ret = cpufreq_start_governor(policy);
 			up_write(&policy->rwsem);
 
 			if (ret)
@@ -1593,17 +1612,6 @@ void cpufreq_resume(void)
 				       __func__, policy);
 		}
 	}
-
-	/*
-	 * schedule call cpufreq_update_policy() for first-online CPU, as that
-	 * wouldn't be hotplugged-out on suspend. It will verify that the
-	 * current freq is in sync with what we believe it to be.
-	 */
-	policy = cpufreq_cpu_get_raw(cpumask_first(cpu_online_mask));
-	if (WARN_ON(!policy))
-		return;
-
-	schedule_work(&policy->update);
 }
 
 /**
@@ -1927,6 +1935,17 @@ static int cpufreq_governor(struct cpufreq_policy *policy, unsigned int event)
 	return ret;
 }
 
+static int cpufreq_start_governor(struct cpufreq_policy *policy)
+{
+	int ret;
+
+	if (cpufreq_driver->get && !cpufreq_driver->setpolicy)
+		cpufreq_update_current_freq(policy);
+
+	ret = cpufreq_governor(policy, CPUFREQ_GOV_START);
+	return ret ? ret : cpufreq_governor(policy, CPUFREQ_GOV_LIMITS);
+}
+
 int cpufreq_register_governor(struct cpufreq_governor *governor)
 {
 	int err;
@@ -2063,8 +2082,10 @@ static int cpufreq_set_policy(struct cpufreq_policy *policy,
 		return cpufreq_driver->setpolicy(new_policy);
 	}
 
-	if (new_policy->governor == policy->governor)
-		goto out;
+	if (new_policy->governor == policy->governor) {
+		pr_debug("cpufreq: governor limits update\n");
+		return cpufreq_governor(policy, CPUFREQ_GOV_LIMITS);
+	}
 
 	pr_debug("governor switch\n");
 
@@ -2092,10 +2113,11 @@ static int cpufreq_set_policy(struct cpufreq_policy *policy,
 	policy->governor = new_policy->governor;
 	ret = cpufreq_governor(policy, CPUFREQ_GOV_POLICY_INIT);
 	if (!ret) {
-		ret = cpufreq_governor(policy, CPUFREQ_GOV_START);
-		if (!ret)
-			goto out;
-
+		ret = cpufreq_start_governor(policy);
+		if (!ret) {
+			pr_debug("cpufreq: governor change\n");
+			return 0;
+		}
 		cpufreq_governor(policy, CPUFREQ_GOV_POLICY_EXIT);
 	}
 
@@ -2106,14 +2128,10 @@ static int cpufreq_set_policy(struct cpufreq_policy *policy,
 		if (cpufreq_governor(policy, CPUFREQ_GOV_POLICY_INIT))
 			policy->governor = NULL;
 		else
-			cpufreq_governor(policy, CPUFREQ_GOV_START);
+			cpufreq_start_governor(policy);
 	}
 
 	return ret;
-
- out:
-	pr_debug("governor: change or update limits\n");
-	return cpufreq_governor(policy, CPUFREQ_GOV_LIMITS);
 }
 
 /**
@@ -2144,19 +2162,11 @@ int cpufreq_update_policy(unsigned int cpu)
 	 * -> ask driver for current freq and notify governors about a change
 	 */
 	if (cpufreq_driver->get && !cpufreq_driver->setpolicy) {
-		new_policy.cur = cpufreq_driver->get(cpu);
+		new_policy.cur = cpufreq_update_current_freq(policy);
 		if (WARN_ON(!new_policy.cur)) {
 			ret = -EIO;
 			goto unlock;
 		}
-
-		if (!policy->cur) {
-			pr_debug("Driver did not initialize current freq\n");
-			policy->cur = new_policy.cur;
-		} else {
-			if (policy->cur != new_policy.cur && has_target())
-				cpufreq_out_of_sync(policy, new_policy.cur);
-		}
 	}
 
 	ret = cpufreq_set_policy(policy, &new_policy);
diff --git a/drivers/cpufreq/cpufreq_governor.c b/drivers/cpufreq/cpufreq_governor.c
index 1c25ef4..10a5cfe 100644
--- a/drivers/cpufreq/cpufreq_governor.c
+++ b/drivers/cpufreq/cpufreq_governor.c
@@ -329,7 +329,7 @@ static void dbs_irq_work(struct irq_work *irq_work)
 	struct policy_dbs_info *policy_dbs;
 
 	policy_dbs = container_of(irq_work, struct policy_dbs_info, irq_work);
-	schedule_work(&policy_dbs->work);
+	schedule_work_on(smp_processor_id(), &policy_dbs->work);
 }
 
 static void dbs_update_util_handler(struct update_util_data *data, u64 time,
diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c
index cb56074..4b64452 100644
--- a/drivers/cpufreq/intel_pstate.c
+++ b/drivers/cpufreq/intel_pstate.c
@@ -134,7 +134,7 @@ struct pstate_funcs {
 	int (*get_min)(void);
 	int (*get_turbo)(void);
 	int (*get_scaling)(void);
-	void (*set)(struct cpudata*, int pstate);
+	u64 (*get_val)(struct cpudata*, int pstate);
 	void (*get_vid)(struct cpudata *);
 	int32_t (*get_target_pstate)(struct cpudata *);
 };
@@ -565,7 +565,7 @@ static int atom_get_turbo_pstate(void)
 	return value & 0x7F;
 }
 
-static void atom_set_pstate(struct cpudata *cpudata, int pstate)
+static u64 atom_get_val(struct cpudata *cpudata, int pstate)
 {
 	u64 val;
 	int32_t vid_fp;
@@ -585,9 +585,7 @@ static void atom_set_pstate(struct cpudata *cpudata, int pstate)
 	if (pstate > cpudata->pstate.max_pstate)
 		vid = cpudata->vid.turbo;
 
-	val |= vid;
-
-	wrmsrl_on_cpu(cpudata->cpu, MSR_IA32_PERF_CTL, val);
+	return val | vid;
 }
 
 static int silvermont_get_scaling(void)
@@ -711,7 +709,7 @@ static inline int core_get_scaling(void)
 	return 100000;
 }
 
-static void core_set_pstate(struct cpudata *cpudata, int pstate)
+static u64 core_get_val(struct cpudata *cpudata, int pstate)
 {
 	u64 val;
 
@@ -719,7 +717,7 @@ static void core_set_pstate(struct cpudata *cpudata, int pstate)
 	if (limits->no_turbo && !limits->turbo_disabled)
 		val |= (u64)1 << 32;
 
-	wrmsrl(MSR_IA32_PERF_CTL, val);
+	return val;
 }
 
 static int knl_get_turbo_pstate(void)
@@ -750,7 +748,7 @@ static struct cpu_defaults core_params = {
 		.get_min = core_get_min_pstate,
 		.get_turbo = core_get_turbo_pstate,
 		.get_scaling = core_get_scaling,
-		.set = core_set_pstate,
+		.get_val = core_get_val,
 		.get_target_pstate = get_target_pstate_use_performance,
 	},
 };
@@ -769,7 +767,7 @@ static struct cpu_defaults silvermont_params = {
 		.get_max_physical = atom_get_max_pstate,
 		.get_min = atom_get_min_pstate,
 		.get_turbo = atom_get_turbo_pstate,
-		.set = atom_set_pstate,
+		.get_val = atom_get_val,
 		.get_scaling = silvermont_get_scaling,
 		.get_vid = atom_get_vid,
 		.get_target_pstate = get_target_pstate_use_cpu_load,
@@ -790,7 +788,7 @@ static struct cpu_defaults airmont_params = {
 		.get_max_physical = atom_get_max_pstate,
 		.get_min = atom_get_min_pstate,
 		.get_turbo = atom_get_turbo_pstate,
-		.set = atom_set_pstate,
+		.get_val = atom_get_val,
 		.get_scaling = airmont_get_scaling,
 		.get_vid = atom_get_vid,
 		.get_target_pstate = get_target_pstate_use_cpu_load,
@@ -812,7 +810,7 @@ static struct cpu_defaults knl_params = {
 		.get_min = core_get_min_pstate,
 		.get_turbo = knl_get_turbo_pstate,
 		.get_scaling = core_get_scaling,
-		.set = core_set_pstate,
+		.get_val = core_get_val,
 		.get_target_pstate = get_target_pstate_use_performance,
 	},
 };
@@ -839,25 +837,24 @@ static void intel_pstate_get_min_max(struct cpudata *cpu, int *min, int *max)
 	*min = clamp_t(int, min_perf, cpu->pstate.min_pstate, max_perf);
 }
 
-static void intel_pstate_set_pstate(struct cpudata *cpu, int pstate, bool force)
+static inline void intel_pstate_record_pstate(struct cpudata *cpu, int pstate)
 {
-	int max_perf, min_perf;
-
-	if (force) {
-		update_turbo_state();
-
-		intel_pstate_get_min_max(cpu, &min_perf, &max_perf);
-
-		pstate = clamp_t(int, pstate, min_perf, max_perf);
-
-		if (pstate == cpu->pstate.current_pstate)
-			return;
-	}
 	trace_cpu_frequency(pstate * cpu->pstate.scaling, cpu->cpu);
-
 	cpu->pstate.current_pstate = pstate;
+}
 
-	pstate_funcs.set(cpu, pstate);
+static void intel_pstate_set_min_pstate(struct cpudata *cpu)
+{
+	int pstate = cpu->pstate.min_pstate;
+
+	intel_pstate_record_pstate(cpu, pstate);
+	/*
+	 * Generally, there is no guarantee that this code will always run on
+	 * the CPU being updated, so force the register update to run on the
+	 * right CPU.
+	 */
+	wrmsrl_on_cpu(cpu->cpu, MSR_IA32_PERF_CTL,
+		      pstate_funcs.get_val(cpu, pstate));
 }
 
 static void intel_pstate_get_cpu_pstates(struct cpudata *cpu)
@@ -870,7 +867,8 @@ static void intel_pstate_get_cpu_pstates(struct cpudata *cpu)
 
 	if (pstate_funcs.get_vid)
 		pstate_funcs.get_vid(cpu);
-	intel_pstate_set_pstate(cpu, cpu->pstate.min_pstate, false);
+
+	intel_pstate_set_min_pstate(cpu);
 }
 
 static inline void intel_pstate_calc_busy(struct cpudata *cpu)
@@ -997,6 +995,21 @@ static inline int32_t get_target_pstate_use_performance(struct cpudata *cpu)
 	return cpu->pstate.current_pstate - pid_calc(&cpu->pid, core_busy);
 }
 
+static inline void intel_pstate_update_pstate(struct cpudata *cpu, int pstate)
+{
+	int max_perf, min_perf;
+
+	update_turbo_state();
+
+	intel_pstate_get_min_max(cpu, &min_perf, &max_perf);
+	pstate = clamp_t(int, pstate, min_perf, max_perf);
+	if (pstate == cpu->pstate.current_pstate)
+		return;
+
+	intel_pstate_record_pstate(cpu, pstate);
+	wrmsrl(MSR_IA32_PERF_CTL, pstate_funcs.get_val(cpu, pstate));
+}
+
 static inline void intel_pstate_adjust_busy_pstate(struct cpudata *cpu)
 {
 	int from, target_pstate;
@@ -1006,7 +1019,7 @@ static inline void intel_pstate_adjust_busy_pstate(struct cpudata *cpu)
 
 	target_pstate = pstate_funcs.get_target_pstate(cpu);
 
-	intel_pstate_set_pstate(cpu, target_pstate, true);
+	intel_pstate_update_pstate(cpu, target_pstate);
 
 	sample = &cpu->sample;
 	trace_pstate_sample(fp_toint(sample->core_pct_busy),
@@ -1180,7 +1193,7 @@ static void intel_pstate_stop_cpu(struct cpufreq_policy *policy)
 	if (hwp_active)
 		return;
 
-	intel_pstate_set_pstate(cpu, cpu->pstate.min_pstate, false);
+	intel_pstate_set_min_pstate(cpu);
 }
 
 static int intel_pstate_cpu_init(struct cpufreq_policy *policy)
@@ -1255,7 +1268,7 @@ 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.get_scaling = funcs->get_scaling;
-	pstate_funcs.set       = funcs->set;
+	pstate_funcs.get_val   = funcs->get_val;
 	pstate_funcs.get_vid   = funcs->get_vid;
 	pstate_funcs.get_target_pstate = funcs->get_target_pstate;
 
diff --git a/drivers/cpufreq/powernv-cpufreq.c b/drivers/cpufreq/powernv-cpufreq.c
index 50bf120..39ac78c 100644
--- a/drivers/cpufreq/powernv-cpufreq.c
+++ b/drivers/cpufreq/powernv-cpufreq.c
@@ -44,7 +44,6 @@
 
 static struct cpufreq_frequency_table powernv_freqs[POWERNV_MAX_PSTATES+1];
 static bool rebooting, throttled, occ_reset;
-static unsigned int *core_to_chip_map;
 
 static const char * const throttle_reason[] = {
 	"No throttling",
@@ -55,6 +54,16 @@ static const char * const throttle_reason[] = {
 	"OCC Reset"
 };
 
+enum throttle_reason_type {
+	NO_THROTTLE = 0,
+	POWERCAP,
+	CPU_OVERTEMP,
+	POWER_SUPPLY_FAILURE,
+	OVERCURRENT,
+	OCC_RESET_THROTTLE,
+	OCC_MAX_REASON
+};
+
 static struct chip {
 	unsigned int id;
 	bool throttled;
@@ -62,9 +71,13 @@ static struct chip {
 	u8 throttle_reason;
 	cpumask_t mask;
 	struct work_struct throttle;
+	int throttle_turbo;
+	int throttle_sub_turbo;
+	int reason[OCC_MAX_REASON];
 } *chips;
 
 static int nr_chips;
+static DEFINE_PER_CPU(struct chip *, chip_info);
 
 /*
  * Note: The set of pstates consists of contiguous integers, the
@@ -196,6 +209,42 @@ static struct freq_attr *powernv_cpu_freq_attr[] = {
 	NULL,
 };
 
+#define throttle_attr(name, member)					\
+static ssize_t name##_show(struct cpufreq_policy *policy, char *buf)	\
+{									\
+	struct chip *chip = per_cpu(chip_info, policy->cpu);		\
+									\
+	return sprintf(buf, "%u\n", chip->member);			\
+}									\
+									\
+static struct freq_attr throttle_attr_##name = __ATTR_RO(name)		\
+
+throttle_attr(unthrottle, reason[NO_THROTTLE]);
+throttle_attr(powercap, reason[POWERCAP]);
+throttle_attr(overtemp, reason[CPU_OVERTEMP]);
+throttle_attr(supply_fault, reason[POWER_SUPPLY_FAILURE]);
+throttle_attr(overcurrent, reason[OVERCURRENT]);
+throttle_attr(occ_reset, reason[OCC_RESET_THROTTLE]);
+throttle_attr(turbo_stat, throttle_turbo);
+throttle_attr(sub_turbo_stat, throttle_sub_turbo);
+
+static struct attribute *throttle_attrs[] = {
+	&throttle_attr_unthrottle.attr,
+	&throttle_attr_powercap.attr,
+	&throttle_attr_overtemp.attr,
+	&throttle_attr_supply_fault.attr,
+	&throttle_attr_overcurrent.attr,
+	&throttle_attr_occ_reset.attr,
+	&throttle_attr_turbo_stat.attr,
+	&throttle_attr_sub_turbo_stat.attr,
+	NULL,
+};
+
+static const struct attribute_group throttle_attr_grp = {
+	.name	= "throttle_stats",
+	.attrs	= throttle_attrs,
+};
+
 /* Helper routines */
 
 /* Access helpers to power mgt SPR */
@@ -324,34 +373,35 @@ static inline unsigned int get_nominal_index(void)
 
 static void powernv_cpufreq_throttle_check(void *data)
 {
+	struct chip *chip;
 	unsigned int cpu = smp_processor_id();
-	unsigned int chip_id = core_to_chip_map[cpu_core_index_of_thread(cpu)];
 	unsigned long pmsr;
-	int pmsr_pmax, i;
+	int pmsr_pmax;
 
 	pmsr = get_pmspr(SPRN_PMSR);
-
-	for (i = 0; i < nr_chips; i++)
-		if (chips[i].id == chip_id)
-			break;
+	chip = this_cpu_read(chip_info);
 
 	/* Check for Pmax Capping */
 	pmsr_pmax = (s8)PMSR_MAX(pmsr);
 	if (pmsr_pmax != powernv_pstate_info.max) {
-		if (chips[i].throttled)
+		if (chip->throttled)
 			goto next;
-		chips[i].throttled = true;
-		if (pmsr_pmax < powernv_pstate_info.nominal)
+		chip->throttled = true;
+		if (pmsr_pmax < powernv_pstate_info.nominal) {
 			pr_warn_once("CPU %d on Chip %u has Pmax reduced below nominal frequency (%d < %d)\n",
-				     cpu, chips[i].id, pmsr_pmax,
+				     cpu, chip->id, pmsr_pmax,
 				     powernv_pstate_info.nominal);
-		trace_powernv_throttle(chips[i].id,
-				      throttle_reason[chips[i].throttle_reason],
+			chip->throttle_sub_turbo++;
+		} else {
+			chip->throttle_turbo++;
+		}
+		trace_powernv_throttle(chip->id,
+				      throttle_reason[chip->throttle_reason],
 				      pmsr_pmax);
-	} else if (chips[i].throttled) {
-		chips[i].throttled = false;
-		trace_powernv_throttle(chips[i].id,
-				      throttle_reason[chips[i].throttle_reason],
+	} else if (chip->throttled) {
+		chip->throttled = false;
+		trace_powernv_throttle(chip->id,
+				      throttle_reason[chip->throttle_reason],
 				      pmsr_pmax);
 	}
 
@@ -411,6 +461,21 @@ static int powernv_cpufreq_cpu_init(struct cpufreq_policy *policy)
 	for (i = 0; i < threads_per_core; i++)
 		cpumask_set_cpu(base + i, policy->cpus);
 
+	if (!policy->driver_data) {
+		int ret;
+
+		ret = sysfs_create_group(&policy->kobj, &throttle_attr_grp);
+		if (ret) {
+			pr_info("Failed to create throttle stats directory for cpu %d\n",
+				policy->cpu);
+			return ret;
+		}
+		/*
+		 * policy->driver_data is used as a flag for one-time
+		 * creation of throttle sysfs files.
+		 */
+		policy->driver_data = policy;
+	}
 	return cpufreq_table_validate_and_show(policy, powernv_freqs);
 }
 
@@ -517,8 +582,10 @@ static int powernv_cpufreq_occ_msg(struct notifier_block *nb,
 				break;
 
 		if (omsg.throttle_status >= 0 &&
-		    omsg.throttle_status <= OCC_MAX_THROTTLE_STATUS)
+		    omsg.throttle_status <= OCC_MAX_THROTTLE_STATUS) {
 			chips[i].throttle_reason = omsg.throttle_status;
+			chips[i].reason[omsg.throttle_status]++;
+		}
 
 		if (!omsg.throttle_status)
 			chips[i].restore = true;
@@ -558,47 +625,34 @@ static int init_chip_info(void)
 	unsigned int chip[256];
 	unsigned int cpu, i;
 	unsigned int prev_chip_id = UINT_MAX;
-	cpumask_t cpu_mask;
-	int ret = -ENOMEM;
-
-	core_to_chip_map = kcalloc(cpu_nr_cores(), sizeof(unsigned int),
-				   GFP_KERNEL);
-	if (!core_to_chip_map)
-		goto out;
 
-	cpumask_copy(&cpu_mask, cpu_possible_mask);
-	for_each_cpu(cpu, &cpu_mask) {
+	for_each_possible_cpu(cpu) {
 		unsigned int id = cpu_to_chip_id(cpu);
 
 		if (prev_chip_id != id) {
 			prev_chip_id = id;
 			chip[nr_chips++] = id;
 		}
-		core_to_chip_map[cpu_core_index_of_thread(cpu)] = id;
-		cpumask_andnot(&cpu_mask, &cpu_mask, cpu_sibling_mask(cpu));
 	}
 
 	chips = kcalloc(nr_chips, sizeof(struct chip), GFP_KERNEL);
 	if (!chips)
-		goto free_chip_map;
+		return -ENOMEM;
 
 	for (i = 0; i < nr_chips; i++) {
 		chips[i].id = chip[i];
 		cpumask_copy(&chips[i].mask, cpumask_of_node(chip[i]));
 		INIT_WORK(&chips[i].throttle, powernv_cpufreq_work_fn);
+		for_each_cpu(cpu, &chips[i].mask)
+			per_cpu(chip_info, cpu) =  &chips[i];
 	}
 
 	return 0;
-free_chip_map:
-	kfree(core_to_chip_map);
-out:
-	return ret;
 }
 
 static inline void clean_chip_info(void)
 {
 	kfree(chips);
-	kfree(core_to_chip_map);
 }
 
 static inline void unregister_all_notifiers(void)