Merge tag 'pm+acpi-3.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull ACPI and power management updates from Rafael Wysocki:
 "We have a few new features this time, including a new SFI-based
  cpufreq driver, a new devfreq driver for Tegra Activity Monitor, a new
  devfreq class for providing its governors with raw utilization data
  and a new ACPI driver for AMD SoCs.

  Still, the majority of changes here are reworks of existing code to
  make it more straightforward or to prepare it for implementing new
  features on top of it.  The primary example is the rework of ACPI
  resources handling from Jiang Liu, Thomas Gleixner and Lv Zheng with
  support for IOAPIC hotplug implemented on top of it, but there is
  quite a number of changes of this kind in the cpufreq core, ACPICA,
  ACPI EC driver, ACPI processor driver and the generic power domains
  core code too.

  The most active developer is Viresh Kumar with his cpufreq changes.

  Specifics:

   - Rework of the core ACPI resources parsing code to fix issues in it
     and make using resource offsets more convenient and consolidation
     of some resource-handing code in a couple of places that have grown
     analagous data structures and code to cover the the same gap in the
     core (Jiang Liu, Thomas Gleixner, Lv Zheng).

   - ACPI-based IOAPIC hotplug support on top of the resources handling
     rework (Jiang Liu, Yinghai Lu).

   - ACPICA update to upstream release 20150204 including an interrupt
     handling rework that allows drivers to install raw handlers for
     ACPI GPEs which then become entirely responsible for the given GPE
     and the ACPICA core code won't touch it (Lv Zheng, David E Box,
     Octavian Purdila).

   - ACPI EC driver rework to fix several concurrency issues and other
     problems related to events handling on top of the ACPICA's new
     support for raw GPE handlers (Lv Zheng).

   - New ACPI driver for AMD SoCs analogous to the LPSS (Low-Power
     Subsystem) driver for Intel chips (Ken Xue).

   - Two minor fixes of the ACPI LPSS driver (Heikki Krogerus, Jarkko
     Nikula).

   - Two new blacklist entries for machines (Samsung 730U3E/740U3E and
     510R) where the native backlight interface doesn't work correctly
     while the ACPI one does (Hans de Goede).

   - Rework of the ACPI processor driver's handling of idle states to
     make the code more straightforward and less bloated overall (Rafael
     J Wysocki).

   - Assorted minor fixes related to ACPI and SFI (Andreas Ruprecht,
     Andy Shevchenko, Hanjun Guo, Jan Beulich, Rafael J Wysocki, Yaowei
     Bai).

   - PCI core power management modification to avoid resuming (some)
     runtime-suspended devices during system suspend if they are in the
     right states already (Rafael J Wysocki).

   - New SFI-based cpufreq driver for Intel platforms using SFI
     (Srinidhi Kasagar).

   - cpufreq core fixes, cleanups and simplifications (Viresh Kumar,
     Doug Anderson, Wolfram Sang).

   - SkyLake CPU support and other updates for the intel_pstate driver
     (Kristen Carlson Accardi, Srinivas Pandruvada).

   - cpufreq-dt driver cleanup (Markus Elfring).

   - Init fix for the ARM big.LITTLE cpuidle driver (Sudeep Holla).

   - Generic power domains core code fixes and cleanups (Ulf Hansson).

   - Operating Performance Points (OPP) core code cleanups and kernel
     documentation update (Nishanth Menon).

   - New dabugfs interface to make the list of PM QoS constraints
     available to user space (Nishanth Menon).

   - New devfreq driver for Tegra Activity Monitor (Tomeu Vizoso).

   - New devfreq class (devfreq_event) to provide raw utilization data
     to devfreq governors (Chanwoo Choi).

   - Assorted minor fixes and cleanups related to power management
     (Andreas Ruprecht, Krzysztof Kozlowski, Rickard Strandqvist, Pavel
     Machek, Todd E Brandt, Wonhong Kwon).

   - turbostat updates (Len Brown) and cpupower Makefile improvement
     (Sriram Raghunathan)"

* tag 'pm+acpi-3.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (151 commits)
  tools/power turbostat: relax dependency on APERF_MSR
  tools/power turbostat: relax dependency on invariant TSC
  Merge branch 'pci/host-generic' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci into acpi-resources
  tools/power turbostat: decode MSR_*_PERF_LIMIT_REASONS
  tools/power turbostat: relax dependency on root permission
  ACPI / video: Add disable_native_backlight quirk for Samsung 510R
  ACPI / PM: Remove unneeded nested #ifdef
  USB / PM: Remove unneeded #ifdef and associated dead code
  intel_pstate: provide option to only use intel_pstate with HWP
  ACPI / EC: Add GPE reference counting debugging messages
  ACPI / EC: Add query flushing support
  ACPI / EC: Refine command storm prevention support
  ACPI / EC: Add command flushing support.
  ACPI / EC: Introduce STARTED/STOPPED flags to replace BLOCKED flag
  ACPI: add AMD ACPI2Platform device support for x86 system
  ACPI / table: remove duplicate NULL check for the handler of acpi_table_parse()
  ACPI / EC: Update revision due to raw handler mode.
  ACPI / EC: Reduce ec_poll() by referencing the last register access timestamp.
  ACPI / EC: Fix several GPE handling issues by deploying ACPI_GPE_DISPATCH_RAW_HANDLER mode.
  ACPICA: Events: Enable APIs to allow interrupt/polling adaptive request based GPE handling model
  ...

8 files changed, 367 insertions, 232 deletions

diff --git a/drivers/cpufreq/Kconfig.x86 b/drivers/cpufreq/Kconfig.x86
index 89ae88f91895..c59bdcb83217 100644
--- a/drivers/cpufreq/Kconfig.x86
+++ b/drivers/cpufreq/Kconfig.x86
@@ -57,6 +57,16 @@ config X86_ACPI_CPUFREQ_CPB
 	  By enabling this option the acpi_cpufreq driver provides the old
 	  entry in addition to the new boost ones, for compatibility reasons.
 
+config X86_SFI_CPUFREQ
+	tristate "SFI Performance-States driver"
+	depends on X86_INTEL_MID && SFI
+	help
+	  This adds a CPUFreq driver for some Silvermont based Intel Atom
+	  architectures like Z34xx and Z35xx which enumerate processor
+	  performance states through SFI.
+
+	  If in doubt, say N.
+
 config ELAN_CPUFREQ
 	tristate "AMD Elan SC400 and SC410"
 	depends on MELAN
diff --git a/drivers/cpufreq/Makefile b/drivers/cpufreq/Makefile
index b3ca7b0b2c33..8b4220ac888b 100644
--- a/drivers/cpufreq/Makefile
+++ b/drivers/cpufreq/Makefile
@@ -41,6 +41,7 @@ obj-$(CONFIG_X86_P4_CLOCKMOD)		+= p4-clockmod.o
 obj-$(CONFIG_X86_CPUFREQ_NFORCE2)	+= cpufreq-nforce2.o
 obj-$(CONFIG_X86_INTEL_PSTATE)		+= intel_pstate.o
 obj-$(CONFIG_X86_AMD_FREQ_SENSITIVITY)	+= amd_freq_sensitivity.o
+obj-$(CONFIG_X86_SFI_CPUFREQ)		+= sfi-cpufreq.o
 
 ##################################################################################
 # ARM SoC drivers
diff --git a/drivers/cpufreq/cpufreq-dt.c b/drivers/cpufreq/cpufreq-dt.c
index fde97d6e31d6..bab67db54b7e 100644
--- a/drivers/cpufreq/cpufreq-dt.c
+++ b/drivers/cpufreq/cpufreq-dt.c
@@ -320,8 +320,7 @@ static int cpufreq_exit(struct cpufreq_policy *policy)
 {
 	struct private_data *priv = policy->driver_data;
 
-	if (priv->cdev)
-		cpufreq_cooling_unregister(priv->cdev);
+	cpufreq_cooling_unregister(priv->cdev);
 	dev_pm_opp_free_cpufreq_table(priv->cpu_dev, &policy->freq_table);
 	of_free_opp_table(priv->cpu_dev);
 	clk_put(policy->clk);
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 46bed4f81cde..28e59a48b35f 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -27,9 +27,21 @@
 #include <linux/mutex.h>
 #include <linux/slab.h>
 #include <linux/suspend.h>
+#include <linux/syscore_ops.h>
 #include <linux/tick.h>
 #include <trace/events/power.h>
 
+/* Macros to iterate over lists */
+/* Iterate over online CPUs policies */
+static LIST_HEAD(cpufreq_policy_list);
+#define for_each_policy(__policy)				\
+	list_for_each_entry(__policy, &cpufreq_policy_list, policy_list)
+
+/* Iterate over governors */
+static LIST_HEAD(cpufreq_governor_list);
+#define for_each_governor(__governor)				\
+	list_for_each_entry(__governor, &cpufreq_governor_list, governor_list)
+
 /**
  * The "cpufreq driver" - the arch- or hardware-dependent low
  * level driver of CPUFreq support, and its spinlock. This lock
@@ -40,7 +52,6 @@ static DEFINE_PER_CPU(struct cpufreq_policy *, cpufreq_cpu_data);
 static DEFINE_PER_CPU(struct cpufreq_policy *, cpufreq_cpu_data_fallback);
 static DEFINE_RWLOCK(cpufreq_driver_lock);
 DEFINE_MUTEX(cpufreq_governor_lock);
-static LIST_HEAD(cpufreq_policy_list);
 
 /* This one keeps track of the previously set governor of a removed CPU */
 static DEFINE_PER_CPU(char[CPUFREQ_NAME_LEN], cpufreq_cpu_governor);
@@ -62,7 +73,7 @@ static DECLARE_RWSEM(cpufreq_rwsem);
 /* internal prototypes */
 static int __cpufreq_governor(struct cpufreq_policy *policy,
 		unsigned int event);
-static unsigned int __cpufreq_get(unsigned int cpu);
+static unsigned int __cpufreq_get(struct cpufreq_policy *policy);
 static void handle_update(struct work_struct *work);
 
 /**
@@ -93,7 +104,6 @@ void disable_cpufreq(void)
 {
 	off = 1;
 }
-static LIST_HEAD(cpufreq_governor_list);
 static DEFINE_MUTEX(cpufreq_governor_mutex);
 
 bool have_governor_per_policy(void)
@@ -202,7 +212,7 @@ struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu)
 	struct cpufreq_policy *policy = NULL;
 	unsigned long flags;
 
-	if (cpufreq_disabled() || (cpu >= nr_cpu_ids))
+	if (cpu >= nr_cpu_ids)
 		return NULL;
 
 	if (!down_read_trylock(&cpufreq_rwsem))
@@ -229,9 +239,6 @@ EXPORT_SYMBOL_GPL(cpufreq_cpu_get);
 
 void cpufreq_cpu_put(struct cpufreq_policy *policy)
 {
-	if (cpufreq_disabled())
-		return;
-
 	kobject_put(&policy->kobj);
 	up_read(&cpufreq_rwsem);
 }
@@ -249,12 +256,12 @@ EXPORT_SYMBOL_GPL(cpufreq_cpu_put);
  * systems as each CPU might be scaled differently. So, use the arch
  * per-CPU loops_per_jiffy value wherever possible.
  */
-#ifndef CONFIG_SMP
-static unsigned long l_p_j_ref;
-static unsigned int l_p_j_ref_freq;
-
 static void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci)
 {
+#ifndef CONFIG_SMP
+	static unsigned long l_p_j_ref;
+	static unsigned int l_p_j_ref_freq;
+
 	if (ci->flags & CPUFREQ_CONST_LOOPS)
 		return;
 
@@ -270,13 +277,8 @@ static void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci)
 		pr_debug("scaling loops_per_jiffy to %lu for frequency %u kHz\n",
 			 loops_per_jiffy, ci->new);
 	}
-}
-#else
-static inline void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci)
-{
-	return;
-}
 #endif
+}
 
 static void __cpufreq_notify_transition(struct cpufreq_policy *policy,
 		struct cpufreq_freqs *freqs, unsigned int state)
@@ -432,11 +434,11 @@ static ssize_t store_boost(struct kobject *kobj, struct attribute *attr,
 }
 define_one_global_rw(boost);
 
-static struct cpufreq_governor *__find_governor(const char *str_governor)
+static struct cpufreq_governor *find_governor(const char *str_governor)
 {
 	struct cpufreq_governor *t;
 
-	list_for_each_entry(t, &cpufreq_governor_list, governor_list)
+	for_each_governor(t)
 		if (!strncasecmp(str_governor, t->name, CPUFREQ_NAME_LEN))
 			return t;
 
@@ -463,12 +465,12 @@ static int cpufreq_parse_governor(char *str_governor, unsigned int *policy,
 			*policy = CPUFREQ_POLICY_POWERSAVE;
 			err = 0;
 		}
-	} else if (has_target()) {
+	} else {
 		struct cpufreq_governor *t;
 
 		mutex_lock(&cpufreq_governor_mutex);
 
-		t = __find_governor(str_governor);
+		t = find_governor(str_governor);
 
 		if (t == NULL) {
 			int ret;
@@ -478,7 +480,7 @@ static int cpufreq_parse_governor(char *str_governor, unsigned int *policy,
 			mutex_lock(&cpufreq_governor_mutex);
 
 			if (ret == 0)
-				t = __find_governor(str_governor);
+				t = find_governor(str_governor);
 		}
 
 		if (t != NULL) {
@@ -513,8 +515,7 @@ show_one(cpuinfo_transition_latency, cpuinfo.transition_latency);
 show_one(scaling_min_freq, min);
 show_one(scaling_max_freq, max);
 
-static ssize_t show_scaling_cur_freq(
-	struct cpufreq_policy *policy, char *buf)
+static ssize_t show_scaling_cur_freq(struct cpufreq_policy *policy, char *buf)
 {
 	ssize_t ret;
 
@@ -563,7 +564,7 @@ store_one(scaling_max_freq, max);
 static ssize_t show_cpuinfo_cur_freq(struct cpufreq_policy *policy,
 					char *buf)
 {
-	unsigned int cur_freq = __cpufreq_get(policy->cpu);
+	unsigned int cur_freq = __cpufreq_get(policy);
 	if (!cur_freq)
 		return sprintf(buf, "<unknown>");
 	return sprintf(buf, "%u\n", cur_freq);
@@ -639,7 +640,7 @@ static ssize_t show_scaling_available_governors(struct cpufreq_policy *policy,
 		goto out;
 	}
 
-	list_for_each_entry(t, &cpufreq_governor_list, governor_list) {
+	for_each_governor(t) {
 		if (i >= (ssize_t) ((PAGE_SIZE / sizeof(char))
 		    - (CPUFREQ_NAME_LEN + 2)))
 			goto out;
@@ -902,7 +903,7 @@ static int cpufreq_add_dev_interface(struct cpufreq_policy *policy,
 
 	/* set up files for this cpu device */
 	drv_attr = cpufreq_driver->attr;
-	while ((drv_attr) && (*drv_attr)) {
+	while (drv_attr && *drv_attr) {
 		ret = sysfs_create_file(&policy->kobj, &((*drv_attr)->attr));
 		if (ret)
 			return ret;
@@ -936,7 +937,7 @@ static void cpufreq_init_policy(struct cpufreq_policy *policy)
 	memcpy(&new_policy, policy, sizeof(*policy));
 
 	/* Update governor of new_policy to the governor used before hotplug */
-	gov = __find_governor(per_cpu(cpufreq_cpu_governor, policy->cpu));
+	gov = find_governor(per_cpu(cpufreq_cpu_governor, policy->cpu));
 	if (gov)
 		pr_debug("Restoring governor %s for cpu %d\n",
 				policy->governor->name, policy->cpu);
@@ -958,7 +959,6 @@ static void cpufreq_init_policy(struct cpufreq_policy *policy)
 	}
 }
 
-#ifdef CONFIG_HOTPLUG_CPU
 static int cpufreq_add_policy_cpu(struct cpufreq_policy *policy,
 				  unsigned int cpu, struct device *dev)
 {
@@ -996,7 +996,6 @@ static int cpufreq_add_policy_cpu(struct cpufreq_policy *policy,
 
 	return sysfs_create_link(&dev->kobj, &policy->kobj, "cpufreq");
 }
-#endif
 
 static struct cpufreq_policy *cpufreq_policy_restore(unsigned int cpu)
 {
@@ -1033,6 +1032,8 @@ static struct cpufreq_policy *cpufreq_policy_alloc(void)
 	init_rwsem(&policy->rwsem);
 	spin_lock_init(&policy->transition_lock);
 	init_waitqueue_head(&policy->transition_wait);
+	init_completion(&policy->kobj_unregister);
+	INIT_WORK(&policy->update, handle_update);
 
 	return policy;
 
@@ -1091,15 +1092,9 @@ static int update_policy_cpu(struct cpufreq_policy *policy, unsigned int cpu,
 	}
 
 	down_write(&policy->rwsem);
-
-	policy->last_cpu = policy->cpu;
 	policy->cpu = cpu;
-
 	up_write(&policy->rwsem);
 
-	blocking_notifier_call_chain(&cpufreq_policy_notifier_list,
-			CPUFREQ_UPDATE_POLICY_CPU, policy);
-
 	return 0;
 }
 
@@ -1110,41 +1105,32 @@ static int __cpufreq_add_dev(struct device *dev, struct subsys_interface *sif)
 	struct cpufreq_policy *policy;
 	unsigned long flags;
 	bool recover_policy = cpufreq_suspended;
-#ifdef CONFIG_HOTPLUG_CPU
-	struct cpufreq_policy *tpolicy;
-#endif
 
 	if (cpu_is_offline(cpu))
 		return 0;
 
 	pr_debug("adding CPU %u\n", cpu);
 
-#ifdef CONFIG_SMP
 	/* check whether a different CPU already registered this
 	 * CPU because it is in the same boat. */
-	policy = cpufreq_cpu_get(cpu);
-	if (unlikely(policy)) {
-		cpufreq_cpu_put(policy);
+	policy = cpufreq_cpu_get_raw(cpu);
+	if (unlikely(policy))
 		return 0;
-	}
-#endif
 
 	if (!down_read_trylock(&cpufreq_rwsem))
 		return 0;
 
-#ifdef CONFIG_HOTPLUG_CPU
 	/* Check if this cpu was hot-unplugged earlier and has siblings */
 	read_lock_irqsave(&cpufreq_driver_lock, flags);
-	list_for_each_entry(tpolicy, &cpufreq_policy_list, policy_list) {
-		if (cpumask_test_cpu(cpu, tpolicy->related_cpus)) {
+	for_each_policy(policy) {
+		if (cpumask_test_cpu(cpu, policy->related_cpus)) {
 			read_unlock_irqrestore(&cpufreq_driver_lock, flags);
-			ret = cpufreq_add_policy_cpu(tpolicy, cpu, dev);
+			ret = cpufreq_add_policy_cpu(policy, cpu, dev);
 			up_read(&cpufreq_rwsem);
 			return ret;
 		}
 	}
 	read_unlock_irqrestore(&cpufreq_driver_lock, flags);
-#endif
 
 	/*
 	 * Restore the saved policy when doing light-weight init and fall back
@@ -1171,9 +1157,6 @@ static int __cpufreq_add_dev(struct device *dev, struct subsys_interface *sif)
 
 	cpumask_copy(policy->cpus, cpumask_of(cpu));
 
-	init_completion(&policy->kobj_unregister);
-	INIT_WORK(&policy->update, handle_update);
-
 	/* call driver. From then on the cpufreq must be able
 	 * to accept all calls to ->verify and ->setpolicy for this CPU
 	 */
@@ -1371,11 +1354,10 @@ static int __cpufreq_remove_dev_prepare(struct device *dev,
 			pr_err("%s: Failed to stop governor\n", __func__);
 			return ret;
 		}
-	}
 
-	if (!cpufreq_driver->setpolicy)
 		strncpy(per_cpu(cpufreq_cpu_governor, cpu),
 			policy->governor->name, CPUFREQ_NAME_LEN);
+	}
 
 	down_read(&policy->rwsem);
 	cpus = cpumask_weight(policy->cpus);
@@ -1416,9 +1398,10 @@ static int __cpufreq_remove_dev_finish(struct device *dev,
 	unsigned long flags;
 	struct cpufreq_policy *policy;
 
-	read_lock_irqsave(&cpufreq_driver_lock, flags);
+	write_lock_irqsave(&cpufreq_driver_lock, flags);
 	policy = per_cpu(cpufreq_cpu_data, cpu);
-	read_unlock_irqrestore(&cpufreq_driver_lock, flags);
+	per_cpu(cpufreq_cpu_data, cpu) = NULL;
+	write_unlock_irqrestore(&cpufreq_driver_lock, flags);
 
 	if (!policy) {
 		pr_debug("%s: No cpu_data found\n", __func__);
@@ -1473,7 +1456,6 @@ static int __cpufreq_remove_dev_finish(struct device *dev,
 		}
 	}
 
-	per_cpu(cpufreq_cpu_data, cpu) = NULL;
 	return 0;
 }
 
@@ -1510,30 +1492,23 @@ static void handle_update(struct work_struct *work)
 /**
  *	cpufreq_out_of_sync - If actual and saved CPU frequency differs, we're
  *	in deep trouble.
- *	@cpu: cpu number
- *	@old_freq: CPU frequency the kernel thinks the CPU runs at
+ *	@policy: policy managing CPUs
  *	@new_freq: CPU frequency the CPU actually runs at
  *
  *	We adjust to current frequency first, and need to clean up later.
  *	So either call to cpufreq_update_policy() or schedule handle_update()).
  */
-static void cpufreq_out_of_sync(unsigned int cpu, unsigned int old_freq,
+static void cpufreq_out_of_sync(struct cpufreq_policy *policy,
 				unsigned int new_freq)
 {
-	struct cpufreq_policy *policy;
 	struct cpufreq_freqs freqs;
-	unsigned long flags;
 
 	pr_debug("Warning: CPU frequency out of sync: cpufreq and timing core thinks of %u, is %u kHz\n",
-		 old_freq, new_freq);
+		 policy->cur, new_freq);
 
-	freqs.old = old_freq;
+	freqs.old = policy->cur;
 	freqs.new = new_freq;
 
-	read_lock_irqsave(&cpufreq_driver_lock, flags);
-	policy = per_cpu(cpufreq_cpu_data, cpu);
-	read_unlock_irqrestore(&cpufreq_driver_lock, flags);
-
 	cpufreq_freq_transition_begin(policy, &freqs);
 	cpufreq_freq_transition_end(policy, &freqs, 0);
 }
@@ -1583,22 +1558,21 @@ unsigned int cpufreq_quick_get_max(unsigned int cpu)
 }
 EXPORT_SYMBOL(cpufreq_quick_get_max);
 
-static unsigned int __cpufreq_get(unsigned int cpu)
+static unsigned int __cpufreq_get(struct cpufreq_policy *policy)
 {
-	struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu);
 	unsigned int ret_freq = 0;
 
 	if (!cpufreq_driver->get)
 		return ret_freq;
 
-	ret_freq = cpufreq_driver->get(cpu);
+	ret_freq = cpufreq_driver->get(policy->cpu);
 
 	if (ret_freq && policy->cur &&
 		!(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS)) {
 		/* verify no discrepancy between actual and
 					saved value exists */
 		if (unlikely(ret_freq != policy->cur)) {
-			cpufreq_out_of_sync(cpu, policy->cur, ret_freq);
+			cpufreq_out_of_sync(policy, ret_freq);
 			schedule_work(&policy->update);
 		}
 	}
@@ -1619,7 +1593,7 @@ unsigned int cpufreq_get(unsigned int cpu)
 
 	if (policy) {
 		down_read(&policy->rwsem);
-		ret_freq = __cpufreq_get(cpu);
+		ret_freq = __cpufreq_get(policy);
 		up_read(&policy->rwsem);
 
 		cpufreq_cpu_put(policy);
@@ -1682,7 +1656,7 @@ void cpufreq_suspend(void)
 
 	pr_debug("%s: Suspending Governors\n", __func__);
 
-	list_for_each_entry(policy, &cpufreq_policy_list, policy_list) {
+	for_each_policy(policy) {
 		if (__cpufreq_governor(policy, CPUFREQ_GOV_STOP))
 			pr_err("%s: Failed to stop governor for policy: %p\n",
 				__func__, policy);
@@ -1716,7 +1690,7 @@ void cpufreq_resume(void)
 
 	pr_debug("%s: Resuming Governors\n", __func__);
 
-	list_for_each_entry(policy, &cpufreq_policy_list, policy_list) {
+	for_each_policy(policy) {
 		if (cpufreq_driver->resume && cpufreq_driver->resume(policy))
 			pr_err("%s: Failed to resume driver: %p\n", __func__,
 				policy);
@@ -2006,10 +1980,6 @@ int cpufreq_driver_target(struct cpufreq_policy *policy,
 }
 EXPORT_SYMBOL_GPL(cpufreq_driver_target);
 
-/*
- * when "event" is CPUFREQ_GOV_LIMITS
- */
-
 static int __cpufreq_governor(struct cpufreq_policy *policy,
 					unsigned int event)
 {
@@ -2107,7 +2077,7 @@ int cpufreq_register_governor(struct cpufreq_governor *governor)
 
 	governor->initialized = 0;
 	err = -EBUSY;
-	if (__find_governor(governor->name) == NULL) {
+	if (!find_governor(governor->name)) {
 		err = 0;
 		list_add(&governor->governor_list, &cpufreq_governor_list);
 	}
@@ -2307,8 +2277,7 @@ int cpufreq_update_policy(unsigned int cpu)
 			policy->cur = new_policy.cur;
 		} else {
 			if (policy->cur != new_policy.cur && has_target())
-				cpufreq_out_of_sync(cpu, policy->cur,
-								new_policy.cur);
+				cpufreq_out_of_sync(policy, new_policy.cur);
 		}
 	}
 
@@ -2364,7 +2333,7 @@ static int cpufreq_boost_set_sw(int state)
 	struct cpufreq_policy *policy;
 	int ret = -EINVAL;
 
-	list_for_each_entry(policy, &cpufreq_policy_list, policy_list) {
+	for_each_policy(policy) {
 		freq_table = cpufreq_frequency_get_table(policy->cpu);
 		if (freq_table) {
 			ret = cpufreq_frequency_table_cpuinfo(policy,
@@ -2454,9 +2423,6 @@ int cpufreq_register_driver(struct cpufreq_driver *driver_data)
 
 	pr_debug("trying to register driver %s\n", driver_data->name);
 
-	if (driver_data->setpolicy)
-		driver_data->flags |= CPUFREQ_CONST_LOOPS;
-
 	write_lock_irqsave(&cpufreq_driver_lock, flags);
 	if (cpufreq_driver) {
 		write_unlock_irqrestore(&cpufreq_driver_lock, flags);
@@ -2465,6 +2431,9 @@ int cpufreq_register_driver(struct cpufreq_driver *driver_data)
 	cpufreq_driver = driver_data;
 	write_unlock_irqrestore(&cpufreq_driver_lock, flags);
 
+	if (driver_data->setpolicy)
+		driver_data->flags |= CPUFREQ_CONST_LOOPS;
+
 	if (cpufreq_boost_supported()) {
 		/*
 		 * Check if driver provides function to enable boost -
@@ -2485,23 +2454,12 @@ int cpufreq_register_driver(struct cpufreq_driver *driver_data)
 	if (ret)
 		goto err_boost_unreg;
 
-	if (!(cpufreq_driver->flags & CPUFREQ_STICKY)) {
-		int i;
-		ret = -ENODEV;
-
-		/* check for at least one working CPU */
-		for (i = 0; i < nr_cpu_ids; i++)
-			if (cpu_possible(i) && per_cpu(cpufreq_cpu_data, i)) {
-				ret = 0;
-				break;
-			}
-
+	if (!(cpufreq_driver->flags & CPUFREQ_STICKY) &&
+	    list_empty(&cpufreq_policy_list)) {
 		/* if all ->init() calls failed, unregister */
-		if (ret) {
-			pr_debug("no CPU initialized for driver %s\n",
-				 driver_data->name);
-			goto err_if_unreg;
-		}
+		pr_debug("%s: No CPU initialized for driver %s\n", __func__,
+			 driver_data->name);
+		goto err_if_unreg;
 	}
 
 	register_hotcpu_notifier(&cpufreq_cpu_notifier);
@@ -2556,6 +2514,14 @@ int cpufreq_unregister_driver(struct cpufreq_driver *driver)
 }
 EXPORT_SYMBOL_GPL(cpufreq_unregister_driver);
 
+/*
+ * Stop cpufreq at shutdown to make sure it isn't holding any locks
+ * or mutexes when secondary CPUs are halted.
+ */
+static struct syscore_ops cpufreq_syscore_ops = {
+	.shutdown = cpufreq_suspend,
+};
+
 static int __init cpufreq_core_init(void)
 {
 	if (cpufreq_disabled())
@@ -2564,6 +2530,8 @@ static int __init cpufreq_core_init(void)
 	cpufreq_global_kobject = kobject_create();
 	BUG_ON(!cpufreq_global_kobject);
 
+	register_syscore_ops(&cpufreq_syscore_ops);
+
 	return 0;
 }
 core_initcall(cpufreq_core_init);
diff --git a/drivers/cpufreq/cpufreq_stats.c b/drivers/cpufreq/cpufreq_stats.c
index 0cd9b4dcef99..5e370a30a964 100644
--- a/drivers/cpufreq/cpufreq_stats.c
+++ b/drivers/cpufreq/cpufreq_stats.c
@@ -18,7 +18,6 @@
 static spinlock_t cpufreq_stats_lock;
 
 struct cpufreq_stats {
-	unsigned int cpu;
 	unsigned int total_trans;
 	unsigned long long last_time;
 	unsigned int max_state;
@@ -31,50 +30,33 @@ struct cpufreq_stats {
 #endif
 };
 
-static DEFINE_PER_CPU(struct cpufreq_stats *, cpufreq_stats_table);
-
-struct cpufreq_stats_attribute {
-	struct attribute attr;
-	ssize_t(*show) (struct cpufreq_stats *, char *);
-};
-
-static int cpufreq_stats_update(unsigned int cpu)
+static int cpufreq_stats_update(struct cpufreq_stats *stats)
 {
-	struct cpufreq_stats *stat;
-	unsigned long long cur_time;
+	unsigned long long cur_time = get_jiffies_64();
 
-	cur_time = get_jiffies_64();
 	spin_lock(&cpufreq_stats_lock);
-	stat = per_cpu(cpufreq_stats_table, cpu);
-	if (stat->time_in_state)
-		stat->time_in_state[stat->last_index] +=
-			cur_time - stat->last_time;
-	stat->last_time = cur_time;
+	stats->time_in_state[stats->last_index] += cur_time - stats->last_time;
+	stats->last_time = cur_time;
 	spin_unlock(&cpufreq_stats_lock);
 	return 0;
 }
 
 static ssize_t show_total_trans(struct cpufreq_policy *policy, char *buf)
 {
-	struct cpufreq_stats *stat = per_cpu(cpufreq_stats_table, policy->cpu);
-	if (!stat)
-		return 0;
-	return sprintf(buf, "%d\n",
-			per_cpu(cpufreq_stats_table, stat->cpu)->total_trans);
+	return sprintf(buf, "%d\n", policy->stats->total_trans);
 }
 
 static ssize_t show_time_in_state(struct cpufreq_policy *policy, char *buf)
 {
+	struct cpufreq_stats *stats = policy->stats;
 	ssize_t len = 0;
 	int i;
-	struct cpufreq_stats *stat = per_cpu(cpufreq_stats_table, policy->cpu);
-	if (!stat)
-		return 0;
-	cpufreq_stats_update(stat->cpu);
-	for (i = 0; i < stat->state_num; i++) {
-		len += sprintf(buf + len, "%u %llu\n", stat->freq_table[i],
+
+	cpufreq_stats_update(stats);
+	for (i = 0; i < stats->state_num; i++) {
+		len += sprintf(buf + len, "%u %llu\n", stats->freq_table[i],
 			(unsigned long long)
-			jiffies_64_to_clock_t(stat->time_in_state[i]));
+			jiffies_64_to_clock_t(stats->time_in_state[i]));
 	}
 	return len;
 }
@@ -82,38 +64,35 @@ static ssize_t show_time_in_state(struct cpufreq_policy *policy, char *buf)
 #ifdef CONFIG_CPU_FREQ_STAT_DETAILS
 static ssize_t show_trans_table(struct cpufreq_policy *policy, char *buf)
 {
+	struct cpufreq_stats *stats = policy->stats;
 	ssize_t len = 0;
 	int i, j;
 
-	struct cpufreq_stats *stat = per_cpu(cpufreq_stats_table, policy->cpu);
-	if (!stat)
-		return 0;
-	cpufreq_stats_update(stat->cpu);
 	len += snprintf(buf + len, PAGE_SIZE - len, "   From  :    To\n");
 	len += snprintf(buf + len, PAGE_SIZE - len, "         : ");
-	for (i = 0; i < stat->state_num; i++) {
+	for (i = 0; i < stats->state_num; i++) {
 		if (len >= PAGE_SIZE)
 			break;
 		len += snprintf(buf + len, PAGE_SIZE - len, "%9u ",
-				stat->freq_table[i]);
+				stats->freq_table[i]);
 	}
 	if (len >= PAGE_SIZE)
 		return PAGE_SIZE;
 
 	len += snprintf(buf + len, PAGE_SIZE - len, "\n");
 
-	for (i = 0; i < stat->state_num; i++) {
+	for (i = 0; i < stats->state_num; i++) {
 		if (len >= PAGE_SIZE)
 			break;
 
 		len += snprintf(buf + len, PAGE_SIZE - len, "%9u: ",
-				stat->freq_table[i]);
+				stats->freq_table[i]);
 
-		for (j = 0; j < stat->state_num; j++) {
+		for (j = 0; j < stats->state_num; j++) {
 			if (len >= PAGE_SIZE)
 				break;
 			len += snprintf(buf + len, PAGE_SIZE - len, "%9u ",
-					stat->trans_table[i*stat->max_state+j]);
+					stats->trans_table[i*stats->max_state+j]);
 		}
 		if (len >= PAGE_SIZE)
 			break;
@@ -142,28 +121,29 @@ static struct attribute_group stats_attr_group = {
 	.name = "stats"
 };
 
-static int freq_table_get_index(struct cpufreq_stats *stat, unsigned int freq)
+static int freq_table_get_index(struct cpufreq_stats *stats, unsigned int freq)
 {
 	int index;
-	for (index = 0; index < stat->max_state; index++)
-		if (stat->freq_table[index] == freq)
+	for (index = 0; index < stats->max_state; index++)
+		if (stats->freq_table[index] == freq)
 			return index;
 	return -1;
 }
 
 static void __cpufreq_stats_free_table(struct cpufreq_policy *policy)
 {
-	struct cpufreq_stats *stat = per_cpu(cpufreq_stats_table, policy->cpu);
+	struct cpufreq_stats *stats = policy->stats;
 
-	if (!stat)
+	/* Already freed */
+	if (!stats)
 		return;
 
-	pr_debug("%s: Free stat table\n", __func__);
+	pr_debug("%s: Free stats table\n", __func__);
 
 	sysfs_remove_group(&policy->kobj, &stats_attr_group);
-	kfree(stat->time_in_state);
-	kfree(stat);
-	per_cpu(cpufreq_stats_table, policy->cpu) = NULL;
+	kfree(stats->time_in_state);
+	kfree(stats);
+	policy->stats = NULL;
 }
 
 static void cpufreq_stats_free_table(unsigned int cpu)
@@ -174,37 +154,33 @@ static void cpufreq_stats_free_table(unsigned int cpu)
 	if (!policy)
 		return;
 
-	if (cpufreq_frequency_get_table(policy->cpu))
-		__cpufreq_stats_free_table(policy);
+	__cpufreq_stats_free_table(policy);
 
 	cpufreq_cpu_put(policy);
 }
 
 static int __cpufreq_stats_create_table(struct cpufreq_policy *policy)
 {
-	unsigned int i, count = 0, ret = 0;
-	struct cpufreq_stats *stat;
+	unsigned int i = 0, count = 0, ret = -ENOMEM;
+	struct cpufreq_stats *stats;
 	unsigned int alloc_size;
 	unsigned int cpu = policy->cpu;
 	struct cpufreq_frequency_table *pos, *table;
 
+	/* We need cpufreq table for creating stats table */
 	table = cpufreq_frequency_get_table(cpu);
 	if (unlikely(!table))
 		return 0;
 
-	if (per_cpu(cpufreq_stats_table, cpu))
-		return -EBUSY;
-	stat = kzalloc(sizeof(*stat), GFP_KERNEL);
-	if ((stat) == NULL)
-		return -ENOMEM;
-
-	ret = sysfs_create_group(&policy->kobj, &stats_attr_group);
-	if (ret)
-		goto error_out;
+	/* stats already initialized */
+	if (policy->stats)
+		return -EEXIST;
 
-	stat->cpu = cpu;
-	per_cpu(cpufreq_stats_table, cpu) = stat;
+	stats = kzalloc(sizeof(*stats), GFP_KERNEL);
+	if (!stats)
+		return -ENOMEM;
 
+	/* Find total allocation size */
 	cpufreq_for_each_valid_entry(pos, table)
 		count++;
 
@@ -213,32 +189,40 @@ static int __cpufreq_stats_create_table(struct cpufreq_policy *policy)
 #ifdef CONFIG_CPU_FREQ_STAT_DETAILS
 	alloc_size += count * count * sizeof(int);
 #endif
-	stat->max_state = count;
-	stat->time_in_state = kzalloc(alloc_size, GFP_KERNEL);
-	if (!stat->time_in_state) {
-		ret = -ENOMEM;
-		goto error_alloc;
-	}
-	stat->freq_table = (unsigned int *)(stat->time_in_state + count);
+
+	/* Allocate memory for time_in_state/freq_table/trans_table in one go */
+	stats->time_in_state = kzalloc(alloc_size, GFP_KERNEL);
+	if (!stats->time_in_state)
+		goto free_stat;
+
+	stats->freq_table = (unsigned int *)(stats->time_in_state + count);
 
 #ifdef CONFIG_CPU_FREQ_STAT_DETAILS
-	stat->trans_table = stat->freq_table + count;
+	stats->trans_table = stats->freq_table + count;
 #endif
-	i = 0;
+
+	stats->max_state = count;
+
+	/* Find valid-unique entries */
 	cpufreq_for_each_valid_entry(pos, table)
-		if (freq_table_get_index(stat, pos->frequency) == -1)
-			stat->freq_table[i++] = pos->frequency;
-	stat->state_num = i;
-	spin_lock(&cpufreq_stats_lock);
-	stat->last_time = get_jiffies_64();
-	stat->last_index = freq_table_get_index(stat, policy->cur);
-	spin_unlock(&cpufreq_stats_lock);
-	return 0;
-error_alloc:
-	sysfs_remove_group(&policy->kobj, &stats_attr_group);
-error_out:
-	kfree(stat);
-	per_cpu(cpufreq_stats_table, cpu) = NULL;
+		if (freq_table_get_index(stats, pos->frequency) == -1)
+			stats->freq_table[i++] = pos->frequency;
+
+	stats->state_num = i;
+	stats->last_time = get_jiffies_64();
+	stats->last_index = freq_table_get_index(stats, policy->cur);
+
+	policy->stats = stats;
+	ret = sysfs_create_group(&policy->kobj, &stats_attr_group);
+	if (!ret)
+		return 0;
+
+	/* We failed, release resources */
+	policy->stats = NULL;
+	kfree(stats->time_in_state);
+free_stat:
+	kfree(stats);
+
 	return ret;
 }
 
@@ -259,30 +243,12 @@ static void cpufreq_stats_create_table(unsigned int cpu)
 	cpufreq_cpu_put(policy);
 }
 
-static void cpufreq_stats_update_policy_cpu(struct cpufreq_policy *policy)
-{
-	struct cpufreq_stats *stat = per_cpu(cpufreq_stats_table,
-			policy->last_cpu);
-
-	pr_debug("Updating stats_table for new_cpu %u from last_cpu %u\n",
-			policy->cpu, policy->last_cpu);
-	per_cpu(cpufreq_stats_table, policy->cpu) = per_cpu(cpufreq_stats_table,
-			policy->last_cpu);
-	per_cpu(cpufreq_stats_table, policy->last_cpu) = NULL;
-	stat->cpu = policy->cpu;
-}
-
 static int cpufreq_stat_notifier_policy(struct notifier_block *nb,
 		unsigned long val, void *data)
 {
 	int ret = 0;
 	struct cpufreq_policy *policy = data;
 
-	if (val == CPUFREQ_UPDATE_POLICY_CPU) {
-		cpufreq_stats_update_policy_cpu(policy);
-		return 0;
-	}
-
 	if (val == CPUFREQ_CREATE_POLICY)
 		ret = __cpufreq_stats_create_table(policy);
 	else if (val == CPUFREQ_REMOVE_POLICY)
@@ -295,35 +261,45 @@ static int cpufreq_stat_notifier_trans(struct notifier_block *nb,
 		unsigned long val, void *data)
 {
 	struct cpufreq_freqs *freq = data;
-	struct cpufreq_stats *stat;
+	struct cpufreq_policy *policy = cpufreq_cpu_get(freq->cpu);
+	struct cpufreq_stats *stats;
 	int old_index, new_index;
 
-	if (val != CPUFREQ_POSTCHANGE)
+	if (!policy) {
+		pr_err("%s: No policy found\n", __func__);
 		return 0;
+	}
 
-	stat = per_cpu(cpufreq_stats_table, freq->cpu);
-	if (!stat)
-		return 0;
+	if (val != CPUFREQ_POSTCHANGE)
+		goto put_policy;
 
-	old_index = stat->last_index;
-	new_index = freq_table_get_index(stat, freq->new);
+	if (!policy->stats) {
+		pr_debug("%s: No stats found\n", __func__);
+		goto put_policy;
+	}
 
-	/* We can't do stat->time_in_state[-1]= .. */
-	if (old_index == -1 || new_index == -1)
-		return 0;
+	stats = policy->stats;
+
+	old_index = stats->last_index;
+	new_index = freq_table_get_index(stats, freq->new);
 
-	cpufreq_stats_update(freq->cpu);
+	/* We can't do stats->time_in_state[-1]= .. */
+	if (old_index == -1 || new_index == -1)
+		goto put_policy;
 
 	if (old_index == new_index)
-		return 0;
+		goto put_policy;
 
-	spin_lock(&cpufreq_stats_lock);
-	stat->last_index = new_index;
+	cpufreq_stats_update(stats);
+
+	stats->last_index = new_index;
 #ifdef CONFIG_CPU_FREQ_STAT_DETAILS
-	stat->trans_table[old_index * stat->max_state + new_index]++;
+	stats->trans_table[old_index * stats->max_state + new_index]++;
 #endif
-	stat->total_trans++;
-	spin_unlock(&cpufreq_stats_lock);
+	stats->total_trans++;
+
+put_policy:
+	cpufreq_cpu_put(policy);
 	return 0;
 }
 
@@ -374,8 +350,7 @@ static void __exit cpufreq_stats_exit(void)
 }
 
 MODULE_AUTHOR("Zou Nan hai <nanhai.zou@intel.com>");
-MODULE_DESCRIPTION("'cpufreq_stats' - A driver to export cpufreq stats "
-				"through sysfs filesystem");
+MODULE_DESCRIPTION("Export cpufreq stats via sysfs");
 MODULE_LICENSE("GPL");
 
 module_init(cpufreq_stats_init);
diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c
index 742eefba12c2..872c5772c5d3 100644
--- a/drivers/cpufreq/intel_pstate.c
+++ b/drivers/cpufreq/intel_pstate.c
@@ -148,6 +148,8 @@ struct perf_limits {
 	int32_t min_perf;
 	int max_policy_pct;
 	int max_sysfs_pct;
+	int min_policy_pct;
+	int min_sysfs_pct;
 };
 
 static struct perf_limits limits = {
@@ -159,6 +161,8 @@ static struct perf_limits limits = {
 	.min_perf = 0,
 	.max_policy_pct = 100,
 	.max_sysfs_pct = 100,
+	.min_policy_pct = 0,
+	.min_sysfs_pct = 0,
 };
 
 static inline void pid_reset(struct _pid *pid, int setpoint, int busy,
@@ -338,6 +342,33 @@ static void __init intel_pstate_debug_expose_params(void)
 		return sprintf(buf, "%u\n", limits.object);		\
 	}
 
+static ssize_t show_turbo_pct(struct kobject *kobj,
+				struct attribute *attr, char *buf)
+{
+	struct cpudata *cpu;
+	int total, no_turbo, turbo_pct;
+	uint32_t turbo_fp;
+
+	cpu = all_cpu_data[0];
+
+	total = cpu->pstate.turbo_pstate - cpu->pstate.min_pstate + 1;
+	no_turbo = cpu->pstate.max_pstate - cpu->pstate.min_pstate + 1;
+	turbo_fp = div_fp(int_tofp(no_turbo), int_tofp(total));
+	turbo_pct = 100 - fp_toint(mul_fp(turbo_fp, int_tofp(100)));
+	return sprintf(buf, "%u\n", turbo_pct);
+}
+
+static ssize_t show_num_pstates(struct kobject *kobj,
+				struct attribute *attr, char *buf)
+{
+	struct cpudata *cpu;
+	int total;
+
+	cpu = all_cpu_data[0];
+	total = cpu->pstate.turbo_pstate - cpu->pstate.min_pstate + 1;
+	return sprintf(buf, "%u\n", total);
+}
+
 static ssize_t show_no_turbo(struct kobject *kobj,
 			     struct attribute *attr, char *buf)
 {
@@ -404,7 +435,9 @@ static ssize_t store_min_perf_pct(struct kobject *a, struct attribute *b,
 	ret = sscanf(buf, "%u", &input);
 	if (ret != 1)
 		return -EINVAL;
-	limits.min_perf_pct = clamp_t(int, input, 0 , 100);
+
+	limits.min_sysfs_pct = clamp_t(int, input, 0 , 100);
+	limits.min_perf_pct = max(limits.min_policy_pct, limits.min_sysfs_pct);
 	limits.min_perf = div_fp(int_tofp(limits.min_perf_pct), int_tofp(100));
 
 	if (hwp_active)
@@ -418,11 +451,15 @@ show_one(min_perf_pct, min_perf_pct);
 define_one_global_rw(no_turbo);
 define_one_global_rw(max_perf_pct);
 define_one_global_rw(min_perf_pct);
+define_one_global_ro(turbo_pct);
+define_one_global_ro(num_pstates);
 
 static struct attribute *intel_pstate_attributes[] = {
 	&no_turbo.attr,
 	&max_perf_pct.attr,
 	&min_perf_pct.attr,
+	&turbo_pct.attr,
+	&num_pstates.attr,
 	NULL
 };
 
@@ -825,6 +862,7 @@ static const struct x86_cpu_id intel_pstate_cpu_ids[] = {
 	ICPU(0x46, core_params),
 	ICPU(0x47, core_params),
 	ICPU(0x4c, byt_params),
+	ICPU(0x4e, core_params),
 	ICPU(0x4f, core_params),
 	ICPU(0x56, core_params),
 	{}
@@ -887,7 +925,9 @@ static int intel_pstate_set_policy(struct cpufreq_policy *policy)
 	if (!policy->cpuinfo.max_freq)
 		return -ENODEV;
 
-	if (policy->policy == CPUFREQ_POLICY_PERFORMANCE) {
+	if (policy->policy == CPUFREQ_POLICY_PERFORMANCE &&
+	    policy->max >= policy->cpuinfo.max_freq) {
+		limits.min_policy_pct = 100;
 		limits.min_perf_pct = 100;
 		limits.min_perf = int_tofp(1);
 		limits.max_policy_pct = 100;
@@ -897,8 +937,9 @@ static int intel_pstate_set_policy(struct cpufreq_policy *policy)
 		return 0;
 	}
 
-	limits.min_perf_pct = (policy->min * 100) / policy->cpuinfo.max_freq;
-	limits.min_perf_pct = clamp_t(int, limits.min_perf_pct, 0 , 100);
+	limits.min_policy_pct = (policy->min * 100) / policy->cpuinfo.max_freq;
+	limits.min_policy_pct = clamp_t(int, limits.min_policy_pct, 0 , 100);
+	limits.min_perf_pct = max(limits.min_policy_pct, limits.min_sysfs_pct);
 	limits.min_perf = div_fp(int_tofp(limits.min_perf_pct), int_tofp(100));
 
 	limits.max_policy_pct = (policy->max * 100) / policy->cpuinfo.max_freq;
@@ -978,6 +1019,7 @@ static struct cpufreq_driver intel_pstate_driver = {
 
 static int __initdata no_load;
 static int __initdata no_hwp;
+static int __initdata hwp_only;
 static unsigned int force_load;
 
 static int intel_pstate_msrs_not_valid(void)
@@ -1175,6 +1217,9 @@ static int __init intel_pstate_init(void)
 	if (cpu_has(c,X86_FEATURE_HWP) && !no_hwp)
 		intel_pstate_hwp_enable();
 
+	if (!hwp_active && hwp_only)
+		goto out;
+
 	rc = cpufreq_register_driver(&intel_pstate_driver);
 	if (rc)
 		goto out;
@@ -1209,6 +1254,8 @@ static int __init intel_pstate_setup(char *str)
 		no_hwp = 1;
 	if (!strcmp(str, "force"))
 		force_load = 1;
+	if (!strcmp(str, "hwp_only"))
+		hwp_only = 1;
 	return 0;
 }
 early_param("intel_pstate", intel_pstate_setup);
diff --git a/drivers/cpufreq/ls1x-cpufreq.c b/drivers/cpufreq/ls1x-cpufreq.c
index 25fbd6a1374f..f0913eee2f50 100644
--- a/drivers/cpufreq/ls1x-cpufreq.c
+++ b/drivers/cpufreq/ls1x-cpufreq.c
@@ -210,7 +210,6 @@ out:
 static struct platform_driver ls1x_cpufreq_platdrv = {
 	.driver = {
 		.name	= "ls1x-cpufreq",
-		.owner	= THIS_MODULE,
 	},
 	.probe		= ls1x_cpufreq_probe,
 	.remove		= ls1x_cpufreq_remove,
diff --git a/drivers/cpufreq/sfi-cpufreq.c b/drivers/cpufreq/sfi-cpufreq.c
new file mode 100644
index 000000000000..ffa3389e535b
--- /dev/null
+++ b/drivers/cpufreq/sfi-cpufreq.c
@@ -0,0 +1,136 @@
+/*
+ *  SFI Performance States Driver
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License.
+ *
+ *  This program is distributed in the hope that it will be useful, but
+ *  WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ *  General Public License for more details.
+ *
+ *  Author: Vishwesh M Rudramuni <vishwesh.m.rudramuni@intel.com>
+ *  Author: Srinidhi Kasagar <srinidhi.kasagar@intel.com>
+ */
+
+#include <linux/cpufreq.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/sfi.h>
+#include <linux/slab.h>
+#include <linux/smp.h>
+
+#include <asm/msr.h>
+
+struct cpufreq_frequency_table *freq_table;
+static struct sfi_freq_table_entry *sfi_cpufreq_array;
+static int num_freq_table_entries;
+
+static int sfi_parse_freq(struct sfi_table_header *table)
+{
+	struct sfi_table_simple *sb;
+	struct sfi_freq_table_entry *pentry;
+	int totallen;
+
+	sb = (struct sfi_table_simple *)table;
+	num_freq_table_entries = SFI_GET_NUM_ENTRIES(sb,
+			struct sfi_freq_table_entry);
+	if (num_freq_table_entries <= 1) {
+		pr_err("No p-states discovered\n");
+		return -ENODEV;
+	}
+
+	pentry = (struct sfi_freq_table_entry *)sb->pentry;
+	totallen = num_freq_table_entries * sizeof(*pentry);
+
+	sfi_cpufreq_array = kzalloc(totallen, GFP_KERNEL);
+	if (!sfi_cpufreq_array)
+		return -ENOMEM;
+
+	memcpy(sfi_cpufreq_array, pentry, totallen);
+
+	return 0;
+}
+
+static int sfi_cpufreq_target(struct cpufreq_policy *policy, unsigned int index)
+{
+	unsigned int next_perf_state = 0; /* Index into perf table */
+	u32 lo, hi;
+
+	next_perf_state = policy->freq_table[index].driver_data;
+
+	rdmsr_on_cpu(policy->cpu, MSR_IA32_PERF_CTL, &lo, &hi);
+	lo = (lo & ~INTEL_PERF_CTL_MASK) |
+		((u32) sfi_cpufreq_array[next_perf_state].ctrl_val &
+		INTEL_PERF_CTL_MASK);
+	wrmsr_on_cpu(policy->cpu, MSR_IA32_PERF_CTL, lo, hi);
+
+	return 0;
+}
+
+static int sfi_cpufreq_cpu_init(struct cpufreq_policy *policy)
+{
+	policy->shared_type = CPUFREQ_SHARED_TYPE_HW;
+	policy->cpuinfo.transition_latency = 100000;	/* 100us */
+
+	return cpufreq_table_validate_and_show(policy, freq_table);
+}
+
+static struct cpufreq_driver sfi_cpufreq_driver = {
+	.flags		= CPUFREQ_CONST_LOOPS,
+	.verify		= cpufreq_generic_frequency_table_verify,
+	.target_index	= sfi_cpufreq_target,
+	.init		= sfi_cpufreq_cpu_init,
+	.name		= "sfi-cpufreq",
+	.attr		= cpufreq_generic_attr,
+};
+
+static int __init sfi_cpufreq_init(void)
+{
+	int ret, i;
+
+	/* parse the freq table from SFI */
+	ret = sfi_table_parse(SFI_SIG_FREQ, NULL, NULL, sfi_parse_freq);
+	if (ret)
+		return ret;
+
+	freq_table = kzalloc(sizeof(*freq_table) *
+			(num_freq_table_entries + 1), GFP_KERNEL);
+	if (!freq_table) {
+		ret = -ENOMEM;
+		goto err_free_array;
+	}
+
+	for (i = 0; i < num_freq_table_entries; i++) {
+		freq_table[i].driver_data = i;
+		freq_table[i].frequency = sfi_cpufreq_array[i].freq_mhz * 1000;
+	}
+	freq_table[i].frequency = CPUFREQ_TABLE_END;
+
+	ret = cpufreq_register_driver(&sfi_cpufreq_driver);
+	if (ret)
+		goto err_free_tbl;
+
+	return ret;
+
+err_free_tbl:
+	kfree(freq_table);
+err_free_array:
+	kfree(sfi_cpufreq_array);
+	return ret;
+}
+late_initcall(sfi_cpufreq_init);
+
+static void __exit sfi_cpufreq_exit(void)
+{
+	cpufreq_unregister_driver(&sfi_cpufreq_driver);
+	kfree(freq_table);
+	kfree(sfi_cpufreq_array);
+}
+module_exit(sfi_cpufreq_exit);
+
+MODULE_AUTHOR("Vishwesh M Rudramuni <vishwesh.m.rudramuni@intel.com>");
+MODULE_DESCRIPTION("SFI Performance-States Driver");
+MODULE_LICENSE("GPL");