Merge tag 'pm-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management updates from Rafael Wysocki:
 "These add support for 'artificial' Energy Models in which power
  numbers for different entities may be in different scales, add support
  for some new hardware, fix bugs and clean up code in multiple places.

  Specifics:

   - Update the Energy Model support code to allow the Energy Model to
     be artificial, which means that the power values may not be on a
     uniform scale with other devices providing power information, and
     update the cpufreq_cooling and devfreq_cooling thermal drivers to
     support artificial Energy Models (Lukasz Luba).

   - Make DTPM check the Energy Model type (Lukasz Luba).

   - Fix policy counter decrementation in cpufreq if Energy Model is in
     use (Pierre Gondois).

   - Add CPU-based scaling support to passive devfreq governor (Saravana
     Kannan, Chanwoo Choi).

   - Update the rk3399_dmc devfreq driver (Brian Norris).

   - Export dev_pm_ops instead of suspend() and resume() in the IIO
     chemical scd30 driver (Jonathan Cameron).

   - Add namespace variants of EXPORT[_GPL]_SIMPLE_DEV_PM_OPS and
     PM-runtime counterparts (Jonathan Cameron).

   - Move symbol exports in the IIO chemical scd30 driver into the
     IIO_SCD30 namespace (Jonathan Cameron).

   - Avoid device PM-runtime usage count underflows (Rafael Wysocki).

   - Allow dynamic debug to control printing of PM messages (David
     Cohen).

   - Fix some kernel-doc comments in hibernation code (Yang Li, Haowen
     Bai).

   - Preserve ACPI-table override during hibernation (Amadeusz
     Sławiński).

   - Improve support for suspend-to-RAM for PSCI OSI mode (Ulf Hansson).

   - Make Intel RAPL power capping driver support the RaptorLake and
     AlderLake N processors (Zhang Rui, Sumeet Pawnikar).

   - Remove redundant store to value after multiply in the RAPL power
     capping driver (Colin Ian King).

   - Add AlderLake processor support to the intel_idle driver (Zhang
     Rui).

   - Fix regression leading to no genpd governor in the PSCI cpuidle
     driver and fix the riscv-sbi cpuidle driver to allow a genpd
     governor to be used (Ulf Hansson).

   - Fix cpufreq governor clean up code to avoid using kfree() directly
     to free kobject-based items (Kevin Hao).

   - Prepare cpufreq for powerpc's asm/prom.h cleanup (Christophe
     Leroy).

   - Make intel_pstate notify frequency invariance code when no_turbo is
     turned on and off (Chen Yu).

   - Add Sapphire Rapids OOB mode support to intel_pstate (Srinivas
     Pandruvada).

   - Make cpufreq avoid unnecessary frequency updates due to mismatch
     between hardware and the frequency table (Viresh Kumar).

   - Make remove_cpu_dev_symlink() clear the real_cpus mask to simplify
     code (Viresh Kumar).

   - Rearrange cpufreq_offline() and cpufreq_remove_dev() to make the
     calling convention for some driver callbacks consistent (Rafael
     Wysocki).

   - Avoid accessing half-initialized cpufreq policies from the show()
     and store() sysfs functions (Schspa Shi).

   - Rearrange cpufreq_offline() to make the calling convention for some
     driver callbacks consistent (Schspa Shi).

   - Update CPPC handling in cpufreq (Pierre Gondois).

   - Extend dev_pm_domain_detach() doc (Krzysztof Kozlowski).

   - Move genpd's time-accounting to ktime_get_mono_fast_ns() (Ulf
     Hansson).

   - Improve the way genpd deals with its governors (Ulf Hansson).

   - Update the turbostat utility to version 2022.04.16 (Len Brown, Dan
     Merillat, Sumeet Pawnikar, Zephaniah E. Loss-Cutler-Hull, Chen Yu)"

* tag 'pm-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (94 commits)
  PM: domains: Trust domain-idle-states from DT to be correct by genpd
  PM: domains: Measure power-on/off latencies in genpd based on a governor
  PM: domains: Allocate governor data dynamically based on a genpd governor
  PM: domains: Clean up some code in pm_genpd_init() and genpd_remove()
  PM: domains: Fix initialization of genpd's next_wakeup
  PM: domains: Fixup QoS latency measurements for IRQ safe devices in genpd
  PM: domains: Measure suspend/resume latencies in genpd based on governor
  PM: domains: Move the next_wakeup variable into the struct gpd_timing_data
  PM: domains: Allocate gpd_timing_data dynamically based on governor
  PM: domains: Skip another warning in irq_safe_dev_in_sleep_domain()
  PM: domains: Rename irq_safe_dev_in_no_sleep_domain() in genpd
  PM: domains: Don't check PM_QOS_FLAG_NO_POWER_OFF in genpd
  PM: domains: Drop redundant code for genpd always-on governor
  PM: domains: Add GENPD_FLAG_RPM_ALWAYS_ON for the always-on governor
  powercap: intel_rapl: remove redundant store to value after multiply
  cpufreq: CPPC: Enable dvfs_possible_from_any_cpu
  cpufreq: CPPC: Enable fast_switch
  ACPI: CPPC: Assume no transition latency if no PCCT
  ACPI: bus: Set CPPC _OSC bits for all and when CPPC_LIB is supported
  ACPI: CPPC: Check _OSC for flexible address space
  ...

4 files changed, 251 insertions, 153 deletions

diff --git a/drivers/base/power/common.c b/drivers/base/power/common.c
index bbddb267c2e6..72115917e0bd 100644
--- a/drivers/base/power/common.c
+++ b/drivers/base/power/common.c
@@ -172,10 +172,10 @@ EXPORT_SYMBOL_GPL(dev_pm_domain_attach_by_name);
  * @dev: Device to detach.
  * @power_off: Used to indicate whether we should power off the device.
  *
- * This functions will reverse the actions from dev_pm_domain_attach() and
- * dev_pm_domain_attach_by_id(), thus it detaches @dev from its PM domain.
- * Typically it should be invoked during the remove phase, either from
- * subsystem level code or from drivers.
+ * This functions will reverse the actions from dev_pm_domain_attach(),
+ * dev_pm_domain_attach_by_id() and dev_pm_domain_attach_by_name(), thus it
+ * detaches @dev from its PM domain.  Typically it should be invoked during the
+ * remove phase, either from subsystem level code or from drivers.
  *
  * Callers must ensure proper synchronization of this function with power
  * management callbacks.
diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
index 1ee878d126fd..739e52cd4aba 100644
--- a/drivers/base/power/domain.c
+++ b/drivers/base/power/domain.c
@@ -131,7 +131,7 @@ static const struct genpd_lock_ops genpd_spin_ops = {
 #define genpd_is_cpu_domain(genpd)	(genpd->flags & GENPD_FLAG_CPU_DOMAIN)
 #define genpd_is_rpm_always_on(genpd)	(genpd->flags & GENPD_FLAG_RPM_ALWAYS_ON)
 
-static inline bool irq_safe_dev_in_no_sleep_domain(struct device *dev,
+static inline bool irq_safe_dev_in_sleep_domain(struct device *dev,
 		const struct generic_pm_domain *genpd)
 {
 	bool ret;
@@ -139,11 +139,14 @@ static inline bool irq_safe_dev_in_no_sleep_domain(struct device *dev,
 	ret = pm_runtime_is_irq_safe(dev) && !genpd_is_irq_safe(genpd);
 
 	/*
-	 * Warn once if an IRQ safe device is attached to a no sleep domain, as
-	 * to indicate a suboptimal configuration for PM. For an always on
-	 * domain this isn't case, thus don't warn.
+	 * Warn once if an IRQ safe device is attached to a domain, which
+	 * callbacks are allowed to sleep. This indicates a suboptimal
+	 * configuration for PM, but it doesn't matter for an always on domain.
 	 */
-	if (ret && !genpd_is_always_on(genpd))
+	if (genpd_is_always_on(genpd) || genpd_is_rpm_always_on(genpd))
+		return ret;
+
+	if (ret)
 		dev_warn_once(dev, "PM domain %s will not be powered off\n",
 				genpd->name);
 
@@ -225,24 +228,23 @@ static void genpd_debug_remove(struct generic_pm_domain *genpd)
 
 static void genpd_update_accounting(struct generic_pm_domain *genpd)
 {
-	ktime_t delta, now;
+	u64 delta, now;
 
-	now = ktime_get();
-	delta = ktime_sub(now, genpd->accounting_time);
+	now = ktime_get_mono_fast_ns();
+	if (now <= genpd->accounting_time)
+		return;
+
+	delta = now - genpd->accounting_time;
 
 	/*
 	 * If genpd->status is active, it means we are just
 	 * out of off and so update the idle time and vice
 	 * versa.
 	 */
-	if (genpd->status == GENPD_STATE_ON) {
-		int state_idx = genpd->state_idx;
-
-		genpd->states[state_idx].idle_time =
-			ktime_add(genpd->states[state_idx].idle_time, delta);
-	} else {
-		genpd->on_time = ktime_add(genpd->on_time, delta);
-	}
+	if (genpd->status == GENPD_STATE_ON)
+		genpd->states[genpd->state_idx].idle_time += delta;
+	else
+		genpd->on_time += delta;
 
 	genpd->accounting_time = now;
 }
@@ -476,15 +478,16 @@ EXPORT_SYMBOL_GPL(dev_pm_genpd_set_performance_state);
  */
 void dev_pm_genpd_set_next_wakeup(struct device *dev, ktime_t next)
 {
-	struct generic_pm_domain_data *gpd_data;
 	struct generic_pm_domain *genpd;
+	struct gpd_timing_data *td;
 
 	genpd = dev_to_genpd_safe(dev);
 	if (!genpd)
 		return;
 
-	gpd_data = to_gpd_data(dev->power.subsys_data->domain_data);
-	gpd_data->next_wakeup = next;
+	td = to_gpd_data(dev->power.subsys_data->domain_data)->td;
+	if (td)
+		td->next_wakeup = next;
 }
 EXPORT_SYMBOL_GPL(dev_pm_genpd_set_next_wakeup);
 
@@ -506,6 +509,7 @@ static int _genpd_power_on(struct generic_pm_domain *genpd, bool timed)
 	if (!genpd->power_on)
 		goto out;
 
+	timed = timed && genpd->gd && !genpd->states[state_idx].fwnode;
 	if (!timed) {
 		ret = genpd->power_on(genpd);
 		if (ret)
@@ -524,7 +528,7 @@ static int _genpd_power_on(struct generic_pm_domain *genpd, bool timed)
 		goto out;
 
 	genpd->states[state_idx].power_on_latency_ns = elapsed_ns;
-	genpd->max_off_time_changed = true;
+	genpd->gd->max_off_time_changed = true;
 	pr_debug("%s: Power-%s latency exceeded, new value %lld ns\n",
 		 genpd->name, "on", elapsed_ns);
 
@@ -555,6 +559,7 @@ static int _genpd_power_off(struct generic_pm_domain *genpd, bool timed)
 	if (!genpd->power_off)
 		goto out;
 
+	timed = timed && genpd->gd && !genpd->states[state_idx].fwnode;
 	if (!timed) {
 		ret = genpd->power_off(genpd);
 		if (ret)
@@ -573,7 +578,7 @@ static int _genpd_power_off(struct generic_pm_domain *genpd, bool timed)
 		goto out;
 
 	genpd->states[state_idx].power_off_latency_ns = elapsed_ns;
-	genpd->max_off_time_changed = true;
+	genpd->gd->max_off_time_changed = true;
 	pr_debug("%s: Power-%s latency exceeded, new value %lld ns\n",
 		 genpd->name, "off", elapsed_ns);
 
@@ -649,18 +654,12 @@ static int genpd_power_off(struct generic_pm_domain *genpd, bool one_dev_on,
 	}
 
 	list_for_each_entry(pdd, &genpd->dev_list, list_node) {
-		enum pm_qos_flags_status stat;
-
-		stat = dev_pm_qos_flags(pdd->dev, PM_QOS_FLAG_NO_POWER_OFF);
-		if (stat > PM_QOS_FLAGS_NONE)
-			return -EBUSY;
-
 		/*
 		 * Do not allow PM domain to be powered off, when an IRQ safe
 		 * device is part of a non-IRQ safe domain.
 		 */
 		if (!pm_runtime_suspended(pdd->dev) ||
-			irq_safe_dev_in_no_sleep_domain(pdd->dev, genpd))
+			irq_safe_dev_in_sleep_domain(pdd->dev, genpd))
 			not_suspended++;
 	}
 
@@ -775,25 +774,27 @@ static int genpd_dev_pm_qos_notifier(struct notifier_block *nb,
 	dev = gpd_data->base.dev;
 
 	for (;;) {
-		struct generic_pm_domain *genpd;
+		struct generic_pm_domain *genpd = ERR_PTR(-ENODATA);
 		struct pm_domain_data *pdd;
+		struct gpd_timing_data *td;
 
 		spin_lock_irq(&dev->power.lock);
 
 		pdd = dev->power.subsys_data ?
 				dev->power.subsys_data->domain_data : NULL;
 		if (pdd) {
-			to_gpd_data(pdd)->td.constraint_changed = true;
-			genpd = dev_to_genpd(dev);
-		} else {
-			genpd = ERR_PTR(-ENODATA);
+			td = to_gpd_data(pdd)->td;
+			if (td) {
+				td->constraint_changed = true;
+				genpd = dev_to_genpd(dev);
+			}
 		}
 
 		spin_unlock_irq(&dev->power.lock);
 
 		if (!IS_ERR(genpd)) {
 			genpd_lock(genpd);
-			genpd->max_off_time_changed = true;
+			genpd->gd->max_off_time_changed = true;
 			genpd_unlock(genpd);
 		}
 
@@ -879,9 +880,9 @@ static int genpd_runtime_suspend(struct device *dev)
 	struct generic_pm_domain *genpd;
 	bool (*suspend_ok)(struct device *__dev);
 	struct generic_pm_domain_data *gpd_data = dev_gpd_data(dev);
-	struct gpd_timing_data *td = &gpd_data->td;
+	struct gpd_timing_data *td = gpd_data->td;
 	bool runtime_pm = pm_runtime_enabled(dev);
-	ktime_t time_start;
+	ktime_t time_start = 0;
 	s64 elapsed_ns;
 	int ret;
 
@@ -902,8 +903,7 @@ static int genpd_runtime_suspend(struct device *dev)
 		return -EBUSY;
 
 	/* Measure suspend latency. */
-	time_start = 0;
-	if (runtime_pm)
+	if (td && runtime_pm)
 		time_start = ktime_get();
 
 	ret = __genpd_runtime_suspend(dev);
@@ -917,13 +917,13 @@ static int genpd_runtime_suspend(struct device *dev)
 	}
 
 	/* Update suspend latency value if the measured time exceeds it. */
-	if (runtime_pm) {
+	if (td && runtime_pm) {
 		elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
 		if (elapsed_ns > td->suspend_latency_ns) {
 			td->suspend_latency_ns = elapsed_ns;
 			dev_dbg(dev, "suspend latency exceeded, %lld ns\n",
 				elapsed_ns);
-			genpd->max_off_time_changed = true;
+			genpd->gd->max_off_time_changed = true;
 			td->constraint_changed = true;
 		}
 	}
@@ -932,7 +932,7 @@ static int genpd_runtime_suspend(struct device *dev)
 	 * If power.irq_safe is set, this routine may be run with
 	 * IRQs disabled, so suspend only if the PM domain also is irq_safe.
 	 */
-	if (irq_safe_dev_in_no_sleep_domain(dev, genpd))
+	if (irq_safe_dev_in_sleep_domain(dev, genpd))
 		return 0;
 
 	genpd_lock(genpd);
@@ -955,12 +955,11 @@ static int genpd_runtime_resume(struct device *dev)
 {
 	struct generic_pm_domain *genpd;
 	struct generic_pm_domain_data *gpd_data = dev_gpd_data(dev);
-	struct gpd_timing_data *td = &gpd_data->td;
-	bool runtime_pm = pm_runtime_enabled(dev);
-	ktime_t time_start;
+	struct gpd_timing_data *td = gpd_data->td;
+	bool timed = td && pm_runtime_enabled(dev);
+	ktime_t time_start = 0;
 	s64 elapsed_ns;
 	int ret;
-	bool timed = true;
 
 	dev_dbg(dev, "%s()\n", __func__);
 
@@ -972,10 +971,8 @@ static int genpd_runtime_resume(struct device *dev)
 	 * As we don't power off a non IRQ safe domain, which holds
 	 * an IRQ safe device, we don't need to restore power to it.
 	 */
-	if (irq_safe_dev_in_no_sleep_domain(dev, genpd)) {
-		timed = false;
+	if (irq_safe_dev_in_sleep_domain(dev, genpd))
 		goto out;
-	}
 
 	genpd_lock(genpd);
 	ret = genpd_power_on(genpd, 0);
@@ -988,8 +985,7 @@ static int genpd_runtime_resume(struct device *dev)
 
  out:
 	/* Measure resume latency. */
-	time_start = 0;
-	if (timed && runtime_pm)
+	if (timed)
 		time_start = ktime_get();
 
 	ret = genpd_start_dev(genpd, dev);
@@ -1001,13 +997,13 @@ static int genpd_runtime_resume(struct device *dev)
 		goto err_stop;
 
 	/* Update resume latency value if the measured time exceeds it. */
-	if (timed && runtime_pm) {
+	if (timed) {
 		elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
 		if (elapsed_ns > td->resume_latency_ns) {
 			td->resume_latency_ns = elapsed_ns;
 			dev_dbg(dev, "resume latency exceeded, %lld ns\n",
 				elapsed_ns);
-			genpd->max_off_time_changed = true;
+			genpd->gd->max_off_time_changed = true;
 			td->constraint_changed = true;
 		}
 	}
@@ -1500,9 +1496,11 @@ EXPORT_SYMBOL_GPL(dev_pm_genpd_resume);
 
 #endif /* CONFIG_PM_SLEEP */
 
-static struct generic_pm_domain_data *genpd_alloc_dev_data(struct device *dev)
+static struct generic_pm_domain_data *genpd_alloc_dev_data(struct device *dev,
+							   bool has_governor)
 {
 	struct generic_pm_domain_data *gpd_data;
+	struct gpd_timing_data *td;
 	int ret;
 
 	ret = dev_pm_get_subsys_data(dev);
@@ -1516,26 +1514,38 @@ static struct generic_pm_domain_data *genpd_alloc_dev_data(struct device *dev)
 	}
 
 	gpd_data->base.dev = dev;
-	gpd_data->td.constraint_changed = true;
-	gpd_data->td.effective_constraint_ns = PM_QOS_RESUME_LATENCY_NO_CONSTRAINT_NS;
 	gpd_data->nb.notifier_call = genpd_dev_pm_qos_notifier;
-	gpd_data->next_wakeup = KTIME_MAX;
 
-	spin_lock_irq(&dev->power.lock);
+	/* Allocate data used by a governor. */
+	if (has_governor) {
+		td = kzalloc(sizeof(*td), GFP_KERNEL);
+		if (!td) {
+			ret = -ENOMEM;
+			goto err_free;
+		}
 
-	if (dev->power.subsys_data->domain_data) {
-		ret = -EINVAL;
-		goto err_free;
+		td->constraint_changed = true;
+		td->effective_constraint_ns = PM_QOS_RESUME_LATENCY_NO_CONSTRAINT_NS;
+		td->next_wakeup = KTIME_MAX;
+		gpd_data->td = td;
 	}
 
-	dev->power.subsys_data->domain_data = &gpd_data->base;
+	spin_lock_irq(&dev->power.lock);
+
+	if (dev->power.subsys_data->domain_data)
+		ret = -EINVAL;
+	else
+		dev->power.subsys_data->domain_data = &gpd_data->base;
 
 	spin_unlock_irq(&dev->power.lock);
 
+	if (ret)
+		goto err_free;
+
 	return gpd_data;
 
  err_free:
-	spin_unlock_irq(&dev->power.lock);
+	kfree(gpd_data->td);
 	kfree(gpd_data);
  err_put:
 	dev_pm_put_subsys_data(dev);
@@ -1551,6 +1561,7 @@ static void genpd_free_dev_data(struct device *dev,
 
 	spin_unlock_irq(&dev->power.lock);
 
+	kfree(gpd_data->td);
 	kfree(gpd_data);
 	dev_pm_put_subsys_data(dev);
 }
@@ -1607,6 +1618,7 @@ static int genpd_get_cpu(struct generic_pm_domain *genpd, struct device *dev)
 static int genpd_add_device(struct generic_pm_domain *genpd, struct device *dev,
 			    struct device *base_dev)
 {
+	struct genpd_governor_data *gd = genpd->gd;
 	struct generic_pm_domain_data *gpd_data;
 	int ret;
 
@@ -1615,7 +1627,7 @@ static int genpd_add_device(struct generic_pm_domain *genpd, struct device *dev,
 	if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(dev))
 		return -EINVAL;
 
-	gpd_data = genpd_alloc_dev_data(dev);
+	gpd_data = genpd_alloc_dev_data(dev, gd);
 	if (IS_ERR(gpd_data))
 		return PTR_ERR(gpd_data);
 
@@ -1631,7 +1643,8 @@ static int genpd_add_device(struct generic_pm_domain *genpd, struct device *dev,
 	dev_pm_domain_set(dev, &genpd->domain);
 
 	genpd->device_count++;
-	genpd->max_off_time_changed = true;
+	if (gd)
+		gd->max_off_time_changed = true;
 
 	list_add_tail(&gpd_data->base.list_node, &genpd->dev_list);
 
@@ -1685,7 +1698,8 @@ static int genpd_remove_device(struct generic_pm_domain *genpd,
 	}
 
 	genpd->device_count--;
-	genpd->max_off_time_changed = true;
+	if (genpd->gd)
+		genpd->gd->max_off_time_changed = true;
 
 	genpd_clear_cpumask(genpd, gpd_data->cpu);
 	dev_pm_domain_set(dev, NULL);
@@ -1958,6 +1972,53 @@ static int genpd_set_default_power_state(struct generic_pm_domain *genpd)
 	return 0;
 }
 
+static int genpd_alloc_data(struct generic_pm_domain *genpd)
+{
+	struct genpd_governor_data *gd = NULL;
+	int ret;
+
+	if (genpd_is_cpu_domain(genpd) &&
+	    !zalloc_cpumask_var(&genpd->cpus, GFP_KERNEL))
+		return -ENOMEM;
+
+	if (genpd->gov) {
+		gd = kzalloc(sizeof(*gd), GFP_KERNEL);
+		if (!gd) {
+			ret = -ENOMEM;
+			goto free;
+		}
+
+		gd->max_off_time_ns = -1;
+		gd->max_off_time_changed = true;
+		gd->next_wakeup = KTIME_MAX;
+	}
+
+	/* Use only one "off" state if there were no states declared */
+	if (genpd->state_count == 0) {
+		ret = genpd_set_default_power_state(genpd);
+		if (ret)
+			goto free;
+	}
+
+	genpd->gd = gd;
+	return 0;
+
+free:
+	if (genpd_is_cpu_domain(genpd))
+		free_cpumask_var(genpd->cpus);
+	kfree(gd);
+	return ret;
+}
+
+static void genpd_free_data(struct generic_pm_domain *genpd)
+{
+	if (genpd_is_cpu_domain(genpd))
+		free_cpumask_var(genpd->cpus);
+	if (genpd->free_states)
+		genpd->free_states(genpd->states, genpd->state_count);
+	kfree(genpd->gd);
+}
+
 static void genpd_lock_init(struct generic_pm_domain *genpd)
 {
 	if (genpd->flags & GENPD_FLAG_IRQ_SAFE) {
@@ -1995,11 +2056,9 @@ int pm_genpd_init(struct generic_pm_domain *genpd,
 	atomic_set(&genpd->sd_count, 0);
 	genpd->status = is_off ? GENPD_STATE_OFF : GENPD_STATE_ON;
 	genpd->device_count = 0;
-	genpd->max_off_time_ns = -1;
-	genpd->max_off_time_changed = true;
 	genpd->provider = NULL;
 	genpd->has_provider = false;
-	genpd->accounting_time = ktime_get();
+	genpd->accounting_time = ktime_get_mono_fast_ns();
 	genpd->domain.ops.runtime_suspend = genpd_runtime_suspend;
 	genpd->domain.ops.runtime_resume = genpd_runtime_resume;
 	genpd->domain.ops.prepare = genpd_prepare;
@@ -2017,26 +2076,22 @@ int pm_genpd_init(struct generic_pm_domain *genpd,
 		genpd->dev_ops.start = pm_clk_resume;
 	}
 
+	/* The always-on governor works better with the corresponding flag. */
+	if (gov == &pm_domain_always_on_gov)
+		genpd->flags |= GENPD_FLAG_RPM_ALWAYS_ON;
+
 	/* Always-on domains must be powered on at initialization. */
 	if ((genpd_is_always_on(genpd) || genpd_is_rpm_always_on(genpd)) &&
 			!genpd_status_on(genpd))
 		return -EINVAL;
 
-	if (genpd_is_cpu_domain(genpd) &&
-	    !zalloc_cpumask_var(&genpd->cpus, GFP_KERNEL))
-		return -ENOMEM;
-
-	/* Use only one "off" state if there were no states declared */
-	if (genpd->state_count == 0) {
-		ret = genpd_set_default_power_state(genpd);
-		if (ret) {
-			if (genpd_is_cpu_domain(genpd))
-				free_cpumask_var(genpd->cpus);
-			return ret;
-		}
-	} else if (!gov && genpd->state_count > 1) {
+	/* Multiple states but no governor doesn't make sense. */
+	if (!gov && genpd->state_count > 1)
 		pr_warn("%s: no governor for states\n", genpd->name);
-	}
+
+	ret = genpd_alloc_data(genpd);
+	if (ret)
+		return ret;
 
 	device_initialize(&genpd->dev);
 	dev_set_name(&genpd->dev, "%s", genpd->name);
@@ -2081,10 +2136,7 @@ static int genpd_remove(struct generic_pm_domain *genpd)
 	genpd_unlock(genpd);
 	genpd_debug_remove(genpd);
 	cancel_work_sync(&genpd->power_off_work);
-	if (genpd_is_cpu_domain(genpd))
-		free_cpumask_var(genpd->cpus);
-	if (genpd->free_states)
-		genpd->free_states(genpd->states, genpd->state_count);
+	genpd_free_data(genpd);
 
 	pr_debug("%s: removed %s\n", __func__, genpd->name);
 
@@ -3163,6 +3215,7 @@ static int sub_domains_show(struct seq_file *s, void *data)
 static int idle_states_show(struct seq_file *s, void *data)
 {
 	struct generic_pm_domain *genpd = s->private;
+	u64 now, delta, idle_time = 0;
 	unsigned int i;
 	int ret = 0;
 
@@ -3173,17 +3226,19 @@ static int idle_states_show(struct seq_file *s, void *data)
 	seq_puts(s, "State          Time Spent(ms) Usage          Rejected\n");
 
 	for (i = 0; i < genpd->state_count; i++) {
-		ktime_t delta = 0;
-		s64 msecs;
+		idle_time += genpd->states[i].idle_time;
 
-		if ((genpd->status == GENPD_STATE_OFF) &&
-				(genpd->state_idx == i))
-			delta = ktime_sub(ktime_get(), genpd->accounting_time);
+		if (genpd->status == GENPD_STATE_OFF && genpd->state_idx == i) {
+			now = ktime_get_mono_fast_ns();
+			if (now > genpd->accounting_time) {
+				delta = now - genpd->accounting_time;
+				idle_time += delta;
+			}
+		}
 
-		msecs = ktime_to_ms(
-			ktime_add(genpd->states[i].idle_time, delta));
-		seq_printf(s, "S%-13i %-14lld %-14llu %llu\n", i, msecs,
-			      genpd->states[i].usage, genpd->states[i].rejected);
+		do_div(idle_time, NSEC_PER_MSEC);
+		seq_printf(s, "S%-13i %-14llu %-14llu %llu\n", i, idle_time,
+			   genpd->states[i].usage, genpd->states[i].rejected);
 	}
 
 	genpd_unlock(genpd);
@@ -3193,18 +3248,22 @@ static int idle_states_show(struct seq_file *s, void *data)
 static int active_time_show(struct seq_file *s, void *data)
 {
 	struct generic_pm_domain *genpd = s->private;
-	ktime_t delta = 0;
+	u64 now, on_time, delta = 0;
 	int ret = 0;
 
 	ret = genpd_lock_interruptible(genpd);
 	if (ret)
 		return -ERESTARTSYS;
 
-	if (genpd->status == GENPD_STATE_ON)
-		delta = ktime_sub(ktime_get(), genpd->accounting_time);
+	if (genpd->status == GENPD_STATE_ON) {
+		now = ktime_get_mono_fast_ns();
+		if (now > genpd->accounting_time)
+			delta = now - genpd->accounting_time;
+	}
 
-	seq_printf(s, "%lld ms\n", ktime_to_ms(
-				ktime_add(genpd->on_time, delta)));
+	on_time = genpd->on_time + delta;
+	do_div(on_time, NSEC_PER_MSEC);
+	seq_printf(s, "%llu ms\n", on_time);
 
 	genpd_unlock(genpd);
 	return ret;
@@ -3213,7 +3272,7 @@ static int active_time_show(struct seq_file *s, void *data)
 static int total_idle_time_show(struct seq_file *s, void *data)
 {
 	struct generic_pm_domain *genpd = s->private;
-	ktime_t delta = 0, total = 0;
+	u64 now, delta, total = 0;
 	unsigned int i;
 	int ret = 0;
 
@@ -3222,16 +3281,19 @@ static int total_idle_time_show(struct seq_file *s, void *data)
 		return -ERESTARTSYS;
 
 	for (i = 0; i < genpd->state_count; i++) {
+		total += genpd->states[i].idle_time;
 
-		if ((genpd->status == GENPD_STATE_OFF) &&
-				(genpd->state_idx == i))
-			delta = ktime_sub(ktime_get(), genpd->accounting_time);
-
-		total = ktime_add(total, genpd->states[i].idle_time);
+		if (genpd->status == GENPD_STATE_OFF && genpd->state_idx == i) {
+			now = ktime_get_mono_fast_ns();
+			if (now > genpd->accounting_time) {
+				delta = now - genpd->accounting_time;
+				total += delta;
+			}
+		}
 	}
-	total = ktime_add(total, delta);
 
-	seq_printf(s, "%lld ms\n", ktime_to_ms(total));
+	do_div(total, NSEC_PER_MSEC);
+	seq_printf(s, "%llu ms\n", total);
 
 	genpd_unlock(genpd);
 	return ret;
diff --git a/drivers/base/power/domain_governor.c b/drivers/base/power/domain_governor.c
index cd08c5885190..282a3a135827 100644
--- a/drivers/base/power/domain_governor.c
+++ b/drivers/base/power/domain_governor.c
@@ -18,6 +18,8 @@ static int dev_update_qos_constraint(struct device *dev, void *data)
 	s64 constraint_ns;
 
 	if (dev->power.subsys_data && dev->power.subsys_data->domain_data) {
+		struct gpd_timing_data *td = dev_gpd_data(dev)->td;
+
 		/*
 		 * Only take suspend-time QoS constraints of devices into
 		 * account, because constraints updated after the device has
@@ -25,7 +27,8 @@ static int dev_update_qos_constraint(struct device *dev, void *data)
 		 * anyway.  In order for them to take effect, the device has to
 		 * be resumed and suspended again.
 		 */
-		constraint_ns = dev_gpd_data(dev)->td.effective_constraint_ns;
+		constraint_ns = td ? td->effective_constraint_ns :
+				PM_QOS_RESUME_LATENCY_NO_CONSTRAINT_NS;
 	} else {
 		/*
 		 * The child is not in a domain and there's no info on its
@@ -49,7 +52,7 @@ static int dev_update_qos_constraint(struct device *dev, void *data)
  */
 static bool default_suspend_ok(struct device *dev)
 {
-	struct gpd_timing_data *td = &dev_gpd_data(dev)->td;
+	struct gpd_timing_data *td = dev_gpd_data(dev)->td;
 	unsigned long flags;
 	s64 constraint_ns;
 
@@ -136,26 +139,28 @@ static void update_domain_next_wakeup(struct generic_pm_domain *genpd, ktime_t n
 	 * is able to enter its optimal idle state.
 	 */
 	list_for_each_entry(pdd, &genpd->dev_list, list_node) {
-		next_wakeup = to_gpd_data(pdd)->next_wakeup;
+		next_wakeup = to_gpd_data(pdd)->td->next_wakeup;
 		if (next_wakeup != KTIME_MAX && !ktime_before(next_wakeup, now))
 			if (ktime_before(next_wakeup, domain_wakeup))
 				domain_wakeup = next_wakeup;
 	}
 
 	list_for_each_entry(link, &genpd->parent_links, parent_node) {
-		next_wakeup = link->child->next_wakeup;
+		struct genpd_governor_data *cgd = link->child->gd;
+
+		next_wakeup = cgd ? cgd->next_wakeup : KTIME_MAX;
 		if (next_wakeup != KTIME_MAX && !ktime_before(next_wakeup, now))
 			if (ktime_before(next_wakeup, domain_wakeup))
 				domain_wakeup = next_wakeup;
 	}
 
-	genpd->next_wakeup = domain_wakeup;
+	genpd->gd->next_wakeup = domain_wakeup;
 }
 
 static bool next_wakeup_allows_state(struct generic_pm_domain *genpd,
 				     unsigned int state, ktime_t now)
 {
-	ktime_t domain_wakeup = genpd->next_wakeup;
+	ktime_t domain_wakeup = genpd->gd->next_wakeup;
 	s64 idle_time_ns, min_sleep_ns;
 
 	min_sleep_ns = genpd->states[state].power_off_latency_ns +
@@ -185,8 +190,9 @@ static bool __default_power_down_ok(struct dev_pm_domain *pd,
 	 * All subdomains have been powered off already at this point.
 	 */
 	list_for_each_entry(link, &genpd->parent_links, parent_node) {
-		struct generic_pm_domain *sd = link->child;
-		s64 sd_max_off_ns = sd->max_off_time_ns;
+		struct genpd_governor_data *cgd = link->child->gd;
+
+		s64 sd_max_off_ns = cgd ? cgd->max_off_time_ns : -1;
 
 		if (sd_max_off_ns < 0)
 			continue;
@@ -215,7 +221,7 @@ static bool __default_power_down_ok(struct dev_pm_domain *pd,
 		 * domain to turn off and on (that's how much time it will
 		 * have to wait worst case).
 		 */
-		td = &to_gpd_data(pdd)->td;
+		td = to_gpd_data(pdd)->td;
 		constraint_ns = td->effective_constraint_ns;
 		/*
 		 * Zero means "no suspend at all" and this runs only when all
@@ -244,7 +250,7 @@ static bool __default_power_down_ok(struct dev_pm_domain *pd,
 	 * time and the time needed to turn the domain on is the maximum
 	 * theoretical time this domain can spend in the "off" state.
 	 */
-	genpd->max_off_time_ns = min_off_time_ns -
+	genpd->gd->max_off_time_ns = min_off_time_ns -
 		genpd->states[state].power_on_latency_ns;
 	return true;
 }
@@ -259,6 +265,7 @@ static bool __default_power_down_ok(struct dev_pm_domain *pd,
 static bool _default_power_down_ok(struct dev_pm_domain *pd, ktime_t now)
 {
 	struct generic_pm_domain *genpd = pd_to_genpd(pd);
+	struct genpd_governor_data *gd = genpd->gd;
 	int state_idx = genpd->state_count - 1;
 	struct gpd_link *link;
 
@@ -269,11 +276,11 @@ static bool _default_power_down_ok(struct dev_pm_domain *pd, ktime_t now)
 	 * cannot be met.
 	 */
 	update_domain_next_wakeup(genpd, now);
-	if ((genpd->flags & GENPD_FLAG_MIN_RESIDENCY) && (genpd->next_wakeup != KTIME_MAX)) {
+	if ((genpd->flags & GENPD_FLAG_MIN_RESIDENCY) && (gd->next_wakeup != KTIME_MAX)) {
 		/* Let's find out the deepest domain idle state, the devices prefer */
 		while (state_idx >= 0) {
 			if (next_wakeup_allows_state(genpd, state_idx, now)) {
-				genpd->max_off_time_changed = true;
+				gd->max_off_time_changed = true;
 				break;
 			}
 			state_idx--;
@@ -281,14 +288,14 @@ static bool _default_power_down_ok(struct dev_pm_domain *pd, ktime_t now)
 
 		if (state_idx < 0) {
 			state_idx = 0;
-			genpd->cached_power_down_ok = false;
+			gd->cached_power_down_ok = false;
 			goto done;
 		}
 	}
 
-	if (!genpd->max_off_time_changed) {
-		genpd->state_idx = genpd->cached_power_down_state_idx;
-		return genpd->cached_power_down_ok;
+	if (!gd->max_off_time_changed) {
+		genpd->state_idx = gd->cached_power_down_state_idx;
+		return gd->cached_power_down_ok;
 	}
 
 	/*
@@ -297,12 +304,16 @@ static bool _default_power_down_ok(struct dev_pm_domain *pd, ktime_t now)
 	 * going to be called for any parent until this instance
 	 * returns.
 	 */
-	list_for_each_entry(link, &genpd->child_links, child_node)
-		link->parent->max_off_time_changed = true;
+	list_for_each_entry(link, &genpd->child_links, child_node) {
+		struct genpd_governor_data *pgd = link->parent->gd;
+
+		if (pgd)
+			pgd->max_off_time_changed = true;
+	}
 
-	genpd->max_off_time_ns = -1;
-	genpd->max_off_time_changed = false;
-	genpd->cached_power_down_ok = true;
+	gd->max_off_time_ns = -1;
+	gd->max_off_time_changed = false;
+	gd->cached_power_down_ok = true;
 
 	/*
 	 * Find a state to power down to, starting from the state
@@ -310,7 +321,7 @@ static bool _default_power_down_ok(struct dev_pm_domain *pd, ktime_t now)
 	 */
 	while (!__default_power_down_ok(pd, state_idx)) {
 		if (state_idx == 0) {
-			genpd->cached_power_down_ok = false;
+			gd->cached_power_down_ok = false;
 			break;
 		}
 		state_idx--;
@@ -318,8 +329,8 @@ static bool _default_power_down_ok(struct dev_pm_domain *pd, ktime_t now)
 
 done:
 	genpd->state_idx = state_idx;
-	genpd->cached_power_down_state_idx = genpd->state_idx;
-	return genpd->cached_power_down_ok;
+	gd->cached_power_down_state_idx = genpd->state_idx;
+	return gd->cached_power_down_ok;
 }
 
 static bool default_power_down_ok(struct dev_pm_domain *pd)
@@ -327,11 +338,6 @@ static bool default_power_down_ok(struct dev_pm_domain *pd)
 	return _default_power_down_ok(pd, ktime_get());
 }
 
-static bool always_on_power_down_ok(struct dev_pm_domain *domain)
-{
-	return false;
-}
-
 #ifdef CONFIG_CPU_IDLE
 static bool cpu_power_down_ok(struct dev_pm_domain *pd)
 {
@@ -401,6 +407,5 @@ struct dev_power_governor simple_qos_governor = {
  * pm_genpd_gov_always_on - A governor implementing an always-on policy
  */
 struct dev_power_governor pm_domain_always_on_gov = {
-	.power_down_ok = always_on_power_down_ok,
 	.suspend_ok = default_suspend_ok,
 };
diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c
index d4059e6ffeae..676dc72d912d 100644
--- a/drivers/base/power/runtime.c
+++ b/drivers/base/power/runtime.c
@@ -263,7 +263,7 @@ static int rpm_check_suspend_allowed(struct device *dev)
 		retval = -EINVAL;
 	else if (dev->power.disable_depth > 0)
 		retval = -EACCES;
-	else if (atomic_read(&dev->power.usage_count) > 0)
+	else if (atomic_read(&dev->power.usage_count))
 		retval = -EAGAIN;
 	else if (!dev->power.ignore_children &&
 			atomic_read(&dev->power.child_count))
@@ -1039,13 +1039,33 @@ int pm_schedule_suspend(struct device *dev, unsigned int delay)
 }
 EXPORT_SYMBOL_GPL(pm_schedule_suspend);
 
+static int rpm_drop_usage_count(struct device *dev)
+{
+	int ret;
+
+	ret = atomic_sub_return(1, &dev->power.usage_count);
+	if (ret >= 0)
+		return ret;
+
+	/*
+	 * Because rpm_resume() does not check the usage counter, it will resume
+	 * the device even if the usage counter is 0 or negative, so it is
+	 * sufficient to increment the usage counter here to reverse the change
+	 * made above.
+	 */
+	atomic_inc(&dev->power.usage_count);
+	dev_warn(dev, "Runtime PM usage count underflow!\n");
+	return -EINVAL;
+}
+
 /**
  * __pm_runtime_idle - Entry point for runtime idle operations.
  * @dev: Device to send idle notification for.
  * @rpmflags: Flag bits.
  *
  * If the RPM_GET_PUT flag is set, decrement the device's usage count and
- * return immediately if it is larger than zero.  Then carry out an idle
+ * return immediately if it is larger than zero (if it becomes negative, log a
+ * warning, increment it, and return an error).  Then carry out an idle
  * notification, either synchronous or asynchronous.
  *
  * This routine may be called in atomic context if the RPM_ASYNC flag is set,
@@ -1057,7 +1077,10 @@ int __pm_runtime_idle(struct device *dev, int rpmflags)
 	int retval;
 
 	if (rpmflags & RPM_GET_PUT) {
-		if (!atomic_dec_and_test(&dev->power.usage_count)) {
+		retval = rpm_drop_usage_count(dev);
+		if (retval < 0) {
+			return retval;
+		} else if (retval > 0) {
 			trace_rpm_usage_rcuidle(dev, rpmflags);
 			return 0;
 		}
@@ -1079,7 +1102,8 @@ EXPORT_SYMBOL_GPL(__pm_runtime_idle);
  * @rpmflags: Flag bits.
  *
  * If the RPM_GET_PUT flag is set, decrement the device's usage count and
- * return immediately if it is larger than zero.  Then carry out a suspend,
+ * return immediately if it is larger than zero (if it becomes negative, log a
+ * warning, increment it, and return an error).  Then carry out a suspend,
  * either synchronous or asynchronous.
  *
  * This routine may be called in atomic context if the RPM_ASYNC flag is set,
@@ -1091,7 +1115,10 @@ int __pm_runtime_suspend(struct device *dev, int rpmflags)
 	int retval;
 
 	if (rpmflags & RPM_GET_PUT) {
-		if (!atomic_dec_and_test(&dev->power.usage_count)) {
+		retval = rpm_drop_usage_count(dev);
+		if (retval < 0) {
+			return retval;
+		} else if (retval > 0) {
 			trace_rpm_usage_rcuidle(dev, rpmflags);
 			return 0;
 		}
@@ -1210,12 +1237,13 @@ int __pm_runtime_set_status(struct device *dev, unsigned int status)
 {
 	struct device *parent = dev->parent;
 	bool notify_parent = false;
+	unsigned long flags;
 	int error = 0;
 
 	if (status != RPM_ACTIVE && status != RPM_SUSPENDED)
 		return -EINVAL;
 
-	spin_lock_irq(&dev->power.lock);
+	spin_lock_irqsave(&dev->power.lock, flags);
 
 	/*
 	 * Prevent PM-runtime from being enabled for the device or return an
@@ -1226,7 +1254,7 @@ int __pm_runtime_set_status(struct device *dev, unsigned int status)
 	else
 		error = -EAGAIN;
 
-	spin_unlock_irq(&dev->power.lock);
+	spin_unlock_irqrestore(&dev->power.lock, flags);
 
 	if (error)
 		return error;
@@ -1247,7 +1275,7 @@ int __pm_runtime_set_status(struct device *dev, unsigned int status)
 		device_links_read_unlock(idx);
 	}
 
-	spin_lock_irq(&dev->power.lock);
+	spin_lock_irqsave(&dev->power.lock, flags);
 
 	if (dev->power.runtime_status == status || !parent)
 		goto out_set;
@@ -1288,7 +1316,7 @@ int __pm_runtime_set_status(struct device *dev, unsigned int status)
 		dev->power.runtime_error = 0;
 
  out:
-	spin_unlock_irq(&dev->power.lock);
+	spin_unlock_irqrestore(&dev->power.lock, flags);
 
 	if (notify_parent)
 		pm_request_idle(parent);
@@ -1527,14 +1555,17 @@ EXPORT_SYMBOL_GPL(pm_runtime_forbid);
  */
 void pm_runtime_allow(struct device *dev)
 {
+	int ret;
+
 	spin_lock_irq(&dev->power.lock);
 	if (dev->power.runtime_auto)
 		goto out;
 
 	dev->power.runtime_auto = true;
-	if (atomic_dec_and_test(&dev->power.usage_count))
+	ret = rpm_drop_usage_count(dev);
+	if (ret == 0)
 		rpm_idle(dev, RPM_AUTO | RPM_ASYNC);
-	else
+	else if (ret > 0)
 		trace_rpm_usage_rcuidle(dev, RPM_AUTO | RPM_ASYNC);
 
  out: