diff --git a/drivers/base/cpu.c b/drivers/base/cpu.c
index eb9443d5bae1..6ce93a52bf3f 100644
--- a/drivers/base/cpu.c
+++ b/drivers/base/cpu.c
@@ -427,6 +427,7 @@ __cpu_device_create(struct device *parent, void *drvdata,
 	dev->parent = parent;
 	dev->groups = groups;
 	dev->release = device_create_release;
+	device_set_pm_not_required(dev);
 	dev_set_drvdata(dev, drvdata);
 
 	retval = kobject_set_name_vargs(&dev->kobj, fmt, args);
diff --git a/drivers/base/power/clock_ops.c b/drivers/base/power/clock_ops.c
index 5a42ae4078c2..365ad751ce0f 100644
--- a/drivers/base/power/clock_ops.c
+++ b/drivers/base/power/clock_ops.c
@@ -65,10 +65,15 @@ static void pm_clk_acquire(struct device *dev, struct pm_clock_entry *ce)
 	if (IS_ERR(ce->clk)) {
 		ce->status = PCE_STATUS_ERROR;
 	} else {
-		clk_prepare(ce->clk);
-		ce->status = PCE_STATUS_ACQUIRED;
-		dev_dbg(dev, "Clock %pC con_id %s managed by runtime PM.\n",
-			ce->clk, ce->con_id);
+		if (clk_prepare(ce->clk)) {
+			ce->status = PCE_STATUS_ERROR;
+			dev_err(dev, "clk_prepare() failed\n");
+		} else {
+			ce->status = PCE_STATUS_ACQUIRED;
+			dev_dbg(dev,
+				"Clock %pC con_id %s managed by runtime PM.\n",
+				ce->clk, ce->con_id);
+		}
 	}
 }
 
diff --git a/drivers/base/power/common.c b/drivers/base/power/common.c
index b413951c6abc..22aedb28aad7 100644
--- a/drivers/base/power/common.c
+++ b/drivers/base/power/common.c
@@ -160,7 +160,7 @@ EXPORT_SYMBOL_GPL(dev_pm_domain_attach_by_id);
  * For a detailed function description, see dev_pm_domain_attach_by_id().
  */
 struct device *dev_pm_domain_attach_by_name(struct device *dev,
-					    char *name)
+					    const char *name)
 {
 	if (dev->pm_domain)
 		return ERR_PTR(-EEXIST);
diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
index 500de1dee967..2c334c01fc43 100644
--- a/drivers/base/power/domain.c
+++ b/drivers/base/power/domain.c
@@ -2483,7 +2483,7 @@ EXPORT_SYMBOL_GPL(genpd_dev_pm_attach_by_id);
  * power-domain-names DT property. For further description see
  * genpd_dev_pm_attach_by_id().
  */
-struct device *genpd_dev_pm_attach_by_name(struct device *dev, char *name)
+struct device *genpd_dev_pm_attach_by_name(struct device *dev, const char *name)
 {
 	int index;
 
@@ -2948,18 +2948,11 @@ static int __init genpd_debug_init(void)
 
 	genpd_debugfs_dir = debugfs_create_dir("pm_genpd", NULL);
 
-	if (!genpd_debugfs_dir)
-		return -ENOMEM;
-
-	d = debugfs_create_file("pm_genpd_summary", S_IRUGO,
-			genpd_debugfs_dir, NULL, &summary_fops);
-	if (!d)
-		return -ENOMEM;
+	debugfs_create_file("pm_genpd_summary", S_IRUGO, genpd_debugfs_dir,
+			    NULL, &summary_fops);
 
 	list_for_each_entry(genpd, &gpd_list, gpd_list_node) {
 		d = debugfs_create_dir(genpd->name, genpd_debugfs_dir);
-		if (!d)
-			return -ENOMEM;
 
 		debugfs_create_file("current_state", 0444,
 				d, genpd, &status_fops);
diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c
index 0992e67e862b..893ae464bfd6 100644
--- a/drivers/base/power/main.c
+++ b/drivers/base/power/main.c
@@ -124,6 +124,10 @@ void device_pm_unlock(void)
  */
 void device_pm_add(struct device *dev)
 {
+	/* Skip PM setup/initialization. */
+	if (device_pm_not_required(dev))
+		return;
+
 	pr_debug("PM: Adding info for %s:%s\n",
 		 dev->bus ? dev->bus->name : "No Bus", dev_name(dev));
 	device_pm_check_callbacks(dev);
@@ -142,6 +146,9 @@ void device_pm_add(struct device *dev)
  */
 void device_pm_remove(struct device *dev)
 {
+	if (device_pm_not_required(dev))
+		return;
+
 	pr_debug("PM: Removing info for %s:%s\n",
 		 dev->bus ? dev->bus->name : "No Bus", dev_name(dev));
 	complete_all(&dev->power.completion);
@@ -1741,8 +1748,10 @@ static int __device_suspend(struct device *dev, pm_message_t state, bool async)
 	if (dev->power.direct_complete) {
 		if (pm_runtime_status_suspended(dev)) {
 			pm_runtime_disable(dev);
-			if (pm_runtime_status_suspended(dev))
+			if (pm_runtime_status_suspended(dev)) {
+				pm_dev_dbg(dev, state, "direct-complete ");
 				goto Complete;
+			}
 
 			pm_runtime_enable(dev);
 		}
diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c
index ccd296dbb95c..78937c45278c 100644
--- a/drivers/base/power/runtime.c
+++ b/drivers/base/power/runtime.c
@@ -66,20 +66,30 @@ static int rpm_suspend(struct device *dev, int rpmflags);
  */
 void update_pm_runtime_accounting(struct device *dev)
 {
-	unsigned long now = jiffies;
-	unsigned long delta;
-
-	delta = now - dev->power.accounting_timestamp;
-
-	dev->power.accounting_timestamp = now;
+	u64 now, last, delta;
 
 	if (dev->power.disable_depth > 0)
 		return;
 
+	last = dev->power.accounting_timestamp;
+
+	now = ktime_get_mono_fast_ns();
+	dev->power.accounting_timestamp = now;
+
+	/*
+	 * Because ktime_get_mono_fast_ns() is not monotonic during
+	 * timekeeping updates, ensure that 'now' is after the last saved
+	 * timesptamp.
+	 */
+	if (now < last)
+		return;
+
+	delta = now - last;
+
 	if (dev->power.runtime_status == RPM_SUSPENDED)
-		dev->power.suspended_jiffies += delta;
+		dev->power.suspended_time += delta;
 	else
-		dev->power.active_jiffies += delta;
+		dev->power.active_time += delta;
 }
 
 static void __update_runtime_status(struct device *dev, enum rpm_status status)
@@ -88,6 +98,22 @@ static void __update_runtime_status(struct device *dev, enum rpm_status status)
 	dev->power.runtime_status = status;
 }
 
+u64 pm_runtime_suspended_time(struct device *dev)
+{
+	u64 time;
+	unsigned long flags;
+
+	spin_lock_irqsave(&dev->power.lock, flags);
+
+	update_pm_runtime_accounting(dev);
+	time = dev->power.suspended_time;
+
+	spin_unlock_irqrestore(&dev->power.lock, flags);
+
+	return time;
+}
+EXPORT_SYMBOL_GPL(pm_runtime_suspended_time);
+
 /**
  * pm_runtime_deactivate_timer - Deactivate given device's suspend timer.
  * @dev: Device to handle.
@@ -129,24 +155,21 @@ static void pm_runtime_cancel_pending(struct device *dev)
 u64 pm_runtime_autosuspend_expiration(struct device *dev)
 {
 	int autosuspend_delay;
-	u64 last_busy, expires = 0;
-	u64 now = ktime_get_mono_fast_ns();
+	u64 expires;
 
 	if (!dev->power.use_autosuspend)
-		goto out;
+		return 0;
 
 	autosuspend_delay = READ_ONCE(dev->power.autosuspend_delay);
 	if (autosuspend_delay < 0)
-		goto out;
+		return 0;
 
-	last_busy = READ_ONCE(dev->power.last_busy);
+	expires  = READ_ONCE(dev->power.last_busy);
+	expires += (u64)autosuspend_delay * NSEC_PER_MSEC;
+	if (expires > ktime_get_mono_fast_ns())
+		return expires;	/* Expires in the future */
 
-	expires = last_busy + (u64)autosuspend_delay * NSEC_PER_MSEC;
-	if (expires <= now)
-		expires = 0;	/* Already expired. */
-
- out:
-	return expires;
+	return 0;
 }
 EXPORT_SYMBOL_GPL(pm_runtime_autosuspend_expiration);
 
@@ -1276,6 +1299,9 @@ void __pm_runtime_disable(struct device *dev, bool check_resume)
 		pm_runtime_put_noidle(dev);
 	}
 
+	/* Update time accounting before disabling PM-runtime. */
+	update_pm_runtime_accounting(dev);
+
 	if (!dev->power.disable_depth++)
 		__pm_runtime_barrier(dev);
 
@@ -1294,10 +1320,15 @@ void pm_runtime_enable(struct device *dev)
 
 	spin_lock_irqsave(&dev->power.lock, flags);
 
-	if (dev->power.disable_depth > 0)
+	if (dev->power.disable_depth > 0) {
 		dev->power.disable_depth--;
-	else
+
+		/* About to enable runtime pm, set accounting_timestamp to now */
+		if (!dev->power.disable_depth)
+			dev->power.accounting_timestamp = ktime_get_mono_fast_ns();
+	} else {
 		dev_warn(dev, "Unbalanced %s!\n", __func__);
+	}
 
 	WARN(!dev->power.disable_depth &&
 	     dev->power.runtime_status == RPM_SUSPENDED &&
@@ -1494,7 +1525,6 @@ void pm_runtime_init(struct device *dev)
 	dev->power.request_pending = false;
 	dev->power.request = RPM_REQ_NONE;
 	dev->power.deferred_resume = false;
-	dev->power.accounting_timestamp = jiffies;
 	INIT_WORK(&dev->power.work, pm_runtime_work);
 
 	dev->power.timer_expires = 0;
diff --git a/drivers/base/power/sysfs.c b/drivers/base/power/sysfs.c
index d713738ce796..c6bf76124184 100644
--- a/drivers/base/power/sysfs.c
+++ b/drivers/base/power/sysfs.c
@@ -125,9 +125,12 @@ static ssize_t runtime_active_time_show(struct device *dev,
 				struct device_attribute *attr, char *buf)
 {
 	int ret;
+	u64 tmp;
 	spin_lock_irq(&dev->power.lock);
 	update_pm_runtime_accounting(dev);
-	ret = sprintf(buf, "%i\n", jiffies_to_msecs(dev->power.active_jiffies));
+	tmp = dev->power.active_time;
+	do_div(tmp, NSEC_PER_MSEC);
+	ret = sprintf(buf, "%llu\n", tmp);
 	spin_unlock_irq(&dev->power.lock);
 	return ret;
 }
@@ -138,10 +141,12 @@ static ssize_t runtime_suspended_time_show(struct device *dev,
 				struct device_attribute *attr, char *buf)
 {
 	int ret;
+	u64 tmp;
 	spin_lock_irq(&dev->power.lock);
 	update_pm_runtime_accounting(dev);
-	ret = sprintf(buf, "%i\n",
-		jiffies_to_msecs(dev->power.suspended_jiffies));
+	tmp = dev->power.suspended_time;
+	do_div(tmp, NSEC_PER_MSEC);
+	ret = sprintf(buf, "%llu\n", tmp);
 	spin_unlock_irq(&dev->power.lock);
 	return ret;
 }
@@ -648,6 +653,10 @@ int dpm_sysfs_add(struct device *dev)
 {
 	int rc;
 
+	/* No need to create PM sysfs if explicitly disabled. */
+	if (device_pm_not_required(dev))
+		return 0;
+
 	rc = sysfs_create_group(&dev->kobj, &pm_attr_group);
 	if (rc)
 		return rc;
@@ -727,6 +736,8 @@ void rpm_sysfs_remove(struct device *dev)
 
 void dpm_sysfs_remove(struct device *dev)
 {
+	if (device_pm_not_required(dev))
+		return;
 	sysfs_unmerge_group(&dev->kobj, &pm_qos_latency_tolerance_attr_group);
 	dev_pm_qos_constraints_destroy(dev);
 	rpm_sysfs_remove(dev);
diff --git a/drivers/base/power/wakeup.c b/drivers/base/power/wakeup.c
index 5fa1898755a3..f1fee72ed970 100644
--- a/drivers/base/power/wakeup.c
+++ b/drivers/base/power/wakeup.c
@@ -783,7 +783,7 @@ void pm_wakeup_ws_event(struct wakeup_source *ws, unsigned int msec, bool hard)
 EXPORT_SYMBOL_GPL(pm_wakeup_ws_event);
 
 /**
- * pm_wakeup_event - Notify the PM core of a wakeup event.
+ * pm_wakeup_dev_event - Notify the PM core of a wakeup event.
  * @dev: Device the wakeup event is related to.
  * @msec: Anticipated event processing time (in milliseconds).
  * @hard: If set, abort suspends in progress and wake up from suspend-to-idle.
diff --git a/drivers/gpu/drm/i915/i915_pmu.c b/drivers/gpu/drm/i915/i915_pmu.c
index 017fc602a10e..cf7c66bb3ed9 100644
--- a/drivers/gpu/drm/i915/i915_pmu.c
+++ b/drivers/gpu/drm/i915/i915_pmu.c
@@ -5,6 +5,7 @@
  */
 
 #include <linux/irq.h>
+#include <linux/pm_runtime.h>
 #include "i915_pmu.h"
 #include "intel_ringbuffer.h"
 #include "i915_drv.h"
@@ -478,7 +479,6 @@ static u64 get_rc6(struct drm_i915_private *i915)
 		 * counter value.
 		 */
 		spin_lock_irqsave(&i915->pmu.lock, flags);
-		spin_lock(&kdev->power.lock);
 
 		/*
 		 * After the above branch intel_runtime_pm_get_if_in_use failed
@@ -491,16 +491,13 @@ static u64 get_rc6(struct drm_i915_private *i915)
 		 * suspended and if not we cannot do better than report the last
 		 * known RC6 value.
 		 */
-		if (kdev->power.runtime_status == RPM_SUSPENDED) {
+		if (pm_runtime_status_suspended(kdev)) {
+			val = pm_runtime_suspended_time(kdev);
+
 			if (!i915->pmu.sample[__I915_SAMPLE_RC6_ESTIMATED].cur)
-				i915->pmu.suspended_jiffies_last =
-						  kdev->power.suspended_jiffies;
+				i915->pmu.suspended_time_last = val;
 
-			val = kdev->power.suspended_jiffies -
-			      i915->pmu.suspended_jiffies_last;
-			val += jiffies - kdev->power.accounting_timestamp;
-
-			val = jiffies_to_nsecs(val);
+			val -= i915->pmu.suspended_time_last;
 			val += i915->pmu.sample[__I915_SAMPLE_RC6].cur;
 
 			i915->pmu.sample[__I915_SAMPLE_RC6_ESTIMATED].cur = val;
@@ -510,7 +507,6 @@ static u64 get_rc6(struct drm_i915_private *i915)
 			val = i915->pmu.sample[__I915_SAMPLE_RC6].cur;
 		}
 
-		spin_unlock(&kdev->power.lock);
 		spin_unlock_irqrestore(&i915->pmu.lock, flags);
 	}
 
diff --git a/drivers/gpu/drm/i915/i915_pmu.h b/drivers/gpu/drm/i915/i915_pmu.h
index b3728c5f13e7..4fc4f2478301 100644
--- a/drivers/gpu/drm/i915/i915_pmu.h
+++ b/drivers/gpu/drm/i915/i915_pmu.h
@@ -97,9 +97,9 @@ struct i915_pmu {
 	 */
 	struct i915_pmu_sample sample[__I915_NUM_PMU_SAMPLERS];
 	/**
-	 * @suspended_jiffies_last: Cached suspend time from PM core.
+	 * @suspended_time_last: Cached suspend time from PM core.
 	 */
-	unsigned long suspended_jiffies_last;
+	u64 suspended_time_last;
 	/**
 	 * @i915_attr: Memory block holding device attributes.
 	 */
diff --git a/include/linux/device.h b/include/linux/device.h
index 6cb4640b6160..53028636fe39 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -1165,6 +1165,16 @@ static inline bool device_async_suspend_enabled(struct device *dev)
 	return !!dev->power.async_suspend;
 }
 
+static inline bool device_pm_not_required(struct device *dev)
+{
+	return dev->power.no_pm;
+}
+
+static inline void device_set_pm_not_required(struct device *dev)
+{
+	dev->power.no_pm = true;
+}
+
 static inline void dev_pm_syscore_device(struct device *dev, bool val)
 {
 #ifdef CONFIG_PM_SLEEP
diff --git a/include/linux/pm.h b/include/linux/pm.h
index 0bd9de116826..06f7ed893928 100644
--- a/include/linux/pm.h
+++ b/include/linux/pm.h
@@ -592,6 +592,7 @@ struct dev_pm_info {
 	bool			is_suspended:1;	/* Ditto */
 	bool			is_noirq_suspended:1;
 	bool			is_late_suspended:1;
+	bool			no_pm:1;
 	bool			early_init:1;	/* Owned by the PM core */
 	bool			direct_complete:1;	/* Owned by the PM core */
 	u32			driver_flags;
@@ -633,9 +634,9 @@ struct dev_pm_info {
 	int			runtime_error;
 	int			autosuspend_delay;
 	u64			last_busy;
-	unsigned long		active_jiffies;
-	unsigned long		suspended_jiffies;
-	unsigned long		accounting_timestamp;
+	u64			active_time;
+	u64			suspended_time;
+	u64			accounting_timestamp;
 #endif
 	struct pm_subsys_data	*subsys_data;  /* Owned by the subsystem. */
 	void (*set_latency_tolerance)(struct device *, s32);
diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h
index dd364abb649a..1ed5874bcee0 100644
--- a/include/linux/pm_domain.h
+++ b/include/linux/pm_domain.h
@@ -271,7 +271,7 @@ int genpd_dev_pm_attach(struct device *dev);
 struct device *genpd_dev_pm_attach_by_id(struct device *dev,
 					 unsigned int index);
 struct device *genpd_dev_pm_attach_by_name(struct device *dev,
-					   char *name);
+					   const char *name);
 #else /* !CONFIG_PM_GENERIC_DOMAINS_OF */
 static inline int of_genpd_add_provider_simple(struct device_node *np,
 					struct generic_pm_domain *genpd)
@@ -324,7 +324,7 @@ static inline struct device *genpd_dev_pm_attach_by_id(struct device *dev,
 }
 
 static inline struct device *genpd_dev_pm_attach_by_name(struct device *dev,
-							 char *name)
+							 const char *name)
 {
 	return NULL;
 }
@@ -341,7 +341,7 @@ int dev_pm_domain_attach(struct device *dev, bool power_on);
 struct device *dev_pm_domain_attach_by_id(struct device *dev,
 					  unsigned int index);
 struct device *dev_pm_domain_attach_by_name(struct device *dev,
-					    char *name);
+					    const char *name);
 void dev_pm_domain_detach(struct device *dev, bool power_off);
 void dev_pm_domain_set(struct device *dev, struct dev_pm_domain *pd);
 #else
@@ -355,7 +355,7 @@ static inline struct device *dev_pm_domain_attach_by_id(struct device *dev,
 	return NULL;
 }
 static inline struct device *dev_pm_domain_attach_by_name(struct device *dev,
-							  char *name)
+							  const char *name)
 {
 	return NULL;
 }
diff --git a/include/linux/pm_runtime.h b/include/linux/pm_runtime.h
index fed5be706bc9..9dc6eebf62d2 100644
--- a/include/linux/pm_runtime.h
+++ b/include/linux/pm_runtime.h
@@ -113,6 +113,8 @@ static inline bool pm_runtime_is_irq_safe(struct device *dev)
 	return dev->power.irq_safe;
 }
 
+extern u64 pm_runtime_suspended_time(struct device *dev);
+
 #else /* !CONFIG_PM */
 
 static inline bool queue_pm_work(struct work_struct *work) { return false; }
diff --git a/kernel/power/energy_model.c b/kernel/power/energy_model.c
index d9dc2c38764a..7d66ee68aaaf 100644
--- a/kernel/power/energy_model.c
+++ b/kernel/power/energy_model.c
@@ -10,6 +10,7 @@
 
 #include <linux/cpu.h>
 #include <linux/cpumask.h>
+#include <linux/debugfs.h>
 #include <linux/energy_model.h>
 #include <linux/sched/topology.h>
 #include <linux/slab.h>
@@ -23,6 +24,60 @@ static DEFINE_PER_CPU(struct em_perf_domain *, em_data);
  */
 static DEFINE_MUTEX(em_pd_mutex);
 
+#ifdef CONFIG_DEBUG_FS
+static struct dentry *rootdir;
+
+static void em_debug_create_cs(struct em_cap_state *cs, struct dentry *pd)
+{
+	struct dentry *d;
+	char name[24];
+
+	snprintf(name, sizeof(name), "cs:%lu", cs->frequency);
+
+	/* Create per-cs directory */
+	d = debugfs_create_dir(name, pd);
+	debugfs_create_ulong("frequency", 0444, d, &cs->frequency);
+	debugfs_create_ulong("power", 0444, d, &cs->power);
+	debugfs_create_ulong("cost", 0444, d, &cs->cost);
+}
+
+static int em_debug_cpus_show(struct seq_file *s, void *unused)
+{
+	seq_printf(s, "%*pbl\n", cpumask_pr_args(to_cpumask(s->private)));
+
+	return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(em_debug_cpus);
+
+static void em_debug_create_pd(struct em_perf_domain *pd, int cpu)
+{
+	struct dentry *d;
+	char name[8];
+	int i;
+
+	snprintf(name, sizeof(name), "pd%d", cpu);
+
+	/* Create the directory of the performance domain */
+	d = debugfs_create_dir(name, rootdir);
+
+	debugfs_create_file("cpus", 0444, d, pd->cpus, &em_debug_cpus_fops);
+
+	/* Create a sub-directory for each capacity state */
+	for (i = 0; i < pd->nr_cap_states; i++)
+		em_debug_create_cs(&pd->table[i], d);
+}
+
+static int __init em_debug_init(void)
+{
+	/* Create /sys/kernel/debug/energy_model directory */
+	rootdir = debugfs_create_dir("energy_model", NULL);
+
+	return 0;
+}
+core_initcall(em_debug_init);
+#else /* CONFIG_DEBUG_FS */
+static void em_debug_create_pd(struct em_perf_domain *pd, int cpu) {}
+#endif
 static struct em_perf_domain *em_create_pd(cpumask_t *span, int nr_states,
 						struct em_data_callback *cb)
 {
@@ -102,6 +157,8 @@ static struct em_perf_domain *em_create_pd(cpumask_t *span, int nr_states,
 	pd->nr_cap_states = nr_states;
 	cpumask_copy(to_cpumask(pd->cpus), span);
 
+	em_debug_create_pd(pd, cpu);
+
 	return pd;
 
 free_cs_table:
diff --git a/kernel/power/qos.c b/kernel/power/qos.c
index b7a82502857a..9d22131afc1e 100644
--- a/kernel/power/qos.c
+++ b/kernel/power/qos.c
@@ -582,10 +582,8 @@ static int register_pm_qos_misc(struct pm_qos_object *qos, struct dentry *d)
 	qos->pm_qos_power_miscdev.name = qos->name;
 	qos->pm_qos_power_miscdev.fops = &pm_qos_power_fops;
 
-	if (d) {
-		(void)debugfs_create_file(qos->name, S_IRUGO, d,
-					  (void *)qos, &pm_qos_debug_fops);
-	}
+	debugfs_create_file(qos->name, S_IRUGO, d, (void *)qos,
+			    &pm_qos_debug_fops);
 
 	return misc_register(&qos->pm_qos_power_miscdev);
 }
@@ -685,8 +683,6 @@ static int __init pm_qos_power_init(void)
 	BUILD_BUG_ON(ARRAY_SIZE(pm_qos_array) != PM_QOS_NUM_CLASSES);
 
 	d = debugfs_create_dir("pm_qos", NULL);
-	if (IS_ERR_OR_NULL(d))
-		d = NULL;
 
 	for (i = PM_QOS_CPU_DMA_LATENCY; i < PM_QOS_NUM_CLASSES; i++) {
 		ret = register_pm_qos_misc(pm_qos_array[i], d);