Merge back earlier PM core material for v5.1.

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);

drivers/base/power/clock_ops.c

@@ -65,11 +65,16 @@ 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);
+		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",
+			dev_dbg(dev,
+				"Clock %pC con_id %s managed by runtime PM.\n",
 				ce->clk, ce->con_id);
 		}
+	}
 }
 
 static int __pm_clk_add(struct device *dev, const char *con_id,

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);
 		}

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;
+	u64 now, last, delta;
 
-	delta = now - dev->power.accounting_timestamp;
+	if (dev->power.disable_depth > 0)
+		return;
+
+	last = dev->power.accounting_timestamp;
 
+	now = ktime_get_mono_fast_ns();
 	dev->power.accounting_timestamp = now;
 
-	if (dev->power.disable_depth > 0)
+	/*
+	 * 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;
-
-	last_busy = READ_ONCE(dev->power.last_busy);
+		return 0;
 
-	expires = last_busy + (u64)autosuspend_delay * NSEC_PER_MSEC;
-	if (expires <= now)
-		expires = 0;	/* Already expired. */
+	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 */
 
- 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;

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);

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 (!i915->pmu.sample[__I915_SAMPLE_RC6_ESTIMATED].cur)
-				i915->pmu.suspended_jiffies_last =
-						  kdev->power.suspended_jiffies;
+		if (pm_runtime_status_suspended(kdev)) {
+			val = pm_runtime_suspended_time(kdev);
 
-			val = kdev->power.suspended_jiffies -
-			      i915->pmu.suspended_jiffies_last;
-			val += jiffies - kdev->power.accounting_timestamp;
+			if (!i915->pmu.sample[__I915_SAMPLE_RC6_ESTIMATED].cur)
+				i915->pmu.suspended_time_last = val;
 
-			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);
 	}
 

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.
 	 */

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

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);

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; }