Merge tag 'pm-4.18-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull more power management updates from Rafael Wysocki:
 "These revert a recent PM core change that introduced a regression, fix
  the build when the recently added Kryo cpufreq driver is selected, add
  support for devices attached to multiple power domains to the generic
  power domains (genpd) framework, add support for iowait boosting on
  systens with hardware-managed P-states (HWP) enabled to the
  intel_pstate driver, modify the behavior of the wakeup_count device
  attribute in sysfs, fix a few issues and clean up some ugliness,
  mostly in cpufreq (core and drivers) and in the cpupower utility.

  Specifics:

   - Revert a recent PM core change that attempted to fix an issue
     related to device links, but introduced a regression (Rafael
     Wysocki)

   - Fix build when the recently added cpufreq driver for Kryo
     processors is selected by making it possible to build that driver
     as a module (Arnd Bergmann)

   - Fix the long idle detection mechanism in the out-of-band (ondemand
     and conservative) cpufreq governors (Chen Yu)

   - Add support for devices in multiple power domains to the generic
     power domains (genpd) framework (Ulf Hansson)

   - Add support for iowait boosting on systems with hardware-managed
     P-states (HWP) enabled to the intel_pstate driver and make it use
     that feature on systems with Skylake Xeon processors as it is
     reported to improve performance significantly on those systems
     (Srinivas Pandruvada)

   - Fix and update the acpi_cpufreq, ti-cpufreq and imx6q cpufreq
     drivers (Colin Ian King, Suman Anna, Sébastien Szymanski)

   - Change the behavior of the wakeup_count device attribute in sysfs
     to expose the number of events when the device might have aborted
     system suspend in progress (Ravi Chandra Sadineni)

   - Fix two minor issues in the cpupower utility (Abhishek Goel, Colin
     Ian King)"

* tag 'pm-4.18-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  Revert "PM / runtime: Fixup reference counting of device link suppliers at probe"
  cpufreq: imx6q: check speed grades for i.MX6ULL
  cpufreq: governors: Fix long idle detection logic in load calculation
  cpufreq: intel_pstate: enable boost for Skylake Xeon
  PM / wakeup: Export wakeup_count instead of event_count via sysfs
  PM / Domains: Add dev_pm_domain_attach_by_id() to manage multi PM domains
  PM / Domains: Add support for multi PM domains per device to genpd
  PM / Domains: Split genpd_dev_pm_attach()
  PM / Domains: Don't attach devices in genpd with multi PM domains
  PM / Domains: dt: Allow power-domain property to be a list of specifiers
  cpufreq: intel_pstate: New sysfs entry to control HWP boost
  cpufreq: intel_pstate: HWP boost performance on IO wakeup
  cpufreq: intel_pstate: Add HWP boost utility and sched util hooks
  cpufreq: ti-cpufreq: Use devres managed API in probe()
  cpufreq: ti-cpufreq: Fix an incorrect error return value
  cpufreq: ACPI: make function acpi_cpufreq_fast_switch() static
  cpufreq: kryo: allow building as a loadable module
  cpupower : Fix header name to read idle state name
  cpupower: fix spelling mistake: "logilename" -> "logfilename"

5 files changed, 181 insertions, 28 deletions

diff --git a/drivers/base/dd.c b/drivers/base/dd.c
index fb4e2df..1435d72 100644
--- a/drivers/base/dd.c
+++ b/drivers/base/dd.c
@@ -580,7 +580,7 @@ int driver_probe_device(struct device_driver *drv, struct device *dev)
 	pr_debug("bus: '%s': %s: matched device %s with driver %s\n",
 		 drv->bus->name, __func__, dev_name(dev), drv->name);
 
-	pm_runtime_resume_suppliers(dev);
+	pm_runtime_get_suppliers(dev);
 	if (dev->parent)
 		pm_runtime_get_sync(dev->parent);
 
@@ -591,6 +591,7 @@ int driver_probe_device(struct device_driver *drv, struct device *dev)
 	if (dev->parent)
 		pm_runtime_put(dev->parent);
 
+	pm_runtime_put_suppliers(dev);
 	return ret;
 }
 
diff --git a/drivers/base/power/common.c b/drivers/base/power/common.c
index 7ae62b6..df41b47 100644
--- a/drivers/base/power/common.c
+++ b/drivers/base/power/common.c
@@ -117,13 +117,50 @@ int dev_pm_domain_attach(struct device *dev, bool power_on)
 EXPORT_SYMBOL_GPL(dev_pm_domain_attach);
 
 /**
+ * dev_pm_domain_attach_by_id - Associate a device with one of its PM domains.
+ * @dev: The device used to lookup the PM domain.
+ * @index: The index of the PM domain.
+ *
+ * As @dev may only be attached to a single PM domain, the backend PM domain
+ * provider creates a virtual device to attach instead. If attachment succeeds,
+ * the ->detach() callback in the struct dev_pm_domain are assigned by the
+ * corresponding backend attach function, as to deal with detaching of the
+ * created virtual device.
+ *
+ * This function should typically be invoked by a driver during the probe phase,
+ * in case its device requires power management through multiple PM domains. The
+ * driver may benefit from using the received device, to configure device-links
+ * towards its original device. Depending on the use-case and if needed, the
+ * links may be dynamically changed by the driver, which allows it to control
+ * the power to the PM domains independently from each other.
+ *
+ * Callers must ensure proper synchronization of this function with power
+ * management callbacks.
+ *
+ * Returns the virtual created device when successfully attached to its PM
+ * domain, NULL in case @dev don't need a PM domain, else an ERR_PTR().
+ * Note that, to detach the returned virtual device, the driver shall call
+ * dev_pm_domain_detach() on it, typically during the remove phase.
+ */
+struct device *dev_pm_domain_attach_by_id(struct device *dev,
+					  unsigned int index)
+{
+	if (dev->pm_domain)
+		return ERR_PTR(-EEXIST);
+
+	return genpd_dev_pm_attach_by_id(dev, index);
+}
+EXPORT_SYMBOL_GPL(dev_pm_domain_attach_by_id);
+
+/**
  * dev_pm_domain_detach - Detach a device from its PM domain.
  * @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 thus
- * try to detach the @dev from its PM domain. Typically it should be invoked
- * from subsystem level code during the remove phase.
+ * 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.
  *
  * 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 6f403d6..4925af5 100644
--- a/drivers/base/power/domain.c
+++ b/drivers/base/power/domain.c
@@ -2171,6 +2171,15 @@ struct generic_pm_domain *of_genpd_remove_last(struct device_node *np)
 }
 EXPORT_SYMBOL_GPL(of_genpd_remove_last);
 
+static void genpd_release_dev(struct device *dev)
+{
+	kfree(dev);
+}
+
+static struct bus_type genpd_bus_type = {
+	.name		= "genpd",
+};
+
 /**
  * genpd_dev_pm_detach - Detach a device from its PM domain.
  * @dev: Device to detach.
@@ -2208,6 +2217,10 @@ static void genpd_dev_pm_detach(struct device *dev, bool power_off)
 
 	/* Check if PM domain can be powered off after removing this device. */
 	genpd_queue_power_off_work(pd);
+
+	/* Unregister the device if it was created by genpd. */
+	if (dev->bus == &genpd_bus_type)
+		device_unregister(dev);
 }
 
 static void genpd_dev_pm_sync(struct device *dev)
@@ -2221,32 +2234,17 @@ static void genpd_dev_pm_sync(struct device *dev)
 	genpd_queue_power_off_work(pd);
 }
 
-/**
- * genpd_dev_pm_attach - Attach a device to its PM domain using DT.
- * @dev: Device to attach.
- *
- * Parse device's OF node to find a PM domain specifier. If such is found,
- * attaches the device to retrieved pm_domain ops.
- *
- * Returns 1 on successfully attached PM domain, 0 when the device don't need a
- * PM domain or a negative error code in case of failures. Note that if a
- * power-domain exists for the device, but it cannot be found or turned on,
- * then return -EPROBE_DEFER to ensure that the device is not probed and to
- * re-try again later.
- */
-int genpd_dev_pm_attach(struct device *dev)
+static int __genpd_dev_pm_attach(struct device *dev, struct device_node *np,
+				 unsigned int index)
 {
 	struct of_phandle_args pd_args;
 	struct generic_pm_domain *pd;
 	int ret;
 
-	if (!dev->of_node)
-		return 0;
-
-	ret = of_parse_phandle_with_args(dev->of_node, "power-domains",
-					"#power-domain-cells", 0, &pd_args);
+	ret = of_parse_phandle_with_args(np, "power-domains",
+				"#power-domain-cells", index, &pd_args);
 	if (ret < 0)
-		return 0;
+		return ret;
 
 	mutex_lock(&gpd_list_lock);
 	pd = genpd_get_from_provider(&pd_args);
@@ -2282,8 +2280,98 @@ int genpd_dev_pm_attach(struct device *dev)
 
 	return ret ? -EPROBE_DEFER : 1;
 }
+
+/**
+ * genpd_dev_pm_attach - Attach a device to its PM domain using DT.
+ * @dev: Device to attach.
+ *
+ * Parse device's OF node to find a PM domain specifier. If such is found,
+ * attaches the device to retrieved pm_domain ops.
+ *
+ * Returns 1 on successfully attached PM domain, 0 when the device don't need a
+ * PM domain or when multiple power-domains exists for it, else a negative error
+ * code. Note that if a power-domain exists for the device, but it cannot be
+ * found or turned on, then return -EPROBE_DEFER to ensure that the device is
+ * not probed and to re-try again later.
+ */
+int genpd_dev_pm_attach(struct device *dev)
+{
+	if (!dev->of_node)
+		return 0;
+
+	/*
+	 * Devices with multiple PM domains must be attached separately, as we
+	 * can only attach one PM domain per device.
+	 */
+	if (of_count_phandle_with_args(dev->of_node, "power-domains",
+				       "#power-domain-cells") != 1)
+		return 0;
+
+	return __genpd_dev_pm_attach(dev, dev->of_node, 0);
+}
 EXPORT_SYMBOL_GPL(genpd_dev_pm_attach);
 
+/**
+ * genpd_dev_pm_attach_by_id - Associate a device with one of its PM domains.
+ * @dev: The device used to lookup the PM domain.
+ * @index: The index of the PM domain.
+ *
+ * Parse device's OF node to find a PM domain specifier at the provided @index.
+ * If such is found, creates a virtual device and attaches it to the retrieved
+ * pm_domain ops. To deal with detaching of the virtual device, the ->detach()
+ * callback in the struct dev_pm_domain are assigned to genpd_dev_pm_detach().
+ *
+ * Returns the created virtual device if successfully attached PM domain, NULL
+ * when the device don't need a PM domain, else an ERR_PTR() in case of
+ * failures. If a power-domain exists for the device, but cannot be found or
+ * turned on, then ERR_PTR(-EPROBE_DEFER) is returned to ensure that the device
+ * is not probed and to re-try again later.
+ */
+struct device *genpd_dev_pm_attach_by_id(struct device *dev,
+					 unsigned int index)
+{
+	struct device *genpd_dev;
+	int num_domains;
+	int ret;
+
+	if (!dev->of_node)
+		return NULL;
+
+	/* Deal only with devices using multiple PM domains. */
+	num_domains = of_count_phandle_with_args(dev->of_node, "power-domains",
+						 "#power-domain-cells");
+	if (num_domains < 2 || index >= num_domains)
+		return NULL;
+
+	/* Allocate and register device on the genpd bus. */
+	genpd_dev = kzalloc(sizeof(*genpd_dev), GFP_KERNEL);
+	if (!genpd_dev)
+		return ERR_PTR(-ENOMEM);
+
+	dev_set_name(genpd_dev, "genpd:%u:%s", index, dev_name(dev));
+	genpd_dev->bus = &genpd_bus_type;
+	genpd_dev->release = genpd_release_dev;
+
+	ret = device_register(genpd_dev);
+	if (ret) {
+		kfree(genpd_dev);
+		return ERR_PTR(ret);
+	}
+
+	/* Try to attach the device to the PM domain at the specified index. */
+	ret = __genpd_dev_pm_attach(genpd_dev, dev->of_node, index);
+	if (ret < 1) {
+		device_unregister(genpd_dev);
+		return ret ? ERR_PTR(ret) : NULL;
+	}
+
+	pm_runtime_set_active(genpd_dev);
+	pm_runtime_enable(genpd_dev);
+
+	return genpd_dev;
+}
+EXPORT_SYMBOL_GPL(genpd_dev_pm_attach_by_id);
+
 static const struct of_device_id idle_state_match[] = {
 	{ .compatible = "domain-idle-state", },
 	{ }
@@ -2443,6 +2531,12 @@ unlock:
 }
 EXPORT_SYMBOL_GPL(of_genpd_opp_to_performance_state);
 
+static int __init genpd_bus_init(void)
+{
+	return bus_register(&genpd_bus_type);
+}
+core_initcall(genpd_bus_init);
+
 #endif /* CONFIG_PM_GENERIC_DOMAINS_OF */
 
 
diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c
index c6030f1..beb85c3 100644
--- a/drivers/base/power/runtime.c
+++ b/drivers/base/power/runtime.c
@@ -1563,16 +1563,37 @@ void pm_runtime_clean_up_links(struct device *dev)
 }
 
 /**
- * pm_runtime_resume_suppliers - Resume supplier devices.
+ * pm_runtime_get_suppliers - Resume and reference-count supplier devices.
  * @dev: Consumer device.
  */
-void pm_runtime_resume_suppliers(struct device *dev)
+void pm_runtime_get_suppliers(struct device *dev)
 {
+	struct device_link *link;
 	int idx;
 
 	idx = device_links_read_lock();
 
-	rpm_get_suppliers(dev);
+	list_for_each_entry_rcu(link, &dev->links.suppliers, c_node)
+		if (link->flags & DL_FLAG_PM_RUNTIME)
+			pm_runtime_get_sync(link->supplier);
+
+	device_links_read_unlock(idx);
+}
+
+/**
+ * pm_runtime_put_suppliers - Drop references to supplier devices.
+ * @dev: Consumer device.
+ */
+void pm_runtime_put_suppliers(struct device *dev)
+{
+	struct device_link *link;
+	int idx;
+
+	idx = device_links_read_lock();
+
+	list_for_each_entry_rcu(link, &dev->links.suppliers, c_node)
+		if (link->flags & DL_FLAG_PM_RUNTIME)
+			pm_runtime_put(link->supplier);
 
 	device_links_read_unlock(idx);
 }
diff --git a/drivers/base/power/sysfs.c b/drivers/base/power/sysfs.c
index 0f651ef..d713738 100644
--- a/drivers/base/power/sysfs.c
+++ b/drivers/base/power/sysfs.c
@@ -353,7 +353,7 @@ static ssize_t wakeup_count_show(struct device *dev,
 
 	spin_lock_irq(&dev->power.lock);
 	if (dev->power.wakeup) {
-		count = dev->power.wakeup->event_count;
+		count = dev->power.wakeup->wakeup_count;
 		enabled = true;
 	}
 	spin_unlock_irq(&dev->power.lock);