Merge branch 'topic/huang-d3cold-v7' into next

* topic/huang-d3cold-v7:
  PCI/PM: add PCIe runtime D3cold support
  PCI: do not call pci_set_power_state with PCI_D3cold
  PCI/PM: add runtime PM support to PCIe port
  ACPI/PM: specify lowest allowed state for device sleep state

1 files changed, 115 insertions, 9 deletions

diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 87928fd..3f8b74f 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -587,7 +587,8 @@ static int pci_raw_set_power_state(struct pci_dev *dev, pci_power_t state)
 		dev_info(&dev->dev, "Refused to change power state, "
 			"currently in D%d\n", dev->current_state);
 
-	/* According to section 5.4.1 of the "PCI BUS POWER MANAGEMENT
+	/*
+	 * According to section 5.4.1 of the "PCI BUS POWER MANAGEMENT
 	 * INTERFACE SPECIFICATION, REV. 1.2", a device transitioning
 	 * from D3hot to D0 _may_ perform an internal reset, thereby
 	 * going to "D0 Uninitialized" rather than "D0 Initialized".
@@ -619,6 +620,16 @@ void pci_update_current_state(struct pci_dev *dev, pci_power_t state)
 	if (dev->pm_cap) {
 		u16 pmcsr;
 
+		/*
+		 * Configuration space is not accessible for device in
+		 * D3cold, so just keep or set D3cold for safety
+		 */
+		if (dev->current_state == PCI_D3cold)
+			return;
+		if (state == PCI_D3cold) {
+			dev->current_state = PCI_D3cold;
+			return;
+		}
 		pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
 		dev->current_state = (pmcsr & PCI_PM_CTRL_STATE_MASK);
 	} else {
@@ -659,8 +670,50 @@ static int pci_platform_power_transition(struct pci_dev *dev, pci_power_t state)
  */
 static void __pci_start_power_transition(struct pci_dev *dev, pci_power_t state)
 {
-	if (state == PCI_D0)
+	if (state == PCI_D0) {
 		pci_platform_power_transition(dev, PCI_D0);
+		/*
+		 * Mandatory power management transition delays, see
+		 * PCI Express Base Specification Revision 2.0 Section
+		 * 6.6.1: Conventional Reset.  Do not delay for
+		 * devices powered on/off by corresponding bridge,
+		 * because have already delayed for the bridge.
+		 */
+		if (dev->runtime_d3cold) {
+			msleep(dev->d3cold_delay);
+			/*
+			 * When powering on a bridge from D3cold, the
+			 * whole hierarchy may be powered on into
+			 * D0uninitialized state, resume them to give
+			 * them a chance to suspend again
+			 */
+			pci_wakeup_bus(dev->subordinate);
+		}
+	}
+}
+
+/**
+ * __pci_dev_set_current_state - Set current state of a PCI device
+ * @dev: Device to handle
+ * @data: pointer to state to be set
+ */
+static int __pci_dev_set_current_state(struct pci_dev *dev, void *data)
+{
+	pci_power_t state = *(pci_power_t *)data;
+
+	dev->current_state = state;
+	return 0;
+}
+
+/**
+ * __pci_bus_set_current_state - Walk given bus and set current state of devices
+ * @bus: Top bus of the subtree to walk.
+ * @state: state to be set
+ */
+static void __pci_bus_set_current_state(struct pci_bus *bus, pci_power_t state)
+{
+	if (bus)
+		pci_walk_bus(bus, __pci_dev_set_current_state, &state);
 }
 
 /**
@@ -672,8 +725,15 @@ static void __pci_start_power_transition(struct pci_dev *dev, pci_power_t state)
  */
 int __pci_complete_power_transition(struct pci_dev *dev, pci_power_t state)
 {
-	return state >= PCI_D0 ?
-			pci_platform_power_transition(dev, state) : -EINVAL;
+	int ret;
+
+	if (state < PCI_D0)
+		return -EINVAL;
+	ret = pci_platform_power_transition(dev, state);
+	/* Power off the bridge may power off the whole hierarchy */
+	if (!ret && state == PCI_D3cold)
+		__pci_bus_set_current_state(dev->subordinate, PCI_D3cold);
+	return ret;
 }
 EXPORT_SYMBOL_GPL(__pci_complete_power_transition);
 
@@ -697,8 +757,8 @@ int pci_set_power_state(struct pci_dev *dev, pci_power_t state)
 	int error;
 
 	/* bound the state we're entering */
-	if (state > PCI_D3hot)
-		state = PCI_D3hot;
+	if (state > PCI_D3cold)
+		state = PCI_D3cold;
 	else if (state < PCI_D0)
 		state = PCI_D0;
 	else if ((state == PCI_D1 || state == PCI_D2) && pci_no_d1d2(dev))
@@ -713,10 +773,15 @@ int pci_set_power_state(struct pci_dev *dev, pci_power_t state)
 
 	/* This device is quirked not to be put into D3, so
 	   don't put it in D3 */
-	if (state == PCI_D3hot && (dev->dev_flags & PCI_DEV_FLAGS_NO_D3))
+	if (state >= PCI_D3hot && (dev->dev_flags & PCI_DEV_FLAGS_NO_D3))
 		return 0;
 
-	error = pci_raw_set_power_state(dev, state);
+	/*
+	 * To put device in D3cold, we put device into D3hot in native
+	 * way, then put device into D3cold with platform ops
+	 */
+	error = pci_raw_set_power_state(dev, state > PCI_D3hot ?
+					PCI_D3hot : state);
 
 	if (!__pci_complete_power_transition(dev, state))
 		error = 0;
@@ -1460,6 +1525,28 @@ void pci_pme_wakeup_bus(struct pci_bus *bus)
 }
 
 /**
+ * pci_wakeup - Wake up a PCI device
+ * @dev: Device to handle.
+ * @ign: ignored parameter
+ */
+static int pci_wakeup(struct pci_dev *pci_dev, void *ign)
+{
+	pci_wakeup_event(pci_dev);
+	pm_request_resume(&pci_dev->dev);
+	return 0;
+}
+
+/**
+ * pci_wakeup_bus - Walk given bus and wake up devices on it
+ * @bus: Top bus of the subtree to walk.
+ */
+void pci_wakeup_bus(struct pci_bus *bus)
+{
+	if (bus)
+		pci_walk_bus(bus, pci_wakeup, NULL);
+}
+
+/**
  * pci_pme_capable - check the capability of PCI device to generate PME#
  * @dev: PCI device to handle.
  * @state: PCI state from which device will issue PME#.
@@ -1480,6 +1567,16 @@ static void pci_pme_list_scan(struct work_struct *work)
 	if (!list_empty(&pci_pme_list)) {
 		list_for_each_entry_safe(pme_dev, n, &pci_pme_list, list) {
 			if (pme_dev->dev->pme_poll) {
+				struct pci_dev *bridge;
+
+				bridge = pme_dev->dev->bus->self;
+				/*
+				 * If bridge is in low power state, the
+				 * configuration space of subordinate devices
+				 * may be not accessible
+				 */
+				if (bridge && bridge->current_state != PCI_D0)
+					continue;
 				pci_pme_wakeup(pme_dev->dev, NULL);
 			} else {
 				list_del(&pme_dev->list);
@@ -1706,6 +1803,10 @@ int pci_prepare_to_sleep(struct pci_dev *dev)
 	if (target_state == PCI_POWER_ERROR)
 		return -EIO;
 
+	/* D3cold during system suspend/hibernate is not supported */
+	if (target_state > PCI_D3hot)
+		target_state = PCI_D3hot;
+
 	pci_enable_wake(dev, target_state, device_may_wakeup(&dev->dev));
 
 	error = pci_set_power_state(dev, target_state);
@@ -1743,12 +1844,16 @@ int pci_finish_runtime_suspend(struct pci_dev *dev)
 	if (target_state == PCI_POWER_ERROR)
 		return -EIO;
 
+	dev->runtime_d3cold = target_state == PCI_D3cold;
+
 	__pci_enable_wake(dev, target_state, true, pci_dev_run_wake(dev));
 
 	error = pci_set_power_state(dev, target_state);
 
-	if (error)
+	if (error) {
 		__pci_enable_wake(dev, target_state, true, false);
+		dev->runtime_d3cold = false;
+	}
 
 	return error;
 }
@@ -1818,6 +1923,7 @@ void pci_pm_init(struct pci_dev *dev)
 
 	dev->pm_cap = pm;
 	dev->d3_delay = PCI_PM_D3_WAIT;
+	dev->d3cold_delay = PCI_PM_D3COLD_WAIT;
 
 	dev->d1_support = false;
 	dev->d2_support = false;