PCI: Explicitly put devices into D0 when initializing

AMD BIOS team has root caused an issue that NVMe storage failed to come
back from suspend to a lack of a call to _REG when NVMe device was probed.

112a7f9 ("PCI/ACPI: Call _REG when transitioning D-states") added
support for calling _REG when transitioning D-states, but this only works
if the device actually "transitions" D-states.

967577b ("PCI/PM: Keep runtime PM enabled for unbound PCI devices")
added support for runtime PM on PCI devices, but never actually
'explicitly' sets the device to D0.

To make sure that devices are in D0 and that platform methods such as
_REG are called, explicitly set all devices into D0 during initialization.

Fixes: 967577b ("PCI/PM: Keep runtime PM enabled for unbound PCI devices")
Signed-off-by: Mario Limonciello <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
Tested-by: Denis Benato <[email protected]>
Tested-By: Yijun Shen <[email protected]>
Tested-By: David Perry <[email protected]>
Reviewed-by: Rafael J. Wysocki <[email protected]>
Link: https://patch.msgid.link/[email protected]

Author: superm1

drivers/pci/pci-driver.c

@@ -555,12 +555,6 @@ static void pci_pm_default_resume(struct pci_dev *pci_dev)
 	pci_enable_wake(pci_dev, PCI_D0, false);
 }
 
-static void pci_pm_power_up_and_verify_state(struct pci_dev *pci_dev)
-{
-	pci_power_up(pci_dev);
-	pci_update_current_state(pci_dev, PCI_D0);
-}
-
 static void pci_pm_default_resume_early(struct pci_dev *pci_dev)
 {
 	pci_pm_power_up_and_verify_state(pci_dev);

drivers/pci/pci.c

@@ -3192,6 +3192,12 @@ void pci_d3cold_disable(struct pci_dev *dev)
 }
 EXPORT_SYMBOL_GPL(pci_d3cold_disable);
 
+void pci_pm_power_up_and_verify_state(struct pci_dev *pci_dev)
+{
+	pci_power_up(pci_dev);
+	pci_update_current_state(pci_dev, PCI_D0);
+}
+
 /**
  * pci_pm_init - Initialize PM functions of given PCI device
  * @dev: PCI device to handle.
@@ -3202,9 +3208,6 @@ void pci_pm_init(struct pci_dev *dev)
 	u16 status;
 	u16 pmc;
 
-	pm_runtime_forbid(&dev->dev);
-	pm_runtime_set_active(&dev->dev);
-	pm_runtime_enable(&dev->dev);
 	device_enable_async_suspend(&dev->dev);
 	dev->wakeup_prepared = false;
 
@@ -3266,6 +3269,10 @@ void pci_pm_init(struct pci_dev *dev)
 	pci_read_config_word(dev, PCI_STATUS, &status);
 	if (status & PCI_STATUS_IMM_READY)
 		dev->imm_ready = 1;
+	pci_pm_power_up_and_verify_state(dev);
+	pm_runtime_forbid(&dev->dev);
+	pm_runtime_set_active(&dev->dev);
+	pm_runtime_enable(&dev->dev);
 }
 
 static unsigned long pci_ea_flags(struct pci_dev *dev, u8 prop)

drivers/pci/pci.h

@@ -148,6 +148,7 @@ void pci_dev_adjust_pme(struct pci_dev *dev);
 void pci_dev_complete_resume(struct pci_dev *pci_dev);
 void pci_config_pm_runtime_get(struct pci_dev *dev);
 void pci_config_pm_runtime_put(struct pci_dev *dev);
+void pci_pm_power_up_and_verify_state(struct pci_dev *pci_dev);
 void pci_pm_init(struct pci_dev *dev);
 void pci_ea_init(struct pci_dev *dev);
 void pci_msi_init(struct pci_dev *dev);