PCI: Explicitly put devices into D0 when initializing

JIRA: https://issues.redhat.com/browse/RHEL-90801
Upstream Status: 4d4c10f

commit 4d4c10f
Author: Mario Limonciello <mario.limonciello@amd.com>
Date:   Wed Apr 23 23:31:32 2025 -0500

    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 <mario.limonciello@amd.com>
    Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
    Tested-by: Denis Benato <benato.denis96@gmail.com>
    Tested-By: Yijun Shen <Yijun_Shen@Dell.com>
    Tested-By: David Perry <david.perry@amd.com>
    Reviewed-by: Rafael J. Wysocki <rafael@kernel.org>
    Link: https://patch.msgid.link/20250424043232.1848107-1-superm1@kernel.org

Signed-off-by: Myron Stowe <mstowe@redhat.com>

Author: Myron Stowe

drivers/pci/pci-driver.c

@@ -564,12 +564,6 @@ 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);