Commit 0ce74a3b authored by Rafael J. Wysocki's avatar Rafael J. Wysocki Committed by Bjorn Helgaas
Browse files

PCI/PM: Do not restore BARs if device is not in D0 

Do not attempt to restore the device's BARs in
pci_set_full_power_state() if the actual current
power state of the device is not D0.

Link: https://lore.kernel.org/r/1849718.CQOukoFCf9@kreacher


Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: default avatarBjorn Helgaas <bhelgaas@google.com>
parent e200904b

drivers/pci/pci.c

+16 −16
Original line number Diff line number Diff line
@@ -1273,10 +1273,10 @@ static int pci_set_full_power_state(struct pci_dev *dev) 


	pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);

	dev->current_state = pmcsr & PCI_PM_CTRL_STATE_MASK;

	if (dev->current_state != PCI_D0)

	if (dev->current_state != PCI_D0) {

		pci_info_ratelimited(dev, "Refused to change power state from %s to D0\n",

				     pci_power_name(dev->current_state));



	} else if (ret > 0) {

		/*

		 * According to section 5.4.1 of the "PCI BUS POWER MANAGEMENT

		 * INTERFACE SPECIFICATION, REV. 1.2", a device transitioning
@@ -1290,8 +1290,8 @@ static int pci_set_full_power_state(struct pci_dev *dev) 
		 * restore at least the BARs so that the device will be

		 * accessible to its driver.

		 */

	if (ret > 0)

		pci_restore_bars(dev);

	}



	if (dev->bus->self)

		pcie_aspm_pm_state_change(dev->bus->self);