Commit a6cbaade authored Aug 08, 2013 by Alex Williamson Committed by Bjorn Helgaas Aug 14, 2013

PCI: Wake-up devices before saving config space for reset



Devices come out of reset in D0.  Restoring a device to a different
post-reset state takes more smarts than our simple config space
restore, which can leave devices in an inconsistent state.  For
example, if a device is reset in D3, but the restore doesn't
successfully return the device to D3, then the actual state of the
device and dev->current_state are contradictory.  Put everything
in D0 going into the reset, then we don't need to do anything
special on the way out.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

parent 090a3c53

drivers/pci/pci.c

+7 −0

Original line number	Diff line number	Diff line
		@@ -3332,6 +3332,13 @@ static void pci_dev_unlock(struct pci_dev *dev)

		static void pci_dev_save_and_disable(struct pci_dev *dev)
		{
		/*
		* Wake-up device prior to save. PM registers default to D0 after
		* reset and a simple register restore doesn't reliably return
		* to a non-D0 state anyway.
		*/
		pci_set_power_state(dev, PCI_D0);

		pci_save_state(dev);
		/*
		* Disable the device by clearing the Command register, except for