- Update Xen patches to 3.3-rc5 and c/s 1157.

[linux-flexiantxendom0-3.2.10.git] / drivers / xen / xen-pciback / conf_space_capability.c

diff --git a/drivers/xen/xen-pciback/conf_space_capability.c b/drivers/xen/xen-pciback/conf_space_capability.c
index 7f83e90..89d6e90 100644 (file)
--- a/drivers/xen/xen-pciback/conf_space_capability.c
+++ b/drivers/xen/xen-pciback/conf_space_capability.c
@@ -140,6 +140,21 @@ static int pm_ctrl_write(struct pci_dev *dev, int offset, u16 new_value,
                goto out;
        }
 
+#ifdef CONFIG_XEN
+       /*
+        * Device may lose PCI config info on D3->D0 transition. This
+        * is a problem for some guests which will not reset BARs. Even
+        * those that have a go will be foiled by our BAR-write handler
+        * which will discard the write! Since Linux won't re-init
+        * the config space automatically in all cases, we do it here.
+        * Future: Should we re-initialise all first 64 bytes of config space?
+        */
+       if (new_state == PCI_D0 &&
+           (old_state == PCI_D3hot || old_state == PCI_D3cold) &&
+           !(old_value & PCI_PM_CTRL_NO_SOFT_RESET))
+               pci_restore_bars(dev);
+#endif
+
  out:
        return err;
 }