[AGPGART] Suspend/Resume support for AMD64 GART.

This adds support for suspend/resume to the amd64-agp driver. Without
it, X displays garbage after resume from swsusp.
Signed-off-by: Michal Schmidt <xschmi00@stud.feec.vutbr.cz>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Dave Jones <davej@redhat.com>

drivers/char/agp/amd64-agp.c

@@ -600,6 +600,26 @@ static void __devexit agp_amd64_remove(struct pci_dev *pdev)
 	agp_put_bridge(bridge);
 }
 
+#ifdef CONFIG_PM
+
+static int agp_amd64_suspend(struct pci_dev *pdev, pm_message_t state)
+{
+	pci_save_state(pdev);
+	pci_set_power_state(pdev, pci_choose_state(pdev, state));
+
+	return 0;
+}
+
+static int agp_amd64_resume(struct pci_dev *pdev)
+{
+	pci_set_power_state(pdev, PCI_D0);
+	pci_restore_state(pdev);
+
+	return amd_8151_configure();
+}
+
+#endif /* CONFIG_PM */
+
 static struct pci_device_id agp_amd64_pci_table[] = {
 	{
 	.class		= (PCI_CLASS_BRIDGE_HOST << 8),
@@ -718,6 +738,10 @@ static struct pci_driver agp_amd64_pci_driver = {
 	.id_table	= agp_amd64_pci_table,
 	.probe		= agp_amd64_probe,
 	.remove		= agp_amd64_remove,
+#ifdef CONFIG_PM
+	.suspend	= agp_amd64_suspend,
+	.resume		= agp_amd64_resume,
+#endif
 };