[PATCH] USB: EHCI workaround for NForce and mem > 2GB

NVidia reports (via Mark Overby) that some of their EHCI controllers
don't like certain data structure addresses beyond the 2GB mark.
He provided an earlier version of this patch.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/usb/host/ehci-hcd.c b/drivers/usb/host/ehci-hcd.c
index 2f7037c..ae5ba4d 100644
--- a/drivers/usb/host/ehci-hcd.c
+++ b/drivers/usb/host/ehci-hcd.c
@@ -400,6 +400,23 @@
 				return -EIO;
 			}
 			break;
+		case PCI_VENDOR_ID_NVIDIA:
+			/* NVidia reports that certain chips don't handle
+			 * QH, ITD, or SITD addresses above 2GB.  (But TD,
+			 * data buffer, and periodic schedule are normal.)
+			 */
+			switch (pdev->device) {
+			case 0x003c:	/* MCP04 */
+			case 0x005b:	/* CK804 */
+			case 0x00d8:	/* CK8 */
+			case 0x00e8:	/* CK8S */
+				if (pci_set_consistent_dma_mask(pdev,
+							DMA_31BIT_MASK) < 0)
+					ehci_warn (ehci, "can't enable NVidia "
+						"workaround for >2GB RAM\n");
+				break;
+			}
+			break;
 		}
 
 		/* optional debug port, normally in the first BAR */