[PATCH] USB: EHCI works again on NVidia controllers with >2GB RAM

From: Paul Serice <paul@serice.net>

The workaround in commit f7201c3dcd7799f2aa3d6ec427b194225360ecee
broke.  The work around requires memory for DMA transfers for some
NVidia EHCI controllers to be below 2GB, but recent changes have
caused some DMA memory to be allocated before the DMA mask is set.

Signed-off-by: Paul Serice <paul@serice.net>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/usb/host/ehci-pci.c

@@ -76,6 +76,30 @@ static int ehci_pci_setup(struct usb_hcd *hcd)
 	dbg_hcs_params(ehci, "reset");
 	dbg_hcc_params(ehci, "reset");
 
+        /* ehci_init() causes memory for DMA transfers to be
+         * allocated.  Thus, any vendor-specific workarounds based on
+         * limiting the type of memory used for DMA transfers must
+         * happen before ehci_init() is called. */
+	switch (pdev->vendor) {
+	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;
+	}
+
 	/* cache this readonly data; minimize chip reads */
 	ehci->hcs_params = readl(&ehci->caps->hcs_params);
 
@@ -88,8 +112,6 @@ static int ehci_pci_setup(struct usb_hcd *hcd)
 	if (retval)
 		return retval;
 
-	/* NOTE:  only the parts below this line are PCI-specific */
-
 	switch (pdev->vendor) {
 	case PCI_VENDOR_ID_TDI:
 		if (pdev->device == PCI_DEVICE_ID_TDI_EHCI) {
@@ -107,19 +129,6 @@ static int ehci_pci_setup(struct usb_hcd *hcd)
 		break;
 	case PCI_VENDOR_ID_NVIDIA:
 		switch (pdev->device) {
-		/* NVidia reports that certain chips don't handle
-		 * QH, ITD, or SITD addresses above 2GB.  (But TD,
-		 * data buffer, and periodic schedule are normal.)
-		 */
-		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;
 		/* Some NForce2 chips have problems with selective suspend;
 		 * fixed in newer silicon.
 		 */