[PATCH 4.5 017/200] usb: host: xhci-plat: fix cannot work if R-Car Gen2/3 run on above 4GB phys

[Greg Kroah-Hartman]

4.5-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Yoshihiro Shimoda <yoshihiro.shimoda.uh@xxxxxxxxxxx>

commit 5ad3b03e4910f9f62342956ecdc758c7af6b8699 upstream.

This patch fixes an issue that cannot work if R-Car Gen2/3 run on
above 4GB physical memory environment to use a quirk XHCI_NO_64BIT_SUPPORT.

Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@xxxxxxxxxxx>
Reviewed-by: Felipe Balbi <felipe.balbi@xxxxxxxxxxxxxxx>
Signed-off-by: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/usb/host/xhci-plat.c |   13 +++++++++++++
 1 file changed, 13 insertions(+)

--- a/drivers/usb/host/xhci-plat.c
+++ b/drivers/usb/host/xhci-plat.c
@@ -39,12 +39,25 @@ static const struct xhci_driver_override
 
 static void xhci_plat_quirks(struct device *dev, struct xhci_hcd *xhci)
 {
+	struct usb_hcd *hcd = xhci_to_hcd(xhci);
+
 	/*
 	 * As of now platform drivers don't provide MSI support so we ensure
 	 * here that the generic code does not try to make a pci_dev from our
 	 * dev struct in order to setup MSI
 	 */
 	xhci->quirks |= XHCI_PLAT;
+
+	/*
+	 * On R-Car Gen2 and Gen3, the AC64 bit (bit 0) of HCCPARAMS1 is set
+	 * to 1. However, these SoCs don't support 64-bit address memory
+	 * pointers. So, this driver clears the AC64 bit of xhci->hcc_params
+	 * to call dma_set_coherent_mask(dev, DMA_BIT_MASK(32)) in
+	 * xhci_gen_setup().
+	 */
+	if (xhci_plat_type_is(hcd, XHCI_PLAT_TYPE_RENESAS_RCAR_GEN2) ||
+	    xhci_plat_type_is(hcd, XHCI_PLAT_TYPE_RENESAS_RCAR_GEN3))
+		xhci->quirks |= XHCI_NO_64BIT_SUPPORT;
 }
 
 /* called during probe() after chip reset completes */