usb: host: xhci-plat: fix cannot work if R-Car Gen2/3 run on above 4GB phys

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.

Cc: <stable@vger.kernel.org>
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Reviewed-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 13 insertions, 0 deletions

diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c
index 5c15e9bc5f7a..474b5fa14900 100644
--- a/drivers/usb/host/xhci-plat.c
+++ b/drivers/usb/host/xhci-plat.c
@@ -39,12 +39,25 @@ static const struct xhci_driver_overrides xhci_plat_overrides __initconst = {
 
 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 */