1 files changed, 20 insertions, 0 deletions

diff --git a/drivers/usb/host/ohci-pci.c b/drivers/usb/host/ohci-pci.c
index d2ba04dd785e..b8a1148f248e 100644
--- a/drivers/usb/host/ohci-pci.c
+++ b/drivers/usb/host/ohci-pci.c
@@ -177,6 +177,13 @@ static int ohci_quirk_amd700(struct usb_hcd *hcd)
                 return 0;
 
         pci_read_config_byte(amd_smbus_dev, PCI_REVISION_ID, &rev);
+
+        /* SB800 needs pre-fetch fix */
+        if ((rev >= 0x40) && (rev <= 0x4f)) {
+                ohci->flags |= OHCI_QUIRK_AMD_PREFETCH;
+                ohci_dbg(ohci, "enabled AMD prefetch quirk\n");
+        }
+
         if ((rev > 0x3b) || (rev < 0x30)) {
                 pci_dev_put(amd_smbus_dev);
                 amd_smbus_dev = NULL;
@@ -262,6 +269,19 @@ static void amd_iso_dev_put(void)
 
 }
 
+static void sb800_prefetch(struct ohci_hcd *ohci, int on)
+{
+        struct pci_dev *pdev;
+        u16 misc;
+
+        pdev = to_pci_dev(ohci_to_hcd(ohci)->self.controller);
+        pci_read_config_word(pdev, 0x50, &misc);
+        if (on == 0)
+                pci_write_config_word(pdev, 0x50, misc & 0xfcff);
+        else
+                pci_write_config_word(pdev, 0x50, misc | 0x0300);
+}
+
 /* List of quirks for OHCI */
 static const struct pci_device_id ohci_pci_quirks[] = {
         {