uhci: Enable "depth" tree traversal for bulk transfers

Set the "depth" flag on bulk transactions.  Since SeaBIOS doesn't use
bandwidth reclamation, without the depth flag the uhci controller will
only transfer one bulk packet per 1 ms frame.  This results in a
maximum of 64 bytes per millisecond, which severely limits the
transfer rate.

Signed-off-by: Kevin O'Connor <kevin@koconnor.net>

diff --git a/src/hw/usb-uhci.c b/src/hw/usb-uhci.c
index 6dcc3401d5800adfe4e558db7c5a7d39c9ff37bf..7ef50d118c912ecf3817fc07844e9a93cc665bff 100644 (file)
--- a/src/hw/usb-uhci.c
+++ b/src/hw/usb-uhci.c
@@ -537,9 +537,9 @@ uhci_send_bulk(struct usb_pipe *p, int dir, void *data, int datasize)
         int transfer = datasize;
         if (transfer > maxpacket)
             transfer = maxpacket;
-        struct uhci_td *nexttd_fl = MAKE_FLATPTR(GET_SEG(SS)
-                                                 , &tds[tdpos % STACKTDS]);
-        td->link = (transfer==datasize ? UHCI_PTR_TERM : (u32)nexttd_fl);
+        u32 nexttd = (u32)MAKE_FLATPTR(GET_SEG(SS), &tds[tdpos % STACKTDS]);
+        td->link = (transfer==datasize
+                    ? UHCI_PTR_TERM : (nexttd | UHCI_PTR_DEPTH));
         td->token = (uhci_explen(transfer) | toggle
                      | (devaddr << TD_TOKEN_DEVADDR_SHIFT)
                      | (dir ? USB_PID_IN : USB_PID_OUT));