XHCI_MAX_SCRATCHPADS
if (sc->sc_noscratch > XHCI_MAX_SCRATCHPADS) {
struct usb_page_cache scratch_pc[XHCI_MAX_SCRATCHPADS];
struct usb_page scratch_pg[XHCI_MAX_SCRATCHPADS];
volatile uint64_t qwSpBufPtr[XHCI_MAX_SCRATCHPADS];