XHCI_ERSTBA
xhci_rt_write_8(sc, XHCI_ERSTBA(0), DMAADDR(&sc->sc_eventst_dma, 0));
xhci_rt_write_8(sc, XHCI_ERSTBA(0), 0);
sc->sc_regs.erstba0 = xhci_rt_read_8(sc, XHCI_ERSTBA(0));
xhci_rt_write_8(sc, XHCI_ERSTBA(0), sc->sc_regs.erstba0);