SIOP_SIST0
sist = readw(adp->addr + SIOP_SIST0);
if (o == SIOP_SIST0) {
reg = siop_sgc_r1(v, h, SIOP_SIST0);
if (o == SIOP_SIST0) {
reg = siop_gsc_r1(v, h, SIOP_SIST0);
sist = readw(adp->addr + SIOP_SIST0);
SIOP_SIST0);
SIOP_SIST0);
(void)bus_space_read_1(sc->sc_rt, sc->sc_rh, SIOP_SIST0);