BIREG_SADR
((csr2 & MS2_ADDR) + MEMRD(BIREG_SADR)) >> 9,
if (bus_space_read_4(ba->ba_iot, ba->ba_ioh, BIREG_SADR) &&
bus_space_read_4(ba->ba_iot, ba->ba_ioh, BIREG_SADR),