EMU_DATA
val = emu_rd(sc, EMU_DATA, 4);
data |= emu_rd(sc, EMU_DATA, 4) & ~mask;
emu_wr(sc, EMU_DATA, data, 4);
val = emu_rd_nolock(sc, EMU_DATA, 4);
data |= emu_rd_nolock(sc, EMU_DATA, 4) & ~mask;
emu_wr_nolock(sc, EMU_DATA, data, 4);
KASSERT(regno != EMU_DATA, ("emu_rd: attempt to read DATA"));