ssdfb_set_range
void ssdfb_set_range(struct ssdfb_softc *, uint8_t, uint8_t,
ssdfb_set_range(sc, 0, sc->sc_width - 1,
ssdfb_set_range(sc, x1, x2 - 1, y1 / 8, (y2 / 8) - 1);