gfe_whack
STATIC int gfe_whack(struct gfe_softc *, enum gfe_whack_op);
error = gfe_whack(sc, GE_WHACK_START);
error = gfe_whack(sc, GE_WHACK_CHANGE);
error = gfe_whack(sc, GE_WHACK_STOP);
error = gfe_whack(sc, GE_WHACK_START);
error = gfe_whack(sc, GE_WHACK_CHANGE);
(void) gfe_whack(sc, GE_WHACK_RESTART);