IG4_REG_CTL
reg_write(sc, IG4_REG_CTL,
REGDUMP(sc, IG4_REG_CTL);
ctl = reg_read(sc, IG4_REG_CTL);
reg_write(sc, IG4_REG_CTL, ctl);
sc->cfg.bus_speed = reg_read(sc, IG4_REG_CTL) & IG4_CTL_SPEED_MASK;