MVSW_PORT
swid = mvsw_smi_read(sc, MVSW_PORT(0), MVSW_PORT_SWITCHID);
val = mvsw_smi_read(sc, MVSW_PORT(port), MVSW_PORT_CTRL);
mvsw_smi_write(sc, MVSW_PORT(port), MVSW_PORT_CTRL, val);