GMAC_CHAN_TX_CONTROL
reg = dwqe_read(sc, GMAC_CHAN_TX_CONTROL(0));
dwqe_write(sc, GMAC_CHAN_TX_CONTROL(0), reg);
mode = dwqe_read(sc, GMAC_CHAN_TX_CONTROL(0));
dwqe_write(sc, GMAC_CHAN_TX_CONTROL(0), mode);
reg = dwqe_read(sc, GMAC_CHAN_TX_CONTROL(0));
dwqe_write(sc, GMAC_CHAN_TX_CONTROL(0), reg);