TEMAC_GMI_TXCF
tcr = gmi_read_4(TEMAC_GMI_TXCF) & ~GMI_TX_ENABLE;
gmi_write_4(TEMAC_GMI_TXCF, tcr);
tcr = (gmi_read_4(TEMAC_GMI_TXCF) | GMI_TX_ENABLE) &
gmi_write_4(TEMAC_GMI_TXCF, tcr);
tcf = gmi_read_4(TEMAC_GMI_TXCF);
gmi_write_4(TEMAC_GMI_TXCF, tcf & ~GMI_TX_HDX);
gmi_write_4(TEMAC_GMI_TXCF, tcf | GMI_TX_HDX);