IGC_TQAVCTRL_TRANSMIT_MODE_TSN
return !!(rd32(IGC_TQAVCTRL) & IGC_TQAVCTRL_TRANSMIT_MODE_TSN);
tqavctrl &= ~(IGC_TQAVCTRL_TRANSMIT_MODE_TSN |
tqavctrl |= IGC_TQAVCTRL_TRANSMIT_MODE_TSN | IGC_TQAVCTRL_ENHANCED_QAV;