FBNIC_RXB_PAUSE_DROP_CTRL
wr32(fbd, FBNIC_RXB_PAUSE_DROP_CTRL,
rxb_pause_ctrl = rd32(fbd, FBNIC_RXB_PAUSE_DROP_CTRL);
wr32(fbd, FBNIC_RXB_PAUSE_DROP_CTRL, rxb_pause_ctrl);
reg = rd32(fbd, FBNIC_RXB_PAUSE_DROP_CTRL);
wr32(fbd, FBNIC_RXB_PAUSE_DROP_CTRL, reg);