NPE_TXBUF
error = npe_dma_setup(sc, &sc->txdma, "tx", NPE_TXBUF, NPE_MAXSEG);
ixpqmgr_qconfig(sc->tx_qid, NPE_TXBUF, 0, NPE_TXBUF, 0, NULL, sc);
ixpqmgr_qconfig(sc->tx_doneqid, NPE_TXBUF, 0, 2,