USABLE_TX_BD
MCLBYTES * BNX_MAX_SEGMENTS, USABLE_TX_BD,
sc->max_tx_bd = USABLE_TX_BD;
DBRUNIF(1, sc->tx_hi_watermark = USABLE_TX_BD);
bnx_dump_tx_mbuf_chain(sc, 0, USABLE_TX_BD);
bnx_dump_tx_chain(sc, 0, USABLE_TX_BD);
IFQ_SET_MAXLEN(&ifp->if_snd, USABLE_TX_BD - 1);