BWN_TX_SLOTS_PER_FRAME
bwn_dma_freeslot(dr) < BWN_TX_SLOTS_PER_FRAME) {
&(txhdr_cache[(slot / BWN_TX_SLOTS_PER_FRAME) * BWN_HDRSIZE(mac)])
KASSERT(BWN_TXRING_SLOTS % BWN_TX_SLOTS_PER_FRAME == 0,
(dr->dr_numslots / BWN_TX_SLOTS_PER_FRAME) *
KASSERT(bwn_dma_freeslot(dr) >= BWN_TX_SLOTS_PER_FRAME,