TSIZ_PKTCNT_SHIFT
hctsiz |= 1 << TSIZ_PKTCNT_SHIFT;
hctsiz |= num_packets << TSIZ_PKTCNT_SHIFT & TSIZ_PKTCNT_MASK;
TSIZ_PKTCNT_SHIFT);
(hctsiz & TSIZ_PKTCNT_MASK) >> TSIZ_PKTCNT_SHIFT);
count = (hctsiz & TSIZ_PKTCNT_MASK) >> TSIZ_PKTCNT_SHIFT;