ETXD_B1CNT_SHIFT
desc->bufcnt = cpu_to_be32((s1 << ETXD_B1CNT_SHIFT) |
desc->bufcnt = cpu_to_be32(len << ETXD_B1CNT_SHIFT);
len = (bufcnt & ETXD_B1CNT_MASK) >> ETXD_B1CNT_SHIFT;