TI_TX_RING_BASE
CSR_WRITE_4(sc, TI_WINBASE, TI_TX_RING_BASE);
TI_HOSTADDR(rcb->ti_hostaddr) = TI_TX_RING_BASE;
ti_mem_read(sc, TI_TX_RING_BASE + idx * sizeof(txdesc),
ti_mem_write(sc, TI_TX_RING_BASE + frag * sizeof(txdesc),
ti_mem_write(sc, TI_TX_RING_BASE + cur * sizeof(txdesc),