PDC_DMA_BUF_MAX
cnt += ((sg->length / PDC_DMA_BUF_MAX) + 1);
while (bufcnt > PDC_DMA_BUF_MAX) {
pdc_build_txd(pdcs, databufptr, PDC_DMA_BUF_MAX,
bufcnt -= PDC_DMA_BUF_MAX;
databufptr += PDC_DMA_BUF_MAX;
while (bufcnt > PDC_DMA_BUF_MAX) {
pdc_build_rxd(pdcs, databufptr, PDC_DMA_BUF_MAX, flags);
bufcnt -= PDC_DMA_BUF_MAX;
databufptr += PDC_DMA_BUF_MAX;