DMA_IntMask
tc_writel(tc_readl(&tr->DMA_Ctl) | DMA_IntMask, &tr->DMA_Ctl);
if (!(dmactl & DMA_IntMask)) {
tc_writel(dmactl | DMA_IntMask, &tr->DMA_Ctl);
tc_writel(tc_readl(&tr->DMA_Ctl) & ~DMA_IntMask, &tr->DMA_Ctl);