DDMA_CTRL_REG
DMA_WRITE(sc, DDMA_CTRL_REG(ch->ch_index), cfg | DDMA_CTRL_LOAD);
val = DMA_READ(sc, DDMA_CTRL_REG(ch->ch_index));
DMA_WRITE(sc, DDMA_CTRL_REG(ch->ch_index), val);
DMA_WRITE(sc, DDMA_CTRL_REG(index), 0);