AXI_DMASR
pending = AXIDMA_RD4(sc, AXI_DMASR(AXIDMA_RX_CHAN));
AXIDMA_WR4(sc, AXI_DMASR(AXIDMA_RX_CHAN), pending);
pending = AXIDMA_RD4(sc, AXI_DMASR(AXIDMA_TX_CHAN));
AXIDMA_WR4(sc, AXI_DMASR(AXIDMA_TX_CHAN), pending);