DMA_CTRL
HWRITE4(sc, DMA_CTRL, 0);
HSET4(sc, DMA_CTRL, DMA_CTRL_START_STOP_TX_DMA);
HSET4(sc, DMA_CTRL, DMA_CTRL_START_STOP_RX_DMA);
intel_uncore_write_fw(uncore, DMA_CTRL,
ret = intel_wait_for_register_fw(uncore, DMA_CTRL, START_DMA, 0, 100, NULL);
intel_uncore_read_fw(uncore, DMA_CTRL));
intel_uncore_write_fw(uncore, DMA_CTRL, _MASKED_BIT_DISABLE(dma_flags));
MMIO_DH(DMA_CTRL, D_SKL_PLUS, NULL, dma_ctrl_write);
MMIO_D(DMA_CTRL);