Merge tag 'dmaengine-5.1-rc1' of git://git.infradead.org/users/vkoul/slave-dma

Pull dmaengine updates from Vinod Koul:

 - dmatest updates for modularizing common struct and code

 - remove SG support for VDMA xilinx IP and updates to driver

 - Update to dw driver to support Intel iDMA controllers multi-block
   support

 - tegra updates for proper reporting of residue

 - Add Snow Ridge ioatdma device id and support for IOATDMA v3.4

 - struct_size() usage and useless LIST_HEAD cleanups in subsystem.

 - qDMA controller driver for Layerscape SoCs

 - stm32-dma PM Runtime support

 - And usual updates to imx-sdma, sprd, Documentation, fsl-edma,
   bcm2835, qcom_hidma etc

* tag 'dmaengine-5.1-rc1' of git://git.infradead.org/users/vkoul/slave-dma: (81 commits)
  dmaengine: imx-sdma: fix consistent dma test failures
  dmaengine: imx-sdma: add a test for imx8mq multi sdma devices
  dmaengine: imx-sdma: add clock ratio 1:1 check
  dmaengine: dmatest: move test data alloc & free into functions
  dmaengine: dmatest: add short-hand `buf_size` var in dmatest_func()
  dmaengine: dmatest: wrap src & dst data into a struct
  dmaengine: ioatdma: support latency tolerance report (LTR) for v3.4
  dmaengine: ioatdma: add descriptor pre-fetch support for v3.4
  dmaengine: ioatdma: disable DCA enabling on IOATDMA v3.4
  dmaengine: ioatdma: Add Snow Ridge ioatdma device id
  dmaengine: sprd: Change channel id to slave id for DMA cell specifier
  dt-bindings: dmaengine: sprd: Change channel id to slave id for DMA cell specifier
  dmaengine: mv_xor: Use correct device for DMA API
  Documentation :dmaengine: clarify DMA desc. pointer after submission
  Documentation: dmaengine: fix dmatest.rst warning
  dmaengine: k3dma: Add support for dma-channel-mask
  dmaengine: k3dma: Delete axi_config
  dmaengine: k3dma: Upgrade k3dma driver to support hisi_asp_dma hardware
  Documentation: bindings: dma: Add binding for dma-channel-mask
  Documentation: bindings: k3dma: Extend the k3dma driver binding to support hisi-asp
  ...

1 files changed, 12 insertions, 0 deletions

diff --git a/drivers/dma/ioat/dma.c b/drivers/dma/ioat/dma.c
index 23fb2fa04000..f373a139e0c3 100644
--- a/drivers/dma/ioat/dma.c
+++ b/drivers/dma/ioat/dma.c
@@ -372,6 +372,7 @@ struct ioat_ring_ent **
 ioat_alloc_ring(struct dma_chan *c, int order, gfp_t flags)
 {
 	struct ioatdma_chan *ioat_chan = to_ioat_chan(c);
+	struct ioatdma_device *ioat_dma = ioat_chan->ioat_dma;
 	struct ioat_ring_ent **ring;
 	int total_descs = 1 << order;
 	int i, chunks;
@@ -437,6 +438,17 @@ ioat_alloc_ring(struct dma_chan *c, int order, gfp_t flags)
 	}
 	ring[i]->hw->next = ring[0]->txd.phys;
 
+	/* setup descriptor pre-fetching for v3.4 */
+	if (ioat_dma->cap & IOAT_CAP_DPS) {
+		u16 drsctl = IOAT_CHAN_DRSZ_2MB | IOAT_CHAN_DRS_EN;
+
+		if (chunks == 1)
+			drsctl |= IOAT_CHAN_DRS_AUTOWRAP;
+
+		writew(drsctl, ioat_chan->reg_base + IOAT_CHAN_DRSCTL_OFFSET);
+
+	}
+
 	return ring;
 }