From: Maxime Ripard <[email protected]>

The addressing mode we were using was not only incrementing the address at
each microblock, but also at each data boundary, which was severely slowing
the transfer, without any benefit since we were not using the data stride.

Switch to the micro block increment only in order to get back to an
acceptable performance level.

Signed-off-by: Maxime Ripard <[email protected]>
Signed-off-by: Ludovic Desroches <[email protected]>
Fixes: 6007ccb57744 ("dmaengine: xdmac: Add interleaved transfer support")
Cc: [email protected] #4.2
---
 drivers/dma/at_xdmac.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/dma/at_xdmac.c b/drivers/dma/at_xdmac.c
index 0190d1c..3952bff 100644
--- a/drivers/dma/at_xdmac.c
+++ b/drivers/dma/at_xdmac.c
@@ -875,14 +875,14 @@ at_xdmac_interleaved_queue_desc(struct dma_chan *chan,
 
        if (xt->src_inc) {
                if (xt->src_sgl)
-                       chan_cc |=  AT_XDMAC_CC_SAM_UBS_DS_AM;
+                       chan_cc |=  AT_XDMAC_CC_SAM_UBS_AM;
                else
                        chan_cc |=  AT_XDMAC_CC_SAM_INCREMENTED_AM;
        }
 
        if (xt->dst_inc) {
                if (xt->dst_sgl)
-                       chan_cc |=  AT_XDMAC_CC_DAM_UBS_DS_AM;
+                       chan_cc |=  AT_XDMAC_CC_DAM_UBS_AM;
                else
                        chan_cc |=  AT_XDMAC_CC_DAM_INCREMENTED_AM;
        }
-- 
2.5.0

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