Patch "dmaengine: at_xdmac: change block increment addressing mode" has been added to the 4.2-stable tree

This is a note to let you know that I've just added the patch titled

dmaengine: at_xdmac: change block increment addressing mode

to the 4.2-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
dmaengine-at_xdmac-change-block-increment-addressing-mode.patch
and it can be found in the queue-4.2 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Maxime Ripard <[email protected]>
Date: Tue, 15 Sep 2015 15:36:00 +0200
Subject: dmaengine: at_xdmac: change block increment addressing mode

From: Maxime Ripard <[email protected]>

commit a1cf09031e641d3cceaca4a4dd20ef6a785bc9b3 upstream.

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.

---
 drivers/dma/at_xdmac.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

@@ -878,14 +878,14 @@ at_xdmac_interleaved_queue_desc(struct d
 
 	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;
 	}

Patches currently in stable-queue which might be from [email protected] are

queue-4.2/dmaengine-at_xdmac-change-block-increment-addressing-mode.patch queue-4.2/watchdog-sunxi-fix-activation-of-system-reset.patch queue-4.2/arm-dts-sunxi-raise-minimum-cpu-voltage-for-sun7i-a20-to-meet-soc-specifications.patch