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dmaengine: at_xdmac: change block increment addressing mode

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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 <maxime.ripard@free-electrons.com>
Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Fixes: 6007ccb577 ("dmaengine: xdmac: Add interleaved transfer support")
Cc: stable@vger.kernel.org #4.2
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
This commit is contained in:
Maxime Ripard 2015-09-15 15:36:00 +02:00 • committed by Vinod Koul
parent 6bea0f6d1c
commit a1cf09031e
1 changed files with 2 additions and 2 deletions

4
drivers/dma/at_xdmac.c
View file

@ -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;
}