From mboxrd@z Thu Jan 1 00:00:00 1970 From: peter.ujfalusi@ti.com (Peter Ujfalusi) Date: Fri, 16 Sep 2016 13:53:15 +0300 Subject: [PATCH] dmaengine: omap-dma: Enable burst and data pack for SG Message-ID: <20160916105315.28320-1-peter.ujfalusi@ti.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org From: Misael Lopez Cruz Enable the burst and data pack modes for the scatter-gather in order to improve the throughput of the data transfers. The improvement has been verified with MMC HS200 mode in the DRA72 EVM using the iozone tool to compare the read throughput (in kB/s) with and without burst/pack for different reclens (in kB). With reclen Baseline sDMA burst/pack ------ -------- --------------- 64 46568 50820 128 57564 63413 256 65634 74937 512 72427 83483 1024 74563 84504 2048 76265 86079 4096 78045 87335 8192 78989 88154 16384 81265 91034 Signed-off-by: Misael Lopez Cruz Signed-off-by: Peter Ujfalusi --- drivers/dma/omap-dma.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/drivers/dma/omap-dma.c b/drivers/dma/omap-dma.c index 1b7f5f32bf74..7ca27d4b1c54 100644 --- a/drivers/dma/omap-dma.c +++ b/drivers/dma/omap-dma.c @@ -904,13 +904,16 @@ static struct dma_async_tx_descriptor *omap_dma_prep_slave_sg( d->es = es; d->ccr = c->ccr | CCR_SYNC_FRAME; - if (dir == DMA_DEV_TO_MEM) + if (dir == DMA_DEV_TO_MEM) { d->ccr |= CCR_DST_AMODE_POSTINC | CCR_SRC_AMODE_CONSTANT; - else + d->csdp = CSDP_DST_BURST_64 | CSDP_DST_PACKED; + } else { d->ccr |= CCR_DST_AMODE_CONSTANT | CCR_SRC_AMODE_POSTINC; + d->csdp = CSDP_SRC_BURST_64 | CSDP_SRC_PACKED; + } d->cicr = CICR_DROP_IE | CICR_BLOCK_IE; - d->csdp = es; + d->csdp |= es; if (dma_omap1()) { d->cicr |= CICR_TOUT_IE; -- 2.10.0