diff mbox

dmaengine: omap-dma: Allow DMA controller to prefetch data

Message ID 20121119163727.GB9758@animalcreek.com (mailing list archive)
State New, archived
Headers show

Commit Message

Mark Greer Nov. 19, 2012, 4:37 p.m. UTC 
From: "Mark A. Greer" <mgreer@animalcreek.com>

Enable DMA prefetching for non-cyclic DMAs by setting the
'OMAP_DMA_DST_SYNC_PREFETCH' flag when there is a destination
synchronized DMA transfer.  Prefetching is not allowed on
source synchronized DMA transfers.  It is not allowed on
cyclic DMAs either since that can cause issues with some
users (e.g., suspending/resuming audio).

CC: Russell King <rmk+kernel@arm.linux.org.uk>
CC: Péter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Mark A. Greer <mgreer@animalcreek.com>
---
 drivers/dma/omap-dma.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Mark Greer Jan. 15, 2013, 6:52 p.m. UTC | #1 
On Mon, Nov 19, 2012 at 09:37:27AM -0700, Mark A. Greer wrote:
> From: "Mark A. Greer" <mgreer@animalcreek.com>
> 
> Enable DMA prefetching for non-cyclic DMAs by setting the
> 'OMAP_DMA_DST_SYNC_PREFETCH' flag when there is a destination
> synchronized DMA transfer.  Prefetching is not allowed on
> source synchronized DMA transfers.  It is not allowed on
> cyclic DMAs either since that can cause issues with some
> users (e.g., suspending/resuming audio).
> 
> CC: Russell King <rmk+kernel@arm.linux.org.uk>
> CC: Péter Ujfalusi <peter.ujfalusi@ti.com>
> Signed-off-by: Mark A. Greer <mgreer@animalcreek.com>
> ---
>  drivers/dma/omap-dma.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/dma/omap-dma.c b/drivers/dma/omap-dma.c
> index bb2d8e7..3932eab 100644
> --- a/drivers/dma/omap-dma.c
> +++ b/drivers/dma/omap-dma.c
> @@ -310,7 +310,7 @@ static struct dma_async_tx_descriptor *omap_dma_prep_slave_sg(
>  		dev_addr = c->cfg.dst_addr;
>  		dev_width = c->cfg.dst_addr_width;
>  		burst = c->cfg.dst_maxburst;
> -		sync_type = OMAP_DMA_DST_SYNC;
> +		sync_type = OMAP_DMA_DST_SYNC_PREFETCH;
>  	} else {
>  		dev_err(chan->device->dev, "%s: bad direction?\n", __func__);
>  		return NULL;
> -- 
> 1.7.12

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diff mbox

Patch

diff --git a/drivers/dma/omap-dma.c b/drivers/dma/omap-dma.c
index bb2d8e7..3932eab 100644
--- a/drivers/dma/omap-dma.c
+++ b/drivers/dma/omap-dma.c
@@ -310,7 +310,7 @@  static struct dma_async_tx_descriptor *omap_dma_prep_slave_sg(
 		dev_addr = c->cfg.dst_addr;
 		dev_width = c->cfg.dst_addr_width;
 		burst = c->cfg.dst_maxburst;
-		sync_type = OMAP_DMA_DST_SYNC;
+		sync_type = OMAP_DMA_DST_SYNC_PREFETCH;
 	} else {
 		dev_err(chan->device->dev, "%s: bad direction?\n", __func__);
 		return NULL;