On Monday 14 April 2014 02:27 PM, Vinod Koul wrote: > On Mon, Apr 14, 2014 at 02:01:11PM +0530, Sekhar Nori wrote: >> Vinod, >> >> On Wednesday 19 March 2014 11:25 AM, Sekhar Nori wrote: >>> The code to handle any length SG lists calls edma_resume() >>> even before edma_start() is called. This is incorrect >>> because edma_resume() enables edma events on the channel >>> after which CPU (in edma_start) cannot clear posted >>> events by writing to ECR (per the EDMA user's guide). >>> >>> Because of this EDMA transfers fail to start if due >>> to some reason there is a pending EDMA event registered >>> even before EDMA transfers are started. This can happen if >>> an EDMA event is a byproduct of device initialization. >>> >>> Fix this by calling edma_resume() only if it is not the >>> first batch of MAX_NR_SG elements. >>> >>> Without this patch, MMC/SD fails to function on DA850 EVM >>> with DMA. The behaviour is triggered by specific IP and >>> this can explain why the issue was not reported before >>> (example with MMC/SD on AM335x). >>> >>> Tested on DA850 EVM and AM335x EVM-SK using MMC/SD card. >>> >>> Cc: stable@xxxxxxxxxxxxxxx # v3.12.x+ >>> Cc: Joel Fernandes <joelf@xxxxxx> >>> Acked-by: Joel Fernandes <joelf@xxxxxx> >>> Tested-by: Jon Ringle <jringle@xxxxxxxxxxxxx> >>> Tested-by: Alexander Holler <holler@xxxxxxxxxxxxx> >>> Reported-by: Jon Ringle <jringle@xxxxxxxxxxxxx> >>> Signed-off-by: Sekhar Nori <nsekhar@xxxxxx> >> >> Looks like this patch is not in mainline still? > > Sorry looks like I have missed sending the email. I had applied it last week and > today rebased after rc1. It would be part of rc2... Thank you! Regards, Sekhar -- To unsubscribe from this list: send the line "unsubscribe dmaengine" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
