On Mon, Mar 17, 2014 at 09:14:14AM -0400, Jon Ringle wrote:
> On Mon, 17 Mar 2014, Sekhar Nori wrote:
> 
> > Hi Jon,
> > 
> > On Monday 17 March 2014 06:28 PM, Jon Ringle wrote:
> > > 
> > > On Mon, 17 Mar 2014, 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: <sta...@vger.kernel.org> # v3.12.x+
> > >> Cc: Joel Fernandes <jo...@ti.com>
> > >> Reported-by: Jon Ringle <jrin...@gridpoint.com>
> > >> Signed-off-by: Sekhar Nori <nsek...@ti.com>
> > >> ---
> > >> Jon, can you please confirm this fixes the issue you
> > >> reported?
> > > 
> > > The patch does not apply on linux-3.12 due to changes to the 3 context 
> > > lines at the start of the hunk.
> > > 
> > > But, I manually fixed up the code and it does fix the issue  on our 
> > > AM1808 
> > > board.
> > 
> > Thanks for the testing. The patch is meant for latest mainline but based
> > on what you said, a manual backport to v3.12-stable will be required.
> > 
> > Can you please reply with a formal Tested-by: ?
> 
> Tested-by: Jon Ringle <jrin...@gridpoint.com>
where is this patch, somehow am not able to find in my inbox or archives...

-- 
~Vinod
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