[PATCH] ARM: edma: Fix configuration parsing for SoCs with multiple eDMA3 CC

Peter Ujfalusi peter.ujfalusi at ti.com
Mon Aug 11 00:58:50 PDT 2014

On 08/05/2014 07:32 PM, Vinod Koul wrote:
> On Mon, Aug 04, 2014 at 03:26:56PM +0300, Peter Ujfalusi wrote:
>> The edma_setup_from_hw() should know about the CC number when parsing the
>> CCCFG register - when it reads the register to be precise. The base
>> addresses for CCs stored in an array and we need to provide the correct id
>> to edma_read() in order to read the correct register.
> Just an othognal question:
> I still see lot of code for edma in arm/. What is the plan to re/move that
> to dma/

Yes, there's still a big split. The code under arch/arm/common/ provides still
the 'legacy' edma API. This is still used by audio
sound/soc/davinci/davinci-pcm for older daVinci devices (AM335x. AM43xx uses
the edma-pcm).

And it is not that simple to deprecate davinci-pcm: it can use so called
ping-pong mode for audio data transfer. This mode is not possible via
dmaengine AFAIK.
I'm going to check if edma-pcm would work fine instead of the ping-pong mode.
If it does I can remove davinci-pcm and we can start cleaning up the edma code.


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