[alsa-devel] [PATCH 4/4] ASoC: DaVinci: pcm, fix underrun by using sram

[Troy Kisky]

Nori, Sekhar wrote:
> On Wed, Jul 14, 2010 at 00:31:00, troy.kisky at boundarydevices.com wrote:
>> On Tue 13/07/10 6:00 AM , "Nori, Sekhar" nsekhar at ti.com sent:
>>
>
>>       The reason is so that the IRAM data can be fetched and used
>> while
>>
>>       EVENTQ_1 fetches the next buffer of data from sdram into IRAM.
> 
> Thanks for the explanation. That sounds reasonable.
> 
> Just curious as to whether you actually faced an issue
> when using the same event queue for both transfers?
> 
> I just tested this on DM365 with both transfers on EDMAQ_0
> with 16K each of capture and playback IRAM at 48KHz
> sampling rate and did not find any issue.
> 
> Anyway it makes sense to make provision for platform to choose
> different queues for both transfers so will implement my patch
> that way.
> 
> Thanks,
> Sekhar
> 

IIRC, the DM365 has a fifo, the 6443/6446 doesn't. So, the 365 doesn't
need to use IRAM and shouldn't use it. Test using the same controller
on a board without a fifo.

Troy