Re: [PATCH v5 1/3] ARM: add CPPI 4.1 DMA support

[Sergei Shtylyov <sshtylyov@mvista.com>]

Hello.

On 03-01-2011 20:01, Gupta, Ajay Kumar wrote:

>>>> Add support for Texas Instuments Communication Port Programming Interface 4.1
>>>> (CPPI 4.1) used on OMAP-L1x/DA8xx and AM35x.

>>>> At this moment, only the DMA controller and queue manager are supported.
>>>> Support for the buffer manager is lacking but these chips don't have it anyway.

>>>> Signed-off-by: Sergei Shtylyov<sshtylyov@ru.mvista.com>
>>>> Signed-off-by: Sekhar Nori<nsekhar@ti.com>

>>>     Russell, you have recently discarded this patch from your patch
>>> system. Can we know the reason?

>> It was recently discussed with TI, and various people raised concerns
>> about it.  I don't remember the exact details, and I wish they'd raise
>> them with the patch author directly.  It may have been that it's
>> inventing its own API rather than using something like the DMA engine
>> API.

>> Adding linux-omap to try to get a response there.

> Sergei,
> This issue was discussed recently at TI and proposal was to place it to
> drivers/dma folder.

    Note that I have neither time nor inclination to do this work (not do I 
think it's even feasible), so it will have to fall on TI's shoulders...

> Moreover, even Felipe also seems to move other musb
> DMAs (Inventra, CPPI3.0, TUSB) to drivers/dma.

    Frankly speaking, I doubt that drivers/dma/ will have place for the purely 
MUSB specific DMA engines such as the named ones (there's no TUSB DMA BTW -- 
it uses OMAP DMA).

> Regards,
> Ajay

WBR, Sergei