RE: [PATCH v5 16/16] dmaengine: dw-axi-dmac: Virtually split the linked-list

[Sia, Jee Heng]

> -----Original Message-----
> From: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
> Sent: 23 November 2020 6:23 PM
> To: Sia, Jee Heng <jee.heng.sia@xxxxxxxxx>
> Cc: vkoul@xxxxxxxxxx; Eugeniy.Paltsev@xxxxxxxxxxxx;
> robh+dt@xxxxxxxxxx; dmaengine@xxxxxxxxxxxxxxx; linux-
> kernel@xxxxxxxxxxxxxxx; devicetree@xxxxxxxxxxxxxxx
> Subject: Re: [PATCH v5 16/16] dmaengine: dw-axi-dmac: Virtually split
> the linked-list
> 
> On Mon, Nov 23, 2020 at 10:34:52AM +0800, Sia Jee Heng wrote:
> > AxiDMA driver exposed the dma_set_max_seg_size() to the
> DMAENGINE.
> > It shall helps the DMA clients to create size-optimized linked-list
> > for the controller.
> >
> > However, there are certain situations where DMA client might not be
> > abled to benefit from the dma_get_max_seg_size() if the segment
> size
> > can't meet the nature of the DMA client's operation.
> >
> > In the case of ALSA operation, ALSA application and driver expecting
> > to run in a period of larger than 10ms regardless of the bit depth.
> > With this large period, there is a strong request to split the
> > linked-list in the AxiDMA driver.
> 
> I'm wondering why ASoC generic code can't use DMA channel and
> device capabilities and prepare SG list with all limitations taken into
> account.
[>>] There is no further comment to split the linked-list in DMA, I assume we can proceed with this patch.
[>>] The RFC patch is submitted at below link and you are in the thread.
[>>] https://lore.kernel.org/alsa-devel/CO1PR11MB5026545F07968DBC5386CF45DACD0@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx/T/#u

> 
> 
> --
> With Best Regards,
> Andy Shevchenko
>