Re: [PATCH v4 09/11] dmaengine: dw: Initialize min_burst capability

[Andy Shevchenko]

On Fri, May 29, 2020 at 01:25:15PM +0300, Andy Shevchenko wrote:
> On Fri, May 29, 2020 at 01:23:59AM +0300, Serge Semin wrote:
> > According to the DW APB DMAC data book the minimum burst transaction
> > length is 1 and it's true for any version of the controller since
> > isn't parametrised in the coreAssembler so can't be changed at the
> > IP-core synthesis stage. Let's initialise the min_burst member of the
> > DMA controller descriptor so the DMA clients could use it to properly
> > optimize the DMA requests.

...

> >  	/* DMA capabilities */
> 
> > +	dw->dma.min_burst = 1;
> 
> Perhaps then relaxed maximum, like
> 
> 	dw->dma.max_burst = 256;
> 
> (channels will update this)
> 
> ?

And forgot to mention that perhaps we need a definitions for both.

> >  	dw->dma.src_addr_widths = DW_DMA_BUSWIDTHS;
> >  	dw->dma.dst_addr_widths = DW_DMA_BUSWIDTHS;

-- 
With Best Regards,
Andy Shevchenko