Re: [PATCH v6 1/3] dma: at_xdmac: creation of the atmel eXtended DMA Controller driver

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Fri, Oct 17, 2014 at 08:53:57AM +0200, Ludovic Desroches wrote:

> > 
> > > > For memcpy why should we need slave_config. The system memory source and
> > > > destination width could be assumed to relastic values and then burst sizes
> > > > maxed for performance. These values make more sense for periphral where we
> > > > have to match up with the periphral
> > > 
> > > I don't tell I need slave_config. We have already talked about this. I don't
> > > see the problem. It is only a comment, a reminder. The only information
> > > I may need, one day, is the direction because we have to set src and dst
> > > interfaces. At the moment, all our products are done in a way nand flash
> > > and DDR are on the same interface so we don't have to care about
> > > direction.
> > > Since we don't have the direction, two solutions:
> > > - remember this limitation for next products, that's why there is this reminder,
> > > - change our nand driver in order to see nand as a peripheral instead of
> > >   a memory. 
> > I think treating NAND as memory may not be a right model. It should be
> > treated as periphral with incrementing and decrementing address value. That
> > way you should be able to set the right properties for it.
> > 
> > The system memory copy is right model for memcpy.
> 
> Ok, I'll discuss of it with the atmel nand maintener. Even if there is
> something to improve here, I hope it is not considered as a blocking point
> to get the xdmac driver included into 3.19 because at the moment we have no
> DMA on the SAMA5D4 recently introduced.

That sounds good to me, no this is non blocker here

And yes keeping the comment here is fine to warn folks.

-- 
~Vinod

--
To unsubscribe from this list: send the line "unsubscribe dmaengine" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html




[Index of Archives]     [Linux Kernel]     [Linux ARM (vger)]     [Linux ARM MSM]     [Linux Omap]     [Linux Arm]     [Linux Tegra]     [Fedora ARM]     [Linux for Samsung SOC]     [eCos]     [Linux PCI]     [Linux Fastboot]     [Gcc Help]     [Git]     [DCCP]     [IETF Announce]     [Security]     [Linux MIPS]     [Yosemite Campsites]

  Powered by Linux