Re: [PATCH] Fix DMA on Dreamcast

["Peter Bortas" <bortas@gmail.com>]

On 7/21/07, Adrian McMenamin <adrianmcmenamin@gmail.com> wrote:
> On 20/07/07, Andrew Morton <akpm@linux-foundation.org> wrote:
> > On Thu, 19 Jul 2007 20:30:34 +0100
> > "Adrian McMenamin" <adrianmcmenamin@gmail.com> wrote:
> >
> > > I think my first attempt to post this may have got lost in space somewhere.
> > >
> > > Signed-off by: Adrian McMenamin <adrian@mcmen.demon.co.uk>
> >
> > Please provide a description of what problem this change is solving, and how
> > it solves it.
> >
> Andrew
>
> Sorry, just noticed this. Without this patch the Dreamcast won't boot
> when configured with the correct DMA settings in Kbuild. You can
> either patch the kernel or use the wrong settings in the build.
>
> Essentially the SH DMA API code is broken in that it doesn't correctly
> match the DMA virtual channel to the DMAC.
>
> The patch seems to fix this, though further testing has reveled there
> may either be an issue with the patch or an issue with other drivers
> using DMA and which have worked because they inadvertently relied on
> the breakage in the DMA API code.

Sidenote: Does Linux handle the Dreamcast DMA errata?

-- 
Peter Bortas