[PATCH v3 5/7] mtd: onenand: omap2: Unify OMAP2 and OMAP3 DMA implementation

Tony Lindgren tony at atomide.com
Fri Nov 10 10:29:38 PST 2017


* Ladislav Michl <ladis at linux-mips.org> [171110 18:21]:
> On Fri, Nov 10, 2017 at 07:26:10AM -0800, Tony Lindgren wrote:
> > * Ladislav Michl <ladis at linux-mips.org> [171110 09:53]:
> > > On Fri, Nov 10, 2017 at 10:21:51AM +0200, Roger Quadros wrote:
> > > > On 09/11/17 11:15, Ladislav Michl wrote:
> > > > > Since the very first commit (36cd4fb5d277: "[MTD] [OneNAND] Add OMAP2 / OMAP3
> > > > > OneNAND driver") DMA is disabled for OMAP2. Later fixes thus went only into
> > > > > OMAP3 specific DMA functions which turned out not to be so OMAP3 specific.
> > > > > Therefore replace open coded timeout waiting for completion in OMAP3
> > > > > functions with API call and merge those two implementations.
> > > > > 
> > > > > Note that currently the is no single DMA user, so this change is basically
> > > > > no-op. Those interested will have to find DMA configuration in the
> > > > > linux-omap.git history.
> > > > > 
> > > > > Signed-off-by: Ladislav Michl <ladis at linux-mips.org>
> > > > 
> > > > I'll be happy if there are no OMAP2 vs OMAP3 differences in code but we need to
> > > > be absolutely sure that we don't break DMA functionality if it ever worked.
> > > 
> > > It probably worked at least for OMAP3 as it was enabled in legacy kernels.
> > > 
> > > > Can we somehow test OneNAND DMA on OMAP2 and OMAP3?
> > > > Tony?
> > > 
> > > I'll prepare next version patch serie for easier testing. Of course I would
> > > prefer to be able to test changes myself, but I do not have any Nokias :-)
> > 
> > I tested Peter's dma changes yesterday and they worked. Yeah if you want
> > me to test something a complete series or a git branch makes it easier
> > for me to follow what all is needed.
> 
> How did you configure DMA? Is there any additional patch?
> So far I prepared complete patchset including Peter's changes, but I might
> be good idea to start with something what's working for you.

I just made sure things keep working with Peter's changes, no additional
patches. So the dma is barely used at all.

Regards,

Tony



More information about the linux-mtd mailing list