Re: [PATCH RESEND v4 0/6] dmaengine: dw: Fix src/dst addr width misconfig

Andy Shevchenko
2024-09-14T18:50:53Z

On Mon, Aug 05, 2024 at 03:25:35PM +0300, Serge Semin wrote:
> On Sat, Aug 03, 2024 at 09:29:54PM +0200, Andy Shevchenko wrote:
> > On Fri, Aug 2, 2024 at 9:51 AM Serge Semin <fancer.lancer@gmail.com> wrote:
> > >
> > > The main goal of this series is to fix the data disappearance in case of
> > > the DW UART handled by the DW AHB DMA engine. The problem happens on a
> > > portion of the data received when the pre-initialized DEV_TO_MEM
> > > DMA-transfer is paused and then disabled. The data just hangs up in the
> > > DMA-engine FIFO and isn't flushed out to the memory on the DMA-channel
> > > suspension (see the second commit log for details). On a way to find the
> > > denoted problem fix it was discovered that the driver doesn't verify the
> > > peripheral device address width specified by a client driver, which in its
> > > turn if unsupported or undefined value passed may cause DMA-transfer being
> > > misconfigured. It's fixed in the first patch of the series.
> > >
> > > In addition to that three cleanup patches follow the fixes described above
> > > in order to make the DWC-engine configuration procedure more coherent.
> > > First one simplifies the CTL_LO register setup methods. Second and third
> > > patches simplify the max-burst calculation procedure and unify it with the
> > > rest of the verification methods. Please see the patches log for more
> > > details.
> > >
> > > Final patch is another cleanup which unifies the status variables naming
> > > in the driver.
> >
> > Acked-by: Andy Shevchenko <andy@kernel.org>
>
> Awesome! Thanks.

Not really :-)
This series broke iDMA32 + SPI PXA2xx on Intel Merrifield. I haven't
had time to investigate further, but rolling back all patches helps.

+Cc: Ferry who might also test and maybe investigate as he reported the
issue to me initially.

--
With Best Regards,
Andy Shevchenko