Re: [PATCH 04/25] dmaengine: Fix dma_slave_config.dst_addr description

Manivannan Sadhasivam
2022-03-31T10:50:45Z

On Thu, Mar 31, 2022 at 10:13:43AM +0300, Serge Semin wrote:
> On Thu, Mar 31, 2022 at 11:08:06AM +0530, Vinod Koul wrote:
> > On 24-03-22, 19:38, Manivannan Sadhasivam wrote:
> > > On Thu, Mar 24, 2022 at 04:48:15AM +0300, Serge Semin wrote:
> > > > Most likely due to a copy-paste mistake the dst_addr member of the
> > > > dma_slave_config structure has been marked as ignored if the !source!
> > > > address belong to the memory. That is relevant to the src_addr field of
> > > > the structure while the dst_addr field as containing a destination device
> > > > address is supposed to be ignored if the destination is the CPU memory.
> > > > Let's fix the field description accordingly.
> > > >
> > > > Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
> > >
> > > Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
> > >
> > > One suggestion below.
> > >
> > > > ---
> > > > include/linux/dmaengine.h | 2 +-
> > > > 1 file changed, 1 insertion(+), 1 deletion(-)
> > > >
> > > > diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h
> > > > index 842d4f7ca752..f204ea16ac1c 100644
> > > > --- a/include/linux/dmaengine.h
> > > > +++ b/include/linux/dmaengine.h
> > > > @@ -395,7 +395,7 @@ enum dma_slave_buswidth {
> > > > * should be read (RX), if the source is memory this argument is
> > > > * ignored.
> > > > * @dst_addr: this is the physical address where DMA slave data
> > > > - * should be written (TX), if the source is memory this argument
> > > > + * should be written (TX), if the destination is memory this argument
> > >
>
> > > Should we rename "memory" to "local memory" or something similar?
> >
> > what do you mean by local memory :)
>
> Most likely Manivannan just confused the whole eDMA device specifics
> with this patch purpose. This commit has nothing to do with "local"
> and "remote" device memory. Such definitions are relevant to the DW
> eDMA setups (whether device is integrated into the PCIe Host/End-point
> controller then the CPU memory is a local memory for it, or it's a
> remote PCI End-point, then the CPU memory is a remote memory for it).
>

Ah, yes indeed. While I was reviewing the eDMA patches I just went with that
context. Sorry for the noise.

Thanks,
Mani

> Guys. Regarding the patchsets review procedure. I notice all the
> comments. Just didn't have time to respond so far. Will do that till
> the end of the week.
>
> -Sergey
>
> >
> > --
> > ~Vinod