Re: [PATCH] Add 'dma-noncoherent' property as a standard property

["Heiko Stübner" <heiko-4mtYJXux2i+zQB+pC5nmwQ@public.gmane.org>]

Hi Rob,

Am Montag, 27. Juni 2022, 17:51:51 CEST schrieb Heiko Stübner:
> Am Montag, 27. Juni 2022, 17:14:45 CEST schrieb Rob Herring:
> > On Sun, Jun 19, 2022 at 2:37 PM Heiko Stuebner <heiko-4mtYJXux2i+zQB+pC5nmwQ@public.gmane.org> wrote:
> > >
> > > Similar to the 'dma-coherent' property, some architectures may be coherent
> > > by default with some devices being non-coherent. Add a property for this
> > > case tool.
> > 
> > Looks fine, but I also need a schema.
> > 
> > Yeah, that's redundant unfortunately. Maybe someday someone will care
> > enough to generate the spec from the schemas.
> 
> No worries and sorry I didn't think of where the schema comes from
> in the first place. I'll do the relevant schema work as well.

Done in https://github.com/devicetree-org/dt-schema/pull/78 .

I wasn't sure about the "development model" of dt-schema [0] but there
were already github pull-requests pending, so I've added another one
for the new property :-) .

Heiko


[0] The devicetree-specification documentation said mailinglist, though
I also see pull-requests there now that I was looking at github.

> > > Signed-off-by: Heiko Stuebner <heiko-4mtYJXux2i+zQB+pC5nmwQ@public.gmane.org>
> > > ---
> > > Companion patch to RISC-V Zicbom noncoherent dma support
> > > https://lore.kernel.org/linux-riscv/20220619203212.3604485-1-heiko-4mtYJXux2i+zQB+pC5nmwQ@public.gmane.org/
> > >
> > >  source/chapter2-devicetree-basics.rst | 13 +++++++++++++
> > >  1 file changed, 13 insertions(+)
> > >
> > > diff --git a/source/chapter2-devicetree-basics.rst b/source/chapter2-devicetree-basics.rst
> > > index 47d2fad..bdd7b9f 100644
> > > --- a/source/chapter2-devicetree-basics.rst
> > > +++ b/source/chapter2-devicetree-basics.rst
> > > @@ -832,6 +832,19 @@ Description:
> > >     coherent DMA operations. Some architectures have coherent DMA by default
> > >     and this property is not applicable.
> > >
> > > +dma-noncoherent
> > > +~~~~~~~~~~~~
> > > +
> > > +Property name: ``dma-noncoherent``
> > > +
> > > +Value type: ``<empty>``
> > > +
> > > +Description:
> > > +   For architectures which are by default coherent for I/O, the
> > > +   *dma-noncoherent* property is used to indicate a device is not capable of
> > > +   coherent DMA operations. Some architectures have non-coherent DMA by
> > > +   default and this property is not applicable.
> > > +
> > >  name (deprecated)
> > >  ~~~~~~~~~~~~~~~~~
> > >
> > > --
> > > 2.35.1
> > >
> > 
> 
>