RE: [Patch v4 01/11] dt-bindings: media: s5p-mfc: Add mfcv12 variant

["Aakarsh Jain" <aakarsh.jain@xxxxxxxxxxx>]

Hello Krzysztof

> -----Original Message-----
> From: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx>
> Sent: 25 October 2023 18:30
> To: Aakarsh Jain <aakarsh.jain@xxxxxxxxxxx>; linux-arm-
> kernel@xxxxxxxxxxxxxxxxxxx; linux-media@xxxxxxxxxxxxxxx; linux-
> kernel@xxxxxxxxxxxxxxx; devicetree@xxxxxxxxxxxxxxx
> Cc: m.szyprowski@xxxxxxxxxxx; andrzej.hajda@xxxxxxxxx;
> mchehab@xxxxxxxxxx; hverkuil-cisco@xxxxxxxxx;
> krzysztof.kozlowski+dt@xxxxxxxxxx; dillon.minfei@xxxxxxxxx;
> david.plowman@xxxxxxxxxxxxxxx; mark.rutland@xxxxxxx;
> robh+dt@xxxxxxxxxx; conor+dt@xxxxxxxxxx; linux-samsung-
> soc@xxxxxxxxxxxxxxx; andi@xxxxxxxxxxx; gost.dev@xxxxxxxxxxx;
> alim.akhtar@xxxxxxxxxxx; aswani.reddy@xxxxxxxxxxx;
> pankaj.dubey@xxxxxxxxxxx; ajaykumar.rs@xxxxxxxxxxx; linux-
> fsd@xxxxxxxxx
> Subject: Re: [Patch v4 01/11] dt-bindings: media: s5p-mfc: Add mfcv12
> variant
> 
> On 25/10/2023 12:22, Aakarsh Jain wrote:
> > Add Tesla FSD MFC(MFC v12) compatible.
> >
> > Cc: linux-fsd@xxxxxxxxx
> > Signed-off-by: Aakarsh Jain <aakarsh.jain@xxxxxxxxxxx>
> > ---
> 
> No changelog and your cover letter does not explain what happened here.
> Specifically, why did you decide to ignore received tag.
> 
Last patch series we had two different patches for schema which was one for adding MFCv12 compatible string and other for adding its HW properties.
In one of the patches you gave reviewed-by tag. Since mfc dt_schema got merged already, and this is relatively  new patch so thought of getting reviewed again.

Link to those patches:
https://patchwork.kernel.org/project/linux-media/patch/20221011122516.32135-2-aakarsh.jain@xxxxxxxxxxx/
https://patchwork.kernel.org/project/linux-media/patch/20221011122516.32135-3-aakarsh.jain@xxxxxxxxxxx/    

if you are ok, I will add your reviewed-by in next patch series.

> >  .../bindings/media/samsung,s5p-mfc.yaml          | 16 ++++++++++++++++
> >  1 file changed, 16 insertions(+)
> >
> > diff --git a/Documentation/devicetree/bindings/media/samsung,s5p-
> mfc.yaml b/Documentation/devicetree/bindings/media/samsung,s5p-
> mfc.yaml
> > index 084b44582a43..c30eb309f670 100644
> > --- a/Documentation/devicetree/bindings/media/samsung,s5p-mfc.yaml
> > +++ b/Documentation/devicetree/bindings/media/samsung,s5p-mfc.yaml
> > @@ -24,6 +24,7 @@ properties:
> >            - samsung,mfc-v7                # Exynos5420
> >            - samsung,mfc-v8                # Exynos5800
> >            - samsung,mfc-v10               # Exynos7880
> > +          - tesla,fsd-mfc                 # Tesla FSD
> >        - items:
> >            - enum:
> >                - samsung,exynos3250-mfc    # Exynos3250
> > @@ -165,6 +166,21 @@ allOf:
> >            minItems: 1
> >            maxItems: 2
> >
> > +  - if:
> > +      properties:
> > +        compatible:
> > +          contains:
> > +            enum:
> > +              - tesla,fsd-mfc
> > +    then:
> > +      properties:
> > +        clocks:
> > +          maxItems: 1
> > +        clock-names:
> > +          items:
> > +            - const: mfc
> > +        iommus: false
> 
> That's odd. How so? MFC v12 does not support IOMMU?
> 
MFC v12 do support IOMMU. But currently it is not enabled in SW (has dependencies on some of the floating dma-mapping patches) and not tested on upstream kernel. Current patch sets intend to add support for MFCv12 using reserve memory and later patches related to enable iommu will be posted (after resolving the dependencies). So I marked iommu property as false. 
Now what is your suggestion here? Should I keep iommu as false or add memory-region as below?
Ex-
  - if:
      properties:
        compatible:
          contains:
            enum:
              - tesla,fsd-mfc
    then:
      properties:
        clocks:
          maxItems: 1
        clock-names:
          items:
            - const: mfc
        memory-region:
          maxItems: 1


> Best regards,
> Krzysztof

Thanks for review.