Re: [PATCH 4/9] dt-bindings: arm: qcom,coresight-static-replicator: add optional clocks

[Dmitry Baryshkov]

On Tue, Mar 18, 2025 at 01:37:23PM +0000, Suzuki K Poulose wrote:
> On 18/03/2025 12:19, Dmitry Baryshkov wrote:
> > On Tue, Mar 18, 2025 at 10:38:17AM +0000, Suzuki K Poulose wrote:
> > > On 17/03/2025 17:44, Dmitry Baryshkov wrote:
> > > 
> > > nit: Subject:
> > > 
> > > s/qcom,coresight-static-replicator/arm,coresight-static-replicator
> > > 
> > > > As most other CoreSight devices the replicator can use either of the
> > > > optional clocks (or both). Document those optional clocks in the schema.
> > > > 
> > > > Fixes: 3c15fddf3121 ("dt-bindings: arm: Convert CoreSight bindings to DT schema")
> > > > Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxxxxxxxx>
> > > > ---
> > > >    .../bindings/arm/arm,coresight-static-replicator.yaml          | 10 ++++++++++
> > > >    1 file changed, 10 insertions(+)
> > > > 
> > > > diff --git a/Documentation/devicetree/bindings/arm/arm,coresight-static-replicator.yaml b/Documentation/devicetree/bindings/arm/arm,coresight-static-replicator.yaml
> > > > index a6f793ea03b6c193fc0ff72a45e0249a63a2ba3c..56e64067ed3d63c5e293a0840858f13428bacb45 100644
> > > > --- a/Documentation/devicetree/bindings/arm/arm,coresight-static-replicator.yaml
> > > > +++ b/Documentation/devicetree/bindings/arm/arm,coresight-static-replicator.yaml
> > > > @@ -30,6 +30,16 @@ properties:
> > > >      power-domains:
> > > >        maxItems: 1
> > > > +  clocks:
> > > > +    minItems: 1
> > > > +    maxItems: 2
> > > > +
> > > 
> > > For the static replicator, you don't have an APB clock, as they can't be
> > > programmed. It may have an ATB clock. So minItems 0, maxItems: 1
> > 
> > It can, see qcom-apq8064.dtsi
> > 
> > Also minItems:0 doesn't make sense to me. I'd rather keep this as an
> > optional property rather than requiring an empty set.
> 
> Interesting, that must be atclk in fact. Because a static replicator
> only manages ATB transactions. It doesn't have an APB interface.

Ack. Unfortunately there are platforms (and grepping revealed more than
just APQ8064) that list the apb_pclk. We have to support those DTs :-(

> 
> I am not an expert in DTB schema. But the point is the clocks are optional.

This is handled by not listing the 'clocks' / 'clock-names' under the
'required' list.

> 
> Suzuki
> 
> 
> > 
> > > 
> > > Suzuki
> > > 
> > > 
> > > 
> > > > +  clock-names:
> > > > +    minItems: 1
> > > > +    enum:
> > > > +      - apb_pclk
> > > > +      - atclk
> > > > +
> > > >      in-ports:
> > > >        $ref: /schemas/graph.yaml#/properties/ports
> > > >        additionalProperties: false
> > > > 
> > > 
> > 
> 

-- 
With best wishes
Dmitry