Re: [PATCH v2 2/4] dt-bindings: arm: Add binding document for Coresight Control Unit device.

[JieGan <quic_jiegan@quicinc.com>]

On Mon, Jul 08, 2024 at 10:41:55AM +0100, Suzuki K Poulose wrote:
> On 05/07/2024 10:00, Jie Gan wrote:
> > Add binding document for Coresight Control Unit device.
> 
> nit: This is again too generic ? corsight-tmc-control-unit ? After all
> thats what it is and not a *generic* coresight control unit ?
>
coresight-tmc-control-unit is much better. We will check it.
 
> > 
> > Signed-off-by: Jie Gan <quic_jiegan@quicinc.com>
> > ---
> >   .../bindings/arm/qcom,coresight-ccu.yaml      | 87 +++++++++++++++++++
> >   1 file changed, 87 insertions(+)
> >   create mode 100644 Documentation/devicetree/bindings/arm/qcom,coresight-ccu.yaml
> > 
> > diff --git a/Documentation/devicetree/bindings/arm/qcom,coresight-ccu.yaml b/Documentation/devicetree/bindings/arm/qcom,coresight-ccu.yaml
> > new file mode 100644
> > index 000000000000..9bb8ced393a7
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/arm/qcom,coresight-ccu.yaml
> > @@ -0,0 +1,87 @@
> > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> > +%YAML 1.2
> > +---
> > +$id: http://devicetree.org/schemas/arm/qcom,coresight-ccu.yaml#
> > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > +
> > +title: CoreSight Control Unit
> > +
> > +maintainers:
> > +  - Yuanfang Zhang <quic_yuanfang@quicinc.com>
> > +  - Mao Jinlong <quic_jinlmao@quicinc.com>
> > +  - Jie Gan <quic_jiegan@quicinc.com>
> > +
> > +description:
> > +  The Coresight Control unit controls various Coresight behaviors.
> > +  Used to enable/disable ETR’s data filter function based on trace ID.
> > +
> > +properties:
> > +  compatible:
> > +    const: qcom,coresight-ccu
> > +
> > +  reg:
> > +    maxItems: 1
> > +
> > +  clocks:
> > +    maxItems: 1
> > +
> > +  clock-names:
> > +    items:
> > +      - const: apb_pclk
> > +
> > +  reg-names:
> > +    items:
> > +      - const: ccu-base
> > +
> > +  in-ports:
> > +    $ref: /schemas/graph.yaml#/properties/ports
> > +
> > +    unevaluatedProperties:
> > +      patternProperties:
> > +        '^port(@[0-7])?$':
> > +          description: Input connections from CoreSight Trace bus
> > +          $ref: /schemas/graph.yaml#/properties/port
> > +
> > +          properties:
> > +            qcom,ccu-atid-offset:
> 
> Why do we need this atid offset ? Couldn't this be mapped to the "port"
> number ?
> 
> e.g, input-port 0 on CCU => Offset x
>      input-port 1 on CCU => (Offset x + Size of 1 region)
If the first ATID offset remains constant, it appears to be feasible.
We will consider the possibility of this solution.

>
> I believe I mentioned this in the previous posting too ?
Yes, you mentioned before. I moved it from TMC filed to CCU filed.

> 
> Suzuki
>