Re: [PATCH v2 1/9] dt-bindings: arm: Add support for DSB element

[Tao Zhang]

Hi Suzuki,

在 2/22/2023 2:11 AM, Suzuki K Poulose 写道:
> On 19/01/2023 07:41, Tao Zhang wrote:
> > Add property "qcom,dsb-elem-size" to support DSB(Discrete Single
> > Bit) element for TPDA. Specifies the DSB element size supported
> > by each monitor connected to the aggregator on each port. Should
> > be specified in pairs (port, dsb element size).
> >
> > Signed-off-by: Tao Zhang <quic_taozha@xxxxxxxxxxx>
> > Signed-off-by: Tao Zhang <taozha@xxxxxxxxxxxxxxxx>
> > ---
> >   .../bindings/arm/qcom,coresight-tpda.yaml          | 22 
> > ++++++++++++++++++++++
> >   1 file changed, 22 insertions(+)
> >
> > diff --git 
> > a/Documentation/devicetree/bindings/arm/qcom,coresight-tpda.yaml 
> > b/Documentation/devicetree/bindings/arm/qcom,coresight-tpda.yaml
> > index 2ec9b5b..298db7f 100644
> > --- a/Documentation/devicetree/bindings/arm/qcom,coresight-tpda.yaml
> > +++ b/Documentation/devicetree/bindings/arm/qcom,coresight-tpda.yaml
> > @@ -58,6 +58,26 @@ properties:
> >       minItems: 1
> >       maxItems: 2
> >   +  qcom,dsb-element-size:
> > +    description: |
> > +      Specifies the DSB(Discrete Single Bit) element size supported by
> > +      each monitor connected to the aggregator on each port. Should be
> > +      specified in pairs <port, dsb element size>.
>
> Isn't this a property of the TPDM connected to the port ? i.e. the DSB 
> size ? Thus shouldn't this be part of the TPDM device (and the TPDA 
> will be able to find it from the TPDM device) ?
Since  the port number is about the input port of TPDA, this property 
needs to be configured in the TPDA-related settings.

In our current design, TPDM doesn't have a register to record the DSB 
size, and TPDA cannot actively know the TPDM DSB size from the TPDM device.

> Suzuki

Best,

Tao