Re: [PATCH v5 3/5] dt-bindings: arm: Add qcom,qmi-id for remote etm

[Jinlong Mao]

On 2025/6/18 11:16, Bjorn Andersson wrote:
> On Thu, Apr 24, 2025 at 04:58:52AM -0700, Mao Jinlong wrote:
> > qcom,qmi-id is required for remote etm driver to find the remote
> > subsystem connection. It is the instance id used by qmi API to
> > communicate with remote processor.
> >
> > Signed-off-by: Mao Jinlong <quic_jinlmao@xxxxxxxxxxx>
> > ---
> >   .../bindings/arm/qcom,coresight-remote-etm.yaml        | 10 ++++++++++
> >   1 file changed, 10 insertions(+)
> >
> > diff --git a/Documentation/devicetree/bindings/arm/qcom,coresight-remote-etm.yaml b/Documentation/devicetree/bindings/arm/qcom,coresight-remote-etm.yaml
> > index 4fd5752978cd..947fe33738a3 100644
> > --- a/Documentation/devicetree/bindings/arm/qcom,coresight-remote-etm.yaml
> > +++ b/Documentation/devicetree/bindings/arm/qcom,coresight-remote-etm.yaml
> > @@ -20,6 +20,13 @@ properties:
> >     compatible:
> >       const: qcom,coresight-remote-etm
> >   
> > +  qcom,qmi-id:
>
> Why isn't this "qcom,qmi-instance-id" if that's what it represents?

ok.

> > +    $ref: /schemas/types.yaml#/definitions/uint32
> > +    description:
> > +      This id is used by qmi API to communicate with remote processor for
> > +      enabling and disabling remote etm. Each processor has its unique instance
> > +      id.
>
> DeviceTree describes the hardware and firmware interface, so don't
> describe properties in terms of what Linux will do with this value, but
> what it represents.

Sure. I will update it.

> > +
> >     out-ports:
> >       $ref: /schemas/graph.yaml#/properties/ports
> >       additionalProperties: false
> > @@ -32,6 +39,7 @@ properties:
> >   required:
> >     - compatible
> >     - out-ports
> > +  - qcom,qmi-id
>
> How can this suddenly be required, did devices described by this binding
> up until this point not work?

Without this instance id, remote etm won't work.

> If this is the case, make sure to clearly describe this in the commit
> message.
>
> Regards,
> Bjorn
>
> >   
> >   additionalProperties: false
> >   
> > @@ -40,6 +48,8 @@ examples:
> >       etm {
> >           compatible = "qcom,coresight-remote-etm";
> >   
> > +        qcom,qmi-id = <2>;
> > +
> >           out-ports {
> >               port {
> >                   modem_etm0_out_funnel_modem: endpoint {
> > --
> > 2.25.1