[PATCH v4 2/3] dt-bindings: arm: Add Coresight Dummy Trace

Hao Zhang quic_hazha at quicinc.com
Tue May 9 20:21:59 PDT 2023


Hi Suzuki, Leo,

On 5/5/2023 8:05 PM, Leo Yan wrote:
> On Fri, May 05, 2023 at 11:54:03AM +0100, Suzuki Kuruppassery Poulose wrote:
> 
> [...]
> 
>>> +title: ARM Coresight Dummy component
>>> +
>>> +description: |
>>> +  Coresight Dummy Trace Module is for the specific devices that kernel
>>> +  don't have permission to access or configure, e.g., CoreSight TPDMs
>>> +  on Qualcomm platforms. So there need driver to register dummy devices
>>> +  as Coresight devices. It may also be used to define components that
>>> +  may not have any programming interfaces (e.g, static links), so that
>>> +  paths can be established in the driver. Provide Coresight API for
>>> +  dummy device operations, such as enabling and disabling dummy devices.
>>> +  Build the Coresight path for dummy sink or dummy source for debugging. > +
>>> +  The primary use case of the coresight dummy is to build path in kernel
>>> +  side for dummy sink and dummy source.
>>> +
>>> +maintainers:
>>> +  - Mao Jinlong <quic_jinlmao at quicinc.com>
>>> +  - Tao Zhang <quic_taozha at quicinc.com>
>>> +  - Hao Zhang <quic_hazha at quicinc.com>
>>> +  - Yuanfang Zhang <quic_yuanfang at quicinc.com>
>>
>> Given this is a generic "CoreSight" component, I would prefer to have the
>> CoreSight subsystem maintainers listed here (too). I don't mind
>> the entries above, but would like to make sure that the subsystem
>> people are aware of the changes happening here. Please use:
>>
>> Mike Leach <mike.leach at linaro.org>
>> Suzuki K Poulose <suzuki.poulose at arm.com>
>> Leo Yan <leo.yan at linaro.org>
>  > Given I am spending little time on CoreSight reviewing, I'd like to
> use James Clark's email address to replace my own; I believe this
> would benefit long term maintenance.
> 
>    James Clark <james.clark at arm.com>
> 
> Thanks!
>
Thanks for your review. I will update the maintainers in the next patch 
series.

Thanks,
Hao

>> With the above:
>>
>> Acked-by: Suzuki K Poulose <suzuki.poulose at arm.com>
>>
>>> +
>>> +properties:
>>> +  compatible:
>>> +    items:
>>> +      - enum:
>>> +          - arm,coresight-dummy-sink
>>> +          - arm,coresight-dummy-source
>>> +
>>> +  out-ports:
>>> +    $ref: /schemas/graph.yaml#/properties/ports
>>> +
>>> +    properties:
>>> +      port:
>>> +        description: Output connection from the source to Coresight
>>> +          Trace bus.
>>> +        $ref: /schemas/graph.yaml#/properties/port
>>> +
>>> +  in-ports:
>>> +    $ref: /schemas/graph.yaml#/properties/ports
>>> +
>>> +    properties:
>>> +      port:
>>> +        description: Input connection from the Coresight Trace bus to
>>> +          dummy sink, such as Embedded USB debugger(EUD).
>>> +        $ref: /schemas/graph.yaml#/properties/port
>>> +
>>> +required:
>>> +  - compatible
>>> +
>>> +if:
>>> +  # If the compatible contains the below value
>>> +  properties:
>>> +    compatible:
>>> +      contains:
>>> +        const: arm,coresight-dummy-sink
>>> +
>>> +then:
>>> +  required:
>>> +    - in-ports
>>> +
>>> +else:
>>> +  required:
>>> +    - out-ports
>>> +
>>> +additionalProperties: false
>>> +
>>> +examples:
>>> +  # Minimum dummy sink definition. Dummy sink connect to coresight replicator.
>>> +  - |
>>> +    sink {
>>> +      compatible = "arm,coresight-dummy-sink";
>>> +
>>> +      in-ports {
>>> +        port {
>>> +          eud_in_replicator_swao: endpoint {
>>> +            remote-endpoint = <&replicator_swao_out_eud>;
>>> +          };
>>> +        };
>>> +      };
>>> +    };
>>> +
>>> +  # Minimum dummy source definition. Dummy source connect to coresight funnel.
>>> +  - |
>>> +    source {
>>> +      compatible = "arm,coresight-dummy-source";
>>> +
>>> +      out-ports {
>>> +        port {
>>> +          dummy_riscv_out_funnel_swao: endpoint {
>>> +            remote-endpoint = <&funnel_swao_in_dummy_riscv>;
>>> +          };
>>> +        };
>>> +      };
>>> +    };
>>> +
>>> +...
>>



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