[PATCH v6 6/9] dt-bindings: arm: add an interrupt property for Coresight CTCU

[Jie Gan]

On 12/4/2025 5:22 PM, Suzuki K Poulose wrote:
> On 04/12/2025 02:53, Jie Gan wrote:
>>
>>
>> On 12/4/2025 2:14 AM, Suzuki K Poulose wrote:
>>> On 08/09/2025 03:01, Jie Gan wrote:
>>>> Add an interrupt property to CTCU device. The interrupt will be 
>>>> triggered
>>>> when the data size in the ETR buffer exceeds the threshold of the
>>>> BYTECNTRVAL register. Programming a threshold in the BYTECNTRVAL 
>>>> register
>>>> of CTCU device will enable the interrupt.
>>>>
>>>> Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski at linaro.org>
>>>> Signed-off-by: Jie Gan <jie.gan at oss.qualcomm.com>
>>>> ---
>>>>   .../devicetree/bindings/arm/qcom,coresight-ctcu.yaml    | 17 +++++ 
>>>> + + ++++++++++
>>>>   1 file changed, 17 insertions(+)
>>>>
>>>> diff --git a/Documentation/devicetree/bindings/arm/qcom,coresight- 
>>>> ctcu.yaml b/Documentation/devicetree/bindings/arm/qcom,coresight- 
>>>> ctcu.yaml
>>>> index 843b52eaf872..ea05ad8f3dd3 100644
>>>> --- a/Documentation/devicetree/bindings/arm/qcom,coresight-ctcu.yaml
>>>> +++ b/Documentation/devicetree/bindings/arm/qcom,coresight-ctcu.yaml
>>>> @@ -39,6 +39,16 @@ properties:
>>>>       items:
>>>>         - const: apb
>>>> +  interrupts:
>>>> +    items:
>>>> +      - description: Byte cntr interrupt for etr0
>>>> +      - description: Byte cntr interrupt for etr1
>>>> +
>>>> +  interrupt-names:
>>>> +    items:
>>>> +      - const: etr0
>>>> +      - const: etr1
>>>
>>
>> Hi Suzuki,
>>
>>> Why are they named "etr0" "etr1" ? That would be confusing, isn't it, 
>>> especially with the Linux driver naming things randomly for the TMC- 
>>> ETRs.
>>>
>>
>> Yes, it will cause misunderstandings since the "etr0" here may not the 
>> right device we are expecting.
>>
>>>
>>> What we want is the "port" number corresponding to the "TMC-ETR" being
>>> monitored ?
>>>
>>> Have you explored other options, "port-0", "port-1" ?
>>>
>>
>> I think it's much better. Will update in next version.
> 
> I am not sure if there exists a better scheme for identifying or
> numbering the interrupts. Happy to listen to the DT experts.
> 
> Rob, Krzysztof, thoughts ?
> 

Hi Suzuki,

I was thinking how about the name "ETRIRQ0", "ETRIRQ1" etc...

Thanks,
Jie

> Suzuki
> 
> 
>>
>> Thanks,
>> Jie
>>
>>> Suzuki
>>>
>>>> +
>>>>     in-ports:
>>>>       $ref: /schemas/graph.yaml#/properties/ports
>>>> @@ -56,6 +66,8 @@ additionalProperties: false
>>>>   examples:
>>>>     - |
>>>> +    #include <dt-bindings/interrupt-controller/arm-gic.h>
>>>> +
>>>>       ctcu at 1001000 {
>>>>           compatible = "qcom,sa8775p-ctcu";
>>>>           reg = <0x1001000 0x1000>;
>>>> @@ -63,6 +75,11 @@ examples:
>>>>           clocks = <&aoss_qmp>;
>>>>           clock-names = "apb";
>>>> +        interrupts = <GIC_SPI 270 IRQ_TYPE_EDGE_RISING>,
>>>> +                     <GIC_SPI 262 IRQ_TYPE_EDGE_RISING>;
>>>> +        interrupt-names = "etr0",
>>>> +                          "etr1";
>>>> +
>>>>           in-ports {
>>>>               #address-cells = <1>;
>>>>               #size-cells = <0>;
>>>>
>>>
>>>
>>
>