Re: [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@xxxxxxxxxx>
> > > > Signed-off-by: Jie Gan <jie.gan@xxxxxxxxxxxxxxxx>
> > > > ---
> > > >   .../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@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>;