Re: [PATCH V6 1/3] dt-bindings: sram: qcom,imem: Add Boot Stat region within IMEM

[Souradeep Chowdhury]

On 5/9/2023 5:05 PM, Dmitry Baryshkov wrote:
> On Tue, 9 May 2023 at 13:53, Souradeep Chowdhury
> <quic_schowdhu@xxxxxxxxxxx> wrote:
> > All Qualcomm bootloaders log useful timestamp information related
> > to bootloader stats in the IMEM region. Add the child node within
> > IMEM for the boot stat region containing register address and
> > compatible string.
>
> I might have a minor vote here. Is there any reason why you have to
> instantiate the device from DT?
> It looks like a software interface. Ideally software should not be
> described in DT (e.g. this can be instantiated from imem
> driver-to-be).
> Or we can follow the RPM master-stats approach, where the device is a
> top-level device, having handle pointers to the sram regions.

This is a dedicated region of IMEM reserved for storing stats related 
information. So it is represented as a child of IMEM, please
refer to Documentation/devicetree/bindings/sram/sram.yaml which
follows a similar philosophy. Also since this is a child of IMEM with
a specific purpose, does it not warrant a dedicated driver?

> > Signed-off-by: Souradeep Chowdhury <quic_schowdhu@xxxxxxxxxxx>
> > Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx>
> > ---
> >   .../devicetree/bindings/sram/qcom,imem.yaml   | 22 +++++++++++++++++++
> >   1 file changed, 22 insertions(+)
> >
> > diff --git a/Documentation/devicetree/bindings/sram/qcom,imem.yaml b/Documentation/devicetree/bindings/sram/qcom,imem.yaml
> > index 0548e8e0d30b..bb884c5c8952 100644
> > --- a/Documentation/devicetree/bindings/sram/qcom,imem.yaml
> > +++ b/Documentation/devicetree/bindings/sram/qcom,imem.yaml
> > @@ -50,6 +50,28 @@ patternProperties:
> >       $ref: /schemas/remoteproc/qcom,pil-info.yaml#
> >       description: Peripheral image loader relocation region
> >
> > +  "^stats@[0-9a-f]+$":
> > +    type: object
> > +    description:
> > +      Imem region dedicated for storing timestamps related
> > +      information regarding bootstats.
> > +
> > +    additionalProperties: false
> > +
> > +    properties:
> > +      compatible:
> > +        items:
> > +          - enum:
> > +              - qcom,sm8450-bootstats
> > +          - const: qcom,imem-bootstats
> > +
> > +      reg:
> > +        maxItems: 1
> > +
> > +    required:
> > +      - compatible
> > +      - reg
> > +
> >   required:
> >     - compatible
> >     - reg
> > --
> > 2.17.1