Re: [PATCH 1/4] dt-bindings: firmware: qcom,scm: Add minidump SRAM property

[Rob Herring]

On Fri, May 8, 2026 at 5:50 AM Konrad Dybcio
<konrad.dybcio@xxxxxxxxxxxxxxxx> wrote:
>
> On 5/7/26 10:07 AM, Mukesh Ojha wrote:
> > On most Qualcomm SoCs where minidump is supported, a word in always-on
> > SRAM is shared between the kernel and boot firmware. Before DDR is
> > initialised on the warm reset following a crash, firmware reads this
> > word to decide if minidump is enabled and collect a minidump and where
> >  to deliver it (USB upload to a host, or save to local storage).
> >
> > Add 'sram' and 'sram-names' properties to the SCM binding to describe
> > a region in always-on SRAM where the minidump download destination
> > value could be written. Boot firmware reads it before DDR is initialised
> > on a warm reset to decide where to store the minidump either to host
> > PC or to on device storage.
> >
> > Most of the Qualcomm SoC supporting minidump supports this, added the
> > kaanapali SoC for now.
> >
> > Suggested-by: Konrad Dybcio <konrad.dybcio@xxxxxxxxxxxxxxxx>
> > Signed-off-by: Mukesh Ojha <mukesh.ojha@xxxxxxxxxxxxxxxx>
> > ---
> >  .../bindings/firmware/qcom,scm.yaml           | 57 +++++++++++++++++++
> >  1 file changed, 57 insertions(+)
> >
> > diff --git a/Documentation/devicetree/bindings/firmware/qcom,scm.yaml b/Documentation/devicetree/bindings/firmware/qcom,scm.yaml
> > index 7918d31f58b4..6813081fd74a 100644
> > --- a/Documentation/devicetree/bindings/firmware/qcom,scm.yaml
> > +++ b/Documentation/devicetree/bindings/firmware/qcom,scm.yaml
> > @@ -127,6 +127,22 @@ properties:
> >            - description: offset of the download mode control register
> >      description: TCSR hardware block
> >
> > +  sram:
> > +    $ref: /schemas/types.yaml#/definitions/phandle-array
> > +    description:
> > +      Phandle to a region in always-on SRAM used to store the download
> > +      mode value for boot firmware to read before DDR is initialised on
> > +      the next warm reset.
> > +    maxItems: 1
> > +
> > +  sram-names:
> > +    items:
> > +      - const: minidump
> > +
> > +dependencies:
> > +  sram: [ sram-names ]
> > +  sram-names: [ sram ]
> > +
> >  allOf:
> >    # Clocks
> >    - if:
> > @@ -229,6 +245,18 @@ allOf:
> >        properties:
> >          memory-region: false
> >
> > +  - if:
> > +      not:
> > +        properties:
> > +          compatible:
> > +            contains:
> > +              enum:
> > +                - qcom,scm-kaanapali
>
> This list will grow super large - like mentioned in the commit message,
> to list almost all platforms.. I don't know if it makes sense to limit
> this. Krzysztof/Rob?

Probably not. If sram is not valid for a platform, you'd have to go
out of your way to first add it and to have any effect if you did.

Rob