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

[Mukesh Ojha]

On Fri, May 08, 2026 at 07:09:50AM -0500, Rob Herring wrote:
> 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.
>

Sure, will remove restriction.

> Rob

-- 
-Mukesh Ojha