[EXT] Re: [PATCH v3 1/4] dt-bindings: soc: imx8m: add DT Binding doc for soc unique ID

[Alice Guo]

> -----Original Message-----
> From: Krzysztof Kozlowski <krzk at kernel.org>
> Sent: 2020年11月15日 0:50
> To: Alice Guo <alice.guo at nxp.com>
> Cc: robh+dt at kernel.org; shawnguo at kernel.org; s.hauer at pengutronix.de;
> dl-linux-imx <linux-imx at nxp.com>; Peng Fan <peng.fan at nxp.com>;
> devicetree at vger.kernel.org; linux-kernel at vger.kernel.org;
> linux-arm-kernel at lists.infradead.org
> Subject: [EXT] Re: [PATCH v3 1/4] dt-bindings: soc: imx8m: add DT Binding doc
> for soc unique ID
> 
> Caution: EXT Email
> 
> On Fri, Nov 13, 2020 at 07:04:06PM +0800, Alice Guo wrote:
> > Add DT Binding doc for the Unique ID of i.MX 8M series.
> >
> > Signed-off-by: Alice Guo <alice.guo at nxp.com>
> > ---
> >  .../devicetree/bindings/arm/fsl.yaml          | 25
> +++++++++++++++++++
> >  1 file changed, 25 insertions(+)
> >
> > diff --git a/Documentation/devicetree/bindings/arm/fsl.yaml
> > b/Documentation/devicetree/bindings/arm/fsl.yaml
> > index e4db0f9ed664..f4faebbb57da 100644
> > --- a/Documentation/devicetree/bindings/arm/fsl.yaml
> > +++ b/Documentation/devicetree/bindings/arm/fsl.yaml
> > @@ -901,6 +901,31 @@ properties:
> >                - fsl,s32v234-evb           # S32V234-EVB2 Customer
> Evaluation Board
> >            - const: fsl,s32v234
> >
> > +  soc:
> > +    type: object
> > +    properties:
> > +      compatible:
> > +        oneOf:
> > +          - description: i.MX8M SoCs
> > +            items:
> > +              - enum:
> > +                  - fsl,imx8mm-soc
> > +                  - fsl,imx8mn-soc
> > +                  - fsl,imx8mp-soc
> > +                  - fsl,imx8mq-soc
> > +              - const: simple-bus
> > +
> > +          - description: Other SoCs
> > +            items:
> > +              - const: simple-bus
> > +
> > +      nvmem-cells:
> > +        maxItems: 1
> > +        description: Phandle to the SOC Unique ID provided by a nvmem
> > + node
> > +
> > +      nvmem-cells-names:
> > +        const: soc_unique_id
> > +
> >  additionalProperties: true
> 
> The "soc" node should be required for these compatibles. Otherwise you will
> have to stay with this backwards-compatible-DTB-device-initcall-glue for many
> years... I think you can achieve it with allOf.
> 
[Alice Guo]Hi,
I find that my description for compatible is ambiguous. There are two kinds of compatible of the "soc" node:
1. For dtsi files used for SoCs other than imx8m series SoCs and old version dtsi files used for imx8m series SoCs,
compatible of the "soc" node is "simple-bus".
2. For new version dtsi files used for imx8m series SoCs, compatible of the "soc" node is {"fsl,imx8mX-soc","simple-bus"}.

"nvmem-cell" is an optional property.

I do not understand what you mean. You mean that limit the compatible of "soc" node must include " fsl,imx8mX-soc" in new version dts files. Is my understanding correct?

Best regards,
Alice

> Best regards,
> Krzysztof