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

Alice Guo alice.guo at nxp.com
Tue Nov 17 02:12:16 EST 2020



> -----Original Message-----
> From: Krzysztof Kozlowski <krzk at kernel.org>
> Sent: 2020年11月17日 0:03
> 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: Re: [EXT] Re: [PATCH v3 1/4] dt-bindings: soc: imx8m: add DT Binding
> doc for soc unique ID
> 
> Caution: EXT Email
> 
> On Mon, Nov 16, 2020 at 07:04:13AM +0000, Alice Guo wrote:
> >
> > > -----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?
> 
> All new DTS files should have soc node with "fsl,imx8mX-soc" and this should be
> required by dtschema. The nvmem-cells and related properties do not look like
> optional. From the hardware perspective - they are always present. From the
> driver point of view: they are required and driver will fail to work.

[Alice Guo] 
[Alice Guo] 
+  soc:
+    type: object
+    properties:
+      compatible:
+        oneOf:
+          - description: new version DTS for i.MX8M SoCs
+            items:
+              - enum:
+                  - fsl,imx8mm-soc
+                  - fsl,imx8mn-soc
+                  - fsl,imx8mp-soc
+                  - fsl,imx8mq-soc
+              - const: simple-bus
+
+          - description: other SoCs and old version DTS for i.MX8M 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
+
+    allOf:
+      - if:
+          properties:
+            compatible:
+              contains:
+                enum:
+                  - fsl,imx8mm-soc
+                  - fsl,imx8mn-soc
+                  - fsl,imx8mp-soc
+                  - fsl,imx8mq-soc
+                const: simple-bus
+
+        then:
+          required:
+            - nvmem-cells
+            - nvmem-cells-names

The above is my modification. Is that ok?

Best regards,
Alice
> Best regards,
> Krzysztof



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