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Date:   Sat, 27 Mar 2021 10:30:06 -0600
From:   Rob Herring <robh@kernel.org>
To:     Cristian Ciocaltea <cristian.ciocaltea@gmail.com>
Cc:     Andreas =?iso-8859-1?Q?F=E4rber?= <afaerber@suse.de>,
        Manivannan Sadhasivam <mani@kernel.org>,
        devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        linux-actions@lists.infradead.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 1/4] dt-bindings: soc: actions: Add Actions Semi Owl
 socinfo binding
Message-ID: <20210327163006.GA185779@robh.at.kernel.org>
References: <cover.1616178258.git.cristian.ciocaltea@gmail.com>
 <95105518f61408743d17783099ed9c373a3dfe18.1616178258.git.cristian.ciocaltea@gmail.com>
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On Fri, Mar 19, 2021 at 08:27:59PM +0200, Cristian Ciocaltea wrote:
> Add devicetree binding for the Actions Semi Owl SoCs info module.
> 
> Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea@gmail.com>
> ---
>  .../bindings/soc/actions/owl-socinfo.yaml     | 71 +++++++++++++++++++
>  1 file changed, 71 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/soc/actions/owl-socinfo.yaml
> 
> diff --git a/Documentation/devicetree/bindings/soc/actions/owl-socinfo.yaml b/Documentation/devicetree/bindings/soc/actions/owl-socinfo.yaml
> new file mode 100644
> index 000000000000..3fcb1f584fdf
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/soc/actions/owl-socinfo.yaml
> @@ -0,0 +1,71 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/soc/actions/owl-socinfo.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Actions Semi Owl SoC info module
> +
> +maintainers:
> +  - Cristian Ciocaltea <cristian.ciocaltea@gmail.com>
> +
> +description: |
> +  Actions Semi Owl SoC info module provides access to various information
> +  about the S500, S700 and S900 SoC variants, such as serial number or id.
> +
> +patternProperties:
> +  "^soc(@[0-9a-f]+)?$":

Make this a $nodename property.

> +    type: object
> +    properties:

And move this up to top-level.

You need a custom 'select' entry to exclude 'simple-bus'.

> +      compatible:
> +        items:
> +          - enum:
> +              - actions,s500-soc
> +              - actions,s700-soc
> +              - actions,s900-soc
> +          - const: simple-bus
> +
> +      "#address-cells":
> +        enum: [1, 2]
> +
> +      "#size-cells":
> +        enum: [1, 2]
> +
> +      ranges: true
> +
> +      actions,serial-number-addrs:
> +        description: |
> +          Contains the physical addresses in DDR memory where the two parts
> +          of the serial number (low & high) can be read from.
> +          This is currently supported only on the S500 SoC variant.
> +        $ref: /schemas/types.yaml#/definitions/uint32-array
> +        minItems: 2
> +        maxItems: 2

Humm, it doesn't really seem you have an actual device or bus here, but 
are abusing DT to create your socinfo device.

As the only property is data in main memory, you should do a compatible 
for that memory region and put it under reserved-memory. You need that 
anyway to prevent the kernel from using the memory, right?

Rob