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Message-ID: <fc685f00-41e5-e64c-09b8-662b01a46f6c@linaro.org>
Date:   Wed, 29 Jun 2022 12:07:16 +0200
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Subject: Re: [PATCH 1/4] dt-bindings: misc: tmr-manager: Add device-tree
 binding for TMR Manager
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To:     Appana Durga Kedareswara rao <appana.durga.rao@xilinx.com>,
        robh+dt@kernel.org, krzysztof.kozlowski+dt@linaro.org,
        devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
        michal.simek@xilinx.com, derek.kiernan@xilinx.com,
        dragan.cvetic@xilinx.com, arnd@arndb.de,
        gregkh@linuxfoundation.org, linux-arm-kernel@lists.infradead.org
Cc:     git@amd.com, git@xilinx.com
References: <20220628054338.1631516-1-appana.durga.rao@xilinx.com>
 <20220628054338.1631516-2-appana.durga.rao@xilinx.com>
From:   Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
In-Reply-To: <20220628054338.1631516-2-appana.durga.rao@xilinx.com>
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On 28/06/2022 07:43, Appana Durga Kedareswara rao wrote:
> This commit adds documentation for Triple Modular Redundancy(TMR) Manager
> IP. The Triple Modular Redundancy(TMR) Manager is responsible for handling
> the TMR subsystem state, including fault detection and error recovery
> provides soft error detection, correction and recovery features.
> 
> Signed-off-by: Appana Durga Kedareswara rao <appana.durga.rao@xilinx.com>
> ---
>  .../bindings/misc/xlnx,tmr-manager.yaml       | 48 +++++++++++++++++++

This is not a misc device. Find appropriate subsystem for it. It's not
EDAC, right?

>  1 file changed, 48 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/misc/xlnx,tmr-manager.yaml
> 
> diff --git a/Documentation/devicetree/bindings/misc/xlnx,tmr-manager.yaml b/Documentation/devicetree/bindings/misc/xlnx,tmr-manager.yaml
> new file mode 100644
> index 000000000000..f6cb4d235981
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/misc/xlnx,tmr-manager.yaml
> @@ -0,0 +1,48 @@
> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/misc/xlnx,tmr-manager.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Xilinx TMR Microblaze Device Tree Bindings

s/Device Tree Bindings//

> +
> +maintainers:
> +  - Appana Durga Kedareswara rao <appana.durga.rao@xilinx.com>
> +
> +description: |
> +  The Triple Modular Redundancy(TMR) Manager is responsible for handling the
> +  TMR subsystem state, including fault detection and error recovery. The core
> +  is triplicated in each of the sub-blocks in the TMR subsystem, and provides
> +  majority voting of its internal state.
> +
> +properties:
> +  compatible:
> +    enum:
> +      - xlnx,tmr-manager-1.0
> +
> +  reg:
> +    maxItems: 1
> +
> +  xlnx,magic1:
> +    minimum: 0
> +    maximum: 255
> +    description:
> +      Magic number 1, When writing to the control register the first write data
> +      byte (bits 7:0) must match this value in order to have any effect on the
> +      nominal recovery function.

Register values are usually not in the scope of bindings. We describe
here hardware, not programming model, although in case of soft cores
maybe it's a bit different.

Anyway you need to describe the actual feature, not OS behavior.

> +    $ref: /schemas/types.yaml#/definitions/uint32
> +
> +required:
> +  - compatible
> +  - reg
> +  - xlnx,magic1
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    tmr-manager@44a10000 {

Depending on what is this, you should use appropriate generic node name.

> +            compatible = "xlnx,tmr-manager-1.0";
> +            reg = <0x44a10000 0x10000>;
> +            xlnx,magic1 = <0x46>;
> +    };


Best regards,
Krzysztof