Re: [PATCH 2/7] dt-bindings: pci: Add document for ASPEED PCIe Config

[Krzysztof Kozlowski]

On 13/06/2025 05:29, Jacky Chou wrote:
> Add device tree binding documentation for the ASPEED AST2600/AST2700 PCIe
> configuration syscon block. This shared register space is used by multiple
> PCIe-related devices to coordinate and manage common PCIe settings.
> The binding describes the required compatible strings and register space
> for the configuration node.
> 
> Signed-off-by: Jacky Chou <jacky_chou@xxxxxxxxxxxxxx>
> ---
>  .../bindings/pci/aspeed-pcie-cfg.yaml         | 41 +++++++++++++++++++
>  1 file changed, 41 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/pci/aspeed-pcie-cfg.yaml
> 
> diff --git a/Documentation/devicetree/bindings/pci/aspeed-pcie-cfg.yaml b/Documentation/devicetree/bindings/pci/aspeed-pcie-cfg.yaml
> new file mode 100644
> index 000000000000..6b51eedf4c47
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/pci/aspeed-pcie-cfg.yaml
> @@ -0,0 +1,41 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/pci/aspeed-pcie-cfg.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: ASPEED PCIe Configuration
> +
> +maintainers:
> +  - Jacky Chou <jacky_chou@xxxxxxxxxxxxxx>
> +
> +description: |
> +  The ASPEED PCIe configuration syscon block provides a set of registers shared

How is this a pci device? You just described syscon, so this goes to soc.

All other comments apply as well.

> +  by multiple PCIe-related devices within the SoC. This node represents the
> +  common configuration space that allows these devices to coordinate and manage
> +  shared PCIe settings, including address mapping, control, and status
> +  registers. The syscon interface enables Linux drivers for various PCIe devices

Do not describe OS. Describe the hardware and drop Linux drivers completely.

> +  to access  and modify these shared registers in a consistent and centralized
> +  manner.
> +
> +properties:
> +  compatible:
> +    enum:
> +      - aspeed,ast2600-pcie-cfg
> +      - aspeed,ast2700-pcie-cfg
> +
> +  reg:
> +    maxItems: 1
> +
> +required:
> +  - compatible
> +  - reg
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    pcie-cfg@1e770000 {

Node names should be generic. See also an explanation and list of
examples (not exhaustive) in DT specification:
https://devicetree-specification.readthedocs.io/en/latest/chapter2-devicetree-basics.html#generic-names-recommendation

Look how syscons are called in other vendors.

> +      compatible = "aspeed,ast2600-pcie-cfg";
> +      reg = <0x1e770000 0x80>;
> +    };


Best regards,
Krzysztof