Re: [PATCH 1/5] dt-bindings: pci: Add Sophgo SG2042 PCIe host

[Rob Herring <robh@kernel.org>]

On Mon, Nov 11, 2024 at 01:59:37PM +0800, Chen Wang wrote:
> From: Chen Wang <unicorn_wang@outlook.com>
> 
> Add binding for Sophgo SG2042 PCIe host controller.
> 
> Signed-off-by: Chen Wang <unicorn_wang@outlook.com>
> ---
>  .../bindings/pci/sophgo,sg2042-pcie-host.yaml | 88 +++++++++++++++++++
>  1 file changed, 88 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/pci/sophgo,sg2042-pcie-host.yaml
> 
> diff --git a/Documentation/devicetree/bindings/pci/sophgo,sg2042-pcie-host.yaml b/Documentation/devicetree/bindings/pci/sophgo,sg2042-pcie-host.yaml
> new file mode 100644
> index 000000000000..d4d2232f354f
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/pci/sophgo,sg2042-pcie-host.yaml
> @@ -0,0 +1,88 @@
> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/pci/sophgo,sg2042-pcie-host.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Sophgo SG2042 PCIe Host (Cadence PCIe Wrapper)
> +
> +description: |+

Don't need '|+'

> +  Sophgo SG2042 PCIe host controller is based on the Cadence PCIe core.

> +  It shares common features with the PCIe core and inherits common properties
> +  defined in Documentation/devicetree/bindings/pci/cdns-pcie-host.yaml.

That's clear from the $ref. No need to say that in prose.

> +
> +maintainers:
> +  - Chen Wang <unicorn_wang@outlook.com>
> +
> +properties:
> +  compatible:
> +    const: sophgo,sg2042-pcie-host
> +
> +  reg:
> +    maxItems: 2
> +
> +  reg-names:
> +    items:
> +      - const: reg
> +      - const: cfg
> +
> +  sophgo,syscon-pcie-ctrl:
> +    $ref: /schemas/types.yaml#/definitions/phandle
> +    description: Phandle to the SYSCON entry

Please describe what you need to access.

> +
> +  sophgo,link-id:
> +    $ref: /schemas/types.yaml#/definitions/uint32
> +    description: Cadence IP link ID.

Is this an index or related to the syscon? Nak for the former, use 
linux,pci-domain. For the latter, add an arg to sophgo,syscon-pcie-ctrl.

> +
> +  sophgo,internal-msi:
> +    $ref: /schemas/types.yaml#/definitions/flag
> +    description: Identifies whether the PCIE node uses internal MSI controller.

Wouldn't 'msi-parent' work for this purpose?

> +
> +  vendor-id:
> +    const: 0x1f1c
> +
> +  device-id:
> +    const: 0x2042
> +
> +  interrupts:
> +    maxItems: 1
> +
> +  interrupt-names:
> +    const: msi
> +
> +allOf:
> +  - $ref: cdns-pcie-host.yaml#
> +
> +required:
> +  - compatible
> +  - reg
> +  - reg-names
> +  - sophgo,syscon-pcie-ctrl
> +  - sophgo,link-id
> +  - vendor-id
> +  - device-id
> +  - ranges

ranges is already required in the common schemas.

> +
> +additionalProperties: true
> +
> +examples:
> +  - |
> +    pcie@62000000 {
> +      compatible = "sophgo,sg2042-pcie-host";
> +      device_type = "pci";
> +      reg = <0x62000000  0x00800000>,
> +            <0x48000000  0x00001000>;
> +      reg-names = "reg", "cfg";
> +      #address-cells = <3>;
> +      #size-cells = <2>;
> +      ranges = <0x81000000 0 0x00000000 0xde000000 0 0x00010000>,
> +               <0x82000000 0 0xd0400000 0xd0400000 0 0x0d000000>;
> +      bus-range = <0x80 0xbf>;
> +      vendor-id = <0x1f1c>;
> +      device-id = <0x2042>;
> +      cdns,no-bar-match-nbits = <48>;
> +      sophgo,link-id = <0>;
> +      sophgo,syscon-pcie-ctrl = <&cdns_pcie1_ctrl>;
> +      sophgo,internal-msi;
> +      interrupt-parent = <&intc>;
> +    };
> -- 
> 2.34.1
>