Re: [PATCH v2 3/4] dt-bindings: PCI: Add UltraRISC DP1000 PCIe controller

[Krzysztof Kozlowski]

On Tue, Apr 07, 2026 at 10:40:54AM +0800, Jia Wang wrote:
> Add UltraRISC DP1000 SoC PCIe controller devicetree bindings.
> 
> Signed-off-by: Jia Wang <wangjia@xxxxxxxxxxxxx>
> ---
>  .../bindings/pci/ultrarisc,dp1000-pcie.yaml        | 103 +++++++++++++++++++++
>  1 file changed, 103 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/pci/ultrarisc,dp1000-pcie.yaml b/Documentation/devicetree/bindings/pci/ultrarisc,dp1000-pcie.yaml
> new file mode 100644
> index 000000000000..d0517130e127
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/pci/ultrarisc,dp1000-pcie.yaml
> @@ -0,0 +1,103 @@
> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/pci/ultrarisc,dp1000-pcie.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: UltraRISC DP1000 PCIe Host Controller
> +
> +description: |

Do not need '|' unless you need to preserve formatting.

> +  UltraRISC DP1000 SoC PCIe host controller is based on the DesignWare PCIe IP.
> +  This binding describes the UltraRISC specific extensions to the base
> +  DesignWare PCIe binding.

Drop sentence. Do not describe in description what the binding
describes. It's circular / repetitive. Just describe that.

> +
> +maintainers:
> +  - Xincheng Zhang <zhangxincheng@xxxxxxxxxxxxx>
> +  - Jia Wang <wangjia@xxxxxxxxxxxxx>
> +
> +allOf:
> +  - $ref: /schemas/pci/snps,dw-pcie.yaml#
> +
> +properties:
> +  compatible:
> +    const: ultrarisc,dp1000-pcie
> +
> +  reg:
> +    items:
> +      - description: Data Bus Interface (DBI) registers.
> +      - description: PCIe configuration space region.
> +
> +  reg-names:
> +    items:
> +      - const: dbi
> +      - const: config
> +
> +  num-lanes:
> +    $ref: /schemas/types.yaml#/definitions/uint32
> +    enum: [4, 16]
> +    description: Number of lanes to use.
> +
> +  max-link-speed:
> +    $ref: /schemas/types.yaml#/definitions/uint32
> +    const: 4

If const then deducible from the compatible. Drop the property.

> +    description: Maximum PCIe link speed supported.
> +
> +  interrupts:
> +    description: List of interrupt specifiers used by the controller

Drop description. Obvious.

> +    items:
> +      - description: MSI interrupt
> +      - description: Legacy INTA interrupt
> +      - description: Legacy INTB interrupt
> +      - description: Legacy INTC interrupt
> +      - description: Legacy INTD interrupt
> +
> +  interrupt-names:
> +    items:
> +      - const: msi
> +      - const: inta
> +      - const: intb
> +      - const: intc
> +      - const: intd
> +
> +required:
> +  - compatible
> +  - reg
> +  - reg-names
> +  - interrupts
> +  - interrupt-names
> +
> +unevaluatedProperties: false
> +
> +examples:
> +  - |
> +    soc {
> +      #address-cells = <2>;
> +      #size-cells = <2>;
> +
> +      pcie_x16: pcie@21000000 {

Drop unused label

> +        compatible = "ultrarisc,dp1000-pcie";

reg, names and ranges go here. Please follow DTS coding style.

> +        #address-cells = <3>;
> +        #size-cells = <2>;
> +        #interrupt-cells = <1>;
> +        reg = <0x0 0x21000000 0x0 0x01000000>,
> +              <0x0 0x4fff0000 0x0 0x00010000>;
> +        reg-names = "dbi", "config";
> +        device_type = "pci";
> +        dma-coherent;
> +        bus-range = <0x0 0xff>;
> +        num-lanes = <16>;
> +        ranges = <0x81000000  0x0 0x4fbf0000  0x0 0x4fbf0000  0x0 0x00400000>,
> +                 <0x82000000  0x0 0x40000000  0x0 0x40000000  0x0 0x0fbf0000>,
> +                 <0xc3000000 0x40 0x00000000 0x40 0x00000000  0xd 0x00000000>;
> +
> +        max-link-speed = <4>;

Drop, compatible defines this.

Best regards,
Krzysztof