Subject: Re: [PATCH net-next 2/3] dt-bindings: net: renesas-gbeth: Add port-id property

From: Rob Herring <[email-masked]>
Date: Tue, 9 Dec 2025 14:34:06 -0600

On Thu, Dec 04, 2025 at 05:40:27PM +0100, John Madieu wrote:
> Add optional port-id property to identify ethernet ports on RZ/V2H
> SoCs. The hardware doesn't provide unique identification registers
> for multiple ethernet instances, so this property allows explicit
> port identification from the device tree.
> 
> Signed-off-by: John Madieu <[email-masked]>
> ---
>  .../bindings/net/renesas,rzv2h-gbeth.yaml     | 19 +++++++++++++++++++
>  1 file changed, 19 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/net/renesas,rzv2h-gbeth.yaml b/Documentation/devicetree/bindings/net/renesas,rzv2h-gbeth.yaml
> index bd53ab300f500..bb59c6a925d3f 100644
> --- a/Documentation/devicetree/bindings/net/renesas,rzv2h-gbeth.yaml
> +++ b/Documentation/devicetree/bindings/net/renesas,rzv2h-gbeth.yaml
> @@ -117,6 +117,23 @@ properties:
>            - description: AXI power-on system reset
>            - description: AHB reset
>  
> +  renesas,port-id:
> +    $ref: /schemas/types.yaml#/definitions/uint32
> +    description:
> +      Optional unique port identifier for this ethernet interface.
> +      Used for physical port identification (phys_port_id, phys_port_name).
> +      If not specified, the ethernet alias index is used as fallback.

We already have a common way with aliases, why do we want a vendor 
specific way?

> +    minimum: 0
> +    maximum: 255
> +
> +  renesas,port-name:
> +    $ref: /schemas/types.yaml#/definitions/string
> +    description:
> +      Optional custom name for the physical port. Used by
> +      ndo_get_phys_port_name() for interface naming.
> +      If not specified, "p<N>" format is used where N is the port-id
> +      or ethernet alias index.

Other vendors don't want to name their ports?

Maybe 'label' should be used here (for both parts? Generally, the value 
of label shouldn't be an ABI though. So if for example, software needs 
to find the 'mgmt' port then we should find another way to define that.

Rob