Re: [net-next 8/9] dt-bindings: net: renesas,etheravb: Add optional gPTP phandle for Gen4

[Krzysztof Kozlowski]

On Wed, Jun 10, 2026 at 12:24:31PM +0200, Niklas Söderlund wrote:
> The RAVB module on Gen4 have no gPTP clock as part of the RAVB module
> itself, instead it relies on an external system wide gPTP clock. The
> gPTP clock is shared with RTSN on V4H and RSWITCH on S4.
> 
> Add an optional phandle so that the RAVB driver can find and use the
> gPTP clock. Ideally this should have been an mandatory property but for
> backward compatible it is optional. The RAVB module is capable of
> functioning without it, but can in such cases not provided PTP
> functionality.
> 
> Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@xxxxxxxxxxxx>
> ---
>  .../bindings/net/renesas,etheravb.yaml           | 16 ++++++++++++++++
>  1 file changed, 16 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/net/renesas,etheravb.yaml b/Documentation/devicetree/bindings/net/renesas,etheravb.yaml
> index 1e00ef5b3acd..7bc910ab3ae0 100644
> --- a/Documentation/devicetree/bindings/net/renesas,etheravb.yaml
> +++ b/Documentation/devicetree/bindings/net/renesas,etheravb.yaml
> @@ -122,6 +122,13 @@ properties:
>        Specify when the AVB_LINK signal is active-low instead of normal
>        active-high.
>  
> +  renesas,gptp:

Aren't you duplicating existing timestamper property? Aren't purpose of
both the same?

> +    $ref: /schemas/types.yaml#/definitions/phandle
> +    description:
> +      A phandle to an external gPTP clock for Gen4 platforms. The property is

Explain the purpose of this in the hardware.

> +      optional for backwards compatibility, but without it gPTP timestamps are
> +      disabled as Gen4 have no gPTP as part of the RAVB module itself.
> +

Best regards,
Krzysztof