Re: [PATCH net-next 02/11] net: dsa: tag_rzn1_a5psw: Add RZ/T2H ETHSW tag protocol and register ethsw tag driver

Vladimir Oltean
2025-11-21T19:27:06Z

On Fri, Nov 21, 2025 at 11:35:28AM +0000, Prabhakar wrote:
> From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
>
> Add an explicit tag protocol for the RZ/T2H ETHSW and register a separate
> ethsw tag driver so the existing A5PSW tag implementation can be reused
> for RZ/T2H without code duplication.
>
> The ETHSW IP on RZ/T2H shares substantial commonality with the A5PSW IP on
> RZ/N1, and the current tag driver does not touch the register fields that
> differ between the two blocks.

Tagging protocol drivers are specifically written to not deal with
register fields. I would like a clarification that this is a phrasing
mistake and you mean the packet header fields that differ between the
ETHSW and the A5PSW tag format.

> Expose a distinct DSA protocol and a second dsa_device_ops to let
> consumers select the RZ/T2H tag format while keeping the proven A5PSW
> handling unchanged.
>
> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> ---