Subject: Re: [PATCH net-next v2] net: airoha: select QDMA block according LAN/WAN configuration

From: Simon Horman <[email-masked]>
Date: Tue, 17 Mar 2026 14:31:41 +0000

On Fri, Mar 13, 2026 at 05:28:36PM +0100, Lorenzo Bianconi wrote:
> Before this patch even GDM ports were assigned to QDMA0 while odd GDM
> ports were using QDMA1, so, based on the DTS configuration, both QDMA0
> and QDMA1 can theoretically receive traffic destinated to the host cpu
> from LAN or WAN GDM ports.
> Airoha folks reported the hw design assumes the LAN traffic destinated
> to the host cpu is be forwarded to QDMA0 while traffic received on WAN
> GDM port is managed by QDMA1. For this reason, select QDMA block according
> to the GDM port LAN or WAN configuration:
> - QDMA0 is used for GDM LAN devices
> - QDMA1 is used for GDM WAN device
> 
> Assuming a device with three GDM ports, a typical configuration could be:
> - MT7530 DSA switch -> GDM1 (eth0) -> QDMA0 (LAN traffic)
> - External PHY      -> GDM2 (eth1) -> QDMA1 (WAN traffic)
> - External PHY      -> GDM3 (eth2) -> QDMA0 (LAN traffic)
> 
> We can then bridge eth0 DSA port (lanX) with eth2 since they all tx/rx
> LAN traffic.
> 
> Please note this patch introduces a change not visible to the user since
> airoha_eth driver currently supports just the internal phy available via
> the MT7530 DSA switch and there are no WAN interfaces officially supported
> since PCS/external phy is not merged mainline yet (it will be posted with
> following patches).
> 
> Signed-off-by: Lorenzo Bianconi <[email-masked]>
> ---
> Changes in v2:
> - Update commit log.
> - Link to v1: https://lore.kernel.org/r/[email-masked]

Thanks for the update.

Reviewed-by: Simon Horman <[email-masked]>