Re: [PATCH v1 net-next] net: dsa: Allow only up to two HSR HW offloaded ports for KSZ9477

From: Andrew Lunn
Date: Tue Jun 18 2024 - 10:10:55 EST


> diff --git a/drivers/net/dsa/microchip/ksz_common.c b/drivers/net/dsa/microchip/ksz_common.c
> index 2818e24e2a51..181e81af3a78 100644
> --- a/drivers/net/dsa/microchip/ksz_common.c
> +++ b/drivers/net/dsa/microchip/ksz_common.c
> @@ -3906,6 +3906,11 @@ static int ksz_hsr_join(struct dsa_switch *ds, int port, struct net_device *hsr,
> return -EOPNOTSUPP;
> }
>
> + if (hweight8(dev->hsr_ports) > 1) {
> + NL_SET_ERR_MSG_MOD(extack, "Cannot offload more than two ports (in use=0x%x)", dev->hsr_ports);
> + return -EOPNOTSUPP;
> + }

Hi Dan

I don't know HSR to well, but this is offloading to hardware, to
accelerate what Linux is already doing in software. It should be, if
the hardware says it cannot do it, software will continue to do the
job. So the extack message should never be seen.

Andrew