Subject: Re: Marvell switch port shows LOWERLAYERDOWN, ping fails

From: Andrew Lunn <[email-masked]>
Date: Wed, 28 Jul 2021 22:47:07 +0200

> Many thanks for the link; I will build and install it on the target. Hope it
> will work with the older kernel (5.4.114) we're using.

Probably not. You need

commit b71a8d60252111d89dccba92ded7470faef16460
Author: Andrew Lunn <[email-masked]>
Date:   Sun Oct 4 18:12:57 2020 +0200

    net: dsa: mv88e6xxx: Add per port devlink regions
    
    Add a devlink region to return the per port registers.
    
    Signed-off-by: Andrew Lunn <[email-masked]>
    Reviewed-by: Florian Fainelli <[email-masked]>
    Reviewed-by: Vladimir Oltean <[email-masked]>
    Signed-off-by: David S. Miller <[email-masked]>

5.4 we released in 2019-11-24.

When debugging issues like this, you really should be using a modern
kernel. At minimum 5.13, better still, net-next.

	Andrew