netdev - [RFC] net:dsa: mv88e6xxx: RMU-only mode

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [day] [month] [year] [list]

Message-Id: <1D0097F9-5C25-442C-BDD5-CF8F7D8838E6@padl.com>
Date: Wed, 11 Jun 2025 10:11:27 +1000
From: Luke Howard <lukeh@...l.com>
To: netdev@...r.kernel.org
Subject: [RFC] net:dsa: mv88e6xxx: RMU-only mode

Some Marvell switches have a Remote Management Unit (RMU) which permits in-band configuration, essentially tunnelling MDIO requests in Ethernet packets.

Andrew Lunn and Mattias Forsblad have previously submitted patches to the mv88e6xxx driver to support RMU, with the proviso that MDIO must still be present for initial switch configuration and to enable RMU itself.

There are some situations where MDIO is unavailable, but RMU can be enabled externally (either by an external device connected over MDIO or a switch EEPROM). In this case it is useful to support in-band only configuration, without MDIO, with the switch being a platform device instead of a MDIO child node.

WIP patches can be found here:

https://github.com/PADL/linux/tree/rpi-6.14.y-xebros-rmu

It required changes to both the DSA core (to bring up the conduit device first) as well as the Marvell driver. Once Andrew has submitted his RMU patches on which these are based, and I have done further testing, I plan to submit these patches.

Please note that the tree above includes some unrelated driver commits for AVB and DSCP support that I of course would separate out before submitting.