Re: [PATCH net-next v2 7/9] net: phy: introduce ethtool_phy_ops to get and set phy configuration

From: Maxime Chevallier
Date: Tue Oct 08 2024 - 13:20:13 EST


On Tue, 8 Oct 2024 18:05:05 +0100
"Russell King (Oracle)" <linux@xxxxxxxxxxxxxxx> wrote:

> > What I mean is the ability for users to see, from tools like ethtool,
> > that the MCBin doubleshot's eth0 and eth1 interfaces have 2 ports
> > (copper + sfp), and potentially allow picking which one to use in case
> > both ports are connected.
> >
> > There are mutliple devices out-there with such configurations (some
> > marvell switches for example). Do you not see some value in this ?
>
> Many PHYs that have two media facing ports give configuration of the
> priority between the two interfaces, and yes, there would definitely be
> value in exposing that to userspace, thereby allowing userspace to
> configure the policy there.

Great !

> This would probably be more common than the two-PHY issue that we're
> starting with - as I believe the 88e151x PHYs support exactly the same
> thing when used with a RGMII host interface. The serdes port becomes
> available for "fiber" and it is only 1000base-X there.

True, I've seen several setups with this so far indeed, as well as with
PHYs from other vendors.

> I was trying to work out what the motivation was for this platform.

It also turns out that the MCBin is one of the only boards that has a
permanent spot on my desk, as it's a pretty nice platform to experiment
with various PHY aspects.

>
> Sorry if you mentioned it at NetdevConf and I've forgotten it all,
> it was quite a while ago now!

No worries :)

>
> Thanks!

Thanks for your feedback on that whole topic,

Maxime