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Date:   Fri, 29 May 2020 18:33:40 +0200
From:   Andrew Lunn <andrew@lunn.ch>
To:     Thomas Bogendoerfer <tbogendoerfer@suse.de>
Cc:     Russell King - ARM Linux admin <linux@armlinux.org.uk>,
        "David S. Miller" <davem@davemloft.net>,
        Jakub Kicinski <kuba@kernel.org>, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH net] net: mvpp2: Enable autoneg bypass for
 1000BaseX/2500BaseX ports
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> > By propagated, you mean if the external link is down, the link between
> > the switch and node 1 will also be forced down, at the SERDES level?
> 
> yes
> 
> > And if external ports are down, the nodes cannot talk to each other?
> 
> correct
> 
> > External link down causes the whole in box network to fall apart? That
> > seems a rather odd design.
> 
> as I'm not an expert in ceph, I can't judge. But I'll bring it up.

I guess for a single use appliance this is O.K. But it makes the
hardware unusable as a general purpose server.

Is there a variant of the hardware to be used as a general purpose
server, rather than as a Ceph appliance? If so, does it share the same
DT files?

> > What you are actually interested in is the sync state of the SERDES?
> > The link is up if the SERDES has sync.
> 
> yes, that's what I need. How can I do that ?

Given the current code, you cannot. Now we understand the
requirements, we can come up with some ideas how to do this properly.

      Andrew