Re: Is it currently possible to connect SFP to dsa port?

[Andrew Lunn <andrew@lunn.ch>]

On Tue, Aug 07, 2018 at 12:43:11PM -0700, Florian Fainelli wrote:
> 
> 
> On 08/07/2018 12:00 PM, Marek Behun wrote:
> > Hello,
> > 
> > I have a question regarding DSA/SFP code.
> > 
> > We are working on a modular router where it is possible to connect
> > multiple switch cards and at most one SFP cage card to a router.
> > 
> > Does the sfp/dsa driver support connecting SFP port to a DSA port? For
> > example the Marvell 6390 switch has two SGMII ports and 8 1Gbps PHYs.
> > One can then connect those 8 1Gbps PHYs to RJ-45 connectors, the first
> > SGMII port to the CPU and the second SGMII port to SFP.
> > 
> > I think this is currently not possible, but am not sure.
> 
> DSA recently gained support for PHYLINK which would allow you to do
> that, please make sure your tree has this commit at least:
> 
> aab9c4067d2389d0adfc9c53806437df7b0fe3d5 ("net: dsa: Plug in PHYLINK
> support").

Hi Florian

That gives enough to not break existing setups using the mv88e6xxx
driver. But to really use PHYLINK, more code is needed. I've taken
some of Russell Kings work, and merged that in, which gives us proper
support for validate, config_mac, etc. But Russell's code is missing
calls to phylink_mac_change, and handling SERDES interfaces, which are
needed for SFPs. I've got some code which is near, but it broke D in
DSA on my board :-(

    Andrew