On Mon, Sep 25, 2017 at 01:13:43PM +0100, Russell King - ARM Linux wrote: > On Mon, Sep 25, 2017 at 01:53:03PM +0200, Antoine Tenart wrote: > > On Mon, Sep 25, 2017 at 11:45:32AM +0100, Russell King - ARM Linux wrote: > > > Can you describe what the GoP link IRQ is doing please? > > > > In cases where there is no PHY connected to the MAC and no SFP cage is > > used. One example is when a SOHO switch is connected directly to a > > serdes lane. In such cases we still need to have a minimal link > > management. The GoP link interrupt helps doing so as it raises when the > > serdes is in sync and AN succeeded. > > Isn't this just like a fixed link scenario, or an in-band > autonegotiation scenario (both of which phylink supports natively)? > > The situation on Clearfog with the 88E6176 switch is pretty similar - > a switch connected directly via serdes to the MAC. Currently, we > configure stuff there as a fixed link, but in actual fact the 88E6176 > is configured to run the CPU facing port in 1000base-X mode, and with > appropriate tweaks, switching phylink to 1000base-X mode also works.
Hmm, I think you're right, we should be able to represent the link between the MAC and the switch as a fixed link. And when it's not fixed, it could be done with in-band AN. I cannot test this myself but I've asked someone who can to. Antoine -- Antoine Ténart, Free Electrons Embedded Linux and Kernel engineering http://free-electrons.com