On Wed, 13 Jan 2021 21:21:25 +0000 Russell King - ARM Linux admin <li...@armlinux.org.uk> wrote:
> > Russell, could we, for now, just edit the code so that when > > mv88e6390_serdes_pcs_config > > is being configured with inband mode in 2500base-x, the inband mode > > won't be enabled and the function will print a warning? > > This could come with a Fixes tag so that it is backported to stable. > > I don't see any other easy option, so yes, please do that. Will do. > > Afterwards we can work on refactoring the phylink code so that either > > the driver can inform phylink whether 2500base-x inband AN is supported, > > or maybe we can determine from some documentation or whatnot whether > > inband AN is supported on 2500base-x at all. > > I suspect there is no definitive documentation on exactly what > 2500base-x actually is. I suspect it may just be easier to turn off AN > for 2500base-x everywhere, so at least all Linux systems are compatible > irrespective of the hardware. > > Yes, it means losing pause negotiation, and people will have to > manually set pause on each end. This would need a little refactoring of the phylink_sfp_config function, but I don't think it will be that hard. > One thing that I don't know is whether the GPON SFP ONT modules that > use 2500base-x will still function with AN disabled - although I have > the modules, it appeared that they both needed a connection to the ONU > to switch from 1000base-x to 2500base-x on the host side - and as I > don't have an ONU I can test with, I have no way to check their > behaviour. We have an ISP here in Prague who is willing to lend us some GPON ONU devices to get GPON SFP modules work on Turris. I will ask him if he has one capable of 2.5g and try to borrow it. Marek
