On Mon, Feb 15, 2021 at 02:47:56PM +0100, Marek Behun wrote: > On Mon, 15 Feb 2021 06:15:59 +0000 > Nathan Rossi <nat...@nathanrossi.com> wrote: > > > diff --git a/drivers/net/dsa/mv88e6xxx/chip.c > > b/drivers/net/dsa/mv88e6xxx/chip.c > > index 54aa942eed..5c52906b29 100644 > > --- a/drivers/net/dsa/mv88e6xxx/chip.c > > +++ b/drivers/net/dsa/mv88e6xxx/chip.c > > @@ -650,6 +650,13 @@ static void mv88e6xxx_validate(struct dsa_switch *ds, > > int port, > > if (chip->info->ops->phylink_validate) > > chip->info->ops->phylink_validate(chip, port, mask, state); > > > > + /* Advertise 2500BASEX only if 1000BASEX is not configured, this > > + * prevents phylink_helper_basex_speed from always overriding the > > + * 1000BASEX mode since auto negotiation is always enabled. > > + */ > > + if (state->interface == PHY_INTERFACE_MODE_1000BASEX) > > + phylink_clear(mask, 2500baseX_Full); > > + > > I don't quite like this. This problem should be either solved in > phylink_helper_basex_speed() or somewhere in the mv88e6xxx code, but near > the call to phylink_helper_basex_speed(). > > Putting a solution to the behaviour of phylink_helper_basex_speed() it > into the validate() method when phylink_helper_basex_speed() is called > from a different place will complicate debugging in the future. If > we start solving problems in this kind of way, the driver will become > totally unreadable, IMO.
If we can't switch between 1000base-X and 2500base-X, then we should not be calling phylink_helper_basex_speed() - and only one of those two capabilities should be set in the validation callback. I thought there were DSA switches where we could program the CMODE to switch between these two... -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTP is here! 40Mbps down 10Mbps up. Decent connectivity at last!
