The 11/26/2021 11:04, Russell King (Oracle) wrote:
>
> On Fri, Nov 26, 2021 at 10:05:37AM +0100, Horatiu Vultur wrote:
> > This patch adds support for netdev and phylink in the switch. The
> > injection + extraction is register based. This will be replaced with DMA
> > accees.
> >
> > Signed-off-by: Horatiu Vultur <horatiu.vultur@xxxxxxxxxxxxx>
>
> This looks mostly good now, thanks. There's one remaining issue:
Thanks for the help!
>
> > +int lan966x_port_pcs_set(struct lan966x_port *port,
> > + struct lan966x_port_config *config)
> > +{
> > + struct lan966x *lan966x = port->lan966x;
> > + bool inband_aneg = false;
> > + bool outband;
> > + int err;
> > +
> > + lan966x_port_link_down(port);
>
> This looks like something the MAC layer should be doing. Phylink won't
> change the interface mode by just calling the PCS - it will do this
> sequence, known as a major reconfiguration:
>
> mac_link_down() (if the link was previously up)
> mac_prepare()
> mac_config()
> if (pcs_config() > 0)
> pcs_an_restart()
> mac_finish()
>
> pcs_config() will also be called thusly:
>
> if (pcs_config() > 0)
> pcs_an_restart()
>
> to change the ethtool advertising mask which changes the inband advert
> or the Autoneg bit, which has an effect only on your DEV_PCS1G_ANEG_CFG()
> register, and this may be called with the link up or down.
>
> Also, pcs_config() is supposed to return 0 if the inband advert has not
> changed, or positive if it has (so pcs_an_restart() is called to cause
> in-band negotiation to be restarted.)
>
> Note also that pcs_an_restart() may also be called when ethtool
> requests negotiation restart when we're operating in 802.3z modes.
>
> So, my question is - do you need to be so heavy weight with the call to
> lan966x_port_link_down() to take everything down when pcs_config() is
> called, and is it really in the right place through the sequence for
> a major reconfiguration?
Thanks for the detail explanation.
You are right, it doesn't look like it is needed to call
lan966x_port_link_down when pcs_config is called.
I can put the lan966x_port_link_down() inside the mac_link_down() callback.
>
> Thanks.
>
> --
> RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
> FTTP is here! 40Mbps down 10Mbps up. Decent connectivity at last!
--
/Horatiu
