Hi Andrew,
On Mon, 11 Sep 2017 14:00:09 +0200 Andrew Lunn <and...@lunn.ch> wrote:
> > > > +static irqreturn_t ave_interrupt(int irq, void *netdev)
> > > > +{
> > > > + struct net_device *ndev = (struct net_device *)netdev;
> > > > + struct ave_private *priv = netdev_priv(ndev);
> > > > + u32 gimr_val, gisr_val;
> > > > +
> > > > + gimr_val = ave_irq_disable_all(ndev);
> > > > +
> > > > + /* get interrupt status */
> > > > + gisr_val = ave_r32(ndev, AVE_GISR);
> > > > +
> > > > + /* PHY */
> > > > + if (gisr_val & AVE_GI_PHY) {
> > > > + ave_w32(ndev, AVE_GISR, AVE_GI_PHY);
> > > > + if (priv->internal_phy_interrupt)
> > > > + phy_mac_interrupt(ndev->phydev,
> > > > ndev->phydev->link);
> > >
> > > Humm. I don't think this is correct. You are supposed to give it the
> > > new link state, not the old.
> > >
> > > What does a PHY interrupt mean here?
> >
> > In the general case, I think PHY events like changing link state are
> > transmitted
> > to CPU as interrupt via interrupt controller, then PHY driver itself can
> > handle
> > the interrupt.
> >
> > And in this case, PHY events are transmitted to MAC as one of its interrupt
> > factor,
> > then I thought that MAC driver had to tell the events to PHY.
>
> Could this be in-band SGMI signalling from the PHY to the MAC? Does
> the documentation give examples of when this interrupt will happen?
>
> Andrew
Unfortunately this MAC doesn't support SGMII.
And there aren't any examples of when this interrupt will happen.
This interrupt happens after ave_open() is called and link is established.
However, I found that auto negotiation didn't start when this interrupt wasn't
handled.
Although ave_init() calls phy_start_aneg(), it doesn't make sense
because phy driver doesn't start yet.
And according to Florian's comment in ave_init(),
> + phy_start_interrupts(phydev);
> +
> + phy_start_aneg(phydev);
>
> No, no, phy_start() would take care of all of that correctly for you,
> you don't have have to do it just there because ave_open() eventually
> calls phy_start() for you, so just drop these two calls.
When moving phy_start_aneg() to ave_open(), the handler doesn't need to call
phy_mac_interrupt() and I can remove it from the handler.
---
Best Regards,
Kunihiko Hayashi
