Re: [PATCH v2] bcm63xx_enet: fix internal phy IRQ assignment

["Daniel González Cabanelas" <dgcbueu@gmail.com>]

El jue, 25 feb 2021 a las 8:22, Heiner Kallweit
(<hkallweit1@gmail.com>) escribió:
>
> On 25.02.2021 00:54, Daniel González Cabanelas wrote:
> > El mié, 24 feb 2021 a las 23:01, Florian Fainelli
> > (<f.fainelli@gmail.com>) escribió:
> >>
> >>
> >>
> >> On 2/24/2021 1:44 PM, Heiner Kallweit wrote:
> >>> On 24.02.2021 16:44, Daniel González Cabanelas wrote:
> >>>> The current bcm63xx_enet driver doesn't asign the internal phy IRQ. As a
> >>>> result of this it works in polling mode.
> >>>>
> >>>> Fix it using the phy_device structure to assign the platform IRQ.
> >>>>
> >>>> Tested under a BCM6348 board. Kernel dmesg before the patch:
> >>>>    Broadcom BCM63XX (1) bcm63xx_enet-0:01: attached PHY driver [Broadcom
> >>>>               BCM63XX (1)] (mii_bus:phy_addr=bcm63xx_enet-0:01, irq=POLL)
> >>>>
> >>>> After the patch:
> >>>>    Broadcom BCM63XX (1) bcm63xx_enet-0:01: attached PHY driver [Broadcom
> >>>>               BCM63XX (1)] (mii_bus:phy_addr=bcm63xx_enet-0:01, irq=17)
> >>>>
> >>>> Pluging and uplugging the ethernet cable now generates interrupts and the
> >>>> PHY goes up and down as expected.
> >>>>
> >>>> Signed-off-by: Daniel González Cabanelas <dgcbueu@gmail.com>
> >>>> ---
> >>>> changes in V2:
> >>>>   - snippet moved after the mdiobus registration
> >>>>   - added missing brackets
> >>>>
> >>>>  drivers/net/ethernet/broadcom/bcm63xx_enet.c | 13 +++++++++++--
> >>>>  1 file changed, 11 insertions(+), 2 deletions(-)
> >>>>
> >>>> diff --git a/drivers/net/ethernet/broadcom/bcm63xx_enet.c b/drivers/net/ethernet/broadcom/bcm63xx_enet.c
> >>>> index fd876721316..dd218722560 100644
> >>>> --- a/drivers/net/ethernet/broadcom/bcm63xx_enet.c
> >>>> +++ b/drivers/net/ethernet/broadcom/bcm63xx_enet.c
> >>>> @@ -1818,10 +1818,19 @@ static int bcm_enet_probe(struct platform_device *pdev)
> >>>>               * if a slave is not present on hw */
> >>>>              bus->phy_mask = ~(1 << priv->phy_id);
> >>>>
> >>>> -            if (priv->has_phy_interrupt)
> >>>> +            ret = mdiobus_register(bus);
> >>>> +
> >>>> +            if (priv->has_phy_interrupt) {
> >>>> +                    phydev = mdiobus_get_phy(bus, priv->phy_id);
> >>>> +                    if (!phydev) {
> >>>> +                            dev_err(&dev->dev, "no PHY found\n");
> >>>> +                            goto out_unregister_mdio;
> >>>> +                    }
> >>>> +
> >>>>                      bus->irq[priv->phy_id] = priv->phy_interrupt;
> >>>> +                    phydev->irq = priv->phy_interrupt;
> >>>> +            }
> >>>>
> >>>> -            ret = mdiobus_register(bus);
> >>>
> >>> You shouldn't have to set phydev->irq, this is done by phy_device_create().
> >>> For this to work bus->irq[] needs to be set before calling mdiobus_register().
> >>
> >> Yes good point, and that is what the unchanged code does actually.
> >> Daniel, any idea why that is not working?
> >
> > Hi Florian, I don't know. bus->irq[] has no effect, only assigning the
> > IRQ through phydev->irq works.
> >
> > I can resend the patch  without the bus->irq[] line since it's
> > pointless in this scenario.
> >
>
> It's still an ugly workaround and a proper root cause analysis should be done
> first. I can only imagine that phydev->irq is overwritten in phy_probe()
> because phy_drv_supports_irq() is false. Can you please check whether
> phydev->irq is properly set in phy_device_create(), and if yes, whether
> it's reset to PHY_POLL in phy_probe()?.
>

Hi Heiner, I added some kernel prints:

[    2.712519] libphy: Fixed MDIO Bus: probed
[    2.721969] =======phy_device_create===========
[    2.726841] phy_device_create: dev->irq = 17
[    2.726841]
[    2.832620] =======phy_probe===========
[    2.836846] phy_probe: phydev->irq = 17
[    2.840950] phy_probe: phy_drv_supports_irq = 0, phy_interrupt_is_valid = 1
[    2.848267] phy_probe: phydev->irq = -1
[    2.848267]
[    2.854059] =======phy_probe===========
[    2.858174] phy_probe: phydev->irq = -1
[    2.862253] phy_probe: phydev->irq = -1
[    2.862253]
[    2.868121] libphy: bcm63xx_enet MII bus: probed
[    2.873320] Broadcom BCM63XX (1) bcm63xx_enet-0:01: attached PHY
driver [Broadcom BCM63XX (1)] (mii_bus:phy_addr=bcm63xx_enet-0:01,
irq=POLL)

Currently using kernel 5.4.99. I still have no idea what's going on.

> On which kernel version do you face this problem?
>
The kernel version 4.4 works ok. The minimum version where I found the
problem were the kernel 4.9.111, now using 5.4. And 5.10 also tested.

Regards
Daniel

> > Regards
> >> --
> >> Florian
>