Re: PROBLEM: Broken or delayed ethernet on Xilinx ZCU104 since 5.18 (regression)

[Saravana Kannan]

On Fri, Aug 4, 2023 at 1:22 PM Rob Herring <robh@xxxxxxxxxx> wrote:
>
> +Saravana

I'll look into this next week and reply.

-Saravana

>
> On Fri, Aug 4, 2023 at 11:52 AM Nick Bowler <nbowler@xxxxxxxxxx> wrote:
> >
> > On 2023-08-04, Rob Herring <robh@xxxxxxxxxx> wrote:
> > > On Fri, Aug 4, 2023 at 10:54 AM Nick Bowler <nbowler@xxxxxxxxxx> wrote:
> > >> Oh, I get it, to include this driver I need to also enable:
> > >>
> > >>   CONFIG_RESET_CONTROLLER=y
> > >>
> > >> Setting this fixes 6.4.  Perhaps CONFIG_ARCH_ZYNQMP should select it?
> > >
> > > Maybe. Do other platforms do that?
> >
> > Of the ~40 platforms in arch/arm64/Kconfig.platforms, there appear to
> > be 5 that do select it.
>
> Then selecting should be okay. Unless there's a desire for resets to
> remain optional (which is going to rely on the timeout).
>
> > >> However, even with this option enabled, 6.5-rc4 remains broken (no
> > >> change in behaviour wrt. the network device).  I will bisect this
> > >> now.
> > >
> > > It would be good to know why the deferred probe timeout doesn't work.
> > > If you disable modules, the kernel shouldn't wait past late_initcall.
> > > Though this functionality keeps getting tweaked, so I may be off on
> > > the current behavior.
> >
> > I don't know about the deferred probe timeout, but I bisected the 6.5-rc4
> > breakage to this commit:
> >
> >   commit c720a1f5e6ee8cb39c28435efc0819cec84d6ee2
> >   Author: Michal Simek <michal.simek@xxxxxxx>
> >   Date:   Mon May 22 16:59:48 2023 +0200
> >
> >       arm64: zynqmp: Describe TI phy as ethernet-phy-id
>
> I don't see anything obviously problematic with that commit. (The
> #phy-cells property added is wrong as ethernet phys don't use the phy
> binding, but that should just be ignored). I'd check if the phy probed
> and has a DT node associated with it.
>
> fw_devlink tracks parent-child dependencies and maybe changing to
> parent-grandchild affected that. We don't yet track 'phy-handle'
> dependencies, but we'd have a circular one here if we did (though that
> should be handled). Does "fw_devlink=off" help?
>
> > So, reverting that on master appears to correct the issue (together with
> > setting CONFIG_RESET_CONTROLLER=y).