Re: [PATCH net v2 2/2] net: dsa: b53: restore the NSP IMP port 2 Gbps mode

[Florian Fainelli]

On 10/26/26 12:11, Andrew Lunn wrote:
> On Mon, Oct 26, 2026 at 11:34:36AM -0700, Florian Fainelli wrote:
> > On 10/26/26 11:31, Jonas Gorski wrote:
> > > Hi,
> > >
> > > On Thu, Oct 22, 2026 at 11:11 PM Florian Fainelli
> > > <florian.fainelli@xxxxxxxxxxxx> wrote:
> > > > The Northstar Plus IMP port uses the switch's proprietary 2 Gbps mode for
> > > > its internal link to the AMAC.  Its fixed-link description reports 1 Gbps,
> > > > so applying that speed clears PORT_OVERRIDE_SPEED_2000M and leaves the two
> > > > ends of the internal link configured at different speeds.
> > >
> > > Sounds like the devicetrees are wrong. Shouldn't that fixed-link
> > > description be updated to be 2 Gbps then? ;p
> >
> > That's a fair ask, however that would require introducing 2Gbits/sec all
> > over the place, and it's not like we really have a good way to report that
> > even through emulated PHY registers. This would not be a bug fix however,
> > which this patch set is targeting.
>
> Hi Florian
>
> As far as i know phylink fixed-link does not care what the speed is,
> and it does not try to emulate it in the PHY. So it probably just
> works. Assuming the DSA driver is using phylink.

Can we agree this is outside of the scope of what is being fixed here?

Without updates to Device Tree binding, swphy, phylink and the drivers 
that do depend upon supporting SPEED_2000, that speed is going to be 
rejected or not acted on at various layers in the stack.
--
Florian