Re: [PATCH net v2 2/2] net: dsa: b53: restore the NSP IMP port 2 Gbps mode
From: Andrew Lunn
Date: Mon Oct 26 2026 - 16:34:28 EST
On Mon, Oct 26, 2026 at 12:34:05PM -0700, Florian Fainelli wrote:
> 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?
Yes, it can be done sometime in the future.
Andrew