Re: [PATCH] ARM: dts: imx6dl: SolidRun: add phy node with 100Mb/s max-speed

[Russell King - ARM Linux admin]

On Sun, Sep 15, 2019 at 04:42:52PM +0200, Andrew Lunn wrote:
> > > OF: fdt: Machine model: SolidRun HummingBoard Solo/DualLite
> > > ...
> > > # ethtool eth0
> > > Settings for eth0:
> > >         Supported ports: [ TP MII ]
> > >         Supported link modes:   10baseT/Half 10baseT/Full
> > >                                 100baseT/Half 100baseT/Full
> > >                                 1000baseT/Full
> > >         Supported pause frame use: Symmetric
> > >         Supports auto-negotiation: Yes
> > >         Supported FEC modes: Not reported
> > >         Advertised link modes:  10baseT/Half 10baseT/Full
> > >                                 100baseT/Half 100baseT/Full
> > >                                 1000baseT/Full
> > >         Advertised pause frame use: Symmetric
> > >         Advertised auto-negotiation: Yes
> > >         Advertised FEC modes: Not reported
> > >         Link partner advertised link modes:  10baseT/Half 10baseT/Full
> > >                                              100baseT/Half 100baseT/Full
> > >                                              1000baseT/Full
> > >         Link partner advertised pause frame use: Symmetric
> > >         Link partner advertised auto-negotiation: Yes
> > >         Link partner advertised FEC modes: Not reported
> > >         Speed: 1000Mb/s
> > >         Duplex: Full
> > >         Port: MII
> > >         PHYAD: 0
> > >         Transceiver: internal
> > >         Auto-negotiation: on
> > >         Supports Wake-on: d
> > >         Wake-on: d
> > >         Link detected: yes
> 
> > Note that the FEC does *not* support 1000baseT/Half.
> 
> Hi Russell
> 
> fec_main.c has code to mask it out. And it is not listed in the modes
> you have above. So as you say, this all looks to be working.
> 
> I'm wondering if there is an older variant of the hardware with
> 100Mbps magnetics, and the boot loader is setting something in the
> PHY? It could be we are now stomping over that?

Not according to Rabeeh, the SolidRun CTO:

< rabeeh> all i.MX6 based machines from SolidRun are 1Gbps phys
< rabeeh> i thought that we fixed that information, documentation wise;
          but seems not

Even the Carrier1 board that pre-dates Hummingboards had the AR8035
with 1G magnetics.

The schematics I have for the Cubox-i state that the RJ45 jack (which
contains the magnetics) is to be "Gigabit".

There was a 10/100M option for the microsom, which is selected by where
a resistor pack is fitted, having the effect of configuring the AR8035
differently.  I seem to recall the 10/100M option in the early days was
to use a different Atheros PHY.

However, I'm not aware of 10/100M option making it into production, and
Rabeeh's comment (who was involved in the design) confirms that.

-- 
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