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Date: Thu, 6 Jun 2024 15:22:55 +0200
From: Andrew Lunn <andrew@lunn.ch>
To: Swathi K S <swathi.ks@samsung.com>
Cc: davem@davemloft.net, edumazet@google.com, kuba@kernel.org,
	pabeni@redhat.com, robh+dt@kernel.org,
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	'Jayati Sahu' <jayati.sahu@samsung.com>,
	Siddharth Vadapalli <s-vadapalli@ti.com>
Subject: Re: [PATCH v3 3/4] arm64: dts: fsd: Add Ethernet support for FSYS0
 Block of FSD SoC
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> > > +&ethernet_0 {
> > > +	status = "okay";
> > > +
> > > +	fixed-link {
> > > +		speed = <1000>;
> > > +		full-duplex;
> > > +	};
> > > +};
> > 
> > A fixed link on its own is pretty unusual. Normally it is combined with an
> > Ethernet switch. What is the link peer here?
> 
> It is a direct connection to the Ethernet switch managed by an external
> management unit.

Ah, interesting. This is the third example of this in about a
month. Take a look at the Realtek and TI work in this area.

So, i will ask the same questions i put to Realtek and TI. Does Linux
know about the switch in any way? Can it manage the switch, other than
SNMP, HTTP from user space? Does it know about the state of the ports,
etc?

If you say this is just a colocated management switch, which Linux is
not managing in any way, that is O.K. If you have Linux involved in
some way, please join the discussion with TI about adding a new model
for semi-autonomous switches.

   Andrew