Hi Russell,

On 27/11/2025 19:04, Russell King (Oracle) wrote:

On Thu, Nov 27, 2025 at 06:17:46PM +0100, Maxime Chevallier wrote:

quoted

Ethernet provides a wide variety of layer 1 protocols and standards for
data transmission. The front-facing ports of an interface have their own
complexity and configurability.

Introduce a representation of these front-facing ports. The current code
is minimalistic and only support ports controlled by PHY devices, but
the plan is to extend that to SFP as well as raw Ethernet MACs that
don't use PHY devices.

This minimal port representation allows describing the media and number
of pairs of a BaseT port. From that information, we can derive the
linkmodes usable on the port, which can be used to limit the
capabilities of an interface.

For now, the port pairs and medium is derived from devicetree, defined
by the PHY driver, or populated with default values (as we assume that
all PHYs expose at least one port).

The typical example is 100M ethernet. 100BaseT can work using only 2
pairs on a Cat 5 cables.

Correction: 100BASE-TX. 100BASE-T, which covers the family of 100BASE-T
media, includes 100BASE-T4 which is over all four pairs of the cable.

 As Rob's bot made what appears at a first glance to be incorrect
comments, I'm not sure a resend is on the table yet. Do you want me to
send a v21 with the updated description ? I have the same question about
your comment on patch 2 :)

I'll gladly resend, but that'll be after the 24h cooldown.

Thanks a lot for taking a look a this,

Maxime