Re: [PATCH net-next 11/14] net: pse-pd: Add support for PSE device index

[Oleksij Rempel]

On Tue, Jan 07, 2025 at 05:18:34PM -0800, Jakub Kicinski wrote:
> On Sat, 04 Jan 2025 23:27:36 +0100 Kory Maincent wrote:
> > From: Kory Maincent (Dent Project) <kory.maincent@xxxxxxxxxxx>
> > 
> > Add support for a PSE device index to report the PSE controller index to
> > the user through ethtool. This will be useful for future support of power
> > domains and port priority management.
> 
> Can you say more? How do the PSE controllers relate to netdevs?
> ethtool is primarily driven by netdev / ifindex.
> If you're starting to build your own object hierarchy you may be
> better off with a separate genl family.
            
I hope this schema may help to explain the topology:

	                              +--- netdev / ifindex 0
	    +--- PSE power domain 0 --+--- netdev / ifindex 1
            |                         +--- netdev / ifindex 2
PSE ctrl 0 -+
            |                         +--- netdev / ifindex 3
            +--- PSE power domain 1 --+--- netdev / ifindex 4
	                              +--- netdev / ifindex 5

	                              +--- netdev / ifindex 6
	    +--- PSE power domain 2 --+--- netdev / ifindex 7
            |                         +--- netdev / ifindex 8
PSE ctrl 1 -+
            |                         +--- netdev / ifindex 9
            +--- PSE power domain 3 --+--- netdev / ifindex 10
	                              +--- netdev / ifindex 11

PSE device index is needed to find actually PSE controller related to
specific netdev / ifindex.

Regards,
Oleksij
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