Re: [PATCH net-next 2/9] ethtool: Expand Ethernet Power Equipment with PoE alongside PoDL

From: Köry Maincent
Date: Tue Nov 21 2023 - 09:56:59 EST


On Tue, 21 Nov 2023 15:19:19 +0100
Andrew Lunn <andrew@xxxxxxx> wrote:

> > > However, everything not PoDL PSE seems to be clause 33. So how about:
> > >
> > > enum ethtool_podl_pse_admin_state podl_admin_control;
> > > enum ethtool_c33_pse_admin_state c33_admin_control;
> > >
> > > At least inside the kernel we use c22, c45, c37 etc. I'm not sure they
> > > are visible to userspace, but if we don't have a better name, maybe we
> > > have to use c33 in userspace as well.
> > >
> > > I do think naming like this makes it clear we are talking about two
> > > parallel technologies, not a generic layer and then extensions for
> > > podl.
> > >
> > > What do you think?
> >
> > If we decide to add a prefix, "c33" is precise but less easily
> > understandable, why not using simply "poe" prefix?
>
> I suspect poe has the exact opposite problem, its too imprecise. Its
> too much of a marketing name, with no clear meaning. It could even be
> some people call podl poe.
>
> To some extent, this is a user space UX problem. We can be precises in
> the kernel and the kAPI. What ethtool decides to show to the user
> could be different. Although it basically is the same problem.

Alright, thanks for your answer.

> Do you have ethtool patches? What does the output look like? Oleksij
> did say a hybrid could be possible, so we probably want ethtool to
> group these properties together and make it clear what is PoDL and
> !PoDL.

No I don't, I am only using ynl for now.
I would be similar to podl:
https://kernel.googlesource.com/pub/scm/network/ethtool/ethtool/+/e6cc6807f87c74d4e5b1f1e9d21d3a74e75a258b/netlink/pse-pd.c

Duplicating the PoDL part with c33. Using the same --set-pse and --show-pse
options.

> > Maybe as POE were originally PMDI you prefer to use c33 which won't change
> > over time?
> >
> > Should I also modify the content of the enum?
> > ETHTOOL_PSE_ADMIN_STATE_* to ETHTOOL_C33_PSE_ADMIN_*
> > ETHTOOL_PSE_PW_D_STATUS_* to ETHTOOL_C33_PSE_PW_D_STATUS_*
>
> Yes. That will help avoid getting PODL and C33 properties missed up.

Alright.

Regards,
--
Köry Maincent, Bootlin
Embedded Linux and kernel engineering
https://bootlin.com