Re: [RFC PATCH v4 2/4] dpll: Add DPLL framework base functions

Jiri Pirko
2022-12-07T13:10:49Z

Tue, Dec 06, 2022 at 06:27:05PM CET, kuba@kernel.org wrote:
>On Tue, 6 Dec 2022 09:50:19 +0100 Jiri Pirko wrote:
>>> Yeah, that's a slightly tricky one. We'd probably need some form
>>> of second order association. Easiest if we link it to a devlink
>>> instance, I reckon. The OCP clock card does not have netdevs so we
>>> can't follow the namespace of netdevs (which would be the second
>>> option).
>>
>> Why do we need this association at all?
>
>Someone someday may want netns delegation and if we don't have the
>support from the start we may break backward compat introducing it.

Hmm. Can you imagine a usecase?

Link to devlink instance btw might be a problem. In case of mlx5, one
dpll instance is going to be created for 2 (or more) PFs. 1 per ConnectX
ASIC as there is only 1 clock there. And PF devlinks can come and go,
does not make sense to link it to any of them.

Thinking about it a bit more, DPLL itself has no network notion. The
special case is SyncE pin, which is linked to netdevice. Just a small
part of dpll device. And the netdevice already has notion of netns.
Isn't that enough?