Re: [PATCH RFC V1 net-next 3/4] net: Let the active time stamping layer be selectable.

From: Grygorii Strashko
Date: Wed Apr 06 2022 - 09:48:44 EST




On 05/04/2022 18:48, Richard Cochran wrote:
On Tue, Apr 05, 2022 at 03:29:05PM +0200, Andrew Lunn wrote:

Maybe. Device tree is supposed to describe the hardware, not how you
configure the hardware. Which PTP you using is a configuration choice,
so i expect some people will argue it should not be in DT.

+1

Pure DT means no configuration choices.

(but you find many examples that break the rules!)


My point was related to one of issues described by Michael Walle in this thread:
- supporting TS by the PHY may require also additional board support;
- phy_has_hwtstamp() defined statically by PHY drivers without taking into account board design;
- Kconfig option Doesn't really work with generic distro support and not allowed per-port cfg.

So adding smth like "hwtstamp-en" will clear identify that this particular PHY on this particular board
supports time stamping.
(or hwtstamp-full/hwtstamp-rx/hwtstamp-tx).

Of course, it will not help with default or dynamic selection of time stamping layer :(,
but it will be one problem less.

--
Best regards,
Grygorii, Ukraine