Re: [PATCH v3 3/5] net: Let the active time stamping layer be selectable.

From: Köry Maincent
Date: Fri Mar 10 2023 - 05:49:14 EST


Hello Vladimir,

On Thu, 9 Mar 2023 01:03:21 +0200
Vladimir Oltean <vladimir.oltean@xxxxxxx> wrote:

> (trimmed CC list of bouncing email addresses)

Thanks, I will be more careful on next patch series version.

> From previous discussions, I believe that a device tree property was
> added in order to prevent perceived performance regressions when
> timestamping support is added to a PHY driver, correct?

Yes, i.e. to select the default and better timestamp on a board.

> I have a dumb question: if updating the device trees is needed in order
> to prevent these behavior changes, then how is the regression problem
> addressed for those device trees which don't contain this new property
> (all device trees)?

On that case there is not really solution, but be aware that
CONFIG_PHY_TIMESTAMPING need to be activated to allow timestamping on the PHY.
Currently in mainline only few (3) defconfig have it enabled so it is really
not spread, maybe I could add more documentation to prevent further regression
issue when adding support of timestamp to a PHY driver.

Regards,
Köry