Re: [PATCH net-next v1 2/4] net: phy: micrel: lan8841: set default PTP latency values
From: Oleksij Rempel
Date: Tue Apr 23 2024 - 03:08:18 EST
Hi Richard,
On Thu, Apr 18, 2024 at 11:46:48PM -0700, Richard Cochran wrote:
> On Wed, Apr 17, 2024 at 10:23:07PM +0200, Andrew Lunn wrote:
> > I suggest you go read older messages from Richard. It was a discussion
> > with Microchip about one of their PHYs.
>
> My 2 cents:
>
> User space has all of the hooks needed to configure corrections for a
> given setup.
>
> Hard coding corrections in device drivers is bound to fail, based on
> prior experience with Vendors not knowing or caring how their products
> actually work. Vendors will publish value X one year, then delete the
> info (to avoid embarrassment), then publish the new value Y, once
> customers have forgotten about X.
>
> So, prudent users will always calibrate their beloved systems, not
> trusting the Vendors to provide anything close to reasonable.
>
> Ergo, adding new magical correction in a kernel release causes
> regressions for prudent users.
>
> But, in the end, that doesn't matter, because prudent users are used
> to being abused by well-meaning yet misguided device driver authors.
>
> Prudent users are wise, and they will re-calibrate their systems
> before rolling out an updated kernel.
Ok, i see. Thank you for your feedback.
Are the recommended FOSS projects managing calibration values per-
linkmode/port/device in user space?
What is recommended way for calibration? Using some recommended device?
Regards,
Oleksij
--
Pengutronix e.K. | |
Steuerwalder Str. 21 | http://www.pengutronix.de/ |
31137 Hildesheim, Germany | Phone: +49-5121-206917-0 |
Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |