Re: [PATCH net-next] net: ethtool: allow MAC drivers to override ethtool get_ts_info

On Wed, Jan 20, 2021 at 08:04:51PM -0800, Richard Cochran wrote:

On Thu, Jan 14, 2021 at 10:38:00PM +0000, Russell King - ARM Linux admin wrote:

quoted

So, I think the only way to prevent a regression with the code as
it is today is that we _never_ support PTP on Marvell PHYs - because
doing so _will_ break the existing MVPP2 driver's implementation and
cause a regression.

The situation isn't as bad as it seems.

For one thing, mvpp2 incorrectly selects NETWORK_PHY_TIMESTAMPING.
It really shouldn't.  I'm submitting a fix soon.

As long as the new PHY driver (or at least the PTP bit) depends on
NETWORK_PHY_TIMESTAMPING, then that allows users who _really_ want
that to enable the option at compile time.  This option adds extra
checks into the networking hot path, and almost everyone should avoid
enabling it.

As I already explained to you, you can *NOT* use kernel configuration
to make the choice.  ARM is a multi-platform kernel, and we will not
stand for platform choices dictated by kernel configuration options.

-- 
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
FTTP is here! 40Mbps down 10Mbps up. Decent connectivity at last!