On Wed, 2021-01-27 at 08:04 +0100, Heiner Kallweit wrote:
> On 26.01.2021 23:10, Tony Nguyen wrote:
> > From: Corinna Vinschen <vinsc...@redhat.com>
> >
> > Link speed advertising in igc has two problems:
> >
> > - When setting the advertisement via ethtool, the link speed is
> > converted
> > to the legacy 32 bit representation for the intel PHY code.
> > This inadvertently drops ETHTOOL_LINK_MODE_2500baseT_Full_BIT
> > (being
> > beyond bit 31). As a result, any call to `ethtool -s ...' drops
> > the
> > 2500Mbit/s link speed from the PHY settings. Only reloading the
> > driver
> > alleviates that problem.
> >
> > Fix this by converting the ETHTOOL_LINK_MODE_2500baseT_Full_BIT
> > to the
> > Intel PHY ADVERTISE_2500_FULL bit explicitly.
> >
> > - Rather than checking the actual PHY setting, the
> > .get_link_ksettings
> > function always fills link_modes.advertising with all link speeds
> > the device is capable of.
> >
> > Fix this by checking the PHY autoneg_advertised settings and
> > report
> > only the actually advertised speeds up to ethtool.
> >
> > Fixes: 8c5ad0dae93c ("igc: Add ethtool support")
> > Signed-off-by: Corinna Vinschen <vinsc...@redhat.com>
> > Signed-off-by: Tony Nguyen <anthony.l.ngu...@intel.com>
> > ---
> > drivers/net/ethernet/intel/igc/igc_ethtool.c | 24 +++++++++++++++-
> > ----
> > 1 file changed, 18 insertions(+), 6 deletions(-)
> >
>
> Would switching to phylib be a mid-term option for you?
> This could save quite some code and you'd get things like proper
> 2.5Gbps
> handling out of the box. Or is there anything that prevents using
> phylib?
Phylib is something we can look into though we have some device
specific quirks that we would need to see how it could be handled.
Since this is fixing a current problem and any transition to phylib
would not be immediate, I think this patch should be accepted while we
investigate phylib.
Thanks,
Tony
