From: David Laight <redacted>
Date: Mon, 30 Jan 2017 14:00:28 +0000

From: Tariq Toukan

quoted

Sent: 29 January 2017 16:56
From: Ariel Levkovich <redacted>

This feature will allow the user to disable auto negotiation
on the port for mlx4 devices while setting the speed is limited
to 1GbE speeds.
Other speeds will not be accepted in autoneg off mode.

What is the rationale behind this change?

Because it's an ethtool user feature we've had to two decades
and it allows the user greater control over the link state.

When I was writing ethernet drivers it was always better to
leave autonegotiation enabled with restricted modes than to
fix the speed.

Nothing about this change effects this.  The user is just given
the ability to turn autonegotiation off if they wish to do so.