From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH net-next V3 5/8] net/mlx4_en: Adding support of turning off link autonegotiation via ethtool Date: Mon, 30 Jan 2017 15:25:32 -0500 (EST) Message-ID: <20170130.152532.370636093483999005.davem@davemloft.net> References: <1485708980-23468-1-git-send-email-tariqt@mellanox.com> <1485708980-23468-6-git-send-email-tariqt@mellanox.com> <063D6719AE5E284EB5DD2968C1650D6DB0273B7E@AcuExch.aculab.com> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: tariqt@mellanox.com, netdev@vger.kernel.org, eranbe@mellanox.com, lariel@mellanox.com To: David.Laight@ACULAB.COM Return-path: Received: from shards.monkeyblade.net ([184.105.139.130]:38328 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754460AbdA3U0F (ORCPT ); Mon, 30 Jan 2017 15:26:05 -0500 In-Reply-To: <063D6719AE5E284EB5DD2968C1650D6DB0273B7E@AcuExch.aculab.com> Sender: netdev-owner@vger.kernel.org List-ID: From: David Laight Date: Mon, 30 Jan 2017 14:00:28 +0000 > From: Tariq Toukan >> Sent: 29 January 2017 16:56 >> From: Ariel Levkovich >> >> 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.