From mboxrd@z Thu Jan 1 00:00:00 1970 From: Florian Fainelli Subject: Re: [PATCH RFC 13/26] sfp: add phylink based SFP module support Date: Thu, 07 Jan 2016 12:23:53 -0800 Message-ID: <568EC959.1080706@gmail.com> References: <20151207173553.GU8644@n2100.arm.linux.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org To: Russell King , Thomas Petazzoni Return-path: Received: from mail-pa0-f42.google.com ([209.85.220.42]:33727 "EHLO mail-pa0-f42.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752230AbcAGUY1 (ORCPT ); Thu, 7 Jan 2016 15:24:27 -0500 Received: by mail-pa0-f42.google.com with SMTP id cy9so266901595pac.0 for ; Thu, 07 Jan 2016 12:24:27 -0800 (PST) In-Reply-To: Sender: netdev-owner@vger.kernel.org List-ID: On 07/12/15 09:38, Russell King wrote: > Add support for SFP hotpluggable modules via phylink. This supports > both copper and optical SFP modules, which require different Serdes > modes in order to properly negotiate the link. > > Optical SFP modules typically require the Serdes link to be talking > 1000base-X mode - this is the gigabit ethernet mode defined by the > 802.3 standard. > > Copper SFP modules typically integrate a PHY in the module to convert > from Serdes to copper, and the PHY will be configured by the vendor > to either present a 1000base-X Serdes link (for fixed 1000base-T) or > a SGMII Serdes link. However, this is vendor defined, so we instead > detect the PHY, switch the link to SGMII mode, and use traditional > PHY based negotiation. This goes pretty deep into the SFP specs, which I don't have a fresh memory of, few nits here and there: include/linux/sfp.h contains things that could be useful for user-space since these are standard definitions, should this be moved to uapi such that ethtool could use that header too? -- Florian