From mboxrd@z Thu Jan 1 00:00:00 1970 From: Russell King - ARM Linux admin Subject: Re: [PATCH net-next v3 2/3] net: ethernet: mediatek: Re-add support SGMII Date: Sat, 24 Aug 2019 10:21:56 +0100 Message-ID: <20190824092156.GD13294@shell.armlinux.org.uk> References: <20190823134516.27559-1-opensource@vdorst.com> <20190823134516.27559-3-opensource@vdorst.com> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: 8bit Return-path: Content-Disposition: inline In-Reply-To: <20190823134516.27559-3-opensource@vdorst.com> Sender: netdev-owner@vger.kernel.org To: =?iso-8859-1?Q?Ren=E9?= van Dorst Cc: John Crispin , Sean Wang , Nelson Chang , "David S . Miller" , Matthias Brugger , netdev@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, linux-mips@vger.kernel.org, Frank Wunderlich , Stefan Roese List-Id: linux-mediatek@lists.infradead.org On Fri, Aug 23, 2019 at 03:45:15PM +0200, René van Dorst wrote: > + switch (state->interface) { > + case PHY_INTERFACE_MODE_SGMII: > + phylink_set(mask, 10baseT_Half); > + phylink_set(mask, 10baseT_Full); > + phylink_set(mask, 100baseT_Half); > + phylink_set(mask, 100baseT_Full); You also want 1000baseX_Full here - the connected PHY could have a fiber interface on it. > + /* fall through */ > + case PHY_INTERFACE_MODE_TRGMII: > phylink_set(mask, 1000baseT_Full); I don't know enough about this interface type to comment whether it should support 1000baseX_Full - if this is connected to a PHY that may support fiber, then it ought to set it. > + break; > + case PHY_INTERFACE_MODE_2500BASEX: > + phylink_set(mask, 2500baseX_Full); > + /* fall through */ > + case PHY_INTERFACE_MODE_1000BASEX: > + phylink_set(mask, 1000baseX_Full); Both should be set. The reasoning here is that if you have a Fiberchannel 4Gbaud SFP plugged in and connected directly to the MAC, it can operate at either 2500Base-X or 1000Base-X. If we decide to operate at 2500Base-X, then PHY_INTERFACE_MODE_2500BASEX will be chosen. Otherwise, PHY_INTERFACE_MODE_1000BASEX will be used. The user can use ethtool to control which interface mode is used by adjusting the advertise mask and/or placing the interface in manual mode and setting the speed directly. This will change the PHY_INTERFACE_MODE_xxxxBASEX (via phylink_helper_basex_speed()) between the two settings. If we lose 2500baseX_Full when 1000Base-X is selected, the user will not be able to go back to 2500Base-X mode. Yes, it's a little confusing and has slightly different rules from the other modes - partly due to phylink_helper_basex_speed(). These are the only interface modes that we dynamically switch between depending on the settings that the user configures via ethtool. -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTC broadband for 0.8mile line in suburbia: sync at 12.1Mbps down 622kbps up According to speedtest.net: 11.9Mbps down 500kbps up