From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alexandre Belloni Subject: Re: [PATCH net-next 4/6] arm64: dts: fsl: ls1028a: Add Felix switch port DT node Date: Mon, 24 Jun 2019 20:26:14 +0200 Message-ID: <20190624182614.GC5690@piout.net> References: <1561131532-14860-1-git-send-email-claudiu.manoil@nxp.com> <1561131532-14860-5-git-send-email-claudiu.manoil@nxp.com> <20190621164940.GL31306@lunn.ch> <20190624115558.GA5690@piout.net> <20190624142625.GR31306@lunn.ch> <20190624152344.3bv46jjhhygo6zwl@lx-anielsen.microsemi.net> <20190624162431.GX31306@lunn.ch> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20190624162431.GX31306@lunn.ch> Sender: linux-kernel-owner@vger.kernel.org To: Andrew Lunn Cc: "Allan W. Nielsen" , Claudiu Manoil , "David S . Miller" , "devicetree@vger.kernel.org" , "netdev@vger.kernel.org" , Alexandru Marginean , "linux-kernel@vger.kernel.org" , "UNGLinuxDriver@microchip.com" , Allan Nielsen , Rob Herring , "linux-arm-kernel@lists.infradead.org" List-Id: devicetree@vger.kernel.org On 24/06/2019 18:24:31+0200, Andrew Lunn wrote: > On Mon, Jun 24, 2019 at 05:23:45PM +0200, Allan W. Nielsen wrote: > > Hi Andrew, > > > > The 06/24/2019 16:26, Andrew Lunn wrote: > > > > > Yeah, there are 2 ethernet controller ports (managed by the enetc driver) > > > > > connected inside the SoC via SGMII links to 2 of the switch ports, one of > > > > > these switch ports can be configured as CPU port (with follow-up patches). > > > > > > > > > > This configuration may look prettier on DSA, but the main restriction here > > > > > is that the entire functionality is provided by the ocelot driver which is a > > > > > switchdev driver. I don't think it would be a good idea to copy-paste code > > > > > from ocelot to a separate dsa driver. > > > > > > > > > > > > > We should probably make the ocelot driver a DSA driver then... > > > An important part of DSA is being able to direct frames out specific > > > ports when they ingress via the CPU port. Does the silicon support > > > this? At the moment, i think it is using polled IO. > > > > That is supported, it requires a bit of initial configuration of the Chip, but > > nothing big (I believe this configuration is part of Claudiu's change-set). > > > > But how do you envision this done? > > > > - Let the existing SwitchDev driver and the DSA driver use a set of common > > functions. > > - Convert the existing Ocelot driver from SwitchDev to DSA > > - Fork (copy) the existing driver of Ocelot, and modify it as needed for the > > Felix driver > > > > My guess is the first one, but I would like to understand what you have in mind. > > I don't know the various architectures the switch is used in. But it > does seem like a core library, and then a switchdev wrapper for Ocelot > and a DSA wrapper for Felix would make sense. Ocelot could also be used in a DSA setting where one port can be connected to an external MAC and be used to inject/extract frames to/from any other ports. In that case, the IFH would serve as the DSA tag. -- Alexandre Belloni, Bootlin Embedded Linux and Kernel engineering https://bootlin.com