From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754788AbcKUPnt convert rfc822-to-8bit (ORCPT ); Mon, 21 Nov 2016 10:43:49 -0500 Received: from bastet.se.axis.com ([195.60.68.11]:41772 "EHLO bastet.se.axis.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753534AbcKUPnr (ORCPT ); Mon, 21 Nov 2016 10:43:47 -0500 From: Lars Persson To: Joao Pinto CC: Giuseppe CAVALLARO , Rayagond Kokatanur , Rabin Vincent , mued dib , David Miller , Jeff Kirsher , "jiri@mellanox.com" , "saeedm@mellanox.com" , "idosch@mellanox.com" , netdev , "linux-kernel@vger.kernel.org" , "CARLOS.PALMINHA@synopsys.com" , =?iso-8859-1?Q?Andreas_Irest=E5l?= , "alexandre.torgue@st.com" , "linux-arm-kernel@lists.infradead.org" Subject: Re: Synopsys Ethernet QoS Driver Thread-Topic: Synopsys Ethernet QoS Driver Thread-Index: AQHSQmzN/OGoygWHGUOcmjf+1thtfKDi2ueAgAB2QICAAAWHAIAAGsuH////PACAAAtSgIAAGzIM Date: Mon, 21 Nov 2016 15:43:43 +0000 Message-ID: References: <1dbb6047-2bbb-4d56-2a62-ab65a0254844@synopsys.com> <20161119135654.GA14079@lnxartpec.se.axis.com> <1248f4ce-4859-10e6-fef9-342ea543f8d4@synopsys.com> <87c8a24b-0812-7850-cb3f-7be691bab432@st.com> , In-Reply-To: Accept-Language: en-US Content-Language: sv-SE X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-exchange-transport-fromentityheader: Hosted Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 8BIT MIME-Version: 1.0 X-TM-AS-GCONF: 00 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > 21 nov. 2016 kl. 16:06 skrev Joao Pinto : > >> On 21-11-2016 14:25, Giuseppe CAVALLARO wrote: >>> On 11/21/2016 2:28 PM, Lars Persson wrote: >>> >>> >>>> 21 nov. 2016 kl. 13:53 skrev Giuseppe CAVALLARO : >>>> >>>> Hello Joao >>>> >>>>> On 11/21/2016 1:32 PM, Joao Pinto wrote: >>>>> Hello, >>>>> >>>>>>> On 21-11-2016 05:29, Rayagond Kokatanur wrote: >>>>>>>> On Sat, Nov 19, 2016 at 7:26 PM, Rabin Vincent wrote: >>>>>>>> On Fri, Nov 18, 2016 at 02:20:27PM +0000, Joao Pinto wrote: >>>>>>>> For now we are interesting in improving the synopsys QoS driver under >>>>>>>> /nect/ethernet/synopsys. For now the driver structure consists of a >>>>>>>> single file >>>>>>>> called dwc_eth_qos.c, containing synopsys ethernet qos common ops and >>>>>>>> platform >>>>>>>> related stuff. >>>>>>>> >>>>>>>> Our strategy would be: >>>>>>>> >>>>>>>> a) Implement a platform glue driver (dwc_eth_qos_pltfm.c) >>>>>>>> b) Implement a pci glue driver (dwc_eth_qos_pci.c) >>>>>>>> c) Implement a "core driver" (dwc_eth_qos.c) that would only have >>>>>>>> Ethernet QoS >>>>>>>> related stuff to be reused by the platform / pci drivers >>>>>>>> d) Add a set of features to the "core driver" that we have available >>>>>>>> internally >>>>>>> >>>>>>> Note that there are actually two drivers in mainline for this hardware: >>>>>>> >>>>>>> drivers/net/ethernet/synopsis/ >>>>>>> drivers/net/ethernet/stmicro/stmmac/ >>>>>> >>>>>> Yes the later driver (drivers/net/ethernet/stmicro/stmmac/) supports >>>>>> both 3.x and 4.x. It has glue layer for pci, platform, core etc, >>>>>> please refer this driver once before you start. >>>>>> >>>>>> You can start adding missing feature of 4.x in stmmac driver. >>>>> >>>>> Thanks you all for all the info. >>>>> Well, I think we are in a good position to organize the ethernet drivers >>>>> concerning Synopsys IPs. >>>>> >>>>> First of all, in my opinion, it does not make sense to have a ethernet/synopsis >>>>> (typo :)) when ethernet/stmicro is also for a synopsys IP. If we have another >>>>> vendor using the same IP it should be able to reuse the commonn operations. But >>>>> I would put that discussion for later :) >>>>> >>>>> For now I suggest that for we create ethernet/qos and create there a folder >>>>> called dwc (designware controller) where all the synopsys qos IP specific code >>>>> in order to be reused for example by ethernet/stmicro/stmmac/. We just have to >>>>> figure out a clean interface for "client drivers" like stmmac to interact with >>>>> the new qos driver. >>>>> >>>>> What do you think about this approach? >>>> >>>> The stmmac drivers run since many years on several platforms >>>> (sh4, stm32, arm, x86, mips ...) and it supports an huge of amount of >>>> configurations starting from 3.1x to 3.7x databooks. >>>> >>>> It also supports QoS hardware; for example, 4.00a, 4.10a and 4.20a >>>> are fully working. >>>> >>>> Also the stmmac has platform, device-tree and pcie supports and >>>> a lot of maintained glue-logic files. >>>> >>>> It is fully documented inside the kernel tree. >>>> >>>> I am happy to have new enhancements from other developers. >>>> So, on my side, if you want to spend your time on improving it on your >>>> platforms please feel free to do it! >>>> >>>> Concerning the stmicro/stmmac naming, these come from a really old >>>> story and have no issue to adopt new folder/file names. >>>> >>>> I am also open to merge fixes and changes from ethernet/synopsis. >>>> I want to point you on some benchmarks made by Alex some months ago >>>> (IIRC) that showed an stmmac winner (due to the several optimizations >>>> analyzed and reviewed in this mailing list). >>>> >>>> Peppe >>>> >>> >>> Hello Joao and others, >>> > > Hi Lars, > >>> As the maintainer of dwc_eth_qos.c I prefer also that we put efforts on the >>> most mature driver, the stmmac. >>> >>> I hope that the code can migrate into an ethernet/synopsys folder to keep the >>> convention of naming the folder after the vendor. This makes it easy for >>> others to find the driver. >>> >>> The dwc_eth_qos.c will eventually be removed and its DT binding interface can >>> then be implemented in the stmmac driver. > > So your ideia is to pick the ethernet/stmmac and rename it to ethernet/synopsys > and try to improve the structure and add the missing QoS features to it? Indeed this is what I prefer. > >> >> Thanks Lars, I will be happy to support all you on this transition >> and I agree on renaming all. >> >> peppe >> >> >>> - Lars >>> >>>>> >>>>> >>>>>> >>>>>>> >>>>>>> (See http://lists.openwall.net/netdev/2016/02/29/127) >>>>>>> >>>>>>> The former only supports 4.x of the hardware. >>>>>>> >>>>>>> The later supports 4.x and 3.x and already has a platform glue driver >>>>>>> with support for several platforms, a PCI glue driver, and a core driver >>>>>>> with several features not present in the former (for example: TX/RX >>>>>>> interrupt coalescing, EEE, PTP). >>>>>>> >>>>>>> Have you evaluated both drivers? Why have you decided to work on the >>>>>>> former rather than the latter? >>>>>> >>>>>> >>>>> >>>>> Thanks. >>>>> >>>>> >>>>> >>>>> >>>> >>> >> >