From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D9ED0C2D0A3 for ; Mon, 2 Nov 2020 02:43:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 91F4D221FF for ; Mon, 2 Nov 2020 02:43:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727701AbgKBCni (ORCPT ); Sun, 1 Nov 2020 21:43:38 -0500 Received: from mga04.intel.com ([192.55.52.120]:51322 "EHLO mga04.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727450AbgKBCni (ORCPT ); Sun, 1 Nov 2020 21:43:38 -0500 IronPort-SDR: bYx3XcfmK0ZNstbAk5hL2ukxJxHGGu/jUeGns9VBHceeZowr3D97XsFgO65Z/vjUJm63qhouPW uFW/Qi5ySrAA== X-IronPort-AV: E=McAfee;i="6000,8403,9792"; a="166236334" X-IronPort-AV: E=Sophos;i="5.77,443,1596524400"; d="scan'208";a="166236334" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga006.fm.intel.com ([10.253.24.20]) by fmsmga104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 01 Nov 2020 18:43:38 -0800 IronPort-SDR: ULPce4o1gTVqveAMyWhF84RLXE1LKUTUd9JBJfaPvsKciCjS4GlK1I6inejs+27DXk/Jqow3nA PGiJZ4EhiD6A== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.77,443,1596524400"; d="scan'208";a="526535655" Received: from yilunxu-optiplex-7050.sh.intel.com (HELO localhost) ([10.239.159.141]) by fmsmga006.fm.intel.com with ESMTP; 01 Nov 2020 18:43:35 -0800 Date: Mon, 2 Nov 2020 10:38:09 +0800 From: Xu Yilun To: Andrew Lunn Cc: jesse.brandeburg@intel.com, anthony.l.nguyen@intel.com, davem@davemloft.net, kuba@kernel.org, mdf@kernel.org, lee.jones@linaro.org, linux-kernel@vger.kernel.org, linux-fpga@vger.kernel.org, netdev@vger.kernel.org, trix@redhat.com, lgoncalv@redhat.com, hao.wu@intel.com, yilun.xu@intel.com Subject: Re: [RFC PATCH 1/6] docs: networking: add the document for DFL Ether Group driver Message-ID: <20201102023809.GA10673@yilunxu-OptiPlex-7050> References: <1603442745-13085-1-git-send-email-yilun.xu@intel.com> <1603442745-13085-2-git-send-email-yilun.xu@intel.com> <20201023153731.GC718124@lunn.ch> <20201026085246.GC25281@yilunxu-OptiPlex-7050> <20201026130001.GC836546@lunn.ch> <20201026173803.GA10743@yilunxu-OptiPlex-7050> <20201026191400.GO752111@lunn.ch> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201026191400.GO752111@lunn.ch> User-Agent: Mutt/1.5.24 (2015-08-30) Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Hi Andrew: On Mon, Oct 26, 2020 at 08:14:00PM +0100, Andrew Lunn wrote: > > > > > Do you really mean PHY? I actually expect it is PCS? > > > > > > > > For this implementation, yes. > > > > > > Yes, you have a PHY? Or Yes, it is PCS? > > > > Sorry, I mean I have a PHY. > > > > > > > > To me, the phylib maintainer, having a PHY means you have a base-T > > > interface, 25Gbase-T, 40Gbase-T? That would be an odd and expensive > > > architecture when you should be able to just connect SERDES interfaces > > > together. > > You really have 25Gbase-T, 40Gbase-T? Between the FPGA & XL710? > What copper PHYs are using? > > > I see your concerns about the SERDES interface between FPGA & XL710. > > I have no concerns about direct SERDES connections. That is the normal > way of doing this. It keeps it a lot simpler, since you don't have to > worry about driving the PHYs. > I did some investigation and now I have some details. The term 'PHY' described in Ether Group Spec should be the PCS + PMA, a figure below for one configuration: +------------------------+ +-----------------+ | Host Side Ether Group | | XL710 | | | | | | +--------------------+ | | | | | 40G Ether IP | | | | | | | | | | | | +---------+ | | XLAUI | | | | MAC - |PCS - PMA| | |----------| PMA - PCS - MAC | | | +---------+ | | | | +-+--------------------+-+ +-----------------+ Thanks, Yilun