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=-2.0 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, 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 69C1EC00454 for ; Mon, 9 Dec 2019 13:43:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 03A462073D for ; Mon, 9 Dec 2019 13:43:41 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=lunn.ch header.i=@lunn.ch header.b="VqGpcks2" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727756AbfLINnk (ORCPT ); Mon, 9 Dec 2019 08:43:40 -0500 Received: from vps0.lunn.ch ([185.16.172.187]:42106 "EHLO vps0.lunn.ch" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726687AbfLINnj (ORCPT ); Mon, 9 Dec 2019 08:43:39 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lunn.ch; s=20171124; h=In-Reply-To:Content-Type:MIME-Version:References:Message-ID: Subject:Cc:To:From:Date:Sender:Reply-To:Content-Transfer-Encoding:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Id:List-Help:List-Unsubscribe:List-Subscribe: List-Post:List-Owner:List-Archive; bh=pk0KyT5G1CnUyogiQaj5MmGP9BYTp+qHde9CkGvk/qM=; b=VqGpcks2P2oOh3/URMEKxJpz6f kQwdrTmJxPeUF8qe33lCRhuNflyH4pLpXARxFPobr3Y9BJVMgp0ia8gkzm0KstDxm8fE9Vxl+WaJw +gUqWD8OWNM0cMd12m2/AklKb86tqK1G2jH+yTMOwRuuwJyZwRCT2DlPtGdMIr3Ju3AI=; Received: from andrew by vps0.lunn.ch with local (Exim 4.92.2) (envelope-from ) id 1ieJK4-0005Pi-Tb; Mon, 09 Dec 2019 14:43:36 +0100 Date: Mon, 9 Dec 2019 14:43:36 +0100 From: Andrew Lunn To: =?iso-8859-1?Q?J=FCrgen?= Lambrecht Cc: "netdev@vger.kernel.org" , rasmus.villemoes@prevas.dk, Thomas Petazzoni , vivien.didelot@gmail.com, Antoine =?iso-8859-1?Q?T=E9nart?= Subject: Re: net: dsa: mv88e6xxx: error parsing ethernet node from dts Message-ID: <20191209134336.GC9099@lunn.ch> References: <27f65072-f3a1-7a3c-5e9e-0cc86d25ab51@televic.com> <20191204153804.GD21904@lunn.ch> <20191204171336.GF21904@lunn.ch> <5851b137-2a3f-f8b3-cd0a-6efc2b7df67d@televic.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <5851b137-2a3f-f8b3-cd0a-6efc2b7df67d@televic.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org > A strange thing to me however is why - in my dts and in > vf610-zii-ssmb-spu3.dts - there is 2 times a 'fixed-link' > declaration? Moreover, when I omit the first declaration, the kernel > crashes (oops). The FEC driver expect there to be a PHY connected to the MAC, and the PHY should indicate what speed the link is running at. However, the FEC is directly connected to the switch, there is no PHY involved. To keep the FEC happy, and to tell it what speed to use, a fixed-link PHY is used. It uses the same API as a real PHY, and indicates the link is using the speed as defined in DT. So the FEC runs at 100Mbps. The DSA driver defaults to configuring the CPU port at its maximum speed. For this chip, that is 1Gbps. However, the Vybrid FEC can only support 100Mbps. So we need to force the CPU port to the slower speed. Hence the fixed link in the CPU node. Andrew