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, URIBL_BLOCKED,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 A2FB5C3A589 for ; Tue, 20 Aug 2019 13:04:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 70A2422D6D for ; Tue, 20 Aug 2019 13:04:09 +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="NkPK1k5H" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729879AbfHTNEI (ORCPT ); Tue, 20 Aug 2019 09:04:08 -0400 Received: from vps0.lunn.ch ([185.16.172.187]:44896 "EHLO vps0.lunn.ch" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727006AbfHTNEI (ORCPT ); Tue, 20 Aug 2019 09:04:08 -0400 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=I7K/h5NF0hSsFkWTVB5gzSxkSpsigmltCouJ/cfBkkA=; b=NkPK1k5HnDT7h4r46UdJdzwq0q +HmBrQTNOkEQOsEV0SI+WArtAV61y4q3l5Tg/AuYDFh8k8PV9EcKKAruNd37nT0PUZBRUgT13CnTC CXe2nRoBlXay9178lQYG2ke7AKX3kwqECGqddrA74R2+gVAOZqy1PlXnn1y8ViLcXBMw=; Received: from andrew by vps0.lunn.ch with local (Exim 4.89) (envelope-from ) id 1i03nv-0005Jj-Jd; Tue, 20 Aug 2019 15:04:03 +0200 Date: Tue, 20 Aug 2019 15:04:03 +0200 From: Andrew Lunn To: Andy Duan Cc: Marco Hartmann , "davem@davemloft.net" , "netdev@vger.kernel.org" , "linux-kernel@vger.kernel.org" , Christian Herber Subject: Re: [EXT] Re: [PATCH net-next 0/1] net: fec: add C45 MDIO read/write support Message-ID: <20190820130403.GH29991@lunn.ch> References: <1566234659-7164-1-git-send-email-marco.hartmann@nxp.com> <20190819225422.GD29991@lunn.ch> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Aug 20, 2019 at 02:32:26AM +0000, Andy Duan wrote: > From: Andrew Lunn > > On Mon, Aug 19, 2019 at 05:11:14PM +0000, Marco Hartmann wrote: > > > As of yet, the Fast Ethernet Controller (FEC) driver only supports > > > Clause 22 conform MDIO transactions. IEEE 802.3ae Clause 45 defines a > > > modified MDIO protocol that uses a two staged access model in order to > > > increase the address space. > > > > > > This patch adds support for Clause 45 conform MDIO read and write > > > operations to the FEC driver. > > > > Hi Marco > > > > Do all versions of the FEC hardware support C45? Or do we need to make use > > of the quirk support in this driver to just enable it for some revisions of FEC? > > > > Thanks > > Andrew > > i.MX legacy platforms like i.MX6/7 series, they doesn't support Write & Read Increment. > But for i.MX8MQ/MM series, it support C45 full features like Write & Read Increment. > > For the patch itself, it doesn't support Write & Read Increment, so I think the patch doesn't > need to add quirk support. Hi Andy So what happens with something older than a i.MX8MQ/MM when a C45 transfer is attempted? This patch adds a new write. Does that write immediately trigger a completion interrupt? Does it never trigger an interrupt, and we have to wait FEC_MII_TIMEOUT? Ideally, if the hardware does not support C45, we want it to return EOPNOTSUPP. Thanks Andrew