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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id DCEA9C433EF for ; Tue, 8 Feb 2022 15:53:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1345162AbiBHPxR (ORCPT ); Tue, 8 Feb 2022 10:53:17 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34684 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235311AbiBHPxO (ORCPT ); Tue, 8 Feb 2022 10:53:14 -0500 Received: from mail-pl1-x62f.google.com (mail-pl1-x62f.google.com [IPv6:2607:f8b0:4864:20::62f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9B337C061576; Tue, 8 Feb 2022 07:53:13 -0800 (PST) Received: by mail-pl1-x62f.google.com with SMTP id x3so14175733pll.3; Tue, 08 Feb 2022 07:53:13 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:content-transfer-encoding:in-reply-to :user-agent; bh=gAm+PLZtrqdu/2KKj3BZozQaVMMACzxvjpkrHL/obM4=; b=aV/EE1edQCucPEr+plYfTdxaMVX8QN1x4M6sMVj9wVDOxMMG+25UrgT8O96rKHY80V KBwM8FJcupa7PIPHI0rXalxH1N6c1tXZ2Vd26NRBL3UwSSKBaL8OkLisb1sTnoh0Zhw7 qPOuUGusze8e6ezam8tunqmF5M2RO+K084dzHN2iJlPlCim04ptuRsL+nSJiZhq95Hzn Vu2qD8CxGOp8VB1vuNdcMvZSkxKBKhhshz7MDCNKiirIp1+dJv2tUSTYk1KQNEeyKLCO LKeR4zhbVfCs70dJkup1PcdC+4vKseKVk0eFTPeuOEAkLttLeTvfHAU2Vnx3qZZVbuSQ MzSA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:content-transfer-encoding :in-reply-to:user-agent; bh=gAm+PLZtrqdu/2KKj3BZozQaVMMACzxvjpkrHL/obM4=; b=pgpTs1MwsnzhgGJ1xEVasS+gNE5wV0FrVSj3d/p0wU3Qwaix2PRGPdqL5kLesRyF2S kWPG+S1mZjcZmvLTvDekW/9jA2r4P43rSOA1tVHqZyKi4tW9EDL3CdmK1QoQ3lxH+iOh le9kTAZFAPM6L0NPgHk9R5J5x6EQyIpbjVeEylA08F0jU3DxfmCER4dMaq0IozVjXS9d 71c7yoTkno76HPWjg8YwmIbTeJjQiTkDfgQh3MZAwlVxXxLETfA1pBS8HTFEixlrnCiM ZYQUrsER/tGpOILyCoA9GpICSnDANw2RFbQOjeq+u+8ZNrJdKfr1uA2uIzPuSR0Lhxab aDmQ== X-Gm-Message-State: AOAM531G0mD6VWn1n54byP2m+QCqehIFqr3Mrr0jTjypjkxp/zzMbz+h 8WZKszpckL0PL8N/9zitZ9g= X-Google-Smtp-Source: ABdhPJybJREJFmQkPKtB0rsnZk0tzZgG7w0ZBF+GSQrj0s3mvdMvi7ThmDAG3834IOzuqFRMQOvYLg== X-Received: by 2002:a17:903:2286:: with SMTP id b6mr5280223plh.94.1644335593021; Tue, 08 Feb 2022 07:53:13 -0800 (PST) Received: from localhost ([2405:201:2003:b021:6001:8ce1:3e29:705e]) by smtp.gmail.com with ESMTPSA id o21sm17116826pfu.100.2022.02.08.07.53.09 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Tue, 08 Feb 2022 07:53:12 -0800 (PST) Date: Tue, 8 Feb 2022 21:23:06 +0530 From: Raag Jadav To: "Russell King (Oracle)" Cc: Andrew Lunn , Heiner Kallweit , "David S. Miller" , Jakub Kicinski , Steen Hegelund , Bjarni Jonasson , netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] net: phy: mscc: enable MAC SerDes autonegotiation Message-ID: <20220208155306.GA3003@localhost> References: <1644043492-31307-1-git-send-email-raagjadav@gmail.com> <20220206171234.GA5778@localhost> <20220207174948.GA5183@localhost> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: User-Agent: Mutt/1.5.24 (2015-08-30) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Feb 08, 2022 at 09:45:13AM +0000, Russell King (Oracle) wrote: > On Mon, Feb 07, 2022 at 11:19:48PM +0530, Raag Jadav wrote: > > On Sun, Feb 06, 2022 at 07:01:41PM +0100, Andrew Lunn wrote: > > > On Sun, Feb 06, 2022 at 10:42:34PM +0530, Raag Jadav wrote: > > > > On Sat, Feb 05, 2022 at 03:57:49PM +0100, Andrew Lunn wrote: > > > > > On Sat, Feb 05, 2022 at 12:14:52PM +0530, Raag Jadav wrote: > > > > > > Enable MAC SerDes autonegotiation to distinguish between > > > > > > 1000BASE-X, SGMII and QSGMII MAC. > > > > > > > > > > How does autoneg help you here? It just tells you about duplex, pause > > > > > etc. It does not indicate 1000BaseX, SGMII etc. The PHY should be > > > > > using whatever mode it was passed in phydev->interface, which the MAC > > > > > sets when it calls the connection function. If the PHY dynamically > > > > > changes its host side mode as a result of what that line side is > > > > > doing, it should also change phydev->interface. However, as far as i > > > > > can see, the mscc does not do this. > > > > > > > > > > > > > Once the PHY auto-negotiates parameters such as speed and duplex mode > > > > with its link partner over the copper link as per IEEE 802.3 Clause 27, > > > > the link partner’s capabilities are then transferred by PHY to MAC > > > > over 1000BASE-X or SGMII link using the auto-negotiation functionality > > > > defined in IEEE 802.3z Clause 37. > > > > > > None of this allows you to distinguish between 1000BASE-X, SGMII and > > > QSGMII, which is what the commit message says. > > > > > > > I agree, the current commit message is misleading. > > > > > It does allow you to get duplex, pause, and maybe speed via in band > > > signalling. But you should also be getting the same information out of > > > band, via the phylib callback. > > > > > > There are some MACs which don't seem to work correctly without the in > > > band signalling, so maybe that is your problem? Please could you give > > > more background about your problem, what MAC and PHY combination are > > > you using, what problem you are seeing, etc. > > > > > > > MAC implementation[1] in a lot of NXP SoCs comes with in-band aneg enabled > > by default, and it does expect Clause 37 auto-negotiation to complete > > between MAC and PHY before the actual data transfer happens. > > > > [1] https://community.nxp.com/pwmxy87654/attachments/pwmxy87654/t-series/3241/1/AN3869(1).pdf > > > > I faced such issue while integrating VSC85xx PHY > > with one of the recent NXP SoC having similar MAC implementation. > > Not sure if this is a problem on MAC side or PHY side, > > But having Clause 37 support should help in most cases I believe. > > Clause 37 is 1000BASE-X negotiation, which is different from SGMII - a > point which is even made in your PDF above in section 1.1. > > You will need both ends to be operating in SGMII mode for 10M and 100M > to work. If one end is in 1000BASE-X mdoe and the other is in SGMII, > it can appear to work, but it won't be working correctly. > > Please get the terminology correct here when talking about SGMII or > 1000BASE-X. > Thank you for the clarification. Really appreciate it. Cheers, Raag > -- > RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ > FTTP is here! 40Mbps down 10Mbps up. Decent connectivity at last!