From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 703D0FBF9 for ; Mon, 15 May 2023 21:46:03 +0000 (UTC) Received: from pandora.armlinux.org.uk (pandora.armlinux.org.uk [IPv6:2001:4d48:ad52:32c8:5054:ff:fe00:142]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 25B5F10EC for ; Mon, 15 May 2023 14:45:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=armlinux.org.uk; s=pandora-2019; h=Sender:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date: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=W3TE4ccIZBaLyijVR8GPmMnmsWRf/mMHqj2NaoV8t1E=; b=Bz9orKkAmQvhzEvjgWOhLpC5+8 XDVRWXUdjF5ad9I4IzOv+EAQMokwJuzytLihdJnn0dLiIPCeF2sOa6bffUb+m5KMC1Z8UAmLIVx2j zOvjxTAFiHBOpl9l5MXu8l1KhP8AJlO0SBSqQxhCYi2lbMpkVaTurrarCs36pO8DmVukTdItiYS11 T5EZadEFot1wShkwkNMKjweQd6kFRZncw4yRJKBAzz1ETShaIuuuvzOrgBPMR6QNb4xJZscVHZSMo xBVwxPuFQyuhLhCzzeo4f4/cN8POmCJv7YuK/OQNYW6P9HhITDAzKVN9Eo73zeqyuBsQcr25lTDFw DscYXzYQ==; Received: from shell.armlinux.org.uk ([fd8f:7570:feb6:1:5054:ff:fe00:4ec]:51262) by pandora.armlinux.org.uk with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1pyg0W-0004fD-QR; Mon, 15 May 2023 22:45:28 +0100 Received: from linux by shell.armlinux.org.uk with local (Exim 4.94.2) (envelope-from ) id 1pyg0P-00006m-6q; Mon, 15 May 2023 22:45:21 +0100 Date: Mon, 15 May 2023 22:45:21 +0100 From: "Russell King (Oracle)" To: Vladimir Oltean Cc: Andrew Lunn , AngeloGioacchino Del Regno , Daniel Machon , "David S. Miller" , Eric Dumazet , Felix Fietkau , Florian Fainelli , Heiner Kallweit , Horatiu Vultur , Ioana Ciornei , Jakub Kicinski , John Crispin , Jose Abreu , Lars Povlsen , Lorenzo Bianconi , Marcin Wojtas , Mark Lee , Matthias Brugger , Maxime Chevallier , Paolo Abeni , Sean Wang , Steen Hegelund , Taras Chornyi , Thomas Petazzoni , UNGLinuxDriver@microchip.com, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, netdev@vger.kernel.org Subject: Re: [PATCH RFC] Providing a helper for PCS inband negotiation Message-ID: References: <20230515195616.uwg62f7hw47mktfu@skbuf> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230515195616.uwg62f7hw47mktfu@skbuf> Sender: Russell King (Oracle) X-Spam-Status: No, score=-4.4 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_MED,SPF_HELO_NONE, SPF_NONE,T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net On Mon, May 15, 2023 at 10:56:16PM +0300, Vladimir Oltean wrote: > Hello, > > On Mon, May 15, 2023 at 01:22:50PM +0100, Russell King (Oracle) wrote: > > 1. Should 10GBASE-KR be included in the SGMII et.al. case in the code? > > Any other interface modes that should be there? Obviously, > > PHYLINK_PCS_NEG_NONE is not correct for 10GBASE-KR since it does use > > inband AN. Does it make sense for the user to disable inband AN for > > 10GBASE-KR? If so, maybe it should be under the 1000base-X case. > > What physical process (reference to IEEE 802.3 clause is fine) would be > controlled by the phylink_pcs_neg_mode() function for the so-called > 10GBASE-KR phy-mode? Clause 73.1: "While implementation of Auto-Negotiation is mandatory for Backplane Ethernet PHY s, the use of Auto-Negotiation is optional." "The Auto-Negotiation function allows the devices to switch between the various operational modes in an orderly fashion, permits management to disable or enable the Auto-Negotiation function, and allows management to select a specific operational mode." "The Auto-Negotiation function also provides a parallel detection function to allow Backplane Ethernet devices to connect to other Backplane Ethernet devices that have Auto-Negotiation disabled and interoperate with legacy devices that do not support Clause 73 Auto-Negotiation." So, my reading of these statements is that the _user_ should be able to control via ethtool whether Clause 73 negotiation is performed on a 10GBASE-KR (or any other backplane link that uses clause 73 negotiation.) Having extracted that from 802.3, I now believe it should be treated the same as 1000BASE-X, and the Autoneg bit in ethtool should determine whether Clause 73 negotiation is used for 10GBASE-KR (and any other Clause 73 using protocol.) -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTP is here! 80Mbps down 10Mbps up. Decent connectivity at last!