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 C55C7E7D0AA for ; Thu, 21 Sep 2023 21:06:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232624AbjIUVGP (ORCPT ); Thu, 21 Sep 2023 17:06:15 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35392 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232679AbjIUVEp (ORCPT ); Thu, 21 Sep 2023 17:04:45 -0400 Received: from vps0.lunn.ch (vps0.lunn.ch [156.67.10.101]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C262DAFC11; Thu, 21 Sep 2023 11:07:50 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lunn.ch; s=20171124; h=In-Reply-To:Content-Disposition:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:From:Sender:Reply-To:Subject: Date:Message-ID:To:Cc:MIME-Version:Content-Type:Content-Transfer-Encoding: Content-ID:Content-Description:Content-Disposition:In-Reply-To:References; bh=NQXiZoHMCblnzW0FheGDzK8ZNsxJFNqugzxVPC1fy1I=; b=iIe0qoEAImcIE+rWAmnZ8xPO0W h7aRx1fUHew4bud6BGsi+v+ohOeiHSveI/FFZ5SyKv1kbc7VK83hD5MIgl8bSRk2MWkP40bLCLZKQ g5jPLEsA23tIcvia6u+LA4GTrpUy6SatHC/Edfnef7Y1TbnnVE/MEsgyVz7ZqKpkc/mo=; Received: from andrew by vps0.lunn.ch with local (Exim 4.94.2) (envelope-from ) id 1qjJWF-0075Vg-FS; Thu, 21 Sep 2023 15:14:59 +0200 Date: Thu, 21 Sep 2023 15:14:59 +0200 From: Andrew Lunn To: Choong Yong Liang Cc: Rajneesh Bhardwaj , David E Box , Hans de Goede , Mark Gross , Jose Abreu , Heiner Kallweit , Russell King , "David S . Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Marek =?iso-8859-1?Q?Beh=FAn?= , Jean Delvare , Guenter Roeck , Giuseppe Cavallaro , Alexandre Torgue , Jose Abreu , Maxime Coquelin , Richard Cochran , Philipp Zabel , Alexei Starovoitov , Daniel Borkmann , Jesper Dangaard Brouer , John Fastabend , Wong Vee Khee , Jon Hunter , Jesse Brandeburg , Revanth Kumar Uppala , Shenwei Wang , Andrey Konovalov , Jochen Henneberg , David E Box , Andrew Halaney , Simon Horman , Bartosz Golaszewski , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, linux-stm32@st-md-mailman.stormreply.com, linux-arm-kernel@lists.infradead.org, platform-driver-x86@vger.kernel.org, linux-hwmon@vger.kernel.org, bpf@vger.kernel.org, Voon Wei Feng , Tan Tee Min , Michael Sit Wei Hong , Lai Peter Jun Ann Subject: Re: [PATCH net-next v3 0/5] TSN auto negotiation between 1G and 2.5G Message-ID: <4caade36-d4be-4670-ac79-d9d00488293d@lunn.ch> References: <20230921121946.3025771-1-yong.liang.choong@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230921121946.3025771-1-yong.liang.choong@linux.intel.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > Auto-negotiation between 10, 100, 1000Mbps will use > in-band auto negotiation. Auto-negotiation between 10/100/1000Mbps and > 2.5Gbps will work as the following proposed flow, the stmmac driver reads > the PHY link status registers then identifies the negotiated speed. I don't think you replied to my comment. in-band is just an optimisation. It in theory allows you to avoid a software path, the PHY driver talking to the MAC driver about the PHY status. As an optimisation, it is optional. Linux has the software path and the MAC driver you are using basically has it implemented. Why use this odd mix of in-band and out of band? It seems the change will be simpler if you just use the out of band method all the time and ignore in-band. Andrew