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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id E4B6BC47422 for ; Mon, 29 Jan 2024 13:13:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:Content-Type: Content-Transfer-Encoding:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:From:References:Cc:To:Subject: MIME-Version:Date:Message-ID:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=MOxujYgHOKnIt5wbM++ghMFVNR5LlyKWALldGfZX0zk=; b=r5BRIcPWIhNW7V SEwEvEi0bMu0xHOYZacytVOMArxf5ImfhSVD8iyj2nI1Bs8EKNt/6TWIG+gUsDl7DzSfnBki79PCc CI3cAhXlG0uCY9kYImEnrJVAQM5vWC0MEPcP5e6/6hi1xGcnMDV+balemz5qwh1X23/j09SjgrJ49 EzGV0p6sOyq1nRTLxe43eFkcvHF8qEHkdPfDikbrXGtrr9aLDqYhdhkiChebxHXM/y7Iw7hq455T+ Dl9o9+gcQouLoSsaOOUJiN/CDa1o3YuAkjEeWnrFUyCTJQ1lYnm7VegEsaqESaTDhEhmY86X4+qeV ZWtCHht66x9vjr+30+8g==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1rURSM-0000000CoOh-0KqR; Mon, 29 Jan 2024 13:13:46 +0000 Received: from mgamail.intel.com ([198.175.65.12]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1rURSI-0000000CoNC-2g4u for linux-arm-kernel@lists.infradead.org; Mon, 29 Jan 2024 13:13:43 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1706534023; x=1738070023; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=1A2kwv15wQygVVOoqucjQOG6yZvrsKLSOxdqdrtflpo=; b=UebmlhW/roSiaWX49NsJceJ3udFzS24b+Tcr2D0LED9oIqp/2GJexqMy mgYqLZ8O4fvajLn3G94FIJhXjjY479TFVP48xVLJvBRhpyT1LfnDV4x1q EdwDwHBYL4FFJvsUGjdZdWwVCK4RBhIBqYZgmhuAon35fa4cN1jpcbqqz FMnbo9cUpObD1W2ts2psX8aLOiTgoiSFTp9AEPKYarpjm36dbyfRaMUwh x1IIwCR5dB4ab2Dsxkhrc0FH3pZ0Qx2OwUoYNAbtFisQcmxbEJNXB7ici /Qm0Okx8ycOtDIrRntN0xul3TQ7I3tPFrfW4kGGiYgxCanRYd5H/ItKmj w==; X-IronPort-AV: E=McAfee;i="6600,9927,10967"; a="10328498" X-IronPort-AV: E=Sophos;i="6.05,227,1701158400"; d="scan'208";a="10328498" Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by orvoesa104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 29 Jan 2024 05:13:42 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10967"; a="878068306" X-IronPort-AV: E=Sophos;i="6.05,227,1701158400"; d="scan'208";a="878068306" Received: from choongyo-mobl.gar.corp.intel.com (HELO [10.247.122.111]) ([10.247.122.111]) by fmsmga003-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 29 Jan 2024 05:13:28 -0800 Message-ID: <41f08e94-3a0b-442b-be79-d30579f3e12d@linux.intel.com> Date: Mon, 29 Jan 2024 21:13:28 +0800 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH net-next v3 0/5] TSN auto negotiation between 1G and 2.5G Content-Language: en-US To: "Russell King (Oracle)" , Andrew Lunn Cc: Rajneesh Bhardwaj , David E Box , Hans de Goede , Mark Gross , Jose Abreu , Heiner Kallweit , "David S . Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , =?UTF-8?Q?Marek_Beh=C3=BAn?= , 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 References: <20230921121946.3025771-1-yong.liang.choong@linux.intel.com> <4caade36-d4be-4670-ac79-d9d00488293d@lunn.ch> From: Choong Yong Liang In-Reply-To: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240129_051342_797308_7DD92D87 X-CRM114-Status: GOOD ( 17.97 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 21/9/2023 10:09 pm, Russell King (Oracle) wrote: > On Thu, Sep 21, 2023 at 03:14:59PM +0200, Andrew Lunn wrote: >>> 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. > > Sorry Andrew, I have to disagree. It isn't always optional - there are > PHYs out there where they won't pass data until the in-band exchange > has completed. If you try to operate out-of-band without the PHY being > told that is the case, and program the MAC/PCS end not to respond to > the in-band frames from the PHY, the PHY will report link up as normal > (since it reports the media side), but no data will flow because the > MAC facing side of the PHY hasn't completed. > > The only exception are PHYs that default to in-band but have an inband > bypass mode also enabled to cover the case where the MAC/PCS doesn't > respond to the inband messages. > Russell is correct, we did set out-of-band for PCS and configured MAC. Due to the PHY not being completed, there will be no data flow through. _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel