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=-3.5 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS 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 3CBB1C1B0D8 for ; Thu, 10 Dec 2020 15:01:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E261E2310D for ; Thu, 10 Dec 2020 15:01:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389947AbgLJPBC (ORCPT ); Thu, 10 Dec 2020 10:01:02 -0500 Received: from esa.microchip.iphmx.com ([68.232.154.123]:28279 "EHLO esa.microchip.iphmx.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729979AbgLJPAx (ORCPT ); Thu, 10 Dec 2020 10:00:53 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=microchip.com; i=@microchip.com; q=dns/txt; s=mchp; t=1607612453; x=1639148453; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=UqMkvKL7D8SiD3dwz7dJFaadhU8wN/9oUbsLA7y6BBs=; b=h0ql8Y8Mr2FEnK6WNEwyVgedGxs3JutllsUqxQL4XHEz+RulKBJnwU79 ozE4anMARd5NGJ7p23KEL/phBZ4r0LmHhXbTmlNh7jUSL2+Gt8Xhswghk N1+MvvSpzA4dXw7YrvDnrfDQa/ahgzvqY8gW6cD1vfdHtitZXxNa6GXOl PGFgE5lGeQNnj+gDfLtmfkePlUjvhxT9lwOKiUS2+0y1DWDFcN2ACVtbq Dn25wqvke324/6lr302F7r1Hosv/OV5vdO0PMC9lF8u2mlQPzmDCQh5Hf tzXdZjdMTWXIVZSl5fBHJQJwCMq9rD5HcgAZhTNkgrDyEuoXvy1NGdgwN A==; IronPort-SDR: R3MJaP3nvzHZiidlIW4RrQ7dWRWphe6WNKjns6lRGwVl67uDBH1GvIQ5YmIHTkqYmUfE0wRLDc kInbCicGpSSFFjeHQxGlInx6cNvrsz64ClS3jGpWs25RVDGkvIJVBNPWsxq7rGt4S5GQW+RyiU VdlKiwdO1k5LNzChrE6WPp2SPJcYlzMbGg2Qe2vc3GbnLUw2ZBEcwusVYF3KIF7I+UCn5dtLE8 iu08kAFZUgviptzKSklFTEpjOo8b7wZhgJpaf6T8Zbi+gazz1XPtmj1TPxkLZQMbImhyZaPD2A T58= X-IronPort-AV: E=Sophos;i="5.78,408,1599548400"; d="scan'208";a="96633051" Received: from smtpout.microchip.com (HELO email.microchip.com) ([198.175.253.82]) by esa4.microchip.iphmx.com with ESMTP/TLS/AES256-SHA256; 10 Dec 2020 07:59:37 -0700 Received: from chn-vm-ex03.mchp-main.com (10.10.85.151) by chn-vm-ex04.mchp-main.com (10.10.85.152) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1979.3; Thu, 10 Dec 2020 07:59:37 -0700 Received: from localhost (10.10.115.15) by chn-vm-ex03.mchp-main.com (10.10.85.151) with Microsoft SMTP Server id 15.1.1979.3 via Frontend Transport; Thu, 10 Dec 2020 07:59:36 -0700 Date: Thu, 10 Dec 2020 15:59:35 +0100 From: Steen Hegelund To: Andrew Lunn CC: Kishon Vijay Abraham I , Vinod Koul , , Alexandre Belloni , Lars Povlsen , Bjarni Jonasson , Microchip UNG Driver List , , Subject: Re: [PATCH v9 3/4] phy: Add Sparx5 ethernet serdes PHY driver Message-ID: <20201210145935.see4n6csnomsl2rx@mchp-dev-shegelun> References: <20201207121345.3818234-1-steen.hegelund@microchip.com> <20201207121345.3818234-4-steen.hegelund@microchip.com> <20201210021134.GD2638572@lunn.ch> <20201210125706.saub7c2rarifhbx4@mchp-dev-shegelun> <20201210141610.GG2638572@lunn.ch> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8"; format=flowed Content-Disposition: inline In-Reply-To: <20201210141610.GG2638572@lunn.ch> Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On 10.12.2020 15:16, Andrew Lunn wrote: >EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe > >> > So why are returning link up information? >> >> Yes that was a bit of a hijacking of the function. I will remove that. >> I also removed the dependency on this behaviour in the client driver in the >> meantime. >> >> I think a status function on the generic phy would be useful, but I will >> take that as separate issue. > >In this context of an Ethernet SERDES, do you actually need it? You >would normally look at the PCS link status to determine if the link is >up. But it is useful debug information. If the PCS is down, but the >PHY indicates up, you can guess you have a protocol misconfiguration. Yes - you are probably right about that. I have been exposing this via a procfs interface during the development phase, and it was really useful to have, to track down the origin of the problem in certain situations. But on a system level, the PCS link would have the final say anyway. > >What exactly does link at this level mean? And thinking of the wider >uses of the PHY subsystem, what would link mean at this level for >SATA, PCIe, USB? Don't these all have some protocol level above >similar to Ethernet PCS which is the real determiner of link? Yes - I think this is really only a debug feature. No need to force this on the other PHY categories. > > Andrew Thanks for your comments, Andrew. BR Steen --------------------------------------- Steen Hegelund steen.hegelund@microchip.com