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=-2.4 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 CBE78C4BA09 for ; Wed, 26 Feb 2020 02:54:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 942CF21744 for ; Wed, 26 Feb 2020 02:54:46 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="Z8DLeQ8v" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730047AbgBZCyp (ORCPT ); Tue, 25 Feb 2020 21:54:45 -0500 Received: from mail-pf1-f196.google.com ([209.85.210.196]:33303 "EHLO mail-pf1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727880AbgBZCyp (ORCPT ); Tue, 25 Feb 2020 21:54:45 -0500 Received: by mail-pf1-f196.google.com with SMTP id n7so661162pfn.0; Tue, 25 Feb 2020 18:54:44 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=WbBbZJtOAAR9ogSmr5inY5EiHXQEhBZaLqZLWsUeMHE=; b=Z8DLeQ8vr4YF3J/w3/lo+xEFAdWWokOTKo3Mqfc0IA4dpLgdjOC/XJBThtdjZEMzIp D2nw4fG2AFBeRDVIwePO+G8fsxbMgixyEy0yt5Pb1VOk/qSp1Sd1SvfSfcDD5bsfL2Nj MTBHgBehwVs/4AQcEbwR4w61KBZYMgVX2E+cBfYunc4e5+6rWhn9uhZz/aHPdF8ycGCa LJW1dIPll5dc6xE6UdT8NjKIeILz69ZhFScaF0mQkTM5Y4gRJ8JFf4VLxsQrwyxZmj9K E50108w4lLu3tQeNLmx7rVuVozH6UOimfgpCjSjn3UbFWUMyELMeiQdKavdivoQjDXl0 BFUg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=WbBbZJtOAAR9ogSmr5inY5EiHXQEhBZaLqZLWsUeMHE=; b=uSaA7jyNBussrtik20qnlXMFx3uezbvsfnOarIVa+FczjHZ6BrWLKrUl2EGfnWXQOw LQxxGFnLbOV578AgFFxkZ3UMx32/4Ethkxp6PyvhimZZ/dq0HNnsxaHm8js1b/fQ3xtC yUlb3nIobUWhzWIffCdGa7nQu7gnQtxqqjCoAOXmFCteNbu63yF0ydfwS1f/F+uSnubG paal/rGfel89pHc5bjsZ9dFdywK6Hc9Ic3v1e/sdZtb8ebae3DC3XvToLeEgaXYiwYYk aQOpTnFir6UZZ8D6VkL0tNAUYUHo0fs2dIZbGh22noq57T5/AgK0cCu+2gA9ymQLF+3P 6rmA== X-Gm-Message-State: APjAAAU9ETqYPr5AT1RPIfN+CDSrAPOxi0nzEH2o+4Y/0XHqvblLiuRC xYERwv+1vIKgD06tRIc8U3E= X-Google-Smtp-Source: APXvYqzDRk/zvtkM2zUmDrx/sUc0QZV4NiKmSYZvj1fKG58TZ+GxwTXEgoX72xhH4fBHxsmcjdLrtw== X-Received: by 2002:a63:8f1a:: with SMTP id n26mr1588449pgd.355.1582685683821; Tue, 25 Feb 2020 18:54:43 -0800 (PST) Received: from localhost (c-73-241-114-122.hsd1.ca.comcast.net. [73.241.114.122]) by smtp.gmail.com with ESMTPSA id o36sm370352pgl.24.2020.02.25.18.54.42 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 25 Feb 2020 18:54:43 -0800 (PST) Date: Tue, 25 Feb 2020 18:54:41 -0800 From: Richard Cochran To: Michael Walle Cc: Andrew Lunn , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Florian Fainelli , Heiner Kallweit , Russell King , "David S . Miller" Subject: Re: [RFC PATCH 0/2] AT8031 PHY timestamping support Message-ID: <20200226025441.GB10271@localhost> References: <20200225230819.7325-1-michael@walle.cc> <20200225235040.GF9749@lunn.ch> <9955C44A-8105-4087-8555-BAC5AE4AF25D@walle.cc> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <9955C44A-8105-4087-8555-BAC5AE4AF25D@walle.cc> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Feb 26, 2020 at 01:07:26AM +0100, Michael Walle wrote: > Am 26. Februar 2020 00:50:40 MEZ schrieb Andrew Lunn : > >That sounds fundamentally broken. Right. It can't work unless the PHY latches the time stamp. > This might be the case, but the datasheet (some older revision can > be found on the internet, maybe you find something) doesn't mention > it. Nor does the PTP "guide" (I don't know the exact name, I'd have > to check at work) of this PHY. Besides the timestamp there's also > the sequence number and the source port id which would need to be > read atomically together with the timestamp. Maybe the part is not intended to be used at all in this way? AFAICT, PHYs like this are meant to feed a "PTP frame detected" pulse into the time stamping unit on the attached MAC. The interrupt serves to allow the SW to gather the matching fields from the frame. Thanks, Richard