From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754928AbbB0RWp (ORCPT ); Fri, 27 Feb 2015 12:22:45 -0500 Received: from mail.linn.co.uk ([195.59.102.251]:54712 "EHLO mail.linn.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752069AbbB0RWn (ORCPT ); Fri, 27 Feb 2015 12:22:43 -0500 Message-ID: <54F0A7DB.9070103@linn.co.uk> Date: Fri, 27 Feb 2015 17:22:35 +0000 From: Stathis Voukelatos User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.4.0 MIME-Version: 1.0 To: , , Subject: Re: [PATCH net-next v4 0/3] Linn Ethernet Packet Sniffer driver References: <20150225151945.GB7703@localhost.localdomain> <20150225170127.GD7703@localhost.localdomain> <54EE0268.2040201@linn.co.uk> <20150225173053.GE7703@localhost.localdomain> In-Reply-To: <20150225173053.GE7703@localhost.localdomain> Content-Type: text/plain; charset="windows-1252"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [10.2.10.132] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Richard, On 25/02/15 17:30, Richard Cochran wrote: >> I need some more time to study your other suggestions regarding the >> PHY timestamping framework. > > From my (limited) understanding of your HW device, I should think that > it will work. The PHY time stamping subsystem is not the most obvious > code in the world. Please feel free to ask if you have any questions. > To summarize (and confirm my understanding) your suggestion is for the sniffer to be configured to match PTP packets and (similarly to the dp83640) return the Message Type and Sequence Id fields that will allow them to be matched to an sk_buf that has been passed from the stack. Then the sk_buf can be timestamped using the sniffer timestamp. The H/W does have the capability to do that. However, in order to implement it there will be some architectural changes needed in the kernel. This module cannot really pretend to be a PHY. In the real world it sits between the MAC and the PHY. > Thanks, > Richard > Thanks, Stathis