From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757755AbdACKU7 (ORCPT ); Tue, 3 Jan 2017 05:20:59 -0500 Received: from mail-wm0-f66.google.com ([74.125.82.66]:36245 "EHLO mail-wm0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757670AbdACKUu (ORCPT ); Tue, 3 Jan 2017 05:20:50 -0500 Date: Tue, 3 Jan 2017 11:20:44 +0100 From: Richard Cochran To: Harini Katakam Cc: Nicolas Ferre , Rafal Ozieblo , Andrei Pistirica , "netdev@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , "davem@davemloft.net" , "harini.katakam@xilinx.com" , "punnaia@xilinx.com" , "michals@xilinx.com" , "anirudh@xilinx.com" , "boris.brezillon@free-electrons.com" , "alexandre.belloni@free-electrons.com" , "tbultel@pixelsurmer.com" Subject: Re: [RFC PATCH net-next v4 1/2] macb: Add 1588 support in Cadence GEM. Message-ID: <20170103102044.GB24780@localhost.localdomain> References: <1481720175-12703-1-git-send-email-andrei.pistirica@microchip.com> <20170102113155.GA16373@localhost.localdomain> <0717c63b-2e29-9ad1-7f01-39817980933f@atmel.com> <20170102161359.GD3609@localhost.localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jan 03, 2017 at 10:36:11AM +0530, Harini Katakam wrote: > I understand that it is not accurate - it is an initial version. No, it is not inaccurate at all, it is WRONG. This means that time stamps will be randomly associated with PTP network packets. To the application, the protocol will appear to work, but the time stamp information (and thus the synchronization) will be wrong. To me, this is unacceptable, and I will push back on this driver getting merged. [ In contrast, the descriptor based approach would be ok, afaict. ] Thanks, Richard