From mboxrd@z Thu Jan 1 00:00:00 1970 From: Richard Cochran Subject: Re: [RFC PATCH net-next v4 1/2] macb: Add 1588 support in Cadence GEM. Date: Tue, 3 Jan 2017 11:20:44 +0100 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 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" To: Harini Katakam Return-path: Content-Disposition: inline In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.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