From mboxrd@z Thu Jan 1 00:00:00 1970 From: Denny Page Subject: Re: Extending socket timestamping API for NTP Date: Tue, 07 Feb 2017 17:52:52 -0800 Message-ID: References: <20170207140144.GA11233@localhost> <02874ECE860811409154E81DA85FBB5857D6DC87@ORSMSX115.amr.corp.intel.com> Mime-Version: 1.0 (Mac OS X Mail 10.2 \(3259\)) Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Cc: Miroslav Lichvar , "netdev@vger.kernel.org" , Richard Cochran , Jiri Benc , Willem de Bruijn To: "Keller, Jacob E" Return-path: Received: from st11p06im-asmtp001.me.com ([17.172.125.149]:60808 "EHLO st11p06im-asmtp001.me.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932644AbdBHBxU (ORCPT ); Tue, 7 Feb 2017 20:53:20 -0500 Received: from process-dkim-sign-daemon.st11p06im-asmtp001.me.com by st11p06im-asmtp001.me.com (Oracle Communications Messaging Server 7.0.5.38.0 64bit (built Feb 26 2016)) id <0OL100R0095M4500@st11p06im-asmtp001.me.com> for netdev@vger.kernel.org; Wed, 08 Feb 2017 01:52:55 +0000 (GMT) In-reply-to: <02874ECE860811409154E81DA85FBB5857D6DC87@ORSMSX115.amr.corp.intel.com> Sender: netdev-owner@vger.kernel.org List-ID: [Resend without rich text] > On Feb 07, 2017, at 09:45, Keller, Jacob E = wrote: >=20 > The main problem here is that most hardware that *can't* timestamp all = packets is pretty limited to timestamping only PTP frames. Most, but not all. The TI DP83630 doesn=E2=80=99t support timestamping = for all packets, but it does support either PTP or NTP: =3D=3D=3D 2.3.2.3 NTP Packet Timestamp The DP83630 may be programmed to timestamp NTP packets instead of PTP = packets. This operation is enabled by setting the NTP_TS_EN control in = the PTP_TXCFG0 register. When configured for NTP timestamps, the DP83630 = will timestamp packets with the NTP UDP port number rather than the PTP = port number (note that the device cannot be configured to timestamp both = PTP and NTP packets). One-Step operation is not supported for NTP = timestamps, so transmit timestamps cannot be inserted directly into = outgoing NTP packets. Timestamp insertion is available for receive = timestamps but must use a single, fixed location.=20 =3D=3D=3D Right now, there is no API to signal to the driver that NTP timestamping = is desired. Even if the hardware does not directly support filtering, it can be = implemented in the driver. Denny=