AMD Solarflare Enhanced PTP Daemon

The sfptpd service synchronises local clocks together with multiple PTP and PPS sources in one integrated application with high quality timestamp filtering and supports LACP and active-backup bonds with and without VLANs. The default and Enterprise PTP profiles are supported.

Instantaneous and long term statistics along with support for 'NetSync Monitor', a built-in OpenMetrics exporter and standard PTP event monitoring are available to support integrating with monitoring solutions.

Integration is provided to work with NTP sources via ntpsec, ntpd and subject to limitations, chronyd. The daemon works on Linux systems for 3.0 kernels and later.

See the changelog for recent additions to sfptpd. The current stable branch is v3_9.

For a quick start (operating PTP on bond0, domain 100), see one line docker example.

Building and running from source

Sfptpd uses elements of C23 compatible with gcc-11 and later.

1. Change directory to the root of the sfptpd source repository or package
2. Type make all
3. The executable daemon is sfptpd in the build/ directory

The built sfptpd daemon does not require installation. However, it must normally be started as root.

Example installation recipies may be found in INSTALL.md and examples configuration files under config.

A simple back-to-back PTP example:

# On host A:
sudo build/sfptpd -i eth1 -f config/ptp_master_freerun.cfg

# On host B, first disabling ntpd and chronyd for simplicity:
for i in ntp{,d} chrony{,d}; do sudo service $i stop 2>/dev/null; done
sudo build/sfptpd -i eth1 -f config/ptp_slave.cfg

Supported releases

Supported releases of sfptpd are available from https://www.xilinx.com/download/drivers. These are supported by AMD for the Solarflare adapters and operating systems listed in the relevant release notes.

The user guide for supported releases is available at https://docs.xilinx.com/r/en-US/ug1602-ptp-user.

Community-supported usage

The sfptpd daemon provides a system-centric time sync solution that can be used with any network adapter and driver supporting standard Linux time APIs. The monolithic design of sfptpd enables a holistic approach to system time synchronisation, supporting link aggregation and integrating remote and local clock synchronisation.

Using non-Solarflare network adapters

Enable the use of non-Solarflare adapters with:

non_solarflare_nics on

By default, non-Solarflare adapters are not synchronised to avoid hitting a potential limitation with some drivers.

Sfptpd is normally configured to synchronise all available NIC clocks automatically so that applications can obtain meaningful hardware timestamps on all interfaces.

In the case of Solarflare NICs, the sfc net driver presents the same "PTP Hardware Clock" (PHC) device (e.g. /dev/ptp0) for each of the physical network ports on a single adapter. Some NICs, however, present separate and apparently independent PHC devices for each network port which actually represent the same underlying physical clock.

Workaround 1: list clocks explicitly

When using third party NICs affected by this issue, the recommended mitigation is to list explicitly the NIC clocks to be disciplined with clock_list.

Workaround 2: clock deduplication

An experimental option, phc_dedup on will identify duplicate PHC devices for a single underlying clock and retain only one which has effective control. This is achieved via a test that involes temporarily adjusting the relevant NIC clocks, so should not be done while those interfaces are in use by applications for timestamping (hardware timestamping will be disabled globally during this calibration period to enforce this).

Footnotes

SPDX-License-Identifier: BSD-3-Clause
SPDX-FileCopyrightText: (c) Copyright 2013-2025 Advanced Micro Devices, Inc.

This software is licensed as BSD-3-Clause AND BSD-2-Clause AND NTP AND ISC. See LICENSE file for details.