[PATCH v6 0/4] PTP protocol support in lib/net

[Rajesh Kumar <rajesh3.kumar@intel.com>]

Add IEEE 1588-2019 Precision Time Protocol (PTP) support to DPDK via a
new header library in lib/net/. This patchset provides wire-format packet
structure definitions and inline helpers for Transparent Clock and
ordinary clock applications.

## Design Rationale

Following DPDK conventions for protocol libraries (rte_tcp.h, rte_ip.h),
PTP definitions are provided as a header-only library with inline functions
for zero-overhead packet processing. All functions are suitable for
real-time, performance-critical code paths.

## Contents

**Patch 1:** lib/net/rte_ptp.h - Header structures and inline helpers
  - rte_ptp_port_id: 10-byte port identity with EUI-64 clock ID
  - rte_ptp_hdr: 34-byte PTP v2 common message header
  - rte_ptp_timestamp: 10-byte nanosecond-precision timestamp
  - Message type constants (Sync, Delay_Req, Announce, etc.)
  - Flag field bits (two-step, unicast, leap indicator)
  - Inline helpers: rte_ptp_msg_type(), rte_ptp_seq_id(), rte_ptp_is_event(),
    rte_ptp_correction_ns(), rte_ptp_add_correction(), rte_ptp_timestamp_to_ns()

**Patch 2:** examples/ptp_tap_relay_sw - Software PTP Transparent Clock relay
  - Relays PTP packets between a DPDK-bound physical NIC and Linux TAP interface
  - Software timestamp-based residence time measurement (CLOCK_MONOTONIC)
  - Accumulates residence time to PTP correctionField per IEEE 1588-2019 §10.2
  - Handles L2, VLAN/QinQ, UDP/IPv4, UDP/IPv6 PTP encapsulations
  - Works with unmodified Linux kernel and stock DPDK (no patches required)
  - Compatible with standard linuxptp (ptp4l) tooling

**Patch 3:** doc/guides/rel_notes/release_26_07.rst - Release notes update

**Patch 4:** examples/ptpclient - Update to use lib/net PTP definitions
  - Uses RTE_ETHER_TYPE_1588 constant
  - Adds lib/net dependency

## Testing

- Build: `ninja -C build` — clean compilation
- Examples: Both ptpclient and ptp_tap_relay_sw compile and link correctly
- No stale references to old patterns or removed functions

## Changelog

v6 changes:
  - Restructured to lib/net (header-only, following lib/net conventions)
  - Removed separate DPI library functions (moved to example-local ptp_parse.h)
  - Removed app/test unit tests (library now header-only, example-driven testing)
  - Removed programmer's guide doc (lib/net headers use Doxygen API docs only)

Rajesh Kumar (4):
  lib/net: add IEEE 1588 PTP v2 protocol header definitions
  examples/ptp_tap_relay_sw: add PTP software transparent clock relay
  doc: update release notes for PTP protocol library
  examples/ptpclient: use shared PTP library definitions

 MAINTAINERS                                   |   6 +
 doc/guides/rel_notes/release_26_07.rst        |  12 +
 doc/guides/sample_app_ug/ptp_tap_relay_sw.rst | 212 +++++++++
 examples/ptp_tap_relay_sw/Makefile            |  41 ++
 examples/ptp_tap_relay_sw/meson.build         |  13 +
 examples/ptp_tap_relay_sw/ptp_parse.h         | 211 +++++++++
 examples/ptp_tap_relay_sw/ptp_tap_relay_sw.c  | 432 ++++++++++++++++++
 examples/ptpclient/meson.build                |   1 +
 examples/ptpclient/ptpclient.c                |   4 +-
 lib/net/meson.build                           |   1 +
 lib/net/rte_ptp.h                             | 264 +++++++++++
 11 files changed, 1195 insertions(+), 2 deletions(-)
 create mode 100644 doc/guides/sample_app_ug/ptp_tap_relay_sw.rst
 create mode 100644 examples/ptp_tap_relay_sw/Makefile
 create mode 100644 examples/ptp_tap_relay_sw/meson.build
 create mode 100644 examples/ptp_tap_relay_sw/ptp_parse.h
 create mode 100644 examples/ptp_tap_relay_sw/ptp_tap_relay_sw.c
 create mode 100644 lib/net/rte_ptp.h

-- 
2.53.0