80 lines
2.3 KiB
ReStructuredText
80 lines
2.3 KiB
ReStructuredText
.. _gptp_interface:
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generic Precision Time Protocol (gPTP)
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######################################
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.. contents::
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:local:
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:depth: 2
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Overview
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********
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This gPTP stack supports the protocol and procedures as defined in
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the `IEEE 802.1AS-2011 standard`_ (Timing and Synchronization for
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Time-Sensitive Applications in Bridged Local Area Networks).
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Supported features
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*******************
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The stack handles communications and state machines defined in the
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`IEEE 802.1AS-2011 standard`_. Mandatory requirements for a full-duplex
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point-to-point link endpoint, as defined in Annex A of the standard,
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are supported.
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The stack is in principle capable of handling communications on multiple network
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interfaces (also defined as "ports" in the standard) and thus act as
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a 802.1AS bridge. However, this mode of operation has not been validated on
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the Zephyr OS.
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Supported hardware
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******************
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Although the stack itself is hardware independent, Ethernet frame timestamping
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support must be enabled in ethernet drivers.
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Boards supported:
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- :zephyr:board:`frdm_k64f`
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- :zephyr:board:`nucleo_h743zi`
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- :zephyr:board:`nucleo_h745zi_q`
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- :zephyr:board:`nucleo_f767zi`
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- :zephyr:board:`sam_e70_xplained`
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- :ref:`native_sim` (only usable for simple testing, limited capabilities
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due to lack of hardware clock)
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- :zephyr:board:`qemu_x86` (emulated, limited capabilities due to lack of hardware clock)
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Enabling the stack
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******************
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The following configuration option must me enabled in :file:`prj.conf` file.
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- :kconfig:option:`CONFIG_NET_GPTP`
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Application interfaces
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**********************
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The following Application Interfaces as defined in section 9 of the standard
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are available:
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- ``ClockSourceTime`` interface (:c:func:`gptp_clk_src_time_invoke`)
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- ``ClockTargetPhaseDiscontinuity`` interface (:c:func:`gptp_register_phase_dis_cb`)
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- ``ClockTargetEventCapture`` interface (:c:func:`gptp_event_capture`)
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Testing
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*******
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The stack has been informally tested using the
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`OpenAVnu gPTP <https://github.com/AVnu/gptp>`_ and
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`Linux ptp4l <http://linuxptp.sourceforge.net/>`_ daemons.
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The :zephyr:code-sample:`gPTP sample application <gptp>` from the Zephyr
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source distribution can be used for testing.
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.. _IEEE 802.1AS-2011 standard:
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https://standards.ieee.org/findstds/standard/802.1AS-2011.html
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API Reference
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*************
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.. doxygengroup:: gptp
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