Availability and Performance of IEEE 1588 Clock Synchronization Solutions for Embedded Operating Systems 

Author: Tamas Kovacshazy

IEEE 1588 and the derived IEEE 802.1AS protocols are the de jure and de facto standards of precision time synchronization today in wired network embedded systems. The upcoming IEEE Time Sensitive Network (TSN) standard for Ethernet based dependable and real-time network embedded systems is also founded on IEEE 1588 time synchronization related technologies (modified version of IEEE 802.1AS is a part of the standard). First the operation and configuration options of IEEE 1588 introduced in the presentation and they are characterized from the point of view of performance (especially in case of fault scenarios) and also from the perspective of algorithmic and implementation complexity.
In the second part we detail the relationship of IEEE 1588 implementation and the operating system. This aspect is interesting because as TSN gains acceptance there will be operating system level changes needed to map real-time communication to real-time task execution. We show how IEEE 1588 components such as slave or master clock, boundary clocks and transparent clocks can be implemented and used on Linux on various architecture such as x86, ARM based SoCs, etc. We detail the HW and software requirements, such as timestamp unit related hardware requirements, driver requirements, kernel version dependencies, etc. The x86 and the ARM (Beaglebone) platforms are used as demonstration for Linux. Some insights about implementation on FreeRTOS and lwIP also is presented.
The proposed presentation is already available in an extended form so if it fits the program of Winter School on Operating Systems, it can be given there as a lecture.