Design of TSN-based Ethernet Driver Working Model for Time-aware Scheduling

Abstract

With the rapid increase in the proportion of electronic products used in automobiles, the scale and complexity of in-car systems are increasing day by day. The requirements for automobile safety, energy conservation, emission reduction, and comfort are also growing. Under such a development trend, the bandwidth demand of the onboard network is also increasing. It demands that the onboard network can carry various high-speed data transmissions. To overcome this problem, automotive Ethernet becomes one of the best solutions in such a trend by establishing communication links between related ECUs, allowing ECUs to use more advanced functions and share data. Meanwhile, Time Sensitive Network (TSN) is dedicated to developing more powerful functions to realize an ultra-low delay control network. Time synchronization and time-aware scheduling are the core of TSN protocol. In this paper, we propose a new architecture of the TSN-based Ethernet driver working model for time-aware scheduling to improve the performance of the deterministic delays of the time-sensitive stream. TSN only guarantees the communication delay but does not make requirements for the controllers. To support the real-time scheduling mechanism of TSN, the Ethernet controller's working model must change. Due to the more considerable amount of data to be processed, the driver's occupation management of the controller's running resources becomes more critical. At the same time, due to the need for real-time scheduling, the message sending behavior is constrained, and it cannot run in the event-based triggering mode like traditional Ethernet drivers. We also implement our architecture on an embedded system and evaluate the performance of the time-aware scheduling based on our architecture.