Prime turn model and first last turn model: An adaptive deadlock free routing for network-on-chips

Abstract

Purpose: Network-on-Chips (NoCs) have emerged as a valuable solution for the never-ending communication needs of large System-on-Chips (SoCs). It opened the doors for scalability, resource management, bandwidth, and power management for communication technologies. The performance and efficiency of NoCs is largely determined by the routing mechanism it uses to transfer the data. There occur many challenges while designing a routing algorithm, deadlock being one among them. Deadlock is one of the most frequently occurring and difficult to handle problem in NoCs. Hence the deployment of deadlock-free algorithms is necessary for the fruitful functioning of NoCs. In this paper, we are discussing multiple deadlock handling techniques, with a focus on deadlock prevention. Further, we have developed two models namely Prime Turn Model and First Last Turn Model for 2D meshes. Both these turn models are adaptive and deadlock-free. No virtual channels are used for deadlock prevention. The behavior and working of turn models along with pseudocode and simulations are all provided. They are compared with different already existing turn models for different traffic patterns. Simulation results show that our routing algorithms obtain good improvement in terms of latency and throughput and hence enhance performance.