Research On TSV Fault-Tolerant Routing Algorithm For Irregular 3D NoC Topology Structure Based On The Strategy Of Vertical First

3D NoC (Network on Chip) possesses the advantages of 3D IC and NoC, such as low power, low latency, high integration, good expansibility and so on. Because of the difference in the area and function of some components in each layer, it’s hard to keep a consistent layout of the network nodes. It led to only a few of router nodes connecting with up-layers and down-layers by TSVs. On the other hand, the manufacturing technique of TSV is immature, the manufacturing cost is high, and the TSVs could be destroyed easily in the stages of madding and using. Therefore, we should use small amount of TSVs to guarantee the normal communication. We propose to solve the communication problem of this irregular 3D NoC and to tolerant the TSVs fault.In order to solve the problems of the communication, TSV defect and the congestion in vertical channels in the irregular 3D No, we proposes a method to establish Channel Table based on the interconnecting situation of TSVs. There is a Channel Table in each node Which records a suitable vertical channel node. For the ordinary nodes without vertical channels, their Channel Tables record the address of the nearest upward channel node and the nearest downward channel node. For the nodes with vertical channel, their Channel Tables record the address of an available upward channel node and an available downward channel node, in case of TSV defect and congestion in vertical channel. For searching the shortest loop of upward channel nodes and downward channel nodes in the establishing process of Channel Table, we propose a method of greedy algorithm based on outlying first to solve this problem. The experiment result shows that the length of loop by using the method which present in this dissertation is up to at least 15% shorter than that using traditional greedy algorithm.Using the Channel Table proposed in this paper, we proposed a TSV fault-tolerant routing algorithm for irregular 3D NoC topology structure based on the strategy of vertical first. When the node is without vertical channel or TSV defects or the vertical channel is congested, packets will be transferred by a suitable channel node by searching Channel Table The experiment results show that the routing algorithm can solve the problem of the communication in the irregular 3D NoC. Its performance is better, and the area cost is only a litter bigger than traditional method.