Cost-Effective Memory Architecture to Achieve Flexible Configuration and Efficient Data Transmission for Coarse-Grained Reconfigurable Array (Abstract Only)

The memory architecture has a significant effect on the flexibility and performance of a coarse-grained reconfigurable array (CGRA), which can be restrained due to configuration overhead and large latency of data transmission. Multi-context structure and data preloading method are widely used in popular CGRAs as a solution to bandwidth bottlenecks of context and data. However, these two schemes cannot balance the computing performance, area overhead, and flexibility. This paper proposed group-based context cache and multi-level data memory architectures to alleviate the bottleneck problems. The group-based context cache was designed to dynamically transfer and buffer context inside CGRA in order to relieve the off-chip memory access for contexts at runtime. The multi-level data memory was designed to add data memories to different CGRA hierarchies, which were used as data buffers for reused input data and intermediate data. The proposed memory architectures are efficient and cost-effective so that performance improvement can be achieved at the cost of minor area overhead. Experiments of H.264 video decoding program and scale invariant feature transform algorithm achieved performance improvements of 19% and 23%, respectively. Further, the complexity of the applications running on CGRA is no longer restricted by the capacity of the on-chip context memory, thereby achieving flexible configuration for CGRA. The memory architectures proposed in this paper were based on a generic CGRA architecture derived from the characteristics found in the majority of existing popular CGRAs. As such, they can be applied to universal CGRAs.