Design of write merging and read prefetching buffer in DRAM controller for embedded processor

Write merging and read prefetching are effective methods for improving processor performance, and they are mainly used in processors for desktop or server. As embedded system requires more powerful microprocessor, how to improve the performance of embedded processor is worthy of concern. This paper presents the architecture of write merging and read prefetching buffer in DRAM controller for embedded processor. The evaluation model is constructed, and the result demonstrates that the proposed method can reduce cache miss penalty dramatically. Additionally, the design of DRAM controller with write merging and read prefetching buffer is implemented and verified on FPGA platform, it can reduce CPI by 19.6% on average. Moreover, the RTL module of presented design is synthesized by Design Compiler, and synthesis result shows that hardware cost of proposed architecture is relatively small compared to performance amelioration.