The Implementation Of Bridge Chip For Interconnection With Godson-3A Multi-chip And Study For Coherence

CC-NUMA (cache coherent non-uniform memory access) applied on Godson-3A processors has got a good performance, programming, as well, significantly simplified. However, keeping on-chip and off-chip data transmission stable and accurate, also has some work that needs to continue analyzing and studying on the structure of chip-to-chip interconnection based on coherence protocol. In order to construct for larger scale expansion of CC-NUMA system, coherence should be kept among multiple processors. With the bridge chip, it gathers to control and guarantees global data coherence for crossing systems, and improve the performance of memory access. The bridge chip that designed is partly similar to the Godson-3A’s second level cache. The function of the bridge chip is verified through the directional and random test.(1) With analysis of existing models of consistence, transplanting message-processing mechanism of the godson-3A secondary cache module to the bridge chip, so that it gains a better compatibility of unified management for multi-chip and multi-system by godson-3A processor.(2) Modifying cache coherence module of bridge chip and constructing corresponding verification environment.(3) Designing a routing algorithm of bridge chip to implement16bridge chip interconnection with no conflict and constructing environment to verity the correct function.