Latency-guided on-chip bus network design

Deep submicron technology scaling has two major ramifications on the design process. First, reduced feature size significantly increases wire delay, thus resulting in critical paths being dominated by global interconnect rather than gate delays. Second, ultra high level of integration mandates design of systems-on-chip that encompass numerous intra-synchronous blocks with decreased functional granularity and increased communication demands. To address these issues we have developed an on-chip bus network design methodology and corresponding set of tools which, for the first, time, close the synthesis loop between system and physical design. The approach has three components: a communication profiler, a bus network designer, and a fast approximate floorplanner. The communication profiler collects run-time information about the traffic between system cores. The bus network design component optimizes the bus network structure by coordinating information from the other two components. The floorplanner aims at creating a feasible floorplan and to communicate information about the most constrained parts of the network.