Multi-layer floorplanning for reconfigurable designs
Partial dynamic reconfiguration is an emerging area in field programmable gate arrays (FPGA) designs, which is used for saving device area and cost. In order to reduce the reconfiguration overhead, two consecutive similar sub-designs should be placed in the same locations to get the maximum reuse of common components. This requires that all the future designs be considered while floorplanning for any given design. A comprehensive framework for floorplanning designs on partial reconfigurable architecture is provided. Several reconfiguration-specific floorplanning cost functions and moves that aim to reduce the reconfiguration overhead are introduced. A new multi-layer sequence pair-representation-based floorplanner that allows overlap of static and non-static components of multiple designs and guarantees a feasible overlapping floorplan with minimal area packing is introduced. A new matching algorithm that covers all possible matchings of static blocks during floorplanning for multiple designs is presented. In our experiments, it is shown that the proposed floorplanner gives more than 50% savings in reconfiguration frames compared with the scheme where no reuse is done. Further, compared with a traditional sequential floorplanner, our floorplanner removes infeasibility in many designs, achieves an improvement of clock period by 12% on average and reduces the place and route time significantly. The proposed floorplanner could be used for finding high-quality floorplans for applications that use partial reconfiguration.