Inside GateMate: Analysis and Benchmarking of a New FPGA Architecture
While modern FPGAs typically implement programmable logic using $\mathrm{4}-\mathrm{6}$-input LUTs, the Cologne Chip GateMate FPGA instead adopts a LUT-tree architecture, among several other distinctive features. We analyze its design trade-offs and support our findings with results from a targeted benchmark suite. LUT-trees prove less efficient for combinational logic than LUTs. Equivalent RTL designs (excluding DSPs) require ${1 0 - 3 0 \%}$ more programmable elements (CPEs) in GateMate than in comparable FPGAs. We observed a reduced logic-area efficiency, and the 1:1 flip-flop (FF) to logic ratio yields $30 \% \text{FF}$ under-utilization across diverse RTL designs. Comparative evaluation with a peer FPGA demonstrates that GateMate is suited for deeply pipelined applications with modest DSP and control requirements. Lack of timing-driven place and route, distributed RAM and DSP blocks limits usability for arithmetic-heavy, monolithic designs. We conclude that its dual-port block RAM and FF-dense fabric are strengths in particular application domains. Improved LUT-tree-optimized logic synthesis and constraint-driven place and route are required to increase its competitiveness.