Placement is one of the runtime bottlenecks in an FPGA design implementation flow, in which global placement accounts for a major portion of the runtime. In this paper, we demonstrate FPGA acceleration of wirelength gradient computation, which is an important part of modern analytical placement tools. To the best of our knowledge, this is the first work on acceleration of analytical placement on FPGAs. Our implementation uses OpenCL and leverages the FPGA's ability to support deep pipelines. We achieve an average speedup of 3.03x for wirelength gradient computation only and 2x for the entire global placement flow over a 28-threaded CPU implementation. Our placement quality is comparable to previously published works. Additionally, we can finish global placement for a design with 1 million cells and 1 million nets in less than 1 minute.