Xilinx / finn

Dataflow compiler for QNN inference on FPGAs
https://xilinx.github.io/finn
BSD 3-Clause "New" or "Revised" License
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4-BIT DSP-MVU: Allow very wide lanes requiring even a high-lane extension. #1203

Open preusser opened 2 months ago

preusser commented 2 months ago

This PR removes the assumption that the leftmost lane of a low-precision soft vector compute on the wide DSP datapath would. The design now also generates a high lane extension for the leftmost lane in the fabric as needed. Additionally, the cross-SIMD reduction in an adder tree is now pipelined so as to reduce the challenge for timing closure in high-fanin designs.