Why another Routing Fabric? Why should FPGA vendors adopt it?
- What are the issues with prevailing FPGA fabrics?
- Prevailing FPGA devices have forever been extremely area inefficient. They are based on 2D-Mesh Network with N^2 crosspoint complexity.
- 2D-Mesh based FPGAs use ~75% die area for fabric.
- Is there an alternative fabric?
- Multi-stage based networks with N*log N crosspoint complexity are known since the invention of automatic telephone switching.
- However, so far, no practical layouts for Multi-stage networks are known to be usable as FPGA Fabrics.
- How hard is it to sell Multi-stage networks as FPGA Fabric?
- Since the invention of FPGA, no one found out viable and elegant layout for multi-stage network based fabric that compete with 2D-Mesh Fabrics in every dimension.
- FPGA Fabric architects/designers, in general, have no understanding of multi-stage networks
- Previous failed multi-stage Fabric attempts did not solve the problem as elegantly in every dimension.
- Furthermore previous failed attempts to use multi-stage networks made FPGA Fabric designers even more suspicious of them.