I was reading about the MathStar FPOA devices and I started thinking about parallels between the architectural advances in CPUs compared to FPGAs. With the increases in speed with process refinements dropping off in the current technologies, CPU makers have taken advantage of the increased density to provide multiple CPUs rather than continually increasing the clock rates.
FPGAs on the other hand, continue to increase density by making larger versions of the same chips and trying to push speed as they go. The only exception to this is the way they have incorporated functions on the chip that are not the basic building blocks. I believe it started with memory blocks. Then multipliers were added. Now there are a number of different dedicated functional blocks that are available on the high end FPGA devices.
So where is this headed now? My understanding is that the FPOA was a rather coarse grained architecture. I also have the impression that the company is not succeeding because of software issues, not any inherent lacking in the devices or the architecture. In fact, from what I have read, a coarse grained architecture can provide a lot faster processing and higher density than can a fine grained one making the silicon cost a lot lower.
With the cost of gates dropping to such low levels, does it really make sense to continue to provide fine grained devices which use so much of the device for routing? I don't remember who first told me, "We sell you the routing and throw in the logic for free!" A coarse grained architecture should require much less of the programmable routing giving you much more of the "free" logic.
It seems like the current FPGA devices are heading in the coarse grained direction. They just haven't cut the umbilical cord yet. Most likely because that cord is rooted in the old software. A coarse grained architecture would need a doctor's slap on the behind for the birth of new design tools.
So, are coarse grained architectures the way of FPGA... opps FPxA devices in the near future? Will the lowly LUT and FF be pushed into the dark corners of the die in coming years? I think it is not a matter of if, just a matter of when and I think the when is soon!