I'm not quite sure I follow. Are you suggesting that pre-programmed FGPAs will start appearing in mainstream PCs or game consoles, with no way to modify their programming. That doesn't make any sense. ASICs are much cheaper (per unit) and much faster.

If you're thinking about a specific application, that can make use of an FPGA, then you first have to identify functions that actually benefit from the FPGA. The CPU is going to be much faster in general purpose computing. The FPGAs really shine in highly parallel task, but even then GPUs are faster, if applicable to the task. Then there's the development cost. You won't be just writing a piece of code and then deciding if it's going to the FPGA or the CPU, the code has to be written separately for both. I suggest you do some coding first to get a feel for it and then start sorting the problem out.

As to how hard it's going to be. With your experience, I'd say pretty hard. If you're going to write the FPGA code in Verilog or VHDL, it's quite different from anything you've ever seen. Plus, optimization is everything, so you need to get an understanding of what the HDL compiler does.

Quote: Original post by Splinter of Chaos
Should have asked if there's anything I can do to prepare myself. Like, what subject to study. Kind of actually reminds me of calculator programming, except that was a weak, but high level language.

Well, you can start programming in Verilog or VHDL right away. Personally I find Verilog to be somewhat easier. Read some Verilog/VHDL tutorials (Here's one), get a simulator (e.g. Icarus Verilog) and start coding. Keep in mind though, that the simulators are event based, while on a FPGA the programs actually are made up of a circuit consisting of a large number of elementary logic blocks working simultaneously. This means that there are slight semantic differences between programs run in a simulator and on an FPGA. Also it helps if you have an understanding of basic digital electronics.

Quote:
Also:
As you pointed out, FPGAs are slower than more specialized pieces of equipment, but they're flexible and field programmable. So, one of the first questions, and this is really just a clarification, was, what is their likely use in games? I have to imagine it'll be something a little more complex than just taking foo() and doing it there instead of on RAM. It seems to me like they'd be really good at keeping track of threads and runtime-data (like execution time, number of times code block was used, etc.). Yes? Or would this, or IS that, or will, be done by a specialized piece of instead?

To be quite honest, I cannot imagine any use for FPGAs in games programming as such. You could perhaps use one for physics simulation, but GPUs are getting more and more generalized and physics hardware might become mainstream, so they seem better suited for the task. Maybe some AI tasks might benefit from an FPGA. Or you could use it as an accelerator for some audio/video handling, like performing parts of MP3 decoding.

An FPGA really would not be good for handling system data, such as threads. In a PC, the FPGA would likely be connected to the PCI bus, where it has direct access to the system memory, acting much like a co-processor of sorts. The first obstacle in even accessing system data is to deal with the logical to physical memory mapping done in the CPU.

The way you would use the FPGA is that you prepare a piece of data in RAM for the FPGA to process using the CPU, then you pass the FPGA the physical address to that data (or you write the data into a specific address known by the FPGA), let the FPGA run with it and read the results from another part of the memory. Before any of that though, the FPGA has to be programmed by feeding it a stream of bits, the output of the HDL compiler. This takes time (might take as much as a whole second, not including the compilation), so reprogramming the FPGA frequently on the fly isn't really an option.

Quote: Original post by Talroth
2 years ago at an APICS conference I attended there was a group doing research with FPGAs, and looking at their applications to mainstream computers. One of the biggest problems they had was the highly limited write count they offered. Like flash memory, FPGAs eventually stop being reprogrammable.

They must have been using flash based FPGAs. I don't see any reason not to use RAM based FPGAs in a PC setting and use the CPU to program them after power-up.