[Open-graphics] Sun releases RTL design for Niagra 2 under GPL 2.0

[Paul Brook]

> It is actually the FGX processor which would be of interest to us.  I
> have wondered if it would be possible to have a graphics processor based
> on multiple SIMD processors from standard MPUs.  I was thinking of the
> AltiVec; however, the SPARC is available free.

This has been disucussed here several times before. It isn't a viable option 
for two reasons:

a) Fixed function hardware is relatively easy to pipeline, and is smaller so 
we can fit more units in the same area. Variable function hardware (aka 
shaders) is more complicated and you generally need much higher clock and 
shorter pipelines, which aren't feasible to implement on current FPGAs.

b) 3D rendering is a very specialised task. Using a general purpose core adds 
lots of overhead for things that we just don't need. Even a relatively slow 
special-purpose FPGA can get much higher thoughput and better 
performance/watt than the fastest general purpose CPU.

Paul