[rescue] Indy CPU upgrade

[Francisco Javier Mesa-Martinez]

> I don't believe R4600 is newer than R4400.   I seem to remember them
> coming out at the same time on the Indy.  The only real difference is
> that the R4400 is optimized for floating-point operations, and the R4600
> is optimized for integer operations.

R4600 is worse than R4400 in both Int and FP. The R4600 was optimized for
"low cost" :). The R4400 had a little bit more smarts to it, plus it had support
for SMP on chip. The R4600 didn't... The R4600 had a bit better cache
implementation, and I believe a shorter pipeline thant the R4400... So it
may have a bit of a performance improvement due to lower penalty when it
comes to stalls....

I believe that R4600 came with smaller caches 512K vs 1M for the R4400.