> > : I am also upgrading my computer to 6x86. I've read that Linux
> > : works on 6x86 perfectly, doesn't it? So, why bother detecting the
> > : CPU?
> > It does have some points to have the kernel recognize it. As it
> > claims, Cyrix 6x86 should support MMX codes.
> 'Fraid not. Cyrix's M2 chip (in development) is supposed to support MMX
> extensions, but the currently shipping 6x86 does not.
> > If, possibly in the future, some programs need to detect for the
> > CPUID in order to turn the functions on, will it be a bug to regard
> > it as 4x86? 6x86 is actually different from a Intel's Pent...
> I honestly don't know if the Linux kernel could currently use any 6x86-specific
> features if it knew it was running on a 6x86. I do know that the 6x86 handles
> code optimized for the 486 better than it handles code optimized for the Pentium
> (I tried compiling kernel 2.0.7 with each optimization, and the BogoMips value
> was halved when going from 486 to Pentium optimizations, if that means
The 6x86 has pentium sized pages (4MB) or 486 size pages (4K ?), it also
Cyrix sized pages (apparently varible sized between 4K and 4M ?).
I would think the that the kernel would be at an advantage if it used
pentium sized pages ( and maybe still the 486 optimizations?).
The 6x86 can also finish instructions out-of-order. So can the pentium
there are region registers that you can disable this for specific
both the PentiumPro and the 6x86 [like a Memory-mapped IO card]. I
presume that using this feature would also be advantageous (sp?) to the
My motherboard BIOS correctly recognizes the CPU as a Cyrix-6x86 P166+
, and I also
think it probably disables some of these features. Sooo, I am looking
making the linux kernel recognize the 6x86 and use the best mix of
features of it.