Fxsave/Fxrstor on Pentium II

[Slasher]

Hi, I was trying to add FPU/MMX/SSE register saving to my kernel.
Initially I used the Fxsave/Fxrstor commands.
In Bochs this works but on my Pentium II, it does not.
I've used CPUID to check if Fxsave/Fxrstor comands are supported.
Bochs supports it but Pentium II does NOT! it only has MMX
My question is, was the Fxsave/Fxrstor commands introduced after Pentium II (when SSE was introduced) and from which processor will they be present?
Thanks

[FlashBurn]

When I?m remembering right they were supported from the 100MHz FSB PII?s. So I think that you use a PII with 66MHz FSB! Take a look at www.sandpile.org.

[Slasher]

I found a link in Google groups that states Fxsave/Fxrstor works on 333Mhz Pentium II onwards.

Can anyone confirm this?
[url=http://groups-beta.google.com/group/fido7.pvt.hardw.pc.x86.cpu/browse_thread/thread/b9df13f366223382/4a0adf9d227e760b?lnk=st&q=fxsave+pentium+II&rnum=4&hl=en#4a0adf9d227e760b] Google groups link
[/url]

[AR]

Okay, I've looked up the instructions and as far as I can see FXSAVE/FXRSTR were added for SSE, CPUs that don't have SSE will most likely only have FNSAVE/FNRSTR.

[Solar]

The "Basic Overview" volume 1 of the Intel CPU Manuals has an overview of which feature was introduced in which processor, IIRC.

[tom1000000]

Hi,

I remember checking this out and I thought it was all P2 400MHz and above.

Someone else said 333MHz.

Anyway I am 100% certain it was introduced before P3 / SSE.

Personally I am not supporting any CPU that doesn't have FXSAVE/FSRSTOR.