Messages in this thread | | | Subject | Re: What is the best way to identify a new x86 processor that does not implement the CPUID instruction? | From | Andi Kleen <> | Date | Fri, 08 Aug 2008 13:00:35 +0200 |
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"David Wilson" <mcs6502@gmail.com> writes:
> I recently bought a Norhtec MicroClient JrSX which uses the Vortex86sx > System on Chip processor (see http://vortex86sx.com/ for more > details). This is identified as a Cyrix 486SLC by the Linux kernel due > to the lack of a CPUID instruction. While this may be seen as a > cosmetic defect, if the kernel can identify the processor correctly it > could, for example, use the clock divisor code provided by the > manufacturer to slow down and speed up the CPU when required. > > The question is: how to differentiate this chip from the Cyrix part? > The freely available "brief data sheet" does not provide much detail. > > I have thought of a couple of schemes but am not really keen on either: > > 1) Clock speed - the SoC runs at 300+ MHz while the Cyrix part is < 100 MHz > 2) Look at the PCI VID/PID for the north bridge as this is part of the CPU die. > > Does anyone have any suggestions? Thanks.
I would suggest asking the CPU vendor. Surely they have some method. Then submit a patch to detect that CPU based on that method.
-Andi
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