> The correct algorithm, which is implemented in the posted patch is:
>
> 1. if has cpuid
> do cpuid
> else
> probe 486/386
> if !386 && flags are preserved across divison
> attempt enabling cpuid (do the dangerous 0x22,0x23 port stuff)
> goto 1
> end if
> end if
> 2. if vendor == Cyrix
> do cyrix DEVID detection stuff (more 0x22,0x23 stuff)
> end if
>
> This way, there no way of misdetecting a Pentium II for a Cyrix and play
> around with the BX ports.
Ah! So it's the Pentium II that "emulates" the Cyrix div behaviour...
> Since all Pentium II and MMX *have* cpuid.
> Cyrixes with the cpuid off by default get a second round at the cpuid
> code. Once we have cpuid all is well, since Cyrix specific code can be
> trivially excluded. I believe the patch to be quite ingenious and correct.
This is correct.
Mike
-- .----------------------------------------------------------------------. | Mike Jagdis | Internet: mailto:mike@roan.co.uk | | Roan Technology Ltd. | | | 54A Peach Street, Wokingham | Telephone: +44 118 989 0403 | | RG40 1XG, ENGLAND | Fax: +44 118 989 1195 | `----------------------------------------------------------------------'
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