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SubjectRe: Enabling L2 cache for overdrive CPUs.
davej@codemonkey.org.uk writes:
> Some CPU overdrives (such as those made by powerleap) mean
> that we get a CPU with L2 cache disabled by default, and
> a BIOS that doesn't know how to turn it on.
> The patch below is untested, and I'd like some feedback
> from folks (preferably those with these wacky overdrives,
> but also from regular intel CPUs too - disable L2 in your
> bios and try booting with 'enable-l2' and see what happens).
...
> + cr0 = read_cr0();
> + cr0 |= 1<<30;
> + write_cr0 (cr0);
> +
> + rdmsr (0x11e, lo, hi);
> + lo |= 0x40101;
> + wrmsr (0x11e, lo, hi);
> +
> + cr0 &= ~(1<<30);
> + write_cr0 (cr0);
> +
> + wbinvd();

Ugh. Is this for the PII overdrive for PPro socket or what?

Seems awfully dangerous to have a __setup() clobber MSRs without
checking the cpuid first.
Shouldn't this be in the CPU detection/quirks code instead?
It already contains stuff similar to this.

/Mikael
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