Re: [PATCH] Display Intel Dynamic Acceleration feature in /proc/cpuinfo

Alan Cox
2007-05-24T23:46:32Z

On Thu, 24 May 2007 18:41:54 -0400
Dave Jones <davej@redhat.com> wrote:

> On Thu, May 24, 2007 at 03:14:39PM -0700, H. Peter Anvin wrote:
>
> > pbe collides with abuse by at least two vendors (AMD and
> > Cyrix/Centaur/VIA) of this bit for 3DNow.
>
> Unless I'm mistaken,
>
> pbe comes from cpuid level 1
>
> 3dnow comes from cpuid level 0x80000001
> though I did notice that amd have it in edx, whilst via have it in ecx
> curiously.

The older AMD docs (CPU rev guide) list bit 31 of both 0x80000001 and
0x00000001 as 3dnow

All their example code/docs say to use 0x80000001