Re: SMP possible with AMD CPUs?

[Johannes Erdfelt <johannes@erdfelt.com>]

On Thu, Aug 02, 2001, William T Wilson <fluffy@snurgle.org> wrote:
> On Wed, 1 Aug 2001, Johannes Erdfelt wrote:
> 
> > I don't know if this was true to begin with, but I know that SMP AMD
> > systems use the APIC SMP scheme Intel defined and uses.
> 
> Is this really true?  I seem to remember that there was very little
> difference between OPIC and APIC in the first place, but AMD could not use
> APIC because of licensing problems.
> 
> Since Athlons cannot use the same motherboards as Intel (unlike the K6-2)
> and AMD makes the SMP chipsets for Athlon, why would they possibly want to
> use APIC when they could more easily and cheaply use OPIC?

I'm pretty sure it's not identical since the APIC bus on GTL+ is most
likely different than the EV6 bus.

However, from a software point of view, they are pretty much identical
give or take a few implementation details (as seen in 2.2)

I don't know anything about OpenAPIC, so I can't say anything about the
similarities.

JE