Platform numbers

Olof Johansson olof at
Sat Jul 9 02:52:35 EST 2005

On Fri, Jul 08, 2005 at 10:45:06PM +1000, Michael Ellerman wrote:
> Hi y'all,
> Are the platform numbers in asm-ppc64/processor.h private to Linux? Or do 
> firmware/hardware know about them?
> For pseries/pmac/maple it looks like we just assign them based on OF 
> properties. For iSeries we check in the naca. I don't see where BPA gets 
> assigned?
> The reason I ask is PLATFORM_MAPLE is currently 0x0500 which means we can't 
> (easily) do any bit mask based trickery on platform numbers.

They are just local to Linux and you can change them if you see a need
to. Only thing to think about is the LPAR bit (0x1).

Only challenge with going with bitmap is that the number of possible
platforms are quite a bit lower, I'm not sure how quickly that will hurt
us. We'll have other, bigger, headaches before we run out of platform
bits anyway.


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