[PATCH] ppc32: make sure we have an L3 before touch its control register

Benjamin Herrenschmidt benh at kernel.crashing.org
Fri Oct 7 10:33:49 EST 2005


On Fri, 2005-10-07 at 10:26 +1000, Benjamin Herrenschmidt wrote:
> > Dope, you're right.  I notice that we apparent do this for BTIC and  
> > DPM in this function though?
> 
> Yes, those bits are buggy. Good catch

And no, in fact, my brain is buggy... On ppc32 we identify first, then
fixup, then only do the call_setup_cpu ! That's why the Idle NAP code
actually goes test the feature bit.

I think ppc64 does it the other way around. ppc64 certainly _requires_
taht the fixup has not yet been applied while running early_setup() as
it may change some CPU features according to firmware properties.

So in the merged kernel, we need to be extra careful here. I think we
should go the ppc64 way actually and apply the fixups later. But that
means fixing the code in cpu_setup_6xx.S indeed.

Ben.





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