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From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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Date: Tue, 27 Sep 2005 09:31:31 +1000
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Cc: linuxppc64-dev@ozlabs.org, Stephen Rothwell <sfr@canb.auug.org.au>,
	linuxppc-dev@ozlabs.org
Subject: Re: [PATCH] powerpc: merged asm/cputable.h
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> > There is a small issue here: You turn identify_cpu into C code. However,
> > on ppc32, this is called with the kernel not yet relocated (before
> > prom_init even !). Same with the feature fixup. On ppc32, in order to
> > run C code that early, it needs to be in -mrelocatable bits of code
> > (like prom_init) or use RELOC macros (ugh !).
> 
> We could keep the bulk of the patch (turn cur_cpu_spec into a struct) but 
> still do identify_cpu() in asm, although it would seem like a step backward.

We can do it in C in ppc32 if we use proper RELOC() macros, or do it in
an -mrelocatable piece of code like prom_init (but I'd like to avoid
that).

> Do people think it's "better" to have one unified asm implementation, or one 
> in asm for ppc32 and one in C for ppc64?

We should only need one implementation for both I suppose.

Ben