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Re: potential hack/workaround for cpuinfo not being setup early

On Sun, Aug 17, 2008 at 06:30:25AM +1000, matthew green wrote:
> i found this lying around in my tree.  can someone try it out and
> commit it if it is useful?

I think this is dangerous, as other parts of the kernel think they initialized
everything for all cpus, but actually didn't.

I was just looking at a real solution for this, and while it is not exactly
straightforward, I think I'm halfay through.

However, I do not have the slightest understanding of pre-v9 MMUs, so I can
only rearange the code to do as close as possible as the old code. I ran
into a significant difference from the (much more simple) sparc64 code:

The cpu infos are not only page aligned, but cache congruent to the fixed
CPUINFO_VA. On sparc64 this is not done, but we map the CPUINFO_VA view
of the page uncached (and wonder off into the real VA imediately if not
in assembler code - long term I'd like to get rid of the whole fixed mapping
and use %g7 for curcpu() instead).

So stupid question: wouldn't it be possible to do the CPUINFO_VA page
uncached on sparc too? This would greatly simplify the code I'm adding to
pmap_bootstrap. Am I missing something?


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