From mboxrd@z Thu Jan  1 00:00:00 1970
From: linux@arm.linux.org.uk (Russell King - ARM Linux)
Date: Mon, 7 Feb 2011 14:33:51 +0000
Subject: [PATCH v3 2/5] ARM: pm: add generic CPU suspend/resume support
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On Mon, Feb 07, 2011 at 04:27:34PM +0200, saeed bishara wrote:
> > As I've said, there's not much other choice here. ?We _have_ to have an
> > identity mapping in place to bring the MMU back online, or we'll crash.
> > That's non-optional. ?So if this is a problem for cpuidle, cpuidle needs
> > to ensure that a page table switch has happened prior to the CPU going
> > down which _can_ be safely modified.
> I fully agree with you, but what I was suggesting is to create
> temporary identity page table at boot time, the resume code will load
> that page table (Context ID will be loaded with unique ASID), enable
> mmu, then the original page table and Context ID will be restored.

That's much easier to do in C code than in the assembly code.  Let's
keep the assembly code as simple as possible...