bad pmd

[Russell King - ARM Linux]

On Tue, Dec 07, 2010 at 12:26:45PM -0500, Aric D. Blumer wrote:
> Matt Reimer and I believe we have found what is going on here.  I've put
> in a fix (no failures yet), but I wanted to bounce it off anyone interested.
> 
> The PXA platform does not use the "bad pmd" mapping that Russell
> describes above under normal circumstances, but the PXA resume code
> (arch/arm/mach-pxa/sleep.S) does on resume:

Good find.

> I'm using the patch below as a fix for now, but it's hard to know what
> registers are available.  Might be better to just mask it off the lower
> bits in r1 again.
> 
>         @ Let us ensure we jump to resume_after_mmu only when the mcr above
>         @ actually took effect.  They call it the "cpwait" operation.
> -       mrc     p15, 0, r1, c2, c0, 0           @ queue a dependency on CP15
> -       sub     pc, r2, r1, lsr #32             @ jump to virtual addr
> +       mrc     p15, 0, r0, c2, c0, 0           @ queue a dependency on CP15
> +       sub     pc, r2, r0, lsr #32             @ jump to virtual addr

I don't see anything wrong with this.  Any PXA people want to ack this?