[RFC PATCH v2 3/5] ARM: kernel: update cpu_suspend code to use cache LoUIS operations

[Lorenzo Pieralisi]

On Tue, Dec 11, 2012 at 11:27:39PM +0000, Stephen Boyd wrote:
> On 12/11/12 08:38, Will Deacon wrote:
> > diff --git a/arch/arm/mm/cache-v7.S b/arch/arm/mm/cache-v7.S
> > index cd95664..f58248f 100644
> > --- a/arch/arm/mm/cache-v7.S
> > +++ b/arch/arm/mm/cache-v7.S
> > @@ -44,7 +44,8 @@ ENDPROC(v7_flush_icache_all)
> >  ENTRY(v7_flush_dcache_louis)
> >         dmb                                     @ ensure ordering with previous memory accesses
> >         mrc     p15, 1, r0, c0, c0, 1           @ read clidr, r0 = clidr
> > -       ands    r3, r0, #0xe00000               @ extract LoUIS from clidr
> > +       ALT_SMP(ands    r3, r0, #(7 << 21))     @ extract LoUIS from clidr
> > +       ALT_UP(ands     r3, r0, #(7 << 27))     @ extract LoUU from clidr
> >         mov     r3, r3, lsr #20                 @ r3 = LoUIS * 2
> 
> You need to fix this mov as well, right?

And after doing that I think the suspend finisher will still have
to call flush_cache_all() since LoUU == 1 on A8, L2 is not cleaned
and that's probably what we want if it can be retained.

What about this (compile tested) ?

Lorenzo

--->8

diff --git a/arch/arm/mm/cache-v7.S b/arch/arm/mm/cache-v7.S
index cd95664..036f80f 100644
--- a/arch/arm/mm/cache-v7.S
+++ b/arch/arm/mm/cache-v7.S
@@ -44,8 +44,9 @@ ENDPROC(v7_flush_icache_all)
 ENTRY(v7_flush_dcache_louis)
 	dmb					@ ensure ordering with previous memory accesses
 	mrc	p15, 1, r0, c0, c0, 1		@ read clidr, r0 = clidr
-	ands	r3, r0, #0xe00000		@ extract LoUIS from clidr
-	mov	r3, r3, lsr #20			@ r3 = LoUIS * 2
+	ALT_SMP(lsr	r3, r0, #20)		@ r3 = clidr[31:20]
+	ALT_UP(lsr	r3, r0, #26)		@ r3 = clidr[31:26]
+	ands	r3, r3, #0xe			@ r3 = LoUIS/LoUU * 2
 	moveq	pc, lr				@ return if level == 0
 	mov	r10, #0				@ r10 (starting level) = 0
 	b	flush_levels			@ start flushing cache levels