[patch 1/2] arm: Disable outer (L2) cache in kexec

[Thomas Gleixner]

On Mon, 5 Jul 2010, Catalin Marinas wrote:

> On Mon, 2010-07-05 at 10:25 +0100, Thomas Gleixner wrote:
> > kexec does not disable the outer cache before disabling the inner
> > caches in cpu_proc_fin(). So L2 is enabled across the kexec jump. When
> > the new kernel enables chaches again, it randomly crashes.
> > 
> > Disabling L2 before calling cpu_proc_fin() cures the problem.
> > 
> > Disabling L2 requires the following new functions: flush_all(),
> > inv_all() and disable(). Add them to outer_cache_fns and call them
> > from the kexec code.
> > 
> > Signed-off-by: Thomas Gleixner <tglx at linutronix.de>
> > Index: linux-2.6/arch/arm/include/asm/outercache.h
> > ===================================================================
> > --- linux-2.6.orig/arch/arm/include/asm/outercache.h
> > +++ linux-2.6/arch/arm/include/asm/outercache.h
> > @@ -25,6 +25,9 @@ struct outer_cache_fns {
> >         void (*inv_range)(unsigned long, unsigned long);
> >         void (*clean_range)(unsigned long, unsigned long);
> >         void (*flush_range)(unsigned long, unsigned long);
> > +       void (*flush_all)(void);
> > +       void (*inv_all)(void);
> > +       void (*disable)(void);
> 
> Why don't we handle the flush_all/inv_all in the disable function and
> avoid exporting them? Once exported, people may start using them in

Because OMAP needs them to avoid reimplementing everything in the OMAP
part. So OMAP only needs to override the disable function. And if
Russell wants to add his cleanup patch which he posted last week, then
the split and the export needs to be done anyway.

Thanks,

	tglx