[PATCH 3/3] ARM: vexpress: add support for CPU hotplug to ct-ca9x4 tile

[linux@arm.linux.org.uk (Russell King - ARM Linux)]

On Wed, Sep 08, 2010 at 05:46:02PM +0100, Will Deacon wrote:
> Hi Russell,
> 
> > On Tue, Aug 17, 2010 at 04:58:04PM +0100, Will Deacon wrote:
> > > The Versatile Express platform can support a quad-core Cortex-A9 tile running
> > > SMP Linux.
> > >
> > > This patch adds support for CPU hotplug when running in this configuration.
> > 
> > This ties the core tile support into the generic versatile express code,
> > something which the current code structure is careful to avoid.  Please
> > ensure that we continue to avoid making the generic code rely upon
> > CA9x4 code.
> 
> The cpu_{enter,leave}_lowpower functions are implemented in the tile code
> so they should be ok. I suppose the problem is that we might be able to do
> better than a WFI on some tiles. How about this?:

What I was referring to is that generic code _directly_ calls tile code.
That means if you want to build in support for two tiles, you're going
to have symbols clashing as two tiles will define functions called
'cpu_enter_lowpower' etc.