[PATCH 4/6] ARM: reset: add reset functionality for jumping to a physical address

[Will Deacon]

On Wed, Jun 08, 2011 at 04:55:11PM +0100, Frank Hofmann wrote:
> 
> 
> On Tue, 7 Jun 2011, Frank Hofmann wrote:
> 
> >
> >
> > On Tue, 7 Jun 2011, Dave Martin wrote:
> [ ... ]
> >> How about:
> >>
> >> 	typeof(cpu_reset) *phys_reset =
> >> 		(typeof(cpu_reset) *)virt_to_phys(cpu_reset);
> >
> > Function pointers ;-)
> > Thanks.
> 
> Hmmm ...
> 
> Just found a problem with this.
> 
> If you have a MULTI_CPU config, this doesn't compile. For two reasons:
> 
> 1. you cannot use cpu_reset as argument to virt_to_phys because you can't
>     take the address
>     That bit can be fixed by changing the MULTI_CPU #define in
>     <asm/proc-fns.h> not to include the macro argument.
>     (There is no code in the arm tree using cpu_reset_whatever names which
>     would break from that change ... still, not that nice)
> 
> 2. even when you do that, you loose the "typeof()" information and the
>     above still doesn't compile.
> 
> Only a manual type override,
> 
>  	void (*phys_reset)(unsigned long) = (void (*)(unsigned long))cpu_reset;
> 
> is accepted then.

Damn, yes, I assumed the MULTI_CPU case would just pointer at the structure field,
but it takes the argument as parameter for the invocation. Oh well, I'll hardcode
the type after all then!

I'll send a v2 once I've finished cleaning up the code as I've tried to make it
more useful following on from your earlier feedback.

Cheers,

Will