[PATCH v2 1/5] ARM: kernel: smp_setup_processor_id() updates

[Lorenzo Pieralisi]

On Fri, Nov 09, 2012 at 02:44:46PM +0000, Will Deacon wrote:
> On Fri, Nov 09, 2012 at 02:34:10PM +0000, Lorenzo Pieralisi wrote:
> > This patch applies some basic changes to the smp_setup_processor_id()
> > ARM implementation to make the code that builds cpu_logical_map more
> > uniform across the kernel.
> > 
> > The function now prints the full extent of the boot CPU MPIDR[23:0] and
> > initializes the cpu_logical_map for CPUs up to nr_cpu_ids.
> > 
> > Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi at arm.com>
> > ---
> >  arch/arm/kernel/setup.c | 7 ++++---
> >  1 file changed, 4 insertions(+), 3 deletions(-)
> > 
> > diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c
> > index da1d1aa..ede7c84 100644
> > --- a/arch/arm/kernel/setup.c
> > +++ b/arch/arm/kernel/setup.c
> > @@ -426,13 +426,14 @@ int __cpu_logical_map[NR_CPUS];
> >  void __init smp_setup_processor_id(void)
> >  {
> >  	int i;
> > -	u32 cpu = is_smp() ? read_cpuid_mpidr() & 0xff : 0;
> > +	u32 mpidr = read_cpuid_mpidr() & 0xffffff;
> 
> We need that is_smp() check, otherwise we'll go and do a funky CP15
> operation on CPU's that might not be too happy about it.

It is there :-) I just added a local variable for mpidr to avoid reading
it again later on when printing. The change moved the is_smp() check
one line down.

Thanks,
Lorenzo