[PATCH] bsps/arm: fix off-by-1 in gicv3 processor count

[Gedare Bloom]

On Wed, Aug 4, 2021 at 11:18 AM Gedare Bloom <gedare at rtems.org> wrote:
>
> Hi Sebastian,
>
>
> On Wed, Aug 4, 2021 at 11:15 AM Gedare Bloom <gedare at rtems.org> wrote:
> >
> > ---
> >  bsps/shared/dev/irq/arm-gicv3.c | 4 ++--
> >  1 file changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/bsps/shared/dev/irq/arm-gicv3.c b/bsps/shared/dev/irq/arm-gicv3.c
> > index ea123d325e..95021f6ddf 100644
> > --- a/bsps/shared/dev/irq/arm-gicv3.c
> > +++ b/bsps/shared/dev/irq/arm-gicv3.c
> > @@ -551,11 +551,11 @@ uint32_t arm_gic_irq_processor_count(void)
> >      for (i = 0; i < CPU_MAXIMUM_PROCESSORS; ++i) {
> >        volatile gic_redist *redist = gicv3_get_redist(i);
> >
> > +      ++cpu_count;
> > +
> >        if ((redist->icrtyper & GIC_REDIST_ICRTYPER_LAST) != 0) {
> >          break;
> >        }
> > -
> > -      ++cpu_count;
> >      }
> Can you check my thinking here? I'm trying to implement SMP support
> for the versal on aarch64. The call to arm_gic_irq_processor_count()
> returns 1 through this code path. Since cpu_count is initialized to 0,
> I think we need to increment it each time we find an active processor,
> until we find the last active processor, which we also need to include
> in the count, because the cpu_count should be NUM_PROC + 1?
>
PS: the versal has 2 cores. thanks

> After I make this change, I encounter other problems with the
> secondary processor initialization, but at least it tries to
> initialize/wait for core#1 then.
>
> Thanks,
> Gedare
>
> >    }
> >
> > --
> > 2.25.1
> >