Re: [Qemu-devel] [PATCH 2/3] arm_gic: SGIs for GICD_ICFGR are WI

[Adam Lackorzynski <adam@os.inf.tu-dresden.de>]

On Fri Aug 15, 2014 at 14:12:17 +0200, Christoffer Dall wrote:
> On Sun, Aug 03, 2014 at 10:53:46AM +0200, Adam Lackorzynski wrote:
> > Writes to SGIs for GICD_ICFGR register must be ignored.
> > 
> > Signed-off-by: Adam Lackorzynski <adam@os.inf.tu-dresden.de>
> > ---
> >  hw/intc/arm_gic.c | 11 +++++++----
> >  1 file changed, 7 insertions(+), 4 deletions(-)
> > 
> > diff --git a/hw/intc/arm_gic.c b/hw/intc/arm_gic.c
> > index d2b1aaf..cd6e6ea 100644
> > --- a/hw/intc/arm_gic.c
> > +++ b/hw/intc/arm_gic.c
> > @@ -566,10 +566,13 @@ static void gic_dist_writeb(void *opaque, hwaddr offset,
> >              } else {
> >                  GIC_CLEAR_MODEL(irq + i);
> >              }
> > -            if (value & (2 << (i * 2))) {
> > -                GIC_SET_EDGE_TRIGGER(irq + i);
> > -            } else {
> > -                GIC_CLEAR_EDGE_TRIGGER(irq + i);
> > +            /* SGIs are WI */
> > +            if (irq >= 16) {
> > +                if (value & (2 << (i * 2))) {
> > +                    GIC_SET_EDGE_TRIGGER(irq + i);
> > +                } else {
> > +                    GIC_CLEAR_EDGE_TRIGGER(irq + i);
> > +                }
> >              }
> >          }
> >      } else if (offset < 0xf10) {
> 
> Actually, this looks a bit weird given that you do set the model bit,
> which should probably be treated as WI/RAZ for a GICv2 emulation, but
> you don't set the edge trigger bit for them.

I've addressed that in a separate patch now. However, I'm not sure got
the revision check right. Comments appreciated!

> I think a cleaner fix might be to to just change the existing check from
> (irq < GIC_INTERNAL) to (irq < GIT_NR_SGIS), then you also don't need
> the next patch.

Ok, new series sent out.



Adam
-- 
Adam                 adam@os.inf.tu-dresden.de
  Lackorzynski         http://os.inf.tu-dresden.de/~adam/