Re: [RFC PATCH 2/5] hw/arm/smmuv3: Add initial support for SMMUv3 Nested device

[Nicolin Chen <nicolinc@nvidia.com>]

On Thu, Nov 14, 2024 at 08:20:08AM +0000, Shameerali Kolothum Thodi wrote:
> > > diff --git a/include/hw/arm/virt.h b/include/hw/arm/virt.h index
> > > 46f48fe561..50e47a4ef3 100644
> > > --- a/include/hw/arm/virt.h
> > > +++ b/include/hw/arm/virt.h
> > > @@ -50,6 +50,9 @@
> > >  /* MMIO region size for SMMUv3 */
> > >  #define SMMU_IO_LEN 0x20000
> > >
> > > +/* Max supported nested SMMUv3 */
> > > +#define MAX_SMMU_NESTED 128
> > Ouch, that many?!
> 
> 😊. I just came up with the max we can support the allocated MMIO space.
> We do have systems at present which has 8 physical SMMUv3s at the moment.
> Probably 16/32 would be a better number I guess.

FWIW, we have systems having 20 physical SMMUs at this moment :)

Thanks
Nicolin