[PATCH 2/2] iommu/arm-smmu-v3: Override for Inst/Data attribute

Nicolin Chen nicolinc at nvidia.com
Fri Aug 7 09:43:52 PDT 2026


On Fri, Aug 07, 2026 at 03:37:37PM +0100, Peter Griffin wrote:
> Hi Nicolin,
> 
> Thank you for your review feedback.
> 
> On Fri, 24 Jul 2026 at 19:05, Nicolin Chen <nicolinc at nvidia.com> wrote:
> >
> > On Fri, Jul 24, 2026 at 01:39:43PM +0100, Peter Griffin wrote:
> > > @@ -1206,7 +1207,8 @@ void arm_smmu_get_ste_used(const __le64 *ent, __le64 *used_bits)
> > >                       cpu_to_le64(STRTAB_STE_1_S1DSS | STRTAB_STE_1_S1CIR |
> > >                                   STRTAB_STE_1_S1COR | STRTAB_STE_1_S1CSH |
> > >                                   STRTAB_STE_1_S1STALLD | STRTAB_STE_1_STRW |
> > > -                                 STRTAB_STE_1_EATS | STRTAB_STE_1_MEV);
> > > +                                 STRTAB_STE_1_EATS | STRTAB_STE_1_MEV |
> > > +                                 STRTAB_STE_1_INSTCFG);
> > >               used_bits[2] |= cpu_to_le64(STRTAB_STE_2_S2VMID);
> > >
> > >               /*
> > > @@ -1222,7 +1224,8 @@ void arm_smmu_get_ste_used(const __le64 *ent, __le64 *used_bits)
> > >       if (cfg & BIT(1)) {
> > >               used_bits[1] |=
> > >                       cpu_to_le64(STRTAB_STE_1_S2FWB | STRTAB_STE_1_EATS |
> > > -                                 STRTAB_STE_1_SHCFG | STRTAB_STE_1_MEV);
> > > +                                 STRTAB_STE_1_SHCFG | STRTAB_STE_1_MEV |
> > > +                                 STRTAB_STE_1_INSTCFG);
> > >               used_bits[2] |=
> > >                       cpu_to_le64(STRTAB_STE_2_S2VMID | STRTAB_STE_2_VTCR |
> > >                                   STRTAB_STE_2_S2AA64 | STRTAB_STE_2_S2ENDI |
> >
> > This adds for "stage-1" and "stage-2", while missing "bypass"?
> 
> I need to follow up again on this point, but I don't believe currently
> we require the override for Laguna when it's in bypass.

This get_ste_used lists all the critical fields that the HW will
read when operating in the mode per STE.Cfg.

Given that GBPA also has INSTCFG, STE.Cfg=Bypass uses it as well.

Nicolin



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