Re: [PATCH v5 2/9] iommu/arm-smmu-v3: Replace s1_cfg with cdtab_cfg

From: Michael Shavit
Date: Thu Aug 10 2023 - 13:15:55 EST


> > > What dead code? Is the deal here that we keep the field, but still
> > > infer the value to write from (cd_table->l1_desc == null) in
> > > arm_smmu_write_strtab_ent??
> >
> > Keep the field and write it directly when populating the ste (i.e. don't
> > infer anything), but the field moves into 'struct arm_smmu_ctx_desc_cfg'.
>
> Yes - the 'dead code' is that we introduce storage for a field that is
> always a known constant (STRTAB_STE_0_S1FMT_64K_L2).

I'm not sure we're on the same page here. s1fmt could contain either
`STRTAB_STE_0_S1FMT_64K_L2` or `STRTAB_STE_0_S1FMT_LINEAR`, and this
value will be directly copied in arm_smmu_write_strtab_ent.