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Date:   Thu, 10 Aug 2023 15:34:49 +0100
From:   Will Deacon <will@kernel.org>
To:     Michael Shavit <mshavit@google.com>
Cc:     iommu@lists.linux.dev, linux-arm-kernel@lists.infradead.org,
        linux-kernel@vger.kernel.org, robin.murphy@arm.com,
        nicolinc@nvidia.com, jgg@nvidia.com, jean-philippe@linaro.org
Subject: Re: [PATCH v5 6/9] iommu/arm-smmu-v3: Move CD table to
 arm_smmu_master
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On Thu, Aug 10, 2023 at 05:45:03PM +0800, Michael Shavit wrote:
> On Wed, Aug 9, 2023 at 9:50 PM Will Deacon <will@kernel.org> wrote:
> >
> > On Wed, Aug 09, 2023 at 01:12:02AM +0800, Michael Shavit wrote:
> > > @@ -2203,7 +2186,7 @@ static int arm_smmu_domain_finalise(struct iommu_domain *domain,
> > >               ias = min_t(unsigned long, ias, VA_BITS);
> > >               oas = smmu->ias;
> > >               fmt = ARM_64_LPAE_S1;
> > > -             finalise_stage_fn = arm_smmu_domain_finalise_s1;
> > > +             finalise_stage_fn = arm_smmu_domain_finalise_cd;
> >
> > Why is this a better name? Now we have inconsistency with
> > arm_smmu_domain_finalise_s2().
> 
> There was a time where s1cfg represented the entire STE and carried
> the entire cd table. We've gotten rid of s1cfg, and now only store
> arm_smmu_ctx_desc in the arm_smmu_domain for stage 1 domains.
> arm_smmu_domain_finalise_cd is IMO more clear, especially given the
> historical baggage around `s1`.

Ok, but it's the inconsistency I object to. I don't think it's clear at
all to have arm_smmu_domain_finalise_cd() and arm_smmu_domain_finalise_s2().

The easiest thing is to leave it as-is.

Will