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Date:   Wed, 9 Aug 2023 13:26:41 -0300
From:   Jason Gunthorpe <jgg@nvidia.com>
To:     Will Deacon <will@kernel.org>
Cc:     Michael Shavit <mshavit@google.com>, iommu@lists.linux.dev,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        robin.murphy@arm.com, nicolinc@nvidia.com, jean-philippe@linaro.org
Subject: Re: [PATCH v5 2/9] iommu/arm-smmu-v3: Replace s1_cfg with cdtab_cfg
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On Wed, Aug 09, 2023 at 05:22:54PM +0100, Will Deacon wrote:

> > > If we want to use 4k leaf tables in some cases, how would you add
> > > that? Such a change shouldn't need the low-level strtab creation
> > > code to change.
> > 
> > You would modify arm_smmu_ctx_desc_cfg to teach it about the different
> > format. It would gain some (enum?) member that specifies the CD table
> > layout and geometry. arm_smmu_get_cd_ste() will interpret that member
> > and generate the correct STE for the specifc cd table.
> 
> Sounds a lot like the existing s1fmt field. Can we keep it?

If you are OK with the dead code, I don't object. But let's put it in
the struct arm_smmu_ctx_desc_cfg.

Jason