[PATCH 10/27] iommu/arm-smmu-v3: Move the CD generation for SVA into a function

[Michael Shavit]

On Thu, Oct 12, 2023 at 7:26 AM Jason Gunthorpe <jgg at nvidia.com> wrote:
>
> Pull all the calculations for building the CD table entry for a mmu_struct
> into arm_smmu_make_sva_cd().
>
> Call it in the two places installing the SVA CD table entry.
>
> Open code the last caller of arm_smmu_update_ctx_desc_devices() and remove
> the function.
>
> Remove arm_smmu_write_ctx_desc() since all callers are gone.
>
> Remove quiet_cd since all users are gone, arm_smmu_make_sva_cd() creates
> the same value.
>
> The behavior of quiet_cd changes slightly, the old implementation edited
> the CD in place to set CTXDESC_CD_0_TCR_EPD0 assuming it was a SVA CD
> entry. This version generates a full CD entry with a 0 TTB0 and relies on
> arm_smmu_write_cd_entry() to install it hitlessly.
>

Is this change observable? AFAICT this will behave the same way but
with an extra CD sync operation to null TTB0 after setting EPD0.