On Mon, Feb 10, 2025 at 2:44 PM Alyssa Rosenzweig <alyssa@rosenzweig.io> wrote:
>
> Some DARTs on Apple SoCs are "locked" at boot time, meaning we cannot
> write most of their configuration registers. Currently, we refuse to
> probe locked DARTs and do not include any in the upstream device trees.
> However, the DARTs used for the display controller are locked, so we
> need to handle locked DARTs as a prerequisite for a KMS driver.
>
> This series teaches the iommu/apple-dart driver about locked DARTs,
> preparing for a future upstream display driver. It has been extensively
> tested downstream with our work-in-progress display driver.
>
> Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
> ---
> Alyssa Rosenzweig (5):
>       iommu/dart: Track if the DART is locked
>       iommu/dart: Skip reset for locked DARTs
>       iommu/dart: Set DMA domain for locked DARTs
>       iommu/dart: Reject identity domain for locked DARTs
>       iommu/dart: Assert !locked when configuring
>
>  drivers/iommu/apple-dart.c | 47 +++++++++++++++++++++++++++++++---------------
>  1 file changed, 32 insertions(+), 15 deletions(-)
> ---
> base-commit: 2014c95afecee3e76ca4a56956a936e23283f05b
> change-id: 20250210-locked-dart-d7ece05f19a8
>
> Best regards,
> --
> Alyssa Rosenzweig <alyssa@rosenzweig.io>
>
>

Series LGTM, having looked over this many times as part of kernel
maintenance for Fedora Asahi Remix.

Reviewed-by: Neal Gompa <neal@gompa.dev>


-- 
真実はいつも一つ！/ Always, there's only one truth!