[PATCH] drm/fourcc: Add Apple Interchange layout format modifier

[PATCH] drm/fourcc: Add Apple Interchange layout format modifier

[James Calligeros]

Apple Interchange is a tiled and compressed image layout used
for buffer exchange between Apple hardware blocks. It is
similar to the already-supported GPU_TILED_COMPRESSED layout.

Add a format modifier for Apple Interchange so that it can be
used for buffer exchange.

Signed-off-by: James Calligeros <jcalligeros99@gmail.com>
---
 include/uapi/drm/drm_fourcc.h | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/include/uapi/drm/drm_fourcc.h b/include/uapi/drm/drm_fourcc.h
index a103fdc0b3a3..aa51c116cd7d 100644
--- a/include/uapi/drm/drm_fourcc.h
+++ b/include/uapi/drm/drm_fourcc.h
@@ -1626,6 +1626,26 @@ drm_fourcc_canonicalize_nvidia_format_mod(__u64 modifier)
 #define DRM_FORMAT_MOD_APPLE_GPU_TILED fourcc_mod_code(APPLE, 1)
 #define DRM_FORMAT_MOD_APPLE_GPU_TILED_COMPRESSED fourcc_mod_code(APPLE, 2)
 
+/*
+ * Apple Interchange layout
+ *
+ * Apple Interchange is a compressed framebuffer format used exclusively for
+ * sharing buffers between hardware blocks (GPU, display controller, video
+ * codecs) on Apple platforms. It is similar to and uses the same compression
+ * scheme as GPU_TILED_COMPRESSED. There is no known uncompressed variant
+ * of Apple Interchange.
+ *
+ * Unlinke the GPU layouts, tile size is not dependent on bit depth. RGB
+ * images and the chroma components of YUV images use 16x16 tiles. The
+ * luma component of YUV images uses 32x32 tiles. Compression tiles
+ * are once again 16x16 with 8 bytes of metadata per compression subtile.
+ *
+ * AGX has limited support for Apple Interchange. It cannot be used for Z/S
+ * buffers or array images, for example. It is intended for scanout buffer
+ * sharing only.
+ */
+#define DRM_FORMAT_MOD_APPLE_INTERCHANGE fourcc_mod_code(APPLE, 3)
+
 /*
  * AMD modifiers
  *

---
base-commit: 08dbfad3f5040f5bdb6c529da20d6d4e81fefd72
change-id: 20260830-apple-interchange-modifier-cbcc311c835d

Best regards,
--  
James Calligeros <jcalligeros99@gmail.com>

Re: [PATCH] drm/fourcc: Add Apple Interchange layout format modifier

[sashiko-bot]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Low] Typo in the UAPI documentation comment for `DRM_FORMAT_MOD_APPLE_INTERCHANGE`: 'Unlinke' instead of 'Unlike'.
--

commit 8d891b8a7418ccf3a3ab6fe8fbc786ff834638af
Author: James Calligeros <jcalligeros99@gmail.com>

drm/fourcc: Add Apple Interchange layout format modifier

This commit introduces the DRM_FORMAT_MOD_APPLE_INTERCHANGE format modifier
for Apple platforms. It describes the format as a compressed framebuffer
layout used for sharing buffers between hardware blocks.

> diff --git a/include/uapi/drm/drm_fourcc.h b/include/uapi/drm/drm_fourcc.h
> index a103fdc0b3a36..aa51c116cd7dc 100644
> --- a/include/uapi/drm/drm_fourcc.h
> +++ b/include/uapi/drm/drm_fourcc.h
> @@ -1626,6 +1626,26 @@ drm_fourcc_canonicalize_nvidia_format_mod(__u64 modifier)
>  #define DRM_FORMAT_MOD_APPLE_GPU_TILED fourcc_mod_code(APPLE, 1)
>  #define DRM_FORMAT_MOD_APPLE_GPU_TILED_COMPRESSED fourcc_mod_code(APPLE, 2)
>  
> +/*
> + * Apple Interchange layout
> + *
> + * Apple Interchange is a compressed framebuffer format used exclusively for
> + * sharing buffers between hardware blocks (GPU, display controller, video
> + * codecs) on Apple platforms. It is similar to and uses the same compression
> + * scheme as GPU_TILED_COMPRESSED. There is no known uncompressed variant
> + * of Apple Interchange.
> + *
> + * Unlinke the GPU layouts, tile size is not dependent on bit depth. RGB

[Severity: Low]
This isn't a bug, but is this a typo (Unlinke instead of Unlike) in the newly
added UAPI documentation block?

> + * images and the chroma components of YUV images use 16x16 tiles. The
> + * luma component of YUV images uses 32x32 tiles. Compression tiles
> + * are once again 16x16 with 8 bytes of metadata per compression subtile.
> + *
> + * AGX has limited support for Apple Interchange. It cannot be used for Z/S
> + * buffers or array images, for example. It is intended for scanout buffer
> + * sharing only.
> + */
> +#define DRM_FORMAT_MOD_APPLE_INTERCHANGE fourcc_mod_code(APPLE, 3)

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260831-apple-interchange-modifier-v1-1-5d6e27f9f308@gmail.com?part=1