This modifier is primarily intended to be used by panvk to implement
sparse partially-resident images with better map and unmap
performance, and no worse access performance, compared to
implementing them in terms of U-interleaved.
With this modifier, the plane is divided into 64k byte 1:1 or 2:1
-sided tiles. The 64k tiles are laid out linearly. Each 64k tile
is divided into blocks of 16x16 texel blocks each, which themselves
are laid out linearly within a 64k tile. Then within each such
16x16 block, texel blocks are laid out according to U order,
similar to 16X16_BLOCK_U_INTERLEAVED.
Unlike 16X16_BLOCK_U_INTERLEAVED, the layout does not depend on
whether a format is compressed or not.
The hardware features corresponding to this modifier are available
starting with v10 (second gen Valhall.)
The corresponding panvk MR can be found at:
https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/38986
Previous version:
https://lists.freedesktop.org/archives/dri-devel/2026-January/547072.html
No changes since v2
Changes since v1:
* Rewrite the description of the modifier to be hopefully unambiguous.
Signed-off-by: Caterina Shablia <caterina.shablia@collabora.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Liviu Dudau <liviu.dudau@arm.com>
Link: https://patch.msgid.link/20260128184058.807213-1-caterina.shablia@collabora.com
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
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