intel/isl: Support CCS on Ys-tiled images
Why this is beneficial
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Removes a blocker towards enabling HiZ+CCS fast clears in more mipmapped cases (#5258).
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Potentially helps enable CCS for 3D, 64bpp+ surfaces on ACM+.
ISL may have an overly conservative implementation of a restriction in BSpec 44930:
Compression of 3D Ys surfaces with 64 or 128 bpp is not supported in Gen12.
The implementation disables CCS on both gfx12.0 and gfx12.5 (even though the latter uses Tile64 instead of Ys). With CCS enabled on Ys images, we can run an experiment to see if dropping ISL's restriction causes CTS tests to fail on gfx12.0 but not on gfx12.5. That would provide a datapoint in support of dropping the restriction for gfx12.5.
How we can implement this
@llandwerlin started the effort in !23620 (merged), but we ultimately simplified the MR to exclude support for it. We may want to pick things up from there, but first I think blocking this issue on the CCS redesign that comes with #10740 is a good idea in order to avoid any complications with ISL_TILING_GFX12_CCS
(which assumes the main surface is Y0-tiled).