anv: Rework CCS memory handling on TGL-LP
The previous way we were attempting to handle AUX tables on TGL-LP was
very GL-like. We used the same aux table management code that's shared
with iris and we updated the table on image create/destroy. The problem
with this is that Vulkan allows multiple VkImage objects to be bound to
the same memory location simultaneously and the app can ping-pong back
and forth between them in the same command buffer. Because the AUX
table contains format-specific data, we cannot support this ping-pong
behavior with only CPU updates of the AUX table.
The new mechanism switches things around a bit and instead makes the aux
data part of the BO. At BO creation time, a bit of space is appended to
the end of the BO for AUX data and the AUX table is updated in bulk for
the entire BO. The problem here, of course, is that we can't insert the
format-specific data into the AUX table at BO create time.
Fortunately, Vulkan has a requirement that every TILING_OPTIMAL image
must be initialized prior to use by transitioning the image from
VK_IMAGE_LAYOUT_UNDEFINED to something else. When doing the above
described ping-pong behavior, the app has to do such an initialization
transition every time it corrupts the underlying memory of the VkImage
by using it as something else. We can hook into this initialization and
use it to update the AUX-TT entries from the command streamer. This way
the AUX table gets its format information, apps get aliasing support,
and everyone is happy.
One side-effect of this is that we disallow CCS on shared buffers.
We'll need to fix this for modifiers on the scanout path but that's a
task for another patch. We should be able to do it with dedicated
allocations.
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>
Tested-by: Marge Bot <https://gitlab.freedesktop.org/mesa/mesa/merge_requests/3519>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/merge_requests/3519>
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