v3dv/descriptor_set: support for immutable samplers
They are bound at the set layout, and cannot be changed. From
VkDescriptorSetLayoutBinding spec:
"pImmutableSamplers affects initialization of samplers. If
descriptorType specifies a VK_DESCRIPTOR_TYPE_SAMPLER or
VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER type descriptor, then
pImmutableSamplers can be used to initialize a set of immutable
samplers. Immutable samplers are permanently bound into the set
layout and must not be changed; updating a
VK_DESCRIPTOR_TYPE_SAMPLER descriptor with immutable samplers is
not allowed and updates to a
VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER descriptor with immutable
samplers does not modify the samplers (the image views are updated,
but the sampler updates are ignored)"
We stored them as part of the set layout. It also means that when we
need the sampler (like for texture operations) we can't just ask for a
descriptor, as it would not have the sampler. A new method is created.
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/6766>
3 files changed
