drm/i915: use pat_index instead of cache_level

Currently the KMD is using enum i915_cache_level to set caching policy for
buffer objects. This is flaky because the PAT index which really controls
the caching behavior in PTE has far more levels than what's defined in the
enum. In addition, the PAT index is platform dependent, having to translate
between i915_cache_level and PAT index is not reliable, and makes the code
more complicated.

From UMD's perspective there is also a necessity to set caching policy for
performance fine tuning. It's much easier for the UMD to directly use PAT
index because the behavior of each PAT index is clearly defined in Bspec.
Having the abstracted i915_cache_level sitting in between would only cause
more ambiguity. PAT is expected to work much like MOCS already works today,
and by design userspace is expected to select the index that exactly
matches the desired behavior described in the hardware specification.

For these reasons this patch replaces i915_cache_level with PAT index. Also
note, the cache_level is not completely removed yet, because the KMD still
has the need of creating buffer objects with simple cache settings such as
cached, uncached, or writethrough. For kernel objects, cache_level is used
for simplicity and backward compatibility. For Pre-gen12 platforms PAT can
have 1:1 mapping to i915_cache_level, so these two are interchangeable. see
the use of LEGACY_CACHELEVEL.

One consequence of this change is that gen8_pte_encode is no longer working
for gen12 platforms due to the fact that gen12 platforms has different PAT
definitions. In the meantime the mtl_pte_encode introduced specfically for
MTL becomes generic for all gen12 platforms. This patch renames the MTL
PTE encode function into gen12_pte_encode and apply it to all gen12. Even
though this change looks unrelated, but separating them would temporarily
break gen12 PTE encoding, thus squash them in one patch.

Special note: this patch changes the way caching behavior is controlled in
the sense that some objects are left to be managed by userspace. For such
objects we need to be careful not to change the userspace settings.There
are kerneldoc and comments added around obj->cache_coherent, cache_dirty,
and how to bypass the checkings by i915_gem_object_has_cache_level. For
full understanding, these changes need to be looked at together with the
two follow-up patches, one disables the {set|get}_caching ioctl's and the
other adds set_pat extension to the GEM_CREATE uAPI.

Bspec: 63019

Cc: Chris Wilson <chris.p.wilson@linux.intel.com>
Signed-off-by: Fei Yang <fei.yang@intel.com>
Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com>
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Signed-off-by: Andi Shyti <andi.shyti@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230509165200.1740-3-fei.yang@intel.com

drm/i915/ttm: Add I915_BO_PREALLOC

Add a mechanism to preserve existing data when creating
a TTM object with the I915_BO_ALLOC_USER flag. This will
be used in the subsequent patch where the I915_BO_ALLOC_USER
flag will be applied to the framebuffer object. For a pre-allocated
framebuffer without the I915_BO_PREALLOC flag.

TTM would clear the content, which is not desirable.
Cc: Matthew Auld <matthew.auld@intel.com>
Cc: Andi Shyti <andi.shyti@linux.intel.com>
Cc: Andrzej Hajda <andrzej.hajda@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Signed-off-by: Nirmoy Das <nirmoy.das@intel.com>
Reviewed-by: Andrzej Hajda <andrzej.hajda@intel.com>
Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230404143100.10452-1-nirmoy.das@intel.com

drm/i915/gem/i915_gem_ttm_move: Provide a couple of missing descriptions for 'num_pages' and 'ctx'

Fixes the following W=1 kernel build warning(s):

drivers/gpu/drm/i915/gem/i915_gem_ttm_move.c:272: warning: Function parameter or member 'num_pages' not described in 'i915_ttm_memcpy_arg'
drivers/gpu/drm/i915/gem/i915_gem_ttm_move.c:569: warning: Function parameter or member 'ctx' not described in 'i915_ttm_move'

Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Cc: David Airlie <airlied@gmail.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: "Christian König" <christian.koenig@amd.com>
Cc: intel-gfx@lists.freedesktop.org
Cc: dri-devel@lists.freedesktop.org
Cc: linux-media@vger.kernel.org
Cc: linaro-mm-sig@lists.linaro.org
Signed-off-by: Lee Jones <lee@kernel.org>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230331092607.700644-12-lee@kernel.org

drm/i915/ttm: audit remaining bo->resource

In the near future TTM will have NULL bo->resource when the object is
initially created, plus after calling into pipeline-gutting. Try to
handle the remaining cases. In practice NULL bo->resource should be
taken to mean swapped-out or purged object.

v2 (Andrzej):
- Rather make i915_ttm_cpu_maps_iomem() return false with NULL
resource.

References: 516198d317d8 ("drm/i915: audit bo->resource usage v3")
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Nirmoy Das <nirmoy.das@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230130101230.25347-2-matthew.auld@intel.com
Reviewed-by: Nirmoy Das <nirmoy.das@intel.com>
Reviewed-by: Andrzej Hajda <andrzej.hajda@intel.com>
Acked-by: Christian König <ckoenig.leichtzumerken@gmail.com>
Signed-off-by: Christian König <christian.koenig@amd.com>

drm/i915: audit bo->resource usage v3

Make sure we can at least move and alloc TT objects without backing store.

v2: clear the tt object even when no resource is allocated.
v3: add Matthews changes for i915 as well.

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230124125726.13323-1-christian.koenig@amd.com

drm/ttm: merge ttm_bo_api.h and ttm_bo_driver.h v2

Merge and cleanup the two headers into a single description of the
object API. Also move all the documentation to the implementation and
drop unnecessary includes from the header.

No functional change.

v2: minimal checkpatch.pl cleanup

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Arunpravin Paneer Selvam <Arunpravin.PaneerSelvam@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221125102137.1801-4-christian.koenig@amd.com

drm/i915: Refactor ttm ghost obj detection

Currently i915_ttm_to_gem() returns NULL for ttm ghost
object which makes it unclear when we should add a NULL
check for a caller of i915_ttm_to_gem() as ttm ghost
objects are expected behaviour for certain cases.

Create a separate function to detect ttm ghost object and
use that in places where we expect a ghost obj from ttm.

Signed-off-by: Nirmoy Das <nirmoy.das@intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221014131427.21102-1-nirmoy.das@intel.com

drm/i915/ttm: disallow CPU fallback mode for ccs pages

Falling back to memcpy/memset shouldn't be allowed if we know we have
CCS state to manage using the blitter. Otherwise we are potentially
leaving the aux CCS state in an unknown state, which smells like an info
leak.

Fixes: 48760ffe923a ("drm/i915/gt: Clear compress metadata for Flat-ccs objects")
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Cc: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Cc: Jon Bloomfield <jon.bloomfield@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Kenneth Graunke <kenneth@whitecape.org>
Cc: Akeem G Abodunrin <akeem.g.abodunrin@intel.com>
Cc: Ramalingam C <ramalingam.c@intel.com>
Reviewed-by: Ramalingam C <ramalingam.c@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220629174350.384910-12-matthew.auld@intel.com

drm/i915/ttm: handle blitter failure on DG2

If the move or clear operation somehow fails, and the memory underneath
is not cleared, like when moving to lmem, then we currently fallback to
memcpy or memset. However with small-BAR systems this fallback might no
longer be possible. For now we use the set_wedged sledgehammer if we
ever encounter such a scenario, and mark the object as borked to plug
any holes where access to the memory underneath can happen. Add some
basic selftests to exercise this.

v2:
- In the selftests make sure we grab the runtime pm around the reset.
Also make sure we grab the reset lock before checking if the device
is wedged, since the wedge might still be in-progress and hence the
bit might not be set yet.
- Don't wedge or put the object into an unknown state, if the request
construction fails (or similar). Just returning an error and
skipping the fallback should be safe here.
- Make sure we wedge each gt. (Thomas)
- Peek at the unknown_state in io_reserve, that way we don't have to
export or hand roll the fault_wait_for_idle. (Thomas)
- Add the missing read-side barriers for the unknown_state. (Thomas)
- Some kernel-doc fixes. (Thomas)
v3:
- Tweak the ordering of the set_wedged, also add FIXME.

Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Cc: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Cc: Jon Bloomfield <jon.bloomfield@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Kenneth Graunke <kenneth@whitecape.org>
Cc: Akeem G Abodunrin <akeem.g.abodunrin@intel.com>
Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220629174350.384910-11-matthew.auld@intel.com

drm/i915: drop bo->moving dependency

That should now be handled by the common dma_resv framework.

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: intel-gfx@lists.freedesktop.org
Link: https://patchwork.freedesktop.org/patch/msgid/20220407085946.744568-13-christian.koenig@amd.com

dma-buf: specify usage while adding fences to dma_resv obj v7

Instead of distingting between shared and exclusive fences specify
the fence usage while adding fences.

Rework all drivers to use this interface instead and deprecate the old one.

v2: some kerneldoc comments suggested by Daniel
v3: fix a missing case in radeon
v4: rebase on nouveau changes, fix lockdep and temporary disable warning
v5: more documentation updates
v6: separate internal dma_resv changes from this patch, avoids to
disable warning temporary, rebase on upstream changes
v7: fix missed case in lima driver, minimize changes to i915_gem_busy_ioctl

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20220407085946.744568-3-christian.koenig@amd.com

dma-buf/drivers: make reserving a shared slot mandatory v4

Audit all the users of dma_resv_add_excl_fence() and make sure they
reserve a shared slot also when only trying to add an exclusive fence.

This is the next step towards handling the exclusive fence like a
shared one.

v2: fix missed case in amdgpu
v3: and two more radeon, rename function
v4: add one more case to TTM, fix i915 after rebase

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20220406075132.3263-2-christian.koenig@amd.com

drm/i915/ttm: Return some errors instead of trying memcpy move

The i915_ttm_accel_move() function may return error codes that should
be propagated further up the stack rather than consumed assuming that
the accel move failed and could be replaced with a memcpy move.

For -EINTR, -ERESTARTSYS and -EAGAIN, just propagate those codes, rather
than retrying with a memcpy move.

Fixes: 2b0a750caf33 ("drm/i915/ttm: Failsafe migration blits")
Cc: Matthew Auld <matthew.auld@intel.com>
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220201070340.16457-1-thomas.hellstrom@linux.intel.com

drm/i915: Use vma resources for async unbinding

Implement async (non-blocking) unbinding by not syncing the vma before
calling unbind on the vma_resource.
Add the resulting unbind fence to the object's dma_resv from where it is
picked up by the ttm migration code.
Ideally these unbind fences should be coalesced with the migration blit
fence to avoid stalling the migration blit waiting for unbind, as they
can certainly go on in parallel, but since we don't yet have a
reasonable data structure to use to coalesce fences and attach the
resulting fence to a timeline, we defer that for now.

Note that with async unbinding, even while the unbind waits for the
preceding bind to complete before unbinding, the vma itself might have been
destroyed in the process, clearing the vma pages. Therefore we can
only allow async unbinding if we have a refcounted sg-list and keep a
refcount on that for the vma resource pages to stay intact until
binding occurs. If this condition is not met, a request for an async
unbind is diverted to a sync unbind.

v2:
- Use a separate kmem_cache for vma resources for now to isolate their
memory allocation and aid debugging.
- Move the check for vm closed to the actual unbinding thread. Regardless
of whether the vm is closed, we need the unbind fence to properly wait
for capture.
- Clear vma_res::vm on unbind and update its documentation.
v4:
- Take cache coloring into account when searching for vma resources
pending unbind. (Matthew Auld)
v5:
- Fix timeout and error check in i915_vma_resource_bind_dep_await().
- Avoid taking a reference on the object for async binding if
async unbind capable.
- Fix braces around a single-line if statement.
v6:
- Fix up the cache coloring adjustment. (Kernel test robot <lkp@intel.com>)
- Don't allow async unbinding if the vma_res pages are not the same as
the object pages. (Matthew Auld)
v7:
- s/unsigned long/u64/ in a number of places (Matthew Auld)

Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220110172219.107131-5-thomas.hellstrom@linux.intel.com

drm/i915/gem: Use local pointer ttm for __i915_ttm_move

Using local pointer ttm as argument in __i915_ttm_move instead of bo->ttm,
as local pointer was previously assigned to bo->ttm in function.
This will make code a bit more readable.

Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Signed-off-by: Jasmine Newsome <jasmine.newsome@intel.com>
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220104203642.231878-1-jasmine.newsome@intel.com

drm/i915/ttm: Return some errors instead of trying memcpy move

The i915_ttm_accel_move() function may return error codes that should
be propagated further up the stack rather than consumed assuming that
the accel move failed and could be replaced with a memcpy move.

For -EINTR, -ERESTARTSYS and -EAGAIN, just propagate those codes, rather
than retrying with a memcpy move.

Fixes: 2b0a750caf33 ("drm/i915/ttm: Failsafe migration blits")
Cc: Matthew Auld <matthew.auld@intel.com>
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220201070340.16457-1-thomas.hellstrom@linux.intel.com
(cherry picked from commit 29b9702ffe70d83b9970abbccaeb287dfda4409f)
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>

drm/i915: Break out the i915_deps utility

Since it's starting to be used outside the i915 TTM move code, move it
to a separate set of files.

v2:
- Update the documentation.
v4:
- Rebase.

Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211221200050.436316-4-thomas.hellstrom@linux.intel.com

drm/i915: remove questionable fence optimization during copy

First of all as discussed multiple times now kernel copies *must* always
wait for all fences in a BO before actually doing the copy. This is
mandatory.

Additional to that drop the handling when there can't be a shared slot
allocated on the source BO and just properly return an error code.
Otherwise this code path would only be tested under out of memory
conditions.

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211221200050.436316-3-thomas.hellstrom@linux.intel.com
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>

drm/i915: Avoid using the i915_fence_array when collecting dependencies

Since the gt migration code was using only a single fence for
dependencies, these were collected in a dma_fence_array. However, it
turns out that it's illegal to use some dma_fences in a dma_fence_array,
in particular other dma_fence_arrays and dma_fence_chains, and this
causes trouble for us moving forward.

Have the gt migration code instead take a const struct i915_deps for
dependencies. This means we can skip the dma_fence_array creation
and instead pass the struct i915_deps instead to circumvent the
problem.

v2:
- Make the prev_deps() function static. (kernel test robot <lkp@intel.com>)
- Update the struct i915_deps kerneldoc.
v4:
- Rebase.

Fixes: 5652df829b3c ("drm/i915/ttm: Update i915_gem_obj_copy_ttm() to be asynchronous")
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211221200050.436316-2-thomas.hellstrom@linux.intel.com

drm/i915/gem: Use to_gt() helper

Use to_gt() helper consistently throughout the codebase.
Pure mechanical s/i915->gt/to_gt(i915). No functional changes.

Signed-off-by: Michał Winiarski <michal.winiarski@intel.com>
Signed-off-by: Andi Shyti <andi.shyti@linux.intel.com>
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211214193346.21231-6-andi.shyti@linux.intel.com

drm/i915/ttm: Update i915_gem_obj_copy_ttm() to be asynchronous

Update the copy function i915_gem_obj_copy_ttm() to be asynchronous for
future users and update the only current user to sync the objects
as needed after this function.

Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211122214554.371864-7-thomas.hellstrom@linux.intel.com

drm/i915/ttm: Implement asynchronous TTM moves

Don't wait sync while migrating, but rather make the GPU blit await the
dependencies and add a moving fence to the object.

This also enables asynchronous VRAM management in that on eviction,
rather than waiting for the moving fence to expire before freeing VRAM,
it is freed immediately and the fence is stored with the VRAM manager and
handed out to newly allocated objects to await before clears and swapins,
or for kernel objects before setting up gpu vmas or mapping.

To collect dependencies before migrating, add a set of utilities that
coalesce these to a single dma_fence.

What is still missing for fully asynchronous operation is asynchronous vma
unbinding, which is still to be implemented.

This commit substantially reduces execution time in the gem_lmem_swapping
test.

v2:
- Make a couple of functions static.
v4:
- Fix some style issues (Matthew Auld)
- Audit and add more checks for ghost objects (Matthew Auld)
- Add more documentation for the i915_deps utility (Mattew Auld)
- Simplify the i915_deps_sync() function
v6:
- Re-check for fence signaled before returning -EBUSY (Matthew Auld)
- Use dma_resv_iter_is_exclusive() (Matthew Auld)
- Await all dma-resv fences before a migration blit (Matthew Auld)

Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211122214554.371864-6-thomas.hellstrom@linux.intel.com

drm/i915/ttm: Move the i915_gem_obj_copy_ttm() function

Move the i915_gem_obj_copy_ttm() function to i915_gem_ttm_move.h.
This will help keep a number of functions static when introducing
async moves.

Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211122214554.371864-3-thomas.hellstrom@linux.intel.com

drm/i915/ttm: Failsafe migration blits

If the initial fill blit or copy blit of an object fails, the old
content of the data might be exposed and read as soon as either CPU- or
GPU PTEs are set up to point at the pages.

Intercept the blit fence with an async callback that checks the
blit fence for errors and if there are errors performs an async cpu blit
instead. If there is a failure to allocate the async dma_fence_work,
allocate it on the stack and sync wait for the blit to complete.

Add selftests that simulate gpu blit failures and failure to allocate
the async dma_fence_work.

A previous version of this pach used dma_fence_work, now that's
opencoded which adds more code but might lower the latency
somewhat in the common non-error case.

v3:
- Style fixes (Matthew Auld)
v4:
- Use "#if IS_ENABLED()" instead of #ifdef (Matthew Auld)
v5:
- Fix an issue where we, if the dependency was already signaled, might
end up waiting for a memcpy fence that would never signal.
v6:
- Add a missing i915_ttm_memcpy_release() (Matthew Auld)

Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211104110718.688420-3-thomas.hellstrom@linux.intel.com

drm/i915/ttm: Reorganize the ttm move code

We are about to introduce failsafe- and asynchronous migration and
ttm moves.
This will add complexity and code to the TTM move code so it makes sense
to split it out to a separate file to make the i915 TTM code easer to
digest.
Split the i915 TTM move code out and since we will have to change the name
of the gpu_binds_iomem() and cpu_maps_iomem() functions anyway,
we alter the name of gpu_binds_iomem() to i915_ttm_gtt_binds_lmem() which
is more reflecting what it is used for.
With this we also add some more documentation. Otherwise there should be
no functional change.

Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211104110718.688420-2-thomas.hellstrom@linux.intel.com