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path: root/drivers/gpu/drm/i915/i915_vma_types.h
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2023-05-11drm/i915: use pat_index instead of cache_levelFei Yang1-2/+0
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
2022-12-06drm/i915: Introduce guard pages to i915_vmaChris Wilson1-0/+1
Introduce the concept of padding the i915_vma with guard pages before and after. The major consequence is that all ordinary uses of i915_vma must use i915_vma_offset/i915_vma_size and not i915_vma.node.start/size directly, as the drm_mm_node will include the guard pages that surround our object. The biggest connundrum is how exactly to mix requesting a fixed address with guard pages, particularly through the existing uABI. The user does not know about guard pages, so such must be transparent to the user, and so the execobj.offset must be that of the object itself excluding the guard. So a PIN_OFFSET_FIXED must then be exclusive of the guard pages. The caveat is that some placements will be impossible with guard pages, as wrap arounds need to be avoided, and the vma itself will require a larger node. We must not report EINVAL but ENOSPC as these are unavailable locations within the GTT rather than conflicting user requirements. In the next patch, we start using guard pages for scanout objects. While these are limited to GGTT vma, on a few platforms these vma (or at least an alias of the vma) is shared with userspace, so we may leak the existence of such guards if we are not careful to ensure that the execobj.offset is transparent and excludes the guards. (On such platforms like ivb, without full-ppgtt, userspace has to use relocations so the presence of more untouchable regions within its GTT such be of no further issue.) Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Tejas Upadhyay <tejaskumarx.surendrakumar.upadhyay@intel.com> Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Signed-off-by: Andi Shyti <andi.shyti@linux.intel.com> Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20221201203912.346110-1-andi.shyti@linux.intel.com
2022-12-06drm/i915: Limit the display memory alignment to 32 bit instead of 64Andi Shyti1-1/+1
The coming commit "drm/i915: Introduce guard pages to i915_vma" from Chris, was originally changing display_alignment to u32 from u64. The reason is that the display GGTT is and will be limited o 4GB. Put it in a separate patch and use "max(...)" instead of "max_t(64, ...)" when asigning the value. We can safely use max as we know beforehand that the comparison is between two u32 variables. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Andi Shyti <andi.shyti@linux.intel.com> Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20221130235805.221010-2-andi.shyti@linux.intel.com
2022-09-08drm/i915: Rename ggtt_view as gtt_viewNiranjana Vishwanathapura1-21/+21
So far, different views (normal, partial, rotated and remapped) into the same object are only supported for GGTT mappings. But with the upcoming VM_BIND feature, PPGTT will also use the partial view mapping. Hence rename ggtt_view to more generic gtt_view. Signed-off-by: Niranjana Vishwanathapura <niranjana.vishwanathapura@intel.com> Acked-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20220901183854.3446-1-niranjana.vishwanathapura@intel.com
2022-03-07drm/i915: Remove the vma refcountThomas Hellström1-1/+0
Now that i915_vma_parked() is taking the object lock on vma destruction, and the only user of the vma refcount, i915_gem_object_unbind() also takes the object lock, remove the vma refcount. v3: Documentation update. Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com> Reviewed-by: Niranjana Vishwanathapura <niranjana.vishwanathapura@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20220304082641.308069-3-thomas.hellstrom@linux.intel.com
2022-03-07drm/i915: Remove the vm open countThomas Hellström1-0/+7
vms are not getting properly closed. Rather than fixing that, Remove the vm open count and instead rely on the vm refcount. The vm open count existed solely to break the strong references the vmas had on the vms. Now instead make those references weak and ensure vmas are destroyed when the vm is destroyed. Unfortunately if the vm destructor and the object destructor both wants to destroy a vma, that may lead to a race in that the vm destructor just unbinds the vma and leaves the actual vma destruction to the object destructor. However in order for the object destructor to ensure the vma is unbound it needs to grab the vm mutex. In order to keep the vm mutex alive until the object destructor is done with it, somewhat hackishly grab a vm_resv refcount that is released late in the vma destruction process, when the vm mutex is no longer needed. v2: Address review-comments from Niranjana - Clarify that the struct i915_address_space::skip_pte_rewrite is a hack and should ideally be replaced in an upcoming patch. - Remove an unneeded continue in clear_vm_list and update comment. v3: - Documentation update - Commit message formatting Co-developed-by: Niranjana Vishwanathapura <niranjana.vishwanathapura@intel.com> Signed-off-by: Niranjana Vishwanathapura <niranjana.vishwanathapura@intel.com> Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com> Reviewed-by: Niranjana Vishwanathapura <niranjana.vishwanathapura@intel.com> Reviewed-by: Matthew Auld <matthew.auld@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20220304082641.308069-2-thomas.hellstrom@linux.intel.com
2022-01-18Merge drm/drm-next into drm-intel-gt-nextTvrtko Ursulin1-5/+14
Maarten needs backmerge to account for header file renames/changes which landed via drm-intel-next and are interfering with his pinning work. Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
2022-01-11drm/i915: Use the vma resource as argument for gtt binding / unbindingThomas Hellström1-8/+6
When introducing asynchronous unbinding, the vma itself may no longer be alive when the actual binding or unbinding takes place. Update the gtt i915_vma_ops accordingly to take a struct i915_vma_resource instead of a struct i915_vma for the bind_vma() and unbind_vma() ops. Similarly change the insert_entries() op for struct i915_address_space. Replace a couple of i915_vma_snapshot members with their newly introduced i915_vma_resource counterparts, since they have the same lifetime. Also make sure to avoid changing the struct i915_vma_flags (in particular the bind flags) async. That should now only be done sync under the vm mutex. v2: - Update the vma_res::bound_flags when binding to the aliased ggtt v6: - Remove I915_VMA_ALLOC_BIT (Matthew Auld) - Change some members of struct i915_vma_resource from unsigned long to u64 (Matthew Auld) v7: - Fix vma resource size parameters to be u64 rather than unsigned long (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/20220110172219.107131-3-thomas.hellstrom@linux.intel.com
2022-01-11drm/i915: Initial introduction of vma resourcesThomas Hellström1-0/+5
Introduce vma resources, sort of similar to TTM resources, needed for asynchronous bind management. Initially we will use them to hold completion of unbinding when we capture data from a vma, but they will be used extensively in upcoming patches for asynchronous vma unbinding. v6: - Some documentation updates 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/20220110172219.107131-2-thomas.hellstrom@linux.intel.com
2021-12-23Merge tag 'drm-intel-gt-next-2021-12-23' of ↵Dave Airlie1-1/+0
git://anongit.freedesktop.org/drm/drm-intel into drm-next Driver Changes: - Added bits of DG2 support around page table handling (Stuart Summers, Matthew Auld) - Fixed wakeref leak in PMU busyness during reset in GuC mode (Umesh Nerlige Ramappa) - Fixed debugfs access crash if GuC failed to load (John Harrison) - Bring back GuC error log to error capture, undoing accidental earlier breakage (Thomas Hellström) - Fixed memory leak in error capture caused by earlier refactoring (Thomas Hellström) - Exclude reserved stolen from driver use (Chris Wilson) - Add memory region sanity checking and optional full test (Chris Wilson) - Fixed buffer size truncation in TTM shmemfs backend (Robert Beckett) - Use correct lock and don't overwrite internal data structures when stealing GuC context ids (Matthew Brost) - Don't hog IRQs when destroying GuC contexts (John Harrison) - Make GuC to Host communication more robust (Matthew Brost) - Continuation of locking refactoring around VMA and backing store handling (Maarten Lankhorst) - Improve performance of reading GuC log from debugfs (John Harrison) - Log when GuC fails to reset an engine (John Harrison) - Speed up GuC/HuC firmware loading by requesting RP0 (Vinay Belgaumkar) - Further work on asynchronous VMA unbinding (Thomas Hellström, Christian König) - Refactor GuC/HuC firmware handling to prepare for future platforms (John Harrison) - Prepare for future different GuC/HuC firmware signing key sizes (Daniele Ceraolo Spurio, Michal Wajdeczko) - Add noreclaim annotations (Matthew Auld) - Remove racey GEM_BUG_ON between GPU reset and GuC communication handling (Matthew Brost) - Refactor i915->gt with to_gt(i915) to prepare for future platforms (Michał Winiarski, Andi Shyti) - Increase GuC log size for CONFIG_DEBUG_GEM (John Harrison) - Fixed engine busyness in selftests when in GuC mode (Umesh Nerlige Ramappa) - Make engine parking work with PREEMPT_RT (Sebastian Andrzej Siewior) - Replace X86_FEATURE_PAT with pat_enabled() (Lucas De Marchi) - Selftest for stealing of guc ids (Matthew Brost) Signed-off-by: Dave Airlie <airlied@redhat.com> From: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/YcRvKO5cyPvIxVCi@tursulin-mobl2
2021-12-20drm/i915: Remove pages_mutex and intel_gtt->vma_ops.set/clear_pages members, v3.Maarten Lankhorst1-1/+0
Big delta, but boils down to moving set_pages to i915_vma.c, and removing the special handling, all callers use the defaults anyway. We only remap in ggtt, so default case will fall through. Because we still don't require locking in i915_vma_unpin(), handle this by using xchg in get_pages(), as it's locked with obj->mutex, and cmpxchg in unpin, which only fails if we race a against a new pin. Changes since v1: - aliasing gtt sets ZERO_SIZE_PTR, not -ENODEV, remove special case from __i915_vma_get_pages(). (Matt) Changes since v2: - Free correct old pages in __i915_vma_get_pages(). (Matt) Remove race of clearing vma->pages accidentally from put, free it but leave it set, as only get has the lock. Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20211216142749.1966107-4-maarten.lankhorst@linux.intel.com Reviewed-by: Matthew Auld <matthew.auld@intel.com>
2021-12-10Merge tag 'drm-intel-gt-next-2021-12-09' of ↵Dave Airlie1-1/+0
git://anongit.freedesktop.org/drm/drm-intel into drm-next Core Changes: - Fix PENDING_ERROR leak in dma_fence_array_signaled() (Thomas Hellström) Driver Changes: - Fix runtime PM handling during PXP suspend (Tejas Upadhyay) - Improve eviction performance on discrete by implementing async TTM moves (Thomas Hellström, Maarten Lankhorst) - Improve robustness of error capture under memory pressure (Thomas Hellström) - Fix GuC PMU versus GPU reset handling (Umesh Nerlige Ramappa) - Use per device iommu check (Tvrtko Ursulin) - Make error capture work with async migration (Thomas Hellström) - Revert incorrect implementation of Wa_1508744258 causing hangs (José Roberto de Souza) - Disable coarse power gating on some DG2 steppings workaround (Matt Roper) - Add IC cache invalidation workaround on DG2 (Ramalingam C) - Move two Icelake workarounds to the right place (Raviteja Goud Talla) - Fix error pointer dereference in i915_gem_do_execbuffer() (Dan Carpenter) - Fixup a couple of generic and DG2 specific issues in migration code (Matthew Auld) - Fix kernel-doc warnings in i915_drm_object.c (Randy Dunlap) - Drop stealing of bits from i915_sw_fence function pointer (Matthew Brost) - Introduce new macros for i915 PTE (Michael Cheng) - Prep work for engine reset by reset domain lookup (Tejas Upadhyay) - Fixup drm-intel-gt-next build failure (Matthew Auld) - Fix live_engine_busy_stats selftests in GuC mode (Umesh Nerlige Ramappa) - Remove dma_resv_prune (Maarten Lankhorst) - Preserve huge pages enablement after driver reload (Matthew Auld) - Fix a NULL pointer dereference in igt_request_rewind() (selftests) (Zhou Qingyang) - Add workaround numbers to GEN7_COMMON_SLICE_CHICKEN1 whitelisting (José Roberto de Souza) - Increase timeouts in i915_gem_contexts selftests to handle GuC being slower (Bruce Chang) Signed-off-by: Dave Airlie <airlied@redhat.com> # Conflicts: # drivers/gpu/drm/i915/display/intel_fbc.c From: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/YbIBOeqhn+nPzaYD@tursulin-mobl2
2021-11-19drm/i915: Remove resv from i915_vmaMaarten Lankhorst1-1/+0
It's just an alias to vma->obj->base.resv, no need to duplicate it. Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Reviewed-by: Niranjana Vishwanathapura <niranjana.vishwanathapura@intel.com> Signed-off-by: Matthew Auld <matthew.auld@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20211117142024.1043017-5-matthew.auld@intel.com
2021-11-02drm/i915/adlp/fb: Fix remapping of linear CCS AUX surfacesImre Deak1-5/+14
During remapping CCS FBs the CCS AUX surface mapped size and offset->x,y coordinate calculations assumed a tiled layout. This works as long as the CCS surface height is aligned to 64 lines (ensuring a 4k bytes CCS surface tile layout). However this alignment is not required by the HW (and the driver doesn't enforces it either). Add the remapping logic required to remap the pages of CCS surfaces without the above alignment, assuming the natural linear layout of the CCS surface (vs. tiled main surface layout). Cc: Juha-Pekka Heikkila <juhapekka.heikkila@gmail.com> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> Fixes: 3d1adc3d64cf ("drm/i915/adlp: Add support for remapping CCS FBs") Signed-off-by: Imre Deak <imre.deak@intel.com> Reviewed-by: Juha-Pekka Heikkila <juhapekka.heikkila@gmail.com> Link: https://patchwork.freedesktop.org/patch/msgid/20211026225105.2783797-5-imre.deak@intel.com
2021-09-23drm/i915/adlp: Add support for remapping CCS FBsImre Deak1-3/+4
Add support for remapping CCS FBs on ADL-P to remove the restriction of the power-of-two sized stride and the 2MB surface offset alignment for these FBs. We can only remap the tiles on the main surface, not the tiles on the CCS surface, so userspace has to generate the CCS surface aligning to the POT size padded main surface stride (by programming the AUX pagetable accordingly). For the required AUX pagetable setup, this requires that either the main surface stride is 8 tiles or that the stride is 16 tiles aligned (= 64 kbytes, the area mapped by one AUX PTE). v2: - Init intel_remapped_info::plane_alignment only for remapped views and do this from intel_fb_view_init(). Cc: Juha-Pekka Heikkila <juhapekka.heikkila@gmail.com> Signed-off-by: Imre Deak <imre.deak@intel.com> Reviewed-by: Juha-Pekka Heikkila <juhapekka.heikkila@gmail.com> Link: https://patchwork.freedesktop.org/patch/msgid/20210906182715.3915100-6-imre.deak@intel.com
2021-04-28drm/i915: Remove stray newlinesVille Syrjälä1-1/+0
A bunch of files have a stray newline at the end. Remove it. Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20210318181039.17260-2-ville.syrjala@linux.intel.com Reviewed-by: Imre Deak <imre.deak@intel.com>
2021-03-29drm/i915: Add support for FBs requiring a POT stride alignmentImre Deak1-1/+1
An upcoming platform has a restriction that the FB stride must be power-of-two aligned. To support framebuffer layouts that are not in this layout add a logic that pads the tile rows to the POT aligned size. The HW won't read the padding PTEs, so these don't have to point to an allocated address, or even have their valid flag set. So use a NULL PTE instead for instance the scratch page, which is simple and keeps the SG table compact. v2: - Simplify plane_view_dst_stride(). (Ville) - Pass pitch_tiles as unsigned int. v3: - Drop unintentional s/plane_state->rotation/plane_config->rotation/ change. Signed-off-by: Imre Deak <imre.deak@intel.com> Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20210325214808.2071517-24-imre.deak@intel.com
2021-03-29drm/i915: s/stride/src_stride/ in the intel_remapped_plane_info structImre Deak1-1/+1
An upcoming patch adds a new dst_stride field to the intel_remapped_plane_info struct, so for clarity rename the current stride field to src_stride. Signed-off-by: Imre Deak <imre.deak@intel.com> Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20210325214808.2071517-23-imre.deak@intel.com
2021-03-29drm/i915: Shrink the size of intel_remapped_plane_info structImre Deak1-4/+8
Save some place in the GTT VMAs by using a u16 instead of unsigned int to store the view dimensions. The maximum FB stride is 256kB which is 4096 tiles in the worst case (yf-tiles), the maximum FB height is 16k pixels, which is 16384 tiles in the worst case (linear 4x1 tiled FB). v2: - Fix worst case tile height formula in commit log. (Ville) - Add an assign_chk_ovf helper to simplify the related assignments. v3: - Enclose params of the assign_chk_ovf macro in parentheses. Signed-off-by: Imre Deak <imre.deak@intel.com> Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20210325214808.2071517-21-imre.deak@intel.com
2021-01-21drm/i915/gem: Protect used framebuffers from casual evictionChris Wilson1-0/+3
In the shrinker, we protect framebuffers from light reclaim as we typically expect framebuffers to be reused in the near future (and with low latency requirements). We can apply the same logic to the GGTT eviction and defer framebuffers to the second pass only used if the caller is desperate enough to wait for space to become available. In most cases, the caller will use a smaller partial vma instead of trying to force the object into the GGTT if doing so will cause other users to be evicted. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Reviewed-by: Matthew Auld <matthew.auld@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20210119214336.1463-5-chris@chris-wilson.co.uk
2020-07-03drm/i915: Export ppgtt_bind_vmaChris Wilson1-1/+0
Reuse the ppgtt_bind_vma() for aliasing_ppgtt_bind_vma() so we can reduce some code near-duplication. The catch is that we need to then pass along the i915_address_space and not rely on vma->vm, as they differ with the aliasing-ppgtt. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Reviewed-by: Andi Shyti <andi.shyti@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20200703102519.26539-1-chris@chris-wilson.co.uk
2020-03-04drm/i915/gem: Extract transient execbuf flags from i915_vmaChris Wilson1-11/+0
For our convenience, and to avoid frequent allocations, we placed some lists we use for execbuf inside the common i915_vma struct. As we look to parallelise execbuf, such fields guarded by the struct_mutex BKL must be pulled under local control. Instead of using the i915_vma as our primary means of tracking the user's list of objects and their virtual mappings, we use a local eb_vma with the same lists as before (just now local not global). This should allow us to only perform the lookup of vma used for execution once during the execbuf ioctl, as currently we need to remove our secrets from inside i915_vma everytime we drop the struct_mutex as another execbuf may use the shared locations. Once potential user visible consequence is that we can remove the requirement that the execobj[] be unique, and only require that they do not conflict (i.e. you cannot softpin the same object into two locations. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20200303204345.1859734-2-chris@chris-wilson.co.uk
2020-01-07drm/i915/gtt: split up i915_gem_gttMatthew Auld1-0/+294
Attempt to split i915_gem_gtt.[ch] into more manageable chunks. Suggested-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Matthew Auld <matthew.auld@intel.com> Cc: Chris Wilson <chris@chris-wilson.co.uk> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Link: https://patchwork.freedesktop.org/patch/msgid/20200107134009.3255354-1-chris@chris-wilson.co.uk