[Intel-gfx] [PATCH v2] drm/i915/gt: Temporarily force MTL into uncached mode

[Jonathan Cavitt]

FIXME: CAT errors are cropping up on MTL.  This removes them,
but the real root cause must still be diagnosed.

Signed-off-by: Jonathan Cavitt <jonathan.cavitt at intel.com>
---

v2: Apply FIXME to shmem_utils as well.

 drivers/gpu/drm/i915/gt/intel_gt.c     | 6 +++++-
 drivers/gpu/drm/i915/gt/intel_lrc.c    | 5 ++++-
 drivers/gpu/drm/i915/gt/shmem_utils.c  | 8 +++++++-
 drivers/gpu/drm/i915/gt/uc/intel_guc.c | 5 ++++-
 4 files changed, 20 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/i915/gt/intel_gt.c b/drivers/gpu/drm/i915/gt/intel_gt.c
index ed32bf5b15464..b52c8eb0b033f 100644
--- a/drivers/gpu/drm/i915/gt/intel_gt.c
+++ b/drivers/gpu/drm/i915/gt/intel_gt.c
@@ -1026,8 +1026,12 @@ enum i915_map_type intel_gt_coherent_map_type(struct intel_gt *gt,
 	/*
 	 * Wa_22016122933: always return I915_MAP_WC for Media
 	 * version 13.0 when the object is on the Media GT
+	 *
+	 * FIXME: CAT errors are cropping up on MTL.  This removes them,
+	 * but the real root cause must still be diagnosed.
 	 */
-	if (i915_gem_object_is_lmem(obj) || intel_gt_needs_wa_22016122933(gt))
+	if (i915_gem_object_is_lmem(obj) || intel_gt_needs_wa_22016122933(gt) ||
+	    IS_METEORLAKE(gt->i915))
 		return I915_MAP_WC;
 	if (HAS_LLC(gt->i915) || always_coherent)
 		return I915_MAP_WB;
diff --git a/drivers/gpu/drm/i915/gt/intel_lrc.c b/drivers/gpu/drm/i915/gt/intel_lrc.c
index eaf66d9031665..8aaa4df84cb3e 100644
--- a/drivers/gpu/drm/i915/gt/intel_lrc.c
+++ b/drivers/gpu/drm/i915/gt/intel_lrc.c
@@ -1124,8 +1124,11 @@ __lrc_alloc_state(struct intel_context *ce, struct intel_engine_cs *engine)
 		 * Wa_22016122933: For Media version 13.0, all Media GT shared
 		 * memory needs to be mapped as WC on CPU side and UC (PAT
 		 * index 2) on GPU side.
+		 *
+		 * FIXME: CAT errors are cropping up on MTL.  This removes them,
+		 * but the real root cause must still be diagnosed.
 		 */
-		if (intel_gt_needs_wa_22016122933(engine->gt))
+		if (intel_gt_needs_wa_22016122933(engine->gt) || IS_METEORLAKE(engine->i915))
 			i915_gem_object_set_cache_coherency(obj, I915_CACHE_NONE);
 	}
 
diff --git a/drivers/gpu/drm/i915/gt/shmem_utils.c b/drivers/gpu/drm/i915/gt/shmem_utils.c
index bccc3a1200bc6..a026c216fd286 100644
--- a/drivers/gpu/drm/i915/gt/shmem_utils.c
+++ b/drivers/gpu/drm/i915/gt/shmem_utils.c
@@ -43,7 +43,13 @@ struct file *shmem_create_from_object(struct drm_i915_gem_object *obj)
 		return file;
 	}
 
-	map_type = i915_gem_object_is_lmem(obj) ? I915_MAP_WC : I915_MAP_WB;
+	/*
+	 * FIXME: CAT errors are cropping up on MTL.  This removes them,
+	 * but the real root cause must still be diagnosed.
+	 */
+	map_type = i915_gem_object_is_lmem(obj) ||
+		   IS_METEORLAKE(to_i915(obj->base.dev)) ?
+		   I915_MAP_WC : I915_MAP_WB;
 	ptr = i915_gem_object_pin_map_unlocked(obj, map_type);
 	if (IS_ERR(ptr))
 		return ERR_CAST(ptr);
diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc.c b/drivers/gpu/drm/i915/gt/uc/intel_guc.c
index 27df41c53b890..e3a7d61506188 100644
--- a/drivers/gpu/drm/i915/gt/uc/intel_guc.c
+++ b/drivers/gpu/drm/i915/gt/uc/intel_guc.c
@@ -774,8 +774,11 @@ struct i915_vma *intel_guc_allocate_vma(struct intel_guc *guc, u32 size)
 	 * Wa_22016122933: For Media version 13.0, all Media GT shared
 	 * memory needs to be mapped as WC on CPU side and UC (PAT
 	 * index 2) on GPU side.
+	 *
+	 * FIXME: CAT errors are cropping up on MTL.  This removes them,
+	 * but the real root cause must still be diagnosed.
 	 */
-	if (intel_gt_needs_wa_22016122933(gt))
+	if (intel_gt_needs_wa_22016122933(gt) || IS_METEORLAKE(gt->i915))
 		i915_gem_object_set_cache_coherency(obj, I915_CACHE_NONE);
 
 	vma = i915_vma_instance(obj, &gt->ggtt->vm, NULL);
-- 
2.25.1