[Intel-gfx] [PATCH 2/2] drm/i915/display: Do not use stolen on MTL

[Nirmoy Das <nirmoy.das@intel.com>]

Use smem on MTL due to a HW bug in MTL that prevents
reading from stolen memory using LMEM BAR.

Cc: Oak Zeng <oak.zeng@intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Andi Shyti <andi.shyti@linux.intel.com>
Cc: Andrzej Hajda <andrzej.hajda@intel.com>
Signed-off-by: Nirmoy Das <nirmoy.das@intel.com>
---
 drivers/gpu/drm/i915/display/intel_fbdev.c   | 2 ++
 drivers/gpu/drm/i915/display/intel_overlay.c | 7 ++++---
 2 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_fbdev.c b/drivers/gpu/drm/i915/display/intel_fbdev.c
index 1cc0ddc6a310..10e38d60f9ef 100644
--- a/drivers/gpu/drm/i915/display/intel_fbdev.c
+++ b/drivers/gpu/drm/i915/display/intel_fbdev.c
@@ -182,6 +182,8 @@ static int intelfb_alloc(struct drm_fb_helper *helper,
 		obj = i915_gem_object_create_lmem(dev_priv, size,
 						  I915_BO_ALLOC_CONTIGUOUS |
 						  I915_BO_ALLOC_USER);
+	} else if (IS_METEORLAKE(dev_priv)) { /* Wa_22018444074 */
+		obj = i915_gem_object_create_shmem(dev_priv, size);
 	} else {
 		/*
 		 * If the FB is too big, just don't use it since fbdev is not very
diff --git a/drivers/gpu/drm/i915/display/intel_overlay.c b/drivers/gpu/drm/i915/display/intel_overlay.c
index d6fe2bbabe55..05ae446c8a56 100644
--- a/drivers/gpu/drm/i915/display/intel_overlay.c
+++ b/drivers/gpu/drm/i915/display/intel_overlay.c
@@ -1348,12 +1348,13 @@ int intel_overlay_attrs_ioctl(struct drm_device *dev, void *data,
 static int get_registers(struct intel_overlay *overlay, bool use_phys)
 {
 	struct drm_i915_private *i915 = overlay->i915;
-	struct drm_i915_gem_object *obj;
+	struct drm_i915_gem_object *obj = NULL;
 	struct i915_vma *vma;
 	int err;
 
-	obj = i915_gem_object_create_stolen(i915, PAGE_SIZE);
-	if (IS_ERR(obj))
+	if (!IS_METEORLAKE(i915)) /* Wa_22018444074 */
+		obj = i915_gem_object_create_stolen(i915, PAGE_SIZE);
+	if (IS_ERR_OR_NULL(obj))
 		obj = i915_gem_object_create_internal(i915, PAGE_SIZE);
 	if (IS_ERR(obj))
 		return PTR_ERR(obj);
-- 
2.39.0