drm/i915: Compare GGTT view structs instead of types

To allow for views where the view type is not defined by the view type only,
like it is in stereo or rotated 90 degree view, change the semantic to require
the whole view structure for comparison when we match a GGTT view.

This allows including parameters like offset to be included in the view which
is useful for eg. partial views.

v3:
- Rely on ggtt_view type being 0 for non-GGTT vma's, which equals to
  I915_GGTT_VIEW_NORMAL. (Daniel Vetter)
- Do not use potentially slower comparison when we only want to know if
  something is or is not a normal view.
- Rebase on top of rotated view patches. Add rotated view singleton.
- If one view is missing in comparison they're equal only if both are missing.

v4:
- Use comparison helper in obj_to_ggtt_view too. (Tvrtko Ursulin)
- Do WARN_ON if one view is NULL. (Tvrtko Ursulin)

Cc: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

1 files changed, 11 insertions, 0 deletions

diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.h b/drivers/gpu/drm/i915/i915_gem_gtt.h
index 3f0ad9f25441..fc03c99317c9 100644
--- a/drivers/gpu/drm/i915/i915_gem_gtt.h
+++ b/drivers/gpu/drm/i915/i915_gem_gtt.h
@@ -138,6 +138,7 @@ struct i915_ggtt_view {
 };
 
 extern const struct i915_ggtt_view i915_ggtt_view_normal;
+extern const struct i915_ggtt_view i915_ggtt_view_rotated;
 
 enum i915_cache_level;
 
@@ -424,4 +425,14 @@ void i915_gem_restore_gtt_mappings(struct drm_device *dev);
 int __must_check i915_gem_gtt_prepare_object(struct drm_i915_gem_object *obj);
 void i915_gem_gtt_finish_object(struct drm_i915_gem_object *obj);
 
+static inline bool
+i915_ggtt_view_equal(const struct i915_ggtt_view *a,
+                     const struct i915_ggtt_view *b)
+{
+	if (WARN_ON(!a || !b))
+		return false;
+
+	return a->type == b->type;
+}
+
 #endif