drm/i915: Support Async Flip on Linear buffers

Starting from Gen12 Async Flip is supported on linear buffers.
This patch enables support for async on linear buffer.

UseCase: In Hybrid graphics, for hardware unsupported pixel formats it
will be converted to linear memory and then composed.

v2: Added use case
v3: Added FIXME for ICL indicating the restrictions

Signed-off-by: Arun R Murthy <arun.r.murthy@intel.com>
Reviewed-by: Stanislav Lisovskiy <stanislav.lisovskiy@intel.com>
Signed-off-by: Animesh Manna <animesh.manna@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220906041806.4095575-1-arun.r.murthy@intel.com

diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
index 09320e1..0490c64 100644 (file)
--- a/drivers/gpu/drm/i915/display/intel_display.c
+++ b/drivers/gpu/drm/i915/display/intel_display.c
@@ -5995,6 +5995,20 @@ static int intel_async_flip_check_hw(struct intel_atomic_state *state, struct in
                 * this selectively if required.
                 */
                switch (new_plane_state->hw.fb->modifier) {
+               case DRM_FORMAT_MOD_LINEAR:
+                       /*
+                        * FIXME: Async on Linear buffer is supported on ICL as
+                        * but with additional alignment and fbc restrictions
+                        * need to be taken care of. These aren't applicable for
+                        * gen12+.
+                        */
+                       if (DISPLAY_VER(i915) < 12) {
+                               drm_dbg_kms(&i915->drm,
+                                           "[PLANE:%d:%s] Modifier does not support async flips\n",
+                                           plane->base.base.id, plane->base.name);
+                               return -EINVAL;
+                       }
+
                case I915_FORMAT_MOD_X_TILED:
                case I915_FORMAT_MOD_Y_TILED:
                case I915_FORMAT_MOD_Yf_TILED: