Currently, on a handful of ASICs. We allow the framebuffer for a given
plane to exist in either VRAM or GTT. However, if the plane's new
framebuffer is in a different memory domain than it's previous
framebuffer, flipping between them can cause the screen to flicker. So,
to fix this, don't perform an immediate flip in the aforementioned case.

Cc: sta...@vger.kernel.org
Link: https://gitlab.freedesktop.org/drm/amd/-/issues/2354
Fixes: 81d0bcf99009 ("drm/amdgpu: make display pinning more flexible (v2)")
Signed-off-by: Hamza Mahfooz <hamza.mahf...@amd.com>
---
v2: make a number of clarifications to the commit message and drop
    locking.
---
 .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c    | 16 ++++++++++++++--
 1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c 
b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
index da3045fdcb6d..fd1b323f0e85 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -7897,6 +7897,13 @@ static void amdgpu_dm_commit_cursors(struct 
drm_atomic_state *state)
                        amdgpu_dm_plane_handle_cursor_update(plane, 
old_plane_state);
 }
 
+static inline uint32_t get_mem_type(struct drm_framebuffer *fb)
+{
+       struct amdgpu_bo *abo = gem_to_amdgpu_bo(fb->obj[0]);
+
+       return abo->tbo.resource ? abo->tbo.resource->mem_type : 0;
+}
+
 static void amdgpu_dm_commit_planes(struct drm_atomic_state *state,
                                    struct dc_state *dc_state,
                                    struct drm_device *dev,
@@ -7916,6 +7923,7 @@ static void amdgpu_dm_commit_planes(struct 
drm_atomic_state *state,
                        to_dm_crtc_state(drm_atomic_get_old_crtc_state(state, 
pcrtc));
        int planes_count = 0, vpos, hpos;
        unsigned long flags;
+       uint32_t mem_type;
        u32 target_vblank, last_flip_vblank;
        bool vrr_active = amdgpu_dm_crtc_vrr_active(acrtc_state);
        bool cursor_update = false;
@@ -8035,13 +8043,17 @@ static void amdgpu_dm_commit_planes(struct 
drm_atomic_state *state,
                        }
                }
 
+               mem_type = get_mem_type(old_plane_state->fb);
+
                /*
                 * Only allow immediate flips for fast updates that don't
-                * change FB pitch, DCC state, rotation or mirroing.
+                * change memory domain, FB pitch, DCC state, rotation or
+                * mirroring.
                 */
                bundle->flip_addrs[planes_count].flip_immediate =
                        crtc->state->async_flip &&
-                       acrtc_state->update_type == UPDATE_TYPE_FAST;
+                       acrtc_state->update_type == UPDATE_TYPE_FAST &&
+                       (!mem_type || get_mem_type(fb) == mem_type);
 
                timestamp_ns = ktime_get_ns();
                bundle->flip_addrs[planes_count].flip_timestamp_in_us = 
div_u64(timestamp_ns, 1000);
-- 
2.40.0

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