drm/amd/display: only accept async flips for fast updates

From Simon Ser
4385420741743247a7bdedb5c0b1eb5efe9a9edd in linux-6.1.y/6.1.42
1ca67aba8d11c2849d395013e1fdce02918d5657 in mainline linux

diff --git a/sys/dev/pci/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/sys/dev/pci/drm/amd/display/amdgpu_dm/amdgpu_dm.c
index 21e07a1..39e027e 100644 (file)
--- a/sys/dev/pci/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/sys/dev/pci/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -7761,7 +7761,15 @@ static void amdgpu_dm_commit_planes(struct drm_atomic_state *state,
                 * Only allow immediate flips for fast updates that don't
                 * change memory domain, FB pitch, DCC state, rotation or
                 * mirroring.
+                *
+                * dm_crtc_helper_atomic_check() only accepts async flips with
+                * fast updates.
                 */
+               if (crtc->state->async_flip &&
+                   acrtc_state->update_type != UPDATE_TYPE_FAST)
+                       drm_warn_once(state->dev,
+                                     "[PLANE:%d:%s] async flip with non-fast update\n",
+                                     plane->base.id, plane->name);
                bundle->flip_addrs[planes_count].flip_immediate =
                        crtc->state->async_flip &&
                        acrtc_state->update_type == UPDATE_TYPE_FAST &&

diff --git a/sys/dev/pci/drm/amd/display/amdgpu_dm/amdgpu_dm_crtc.c b/sys/dev/pci/drm/amd/display/amdgpu_dm/amdgpu_dm_crtc.c
index 1ec643a..b9b70f4 100644 (file)
--- a/sys/dev/pci/drm/amd/display/amdgpu_dm/amdgpu_dm_crtc.c
+++ b/sys/dev/pci/drm/amd/display/amdgpu_dm/amdgpu_dm_crtc.c
@@ -406,6 +406,18 @@ static int dm_crtc_helper_atomic_check(struct drm_crtc *crtc,
                return -EINVAL;
        }
 
+       /*
+        * Only allow async flips for fast updates that don't change the FB
+        * pitch, the DCC state, rotation, etc.
+        */
+       if (crtc_state->async_flip &&
+           dm_crtc_state->update_type != UPDATE_TYPE_FAST) {
+               drm_dbg_atomic(crtc->dev,
+                              "[CRTC:%d:%s] async flips are only supported for fast updates\n",
+                              crtc->base.id, crtc->name);
+               return -EINVAL;
+       }
+
        /* In some use cases, like reset, no stream is attached */
        if (!dm_crtc_state->stream)
                return 0;