In case of ICL and older generations disabling plane and/or disabling async update is always performed on vblank, but if async update is enabled PLANE_SURF register is updated asynchronously. Writing 0 to PLANE_SURF when plane is still enabled can cause DMAR/PIPE errors. On the other side PLANE_SURF is used to arm plane registers - we need to write to it to trigger update on VBLANK, writting current value should be safe - the buffer address is valid till vblank. Signed-off-by: Andrzej Hajda <andrzej.hajda@xxxxxxxxx> --- drivers/gpu/drm/i915/display/skl_universal_plane.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/i915/display/skl_universal_plane.c b/drivers/gpu/drm/i915/display/skl_universal_plane.c index bcfde81e4d0866..bc9ed60a2d349e 100644 --- a/drivers/gpu/drm/i915/display/skl_universal_plane.c +++ b/drivers/gpu/drm/i915/display/skl_universal_plane.c @@ -615,11 +615,13 @@ skl_plane_disable_arm(struct intel_plane *plane, struct drm_i915_private *dev_priv = to_i915(plane->base.dev); enum plane_id plane_id = plane->id; enum pipe pipe = plane->pipe; + u32 plane_surf; skl_write_plane_wm(plane, crtc_state); intel_de_write_fw(dev_priv, PLANE_CTL(pipe, plane_id), 0); - intel_de_write_fw(dev_priv, PLANE_SURF(pipe, plane_id), 0); + plane_surf = intel_de_read_fw(dev_priv, PLANE_SURF(pipe, plane_id)); + intel_de_write_fw(dev_priv, PLANE_SURF(pipe, plane_id), plane_surf); } static void @@ -629,6 +631,7 @@ icl_plane_disable_arm(struct intel_plane *plane, struct drm_i915_private *dev_priv = to_i915(plane->base.dev); enum plane_id plane_id = plane->id; enum pipe pipe = plane->pipe; + u32 plane_surf; if (icl_is_hdr_plane(dev_priv, plane_id)) intel_de_write_fw(dev_priv, PLANE_CUS_CTL(pipe, plane_id), 0); @@ -637,7 +640,8 @@ icl_plane_disable_arm(struct intel_plane *plane, intel_psr2_disable_plane_sel_fetch(plane, crtc_state); intel_de_write_fw(dev_priv, PLANE_CTL(pipe, plane_id), 0); - intel_de_write_fw(dev_priv, PLANE_SURF(pipe, plane_id), 0); + plane_surf = intel_de_read_fw(dev_priv, PLANE_SURF(pipe, plane_id)); + intel_de_write_fw(dev_priv, PLANE_SURF(pipe, plane_id), plane_surf); } static bool -- 2.25.1
