From: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>
With Xorg+modesetting on skl+ we see the following behaviour:
1. root pixmap is X-tiled
2. client submitted buffers can be Y-tiled (w/ 'Option "dmabuf_capable"')
3. we try to switch from the X-tiled buffer to the Y-tiled buffer
using an async flip (when vsync is disabled).
4. the async flip will be rejected by i915 due to the modifier change
Relax the rules a bit by turning the first async flip into a sync
flip so that we can change the modifier if necessary. Note that
we already convert the first async flip into a sync flip on adl+
in order to reprogram the watermarks.
Signed-off-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>
---
.../gpu/drm/i915/display/intel_atomic_plane.c | 16 +++++++++++++---
drivers/gpu/drm/i915/display/intel_display.c | 7 +++++++
2 files changed, 20 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/drm/i915/display/intel_atomic_plane.c b/drivers/gpu/drm/i915/display/intel_atomic_plane.c
index 06c2455bdd78..605f3b7ef4e0 100644
--- a/drivers/gpu/drm/i915/display/intel_atomic_plane.c
+++ b/drivers/gpu/drm/i915/display/intel_atomic_plane.c
@@ -429,10 +429,20 @@ static bool intel_plane_do_async_flip(struct intel_plane *plane,
* In platforms after DISPLAY13, we might need to override
* first async flip in order to change watermark levels
* as part of optimization.
- * So for those, we are checking if this is a first async flip.
- * For platforms earlier than DISPLAY13 we always do async flip.
+ *
+ * And let's do this for all skl+ so that we can eg. change the
+ * modifier as well.
+ *
+ * TODO: For older platforms there is less reason to do this as
+ * only X-tile is supported with async flips, though we could
+ * extend this so other scanout parameters (stride/etc) could
+ * be changed as well...
+ *
+ * FIXME: Platforms with need_async_flip_disable_wa==true will
+ * now end up doing two sync flips initially. Would be nice to
+ * combine those into just the one sync flip...
*/
- return DISPLAY_VER(i915) < 13 || old_crtc_state->uapi.async_flip;
+ return DISPLAY_VER(i915) < 9 || old_crtc_state->uapi.async_flip;
}
static bool i9xx_must_disable_cxsr(const struct intel_crtc_state *new_crtc_state,
diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
index ccf88c907db2..926e21d9132f 100644
--- a/drivers/gpu/drm/i915/display/intel_display.c
+++ b/drivers/gpu/drm/i915/display/intel_display.c
@@ -6058,6 +6058,13 @@ static int intel_async_flip_check_hw(struct intel_atomic_state *state, struct in
return -EINVAL;
}
+ /*
+ * We turn the first async flip request into a sync flip
+ * so that we can reconfigure the plane (eg. change modifier).
+ */
+ if (!new_crtc_state->do_async_flip)
+ continue;
+
if (old_plane_state->view.color_plane[0].mapping_stride !=
new_plane_state->view.color_plane[0].mapping_stride) {
drm_dbg_kms(&i915->drm,
--
2.41.0
