4 files changed, 31 insertions, 3 deletions

diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c
index 0cd71dac394e..eb380ee2dc58 100644
--- a/drivers/gpu/drm/drm_atomic_helper.c
+++ b/drivers/gpu/drm/drm_atomic_helper.c
@@ -508,6 +508,12 @@ EXPORT_SYMBOL(drm_atomic_helper_check_planes);
  * Drivers without such needs can directly use this as their ->atomic_check()
  * callback.
  *
+ * This just wraps the two parts of the state checking for planes and modeset
+ * state in the default order: First it calls drm_atomic_helper_check_modeset()
+ * and then drm_atomic_helper_check_planes(). The assumption is that the
+ * ->atomic_check functions depend upon an updated adjusted_mode.clock to
+ * e.g. properly compute watermarks.
+ *
  * RETURNS
  * Zero for success or -errno
  */
@@ -516,11 +522,11 @@ int drm_atomic_helper_check(struct drm_device *dev,
 {
 	int ret;
 
-	ret = drm_atomic_helper_check_planes(dev, state);
+	ret = drm_atomic_helper_check_modeset(dev, state);
 	if (ret)
 		return ret;
 
-	ret = drm_atomic_helper_check_modeset(dev, state);
+	ret = drm_atomic_helper_check_planes(dev, state);
 	if (ret)
 		return ret;
 
diff --git a/drivers/gpu/drm/msm/msm_atomic.c b/drivers/gpu/drm/msm/msm_atomic.c
index f0de412e13dc..f8f18e882f97 100644
--- a/drivers/gpu/drm/msm/msm_atomic.c
+++ b/drivers/gpu/drm/msm/msm_atomic.c
@@ -81,6 +81,26 @@ static void add_fb(struct msm_commit *c, struct drm_framebuffer *fb)
 }
 
 
+int msm_atomic_check(struct drm_device *dev,
+		     struct drm_atomic_state *state)
+{
+	int ret;
+
+	/*
+	 * msm ->atomic_check can update ->mode_changed for pixel format
+	 * changes, hence must be run before we check the modeset changes.
+	 */
+	ret = drm_atomic_helper_check_planes(dev, state);
+	if (ret)
+		return ret;
+
+	ret = drm_atomic_helper_check_modeset(dev, state);
+	if (ret)
+		return ret;
+
+	return ret;
+}
+
 /**
  * drm_atomic_helper_commit - commit validated state object
  * @dev: DRM device
diff --git a/drivers/gpu/drm/msm/msm_drv.c b/drivers/gpu/drm/msm/msm_drv.c
index d3b791b7ddef..473e4d6051e9 100644
--- a/drivers/gpu/drm/msm/msm_drv.c
+++ b/drivers/gpu/drm/msm/msm_drv.c
@@ -29,7 +29,7 @@ static void msm_fb_output_poll_changed(struct drm_device *dev)
 static const struct drm_mode_config_funcs mode_config_funcs = {
 	.fb_create = msm_framebuffer_create,
 	.output_poll_changed = msm_fb_output_poll_changed,
-	.atomic_check = drm_atomic_helper_check,
+	.atomic_check = msm_atomic_check,
 	.atomic_commit = msm_atomic_commit,
 };
 
diff --git a/drivers/gpu/drm/msm/msm_drv.h b/drivers/gpu/drm/msm/msm_drv.h
index 136303818436..d408e02e4ee5 100644
--- a/drivers/gpu/drm/msm/msm_drv.h
+++ b/drivers/gpu/drm/msm/msm_drv.h
@@ -144,6 +144,8 @@ void __msm_fence_worker(struct work_struct *work);
 		(_cb)->func = _func;                         \
 	} while (0)
 
+int msm_atomic_check(struct drm_device *dev,
+		     struct drm_atomic_state *state);
 int msm_atomic_commit(struct drm_device *dev,
 		struct drm_atomic_state *state, bool async);