[RFC PATCH 32/37] drm: atomic_helper: Reference, not duplicate, modes

[Daniel Stone]

Take a reference to existing modes, rather than duplicating them to
create new ones.

Signed-off-by: Daniel Stone <daniels at collabora.com>
---
 drivers/gpu/drm/drm_atomic_helper.c | 49 ++++++++++++++++++-------------------
 1 file changed, 24 insertions(+), 25 deletions(-)

diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c
index bc7b629..f5ee83c 100644
--- a/drivers/gpu/drm/drm_atomic_helper.c
+++ b/drivers/gpu/drm/drm_atomic_helper.c
@@ -260,7 +260,12 @@ mode_fixup(struct drm_atomic_state *state)
 		if (!crtc_state || !crtc_state->mode_changed)
 			continue;
 
-		drm_mode_copy(&crtc_state->adjusted_mode, crtc_state->mode);
+		if (crtc_state->mode)
+			drm_mode_copy(&crtc_state->adjusted_mode,
+			              crtc_state->mode);
+		else
+			memset(&crtc_state->adjusted_mode, 0,
+			       sizeof(crtc_state->adjusted_mode));
 	}
 
 	for (i = 0; i < state->num_connector; i++) {
@@ -699,14 +704,12 @@ set_routing_links(struct drm_device *dev, struct drm_atomic_state *old_state)
 		if (!crtc)
 			continue;
 
-		if (crtc->state->mode) {
-			if (crtc->mode)
-				drm_mode_destroy(dev, crtc->mode);
-			crtc->mode = drm_mode_duplicate(dev, crtc->state->mode);
-		} else if (crtc->mode) {
+		if (crtc->mode)
 			drm_mode_destroy(dev, crtc->mode);
-			crtc->mode = NULL;
-		}
+		crtc->mode = crtc->state->mode;
+		if (crtc->mode)
+			drm_mode_reference(crtc->mode);
+
 		crtc->enabled = crtc->state->enable;
 		crtc->x = crtc->primary->state->src_x >> 16;
 		crtc->y = crtc->primary->state->src_y >> 16;
@@ -731,8 +734,9 @@ crtc_set_mode(struct drm_device *dev, struct drm_atomic_state *old_state)
 		funcs = crtc->helper_private;
 
 		if (crtc->state->enable && funcs->mode_set_nofb) {
-			DRM_DEBUG_ATOMIC("modeset on [CRTC:%d]\n",
-					 crtc->base.id);
+			DRM_DEBUG_ATOMIC("modeset on [CRTC:%d] [MODE:%d]\n",
+					 crtc->base.id,
+					 crtc->state->mode ? crtc->state->mode->base.id : 0);
 
 			funcs->mode_set_nofb(crtc);
 		}
@@ -1652,7 +1656,9 @@ retry:
 	crtc_state->active = true;
 	if (crtc_state->mode)
 		drm_mode_destroy(crtc->dev, crtc_state->mode);
-	crtc_state->mode = drm_mode_duplicate(crtc->dev, set->mode);
+	crtc_state->mode = set->mode;
+	if (crtc_state->mode)
+		drm_mode_reference(crtc_state->mode);
 
 	ret = drm_atomic_set_crtc_for_plane(primary_state, crtc);
 	if (ret != 0)
@@ -1660,12 +1666,12 @@ retry:
 	drm_atomic_set_fb_for_plane(primary_state, set->fb);
 	primary_state->crtc_x = 0;
 	primary_state->crtc_y = 0;
-	primary_state->crtc_h = set->mode->vdisplay;
-	primary_state->crtc_w = set->mode->hdisplay;
+	primary_state->crtc_h = set->mode ? set->mode->vdisplay : 0;
+	primary_state->crtc_w = set->mode ? set->mode->hdisplay : 0;
 	primary_state->src_x = set->x << 16;
 	primary_state->src_y = set->y << 16;
-	primary_state->src_h = set->mode->vdisplay << 16;
-	primary_state->src_w = set->mode->hdisplay << 16;
+	primary_state->src_h = set->mode ? set->mode->vdisplay << 16 : 0;
+	primary_state->src_w = set->mode ? set->mode->hdisplay << 16 : 0;
 
 commit:
 	ret = update_output_state(state, set);
@@ -2105,15 +2111,8 @@ drm_atomic_helper_crtc_duplicate_state(struct drm_crtc *crtc)
 	state->planes_changed = false;
 	state->event = NULL;
 
-	if (crtc->state->mode) {
-		state->mode =
-			drm_mode_duplicate(crtc->dev,
-			                   crtc->state->mode);
-		if (!state->mode) {
-			kfree(state);
-			state = NULL;
-		}
-	}
+	if (state->mode)
+		drm_mode_reference(state->mode);
 
 	return state;
 }
@@ -2130,7 +2129,7 @@ EXPORT_SYMBOL(drm_atomic_helper_crtc_duplicate_state);
 void drm_atomic_helper_crtc_destroy_state(struct drm_crtc *crtc,
 					  struct drm_crtc_state *state)
 {
-	kfree(state->mode);
+	drm_mode_destroy(crtc->dev, state->mode);
 	kfree(state);
 }
 EXPORT_SYMBOL(drm_atomic_helper_crtc_destroy_state);
-- 
2.3.2