drm/atomic: Save flip flags in drm_crtc_state

Allows using atomic flip helpers for drivers
using ASYNC flip.
Remove ASYNC_FLIP restriction in helpers and
caches the page flip flags in drm_crtc_state
to be used in the low level drivers.

v2:
Resending the patch since the original was broken.

v3:
Save flag in crtc_state instead of plane_state

v4:
Reset the flag before using again.

v5:
Fix type in header.
Rename the field to pageflip_flags.
Remove unrelated hunk.
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Andrey Grodzovsky <Andrey.Grodzovsky@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1486072591-3893-2-git-send-email-Andrey.Grodzovsky@amd.com

drivers/gpu/drm/drm_atomic_helper.c

@@ -2718,7 +2718,8 @@ static int page_flip_common(
 				struct drm_atomic_state *state,
 				struct drm_crtc *crtc,
 				struct drm_framebuffer *fb,
-				struct drm_pending_vblank_event *event)
+				struct drm_pending_vblank_event *event,
+				uint32_t flags)
 {
 	struct drm_plane *plane = crtc->primary;
 	struct drm_plane_state *plane_state;
@@ -2730,12 +2731,12 @@ static int page_flip_common(
 		return PTR_ERR(crtc_state);
 
 	crtc_state->event = event;
+	crtc_state->pageflip_flags = flags;
 
 	plane_state = drm_atomic_get_plane_state(state, plane);
 	if (IS_ERR(plane_state))
 		return PTR_ERR(plane_state);
 
-
 	ret = drm_atomic_set_crtc_for_plane(plane_state, crtc);
 	if (ret != 0)
 		return ret;
@@ -2762,10 +2763,6 @@ static int page_flip_common(
  * Provides a default &drm_crtc_funcs.page_flip implementation
  * using the atomic driver interface.
  *
- * Note that for now so called async page flips (i.e. updates which are not
- * synchronized to vblank) are not supported, since the atomic interfaces have
- * no provisions for this yet.
- *
  * Returns:
  * Returns 0 on success, negative errno numbers on failure.
  *
@@ -2781,9 +2778,6 @@ int drm_atomic_helper_page_flip(struct drm_crtc *crtc,
 	struct drm_atomic_state *state;
 	int ret = 0;
 
-	if (flags & DRM_MODE_PAGE_FLIP_ASYNC)
-		return -EINVAL;
-
 	state = drm_atomic_state_alloc(plane->dev);
 	if (!state)
 		return -ENOMEM;
@@ -2791,7 +2785,7 @@ int drm_atomic_helper_page_flip(struct drm_crtc *crtc,
 	state->acquire_ctx = drm_modeset_legacy_acquire_ctx(crtc);
 
 retry:
-	ret = page_flip_common(state, crtc, fb, event);
+	ret = page_flip_common(state, crtc, fb, event, flags);
 	if (ret != 0)
 		goto fail;
 
@@ -2846,9 +2840,6 @@ int drm_atomic_helper_page_flip_target(
 	struct drm_crtc_state *crtc_state;
 	int ret = 0;
 
-	if (flags & DRM_MODE_PAGE_FLIP_ASYNC)
-		return -EINVAL;
-
 	state = drm_atomic_state_alloc(plane->dev);
 	if (!state)
 		return -ENOMEM;
@@ -2856,7 +2847,7 @@ int drm_atomic_helper_page_flip_target(
 	state->acquire_ctx = drm_modeset_legacy_acquire_ctx(crtc);
 
 retry:
-	ret = page_flip_common(state, crtc, fb, event);
+	ret = page_flip_common(state, crtc, fb, event, flags);
 	if (ret != 0)
 		goto fail;
 
@@ -3056,6 +3047,7 @@ void __drm_atomic_helper_crtc_duplicate_state(struct drm_crtc *crtc,
 	state->color_mgmt_changed = false;
 	state->zpos_changed = false;
 	state->event = NULL;
+	state->pageflip_flags = 0;
 }
 EXPORT_SYMBOL(__drm_atomic_helper_crtc_duplicate_state);
 

include/drm/drm_crtc.h

@@ -155,9 +155,16 @@ struct drm_crtc_state {
 	 * Target vertical blank period when a page flip
 	 * should take effect.
 	 */
-
 	u32 target_vblank;
 
+	/**
+	 * @pageflip_flags:
+	 *
+	 * DRM_MODE_PAGE_FLIP_* flags, as passed to the page flip ioctl.
+	 * Zero in any other case.
+	 */
+	u32 pageflip_flags;
+
 	/**
 	 * @event:
 	 *