drm/amd/display: Remove page_fleep_needed function.

This function makes a lot of assumptions to try and deduce
tha an atomic_commit came from FLIP ioctl. Those assumptions
are not explicit contract with DRM API and might lead to wrong
result as the code changes. Instead use drm_atomic_state.allow_modeset
flag which explicitly is set to false only in atomic flip
helper function, otherwise this flag is always true.
P.S When we get to do actual atomic IOCTL this will have to be revised
with the atomic call behavior.

Signed-off-by: Andrey Grodzovsky <Andrey.Grodzovsky@amd.com>
Acked-by: Harry Wentland <Harry.Wentland@amd.com>
Reviewed-by: Tony Cheng <Tony.Cheng@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_types.c

@@ -1429,80 +1429,6 @@ static const struct drm_plane_funcs dm_plane_funcs = {
 	.atomic_destroy_state = drm_atomic_helper_plane_destroy_state
 };
 
-static void clear_unrelated_fields(struct drm_plane_state *state)
-{
-	state->crtc = NULL;
-	state->fb = NULL;
-	state->state = NULL;
-	state->fence = NULL;
-}
-
-/*TODO update because event is always present now */
-static bool page_flip_needed(
-	const struct drm_plane_state *new_state,
-	const struct drm_plane_state *old_state,
-	struct drm_pending_vblank_event *event,
-	bool commit_surface_required)
-{
-	struct drm_plane_state old_state_tmp;
-	struct drm_plane_state new_state_tmp;
-
-	struct amdgpu_framebuffer *amdgpu_fb_old;
-	struct amdgpu_framebuffer *amdgpu_fb_new;
-	struct amdgpu_crtc *acrtc_new;
-
-	uint64_t old_tiling_flags;
-	uint64_t new_tiling_flags;
-
-	bool page_flip_required;
-
-	if (!old_state)
-		return false;
-
-	if (!old_state->fb)
-		return false;
-
-	if (!new_state)
-		return false;
-
-	if (!new_state->fb)
-		return false;
-
-	old_state_tmp = *old_state;
-	new_state_tmp = *new_state;
-
-	if (!event)
-		return false;
-
-	amdgpu_fb_old = to_amdgpu_framebuffer(old_state->fb);
-	amdgpu_fb_new = to_amdgpu_framebuffer(new_state->fb);
-
-	if (!get_fb_info(amdgpu_fb_old, &old_tiling_flags, NULL))
-		return false;
-
-	if (!get_fb_info(amdgpu_fb_new, &new_tiling_flags, NULL))
-		return false;
-
-	if (commit_surface_required == true &&
-	    old_tiling_flags != new_tiling_flags)
-		return false;
-
-	clear_unrelated_fields(&old_state_tmp);
-	clear_unrelated_fields(&new_state_tmp);
-
-	page_flip_required = memcmp(&old_state_tmp,
-				    &new_state_tmp,
-				    sizeof(old_state_tmp)) == 0 ? true:false;
-
-	if (new_state->crtc && page_flip_required == false) {
-		acrtc_new = to_amdgpu_crtc(new_state->crtc);
-		if (acrtc_new->flip_flags & DRM_MODE_PAGE_FLIP_ASYNC)
-			page_flip_required = true;
-	}
-
-	return page_flip_required;
-}
-
 static int dm_plane_helper_prepare_fb(
 	struct drm_plane *plane,
 	struct drm_plane_state *new_state)
@@ -2477,11 +2403,7 @@ void amdgpu_dm_atomic_commit_tail(
 		 * 1. This commit is not a page flip.
 		 * 2. This commit is a page flip, and streams are created.
 		 */
-		pflip_needed = !state->allow_modeset &&
-				page_flip_needed(
-				plane_state,
-				old_plane_state,
-				crtc->state->event, true);
+		pflip_needed = !state->allow_modeset;
 		if (!pflip_needed ||
 		     action == DM_COMMIT_ACTION_DPMS_ON ||
 		     action == DM_COMMIT_ACTION_SET) {
@@ -2540,12 +2462,7 @@ void amdgpu_dm_atomic_commit_tail(
 		if (!fb || !crtc || !crtc->state->planes_changed ||
 			!crtc->state->active)
 			continue;
-		pflip_needed = !state->allow_modeset &&
-				page_flip_needed(
-				plane_state,
-				old_plane_state,
-				crtc->state->event,
-				false);
+		pflip_needed = !state->allow_modeset;
 
 		if (pflip_needed) {
 			amdgpu_dm_do_flip(
@@ -2927,7 +2844,6 @@ int amdgpu_dm_atomic_check(struct drm_device *dev,
 
 	for (i = 0; i < set_count; i++) {
 		for_each_plane_in_state(state, plane, plane_state, j) {
-			struct drm_plane_state *old_plane_state = plane->state;
 			struct drm_crtc *crtc = plane_state->crtc;
 			struct drm_framebuffer *fb = plane_state->fb;
 			struct drm_connector *connector;
@@ -2948,9 +2864,7 @@ int amdgpu_dm_atomic_check(struct drm_device *dev,
 			 * 2. This commit is a page flip, and streams are created.
 			 */
 			crtc_state = drm_atomic_get_crtc_state(state, crtc);
-			pflip_needed = !state->allow_modeset &&
-					page_flip_needed(plane_state, old_plane_state,
-					crtc_state->event, true);
+			pflip_needed = !state->allow_modeset;
 			if (!pflip_needed ||
 				action == DM_COMMIT_ACTION_DPMS_ON ||
 				action == DM_COMMIT_ACTION_SET) {