[igt-dev] [PATCH i-g-t v4 2/2] igt/tests/kms_atomic_transition: Tolerate if can't have all planes

[Stanislav Lisovskiy]

With some upcoming changes i915 might not allow
all sprite planes enabled, depending on available
bandwidth limitation. Thus the test need to decrement
amount of planes and try again, instead of panicking.

v2: Removed excessive nested conditions, making code a bit
    more readable(hopefully). Stopped using global n_planes
    variable as it might cause resources being unreleased.
    Using now parms[i].mask as a way to determine if plane
    has to be included into commit.

Signed-off-by: Stanislav Lisovskiy <stanislav.lisovskiy at intel.com>
---
 tests/kms_atomic_transition.c | 105 +++++++++++++++++-----------------
 1 file changed, 54 insertions(+), 51 deletions(-)

diff --git a/tests/kms_atomic_transition.c b/tests/kms_atomic_transition.c
index 638fe17e..ee07880e 100644
--- a/tests/kms_atomic_transition.c
+++ b/tests/kms_atomic_transition.c
@@ -214,7 +214,9 @@ static void setup_parms(igt_display_t *display, enum pipe pipe,
 	uint32_t n_planes = display->pipes[pipe].n_planes;
 	uint32_t n_overlays = 0, overlays[n_planes];
 	igt_plane_t *plane;
-	uint32_t iter_mask = 3;
+	uint32_t iter_mask;
+	int retries = n_planes - 1;
+	int ret = 0;
 
 	do_or_die(drmGetCap(display->drm_fd, DRM_CAP_CURSOR_WIDTH, &cursor_width));
 	if (cursor_width >= mode->hdisplay)
@@ -224,6 +226,10 @@ static void setup_parms(igt_display_t *display, enum pipe pipe,
 	if (cursor_height >= mode->vdisplay)
 		cursor_height = mode->vdisplay;
 
+retry:
+	n_overlays = 0;
+	iter_mask = 3;
+
 	for_each_plane_on_pipe(display, pipe, plane) {
 		int i = plane->index;
 
@@ -238,12 +244,16 @@ static void setup_parms(igt_display_t *display, enum pipe pipe,
 			parms[i].height = cursor_height;
 			parms[i].mask = 1 << 1;
 		} else {
-			parms[i].fb = sprite_fb;
-			parms[i].mask = 1 << 2;
-
-			iter_mask |= 1 << 2;
-
-			overlays[n_overlays++] = i;
+			if (n_overlays < (n_planes - 2)) {
+				parms[i].fb = sprite_fb;
+				parms[i].mask = 1 << 2;
+				iter_mask |= 1 << 2;
+				overlays[n_overlays++] = i;
+			}
+			else {
+				parms[i].fb = NULL;
+				parms[i].mask = 0;
+			}
 		}
 	}
 
@@ -278,16 +288,13 @@ static void setup_parms(igt_display_t *display, enum pipe pipe,
 	 * Pre gen9 not all sizes are supported, find the biggest possible
 	 * size that can be enabled on all sprite planes.
 	 */
-retry:
 	prev_w = sprite_width = cursor_width;
 	prev_h = sprite_height = cursor_height;
 
 	max_sprite_width = (sprite_width == mode->hdisplay);
 	max_sprite_height = (sprite_height == mode->vdisplay);
 
-	while (1) {
-		int ret;
-
+	while (!max_sprite_width && !max_sprite_height) {
 		set_sprite_wh(display, pipe, parms, sprite_fb,
 			      alpha, sprite_width, sprite_height);
 
@@ -295,54 +302,49 @@ retry:
 		ret = igt_display_try_commit_atomic(display, DRM_MODE_ATOMIC_TEST_ONLY | DRM_MODE_ATOMIC_ALLOW_MODESET, NULL);
 		igt_assert(!is_atomic_check_failure_errno(ret));
 
-		if (is_atomic_check_plane_size_errno(ret)) {
-			if (cursor_width == sprite_width &&
-			    cursor_height == sprite_height) {
-				igt_assert_f(alpha,
-					      "Cannot configure the test with all sprite planes enabled\n");
-
-				/* retry once with XRGB format. */
-				alpha = false;
-				goto retry;
-			}
-
-			sprite_width = prev_w;
-			sprite_height = prev_h;
-
-			if (max_sprite_width && max_sprite_height) {
-				set_sprite_wh(display, pipe, parms, sprite_fb,
-					      alpha, sprite_width, sprite_height);
-				break;
-			}
-
-			if (!max_sprite_width)
-				max_sprite_width = true;
-			else
-				max_sprite_height = true;
-		} else {
+		if (!is_atomic_check_plane_size_errno(ret)) {
 			prev_w = sprite_width;
 			prev_h = sprite_height;
-		}
-
-		if (!max_sprite_width) {
-			sprite_width *= 2;
-
+    
+			sprite_width *= max_sprite_width ? 1 : 2;
 			if (sprite_width >= mode->hdisplay) {
 				max_sprite_width = true;
-
 				sprite_width = mode->hdisplay;
 			}
-		} else if (!max_sprite_height) {
-			sprite_height *= 2;
 
+			sprite_height *= max_sprite_height ? 1 : 2;
 			if (sprite_height >= mode->vdisplay) {
 				max_sprite_height = true;
-
 				sprite_height = mode->vdisplay;
 			}
-		} else
-			/* Max sized sprites for all! */
-			break;
+			continue;
+		}
+
+		if (cursor_width == sprite_width &&
+		    cursor_height == sprite_height) {
+			igt_assert_f(retries > 0,
+				      "Cannot configure the test with all sprite planes enabled\n");
+			--retries;
+			/* retry once with XRGB format. */
+			if (alpha) {
+				alpha = false;
+				igt_warn("Removed alpha\n");
+			}
+			else {
+				igt_assert_f(n_planes > 1, "No planes left to proceed with!");
+				n_planes--;
+				igt_warn("Reduced available planes to %d\n", n_planes);
+			}
+			goto retry;
+		}
+
+		sprite_width = prev_w;
+		sprite_height = prev_h;
+
+		if (!max_sprite_width)
+			max_sprite_width = true;
+		else
+			max_sprite_height = true;
 	}
 
 	igt_info("Running test on pipe %s with resolution %dx%d and sprite size %dx%d alpha %i\n",
@@ -463,7 +465,6 @@ run_transition_test(igt_display_t *display, enum pipe pipe, igt_output_t *output
 
 	if (flags & DRM_MODE_ATOMIC_ALLOW_MODESET) {
 		igt_output_set_pipe(output, PIPE_NONE);
-
 		igt_display_commit2(display, COMMIT_ATOMIC);
 
 		igt_output_set_pipe(output, pipe);
@@ -525,8 +526,10 @@ run_transition_test(igt_display_t *display, enum pipe pipe, igt_output_t *output
 		}
 
 		/* force planes to be part of commit */
-		for_each_plane_on_pipe(display, pipe, plane)
-			igt_plane_set_position(plane, 0, 0);
+		for_each_plane_on_pipe(display, pipe, plane) {
+			if (parms[plane->index].mask)
+				igt_plane_set_position(plane, 0, 0);
+		}
 
 		igt_display_commit2(display, COMMIT_ATOMIC);
 
-- 
2.17.1