[igt-dev] [PATCH i-g-t] tests/kms_frontbuffer_tracking: Make sure GPU is quiescent before handling assertions, v2.

[Maarten Lankhorst]

Typically PSR enables in around 136 ms, but on some tests the we have
to explicitly make sure that the gpu is idle before rendering.

Otherwise, sometimes we wait for the background flusher to finish,
which will take at least a second longer, and causes the wait for
PSR to timeout.

On kms_frontbuffer_tracking:
Starting subtest: psr-2p-scndscrn-shrfb-plflip-blt
psr_active(debugfs_fd, true) took 136ms
psr_active(debugfs_fd, true) took 136ms
psr_active(debugfs_fd, true) took 350ms
psr_active(debugfs_fd, true) took 136ms
psr_active(debugfs_fd, true) took 1598ms

Changes since v1:
- Do not call gem_quiescent_gpu on modesetfrombusy subtest, or we get
  a timeout.

Cc: Dhinakaran Pandiyan <dhinakaran.pandiyan at intel.com>
Cc: José Roberto de Souza <jose.souza at intel.com>
Cc: Chris Wilson <chris at chris-wilson.co.uk>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=108733
Suggested-by: Chris Wilson <chris at chris-wilson.co.uk>
Reviewed-by: Daniel Vetter <daniel.vetter at ffwll.ch> #v1
---
 tests/kms_frontbuffer_tracking.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/tests/kms_frontbuffer_tracking.c b/tests/kms_frontbuffer_tracking.c
index 276ef83ce386..5ab283197685 100644
--- a/tests/kms_frontbuffer_tracking.c
+++ b/tests/kms_frontbuffer_tracking.c
@@ -1551,9 +1551,11 @@ static void do_flush(const struct test_mode *t)
 
 #define DRRS_ASSERT_FLAGS		(7 << 8)
 #define ASSERT_DRRS_HIGH		(1 << 8)
-#define ASSERT_DRRS_LOW		(1 << 9)
+#define ASSERT_DRRS_LOW			(1 << 9)
 #define ASSERT_DRRS_INACTIVE		(1 << 10)
 
+#define ASSERT_NO_IDLE_GPU		(1 << 11)
+
 static int adjust_assertion_flags(const struct test_mode *t, int flags)
 {
 	if (!(flags & DONT_ASSERT_FEATURE_STATUS)) {
@@ -1642,6 +1644,10 @@ static void __do_assertions(const struct test_mode *t, int flags,
 {
 	flags = adjust_assertion_flags(t, flags);
 
+	/* Make sure any submitted rendering is now idle. */
+	if (!(flags & ASSERT_NO_IDLE_GPU))
+		gem_quiescent_gpu(drm.fd);
+
 	igt_debug("checking asserts in line %i\n", line);
 
 	wait_user(2, "Paused before assertions.");
@@ -2691,7 +2697,7 @@ static void modesetfrombusy_subtest(const struct test_mode *t)
 	params->primary.fb = &fb2;
 	set_mode_for_params(params);
 
-	do_assertions(0);
+	do_assertions(ASSERT_NO_IDLE_GPU);
 
 	stop_busy_thread();
 
-- 
2.19.2