[igt-dev] [v6 i-g-t 02/14] tests/kms_frontbuffer_tracking: Fix mode selection for 2x tests

[Bhanuprakash Modem]

This patch will find the connector/mode combination that fits
into the bandwidth when more than one monitor is connected.

Example:
  When two monitors connected through MST, the second monitor
  also tries to use the same mode. So two such modes may not
  fit into the link bandwidth. So, iterate through connected
  outputs & modes and find a combination of modes those fit
  into the link BW.

V2:
* Remove MST specific logic (Daniel)
V3:
* Add support for legacy commit (Ankit)
V4:
* Fix commit message (Ankit)

Cc: Imre Deak <imre.deak at intel.com>
Cc: Ankit Nautiyal <ankit.k.nautiyal at intel.com>
Cc: Daniel Vetter <daniel.vetter at ffwll.ch>
Signed-off-by: Bhanuprakash Modem <bhanuprakash.modem at intel.com>
Reviewed-by: Ankit Nautiyal <ankit.k.nautiyal at intel.com>
---
 tests/kms_frontbuffer_tracking.c | 40 ++++++++++++++++++++++++++++++++
 1 file changed, 40 insertions(+)

diff --git a/tests/kms_frontbuffer_tracking.c b/tests/kms_frontbuffer_tracking.c
index 2e74bec6f..65c2ddb5c 100644
--- a/tests/kms_frontbuffer_tracking.c
+++ b/tests/kms_frontbuffer_tracking.c
@@ -1683,14 +1683,54 @@ static void enable_prim_screen_and_wait(const struct test_mode *t)
 	do_assertions(ASSERT_NO_ACTION_CHANGE);
 }
 
+static void update_modeset_cached_params(void)
+{
+	bool found = false;
+
+	igt_output_set_pipe(prim_mode_params.output, prim_mode_params.pipe);
+	igt_output_set_pipe(scnd_mode_params.output, scnd_mode_params.pipe);
+
+	found = igt_override_all_active_output_modes_to_fit_bw(&drm.display);
+	igt_require_f(found, "No valid mode combo found.\n");
+
+	prim_mode_params.mode_copy = *igt_output_get_mode(prim_mode_params.output);
+	prim_mode_params.mode = &prim_mode_params.mode_copy;
+	prim_mode_params.primary.w = prim_mode_params.mode->hdisplay;
+	prim_mode_params.primary.h = prim_mode_params.mode->vdisplay;
+
+	scnd_mode_params.mode_copy = *igt_output_get_mode(scnd_mode_params.output);
+	scnd_mode_params.mode = &scnd_mode_params.mode_copy;
+	scnd_mode_params.primary.w = scnd_mode_params.mode->hdisplay;
+	scnd_mode_params.primary.h = scnd_mode_params.mode->vdisplay;
+
+	fill_fb_region(&prim_mode_params.primary, COLOR_PRIM_BG);
+	fill_fb_region(&scnd_mode_params.primary, COLOR_SCND_BG);
+
+	__set_mode_for_params(&prim_mode_params);
+	__set_mode_for_params(&scnd_mode_params);
+}
+
 static void enable_both_screens_and_wait(const struct test_mode *t)
 {
+	int ret;
+
 	fill_fb_region(&prim_mode_params.primary, COLOR_PRIM_BG);
 	fill_fb_region(&scnd_mode_params.primary, COLOR_SCND_BG);
 
 	__set_mode_for_params(&prim_mode_params);
 	__set_mode_for_params(&scnd_mode_params);
 
+	if (drm.display.is_atomic)
+		ret = igt_display_try_commit_atomic(&drm.display,
+				DRM_MODE_ATOMIC_TEST_ONLY |
+				DRM_MODE_ATOMIC_ALLOW_MODESET,
+				NULL);
+	else
+		ret = igt_display_try_commit2(&drm.display, COMMIT_LEGACY);
+
+	if (ret)
+		update_modeset_cached_params();
+
 	igt_display_commit2(&drm.display, drm.display.is_atomic ? COMMIT_ATOMIC : COMMIT_LEGACY);
 
 	wanted_crc = &blue_crcs[t->format].crc;
-- 
2.20.1