[igt-dev] [[PATCH i-g-t]] tests/kms_setmode: disable DRRS if eDP support variable refresh rate

[Lee Shawn C]

Below is a failed case while testing kms_setmode.

CRTC[80] [Pipe A] Mode: 1920x1200 at 60Hz Connectors: eDP-1[236]
Expected frametime: 16659us; measured 20824.4us +- 4.799us accuracy 0.01% [0.10 scanlines]

The expected frame time is 16659us (60Hz refresh rate).
But kms_setmode report measured time was 20824.4us (48Hz) then
it failed. We found legacy DRRS mode was active at that time
then refresh rate fall into lower RR automatically to cause this problem.
Disable DRRS after crtc setmode can avoid driver switch to lower RR mode
and get pass for this test as well.

Issue: https://gitlab.freedesktop.org/drm/igt-gpu-tools/-/issues/148
Cc: Tvrtko Ursulin <tvrtko.ursulin at linux.intel.com>
Cc: Vidya Srinivas <vidya.srinivas at intel.com>
Signed-off-by: Lee Shawn C <shawn.c.lee at intel.com>
---
 tests/kms_setmode.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/tests/kms_setmode.c b/tests/kms_setmode.c
index 5fc4421c0080..b6fe3f9c159a 100644
--- a/tests/kms_setmode.c
+++ b/tests/kms_setmode.c
@@ -31,6 +31,7 @@
 #include <sys/time.h>
 #include <math.h>
 #include "xe/xe_query.h"
+#include "i915/intel_drrs.h"
 /**
  * TEST: kms setmode
  * Category: Display
@@ -651,6 +652,9 @@ retry:
 					     crtc->fb_info.fb_id, 0, 0, ids,
 					     crtc->connector_count, &crtc->mode);
 
+		if (is_intel_device(drm_fd))
+			intel_drrs_disable(drm_fd, crtc->pipe_id);
+
 		free(ids);
 
 		if (ret < 0) {
-- 
2.34.1