[PATCH i-g-t 2/2] tests/kms_vrr: Add new test to validate LOBF

[Jeevan B <jeevan.b@intel.com>]

Validate refresh rate changes that appear to be stable but actually
change slightly in the VRR using the fixed refresh rate framework
for non-PSR scenarios.

v2: add PR check.
v3: update commit message and fix code structure.
v4: update logic using existing code.

Signed-off-by: Jeevan B <jeevan.b@intel.com>
---
 tests/kms_vrr.c | 57 +++++++++++++++++++++++++++++++++++++++++++++++--
 1 file changed, 55 insertions(+), 2 deletions(-)

diff --git a/tests/kms_vrr.c b/tests/kms_vrr.c
index 7e8885f16..851b8bbee 100644
--- a/tests/kms_vrr.c
+++ b/tests/kms_vrr.c
@@ -31,6 +31,7 @@
  */
 
 #include "igt.h"
+#include "igt_psr.h"
 #include "i915/intel_drrs.h"
 #include "sw_sync.h"
 #include <fcntl.h>
@@ -76,6 +77,11 @@
  * 		without a full modeset.
  * Functionality: LRR
  *
+ * SUBTEST: lobf
+ * Description: Test to validate link-off between active frames in non-psr
+ *              operation
+ * Functionality: LOBF
+ *
  * SUBTEST: max-min
  * Description: Oscillates between highest and lowest refresh each frame for
  *              manual flicker profiling
@@ -106,7 +112,8 @@ enum {
 	TEST_FASTSET = 1 << 7,
 	TEST_MAXMIN = 1 << 8,
 	TEST_CMRR = 1 << 9,
-	TEST_NEGATIVE = 1 << 10,
+	TEST_LINK_OFF = 1 << 10,
+	TEST_NEGATIVE = 1 << 11,
 };
 
 enum {
@@ -129,6 +136,7 @@ typedef struct vtest_ns {
 typedef struct data {
 	igt_display_t display;
 	int drm_fd;
+	int debugfs_fd;
 	igt_plane_t *primary;
 	igt_fb_t fb[2];
 	range_t range;
@@ -784,6 +792,27 @@ test_seamless_virtual_rr_basic(data_t *data, enum pipe pipe, igt_output_t *outpu
 	}
 }
 
+static void
+test_lobf(data_t *data, enum pipe pipe, igt_output_t *output, uint32_t flags)
+{
+	uint64_t rate[] = {0};
+
+	rate[0] = rate_from_refresh(data->switch_modes[HIGH_RR_MODE].vrefresh);
+	prepare_test(data, output, pipe);
+	data->debugfs_fd = igt_debugfs_dir(data->drm_fd);
+
+	igt_info("LOBF test execution on %s, PIPE %s with VRR range: (%u-%u) Hz\n",
+		 output->name, kmstest_pipe_name(pipe), data->range.min, data->range.max);
+
+	igt_output_override_mode(output, &data->switch_modes[HIGH_RR_MODE]);
+	flip_and_measure(data, output, pipe, rate, 1, TEST_DURATION_NS);
+	igt_output_override_mode(output, &data->switch_modes[LOW_RR_MODE]);
+	rate[0] = rate_from_refresh(data->switch_modes[LOW_RR_MODE].vrefresh);
+	flip_and_measure(data, output, pipe, rate, 1, NSECS_PER_SEC);
+	igt_assert_f(igt_get_i915_edp_lobf_status(data->drm_fd, output->name),
+		     "LOBF not enabled\n");
+}
+
 static void
 test_cmrr(data_t *data, enum pipe pipe, igt_output_t *output, uint32_t flags)
 {
@@ -843,6 +872,8 @@ static void test_cleanup(data_t *data, enum pipe pipe, igt_output_t *output)
 
 static bool output_constraint(data_t *data, igt_output_t *output, uint32_t flags)
 {
+	data->debugfs_fd = igt_debugfs_dir(data->drm_fd);
+
 	if ((flags & (TEST_SEAMLESS_VRR | TEST_SEAMLESS_DRRS | TEST_CMRR)) &&
 	    output->config.connector->connector_type != DRM_MODE_CONNECTOR_eDP)
 		return false;
@@ -852,6 +883,20 @@ static bool output_constraint(data_t *data, igt_output_t *output, uint32_t flags
 		igt_info("Selected panel won't support DRRS.\n");
 		return false;
 	}
+	if ((flags & TEST_LINK_OFF) &&
+	     output->config.connector->connector_type != DRM_MODE_CONNECTOR_eDP)
+		return false;
+
+	if ((flags & TEST_LINK_OFF) &&
+	    (psr_sink_support(data->drm_fd, data->debugfs_fd, PSR_MODE_1, NULL) ||
+	    psr_sink_support(data->drm_fd, data->debugfs_fd, PR_MODE, NULL)))
+		psr_disable(data->drm_fd, data->debugfs_fd, NULL);
+
+	if ((flags & TEST_LINK_OFF) &&
+		igt_get_i915_edp_lobf_status(data->drm_fd, output->name)) {
+		igt_info("LOBF not supported. \n");
+		return false;
+	}
 
 	/* Reset output */
 	igt_display_reset(&data->display);
@@ -1030,13 +1075,21 @@ igt_main_args("drs:", long_opts, help_str, opt_handler, &data)
 		igt_subtest_with_dynamic("seamless-rr-switch-virtual")
 			run_vrr_test(&data, test_seamless_virtual_rr_basic, TEST_SEAMLESS_VIRTUAL_RR);
 
-		igt_describe("Test to validate the the content rate exactly match with the "
+		igt_describe("Test to validate the content rate exactly match with the "
 			     "requested rate without any frame drops.");
 		igt_subtest_with_dynamic("cmrr") {
 			igt_require(intel_display_ver(intel_get_drm_devid(data.drm_fd)) >= 20);
 
 			run_vrr_test(&data, test_cmrr, TEST_CMRR);
 		}
+
+		igt_describe("Test to validate the link-off between active frames in "
+			     "non-PSR operation.");
+		igt_subtest_with_dynamic("lobf") {
+			igt_require(intel_display_ver(intel_get_drm_devid(data.drm_fd)) >= 20);
+
+			run_vrr_test(&data, test_lobf, TEST_LINK_OFF);
+		}
 	}
 
 	igt_fixture {
-- 
2.25.1