[igt-dev] [PATCH i-g-t 18/20] tests/psr: Check for timestamp support

[Dhinakaran Pandiyan]

BDW+ have PSR interrupts from which the kernel can update exit and
pre-entry time stamps. Tests should prefer this over sink crc to
validate PSR.

Signed-off-by: Dhinakaran Pandiyan <dhinakaran.pandiyan at intel.com>
---
 tests/kms_psr_sink_crc.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/tests/kms_psr_sink_crc.c b/tests/kms_psr_sink_crc.c
index 043b9e38..147b492f 100644
--- a/tests/kms_psr_sink_crc.c
+++ b/tests/kms_psr_sink_crc.c
@@ -75,6 +75,7 @@ typedef struct {
 	igt_output_t *output;
 	bool with_psr_disabled;
 	bool with_sink_crc;
+	bool with_timestamps;
 } data_t;
 
 static void create_cursor_fb(data_t *data)
@@ -200,6 +201,17 @@ static bool sink_support(data_t *data)
 		strstr(buf, "Sink_Support: yes\n");
 }
 
+static void timestamp_support(data_t *data)
+{
+	char buf[512];
+
+	igt_sysfs_set(data->debugfs_fd, "i915_edp_psr_debug", "1");
+	igt_debugfs_read(data->drm_fd, "i915_edp_psr_status", buf);
+	data->with_timestamps = strstr(buf, "Last exit at:");
+	igt_debug("Time stamp support %d\n", data->with_timestamps);
+	igt_sysfs_set(data->debugfs_fd, "i915_edp_psr_debug", "0");
+}
+
 static bool psr_enabled(data_t *data)
 {
 	char buf[512];
@@ -500,6 +512,7 @@ int main(int argc, char *argv[])
 					 0 : 1);
 		igt_require_f(sink_support(&data),
 			      "Sink does not support PSR\n");
+		timestamp_support(&data);
 
 		data.bufmgr = drm_intel_bufmgr_gem_init(data.drm_fd, 4096);
 		igt_assert(data.bufmgr);
-- 
2.14.1