[igt-dev] [PATCH i-g-t 2/4] tests/kms_psr_sink_crc: Do not test sink crc

[Dhinakaran Pandiyan]

eDP sink crc reads use vblank interrupts that cause PSR exit and
therefore makes them unsuitable for PSR testing. Besides that, reading
sink CRC via the AUX channel for testing when the HW also is most likely
is going to be using AUX channel is a recipe for inconsistent test
results. Thirdly, CRC's have been seen to be noisy/inconsistent across
sinks. We tradeoff the ability to validate what the sink is displaying
for correctness.

We also make use of source PSR status register to check whether HW tracking
triggered PSR exit upon an exit event.

Cc: Daniel Vetter <daniel at ffwll.ch>
Cc: Rodrigo Vivi <rodrigo.vivi at intel.com>
Signed-off-by: Dhinakaran Pandiyan <dhinakaran.pandiyan at intel.com>
---
 tests/kms_psr_sink_crc.c | 60 ++++++++++++------------------------------------
 1 file changed, 15 insertions(+), 45 deletions(-)

diff --git a/tests/kms_psr_sink_crc.c b/tests/kms_psr_sink_crc.c
index 3115a5de..4a18609a 100644
--- a/tests/kms_psr_sink_crc.c
+++ b/tests/kms_psr_sink_crc.c
@@ -28,12 +28,8 @@
 #include <stdbool.h>
 #include <stdio.h>
 #include <string.h>
-
 #include "intel_bufmgr.h"
 
-#define CRC_BLACK "000000000000"
-#define CRC_LEN 12
-
 enum operations {
 	PAGE_FLIP,
 	MMAP_GTT,
@@ -222,36 +218,17 @@ static bool wait_psr_entry(data_t *data)
 	return false;
 }
 
-static void get_sink_crc(data_t *data, char *crc)
+static bool psr_inactive(data_t *data)
 {
-	if (igt_interactive_debug)
-		return;
-
-	igt_require_f(igt_sysfs_read(data->debugfs_fd, "i915_sink_crc_eDP1",
-				     crc, CRC_LEN) == CRC_LEN,
-		      "Sink CRC is unreliable on this machine. Try manual debug with --interactive-debug=no-crc\n");
-	igt_debug("sink CRC: %.*s\n", CRC_LEN, crc);
-
-	/* Black screen is always invalid */
-	igt_assert(strncmp(crc, CRC_BLACK, CRC_LEN));
-}
+	char buf[512];
 
-static bool is_green(char *crc)
-{
-	const char *mask = "0000FFFF0000";
-	uint32_t *p = (uint32_t *)crc, *mask_p = (uint32_t *)mask;
-	if (igt_interactive_debug)
-		return false;
-
-	/* Check R and B components are 0 and G is non-zero */
-	return *p == *mask_p && *(p + 2) == *(mask_p + 2) &&
-	       (*(p + 1) & *(mask_p + 1)) != 0;
+	igt_debugfs_read(data->drm_fd, "i915_edp_psr_status", buf);
+	return !(strstr(buf, "SRDENT") || strstr("SLEEP"));
 }
 
-static void assert_or_manual(bool condition, const char *expected)
+static inline void manual(const char *expected)
 {
-	igt_debug_manual_check("no-crc", expected);
-	igt_assert(igt_interactive_debug || condition);
+	igt_debug_manual_check("all", expected);
 }
 
 static bool drrs_disabled(data_t *data)
@@ -268,39 +245,32 @@ static void run_test(data_t *data)
 	uint32_t handle = data->fb_white.gem_handle;
 	igt_plane_t *test_plane = data->test_plane;
 	void *ptr;
-	char ref_crc[CRC_LEN];
-	char crc[CRC_LEN];
 	const char *expected = "";
 
 	/* Confirm that screen became Green */
-	get_sink_crc(data, ref_crc);
-	assert_or_manual(is_green(ref_crc), "screen GREEN");
+	manual("screen GREEN");
 
 	/* Confirm screen stays Green after PSR got active */
 	igt_assert(wait_psr_entry(data));
-	get_sink_crc(data, ref_crc);
-	assert_or_manual(is_green(ref_crc), "screen GREEN");
+	manual("screen GREEN");
 
 	/* Setting a secondary fb/plane */
 	igt_plane_set_fb(test_plane, &data->fb_white);
 	igt_display_commit(&data->display);
 
 	/* Confirm it is not Green anymore */
-	igt_assert(wait_psr_entry(data));
-	get_sink_crc(data, ref_crc);
 	if (test_plane->type == DRM_PLANE_TYPE_PRIMARY)
-		assert_or_manual(!is_green(ref_crc), "screen WHITE");
+		manual("screen WHITE");
 	else
-		assert_or_manual(!is_green(ref_crc), "GREEN background with WHITE box");
+		manual("GREEN background with WHITE box");
 
+	igt_assert(wait_psr_entry(data));
 	switch (data->op) {
 	case PAGE_FLIP:
 		/* Only in use when testing primary plane */
 		igt_assert(drmModePageFlip(data->drm_fd, data->crtc_id,
 					   data->fb_green.fb_id, 0, NULL) == 0);
-		get_sink_crc(data, crc);
-		assert_or_manual(is_green(crc), "screen GREEN");
-		expected = "still GREEN";
+		expected = "GREEN";
 		break;
 	case MMAP_GTT:
 		ptr = gem_mmap__gtt(data->drm_fd, handle, data->mod_size,
@@ -342,8 +312,8 @@ static void run_test(data_t *data)
 		expected = "screen GREEN";
 		break;
 	}
-	get_sink_crc(data, crc);
-	assert_or_manual(strncmp(ref_crc, crc, CRC_LEN) != 0, expected);
+	assert(psr_inactive(data));
+	manual(expected);
 }
 
 static void test_cleanup(data_t *data) {
@@ -444,7 +414,7 @@ static int opt_handler(int opt, int opt_index, void *_data)
 int main(int argc, char *argv[])
 {
 	const char *help_str =
-	       "  --no-psr\tRun test without PSR to check the CRC test logic.";
+	       "  --no-psr\tRun test without PSR.";
 	static struct option long_options[] = {
 		{"no-psr", 0, 0, 'n'},
 		{ 0, 0, 0, 0 }
-- 
2.14.1