[PATCH 3/3] [i-g-t] tests/amdgpu/amd_ilr: Fix psr edp rx crc read timeout

[Hersen Wu <hersenxs.wu@amd.com>]

With debugfs disallow_edp_enter_psr, disable edp
psr before tx read rx crc.

With set_all_output_pipe_to_none of test_init,
tx write dpcd 0x600=2. this will let dpcd 0x170=0.
rx psr and crc check for rx internal logic are disabled.
with disallow_edp_enter_psr, when set test patterns
are committed by igt_display_commit_atomic, kernel
driver will turn on edp with dpcd 0x170=0. then tx
read rx crc successfully.

Signed-off-by: Hersen Wu <hersenxs.wu@amd.com>
---
 tests/amdgpu/amd_ilr.c | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/tests/amdgpu/amd_ilr.c b/tests/amdgpu/amd_ilr.c
index b2c0f294d..8e892738f 100644
--- a/tests/amdgpu/amd_ilr.c
+++ b/tests/amdgpu/amd_ilr.c
@@ -205,11 +205,31 @@ static void test_flow(data_t *data, enum sub_test option)
 			continue;
 		}
 
+		/* igt_amd_output_has_ilr_setting check if debugfs exist,
+		 * but ilr settings could be all 0s -- not supported.
+		 * need check if ilr settings values are supported.
+		 */
+		igt_amd_read_ilr_setting(data->drm_fd, output->name, data->supported_ilr);
+		if (data->supported_ilr[0] == 0)
+			continue;
+
 		igt_info("Testing on output: %s\n", output->name);
 
 		/* Init only if display supports ilr link settings */
 		test_init(data, output);
 
+		/* with set_all_output_pipe_to_none within test_init,
+		 * kernel driver tx write dpcd 0x600=2 to rx. edp rx
+		 * exit psr state and stop verify crc from main link.
+		 * with disable edp enter psr within kernel, when run
+		 * set test pattern, display is turned on. kernel driver
+		 * tx will not notify rx psr enable and crc checking by
+		 * rx. by this, when tx want to read crc from rx, rx will
+		 * check crc and response right away. timeout will not
+		 * happens.
+		 */
+		igt_amd_disallow_edp_enter_psr(data->drm_fd, output->name, true);
+
 		mode = igt_output_get_mode(output);
 		igt_assert(mode);
 
@@ -243,6 +263,9 @@ static void test_flow(data_t *data, enum sub_test option)
 		igt_remove_fb(data->drm_fd, &data->fb);
 
 		test_fini(data);
+
+		/* restore allow kernel driver eDP PSR */
+		igt_amd_disallow_edp_enter_psr(data->drm_fd, output->name, false);
 	}
 
 }
-- 
2.25.1