[i-g-t 1/2] tests/amdgpu/amd_dp_dsc: Do not disable DSC for high bw panels

[George Zhang <george.zhang@amd.com>]

The test previously attempted to disable DSC even on high bandwidth
panels. This would erroneously fail the dsc_enable test even though DSC
is on.

Fix this by checking what mode the panel defaults to when set to
automatic. If DSC is on, then do not attempt to force it off later.

Signed-off-by: George Zhang <george.zhang@amd.com>
---
 tests/amdgpu/amd_dp_dsc.c | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/tests/amdgpu/amd_dp_dsc.c b/tests/amdgpu/amd_dp_dsc.c
index dc71e903e..ccaf64c66 100644
--- a/tests/amdgpu/amd_dp_dsc.c
+++ b/tests/amdgpu/amd_dp_dsc.c
@@ -137,6 +137,9 @@ static void test_dsc_enable(data_t *data)
 		igt_output_set_crtc(output,
 				    crtc);
 		igt_plane_set_fb(data->primary[crtc->crtc_index], &ref_fb);
+
+		/* Make sure we are in automatic mode before we start*/
+		igt_amd_write_dsc_clock_en(data->fd, output->name, DSC_AUTOMATIC);
 		igt_display_commit_atomic(display, DRM_MODE_ATOMIC_ALLOW_MODESET, 0);

 		test_conn_cnt++;
@@ -154,7 +157,9 @@ static void test_dsc_enable(data_t *data)
 		dsc_on = igt_amd_read_dsc_clock_status(data->fd, output->name) == 1;

 		/* Revert DSC to automatic state */
-		igt_amd_write_dsc_clock_en(data->fd, output->name, DSC_FORCE_OFF);
+		if (!dsc_before)
+			/* We can only force off if the panel allows it. If DSC was on in automatic mode, we cannot force it off. */
+			igt_amd_write_dsc_clock_en(data->fd, output->name, DSC_FORCE_OFF);

 		igt_plane_set_fb(data->primary[crtc->crtc_index], &ref_fb);
 		igt_display_commit_atomic(display, DRM_MODE_ATOMIC_ALLOW_MODESET, NULL);
@@ -286,6 +291,7 @@ static void test_dsc_slice_dimensions_change(data_t *data)
 		igt_output_set_crtc(output,
 				    crtc);
 		igt_plane_set_fb(data->primary[crtc->crtc_index], &ref_fb);
+		igt_amd_write_dsc_clock_en(data->fd, output->name, DSC_AUTOMATIC);
 		igt_display_commit_atomic(display, DRM_MODE_ATOMIC_ALLOW_MODESET, 0);

 		test_conn_cnt++;
@@ -317,7 +323,8 @@ static void test_dsc_slice_dimensions_change(data_t *data)
 		}

 		/* Force disable DSC */
-		igt_amd_write_dsc_clock_en(data->fd, output->name, DSC_FORCE_OFF);
+		if (!dsc_before)
+			igt_amd_write_dsc_clock_en(data->fd, output->name, DSC_FORCE_OFF);

 		igt_plane_set_fb(data->primary[crtc->crtc_index], &ref_fb);
 		igt_display_commit_atomic(display, DRM_MODE_ATOMIC_ALLOW_MODESET, NULL);
--
2.55.0