[Intel-gfx] [PATCH 01/11] HAX to make DSC work on the icelake test system

[Maarten Lankhorst]

DSC is available on the display emulator, but not set in DPCD.
Override the entries to allow bigjoiner testing.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst at linux.intel.com>
---
 drivers/gpu/drm/drm_dp_helper.c | 4 ++--
 include/drm/drm_dp_helper.h     | 1 +
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c
index 2c7870aef469..3d6038f35ea2 100644
--- a/drivers/gpu/drm/drm_dp_helper.c
+++ b/drivers/gpu/drm/drm_dp_helper.c
@@ -1261,7 +1261,7 @@ u8 drm_dp_dsc_sink_max_slice_count(const u8 dsc_dpcd[DP_DSC_RECEIVER_CAP_SIZE],
 		if (slice_cap1 & DP_DSC_4_PER_DP_DSC_SINK)
 			return 4;
 		if (slice_cap1 & DP_DSC_2_PER_DP_DSC_SINK)
-			return 2;
+			return 4;
 		if (slice_cap1 & DP_DSC_1_PER_DP_DSC_SINK)
 			return 1;
 	} else {
@@ -1285,7 +1285,7 @@ u8 drm_dp_dsc_sink_max_slice_count(const u8 dsc_dpcd[DP_DSC_RECEIVER_CAP_SIZE],
 		if (slice_cap1 & DP_DSC_4_PER_DP_DSC_SINK)
 			return 4;
 		if (slice_cap1 & DP_DSC_2_PER_DP_DSC_SINK)
-			return 2;
+			return 4;
 		if (slice_cap1 & DP_DSC_1_PER_DP_DSC_SINK)
 			return 1;
 	}
diff --git a/include/drm/drm_dp_helper.h b/include/drm/drm_dp_helper.h
index 51ecb5112ef8..2ebd7feffd90 100644
--- a/include/drm/drm_dp_helper.h
+++ b/include/drm/drm_dp_helper.h
@@ -1270,6 +1270,7 @@ int drm_dp_dsc_sink_supported_input_bpcs(const u8 dsc_dpc[DP_DSC_RECEIVER_CAP_SI
 static inline bool
 drm_dp_sink_supports_dsc(const u8 dsc_dpcd[DP_DSC_RECEIVER_CAP_SIZE])
 {
+	return dsc_dpcd[DP_DSC_REV - DP_DSC_SUPPORT];
 	return dsc_dpcd[DP_DSC_SUPPORT - DP_DSC_SUPPORT] &
 		DP_DSC_DECOMPRESSION_IS_SUPPORTED;
 }
-- 
2.24.0