[PATCH 3/3] drm/amd/display: increase HDCP authentication delay

Bhawanpreet Lakha Bhawanpreet.Lakha at amd.com
Mon Mar 30 18:00:25 UTC 2020


[Why]
Some displays have an issue where the hdcp chips are initialized after the
display has already lit up. This means we can sometimes authentication too early
and cause authentication failures.

This happens when HDCP is enabled and the display is power cycled. Normally we
will authenticate 2 seconds after the display is lit, but some displays need a
bit more time.

[How]
Increase delay to 3 second before we start authentication.

Signed-off-by: Bhawanpreet Lakha <Bhawanpreet.Lakha at amd.com>
---
 drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_hdcp.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_hdcp.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_hdcp.c
index 39804d2df9df..78e1c11d4ae5 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_hdcp.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_hdcp.c
@@ -419,7 +419,7 @@ static void update_config(void *handle, struct cp_psp_stream_config *config)
 	link->dp.rev = aconnector->dc_link->dpcd_caps.dpcd_rev.raw;
 	link->dp.mst_supported = config->mst_supported;
 	display->adjust.disable = 1;
-	link->adjust.auth_delay = 2;
+	link->adjust.auth_delay = 3;
 	link->adjust.hdcp1.disable = 0;
 
 	hdcp_update_display(hdcp_work, link_index, aconnector, DRM_MODE_HDCP_CONTENT_TYPE0, false);
-- 
2.17.1



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