Commit ad1c59ad authored by Mario Limonciello (AMD)'s avatar Mario Limonciello (AMD) Committed by Alex Deucher
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drm/amd/display: Increase DPCD read retries 

[Why]
Empirical measurement of some monitors that fail to read EDID while
booting shows that the number of retries with a 30ms delay between
tries is as high as 16.

[How]
Increase number of retries to 20.

Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/4672


Reviewed-by: default avatarAlex Hung <alex.hung@amd.com>
Signed-off-by: default avatarMario Limonciello (AMD) <superm1@kernel.org>
Signed-off-by: default avatarIvan Lipski <ivan.lipski@amd.com>
Tested-by: default avatarDan Wheeler <daniel.wheeler@amd.com>
Signed-off-by: default avatarAlex Deucher <alexander.deucher@amd.com>
parent 669dca37

drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_capability.c

+1 −1
Original line number Diff line number Diff line
@@ -1713,7 +1713,7 @@ static bool retrieve_link_cap(struct dc_link *link) 
	union edp_configuration_cap edp_config_cap;

	union dp_downstream_port_present ds_port = { 0 };

	enum dc_status status = DC_ERROR_UNEXPECTED;

	uint32_t read_dpcd_retry_cnt = 3;

	uint32_t read_dpcd_retry_cnt = 20;

	int i;

	struct dp_sink_hw_fw_revision dp_hw_fw_revision;

	const uint32_t post_oui_delay = 30; // 30ms