drm/amd/display: Add flag to modify MST delay

[Why]
Some panels may require more MST delay on discovery

[How]
Add panel patch and debug mst delay flag
Reviewed-by: Charlene Liu <Charlene.Liu@amd.com>
Acked-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: Duncan Ma <duncan.ma@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dc/dc.h

@@ -741,14 +741,15 @@ struct dc_debug_options {
 	bool enable_sw_cntl_psr;
 	union dpia_debug_options dpia_debug;
 	bool disable_fixed_vs_aux_timeout_wa;
-	uint32_t fixed_vs_aux_delay_config_wa;
 	bool force_disable_subvp;
 	bool force_subvp_mclk_switch;
 	bool force_usr_allow;
 	/* uses value at boot and disables switch */
 	bool disable_dtb_ref_clk_switch;
+	uint32_t fixed_vs_aux_delay_config_wa;
 	bool extended_blank_optimization;
 	union aux_wake_wa_options aux_wake_wa;
+	uint32_t mst_start_top_delay;
 	uint8_t psr_power_use_phy_fsm;
 	enum dml_hostvm_override_opts dml_hostvm_override;
 	bool use_legacy_soc_bb_mechanism;

drivers/gpu/drm/amd/display/dc/dc_types.h

@@ -199,6 +199,7 @@ struct dc_panel_patch {
 	unsigned int embedded_tiled_slave;
 	unsigned int disable_fams;
 	unsigned int skip_avmute;
+	unsigned int mst_start_top_delay;
 };
 
 struct dc_edid_caps {