[PATCH 12/16] drm/amd/display: Create a temporary scratch dc_link

Aurabindo Pillai aurabindo.pillai at amd.com
Wed Mar 19 17:55:17 UTC 2025


From: Aric Cyr <Aric.Cyr at amd.com>

Create a temporary scratch dc_link for programming purposes
and fix a copy of pipe_ctx on the stack to a pointer reference.

Reviewed-by: Josip Pavic <josip.pavic at amd.com>
Signed-off-by: Aric Cyr <Aric.Cyr at amd.com>
Signed-off-by: Aurabindo Pillai <aurabindo.pillai at amd.com>
---
 drivers/gpu/drm/amd/display/dc/dc.h           | 329 +++++++++---------
 .../gpu/drm/amd/display/dc/inc/core_types.h   |   2 +-
 .../link/protocols/link_edp_panel_control.c   |   8 +-
 3 files changed, 170 insertions(+), 169 deletions(-)

diff --git a/drivers/gpu/drm/amd/display/dc/dc.h b/drivers/gpu/drm/amd/display/dc/dc.h
index be2518e07c14..13f3a8370592 100644
--- a/drivers/gpu/drm/amd/display/dc/dc.h
+++ b/drivers/gpu/drm/amd/display/dc/dc.h
@@ -1419,6 +1419,170 @@ struct dc_scratch_space {
 	struct dc_stream_state stream_state;
 };
 
+/*
+ * A link contains one or more sinks and their connected status.
+ * The currently active signal type (HDMI, DP-SST, DP-MST) is also reported.
+ */
+ struct dc_link {
+	struct dc_sink *remote_sinks[MAX_SINKS_PER_LINK];
+	unsigned int sink_count;
+	struct dc_sink *local_sink;
+	unsigned int link_index;
+	enum dc_connection_type type;
+	enum signal_type connector_signal;
+	enum dc_irq_source irq_source_hpd;
+	enum dc_irq_source irq_source_hpd_rx;/* aka DP Short Pulse  */
+
+	bool is_hpd_filter_disabled;
+	bool dp_ss_off;
+
+	/**
+	 * @link_state_valid:
+	 *
+	 * If there is no link and local sink, this variable should be set to
+	 * false. Otherwise, it should be set to true; usually, the function
+	 * core_link_enable_stream sets this field to true.
+	 */
+	bool link_state_valid;
+	bool aux_access_disabled;
+	bool sync_lt_in_progress;
+	bool skip_stream_reenable;
+	bool is_internal_display;
+	/** @todo Rename. Flag an endpoint as having a programmable mapping to a DIG encoder. */
+	bool is_dig_mapping_flexible;
+	bool hpd_status; /* HPD status of link without physical HPD pin. */
+	bool is_hpd_pending; /* Indicates a new received hpd */
+
+	/* USB4 DPIA links skip verifying link cap, instead performing the fallback method
+	 * for every link training. This is incompatible with DP LL compliance automation,
+	 * which expects the same link settings to be used every retry on a link loss.
+	 * This flag is used to skip the fallback when link loss occurs during automation.
+	 */
+	bool skip_fallback_on_link_loss;
+
+	bool edp_sink_present;
+
+	struct dp_trace dp_trace;
+
+	/* caps is the same as reported_link_cap. link_traing use
+	 * reported_link_cap. Will clean up.  TODO
+	 */
+	struct dc_link_settings reported_link_cap;
+	struct dc_link_settings verified_link_cap;
+	struct dc_link_settings cur_link_settings;
+	struct dc_lane_settings cur_lane_setting[LANE_COUNT_DP_MAX];
+	struct dc_link_settings preferred_link_setting;
+	/* preferred_training_settings are override values that
+	 * come from DM. DM is responsible for the memory
+	 * management of the override pointers.
+	 */
+	struct dc_link_training_overrides preferred_training_settings;
+	struct dp_audio_test_data audio_test_data;
+
+	uint8_t ddc_hw_inst;
+
+	uint8_t hpd_src;
+
+	uint8_t link_enc_hw_inst;
+	/* DIG link encoder ID. Used as index in link encoder resource pool.
+	 * For links with fixed mapping to DIG, this is not changed after dc_link
+	 * object creation.
+	 */
+	enum engine_id eng_id;
+	enum engine_id dpia_preferred_eng_id;
+
+	bool test_pattern_enabled;
+	/* Pending/Current test pattern are only used to perform and track
+	 * FIXED_VS retimer test pattern/lane adjustment override state.
+	 * Pending allows link HWSS to differentiate PHY vs non-PHY pattern,
+	 * to perform specific lane adjust overrides before setting certain
+	 * PHY test patterns. In cases when lane adjust and set test pattern
+	 * calls are not performed atomically (i.e. performing link training),
+	 * pending_test_pattern will be invalid or contain a non-PHY test pattern
+	 * and current_test_pattern will contain required context for any future
+	 * set pattern/set lane adjust to transition between override state(s).
+	 * */
+	enum dp_test_pattern current_test_pattern;
+	enum dp_test_pattern pending_test_pattern;
+
+	union compliance_test_state compliance_test_state;
+
+	void *priv;
+
+	struct ddc_service *ddc;
+
+	enum dp_panel_mode panel_mode;
+	bool aux_mode;
+
+	/* Private to DC core */
+
+	const struct dc *dc;
+
+	struct dc_context *ctx;
+
+	struct panel_cntl *panel_cntl;
+	struct link_encoder *link_enc;
+	struct graphics_object_id link_id;
+	/* Endpoint type distinguishes display endpoints which do not have entries
+	 * in the BIOS connector table from those that do. Helps when tracking link
+	 * encoder to display endpoint assignments.
+	 */
+	enum display_endpoint_type ep_type;
+	union ddi_channel_mapping ddi_channel_mapping;
+	struct connector_device_tag_info device_tag;
+	struct dpcd_caps dpcd_caps;
+	uint32_t dongle_max_pix_clk;
+	unsigned short chip_caps;
+	unsigned int dpcd_sink_count;
+	struct hdcp_caps hdcp_caps;
+	enum edp_revision edp_revision;
+	union dpcd_sink_ext_caps dpcd_sink_ext_caps;
+
+	struct psr_settings psr_settings;
+	struct replay_settings replay_settings;
+
+	/* Drive settings read from integrated info table */
+	struct dc_lane_settings bios_forced_drive_settings;
+
+	/* Vendor specific LTTPR workaround variables */
+	uint8_t vendor_specific_lttpr_link_rate_wa;
+	bool apply_vendor_specific_lttpr_link_rate_wa;
+
+	/* MST record stream using this link */
+	struct link_flags {
+		bool dp_keep_receiver_powered;
+		bool dp_skip_DID2;
+		bool dp_skip_reset_segment;
+		bool dp_skip_fs_144hz;
+		bool dp_mot_reset_segment;
+		/* Some USB4 docks do not handle turning off MST DSC once it has been enabled. */
+		bool dpia_mst_dsc_always_on;
+		/* Forced DPIA into TBT3 compatibility mode. */
+		bool dpia_forced_tbt3_mode;
+		bool dongle_mode_timing_override;
+		bool blank_stream_on_ocs_change;
+		bool read_dpcd204h_on_irq_hpd;
+		bool force_dp_ffe_preset;
+	} wa_flags;
+	union dc_dp_ffe_preset forced_dp_ffe_preset;
+	struct link_mst_stream_allocation_table mst_stream_alloc_table;
+
+	struct dc_link_status link_status;
+	struct dprx_states dprx_states;
+
+	struct gpio *hpd_gpio;
+	enum dc_link_fec_state fec_state;
+	bool link_powered_externally;	// Used to bypass hardware sequencing delays when panel is powered down forcibly
+
+	struct dc_panel_config panel_config;
+	struct phy_state phy_state;
+	uint32_t phy_transition_bitmask;
+	// BW ALLOCATON USB4 ONLY
+	struct dc_dpia_bw_alloc dpia_bw_alloc_config;
+	bool skip_implict_edp_power_control;
+	enum backlight_control_type backlight_control_type;
+};
+
 struct dc {
 	struct dc_debug_options debug;
 	struct dc_versions versions;
@@ -1486,6 +1650,7 @@ struct dc {
 		struct dc_scratch_space current_state;
 		struct dc_scratch_space new_state;
 		struct dc_stream_state temp_stream; // Used so we don't need to allocate stream on the stack
+		struct dc_link temp_link;
 		bool pipes_to_unlock_first[MAX_PIPES]; /* Any of the pipes indicated here should be unlocked first */
 	} scratch;
 
@@ -1652,170 +1817,6 @@ uint32_t dc_bandwidth_in_kbps_from_timing(
 		const enum dc_link_encoding_format link_encoding);
 
 /* Link Interfaces */
-/*
- * A link contains one or more sinks and their connected status.
- * The currently active signal type (HDMI, DP-SST, DP-MST) is also reported.
- */
-struct dc_link {
-	struct dc_sink *remote_sinks[MAX_SINKS_PER_LINK];
-	unsigned int sink_count;
-	struct dc_sink *local_sink;
-	unsigned int link_index;
-	enum dc_connection_type type;
-	enum signal_type connector_signal;
-	enum dc_irq_source irq_source_hpd;
-	enum dc_irq_source irq_source_hpd_rx;/* aka DP Short Pulse  */
-
-	bool is_hpd_filter_disabled;
-	bool dp_ss_off;
-
-	/**
-	 * @link_state_valid:
-	 *
-	 * If there is no link and local sink, this variable should be set to
-	 * false. Otherwise, it should be set to true; usually, the function
-	 * core_link_enable_stream sets this field to true.
-	 */
-	bool link_state_valid;
-	bool aux_access_disabled;
-	bool sync_lt_in_progress;
-	bool skip_stream_reenable;
-	bool is_internal_display;
-	/** @todo Rename. Flag an endpoint as having a programmable mapping to a DIG encoder. */
-	bool is_dig_mapping_flexible;
-	bool hpd_status; /* HPD status of link without physical HPD pin. */
-	bool is_hpd_pending; /* Indicates a new received hpd */
-
-	/* USB4 DPIA links skip verifying link cap, instead performing the fallback method
-	 * for every link training. This is incompatible with DP LL compliance automation,
-	 * which expects the same link settings to be used every retry on a link loss.
-	 * This flag is used to skip the fallback when link loss occurs during automation.
-	 */
-	bool skip_fallback_on_link_loss;
-
-	bool edp_sink_present;
-
-	struct dp_trace dp_trace;
-
-	/* caps is the same as reported_link_cap. link_traing use
-	 * reported_link_cap. Will clean up.  TODO
-	 */
-	struct dc_link_settings reported_link_cap;
-	struct dc_link_settings verified_link_cap;
-	struct dc_link_settings cur_link_settings;
-	struct dc_lane_settings cur_lane_setting[LANE_COUNT_DP_MAX];
-	struct dc_link_settings preferred_link_setting;
-	/* preferred_training_settings are override values that
-	 * come from DM. DM is responsible for the memory
-	 * management of the override pointers.
-	 */
-	struct dc_link_training_overrides preferred_training_settings;
-	struct dp_audio_test_data audio_test_data;
-
-	uint8_t ddc_hw_inst;
-
-	uint8_t hpd_src;
-
-	uint8_t link_enc_hw_inst;
-	/* DIG link encoder ID. Used as index in link encoder resource pool.
-	 * For links with fixed mapping to DIG, this is not changed after dc_link
-	 * object creation.
-	 */
-	enum engine_id eng_id;
-	enum engine_id dpia_preferred_eng_id;
-
-	bool test_pattern_enabled;
-	/* Pending/Current test pattern are only used to perform and track
-	 * FIXED_VS retimer test pattern/lane adjustment override state.
-	 * Pending allows link HWSS to differentiate PHY vs non-PHY pattern,
-	 * to perform specific lane adjust overrides before setting certain
-	 * PHY test patterns. In cases when lane adjust and set test pattern
-	 * calls are not performed atomically (i.e. performing link training),
-	 * pending_test_pattern will be invalid or contain a non-PHY test pattern
-	 * and current_test_pattern will contain required context for any future
-	 * set pattern/set lane adjust to transition between override state(s).
-	 * */
-	enum dp_test_pattern current_test_pattern;
-	enum dp_test_pattern pending_test_pattern;
-
-	union compliance_test_state compliance_test_state;
-
-	void *priv;
-
-	struct ddc_service *ddc;
-
-	enum dp_panel_mode panel_mode;
-	bool aux_mode;
-
-	/* Private to DC core */
-
-	const struct dc *dc;
-
-	struct dc_context *ctx;
-
-	struct panel_cntl *panel_cntl;
-	struct link_encoder *link_enc;
-	struct graphics_object_id link_id;
-	/* Endpoint type distinguishes display endpoints which do not have entries
-	 * in the BIOS connector table from those that do. Helps when tracking link
-	 * encoder to display endpoint assignments.
-	 */
-	enum display_endpoint_type ep_type;
-	union ddi_channel_mapping ddi_channel_mapping;
-	struct connector_device_tag_info device_tag;
-	struct dpcd_caps dpcd_caps;
-	uint32_t dongle_max_pix_clk;
-	unsigned short chip_caps;
-	unsigned int dpcd_sink_count;
-	struct hdcp_caps hdcp_caps;
-	enum edp_revision edp_revision;
-	union dpcd_sink_ext_caps dpcd_sink_ext_caps;
-
-	struct psr_settings psr_settings;
-	struct replay_settings replay_settings;
-
-	/* Drive settings read from integrated info table */
-	struct dc_lane_settings bios_forced_drive_settings;
-
-	/* Vendor specific LTTPR workaround variables */
-	uint8_t vendor_specific_lttpr_link_rate_wa;
-	bool apply_vendor_specific_lttpr_link_rate_wa;
-
-	/* MST record stream using this link */
-	struct link_flags {
-		bool dp_keep_receiver_powered;
-		bool dp_skip_DID2;
-		bool dp_skip_reset_segment;
-		bool dp_skip_fs_144hz;
-		bool dp_mot_reset_segment;
-		/* Some USB4 docks do not handle turning off MST DSC once it has been enabled. */
-		bool dpia_mst_dsc_always_on;
-		/* Forced DPIA into TBT3 compatibility mode. */
-		bool dpia_forced_tbt3_mode;
-		bool dongle_mode_timing_override;
-		bool blank_stream_on_ocs_change;
-		bool read_dpcd204h_on_irq_hpd;
-		bool force_dp_ffe_preset;
-	} wa_flags;
-	union dc_dp_ffe_preset forced_dp_ffe_preset;
-	struct link_mst_stream_allocation_table mst_stream_alloc_table;
-
-	struct dc_link_status link_status;
-	struct dprx_states dprx_states;
-
-	struct gpio *hpd_gpio;
-	enum dc_link_fec_state fec_state;
-	bool link_powered_externally;	// Used to bypass hardware sequencing delays when panel is powered down forcibly
-
-	struct dc_panel_config panel_config;
-	struct phy_state phy_state;
-	uint32_t phy_transition_bitmask;
-	// BW ALLOCATON USB4 ONLY
-	struct dc_dpia_bw_alloc dpia_bw_alloc_config;
-	bool skip_implict_edp_power_control;
-	enum backlight_control_type backlight_control_type;
-};
-
 /* Return an enumerated dc_link.
  * dc_link order is constant and determined at
  * boot time.  They cannot be created or destroyed.
diff --git a/drivers/gpu/drm/amd/display/dc/inc/core_types.h b/drivers/gpu/drm/amd/display/dc/inc/core_types.h
index d0021f25f3d8..c1c8742d4a58 100644
--- a/drivers/gpu/drm/amd/display/dc/inc/core_types.h
+++ b/drivers/gpu/drm/amd/display/dc/inc/core_types.h
@@ -507,7 +507,7 @@ struct resource_context {
 	unsigned int hpo_dp_link_enc_to_link_idx[MAX_HPO_DP2_LINK_ENCODERS];
 	int hpo_dp_link_enc_ref_cnts[MAX_HPO_DP2_LINK_ENCODERS];
 	bool is_mpc_3dlut_acquired[MAX_PIPES];
-	/* solely used for build scalar data in dml2 */
+	/* used to build scalar data in dml2 and for edp backlight programming */
 	struct pipe_ctx temp_pipe;
 };
 
diff --git a/drivers/gpu/drm/amd/display/dc/link/protocols/link_edp_panel_control.c b/drivers/gpu/drm/amd/display/dc/link/protocols/link_edp_panel_control.c
index 1e4adbc764ea..669ac1bc662c 100644
--- a/drivers/gpu/drm/amd/display/dc/link/protocols/link_edp_panel_control.c
+++ b/drivers/gpu/drm/amd/display/dc/link/protocols/link_edp_panel_control.c
@@ -524,7 +524,7 @@ bool edp_set_backlight_level(const struct dc_link *link,
 	struct dc  *dc = link->ctx->dc;
 	uint32_t backlight_pwm_u16_16 = backlight_level_params->backlight_pwm_u16_16;
 	uint32_t frame_ramp = backlight_level_params->frame_ramp;
-	DC_LOGGER_INIT(link->ctx->logger);
+
 	DC_LOG_BACKLIGHT("New Backlight level: %d (0x%X)\n",
 			backlight_pwm_u16_16, backlight_pwm_u16_16);
 
@@ -1130,11 +1130,11 @@ static struct abm *get_abm_from_stream_res(const struct dc_link *link)
 	struct abm *abm = NULL;
 
 	for (i = 0; i < MAX_PIPES; i++) {
-		struct pipe_ctx pipe_ctx = dc->current_state->res_ctx.pipe_ctx[i];
-		struct dc_stream_state *stream = pipe_ctx.stream;
+		struct pipe_ctx *pipe_ctx = &dc->current_state->res_ctx.pipe_ctx[i];
+		struct dc_stream_state *stream = pipe_ctx->stream;
 
 		if (stream && stream->link == link) {
-			abm = pipe_ctx.stream_res.abm;
+			abm = pipe_ctx->stream_res.abm;
 			break;
 		}
 	}
-- 
2.49.0



More information about the amd-gfx mailing list