Commit 13ab3a8f authored by Peichen Huang's avatar Peichen Huang Committed by Alex Deucher
Browse files

drm/amd/display: lttpr cap should be nrd cap in bw_alloc mode 



[WHY]
When bw allocation mode enabled, dpia may reports lttpr cap with
reduced common cap. It would cause driver not start pre-training with
max available bandwidth.

[How]
When bw allocation mode enabled, use NRD cap as lttpr cap.

Reviewed-by: default avatarCruise Hung <cruise.hung@amd.com>
Reviewed-by: default avatarWenjing Liu <wenjing.liu@amd.com>
Signed-off-by: default avatarPeichen Huang <PeiChen.Huang@amd.com>
Signed-off-by: default avatarRoman Li <roman.li@amd.com>
Tested-by: default avatarDan Wheeler <daniel.wheeler@amd.com>
Signed-off-by: default avatarAlex Deucher <alexander.deucher@amd.com>
parent 6d92c4d0

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

+36 −2
Original line number Diff line number Diff line
@@ -424,6 +424,21 @@ static enum dc_link_rate get_link_rate_from_max_link_bw( 
	return link_rate;

}



static enum dc_lane_count get_lttpr_max_lane_count(struct dc_link *link)

{

	enum dc_lane_count lttpr_max_lane_count = LANE_COUNT_UNKNOWN;



	if (link->dpcd_caps.lttpr_caps.max_lane_count <= LANE_COUNT_DP_MAX)

		lttpr_max_lane_count = link->dpcd_caps.lttpr_caps.max_lane_count;



	/* if bw_allocation is enabled and nrd_max_lane_count is set, use it */

	if (link->dpia_bw_alloc_config.bw_alloc_enabled &&

			link->dpia_bw_alloc_config.nrd_max_lane_count > 0)

		lttpr_max_lane_count = link->dpia_bw_alloc_config.nrd_max_lane_count;



	return lttpr_max_lane_count;

}



static enum dc_link_rate get_lttpr_max_link_rate(struct dc_link *link)

{
@@ -438,6 +453,11 @@ static enum dc_link_rate get_lttpr_max_link_rate(struct dc_link *link) 
		break;

	}



	/* if bw_allocation is enabled and nrd_max_link_rate is set, use it */

	if (link->dpia_bw_alloc_config.bw_alloc_enabled &&

			link->dpia_bw_alloc_config.nrd_max_link_rate > 0)

		lttpr_max_link_rate = link->dpia_bw_alloc_config.nrd_max_link_rate;



	if (link->dpcd_caps.lttpr_caps.supported_128b_132b_rates.bits.UHBR20)

		lttpr_max_link_rate = LINK_RATE_UHBR20;

	else if (link->dpcd_caps.lttpr_caps.supported_128b_132b_rates.bits.UHBR13_5)
@@ -2241,6 +2261,7 @@ const struct dc_link_settings *dp_get_verified_link_cap( 
struct dc_link_settings dp_get_max_link_cap(struct dc_link *link)

{

	struct dc_link_settings max_link_cap = {0};

	enum dc_lane_count lttpr_max_lane_count;

	enum dc_link_rate lttpr_max_link_rate;

	enum dc_link_rate cable_max_link_rate;

	struct resource_context *res_ctx = &link->dc->current_state->res_ctx;
@@ -2305,8 +2326,11 @@ struct dc_link_settings dp_get_max_link_cap(struct dc_link *link) 


		/* Some LTTPR devices do not report valid DPCD revisions, if so, do not take it's link cap into consideration. */

		if (link->dpcd_caps.lttpr_caps.revision.raw >= DPCD_REV_14) {

			if (link->dpcd_caps.lttpr_caps.max_lane_count < max_link_cap.lane_count)

				max_link_cap.lane_count = link->dpcd_caps.lttpr_caps.max_lane_count;

			lttpr_max_lane_count = get_lttpr_max_lane_count(link);



			if (lttpr_max_lane_count < max_link_cap.lane_count)

				max_link_cap.lane_count = lttpr_max_lane_count;



			lttpr_max_link_rate = get_lttpr_max_link_rate(link);



			if (lttpr_max_link_rate < max_link_cap.link_rate)
@@ -2412,6 +2436,11 @@ bool dp_verify_link_cap_with_retries( 


	dp_trace_detect_lt_init(link);



	DC_LOG_HW_LINK_TRAINING("%s: Link[%d]  LinkRate=0x%x LaneCount=%d",

		__func__, link->link_index,

		known_limit_link_setting->link_rate,

		known_limit_link_setting->lane_count);



	if (link->link_enc && link->link_enc->features.flags.bits.DP_IS_USB_C &&

			link->dc->debug.usbc_combo_phy_reset_wa)

		apply_usbc_combo_phy_reset_wa(link, known_limit_link_setting);
@@ -2448,6 +2477,11 @@ bool dp_verify_link_cap_with_retries( 
	dp_trace_lt_fail_count_update(link, fail_count, true);

	dp_trace_set_lt_end_timestamp(link, true);



	DC_LOG_HW_LINK_TRAINING("%s: Link[%d]  Exit. is_success=%d  fail_count=%d",

		__func__, link->link_index,

		success,

		fail_count);



	return success;

}