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From e56d9800bac89178bca2adae9ce2f4775f561262 Mon Sep 17 00:00:00 2001
From: abdoulaye berthe <abdoulaye.berthe@amd.com>
Date: Fri, 19 Jul 2019 10:43:42 -0400
Subject: [PATCH 4397/4736] drm/amd/display: configure lttpr mode
[Description]
1-Grant extended timeout request. Done once after detection
2-Configure lttpr mode based on lttpr support before LT
3-Account for lttpr cap when determining max link settings
Signed-off-by: abdoulaye berthe <abdoulaye.berthe@amd.com>
Reviewed-by: Aric Cyr <Aric.Cyr@amd.com>
---
.../gpu/drm/amd/display/dc/core/dc_link_dp.c | 42 +++++++++++++++++++
1 file changed, 42 insertions(+)
diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c b/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c
index 1e4480f3bd3c..94d5a0ac308f 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c
@@ -1057,6 +1057,26 @@ static void initialize_training_settings(
lt_settings->enhanced_framing = 1;
}
+static void configure_lttpr_mode(struct dc_link *link)
+{
+ /* aux timeout is already set to extended */
+ /* RESET/SET lttpr mode to enable non transparent mode */
+ enum lttpr_mode repeater_mode = phy_repeater_mode_transparent;
+
+ core_link_write_dpcd(link,
+ DP_PHY_REPEATER_MODE,
+ (uint8_t *)&repeater_mode,
+ sizeof(repeater_mode));
+
+ if (!link->is_lttpr_mode_transparent) {
+ repeater_mode = phy_repeater_mode_non_transparent;
+ core_link_write_dpcd(link,
+ DP_PHY_REPEATER_MODE,
+ (uint8_t *)&repeater_mode,
+ sizeof(repeater_mode));
+ }
+}
+
static void print_status_message(
struct dc_link *link,
const struct link_training_settings *lt_settings,
@@ -1210,6 +1230,9 @@ enum link_training_result dc_link_dp_perform_link_training(
dp_set_fec_ready(link, fec_enable);
#endif
+ /* Configure lttpr mode */
+ if (!link->is_lttpr_mode_transparent)
+ configure_lttpr_mode(link);
/* 2. perform link training (set link training done
* to false is done as well)
@@ -1426,6 +1449,17 @@ static struct dc_link_settings get_max_link_cap(struct dc_link *link)
max_link_cap.link_spread)
max_link_cap.link_spread =
link->reported_link_cap.link_spread;
+ /*
+ * account for lttpr repeaters cap
+ * notes: repeaters do not snoop in the DPRX Capabilities addresses (3.6.3).
+ */
+ if (!link->is_lttpr_mode_transparent) {
+ 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;
+
+ if (link->dpcd_caps.lttpr_caps.max_link_rate < max_link_cap.link_rate)
+ max_link_cap.link_rate = link->dpcd_caps.lttpr_caps.max_link_rate;
+ }
return max_link_cap;
}
@@ -1571,6 +1605,13 @@ bool dp_verify_link_cap(
max_link_cap = get_max_link_cap(link);
+ /* Grant extended timeout request */
+ if (!link->is_lttpr_mode_transparent && link->dpcd_caps.lttpr_caps.max_ext_timeout > 0) {
+ uint8_t grant = link->dpcd_caps.lttpr_caps.max_ext_timeout & 0x80;
+
+ core_link_write_dpcd(link, DP_PHY_REPEATER_EXTENDED_WAIT_TIMEOUT, &grant, sizeof(grant));
+ }
+
/* TODO implement override and monitor patch later */
/* try to train the link from high to low to
@@ -2759,6 +2800,7 @@ static bool retrieve_link_cap(struct dc_link *link)
/* Set default timeout to 3.2ms and read LTTPR capabilities */
bool ext_timeout_support = link->dc->caps.extended_aux_timeout_support &&
!link->dc->config.disable_extended_timeout_support;
+
link->is_lttpr_mode_transparent = true;
if (ext_timeout_support) {
--
2.17.1
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