drm/amd/display: Revert "DP link layer test 4.2.1.1 fix due to specs update"

[why]
The change causes some regression in a common use case.
Will need more investigation before fixing the original issue.

[how]
This reverts commit fb8cf277b16d3f8b16941d217f7bae4ed7e73bea.

Signed-off-by: Wenjing Liu <wenjing.liu@amd.com>
Reviewed-by: Jun Lei <Jun.Lei@amd.com>
Acked-by: Qingqing Zhuo <qingqing.zhuo@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link.c b/drivers/gpu/drm/amd/display/dc/core/dc_link.c
index cb5491f..cbb4c24 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/core/dc_link.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_link.c
@@ -690,11 +690,9 @@ static bool detect_dp(struct dc_link *link,
 
        if (sink_caps->transaction_type == DDC_TRANSACTION_TYPE_I2C_OVER_AUX) {
                sink_caps->signal = SIGNAL_TYPE_DISPLAY_PORT;
-
+               dpcd_set_source_specific_data(link);
                if (!detect_dp_sink_caps(link))
                        return false;
-               dpcd_set_source_specific_data(link);
-
                if (is_mst_supported(link)) {
                        sink_caps->signal = SIGNAL_TYPE_DISPLAY_PORT_MST;
                        link->type = dc_connection_mst_branch;

diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link_ddc.c b/drivers/gpu/drm/amd/display/dc/core/dc_link_ddc.c
index 242ed59..aefd29a 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/core/dc_link_ddc.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_link_ddc.c
@@ -648,17 +648,16 @@ bool dc_link_aux_transfer_with_retries(struct ddc_service *ddc,
 }
 
 
-bool dc_link_aux_try_to_configure_timeout(struct ddc_service *ddc,
+uint32_t dc_link_aux_configure_timeout(struct ddc_service *ddc,
                uint32_t timeout)
 {
-       bool result = false;
+       uint32_t prev_timeout = 0;
        struct ddc *ddc_pin = ddc->ddc_pin;
 
-       if (ddc->ctx->dc->res_pool->engines[ddc_pin->pin_data->en]->funcs->configure_timeout) {
-               ddc->ctx->dc->res_pool->engines[ddc_pin->pin_data->en]->funcs->configure_timeout(ddc, timeout);
-               result = true;
-       }
-       return result;
+       if (ddc->ctx->dc->res_pool->engines[ddc_pin->pin_data->en]->funcs->configure_timeout)
+               prev_timeout =
+                               ddc->ctx->dc->res_pool->engines[ddc_pin->pin_data->en]->funcs->configure_timeout(ddc, timeout);
+       return prev_timeout;
 }
 
 /*test only function*/

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 97703f8..fe15bdb 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c
@@ -245,7 +245,7 @@ static uint8_t dc_dp_initialize_scrambling_data_symbols(
 
 static inline bool is_repeater(struct dc_link *link, uint32_t offset)
 {
-       return (link->lttpr_non_transparent_mode && offset != 0);
+       return (!link->is_lttpr_mode_transparent && offset != 0);
 }
 
 static void dpcd_set_lt_pattern_and_lane_settings(
@@ -1038,7 +1038,7 @@ static enum link_training_result perform_clock_recovery_sequence(
                /* 3. wait receiver to lock-on*/
                wait_time_microsec = lt_settings->cr_pattern_time;
 
-               if (link->lttpr_non_transparent_mode)
+               if (!link->is_lttpr_mode_transparent)
                        wait_time_microsec = TRAINING_AUX_RD_INTERVAL;
 
                wait_for_training_aux_rd_interval(
@@ -1268,7 +1268,7 @@ static void configure_lttpr_mode(struct dc_link *link)
                link->dpcd_caps.lttpr_caps.mode = repeater_mode;
        }
 
-       if (link->lttpr_non_transparent_mode) {
+       if (!link->is_lttpr_mode_transparent) {
 
                DC_LOG_HW_LINK_TRAINING("%s\n Set LTTPR to Non Transparent Mode\n", __func__);
 
@@ -1473,7 +1473,7 @@ enum link_training_result dc_link_dp_perform_link_training(
                        &lt_settings);
 
        /* Configure lttpr mode */
-       if (link->lttpr_non_transparent_mode)
+       if (!link->is_lttpr_mode_transparent)
                configure_lttpr_mode(link);
 
        if (link->ctx->dc->work_arounds.lt_early_cr_pattern)
@@ -1489,7 +1489,7 @@ enum link_training_result dc_link_dp_perform_link_training(
 
        dp_set_fec_ready(link, fec_enable);
 
-       if (link->lttpr_non_transparent_mode) {
+       if (!link->is_lttpr_mode_transparent) {
 
                /* 2. perform link training (set link training done
                 *  to false is done as well)
@@ -1757,7 +1757,7 @@ static struct dc_link_settings get_max_link_cap(struct dc_link *link)
         * account for lttpr repeaters cap
         * notes: repeaters do not snoop in the DPRX Capabilities addresses (3.6.3).
         */
-       if (link->lttpr_non_transparent_mode) {
+       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;
 
@@ -1915,7 +1915,7 @@ bool dp_verify_link_cap(
        max_link_cap = get_max_link_cap(link);
 
        /* Grant extended timeout request */
-       if (link->lttpr_non_transparent_mode && link->dpcd_caps.lttpr_caps.max_ext_timeout > 0) {
+       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));
@@ -3248,7 +3248,17 @@ static bool retrieve_link_cap(struct dc_link *link)
        uint32_t read_dpcd_retry_cnt = 3;
        int i;
        struct dp_sink_hw_fw_revision dp_hw_fw_revision;
-       bool is_lttpr_present = false;
+
+       /* 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) {
+               dc_link_aux_configure_timeout(link->ddc,
+                                       LINK_AUX_DEFAULT_EXTENDED_TIMEOUT_PERIOD);
+       }
 
        memset(dpcd_data, '\0', sizeof(dpcd_data));
        memset(lttpr_dpcd_data, '\0', sizeof(lttpr_dpcd_data));
@@ -3257,13 +3267,6 @@ static bool retrieve_link_cap(struct dc_link *link)
        memset(&edp_config_cap, '\0',
                sizeof(union edp_configuration_cap));
 
-       /* if extended timeout is supported in hardware,
-        * default to LTTPR timeout (3.2ms) first as a W/A for DP link layer
-        * CTS 4.2.1.1 regression introduced by CTS specs requirement update.
-        */
-       dc_link_aux_try_to_configure_timeout(link->ddc,
-                       LINK_AUX_DEFAULT_LTTPR_TIMEOUT_PERIOD);
-
        status = core_link_read_dpcd(link, DP_SET_POWER,
                                &dpcd_power_state, sizeof(dpcd_power_state));
 
@@ -3290,9 +3293,8 @@ static bool retrieve_link_cap(struct dc_link *link)
                return false;
        }
 
-       if (link->dc->caps.extended_aux_timeout_support) {
-               /* By reading LTTPR capability, RX assumes that we will enable LTTPR extended aux timeout if LTTPR is present.
-                * Therefore, only query LTTPR capability when LTTPR extended aux timeout is supported by hardware */
+       if (ext_timeout_support) {
+
                status = core_link_read_dpcd(
                                link,
                                DP_LT_TUNABLE_PHY_REPEATER_FIELD_DATA_STRUCTURE_REV,
@@ -3323,20 +3325,19 @@ static bool retrieve_link_cap(struct dc_link *link)
                                lttpr_dpcd_data[DP_PHY_REPEATER_EXTENDED_WAIT_TIMEOUT -
                                                                DP_LT_TUNABLE_PHY_REPEATER_FIELD_DATA_STRUCTURE_REV];
 
-               is_lttpr_present = (link->dpcd_caps.lttpr_caps.phy_repeater_cnt > 0 &&
+               if (link->dpcd_caps.lttpr_caps.phy_repeater_cnt > 0 &&
                                link->dpcd_caps.lttpr_caps.max_lane_count > 0 &&
                                link->dpcd_caps.lttpr_caps.max_lane_count <= 4 &&
-                               link->dpcd_caps.lttpr_caps.revision.raw >= 0x14);
-               if (is_lttpr_present)
-                       CONN_DATA_DETECT(link, lttpr_dpcd_data, sizeof(lttpr_dpcd_data), "LTTPR Caps: ");
-       }
-
-       /* decide lttpr non transparent mode */
-       link->lttpr_non_transparent_mode = is_lttpr_present && link->dc->config.allow_lttpr_non_transparent_mode;
-
-       if (!is_lttpr_present)
-               dc_link_aux_try_to_configure_timeout(link->ddc, LINK_AUX_DEFAULT_TIMEOUT_PERIOD);
+                               link->dpcd_caps.lttpr_caps.revision.raw >= 0x14) {
+                       link->is_lttpr_mode_transparent = false;
+               } else {
+                       /*No lttpr reset timeout to its default value*/
+                       link->is_lttpr_mode_transparent = true;
+                       dc_link_aux_configure_timeout(link->ddc, LINK_AUX_DEFAULT_TIMEOUT_PERIOD);
+               }
 
+               CONN_DATA_DETECT(link, lttpr_dpcd_data, sizeof(lttpr_dpcd_data), "LTTPR Caps: ");
+       }
 
        {
                union training_aux_rd_interval aux_rd_interval;

diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link_hwss.c b/drivers/gpu/drm/amd/display/dc/core/dc_link_hwss.c
index 6bbe4e7..6590f51 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/core/dc_link_hwss.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_link_hwss.c
@@ -281,7 +281,7 @@ void dp_set_hw_lane_settings(
 {
        struct link_encoder *encoder = link->link_enc;
 
-       if (link->lttpr_non_transparent_mode && !is_immediate_downstream(link, offset))
+       if (!link->is_lttpr_mode_transparent && !is_immediate_downstream(link, offset))
                return;
 
        /* call Encoder to set lane settings */

diff --git a/drivers/gpu/drm/amd/display/dc/dc.h b/drivers/gpu/drm/amd/display/dc/dc.h
index 9138adf..f9bdd91 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/dc.h
+++ b/drivers/gpu/drm/amd/display/dc/dc.h
@@ -283,7 +283,7 @@ struct dc_config {
        bool edp_not_connected;
        bool force_enum_edp;
        bool forced_clocks;
-       bool allow_lttpr_non_transparent_mode;
+       bool disable_extended_timeout_support; // Used to disable extended timeout and lttpr feature as well
        bool multi_mon_pp_mclk_switch;
        bool disable_dmcu;
        bool enable_4to1MPC;

diff --git a/drivers/gpu/drm/amd/display/dc/dc_link.h b/drivers/gpu/drm/amd/display/dc/dc_link.h
index aec514e..79aca1b 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/dc_link.h
+++ b/drivers/gpu/drm/amd/display/dc/dc_link.h
@@ -101,7 +101,6 @@ struct dc_link {
        bool aux_access_disabled;
        bool sync_lt_in_progress;
        bool is_lttpr_mode_transparent;
-       bool lttpr_non_transparent_mode;
 
        /* caps is the same as reported_link_cap. link_traing use
         * reported_link_cap. Will clean up.  TODO

diff --git a/drivers/gpu/drm/amd/display/dc/dcn21/dcn21_resource.c b/drivers/gpu/drm/amd/display/dc/dcn21/dcn21_resource.c
index 24aa3f1..7a37065 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/dcn21/dcn21_resource.c
+++ b/drivers/gpu/drm/amd/display/dc/dcn21/dcn21_resource.c
@@ -1806,7 +1806,7 @@ static bool dcn21_resource_construct(
        dc->caps.max_slave_planes = 1;
        dc->caps.post_blend_color_processing = true;
        dc->caps.force_dp_tps4_for_cp2520 = true;
-       dc->caps.extended_aux_timeout_support = true;
+       dc->caps.extended_aux_timeout_support = false;
        dc->caps.dmcub_support = true;
        dc->caps.is_apu = true;
 

diff --git a/drivers/gpu/drm/amd/display/dc/inc/dc_link_ddc.h b/drivers/gpu/drm/amd/display/dc/inc/dc_link_ddc.h
index b324e13..de2d160 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/inc/dc_link_ddc.h
+++ b/drivers/gpu/drm/amd/display/dc/inc/dc_link_ddc.h
@@ -105,7 +105,7 @@ int dc_link_aux_transfer_raw(struct ddc_service *ddc,
 bool dc_link_aux_transfer_with_retries(struct ddc_service *ddc,
                struct aux_payload *payload);
 
-bool dc_link_aux_try_to_configure_timeout(struct ddc_service *ddc,
+uint32_t dc_link_aux_configure_timeout(struct ddc_service *ddc,
                uint32_t timeout);
 
 void dal_ddc_service_write_scdc_data(

diff --git a/drivers/gpu/drm/amd/display/dc/inc/dc_link_dp.h b/drivers/gpu/drm/amd/display/dc/inc/dc_link_dp.h
index b970a32..e94e5fb 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/inc/dc_link_dp.h
+++ b/drivers/gpu/drm/amd/display/dc/inc/dc_link_dp.h
@@ -28,7 +28,7 @@
 
 #define LINK_TRAINING_ATTEMPTS 4
 #define LINK_TRAINING_RETRY_DELAY 50 /* ms */
-#define LINK_AUX_DEFAULT_LTTPR_TIMEOUT_PERIOD 3200 /*us*/
+#define LINK_AUX_DEFAULT_EXTENDED_TIMEOUT_PERIOD 3200 /*us*/
 #define LINK_AUX_DEFAULT_TIMEOUT_PERIOD 552 /*us*/
 
 struct dc_link;