From: Michael Strauss <michael.stra...@amd.com>

[WHY]
New sequence for transparent mode DP1.x link training was provided by LTTPR
vendor

[HOW]
Implement new FIXED_VS sequence, increase LT retry count to minimize
any potential intermittent lightup failures

Reviewed-by: Jun Lei <jun....@amd.com>
Acked-by: Qingqing Zhuo <qingqing.z...@amd.com>
Signed-off-by: Michael Strauss <michael.stra...@amd.com>
---
 drivers/gpu/drm/amd/display/dc/dc.h           |   1 +
 .../drm/amd/display/dc/dcn31/dcn31_resource.c |   2 +
 .../gpu/drm/amd/display/dc/link/link_dpms.c   |   8 +-
 .../dc/link/protocols/link_dp_training.c      |   5 +-
 .../link_dp_training_fixed_vs_pe_retimer.c    | 378 +++++++++++++++++-
 .../link_dp_training_fixed_vs_pe_retimer.h    |   5 +
 6 files changed, 396 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/amd/display/dc/dc.h 
b/drivers/gpu/drm/amd/display/dc/dc.h
index f51b9c265b51..190e6a2e1334 100644
--- a/drivers/gpu/drm/amd/display/dc/dc.h
+++ b/drivers/gpu/drm/amd/display/dc/dc.h
@@ -405,6 +405,7 @@ struct dc_config {
        bool force_bios_enable_lttpr;
        uint8_t force_bios_fixed_vs;
        int sdpif_request_limit_words_per_umc;
+       bool use_old_fixed_vs_sequence;
        bool disable_subvp_drr;
 };
 
diff --git a/drivers/gpu/drm/amd/display/dc/dcn31/dcn31_resource.c 
b/drivers/gpu/drm/amd/display/dc/dcn31/dcn31_resource.c
index eaaa2e01f6d0..ff8cd5076434 100644
--- a/drivers/gpu/drm/amd/display/dc/dcn31/dcn31_resource.c
+++ b/drivers/gpu/drm/amd/display/dc/dcn31/dcn31_resource.c
@@ -1965,6 +1965,8 @@ static bool dcn31_resource_construct(
        dc->caps.color.mpc.ogam_rom_caps.hlg = 0;
        dc->caps.color.mpc.ocsc = 1;
 
+       dc->config.use_old_fixed_vs_sequence = true;
+
        /* Use pipe context based otg sync logic */
        dc->config.use_pipe_ctx_sync_logic = true;
 
diff --git a/drivers/gpu/drm/amd/display/dc/link/link_dpms.c 
b/drivers/gpu/drm/amd/display/dc/link/link_dpms.c
index f6c5ee2d639b..027ad1f0144d 100644
--- a/drivers/gpu/drm/amd/display/dc/link/link_dpms.c
+++ b/drivers/gpu/drm/amd/display/dc/link/link_dpms.c
@@ -2035,6 +2035,12 @@ static enum dc_status enable_link_dp(struct dc_state 
*state,
        uint32_t post_oui_delay = 30; // 30ms
        /* Reduce link bandwidth between failed link training attempts. */
        bool do_fallback = false;
+       int lt_attempts = LINK_TRAINING_ATTEMPTS;
+
+       // Increase retry count if attempting DP1.x on FIXED_VS link
+       if ((link->chip_caps & EXT_DISPLAY_PATH_CAPS__DP_FIXED_VS_EN) &&
+                       link_dp_get_encoding_format(link_settings) == 
DP_8b_10b_ENCODING)
+               lt_attempts = 10;
 
        // check for seamless boot
        for (i = 0; i < state->stream_count; i++) {
@@ -2099,7 +2105,7 @@ static enum dc_status enable_link_dp(struct dc_state 
*state,
 
        if (perform_link_training_with_retries(link_settings,
                                               skip_video_pattern,
-                                              LINK_TRAINING_ATTEMPTS,
+                                              lt_attempts,
                                               pipe_ctx,
                                               pipe_ctx->stream->signal,
                                               do_fallback)) {
diff --git a/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_training.c 
b/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_training.c
index f301c9eaf2f9..70fc0ddf2d7e 100644
--- a/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_training.c
+++ b/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_training.c
@@ -1496,7 +1496,10 @@ enum link_training_result dp_perform_link_training(
         * Non-LT AUX transactions inside training mode.
         */
        if ((link->chip_caps & EXT_DISPLAY_PATH_CAPS__DP_FIXED_VS_EN) && 
encoding == DP_8b_10b_ENCODING)
-               status = dp_perform_fixed_vs_pe_training_sequence(link, 
link_res, &lt_settings);
+               if (link->dc->config.use_old_fixed_vs_sequence)
+                       status = 
dp_perform_fixed_vs_pe_training_sequence_legacy(link, link_res, &lt_settings);
+               else
+                       status = dp_perform_fixed_vs_pe_training_sequence(link, 
link_res, &lt_settings);
        else if (encoding == DP_8b_10b_ENCODING)
                status = dp_perform_8b_10b_link_training(link, link_res, 
&lt_settings);
        else if (encoding == DP_128b_132b_ENCODING)
diff --git 
a/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_training_fixed_vs_pe_retimer.c
 
b/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_training_fixed_vs_pe_retimer.c
index a4071d2959a0..5731c4b61f9f 100644
--- 
a/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_training_fixed_vs_pe_retimer.c
+++ 
b/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_training_fixed_vs_pe_retimer.c
@@ -223,7 +223,7 @@ static enum link_training_result 
perform_fixed_vs_pe_nontransparent_training_seq
 }
 
 
-enum link_training_result dp_perform_fixed_vs_pe_training_sequence(
+enum link_training_result dp_perform_fixed_vs_pe_training_sequence_legacy(
        struct dc_link *link,
        const struct link_resource *link_res,
        struct link_training_settings *lt_settings)
@@ -577,3 +577,379 @@ enum link_training_result 
dp_perform_fixed_vs_pe_training_sequence(
 
        return status;
 }
+
+enum link_training_result dp_perform_fixed_vs_pe_training_sequence(
+       struct dc_link *link,
+       const struct link_resource *link_res,
+       struct link_training_settings *lt_settings)
+{
+       const uint8_t vendor_lttpr_write_data_reset[4] = {0x1, 0x50, 0x63, 
0xFF};
+       const uint8_t offset = dp_parse_lttpr_repeater_count(
+                       link->dpcd_caps.lttpr_caps.phy_repeater_cnt);
+       const uint8_t vendor_lttpr_write_data_intercept_en[4] = {0x1, 0x55, 
0x63, 0x0};
+       const uint8_t vendor_lttpr_write_data_intercept_dis[4] = {0x1, 0x55, 
0x63, 0x6E};
+       const uint8_t vendor_lttpr_write_data_adicora_eq1[4] = {0x1, 0x55, 
0x63, 0x2E};
+       const uint8_t vendor_lttpr_write_data_adicora_eq2[4] = {0x1, 0x55, 
0x63, 0x01};
+       const uint8_t vendor_lttpr_write_data_adicora_eq3[4] = {0x1, 0x55, 
0x63, 0x68};
+       uint32_t pre_disable_intercept_delay_ms = 
link->dc->debug.fixed_vs_aux_delay_config_wa;
+       uint8_t vendor_lttpr_write_data_vs[4] = {0x1, 0x51, 0x63, 0x0};
+       uint8_t vendor_lttpr_write_data_pe[4] = {0x1, 0x52, 0x63, 0x0};
+
+       uint32_t vendor_lttpr_write_address = 0xF004F;
+       enum link_training_result status = LINK_TRAINING_SUCCESS;
+       uint8_t lane = 0;
+       union down_spread_ctrl downspread = {0};
+       union lane_count_set lane_count_set = {0};
+       uint8_t toggle_rate;
+       uint8_t rate;
+
+       /* Only 8b/10b is supported */
+       ASSERT(link_dp_get_encoding_format(&lt_settings->link_settings) ==
+                       DP_8b_10b_ENCODING);
+
+       if (lt_settings->lttpr_mode == LTTPR_MODE_NON_TRANSPARENT) {
+               status = 
perform_fixed_vs_pe_nontransparent_training_sequence(link, link_res, 
lt_settings);
+               return status;
+       }
+
+       if (offset != 0xFF) {
+               vendor_lttpr_write_address +=
+                               ((DP_REPEATER_CONFIGURATION_AND_STATUS_SIZE) * 
(offset - 1));
+
+               /* Certain display and cable configuration require extra delay 
*/
+               if (offset > 2)
+                       pre_disable_intercept_delay_ms = 
link->dc->debug.fixed_vs_aux_delay_config_wa * 2;
+       }
+
+       /* Vendor specific: Reset lane settings */
+       core_link_write_dpcd(
+                       link,
+                       vendor_lttpr_write_address,
+                       &vendor_lttpr_write_data_reset[0],
+                       sizeof(vendor_lttpr_write_data_reset));
+       core_link_write_dpcd(
+                       link,
+                       vendor_lttpr_write_address,
+                       &vendor_lttpr_write_data_vs[0],
+                       sizeof(vendor_lttpr_write_data_vs));
+       core_link_write_dpcd(
+                       link,
+                       vendor_lttpr_write_address,
+                       &vendor_lttpr_write_data_pe[0],
+                       sizeof(vendor_lttpr_write_data_pe));
+
+       /* Vendor specific: Enable intercept */
+       core_link_write_dpcd(
+                       link,
+                       vendor_lttpr_write_address,
+                       &vendor_lttpr_write_data_intercept_en[0],
+                       sizeof(vendor_lttpr_write_data_intercept_en));
+
+       /* 1. set link rate, lane count and spread. */
+
+       downspread.raw = (uint8_t)(lt_settings->link_settings.link_spread);
+
+       lane_count_set.bits.LANE_COUNT_SET =
+       lt_settings->link_settings.lane_count;
+
+       lane_count_set.bits.ENHANCED_FRAMING = lt_settings->enhanced_framing;
+       lane_count_set.bits.POST_LT_ADJ_REQ_GRANTED = 0;
+
+
+       if (lt_settings->pattern_for_eq < DP_TRAINING_PATTERN_SEQUENCE_4) {
+               lane_count_set.bits.POST_LT_ADJ_REQ_GRANTED =
+                               
link->dpcd_caps.max_ln_count.bits.POST_LT_ADJ_REQ_SUPPORTED;
+       }
+
+       core_link_write_dpcd(link, DP_DOWNSPREAD_CTRL,
+               &downspread.raw, sizeof(downspread));
+
+       core_link_write_dpcd(link, DP_LANE_COUNT_SET,
+               &lane_count_set.raw, 1);
+
+       rate = get_dpcd_link_rate(&lt_settings->link_settings);
+
+       /* Vendor specific: Toggle link rate */
+       toggle_rate = (rate == 0x6) ? 0xA : 0x6;
+
+       if (link->vendor_specific_lttpr_link_rate_wa == rate) {
+               core_link_write_dpcd(
+                               link,
+                               DP_LINK_BW_SET,
+                               &toggle_rate,
+                               1);
+       }
+
+       link->vendor_specific_lttpr_link_rate_wa = rate;
+
+       core_link_write_dpcd(link, DP_LINK_BW_SET, &rate, 1);
+
+       DC_LOG_HW_LINK_TRAINING("%s\n %x rate = %x\n %x lane = %x framing = 
%x\n %x spread = %x\n",
+               __func__,
+               DP_LINK_BW_SET,
+               lt_settings->link_settings.link_rate,
+               DP_LANE_COUNT_SET,
+               lt_settings->link_settings.lane_count,
+               lt_settings->enhanced_framing,
+               DP_DOWNSPREAD_CTRL,
+               lt_settings->link_settings.link_spread);
+
+       /* 2. Perform link training */
+
+       /* Perform Clock Recovery Sequence */
+       if (status == LINK_TRAINING_SUCCESS) {
+               const uint8_t max_vendor_dpcd_retries = 10;
+               uint32_t retries_cr;
+               uint32_t retry_count;
+               uint32_t wait_time_microsec;
+               enum dc_lane_count lane_count = 
lt_settings->link_settings.lane_count;
+               union lane_status dpcd_lane_status[LANE_COUNT_DP_MAX];
+               union lane_align_status_updated dpcd_lane_status_updated;
+               union lane_adjust dpcd_lane_adjust[LANE_COUNT_DP_MAX] = {0};
+               enum dc_status dpcd_status = DC_OK;
+               uint8_t i = 0;
+
+               retries_cr = 0;
+               retry_count = 0;
+
+               memset(&dpcd_lane_status, '\0', sizeof(dpcd_lane_status));
+               memset(&dpcd_lane_status_updated, '\0',
+               sizeof(dpcd_lane_status_updated));
+
+               while ((retries_cr < LINK_TRAINING_MAX_RETRY_COUNT) &&
+                       (retry_count < LINK_TRAINING_MAX_CR_RETRY)) {
+
+
+                       /* 1. call HWSS to set lane settings */
+                       dp_set_hw_lane_settings(
+                                       link,
+                                       link_res,
+                                       lt_settings,
+                                       0);
+
+                       /* 2. update DPCD of the receiver */
+                       if (!retry_count) {
+                               /* EPR #361076 - write as a 5-byte burst,
+                                * but only for the 1-st iteration.
+                                */
+                               dpcd_set_lt_pattern_and_lane_settings(
+                                               link,
+                                               lt_settings,
+                                               lt_settings->pattern_for_cr,
+                                               0);
+                               /* Vendor specific: Disable intercept */
+                               for (i = 0; i < max_vendor_dpcd_retries; i++) {
+                                       msleep(pre_disable_intercept_delay_ms);
+                                       dpcd_status = core_link_write_dpcd(
+                                                       link,
+                                                       
vendor_lttpr_write_address,
+                                                       
&vendor_lttpr_write_data_intercept_dis[0],
+                                                       
sizeof(vendor_lttpr_write_data_intercept_dis));
+
+                                       if (dpcd_status == DC_OK)
+                                               break;
+
+                                       core_link_write_dpcd(
+                                                       link,
+                                                       
vendor_lttpr_write_address,
+                                                       
&vendor_lttpr_write_data_intercept_en[0],
+                                                       
sizeof(vendor_lttpr_write_data_intercept_en));
+                               }
+                       } else {
+                               vendor_lttpr_write_data_vs[3] = 0;
+                               vendor_lttpr_write_data_pe[3] = 0;
+
+                               for (lane = 0; lane < lane_count; lane++) {
+                                       vendor_lttpr_write_data_vs[3] |=
+                                                       
lt_settings->dpcd_lane_settings[lane].bits.VOLTAGE_SWING_SET << (2 * lane);
+                                       vendor_lttpr_write_data_pe[3] |=
+                                                       
lt_settings->dpcd_lane_settings[lane].bits.PRE_EMPHASIS_SET << (2 * lane);
+                               }
+
+                               /* Vendor specific: Update VS and PE to DPRX 
requested value */
+                               core_link_write_dpcd(
+                                               link,
+                                               vendor_lttpr_write_address,
+                                               &vendor_lttpr_write_data_vs[0],
+                                               
sizeof(vendor_lttpr_write_data_vs));
+                               core_link_write_dpcd(
+                                               link,
+                                               vendor_lttpr_write_address,
+                                               &vendor_lttpr_write_data_pe[0],
+                                               
sizeof(vendor_lttpr_write_data_pe));
+
+                               dpcd_set_lane_settings(
+                                               link,
+                                               lt_settings,
+                                               0);
+                       }
+
+                       /* 3. wait receiver to lock-on*/
+                       wait_time_microsec = lt_settings->cr_pattern_time;
+
+                       dp_wait_for_training_aux_rd_interval(
+                                       link,
+                                       wait_time_microsec);
+
+                       /* 4. Read lane status and requested drive
+                        * settings as set by the sink
+                        */
+                       dp_get_lane_status_and_lane_adjust(
+                                       link,
+                                       lt_settings,
+                                       dpcd_lane_status,
+                                       &dpcd_lane_status_updated,
+                                       dpcd_lane_adjust,
+                                       0);
+
+                       /* 5. check CR done*/
+                       if (dp_is_cr_done(lane_count, dpcd_lane_status)) {
+                               status = LINK_TRAINING_SUCCESS;
+                               break;
+                       }
+
+                       /* 6. max VS reached*/
+                       if (dp_is_max_vs_reached(lt_settings))
+                               break;
+
+                       /* 7. same lane settings */
+                       /* Note: settings are the same for all lanes,
+                        * so comparing first lane is sufficient
+                        */
+                       if 
(lt_settings->dpcd_lane_settings[0].bits.VOLTAGE_SWING_SET ==
+                                       
dpcd_lane_adjust[0].bits.VOLTAGE_SWING_LANE)
+                               retries_cr++;
+                       else
+                               retries_cr = 0;
+
+                       /* 8. update VS/PE/PC2 in lt_settings*/
+                       dp_decide_lane_settings(lt_settings, dpcd_lane_adjust,
+                                       lt_settings->hw_lane_settings, 
lt_settings->dpcd_lane_settings);
+                       retry_count++;
+               }
+
+               if (retry_count >= LINK_TRAINING_MAX_CR_RETRY) {
+                       ASSERT(0);
+                       DC_LOG_ERROR("%s: Link Training Error, could not get CR 
after %d tries. Possibly voltage swing issue",
+                               __func__,
+                               LINK_TRAINING_MAX_CR_RETRY);
+
+               }
+
+               status = dp_get_cr_failure(lane_count, dpcd_lane_status);
+       }
+
+       /* Perform Channel EQ Sequence */
+       if (status == LINK_TRAINING_SUCCESS) {
+               enum dc_dp_training_pattern tr_pattern;
+               uint32_t retries_ch_eq;
+               uint32_t wait_time_microsec;
+               enum dc_lane_count lane_count = 
lt_settings->link_settings.lane_count;
+               union lane_align_status_updated dpcd_lane_status_updated = {0};
+               union lane_status dpcd_lane_status[LANE_COUNT_DP_MAX] = {0};
+               union lane_adjust dpcd_lane_adjust[LANE_COUNT_DP_MAX] = {0};
+
+               core_link_write_dpcd(
+                               link,
+                               vendor_lttpr_write_address,
+                               &vendor_lttpr_write_data_adicora_eq1[0],
+                               sizeof(vendor_lttpr_write_data_adicora_eq1));
+               core_link_write_dpcd(
+                               link,
+                               vendor_lttpr_write_address,
+                               &vendor_lttpr_write_data_adicora_eq2[0],
+                               sizeof(vendor_lttpr_write_data_adicora_eq2));
+
+               /* Note: also check that TPS4 is a supported feature*/
+               tr_pattern = lt_settings->pattern_for_eq;
+
+               dp_set_hw_training_pattern(link, link_res, tr_pattern, 0);
+
+               status = LINK_TRAINING_EQ_FAIL_EQ;
+
+               for (retries_ch_eq = 0; retries_ch_eq <= 
LINK_TRAINING_MAX_RETRY_COUNT;
+                       retries_ch_eq++) {
+
+                       dp_set_hw_lane_settings(link, link_res, lt_settings, 0);
+
+                       vendor_lttpr_write_data_vs[3] = 0;
+                       vendor_lttpr_write_data_pe[3] = 0;
+
+                       for (lane = 0; lane < lane_count; lane++) {
+                               vendor_lttpr_write_data_vs[3] |=
+                                               
lt_settings->dpcd_lane_settings[lane].bits.VOLTAGE_SWING_SET << (2 * lane);
+                               vendor_lttpr_write_data_pe[3] |=
+                                               
lt_settings->dpcd_lane_settings[lane].bits.PRE_EMPHASIS_SET << (2 * lane);
+                       }
+
+                       /* Vendor specific: Update VS and PE to DPRX requested 
value */
+                       core_link_write_dpcd(
+                                       link,
+                                       vendor_lttpr_write_address,
+                                       &vendor_lttpr_write_data_vs[0],
+                                       sizeof(vendor_lttpr_write_data_vs));
+                       core_link_write_dpcd(
+                                       link,
+                                       vendor_lttpr_write_address,
+                                       &vendor_lttpr_write_data_pe[0],
+                                       sizeof(vendor_lttpr_write_data_pe));
+
+                       /* 2. update DPCD*/
+                       if (!retries_ch_eq) {
+                               /* EPR #361076 - write as a 5-byte burst,
+                                * but only for the 1-st iteration
+                                */
+
+                               dpcd_set_lt_pattern_and_lane_settings(
+                                       link,
+                                       lt_settings,
+                                       tr_pattern, 0);
+
+                               core_link_write_dpcd(
+                                       link,
+                                       vendor_lttpr_write_address,
+                                       &vendor_lttpr_write_data_adicora_eq3[0],
+                                       
sizeof(vendor_lttpr_write_data_adicora_eq3));
+                       } else
+                               dpcd_set_lane_settings(link, lt_settings, 0);
+
+                       /* 3. wait for receiver to lock-on*/
+                       wait_time_microsec = lt_settings->eq_pattern_time;
+
+                       dp_wait_for_training_aux_rd_interval(
+                                       link,
+                                       wait_time_microsec);
+
+                       /* 4. Read lane status and requested
+                        * drive settings as set by the sink
+                        */
+                       dp_get_lane_status_and_lane_adjust(
+                               link,
+                               lt_settings,
+                               dpcd_lane_status,
+                               &dpcd_lane_status_updated,
+                               dpcd_lane_adjust,
+                               0);
+
+                       /* 5. check CR done*/
+                       if (!dp_is_cr_done(lane_count, dpcd_lane_status)) {
+                               status = LINK_TRAINING_EQ_FAIL_CR;
+                               break;
+                       }
+
+                       /* 6. check CHEQ done*/
+                       if (dp_is_ch_eq_done(lane_count, dpcd_lane_status) &&
+                                       dp_is_symbol_locked(lane_count, 
dpcd_lane_status) &&
+                                       
dp_is_interlane_aligned(dpcd_lane_status_updated)) {
+                               status = LINK_TRAINING_SUCCESS;
+                               break;
+                       }
+
+                       /* 7. update VS/PE/PC2 in lt_settings*/
+                       dp_decide_lane_settings(lt_settings, dpcd_lane_adjust,
+                                       lt_settings->hw_lane_settings, 
lt_settings->dpcd_lane_settings);
+               }
+       }
+
+       return status;
+}
diff --git 
a/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_training_fixed_vs_pe_retimer.h
 
b/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_training_fixed_vs_pe_retimer.h
index e61970e27661..c0d6ea329504 100644
--- 
a/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_training_fixed_vs_pe_retimer.h
+++ 
b/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_training_fixed_vs_pe_retimer.h
@@ -28,6 +28,11 @@
 #define __DC_LINK_DP_FIXED_VS_PE_RETIMER_H__
 #include "link_dp_training.h"
 
+enum link_training_result dp_perform_fixed_vs_pe_training_sequence_legacy(
+       struct dc_link *link,
+       const struct link_resource *link_res,
+       struct link_training_settings *lt_settings);
+
 enum link_training_result dp_perform_fixed_vs_pe_training_sequence(
        struct dc_link *link,
        const struct link_resource *link_res,
-- 
2.34.1

Reply via email to