diff options
Diffstat (limited to 'drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_training_dpia.c')
| -rw-r--r-- | drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_training_dpia.c | 1044 |
1 files changed, 1044 insertions, 0 deletions
diff --git a/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_training_dpia.c b/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_training_dpia.c new file mode 100644 index 000000000000..05657627ae45 --- /dev/null +++ b/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_training_dpia.c @@ -0,0 +1,1044 @@ +/* + * Copyright 2022 Advanced Micro Devices, Inc. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR + * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, + * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR + * OTHER DEALINGS IN THE SOFTWARE. + * + * Authors: AMD + * + */ + +/* FILE POLICY AND INTENDED USAGE: + * This module implements functionality for training DPIA links. + */ +#include "link_dp_training_dpia.h" +#include "dc.h" +#include "inc/core_status.h" +#include "dc_link.h" +#include "dpcd_defs.h" + +#include "link_dp_dpia.h" +#include "link_hwss.h" +#include "dm_helpers.h" +#include "dmub/inc/dmub_cmd.h" +#include "link_dpcd.h" +#include "link_dp_training_8b_10b.h" +#include "link_dp_capability.h" +#include "dc_dmub_srv.h" +#define DC_LOGGER \ + link->ctx->logger + +/* The approximate time (us) it takes to transmit 9 USB4 DP clock sync packets. */ +#define DPIA_CLK_SYNC_DELAY 16000 + +/* Extend interval between training status checks for manual testing. */ +#define DPIA_DEBUG_EXTENDED_AUX_RD_INTERVAL_US 60000000 + +/* SET_CONFIG message types sent by driver. */ +enum dpia_set_config_type { + DPIA_SET_CFG_SET_LINK = 0x01, + DPIA_SET_CFG_SET_PHY_TEST_MODE = 0x05, + DPIA_SET_CFG_SET_TRAINING = 0x18, + DPIA_SET_CFG_SET_VSPE = 0x19 +}; + +/* Training stages (TS) in SET_CONFIG(SET_TRAINING) message. */ +enum dpia_set_config_ts { + DPIA_TS_DPRX_DONE = 0x00, /* Done training DPRX. */ + DPIA_TS_TPS1 = 0x01, + DPIA_TS_TPS2 = 0x02, + DPIA_TS_TPS3 = 0x03, + DPIA_TS_TPS4 = 0x07, + DPIA_TS_UFP_DONE = 0xff /* Done training DPTX-to-DPIA hop. */ +}; + +/* SET_CONFIG message data associated with messages sent by driver. */ +union dpia_set_config_data { + struct { + uint8_t mode : 1; + uint8_t reserved : 7; + } set_link; + struct { + uint8_t stage; + } set_training; + struct { + uint8_t swing : 2; + uint8_t max_swing_reached : 1; + uint8_t pre_emph : 2; + uint8_t max_pre_emph_reached : 1; + uint8_t reserved : 2; + } set_vspe; + uint8_t raw; +}; + + +/* Configure link as prescribed in link_setting; set LTTPR mode; and + * Initialize link training settings. + * Abort link training if sink unplug detected. + * + * @param link DPIA link being trained. + * @param[in] link_setting Lane count, link rate and downspread control. + * @param[out] lt_settings Link settings and drive settings (voltage swing and pre-emphasis). + */ +static enum link_training_result dpia_configure_link( + struct dc_link *link, + const struct link_resource *link_res, + const struct dc_link_settings *link_setting, + struct link_training_settings *lt_settings) +{ + enum dc_status status; + bool fec_enable; + + DC_LOG_HW_LINK_TRAINING("%s\n DPIA(%d) configuring\n - LTTPR mode(%d)\n", + __func__, + link->link_id.enum_id - ENUM_ID_1, + lt_settings->lttpr_mode); + + dp_decide_training_settings( + link, + link_setting, + lt_settings); + + dp_get_lttpr_mode_override(link, <_settings->lttpr_mode); + + status = dpcd_configure_channel_coding(link, lt_settings); + if (status != DC_OK && link->is_hpd_pending) + return LINK_TRAINING_ABORT; + + /* Configure lttpr mode */ + status = dpcd_configure_lttpr_mode(link, lt_settings); + if (status != DC_OK && link->is_hpd_pending) + return LINK_TRAINING_ABORT; + + /* Set link rate, lane count and spread. */ + status = dpcd_set_link_settings(link, lt_settings); + if (status != DC_OK && link->is_hpd_pending) + return LINK_TRAINING_ABORT; + + if (link->preferred_training_settings.fec_enable != NULL) + fec_enable = *link->preferred_training_settings.fec_enable; + else + fec_enable = true; + status = dp_set_fec_ready(link, link_res, fec_enable); + if (status != DC_OK && link->is_hpd_pending) + return LINK_TRAINING_ABORT; + + return LINK_TRAINING_SUCCESS; +} + +static enum dc_status core_link_send_set_config( + struct dc_link *link, + uint8_t msg_type, + uint8_t msg_data) +{ + struct set_config_cmd_payload payload; + enum set_config_status set_config_result = SET_CONFIG_PENDING; + + /* prepare set_config payload */ + payload.msg_type = msg_type; + payload.msg_data = msg_data; + + if (!link->ddc->ddc_pin && !link->aux_access_disabled && + (dm_helpers_dmub_set_config_sync(link->ctx, + link, &payload, &set_config_result) == -1)) { + return DC_ERROR_UNEXPECTED; + } + + /* set_config should return ACK if successful */ + return (set_config_result == SET_CONFIG_ACK_RECEIVED) ? DC_OK : DC_ERROR_UNEXPECTED; +} + +/* Build SET_CONFIG message data payload for specified message type. */ +static uint8_t dpia_build_set_config_data( + enum dpia_set_config_type type, + struct dc_link *link, + struct link_training_settings *lt_settings) +{ + union dpia_set_config_data data; + + data.raw = 0; + + switch (type) { + case DPIA_SET_CFG_SET_LINK: + data.set_link.mode = lt_settings->lttpr_mode == LTTPR_MODE_NON_TRANSPARENT ? 1 : 0; + break; + case DPIA_SET_CFG_SET_PHY_TEST_MODE: + break; + case DPIA_SET_CFG_SET_VSPE: + /* Assume all lanes have same drive settings. */ + data.set_vspe.swing = lt_settings->hw_lane_settings[0].VOLTAGE_SWING; + data.set_vspe.pre_emph = lt_settings->hw_lane_settings[0].PRE_EMPHASIS; + data.set_vspe.max_swing_reached = + lt_settings->hw_lane_settings[0].VOLTAGE_SWING == VOLTAGE_SWING_MAX_LEVEL ? 1 : 0; + data.set_vspe.max_pre_emph_reached = + lt_settings->hw_lane_settings[0].PRE_EMPHASIS == PRE_EMPHASIS_MAX_LEVEL ? 1 : 0; + break; + default: + ASSERT(false); /* Message type not supported by helper function. */ + break; + } + + return data.raw; +} + +/* Convert DC training pattern to DPIA training stage. */ +static enum dc_status convert_trng_ptn_to_trng_stg(enum dc_dp_training_pattern tps, enum dpia_set_config_ts *ts) +{ + enum dc_status status = DC_OK; + + switch (tps) { + case DP_TRAINING_PATTERN_SEQUENCE_1: + *ts = DPIA_TS_TPS1; + break; + case DP_TRAINING_PATTERN_SEQUENCE_2: + *ts = DPIA_TS_TPS2; + break; + case DP_TRAINING_PATTERN_SEQUENCE_3: + *ts = DPIA_TS_TPS3; + break; + case DP_TRAINING_PATTERN_SEQUENCE_4: + *ts = DPIA_TS_TPS4; + break; + case DP_TRAINING_PATTERN_VIDEOIDLE: + *ts = DPIA_TS_DPRX_DONE; + break; + default: /* TPS not supported by helper function. */ + ASSERT(false); + *ts = DPIA_TS_DPRX_DONE; + status = DC_UNSUPPORTED_VALUE; + break; + } + + return status; +} + +/* Write training pattern to DPCD. */ +static enum dc_status dpcd_set_lt_pattern( + struct dc_link *link, + enum dc_dp_training_pattern pattern, + uint32_t hop) +{ + union dpcd_training_pattern dpcd_pattern = {0}; + uint32_t dpcd_tps_offset = DP_TRAINING_PATTERN_SET; + enum dc_status status; + + if (hop != DPRX) + dpcd_tps_offset = DP_TRAINING_PATTERN_SET_PHY_REPEATER1 + + ((DP_REPEATER_CONFIGURATION_AND_STATUS_SIZE) * (hop - 1)); + + /* DpcdAddress_TrainingPatternSet */ + dpcd_pattern.v1_4.TRAINING_PATTERN_SET = + dp_training_pattern_to_dpcd_training_pattern(link, pattern); + + dpcd_pattern.v1_4.SCRAMBLING_DISABLE = + dp_initialize_scrambling_data_symbols(link, pattern); + + if (hop != DPRX) { + DC_LOG_HW_LINK_TRAINING("%s\n LTTPR Repeater ID: %d\n 0x%X pattern = %x\n", + __func__, + hop, + dpcd_tps_offset, + dpcd_pattern.v1_4.TRAINING_PATTERN_SET); + } else { + DC_LOG_HW_LINK_TRAINING("%s\n 0x%X pattern = %x\n", + __func__, + dpcd_tps_offset, + dpcd_pattern.v1_4.TRAINING_PATTERN_SET); + } + + status = core_link_write_dpcd( + link, + dpcd_tps_offset, + &dpcd_pattern.raw, + sizeof(dpcd_pattern.raw)); + + return status; +} + +/* Execute clock recovery phase of link training for specified hop in display + * path.in non-transparent mode: + * - Driver issues both DPCD and SET_CONFIG transactions. + * - TPS1 is transmitted for any hops downstream of DPOA. + * - Drive (VS/PE) only transmitted for the hop immediately downstream of DPOA. + * - CR for the first hop (DPTX-to-DPIA) is assumed to be successful. + * + * @param link DPIA link being trained. + * @param lt_settings link_setting and drive settings (voltage swing and pre-emphasis). + * @param hop Hop in display path. DPRX = 0. + */ +static enum link_training_result dpia_training_cr_non_transparent( + struct dc_link *link, + const struct link_resource *link_res, + struct link_training_settings *lt_settings, + uint32_t hop) +{ + enum link_training_result result = LINK_TRAINING_CR_FAIL_LANE0; + uint8_t repeater_cnt = 0; /* Number of hops/repeaters in display path. */ + enum dc_status status; + uint32_t retries_cr = 0; /* Number of consecutive attempts with same VS or PE. */ + uint32_t retry_count = 0; + uint32_t wait_time_microsec = TRAINING_AUX_RD_INTERVAL; /* From DP spec, CR read interval is always 100us. */ + enum dc_lane_count lane_count = lt_settings->link_settings.lane_count; + union lane_status dpcd_lane_status[LANE_COUNT_DP_MAX] = {0}; + union lane_align_status_updated dpcd_lane_status_updated = {0}; + union lane_adjust dpcd_lane_adjust[LANE_COUNT_DP_MAX] = {0}; + uint8_t set_cfg_data; + enum dpia_set_config_ts ts; + + repeater_cnt = dp_parse_lttpr_repeater_count(link->dpcd_caps.lttpr_caps.phy_repeater_cnt); + + /* Cap of LINK_TRAINING_MAX_CR_RETRY attempts at clock recovery. + * Fix inherited from perform_clock_recovery_sequence() - + * the DP equivalent of this function: + * Required for Synaptics MST hub which can put the LT in + * infinite loop by switching the VS between level 0 and level 1 + * continuously. + */ + while ((retries_cr < LINK_TRAINING_MAX_RETRY_COUNT) && + (retry_count < LINK_TRAINING_MAX_CR_RETRY)) { + + /* DPTX-to-DPIA */ + if (hop == repeater_cnt) { + /* Send SET_CONFIG(SET_LINK:LC,LR,LTTPR) to notify DPOA that + * non-transparent link training has started. + * This also enables the transmission of clk_sync packets. + */ + set_cfg_data = dpia_build_set_config_data( + DPIA_SET_CFG_SET_LINK, + link, + lt_settings); + status = core_link_send_set_config( + link, + DPIA_SET_CFG_SET_LINK, + set_cfg_data); + /* CR for this hop is considered successful as long as + * SET_CONFIG message is acknowledged by DPOA. + */ + if (status == DC_OK) + result = LINK_TRAINING_SUCCESS; + else + result = LINK_TRAINING_ABORT; + break; + } + + /* DPOA-to-x */ + /* Instruct DPOA to transmit TPS1 then update DPCD. */ + if (retry_count == 0) { + status = convert_trng_ptn_to_trng_stg(lt_settings->pattern_for_cr, &ts); + if (status != DC_OK) { + result = LINK_TRAINING_ABORT; + break; + } + status = core_link_send_set_config( + link, + DPIA_SET_CFG_SET_TRAINING, + ts); + if (status != DC_OK) { + result = LINK_TRAINING_ABORT; + break; + } + status = dpcd_set_lt_pattern(link, lt_settings->pattern_for_cr, hop); + if (status != DC_OK) { + result = LINK_TRAINING_ABORT; + break; + } + } + + /* Update DPOA drive settings then DPCD. DPOA does only adjusts + * drive settings for hops immediately downstream. + */ + if (hop == repeater_cnt - 1) { + set_cfg_data = dpia_build_set_config_data( + DPIA_SET_CFG_SET_VSPE, + link, + lt_settings); + status = core_link_send_set_config( + link, + DPIA_SET_CFG_SET_VSPE, + set_cfg_data); + if (status != DC_OK) { + result = LINK_TRAINING_ABORT; + break; + } + } + status = dpcd_set_lane_settings(link, lt_settings, hop); + if (status != DC_OK) { + result = LINK_TRAINING_ABORT; + break; + } + + dp_wait_for_training_aux_rd_interval(link, wait_time_microsec); + + /* Read status and adjustment requests from DPCD. */ + status = dp_get_lane_status_and_lane_adjust( + link, + lt_settings, + dpcd_lane_status, + &dpcd_lane_status_updated, + dpcd_lane_adjust, + hop); + if (status != DC_OK) { + result = LINK_TRAINING_ABORT; + break; + } + + /* Check if clock recovery successful. */ + if (dp_is_cr_done(lane_count, dpcd_lane_status)) { + result = LINK_TRAINING_SUCCESS; + break; + } + + result = dp_get_cr_failure(lane_count, dpcd_lane_status); + + if (dp_is_max_vs_reached(lt_settings)) + break; + + /* Count number of attempts with same drive 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) + && (lt_settings->dpcd_lane_settings[0].bits.PRE_EMPHASIS_SET == + dpcd_lane_adjust[0].bits.PRE_EMPHASIS_LANE)) + retries_cr++; + else + retries_cr = 0; + + /* Update VS/PE. */ + dp_decide_lane_settings(lt_settings, dpcd_lane_adjust, + lt_settings->hw_lane_settings, + lt_settings->dpcd_lane_settings); + retry_count++; + } + + /* Abort link training if clock recovery failed due to HPD unplug. */ + if (link->is_hpd_pending) + result = LINK_TRAINING_ABORT; + + DC_LOG_HW_LINK_TRAINING( + "%s\n DPIA(%d) clock recovery\n -hop(%d)\n - result(%d)\n - retries(%d)\n - status(%d)\n", + __func__, + link->link_id.enum_id - ENUM_ID_1, + hop, + result, + retry_count, + status); + + return result; +} + +/* Execute clock recovery phase of link training in transparent LTTPR mode: + * - Driver only issues DPCD transactions and leaves USB4 tunneling (SET_CONFIG) messages to DPIA. + * - Driver writes TPS1 to DPCD to kick off training. + * - Clock recovery (CR) for link is handled by DPOA, which reports result to DPIA on completion. + * - DPIA communicates result to driver by updating CR status when driver reads DPCD. + * + * @param link DPIA link being trained. + * @param lt_settings link_setting and drive settings (voltage swing and pre-emphasis). + */ +static enum link_training_result dpia_training_cr_transparent( + struct dc_link *link, + const struct link_resource *link_res, + struct link_training_settings *lt_settings) +{ + enum link_training_result result = LINK_TRAINING_CR_FAIL_LANE0; + enum dc_status status; + uint32_t retries_cr = 0; /* Number of consecutive attempts with same VS or PE. */ + uint32_t retry_count = 0; + uint32_t wait_time_microsec = lt_settings->cr_pattern_time; + enum dc_lane_count lane_count = lt_settings->link_settings.lane_count; + union lane_status dpcd_lane_status[LANE_COUNT_DP_MAX] = {0}; + union lane_align_status_updated dpcd_lane_status_updated = {0}; + union lane_adjust dpcd_lane_adjust[LANE_COUNT_DP_MAX] = {0}; + + /* Cap of LINK_TRAINING_MAX_CR_RETRY attempts at clock recovery. + * Fix inherited from perform_clock_recovery_sequence() - + * the DP equivalent of this function: + * Required for Synaptics MST hub which can put the LT in + * infinite loop by switching the VS between level 0 and level 1 + * continuously. + */ + while ((retries_cr < LINK_TRAINING_MAX_RETRY_COUNT) && + (retry_count < LINK_TRAINING_MAX_CR_RETRY)) { + + /* Write TPS1 (not VS or PE) to DPCD to start CR phase. + * DPIA sends SET_CONFIG(SET_LINK) to notify DPOA to + * start link training. + */ + if (retry_count == 0) { + status = dpcd_set_lt_pattern(link, lt_settings->pattern_for_cr, DPRX); + if (status != DC_OK) { + result = LINK_TRAINING_ABORT; + break; + } + } + + dp_wait_for_training_aux_rd_interval(link, wait_time_microsec); + + /* Read status and adjustment requests from DPCD. */ + status = dp_get_lane_status_and_lane_adjust( + link, + lt_settings, + dpcd_lane_status, + &dpcd_lane_status_updated, + dpcd_lane_adjust, + DPRX); + if (status != DC_OK) { + result = LINK_TRAINING_ABORT; + break; + } + + /* Check if clock recovery successful. */ + if (dp_is_cr_done(lane_count, dpcd_lane_status)) { + result = LINK_TRAINING_SUCCESS; + break; + } + + result = dp_get_cr_failure(lane_count, dpcd_lane_status); + + if (dp_is_max_vs_reached(lt_settings)) + break; + + /* Count number of attempts with same drive 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) + && (lt_settings->dpcd_lane_settings[0].bits.PRE_EMPHASIS_SET == + dpcd_lane_adjust[0].bits.PRE_EMPHASIS_LANE)) + retries_cr++; + else + retries_cr = 0; + + /* Update VS/PE. */ + dp_decide_lane_settings(lt_settings, dpcd_lane_adjust, + lt_settings->hw_lane_settings, lt_settings->dpcd_lane_settings); + retry_count++; + } + + /* Abort link training if clock recovery failed due to HPD unplug. */ + if (link->is_hpd_pending) + result = LINK_TRAINING_ABORT; + + DC_LOG_HW_LINK_TRAINING("%s\n DPIA(%d) clock recovery\n -hop(%d)\n - result(%d)\n - retries(%d)\n", + __func__, + link->link_id.enum_id - ENUM_ID_1, + DPRX, + result, + retry_count); + + return result; +} + +/* Execute clock recovery phase of link training for specified hop in display + * path. + * + * @param link DPIA link being trained. + * @param lt_settings link_setting and drive settings (voltage swing and pre-emphasis). + * @param hop Hop in display path. DPRX = 0. + */ +static enum link_training_result dpia_training_cr_phase( + struct dc_link *link, + const struct link_resource *link_res, + struct link_training_settings *lt_settings, + uint32_t hop) +{ + enum link_training_result result = LINK_TRAINING_CR_FAIL_LANE0; + + if (lt_settings->lttpr_mode == LTTPR_MODE_NON_TRANSPARENT) + result = dpia_training_cr_non_transparent(link, link_res, lt_settings, hop); + else + result = dpia_training_cr_transparent(link, link_res, lt_settings); + + return result; +} + +/* Return status read interval during equalization phase. */ +static uint32_t dpia_get_eq_aux_rd_interval( + const struct dc_link *link, + const struct link_training_settings *lt_settings, + uint32_t hop) +{ + uint32_t wait_time_microsec; + + if (hop == DPRX) + wait_time_microsec = lt_settings->eq_pattern_time; + else + wait_time_microsec = + dp_translate_training_aux_read_interval( + link->dpcd_caps.lttpr_caps.aux_rd_interval[hop - 1]); + + /* Check debug option for extending aux read interval. */ + if (link->dc->debug.dpia_debug.bits.extend_aux_rd_interval) + wait_time_microsec = DPIA_DEBUG_EXTENDED_AUX_RD_INTERVAL_US; + + return wait_time_microsec; +} + +/* Execute equalization phase of link training for specified hop in display + * path in non-transparent mode: + * - driver issues both DPCD and SET_CONFIG transactions. + * - TPSx is transmitted for any hops downstream of DPOA. + * - Drive (VS/PE) only transmitted for the hop immediately downstream of DPOA. + * - EQ for the first hop (DPTX-to-DPIA) is assumed to be successful. + * - DPRX EQ only reported successful when both DPRX and DPIA requirements (clk sync packets sent) fulfilled. + * + * @param link DPIA link being trained. + * @param lt_settings link_setting and drive settings (voltage swing and pre-emphasis). + * @param hop Hop in display path. DPRX = 0. + */ +static enum link_training_result dpia_training_eq_non_transparent( + struct dc_link *link, + const struct link_resource *link_res, + struct link_training_settings *lt_settings, + uint32_t hop) +{ + enum link_training_result result = LINK_TRAINING_EQ_FAIL_EQ; + uint8_t repeater_cnt = 0; /* Number of hops/repeaters in display path. */ + uint32_t retries_eq = 0; + enum dc_status status; + enum dc_dp_training_pattern tr_pattern; + 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}; + uint8_t set_cfg_data; + enum dpia_set_config_ts ts; + + /* Training pattern is TPS4 for repeater; + * TPS2/3/4 for DPRX depending on what it supports. + */ + if (hop == DPRX) + tr_pattern = lt_settings->pattern_for_eq; + else + tr_pattern = DP_TRAINING_PATTERN_SEQUENCE_4; + + repeater_cnt = dp_parse_lttpr_repeater_count(link->dpcd_caps.lttpr_caps.phy_repeater_cnt); + + for (retries_eq = 0; retries_eq < LINK_TRAINING_MAX_RETRY_COUNT; retries_eq++) { + + /* DPTX-to-DPIA equalization always successful. */ + if (hop == repeater_cnt) { + result = LINK_TRAINING_SUCCESS; + break; + } + + /* Instruct DPOA to transmit TPSn then update DPCD. */ + if (retries_eq == 0) { + status = convert_trng_ptn_to_trng_stg(tr_pattern, &ts); + if (status != DC_OK) { + result = LINK_TRAINING_ABORT; + break; + } + status = core_link_send_set_config( + link, + DPIA_SET_CFG_SET_TRAINING, + ts); + if (status != DC_OK) { + result = LINK_TRAINING_ABORT; + break; + } + status = dpcd_set_lt_pattern(link, tr_pattern, hop); + if (status != DC_OK) { + result = LINK_TRAINING_ABORT; + break; + } + } + + /* Update DPOA drive settings then DPCD. DPOA only adjusts + * drive settings for hop immediately downstream. + */ + if (hop == repeater_cnt - 1) { + set_cfg_data = dpia_build_set_config_data( + DPIA_SET_CFG_SET_VSPE, + link, + lt_settings); + status = core_link_send_set_config( + link, + DPIA_SET_CFG_SET_VSPE, + set_cfg_data); + if (status != DC_OK) { + result = LINK_TRAINING_ABORT; + break; + } + } + status = dpcd_set_lane_settings(link, lt_settings, hop); + if (status != DC_OK) { + result = LINK_TRAINING_ABORT; + break; + } + + /* Extend wait time on second equalisation attempt on final hop to + * ensure clock sync packets have been sent. + */ + if (hop == DPRX && retries_eq == 1) + wait_time_microsec = max(wait_time_microsec, (uint32_t) DPIA_CLK_SYNC_DELAY); + else + wait_time_microsec = dpia_get_eq_aux_rd_interval(link, lt_settings, hop); + + dp_wait_for_training_aux_rd_interval(link, wait_time_microsec); + + /* Read status and adjustment requests from DPCD. */ + status = dp_get_lane_status_and_lane_adjust( + link, + lt_settings, + dpcd_lane_status, + &dpcd_lane_status_updated, + dpcd_lane_adjust, + hop); + if (status != DC_OK) { + result = LINK_TRAINING_ABORT; + break; + } + + /* CR can still fail during EQ phase. Fail training if CR fails. */ + if (!dp_is_cr_done(lane_count, dpcd_lane_status)) { + result = LINK_TRAINING_EQ_FAIL_CR; + break; + } + + if (dp_is_ch_eq_done(lane_count, dpcd_lane_status) && + dp_is_symbol_locked(link->cur_link_settings.lane_count, dpcd_lane_status) && + dp_is_interlane_aligned(dpcd_lane_status_updated)) { + result = LINK_TRAINING_SUCCESS; + break; + } + + /* Update VS/PE. */ + dp_decide_lane_settings(lt_settings, dpcd_lane_adjust, + lt_settings->hw_lane_settings, lt_settings->dpcd_lane_settings); + } + + /* Abort link training if equalization failed due to HPD unplug. */ + if (link->is_hpd_pending) + result = LINK_TRAINING_ABORT; + + DC_LOG_HW_LINK_TRAINING( + "%s\n DPIA(%d) equalization\n - hop(%d)\n - result(%d)\n - retries(%d)\n - status(%d)\n", + __func__, + link->link_id.enum_id - ENUM_ID_1, + hop, + result, + retries_eq, + status); + + return result; +} + +/* Execute equalization phase of link training for specified hop in display + * path in transparent LTTPR mode: + * - driver only issues DPCD transactions leaves USB4 tunneling (SET_CONFIG) messages to DPIA. + * - driver writes TPSx to DPCD to notify DPIA that is in equalization phase. + * - equalization (EQ) for link is handled by DPOA, which reports result to DPIA on completion. + * - DPIA communicates result to driver by updating EQ status when driver reads DPCD. + * + * @param link DPIA link being trained. + * @param lt_settings link_setting and drive settings (voltage swing and pre-emphasis). + * @param hop Hop in display path. DPRX = 0. + */ +static enum link_training_result dpia_training_eq_transparent( + struct dc_link *link, + const struct link_resource *link_res, + struct link_training_settings *lt_settings) +{ + enum link_training_result result = LINK_TRAINING_EQ_FAIL_EQ; + uint32_t retries_eq = 0; + enum dc_status status; + enum dc_dp_training_pattern tr_pattern = lt_settings->pattern_for_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}; + + wait_time_microsec = dpia_get_eq_aux_rd_interval(link, lt_settings, DPRX); + + for (retries_eq = 0; retries_eq < LINK_TRAINING_MAX_RETRY_COUNT; retries_eq++) { + + if (retries_eq == 0) { + status = dpcd_set_lt_pattern(link, tr_pattern, DPRX); + if (status != DC_OK) { + result = LINK_TRAINING_ABORT; + break; + } + } + + dp_wait_for_training_aux_rd_interval(link, wait_time_microsec); + + /* Read status and adjustment requests from DPCD. */ + status = dp_get_lane_status_and_lane_adjust( + link, + lt_settings, + dpcd_lane_status, + &dpcd_lane_status_updated, + dpcd_lane_adjust, + DPRX); + if (status != DC_OK) { + result = LINK_TRAINING_ABORT; + break; + } + + /* CR can still fail during EQ phase. Fail training if CR fails. */ + if (!dp_is_cr_done(lane_count, dpcd_lane_status)) { + result = LINK_TRAINING_EQ_FAIL_CR; + break; + } + + if (dp_is_ch_eq_done(lane_count, dpcd_lane_status) && + dp_is_symbol_locked(link->cur_link_settings.lane_count, dpcd_lane_status)) { + /* Take into consideration corner case for DP 1.4a LL Compliance CTS as USB4 + * has to share encoders unlike DP and USBC + */ + if (dp_is_interlane_aligned(dpcd_lane_status_updated) || (link->is_automated && retries_eq)) { + result = LINK_TRAINING_SUCCESS; + break; + } + } + + /* Update VS/PE. */ + dp_decide_lane_settings(lt_settings, dpcd_lane_adjust, + lt_settings->hw_lane_settings, lt_settings->dpcd_lane_settings); + } + + /* Abort link training if equalization failed due to HPD unplug. */ + if (link->is_hpd_pending) + result = LINK_TRAINING_ABORT; + + DC_LOG_HW_LINK_TRAINING("%s\n DPIA(%d) equalization\n - hop(%d)\n - result(%d)\n - retries(%d)\n", + __func__, + link->link_id.enum_id - ENUM_ID_1, + DPRX, + result, + retries_eq); + + return result; +} + +/* Execute equalization phase of link training for specified hop in display + * path. + * + * @param link DPIA link being trained. + * @param lt_settings link_setting and drive settings (voltage swing and pre-emphasis). + * @param hop Hop in display path. DPRX = 0. + */ +static enum link_training_result dpia_training_eq_phase( + struct dc_link *link, + const struct link_resource *link_res, + struct link_training_settings *lt_settings, + uint32_t hop) +{ + enum link_training_result result; + + if (lt_settings->lttpr_mode == LTTPR_MODE_NON_TRANSPARENT) + result = dpia_training_eq_non_transparent(link, link_res, lt_settings, hop); + else + result = dpia_training_eq_transparent(link, link_res, lt_settings); + + return result; +} + +/* End training of specified hop in display path. */ +static enum dc_status dpcd_clear_lt_pattern( + struct dc_link *link, + uint32_t hop) +{ + union dpcd_training_pattern dpcd_pattern = {0}; + uint32_t dpcd_tps_offset = DP_TRAINING_PATTERN_SET; + enum dc_status status; + + if (hop != DPRX) + dpcd_tps_offset = DP_TRAINING_PATTERN_SET_PHY_REPEATER1 + + ((DP_REPEATER_CONFIGURATION_AND_STATUS_SIZE) * (hop - 1)); + + status = core_link_write_dpcd( + link, + dpcd_tps_offset, + &dpcd_pattern.raw, + sizeof(dpcd_pattern.raw)); + + return status; +} + +/* End training of specified hop in display path. + * + * In transparent LTTPR mode: + * - driver clears training pattern for the specified hop in DPCD. + * In non-transparent LTTPR mode: + * - in addition to clearing training pattern, driver issues USB4 tunneling + * (SET_CONFIG) messages to notify DPOA when training is done for first hop + * (DPTX-to-DPIA) and last hop (DPRX). + * + * @param link DPIA link being trained. + * @param hop Hop in display path. DPRX = 0. + */ +static enum link_training_result dpia_training_end( + struct dc_link *link, + struct link_training_settings *lt_settings, + uint32_t hop) +{ + enum link_training_result result = LINK_TRAINING_SUCCESS; + uint8_t repeater_cnt = 0; /* Number of hops/repeaters in display path. */ + enum dc_status status; + + if (lt_settings->lttpr_mode == LTTPR_MODE_NON_TRANSPARENT) { + + repeater_cnt = dp_parse_lttpr_repeater_count(link->dpcd_caps.lttpr_caps.phy_repeater_cnt); + + if (hop == repeater_cnt) { /* DPTX-to-DPIA */ + /* Send SET_CONFIG(SET_TRAINING:0xff) to notify DPOA that + * DPTX-to-DPIA hop trained. No DPCD write needed for first hop. + */ + status = core_link_send_set_config( + link, + DPIA_SET_CFG_SET_TRAINING, + DPIA_TS_UFP_DONE); + if (status != DC_OK) + result = LINK_TRAINING_ABORT; + } else { /* DPOA-to-x */ + /* Write 0x0 to TRAINING_PATTERN_SET */ + status = dpcd_clear_lt_pattern(link, hop); + if (status != DC_OK) + result = LINK_TRAINING_ABORT; + } + + /* Notify DPOA that non-transparent link training of DPRX done. */ + if (hop == DPRX && result != LINK_TRAINING_ABORT) { + status = core_link_send_set_config( + link, + DPIA_SET_CFG_SET_TRAINING, + DPIA_TS_DPRX_DONE); + if (status != DC_OK) + result = LINK_TRAINING_ABORT; + } + + } else { /* non-LTTPR or transparent LTTPR. */ + + /* Write 0x0 to TRAINING_PATTERN_SET */ + status = dpcd_clear_lt_pattern(link, hop); + if (status != DC_OK) + result = LINK_TRAINING_ABORT; + + } + + DC_LOG_HW_LINK_TRAINING("%s\n DPIA(%d) end\n - hop(%d)\n - result(%d)\n - LTTPR mode(%d)\n", + __func__, + link->link_id.enum_id - ENUM_ID_1, + hop, + result, + lt_settings->lttpr_mode); + + return result; +} + +/* When aborting training of specified hop in display path, clean up by: + * - Attempting to clear DPCD TRAINING_PATTERN_SET, LINK_BW_SET and LANE_COUNT_SET. + * - Sending SET_CONFIG(SET_LINK) with lane count and link rate set to 0. + * + * @param link DPIA link being trained. + * @param hop Hop in display path. DPRX = 0. + */ +static void dpia_training_abort( + struct dc_link *link, + struct link_training_settings *lt_settings, + uint32_t hop) +{ + uint8_t data = 0; + uint32_t dpcd_tps_offset = DP_TRAINING_PATTERN_SET; + + DC_LOG_HW_LINK_TRAINING("%s\n DPIA(%d) aborting\n - LTTPR mode(%d)\n - HPD(%d)\n", + __func__, + link->link_id.enum_id - ENUM_ID_1, + lt_settings->lttpr_mode, + link->is_hpd_pending); + + /* Abandon clean-up if sink unplugged. */ + if (link->is_hpd_pending) + return; + + if (hop != DPRX) + dpcd_tps_offset = DP_TRAINING_PATTERN_SET_PHY_REPEATER1 + + ((DP_REPEATER_CONFIGURATION_AND_STATUS_SIZE) * (hop - 1)); + + core_link_write_dpcd(link, dpcd_tps_offset, &data, 1); + core_link_write_dpcd(link, DP_LINK_BW_SET, &data, 1); + core_link_write_dpcd(link, DP_LANE_COUNT_SET, &data, 1); + core_link_send_set_config(link, DPIA_SET_CFG_SET_LINK, data); +} + +enum link_training_result dc_link_dpia_perform_link_training( + struct dc_link *link, + const struct link_resource *link_res, + const struct dc_link_settings *link_setting, + bool skip_video_pattern) +{ + enum link_training_result result; + struct link_training_settings lt_settings = {0}; + uint8_t repeater_cnt = 0; /* Number of hops/repeaters in display path. */ + int8_t repeater_id; /* Current hop. */ + + struct dc_link_settings link_settings = *link_setting; // non-const copy to pass in + + lt_settings.lttpr_mode = dc_link_decide_lttpr_mode(link, &link_settings); + + /* Configure link as prescribed in link_setting and set LTTPR mode. */ + result = dpia_configure_link(link, link_res, link_setting, <_settings); + if (result != LINK_TRAINING_SUCCESS) + return result; + + if (lt_settings.lttpr_mode == LTTPR_MODE_NON_TRANSPARENT) + repeater_cnt = dp_parse_lttpr_repeater_count(link->dpcd_caps.lttpr_caps.phy_repeater_cnt); + + /* Train each hop in turn starting with the one closest to DPTX. + * In transparent or non-LTTPR mode, train only the final hop (DPRX). + */ + for (repeater_id = repeater_cnt; repeater_id >= 0; repeater_id--) { + /* Clock recovery. */ + result = dpia_training_cr_phase(link, link_res, <_settings, repeater_id); + if (result != LINK_TRAINING_SUCCESS) + break; + + /* Equalization. */ + result = dpia_training_eq_phase(link, link_res, <_settings, repeater_id); + if (result != LINK_TRAINING_SUCCESS) + break; + + /* Stop training hop. */ + result = dpia_training_end(link, <_settings, repeater_id); + if (result != LINK_TRAINING_SUCCESS) + break; + } + + /* Double-check link status if training successful; gracefully abort + * training of current hop if training failed due to message tunneling + * failure; end training of hop if training ended conventionally and + * falling back to lower bandwidth settings possible. + */ + if (result == LINK_TRAINING_SUCCESS) { + msleep(5); + if (!link->is_automated) + result = dp_check_link_loss_status(link, <_settings); + } else if (result == LINK_TRAINING_ABORT) + dpia_training_abort(link, <_settings, repeater_id); + else + dpia_training_end(link, <_settings, repeater_id); + + return result; +} |