From: Michael Strauss Date: Fri, 24 Mar 2023 14:48:37 +0000 (-0400) Subject: drm/amd/display: Improve robustness of FIXED_VS link training at DP1 rates X-Git-Tag: v6.6.17~4917^2~7^2~51 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=7727e7b60f82e8265a1061b81379f5a7bce0dba6;p=platform%2Fkernel%2Flinux-rpi.git drm/amd/display: Improve robustness of FIXED_VS link training at DP1 rates [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 Acked-by: Qingqing Zhuo Signed-off-by: Michael Strauss Tested-by: Daniel Wheeler Signed-off-by: Alex Deucher --- diff --git a/drivers/gpu/drm/amd/display/dc/dc.h b/drivers/gpu/drm/amd/display/dc/dc.h index f51b9c2..190e6a2 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 eaaa2e0..ff8cd50 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 f6c5ee2..027ad1f 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 f301c9e..70fc0dd 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, <_settings); + if (link->dc->config.use_old_fixed_vs_sequence) + status = dp_perform_fixed_vs_pe_training_sequence_legacy(link, link_res, <_settings); + else + status = dp_perform_fixed_vs_pe_training_sequence(link, link_res, <_settings); else if (encoding == DP_8b_10b_ENCODING) status = dp_perform_8b_10b_link_training(link, link_res, <_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 a4071d2..5731c4b 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(<_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(<_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 e61970e..c0d6ea3 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,