diff options
Diffstat (limited to 'drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_phy.c')
-rw-r--r-- | drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_phy.c | 209 |
1 files changed, 209 insertions, 0 deletions
diff --git a/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_phy.c b/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_phy.c new file mode 100644 index 0000000000..0050e0a06c --- /dev/null +++ b/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_phy.c @@ -0,0 +1,209 @@ +/* + * 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 file implements basic dp phy functionality such as enable/disable phy + * output and set lane/drive settings. This file is responsible for maintaining + * and update software state representing current phy status such as current + * link settings. + */ + +#include "link_dp_phy.h" +#include "link_dpcd.h" +#include "link_dp_training.h" +#include "link_dp_capability.h" +#include "clk_mgr.h" +#include "resource.h" +#include "link_enc_cfg.h" +#define DC_LOGGER \ + link->ctx->logger + +void dpcd_write_rx_power_ctrl(struct dc_link *link, bool on) +{ + uint8_t state; + + state = on ? DP_POWER_STATE_D0 : DP_POWER_STATE_D3; + + if (link->sync_lt_in_progress) + return; + + core_link_write_dpcd(link, DP_SET_POWER, &state, + sizeof(state)); + +} + +void dp_enable_link_phy( + struct dc_link *link, + const struct link_resource *link_res, + enum signal_type signal, + enum clock_source_id clock_source, + const struct dc_link_settings *link_settings) +{ + link->cur_link_settings = *link_settings; + link->dc->hwss.enable_dp_link_output(link, link_res, signal, + clock_source, link_settings); + dpcd_write_rx_power_ctrl(link, true); +} + +void dp_disable_link_phy(struct dc_link *link, + const struct link_resource *link_res, + enum signal_type signal) +{ + struct dc *dc = link->ctx->dc; + + if (!link->wa_flags.dp_keep_receiver_powered && + !link->skip_implict_edp_power_control) + dpcd_write_rx_power_ctrl(link, false); + + dc->hwss.disable_link_output(link, link_res, signal); + /* Clear current link setting.*/ + memset(&link->cur_link_settings, 0, + sizeof(link->cur_link_settings)); + + if (dc->clk_mgr->funcs->notify_link_rate_change) + dc->clk_mgr->funcs->notify_link_rate_change(dc->clk_mgr, link); +} + +static inline bool is_immediate_downstream(struct dc_link *link, uint32_t offset) +{ + return (dp_parse_lttpr_repeater_count(link->dpcd_caps.lttpr_caps.phy_repeater_cnt) == + offset); +} + +void dp_set_hw_lane_settings( + struct dc_link *link, + const struct link_resource *link_res, + const struct link_training_settings *link_settings, + uint32_t offset) +{ + const struct link_hwss *link_hwss = get_link_hwss(link, link_res); + + if ((link_settings->lttpr_mode == LTTPR_MODE_NON_TRANSPARENT) && + !is_immediate_downstream(link, offset)) + return; + + if (link_hwss->ext.set_dp_lane_settings) + link_hwss->ext.set_dp_lane_settings(link, link_res, + &link_settings->link_settings, + link_settings->hw_lane_settings); + + memmove(link->cur_lane_setting, + link_settings->hw_lane_settings, + sizeof(link->cur_lane_setting)); +} + +void dp_set_drive_settings( + struct dc_link *link, + const struct link_resource *link_res, + struct link_training_settings *lt_settings) +{ + /* program ASIC PHY settings*/ + dp_set_hw_lane_settings(link, link_res, lt_settings, DPRX); + + dp_hw_to_dpcd_lane_settings(lt_settings, + lt_settings->hw_lane_settings, + lt_settings->dpcd_lane_settings); + + /* Notify DP sink the PHY settings from source */ + dpcd_set_lane_settings(link, lt_settings, DPRX); +} + +enum dc_status dp_set_fec_ready(struct dc_link *link, const struct link_resource *link_res, bool ready) +{ + /* FEC has to be "set ready" before the link training. + * The policy is to always train with FEC + * if the sink supports it and leave it enabled on link. + * If FEC is not supported, disable it. + */ + struct link_encoder *link_enc = NULL; + enum dc_status status = DC_OK; + uint8_t fec_config = 0; + + link_enc = link_enc_cfg_get_link_enc(link); + ASSERT(link_enc); + + if (!dp_should_enable_fec(link)) + return status; + + if (link_enc->funcs->fec_set_ready && + link->dpcd_caps.fec_cap.bits.FEC_CAPABLE) { + if (ready) { + fec_config = 1; + status = core_link_write_dpcd(link, + DP_FEC_CONFIGURATION, + &fec_config, + sizeof(fec_config)); + if (status == DC_OK) { + link_enc->funcs->fec_set_ready(link_enc, true); + link->fec_state = dc_link_fec_ready; + } else { + link_enc->funcs->fec_set_ready(link_enc, false); + link->fec_state = dc_link_fec_not_ready; + dm_error("dpcd write failed to set fec_ready"); + } + } else if (link->fec_state == dc_link_fec_ready) { + fec_config = 0; + status = core_link_write_dpcd(link, + DP_FEC_CONFIGURATION, + &fec_config, + sizeof(fec_config)); + link_enc->funcs->fec_set_ready(link_enc, false); + link->fec_state = dc_link_fec_not_ready; + } + } + + return status; +} + +void dp_set_fec_enable(struct dc_link *link, bool enable) +{ + struct link_encoder *link_enc = NULL; + + link_enc = link_enc_cfg_get_link_enc(link); + ASSERT(link_enc); + + if (!dp_should_enable_fec(link)) + return; + + if (link_enc->funcs->fec_set_enable && + link->dpcd_caps.fec_cap.bits.FEC_CAPABLE) { + if (link->fec_state == dc_link_fec_ready && enable) { + /* Accord to DP spec, FEC enable sequence can first + * be transmitted anytime after 1000 LL codes have + * been transmitted on the link after link training + * completion. Using 1 lane RBR should have the maximum + * time for transmitting 1000 LL codes which is 6.173 us. + * So use 7 microseconds delay instead. + */ + udelay(7); + link_enc->funcs->fec_set_enable(link_enc, true); + link->fec_state = dc_link_fec_enabled; + } else if (link->fec_state == dc_link_fec_enabled && !enable) { + link_enc->funcs->fec_set_enable(link_enc, false); + link->fec_state = dc_link_fec_ready; + } + } +} + |