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path: root/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_phy.c
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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.c209
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;
+ }
+ }
+}
+