drm/amdgpu: add core driver (v4)

This adds the non-asic specific core driver code.

v2: remove extra kconfig option
v3: implement minor fixes from Fengguang Wu
v4: fix cast in amdgpu_ucode.c

Acked-by: Christian König <christian.koenig@amd.com>
Acked-by: Jammy Zhou <Jammy.Zhou@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

1 files changed, 774 insertions, 0 deletions

diff --git a/drivers/gpu/drm/amd/amdgpu/atombios_dp.c b/drivers/gpu/drm/amd/amdgpu/atombios_dp.c
new file mode 100644
index 000000000000..e00b8adde18d
--- /dev/null
+++ b/drivers/gpu/drm/amd/amdgpu/atombios_dp.c
@@ -0,0 +1,774 @@
+/*
+ * Copyright 2007-8 Advanced Micro Devices, Inc.
+ * Copyright 2008 Red Hat 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: Dave Airlie
+ *          Alex Deucher
+ *          Jerome Glisse
+ */
+#include <drm/drmP.h>
+#include <drm/amdgpu_drm.h>
+#include "amdgpu.h"
+
+#include "atom.h"
+#include "atom-bits.h"
+#include "atombios_encoders.h"
+#include "atombios_dp.h"
+#include "amdgpu_connectors.h"
+#include "amdgpu_atombios.h"
+#include <drm/drm_dp_helper.h>
+
+/* move these to drm_dp_helper.c/h */
+#define DP_LINK_CONFIGURATION_SIZE 9
+#define DP_DPCD_SIZE DP_RECEIVER_CAP_SIZE
+
+static char *voltage_names[] = {
+	"0.4V", "0.6V", "0.8V", "1.2V"
+};
+static char *pre_emph_names[] = {
+	"0dB", "3.5dB", "6dB", "9.5dB"
+};
+
+/***** amdgpu AUX functions *****/
+
+union aux_channel_transaction {
+	PROCESS_AUX_CHANNEL_TRANSACTION_PS_ALLOCATION v1;
+	PROCESS_AUX_CHANNEL_TRANSACTION_PARAMETERS_V2 v2;
+};
+
+static int amdgpu_atombios_dp_process_aux_ch(struct amdgpu_i2c_chan *chan,
+				      u8 *send, int send_bytes,
+				      u8 *recv, int recv_size,
+				      u8 delay, u8 *ack)
+{
+	struct drm_device *dev = chan->dev;
+	struct amdgpu_device *adev = dev->dev_private;
+	union aux_channel_transaction args;
+	int index = GetIndexIntoMasterTable(COMMAND, ProcessAuxChannelTransaction);
+	unsigned char *base;
+	int recv_bytes;
+	int r = 0;
+
+	memset(&args, 0, sizeof(args));
+
+	mutex_lock(&chan->mutex);
+
+	base = (unsigned char *)(adev->mode_info.atom_context->scratch + 1);
+
+	amdgpu_atombios_copy_swap(base, send, send_bytes, true);
+
+	args.v2.lpAuxRequest = cpu_to_le16((u16)(0 + 4));
+	args.v2.lpDataOut = cpu_to_le16((u16)(16 + 4));
+	args.v2.ucDataOutLen = 0;
+	args.v2.ucChannelID = chan->rec.i2c_id;
+	args.v2.ucDelay = delay / 10;
+	args.v2.ucHPD_ID = chan->rec.hpd;
+
+	amdgpu_atom_execute_table(adev->mode_info.atom_context, index, (uint32_t *)&args);
+
+	*ack = args.v2.ucReplyStatus;
+
+	/* timeout */
+	if (args.v2.ucReplyStatus == 1) {
+		DRM_DEBUG_KMS("dp_aux_ch timeout\n");
+		r = -ETIMEDOUT;
+		goto done;
+	}
+
+	/* flags not zero */
+	if (args.v2.ucReplyStatus == 2) {
+		DRM_DEBUG_KMS("dp_aux_ch flags not zero\n");
+		r = -EIO;
+		goto done;
+	}
+
+	/* error */
+	if (args.v2.ucReplyStatus == 3) {
+		DRM_DEBUG_KMS("dp_aux_ch error\n");
+		r = -EIO;
+		goto done;
+	}
+
+	recv_bytes = args.v1.ucDataOutLen;
+	if (recv_bytes > recv_size)
+		recv_bytes = recv_size;
+
+	if (recv && recv_size)
+		amdgpu_atombios_copy_swap(recv, base + 16, recv_bytes, false);
+
+	r = recv_bytes;
+done:
+	mutex_unlock(&chan->mutex);
+
+	return r;
+}
+
+#define BARE_ADDRESS_SIZE 3
+#define HEADER_SIZE (BARE_ADDRESS_SIZE + 1)
+
+static ssize_t
+amdgpu_atombios_dp_aux_transfer(struct drm_dp_aux *aux, struct drm_dp_aux_msg *msg)
+{
+	struct amdgpu_i2c_chan *chan =
+		container_of(aux, struct amdgpu_i2c_chan, aux);
+	int ret;
+	u8 tx_buf[20];
+	size_t tx_size;
+	u8 ack, delay = 0;
+
+	if (WARN_ON(msg->size > 16))
+		return -E2BIG;
+
+	tx_buf[0] = msg->address & 0xff;
+	tx_buf[1] = msg->address >> 8;
+	tx_buf[2] = msg->request << 4;
+	tx_buf[3] = msg->size ? (msg->size - 1) : 0;
+
+	switch (msg->request & ~DP_AUX_I2C_MOT) {
+	case DP_AUX_NATIVE_WRITE:
+	case DP_AUX_I2C_WRITE:
+		/* tx_size needs to be 4 even for bare address packets since the atom
+		 * table needs the info in tx_buf[3].
+		 */
+		tx_size = HEADER_SIZE + msg->size;
+		if (msg->size == 0)
+			tx_buf[3] |= BARE_ADDRESS_SIZE << 4;
+		else
+			tx_buf[3] |= tx_size << 4;
+		memcpy(tx_buf + HEADER_SIZE, msg->buffer, msg->size);
+		ret = amdgpu_atombios_dp_process_aux_ch(chan,
+						 tx_buf, tx_size, NULL, 0, delay, &ack);
+		if (ret >= 0)
+			/* Return payload size. */
+			ret = msg->size;
+		break;
+	case DP_AUX_NATIVE_READ:
+	case DP_AUX_I2C_READ:
+		/* tx_size needs to be 4 even for bare address packets since the atom
+		 * table needs the info in tx_buf[3].
+		 */
+		tx_size = HEADER_SIZE;
+		if (msg->size == 0)
+			tx_buf[3] |= BARE_ADDRESS_SIZE << 4;
+		else
+			tx_buf[3] |= tx_size << 4;
+		ret = amdgpu_atombios_dp_process_aux_ch(chan,
+						 tx_buf, tx_size, msg->buffer, msg->size, delay, &ack);
+		break;
+	default:
+		ret = -EINVAL;
+		break;
+	}
+
+	if (ret >= 0)
+		msg->reply = ack >> 4;
+
+	return ret;
+}
+
+void amdgpu_atombios_dp_aux_init(struct amdgpu_connector *amdgpu_connector)
+{
+	int ret;
+
+	amdgpu_connector->ddc_bus->rec.hpd = amdgpu_connector->hpd.hpd;
+	amdgpu_connector->ddc_bus->aux.dev = amdgpu_connector->base.kdev;
+	amdgpu_connector->ddc_bus->aux.transfer = amdgpu_atombios_dp_aux_transfer;
+	ret = drm_dp_aux_register(&amdgpu_connector->ddc_bus->aux);
+	if (!ret)
+		amdgpu_connector->ddc_bus->has_aux = true;
+
+	WARN(ret, "drm_dp_aux_register_i2c_bus() failed with error %d\n", ret);
+}
+
+/***** general DP utility functions *****/
+
+#define DP_VOLTAGE_MAX         DP_TRAIN_VOLTAGE_SWING_LEVEL_3
+#define DP_PRE_EMPHASIS_MAX    DP_TRAIN_PRE_EMPH_LEVEL_3
+
+static void amdgpu_atombios_dp_get_adjust_train(u8 link_status[DP_LINK_STATUS_SIZE],
+					 int lane_count,
+					 u8 train_set[4])
+{
+	u8 v = 0;
+	u8 p = 0;
+	int lane;
+
+	for (lane = 0; lane < lane_count; lane++) {
+		u8 this_v = drm_dp_get_adjust_request_voltage(link_status, lane);
+		u8 this_p = drm_dp_get_adjust_request_pre_emphasis(link_status, lane);
+
+		DRM_DEBUG_KMS("requested signal parameters: lane %d voltage %s pre_emph %s\n",
+			  lane,
+			  voltage_names[this_v >> DP_TRAIN_VOLTAGE_SWING_SHIFT],
+			  pre_emph_names[this_p >> DP_TRAIN_PRE_EMPHASIS_SHIFT]);
+
+		if (this_v > v)
+			v = this_v;
+		if (this_p > p)
+			p = this_p;
+	}
+
+	if (v >= DP_VOLTAGE_MAX)
+		v |= DP_TRAIN_MAX_SWING_REACHED;
+
+	if (p >= DP_PRE_EMPHASIS_MAX)
+		p |= DP_TRAIN_MAX_PRE_EMPHASIS_REACHED;
+
+	DRM_DEBUG_KMS("using signal parameters: voltage %s pre_emph %s\n",
+		  voltage_names[(v & DP_TRAIN_VOLTAGE_SWING_MASK) >> DP_TRAIN_VOLTAGE_SWING_SHIFT],
+		  pre_emph_names[(p & DP_TRAIN_PRE_EMPHASIS_MASK) >> DP_TRAIN_PRE_EMPHASIS_SHIFT]);
+
+	for (lane = 0; lane < 4; lane++)
+		train_set[lane] = v | p;
+}
+
+/* convert bits per color to bits per pixel */
+/* get bpc from the EDID */
+static int amdgpu_atombios_dp_convert_bpc_to_bpp(int bpc)
+{
+	if (bpc == 0)
+		return 24;
+	else
+		return bpc * 3;
+}
+
+/* get the max pix clock supported by the link rate and lane num */
+static int amdgpu_atombios_dp_get_max_dp_pix_clock(int link_rate,
+					    int lane_num,
+					    int bpp)
+{
+	return (link_rate * lane_num * 8) / bpp;
+}
+
+/***** amdgpu specific DP functions *****/
+
+/* First get the min lane# when low rate is used according to pixel clock
+ * (prefer low rate), second check max lane# supported by DP panel,
+ * if the max lane# < low rate lane# then use max lane# instead.
+ */
+static int amdgpu_atombios_dp_get_dp_lane_number(struct drm_connector *connector,
+					  u8 dpcd[DP_DPCD_SIZE],
+					  int pix_clock)
+{
+	int bpp = amdgpu_atombios_dp_convert_bpc_to_bpp(amdgpu_connector_get_monitor_bpc(connector));
+	int max_link_rate = drm_dp_max_link_rate(dpcd);
+	int max_lane_num = drm_dp_max_lane_count(dpcd);
+	int lane_num;
+	int max_dp_pix_clock;
+
+	for (lane_num = 1; lane_num < max_lane_num; lane_num <<= 1) {
+		max_dp_pix_clock = amdgpu_atombios_dp_get_max_dp_pix_clock(max_link_rate, lane_num, bpp);
+		if (pix_clock <= max_dp_pix_clock)
+			break;
+	}
+
+	return lane_num;
+}
+
+static int amdgpu_atombios_dp_get_dp_link_clock(struct drm_connector *connector,
+					 u8 dpcd[DP_DPCD_SIZE],
+					 int pix_clock)
+{
+	int bpp = amdgpu_atombios_dp_convert_bpc_to_bpp(amdgpu_connector_get_monitor_bpc(connector));
+	int lane_num, max_pix_clock;
+
+	if (amdgpu_connector_encoder_get_dp_bridge_encoder_id(connector) ==
+	    ENCODER_OBJECT_ID_NUTMEG)
+		return 270000;
+
+	lane_num = amdgpu_atombios_dp_get_dp_lane_number(connector, dpcd, pix_clock);
+	max_pix_clock = amdgpu_atombios_dp_get_max_dp_pix_clock(162000, lane_num, bpp);
+	if (pix_clock <= max_pix_clock)
+		return 162000;
+	max_pix_clock = amdgpu_atombios_dp_get_max_dp_pix_clock(270000, lane_num, bpp);
+	if (pix_clock <= max_pix_clock)
+		return 270000;
+	if (amdgpu_connector_is_dp12_capable(connector)) {
+		max_pix_clock = amdgpu_atombios_dp_get_max_dp_pix_clock(540000, lane_num, bpp);
+		if (pix_clock <= max_pix_clock)
+			return 540000;
+	}
+
+	return drm_dp_max_link_rate(dpcd);
+}
+
+static u8 amdgpu_atombios_dp_encoder_service(struct amdgpu_device *adev,
+				      int action, int dp_clock,
+				      u8 ucconfig, u8 lane_num)
+{
+	DP_ENCODER_SERVICE_PARAMETERS args;
+	int index = GetIndexIntoMasterTable(COMMAND, DPEncoderService);
+
+	memset(&args, 0, sizeof(args));
+	args.ucLinkClock = dp_clock / 10;
+	args.ucConfig = ucconfig;
+	args.ucAction = action;
+	args.ucLaneNum = lane_num;
+	args.ucStatus = 0;
+
+	amdgpu_atom_execute_table(adev->mode_info.atom_context, index, (uint32_t *)&args);
+	return args.ucStatus;
+}
+
+u8 amdgpu_atombios_dp_get_sinktype(struct amdgpu_connector *amdgpu_connector)
+{
+	struct drm_device *dev = amdgpu_connector->base.dev;
+	struct amdgpu_device *adev = dev->dev_private;
+
+	return amdgpu_atombios_dp_encoder_service(adev, ATOM_DP_ACTION_GET_SINK_TYPE, 0,
+					   amdgpu_connector->ddc_bus->rec.i2c_id, 0);
+}
+
+static void amdgpu_atombios_dp_probe_oui(struct amdgpu_connector *amdgpu_connector)
+{
+	struct amdgpu_connector_atom_dig *dig_connector = amdgpu_connector->con_priv;
+	u8 buf[3];
+
+	if (!(dig_connector->dpcd[DP_DOWN_STREAM_PORT_COUNT] & DP_OUI_SUPPORT))
+		return;
+
+	if (drm_dp_dpcd_read(&amdgpu_connector->ddc_bus->aux, DP_SINK_OUI, buf, 3) == 3)
+		DRM_DEBUG_KMS("Sink OUI: %02hx%02hx%02hx\n",
+			      buf[0], buf[1], buf[2]);
+
+	if (drm_dp_dpcd_read(&amdgpu_connector->ddc_bus->aux, DP_BRANCH_OUI, buf, 3) == 3)
+		DRM_DEBUG_KMS("Branch OUI: %02hx%02hx%02hx\n",
+			      buf[0], buf[1], buf[2]);
+}
+
+int amdgpu_atombios_dp_get_dpcd(struct amdgpu_connector *amdgpu_connector)
+{
+	struct amdgpu_connector_atom_dig *dig_connector = amdgpu_connector->con_priv;
+	u8 msg[DP_DPCD_SIZE];
+	int ret, i;
+
+	ret = drm_dp_dpcd_read(&amdgpu_connector->ddc_bus->aux, DP_DPCD_REV, msg,
+			       DP_DPCD_SIZE);
+	if (ret > 0) {
+		memcpy(dig_connector->dpcd, msg, DP_DPCD_SIZE);
+		DRM_DEBUG_KMS("DPCD: ");
+		for (i = 0; i < DP_DPCD_SIZE; i++)
+			DRM_DEBUG_KMS("%02x ", msg[i]);
+		DRM_DEBUG_KMS("\n");
+
+		amdgpu_atombios_dp_probe_oui(amdgpu_connector);
+
+		return 0;
+	}
+	dig_connector->dpcd[0] = 0;
+	return -EINVAL;
+}
+
+int amdgpu_atombios_dp_get_panel_mode(struct drm_encoder *encoder,
+			       struct drm_connector *connector)
+{
+	struct amdgpu_connector *amdgpu_connector = to_amdgpu_connector(connector);
+	struct amdgpu_connector_atom_dig *dig_connector;
+	int panel_mode = DP_PANEL_MODE_EXTERNAL_DP_MODE;
+	u16 dp_bridge = amdgpu_connector_encoder_get_dp_bridge_encoder_id(connector);
+	u8 tmp;
+
+	if (!amdgpu_connector->con_priv)
+		return panel_mode;
+
+	dig_connector = amdgpu_connector->con_priv;
+
+	if (dp_bridge != ENCODER_OBJECT_ID_NONE) {
+		/* DP bridge chips */
+		if (drm_dp_dpcd_readb(&amdgpu_connector->ddc_bus->aux,
+				      DP_EDP_CONFIGURATION_CAP, &tmp) == 1) {
+			if (tmp & 1)
+				panel_mode = DP_PANEL_MODE_INTERNAL_DP2_MODE;
+			else if ((dp_bridge == ENCODER_OBJECT_ID_NUTMEG) ||
+				 (dp_bridge == ENCODER_OBJECT_ID_TRAVIS))
+				panel_mode = DP_PANEL_MODE_INTERNAL_DP1_MODE;
+			else
+				panel_mode = DP_PANEL_MODE_EXTERNAL_DP_MODE;
+		}
+	} else if (connector->connector_type == DRM_MODE_CONNECTOR_eDP) {
+		/* eDP */
+		if (drm_dp_dpcd_readb(&amdgpu_connector->ddc_bus->aux,
+				      DP_EDP_CONFIGURATION_CAP, &tmp) == 1) {
+			if (tmp & 1)
+				panel_mode = DP_PANEL_MODE_INTERNAL_DP2_MODE;
+		}
+	}
+
+	return panel_mode;
+}
+
+void amdgpu_atombios_dp_set_link_config(struct drm_connector *connector,
+				 const struct drm_display_mode *mode)
+{
+	struct amdgpu_connector *amdgpu_connector = to_amdgpu_connector(connector);
+	struct amdgpu_connector_atom_dig *dig_connector;
+
+	if (!amdgpu_connector->con_priv)
+		return;
+	dig_connector = amdgpu_connector->con_priv;
+
+	if ((dig_connector->dp_sink_type == CONNECTOR_OBJECT_ID_DISPLAYPORT) ||
+	    (dig_connector->dp_sink_type == CONNECTOR_OBJECT_ID_eDP)) {
+		dig_connector->dp_clock =
+			amdgpu_atombios_dp_get_dp_link_clock(connector, dig_connector->dpcd, mode->clock);
+		dig_connector->dp_lane_count =
+			amdgpu_atombios_dp_get_dp_lane_number(connector, dig_connector->dpcd, mode->clock);
+	}
+}
+
+int amdgpu_atombios_dp_mode_valid_helper(struct drm_connector *connector,
+				  struct drm_display_mode *mode)
+{
+	struct amdgpu_connector *amdgpu_connector = to_amdgpu_connector(connector);
+	struct amdgpu_connector_atom_dig *dig_connector;
+	int dp_clock;
+
+	if (!amdgpu_connector->con_priv)
+		return MODE_CLOCK_HIGH;
+	dig_connector = amdgpu_connector->con_priv;
+
+	dp_clock =
+		amdgpu_atombios_dp_get_dp_link_clock(connector, dig_connector->dpcd, mode->clock);
+
+	if ((dp_clock == 540000) &&
+	    (!amdgpu_connector_is_dp12_capable(connector)))
+		return MODE_CLOCK_HIGH;
+
+	return MODE_OK;
+}
+
+bool amdgpu_atombios_dp_needs_link_train(struct amdgpu_connector *amdgpu_connector)
+{
+	u8 link_status[DP_LINK_STATUS_SIZE];
+	struct amdgpu_connector_atom_dig *dig = amdgpu_connector->con_priv;
+
+	if (drm_dp_dpcd_read_link_status(&amdgpu_connector->ddc_bus->aux, link_status)
+	    <= 0)
+		return false;
+	if (drm_dp_channel_eq_ok(link_status, dig->dp_lane_count))
+		return false;
+	return true;
+}
+
+void amdgpu_atombios_dp_set_rx_power_state(struct drm_connector *connector,
+				    u8 power_state)
+{
+	struct amdgpu_connector *amdgpu_connector = to_amdgpu_connector(connector);
+	struct amdgpu_connector_atom_dig *dig_connector;
+
+	if (!amdgpu_connector->con_priv)
+		return;
+
+	dig_connector = amdgpu_connector->con_priv;
+
+	/* power up/down the sink */
+	if (dig_connector->dpcd[0] >= 0x11) {
+		drm_dp_dpcd_writeb(&amdgpu_connector->ddc_bus->aux,
+				   DP_SET_POWER, power_state);
+		usleep_range(1000, 2000);
+	}
+}
+
+struct amdgpu_atombios_dp_link_train_info {
+	struct amdgpu_device *adev;
+	struct drm_encoder *encoder;
+	struct drm_connector *connector;
+	int dp_clock;
+	int dp_lane_count;
+	bool tp3_supported;
+	u8 dpcd[DP_RECEIVER_CAP_SIZE];
+	u8 train_set[4];
+	u8 link_status[DP_LINK_STATUS_SIZE];
+	u8 tries;
+	struct drm_dp_aux *aux;
+};
+
+static void
+amdgpu_atombios_dp_update_vs_emph(struct amdgpu_atombios_dp_link_train_info *dp_info)
+{
+	/* set the initial vs/emph on the source */
+	amdgpu_atombios_encoder_setup_dig_transmitter(dp_info->encoder,
+					       ATOM_TRANSMITTER_ACTION_SETUP_VSEMPH,
+					       0, dp_info->train_set[0]); /* sets all lanes at once */
+
+	/* set the vs/emph on the sink */
+	drm_dp_dpcd_write(dp_info->aux, DP_TRAINING_LANE0_SET,
+			  dp_info->train_set, dp_info->dp_lane_count);
+}
+
+static void
+amdgpu_atombios_dp_set_tp(struct amdgpu_atombios_dp_link_train_info *dp_info, int tp)
+{
+	int rtp = 0;
+
+	/* set training pattern on the source */
+	switch (tp) {
+	case DP_TRAINING_PATTERN_1:
+		rtp = ATOM_ENCODER_CMD_DP_LINK_TRAINING_PATTERN1;
+		break;
+	case DP_TRAINING_PATTERN_2:
+		rtp = ATOM_ENCODER_CMD_DP_LINK_TRAINING_PATTERN2;
+		break;
+	case DP_TRAINING_PATTERN_3:
+		rtp = ATOM_ENCODER_CMD_DP_LINK_TRAINING_PATTERN3;
+			break;
+	}
+	amdgpu_atombios_encoder_setup_dig_encoder(dp_info->encoder, rtp, 0);
+
+	/* enable training pattern on the sink */
+	drm_dp_dpcd_writeb(dp_info->aux, DP_TRAINING_PATTERN_SET, tp);
+}
+
+static int
+amdgpu_atombios_dp_link_train_init(struct amdgpu_atombios_dp_link_train_info *dp_info)
+{
+	struct amdgpu_encoder *amdgpu_encoder = to_amdgpu_encoder(dp_info->encoder);
+	struct amdgpu_encoder_atom_dig *dig = amdgpu_encoder->enc_priv;
+	u8 tmp;
+
+	/* power up the sink */
+	amdgpu_atombios_dp_set_rx_power_state(dp_info->connector, DP_SET_POWER_D0);
+
+	/* possibly enable downspread on the sink */
+	if (dp_info->dpcd[3] & 0x1)
+		drm_dp_dpcd_writeb(dp_info->aux,
+				   DP_DOWNSPREAD_CTRL, DP_SPREAD_AMP_0_5);
+	else
+		drm_dp_dpcd_writeb(dp_info->aux,
+				   DP_DOWNSPREAD_CTRL, 0);
+
+	if (dig->panel_mode == DP_PANEL_MODE_INTERNAL_DP2_MODE)
+		drm_dp_dpcd_writeb(dp_info->aux, DP_EDP_CONFIGURATION_SET, 1);
+
+	/* set the lane count on the sink */
+	tmp = dp_info->dp_lane_count;
+	if (drm_dp_enhanced_frame_cap(dp_info->dpcd))
+		tmp |= DP_LANE_COUNT_ENHANCED_FRAME_EN;
+	drm_dp_dpcd_writeb(dp_info->aux, DP_LANE_COUNT_SET, tmp);
+
+	/* set the link rate on the sink */
+	tmp = drm_dp_link_rate_to_bw_code(dp_info->dp_clock);
+	drm_dp_dpcd_writeb(dp_info->aux, DP_LINK_BW_SET, tmp);
+
+	/* start training on the source */
+	amdgpu_atombios_encoder_setup_dig_encoder(dp_info->encoder,
+					   ATOM_ENCODER_CMD_DP_LINK_TRAINING_START, 0);
+
+	/* disable the training pattern on the sink */
+	drm_dp_dpcd_writeb(dp_info->aux,
+			   DP_TRAINING_PATTERN_SET,
+			   DP_TRAINING_PATTERN_DISABLE);
+
+	return 0;
+}
+
+static int
+amdgpu_atombios_dp_link_train_finish(struct amdgpu_atombios_dp_link_train_info *dp_info)
+{
+	udelay(400);
+
+	/* disable the training pattern on the sink */
+	drm_dp_dpcd_writeb(dp_info->aux,
+			   DP_TRAINING_PATTERN_SET,
+			   DP_TRAINING_PATTERN_DISABLE);
+
+	/* disable the training pattern on the source */
+	amdgpu_atombios_encoder_setup_dig_encoder(dp_info->encoder,
+					   ATOM_ENCODER_CMD_DP_LINK_TRAINING_COMPLETE, 0);
+
+	return 0;
+}
+
+static int
+amdgpu_atombios_dp_link_train_cr(struct amdgpu_atombios_dp_link_train_info *dp_info)
+{
+	bool clock_recovery;
+	u8 voltage;
+	int i;
+
+	amdgpu_atombios_dp_set_tp(dp_info, DP_TRAINING_PATTERN_1);
+	memset(dp_info->train_set, 0, 4);
+	amdgpu_atombios_dp_update_vs_emph(dp_info);
+
+	udelay(400);
+
+	/* clock recovery loop */
+	clock_recovery = false;
+	dp_info->tries = 0;
+	voltage = 0xff;
+	while (1) {
+		drm_dp_link_train_clock_recovery_delay(dp_info->dpcd);
+
+		if (drm_dp_dpcd_read_link_status(dp_info->aux,
+						 dp_info->link_status) <= 0) {
+			DRM_ERROR("displayport link status failed\n");
+			break;
+		}
+
+		if (drm_dp_clock_recovery_ok(dp_info->link_status, dp_info->dp_lane_count)) {
+			clock_recovery = true;
+			break;
+		}
+
+		for (i = 0; i < dp_info->dp_lane_count; i++) {
+			if ((dp_info->train_set[i] & DP_TRAIN_MAX_SWING_REACHED) == 0)
+				break;
+		}
+		if (i == dp_info->dp_lane_count) {
+			DRM_ERROR("clock recovery reached max voltage\n");
+			break;
+		}
+
+		if ((dp_info->train_set[0] & DP_TRAIN_VOLTAGE_SWING_MASK) == voltage) {
+			++dp_info->tries;
+			if (dp_info->tries == 5) {
+				DRM_ERROR("clock recovery tried 5 times\n");
+				break;
+			}
+		} else
+			dp_info->tries = 0;
+
+		voltage = dp_info->train_set[0] & DP_TRAIN_VOLTAGE_SWING_MASK;
+
+		/* Compute new train_set as requested by sink */
+		amdgpu_atombios_dp_get_adjust_train(dp_info->link_status, dp_info->dp_lane_count,
+					     dp_info->train_set);
+
+		amdgpu_atombios_dp_update_vs_emph(dp_info);
+	}
+	if (!clock_recovery) {
+		DRM_ERROR("clock recovery failed\n");
+		return -1;
+	} else {
+		DRM_DEBUG_KMS("clock recovery at voltage %d pre-emphasis %d\n",
+			  dp_info->train_set[0] & DP_TRAIN_VOLTAGE_SWING_MASK,
+			  (dp_info->train_set[0] & DP_TRAIN_PRE_EMPHASIS_MASK) >>
+			  DP_TRAIN_PRE_EMPHASIS_SHIFT);
+		return 0;
+	}
+}
+
+static int
+amdgpu_atombios_dp_link_train_ce(struct amdgpu_atombios_dp_link_train_info *dp_info)
+{
+	bool channel_eq;
+
+	if (dp_info->tp3_supported)
+		amdgpu_atombios_dp_set_tp(dp_info, DP_TRAINING_PATTERN_3);
+	else
+		amdgpu_atombios_dp_set_tp(dp_info, DP_TRAINING_PATTERN_2);
+
+	/* channel equalization loop */
+	dp_info->tries = 0;
+	channel_eq = false;
+	while (1) {
+		drm_dp_link_train_channel_eq_delay(dp_info->dpcd);
+
+		if (drm_dp_dpcd_read_link_status(dp_info->aux,
+						 dp_info->link_status) <= 0) {
+			DRM_ERROR("displayport link status failed\n");
+			break;
+		}
+
+		if (drm_dp_channel_eq_ok(dp_info->link_status, dp_info->dp_lane_count)) {
+			channel_eq = true;
+			break;
+		}
+
+		/* Try 5 times */
+		if (dp_info->tries > 5) {
+			DRM_ERROR("channel eq failed: 5 tries\n");
+			break;
+		}
+
+		/* Compute new train_set as requested by sink */
+		amdgpu_atombios_dp_get_adjust_train(dp_info->link_status, dp_info->dp_lane_count,
+					     dp_info->train_set);
+
+		amdgpu_atombios_dp_update_vs_emph(dp_info);
+		dp_info->tries++;
+	}
+
+	if (!channel_eq) {
+		DRM_ERROR("channel eq failed\n");
+		return -1;
+	} else {
+		DRM_DEBUG_KMS("channel eq at voltage %d pre-emphasis %d\n",
+			  dp_info->train_set[0] & DP_TRAIN_VOLTAGE_SWING_MASK,
+			  (dp_info->train_set[0] & DP_TRAIN_PRE_EMPHASIS_MASK)
+			  >> DP_TRAIN_PRE_EMPHASIS_SHIFT);
+		return 0;
+	}
+}
+
+void amdgpu_atombios_dp_link_train(struct drm_encoder *encoder,
+			    struct drm_connector *connector)
+{
+	struct drm_device *dev = encoder->dev;
+	struct amdgpu_device *adev = dev->dev_private;
+	struct amdgpu_encoder *amdgpu_encoder = to_amdgpu_encoder(encoder);
+	struct amdgpu_encoder_atom_dig *dig;
+	struct amdgpu_connector *amdgpu_connector;
+	struct amdgpu_connector_atom_dig *dig_connector;
+	struct amdgpu_atombios_dp_link_train_info dp_info;
+	u8 tmp;
+
+	if (!amdgpu_encoder->enc_priv)
+		return;
+	dig = amdgpu_encoder->enc_priv;
+
+	amdgpu_connector = to_amdgpu_connector(connector);
+	if (!amdgpu_connector->con_priv)
+		return;
+	dig_connector = amdgpu_connector->con_priv;
+
+	if ((dig_connector->dp_sink_type != CONNECTOR_OBJECT_ID_DISPLAYPORT) &&
+	    (dig_connector->dp_sink_type != CONNECTOR_OBJECT_ID_eDP))
+		return;
+
+	if (drm_dp_dpcd_readb(&amdgpu_connector->ddc_bus->aux, DP_MAX_LANE_COUNT, &tmp)
+	    == 1) {
+		if (tmp & DP_TPS3_SUPPORTED)
+			dp_info.tp3_supported = true;
+		else
+			dp_info.tp3_supported = false;
+	} else {
+		dp_info.tp3_supported = false;
+	}
+
+	memcpy(dp_info.dpcd, dig_connector->dpcd, DP_RECEIVER_CAP_SIZE);
+	dp_info.adev = adev;
+	dp_info.encoder = encoder;
+	dp_info.connector = connector;
+	dp_info.dp_lane_count = dig_connector->dp_lane_count;
+	dp_info.dp_clock = dig_connector->dp_clock;
+	dp_info.aux = &amdgpu_connector->ddc_bus->aux;
+
+	if (amdgpu_atombios_dp_link_train_init(&dp_info))
+		goto done;
+	if (amdgpu_atombios_dp_link_train_cr(&dp_info))
+		goto done;
+	if (amdgpu_atombios_dp_link_train_ce(&dp_info))
+		goto done;
+done:
+	if (amdgpu_atombios_dp_link_train_finish(&dp_info))
+		return;
+}