drivers/gpu/drm/i915/intel_dp_mst.c - kernel/msm-4.19 - Gitiles

 /*
  * Copyright © 2008 Intel Corporation
  *             2014 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 (including the next
  * paragraph) 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 AUTHORS OR COPYRIGHT HOLDERS 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.
  *
  */

 #include <drm/drmP.h>
 #include "i915_drv.h"
 #include "intel_drv.h"
 #include <drm/drm_atomic_helper.h>
 #include <drm/drm_crtc_helper.h>
 #include <drm/drm_edid.h>

 static bool intel_dp_mst_compute_config(struct intel_encoder *encoder,
 					struct intel_crtc_state *pipe_config)
 {
 	struct intel_dp_mst_encoder *intel_mst = enc_to_mst(&encoder->base);
 	struct intel_digital_port *intel_dig_port = intel_mst->primary;
 	struct intel_dp *intel_dp = &intel_dig_port->dp;
 	struct drm_atomic_state *state;
 	int bpp, i;
 	int lane_count, slots;
 	const struct drm_display_mode *adjusted_mode = &pipe_config->base.adjusted_mode;
 	struct drm_connector *drm_connector;
 	struct intel_connector *connector, *found = NULL;
 	struct drm_connector_state *connector_state;
 	int mst_pbn;

 	pipe_config->dp_encoder_is_mst = true;
 	pipe_config->has_pch_encoder = false;
 	pipe_config->has_dp_encoder = true;
 	bpp = 24;
 	/*
 	 * for MST we always configure max link bw - the spec doesn't
 	 * seem to suggest we should do otherwise.
 	 */
 	lane_count = drm_dp_max_lane_count(intel_dp->dpcd);


 	pipe_config->lane_count = lane_count;

 	pipe_config->pipe_bpp = 24;
 	pipe_config->port_clock = intel_dp_max_link_rate(intel_dp);

 	state = pipe_config->base.state;

 	for_each_connector_in_state(state, drm_connector, connector_state, i) {
 		connector = to_intel_connector(drm_connector);

 		if (connector_state->best_encoder == &encoder->base) {
 			found = connector;
 			break;
 		}
 	}

 	if (!found) {
 		DRM_ERROR("can't find connector\n");
 		return false;
 	}

 	mst_pbn = drm_dp_calc_pbn_mode(adjusted_mode->crtc_clock, bpp);

 	pipe_config->pbn = mst_pbn;
 	slots = drm_dp_find_vcpi_slots(&intel_dp->mst_mgr, mst_pbn);

 	intel_link_compute_m_n(bpp, lane_count,
 			       adjusted_mode->crtc_clock,
 			       pipe_config->port_clock,
 			       &pipe_config->dp_m_n);

 	pipe_config->dp_m_n.tu = slots;

 	return true;

 }

 static void intel_mst_disable_dp(struct intel_encoder *encoder)
 {
 	struct intel_dp_mst_encoder *intel_mst = enc_to_mst(&encoder->base);
 	struct intel_digital_port *intel_dig_port = intel_mst->primary;
 	struct intel_dp *intel_dp = &intel_dig_port->dp;
 	int ret;

 	DRM_DEBUG_KMS("%d\n", intel_dp->active_mst_links);

 	drm_dp_mst_reset_vcpi_slots(&intel_dp->mst_mgr, intel_mst->connector->port);

 	ret = drm_dp_update_payload_part1(&intel_dp->mst_mgr);
 	if (ret) {
 		DRM_ERROR("failed to update payload %d\n", ret);
 	}
 }

 static void intel_mst_post_disable_dp(struct intel_encoder *encoder)
 {
 	struct intel_dp_mst_encoder *intel_mst = enc_to_mst(&encoder->base);
 	struct intel_digital_port *intel_dig_port = intel_mst->primary;
 	struct intel_dp *intel_dp = &intel_dig_port->dp;

 	DRM_DEBUG_KMS("%d\n", intel_dp->active_mst_links);

 	/* this can fail */
 	drm_dp_check_act_status(&intel_dp->mst_mgr);
 	/* and this can also fail */
 	drm_dp_update_payload_part2(&intel_dp->mst_mgr);

 	drm_dp_mst_deallocate_vcpi(&intel_dp->mst_mgr, intel_mst->connector->port);

 	intel_dp->active_mst_links--;

 	intel_mst->connector = NULL;
 	if (intel_dp->active_mst_links == 0) {
 		intel_dig_port->base.post_disable(&intel_dig_port->base);
 		intel_dp_sink_dpms(intel_dp, DRM_MODE_DPMS_OFF);
 	}
 }

 static void intel_mst_pre_enable_dp(struct intel_encoder *encoder)
 {
 	struct intel_dp_mst_encoder *intel_mst = enc_to_mst(&encoder->base);
 	struct intel_digital_port *intel_dig_port = intel_mst->primary;
 	struct intel_dp *intel_dp = &intel_dig_port->dp;
 	struct drm_device *dev = encoder->base.dev;
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	enum port port = intel_dig_port->port;
 	int ret;
 	uint32_t temp;
 	struct intel_connector *found = NULL, *connector;
 	int slots;
 	struct drm_crtc *crtc = encoder->base.crtc;
 	struct intel_crtc *intel_crtc = to_intel_crtc(crtc);

 	for_each_intel_connector(dev, connector) {
 		if (connector->base.state->best_encoder == &encoder->base) {
 			found = connector;
 			break;
 		}
 	}

 	if (!found) {
 		DRM_ERROR("can't find connector\n");
 		return;
 	}

 	/* MST encoders are bound to a crtc, not to a connector,
 	 * force the mapping here for get_hw_state.
 	 */
 	found->encoder = encoder;

 	DRM_DEBUG_KMS("%d\n", intel_dp->active_mst_links);

 	intel_mst->connector = found;

 	if (intel_dp->active_mst_links == 0) {
 		intel_prepare_ddi_buffer(&intel_dig_port->base);

 		intel_ddi_clk_select(&intel_dig_port->base, intel_crtc->config);

 		intel_dp_set_link_params(intel_dp, intel_crtc->config);

 		intel_ddi_init_dp_buf_reg(&intel_dig_port->base);

 		intel_dp_sink_dpms(intel_dp, DRM_MODE_DPMS_ON);

 		intel_dp_start_link_train(intel_dp);
 		intel_dp_stop_link_train(intel_dp);
 	}

 	ret = drm_dp_mst_allocate_vcpi(&intel_dp->mst_mgr,
 				       intel_mst->connector->port,
 				       intel_crtc->config->pbn, &slots);
 	if (ret == false) {
 		DRM_ERROR("failed to allocate vcpi\n");
 		return;
 	}


 	intel_dp->active_mst_links++;
 	temp = I915_READ(DP_TP_STATUS(port));
 	I915_WRITE(DP_TP_STATUS(port), temp);

 	ret = drm_dp_update_payload_part1(&intel_dp->mst_mgr);
 }

 static void intel_mst_enable_dp(struct intel_encoder *encoder)
 {
 	struct intel_dp_mst_encoder *intel_mst = enc_to_mst(&encoder->base);
 	struct intel_digital_port *intel_dig_port = intel_mst->primary;
 	struct intel_dp *intel_dp = &intel_dig_port->dp;
 	struct drm_device *dev = intel_dig_port->base.base.dev;
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	enum port port = intel_dig_port->port;
 	int ret;

 	DRM_DEBUG_KMS("%d\n", intel_dp->active_mst_links);

 	if (wait_for((I915_READ(DP_TP_STATUS(port)) & DP_TP_STATUS_ACT_SENT),
 		     1))
 		DRM_ERROR("Timed out waiting for ACT sent\n");

 	ret = drm_dp_check_act_status(&intel_dp->mst_mgr);

 	ret = drm_dp_update_payload_part2(&intel_dp->mst_mgr);
 }

 static bool intel_dp_mst_enc_get_hw_state(struct intel_encoder *encoder,
 				      enum pipe *pipe)
 {
 	struct intel_dp_mst_encoder *intel_mst = enc_to_mst(&encoder->base);
 	*pipe = intel_mst->pipe;
 	if (intel_mst->connector)
 		return true;
 	return false;
 }

 static void intel_dp_mst_enc_get_config(struct intel_encoder *encoder,
 					struct intel_crtc_state *pipe_config)
 {
 	struct intel_dp_mst_encoder *intel_mst = enc_to_mst(&encoder->base);
 	struct intel_digital_port *intel_dig_port = intel_mst->primary;
 	struct intel_crtc *crtc = to_intel_crtc(encoder->base.crtc);
 	struct drm_device *dev = encoder->base.dev;
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	enum transcoder cpu_transcoder = pipe_config->cpu_transcoder;
 	u32 temp, flags = 0;

 	pipe_config->has_dp_encoder = true;

 	temp = I915_READ(TRANS_DDI_FUNC_CTL(cpu_transcoder));
 	if (temp & TRANS_DDI_PHSYNC)
 		flags |= DRM_MODE_FLAG_PHSYNC;
 	else
 		flags |= DRM_MODE_FLAG_NHSYNC;
 	if (temp & TRANS_DDI_PVSYNC)
 		flags |= DRM_MODE_FLAG_PVSYNC;
 	else
 		flags |= DRM_MODE_FLAG_NVSYNC;

 	switch (temp & TRANS_DDI_BPC_MASK) {
 	case TRANS_DDI_BPC_6:
 		pipe_config->pipe_bpp = 18;
 		break;
 	case TRANS_DDI_BPC_8:
 		pipe_config->pipe_bpp = 24;
 		break;
 	case TRANS_DDI_BPC_10:
 		pipe_config->pipe_bpp = 30;
 		break;
 	case TRANS_DDI_BPC_12:
 		pipe_config->pipe_bpp = 36;
 		break;
 	default:
 		break;
 	}
 	pipe_config->base.adjusted_mode.flags |= flags;

 	pipe_config->lane_count =
 		((temp & DDI_PORT_WIDTH_MASK) >> DDI_PORT_WIDTH_SHIFT) + 1;

 	intel_dp_get_m_n(crtc, pipe_config);

 	intel_ddi_clock_get(&intel_dig_port->base, pipe_config);
 }

 static int intel_dp_mst_get_ddc_modes(struct drm_connector *connector)
 {
 	struct intel_connector *intel_connector = to_intel_connector(connector);
 	struct intel_dp *intel_dp = intel_connector->mst_port;
 	struct edid *edid;
 	int ret;

 	if (!intel_dp) {
 		return intel_connector_update_modes(connector, NULL);
 	}

 	edid = drm_dp_mst_get_edid(connector, &intel_dp->mst_mgr, intel_connector->port);
 	ret = intel_connector_update_modes(connector, edid);
 	kfree(edid);

 	return ret;
 }

 static enum drm_connector_status
 intel_dp_mst_detect(struct drm_connector *connector, bool force)
 {
 	struct intel_connector *intel_connector = to_intel_connector(connector);
 	struct intel_dp *intel_dp = intel_connector->mst_port;

 	if (!intel_dp)
 		return connector_status_disconnected;
 	return drm_dp_mst_detect_port(connector, &intel_dp->mst_mgr, intel_connector->port);
 }

 static int
 intel_dp_mst_set_property(struct drm_connector *connector,
 			  struct drm_property *property,
 			  uint64_t val)
 {
 	return 0;
 }

 static void
 intel_dp_mst_connector_destroy(struct drm_connector *connector)
 {
 	struct intel_connector *intel_connector = to_intel_connector(connector);

 	if (!IS_ERR_OR_NULL(intel_connector->edid))
 		kfree(intel_connector->edid);

 	drm_connector_cleanup(connector);
 	kfree(connector);
 }

 static const struct drm_connector_funcs intel_dp_mst_connector_funcs = {
 	.dpms = drm_atomic_helper_connector_dpms,
 	.detect = intel_dp_mst_detect,
 	.fill_modes = drm_helper_probe_single_connector_modes,
 	.set_property = intel_dp_mst_set_property,
 	.atomic_get_property = intel_connector_atomic_get_property,
 	.early_unregister = intel_connector_unregister,
 	.destroy = intel_dp_mst_connector_destroy,
 	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
 	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
 };

 static int intel_dp_mst_get_modes(struct drm_connector *connector)
 {
 	return intel_dp_mst_get_ddc_modes(connector);
 }

 static enum drm_mode_status
 intel_dp_mst_mode_valid(struct drm_connector *connector,
 			struct drm_display_mode *mode)
 {
 	int max_dotclk = to_i915(connector->dev)->max_dotclk_freq;

 	/* TODO - validate mode against available PBN for link */
 	if (mode->clock < 10000)
 		return MODE_CLOCK_LOW;

 	if (mode->flags & DRM_MODE_FLAG_DBLCLK)
 		return MODE_H_ILLEGAL;

 	if (mode->clock > max_dotclk)
 		return MODE_CLOCK_HIGH;

 	return MODE_OK;
 }

 static struct drm_encoder *intel_mst_atomic_best_encoder(struct drm_connector *connector,
 							 struct drm_connector_state *state)
 {
 	struct intel_connector *intel_connector = to_intel_connector(connector);
 	struct intel_dp *intel_dp = intel_connector->mst_port;
 	struct intel_crtc *crtc = to_intel_crtc(state->crtc);

 	if (!intel_dp)
 		return NULL;
 	return &intel_dp->mst_encoders[crtc->pipe]->base.base;
 }

 static struct drm_encoder *intel_mst_best_encoder(struct drm_connector *connector)
 {
 	struct intel_connector *intel_connector = to_intel_connector(connector);
 	struct intel_dp *intel_dp = intel_connector->mst_port;
 	if (!intel_dp)
 		return NULL;
 	return &intel_dp->mst_encoders[0]->base.base;
 }

 static const struct drm_connector_helper_funcs intel_dp_mst_connector_helper_funcs = {
 	.get_modes = intel_dp_mst_get_modes,
 	.mode_valid = intel_dp_mst_mode_valid,
 	.atomic_best_encoder = intel_mst_atomic_best_encoder,
 	.best_encoder = intel_mst_best_encoder,
 };

 static void intel_dp_mst_encoder_destroy(struct drm_encoder *encoder)
 {
 	struct intel_dp_mst_encoder *intel_mst = enc_to_mst(encoder);

 	drm_encoder_cleanup(encoder);
 	kfree(intel_mst);
 }

 static const struct drm_encoder_funcs intel_dp_mst_enc_funcs = {
 	.destroy = intel_dp_mst_encoder_destroy,
 };

 static bool intel_dp_mst_get_hw_state(struct intel_connector *connector)
 {
 	if (connector->encoder && connector->base.state->crtc) {
 		enum pipe pipe;
 		if (!connector->encoder->get_hw_state(connector->encoder, &pipe))
 			return false;
 		return true;
 	}
 	return false;
 }

 static void intel_connector_add_to_fbdev(struct intel_connector *connector)
 {
 #ifdef CONFIG_DRM_FBDEV_EMULATION
 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);

 	if (dev_priv->fbdev)
 		drm_fb_helper_add_one_connector(&dev_priv->fbdev->helper,
 						&connector->base);
 #endif
 }

 static void intel_connector_remove_from_fbdev(struct intel_connector *connector)
 {
 #ifdef CONFIG_DRM_FBDEV_EMULATION
 	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);

 	if (dev_priv->fbdev)
 		drm_fb_helper_remove_one_connector(&dev_priv->fbdev->helper,
 						   &connector->base);
 #endif
 }

 static struct drm_connector *intel_dp_add_mst_connector(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port, const char *pathprop)
 {
 	struct intel_dp *intel_dp = container_of(mgr, struct intel_dp, mst_mgr);
 	struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
 	struct drm_device *dev = intel_dig_port->base.base.dev;
 	struct intel_connector *intel_connector;
 	struct drm_connector *connector;
 	int i;

 	intel_connector = intel_connector_alloc();
 	if (!intel_connector)
 		return NULL;

 	connector = &intel_connector->base;
 	drm_connector_init(dev, connector, &intel_dp_mst_connector_funcs, DRM_MODE_CONNECTOR_DisplayPort);
 	drm_connector_helper_add(connector, &intel_dp_mst_connector_helper_funcs);

 	intel_connector->get_hw_state = intel_dp_mst_get_hw_state;
 	intel_connector->mst_port = intel_dp;
 	intel_connector->port = port;

 	for (i = PIPE_A; i <= PIPE_C; i++) {
 		drm_mode_connector_attach_encoder(&intel_connector->base,
 						  &intel_dp->mst_encoders[i]->base.base);
 	}
 	intel_dp_add_properties(intel_dp, connector);

 	drm_object_attach_property(&connector->base, dev->mode_config.path_property, 0);
 	drm_object_attach_property(&connector->base, dev->mode_config.tile_property, 0);

 	drm_mode_connector_set_path_property(connector, pathprop);
 	return connector;
 }

 static void intel_dp_register_mst_connector(struct drm_connector *connector)
 {
 	struct intel_connector *intel_connector = to_intel_connector(connector);
 	struct drm_device *dev = connector->dev;
 	drm_modeset_lock_all(dev);
 	intel_connector_add_to_fbdev(intel_connector);
 	drm_modeset_unlock_all(dev);
 	drm_connector_register(&intel_connector->base);
 }

 static void intel_dp_destroy_mst_connector(struct drm_dp_mst_topology_mgr *mgr,
 					   struct drm_connector *connector)
 {
 	struct intel_connector *intel_connector = to_intel_connector(connector);
 	struct drm_device *dev = connector->dev;

 	drm_connector_unregister(connector);

 	/* need to nuke the connector */
 	drm_modeset_lock_all(dev);
 	intel_connector_remove_from_fbdev(intel_connector);
 	intel_connector->mst_port = NULL;
 	drm_modeset_unlock_all(dev);

 	drm_connector_unreference(&intel_connector->base);
 	DRM_DEBUG_KMS("\n");
 }

 static void intel_dp_mst_hotplug(struct drm_dp_mst_topology_mgr *mgr)
 {
 	struct intel_dp *intel_dp = container_of(mgr, struct intel_dp, mst_mgr);
 	struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
 	struct drm_device *dev = intel_dig_port->base.base.dev;

 	drm_kms_helper_hotplug_event(dev);
 }

 static const struct drm_dp_mst_topology_cbs mst_cbs = {
 	.add_connector = intel_dp_add_mst_connector,
 	.register_connector = intel_dp_register_mst_connector,
 	.destroy_connector = intel_dp_destroy_mst_connector,
 	.hotplug = intel_dp_mst_hotplug,
 };

 static struct intel_dp_mst_encoder *
 intel_dp_create_fake_mst_encoder(struct intel_digital_port *intel_dig_port, enum pipe pipe)
 {
 	struct intel_dp_mst_encoder *intel_mst;
 	struct intel_encoder *intel_encoder;
 	struct drm_device *dev = intel_dig_port->base.base.dev;

 	intel_mst = kzalloc(sizeof(*intel_mst), GFP_KERNEL);

 	if (!intel_mst)
 		return NULL;

 	intel_mst->pipe = pipe;
 	intel_encoder = &intel_mst->base;
 	intel_mst->primary = intel_dig_port;

 	drm_encoder_init(dev, &intel_encoder->base, &intel_dp_mst_enc_funcs,
 			 DRM_MODE_ENCODER_DPMST, "DP-MST %c", pipe_name(pipe));

 	intel_encoder->type = INTEL_OUTPUT_DP_MST;
 	intel_encoder->crtc_mask = 0x7;
 	intel_encoder->cloneable = 0;

 	intel_encoder->compute_config = intel_dp_mst_compute_config;
 	intel_encoder->disable = intel_mst_disable_dp;
 	intel_encoder->post_disable = intel_mst_post_disable_dp;
 	intel_encoder->pre_enable = intel_mst_pre_enable_dp;
 	intel_encoder->enable = intel_mst_enable_dp;
 	intel_encoder->get_hw_state = intel_dp_mst_enc_get_hw_state;
 	intel_encoder->get_config = intel_dp_mst_enc_get_config;

 	return intel_mst;

 }

 static bool
 intel_dp_create_fake_mst_encoders(struct intel_digital_port *intel_dig_port)
 {
 	int i;
 	struct intel_dp *intel_dp = &intel_dig_port->dp;

 	for (i = PIPE_A; i <= PIPE_C; i++)
 		intel_dp->mst_encoders[i] = intel_dp_create_fake_mst_encoder(intel_dig_port, i);
 	return true;
 }

 int
 intel_dp_mst_encoder_init(struct intel_digital_port *intel_dig_port, int conn_base_id)
 {
 	struct intel_dp *intel_dp = &intel_dig_port->dp;
 	struct drm_device *dev = intel_dig_port->base.base.dev;
 	int ret;

 	intel_dp->can_mst = true;
 	intel_dp->mst_mgr.cbs = &mst_cbs;

 	/* create encoders */
 	intel_dp_create_fake_mst_encoders(intel_dig_port);
 	ret = drm_dp_mst_topology_mgr_init(&intel_dp->mst_mgr, dev->dev, &intel_dp->aux, 16, 3, conn_base_id);
 	if (ret) {
 		intel_dp->can_mst = false;
 		return ret;
 	}
 	return 0;
 }

 void
 intel_dp_mst_encoder_cleanup(struct intel_digital_port *intel_dig_port)
 {
 	struct intel_dp *intel_dp = &intel_dig_port->dp;

 	if (!intel_dp->can_mst)
 		return;

 	drm_dp_mst_topology_mgr_destroy(&intel_dp->mst_mgr);
 	/* encoders will get killed by normal cleanup */
 }
	/*
	* Copyright © 2008 Intel Corporation
	* 2014 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 (including the next
	* paragraph) 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 AUTHORS OR COPYRIGHT HOLDERS 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.
	*
	*/

	#include <drm/drmP.h>
	#include "i915_drv.h"
	#include "intel_drv.h"
	#include <drm/drm_atomic_helper.h>
	#include <drm/drm_crtc_helper.h>
	#include <drm/drm_edid.h>

	static bool intel_dp_mst_compute_config(struct intel_encoder *encoder,
	struct intel_crtc_state *pipe_config)
	{
	struct intel_dp_mst_encoder *intel_mst = enc_to_mst(&encoder->base);
	struct intel_digital_port *intel_dig_port = intel_mst->primary;
	struct intel_dp *intel_dp = &intel_dig_port->dp;
	struct drm_atomic_state *state;
	int bpp, i;
	int lane_count, slots;
	const struct drm_display_mode *adjusted_mode = &pipe_config->base.adjusted_mode;
	struct drm_connector *drm_connector;
	struct intel_connector connector, found = NULL;
	struct drm_connector_state *connector_state;
	int mst_pbn;

	pipe_config->dp_encoder_is_mst = true;
	pipe_config->has_pch_encoder = false;
	pipe_config->has_dp_encoder = true;
	bpp = 24;
	/*
	* for MST we always configure max link bw - the spec doesn't
	* seem to suggest we should do otherwise.
	*/
	lane_count = drm_dp_max_lane_count(intel_dp->dpcd);


	pipe_config->lane_count = lane_count;

	pipe_config->pipe_bpp = 24;
	pipe_config->port_clock = intel_dp_max_link_rate(intel_dp);

	state = pipe_config->base.state;

	for_each_connector_in_state(state, drm_connector, connector_state, i) {
	connector = to_intel_connector(drm_connector);

	if (connector_state->best_encoder == &encoder->base) {
	found = connector;
	break;
	}
	}

	if (!found) {
	DRM_ERROR("can't find connector\n");
	return false;
	}

	mst_pbn = drm_dp_calc_pbn_mode(adjusted_mode->crtc_clock, bpp);

	pipe_config->pbn = mst_pbn;
	slots = drm_dp_find_vcpi_slots(&intel_dp->mst_mgr, mst_pbn);

	intel_link_compute_m_n(bpp, lane_count,
	adjusted_mode->crtc_clock,
	pipe_config->port_clock,
	&pipe_config->dp_m_n);

	pipe_config->dp_m_n.tu = slots;

	return true;

	}

	static void intel_mst_disable_dp(struct intel_encoder *encoder)
	{
	struct intel_dp_mst_encoder *intel_mst = enc_to_mst(&encoder->base);
	struct intel_digital_port *intel_dig_port = intel_mst->primary;
	struct intel_dp *intel_dp = &intel_dig_port->dp;
	int ret;

	DRM_DEBUG_KMS("%d\n", intel_dp->active_mst_links);

	drm_dp_mst_reset_vcpi_slots(&intel_dp->mst_mgr, intel_mst->connector->port);

	ret = drm_dp_update_payload_part1(&intel_dp->mst_mgr);
	if (ret) {
	DRM_ERROR("failed to update payload %d\n", ret);
	}
	}

	static void intel_mst_post_disable_dp(struct intel_encoder *encoder)
	{
	struct intel_dp_mst_encoder *intel_mst = enc_to_mst(&encoder->base);
	struct intel_digital_port *intel_dig_port = intel_mst->primary;
	struct intel_dp *intel_dp = &intel_dig_port->dp;

	DRM_DEBUG_KMS("%d\n", intel_dp->active_mst_links);

	/* this can fail */
	drm_dp_check_act_status(&intel_dp->mst_mgr);
	/* and this can also fail */
	drm_dp_update_payload_part2(&intel_dp->mst_mgr);

	drm_dp_mst_deallocate_vcpi(&intel_dp->mst_mgr, intel_mst->connector->port);

	intel_dp->active_mst_links--;

	intel_mst->connector = NULL;
	if (intel_dp->active_mst_links == 0) {
	intel_dig_port->base.post_disable(&intel_dig_port->base);
	intel_dp_sink_dpms(intel_dp, DRM_MODE_DPMS_OFF);
	}
	}

	static void intel_mst_pre_enable_dp(struct intel_encoder *encoder)
	{
	struct intel_dp_mst_encoder *intel_mst = enc_to_mst(&encoder->base);
	struct intel_digital_port *intel_dig_port = intel_mst->primary;
	struct intel_dp *intel_dp = &intel_dig_port->dp;
	struct drm_device *dev = encoder->base.dev;
	struct drm_i915_private *dev_priv = dev->dev_private;
	enum port port = intel_dig_port->port;
	int ret;
	uint32_t temp;
	struct intel_connector found = NULL, connector;
	int slots;
	struct drm_crtc *crtc = encoder->base.crtc;
	struct intel_crtc *intel_crtc = to_intel_crtc(crtc);

	for_each_intel_connector(dev, connector) {
	if (connector->base.state->best_encoder == &encoder->base) {
	found = connector;
	break;
	}
	}

	if (!found) {
	DRM_ERROR("can't find connector\n");
	return;
	}

	/* MST encoders are bound to a crtc, not to a connector,
	* force the mapping here for get_hw_state.
	*/
	found->encoder = encoder;

	DRM_DEBUG_KMS("%d\n", intel_dp->active_mst_links);

	intel_mst->connector = found;

	if (intel_dp->active_mst_links == 0) {
	intel_prepare_ddi_buffer(&intel_dig_port->base);

	intel_ddi_clk_select(&intel_dig_port->base, intel_crtc->config);

	intel_dp_set_link_params(intel_dp, intel_crtc->config);

	intel_ddi_init_dp_buf_reg(&intel_dig_port->base);

	intel_dp_sink_dpms(intel_dp, DRM_MODE_DPMS_ON);

	intel_dp_start_link_train(intel_dp);
	intel_dp_stop_link_train(intel_dp);
	}

	ret = drm_dp_mst_allocate_vcpi(&intel_dp->mst_mgr,
	intel_mst->connector->port,
	intel_crtc->config->pbn, &slots);
	if (ret == false) {
	DRM_ERROR("failed to allocate vcpi\n");
	return;
	}


	intel_dp->active_mst_links++;
	temp = I915_READ(DP_TP_STATUS(port));
	I915_WRITE(DP_TP_STATUS(port), temp);

	ret = drm_dp_update_payload_part1(&intel_dp->mst_mgr);
	}

	static void intel_mst_enable_dp(struct intel_encoder *encoder)
	{
	struct intel_dp_mst_encoder *intel_mst = enc_to_mst(&encoder->base);
	struct intel_digital_port *intel_dig_port = intel_mst->primary;
	struct intel_dp *intel_dp = &intel_dig_port->dp;
	struct drm_device *dev = intel_dig_port->base.base.dev;
	struct drm_i915_private *dev_priv = dev->dev_private;
	enum port port = intel_dig_port->port;
	int ret;

	DRM_DEBUG_KMS("%d\n", intel_dp->active_mst_links);

	if (wait_for((I915_READ(DP_TP_STATUS(port)) & DP_TP_STATUS_ACT_SENT),
	1))
	DRM_ERROR("Timed out waiting for ACT sent\n");

	ret = drm_dp_check_act_status(&intel_dp->mst_mgr);

	ret = drm_dp_update_payload_part2(&intel_dp->mst_mgr);
	}

	static bool intel_dp_mst_enc_get_hw_state(struct intel_encoder *encoder,
	enum pipe *pipe)
	{
	struct intel_dp_mst_encoder *intel_mst = enc_to_mst(&encoder->base);
	*pipe = intel_mst->pipe;
	if (intel_mst->connector)
	return true;
	return false;
	}

	static void intel_dp_mst_enc_get_config(struct intel_encoder *encoder,
	struct intel_crtc_state *pipe_config)
	{
	struct intel_dp_mst_encoder *intel_mst = enc_to_mst(&encoder->base);
	struct intel_digital_port *intel_dig_port = intel_mst->primary;
	struct intel_crtc *crtc = to_intel_crtc(encoder->base.crtc);
	struct drm_device *dev = encoder->base.dev;
	struct drm_i915_private *dev_priv = dev->dev_private;
	enum transcoder cpu_transcoder = pipe_config->cpu_transcoder;
	u32 temp, flags = 0;

	pipe_config->has_dp_encoder = true;

	temp = I915_READ(TRANS_DDI_FUNC_CTL(cpu_transcoder));
	if (temp & TRANS_DDI_PHSYNC)
	flags \|= DRM_MODE_FLAG_PHSYNC;
	else
	flags \|= DRM_MODE_FLAG_NHSYNC;
	if (temp & TRANS_DDI_PVSYNC)
	flags \|= DRM_MODE_FLAG_PVSYNC;
	else
	flags \|= DRM_MODE_FLAG_NVSYNC;

	switch (temp & TRANS_DDI_BPC_MASK) {
	case TRANS_DDI_BPC_6:
	pipe_config->pipe_bpp = 18;
	break;
	case TRANS_DDI_BPC_8:
	pipe_config->pipe_bpp = 24;
	break;
	case TRANS_DDI_BPC_10:
	pipe_config->pipe_bpp = 30;
	break;
	case TRANS_DDI_BPC_12:
	pipe_config->pipe_bpp = 36;
	break;
	default:
	break;
	}
	pipe_config->base.adjusted_mode.flags \|= flags;

	pipe_config->lane_count =
	((temp & DDI_PORT_WIDTH_MASK) >> DDI_PORT_WIDTH_SHIFT) + 1;

	intel_dp_get_m_n(crtc, pipe_config);

	intel_ddi_clock_get(&intel_dig_port->base, pipe_config);
	}

	static int intel_dp_mst_get_ddc_modes(struct drm_connector *connector)
	{
	struct intel_connector *intel_connector = to_intel_connector(connector);
	struct intel_dp *intel_dp = intel_connector->mst_port;
	struct edid *edid;
	int ret;

	if (!intel_dp) {
	return intel_connector_update_modes(connector, NULL);
	}

	edid = drm_dp_mst_get_edid(connector, &intel_dp->mst_mgr, intel_connector->port);
	ret = intel_connector_update_modes(connector, edid);
	kfree(edid);

	return ret;
	}

	static enum drm_connector_status
	intel_dp_mst_detect(struct drm_connector *connector, bool force)
	{
	struct intel_connector *intel_connector = to_intel_connector(connector);
	struct intel_dp *intel_dp = intel_connector->mst_port;

	if (!intel_dp)
	return connector_status_disconnected;
	return drm_dp_mst_detect_port(connector, &intel_dp->mst_mgr, intel_connector->port);
	}

	static int
	intel_dp_mst_set_property(struct drm_connector *connector,
	struct drm_property *property,
	uint64_t val)
	{
	return 0;
	}

	static void
	intel_dp_mst_connector_destroy(struct drm_connector *connector)
	{
	struct intel_connector *intel_connector = to_intel_connector(connector);

	if (!IS_ERR_OR_NULL(intel_connector->edid))
	kfree(intel_connector->edid);

	drm_connector_cleanup(connector);
	kfree(connector);
	}

	static const struct drm_connector_funcs intel_dp_mst_connector_funcs = {
	.dpms = drm_atomic_helper_connector_dpms,
	.detect = intel_dp_mst_detect,
	.fill_modes = drm_helper_probe_single_connector_modes,
	.set_property = intel_dp_mst_set_property,
	.atomic_get_property = intel_connector_atomic_get_property,
	.early_unregister = intel_connector_unregister,
	.destroy = intel_dp_mst_connector_destroy,
	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
	};

	static int intel_dp_mst_get_modes(struct drm_connector *connector)
	{
	return intel_dp_mst_get_ddc_modes(connector);
	}

	static enum drm_mode_status
	intel_dp_mst_mode_valid(struct drm_connector *connector,
	struct drm_display_mode *mode)
	{
	int max_dotclk = to_i915(connector->dev)->max_dotclk_freq;

	/* TODO - validate mode against available PBN for link */
	if (mode->clock < 10000)
	return MODE_CLOCK_LOW;

	if (mode->flags & DRM_MODE_FLAG_DBLCLK)
	return MODE_H_ILLEGAL;

	if (mode->clock > max_dotclk)
	return MODE_CLOCK_HIGH;

	return MODE_OK;
	}

	static struct drm_encoder intel_mst_atomic_best_encoder(struct drm_connector connector,
	struct drm_connector_state *state)
	{
	struct intel_connector *intel_connector = to_intel_connector(connector);
	struct intel_dp *intel_dp = intel_connector->mst_port;
	struct intel_crtc *crtc = to_intel_crtc(state->crtc);

	if (!intel_dp)
	return NULL;
	return &intel_dp->mst_encoders[crtc->pipe]->base.base;
	}

	static struct drm_encoder intel_mst_best_encoder(struct drm_connector connector)
	{
	struct intel_connector *intel_connector = to_intel_connector(connector);
	struct intel_dp *intel_dp = intel_connector->mst_port;
	if (!intel_dp)
	return NULL;
	return &intel_dp->mst_encoders[0]->base.base;
	}

	static const struct drm_connector_helper_funcs intel_dp_mst_connector_helper_funcs = {
	.get_modes = intel_dp_mst_get_modes,
	.mode_valid = intel_dp_mst_mode_valid,
	.atomic_best_encoder = intel_mst_atomic_best_encoder,
	.best_encoder = intel_mst_best_encoder,
	};

	static void intel_dp_mst_encoder_destroy(struct drm_encoder *encoder)
	{
	struct intel_dp_mst_encoder *intel_mst = enc_to_mst(encoder);

	drm_encoder_cleanup(encoder);
	kfree(intel_mst);
	}

	static const struct drm_encoder_funcs intel_dp_mst_enc_funcs = {
	.destroy = intel_dp_mst_encoder_destroy,
	};

	static bool intel_dp_mst_get_hw_state(struct intel_connector *connector)
	{
	if (connector->encoder && connector->base.state->crtc) {
	enum pipe pipe;
	if (!connector->encoder->get_hw_state(connector->encoder, &pipe))
	return false;
	return true;
	}
	return false;
	}

	static void intel_connector_add_to_fbdev(struct intel_connector *connector)
	{
	#ifdef CONFIG_DRM_FBDEV_EMULATION
	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);

	if (dev_priv->fbdev)
	drm_fb_helper_add_one_connector(&dev_priv->fbdev->helper,
	&connector->base);
	#endif
	}

	static void intel_connector_remove_from_fbdev(struct intel_connector *connector)
	{
	#ifdef CONFIG_DRM_FBDEV_EMULATION
	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);

	if (dev_priv->fbdev)
	drm_fb_helper_remove_one_connector(&dev_priv->fbdev->helper,
	&connector->base);
	#endif
	}

	static struct drm_connector intel_dp_add_mst_connector(struct drm_dp_mst_topology_mgr mgr, struct drm_dp_mst_port port, const char pathprop)
	{
	struct intel_dp *intel_dp = container_of(mgr, struct intel_dp, mst_mgr);
	struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
	struct drm_device *dev = intel_dig_port->base.base.dev;
	struct intel_connector *intel_connector;
	struct drm_connector *connector;
	int i;

	intel_connector = intel_connector_alloc();
	if (!intel_connector)
	return NULL;

	connector = &intel_connector->base;
	drm_connector_init(dev, connector, &intel_dp_mst_connector_funcs, DRM_MODE_CONNECTOR_DisplayPort);
	drm_connector_helper_add(connector, &intel_dp_mst_connector_helper_funcs);

	intel_connector->get_hw_state = intel_dp_mst_get_hw_state;
	intel_connector->mst_port = intel_dp;
	intel_connector->port = port;

	for (i = PIPE_A; i <= PIPE_C; i++) {
	drm_mode_connector_attach_encoder(&intel_connector->base,
	&intel_dp->mst_encoders[i]->base.base);
	}
	intel_dp_add_properties(intel_dp, connector);

	drm_object_attach_property(&connector->base, dev->mode_config.path_property, 0);
	drm_object_attach_property(&connector->base, dev->mode_config.tile_property, 0);

	drm_mode_connector_set_path_property(connector, pathprop);
	return connector;
	}

	static void intel_dp_register_mst_connector(struct drm_connector *connector)
	{
	struct intel_connector *intel_connector = to_intel_connector(connector);
	struct drm_device *dev = connector->dev;
	drm_modeset_lock_all(dev);
	intel_connector_add_to_fbdev(intel_connector);
	drm_modeset_unlock_all(dev);
	drm_connector_register(&intel_connector->base);
	}

	static void intel_dp_destroy_mst_connector(struct drm_dp_mst_topology_mgr *mgr,
	struct drm_connector *connector)
	{
	struct intel_connector *intel_connector = to_intel_connector(connector);
	struct drm_device *dev = connector->dev;

	drm_connector_unregister(connector);

	/* need to nuke the connector */
	drm_modeset_lock_all(dev);
	intel_connector_remove_from_fbdev(intel_connector);
	intel_connector->mst_port = NULL;
	drm_modeset_unlock_all(dev);

	drm_connector_unreference(&intel_connector->base);
	DRM_DEBUG_KMS("\n");
	}

	static void intel_dp_mst_hotplug(struct drm_dp_mst_topology_mgr *mgr)
	{
	struct intel_dp *intel_dp = container_of(mgr, struct intel_dp, mst_mgr);
	struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
	struct drm_device *dev = intel_dig_port->base.base.dev;

	drm_kms_helper_hotplug_event(dev);
	}

	static const struct drm_dp_mst_topology_cbs mst_cbs = {
	.add_connector = intel_dp_add_mst_connector,
	.register_connector = intel_dp_register_mst_connector,
	.destroy_connector = intel_dp_destroy_mst_connector,
	.hotplug = intel_dp_mst_hotplug,
	};

	static struct intel_dp_mst_encoder *
	intel_dp_create_fake_mst_encoder(struct intel_digital_port *intel_dig_port, enum pipe pipe)
	{
	struct intel_dp_mst_encoder *intel_mst;
	struct intel_encoder *intel_encoder;
	struct drm_device *dev = intel_dig_port->base.base.dev;

	intel_mst = kzalloc(sizeof(*intel_mst), GFP_KERNEL);

	if (!intel_mst)
	return NULL;

	intel_mst->pipe = pipe;
	intel_encoder = &intel_mst->base;
	intel_mst->primary = intel_dig_port;

	drm_encoder_init(dev, &intel_encoder->base, &intel_dp_mst_enc_funcs,
	DRM_MODE_ENCODER_DPMST, "DP-MST %c", pipe_name(pipe));

	intel_encoder->type = INTEL_OUTPUT_DP_MST;
	intel_encoder->crtc_mask = 0x7;
	intel_encoder->cloneable = 0;

	intel_encoder->compute_config = intel_dp_mst_compute_config;
	intel_encoder->disable = intel_mst_disable_dp;
	intel_encoder->post_disable = intel_mst_post_disable_dp;
	intel_encoder->pre_enable = intel_mst_pre_enable_dp;
	intel_encoder->enable = intel_mst_enable_dp;
	intel_encoder->get_hw_state = intel_dp_mst_enc_get_hw_state;
	intel_encoder->get_config = intel_dp_mst_enc_get_config;

	return intel_mst;

	}

	static bool
	intel_dp_create_fake_mst_encoders(struct intel_digital_port *intel_dig_port)
	{
	int i;
	struct intel_dp *intel_dp = &intel_dig_port->dp;

	for (i = PIPE_A; i <= PIPE_C; i++)
	intel_dp->mst_encoders[i] = intel_dp_create_fake_mst_encoder(intel_dig_port, i);
	return true;
	}

	int
	intel_dp_mst_encoder_init(struct intel_digital_port *intel_dig_port, int conn_base_id)
	{
	struct intel_dp *intel_dp = &intel_dig_port->dp;
	struct drm_device *dev = intel_dig_port->base.base.dev;
	int ret;

	intel_dp->can_mst = true;
	intel_dp->mst_mgr.cbs = &mst_cbs;

	/* create encoders */
	intel_dp_create_fake_mst_encoders(intel_dig_port);
	ret = drm_dp_mst_topology_mgr_init(&intel_dp->mst_mgr, dev->dev, &intel_dp->aux, 16, 3, conn_base_id);
	if (ret) {
	intel_dp->can_mst = false;
	return ret;
	}
	return 0;
	}

	void
	intel_dp_mst_encoder_cleanup(struct intel_digital_port *intel_dig_port)
	{
	struct intel_dp *intel_dp = &intel_dig_port->dp;

	if (!intel_dp->can_mst)
	return;

	drm_dp_mst_topology_mgr_destroy(&intel_dp->mst_mgr);
	/* encoders will get killed by normal cleanup */
	}