/*
 * 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 drm_connector_state *conn_state)
{
        struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
        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_connector *connector = conn_state->connector;
        void *port = to_intel_connector(connector)->port;
        struct drm_atomic_state *state = pipe_config->base.state;
        int bpp;
        int lane_count, slots = 0;
        const struct drm_display_mode *adjusted_mode = &pipe_config->base.adjusted_mode;
        int mst_pbn;
        bool constant_n = drm_dp_has_quirk(&intel_dp->desc,
                                           DP_DPCD_QUIRK_CONSTANT_N);

        if (adjusted_mode->flags & DRM_MODE_FLAG_DBLSCAN)
                return false;

        pipe_config->has_pch_encoder = false;
        bpp = 24;
        if (intel_dp->compliance.test_data.bpc) {
                bpp = intel_dp->compliance.test_data.bpc * 3;
                DRM_DEBUG_KMS("Setting pipe bpp to %d\n",
                              bpp);
        }
        /*
         * for MST we always configure max link bw - the spec doesn't
         * seem to suggest we should do otherwise.
         */
        lane_count = intel_dp_max_lane_count(intel_dp);

        pipe_config->lane_count = lane_count;

        pipe_config->pipe_bpp = bpp;

        pipe_config->port_clock = intel_dp_max_link_rate(intel_dp);

        if (drm_dp_mst_port_has_audio(&intel_dp->mst_mgr, port))
                pipe_config->has_audio = true;

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

        /* Zombie connectors can't have VCPI slots */
        if (!drm_connector_is_unregistered(connector)) {
                slots = drm_dp_atomic_find_vcpi_slots(state,
                                                      &intel_dp->mst_mgr,
                                                      port,
                                                      mst_pbn);
                if (slots < 0) {
                        DRM_DEBUG_KMS("failed finding vcpi slots:%d\n",
                                      slots);
                        return false;
                }
        }

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

        pipe_config->dp_m_n.tu = slots;

        if (IS_GEN9_LP(dev_priv))
                pipe_config->lane_lat_optim_mask =
                        bxt_ddi_phy_calc_lane_lat_optim_mask(pipe_config->lane_count);

        intel_ddi_compute_min_voltage_level(dev_priv, pipe_config);

        return true;
}

static int intel_dp_mst_atomic_check(struct drm_connector *connector,
                struct drm_connector_state *new_conn_state)
{
        struct drm_atomic_state *state = new_conn_state->state;
        struct drm_connector_state *old_conn_state;
        struct drm_crtc *old_crtc;
        struct drm_crtc_state *crtc_state;
        int slots, ret = 0;

        old_conn_state = drm_atomic_get_old_connector_state(state, connector);
        old_crtc = old_conn_state->crtc;
        if (!old_crtc)
                return ret;

        crtc_state = drm_atomic_get_new_crtc_state(state, old_crtc);
        slots = to_intel_crtc_state(crtc_state)->dp_m_n.tu;
        if (drm_atomic_crtc_needs_modeset(crtc_state) && slots > 0) {
                struct drm_dp_mst_topology_mgr *mgr;
                struct drm_encoder *old_encoder;

                old_encoder = old_conn_state->best_encoder;
                mgr = &enc_to_mst(old_encoder)->primary->dp.mst_mgr;

                ret = drm_dp_atomic_release_vcpi_slots(state, mgr, slots);
                if (ret)
                        DRM_DEBUG_KMS("failed releasing %d vcpi slots:%d\n", slots, ret);
                else
                        to_intel_crtc_state(crtc_state)->dp_m_n.tu = 0;
        }
        return ret;
}

static void intel_mst_disable_dp(struct intel_encoder *encoder,
                                 const struct intel_crtc_state *old_crtc_state,
                                 const struct drm_connector_state *old_conn_state)
{
        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 intel_connector *connector =
                to_intel_connector(old_conn_state->connector);
        int ret;

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

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

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

static void intel_mst_post_disable_dp(struct intel_encoder *encoder,
                                      const struct intel_crtc_state *old_crtc_state,
                                      const struct drm_connector_state *old_conn_state)
{
        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 intel_connector *connector =
                to_intel_connector(old_conn_state->connector);

        intel_ddi_disable_pipe_clock(old_crtc_state);

        /* 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, connector->port);

        /*
         * Power down mst path before disabling the port, otherwise we end
         * up getting interrupts from the sink upon detecting link loss.
         */
        drm_dp_send_power_updown_phy(&intel_dp->mst_mgr, connector->port,
                                     false);

        intel_dp->active_mst_links--;

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

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

static void intel_mst_pre_pll_enable_dp(struct intel_encoder *encoder,
                                        const struct intel_crtc_state *pipe_config,
                                        const struct drm_connector_state *conn_state)
{
        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;

        if (intel_dp->active_mst_links == 0 &&
            intel_dig_port->base.pre_pll_enable)
                intel_dig_port->base.pre_pll_enable(&intel_dig_port->base,
                                                    pipe_config, NULL);
}

static void intel_mst_pre_enable_dp(struct intel_encoder *encoder,
                                    const struct intel_crtc_state *pipe_config,
                                    const struct drm_connector_state *conn_state)
{
        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_i915_private *dev_priv = to_i915(encoder->base.dev);
        enum port port = intel_dig_port->base.port;
        struct intel_connector *connector =
                to_intel_connector(conn_state->connector);
        int ret;
        uint32_t temp;

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

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

        if (intel_dp->active_mst_links == 0)
                intel_dp_sink_dpms(intel_dp, DRM_MODE_DPMS_ON);

        drm_dp_send_power_updown_phy(&intel_dp->mst_mgr, connector->port, true);

        if (intel_dp->active_mst_links == 0)
                intel_dig_port->base.pre_enable(&intel_dig_port->base,
                                                pipe_config, NULL);

        ret = drm_dp_mst_allocate_vcpi(&intel_dp->mst_mgr,
                                       connector->port,
                                       pipe_config->pbn,
                                       pipe_config->dp_m_n.tu);
        if (!ret)
                DRM_ERROR("failed to allocate vcpi\n");

        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);

        intel_ddi_enable_pipe_clock(pipe_config);
}

static void intel_mst_enable_dp(struct intel_encoder *encoder,
                                const struct intel_crtc_state *pipe_config,
                                const struct drm_connector_state *conn_state)
{
        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_i915_private *dev_priv = to_i915(encoder->base.dev);
        enum port port = intel_dig_port->base.port;

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

        if (intel_wait_for_register(dev_priv,
                                    DP_TP_STATUS(port),
                                    DP_TP_STATUS_ACT_SENT,
                                    DP_TP_STATUS_ACT_SENT,
                                    1))
                DRM_ERROR("Timed out waiting for ACT sent\n");

        drm_dp_check_act_status(&intel_dp->mst_mgr);

        drm_dp_update_payload_part2(&intel_dp->mst_mgr);
        if (pipe_config->has_audio)
                intel_audio_codec_enable(encoder, pipe_config, conn_state);
}

static bool intel_dp_mst_enc_get_hw_state(struct intel_encoder *encoder,
                                      enum i915_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;

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

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 = {
        .detect = intel_dp_mst_detect,
        .fill_modes = drm_helper_probe_single_connector_modes,
        .late_register = intel_connector_register,
        .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)
{
        struct intel_connector *intel_connector = to_intel_connector(connector);
        struct intel_dp *intel_dp = intel_connector->mst_port;
        int max_dotclk = to_i915(connector->dev)->max_dotclk_freq;
        int bpp = 24; /* MST uses fixed bpp */
        int max_rate, mode_rate, max_lanes, max_link_clock;

        if (drm_connector_is_unregistered(connector))
                return MODE_ERROR;

        if (mode->flags & DRM_MODE_FLAG_DBLSCAN)
                return MODE_NO_DBLESCAN;

        max_link_clock = intel_dp_max_link_rate(intel_dp);
        max_lanes = intel_dp_max_lane_count(intel_dp);

        max_rate = intel_dp_max_data_rate(max_link_clock, max_lanes);
        mode_rate = intel_dp_link_required(mode->clock, bpp);

        /* 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_rate > max_rate || 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);

        return &intel_dp->mst_encoders[crtc->pipe]->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,
        .atomic_check = intel_dp_mst_atomic_check,
};

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 i915_pipe pipe;
                if (!connector->encoder->get_hw_state(connector->encoder, &pipe))
                        return false;
                return true;
        }
        return false;
}

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 drm_i915_private *dev_priv = to_i915(dev);
        struct intel_connector *intel_connector;
        struct drm_connector *connector;
        enum i915_pipe pipe;
        int ret;

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

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

        connector = &intel_connector->base;
        ret = drm_connector_init(dev, connector, &intel_dp_mst_connector_funcs,
                                 DRM_MODE_CONNECTOR_DisplayPort);
        if (ret) {
                intel_connector_free(intel_connector);
                return NULL;
        }

        drm_connector_helper_add(connector, &intel_dp_mst_connector_helper_funcs);

        for_each_pipe(dev_priv, pipe) {
                struct drm_encoder *enc =
                        &intel_dp->mst_encoders[pipe]->base.base;

                ret = drm_connector_attach_encoder(&intel_connector->base, enc);
                if (ret)
                        goto err;
        }

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

        ret = drm_connector_set_path_property(connector, pathprop);
        if (ret)
                goto err;

        return connector;

err:
        drm_connector_cleanup(connector);
        return NULL;
}

static void intel_dp_register_mst_connector(struct drm_connector *connector)
{
        struct drm_i915_private *dev_priv = to_i915(connector->dev);

        if (dev_priv->fbdev)
                drm_fb_helper_add_one_connector(&dev_priv->fbdev->helper,
                                                connector);

        drm_connector_register(connector);
}

static void intel_dp_destroy_mst_connector(struct drm_dp_mst_topology_mgr *mgr,
                                           struct drm_connector *connector)
{
        struct drm_i915_private *dev_priv = to_i915(connector->dev);

        DRM_DEBUG_KMS("[CONNECTOR:%d:%s]\n", connector->base.id, connector->name);
        drm_connector_unregister(connector);

        if (dev_priv->fbdev)
                drm_fb_helper_remove_one_connector(&dev_priv->fbdev->helper,
                                                   connector);

        drm_connector_put(connector);
}

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 i915_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->power_domain = intel_dig_port->base.power_domain;
        intel_encoder->port = intel_dig_port->base.port;
        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_pll_enable = intel_mst_pre_pll_enable_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)
{
        struct intel_dp *intel_dp = &intel_dig_port->dp;
        struct drm_i915_private *dev_priv = to_i915(intel_dig_port->base.base.dev);
        enum i915_pipe pipe;

        for_each_pipe(dev_priv, pipe)
                intel_dp->mst_encoders[pipe] = intel_dp_create_fake_mst_encoder(intel_dig_port, pipe);
        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,
                                           &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 */
}