/*
 * Copyright © 2013 Intel Corporation
 *
 * 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.
 *
 * Author: Jani Nikula <jani.nikula@intel.com>
 */

#include <linux/gpio/consumer.h>
#include <linux/slab.h>

#include <drm/drm_atomic_helper.h>
#include <drm/drm_crtc.h>
#include <drm/drm_edid.h>
#include <drm/drm_mipi_dsi.h>

#include "i915_drv.h"
#include "intel_atomic.h"
#include "intel_connector.h"
#include "intel_drv.h"
#include "intel_dsi.h"
#include "intel_fifo_underrun.h"
#include "intel_panel.h"
#include "intel_sideband.h"

/* return pixels in terms of txbyteclkhs */
static u16 txbyteclkhs(u16 pixels, int bpp, int lane_count,
                       u16 burst_mode_ratio)
{
        return DIV_ROUND_UP(DIV_ROUND_UP(pixels * bpp * burst_mode_ratio,
                                         8 * 100), lane_count);
}

/* return pixels equvalent to txbyteclkhs */
static u16 pixels_from_txbyteclkhs(u16 clk_hs, int bpp, int lane_count,
                        u16 burst_mode_ratio)
{
        return DIV_ROUND_UP((clk_hs * lane_count * 8 * 100),
                                                (bpp * burst_mode_ratio));
}

enum mipi_dsi_pixel_format pixel_format_from_register_bits(u32 fmt)
{
        /* It just so happens the VBT matches register contents. */
        switch (fmt) {
        case VID_MODE_FORMAT_RGB888:
                return MIPI_DSI_FMT_RGB888;
        case VID_MODE_FORMAT_RGB666:
                return MIPI_DSI_FMT_RGB666;
        case VID_MODE_FORMAT_RGB666_PACKED:
                return MIPI_DSI_FMT_RGB666_PACKED;
        case VID_MODE_FORMAT_RGB565:
                return MIPI_DSI_FMT_RGB565;
        default:
                MISSING_CASE(fmt);
                return MIPI_DSI_FMT_RGB666;
        }
}

void vlv_dsi_wait_for_fifo_empty(struct intel_dsi *intel_dsi, enum port port)
{
        struct drm_encoder *encoder = &intel_dsi->base.base;
        struct drm_device *dev = encoder->dev;
        struct drm_i915_private *dev_priv = to_i915(dev);
        u32 mask;

        mask = LP_CTRL_FIFO_EMPTY | HS_CTRL_FIFO_EMPTY |
                LP_DATA_FIFO_EMPTY | HS_DATA_FIFO_EMPTY;

        if (intel_wait_for_register(&dev_priv->uncore,
                                    MIPI_GEN_FIFO_STAT(port), mask, mask,
                                    100))
                DRM_ERROR("DPI FIFOs are not empty\n");
}

static void write_data(struct drm_i915_private *dev_priv,
                       i915_reg_t reg,
                       const u8 *data, u32 len)
{
        u32 i, j;

        for (i = 0; i < len; i += 4) {
                u32 val = 0;

                for (j = 0; j < min_t(u32, len - i, 4); j++)
                        val |= *data++ << 8 * j;

                I915_WRITE(reg, val);
        }
}

static void read_data(struct drm_i915_private *dev_priv,
                      i915_reg_t reg,
                      u8 *data, u32 len)
{
        u32 i, j;

        for (i = 0; i < len; i += 4) {
                u32 val = I915_READ(reg);

                for (j = 0; j < min_t(u32, len - i, 4); j++)
                        *data++ = val >> 8 * j;
        }
}

static ssize_t intel_dsi_host_transfer(struct mipi_dsi_host *host,
                                       const struct mipi_dsi_msg *msg)
{
        struct intel_dsi_host *intel_dsi_host = to_intel_dsi_host(host);
        struct drm_device *dev = intel_dsi_host->intel_dsi->base.base.dev;
        struct drm_i915_private *dev_priv = to_i915(dev);
        enum port port = intel_dsi_host->port;
        struct mipi_dsi_packet packet;
        ssize_t ret;
        const u8 *header, *data;
        i915_reg_t data_reg, ctrl_reg;
        u32 data_mask, ctrl_mask;

        ret = mipi_dsi_create_packet(&packet, msg);
        if (ret < 0)
                return ret;

        header = packet.header;
        data = packet.payload;

        if (msg->flags & MIPI_DSI_MSG_USE_LPM) {
                data_reg = MIPI_LP_GEN_DATA(port);
                data_mask = LP_DATA_FIFO_FULL;
                ctrl_reg = MIPI_LP_GEN_CTRL(port);
                ctrl_mask = LP_CTRL_FIFO_FULL;
        } else {
                data_reg = MIPI_HS_GEN_DATA(port);
                data_mask = HS_DATA_FIFO_FULL;
                ctrl_reg = MIPI_HS_GEN_CTRL(port);
                ctrl_mask = HS_CTRL_FIFO_FULL;
        }

        /* note: this is never true for reads */
        if (packet.payload_length) {
                if (intel_wait_for_register(&dev_priv->uncore,
                                            MIPI_GEN_FIFO_STAT(port),
                                            data_mask, 0,
                                            50))
                        DRM_ERROR("Timeout waiting for HS/LP DATA FIFO !full\n");

                write_data(dev_priv, data_reg, packet.payload,
                           packet.payload_length);
        }

        if (msg->rx_len) {
                I915_WRITE(MIPI_INTR_STAT(port), GEN_READ_DATA_AVAIL);
        }

        if (intel_wait_for_register(&dev_priv->uncore,
                                    MIPI_GEN_FIFO_STAT(port),
                                    ctrl_mask, 0,
                                    50)) {
                DRM_ERROR("Timeout waiting for HS/LP CTRL FIFO !full\n");
        }

        I915_WRITE(ctrl_reg, header[2] << 16 | header[1] << 8 | header[0]);

        /* ->rx_len is set only for reads */
        if (msg->rx_len) {
                data_mask = GEN_READ_DATA_AVAIL;
                if (intel_wait_for_register(&dev_priv->uncore,
                                            MIPI_INTR_STAT(port),
                                            data_mask, data_mask,
                                            50))
                        DRM_ERROR("Timeout waiting for read data.\n");

                read_data(dev_priv, data_reg, msg->rx_buf, msg->rx_len);
        }

        /* XXX: fix for reads and writes */
        return 4 + packet.payload_length;
}

static int intel_dsi_host_attach(struct mipi_dsi_host *host,
                                 struct mipi_dsi_device *dsi)
{
        return 0;
}

static int intel_dsi_host_detach(struct mipi_dsi_host *host,
                                 struct mipi_dsi_device *dsi)
{
        return 0;
}

static const struct mipi_dsi_host_ops intel_dsi_host_ops = {
        .attach = intel_dsi_host_attach,
        .detach = intel_dsi_host_detach,
        .transfer = intel_dsi_host_transfer,
};

/*
 * send a video mode command
 *
 * XXX: commands with data in MIPI_DPI_DATA?
 */
static int dpi_send_cmd(struct intel_dsi *intel_dsi, u32 cmd, bool hs,
                        enum port port)
{
        struct drm_encoder *encoder = &intel_dsi->base.base;
        struct drm_device *dev = encoder->dev;
        struct drm_i915_private *dev_priv = to_i915(dev);
        u32 mask;

        /* XXX: pipe, hs */
        if (hs)
                cmd &= ~DPI_LP_MODE;
        else
                cmd |= DPI_LP_MODE;

        /* clear bit */
        I915_WRITE(MIPI_INTR_STAT(port), SPL_PKT_SENT_INTERRUPT);

        /* XXX: old code skips write if control unchanged */
        if (cmd == I915_READ(MIPI_DPI_CONTROL(port)))
                DRM_DEBUG_KMS("Same special packet %02x twice in a row.\n", cmd);

        I915_WRITE(MIPI_DPI_CONTROL(port), cmd);

        mask = SPL_PKT_SENT_INTERRUPT;
        if (intel_wait_for_register(&dev_priv->uncore,
                                    MIPI_INTR_STAT(port), mask, mask,
                                    100))
                DRM_ERROR("Video mode command 0x%08x send failed.\n", cmd);

        return 0;
}

static void band_gap_reset(struct drm_i915_private *dev_priv)
{
        vlv_flisdsi_get(dev_priv);

        vlv_flisdsi_write(dev_priv, 0x08, 0x0001);
        vlv_flisdsi_write(dev_priv, 0x0F, 0x0005);
        vlv_flisdsi_write(dev_priv, 0x0F, 0x0025);
        udelay(150);
        vlv_flisdsi_write(dev_priv, 0x0F, 0x0000);
        vlv_flisdsi_write(dev_priv, 0x08, 0x0000);

        vlv_flisdsi_put(dev_priv);
}

static int intel_dsi_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_dsi *intel_dsi = container_of(encoder, struct intel_dsi,
                                                   base);
        struct intel_connector *intel_connector = intel_dsi->attached_connector;
        struct intel_crtc *crtc = to_intel_crtc(pipe_config->base.crtc);
        const struct drm_display_mode *fixed_mode = intel_connector->panel.fixed_mode;
        struct drm_display_mode *adjusted_mode = &pipe_config->base.adjusted_mode;
        int ret;

        DRM_DEBUG_KMS("\n");
        pipe_config->output_format = INTEL_OUTPUT_FORMAT_RGB;

        if (fixed_mode) {
                intel_fixed_panel_mode(fixed_mode, adjusted_mode);

                if (HAS_GMCH(dev_priv))
                        intel_gmch_panel_fitting(crtc, pipe_config,
                                                 conn_state->scaling_mode);
                else
                        intel_pch_panel_fitting(crtc, pipe_config,
                                                conn_state->scaling_mode);
        }

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

        /* DSI uses short packets for sync events, so clear mode flags for DSI */
        adjusted_mode->flags = 0;

        if (intel_dsi->pixel_format == MIPI_DSI_FMT_RGB888)
                pipe_config->pipe_bpp = 24;
        else
                pipe_config->pipe_bpp = 18;

        if (IS_GEN9_LP(dev_priv)) {
                /* Enable Frame time stamp based scanline reporting */
                adjusted_mode->private_flags |=
                        I915_MODE_FLAG_GET_SCANLINE_FROM_TIMESTAMP;

                /* Dual link goes to DSI transcoder A. */
                if (intel_dsi->ports == BIT(PORT_C))
                        pipe_config->cpu_transcoder = TRANSCODER_DSI_C;
                else
                        pipe_config->cpu_transcoder = TRANSCODER_DSI_A;

                ret = bxt_dsi_pll_compute(encoder, pipe_config);
                if (ret)
                        return -EINVAL;
        } else {
                ret = vlv_dsi_pll_compute(encoder, pipe_config);
                if (ret)
                        return -EINVAL;
        }

        pipe_config->clock_set = true;

        return 0;
}

static bool glk_dsi_enable_io(struct intel_encoder *encoder)
{
        struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
        struct intel_dsi *intel_dsi = enc_to_intel_dsi(&encoder->base);
        enum port port;
        u32 tmp;
        bool cold_boot = false;

        /* Set the MIPI mode
         * If MIPI_Mode is off, then writing to LP_Wake bit is not reflecting.
         * Power ON MIPI IO first and then write into IO reset and LP wake bits
         */
        for_each_dsi_port(port, intel_dsi->ports) {
                tmp = I915_READ(MIPI_CTRL(port));
                I915_WRITE(MIPI_CTRL(port), tmp | GLK_MIPIIO_ENABLE);
        }

        /* Put the IO into reset */
        tmp = I915_READ(MIPI_CTRL(PORT_A));
        tmp &= ~GLK_MIPIIO_RESET_RELEASED;
        I915_WRITE(MIPI_CTRL(PORT_A), tmp);

        /* Program LP Wake */
        for_each_dsi_port(port, intel_dsi->ports) {
                tmp = I915_READ(MIPI_CTRL(port));
                if (!(I915_READ(MIPI_DEVICE_READY(port)) & DEVICE_READY))
                        tmp &= ~GLK_LP_WAKE;
                else
                        tmp |= GLK_LP_WAKE;
                I915_WRITE(MIPI_CTRL(port), tmp);
        }

        /* Wait for Pwr ACK */
        for_each_dsi_port(port, intel_dsi->ports) {
                if (intel_wait_for_register(&dev_priv->uncore,
                                            MIPI_CTRL(port),
                                            GLK_MIPIIO_PORT_POWERED,
                                            GLK_MIPIIO_PORT_POWERED,
                                            20))
                        DRM_ERROR("MIPIO port is powergated\n");
        }

        /* Check for cold boot scenario */
        for_each_dsi_port(port, intel_dsi->ports) {
                cold_boot |=
                        !(I915_READ(MIPI_DEVICE_READY(port)) & DEVICE_READY);
        }

        return cold_boot;
}

static void glk_dsi_device_ready(struct intel_encoder *encoder)
{
        struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
        struct intel_dsi *intel_dsi = enc_to_intel_dsi(&encoder->base);
        enum port port;
        u32 val;

        /* Wait for MIPI PHY status bit to set */
        for_each_dsi_port(port, intel_dsi->ports) {
                if (intel_wait_for_register(&dev_priv->uncore,
                                            MIPI_CTRL(port),
                                            GLK_PHY_STATUS_PORT_READY,
                                            GLK_PHY_STATUS_PORT_READY,
                                            20))
                        DRM_ERROR("PHY is not ON\n");
        }

        /* Get IO out of reset */
        val = I915_READ(MIPI_CTRL(PORT_A));
        I915_WRITE(MIPI_CTRL(PORT_A), val | GLK_MIPIIO_RESET_RELEASED);

        /* Get IO out of Low power state*/
        for_each_dsi_port(port, intel_dsi->ports) {
                if (!(I915_READ(MIPI_DEVICE_READY(port)) & DEVICE_READY)) {
                        val = I915_READ(MIPI_DEVICE_READY(port));
                        val &= ~ULPS_STATE_MASK;
                        val |= DEVICE_READY;
                        I915_WRITE(MIPI_DEVICE_READY(port), val);
                        usleep_range(10, 15);
                } else {
                        /* Enter ULPS */
                        val = I915_READ(MIPI_DEVICE_READY(port));
                        val &= ~ULPS_STATE_MASK;
                        val |= (ULPS_STATE_ENTER | DEVICE_READY);
                        I915_WRITE(MIPI_DEVICE_READY(port), val);

                        /* Wait for ULPS active */
                        if (intel_wait_for_register(&dev_priv->uncore,
                                                    MIPI_CTRL(port),
                                                    GLK_ULPS_NOT_ACTIVE,
                                                    0,
                                                    20))
                                DRM_ERROR("ULPS not active\n");

                        /* Exit ULPS */
                        val = I915_READ(MIPI_DEVICE_READY(port));
                        val &= ~ULPS_STATE_MASK;
                        val |= (ULPS_STATE_EXIT | DEVICE_READY);
                        I915_WRITE(MIPI_DEVICE_READY(port), val);

                        /* Enter Normal Mode */
                        val = I915_READ(MIPI_DEVICE_READY(port));
                        val &= ~ULPS_STATE_MASK;
                        val |= (ULPS_STATE_NORMAL_OPERATION | DEVICE_READY);
                        I915_WRITE(MIPI_DEVICE_READY(port), val);

                        val = I915_READ(MIPI_CTRL(port));
                        val &= ~GLK_LP_WAKE;
                        I915_WRITE(MIPI_CTRL(port), val);
                }
        }

        /* Wait for Stop state */
        for_each_dsi_port(port, intel_dsi->ports) {
                if (intel_wait_for_register(&dev_priv->uncore,
                                            MIPI_CTRL(port),
                                            GLK_DATA_LANE_STOP_STATE,
                                            GLK_DATA_LANE_STOP_STATE,
                                            20))
                        DRM_ERROR("Date lane not in STOP state\n");
        }

        /* Wait for AFE LATCH */
        for_each_dsi_port(port, intel_dsi->ports) {
                if (intel_wait_for_register(&dev_priv->uncore,
                                            BXT_MIPI_PORT_CTRL(port),
                                            AFE_LATCHOUT,
                                            AFE_LATCHOUT,
                                            20))
                        DRM_ERROR("D-PHY not entering LP-11 state\n");
        }
}

static void bxt_dsi_device_ready(struct intel_encoder *encoder)
{
        struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
        struct intel_dsi *intel_dsi = enc_to_intel_dsi(&encoder->base);
        enum port port;
        u32 val;

        DRM_DEBUG_KMS("\n");

        /* Enable MIPI PHY transparent latch */
        for_each_dsi_port(port, intel_dsi->ports) {
                val = I915_READ(BXT_MIPI_PORT_CTRL(port));
                I915_WRITE(BXT_MIPI_PORT_CTRL(port), val | LP_OUTPUT_HOLD);
                usleep_range(2000, 2500);
        }

        /* Clear ULPS and set device ready */
        for_each_dsi_port(port, intel_dsi->ports) {
                val = I915_READ(MIPI_DEVICE_READY(port));
                val &= ~ULPS_STATE_MASK;
                I915_WRITE(MIPI_DEVICE_READY(port), val);
                usleep_range(2000, 2500);
                val |= DEVICE_READY;
                I915_WRITE(MIPI_DEVICE_READY(port), val);
        }
}

static void vlv_dsi_device_ready(struct intel_encoder *encoder)
{
        struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
        struct intel_dsi *intel_dsi = enc_to_intel_dsi(&encoder->base);
        enum port port;
        u32 val;

        DRM_DEBUG_KMS("\n");

        vlv_flisdsi_get(dev_priv);
        /* program rcomp for compliance, reduce from 50 ohms to 45 ohms
         * needed everytime after power gate */
        vlv_flisdsi_write(dev_priv, 0x04, 0x0004);
        vlv_flisdsi_put(dev_priv);

        /* bandgap reset is needed after everytime we do power gate */
        band_gap_reset(dev_priv);

        for_each_dsi_port(port, intel_dsi->ports) {

                I915_WRITE(MIPI_DEVICE_READY(port), ULPS_STATE_ENTER);
                usleep_range(2500, 3000);

                /* Enable MIPI PHY transparent latch
                 * Common bit for both MIPI Port A & MIPI Port C
                 * No similar bit in MIPI Port C reg
                 */
                val = I915_READ(MIPI_PORT_CTRL(PORT_A));
                I915_WRITE(MIPI_PORT_CTRL(PORT_A), val | LP_OUTPUT_HOLD);
                usleep_range(1000, 1500);

                I915_WRITE(MIPI_DEVICE_READY(port), ULPS_STATE_EXIT);
                usleep_range(2500, 3000);

                I915_WRITE(MIPI_DEVICE_READY(port), DEVICE_READY);
                usleep_range(2500, 3000);
        }
}

static void intel_dsi_device_ready(struct intel_encoder *encoder)
{
        struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);

        if (IS_GEMINILAKE(dev_priv))
                glk_dsi_device_ready(encoder);
        else if (IS_GEN9_LP(dev_priv))
                bxt_dsi_device_ready(encoder);
        else
                vlv_dsi_device_ready(encoder);
}

static void glk_dsi_enter_low_power_mode(struct intel_encoder *encoder)
{
        struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
        struct intel_dsi *intel_dsi = enc_to_intel_dsi(&encoder->base);
        enum port port;
        u32 val;

        /* Enter ULPS */
        for_each_dsi_port(port, intel_dsi->ports) {
                val = I915_READ(MIPI_DEVICE_READY(port));
                val &= ~ULPS_STATE_MASK;
                val |= (ULPS_STATE_ENTER | DEVICE_READY);
                I915_WRITE(MIPI_DEVICE_READY(port), val);
        }

        /* Wait for MIPI PHY status bit to unset */
        for_each_dsi_port(port, intel_dsi->ports) {
                if (intel_wait_for_register(&dev_priv->uncore,
                                            MIPI_CTRL(port),
                                            GLK_PHY_STATUS_PORT_READY, 0, 20))
                        DRM_ERROR("PHY is not turning OFF\n");
        }

        /* Wait for Pwr ACK bit to unset */
        for_each_dsi_port(port, intel_dsi->ports) {
                if (intel_wait_for_register(&dev_priv->uncore,
                                            MIPI_CTRL(port),
                                            GLK_MIPIIO_PORT_POWERED, 0, 20))
                        DRM_ERROR("MIPI IO Port is not powergated\n");
        }
}

static void glk_dsi_disable_mipi_io(struct intel_encoder *encoder)
{
        struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
        struct intel_dsi *intel_dsi = enc_to_intel_dsi(&encoder->base);
        enum port port;
        u32 tmp;

        /* Put the IO into reset */
        tmp = I915_READ(MIPI_CTRL(PORT_A));
        tmp &= ~GLK_MIPIIO_RESET_RELEASED;
        I915_WRITE(MIPI_CTRL(PORT_A), tmp);

        /* Wait for MIPI PHY status bit to unset */
        for_each_dsi_port(port, intel_dsi->ports) {
                if (intel_wait_for_register(&dev_priv->uncore,
                                            MIPI_CTRL(port),
                                            GLK_PHY_STATUS_PORT_READY, 0, 20))
                        DRM_ERROR("PHY is not turning OFF\n");
        }

        /* Clear MIPI mode */
        for_each_dsi_port(port, intel_dsi->ports) {
                tmp = I915_READ(MIPI_CTRL(port));
                tmp &= ~GLK_MIPIIO_ENABLE;
                I915_WRITE(MIPI_CTRL(port), tmp);
        }
}

static void glk_dsi_clear_device_ready(struct intel_encoder *encoder)
{
        glk_dsi_enter_low_power_mode(encoder);
        glk_dsi_disable_mipi_io(encoder);
}

static void vlv_dsi_clear_device_ready(struct intel_encoder *encoder)
{
        struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
        struct intel_dsi *intel_dsi = enc_to_intel_dsi(&encoder->base);
        enum port port;

        DRM_DEBUG_KMS("\n");
        for_each_dsi_port(port, intel_dsi->ports) {
                /* Common bit for both MIPI Port A & MIPI Port C on VLV/CHV */
                i915_reg_t port_ctrl = IS_GEN9_LP(dev_priv) ?
                        BXT_MIPI_PORT_CTRL(port) : MIPI_PORT_CTRL(PORT_A);
                u32 val;

                I915_WRITE(MIPI_DEVICE_READY(port), DEVICE_READY |
                                                        ULPS_STATE_ENTER);
                usleep_range(2000, 2500);

                I915_WRITE(MIPI_DEVICE_READY(port), DEVICE_READY |
                                                        ULPS_STATE_EXIT);
                usleep_range(2000, 2500);

                I915_WRITE(MIPI_DEVICE_READY(port), DEVICE_READY |
                                                        ULPS_STATE_ENTER);
                usleep_range(2000, 2500);

                /*
                 * On VLV/CHV, wait till Clock lanes are in LP-00 state for MIPI
                 * Port A only. MIPI Port C has no similar bit for checking.
                 */
                if ((IS_GEN9_LP(dev_priv) || port == PORT_A) &&
                    intel_wait_for_register(&dev_priv->uncore,
                                            port_ctrl, AFE_LATCHOUT, 0,
                                            30))
                        DRM_ERROR("DSI LP not going Low\n");

                /* Disable MIPI PHY transparent latch */
                val = I915_READ(port_ctrl);
                I915_WRITE(port_ctrl, val & ~LP_OUTPUT_HOLD);
                usleep_range(1000, 1500);

                I915_WRITE(MIPI_DEVICE_READY(port), 0x00);
                usleep_range(2000, 2500);
        }
}

static void intel_dsi_port_enable(struct intel_encoder *encoder,
                                  const struct intel_crtc_state *crtc_state)
{
        struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
        struct intel_crtc *crtc = to_intel_crtc(crtc_state->base.crtc);
        struct intel_dsi *intel_dsi = enc_to_intel_dsi(&encoder->base);
        enum port port;

        if (intel_dsi->dual_link == DSI_DUAL_LINK_FRONT_BACK) {
                u32 temp;
                if (IS_GEN9_LP(dev_priv)) {
                        for_each_dsi_port(port, intel_dsi->ports) {
                                temp = I915_READ(MIPI_CTRL(port));
                                temp &= ~BXT_PIXEL_OVERLAP_CNT_MASK |
                                        intel_dsi->pixel_overlap <<
                                        BXT_PIXEL_OVERLAP_CNT_SHIFT;
                                I915_WRITE(MIPI_CTRL(port), temp);
                        }
                } else {
                        temp = I915_READ(VLV_CHICKEN_3);
                        temp &= ~PIXEL_OVERLAP_CNT_MASK |
                                        intel_dsi->pixel_overlap <<
                                        PIXEL_OVERLAP_CNT_SHIFT;
                        I915_WRITE(VLV_CHICKEN_3, temp);
                }
        }

        for_each_dsi_port(port, intel_dsi->ports) {
                i915_reg_t port_ctrl = IS_GEN9_LP(dev_priv) ?
                        BXT_MIPI_PORT_CTRL(port) : MIPI_PORT_CTRL(port);
                u32 temp;

                temp = I915_READ(port_ctrl);

                temp &= ~LANE_CONFIGURATION_MASK;
                temp &= ~DUAL_LINK_MODE_MASK;

                if (intel_dsi->ports == (BIT(PORT_A) | BIT(PORT_C))) {
                        temp |= (intel_dsi->dual_link - 1)
                                                << DUAL_LINK_MODE_SHIFT;
                        if (IS_BROXTON(dev_priv))
                                temp |= LANE_CONFIGURATION_DUAL_LINK_A;
                        else
                                temp |= crtc->pipe ?
                                        LANE_CONFIGURATION_DUAL_LINK_B :
                                        LANE_CONFIGURATION_DUAL_LINK_A;
                }

                if (intel_dsi->pixel_format != MIPI_DSI_FMT_RGB888)
                        temp |= DITHERING_ENABLE;

                /* assert ip_tg_enable signal */
                I915_WRITE(port_ctrl, temp | DPI_ENABLE);
                POSTING_READ(port_ctrl);
        }
}

static void intel_dsi_port_disable(struct intel_encoder *encoder)
{
        struct drm_device *dev = encoder->base.dev;
        struct drm_i915_private *dev_priv = to_i915(dev);
        struct intel_dsi *intel_dsi = enc_to_intel_dsi(&encoder->base);
        enum port port;

        for_each_dsi_port(port, intel_dsi->ports) {
                i915_reg_t port_ctrl = IS_GEN9_LP(dev_priv) ?
                        BXT_MIPI_PORT_CTRL(port) : MIPI_PORT_CTRL(port);
                u32 temp;

                /* de-assert ip_tg_enable signal */
                temp = I915_READ(port_ctrl);
                I915_WRITE(port_ctrl, temp & ~DPI_ENABLE);
                POSTING_READ(port_ctrl);
        }
}

static void intel_dsi_prepare(struct intel_encoder *intel_encoder,
                              const struct intel_crtc_state *pipe_config);
static void intel_dsi_unprepare(struct intel_encoder *encoder);

/*
 * Panel enable/disable sequences from the VBT spec.
 *
 * Note the spec has AssertReset / DeassertReset swapped from their
 * usual naming. We use the normal names to avoid confusion (so below
 * they are swapped compared to the spec).
 *
 * Steps starting with MIPI refer to VBT sequences, note that for v2
 * VBTs several steps which have a VBT in v2 are expected to be handled
 * directly by the driver, by directly driving gpios for example.
 *
 * v2 video mode seq         v3 video mode seq         command mode seq
 * - power on                - MIPIPanelPowerOn        - power on
 * - wait t1+t2                                        - wait t1+t2
 * - MIPIDeassertResetPin    - MIPIDeassertResetPin    - MIPIDeassertResetPin
 * - io lines to lp-11       - io lines to lp-11       - io lines to lp-11
 * - MIPISendInitialDcsCmds  - MIPISendInitialDcsCmds  - MIPISendInitialDcsCmds
 *                                                     - MIPITearOn
 *                                                     - MIPIDisplayOn
 * - turn on DPI             - turn on DPI             - set pipe to dsr mode
 * - MIPIDisplayOn           - MIPIDisplayOn
 * - wait t5                                           - wait t5
 * - backlight on            - MIPIBacklightOn         - backlight on
 * ...                       ...                       ... issue mem cmds ...
 * - backlight off           - MIPIBacklightOff        - backlight off
 * - wait t6                                           - wait t6
 * - MIPIDisplayOff
 * - turn off DPI            - turn off DPI            - disable pipe dsr mode
 *                                                     - MIPITearOff
 *                           - MIPIDisplayOff          - MIPIDisplayOff
 * - io lines to lp-00       - io lines to lp-00       - io lines to lp-00
 * - MIPIAssertResetPin      - MIPIAssertResetPin      - MIPIAssertResetPin
 * - wait t3                                           - wait t3
 * - power off               - MIPIPanelPowerOff       - power off
 * - wait t4                                           - wait t4
 */

/*
 * DSI port enable has to be done before pipe and plane enable, so we do it in
 * the pre_enable hook instead of the enable hook.
 */
static void intel_dsi_pre_enable(struct intel_encoder *encoder,
                                 const struct intel_crtc_state *pipe_config,
                                 const struct drm_connector_state *conn_state)
{
        struct intel_dsi *intel_dsi = enc_to_intel_dsi(&encoder->base);
        struct drm_crtc *crtc = pipe_config->base.crtc;
        struct drm_i915_private *dev_priv = to_i915(crtc->dev);
        struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
        int pipe = intel_crtc->pipe;
        enum port port;
        u32 val;
        bool glk_cold_boot = false;

        DRM_DEBUG_KMS("\n");

        intel_set_cpu_fifo_underrun_reporting(dev_priv, pipe, true);

        /*
         * The BIOS may leave the PLL in a wonky state where it doesn't
         * lock. It needs to be fully powered down to fix it.
         */
        if (IS_GEN9_LP(dev_priv)) {
                bxt_dsi_pll_disable(encoder);
                bxt_dsi_pll_enable(encoder, pipe_config);
        } else {
                vlv_dsi_pll_disable(encoder);
                vlv_dsi_pll_enable(encoder, pipe_config);
        }

        if (IS_BROXTON(dev_priv)) {
                /* Add MIPI IO reset programming for modeset */
                val = I915_READ(BXT_P_CR_GT_DISP_PWRON);
                I915_WRITE(BXT_P_CR_GT_DISP_PWRON,
                                        val | MIPIO_RST_CTRL);

                /* Power up DSI regulator */
                I915_WRITE(BXT_P_DSI_REGULATOR_CFG, STAP_SELECT);
                I915_WRITE(BXT_P_DSI_REGULATOR_TX_CTRL, 0);
        }

        if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv)) {
                u32 val;

                /* Disable DPOunit clock gating, can stall pipe */
                val = I915_READ(DSPCLK_GATE_D);
                val |= DPOUNIT_CLOCK_GATE_DISABLE;
                I915_WRITE(DSPCLK_GATE_D, val);
        }

        if (!IS_GEMINILAKE(dev_priv))
                intel_dsi_prepare(encoder, pipe_config);

        /* Power on, try both CRC pmic gpio and VBT */
        if (intel_dsi->gpio_panel)
                gpiod_set_value_cansleep(intel_dsi->gpio_panel, 1);
        intel_dsi_vbt_exec_sequence(intel_dsi, MIPI_SEQ_POWER_ON);
        intel_dsi_msleep(intel_dsi, intel_dsi->panel_on_delay);

        /* Deassert reset */
        intel_dsi_vbt_exec_sequence(intel_dsi, MIPI_SEQ_DEASSERT_RESET);

        if (IS_GEMINILAKE(dev_priv)) {
                glk_cold_boot = glk_dsi_enable_io(encoder);

                /* Prepare port in cold boot(s3/s4) scenario */
                if (glk_cold_boot)
                        intel_dsi_prepare(encoder, pipe_config);
        }

        /* Put device in ready state (LP-11) */
        intel_dsi_device_ready(encoder);

        /* Prepare port in normal boot scenario */
        if (IS_GEMINILAKE(dev_priv) && !glk_cold_boot)
                intel_dsi_prepare(encoder, pipe_config);

        /* Send initialization commands in LP mode */
        intel_dsi_vbt_exec_sequence(intel_dsi, MIPI_SEQ_INIT_OTP);

        /* Enable port in pre-enable phase itself because as per hw team
         * recommendation, port should be enabled befor plane & pipe */
        if (is_cmd_mode(intel_dsi)) {
                for_each_dsi_port(port, intel_dsi->ports)
                        I915_WRITE(MIPI_MAX_RETURN_PKT_SIZE(port), 8 * 4);
                intel_dsi_vbt_exec_sequence(intel_dsi, MIPI_SEQ_TEAR_ON);
                intel_dsi_vbt_exec_sequence(intel_dsi, MIPI_SEQ_DISPLAY_ON);
        } else {
                msleep(20); /* XXX */
                for_each_dsi_port(port, intel_dsi->ports)
                        dpi_send_cmd(intel_dsi, TURN_ON, false, port);
                intel_dsi_msleep(intel_dsi, 100);

                intel_dsi_vbt_exec_sequence(intel_dsi, MIPI_SEQ_DISPLAY_ON);

                intel_dsi_port_enable(encoder, pipe_config);
        }

        intel_panel_enable_backlight(pipe_config, conn_state);
        intel_dsi_vbt_exec_sequence(intel_dsi, MIPI_SEQ_BACKLIGHT_ON);
}

/*
 * DSI port disable has to be done after pipe and plane disable, so we do it in
 * the post_disable hook.
 */
static void intel_dsi_disable(struct intel_encoder *encoder,
                              const struct intel_crtc_state *old_crtc_state,
                              const struct drm_connector_state *old_conn_state)
{
        struct intel_dsi *intel_dsi = enc_to_intel_dsi(&encoder->base);
        enum port port;

        DRM_DEBUG_KMS("\n");

        intel_dsi_vbt_exec_sequence(intel_dsi, MIPI_SEQ_BACKLIGHT_OFF);
        intel_panel_disable_backlight(old_conn_state);

        /*
         * According to the spec we should send SHUTDOWN before
         * MIPI_SEQ_DISPLAY_OFF only for v3+ VBTs, but field testing
         * has shown that the v3 sequence works for v2 VBTs too
         */
        if (is_vid_mode(intel_dsi)) {
                /* Send Shutdown command to the panel in LP mode */
                for_each_dsi_port(port, intel_dsi->ports)
                        dpi_send_cmd(intel_dsi, SHUTDOWN, false, port);
                msleep(10);
        }
}

static void intel_dsi_clear_device_ready(struct intel_encoder *encoder)
{
        struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);

        if (IS_GEMINILAKE(dev_priv))
                glk_dsi_clear_device_ready(encoder);
        else
                vlv_dsi_clear_device_ready(encoder);
}

static void intel_dsi_post_disable(struct intel_encoder *encoder,
                                   const struct intel_crtc_state *pipe_config,
                                   const struct drm_connector_state *conn_state)
{
        struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
        struct intel_dsi *intel_dsi = enc_to_intel_dsi(&encoder->base);
        enum port port;
        u32 val;

        DRM_DEBUG_KMS("\n");

        if (is_vid_mode(intel_dsi)) {
                for_each_dsi_port(port, intel_dsi->ports)
                        vlv_dsi_wait_for_fifo_empty(intel_dsi, port);

                intel_dsi_port_disable(encoder);
                usleep_range(2000, 5000);
        }

        intel_dsi_unprepare(encoder);

        /*
         * if disable packets are sent before sending shutdown packet then in
         * some next enable sequence send turn on packet error is observed
         */
        if (is_cmd_mode(intel_dsi))
                intel_dsi_vbt_exec_sequence(intel_dsi, MIPI_SEQ_TEAR_OFF);
        intel_dsi_vbt_exec_sequence(intel_dsi, MIPI_SEQ_DISPLAY_OFF);

        /* Transition to LP-00 */
        intel_dsi_clear_device_ready(encoder);

        if (IS_BROXTON(dev_priv)) {
                /* Power down DSI regulator to save power */
                I915_WRITE(BXT_P_DSI_REGULATOR_CFG, STAP_SELECT);
                I915_WRITE(BXT_P_DSI_REGULATOR_TX_CTRL, HS_IO_CTRL_SELECT);

                /* Add MIPI IO reset programming for modeset */
                val = I915_READ(BXT_P_CR_GT_DISP_PWRON);
                I915_WRITE(BXT_P_CR_GT_DISP_PWRON,
                                val & ~MIPIO_RST_CTRL);
        }

        if (IS_GEN9_LP(dev_priv)) {
                bxt_dsi_pll_disable(encoder);
        } else {
                u32 val;

                vlv_dsi_pll_disable(encoder);

                val = I915_READ(DSPCLK_GATE_D);
                val &= ~DPOUNIT_CLOCK_GATE_DISABLE;
                I915_WRITE(DSPCLK_GATE_D, val);
        }

        /* Assert reset */
        intel_dsi_vbt_exec_sequence(intel_dsi, MIPI_SEQ_ASSERT_RESET);

        /* Power off, try both CRC pmic gpio and VBT */
        intel_dsi_msleep(intel_dsi, intel_dsi->panel_off_delay);
        intel_dsi_vbt_exec_sequence(intel_dsi, MIPI_SEQ_POWER_OFF);
        if (intel_dsi->gpio_panel)
                gpiod_set_value_cansleep(intel_dsi->gpio_panel, 0);

        /*
         * FIXME As we do with eDP, just make a note of the time here
         * and perform the wait before the next panel power on.
         */
        intel_dsi_msleep(intel_dsi, intel_dsi->panel_pwr_cycle_delay);
}

static bool intel_dsi_get_hw_state(struct intel_encoder *encoder,
                                   enum pipe *pipe)
{
        struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
        struct intel_dsi *intel_dsi = enc_to_intel_dsi(&encoder->base);
        intel_wakeref_t wakeref;
        enum port port;
        bool active = false;

        DRM_DEBUG_KMS("\n");

        wakeref = intel_display_power_get_if_enabled(dev_priv,
                                                     encoder->power_domain);
        if (!wakeref)
                return false;

        /*
         * On Broxton the PLL needs to be enabled with a valid divider

         * configuration, otherwise accessing DSI registers will hang the
         * machine. See BSpec North Display Engine registers/MIPI[BXT].
         */
        if (IS_GEN9_LP(dev_priv) && !bxt_dsi_pll_is_enabled(dev_priv))
                goto out_put_power;

        /* XXX: this only works for one DSI output */
        for_each_dsi_port(port, intel_dsi->ports) {
                i915_reg_t ctrl_reg = IS_GEN9_LP(dev_priv) ?
                        BXT_MIPI_PORT_CTRL(port) : MIPI_PORT_CTRL(port);
                bool enabled = I915_READ(ctrl_reg) & DPI_ENABLE;

                /*
                 * Due to some hardware limitations on VLV/CHV, the DPI enable
                 * bit in port C control register does not get set. As a
                 * workaround, check pipe B conf instead.
                 */
                if ((IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv)) &&
                    port == PORT_C)
                        enabled = I915_READ(PIPECONF(PIPE_B)) & PIPECONF_ENABLE;

                /* Try command mode if video mode not enabled */
                if (!enabled) {
                        u32 tmp = I915_READ(MIPI_DSI_FUNC_PRG(port));
                        enabled = tmp & CMD_MODE_DATA_WIDTH_MASK;
                }

                if (!enabled)
                        continue;

                if (!(I915_READ(MIPI_DEVICE_READY(port)) & DEVICE_READY))
                        continue;

                if (IS_GEN9_LP(dev_priv)) {
                        u32 tmp = I915_READ(MIPI_CTRL(port));
                        tmp &= BXT_PIPE_SELECT_MASK;
                        tmp >>= BXT_PIPE_SELECT_SHIFT;

                        if (WARN_ON(tmp > PIPE_C))
                                continue;

                        *pipe = tmp;
                } else {
                        *pipe = port == PORT_A ? PIPE_A : PIPE_B;
                }

                active = true;
                break;
        }

out_put_power:
        intel_display_power_put(dev_priv, encoder->power_domain, wakeref);

        return active;
}

static void bxt_dsi_get_pipe_config(struct intel_encoder *encoder,
                                    struct intel_crtc_state *pipe_config)
{
        struct drm_device *dev = encoder->base.dev;
        struct drm_i915_private *dev_priv = to_i915(dev);
        struct drm_display_mode *adjusted_mode =
                                        &pipe_config->base.adjusted_mode;
        struct drm_display_mode *adjusted_mode_sw;
        struct intel_crtc *crtc = to_intel_crtc(pipe_config->base.crtc);
        struct intel_dsi *intel_dsi = enc_to_intel_dsi(&encoder->base);
        unsigned int lane_count = intel_dsi->lane_count;
        unsigned int bpp, fmt;
        enum port port;
        u16 hactive, hfp, hsync, hbp, vfp, vsync, vbp;
        u16 hfp_sw, hsync_sw, hbp_sw;
        u16 crtc_htotal_sw, crtc_hsync_start_sw, crtc_hsync_end_sw,
                                crtc_hblank_start_sw, crtc_hblank_end_sw;

        /* FIXME: hw readout should not depend on SW state */
        adjusted_mode_sw = &crtc->config->base.adjusted_mode;

        /*
         * Atleast one port is active as encoder->get_config called only if
         * encoder->get_hw_state() returns true.
         */
        for_each_dsi_port(port, intel_dsi->ports) {
                if (I915_READ(BXT_MIPI_PORT_CTRL(port)) & DPI_ENABLE)
                        break;
        }

        fmt = I915_READ(MIPI_DSI_FUNC_PRG(port)) & VID_MODE_FORMAT_MASK;
        bpp = mipi_dsi_pixel_format_to_bpp(
                        pixel_format_from_register_bits(fmt));

        pipe_config->pipe_bpp = bdw_get_pipemisc_bpp(crtc);

        /* Enable Frame time stamo based scanline reporting */
        adjusted_mode->private_flags |=
                        I915_MODE_FLAG_GET_SCANLINE_FROM_TIMESTAMP;

        /* In terms of pixels */
        adjusted_mode->crtc_hdisplay =
                                I915_READ(BXT_MIPI_TRANS_HACTIVE(port));
        adjusted_mode->crtc_vdisplay =
                                I915_READ(BXT_MIPI_TRANS_VACTIVE(port));
        adjusted_mode->crtc_vtotal =
                                I915_READ(BXT_MIPI_TRANS_VTOTAL(port));

        hactive = adjusted_mode->crtc_hdisplay;
        hfp = I915_READ(MIPI_HFP_COUNT(port));

        /*
         * Meaningful for video mode non-burst sync pulse mode only,
         * can be zero for non-burst sync events and burst modes
         */
        hsync = I915_READ(MIPI_HSYNC_PADDING_COUNT(port));
        hbp = I915_READ(MIPI_HBP_COUNT(port));

        /* harizontal values are in terms of high speed byte clock */
        hfp = pixels_from_txbyteclkhs(hfp, bpp, lane_count,
                                                intel_dsi->burst_mode_ratio);
        hsync = pixels_from_txbyteclkhs(hsync, bpp, lane_count,
                                                intel_dsi->burst_mode_ratio);
        hbp = pixels_from_txbyteclkhs(hbp, bpp, lane_count,
                                                intel_dsi->burst_mode_ratio);

        if (intel_dsi->dual_link) {
                hfp *= 2;
                hsync *= 2;
                hbp *= 2;
        }

        /* vertical values are in terms of lines */
        vfp = I915_READ(MIPI_VFP_COUNT(port));
        vsync = I915_READ(MIPI_VSYNC_PADDING_COUNT(port));
        vbp = I915_READ(MIPI_VBP_COUNT(port));

        adjusted_mode->crtc_htotal = hactive + hfp + hsync + hbp;
        adjusted_mode->crtc_hsync_start = hfp + adjusted_mode->crtc_hdisplay;
        adjusted_mode->crtc_hsync_end = hsync + adjusted_mode->crtc_hsync_start;
        adjusted_mode->crtc_hblank_start = adjusted_mode->crtc_hdisplay;
        adjusted_mode->crtc_hblank_end = adjusted_mode->crtc_htotal;

        adjusted_mode->crtc_vsync_start = vfp + adjusted_mode->crtc_vdisplay;
        adjusted_mode->crtc_vsync_end = vsync + adjusted_mode->crtc_vsync_start;
        adjusted_mode->crtc_vblank_start = adjusted_mode->crtc_vdisplay;
        adjusted_mode->crtc_vblank_end = adjusted_mode->crtc_vtotal;

        /*
         * In BXT DSI there is no regs programmed with few horizontal timings
         * in Pixels but txbyteclkhs.. So retrieval process adds some
         * ROUND_UP ERRORS in the process of PIXELS<==>txbyteclkhs.
         * Actually here for the given adjusted_mode, we are calculating the
         * value programmed to the port and then back to the horizontal timing
         * param in pixels. This is the expected value, including roundup errors
         * And if that is same as retrieved value from port, then
         * (HW state) adjusted_mode's horizontal timings are corrected to
         * match with SW state to nullify the errors.
         */
        /* Calculating the value programmed to the Port register */
        hfp_sw = adjusted_mode_sw->crtc_hsync_start -
                                        adjusted_mode_sw->crtc_hdisplay;
        hsync_sw = adjusted_mode_sw->crtc_hsync_end -
                                        adjusted_mode_sw->crtc_hsync_start;
        hbp_sw = adjusted_mode_sw->crtc_htotal -
                                        adjusted_mode_sw->crtc_hsync_end;

        if (intel_dsi->dual_link) {
                hfp_sw /= 2;
                hsync_sw /= 2;
                hbp_sw /= 2;
        }

        hfp_sw = txbyteclkhs(hfp_sw, bpp, lane_count,
                                                intel_dsi->burst_mode_ratio);
        hsync_sw = txbyteclkhs(hsync_sw, bpp, lane_count,
                            intel_dsi->burst_mode_ratio);
        hbp_sw = txbyteclkhs(hbp_sw, bpp, lane_count,
                                                intel_dsi->burst_mode_ratio);

        /* Reverse calculating the adjusted mode parameters from port reg vals*/
        hfp_sw = pixels_from_txbyteclkhs(hfp_sw, bpp, lane_count,
                                                intel_dsi->burst_mode_ratio);
        hsync_sw = pixels_from_txbyteclkhs(hsync_sw, bpp, lane_count,
                                                intel_dsi->burst_mode_ratio);
        hbp_sw = pixels_from_txbyteclkhs(hbp_sw, bpp, lane_count,
                                                intel_dsi->burst_mode_ratio);

        if (intel_dsi->dual_link) {
                hfp_sw *= 2;
                hsync_sw *= 2;
                hbp_sw *= 2;
        }

        crtc_htotal_sw = adjusted_mode_sw->crtc_hdisplay + hfp_sw +
                                                        hsync_sw + hbp_sw;
        crtc_hsync_start_sw = hfp_sw + adjusted_mode_sw->crtc_hdisplay;
        crtc_hsync_end_sw = hsync_sw + crtc_hsync_start_sw;
        crtc_hblank_start_sw = adjusted_mode_sw->crtc_hdisplay;
        crtc_hblank_end_sw = crtc_htotal_sw;

        if (adjusted_mode->crtc_htotal == crtc_htotal_sw)
                adjusted_mode->crtc_htotal = adjusted_mode_sw->crtc_htotal;

        if (adjusted_mode->crtc_hsync_start == crtc_hsync_start_sw)
                adjusted_mode->crtc_hsync_start =
                                        adjusted_mode_sw->crtc_hsync_start;

        if (adjusted_mode->crtc_hsync_end == crtc_hsync_end_sw)
                adjusted_mode->crtc_hsync_end =
                                        adjusted_mode_sw->crtc_hsync_end;

        if (adjusted_mode->crtc_hblank_start == crtc_hblank_start_sw)
                adjusted_mode->crtc_hblank_start =
                                        adjusted_mode_sw->crtc_hblank_start;

        if (adjusted_mode->crtc_hblank_end == crtc_hblank_end_sw)
                adjusted_mode->crtc_hblank_end =
                                        adjusted_mode_sw->crtc_hblank_end;
}

static void intel_dsi_get_config(struct intel_encoder *encoder,
                                 struct intel_crtc_state *pipe_config)
{
        struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
        u32 pclk;
        DRM_DEBUG_KMS("\n");

        pipe_config->output_types |= BIT(INTEL_OUTPUT_DSI);

        if (IS_GEN9_LP(dev_priv)) {
                bxt_dsi_get_pipe_config(encoder, pipe_config);
                pclk = bxt_dsi_get_pclk(encoder, pipe_config);
        } else {
                pclk = vlv_dsi_get_pclk(encoder, pipe_config);
        }

        if (pclk) {
                pipe_config->base.adjusted_mode.crtc_clock = pclk;
                pipe_config->port_clock = pclk;
        }
}

/* return txclkesc cycles in terms of divider and duration in us */
static u16 txclkesc(u32 divider, unsigned int us)
{
        switch (divider) {
        case ESCAPE_CLOCK_DIVIDER_1:
        default:
                return 20 * us;
        case ESCAPE_CLOCK_DIVIDER_2:
                return 10 * us;
        case ESCAPE_CLOCK_DIVIDER_4:
                return 5 * us;
        }
}

static void set_dsi_timings(struct drm_encoder *encoder,
                            const struct drm_display_mode *adjusted_mode)
{
        struct drm_device *dev = encoder->dev;
        struct drm_i915_private *dev_priv = to_i915(dev);
        struct intel_dsi *intel_dsi = enc_to_intel_dsi(encoder);
        enum port port;
        unsigned int bpp = mipi_dsi_pixel_format_to_bpp(intel_dsi->pixel_format);
        unsigned int lane_count = intel_dsi->lane_count;

        u16 hactive, hfp, hsync, hbp, vfp, vsync, vbp;

        hactive = adjusted_mode->crtc_hdisplay;
        hfp = adjusted_mode->crtc_hsync_start - adjusted_mode->crtc_hdisplay;
        hsync = adjusted_mode->crtc_hsync_end - adjusted_mode->crtc_hsync_start;
        hbp = adjusted_mode->crtc_htotal - adjusted_mode->crtc_hsync_end;

        if (intel_dsi->dual_link) {
                hactive /= 2;
                if (intel_dsi->dual_link == DSI_DUAL_LINK_FRONT_BACK)
                        hactive += intel_dsi->pixel_overlap;
                hfp /= 2;
                hsync /= 2;
                hbp /= 2;
        }

        vfp = adjusted_mode->crtc_vsync_start - adjusted_mode->crtc_vdisplay;
        vsync = adjusted_mode->crtc_vsync_end - adjusted_mode->crtc_vsync_start;
        vbp = adjusted_mode->crtc_vtotal - adjusted_mode->crtc_vsync_end;

        /* horizontal values are in terms of high speed byte clock */
        hactive = txbyteclkhs(hactive, bpp, lane_count,
                              intel_dsi->burst_mode_ratio);
        hfp = txbyteclkhs(hfp, bpp, lane_count, intel_dsi->burst_mode_ratio);
        hsync = txbyteclkhs(hsync, bpp, lane_count,
                            intel_dsi->burst_mode_ratio);
        hbp = txbyteclkhs(hbp, bpp, lane_count, intel_dsi->burst_mode_ratio);

        for_each_dsi_port(port, intel_dsi->ports) {
                if (IS_GEN9_LP(dev_priv)) {
                        /*
                         * Program hdisplay and vdisplay on MIPI transcoder.
                         * This is different from calculated hactive and
                         * vactive, as they are calculated per channel basis,
                         * whereas these values should be based on resolution.
                         */
                        I915_WRITE(BXT_MIPI_TRANS_HACTIVE(port),
                                   adjusted_mode->crtc_hdisplay);
                        I915_WRITE(BXT_MIPI_TRANS_VACTIVE(port),
                                   adjusted_mode->crtc_vdisplay);
                        I915_WRITE(BXT_MIPI_TRANS_VTOTAL(port),
                                   adjusted_mode->crtc_vtotal);
                }

                I915_WRITE(MIPI_HACTIVE_AREA_COUNT(port), hactive);
                I915_WRITE(MIPI_HFP_COUNT(port), hfp);

                /* meaningful for video mode non-burst sync pulse mode only,
                 * can be zero for non-burst sync events and burst modes */
                I915_WRITE(MIPI_HSYNC_PADDING_COUNT(port), hsync);
                I915_WRITE(MIPI_HBP_COUNT(port), hbp);

                /* vertical values are in terms of lines */
                I915_WRITE(MIPI_VFP_COUNT(port), vfp);
                I915_WRITE(MIPI_VSYNC_PADDING_COUNT(port), vsync);
                I915_WRITE(MIPI_VBP_COUNT(port), vbp);
        }
}

static u32 pixel_format_to_reg(enum mipi_dsi_pixel_format fmt)
{
        switch (fmt) {
        case MIPI_DSI_FMT_RGB888:
                return VID_MODE_FORMAT_RGB888;
        case MIPI_DSI_FMT_RGB666:
                return VID_MODE_FORMAT_RGB666;
        case MIPI_DSI_FMT_RGB666_PACKED:
                return VID_MODE_FORMAT_RGB666_PACKED;
        case MIPI_DSI_FMT_RGB565:
                return VID_MODE_FORMAT_RGB565;
        default:
                MISSING_CASE(fmt);
                return VID_MODE_FORMAT_RGB666;
        }
}

static void intel_dsi_prepare(struct intel_encoder *intel_encoder,
                              const struct intel_crtc_state *pipe_config)
{
        struct drm_encoder *encoder = &intel_encoder->base;
        struct drm_device *dev = encoder->dev;
        struct drm_i915_private *dev_priv = to_i915(dev);
        struct intel_crtc *intel_crtc = to_intel_crtc(pipe_config->base.crtc);
        struct intel_dsi *intel_dsi = enc_to_intel_dsi(encoder);
        const struct drm_display_mode *adjusted_mode = &pipe_config->base.adjusted_mode;
        enum port port;
        unsigned int bpp = mipi_dsi_pixel_format_to_bpp(intel_dsi->pixel_format);
        u32 val, tmp;
        u16 mode_hdisplay;

        DRM_DEBUG_KMS("pipe %c\n", pipe_name(intel_crtc->pipe));

        mode_hdisplay = adjusted_mode->crtc_hdisplay;

        if (intel_dsi->dual_link) {
                mode_hdisplay /= 2;
                if (intel_dsi->dual_link == DSI_DUAL_LINK_FRONT_BACK)
                        mode_hdisplay += intel_dsi->pixel_overlap;
        }

        for_each_dsi_port(port, intel_dsi->ports) {
                if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv)) {
                        /*
                         * escape clock divider, 20MHz, shared for A and C.
                         * device ready must be off when doing this! txclkesc?
                         */
                        tmp = I915_READ(MIPI_CTRL(PORT_A));
                        tmp &= ~ESCAPE_CLOCK_DIVIDER_MASK;
                        I915_WRITE(MIPI_CTRL(PORT_A), tmp |
                                        ESCAPE_CLOCK_DIVIDER_1);

                        /* read request priority is per pipe */
                        tmp = I915_READ(MIPI_CTRL(port));
                        tmp &= ~READ_REQUEST_PRIORITY_MASK;
                        I915_WRITE(MIPI_CTRL(port), tmp |
                                        READ_REQUEST_PRIORITY_HIGH);
                } else if (IS_GEN9_LP(dev_priv)) {
                        enum pipe pipe = intel_crtc->pipe;

                        tmp = I915_READ(MIPI_CTRL(port));
                        tmp &= ~BXT_PIPE_SELECT_MASK;

                        tmp |= BXT_PIPE_SELECT(pipe);
                        I915_WRITE(MIPI_CTRL(port), tmp);
                }

                /* XXX: why here, why like this? handling in irq handler?! */
                I915_WRITE(MIPI_INTR_STAT(port), 0xffffffff);
                I915_WRITE(MIPI_INTR_EN(port), 0xffffffff);

                I915_WRITE(MIPI_DPHY_PARAM(port), intel_dsi->dphy_reg);

                I915_WRITE(MIPI_DPI_RESOLUTION(port),
                        adjusted_mode->crtc_vdisplay << VERTICAL_ADDRESS_SHIFT |
                        mode_hdisplay << HORIZONTAL_ADDRESS_SHIFT);
        }

        set_dsi_timings(encoder, adjusted_mode);

        val = intel_dsi->lane_count << DATA_LANES_PRG_REG_SHIFT;
        if (is_cmd_mode(intel_dsi)) {
                val |= intel_dsi->channel << CMD_MODE_CHANNEL_NUMBER_SHIFT;
                val |= CMD_MODE_DATA_WIDTH_8_BIT; /* XXX */
        } else {
                val |= intel_dsi->channel << VID_MODE_CHANNEL_NUMBER_SHIFT;
                val |= pixel_format_to_reg(intel_dsi->pixel_format);
        }

        tmp = 0;
        if (intel_dsi->eotp_pkt == 0)
                tmp |= EOT_DISABLE;
        if (intel_dsi->clock_stop)
                tmp |= CLOCKSTOP;

        if (IS_GEN9_LP(dev_priv)) {
                tmp |= BXT_DPHY_DEFEATURE_EN;
                if (!is_cmd_mode(intel_dsi))
                        tmp |= BXT_DEFEATURE_DPI_FIFO_CTR;
        }

        for_each_dsi_port(port, intel_dsi->ports) {
                I915_WRITE(MIPI_DSI_FUNC_PRG(port), val);

                /* timeouts for recovery. one frame IIUC. if counter expires,
                 * EOT and stop state. */

                /*
                 * In burst mode, value greater than one DPI line Time in byte
                 * clock (txbyteclkhs) To timeout this timer 1+ of the above
                 * said value is recommended.
                 *
                 * In non-burst mode, Value greater than one DPI frame time in
                 * byte clock(txbyteclkhs) To timeout this timer 1+ of the above
                 * said value is recommended.
                 *
                 * In DBI only mode, value greater than one DBI frame time in
                 * byte clock(txbyteclkhs) To timeout this timer 1+ of the above
                 * said value is recommended.
                 */

                if (is_vid_mode(intel_dsi) &&
                        intel_dsi->video_mode_format == VIDEO_MODE_BURST) {
                        I915_WRITE(MIPI_HS_TX_TIMEOUT(port),
                                txbyteclkhs(adjusted_mode->crtc_htotal, bpp,
                                            intel_dsi->lane_count,
                                            intel_dsi->burst_mode_ratio) + 1);
                } else {
                        I915_WRITE(MIPI_HS_TX_TIMEOUT(port),
                                txbyteclkhs(adjusted_mode->crtc_vtotal *
                                            adjusted_mode->crtc_htotal,
                                            bpp, intel_dsi->lane_count,
                                            intel_dsi->burst_mode_ratio) + 1);
                }
                I915_WRITE(MIPI_LP_RX_TIMEOUT(port), intel_dsi->lp_rx_timeout);
                I915_WRITE(MIPI_TURN_AROUND_TIMEOUT(port),
                                                intel_dsi->turn_arnd_val);
                I915_WRITE(MIPI_DEVICE_RESET_TIMER(port),
                                                intel_dsi->rst_timer_val);

                /* dphy stuff */

                /* in terms of low power clock */
                I915_WRITE(MIPI_INIT_COUNT(port),
                                txclkesc(intel_dsi->escape_clk_div, 100));

                if (IS_GEN9_LP(dev_priv) && (!intel_dsi->dual_link)) {
                        /*
                         * BXT spec says write MIPI_INIT_COUNT for
                         * both the ports, even if only one is
                         * getting used. So write the other port
                         * if not in dual link mode.
                         */
                        I915_WRITE(MIPI_INIT_COUNT(port ==
                                                PORT_A ? PORT_C : PORT_A),
                                        intel_dsi->init_count);
                }

                /* recovery disables */
                I915_WRITE(MIPI_EOT_DISABLE(port), tmp);

                /* in terms of low power clock */
                I915_WRITE(MIPI_INIT_COUNT(port), intel_dsi->init_count);

                /* in terms of txbyteclkhs. actual high to low switch +
                 * MIPI_STOP_STATE_STALL * MIPI_LP_BYTECLK.
                 *
                 * XXX: write MIPI_STOP_STATE_STALL?
                 */
                I915_WRITE(MIPI_HIGH_LOW_SWITCH_COUNT(port),
                                                intel_dsi->hs_to_lp_count);

                /* XXX: low power clock equivalence in terms of byte clock.
                 * the number of byte clocks occupied in one low power clock.
                 * based on txbyteclkhs and txclkesc.
                 * txclkesc time / txbyteclk time * (105 + MIPI_STOP_STATE_STALL
                 * ) / 105.???
                 */
                I915_WRITE(MIPI_LP_BYTECLK(port), intel_dsi->lp_byte_clk);

                if (IS_GEMINILAKE(dev_priv)) {
                        I915_WRITE(MIPI_TLPX_TIME_COUNT(port),
                                        intel_dsi->lp_byte_clk);
                        /* Shadow of DPHY reg */
                        I915_WRITE(MIPI_CLK_LANE_TIMING(port),
                                        intel_dsi->dphy_reg);
                }

                /* the bw essential for transmitting 16 long packets containing
                 * 252 bytes meant for dcs write memory command is programmed in
                 * this register in terms of byte clocks. based on dsi transfer
                 * rate and the number of lanes configured the time taken to
                 * transmit 16 long packets in a dsi stream varies. */
                I915_WRITE(MIPI_DBI_BW_CTRL(port), intel_dsi->bw_timer);

                I915_WRITE(MIPI_CLK_LANE_SWITCH_TIME_CNT(port),
                intel_dsi->clk_lp_to_hs_count << LP_HS_SSW_CNT_SHIFT |
                intel_dsi->clk_hs_to_lp_count << HS_LP_PWR_SW_CNT_SHIFT);

                if (is_vid_mode(intel_dsi))
                        /* Some panels might have resolution which is not a
                         * multiple of 64 like 1366 x 768. Enable RANDOM
                         * resolution support for such panels by default */
                        I915_WRITE(MIPI_VIDEO_MODE_FORMAT(port),
                                intel_dsi->video_frmt_cfg_bits |
                                intel_dsi->video_mode_format |
                                IP_TG_CONFIG |
                                RANDOM_DPI_DISPLAY_RESOLUTION);
        }
}

static void intel_dsi_unprepare(struct intel_encoder *encoder)
{
        struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
        struct intel_dsi *intel_dsi = enc_to_intel_dsi(&encoder->base);
        enum port port;
        u32 val;

        if (IS_GEMINILAKE(dev_priv))
                return;

        for_each_dsi_port(port, intel_dsi->ports) {
                /* Panel commands can be sent when clock is in LP11 */
                I915_WRITE(MIPI_DEVICE_READY(port), 0x0);

                if (IS_GEN9_LP(dev_priv))
                        bxt_dsi_reset_clocks(encoder, port);
                else
                        vlv_dsi_reset_clocks(encoder, port);
                I915_WRITE(MIPI_EOT_DISABLE(port), CLOCKSTOP);

                val = I915_READ(MIPI_DSI_FUNC_PRG(port));
                val &= ~VID_MODE_FORMAT_MASK;
                I915_WRITE(MIPI_DSI_FUNC_PRG(port), val);

                I915_WRITE(MIPI_DEVICE_READY(port), 0x1);
        }
}

static void intel_dsi_encoder_destroy(struct drm_encoder *encoder)
{
        struct intel_dsi *intel_dsi = enc_to_intel_dsi(encoder);

        /* dispose of the gpios */
        if (intel_dsi->gpio_panel)
                gpiod_put(intel_dsi->gpio_panel);

        intel_encoder_destroy(encoder);
}

static const struct drm_encoder_funcs intel_dsi_funcs = {
        .destroy = intel_dsi_encoder_destroy,
};

static const struct drm_connector_helper_funcs intel_dsi_connector_helper_funcs = {
        .get_modes = intel_dsi_get_modes,
        .mode_valid = intel_dsi_mode_valid,
        .atomic_check = intel_digital_connector_atomic_check,
};

static const struct drm_connector_funcs intel_dsi_connector_funcs = {
        .late_register = intel_connector_register,
        .early_unregister = intel_connector_unregister,
        .destroy = intel_connector_destroy,
        .fill_modes = drm_helper_probe_single_connector_modes,
        .atomic_get_property = intel_digital_connector_atomic_get_property,
        .atomic_set_property = intel_digital_connector_atomic_set_property,
        .atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
        .atomic_duplicate_state = intel_digital_connector_duplicate_state,
};

static enum drm_panel_orientation
vlv_dsi_get_hw_panel_orientation(struct intel_connector *connector)
{
        struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
        struct intel_encoder *encoder = connector->encoder;
        enum intel_display_power_domain power_domain;
        enum drm_panel_orientation orientation;
        struct intel_plane *plane;
        struct intel_crtc *crtc;
        intel_wakeref_t wakeref;
        enum pipe pipe;
        u32 val;

        if (!encoder->get_hw_state(encoder, &pipe))
                return DRM_MODE_PANEL_ORIENTATION_UNKNOWN;

        crtc = intel_get_crtc_for_pipe(dev_priv, pipe);
        plane = to_intel_plane(crtc->base.primary);

        power_domain = POWER_DOMAIN_PIPE(pipe);
        wakeref = intel_display_power_get_if_enabled(dev_priv, power_domain);
        if (!wakeref)
                return DRM_MODE_PANEL_ORIENTATION_UNKNOWN;

        val = I915_READ(DSPCNTR(plane->i9xx_plane));

        if (!(val & DISPLAY_PLANE_ENABLE))
                orientation = DRM_MODE_PANEL_ORIENTATION_UNKNOWN;
        else if (val & DISPPLANE_ROTATE_180)
                orientation = DRM_MODE_PANEL_ORIENTATION_BOTTOM_UP;
        else
                orientation = DRM_MODE_PANEL_ORIENTATION_NORMAL;

        intel_display_power_put(dev_priv, power_domain, wakeref);

        return orientation;
}

static enum drm_panel_orientation
vlv_dsi_get_panel_orientation(struct intel_connector *connector)
{
        struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
        enum drm_panel_orientation orientation;

        if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv)) {
                orientation = vlv_dsi_get_hw_panel_orientation(connector);
                if (orientation != DRM_MODE_PANEL_ORIENTATION_UNKNOWN)
                        return orientation;
        }

        return intel_dsi_get_panel_orientation(connector);
}

static void intel_dsi_add_properties(struct intel_connector *connector)
{
        struct drm_i915_private *dev_priv = to_i915(connector->base.dev);

        if (connector->panel.fixed_mode) {
                u32 allowed_scalers;

                allowed_scalers = BIT(DRM_MODE_SCALE_ASPECT) | BIT(DRM_MODE_SCALE_FULLSCREEN);
                if (!HAS_GMCH(dev_priv))
                        allowed_scalers |= BIT(DRM_MODE_SCALE_CENTER);

                drm_connector_attach_scaling_mode_property(&connector->base,
                                                                allowed_scalers);

                connector->base.state->scaling_mode = DRM_MODE_SCALE_ASPECT;

                connector->base.display_info.panel_orientation =
                        vlv_dsi_get_panel_orientation(connector);
                drm_connector_init_panel_orientation_property(
                                &connector->base,
                                connector->panel.fixed_mode->hdisplay,
                                connector->panel.fixed_mode->vdisplay);
        }
}

#define NS_KHZ_RATIO            1000000

#define PREPARE_CNT_MAX         0x3F
#define EXIT_ZERO_CNT_MAX       0x3F
#define CLK_ZERO_CNT_MAX        0xFF
#define TRAIL_CNT_MAX           0x1F

static void vlv_dphy_param_init(struct intel_dsi *intel_dsi)
{
        struct drm_device *dev = intel_dsi->base.base.dev;
        struct drm_i915_private *dev_priv = to_i915(dev);
        struct mipi_config *mipi_config = dev_priv->vbt.dsi.config;
        u32 tlpx_ns, extra_byte_count, tlpx_ui;
        u32 ui_num, ui_den;
        u32 prepare_cnt, exit_zero_cnt, clk_zero_cnt, trail_cnt;
        u32 ths_prepare_ns, tclk_trail_ns;
        u32 tclk_prepare_clkzero, ths_prepare_hszero;
        u32 lp_to_hs_switch, hs_to_lp_switch;
        u32 mul;

        tlpx_ns = intel_dsi_tlpx_ns(intel_dsi);

        switch (intel_dsi->lane_count) {
        case 1:
        case 2:
                extra_byte_count = 2;
                break;
        case 3:
                extra_byte_count = 4;
                break;
        case 4:
        default:
                extra_byte_count = 3;
                break;
        }

        /* in Kbps */
        ui_num = NS_KHZ_RATIO;
        ui_den = intel_dsi_bitrate(intel_dsi);

        tclk_prepare_clkzero = mipi_config->tclk_prepare_clkzero;
        ths_prepare_hszero = mipi_config->ths_prepare_hszero;

        /*
         * B060
         * LP byte clock = TLPX/ (8UI)
         */
        intel_dsi->lp_byte_clk = DIV_ROUND_UP(tlpx_ns * ui_den, 8 * ui_num);

        /* DDR clock period = 2 * UI
         * UI(sec) = 1/(bitrate * 10^3) (bitrate is in KHZ)
         * UI(nsec) = 10^6 / bitrate
         * DDR clock period (nsec) = 2 * UI = (2 * 10^6)/ bitrate
         * DDR clock count  = ns_value / DDR clock period
         *
         * For GEMINILAKE dphy_param_reg will be programmed in terms of
         * HS byte clock count for other platform in HS ddr clock count
         */
        mul = IS_GEMINILAKE(dev_priv) ? 8 : 2;
        ths_prepare_ns = max(mipi_config->ths_prepare,
                             mipi_config->tclk_prepare);

        /* prepare count */
        prepare_cnt = DIV_ROUND_UP(ths_prepare_ns * ui_den, ui_num * mul);

        if (prepare_cnt > PREPARE_CNT_MAX) {
                DRM_DEBUG_KMS("prepare count too high %u\n", prepare_cnt);
                prepare_cnt = PREPARE_CNT_MAX;
        }

        /* exit zero count */
        exit_zero_cnt = DIV_ROUND_UP(
                                (ths_prepare_hszero - ths_prepare_ns) * ui_den,
                                ui_num * mul
                                );

        /*
         * Exit zero is unified val ths_zero and ths_exit
         * minimum value for ths_exit = 110ns
         * min (exit_zero_cnt * 2) = 110/UI
         * exit_zero_cnt = 55/UI
         */
        if (exit_zero_cnt < (55 * ui_den / ui_num) && (55 * ui_den) % ui_num)
                exit_zero_cnt += 1;

        if (exit_zero_cnt > EXIT_ZERO_CNT_MAX) {
                DRM_DEBUG_KMS("exit zero count too high %u\n", exit_zero_cnt);
                exit_zero_cnt = EXIT_ZERO_CNT_MAX;
        }

        /* clk zero count */
        clk_zero_cnt = DIV_ROUND_UP(
                                (tclk_prepare_clkzero - ths_prepare_ns)
                                * ui_den, ui_num * mul);

        if (clk_zero_cnt > CLK_ZERO_CNT_MAX) {
                DRM_DEBUG_KMS("clock zero count too high %u\n", clk_zero_cnt);
                clk_zero_cnt = CLK_ZERO_CNT_MAX;
        }

        /* trail count */
        tclk_trail_ns = max(mipi_config->tclk_trail, mipi_config->ths_trail);
        trail_cnt = DIV_ROUND_UP(tclk_trail_ns * ui_den, ui_num * mul);

        if (trail_cnt > TRAIL_CNT_MAX) {
                DRM_DEBUG_KMS("trail count too high %u\n", trail_cnt);
                trail_cnt = TRAIL_CNT_MAX;
        }

        /* B080 */
        intel_dsi->dphy_reg = exit_zero_cnt << 24 | trail_cnt << 16 |
                                                clk_zero_cnt << 8 | prepare_cnt;

        /*
         * LP to HS switch count = 4TLPX + PREP_COUNT * mul + EXIT_ZERO_COUNT *
         *                                      mul + 10UI + Extra Byte Count
         *
         * HS to LP switch count = THS-TRAIL + 2TLPX + Extra Byte Count
         * Extra Byte Count is calculated according to number of lanes.
         * High Low Switch Count is the Max of LP to HS and
         * HS to LP switch count
         *
         */
        tlpx_ui = DIV_ROUND_UP(tlpx_ns * ui_den, ui_num);

        /* B044 */
        /* FIXME:
         * The comment above does not match with the code */
        lp_to_hs_switch = DIV_ROUND_UP(4 * tlpx_ui + prepare_cnt * mul +
                                                exit_zero_cnt * mul + 10, 8);

        hs_to_lp_switch = DIV_ROUND_UP(mipi_config->ths_trail + 2 * tlpx_ui, 8);

        intel_dsi->hs_to_lp_count = max(lp_to_hs_switch, hs_to_lp_switch);
        intel_dsi->hs_to_lp_count += extra_byte_count;

        /* B088 */
        /* LP -> HS for clock lanes
         * LP clk sync + LP11 + LP01 + tclk_prepare + tclk_zero +
         *                                              extra byte count
         * 2TPLX + 1TLPX + 1 TPLX(in ns) + prepare_cnt * 2 + clk_zero_cnt *
         *                                      2(in UI) + extra byte count
         * In byteclks = (4TLPX + prepare_cnt * 2 + clk_zero_cnt *2 (in UI)) /
         *                                      8 + extra byte count
         */
        intel_dsi->clk_lp_to_hs_count =
                DIV_ROUND_UP(
                        4 * tlpx_ui + prepare_cnt * 2 +
                        clk_zero_cnt * 2,
                        8);

        intel_dsi->clk_lp_to_hs_count += extra_byte_count;

        /* HS->LP for Clock Lanes
         * Low Power clock synchronisations + 1Tx byteclk + tclk_trail +
         *                                              Extra byte count
         * 2TLPX + 8UI + (trail_count*2)(in UI) + Extra byte count
         * In byteclks = (2*TLpx(in UI) + trail_count*2 +8)(in UI)/8 +
         *                                              Extra byte count
         */
        intel_dsi->clk_hs_to_lp_count =
                DIV_ROUND_UP(2 * tlpx_ui + trail_cnt * 2 + 8,
                        8);
        intel_dsi->clk_hs_to_lp_count += extra_byte_count;

        intel_dsi_log_params(intel_dsi);
}

void vlv_dsi_init(struct drm_i915_private *dev_priv)
{
        struct drm_device *dev = &dev_priv->drm;
        struct intel_dsi *intel_dsi;
        struct intel_encoder *intel_encoder;
        struct drm_encoder *encoder;
        struct intel_connector *intel_connector;
        struct drm_connector *connector;
        struct drm_display_mode *current_mode, *fixed_mode;
        enum port port;

        DRM_DEBUG_KMS("\n");

        /* There is no detection method for MIPI so rely on VBT */
        if (!intel_bios_is_dsi_present(dev_priv, &port))
                return;

        if (IS_GEN9_LP(dev_priv))
                dev_priv->mipi_mmio_base = BXT_MIPI_BASE;
        else
                dev_priv->mipi_mmio_base = VLV_MIPI_BASE;

        intel_dsi = kzalloc(sizeof(*intel_dsi), GFP_KERNEL);
        if (!intel_dsi)
                return;

        intel_connector = intel_connector_alloc();
        if (!intel_connector) {
                kfree(intel_dsi);
                return;
        }

        intel_encoder = &intel_dsi->base;
        encoder = &intel_encoder->base;
        intel_dsi->attached_connector = intel_connector;

        connector = &intel_connector->base;

        drm_encoder_init(dev, encoder, &intel_dsi_funcs, DRM_MODE_ENCODER_DSI,
                         "DSI %c", port_name(port));

        intel_encoder->compute_config = intel_dsi_compute_config;
        intel_encoder->pre_enable = intel_dsi_pre_enable;
        intel_encoder->disable = intel_dsi_disable;
        intel_encoder->post_disable = intel_dsi_post_disable;
        intel_encoder->get_hw_state = intel_dsi_get_hw_state;
        intel_encoder->get_config = intel_dsi_get_config;
        intel_encoder->update_pipe = intel_panel_update_backlight;

        intel_connector->get_hw_state = intel_connector_get_hw_state;

        intel_encoder->port = port;
        intel_encoder->type = INTEL_OUTPUT_DSI;
        intel_encoder->power_domain = POWER_DOMAIN_PORT_DSI;
        intel_encoder->cloneable = 0;

        /*
         * On BYT/CHV, pipe A maps to MIPI DSI port A, pipe B maps to MIPI DSI
         * port C. BXT isn't limited like this.
         */
        if (IS_GEN9_LP(dev_priv))
                intel_encoder->crtc_mask = BIT(PIPE_A) | BIT(PIPE_B) | BIT(PIPE_C);
        else if (port == PORT_A)
                intel_encoder->crtc_mask = BIT(PIPE_A);
        else
                intel_encoder->crtc_mask = BIT(PIPE_B);

        if (dev_priv->vbt.dsi.config->dual_link)
                intel_dsi->ports = BIT(PORT_A) | BIT(PORT_C);
        else
                intel_dsi->ports = BIT(port);

        intel_dsi->dcs_backlight_ports = dev_priv->vbt.dsi.bl_ports;
        intel_dsi->dcs_cabc_ports = dev_priv->vbt.dsi.cabc_ports;

        /* Create a DSI host (and a device) for each port. */
        for_each_dsi_port(port, intel_dsi->ports) {
                struct intel_dsi_host *host;

                host = intel_dsi_host_init(intel_dsi, &intel_dsi_host_ops,
                                           port);
                if (!host)
                        goto err;

                intel_dsi->dsi_hosts[port] = host;
        }

        if (!intel_dsi_vbt_init(intel_dsi, MIPI_DSI_GENERIC_PANEL_ID)) {
                DRM_DEBUG_KMS("no device found\n");
                goto err;
        }

        /* Use clock read-back from current hw-state for fastboot */
        current_mode = intel_encoder_current_mode(intel_encoder);
        if (current_mode) {
                DRM_DEBUG_KMS("Calculated pclk %d GOP %d\n",
                              intel_dsi->pclk, current_mode->clock);
                if (intel_fuzzy_clock_check(intel_dsi->pclk,
                                            current_mode->clock)) {
                        DRM_DEBUG_KMS("Using GOP pclk\n");
                        intel_dsi->pclk = current_mode->clock;
                }

                kfree(current_mode);
        }

        vlv_dphy_param_init(intel_dsi);

        /*
         * In case of BYT with CRC PMIC, we need to use GPIO for
         * Panel control.
         */
        if ((IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv)) &&
            (dev_priv->vbt.dsi.config->pwm_blc == PPS_BLC_PMIC)) {
                intel_dsi->gpio_panel =
                        gpiod_get(dev->dev, "panel", GPIOD_OUT_HIGH);

                if (IS_ERR(intel_dsi->gpio_panel)) {
                        DRM_ERROR("Failed to own gpio for panel control\n");
                        intel_dsi->gpio_panel = NULL;
                }
        }

        drm_connector_init(dev, connector, &intel_dsi_connector_funcs,
                           DRM_MODE_CONNECTOR_DSI);

        drm_connector_helper_add(connector, &intel_dsi_connector_helper_funcs);

        connector->display_info.subpixel_order = SubPixelHorizontalRGB; /*XXX*/
        connector->interlace_allowed = false;
        connector->doublescan_allowed = false;

        intel_connector_attach_encoder(intel_connector, intel_encoder);

        mutex_lock(&dev->mode_config.mutex);
        fixed_mode = intel_panel_vbt_fixed_mode(intel_connector);
        mutex_unlock(&dev->mode_config.mutex);

        if (!fixed_mode) {
                DRM_DEBUG_KMS("no fixed mode\n");
                goto err_cleanup_connector;
        }

        intel_panel_init(&intel_connector->panel, fixed_mode, NULL);
        intel_panel_setup_backlight(connector, INVALID_PIPE);

        intel_dsi_add_properties(intel_connector);

        return;

err_cleanup_connector:
        drm_connector_cleanup(&intel_connector->base);
err:
        drm_encoder_cleanup(&intel_encoder->base);
        kfree(intel_dsi);
        kfree(intel_connector);
}