/*
 * Copyright (C) 2013-2017 Oracle Corporation
 * This file is based on ast_mode.c
 * Copyright 2012 Red Hat Inc.
 * Parts based on xf86-video-ast
 * Copyright (c) 2005 ASPEED Technology 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, sub license, 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 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 NON-INFRINGEMENT. IN NO EVENT SHALL
 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS 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.
 *
 * The above copyright notice and this permission notice (including the
 * next paragraph) shall be included in all copies or substantial portions
 * of the Software.
 *
 */
/*
 * Authors: Dave Airlie <airlied@redhat.com>
 *          Michael Thayer <michael.thayer@oracle.com,
 *          Hans de Goede <hdegoede@redhat.com>
 */
#include <linux/export.h>
#include <drm/drm_crtc_helper.h>
#include <drm/drm_plane_helper.h>

#include "vbox_drv.h"
#include "vboxvideo.h"
#include "hgsmi_channels.h"

static int vbox_cursor_set2(struct drm_crtc *crtc, struct drm_file *file_priv,
                            u32 handle, u32 width, u32 height,
                            s32 hot_x, s32 hot_y);
static int vbox_cursor_move(struct drm_crtc *crtc, int x, int y);

/**
 * Set a graphics mode.  Poke any required values into registers, do an HGSMI
 * mode set and tell the host we support advanced graphics functions.
 */
static void vbox_do_modeset(struct drm_crtc *crtc,
                            const struct drm_display_mode *mode)
{
        struct vbox_crtc *vbox_crtc = to_vbox_crtc(crtc);
        struct vbox_private *vbox;
        int width, height, bpp, pitch;
        u16 flags;
        s32 x_offset, y_offset;

        vbox = crtc->dev->dev_private;
        width = mode->hdisplay ? mode->hdisplay : 640;
        height = mode->vdisplay ? mode->vdisplay : 480;
        bpp = crtc->enabled ? CRTC_FB(crtc)->format->cpp[0] * 8 : 32;
        pitch = crtc->enabled ? CRTC_FB(crtc)->pitches[0] : width * bpp / 8;
        x_offset = vbox->single_framebuffer ? crtc->x : vbox_crtc->x_hint;
        y_offset = vbox->single_framebuffer ? crtc->y : vbox_crtc->y_hint;

        /*
         * This is the old way of setting graphics modes.  It assumed one screen
         * and a frame-buffer at the start of video RAM.  On older versions of
         * VirtualBox, certain parts of the code still assume that the first
         * screen is programmed this way, so try to fake it.
         */
        if (vbox_crtc->crtc_id == 0 && crtc->enabled &&
            vbox_crtc->fb_offset / pitch < 0xffff - crtc->y &&
            vbox_crtc->fb_offset % (bpp / 8) == 0) {
                vbox_write_ioport(VBE_DISPI_INDEX_XRES, width);
                vbox_write_ioport(VBE_DISPI_INDEX_YRES, height);
                vbox_write_ioport(VBE_DISPI_INDEX_VIRT_WIDTH, pitch * 8 / bpp);
                vbox_write_ioport(VBE_DISPI_INDEX_BPP,
                                  CRTC_FB(crtc)->format->cpp[0] * 8);
                vbox_write_ioport(VBE_DISPI_INDEX_ENABLE, VBE_DISPI_ENABLED);
                vbox_write_ioport(
                        VBE_DISPI_INDEX_X_OFFSET,
                        vbox_crtc->fb_offset % pitch / bpp * 8 + crtc->x);
                vbox_write_ioport(VBE_DISPI_INDEX_Y_OFFSET,
                                  vbox_crtc->fb_offset / pitch + crtc->y);
        }

        flags = VBVA_SCREEN_F_ACTIVE;
        flags |= (crtc->enabled && !vbox_crtc->blanked) ?
                 0 : VBVA_SCREEN_F_BLANK;
        flags |= vbox_crtc->disconnected ? VBVA_SCREEN_F_DISABLED : 0;
        hgsmi_process_display_info(vbox->guest_pool, vbox_crtc->crtc_id,
                                   x_offset, y_offset,
                                   crtc->x * bpp / 8 + crtc->y * pitch,
                                   pitch, width, height,
                                   vbox_crtc->blanked ? 0 : bpp, flags);
}

static int vbox_set_view(struct drm_crtc *crtc)
{
        struct vbox_crtc *vbox_crtc = to_vbox_crtc(crtc);
        struct vbox_private *vbox = crtc->dev->dev_private;
        struct vbva_infoview *p;

        /*
         * Tell the host about the view.  This design originally targeted the
         * Windows XP driver architecture and assumed that each screen would
         * have a dedicated frame buffer with the command buffer following it,
         * the whole being a "view".  The host works out which screen a command
         * buffer belongs to by checking whether it is in the first view, then
         * whether it is in the second and so on.  The first match wins.  We
         * cheat around this by making the first view be the managed memory
         * plus the first command buffer, the second the same plus the second
         * buffer and so on.
         */
        p = hgsmi_buffer_alloc(vbox->guest_pool, sizeof(*p),
                               HGSMI_CH_VBVA, VBVA_INFO_VIEW);
        if (!p)
                return -ENOMEM;

        p->view_index = vbox_crtc->crtc_id;
        p->view_offset = vbox_crtc->fb_offset;
        p->view_size = vbox->available_vram_size - vbox_crtc->fb_offset +
                       vbox_crtc->crtc_id * VBVA_MIN_BUFFER_SIZE;
        p->max_screen_size = vbox->available_vram_size - vbox_crtc->fb_offset;

        hgsmi_buffer_submit(vbox->guest_pool, p);
        hgsmi_buffer_free(vbox->guest_pool, p);

        return 0;
}

static void vbox_crtc_dpms(struct drm_crtc *crtc, int mode)
{
        struct vbox_crtc *vbox_crtc = to_vbox_crtc(crtc);
        struct vbox_private *vbox = crtc->dev->dev_private;

        switch (mode) {
        case DRM_MODE_DPMS_ON:
                vbox_crtc->blanked = false;
                break;
        case DRM_MODE_DPMS_STANDBY:
        case DRM_MODE_DPMS_SUSPEND:
        case DRM_MODE_DPMS_OFF:
                vbox_crtc->blanked = true;
                break;
        }

        mutex_lock(&vbox->hw_mutex);
        vbox_do_modeset(crtc, &crtc->hwmode);
        mutex_unlock(&vbox->hw_mutex);
}

static bool vbox_crtc_mode_fixup(struct drm_crtc *crtc,
                                 const struct drm_display_mode *mode,
                                 struct drm_display_mode *adjusted_mode)
{
        return true;
}

/*
 * Try to map the layout of virtual screens to the range of the input device.
 * Return true if we need to re-set the crtc modes due to screen offset
 * changes.
 */
static bool vbox_set_up_input_mapping(struct vbox_private *vbox)
{
        struct drm_crtc *crtci;
        struct drm_connector *connectori;
        struct drm_framebuffer *fb1 = NULL;
        bool single_framebuffer = true;
        bool old_single_framebuffer = vbox->single_framebuffer;
        u16 width = 0, height = 0;

        /*
         * Are we using an X.Org-style single large frame-buffer for all crtcs?
         * If so then screen layout can be deduced from the crtc offsets.
         * Same fall-back if this is the fbdev frame-buffer.
         */
        list_for_each_entry(crtci, &vbox->dev->mode_config.crtc_list, head) {
                if (!fb1) {
                        fb1 = CRTC_FB(crtci);
                        if (to_vbox_framebuffer(fb1) == &vbox->fbdev->afb)
                                break;
                } else if (CRTC_FB(crtci) && fb1 != CRTC_FB(crtci)) {
                        single_framebuffer = false;
                }
        }
        if (single_framebuffer) {
                list_for_each_entry(crtci, &vbox->dev->mode_config.crtc_list,
                                    head) {
                        if (to_vbox_crtc(crtci)->crtc_id != 0)
                                continue;

                        vbox->single_framebuffer = true;
                        vbox->input_mapping_width = CRTC_FB(crtci)->width;
                        vbox->input_mapping_height = CRTC_FB(crtci)->height;
                        return old_single_framebuffer !=
                               vbox->single_framebuffer;
                }
        }
        /* Otherwise calculate the total span of all screens. */
        list_for_each_entry(connectori, &vbox->dev->mode_config.connector_list,
                            head) {
                struct vbox_connector *vbox_connector =
                    to_vbox_connector(connectori);
                struct vbox_crtc *vbox_crtc = vbox_connector->vbox_crtc;

                width = max_t(u16, width, vbox_crtc->x_hint +
                                          vbox_connector->mode_hint.width);
                height = max_t(u16, height, vbox_crtc->y_hint +
                                            vbox_connector->mode_hint.height);
        }

        vbox->single_framebuffer = false;
        vbox->input_mapping_width = width;
        vbox->input_mapping_height = height;

        return old_single_framebuffer != vbox->single_framebuffer;
}

static int vbox_crtc_do_set_base(struct drm_crtc *crtc,
                                 struct drm_framebuffer *old_fb,
                                 struct drm_framebuffer *new_fb,
                                 int x, int y)
{
        struct vbox_private *vbox = crtc->dev->dev_private;
        struct vbox_crtc *vbox_crtc = to_vbox_crtc(crtc);
        struct drm_gem_object *obj;
        struct vbox_framebuffer *vbox_fb;
        struct vbox_bo *bo;
        int ret;
        u64 gpu_addr;

        /* Unpin the previous fb. */
        if (old_fb) {
                vbox_fb = to_vbox_framebuffer(old_fb);
                obj = vbox_fb->obj;
                bo = gem_to_vbox_bo(obj);
                ret = vbox_bo_reserve(bo, false);
                if (ret)
                        return ret;

                vbox_bo_unpin(bo);
                vbox_bo_unreserve(bo);
        }

        vbox_fb = to_vbox_framebuffer(new_fb);
        obj = vbox_fb->obj;
        bo = gem_to_vbox_bo(obj);

        ret = vbox_bo_reserve(bo, false);
        if (ret)
                return ret;

        ret = vbox_bo_pin(bo, TTM_PL_FLAG_VRAM, &gpu_addr);
        if (ret) {
                vbox_bo_unreserve(bo);
                return ret;
        }

        if (&vbox->fbdev->afb == vbox_fb)
                vbox_fbdev_set_base(vbox, gpu_addr);
        vbox_bo_unreserve(bo);

        /* vbox_set_start_address_crt1(crtc, (u32)gpu_addr); */
        vbox_crtc->fb_offset = gpu_addr;
        if (vbox_set_up_input_mapping(vbox)) {
                struct drm_crtc *crtci;

                list_for_each_entry(crtci, &vbox->dev->mode_config.crtc_list,
                                    head) {
                        vbox_set_view(crtc);
                        vbox_do_modeset(crtci, &crtci->mode);
                }
        }

        return 0;
}

static int vbox_crtc_mode_set_base(struct drm_crtc *crtc, int x, int y,
                                   struct drm_framebuffer *old_fb)
{
        return vbox_crtc_do_set_base(crtc, old_fb, CRTC_FB(crtc), x, y);
}

static int vbox_crtc_mode_set(struct drm_crtc *crtc,
                              struct drm_display_mode *mode,
                              struct drm_display_mode *adjusted_mode,
                              int x, int y, struct drm_framebuffer *old_fb)
{
        struct vbox_private *vbox = crtc->dev->dev_private;
        int ret;

        vbox_crtc_mode_set_base(crtc, x, y, old_fb);

        mutex_lock(&vbox->hw_mutex);
        ret = vbox_set_view(crtc);
        if (!ret)
                vbox_do_modeset(crtc, mode);
        hgsmi_update_input_mapping(vbox->guest_pool, 0, 0,
                                   vbox->input_mapping_width,
                                   vbox->input_mapping_height);
        mutex_unlock(&vbox->hw_mutex);

        return ret;
}

static int vbox_crtc_page_flip(struct drm_crtc *crtc,
                               struct drm_framebuffer *fb,
                               struct drm_pending_vblank_event *event,
                               uint32_t page_flip_flags,
                               struct drm_modeset_acquire_ctx *ctx)
{
        struct vbox_private *vbox = crtc->dev->dev_private;
        struct drm_device *drm = vbox->dev;
        unsigned long flags;
        int rc;

        rc = vbox_crtc_do_set_base(crtc, CRTC_FB(crtc), fb, 0, 0);
        if (rc)
                return rc;

        mutex_lock(&vbox->hw_mutex);
        vbox_set_view(crtc);
        vbox_do_modeset(crtc, &crtc->mode);
        mutex_unlock(&vbox->hw_mutex);

        spin_lock_irqsave(&drm->event_lock, flags);

        if (event)
                drm_crtc_send_vblank_event(crtc, event);

        spin_unlock_irqrestore(&drm->event_lock, flags);

        return 0;
}

static void vbox_crtc_disable(struct drm_crtc *crtc)
{
}

static void vbox_crtc_prepare(struct drm_crtc *crtc)
{
}

static void vbox_crtc_commit(struct drm_crtc *crtc)
{
}

static const struct drm_crtc_helper_funcs vbox_crtc_helper_funcs = {
        .dpms = vbox_crtc_dpms,
        .mode_fixup = vbox_crtc_mode_fixup,
        .mode_set = vbox_crtc_mode_set,
        /* .mode_set_base = vbox_crtc_mode_set_base, */
        .disable = vbox_crtc_disable,
        .prepare = vbox_crtc_prepare,
        .commit = vbox_crtc_commit,
};

static void vbox_crtc_reset(struct drm_crtc *crtc)
{
}

static void vbox_crtc_destroy(struct drm_crtc *crtc)
{
        drm_crtc_cleanup(crtc);
        kfree(crtc);
}

static const struct drm_crtc_funcs vbox_crtc_funcs = {
        .cursor_move = vbox_cursor_move,
        .cursor_set2 = vbox_cursor_set2,
        .reset = vbox_crtc_reset,
        .set_config = drm_crtc_helper_set_config,
        /* .gamma_set = vbox_crtc_gamma_set, */
        .page_flip = vbox_crtc_page_flip,
        .destroy = vbox_crtc_destroy,
};

static struct vbox_crtc *vbox_crtc_init(struct drm_device *dev, unsigned int i)
{
        struct vbox_crtc *vbox_crtc;

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

        vbox_crtc->crtc_id = i;

        drm_crtc_init(dev, &vbox_crtc->base, &vbox_crtc_funcs);
        drm_mode_crtc_set_gamma_size(&vbox_crtc->base, 256);
        drm_crtc_helper_add(&vbox_crtc->base, &vbox_crtc_helper_funcs);

        return vbox_crtc;
}

static void vbox_encoder_destroy(struct drm_encoder *encoder)
{
        drm_encoder_cleanup(encoder);
        kfree(encoder);
}

static struct drm_encoder *vbox_best_single_encoder(struct drm_connector
                                                    *connector)
{
        int enc_id = connector->encoder_ids[0];

        /* pick the encoder ids */
        if (enc_id)
                return drm_encoder_find(connector->dev, NULL, enc_id);

        return NULL;
}

static const struct drm_encoder_funcs vbox_enc_funcs = {
        .destroy = vbox_encoder_destroy,
};

static void vbox_encoder_dpms(struct drm_encoder *encoder, int mode)
{
}

static bool vbox_mode_fixup(struct drm_encoder *encoder,
                            const struct drm_display_mode *mode,
                            struct drm_display_mode *adjusted_mode)
{
        return true;
}

static void vbox_encoder_mode_set(struct drm_encoder *encoder,
                                  struct drm_display_mode *mode,
                                  struct drm_display_mode *adjusted_mode)
{
}

static void vbox_encoder_prepare(struct drm_encoder *encoder)
{
}

static void vbox_encoder_commit(struct drm_encoder *encoder)
{
}

static const struct drm_encoder_helper_funcs vbox_enc_helper_funcs = {
        .dpms = vbox_encoder_dpms,
        .mode_fixup = vbox_mode_fixup,
        .prepare = vbox_encoder_prepare,
        .commit = vbox_encoder_commit,
        .mode_set = vbox_encoder_mode_set,
};

static struct drm_encoder *vbox_encoder_init(struct drm_device *dev,
                                             unsigned int i)
{
        struct vbox_encoder *vbox_encoder;

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

        drm_encoder_init(dev, &vbox_encoder->base, &vbox_enc_funcs,
                         DRM_MODE_ENCODER_DAC, NULL);
        drm_encoder_helper_add(&vbox_encoder->base, &vbox_enc_helper_funcs);

        vbox_encoder->base.possible_crtcs = 1 << i;
        return &vbox_encoder->base;
}

/**
 * Generate EDID data with a mode-unique serial number for the virtual
 *  monitor to try to persuade Unity that different modes correspond to
 *  different monitors and it should not try to force the same resolution on
 *  them.
 */
static void vbox_set_edid(struct drm_connector *connector, int width,
                          int height)
{
        enum { EDID_SIZE = 128 };
        unsigned char edid[EDID_SIZE] = {
                0x00, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0x00, /* header */
                0x58, 0x58,     /* manufacturer (VBX) */
                0x00, 0x00,     /* product code */
                0x00, 0x00, 0x00, 0x00, /* serial number goes here */
                0x01,           /* week of manufacture */
                0x00,           /* year of manufacture */
                0x01, 0x03,     /* EDID version */
                0x80,           /* capabilities - digital */
                0x00,           /* horiz. res in cm, zero for projectors */
                0x00,           /* vert. res in cm */
                0x78,           /* display gamma (120 == 2.2). */
                0xEE,           /* features (standby, suspend, off, RGB, std */
                                /* colour space, preferred timing mode) */
                0xEE, 0x91, 0xA3, 0x54, 0x4C, 0x99, 0x26, 0x0F, 0x50, 0x54,
                /* chromaticity for standard colour space. */
                0x00, 0x00, 0x00,       /* no default timings */
                0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
                    0x01, 0x01,
                0x01, 0x01, 0x01, 0x01, /* no standard timings */
                0x00, 0x00, 0x00, 0x06, 0x00, 0x00, 0x06, 0x00, 0x02, 0x02,
                    0x02, 0x02,
                /* descriptor block 1 goes below */
                0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
                /* descriptor block 2, monitor ranges */
                0x00, 0x00, 0x00, 0xFD, 0x00,
                0x00, 0xC8, 0x00, 0xC8, 0x64, 0x00, 0x0A, 0x20, 0x20, 0x20,
                    0x20, 0x20,
                /* 0-200Hz vertical, 0-200KHz horizontal, 1000MHz pixel clock */
                0x20,
                /* descriptor block 3, monitor name */
                0x00, 0x00, 0x00, 0xFC, 0x00,
                'V', 'B', 'O', 'X', ' ', 'm', 'o', 'n', 'i', 't', 'o', 'r',
                '\n',
                /* descriptor block 4: dummy data */
                0x00, 0x00, 0x00, 0x10, 0x00,
                0x0A, 0x20, 0x20, 0x20, 0x20, 0x20,
                0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
                0x20,
                0x00,           /* number of extensions */
                0x00            /* checksum goes here */
        };
        int clock = (width + 6) * (height + 6) * 60 / 10000;
        unsigned int i, sum = 0;

        edid[12] = width & 0xff;
        edid[13] = width >> 8;
        edid[14] = height & 0xff;
        edid[15] = height >> 8;
        edid[54] = clock & 0xff;
        edid[55] = clock >> 8;
        edid[56] = width & 0xff;
        edid[58] = (width >> 4) & 0xf0;
        edid[59] = height & 0xff;
        edid[61] = (height >> 4) & 0xf0;
        for (i = 0; i < EDID_SIZE - 1; ++i)
                sum += edid[i];
        edid[EDID_SIZE - 1] = (0x100 - (sum & 0xFF)) & 0xFF;
        drm_connector_update_edid_property(connector, (struct edid *)edid);
}

static int vbox_get_modes(struct drm_connector *connector)
{
        struct vbox_connector *vbox_connector = NULL;
        struct drm_display_mode *mode = NULL;
        struct vbox_private *vbox = NULL;
        unsigned int num_modes = 0;
        int preferred_width, preferred_height;

        vbox_connector = to_vbox_connector(connector);
        vbox = connector->dev->dev_private;
        /*
         * Heuristic: we do not want to tell the host that we support dynamic
         * resizing unless we feel confident that the user space client using
         * the video driver can handle hot-plug events.  So the first time modes
         * are queried after a "master" switch we tell the host that we do not,
         * and immediately after we send the client a hot-plug notification as
         * a test to see if they will respond and query again.
         * That is also the reason why capabilities are reported to the host at
         * this place in the code rather than elsewhere.
         * We need to report the flags location before reporting the IRQ
         * capability.
         */
        hgsmi_report_flags_location(vbox->guest_pool, GUEST_HEAP_OFFSET(vbox) +
                                    HOST_FLAGS_OFFSET);
        if (vbox_connector->vbox_crtc->crtc_id == 0)
                vbox_report_caps(vbox);
        if (!vbox->initial_mode_queried) {
                if (vbox_connector->vbox_crtc->crtc_id == 0) {
                        vbox->initial_mode_queried = true;
                        vbox_report_hotplug(vbox);
                }
                return drm_add_modes_noedid(connector, 800, 600);
        }
        num_modes = drm_add_modes_noedid(connector, 2560, 1600);
        preferred_width = vbox_connector->mode_hint.width ?
                          vbox_connector->mode_hint.width : 1024;
        preferred_height = vbox_connector->mode_hint.height ?
                           vbox_connector->mode_hint.height : 768;
        mode = drm_cvt_mode(connector->dev, preferred_width, preferred_height,
                            60, false, false, false);
        if (mode) {
                mode->type |= DRM_MODE_TYPE_PREFERRED;
                drm_mode_probed_add(connector, mode);
                ++num_modes;
        }
        vbox_set_edid(connector, preferred_width, preferred_height);

        if (vbox_connector->vbox_crtc->x_hint != -1)
                drm_object_property_set_value(&connector->base,
                        vbox->dev->mode_config.suggested_x_property,
                        vbox_connector->vbox_crtc->x_hint);
        else
                drm_object_property_set_value(&connector->base,
                        vbox->dev->mode_config.suggested_x_property, 0);

        if (vbox_connector->vbox_crtc->y_hint != -1)
                drm_object_property_set_value(&connector->base,
                        vbox->dev->mode_config.suggested_y_property,
                        vbox_connector->vbox_crtc->y_hint);
        else
                drm_object_property_set_value(&connector->base,
                        vbox->dev->mode_config.suggested_y_property, 0);

        return num_modes;
}

static enum drm_mode_status vbox_mode_valid(struct drm_connector *connector,
                           struct drm_display_mode *mode)
{
        return MODE_OK;
}

static void vbox_connector_destroy(struct drm_connector *connector)
{
        drm_connector_unregister(connector);
        drm_connector_cleanup(connector);
        kfree(connector);
}

static enum drm_connector_status
vbox_connector_detect(struct drm_connector *connector, bool force)
{
        struct vbox_connector *vbox_connector;

        vbox_connector = to_vbox_connector(connector);

        return vbox_connector->mode_hint.disconnected ?
            connector_status_disconnected : connector_status_connected;
}

static int vbox_fill_modes(struct drm_connector *connector, u32 max_x,
                           u32 max_y)
{
        struct vbox_connector *vbox_connector;
        struct drm_device *dev;
        struct drm_display_mode *mode, *iterator;

        vbox_connector = to_vbox_connector(connector);
        dev = vbox_connector->base.dev;
        list_for_each_entry_safe(mode, iterator, &connector->modes, head) {
                list_del(&mode->head);
                drm_mode_destroy(dev, mode);
        }

        return drm_helper_probe_single_connector_modes(connector, max_x, max_y);
}

static const struct drm_connector_helper_funcs vbox_connector_helper_funcs = {
        .mode_valid = vbox_mode_valid,
        .get_modes = vbox_get_modes,
        .best_encoder = vbox_best_single_encoder,
};

static const struct drm_connector_funcs vbox_connector_funcs = {
        .dpms = drm_helper_connector_dpms,
        .detect = vbox_connector_detect,
        .fill_modes = vbox_fill_modes,
        .destroy = vbox_connector_destroy,
};

static int vbox_connector_init(struct drm_device *dev,
                               struct vbox_crtc *vbox_crtc,
                               struct drm_encoder *encoder)
{
        struct vbox_connector *vbox_connector;
        struct drm_connector *connector;

        vbox_connector = kzalloc(sizeof(*vbox_connector), GFP_KERNEL);
        if (!vbox_connector)
                return -ENOMEM;

        connector = &vbox_connector->base;
        vbox_connector->vbox_crtc = vbox_crtc;

        drm_connector_init(dev, connector, &vbox_connector_funcs,
                           DRM_MODE_CONNECTOR_VGA);
        drm_connector_helper_add(connector, &vbox_connector_helper_funcs);

        connector->interlace_allowed = 0;
        connector->doublescan_allowed = 0;

        drm_mode_create_suggested_offset_properties(dev);
        drm_object_attach_property(&connector->base,
                                   dev->mode_config.suggested_x_property, 0);
        drm_object_attach_property(&connector->base,
                                   dev->mode_config.suggested_y_property, 0);
        drm_connector_register(connector);

        drm_connector_attach_encoder(connector, encoder);

        return 0;
}

int vbox_mode_init(struct drm_device *dev)
{
        struct vbox_private *vbox = dev->dev_private;
        struct drm_encoder *encoder;
        struct vbox_crtc *vbox_crtc;
        unsigned int i;
        int ret;

        /* vbox_cursor_init(dev); */
        for (i = 0; i < vbox->num_crtcs; ++i) {
                vbox_crtc = vbox_crtc_init(dev, i);
                if (!vbox_crtc)
                        return -ENOMEM;
                encoder = vbox_encoder_init(dev, i);
                if (!encoder)
                        return -ENOMEM;
                ret = vbox_connector_init(dev, vbox_crtc, encoder);
                if (ret)
                        return ret;
        }

        return 0;
}

void vbox_mode_fini(struct drm_device *dev)
{
        /* vbox_cursor_fini(dev); */
}

/**
 * Copy the ARGB image and generate the mask, which is needed in case the host
 * does not support ARGB cursors.  The mask is a 1BPP bitmap with the bit set
 * if the corresponding alpha value in the ARGB image is greater than 0xF0.
 */
static void copy_cursor_image(u8 *src, u8 *dst, u32 width, u32 height,
                              size_t mask_size)
{
        size_t line_size = (width + 7) / 8;
        u32 i, j;

        memcpy(dst + mask_size, src, width * height * 4);
        for (i = 0; i < height; ++i)
                for (j = 0; j < width; ++j)
                        if (((u32 *)src)[i * width + j] > 0xf0000000)
                                dst[i * line_size + j / 8] |= (0x80 >> (j % 8));
}

static int vbox_cursor_set2(struct drm_crtc *crtc, struct drm_file *file_priv,
                            u32 handle, u32 width, u32 height,
                            s32 hot_x, s32 hot_y)
{
        struct vbox_private *vbox = crtc->dev->dev_private;
        struct vbox_crtc *vbox_crtc = to_vbox_crtc(crtc);
        struct ttm_bo_kmap_obj uobj_map;
        size_t data_size, mask_size;
        struct drm_gem_object *obj;
        u32 flags, caps = 0;
        struct vbox_bo *bo;
        bool src_isiomem;
        u8 *dst = NULL;
        u8 *src;
        int ret;

        /*
         * Re-set this regularly as in 5.0.20 and earlier the information was
         * lost on save and restore.
         */
        hgsmi_update_input_mapping(vbox->guest_pool, 0, 0,
                                   vbox->input_mapping_width,
                                   vbox->input_mapping_height);
        if (!handle) {
                bool cursor_enabled = false;
                struct drm_crtc *crtci;

                /* Hide cursor. */
                vbox_crtc->cursor_enabled = false;
                list_for_each_entry(crtci, &vbox->dev->mode_config.crtc_list,
                                    head) {
                        if (to_vbox_crtc(crtci)->cursor_enabled)
                                cursor_enabled = true;
                }

                if (!cursor_enabled)
                        hgsmi_update_pointer_shape(vbox->guest_pool, 0, 0, 0,
                                                   0, 0, NULL, 0);
                return 0;
        }

        vbox_crtc->cursor_enabled = true;

        if (width > VBOX_MAX_CURSOR_WIDTH || height > VBOX_MAX_CURSOR_HEIGHT ||
            width == 0 || height == 0)
                return -EINVAL;

        ret = hgsmi_query_conf(vbox->guest_pool,
                               VBOX_VBVA_CONF32_CURSOR_CAPABILITIES, &caps);
        if (ret)
                return ret;

        if (!(caps & VBOX_VBVA_CURSOR_CAPABILITY_HARDWARE)) {
                /*
                 * -EINVAL means cursor_set2() not supported, -EAGAIN means
                 * retry at once.
                 */
                return -EBUSY;
        }

        obj = drm_gem_object_lookup(file_priv, handle);
        if (!obj) {
                DRM_ERROR("Cannot find cursor object %x for crtc\n", handle);
                return -ENOENT;
        }

        bo = gem_to_vbox_bo(obj);
        ret = vbox_bo_reserve(bo, false);
        if (ret)
                goto out_unref_obj;

        /*
         * The mask must be calculated based on the alpha
         * channel, one bit per ARGB word, and must be 32-bit
         * padded.
         */
        mask_size = ((width + 7) / 8 * height + 3) & ~3;
        data_size = width * height * 4 + mask_size;
        vbox->cursor_hot_x = min_t(u32, max(hot_x, 0), width);
        vbox->cursor_hot_y = min_t(u32, max(hot_y, 0), height);
        vbox->cursor_width = width;
        vbox->cursor_height = height;
        vbox->cursor_data_size = data_size;
        dst = vbox->cursor_data;

        ret = ttm_bo_kmap(&bo->bo, 0, bo->bo.num_pages, &uobj_map);
        if (ret) {
                vbox->cursor_data_size = 0;
                goto out_unreserve_bo;
        }

        src = ttm_kmap_obj_virtual(&uobj_map, &src_isiomem);
        if (src_isiomem) {
                DRM_ERROR("src cursor bo not in main memory\n");
                ret = -EIO;
                goto out_unmap_bo;
        }

        copy_cursor_image(src, dst, width, height, mask_size);

        flags = VBOX_MOUSE_POINTER_VISIBLE | VBOX_MOUSE_POINTER_SHAPE |
                VBOX_MOUSE_POINTER_ALPHA;
        ret = hgsmi_update_pointer_shape(vbox->guest_pool, flags,
                                         vbox->cursor_hot_x, vbox->cursor_hot_y,
                                         width, height, dst, data_size);
out_unmap_bo:
        ttm_bo_kunmap(&uobj_map);
out_unreserve_bo:
        vbox_bo_unreserve(bo);
out_unref_obj:
        drm_gem_object_put_unlocked(obj);

        return ret;
}

static int vbox_cursor_move(struct drm_crtc *crtc, int x, int y)
{
        struct vbox_private *vbox = crtc->dev->dev_private;
        u32 flags = VBOX_MOUSE_POINTER_VISIBLE |
            VBOX_MOUSE_POINTER_SHAPE | VBOX_MOUSE_POINTER_ALPHA;
        s32 crtc_x =
            vbox->single_framebuffer ? crtc->x : to_vbox_crtc(crtc)->x_hint;
        s32 crtc_y =
            vbox->single_framebuffer ? crtc->y : to_vbox_crtc(crtc)->y_hint;
        u32 host_x, host_y;
        u32 hot_x = 0;
        u32 hot_y = 0;
        int ret;

        /*
         * We compare these to unsigned later and don't
         * need to handle negative.
         */
        if (x + crtc_x < 0 || y + crtc_y < 0 || vbox->cursor_data_size == 0)
                return 0;

        ret = hgsmi_cursor_position(vbox->guest_pool, true, x + crtc_x,
                                    y + crtc_y, &host_x, &host_y);

        /*
         * The only reason we have vbox_cursor_move() is that some older clients
         * might use DRM_IOCTL_MODE_CURSOR instead of DRM_IOCTL_MODE_CURSOR2 and
         * use DRM_MODE_CURSOR_MOVE to set the hot-spot.
         *
         * However VirtualBox 5.0.20 and earlier has a bug causing it to return
         * 0,0 as host cursor location after a save and restore.
         *
         * To work around this we ignore a 0, 0 return, since missing the odd
         * time when it legitimately happens is not going to hurt much.
         */
        if (ret || (host_x == 0 && host_y == 0))
                return ret;

        if (x + crtc_x < host_x)
                hot_x = min(host_x - x - crtc_x, vbox->cursor_width);
        if (y + crtc_y < host_y)
                hot_y = min(host_y - y - crtc_y, vbox->cursor_height);

        if (hot_x == vbox->cursor_hot_x && hot_y == vbox->cursor_hot_y)
                return 0;

        vbox->cursor_hot_x = hot_x;
        vbox->cursor_hot_y = hot_y;

        return hgsmi_update_pointer_shape(vbox->guest_pool, flags,
                        hot_x, hot_y, vbox->cursor_width, vbox->cursor_height,
                        vbox->cursor_data, vbox->cursor_data_size);
}