/**************************************************************************
 *
 * Copyright © 2009 VMware, Inc., Palo Alto, CA., USA
 * All Rights Reserved.
 *
 * 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 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 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.
 *
 **************************************************************************/

#include "vmwgfx_kms.h"


#define vmw_crtc_to_ldu(x) \
        container_of(x, struct vmw_legacy_display_unit, base.crtc)
#define vmw_encoder_to_ldu(x) \
        container_of(x, struct vmw_legacy_display_unit, base.encoder)
#define vmw_connector_to_ldu(x) \
        container_of(x, struct vmw_legacy_display_unit, base.connector)

struct vmw_legacy_display {
        struct list_head active;

        unsigned num_active;
        unsigned last_num_active;

        struct vmw_framebuffer *fb;
};

/**
 * Display unit using the legacy register interface.
 */
struct vmw_legacy_display_unit {
        struct vmw_display_unit base;

        struct list_head active;
};

static void vmw_ldu_destroy(struct vmw_legacy_display_unit *ldu)
{
        list_del_init(&ldu->active);
        vmw_display_unit_cleanup(&ldu->base);
        kfree(ldu);
}


/*
 * Legacy Display Unit CRTC functions
 */

static void vmw_ldu_crtc_destroy(struct drm_crtc *crtc)
{
        vmw_ldu_destroy(vmw_crtc_to_ldu(crtc));
}

static int vmw_ldu_commit_list(struct vmw_private *dev_priv)
{
        struct vmw_legacy_display *lds = dev_priv->ldu_priv;
        struct vmw_legacy_display_unit *entry;
        struct vmw_display_unit *du = NULL;
        struct drm_framebuffer *fb = NULL;
        struct drm_crtc *crtc = NULL;
        int i = 0, ret;

        /* If there is no display topology the host just assumes
         * that the guest will set the same layout as the host.
         */
        if (!(dev_priv->capabilities & SVGA_CAP_DISPLAY_TOPOLOGY)) {
                int w = 0, h = 0;
                list_for_each_entry(entry, &lds->active, active) {
                        crtc = &entry->base.crtc;
                        w = max(w, crtc->x + crtc->mode.hdisplay);
                        h = max(h, crtc->y + crtc->mode.vdisplay);
                        i++;
                }

                if (crtc == NULL)
                        return 0;
                fb = entry->base.crtc.fb;

                return vmw_kms_write_svga(dev_priv, w, h, fb->pitches[0],
                                          fb->bits_per_pixel, fb->depth);
        }

        if (!list_empty(&lds->active)) {
                entry = list_entry(lds->active.next, typeof(*entry), active);
                fb = entry->base.crtc.fb;

                vmw_kms_write_svga(dev_priv, fb->width, fb->height, fb->pitches[0],
                                   fb->bits_per_pixel, fb->depth);
        }

        /* Make sure we always show something. */
        vmw_write(dev_priv, SVGA_REG_NUM_GUEST_DISPLAYS,
                  lds->num_active ? lds->num_active : 1);

        i = 0;
        list_for_each_entry(entry, &lds->active, active) {
                crtc = &entry->base.crtc;

                vmw_write(dev_priv, SVGA_REG_DISPLAY_ID, i);
                vmw_write(dev_priv, SVGA_REG_DISPLAY_IS_PRIMARY, !i);
                vmw_write(dev_priv, SVGA_REG_DISPLAY_POSITION_X, crtc->x);
                vmw_write(dev_priv, SVGA_REG_DISPLAY_POSITION_Y, crtc->y);
                vmw_write(dev_priv, SVGA_REG_DISPLAY_WIDTH, crtc->mode.hdisplay);
                vmw_write(dev_priv, SVGA_REG_DISPLAY_HEIGHT, crtc->mode.vdisplay);
                vmw_write(dev_priv, SVGA_REG_DISPLAY_ID, SVGA_ID_INVALID);

                i++;
        }

        BUG_ON(i != lds->num_active);

        lds->last_num_active = lds->num_active;


        /* Find the first du with a cursor. */
        list_for_each_entry(entry, &lds->active, active) {
                du = &entry->base;

                if (!du->cursor_dmabuf)
                        continue;

                ret = vmw_cursor_update_dmabuf(dev_priv,
                                               du->cursor_dmabuf,
                                               64, 64,
                                               du->hotspot_x,
                                               du->hotspot_y);
                if (ret == 0)
                        break;

                DRM_ERROR("Could not update cursor image\n");
        }

        return 0;
}

static int vmw_ldu_del_active(struct vmw_private *vmw_priv,
                              struct vmw_legacy_display_unit *ldu)
{
        struct vmw_legacy_display *ld = vmw_priv->ldu_priv;
        if (list_empty(&ldu->active))
                return 0;

        /* Must init otherwise list_empty(&ldu->active) will not work. */
        list_del_init(&ldu->active);
        if (--(ld->num_active) == 0) {
                BUG_ON(!ld->fb);
                if (ld->fb->unpin)
                        ld->fb->unpin(ld->fb);
                ld->fb = NULL;
        }

        return 0;
}

static int vmw_ldu_add_active(struct vmw_private *vmw_priv,
                              struct vmw_legacy_display_unit *ldu,
                              struct vmw_framebuffer *vfb)
{
        struct vmw_legacy_display *ld = vmw_priv->ldu_priv;
        struct vmw_legacy_display_unit *entry;
        struct list_head *at;

        BUG_ON(!ld->num_active && ld->fb);
        if (vfb != ld->fb) {
                if (ld->fb && ld->fb->unpin)
                        ld->fb->unpin(ld->fb);
                if (vfb->pin)
                        vfb->pin(vfb);
                ld->fb = vfb;
        }

        if (!list_empty(&ldu->active))
                return 0;

        at = &ld->active;
        list_for_each_entry(entry, &ld->active, active) {
                if (entry->base.unit > ldu->base.unit)
                        break;

                at = &entry->active;
        }

        list_add(&ldu->active, at);

        ld->num_active++;

        return 0;
}

static int vmw_ldu_crtc_set_config(struct drm_mode_set *set)
{
        struct vmw_private *dev_priv;
        struct vmw_legacy_display_unit *ldu;
        struct drm_connector *connector;
        struct drm_display_mode *mode;
        struct drm_encoder *encoder;
        struct vmw_framebuffer *vfb;
        struct drm_framebuffer *fb;
        struct drm_crtc *crtc;

        if (!set)
                return -EINVAL;

        if (!set->crtc)
                return -EINVAL;

        /* get the ldu */
        crtc = set->crtc;
        ldu = vmw_crtc_to_ldu(crtc);
        vfb = set->fb ? vmw_framebuffer_to_vfb(set->fb) : NULL;
        dev_priv = vmw_priv(crtc->dev);

        if (set->num_connectors > 1) {
                DRM_ERROR("to many connectors\n");
                return -EINVAL;
        }

        if (set->num_connectors == 1 &&
            set->connectors[0] != &ldu->base.connector) {
                DRM_ERROR("connector doesn't match %p %p\n",
                        set->connectors[0], &ldu->base.connector);
                return -EINVAL;
        }

        /* ldu only supports one fb active at the time */
        if (dev_priv->ldu_priv->fb && vfb &&
            !(dev_priv->ldu_priv->num_active == 1 &&
              !list_empty(&ldu->active)) &&
            dev_priv->ldu_priv->fb != vfb) {
                DRM_ERROR("Multiple framebuffers not supported\n");
                return -EINVAL;
        }

        /* since they always map one to one these are safe */
        connector = &ldu->base.connector;
        encoder = &ldu->base.encoder;

        /* should we turn the crtc off? */
        if (set->num_connectors == 0 || !set->mode || !set->fb) {

                connector->encoder = NULL;
                encoder->crtc = NULL;
                crtc->fb = NULL;

                vmw_ldu_del_active(dev_priv, ldu);

                return vmw_ldu_commit_list(dev_priv);
        }


        /* we now know we want to set a mode */
        mode = set->mode;
        fb = set->fb;

        if (set->x + mode->hdisplay > fb->width ||
            set->y + mode->vdisplay > fb->height) {
                DRM_ERROR("set outside of framebuffer\n");
                return -EINVAL;
        }

        vmw_fb_off(dev_priv);

        crtc->fb = fb;
        encoder->crtc = crtc;
        connector->encoder = encoder;
        crtc->x = set->x;
        crtc->y = set->y;
        crtc->mode = *mode;

        vmw_ldu_add_active(dev_priv, ldu, vfb);

        return vmw_ldu_commit_list(dev_priv);
}

static struct drm_crtc_funcs vmw_legacy_crtc_funcs = {
        .save = vmw_du_crtc_save,
        .restore = vmw_du_crtc_restore,
        .cursor_set = vmw_du_crtc_cursor_set,
        .cursor_move = vmw_du_crtc_cursor_move,
        .gamma_set = vmw_du_crtc_gamma_set,
        .destroy = vmw_ldu_crtc_destroy,
        .set_config = vmw_ldu_crtc_set_config,
};


/*
 * Legacy Display Unit encoder functions
 */

static void vmw_ldu_encoder_destroy(struct drm_encoder *encoder)
{
        vmw_ldu_destroy(vmw_encoder_to_ldu(encoder));
}

static struct drm_encoder_funcs vmw_legacy_encoder_funcs = {
        .destroy = vmw_ldu_encoder_destroy,
};

/*
 * Legacy Display Unit connector functions
 */

static void vmw_ldu_connector_destroy(struct drm_connector *connector)
{
        vmw_ldu_destroy(vmw_connector_to_ldu(connector));
}

static struct drm_connector_funcs vmw_legacy_connector_funcs = {
        .dpms = vmw_du_connector_dpms,
        .save = vmw_du_connector_save,
        .restore = vmw_du_connector_restore,
        .detect = vmw_du_connector_detect,
        .fill_modes = vmw_du_connector_fill_modes,
        .set_property = vmw_du_connector_set_property,
        .destroy = vmw_ldu_connector_destroy,
};

static int vmw_ldu_init(struct vmw_private *dev_priv, unsigned unit)
{
        struct vmw_legacy_display_unit *ldu;
        struct drm_device *dev = dev_priv->dev;
        struct drm_connector *connector;
        struct drm_encoder *encoder;
        struct drm_crtc *crtc;

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

        ldu->base.unit = unit;
        crtc = &ldu->base.crtc;
        encoder = &ldu->base.encoder;
        connector = &ldu->base.connector;

        INIT_LIST_HEAD(&ldu->active);

        ldu->base.pref_active = (unit == 0);
        ldu->base.pref_width = dev_priv->initial_width;
        ldu->base.pref_height = dev_priv->initial_height;
        ldu->base.pref_mode = NULL;
        ldu->base.is_implicit = true;

        drm_connector_init(dev, connector, &vmw_legacy_connector_funcs,
                           DRM_MODE_CONNECTOR_VIRTUAL);
        connector->status = vmw_du_connector_detect(connector, true);

        drm_encoder_init(dev, encoder, &vmw_legacy_encoder_funcs,
                         DRM_MODE_ENCODER_VIRTUAL);
        drm_mode_connector_attach_encoder(connector, encoder);
        encoder->possible_crtcs = (1 << unit);
        encoder->possible_clones = 0;

        drm_crtc_init(dev, crtc, &vmw_legacy_crtc_funcs);

        drm_mode_crtc_set_gamma_size(crtc, 256);

        drm_connector_attach_property(connector,
                                      dev->mode_config.dirty_info_property,
                                      1);

        return 0;
}

int vmw_kms_init_legacy_display_system(struct vmw_private *dev_priv)
{
        struct drm_device *dev = dev_priv->dev;
        int i, ret;

        if (dev_priv->ldu_priv) {
                DRM_INFO("ldu system already on\n");
                return -EINVAL;
        }

        dev_priv->ldu_priv = kmalloc(sizeof(*dev_priv->ldu_priv), GFP_KERNEL);
        if (!dev_priv->ldu_priv)
                return -ENOMEM;

        INIT_LIST_HEAD(&dev_priv->ldu_priv->active);
        dev_priv->ldu_priv->num_active = 0;
        dev_priv->ldu_priv->last_num_active = 0;
        dev_priv->ldu_priv->fb = NULL;

        /* for old hardware without multimon only enable one display */
        if (dev_priv->capabilities & SVGA_CAP_MULTIMON)
                ret = drm_vblank_init(dev, VMWGFX_NUM_DISPLAY_UNITS);
        else
                ret = drm_vblank_init(dev, 1);
        if (ret != 0)
                goto err_free;

        ret = drm_mode_create_dirty_info_property(dev);
        if (ret != 0)
                goto err_vblank_cleanup;

        if (dev_priv->capabilities & SVGA_CAP_MULTIMON)
                for (i = 0; i < VMWGFX_NUM_DISPLAY_UNITS; ++i)
                        vmw_ldu_init(dev_priv, i);
        else
                vmw_ldu_init(dev_priv, 0);

        return 0;

err_vblank_cleanup:
        drm_vblank_cleanup(dev);
err_free:
        kfree(dev_priv->ldu_priv);
        dev_priv->ldu_priv = NULL;
        return ret;
}

int vmw_kms_close_legacy_display_system(struct vmw_private *dev_priv)
{
        struct drm_device *dev = dev_priv->dev;

        if (!dev_priv->ldu_priv)
                return -ENOSYS;

        drm_vblank_cleanup(dev);

        BUG_ON(!list_empty(&dev_priv->ldu_priv->active));

        kfree(dev_priv->ldu_priv);

        return 0;
}