/**************************************************************************
 *
 * Copyright © 2011 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_sou(x) \
        container_of(x, struct vmw_screen_object_unit, base.crtc)
#define vmw_encoder_to_sou(x) \
        container_of(x, struct vmw_screen_object_unit, base.encoder)
#define vmw_connector_to_sou(x) \
        container_of(x, struct vmw_screen_object_unit, base.connector)

struct vmw_screen_object_display {
        unsigned num_implicit;

        struct vmw_framebuffer *implicit_fb;
};

/**
 * Display unit using screen objects.
 */
struct vmw_screen_object_unit {
        struct vmw_display_unit base;

        unsigned long buffer_size; /**< Size of allocated buffer */
        struct vmw_dma_buffer *buffer; /**< Backing store buffer */

        bool defined;
        bool active_implicit;
};

static void vmw_sou_destroy(struct vmw_screen_object_unit *sou)
{
        vmw_display_unit_cleanup(&sou->base);
        kfree(sou);
}


/*
 * Screen Object Display Unit CRTC functions
 */

static void vmw_sou_crtc_destroy(struct drm_crtc *crtc)
{
        vmw_sou_destroy(vmw_crtc_to_sou(crtc));
}

static void vmw_sou_del_active(struct vmw_private *vmw_priv,
                              struct vmw_screen_object_unit *sou)
{
        struct vmw_screen_object_display *ld = vmw_priv->sou_priv;

        if (sou->active_implicit) {
                if (--(ld->num_implicit) == 0)
                        ld->implicit_fb = NULL;
                sou->active_implicit = false;
        }
}

static void vmw_sou_add_active(struct vmw_private *vmw_priv,
                              struct vmw_screen_object_unit *sou,
                              struct vmw_framebuffer *vfb)
{
        struct vmw_screen_object_display *ld = vmw_priv->sou_priv;

        BUG_ON(!ld->num_implicit && ld->implicit_fb);

        if (!sou->active_implicit && sou->base.is_implicit) {
                ld->implicit_fb = vfb;
                sou->active_implicit = true;
                ld->num_implicit++;
        }
}

/**
 * Send the fifo command to create a screen.
 */
static int vmw_sou_fifo_create(struct vmw_private *dev_priv,
                               struct vmw_screen_object_unit *sou,
                               uint32_t x, uint32_t y,
                               struct drm_display_mode *mode)
{
        size_t fifo_size;

        struct {
                struct {
                        uint32_t cmdType;
                } header;
                SVGAScreenObject obj;
        } *cmd;

        BUG_ON(!sou->buffer);

        fifo_size = sizeof(*cmd);
        cmd = vmw_fifo_reserve(dev_priv, fifo_size);
        /* The hardware has hung, nothing we can do about it here. */
        if (unlikely(cmd == NULL)) {
                DRM_ERROR("Fifo reserve failed.\n");
                return -ENOMEM;
        }

        memset(cmd, 0, fifo_size);
        cmd->header.cmdType = SVGA_CMD_DEFINE_SCREEN;
        cmd->obj.structSize = sizeof(SVGAScreenObject);
        cmd->obj.id = sou->base.unit;
        cmd->obj.flags = SVGA_SCREEN_HAS_ROOT |
                (sou->base.unit == 0 ? SVGA_SCREEN_IS_PRIMARY : 0);
        cmd->obj.size.width = mode->hdisplay;
        cmd->obj.size.height = mode->vdisplay;
        if (sou->base.is_implicit) {
                cmd->obj.root.x = x;
                cmd->obj.root.y = y;
        } else {
                cmd->obj.root.x = sou->base.gui_x;
                cmd->obj.root.y = sou->base.gui_y;
        }

        /* Ok to assume that buffer is pinned in vram */
        vmw_bo_get_guest_ptr(&sou->buffer->base, &cmd->obj.backingStore.ptr);
        cmd->obj.backingStore.pitch = mode->hdisplay * 4;

        vmw_fifo_commit(dev_priv, fifo_size);

        sou->defined = true;

        return 0;
}

/**
 * Send the fifo command to destroy a screen.
 */
static int vmw_sou_fifo_destroy(struct vmw_private *dev_priv,
                                struct vmw_screen_object_unit *sou)
{
        size_t fifo_size;
        int ret;

        struct {
                struct {
                        uint32_t cmdType;
                } header;
                SVGAFifoCmdDestroyScreen body;
        } *cmd;

        /* no need to do anything */
        if (unlikely(!sou->defined))
                return 0;

        fifo_size = sizeof(*cmd);
        cmd = vmw_fifo_reserve(dev_priv, fifo_size);
        /* the hardware has hung, nothing we can do about it here */
        if (unlikely(cmd == NULL)) {
                DRM_ERROR("Fifo reserve failed.\n");
                return -ENOMEM;
        }

        memset(cmd, 0, fifo_size);
        cmd->header.cmdType = SVGA_CMD_DESTROY_SCREEN;
        cmd->body.screenId = sou->base.unit;

        vmw_fifo_commit(dev_priv, fifo_size);

        /* Force sync */
        ret = vmw_fallback_wait(dev_priv, false, true, 0, false, 3*HZ);
        if (unlikely(ret != 0))
                DRM_ERROR("Failed to sync with HW");
        else
                sou->defined = false;

        return ret;
}

/**
 * Free the backing store.
 */
static void vmw_sou_backing_free(struct vmw_private *dev_priv,
                                 struct vmw_screen_object_unit *sou)
{
        struct ttm_buffer_object *bo;

        if (unlikely(sou->buffer == NULL))
                return;

        bo = &sou->buffer->base;
        ttm_bo_unref(&bo);
        sou->buffer = NULL;
        sou->buffer_size = 0;
}

/**
 * Allocate the backing store for the buffer.
 */
static int vmw_sou_backing_alloc(struct vmw_private *dev_priv,
                                 struct vmw_screen_object_unit *sou,
                                 unsigned long size)
{
        int ret;

        if (sou->buffer_size == size)
                return 0;

        if (sou->buffer)
                vmw_sou_backing_free(dev_priv, sou);

        sou->buffer = kzalloc(sizeof(*sou->buffer), GFP_KERNEL);
        if (unlikely(sou->buffer == NULL))
                return -ENOMEM;

        /* After we have alloced the backing store might not be able to
         * resume the overlays, this is preferred to failing to alloc.
         */
        vmw_overlay_pause_all(dev_priv);
        ret = vmw_dmabuf_init(dev_priv, sou->buffer, size,
                              &vmw_vram_ne_placement,
                              false, &vmw_dmabuf_bo_free);
        vmw_overlay_resume_all(dev_priv);

        if (unlikely(ret != 0))
                sou->buffer = NULL; /* vmw_dmabuf_init frees on error */
        else
                sou->buffer_size = size;

        return ret;
}

static int vmw_sou_crtc_set_config(struct drm_mode_set *set)
{
        struct vmw_private *dev_priv;
        struct vmw_screen_object_unit *sou;
        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;
        int ret = 0;

        if (!set)
                return -EINVAL;

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

        /* get the sou */
        crtc = set->crtc;
        sou = vmw_crtc_to_sou(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] != &sou->base.connector) {
                DRM_ERROR("connector doesn't match %p %p\n",
                        set->connectors[0], &sou->base.connector);
                return -EINVAL;
        }

        /* sou only supports one fb active at the time */
        if (sou->base.is_implicit &&
            dev_priv->sou_priv->implicit_fb && vfb &&
            !(dev_priv->sou_priv->num_implicit == 1 &&
              sou->active_implicit) &&
            dev_priv->sou_priv->implicit_fb != vfb) {
                DRM_ERROR("Multiple framebuffers not supported\n");
                return -EINVAL;
        }

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

        /* should we turn the crtc off */
        if (set->num_connectors == 0 || !set->mode || !set->fb) {
                ret = vmw_sou_fifo_destroy(dev_priv, sou);
                /* the hardware has hung don't do anything more */
                if (unlikely(ret != 0))
                        return ret;

                connector->encoder = NULL;
                encoder->crtc = NULL;
                crtc->fb = NULL;
                crtc->x = 0;
                crtc->y = 0;

                vmw_sou_del_active(dev_priv, sou);

                vmw_sou_backing_free(dev_priv, sou);

                return 0;
        }


        /* 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);

        if (mode->hdisplay != crtc->mode.hdisplay ||
            mode->vdisplay != crtc->mode.vdisplay) {
                /* no need to check if depth is different, because backing
                 * store depth is forced to 4 by the device.
                 */

                ret = vmw_sou_fifo_destroy(dev_priv, sou);
                /* the hardware has hung don't do anything more */
                if (unlikely(ret != 0))
                        return ret;

                vmw_sou_backing_free(dev_priv, sou);
        }

        if (!sou->buffer) {
                /* forced to depth 4 by the device */
                size_t size = mode->hdisplay * mode->vdisplay * 4;
                ret = vmw_sou_backing_alloc(dev_priv, sou, size);
                if (unlikely(ret != 0))
                        return ret;
        }

        ret = vmw_sou_fifo_create(dev_priv, sou, set->x, set->y, mode);
        if (unlikely(ret != 0)) {
                /*
                 * We are in a bit of a situation here, the hardware has
                 * hung and we may or may not have a buffer hanging of
                 * the screen object, best thing to do is not do anything
                 * if we where defined, if not just turn the crtc of.
                 * Not what userspace wants but it needs to htfu.
                 */
                if (sou->defined)
                        return ret;

                connector->encoder = NULL;
                encoder->crtc = NULL;
                crtc->fb = NULL;
                crtc->x = 0;
                crtc->y = 0;

                return ret;
        }

        vmw_sou_add_active(dev_priv, sou, vfb);

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

        return 0;
}

static struct drm_crtc_funcs vmw_screen_object_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_sou_crtc_destroy,
        .set_config = vmw_sou_crtc_set_config,
        .page_flip = vmw_du_page_flip,
};

/*
 * Screen Object Display Unit encoder functions
 */

static void vmw_sou_encoder_destroy(struct drm_encoder *encoder)
{
        vmw_sou_destroy(vmw_encoder_to_sou(encoder));
}

static struct drm_encoder_funcs vmw_screen_object_encoder_funcs = {
        .destroy = vmw_sou_encoder_destroy,
};

/*
 * Screen Object Display Unit connector functions
 */

static void vmw_sou_connector_destroy(struct drm_connector *connector)
{
        vmw_sou_destroy(vmw_connector_to_sou(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_sou_connector_destroy,
};

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

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

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

        sou->active_implicit = false;

        sou->base.pref_active = (unit == 0);
        sou->base.pref_width = dev_priv->initial_width;
        sou->base.pref_height = dev_priv->initial_height;
        sou->base.pref_mode = NULL;
        sou->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_screen_object_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_screen_object_crtc_funcs);

        drm_mode_crtc_set_gamma_size(crtc, 256);

        drm_object_attach_property(&connector->base,
                                      dev->mode_config.dirty_info_property,
                                      1);

        return 0;
}

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

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

        if (!(dev_priv->capabilities & SVGA_CAP_SCREEN_OBJECT_2)) {
                DRM_INFO("Not using screen objects,"
                         " missing cap SCREEN_OBJECT_2\n");
                return -ENOSYS;
        }

        ret = -ENOMEM;
        dev_priv->sou_priv = kmalloc(sizeof(*dev_priv->sou_priv), GFP_KERNEL);
        if (unlikely(!dev_priv->sou_priv))
                goto err_no_mem;

        dev_priv->sou_priv->num_implicit = 0;
        dev_priv->sou_priv->implicit_fb = NULL;

        ret = drm_vblank_init(dev, VMWGFX_NUM_DISPLAY_UNITS);
        if (unlikely(ret != 0))
                goto err_free;

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

        for (i = 0; i < VMWGFX_NUM_DISPLAY_UNITS; ++i)
                vmw_sou_init(dev_priv, i);

        DRM_INFO("Screen objects system initialized\n");

        return 0;

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

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

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

        drm_vblank_cleanup(dev);

        kfree(dev_priv->sou_priv);

        return 0;
}

/**
 * Returns if this unit can be page flipped.
 * Must be called with the mode_config mutex held.
 */
bool vmw_kms_screen_object_flippable(struct vmw_private *dev_priv,
                                     struct drm_crtc *crtc)
{
        struct vmw_screen_object_unit *sou = vmw_crtc_to_sou(crtc);

        if (!sou->base.is_implicit)
                return true;

        if (dev_priv->sou_priv->num_implicit != 1)
                return false;

        return true;
}

/**
 * Update the implicit fb to the current fb of this crtc.
 * Must be called with the mode_config mutex held.
 */
void vmw_kms_screen_object_update_implicit_fb(struct vmw_private *dev_priv,
                                              struct drm_crtc *crtc)
{
        struct vmw_screen_object_unit *sou = vmw_crtc_to_sou(crtc);

        BUG_ON(!sou->base.is_implicit);

        dev_priv->sou_priv->implicit_fb =
                vmw_framebuffer_to_vfb(sou->base.crtc.fb);
}