// SPDX-License-Identifier: GPL-2.0 OR MIT
/**************************************************************************
 *
 * Copyright 2009-2023 VMware, Inc., Palo Alto, CA., USA
 *
 * 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_bo.h"
#include "vmwgfx_drv.h"

#include "device_include/svga_overlay.h"
#include "device_include/svga_escape.h"

#include <drm/ttm/ttm_placement.h>

#define VMW_MAX_NUM_STREAMS 1
#define VMW_OVERLAY_CAP_MASK (SVGA_FIFO_CAP_VIDEO | SVGA_FIFO_CAP_ESCAPE)

struct vmw_stream {
        struct vmw_bo *buf;
        bool claimed;
        bool paused;
        struct drm_vmw_control_stream_arg saved;
};

/*
 * Overlay control
 */
struct vmw_overlay {
        /*
         * Each stream is a single overlay. In Xv these are called ports.
         */
        struct mutex mutex;
        struct vmw_stream stream[VMW_MAX_NUM_STREAMS];
};

struct vmw_escape_header {
        uint32_t cmd;
        SVGAFifoCmdEscape body;
};

struct vmw_escape_video_flush {
        struct vmw_escape_header escape;
        SVGAEscapeVideoFlush flush;
};

static inline void fill_escape(struct vmw_escape_header *header,
                               uint32_t size)
{
        header->cmd = SVGA_CMD_ESCAPE;
        header->body.nsid = SVGA_ESCAPE_NSID_VMWARE;
        header->body.size = size;
}

static inline void fill_flush(struct vmw_escape_video_flush *cmd,
                              uint32_t stream_id)
{
        fill_escape(&cmd->escape, sizeof(cmd->flush));
        cmd->flush.cmdType = SVGA_ESCAPE_VMWARE_VIDEO_FLUSH;
        cmd->flush.streamId = stream_id;
}

/*
 * Send put command to hw.
 *
 * Returns
 * -ERESTARTSYS if interrupted by a signal.
 */
static int vmw_overlay_send_put(struct vmw_private *dev_priv,
                                struct vmw_bo *buf,
                                struct drm_vmw_control_stream_arg *arg,
                                bool interruptible)
{
        struct vmw_escape_video_flush *flush;
        size_t fifo_size;
        bool have_so = (dev_priv->active_display_unit != vmw_du_legacy);
        int i, num_items;
        SVGAGuestPtr ptr;

        struct {
                struct vmw_escape_header escape;
                struct {
                        uint32_t cmdType;
                        uint32_t streamId;
                } header;
        } *cmds;
        struct {
                uint32_t registerId;
                uint32_t value;
        } *items;

        /* defines are a index needs + 1 */
        if (have_so)
                num_items = SVGA_VIDEO_DST_SCREEN_ID + 1;
        else
                num_items = SVGA_VIDEO_PITCH_3 + 1;

        fifo_size = sizeof(*cmds) + sizeof(*flush) + sizeof(*items) * num_items;

        cmds = VMW_CMD_RESERVE(dev_priv, fifo_size);
        /* hardware has hung, can't do anything here */
        if (!cmds)
                return -ENOMEM;

        items = (typeof(items))&cmds[1];
        flush = (struct vmw_escape_video_flush *)&items[num_items];

        /* the size is header + number of items */
        fill_escape(&cmds->escape, sizeof(*items) * (num_items + 1));

        cmds->header.cmdType = SVGA_ESCAPE_VMWARE_VIDEO_SET_REGS;
        cmds->header.streamId = arg->stream_id;

        /* the IDs are neatly numbered */
        for (i = 0; i < num_items; i++)
                items[i].registerId = i;

        vmw_bo_get_guest_ptr(&buf->tbo, &ptr);
        ptr.offset += arg->offset;

        items[SVGA_VIDEO_ENABLED].value     = true;
        items[SVGA_VIDEO_FLAGS].value       = arg->flags;
        items[SVGA_VIDEO_DATA_OFFSET].value = ptr.offset;
        items[SVGA_VIDEO_FORMAT].value      = arg->format;
        items[SVGA_VIDEO_COLORKEY].value    = arg->color_key;
        items[SVGA_VIDEO_SIZE].value        = arg->size;
        items[SVGA_VIDEO_WIDTH].value       = arg->width;
        items[SVGA_VIDEO_HEIGHT].value      = arg->height;
        items[SVGA_VIDEO_SRC_X].value       = arg->src.x;
        items[SVGA_VIDEO_SRC_Y].value       = arg->src.y;
        items[SVGA_VIDEO_SRC_WIDTH].value   = arg->src.w;
        items[SVGA_VIDEO_SRC_HEIGHT].value  = arg->src.h;
        items[SVGA_VIDEO_DST_X].value       = arg->dst.x;
        items[SVGA_VIDEO_DST_Y].value       = arg->dst.y;
        items[SVGA_VIDEO_DST_WIDTH].value   = arg->dst.w;
        items[SVGA_VIDEO_DST_HEIGHT].value  = arg->dst.h;
        items[SVGA_VIDEO_PITCH_1].value     = arg->pitch[0];
        items[SVGA_VIDEO_PITCH_2].value     = arg->pitch[1];
        items[SVGA_VIDEO_PITCH_3].value     = arg->pitch[2];
        if (have_so) {
                items[SVGA_VIDEO_DATA_GMRID].value    = ptr.gmrId;
                items[SVGA_VIDEO_DST_SCREEN_ID].value = SVGA_ID_INVALID;
        }

        fill_flush(flush, arg->stream_id);

        vmw_cmd_commit(dev_priv, fifo_size);

        return 0;
}

/*
 * Send stop command to hw.
 *
 * Returns
 * -ERESTARTSYS if interrupted by a signal.
 */
static int vmw_overlay_send_stop(struct vmw_private *dev_priv,
                                 uint32_t stream_id,
                                 bool interruptible)
{
        struct {
                struct vmw_escape_header escape;
                SVGAEscapeVideoSetRegs body;
                struct vmw_escape_video_flush flush;
        } *cmds;
        int ret;

        for (;;) {
                cmds = VMW_CMD_RESERVE(dev_priv, sizeof(*cmds));
                if (cmds)
                        break;

                ret = vmw_fallback_wait(dev_priv, false, true, 0,
                                        interruptible, 3*HZ);
                if (interruptible && ret == -ERESTARTSYS)
                        return ret;
                else
                        BUG_ON(ret != 0);
        }

        fill_escape(&cmds->escape, sizeof(cmds->body));
        cmds->body.header.cmdType = SVGA_ESCAPE_VMWARE_VIDEO_SET_REGS;
        cmds->body.header.streamId = stream_id;
        cmds->body.items[0].registerId = SVGA_VIDEO_ENABLED;
        cmds->body.items[0].value = false;
        fill_flush(&cmds->flush, stream_id);

        vmw_cmd_commit(dev_priv, sizeof(*cmds));

        return 0;
}

/*
 * Move a buffer to vram or gmr if @pin is set, else unpin the buffer.
 *
 * With the introduction of screen objects buffers could now be
 * used with GMRs instead of being locked to vram.
 */
static int vmw_overlay_move_buffer(struct vmw_private *dev_priv,
                                   struct vmw_bo *buf,
                                   bool pin, bool inter)
{
        if (!pin)
                return vmw_bo_unpin(dev_priv, buf, inter);

        if (dev_priv->active_display_unit == vmw_du_legacy)
                return vmw_bo_pin_in_vram(dev_priv, buf, inter);

        return vmw_bo_pin_in_vram_or_gmr(dev_priv, buf, inter);
}

/*
 * Stop or pause a stream.
 *
 * If the stream is paused the no evict flag is removed from the buffer
 * but left in vram. This allows for instance mode_set to evict it
 * should it need to.
 *
 * The caller must hold the overlay lock.
 *
 * @stream_id which stream to stop/pause.
 * @pause true to pause, false to stop completely.
 */
static int vmw_overlay_stop(struct vmw_private *dev_priv,
                            uint32_t stream_id, bool pause,
                            bool interruptible)
{
        struct vmw_overlay *overlay = dev_priv->overlay_priv;
        struct vmw_stream *stream = &overlay->stream[stream_id];
        int ret;

        /* no buffer attached the stream is completely stopped */
        if (!stream->buf)
                return 0;

        /* If the stream is paused this is already done */
        if (!stream->paused) {
                ret = vmw_overlay_send_stop(dev_priv, stream_id,
                                            interruptible);
                if (ret)
                        return ret;

                /* We just remove the NO_EVICT flag so no -ENOMEM */
                ret = vmw_overlay_move_buffer(dev_priv, stream->buf, false,
                                              interruptible);
                if (interruptible && ret == -ERESTARTSYS)
                        return ret;
                else
                        BUG_ON(ret != 0);
        }

        if (!pause) {
                vmw_bo_unreference(&stream->buf);
                stream->paused = false;
        } else {
                stream->paused = true;
        }

        return 0;
}

/*
 * Update a stream and send any put or stop fifo commands needed.
 *
 * The caller must hold the overlay lock.
 *
 * Returns
 * -ENOMEM if buffer doesn't fit in vram.
 * -ERESTARTSYS if interrupted.
 */
static int vmw_overlay_update_stream(struct vmw_private *dev_priv,
                                     struct vmw_bo *buf,
                                     struct drm_vmw_control_stream_arg *arg,
                                     bool interruptible)
{
        struct vmw_overlay *overlay = dev_priv->overlay_priv;
        struct vmw_stream *stream = &overlay->stream[arg->stream_id];
        int ret = 0;

        if (!buf)
                return -EINVAL;

        DRM_DEBUG("   %s: old %p, new %p, %spaused\n", __func__,
                  stream->buf, buf, stream->paused ? "" : "not ");

        if (stream->buf != buf) {
                ret = vmw_overlay_stop(dev_priv, arg->stream_id,
                                       false, interruptible);
                if (ret)
                        return ret;
        } else if (!stream->paused) {
                /* If the buffers match and not paused then just send
                 * the put command, no need to do anything else.
                 */
                ret = vmw_overlay_send_put(dev_priv, buf, arg, interruptible);
                if (ret == 0)
                        stream->saved = *arg;
                else
                        BUG_ON(!interruptible);

                return ret;
        }

        /* We don't start the old stream if we are interrupted.
         * Might return -ENOMEM if it can't fit the buffer in vram.
         */
        ret = vmw_overlay_move_buffer(dev_priv, buf, true, interruptible);
        if (ret)
                return ret;

        ret = vmw_overlay_send_put(dev_priv, buf, arg, interruptible);
        if (ret) {
                /* This one needs to happen no matter what. We only remove
                 * the NO_EVICT flag so this is safe from -ENOMEM.
                 */
                BUG_ON(vmw_overlay_move_buffer(dev_priv, buf, false, false)
                       != 0);
                return ret;
        }

        if (stream->buf != buf)
                stream->buf = vmw_bo_reference(buf);
        stream->saved = *arg;
        /* stream is no longer stopped/paused */
        stream->paused = false;

        return 0;
}

/*
 * Try to resume all paused streams.
 *
 * Used by the kms code after moving a new scanout buffer to vram.
 *
 * Takes the overlay lock.
 */
int vmw_overlay_resume_all(struct vmw_private *dev_priv)
{
        struct vmw_overlay *overlay = dev_priv->overlay_priv;
        int i, ret;

        if (!overlay)
                return 0;

        mutex_lock(&overlay->mutex);

        for (i = 0; i < VMW_MAX_NUM_STREAMS; i++) {
                struct vmw_stream *stream = &overlay->stream[i];
                if (!stream->paused)
                        continue;

                ret = vmw_overlay_update_stream(dev_priv, stream->buf,
                                                &stream->saved, false);
                if (ret != 0)
                        DRM_INFO("%s: *warning* failed to resume stream %i\n",
                                 __func__, i);
        }

        mutex_unlock(&overlay->mutex);

        return 0;
}

/*
 * Pauses all active streams.
 *
 * Used by the kms code when moving a new scanout buffer to vram.
 *
 * Takes the overlay lock.
 */
int vmw_overlay_pause_all(struct vmw_private *dev_priv)
{
        struct vmw_overlay *overlay = dev_priv->overlay_priv;
        int i, ret;

        if (!overlay)
                return 0;

        mutex_lock(&overlay->mutex);

        for (i = 0; i < VMW_MAX_NUM_STREAMS; i++) {
                if (overlay->stream[i].paused)
                        DRM_INFO("%s: *warning* stream %i already paused\n",
                                 __func__, i);
                ret = vmw_overlay_stop(dev_priv, i, true, false);
                WARN_ON(ret != 0);
        }

        mutex_unlock(&overlay->mutex);

        return 0;
}


static bool vmw_overlay_available(const struct vmw_private *dev_priv)
{
        return (dev_priv->overlay_priv != NULL &&
                ((vmw_fifo_caps(dev_priv) & VMW_OVERLAY_CAP_MASK) ==
                 VMW_OVERLAY_CAP_MASK));
}

int vmw_overlay_ioctl(struct drm_device *dev, void *data,
                      struct drm_file *file_priv)
{
        struct ttm_object_file *tfile = vmw_fpriv(file_priv)->tfile;
        struct vmw_private *dev_priv = vmw_priv(dev);
        struct vmw_overlay *overlay = dev_priv->overlay_priv;
        struct drm_vmw_control_stream_arg *arg =
            (struct drm_vmw_control_stream_arg *)data;
        struct vmw_bo *buf;
        struct vmw_resource *res;
        int ret;

        if (!vmw_overlay_available(dev_priv))
                return -ENOSYS;

        ret = vmw_user_stream_lookup(dev_priv, tfile, &arg->stream_id, &res);
        if (ret)
                return ret;

        mutex_lock(&overlay->mutex);

        if (!arg->enabled) {
                ret = vmw_overlay_stop(dev_priv, arg->stream_id, false, true);
                goto out_unlock;
        }

        ret = vmw_user_bo_lookup(file_priv, arg->handle, &buf);
        if (ret)
                goto out_unlock;

        ret = vmw_overlay_update_stream(dev_priv, buf, arg, true);

        vmw_user_bo_unref(&buf);

out_unlock:
        mutex_unlock(&overlay->mutex);
        vmw_resource_unreference(&res);

        return ret;
}

int vmw_overlay_num_overlays(struct vmw_private *dev_priv)
{
        if (!vmw_overlay_available(dev_priv))
                return 0;

        return VMW_MAX_NUM_STREAMS;
}

int vmw_overlay_num_free_overlays(struct vmw_private *dev_priv)
{
        struct vmw_overlay *overlay = dev_priv->overlay_priv;
        int i, k;

        if (!vmw_overlay_available(dev_priv))
                return 0;

        mutex_lock(&overlay->mutex);

        for (i = 0, k = 0; i < VMW_MAX_NUM_STREAMS; i++)
                if (!overlay->stream[i].claimed)
                        k++;

        mutex_unlock(&overlay->mutex);

        return k;
}

int vmw_overlay_claim(struct vmw_private *dev_priv, uint32_t *out)
{
        struct vmw_overlay *overlay = dev_priv->overlay_priv;
        int i;

        if (!overlay)
                return -ENOSYS;

        mutex_lock(&overlay->mutex);

        for (i = 0; i < VMW_MAX_NUM_STREAMS; i++) {

                if (overlay->stream[i].claimed)
                        continue;

                overlay->stream[i].claimed = true;
                *out = i;
                mutex_unlock(&overlay->mutex);
                return 0;
        }

        mutex_unlock(&overlay->mutex);
        return -ESRCH;
}

int vmw_overlay_unref(struct vmw_private *dev_priv, uint32_t stream_id)
{
        struct vmw_overlay *overlay = dev_priv->overlay_priv;

        BUG_ON(stream_id >= VMW_MAX_NUM_STREAMS);

        if (!overlay)
                return -ENOSYS;

        mutex_lock(&overlay->mutex);

        WARN_ON(!overlay->stream[stream_id].claimed);
        vmw_overlay_stop(dev_priv, stream_id, false, false);
        overlay->stream[stream_id].claimed = false;

        mutex_unlock(&overlay->mutex);
        return 0;
}

int vmw_overlay_init(struct vmw_private *dev_priv)
{
        struct vmw_overlay *overlay;
        int i;

        if (dev_priv->overlay_priv)
                return -EINVAL;

        overlay = kzalloc_obj(*overlay);
        if (!overlay)
                return -ENOMEM;

        mutex_init(&overlay->mutex);
        for (i = 0; i < VMW_MAX_NUM_STREAMS; i++) {
                overlay->stream[i].buf = NULL;
                overlay->stream[i].paused = false;
                overlay->stream[i].claimed = false;
        }

        dev_priv->overlay_priv = overlay;

        return 0;
}

int vmw_overlay_close(struct vmw_private *dev_priv)
{
        struct vmw_overlay *overlay = dev_priv->overlay_priv;
        bool forgotten_buffer = false;
        int i;

        if (!overlay)
                return -ENOSYS;

        for (i = 0; i < VMW_MAX_NUM_STREAMS; i++) {
                if (overlay->stream[i].buf) {
                        forgotten_buffer = true;
                        vmw_overlay_stop(dev_priv, i, false, false);
                }
        }

        WARN_ON(forgotten_buffer);

        dev_priv->overlay_priv = NULL;
        kfree(overlay);

        return 0;
}