/**************************************************************************
 *
 * 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_drv.h"
#include <drm/drmP.h>
#include <drm/ttm/ttm_placement.h>

bool vmw_fifo_have_3d(struct vmw_private *dev_priv)
{
        __le32 __iomem *fifo_mem = dev_priv->mmio_virt;
        uint32_t fifo_min, hwversion;
        const struct vmw_fifo_state *fifo = &dev_priv->fifo;

        if (!(dev_priv->capabilities & SVGA_CAP_EXTENDED_FIFO))
                return false;

        fifo_min = ioread32(fifo_mem  + SVGA_FIFO_MIN);
        if (fifo_min <= SVGA_FIFO_3D_HWVERSION * sizeof(unsigned int))
                return false;

        hwversion = ioread32(fifo_mem +
                             ((fifo->capabilities &
                               SVGA_FIFO_CAP_3D_HWVERSION_REVISED) ?
                              SVGA_FIFO_3D_HWVERSION_REVISED :
                              SVGA_FIFO_3D_HWVERSION));

        if (hwversion == 0)
                return false;

        if (hwversion < SVGA3D_HWVERSION_WS8_B1)
                return false;

        /* Non-Screen Object path does not support surfaces */
        if (!dev_priv->sou_priv)
                return false;

        return true;
}

bool vmw_fifo_have_pitchlock(struct vmw_private *dev_priv)
{
        __le32 __iomem *fifo_mem = dev_priv->mmio_virt;
        uint32_t caps;

        if (!(dev_priv->capabilities & SVGA_CAP_EXTENDED_FIFO))
                return false;

        caps = ioread32(fifo_mem + SVGA_FIFO_CAPABILITIES);
        if (caps & SVGA_FIFO_CAP_PITCHLOCK)
                return true;

        return false;
}

int vmw_fifo_init(struct vmw_private *dev_priv, struct vmw_fifo_state *fifo)
{
        __le32 __iomem *fifo_mem = dev_priv->mmio_virt;
        uint32_t max;
        uint32_t min;
        uint32_t dummy;

        fifo->static_buffer_size = VMWGFX_FIFO_STATIC_SIZE;
        fifo->static_buffer = vmalloc(fifo->static_buffer_size);
        if (unlikely(fifo->static_buffer == NULL))
                return -ENOMEM;

        fifo->dynamic_buffer = NULL;
        fifo->reserved_size = 0;
        fifo->using_bounce_buffer = false;

        mutex_init(&fifo->fifo_mutex);
        init_rwsem(&fifo->rwsem);

        /*
         * Allow mapping the first page read-only to user-space.
         */

        DRM_INFO("width %d\n", vmw_read(dev_priv, SVGA_REG_WIDTH));
        DRM_INFO("height %d\n", vmw_read(dev_priv, SVGA_REG_HEIGHT));
        DRM_INFO("bpp %d\n", vmw_read(dev_priv, SVGA_REG_BITS_PER_PIXEL));

        mutex_lock(&dev_priv->hw_mutex);
        dev_priv->enable_state = vmw_read(dev_priv, SVGA_REG_ENABLE);
        dev_priv->config_done_state = vmw_read(dev_priv, SVGA_REG_CONFIG_DONE);
        dev_priv->traces_state = vmw_read(dev_priv, SVGA_REG_TRACES);
        vmw_write(dev_priv, SVGA_REG_ENABLE, 1);

        min = 4;
        if (dev_priv->capabilities & SVGA_CAP_EXTENDED_FIFO)
                min = vmw_read(dev_priv, SVGA_REG_MEM_REGS);
        min <<= 2;

        if (min < PAGE_SIZE)
                min = PAGE_SIZE;

        iowrite32(min, fifo_mem + SVGA_FIFO_MIN);
        iowrite32(dev_priv->mmio_size, fifo_mem + SVGA_FIFO_MAX);
        wmb();
        iowrite32(min,  fifo_mem + SVGA_FIFO_NEXT_CMD);
        iowrite32(min,  fifo_mem + SVGA_FIFO_STOP);
        iowrite32(0, fifo_mem + SVGA_FIFO_BUSY);
        mb();

        vmw_write(dev_priv, SVGA_REG_CONFIG_DONE, 1);
        mutex_unlock(&dev_priv->hw_mutex);

        max = ioread32(fifo_mem + SVGA_FIFO_MAX);
        min = ioread32(fifo_mem  + SVGA_FIFO_MIN);
        fifo->capabilities = ioread32(fifo_mem + SVGA_FIFO_CAPABILITIES);

        DRM_INFO("Fifo max 0x%08x min 0x%08x cap 0x%08x\n",
                 (unsigned int) max,
                 (unsigned int) min,
                 (unsigned int) fifo->capabilities);

        atomic_set(&dev_priv->marker_seq, dev_priv->last_read_seqno);
        iowrite32(dev_priv->last_read_seqno, fifo_mem + SVGA_FIFO_FENCE);
        vmw_marker_queue_init(&fifo->marker_queue);
        return vmw_fifo_send_fence(dev_priv, &dummy);
}

void vmw_fifo_ping_host(struct vmw_private *dev_priv, uint32_t reason)
{
        __le32 __iomem *fifo_mem = dev_priv->mmio_virt;

        mutex_lock(&dev_priv->hw_mutex);

        if (unlikely(ioread32(fifo_mem + SVGA_FIFO_BUSY) == 0)) {
                iowrite32(1, fifo_mem + SVGA_FIFO_BUSY);
                vmw_write(dev_priv, SVGA_REG_SYNC, reason);
        }

        mutex_unlock(&dev_priv->hw_mutex);
}

void vmw_fifo_release(struct vmw_private *dev_priv, struct vmw_fifo_state *fifo)
{
        __le32 __iomem *fifo_mem = dev_priv->mmio_virt;

        mutex_lock(&dev_priv->hw_mutex);

        while (vmw_read(dev_priv, SVGA_REG_BUSY) != 0)
                vmw_write(dev_priv, SVGA_REG_SYNC, SVGA_SYNC_GENERIC);

        dev_priv->last_read_seqno = ioread32(fifo_mem + SVGA_FIFO_FENCE);

        vmw_write(dev_priv, SVGA_REG_CONFIG_DONE,
                  dev_priv->config_done_state);
        vmw_write(dev_priv, SVGA_REG_ENABLE,
                  dev_priv->enable_state);
        vmw_write(dev_priv, SVGA_REG_TRACES,
                  dev_priv->traces_state);

        mutex_unlock(&dev_priv->hw_mutex);
        vmw_marker_queue_takedown(&fifo->marker_queue);

        if (likely(fifo->static_buffer != NULL)) {
                vfree(fifo->static_buffer);
                fifo->static_buffer = NULL;
        }

        if (likely(fifo->dynamic_buffer != NULL)) {
                vfree(fifo->dynamic_buffer);
                fifo->dynamic_buffer = NULL;
        }
}

static bool vmw_fifo_is_full(struct vmw_private *dev_priv, uint32_t bytes)
{
        __le32 __iomem *fifo_mem = dev_priv->mmio_virt;
        uint32_t max = ioread32(fifo_mem + SVGA_FIFO_MAX);
        uint32_t next_cmd = ioread32(fifo_mem + SVGA_FIFO_NEXT_CMD);
        uint32_t min = ioread32(fifo_mem + SVGA_FIFO_MIN);
        uint32_t stop = ioread32(fifo_mem + SVGA_FIFO_STOP);

        return ((max - next_cmd) + (stop - min) <= bytes);
}

static int vmw_fifo_wait_noirq(struct vmw_private *dev_priv,
                               uint32_t bytes, bool interruptible,
                               unsigned long timeout)
{
        int ret = 0;
        unsigned long end_jiffies = jiffies + timeout;
        DEFINE_WAIT(__wait);

        DRM_INFO("Fifo wait noirq.\n");

        for (;;) {
                prepare_to_wait(&dev_priv->fifo_queue, &__wait,
                                (interruptible) ?
                                TASK_INTERRUPTIBLE : TASK_UNINTERRUPTIBLE);
                if (!vmw_fifo_is_full(dev_priv, bytes))
                        break;
                if (time_after_eq(jiffies, end_jiffies)) {
                        ret = -EBUSY;
                        DRM_ERROR("SVGA device lockup.\n");
                        break;
                }
                schedule_timeout(1);
                if (interruptible && signal_pending(current)) {
                        ret = -ERESTARTSYS;
                        break;
                }
        }
        finish_wait(&dev_priv->fifo_queue, &__wait);
        wake_up_all(&dev_priv->fifo_queue);
        DRM_INFO("Fifo noirq exit.\n");
        return ret;
}

static int vmw_fifo_wait(struct vmw_private *dev_priv,
                         uint32_t bytes, bool interruptible,
                         unsigned long timeout)
{
        long ret = 1L;
        unsigned long irq_flags;

        if (likely(!vmw_fifo_is_full(dev_priv, bytes)))
                return 0;

        vmw_fifo_ping_host(dev_priv, SVGA_SYNC_FIFOFULL);
        if (!(dev_priv->capabilities & SVGA_CAP_IRQMASK))
                return vmw_fifo_wait_noirq(dev_priv, bytes,
                                           interruptible, timeout);

        mutex_lock(&dev_priv->hw_mutex);
        if (atomic_add_return(1, &dev_priv->fifo_queue_waiters) > 0) {
                spin_lock_irqsave(&dev_priv->irq_lock, irq_flags);
                outl(SVGA_IRQFLAG_FIFO_PROGRESS,
                     dev_priv->io_start + VMWGFX_IRQSTATUS_PORT);
                dev_priv->irq_mask |= SVGA_IRQFLAG_FIFO_PROGRESS;
                vmw_write(dev_priv, SVGA_REG_IRQMASK, dev_priv->irq_mask);
                spin_unlock_irqrestore(&dev_priv->irq_lock, irq_flags);
        }
        mutex_unlock(&dev_priv->hw_mutex);

        if (interruptible)
                ret = wait_event_interruptible_timeout
                    (dev_priv->fifo_queue,
                     !vmw_fifo_is_full(dev_priv, bytes), timeout);
        else
                ret = wait_event_timeout
                    (dev_priv->fifo_queue,
                     !vmw_fifo_is_full(dev_priv, bytes), timeout);

        if (unlikely(ret == 0))
                ret = -EBUSY;
        else if (likely(ret > 0))
                ret = 0;

        mutex_lock(&dev_priv->hw_mutex);
        if (atomic_dec_and_test(&dev_priv->fifo_queue_waiters)) {
                spin_lock_irqsave(&dev_priv->irq_lock, irq_flags);
                dev_priv->irq_mask &= ~SVGA_IRQFLAG_FIFO_PROGRESS;
                vmw_write(dev_priv, SVGA_REG_IRQMASK, dev_priv->irq_mask);
                spin_unlock_irqrestore(&dev_priv->irq_lock, irq_flags);
        }
        mutex_unlock(&dev_priv->hw_mutex);

        return ret;
}

/**
 * Reserve @bytes number of bytes in the fifo.
 *
 * This function will return NULL (error) on two conditions:
 *  If it timeouts waiting for fifo space, or if @bytes is larger than the
 *   available fifo space.
 *
 * Returns:
 *   Pointer to the fifo, or null on error (possible hardware hang).
 */
void *vmw_fifo_reserve(struct vmw_private *dev_priv, uint32_t bytes)
{
        struct vmw_fifo_state *fifo_state = &dev_priv->fifo;
        __le32 __iomem *fifo_mem = dev_priv->mmio_virt;
        uint32_t max;
        uint32_t min;
        uint32_t next_cmd;
        uint32_t reserveable = fifo_state->capabilities & SVGA_FIFO_CAP_RESERVE;
        int ret;

        mutex_lock(&fifo_state->fifo_mutex);
        max = ioread32(fifo_mem + SVGA_FIFO_MAX);
        min = ioread32(fifo_mem + SVGA_FIFO_MIN);
        next_cmd = ioread32(fifo_mem + SVGA_FIFO_NEXT_CMD);

        if (unlikely(bytes >= (max - min)))
                goto out_err;

        BUG_ON(fifo_state->reserved_size != 0);
        BUG_ON(fifo_state->dynamic_buffer != NULL);

        fifo_state->reserved_size = bytes;

        while (1) {
                uint32_t stop = ioread32(fifo_mem + SVGA_FIFO_STOP);
                bool need_bounce = false;
                bool reserve_in_place = false;

                if (next_cmd >= stop) {
                        if (likely((next_cmd + bytes < max ||
                                    (next_cmd + bytes == max && stop > min))))
                                reserve_in_place = true;

                        else if (vmw_fifo_is_full(dev_priv, bytes)) {
                                ret = vmw_fifo_wait(dev_priv, bytes,
                                                    false, 3 * HZ);
                                if (unlikely(ret != 0))
                                        goto out_err;
                        } else
                                need_bounce = true;

                } else {

                        if (likely((next_cmd + bytes < stop)))
                                reserve_in_place = true;
                        else {
                                ret = vmw_fifo_wait(dev_priv, bytes,
                                                    false, 3 * HZ);
                                if (unlikely(ret != 0))
                                        goto out_err;
                        }
                }

                if (reserve_in_place) {
                        if (reserveable || bytes <= sizeof(uint32_t)) {
                                fifo_state->using_bounce_buffer = false;

                                if (reserveable)
                                        iowrite32(bytes, fifo_mem +
                                                  SVGA_FIFO_RESERVED);
                                return fifo_mem + (next_cmd >> 2);
                        } else {
                                need_bounce = true;
                        }
                }

                if (need_bounce) {
                        fifo_state->using_bounce_buffer = true;
                        if (bytes < fifo_state->static_buffer_size)
                                return fifo_state->static_buffer;
                        else {
                                fifo_state->dynamic_buffer = vmalloc(bytes);
                                return fifo_state->dynamic_buffer;
                        }
                }
        }
out_err:
        fifo_state->reserved_size = 0;
        mutex_unlock(&fifo_state->fifo_mutex);
        return NULL;
}

static void vmw_fifo_res_copy(struct vmw_fifo_state *fifo_state,
                              __le32 __iomem *fifo_mem,
                              uint32_t next_cmd,
                              uint32_t max, uint32_t min, uint32_t bytes)
{
        uint32_t chunk_size = max - next_cmd;
        uint32_t rest;
        uint32_t *buffer = (fifo_state->dynamic_buffer != NULL) ?
            fifo_state->dynamic_buffer : fifo_state->static_buffer;

        if (bytes < chunk_size)
                chunk_size = bytes;

        iowrite32(bytes, fifo_mem + SVGA_FIFO_RESERVED);
        mb();
        memcpy_toio(fifo_mem + (next_cmd >> 2), buffer, chunk_size);
        rest = bytes - chunk_size;
        if (rest)
                memcpy_toio(fifo_mem + (min >> 2), buffer + (chunk_size >> 2),
                            rest);
}

static void vmw_fifo_slow_copy(struct vmw_fifo_state *fifo_state,
                               __le32 __iomem *fifo_mem,
                               uint32_t next_cmd,
                               uint32_t max, uint32_t min, uint32_t bytes)
{
        uint32_t *buffer = (fifo_state->dynamic_buffer != NULL) ?
            fifo_state->dynamic_buffer : fifo_state->static_buffer;

        while (bytes > 0) {
                iowrite32(*buffer++, fifo_mem + (next_cmd >> 2));
                next_cmd += sizeof(uint32_t);
                if (unlikely(next_cmd == max))
                        next_cmd = min;
                mb();
                iowrite32(next_cmd, fifo_mem + SVGA_FIFO_NEXT_CMD);
                mb();
                bytes -= sizeof(uint32_t);
        }
}

void vmw_fifo_commit(struct vmw_private *dev_priv, uint32_t bytes)
{
        struct vmw_fifo_state *fifo_state = &dev_priv->fifo;
        __le32 __iomem *fifo_mem = dev_priv->mmio_virt;
        uint32_t next_cmd = ioread32(fifo_mem + SVGA_FIFO_NEXT_CMD);
        uint32_t max = ioread32(fifo_mem + SVGA_FIFO_MAX);
        uint32_t min = ioread32(fifo_mem + SVGA_FIFO_MIN);
        bool reserveable = fifo_state->capabilities & SVGA_FIFO_CAP_RESERVE;

        BUG_ON((bytes & 3) != 0);
        BUG_ON(bytes > fifo_state->reserved_size);

        fifo_state->reserved_size = 0;

        if (fifo_state->using_bounce_buffer) {
                if (reserveable)
                        vmw_fifo_res_copy(fifo_state, fifo_mem,
                                          next_cmd, max, min, bytes);
                else
                        vmw_fifo_slow_copy(fifo_state, fifo_mem,
                                           next_cmd, max, min, bytes);

                if (fifo_state->dynamic_buffer) {
                        vfree(fifo_state->dynamic_buffer);
                        fifo_state->dynamic_buffer = NULL;
                }

        }

        down_write(&fifo_state->rwsem);
        if (fifo_state->using_bounce_buffer || reserveable) {
                next_cmd += bytes;
                if (next_cmd >= max)
                        next_cmd -= max - min;
                mb();
                iowrite32(next_cmd, fifo_mem + SVGA_FIFO_NEXT_CMD);
        }

        if (reserveable)
                iowrite32(0, fifo_mem + SVGA_FIFO_RESERVED);
        mb();
        up_write(&fifo_state->rwsem);
        vmw_fifo_ping_host(dev_priv, SVGA_SYNC_GENERIC);
        mutex_unlock(&fifo_state->fifo_mutex);
}

int vmw_fifo_send_fence(struct vmw_private *dev_priv, uint32_t *seqno)
{
        struct vmw_fifo_state *fifo_state = &dev_priv->fifo;
        struct svga_fifo_cmd_fence *cmd_fence;
        void *fm;
        int ret = 0;
        uint32_t bytes = sizeof(__le32) + sizeof(*cmd_fence);

        fm = vmw_fifo_reserve(dev_priv, bytes);
        if (unlikely(fm == NULL)) {
                *seqno = atomic_read(&dev_priv->marker_seq);
                ret = -ENOMEM;
                (void)vmw_fallback_wait(dev_priv, false, true, *seqno,
                                        false, 3*HZ);
                goto out_err;
        }

        do {
                *seqno = atomic_add_return(1, &dev_priv->marker_seq);
        } while (*seqno == 0);

        if (!(fifo_state->capabilities & SVGA_FIFO_CAP_FENCE)) {

                /*
                 * Don't request hardware to send a fence. The
                 * waiting code in vmwgfx_irq.c will emulate this.
                 */

                vmw_fifo_commit(dev_priv, 0);
                return 0;
        }

        *(__le32 *) fm = cpu_to_le32(SVGA_CMD_FENCE);
        cmd_fence = (struct svga_fifo_cmd_fence *)
            ((unsigned long)fm + sizeof(__le32));

        iowrite32(*seqno, &cmd_fence->fence);
        vmw_fifo_commit(dev_priv, bytes);
        (void) vmw_marker_push(&fifo_state->marker_queue, *seqno);
        vmw_update_seqno(dev_priv, fifo_state);

out_err:
        return ret;
}

/**
 * vmw_fifo_emit_dummy_query - emits a dummy query to the fifo.
 *
 * @dev_priv: The device private structure.
 * @cid: The hardware context id used for the query.
 *
 * This function is used to emit a dummy occlusion query with
 * no primitives rendered between query begin and query end.
 * It's used to provide a query barrier, in order to know that when
 * this query is finished, all preceding queries are also finished.
 *
 * A Query results structure should have been initialized at the start
 * of the dev_priv->dummy_query_bo buffer object. And that buffer object
 * must also be either reserved or pinned when this function is called.
 *
 * Returns -ENOMEM on failure to reserve fifo space.
 */
int vmw_fifo_emit_dummy_query(struct vmw_private *dev_priv,
                              uint32_t cid)
{
        /*
         * A query wait without a preceding query end will
         * actually finish all queries for this cid
         * without writing to the query result structure.
         */

        struct ttm_buffer_object *bo = dev_priv->dummy_query_bo;
        struct {
                SVGA3dCmdHeader header;
                SVGA3dCmdWaitForQuery body;
        } *cmd;

        cmd = vmw_fifo_reserve(dev_priv, sizeof(*cmd));

        if (unlikely(cmd == NULL)) {
                DRM_ERROR("Out of fifo space for dummy query.\n");
                return -ENOMEM;
        }

        cmd->header.id = SVGA_3D_CMD_WAIT_FOR_QUERY;
        cmd->header.size = sizeof(cmd->body);
        cmd->body.cid = cid;
        cmd->body.type = SVGA3D_QUERYTYPE_OCCLUSION;

        if (bo->mem.mem_type == TTM_PL_VRAM) {
                cmd->body.guestResult.gmrId = SVGA_GMR_FRAMEBUFFER;
                cmd->body.guestResult.offset = bo->offset;
        } else {
                cmd->body.guestResult.gmrId = bo->mem.start;
                cmd->body.guestResult.offset = 0;
        }

        vmw_fifo_commit(dev_priv, sizeof(*cmd));

        return 0;
}