drivers/gpu/drm/vmwgfx/vmwgfx_fence.c

   1 /**************************************************************************
   2  *
   3  * Copyright (C) 2010 VMware, Inc., Palo Alto, CA., USA
   4  * All Rights Reserved.
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a
   7  * copy of this software and associated documentation files (the
   8  * "Software"), to deal in the Software without restriction, including
   9  * without limitation the rights to use, copy, modify, merge, publish,
  10  * distribute, sub license, and/or sell copies of the Software, and to
  11  * permit persons to whom the Software is furnished to do so, subject to
  12  * the following conditions:
  13  *
  14  * The above copyright notice and this permission notice (including the
  15  * next paragraph) shall be included in all copies or substantial portions
  16  * of the Software.
  17  *
  18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  19  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  20  * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
  21  * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
  22  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
  23  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
  24  * USE OR OTHER DEALINGS IN THE SOFTWARE.
  25  *
  26  **************************************************************************/
  27
  28
  29 #include "vmwgfx_drv.h"
  30
  31 struct vmw_fence {
  32         struct list_head head;
  33         uint32_t sequence;
  34         struct timespec submitted;
  35 };
  36
  37 void vmw_fence_queue_init(struct vmw_fence_queue *queue)
  38 {
  39         INIT_LIST_HEAD(&queue->head);
  40         queue->lag = ns_to_timespec(0);
  41         getrawmonotonic(&queue->lag_time);
  42         spin_lock_init(&queue->lock);
  43 }
  44
  45 void vmw_fence_queue_takedown(struct vmw_fence_queue *queue)
  46 {
  47         struct vmw_fence *fence, *next;
  48
  49         spin_lock(&queue->lock);
  50         list_for_each_entry_safe(fence, next, &queue->head, head) {
  51                 kfree(fence);
  52         }
  53         spin_unlock(&queue->lock);
  54 }
  55
  56 int vmw_fence_push(struct vmw_fence_queue *queue,
  57                    uint32_t sequence)
  58 {
  59         struct vmw_fence *fence = kmalloc(sizeof(*fence), GFP_KERNEL);
  60
  61         if (unlikely(!fence))
  62                 return -ENOMEM;
  63
  64         fence->sequence = sequence;
  65         getrawmonotonic(&fence->submitted);
  66         spin_lock(&queue->lock);
  67         list_add_tail(&fence->head, &queue->head);
  68         spin_unlock(&queue->lock);
  69
  70         return 0;
  71 }
  72
  73 int vmw_fence_pull(struct vmw_fence_queue *queue,
  74                    uint32_t signaled_sequence)
  75 {
  76         struct vmw_fence *fence, *next;
  77         struct timespec now;
  78         bool updated = false;
  79
  80         spin_lock(&queue->lock);
  81         getrawmonotonic(&now);
  82
  83         if (list_empty(&queue->head)) {
  84                 queue->lag = ns_to_timespec(0);
  85                 queue->lag_time = now;
  86                 updated = true;
  87                 goto out_unlock;
  88         }
  89
  90         list_for_each_entry_safe(fence, next, &queue->head, head) {
  91                 if (signaled_sequence - fence->sequence > (1 << 30))
  92                         continue;
  93
  94                 queue->lag = timespec_sub(now, fence->submitted);
  95                 queue->lag_time = now;
  96                 updated = true;
  97                 list_del(&fence->head);
  98                 kfree(fence);
  99         }
 100
 101 out_unlock:
 102         spin_unlock(&queue->lock);
 103
 104         return (updated) ? 0 : -EBUSY;
 105 }
 106
 107 static struct timespec vmw_timespec_add(struct timespec t1,
 108                                         struct timespec t2)
 109 {
 110         t1.tv_sec += t2.tv_sec;
 111         t1.tv_nsec += t2.tv_nsec;
 112         if (t1.tv_nsec >= 1000000000L) {
 113                 t1.tv_sec += 1;
 114                 t1.tv_nsec -= 1000000000L;
 115         }
 116
 117         return t1;
 118 }
 119
 120 static struct timespec vmw_fifo_lag(struct vmw_fence_queue *queue)
 121 {
 122         struct timespec now;
 123
 124         spin_lock(&queue->lock);
 125         getrawmonotonic(&now);
 126         queue->lag = vmw_timespec_add(queue->lag,
 127                                       timespec_sub(now, queue->lag_time));
 128         queue->lag_time = now;
 129         spin_unlock(&queue->lock);
 130         return queue->lag;
 131 }
 132
 133
 134 static bool vmw_lag_lt(struct vmw_fence_queue *queue,
 135                        uint32_t us)
 136 {
 137         struct timespec lag, cond;
 138
 139         cond = ns_to_timespec((s64) us * 1000);
 140         lag = vmw_fifo_lag(queue);
 141         return (timespec_compare(&lag, &cond) < 1);
 142 }
 143
 144 int vmw_wait_lag(struct vmw_private *dev_priv,
 145                  struct vmw_fence_queue *queue, uint32_t us)
 146 {
 147         struct vmw_fence *fence;
 148         uint32_t sequence;
 149         int ret;
 150
 151         while (!vmw_lag_lt(queue, us)) {
 152                 spin_lock(&queue->lock);
 153                 if (list_empty(&queue->head))
 154                         sequence = atomic_read(&dev_priv->fence_seq);
 155                 else {
 156                         fence = list_first_entry(&queue->head,
 157                                                  struct vmw_fence, head);
 158                         sequence = fence->sequence;
 159                 }
 160                 spin_unlock(&queue->lock);
 161
 162                 ret = vmw_wait_fence(dev_priv, false, sequence, true,
 163                                      3*HZ);
 164
 165                 if (unlikely(ret != 0))
 166                         return ret;
 167
 168                 (void) vmw_fence_pull(queue, sequence);
 169         }
 170         return 0;
 171 }
 172
 173