drivers/gpu/drm/nouveau/nouveau_fence.c

   1 /*
   2  * Copyright (C) 2007 Ben Skeggs.
   3  * All Rights Reserved.
   4  *
   5  * Permission is hereby granted, free of charge, to any person obtaining
   6  * a copy of this software and associated documentation files (the
   7  * "Software"), to deal in the Software without restriction, including
   8  * without limitation the rights to use, copy, modify, merge, publish,
   9  * distribute, sublicense, and/or sell copies of the Software, and to
  10  * permit persons to whom the Software is furnished to do so, subject to
  11  * the following conditions:
  12  *
  13  * The above copyright notice and this permission notice (including the
  14  * next paragraph) shall be included in all copies or substantial
  15  * portions of the Software.
  16  *
  17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  18  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  19  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
  20  * IN NO EVENT SHALL THE COPYRIGHT OWNER(S) AND/OR ITS SUPPLIERS BE
  21  * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  22  * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  23  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  24  *
  25  */
  26
  27 #include <drm/drmP.h>
  28
  29 #include <linux/ktime.h>
  30 #include <linux/hrtimer.h>
  31 #include <trace/events/fence.h>
  32
  33 #include <nvif/notify.h>
  34 #include <nvif/event.h>
  35
  36 #include "nouveau_drm.h"
  37 #include "nouveau_dma.h"
  38 #include "nouveau_fence.h"
  39
  40 static const struct fence_ops nouveau_fence_ops_uevent;
  41 static const struct fence_ops nouveau_fence_ops_legacy;
  42
  43 static inline struct nouveau_fence *
  44 from_fence(struct fence *fence)
  45 {
  46         return container_of(fence, struct nouveau_fence, base);
  47 }
  48
  49 static inline struct nouveau_fence_chan *
  50 nouveau_fctx(struct nouveau_fence *fence)
  51 {
  52         return container_of(fence->base.lock, struct nouveau_fence_chan, lock);
  53 }
  54
  55 static void
  56 nouveau_fence_signal(struct nouveau_fence *fence)
  57 {
  58         fence_signal_locked(&fence->base);
  59         list_del(&fence->head);
  60
  61         if (test_bit(FENCE_FLAG_USER_BITS, &fence->base.flags)) {
  62                 struct nouveau_fence_chan *fctx = nouveau_fctx(fence);
  63
  64                 if (!--fctx->notify_ref)
  65                         nvif_notify_put(&fctx->notify);
  66         }
  67
  68         fence_put(&fence->base);
  69 }
  70
  71 static struct nouveau_fence *
  72 nouveau_local_fence(struct fence *fence, struct nouveau_drm *drm) {
  73         struct nouveau_fence_priv *priv = (void*)drm->fence;
  74
  75         if (fence->ops != &nouveau_fence_ops_legacy &&
  76             fence->ops != &nouveau_fence_ops_uevent)
  77                 return NULL;
  78
  79         if (fence->context < priv->context_base ||
  80             fence->context >= priv->context_base + priv->contexts)
  81                 return NULL;
  82
  83         return from_fence(fence);
  84 }
  85
  86 void
  87 nouveau_fence_context_del(struct nouveau_fence_chan *fctx)
  88 {
  89         struct nouveau_fence *fence;
  90
  91         nvif_notify_fini(&fctx->notify);
  92
  93         spin_lock_irq(&fctx->lock);
  94         while (!list_empty(&fctx->pending)) {
  95                 fence = list_entry(fctx->pending.next, typeof(*fence), head);
  96
  97                 nouveau_fence_signal(fence);
  98                 fence->channel = NULL;
  99         }
 100         spin_unlock_irq(&fctx->lock);
 101 }
 102
 103 static void
 104 nouveau_fence_context_put(struct kref *fence_ref)
 105 {
 106         kfree(container_of(fence_ref, struct nouveau_fence_chan, fence_ref));
 107 }
 108
 109 void
 110 nouveau_fence_context_free(struct nouveau_fence_chan *fctx)
 111 {
 112         kref_put(&fctx->fence_ref, nouveau_fence_context_put);
 113 }
 114
 115 static void
 116 nouveau_fence_update(struct nouveau_channel *chan, struct nouveau_fence_chan *fctx)
 117 {
 118         struct nouveau_fence *fence;
 119
 120         u32 seq = fctx->read(chan);
 121
 122         while (!list_empty(&fctx->pending)) {
 123                 fence = list_entry(fctx->pending.next, typeof(*fence), head);
 124
 125                 if ((int)(seq - fence->base.seqno) < 0)
 126                         return;
 127
 128                 nouveau_fence_signal(fence);
 129         }
 130 }
 131
 132 static int
 133 nouveau_fence_wait_uevent_handler(struct nvif_notify *notify)
 134 {
 135         struct nouveau_fence_chan *fctx =
 136                 container_of(notify, typeof(*fctx), notify);
 137         unsigned long flags;
 138
 139         spin_lock_irqsave(&fctx->lock, flags);
 140         if (!list_empty(&fctx->pending)) {
 141                 struct nouveau_fence *fence;
 142
 143                 fence = list_entry(fctx->pending.next, typeof(*fence), head);
 144                 nouveau_fence_update(fence->channel, fctx);
 145         }
 146         spin_unlock_irqrestore(&fctx->lock, flags);
 147
 148         /* Always return keep here. NVIF refcount is handled with nouveau_fence_update */
 149         return NVIF_NOTIFY_KEEP;
 150 }
 151
 152 void
 153 nouveau_fence_context_new(struct nouveau_channel *chan, struct nouveau_fence_chan *fctx)
 154 {
 155         struct nouveau_fence_priv *priv = (void*)chan->drm->fence;
 156         struct nouveau_cli *cli = (void *)nvif_client(chan->object);
 157         int ret;
 158
 159         INIT_LIST_HEAD(&fctx->flip);
 160         INIT_LIST_HEAD(&fctx->pending);
 161         spin_lock_init(&fctx->lock);
 162         fctx->context = priv->context_base + chan->chid;
 163
 164         if (chan == chan->drm->cechan)
 165                 strcpy(fctx->name, "copy engine channel");
 166         else if (chan == chan->drm->channel)
 167                 strcpy(fctx->name, "generic kernel channel");
 168         else
 169                 strcpy(fctx->name, nvkm_client(&cli->base)->name);
 170
 171         kref_init(&fctx->fence_ref);
 172         if (!priv->uevent)
 173                 return;
 174
 175         ret = nvif_notify_init(chan->object, NULL,
 176                          nouveau_fence_wait_uevent_handler, false,
 177                          G82_CHANNEL_DMA_V0_NTFY_UEVENT,
 178                          &(struct nvif_notify_uevent_req) { },
 179                          sizeof(struct nvif_notify_uevent_req),
 180                          sizeof(struct nvif_notify_uevent_rep),
 181                          &fctx->notify);
 182
 183         WARN_ON(ret);
 184 }
 185
 186 struct nouveau_fence_work {
 187         struct work_struct work;
 188         struct fence_cb cb;
 189         void (*func)(void *);
 190         void *data;
 191 };
 192
 193 static void
 194 nouveau_fence_work_handler(struct work_struct *kwork)
 195 {
 196         struct nouveau_fence_work *work = container_of(kwork, typeof(*work), work);
 197         work->func(work->data);
 198         kfree(work);
 199 }
 200
 201 static void nouveau_fence_work_cb(struct fence *fence, struct fence_cb *cb)
 202 {
 203         struct nouveau_fence_work *work = container_of(cb, typeof(*work), cb);
 204
 205         schedule_work(&work->work);
 206 }
 207
 208 void
 209 nouveau_fence_work(struct fence *fence,
 210                    void (*func)(void *), void *data)
 211 {
 212         struct nouveau_fence_work *work;
 213
 214         if (fence_is_signaled(fence))
 215                 goto err;
 216
 217         work = kmalloc(sizeof(*work), GFP_KERNEL);
 218         if (!work) {
 219                 /*
 220                  * this might not be a nouveau fence any more,
 221                  * so force a lazy wait here
 222                  */
 223                 WARN_ON(nouveau_fence_wait((struct nouveau_fence *)fence,
 224                                            true, false));
 225                 goto err;
 226         }
 227
 228         INIT_WORK(&work->work, nouveau_fence_work_handler);
 229         work->func = func;
 230         work->data = data;
 231
 232         if (fence_add_callback(fence, &work->cb, nouveau_fence_work_cb) < 0)
 233                 goto err_free;
 234         return;
 235
 236 err_free:
 237         kfree(work);
 238 err:
 239         func(data);
 240 }
 241
 242 int
 243 nouveau_fence_emit(struct nouveau_fence *fence, struct nouveau_channel *chan)
 244 {
 245         struct nouveau_fence_chan *fctx = chan->fence;
 246         struct nouveau_fence_priv *priv = (void*)chan->drm->fence;
 247         int ret;
 248
 249         fence->channel  = chan;
 250         fence->timeout  = jiffies + (15 * HZ);
 251
 252         if (priv->uevent)
 253                 fence_init(&fence->base, &nouveau_fence_ops_uevent,
 254                            &fctx->lock, fctx->context, ++fctx->sequence);
 255         else
 256                 fence_init(&fence->base, &nouveau_fence_ops_legacy,
 257                            &fctx->lock, fctx->context, ++fctx->sequence);
 258         kref_get(&fctx->fence_ref);
 259
 260         trace_fence_emit(&fence->base);
 261         ret = fctx->emit(fence);
 262         if (!ret) {
 263                 fence_get(&fence->base);
 264                 spin_lock_irq(&fctx->lock);
 265                 nouveau_fence_update(chan, fctx);
 266                 list_add_tail(&fence->head, &fctx->pending);
 267                 spin_unlock_irq(&fctx->lock);
 268         }
 269
 270         return ret;
 271 }
 272
 273 bool
 274 nouveau_fence_done(struct nouveau_fence *fence)
 275 {
 276         if (fence->base.ops == &nouveau_fence_ops_legacy ||
 277             fence->base.ops == &nouveau_fence_ops_uevent) {
 278                 struct nouveau_fence_chan *fctx = nouveau_fctx(fence);
 279                 unsigned long flags;
 280
 281                 if (test_bit(FENCE_FLAG_SIGNALED_BIT, &fence->base.flags))
 282                         return true;
 283
 284                 spin_lock_irqsave(&fctx->lock, flags);
 285                 nouveau_fence_update(fence->channel, fctx);
 286                 spin_unlock_irqrestore(&fctx->lock, flags);
 287         }
 288         return fence_is_signaled(&fence->base);
 289 }
 290
 291 static long
 292 nouveau_fence_wait_legacy(struct fence *f, bool intr, long wait)
 293 {
 294         struct nouveau_fence *fence = from_fence(f);
 295         unsigned long sleep_time = NSEC_PER_MSEC / 1000;
 296         unsigned long t = jiffies, timeout = t + wait;
 297
 298         while (!nouveau_fence_done(fence)) {
 299                 ktime_t kt;
 300
 301                 t = jiffies;
 302
 303                 if (wait != MAX_SCHEDULE_TIMEOUT && time_after_eq(t, timeout)) {
 304                         __set_current_state(TASK_RUNNING);
 305                         return 0;
 306                 }
 307
 308                 __set_current_state(intr ? TASK_INTERRUPTIBLE :
 309                                            TASK_UNINTERRUPTIBLE);
 310
 311                 kt = ktime_set(0, sleep_time);
 312                 schedule_hrtimeout(&kt, HRTIMER_MODE_REL);
 313                 sleep_time *= 2;
 314                 if (sleep_time > NSEC_PER_MSEC)
 315                         sleep_time = NSEC_PER_MSEC;
 316
 317                 if (intr && signal_pending(current))
 318                         return -ERESTARTSYS;
 319         }
 320
 321         __set_current_state(TASK_RUNNING);
 322
 323         return timeout - t;
 324 }
 325
 326 static int
 327 nouveau_fence_wait_busy(struct nouveau_fence *fence, bool intr)
 328 {
 329         int ret = 0;
 330
 331         while (!nouveau_fence_done(fence)) {
 332                 if (time_after_eq(jiffies, fence->timeout)) {
 333                         ret = -EBUSY;
 334                         break;
 335                 }
 336
 337                 __set_current_state(intr ?
 338                                     TASK_INTERRUPTIBLE :
 339                                     TASK_UNINTERRUPTIBLE);
 340
 341                 if (intr && signal_pending(current)) {
 342                         ret = -ERESTARTSYS;
 343                         break;
 344                 }
 345         }
 346
 347         __set_current_state(TASK_RUNNING);
 348         return ret;
 349 }
 350
 351 int
 352 nouveau_fence_wait(struct nouveau_fence *fence, bool lazy, bool intr)
 353 {
 354         long ret;
 355
 356         if (!lazy)
 357                 return nouveau_fence_wait_busy(fence, intr);
 358
 359         ret = fence_wait_timeout(&fence->base, intr, 15 * HZ);
 360         if (ret < 0)
 361                 return ret;
 362         else if (!ret)
 363                 return -EBUSY;
 364         else
 365                 return 0;
 366 }
 367
 368 int
 369 nouveau_fence_sync(struct nouveau_bo *nvbo, struct nouveau_channel *chan, bool exclusive, bool intr)
 370 {
 371         struct nouveau_fence_chan *fctx = chan->fence;
 372         struct fence *fence;
 373         struct reservation_object *resv = nvbo->bo.resv;
 374         struct reservation_object_list *fobj;
 375         struct nouveau_fence *f;
 376         int ret = 0, i;
 377
 378         if (!exclusive) {
 379                 ret = reservation_object_reserve_shared(resv);
 380
 381                 if (ret)
 382                         return ret;
 383         }
 384
 385         fobj = reservation_object_get_list(resv);
 386         fence = reservation_object_get_excl(resv);
 387
 388         if (fence && (!exclusive || !fobj || !fobj->shared_count)) {
 389                 struct nouveau_channel *prev = NULL;
 390
 391                 f = nouveau_local_fence(fence, chan->drm);
 392                 if (f)
 393                         prev = f->channel;
 394
 395                 if (!prev || (prev != chan && (ret = fctx->sync(f, prev, chan))))
 396                         ret = fence_wait(fence, intr);
 397
 398                 return ret;
 399         }
 400
 401         if (!exclusive || !fobj)
 402                 return ret;
 403
 404         for (i = 0; i < fobj->shared_count && !ret; ++i) {
 405                 struct nouveau_channel *prev = NULL;
 406
 407                 fence = rcu_dereference_protected(fobj->shared[i],
 408                                                 reservation_object_held(resv));
 409
 410                 f = nouveau_local_fence(fence, chan->drm);
 411                 if (f)
 412                         prev = f->channel;
 413
 414                 if (!prev || (prev != chan && (ret = fctx->sync(f, prev, chan))))
 415                         ret = fence_wait(fence, intr);
 416
 417                 if (ret)
 418                         break;
 419         }
 420
 421         return ret;
 422 }
 423
 424 void
 425 nouveau_fence_unref(struct nouveau_fence **pfence)
 426 {
 427         if (*pfence)
 428                 fence_put(&(*pfence)->base);
 429         *pfence = NULL;
 430 }
 431
 432 int
 433 nouveau_fence_new(struct nouveau_channel *chan, bool sysmem,
 434                   struct nouveau_fence **pfence)
 435 {
 436         struct nouveau_fence *fence;
 437         int ret = 0;
 438
 439         if (unlikely(!chan->fence))
 440                 return -ENODEV;
 441
 442         fence = kzalloc(sizeof(*fence), GFP_KERNEL);
 443         if (!fence)
 444                 return -ENOMEM;
 445
 446         fence->sysmem = sysmem;
 447
 448         ret = nouveau_fence_emit(fence, chan);
 449         if (ret)
 450                 nouveau_fence_unref(&fence);
 451
 452         *pfence = fence;
 453         return ret;
 454 }
 455
 456 static const char *nouveau_fence_get_get_driver_name(struct fence *fence)
 457 {
 458         return "nouveau";
 459 }
 460
 461 static const char *nouveau_fence_get_timeline_name(struct fence *f)
 462 {
 463         struct nouveau_fence *fence = from_fence(f);
 464         struct nouveau_fence_chan *fctx = nouveau_fctx(fence);
 465
 466         return fence->channel ? fctx->name : "dead channel";
 467 }
 468
 469 /*
 470  * In an ideal world, read would not assume the channel context is still alive.
 471  * This function may be called from another device, running into free memory as a
 472  * result. The drm node should still be there, so we can derive the index from
 473  * the fence context.
 474  */
 475 static bool nouveau_fence_is_signaled(struct fence *f)
 476 {
 477         struct nouveau_fence *fence = from_fence(f);
 478         struct nouveau_fence_chan *fctx = nouveau_fctx(fence);
 479         struct nouveau_channel *chan = fence->channel;
 480
 481         return (int)(fctx->read(chan) - fence->base.seqno) >= 0;
 482 }
 483
 484 static bool nouveau_fence_no_signaling(struct fence *f)
 485 {
 486         struct nouveau_fence *fence = from_fence(f);
 487
 488         /*
 489          * caller should have a reference on the fence,
 490          * else fence could get freed here
 491          */
 492         WARN_ON(atomic_read(&fence->base.refcount.refcount) <= 1);
 493
 494         /*
 495          * This needs uevents to work correctly, but fence_add_callback relies on
 496          * being able to enable signaling. It will still get signaled eventually,
 497          * just not right away.
 498          */
 499         if (nouveau_fence_is_signaled(f)) {
 500                 list_del(&fence->head);
 501
 502                 fence_put(&fence->base);
 503                 return false;
 504         }
 505
 506         return true;
 507 }
 508
 509 static void nouveau_fence_release(struct fence *f)
 510 {
 511         struct nouveau_fence *fence = from_fence(f);
 512         struct nouveau_fence_chan *fctx = nouveau_fctx(fence);
 513
 514         kref_put(&fctx->fence_ref, nouveau_fence_context_put);
 515         fence_free(&fence->base);
 516 }
 517
 518 static const struct fence_ops nouveau_fence_ops_legacy = {
 519         .get_driver_name = nouveau_fence_get_get_driver_name,
 520         .get_timeline_name = nouveau_fence_get_timeline_name,
 521         .enable_signaling = nouveau_fence_no_signaling,
 522         .signaled = nouveau_fence_is_signaled,
 523         .wait = nouveau_fence_wait_legacy,
 524         .release = nouveau_fence_release
 525 };
 526
 527 static bool nouveau_fence_enable_signaling(struct fence *f)
 528 {
 529         struct nouveau_fence *fence = from_fence(f);
 530         struct nouveau_fence_chan *fctx = nouveau_fctx(fence);
 531         bool ret;
 532
 533         if (!fctx->notify_ref++)
 534                 nvif_notify_get(&fctx->notify);
 535
 536         ret = nouveau_fence_no_signaling(f);
 537         if (ret)
 538                 set_bit(FENCE_FLAG_USER_BITS, &fence->base.flags);
 539         else if (!--fctx->notify_ref)
 540                 nvif_notify_put(&fctx->notify);
 541
 542         return ret;
 543 }
 544
 545 static const struct fence_ops nouveau_fence_ops_uevent = {
 546         .get_driver_name = nouveau_fence_get_get_driver_name,
 547         .get_timeline_name = nouveau_fence_get_timeline_name,
 548         .enable_signaling = nouveau_fence_enable_signaling,
 549         .signaled = nouveau_fence_is_signaled,
 550         .wait = fence_default_wait,
 551         .release = NULL
 552 };