drivers/gpu/drm/radeon/radeon_ring.c

   1 /*
   2  * Copyright 2008 Advanced Micro Devices, Inc.
   3  * Copyright 2008 Red Hat Inc.
   4  * Copyright 2009 Jerome Glisse.
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a
   7  * copy of this software and associated documentation files (the "Software"),
   8  * to deal in the Software without restriction, including without limitation
   9  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  10  * and/or sell copies of the Software, and to permit persons to whom the
  11  * Software is furnished to do so, subject to the following conditions:
  12  *
  13  * The above copyright notice and this permission notice shall be included in
  14  * all copies or substantial portions of the Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  19  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
  20  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  21  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  22  * OTHER DEALINGS IN THE SOFTWARE.
  23  *
  24  * Authors: Dave Airlie
  25  *          Alex Deucher
  26  *          Jerome Glisse
  27  *          Christian König
  28  */
  29 #include <drm/drmP.h>
  30 #include "radeon.h"
  31
  32 /*
  33  * Rings
  34  * Most engines on the GPU are fed via ring buffers.  Ring
  35  * buffers are areas of GPU accessible memory that the host
  36  * writes commands into and the GPU reads commands out of.
  37  * There is a rptr (read pointer) that determines where the
  38  * GPU is currently reading, and a wptr (write pointer)
  39  * which determines where the host has written.  When the
  40  * pointers are equal, the ring is idle.  When the host
  41  * writes commands to the ring buffer, it increments the
  42  * wptr.  The GPU then starts fetching commands and executes
  43  * them until the pointers are equal again.
  44  */
  45 static int radeon_debugfs_ring_init(struct radeon_device *rdev, struct radeon_ring *ring);
  46
  47 /**
  48  * radeon_ring_supports_scratch_reg - check if the ring supports
  49  * writing to scratch registers
  50  *
  51  * @rdev: radeon_device pointer
  52  * @ring: radeon_ring structure holding ring information
  53  *
  54  * Check if a specific ring supports writing to scratch registers (all asics).
  55  * Returns true if the ring supports writing to scratch regs, false if not.
  56  */
  57 bool radeon_ring_supports_scratch_reg(struct radeon_device *rdev,
  58                                       struct radeon_ring *ring)
  59 {
  60         switch (ring->idx) {
  61         case RADEON_RING_TYPE_GFX_INDEX:
  62         case CAYMAN_RING_TYPE_CP1_INDEX:
  63         case CAYMAN_RING_TYPE_CP2_INDEX:
  64                 return true;
  65         default:
  66                 return false;
  67         }
  68 }
  69
  70 /**
  71  * radeon_ring_free_size - update the free size
  72  *
  73  * @rdev: radeon_device pointer
  74  * @ring: radeon_ring structure holding ring information
  75  *
  76  * Update the free dw slots in the ring buffer (all asics).
  77  */
  78 void radeon_ring_free_size(struct radeon_device *rdev, struct radeon_ring *ring)
  79 {
  80         uint32_t rptr = radeon_ring_get_rptr(rdev, ring);
  81
  82         /* This works because ring_size is a power of 2 */
  83         ring->ring_free_dw = rptr + (ring->ring_size / 4);
  84         ring->ring_free_dw -= ring->wptr;
  85         ring->ring_free_dw &= ring->ptr_mask;
  86         if (!ring->ring_free_dw) {
  87                 /* this is an empty ring */
  88                 ring->ring_free_dw = ring->ring_size / 4;
  89                 /*  update lockup info to avoid false positive */
  90                 radeon_ring_lockup_update(rdev, ring);
  91         }
  92 }
  93
  94 /**
  95  * radeon_ring_alloc - allocate space on the ring buffer
  96  *
  97  * @rdev: radeon_device pointer
  98  * @ring: radeon_ring structure holding ring information
  99  * @ndw: number of dwords to allocate in the ring buffer
 100  *
 101  * Allocate @ndw dwords in the ring buffer (all asics).
 102  * Returns 0 on success, error on failure.
 103  */
 104 int radeon_ring_alloc(struct radeon_device *rdev, struct radeon_ring *ring, unsigned ndw)
 105 {
 106         int r;
 107
 108         /* make sure we aren't trying to allocate more space than there is on the ring */
 109         if (ndw > (ring->ring_size / 4))
 110                 return -ENOMEM;
 111         /* Align requested size with padding so unlock_commit can
 112          * pad safely */
 113         radeon_ring_free_size(rdev, ring);
 114         ndw = (ndw + ring->align_mask) & ~ring->align_mask;
 115         while (ndw > (ring->ring_free_dw - 1)) {
 116                 radeon_ring_free_size(rdev, ring);
 117                 if (ndw < ring->ring_free_dw) {
 118                         break;
 119                 }
 120                 r = radeon_fence_wait_next(rdev, ring->idx);
 121                 if (r)
 122                         return r;
 123         }
 124         ring->count_dw = ndw;
 125         ring->wptr_old = ring->wptr;
 126         return 0;
 127 }
 128
 129 /**
 130  * radeon_ring_lock - lock the ring and allocate space on it
 131  *
 132  * @rdev: radeon_device pointer
 133  * @ring: radeon_ring structure holding ring information
 134  * @ndw: number of dwords to allocate in the ring buffer
 135  *
 136  * Lock the ring and allocate @ndw dwords in the ring buffer
 137  * (all asics).
 138  * Returns 0 on success, error on failure.
 139  */
 140 int radeon_ring_lock(struct radeon_device *rdev, struct radeon_ring *ring, unsigned ndw)
 141 {
 142         int r;
 143
 144         mutex_lock(&rdev->ring_lock);
 145         r = radeon_ring_alloc(rdev, ring, ndw);
 146         if (r) {
 147                 mutex_unlock(&rdev->ring_lock);
 148                 return r;
 149         }
 150         return 0;
 151 }
 152
 153 /**
 154  * radeon_ring_commit - tell the GPU to execute the new
 155  * commands on the ring buffer
 156  *
 157  * @rdev: radeon_device pointer
 158  * @ring: radeon_ring structure holding ring information
 159  * @hdp_flush: Whether or not to perform an HDP cache flush
 160  *
 161  * Update the wptr (write pointer) to tell the GPU to
 162  * execute new commands on the ring buffer (all asics).
 163  */
 164 void radeon_ring_commit(struct radeon_device *rdev, struct radeon_ring *ring,
 165                         bool hdp_flush)
 166 {
 167         /* If we are emitting the HDP flush via the ring buffer, we need to
 168          * do it before padding.
 169          */
 170         if (hdp_flush && rdev->asic->ring[ring->idx]->hdp_flush)
 171                 rdev->asic->ring[ring->idx]->hdp_flush(rdev, ring);
 172         /* We pad to match fetch size */
 173         while (ring->wptr & ring->align_mask) {
 174                 radeon_ring_write(ring, ring->nop);
 175         }
 176         mb();
 177         /* If we are emitting the HDP flush via MMIO, we need to do it after
 178          * all CPU writes to VRAM finished.
 179          */
 180         if (hdp_flush && rdev->asic->mmio_hdp_flush)
 181                 rdev->asic->mmio_hdp_flush(rdev);
 182         radeon_ring_set_wptr(rdev, ring);
 183 }
 184
 185 /**
 186  * radeon_ring_unlock_commit - tell the GPU to execute the new
 187  * commands on the ring buffer and unlock it
 188  *
 189  * @rdev: radeon_device pointer
 190  * @ring: radeon_ring structure holding ring information
 191  * @hdp_flush: Whether or not to perform an HDP cache flush
 192  *
 193  * Call radeon_ring_commit() then unlock the ring (all asics).
 194  */
 195 void radeon_ring_unlock_commit(struct radeon_device *rdev, struct radeon_ring *ring,
 196                                bool hdp_flush)
 197 {
 198         radeon_ring_commit(rdev, ring, hdp_flush);
 199         mutex_unlock(&rdev->ring_lock);
 200 }
 201
 202 /**
 203  * radeon_ring_undo - reset the wptr
 204  *
 205  * @ring: radeon_ring structure holding ring information
 206  *
 207  * Reset the driver's copy of the wptr (all asics).
 208  */
 209 void radeon_ring_undo(struct radeon_ring *ring)
 210 {
 211         ring->wptr = ring->wptr_old;
 212 }
 213
 214 /**
 215  * radeon_ring_unlock_undo - reset the wptr and unlock the ring
 216  *
 217  * @ring: radeon_ring structure holding ring information
 218  *
 219  * Call radeon_ring_undo() then unlock the ring (all asics).
 220  */
 221 void radeon_ring_unlock_undo(struct radeon_device *rdev, struct radeon_ring *ring)
 222 {
 223         radeon_ring_undo(ring);
 224         mutex_unlock(&rdev->ring_lock);
 225 }
 226
 227 /**
 228  * radeon_ring_lockup_update - update lockup variables
 229  *
 230  * @ring: radeon_ring structure holding ring information
 231  *
 232  * Update the last rptr value and timestamp (all asics).
 233  */
 234 void radeon_ring_lockup_update(struct radeon_device *rdev,
 235                                struct radeon_ring *ring)
 236 {
 237         atomic_set(&ring->last_rptr, radeon_ring_get_rptr(rdev, ring));
 238         atomic64_set(&ring->last_activity, jiffies_64);
 239 }
 240
 241 /**
 242  * radeon_ring_test_lockup() - check if ring is lockedup by recording information
 243  * @rdev:       radeon device structure
 244  * @ring:       radeon_ring structure holding ring information
 245  *
 246  */
 247 bool radeon_ring_test_lockup(struct radeon_device *rdev, struct radeon_ring *ring)
 248 {
 249         uint32_t rptr = radeon_ring_get_rptr(rdev, ring);
 250         uint64_t last = atomic64_read(&ring->last_activity);
 251         uint64_t elapsed;
 252
 253         if (rptr != atomic_read(&ring->last_rptr)) {
 254                 /* ring is still working, no lockup */
 255                 radeon_ring_lockup_update(rdev, ring);
 256                 return false;
 257         }
 258
 259         elapsed = jiffies_to_msecs(jiffies_64 - last);
 260         if (radeon_lockup_timeout && elapsed >= radeon_lockup_timeout) {
 261                 dev_err(rdev->dev, "ring %d stalled for more than %llumsec\n",
 262                         ring->idx, elapsed);
 263                 return true;
 264         }
 265         /* give a chance to the GPU ... */
 266         return false;
 267 }
 268
 269 /**
 270  * radeon_ring_backup - Back up the content of a ring
 271  *
 272  * @rdev: radeon_device pointer
 273  * @ring: the ring we want to back up
 274  *
 275  * Saves all unprocessed commits from a ring, returns the number of dwords saved.
 276  */
 277 unsigned radeon_ring_backup(struct radeon_device *rdev, struct radeon_ring *ring,
 278                             uint32_t **data)
 279 {
 280         unsigned size, ptr, i;
 281
 282         /* just in case lock the ring */
 283         mutex_lock(&rdev->ring_lock);
 284         *data = NULL;
 285
 286         if (ring->ring_obj == NULL) {
 287                 mutex_unlock(&rdev->ring_lock);
 288                 return 0;
 289         }
 290
 291         /* it doesn't make sense to save anything if all fences are signaled */
 292         if (!radeon_fence_count_emitted(rdev, ring->idx)) {
 293                 mutex_unlock(&rdev->ring_lock);
 294                 return 0;
 295         }
 296
 297         /* calculate the number of dw on the ring */
 298         if (ring->rptr_save_reg)
 299                 ptr = RREG32(ring->rptr_save_reg);
 300         else if (rdev->wb.enabled)
 301                 ptr = le32_to_cpu(*ring->next_rptr_cpu_addr);
 302         else {
 303                 /* no way to read back the next rptr */
 304                 mutex_unlock(&rdev->ring_lock);
 305                 return 0;
 306         }
 307
 308         size = ring->wptr + (ring->ring_size / 4);
 309         size -= ptr;
 310         size &= ring->ptr_mask;
 311         if (size == 0) {
 312                 mutex_unlock(&rdev->ring_lock);
 313                 return 0;
 314         }
 315
 316         /* and then save the content of the ring */
 317         *data = kvmalloc_array(size, sizeof(uint32_t), GFP_KERNEL);
 318         if (!*data) {
 319                 mutex_unlock(&rdev->ring_lock);
 320                 return 0;
 321         }
 322         for (i = 0; i < size; ++i) {
 323                 (*data)[i] = ring->ring[ptr++];
 324                 ptr &= ring->ptr_mask;
 325         }
 326
 327         mutex_unlock(&rdev->ring_lock);
 328         return size;
 329 }
 330
 331 /**
 332  * radeon_ring_restore - append saved commands to the ring again
 333  *
 334  * @rdev: radeon_device pointer
 335  * @ring: ring to append commands to
 336  * @size: number of dwords we want to write
 337  * @data: saved commands
 338  *
 339  * Allocates space on the ring and restore the previously saved commands.
 340  */
 341 int radeon_ring_restore(struct radeon_device *rdev, struct radeon_ring *ring,
 342                         unsigned size, uint32_t *data)
 343 {
 344         int i, r;
 345
 346         if (!size || !data)
 347                 return 0;
 348
 349         /* restore the saved ring content */
 350         r = radeon_ring_lock(rdev, ring, size);
 351         if (r)
 352                 return r;
 353
 354         for (i = 0; i < size; ++i) {
 355                 radeon_ring_write(ring, data[i]);
 356         }
 357
 358         radeon_ring_unlock_commit(rdev, ring, false);
 359         kvfree(data);
 360         return 0;
 361 }
 362
 363 /**
 364  * radeon_ring_init - init driver ring struct.
 365  *
 366  * @rdev: radeon_device pointer
 367  * @ring: radeon_ring structure holding ring information
 368  * @ring_size: size of the ring
 369  * @rptr_offs: offset of the rptr writeback location in the WB buffer
 370  * @nop: nop packet for this ring
 371  *
 372  * Initialize the driver information for the selected ring (all asics).
 373  * Returns 0 on success, error on failure.
 374  */
 375 int radeon_ring_init(struct radeon_device *rdev, struct radeon_ring *ring, unsigned ring_size,
 376                      unsigned rptr_offs, u32 nop)
 377 {
 378         int r;
 379
 380         ring->ring_size = ring_size;
 381         ring->rptr_offs = rptr_offs;
 382         ring->nop = nop;
 383         /* Allocate ring buffer */
 384         if (ring->ring_obj == NULL) {
 385                 r = radeon_bo_create(rdev, ring->ring_size, PAGE_SIZE, true,
 386                                      RADEON_GEM_DOMAIN_GTT, 0, NULL,
 387                                      NULL, &ring->ring_obj);
 388                 if (r) {
 389                         dev_err(rdev->dev, "(%d) ring create failed\n", r);
 390                         return r;
 391                 }
 392                 r = radeon_bo_reserve(ring->ring_obj, false);
 393                 if (unlikely(r != 0))
 394                         return r;
 395                 r = radeon_bo_pin(ring->ring_obj, RADEON_GEM_DOMAIN_GTT,
 396                                         &ring->gpu_addr);
 397                 if (r) {
 398                         radeon_bo_unreserve(ring->ring_obj);
 399                         dev_err(rdev->dev, "(%d) ring pin failed\n", r);
 400                         return r;
 401                 }
 402                 r = radeon_bo_kmap(ring->ring_obj,
 403                                        (void **)&ring->ring);
 404                 radeon_bo_unreserve(ring->ring_obj);
 405                 if (r) {
 406                         dev_err(rdev->dev, "(%d) ring map failed\n", r);
 407                         return r;
 408                 }
 409         }
 410         ring->ptr_mask = (ring->ring_size / 4) - 1;
 411         ring->ring_free_dw = ring->ring_size / 4;
 412         if (rdev->wb.enabled) {
 413                 u32 index = RADEON_WB_RING0_NEXT_RPTR + (ring->idx * 4);
 414                 ring->next_rptr_gpu_addr = rdev->wb.gpu_addr + index;
 415                 ring->next_rptr_cpu_addr = &rdev->wb.wb[index/4];
 416         }
 417         if (radeon_debugfs_ring_init(rdev, ring)) {
 418                 DRM_ERROR("Failed to register debugfs file for rings !\n");
 419         }
 420         radeon_ring_lockup_update(rdev, ring);
 421         return 0;
 422 }
 423
 424 /**
 425  * radeon_ring_fini - tear down the driver ring struct.
 426  *
 427  * @rdev: radeon_device pointer
 428  * @ring: radeon_ring structure holding ring information
 429  *
 430  * Tear down the driver information for the selected ring (all asics).
 431  */
 432 void radeon_ring_fini(struct radeon_device *rdev, struct radeon_ring *ring)
 433 {
 434         int r;
 435         struct radeon_bo *ring_obj;
 436
 437         mutex_lock(&rdev->ring_lock);
 438         ring_obj = ring->ring_obj;
 439         ring->ready = false;
 440         ring->ring = NULL;
 441         ring->ring_obj = NULL;
 442         mutex_unlock(&rdev->ring_lock);
 443
 444         if (ring_obj) {
 445                 r = radeon_bo_reserve(ring_obj, false);
 446                 if (likely(r == 0)) {
 447                         radeon_bo_kunmap(ring_obj);
 448                         radeon_bo_unpin(ring_obj);
 449                         radeon_bo_unreserve(ring_obj);
 450                 }
 451                 radeon_bo_unref(&ring_obj);
 452         }
 453 }
 454
 455 /*
 456  * Debugfs info
 457  */
 458 #if defined(CONFIG_DEBUG_FS)
 459
 460 static int radeon_debugfs_ring_info(struct seq_file *m, void *data)
 461 {
 462         struct drm_info_node *node = (struct drm_info_node *) m->private;
 463         struct drm_device *dev = node->minor->dev;
 464         struct radeon_device *rdev = dev->dev_private;
 465         int ridx = *(int*)node->info_ent->data;
 466         struct radeon_ring *ring = &rdev->ring[ridx];
 467
 468         uint32_t rptr, wptr, rptr_next;
 469         unsigned count, i, j;
 470
 471         radeon_ring_free_size(rdev, ring);
 472         count = (ring->ring_size / 4) - ring->ring_free_dw;
 473
 474         wptr = radeon_ring_get_wptr(rdev, ring);
 475         seq_printf(m, "wptr: 0x%08x [%5d]\n",
 476                    wptr, wptr);
 477
 478         rptr = radeon_ring_get_rptr(rdev, ring);
 479         seq_printf(m, "rptr: 0x%08x [%5d]\n",
 480                    rptr, rptr);
 481
 482         if (ring->rptr_save_reg) {
 483                 rptr_next = RREG32(ring->rptr_save_reg);
 484                 seq_printf(m, "rptr next(0x%04x): 0x%08x [%5d]\n",
 485                            ring->rptr_save_reg, rptr_next, rptr_next);
 486         } else
 487                 rptr_next = ~0;
 488
 489         seq_printf(m, "driver's copy of the wptr: 0x%08x [%5d]\n",
 490                    ring->wptr, ring->wptr);
 491         seq_printf(m, "last semaphore signal addr : 0x%016llx\n",
 492                    ring->last_semaphore_signal_addr);
 493         seq_printf(m, "last semaphore wait addr   : 0x%016llx\n",
 494                    ring->last_semaphore_wait_addr);
 495         seq_printf(m, "%u free dwords in ring\n", ring->ring_free_dw);
 496         seq_printf(m, "%u dwords in ring\n", count);
 497
 498         if (!ring->ring)
 499                 return 0;
 500
 501         /* print 8 dw before current rptr as often it's the last executed
 502          * packet that is the root issue
 503          */
 504         i = (rptr + ring->ptr_mask + 1 - 32) & ring->ptr_mask;
 505         for (j = 0; j <= (count + 32); j++) {
 506                 seq_printf(m, "r[%5d]=0x%08x", i, ring->ring[i]);
 507                 if (rptr == i)
 508                         seq_puts(m, " *");
 509                 if (rptr_next == i)
 510                         seq_puts(m, " #");
 511                 seq_puts(m, "\n");
 512                 i = (i + 1) & ring->ptr_mask;
 513         }
 514         return 0;
 515 }
 516
 517 static int radeon_gfx_index = RADEON_RING_TYPE_GFX_INDEX;
 518 static int cayman_cp1_index = CAYMAN_RING_TYPE_CP1_INDEX;
 519 static int cayman_cp2_index = CAYMAN_RING_TYPE_CP2_INDEX;
 520 static int radeon_dma1_index = R600_RING_TYPE_DMA_INDEX;
 521 static int radeon_dma2_index = CAYMAN_RING_TYPE_DMA1_INDEX;
 522 static int r600_uvd_index = R600_RING_TYPE_UVD_INDEX;
 523 static int si_vce1_index = TN_RING_TYPE_VCE1_INDEX;
 524 static int si_vce2_index = TN_RING_TYPE_VCE2_INDEX;
 525
 526 static struct drm_info_list radeon_debugfs_ring_info_list[] = {
 527         {"radeon_ring_gfx", radeon_debugfs_ring_info, 0, &radeon_gfx_index},
 528         {"radeon_ring_cp1", radeon_debugfs_ring_info, 0, &cayman_cp1_index},
 529         {"radeon_ring_cp2", radeon_debugfs_ring_info, 0, &cayman_cp2_index},
 530         {"radeon_ring_dma1", radeon_debugfs_ring_info, 0, &radeon_dma1_index},
 531         {"radeon_ring_dma2", radeon_debugfs_ring_info, 0, &radeon_dma2_index},
 532         {"radeon_ring_uvd", radeon_debugfs_ring_info, 0, &r600_uvd_index},
 533         {"radeon_ring_vce1", radeon_debugfs_ring_info, 0, &si_vce1_index},
 534         {"radeon_ring_vce2", radeon_debugfs_ring_info, 0, &si_vce2_index},
 535 };
 536
 537 #endif
 538
 539 static int radeon_debugfs_ring_init(struct radeon_device *rdev, struct radeon_ring *ring)
 540 {
 541 #if defined(CONFIG_DEBUG_FS)
 542         unsigned i;
 543         for (i = 0; i < ARRAY_SIZE(radeon_debugfs_ring_info_list); ++i) {
 544                 struct drm_info_list *info = &radeon_debugfs_ring_info_list[i];
 545                 int ridx = *(int*)radeon_debugfs_ring_info_list[i].data;
 546                 unsigned r;
 547
 548                 if (&rdev->ring[ridx] != ring)
 549                         continue;
 550
 551                 r = radeon_debugfs_add_files(rdev, info, 1);
 552                 if (r)
 553                         return r;
 554         }
 555 #endif
 556         return 0;
 557 }