1 /** 2 * \file drm_irq.c 3 * IRQ support 4 * 5 * \author Rickard E. (Rik) Faith <faith@valinux.com> 6 * \author Gareth Hughes <gareth@valinux.com> 7 */ 8 9 /* 10 * Created: Fri Mar 19 14:30:16 1999 by faith@valinux.com 11 * 12 * Copyright 1999, 2000 Precision Insight, Inc., Cedar Park, Texas. 13 * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California. 14 * All Rights Reserved. 15 * 16 * Permission is hereby granted, free of charge, to any person obtaining a 17 * copy of this software and associated documentation files (the "Software"), 18 * to deal in the Software without restriction, including without limitation 19 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 20 * and/or sell copies of the Software, and to permit persons to whom the 21 * Software is furnished to do so, subject to the following conditions: 22 * 23 * The above copyright notice and this permission notice (including the next 24 * paragraph) shall be included in all copies or substantial portions of the 25 * Software. 26 * 27 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 28 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 29 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 30 * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR 31 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, 32 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR 33 * OTHER DEALINGS IN THE SOFTWARE. 34 */ 35 36 #include <sys/cdefs.h> 37 __FBSDID("$FreeBSD$"); 38 39 #include <dev/drm2/drmP.h> 40 41 /* Access macro for slots in vblank timestamp ringbuffer. */ 42 #define vblanktimestamp(dev, crtc, count) ( \ 43 (dev)->_vblank_time[(crtc) * DRM_VBLANKTIME_RBSIZE + \ 44 ((count) % DRM_VBLANKTIME_RBSIZE)]) 45 46 /* Retry timestamp calculation up to 3 times to satisfy 47 * drm_timestamp_precision before giving up. 48 */ 49 #define DRM_TIMESTAMP_MAXRETRIES 3 50 51 /* Threshold in nanoseconds for detection of redundant 52 * vblank irq in drm_handle_vblank(). 1 msec should be ok. 53 */ 54 #define DRM_REDUNDANT_VBLIRQ_THRESH_NS 1000000 55 56 /** 57 * Get interrupt from bus id. 58 * 59 * \param inode device inode. 60 * \param file_priv DRM file private. 61 * \param cmd command. 62 * \param arg user argument, pointing to a drm_irq_busid structure. 63 * \return zero on success or a negative number on failure. 64 * 65 * Finds the PCI device with the specified bus id and gets its IRQ number. 66 * This IOCTL is deprecated, and will now return EINVAL for any busid not equal 67 * to that of the device that this DRM instance attached to. 68 */ 69 int drm_irq_by_busid(struct drm_device *dev, void *data, 70 struct drm_file *file_priv) 71 { 72 struct drm_irq_busid *p = data; 73 74 if (!dev->driver->bus->irq_by_busid) 75 return -EINVAL; 76 77 if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ)) 78 return -EINVAL; 79 80 return dev->driver->bus->irq_by_busid(dev, p); 81 } 82 83 /* 84 * Clear vblank timestamp buffer for a crtc. 85 */ 86 static void clear_vblank_timestamps(struct drm_device *dev, int crtc) 87 { 88 memset(&dev->_vblank_time[crtc * DRM_VBLANKTIME_RBSIZE], 0, 89 DRM_VBLANKTIME_RBSIZE * sizeof(struct timeval)); 90 } 91 92 /* 93 * Disable vblank irq's on crtc, make sure that last vblank count 94 * of hardware and corresponding consistent software vblank counter 95 * are preserved, even if there are any spurious vblank irq's after 96 * disable. 97 */ 98 static void vblank_disable_and_save(struct drm_device *dev, int crtc) 99 { 100 u32 vblcount; 101 s64 diff_ns; 102 int vblrc; 103 struct timeval tvblank; 104 int count = DRM_TIMESTAMP_MAXRETRIES; 105 106 /* Prevent vblank irq processing while disabling vblank irqs, 107 * so no updates of timestamps or count can happen after we've 108 * disabled. Needed to prevent races in case of delayed irq's. 109 */ 110 mtx_lock(&dev->vblank_time_lock); 111 112 dev->driver->disable_vblank(dev, crtc); 113 dev->vblank_enabled[crtc] = 0; 114 115 /* No further vblank irq's will be processed after 116 * this point. Get current hardware vblank count and 117 * vblank timestamp, repeat until they are consistent. 118 * 119 * FIXME: There is still a race condition here and in 120 * drm_update_vblank_count() which can cause off-by-one 121 * reinitialization of software vblank counter. If gpu 122 * vblank counter doesn't increment exactly at the leading 123 * edge of a vblank interval, then we can lose 1 count if 124 * we happen to execute between start of vblank and the 125 * delayed gpu counter increment. 126 */ 127 do { 128 dev->last_vblank[crtc] = dev->driver->get_vblank_counter(dev, crtc); 129 vblrc = drm_get_last_vbltimestamp(dev, crtc, &tvblank, 0); 130 } while (dev->last_vblank[crtc] != dev->driver->get_vblank_counter(dev, crtc) && (--count) && vblrc); 131 132 if (!count) 133 vblrc = 0; 134 135 /* Compute time difference to stored timestamp of last vblank 136 * as updated by last invocation of drm_handle_vblank() in vblank irq. 137 */ 138 vblcount = atomic_read(&dev->_vblank_count[crtc]); 139 diff_ns = timeval_to_ns(&tvblank) - 140 timeval_to_ns(&vblanktimestamp(dev, crtc, vblcount)); 141 142 /* If there is at least 1 msec difference between the last stored 143 * timestamp and tvblank, then we are currently executing our 144 * disable inside a new vblank interval, the tvblank timestamp 145 * corresponds to this new vblank interval and the irq handler 146 * for this vblank didn't run yet and won't run due to our disable. 147 * Therefore we need to do the job of drm_handle_vblank() and 148 * increment the vblank counter by one to account for this vblank. 149 * 150 * Skip this step if there isn't any high precision timestamp 151 * available. In that case we can't account for this and just 152 * hope for the best. 153 */ 154 if ((vblrc > 0) && (abs64(diff_ns) > 1000000)) { 155 atomic_inc(&dev->_vblank_count[crtc]); 156 smp_mb__after_atomic_inc(); 157 } 158 159 /* Invalidate all timestamps while vblank irq's are off. */ 160 clear_vblank_timestamps(dev, crtc); 161 162 mtx_unlock(&dev->vblank_time_lock); 163 } 164 165 static void vblank_disable_fn(void *arg) 166 { 167 struct drm_device *dev = (struct drm_device *)arg; 168 int i; 169 170 if (!dev->vblank_disable_allowed) 171 return; 172 173 for (i = 0; i < dev->num_crtcs; i++) { 174 mtx_lock(&dev->vbl_lock); 175 if (atomic_read(&dev->vblank_refcount[i]) == 0 && 176 dev->vblank_enabled[i]) { 177 DRM_DEBUG("disabling vblank on crtc %d\n", i); 178 vblank_disable_and_save(dev, i); 179 } 180 mtx_unlock(&dev->vbl_lock); 181 } 182 } 183 184 void drm_vblank_cleanup(struct drm_device *dev) 185 { 186 /* Bail if the driver didn't call drm_vblank_init() */ 187 if (dev->num_crtcs == 0) 188 return; 189 190 callout_stop(&dev->vblank_disable_callout); 191 192 vblank_disable_fn(dev); 193 194 free(dev->_vblank_count, DRM_MEM_VBLANK); 195 free(dev->vblank_refcount, DRM_MEM_VBLANK); 196 free(dev->vblank_enabled, DRM_MEM_VBLANK); 197 free(dev->last_vblank, DRM_MEM_VBLANK); 198 free(dev->last_vblank_wait, DRM_MEM_VBLANK); 199 free(dev->vblank_inmodeset, DRM_MEM_VBLANK); 200 free(dev->_vblank_time, DRM_MEM_VBLANK); 201 202 mtx_destroy(&dev->vbl_lock); 203 mtx_destroy(&dev->vblank_time_lock); 204 205 dev->num_crtcs = 0; 206 } 207 EXPORT_SYMBOL(drm_vblank_cleanup); 208 209 int drm_vblank_init(struct drm_device *dev, int num_crtcs) 210 { 211 int i, ret = -ENOMEM; 212 213 callout_init(&dev->vblank_disable_callout, 1); 214 mtx_init(&dev->vbl_lock, "drmvbl", NULL, MTX_DEF); 215 mtx_init(&dev->vblank_time_lock, "drmvtl", NULL, MTX_DEF); 216 217 dev->num_crtcs = num_crtcs; 218 219 dev->_vblank_count = malloc(sizeof(atomic_t) * num_crtcs, 220 DRM_MEM_VBLANK, M_NOWAIT); 221 if (!dev->_vblank_count) 222 goto err; 223 224 dev->vblank_refcount = malloc(sizeof(atomic_t) * num_crtcs, 225 DRM_MEM_VBLANK, M_NOWAIT); 226 if (!dev->vblank_refcount) 227 goto err; 228 229 dev->vblank_enabled = malloc(num_crtcs * sizeof(int), 230 DRM_MEM_VBLANK, M_NOWAIT | M_ZERO); 231 if (!dev->vblank_enabled) 232 goto err; 233 234 dev->last_vblank = malloc(num_crtcs * sizeof(u32), 235 DRM_MEM_VBLANK, M_NOWAIT | M_ZERO); 236 if (!dev->last_vblank) 237 goto err; 238 239 dev->last_vblank_wait = malloc(num_crtcs * sizeof(u32), 240 DRM_MEM_VBLANK, M_NOWAIT | M_ZERO); 241 if (!dev->last_vblank_wait) 242 goto err; 243 244 dev->vblank_inmodeset = malloc(num_crtcs * sizeof(int), 245 DRM_MEM_VBLANK, M_NOWAIT | M_ZERO); 246 if (!dev->vblank_inmodeset) 247 goto err; 248 249 dev->_vblank_time = malloc(num_crtcs * DRM_VBLANKTIME_RBSIZE * 250 sizeof(struct timeval), DRM_MEM_VBLANK, M_NOWAIT | M_ZERO); 251 if (!dev->_vblank_time) 252 goto err; 253 254 DRM_INFO("Supports vblank timestamp caching Rev 1 (10.10.2010).\n"); 255 256 /* Driver specific high-precision vblank timestamping supported? */ 257 if (dev->driver->get_vblank_timestamp) 258 DRM_INFO("Driver supports precise vblank timestamp query.\n"); 259 else 260 DRM_INFO("No driver support for vblank timestamp query.\n"); 261 262 /* Zero per-crtc vblank stuff */ 263 for (i = 0; i < num_crtcs; i++) { 264 atomic_set(&dev->_vblank_count[i], 0); 265 atomic_set(&dev->vblank_refcount[i], 0); 266 } 267 268 dev->vblank_disable_allowed = 0; 269 return 0; 270 271 err: 272 drm_vblank_cleanup(dev); 273 return ret; 274 } 275 EXPORT_SYMBOL(drm_vblank_init); 276 277 /** 278 * Install IRQ handler. 279 * 280 * \param dev DRM device. 281 * 282 * Initializes the IRQ related data. Installs the handler, calling the driver 283 * \c irq_preinstall() and \c irq_postinstall() functions 284 * before and after the installation. 285 */ 286 int drm_irq_install(struct drm_device *dev) 287 { 288 int ret; 289 unsigned long sh_flags = 0; 290 291 if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ)) 292 return -EINVAL; 293 294 if (drm_dev_to_irq(dev) == 0) 295 return -EINVAL; 296 297 DRM_LOCK(dev); 298 299 /* Driver must have been initialized */ 300 if (!dev->dev_private) { 301 DRM_UNLOCK(dev); 302 return -EINVAL; 303 } 304 305 if (dev->irq_enabled) { 306 DRM_UNLOCK(dev); 307 return -EBUSY; 308 } 309 dev->irq_enabled = 1; 310 DRM_UNLOCK(dev); 311 312 DRM_DEBUG("irq=%d\n", drm_dev_to_irq(dev)); 313 314 /* Before installing handler */ 315 if (dev->driver->irq_preinstall) 316 dev->driver->irq_preinstall(dev); 317 318 /* Install handler */ 319 sh_flags = INTR_TYPE_TTY | INTR_MPSAFE; 320 if (!drm_core_check_feature(dev, DRIVER_IRQ_SHARED)) 321 /* 322 * FIXME Linux<->FreeBSD: This seems to make 323 * bus_setup_intr() unhappy: it was reported to return 324 * EINVAL on an i915 board (8086:2592 in a Thinkpad 325 * X41). 326 * 327 * For now, no driver we have use that. 328 */ 329 sh_flags |= INTR_EXCL; 330 331 ret = -bus_setup_intr(dev->dev, dev->irqr, sh_flags, NULL, 332 dev->driver->irq_handler, dev, &dev->irqh); 333 334 if (ret < 0) { 335 device_printf(dev->dev, "Error setting interrupt: %d\n", -ret); 336 DRM_LOCK(dev); 337 dev->irq_enabled = 0; 338 DRM_UNLOCK(dev); 339 return ret; 340 } 341 342 /* After installing handler */ 343 if (dev->driver->irq_postinstall) 344 ret = dev->driver->irq_postinstall(dev); 345 346 if (ret < 0) { 347 DRM_LOCK(dev); 348 dev->irq_enabled = 0; 349 DRM_UNLOCK(dev); 350 bus_teardown_intr(dev->dev, dev->irqr, dev->irqh); 351 dev->driver->bus->free_irq(dev); 352 } 353 354 return ret; 355 } 356 EXPORT_SYMBOL(drm_irq_install); 357 358 /** 359 * Uninstall the IRQ handler. 360 * 361 * \param dev DRM device. 362 * 363 * Calls the driver's \c irq_uninstall() function, and stops the irq. 364 */ 365 int drm_irq_uninstall(struct drm_device *dev) 366 { 367 int irq_enabled, i; 368 369 if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ)) 370 return -EINVAL; 371 372 DRM_LOCK(dev); 373 irq_enabled = dev->irq_enabled; 374 dev->irq_enabled = 0; 375 DRM_UNLOCK(dev); 376 377 /* 378 * Wake up any waiters so they don't hang. 379 */ 380 if (dev->num_crtcs) { 381 mtx_lock(&dev->vbl_lock); 382 for (i = 0; i < dev->num_crtcs; i++) { 383 DRM_WAKEUP(&dev->_vblank_count[i]); 384 dev->vblank_enabled[i] = 0; 385 dev->last_vblank[i] = 386 dev->driver->get_vblank_counter(dev, i); 387 } 388 mtx_unlock(&dev->vbl_lock); 389 } 390 391 if (!irq_enabled) 392 return -EINVAL; 393 394 DRM_DEBUG("irq=%d\n", drm_dev_to_irq(dev)); 395 396 if (dev->driver->irq_uninstall) 397 dev->driver->irq_uninstall(dev); 398 399 bus_teardown_intr(dev->dev, dev->irqr, dev->irqh); 400 dev->driver->bus->free_irq(dev); 401 402 return 0; 403 } 404 EXPORT_SYMBOL(drm_irq_uninstall); 405 406 /** 407 * IRQ control ioctl. 408 * 409 * \param inode device inode. 410 * \param file_priv DRM file private. 411 * \param cmd command. 412 * \param arg user argument, pointing to a drm_control structure. 413 * \return zero on success or a negative number on failure. 414 * 415 * Calls irq_install() or irq_uninstall() according to \p arg. 416 */ 417 int drm_control(struct drm_device *dev, void *data, 418 struct drm_file *file_priv) 419 { 420 struct drm_control *ctl = data; 421 422 /* if we haven't irq we fallback for compatibility reasons - 423 * this used to be a separate function in drm_dma.h 424 */ 425 426 427 switch (ctl->func) { 428 case DRM_INST_HANDLER: 429 if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ)) 430 return 0; 431 if (drm_core_check_feature(dev, DRIVER_MODESET)) 432 return 0; 433 if (dev->if_version < DRM_IF_VERSION(1, 2) && 434 ctl->irq != drm_dev_to_irq(dev)) 435 return -EINVAL; 436 return drm_irq_install(dev); 437 case DRM_UNINST_HANDLER: 438 if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ)) 439 return 0; 440 if (drm_core_check_feature(dev, DRIVER_MODESET)) 441 return 0; 442 return drm_irq_uninstall(dev); 443 default: 444 return -EINVAL; 445 } 446 } 447 448 /** 449 * drm_calc_timestamping_constants - Calculate and 450 * store various constants which are later needed by 451 * vblank and swap-completion timestamping, e.g, by 452 * drm_calc_vbltimestamp_from_scanoutpos(). 453 * They are derived from crtc's true scanout timing, 454 * so they take things like panel scaling or other 455 * adjustments into account. 456 * 457 * @crtc drm_crtc whose timestamp constants should be updated. 458 * 459 */ 460 void drm_calc_timestamping_constants(struct drm_crtc *crtc) 461 { 462 s64 linedur_ns = 0, pixeldur_ns = 0, framedur_ns = 0; 463 u64 dotclock; 464 465 /* Dot clock in Hz: */ 466 dotclock = (u64) crtc->hwmode.clock * 1000; 467 468 /* Fields of interlaced scanout modes are only halve a frame duration. 469 * Double the dotclock to get halve the frame-/line-/pixelduration. 470 */ 471 if (crtc->hwmode.flags & DRM_MODE_FLAG_INTERLACE) 472 dotclock *= 2; 473 474 /* Valid dotclock? */ 475 if (dotclock > 0) { 476 /* Convert scanline length in pixels and video dot clock to 477 * line duration, frame duration and pixel duration in 478 * nanoseconds: 479 */ 480 pixeldur_ns = (s64) div64_u64(1000000000, dotclock); 481 linedur_ns = (s64) div64_u64(((u64) crtc->hwmode.crtc_htotal * 482 1000000000), dotclock); 483 framedur_ns = (s64) crtc->hwmode.crtc_vtotal * linedur_ns; 484 } else 485 DRM_ERROR("crtc %d: Can't calculate constants, dotclock = 0!\n", 486 crtc->base.id); 487 488 crtc->pixeldur_ns = pixeldur_ns; 489 crtc->linedur_ns = linedur_ns; 490 crtc->framedur_ns = framedur_ns; 491 492 DRM_DEBUG("crtc %d: hwmode: htotal %d, vtotal %d, vdisplay %d\n", 493 crtc->base.id, crtc->hwmode.crtc_htotal, 494 crtc->hwmode.crtc_vtotal, crtc->hwmode.crtc_vdisplay); 495 DRM_DEBUG("crtc %d: clock %d kHz framedur %d linedur %d, pixeldur %d\n", 496 crtc->base.id, (int) dotclock/1000, (int) framedur_ns, 497 (int) linedur_ns, (int) pixeldur_ns); 498 } 499 EXPORT_SYMBOL(drm_calc_timestamping_constants); 500 501 /** 502 * drm_calc_vbltimestamp_from_scanoutpos - helper routine for kms 503 * drivers. Implements calculation of exact vblank timestamps from 504 * given drm_display_mode timings and current video scanout position 505 * of a crtc. This can be called from within get_vblank_timestamp() 506 * implementation of a kms driver to implement the actual timestamping. 507 * 508 * Should return timestamps conforming to the OML_sync_control OpenML 509 * extension specification. The timestamp corresponds to the end of 510 * the vblank interval, aka start of scanout of topmost-leftmost display 511 * pixel in the following video frame. 512 * 513 * Requires support for optional dev->driver->get_scanout_position() 514 * in kms driver, plus a bit of setup code to provide a drm_display_mode 515 * that corresponds to the true scanout timing. 516 * 517 * The current implementation only handles standard video modes. It 518 * returns as no operation if a doublescan or interlaced video mode is 519 * active. Higher level code is expected to handle this. 520 * 521 * @dev: DRM device. 522 * @crtc: Which crtc's vblank timestamp to retrieve. 523 * @max_error: Desired maximum allowable error in timestamps (nanosecs). 524 * On return contains true maximum error of timestamp. 525 * @vblank_time: Pointer to struct timeval which should receive the timestamp. 526 * @flags: Flags to pass to driver: 527 * 0 = Default. 528 * DRM_CALLED_FROM_VBLIRQ = If function is called from vbl irq handler. 529 * @refcrtc: drm_crtc* of crtc which defines scanout timing. 530 * 531 * Returns negative value on error, failure or if not supported in current 532 * video mode: 533 * 534 * -EINVAL - Invalid crtc. 535 * -EAGAIN - Temporary unavailable, e.g., called before initial modeset. 536 * -ENOTSUPP - Function not supported in current display mode. 537 * -EIO - Failed, e.g., due to failed scanout position query. 538 * 539 * Returns or'ed positive status flags on success: 540 * 541 * DRM_VBLANKTIME_SCANOUTPOS_METHOD - Signal this method used for timestamping. 542 * DRM_VBLANKTIME_INVBL - Timestamp taken while scanout was in vblank interval. 543 * 544 */ 545 int drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev, int crtc, 546 int *max_error, 547 struct timeval *vblank_time, 548 unsigned flags, 549 struct drm_crtc *refcrtc) 550 { 551 struct timeval stime, raw_time; 552 struct drm_display_mode *mode; 553 int vbl_status, vtotal, vdisplay; 554 int vpos, hpos, i; 555 s64 framedur_ns, linedur_ns, pixeldur_ns, delta_ns, duration_ns; 556 bool invbl; 557 558 if (crtc < 0 || crtc >= dev->num_crtcs) { 559 DRM_ERROR("Invalid crtc %d\n", crtc); 560 return -EINVAL; 561 } 562 563 /* Scanout position query not supported? Should not happen. */ 564 if (!dev->driver->get_scanout_position) { 565 DRM_ERROR("Called from driver w/o get_scanout_position()!?\n"); 566 return -EIO; 567 } 568 569 mode = &refcrtc->hwmode; 570 vtotal = mode->crtc_vtotal; 571 vdisplay = mode->crtc_vdisplay; 572 573 /* Durations of frames, lines, pixels in nanoseconds. */ 574 framedur_ns = refcrtc->framedur_ns; 575 linedur_ns = refcrtc->linedur_ns; 576 pixeldur_ns = refcrtc->pixeldur_ns; 577 578 /* If mode timing undefined, just return as no-op: 579 * Happens during initial modesetting of a crtc. 580 */ 581 if (vtotal <= 0 || vdisplay <= 0 || framedur_ns == 0) { 582 DRM_DEBUG("crtc %d: Noop due to uninitialized mode.\n", crtc); 583 return -EAGAIN; 584 } 585 586 /* Get current scanout position with system timestamp. 587 * Repeat query up to DRM_TIMESTAMP_MAXRETRIES times 588 * if single query takes longer than max_error nanoseconds. 589 * 590 * This guarantees a tight bound on maximum error if 591 * code gets preempted or delayed for some reason. 592 */ 593 for (i = 0; i < DRM_TIMESTAMP_MAXRETRIES; i++) { 594 /* Disable preemption to make it very likely to 595 * succeed in the first iteration even on PREEMPT_RT kernel. 596 */ 597 critical_enter(); 598 599 /* Get system timestamp before query. */ 600 getmicrouptime(&stime); 601 602 /* Get vertical and horizontal scanout pos. vpos, hpos. */ 603 vbl_status = dev->driver->get_scanout_position(dev, crtc, &vpos, &hpos); 604 605 /* Get system timestamp after query. */ 606 getmicrouptime(&raw_time); 607 #ifdef FREEBSD_NOTYET 608 if (!drm_timestamp_monotonic) 609 mono_time_offset = ktime_get_monotonic_offset(); 610 #endif /* FREEBSD_NOTYET */ 611 612 critical_exit(); 613 614 /* Return as no-op if scanout query unsupported or failed. */ 615 if (!(vbl_status & DRM_SCANOUTPOS_VALID)) { 616 DRM_DEBUG("crtc %d : scanoutpos query failed [%d].\n", 617 crtc, vbl_status); 618 return -EIO; 619 } 620 621 duration_ns = timeval_to_ns(&raw_time) - timeval_to_ns(&stime); 622 623 /* Accept result with < max_error nsecs timing uncertainty. */ 624 if (duration_ns <= (s64) *max_error) 625 break; 626 } 627 628 /* Noisy system timing? */ 629 if (i == DRM_TIMESTAMP_MAXRETRIES) { 630 DRM_DEBUG("crtc %d: Noisy timestamp %d us > %d us [%d reps].\n", 631 crtc, (int) duration_ns/1000, *max_error/1000, i); 632 } 633 634 /* Return upper bound of timestamp precision error. */ 635 *max_error = (int) duration_ns; 636 637 /* Check if in vblank area: 638 * vpos is >=0 in video scanout area, but negative 639 * within vblank area, counting down the number of lines until 640 * start of scanout. 641 */ 642 invbl = vbl_status & DRM_SCANOUTPOS_INVBL; 643 644 /* Convert scanout position into elapsed time at raw_time query 645 * since start of scanout at first display scanline. delta_ns 646 * can be negative if start of scanout hasn't happened yet. 647 */ 648 delta_ns = (s64) vpos * linedur_ns + (s64) hpos * pixeldur_ns; 649 650 /* Is vpos outside nominal vblank area, but less than 651 * 1/100 of a frame height away from start of vblank? 652 * If so, assume this isn't a massively delayed vblank 653 * interrupt, but a vblank interrupt that fired a few 654 * microseconds before true start of vblank. Compensate 655 * by adding a full frame duration to the final timestamp. 656 * Happens, e.g., on ATI R500, R600. 657 * 658 * We only do this if DRM_CALLED_FROM_VBLIRQ. 659 */ 660 if ((flags & DRM_CALLED_FROM_VBLIRQ) && !invbl && 661 ((vdisplay - vpos) < vtotal / 100)) { 662 delta_ns = delta_ns - framedur_ns; 663 664 /* Signal this correction as "applied". */ 665 vbl_status |= 0x8; 666 } 667 668 #ifdef FREEBSD_NOTYET 669 if (!drm_timestamp_monotonic) 670 etime = ktime_sub(etime, mono_time_offset); 671 672 /* save this only for debugging purposes */ 673 tv_etime = ktime_to_timeval(etime); 674 #endif /* FREEBSD_NOTYET */ 675 /* Subtract time delta from raw timestamp to get final 676 * vblank_time timestamp for end of vblank. 677 */ 678 *vblank_time = ns_to_timeval(timeval_to_ns(&raw_time) - delta_ns); 679 680 DRM_DEBUG("crtc %d : v %d p(%d,%d)@ %jd.%jd -> %jd.%jd [e %d us, %d rep]\n", 681 crtc, (int)vbl_status, hpos, vpos, (uintmax_t)raw_time.tv_sec, 682 (uintmax_t)raw_time.tv_usec, (uintmax_t)vblank_time->tv_sec, 683 (uintmax_t)vblank_time->tv_usec, (int)duration_ns/1000, i); 684 685 vbl_status = DRM_VBLANKTIME_SCANOUTPOS_METHOD; 686 if (invbl) 687 vbl_status |= DRM_VBLANKTIME_INVBL; 688 689 return vbl_status; 690 } 691 EXPORT_SYMBOL(drm_calc_vbltimestamp_from_scanoutpos); 692 693 static struct timeval get_drm_timestamp(void) 694 { 695 struct timeval now; 696 697 microtime(&now); 698 #ifdef FREEBSD_NOTYET 699 if (!drm_timestamp_monotonic) 700 now = ktime_sub(now, ktime_get_monotonic_offset()); 701 #endif /* defined(FREEBSD_NOTYET) */ 702 703 return now; 704 } 705 706 /** 707 * drm_get_last_vbltimestamp - retrieve raw timestamp for the most recent 708 * vblank interval. 709 * 710 * @dev: DRM device 711 * @crtc: which crtc's vblank timestamp to retrieve 712 * @tvblank: Pointer to target struct timeval which should receive the timestamp 713 * @flags: Flags to pass to driver: 714 * 0 = Default. 715 * DRM_CALLED_FROM_VBLIRQ = If function is called from vbl irq handler. 716 * 717 * Fetches the system timestamp corresponding to the time of the most recent 718 * vblank interval on specified crtc. May call into kms-driver to 719 * compute the timestamp with a high-precision GPU specific method. 720 * 721 * Returns zero if timestamp originates from uncorrected do_gettimeofday() 722 * call, i.e., it isn't very precisely locked to the true vblank. 723 * 724 * Returns non-zero if timestamp is considered to be very precise. 725 */ 726 u32 drm_get_last_vbltimestamp(struct drm_device *dev, int crtc, 727 struct timeval *tvblank, unsigned flags) 728 { 729 int ret; 730 731 /* Define requested maximum error on timestamps (nanoseconds). */ 732 int max_error = (int) drm_timestamp_precision * 1000; 733 734 /* Query driver if possible and precision timestamping enabled. */ 735 if (dev->driver->get_vblank_timestamp && (max_error > 0)) { 736 ret = dev->driver->get_vblank_timestamp(dev, crtc, &max_error, 737 tvblank, flags); 738 if (ret > 0) 739 return (u32) ret; 740 } 741 742 /* GPU high precision timestamp query unsupported or failed. 743 * Return current monotonic/gettimeofday timestamp as best estimate. 744 */ 745 *tvblank = get_drm_timestamp(); 746 747 return 0; 748 } 749 EXPORT_SYMBOL(drm_get_last_vbltimestamp); 750 751 /** 752 * drm_vblank_count - retrieve "cooked" vblank counter value 753 * @dev: DRM device 754 * @crtc: which counter to retrieve 755 * 756 * Fetches the "cooked" vblank count value that represents the number of 757 * vblank events since the system was booted, including lost events due to 758 * modesetting activity. 759 */ 760 u32 drm_vblank_count(struct drm_device *dev, int crtc) 761 { 762 return atomic_read(&dev->_vblank_count[crtc]); 763 } 764 EXPORT_SYMBOL(drm_vblank_count); 765 766 /** 767 * drm_vblank_count_and_time - retrieve "cooked" vblank counter value 768 * and the system timestamp corresponding to that vblank counter value. 769 * 770 * @dev: DRM device 771 * @crtc: which counter to retrieve 772 * @vblanktime: Pointer to struct timeval to receive the vblank timestamp. 773 * 774 * Fetches the "cooked" vblank count value that represents the number of 775 * vblank events since the system was booted, including lost events due to 776 * modesetting activity. Returns corresponding system timestamp of the time 777 * of the vblank interval that corresponds to the current value vblank counter 778 * value. 779 */ 780 u32 drm_vblank_count_and_time(struct drm_device *dev, int crtc, 781 struct timeval *vblanktime) 782 { 783 u32 cur_vblank; 784 785 /* Read timestamp from slot of _vblank_time ringbuffer 786 * that corresponds to current vblank count. Retry if 787 * count has incremented during readout. This works like 788 * a seqlock. 789 */ 790 do { 791 cur_vblank = atomic_read(&dev->_vblank_count[crtc]); 792 *vblanktime = vblanktimestamp(dev, crtc, cur_vblank); 793 smp_rmb(); 794 } while (cur_vblank != atomic_read(&dev->_vblank_count[crtc])); 795 796 return cur_vblank; 797 } 798 EXPORT_SYMBOL(drm_vblank_count_and_time); 799 800 static void send_vblank_event(struct drm_device *dev, 801 struct drm_pending_vblank_event *e, 802 unsigned long seq, struct timeval *now) 803 { 804 WARN_ON_SMP(!mtx_owned(&dev->event_lock)); 805 e->event.sequence = seq; 806 e->event.tv_sec = now->tv_sec; 807 e->event.tv_usec = now->tv_usec; 808 809 list_add_tail(&e->base.link, 810 &e->base.file_priv->event_list); 811 drm_event_wakeup(&e->base); 812 CTR3(KTR_DRM, "vblank_event_delivered %d %d %d", 813 e->base.pid, e->pipe, e->event.sequence); 814 } 815 816 /** 817 * drm_send_vblank_event - helper to send vblank event after pageflip 818 * @dev: DRM device 819 * @crtc: CRTC in question 820 * @e: the event to send 821 * 822 * Updates sequence # and timestamp on event, and sends it to userspace. 823 * Caller must hold event lock. 824 */ 825 void drm_send_vblank_event(struct drm_device *dev, int crtc, 826 struct drm_pending_vblank_event *e) 827 { 828 struct timeval now; 829 unsigned int seq; 830 if (crtc >= 0) { 831 seq = drm_vblank_count_and_time(dev, crtc, &now); 832 } else { 833 seq = 0; 834 835 now = get_drm_timestamp(); 836 } 837 send_vblank_event(dev, e, seq, &now); 838 } 839 EXPORT_SYMBOL(drm_send_vblank_event); 840 841 /** 842 * drm_update_vblank_count - update the master vblank counter 843 * @dev: DRM device 844 * @crtc: counter to update 845 * 846 * Call back into the driver to update the appropriate vblank counter 847 * (specified by @crtc). Deal with wraparound, if it occurred, and 848 * update the last read value so we can deal with wraparound on the next 849 * call if necessary. 850 * 851 * Only necessary when going from off->on, to account for frames we 852 * didn't get an interrupt for. 853 * 854 * Note: caller must hold dev->vbl_lock since this reads & writes 855 * device vblank fields. 856 */ 857 static void drm_update_vblank_count(struct drm_device *dev, int crtc) 858 { 859 u32 cur_vblank, diff, tslot, rc; 860 struct timeval t_vblank; 861 862 /* 863 * Interrupts were disabled prior to this call, so deal with counter 864 * wrap if needed. 865 * NOTE! It's possible we lost a full dev->max_vblank_count events 866 * here if the register is small or we had vblank interrupts off for 867 * a long time. 868 * 869 * We repeat the hardware vblank counter & timestamp query until 870 * we get consistent results. This to prevent races between gpu 871 * updating its hardware counter while we are retrieving the 872 * corresponding vblank timestamp. 873 */ 874 do { 875 cur_vblank = dev->driver->get_vblank_counter(dev, crtc); 876 rc = drm_get_last_vbltimestamp(dev, crtc, &t_vblank, 0); 877 } while (cur_vblank != dev->driver->get_vblank_counter(dev, crtc)); 878 879 /* Deal with counter wrap */ 880 diff = cur_vblank - dev->last_vblank[crtc]; 881 if (cur_vblank < dev->last_vblank[crtc]) { 882 diff += dev->max_vblank_count; 883 884 DRM_DEBUG("last_vblank[%d]=0x%x, cur_vblank=0x%x => diff=0x%x\n", 885 crtc, dev->last_vblank[crtc], cur_vblank, diff); 886 } 887 888 DRM_DEBUG("enabling vblank interrupts on crtc %d, missed %d\n", 889 crtc, diff); 890 891 /* Reinitialize corresponding vblank timestamp if high-precision query 892 * available. Skip this step if query unsupported or failed. Will 893 * reinitialize delayed at next vblank interrupt in that case. 894 */ 895 if (rc) { 896 tslot = atomic_read(&dev->_vblank_count[crtc]) + diff; 897 vblanktimestamp(dev, crtc, tslot) = t_vblank; 898 } 899 900 smp_mb__before_atomic_inc(); 901 atomic_add(diff, &dev->_vblank_count[crtc]); 902 smp_mb__after_atomic_inc(); 903 } 904 905 /** 906 * drm_vblank_get - get a reference count on vblank events 907 * @dev: DRM device 908 * @crtc: which CRTC to own 909 * 910 * Acquire a reference count on vblank events to avoid having them disabled 911 * while in use. 912 * 913 * RETURNS 914 * Zero on success, nonzero on failure. 915 */ 916 int drm_vblank_get(struct drm_device *dev, int crtc) 917 { 918 int ret = 0; 919 920 mtx_lock(&dev->vbl_lock); 921 /* Going from 0->1 means we have to enable interrupts again */ 922 if (atomic_add_return(1, &dev->vblank_refcount[crtc]) == 1) { 923 mtx_lock(&dev->vblank_time_lock); 924 if (!dev->vblank_enabled[crtc]) { 925 /* Enable vblank irqs under vblank_time_lock protection. 926 * All vblank count & timestamp updates are held off 927 * until we are done reinitializing master counter and 928 * timestamps. Filtercode in drm_handle_vblank() will 929 * prevent double-accounting of same vblank interval. 930 */ 931 ret = dev->driver->enable_vblank(dev, crtc); 932 DRM_DEBUG("enabling vblank on crtc %d, ret: %d\n", 933 crtc, ret); 934 if (ret) 935 atomic_dec(&dev->vblank_refcount[crtc]); 936 else { 937 dev->vblank_enabled[crtc] = 1; 938 drm_update_vblank_count(dev, crtc); 939 } 940 } 941 mtx_unlock(&dev->vblank_time_lock); 942 } else { 943 if (!dev->vblank_enabled[crtc]) { 944 atomic_dec(&dev->vblank_refcount[crtc]); 945 ret = -EINVAL; 946 } 947 } 948 mtx_unlock(&dev->vbl_lock); 949 950 return ret; 951 } 952 EXPORT_SYMBOL(drm_vblank_get); 953 954 /** 955 * drm_vblank_put - give up ownership of vblank events 956 * @dev: DRM device 957 * @crtc: which counter to give up 958 * 959 * Release ownership of a given vblank counter, turning off interrupts 960 * if possible. Disable interrupts after drm_vblank_offdelay milliseconds. 961 */ 962 void drm_vblank_put(struct drm_device *dev, int crtc) 963 { 964 BUG_ON(atomic_read(&dev->vblank_refcount[crtc]) == 0); 965 966 /* Last user schedules interrupt disable */ 967 if (atomic_dec_and_test(&dev->vblank_refcount[crtc]) && 968 (drm_vblank_offdelay > 0)) 969 callout_reset(&dev->vblank_disable_callout, 970 (drm_vblank_offdelay * DRM_HZ) / 1000, 971 vblank_disable_fn, dev); 972 } 973 EXPORT_SYMBOL(drm_vblank_put); 974 975 /** 976 * drm_vblank_off - disable vblank events on a CRTC 977 * @dev: DRM device 978 * @crtc: CRTC in question 979 * 980 * Caller must hold event lock. 981 */ 982 void drm_vblank_off(struct drm_device *dev, int crtc) 983 { 984 struct drm_pending_vblank_event *e, *t; 985 struct timeval now; 986 unsigned int seq; 987 988 mtx_lock(&dev->vbl_lock); 989 vblank_disable_and_save(dev, crtc); 990 DRM_WAKEUP(&dev->_vblank_count[crtc]); 991 992 /* Send any queued vblank events, lest the natives grow disquiet */ 993 seq = drm_vblank_count_and_time(dev, crtc, &now); 994 995 mtx_lock(&dev->event_lock); 996 list_for_each_entry_safe(e, t, &dev->vblank_event_list, base.link) { 997 if (e->pipe != crtc) 998 continue; 999 DRM_DEBUG("Sending premature vblank event on disable: \ 1000 wanted %d, current %d\n", 1001 e->event.sequence, seq); 1002 list_del(&e->base.link); 1003 drm_vblank_put(dev, e->pipe); 1004 send_vblank_event(dev, e, seq, &now); 1005 } 1006 mtx_unlock(&dev->event_lock); 1007 1008 mtx_unlock(&dev->vbl_lock); 1009 } 1010 EXPORT_SYMBOL(drm_vblank_off); 1011 1012 /** 1013 * drm_vblank_pre_modeset - account for vblanks across mode sets 1014 * @dev: DRM device 1015 * @crtc: CRTC in question 1016 * 1017 * Account for vblank events across mode setting events, which will likely 1018 * reset the hardware frame counter. 1019 */ 1020 void drm_vblank_pre_modeset(struct drm_device *dev, int crtc) 1021 { 1022 /* vblank is not initialized (IRQ not installed ?), or has been freed */ 1023 if (!dev->num_crtcs) 1024 return; 1025 /* 1026 * To avoid all the problems that might happen if interrupts 1027 * were enabled/disabled around or between these calls, we just 1028 * have the kernel take a reference on the CRTC (just once though 1029 * to avoid corrupting the count if multiple, mismatch calls occur), 1030 * so that interrupts remain enabled in the interim. 1031 */ 1032 if (!dev->vblank_inmodeset[crtc]) { 1033 dev->vblank_inmodeset[crtc] = 0x1; 1034 if (drm_vblank_get(dev, crtc) == 0) 1035 dev->vblank_inmodeset[crtc] |= 0x2; 1036 } 1037 } 1038 EXPORT_SYMBOL(drm_vblank_pre_modeset); 1039 1040 void drm_vblank_post_modeset(struct drm_device *dev, int crtc) 1041 { 1042 /* vblank is not initialized (IRQ not installed ?), or has been freed */ 1043 if (!dev->num_crtcs) 1044 return; 1045 1046 if (dev->vblank_inmodeset[crtc]) { 1047 mtx_lock(&dev->vbl_lock); 1048 dev->vblank_disable_allowed = 1; 1049 mtx_unlock(&dev->vbl_lock); 1050 1051 if (dev->vblank_inmodeset[crtc] & 0x2) 1052 drm_vblank_put(dev, crtc); 1053 1054 dev->vblank_inmodeset[crtc] = 0; 1055 } 1056 } 1057 EXPORT_SYMBOL(drm_vblank_post_modeset); 1058 1059 /** 1060 * drm_modeset_ctl - handle vblank event counter changes across mode switch 1061 * @DRM_IOCTL_ARGS: standard ioctl arguments 1062 * 1063 * Applications should call the %_DRM_PRE_MODESET and %_DRM_POST_MODESET 1064 * ioctls around modesetting so that any lost vblank events are accounted for. 1065 * 1066 * Generally the counter will reset across mode sets. If interrupts are 1067 * enabled around this call, we don't have to do anything since the counter 1068 * will have already been incremented. 1069 */ 1070 int drm_modeset_ctl(struct drm_device *dev, void *data, 1071 struct drm_file *file_priv) 1072 { 1073 struct drm_modeset_ctl *modeset = data; 1074 unsigned int crtc; 1075 1076 /* If drm_vblank_init() hasn't been called yet, just no-op */ 1077 if (!dev->num_crtcs) 1078 return 0; 1079 1080 /* KMS drivers handle this internally */ 1081 if (drm_core_check_feature(dev, DRIVER_MODESET)) 1082 return 0; 1083 1084 crtc = modeset->crtc; 1085 if (crtc >= dev->num_crtcs) 1086 return -EINVAL; 1087 1088 switch (modeset->cmd) { 1089 case _DRM_PRE_MODESET: 1090 drm_vblank_pre_modeset(dev, crtc); 1091 break; 1092 case _DRM_POST_MODESET: 1093 drm_vblank_post_modeset(dev, crtc); 1094 break; 1095 default: 1096 return -EINVAL; 1097 } 1098 1099 return 0; 1100 } 1101 1102 static void 1103 drm_vblank_event_destroy(struct drm_pending_event *e) 1104 { 1105 1106 free(e, DRM_MEM_VBLANK); 1107 } 1108 1109 static int drm_queue_vblank_event(struct drm_device *dev, int pipe, 1110 union drm_wait_vblank *vblwait, 1111 struct drm_file *file_priv) 1112 { 1113 struct drm_pending_vblank_event *e; 1114 struct timeval now; 1115 unsigned int seq; 1116 int ret; 1117 1118 e = malloc(sizeof *e, DRM_MEM_VBLANK, M_NOWAIT | M_ZERO); 1119 if (e == NULL) { 1120 ret = -ENOMEM; 1121 goto err_put; 1122 } 1123 1124 e->pipe = pipe; 1125 e->base.pid = curproc->p_pid; 1126 e->event.base.type = DRM_EVENT_VBLANK; 1127 e->event.base.length = sizeof e->event; 1128 e->event.user_data = vblwait->request.signal; 1129 e->base.event = &e->event.base; 1130 e->base.file_priv = file_priv; 1131 e->base.destroy = drm_vblank_event_destroy; 1132 1133 mtx_lock(&dev->event_lock); 1134 1135 if (file_priv->event_space < sizeof e->event) { 1136 ret = -EBUSY; 1137 goto err_unlock; 1138 } 1139 1140 file_priv->event_space -= sizeof e->event; 1141 seq = drm_vblank_count_and_time(dev, pipe, &now); 1142 1143 if ((vblwait->request.type & _DRM_VBLANK_NEXTONMISS) && 1144 (seq - vblwait->request.sequence) <= (1 << 23)) { 1145 vblwait->request.sequence = seq + 1; 1146 vblwait->reply.sequence = vblwait->request.sequence; 1147 } 1148 1149 DRM_DEBUG("event on vblank count %d, current %d, crtc %d\n", 1150 vblwait->request.sequence, seq, pipe); 1151 1152 CTR4(KTR_DRM, "vblank_event_queued %d %d rt %x %d", curproc->p_pid, pipe, 1153 vblwait->request.type, vblwait->request.sequence); 1154 1155 e->event.sequence = vblwait->request.sequence; 1156 if ((seq - vblwait->request.sequence) <= (1 << 23)) { 1157 drm_vblank_put(dev, pipe); 1158 send_vblank_event(dev, e, seq, &now); 1159 vblwait->reply.sequence = seq; 1160 } else { 1161 /* drm_handle_vblank_events will call drm_vblank_put */ 1162 list_add_tail(&e->base.link, &dev->vblank_event_list); 1163 vblwait->reply.sequence = vblwait->request.sequence; 1164 } 1165 1166 mtx_unlock(&dev->event_lock); 1167 1168 return 0; 1169 1170 err_unlock: 1171 mtx_unlock(&dev->event_lock); 1172 free(e, DRM_MEM_VBLANK); 1173 err_put: 1174 drm_vblank_put(dev, pipe); 1175 return ret; 1176 } 1177 1178 /** 1179 * Wait for VBLANK. 1180 * 1181 * \param inode device inode. 1182 * \param file_priv DRM file private. 1183 * \param cmd command. 1184 * \param data user argument, pointing to a drm_wait_vblank structure. 1185 * \return zero on success or a negative number on failure. 1186 * 1187 * This function enables the vblank interrupt on the pipe requested, then 1188 * sleeps waiting for the requested sequence number to occur, and drops 1189 * the vblank interrupt refcount afterwards. (vblank irq disable follows that 1190 * after a timeout with no further vblank waits scheduled). 1191 */ 1192 int drm_wait_vblank(struct drm_device *dev, void *data, 1193 struct drm_file *file_priv) 1194 { 1195 union drm_wait_vblank *vblwait = data; 1196 int ret; 1197 unsigned int flags, seq, crtc, high_crtc; 1198 1199 if (/*(!drm_dev_to_irq(dev)) || */(!dev->irq_enabled)) 1200 return -EINVAL; 1201 1202 if (vblwait->request.type & _DRM_VBLANK_SIGNAL) 1203 return -EINVAL; 1204 1205 if (vblwait->request.type & 1206 ~(_DRM_VBLANK_TYPES_MASK | _DRM_VBLANK_FLAGS_MASK | 1207 _DRM_VBLANK_HIGH_CRTC_MASK)) { 1208 DRM_ERROR("Unsupported type value 0x%x, supported mask 0x%x\n", 1209 vblwait->request.type, 1210 (_DRM_VBLANK_TYPES_MASK | _DRM_VBLANK_FLAGS_MASK | 1211 _DRM_VBLANK_HIGH_CRTC_MASK)); 1212 return -EINVAL; 1213 } 1214 1215 flags = vblwait->request.type & _DRM_VBLANK_FLAGS_MASK; 1216 high_crtc = (vblwait->request.type & _DRM_VBLANK_HIGH_CRTC_MASK); 1217 if (high_crtc) 1218 crtc = high_crtc >> _DRM_VBLANK_HIGH_CRTC_SHIFT; 1219 else 1220 crtc = flags & _DRM_VBLANK_SECONDARY ? 1 : 0; 1221 if (crtc >= dev->num_crtcs) 1222 return -EINVAL; 1223 1224 ret = drm_vblank_get(dev, crtc); 1225 if (ret) { 1226 DRM_DEBUG("failed to acquire vblank counter, %d\n", ret); 1227 return ret; 1228 } 1229 seq = drm_vblank_count(dev, crtc); 1230 1231 switch (vblwait->request.type & _DRM_VBLANK_TYPES_MASK) { 1232 case _DRM_VBLANK_RELATIVE: 1233 vblwait->request.sequence += seq; 1234 vblwait->request.type &= ~_DRM_VBLANK_RELATIVE; 1235 case _DRM_VBLANK_ABSOLUTE: 1236 break; 1237 default: 1238 ret = -EINVAL; 1239 goto done; 1240 } 1241 1242 if (flags & _DRM_VBLANK_EVENT) { 1243 /* must hold on to the vblank ref until the event fires 1244 * drm_vblank_put will be called asynchronously 1245 */ 1246 return drm_queue_vblank_event(dev, crtc, vblwait, file_priv); 1247 } 1248 1249 if ((flags & _DRM_VBLANK_NEXTONMISS) && 1250 (seq - vblwait->request.sequence) <= (1<<23)) { 1251 vblwait->request.sequence = seq + 1; 1252 } 1253 1254 DRM_DEBUG("waiting on vblank count %d, crtc %d\n", 1255 vblwait->request.sequence, crtc); 1256 dev->last_vblank_wait[crtc] = vblwait->request.sequence; 1257 mtx_lock(&dev->vblank_time_lock); 1258 while (((drm_vblank_count(dev, crtc) - vblwait->request.sequence) > 1259 (1 << 23)) && dev->irq_enabled) { 1260 /* 1261 * The wakeups from the drm_irq_uninstall() and 1262 * drm_vblank_off() may be lost there since vbl_lock 1263 * is not held. Then, the timeout will wake us; the 3 1264 * seconds delay should not be a problem for 1265 * application when crtc is disabled or irq 1266 * uninstalled anyway. 1267 */ 1268 ret = -msleep(&dev->_vblank_count[crtc], &dev->vblank_time_lock, 1269 PCATCH, "drmvbl", 3 * hz); 1270 if (ret == -ERESTART) 1271 ret = -ERESTARTSYS; 1272 if (ret != 0) 1273 break; 1274 } 1275 mtx_unlock(&dev->vblank_time_lock); 1276 if (ret != -EINTR) { 1277 struct timeval now; 1278 long reply_seq; 1279 1280 reply_seq = drm_vblank_count_and_time(dev, crtc, &now); 1281 CTR5(KTR_DRM, "wait_vblank %d %d rt %x success %d %d", 1282 curproc->p_pid, crtc, vblwait->request.type, 1283 vblwait->request.sequence, reply_seq); 1284 1285 vblwait->reply.sequence = reply_seq; 1286 vblwait->reply.tval_sec = now.tv_sec; 1287 vblwait->reply.tval_usec = now.tv_usec; 1288 1289 DRM_DEBUG("returning %d to client\n", 1290 vblwait->reply.sequence); 1291 } else { 1292 CTR5(KTR_DRM, "wait_vblank %d %d rt %x error %d %d", 1293 curproc->p_pid, crtc, vblwait->request.type, ret, 1294 vblwait->request.sequence); 1295 1296 DRM_DEBUG("vblank wait interrupted by signal\n"); 1297 } 1298 1299 done: 1300 drm_vblank_put(dev, crtc); 1301 return ret; 1302 } 1303 1304 static void drm_handle_vblank_events(struct drm_device *dev, int crtc) 1305 { 1306 struct drm_pending_vblank_event *e, *t; 1307 struct timeval now; 1308 unsigned int seq; 1309 1310 seq = drm_vblank_count_and_time(dev, crtc, &now); 1311 1312 mtx_lock(&dev->event_lock); 1313 1314 list_for_each_entry_safe(e, t, &dev->vblank_event_list, base.link) { 1315 if (e->pipe != crtc) 1316 continue; 1317 if ((seq - e->event.sequence) > (1<<23)) 1318 continue; 1319 1320 DRM_DEBUG("vblank event on %d, current %d\n", 1321 e->event.sequence, seq); 1322 1323 list_del(&e->base.link); 1324 drm_vblank_put(dev, e->pipe); 1325 send_vblank_event(dev, e, seq, &now); 1326 } 1327 1328 mtx_unlock(&dev->event_lock); 1329 1330 CTR2(KTR_DRM, "drm_handle_vblank_events %d %d", seq, crtc); 1331 } 1332 1333 /** 1334 * drm_handle_vblank - handle a vblank event 1335 * @dev: DRM device 1336 * @crtc: where this event occurred 1337 * 1338 * Drivers should call this routine in their vblank interrupt handlers to 1339 * update the vblank counter and send any signals that may be pending. 1340 */ 1341 bool drm_handle_vblank(struct drm_device *dev, int crtc) 1342 { 1343 u32 vblcount; 1344 s64 diff_ns; 1345 struct timeval tvblank; 1346 1347 if (!dev->num_crtcs) 1348 return false; 1349 1350 /* Need timestamp lock to prevent concurrent execution with 1351 * vblank enable/disable, as this would cause inconsistent 1352 * or corrupted timestamps and vblank counts. 1353 */ 1354 mtx_lock(&dev->vblank_time_lock); 1355 1356 /* Vblank irq handling disabled. Nothing to do. */ 1357 if (!dev->vblank_enabled[crtc]) { 1358 mtx_unlock(&dev->vblank_time_lock); 1359 return false; 1360 } 1361 1362 /* Fetch corresponding timestamp for this vblank interval from 1363 * driver and store it in proper slot of timestamp ringbuffer. 1364 */ 1365 1366 /* Get current timestamp and count. */ 1367 vblcount = atomic_read(&dev->_vblank_count[crtc]); 1368 drm_get_last_vbltimestamp(dev, crtc, &tvblank, DRM_CALLED_FROM_VBLIRQ); 1369 1370 /* Compute time difference to timestamp of last vblank */ 1371 diff_ns = timeval_to_ns(&tvblank) - 1372 timeval_to_ns(&vblanktimestamp(dev, crtc, vblcount)); 1373 1374 /* Update vblank timestamp and count if at least 1375 * DRM_REDUNDANT_VBLIRQ_THRESH_NS nanoseconds 1376 * difference between last stored timestamp and current 1377 * timestamp. A smaller difference means basically 1378 * identical timestamps. Happens if this vblank has 1379 * been already processed and this is a redundant call, 1380 * e.g., due to spurious vblank interrupts. We need to 1381 * ignore those for accounting. 1382 */ 1383 if (abs64(diff_ns) > DRM_REDUNDANT_VBLIRQ_THRESH_NS) { 1384 /* Store new timestamp in ringbuffer. */ 1385 vblanktimestamp(dev, crtc, vblcount + 1) = tvblank; 1386 1387 /* Increment cooked vblank count. This also atomically commits 1388 * the timestamp computed above. 1389 */ 1390 smp_mb__before_atomic_inc(); 1391 atomic_inc(&dev->_vblank_count[crtc]); 1392 smp_mb__after_atomic_inc(); 1393 } else { 1394 DRM_DEBUG("crtc %d: Redundant vblirq ignored. diff_ns = %d\n", 1395 crtc, (int) diff_ns); 1396 } 1397 1398 DRM_WAKEUP(&dev->_vblank_count[crtc]); 1399 drm_handle_vblank_events(dev, crtc); 1400 1401 mtx_unlock(&dev->vblank_time_lock); 1402 return true; 1403 } 1404 EXPORT_SYMBOL(drm_handle_vblank); 1405