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 "drmP.h" 37 38 #include <linux/interrupt.h> /* For task queue support */ 39 40 /** 41 * Get interrupt from bus id. 42 * 43 * \param inode device inode. 44 * \param file_priv DRM file private. 45 * \param cmd command. 46 * \param arg user argument, pointing to a drm_irq_busid structure. 47 * \return zero on success or a negative number on failure. 48 * 49 * Finds the PCI device with the specified bus id and gets its IRQ number. 50 * This IOCTL is deprecated, and will now return EINVAL for any busid not equal 51 * to that of the device that this DRM instance attached to. 52 */ 53 int drm_irq_by_busid(struct drm_device *dev, void *data, 54 struct drm_file *file_priv) 55 { 56 struct drm_irq_busid *p = data; 57 58 if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ)) 59 return -EINVAL; 60 61 if ((p->busnum >> 8) != drm_get_pci_domain(dev) || 62 (p->busnum & 0xff) != dev->pdev->bus->number || 63 p->devnum != PCI_SLOT(dev->pdev->devfn) || p->funcnum != PCI_FUNC(dev->pdev->devfn)) 64 return -EINVAL; 65 66 p->irq = dev->irq; 67 68 DRM_DEBUG("%d:%d:%d => IRQ %d\n", p->busnum, p->devnum, p->funcnum, 69 p->irq); 70 71 return 0; 72 } 73 74 /** 75 * Install IRQ handler. 76 * 77 * \param dev DRM device. 78 * \param irq IRQ number. 79 * 80 * Initializes the IRQ related data, and setups drm_device::vbl_queue. Installs the handler, calling the driver 81 * \c drm_driver_irq_preinstall() and \c drm_driver_irq_postinstall() functions 82 * before and after the installation. 83 */ 84 static int drm_irq_install(struct drm_device * dev) 85 { 86 int ret; 87 unsigned long sh_flags = 0; 88 89 if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ)) 90 return -EINVAL; 91 92 if (dev->irq == 0) 93 return -EINVAL; 94 95 mutex_lock(&dev->struct_mutex); 96 97 /* Driver must have been initialized */ 98 if (!dev->dev_private) { 99 mutex_unlock(&dev->struct_mutex); 100 return -EINVAL; 101 } 102 103 if (dev->irq_enabled) { 104 mutex_unlock(&dev->struct_mutex); 105 return -EBUSY; 106 } 107 dev->irq_enabled = 1; 108 mutex_unlock(&dev->struct_mutex); 109 110 DRM_DEBUG("irq=%d\n", dev->irq); 111 112 if (drm_core_check_feature(dev, DRIVER_IRQ_VBL)) { 113 init_waitqueue_head(&dev->vbl_queue); 114 115 spin_lock_init(&dev->vbl_lock); 116 117 INIT_LIST_HEAD(&dev->vbl_sigs); 118 INIT_LIST_HEAD(&dev->vbl_sigs2); 119 120 dev->vbl_pending = 0; 121 } 122 123 /* Before installing handler */ 124 dev->driver->irq_preinstall(dev); 125 126 /* Install handler */ 127 if (drm_core_check_feature(dev, DRIVER_IRQ_SHARED)) 128 sh_flags = IRQF_SHARED; 129 130 ret = request_irq(dev->irq, dev->driver->irq_handler, 131 sh_flags, dev->devname, dev); 132 if (ret < 0) { 133 mutex_lock(&dev->struct_mutex); 134 dev->irq_enabled = 0; 135 mutex_unlock(&dev->struct_mutex); 136 return ret; 137 } 138 139 /* After installing handler */ 140 dev->driver->irq_postinstall(dev); 141 142 return 0; 143 } 144 145 /** 146 * Uninstall the IRQ handler. 147 * 148 * \param dev DRM device. 149 * 150 * Calls the driver's \c drm_driver_irq_uninstall() function, and stops the irq. 151 */ 152 int drm_irq_uninstall(struct drm_device * dev) 153 { 154 int irq_enabled; 155 156 if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ)) 157 return -EINVAL; 158 159 mutex_lock(&dev->struct_mutex); 160 irq_enabled = dev->irq_enabled; 161 dev->irq_enabled = 0; 162 mutex_unlock(&dev->struct_mutex); 163 164 if (!irq_enabled) 165 return -EINVAL; 166 167 DRM_DEBUG("irq=%d\n", dev->irq); 168 169 dev->driver->irq_uninstall(dev); 170 171 free_irq(dev->irq, dev); 172 173 dev->locked_tasklet_func = NULL; 174 175 return 0; 176 } 177 178 EXPORT_SYMBOL(drm_irq_uninstall); 179 180 /** 181 * IRQ control ioctl. 182 * 183 * \param inode device inode. 184 * \param file_priv DRM file private. 185 * \param cmd command. 186 * \param arg user argument, pointing to a drm_control structure. 187 * \return zero on success or a negative number on failure. 188 * 189 * Calls irq_install() or irq_uninstall() according to \p arg. 190 */ 191 int drm_control(struct drm_device *dev, void *data, 192 struct drm_file *file_priv) 193 { 194 struct drm_control *ctl = data; 195 196 /* if we haven't irq we fallback for compatibility reasons - this used to be a separate function in drm_dma.h */ 197 198 199 switch (ctl->func) { 200 case DRM_INST_HANDLER: 201 if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ)) 202 return 0; 203 if (dev->if_version < DRM_IF_VERSION(1, 2) && 204 ctl->irq != dev->irq) 205 return -EINVAL; 206 return drm_irq_install(dev); 207 case DRM_UNINST_HANDLER: 208 if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ)) 209 return 0; 210 return drm_irq_uninstall(dev); 211 default: 212 return -EINVAL; 213 } 214 } 215 216 /** 217 * Wait for VBLANK. 218 * 219 * \param inode device inode. 220 * \param file_priv DRM file private. 221 * \param cmd command. 222 * \param data user argument, pointing to a drm_wait_vblank structure. 223 * \return zero on success or a negative number on failure. 224 * 225 * Verifies the IRQ is installed. 226 * 227 * If a signal is requested checks if this task has already scheduled the same signal 228 * for the same vblank sequence number - nothing to be done in 229 * that case. If the number of tasks waiting for the interrupt exceeds 100 the 230 * function fails. Otherwise adds a new entry to drm_device::vbl_sigs for this 231 * task. 232 * 233 * If a signal is not requested, then calls vblank_wait(). 234 */ 235 int drm_wait_vblank(struct drm_device *dev, void *data, struct drm_file *file_priv) 236 { 237 union drm_wait_vblank *vblwait = data; 238 struct timeval now; 239 int ret = 0; 240 unsigned int flags, seq; 241 242 if ((!dev->irq) || (!dev->irq_enabled)) 243 return -EINVAL; 244 245 if (vblwait->request.type & 246 ~(_DRM_VBLANK_TYPES_MASK | _DRM_VBLANK_FLAGS_MASK)) { 247 DRM_ERROR("Unsupported type value 0x%x, supported mask 0x%x\n", 248 vblwait->request.type, 249 (_DRM_VBLANK_TYPES_MASK | _DRM_VBLANK_FLAGS_MASK)); 250 return -EINVAL; 251 } 252 253 flags = vblwait->request.type & _DRM_VBLANK_FLAGS_MASK; 254 255 if (!drm_core_check_feature(dev, (flags & _DRM_VBLANK_SECONDARY) ? 256 DRIVER_IRQ_VBL2 : DRIVER_IRQ_VBL)) 257 return -EINVAL; 258 259 seq = atomic_read((flags & _DRM_VBLANK_SECONDARY) ? &dev->vbl_received2 260 : &dev->vbl_received); 261 262 switch (vblwait->request.type & _DRM_VBLANK_TYPES_MASK) { 263 case _DRM_VBLANK_RELATIVE: 264 vblwait->request.sequence += seq; 265 vblwait->request.type &= ~_DRM_VBLANK_RELATIVE; 266 case _DRM_VBLANK_ABSOLUTE: 267 break; 268 default: 269 return -EINVAL; 270 } 271 272 if ((flags & _DRM_VBLANK_NEXTONMISS) && 273 (seq - vblwait->request.sequence) <= (1<<23)) { 274 vblwait->request.sequence = seq + 1; 275 } 276 277 if (flags & _DRM_VBLANK_SIGNAL) { 278 unsigned long irqflags; 279 struct list_head *vbl_sigs = (flags & _DRM_VBLANK_SECONDARY) 280 ? &dev->vbl_sigs2 : &dev->vbl_sigs; 281 struct drm_vbl_sig *vbl_sig; 282 283 spin_lock_irqsave(&dev->vbl_lock, irqflags); 284 285 /* Check if this task has already scheduled the same signal 286 * for the same vblank sequence number; nothing to be done in 287 * that case 288 */ 289 list_for_each_entry(vbl_sig, vbl_sigs, head) { 290 if (vbl_sig->sequence == vblwait->request.sequence 291 && vbl_sig->info.si_signo == 292 vblwait->request.signal 293 && vbl_sig->task == current) { 294 spin_unlock_irqrestore(&dev->vbl_lock, 295 irqflags); 296 vblwait->reply.sequence = seq; 297 goto done; 298 } 299 } 300 301 if (dev->vbl_pending >= 100) { 302 spin_unlock_irqrestore(&dev->vbl_lock, irqflags); 303 return -EBUSY; 304 } 305 306 dev->vbl_pending++; 307 308 spin_unlock_irqrestore(&dev->vbl_lock, irqflags); 309 310 if (! 311 (vbl_sig = 312 drm_alloc(sizeof(struct drm_vbl_sig), DRM_MEM_DRIVER))) { 313 return -ENOMEM; 314 } 315 316 memset((void *)vbl_sig, 0, sizeof(*vbl_sig)); 317 318 vbl_sig->sequence = vblwait->request.sequence; 319 vbl_sig->info.si_signo = vblwait->request.signal; 320 vbl_sig->task = current; 321 322 spin_lock_irqsave(&dev->vbl_lock, irqflags); 323 324 list_add_tail(&vbl_sig->head, vbl_sigs); 325 326 spin_unlock_irqrestore(&dev->vbl_lock, irqflags); 327 328 vblwait->reply.sequence = seq; 329 } else { 330 if (flags & _DRM_VBLANK_SECONDARY) { 331 if (dev->driver->vblank_wait2) 332 ret = dev->driver->vblank_wait2(dev, &vblwait->request.sequence); 333 } else if (dev->driver->vblank_wait) 334 ret = 335 dev->driver->vblank_wait(dev, 336 &vblwait->request.sequence); 337 338 do_gettimeofday(&now); 339 vblwait->reply.tval_sec = now.tv_sec; 340 vblwait->reply.tval_usec = now.tv_usec; 341 } 342 343 done: 344 return ret; 345 } 346 347 /** 348 * Send the VBLANK signals. 349 * 350 * \param dev DRM device. 351 * 352 * Sends a signal for each task in drm_device::vbl_sigs and empties the list. 353 * 354 * If a signal is not requested, then calls vblank_wait(). 355 */ 356 void drm_vbl_send_signals(struct drm_device * dev) 357 { 358 unsigned long flags; 359 int i; 360 361 spin_lock_irqsave(&dev->vbl_lock, flags); 362 363 for (i = 0; i < 2; i++) { 364 struct drm_vbl_sig *vbl_sig, *tmp; 365 struct list_head *vbl_sigs = i ? &dev->vbl_sigs2 : &dev->vbl_sigs; 366 unsigned int vbl_seq = atomic_read(i ? &dev->vbl_received2 : 367 &dev->vbl_received); 368 369 list_for_each_entry_safe(vbl_sig, tmp, vbl_sigs, head) { 370 if ((vbl_seq - vbl_sig->sequence) <= (1 << 23)) { 371 vbl_sig->info.si_code = vbl_seq; 372 send_sig_info(vbl_sig->info.si_signo, 373 &vbl_sig->info, vbl_sig->task); 374 375 list_del(&vbl_sig->head); 376 377 drm_free(vbl_sig, sizeof(*vbl_sig), 378 DRM_MEM_DRIVER); 379 380 dev->vbl_pending--; 381 } 382 } 383 } 384 385 spin_unlock_irqrestore(&dev->vbl_lock, flags); 386 } 387 388 EXPORT_SYMBOL(drm_vbl_send_signals); 389 390 /** 391 * Tasklet wrapper function. 392 * 393 * \param data DRM device in disguise. 394 * 395 * Attempts to grab the HW lock and calls the driver callback on success. On 396 * failure, leave the lock marked as contended so the callback can be called 397 * from drm_unlock(). 398 */ 399 static void drm_locked_tasklet_func(unsigned long data) 400 { 401 struct drm_device *dev = (struct drm_device *)data; 402 unsigned long irqflags; 403 404 spin_lock_irqsave(&dev->tasklet_lock, irqflags); 405 406 if (!dev->locked_tasklet_func || 407 !drm_lock_take(&dev->lock, 408 DRM_KERNEL_CONTEXT)) { 409 spin_unlock_irqrestore(&dev->tasklet_lock, irqflags); 410 return; 411 } 412 413 dev->lock.lock_time = jiffies; 414 atomic_inc(&dev->counts[_DRM_STAT_LOCKS]); 415 416 dev->locked_tasklet_func(dev); 417 418 drm_lock_free(&dev->lock, 419 DRM_KERNEL_CONTEXT); 420 421 dev->locked_tasklet_func = NULL; 422 423 spin_unlock_irqrestore(&dev->tasklet_lock, irqflags); 424 } 425 426 /** 427 * Schedule a tasklet to call back a driver hook with the HW lock held. 428 * 429 * \param dev DRM device. 430 * \param func Driver callback. 431 * 432 * This is intended for triggering actions that require the HW lock from an 433 * interrupt handler. The lock will be grabbed ASAP after the interrupt handler 434 * completes. Note that the callback may be called from interrupt or process 435 * context, it must not make any assumptions about this. Also, the HW lock will 436 * be held with the kernel context or any client context. 437 */ 438 void drm_locked_tasklet(struct drm_device *dev, void (*func)(struct drm_device *)) 439 { 440 unsigned long irqflags; 441 static DECLARE_TASKLET(drm_tasklet, drm_locked_tasklet_func, 0); 442 443 if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ) || 444 test_bit(TASKLET_STATE_SCHED, &drm_tasklet.state)) 445 return; 446 447 spin_lock_irqsave(&dev->tasklet_lock, irqflags); 448 449 if (dev->locked_tasklet_func) { 450 spin_unlock_irqrestore(&dev->tasklet_lock, irqflags); 451 return; 452 } 453 454 dev->locked_tasklet_func = func; 455 456 spin_unlock_irqrestore(&dev->tasklet_lock, irqflags); 457 458 drm_tasklet.data = (unsigned long)dev; 459 460 tasklet_hi_schedule(&drm_tasklet); 461 } 462 EXPORT_SYMBOL(drm_locked_tasklet); 463