/* * Copyright 1998-2003 VIA Technologies, Inc. All Rights Reserved. * Copyright 2001-2003 S3 Graphics, Inc. All Rights Reserved. * * Permission is hereby granted, free of charge, to any person obtaining a * copy of this software and associated documentation files (the "Software"), * to deal in the Software without restriction, including without limitation * the rights to use, copy, modify, merge, publish, distribute, sub license, * and/or sell copies of the Software, and to permit persons to whom the * Software is furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice (including the * next paragraph) shall be included in all copies or substantial portions * of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL * VIA, S3 GRAPHICS, AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER * DEALINGS IN THE SOFTWARE. */ #include "drmP.h" #include "via_drm.h" #include "via_drv.h" #include "drm_pciids.h" static int dri_library_name(struct drm_device * dev, char * buf) { return snprintf(buf, PAGE_SIZE, "unichrome\n"); } static struct pci_device_id pciidlist[] = { viadrv_PCI_IDS }; #ifdef VIA_HAVE_FENCE static drm_fence_driver_t via_fence_driver = { .num_classes = 1, .wrap_diff = (1 << 30), .flush_diff = (1 << 20), .sequence_mask = 0xffffffffU, .lazy_capable = 1, .emit = via_fence_emit_sequence, .poke_flush = via_poke_flush, .has_irq = via_fence_has_irq, }; #endif #ifdef VIA_HAVE_BUFFER /** * If there's no thrashing. This is the preferred memory type order. */ static uint32_t via_mem_prios[] = {DRM_BO_MEM_PRIV0, DRM_BO_MEM_VRAM, DRM_BO_MEM_TT, DRM_BO_MEM_LOCAL}; /** * If we have thrashing, most memory will be evicted to TT anyway, so we might as well * just move the new buffer into TT from the start. */ static uint32_t via_busy_prios[] = {DRM_BO_MEM_TT, DRM_BO_MEM_PRIV0, DRM_BO_MEM_VRAM, DRM_BO_MEM_LOCAL}; static drm_bo_driver_t via_bo_driver = { .mem_type_prio = via_mem_prios, .mem_busy_prio = via_busy_prios, .num_mem_type_prio = ARRAY_SIZE(via_mem_prios), .num_mem_busy_prio = ARRAY_SIZE(via_busy_prios), .create_ttm_backend_entry = via_create_ttm_backend_entry, .fence_type = via_fence_types, .invalidate_caches = via_invalidate_caches, .init_mem_type = via_init_mem_type, .evict_mask = via_evict_mask, .move = NULL, }; #endif static int probe(struct pci_dev *pdev, const struct pci_device_id *ent); static struct drm_driver driver = { .driver_features = DRIVER_USE_AGP | DRIVER_USE_MTRR | DRIVER_HAVE_IRQ | DRIVER_IRQ_SHARED | DRIVER_IRQ_VBL, .load = via_driver_load, .unload = via_driver_unload, #ifndef VIA_HAVE_CORE_MM .context_ctor = via_init_context, #endif ../shared-core/mga_drv.h
generated by cgit v1.2.3 (git 2.25.1) at 2025-12-06 13:17:29 +0000
#ifdef VIA_HAVE_CORE_MM .reclaim_buffers_idlelocked = via_reclaim_buffers_locked, .lastclose = via_lastclose, #endif .get_map_ofs = drm_core_get_map_ofs, .get_reg_ofs = drm_core_get_reg_ofs, .ioctls = via_ioctls, .fops = { .owner = THIS_MODULE, .open = drm_open, .release = drm_release, .ioctl = drm_ioctl, .mmap = drm_mmap, .poll = drm_poll, .fasync = drm_fasync, }, .pci_driver = { .name = DRIVER_NAME, .id_table = pciidlist, .probe = probe, .remove = __devexit_p(drm_cleanup_pci), }, #ifdef VIA_HAVE_FENCE .fence_driver = &via_fence_driver, #endif #ifdef VIA_HAVE_BUFFER .bo_driver = &via_bo_driver, #endif .name = DRIVER_NAME, .desc = DRIVER_DESC, .date = VIA_DRM_DRIVER_DATE, .major = VIA_DRM_DRIVER_MAJOR, .minor = VIA_DRM_DRIVER_MINOR, .patchlevel = VIA_DRM_DRIVER_PATCHLEVEL }; static int probe(struct pci_dev *pdev, const struct pci_device_id *ent) { return drm_get_dev(pdev, ent, &driver); } static int __init via_init(void) { driver.num_ioctls = via_max_ioctl; via_init_command_verifier(); return drm_init(&driver, pciidlist); } static void __exit via_exit(void) { drm_exit(&driver); } module_init(via_init); module_exit(via_exit); MODULE_AUTHOR(DRIVER_AUTHOR); MODULE_DESCRIPTION(DRIVER_DESC); MODULE_LICENSE("GPL and additional rights"); d='n59' href='#n59'>59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 
/**
 * \file drm_lock.c
 * IOCTLs for locking
 *
 * \author Rickard E. (Rik) Faith <faith@valinux.com>
 * \author Gareth Hughes <gareth@valinux.com>
 */

/*
 * Created: Tue Feb  2 08:37:54 1999 by faith@valinux.com
 *
 * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas.
 * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
 * All Rights Reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice (including the next
 * paragraph) shall be included in all copies or substantial portions of the
 * Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 * OTHER DEALINGS IN THE SOFTWARE.
 */

#include "drmP.h"

static int drm_notifier(void *priv);

/**
 * Lock ioctl.
 *
 * \param inode device inode.
 * \param file_priv DRM file private.
 * \param cmd command.
 * \param arg user argument, pointing to a drm_lock structure.
 * \return zero on success or negative number on failure.
 *
 * Add the current task to the lock wait queue, and attempt to take to lock.
 */
int drm_lock(struct drm_device *dev, void *data, struct drm_file *file_priv)
{
	DECLARE_WAITQUEUE(entry, current);
	struct drm_lock *lock = data;
	struct drm_master *master = file_priv->master;
	int ret = 0;

	++file_priv->lock_count;

	if (lock->context == DRM_KERNEL_CONTEXT) {
		DRM_ERROR("Process %d using kernel context %d\n",
			  current->pid, lock->context);
		return -EINVAL;
	}

	DRM_DEBUG("%d (pid %d) requests lock (0x%08x), flags = 0x%08x\n",
		  lock->context, current->pid,
		  master->lock.hw_lock->lock, lock->flags);

	if (drm_core_check_feature(dev, DRIVER_DMA_QUEUE))
		if (lock->context < 0)
			return -EINVAL;

	add_wait_queue(&master->lock.lock_queue, &entry);
	spin_lock_bh(&master->lock.spinlock);
	master->lock.user_waiters++;
	spin_unlock_bh(&master->lock.spinlock);

	for (;;) {
		__set_current_state(TASK_INTERRUPTIBLE);
		if (!master->lock.hw_lock) {
			/* Device has been unregistered */
			ret = -EINTR;
			break;
		}
		if (drm_lock_take(&master->lock, lock->context)) {
			master->lock.file_priv = file_priv;
			master->lock.lock_time = jiffies;
			atomic_inc(&dev->counts[_DRM_STAT_LOCKS]);
			break;	/* Got lock */
		}

		/* Contention */
		schedule();
		if (signal_pending(current)) {
			ret = -ERESTARTSYS;
			break;
		}
	}
	spin_lock_bh(&master->lock.spinlock);
	master->lock.user_waiters--;
	spin_unlock_bh(&master->lock.spinlock);
	__set_current_state(TASK_RUNNING);
	remove_wait_queue(&master->lock.lock_queue, &entry);

	DRM_DEBUG("%d %s\n", lock->context,
		  ret ? "interrupted" : "has lock");
	if (ret) return ret;

	/* don't set the block all signals on the master process for now 
	 * really probably not the correct answer but lets us debug xkb
 	 * xserver for now */
	if (!file_priv->is_master) {
		sigemptyset(&dev->sigmask);
		sigaddset(&dev->sigmask, SIGSTOP);
		sigaddset(&dev->sigmask, SIGTSTP);
		sigaddset(&dev->sigmask, SIGTTIN);
		sigaddset(&dev->sigmask, SIGTTOU);
		dev->sigdata.context = lock->context;
		dev->sigdata.lock = master->lock.hw_lock;
		block_all_signals(drm_notifier, &dev->sigdata, &dev->sigmask);
	}

	if (dev->driver->dma_ready && (lock->flags & _DRM_LOCK_READY))
		dev->driver->dma_ready(dev);

	if (dev->driver->dma_quiescent && (lock->flags & _DRM_LOCK_QUIESCENT))
	{
		if (dev->driver->dma_quiescent(dev)) {
			DRM_DEBUG("%d waiting for DMA quiescent\n",
				  lock->context);
			return -EBUSY;
		}
	}

	if (dev->driver->kernel_context_switch &&
	    dev->last_context != lock->context) {
		dev->driver->kernel_context_switch(dev, dev->last_context,
						   lock->context);
	}

	return 0;
}

/**
 * Unlock ioctl.
 *
 * \param inode device inode.
 * \param file_priv DRM file private.
 * \param cmd command.
 * \param arg user argument, pointing to a drm_lock structure.
 * \return zero on success or negative number on failure.
 *
 * Transfer and free the lock.
 */
int drm_unlock(struct drm_device *dev, void *data, struct drm_file *file_priv)
{
	struct drm_lock *lock = data;
	struct drm_master *master = file_priv->master;
	unsigned long irqflags;

	if (lock->context == DRM_KERNEL_CONTEXT) {
		DRM_ERROR("Process %d using kernel context %d\n",
			  current->pid, lock->context);
		return -EINVAL;
	}

	spin_lock_irqsave(&dev->tasklet_lock, irqflags);

	if (dev->locked_tasklet_func) {
		dev->locked_tasklet_func(dev);

		dev->locked_tasklet_func = NULL;
	}

	spin_unlock_irqrestore(&dev->tasklet_lock, irqflags);

	atomic_inc(&dev->counts[_DRM_STAT_UNLOCKS]);

	/* kernel_context_switch isn't used by any of the x86 drm
	 * modules but is required by the Sparc driver.
	 */
	if (dev->driver->kernel_context_switch_unlock)
		dev->driver->kernel_context_switch_unlock(dev);
	else {
		if (drm_lock_free(&master->lock,lock->context)) {
			/* FIXME: Should really bail out here. */
		}
	}

	unblock_all_signals();
	return 0;
}

/**
 * Take the heavyweight lock.
 *
 * \param lock lock pointer.
 * \param context locking context.
 * \return one if the lock is held, or zero otherwise.
 *
 * Attempt to mark the lock as held by the given context, via the \p cmpxchg instruction.
 */
int drm_lock_take(struct drm_lock_data *lock_data,
		  unsigned int context)
{
	unsigned int old, new, prev;
	volatile unsigned int *lock = &lock_data->hw_lock->lock;

	spin_lock_bh(&lock_data->spinlock);
	do {
		old = *lock;
		if (old & _DRM_LOCK_HELD)
			new = old | _DRM_LOCK_CONT;
		else {
			new = context | _DRM_LOCK_HELD |
				((lock_data->user_waiters + lock_data->kernel_waiters > 1) ?
				 _DRM_LOCK_CONT : 0);
		}
		prev = cmpxchg(lock, old, new);
	} while (prev != old);
	spin_unlock_bh(&lock_data->spinlock);

	if (_DRM_LOCKING_CONTEXT(old) == context) {
		if (old & _DRM_LOCK_HELD) {
			if (context != DRM_KERNEL_CONTEXT) {
				DRM_ERROR("%d holds heavyweight lock\n",
					  context);
			}
			return 0;
		}
	}

	if ((_DRM_LOCKING_CONTEXT(new)) == context && (new & _DRM_LOCK_HELD)) {
		/* Have lock */

		return 1;
	}
	return 0;
}

/**
 * This takes a lock forcibly and hands it to context.	Should ONLY be used
 * inside *_unlock to give lock to kernel before calling *_dma_schedule.
 *
 * \param dev DRM device.
 * \param lock lock pointer.
 * \param context locking context.
 * \return always one.
 *
 * Resets the lock file pointer.
 * Marks the lock as held by the given context, via the \p cmpxchg instruction.
 */
static int drm_lock_transfer(struct drm_lock_data *lock_data,
			     unsigned int context)
{
	unsigned int old, new, prev;
	volatile unsigned int *lock = &lock_data->hw_lock->lock;

	lock_data->file_priv = NULL;
	do {
		old = *lock;
		new = context | _DRM_LOCK_HELD;
		prev = cmpxchg(lock, old, new);
	} while (prev != old);
	return 1;
}

/**
 * Free lock.
 *
 * \param dev DRM device.
 * \param lock lock.
 * \param context context.
 *
 * Resets the lock file pointer.
 * Marks the lock as not held, via the \p cmpxchg instruction. Wakes any task
 * waiting on the lock queue.
 */
int drm_lock_free(struct drm_lock_data *lock_data, unsigned int context)
{
	unsigned int old, new, prev;
	volatile unsigned int *lock = &lock_data->hw_lock->lock;

	spin_lock_bh(&lock_data->spinlock);
	if (lock_data->kernel_waiters != 0) {
		drm_lock_transfer(lock_data, 0);
		lock_data->idle_has_lock = 1;
		spin_unlock_bh(&lock_data->spinlock);
		return 1;
	}
	spin_unlock_bh(&lock_data->spinlock);

	do {
		old = *lock;
		new = _DRM_LOCKING_CONTEXT(old);
		prev = cmpxchg(lock, old, new);
	} while (prev != old);

	if (_DRM_LOCK_IS_HELD(old) && _DRM_LOCKING_CONTEXT(old) != context) {
		DRM_ERROR("%d freed heavyweight lock held by %d\n",
			  context, _DRM_LOCKING_CONTEXT(old));
		return 1;
	}
	wake_up_interruptible(&lock_data->lock_queue);
	return 0;
}

/**
 * If we get here, it means that the process has called DRM_IOCTL_LOCK
 * without calling DRM_IOCTL_UNLOCK.
 *
 * If the lock is not held, then let the signal proceed as usual.  If the lock
 * is held, then set the contended flag and keep the signal blocked.
 *
 * \param priv pointer to a drm_sigdata structure.
 * \return one if the signal should be delivered normally, or zero if the
 * signal should be blocked.
 */
static int drm_notifier(void *priv)
{
	struct drm_sigdata *s = (struct drm_sigdata *) priv;
	unsigned int old, new, prev;

	/* Allow signal delivery if lock isn't held */
	if (!s->lock || !_DRM_LOCK_IS_HELD(s->lock->lock)
	    || _DRM_LOCKING_CONTEXT(s->lock->lock) != s->context)
		return 1;

	/* Otherwise, set flag to force call to
	   drmUnlock */
	do {
		old = s->lock->lock;
		new = old | _DRM_LOCK_CONT;
		prev = cmpxchg(&s->lock->lock, old, new);
	} while (prev != old);
	return 0;
}

/**
 * This function returns immediately and takes the hw lock
 * with the kernel context if it is free, otherwise it gets the highest priority when and if
 * it is eventually released.
 *
 * This guarantees that the kernel will _eventually_ have the lock _unless_ it is held
 * by a blocked process. (In the latter case an explicit wait for the hardware lock would cause
 * a deadlock, which is why the "idlelock" was invented).
 *
 * This should be sufficient to wait for GPU idle without
 * having to worry about starvation.
 */

void drm_idlelock_take(struct drm_lock_data *lock_data)
{
	int ret = 0;

	spin_lock_bh(&lock_data->spinlock);
	lock_data->kernel_waiters++;
	if (!lock_data->idle_has_lock) {

		spin_unlock_bh(&lock_data->spinlock);
		ret = drm_lock_take(lock_data, DRM_KERNEL_CONTEXT);
		spin_lock_bh(&lock_data->spinlock);

		if (ret == 1)
			lock_data->idle_has_lock = 1;
	}
	spin_unlock_bh(&lock_data->spinlock);
}
EXPORT_SYMBOL(drm_idlelock_take);

void drm_idlelock_release(struct drm_lock_data *lock_data)
{
	unsigned int old, prev;
	volatile unsigned int *lock = &lock_data->hw_lock->lock;

	spin_lock_bh(&lock_data->spinlock);
	if (--lock_data->kernel_waiters == 0) {
		if (lock_data->idle_has_lock) {
			do {
				old = *lock;
				prev = cmpxchg(lock, old, DRM_KERNEL_CONTEXT);
			} while (prev != old);
			wake_up_interruptible(&lock_data->lock_queue);
			lock_data->idle_has_lock = 0;
		}
	}
	spin_unlock_bh(&lock_data->spinlock);
}
EXPORT_SYMBOL(drm_idlelock_release);

int drm_i_have_hw_lock(struct drm_device *dev, struct drm_file *file_priv)
{
	struct drm_master *master = file_priv->master;
	return (file_priv->lock_count && master->lock.hw_lock &&
		_DRM_LOCK_IS_HELD(master->lock.hw_lock->lock) &&
		master->lock.file_priv == file_priv);
}

EXPORT_SYMBOL(drm_i_have_hw_lock);