drm_irq.c revision 194965 
1/*-
2 * Copyright 2003 Eric Anholt
3 * All Rights Reserved.
4 *
5 * Permission is hereby granted, free of charge, to any person obtaining a
6 * copy of this software and associated documentation files (the "Software"),
7 * to deal in the Software without restriction, including without limitation
8 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
9 * and/or sell copies of the Software, and to permit persons to whom the
10 * Software is furnished to do so, subject to the following conditions:
11 *
12 * The above copyright notice and this permission notice (including the next
13 * paragraph) shall be included in all copies or substantial portions of the
14 * 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 * ERIC ANHOLT BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
20 * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
21 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
22 *
23 * Authors:
24 *    Eric Anholt <anholt@FreeBSD.org>
25 *
26 */
27
28#include <sys/cdefs.h>
29__FBSDID("$FreeBSD: head/sys/dev/drm/drm_irq.c 194965 2009-06-25 15:36:11Z rnoland $");
30
31/** @file drm_irq.c
32 * Support code for handling setup/teardown of interrupt handlers and
33 * handing interrupt handlers off to the drivers.
34 */
35
36#include "dev/drm/drmP.h"
37#include "dev/drm/drm.h"
38
39int drm_irq_by_busid(struct drm_device *dev, void *data,
40		     struct drm_file *file_priv)
41{
42	struct drm_irq_busid *irq = data;
43
44	if ((irq->busnum >> 8) != dev->pci_domain ||
45	    (irq->busnum & 0xff) != dev->pci_bus ||
46	    irq->devnum != dev->pci_slot ||
47	    irq->funcnum != dev->pci_func)
48		return EINVAL;
49
50	irq->irq = dev->irq;
51
52	DRM_DEBUG("%d:%d:%d => IRQ %d\n",
53	    irq->busnum, irq->devnum, irq->funcnum, irq->irq);
54
55	return 0;
56}
57
58static irqreturn_t
59drm_irq_handler_wrap(DRM_IRQ_ARGS)
60{
61	struct drm_device *dev = arg;
62
63	DRM_SPINLOCK(&dev->irq_lock);
64	dev->driver->irq_handler(arg);
65	DRM_SPINUNLOCK(&dev->irq_lock);
66}
67
68static void vblank_disable_fn(void *arg)
69{
70	struct drm_device *dev = (struct drm_device *)arg;
71	int i;
72
73	/* Make sure that we are called with the lock held */
74	mtx_assert(&dev->vbl_lock, MA_OWNED);
75
76	if (callout_pending(&dev->vblank_disable_timer)) {
77		/* callout was reset */
78		return;
79	}
80	if (!callout_active(&dev->vblank_disable_timer)) {
81		/* callout was stopped */
82		return;
83	}
84	callout_deactivate(&dev->vblank_disable_timer);
85
86	DRM_DEBUG("vblank_disable: %s\n", dev->vblank_disable_allowed ?
87		"allowed" : "denied");
88	if (!dev->vblank_disable_allowed)
89		return;
90
91	for (i = 0; i < dev->num_crtcs; i++) {
92		if (dev->vblank[i].refcount == 0 &&
93		    dev->vblank[i].enabled && !dev->vblank[i].inmodeset) {
94			DRM_DEBUG("disabling vblank on crtc %d\n", i);
95			dev->vblank[i].last =
96			    dev->driver->get_vblank_counter(dev, i);
97			dev->driver->disable_vblank(dev, i);
98			dev->vblank[i].enabled = 0;
99		}
100	}
101}
102
103void drm_vblank_cleanup(struct drm_device *dev)
104{
105	/* Bail if the driver didn't call drm_vblank_init() */
106	if (dev->num_crtcs == 0)
107		return;
108
109	DRM_SPINLOCK(&dev->vbl_lock);
110	callout_stop(&dev->vblank_disable_timer);
111	DRM_SPINUNLOCK(&dev->vbl_lock);
112
113	callout_drain(&dev->vblank_disable_timer);
114
115	DRM_SPINLOCK(&dev->vbl_lock);
116	vblank_disable_fn((void *)dev);
117	DRM_SPINUNLOCK(&dev->vbl_lock);
118
119	free(dev->vblank, DRM_MEM_DRIVER);
120
121	dev->num_crtcs = 0;
122}
123
124int drm_vblank_init(struct drm_device *dev, int num_crtcs)
125{
126	int i, ret = ENOMEM;
127
128	callout_init_mtx(&dev->vblank_disable_timer, &dev->vbl_lock, 0);
129	dev->num_crtcs = num_crtcs;
130
131	dev->vblank = malloc(sizeof(struct drm_vblank_info) * num_crtcs,
132	    DRM_MEM_DRIVER, M_NOWAIT | M_ZERO);
133	if (!dev->vblank)
134	    goto err;
135
136	DRM_DEBUG("\n");
137
138	/* Zero per-crtc vblank stuff */
139	DRM_SPINLOCK(&dev->vbl_lock);
140	for (i = 0; i < num_crtcs; i++) {
141		DRM_INIT_WAITQUEUE(&dev->vblank[i].queue);
142		dev->vblank[i].refcount = 0;
143		atomic_set_rel_32(&dev->vblank[i].count, 0);
144	}
145	dev->vblank_disable_allowed = 0;
146	DRM_SPINUNLOCK(&dev->vbl_lock);
147
148	return 0;
149
150err:
151	drm_vblank_cleanup(dev);
152	return ret;
153}
154
155int drm_irq_install(struct drm_device *dev)
156{
157	int crtc, retcode;
158
159	if (dev->irq == 0 || dev->dev_private == NULL)
160		return EINVAL;
161
162	DRM_DEBUG("irq=%d\n", dev->irq);
163
164	DRM_LOCK();
165	if (dev->irq_enabled) {
166		DRM_UNLOCK();
167		return EBUSY;
168	}
169	dev->irq_enabled = 1;
170
171	dev->context_flag = 0;
172
173	/* Before installing handler */
174	dev->driver->irq_preinstall(dev);
175	DRM_UNLOCK();
176
177	/* Install handler */
178#if __FreeBSD_version >= 700031
179	retcode = bus_setup_intr(dev->device, dev->irqr,
180				 INTR_TYPE_TTY | INTR_MPSAFE,
181				 NULL, drm_irq_handler_wrap, dev, &dev->irqh);
182#else
183	retcode = bus_setup_intr(dev->device, dev->irqr,
184				 INTR_TYPE_TTY | INTR_MPSAFE,
185				 drm_irq_handler_wrap, dev, &dev->irqh);
186#endif
187	if (retcode != 0)
188		goto err;
189
190	/* After installing handler */
191	DRM_LOCK();
192	dev->driver->irq_postinstall(dev);
193	DRM_UNLOCK();
194	if (dev->driver->enable_vblank) {
195		DRM_SPINLOCK(&dev->vbl_lock);
196		for( crtc = 0 ; crtc < dev->num_crtcs ; crtc++) {
197			if (dev->driver->enable_vblank(dev, crtc) == 0) {
198				dev->vblank[crtc].enabled = 1;
199			}
200		}
201		callout_reset(&dev->vblank_disable_timer, 5 * DRM_HZ,
202		    (timeout_t *)vblank_disable_fn, (void *)dev);
203		DRM_SPINUNLOCK(&dev->vbl_lock);
204	}
205
206	return 0;
207err:
208	DRM_LOCK();
209	dev->irq_enabled = 0;
210	DRM_UNLOCK();
211
212	return retcode;
213}
214
215int drm_irq_uninstall(struct drm_device *dev)
216{
217	int crtc;
218
219	if (!dev->irq_enabled)
220		return EINVAL;
221
222	dev->irq_enabled = 0;
223
224	/*
225	* Wake up any waiters so they don't hang.
226	*/
227	DRM_SPINLOCK(&dev->vbl_lock);
228	for (crtc = 0; crtc < dev->num_crtcs; crtc++) {
229		if (dev->vblank[crtc].enabled) {
230			DRM_WAKEUP(&dev->vblank[crtc].queue);
231			dev->vblank[crtc].last =
232			    dev->driver->get_vblank_counter(dev, crtc);
233			dev->vblank[crtc].enabled = 0;
234		}
235	}
236	DRM_SPINUNLOCK(&dev->vbl_lock);
237
238	DRM_DEBUG("irq=%d\n", dev->irq);
239
240	dev->driver->irq_uninstall(dev);
241
242	DRM_UNLOCK();
243	bus_teardown_intr(dev->device, dev->irqr, dev->irqh);
244	DRM_LOCK();
245
246	return 0;
247}
248
249int drm_control(struct drm_device *dev, void *data, struct drm_file *file_priv)
250{
251	struct drm_control *ctl = data;
252	int err;
253
254	switch (ctl->func) {
255	case DRM_INST_HANDLER:
256		/* Handle drivers whose DRM used to require IRQ setup but the
257		 * no longer does.
258		 */
259		if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ))
260			return 0;
261		if (dev->if_version < DRM_IF_VERSION(1, 2) &&
262		    ctl->irq != dev->irq)
263			return EINVAL;
264		return drm_irq_install(dev);
265	case DRM_UNINST_HANDLER:
266		if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ))
267			return 0;
268		DRM_LOCK();
269		err = drm_irq_uninstall(dev);
270		DRM_UNLOCK();
271		return err;
272	default:
273		return EINVAL;
274	}
275}
276
277u32 drm_vblank_count(struct drm_device *dev, int crtc)
278{
279	return atomic_load_acq_32(&dev->vblank[crtc].count);
280}
281
282static void drm_update_vblank_count(struct drm_device *dev, int crtc)
283{
284	u32 cur_vblank, diff;
285
286	/*
287	 * Interrupts were disabled prior to this call, so deal with counter
288	 * wrap if needed.
289	 * NOTE!  It's possible we lost a full dev->max_vblank_count events
290	 * here if the register is small or we had vblank interrupts off for
291	 * a long time.
292	 */
293	cur_vblank = dev->driver->get_vblank_counter(dev, crtc);
294	diff = cur_vblank - dev->vblank[crtc].last;
295	if (cur_vblank < dev->vblank[crtc].last) {
296		diff += dev->max_vblank_count;
297
298		DRM_DEBUG("vblank[%d].last=0x%x, cur_vblank=0x%x => diff=0x%x\n",
299		    crtc, dev->vblank[crtc].last, cur_vblank, diff);
300	}
301
302	DRM_DEBUG("enabling vblank interrupts on crtc %d, missed %d\n",
303	    crtc, diff);
304
305	atomic_add_rel_32(&dev->vblank[crtc].count, diff);
306}
307
308int drm_vblank_get(struct drm_device *dev, int crtc)
309{
310	int ret = 0;
311
312	/* Make sure that we are called with the lock held */
313	mtx_assert(&dev->vbl_lock, MA_OWNED);
314
315	/* Going from 0->1 means we have to enable interrupts again */
316	if (++dev->vblank[crtc].refcount == 1 &&
317	    !dev->vblank[crtc].enabled) {
318		ret = dev->driver->enable_vblank(dev, crtc);
319		DRM_DEBUG("enabling vblank on crtc %d, ret: %d\n", crtc, ret);
320		if (ret)
321			--dev->vblank[crtc].refcount;
322		else {
323			dev->vblank[crtc].enabled = 1;
324			drm_update_vblank_count(dev, crtc);
325		}
326	}
327
328	return ret;
329}
330
331void drm_vblank_put(struct drm_device *dev, int crtc)
332{
333	/* Make sure that we are called with the lock held */
334	mtx_assert(&dev->vbl_lock, MA_OWNED);
335
336	KASSERT(dev->vblank[crtc].refcount > 0,
337	    ("invalid refcount"));
338
339	/* Last user schedules interrupt disable */
340	if (--dev->vblank[crtc].refcount == 0)
341	    callout_reset(&dev->vblank_disable_timer, 5 * DRM_HZ,
342		(timeout_t *)vblank_disable_fn, (void *)dev);
343}
344
345int drm_modeset_ctl(struct drm_device *dev, void *data,
346		    struct drm_file *file_priv)
347{
348	struct drm_modeset_ctl *modeset = data;
349	int crtc, ret = 0;
350
351	/* If drm_vblank_init() hasn't been called yet, just no-op */
352	if (!dev->num_crtcs)
353		goto out;
354
355	crtc = modeset->crtc;
356	if (crtc >= dev->num_crtcs) {
357		ret = EINVAL;
358		goto out;
359	}
360
361	/*
362	 * To avoid all the problems that might happen if interrupts
363	 * were enabled/disabled around or between these calls, we just
364	 * have the kernel take a reference on the CRTC (just once though
365	 * to avoid corrupting the count if multiple, mismatch calls occur),
366	 * so that interrupts remain enabled in the interim.
367	 */
368	switch (modeset->cmd) {
369	case _DRM_PRE_MODESET:
370		DRM_DEBUG("pre-modeset, crtc %d\n", crtc);
371		DRM_SPINLOCK(&dev->vbl_lock);
372		if (!dev->vblank[crtc].inmodeset) {
373			dev->vblank[crtc].inmodeset = 0x1;
374			if (drm_vblank_get(dev, crtc) == 0)
375				dev->vblank[crtc].inmodeset |= 0x2;
376		}
377		DRM_SPINUNLOCK(&dev->vbl_lock);
378		break;
379	case _DRM_POST_MODESET:
380		DRM_DEBUG("post-modeset, crtc %d\n", crtc);
381		DRM_SPINLOCK(&dev->vbl_lock);
382		if (dev->vblank[crtc].inmodeset) {
383			if (dev->vblank[crtc].inmodeset & 0x2)
384				drm_vblank_put(dev, crtc);
385			dev->vblank[crtc].inmodeset = 0;
386		}
387		dev->vblank_disable_allowed = 1;
388		DRM_SPINUNLOCK(&dev->vbl_lock);
389		break;
390	default:
391		ret = EINVAL;
392		break;
393	}
394
395out:
396	return ret;
397}
398
399int drm_wait_vblank(struct drm_device *dev, void *data, struct drm_file *file_priv)
400{
401	union drm_wait_vblank *vblwait = data;
402	unsigned int flags, seq, crtc;
403	int ret = 0;
404
405	if (!dev->irq_enabled)
406		return EINVAL;
407
408	if (vblwait->request.type &
409	    ~(_DRM_VBLANK_TYPES_MASK | _DRM_VBLANK_FLAGS_MASK)) {
410		DRM_ERROR("Unsupported type value 0x%x, supported mask 0x%x\n",
411		    vblwait->request.type,
412		    (_DRM_VBLANK_TYPES_MASK | _DRM_VBLANK_FLAGS_MASK));
413		return EINVAL;
414	}
415
416	flags = vblwait->request.type & _DRM_VBLANK_FLAGS_MASK;
417	crtc = flags & _DRM_VBLANK_SECONDARY ? 1 : 0;
418
419	if (crtc >= dev->num_crtcs)
420		return EINVAL;
421
422	DRM_SPINLOCK(&dev->vbl_lock);
423	ret = drm_vblank_get(dev, crtc);
424	DRM_SPINUNLOCK(&dev->vbl_lock);
425	if (ret) {
426		DRM_ERROR("failed to acquire vblank counter, %d\n", ret);
427		return ret;
428	}
429	seq = drm_vblank_count(dev, crtc);
430
431	switch (vblwait->request.type & _DRM_VBLANK_TYPES_MASK) {
432	case _DRM_VBLANK_RELATIVE:
433		vblwait->request.sequence += seq;
434		vblwait->request.type &= ~_DRM_VBLANK_RELATIVE;
435	case _DRM_VBLANK_ABSOLUTE:
436		break;
437	default:
438		ret = EINVAL;
439		goto done;
440	}
441
442	if ((flags & _DRM_VBLANK_NEXTONMISS) &&
443	    (seq - vblwait->request.sequence) <= (1<<23)) {
444		vblwait->request.sequence = seq + 1;
445	}
446
447	if (flags & _DRM_VBLANK_SIGNAL) {
448		/* There have never been any consumers */
449		ret = EINVAL;
450	} else {
451		DRM_DEBUG("waiting on vblank count %d, crtc %d\n",
452		    vblwait->request.sequence, crtc);
453		for ( ret = 0 ; !ret && !(((drm_vblank_count(dev, crtc) -
454		    vblwait->request.sequence) <= (1 << 23)) ||
455		    !dev->irq_enabled) ; ) {
456			mtx_lock(&dev->irq_lock);
457			if (!(((drm_vblank_count(dev, crtc) -
458			    vblwait->request.sequence) <= (1 << 23)) ||
459			    !dev->irq_enabled))
460				ret = mtx_sleep(&dev->vblank[crtc].queue,
461				    &dev->irq_lock, PCATCH, "vblwtq",
462				    DRM_HZ);
463			mtx_unlock(&dev->irq_lock);
464		}
465
466		if (ret != EINTR && ret != ERESTART) {
467			struct timeval now;
468
469			microtime(&now);
470			vblwait->reply.tval_sec = now.tv_sec;
471			vblwait->reply.tval_usec = now.tv_usec;
472			vblwait->reply.sequence = drm_vblank_count(dev, crtc);
473			DRM_DEBUG("returning %d to client, irq_enabled %d\n",
474			    vblwait->reply.sequence, dev->irq_enabled);
475		} else {
476			DRM_DEBUG("vblank wait interrupted by signal\n");
477		}
478	}
479
480done:
481	DRM_SPINLOCK(&dev->vbl_lock);
482	drm_vblank_put(dev, crtc);
483	DRM_SPINUNLOCK(&dev->vbl_lock);
484
485	return ret;
486}
487
488void drm_handle_vblank(struct drm_device *dev, int crtc)
489{
490	atomic_add_rel_32(&dev->vblank[crtc].count, 1);
491	DRM_WAKEUP(&dev->vblank[crtc].queue);
492}
493
494