aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/gpu/drm/i915/i915_irq.c
blob: 82752d6177a4949d406ec383b53cc31e6bcf9474 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
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
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
/* i915_irq.c -- IRQ support for the I915 -*- linux-c -*-
 */
/*
 * Copyright 2003 Tungsten Graphics, Inc., Cedar Park, Texas.
 * 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 TUNGSTEN 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 "drm.h"
#include "i915_drm.h"
#include "i915_drv.h"

#define MAX_NOPID ((u32)~0)

/** These are the interrupts used by the driver */
#define I915_INTERRUPT_ENABLE_MASK (I915_USER_INTERRUPT |		\
				    I915_ASLE_INTERRUPT |		\
				    I915_DISPLAY_PIPE_A_EVENT_INTERRUPT | \
				    I915_DISPLAY_PIPE_B_EVENT_INTERRUPT)

void
i915_enable_irq(drm_i915_private_t *dev_priv, u32 mask)
{
	if ((dev_priv->irq_mask_reg & mask) != 0) {
		dev_priv->irq_mask_reg &= ~mask;
		I915_WRITE(IMR, dev_priv->irq_mask_reg);
		(void) I915_READ(IMR);
	}
}

static inline void
i915_disable_irq(drm_i915_private_t *dev_priv, u32 mask)
{
	if ((dev_priv->irq_mask_reg & mask) != mask) {
		dev_priv->irq_mask_reg |= mask;
		I915_WRITE(IMR, dev_priv->irq_mask_reg);
		(void) I915_READ(IMR);
	}
}

/**
 * i915_pipe_enabled - check if a pipe is enabled
 * @dev: DRM device
 * @pipe: pipe to check
 *
 * Reading certain registers when the pipe is disabled can hang the chip.
 * Use this routine to make sure the PLL is running and the pipe is active
 * before reading such registers if unsure.
 */
static int
i915_pipe_enabled(struct drm_device *dev, int pipe)
{
	drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
	unsigned long pipeconf = pipe ? PIPEBCONF : PIPEACONF;

	if (I915_READ(pipeconf) & PIPEACONF_ENABLE)
		return 1;

	return 0;
}

/* Called from drm generic code, passed a 'crtc', which
 * we use as a pipe index
 */
u32 i915_get_vblank_counter(struct drm_device *dev, int pipe)
{
	drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
	unsigned long high_frame;
	unsigned long low_frame;
	u32 high1, high2, low, count;

	high_frame = pipe ? PIPEBFRAMEHIGH : PIPEAFRAMEHIGH;
	low_frame = pipe ? PIPEBFRAMEPIXEL : PIPEAFRAMEPIXEL;

	if (!i915_pipe_enabled(dev, pipe)) {
		DRM_ERROR("trying to get vblank count for disabled pipe %d\n", pipe);
		return 0;
	}

	/*
	 * High & low register fields aren't synchronized, so make sure
	 * we get a low value that's stable across two reads of the high
	 * register.
	 */
	do {
		high1 = ((I915_READ(high_frame) & PIPE_FRAME_HIGH_MASK) >>
			 PIPE_FRAME_HIGH_SHIFT);
		low =  ((I915_READ(low_frame) & PIPE_FRAME_LOW_MASK) >>
			PIPE_FRAME_LOW_SHIFT);
		high2 = ((I915_READ(high_frame) & PIPE_FRAME_HIGH_MASK) >>
			 PIPE_FRAME_HIGH_SHIFT);
	} while (high1 != high2);

	count = (high1 << 8) | low;

	return count;
}

irqreturn_t i915_driver_irq_handler(DRM_IRQ_ARGS)
{
	struct drm_device *dev = (struct drm_device *) arg;
	drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
	u32 iir;
	u32 pipea_stats, pipeb_stats;
	int vblank = 0;

	atomic_inc(&dev_priv->irq_received);

	if (dev->pdev->msi_enabled)
		I915_WRITE(IMR, ~0);
	iir = I915_READ(IIR);

	if (iir == 0) {
		if (dev->pdev->msi_enabled) {
			I915_WRITE(IMR, dev_priv->irq_mask_reg);
			(void) I915_READ(IMR);
		}
		return IRQ_NONE;
	}

	/*
	 * Clear the PIPE(A|B)STAT regs before the IIR otherwise
	 * we may get extra interrupts.
	 */
	if (iir & I915_DISPLAY_PIPE_A_EVENT_INTERRUPT) {
		pipea_stats = I915_READ(PIPEASTAT);
		if (!(dev_priv->vblank_pipe & DRM_I915_VBLANK_PIPE_A))
			pipea_stats &= ~(PIPE_START_VBLANK_INTERRUPT_ENABLE |
					 PIPE_VBLANK_INTERRUPT_ENABLE);
		else if (pipea_stats & (PIPE_START_VBLANK_INTERRUPT_STATUS|
					PIPE_VBLANK_INTERRUPT_STATUS)) {
			vblank++;
			drm_handle_vblank(dev, 0);
		}

		I915_WRITE(PIPEASTAT, pipea_stats);
	}
	if (iir & I915_DISPLAY_PIPE_B_EVENT_INTERRUPT) {
		pipeb_stats = I915_READ(PIPEBSTAT);
		/* Ack the event */
		I915_WRITE(PIPEBSTAT, pipeb_stats);

		/* The vblank interrupt gets enabled even if we didn't ask for
		   it, so make sure it's shut down again */
		if (!(dev_priv->vblank_pipe & DRM_I915_VBLANK_PIPE_B))
			pipeb_stats &= ~(PIPE_START_VBLANK_INTERRUPT_ENABLE |
					 PIPE_VBLANK_INTERRUPT_ENABLE);
		else if (pipeb_stats & (PIPE_START_VBLANK_INTERRUPT_STATUS|
					PIPE_VBLANK_INTERRUPT_STATUS)) {
			vblank++;
			drm_handle_vblank(dev, 1);
		}

		if (pipeb_stats & I915_LEGACY_BLC_EVENT_STATUS)
			opregion_asle_intr(dev);
		I915_WRITE(PIPEBSTAT, pipeb_stats);
	}

	I915_WRITE(IIR, iir);
	if (dev->pdev->msi_enabled)
		I915_WRITE(IMR, dev_priv->irq_mask_reg);
	(void) I915_READ(IIR); /* Flush posted writes */

	if (dev_priv->sarea_priv)
		dev_priv->sarea_priv->last_dispatch =
			READ_BREADCRUMB(dev_priv);

	if (iir & I915_USER_INTERRUPT) {
		dev_priv->mm.irq_gem_seqno = i915_get_gem_seqno(dev);
		DRM_WAKEUP(&dev_priv->irq_queue);
	}

	if (iir & I915_ASLE_INTERRUPT)
		opregion_asle_intr(dev);

	return IRQ_HANDLED;
}

static int i915_emit_irq(struct drm_device * dev)
{
	drm_i915_private_t *dev_priv = dev->dev_private;
	RING_LOCALS;

	i915_kernel_lost_context(dev);

	DRM_DEBUG("\n");

	dev_priv->counter++;
	if (dev_priv->counter > 0x7FFFFFFFUL)
		dev_priv->counter = 1;
	if (dev_priv->sarea_priv)
		dev_priv->sarea_priv->last_enqueue = dev_priv->counter;

	BEGIN_LP_RING(4);
	OUT_RING(MI_STORE_DWORD_INDEX);
	OUT_RING(I915_BREADCRUMB_INDEX << MI_STORE_DWORD_INDEX_SHIFT);
	OUT_RING(dev_priv->counter);
	OUT_RING(MI_USER_INTERRUPT);
	ADVANCE_LP_RING();

	return dev_priv->counter;
}

void i915_user_irq_get(struct drm_device *dev)
{
	drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
	unsigned long irqflags;

	spin_lock_irqsave(&dev_priv->user_irq_lock, irqflags);
	if (dev->irq_enabled && (++dev_priv->user_irq_refcount == 1))
		i915_enable_irq(dev_priv, I915_USER_INTERRUPT);
	spin_unlock_irqrestore(&dev_priv->user_irq_lock, irqflags);
}

void i915_user_irq_put(struct drm_device *dev)
{
	drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
	unsigned long irqflags;

	spin_lock_irqsave(&dev_priv->user_irq_lock, irqflags);
	BUG_ON(dev->irq_enabled && dev_priv->user_irq_refcount <= 0);
	if (dev->irq_enabled && (--dev_priv->user_irq_refcount == 0))
		i915_disable_irq(dev_priv, I915_USER_INTERRUPT);
	spin_unlock_irqrestore(&dev_priv->user_irq_lock, irqflags);
}

static int i915_wait_irq(struct drm_device * dev, int irq_nr)
{
	drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
	int ret = 0;

	DRM_DEBUG("irq_nr=%d breadcrumb=%d\n", irq_nr,
		  READ_BREADCRUMB(dev_priv));

	if (READ_BREADCRUMB(dev_priv) >= irq_nr) {
		if (dev_priv->sarea_priv) {
			dev_priv->sarea_priv->last_dispatch =
				READ_BREADCRUMB(dev_priv);
		}
		return 0;
	}

	if (dev_priv->sarea_priv)
		dev_priv->sarea_priv->perf_boxes |= I915_BOX_WAIT;

	i915_user_irq_get(dev);
	DRM_WAIT_ON(ret, dev_priv->irq_queue, 3 * DRM_HZ,
		    READ_BREADCRUMB(dev_priv) >= irq_nr);
	i915_user_irq_put(dev);

	if (ret == -EBUSY) {
		DRM_ERROR("EBUSY -- rec: %d emitted: %d\n",
			  READ_BREADCRUMB(dev_priv), (int)dev_priv->counter);
	}

	if (dev_priv->sarea_priv)
		dev_priv->sarea_priv->last_dispatch =
			READ_BREADCRUMB(dev_priv);

	return ret;
}

/* Needs the lock as it touches the ring.
 */
int i915_irq_emit(struct drm_device *dev, void *data,
			 struct drm_file *file_priv)
{
	drm_i915_private_t *dev_priv = dev->dev_private;
	drm_i915_irq_emit_t *emit = data;
	int result;

	RING_LOCK_TEST_WITH_RETURN(dev, file_priv);

	if (!dev_priv) {
		DRM_ERROR("called with no initialization\n");
		return -EINVAL;
	}
	mutex_lock(&dev->struct_mutex);
	result = i915_emit_irq(dev);
	mutex_unlock(&dev->struct_mutex);

	if (DRM_COPY_TO_USER(emit->irq_seq, &result, sizeof(int))) {
		DRM_ERROR("copy_to_user\n");
		return -EFAULT;
	}

	return 0;
}

/* Doesn't need the hardware lock.
 */
int i915_irq_wait(struct drm_device *dev, void *data,
			 struct drm_file *file_priv)
{
	drm_i915_private_t *dev_priv = dev->dev_private;
	drm_i915_irq_wait_t *irqwait = data;

	if (!dev_priv) {
		DRM_ERROR("called with no initialization\n");
		return -EINVAL;
	}

	return i915_wait_irq(dev, irqwait->irq_seq);
}

/* Called from drm generic code, passed 'crtc' which
 * we use as a pipe index
 */
int i915_enable_vblank(struct drm_device *dev, int pipe)
{
	drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
	u32	pipestat_reg = 0;
	u32	pipestat;
	u32	interrupt = 0;
	unsigned long irqflags;

	switch (pipe) {
	case 0:
		pipestat_reg = PIPEASTAT;
		interrupt = I915_DISPLAY_PIPE_A_EVENT_INTERRUPT;
		break;
	case 1:
		pipestat_reg = PIPEBSTAT;
		interrupt = I915_DISPLAY_PIPE_B_EVENT_INTERRUPT;
		break;
	default:
		DRM_ERROR("tried to enable vblank on non-existent pipe %d\n",
			  pipe);
		return 0;
	}

	spin_lock_irqsave(&dev_priv->user_irq_lock, irqflags);
	/* Enabling vblank events in IMR comes before PIPESTAT write, or
	 * there's a race where the PIPESTAT vblank bit gets set to 1, so
	 * the OR of enabled PIPESTAT bits goes to 1, so the PIPExEVENT in
	 * ISR flashes to 1, but the IIR bit doesn't get set to 1 because
	 * IMR masks it.  It doesn't ever get set after we clear the masking
	 * in IMR because the ISR bit is edge, not level-triggered, on the
	 * OR of PIPESTAT bits.
	 */
	i915_enable_irq(dev_priv, interrupt);
	pipestat = I915_READ(pipestat_reg);
	if (IS_I965G(dev))
		pipestat |= PIPE_START_VBLANK_INTERRUPT_ENABLE;
	else
		pipestat |= PIPE_VBLANK_INTERRUPT_ENABLE;
	/* Clear any stale interrupt status */
	pipestat |= (PIPE_START_VBLANK_INTERRUPT_STATUS |
		     PIPE_VBLANK_INTERRUPT_STATUS);
	I915_WRITE(pipestat_reg, pipestat);
	(void) I915_READ(pipestat_reg);	/* Posting read */
	spin_unlock_irqrestore(&dev_priv->user_irq_lock, irqflags);

	return 0;
}

/* Called from drm generic code, passed 'crtc' which
 * we use as a pipe index
 */
void i915_disable_vblank(struct drm_device *dev, int pipe)
{
	drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
	u32	pipestat_reg = 0;
	u32	pipestat;
	u32	interrupt = 0;
	unsigned long irqflags;

	switch (pipe) {
	case 0:
		pipestat_reg = PIPEASTAT;
		interrupt = I915_DISPLAY_PIPE_A_EVENT_INTERRUPT;
		break;
	case 1:
		pipestat_reg = PIPEBSTAT;
		interrupt = I915_DISPLAY_PIPE_B_EVENT_INTERRUPT;
		break;
	default:
		DRM_ERROR("tried to disable vblank on non-existent pipe %d\n",
			  pipe);
		return;
		break;
	}

	spin_lock_irqsave(&dev_priv->user_irq_lock, irqflags);
	i915_disable_irq(dev_priv, interrupt);
	pipestat = I915_READ(pipestat_reg);
	pipestat &= ~(PIPE_START_VBLANK_INTERRUPT_ENABLE |
		      PIPE_VBLANK_INTERRUPT_ENABLE);
	/* Clear any stale interrupt status */
	pipestat |= (PIPE_START_VBLANK_INTERRUPT_STATUS |
		     PIPE_VBLANK_INTERRUPT_STATUS);
	I915_WRITE(pipestat_reg, pipestat);
	(void) I915_READ(pipestat_reg);	/* Posting read */
	spin_unlock_irqrestore(&dev_priv->user_irq_lock, irqflags);
}

/* Set the vblank monitor pipe
 */
int i915_vblank_pipe_set(struct drm_device *dev, void *data,
			 struct drm_file *file_priv)
{
	drm_i915_private_t *dev_priv = dev->dev_private;

	if (!dev_priv) {
		DRM_ERROR("called with no initialization\n");
		return -EINVAL;
	}

	return 0;
}

int i915_vblank_pipe_get(struct drm_device *dev, void *data,
			 struct drm_file *file_priv)
{
	drm_i915_private_t *dev_priv = dev->dev_private;
	drm_i915_vblank_pipe_t *pipe = data;

	if (!dev_priv) {
		DRM_ERROR("called with no initialization\n");
		return -EINVAL;
	}

	pipe->pipe = DRM_I915_VBLANK_PIPE_A | DRM_I915_VBLANK_PIPE_B;

	return 0;
}

/**
 * Schedule buffer swap at given vertical blank.
 */
int i915_vblank_swap(struct drm_device *dev, void *data,
		     struct drm_file *file_priv)
{
	/* The delayed swap mechanism was fundamentally racy, and has been
	 * removed.  The model was that the client requested a delayed flip/swap
	 * from the kernel, then waited for vblank before continuing to perform
	 * rendering.  The problem was that the kernel might wake the client
	 * up before it dispatched the vblank swap (since the lock has to be
	 * held while touching the ringbuffer), in which case the client would
	 * clear and start the next frame before the swap occurred, and
	 * flicker would occur in addition to likely missing the vblank.
	 *
	 * In the absence of this ioctl, userland falls back to a correct path
	 * of waiting for a vblank, then dispatching the swap on its own.
	 * Context switching to userland and back is plenty fast enough for
	 * meeting the requirements of vblank swapping.
	 */
	return -EINVAL;
}

/* drm_dma.h hooks
*/
void i915_driver_irq_preinstall(struct drm_device * dev)
{
	drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;

	I915_WRITE(HWSTAM, 0xeffe);
	I915_WRITE(IMR, 0xffffffff);
	I915_WRITE(IER, 0x0);
}

int i915_driver_irq_postinstall(struct drm_device *dev)
{
	drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
	int ret, num_pipes = 2;

	/* Set initial unmasked IRQs to just the selected vblank pipes. */
	dev_priv->irq_mask_reg = ~0;

	ret = drm_vblank_init(dev, num_pipes);
	if (ret)
		return ret;

	dev_priv->vblank_pipe = DRM_I915_VBLANK_PIPE_A | DRM_I915_VBLANK_PIPE_B;
	dev_priv->irq_mask_reg &= ~I915_DISPLAY_PIPE_A_VBLANK_INTERRUPT;
	dev_priv->irq_mask_reg &= ~I915_DISPLAY_PIPE_B_VBLANK_INTERRUPT;

	dev->max_vblank_count = 0xffffff; /* only 24 bits of frame count */

	dev_priv->irq_mask_reg &= I915_INTERRUPT_ENABLE_MASK;

	I915_WRITE(IMR, dev_priv->irq_mask_reg);
	I915_WRITE(IER, I915_INTERRUPT_ENABLE_MASK);
	(void) I915_READ(IER);

	opregion_enable_asle(dev);
	DRM_INIT_WAITQUEUE(&dev_priv->irq_queue);

	return 0;
}

void i915_driver_irq_uninstall(struct drm_device * dev)
{
	drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
	u32 temp;

	if (!dev_priv)
		return;

	dev_priv->vblank_pipe = 0;

	I915_WRITE(HWSTAM, 0xffffffff);
	I915_WRITE(IMR, 0xffffffff);
	I915_WRITE(IER, 0x0);

	temp = I915_READ(PIPEASTAT);
	I915_WRITE(PIPEASTAT, temp);
	temp = I915_READ(PIPEBSTAT);
	I915_WRITE(PIPEBSTAT, temp);
	temp = I915_READ(IIR);
	I915_WRITE(IIR, temp);
}