1 /*
2  * Copyright 2008 Advanced Micro Devices, Inc.
3  * Copyright 2008 Red Hat Inc.
4  * Copyright 2009 Jerome Glisse.
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a
7  * copy of this software and associated documentation files (the "Software"),
8  * to deal in the Software without restriction, including without limitation
9  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
10  * and/or sell copies of the Software, and to permit persons to whom the
11  * Software is furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be included in
14  * all copies or substantial portions of the 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  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
20  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
21  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
22  * OTHER DEALINGS IN THE SOFTWARE.
23  *
24  * Authors: Dave Airlie
25  *          Alex Deucher
26  *          Jerome Glisse
27  */
28 
29 /**
30  * DOC: Interrupt Handling
31  *
32  * Interrupts generated within GPU hardware raise interrupt requests that are
33  * passed to amdgpu IRQ handler which is responsible for detecting source and
34  * type of the interrupt and dispatching matching handlers. If handling an
35  * interrupt requires calling kernel functions that may sleep processing is
36  * dispatched to work handlers.
37  *
38  * If MSI functionality is not disabled by module parameter then MSI
39  * support will be enabled.
40  *
41  * For GPU interrupt sources that may be driven by another driver, IRQ domain
42  * support is used (with mapping between virtual and hardware IRQs).
43  */
44 
45 #include <linux/irq.h>
46 #include <linux/pci.h>
47 
48 #include <drm/drm_crtc_helper.h>
49 #include <drm/drm_irq.h>
50 #include <drm/drm_vblank.h>
51 #include <drm/amdgpu_drm.h>
52 #include "amdgpu.h"
53 #include "amdgpu_ih.h"
54 #include "atom.h"
55 #include "amdgpu_connectors.h"
56 #include "amdgpu_trace.h"
57 #include "amdgpu_amdkfd.h"
58 
59 #include <linux/pm_runtime.h>
60 
61 #ifdef CONFIG_DRM_AMD_DC
62 #include "amdgpu_dm_irq.h"
63 #endif
64 
65 #define AMDGPU_WAIT_IDLE_TIMEOUT 200
66 
67 /**
68  * amdgpu_hotplug_work_func - work handler for display hotplug event
69  *
70  * @work: work struct pointer
71  *
72  * This is the hotplug event work handler (all ASICs).
73  * The work gets scheduled from the IRQ handler if there
74  * was a hotplug interrupt.  It walks through the connector table
75  * and calls hotplug handler for each connector. After this, it sends
76  * a DRM hotplug event to alert userspace.
77  *
78  * This design approach is required in order to defer hotplug event handling
79  * from the IRQ handler to a work handler because hotplug handler has to use
80  * mutexes which cannot be locked in an IRQ handler (since &mutex_lock may
81  * sleep).
82  */
83 static void amdgpu_hotplug_work_func(struct work_struct *work)
84 {
85 	struct amdgpu_device *adev = container_of(work, struct amdgpu_device,
86 						  hotplug_work);
87 	struct drm_device *dev = adev->ddev;
88 	struct drm_mode_config *mode_config = &dev->mode_config;
89 	struct drm_connector *connector;
90 
91 	mutex_lock(&mode_config->mutex);
92 	list_for_each_entry(connector, &mode_config->connector_list, head)
93 		amdgpu_connector_hotplug(connector);
94 	mutex_unlock(&mode_config->mutex);
95 	/* Just fire off a uevent and let userspace tell us what to do */
96 	drm_helper_hpd_irq_event(dev);
97 }
98 
99 /**
100  * amdgpu_irq_disable_all - disable *all* interrupts
101  *
102  * @adev: amdgpu device pointer
103  *
104  * Disable all types of interrupts from all sources.
105  */
106 void amdgpu_irq_disable_all(struct amdgpu_device *adev)
107 {
108 	unsigned long irqflags;
109 	unsigned i, j, k;
110 	int r;
111 
112 	spin_lock_irqsave(&adev->irq.lock, irqflags);
113 	for (i = 0; i < AMDGPU_IRQ_CLIENTID_MAX; ++i) {
114 		if (!adev->irq.client[i].sources)
115 			continue;
116 
117 		for (j = 0; j < AMDGPU_MAX_IRQ_SRC_ID; ++j) {
118 			struct amdgpu_irq_src *src = adev->irq.client[i].sources[j];
119 
120 			if (!src || !src->funcs->set || !src->num_types)
121 				continue;
122 
123 			for (k = 0; k < src->num_types; ++k) {
124 				atomic_set(&src->enabled_types[k], 0);
125 				r = src->funcs->set(adev, src, k,
126 						    AMDGPU_IRQ_STATE_DISABLE);
127 				if (r)
128 					DRM_ERROR("error disabling interrupt (%d)\n",
129 						  r);
130 			}
131 		}
132 	}
133 	spin_unlock_irqrestore(&adev->irq.lock, irqflags);
134 }
135 
136 /**
137  * amdgpu_irq_handler - IRQ handler
138  *
139  * @irq: IRQ number (unused)
140  * @arg: pointer to DRM device
141  *
142  * IRQ handler for amdgpu driver (all ASICs).
143  *
144  * Returns:
145  * result of handling the IRQ, as defined by &irqreturn_t
146  */
147 irqreturn_t amdgpu_irq_handler(int irq, void *arg)
148 {
149 	struct drm_device *dev = (struct drm_device *) arg;
150 	struct amdgpu_device *adev = dev->dev_private;
151 	irqreturn_t ret;
152 
153 	ret = amdgpu_ih_process(adev, &adev->irq.ih);
154 	if (ret == IRQ_HANDLED)
155 		pm_runtime_mark_last_busy(dev->dev);
156 	return ret;
157 }
158 
159 /**
160  * amdgpu_irq_handle_ih1 - kick of processing for IH1
161  *
162  * @work: work structure in struct amdgpu_irq
163  *
164  * Kick of processing IH ring 1.
165  */
166 static void amdgpu_irq_handle_ih1(struct work_struct *work)
167 {
168 	struct amdgpu_device *adev = container_of(work, struct amdgpu_device,
169 						  irq.ih1_work);
170 
171 	amdgpu_ih_process(adev, &adev->irq.ih1);
172 }
173 
174 /**
175  * amdgpu_irq_handle_ih2 - kick of processing for IH2
176  *
177  * @work: work structure in struct amdgpu_irq
178  *
179  * Kick of processing IH ring 2.
180  */
181 static void amdgpu_irq_handle_ih2(struct work_struct *work)
182 {
183 	struct amdgpu_device *adev = container_of(work, struct amdgpu_device,
184 						  irq.ih2_work);
185 
186 	amdgpu_ih_process(adev, &adev->irq.ih2);
187 }
188 
189 /**
190  * amdgpu_msi_ok - check whether MSI functionality is enabled
191  *
192  * @adev: amdgpu device pointer (unused)
193  *
194  * Checks whether MSI functionality has been disabled via module parameter
195  * (all ASICs).
196  *
197  * Returns:
198  * *true* if MSIs are allowed to be enabled or *false* otherwise
199  */
200 static bool amdgpu_msi_ok(struct amdgpu_device *adev)
201 {
202 	if (amdgpu_msi == 1)
203 		return true;
204 	else if (amdgpu_msi == 0)
205 		return false;
206 
207 	return true;
208 }
209 
210 /**
211  * amdgpu_irq_init - initialize interrupt handling
212  *
213  * @adev: amdgpu device pointer
214  *
215  * Sets up work functions for hotplug and reset interrupts, enables MSI
216  * functionality, initializes vblank, hotplug and reset interrupt handling.
217  *
218  * Returns:
219  * 0 on success or error code on failure
220  */
221 int amdgpu_irq_init(struct amdgpu_device *adev)
222 {
223 	int r = 0;
224 
225 	spin_lock_init(&adev->irq.lock);
226 
227 	/* Enable MSI if not disabled by module parameter */
228 	adev->irq.msi_enabled = false;
229 
230 	if (amdgpu_msi_ok(adev)) {
231 		int ret = pci_enable_msi(adev->pdev);
232 		if (!ret) {
233 			adev->irq.msi_enabled = true;
234 			dev_dbg(adev->dev, "amdgpu: using MSI.\n");
235 		}
236 	}
237 
238 	if (!amdgpu_device_has_dc_support(adev)) {
239 		if (!adev->enable_virtual_display)
240 			/* Disable vblank IRQs aggressively for power-saving */
241 			/* XXX: can this be enabled for DC? */
242 			adev->ddev->vblank_disable_immediate = true;
243 
244 		r = drm_vblank_init(adev->ddev, adev->mode_info.num_crtc);
245 		if (r)
246 			return r;
247 
248 		/* Pre-DCE11 */
249 		INIT_WORK(&adev->hotplug_work,
250 				amdgpu_hotplug_work_func);
251 	}
252 
253 	INIT_WORK(&adev->irq.ih1_work, amdgpu_irq_handle_ih1);
254 	INIT_WORK(&adev->irq.ih2_work, amdgpu_irq_handle_ih2);
255 
256 	adev->irq.installed = true;
257 	r = drm_irq_install(adev->ddev, adev->ddev->pdev->irq);
258 	if (r) {
259 		adev->irq.installed = false;
260 		if (!amdgpu_device_has_dc_support(adev))
261 			flush_work(&adev->hotplug_work);
262 		return r;
263 	}
264 	adev->ddev->max_vblank_count = 0x00ffffff;
265 
266 	DRM_DEBUG("amdgpu: irq initialized.\n");
267 	return 0;
268 }
269 
270 /**
271  * amdgpu_irq_fini - shut down interrupt handling
272  *
273  * @adev: amdgpu device pointer
274  *
275  * Tears down work functions for hotplug and reset interrupts, disables MSI
276  * functionality, shuts down vblank, hotplug and reset interrupt handling,
277  * turns off interrupts from all sources (all ASICs).
278  */
279 void amdgpu_irq_fini(struct amdgpu_device *adev)
280 {
281 	unsigned i, j;
282 
283 	if (adev->irq.installed) {
284 		drm_irq_uninstall(adev->ddev);
285 		adev->irq.installed = false;
286 		if (adev->irq.msi_enabled)
287 			pci_disable_msi(adev->pdev);
288 		if (!amdgpu_device_has_dc_support(adev))
289 			flush_work(&adev->hotplug_work);
290 	}
291 
292 	for (i = 0; i < AMDGPU_IRQ_CLIENTID_MAX; ++i) {
293 		if (!adev->irq.client[i].sources)
294 			continue;
295 
296 		for (j = 0; j < AMDGPU_MAX_IRQ_SRC_ID; ++j) {
297 			struct amdgpu_irq_src *src = adev->irq.client[i].sources[j];
298 
299 			if (!src)
300 				continue;
301 
302 			kfree(src->enabled_types);
303 			src->enabled_types = NULL;
304 			if (src->data) {
305 				kfree(src->data);
306 				kfree(src);
307 				adev->irq.client[i].sources[j] = NULL;
308 			}
309 		}
310 		kfree(adev->irq.client[i].sources);
311 		adev->irq.client[i].sources = NULL;
312 	}
313 }
314 
315 /**
316  * amdgpu_irq_add_id - register IRQ source
317  *
318  * @adev: amdgpu device pointer
319  * @client_id: client id
320  * @src_id: source id
321  * @source: IRQ source pointer
322  *
323  * Registers IRQ source on a client.
324  *
325  * Returns:
326  * 0 on success or error code otherwise
327  */
328 int amdgpu_irq_add_id(struct amdgpu_device *adev,
329 		      unsigned client_id, unsigned src_id,
330 		      struct amdgpu_irq_src *source)
331 {
332 	if (client_id >= AMDGPU_IRQ_CLIENTID_MAX)
333 		return -EINVAL;
334 
335 	if (src_id >= AMDGPU_MAX_IRQ_SRC_ID)
336 		return -EINVAL;
337 
338 	if (!source->funcs)
339 		return -EINVAL;
340 
341 	if (!adev->irq.client[client_id].sources) {
342 		adev->irq.client[client_id].sources =
343 			kcalloc(AMDGPU_MAX_IRQ_SRC_ID,
344 				sizeof(struct amdgpu_irq_src *),
345 				GFP_KERNEL);
346 		if (!adev->irq.client[client_id].sources)
347 			return -ENOMEM;
348 	}
349 
350 	if (adev->irq.client[client_id].sources[src_id] != NULL)
351 		return -EINVAL;
352 
353 	if (source->num_types && !source->enabled_types) {
354 		atomic_t *types;
355 
356 		types = kcalloc(source->num_types, sizeof(atomic_t),
357 				GFP_KERNEL);
358 		if (!types)
359 			return -ENOMEM;
360 
361 		source->enabled_types = types;
362 	}
363 
364 	adev->irq.client[client_id].sources[src_id] = source;
365 	return 0;
366 }
367 
368 /**
369  * amdgpu_irq_dispatch - dispatch IRQ to IP blocks
370  *
371  * @adev: amdgpu device pointer
372  * @entry: interrupt vector pointer
373  *
374  * Dispatches IRQ to IP blocks.
375  */
376 void amdgpu_irq_dispatch(struct amdgpu_device *adev,
377 			 struct amdgpu_ih_ring *ih)
378 {
379 	u32 ring_index = ih->rptr >> 2;
380 	struct amdgpu_iv_entry entry;
381 	unsigned client_id, src_id;
382 	struct amdgpu_irq_src *src;
383 	bool handled = false;
384 	int r;
385 
386 	entry.iv_entry = (const uint32_t *)&ih->ring[ring_index];
387 	amdgpu_ih_decode_iv(adev, &entry);
388 
389 	trace_amdgpu_iv(ih - &adev->irq.ih, &entry);
390 
391 	client_id = entry.client_id;
392 	src_id = entry.src_id;
393 
394 	if (client_id >= AMDGPU_IRQ_CLIENTID_MAX) {
395 		DRM_DEBUG("Invalid client_id in IV: %d\n", client_id);
396 
397 	} else	if (src_id >= AMDGPU_MAX_IRQ_SRC_ID) {
398 		DRM_DEBUG("Invalid src_id in IV: %d\n", src_id);
399 
400 	} else if (adev->irq.virq[src_id]) {
401 		generic_handle_irq(irq_find_mapping(adev->irq.domain, src_id));
402 
403 	} else if (!adev->irq.client[client_id].sources) {
404 		DRM_DEBUG("Unregistered interrupt client_id: %d src_id: %d\n",
405 			  client_id, src_id);
406 
407 	} else if ((src = adev->irq.client[client_id].sources[src_id])) {
408 		r = src->funcs->process(adev, src, &entry);
409 		if (r < 0)
410 			DRM_ERROR("error processing interrupt (%d)\n", r);
411 		else if (r)
412 			handled = true;
413 
414 	} else {
415 		DRM_DEBUG("Unhandled interrupt src_id: %d\n", src_id);
416 	}
417 
418 	/* Send it to amdkfd as well if it isn't already handled */
419 	if (!handled)
420 		amdgpu_amdkfd_interrupt(adev, entry.iv_entry);
421 }
422 
423 /**
424  * amdgpu_irq_update - update hardware interrupt state
425  *
426  * @adev: amdgpu device pointer
427  * @src: interrupt source pointer
428  * @type: type of interrupt
429  *
430  * Updates interrupt state for the specific source (all ASICs).
431  */
432 int amdgpu_irq_update(struct amdgpu_device *adev,
433 			     struct amdgpu_irq_src *src, unsigned type)
434 {
435 	unsigned long irqflags;
436 	enum amdgpu_interrupt_state state;
437 	int r;
438 
439 	spin_lock_irqsave(&adev->irq.lock, irqflags);
440 
441 	/* We need to determine after taking the lock, otherwise
442 	   we might disable just enabled interrupts again */
443 	if (amdgpu_irq_enabled(adev, src, type))
444 		state = AMDGPU_IRQ_STATE_ENABLE;
445 	else
446 		state = AMDGPU_IRQ_STATE_DISABLE;
447 
448 	r = src->funcs->set(adev, src, type, state);
449 	spin_unlock_irqrestore(&adev->irq.lock, irqflags);
450 	return r;
451 }
452 
453 /**
454  * amdgpu_irq_gpu_reset_resume_helper - update interrupt states on all sources
455  *
456  * @adev: amdgpu device pointer
457  *
458  * Updates state of all types of interrupts on all sources on resume after
459  * reset.
460  */
461 void amdgpu_irq_gpu_reset_resume_helper(struct amdgpu_device *adev)
462 {
463 	int i, j, k;
464 
465 	for (i = 0; i < AMDGPU_IRQ_CLIENTID_MAX; ++i) {
466 		if (!adev->irq.client[i].sources)
467 			continue;
468 
469 		for (j = 0; j < AMDGPU_MAX_IRQ_SRC_ID; ++j) {
470 			struct amdgpu_irq_src *src = adev->irq.client[i].sources[j];
471 
472 			if (!src)
473 				continue;
474 			for (k = 0; k < src->num_types; k++)
475 				amdgpu_irq_update(adev, src, k);
476 		}
477 	}
478 }
479 
480 /**
481  * amdgpu_irq_get - enable interrupt
482  *
483  * @adev: amdgpu device pointer
484  * @src: interrupt source pointer
485  * @type: type of interrupt
486  *
487  * Enables specified type of interrupt on the specified source (all ASICs).
488  *
489  * Returns:
490  * 0 on success or error code otherwise
491  */
492 int amdgpu_irq_get(struct amdgpu_device *adev, struct amdgpu_irq_src *src,
493 		   unsigned type)
494 {
495 	if (!adev->ddev->irq_enabled)
496 		return -ENOENT;
497 
498 	if (type >= src->num_types)
499 		return -EINVAL;
500 
501 	if (!src->enabled_types || !src->funcs->set)
502 		return -EINVAL;
503 
504 	if (atomic_inc_return(&src->enabled_types[type]) == 1)
505 		return amdgpu_irq_update(adev, src, type);
506 
507 	return 0;
508 }
509 
510 /**
511  * amdgpu_irq_put - disable interrupt
512  *
513  * @adev: amdgpu device pointer
514  * @src: interrupt source pointer
515  * @type: type of interrupt
516  *
517  * Enables specified type of interrupt on the specified source (all ASICs).
518  *
519  * Returns:
520  * 0 on success or error code otherwise
521  */
522 int amdgpu_irq_put(struct amdgpu_device *adev, struct amdgpu_irq_src *src,
523 		   unsigned type)
524 {
525 	if (!adev->ddev->irq_enabled)
526 		return -ENOENT;
527 
528 	if (type >= src->num_types)
529 		return -EINVAL;
530 
531 	if (!src->enabled_types || !src->funcs->set)
532 		return -EINVAL;
533 
534 	if (atomic_dec_and_test(&src->enabled_types[type]))
535 		return amdgpu_irq_update(adev, src, type);
536 
537 	return 0;
538 }
539 
540 /**
541  * amdgpu_irq_enabled - check whether interrupt is enabled or not
542  *
543  * @adev: amdgpu device pointer
544  * @src: interrupt source pointer
545  * @type: type of interrupt
546  *
547  * Checks whether the given type of interrupt is enabled on the given source.
548  *
549  * Returns:
550  * *true* if interrupt is enabled, *false* if interrupt is disabled or on
551  * invalid parameters
552  */
553 bool amdgpu_irq_enabled(struct amdgpu_device *adev, struct amdgpu_irq_src *src,
554 			unsigned type)
555 {
556 	if (!adev->ddev->irq_enabled)
557 		return false;
558 
559 	if (type >= src->num_types)
560 		return false;
561 
562 	if (!src->enabled_types || !src->funcs->set)
563 		return false;
564 
565 	return !!atomic_read(&src->enabled_types[type]);
566 }
567 
568 /* XXX: Generic IRQ handling */
569 static void amdgpu_irq_mask(struct irq_data *irqd)
570 {
571 	/* XXX */
572 }
573 
574 static void amdgpu_irq_unmask(struct irq_data *irqd)
575 {
576 	/* XXX */
577 }
578 
579 /* amdgpu hardware interrupt chip descriptor */
580 static struct irq_chip amdgpu_irq_chip = {
581 	.name = "amdgpu-ih",
582 	.irq_mask = amdgpu_irq_mask,
583 	.irq_unmask = amdgpu_irq_unmask,
584 };
585 
586 /**
587  * amdgpu_irqdomain_map - create mapping between virtual and hardware IRQ numbers
588  *
589  * @d: amdgpu IRQ domain pointer (unused)
590  * @irq: virtual IRQ number
591  * @hwirq: hardware irq number
592  *
593  * Current implementation assigns simple interrupt handler to the given virtual
594  * IRQ.
595  *
596  * Returns:
597  * 0 on success or error code otherwise
598  */
599 static int amdgpu_irqdomain_map(struct irq_domain *d,
600 				unsigned int irq, irq_hw_number_t hwirq)
601 {
602 	if (hwirq >= AMDGPU_MAX_IRQ_SRC_ID)
603 		return -EPERM;
604 
605 	irq_set_chip_and_handler(irq,
606 				 &amdgpu_irq_chip, handle_simple_irq);
607 	return 0;
608 }
609 
610 /* Implementation of methods for amdgpu IRQ domain */
611 static const struct irq_domain_ops amdgpu_hw_irqdomain_ops = {
612 	.map = amdgpu_irqdomain_map,
613 };
614 
615 /**
616  * amdgpu_irq_add_domain - create a linear IRQ domain
617  *
618  * @adev: amdgpu device pointer
619  *
620  * Creates an IRQ domain for GPU interrupt sources
621  * that may be driven by another driver (e.g., ACP).
622  *
623  * Returns:
624  * 0 on success or error code otherwise
625  */
626 int amdgpu_irq_add_domain(struct amdgpu_device *adev)
627 {
628 	adev->irq.domain = irq_domain_add_linear(NULL, AMDGPU_MAX_IRQ_SRC_ID,
629 						 &amdgpu_hw_irqdomain_ops, adev);
630 	if (!adev->irq.domain) {
631 		DRM_ERROR("GPU irq add domain failed\n");
632 		return -ENODEV;
633 	}
634 
635 	return 0;
636 }
637 
638 /**
639  * amdgpu_irq_remove_domain - remove the IRQ domain
640  *
641  * @adev: amdgpu device pointer
642  *
643  * Removes the IRQ domain for GPU interrupt sources
644  * that may be driven by another driver (e.g., ACP).
645  */
646 void amdgpu_irq_remove_domain(struct amdgpu_device *adev)
647 {
648 	if (adev->irq.domain) {
649 		irq_domain_remove(adev->irq.domain);
650 		adev->irq.domain = NULL;
651 	}
652 }
653 
654 /**
655  * amdgpu_irq_create_mapping - create mapping between domain Linux IRQs
656  *
657  * @adev: amdgpu device pointer
658  * @src_id: IH source id
659  *
660  * Creates mapping between a domain IRQ (GPU IH src id) and a Linux IRQ
661  * Use this for components that generate a GPU interrupt, but are driven
662  * by a different driver (e.g., ACP).
663  *
664  * Returns:
665  * Linux IRQ
666  */
667 unsigned amdgpu_irq_create_mapping(struct amdgpu_device *adev, unsigned src_id)
668 {
669 	adev->irq.virq[src_id] = irq_create_mapping(adev->irq.domain, src_id);
670 
671 	return adev->irq.virq[src_id];
672 }
673