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