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