1 // SPDX-License-Identifier: MIT
2 /*
3  * Copyright © 2014-2019 Intel Corporation
4  */
5 
6 #include <linux/debugfs.h>
7 #include <linux/string_helpers.h>
8 
9 #include "gt/intel_gt.h"
10 #include "i915_drv.h"
11 #include "i915_irq.h"
12 #include "i915_memcpy.h"
13 #include "intel_guc_capture.h"
14 #include "intel_guc_log.h"
15 
16 #if defined(CONFIG_DRM_I915_DEBUG_GUC)
17 #define GUC_LOG_DEFAULT_CRASH_BUFFER_SIZE	SZ_2M
18 #define GUC_LOG_DEFAULT_DEBUG_BUFFER_SIZE	SZ_16M
19 #define GUC_LOG_DEFAULT_CAPTURE_BUFFER_SIZE	SZ_4M
20 #elif defined(CONFIG_DRM_I915_DEBUG_GEM)
21 #define GUC_LOG_DEFAULT_CRASH_BUFFER_SIZE	SZ_1M
22 #define GUC_LOG_DEFAULT_DEBUG_BUFFER_SIZE	SZ_2M
23 #define GUC_LOG_DEFAULT_CAPTURE_BUFFER_SIZE	SZ_4M
24 #else
25 #define GUC_LOG_DEFAULT_CRASH_BUFFER_SIZE	SZ_8K
26 #define GUC_LOG_DEFAULT_DEBUG_BUFFER_SIZE	SZ_64K
27 #define GUC_LOG_DEFAULT_CAPTURE_BUFFER_SIZE	SZ_2M
28 #endif
29 
30 static void guc_log_copy_debuglogs_for_relay(struct intel_guc_log *log);
31 
32 struct guc_log_section {
33 	u32 max;
34 	u32 flag;
35 	u32 default_val;
36 	const char *name;
37 };
38 
39 static s32 scale_log_param(struct intel_guc_log *log, const struct guc_log_section *section,
40 			   s32 param)
41 {
42 	/* -1 means default */
43 	if (param < 0)
44 		return section->default_val;
45 
46 	/* Check for 32-bit overflow */
47 	if (param >= SZ_4K) {
48 		drm_err(&guc_to_gt(log_to_guc(log))->i915->drm, "Size too large for GuC %s log: %dMB!",
49 			section->name, param);
50 		return section->default_val;
51 	}
52 
53 	/* Param units are 1MB */
54 	return param * SZ_1M;
55 }
56 
57 static void _guc_log_init_sizes(struct intel_guc_log *log)
58 {
59 	struct intel_guc *guc = log_to_guc(log);
60 	struct drm_i915_private *i915 = guc_to_gt(guc)->i915;
61 	static const struct guc_log_section sections[GUC_LOG_SECTIONS_LIMIT] = {
62 		{
63 			GUC_LOG_CRASH_MASK >> GUC_LOG_CRASH_SHIFT,
64 			GUC_LOG_LOG_ALLOC_UNITS,
65 			GUC_LOG_DEFAULT_CRASH_BUFFER_SIZE,
66 			"crash dump"
67 		},
68 		{
69 			GUC_LOG_DEBUG_MASK >> GUC_LOG_DEBUG_SHIFT,
70 			GUC_LOG_LOG_ALLOC_UNITS,
71 			GUC_LOG_DEFAULT_DEBUG_BUFFER_SIZE,
72 			"debug",
73 		},
74 		{
75 			GUC_LOG_CAPTURE_MASK >> GUC_LOG_CAPTURE_SHIFT,
76 			GUC_LOG_CAPTURE_ALLOC_UNITS,
77 			GUC_LOG_DEFAULT_CAPTURE_BUFFER_SIZE,
78 			"capture",
79 		}
80 	};
81 	s32 params[GUC_LOG_SECTIONS_LIMIT] = {
82 		GUC_LOG_DEFAULT_CRASH_BUFFER_SIZE / SZ_1M,
83 		GUC_LOG_DEFAULT_DEBUG_BUFFER_SIZE / SZ_1M,
84 		GUC_LOG_DEFAULT_CAPTURE_BUFFER_SIZE / SZ_1M,
85 	};
86 	int i;
87 
88 	for (i = 0; i < GUC_LOG_SECTIONS_LIMIT; i++)
89 		log->sizes[i].bytes = scale_log_param(log, sections + i, params[i]);
90 
91 	/* If debug size > 1MB then bump default crash size to keep the same units */
92 	if (log->sizes[GUC_LOG_SECTIONS_DEBUG].bytes >= SZ_1M &&
93 	    GUC_LOG_DEFAULT_CRASH_BUFFER_SIZE < SZ_1M)
94 		log->sizes[GUC_LOG_SECTIONS_CRASH].bytes = SZ_1M;
95 
96 	/* Prepare the GuC API structure fields: */
97 	for (i = 0; i < GUC_LOG_SECTIONS_LIMIT; i++) {
98 		/* Convert to correct units */
99 		if ((log->sizes[i].bytes % SZ_1M) == 0) {
100 			log->sizes[i].units = SZ_1M;
101 			log->sizes[i].flag = sections[i].flag;
102 		} else {
103 			log->sizes[i].units = SZ_4K;
104 			log->sizes[i].flag = 0;
105 		}
106 
107 		if (!IS_ALIGNED(log->sizes[i].bytes, log->sizes[i].units))
108 			drm_err(&i915->drm, "Mis-aligned GuC log %s size: 0x%X vs 0x%X!",
109 				sections[i].name, log->sizes[i].bytes, log->sizes[i].units);
110 		log->sizes[i].count = log->sizes[i].bytes / log->sizes[i].units;
111 
112 		if (!log->sizes[i].count) {
113 			drm_err(&i915->drm, "Zero GuC log %s size!", sections[i].name);
114 		} else {
115 			/* Size is +1 unit */
116 			log->sizes[i].count--;
117 		}
118 
119 		/* Clip to field size */
120 		if (log->sizes[i].count > sections[i].max) {
121 			drm_err(&i915->drm, "GuC log %s size too large: %d vs %d!",
122 				sections[i].name, log->sizes[i].count + 1, sections[i].max + 1);
123 			log->sizes[i].count = sections[i].max;
124 		}
125 	}
126 
127 	if (log->sizes[GUC_LOG_SECTIONS_CRASH].units != log->sizes[GUC_LOG_SECTIONS_DEBUG].units) {
128 		drm_err(&i915->drm, "Unit mis-match for GuC log crash and debug sections: %d vs %d!",
129 			log->sizes[GUC_LOG_SECTIONS_CRASH].units,
130 			log->sizes[GUC_LOG_SECTIONS_DEBUG].units);
131 		log->sizes[GUC_LOG_SECTIONS_CRASH].units = log->sizes[GUC_LOG_SECTIONS_DEBUG].units;
132 		log->sizes[GUC_LOG_SECTIONS_CRASH].count = 0;
133 	}
134 
135 	log->sizes_initialised = true;
136 }
137 
138 static void guc_log_init_sizes(struct intel_guc_log *log)
139 {
140 	if (log->sizes_initialised)
141 		return;
142 
143 	_guc_log_init_sizes(log);
144 }
145 
146 static u32 intel_guc_log_section_size_crash(struct intel_guc_log *log)
147 {
148 	guc_log_init_sizes(log);
149 
150 	return log->sizes[GUC_LOG_SECTIONS_CRASH].bytes;
151 }
152 
153 static u32 intel_guc_log_section_size_debug(struct intel_guc_log *log)
154 {
155 	guc_log_init_sizes(log);
156 
157 	return log->sizes[GUC_LOG_SECTIONS_DEBUG].bytes;
158 }
159 
160 u32 intel_guc_log_section_size_capture(struct intel_guc_log *log)
161 {
162 	guc_log_init_sizes(log);
163 
164 	return log->sizes[GUC_LOG_SECTIONS_CAPTURE].bytes;
165 }
166 
167 static u32 intel_guc_log_size(struct intel_guc_log *log)
168 {
169 	/*
170 	 *  GuC Log buffer Layout:
171 	 *
172 	 *  NB: Ordering must follow "enum guc_log_buffer_type".
173 	 *
174 	 *  +===============================+ 00B
175 	 *  |      Debug state header       |
176 	 *  +-------------------------------+ 32B
177 	 *  |    Crash dump state header    |
178 	 *  +-------------------------------+ 64B
179 	 *  |     Capture state header      |
180 	 *  +-------------------------------+ 96B
181 	 *  |                               |
182 	 *  +===============================+ PAGE_SIZE (4KB)
183 	 *  |          Debug logs           |
184 	 *  +===============================+ + DEBUG_SIZE
185 	 *  |        Crash Dump logs        |
186 	 *  +===============================+ + CRASH_SIZE
187 	 *  |         Capture logs          |
188 	 *  +===============================+ + CAPTURE_SIZE
189 	 */
190 	return PAGE_SIZE +
191 		intel_guc_log_section_size_crash(log) +
192 		intel_guc_log_section_size_debug(log) +
193 		intel_guc_log_section_size_capture(log);
194 }
195 
196 /**
197  * DOC: GuC firmware log
198  *
199  * Firmware log is enabled by setting i915.guc_log_level to the positive level.
200  * Log data is printed out via reading debugfs i915_guc_log_dump. Reading from
201  * i915_guc_load_status will print out firmware loading status and scratch
202  * registers value.
203  */
204 
205 static int guc_action_flush_log_complete(struct intel_guc *guc)
206 {
207 	u32 action[] = {
208 		INTEL_GUC_ACTION_LOG_BUFFER_FILE_FLUSH_COMPLETE,
209 		GUC_DEBUG_LOG_BUFFER
210 	};
211 
212 	return intel_guc_send_nb(guc, action, ARRAY_SIZE(action), 0);
213 }
214 
215 static int guc_action_flush_log(struct intel_guc *guc)
216 {
217 	u32 action[] = {
218 		INTEL_GUC_ACTION_FORCE_LOG_BUFFER_FLUSH,
219 		0
220 	};
221 
222 	return intel_guc_send(guc, action, ARRAY_SIZE(action));
223 }
224 
225 static int guc_action_control_log(struct intel_guc *guc, bool enable,
226 				  bool default_logging, u32 verbosity)
227 {
228 	u32 action[] = {
229 		INTEL_GUC_ACTION_UK_LOG_ENABLE_LOGGING,
230 		(enable ? GUC_LOG_CONTROL_LOGGING_ENABLED : 0) |
231 		(verbosity << GUC_LOG_CONTROL_VERBOSITY_SHIFT) |
232 		(default_logging ? GUC_LOG_CONTROL_DEFAULT_LOGGING : 0)
233 	};
234 
235 	GEM_BUG_ON(verbosity > GUC_LOG_VERBOSITY_MAX);
236 
237 	return intel_guc_send(guc, action, ARRAY_SIZE(action));
238 }
239 
240 /*
241  * Sub buffer switch callback. Called whenever relay has to switch to a new
242  * sub buffer, relay stays on the same sub buffer if 0 is returned.
243  */
244 static int subbuf_start_callback(struct rchan_buf *buf,
245 				 void *subbuf,
246 				 void *prev_subbuf,
247 				 size_t prev_padding)
248 {
249 	/*
250 	 * Use no-overwrite mode by default, where relay will stop accepting
251 	 * new data if there are no empty sub buffers left.
252 	 * There is no strict synchronization enforced by relay between Consumer
253 	 * and Producer. In overwrite mode, there is a possibility of getting
254 	 * inconsistent/garbled data, the producer could be writing on to the
255 	 * same sub buffer from which Consumer is reading. This can't be avoided
256 	 * unless Consumer is fast enough and can always run in tandem with
257 	 * Producer.
258 	 */
259 	if (relay_buf_full(buf))
260 		return 0;
261 
262 	return 1;
263 }
264 
265 /*
266  * file_create() callback. Creates relay file in debugfs.
267  */
268 static struct dentry *create_buf_file_callback(const char *filename,
269 					       struct dentry *parent,
270 					       umode_t mode,
271 					       struct rchan_buf *buf,
272 					       int *is_global)
273 {
274 	struct dentry *buf_file;
275 
276 	/*
277 	 * This to enable the use of a single buffer for the relay channel and
278 	 * correspondingly have a single file exposed to User, through which
279 	 * it can collect the logs in order without any post-processing.
280 	 * Need to set 'is_global' even if parent is NULL for early logging.
281 	 */
282 	*is_global = 1;
283 
284 	if (!parent)
285 		return NULL;
286 
287 	buf_file = debugfs_create_file(filename, mode,
288 				       parent, buf, &relay_file_operations);
289 	if (IS_ERR(buf_file))
290 		return NULL;
291 
292 	return buf_file;
293 }
294 
295 /*
296  * file_remove() default callback. Removes relay file in debugfs.
297  */
298 static int remove_buf_file_callback(struct dentry *dentry)
299 {
300 	debugfs_remove(dentry);
301 	return 0;
302 }
303 
304 /* relay channel callbacks */
305 static const struct rchan_callbacks relay_callbacks = {
306 	.subbuf_start = subbuf_start_callback,
307 	.create_buf_file = create_buf_file_callback,
308 	.remove_buf_file = remove_buf_file_callback,
309 };
310 
311 static void guc_move_to_next_buf(struct intel_guc_log *log)
312 {
313 	/*
314 	 * Make sure the updates made in the sub buffer are visible when
315 	 * Consumer sees the following update to offset inside the sub buffer.
316 	 */
317 	smp_wmb();
318 
319 	/* All data has been written, so now move the offset of sub buffer. */
320 	relay_reserve(log->relay.channel, log->vma->obj->base.size -
321 					  intel_guc_log_section_size_capture(log));
322 
323 	/* Switch to the next sub buffer */
324 	relay_flush(log->relay.channel);
325 }
326 
327 static void *guc_get_write_buffer(struct intel_guc_log *log)
328 {
329 	/*
330 	 * Just get the base address of a new sub buffer and copy data into it
331 	 * ourselves. NULL will be returned in no-overwrite mode, if all sub
332 	 * buffers are full. Could have used the relay_write() to indirectly
333 	 * copy the data, but that would have been bit convoluted, as we need to
334 	 * write to only certain locations inside a sub buffer which cannot be
335 	 * done without using relay_reserve() along with relay_write(). So its
336 	 * better to use relay_reserve() alone.
337 	 */
338 	return relay_reserve(log->relay.channel, 0);
339 }
340 
341 bool intel_guc_check_log_buf_overflow(struct intel_guc_log *log,
342 				      enum guc_log_buffer_type type,
343 				      unsigned int full_cnt)
344 {
345 	unsigned int prev_full_cnt = log->stats[type].sampled_overflow;
346 	bool overflow = false;
347 
348 	if (full_cnt != prev_full_cnt) {
349 		overflow = true;
350 
351 		log->stats[type].overflow = full_cnt;
352 		log->stats[type].sampled_overflow += full_cnt - prev_full_cnt;
353 
354 		if (full_cnt < prev_full_cnt) {
355 			/* buffer_full_cnt is a 4 bit counter */
356 			log->stats[type].sampled_overflow += 16;
357 		}
358 
359 		dev_notice_ratelimited(guc_to_gt(log_to_guc(log))->i915->drm.dev,
360 				       "GuC log buffer overflow\n");
361 	}
362 
363 	return overflow;
364 }
365 
366 unsigned int intel_guc_get_log_buffer_size(struct intel_guc_log *log,
367 					   enum guc_log_buffer_type type)
368 {
369 	switch (type) {
370 	case GUC_DEBUG_LOG_BUFFER:
371 		return intel_guc_log_section_size_debug(log);
372 	case GUC_CRASH_DUMP_LOG_BUFFER:
373 		return intel_guc_log_section_size_crash(log);
374 	case GUC_CAPTURE_LOG_BUFFER:
375 		return intel_guc_log_section_size_capture(log);
376 	default:
377 		MISSING_CASE(type);
378 	}
379 
380 	return 0;
381 }
382 
383 size_t intel_guc_get_log_buffer_offset(struct intel_guc_log *log,
384 				       enum guc_log_buffer_type type)
385 {
386 	enum guc_log_buffer_type i;
387 	size_t offset = PAGE_SIZE;/* for the log_buffer_states */
388 
389 	for (i = GUC_DEBUG_LOG_BUFFER; i < GUC_MAX_LOG_BUFFER; ++i) {
390 		if (i == type)
391 			break;
392 		offset += intel_guc_get_log_buffer_size(log, i);
393 	}
394 
395 	return offset;
396 }
397 
398 static void _guc_log_copy_debuglogs_for_relay(struct intel_guc_log *log)
399 {
400 	unsigned int buffer_size, read_offset, write_offset, bytes_to_copy, full_cnt;
401 	struct guc_log_buffer_state *log_buf_state, *log_buf_snapshot_state;
402 	struct guc_log_buffer_state log_buf_state_local;
403 	enum guc_log_buffer_type type;
404 	void *src_data, *dst_data;
405 	bool new_overflow;
406 
407 	mutex_lock(&log->relay.lock);
408 
409 	if (WARN_ON(!intel_guc_log_relay_created(log)))
410 		goto out_unlock;
411 
412 	/* Get the pointer to shared GuC log buffer */
413 	src_data = log->buf_addr;
414 	log_buf_state = src_data;
415 
416 	/* Get the pointer to local buffer to store the logs */
417 	log_buf_snapshot_state = dst_data = guc_get_write_buffer(log);
418 
419 	if (unlikely(!log_buf_snapshot_state)) {
420 		/*
421 		 * Used rate limited to avoid deluge of messages, logs might be
422 		 * getting consumed by User at a slow rate.
423 		 */
424 		DRM_ERROR_RATELIMITED("no sub-buffer to copy general logs\n");
425 		log->relay.full_count++;
426 
427 		goto out_unlock;
428 	}
429 
430 	/* Actual logs are present from the 2nd page */
431 	src_data += PAGE_SIZE;
432 	dst_data += PAGE_SIZE;
433 
434 	/* For relay logging, we exclude error state capture */
435 	for (type = GUC_DEBUG_LOG_BUFFER; type <= GUC_CRASH_DUMP_LOG_BUFFER; type++) {
436 		/*
437 		 * Make a copy of the state structure, inside GuC log buffer
438 		 * (which is uncached mapped), on the stack to avoid reading
439 		 * from it multiple times.
440 		 */
441 		memcpy(&log_buf_state_local, log_buf_state,
442 		       sizeof(struct guc_log_buffer_state));
443 		buffer_size = intel_guc_get_log_buffer_size(log, type);
444 		read_offset = log_buf_state_local.read_ptr;
445 		write_offset = log_buf_state_local.sampled_write_ptr;
446 		full_cnt = log_buf_state_local.buffer_full_cnt;
447 
448 		/* Bookkeeping stuff */
449 		log->stats[type].flush += log_buf_state_local.flush_to_file;
450 		new_overflow = intel_guc_check_log_buf_overflow(log, type, full_cnt);
451 
452 		/* Update the state of shared log buffer */
453 		log_buf_state->read_ptr = write_offset;
454 		log_buf_state->flush_to_file = 0;
455 		log_buf_state++;
456 
457 		/* First copy the state structure in snapshot buffer */
458 		memcpy(log_buf_snapshot_state, &log_buf_state_local,
459 		       sizeof(struct guc_log_buffer_state));
460 
461 		/*
462 		 * The write pointer could have been updated by GuC firmware,
463 		 * after sending the flush interrupt to Host, for consistency
464 		 * set write pointer value to same value of sampled_write_ptr
465 		 * in the snapshot buffer.
466 		 */
467 		log_buf_snapshot_state->write_ptr = write_offset;
468 		log_buf_snapshot_state++;
469 
470 		/* Now copy the actual logs. */
471 		if (unlikely(new_overflow)) {
472 			/* copy the whole buffer in case of overflow */
473 			read_offset = 0;
474 			write_offset = buffer_size;
475 		} else if (unlikely((read_offset > buffer_size) ||
476 				    (write_offset > buffer_size))) {
477 			DRM_ERROR("invalid log buffer state\n");
478 			/* copy whole buffer as offsets are unreliable */
479 			read_offset = 0;
480 			write_offset = buffer_size;
481 		}
482 
483 		/* Just copy the newly written data */
484 		if (read_offset > write_offset) {
485 			i915_memcpy_from_wc(dst_data, src_data, write_offset);
486 			bytes_to_copy = buffer_size - read_offset;
487 		} else {
488 			bytes_to_copy = write_offset - read_offset;
489 		}
490 		i915_memcpy_from_wc(dst_data + read_offset,
491 				    src_data + read_offset, bytes_to_copy);
492 
493 		src_data += buffer_size;
494 		dst_data += buffer_size;
495 	}
496 
497 	guc_move_to_next_buf(log);
498 
499 out_unlock:
500 	mutex_unlock(&log->relay.lock);
501 }
502 
503 static void copy_debug_logs_work(struct work_struct *work)
504 {
505 	struct intel_guc_log *log =
506 		container_of(work, struct intel_guc_log, relay.flush_work);
507 
508 	guc_log_copy_debuglogs_for_relay(log);
509 }
510 
511 static int guc_log_relay_map(struct intel_guc_log *log)
512 {
513 	lockdep_assert_held(&log->relay.lock);
514 
515 	if (!log->vma || !log->buf_addr)
516 		return -ENODEV;
517 
518 	/*
519 	 * WC vmalloc mapping of log buffer pages was done at
520 	 * GuC Log Init time, but lets keep a ref for book-keeping
521 	 */
522 	i915_gem_object_get(log->vma->obj);
523 	log->relay.buf_in_use = true;
524 
525 	return 0;
526 }
527 
528 static void guc_log_relay_unmap(struct intel_guc_log *log)
529 {
530 	lockdep_assert_held(&log->relay.lock);
531 
532 	i915_gem_object_put(log->vma->obj);
533 	log->relay.buf_in_use = false;
534 }
535 
536 void intel_guc_log_init_early(struct intel_guc_log *log)
537 {
538 	mutex_init(&log->relay.lock);
539 	INIT_WORK(&log->relay.flush_work, copy_debug_logs_work);
540 	log->relay.started = false;
541 }
542 
543 static int guc_log_relay_create(struct intel_guc_log *log)
544 {
545 	struct intel_guc *guc = log_to_guc(log);
546 	struct drm_i915_private *dev_priv = guc_to_gt(guc)->i915;
547 	struct rchan *guc_log_relay_chan;
548 	size_t n_subbufs, subbuf_size;
549 	int ret;
550 
551 	lockdep_assert_held(&log->relay.lock);
552 	GEM_BUG_ON(!log->vma);
553 
554 	 /*
555 	  * Keep the size of sub buffers same as shared log buffer
556 	  * but GuC log-events excludes the error-state-capture logs
557 	  */
558 	subbuf_size = log->vma->size - intel_guc_log_section_size_capture(log);
559 
560 	/*
561 	 * Store up to 8 snapshots, which is large enough to buffer sufficient
562 	 * boot time logs and provides enough leeway to User, in terms of
563 	 * latency, for consuming the logs from relay. Also doesn't take
564 	 * up too much memory.
565 	 */
566 	n_subbufs = 8;
567 
568 	guc_log_relay_chan = relay_open("guc_log",
569 					dev_priv->drm.primary->debugfs_root,
570 					subbuf_size, n_subbufs,
571 					&relay_callbacks, dev_priv);
572 	if (!guc_log_relay_chan) {
573 		DRM_ERROR("Couldn't create relay chan for GuC logging\n");
574 
575 		ret = -ENOMEM;
576 		return ret;
577 	}
578 
579 	GEM_BUG_ON(guc_log_relay_chan->subbuf_size < subbuf_size);
580 	log->relay.channel = guc_log_relay_chan;
581 
582 	return 0;
583 }
584 
585 static void guc_log_relay_destroy(struct intel_guc_log *log)
586 {
587 	lockdep_assert_held(&log->relay.lock);
588 
589 	relay_close(log->relay.channel);
590 	log->relay.channel = NULL;
591 }
592 
593 static void guc_log_copy_debuglogs_for_relay(struct intel_guc_log *log)
594 {
595 	struct intel_guc *guc = log_to_guc(log);
596 	struct drm_i915_private *dev_priv = guc_to_gt(guc)->i915;
597 	intel_wakeref_t wakeref;
598 
599 	_guc_log_copy_debuglogs_for_relay(log);
600 
601 	/*
602 	 * Generally device is expected to be active only at this
603 	 * time, so get/put should be really quick.
604 	 */
605 	with_intel_runtime_pm(&dev_priv->runtime_pm, wakeref)
606 		guc_action_flush_log_complete(guc);
607 }
608 
609 static u32 __get_default_log_level(struct intel_guc_log *log)
610 {
611 	struct intel_guc *guc = log_to_guc(log);
612 	struct drm_i915_private *i915 = guc_to_gt(guc)->i915;
613 
614 	/* A negative value means "use platform/config default" */
615 	if (i915->params.guc_log_level < 0) {
616 		return (IS_ENABLED(CONFIG_DRM_I915_DEBUG) ||
617 			IS_ENABLED(CONFIG_DRM_I915_DEBUG_GEM)) ?
618 			GUC_LOG_LEVEL_MAX : GUC_LOG_LEVEL_NON_VERBOSE;
619 	}
620 
621 	if (i915->params.guc_log_level > GUC_LOG_LEVEL_MAX) {
622 		DRM_WARN("Incompatible option detected: %s=%d, %s!\n",
623 			 "guc_log_level", i915->params.guc_log_level,
624 			 "verbosity too high");
625 		return (IS_ENABLED(CONFIG_DRM_I915_DEBUG) ||
626 			IS_ENABLED(CONFIG_DRM_I915_DEBUG_GEM)) ?
627 			GUC_LOG_LEVEL_MAX : GUC_LOG_LEVEL_DISABLED;
628 	}
629 
630 	GEM_BUG_ON(i915->params.guc_log_level < GUC_LOG_LEVEL_DISABLED);
631 	GEM_BUG_ON(i915->params.guc_log_level > GUC_LOG_LEVEL_MAX);
632 	return i915->params.guc_log_level;
633 }
634 
635 int intel_guc_log_create(struct intel_guc_log *log)
636 {
637 	struct intel_guc *guc = log_to_guc(log);
638 	struct i915_vma *vma;
639 	void *vaddr;
640 	u32 guc_log_size;
641 	int ret;
642 
643 	GEM_BUG_ON(log->vma);
644 
645 	guc_log_size = intel_guc_log_size(log);
646 
647 	vma = intel_guc_allocate_vma(guc, guc_log_size);
648 	if (IS_ERR(vma)) {
649 		ret = PTR_ERR(vma);
650 		goto err;
651 	}
652 
653 	log->vma = vma;
654 	/*
655 	 * Create a WC (Uncached for read) vmalloc mapping up front immediate access to
656 	 * data from memory during  critical events such as error capture
657 	 */
658 	vaddr = i915_gem_object_pin_map_unlocked(log->vma->obj, I915_MAP_WC);
659 	if (IS_ERR(vaddr)) {
660 		ret = PTR_ERR(vaddr);
661 		i915_vma_unpin_and_release(&log->vma, 0);
662 		goto err;
663 	}
664 	log->buf_addr = vaddr;
665 
666 	log->level = __get_default_log_level(log);
667 	DRM_DEBUG_DRIVER("guc_log_level=%d (%s, verbose:%s, verbosity:%d)\n",
668 			 log->level, str_enabled_disabled(log->level),
669 			 str_yes_no(GUC_LOG_LEVEL_IS_VERBOSE(log->level)),
670 			 GUC_LOG_LEVEL_TO_VERBOSITY(log->level));
671 
672 	return 0;
673 
674 err:
675 	DRM_ERROR("Failed to allocate or map GuC log buffer. %d\n", ret);
676 	return ret;
677 }
678 
679 void intel_guc_log_destroy(struct intel_guc_log *log)
680 {
681 	log->buf_addr = NULL;
682 	i915_vma_unpin_and_release(&log->vma, I915_VMA_RELEASE_MAP);
683 }
684 
685 int intel_guc_log_set_level(struct intel_guc_log *log, u32 level)
686 {
687 	struct intel_guc *guc = log_to_guc(log);
688 	struct drm_i915_private *dev_priv = guc_to_gt(guc)->i915;
689 	intel_wakeref_t wakeref;
690 	int ret = 0;
691 
692 	BUILD_BUG_ON(GUC_LOG_VERBOSITY_MIN != 0);
693 	GEM_BUG_ON(!log->vma);
694 
695 	/*
696 	 * GuC is recognizing log levels starting from 0 to max, we're using 0
697 	 * as indication that logging should be disabled.
698 	 */
699 	if (level < GUC_LOG_LEVEL_DISABLED || level > GUC_LOG_LEVEL_MAX)
700 		return -EINVAL;
701 
702 	mutex_lock(&dev_priv->drm.struct_mutex);
703 
704 	if (log->level == level)
705 		goto out_unlock;
706 
707 	with_intel_runtime_pm(&dev_priv->runtime_pm, wakeref)
708 		ret = guc_action_control_log(guc,
709 					     GUC_LOG_LEVEL_IS_VERBOSE(level),
710 					     GUC_LOG_LEVEL_IS_ENABLED(level),
711 					     GUC_LOG_LEVEL_TO_VERBOSITY(level));
712 	if (ret) {
713 		DRM_DEBUG_DRIVER("guc_log_control action failed %d\n", ret);
714 		goto out_unlock;
715 	}
716 
717 	log->level = level;
718 
719 out_unlock:
720 	mutex_unlock(&dev_priv->drm.struct_mutex);
721 
722 	return ret;
723 }
724 
725 bool intel_guc_log_relay_created(const struct intel_guc_log *log)
726 {
727 	return log->buf_addr;
728 }
729 
730 int intel_guc_log_relay_open(struct intel_guc_log *log)
731 {
732 	int ret;
733 
734 	if (!log->vma)
735 		return -ENODEV;
736 
737 	mutex_lock(&log->relay.lock);
738 
739 	if (intel_guc_log_relay_created(log)) {
740 		ret = -EEXIST;
741 		goto out_unlock;
742 	}
743 
744 	/*
745 	 * We require SSE 4.1 for fast reads from the GuC log buffer and
746 	 * it should be present on the chipsets supporting GuC based
747 	 * submissions.
748 	 */
749 	if (!i915_has_memcpy_from_wc()) {
750 		ret = -ENXIO;
751 		goto out_unlock;
752 	}
753 
754 	ret = guc_log_relay_create(log);
755 	if (ret)
756 		goto out_unlock;
757 
758 	ret = guc_log_relay_map(log);
759 	if (ret)
760 		goto out_relay;
761 
762 	mutex_unlock(&log->relay.lock);
763 
764 	return 0;
765 
766 out_relay:
767 	guc_log_relay_destroy(log);
768 out_unlock:
769 	mutex_unlock(&log->relay.lock);
770 
771 	return ret;
772 }
773 
774 int intel_guc_log_relay_start(struct intel_guc_log *log)
775 {
776 	if (log->relay.started)
777 		return -EEXIST;
778 
779 	/*
780 	 * When GuC is logging without us relaying to userspace, we're ignoring
781 	 * the flush notification. This means that we need to unconditionally
782 	 * flush on relay enabling, since GuC only notifies us once.
783 	 */
784 	queue_work(system_highpri_wq, &log->relay.flush_work);
785 
786 	log->relay.started = true;
787 
788 	return 0;
789 }
790 
791 void intel_guc_log_relay_flush(struct intel_guc_log *log)
792 {
793 	struct intel_guc *guc = log_to_guc(log);
794 	intel_wakeref_t wakeref;
795 
796 	if (!log->relay.started)
797 		return;
798 
799 	/*
800 	 * Before initiating the forceful flush, wait for any pending/ongoing
801 	 * flush to complete otherwise forceful flush may not actually happen.
802 	 */
803 	flush_work(&log->relay.flush_work);
804 
805 	with_intel_runtime_pm(guc_to_gt(guc)->uncore->rpm, wakeref)
806 		guc_action_flush_log(guc);
807 
808 	/* GuC would have updated log buffer by now, so copy it */
809 	guc_log_copy_debuglogs_for_relay(log);
810 }
811 
812 /*
813  * Stops the relay log. Called from intel_guc_log_relay_close(), so no
814  * possibility of race with start/flush since relay_write cannot race
815  * relay_close.
816  */
817 static void guc_log_relay_stop(struct intel_guc_log *log)
818 {
819 	struct intel_guc *guc = log_to_guc(log);
820 	struct drm_i915_private *i915 = guc_to_gt(guc)->i915;
821 
822 	if (!log->relay.started)
823 		return;
824 
825 	intel_synchronize_irq(i915);
826 
827 	flush_work(&log->relay.flush_work);
828 
829 	log->relay.started = false;
830 }
831 
832 void intel_guc_log_relay_close(struct intel_guc_log *log)
833 {
834 	guc_log_relay_stop(log);
835 
836 	mutex_lock(&log->relay.lock);
837 	GEM_BUG_ON(!intel_guc_log_relay_created(log));
838 	guc_log_relay_unmap(log);
839 	guc_log_relay_destroy(log);
840 	mutex_unlock(&log->relay.lock);
841 }
842 
843 void intel_guc_log_handle_flush_event(struct intel_guc_log *log)
844 {
845 	if (log->relay.started)
846 		queue_work(system_highpri_wq, &log->relay.flush_work);
847 }
848 
849 static const char *
850 stringify_guc_log_type(enum guc_log_buffer_type type)
851 {
852 	switch (type) {
853 	case GUC_DEBUG_LOG_BUFFER:
854 		return "DEBUG";
855 	case GUC_CRASH_DUMP_LOG_BUFFER:
856 		return "CRASH";
857 	case GUC_CAPTURE_LOG_BUFFER:
858 		return "CAPTURE";
859 	default:
860 		MISSING_CASE(type);
861 	}
862 
863 	return "";
864 }
865 
866 /**
867  * intel_guc_log_info - dump information about GuC log relay
868  * @log: the GuC log
869  * @p: the &drm_printer
870  *
871  * Pretty printer for GuC log info
872  */
873 void intel_guc_log_info(struct intel_guc_log *log, struct drm_printer *p)
874 {
875 	enum guc_log_buffer_type type;
876 
877 	if (!intel_guc_log_relay_created(log)) {
878 		drm_puts(p, "GuC log relay not created\n");
879 		return;
880 	}
881 
882 	drm_puts(p, "GuC logging stats:\n");
883 
884 	drm_printf(p, "\tRelay full count: %u\n", log->relay.full_count);
885 
886 	for (type = GUC_DEBUG_LOG_BUFFER; type < GUC_MAX_LOG_BUFFER; type++) {
887 		drm_printf(p, "\t%s:\tflush count %10u, overflow count %10u\n",
888 			   stringify_guc_log_type(type),
889 			   log->stats[type].flush,
890 			   log->stats[type].sampled_overflow);
891 	}
892 }
893 
894 /**
895  * intel_guc_log_dump - dump the contents of the GuC log
896  * @log: the GuC log
897  * @p: the &drm_printer
898  * @dump_load_err: dump the log saved on GuC load error
899  *
900  * Pretty printer for the GuC log
901  */
902 int intel_guc_log_dump(struct intel_guc_log *log, struct drm_printer *p,
903 		       bool dump_load_err)
904 {
905 	struct intel_guc *guc = log_to_guc(log);
906 	struct intel_uc *uc = container_of(guc, struct intel_uc, guc);
907 	struct drm_i915_gem_object *obj = NULL;
908 	void *map;
909 	u32 *page;
910 	int i, j;
911 
912 	if (!intel_guc_is_supported(guc))
913 		return -ENODEV;
914 
915 	if (dump_load_err)
916 		obj = uc->load_err_log;
917 	else if (guc->log.vma)
918 		obj = guc->log.vma->obj;
919 
920 	if (!obj)
921 		return 0;
922 
923 	page = (u32 *)__get_free_page(GFP_KERNEL);
924 	if (!page)
925 		return -ENOMEM;
926 
927 	intel_guc_dump_time_info(guc, p);
928 
929 	map = i915_gem_object_pin_map_unlocked(obj, I915_MAP_WC);
930 	if (IS_ERR(map)) {
931 		DRM_DEBUG("Failed to pin object\n");
932 		drm_puts(p, "(log data unaccessible)\n");
933 		free_page((unsigned long)page);
934 		return PTR_ERR(map);
935 	}
936 
937 	for (i = 0; i < obj->base.size; i += PAGE_SIZE) {
938 		if (!i915_memcpy_from_wc(page, map + i, PAGE_SIZE))
939 			memcpy(page, map + i, PAGE_SIZE);
940 
941 		for (j = 0; j < PAGE_SIZE / sizeof(u32); j += 4)
942 			drm_printf(p, "0x%08x 0x%08x 0x%08x 0x%08x\n",
943 				   *(page + j + 0), *(page + j + 1),
944 				   *(page + j + 2), *(page + j + 3));
945 	}
946 
947 	drm_puts(p, "\n");
948 
949 	i915_gem_object_unpin_map(obj);
950 	free_page((unsigned long)page);
951 
952 	return 0;
953 }
954