xref: /linux/drivers/gpu/drm/i915/gt/uc/intel_guc_log.c (revision 07fdad3a93756b872da7b53647715c48d0f4a2d0)
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 <drm/drm_managed.h>
10 
11 #include "gt/intel_gt.h"
12 #include "i915_drv.h"
13 #include "i915_irq.h"
14 #include "i915_memcpy.h"
15 #include "intel_guc_capture.h"
16 #include "intel_guc_log.h"
17 #include "intel_guc_print.h"
18 
19 #if IS_ENABLED(CONFIG_DRM_I915_DEBUG_GUC)
20 #define GUC_LOG_DEFAULT_CRASH_BUFFER_SIZE	SZ_2M
21 #define GUC_LOG_DEFAULT_DEBUG_BUFFER_SIZE	SZ_16M
22 #define GUC_LOG_DEFAULT_CAPTURE_BUFFER_SIZE	SZ_1M
23 #elif IS_ENABLED(CONFIG_DRM_I915_DEBUG_GEM)
24 #define GUC_LOG_DEFAULT_CRASH_BUFFER_SIZE	SZ_1M
25 #define GUC_LOG_DEFAULT_DEBUG_BUFFER_SIZE	SZ_2M
26 #define GUC_LOG_DEFAULT_CAPTURE_BUFFER_SIZE	SZ_1M
27 #else
28 #define GUC_LOG_DEFAULT_CRASH_BUFFER_SIZE	SZ_8K
29 #define GUC_LOG_DEFAULT_DEBUG_BUFFER_SIZE	SZ_64K
30 #define GUC_LOG_DEFAULT_CAPTURE_BUFFER_SIZE	SZ_1M
31 #endif
32 
33 static void guc_log_copy_debuglogs_for_relay(struct intel_guc_log *log);
34 
35 struct guc_log_section {
36 	u32 max;
37 	u32 flag;
38 	u32 default_val;
39 	const char *name;
40 };
41 
42 static void _guc_log_init_sizes(struct intel_guc_log *log)
43 {
44 	struct intel_guc *guc = log_to_guc(log);
45 	static const struct guc_log_section sections[GUC_LOG_SECTIONS_LIMIT] = {
46 		{
47 			GUC_LOG_CRASH_MASK >> GUC_LOG_CRASH_SHIFT,
48 			GUC_LOG_LOG_ALLOC_UNITS,
49 			GUC_LOG_DEFAULT_CRASH_BUFFER_SIZE,
50 			"crash dump"
51 		},
52 		{
53 			GUC_LOG_DEBUG_MASK >> GUC_LOG_DEBUG_SHIFT,
54 			GUC_LOG_LOG_ALLOC_UNITS,
55 			GUC_LOG_DEFAULT_DEBUG_BUFFER_SIZE,
56 			"debug",
57 		},
58 		{
59 			GUC_LOG_CAPTURE_MASK >> GUC_LOG_CAPTURE_SHIFT,
60 			GUC_LOG_CAPTURE_ALLOC_UNITS,
61 			GUC_LOG_DEFAULT_CAPTURE_BUFFER_SIZE,
62 			"capture",
63 		}
64 	};
65 	int i;
66 
67 	for (i = 0; i < GUC_LOG_SECTIONS_LIMIT; i++)
68 		log->sizes[i].bytes = sections[i].default_val;
69 
70 	/* If debug size > 1MB then bump default crash size to keep the same units */
71 	if (log->sizes[GUC_LOG_SECTIONS_DEBUG].bytes >= SZ_1M &&
72 	    GUC_LOG_DEFAULT_CRASH_BUFFER_SIZE < SZ_1M)
73 		log->sizes[GUC_LOG_SECTIONS_CRASH].bytes = SZ_1M;
74 
75 	/* Prepare the GuC API structure fields: */
76 	for (i = 0; i < GUC_LOG_SECTIONS_LIMIT; i++) {
77 		/* Convert to correct units */
78 		if ((log->sizes[i].bytes % SZ_1M) == 0) {
79 			log->sizes[i].units = SZ_1M;
80 			log->sizes[i].flag = sections[i].flag;
81 		} else {
82 			log->sizes[i].units = SZ_4K;
83 			log->sizes[i].flag = 0;
84 		}
85 
86 		if (!IS_ALIGNED(log->sizes[i].bytes, log->sizes[i].units))
87 			guc_err(guc, "Mis-aligned log %s size: 0x%X vs 0x%X!\n",
88 				sections[i].name, log->sizes[i].bytes, log->sizes[i].units);
89 		log->sizes[i].count = log->sizes[i].bytes / log->sizes[i].units;
90 
91 		if (!log->sizes[i].count) {
92 			guc_err(guc, "Zero log %s size!\n", sections[i].name);
93 		} else {
94 			/* Size is +1 unit */
95 			log->sizes[i].count--;
96 		}
97 
98 		/* Clip to field size */
99 		if (log->sizes[i].count > sections[i].max) {
100 			guc_err(guc, "log %s size too large: %d vs %d!\n",
101 				sections[i].name, log->sizes[i].count + 1, sections[i].max + 1);
102 			log->sizes[i].count = sections[i].max;
103 		}
104 	}
105 
106 	if (log->sizes[GUC_LOG_SECTIONS_CRASH].units != log->sizes[GUC_LOG_SECTIONS_DEBUG].units) {
107 		guc_err(guc, "Unit mismatch for crash and debug sections: %d vs %d!\n",
108 			log->sizes[GUC_LOG_SECTIONS_CRASH].units,
109 			log->sizes[GUC_LOG_SECTIONS_DEBUG].units);
110 		log->sizes[GUC_LOG_SECTIONS_CRASH].units = log->sizes[GUC_LOG_SECTIONS_DEBUG].units;
111 		log->sizes[GUC_LOG_SECTIONS_CRASH].count = 0;
112 	}
113 
114 	log->sizes_initialised = true;
115 }
116 
117 static void guc_log_init_sizes(struct intel_guc_log *log)
118 {
119 	if (log->sizes_initialised)
120 		return;
121 
122 	_guc_log_init_sizes(log);
123 }
124 
125 static u32 intel_guc_log_section_size_crash(struct intel_guc_log *log)
126 {
127 	guc_log_init_sizes(log);
128 
129 	return log->sizes[GUC_LOG_SECTIONS_CRASH].bytes;
130 }
131 
132 static u32 intel_guc_log_section_size_debug(struct intel_guc_log *log)
133 {
134 	guc_log_init_sizes(log);
135 
136 	return log->sizes[GUC_LOG_SECTIONS_DEBUG].bytes;
137 }
138 
139 u32 intel_guc_log_section_size_capture(struct intel_guc_log *log)
140 {
141 	guc_log_init_sizes(log);
142 
143 	return log->sizes[GUC_LOG_SECTIONS_CAPTURE].bytes;
144 }
145 
146 static u32 intel_guc_log_size(struct intel_guc_log *log)
147 {
148 	/*
149 	 *  GuC Log buffer Layout:
150 	 *
151 	 *  NB: Ordering must follow "enum guc_log_buffer_type".
152 	 *
153 	 *  +===============================+ 00B
154 	 *  |      Debug state header       |
155 	 *  +-------------------------------+ 32B
156 	 *  |    Crash dump state header    |
157 	 *  +-------------------------------+ 64B
158 	 *  |     Capture state header      |
159 	 *  +-------------------------------+ 96B
160 	 *  |                               |
161 	 *  +===============================+ PAGE_SIZE (4KB)
162 	 *  |          Debug logs           |
163 	 *  +===============================+ + DEBUG_SIZE
164 	 *  |        Crash Dump logs        |
165 	 *  +===============================+ + CRASH_SIZE
166 	 *  |         Capture logs          |
167 	 *  +===============================+ + CAPTURE_SIZE
168 	 */
169 	return PAGE_SIZE +
170 		intel_guc_log_section_size_crash(log) +
171 		intel_guc_log_section_size_debug(log) +
172 		intel_guc_log_section_size_capture(log);
173 }
174 
175 /**
176  * DOC: GuC firmware log
177  *
178  * Firmware log is enabled by setting i915.guc_log_level to the positive level.
179  * Log data is printed out via reading debugfs i915_guc_log_dump. Reading from
180  * i915_guc_load_status will print out firmware loading status and scratch
181  * registers value.
182  */
183 
184 static int guc_action_flush_log_complete(struct intel_guc *guc)
185 {
186 	u32 action[] = {
187 		INTEL_GUC_ACTION_LOG_BUFFER_FILE_FLUSH_COMPLETE,
188 		GUC_DEBUG_LOG_BUFFER
189 	};
190 
191 	return intel_guc_send_nb(guc, action, ARRAY_SIZE(action), 0);
192 }
193 
194 static int guc_action_flush_log(struct intel_guc *guc)
195 {
196 	u32 action[] = {
197 		INTEL_GUC_ACTION_FORCE_LOG_BUFFER_FLUSH,
198 		0
199 	};
200 
201 	return intel_guc_send(guc, action, ARRAY_SIZE(action));
202 }
203 
204 static int guc_action_control_log(struct intel_guc *guc, bool enable,
205 				  bool default_logging, u32 verbosity)
206 {
207 	u32 action[] = {
208 		INTEL_GUC_ACTION_UK_LOG_ENABLE_LOGGING,
209 		(enable ? GUC_LOG_CONTROL_LOGGING_ENABLED : 0) |
210 		(verbosity << GUC_LOG_CONTROL_VERBOSITY_SHIFT) |
211 		(default_logging ? GUC_LOG_CONTROL_DEFAULT_LOGGING : 0)
212 	};
213 
214 	GEM_BUG_ON(verbosity > GUC_LOG_VERBOSITY_MAX);
215 
216 	return intel_guc_send(guc, action, ARRAY_SIZE(action));
217 }
218 
219 /*
220  * Sub buffer switch callback. Called whenever relay has to switch to a new
221  * sub buffer, relay stays on the same sub buffer if 0 is returned.
222  */
223 static int subbuf_start_callback(struct rchan_buf *buf,
224 				 void *subbuf,
225 				 void *prev_subbuf)
226 {
227 	/*
228 	 * Use no-overwrite mode by default, where relay will stop accepting
229 	 * new data if there are no empty sub buffers left.
230 	 * There is no strict synchronization enforced by relay between Consumer
231 	 * and Producer. In overwrite mode, there is a possibility of getting
232 	 * inconsistent/garbled data, the producer could be writing on to the
233 	 * same sub buffer from which Consumer is reading. This can't be avoided
234 	 * unless Consumer is fast enough and can always run in tandem with
235 	 * Producer.
236 	 */
237 	if (relay_buf_full(buf))
238 		return 0;
239 
240 	return 1;
241 }
242 
243 /*
244  * file_create() callback. Creates relay file in debugfs.
245  */
246 static struct dentry *create_buf_file_callback(const char *filename,
247 					       struct dentry *parent,
248 					       umode_t mode,
249 					       struct rchan_buf *buf,
250 					       int *is_global)
251 {
252 	struct dentry *buf_file;
253 
254 	/*
255 	 * This to enable the use of a single buffer for the relay channel and
256 	 * correspondingly have a single file exposed to User, through which
257 	 * it can collect the logs in order without any post-processing.
258 	 * Need to set 'is_global' even if parent is NULL for early logging.
259 	 */
260 	*is_global = 1;
261 
262 	if (!parent)
263 		return NULL;
264 
265 	buf_file = debugfs_create_file(filename, mode,
266 				       parent, buf, &relay_file_operations);
267 	if (IS_ERR(buf_file))
268 		return NULL;
269 
270 	return buf_file;
271 }
272 
273 /*
274  * file_remove() default callback. Removes relay file in debugfs.
275  */
276 static int remove_buf_file_callback(struct dentry *dentry)
277 {
278 	debugfs_remove(dentry);
279 	return 0;
280 }
281 
282 /* relay channel callbacks */
283 static const struct rchan_callbacks relay_callbacks = {
284 	.subbuf_start = subbuf_start_callback,
285 	.create_buf_file = create_buf_file_callback,
286 	.remove_buf_file = remove_buf_file_callback,
287 };
288 
289 static void guc_move_to_next_buf(struct intel_guc_log *log)
290 {
291 	/*
292 	 * Make sure the updates made in the sub buffer are visible when
293 	 * Consumer sees the following update to offset inside the sub buffer.
294 	 */
295 	smp_wmb();
296 
297 	/* All data has been written, so now move the offset of sub buffer. */
298 	relay_reserve(log->relay.channel, log->vma->obj->base.size -
299 					  intel_guc_log_section_size_capture(log));
300 
301 	/* Switch to the next sub buffer */
302 	relay_flush(log->relay.channel);
303 }
304 
305 static void *guc_get_write_buffer(struct intel_guc_log *log)
306 {
307 	/*
308 	 * Just get the base address of a new sub buffer and copy data into it
309 	 * ourselves. NULL will be returned in no-overwrite mode, if all sub
310 	 * buffers are full. Could have used the relay_write() to indirectly
311 	 * copy the data, but that would have been bit convoluted, as we need to
312 	 * write to only certain locations inside a sub buffer which cannot be
313 	 * done without using relay_reserve() along with relay_write(). So its
314 	 * better to use relay_reserve() alone.
315 	 */
316 	return relay_reserve(log->relay.channel, 0);
317 }
318 
319 bool intel_guc_check_log_buf_overflow(struct intel_guc_log *log,
320 				      enum guc_log_buffer_type type,
321 				      unsigned int full_cnt)
322 {
323 	unsigned int prev_full_cnt = log->stats[type].sampled_overflow;
324 	bool overflow = false;
325 
326 	if (full_cnt != prev_full_cnt) {
327 		overflow = true;
328 
329 		log->stats[type].overflow = full_cnt;
330 		log->stats[type].sampled_overflow += full_cnt - prev_full_cnt;
331 
332 		if (full_cnt < prev_full_cnt) {
333 			/* buffer_full_cnt is a 4 bit counter */
334 			log->stats[type].sampled_overflow += 16;
335 		}
336 
337 		guc_notice_ratelimited(log_to_guc(log), "log buffer overflow\n");
338 	}
339 
340 	return overflow;
341 }
342 
343 unsigned int intel_guc_get_log_buffer_size(struct intel_guc_log *log,
344 					   enum guc_log_buffer_type type)
345 {
346 	switch (type) {
347 	case GUC_DEBUG_LOG_BUFFER:
348 		return intel_guc_log_section_size_debug(log);
349 	case GUC_CRASH_DUMP_LOG_BUFFER:
350 		return intel_guc_log_section_size_crash(log);
351 	case GUC_CAPTURE_LOG_BUFFER:
352 		return intel_guc_log_section_size_capture(log);
353 	default:
354 		MISSING_CASE(type);
355 	}
356 
357 	return 0;
358 }
359 
360 size_t intel_guc_get_log_buffer_offset(struct intel_guc_log *log,
361 				       enum guc_log_buffer_type type)
362 {
363 	enum guc_log_buffer_type i;
364 	size_t offset = PAGE_SIZE;/* for the log_buffer_states */
365 
366 	for (i = GUC_DEBUG_LOG_BUFFER; i < GUC_MAX_LOG_BUFFER; ++i) {
367 		if (i == type)
368 			break;
369 		offset += intel_guc_get_log_buffer_size(log, i);
370 	}
371 
372 	return offset;
373 }
374 
375 static void _guc_log_copy_debuglogs_for_relay(struct intel_guc_log *log)
376 {
377 	struct intel_guc *guc = log_to_guc(log);
378 	unsigned int buffer_size, read_offset, write_offset, bytes_to_copy, full_cnt;
379 	struct guc_log_buffer_state *log_buf_state, *log_buf_snapshot_state;
380 	struct guc_log_buffer_state log_buf_state_local;
381 	enum guc_log_buffer_type type;
382 	void *src_data, *dst_data;
383 	bool new_overflow;
384 
385 	mutex_lock(&log->relay.lock);
386 
387 	if (guc_WARN_ON(guc, !intel_guc_log_relay_created(log)))
388 		goto out_unlock;
389 
390 	/* Get the pointer to shared GuC log buffer */
391 	src_data = log->buf_addr;
392 	log_buf_state = src_data;
393 
394 	/* Get the pointer to local buffer to store the logs */
395 	log_buf_snapshot_state = dst_data = guc_get_write_buffer(log);
396 
397 	if (unlikely(!log_buf_snapshot_state)) {
398 		/*
399 		 * Used rate limited to avoid deluge of messages, logs might be
400 		 * getting consumed by User at a slow rate.
401 		 */
402 		guc_err_ratelimited(guc, "no sub-buffer to copy general logs\n");
403 		log->relay.full_count++;
404 
405 		goto out_unlock;
406 	}
407 
408 	/* Actual logs are present from the 2nd page */
409 	src_data += PAGE_SIZE;
410 	dst_data += PAGE_SIZE;
411 
412 	/* For relay logging, we exclude error state capture */
413 	for (type = GUC_DEBUG_LOG_BUFFER; type <= GUC_CRASH_DUMP_LOG_BUFFER; type++) {
414 		/*
415 		 * Make a copy of the state structure, inside GuC log buffer
416 		 * (which is uncached mapped), on the stack to avoid reading
417 		 * from it multiple times.
418 		 */
419 		memcpy(&log_buf_state_local, log_buf_state,
420 		       sizeof(struct guc_log_buffer_state));
421 		buffer_size = intel_guc_get_log_buffer_size(log, type);
422 		read_offset = log_buf_state_local.read_ptr;
423 		write_offset = log_buf_state_local.sampled_write_ptr;
424 		full_cnt = log_buf_state_local.buffer_full_cnt;
425 
426 		/* Bookkeeping stuff */
427 		log->stats[type].flush += log_buf_state_local.flush_to_file;
428 		new_overflow = intel_guc_check_log_buf_overflow(log, type, full_cnt);
429 
430 		/* Update the state of shared log buffer */
431 		log_buf_state->read_ptr = write_offset;
432 		log_buf_state->flush_to_file = 0;
433 		log_buf_state++;
434 
435 		/* First copy the state structure in snapshot buffer */
436 		memcpy(log_buf_snapshot_state, &log_buf_state_local,
437 		       sizeof(struct guc_log_buffer_state));
438 
439 		/*
440 		 * The write pointer could have been updated by GuC firmware,
441 		 * after sending the flush interrupt to Host, for consistency
442 		 * set write pointer value to same value of sampled_write_ptr
443 		 * in the snapshot buffer.
444 		 */
445 		log_buf_snapshot_state->write_ptr = write_offset;
446 		log_buf_snapshot_state++;
447 
448 		/* Now copy the actual logs. */
449 		if (unlikely(new_overflow)) {
450 			/* copy the whole buffer in case of overflow */
451 			read_offset = 0;
452 			write_offset = buffer_size;
453 		} else if (unlikely((read_offset > buffer_size) ||
454 				    (write_offset > buffer_size))) {
455 			guc_err(guc, "invalid log buffer state\n");
456 			/* copy whole buffer as offsets are unreliable */
457 			read_offset = 0;
458 			write_offset = buffer_size;
459 		}
460 
461 		/* Just copy the newly written data */
462 		if (read_offset > write_offset) {
463 			i915_memcpy_from_wc(dst_data, src_data, write_offset);
464 			bytes_to_copy = buffer_size - read_offset;
465 		} else {
466 			bytes_to_copy = write_offset - read_offset;
467 		}
468 		i915_memcpy_from_wc(dst_data + read_offset,
469 				    src_data + read_offset, bytes_to_copy);
470 
471 		src_data += buffer_size;
472 		dst_data += buffer_size;
473 	}
474 
475 	guc_move_to_next_buf(log);
476 
477 out_unlock:
478 	mutex_unlock(&log->relay.lock);
479 }
480 
481 static void copy_debug_logs_work(struct work_struct *work)
482 {
483 	struct intel_guc_log *log =
484 		container_of(work, struct intel_guc_log, relay.flush_work);
485 
486 	guc_log_copy_debuglogs_for_relay(log);
487 }
488 
489 static int guc_log_relay_map(struct intel_guc_log *log)
490 {
491 	lockdep_assert_held(&log->relay.lock);
492 
493 	if (!log->vma || !log->buf_addr)
494 		return -ENODEV;
495 
496 	/*
497 	 * WC vmalloc mapping of log buffer pages was done at
498 	 * GuC Log Init time, but lets keep a ref for book-keeping
499 	 */
500 	i915_gem_object_get(log->vma->obj);
501 	log->relay.buf_in_use = true;
502 
503 	return 0;
504 }
505 
506 static void guc_log_relay_unmap(struct intel_guc_log *log)
507 {
508 	lockdep_assert_held(&log->relay.lock);
509 
510 	i915_gem_object_put(log->vma->obj);
511 	log->relay.buf_in_use = false;
512 }
513 
514 void intel_guc_log_init_early(struct intel_guc_log *log)
515 {
516 	struct intel_guc *guc = log_to_guc(log);
517 	struct drm_i915_private *i915 = guc_to_i915(guc);
518 
519 	drmm_mutex_init(&i915->drm, &log->relay.lock);
520 	drmm_mutex_init(&i915->drm, &log->guc_lock);
521 	INIT_WORK(&log->relay.flush_work, copy_debug_logs_work);
522 	log->relay.started = false;
523 }
524 
525 static int guc_log_relay_create(struct intel_guc_log *log)
526 {
527 	struct intel_guc *guc = log_to_guc(log);
528 	struct drm_i915_private *i915 = guc_to_i915(guc);
529 	struct rchan *guc_log_relay_chan;
530 	size_t n_subbufs, subbuf_size;
531 	int ret;
532 
533 	lockdep_assert_held(&log->relay.lock);
534 	GEM_BUG_ON(!log->vma);
535 
536 	 /*
537 	  * Keep the size of sub buffers same as shared log buffer
538 	  * but GuC log-events excludes the error-state-capture logs
539 	  */
540 	subbuf_size = log->vma->size - intel_guc_log_section_size_capture(log);
541 
542 	/*
543 	 * Store up to 8 snapshots, which is large enough to buffer sufficient
544 	 * boot time logs and provides enough leeway to User, in terms of
545 	 * latency, for consuming the logs from relay. Also doesn't take
546 	 * up too much memory.
547 	 */
548 	n_subbufs = 8;
549 
550 	if (!guc->dbgfs_node)
551 		return -ENOENT;
552 
553 	guc_log_relay_chan = relay_open("guc_log",
554 					guc->dbgfs_node,
555 					subbuf_size, n_subbufs,
556 					&relay_callbacks, i915);
557 	if (!guc_log_relay_chan) {
558 		guc_err(guc, "Couldn't create relay channel for logging\n");
559 
560 		ret = -ENOMEM;
561 		return ret;
562 	}
563 
564 	GEM_BUG_ON(guc_log_relay_chan->subbuf_size < subbuf_size);
565 	log->relay.channel = guc_log_relay_chan;
566 
567 	return 0;
568 }
569 
570 static void guc_log_relay_destroy(struct intel_guc_log *log)
571 {
572 	lockdep_assert_held(&log->relay.lock);
573 
574 	relay_close(log->relay.channel);
575 	log->relay.channel = NULL;
576 }
577 
578 static void guc_log_copy_debuglogs_for_relay(struct intel_guc_log *log)
579 {
580 	struct intel_guc *guc = log_to_guc(log);
581 	struct drm_i915_private *i915 = guc_to_i915(guc);
582 	intel_wakeref_t wakeref;
583 
584 	_guc_log_copy_debuglogs_for_relay(log);
585 
586 	/*
587 	 * Generally device is expected to be active only at this
588 	 * time, so get/put should be really quick.
589 	 */
590 	with_intel_runtime_pm(&i915->runtime_pm, wakeref)
591 		guc_action_flush_log_complete(guc);
592 }
593 
594 static u32 __get_default_log_level(struct intel_guc_log *log)
595 {
596 	struct intel_guc *guc = log_to_guc(log);
597 	struct drm_i915_private *i915 = guc_to_i915(guc);
598 
599 	/* A negative value means "use platform/config default" */
600 	if (i915->params.guc_log_level < 0) {
601 		return (IS_ENABLED(CONFIG_DRM_I915_DEBUG) ||
602 			IS_ENABLED(CONFIG_DRM_I915_DEBUG_GEM)) ?
603 			GUC_LOG_LEVEL_MAX : GUC_LOG_LEVEL_NON_VERBOSE;
604 	}
605 
606 	if (i915->params.guc_log_level > GUC_LOG_LEVEL_MAX) {
607 		guc_warn(guc, "Log verbosity param out of range: %d > %d!\n",
608 			 i915->params.guc_log_level, GUC_LOG_LEVEL_MAX);
609 		return (IS_ENABLED(CONFIG_DRM_I915_DEBUG) ||
610 			IS_ENABLED(CONFIG_DRM_I915_DEBUG_GEM)) ?
611 			GUC_LOG_LEVEL_MAX : GUC_LOG_LEVEL_DISABLED;
612 	}
613 
614 	GEM_BUG_ON(i915->params.guc_log_level < GUC_LOG_LEVEL_DISABLED);
615 	GEM_BUG_ON(i915->params.guc_log_level > GUC_LOG_LEVEL_MAX);
616 	return i915->params.guc_log_level;
617 }
618 
619 int intel_guc_log_create(struct intel_guc_log *log)
620 {
621 	struct intel_guc *guc = log_to_guc(log);
622 	struct i915_vma *vma;
623 	void *vaddr;
624 	u32 guc_log_size;
625 	int ret;
626 
627 	GEM_BUG_ON(log->vma);
628 
629 	guc_log_size = intel_guc_log_size(log);
630 
631 	vma = intel_guc_allocate_vma(guc, guc_log_size);
632 	if (IS_ERR(vma)) {
633 		ret = PTR_ERR(vma);
634 		goto err;
635 	}
636 
637 	log->vma = vma;
638 	/*
639 	 * Create a WC (Uncached for read) vmalloc mapping up front immediate access to
640 	 * data from memory during  critical events such as error capture
641 	 */
642 	vaddr = i915_gem_object_pin_map_unlocked(log->vma->obj, I915_MAP_WC);
643 	if (IS_ERR(vaddr)) {
644 		ret = PTR_ERR(vaddr);
645 		i915_vma_unpin_and_release(&log->vma, 0);
646 		goto err;
647 	}
648 	log->buf_addr = vaddr;
649 
650 	log->level = __get_default_log_level(log);
651 	guc_dbg(guc, "guc_log_level=%d (%s, verbose:%s, verbosity:%d)\n",
652 		log->level, str_enabled_disabled(log->level),
653 		str_yes_no(GUC_LOG_LEVEL_IS_VERBOSE(log->level)),
654 		GUC_LOG_LEVEL_TO_VERBOSITY(log->level));
655 
656 	return 0;
657 
658 err:
659 	guc_err(guc, "Failed to allocate or map log buffer %pe\n", ERR_PTR(ret));
660 	return ret;
661 }
662 
663 void intel_guc_log_destroy(struct intel_guc_log *log)
664 {
665 	log->buf_addr = NULL;
666 	i915_vma_unpin_and_release(&log->vma, I915_VMA_RELEASE_MAP);
667 }
668 
669 int intel_guc_log_set_level(struct intel_guc_log *log, u32 level)
670 {
671 	struct intel_guc *guc = log_to_guc(log);
672 	struct drm_i915_private *i915 = guc_to_i915(guc);
673 	intel_wakeref_t wakeref;
674 	int ret = 0;
675 
676 	BUILD_BUG_ON(GUC_LOG_VERBOSITY_MIN != 0);
677 	GEM_BUG_ON(!log->vma);
678 
679 	/*
680 	 * GuC is recognizing log levels starting from 0 to max, we're using 0
681 	 * as indication that logging should be disabled.
682 	 */
683 	if (level < GUC_LOG_LEVEL_DISABLED || level > GUC_LOG_LEVEL_MAX)
684 		return -EINVAL;
685 
686 	mutex_lock(&log->guc_lock);
687 
688 	if (log->level == level)
689 		goto out_unlock;
690 
691 	with_intel_runtime_pm(&i915->runtime_pm, wakeref)
692 		ret = guc_action_control_log(guc,
693 					     GUC_LOG_LEVEL_IS_VERBOSE(level),
694 					     GUC_LOG_LEVEL_IS_ENABLED(level),
695 					     GUC_LOG_LEVEL_TO_VERBOSITY(level));
696 	if (ret) {
697 		guc_dbg(guc, "guc_log_control action failed %pe\n", ERR_PTR(ret));
698 		goto out_unlock;
699 	}
700 
701 	log->level = level;
702 
703 out_unlock:
704 	mutex_unlock(&log->guc_lock);
705 
706 	return ret;
707 }
708 
709 bool intel_guc_log_relay_created(const struct intel_guc_log *log)
710 {
711 	return log->buf_addr;
712 }
713 
714 int intel_guc_log_relay_open(struct intel_guc_log *log)
715 {
716 	int ret;
717 
718 	if (!log->vma)
719 		return -ENODEV;
720 
721 	mutex_lock(&log->relay.lock);
722 
723 	if (intel_guc_log_relay_created(log)) {
724 		ret = -EEXIST;
725 		goto out_unlock;
726 	}
727 
728 	/*
729 	 * We require SSE 4.1 for fast reads from the GuC log buffer and
730 	 * it should be present on the chipsets supporting GuC based
731 	 * submissions.
732 	 */
733 	if (!i915_has_memcpy_from_wc()) {
734 		ret = -ENXIO;
735 		goto out_unlock;
736 	}
737 
738 	ret = guc_log_relay_create(log);
739 	if (ret)
740 		goto out_unlock;
741 
742 	ret = guc_log_relay_map(log);
743 	if (ret)
744 		goto out_relay;
745 
746 	mutex_unlock(&log->relay.lock);
747 
748 	return 0;
749 
750 out_relay:
751 	guc_log_relay_destroy(log);
752 out_unlock:
753 	mutex_unlock(&log->relay.lock);
754 
755 	return ret;
756 }
757 
758 int intel_guc_log_relay_start(struct intel_guc_log *log)
759 {
760 	if (log->relay.started)
761 		return -EEXIST;
762 
763 	/*
764 	 * When GuC is logging without us relaying to userspace, we're ignoring
765 	 * the flush notification. This means that we need to unconditionally
766 	 * flush on relay enabling, since GuC only notifies us once.
767 	 */
768 	queue_work(system_highpri_wq, &log->relay.flush_work);
769 
770 	log->relay.started = true;
771 
772 	return 0;
773 }
774 
775 void intel_guc_log_relay_flush(struct intel_guc_log *log)
776 {
777 	struct intel_guc *guc = log_to_guc(log);
778 	intel_wakeref_t wakeref;
779 
780 	if (!log->relay.started)
781 		return;
782 
783 	/*
784 	 * Before initiating the forceful flush, wait for any pending/ongoing
785 	 * flush to complete otherwise forceful flush may not actually happen.
786 	 */
787 	flush_work(&log->relay.flush_work);
788 
789 	with_intel_runtime_pm(guc_to_gt(guc)->uncore->rpm, wakeref)
790 		guc_action_flush_log(guc);
791 
792 	/* GuC would have updated log buffer by now, so copy it */
793 	guc_log_copy_debuglogs_for_relay(log);
794 }
795 
796 /*
797  * Stops the relay log. Called from intel_guc_log_relay_close(), so no
798  * possibility of race with start/flush since relay_write cannot race
799  * relay_close.
800  */
801 static void guc_log_relay_stop(struct intel_guc_log *log)
802 {
803 	struct intel_guc *guc = log_to_guc(log);
804 	struct drm_i915_private *i915 = guc_to_i915(guc);
805 
806 	if (!log->relay.started)
807 		return;
808 
809 	intel_synchronize_irq(i915);
810 
811 	flush_work(&log->relay.flush_work);
812 
813 	log->relay.started = false;
814 }
815 
816 void intel_guc_log_relay_close(struct intel_guc_log *log)
817 {
818 	guc_log_relay_stop(log);
819 
820 	mutex_lock(&log->relay.lock);
821 	GEM_BUG_ON(!intel_guc_log_relay_created(log));
822 	guc_log_relay_unmap(log);
823 	guc_log_relay_destroy(log);
824 	mutex_unlock(&log->relay.lock);
825 }
826 
827 void intel_guc_log_handle_flush_event(struct intel_guc_log *log)
828 {
829 	if (log->relay.started)
830 		queue_work(system_highpri_wq, &log->relay.flush_work);
831 }
832 
833 static const char *
834 stringify_guc_log_type(enum guc_log_buffer_type type)
835 {
836 	switch (type) {
837 	case GUC_DEBUG_LOG_BUFFER:
838 		return "DEBUG";
839 	case GUC_CRASH_DUMP_LOG_BUFFER:
840 		return "CRASH";
841 	case GUC_CAPTURE_LOG_BUFFER:
842 		return "CAPTURE";
843 	default:
844 		MISSING_CASE(type);
845 	}
846 
847 	return "";
848 }
849 
850 /**
851  * intel_guc_log_info - dump information about GuC log relay
852  * @log: the GuC log
853  * @p: the &drm_printer
854  *
855  * Pretty printer for GuC log info
856  */
857 void intel_guc_log_info(struct intel_guc_log *log, struct drm_printer *p)
858 {
859 	enum guc_log_buffer_type type;
860 
861 	if (!intel_guc_log_relay_created(log)) {
862 		drm_puts(p, "GuC log relay not created\n");
863 		return;
864 	}
865 
866 	drm_puts(p, "GuC logging stats:\n");
867 
868 	drm_printf(p, "\tRelay full count: %u\n", log->relay.full_count);
869 
870 	for (type = GUC_DEBUG_LOG_BUFFER; type < GUC_MAX_LOG_BUFFER; type++) {
871 		drm_printf(p, "\t%s:\tflush count %10u, overflow count %10u\n",
872 			   stringify_guc_log_type(type),
873 			   log->stats[type].flush,
874 			   log->stats[type].sampled_overflow);
875 	}
876 }
877 
878 /**
879  * intel_guc_log_dump - dump the contents of the GuC log
880  * @log: the GuC log
881  * @p: the &drm_printer
882  * @dump_load_err: dump the log saved on GuC load error
883  *
884  * Pretty printer for the GuC log
885  */
886 int intel_guc_log_dump(struct intel_guc_log *log, struct drm_printer *p,
887 		       bool dump_load_err)
888 {
889 	struct intel_guc *guc = log_to_guc(log);
890 	struct intel_uc *uc = container_of(guc, struct intel_uc, guc);
891 	struct drm_i915_gem_object *obj = NULL;
892 	void *map;
893 	u32 *page;
894 	int i, j;
895 
896 	if (!intel_guc_is_supported(guc))
897 		return -ENODEV;
898 
899 	if (dump_load_err)
900 		obj = uc->load_err_log;
901 	else if (guc->log.vma)
902 		obj = guc->log.vma->obj;
903 
904 	if (!obj)
905 		return 0;
906 
907 	page = (u32 *)__get_free_page(GFP_KERNEL);
908 	if (!page)
909 		return -ENOMEM;
910 
911 	intel_guc_dump_time_info(guc, p);
912 
913 	map = i915_gem_object_pin_map_unlocked(obj, I915_MAP_WC);
914 	if (IS_ERR(map)) {
915 		guc_dbg(guc, "Failed to pin log object: %pe\n", map);
916 		drm_puts(p, "(log data unaccessible)\n");
917 		free_page((unsigned long)page);
918 		return PTR_ERR(map);
919 	}
920 
921 	for (i = 0; i < obj->base.size; i += PAGE_SIZE) {
922 		if (!i915_memcpy_from_wc(page, map + i, PAGE_SIZE))
923 			memcpy(page, map + i, PAGE_SIZE);
924 
925 		for (j = 0; j < PAGE_SIZE / sizeof(u32); j += 4)
926 			drm_printf(p, "0x%08x 0x%08x 0x%08x 0x%08x\n",
927 				   *(page + j + 0), *(page + j + 1),
928 				   *(page + j + 2), *(page + j + 3));
929 	}
930 
931 	drm_puts(p, "\n");
932 
933 	i915_gem_object_unpin_map(obj);
934 	free_page((unsigned long)page);
935 
936 	return 0;
937 }
938