1 /*
2  * Copyright (c) 2008 Intel Corporation
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a
5  * copy of this software and associated documentation files (the "Software"),
6  * to deal in the Software without restriction, including without limitation
7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8  * and/or sell copies of the Software, and to permit persons to whom the
9  * Software is furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice (including the next
12  * paragraph) shall be included in all copies or substantial portions of the
13  * Software.
14  *
15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
21  * IN THE SOFTWARE.
22  *
23  * Authors:
24  *    Eric Anholt <eric@anholt.net>
25  *    Keith Packard <keithp@keithp.com>
26  *    Mika Kuoppala <mika.kuoppala@intel.com>
27  *
28  */
29 
30 #include <linux/ascii85.h>
31 #include <linux/nmi.h>
32 #include <linux/scatterlist.h>
33 #include <linux/stop_machine.h>
34 #include <linux/utsname.h>
35 #include <linux/zlib.h>
36 
37 #include <drm/drm_print.h>
38 
39 #include "i915_gpu_error.h"
40 #include "i915_drv.h"
41 
42 static inline const struct intel_engine_cs *
43 engine_lookup(const struct drm_i915_private *i915, unsigned int id)
44 {
45 	if (id >= I915_NUM_ENGINES)
46 		return NULL;
47 
48 	return i915->engine[id];
49 }
50 
51 static inline const char *
52 __engine_name(const struct intel_engine_cs *engine)
53 {
54 	return engine ? engine->name : "";
55 }
56 
57 static const char *
58 engine_name(const struct drm_i915_private *i915, unsigned int id)
59 {
60 	return __engine_name(engine_lookup(i915, id));
61 }
62 
63 static const char *tiling_flag(int tiling)
64 {
65 	switch (tiling) {
66 	default:
67 	case I915_TILING_NONE: return "";
68 	case I915_TILING_X: return " X";
69 	case I915_TILING_Y: return " Y";
70 	}
71 }
72 
73 static const char *dirty_flag(int dirty)
74 {
75 	return dirty ? " dirty" : "";
76 }
77 
78 static const char *purgeable_flag(int purgeable)
79 {
80 	return purgeable ? " purgeable" : "";
81 }
82 
83 static void __sg_set_buf(struct scatterlist *sg,
84 			 void *addr, unsigned int len, loff_t it)
85 {
86 	sg->page_link = (unsigned long)virt_to_page(addr);
87 	sg->offset = offset_in_page(addr);
88 	sg->length = len;
89 	sg->dma_address = it;
90 }
91 
92 static bool __i915_error_grow(struct drm_i915_error_state_buf *e, size_t len)
93 {
94 	if (!len)
95 		return false;
96 
97 	if (e->bytes + len + 1 <= e->size)
98 		return true;
99 
100 	if (e->bytes) {
101 		__sg_set_buf(e->cur++, e->buf, e->bytes, e->iter);
102 		e->iter += e->bytes;
103 		e->buf = NULL;
104 		e->bytes = 0;
105 	}
106 
107 	if (e->cur == e->end) {
108 		struct scatterlist *sgl;
109 
110 		sgl = (typeof(sgl))__get_free_page(GFP_KERNEL);
111 		if (!sgl) {
112 			e->err = -ENOMEM;
113 			return false;
114 		}
115 
116 		if (e->cur) {
117 			e->cur->offset = 0;
118 			e->cur->length = 0;
119 			e->cur->page_link =
120 				(unsigned long)sgl | SG_CHAIN;
121 		} else {
122 			e->sgl = sgl;
123 		}
124 
125 		e->cur = sgl;
126 		e->end = sgl + SG_MAX_SINGLE_ALLOC - 1;
127 	}
128 
129 	e->size = ALIGN(len + 1, SZ_64K);
130 	e->buf = kmalloc(e->size, GFP_KERNEL | __GFP_NOWARN | __GFP_NORETRY);
131 	if (!e->buf) {
132 		e->size = PAGE_ALIGN(len + 1);
133 		e->buf = kmalloc(e->size, GFP_KERNEL);
134 	}
135 	if (!e->buf) {
136 		e->err = -ENOMEM;
137 		return false;
138 	}
139 
140 	return true;
141 }
142 
143 __printf(2, 0)
144 static void i915_error_vprintf(struct drm_i915_error_state_buf *e,
145 			       const char *fmt, va_list args)
146 {
147 	va_list ap;
148 	int len;
149 
150 	if (e->err)
151 		return;
152 
153 	va_copy(ap, args);
154 	len = vsnprintf(NULL, 0, fmt, ap);
155 	va_end(ap);
156 	if (len <= 0) {
157 		e->err = len;
158 		return;
159 	}
160 
161 	if (!__i915_error_grow(e, len))
162 		return;
163 
164 	GEM_BUG_ON(e->bytes >= e->size);
165 	len = vscnprintf(e->buf + e->bytes, e->size - e->bytes, fmt, args);
166 	if (len < 0) {
167 		e->err = len;
168 		return;
169 	}
170 	e->bytes += len;
171 }
172 
173 static void i915_error_puts(struct drm_i915_error_state_buf *e, const char *str)
174 {
175 	unsigned len;
176 
177 	if (e->err || !str)
178 		return;
179 
180 	len = strlen(str);
181 	if (!__i915_error_grow(e, len))
182 		return;
183 
184 	GEM_BUG_ON(e->bytes + len > e->size);
185 	memcpy(e->buf + e->bytes, str, len);
186 	e->bytes += len;
187 }
188 
189 #define err_printf(e, ...) i915_error_printf(e, __VA_ARGS__)
190 #define err_puts(e, s) i915_error_puts(e, s)
191 
192 static void __i915_printfn_error(struct drm_printer *p, struct va_format *vaf)
193 {
194 	i915_error_vprintf(p->arg, vaf->fmt, *vaf->va);
195 }
196 
197 static inline struct drm_printer
198 i915_error_printer(struct drm_i915_error_state_buf *e)
199 {
200 	struct drm_printer p = {
201 		.printfn = __i915_printfn_error,
202 		.arg = e,
203 	};
204 	return p;
205 }
206 
207 #ifdef CONFIG_DRM_I915_COMPRESS_ERROR
208 
209 struct compress {
210 	struct z_stream_s zstream;
211 	void *tmp;
212 };
213 
214 static bool compress_init(struct compress *c)
215 {
216 	struct z_stream_s *zstream = memset(&c->zstream, 0, sizeof(c->zstream));
217 
218 	zstream->workspace =
219 		kmalloc(zlib_deflate_workspacesize(MAX_WBITS, MAX_MEM_LEVEL),
220 			GFP_ATOMIC | __GFP_NOWARN);
221 	if (!zstream->workspace)
222 		return false;
223 
224 	if (zlib_deflateInit(zstream, Z_DEFAULT_COMPRESSION) != Z_OK) {
225 		kfree(zstream->workspace);
226 		return false;
227 	}
228 
229 	c->tmp = NULL;
230 	if (i915_has_memcpy_from_wc())
231 		c->tmp = (void *)__get_free_page(GFP_ATOMIC | __GFP_NOWARN);
232 
233 	return true;
234 }
235 
236 static void *compress_next_page(struct drm_i915_error_object *dst)
237 {
238 	unsigned long page;
239 
240 	if (dst->page_count >= dst->num_pages)
241 		return ERR_PTR(-ENOSPC);
242 
243 	page = __get_free_page(GFP_ATOMIC | __GFP_NOWARN);
244 	if (!page)
245 		return ERR_PTR(-ENOMEM);
246 
247 	return dst->pages[dst->page_count++] = (void *)page;
248 }
249 
250 static int compress_page(struct compress *c,
251 			 void *src,
252 			 struct drm_i915_error_object *dst)
253 {
254 	struct z_stream_s *zstream = &c->zstream;
255 
256 	zstream->next_in = src;
257 	if (c->tmp && i915_memcpy_from_wc(c->tmp, src, PAGE_SIZE))
258 		zstream->next_in = c->tmp;
259 	zstream->avail_in = PAGE_SIZE;
260 
261 	do {
262 		if (zstream->avail_out == 0) {
263 			zstream->next_out = compress_next_page(dst);
264 			if (IS_ERR(zstream->next_out))
265 				return PTR_ERR(zstream->next_out);
266 
267 			zstream->avail_out = PAGE_SIZE;
268 		}
269 
270 		if (zlib_deflate(zstream, Z_NO_FLUSH) != Z_OK)
271 			return -EIO;
272 
273 		touch_nmi_watchdog();
274 	} while (zstream->avail_in);
275 
276 	/* Fallback to uncompressed if we increase size? */
277 	if (0 && zstream->total_out > zstream->total_in)
278 		return -E2BIG;
279 
280 	return 0;
281 }
282 
283 static int compress_flush(struct compress *c,
284 			  struct drm_i915_error_object *dst)
285 {
286 	struct z_stream_s *zstream = &c->zstream;
287 
288 	do {
289 		switch (zlib_deflate(zstream, Z_FINISH)) {
290 		case Z_OK: /* more space requested */
291 			zstream->next_out = compress_next_page(dst);
292 			if (IS_ERR(zstream->next_out))
293 				return PTR_ERR(zstream->next_out);
294 
295 			zstream->avail_out = PAGE_SIZE;
296 			break;
297 
298 		case Z_STREAM_END:
299 			goto end;
300 
301 		default: /* any error */
302 			return -EIO;
303 		}
304 	} while (1);
305 
306 end:
307 	memset(zstream->next_out, 0, zstream->avail_out);
308 	dst->unused = zstream->avail_out;
309 	return 0;
310 }
311 
312 static void compress_fini(struct compress *c,
313 			  struct drm_i915_error_object *dst)
314 {
315 	struct z_stream_s *zstream = &c->zstream;
316 
317 	zlib_deflateEnd(zstream);
318 	kfree(zstream->workspace);
319 	if (c->tmp)
320 		free_page((unsigned long)c->tmp);
321 }
322 
323 static void err_compression_marker(struct drm_i915_error_state_buf *m)
324 {
325 	err_puts(m, ":");
326 }
327 
328 #else
329 
330 struct compress {
331 };
332 
333 static bool compress_init(struct compress *c)
334 {
335 	return true;
336 }
337 
338 static int compress_page(struct compress *c,
339 			 void *src,
340 			 struct drm_i915_error_object *dst)
341 {
342 	unsigned long page;
343 	void *ptr;
344 
345 	page = __get_free_page(GFP_ATOMIC | __GFP_NOWARN);
346 	if (!page)
347 		return -ENOMEM;
348 
349 	ptr = (void *)page;
350 	if (!i915_memcpy_from_wc(ptr, src, PAGE_SIZE))
351 		memcpy(ptr, src, PAGE_SIZE);
352 	dst->pages[dst->page_count++] = ptr;
353 
354 	return 0;
355 }
356 
357 static int compress_flush(struct compress *c,
358 			  struct drm_i915_error_object *dst)
359 {
360 	return 0;
361 }
362 
363 static void compress_fini(struct compress *c,
364 			  struct drm_i915_error_object *dst)
365 {
366 }
367 
368 static void err_compression_marker(struct drm_i915_error_state_buf *m)
369 {
370 	err_puts(m, "~");
371 }
372 
373 #endif
374 
375 static void print_error_buffers(struct drm_i915_error_state_buf *m,
376 				const char *name,
377 				struct drm_i915_error_buffer *err,
378 				int count)
379 {
380 	err_printf(m, "%s [%d]:\n", name, count);
381 
382 	while (count--) {
383 		err_printf(m, "    %08x_%08x %8u %02x %02x",
384 			   upper_32_bits(err->gtt_offset),
385 			   lower_32_bits(err->gtt_offset),
386 			   err->size,
387 			   err->read_domains,
388 			   err->write_domain);
389 		err_puts(m, tiling_flag(err->tiling));
390 		err_puts(m, dirty_flag(err->dirty));
391 		err_puts(m, purgeable_flag(err->purgeable));
392 		err_puts(m, err->userptr ? " userptr" : "");
393 		err_puts(m, i915_cache_level_str(m->i915, err->cache_level));
394 
395 		if (err->name)
396 			err_printf(m, " (name: %d)", err->name);
397 		if (err->fence_reg != I915_FENCE_REG_NONE)
398 			err_printf(m, " (fence: %d)", err->fence_reg);
399 
400 		err_puts(m, "\n");
401 		err++;
402 	}
403 }
404 
405 static void error_print_instdone(struct drm_i915_error_state_buf *m,
406 				 const struct drm_i915_error_engine *ee)
407 {
408 	int slice;
409 	int subslice;
410 
411 	err_printf(m, "  INSTDONE: 0x%08x\n",
412 		   ee->instdone.instdone);
413 
414 	if (ee->engine_id != RCS0 || INTEL_GEN(m->i915) <= 3)
415 		return;
416 
417 	err_printf(m, "  SC_INSTDONE: 0x%08x\n",
418 		   ee->instdone.slice_common);
419 
420 	if (INTEL_GEN(m->i915) <= 6)
421 		return;
422 
423 	for_each_instdone_slice_subslice(m->i915, slice, subslice)
424 		err_printf(m, "  SAMPLER_INSTDONE[%d][%d]: 0x%08x\n",
425 			   slice, subslice,
426 			   ee->instdone.sampler[slice][subslice]);
427 
428 	for_each_instdone_slice_subslice(m->i915, slice, subslice)
429 		err_printf(m, "  ROW_INSTDONE[%d][%d]: 0x%08x\n",
430 			   slice, subslice,
431 			   ee->instdone.row[slice][subslice]);
432 }
433 
434 static void error_print_request(struct drm_i915_error_state_buf *m,
435 				const char *prefix,
436 				const struct drm_i915_error_request *erq,
437 				const unsigned long epoch)
438 {
439 	if (!erq->seqno)
440 		return;
441 
442 	err_printf(m, "%s pid %d, seqno %8x:%08x%s%s, prio %d, emitted %dms, start %08x, head %08x, tail %08x\n",
443 		   prefix, erq->pid, erq->context, erq->seqno,
444 		   test_bit(DMA_FENCE_FLAG_SIGNALED_BIT,
445 			    &erq->flags) ? "!" : "",
446 		   test_bit(DMA_FENCE_FLAG_ENABLE_SIGNAL_BIT,
447 			    &erq->flags) ? "+" : "",
448 		   erq->sched_attr.priority,
449 		   jiffies_to_msecs(erq->jiffies - epoch),
450 		   erq->start, erq->head, erq->tail);
451 }
452 
453 static void error_print_context(struct drm_i915_error_state_buf *m,
454 				const char *header,
455 				const struct drm_i915_error_context *ctx)
456 {
457 	err_printf(m, "%s%s[%d] hw_id %d, prio %d, guilty %d active %d\n",
458 		   header, ctx->comm, ctx->pid, ctx->hw_id,
459 		   ctx->sched_attr.priority, ctx->guilty, ctx->active);
460 }
461 
462 static void error_print_engine(struct drm_i915_error_state_buf *m,
463 			       const struct drm_i915_error_engine *ee,
464 			       const unsigned long epoch)
465 {
466 	int n;
467 
468 	err_printf(m, "%s command stream:\n",
469 		   engine_name(m->i915, ee->engine_id));
470 	err_printf(m, "  IDLE?: %s\n", yesno(ee->idle));
471 	err_printf(m, "  START: 0x%08x\n", ee->start);
472 	err_printf(m, "  HEAD:  0x%08x [0x%08x]\n", ee->head, ee->rq_head);
473 	err_printf(m, "  TAIL:  0x%08x [0x%08x, 0x%08x]\n",
474 		   ee->tail, ee->rq_post, ee->rq_tail);
475 	err_printf(m, "  CTL:   0x%08x\n", ee->ctl);
476 	err_printf(m, "  MODE:  0x%08x\n", ee->mode);
477 	err_printf(m, "  HWS:   0x%08x\n", ee->hws);
478 	err_printf(m, "  ACTHD: 0x%08x %08x\n",
479 		   (u32)(ee->acthd>>32), (u32)ee->acthd);
480 	err_printf(m, "  IPEIR: 0x%08x\n", ee->ipeir);
481 	err_printf(m, "  IPEHR: 0x%08x\n", ee->ipehr);
482 
483 	error_print_instdone(m, ee);
484 
485 	if (ee->batchbuffer) {
486 		u64 start = ee->batchbuffer->gtt_offset;
487 		u64 end = start + ee->batchbuffer->gtt_size;
488 
489 		err_printf(m, "  batch: [0x%08x_%08x, 0x%08x_%08x]\n",
490 			   upper_32_bits(start), lower_32_bits(start),
491 			   upper_32_bits(end), lower_32_bits(end));
492 	}
493 	if (INTEL_GEN(m->i915) >= 4) {
494 		err_printf(m, "  BBADDR: 0x%08x_%08x\n",
495 			   (u32)(ee->bbaddr>>32), (u32)ee->bbaddr);
496 		err_printf(m, "  BB_STATE: 0x%08x\n", ee->bbstate);
497 		err_printf(m, "  INSTPS: 0x%08x\n", ee->instps);
498 	}
499 	err_printf(m, "  INSTPM: 0x%08x\n", ee->instpm);
500 	err_printf(m, "  FADDR: 0x%08x %08x\n", upper_32_bits(ee->faddr),
501 		   lower_32_bits(ee->faddr));
502 	if (INTEL_GEN(m->i915) >= 6) {
503 		err_printf(m, "  RC PSMI: 0x%08x\n", ee->rc_psmi);
504 		err_printf(m, "  FAULT_REG: 0x%08x\n", ee->fault_reg);
505 	}
506 	if (HAS_PPGTT(m->i915)) {
507 		err_printf(m, "  GFX_MODE: 0x%08x\n", ee->vm_info.gfx_mode);
508 
509 		if (INTEL_GEN(m->i915) >= 8) {
510 			int i;
511 			for (i = 0; i < 4; i++)
512 				err_printf(m, "  PDP%d: 0x%016llx\n",
513 					   i, ee->vm_info.pdp[i]);
514 		} else {
515 			err_printf(m, "  PP_DIR_BASE: 0x%08x\n",
516 				   ee->vm_info.pp_dir_base);
517 		}
518 	}
519 	err_printf(m, "  ring->head: 0x%08x\n", ee->cpu_ring_head);
520 	err_printf(m, "  ring->tail: 0x%08x\n", ee->cpu_ring_tail);
521 	err_printf(m, "  hangcheck timestamp: %dms (%lu%s)\n",
522 		   jiffies_to_msecs(ee->hangcheck_timestamp - epoch),
523 		   ee->hangcheck_timestamp,
524 		   ee->hangcheck_timestamp == epoch ? "; epoch" : "");
525 	err_printf(m, "  engine reset count: %u\n", ee->reset_count);
526 
527 	for (n = 0; n < ee->num_ports; n++) {
528 		err_printf(m, "  ELSP[%d]:", n);
529 		error_print_request(m, " ", &ee->execlist[n], epoch);
530 	}
531 
532 	error_print_context(m, "  Active context: ", &ee->context);
533 }
534 
535 void i915_error_printf(struct drm_i915_error_state_buf *e, const char *f, ...)
536 {
537 	va_list args;
538 
539 	va_start(args, f);
540 	i915_error_vprintf(e, f, args);
541 	va_end(args);
542 }
543 
544 static void print_error_obj(struct drm_i915_error_state_buf *m,
545 			    struct intel_engine_cs *engine,
546 			    const char *name,
547 			    struct drm_i915_error_object *obj)
548 {
549 	char out[ASCII85_BUFSZ];
550 	int page;
551 
552 	if (!obj)
553 		return;
554 
555 	if (name) {
556 		err_printf(m, "%s --- %s = 0x%08x %08x\n",
557 			   engine ? engine->name : "global", name,
558 			   upper_32_bits(obj->gtt_offset),
559 			   lower_32_bits(obj->gtt_offset));
560 	}
561 
562 	err_compression_marker(m);
563 	for (page = 0; page < obj->page_count; page++) {
564 		int i, len;
565 
566 		len = PAGE_SIZE;
567 		if (page == obj->page_count - 1)
568 			len -= obj->unused;
569 		len = ascii85_encode_len(len);
570 
571 		for (i = 0; i < len; i++)
572 			err_puts(m, ascii85_encode(obj->pages[page][i], out));
573 	}
574 	err_puts(m, "\n");
575 }
576 
577 static void err_print_capabilities(struct drm_i915_error_state_buf *m,
578 				   const struct intel_device_info *info,
579 				   const struct intel_runtime_info *runtime,
580 				   const struct intel_driver_caps *caps)
581 {
582 	struct drm_printer p = i915_error_printer(m);
583 
584 	intel_device_info_dump_flags(info, &p);
585 	intel_driver_caps_print(caps, &p);
586 	intel_device_info_dump_topology(&runtime->sseu, &p);
587 }
588 
589 static void err_print_params(struct drm_i915_error_state_buf *m,
590 			     const struct i915_params *params)
591 {
592 	struct drm_printer p = i915_error_printer(m);
593 
594 	i915_params_dump(params, &p);
595 }
596 
597 static void err_print_pciid(struct drm_i915_error_state_buf *m,
598 			    struct drm_i915_private *i915)
599 {
600 	struct pci_dev *pdev = i915->drm.pdev;
601 
602 	err_printf(m, "PCI ID: 0x%04x\n", pdev->device);
603 	err_printf(m, "PCI Revision: 0x%02x\n", pdev->revision);
604 	err_printf(m, "PCI Subsystem: %04x:%04x\n",
605 		   pdev->subsystem_vendor,
606 		   pdev->subsystem_device);
607 }
608 
609 static void err_print_uc(struct drm_i915_error_state_buf *m,
610 			 const struct i915_error_uc *error_uc)
611 {
612 	struct drm_printer p = i915_error_printer(m);
613 	const struct i915_gpu_state *error =
614 		container_of(error_uc, typeof(*error), uc);
615 
616 	if (!error->device_info.has_guc)
617 		return;
618 
619 	intel_uc_fw_dump(&error_uc->guc_fw, &p);
620 	intel_uc_fw_dump(&error_uc->huc_fw, &p);
621 	print_error_obj(m, NULL, "GuC log buffer", error_uc->guc_log);
622 }
623 
624 static void err_free_sgl(struct scatterlist *sgl)
625 {
626 	while (sgl) {
627 		struct scatterlist *sg;
628 
629 		for (sg = sgl; !sg_is_chain(sg); sg++) {
630 			kfree(sg_virt(sg));
631 			if (sg_is_last(sg))
632 				break;
633 		}
634 
635 		sg = sg_is_last(sg) ? NULL : sg_chain_ptr(sg);
636 		free_page((unsigned long)sgl);
637 		sgl = sg;
638 	}
639 }
640 
641 static void __err_print_to_sgl(struct drm_i915_error_state_buf *m,
642 			       struct i915_gpu_state *error)
643 {
644 	struct drm_i915_error_object *obj;
645 	struct timespec64 ts;
646 	int i, j;
647 
648 	if (*error->error_msg)
649 		err_printf(m, "%s\n", error->error_msg);
650 	err_printf(m, "Kernel: %s %s\n",
651 		   init_utsname()->release,
652 		   init_utsname()->machine);
653 	ts = ktime_to_timespec64(error->time);
654 	err_printf(m, "Time: %lld s %ld us\n",
655 		   (s64)ts.tv_sec, ts.tv_nsec / NSEC_PER_USEC);
656 	ts = ktime_to_timespec64(error->boottime);
657 	err_printf(m, "Boottime: %lld s %ld us\n",
658 		   (s64)ts.tv_sec, ts.tv_nsec / NSEC_PER_USEC);
659 	ts = ktime_to_timespec64(error->uptime);
660 	err_printf(m, "Uptime: %lld s %ld us\n",
661 		   (s64)ts.tv_sec, ts.tv_nsec / NSEC_PER_USEC);
662 	err_printf(m, "Epoch: %lu jiffies (%u HZ)\n", error->epoch, HZ);
663 	err_printf(m, "Capture: %lu jiffies; %d ms ago, %d ms after epoch\n",
664 		   error->capture,
665 		   jiffies_to_msecs(jiffies - error->capture),
666 		   jiffies_to_msecs(error->capture - error->epoch));
667 
668 	for (i = 0; i < ARRAY_SIZE(error->engine); i++) {
669 		if (!error->engine[i].context.pid)
670 			continue;
671 
672 		err_printf(m, "Active process (on ring %s): %s [%d]\n",
673 			   engine_name(m->i915, i),
674 			   error->engine[i].context.comm,
675 			   error->engine[i].context.pid);
676 	}
677 	err_printf(m, "Reset count: %u\n", error->reset_count);
678 	err_printf(m, "Suspend count: %u\n", error->suspend_count);
679 	err_printf(m, "Platform: %s\n", intel_platform_name(error->device_info.platform));
680 	err_printf(m, "Subplatform: 0x%x\n",
681 		   intel_subplatform(&error->runtime_info,
682 				     error->device_info.platform));
683 	err_print_pciid(m, m->i915);
684 
685 	err_printf(m, "IOMMU enabled?: %d\n", error->iommu);
686 
687 	if (HAS_CSR(m->i915)) {
688 		struct intel_csr *csr = &m->i915->csr;
689 
690 		err_printf(m, "DMC loaded: %s\n",
691 			   yesno(csr->dmc_payload != NULL));
692 		err_printf(m, "DMC fw version: %d.%d\n",
693 			   CSR_VERSION_MAJOR(csr->version),
694 			   CSR_VERSION_MINOR(csr->version));
695 	}
696 
697 	err_printf(m, "GT awake: %s\n", yesno(error->awake));
698 	err_printf(m, "RPM wakelock: %s\n", yesno(error->wakelock));
699 	err_printf(m, "PM suspended: %s\n", yesno(error->suspended));
700 	err_printf(m, "EIR: 0x%08x\n", error->eir);
701 	err_printf(m, "IER: 0x%08x\n", error->ier);
702 	for (i = 0; i < error->ngtier; i++)
703 		err_printf(m, "GTIER[%d]: 0x%08x\n", i, error->gtier[i]);
704 	err_printf(m, "PGTBL_ER: 0x%08x\n", error->pgtbl_er);
705 	err_printf(m, "FORCEWAKE: 0x%08x\n", error->forcewake);
706 	err_printf(m, "DERRMR: 0x%08x\n", error->derrmr);
707 	err_printf(m, "CCID: 0x%08x\n", error->ccid);
708 
709 	for (i = 0; i < error->nfence; i++)
710 		err_printf(m, "  fence[%d] = %08llx\n", i, error->fence[i]);
711 
712 	if (INTEL_GEN(m->i915) >= 6) {
713 		err_printf(m, "ERROR: 0x%08x\n", error->error);
714 
715 		if (INTEL_GEN(m->i915) >= 8)
716 			err_printf(m, "FAULT_TLB_DATA: 0x%08x 0x%08x\n",
717 				   error->fault_data1, error->fault_data0);
718 
719 		err_printf(m, "DONE_REG: 0x%08x\n", error->done_reg);
720 	}
721 
722 	if (IS_GEN(m->i915, 7))
723 		err_printf(m, "ERR_INT: 0x%08x\n", error->err_int);
724 
725 	for (i = 0; i < ARRAY_SIZE(error->engine); i++) {
726 		if (error->engine[i].engine_id != -1)
727 			error_print_engine(m, &error->engine[i], error->epoch);
728 	}
729 
730 	for (i = 0; i < ARRAY_SIZE(error->active_vm); i++) {
731 		char buf[128];
732 		int len, first = 1;
733 
734 		if (!error->active_vm[i])
735 			break;
736 
737 		len = scnprintf(buf, sizeof(buf), "Active (");
738 		for (j = 0; j < ARRAY_SIZE(error->engine); j++) {
739 			if (error->engine[j].vm != error->active_vm[i])
740 				continue;
741 
742 			len += scnprintf(buf + len, sizeof(buf), "%s%s",
743 					 first ? "" : ", ",
744 					 m->i915->engine[j]->name);
745 			first = 0;
746 		}
747 		scnprintf(buf + len, sizeof(buf), ")");
748 		print_error_buffers(m, buf,
749 				    error->active_bo[i],
750 				    error->active_bo_count[i]);
751 	}
752 
753 	print_error_buffers(m, "Pinned (global)",
754 			    error->pinned_bo,
755 			    error->pinned_bo_count);
756 
757 	for (i = 0; i < ARRAY_SIZE(error->engine); i++) {
758 		const struct drm_i915_error_engine *ee = &error->engine[i];
759 
760 		obj = ee->batchbuffer;
761 		if (obj) {
762 			err_puts(m, m->i915->engine[i]->name);
763 			if (ee->context.pid)
764 				err_printf(m, " (submitted by %s [%d])",
765 					   ee->context.comm,
766 					   ee->context.pid);
767 			err_printf(m, " --- gtt_offset = 0x%08x %08x\n",
768 				   upper_32_bits(obj->gtt_offset),
769 				   lower_32_bits(obj->gtt_offset));
770 			print_error_obj(m, m->i915->engine[i], NULL, obj);
771 		}
772 
773 		for (j = 0; j < ee->user_bo_count; j++)
774 			print_error_obj(m, m->i915->engine[i],
775 					"user", ee->user_bo[j]);
776 
777 		if (ee->num_requests) {
778 			err_printf(m, "%s --- %d requests\n",
779 				   m->i915->engine[i]->name,
780 				   ee->num_requests);
781 			for (j = 0; j < ee->num_requests; j++)
782 				error_print_request(m, " ",
783 						    &ee->requests[j],
784 						    error->epoch);
785 		}
786 
787 		print_error_obj(m, m->i915->engine[i],
788 				"ringbuffer", ee->ringbuffer);
789 
790 		print_error_obj(m, m->i915->engine[i],
791 				"HW Status", ee->hws_page);
792 
793 		print_error_obj(m, m->i915->engine[i],
794 				"HW context", ee->ctx);
795 
796 		print_error_obj(m, m->i915->engine[i],
797 				"WA context", ee->wa_ctx);
798 
799 		print_error_obj(m, m->i915->engine[i],
800 				"WA batchbuffer", ee->wa_batchbuffer);
801 
802 		print_error_obj(m, m->i915->engine[i],
803 				"NULL context", ee->default_state);
804 	}
805 
806 	if (error->overlay)
807 		intel_overlay_print_error_state(m, error->overlay);
808 
809 	if (error->display)
810 		intel_display_print_error_state(m, error->display);
811 
812 	err_print_capabilities(m, &error->device_info, &error->runtime_info,
813 			       &error->driver_caps);
814 	err_print_params(m, &error->params);
815 	err_print_uc(m, &error->uc);
816 }
817 
818 static int err_print_to_sgl(struct i915_gpu_state *error)
819 {
820 	struct drm_i915_error_state_buf m;
821 
822 	if (IS_ERR(error))
823 		return PTR_ERR(error);
824 
825 	if (READ_ONCE(error->sgl))
826 		return 0;
827 
828 	memset(&m, 0, sizeof(m));
829 	m.i915 = error->i915;
830 
831 	__err_print_to_sgl(&m, error);
832 
833 	if (m.buf) {
834 		__sg_set_buf(m.cur++, m.buf, m.bytes, m.iter);
835 		m.bytes = 0;
836 		m.buf = NULL;
837 	}
838 	if (m.cur) {
839 		GEM_BUG_ON(m.end < m.cur);
840 		sg_mark_end(m.cur - 1);
841 	}
842 	GEM_BUG_ON(m.sgl && !m.cur);
843 
844 	if (m.err) {
845 		err_free_sgl(m.sgl);
846 		return m.err;
847 	}
848 
849 	if (cmpxchg(&error->sgl, NULL, m.sgl))
850 		err_free_sgl(m.sgl);
851 
852 	return 0;
853 }
854 
855 ssize_t i915_gpu_state_copy_to_buffer(struct i915_gpu_state *error,
856 				      char *buf, loff_t off, size_t rem)
857 {
858 	struct scatterlist *sg;
859 	size_t count;
860 	loff_t pos;
861 	int err;
862 
863 	if (!error || !rem)
864 		return 0;
865 
866 	err = err_print_to_sgl(error);
867 	if (err)
868 		return err;
869 
870 	sg = READ_ONCE(error->fit);
871 	if (!sg || off < sg->dma_address)
872 		sg = error->sgl;
873 	if (!sg)
874 		return 0;
875 
876 	pos = sg->dma_address;
877 	count = 0;
878 	do {
879 		size_t len, start;
880 
881 		if (sg_is_chain(sg)) {
882 			sg = sg_chain_ptr(sg);
883 			GEM_BUG_ON(sg_is_chain(sg));
884 		}
885 
886 		len = sg->length;
887 		if (pos + len <= off) {
888 			pos += len;
889 			continue;
890 		}
891 
892 		start = sg->offset;
893 		if (pos < off) {
894 			GEM_BUG_ON(off - pos > len);
895 			len -= off - pos;
896 			start += off - pos;
897 			pos = off;
898 		}
899 
900 		len = min(len, rem);
901 		GEM_BUG_ON(!len || len > sg->length);
902 
903 		memcpy(buf, page_address(sg_page(sg)) + start, len);
904 
905 		count += len;
906 		pos += len;
907 
908 		buf += len;
909 		rem -= len;
910 		if (!rem) {
911 			WRITE_ONCE(error->fit, sg);
912 			break;
913 		}
914 	} while (!sg_is_last(sg++));
915 
916 	return count;
917 }
918 
919 static void i915_error_object_free(struct drm_i915_error_object *obj)
920 {
921 	int page;
922 
923 	if (obj == NULL)
924 		return;
925 
926 	for (page = 0; page < obj->page_count; page++)
927 		free_page((unsigned long)obj->pages[page]);
928 
929 	kfree(obj);
930 }
931 
932 
933 static void cleanup_params(struct i915_gpu_state *error)
934 {
935 	i915_params_free(&error->params);
936 }
937 
938 static void cleanup_uc_state(struct i915_gpu_state *error)
939 {
940 	struct i915_error_uc *error_uc = &error->uc;
941 
942 	kfree(error_uc->guc_fw.path);
943 	kfree(error_uc->huc_fw.path);
944 	i915_error_object_free(error_uc->guc_log);
945 }
946 
947 void __i915_gpu_state_free(struct kref *error_ref)
948 {
949 	struct i915_gpu_state *error =
950 		container_of(error_ref, typeof(*error), ref);
951 	long i, j;
952 
953 	for (i = 0; i < ARRAY_SIZE(error->engine); i++) {
954 		struct drm_i915_error_engine *ee = &error->engine[i];
955 
956 		for (j = 0; j < ee->user_bo_count; j++)
957 			i915_error_object_free(ee->user_bo[j]);
958 		kfree(ee->user_bo);
959 
960 		i915_error_object_free(ee->batchbuffer);
961 		i915_error_object_free(ee->wa_batchbuffer);
962 		i915_error_object_free(ee->ringbuffer);
963 		i915_error_object_free(ee->hws_page);
964 		i915_error_object_free(ee->ctx);
965 		i915_error_object_free(ee->wa_ctx);
966 
967 		kfree(ee->requests);
968 	}
969 
970 	for (i = 0; i < ARRAY_SIZE(error->active_bo); i++)
971 		kfree(error->active_bo[i]);
972 	kfree(error->pinned_bo);
973 
974 	kfree(error->overlay);
975 	kfree(error->display);
976 
977 	cleanup_params(error);
978 	cleanup_uc_state(error);
979 
980 	err_free_sgl(error->sgl);
981 	kfree(error);
982 }
983 
984 static struct drm_i915_error_object *
985 i915_error_object_create(struct drm_i915_private *i915,
986 			 struct i915_vma *vma)
987 {
988 	struct i915_ggtt *ggtt = &i915->ggtt;
989 	const u64 slot = ggtt->error_capture.start;
990 	struct drm_i915_error_object *dst;
991 	struct compress compress;
992 	unsigned long num_pages;
993 	struct sgt_iter iter;
994 	dma_addr_t dma;
995 	int ret;
996 
997 	if (!vma || !vma->pages)
998 		return NULL;
999 
1000 	num_pages = min_t(u64, vma->size, vma->obj->base.size) >> PAGE_SHIFT;
1001 	num_pages = DIV_ROUND_UP(10 * num_pages, 8); /* worstcase zlib growth */
1002 	dst = kmalloc(sizeof(*dst) + num_pages * sizeof(u32 *),
1003 		      GFP_ATOMIC | __GFP_NOWARN);
1004 	if (!dst)
1005 		return NULL;
1006 
1007 	dst->gtt_offset = vma->node.start;
1008 	dst->gtt_size = vma->node.size;
1009 	dst->num_pages = num_pages;
1010 	dst->page_count = 0;
1011 	dst->unused = 0;
1012 
1013 	if (!compress_init(&compress)) {
1014 		kfree(dst);
1015 		return NULL;
1016 	}
1017 
1018 	ret = -EINVAL;
1019 	for_each_sgt_dma(dma, iter, vma->pages) {
1020 		void __iomem *s;
1021 
1022 		ggtt->vm.insert_page(&ggtt->vm, dma, slot, I915_CACHE_NONE, 0);
1023 
1024 		s = io_mapping_map_atomic_wc(&ggtt->iomap, slot);
1025 		ret = compress_page(&compress, (void  __force *)s, dst);
1026 		io_mapping_unmap_atomic(s);
1027 		if (ret)
1028 			break;
1029 	}
1030 
1031 	if (ret || compress_flush(&compress, dst)) {
1032 		while (dst->page_count--)
1033 			free_page((unsigned long)dst->pages[dst->page_count]);
1034 		kfree(dst);
1035 		dst = NULL;
1036 	}
1037 
1038 	compress_fini(&compress, dst);
1039 	return dst;
1040 }
1041 
1042 static void capture_bo(struct drm_i915_error_buffer *err,
1043 		       struct i915_vma *vma)
1044 {
1045 	struct drm_i915_gem_object *obj = vma->obj;
1046 
1047 	err->size = obj->base.size;
1048 	err->name = obj->base.name;
1049 
1050 	err->gtt_offset = vma->node.start;
1051 	err->read_domains = obj->read_domains;
1052 	err->write_domain = obj->write_domain;
1053 	err->fence_reg = vma->fence ? vma->fence->id : -1;
1054 	err->tiling = i915_gem_object_get_tiling(obj);
1055 	err->dirty = obj->mm.dirty;
1056 	err->purgeable = obj->mm.madv != I915_MADV_WILLNEED;
1057 	err->userptr = obj->userptr.mm != NULL;
1058 	err->cache_level = obj->cache_level;
1059 }
1060 
1061 static u32 capture_error_bo(struct drm_i915_error_buffer *err,
1062 			    int count, struct list_head *head,
1063 			    unsigned int flags)
1064 #define ACTIVE_ONLY BIT(0)
1065 #define PINNED_ONLY BIT(1)
1066 {
1067 	struct i915_vma *vma;
1068 	int i = 0;
1069 
1070 	list_for_each_entry(vma, head, vm_link) {
1071 		if (!vma->obj)
1072 			continue;
1073 
1074 		if (flags & ACTIVE_ONLY && !i915_vma_is_active(vma))
1075 			continue;
1076 
1077 		if (flags & PINNED_ONLY && !i915_vma_is_pinned(vma))
1078 			continue;
1079 
1080 		capture_bo(err++, vma);
1081 		if (++i == count)
1082 			break;
1083 	}
1084 
1085 	return i;
1086 }
1087 
1088 /*
1089  * Generate a semi-unique error code. The code is not meant to have meaning, The
1090  * code's only purpose is to try to prevent false duplicated bug reports by
1091  * grossly estimating a GPU error state.
1092  *
1093  * TODO Ideally, hashing the batchbuffer would be a very nice way to determine
1094  * the hang if we could strip the GTT offset information from it.
1095  *
1096  * It's only a small step better than a random number in its current form.
1097  */
1098 static u32 i915_error_generate_code(struct i915_gpu_state *error,
1099 				    intel_engine_mask_t engine_mask)
1100 {
1101 	/*
1102 	 * IPEHR would be an ideal way to detect errors, as it's the gross
1103 	 * measure of "the command that hung." However, has some very common
1104 	 * synchronization commands which almost always appear in the case
1105 	 * strictly a client bug. Use instdone to differentiate those some.
1106 	 */
1107 	if (engine_mask) {
1108 		struct drm_i915_error_engine *ee =
1109 			&error->engine[ffs(engine_mask)];
1110 
1111 		return ee->ipehr ^ ee->instdone.instdone;
1112 	}
1113 
1114 	return 0;
1115 }
1116 
1117 static void gem_record_fences(struct i915_gpu_state *error)
1118 {
1119 	struct drm_i915_private *dev_priv = error->i915;
1120 	int i;
1121 
1122 	if (INTEL_GEN(dev_priv) >= 6) {
1123 		for (i = 0; i < dev_priv->num_fence_regs; i++)
1124 			error->fence[i] = I915_READ64(FENCE_REG_GEN6_LO(i));
1125 	} else if (INTEL_GEN(dev_priv) >= 4) {
1126 		for (i = 0; i < dev_priv->num_fence_regs; i++)
1127 			error->fence[i] = I915_READ64(FENCE_REG_965_LO(i));
1128 	} else {
1129 		for (i = 0; i < dev_priv->num_fence_regs; i++)
1130 			error->fence[i] = I915_READ(FENCE_REG(i));
1131 	}
1132 	error->nfence = i;
1133 }
1134 
1135 static void error_record_engine_registers(struct i915_gpu_state *error,
1136 					  struct intel_engine_cs *engine,
1137 					  struct drm_i915_error_engine *ee)
1138 {
1139 	struct drm_i915_private *dev_priv = engine->i915;
1140 
1141 	if (INTEL_GEN(dev_priv) >= 6) {
1142 		ee->rc_psmi = ENGINE_READ(engine, RING_PSMI_CTL);
1143 		if (INTEL_GEN(dev_priv) >= 8)
1144 			ee->fault_reg = I915_READ(GEN8_RING_FAULT_REG);
1145 		else
1146 			ee->fault_reg = I915_READ(RING_FAULT_REG(engine));
1147 	}
1148 
1149 	if (INTEL_GEN(dev_priv) >= 4) {
1150 		ee->faddr = ENGINE_READ(engine, RING_DMA_FADD);
1151 		ee->ipeir = ENGINE_READ(engine, RING_IPEIR);
1152 		ee->ipehr = ENGINE_READ(engine, RING_IPEHR);
1153 		ee->instps = ENGINE_READ(engine, RING_INSTPS);
1154 		ee->bbaddr = ENGINE_READ(engine, RING_BBADDR);
1155 		if (INTEL_GEN(dev_priv) >= 8) {
1156 			ee->faddr |= (u64)ENGINE_READ(engine, RING_DMA_FADD_UDW) << 32;
1157 			ee->bbaddr |= (u64)ENGINE_READ(engine, RING_BBADDR_UDW) << 32;
1158 		}
1159 		ee->bbstate = ENGINE_READ(engine, RING_BBSTATE);
1160 	} else {
1161 		ee->faddr = ENGINE_READ(engine, DMA_FADD_I8XX);
1162 		ee->ipeir = ENGINE_READ(engine, IPEIR);
1163 		ee->ipehr = ENGINE_READ(engine, IPEHR);
1164 	}
1165 
1166 	intel_engine_get_instdone(engine, &ee->instdone);
1167 
1168 	ee->instpm = ENGINE_READ(engine, RING_INSTPM);
1169 	ee->acthd = intel_engine_get_active_head(engine);
1170 	ee->start = ENGINE_READ(engine, RING_START);
1171 	ee->head = ENGINE_READ(engine, RING_HEAD);
1172 	ee->tail = ENGINE_READ(engine, RING_TAIL);
1173 	ee->ctl = ENGINE_READ(engine, RING_CTL);
1174 	if (INTEL_GEN(dev_priv) > 2)
1175 		ee->mode = ENGINE_READ(engine, RING_MI_MODE);
1176 
1177 	if (!HWS_NEEDS_PHYSICAL(dev_priv)) {
1178 		i915_reg_t mmio;
1179 
1180 		if (IS_GEN(dev_priv, 7)) {
1181 			switch (engine->id) {
1182 			default:
1183 				MISSING_CASE(engine->id);
1184 			case RCS0:
1185 				mmio = RENDER_HWS_PGA_GEN7;
1186 				break;
1187 			case BCS0:
1188 				mmio = BLT_HWS_PGA_GEN7;
1189 				break;
1190 			case VCS0:
1191 				mmio = BSD_HWS_PGA_GEN7;
1192 				break;
1193 			case VECS0:
1194 				mmio = VEBOX_HWS_PGA_GEN7;
1195 				break;
1196 			}
1197 		} else if (IS_GEN(engine->i915, 6)) {
1198 			mmio = RING_HWS_PGA_GEN6(engine->mmio_base);
1199 		} else {
1200 			/* XXX: gen8 returns to sanity */
1201 			mmio = RING_HWS_PGA(engine->mmio_base);
1202 		}
1203 
1204 		ee->hws = I915_READ(mmio);
1205 	}
1206 
1207 	ee->idle = intel_engine_is_idle(engine);
1208 	if (!ee->idle)
1209 		ee->hangcheck_timestamp = engine->hangcheck.action_timestamp;
1210 	ee->reset_count = i915_reset_engine_count(&dev_priv->gpu_error,
1211 						  engine);
1212 
1213 	if (HAS_PPGTT(dev_priv)) {
1214 		int i;
1215 
1216 		ee->vm_info.gfx_mode = I915_READ(RING_MODE_GEN7(engine));
1217 
1218 		if (IS_GEN(dev_priv, 6)) {
1219 			ee->vm_info.pp_dir_base =
1220 				ENGINE_READ(engine, RING_PP_DIR_BASE_READ);
1221 		} else if (IS_GEN(dev_priv, 7)) {
1222 			ee->vm_info.pp_dir_base =
1223 				ENGINE_READ(engine, RING_PP_DIR_BASE);
1224 		} else if (INTEL_GEN(dev_priv) >= 8) {
1225 			u32 base = engine->mmio_base;
1226 
1227 			for (i = 0; i < 4; i++) {
1228 				ee->vm_info.pdp[i] =
1229 					I915_READ(GEN8_RING_PDP_UDW(base, i));
1230 				ee->vm_info.pdp[i] <<= 32;
1231 				ee->vm_info.pdp[i] |=
1232 					I915_READ(GEN8_RING_PDP_LDW(base, i));
1233 			}
1234 		}
1235 	}
1236 }
1237 
1238 static void record_request(struct i915_request *request,
1239 			   struct drm_i915_error_request *erq)
1240 {
1241 	struct i915_gem_context *ctx = request->gem_context;
1242 
1243 	erq->flags = request->fence.flags;
1244 	erq->context = request->fence.context;
1245 	erq->seqno = request->fence.seqno;
1246 	erq->sched_attr = request->sched.attr;
1247 	erq->jiffies = request->emitted_jiffies;
1248 	erq->start = i915_ggtt_offset(request->ring->vma);
1249 	erq->head = request->head;
1250 	erq->tail = request->tail;
1251 
1252 	rcu_read_lock();
1253 	erq->pid = ctx->pid ? pid_nr(ctx->pid) : 0;
1254 	rcu_read_unlock();
1255 }
1256 
1257 static void engine_record_requests(struct intel_engine_cs *engine,
1258 				   struct i915_request *first,
1259 				   struct drm_i915_error_engine *ee)
1260 {
1261 	struct i915_request *request;
1262 	int count;
1263 
1264 	count = 0;
1265 	request = first;
1266 	list_for_each_entry_from(request, &engine->timeline.requests, link)
1267 		count++;
1268 	if (!count)
1269 		return;
1270 
1271 	ee->requests = kcalloc(count, sizeof(*ee->requests), GFP_ATOMIC);
1272 	if (!ee->requests)
1273 		return;
1274 
1275 	ee->num_requests = count;
1276 
1277 	count = 0;
1278 	request = first;
1279 	list_for_each_entry_from(request, &engine->timeline.requests, link) {
1280 		if (count >= ee->num_requests) {
1281 			/*
1282 			 * If the ring request list was changed in
1283 			 * between the point where the error request
1284 			 * list was created and dimensioned and this
1285 			 * point then just exit early to avoid crashes.
1286 			 *
1287 			 * We don't need to communicate that the
1288 			 * request list changed state during error
1289 			 * state capture and that the error state is
1290 			 * slightly incorrect as a consequence since we
1291 			 * are typically only interested in the request
1292 			 * list state at the point of error state
1293 			 * capture, not in any changes happening during
1294 			 * the capture.
1295 			 */
1296 			break;
1297 		}
1298 
1299 		record_request(request, &ee->requests[count++]);
1300 	}
1301 	ee->num_requests = count;
1302 }
1303 
1304 static void error_record_engine_execlists(struct intel_engine_cs *engine,
1305 					  struct drm_i915_error_engine *ee)
1306 {
1307 	const struct intel_engine_execlists * const execlists = &engine->execlists;
1308 	unsigned int n;
1309 
1310 	for (n = 0; n < execlists_num_ports(execlists); n++) {
1311 		struct i915_request *rq = port_request(&execlists->port[n]);
1312 
1313 		if (!rq)
1314 			break;
1315 
1316 		record_request(rq, &ee->execlist[n]);
1317 	}
1318 
1319 	ee->num_ports = n;
1320 }
1321 
1322 static void record_context(struct drm_i915_error_context *e,
1323 			   struct i915_gem_context *ctx)
1324 {
1325 	if (ctx->pid) {
1326 		struct task_struct *task;
1327 
1328 		rcu_read_lock();
1329 		task = pid_task(ctx->pid, PIDTYPE_PID);
1330 		if (task) {
1331 			strcpy(e->comm, task->comm);
1332 			e->pid = task->pid;
1333 		}
1334 		rcu_read_unlock();
1335 	}
1336 
1337 	e->hw_id = ctx->hw_id;
1338 	e->sched_attr = ctx->sched;
1339 	e->guilty = atomic_read(&ctx->guilty_count);
1340 	e->active = atomic_read(&ctx->active_count);
1341 }
1342 
1343 static void request_record_user_bo(struct i915_request *request,
1344 				   struct drm_i915_error_engine *ee)
1345 {
1346 	struct i915_capture_list *c;
1347 	struct drm_i915_error_object **bo;
1348 	long count, max;
1349 
1350 	max = 0;
1351 	for (c = request->capture_list; c; c = c->next)
1352 		max++;
1353 	if (!max)
1354 		return;
1355 
1356 	bo = kmalloc_array(max, sizeof(*bo), GFP_ATOMIC);
1357 	if (!bo) {
1358 		/* If we can't capture everything, try to capture something. */
1359 		max = min_t(long, max, PAGE_SIZE / sizeof(*bo));
1360 		bo = kmalloc_array(max, sizeof(*bo), GFP_ATOMIC);
1361 	}
1362 	if (!bo)
1363 		return;
1364 
1365 	count = 0;
1366 	for (c = request->capture_list; c; c = c->next) {
1367 		bo[count] = i915_error_object_create(request->i915, c->vma);
1368 		if (!bo[count])
1369 			break;
1370 		if (++count == max)
1371 			break;
1372 	}
1373 
1374 	ee->user_bo = bo;
1375 	ee->user_bo_count = count;
1376 }
1377 
1378 static struct drm_i915_error_object *
1379 capture_object(struct drm_i915_private *dev_priv,
1380 	       struct drm_i915_gem_object *obj)
1381 {
1382 	if (obj && i915_gem_object_has_pages(obj)) {
1383 		struct i915_vma fake = {
1384 			.node = { .start = U64_MAX, .size = obj->base.size },
1385 			.size = obj->base.size,
1386 			.pages = obj->mm.pages,
1387 			.obj = obj,
1388 		};
1389 
1390 		return i915_error_object_create(dev_priv, &fake);
1391 	} else {
1392 		return NULL;
1393 	}
1394 }
1395 
1396 static void gem_record_rings(struct i915_gpu_state *error)
1397 {
1398 	struct drm_i915_private *i915 = error->i915;
1399 	struct i915_ggtt *ggtt = &i915->ggtt;
1400 	int i;
1401 
1402 	for (i = 0; i < I915_NUM_ENGINES; i++) {
1403 		struct intel_engine_cs *engine = i915->engine[i];
1404 		struct drm_i915_error_engine *ee = &error->engine[i];
1405 		struct i915_request *request;
1406 
1407 		ee->engine_id = -1;
1408 
1409 		if (!engine)
1410 			continue;
1411 
1412 		ee->engine_id = i;
1413 
1414 		error_record_engine_registers(error, engine, ee);
1415 		error_record_engine_execlists(engine, ee);
1416 
1417 		request = intel_engine_find_active_request(engine);
1418 		if (request) {
1419 			struct i915_gem_context *ctx = request->gem_context;
1420 			struct intel_ring *ring;
1421 
1422 			ee->vm = ctx->ppgtt ? &ctx->ppgtt->vm : &ggtt->vm;
1423 
1424 			record_context(&ee->context, ctx);
1425 
1426 			/* We need to copy these to an anonymous buffer
1427 			 * as the simplest method to avoid being overwritten
1428 			 * by userspace.
1429 			 */
1430 			ee->batchbuffer =
1431 				i915_error_object_create(i915, request->batch);
1432 
1433 			if (HAS_BROKEN_CS_TLB(i915))
1434 				ee->wa_batchbuffer =
1435 					i915_error_object_create(i915,
1436 								 i915->gt.scratch);
1437 			request_record_user_bo(request, ee);
1438 
1439 			ee->ctx =
1440 				i915_error_object_create(i915,
1441 							 request->hw_context->state);
1442 
1443 			error->simulated |=
1444 				i915_gem_context_no_error_capture(ctx);
1445 
1446 			ee->rq_head = request->head;
1447 			ee->rq_post = request->postfix;
1448 			ee->rq_tail = request->tail;
1449 
1450 			ring = request->ring;
1451 			ee->cpu_ring_head = ring->head;
1452 			ee->cpu_ring_tail = ring->tail;
1453 			ee->ringbuffer =
1454 				i915_error_object_create(i915, ring->vma);
1455 
1456 			engine_record_requests(engine, request, ee);
1457 		}
1458 
1459 		ee->hws_page =
1460 			i915_error_object_create(i915,
1461 						 engine->status_page.vma);
1462 
1463 		ee->wa_ctx = i915_error_object_create(i915, engine->wa_ctx.vma);
1464 
1465 		ee->default_state = capture_object(i915, engine->default_state);
1466 	}
1467 }
1468 
1469 static void gem_capture_vm(struct i915_gpu_state *error,
1470 			   struct i915_address_space *vm,
1471 			   int idx)
1472 {
1473 	struct drm_i915_error_buffer *active_bo;
1474 	struct i915_vma *vma;
1475 	int count;
1476 
1477 	count = 0;
1478 	list_for_each_entry(vma, &vm->bound_list, vm_link)
1479 		if (i915_vma_is_active(vma))
1480 			count++;
1481 
1482 	active_bo = NULL;
1483 	if (count)
1484 		active_bo = kcalloc(count, sizeof(*active_bo), GFP_ATOMIC);
1485 	if (active_bo)
1486 		count = capture_error_bo(active_bo,
1487 					 count, &vm->bound_list,
1488 					 ACTIVE_ONLY);
1489 	else
1490 		count = 0;
1491 
1492 	error->active_vm[idx] = vm;
1493 	error->active_bo[idx] = active_bo;
1494 	error->active_bo_count[idx] = count;
1495 }
1496 
1497 static void capture_active_buffers(struct i915_gpu_state *error)
1498 {
1499 	int cnt = 0, i, j;
1500 
1501 	BUILD_BUG_ON(ARRAY_SIZE(error->engine) > ARRAY_SIZE(error->active_bo));
1502 	BUILD_BUG_ON(ARRAY_SIZE(error->active_bo) != ARRAY_SIZE(error->active_vm));
1503 	BUILD_BUG_ON(ARRAY_SIZE(error->active_bo) != ARRAY_SIZE(error->active_bo_count));
1504 
1505 	/* Scan each engine looking for unique active contexts/vm */
1506 	for (i = 0; i < ARRAY_SIZE(error->engine); i++) {
1507 		struct drm_i915_error_engine *ee = &error->engine[i];
1508 		bool found;
1509 
1510 		if (!ee->vm)
1511 			continue;
1512 
1513 		found = false;
1514 		for (j = 0; j < i && !found; j++)
1515 			found = error->engine[j].vm == ee->vm;
1516 		if (!found)
1517 			gem_capture_vm(error, ee->vm, cnt++);
1518 	}
1519 }
1520 
1521 static void capture_pinned_buffers(struct i915_gpu_state *error)
1522 {
1523 	struct i915_address_space *vm = &error->i915->ggtt.vm;
1524 	struct drm_i915_error_buffer *bo;
1525 	struct i915_vma *vma;
1526 	int count;
1527 
1528 	count = 0;
1529 	list_for_each_entry(vma, &vm->bound_list, vm_link)
1530 		count++;
1531 
1532 	bo = NULL;
1533 	if (count)
1534 		bo = kcalloc(count, sizeof(*bo), GFP_ATOMIC);
1535 	if (!bo)
1536 		return;
1537 
1538 	error->pinned_bo_count =
1539 		capture_error_bo(bo, count, &vm->bound_list, PINNED_ONLY);
1540 	error->pinned_bo = bo;
1541 }
1542 
1543 static void capture_uc_state(struct i915_gpu_state *error)
1544 {
1545 	struct drm_i915_private *i915 = error->i915;
1546 	struct i915_error_uc *error_uc = &error->uc;
1547 
1548 	/* Capturing uC state won't be useful if there is no GuC */
1549 	if (!error->device_info.has_guc)
1550 		return;
1551 
1552 	error_uc->guc_fw = i915->guc.fw;
1553 	error_uc->huc_fw = i915->huc.fw;
1554 
1555 	/* Non-default firmware paths will be specified by the modparam.
1556 	 * As modparams are generally accesible from the userspace make
1557 	 * explicit copies of the firmware paths.
1558 	 */
1559 	error_uc->guc_fw.path = kstrdup(i915->guc.fw.path, GFP_ATOMIC);
1560 	error_uc->huc_fw.path = kstrdup(i915->huc.fw.path, GFP_ATOMIC);
1561 	error_uc->guc_log = i915_error_object_create(i915, i915->guc.log.vma);
1562 }
1563 
1564 /* Capture all registers which don't fit into another category. */
1565 static void capture_reg_state(struct i915_gpu_state *error)
1566 {
1567 	struct drm_i915_private *dev_priv = error->i915;
1568 	int i;
1569 
1570 	/* General organization
1571 	 * 1. Registers specific to a single generation
1572 	 * 2. Registers which belong to multiple generations
1573 	 * 3. Feature specific registers.
1574 	 * 4. Everything else
1575 	 * Please try to follow the order.
1576 	 */
1577 
1578 	/* 1: Registers specific to a single generation */
1579 	if (IS_VALLEYVIEW(dev_priv)) {
1580 		error->gtier[0] = I915_READ(GTIER);
1581 		error->ier = I915_READ(VLV_IER);
1582 		error->forcewake = I915_READ_FW(FORCEWAKE_VLV);
1583 	}
1584 
1585 	if (IS_GEN(dev_priv, 7))
1586 		error->err_int = I915_READ(GEN7_ERR_INT);
1587 
1588 	if (INTEL_GEN(dev_priv) >= 8) {
1589 		error->fault_data0 = I915_READ(GEN8_FAULT_TLB_DATA0);
1590 		error->fault_data1 = I915_READ(GEN8_FAULT_TLB_DATA1);
1591 	}
1592 
1593 	if (IS_GEN(dev_priv, 6)) {
1594 		error->forcewake = I915_READ_FW(FORCEWAKE);
1595 		error->gab_ctl = I915_READ(GAB_CTL);
1596 		error->gfx_mode = I915_READ(GFX_MODE);
1597 	}
1598 
1599 	/* 2: Registers which belong to multiple generations */
1600 	if (INTEL_GEN(dev_priv) >= 7)
1601 		error->forcewake = I915_READ_FW(FORCEWAKE_MT);
1602 
1603 	if (INTEL_GEN(dev_priv) >= 6) {
1604 		error->derrmr = I915_READ(DERRMR);
1605 		error->error = I915_READ(ERROR_GEN6);
1606 		error->done_reg = I915_READ(DONE_REG);
1607 	}
1608 
1609 	if (INTEL_GEN(dev_priv) >= 5)
1610 		error->ccid = I915_READ(CCID(RENDER_RING_BASE));
1611 
1612 	/* 3: Feature specific registers */
1613 	if (IS_GEN_RANGE(dev_priv, 6, 7)) {
1614 		error->gam_ecochk = I915_READ(GAM_ECOCHK);
1615 		error->gac_eco = I915_READ(GAC_ECO_BITS);
1616 	}
1617 
1618 	/* 4: Everything else */
1619 	if (INTEL_GEN(dev_priv) >= 11) {
1620 		error->ier = I915_READ(GEN8_DE_MISC_IER);
1621 		error->gtier[0] = I915_READ(GEN11_RENDER_COPY_INTR_ENABLE);
1622 		error->gtier[1] = I915_READ(GEN11_VCS_VECS_INTR_ENABLE);
1623 		error->gtier[2] = I915_READ(GEN11_GUC_SG_INTR_ENABLE);
1624 		error->gtier[3] = I915_READ(GEN11_GPM_WGBOXPERF_INTR_ENABLE);
1625 		error->gtier[4] = I915_READ(GEN11_CRYPTO_RSVD_INTR_ENABLE);
1626 		error->gtier[5] = I915_READ(GEN11_GUNIT_CSME_INTR_ENABLE);
1627 		error->ngtier = 6;
1628 	} else if (INTEL_GEN(dev_priv) >= 8) {
1629 		error->ier = I915_READ(GEN8_DE_MISC_IER);
1630 		for (i = 0; i < 4; i++)
1631 			error->gtier[i] = I915_READ(GEN8_GT_IER(i));
1632 		error->ngtier = 4;
1633 	} else if (HAS_PCH_SPLIT(dev_priv)) {
1634 		error->ier = I915_READ(DEIER);
1635 		error->gtier[0] = I915_READ(GTIER);
1636 		error->ngtier = 1;
1637 	} else if (IS_GEN(dev_priv, 2)) {
1638 		error->ier = I915_READ16(GEN2_IER);
1639 	} else if (!IS_VALLEYVIEW(dev_priv)) {
1640 		error->ier = I915_READ(GEN2_IER);
1641 	}
1642 	error->eir = I915_READ(EIR);
1643 	error->pgtbl_er = I915_READ(PGTBL_ER);
1644 }
1645 
1646 static const char *
1647 error_msg(struct i915_gpu_state *error,
1648 	  intel_engine_mask_t engines, const char *msg)
1649 {
1650 	int len;
1651 	int i;
1652 
1653 	for (i = 0; i < ARRAY_SIZE(error->engine); i++)
1654 		if (!error->engine[i].context.pid)
1655 			engines &= ~BIT(i);
1656 
1657 	len = scnprintf(error->error_msg, sizeof(error->error_msg),
1658 			"GPU HANG: ecode %d:%x:0x%08x",
1659 			INTEL_GEN(error->i915), engines,
1660 			i915_error_generate_code(error, engines));
1661 	if (engines) {
1662 		/* Just show the first executing process, more is confusing */
1663 		i = __ffs(engines);
1664 		len += scnprintf(error->error_msg + len,
1665 				 sizeof(error->error_msg) - len,
1666 				 ", in %s [%d]",
1667 				 error->engine[i].context.comm,
1668 				 error->engine[i].context.pid);
1669 	}
1670 	if (msg)
1671 		len += scnprintf(error->error_msg + len,
1672 				 sizeof(error->error_msg) - len,
1673 				 ", %s", msg);
1674 
1675 	return error->error_msg;
1676 }
1677 
1678 static void capture_gen_state(struct i915_gpu_state *error)
1679 {
1680 	struct drm_i915_private *i915 = error->i915;
1681 
1682 	error->awake = i915->gt.awake;
1683 	error->wakelock = atomic_read(&i915->runtime_pm.wakeref_count);
1684 	error->suspended = i915->runtime_pm.suspended;
1685 
1686 	error->iommu = -1;
1687 #ifdef CONFIG_INTEL_IOMMU
1688 	error->iommu = intel_iommu_gfx_mapped;
1689 #endif
1690 	error->reset_count = i915_reset_count(&i915->gpu_error);
1691 	error->suspend_count = i915->suspend_count;
1692 
1693 	memcpy(&error->device_info,
1694 	       INTEL_INFO(i915),
1695 	       sizeof(error->device_info));
1696 	memcpy(&error->runtime_info,
1697 	       RUNTIME_INFO(i915),
1698 	       sizeof(error->runtime_info));
1699 	error->driver_caps = i915->caps;
1700 }
1701 
1702 static void capture_params(struct i915_gpu_state *error)
1703 {
1704 	i915_params_copy(&error->params, &i915_modparams);
1705 }
1706 
1707 static unsigned long capture_find_epoch(const struct i915_gpu_state *error)
1708 {
1709 	unsigned long epoch = error->capture;
1710 	int i;
1711 
1712 	for (i = 0; i < ARRAY_SIZE(error->engine); i++) {
1713 		const struct drm_i915_error_engine *ee = &error->engine[i];
1714 
1715 		if (ee->hangcheck_timestamp &&
1716 		    time_before(ee->hangcheck_timestamp, epoch))
1717 			epoch = ee->hangcheck_timestamp;
1718 	}
1719 
1720 	return epoch;
1721 }
1722 
1723 static void capture_finish(struct i915_gpu_state *error)
1724 {
1725 	struct i915_ggtt *ggtt = &error->i915->ggtt;
1726 	const u64 slot = ggtt->error_capture.start;
1727 
1728 	ggtt->vm.clear_range(&ggtt->vm, slot, PAGE_SIZE);
1729 }
1730 
1731 static int capture(void *data)
1732 {
1733 	struct i915_gpu_state *error = data;
1734 
1735 	error->time = ktime_get_real();
1736 	error->boottime = ktime_get_boottime();
1737 	error->uptime = ktime_sub(ktime_get(),
1738 				  error->i915->gt.last_init_time);
1739 	error->capture = jiffies;
1740 
1741 	capture_params(error);
1742 	capture_gen_state(error);
1743 	capture_uc_state(error);
1744 	capture_reg_state(error);
1745 	gem_record_fences(error);
1746 	gem_record_rings(error);
1747 	capture_active_buffers(error);
1748 	capture_pinned_buffers(error);
1749 
1750 	error->overlay = intel_overlay_capture_error_state(error->i915);
1751 	error->display = intel_display_capture_error_state(error->i915);
1752 
1753 	error->epoch = capture_find_epoch(error);
1754 
1755 	capture_finish(error);
1756 	return 0;
1757 }
1758 
1759 #define DAY_AS_SECONDS(x) (24 * 60 * 60 * (x))
1760 
1761 struct i915_gpu_state *
1762 i915_capture_gpu_state(struct drm_i915_private *i915)
1763 {
1764 	struct i915_gpu_state *error;
1765 
1766 	/* Check if GPU capture has been disabled */
1767 	error = READ_ONCE(i915->gpu_error.first_error);
1768 	if (IS_ERR(error))
1769 		return error;
1770 
1771 	error = kzalloc(sizeof(*error), GFP_ATOMIC);
1772 	if (!error) {
1773 		i915_disable_error_state(i915, -ENOMEM);
1774 		return ERR_PTR(-ENOMEM);
1775 	}
1776 
1777 	kref_init(&error->ref);
1778 	error->i915 = i915;
1779 
1780 	stop_machine(capture, error, NULL);
1781 
1782 	return error;
1783 }
1784 
1785 /**
1786  * i915_capture_error_state - capture an error record for later analysis
1787  * @i915: i915 device
1788  * @engine_mask: the mask of engines triggering the hang
1789  * @msg: a message to insert into the error capture header
1790  *
1791  * Should be called when an error is detected (either a hang or an error
1792  * interrupt) to capture error state from the time of the error.  Fills
1793  * out a structure which becomes available in debugfs for user level tools
1794  * to pick up.
1795  */
1796 void i915_capture_error_state(struct drm_i915_private *i915,
1797 			      intel_engine_mask_t engine_mask,
1798 			      const char *msg)
1799 {
1800 	static bool warned;
1801 	struct i915_gpu_state *error;
1802 	unsigned long flags;
1803 
1804 	if (!i915_modparams.error_capture)
1805 		return;
1806 
1807 	if (READ_ONCE(i915->gpu_error.first_error))
1808 		return;
1809 
1810 	error = i915_capture_gpu_state(i915);
1811 	if (IS_ERR(error))
1812 		return;
1813 
1814 	dev_info(i915->drm.dev, "%s\n", error_msg(error, engine_mask, msg));
1815 
1816 	if (!error->simulated) {
1817 		spin_lock_irqsave(&i915->gpu_error.lock, flags);
1818 		if (!i915->gpu_error.first_error) {
1819 			i915->gpu_error.first_error = error;
1820 			error = NULL;
1821 		}
1822 		spin_unlock_irqrestore(&i915->gpu_error.lock, flags);
1823 	}
1824 
1825 	if (error) {
1826 		__i915_gpu_state_free(&error->ref);
1827 		return;
1828 	}
1829 
1830 	if (!warned &&
1831 	    ktime_get_real_seconds() - DRIVER_TIMESTAMP < DAY_AS_SECONDS(180)) {
1832 		DRM_INFO("GPU hangs can indicate a bug anywhere in the entire gfx stack, including userspace.\n");
1833 		DRM_INFO("Please file a _new_ bug report on bugs.freedesktop.org against DRI -> DRM/Intel\n");
1834 		DRM_INFO("drm/i915 developers can then reassign to the right component if it's not a kernel issue.\n");
1835 		DRM_INFO("The gpu crash dump is required to analyze gpu hangs, so please always attach it.\n");
1836 		DRM_INFO("GPU crash dump saved to /sys/class/drm/card%d/error\n",
1837 			 i915->drm.primary->index);
1838 		warned = true;
1839 	}
1840 }
1841 
1842 struct i915_gpu_state *
1843 i915_first_error_state(struct drm_i915_private *i915)
1844 {
1845 	struct i915_gpu_state *error;
1846 
1847 	spin_lock_irq(&i915->gpu_error.lock);
1848 	error = i915->gpu_error.first_error;
1849 	if (!IS_ERR_OR_NULL(error))
1850 		i915_gpu_state_get(error);
1851 	spin_unlock_irq(&i915->gpu_error.lock);
1852 
1853 	return error;
1854 }
1855 
1856 void i915_reset_error_state(struct drm_i915_private *i915)
1857 {
1858 	struct i915_gpu_state *error;
1859 
1860 	spin_lock_irq(&i915->gpu_error.lock);
1861 	error = i915->gpu_error.first_error;
1862 	if (error != ERR_PTR(-ENODEV)) /* if disabled, always disabled */
1863 		i915->gpu_error.first_error = NULL;
1864 	spin_unlock_irq(&i915->gpu_error.lock);
1865 
1866 	if (!IS_ERR_OR_NULL(error))
1867 		i915_gpu_state_put(error);
1868 }
1869 
1870 void i915_disable_error_state(struct drm_i915_private *i915, int err)
1871 {
1872 	spin_lock_irq(&i915->gpu_error.lock);
1873 	if (!i915->gpu_error.first_error)
1874 		i915->gpu_error.first_error = ERR_PTR(err);
1875 	spin_unlock_irq(&i915->gpu_error.lock);
1876 }
1877