xref: /linux/drivers/gpu/drm/i915/i915_gpu_error.c (revision 76d9b92e68f2bb55890f935c5143f4fef97a935d)
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/debugfs.h>
32 #include <linux/highmem.h>
33 #include <linux/nmi.h>
34 #include <linux/pagevec.h>
35 #include <linux/scatterlist.h>
36 #include <linux/string_helpers.h>
37 #include <linux/utsname.h>
38 #include <linux/zlib.h>
39 
40 #include <drm/drm_cache.h>
41 #include <drm/drm_print.h>
42 
43 #include "display/intel_dmc.h"
44 #include "display/intel_overlay.h"
45 
46 #include "gem/i915_gem_context.h"
47 #include "gem/i915_gem_lmem.h"
48 #include "gt/intel_engine_regs.h"
49 #include "gt/intel_gt.h"
50 #include "gt/intel_gt_mcr.h"
51 #include "gt/intel_gt_pm.h"
52 #include "gt/intel_gt_regs.h"
53 #include "gt/uc/intel_guc_capture.h"
54 
55 #include "i915_driver.h"
56 #include "i915_drv.h"
57 #include "i915_gpu_error.h"
58 #include "i915_memcpy.h"
59 #include "i915_reg.h"
60 #include "i915_scatterlist.h"
61 #include "i915_sysfs.h"
62 #include "i915_utils.h"
63 
64 #define ALLOW_FAIL (__GFP_KSWAPD_RECLAIM | __GFP_RETRY_MAYFAIL | __GFP_NOWARN)
65 #define ATOMIC_MAYFAIL (GFP_ATOMIC | __GFP_NOWARN)
66 
67 static void __sg_set_buf(struct scatterlist *sg,
68 			 void *addr, unsigned int len, loff_t it)
69 {
70 	sg->page_link = (unsigned long)virt_to_page(addr);
71 	sg->offset = offset_in_page(addr);
72 	sg->length = len;
73 	sg->dma_address = it;
74 }
75 
76 static bool __i915_error_grow(struct drm_i915_error_state_buf *e, size_t len)
77 {
78 	if (!len)
79 		return false;
80 
81 	if (e->bytes + len + 1 <= e->size)
82 		return true;
83 
84 	if (e->bytes) {
85 		__sg_set_buf(e->cur++, e->buf, e->bytes, e->iter);
86 		e->iter += e->bytes;
87 		e->buf = NULL;
88 		e->bytes = 0;
89 	}
90 
91 	if (e->cur == e->end) {
92 		struct scatterlist *sgl;
93 
94 		sgl = (typeof(sgl))__get_free_page(ALLOW_FAIL);
95 		if (!sgl) {
96 			e->err = -ENOMEM;
97 			return false;
98 		}
99 
100 		if (e->cur) {
101 			e->cur->offset = 0;
102 			e->cur->length = 0;
103 			e->cur->page_link =
104 				(unsigned long)sgl | SG_CHAIN;
105 		} else {
106 			e->sgl = sgl;
107 		}
108 
109 		e->cur = sgl;
110 		e->end = sgl + SG_MAX_SINGLE_ALLOC - 1;
111 	}
112 
113 	e->size = ALIGN(len + 1, SZ_64K);
114 	e->buf = kmalloc(e->size, ALLOW_FAIL);
115 	if (!e->buf) {
116 		e->size = PAGE_ALIGN(len + 1);
117 		e->buf = kmalloc(e->size, GFP_KERNEL);
118 	}
119 	if (!e->buf) {
120 		e->err = -ENOMEM;
121 		return false;
122 	}
123 
124 	return true;
125 }
126 
127 __printf(2, 0)
128 static void i915_error_vprintf(struct drm_i915_error_state_buf *e,
129 			       const char *fmt, va_list args)
130 {
131 	va_list ap;
132 	int len;
133 
134 	if (e->err)
135 		return;
136 
137 	va_copy(ap, args);
138 	len = vsnprintf(NULL, 0, fmt, ap);
139 	va_end(ap);
140 	if (len <= 0) {
141 		e->err = len;
142 		return;
143 	}
144 
145 	if (!__i915_error_grow(e, len))
146 		return;
147 
148 	GEM_BUG_ON(e->bytes >= e->size);
149 	len = vscnprintf(e->buf + e->bytes, e->size - e->bytes, fmt, args);
150 	if (len < 0) {
151 		e->err = len;
152 		return;
153 	}
154 	e->bytes += len;
155 }
156 
157 static void i915_error_puts(struct drm_i915_error_state_buf *e, const char *str)
158 {
159 	unsigned len;
160 
161 	if (e->err || !str)
162 		return;
163 
164 	len = strlen(str);
165 	if (!__i915_error_grow(e, len))
166 		return;
167 
168 	GEM_BUG_ON(e->bytes + len > e->size);
169 	memcpy(e->buf + e->bytes, str, len);
170 	e->bytes += len;
171 }
172 
173 #define err_printf(e, ...) i915_error_printf(e, __VA_ARGS__)
174 #define err_puts(e, s) i915_error_puts(e, s)
175 
176 static void __i915_printfn_error(struct drm_printer *p, struct va_format *vaf)
177 {
178 	i915_error_vprintf(p->arg, vaf->fmt, *vaf->va);
179 }
180 
181 static inline struct drm_printer
182 i915_error_printer(struct drm_i915_error_state_buf *e)
183 {
184 	struct drm_printer p = {
185 		.printfn = __i915_printfn_error,
186 		.arg = e,
187 	};
188 	return p;
189 }
190 
191 /* single threaded page allocator with a reserved stash for emergencies */
192 static void pool_fini(struct folio_batch *fbatch)
193 {
194 	folio_batch_release(fbatch);
195 }
196 
197 static int pool_refill(struct folio_batch *fbatch, gfp_t gfp)
198 {
199 	while (folio_batch_space(fbatch)) {
200 		struct folio *folio;
201 
202 		folio = folio_alloc(gfp, 0);
203 		if (!folio)
204 			return -ENOMEM;
205 
206 		folio_batch_add(fbatch, folio);
207 	}
208 
209 	return 0;
210 }
211 
212 static int pool_init(struct folio_batch *fbatch, gfp_t gfp)
213 {
214 	int err;
215 
216 	folio_batch_init(fbatch);
217 
218 	err = pool_refill(fbatch, gfp);
219 	if (err)
220 		pool_fini(fbatch);
221 
222 	return err;
223 }
224 
225 static void *pool_alloc(struct folio_batch *fbatch, gfp_t gfp)
226 {
227 	struct folio *folio;
228 
229 	folio = folio_alloc(gfp, 0);
230 	if (!folio && folio_batch_count(fbatch))
231 		folio = fbatch->folios[--fbatch->nr];
232 
233 	return folio ? folio_address(folio) : NULL;
234 }
235 
236 static void pool_free(struct folio_batch *fbatch, void *addr)
237 {
238 	struct folio *folio = virt_to_folio(addr);
239 
240 	if (folio_batch_space(fbatch))
241 		folio_batch_add(fbatch, folio);
242 	else
243 		folio_put(folio);
244 }
245 
246 #ifdef CONFIG_DRM_I915_COMPRESS_ERROR
247 
248 struct i915_vma_compress {
249 	struct folio_batch pool;
250 	struct z_stream_s zstream;
251 	void *tmp;
252 };
253 
254 static bool compress_init(struct i915_vma_compress *c)
255 {
256 	struct z_stream_s *zstream = &c->zstream;
257 
258 	if (pool_init(&c->pool, ALLOW_FAIL))
259 		return false;
260 
261 	zstream->workspace =
262 		kmalloc(zlib_deflate_workspacesize(MAX_WBITS, MAX_MEM_LEVEL),
263 			ALLOW_FAIL);
264 	if (!zstream->workspace) {
265 		pool_fini(&c->pool);
266 		return false;
267 	}
268 
269 	c->tmp = NULL;
270 	if (i915_has_memcpy_from_wc())
271 		c->tmp = pool_alloc(&c->pool, ALLOW_FAIL);
272 
273 	return true;
274 }
275 
276 static bool compress_start(struct i915_vma_compress *c)
277 {
278 	struct z_stream_s *zstream = &c->zstream;
279 	void *workspace = zstream->workspace;
280 
281 	memset(zstream, 0, sizeof(*zstream));
282 	zstream->workspace = workspace;
283 
284 	return zlib_deflateInit(zstream, Z_DEFAULT_COMPRESSION) == Z_OK;
285 }
286 
287 static void *compress_next_page(struct i915_vma_compress *c,
288 				struct i915_vma_coredump *dst)
289 {
290 	void *page_addr;
291 	struct page *page;
292 
293 	page_addr = pool_alloc(&c->pool, ALLOW_FAIL);
294 	if (!page_addr)
295 		return ERR_PTR(-ENOMEM);
296 
297 	page = virt_to_page(page_addr);
298 	list_add_tail(&page->lru, &dst->page_list);
299 	return page_addr;
300 }
301 
302 static int compress_page(struct i915_vma_compress *c,
303 			 void *src,
304 			 struct i915_vma_coredump *dst,
305 			 bool wc)
306 {
307 	struct z_stream_s *zstream = &c->zstream;
308 
309 	zstream->next_in = src;
310 	if (wc && c->tmp && i915_memcpy_from_wc(c->tmp, src, PAGE_SIZE))
311 		zstream->next_in = c->tmp;
312 	zstream->avail_in = PAGE_SIZE;
313 
314 	do {
315 		if (zstream->avail_out == 0) {
316 			zstream->next_out = compress_next_page(c, dst);
317 			if (IS_ERR(zstream->next_out))
318 				return PTR_ERR(zstream->next_out);
319 
320 			zstream->avail_out = PAGE_SIZE;
321 		}
322 
323 		if (zlib_deflate(zstream, Z_NO_FLUSH) != Z_OK)
324 			return -EIO;
325 
326 		cond_resched();
327 	} while (zstream->avail_in);
328 
329 	/* Fallback to uncompressed if we increase size? */
330 	if (0 && zstream->total_out > zstream->total_in)
331 		return -E2BIG;
332 
333 	return 0;
334 }
335 
336 static int compress_flush(struct i915_vma_compress *c,
337 			  struct i915_vma_coredump *dst)
338 {
339 	struct z_stream_s *zstream = &c->zstream;
340 
341 	do {
342 		switch (zlib_deflate(zstream, Z_FINISH)) {
343 		case Z_OK: /* more space requested */
344 			zstream->next_out = compress_next_page(c, dst);
345 			if (IS_ERR(zstream->next_out))
346 				return PTR_ERR(zstream->next_out);
347 
348 			zstream->avail_out = PAGE_SIZE;
349 			break;
350 
351 		case Z_STREAM_END:
352 			goto end;
353 
354 		default: /* any error */
355 			return -EIO;
356 		}
357 	} while (1);
358 
359 end:
360 	memset(zstream->next_out, 0, zstream->avail_out);
361 	dst->unused = zstream->avail_out;
362 	return 0;
363 }
364 
365 static void compress_finish(struct i915_vma_compress *c)
366 {
367 	zlib_deflateEnd(&c->zstream);
368 }
369 
370 static void compress_fini(struct i915_vma_compress *c)
371 {
372 	kfree(c->zstream.workspace);
373 	if (c->tmp)
374 		pool_free(&c->pool, c->tmp);
375 	pool_fini(&c->pool);
376 }
377 
378 static void err_compression_marker(struct drm_i915_error_state_buf *m)
379 {
380 	err_puts(m, ":");
381 }
382 
383 #else
384 
385 struct i915_vma_compress {
386 	struct folio_batch pool;
387 };
388 
389 static bool compress_init(struct i915_vma_compress *c)
390 {
391 	return pool_init(&c->pool, ALLOW_FAIL) == 0;
392 }
393 
394 static bool compress_start(struct i915_vma_compress *c)
395 {
396 	return true;
397 }
398 
399 static int compress_page(struct i915_vma_compress *c,
400 			 void *src,
401 			 struct i915_vma_coredump *dst,
402 			 bool wc)
403 {
404 	void *ptr;
405 
406 	ptr = pool_alloc(&c->pool, ALLOW_FAIL);
407 	if (!ptr)
408 		return -ENOMEM;
409 
410 	if (!(wc && i915_memcpy_from_wc(ptr, src, PAGE_SIZE)))
411 		memcpy(ptr, src, PAGE_SIZE);
412 	list_add_tail(&virt_to_page(ptr)->lru, &dst->page_list);
413 	cond_resched();
414 
415 	return 0;
416 }
417 
418 static int compress_flush(struct i915_vma_compress *c,
419 			  struct i915_vma_coredump *dst)
420 {
421 	return 0;
422 }
423 
424 static void compress_finish(struct i915_vma_compress *c)
425 {
426 }
427 
428 static void compress_fini(struct i915_vma_compress *c)
429 {
430 	pool_fini(&c->pool);
431 }
432 
433 static void err_compression_marker(struct drm_i915_error_state_buf *m)
434 {
435 	err_puts(m, "~");
436 }
437 
438 #endif
439 
440 static void error_print_instdone(struct drm_i915_error_state_buf *m,
441 				 const struct intel_engine_coredump *ee)
442 {
443 	int slice;
444 	int subslice;
445 	int iter;
446 
447 	err_printf(m, "  INSTDONE: 0x%08x\n",
448 		   ee->instdone.instdone);
449 
450 	if (ee->engine->class != RENDER_CLASS || GRAPHICS_VER(m->i915) <= 3)
451 		return;
452 
453 	err_printf(m, "  SC_INSTDONE: 0x%08x\n",
454 		   ee->instdone.slice_common);
455 
456 	if (GRAPHICS_VER(m->i915) <= 6)
457 		return;
458 
459 	for_each_ss_steering(iter, ee->engine->gt, slice, subslice)
460 		err_printf(m, "  SAMPLER_INSTDONE[%d][%d]: 0x%08x\n",
461 			   slice, subslice,
462 			   ee->instdone.sampler[slice][subslice]);
463 
464 	for_each_ss_steering(iter, ee->engine->gt, slice, subslice)
465 		err_printf(m, "  ROW_INSTDONE[%d][%d]: 0x%08x\n",
466 			   slice, subslice,
467 			   ee->instdone.row[slice][subslice]);
468 
469 	if (GRAPHICS_VER(m->i915) < 12)
470 		return;
471 
472 	if (GRAPHICS_VER_FULL(m->i915) >= IP_VER(12, 55)) {
473 		for_each_ss_steering(iter, ee->engine->gt, slice, subslice)
474 			err_printf(m, "  GEOM_SVGUNIT_INSTDONE[%d][%d]: 0x%08x\n",
475 				   slice, subslice,
476 				   ee->instdone.geom_svg[slice][subslice]);
477 	}
478 
479 	err_printf(m, "  SC_INSTDONE_EXTRA: 0x%08x\n",
480 		   ee->instdone.slice_common_extra[0]);
481 	err_printf(m, "  SC_INSTDONE_EXTRA2: 0x%08x\n",
482 		   ee->instdone.slice_common_extra[1]);
483 }
484 
485 static void error_print_request(struct drm_i915_error_state_buf *m,
486 				const char *prefix,
487 				const struct i915_request_coredump *erq)
488 {
489 	if (!erq->seqno)
490 		return;
491 
492 	err_printf(m, "%s pid %d, seqno %8x:%08x%s%s, prio %d, head %08x, tail %08x\n",
493 		   prefix, erq->pid, erq->context, erq->seqno,
494 		   test_bit(DMA_FENCE_FLAG_SIGNALED_BIT,
495 			    &erq->flags) ? "!" : "",
496 		   test_bit(DMA_FENCE_FLAG_ENABLE_SIGNAL_BIT,
497 			    &erq->flags) ? "+" : "",
498 		   erq->sched_attr.priority,
499 		   erq->head, erq->tail);
500 }
501 
502 static void error_print_context(struct drm_i915_error_state_buf *m,
503 				const char *header,
504 				const struct i915_gem_context_coredump *ctx)
505 {
506 	err_printf(m, "%s%s[%d] prio %d, guilty %d active %d, runtime total %lluns, avg %lluns\n",
507 		   header, ctx->comm, ctx->pid, ctx->sched_attr.priority,
508 		   ctx->guilty, ctx->active,
509 		   ctx->total_runtime, ctx->avg_runtime);
510 	err_printf(m, "  context timeline seqno %u\n", ctx->hwsp_seqno);
511 }
512 
513 static struct i915_vma_coredump *
514 __find_vma(struct i915_vma_coredump *vma, const char *name)
515 {
516 	while (vma) {
517 		if (strcmp(vma->name, name) == 0)
518 			return vma;
519 		vma = vma->next;
520 	}
521 
522 	return NULL;
523 }
524 
525 static struct i915_vma_coredump *
526 intel_gpu_error_find_batch(const struct intel_engine_coredump *ee)
527 {
528 	return __find_vma(ee->vma, "batch");
529 }
530 
531 static void error_print_engine(struct drm_i915_error_state_buf *m,
532 			       const struct intel_engine_coredump *ee)
533 {
534 	struct i915_vma_coredump *batch;
535 	int n;
536 
537 	err_printf(m, "%s command stream:\n", ee->engine->name);
538 	err_printf(m, "  CCID:  0x%08x\n", ee->ccid);
539 	err_printf(m, "  START: 0x%08x\n", ee->start);
540 	err_printf(m, "  HEAD:  0x%08x [0x%08x]\n", ee->head, ee->rq_head);
541 	err_printf(m, "  TAIL:  0x%08x [0x%08x, 0x%08x]\n",
542 		   ee->tail, ee->rq_post, ee->rq_tail);
543 	err_printf(m, "  CTL:   0x%08x\n", ee->ctl);
544 	err_printf(m, "  MODE:  0x%08x\n", ee->mode);
545 	err_printf(m, "  HWS:   0x%08x\n", ee->hws);
546 	err_printf(m, "  ACTHD: 0x%08x %08x\n",
547 		   (u32)(ee->acthd>>32), (u32)ee->acthd);
548 	err_printf(m, "  IPEIR: 0x%08x\n", ee->ipeir);
549 	err_printf(m, "  IPEHR: 0x%08x\n", ee->ipehr);
550 	err_printf(m, "  ESR:   0x%08x\n", ee->esr);
551 
552 	error_print_instdone(m, ee);
553 
554 	batch = intel_gpu_error_find_batch(ee);
555 	if (batch) {
556 		u64 start = batch->gtt_offset;
557 		u64 end = start + batch->gtt_size;
558 
559 		err_printf(m, "  batch: [0x%08x_%08x, 0x%08x_%08x]\n",
560 			   upper_32_bits(start), lower_32_bits(start),
561 			   upper_32_bits(end), lower_32_bits(end));
562 	}
563 	if (GRAPHICS_VER(m->i915) >= 4) {
564 		err_printf(m, "  BBADDR: 0x%08x_%08x\n",
565 			   (u32)(ee->bbaddr>>32), (u32)ee->bbaddr);
566 		err_printf(m, "  BB_STATE: 0x%08x\n", ee->bbstate);
567 		err_printf(m, "  INSTPS: 0x%08x\n", ee->instps);
568 	}
569 	err_printf(m, "  INSTPM: 0x%08x\n", ee->instpm);
570 	err_printf(m, "  FADDR: 0x%08x %08x\n", upper_32_bits(ee->faddr),
571 		   lower_32_bits(ee->faddr));
572 	if (GRAPHICS_VER(m->i915) >= 6) {
573 		err_printf(m, "  RC PSMI: 0x%08x\n", ee->rc_psmi);
574 		err_printf(m, "  FAULT_REG: 0x%08x\n", ee->fault_reg);
575 	}
576 	if (GRAPHICS_VER(m->i915) >= 11) {
577 		err_printf(m, "  NOPID: 0x%08x\n", ee->nopid);
578 		err_printf(m, "  EXCC: 0x%08x\n", ee->excc);
579 		err_printf(m, "  CMD_CCTL: 0x%08x\n", ee->cmd_cctl);
580 		err_printf(m, "  CSCMDOP: 0x%08x\n", ee->cscmdop);
581 		err_printf(m, "  CTX_SR_CTL: 0x%08x\n", ee->ctx_sr_ctl);
582 		err_printf(m, "  DMA_FADDR_HI: 0x%08x\n", ee->dma_faddr_hi);
583 		err_printf(m, "  DMA_FADDR_LO: 0x%08x\n", ee->dma_faddr_lo);
584 	}
585 	if (HAS_PPGTT(m->i915)) {
586 		err_printf(m, "  GFX_MODE: 0x%08x\n", ee->vm_info.gfx_mode);
587 
588 		if (GRAPHICS_VER(m->i915) >= 8) {
589 			int i;
590 			for (i = 0; i < 4; i++)
591 				err_printf(m, "  PDP%d: 0x%016llx\n",
592 					   i, ee->vm_info.pdp[i]);
593 		} else {
594 			err_printf(m, "  PP_DIR_BASE: 0x%08x\n",
595 				   ee->vm_info.pp_dir_base);
596 		}
597 	}
598 
599 	for (n = 0; n < ee->num_ports; n++) {
600 		err_printf(m, "  ELSP[%d]:", n);
601 		error_print_request(m, " ", &ee->execlist[n]);
602 	}
603 }
604 
605 void i915_error_printf(struct drm_i915_error_state_buf *e, const char *f, ...)
606 {
607 	va_list args;
608 
609 	va_start(args, f);
610 	i915_error_vprintf(e, f, args);
611 	va_end(args);
612 }
613 
614 static void intel_gpu_error_print_vma(struct drm_i915_error_state_buf *m,
615 				      const struct intel_engine_cs *engine,
616 				      const struct i915_vma_coredump *vma)
617 {
618 	char out[ASCII85_BUFSZ];
619 	struct page *page;
620 
621 	if (!vma)
622 		return;
623 
624 	err_printf(m, "%s --- %s = 0x%08x %08x\n",
625 		   engine ? engine->name : "global", vma->name,
626 		   upper_32_bits(vma->gtt_offset),
627 		   lower_32_bits(vma->gtt_offset));
628 
629 	if (vma->gtt_page_sizes > I915_GTT_PAGE_SIZE_4K)
630 		err_printf(m, "gtt_page_sizes = 0x%08x\n", vma->gtt_page_sizes);
631 
632 	err_compression_marker(m);
633 	list_for_each_entry(page, &vma->page_list, lru) {
634 		int i, len;
635 		const u32 *addr = page_address(page);
636 
637 		len = PAGE_SIZE;
638 		if (page == list_last_entry(&vma->page_list, typeof(*page), lru))
639 			len -= vma->unused;
640 		len = ascii85_encode_len(len);
641 
642 		for (i = 0; i < len; i++)
643 			err_puts(m, ascii85_encode(addr[i], out));
644 	}
645 	err_puts(m, "\n");
646 }
647 
648 static void err_print_capabilities(struct drm_i915_error_state_buf *m,
649 				   struct i915_gpu_coredump *error)
650 {
651 	struct drm_printer p = i915_error_printer(m);
652 
653 	intel_device_info_print(&error->device_info, &error->runtime_info, &p);
654 	intel_display_device_info_print(&error->display_device_info,
655 					&error->display_runtime_info, &p);
656 	intel_driver_caps_print(&error->driver_caps, &p);
657 }
658 
659 static void err_print_params(struct drm_i915_error_state_buf *m,
660 			     const struct i915_params *params)
661 {
662 	struct drm_printer p = i915_error_printer(m);
663 
664 	i915_params_dump(params, &p);
665 	intel_display_params_dump(m->i915, &p);
666 }
667 
668 static void err_print_pciid(struct drm_i915_error_state_buf *m,
669 			    struct drm_i915_private *i915)
670 {
671 	struct pci_dev *pdev = to_pci_dev(i915->drm.dev);
672 
673 	err_printf(m, "PCI ID: 0x%04x\n", pdev->device);
674 	err_printf(m, "PCI Revision: 0x%02x\n", pdev->revision);
675 	err_printf(m, "PCI Subsystem: %04x:%04x\n",
676 		   pdev->subsystem_vendor,
677 		   pdev->subsystem_device);
678 }
679 
680 static void err_print_guc_ctb(struct drm_i915_error_state_buf *m,
681 			      const char *name,
682 			      const struct intel_ctb_coredump *ctb)
683 {
684 	if (!ctb->size)
685 		return;
686 
687 	err_printf(m, "GuC %s CTB: raw: 0x%08X, 0x%08X/%08X, cached: 0x%08X/%08X, desc = 0x%08X, buf = 0x%08X x 0x%08X\n",
688 		   name, ctb->raw_status, ctb->raw_head, ctb->raw_tail,
689 		   ctb->head, ctb->tail, ctb->desc_offset, ctb->cmds_offset, ctb->size);
690 }
691 
692 static void err_print_uc(struct drm_i915_error_state_buf *m,
693 			 const struct intel_uc_coredump *error_uc)
694 {
695 	struct drm_printer p = i915_error_printer(m);
696 
697 	intel_uc_fw_dump(&error_uc->guc_fw, &p);
698 	intel_uc_fw_dump(&error_uc->huc_fw, &p);
699 	err_printf(m, "GuC timestamp: 0x%08x\n", error_uc->guc.timestamp);
700 	intel_gpu_error_print_vma(m, NULL, error_uc->guc.vma_log);
701 	err_printf(m, "GuC CTB fence: %d\n", error_uc->guc.last_fence);
702 	err_print_guc_ctb(m, "Send", error_uc->guc.ctb + 0);
703 	err_print_guc_ctb(m, "Recv", error_uc->guc.ctb + 1);
704 	intel_gpu_error_print_vma(m, NULL, error_uc->guc.vma_ctb);
705 }
706 
707 static void err_free_sgl(struct scatterlist *sgl)
708 {
709 	while (sgl) {
710 		struct scatterlist *sg;
711 
712 		for (sg = sgl; !sg_is_chain(sg); sg++) {
713 			kfree(sg_virt(sg));
714 			if (sg_is_last(sg))
715 				break;
716 		}
717 
718 		sg = sg_is_last(sg) ? NULL : sg_chain_ptr(sg);
719 		free_page((unsigned long)sgl);
720 		sgl = sg;
721 	}
722 }
723 
724 static void err_print_gt_info(struct drm_i915_error_state_buf *m,
725 			      struct intel_gt_coredump *gt)
726 {
727 	struct drm_printer p = i915_error_printer(m);
728 
729 	intel_gt_info_print(&gt->info, &p);
730 	intel_sseu_print_topology(gt->_gt->i915, &gt->info.sseu, &p);
731 }
732 
733 static void err_print_gt_display(struct drm_i915_error_state_buf *m,
734 				 struct intel_gt_coredump *gt)
735 {
736 	err_printf(m, "IER: 0x%08x\n", gt->ier);
737 	err_printf(m, "DERRMR: 0x%08x\n", gt->derrmr);
738 }
739 
740 static void err_print_gt_global_nonguc(struct drm_i915_error_state_buf *m,
741 				       struct intel_gt_coredump *gt)
742 {
743 	int i;
744 
745 	err_printf(m, "GT awake: %s\n", str_yes_no(gt->awake));
746 	err_printf(m, "CS timestamp frequency: %u Hz, %d ns\n",
747 		   gt->clock_frequency, gt->clock_period_ns);
748 	err_printf(m, "EIR: 0x%08x\n", gt->eir);
749 	err_printf(m, "PGTBL_ER: 0x%08x\n", gt->pgtbl_er);
750 
751 	for (i = 0; i < gt->ngtier; i++)
752 		err_printf(m, "GTIER[%d]: 0x%08x\n", i, gt->gtier[i]);
753 }
754 
755 static void err_print_gt_global(struct drm_i915_error_state_buf *m,
756 				struct intel_gt_coredump *gt)
757 {
758 	err_printf(m, "FORCEWAKE: 0x%08x\n", gt->forcewake);
759 
760 	if (IS_GRAPHICS_VER(m->i915, 6, 11)) {
761 		err_printf(m, "ERROR: 0x%08x\n", gt->error);
762 		err_printf(m, "DONE_REG: 0x%08x\n", gt->done_reg);
763 	}
764 
765 	if (GRAPHICS_VER(m->i915) >= 8)
766 		err_printf(m, "FAULT_TLB_DATA: 0x%08x 0x%08x\n",
767 			   gt->fault_data1, gt->fault_data0);
768 
769 	if (GRAPHICS_VER(m->i915) == 7)
770 		err_printf(m, "ERR_INT: 0x%08x\n", gt->err_int);
771 
772 	if (IS_GRAPHICS_VER(m->i915, 8, 11))
773 		err_printf(m, "GTT_CACHE_EN: 0x%08x\n", gt->gtt_cache);
774 
775 	if (GRAPHICS_VER(m->i915) == 12)
776 		err_printf(m, "AUX_ERR_DBG: 0x%08x\n", gt->aux_err);
777 
778 	if (GRAPHICS_VER(m->i915) >= 12) {
779 		int i;
780 
781 		for (i = 0; i < I915_MAX_SFC; i++) {
782 			/*
783 			 * SFC_DONE resides in the VD forcewake domain, so it
784 			 * only exists if the corresponding VCS engine is
785 			 * present.
786 			 */
787 			if ((gt->_gt->info.sfc_mask & BIT(i)) == 0 ||
788 			    !HAS_ENGINE(gt->_gt, _VCS(i * 2)))
789 				continue;
790 
791 			err_printf(m, "  SFC_DONE[%d]: 0x%08x\n", i,
792 				   gt->sfc_done[i]);
793 		}
794 
795 		err_printf(m, "  GAM_DONE: 0x%08x\n", gt->gam_done);
796 	}
797 }
798 
799 static void err_print_gt_fences(struct drm_i915_error_state_buf *m,
800 				struct intel_gt_coredump *gt)
801 {
802 	int i;
803 
804 	for (i = 0; i < gt->nfence; i++)
805 		err_printf(m, "  fence[%d] = %08llx\n", i, gt->fence[i]);
806 }
807 
808 static void err_print_gt_engines(struct drm_i915_error_state_buf *m,
809 				 struct intel_gt_coredump *gt)
810 {
811 	const struct intel_engine_coredump *ee;
812 
813 	for (ee = gt->engine; ee; ee = ee->next) {
814 		const struct i915_vma_coredump *vma;
815 
816 		if (gt->uc && gt->uc->guc.is_guc_capture) {
817 			if (ee->guc_capture_node)
818 				intel_guc_capture_print_engine_node(m, ee);
819 			else
820 				err_printf(m, "  Missing GuC capture node for %s\n",
821 					   ee->engine->name);
822 		} else {
823 			error_print_engine(m, ee);
824 		}
825 
826 		err_printf(m, "  hung: %u\n", ee->hung);
827 		err_printf(m, "  engine reset count: %u\n", ee->reset_count);
828 		error_print_context(m, "  Active context: ", &ee->context);
829 
830 		for (vma = ee->vma; vma; vma = vma->next)
831 			intel_gpu_error_print_vma(m, ee->engine, vma);
832 	}
833 
834 }
835 
836 static void __err_print_to_sgl(struct drm_i915_error_state_buf *m,
837 			       struct i915_gpu_coredump *error)
838 {
839 	struct drm_printer p = i915_error_printer(m);
840 	const struct intel_engine_coredump *ee;
841 	struct timespec64 ts;
842 
843 	if (*error->error_msg)
844 		err_printf(m, "%s\n", error->error_msg);
845 	err_printf(m, "Kernel: %s %s\n",
846 		   init_utsname()->release,
847 		   init_utsname()->machine);
848 	err_printf(m, "Driver: %s\n", DRIVER_DATE);
849 	ts = ktime_to_timespec64(error->time);
850 	err_printf(m, "Time: %lld s %ld us\n",
851 		   (s64)ts.tv_sec, ts.tv_nsec / NSEC_PER_USEC);
852 	ts = ktime_to_timespec64(error->boottime);
853 	err_printf(m, "Boottime: %lld s %ld us\n",
854 		   (s64)ts.tv_sec, ts.tv_nsec / NSEC_PER_USEC);
855 	ts = ktime_to_timespec64(error->uptime);
856 	err_printf(m, "Uptime: %lld s %ld us\n",
857 		   (s64)ts.tv_sec, ts.tv_nsec / NSEC_PER_USEC);
858 	err_printf(m, "Capture: %lu jiffies; %d ms ago\n",
859 		   error->capture, jiffies_to_msecs(jiffies - error->capture));
860 
861 	for (ee = error->gt ? error->gt->engine : NULL; ee; ee = ee->next)
862 		err_printf(m, "Active process (on ring %s): %s [%d]\n",
863 			   ee->engine->name,
864 			   ee->context.comm,
865 			   ee->context.pid);
866 
867 	err_printf(m, "Reset count: %u\n", error->reset_count);
868 	err_printf(m, "Suspend count: %u\n", error->suspend_count);
869 	err_printf(m, "Platform: %s\n", intel_platform_name(error->device_info.platform));
870 	err_printf(m, "Subplatform: 0x%x\n",
871 		   intel_subplatform(&error->runtime_info,
872 				     error->device_info.platform));
873 	err_print_pciid(m, m->i915);
874 
875 	err_printf(m, "IOMMU enabled?: %d\n", error->iommu);
876 
877 	intel_dmc_print_error_state(&p, m->i915);
878 
879 	err_printf(m, "RPM wakelock: %s\n", str_yes_no(error->wakelock));
880 	err_printf(m, "PM suspended: %s\n", str_yes_no(error->suspended));
881 
882 	if (error->gt) {
883 		bool print_guc_capture = false;
884 
885 		if (error->gt->uc && error->gt->uc->guc.is_guc_capture)
886 			print_guc_capture = true;
887 
888 		err_print_gt_display(m, error->gt);
889 		err_print_gt_global_nonguc(m, error->gt);
890 		err_print_gt_fences(m, error->gt);
891 
892 		/*
893 		 * GuC dumped global, eng-class and eng-instance registers together
894 		 * as part of engine state dump so we print in err_print_gt_engines
895 		 */
896 		if (!print_guc_capture)
897 			err_print_gt_global(m, error->gt);
898 
899 		err_print_gt_engines(m, error->gt);
900 
901 		if (error->gt->uc)
902 			err_print_uc(m, error->gt->uc);
903 
904 		err_print_gt_info(m, error->gt);
905 	}
906 
907 	if (error->overlay)
908 		intel_overlay_print_error_state(&p, error->overlay);
909 
910 	err_print_capabilities(m, error);
911 	err_print_params(m, &error->params);
912 }
913 
914 static int err_print_to_sgl(struct i915_gpu_coredump *error)
915 {
916 	struct drm_i915_error_state_buf m;
917 
918 	if (IS_ERR(error))
919 		return PTR_ERR(error);
920 
921 	if (READ_ONCE(error->sgl))
922 		return 0;
923 
924 	memset(&m, 0, sizeof(m));
925 	m.i915 = error->i915;
926 
927 	__err_print_to_sgl(&m, error);
928 
929 	if (m.buf) {
930 		__sg_set_buf(m.cur++, m.buf, m.bytes, m.iter);
931 		m.bytes = 0;
932 		m.buf = NULL;
933 	}
934 	if (m.cur) {
935 		GEM_BUG_ON(m.end < m.cur);
936 		sg_mark_end(m.cur - 1);
937 	}
938 	GEM_BUG_ON(m.sgl && !m.cur);
939 
940 	if (m.err) {
941 		err_free_sgl(m.sgl);
942 		return m.err;
943 	}
944 
945 	if (cmpxchg(&error->sgl, NULL, m.sgl))
946 		err_free_sgl(m.sgl);
947 
948 	return 0;
949 }
950 
951 ssize_t i915_gpu_coredump_copy_to_buffer(struct i915_gpu_coredump *error,
952 					 char *buf, loff_t off, size_t rem)
953 {
954 	struct scatterlist *sg;
955 	size_t count;
956 	loff_t pos;
957 	int err;
958 
959 	if (!error || !rem)
960 		return 0;
961 
962 	err = err_print_to_sgl(error);
963 	if (err)
964 		return err;
965 
966 	sg = READ_ONCE(error->fit);
967 	if (!sg || off < sg->dma_address)
968 		sg = error->sgl;
969 	if (!sg)
970 		return 0;
971 
972 	pos = sg->dma_address;
973 	count = 0;
974 	do {
975 		size_t len, start;
976 
977 		if (sg_is_chain(sg)) {
978 			sg = sg_chain_ptr(sg);
979 			GEM_BUG_ON(sg_is_chain(sg));
980 		}
981 
982 		len = sg->length;
983 		if (pos + len <= off) {
984 			pos += len;
985 			continue;
986 		}
987 
988 		start = sg->offset;
989 		if (pos < off) {
990 			GEM_BUG_ON(off - pos > len);
991 			len -= off - pos;
992 			start += off - pos;
993 			pos = off;
994 		}
995 
996 		len = min(len, rem);
997 		GEM_BUG_ON(!len || len > sg->length);
998 
999 		memcpy(buf, page_address(sg_page(sg)) + start, len);
1000 
1001 		count += len;
1002 		pos += len;
1003 
1004 		buf += len;
1005 		rem -= len;
1006 		if (!rem) {
1007 			WRITE_ONCE(error->fit, sg);
1008 			break;
1009 		}
1010 	} while (!sg_is_last(sg++));
1011 
1012 	return count;
1013 }
1014 
1015 static void i915_vma_coredump_free(struct i915_vma_coredump *vma)
1016 {
1017 	while (vma) {
1018 		struct i915_vma_coredump *next = vma->next;
1019 		struct page *page, *n;
1020 
1021 		list_for_each_entry_safe(page, n, &vma->page_list, lru) {
1022 			list_del_init(&page->lru);
1023 			__free_page(page);
1024 		}
1025 
1026 		kfree(vma);
1027 		vma = next;
1028 	}
1029 }
1030 
1031 static void cleanup_params(struct i915_gpu_coredump *error)
1032 {
1033 	i915_params_free(&error->params);
1034 	intel_display_params_free(&error->display_params);
1035 }
1036 
1037 static void cleanup_uc(struct intel_uc_coredump *uc)
1038 {
1039 	kfree(uc->guc_fw.file_selected.path);
1040 	kfree(uc->huc_fw.file_selected.path);
1041 	kfree(uc->guc_fw.file_wanted.path);
1042 	kfree(uc->huc_fw.file_wanted.path);
1043 	i915_vma_coredump_free(uc->guc.vma_log);
1044 	i915_vma_coredump_free(uc->guc.vma_ctb);
1045 
1046 	kfree(uc);
1047 }
1048 
1049 static void cleanup_gt(struct intel_gt_coredump *gt)
1050 {
1051 	while (gt->engine) {
1052 		struct intel_engine_coredump *ee = gt->engine;
1053 
1054 		gt->engine = ee->next;
1055 
1056 		i915_vma_coredump_free(ee->vma);
1057 		intel_guc_capture_free_node(ee);
1058 		kfree(ee);
1059 	}
1060 
1061 	if (gt->uc)
1062 		cleanup_uc(gt->uc);
1063 
1064 	kfree(gt);
1065 }
1066 
1067 void __i915_gpu_coredump_free(struct kref *error_ref)
1068 {
1069 	struct i915_gpu_coredump *error =
1070 		container_of(error_ref, typeof(*error), ref);
1071 
1072 	while (error->gt) {
1073 		struct intel_gt_coredump *gt = error->gt;
1074 
1075 		error->gt = gt->next;
1076 		cleanup_gt(gt);
1077 	}
1078 
1079 	kfree(error->overlay);
1080 
1081 	cleanup_params(error);
1082 
1083 	err_free_sgl(error->sgl);
1084 	kfree(error);
1085 }
1086 
1087 static struct i915_vma_coredump *
1088 i915_vma_coredump_create(const struct intel_gt *gt,
1089 			 const struct i915_vma_resource *vma_res,
1090 			 struct i915_vma_compress *compress,
1091 			 const char *name)
1092 
1093 {
1094 	struct i915_ggtt *ggtt = gt->ggtt;
1095 	const u64 slot = ggtt->error_capture.start;
1096 	struct i915_vma_coredump *dst;
1097 	struct sgt_iter iter;
1098 	int ret;
1099 
1100 	might_sleep();
1101 
1102 	if (!vma_res || !vma_res->bi.pages || !compress)
1103 		return NULL;
1104 
1105 	dst = kmalloc(sizeof(*dst), ALLOW_FAIL);
1106 	if (!dst)
1107 		return NULL;
1108 
1109 	if (!compress_start(compress)) {
1110 		kfree(dst);
1111 		return NULL;
1112 	}
1113 
1114 	INIT_LIST_HEAD(&dst->page_list);
1115 	strcpy(dst->name, name);
1116 	dst->next = NULL;
1117 
1118 	dst->gtt_offset = vma_res->start;
1119 	dst->gtt_size = vma_res->node_size;
1120 	dst->gtt_page_sizes = vma_res->page_sizes_gtt;
1121 	dst->unused = 0;
1122 
1123 	ret = -EINVAL;
1124 	if (drm_mm_node_allocated(&ggtt->error_capture)) {
1125 		void __iomem *s;
1126 		dma_addr_t dma;
1127 
1128 		for_each_sgt_daddr(dma, iter, vma_res->bi.pages) {
1129 			mutex_lock(&ggtt->error_mutex);
1130 			if (ggtt->vm.raw_insert_page)
1131 				ggtt->vm.raw_insert_page(&ggtt->vm, dma, slot,
1132 							 i915_gem_get_pat_index(gt->i915,
1133 										I915_CACHE_NONE),
1134 							 0);
1135 			else
1136 				ggtt->vm.insert_page(&ggtt->vm, dma, slot,
1137 						     i915_gem_get_pat_index(gt->i915,
1138 									    I915_CACHE_NONE),
1139 						     0);
1140 			mb();
1141 
1142 			s = io_mapping_map_wc(&ggtt->iomap, slot, PAGE_SIZE);
1143 			ret = compress_page(compress,
1144 					    (void  __force *)s, dst,
1145 					    true);
1146 			io_mapping_unmap(s);
1147 
1148 			mb();
1149 			ggtt->vm.clear_range(&ggtt->vm, slot, PAGE_SIZE);
1150 			mutex_unlock(&ggtt->error_mutex);
1151 			if (ret)
1152 				break;
1153 		}
1154 	} else if (vma_res->bi.lmem) {
1155 		struct intel_memory_region *mem = vma_res->mr;
1156 		dma_addr_t dma;
1157 
1158 		for_each_sgt_daddr(dma, iter, vma_res->bi.pages) {
1159 			dma_addr_t offset = dma - mem->region.start;
1160 			void __iomem *s;
1161 
1162 			if (offset + PAGE_SIZE > resource_size(&mem->io)) {
1163 				ret = -EINVAL;
1164 				break;
1165 			}
1166 
1167 			s = io_mapping_map_wc(&mem->iomap, offset, PAGE_SIZE);
1168 			ret = compress_page(compress,
1169 					    (void __force *)s, dst,
1170 					    true);
1171 			io_mapping_unmap(s);
1172 			if (ret)
1173 				break;
1174 		}
1175 	} else {
1176 		struct page *page;
1177 
1178 		for_each_sgt_page(page, iter, vma_res->bi.pages) {
1179 			void *s;
1180 
1181 			drm_clflush_pages(&page, 1);
1182 
1183 			s = kmap_local_page(page);
1184 			ret = compress_page(compress, s, dst, false);
1185 			kunmap_local(s);
1186 
1187 			drm_clflush_pages(&page, 1);
1188 
1189 			if (ret)
1190 				break;
1191 		}
1192 	}
1193 
1194 	if (ret || compress_flush(compress, dst)) {
1195 		struct page *page, *n;
1196 
1197 		list_for_each_entry_safe_reverse(page, n, &dst->page_list, lru) {
1198 			list_del_init(&page->lru);
1199 			pool_free(&compress->pool, page_address(page));
1200 		}
1201 
1202 		kfree(dst);
1203 		dst = NULL;
1204 	}
1205 	compress_finish(compress);
1206 
1207 	return dst;
1208 }
1209 
1210 static void gt_record_fences(struct intel_gt_coredump *gt)
1211 {
1212 	struct i915_ggtt *ggtt = gt->_gt->ggtt;
1213 	struct intel_uncore *uncore = gt->_gt->uncore;
1214 	int i;
1215 
1216 	if (GRAPHICS_VER(uncore->i915) >= 6) {
1217 		for (i = 0; i < ggtt->num_fences; i++)
1218 			gt->fence[i] =
1219 				intel_uncore_read64(uncore,
1220 						    FENCE_REG_GEN6_LO(i));
1221 	} else if (GRAPHICS_VER(uncore->i915) >= 4) {
1222 		for (i = 0; i < ggtt->num_fences; i++)
1223 			gt->fence[i] =
1224 				intel_uncore_read64(uncore,
1225 						    FENCE_REG_965_LO(i));
1226 	} else {
1227 		for (i = 0; i < ggtt->num_fences; i++)
1228 			gt->fence[i] =
1229 				intel_uncore_read(uncore, FENCE_REG(i));
1230 	}
1231 	gt->nfence = i;
1232 }
1233 
1234 static void engine_record_registers(struct intel_engine_coredump *ee)
1235 {
1236 	const struct intel_engine_cs *engine = ee->engine;
1237 	struct drm_i915_private *i915 = engine->i915;
1238 
1239 	if (GRAPHICS_VER(i915) >= 6) {
1240 		ee->rc_psmi = ENGINE_READ(engine, RING_PSMI_CTL);
1241 
1242 		/*
1243 		 * For the media GT, this ring fault register is not replicated,
1244 		 * so don't do multicast/replicated register read/write
1245 		 * operation on it.
1246 		 */
1247 		if (MEDIA_VER(i915) >= 13 && engine->gt->type == GT_MEDIA)
1248 			ee->fault_reg = intel_uncore_read(engine->uncore,
1249 							  XELPMP_RING_FAULT_REG);
1250 		else if (GRAPHICS_VER_FULL(i915) >= IP_VER(12, 55))
1251 			ee->fault_reg = intel_gt_mcr_read_any(engine->gt,
1252 							      XEHP_RING_FAULT_REG);
1253 		else if (GRAPHICS_VER(i915) >= 12)
1254 			ee->fault_reg = intel_uncore_read(engine->uncore,
1255 							  GEN12_RING_FAULT_REG);
1256 		else if (GRAPHICS_VER(i915) >= 8)
1257 			ee->fault_reg = intel_uncore_read(engine->uncore,
1258 							  GEN8_RING_FAULT_REG);
1259 		else
1260 			ee->fault_reg = GEN6_RING_FAULT_REG_READ(engine);
1261 	}
1262 
1263 	if (GRAPHICS_VER(i915) >= 4) {
1264 		ee->esr = ENGINE_READ(engine, RING_ESR);
1265 		ee->faddr = ENGINE_READ(engine, RING_DMA_FADD);
1266 		ee->ipeir = ENGINE_READ(engine, RING_IPEIR);
1267 		ee->ipehr = ENGINE_READ(engine, RING_IPEHR);
1268 		ee->instps = ENGINE_READ(engine, RING_INSTPS);
1269 		ee->bbaddr = ENGINE_READ(engine, RING_BBADDR);
1270 		ee->ccid = ENGINE_READ(engine, CCID);
1271 		if (GRAPHICS_VER(i915) >= 8) {
1272 			ee->faddr |= (u64)ENGINE_READ(engine, RING_DMA_FADD_UDW) << 32;
1273 			ee->bbaddr |= (u64)ENGINE_READ(engine, RING_BBADDR_UDW) << 32;
1274 		}
1275 		ee->bbstate = ENGINE_READ(engine, RING_BBSTATE);
1276 	} else {
1277 		ee->faddr = ENGINE_READ(engine, DMA_FADD_I8XX);
1278 		ee->ipeir = ENGINE_READ(engine, IPEIR);
1279 		ee->ipehr = ENGINE_READ(engine, IPEHR);
1280 	}
1281 
1282 	if (GRAPHICS_VER(i915) >= 11) {
1283 		ee->cmd_cctl = ENGINE_READ(engine, RING_CMD_CCTL);
1284 		ee->cscmdop = ENGINE_READ(engine, RING_CSCMDOP);
1285 		ee->ctx_sr_ctl = ENGINE_READ(engine, RING_CTX_SR_CTL);
1286 		ee->dma_faddr_hi = ENGINE_READ(engine, RING_DMA_FADD_UDW);
1287 		ee->dma_faddr_lo = ENGINE_READ(engine, RING_DMA_FADD);
1288 		ee->nopid = ENGINE_READ(engine, RING_NOPID);
1289 		ee->excc = ENGINE_READ(engine, RING_EXCC);
1290 	}
1291 
1292 	intel_engine_get_instdone(engine, &ee->instdone);
1293 
1294 	ee->instpm = ENGINE_READ(engine, RING_INSTPM);
1295 	ee->acthd = intel_engine_get_active_head(engine);
1296 	ee->start = ENGINE_READ(engine, RING_START);
1297 	ee->head = ENGINE_READ(engine, RING_HEAD);
1298 	ee->tail = ENGINE_READ(engine, RING_TAIL);
1299 	ee->ctl = ENGINE_READ(engine, RING_CTL);
1300 	if (GRAPHICS_VER(i915) > 2)
1301 		ee->mode = ENGINE_READ(engine, RING_MI_MODE);
1302 
1303 	if (!HWS_NEEDS_PHYSICAL(i915)) {
1304 		i915_reg_t mmio;
1305 
1306 		if (GRAPHICS_VER(i915) == 7) {
1307 			switch (engine->id) {
1308 			default:
1309 				MISSING_CASE(engine->id);
1310 				fallthrough;
1311 			case RCS0:
1312 				mmio = RENDER_HWS_PGA_GEN7;
1313 				break;
1314 			case BCS0:
1315 				mmio = BLT_HWS_PGA_GEN7;
1316 				break;
1317 			case VCS0:
1318 				mmio = BSD_HWS_PGA_GEN7;
1319 				break;
1320 			case VECS0:
1321 				mmio = VEBOX_HWS_PGA_GEN7;
1322 				break;
1323 			}
1324 		} else if (GRAPHICS_VER(engine->i915) == 6) {
1325 			mmio = RING_HWS_PGA_GEN6(engine->mmio_base);
1326 		} else {
1327 			/* XXX: gen8 returns to sanity */
1328 			mmio = RING_HWS_PGA(engine->mmio_base);
1329 		}
1330 
1331 		ee->hws = intel_uncore_read(engine->uncore, mmio);
1332 	}
1333 
1334 	ee->reset_count = i915_reset_engine_count(&i915->gpu_error, engine);
1335 
1336 	if (HAS_PPGTT(i915)) {
1337 		int i;
1338 
1339 		ee->vm_info.gfx_mode = ENGINE_READ(engine, RING_MODE_GEN7);
1340 
1341 		if (GRAPHICS_VER(i915) == 6) {
1342 			ee->vm_info.pp_dir_base =
1343 				ENGINE_READ(engine, RING_PP_DIR_BASE_READ);
1344 		} else if (GRAPHICS_VER(i915) == 7) {
1345 			ee->vm_info.pp_dir_base =
1346 				ENGINE_READ(engine, RING_PP_DIR_BASE);
1347 		} else if (GRAPHICS_VER(i915) >= 8) {
1348 			u32 base = engine->mmio_base;
1349 
1350 			for (i = 0; i < 4; i++) {
1351 				ee->vm_info.pdp[i] =
1352 					intel_uncore_read(engine->uncore,
1353 							  GEN8_RING_PDP_UDW(base, i));
1354 				ee->vm_info.pdp[i] <<= 32;
1355 				ee->vm_info.pdp[i] |=
1356 					intel_uncore_read(engine->uncore,
1357 							  GEN8_RING_PDP_LDW(base, i));
1358 			}
1359 		}
1360 	}
1361 }
1362 
1363 static void record_request(const struct i915_request *request,
1364 			   struct i915_request_coredump *erq)
1365 {
1366 	erq->flags = request->fence.flags;
1367 	erq->context = request->fence.context;
1368 	erq->seqno = request->fence.seqno;
1369 	erq->sched_attr = request->sched.attr;
1370 	erq->head = request->head;
1371 	erq->tail = request->tail;
1372 
1373 	erq->pid = 0;
1374 	rcu_read_lock();
1375 	if (!intel_context_is_closed(request->context)) {
1376 		const struct i915_gem_context *ctx;
1377 
1378 		ctx = rcu_dereference(request->context->gem_context);
1379 		if (ctx)
1380 			erq->pid = pid_nr(ctx->pid);
1381 	}
1382 	rcu_read_unlock();
1383 }
1384 
1385 static void engine_record_execlists(struct intel_engine_coredump *ee)
1386 {
1387 	const struct intel_engine_execlists * const el = &ee->engine->execlists;
1388 	struct i915_request * const *port = el->active;
1389 	unsigned int n = 0;
1390 
1391 	while (*port)
1392 		record_request(*port++, &ee->execlist[n++]);
1393 
1394 	ee->num_ports = n;
1395 }
1396 
1397 static bool record_context(struct i915_gem_context_coredump *e,
1398 			   struct intel_context *ce)
1399 {
1400 	struct i915_gem_context *ctx;
1401 	struct task_struct *task;
1402 	bool simulated;
1403 
1404 	rcu_read_lock();
1405 	ctx = rcu_dereference(ce->gem_context);
1406 	if (ctx && !kref_get_unless_zero(&ctx->ref))
1407 		ctx = NULL;
1408 	rcu_read_unlock();
1409 	if (!ctx)
1410 		return true;
1411 
1412 	rcu_read_lock();
1413 	task = pid_task(ctx->pid, PIDTYPE_PID);
1414 	if (task) {
1415 		strcpy(e->comm, task->comm);
1416 		e->pid = task->pid;
1417 	}
1418 	rcu_read_unlock();
1419 
1420 	e->sched_attr = ctx->sched;
1421 	e->guilty = atomic_read(&ctx->guilty_count);
1422 	e->active = atomic_read(&ctx->active_count);
1423 	e->hwsp_seqno = (ce->timeline && ce->timeline->hwsp_seqno) ?
1424 				*ce->timeline->hwsp_seqno : ~0U;
1425 
1426 	e->total_runtime = intel_context_get_total_runtime_ns(ce);
1427 	e->avg_runtime = intel_context_get_avg_runtime_ns(ce);
1428 
1429 	simulated = i915_gem_context_no_error_capture(ctx);
1430 
1431 	i915_gem_context_put(ctx);
1432 	return simulated;
1433 }
1434 
1435 struct intel_engine_capture_vma {
1436 	struct intel_engine_capture_vma *next;
1437 	struct i915_vma_resource *vma_res;
1438 	char name[16];
1439 	bool lockdep_cookie;
1440 };
1441 
1442 static struct intel_engine_capture_vma *
1443 capture_vma_snapshot(struct intel_engine_capture_vma *next,
1444 		     struct i915_vma_resource *vma_res,
1445 		     gfp_t gfp, const char *name)
1446 {
1447 	struct intel_engine_capture_vma *c;
1448 
1449 	if (!vma_res)
1450 		return next;
1451 
1452 	c = kmalloc(sizeof(*c), gfp);
1453 	if (!c)
1454 		return next;
1455 
1456 	if (!i915_vma_resource_hold(vma_res, &c->lockdep_cookie)) {
1457 		kfree(c);
1458 		return next;
1459 	}
1460 
1461 	strcpy(c->name, name);
1462 	c->vma_res = i915_vma_resource_get(vma_res);
1463 
1464 	c->next = next;
1465 	return c;
1466 }
1467 
1468 static struct intel_engine_capture_vma *
1469 capture_vma(struct intel_engine_capture_vma *next,
1470 	    struct i915_vma *vma,
1471 	    const char *name,
1472 	    gfp_t gfp)
1473 {
1474 	if (!vma)
1475 		return next;
1476 
1477 	/*
1478 	 * If the vma isn't pinned, then the vma should be snapshotted
1479 	 * to a struct i915_vma_snapshot at command submission time.
1480 	 * Not here.
1481 	 */
1482 	if (GEM_WARN_ON(!i915_vma_is_pinned(vma)))
1483 		return next;
1484 
1485 	next = capture_vma_snapshot(next, vma->resource, gfp, name);
1486 
1487 	return next;
1488 }
1489 
1490 static struct intel_engine_capture_vma *
1491 capture_user(struct intel_engine_capture_vma *capture,
1492 	     const struct i915_request *rq,
1493 	     gfp_t gfp)
1494 {
1495 	struct i915_capture_list *c;
1496 
1497 	for (c = rq->capture_list; c; c = c->next)
1498 		capture = capture_vma_snapshot(capture, c->vma_res, gfp,
1499 					       "user");
1500 
1501 	return capture;
1502 }
1503 
1504 static void add_vma(struct intel_engine_coredump *ee,
1505 		    struct i915_vma_coredump *vma)
1506 {
1507 	if (vma) {
1508 		vma->next = ee->vma;
1509 		ee->vma = vma;
1510 	}
1511 }
1512 
1513 static struct i915_vma_coredump *
1514 create_vma_coredump(const struct intel_gt *gt, struct i915_vma *vma,
1515 		    const char *name, struct i915_vma_compress *compress)
1516 {
1517 	struct i915_vma_coredump *ret = NULL;
1518 	struct i915_vma_resource *vma_res;
1519 	bool lockdep_cookie;
1520 
1521 	if (!vma)
1522 		return NULL;
1523 
1524 	vma_res = vma->resource;
1525 
1526 	if (i915_vma_resource_hold(vma_res, &lockdep_cookie)) {
1527 		ret = i915_vma_coredump_create(gt, vma_res, compress, name);
1528 		i915_vma_resource_unhold(vma_res, lockdep_cookie);
1529 	}
1530 
1531 	return ret;
1532 }
1533 
1534 static void add_vma_coredump(struct intel_engine_coredump *ee,
1535 			     const struct intel_gt *gt,
1536 			     struct i915_vma *vma,
1537 			     const char *name,
1538 			     struct i915_vma_compress *compress)
1539 {
1540 	add_vma(ee, create_vma_coredump(gt, vma, name, compress));
1541 }
1542 
1543 struct intel_engine_coredump *
1544 intel_engine_coredump_alloc(struct intel_engine_cs *engine, gfp_t gfp, u32 dump_flags)
1545 {
1546 	struct intel_engine_coredump *ee;
1547 
1548 	ee = kzalloc(sizeof(*ee), gfp);
1549 	if (!ee)
1550 		return NULL;
1551 
1552 	ee->engine = engine;
1553 
1554 	if (!(dump_flags & CORE_DUMP_FLAG_IS_GUC_CAPTURE)) {
1555 		engine_record_registers(ee);
1556 		engine_record_execlists(ee);
1557 	}
1558 
1559 	return ee;
1560 }
1561 
1562 static struct intel_engine_capture_vma *
1563 engine_coredump_add_context(struct intel_engine_coredump *ee,
1564 			    struct intel_context *ce,
1565 			    gfp_t gfp)
1566 {
1567 	struct intel_engine_capture_vma *vma = NULL;
1568 
1569 	ee->simulated |= record_context(&ee->context, ce);
1570 	if (ee->simulated)
1571 		return NULL;
1572 
1573 	/*
1574 	 * We need to copy these to an anonymous buffer
1575 	 * as the simplest method to avoid being overwritten
1576 	 * by userspace.
1577 	 */
1578 	vma = capture_vma(vma, ce->ring->vma, "ring", gfp);
1579 	vma = capture_vma(vma, ce->state, "HW context", gfp);
1580 
1581 	return vma;
1582 }
1583 
1584 struct intel_engine_capture_vma *
1585 intel_engine_coredump_add_request(struct intel_engine_coredump *ee,
1586 				  struct i915_request *rq,
1587 				  gfp_t gfp)
1588 {
1589 	struct intel_engine_capture_vma *vma;
1590 
1591 	vma = engine_coredump_add_context(ee, rq->context, gfp);
1592 	if (!vma)
1593 		return NULL;
1594 
1595 	/*
1596 	 * We need to copy these to an anonymous buffer
1597 	 * as the simplest method to avoid being overwritten
1598 	 * by userspace.
1599 	 */
1600 	vma = capture_vma_snapshot(vma, rq->batch_res, gfp, "batch");
1601 	vma = capture_user(vma, rq, gfp);
1602 
1603 	ee->rq_head = rq->head;
1604 	ee->rq_post = rq->postfix;
1605 	ee->rq_tail = rq->tail;
1606 
1607 	return vma;
1608 }
1609 
1610 void
1611 intel_engine_coredump_add_vma(struct intel_engine_coredump *ee,
1612 			      struct intel_engine_capture_vma *capture,
1613 			      struct i915_vma_compress *compress)
1614 {
1615 	const struct intel_engine_cs *engine = ee->engine;
1616 
1617 	while (capture) {
1618 		struct intel_engine_capture_vma *this = capture;
1619 		struct i915_vma_resource *vma_res = this->vma_res;
1620 
1621 		add_vma(ee,
1622 			i915_vma_coredump_create(engine->gt, vma_res,
1623 						 compress, this->name));
1624 
1625 		i915_vma_resource_unhold(vma_res, this->lockdep_cookie);
1626 		i915_vma_resource_put(vma_res);
1627 
1628 		capture = this->next;
1629 		kfree(this);
1630 	}
1631 
1632 	add_vma_coredump(ee, engine->gt, engine->status_page.vma,
1633 			 "HW Status", compress);
1634 
1635 	add_vma_coredump(ee, engine->gt, engine->wa_ctx.vma,
1636 			 "WA context", compress);
1637 }
1638 
1639 static struct intel_engine_coredump *
1640 capture_engine(struct intel_engine_cs *engine,
1641 	       struct i915_vma_compress *compress,
1642 	       u32 dump_flags)
1643 {
1644 	struct intel_engine_capture_vma *capture = NULL;
1645 	struct intel_engine_coredump *ee;
1646 	struct intel_context *ce = NULL;
1647 	struct i915_request *rq = NULL;
1648 
1649 	ee = intel_engine_coredump_alloc(engine, ALLOW_FAIL, dump_flags);
1650 	if (!ee)
1651 		return NULL;
1652 
1653 	intel_engine_get_hung_entity(engine, &ce, &rq);
1654 	if (rq && !i915_request_started(rq))
1655 		drm_info(&engine->gt->i915->drm, "Got hung context on %s with active request %lld:%lld [0x%04X] not yet started\n",
1656 			 engine->name, rq->fence.context, rq->fence.seqno, ce->guc_id.id);
1657 
1658 	if (rq) {
1659 		capture = intel_engine_coredump_add_request(ee, rq, ATOMIC_MAYFAIL);
1660 		i915_request_put(rq);
1661 	} else if (ce) {
1662 		capture = engine_coredump_add_context(ee, ce, ATOMIC_MAYFAIL);
1663 	}
1664 
1665 	if (capture) {
1666 		intel_engine_coredump_add_vma(ee, capture, compress);
1667 
1668 		if (dump_flags & CORE_DUMP_FLAG_IS_GUC_CAPTURE)
1669 			intel_guc_capture_get_matching_node(engine->gt, ee, ce);
1670 	} else {
1671 		kfree(ee);
1672 		ee = NULL;
1673 	}
1674 
1675 	return ee;
1676 }
1677 
1678 static void
1679 gt_record_engines(struct intel_gt_coredump *gt,
1680 		  intel_engine_mask_t engine_mask,
1681 		  struct i915_vma_compress *compress,
1682 		  u32 dump_flags)
1683 {
1684 	struct intel_engine_cs *engine;
1685 	enum intel_engine_id id;
1686 
1687 	for_each_engine(engine, gt->_gt, id) {
1688 		struct intel_engine_coredump *ee;
1689 
1690 		/* Refill our page pool before entering atomic section */
1691 		pool_refill(&compress->pool, ALLOW_FAIL);
1692 
1693 		ee = capture_engine(engine, compress, dump_flags);
1694 		if (!ee)
1695 			continue;
1696 
1697 		ee->hung = engine->mask & engine_mask;
1698 
1699 		gt->simulated |= ee->simulated;
1700 		if (ee->simulated) {
1701 			if (dump_flags & CORE_DUMP_FLAG_IS_GUC_CAPTURE)
1702 				intel_guc_capture_free_node(ee);
1703 			kfree(ee);
1704 			continue;
1705 		}
1706 
1707 		ee->next = gt->engine;
1708 		gt->engine = ee;
1709 	}
1710 }
1711 
1712 static void gt_record_guc_ctb(struct intel_ctb_coredump *saved,
1713 			      const struct intel_guc_ct_buffer *ctb,
1714 			      const void *blob_ptr, struct intel_guc *guc)
1715 {
1716 	if (!ctb || !ctb->desc)
1717 		return;
1718 
1719 	saved->raw_status = ctb->desc->status;
1720 	saved->raw_head = ctb->desc->head;
1721 	saved->raw_tail = ctb->desc->tail;
1722 	saved->head = ctb->head;
1723 	saved->tail = ctb->tail;
1724 	saved->size = ctb->size;
1725 	saved->desc_offset = ((void *)ctb->desc) - blob_ptr;
1726 	saved->cmds_offset = ((void *)ctb->cmds) - blob_ptr;
1727 }
1728 
1729 static struct intel_uc_coredump *
1730 gt_record_uc(struct intel_gt_coredump *gt,
1731 	     struct i915_vma_compress *compress)
1732 {
1733 	const struct intel_uc *uc = &gt->_gt->uc;
1734 	struct intel_uc_coredump *error_uc;
1735 
1736 	error_uc = kzalloc(sizeof(*error_uc), ALLOW_FAIL);
1737 	if (!error_uc)
1738 		return NULL;
1739 
1740 	memcpy(&error_uc->guc_fw, &uc->guc.fw, sizeof(uc->guc.fw));
1741 	memcpy(&error_uc->huc_fw, &uc->huc.fw, sizeof(uc->huc.fw));
1742 
1743 	error_uc->guc_fw.file_selected.path = kstrdup(uc->guc.fw.file_selected.path, ALLOW_FAIL);
1744 	error_uc->huc_fw.file_selected.path = kstrdup(uc->huc.fw.file_selected.path, ALLOW_FAIL);
1745 	error_uc->guc_fw.file_wanted.path = kstrdup(uc->guc.fw.file_wanted.path, ALLOW_FAIL);
1746 	error_uc->huc_fw.file_wanted.path = kstrdup(uc->huc.fw.file_wanted.path, ALLOW_FAIL);
1747 
1748 	/*
1749 	 * Save the GuC log and include a timestamp reference for converting the
1750 	 * log times to system times (in conjunction with the error->boottime and
1751 	 * gt->clock_frequency fields saved elsewhere).
1752 	 */
1753 	error_uc->guc.timestamp = intel_uncore_read(gt->_gt->uncore, GUCPMTIMESTAMP);
1754 	error_uc->guc.vma_log = create_vma_coredump(gt->_gt, uc->guc.log.vma,
1755 						    "GuC log buffer", compress);
1756 	error_uc->guc.vma_ctb = create_vma_coredump(gt->_gt, uc->guc.ct.vma,
1757 						    "GuC CT buffer", compress);
1758 	error_uc->guc.last_fence = uc->guc.ct.requests.last_fence;
1759 	gt_record_guc_ctb(error_uc->guc.ctb + 0, &uc->guc.ct.ctbs.send,
1760 			  uc->guc.ct.ctbs.send.desc, (struct intel_guc *)&uc->guc);
1761 	gt_record_guc_ctb(error_uc->guc.ctb + 1, &uc->guc.ct.ctbs.recv,
1762 			  uc->guc.ct.ctbs.send.desc, (struct intel_guc *)&uc->guc);
1763 
1764 	return error_uc;
1765 }
1766 
1767 /* Capture display registers. */
1768 static void gt_record_display_regs(struct intel_gt_coredump *gt)
1769 {
1770 	struct intel_uncore *uncore = gt->_gt->uncore;
1771 	struct drm_i915_private *i915 = uncore->i915;
1772 
1773 	if (DISPLAY_VER(i915) >= 6 && DISPLAY_VER(i915) < 20)
1774 		gt->derrmr = intel_uncore_read(uncore, DERRMR);
1775 
1776 	if (GRAPHICS_VER(i915) >= 8)
1777 		gt->ier = intel_uncore_read(uncore, GEN8_DE_MISC_IER);
1778 	else if (IS_VALLEYVIEW(i915))
1779 		gt->ier = intel_uncore_read(uncore, VLV_IER);
1780 	else if (HAS_PCH_SPLIT(i915))
1781 		gt->ier = intel_uncore_read(uncore, DEIER);
1782 	else if (GRAPHICS_VER(i915) == 2)
1783 		gt->ier = intel_uncore_read16(uncore, GEN2_IER);
1784 	else
1785 		gt->ier = intel_uncore_read(uncore, GEN2_IER);
1786 }
1787 
1788 /* Capture all other registers that GuC doesn't capture. */
1789 static void gt_record_global_nonguc_regs(struct intel_gt_coredump *gt)
1790 {
1791 	struct intel_uncore *uncore = gt->_gt->uncore;
1792 	struct drm_i915_private *i915 = uncore->i915;
1793 	int i;
1794 
1795 	if (IS_VALLEYVIEW(i915)) {
1796 		gt->gtier[0] = intel_uncore_read(uncore, GTIER);
1797 		gt->ngtier = 1;
1798 	} else if (GRAPHICS_VER(i915) >= 11) {
1799 		gt->gtier[0] =
1800 			intel_uncore_read(uncore,
1801 					  GEN11_RENDER_COPY_INTR_ENABLE);
1802 		gt->gtier[1] =
1803 			intel_uncore_read(uncore, GEN11_VCS_VECS_INTR_ENABLE);
1804 		gt->gtier[2] =
1805 			intel_uncore_read(uncore, GEN11_GUC_SG_INTR_ENABLE);
1806 		gt->gtier[3] =
1807 			intel_uncore_read(uncore,
1808 					  GEN11_GPM_WGBOXPERF_INTR_ENABLE);
1809 		gt->gtier[4] =
1810 			intel_uncore_read(uncore,
1811 					  GEN11_CRYPTO_RSVD_INTR_ENABLE);
1812 		gt->gtier[5] =
1813 			intel_uncore_read(uncore,
1814 					  GEN11_GUNIT_CSME_INTR_ENABLE);
1815 		gt->ngtier = 6;
1816 	} else if (GRAPHICS_VER(i915) >= 8) {
1817 		for (i = 0; i < 4; i++)
1818 			gt->gtier[i] =
1819 				intel_uncore_read(uncore, GEN8_GT_IER(i));
1820 		gt->ngtier = 4;
1821 	} else if (HAS_PCH_SPLIT(i915)) {
1822 		gt->gtier[0] = intel_uncore_read(uncore, GTIER);
1823 		gt->ngtier = 1;
1824 	}
1825 
1826 	gt->eir = intel_uncore_read(uncore, EIR);
1827 	gt->pgtbl_er = intel_uncore_read(uncore, PGTBL_ER);
1828 }
1829 
1830 /*
1831  * Capture all registers that relate to workload submission.
1832  * NOTE: In GuC submission, when GuC resets an engine, it can dump these for us
1833  */
1834 static void gt_record_global_regs(struct intel_gt_coredump *gt)
1835 {
1836 	struct intel_uncore *uncore = gt->_gt->uncore;
1837 	struct drm_i915_private *i915 = uncore->i915;
1838 	int i;
1839 
1840 	/*
1841 	 * General organization
1842 	 * 1. Registers specific to a single generation
1843 	 * 2. Registers which belong to multiple generations
1844 	 * 3. Feature specific registers.
1845 	 * 4. Everything else
1846 	 * Please try to follow the order.
1847 	 */
1848 
1849 	/* 1: Registers specific to a single generation */
1850 	if (IS_VALLEYVIEW(i915))
1851 		gt->forcewake = intel_uncore_read_fw(uncore, FORCEWAKE_VLV);
1852 
1853 	if (GRAPHICS_VER(i915) == 7)
1854 		gt->err_int = intel_uncore_read(uncore, GEN7_ERR_INT);
1855 
1856 	if (GRAPHICS_VER_FULL(i915) >= IP_VER(12, 55)) {
1857 		gt->fault_data0 = intel_gt_mcr_read_any((struct intel_gt *)gt->_gt,
1858 							XEHP_FAULT_TLB_DATA0);
1859 		gt->fault_data1 = intel_gt_mcr_read_any((struct intel_gt *)gt->_gt,
1860 							XEHP_FAULT_TLB_DATA1);
1861 	} else if (GRAPHICS_VER(i915) >= 12) {
1862 		gt->fault_data0 = intel_uncore_read(uncore,
1863 						    GEN12_FAULT_TLB_DATA0);
1864 		gt->fault_data1 = intel_uncore_read(uncore,
1865 						    GEN12_FAULT_TLB_DATA1);
1866 	} else if (GRAPHICS_VER(i915) >= 8) {
1867 		gt->fault_data0 = intel_uncore_read(uncore,
1868 						    GEN8_FAULT_TLB_DATA0);
1869 		gt->fault_data1 = intel_uncore_read(uncore,
1870 						    GEN8_FAULT_TLB_DATA1);
1871 	}
1872 
1873 	if (GRAPHICS_VER(i915) == 6) {
1874 		gt->forcewake = intel_uncore_read_fw(uncore, FORCEWAKE);
1875 		gt->gab_ctl = intel_uncore_read(uncore, GAB_CTL);
1876 		gt->gfx_mode = intel_uncore_read(uncore, GFX_MODE);
1877 	}
1878 
1879 	/* 2: Registers which belong to multiple generations */
1880 	if (GRAPHICS_VER(i915) >= 7)
1881 		gt->forcewake = intel_uncore_read_fw(uncore, FORCEWAKE_MT);
1882 
1883 	if (GRAPHICS_VER(i915) >= 6) {
1884 		if (GRAPHICS_VER(i915) < 12) {
1885 			gt->error = intel_uncore_read(uncore, ERROR_GEN6);
1886 			gt->done_reg = intel_uncore_read(uncore, DONE_REG);
1887 		}
1888 	}
1889 
1890 	/* 3: Feature specific registers */
1891 	if (IS_GRAPHICS_VER(i915, 6, 7)) {
1892 		gt->gam_ecochk = intel_uncore_read(uncore, GAM_ECOCHK);
1893 		gt->gac_eco = intel_uncore_read(uncore, GAC_ECO_BITS);
1894 	}
1895 
1896 	if (IS_GRAPHICS_VER(i915, 8, 11))
1897 		gt->gtt_cache = intel_uncore_read(uncore, HSW_GTT_CACHE_EN);
1898 
1899 	if (GRAPHICS_VER(i915) == 12)
1900 		gt->aux_err = intel_uncore_read(uncore, GEN12_AUX_ERR_DBG);
1901 
1902 	if (GRAPHICS_VER(i915) >= 12) {
1903 		for (i = 0; i < I915_MAX_SFC; i++) {
1904 			/*
1905 			 * SFC_DONE resides in the VD forcewake domain, so it
1906 			 * only exists if the corresponding VCS engine is
1907 			 * present.
1908 			 */
1909 			if ((gt->_gt->info.sfc_mask & BIT(i)) == 0 ||
1910 			    !HAS_ENGINE(gt->_gt, _VCS(i * 2)))
1911 				continue;
1912 
1913 			gt->sfc_done[i] =
1914 				intel_uncore_read(uncore, GEN12_SFC_DONE(i));
1915 		}
1916 
1917 		gt->gam_done = intel_uncore_read(uncore, GEN12_GAM_DONE);
1918 	}
1919 }
1920 
1921 static void gt_record_info(struct intel_gt_coredump *gt)
1922 {
1923 	memcpy(&gt->info, &gt->_gt->info, sizeof(struct intel_gt_info));
1924 	gt->clock_frequency = gt->_gt->clock_frequency;
1925 	gt->clock_period_ns = gt->_gt->clock_period_ns;
1926 }
1927 
1928 /*
1929  * Generate a semi-unique error code. The code is not meant to have meaning, The
1930  * code's only purpose is to try to prevent false duplicated bug reports by
1931  * grossly estimating a GPU error state.
1932  *
1933  * TODO Ideally, hashing the batchbuffer would be a very nice way to determine
1934  * the hang if we could strip the GTT offset information from it.
1935  *
1936  * It's only a small step better than a random number in its current form.
1937  */
1938 static u32 generate_ecode(const struct intel_engine_coredump *ee)
1939 {
1940 	/*
1941 	 * IPEHR would be an ideal way to detect errors, as it's the gross
1942 	 * measure of "the command that hung." However, has some very common
1943 	 * synchronization commands which almost always appear in the case
1944 	 * strictly a client bug. Use instdone to differentiate those some.
1945 	 */
1946 	return ee ? ee->ipehr ^ ee->instdone.instdone : 0;
1947 }
1948 
1949 static const char *error_msg(struct i915_gpu_coredump *error)
1950 {
1951 	struct intel_engine_coredump *first = NULL;
1952 	unsigned int hung_classes = 0;
1953 	struct intel_gt_coredump *gt;
1954 	int len;
1955 
1956 	for (gt = error->gt; gt; gt = gt->next) {
1957 		struct intel_engine_coredump *cs;
1958 
1959 		for (cs = gt->engine; cs; cs = cs->next) {
1960 			if (cs->hung) {
1961 				hung_classes |= BIT(cs->engine->uabi_class);
1962 				if (!first)
1963 					first = cs;
1964 			}
1965 		}
1966 	}
1967 
1968 	len = scnprintf(error->error_msg, sizeof(error->error_msg),
1969 			"GPU HANG: ecode %d:%x:%08x",
1970 			GRAPHICS_VER(error->i915), hung_classes,
1971 			generate_ecode(first));
1972 	if (first && first->context.pid) {
1973 		/* Just show the first executing process, more is confusing */
1974 		len += scnprintf(error->error_msg + len,
1975 				 sizeof(error->error_msg) - len,
1976 				 ", in %s [%d]",
1977 				 first->context.comm, first->context.pid);
1978 	}
1979 
1980 	return error->error_msg;
1981 }
1982 
1983 static void capture_gen(struct i915_gpu_coredump *error)
1984 {
1985 	struct drm_i915_private *i915 = error->i915;
1986 
1987 	error->wakelock = atomic_read(&i915->runtime_pm.wakeref_count);
1988 	error->suspended = pm_runtime_suspended(i915->drm.dev);
1989 
1990 	error->iommu = i915_vtd_active(i915);
1991 	error->reset_count = i915_reset_count(&i915->gpu_error);
1992 	error->suspend_count = i915->suspend_count;
1993 
1994 	i915_params_copy(&error->params, &i915->params);
1995 	intel_display_params_copy(&error->display_params);
1996 	memcpy(&error->device_info,
1997 	       INTEL_INFO(i915),
1998 	       sizeof(error->device_info));
1999 	memcpy(&error->runtime_info,
2000 	       RUNTIME_INFO(i915),
2001 	       sizeof(error->runtime_info));
2002 	memcpy(&error->display_device_info, DISPLAY_INFO(i915),
2003 	       sizeof(error->display_device_info));
2004 	memcpy(&error->display_runtime_info, DISPLAY_RUNTIME_INFO(i915),
2005 	       sizeof(error->display_runtime_info));
2006 	error->driver_caps = i915->caps;
2007 }
2008 
2009 struct i915_gpu_coredump *
2010 i915_gpu_coredump_alloc(struct drm_i915_private *i915, gfp_t gfp)
2011 {
2012 	struct i915_gpu_coredump *error;
2013 
2014 	if (!i915->params.error_capture)
2015 		return NULL;
2016 
2017 	error = kzalloc(sizeof(*error), gfp);
2018 	if (!error)
2019 		return NULL;
2020 
2021 	kref_init(&error->ref);
2022 	error->i915 = i915;
2023 
2024 	error->time = ktime_get_real();
2025 	error->boottime = ktime_get_boottime();
2026 	error->uptime = ktime_sub(ktime_get(), to_gt(i915)->last_init_time);
2027 	error->capture = jiffies;
2028 
2029 	capture_gen(error);
2030 
2031 	return error;
2032 }
2033 
2034 #define DAY_AS_SECONDS(x) (24 * 60 * 60 * (x))
2035 
2036 struct intel_gt_coredump *
2037 intel_gt_coredump_alloc(struct intel_gt *gt, gfp_t gfp, u32 dump_flags)
2038 {
2039 	struct intel_gt_coredump *gc;
2040 
2041 	gc = kzalloc(sizeof(*gc), gfp);
2042 	if (!gc)
2043 		return NULL;
2044 
2045 	gc->_gt = gt;
2046 	gc->awake = intel_gt_pm_is_awake(gt);
2047 
2048 	gt_record_display_regs(gc);
2049 	gt_record_global_nonguc_regs(gc);
2050 
2051 	/*
2052 	 * GuC dumps global, eng-class and eng-instance registers
2053 	 * (that can change as part of engine state during execution)
2054 	 * before an engine is reset due to a hung context.
2055 	 * GuC captures and reports all three groups of registers
2056 	 * together as a single set before the engine is reset.
2057 	 * Thus, if GuC triggered the context reset we retrieve
2058 	 * the register values as part of gt_record_engines.
2059 	 */
2060 	if (!(dump_flags & CORE_DUMP_FLAG_IS_GUC_CAPTURE))
2061 		gt_record_global_regs(gc);
2062 
2063 	gt_record_fences(gc);
2064 
2065 	return gc;
2066 }
2067 
2068 struct i915_vma_compress *
2069 i915_vma_capture_prepare(struct intel_gt_coredump *gt)
2070 {
2071 	struct i915_vma_compress *compress;
2072 
2073 	compress = kmalloc(sizeof(*compress), ALLOW_FAIL);
2074 	if (!compress)
2075 		return NULL;
2076 
2077 	if (!compress_init(compress)) {
2078 		kfree(compress);
2079 		return NULL;
2080 	}
2081 
2082 	return compress;
2083 }
2084 
2085 void i915_vma_capture_finish(struct intel_gt_coredump *gt,
2086 			     struct i915_vma_compress *compress)
2087 {
2088 	if (!compress)
2089 		return;
2090 
2091 	compress_fini(compress);
2092 	kfree(compress);
2093 }
2094 
2095 static struct i915_gpu_coredump *
2096 __i915_gpu_coredump(struct intel_gt *gt, intel_engine_mask_t engine_mask, u32 dump_flags)
2097 {
2098 	struct drm_i915_private *i915 = gt->i915;
2099 	struct i915_gpu_coredump *error;
2100 
2101 	/* Check if GPU capture has been disabled */
2102 	error = READ_ONCE(i915->gpu_error.first_error);
2103 	if (IS_ERR(error))
2104 		return error;
2105 
2106 	error = i915_gpu_coredump_alloc(i915, ALLOW_FAIL);
2107 	if (!error)
2108 		return ERR_PTR(-ENOMEM);
2109 
2110 	error->gt = intel_gt_coredump_alloc(gt, ALLOW_FAIL, dump_flags);
2111 	if (error->gt) {
2112 		struct i915_vma_compress *compress;
2113 
2114 		compress = i915_vma_capture_prepare(error->gt);
2115 		if (!compress) {
2116 			kfree(error->gt);
2117 			kfree(error);
2118 			return ERR_PTR(-ENOMEM);
2119 		}
2120 
2121 		if (INTEL_INFO(i915)->has_gt_uc) {
2122 			error->gt->uc = gt_record_uc(error->gt, compress);
2123 			if (error->gt->uc) {
2124 				if (dump_flags & CORE_DUMP_FLAG_IS_GUC_CAPTURE)
2125 					error->gt->uc->guc.is_guc_capture = true;
2126 				else
2127 					GEM_BUG_ON(error->gt->uc->guc.is_guc_capture);
2128 			}
2129 		}
2130 
2131 		gt_record_info(error->gt);
2132 		gt_record_engines(error->gt, engine_mask, compress, dump_flags);
2133 
2134 
2135 		i915_vma_capture_finish(error->gt, compress);
2136 
2137 		error->simulated |= error->gt->simulated;
2138 	}
2139 
2140 	error->overlay = intel_overlay_capture_error_state(i915);
2141 
2142 	return error;
2143 }
2144 
2145 static struct i915_gpu_coredump *
2146 i915_gpu_coredump(struct intel_gt *gt, intel_engine_mask_t engine_mask, u32 dump_flags)
2147 {
2148 	static DEFINE_MUTEX(capture_mutex);
2149 	int ret = mutex_lock_interruptible(&capture_mutex);
2150 	struct i915_gpu_coredump *dump;
2151 
2152 	if (ret)
2153 		return ERR_PTR(ret);
2154 
2155 	dump = __i915_gpu_coredump(gt, engine_mask, dump_flags);
2156 	mutex_unlock(&capture_mutex);
2157 
2158 	return dump;
2159 }
2160 
2161 void i915_error_state_store(struct i915_gpu_coredump *error)
2162 {
2163 	struct drm_i915_private *i915;
2164 	static bool warned;
2165 
2166 	if (IS_ERR_OR_NULL(error))
2167 		return;
2168 
2169 	i915 = error->i915;
2170 	drm_info(&i915->drm, "%s\n", error_msg(error));
2171 
2172 	if (error->simulated ||
2173 	    cmpxchg(&i915->gpu_error.first_error, NULL, error))
2174 		return;
2175 
2176 	i915_gpu_coredump_get(error);
2177 
2178 	if (!xchg(&warned, true) &&
2179 	    ktime_get_real_seconds() - DRIVER_TIMESTAMP < DAY_AS_SECONDS(180)) {
2180 		pr_info("GPU hangs can indicate a bug anywhere in the entire gfx stack, including userspace.\n");
2181 		pr_info("Please file a _new_ bug report at https://gitlab.freedesktop.org/drm/intel/issues/new.\n");
2182 		pr_info("Please see https://drm.pages.freedesktop.org/intel-docs/how-to-file-i915-bugs.html for details.\n");
2183 		pr_info("drm/i915 developers can then reassign to the right component if it's not a kernel issue.\n");
2184 		pr_info("The GPU crash dump is required to analyze GPU hangs, so please always attach it.\n");
2185 		pr_info("GPU crash dump saved to /sys/class/drm/card%d/error\n",
2186 			i915->drm.primary->index);
2187 	}
2188 }
2189 
2190 /**
2191  * i915_capture_error_state - capture an error record for later analysis
2192  * @gt: intel_gt which originated the hang
2193  * @engine_mask: hung engines
2194  * @dump_flags: dump flags
2195  *
2196  * Should be called when an error is detected (either a hang or an error
2197  * interrupt) to capture error state from the time of the error.  Fills
2198  * out a structure which becomes available in debugfs for user level tools
2199  * to pick up.
2200  */
2201 void i915_capture_error_state(struct intel_gt *gt,
2202 			      intel_engine_mask_t engine_mask, u32 dump_flags)
2203 {
2204 	struct i915_gpu_coredump *error;
2205 
2206 	error = i915_gpu_coredump(gt, engine_mask, dump_flags);
2207 	if (IS_ERR(error)) {
2208 		cmpxchg(&gt->i915->gpu_error.first_error, NULL, error);
2209 		return;
2210 	}
2211 
2212 	i915_error_state_store(error);
2213 	i915_gpu_coredump_put(error);
2214 }
2215 
2216 static struct i915_gpu_coredump *
2217 i915_first_error_state(struct drm_i915_private *i915)
2218 {
2219 	struct i915_gpu_coredump *error;
2220 
2221 	spin_lock_irq(&i915->gpu_error.lock);
2222 	error = i915->gpu_error.first_error;
2223 	if (!IS_ERR_OR_NULL(error))
2224 		i915_gpu_coredump_get(error);
2225 	spin_unlock_irq(&i915->gpu_error.lock);
2226 
2227 	return error;
2228 }
2229 
2230 void i915_reset_error_state(struct drm_i915_private *i915)
2231 {
2232 	struct i915_gpu_coredump *error;
2233 
2234 	spin_lock_irq(&i915->gpu_error.lock);
2235 	error = i915->gpu_error.first_error;
2236 	if (error != ERR_PTR(-ENODEV)) /* if disabled, always disabled */
2237 		i915->gpu_error.first_error = NULL;
2238 	spin_unlock_irq(&i915->gpu_error.lock);
2239 
2240 	if (!IS_ERR_OR_NULL(error))
2241 		i915_gpu_coredump_put(error);
2242 }
2243 
2244 void i915_disable_error_state(struct drm_i915_private *i915, int err)
2245 {
2246 	spin_lock_irq(&i915->gpu_error.lock);
2247 	if (!i915->gpu_error.first_error)
2248 		i915->gpu_error.first_error = ERR_PTR(err);
2249 	spin_unlock_irq(&i915->gpu_error.lock);
2250 }
2251 
2252 #if IS_ENABLED(CONFIG_DRM_I915_DEBUG_GEM)
2253 void intel_klog_error_capture(struct intel_gt *gt,
2254 			      intel_engine_mask_t engine_mask)
2255 {
2256 	static int g_count;
2257 	struct drm_i915_private *i915 = gt->i915;
2258 	struct i915_gpu_coredump *error;
2259 	intel_wakeref_t wakeref;
2260 	size_t buf_size = PAGE_SIZE * 128;
2261 	size_t pos_err;
2262 	char *buf, *ptr, *next;
2263 	int l_count = g_count++;
2264 	int line = 0;
2265 
2266 	/* Can't allocate memory during a reset */
2267 	if (test_bit(I915_RESET_BACKOFF, &gt->reset.flags)) {
2268 		drm_err(&gt->i915->drm, "[Capture/%d.%d] Inside GT reset, skipping error capture :(\n",
2269 			l_count, line++);
2270 		return;
2271 	}
2272 
2273 	error = READ_ONCE(i915->gpu_error.first_error);
2274 	if (error) {
2275 		drm_err(&i915->drm, "[Capture/%d.%d] Clearing existing error capture first...\n",
2276 			l_count, line++);
2277 		i915_reset_error_state(i915);
2278 	}
2279 
2280 	with_intel_runtime_pm(&i915->runtime_pm, wakeref)
2281 		error = i915_gpu_coredump(gt, engine_mask, CORE_DUMP_FLAG_NONE);
2282 
2283 	if (IS_ERR(error)) {
2284 		drm_err(&i915->drm, "[Capture/%d.%d] Failed to capture error capture: %ld!\n",
2285 			l_count, line++, PTR_ERR(error));
2286 		return;
2287 	}
2288 
2289 	buf = kvmalloc(buf_size, GFP_KERNEL);
2290 	if (!buf) {
2291 		drm_err(&i915->drm, "[Capture/%d.%d] Failed to allocate buffer for error capture!\n",
2292 			l_count, line++);
2293 		i915_gpu_coredump_put(error);
2294 		return;
2295 	}
2296 
2297 	drm_info(&i915->drm, "[Capture/%d.%d] Dumping i915 error capture for %ps...\n",
2298 		 l_count, line++, __builtin_return_address(0));
2299 
2300 	/* Largest string length safe to print via dmesg */
2301 #	define MAX_CHUNK	800
2302 
2303 	pos_err = 0;
2304 	while (1) {
2305 		ssize_t got = i915_gpu_coredump_copy_to_buffer(error, buf, pos_err, buf_size - 1);
2306 
2307 		if (got <= 0)
2308 			break;
2309 
2310 		buf[got] = 0;
2311 		pos_err += got;
2312 
2313 		ptr = buf;
2314 		while (got > 0) {
2315 			size_t count;
2316 			char tag[2];
2317 
2318 			next = strnchr(ptr, got, '\n');
2319 			if (next) {
2320 				count = next - ptr;
2321 				*next = 0;
2322 				tag[0] = '>';
2323 				tag[1] = '<';
2324 			} else {
2325 				count = got;
2326 				tag[0] = '}';
2327 				tag[1] = '{';
2328 			}
2329 
2330 			if (count > MAX_CHUNK) {
2331 				size_t pos;
2332 				char *ptr2 = ptr;
2333 
2334 				for (pos = MAX_CHUNK; pos < count; pos += MAX_CHUNK) {
2335 					char chr = ptr[pos];
2336 
2337 					ptr[pos] = 0;
2338 					drm_info(&i915->drm, "[Capture/%d.%d] }%s{\n",
2339 						 l_count, line++, ptr2);
2340 					ptr[pos] = chr;
2341 					ptr2 = ptr + pos;
2342 
2343 					/*
2344 					 * If spewing large amounts of data via a serial console,
2345 					 * this can be a very slow process. So be friendly and try
2346 					 * not to cause 'softlockup on CPU' problems.
2347 					 */
2348 					cond_resched();
2349 				}
2350 
2351 				if (ptr2 < (ptr + count))
2352 					drm_info(&i915->drm, "[Capture/%d.%d] %c%s%c\n",
2353 						 l_count, line++, tag[0], ptr2, tag[1]);
2354 				else if (tag[0] == '>')
2355 					drm_info(&i915->drm, "[Capture/%d.%d] ><\n",
2356 						 l_count, line++);
2357 			} else {
2358 				drm_info(&i915->drm, "[Capture/%d.%d] %c%s%c\n",
2359 					 l_count, line++, tag[0], ptr, tag[1]);
2360 			}
2361 
2362 			ptr = next;
2363 			got -= count;
2364 			if (next) {
2365 				ptr++;
2366 				got--;
2367 			}
2368 
2369 			/* As above. */
2370 			cond_resched();
2371 		}
2372 
2373 		if (got)
2374 			drm_info(&i915->drm, "[Capture/%d.%d] Got %zd bytes remaining!\n",
2375 				 l_count, line++, got);
2376 	}
2377 
2378 	kvfree(buf);
2379 
2380 	drm_info(&i915->drm, "[Capture/%d.%d] Dumped %zd bytes\n", l_count, line++, pos_err);
2381 }
2382 #endif
2383 
2384 static ssize_t gpu_state_read(struct file *file, char __user *ubuf,
2385 			      size_t count, loff_t *pos)
2386 {
2387 	struct i915_gpu_coredump *error;
2388 	ssize_t ret;
2389 	void *buf;
2390 
2391 	error = file->private_data;
2392 	if (!error)
2393 		return 0;
2394 
2395 	/* Bounce buffer required because of kernfs __user API convenience. */
2396 	buf = kmalloc(count, GFP_KERNEL);
2397 	if (!buf)
2398 		return -ENOMEM;
2399 
2400 	ret = i915_gpu_coredump_copy_to_buffer(error, buf, *pos, count);
2401 	if (ret <= 0)
2402 		goto out;
2403 
2404 	if (!copy_to_user(ubuf, buf, ret))
2405 		*pos += ret;
2406 	else
2407 		ret = -EFAULT;
2408 
2409 out:
2410 	kfree(buf);
2411 	return ret;
2412 }
2413 
2414 static int gpu_state_release(struct inode *inode, struct file *file)
2415 {
2416 	i915_gpu_coredump_put(file->private_data);
2417 	return 0;
2418 }
2419 
2420 static int i915_gpu_info_open(struct inode *inode, struct file *file)
2421 {
2422 	struct drm_i915_private *i915 = inode->i_private;
2423 	struct i915_gpu_coredump *gpu;
2424 	intel_wakeref_t wakeref;
2425 
2426 	gpu = NULL;
2427 	with_intel_runtime_pm(&i915->runtime_pm, wakeref)
2428 		gpu = i915_gpu_coredump(to_gt(i915), ALL_ENGINES, CORE_DUMP_FLAG_NONE);
2429 
2430 	if (IS_ERR(gpu))
2431 		return PTR_ERR(gpu);
2432 
2433 	file->private_data = gpu;
2434 	return 0;
2435 }
2436 
2437 static const struct file_operations i915_gpu_info_fops = {
2438 	.owner = THIS_MODULE,
2439 	.open = i915_gpu_info_open,
2440 	.read = gpu_state_read,
2441 	.llseek = default_llseek,
2442 	.release = gpu_state_release,
2443 };
2444 
2445 static ssize_t
2446 i915_error_state_write(struct file *filp,
2447 		       const char __user *ubuf,
2448 		       size_t cnt,
2449 		       loff_t *ppos)
2450 {
2451 	struct i915_gpu_coredump *error = filp->private_data;
2452 
2453 	if (!error)
2454 		return 0;
2455 
2456 	drm_dbg(&error->i915->drm, "Resetting error state\n");
2457 	i915_reset_error_state(error->i915);
2458 
2459 	return cnt;
2460 }
2461 
2462 static int i915_error_state_open(struct inode *inode, struct file *file)
2463 {
2464 	struct i915_gpu_coredump *error;
2465 
2466 	error = i915_first_error_state(inode->i_private);
2467 	if (IS_ERR(error))
2468 		return PTR_ERR(error);
2469 
2470 	file->private_data  = error;
2471 	return 0;
2472 }
2473 
2474 static const struct file_operations i915_error_state_fops = {
2475 	.owner = THIS_MODULE,
2476 	.open = i915_error_state_open,
2477 	.read = gpu_state_read,
2478 	.write = i915_error_state_write,
2479 	.llseek = default_llseek,
2480 	.release = gpu_state_release,
2481 };
2482 
2483 void i915_gpu_error_debugfs_register(struct drm_i915_private *i915)
2484 {
2485 	struct drm_minor *minor = i915->drm.primary;
2486 
2487 	debugfs_create_file("i915_error_state", 0644, minor->debugfs_root, i915,
2488 			    &i915_error_state_fops);
2489 	debugfs_create_file("i915_gpu_info", 0644, minor->debugfs_root, i915,
2490 			    &i915_gpu_info_fops);
2491 }
2492 
2493 static ssize_t error_state_read(struct file *filp, struct kobject *kobj,
2494 				struct bin_attribute *attr, char *buf,
2495 				loff_t off, size_t count)
2496 {
2497 
2498 	struct device *kdev = kobj_to_dev(kobj);
2499 	struct drm_i915_private *i915 = kdev_minor_to_i915(kdev);
2500 	struct i915_gpu_coredump *gpu;
2501 	ssize_t ret = 0;
2502 
2503 	/*
2504 	 * FIXME: Concurrent clients triggering resets and reading + clearing
2505 	 * dumps can cause inconsistent sysfs reads when a user calls in with a
2506 	 * non-zero offset to complete a prior partial read but the
2507 	 * gpu_coredump has been cleared or replaced.
2508 	 */
2509 
2510 	gpu = i915_first_error_state(i915);
2511 	if (IS_ERR(gpu)) {
2512 		ret = PTR_ERR(gpu);
2513 	} else if (gpu) {
2514 		ret = i915_gpu_coredump_copy_to_buffer(gpu, buf, off, count);
2515 		i915_gpu_coredump_put(gpu);
2516 	} else {
2517 		const char *str = "No error state collected\n";
2518 		size_t len = strlen(str);
2519 
2520 		if (off < len) {
2521 			ret = min_t(size_t, count, len - off);
2522 			memcpy(buf, str + off, ret);
2523 		}
2524 	}
2525 
2526 	return ret;
2527 }
2528 
2529 static ssize_t error_state_write(struct file *file, struct kobject *kobj,
2530 				 struct bin_attribute *attr, char *buf,
2531 				 loff_t off, size_t count)
2532 {
2533 	struct device *kdev = kobj_to_dev(kobj);
2534 	struct drm_i915_private *dev_priv = kdev_minor_to_i915(kdev);
2535 
2536 	drm_dbg(&dev_priv->drm, "Resetting error state\n");
2537 	i915_reset_error_state(dev_priv);
2538 
2539 	return count;
2540 }
2541 
2542 static const struct bin_attribute error_state_attr = {
2543 	.attr.name = "error",
2544 	.attr.mode = S_IRUSR | S_IWUSR,
2545 	.size = 0,
2546 	.read = error_state_read,
2547 	.write = error_state_write,
2548 };
2549 
2550 void i915_gpu_error_sysfs_setup(struct drm_i915_private *i915)
2551 {
2552 	struct device *kdev = i915->drm.primary->kdev;
2553 
2554 	if (sysfs_create_bin_file(&kdev->kobj, &error_state_attr))
2555 		drm_err(&i915->drm, "error_state sysfs setup failed\n");
2556 }
2557 
2558 void i915_gpu_error_sysfs_teardown(struct drm_i915_private *i915)
2559 {
2560 	struct device *kdev = i915->drm.primary->kdev;
2561 
2562 	sysfs_remove_bin_file(&kdev->kobj, &error_state_attr);
2563 }
2564