xref: /linux/drivers/gpu/drm/i915/i915_gpu_error.c (revision ae22a94997b8a03dcb3c922857c203246711f9d4)
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/highmem.h>
32 #include <linux/nmi.h>
33 #include <linux/pagevec.h>
34 #include <linux/scatterlist.h>
35 #include <linux/string_helpers.h>
36 #include <linux/utsname.h>
37 #include <linux/zlib.h>
38 
39 #include <drm/drm_cache.h>
40 #include <drm/drm_print.h>
41 
42 #include "display/intel_dmc.h"
43 #include "display/intel_overlay.h"
44 
45 #include "gem/i915_gem_context.h"
46 #include "gem/i915_gem_lmem.h"
47 #include "gt/intel_engine_regs.h"
48 #include "gt/intel_gt.h"
49 #include "gt/intel_gt_mcr.h"
50 #include "gt/intel_gt_pm.h"
51 #include "gt/intel_gt_regs.h"
52 #include "gt/uc/intel_guc_capture.h"
53 
54 #include "i915_driver.h"
55 #include "i915_drv.h"
56 #include "i915_gpu_error.h"
57 #include "i915_memcpy.h"
58 #include "i915_reg.h"
59 #include "i915_scatterlist.h"
60 #include "i915_sysfs.h"
61 #include "i915_utils.h"
62 
63 #define ALLOW_FAIL (__GFP_KSWAPD_RECLAIM | __GFP_RETRY_MAYFAIL | __GFP_NOWARN)
64 #define ATOMIC_MAYFAIL (GFP_ATOMIC | __GFP_NOWARN)
65 
66 static void __sg_set_buf(struct scatterlist *sg,
67 			 void *addr, unsigned int len, loff_t it)
68 {
69 	sg->page_link = (unsigned long)virt_to_page(addr);
70 	sg->offset = offset_in_page(addr);
71 	sg->length = len;
72 	sg->dma_address = it;
73 }
74 
75 static bool __i915_error_grow(struct drm_i915_error_state_buf *e, size_t len)
76 {
77 	if (!len)
78 		return false;
79 
80 	if (e->bytes + len + 1 <= e->size)
81 		return true;
82 
83 	if (e->bytes) {
84 		__sg_set_buf(e->cur++, e->buf, e->bytes, e->iter);
85 		e->iter += e->bytes;
86 		e->buf = NULL;
87 		e->bytes = 0;
88 	}
89 
90 	if (e->cur == e->end) {
91 		struct scatterlist *sgl;
92 
93 		sgl = (typeof(sgl))__get_free_page(ALLOW_FAIL);
94 		if (!sgl) {
95 			e->err = -ENOMEM;
96 			return false;
97 		}
98 
99 		if (e->cur) {
100 			e->cur->offset = 0;
101 			e->cur->length = 0;
102 			e->cur->page_link =
103 				(unsigned long)sgl | SG_CHAIN;
104 		} else {
105 			e->sgl = sgl;
106 		}
107 
108 		e->cur = sgl;
109 		e->end = sgl + SG_MAX_SINGLE_ALLOC - 1;
110 	}
111 
112 	e->size = ALIGN(len + 1, SZ_64K);
113 	e->buf = kmalloc(e->size, ALLOW_FAIL);
114 	if (!e->buf) {
115 		e->size = PAGE_ALIGN(len + 1);
116 		e->buf = kmalloc(e->size, GFP_KERNEL);
117 	}
118 	if (!e->buf) {
119 		e->err = -ENOMEM;
120 		return false;
121 	}
122 
123 	return true;
124 }
125 
126 __printf(2, 0)
127 static void i915_error_vprintf(struct drm_i915_error_state_buf *e,
128 			       const char *fmt, va_list args)
129 {
130 	va_list ap;
131 	int len;
132 
133 	if (e->err)
134 		return;
135 
136 	va_copy(ap, args);
137 	len = vsnprintf(NULL, 0, fmt, ap);
138 	va_end(ap);
139 	if (len <= 0) {
140 		e->err = len;
141 		return;
142 	}
143 
144 	if (!__i915_error_grow(e, len))
145 		return;
146 
147 	GEM_BUG_ON(e->bytes >= e->size);
148 	len = vscnprintf(e->buf + e->bytes, e->size - e->bytes, fmt, args);
149 	if (len < 0) {
150 		e->err = len;
151 		return;
152 	}
153 	e->bytes += len;
154 }
155 
156 static void i915_error_puts(struct drm_i915_error_state_buf *e, const char *str)
157 {
158 	unsigned len;
159 
160 	if (e->err || !str)
161 		return;
162 
163 	len = strlen(str);
164 	if (!__i915_error_grow(e, len))
165 		return;
166 
167 	GEM_BUG_ON(e->bytes + len > e->size);
168 	memcpy(e->buf + e->bytes, str, len);
169 	e->bytes += len;
170 }
171 
172 #define err_printf(e, ...) i915_error_printf(e, __VA_ARGS__)
173 #define err_puts(e, s) i915_error_puts(e, s)
174 
175 static void __i915_printfn_error(struct drm_printer *p, struct va_format *vaf)
176 {
177 	i915_error_vprintf(p->arg, vaf->fmt, *vaf->va);
178 }
179 
180 static inline struct drm_printer
181 i915_error_printer(struct drm_i915_error_state_buf *e)
182 {
183 	struct drm_printer p = {
184 		.printfn = __i915_printfn_error,
185 		.arg = e,
186 	};
187 	return p;
188 }
189 
190 /* single threaded page allocator with a reserved stash for emergencies */
191 static void pool_fini(struct folio_batch *fbatch)
192 {
193 	folio_batch_release(fbatch);
194 }
195 
196 static int pool_refill(struct folio_batch *fbatch, gfp_t gfp)
197 {
198 	while (folio_batch_space(fbatch)) {
199 		struct folio *folio;
200 
201 		folio = folio_alloc(gfp, 0);
202 		if (!folio)
203 			return -ENOMEM;
204 
205 		folio_batch_add(fbatch, folio);
206 	}
207 
208 	return 0;
209 }
210 
211 static int pool_init(struct folio_batch *fbatch, gfp_t gfp)
212 {
213 	int err;
214 
215 	folio_batch_init(fbatch);
216 
217 	err = pool_refill(fbatch, gfp);
218 	if (err)
219 		pool_fini(fbatch);
220 
221 	return err;
222 }
223 
224 static void *pool_alloc(struct folio_batch *fbatch, gfp_t gfp)
225 {
226 	struct folio *folio;
227 
228 	folio = folio_alloc(gfp, 0);
229 	if (!folio && folio_batch_count(fbatch))
230 		folio = fbatch->folios[--fbatch->nr];
231 
232 	return folio ? folio_address(folio) : NULL;
233 }
234 
235 static void pool_free(struct folio_batch *fbatch, void *addr)
236 {
237 	struct folio *folio = virt_to_folio(addr);
238 
239 	if (folio_batch_space(fbatch))
240 		folio_batch_add(fbatch, folio);
241 	else
242 		folio_put(folio);
243 }
244 
245 #ifdef CONFIG_DRM_I915_COMPRESS_ERROR
246 
247 struct i915_vma_compress {
248 	struct folio_batch pool;
249 	struct z_stream_s zstream;
250 	void *tmp;
251 };
252 
253 static bool compress_init(struct i915_vma_compress *c)
254 {
255 	struct z_stream_s *zstream = &c->zstream;
256 
257 	if (pool_init(&c->pool, ALLOW_FAIL))
258 		return false;
259 
260 	zstream->workspace =
261 		kmalloc(zlib_deflate_workspacesize(MAX_WBITS, MAX_MEM_LEVEL),
262 			ALLOW_FAIL);
263 	if (!zstream->workspace) {
264 		pool_fini(&c->pool);
265 		return false;
266 	}
267 
268 	c->tmp = NULL;
269 	if (i915_has_memcpy_from_wc())
270 		c->tmp = pool_alloc(&c->pool, ALLOW_FAIL);
271 
272 	return true;
273 }
274 
275 static bool compress_start(struct i915_vma_compress *c)
276 {
277 	struct z_stream_s *zstream = &c->zstream;
278 	void *workspace = zstream->workspace;
279 
280 	memset(zstream, 0, sizeof(*zstream));
281 	zstream->workspace = workspace;
282 
283 	return zlib_deflateInit(zstream, Z_DEFAULT_COMPRESSION) == Z_OK;
284 }
285 
286 static void *compress_next_page(struct i915_vma_compress *c,
287 				struct i915_vma_coredump *dst)
288 {
289 	void *page_addr;
290 	struct page *page;
291 
292 	page_addr = pool_alloc(&c->pool, ALLOW_FAIL);
293 	if (!page_addr)
294 		return ERR_PTR(-ENOMEM);
295 
296 	page = virt_to_page(page_addr);
297 	list_add_tail(&page->lru, &dst->page_list);
298 	return page_addr;
299 }
300 
301 static int compress_page(struct i915_vma_compress *c,
302 			 void *src,
303 			 struct i915_vma_coredump *dst,
304 			 bool wc)
305 {
306 	struct z_stream_s *zstream = &c->zstream;
307 
308 	zstream->next_in = src;
309 	if (wc && c->tmp && i915_memcpy_from_wc(c->tmp, src, PAGE_SIZE))
310 		zstream->next_in = c->tmp;
311 	zstream->avail_in = PAGE_SIZE;
312 
313 	do {
314 		if (zstream->avail_out == 0) {
315 			zstream->next_out = compress_next_page(c, dst);
316 			if (IS_ERR(zstream->next_out))
317 				return PTR_ERR(zstream->next_out);
318 
319 			zstream->avail_out = PAGE_SIZE;
320 		}
321 
322 		if (zlib_deflate(zstream, Z_NO_FLUSH) != Z_OK)
323 			return -EIO;
324 
325 		cond_resched();
326 	} while (zstream->avail_in);
327 
328 	/* Fallback to uncompressed if we increase size? */
329 	if (0 && zstream->total_out > zstream->total_in)
330 		return -E2BIG;
331 
332 	return 0;
333 }
334 
335 static int compress_flush(struct i915_vma_compress *c,
336 			  struct i915_vma_coredump *dst)
337 {
338 	struct z_stream_s *zstream = &c->zstream;
339 
340 	do {
341 		switch (zlib_deflate(zstream, Z_FINISH)) {
342 		case Z_OK: /* more space requested */
343 			zstream->next_out = compress_next_page(c, dst);
344 			if (IS_ERR(zstream->next_out))
345 				return PTR_ERR(zstream->next_out);
346 
347 			zstream->avail_out = PAGE_SIZE;
348 			break;
349 
350 		case Z_STREAM_END:
351 			goto end;
352 
353 		default: /* any error */
354 			return -EIO;
355 		}
356 	} while (1);
357 
358 end:
359 	memset(zstream->next_out, 0, zstream->avail_out);
360 	dst->unused = zstream->avail_out;
361 	return 0;
362 }
363 
364 static void compress_finish(struct i915_vma_compress *c)
365 {
366 	zlib_deflateEnd(&c->zstream);
367 }
368 
369 static void compress_fini(struct i915_vma_compress *c)
370 {
371 	kfree(c->zstream.workspace);
372 	if (c->tmp)
373 		pool_free(&c->pool, c->tmp);
374 	pool_fini(&c->pool);
375 }
376 
377 static void err_compression_marker(struct drm_i915_error_state_buf *m)
378 {
379 	err_puts(m, ":");
380 }
381 
382 #else
383 
384 struct i915_vma_compress {
385 	struct folio_batch pool;
386 };
387 
388 static bool compress_init(struct i915_vma_compress *c)
389 {
390 	return pool_init(&c->pool, ALLOW_FAIL) == 0;
391 }
392 
393 static bool compress_start(struct i915_vma_compress *c)
394 {
395 	return true;
396 }
397 
398 static int compress_page(struct i915_vma_compress *c,
399 			 void *src,
400 			 struct i915_vma_coredump *dst,
401 			 bool wc)
402 {
403 	void *ptr;
404 
405 	ptr = pool_alloc(&c->pool, ALLOW_FAIL);
406 	if (!ptr)
407 		return -ENOMEM;
408 
409 	if (!(wc && i915_memcpy_from_wc(ptr, src, PAGE_SIZE)))
410 		memcpy(ptr, src, PAGE_SIZE);
411 	list_add_tail(&virt_to_page(ptr)->lru, &dst->page_list);
412 	cond_resched();
413 
414 	return 0;
415 }
416 
417 static int compress_flush(struct i915_vma_compress *c,
418 			  struct i915_vma_coredump *dst)
419 {
420 	return 0;
421 }
422 
423 static void compress_finish(struct i915_vma_compress *c)
424 {
425 }
426 
427 static void compress_fini(struct i915_vma_compress *c)
428 {
429 	pool_fini(&c->pool);
430 }
431 
432 static void err_compression_marker(struct drm_i915_error_state_buf *m)
433 {
434 	err_puts(m, "~");
435 }
436 
437 #endif
438 
439 static void error_print_instdone(struct drm_i915_error_state_buf *m,
440 				 const struct intel_engine_coredump *ee)
441 {
442 	int slice;
443 	int subslice;
444 	int iter;
445 
446 	err_printf(m, "  INSTDONE: 0x%08x\n",
447 		   ee->instdone.instdone);
448 
449 	if (ee->engine->class != RENDER_CLASS || GRAPHICS_VER(m->i915) <= 3)
450 		return;
451 
452 	err_printf(m, "  SC_INSTDONE: 0x%08x\n",
453 		   ee->instdone.slice_common);
454 
455 	if (GRAPHICS_VER(m->i915) <= 6)
456 		return;
457 
458 	for_each_ss_steering(iter, ee->engine->gt, slice, subslice)
459 		err_printf(m, "  SAMPLER_INSTDONE[%d][%d]: 0x%08x\n",
460 			   slice, subslice,
461 			   ee->instdone.sampler[slice][subslice]);
462 
463 	for_each_ss_steering(iter, ee->engine->gt, slice, subslice)
464 		err_printf(m, "  ROW_INSTDONE[%d][%d]: 0x%08x\n",
465 			   slice, subslice,
466 			   ee->instdone.row[slice][subslice]);
467 
468 	if (GRAPHICS_VER(m->i915) < 12)
469 		return;
470 
471 	if (GRAPHICS_VER_FULL(m->i915) >= IP_VER(12, 55)) {
472 		for_each_ss_steering(iter, ee->engine->gt, slice, subslice)
473 			err_printf(m, "  GEOM_SVGUNIT_INSTDONE[%d][%d]: 0x%08x\n",
474 				   slice, subslice,
475 				   ee->instdone.geom_svg[slice][subslice]);
476 	}
477 
478 	err_printf(m, "  SC_INSTDONE_EXTRA: 0x%08x\n",
479 		   ee->instdone.slice_common_extra[0]);
480 	err_printf(m, "  SC_INSTDONE_EXTRA2: 0x%08x\n",
481 		   ee->instdone.slice_common_extra[1]);
482 }
483 
484 static void error_print_request(struct drm_i915_error_state_buf *m,
485 				const char *prefix,
486 				const struct i915_request_coredump *erq)
487 {
488 	if (!erq->seqno)
489 		return;
490 
491 	err_printf(m, "%s pid %d, seqno %8x:%08x%s%s, prio %d, head %08x, tail %08x\n",
492 		   prefix, erq->pid, erq->context, erq->seqno,
493 		   test_bit(DMA_FENCE_FLAG_SIGNALED_BIT,
494 			    &erq->flags) ? "!" : "",
495 		   test_bit(DMA_FENCE_FLAG_ENABLE_SIGNAL_BIT,
496 			    &erq->flags) ? "+" : "",
497 		   erq->sched_attr.priority,
498 		   erq->head, erq->tail);
499 }
500 
501 static void error_print_context(struct drm_i915_error_state_buf *m,
502 				const char *header,
503 				const struct i915_gem_context_coredump *ctx)
504 {
505 	err_printf(m, "%s%s[%d] prio %d, guilty %d active %d, runtime total %lluns, avg %lluns\n",
506 		   header, ctx->comm, ctx->pid, ctx->sched_attr.priority,
507 		   ctx->guilty, ctx->active,
508 		   ctx->total_runtime, ctx->avg_runtime);
509 	err_printf(m, "  context timeline seqno %u\n", ctx->hwsp_seqno);
510 }
511 
512 static struct i915_vma_coredump *
513 __find_vma(struct i915_vma_coredump *vma, const char *name)
514 {
515 	while (vma) {
516 		if (strcmp(vma->name, name) == 0)
517 			return vma;
518 		vma = vma->next;
519 	}
520 
521 	return NULL;
522 }
523 
524 static struct i915_vma_coredump *
525 intel_gpu_error_find_batch(const struct intel_engine_coredump *ee)
526 {
527 	return __find_vma(ee->vma, "batch");
528 }
529 
530 static void error_print_engine(struct drm_i915_error_state_buf *m,
531 			       const struct intel_engine_coredump *ee)
532 {
533 	struct i915_vma_coredump *batch;
534 	int n;
535 
536 	err_printf(m, "%s command stream:\n", ee->engine->name);
537 	err_printf(m, "  CCID:  0x%08x\n", ee->ccid);
538 	err_printf(m, "  START: 0x%08x\n", ee->start);
539 	err_printf(m, "  HEAD:  0x%08x [0x%08x]\n", ee->head, ee->rq_head);
540 	err_printf(m, "  TAIL:  0x%08x [0x%08x, 0x%08x]\n",
541 		   ee->tail, ee->rq_post, ee->rq_tail);
542 	err_printf(m, "  CTL:   0x%08x\n", ee->ctl);
543 	err_printf(m, "  MODE:  0x%08x\n", ee->mode);
544 	err_printf(m, "  HWS:   0x%08x\n", ee->hws);
545 	err_printf(m, "  ACTHD: 0x%08x %08x\n",
546 		   (u32)(ee->acthd>>32), (u32)ee->acthd);
547 	err_printf(m, "  IPEIR: 0x%08x\n", ee->ipeir);
548 	err_printf(m, "  IPEHR: 0x%08x\n", ee->ipehr);
549 	err_printf(m, "  ESR:   0x%08x\n", ee->esr);
550 
551 	error_print_instdone(m, ee);
552 
553 	batch = intel_gpu_error_find_batch(ee);
554 	if (batch) {
555 		u64 start = batch->gtt_offset;
556 		u64 end = start + batch->gtt_size;
557 
558 		err_printf(m, "  batch: [0x%08x_%08x, 0x%08x_%08x]\n",
559 			   upper_32_bits(start), lower_32_bits(start),
560 			   upper_32_bits(end), lower_32_bits(end));
561 	}
562 	if (GRAPHICS_VER(m->i915) >= 4) {
563 		err_printf(m, "  BBADDR: 0x%08x_%08x\n",
564 			   (u32)(ee->bbaddr>>32), (u32)ee->bbaddr);
565 		err_printf(m, "  BB_STATE: 0x%08x\n", ee->bbstate);
566 		err_printf(m, "  INSTPS: 0x%08x\n", ee->instps);
567 	}
568 	err_printf(m, "  INSTPM: 0x%08x\n", ee->instpm);
569 	err_printf(m, "  FADDR: 0x%08x %08x\n", upper_32_bits(ee->faddr),
570 		   lower_32_bits(ee->faddr));
571 	if (GRAPHICS_VER(m->i915) >= 6) {
572 		err_printf(m, "  RC PSMI: 0x%08x\n", ee->rc_psmi);
573 		err_printf(m, "  FAULT_REG: 0x%08x\n", ee->fault_reg);
574 	}
575 	if (GRAPHICS_VER(m->i915) >= 11) {
576 		err_printf(m, "  NOPID: 0x%08x\n", ee->nopid);
577 		err_printf(m, "  EXCC: 0x%08x\n", ee->excc);
578 		err_printf(m, "  CMD_CCTL: 0x%08x\n", ee->cmd_cctl);
579 		err_printf(m, "  CSCMDOP: 0x%08x\n", ee->cscmdop);
580 		err_printf(m, "  CTX_SR_CTL: 0x%08x\n", ee->ctx_sr_ctl);
581 		err_printf(m, "  DMA_FADDR_HI: 0x%08x\n", ee->dma_faddr_hi);
582 		err_printf(m, "  DMA_FADDR_LO: 0x%08x\n", ee->dma_faddr_lo);
583 	}
584 	if (HAS_PPGTT(m->i915)) {
585 		err_printf(m, "  GFX_MODE: 0x%08x\n", ee->vm_info.gfx_mode);
586 
587 		if (GRAPHICS_VER(m->i915) >= 8) {
588 			int i;
589 			for (i = 0; i < 4; i++)
590 				err_printf(m, "  PDP%d: 0x%016llx\n",
591 					   i, ee->vm_info.pdp[i]);
592 		} else {
593 			err_printf(m, "  PP_DIR_BASE: 0x%08x\n",
594 				   ee->vm_info.pp_dir_base);
595 		}
596 	}
597 
598 	for (n = 0; n < ee->num_ports; n++) {
599 		err_printf(m, "  ELSP[%d]:", n);
600 		error_print_request(m, " ", &ee->execlist[n]);
601 	}
602 }
603 
604 void i915_error_printf(struct drm_i915_error_state_buf *e, const char *f, ...)
605 {
606 	va_list args;
607 
608 	va_start(args, f);
609 	i915_error_vprintf(e, f, args);
610 	va_end(args);
611 }
612 
613 static void intel_gpu_error_print_vma(struct drm_i915_error_state_buf *m,
614 				      const struct intel_engine_cs *engine,
615 				      const struct i915_vma_coredump *vma)
616 {
617 	char out[ASCII85_BUFSZ];
618 	struct page *page;
619 
620 	if (!vma)
621 		return;
622 
623 	err_printf(m, "%s --- %s = 0x%08x %08x\n",
624 		   engine ? engine->name : "global", vma->name,
625 		   upper_32_bits(vma->gtt_offset),
626 		   lower_32_bits(vma->gtt_offset));
627 
628 	if (vma->gtt_page_sizes > I915_GTT_PAGE_SIZE_4K)
629 		err_printf(m, "gtt_page_sizes = 0x%08x\n", vma->gtt_page_sizes);
630 
631 	err_compression_marker(m);
632 	list_for_each_entry(page, &vma->page_list, lru) {
633 		int i, len;
634 		const u32 *addr = page_address(page);
635 
636 		len = PAGE_SIZE;
637 		if (page == list_last_entry(&vma->page_list, typeof(*page), lru))
638 			len -= vma->unused;
639 		len = ascii85_encode_len(len);
640 
641 		for (i = 0; i < len; i++)
642 			err_puts(m, ascii85_encode(addr[i], out));
643 	}
644 	err_puts(m, "\n");
645 }
646 
647 static void err_print_capabilities(struct drm_i915_error_state_buf *m,
648 				   struct i915_gpu_coredump *error)
649 {
650 	struct drm_printer p = i915_error_printer(m);
651 
652 	intel_device_info_print(&error->device_info, &error->runtime_info, &p);
653 	intel_display_device_info_print(&error->display_device_info,
654 					&error->display_runtime_info, &p);
655 	intel_driver_caps_print(&error->driver_caps, &p);
656 }
657 
658 static void err_print_params(struct drm_i915_error_state_buf *m,
659 			     const struct i915_params *params)
660 {
661 	struct drm_printer p = i915_error_printer(m);
662 
663 	i915_params_dump(params, &p);
664 	intel_display_params_dump(m->i915, &p);
665 }
666 
667 static void err_print_pciid(struct drm_i915_error_state_buf *m,
668 			    struct drm_i915_private *i915)
669 {
670 	struct pci_dev *pdev = to_pci_dev(i915->drm.dev);
671 
672 	err_printf(m, "PCI ID: 0x%04x\n", pdev->device);
673 	err_printf(m, "PCI Revision: 0x%02x\n", pdev->revision);
674 	err_printf(m, "PCI Subsystem: %04x:%04x\n",
675 		   pdev->subsystem_vendor,
676 		   pdev->subsystem_device);
677 }
678 
679 static void err_print_guc_ctb(struct drm_i915_error_state_buf *m,
680 			      const char *name,
681 			      const struct intel_ctb_coredump *ctb)
682 {
683 	if (!ctb->size)
684 		return;
685 
686 	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",
687 		   name, ctb->raw_status, ctb->raw_head, ctb->raw_tail,
688 		   ctb->head, ctb->tail, ctb->desc_offset, ctb->cmds_offset, ctb->size);
689 }
690 
691 static void err_print_uc(struct drm_i915_error_state_buf *m,
692 			 const struct intel_uc_coredump *error_uc)
693 {
694 	struct drm_printer p = i915_error_printer(m);
695 
696 	intel_uc_fw_dump(&error_uc->guc_fw, &p);
697 	intel_uc_fw_dump(&error_uc->huc_fw, &p);
698 	err_printf(m, "GuC timestamp: 0x%08x\n", error_uc->guc.timestamp);
699 	intel_gpu_error_print_vma(m, NULL, error_uc->guc.vma_log);
700 	err_printf(m, "GuC CTB fence: %d\n", error_uc->guc.last_fence);
701 	err_print_guc_ctb(m, "Send", error_uc->guc.ctb + 0);
702 	err_print_guc_ctb(m, "Recv", error_uc->guc.ctb + 1);
703 	intel_gpu_error_print_vma(m, NULL, error_uc->guc.vma_ctb);
704 }
705 
706 static void err_free_sgl(struct scatterlist *sgl)
707 {
708 	while (sgl) {
709 		struct scatterlist *sg;
710 
711 		for (sg = sgl; !sg_is_chain(sg); sg++) {
712 			kfree(sg_virt(sg));
713 			if (sg_is_last(sg))
714 				break;
715 		}
716 
717 		sg = sg_is_last(sg) ? NULL : sg_chain_ptr(sg);
718 		free_page((unsigned long)sgl);
719 		sgl = sg;
720 	}
721 }
722 
723 static void err_print_gt_info(struct drm_i915_error_state_buf *m,
724 			      struct intel_gt_coredump *gt)
725 {
726 	struct drm_printer p = i915_error_printer(m);
727 
728 	intel_gt_info_print(&gt->info, &p);
729 	intel_sseu_print_topology(gt->_gt->i915, &gt->info.sseu, &p);
730 }
731 
732 static void err_print_gt_display(struct drm_i915_error_state_buf *m,
733 				 struct intel_gt_coredump *gt)
734 {
735 	err_printf(m, "IER: 0x%08x\n", gt->ier);
736 	err_printf(m, "DERRMR: 0x%08x\n", gt->derrmr);
737 }
738 
739 static void err_print_gt_global_nonguc(struct drm_i915_error_state_buf *m,
740 				       struct intel_gt_coredump *gt)
741 {
742 	int i;
743 
744 	err_printf(m, "GT awake: %s\n", str_yes_no(gt->awake));
745 	err_printf(m, "CS timestamp frequency: %u Hz, %d ns\n",
746 		   gt->clock_frequency, gt->clock_period_ns);
747 	err_printf(m, "EIR: 0x%08x\n", gt->eir);
748 	err_printf(m, "PGTBL_ER: 0x%08x\n", gt->pgtbl_er);
749 
750 	for (i = 0; i < gt->ngtier; i++)
751 		err_printf(m, "GTIER[%d]: 0x%08x\n", i, gt->gtier[i]);
752 }
753 
754 static void err_print_gt_global(struct drm_i915_error_state_buf *m,
755 				struct intel_gt_coredump *gt)
756 {
757 	err_printf(m, "FORCEWAKE: 0x%08x\n", gt->forcewake);
758 
759 	if (IS_GRAPHICS_VER(m->i915, 6, 11)) {
760 		err_printf(m, "ERROR: 0x%08x\n", gt->error);
761 		err_printf(m, "DONE_REG: 0x%08x\n", gt->done_reg);
762 	}
763 
764 	if (GRAPHICS_VER(m->i915) >= 8)
765 		err_printf(m, "FAULT_TLB_DATA: 0x%08x 0x%08x\n",
766 			   gt->fault_data1, gt->fault_data0);
767 
768 	if (GRAPHICS_VER(m->i915) == 7)
769 		err_printf(m, "ERR_INT: 0x%08x\n", gt->err_int);
770 
771 	if (IS_GRAPHICS_VER(m->i915, 8, 11))
772 		err_printf(m, "GTT_CACHE_EN: 0x%08x\n", gt->gtt_cache);
773 
774 	if (GRAPHICS_VER(m->i915) == 12)
775 		err_printf(m, "AUX_ERR_DBG: 0x%08x\n", gt->aux_err);
776 
777 	if (GRAPHICS_VER(m->i915) >= 12) {
778 		int i;
779 
780 		for (i = 0; i < I915_MAX_SFC; i++) {
781 			/*
782 			 * SFC_DONE resides in the VD forcewake domain, so it
783 			 * only exists if the corresponding VCS engine is
784 			 * present.
785 			 */
786 			if ((gt->_gt->info.sfc_mask & BIT(i)) == 0 ||
787 			    !HAS_ENGINE(gt->_gt, _VCS(i * 2)))
788 				continue;
789 
790 			err_printf(m, "  SFC_DONE[%d]: 0x%08x\n", i,
791 				   gt->sfc_done[i]);
792 		}
793 
794 		err_printf(m, "  GAM_DONE: 0x%08x\n", gt->gam_done);
795 	}
796 }
797 
798 static void err_print_gt_fences(struct drm_i915_error_state_buf *m,
799 				struct intel_gt_coredump *gt)
800 {
801 	int i;
802 
803 	for (i = 0; i < gt->nfence; i++)
804 		err_printf(m, "  fence[%d] = %08llx\n", i, gt->fence[i]);
805 }
806 
807 static void err_print_gt_engines(struct drm_i915_error_state_buf *m,
808 				 struct intel_gt_coredump *gt)
809 {
810 	const struct intel_engine_coredump *ee;
811 
812 	for (ee = gt->engine; ee; ee = ee->next) {
813 		const struct i915_vma_coredump *vma;
814 
815 		if (gt->uc && gt->uc->guc.is_guc_capture) {
816 			if (ee->guc_capture_node)
817 				intel_guc_capture_print_engine_node(m, ee);
818 			else
819 				err_printf(m, "  Missing GuC capture node for %s\n",
820 					   ee->engine->name);
821 		} else {
822 			error_print_engine(m, ee);
823 		}
824 
825 		err_printf(m, "  hung: %u\n", ee->hung);
826 		err_printf(m, "  engine reset count: %u\n", ee->reset_count);
827 		error_print_context(m, "  Active context: ", &ee->context);
828 
829 		for (vma = ee->vma; vma; vma = vma->next)
830 			intel_gpu_error_print_vma(m, ee->engine, vma);
831 	}
832 
833 }
834 
835 static void __err_print_to_sgl(struct drm_i915_error_state_buf *m,
836 			       struct i915_gpu_coredump *error)
837 {
838 	const struct intel_engine_coredump *ee;
839 	struct timespec64 ts;
840 
841 	if (*error->error_msg)
842 		err_printf(m, "%s\n", error->error_msg);
843 	err_printf(m, "Kernel: %s %s\n",
844 		   init_utsname()->release,
845 		   init_utsname()->machine);
846 	err_printf(m, "Driver: %s\n", DRIVER_DATE);
847 	ts = ktime_to_timespec64(error->time);
848 	err_printf(m, "Time: %lld s %ld us\n",
849 		   (s64)ts.tv_sec, ts.tv_nsec / NSEC_PER_USEC);
850 	ts = ktime_to_timespec64(error->boottime);
851 	err_printf(m, "Boottime: %lld s %ld us\n",
852 		   (s64)ts.tv_sec, ts.tv_nsec / NSEC_PER_USEC);
853 	ts = ktime_to_timespec64(error->uptime);
854 	err_printf(m, "Uptime: %lld s %ld us\n",
855 		   (s64)ts.tv_sec, ts.tv_nsec / NSEC_PER_USEC);
856 	err_printf(m, "Capture: %lu jiffies; %d ms ago\n",
857 		   error->capture, jiffies_to_msecs(jiffies - error->capture));
858 
859 	for (ee = error->gt ? error->gt->engine : NULL; ee; ee = ee->next)
860 		err_printf(m, "Active process (on ring %s): %s [%d]\n",
861 			   ee->engine->name,
862 			   ee->context.comm,
863 			   ee->context.pid);
864 
865 	err_printf(m, "Reset count: %u\n", error->reset_count);
866 	err_printf(m, "Suspend count: %u\n", error->suspend_count);
867 	err_printf(m, "Platform: %s\n", intel_platform_name(error->device_info.platform));
868 	err_printf(m, "Subplatform: 0x%x\n",
869 		   intel_subplatform(&error->runtime_info,
870 				     error->device_info.platform));
871 	err_print_pciid(m, m->i915);
872 
873 	err_printf(m, "IOMMU enabled?: %d\n", error->iommu);
874 
875 	intel_dmc_print_error_state(m, m->i915);
876 
877 	err_printf(m, "RPM wakelock: %s\n", str_yes_no(error->wakelock));
878 	err_printf(m, "PM suspended: %s\n", str_yes_no(error->suspended));
879 
880 	if (error->gt) {
881 		bool print_guc_capture = false;
882 
883 		if (error->gt->uc && error->gt->uc->guc.is_guc_capture)
884 			print_guc_capture = true;
885 
886 		err_print_gt_display(m, error->gt);
887 		err_print_gt_global_nonguc(m, error->gt);
888 		err_print_gt_fences(m, error->gt);
889 
890 		/*
891 		 * GuC dumped global, eng-class and eng-instance registers together
892 		 * as part of engine state dump so we print in err_print_gt_engines
893 		 */
894 		if (!print_guc_capture)
895 			err_print_gt_global(m, error->gt);
896 
897 		err_print_gt_engines(m, error->gt);
898 
899 		if (error->gt->uc)
900 			err_print_uc(m, error->gt->uc);
901 
902 		err_print_gt_info(m, error->gt);
903 	}
904 
905 	if (error->overlay)
906 		intel_overlay_print_error_state(m, error->overlay);
907 
908 	err_print_capabilities(m, error);
909 	err_print_params(m, &error->params);
910 }
911 
912 static int err_print_to_sgl(struct i915_gpu_coredump *error)
913 {
914 	struct drm_i915_error_state_buf m;
915 
916 	if (IS_ERR(error))
917 		return PTR_ERR(error);
918 
919 	if (READ_ONCE(error->sgl))
920 		return 0;
921 
922 	memset(&m, 0, sizeof(m));
923 	m.i915 = error->i915;
924 
925 	__err_print_to_sgl(&m, error);
926 
927 	if (m.buf) {
928 		__sg_set_buf(m.cur++, m.buf, m.bytes, m.iter);
929 		m.bytes = 0;
930 		m.buf = NULL;
931 	}
932 	if (m.cur) {
933 		GEM_BUG_ON(m.end < m.cur);
934 		sg_mark_end(m.cur - 1);
935 	}
936 	GEM_BUG_ON(m.sgl && !m.cur);
937 
938 	if (m.err) {
939 		err_free_sgl(m.sgl);
940 		return m.err;
941 	}
942 
943 	if (cmpxchg(&error->sgl, NULL, m.sgl))
944 		err_free_sgl(m.sgl);
945 
946 	return 0;
947 }
948 
949 ssize_t i915_gpu_coredump_copy_to_buffer(struct i915_gpu_coredump *error,
950 					 char *buf, loff_t off, size_t rem)
951 {
952 	struct scatterlist *sg;
953 	size_t count;
954 	loff_t pos;
955 	int err;
956 
957 	if (!error || !rem)
958 		return 0;
959 
960 	err = err_print_to_sgl(error);
961 	if (err)
962 		return err;
963 
964 	sg = READ_ONCE(error->fit);
965 	if (!sg || off < sg->dma_address)
966 		sg = error->sgl;
967 	if (!sg)
968 		return 0;
969 
970 	pos = sg->dma_address;
971 	count = 0;
972 	do {
973 		size_t len, start;
974 
975 		if (sg_is_chain(sg)) {
976 			sg = sg_chain_ptr(sg);
977 			GEM_BUG_ON(sg_is_chain(sg));
978 		}
979 
980 		len = sg->length;
981 		if (pos + len <= off) {
982 			pos += len;
983 			continue;
984 		}
985 
986 		start = sg->offset;
987 		if (pos < off) {
988 			GEM_BUG_ON(off - pos > len);
989 			len -= off - pos;
990 			start += off - pos;
991 			pos = off;
992 		}
993 
994 		len = min(len, rem);
995 		GEM_BUG_ON(!len || len > sg->length);
996 
997 		memcpy(buf, page_address(sg_page(sg)) + start, len);
998 
999 		count += len;
1000 		pos += len;
1001 
1002 		buf += len;
1003 		rem -= len;
1004 		if (!rem) {
1005 			WRITE_ONCE(error->fit, sg);
1006 			break;
1007 		}
1008 	} while (!sg_is_last(sg++));
1009 
1010 	return count;
1011 }
1012 
1013 static void i915_vma_coredump_free(struct i915_vma_coredump *vma)
1014 {
1015 	while (vma) {
1016 		struct i915_vma_coredump *next = vma->next;
1017 		struct page *page, *n;
1018 
1019 		list_for_each_entry_safe(page, n, &vma->page_list, lru) {
1020 			list_del_init(&page->lru);
1021 			__free_page(page);
1022 		}
1023 
1024 		kfree(vma);
1025 		vma = next;
1026 	}
1027 }
1028 
1029 static void cleanup_params(struct i915_gpu_coredump *error)
1030 {
1031 	i915_params_free(&error->params);
1032 	intel_display_params_free(&error->display_params);
1033 }
1034 
1035 static void cleanup_uc(struct intel_uc_coredump *uc)
1036 {
1037 	kfree(uc->guc_fw.file_selected.path);
1038 	kfree(uc->huc_fw.file_selected.path);
1039 	kfree(uc->guc_fw.file_wanted.path);
1040 	kfree(uc->huc_fw.file_wanted.path);
1041 	i915_vma_coredump_free(uc->guc.vma_log);
1042 	i915_vma_coredump_free(uc->guc.vma_ctb);
1043 
1044 	kfree(uc);
1045 }
1046 
1047 static void cleanup_gt(struct intel_gt_coredump *gt)
1048 {
1049 	while (gt->engine) {
1050 		struct intel_engine_coredump *ee = gt->engine;
1051 
1052 		gt->engine = ee->next;
1053 
1054 		i915_vma_coredump_free(ee->vma);
1055 		intel_guc_capture_free_node(ee);
1056 		kfree(ee);
1057 	}
1058 
1059 	if (gt->uc)
1060 		cleanup_uc(gt->uc);
1061 
1062 	kfree(gt);
1063 }
1064 
1065 void __i915_gpu_coredump_free(struct kref *error_ref)
1066 {
1067 	struct i915_gpu_coredump *error =
1068 		container_of(error_ref, typeof(*error), ref);
1069 
1070 	while (error->gt) {
1071 		struct intel_gt_coredump *gt = error->gt;
1072 
1073 		error->gt = gt->next;
1074 		cleanup_gt(gt);
1075 	}
1076 
1077 	kfree(error->overlay);
1078 
1079 	cleanup_params(error);
1080 
1081 	err_free_sgl(error->sgl);
1082 	kfree(error);
1083 }
1084 
1085 static struct i915_vma_coredump *
1086 i915_vma_coredump_create(const struct intel_gt *gt,
1087 			 const struct i915_vma_resource *vma_res,
1088 			 struct i915_vma_compress *compress,
1089 			 const char *name)
1090 
1091 {
1092 	struct i915_ggtt *ggtt = gt->ggtt;
1093 	const u64 slot = ggtt->error_capture.start;
1094 	struct i915_vma_coredump *dst;
1095 	struct sgt_iter iter;
1096 	int ret;
1097 
1098 	might_sleep();
1099 
1100 	if (!vma_res || !vma_res->bi.pages || !compress)
1101 		return NULL;
1102 
1103 	dst = kmalloc(sizeof(*dst), ALLOW_FAIL);
1104 	if (!dst)
1105 		return NULL;
1106 
1107 	if (!compress_start(compress)) {
1108 		kfree(dst);
1109 		return NULL;
1110 	}
1111 
1112 	INIT_LIST_HEAD(&dst->page_list);
1113 	strcpy(dst->name, name);
1114 	dst->next = NULL;
1115 
1116 	dst->gtt_offset = vma_res->start;
1117 	dst->gtt_size = vma_res->node_size;
1118 	dst->gtt_page_sizes = vma_res->page_sizes_gtt;
1119 	dst->unused = 0;
1120 
1121 	ret = -EINVAL;
1122 	if (drm_mm_node_allocated(&ggtt->error_capture)) {
1123 		void __iomem *s;
1124 		dma_addr_t dma;
1125 
1126 		for_each_sgt_daddr(dma, iter, vma_res->bi.pages) {
1127 			mutex_lock(&ggtt->error_mutex);
1128 			if (ggtt->vm.raw_insert_page)
1129 				ggtt->vm.raw_insert_page(&ggtt->vm, dma, slot,
1130 							 i915_gem_get_pat_index(gt->i915,
1131 										I915_CACHE_NONE),
1132 							 0);
1133 			else
1134 				ggtt->vm.insert_page(&ggtt->vm, dma, slot,
1135 						     i915_gem_get_pat_index(gt->i915,
1136 									    I915_CACHE_NONE),
1137 						     0);
1138 			mb();
1139 
1140 			s = io_mapping_map_wc(&ggtt->iomap, slot, PAGE_SIZE);
1141 			ret = compress_page(compress,
1142 					    (void  __force *)s, dst,
1143 					    true);
1144 			io_mapping_unmap(s);
1145 
1146 			mb();
1147 			ggtt->vm.clear_range(&ggtt->vm, slot, PAGE_SIZE);
1148 			mutex_unlock(&ggtt->error_mutex);
1149 			if (ret)
1150 				break;
1151 		}
1152 	} else if (vma_res->bi.lmem) {
1153 		struct intel_memory_region *mem = vma_res->mr;
1154 		dma_addr_t dma;
1155 
1156 		for_each_sgt_daddr(dma, iter, vma_res->bi.pages) {
1157 			dma_addr_t offset = dma - mem->region.start;
1158 			void __iomem *s;
1159 
1160 			if (offset + PAGE_SIZE > resource_size(&mem->io)) {
1161 				ret = -EINVAL;
1162 				break;
1163 			}
1164 
1165 			s = io_mapping_map_wc(&mem->iomap, offset, PAGE_SIZE);
1166 			ret = compress_page(compress,
1167 					    (void __force *)s, dst,
1168 					    true);
1169 			io_mapping_unmap(s);
1170 			if (ret)
1171 				break;
1172 		}
1173 	} else {
1174 		struct page *page;
1175 
1176 		for_each_sgt_page(page, iter, vma_res->bi.pages) {
1177 			void *s;
1178 
1179 			drm_clflush_pages(&page, 1);
1180 
1181 			s = kmap_local_page(page);
1182 			ret = compress_page(compress, s, dst, false);
1183 			kunmap_local(s);
1184 
1185 			drm_clflush_pages(&page, 1);
1186 
1187 			if (ret)
1188 				break;
1189 		}
1190 	}
1191 
1192 	if (ret || compress_flush(compress, dst)) {
1193 		struct page *page, *n;
1194 
1195 		list_for_each_entry_safe_reverse(page, n, &dst->page_list, lru) {
1196 			list_del_init(&page->lru);
1197 			pool_free(&compress->pool, page_address(page));
1198 		}
1199 
1200 		kfree(dst);
1201 		dst = NULL;
1202 	}
1203 	compress_finish(compress);
1204 
1205 	return dst;
1206 }
1207 
1208 static void gt_record_fences(struct intel_gt_coredump *gt)
1209 {
1210 	struct i915_ggtt *ggtt = gt->_gt->ggtt;
1211 	struct intel_uncore *uncore = gt->_gt->uncore;
1212 	int i;
1213 
1214 	if (GRAPHICS_VER(uncore->i915) >= 6) {
1215 		for (i = 0; i < ggtt->num_fences; i++)
1216 			gt->fence[i] =
1217 				intel_uncore_read64(uncore,
1218 						    FENCE_REG_GEN6_LO(i));
1219 	} else if (GRAPHICS_VER(uncore->i915) >= 4) {
1220 		for (i = 0; i < ggtt->num_fences; i++)
1221 			gt->fence[i] =
1222 				intel_uncore_read64(uncore,
1223 						    FENCE_REG_965_LO(i));
1224 	} else {
1225 		for (i = 0; i < ggtt->num_fences; i++)
1226 			gt->fence[i] =
1227 				intel_uncore_read(uncore, FENCE_REG(i));
1228 	}
1229 	gt->nfence = i;
1230 }
1231 
1232 static void engine_record_registers(struct intel_engine_coredump *ee)
1233 {
1234 	const struct intel_engine_cs *engine = ee->engine;
1235 	struct drm_i915_private *i915 = engine->i915;
1236 
1237 	if (GRAPHICS_VER(i915) >= 6) {
1238 		ee->rc_psmi = ENGINE_READ(engine, RING_PSMI_CTL);
1239 
1240 		/*
1241 		 * For the media GT, this ring fault register is not replicated,
1242 		 * so don't do multicast/replicated register read/write
1243 		 * operation on it.
1244 		 */
1245 		if (MEDIA_VER(i915) >= 13 && engine->gt->type == GT_MEDIA)
1246 			ee->fault_reg = intel_uncore_read(engine->uncore,
1247 							  XELPMP_RING_FAULT_REG);
1248 
1249 		else if (GRAPHICS_VER_FULL(i915) >= IP_VER(12, 50))
1250 			ee->fault_reg = intel_gt_mcr_read_any(engine->gt,
1251 							      XEHP_RING_FAULT_REG);
1252 		else if (GRAPHICS_VER(i915) >= 12)
1253 			ee->fault_reg = intel_uncore_read(engine->uncore,
1254 							  GEN12_RING_FAULT_REG);
1255 		else if (GRAPHICS_VER(i915) >= 8)
1256 			ee->fault_reg = intel_uncore_read(engine->uncore,
1257 							  GEN8_RING_FAULT_REG);
1258 		else
1259 			ee->fault_reg = GEN6_RING_FAULT_REG_READ(engine);
1260 	}
1261 
1262 	if (GRAPHICS_VER(i915) >= 4) {
1263 		ee->esr = ENGINE_READ(engine, RING_ESR);
1264 		ee->faddr = ENGINE_READ(engine, RING_DMA_FADD);
1265 		ee->ipeir = ENGINE_READ(engine, RING_IPEIR);
1266 		ee->ipehr = ENGINE_READ(engine, RING_IPEHR);
1267 		ee->instps = ENGINE_READ(engine, RING_INSTPS);
1268 		ee->bbaddr = ENGINE_READ(engine, RING_BBADDR);
1269 		ee->ccid = ENGINE_READ(engine, CCID);
1270 		if (GRAPHICS_VER(i915) >= 8) {
1271 			ee->faddr |= (u64)ENGINE_READ(engine, RING_DMA_FADD_UDW) << 32;
1272 			ee->bbaddr |= (u64)ENGINE_READ(engine, RING_BBADDR_UDW) << 32;
1273 		}
1274 		ee->bbstate = ENGINE_READ(engine, RING_BBSTATE);
1275 	} else {
1276 		ee->faddr = ENGINE_READ(engine, DMA_FADD_I8XX);
1277 		ee->ipeir = ENGINE_READ(engine, IPEIR);
1278 		ee->ipehr = ENGINE_READ(engine, IPEHR);
1279 	}
1280 
1281 	if (GRAPHICS_VER(i915) >= 11) {
1282 		ee->cmd_cctl = ENGINE_READ(engine, RING_CMD_CCTL);
1283 		ee->cscmdop = ENGINE_READ(engine, RING_CSCMDOP);
1284 		ee->ctx_sr_ctl = ENGINE_READ(engine, RING_CTX_SR_CTL);
1285 		ee->dma_faddr_hi = ENGINE_READ(engine, RING_DMA_FADD_UDW);
1286 		ee->dma_faddr_lo = ENGINE_READ(engine, RING_DMA_FADD);
1287 		ee->nopid = ENGINE_READ(engine, RING_NOPID);
1288 		ee->excc = ENGINE_READ(engine, RING_EXCC);
1289 	}
1290 
1291 	intel_engine_get_instdone(engine, &ee->instdone);
1292 
1293 	ee->instpm = ENGINE_READ(engine, RING_INSTPM);
1294 	ee->acthd = intel_engine_get_active_head(engine);
1295 	ee->start = ENGINE_READ(engine, RING_START);
1296 	ee->head = ENGINE_READ(engine, RING_HEAD);
1297 	ee->tail = ENGINE_READ(engine, RING_TAIL);
1298 	ee->ctl = ENGINE_READ(engine, RING_CTL);
1299 	if (GRAPHICS_VER(i915) > 2)
1300 		ee->mode = ENGINE_READ(engine, RING_MI_MODE);
1301 
1302 	if (!HWS_NEEDS_PHYSICAL(i915)) {
1303 		i915_reg_t mmio;
1304 
1305 		if (GRAPHICS_VER(i915) == 7) {
1306 			switch (engine->id) {
1307 			default:
1308 				MISSING_CASE(engine->id);
1309 				fallthrough;
1310 			case RCS0:
1311 				mmio = RENDER_HWS_PGA_GEN7;
1312 				break;
1313 			case BCS0:
1314 				mmio = BLT_HWS_PGA_GEN7;
1315 				break;
1316 			case VCS0:
1317 				mmio = BSD_HWS_PGA_GEN7;
1318 				break;
1319 			case VECS0:
1320 				mmio = VEBOX_HWS_PGA_GEN7;
1321 				break;
1322 			}
1323 		} else if (GRAPHICS_VER(engine->i915) == 6) {
1324 			mmio = RING_HWS_PGA_GEN6(engine->mmio_base);
1325 		} else {
1326 			/* XXX: gen8 returns to sanity */
1327 			mmio = RING_HWS_PGA(engine->mmio_base);
1328 		}
1329 
1330 		ee->hws = intel_uncore_read(engine->uncore, mmio);
1331 	}
1332 
1333 	ee->reset_count = i915_reset_engine_count(&i915->gpu_error, engine);
1334 
1335 	if (HAS_PPGTT(i915)) {
1336 		int i;
1337 
1338 		ee->vm_info.gfx_mode = ENGINE_READ(engine, RING_MODE_GEN7);
1339 
1340 		if (GRAPHICS_VER(i915) == 6) {
1341 			ee->vm_info.pp_dir_base =
1342 				ENGINE_READ(engine, RING_PP_DIR_BASE_READ);
1343 		} else if (GRAPHICS_VER(i915) == 7) {
1344 			ee->vm_info.pp_dir_base =
1345 				ENGINE_READ(engine, RING_PP_DIR_BASE);
1346 		} else if (GRAPHICS_VER(i915) >= 8) {
1347 			u32 base = engine->mmio_base;
1348 
1349 			for (i = 0; i < 4; i++) {
1350 				ee->vm_info.pdp[i] =
1351 					intel_uncore_read(engine->uncore,
1352 							  GEN8_RING_PDP_UDW(base, i));
1353 				ee->vm_info.pdp[i] <<= 32;
1354 				ee->vm_info.pdp[i] |=
1355 					intel_uncore_read(engine->uncore,
1356 							  GEN8_RING_PDP_LDW(base, i));
1357 			}
1358 		}
1359 	}
1360 }
1361 
1362 static void record_request(const struct i915_request *request,
1363 			   struct i915_request_coredump *erq)
1364 {
1365 	erq->flags = request->fence.flags;
1366 	erq->context = request->fence.context;
1367 	erq->seqno = request->fence.seqno;
1368 	erq->sched_attr = request->sched.attr;
1369 	erq->head = request->head;
1370 	erq->tail = request->tail;
1371 
1372 	erq->pid = 0;
1373 	rcu_read_lock();
1374 	if (!intel_context_is_closed(request->context)) {
1375 		const struct i915_gem_context *ctx;
1376 
1377 		ctx = rcu_dereference(request->context->gem_context);
1378 		if (ctx)
1379 			erq->pid = pid_nr(ctx->pid);
1380 	}
1381 	rcu_read_unlock();
1382 }
1383 
1384 static void engine_record_execlists(struct intel_engine_coredump *ee)
1385 {
1386 	const struct intel_engine_execlists * const el = &ee->engine->execlists;
1387 	struct i915_request * const *port = el->active;
1388 	unsigned int n = 0;
1389 
1390 	while (*port)
1391 		record_request(*port++, &ee->execlist[n++]);
1392 
1393 	ee->num_ports = n;
1394 }
1395 
1396 static bool record_context(struct i915_gem_context_coredump *e,
1397 			   struct intel_context *ce)
1398 {
1399 	struct i915_gem_context *ctx;
1400 	struct task_struct *task;
1401 	bool simulated;
1402 
1403 	rcu_read_lock();
1404 	ctx = rcu_dereference(ce->gem_context);
1405 	if (ctx && !kref_get_unless_zero(&ctx->ref))
1406 		ctx = NULL;
1407 	rcu_read_unlock();
1408 	if (!ctx)
1409 		return true;
1410 
1411 	rcu_read_lock();
1412 	task = pid_task(ctx->pid, PIDTYPE_PID);
1413 	if (task) {
1414 		strcpy(e->comm, task->comm);
1415 		e->pid = task->pid;
1416 	}
1417 	rcu_read_unlock();
1418 
1419 	e->sched_attr = ctx->sched;
1420 	e->guilty = atomic_read(&ctx->guilty_count);
1421 	e->active = atomic_read(&ctx->active_count);
1422 	e->hwsp_seqno = (ce->timeline && ce->timeline->hwsp_seqno) ?
1423 				*ce->timeline->hwsp_seqno : ~0U;
1424 
1425 	e->total_runtime = intel_context_get_total_runtime_ns(ce);
1426 	e->avg_runtime = intel_context_get_avg_runtime_ns(ce);
1427 
1428 	simulated = i915_gem_context_no_error_capture(ctx);
1429 
1430 	i915_gem_context_put(ctx);
1431 	return simulated;
1432 }
1433 
1434 struct intel_engine_capture_vma {
1435 	struct intel_engine_capture_vma *next;
1436 	struct i915_vma_resource *vma_res;
1437 	char name[16];
1438 	bool lockdep_cookie;
1439 };
1440 
1441 static struct intel_engine_capture_vma *
1442 capture_vma_snapshot(struct intel_engine_capture_vma *next,
1443 		     struct i915_vma_resource *vma_res,
1444 		     gfp_t gfp, const char *name)
1445 {
1446 	struct intel_engine_capture_vma *c;
1447 
1448 	if (!vma_res)
1449 		return next;
1450 
1451 	c = kmalloc(sizeof(*c), gfp);
1452 	if (!c)
1453 		return next;
1454 
1455 	if (!i915_vma_resource_hold(vma_res, &c->lockdep_cookie)) {
1456 		kfree(c);
1457 		return next;
1458 	}
1459 
1460 	strcpy(c->name, name);
1461 	c->vma_res = i915_vma_resource_get(vma_res);
1462 
1463 	c->next = next;
1464 	return c;
1465 }
1466 
1467 static struct intel_engine_capture_vma *
1468 capture_vma(struct intel_engine_capture_vma *next,
1469 	    struct i915_vma *vma,
1470 	    const char *name,
1471 	    gfp_t gfp)
1472 {
1473 	if (!vma)
1474 		return next;
1475 
1476 	/*
1477 	 * If the vma isn't pinned, then the vma should be snapshotted
1478 	 * to a struct i915_vma_snapshot at command submission time.
1479 	 * Not here.
1480 	 */
1481 	if (GEM_WARN_ON(!i915_vma_is_pinned(vma)))
1482 		return next;
1483 
1484 	next = capture_vma_snapshot(next, vma->resource, gfp, name);
1485 
1486 	return next;
1487 }
1488 
1489 static struct intel_engine_capture_vma *
1490 capture_user(struct intel_engine_capture_vma *capture,
1491 	     const struct i915_request *rq,
1492 	     gfp_t gfp)
1493 {
1494 	struct i915_capture_list *c;
1495 
1496 	for (c = rq->capture_list; c; c = c->next)
1497 		capture = capture_vma_snapshot(capture, c->vma_res, gfp,
1498 					       "user");
1499 
1500 	return capture;
1501 }
1502 
1503 static void add_vma(struct intel_engine_coredump *ee,
1504 		    struct i915_vma_coredump *vma)
1505 {
1506 	if (vma) {
1507 		vma->next = ee->vma;
1508 		ee->vma = vma;
1509 	}
1510 }
1511 
1512 static struct i915_vma_coredump *
1513 create_vma_coredump(const struct intel_gt *gt, struct i915_vma *vma,
1514 		    const char *name, struct i915_vma_compress *compress)
1515 {
1516 	struct i915_vma_coredump *ret = NULL;
1517 	struct i915_vma_resource *vma_res;
1518 	bool lockdep_cookie;
1519 
1520 	if (!vma)
1521 		return NULL;
1522 
1523 	vma_res = vma->resource;
1524 
1525 	if (i915_vma_resource_hold(vma_res, &lockdep_cookie)) {
1526 		ret = i915_vma_coredump_create(gt, vma_res, compress, name);
1527 		i915_vma_resource_unhold(vma_res, lockdep_cookie);
1528 	}
1529 
1530 	return ret;
1531 }
1532 
1533 static void add_vma_coredump(struct intel_engine_coredump *ee,
1534 			     const struct intel_gt *gt,
1535 			     struct i915_vma *vma,
1536 			     const char *name,
1537 			     struct i915_vma_compress *compress)
1538 {
1539 	add_vma(ee, create_vma_coredump(gt, vma, name, compress));
1540 }
1541 
1542 struct intel_engine_coredump *
1543 intel_engine_coredump_alloc(struct intel_engine_cs *engine, gfp_t gfp, u32 dump_flags)
1544 {
1545 	struct intel_engine_coredump *ee;
1546 
1547 	ee = kzalloc(sizeof(*ee), gfp);
1548 	if (!ee)
1549 		return NULL;
1550 
1551 	ee->engine = engine;
1552 
1553 	if (!(dump_flags & CORE_DUMP_FLAG_IS_GUC_CAPTURE)) {
1554 		engine_record_registers(ee);
1555 		engine_record_execlists(ee);
1556 	}
1557 
1558 	return ee;
1559 }
1560 
1561 static struct intel_engine_capture_vma *
1562 engine_coredump_add_context(struct intel_engine_coredump *ee,
1563 			    struct intel_context *ce,
1564 			    gfp_t gfp)
1565 {
1566 	struct intel_engine_capture_vma *vma = NULL;
1567 
1568 	ee->simulated |= record_context(&ee->context, ce);
1569 	if (ee->simulated)
1570 		return NULL;
1571 
1572 	/*
1573 	 * We need to copy these to an anonymous buffer
1574 	 * as the simplest method to avoid being overwritten
1575 	 * by userspace.
1576 	 */
1577 	vma = capture_vma(vma, ce->ring->vma, "ring", gfp);
1578 	vma = capture_vma(vma, ce->state, "HW context", gfp);
1579 
1580 	return vma;
1581 }
1582 
1583 struct intel_engine_capture_vma *
1584 intel_engine_coredump_add_request(struct intel_engine_coredump *ee,
1585 				  struct i915_request *rq,
1586 				  gfp_t gfp)
1587 {
1588 	struct intel_engine_capture_vma *vma;
1589 
1590 	vma = engine_coredump_add_context(ee, rq->context, gfp);
1591 	if (!vma)
1592 		return NULL;
1593 
1594 	/*
1595 	 * We need to copy these to an anonymous buffer
1596 	 * as the simplest method to avoid being overwritten
1597 	 * by userspace.
1598 	 */
1599 	vma = capture_vma_snapshot(vma, rq->batch_res, gfp, "batch");
1600 	vma = capture_user(vma, rq, gfp);
1601 
1602 	ee->rq_head = rq->head;
1603 	ee->rq_post = rq->postfix;
1604 	ee->rq_tail = rq->tail;
1605 
1606 	return vma;
1607 }
1608 
1609 void
1610 intel_engine_coredump_add_vma(struct intel_engine_coredump *ee,
1611 			      struct intel_engine_capture_vma *capture,
1612 			      struct i915_vma_compress *compress)
1613 {
1614 	const struct intel_engine_cs *engine = ee->engine;
1615 
1616 	while (capture) {
1617 		struct intel_engine_capture_vma *this = capture;
1618 		struct i915_vma_resource *vma_res = this->vma_res;
1619 
1620 		add_vma(ee,
1621 			i915_vma_coredump_create(engine->gt, vma_res,
1622 						 compress, this->name));
1623 
1624 		i915_vma_resource_unhold(vma_res, this->lockdep_cookie);
1625 		i915_vma_resource_put(vma_res);
1626 
1627 		capture = this->next;
1628 		kfree(this);
1629 	}
1630 
1631 	add_vma_coredump(ee, engine->gt, engine->status_page.vma,
1632 			 "HW Status", compress);
1633 
1634 	add_vma_coredump(ee, engine->gt, engine->wa_ctx.vma,
1635 			 "WA context", compress);
1636 }
1637 
1638 static struct intel_engine_coredump *
1639 capture_engine(struct intel_engine_cs *engine,
1640 	       struct i915_vma_compress *compress,
1641 	       u32 dump_flags)
1642 {
1643 	struct intel_engine_capture_vma *capture = NULL;
1644 	struct intel_engine_coredump *ee;
1645 	struct intel_context *ce = NULL;
1646 	struct i915_request *rq = NULL;
1647 
1648 	ee = intel_engine_coredump_alloc(engine, ALLOW_FAIL, dump_flags);
1649 	if (!ee)
1650 		return NULL;
1651 
1652 	intel_engine_get_hung_entity(engine, &ce, &rq);
1653 	if (rq && !i915_request_started(rq))
1654 		drm_info(&engine->gt->i915->drm, "Got hung context on %s with active request %lld:%lld [0x%04X] not yet started\n",
1655 			 engine->name, rq->fence.context, rq->fence.seqno, ce->guc_id.id);
1656 
1657 	if (rq) {
1658 		capture = intel_engine_coredump_add_request(ee, rq, ATOMIC_MAYFAIL);
1659 		i915_request_put(rq);
1660 	} else if (ce) {
1661 		capture = engine_coredump_add_context(ee, ce, ATOMIC_MAYFAIL);
1662 	}
1663 
1664 	if (capture) {
1665 		intel_engine_coredump_add_vma(ee, capture, compress);
1666 
1667 		if (dump_flags & CORE_DUMP_FLAG_IS_GUC_CAPTURE)
1668 			intel_guc_capture_get_matching_node(engine->gt, ee, ce);
1669 	} else {
1670 		kfree(ee);
1671 		ee = NULL;
1672 	}
1673 
1674 	return ee;
1675 }
1676 
1677 static void
1678 gt_record_engines(struct intel_gt_coredump *gt,
1679 		  intel_engine_mask_t engine_mask,
1680 		  struct i915_vma_compress *compress,
1681 		  u32 dump_flags)
1682 {
1683 	struct intel_engine_cs *engine;
1684 	enum intel_engine_id id;
1685 
1686 	for_each_engine(engine, gt->_gt, id) {
1687 		struct intel_engine_coredump *ee;
1688 
1689 		/* Refill our page pool before entering atomic section */
1690 		pool_refill(&compress->pool, ALLOW_FAIL);
1691 
1692 		ee = capture_engine(engine, compress, dump_flags);
1693 		if (!ee)
1694 			continue;
1695 
1696 		ee->hung = engine->mask & engine_mask;
1697 
1698 		gt->simulated |= ee->simulated;
1699 		if (ee->simulated) {
1700 			if (dump_flags & CORE_DUMP_FLAG_IS_GUC_CAPTURE)
1701 				intel_guc_capture_free_node(ee);
1702 			kfree(ee);
1703 			continue;
1704 		}
1705 
1706 		ee->next = gt->engine;
1707 		gt->engine = ee;
1708 	}
1709 }
1710 
1711 static void gt_record_guc_ctb(struct intel_ctb_coredump *saved,
1712 			      const struct intel_guc_ct_buffer *ctb,
1713 			      const void *blob_ptr, struct intel_guc *guc)
1714 {
1715 	if (!ctb || !ctb->desc)
1716 		return;
1717 
1718 	saved->raw_status = ctb->desc->status;
1719 	saved->raw_head = ctb->desc->head;
1720 	saved->raw_tail = ctb->desc->tail;
1721 	saved->head = ctb->head;
1722 	saved->tail = ctb->tail;
1723 	saved->size = ctb->size;
1724 	saved->desc_offset = ((void *)ctb->desc) - blob_ptr;
1725 	saved->cmds_offset = ((void *)ctb->cmds) - blob_ptr;
1726 }
1727 
1728 static struct intel_uc_coredump *
1729 gt_record_uc(struct intel_gt_coredump *gt,
1730 	     struct i915_vma_compress *compress)
1731 {
1732 	const struct intel_uc *uc = &gt->_gt->uc;
1733 	struct intel_uc_coredump *error_uc;
1734 
1735 	error_uc = kzalloc(sizeof(*error_uc), ALLOW_FAIL);
1736 	if (!error_uc)
1737 		return NULL;
1738 
1739 	memcpy(&error_uc->guc_fw, &uc->guc.fw, sizeof(uc->guc.fw));
1740 	memcpy(&error_uc->huc_fw, &uc->huc.fw, sizeof(uc->huc.fw));
1741 
1742 	error_uc->guc_fw.file_selected.path = kstrdup(uc->guc.fw.file_selected.path, ALLOW_FAIL);
1743 	error_uc->huc_fw.file_selected.path = kstrdup(uc->huc.fw.file_selected.path, ALLOW_FAIL);
1744 	error_uc->guc_fw.file_wanted.path = kstrdup(uc->guc.fw.file_wanted.path, ALLOW_FAIL);
1745 	error_uc->huc_fw.file_wanted.path = kstrdup(uc->huc.fw.file_wanted.path, ALLOW_FAIL);
1746 
1747 	/*
1748 	 * Save the GuC log and include a timestamp reference for converting the
1749 	 * log times to system times (in conjunction with the error->boottime and
1750 	 * gt->clock_frequency fields saved elsewhere).
1751 	 */
1752 	error_uc->guc.timestamp = intel_uncore_read(gt->_gt->uncore, GUCPMTIMESTAMP);
1753 	error_uc->guc.vma_log = create_vma_coredump(gt->_gt, uc->guc.log.vma,
1754 						    "GuC log buffer", compress);
1755 	error_uc->guc.vma_ctb = create_vma_coredump(gt->_gt, uc->guc.ct.vma,
1756 						    "GuC CT buffer", compress);
1757 	error_uc->guc.last_fence = uc->guc.ct.requests.last_fence;
1758 	gt_record_guc_ctb(error_uc->guc.ctb + 0, &uc->guc.ct.ctbs.send,
1759 			  uc->guc.ct.ctbs.send.desc, (struct intel_guc *)&uc->guc);
1760 	gt_record_guc_ctb(error_uc->guc.ctb + 1, &uc->guc.ct.ctbs.recv,
1761 			  uc->guc.ct.ctbs.send.desc, (struct intel_guc *)&uc->guc);
1762 
1763 	return error_uc;
1764 }
1765 
1766 /* Capture display registers. */
1767 static void gt_record_display_regs(struct intel_gt_coredump *gt)
1768 {
1769 	struct intel_uncore *uncore = gt->_gt->uncore;
1770 	struct drm_i915_private *i915 = uncore->i915;
1771 
1772 	if (DISPLAY_VER(i915) >= 6 && DISPLAY_VER(i915) < 20)
1773 		gt->derrmr = intel_uncore_read(uncore, DERRMR);
1774 
1775 	if (GRAPHICS_VER(i915) >= 8)
1776 		gt->ier = intel_uncore_read(uncore, GEN8_DE_MISC_IER);
1777 	else if (IS_VALLEYVIEW(i915))
1778 		gt->ier = intel_uncore_read(uncore, VLV_IER);
1779 	else if (HAS_PCH_SPLIT(i915))
1780 		gt->ier = intel_uncore_read(uncore, DEIER);
1781 	else if (GRAPHICS_VER(i915) == 2)
1782 		gt->ier = intel_uncore_read16(uncore, GEN2_IER);
1783 	else
1784 		gt->ier = intel_uncore_read(uncore, GEN2_IER);
1785 }
1786 
1787 /* Capture all other registers that GuC doesn't capture. */
1788 static void gt_record_global_nonguc_regs(struct intel_gt_coredump *gt)
1789 {
1790 	struct intel_uncore *uncore = gt->_gt->uncore;
1791 	struct drm_i915_private *i915 = uncore->i915;
1792 	int i;
1793 
1794 	if (IS_VALLEYVIEW(i915)) {
1795 		gt->gtier[0] = intel_uncore_read(uncore, GTIER);
1796 		gt->ngtier = 1;
1797 	} else if (GRAPHICS_VER(i915) >= 11) {
1798 		gt->gtier[0] =
1799 			intel_uncore_read(uncore,
1800 					  GEN11_RENDER_COPY_INTR_ENABLE);
1801 		gt->gtier[1] =
1802 			intel_uncore_read(uncore, GEN11_VCS_VECS_INTR_ENABLE);
1803 		gt->gtier[2] =
1804 			intel_uncore_read(uncore, GEN11_GUC_SG_INTR_ENABLE);
1805 		gt->gtier[3] =
1806 			intel_uncore_read(uncore,
1807 					  GEN11_GPM_WGBOXPERF_INTR_ENABLE);
1808 		gt->gtier[4] =
1809 			intel_uncore_read(uncore,
1810 					  GEN11_CRYPTO_RSVD_INTR_ENABLE);
1811 		gt->gtier[5] =
1812 			intel_uncore_read(uncore,
1813 					  GEN11_GUNIT_CSME_INTR_ENABLE);
1814 		gt->ngtier = 6;
1815 	} else if (GRAPHICS_VER(i915) >= 8) {
1816 		for (i = 0; i < 4; i++)
1817 			gt->gtier[i] =
1818 				intel_uncore_read(uncore, GEN8_GT_IER(i));
1819 		gt->ngtier = 4;
1820 	} else if (HAS_PCH_SPLIT(i915)) {
1821 		gt->gtier[0] = intel_uncore_read(uncore, GTIER);
1822 		gt->ngtier = 1;
1823 	}
1824 
1825 	gt->eir = intel_uncore_read(uncore, EIR);
1826 	gt->pgtbl_er = intel_uncore_read(uncore, PGTBL_ER);
1827 }
1828 
1829 /*
1830  * Capture all registers that relate to workload submission.
1831  * NOTE: In GuC submission, when GuC resets an engine, it can dump these for us
1832  */
1833 static void gt_record_global_regs(struct intel_gt_coredump *gt)
1834 {
1835 	struct intel_uncore *uncore = gt->_gt->uncore;
1836 	struct drm_i915_private *i915 = uncore->i915;
1837 	int i;
1838 
1839 	/*
1840 	 * General organization
1841 	 * 1. Registers specific to a single generation
1842 	 * 2. Registers which belong to multiple generations
1843 	 * 3. Feature specific registers.
1844 	 * 4. Everything else
1845 	 * Please try to follow the order.
1846 	 */
1847 
1848 	/* 1: Registers specific to a single generation */
1849 	if (IS_VALLEYVIEW(i915))
1850 		gt->forcewake = intel_uncore_read_fw(uncore, FORCEWAKE_VLV);
1851 
1852 	if (GRAPHICS_VER(i915) == 7)
1853 		gt->err_int = intel_uncore_read(uncore, GEN7_ERR_INT);
1854 
1855 	if (GRAPHICS_VER_FULL(i915) >= IP_VER(12, 50)) {
1856 		gt->fault_data0 = intel_gt_mcr_read_any((struct intel_gt *)gt->_gt,
1857 							XEHP_FAULT_TLB_DATA0);
1858 		gt->fault_data1 = intel_gt_mcr_read_any((struct intel_gt *)gt->_gt,
1859 							XEHP_FAULT_TLB_DATA1);
1860 	} else if (GRAPHICS_VER(i915) >= 12) {
1861 		gt->fault_data0 = intel_uncore_read(uncore,
1862 						    GEN12_FAULT_TLB_DATA0);
1863 		gt->fault_data1 = intel_uncore_read(uncore,
1864 						    GEN12_FAULT_TLB_DATA1);
1865 	} else if (GRAPHICS_VER(i915) >= 8) {
1866 		gt->fault_data0 = intel_uncore_read(uncore,
1867 						    GEN8_FAULT_TLB_DATA0);
1868 		gt->fault_data1 = intel_uncore_read(uncore,
1869 						    GEN8_FAULT_TLB_DATA1);
1870 	}
1871 
1872 	if (GRAPHICS_VER(i915) == 6) {
1873 		gt->forcewake = intel_uncore_read_fw(uncore, FORCEWAKE);
1874 		gt->gab_ctl = intel_uncore_read(uncore, GAB_CTL);
1875 		gt->gfx_mode = intel_uncore_read(uncore, GFX_MODE);
1876 	}
1877 
1878 	/* 2: Registers which belong to multiple generations */
1879 	if (GRAPHICS_VER(i915) >= 7)
1880 		gt->forcewake = intel_uncore_read_fw(uncore, FORCEWAKE_MT);
1881 
1882 	if (GRAPHICS_VER(i915) >= 6) {
1883 		if (GRAPHICS_VER(i915) < 12) {
1884 			gt->error = intel_uncore_read(uncore, ERROR_GEN6);
1885 			gt->done_reg = intel_uncore_read(uncore, DONE_REG);
1886 		}
1887 	}
1888 
1889 	/* 3: Feature specific registers */
1890 	if (IS_GRAPHICS_VER(i915, 6, 7)) {
1891 		gt->gam_ecochk = intel_uncore_read(uncore, GAM_ECOCHK);
1892 		gt->gac_eco = intel_uncore_read(uncore, GAC_ECO_BITS);
1893 	}
1894 
1895 	if (IS_GRAPHICS_VER(i915, 8, 11))
1896 		gt->gtt_cache = intel_uncore_read(uncore, HSW_GTT_CACHE_EN);
1897 
1898 	if (GRAPHICS_VER(i915) == 12)
1899 		gt->aux_err = intel_uncore_read(uncore, GEN12_AUX_ERR_DBG);
1900 
1901 	if (GRAPHICS_VER(i915) >= 12) {
1902 		for (i = 0; i < I915_MAX_SFC; i++) {
1903 			/*
1904 			 * SFC_DONE resides in the VD forcewake domain, so it
1905 			 * only exists if the corresponding VCS engine is
1906 			 * present.
1907 			 */
1908 			if ((gt->_gt->info.sfc_mask & BIT(i)) == 0 ||
1909 			    !HAS_ENGINE(gt->_gt, _VCS(i * 2)))
1910 				continue;
1911 
1912 			gt->sfc_done[i] =
1913 				intel_uncore_read(uncore, GEN12_SFC_DONE(i));
1914 		}
1915 
1916 		gt->gam_done = intel_uncore_read(uncore, GEN12_GAM_DONE);
1917 	}
1918 }
1919 
1920 static void gt_record_info(struct intel_gt_coredump *gt)
1921 {
1922 	memcpy(&gt->info, &gt->_gt->info, sizeof(struct intel_gt_info));
1923 	gt->clock_frequency = gt->_gt->clock_frequency;
1924 	gt->clock_period_ns = gt->_gt->clock_period_ns;
1925 }
1926 
1927 /*
1928  * Generate a semi-unique error code. The code is not meant to have meaning, The
1929  * code's only purpose is to try to prevent false duplicated bug reports by
1930  * grossly estimating a GPU error state.
1931  *
1932  * TODO Ideally, hashing the batchbuffer would be a very nice way to determine
1933  * the hang if we could strip the GTT offset information from it.
1934  *
1935  * It's only a small step better than a random number in its current form.
1936  */
1937 static u32 generate_ecode(const struct intel_engine_coredump *ee)
1938 {
1939 	/*
1940 	 * IPEHR would be an ideal way to detect errors, as it's the gross
1941 	 * measure of "the command that hung." However, has some very common
1942 	 * synchronization commands which almost always appear in the case
1943 	 * strictly a client bug. Use instdone to differentiate those some.
1944 	 */
1945 	return ee ? ee->ipehr ^ ee->instdone.instdone : 0;
1946 }
1947 
1948 static const char *error_msg(struct i915_gpu_coredump *error)
1949 {
1950 	struct intel_engine_coredump *first = NULL;
1951 	unsigned int hung_classes = 0;
1952 	struct intel_gt_coredump *gt;
1953 	int len;
1954 
1955 	for (gt = error->gt; gt; gt = gt->next) {
1956 		struct intel_engine_coredump *cs;
1957 
1958 		for (cs = gt->engine; cs; cs = cs->next) {
1959 			if (cs->hung) {
1960 				hung_classes |= BIT(cs->engine->uabi_class);
1961 				if (!first)
1962 					first = cs;
1963 			}
1964 		}
1965 	}
1966 
1967 	len = scnprintf(error->error_msg, sizeof(error->error_msg),
1968 			"GPU HANG: ecode %d:%x:%08x",
1969 			GRAPHICS_VER(error->i915), hung_classes,
1970 			generate_ecode(first));
1971 	if (first && first->context.pid) {
1972 		/* Just show the first executing process, more is confusing */
1973 		len += scnprintf(error->error_msg + len,
1974 				 sizeof(error->error_msg) - len,
1975 				 ", in %s [%d]",
1976 				 first->context.comm, first->context.pid);
1977 	}
1978 
1979 	return error->error_msg;
1980 }
1981 
1982 static void capture_gen(struct i915_gpu_coredump *error)
1983 {
1984 	struct drm_i915_private *i915 = error->i915;
1985 
1986 	error->wakelock = atomic_read(&i915->runtime_pm.wakeref_count);
1987 	error->suspended = pm_runtime_suspended(i915->drm.dev);
1988 
1989 	error->iommu = i915_vtd_active(i915);
1990 	error->reset_count = i915_reset_count(&i915->gpu_error);
1991 	error->suspend_count = i915->suspend_count;
1992 
1993 	i915_params_copy(&error->params, &i915->params);
1994 	intel_display_params_copy(&error->display_params);
1995 	memcpy(&error->device_info,
1996 	       INTEL_INFO(i915),
1997 	       sizeof(error->device_info));
1998 	memcpy(&error->runtime_info,
1999 	       RUNTIME_INFO(i915),
2000 	       sizeof(error->runtime_info));
2001 	memcpy(&error->display_device_info, DISPLAY_INFO(i915),
2002 	       sizeof(error->display_device_info));
2003 	memcpy(&error->display_runtime_info, DISPLAY_RUNTIME_INFO(i915),
2004 	       sizeof(error->display_runtime_info));
2005 	error->driver_caps = i915->caps;
2006 }
2007 
2008 struct i915_gpu_coredump *
2009 i915_gpu_coredump_alloc(struct drm_i915_private *i915, gfp_t gfp)
2010 {
2011 	struct i915_gpu_coredump *error;
2012 
2013 	if (!i915->params.error_capture)
2014 		return NULL;
2015 
2016 	error = kzalloc(sizeof(*error), gfp);
2017 	if (!error)
2018 		return NULL;
2019 
2020 	kref_init(&error->ref);
2021 	error->i915 = i915;
2022 
2023 	error->time = ktime_get_real();
2024 	error->boottime = ktime_get_boottime();
2025 	error->uptime = ktime_sub(ktime_get(), to_gt(i915)->last_init_time);
2026 	error->capture = jiffies;
2027 
2028 	capture_gen(error);
2029 
2030 	return error;
2031 }
2032 
2033 #define DAY_AS_SECONDS(x) (24 * 60 * 60 * (x))
2034 
2035 struct intel_gt_coredump *
2036 intel_gt_coredump_alloc(struct intel_gt *gt, gfp_t gfp, u32 dump_flags)
2037 {
2038 	struct intel_gt_coredump *gc;
2039 
2040 	gc = kzalloc(sizeof(*gc), gfp);
2041 	if (!gc)
2042 		return NULL;
2043 
2044 	gc->_gt = gt;
2045 	gc->awake = intel_gt_pm_is_awake(gt);
2046 
2047 	gt_record_display_regs(gc);
2048 	gt_record_global_nonguc_regs(gc);
2049 
2050 	/*
2051 	 * GuC dumps global, eng-class and eng-instance registers
2052 	 * (that can change as part of engine state during execution)
2053 	 * before an engine is reset due to a hung context.
2054 	 * GuC captures and reports all three groups of registers
2055 	 * together as a single set before the engine is reset.
2056 	 * Thus, if GuC triggered the context reset we retrieve
2057 	 * the register values as part of gt_record_engines.
2058 	 */
2059 	if (!(dump_flags & CORE_DUMP_FLAG_IS_GUC_CAPTURE))
2060 		gt_record_global_regs(gc);
2061 
2062 	gt_record_fences(gc);
2063 
2064 	return gc;
2065 }
2066 
2067 struct i915_vma_compress *
2068 i915_vma_capture_prepare(struct intel_gt_coredump *gt)
2069 {
2070 	struct i915_vma_compress *compress;
2071 
2072 	compress = kmalloc(sizeof(*compress), ALLOW_FAIL);
2073 	if (!compress)
2074 		return NULL;
2075 
2076 	if (!compress_init(compress)) {
2077 		kfree(compress);
2078 		return NULL;
2079 	}
2080 
2081 	return compress;
2082 }
2083 
2084 void i915_vma_capture_finish(struct intel_gt_coredump *gt,
2085 			     struct i915_vma_compress *compress)
2086 {
2087 	if (!compress)
2088 		return;
2089 
2090 	compress_fini(compress);
2091 	kfree(compress);
2092 }
2093 
2094 static struct i915_gpu_coredump *
2095 __i915_gpu_coredump(struct intel_gt *gt, intel_engine_mask_t engine_mask, u32 dump_flags)
2096 {
2097 	struct drm_i915_private *i915 = gt->i915;
2098 	struct i915_gpu_coredump *error;
2099 
2100 	/* Check if GPU capture has been disabled */
2101 	error = READ_ONCE(i915->gpu_error.first_error);
2102 	if (IS_ERR(error))
2103 		return error;
2104 
2105 	error = i915_gpu_coredump_alloc(i915, ALLOW_FAIL);
2106 	if (!error)
2107 		return ERR_PTR(-ENOMEM);
2108 
2109 	error->gt = intel_gt_coredump_alloc(gt, ALLOW_FAIL, dump_flags);
2110 	if (error->gt) {
2111 		struct i915_vma_compress *compress;
2112 
2113 		compress = i915_vma_capture_prepare(error->gt);
2114 		if (!compress) {
2115 			kfree(error->gt);
2116 			kfree(error);
2117 			return ERR_PTR(-ENOMEM);
2118 		}
2119 
2120 		if (INTEL_INFO(i915)->has_gt_uc) {
2121 			error->gt->uc = gt_record_uc(error->gt, compress);
2122 			if (error->gt->uc) {
2123 				if (dump_flags & CORE_DUMP_FLAG_IS_GUC_CAPTURE)
2124 					error->gt->uc->guc.is_guc_capture = true;
2125 				else
2126 					GEM_BUG_ON(error->gt->uc->guc.is_guc_capture);
2127 			}
2128 		}
2129 
2130 		gt_record_info(error->gt);
2131 		gt_record_engines(error->gt, engine_mask, compress, dump_flags);
2132 
2133 
2134 		i915_vma_capture_finish(error->gt, compress);
2135 
2136 		error->simulated |= error->gt->simulated;
2137 	}
2138 
2139 	error->overlay = intel_overlay_capture_error_state(i915);
2140 
2141 	return error;
2142 }
2143 
2144 static struct i915_gpu_coredump *
2145 i915_gpu_coredump(struct intel_gt *gt, intel_engine_mask_t engine_mask, u32 dump_flags)
2146 {
2147 	static DEFINE_MUTEX(capture_mutex);
2148 	int ret = mutex_lock_interruptible(&capture_mutex);
2149 	struct i915_gpu_coredump *dump;
2150 
2151 	if (ret)
2152 		return ERR_PTR(ret);
2153 
2154 	dump = __i915_gpu_coredump(gt, engine_mask, dump_flags);
2155 	mutex_unlock(&capture_mutex);
2156 
2157 	return dump;
2158 }
2159 
2160 void i915_error_state_store(struct i915_gpu_coredump *error)
2161 {
2162 	struct drm_i915_private *i915;
2163 	static bool warned;
2164 
2165 	if (IS_ERR_OR_NULL(error))
2166 		return;
2167 
2168 	i915 = error->i915;
2169 	drm_info(&i915->drm, "%s\n", error_msg(error));
2170 
2171 	if (error->simulated ||
2172 	    cmpxchg(&i915->gpu_error.first_error, NULL, error))
2173 		return;
2174 
2175 	i915_gpu_coredump_get(error);
2176 
2177 	if (!xchg(&warned, true) &&
2178 	    ktime_get_real_seconds() - DRIVER_TIMESTAMP < DAY_AS_SECONDS(180)) {
2179 		pr_info("GPU hangs can indicate a bug anywhere in the entire gfx stack, including userspace.\n");
2180 		pr_info("Please file a _new_ bug report at https://gitlab.freedesktop.org/drm/intel/issues/new.\n");
2181 		pr_info("Please see https://drm.pages.freedesktop.org/intel-docs/how-to-file-i915-bugs.html for details.\n");
2182 		pr_info("drm/i915 developers can then reassign to the right component if it's not a kernel issue.\n");
2183 		pr_info("The GPU crash dump is required to analyze GPU hangs, so please always attach it.\n");
2184 		pr_info("GPU crash dump saved to /sys/class/drm/card%d/error\n",
2185 			i915->drm.primary->index);
2186 	}
2187 }
2188 
2189 /**
2190  * i915_capture_error_state - capture an error record for later analysis
2191  * @gt: intel_gt which originated the hang
2192  * @engine_mask: hung engines
2193  * @dump_flags: dump flags
2194  *
2195  * Should be called when an error is detected (either a hang or an error
2196  * interrupt) to capture error state from the time of the error.  Fills
2197  * out a structure which becomes available in debugfs for user level tools
2198  * to pick up.
2199  */
2200 void i915_capture_error_state(struct intel_gt *gt,
2201 			      intel_engine_mask_t engine_mask, u32 dump_flags)
2202 {
2203 	struct i915_gpu_coredump *error;
2204 
2205 	error = i915_gpu_coredump(gt, engine_mask, dump_flags);
2206 	if (IS_ERR(error)) {
2207 		cmpxchg(&gt->i915->gpu_error.first_error, NULL, error);
2208 		return;
2209 	}
2210 
2211 	i915_error_state_store(error);
2212 	i915_gpu_coredump_put(error);
2213 }
2214 
2215 static struct i915_gpu_coredump *
2216 i915_first_error_state(struct drm_i915_private *i915)
2217 {
2218 	struct i915_gpu_coredump *error;
2219 
2220 	spin_lock_irq(&i915->gpu_error.lock);
2221 	error = i915->gpu_error.first_error;
2222 	if (!IS_ERR_OR_NULL(error))
2223 		i915_gpu_coredump_get(error);
2224 	spin_unlock_irq(&i915->gpu_error.lock);
2225 
2226 	return error;
2227 }
2228 
2229 void i915_reset_error_state(struct drm_i915_private *i915)
2230 {
2231 	struct i915_gpu_coredump *error;
2232 
2233 	spin_lock_irq(&i915->gpu_error.lock);
2234 	error = i915->gpu_error.first_error;
2235 	if (error != ERR_PTR(-ENODEV)) /* if disabled, always disabled */
2236 		i915->gpu_error.first_error = NULL;
2237 	spin_unlock_irq(&i915->gpu_error.lock);
2238 
2239 	if (!IS_ERR_OR_NULL(error))
2240 		i915_gpu_coredump_put(error);
2241 }
2242 
2243 void i915_disable_error_state(struct drm_i915_private *i915, int err)
2244 {
2245 	spin_lock_irq(&i915->gpu_error.lock);
2246 	if (!i915->gpu_error.first_error)
2247 		i915->gpu_error.first_error = ERR_PTR(err);
2248 	spin_unlock_irq(&i915->gpu_error.lock);
2249 }
2250 
2251 #if IS_ENABLED(CONFIG_DRM_I915_DEBUG_GEM)
2252 void intel_klog_error_capture(struct intel_gt *gt,
2253 			      intel_engine_mask_t engine_mask)
2254 {
2255 	static int g_count;
2256 	struct drm_i915_private *i915 = gt->i915;
2257 	struct i915_gpu_coredump *error;
2258 	intel_wakeref_t wakeref;
2259 	size_t buf_size = PAGE_SIZE * 128;
2260 	size_t pos_err;
2261 	char *buf, *ptr, *next;
2262 	int l_count = g_count++;
2263 	int line = 0;
2264 
2265 	/* Can't allocate memory during a reset */
2266 	if (test_bit(I915_RESET_BACKOFF, &gt->reset.flags)) {
2267 		drm_err(&gt->i915->drm, "[Capture/%d.%d] Inside GT reset, skipping error capture :(\n",
2268 			l_count, line++);
2269 		return;
2270 	}
2271 
2272 	error = READ_ONCE(i915->gpu_error.first_error);
2273 	if (error) {
2274 		drm_err(&i915->drm, "[Capture/%d.%d] Clearing existing error capture first...\n",
2275 			l_count, line++);
2276 		i915_reset_error_state(i915);
2277 	}
2278 
2279 	with_intel_runtime_pm(&i915->runtime_pm, wakeref)
2280 		error = i915_gpu_coredump(gt, engine_mask, CORE_DUMP_FLAG_NONE);
2281 
2282 	if (IS_ERR(error)) {
2283 		drm_err(&i915->drm, "[Capture/%d.%d] Failed to capture error capture: %ld!\n",
2284 			l_count, line++, PTR_ERR(error));
2285 		return;
2286 	}
2287 
2288 	buf = kvmalloc(buf_size, GFP_KERNEL);
2289 	if (!buf) {
2290 		drm_err(&i915->drm, "[Capture/%d.%d] Failed to allocate buffer for error capture!\n",
2291 			l_count, line++);
2292 		i915_gpu_coredump_put(error);
2293 		return;
2294 	}
2295 
2296 	drm_info(&i915->drm, "[Capture/%d.%d] Dumping i915 error capture for %ps...\n",
2297 		 l_count, line++, __builtin_return_address(0));
2298 
2299 	/* Largest string length safe to print via dmesg */
2300 #	define MAX_CHUNK	800
2301 
2302 	pos_err = 0;
2303 	while (1) {
2304 		ssize_t got = i915_gpu_coredump_copy_to_buffer(error, buf, pos_err, buf_size - 1);
2305 
2306 		if (got <= 0)
2307 			break;
2308 
2309 		buf[got] = 0;
2310 		pos_err += got;
2311 
2312 		ptr = buf;
2313 		while (got > 0) {
2314 			size_t count;
2315 			char tag[2];
2316 
2317 			next = strnchr(ptr, got, '\n');
2318 			if (next) {
2319 				count = next - ptr;
2320 				*next = 0;
2321 				tag[0] = '>';
2322 				tag[1] = '<';
2323 			} else {
2324 				count = got;
2325 				tag[0] = '}';
2326 				tag[1] = '{';
2327 			}
2328 
2329 			if (count > MAX_CHUNK) {
2330 				size_t pos;
2331 				char *ptr2 = ptr;
2332 
2333 				for (pos = MAX_CHUNK; pos < count; pos += MAX_CHUNK) {
2334 					char chr = ptr[pos];
2335 
2336 					ptr[pos] = 0;
2337 					drm_info(&i915->drm, "[Capture/%d.%d] }%s{\n",
2338 						 l_count, line++, ptr2);
2339 					ptr[pos] = chr;
2340 					ptr2 = ptr + pos;
2341 
2342 					/*
2343 					 * If spewing large amounts of data via a serial console,
2344 					 * this can be a very slow process. So be friendly and try
2345 					 * not to cause 'softlockup on CPU' problems.
2346 					 */
2347 					cond_resched();
2348 				}
2349 
2350 				if (ptr2 < (ptr + count))
2351 					drm_info(&i915->drm, "[Capture/%d.%d] %c%s%c\n",
2352 						 l_count, line++, tag[0], ptr2, tag[1]);
2353 				else if (tag[0] == '>')
2354 					drm_info(&i915->drm, "[Capture/%d.%d] ><\n",
2355 						 l_count, line++);
2356 			} else {
2357 				drm_info(&i915->drm, "[Capture/%d.%d] %c%s%c\n",
2358 					 l_count, line++, tag[0], ptr, tag[1]);
2359 			}
2360 
2361 			ptr = next;
2362 			got -= count;
2363 			if (next) {
2364 				ptr++;
2365 				got--;
2366 			}
2367 
2368 			/* As above. */
2369 			cond_resched();
2370 		}
2371 
2372 		if (got)
2373 			drm_info(&i915->drm, "[Capture/%d.%d] Got %zd bytes remaining!\n",
2374 				 l_count, line++, got);
2375 	}
2376 
2377 	kvfree(buf);
2378 
2379 	drm_info(&i915->drm, "[Capture/%d.%d] Dumped %zd bytes\n", l_count, line++, pos_err);
2380 }
2381 #endif
2382 
2383 static ssize_t gpu_state_read(struct file *file, char __user *ubuf,
2384 			      size_t count, loff_t *pos)
2385 {
2386 	struct i915_gpu_coredump *error;
2387 	ssize_t ret;
2388 	void *buf;
2389 
2390 	error = file->private_data;
2391 	if (!error)
2392 		return 0;
2393 
2394 	/* Bounce buffer required because of kernfs __user API convenience. */
2395 	buf = kmalloc(count, GFP_KERNEL);
2396 	if (!buf)
2397 		return -ENOMEM;
2398 
2399 	ret = i915_gpu_coredump_copy_to_buffer(error, buf, *pos, count);
2400 	if (ret <= 0)
2401 		goto out;
2402 
2403 	if (!copy_to_user(ubuf, buf, ret))
2404 		*pos += ret;
2405 	else
2406 		ret = -EFAULT;
2407 
2408 out:
2409 	kfree(buf);
2410 	return ret;
2411 }
2412 
2413 static int gpu_state_release(struct inode *inode, struct file *file)
2414 {
2415 	i915_gpu_coredump_put(file->private_data);
2416 	return 0;
2417 }
2418 
2419 static int i915_gpu_info_open(struct inode *inode, struct file *file)
2420 {
2421 	struct drm_i915_private *i915 = inode->i_private;
2422 	struct i915_gpu_coredump *gpu;
2423 	intel_wakeref_t wakeref;
2424 
2425 	gpu = NULL;
2426 	with_intel_runtime_pm(&i915->runtime_pm, wakeref)
2427 		gpu = i915_gpu_coredump(to_gt(i915), ALL_ENGINES, CORE_DUMP_FLAG_NONE);
2428 
2429 	if (IS_ERR(gpu))
2430 		return PTR_ERR(gpu);
2431 
2432 	file->private_data = gpu;
2433 	return 0;
2434 }
2435 
2436 static const struct file_operations i915_gpu_info_fops = {
2437 	.owner = THIS_MODULE,
2438 	.open = i915_gpu_info_open,
2439 	.read = gpu_state_read,
2440 	.llseek = default_llseek,
2441 	.release = gpu_state_release,
2442 };
2443 
2444 static ssize_t
2445 i915_error_state_write(struct file *filp,
2446 		       const char __user *ubuf,
2447 		       size_t cnt,
2448 		       loff_t *ppos)
2449 {
2450 	struct i915_gpu_coredump *error = filp->private_data;
2451 
2452 	if (!error)
2453 		return 0;
2454 
2455 	drm_dbg(&error->i915->drm, "Resetting error state\n");
2456 	i915_reset_error_state(error->i915);
2457 
2458 	return cnt;
2459 }
2460 
2461 static int i915_error_state_open(struct inode *inode, struct file *file)
2462 {
2463 	struct i915_gpu_coredump *error;
2464 
2465 	error = i915_first_error_state(inode->i_private);
2466 	if (IS_ERR(error))
2467 		return PTR_ERR(error);
2468 
2469 	file->private_data  = error;
2470 	return 0;
2471 }
2472 
2473 static const struct file_operations i915_error_state_fops = {
2474 	.owner = THIS_MODULE,
2475 	.open = i915_error_state_open,
2476 	.read = gpu_state_read,
2477 	.write = i915_error_state_write,
2478 	.llseek = default_llseek,
2479 	.release = gpu_state_release,
2480 };
2481 
2482 void i915_gpu_error_debugfs_register(struct drm_i915_private *i915)
2483 {
2484 	struct drm_minor *minor = i915->drm.primary;
2485 
2486 	debugfs_create_file("i915_error_state", 0644, minor->debugfs_root, i915,
2487 			    &i915_error_state_fops);
2488 	debugfs_create_file("i915_gpu_info", 0644, minor->debugfs_root, i915,
2489 			    &i915_gpu_info_fops);
2490 }
2491 
2492 static ssize_t error_state_read(struct file *filp, struct kobject *kobj,
2493 				struct bin_attribute *attr, char *buf,
2494 				loff_t off, size_t count)
2495 {
2496 
2497 	struct device *kdev = kobj_to_dev(kobj);
2498 	struct drm_i915_private *i915 = kdev_minor_to_i915(kdev);
2499 	struct i915_gpu_coredump *gpu;
2500 	ssize_t ret = 0;
2501 
2502 	/*
2503 	 * FIXME: Concurrent clients triggering resets and reading + clearing
2504 	 * dumps can cause inconsistent sysfs reads when a user calls in with a
2505 	 * non-zero offset to complete a prior partial read but the
2506 	 * gpu_coredump has been cleared or replaced.
2507 	 */
2508 
2509 	gpu = i915_first_error_state(i915);
2510 	if (IS_ERR(gpu)) {
2511 		ret = PTR_ERR(gpu);
2512 	} else if (gpu) {
2513 		ret = i915_gpu_coredump_copy_to_buffer(gpu, buf, off, count);
2514 		i915_gpu_coredump_put(gpu);
2515 	} else {
2516 		const char *str = "No error state collected\n";
2517 		size_t len = strlen(str);
2518 
2519 		if (off < len) {
2520 			ret = min_t(size_t, count, len - off);
2521 			memcpy(buf, str + off, ret);
2522 		}
2523 	}
2524 
2525 	return ret;
2526 }
2527 
2528 static ssize_t error_state_write(struct file *file, struct kobject *kobj,
2529 				 struct bin_attribute *attr, char *buf,
2530 				 loff_t off, size_t count)
2531 {
2532 	struct device *kdev = kobj_to_dev(kobj);
2533 	struct drm_i915_private *dev_priv = kdev_minor_to_i915(kdev);
2534 
2535 	drm_dbg(&dev_priv->drm, "Resetting error state\n");
2536 	i915_reset_error_state(dev_priv);
2537 
2538 	return count;
2539 }
2540 
2541 static const struct bin_attribute error_state_attr = {
2542 	.attr.name = "error",
2543 	.attr.mode = S_IRUSR | S_IWUSR,
2544 	.size = 0,
2545 	.read = error_state_read,
2546 	.write = error_state_write,
2547 };
2548 
2549 void i915_gpu_error_sysfs_setup(struct drm_i915_private *i915)
2550 {
2551 	struct device *kdev = i915->drm.primary->kdev;
2552 
2553 	if (sysfs_create_bin_file(&kdev->kobj, &error_state_attr))
2554 		drm_err(&i915->drm, "error_state sysfs setup failed\n");
2555 }
2556 
2557 void i915_gpu_error_sysfs_teardown(struct drm_i915_private *i915)
2558 {
2559 	struct device *kdev = i915->drm.primary->kdev;
2560 
2561 	sysfs_remove_bin_file(&kdev->kobj, &error_state_attr);
2562 }
2563