xref: /linux/drivers/gpu/drm/i915/i915_gpu_error.c (revision c532de5a67a70f8533d495f8f2aaa9a0491c3ad0)
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 	struct intel_display *display = &m->i915->display;
664 
665 	i915_params_dump(params, &p);
666 	intel_display_params_dump(display, &p);
667 }
668 
669 static void err_print_pciid(struct drm_i915_error_state_buf *m,
670 			    struct drm_i915_private *i915)
671 {
672 	struct pci_dev *pdev = to_pci_dev(i915->drm.dev);
673 
674 	err_printf(m, "PCI ID: 0x%04x\n", pdev->device);
675 	err_printf(m, "PCI Revision: 0x%02x\n", pdev->revision);
676 	err_printf(m, "PCI Subsystem: %04x:%04x\n",
677 		   pdev->subsystem_vendor,
678 		   pdev->subsystem_device);
679 }
680 
681 static void err_print_guc_ctb(struct drm_i915_error_state_buf *m,
682 			      const char *name,
683 			      const struct intel_ctb_coredump *ctb)
684 {
685 	if (!ctb->size)
686 		return;
687 
688 	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",
689 		   name, ctb->raw_status, ctb->raw_head, ctb->raw_tail,
690 		   ctb->head, ctb->tail, ctb->desc_offset, ctb->cmds_offset, ctb->size);
691 }
692 
693 static void err_print_uc(struct drm_i915_error_state_buf *m,
694 			 const struct intel_uc_coredump *error_uc)
695 {
696 	struct drm_printer p = i915_error_printer(m);
697 
698 	intel_uc_fw_dump(&error_uc->guc_fw, &p);
699 	intel_uc_fw_dump(&error_uc->huc_fw, &p);
700 	err_printf(m, "GuC timestamp: 0x%08x\n", error_uc->guc.timestamp);
701 	intel_gpu_error_print_vma(m, NULL, error_uc->guc.vma_log);
702 	err_printf(m, "GuC CTB fence: %d\n", error_uc->guc.last_fence);
703 	err_print_guc_ctb(m, "Send", error_uc->guc.ctb + 0);
704 	err_print_guc_ctb(m, "Recv", error_uc->guc.ctb + 1);
705 	intel_gpu_error_print_vma(m, NULL, error_uc->guc.vma_ctb);
706 }
707 
708 static void err_free_sgl(struct scatterlist *sgl)
709 {
710 	while (sgl) {
711 		struct scatterlist *sg;
712 
713 		for (sg = sgl; !sg_is_chain(sg); sg++) {
714 			kfree(sg_virt(sg));
715 			if (sg_is_last(sg))
716 				break;
717 		}
718 
719 		sg = sg_is_last(sg) ? NULL : sg_chain_ptr(sg);
720 		free_page((unsigned long)sgl);
721 		sgl = sg;
722 	}
723 }
724 
725 static void err_print_gt_info(struct drm_i915_error_state_buf *m,
726 			      struct intel_gt_coredump *gt)
727 {
728 	struct drm_printer p = i915_error_printer(m);
729 
730 	intel_gt_info_print(&gt->info, &p);
731 	intel_sseu_print_topology(gt->_gt->i915, &gt->info.sseu, &p);
732 }
733 
734 static void err_print_gt_display(struct drm_i915_error_state_buf *m,
735 				 struct intel_gt_coredump *gt)
736 {
737 	err_printf(m, "IER: 0x%08x\n", gt->ier);
738 	err_printf(m, "DERRMR: 0x%08x\n", gt->derrmr);
739 }
740 
741 static void err_print_gt_global_nonguc(struct drm_i915_error_state_buf *m,
742 				       struct intel_gt_coredump *gt)
743 {
744 	int i;
745 
746 	err_printf(m, "GT awake: %s\n", str_yes_no(gt->awake));
747 	err_printf(m, "CS timestamp frequency: %u Hz, %d ns\n",
748 		   gt->clock_frequency, gt->clock_period_ns);
749 	err_printf(m, "EIR: 0x%08x\n", gt->eir);
750 	err_printf(m, "PGTBL_ER: 0x%08x\n", gt->pgtbl_er);
751 
752 	for (i = 0; i < gt->ngtier; i++)
753 		err_printf(m, "GTIER[%d]: 0x%08x\n", i, gt->gtier[i]);
754 }
755 
756 static void err_print_gt_global(struct drm_i915_error_state_buf *m,
757 				struct intel_gt_coredump *gt)
758 {
759 	err_printf(m, "FORCEWAKE: 0x%08x\n", gt->forcewake);
760 
761 	if (IS_GRAPHICS_VER(m->i915, 6, 11)) {
762 		err_printf(m, "ERROR: 0x%08x\n", gt->error);
763 		err_printf(m, "DONE_REG: 0x%08x\n", gt->done_reg);
764 	}
765 
766 	if (GRAPHICS_VER(m->i915) >= 8)
767 		err_printf(m, "FAULT_TLB_DATA: 0x%08x 0x%08x\n",
768 			   gt->fault_data1, gt->fault_data0);
769 
770 	if (GRAPHICS_VER(m->i915) == 7)
771 		err_printf(m, "ERR_INT: 0x%08x\n", gt->err_int);
772 
773 	if (IS_GRAPHICS_VER(m->i915, 8, 11))
774 		err_printf(m, "GTT_CACHE_EN: 0x%08x\n", gt->gtt_cache);
775 
776 	if (GRAPHICS_VER(m->i915) == 12)
777 		err_printf(m, "AUX_ERR_DBG: 0x%08x\n", gt->aux_err);
778 
779 	if (GRAPHICS_VER(m->i915) >= 12) {
780 		int i;
781 
782 		for (i = 0; i < I915_MAX_SFC; i++) {
783 			/*
784 			 * SFC_DONE resides in the VD forcewake domain, so it
785 			 * only exists if the corresponding VCS engine is
786 			 * present.
787 			 */
788 			if ((gt->_gt->info.sfc_mask & BIT(i)) == 0 ||
789 			    !HAS_ENGINE(gt->_gt, _VCS(i * 2)))
790 				continue;
791 
792 			err_printf(m, "  SFC_DONE[%d]: 0x%08x\n", i,
793 				   gt->sfc_done[i]);
794 		}
795 
796 		err_printf(m, "  GAM_DONE: 0x%08x\n", gt->gam_done);
797 	}
798 }
799 
800 static void err_print_gt_fences(struct drm_i915_error_state_buf *m,
801 				struct intel_gt_coredump *gt)
802 {
803 	int i;
804 
805 	for (i = 0; i < gt->nfence; i++)
806 		err_printf(m, "  fence[%d] = %08llx\n", i, gt->fence[i]);
807 }
808 
809 static void err_print_gt_engines(struct drm_i915_error_state_buf *m,
810 				 struct intel_gt_coredump *gt)
811 {
812 	const struct intel_engine_coredump *ee;
813 
814 	for (ee = gt->engine; ee; ee = ee->next) {
815 		const struct i915_vma_coredump *vma;
816 
817 		if (gt->uc && gt->uc->guc.is_guc_capture) {
818 			if (ee->guc_capture_node)
819 				intel_guc_capture_print_engine_node(m, ee);
820 			else
821 				err_printf(m, "  Missing GuC capture node for %s\n",
822 					   ee->engine->name);
823 		} else {
824 			error_print_engine(m, ee);
825 		}
826 
827 		err_printf(m, "  hung: %u\n", ee->hung);
828 		err_printf(m, "  engine reset count: %u\n", ee->reset_count);
829 		error_print_context(m, "  Active context: ", &ee->context);
830 
831 		for (vma = ee->vma; vma; vma = vma->next)
832 			intel_gpu_error_print_vma(m, ee->engine, vma);
833 	}
834 
835 }
836 
837 static void __err_print_to_sgl(struct drm_i915_error_state_buf *m,
838 			       struct i915_gpu_coredump *error)
839 {
840 	struct drm_printer p = i915_error_printer(m);
841 	const struct intel_engine_coredump *ee;
842 	struct timespec64 ts;
843 
844 	if (*error->error_msg)
845 		err_printf(m, "%s\n", error->error_msg);
846 	err_printf(m, "Kernel: %s %s\n",
847 		   init_utsname()->release,
848 		   init_utsname()->machine);
849 	err_printf(m, "Driver: %s\n", DRIVER_DATE);
850 	ts = ktime_to_timespec64(error->time);
851 	err_printf(m, "Time: %lld s %ld us\n",
852 		   (s64)ts.tv_sec, ts.tv_nsec / NSEC_PER_USEC);
853 	ts = ktime_to_timespec64(error->boottime);
854 	err_printf(m, "Boottime: %lld s %ld us\n",
855 		   (s64)ts.tv_sec, ts.tv_nsec / NSEC_PER_USEC);
856 	ts = ktime_to_timespec64(error->uptime);
857 	err_printf(m, "Uptime: %lld s %ld us\n",
858 		   (s64)ts.tv_sec, ts.tv_nsec / NSEC_PER_USEC);
859 	err_printf(m, "Capture: %lu jiffies; %d ms ago\n",
860 		   error->capture, jiffies_to_msecs(jiffies - error->capture));
861 
862 	for (ee = error->gt ? error->gt->engine : NULL; ee; ee = ee->next)
863 		err_printf(m, "Active process (on ring %s): %s [%d]\n",
864 			   ee->engine->name,
865 			   ee->context.comm,
866 			   ee->context.pid);
867 
868 	err_printf(m, "Reset count: %u\n", error->reset_count);
869 	err_printf(m, "Suspend count: %u\n", error->suspend_count);
870 	err_printf(m, "Platform: %s\n", intel_platform_name(error->device_info.platform));
871 	err_printf(m, "Subplatform: 0x%x\n",
872 		   intel_subplatform(&error->runtime_info,
873 				     error->device_info.platform));
874 	err_print_pciid(m, m->i915);
875 
876 	err_printf(m, "IOMMU enabled?: %d\n", error->iommu);
877 
878 	intel_dmc_print_error_state(&p, m->i915);
879 
880 	err_printf(m, "RPM wakelock: %s\n", str_yes_no(error->wakelock));
881 	err_printf(m, "PM suspended: %s\n", str_yes_no(error->suspended));
882 
883 	if (error->gt) {
884 		bool print_guc_capture = false;
885 
886 		if (error->gt->uc && error->gt->uc->guc.is_guc_capture)
887 			print_guc_capture = true;
888 
889 		err_print_gt_display(m, error->gt);
890 		err_print_gt_global_nonguc(m, error->gt);
891 		err_print_gt_fences(m, error->gt);
892 
893 		/*
894 		 * GuC dumped global, eng-class and eng-instance registers together
895 		 * as part of engine state dump so we print in err_print_gt_engines
896 		 */
897 		if (!print_guc_capture)
898 			err_print_gt_global(m, error->gt);
899 
900 		err_print_gt_engines(m, error->gt);
901 
902 		if (error->gt->uc)
903 			err_print_uc(m, error->gt->uc);
904 
905 		err_print_gt_info(m, error->gt);
906 	}
907 
908 	if (error->overlay)
909 		intel_overlay_print_error_state(&p, error->overlay);
910 
911 	err_print_capabilities(m, error);
912 	err_print_params(m, &error->params);
913 }
914 
915 static int err_print_to_sgl(struct i915_gpu_coredump *error)
916 {
917 	struct drm_i915_error_state_buf m;
918 
919 	if (IS_ERR(error))
920 		return PTR_ERR(error);
921 
922 	if (READ_ONCE(error->sgl))
923 		return 0;
924 
925 	memset(&m, 0, sizeof(m));
926 	m.i915 = error->i915;
927 
928 	__err_print_to_sgl(&m, error);
929 
930 	if (m.buf) {
931 		__sg_set_buf(m.cur++, m.buf, m.bytes, m.iter);
932 		m.bytes = 0;
933 		m.buf = NULL;
934 	}
935 	if (m.cur) {
936 		GEM_BUG_ON(m.end < m.cur);
937 		sg_mark_end(m.cur - 1);
938 	}
939 	GEM_BUG_ON(m.sgl && !m.cur);
940 
941 	if (m.err) {
942 		err_free_sgl(m.sgl);
943 		return m.err;
944 	}
945 
946 	if (cmpxchg(&error->sgl, NULL, m.sgl))
947 		err_free_sgl(m.sgl);
948 
949 	return 0;
950 }
951 
952 ssize_t i915_gpu_coredump_copy_to_buffer(struct i915_gpu_coredump *error,
953 					 char *buf, loff_t off, size_t rem)
954 {
955 	struct scatterlist *sg;
956 	size_t count;
957 	loff_t pos;
958 	int err;
959 
960 	if (!error || !rem)
961 		return 0;
962 
963 	err = err_print_to_sgl(error);
964 	if (err)
965 		return err;
966 
967 	sg = READ_ONCE(error->fit);
968 	if (!sg || off < sg->dma_address)
969 		sg = error->sgl;
970 	if (!sg)
971 		return 0;
972 
973 	pos = sg->dma_address;
974 	count = 0;
975 	do {
976 		size_t len, start;
977 
978 		if (sg_is_chain(sg)) {
979 			sg = sg_chain_ptr(sg);
980 			GEM_BUG_ON(sg_is_chain(sg));
981 		}
982 
983 		len = sg->length;
984 		if (pos + len <= off) {
985 			pos += len;
986 			continue;
987 		}
988 
989 		start = sg->offset;
990 		if (pos < off) {
991 			GEM_BUG_ON(off - pos > len);
992 			len -= off - pos;
993 			start += off - pos;
994 			pos = off;
995 		}
996 
997 		len = min(len, rem);
998 		GEM_BUG_ON(!len || len > sg->length);
999 
1000 		memcpy(buf, page_address(sg_page(sg)) + start, len);
1001 
1002 		count += len;
1003 		pos += len;
1004 
1005 		buf += len;
1006 		rem -= len;
1007 		if (!rem) {
1008 			WRITE_ONCE(error->fit, sg);
1009 			break;
1010 		}
1011 	} while (!sg_is_last(sg++));
1012 
1013 	return count;
1014 }
1015 
1016 static void i915_vma_coredump_free(struct i915_vma_coredump *vma)
1017 {
1018 	while (vma) {
1019 		struct i915_vma_coredump *next = vma->next;
1020 		struct page *page, *n;
1021 
1022 		list_for_each_entry_safe(page, n, &vma->page_list, lru) {
1023 			list_del_init(&page->lru);
1024 			__free_page(page);
1025 		}
1026 
1027 		kfree(vma);
1028 		vma = next;
1029 	}
1030 }
1031 
1032 static void cleanup_params(struct i915_gpu_coredump *error)
1033 {
1034 	i915_params_free(&error->params);
1035 	intel_display_params_free(&error->display_params);
1036 }
1037 
1038 static void cleanup_uc(struct intel_uc_coredump *uc)
1039 {
1040 	kfree(uc->guc_fw.file_selected.path);
1041 	kfree(uc->huc_fw.file_selected.path);
1042 	kfree(uc->guc_fw.file_wanted.path);
1043 	kfree(uc->huc_fw.file_wanted.path);
1044 	i915_vma_coredump_free(uc->guc.vma_log);
1045 	i915_vma_coredump_free(uc->guc.vma_ctb);
1046 
1047 	kfree(uc);
1048 }
1049 
1050 static void cleanup_gt(struct intel_gt_coredump *gt)
1051 {
1052 	while (gt->engine) {
1053 		struct intel_engine_coredump *ee = gt->engine;
1054 
1055 		gt->engine = ee->next;
1056 
1057 		i915_vma_coredump_free(ee->vma);
1058 		intel_guc_capture_free_node(ee);
1059 		kfree(ee);
1060 	}
1061 
1062 	if (gt->uc)
1063 		cleanup_uc(gt->uc);
1064 
1065 	kfree(gt);
1066 }
1067 
1068 void __i915_gpu_coredump_free(struct kref *error_ref)
1069 {
1070 	struct i915_gpu_coredump *error =
1071 		container_of(error_ref, typeof(*error), ref);
1072 
1073 	while (error->gt) {
1074 		struct intel_gt_coredump *gt = error->gt;
1075 
1076 		error->gt = gt->next;
1077 		cleanup_gt(gt);
1078 	}
1079 
1080 	kfree(error->overlay);
1081 
1082 	cleanup_params(error);
1083 
1084 	err_free_sgl(error->sgl);
1085 	kfree(error);
1086 }
1087 
1088 static struct i915_vma_coredump *
1089 i915_vma_coredump_create(const struct intel_gt *gt,
1090 			 const struct i915_vma_resource *vma_res,
1091 			 struct i915_vma_compress *compress,
1092 			 const char *name)
1093 
1094 {
1095 	struct i915_ggtt *ggtt = gt->ggtt;
1096 	const u64 slot = ggtt->error_capture.start;
1097 	struct i915_vma_coredump *dst;
1098 	struct sgt_iter iter;
1099 	int ret;
1100 
1101 	might_sleep();
1102 
1103 	if (!vma_res || !vma_res->bi.pages || !compress)
1104 		return NULL;
1105 
1106 	dst = kmalloc(sizeof(*dst), ALLOW_FAIL);
1107 	if (!dst)
1108 		return NULL;
1109 
1110 	if (!compress_start(compress)) {
1111 		kfree(dst);
1112 		return NULL;
1113 	}
1114 
1115 	INIT_LIST_HEAD(&dst->page_list);
1116 	strcpy(dst->name, name);
1117 	dst->next = NULL;
1118 
1119 	dst->gtt_offset = vma_res->start;
1120 	dst->gtt_size = vma_res->node_size;
1121 	dst->gtt_page_sizes = vma_res->page_sizes_gtt;
1122 	dst->unused = 0;
1123 
1124 	ret = -EINVAL;
1125 	if (drm_mm_node_allocated(&ggtt->error_capture)) {
1126 		void __iomem *s;
1127 		dma_addr_t dma;
1128 
1129 		for_each_sgt_daddr(dma, iter, vma_res->bi.pages) {
1130 			mutex_lock(&ggtt->error_mutex);
1131 			if (ggtt->vm.raw_insert_page)
1132 				ggtt->vm.raw_insert_page(&ggtt->vm, dma, slot,
1133 							 i915_gem_get_pat_index(gt->i915,
1134 										I915_CACHE_NONE),
1135 							 0);
1136 			else
1137 				ggtt->vm.insert_page(&ggtt->vm, dma, slot,
1138 						     i915_gem_get_pat_index(gt->i915,
1139 									    I915_CACHE_NONE),
1140 						     0);
1141 			mb();
1142 
1143 			s = io_mapping_map_wc(&ggtt->iomap, slot, PAGE_SIZE);
1144 			ret = compress_page(compress,
1145 					    (void  __force *)s, dst,
1146 					    true);
1147 			io_mapping_unmap(s);
1148 
1149 			mb();
1150 			ggtt->vm.clear_range(&ggtt->vm, slot, PAGE_SIZE);
1151 			mutex_unlock(&ggtt->error_mutex);
1152 			if (ret)
1153 				break;
1154 		}
1155 	} else if (vma_res->bi.lmem) {
1156 		struct intel_memory_region *mem = vma_res->mr;
1157 		dma_addr_t dma;
1158 
1159 		for_each_sgt_daddr(dma, iter, vma_res->bi.pages) {
1160 			dma_addr_t offset = dma - mem->region.start;
1161 			void __iomem *s;
1162 
1163 			if (offset + PAGE_SIZE > resource_size(&mem->io)) {
1164 				ret = -EINVAL;
1165 				break;
1166 			}
1167 
1168 			s = io_mapping_map_wc(&mem->iomap, offset, PAGE_SIZE);
1169 			ret = compress_page(compress,
1170 					    (void __force *)s, dst,
1171 					    true);
1172 			io_mapping_unmap(s);
1173 			if (ret)
1174 				break;
1175 		}
1176 	} else {
1177 		struct page *page;
1178 
1179 		for_each_sgt_page(page, iter, vma_res->bi.pages) {
1180 			void *s;
1181 
1182 			drm_clflush_pages(&page, 1);
1183 
1184 			s = kmap_local_page(page);
1185 			ret = compress_page(compress, s, dst, false);
1186 			kunmap_local(s);
1187 
1188 			drm_clflush_pages(&page, 1);
1189 
1190 			if (ret)
1191 				break;
1192 		}
1193 	}
1194 
1195 	if (ret || compress_flush(compress, dst)) {
1196 		struct page *page, *n;
1197 
1198 		list_for_each_entry_safe_reverse(page, n, &dst->page_list, lru) {
1199 			list_del_init(&page->lru);
1200 			pool_free(&compress->pool, page_address(page));
1201 		}
1202 
1203 		kfree(dst);
1204 		dst = NULL;
1205 	}
1206 	compress_finish(compress);
1207 
1208 	return dst;
1209 }
1210 
1211 static void gt_record_fences(struct intel_gt_coredump *gt)
1212 {
1213 	struct i915_ggtt *ggtt = gt->_gt->ggtt;
1214 	struct intel_uncore *uncore = gt->_gt->uncore;
1215 	int i;
1216 
1217 	if (GRAPHICS_VER(uncore->i915) >= 6) {
1218 		for (i = 0; i < ggtt->num_fences; i++)
1219 			gt->fence[i] =
1220 				intel_uncore_read64(uncore,
1221 						    FENCE_REG_GEN6_LO(i));
1222 	} else if (GRAPHICS_VER(uncore->i915) >= 4) {
1223 		for (i = 0; i < ggtt->num_fences; i++)
1224 			gt->fence[i] =
1225 				intel_uncore_read64(uncore,
1226 						    FENCE_REG_965_LO(i));
1227 	} else {
1228 		for (i = 0; i < ggtt->num_fences; i++)
1229 			gt->fence[i] =
1230 				intel_uncore_read(uncore, FENCE_REG(i));
1231 	}
1232 	gt->nfence = i;
1233 }
1234 
1235 static void engine_record_registers(struct intel_engine_coredump *ee)
1236 {
1237 	const struct intel_engine_cs *engine = ee->engine;
1238 	struct drm_i915_private *i915 = engine->i915;
1239 
1240 	if (GRAPHICS_VER(i915) >= 6) {
1241 		ee->rc_psmi = ENGINE_READ(engine, RING_PSMI_CTL);
1242 
1243 		/*
1244 		 * For the media GT, this ring fault register is not replicated,
1245 		 * so don't do multicast/replicated register read/write
1246 		 * operation on it.
1247 		 */
1248 		if (MEDIA_VER(i915) >= 13 && engine->gt->type == GT_MEDIA)
1249 			ee->fault_reg = intel_uncore_read(engine->uncore,
1250 							  XELPMP_RING_FAULT_REG);
1251 		else if (GRAPHICS_VER_FULL(i915) >= IP_VER(12, 55))
1252 			ee->fault_reg = intel_gt_mcr_read_any(engine->gt,
1253 							      XEHP_RING_FAULT_REG);
1254 		else if (GRAPHICS_VER(i915) >= 12)
1255 			ee->fault_reg = intel_uncore_read(engine->uncore,
1256 							  GEN12_RING_FAULT_REG);
1257 		else if (GRAPHICS_VER(i915) >= 8)
1258 			ee->fault_reg = intel_uncore_read(engine->uncore,
1259 							  GEN8_RING_FAULT_REG);
1260 		else
1261 			ee->fault_reg = GEN6_RING_FAULT_REG_READ(engine);
1262 	}
1263 
1264 	if (GRAPHICS_VER(i915) >= 4) {
1265 		ee->esr = ENGINE_READ(engine, RING_ESR);
1266 		ee->faddr = ENGINE_READ(engine, RING_DMA_FADD);
1267 		ee->ipeir = ENGINE_READ(engine, RING_IPEIR);
1268 		ee->ipehr = ENGINE_READ(engine, RING_IPEHR);
1269 		ee->instps = ENGINE_READ(engine, RING_INSTPS);
1270 		ee->bbaddr = ENGINE_READ(engine, RING_BBADDR);
1271 		ee->ccid = ENGINE_READ(engine, CCID);
1272 		if (GRAPHICS_VER(i915) >= 8) {
1273 			ee->faddr |= (u64)ENGINE_READ(engine, RING_DMA_FADD_UDW) << 32;
1274 			ee->bbaddr |= (u64)ENGINE_READ(engine, RING_BBADDR_UDW) << 32;
1275 		}
1276 		ee->bbstate = ENGINE_READ(engine, RING_BBSTATE);
1277 	} else {
1278 		ee->faddr = ENGINE_READ(engine, DMA_FADD_I8XX);
1279 		ee->ipeir = ENGINE_READ(engine, IPEIR);
1280 		ee->ipehr = ENGINE_READ(engine, IPEHR);
1281 	}
1282 
1283 	if (GRAPHICS_VER(i915) >= 11) {
1284 		ee->cmd_cctl = ENGINE_READ(engine, RING_CMD_CCTL);
1285 		ee->cscmdop = ENGINE_READ(engine, RING_CSCMDOP);
1286 		ee->ctx_sr_ctl = ENGINE_READ(engine, RING_CTX_SR_CTL);
1287 		ee->dma_faddr_hi = ENGINE_READ(engine, RING_DMA_FADD_UDW);
1288 		ee->dma_faddr_lo = ENGINE_READ(engine, RING_DMA_FADD);
1289 		ee->nopid = ENGINE_READ(engine, RING_NOPID);
1290 		ee->excc = ENGINE_READ(engine, RING_EXCC);
1291 	}
1292 
1293 	intel_engine_get_instdone(engine, &ee->instdone);
1294 
1295 	ee->instpm = ENGINE_READ(engine, RING_INSTPM);
1296 	ee->acthd = intel_engine_get_active_head(engine);
1297 	ee->start = ENGINE_READ(engine, RING_START);
1298 	ee->head = ENGINE_READ(engine, RING_HEAD);
1299 	ee->tail = ENGINE_READ(engine, RING_TAIL);
1300 	ee->ctl = ENGINE_READ(engine, RING_CTL);
1301 	if (GRAPHICS_VER(i915) > 2)
1302 		ee->mode = ENGINE_READ(engine, RING_MI_MODE);
1303 
1304 	if (!HWS_NEEDS_PHYSICAL(i915)) {
1305 		i915_reg_t mmio;
1306 
1307 		if (GRAPHICS_VER(i915) == 7) {
1308 			switch (engine->id) {
1309 			default:
1310 				MISSING_CASE(engine->id);
1311 				fallthrough;
1312 			case RCS0:
1313 				mmio = RENDER_HWS_PGA_GEN7;
1314 				break;
1315 			case BCS0:
1316 				mmio = BLT_HWS_PGA_GEN7;
1317 				break;
1318 			case VCS0:
1319 				mmio = BSD_HWS_PGA_GEN7;
1320 				break;
1321 			case VECS0:
1322 				mmio = VEBOX_HWS_PGA_GEN7;
1323 				break;
1324 			}
1325 		} else if (GRAPHICS_VER(engine->i915) == 6) {
1326 			mmio = RING_HWS_PGA_GEN6(engine->mmio_base);
1327 		} else {
1328 			/* XXX: gen8 returns to sanity */
1329 			mmio = RING_HWS_PGA(engine->mmio_base);
1330 		}
1331 
1332 		ee->hws = intel_uncore_read(engine->uncore, mmio);
1333 	}
1334 
1335 	ee->reset_count = i915_reset_engine_count(&i915->gpu_error, engine);
1336 
1337 	if (HAS_PPGTT(i915)) {
1338 		int i;
1339 
1340 		ee->vm_info.gfx_mode = ENGINE_READ(engine, RING_MODE_GEN7);
1341 
1342 		if (GRAPHICS_VER(i915) == 6) {
1343 			ee->vm_info.pp_dir_base =
1344 				ENGINE_READ(engine, RING_PP_DIR_BASE_READ);
1345 		} else if (GRAPHICS_VER(i915) == 7) {
1346 			ee->vm_info.pp_dir_base =
1347 				ENGINE_READ(engine, RING_PP_DIR_BASE);
1348 		} else if (GRAPHICS_VER(i915) >= 8) {
1349 			u32 base = engine->mmio_base;
1350 
1351 			for (i = 0; i < 4; i++) {
1352 				ee->vm_info.pdp[i] =
1353 					intel_uncore_read(engine->uncore,
1354 							  GEN8_RING_PDP_UDW(base, i));
1355 				ee->vm_info.pdp[i] <<= 32;
1356 				ee->vm_info.pdp[i] |=
1357 					intel_uncore_read(engine->uncore,
1358 							  GEN8_RING_PDP_LDW(base, i));
1359 			}
1360 		}
1361 	}
1362 }
1363 
1364 static void record_request(const struct i915_request *request,
1365 			   struct i915_request_coredump *erq)
1366 {
1367 	erq->flags = request->fence.flags;
1368 	erq->context = request->fence.context;
1369 	erq->seqno = request->fence.seqno;
1370 	erq->sched_attr = request->sched.attr;
1371 	erq->head = request->head;
1372 	erq->tail = request->tail;
1373 
1374 	erq->pid = 0;
1375 	rcu_read_lock();
1376 	if (!intel_context_is_closed(request->context)) {
1377 		const struct i915_gem_context *ctx;
1378 
1379 		ctx = rcu_dereference(request->context->gem_context);
1380 		if (ctx)
1381 			erq->pid = pid_nr(ctx->pid);
1382 	}
1383 	rcu_read_unlock();
1384 }
1385 
1386 static void engine_record_execlists(struct intel_engine_coredump *ee)
1387 {
1388 	const struct intel_engine_execlists * const el = &ee->engine->execlists;
1389 	struct i915_request * const *port = el->active;
1390 	unsigned int n = 0;
1391 
1392 	while (*port)
1393 		record_request(*port++, &ee->execlist[n++]);
1394 
1395 	ee->num_ports = n;
1396 }
1397 
1398 static bool record_context(struct i915_gem_context_coredump *e,
1399 			   struct intel_context *ce)
1400 {
1401 	struct i915_gem_context *ctx;
1402 	struct task_struct *task;
1403 	bool simulated;
1404 
1405 	rcu_read_lock();
1406 	ctx = rcu_dereference(ce->gem_context);
1407 	if (ctx && !kref_get_unless_zero(&ctx->ref))
1408 		ctx = NULL;
1409 	rcu_read_unlock();
1410 	if (!ctx)
1411 		return true;
1412 
1413 	rcu_read_lock();
1414 	task = pid_task(ctx->pid, PIDTYPE_PID);
1415 	if (task) {
1416 		strcpy(e->comm, task->comm);
1417 		e->pid = task->pid;
1418 	}
1419 	rcu_read_unlock();
1420 
1421 	e->sched_attr = ctx->sched;
1422 	e->guilty = atomic_read(&ctx->guilty_count);
1423 	e->active = atomic_read(&ctx->active_count);
1424 	e->hwsp_seqno = (ce->timeline && ce->timeline->hwsp_seqno) ?
1425 				*ce->timeline->hwsp_seqno : ~0U;
1426 
1427 	e->total_runtime = intel_context_get_total_runtime_ns(ce);
1428 	e->avg_runtime = intel_context_get_avg_runtime_ns(ce);
1429 
1430 	simulated = i915_gem_context_no_error_capture(ctx);
1431 
1432 	i915_gem_context_put(ctx);
1433 	return simulated;
1434 }
1435 
1436 struct intel_engine_capture_vma {
1437 	struct intel_engine_capture_vma *next;
1438 	struct i915_vma_resource *vma_res;
1439 	char name[16];
1440 	bool lockdep_cookie;
1441 };
1442 
1443 static struct intel_engine_capture_vma *
1444 capture_vma_snapshot(struct intel_engine_capture_vma *next,
1445 		     struct i915_vma_resource *vma_res,
1446 		     gfp_t gfp, const char *name)
1447 {
1448 	struct intel_engine_capture_vma *c;
1449 
1450 	if (!vma_res)
1451 		return next;
1452 
1453 	c = kmalloc(sizeof(*c), gfp);
1454 	if (!c)
1455 		return next;
1456 
1457 	if (!i915_vma_resource_hold(vma_res, &c->lockdep_cookie)) {
1458 		kfree(c);
1459 		return next;
1460 	}
1461 
1462 	strcpy(c->name, name);
1463 	c->vma_res = i915_vma_resource_get(vma_res);
1464 
1465 	c->next = next;
1466 	return c;
1467 }
1468 
1469 static struct intel_engine_capture_vma *
1470 capture_vma(struct intel_engine_capture_vma *next,
1471 	    struct i915_vma *vma,
1472 	    const char *name,
1473 	    gfp_t gfp)
1474 {
1475 	if (!vma)
1476 		return next;
1477 
1478 	/*
1479 	 * If the vma isn't pinned, then the vma should be snapshotted
1480 	 * to a struct i915_vma_snapshot at command submission time.
1481 	 * Not here.
1482 	 */
1483 	if (GEM_WARN_ON(!i915_vma_is_pinned(vma)))
1484 		return next;
1485 
1486 	next = capture_vma_snapshot(next, vma->resource, gfp, name);
1487 
1488 	return next;
1489 }
1490 
1491 static struct intel_engine_capture_vma *
1492 capture_user(struct intel_engine_capture_vma *capture,
1493 	     const struct i915_request *rq,
1494 	     gfp_t gfp)
1495 {
1496 	struct i915_capture_list *c;
1497 
1498 	for (c = rq->capture_list; c; c = c->next)
1499 		capture = capture_vma_snapshot(capture, c->vma_res, gfp,
1500 					       "user");
1501 
1502 	return capture;
1503 }
1504 
1505 static void add_vma(struct intel_engine_coredump *ee,
1506 		    struct i915_vma_coredump *vma)
1507 {
1508 	if (vma) {
1509 		vma->next = ee->vma;
1510 		ee->vma = vma;
1511 	}
1512 }
1513 
1514 static struct i915_vma_coredump *
1515 create_vma_coredump(const struct intel_gt *gt, struct i915_vma *vma,
1516 		    const char *name, struct i915_vma_compress *compress)
1517 {
1518 	struct i915_vma_coredump *ret = NULL;
1519 	struct i915_vma_resource *vma_res;
1520 	bool lockdep_cookie;
1521 
1522 	if (!vma)
1523 		return NULL;
1524 
1525 	vma_res = vma->resource;
1526 
1527 	if (i915_vma_resource_hold(vma_res, &lockdep_cookie)) {
1528 		ret = i915_vma_coredump_create(gt, vma_res, compress, name);
1529 		i915_vma_resource_unhold(vma_res, lockdep_cookie);
1530 	}
1531 
1532 	return ret;
1533 }
1534 
1535 static void add_vma_coredump(struct intel_engine_coredump *ee,
1536 			     const struct intel_gt *gt,
1537 			     struct i915_vma *vma,
1538 			     const char *name,
1539 			     struct i915_vma_compress *compress)
1540 {
1541 	add_vma(ee, create_vma_coredump(gt, vma, name, compress));
1542 }
1543 
1544 struct intel_engine_coredump *
1545 intel_engine_coredump_alloc(struct intel_engine_cs *engine, gfp_t gfp, u32 dump_flags)
1546 {
1547 	struct intel_engine_coredump *ee;
1548 
1549 	ee = kzalloc(sizeof(*ee), gfp);
1550 	if (!ee)
1551 		return NULL;
1552 
1553 	ee->engine = engine;
1554 
1555 	if (!(dump_flags & CORE_DUMP_FLAG_IS_GUC_CAPTURE)) {
1556 		engine_record_registers(ee);
1557 		engine_record_execlists(ee);
1558 	}
1559 
1560 	return ee;
1561 }
1562 
1563 static struct intel_engine_capture_vma *
1564 engine_coredump_add_context(struct intel_engine_coredump *ee,
1565 			    struct intel_context *ce,
1566 			    gfp_t gfp)
1567 {
1568 	struct intel_engine_capture_vma *vma = NULL;
1569 
1570 	ee->simulated |= record_context(&ee->context, ce);
1571 	if (ee->simulated)
1572 		return NULL;
1573 
1574 	/*
1575 	 * We need to copy these to an anonymous buffer
1576 	 * as the simplest method to avoid being overwritten
1577 	 * by userspace.
1578 	 */
1579 	vma = capture_vma(vma, ce->ring->vma, "ring", gfp);
1580 	vma = capture_vma(vma, ce->state, "HW context", gfp);
1581 
1582 	return vma;
1583 }
1584 
1585 struct intel_engine_capture_vma *
1586 intel_engine_coredump_add_request(struct intel_engine_coredump *ee,
1587 				  struct i915_request *rq,
1588 				  gfp_t gfp)
1589 {
1590 	struct intel_engine_capture_vma *vma;
1591 
1592 	vma = engine_coredump_add_context(ee, rq->context, gfp);
1593 	if (!vma)
1594 		return NULL;
1595 
1596 	/*
1597 	 * We need to copy these to an anonymous buffer
1598 	 * as the simplest method to avoid being overwritten
1599 	 * by userspace.
1600 	 */
1601 	vma = capture_vma_snapshot(vma, rq->batch_res, gfp, "batch");
1602 	vma = capture_user(vma, rq, gfp);
1603 
1604 	ee->rq_head = rq->head;
1605 	ee->rq_post = rq->postfix;
1606 	ee->rq_tail = rq->tail;
1607 
1608 	return vma;
1609 }
1610 
1611 void
1612 intel_engine_coredump_add_vma(struct intel_engine_coredump *ee,
1613 			      struct intel_engine_capture_vma *capture,
1614 			      struct i915_vma_compress *compress)
1615 {
1616 	const struct intel_engine_cs *engine = ee->engine;
1617 
1618 	while (capture) {
1619 		struct intel_engine_capture_vma *this = capture;
1620 		struct i915_vma_resource *vma_res = this->vma_res;
1621 
1622 		add_vma(ee,
1623 			i915_vma_coredump_create(engine->gt, vma_res,
1624 						 compress, this->name));
1625 
1626 		i915_vma_resource_unhold(vma_res, this->lockdep_cookie);
1627 		i915_vma_resource_put(vma_res);
1628 
1629 		capture = this->next;
1630 		kfree(this);
1631 	}
1632 
1633 	add_vma_coredump(ee, engine->gt, engine->status_page.vma,
1634 			 "HW Status", compress);
1635 
1636 	add_vma_coredump(ee, engine->gt, engine->wa_ctx.vma,
1637 			 "WA context", compress);
1638 }
1639 
1640 static struct intel_engine_coredump *
1641 capture_engine(struct intel_engine_cs *engine,
1642 	       struct i915_vma_compress *compress,
1643 	       u32 dump_flags)
1644 {
1645 	struct intel_engine_capture_vma *capture = NULL;
1646 	struct intel_engine_coredump *ee;
1647 	struct intel_context *ce = NULL;
1648 	struct i915_request *rq = NULL;
1649 
1650 	ee = intel_engine_coredump_alloc(engine, ALLOW_FAIL, dump_flags);
1651 	if (!ee)
1652 		return NULL;
1653 
1654 	intel_engine_get_hung_entity(engine, &ce, &rq);
1655 	if (rq && !i915_request_started(rq))
1656 		drm_info(&engine->gt->i915->drm, "Got hung context on %s with active request %lld:%lld [0x%04X] not yet started\n",
1657 			 engine->name, rq->fence.context, rq->fence.seqno, ce->guc_id.id);
1658 
1659 	if (rq) {
1660 		capture = intel_engine_coredump_add_request(ee, rq, ATOMIC_MAYFAIL);
1661 		i915_request_put(rq);
1662 	} else if (ce) {
1663 		capture = engine_coredump_add_context(ee, ce, ATOMIC_MAYFAIL);
1664 	}
1665 
1666 	if (capture) {
1667 		intel_engine_coredump_add_vma(ee, capture, compress);
1668 
1669 		if (dump_flags & CORE_DUMP_FLAG_IS_GUC_CAPTURE)
1670 			intel_guc_capture_get_matching_node(engine->gt, ee, ce);
1671 	} else {
1672 		kfree(ee);
1673 		ee = NULL;
1674 	}
1675 
1676 	return ee;
1677 }
1678 
1679 static void
1680 gt_record_engines(struct intel_gt_coredump *gt,
1681 		  intel_engine_mask_t engine_mask,
1682 		  struct i915_vma_compress *compress,
1683 		  u32 dump_flags)
1684 {
1685 	struct intel_engine_cs *engine;
1686 	enum intel_engine_id id;
1687 
1688 	for_each_engine(engine, gt->_gt, id) {
1689 		struct intel_engine_coredump *ee;
1690 
1691 		/* Refill our page pool before entering atomic section */
1692 		pool_refill(&compress->pool, ALLOW_FAIL);
1693 
1694 		ee = capture_engine(engine, compress, dump_flags);
1695 		if (!ee)
1696 			continue;
1697 
1698 		ee->hung = engine->mask & engine_mask;
1699 
1700 		gt->simulated |= ee->simulated;
1701 		if (ee->simulated) {
1702 			if (dump_flags & CORE_DUMP_FLAG_IS_GUC_CAPTURE)
1703 				intel_guc_capture_free_node(ee);
1704 			kfree(ee);
1705 			continue;
1706 		}
1707 
1708 		ee->next = gt->engine;
1709 		gt->engine = ee;
1710 	}
1711 }
1712 
1713 static void gt_record_guc_ctb(struct intel_ctb_coredump *saved,
1714 			      const struct intel_guc_ct_buffer *ctb,
1715 			      const void *blob_ptr, struct intel_guc *guc)
1716 {
1717 	if (!ctb || !ctb->desc)
1718 		return;
1719 
1720 	saved->raw_status = ctb->desc->status;
1721 	saved->raw_head = ctb->desc->head;
1722 	saved->raw_tail = ctb->desc->tail;
1723 	saved->head = ctb->head;
1724 	saved->tail = ctb->tail;
1725 	saved->size = ctb->size;
1726 	saved->desc_offset = ((void *)ctb->desc) - blob_ptr;
1727 	saved->cmds_offset = ((void *)ctb->cmds) - blob_ptr;
1728 }
1729 
1730 static struct intel_uc_coredump *
1731 gt_record_uc(struct intel_gt_coredump *gt,
1732 	     struct i915_vma_compress *compress)
1733 {
1734 	const struct intel_uc *uc = &gt->_gt->uc;
1735 	struct intel_uc_coredump *error_uc;
1736 
1737 	error_uc = kzalloc(sizeof(*error_uc), ALLOW_FAIL);
1738 	if (!error_uc)
1739 		return NULL;
1740 
1741 	memcpy(&error_uc->guc_fw, &uc->guc.fw, sizeof(uc->guc.fw));
1742 	memcpy(&error_uc->huc_fw, &uc->huc.fw, sizeof(uc->huc.fw));
1743 
1744 	error_uc->guc_fw.file_selected.path = kstrdup(uc->guc.fw.file_selected.path, ALLOW_FAIL);
1745 	error_uc->huc_fw.file_selected.path = kstrdup(uc->huc.fw.file_selected.path, ALLOW_FAIL);
1746 	error_uc->guc_fw.file_wanted.path = kstrdup(uc->guc.fw.file_wanted.path, ALLOW_FAIL);
1747 	error_uc->huc_fw.file_wanted.path = kstrdup(uc->huc.fw.file_wanted.path, ALLOW_FAIL);
1748 
1749 	/*
1750 	 * Save the GuC log and include a timestamp reference for converting the
1751 	 * log times to system times (in conjunction with the error->boottime and
1752 	 * gt->clock_frequency fields saved elsewhere).
1753 	 */
1754 	error_uc->guc.timestamp = intel_uncore_read(gt->_gt->uncore, GUCPMTIMESTAMP);
1755 	error_uc->guc.vma_log = create_vma_coredump(gt->_gt, uc->guc.log.vma,
1756 						    "GuC log buffer", compress);
1757 	error_uc->guc.vma_ctb = create_vma_coredump(gt->_gt, uc->guc.ct.vma,
1758 						    "GuC CT buffer", compress);
1759 	error_uc->guc.last_fence = uc->guc.ct.requests.last_fence;
1760 	gt_record_guc_ctb(error_uc->guc.ctb + 0, &uc->guc.ct.ctbs.send,
1761 			  uc->guc.ct.ctbs.send.desc, (struct intel_guc *)&uc->guc);
1762 	gt_record_guc_ctb(error_uc->guc.ctb + 1, &uc->guc.ct.ctbs.recv,
1763 			  uc->guc.ct.ctbs.send.desc, (struct intel_guc *)&uc->guc);
1764 
1765 	return error_uc;
1766 }
1767 
1768 /* Capture display registers. */
1769 static void gt_record_display_regs(struct intel_gt_coredump *gt)
1770 {
1771 	struct intel_uncore *uncore = gt->_gt->uncore;
1772 	struct drm_i915_private *i915 = uncore->i915;
1773 
1774 	if (DISPLAY_VER(i915) >= 6 && DISPLAY_VER(i915) < 20)
1775 		gt->derrmr = intel_uncore_read(uncore, DERRMR);
1776 
1777 	if (GRAPHICS_VER(i915) >= 8)
1778 		gt->ier = intel_uncore_read(uncore, GEN8_DE_MISC_IER);
1779 	else if (IS_VALLEYVIEW(i915))
1780 		gt->ier = intel_uncore_read(uncore, VLV_IER);
1781 	else if (HAS_PCH_SPLIT(i915))
1782 		gt->ier = intel_uncore_read(uncore, DEIER);
1783 	else if (GRAPHICS_VER(i915) == 2)
1784 		gt->ier = intel_uncore_read16(uncore, GEN2_IER);
1785 	else
1786 		gt->ier = intel_uncore_read(uncore, GEN2_IER);
1787 }
1788 
1789 /* Capture all other registers that GuC doesn't capture. */
1790 static void gt_record_global_nonguc_regs(struct intel_gt_coredump *gt)
1791 {
1792 	struct intel_uncore *uncore = gt->_gt->uncore;
1793 	struct drm_i915_private *i915 = uncore->i915;
1794 	int i;
1795 
1796 	if (IS_VALLEYVIEW(i915)) {
1797 		gt->gtier[0] = intel_uncore_read(uncore, GTIER);
1798 		gt->ngtier = 1;
1799 	} else if (GRAPHICS_VER(i915) >= 11) {
1800 		gt->gtier[0] =
1801 			intel_uncore_read(uncore,
1802 					  GEN11_RENDER_COPY_INTR_ENABLE);
1803 		gt->gtier[1] =
1804 			intel_uncore_read(uncore, GEN11_VCS_VECS_INTR_ENABLE);
1805 		gt->gtier[2] =
1806 			intel_uncore_read(uncore, GEN11_GUC_SG_INTR_ENABLE);
1807 		gt->gtier[3] =
1808 			intel_uncore_read(uncore,
1809 					  GEN11_GPM_WGBOXPERF_INTR_ENABLE);
1810 		gt->gtier[4] =
1811 			intel_uncore_read(uncore,
1812 					  GEN11_CRYPTO_RSVD_INTR_ENABLE);
1813 		gt->gtier[5] =
1814 			intel_uncore_read(uncore,
1815 					  GEN11_GUNIT_CSME_INTR_ENABLE);
1816 		gt->ngtier = 6;
1817 	} else if (GRAPHICS_VER(i915) >= 8) {
1818 		for (i = 0; i < 4; i++)
1819 			gt->gtier[i] =
1820 				intel_uncore_read(uncore, GEN8_GT_IER(i));
1821 		gt->ngtier = 4;
1822 	} else if (HAS_PCH_SPLIT(i915)) {
1823 		gt->gtier[0] = intel_uncore_read(uncore, GTIER);
1824 		gt->ngtier = 1;
1825 	}
1826 
1827 	gt->eir = intel_uncore_read(uncore, EIR);
1828 	gt->pgtbl_er = intel_uncore_read(uncore, PGTBL_ER);
1829 }
1830 
1831 /*
1832  * Capture all registers that relate to workload submission.
1833  * NOTE: In GuC submission, when GuC resets an engine, it can dump these for us
1834  */
1835 static void gt_record_global_regs(struct intel_gt_coredump *gt)
1836 {
1837 	struct intel_uncore *uncore = gt->_gt->uncore;
1838 	struct drm_i915_private *i915 = uncore->i915;
1839 	int i;
1840 
1841 	/*
1842 	 * General organization
1843 	 * 1. Registers specific to a single generation
1844 	 * 2. Registers which belong to multiple generations
1845 	 * 3. Feature specific registers.
1846 	 * 4. Everything else
1847 	 * Please try to follow the order.
1848 	 */
1849 
1850 	/* 1: Registers specific to a single generation */
1851 	if (IS_VALLEYVIEW(i915))
1852 		gt->forcewake = intel_uncore_read_fw(uncore, FORCEWAKE_VLV);
1853 
1854 	if (GRAPHICS_VER(i915) == 7)
1855 		gt->err_int = intel_uncore_read(uncore, GEN7_ERR_INT);
1856 
1857 	if (GRAPHICS_VER_FULL(i915) >= IP_VER(12, 55)) {
1858 		gt->fault_data0 = intel_gt_mcr_read_any((struct intel_gt *)gt->_gt,
1859 							XEHP_FAULT_TLB_DATA0);
1860 		gt->fault_data1 = intel_gt_mcr_read_any((struct intel_gt *)gt->_gt,
1861 							XEHP_FAULT_TLB_DATA1);
1862 	} else if (GRAPHICS_VER(i915) >= 12) {
1863 		gt->fault_data0 = intel_uncore_read(uncore,
1864 						    GEN12_FAULT_TLB_DATA0);
1865 		gt->fault_data1 = intel_uncore_read(uncore,
1866 						    GEN12_FAULT_TLB_DATA1);
1867 	} else if (GRAPHICS_VER(i915) >= 8) {
1868 		gt->fault_data0 = intel_uncore_read(uncore,
1869 						    GEN8_FAULT_TLB_DATA0);
1870 		gt->fault_data1 = intel_uncore_read(uncore,
1871 						    GEN8_FAULT_TLB_DATA1);
1872 	}
1873 
1874 	if (GRAPHICS_VER(i915) == 6) {
1875 		gt->forcewake = intel_uncore_read_fw(uncore, FORCEWAKE);
1876 		gt->gab_ctl = intel_uncore_read(uncore, GAB_CTL);
1877 		gt->gfx_mode = intel_uncore_read(uncore, GFX_MODE);
1878 	}
1879 
1880 	/* 2: Registers which belong to multiple generations */
1881 	if (GRAPHICS_VER(i915) >= 7)
1882 		gt->forcewake = intel_uncore_read_fw(uncore, FORCEWAKE_MT);
1883 
1884 	if (GRAPHICS_VER(i915) >= 6) {
1885 		if (GRAPHICS_VER(i915) < 12) {
1886 			gt->error = intel_uncore_read(uncore, ERROR_GEN6);
1887 			gt->done_reg = intel_uncore_read(uncore, DONE_REG);
1888 		}
1889 	}
1890 
1891 	/* 3: Feature specific registers */
1892 	if (IS_GRAPHICS_VER(i915, 6, 7)) {
1893 		gt->gam_ecochk = intel_uncore_read(uncore, GAM_ECOCHK);
1894 		gt->gac_eco = intel_uncore_read(uncore, GAC_ECO_BITS);
1895 	}
1896 
1897 	if (IS_GRAPHICS_VER(i915, 8, 11))
1898 		gt->gtt_cache = intel_uncore_read(uncore, HSW_GTT_CACHE_EN);
1899 
1900 	if (GRAPHICS_VER(i915) == 12)
1901 		gt->aux_err = intel_uncore_read(uncore, GEN12_AUX_ERR_DBG);
1902 
1903 	if (GRAPHICS_VER(i915) >= 12) {
1904 		for (i = 0; i < I915_MAX_SFC; i++) {
1905 			/*
1906 			 * SFC_DONE resides in the VD forcewake domain, so it
1907 			 * only exists if the corresponding VCS engine is
1908 			 * present.
1909 			 */
1910 			if ((gt->_gt->info.sfc_mask & BIT(i)) == 0 ||
1911 			    !HAS_ENGINE(gt->_gt, _VCS(i * 2)))
1912 				continue;
1913 
1914 			gt->sfc_done[i] =
1915 				intel_uncore_read(uncore, GEN12_SFC_DONE(i));
1916 		}
1917 
1918 		gt->gam_done = intel_uncore_read(uncore, GEN12_GAM_DONE);
1919 	}
1920 }
1921 
1922 static void gt_record_info(struct intel_gt_coredump *gt)
1923 {
1924 	memcpy(&gt->info, &gt->_gt->info, sizeof(struct intel_gt_info));
1925 	gt->clock_frequency = gt->_gt->clock_frequency;
1926 	gt->clock_period_ns = gt->_gt->clock_period_ns;
1927 }
1928 
1929 /*
1930  * Generate a semi-unique error code. The code is not meant to have meaning, The
1931  * code's only purpose is to try to prevent false duplicated bug reports by
1932  * grossly estimating a GPU error state.
1933  *
1934  * TODO Ideally, hashing the batchbuffer would be a very nice way to determine
1935  * the hang if we could strip the GTT offset information from it.
1936  *
1937  * It's only a small step better than a random number in its current form.
1938  */
1939 static u32 generate_ecode(const struct intel_engine_coredump *ee)
1940 {
1941 	/*
1942 	 * IPEHR would be an ideal way to detect errors, as it's the gross
1943 	 * measure of "the command that hung." However, has some very common
1944 	 * synchronization commands which almost always appear in the case
1945 	 * strictly a client bug. Use instdone to differentiate those some.
1946 	 */
1947 	return ee ? ee->ipehr ^ ee->instdone.instdone : 0;
1948 }
1949 
1950 static const char *error_msg(struct i915_gpu_coredump *error)
1951 {
1952 	struct intel_engine_coredump *first = NULL;
1953 	unsigned int hung_classes = 0;
1954 	struct intel_gt_coredump *gt;
1955 	int len;
1956 
1957 	for (gt = error->gt; gt; gt = gt->next) {
1958 		struct intel_engine_coredump *cs;
1959 
1960 		for (cs = gt->engine; cs; cs = cs->next) {
1961 			if (cs->hung) {
1962 				hung_classes |= BIT(cs->engine->uabi_class);
1963 				if (!first)
1964 					first = cs;
1965 			}
1966 		}
1967 	}
1968 
1969 	len = scnprintf(error->error_msg, sizeof(error->error_msg),
1970 			"GPU HANG: ecode %d:%x:%08x",
1971 			GRAPHICS_VER(error->i915), hung_classes,
1972 			generate_ecode(first));
1973 	if (first && first->context.pid) {
1974 		/* Just show the first executing process, more is confusing */
1975 		len += scnprintf(error->error_msg + len,
1976 				 sizeof(error->error_msg) - len,
1977 				 ", in %s [%d]",
1978 				 first->context.comm, first->context.pid);
1979 	}
1980 
1981 	return error->error_msg;
1982 }
1983 
1984 static void capture_gen(struct i915_gpu_coredump *error)
1985 {
1986 	struct drm_i915_private *i915 = error->i915;
1987 
1988 	error->wakelock = atomic_read(&i915->runtime_pm.wakeref_count);
1989 	error->suspended = pm_runtime_suspended(i915->drm.dev);
1990 
1991 	error->iommu = i915_vtd_active(i915);
1992 	error->reset_count = i915_reset_count(&i915->gpu_error);
1993 	error->suspend_count = i915->suspend_count;
1994 
1995 	i915_params_copy(&error->params, &i915->params);
1996 	intel_display_params_copy(&error->display_params);
1997 	memcpy(&error->device_info,
1998 	       INTEL_INFO(i915),
1999 	       sizeof(error->device_info));
2000 	memcpy(&error->runtime_info,
2001 	       RUNTIME_INFO(i915),
2002 	       sizeof(error->runtime_info));
2003 	memcpy(&error->display_device_info, DISPLAY_INFO(i915),
2004 	       sizeof(error->display_device_info));
2005 	memcpy(&error->display_runtime_info, DISPLAY_RUNTIME_INFO(i915),
2006 	       sizeof(error->display_runtime_info));
2007 	error->driver_caps = i915->caps;
2008 }
2009 
2010 struct i915_gpu_coredump *
2011 i915_gpu_coredump_alloc(struct drm_i915_private *i915, gfp_t gfp)
2012 {
2013 	struct i915_gpu_coredump *error;
2014 
2015 	if (!i915->params.error_capture)
2016 		return NULL;
2017 
2018 	error = kzalloc(sizeof(*error), gfp);
2019 	if (!error)
2020 		return NULL;
2021 
2022 	kref_init(&error->ref);
2023 	error->i915 = i915;
2024 
2025 	error->time = ktime_get_real();
2026 	error->boottime = ktime_get_boottime();
2027 	error->uptime = ktime_sub(ktime_get(), to_gt(i915)->last_init_time);
2028 	error->capture = jiffies;
2029 
2030 	capture_gen(error);
2031 
2032 	return error;
2033 }
2034 
2035 #define DAY_AS_SECONDS(x) (24 * 60 * 60 * (x))
2036 
2037 struct intel_gt_coredump *
2038 intel_gt_coredump_alloc(struct intel_gt *gt, gfp_t gfp, u32 dump_flags)
2039 {
2040 	struct intel_gt_coredump *gc;
2041 
2042 	gc = kzalloc(sizeof(*gc), gfp);
2043 	if (!gc)
2044 		return NULL;
2045 
2046 	gc->_gt = gt;
2047 	gc->awake = intel_gt_pm_is_awake(gt);
2048 
2049 	gt_record_display_regs(gc);
2050 	gt_record_global_nonguc_regs(gc);
2051 
2052 	/*
2053 	 * GuC dumps global, eng-class and eng-instance registers
2054 	 * (that can change as part of engine state during execution)
2055 	 * before an engine is reset due to a hung context.
2056 	 * GuC captures and reports all three groups of registers
2057 	 * together as a single set before the engine is reset.
2058 	 * Thus, if GuC triggered the context reset we retrieve
2059 	 * the register values as part of gt_record_engines.
2060 	 */
2061 	if (!(dump_flags & CORE_DUMP_FLAG_IS_GUC_CAPTURE))
2062 		gt_record_global_regs(gc);
2063 
2064 	gt_record_fences(gc);
2065 
2066 	return gc;
2067 }
2068 
2069 struct i915_vma_compress *
2070 i915_vma_capture_prepare(struct intel_gt_coredump *gt)
2071 {
2072 	struct i915_vma_compress *compress;
2073 
2074 	compress = kmalloc(sizeof(*compress), ALLOW_FAIL);
2075 	if (!compress)
2076 		return NULL;
2077 
2078 	if (!compress_init(compress)) {
2079 		kfree(compress);
2080 		return NULL;
2081 	}
2082 
2083 	return compress;
2084 }
2085 
2086 void i915_vma_capture_finish(struct intel_gt_coredump *gt,
2087 			     struct i915_vma_compress *compress)
2088 {
2089 	if (!compress)
2090 		return;
2091 
2092 	compress_fini(compress);
2093 	kfree(compress);
2094 }
2095 
2096 static struct i915_gpu_coredump *
2097 __i915_gpu_coredump(struct intel_gt *gt, intel_engine_mask_t engine_mask, u32 dump_flags)
2098 {
2099 	struct drm_i915_private *i915 = gt->i915;
2100 	struct i915_gpu_coredump *error;
2101 
2102 	/* Check if GPU capture has been disabled */
2103 	error = READ_ONCE(i915->gpu_error.first_error);
2104 	if (IS_ERR(error))
2105 		return error;
2106 
2107 	error = i915_gpu_coredump_alloc(i915, ALLOW_FAIL);
2108 	if (!error)
2109 		return ERR_PTR(-ENOMEM);
2110 
2111 	error->gt = intel_gt_coredump_alloc(gt, ALLOW_FAIL, dump_flags);
2112 	if (error->gt) {
2113 		struct i915_vma_compress *compress;
2114 
2115 		compress = i915_vma_capture_prepare(error->gt);
2116 		if (!compress) {
2117 			kfree(error->gt);
2118 			kfree(error);
2119 			return ERR_PTR(-ENOMEM);
2120 		}
2121 
2122 		if (INTEL_INFO(i915)->has_gt_uc) {
2123 			error->gt->uc = gt_record_uc(error->gt, compress);
2124 			if (error->gt->uc) {
2125 				if (dump_flags & CORE_DUMP_FLAG_IS_GUC_CAPTURE)
2126 					error->gt->uc->guc.is_guc_capture = true;
2127 				else
2128 					GEM_BUG_ON(error->gt->uc->guc.is_guc_capture);
2129 			}
2130 		}
2131 
2132 		gt_record_info(error->gt);
2133 		gt_record_engines(error->gt, engine_mask, compress, dump_flags);
2134 
2135 
2136 		i915_vma_capture_finish(error->gt, compress);
2137 
2138 		error->simulated |= error->gt->simulated;
2139 	}
2140 
2141 	error->overlay = intel_overlay_capture_error_state(i915);
2142 
2143 	return error;
2144 }
2145 
2146 static struct i915_gpu_coredump *
2147 i915_gpu_coredump(struct intel_gt *gt, intel_engine_mask_t engine_mask, u32 dump_flags)
2148 {
2149 	static DEFINE_MUTEX(capture_mutex);
2150 	int ret = mutex_lock_interruptible(&capture_mutex);
2151 	struct i915_gpu_coredump *dump;
2152 
2153 	if (ret)
2154 		return ERR_PTR(ret);
2155 
2156 	dump = __i915_gpu_coredump(gt, engine_mask, dump_flags);
2157 	mutex_unlock(&capture_mutex);
2158 
2159 	return dump;
2160 }
2161 
2162 void i915_error_state_store(struct i915_gpu_coredump *error)
2163 {
2164 	struct drm_i915_private *i915;
2165 	static bool warned;
2166 
2167 	if (IS_ERR_OR_NULL(error))
2168 		return;
2169 
2170 	i915 = error->i915;
2171 	drm_info(&i915->drm, "%s\n", error_msg(error));
2172 
2173 	if (error->simulated ||
2174 	    cmpxchg(&i915->gpu_error.first_error, NULL, error))
2175 		return;
2176 
2177 	i915_gpu_coredump_get(error);
2178 
2179 	if (!xchg(&warned, true) &&
2180 	    ktime_get_real_seconds() - DRIVER_TIMESTAMP < DAY_AS_SECONDS(180)) {
2181 		pr_info("GPU hangs can indicate a bug anywhere in the entire gfx stack, including userspace.\n");
2182 		pr_info("Please file a _new_ bug report at https://gitlab.freedesktop.org/drm/intel/issues/new.\n");
2183 		pr_info("Please see https://drm.pages.freedesktop.org/intel-docs/how-to-file-i915-bugs.html for details.\n");
2184 		pr_info("drm/i915 developers can then reassign to the right component if it's not a kernel issue.\n");
2185 		pr_info("The GPU crash dump is required to analyze GPU hangs, so please always attach it.\n");
2186 		pr_info("GPU crash dump saved to /sys/class/drm/card%d/error\n",
2187 			i915->drm.primary->index);
2188 	}
2189 }
2190 
2191 /**
2192  * i915_capture_error_state - capture an error record for later analysis
2193  * @gt: intel_gt which originated the hang
2194  * @engine_mask: hung engines
2195  * @dump_flags: dump flags
2196  *
2197  * Should be called when an error is detected (either a hang or an error
2198  * interrupt) to capture error state from the time of the error.  Fills
2199  * out a structure which becomes available in debugfs for user level tools
2200  * to pick up.
2201  */
2202 void i915_capture_error_state(struct intel_gt *gt,
2203 			      intel_engine_mask_t engine_mask, u32 dump_flags)
2204 {
2205 	struct i915_gpu_coredump *error;
2206 
2207 	error = i915_gpu_coredump(gt, engine_mask, dump_flags);
2208 	if (IS_ERR(error)) {
2209 		cmpxchg(&gt->i915->gpu_error.first_error, NULL, error);
2210 		return;
2211 	}
2212 
2213 	i915_error_state_store(error);
2214 	i915_gpu_coredump_put(error);
2215 }
2216 
2217 static struct i915_gpu_coredump *
2218 i915_first_error_state(struct drm_i915_private *i915)
2219 {
2220 	struct i915_gpu_coredump *error;
2221 
2222 	spin_lock_irq(&i915->gpu_error.lock);
2223 	error = i915->gpu_error.first_error;
2224 	if (!IS_ERR_OR_NULL(error))
2225 		i915_gpu_coredump_get(error);
2226 	spin_unlock_irq(&i915->gpu_error.lock);
2227 
2228 	return error;
2229 }
2230 
2231 void i915_reset_error_state(struct drm_i915_private *i915)
2232 {
2233 	struct i915_gpu_coredump *error;
2234 
2235 	spin_lock_irq(&i915->gpu_error.lock);
2236 	error = i915->gpu_error.first_error;
2237 	if (error != ERR_PTR(-ENODEV)) /* if disabled, always disabled */
2238 		i915->gpu_error.first_error = NULL;
2239 	spin_unlock_irq(&i915->gpu_error.lock);
2240 
2241 	if (!IS_ERR_OR_NULL(error))
2242 		i915_gpu_coredump_put(error);
2243 }
2244 
2245 void i915_disable_error_state(struct drm_i915_private *i915, int err)
2246 {
2247 	spin_lock_irq(&i915->gpu_error.lock);
2248 	if (!i915->gpu_error.first_error)
2249 		i915->gpu_error.first_error = ERR_PTR(err);
2250 	spin_unlock_irq(&i915->gpu_error.lock);
2251 }
2252 
2253 #if IS_ENABLED(CONFIG_DRM_I915_DEBUG_GEM)
2254 void intel_klog_error_capture(struct intel_gt *gt,
2255 			      intel_engine_mask_t engine_mask)
2256 {
2257 	static int g_count;
2258 	struct drm_i915_private *i915 = gt->i915;
2259 	struct i915_gpu_coredump *error;
2260 	intel_wakeref_t wakeref;
2261 	size_t buf_size = PAGE_SIZE * 128;
2262 	size_t pos_err;
2263 	char *buf, *ptr, *next;
2264 	int l_count = g_count++;
2265 	int line = 0;
2266 
2267 	/* Can't allocate memory during a reset */
2268 	if (test_bit(I915_RESET_BACKOFF, &gt->reset.flags)) {
2269 		drm_err(&gt->i915->drm, "[Capture/%d.%d] Inside GT reset, skipping error capture :(\n",
2270 			l_count, line++);
2271 		return;
2272 	}
2273 
2274 	error = READ_ONCE(i915->gpu_error.first_error);
2275 	if (error) {
2276 		drm_err(&i915->drm, "[Capture/%d.%d] Clearing existing error capture first...\n",
2277 			l_count, line++);
2278 		i915_reset_error_state(i915);
2279 	}
2280 
2281 	with_intel_runtime_pm(&i915->runtime_pm, wakeref)
2282 		error = i915_gpu_coredump(gt, engine_mask, CORE_DUMP_FLAG_NONE);
2283 
2284 	if (IS_ERR(error)) {
2285 		drm_err(&i915->drm, "[Capture/%d.%d] Failed to capture error capture: %ld!\n",
2286 			l_count, line++, PTR_ERR(error));
2287 		return;
2288 	}
2289 
2290 	buf = kvmalloc(buf_size, GFP_KERNEL);
2291 	if (!buf) {
2292 		drm_err(&i915->drm, "[Capture/%d.%d] Failed to allocate buffer for error capture!\n",
2293 			l_count, line++);
2294 		i915_gpu_coredump_put(error);
2295 		return;
2296 	}
2297 
2298 	drm_info(&i915->drm, "[Capture/%d.%d] Dumping i915 error capture for %ps...\n",
2299 		 l_count, line++, __builtin_return_address(0));
2300 
2301 	/* Largest string length safe to print via dmesg */
2302 #	define MAX_CHUNK	800
2303 
2304 	pos_err = 0;
2305 	while (1) {
2306 		ssize_t got = i915_gpu_coredump_copy_to_buffer(error, buf, pos_err, buf_size - 1);
2307 
2308 		if (got <= 0)
2309 			break;
2310 
2311 		buf[got] = 0;
2312 		pos_err += got;
2313 
2314 		ptr = buf;
2315 		while (got > 0) {
2316 			size_t count;
2317 			char tag[2];
2318 
2319 			next = strnchr(ptr, got, '\n');
2320 			if (next) {
2321 				count = next - ptr;
2322 				*next = 0;
2323 				tag[0] = '>';
2324 				tag[1] = '<';
2325 			} else {
2326 				count = got;
2327 				tag[0] = '}';
2328 				tag[1] = '{';
2329 			}
2330 
2331 			if (count > MAX_CHUNK) {
2332 				size_t pos;
2333 				char *ptr2 = ptr;
2334 
2335 				for (pos = MAX_CHUNK; pos < count; pos += MAX_CHUNK) {
2336 					char chr = ptr[pos];
2337 
2338 					ptr[pos] = 0;
2339 					drm_info(&i915->drm, "[Capture/%d.%d] }%s{\n",
2340 						 l_count, line++, ptr2);
2341 					ptr[pos] = chr;
2342 					ptr2 = ptr + pos;
2343 
2344 					/*
2345 					 * If spewing large amounts of data via a serial console,
2346 					 * this can be a very slow process. So be friendly and try
2347 					 * not to cause 'softlockup on CPU' problems.
2348 					 */
2349 					cond_resched();
2350 				}
2351 
2352 				if (ptr2 < (ptr + count))
2353 					drm_info(&i915->drm, "[Capture/%d.%d] %c%s%c\n",
2354 						 l_count, line++, tag[0], ptr2, tag[1]);
2355 				else if (tag[0] == '>')
2356 					drm_info(&i915->drm, "[Capture/%d.%d] ><\n",
2357 						 l_count, line++);
2358 			} else {
2359 				drm_info(&i915->drm, "[Capture/%d.%d] %c%s%c\n",
2360 					 l_count, line++, tag[0], ptr, tag[1]);
2361 			}
2362 
2363 			ptr = next;
2364 			got -= count;
2365 			if (next) {
2366 				ptr++;
2367 				got--;
2368 			}
2369 
2370 			/* As above. */
2371 			cond_resched();
2372 		}
2373 
2374 		if (got)
2375 			drm_info(&i915->drm, "[Capture/%d.%d] Got %zd bytes remaining!\n",
2376 				 l_count, line++, got);
2377 	}
2378 
2379 	kvfree(buf);
2380 
2381 	drm_info(&i915->drm, "[Capture/%d.%d] Dumped %zd bytes\n", l_count, line++, pos_err);
2382 }
2383 #endif
2384 
2385 static ssize_t gpu_state_read(struct file *file, char __user *ubuf,
2386 			      size_t count, loff_t *pos)
2387 {
2388 	struct i915_gpu_coredump *error;
2389 	ssize_t ret;
2390 	void *buf;
2391 
2392 	error = file->private_data;
2393 	if (!error)
2394 		return 0;
2395 
2396 	/* Bounce buffer required because of kernfs __user API convenience. */
2397 	buf = kmalloc(count, GFP_KERNEL);
2398 	if (!buf)
2399 		return -ENOMEM;
2400 
2401 	ret = i915_gpu_coredump_copy_to_buffer(error, buf, *pos, count);
2402 	if (ret <= 0)
2403 		goto out;
2404 
2405 	if (!copy_to_user(ubuf, buf, ret))
2406 		*pos += ret;
2407 	else
2408 		ret = -EFAULT;
2409 
2410 out:
2411 	kfree(buf);
2412 	return ret;
2413 }
2414 
2415 static int gpu_state_release(struct inode *inode, struct file *file)
2416 {
2417 	i915_gpu_coredump_put(file->private_data);
2418 	return 0;
2419 }
2420 
2421 static int i915_gpu_info_open(struct inode *inode, struct file *file)
2422 {
2423 	struct drm_i915_private *i915 = inode->i_private;
2424 	struct i915_gpu_coredump *gpu;
2425 	intel_wakeref_t wakeref;
2426 
2427 	gpu = NULL;
2428 	with_intel_runtime_pm(&i915->runtime_pm, wakeref)
2429 		gpu = i915_gpu_coredump(to_gt(i915), ALL_ENGINES, CORE_DUMP_FLAG_NONE);
2430 
2431 	if (IS_ERR(gpu))
2432 		return PTR_ERR(gpu);
2433 
2434 	file->private_data = gpu;
2435 	return 0;
2436 }
2437 
2438 static const struct file_operations i915_gpu_info_fops = {
2439 	.owner = THIS_MODULE,
2440 	.open = i915_gpu_info_open,
2441 	.read = gpu_state_read,
2442 	.llseek = default_llseek,
2443 	.release = gpu_state_release,
2444 };
2445 
2446 static ssize_t
2447 i915_error_state_write(struct file *filp,
2448 		       const char __user *ubuf,
2449 		       size_t cnt,
2450 		       loff_t *ppos)
2451 {
2452 	struct i915_gpu_coredump *error = filp->private_data;
2453 
2454 	if (!error)
2455 		return 0;
2456 
2457 	drm_dbg(&error->i915->drm, "Resetting error state\n");
2458 	i915_reset_error_state(error->i915);
2459 
2460 	return cnt;
2461 }
2462 
2463 static int i915_error_state_open(struct inode *inode, struct file *file)
2464 {
2465 	struct i915_gpu_coredump *error;
2466 
2467 	error = i915_first_error_state(inode->i_private);
2468 	if (IS_ERR(error))
2469 		return PTR_ERR(error);
2470 
2471 	file->private_data  = error;
2472 	return 0;
2473 }
2474 
2475 static const struct file_operations i915_error_state_fops = {
2476 	.owner = THIS_MODULE,
2477 	.open = i915_error_state_open,
2478 	.read = gpu_state_read,
2479 	.write = i915_error_state_write,
2480 	.llseek = default_llseek,
2481 	.release = gpu_state_release,
2482 };
2483 
2484 void i915_gpu_error_debugfs_register(struct drm_i915_private *i915)
2485 {
2486 	struct drm_minor *minor = i915->drm.primary;
2487 
2488 	debugfs_create_file("i915_error_state", 0644, minor->debugfs_root, i915,
2489 			    &i915_error_state_fops);
2490 	debugfs_create_file("i915_gpu_info", 0644, minor->debugfs_root, i915,
2491 			    &i915_gpu_info_fops);
2492 }
2493 
2494 static ssize_t error_state_read(struct file *filp, struct kobject *kobj,
2495 				struct bin_attribute *attr, char *buf,
2496 				loff_t off, size_t count)
2497 {
2498 
2499 	struct device *kdev = kobj_to_dev(kobj);
2500 	struct drm_i915_private *i915 = kdev_minor_to_i915(kdev);
2501 	struct i915_gpu_coredump *gpu;
2502 	ssize_t ret = 0;
2503 
2504 	/*
2505 	 * FIXME: Concurrent clients triggering resets and reading + clearing
2506 	 * dumps can cause inconsistent sysfs reads when a user calls in with a
2507 	 * non-zero offset to complete a prior partial read but the
2508 	 * gpu_coredump has been cleared or replaced.
2509 	 */
2510 
2511 	gpu = i915_first_error_state(i915);
2512 	if (IS_ERR(gpu)) {
2513 		ret = PTR_ERR(gpu);
2514 	} else if (gpu) {
2515 		ret = i915_gpu_coredump_copy_to_buffer(gpu, buf, off, count);
2516 		i915_gpu_coredump_put(gpu);
2517 	} else {
2518 		const char *str = "No error state collected\n";
2519 		size_t len = strlen(str);
2520 
2521 		if (off < len) {
2522 			ret = min_t(size_t, count, len - off);
2523 			memcpy(buf, str + off, ret);
2524 		}
2525 	}
2526 
2527 	return ret;
2528 }
2529 
2530 static ssize_t error_state_write(struct file *file, struct kobject *kobj,
2531 				 struct bin_attribute *attr, char *buf,
2532 				 loff_t off, size_t count)
2533 {
2534 	struct device *kdev = kobj_to_dev(kobj);
2535 	struct drm_i915_private *dev_priv = kdev_minor_to_i915(kdev);
2536 
2537 	drm_dbg(&dev_priv->drm, "Resetting error state\n");
2538 	i915_reset_error_state(dev_priv);
2539 
2540 	return count;
2541 }
2542 
2543 static const struct bin_attribute error_state_attr = {
2544 	.attr.name = "error",
2545 	.attr.mode = S_IRUSR | S_IWUSR,
2546 	.size = 0,
2547 	.read = error_state_read,
2548 	.write = error_state_write,
2549 };
2550 
2551 void i915_gpu_error_sysfs_setup(struct drm_i915_private *i915)
2552 {
2553 	struct device *kdev = i915->drm.primary->kdev;
2554 
2555 	if (sysfs_create_bin_file(&kdev->kobj, &error_state_attr))
2556 		drm_err(&i915->drm, "error_state sysfs setup failed\n");
2557 }
2558 
2559 void i915_gpu_error_sysfs_teardown(struct drm_i915_private *i915)
2560 {
2561 	struct device *kdev = i915->drm.primary->kdev;
2562 
2563 	sysfs_remove_bin_file(&kdev->kobj, &error_state_attr);
2564 }
2565