1 // SPDX-License-Identifier: MIT
2 /*
3 * Copyright © 2008-2018 Intel Corporation
4 */
5
6 #include <linux/sched/mm.h>
7 #include <linux/stop_machine.h>
8 #include <linux/string_helpers.h>
9
10 #include "display/intel_display.h"
11 #include "display/intel_overlay.h"
12
13 #include "gem/i915_gem_context.h"
14
15 #include "gt/intel_gt_regs.h"
16
17 #include "i915_drv.h"
18 #include "i915_file_private.h"
19 #include "i915_gpu_error.h"
20 #include "i915_irq.h"
21 #include "intel_breadcrumbs.h"
22 #include "intel_engine_pm.h"
23 #include "intel_engine_regs.h"
24 #include "intel_gt.h"
25 #include "intel_gt_pm.h"
26 #include "intel_gt_requests.h"
27 #include "intel_mchbar_regs.h"
28 #include "intel_pci_config.h"
29 #include "intel_reset.h"
30
31 #include "uc/intel_guc.h"
32
33 #define RESET_MAX_RETRIES 3
34
35 /* XXX How to handle concurrent GGTT updates using tiling registers? */
36 #define RESET_UNDER_STOP_MACHINE 0
37
rmw_set_fw(struct intel_uncore * uncore,i915_reg_t reg,u32 set)38 static void rmw_set_fw(struct intel_uncore *uncore, i915_reg_t reg, u32 set)
39 {
40 intel_uncore_rmw_fw(uncore, reg, 0, set);
41 }
42
rmw_clear_fw(struct intel_uncore * uncore,i915_reg_t reg,u32 clr)43 static void rmw_clear_fw(struct intel_uncore *uncore, i915_reg_t reg, u32 clr)
44 {
45 intel_uncore_rmw_fw(uncore, reg, clr, 0);
46 }
47
client_mark_guilty(struct i915_gem_context * ctx,bool banned)48 static void client_mark_guilty(struct i915_gem_context *ctx, bool banned)
49 {
50 struct drm_i915_file_private *file_priv = ctx->file_priv;
51 unsigned long prev_hang;
52 unsigned int score;
53
54 if (IS_ERR_OR_NULL(file_priv))
55 return;
56
57 score = 0;
58 if (banned)
59 score = I915_CLIENT_SCORE_CONTEXT_BAN;
60
61 prev_hang = xchg(&file_priv->hang_timestamp, jiffies);
62 if (time_before(jiffies, prev_hang + I915_CLIENT_FAST_HANG_JIFFIES))
63 score += I915_CLIENT_SCORE_HANG_FAST;
64
65 if (score) {
66 atomic_add(score, &file_priv->ban_score);
67
68 drm_dbg(&ctx->i915->drm,
69 "client %s: gained %u ban score, now %u\n",
70 ctx->name, score,
71 atomic_read(&file_priv->ban_score));
72 }
73 }
74
mark_guilty(struct i915_request * rq)75 static bool mark_guilty(struct i915_request *rq)
76 {
77 struct i915_gem_context *ctx;
78 unsigned long prev_hang;
79 bool banned;
80 int i;
81
82 if (intel_context_is_closed(rq->context))
83 return true;
84
85 rcu_read_lock();
86 ctx = rcu_dereference(rq->context->gem_context);
87 if (ctx && !kref_get_unless_zero(&ctx->ref))
88 ctx = NULL;
89 rcu_read_unlock();
90 if (!ctx)
91 return intel_context_is_banned(rq->context);
92
93 atomic_inc(&ctx->guilty_count);
94
95 /* Cool contexts are too cool to be banned! (Used for reset testing.) */
96 if (!i915_gem_context_is_bannable(ctx)) {
97 banned = false;
98 goto out;
99 }
100
101 drm_notice(&ctx->i915->drm,
102 "%s context reset due to GPU hang\n",
103 ctx->name);
104
105 /* Record the timestamp for the last N hangs */
106 prev_hang = ctx->hang_timestamp[0];
107 for (i = 0; i < ARRAY_SIZE(ctx->hang_timestamp) - 1; i++)
108 ctx->hang_timestamp[i] = ctx->hang_timestamp[i + 1];
109 ctx->hang_timestamp[i] = jiffies;
110
111 /* If we have hung N+1 times in rapid succession, we ban the context! */
112 banned = !i915_gem_context_is_recoverable(ctx);
113 if (time_before(jiffies, prev_hang + CONTEXT_FAST_HANG_JIFFIES))
114 banned = true;
115 if (banned)
116 drm_dbg(&ctx->i915->drm, "context %s: guilty %d, banned\n",
117 ctx->name, atomic_read(&ctx->guilty_count));
118
119 client_mark_guilty(ctx, banned);
120
121 out:
122 i915_gem_context_put(ctx);
123 return banned;
124 }
125
mark_innocent(struct i915_request * rq)126 static void mark_innocent(struct i915_request *rq)
127 {
128 struct i915_gem_context *ctx;
129
130 rcu_read_lock();
131 ctx = rcu_dereference(rq->context->gem_context);
132 if (ctx)
133 atomic_inc(&ctx->active_count);
134 rcu_read_unlock();
135 }
136
__i915_request_reset(struct i915_request * rq,bool guilty)137 void __i915_request_reset(struct i915_request *rq, bool guilty)
138 {
139 bool banned = false;
140
141 RQ_TRACE(rq, "guilty? %s\n", str_yes_no(guilty));
142 GEM_BUG_ON(__i915_request_is_complete(rq));
143
144 rcu_read_lock(); /* protect the GEM context */
145 if (guilty) {
146 i915_request_set_error_once(rq, -EIO);
147 __i915_request_skip(rq);
148 banned = mark_guilty(rq);
149 } else {
150 i915_request_set_error_once(rq, -EAGAIN);
151 mark_innocent(rq);
152 }
153 rcu_read_unlock();
154
155 if (banned)
156 intel_context_ban(rq->context, rq);
157 }
158
i915_in_reset(struct pci_dev * pdev)159 static bool i915_in_reset(struct pci_dev *pdev)
160 {
161 u8 gdrst;
162
163 pci_read_config_byte(pdev, I915_GDRST, &gdrst);
164 return gdrst & GRDOM_RESET_STATUS;
165 }
166
i915_do_reset(struct intel_gt * gt,intel_engine_mask_t engine_mask,unsigned int retry)167 static int i915_do_reset(struct intel_gt *gt,
168 intel_engine_mask_t engine_mask,
169 unsigned int retry)
170 {
171 struct pci_dev *pdev = to_pci_dev(gt->i915->drm.dev);
172 int err;
173
174 /* Assert reset for at least 20 usec, and wait for acknowledgement. */
175 pci_write_config_byte(pdev, I915_GDRST, GRDOM_RESET_ENABLE);
176 udelay(50);
177 err = wait_for_atomic(i915_in_reset(pdev), 50);
178
179 /* Clear the reset request. */
180 pci_write_config_byte(pdev, I915_GDRST, 0);
181 udelay(50);
182 if (!err)
183 err = wait_for_atomic(!i915_in_reset(pdev), 50);
184
185 return err;
186 }
187
g4x_reset_complete(struct pci_dev * pdev)188 static bool g4x_reset_complete(struct pci_dev *pdev)
189 {
190 u8 gdrst;
191
192 pci_read_config_byte(pdev, I915_GDRST, &gdrst);
193 return (gdrst & GRDOM_RESET_ENABLE) == 0;
194 }
195
g33_do_reset(struct intel_gt * gt,intel_engine_mask_t engine_mask,unsigned int retry)196 static int g33_do_reset(struct intel_gt *gt,
197 intel_engine_mask_t engine_mask,
198 unsigned int retry)
199 {
200 struct pci_dev *pdev = to_pci_dev(gt->i915->drm.dev);
201
202 pci_write_config_byte(pdev, I915_GDRST, GRDOM_RESET_ENABLE);
203 return wait_for_atomic(g4x_reset_complete(pdev), 50);
204 }
205
g4x_do_reset(struct intel_gt * gt,intel_engine_mask_t engine_mask,unsigned int retry)206 static int g4x_do_reset(struct intel_gt *gt,
207 intel_engine_mask_t engine_mask,
208 unsigned int retry)
209 {
210 struct pci_dev *pdev = to_pci_dev(gt->i915->drm.dev);
211 struct intel_uncore *uncore = gt->uncore;
212 int ret;
213
214 /* WaVcpClkGateDisableForMediaReset:ctg,elk */
215 rmw_set_fw(uncore, VDECCLK_GATE_D, VCP_UNIT_CLOCK_GATE_DISABLE);
216 intel_uncore_posting_read_fw(uncore, VDECCLK_GATE_D);
217
218 pci_write_config_byte(pdev, I915_GDRST,
219 GRDOM_MEDIA | GRDOM_RESET_ENABLE);
220 ret = wait_for_atomic(g4x_reset_complete(pdev), 50);
221 if (ret) {
222 GT_TRACE(gt, "Wait for media reset failed\n");
223 goto out;
224 }
225
226 pci_write_config_byte(pdev, I915_GDRST,
227 GRDOM_RENDER | GRDOM_RESET_ENABLE);
228 ret = wait_for_atomic(g4x_reset_complete(pdev), 50);
229 if (ret) {
230 GT_TRACE(gt, "Wait for render reset failed\n");
231 goto out;
232 }
233
234 out:
235 pci_write_config_byte(pdev, I915_GDRST, 0);
236
237 rmw_clear_fw(uncore, VDECCLK_GATE_D, VCP_UNIT_CLOCK_GATE_DISABLE);
238 intel_uncore_posting_read_fw(uncore, VDECCLK_GATE_D);
239
240 return ret;
241 }
242
ilk_do_reset(struct intel_gt * gt,intel_engine_mask_t engine_mask,unsigned int retry)243 static int ilk_do_reset(struct intel_gt *gt, intel_engine_mask_t engine_mask,
244 unsigned int retry)
245 {
246 struct intel_uncore *uncore = gt->uncore;
247 int ret;
248
249 intel_uncore_write_fw(uncore, ILK_GDSR,
250 ILK_GRDOM_RENDER | ILK_GRDOM_RESET_ENABLE);
251 ret = __intel_wait_for_register_fw(uncore, ILK_GDSR,
252 ILK_GRDOM_RESET_ENABLE, 0,
253 5000, 0,
254 NULL);
255 if (ret) {
256 GT_TRACE(gt, "Wait for render reset failed\n");
257 goto out;
258 }
259
260 intel_uncore_write_fw(uncore, ILK_GDSR,
261 ILK_GRDOM_MEDIA | ILK_GRDOM_RESET_ENABLE);
262 ret = __intel_wait_for_register_fw(uncore, ILK_GDSR,
263 ILK_GRDOM_RESET_ENABLE, 0,
264 5000, 0,
265 NULL);
266 if (ret) {
267 GT_TRACE(gt, "Wait for media reset failed\n");
268 goto out;
269 }
270
271 out:
272 intel_uncore_write_fw(uncore, ILK_GDSR, 0);
273 intel_uncore_posting_read_fw(uncore, ILK_GDSR);
274 return ret;
275 }
276
277 /* Reset the hardware domains (GENX_GRDOM_*) specified by mask */
gen6_hw_domain_reset(struct intel_gt * gt,u32 hw_domain_mask)278 static int gen6_hw_domain_reset(struct intel_gt *gt, u32 hw_domain_mask)
279 {
280 struct intel_uncore *uncore = gt->uncore;
281 int err;
282
283 /*
284 * GEN6_GDRST is not in the gt power well, no need to check
285 * for fifo space for the write or forcewake the chip for
286 * the read
287 */
288 intel_uncore_write_fw(uncore, GEN6_GDRST, hw_domain_mask);
289
290 /* Wait for the device to ack the reset requests */
291 err = __intel_wait_for_register_fw(uncore,
292 GEN6_GDRST, hw_domain_mask, 0,
293 500, 0,
294 NULL);
295 if (err)
296 GT_TRACE(gt,
297 "Wait for 0x%08x engines reset failed\n",
298 hw_domain_mask);
299
300 return err;
301 }
302
__gen6_reset_engines(struct intel_gt * gt,intel_engine_mask_t engine_mask,unsigned int retry)303 static int __gen6_reset_engines(struct intel_gt *gt,
304 intel_engine_mask_t engine_mask,
305 unsigned int retry)
306 {
307 struct intel_engine_cs *engine;
308 u32 hw_mask;
309
310 if (engine_mask == ALL_ENGINES) {
311 hw_mask = GEN6_GRDOM_FULL;
312 } else {
313 intel_engine_mask_t tmp;
314
315 hw_mask = 0;
316 for_each_engine_masked(engine, gt, engine_mask, tmp) {
317 hw_mask |= engine->reset_domain;
318 }
319 }
320
321 return gen6_hw_domain_reset(gt, hw_mask);
322 }
323
gen6_reset_engines(struct intel_gt * gt,intel_engine_mask_t engine_mask,unsigned int retry)324 static int gen6_reset_engines(struct intel_gt *gt,
325 intel_engine_mask_t engine_mask,
326 unsigned int retry)
327 {
328 unsigned long flags;
329 int ret;
330
331 spin_lock_irqsave(>->uncore->lock, flags);
332 ret = __gen6_reset_engines(gt, engine_mask, retry);
333 spin_unlock_irqrestore(>->uncore->lock, flags);
334
335 return ret;
336 }
337
find_sfc_paired_vecs_engine(struct intel_engine_cs * engine)338 static struct intel_engine_cs *find_sfc_paired_vecs_engine(struct intel_engine_cs *engine)
339 {
340 int vecs_id;
341
342 GEM_BUG_ON(engine->class != VIDEO_DECODE_CLASS);
343
344 vecs_id = _VECS((engine->instance) / 2);
345
346 return engine->gt->engine[vecs_id];
347 }
348
349 struct sfc_lock_data {
350 i915_reg_t lock_reg;
351 i915_reg_t ack_reg;
352 i915_reg_t usage_reg;
353 u32 lock_bit;
354 u32 ack_bit;
355 u32 usage_bit;
356 u32 reset_bit;
357 };
358
get_sfc_forced_lock_data(struct intel_engine_cs * engine,struct sfc_lock_data * sfc_lock)359 static void get_sfc_forced_lock_data(struct intel_engine_cs *engine,
360 struct sfc_lock_data *sfc_lock)
361 {
362 switch (engine->class) {
363 default:
364 MISSING_CASE(engine->class);
365 fallthrough;
366 case VIDEO_DECODE_CLASS:
367 sfc_lock->lock_reg = GEN11_VCS_SFC_FORCED_LOCK(engine->mmio_base);
368 sfc_lock->lock_bit = GEN11_VCS_SFC_FORCED_LOCK_BIT;
369
370 sfc_lock->ack_reg = GEN11_VCS_SFC_LOCK_STATUS(engine->mmio_base);
371 sfc_lock->ack_bit = GEN11_VCS_SFC_LOCK_ACK_BIT;
372
373 sfc_lock->usage_reg = GEN11_VCS_SFC_LOCK_STATUS(engine->mmio_base);
374 sfc_lock->usage_bit = GEN11_VCS_SFC_USAGE_BIT;
375 sfc_lock->reset_bit = GEN11_VCS_SFC_RESET_BIT(engine->instance);
376
377 break;
378 case VIDEO_ENHANCEMENT_CLASS:
379 sfc_lock->lock_reg = GEN11_VECS_SFC_FORCED_LOCK(engine->mmio_base);
380 sfc_lock->lock_bit = GEN11_VECS_SFC_FORCED_LOCK_BIT;
381
382 sfc_lock->ack_reg = GEN11_VECS_SFC_LOCK_ACK(engine->mmio_base);
383 sfc_lock->ack_bit = GEN11_VECS_SFC_LOCK_ACK_BIT;
384
385 sfc_lock->usage_reg = GEN11_VECS_SFC_USAGE(engine->mmio_base);
386 sfc_lock->usage_bit = GEN11_VECS_SFC_USAGE_BIT;
387 sfc_lock->reset_bit = GEN11_VECS_SFC_RESET_BIT(engine->instance);
388
389 break;
390 }
391 }
392
gen11_lock_sfc(struct intel_engine_cs * engine,u32 * reset_mask,u32 * unlock_mask)393 static int gen11_lock_sfc(struct intel_engine_cs *engine,
394 u32 *reset_mask,
395 u32 *unlock_mask)
396 {
397 struct intel_uncore *uncore = engine->uncore;
398 u8 vdbox_sfc_access = engine->gt->info.vdbox_sfc_access;
399 struct sfc_lock_data sfc_lock;
400 bool lock_obtained, lock_to_other = false;
401 int ret;
402
403 switch (engine->class) {
404 case VIDEO_DECODE_CLASS:
405 if ((BIT(engine->instance) & vdbox_sfc_access) == 0)
406 return 0;
407
408 fallthrough;
409 case VIDEO_ENHANCEMENT_CLASS:
410 get_sfc_forced_lock_data(engine, &sfc_lock);
411
412 break;
413 default:
414 return 0;
415 }
416
417 if (!(intel_uncore_read_fw(uncore, sfc_lock.usage_reg) & sfc_lock.usage_bit)) {
418 struct intel_engine_cs *paired_vecs;
419
420 if (engine->class != VIDEO_DECODE_CLASS ||
421 GRAPHICS_VER(engine->i915) != 12)
422 return 0;
423
424 /*
425 * Wa_14010733141
426 *
427 * If the VCS-MFX isn't using the SFC, we also need to check
428 * whether VCS-HCP is using it. If so, we need to issue a *VE*
429 * forced lock on the VE engine that shares the same SFC.
430 */
431 if (!(intel_uncore_read_fw(uncore,
432 GEN12_HCP_SFC_LOCK_STATUS(engine->mmio_base)) &
433 GEN12_HCP_SFC_USAGE_BIT))
434 return 0;
435
436 paired_vecs = find_sfc_paired_vecs_engine(engine);
437 get_sfc_forced_lock_data(paired_vecs, &sfc_lock);
438 lock_to_other = true;
439 *unlock_mask |= paired_vecs->mask;
440 } else {
441 *unlock_mask |= engine->mask;
442 }
443
444 /*
445 * If the engine is using an SFC, tell the engine that a software reset
446 * is going to happen. The engine will then try to force lock the SFC.
447 * If SFC ends up being locked to the engine we want to reset, we have
448 * to reset it as well (we will unlock it once the reset sequence is
449 * completed).
450 */
451 rmw_set_fw(uncore, sfc_lock.lock_reg, sfc_lock.lock_bit);
452
453 ret = __intel_wait_for_register_fw(uncore,
454 sfc_lock.ack_reg,
455 sfc_lock.ack_bit,
456 sfc_lock.ack_bit,
457 1000, 0, NULL);
458
459 /*
460 * Was the SFC released while we were trying to lock it?
461 *
462 * We should reset both the engine and the SFC if:
463 * - We were locking the SFC to this engine and the lock succeeded
464 * OR
465 * - We were locking the SFC to a different engine (Wa_14010733141)
466 * but the SFC was released before the lock was obtained.
467 *
468 * Otherwise we need only reset the engine by itself and we can
469 * leave the SFC alone.
470 */
471 lock_obtained = (intel_uncore_read_fw(uncore, sfc_lock.usage_reg) &
472 sfc_lock.usage_bit) != 0;
473 if (lock_obtained == lock_to_other)
474 return 0;
475
476 if (ret) {
477 ENGINE_TRACE(engine, "Wait for SFC forced lock ack failed\n");
478 return ret;
479 }
480
481 *reset_mask |= sfc_lock.reset_bit;
482 return 0;
483 }
484
gen11_unlock_sfc(struct intel_engine_cs * engine)485 static void gen11_unlock_sfc(struct intel_engine_cs *engine)
486 {
487 struct intel_uncore *uncore = engine->uncore;
488 u8 vdbox_sfc_access = engine->gt->info.vdbox_sfc_access;
489 struct sfc_lock_data sfc_lock = {};
490
491 if (engine->class != VIDEO_DECODE_CLASS &&
492 engine->class != VIDEO_ENHANCEMENT_CLASS)
493 return;
494
495 if (engine->class == VIDEO_DECODE_CLASS &&
496 (BIT(engine->instance) & vdbox_sfc_access) == 0)
497 return;
498
499 get_sfc_forced_lock_data(engine, &sfc_lock);
500
501 rmw_clear_fw(uncore, sfc_lock.lock_reg, sfc_lock.lock_bit);
502 }
503
__gen11_reset_engines(struct intel_gt * gt,intel_engine_mask_t engine_mask,unsigned int retry)504 static int __gen11_reset_engines(struct intel_gt *gt,
505 intel_engine_mask_t engine_mask,
506 unsigned int retry)
507 {
508 struct intel_engine_cs *engine;
509 intel_engine_mask_t tmp;
510 u32 reset_mask, unlock_mask = 0;
511 int ret;
512
513 if (engine_mask == ALL_ENGINES) {
514 reset_mask = GEN11_GRDOM_FULL;
515 } else {
516 reset_mask = 0;
517 for_each_engine_masked(engine, gt, engine_mask, tmp) {
518 reset_mask |= engine->reset_domain;
519 ret = gen11_lock_sfc(engine, &reset_mask, &unlock_mask);
520 if (ret)
521 goto sfc_unlock;
522 }
523 }
524
525 ret = gen6_hw_domain_reset(gt, reset_mask);
526
527 sfc_unlock:
528 /*
529 * We unlock the SFC based on the lock status and not the result of
530 * gen11_lock_sfc to make sure that we clean properly if something
531 * wrong happened during the lock (e.g. lock acquired after timeout
532 * expiration).
533 *
534 * Due to Wa_14010733141, we may have locked an SFC to an engine that
535 * wasn't being reset. So instead of calling gen11_unlock_sfc()
536 * on engine_mask, we instead call it on the mask of engines that our
537 * gen11_lock_sfc() calls told us actually had locks attempted.
538 */
539 for_each_engine_masked(engine, gt, unlock_mask, tmp)
540 gen11_unlock_sfc(engine);
541
542 return ret;
543 }
544
gen8_engine_reset_prepare(struct intel_engine_cs * engine)545 static int gen8_engine_reset_prepare(struct intel_engine_cs *engine)
546 {
547 struct intel_uncore *uncore = engine->uncore;
548 const i915_reg_t reg = RING_RESET_CTL(engine->mmio_base);
549 u32 request, mask, ack;
550 int ret;
551
552 if (I915_SELFTEST_ONLY(should_fail(&engine->reset_timeout, 1)))
553 return -ETIMEDOUT;
554
555 ack = intel_uncore_read_fw(uncore, reg);
556 if (ack & RESET_CTL_CAT_ERROR) {
557 /*
558 * For catastrophic errors, ready-for-reset sequence
559 * needs to be bypassed: HAS#396813
560 */
561 request = RESET_CTL_CAT_ERROR;
562 mask = RESET_CTL_CAT_ERROR;
563
564 /* Catastrophic errors need to be cleared by HW */
565 ack = 0;
566 } else if (!(ack & RESET_CTL_READY_TO_RESET)) {
567 request = RESET_CTL_REQUEST_RESET;
568 mask = RESET_CTL_READY_TO_RESET;
569 ack = RESET_CTL_READY_TO_RESET;
570 } else {
571 return 0;
572 }
573
574 intel_uncore_write_fw(uncore, reg, _MASKED_BIT_ENABLE(request));
575 ret = __intel_wait_for_register_fw(uncore, reg, mask, ack,
576 700, 0, NULL);
577 if (ret)
578 drm_err(&engine->i915->drm,
579 "%s reset request timed out: {request: %08x, RESET_CTL: %08x}\n",
580 engine->name, request,
581 intel_uncore_read_fw(uncore, reg));
582
583 return ret;
584 }
585
gen8_engine_reset_cancel(struct intel_engine_cs * engine)586 static void gen8_engine_reset_cancel(struct intel_engine_cs *engine)
587 {
588 intel_uncore_write_fw(engine->uncore,
589 RING_RESET_CTL(engine->mmio_base),
590 _MASKED_BIT_DISABLE(RESET_CTL_REQUEST_RESET));
591 }
592
gen8_reset_engines(struct intel_gt * gt,intel_engine_mask_t engine_mask,unsigned int retry)593 static int gen8_reset_engines(struct intel_gt *gt,
594 intel_engine_mask_t engine_mask,
595 unsigned int retry)
596 {
597 struct intel_engine_cs *engine;
598 const bool reset_non_ready = retry >= 1;
599 intel_engine_mask_t tmp;
600 unsigned long flags;
601 int ret;
602
603 spin_lock_irqsave(>->uncore->lock, flags);
604
605 for_each_engine_masked(engine, gt, engine_mask, tmp) {
606 ret = gen8_engine_reset_prepare(engine);
607 if (ret && !reset_non_ready)
608 goto skip_reset;
609
610 /*
611 * If this is not the first failed attempt to prepare,
612 * we decide to proceed anyway.
613 *
614 * By doing so we risk context corruption and with
615 * some gens (kbl), possible system hang if reset
616 * happens during active bb execution.
617 *
618 * We rather take context corruption instead of
619 * failed reset with a wedged driver/gpu. And
620 * active bb execution case should be covered by
621 * stop_engines() we have before the reset.
622 */
623 }
624
625 /*
626 * Wa_22011100796:dg2, whenever Full soft reset is required,
627 * reset all individual engines firstly, and then do a full soft reset.
628 *
629 * This is best effort, so ignore any error from the initial reset.
630 */
631 if (IS_DG2(gt->i915) && engine_mask == ALL_ENGINES)
632 __gen11_reset_engines(gt, gt->info.engine_mask, 0);
633
634 if (GRAPHICS_VER(gt->i915) >= 11)
635 ret = __gen11_reset_engines(gt, engine_mask, retry);
636 else
637 ret = __gen6_reset_engines(gt, engine_mask, retry);
638
639 skip_reset:
640 for_each_engine_masked(engine, gt, engine_mask, tmp)
641 gen8_engine_reset_cancel(engine);
642
643 spin_unlock_irqrestore(>->uncore->lock, flags);
644
645 return ret;
646 }
647
mock_reset(struct intel_gt * gt,intel_engine_mask_t mask,unsigned int retry)648 static int mock_reset(struct intel_gt *gt,
649 intel_engine_mask_t mask,
650 unsigned int retry)
651 {
652 return 0;
653 }
654
655 typedef int (*reset_func)(struct intel_gt *,
656 intel_engine_mask_t engine_mask,
657 unsigned int retry);
658
intel_get_gpu_reset(const struct intel_gt * gt)659 static reset_func intel_get_gpu_reset(const struct intel_gt *gt)
660 {
661 struct drm_i915_private *i915 = gt->i915;
662
663 if (is_mock_gt(gt))
664 return mock_reset;
665 else if (GRAPHICS_VER(i915) >= 8)
666 return gen8_reset_engines;
667 else if (GRAPHICS_VER(i915) >= 6)
668 return gen6_reset_engines;
669 else if (GRAPHICS_VER(i915) >= 5)
670 return ilk_do_reset;
671 else if (IS_G4X(i915))
672 return g4x_do_reset;
673 else if (IS_G33(i915) || IS_PINEVIEW(i915))
674 return g33_do_reset;
675 else if (GRAPHICS_VER(i915) >= 3)
676 return i915_do_reset;
677 else
678 return NULL;
679 }
680
__intel_gt_reset(struct intel_gt * gt,intel_engine_mask_t engine_mask)681 int __intel_gt_reset(struct intel_gt *gt, intel_engine_mask_t engine_mask)
682 {
683 const int retries = engine_mask == ALL_ENGINES ? RESET_MAX_RETRIES : 1;
684 reset_func reset;
685 int ret = -ETIMEDOUT;
686 int retry;
687
688 reset = intel_get_gpu_reset(gt);
689 if (!reset)
690 return -ENODEV;
691
692 /*
693 * If the power well sleeps during the reset, the reset
694 * request may be dropped and never completes (causing -EIO).
695 */
696 intel_uncore_forcewake_get(gt->uncore, FORCEWAKE_ALL);
697 for (retry = 0; ret == -ETIMEDOUT && retry < retries; retry++) {
698 GT_TRACE(gt, "engine_mask=%x\n", engine_mask);
699 preempt_disable();
700 ret = reset(gt, engine_mask, retry);
701 preempt_enable();
702 }
703 intel_uncore_forcewake_put(gt->uncore, FORCEWAKE_ALL);
704
705 return ret;
706 }
707
intel_has_gpu_reset(const struct intel_gt * gt)708 bool intel_has_gpu_reset(const struct intel_gt *gt)
709 {
710 if (!gt->i915->params.reset)
711 return NULL;
712
713 return intel_get_gpu_reset(gt);
714 }
715
intel_has_reset_engine(const struct intel_gt * gt)716 bool intel_has_reset_engine(const struct intel_gt *gt)
717 {
718 if (gt->i915->params.reset < 2)
719 return false;
720
721 return INTEL_INFO(gt->i915)->has_reset_engine;
722 }
723
intel_reset_guc(struct intel_gt * gt)724 int intel_reset_guc(struct intel_gt *gt)
725 {
726 u32 guc_domain =
727 GRAPHICS_VER(gt->i915) >= 11 ? GEN11_GRDOM_GUC : GEN9_GRDOM_GUC;
728 int ret;
729
730 GEM_BUG_ON(!HAS_GT_UC(gt->i915));
731
732 intel_uncore_forcewake_get(gt->uncore, FORCEWAKE_ALL);
733 ret = gen6_hw_domain_reset(gt, guc_domain);
734 intel_uncore_forcewake_put(gt->uncore, FORCEWAKE_ALL);
735
736 return ret;
737 }
738
739 /*
740 * Ensure irq handler finishes, and not run again.
741 * Also return the active request so that we only search for it once.
742 */
reset_prepare_engine(struct intel_engine_cs * engine)743 static void reset_prepare_engine(struct intel_engine_cs *engine)
744 {
745 /*
746 * During the reset sequence, we must prevent the engine from
747 * entering RC6. As the context state is undefined until we restart
748 * the engine, if it does enter RC6 during the reset, the state
749 * written to the powercontext is undefined and so we may lose
750 * GPU state upon resume, i.e. fail to restart after a reset.
751 */
752 intel_uncore_forcewake_get(engine->uncore, FORCEWAKE_ALL);
753 if (engine->reset.prepare)
754 engine->reset.prepare(engine);
755 }
756
revoke_mmaps(struct intel_gt * gt)757 static void revoke_mmaps(struct intel_gt *gt)
758 {
759 int i;
760
761 for (i = 0; i < gt->ggtt->num_fences; i++) {
762 struct drm_vma_offset_node *node;
763 struct i915_vma *vma;
764 u64 vma_offset;
765
766 vma = READ_ONCE(gt->ggtt->fence_regs[i].vma);
767 if (!vma)
768 continue;
769
770 if (!i915_vma_has_userfault(vma))
771 continue;
772
773 GEM_BUG_ON(vma->fence != >->ggtt->fence_regs[i]);
774
775 if (!vma->mmo)
776 continue;
777
778 node = &vma->mmo->vma_node;
779 vma_offset = vma->ggtt_view.partial.offset << PAGE_SHIFT;
780
781 unmap_mapping_range(gt->i915->drm.anon_inode->i_mapping,
782 drm_vma_node_offset_addr(node) + vma_offset,
783 vma->size,
784 1);
785 }
786 }
787
reset_prepare(struct intel_gt * gt)788 static intel_engine_mask_t reset_prepare(struct intel_gt *gt)
789 {
790 struct intel_engine_cs *engine;
791 intel_engine_mask_t awake = 0;
792 enum intel_engine_id id;
793
794 /* For GuC mode, ensure submission is disabled before stopping ring */
795 intel_uc_reset_prepare(>->uc);
796
797 for_each_engine(engine, gt, id) {
798 if (intel_engine_pm_get_if_awake(engine))
799 awake |= engine->mask;
800 reset_prepare_engine(engine);
801 }
802
803 return awake;
804 }
805
gt_revoke(struct intel_gt * gt)806 static void gt_revoke(struct intel_gt *gt)
807 {
808 revoke_mmaps(gt);
809 }
810
gt_reset(struct intel_gt * gt,intel_engine_mask_t stalled_mask)811 static int gt_reset(struct intel_gt *gt, intel_engine_mask_t stalled_mask)
812 {
813 struct intel_engine_cs *engine;
814 enum intel_engine_id id;
815 int err;
816
817 /*
818 * Everything depends on having the GTT running, so we need to start
819 * there.
820 */
821 err = i915_ggtt_enable_hw(gt->i915);
822 if (err)
823 return err;
824
825 local_bh_disable();
826 for_each_engine(engine, gt, id)
827 __intel_engine_reset(engine, stalled_mask & engine->mask);
828 local_bh_enable();
829
830 intel_uc_reset(>->uc, ALL_ENGINES);
831
832 intel_ggtt_restore_fences(gt->ggtt);
833
834 return err;
835 }
836
reset_finish_engine(struct intel_engine_cs * engine)837 static void reset_finish_engine(struct intel_engine_cs *engine)
838 {
839 if (engine->reset.finish)
840 engine->reset.finish(engine);
841 intel_uncore_forcewake_put(engine->uncore, FORCEWAKE_ALL);
842
843 intel_engine_signal_breadcrumbs(engine);
844 }
845
reset_finish(struct intel_gt * gt,intel_engine_mask_t awake)846 static void reset_finish(struct intel_gt *gt, intel_engine_mask_t awake)
847 {
848 struct intel_engine_cs *engine;
849 enum intel_engine_id id;
850
851 for_each_engine(engine, gt, id) {
852 reset_finish_engine(engine);
853 if (awake & engine->mask)
854 intel_engine_pm_put(engine);
855 }
856
857 intel_uc_reset_finish(>->uc);
858 }
859
nop_submit_request(struct i915_request * request)860 static void nop_submit_request(struct i915_request *request)
861 {
862 RQ_TRACE(request, "-EIO\n");
863
864 request = i915_request_mark_eio(request);
865 if (request) {
866 i915_request_submit(request);
867 intel_engine_signal_breadcrumbs(request->engine);
868
869 i915_request_put(request);
870 }
871 }
872
__intel_gt_set_wedged(struct intel_gt * gt)873 static void __intel_gt_set_wedged(struct intel_gt *gt)
874 {
875 struct intel_engine_cs *engine;
876 intel_engine_mask_t awake;
877 enum intel_engine_id id;
878
879 if (test_bit(I915_WEDGED, >->reset.flags))
880 return;
881
882 GT_TRACE(gt, "start\n");
883
884 /*
885 * First, stop submission to hw, but do not yet complete requests by
886 * rolling the global seqno forward (since this would complete requests
887 * for which we haven't set the fence error to EIO yet).
888 */
889 awake = reset_prepare(gt);
890
891 /* Even if the GPU reset fails, it should still stop the engines */
892 if (!INTEL_INFO(gt->i915)->gpu_reset_clobbers_display)
893 __intel_gt_reset(gt, ALL_ENGINES);
894
895 for_each_engine(engine, gt, id)
896 engine->submit_request = nop_submit_request;
897
898 /*
899 * Make sure no request can slip through without getting completed by
900 * either this call here to intel_engine_write_global_seqno, or the one
901 * in nop_submit_request.
902 */
903 synchronize_rcu_expedited();
904 set_bit(I915_WEDGED, >->reset.flags);
905
906 /* Mark all executing requests as skipped */
907 local_bh_disable();
908 for_each_engine(engine, gt, id)
909 if (engine->reset.cancel)
910 engine->reset.cancel(engine);
911 intel_uc_cancel_requests(>->uc);
912 local_bh_enable();
913
914 reset_finish(gt, awake);
915
916 GT_TRACE(gt, "end\n");
917 }
918
intel_gt_set_wedged(struct intel_gt * gt)919 void intel_gt_set_wedged(struct intel_gt *gt)
920 {
921 intel_wakeref_t wakeref;
922
923 if (test_bit(I915_WEDGED, >->reset.flags))
924 return;
925
926 wakeref = intel_runtime_pm_get(gt->uncore->rpm);
927 mutex_lock(>->reset.mutex);
928
929 if (GEM_SHOW_DEBUG()) {
930 struct drm_printer p = drm_debug_printer(__func__);
931 struct intel_engine_cs *engine;
932 enum intel_engine_id id;
933
934 drm_printf(&p, "called from %pS\n", (void *)_RET_IP_);
935 for_each_engine(engine, gt, id) {
936 if (intel_engine_is_idle(engine))
937 continue;
938
939 intel_engine_dump(engine, &p, "%s\n", engine->name);
940 }
941 }
942
943 __intel_gt_set_wedged(gt);
944
945 mutex_unlock(>->reset.mutex);
946 intel_runtime_pm_put(gt->uncore->rpm, wakeref);
947 }
948
__intel_gt_unset_wedged(struct intel_gt * gt)949 static bool __intel_gt_unset_wedged(struct intel_gt *gt)
950 {
951 struct intel_gt_timelines *timelines = >->timelines;
952 struct intel_timeline *tl;
953 bool ok;
954
955 if (!test_bit(I915_WEDGED, >->reset.flags))
956 return true;
957
958 /* Never fully initialised, recovery impossible */
959 if (intel_gt_has_unrecoverable_error(gt))
960 return false;
961
962 GT_TRACE(gt, "start\n");
963
964 /*
965 * Before unwedging, make sure that all pending operations
966 * are flushed and errored out - we may have requests waiting upon
967 * third party fences. We marked all inflight requests as EIO, and
968 * every execbuf since returned EIO, for consistency we want all
969 * the currently pending requests to also be marked as EIO, which
970 * is done inside our nop_submit_request - and so we must wait.
971 *
972 * No more can be submitted until we reset the wedged bit.
973 */
974 spin_lock(&timelines->lock);
975 list_for_each_entry(tl, &timelines->active_list, link) {
976 struct dma_fence *fence;
977
978 fence = i915_active_fence_get(&tl->last_request);
979 if (!fence)
980 continue;
981
982 spin_unlock(&timelines->lock);
983
984 /*
985 * All internal dependencies (i915_requests) will have
986 * been flushed by the set-wedge, but we may be stuck waiting
987 * for external fences. These should all be capped to 10s
988 * (I915_FENCE_TIMEOUT) so this wait should not be unbounded
989 * in the worst case.
990 */
991 dma_fence_default_wait(fence, false, MAX_SCHEDULE_TIMEOUT);
992 dma_fence_put(fence);
993
994 /* Restart iteration after droping lock */
995 spin_lock(&timelines->lock);
996 tl = list_entry(&timelines->active_list, typeof(*tl), link);
997 }
998 spin_unlock(&timelines->lock);
999
1000 /* We must reset pending GPU events before restoring our submission */
1001 ok = !HAS_EXECLISTS(gt->i915); /* XXX better agnosticism desired */
1002 if (!INTEL_INFO(gt->i915)->gpu_reset_clobbers_display)
1003 ok = __intel_gt_reset(gt, ALL_ENGINES) == 0;
1004 if (!ok) {
1005 /*
1006 * Warn CI about the unrecoverable wedged condition.
1007 * Time for a reboot.
1008 */
1009 add_taint_for_CI(gt->i915, TAINT_WARN);
1010 return false;
1011 }
1012
1013 /*
1014 * Undo nop_submit_request. We prevent all new i915 requests from
1015 * being queued (by disallowing execbuf whilst wedged) so having
1016 * waited for all active requests above, we know the system is idle
1017 * and do not have to worry about a thread being inside
1018 * engine->submit_request() as we swap over. So unlike installing
1019 * the nop_submit_request on reset, we can do this from normal
1020 * context and do not require stop_machine().
1021 */
1022 intel_engines_reset_default_submission(gt);
1023
1024 GT_TRACE(gt, "end\n");
1025
1026 smp_mb__before_atomic(); /* complete takeover before enabling execbuf */
1027 clear_bit(I915_WEDGED, >->reset.flags);
1028
1029 return true;
1030 }
1031
intel_gt_unset_wedged(struct intel_gt * gt)1032 bool intel_gt_unset_wedged(struct intel_gt *gt)
1033 {
1034 bool result;
1035
1036 mutex_lock(>->reset.mutex);
1037 result = __intel_gt_unset_wedged(gt);
1038 mutex_unlock(>->reset.mutex);
1039
1040 return result;
1041 }
1042
do_reset(struct intel_gt * gt,intel_engine_mask_t stalled_mask)1043 static int do_reset(struct intel_gt *gt, intel_engine_mask_t stalled_mask)
1044 {
1045 int err, i;
1046
1047 err = __intel_gt_reset(gt, ALL_ENGINES);
1048 for (i = 0; err && i < RESET_MAX_RETRIES; i++) {
1049 msleep(10 * (i + 1));
1050 err = __intel_gt_reset(gt, ALL_ENGINES);
1051 }
1052 if (err)
1053 return err;
1054
1055 return gt_reset(gt, stalled_mask);
1056 }
1057
resume(struct intel_gt * gt)1058 static int resume(struct intel_gt *gt)
1059 {
1060 struct intel_engine_cs *engine;
1061 enum intel_engine_id id;
1062 int ret;
1063
1064 for_each_engine(engine, gt, id) {
1065 ret = intel_engine_resume(engine);
1066 if (ret)
1067 return ret;
1068 }
1069
1070 return 0;
1071 }
1072
1073 /**
1074 * intel_gt_reset - reset chip after a hang
1075 * @gt: #intel_gt to reset
1076 * @stalled_mask: mask of the stalled engines with the guilty requests
1077 * @reason: user error message for why we are resetting
1078 *
1079 * Reset the chip. Useful if a hang is detected. Marks the device as wedged
1080 * on failure.
1081 *
1082 * Procedure is fairly simple:
1083 * - reset the chip using the reset reg
1084 * - re-init context state
1085 * - re-init hardware status page
1086 * - re-init ring buffer
1087 * - re-init interrupt state
1088 * - re-init display
1089 */
intel_gt_reset(struct intel_gt * gt,intel_engine_mask_t stalled_mask,const char * reason)1090 void intel_gt_reset(struct intel_gt *gt,
1091 intel_engine_mask_t stalled_mask,
1092 const char *reason)
1093 {
1094 intel_engine_mask_t awake;
1095 int ret;
1096
1097 GT_TRACE(gt, "flags=%lx\n", gt->reset.flags);
1098
1099 might_sleep();
1100 GEM_BUG_ON(!test_bit(I915_RESET_BACKOFF, >->reset.flags));
1101
1102 /*
1103 * FIXME: Revoking cpu mmap ptes cannot be done from a dma_fence
1104 * critical section like gpu reset.
1105 */
1106 gt_revoke(gt);
1107
1108 mutex_lock(>->reset.mutex);
1109
1110 /* Clear any previous failed attempts at recovery. Time to try again. */
1111 if (!__intel_gt_unset_wedged(gt))
1112 goto unlock;
1113
1114 if (reason)
1115 drm_notice(>->i915->drm,
1116 "Resetting chip for %s\n", reason);
1117 atomic_inc(>->i915->gpu_error.reset_count);
1118
1119 awake = reset_prepare(gt);
1120
1121 if (!intel_has_gpu_reset(gt)) {
1122 if (gt->i915->params.reset)
1123 drm_err(>->i915->drm, "GPU reset not supported\n");
1124 else
1125 drm_dbg(>->i915->drm, "GPU reset disabled\n");
1126 goto error;
1127 }
1128
1129 if (INTEL_INFO(gt->i915)->gpu_reset_clobbers_display)
1130 intel_runtime_pm_disable_interrupts(gt->i915);
1131
1132 if (do_reset(gt, stalled_mask)) {
1133 drm_err(>->i915->drm, "Failed to reset chip\n");
1134 goto taint;
1135 }
1136
1137 if (INTEL_INFO(gt->i915)->gpu_reset_clobbers_display)
1138 intel_runtime_pm_enable_interrupts(gt->i915);
1139
1140 intel_overlay_reset(gt->i915);
1141
1142 /*
1143 * Next we need to restore the context, but we don't use those
1144 * yet either...
1145 *
1146 * Ring buffer needs to be re-initialized in the KMS case, or if X
1147 * was running at the time of the reset (i.e. we weren't VT
1148 * switched away).
1149 */
1150 ret = intel_gt_init_hw(gt);
1151 if (ret) {
1152 drm_err(>->i915->drm,
1153 "Failed to initialise HW following reset (%d)\n",
1154 ret);
1155 goto taint;
1156 }
1157
1158 ret = resume(gt);
1159 if (ret)
1160 goto taint;
1161
1162 finish:
1163 reset_finish(gt, awake);
1164 unlock:
1165 mutex_unlock(>->reset.mutex);
1166 return;
1167
1168 taint:
1169 /*
1170 * History tells us that if we cannot reset the GPU now, we
1171 * never will. This then impacts everything that is run
1172 * subsequently. On failing the reset, we mark the driver
1173 * as wedged, preventing further execution on the GPU.
1174 * We also want to go one step further and add a taint to the
1175 * kernel so that any subsequent faults can be traced back to
1176 * this failure. This is important for CI, where if the
1177 * GPU/driver fails we would like to reboot and restart testing
1178 * rather than continue on into oblivion. For everyone else,
1179 * the system should still plod along, but they have been warned!
1180 */
1181 add_taint_for_CI(gt->i915, TAINT_WARN);
1182 error:
1183 __intel_gt_set_wedged(gt);
1184 goto finish;
1185 }
1186
intel_gt_reset_engine(struct intel_engine_cs * engine)1187 static int intel_gt_reset_engine(struct intel_engine_cs *engine)
1188 {
1189 return __intel_gt_reset(engine->gt, engine->mask);
1190 }
1191
__intel_engine_reset_bh(struct intel_engine_cs * engine,const char * msg)1192 int __intel_engine_reset_bh(struct intel_engine_cs *engine, const char *msg)
1193 {
1194 struct intel_gt *gt = engine->gt;
1195 int ret;
1196
1197 ENGINE_TRACE(engine, "flags=%lx\n", gt->reset.flags);
1198 GEM_BUG_ON(!test_bit(I915_RESET_ENGINE + engine->id, >->reset.flags));
1199
1200 if (intel_engine_uses_guc(engine))
1201 return -ENODEV;
1202
1203 if (!intel_engine_pm_get_if_awake(engine))
1204 return 0;
1205
1206 reset_prepare_engine(engine);
1207
1208 if (msg)
1209 drm_notice(&engine->i915->drm,
1210 "Resetting %s for %s\n", engine->name, msg);
1211 atomic_inc(&engine->i915->gpu_error.reset_engine_count[engine->uabi_class]);
1212
1213 ret = intel_gt_reset_engine(engine);
1214 if (ret) {
1215 /* If we fail here, we expect to fallback to a global reset */
1216 ENGINE_TRACE(engine, "Failed to reset %s, err: %d\n", engine->name, ret);
1217 goto out;
1218 }
1219
1220 /*
1221 * The request that caused the hang is stuck on elsp, we know the
1222 * active request and can drop it, adjust head to skip the offending
1223 * request to resume executing remaining requests in the queue.
1224 */
1225 __intel_engine_reset(engine, true);
1226
1227 /*
1228 * The engine and its registers (and workarounds in case of render)
1229 * have been reset to their default values. Follow the init_ring
1230 * process to program RING_MODE, HWSP and re-enable submission.
1231 */
1232 ret = intel_engine_resume(engine);
1233
1234 out:
1235 intel_engine_cancel_stop_cs(engine);
1236 reset_finish_engine(engine);
1237 intel_engine_pm_put_async(engine);
1238 return ret;
1239 }
1240
1241 /**
1242 * intel_engine_reset - reset GPU engine to recover from a hang
1243 * @engine: engine to reset
1244 * @msg: reason for GPU reset; or NULL for no drm_notice()
1245 *
1246 * Reset a specific GPU engine. Useful if a hang is detected.
1247 * Returns zero on successful reset or otherwise an error code.
1248 *
1249 * Procedure is:
1250 * - identifies the request that caused the hang and it is dropped
1251 * - reset engine (which will force the engine to idle)
1252 * - re-init/configure engine
1253 */
intel_engine_reset(struct intel_engine_cs * engine,const char * msg)1254 int intel_engine_reset(struct intel_engine_cs *engine, const char *msg)
1255 {
1256 int err;
1257
1258 local_bh_disable();
1259 err = __intel_engine_reset_bh(engine, msg);
1260 local_bh_enable();
1261
1262 return err;
1263 }
1264
intel_gt_reset_global(struct intel_gt * gt,u32 engine_mask,const char * reason)1265 static void intel_gt_reset_global(struct intel_gt *gt,
1266 u32 engine_mask,
1267 const char *reason)
1268 {
1269 struct kobject *kobj = >->i915->drm.primary->kdev->kobj;
1270 char *error_event[] = { I915_ERROR_UEVENT "=1", NULL };
1271 char *reset_event[] = { I915_RESET_UEVENT "=1", NULL };
1272 char *reset_done_event[] = { I915_ERROR_UEVENT "=0", NULL };
1273 struct intel_wedge_me w;
1274
1275 kobject_uevent_env(kobj, KOBJ_CHANGE, error_event);
1276
1277 GT_TRACE(gt, "resetting chip, engines=%x\n", engine_mask);
1278 kobject_uevent_env(kobj, KOBJ_CHANGE, reset_event);
1279
1280 /* Use a watchdog to ensure that our reset completes */
1281 intel_wedge_on_timeout(&w, gt, 5 * HZ) {
1282 intel_display_prepare_reset(gt->i915);
1283
1284 /* Flush everyone using a resource about to be clobbered */
1285 synchronize_srcu_expedited(>->reset.backoff_srcu);
1286
1287 intel_gt_reset(gt, engine_mask, reason);
1288
1289 intel_display_finish_reset(gt->i915);
1290 }
1291
1292 if (!test_bit(I915_WEDGED, >->reset.flags))
1293 kobject_uevent_env(kobj, KOBJ_CHANGE, reset_done_event);
1294 }
1295
1296 /**
1297 * intel_gt_handle_error - handle a gpu error
1298 * @gt: the intel_gt
1299 * @engine_mask: mask representing engines that are hung
1300 * @flags: control flags
1301 * @fmt: Error message format string
1302 *
1303 * Do some basic checking of register state at error time and
1304 * dump it to the syslog. Also call i915_capture_error_state() to make
1305 * sure we get a record and make it available in debugfs. Fire a uevent
1306 * so userspace knows something bad happened (should trigger collection
1307 * of a ring dump etc.).
1308 */
intel_gt_handle_error(struct intel_gt * gt,intel_engine_mask_t engine_mask,unsigned long flags,const char * fmt,...)1309 void intel_gt_handle_error(struct intel_gt *gt,
1310 intel_engine_mask_t engine_mask,
1311 unsigned long flags,
1312 const char *fmt, ...)
1313 {
1314 struct intel_engine_cs *engine;
1315 intel_wakeref_t wakeref;
1316 intel_engine_mask_t tmp;
1317 char error_msg[80];
1318 char *msg = NULL;
1319
1320 if (fmt) {
1321 va_list args;
1322
1323 va_start(args, fmt);
1324 vscnprintf(error_msg, sizeof(error_msg), fmt, args);
1325 va_end(args);
1326
1327 msg = error_msg;
1328 }
1329
1330 /*
1331 * In most cases it's guaranteed that we get here with an RPM
1332 * reference held, for example because there is a pending GPU
1333 * request that won't finish until the reset is done. This
1334 * isn't the case at least when we get here by doing a
1335 * simulated reset via debugfs, so get an RPM reference.
1336 */
1337 wakeref = intel_runtime_pm_get(gt->uncore->rpm);
1338
1339 engine_mask &= gt->info.engine_mask;
1340
1341 if (flags & I915_ERROR_CAPTURE) {
1342 i915_capture_error_state(gt, engine_mask, CORE_DUMP_FLAG_NONE);
1343 intel_gt_clear_error_registers(gt, engine_mask);
1344 }
1345
1346 /*
1347 * Try engine reset when available. We fall back to full reset if
1348 * single reset fails.
1349 */
1350 if (!intel_uc_uses_guc_submission(>->uc) &&
1351 intel_has_reset_engine(gt) && !intel_gt_is_wedged(gt)) {
1352 local_bh_disable();
1353 for_each_engine_masked(engine, gt, engine_mask, tmp) {
1354 BUILD_BUG_ON(I915_RESET_MODESET >= I915_RESET_ENGINE);
1355 if (test_and_set_bit(I915_RESET_ENGINE + engine->id,
1356 >->reset.flags))
1357 continue;
1358
1359 if (__intel_engine_reset_bh(engine, msg) == 0)
1360 engine_mask &= ~engine->mask;
1361
1362 clear_and_wake_up_bit(I915_RESET_ENGINE + engine->id,
1363 >->reset.flags);
1364 }
1365 local_bh_enable();
1366 }
1367
1368 if (!engine_mask)
1369 goto out;
1370
1371 /* Full reset needs the mutex, stop any other user trying to do so. */
1372 if (test_and_set_bit(I915_RESET_BACKOFF, >->reset.flags)) {
1373 wait_event(gt->reset.queue,
1374 !test_bit(I915_RESET_BACKOFF, >->reset.flags));
1375 goto out; /* piggy-back on the other reset */
1376 }
1377
1378 /* Make sure i915_reset_trylock() sees the I915_RESET_BACKOFF */
1379 synchronize_rcu_expedited();
1380
1381 /*
1382 * Prevent any other reset-engine attempt. We don't do this for GuC
1383 * submission the GuC owns the per-engine reset, not the i915.
1384 */
1385 if (!intel_uc_uses_guc_submission(>->uc)) {
1386 for_each_engine(engine, gt, tmp) {
1387 while (test_and_set_bit(I915_RESET_ENGINE + engine->id,
1388 >->reset.flags))
1389 wait_on_bit(>->reset.flags,
1390 I915_RESET_ENGINE + engine->id,
1391 TASK_UNINTERRUPTIBLE);
1392 }
1393 }
1394
1395 intel_gt_reset_global(gt, engine_mask, msg);
1396
1397 if (!intel_uc_uses_guc_submission(>->uc)) {
1398 for_each_engine(engine, gt, tmp)
1399 clear_bit_unlock(I915_RESET_ENGINE + engine->id,
1400 >->reset.flags);
1401 }
1402 clear_bit_unlock(I915_RESET_BACKOFF, >->reset.flags);
1403 smp_mb__after_atomic();
1404 wake_up_all(>->reset.queue);
1405
1406 out:
1407 intel_runtime_pm_put(gt->uncore->rpm, wakeref);
1408 }
1409
intel_gt_reset_trylock(struct intel_gt * gt,int * srcu)1410 int intel_gt_reset_trylock(struct intel_gt *gt, int *srcu)
1411 {
1412 might_lock(>->reset.backoff_srcu);
1413 might_sleep();
1414
1415 rcu_read_lock();
1416 while (test_bit(I915_RESET_BACKOFF, >->reset.flags)) {
1417 rcu_read_unlock();
1418
1419 if (wait_event_interruptible(gt->reset.queue,
1420 !test_bit(I915_RESET_BACKOFF,
1421 >->reset.flags)))
1422 return -EINTR;
1423
1424 rcu_read_lock();
1425 }
1426 *srcu = srcu_read_lock(>->reset.backoff_srcu);
1427 rcu_read_unlock();
1428
1429 return 0;
1430 }
1431
intel_gt_reset_unlock(struct intel_gt * gt,int tag)1432 void intel_gt_reset_unlock(struct intel_gt *gt, int tag)
1433 __releases(>->reset.backoff_srcu)
1434 {
1435 srcu_read_unlock(>->reset.backoff_srcu, tag);
1436 }
1437
intel_gt_terminally_wedged(struct intel_gt * gt)1438 int intel_gt_terminally_wedged(struct intel_gt *gt)
1439 {
1440 might_sleep();
1441
1442 if (!intel_gt_is_wedged(gt))
1443 return 0;
1444
1445 if (intel_gt_has_unrecoverable_error(gt))
1446 return -EIO;
1447
1448 /* Reset still in progress? Maybe we will recover? */
1449 if (wait_event_interruptible(gt->reset.queue,
1450 !test_bit(I915_RESET_BACKOFF,
1451 >->reset.flags)))
1452 return -EINTR;
1453
1454 return intel_gt_is_wedged(gt) ? -EIO : 0;
1455 }
1456
intel_gt_set_wedged_on_init(struct intel_gt * gt)1457 void intel_gt_set_wedged_on_init(struct intel_gt *gt)
1458 {
1459 BUILD_BUG_ON(I915_RESET_ENGINE + I915_NUM_ENGINES >
1460 I915_WEDGED_ON_INIT);
1461 intel_gt_set_wedged(gt);
1462 i915_disable_error_state(gt->i915, -ENODEV);
1463 set_bit(I915_WEDGED_ON_INIT, >->reset.flags);
1464
1465 /* Wedged on init is non-recoverable */
1466 add_taint_for_CI(gt->i915, TAINT_WARN);
1467 }
1468
intel_gt_set_wedged_on_fini(struct intel_gt * gt)1469 void intel_gt_set_wedged_on_fini(struct intel_gt *gt)
1470 {
1471 intel_gt_set_wedged(gt);
1472 i915_disable_error_state(gt->i915, -ENODEV);
1473 set_bit(I915_WEDGED_ON_FINI, >->reset.flags);
1474 intel_gt_retire_requests(gt); /* cleanup any wedged requests */
1475 }
1476
intel_gt_init_reset(struct intel_gt * gt)1477 void intel_gt_init_reset(struct intel_gt *gt)
1478 {
1479 init_waitqueue_head(>->reset.queue);
1480 mutex_init(>->reset.mutex);
1481 init_srcu_struct(>->reset.backoff_srcu);
1482
1483 /*
1484 * While undesirable to wait inside the shrinker, complain anyway.
1485 *
1486 * If we have to wait during shrinking, we guarantee forward progress
1487 * by forcing the reset. Therefore during the reset we must not
1488 * re-enter the shrinker. By declaring that we take the reset mutex
1489 * within the shrinker, we forbid ourselves from performing any
1490 * fs-reclaim or taking related locks during reset.
1491 */
1492 i915_gem_shrinker_taints_mutex(gt->i915, >->reset.mutex);
1493
1494 /* no GPU until we are ready! */
1495 __set_bit(I915_WEDGED, >->reset.flags);
1496 }
1497
intel_gt_fini_reset(struct intel_gt * gt)1498 void intel_gt_fini_reset(struct intel_gt *gt)
1499 {
1500 cleanup_srcu_struct(>->reset.backoff_srcu);
1501 }
1502
intel_wedge_me(struct work_struct * work)1503 static void intel_wedge_me(struct work_struct *work)
1504 {
1505 struct intel_wedge_me *w = container_of(work, typeof(*w), work.work);
1506
1507 drm_err(&w->gt->i915->drm,
1508 "%s timed out, cancelling all in-flight rendering.\n",
1509 w->name);
1510 intel_gt_set_wedged(w->gt);
1511 }
1512
__intel_init_wedge(struct intel_wedge_me * w,struct intel_gt * gt,long timeout,const char * name)1513 void __intel_init_wedge(struct intel_wedge_me *w,
1514 struct intel_gt *gt,
1515 long timeout,
1516 const char *name)
1517 {
1518 w->gt = gt;
1519 w->name = name;
1520
1521 INIT_DELAYED_WORK_ONSTACK(&w->work, intel_wedge_me);
1522 schedule_delayed_work(&w->work, timeout);
1523 }
1524
__intel_fini_wedge(struct intel_wedge_me * w)1525 void __intel_fini_wedge(struct intel_wedge_me *w)
1526 {
1527 cancel_delayed_work_sync(&w->work);
1528 destroy_delayed_work_on_stack(&w->work);
1529 w->gt = NULL;
1530 }
1531
1532 #if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
1533 #include "selftest_reset.c"
1534 #include "selftest_hangcheck.c"
1535 #endif
1536