1 // SPDX-License-Identifier: MIT
2 /*
3  * Copyright © 2008-2021 Intel Corporation
4  */
5 
6 #include <drm/drm_cache.h>
7 
8 #include "gem/i915_gem_internal.h"
9 
10 #include "gen2_engine_cs.h"
11 #include "gen6_engine_cs.h"
12 #include "gen6_ppgtt.h"
13 #include "gen7_renderclear.h"
14 #include "i915_drv.h"
15 #include "i915_mitigations.h"
16 #include "intel_breadcrumbs.h"
17 #include "intel_context.h"
18 #include "intel_engine_regs.h"
19 #include "intel_gt.h"
20 #include "intel_gt_irq.h"
21 #include "intel_gt_regs.h"
22 #include "intel_reset.h"
23 #include "intel_ring.h"
24 #include "shmem_utils.h"
25 #include "intel_engine_heartbeat.h"
26 #include "intel_engine_pm.h"
27 
28 /* Rough estimate of the typical request size, performing a flush,
29  * set-context and then emitting the batch.
30  */
31 #define LEGACY_REQUEST_SIZE 200
32 
33 static void set_hwstam(struct intel_engine_cs *engine, u32 mask)
34 {
35 	/*
36 	 * Keep the render interrupt unmasked as this papers over
37 	 * lost interrupts following a reset.
38 	 */
39 	if (engine->class == RENDER_CLASS) {
40 		if (GRAPHICS_VER(engine->i915) >= 6)
41 			mask &= ~BIT(0);
42 		else
43 			mask &= ~I915_USER_INTERRUPT;
44 	}
45 
46 	intel_engine_set_hwsp_writemask(engine, mask);
47 }
48 
49 static void set_hws_pga(struct intel_engine_cs *engine, phys_addr_t phys)
50 {
51 	u32 addr;
52 
53 	addr = lower_32_bits(phys);
54 	if (GRAPHICS_VER(engine->i915) >= 4)
55 		addr |= (phys >> 28) & 0xf0;
56 
57 	intel_uncore_write(engine->uncore, HWS_PGA, addr);
58 }
59 
60 static struct page *status_page(struct intel_engine_cs *engine)
61 {
62 	struct drm_i915_gem_object *obj = engine->status_page.vma->obj;
63 
64 	GEM_BUG_ON(!i915_gem_object_has_pinned_pages(obj));
65 	return sg_page(obj->mm.pages->sgl);
66 }
67 
68 static void ring_setup_phys_status_page(struct intel_engine_cs *engine)
69 {
70 	set_hws_pga(engine, PFN_PHYS(page_to_pfn(status_page(engine))));
71 	set_hwstam(engine, ~0u);
72 }
73 
74 static void set_hwsp(struct intel_engine_cs *engine, u32 offset)
75 {
76 	i915_reg_t hwsp;
77 
78 	/*
79 	 * The ring status page addresses are no longer next to the rest of
80 	 * the ring registers as of gen7.
81 	 */
82 	if (GRAPHICS_VER(engine->i915) == 7) {
83 		switch (engine->id) {
84 		/*
85 		 * No more rings exist on Gen7. Default case is only to shut up
86 		 * gcc switch check warning.
87 		 */
88 		default:
89 			GEM_BUG_ON(engine->id);
90 			fallthrough;
91 		case RCS0:
92 			hwsp = RENDER_HWS_PGA_GEN7;
93 			break;
94 		case BCS0:
95 			hwsp = BLT_HWS_PGA_GEN7;
96 			break;
97 		case VCS0:
98 			hwsp = BSD_HWS_PGA_GEN7;
99 			break;
100 		case VECS0:
101 			hwsp = VEBOX_HWS_PGA_GEN7;
102 			break;
103 		}
104 	} else if (GRAPHICS_VER(engine->i915) == 6) {
105 		hwsp = RING_HWS_PGA_GEN6(engine->mmio_base);
106 	} else {
107 		hwsp = RING_HWS_PGA(engine->mmio_base);
108 	}
109 
110 	intel_uncore_write_fw(engine->uncore, hwsp, offset);
111 	intel_uncore_posting_read_fw(engine->uncore, hwsp);
112 }
113 
114 static void flush_cs_tlb(struct intel_engine_cs *engine)
115 {
116 	if (!IS_GRAPHICS_VER(engine->i915, 6, 7))
117 		return;
118 
119 	/* ring should be idle before issuing a sync flush*/
120 	if ((ENGINE_READ(engine, RING_MI_MODE) & MODE_IDLE) == 0)
121 		drm_warn(&engine->i915->drm, "%s not idle before sync flush!\n",
122 			 engine->name);
123 
124 	ENGINE_WRITE_FW(engine, RING_INSTPM,
125 			_MASKED_BIT_ENABLE(INSTPM_TLB_INVALIDATE |
126 					   INSTPM_SYNC_FLUSH));
127 	if (__intel_wait_for_register_fw(engine->uncore,
128 					 RING_INSTPM(engine->mmio_base),
129 					 INSTPM_SYNC_FLUSH, 0,
130 					 2000, 0, NULL))
131 		ENGINE_TRACE(engine,
132 			     "wait for SyncFlush to complete for TLB invalidation timed out\n");
133 }
134 
135 static void ring_setup_status_page(struct intel_engine_cs *engine)
136 {
137 	set_hwsp(engine, i915_ggtt_offset(engine->status_page.vma));
138 	set_hwstam(engine, ~0u);
139 
140 	flush_cs_tlb(engine);
141 }
142 
143 static struct i915_address_space *vm_alias(struct i915_address_space *vm)
144 {
145 	if (i915_is_ggtt(vm))
146 		vm = &i915_vm_to_ggtt(vm)->alias->vm;
147 
148 	return vm;
149 }
150 
151 static u32 pp_dir(struct i915_address_space *vm)
152 {
153 	return to_gen6_ppgtt(i915_vm_to_ppgtt(vm))->pp_dir;
154 }
155 
156 static void set_pp_dir(struct intel_engine_cs *engine)
157 {
158 	struct i915_address_space *vm = vm_alias(engine->gt->vm);
159 
160 	if (!vm)
161 		return;
162 
163 	ENGINE_WRITE_FW(engine, RING_PP_DIR_DCLV, PP_DIR_DCLV_2G);
164 	ENGINE_WRITE_FW(engine, RING_PP_DIR_BASE, pp_dir(vm));
165 
166 	if (GRAPHICS_VER(engine->i915) >= 7) {
167 		ENGINE_WRITE_FW(engine,
168 				RING_MODE_GEN7,
169 				_MASKED_BIT_ENABLE(GFX_PPGTT_ENABLE));
170 	}
171 }
172 
173 static bool stop_ring(struct intel_engine_cs *engine)
174 {
175 	/* Empty the ring by skipping to the end */
176 	ENGINE_WRITE_FW(engine, RING_HEAD, ENGINE_READ_FW(engine, RING_TAIL));
177 	ENGINE_POSTING_READ(engine, RING_HEAD);
178 
179 	/* The ring must be empty before it is disabled */
180 	ENGINE_WRITE_FW(engine, RING_CTL, 0);
181 	ENGINE_POSTING_READ(engine, RING_CTL);
182 
183 	/* Then reset the disabled ring */
184 	ENGINE_WRITE_FW(engine, RING_HEAD, 0);
185 	ENGINE_WRITE_FW(engine, RING_TAIL, 0);
186 
187 	return (ENGINE_READ_FW(engine, RING_HEAD) & HEAD_ADDR) == 0;
188 }
189 
190 static int xcs_resume(struct intel_engine_cs *engine)
191 {
192 	struct intel_ring *ring = engine->legacy.ring;
193 
194 	ENGINE_TRACE(engine, "ring:{HEAD:%04x, TAIL:%04x}\n",
195 		     ring->head, ring->tail);
196 
197 	/*
198 	 * Double check the ring is empty & disabled before we resume. Called
199 	 * from atomic context during PCI probe, so _hardirq().
200 	 */
201 	intel_synchronize_hardirq(engine->i915);
202 	if (!stop_ring(engine))
203 		goto err;
204 
205 	if (HWS_NEEDS_PHYSICAL(engine->i915))
206 		ring_setup_phys_status_page(engine);
207 	else
208 		ring_setup_status_page(engine);
209 
210 	intel_breadcrumbs_reset(engine->breadcrumbs);
211 
212 	/* Enforce ordering by reading HEAD register back */
213 	ENGINE_POSTING_READ(engine, RING_HEAD);
214 
215 	/*
216 	 * Initialize the ring. This must happen _after_ we've cleared the ring
217 	 * registers with the above sequence (the readback of the HEAD registers
218 	 * also enforces ordering), otherwise the hw might lose the new ring
219 	 * register values.
220 	 */
221 	ENGINE_WRITE_FW(engine, RING_START, i915_ggtt_offset(ring->vma));
222 
223 	/* Check that the ring offsets point within the ring! */
224 	GEM_BUG_ON(!intel_ring_offset_valid(ring, ring->head));
225 	GEM_BUG_ON(!intel_ring_offset_valid(ring, ring->tail));
226 	intel_ring_update_space(ring);
227 
228 	set_pp_dir(engine);
229 
230 	/* First wake the ring up to an empty/idle ring */
231 	ENGINE_WRITE_FW(engine, RING_HEAD, ring->head);
232 	ENGINE_WRITE_FW(engine, RING_TAIL, ring->head);
233 	ENGINE_POSTING_READ(engine, RING_TAIL);
234 
235 	ENGINE_WRITE_FW(engine, RING_CTL,
236 			RING_CTL_SIZE(ring->size) | RING_VALID);
237 
238 	/* If the head is still not zero, the ring is dead */
239 	if (__intel_wait_for_register_fw(engine->uncore,
240 					 RING_CTL(engine->mmio_base),
241 					 RING_VALID, RING_VALID,
242 					 5000, 0, NULL))
243 		goto err;
244 
245 	if (GRAPHICS_VER(engine->i915) > 2)
246 		ENGINE_WRITE_FW(engine,
247 				RING_MI_MODE, _MASKED_BIT_DISABLE(STOP_RING));
248 
249 	/* Now awake, let it get started */
250 	if (ring->tail != ring->head) {
251 		ENGINE_WRITE_FW(engine, RING_TAIL, ring->tail);
252 		ENGINE_POSTING_READ(engine, RING_TAIL);
253 	}
254 
255 	/* Papering over lost _interrupts_ immediately following the restart */
256 	intel_engine_signal_breadcrumbs(engine);
257 	return 0;
258 
259 err:
260 	drm_err(&engine->i915->drm,
261 		"%s initialization failed; "
262 		"ctl %08x (valid? %d) head %08x [%08x] tail %08x [%08x] start %08x [expected %08x]\n",
263 		engine->name,
264 		ENGINE_READ(engine, RING_CTL),
265 		ENGINE_READ(engine, RING_CTL) & RING_VALID,
266 		ENGINE_READ(engine, RING_HEAD), ring->head,
267 		ENGINE_READ(engine, RING_TAIL), ring->tail,
268 		ENGINE_READ(engine, RING_START),
269 		i915_ggtt_offset(ring->vma));
270 	return -EIO;
271 }
272 
273 static void sanitize_hwsp(struct intel_engine_cs *engine)
274 {
275 	struct intel_timeline *tl;
276 
277 	list_for_each_entry(tl, &engine->status_page.timelines, engine_link)
278 		intel_timeline_reset_seqno(tl);
279 }
280 
281 static void xcs_sanitize(struct intel_engine_cs *engine)
282 {
283 	/*
284 	 * Poison residual state on resume, in case the suspend didn't!
285 	 *
286 	 * We have to assume that across suspend/resume (or other loss
287 	 * of control) that the contents of our pinned buffers has been
288 	 * lost, replaced by garbage. Since this doesn't always happen,
289 	 * let's poison such state so that we more quickly spot when
290 	 * we falsely assume it has been preserved.
291 	 */
292 	if (IS_ENABLED(CONFIG_DRM_I915_DEBUG_GEM))
293 		memset(engine->status_page.addr, POISON_INUSE, PAGE_SIZE);
294 
295 	/*
296 	 * The kernel_context HWSP is stored in the status_page. As above,
297 	 * that may be lost on resume/initialisation, and so we need to
298 	 * reset the value in the HWSP.
299 	 */
300 	sanitize_hwsp(engine);
301 
302 	/* And scrub the dirty cachelines for the HWSP */
303 	drm_clflush_virt_range(engine->status_page.addr, PAGE_SIZE);
304 
305 	intel_engine_reset_pinned_contexts(engine);
306 }
307 
308 static void reset_prepare(struct intel_engine_cs *engine)
309 {
310 	/*
311 	 * We stop engines, otherwise we might get failed reset and a
312 	 * dead gpu (on elk). Also as modern gpu as kbl can suffer
313 	 * from system hang if batchbuffer is progressing when
314 	 * the reset is issued, regardless of READY_TO_RESET ack.
315 	 * Thus assume it is best to stop engines on all gens
316 	 * where we have a gpu reset.
317 	 *
318 	 * WaKBLVECSSemaphoreWaitPoll:kbl (on ALL_ENGINES)
319 	 *
320 	 * WaMediaResetMainRingCleanup:ctg,elk (presumably)
321 	 * WaClearRingBufHeadRegAtInit:ctg,elk
322 	 *
323 	 * FIXME: Wa for more modern gens needs to be validated
324 	 */
325 	ENGINE_TRACE(engine, "\n");
326 	intel_engine_stop_cs(engine);
327 
328 	if (!stop_ring(engine)) {
329 		/* G45 ring initialization often fails to reset head to zero */
330 		ENGINE_TRACE(engine,
331 			     "HEAD not reset to zero, "
332 			     "{ CTL:%08x, HEAD:%08x, TAIL:%08x, START:%08x }\n",
333 			     ENGINE_READ_FW(engine, RING_CTL),
334 			     ENGINE_READ_FW(engine, RING_HEAD),
335 			     ENGINE_READ_FW(engine, RING_TAIL),
336 			     ENGINE_READ_FW(engine, RING_START));
337 		if (!stop_ring(engine)) {
338 			drm_err(&engine->i915->drm,
339 				"failed to set %s head to zero "
340 				"ctl %08x head %08x tail %08x start %08x\n",
341 				engine->name,
342 				ENGINE_READ_FW(engine, RING_CTL),
343 				ENGINE_READ_FW(engine, RING_HEAD),
344 				ENGINE_READ_FW(engine, RING_TAIL),
345 				ENGINE_READ_FW(engine, RING_START));
346 		}
347 	}
348 }
349 
350 static void reset_rewind(struct intel_engine_cs *engine, bool stalled)
351 {
352 	struct i915_request *pos, *rq;
353 	unsigned long flags;
354 	u32 head;
355 
356 	rq = NULL;
357 	spin_lock_irqsave(&engine->sched_engine->lock, flags);
358 	rcu_read_lock();
359 	list_for_each_entry(pos, &engine->sched_engine->requests, sched.link) {
360 		if (!__i915_request_is_complete(pos)) {
361 			rq = pos;
362 			break;
363 		}
364 	}
365 	rcu_read_unlock();
366 
367 	/*
368 	 * The guilty request will get skipped on a hung engine.
369 	 *
370 	 * Users of client default contexts do not rely on logical
371 	 * state preserved between batches so it is safe to execute
372 	 * queued requests following the hang. Non default contexts
373 	 * rely on preserved state, so skipping a batch loses the
374 	 * evolution of the state and it needs to be considered corrupted.
375 	 * Executing more queued batches on top of corrupted state is
376 	 * risky. But we take the risk by trying to advance through
377 	 * the queued requests in order to make the client behaviour
378 	 * more predictable around resets, by not throwing away random
379 	 * amount of batches it has prepared for execution. Sophisticated
380 	 * clients can use gem_reset_stats_ioctl and dma fence status
381 	 * (exported via sync_file info ioctl on explicit fences) to observe
382 	 * when it loses the context state and should rebuild accordingly.
383 	 *
384 	 * The context ban, and ultimately the client ban, mechanism are safety
385 	 * valves if client submission ends up resulting in nothing more than
386 	 * subsequent hangs.
387 	 */
388 
389 	if (rq) {
390 		/*
391 		 * Try to restore the logical GPU state to match the
392 		 * continuation of the request queue. If we skip the
393 		 * context/PD restore, then the next request may try to execute
394 		 * assuming that its context is valid and loaded on the GPU and
395 		 * so may try to access invalid memory, prompting repeated GPU
396 		 * hangs.
397 		 *
398 		 * If the request was guilty, we still restore the logical
399 		 * state in case the next request requires it (e.g. the
400 		 * aliasing ppgtt), but skip over the hung batch.
401 		 *
402 		 * If the request was innocent, we try to replay the request
403 		 * with the restored context.
404 		 */
405 		__i915_request_reset(rq, stalled);
406 
407 		GEM_BUG_ON(rq->ring != engine->legacy.ring);
408 		head = rq->head;
409 	} else {
410 		head = engine->legacy.ring->tail;
411 	}
412 	engine->legacy.ring->head = intel_ring_wrap(engine->legacy.ring, head);
413 
414 	spin_unlock_irqrestore(&engine->sched_engine->lock, flags);
415 }
416 
417 static void reset_finish(struct intel_engine_cs *engine)
418 {
419 }
420 
421 static void reset_cancel(struct intel_engine_cs *engine)
422 {
423 	struct i915_request *request;
424 	unsigned long flags;
425 
426 	spin_lock_irqsave(&engine->sched_engine->lock, flags);
427 
428 	/* Mark all submitted requests as skipped. */
429 	list_for_each_entry(request, &engine->sched_engine->requests, sched.link)
430 		i915_request_put(i915_request_mark_eio(request));
431 	intel_engine_signal_breadcrumbs(engine);
432 
433 	/* Remaining _unready_ requests will be nop'ed when submitted */
434 
435 	spin_unlock_irqrestore(&engine->sched_engine->lock, flags);
436 }
437 
438 static void i9xx_submit_request(struct i915_request *request)
439 {
440 	i915_request_submit(request);
441 	wmb(); /* paranoid flush writes out of the WCB before mmio */
442 
443 	ENGINE_WRITE(request->engine, RING_TAIL,
444 		     intel_ring_set_tail(request->ring, request->tail));
445 }
446 
447 static void __ring_context_fini(struct intel_context *ce)
448 {
449 	i915_vma_put(ce->state);
450 }
451 
452 static void ring_context_destroy(struct kref *ref)
453 {
454 	struct intel_context *ce = container_of(ref, typeof(*ce), ref);
455 
456 	GEM_BUG_ON(intel_context_is_pinned(ce));
457 
458 	if (ce->state)
459 		__ring_context_fini(ce);
460 
461 	intel_context_fini(ce);
462 	intel_context_free(ce);
463 }
464 
465 static int ring_context_init_default_state(struct intel_context *ce,
466 					   struct i915_gem_ww_ctx *ww)
467 {
468 	struct drm_i915_gem_object *obj = ce->state->obj;
469 	void *vaddr;
470 
471 	vaddr = i915_gem_object_pin_map(obj, I915_MAP_WB);
472 	if (IS_ERR(vaddr))
473 		return PTR_ERR(vaddr);
474 
475 	shmem_read(ce->engine->default_state, 0,
476 		   vaddr, ce->engine->context_size);
477 
478 	i915_gem_object_flush_map(obj);
479 	__i915_gem_object_release_map(obj);
480 
481 	__set_bit(CONTEXT_VALID_BIT, &ce->flags);
482 	return 0;
483 }
484 
485 static int ring_context_pre_pin(struct intel_context *ce,
486 				struct i915_gem_ww_ctx *ww,
487 				void **unused)
488 {
489 	struct i915_address_space *vm;
490 	int err = 0;
491 
492 	if (ce->engine->default_state &&
493 	    !test_bit(CONTEXT_VALID_BIT, &ce->flags)) {
494 		err = ring_context_init_default_state(ce, ww);
495 		if (err)
496 			return err;
497 	}
498 
499 	vm = vm_alias(ce->vm);
500 	if (vm)
501 		err = gen6_ppgtt_pin(i915_vm_to_ppgtt((vm)), ww);
502 
503 	return err;
504 }
505 
506 static void __context_unpin_ppgtt(struct intel_context *ce)
507 {
508 	struct i915_address_space *vm;
509 
510 	vm = vm_alias(ce->vm);
511 	if (vm)
512 		gen6_ppgtt_unpin(i915_vm_to_ppgtt(vm));
513 }
514 
515 static void ring_context_unpin(struct intel_context *ce)
516 {
517 }
518 
519 static void ring_context_post_unpin(struct intel_context *ce)
520 {
521 	__context_unpin_ppgtt(ce);
522 }
523 
524 static struct i915_vma *
525 alloc_context_vma(struct intel_engine_cs *engine)
526 {
527 	struct drm_i915_private *i915 = engine->i915;
528 	struct drm_i915_gem_object *obj;
529 	struct i915_vma *vma;
530 	int err;
531 
532 	obj = i915_gem_object_create_shmem(i915, engine->context_size);
533 	if (IS_ERR(obj))
534 		return ERR_CAST(obj);
535 
536 	/*
537 	 * Try to make the context utilize L3 as well as LLC.
538 	 *
539 	 * On VLV we don't have L3 controls in the PTEs so we
540 	 * shouldn't touch the cache level, especially as that
541 	 * would make the object snooped which might have a
542 	 * negative performance impact.
543 	 *
544 	 * Snooping is required on non-llc platforms in execlist
545 	 * mode, but since all GGTT accesses use PAT entry 0 we
546 	 * get snooping anyway regardless of cache_level.
547 	 *
548 	 * This is only applicable for Ivy Bridge devices since
549 	 * later platforms don't have L3 control bits in the PTE.
550 	 */
551 	if (IS_IVYBRIDGE(i915))
552 		i915_gem_object_set_cache_coherency(obj, I915_CACHE_L3_LLC);
553 
554 	vma = i915_vma_instance(obj, &engine->gt->ggtt->vm, NULL);
555 	if (IS_ERR(vma)) {
556 		err = PTR_ERR(vma);
557 		goto err_obj;
558 	}
559 
560 	return vma;
561 
562 err_obj:
563 	i915_gem_object_put(obj);
564 	return ERR_PTR(err);
565 }
566 
567 static int ring_context_alloc(struct intel_context *ce)
568 {
569 	struct intel_engine_cs *engine = ce->engine;
570 
571 	/* One ringbuffer to rule them all */
572 	GEM_BUG_ON(!engine->legacy.ring);
573 	ce->ring = engine->legacy.ring;
574 	ce->timeline = intel_timeline_get(engine->legacy.timeline);
575 
576 	GEM_BUG_ON(ce->state);
577 	if (engine->context_size) {
578 		struct i915_vma *vma;
579 
580 		vma = alloc_context_vma(engine);
581 		if (IS_ERR(vma))
582 			return PTR_ERR(vma);
583 
584 		ce->state = vma;
585 	}
586 
587 	return 0;
588 }
589 
590 static int ring_context_pin(struct intel_context *ce, void *unused)
591 {
592 	return 0;
593 }
594 
595 static void ring_context_reset(struct intel_context *ce)
596 {
597 	intel_ring_reset(ce->ring, ce->ring->emit);
598 	clear_bit(CONTEXT_VALID_BIT, &ce->flags);
599 }
600 
601 static void ring_context_ban(struct intel_context *ce,
602 			     struct i915_request *rq)
603 {
604 	struct intel_engine_cs *engine;
605 
606 	if (!rq || !i915_request_is_active(rq))
607 		return;
608 
609 	engine = rq->engine;
610 	lockdep_assert_held(&engine->sched_engine->lock);
611 	list_for_each_entry_continue(rq, &engine->sched_engine->requests,
612 				     sched.link)
613 		if (rq->context == ce) {
614 			i915_request_set_error_once(rq, -EIO);
615 			__i915_request_skip(rq);
616 		}
617 }
618 
619 static void ring_context_cancel_request(struct intel_context *ce,
620 					struct i915_request *rq)
621 {
622 	struct intel_engine_cs *engine = NULL;
623 
624 	i915_request_active_engine(rq, &engine);
625 
626 	if (engine && intel_engine_pulse(engine))
627 		intel_gt_handle_error(engine->gt, engine->mask, 0,
628 				      "request cancellation by %s",
629 				      current->comm);
630 }
631 
632 static const struct intel_context_ops ring_context_ops = {
633 	.alloc = ring_context_alloc,
634 
635 	.cancel_request = ring_context_cancel_request,
636 
637 	.ban = ring_context_ban,
638 
639 	.pre_pin = ring_context_pre_pin,
640 	.pin = ring_context_pin,
641 	.unpin = ring_context_unpin,
642 	.post_unpin = ring_context_post_unpin,
643 
644 	.enter = intel_context_enter_engine,
645 	.exit = intel_context_exit_engine,
646 
647 	.reset = ring_context_reset,
648 	.destroy = ring_context_destroy,
649 };
650 
651 static int load_pd_dir(struct i915_request *rq,
652 		       struct i915_address_space *vm,
653 		       u32 valid)
654 {
655 	const struct intel_engine_cs * const engine = rq->engine;
656 	u32 *cs;
657 
658 	cs = intel_ring_begin(rq, 12);
659 	if (IS_ERR(cs))
660 		return PTR_ERR(cs);
661 
662 	*cs++ = MI_LOAD_REGISTER_IMM(1);
663 	*cs++ = i915_mmio_reg_offset(RING_PP_DIR_DCLV(engine->mmio_base));
664 	*cs++ = valid;
665 
666 	*cs++ = MI_LOAD_REGISTER_IMM(1);
667 	*cs++ = i915_mmio_reg_offset(RING_PP_DIR_BASE(engine->mmio_base));
668 	*cs++ = pp_dir(vm);
669 
670 	/* Stall until the page table load is complete? */
671 	*cs++ = MI_STORE_REGISTER_MEM | MI_SRM_LRM_GLOBAL_GTT;
672 	*cs++ = i915_mmio_reg_offset(RING_PP_DIR_BASE(engine->mmio_base));
673 	*cs++ = intel_gt_scratch_offset(engine->gt,
674 					INTEL_GT_SCRATCH_FIELD_DEFAULT);
675 
676 	*cs++ = MI_LOAD_REGISTER_IMM(1);
677 	*cs++ = i915_mmio_reg_offset(RING_INSTPM(engine->mmio_base));
678 	*cs++ = _MASKED_BIT_ENABLE(INSTPM_TLB_INVALIDATE);
679 
680 	intel_ring_advance(rq, cs);
681 
682 	return rq->engine->emit_flush(rq, EMIT_FLUSH);
683 }
684 
685 static int mi_set_context(struct i915_request *rq,
686 			  struct intel_context *ce,
687 			  u32 flags)
688 {
689 	struct intel_engine_cs *engine = rq->engine;
690 	struct drm_i915_private *i915 = engine->i915;
691 	enum intel_engine_id id;
692 	const int num_engines =
693 		IS_HASWELL(i915) ? engine->gt->info.num_engines - 1 : 0;
694 	bool force_restore = false;
695 	int len;
696 	u32 *cs;
697 
698 	len = 4;
699 	if (GRAPHICS_VER(i915) == 7)
700 		len += 2 + (num_engines ? 4 * num_engines + 6 : 0);
701 	else if (GRAPHICS_VER(i915) == 5)
702 		len += 2;
703 	if (flags & MI_FORCE_RESTORE) {
704 		GEM_BUG_ON(flags & MI_RESTORE_INHIBIT);
705 		flags &= ~MI_FORCE_RESTORE;
706 		force_restore = true;
707 		len += 2;
708 	}
709 
710 	cs = intel_ring_begin(rq, len);
711 	if (IS_ERR(cs))
712 		return PTR_ERR(cs);
713 
714 	/* WaProgramMiArbOnOffAroundMiSetContext:ivb,vlv,hsw,bdw,chv */
715 	if (GRAPHICS_VER(i915) == 7) {
716 		*cs++ = MI_ARB_ON_OFF | MI_ARB_DISABLE;
717 		if (num_engines) {
718 			struct intel_engine_cs *signaller;
719 
720 			*cs++ = MI_LOAD_REGISTER_IMM(num_engines);
721 			for_each_engine(signaller, engine->gt, id) {
722 				if (signaller == engine)
723 					continue;
724 
725 				*cs++ = i915_mmio_reg_offset(
726 					   RING_PSMI_CTL(signaller->mmio_base));
727 				*cs++ = _MASKED_BIT_ENABLE(
728 						GEN6_PSMI_SLEEP_MSG_DISABLE);
729 			}
730 		}
731 	} else if (GRAPHICS_VER(i915) == 5) {
732 		/*
733 		 * This w/a is only listed for pre-production ilk a/b steppings,
734 		 * but is also mentioned for programming the powerctx. To be
735 		 * safe, just apply the workaround; we do not use SyncFlush so
736 		 * this should never take effect and so be a no-op!
737 		 */
738 		*cs++ = MI_SUSPEND_FLUSH | MI_SUSPEND_FLUSH_EN;
739 	}
740 
741 	if (force_restore) {
742 		/*
743 		 * The HW doesn't handle being told to restore the current
744 		 * context very well. Quite often it likes goes to go off and
745 		 * sulk, especially when it is meant to be reloading PP_DIR.
746 		 * A very simple fix to force the reload is to simply switch
747 		 * away from the current context and back again.
748 		 *
749 		 * Note that the kernel_context will contain random state
750 		 * following the INHIBIT_RESTORE. We accept this since we
751 		 * never use the kernel_context state; it is merely a
752 		 * placeholder we use to flush other contexts.
753 		 */
754 		*cs++ = MI_SET_CONTEXT;
755 		*cs++ = i915_ggtt_offset(engine->kernel_context->state) |
756 			MI_MM_SPACE_GTT |
757 			MI_RESTORE_INHIBIT;
758 	}
759 
760 	*cs++ = MI_NOOP;
761 	*cs++ = MI_SET_CONTEXT;
762 	*cs++ = i915_ggtt_offset(ce->state) | flags;
763 	/*
764 	 * w/a: MI_SET_CONTEXT must always be followed by MI_NOOP
765 	 * WaMiSetContext_Hang:snb,ivb,vlv
766 	 */
767 	*cs++ = MI_NOOP;
768 
769 	if (GRAPHICS_VER(i915) == 7) {
770 		if (num_engines) {
771 			struct intel_engine_cs *signaller;
772 			i915_reg_t last_reg = INVALID_MMIO_REG; /* keep gcc quiet */
773 
774 			*cs++ = MI_LOAD_REGISTER_IMM(num_engines);
775 			for_each_engine(signaller, engine->gt, id) {
776 				if (signaller == engine)
777 					continue;
778 
779 				last_reg = RING_PSMI_CTL(signaller->mmio_base);
780 				*cs++ = i915_mmio_reg_offset(last_reg);
781 				*cs++ = _MASKED_BIT_DISABLE(
782 						GEN6_PSMI_SLEEP_MSG_DISABLE);
783 			}
784 
785 			/* Insert a delay before the next switch! */
786 			*cs++ = MI_STORE_REGISTER_MEM | MI_SRM_LRM_GLOBAL_GTT;
787 			*cs++ = i915_mmio_reg_offset(last_reg);
788 			*cs++ = intel_gt_scratch_offset(engine->gt,
789 							INTEL_GT_SCRATCH_FIELD_DEFAULT);
790 			*cs++ = MI_NOOP;
791 		}
792 		*cs++ = MI_ARB_ON_OFF | MI_ARB_ENABLE;
793 	} else if (GRAPHICS_VER(i915) == 5) {
794 		*cs++ = MI_SUSPEND_FLUSH;
795 	}
796 
797 	intel_ring_advance(rq, cs);
798 
799 	return 0;
800 }
801 
802 static int remap_l3_slice(struct i915_request *rq, int slice)
803 {
804 #define L3LOG_DW (GEN7_L3LOG_SIZE / sizeof(u32))
805 	u32 *cs, *remap_info = rq->engine->i915->l3_parity.remap_info[slice];
806 	int i;
807 
808 	if (!remap_info)
809 		return 0;
810 
811 	cs = intel_ring_begin(rq, L3LOG_DW * 2 + 2);
812 	if (IS_ERR(cs))
813 		return PTR_ERR(cs);
814 
815 	/*
816 	 * Note: We do not worry about the concurrent register cacheline hang
817 	 * here because no other code should access these registers other than
818 	 * at initialization time.
819 	 */
820 	*cs++ = MI_LOAD_REGISTER_IMM(L3LOG_DW);
821 	for (i = 0; i < L3LOG_DW; i++) {
822 		*cs++ = i915_mmio_reg_offset(GEN7_L3LOG(slice, i));
823 		*cs++ = remap_info[i];
824 	}
825 	*cs++ = MI_NOOP;
826 	intel_ring_advance(rq, cs);
827 
828 	return 0;
829 #undef L3LOG_DW
830 }
831 
832 static int remap_l3(struct i915_request *rq)
833 {
834 	struct i915_gem_context *ctx = i915_request_gem_context(rq);
835 	int i, err;
836 
837 	if (!ctx || !ctx->remap_slice)
838 		return 0;
839 
840 	for (i = 0; i < MAX_L3_SLICES; i++) {
841 		if (!(ctx->remap_slice & BIT(i)))
842 			continue;
843 
844 		err = remap_l3_slice(rq, i);
845 		if (err)
846 			return err;
847 	}
848 
849 	ctx->remap_slice = 0;
850 	return 0;
851 }
852 
853 static int switch_mm(struct i915_request *rq, struct i915_address_space *vm)
854 {
855 	int ret;
856 
857 	if (!vm)
858 		return 0;
859 
860 	ret = rq->engine->emit_flush(rq, EMIT_FLUSH);
861 	if (ret)
862 		return ret;
863 
864 	/*
865 	 * Not only do we need a full barrier (post-sync write) after
866 	 * invalidating the TLBs, but we need to wait a little bit
867 	 * longer. Whether this is merely delaying us, or the
868 	 * subsequent flush is a key part of serialising with the
869 	 * post-sync op, this extra pass appears vital before a
870 	 * mm switch!
871 	 */
872 	ret = load_pd_dir(rq, vm, PP_DIR_DCLV_2G);
873 	if (ret)
874 		return ret;
875 
876 	return rq->engine->emit_flush(rq, EMIT_INVALIDATE);
877 }
878 
879 static int clear_residuals(struct i915_request *rq)
880 {
881 	struct intel_engine_cs *engine = rq->engine;
882 	int ret;
883 
884 	ret = switch_mm(rq, vm_alias(engine->kernel_context->vm));
885 	if (ret)
886 		return ret;
887 
888 	if (engine->kernel_context->state) {
889 		ret = mi_set_context(rq,
890 				     engine->kernel_context,
891 				     MI_MM_SPACE_GTT | MI_RESTORE_INHIBIT);
892 		if (ret)
893 			return ret;
894 	}
895 
896 	ret = engine->emit_bb_start(rq,
897 				    engine->wa_ctx.vma->node.start, 0,
898 				    0);
899 	if (ret)
900 		return ret;
901 
902 	ret = engine->emit_flush(rq, EMIT_FLUSH);
903 	if (ret)
904 		return ret;
905 
906 	/* Always invalidate before the next switch_mm() */
907 	return engine->emit_flush(rq, EMIT_INVALIDATE);
908 }
909 
910 static int switch_context(struct i915_request *rq)
911 {
912 	struct intel_engine_cs *engine = rq->engine;
913 	struct intel_context *ce = rq->context;
914 	void **residuals = NULL;
915 	int ret;
916 
917 	GEM_BUG_ON(HAS_EXECLISTS(engine->i915));
918 
919 	if (engine->wa_ctx.vma && ce != engine->kernel_context) {
920 		if (engine->wa_ctx.vma->private != ce &&
921 		    i915_mitigate_clear_residuals()) {
922 			ret = clear_residuals(rq);
923 			if (ret)
924 				return ret;
925 
926 			residuals = &engine->wa_ctx.vma->private;
927 		}
928 	}
929 
930 	ret = switch_mm(rq, vm_alias(ce->vm));
931 	if (ret)
932 		return ret;
933 
934 	if (ce->state) {
935 		u32 flags;
936 
937 		GEM_BUG_ON(engine->id != RCS0);
938 
939 		/* For resource streamer on HSW+ and power context elsewhere */
940 		BUILD_BUG_ON(HSW_MI_RS_SAVE_STATE_EN != MI_SAVE_EXT_STATE_EN);
941 		BUILD_BUG_ON(HSW_MI_RS_RESTORE_STATE_EN != MI_RESTORE_EXT_STATE_EN);
942 
943 		flags = MI_SAVE_EXT_STATE_EN | MI_MM_SPACE_GTT;
944 		if (test_bit(CONTEXT_VALID_BIT, &ce->flags))
945 			flags |= MI_RESTORE_EXT_STATE_EN;
946 		else
947 			flags |= MI_RESTORE_INHIBIT;
948 
949 		ret = mi_set_context(rq, ce, flags);
950 		if (ret)
951 			return ret;
952 	}
953 
954 	ret = remap_l3(rq);
955 	if (ret)
956 		return ret;
957 
958 	/*
959 	 * Now past the point of no return, this request _will_ be emitted.
960 	 *
961 	 * Or at least this preamble will be emitted, the request may be
962 	 * interrupted prior to submitting the user payload. If so, we
963 	 * still submit the "empty" request in order to preserve global
964 	 * state tracking such as this, our tracking of the current
965 	 * dirty context.
966 	 */
967 	if (residuals) {
968 		intel_context_put(*residuals);
969 		*residuals = intel_context_get(ce);
970 	}
971 
972 	return 0;
973 }
974 
975 static int ring_request_alloc(struct i915_request *request)
976 {
977 	int ret;
978 
979 	GEM_BUG_ON(!intel_context_is_pinned(request->context));
980 	GEM_BUG_ON(i915_request_timeline(request)->has_initial_breadcrumb);
981 
982 	/*
983 	 * Flush enough space to reduce the likelihood of waiting after
984 	 * we start building the request - in which case we will just
985 	 * have to repeat work.
986 	 */
987 	request->reserved_space += LEGACY_REQUEST_SIZE;
988 
989 	/* Unconditionally invalidate GPU caches and TLBs. */
990 	ret = request->engine->emit_flush(request, EMIT_INVALIDATE);
991 	if (ret)
992 		return ret;
993 
994 	ret = switch_context(request);
995 	if (ret)
996 		return ret;
997 
998 	request->reserved_space -= LEGACY_REQUEST_SIZE;
999 	return 0;
1000 }
1001 
1002 static void gen6_bsd_submit_request(struct i915_request *request)
1003 {
1004 	struct intel_uncore *uncore = request->engine->uncore;
1005 
1006 	intel_uncore_forcewake_get(uncore, FORCEWAKE_ALL);
1007 
1008        /* Every tail move must follow the sequence below */
1009 
1010 	/* Disable notification that the ring is IDLE. The GT
1011 	 * will then assume that it is busy and bring it out of rc6.
1012 	 */
1013 	intel_uncore_write_fw(uncore, RING_PSMI_CTL(GEN6_BSD_RING_BASE),
1014 			      _MASKED_BIT_ENABLE(GEN6_PSMI_SLEEP_MSG_DISABLE));
1015 
1016 	/* Clear the context id. Here be magic! */
1017 	intel_uncore_write64_fw(uncore, GEN6_BSD_RNCID, 0x0);
1018 
1019 	/* Wait for the ring not to be idle, i.e. for it to wake up. */
1020 	if (__intel_wait_for_register_fw(uncore,
1021 					 RING_PSMI_CTL(GEN6_BSD_RING_BASE),
1022 					 GEN6_BSD_SLEEP_INDICATOR,
1023 					 0,
1024 					 1000, 0, NULL))
1025 		drm_err(&uncore->i915->drm,
1026 			"timed out waiting for the BSD ring to wake up\n");
1027 
1028 	/* Now that the ring is fully powered up, update the tail */
1029 	i9xx_submit_request(request);
1030 
1031 	/* Let the ring send IDLE messages to the GT again,
1032 	 * and so let it sleep to conserve power when idle.
1033 	 */
1034 	intel_uncore_write_fw(uncore, RING_PSMI_CTL(GEN6_BSD_RING_BASE),
1035 			      _MASKED_BIT_DISABLE(GEN6_PSMI_SLEEP_MSG_DISABLE));
1036 
1037 	intel_uncore_forcewake_put(uncore, FORCEWAKE_ALL);
1038 }
1039 
1040 static void i9xx_set_default_submission(struct intel_engine_cs *engine)
1041 {
1042 	engine->submit_request = i9xx_submit_request;
1043 }
1044 
1045 static void gen6_bsd_set_default_submission(struct intel_engine_cs *engine)
1046 {
1047 	engine->submit_request = gen6_bsd_submit_request;
1048 }
1049 
1050 static void ring_release(struct intel_engine_cs *engine)
1051 {
1052 	struct drm_i915_private *dev_priv = engine->i915;
1053 
1054 	drm_WARN_ON(&dev_priv->drm, GRAPHICS_VER(dev_priv) > 2 &&
1055 		    (ENGINE_READ(engine, RING_MI_MODE) & MODE_IDLE) == 0);
1056 
1057 	intel_engine_cleanup_common(engine);
1058 
1059 	if (engine->wa_ctx.vma) {
1060 		intel_context_put(engine->wa_ctx.vma->private);
1061 		i915_vma_unpin_and_release(&engine->wa_ctx.vma, 0);
1062 	}
1063 
1064 	intel_ring_unpin(engine->legacy.ring);
1065 	intel_ring_put(engine->legacy.ring);
1066 
1067 	intel_timeline_unpin(engine->legacy.timeline);
1068 	intel_timeline_put(engine->legacy.timeline);
1069 }
1070 
1071 static void irq_handler(struct intel_engine_cs *engine, u16 iir)
1072 {
1073 	intel_engine_signal_breadcrumbs(engine);
1074 }
1075 
1076 static void setup_irq(struct intel_engine_cs *engine)
1077 {
1078 	struct drm_i915_private *i915 = engine->i915;
1079 
1080 	intel_engine_set_irq_handler(engine, irq_handler);
1081 
1082 	if (GRAPHICS_VER(i915) >= 6) {
1083 		engine->irq_enable = gen6_irq_enable;
1084 		engine->irq_disable = gen6_irq_disable;
1085 	} else if (GRAPHICS_VER(i915) >= 5) {
1086 		engine->irq_enable = gen5_irq_enable;
1087 		engine->irq_disable = gen5_irq_disable;
1088 	} else if (GRAPHICS_VER(i915) >= 3) {
1089 		engine->irq_enable = gen3_irq_enable;
1090 		engine->irq_disable = gen3_irq_disable;
1091 	} else {
1092 		engine->irq_enable = gen2_irq_enable;
1093 		engine->irq_disable = gen2_irq_disable;
1094 	}
1095 }
1096 
1097 static void add_to_engine(struct i915_request *rq)
1098 {
1099 	lockdep_assert_held(&rq->engine->sched_engine->lock);
1100 	list_move_tail(&rq->sched.link, &rq->engine->sched_engine->requests);
1101 }
1102 
1103 static void remove_from_engine(struct i915_request *rq)
1104 {
1105 	spin_lock_irq(&rq->engine->sched_engine->lock);
1106 	list_del_init(&rq->sched.link);
1107 
1108 	/* Prevent further __await_execution() registering a cb, then flush */
1109 	set_bit(I915_FENCE_FLAG_ACTIVE, &rq->fence.flags);
1110 
1111 	spin_unlock_irq(&rq->engine->sched_engine->lock);
1112 
1113 	i915_request_notify_execute_cb_imm(rq);
1114 }
1115 
1116 static void setup_common(struct intel_engine_cs *engine)
1117 {
1118 	struct drm_i915_private *i915 = engine->i915;
1119 
1120 	/* gen8+ are only supported with execlists */
1121 	GEM_BUG_ON(GRAPHICS_VER(i915) >= 8);
1122 
1123 	setup_irq(engine);
1124 
1125 	engine->resume = xcs_resume;
1126 	engine->sanitize = xcs_sanitize;
1127 
1128 	engine->reset.prepare = reset_prepare;
1129 	engine->reset.rewind = reset_rewind;
1130 	engine->reset.cancel = reset_cancel;
1131 	engine->reset.finish = reset_finish;
1132 
1133 	engine->add_active_request = add_to_engine;
1134 	engine->remove_active_request = remove_from_engine;
1135 
1136 	engine->cops = &ring_context_ops;
1137 	engine->request_alloc = ring_request_alloc;
1138 
1139 	/*
1140 	 * Using a global execution timeline; the previous final breadcrumb is
1141 	 * equivalent to our next initial bread so we can elide
1142 	 * engine->emit_init_breadcrumb().
1143 	 */
1144 	engine->emit_fini_breadcrumb = gen3_emit_breadcrumb;
1145 	if (GRAPHICS_VER(i915) == 5)
1146 		engine->emit_fini_breadcrumb = gen5_emit_breadcrumb;
1147 
1148 	engine->set_default_submission = i9xx_set_default_submission;
1149 
1150 	if (GRAPHICS_VER(i915) >= 6)
1151 		engine->emit_bb_start = gen6_emit_bb_start;
1152 	else if (GRAPHICS_VER(i915) >= 4)
1153 		engine->emit_bb_start = gen4_emit_bb_start;
1154 	else if (IS_I830(i915) || IS_I845G(i915))
1155 		engine->emit_bb_start = i830_emit_bb_start;
1156 	else
1157 		engine->emit_bb_start = gen3_emit_bb_start;
1158 }
1159 
1160 static void setup_rcs(struct intel_engine_cs *engine)
1161 {
1162 	struct drm_i915_private *i915 = engine->i915;
1163 
1164 	if (HAS_L3_DPF(i915))
1165 		engine->irq_keep_mask = GT_RENDER_L3_PARITY_ERROR_INTERRUPT;
1166 
1167 	engine->irq_enable_mask = GT_RENDER_USER_INTERRUPT;
1168 
1169 	if (GRAPHICS_VER(i915) >= 7) {
1170 		engine->emit_flush = gen7_emit_flush_rcs;
1171 		engine->emit_fini_breadcrumb = gen7_emit_breadcrumb_rcs;
1172 	} else if (GRAPHICS_VER(i915) == 6) {
1173 		engine->emit_flush = gen6_emit_flush_rcs;
1174 		engine->emit_fini_breadcrumb = gen6_emit_breadcrumb_rcs;
1175 	} else if (GRAPHICS_VER(i915) == 5) {
1176 		engine->emit_flush = gen4_emit_flush_rcs;
1177 	} else {
1178 		if (GRAPHICS_VER(i915) < 4)
1179 			engine->emit_flush = gen2_emit_flush;
1180 		else
1181 			engine->emit_flush = gen4_emit_flush_rcs;
1182 		engine->irq_enable_mask = I915_USER_INTERRUPT;
1183 	}
1184 
1185 	if (IS_HASWELL(i915))
1186 		engine->emit_bb_start = hsw_emit_bb_start;
1187 }
1188 
1189 static void setup_vcs(struct intel_engine_cs *engine)
1190 {
1191 	struct drm_i915_private *i915 = engine->i915;
1192 
1193 	if (GRAPHICS_VER(i915) >= 6) {
1194 		/* gen6 bsd needs a special wa for tail updates */
1195 		if (GRAPHICS_VER(i915) == 6)
1196 			engine->set_default_submission = gen6_bsd_set_default_submission;
1197 		engine->emit_flush = gen6_emit_flush_vcs;
1198 		engine->irq_enable_mask = GT_BSD_USER_INTERRUPT;
1199 
1200 		if (GRAPHICS_VER(i915) == 6)
1201 			engine->emit_fini_breadcrumb = gen6_emit_breadcrumb_xcs;
1202 		else
1203 			engine->emit_fini_breadcrumb = gen7_emit_breadcrumb_xcs;
1204 	} else {
1205 		engine->emit_flush = gen4_emit_flush_vcs;
1206 		if (GRAPHICS_VER(i915) == 5)
1207 			engine->irq_enable_mask = ILK_BSD_USER_INTERRUPT;
1208 		else
1209 			engine->irq_enable_mask = I915_BSD_USER_INTERRUPT;
1210 	}
1211 }
1212 
1213 static void setup_bcs(struct intel_engine_cs *engine)
1214 {
1215 	struct drm_i915_private *i915 = engine->i915;
1216 
1217 	engine->emit_flush = gen6_emit_flush_xcs;
1218 	engine->irq_enable_mask = GT_BLT_USER_INTERRUPT;
1219 
1220 	if (GRAPHICS_VER(i915) == 6)
1221 		engine->emit_fini_breadcrumb = gen6_emit_breadcrumb_xcs;
1222 	else
1223 		engine->emit_fini_breadcrumb = gen7_emit_breadcrumb_xcs;
1224 }
1225 
1226 static void setup_vecs(struct intel_engine_cs *engine)
1227 {
1228 	struct drm_i915_private *i915 = engine->i915;
1229 
1230 	GEM_BUG_ON(GRAPHICS_VER(i915) < 7);
1231 
1232 	engine->emit_flush = gen6_emit_flush_xcs;
1233 	engine->irq_enable_mask = PM_VEBOX_USER_INTERRUPT;
1234 	engine->irq_enable = hsw_irq_enable_vecs;
1235 	engine->irq_disable = hsw_irq_disable_vecs;
1236 
1237 	engine->emit_fini_breadcrumb = gen7_emit_breadcrumb_xcs;
1238 }
1239 
1240 static int gen7_ctx_switch_bb_setup(struct intel_engine_cs * const engine,
1241 				    struct i915_vma * const vma)
1242 {
1243 	return gen7_setup_clear_gpr_bb(engine, vma);
1244 }
1245 
1246 static int gen7_ctx_switch_bb_init(struct intel_engine_cs *engine,
1247 				   struct i915_gem_ww_ctx *ww,
1248 				   struct i915_vma *vma)
1249 {
1250 	int err;
1251 
1252 	err = i915_vma_pin_ww(vma, ww, 0, 0, PIN_USER | PIN_HIGH);
1253 	if (err)
1254 		return err;
1255 
1256 	err = i915_vma_sync(vma);
1257 	if (err)
1258 		goto err_unpin;
1259 
1260 	err = gen7_ctx_switch_bb_setup(engine, vma);
1261 	if (err)
1262 		goto err_unpin;
1263 
1264 	engine->wa_ctx.vma = vma;
1265 	return 0;
1266 
1267 err_unpin:
1268 	i915_vma_unpin(vma);
1269 	return err;
1270 }
1271 
1272 static struct i915_vma *gen7_ctx_vma(struct intel_engine_cs *engine)
1273 {
1274 	struct drm_i915_gem_object *obj;
1275 	struct i915_vma *vma;
1276 	int size, err;
1277 
1278 	if (GRAPHICS_VER(engine->i915) != 7 || engine->class != RENDER_CLASS)
1279 		return NULL;
1280 
1281 	err = gen7_ctx_switch_bb_setup(engine, NULL /* probe size */);
1282 	if (err < 0)
1283 		return ERR_PTR(err);
1284 	if (!err)
1285 		return NULL;
1286 
1287 	size = ALIGN(err, PAGE_SIZE);
1288 
1289 	obj = i915_gem_object_create_internal(engine->i915, size);
1290 	if (IS_ERR(obj))
1291 		return ERR_CAST(obj);
1292 
1293 	vma = i915_vma_instance(obj, engine->gt->vm, NULL);
1294 	if (IS_ERR(vma)) {
1295 		i915_gem_object_put(obj);
1296 		return ERR_CAST(vma);
1297 	}
1298 
1299 	vma->private = intel_context_create(engine); /* dummy residuals */
1300 	if (IS_ERR(vma->private)) {
1301 		err = PTR_ERR(vma->private);
1302 		vma->private = NULL;
1303 		i915_gem_object_put(obj);
1304 		return ERR_PTR(err);
1305 	}
1306 
1307 	return vma;
1308 }
1309 
1310 int intel_ring_submission_setup(struct intel_engine_cs *engine)
1311 {
1312 	struct i915_gem_ww_ctx ww;
1313 	struct intel_timeline *timeline;
1314 	struct intel_ring *ring;
1315 	struct i915_vma *gen7_wa_vma;
1316 	int err;
1317 
1318 	setup_common(engine);
1319 
1320 	switch (engine->class) {
1321 	case RENDER_CLASS:
1322 		setup_rcs(engine);
1323 		break;
1324 	case VIDEO_DECODE_CLASS:
1325 		setup_vcs(engine);
1326 		break;
1327 	case COPY_ENGINE_CLASS:
1328 		setup_bcs(engine);
1329 		break;
1330 	case VIDEO_ENHANCEMENT_CLASS:
1331 		setup_vecs(engine);
1332 		break;
1333 	default:
1334 		MISSING_CASE(engine->class);
1335 		return -ENODEV;
1336 	}
1337 
1338 	timeline = intel_timeline_create_from_engine(engine,
1339 						     I915_GEM_HWS_SEQNO_ADDR);
1340 	if (IS_ERR(timeline)) {
1341 		err = PTR_ERR(timeline);
1342 		goto err;
1343 	}
1344 	GEM_BUG_ON(timeline->has_initial_breadcrumb);
1345 
1346 	ring = intel_engine_create_ring(engine, SZ_16K);
1347 	if (IS_ERR(ring)) {
1348 		err = PTR_ERR(ring);
1349 		goto err_timeline;
1350 	}
1351 
1352 	GEM_BUG_ON(engine->legacy.ring);
1353 	engine->legacy.ring = ring;
1354 	engine->legacy.timeline = timeline;
1355 
1356 	gen7_wa_vma = gen7_ctx_vma(engine);
1357 	if (IS_ERR(gen7_wa_vma)) {
1358 		err = PTR_ERR(gen7_wa_vma);
1359 		goto err_ring;
1360 	}
1361 
1362 	i915_gem_ww_ctx_init(&ww, false);
1363 
1364 retry:
1365 	err = i915_gem_object_lock(timeline->hwsp_ggtt->obj, &ww);
1366 	if (!err && gen7_wa_vma)
1367 		err = i915_gem_object_lock(gen7_wa_vma->obj, &ww);
1368 	if (!err)
1369 		err = i915_gem_object_lock(engine->legacy.ring->vma->obj, &ww);
1370 	if (!err)
1371 		err = intel_timeline_pin(timeline, &ww);
1372 	if (!err) {
1373 		err = intel_ring_pin(ring, &ww);
1374 		if (err)
1375 			intel_timeline_unpin(timeline);
1376 	}
1377 	if (err)
1378 		goto out;
1379 
1380 	GEM_BUG_ON(timeline->hwsp_ggtt != engine->status_page.vma);
1381 
1382 	if (gen7_wa_vma) {
1383 		err = gen7_ctx_switch_bb_init(engine, &ww, gen7_wa_vma);
1384 		if (err) {
1385 			intel_ring_unpin(ring);
1386 			intel_timeline_unpin(timeline);
1387 		}
1388 	}
1389 
1390 out:
1391 	if (err == -EDEADLK) {
1392 		err = i915_gem_ww_ctx_backoff(&ww);
1393 		if (!err)
1394 			goto retry;
1395 	}
1396 	i915_gem_ww_ctx_fini(&ww);
1397 	if (err)
1398 		goto err_gen7_put;
1399 
1400 	/* Finally, take ownership and responsibility for cleanup! */
1401 	engine->release = ring_release;
1402 
1403 	return 0;
1404 
1405 err_gen7_put:
1406 	if (gen7_wa_vma) {
1407 		intel_context_put(gen7_wa_vma->private);
1408 		i915_gem_object_put(gen7_wa_vma->obj);
1409 	}
1410 err_ring:
1411 	intel_ring_put(ring);
1412 err_timeline:
1413 	intel_timeline_put(timeline);
1414 err:
1415 	intel_engine_cleanup_common(engine);
1416 	return err;
1417 }
1418 
1419 #if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
1420 #include "selftest_ring_submission.c"
1421 #endif
1422