1 /*
2  * Copyright © 2014 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  */
24 #include <linux/firmware.h>
25 #include <linux/circ_buf.h>
26 #include "i915_drv.h"
27 #include "intel_guc.h"
28 
29 /**
30  * DOC: GuC-based command submission
31  *
32  * i915_guc_client:
33  * We use the term client to avoid confusion with contexts. A i915_guc_client is
34  * equivalent to GuC object guc_context_desc. This context descriptor is
35  * allocated from a pool of 1024 entries. Kernel driver will allocate doorbell
36  * and workqueue for it. Also the process descriptor (guc_process_desc), which
37  * is mapped to client space. So the client can write Work Item then ring the
38  * doorbell.
39  *
40  * To simplify the implementation, we allocate one gem object that contains all
41  * pages for doorbell, process descriptor and workqueue.
42  *
43  * The Scratch registers:
44  * There are 16 MMIO-based registers start from 0xC180. The kernel driver writes
45  * a value to the action register (SOFT_SCRATCH_0) along with any data. It then
46  * triggers an interrupt on the GuC via another register write (0xC4C8).
47  * Firmware writes a success/fail code back to the action register after
48  * processes the request. The kernel driver polls waiting for this update and
49  * then proceeds.
50  * See host2guc_action()
51  *
52  * Doorbells:
53  * Doorbells are interrupts to uKernel. A doorbell is a single cache line (QW)
54  * mapped into process space.
55  *
56  * Work Items:
57  * There are several types of work items that the host may place into a
58  * workqueue, each with its own requirements and limitations. Currently only
59  * WQ_TYPE_INORDER is needed to support legacy submission via GuC, which
60  * represents in-order queue. The kernel driver packs ring tail pointer and an
61  * ELSP context descriptor dword into Work Item.
62  * See guc_add_workqueue_item()
63  *
64  */
65 
66 /*
67  * Read GuC command/status register (SOFT_SCRATCH_0)
68  * Return true if it contains a response rather than a command
69  */
70 static inline bool host2guc_action_response(struct drm_i915_private *dev_priv,
71 					    u32 *status)
72 {
73 	u32 val = I915_READ(SOFT_SCRATCH(0));
74 	*status = val;
75 	return GUC2HOST_IS_RESPONSE(val);
76 }
77 
78 static int host2guc_action(struct intel_guc *guc, u32 *data, u32 len)
79 {
80 	struct drm_i915_private *dev_priv = guc_to_i915(guc);
81 	u32 status;
82 	int i;
83 	int ret;
84 
85 	if (WARN_ON(len < 1 || len > 15))
86 		return -EINVAL;
87 
88 	intel_uncore_forcewake_get(dev_priv, FORCEWAKE_ALL);
89 
90 	dev_priv->guc.action_count += 1;
91 	dev_priv->guc.action_cmd = data[0];
92 
93 	for (i = 0; i < len; i++)
94 		I915_WRITE(SOFT_SCRATCH(i), data[i]);
95 
96 	POSTING_READ(SOFT_SCRATCH(i - 1));
97 
98 	I915_WRITE(HOST2GUC_INTERRUPT, HOST2GUC_TRIGGER);
99 
100 	/* No HOST2GUC command should take longer than 10ms */
101 	ret = wait_for_atomic(host2guc_action_response(dev_priv, &status), 10);
102 	if (status != GUC2HOST_STATUS_SUCCESS) {
103 		/*
104 		 * Either the GuC explicitly returned an error (which
105 		 * we convert to -EIO here) or no response at all was
106 		 * received within the timeout limit (-ETIMEDOUT)
107 		 */
108 		if (ret != -ETIMEDOUT)
109 			ret = -EIO;
110 
111 		DRM_ERROR("GUC: host2guc action 0x%X failed. ret=%d "
112 				"status=0x%08X response=0x%08X\n",
113 				data[0], ret, status,
114 				I915_READ(SOFT_SCRATCH(15)));
115 
116 		dev_priv->guc.action_fail += 1;
117 		dev_priv->guc.action_err = ret;
118 	}
119 	dev_priv->guc.action_status = status;
120 
121 	intel_uncore_forcewake_put(dev_priv, FORCEWAKE_ALL);
122 
123 	return ret;
124 }
125 
126 /*
127  * Tell the GuC to allocate or deallocate a specific doorbell
128  */
129 
130 static int host2guc_allocate_doorbell(struct intel_guc *guc,
131 				      struct i915_guc_client *client)
132 {
133 	u32 data[2];
134 
135 	data[0] = HOST2GUC_ACTION_ALLOCATE_DOORBELL;
136 	data[1] = client->ctx_index;
137 
138 	return host2guc_action(guc, data, 2);
139 }
140 
141 static int host2guc_release_doorbell(struct intel_guc *guc,
142 				     struct i915_guc_client *client)
143 {
144 	u32 data[2];
145 
146 	data[0] = HOST2GUC_ACTION_DEALLOCATE_DOORBELL;
147 	data[1] = client->ctx_index;
148 
149 	return host2guc_action(guc, data, 2);
150 }
151 
152 static int host2guc_sample_forcewake(struct intel_guc *guc,
153 				     struct i915_guc_client *client)
154 {
155 	struct drm_i915_private *dev_priv = guc_to_i915(guc);
156 	struct drm_device *dev = dev_priv->dev;
157 	u32 data[2];
158 
159 	data[0] = HOST2GUC_ACTION_SAMPLE_FORCEWAKE;
160 	/* WaRsDisableCoarsePowerGating:skl,bxt */
161 	if (!intel_enable_rc6(dev) ||
162 	    NEEDS_WaRsDisableCoarsePowerGating(dev))
163 		data[1] = 0;
164 	else
165 		/* bit 0 and 1 are for Render and Media domain separately */
166 		data[1] = GUC_FORCEWAKE_RENDER | GUC_FORCEWAKE_MEDIA;
167 
168 	return host2guc_action(guc, data, ARRAY_SIZE(data));
169 }
170 
171 /*
172  * Initialise, update, or clear doorbell data shared with the GuC
173  *
174  * These functions modify shared data and so need access to the mapped
175  * client object which contains the page being used for the doorbell
176  */
177 
178 static void guc_init_doorbell(struct intel_guc *guc,
179 			      struct i915_guc_client *client)
180 {
181 	struct guc_doorbell_info *doorbell;
182 
183 	doorbell = (struct guc_doorbell_info *)((char *)client->client_base + client->doorbell_offset);
184 
185 	doorbell->db_status = GUC_DOORBELL_ENABLED;
186 	doorbell->cookie = 0;
187 }
188 
189 static int guc_ring_doorbell(struct i915_guc_client *gc)
190 {
191 	struct guc_process_desc *desc;
192 	union guc_doorbell_qw db_cmp, db_exc, db_ret;
193 	union guc_doorbell_qw *db;
194 	int attempt = 2, ret = -EAGAIN;
195 
196 	desc = (struct guc_process_desc *)((char *)gc->client_base + gc->proc_desc_offset);
197 
198 	/* Update the tail so it is visible to GuC */
199 	desc->tail = gc->wq_tail;
200 
201 	/* current cookie */
202 	db_cmp.db_status = GUC_DOORBELL_ENABLED;
203 	db_cmp.cookie = gc->cookie;
204 
205 	/* cookie to be updated */
206 	db_exc.db_status = GUC_DOORBELL_ENABLED;
207 	db_exc.cookie = gc->cookie + 1;
208 	if (db_exc.cookie == 0)
209 		db_exc.cookie = 1;
210 
211 	/* pointer of current doorbell cacheline */
212 	db = (union guc_doorbell_qw *)((char *)gc->client_base + gc->doorbell_offset);
213 
214 	while (attempt--) {
215 		/* lets ring the doorbell */
216 		db_ret.value_qw = atomic64_cmpxchg((atomic64_t *)db,
217 			db_cmp.value_qw, db_exc.value_qw);
218 
219 		/* if the exchange was successfully executed */
220 		if (db_ret.value_qw == db_cmp.value_qw) {
221 			/* db was successfully rung */
222 			gc->cookie = db_exc.cookie;
223 			ret = 0;
224 			break;
225 		}
226 
227 		/* XXX: doorbell was lost and need to acquire it again */
228 		if (db_ret.db_status == GUC_DOORBELL_DISABLED)
229 			break;
230 
231 		DRM_ERROR("Cookie mismatch. Expected %d, returned %d\n",
232 			  db_cmp.cookie, db_ret.cookie);
233 
234 		/* update the cookie to newly read cookie from GuC */
235 		db_cmp.cookie = db_ret.cookie;
236 		db_exc.cookie = db_ret.cookie + 1;
237 		if (db_exc.cookie == 0)
238 			db_exc.cookie = 1;
239 	}
240 
241 	return ret;
242 }
243 
244 static void guc_disable_doorbell(struct intel_guc *guc,
245 				 struct i915_guc_client *client)
246 {
247 	struct drm_i915_private *dev_priv = guc_to_i915(guc);
248 	struct guc_doorbell_info *doorbell;
249 	i915_reg_t drbreg = GEN8_DRBREGL(client->doorbell_id);
250 	int value;
251 
252 	doorbell = (struct guc_doorbell_info*)((char *)client->client_base + client->doorbell_offset);
253 
254 	doorbell->db_status = GUC_DOORBELL_DISABLED;
255 
256 	I915_WRITE(drbreg, I915_READ(drbreg) & ~GEN8_DRB_VALID);
257 
258 	value = I915_READ(drbreg);
259 	WARN_ON((value & GEN8_DRB_VALID) != 0);
260 
261 	I915_WRITE(GEN8_DRBREGU(client->doorbell_id), 0);
262 	I915_WRITE(drbreg, 0);
263 
264 	/* XXX: wait for any interrupts */
265 	/* XXX: wait for workqueue to drain */
266 }
267 
268 /*
269  * Select, assign and relase doorbell cachelines
270  *
271  * These functions track which doorbell cachelines are in use.
272  * The data they manipulate is protected by the host2guc lock.
273  */
274 
275 static uint32_t select_doorbell_cacheline(struct intel_guc *guc)
276 {
277 	const uint32_t cacheline_size = cache_line_size();
278 	uint32_t offset;
279 
280 	/* Doorbell uses a single cache line within a page */
281 	offset = offset_in_page(guc->db_cacheline);
282 
283 	/* Moving to next cache line to reduce contention */
284 	guc->db_cacheline += cacheline_size;
285 
286 	DRM_DEBUG_DRIVER("selected doorbell cacheline 0x%x, next 0x%x, linesize %u\n",
287 			offset, guc->db_cacheline, cacheline_size);
288 
289 	return offset;
290 }
291 
292 static uint16_t assign_doorbell(struct intel_guc *guc, uint32_t priority)
293 {
294 	/*
295 	 * The bitmap is split into two halves; the first half is used for
296 	 * normal priority contexts, the second half for high-priority ones.
297 	 * Note that logically higher priorities are numerically less than
298 	 * normal ones, so the test below means "is it high-priority?"
299 	 */
300 	const bool hi_pri = (priority <= GUC_CTX_PRIORITY_HIGH);
301 	const uint16_t half = GUC_MAX_DOORBELLS / 2;
302 	const uint16_t start = hi_pri ? half : 0;
303 	const uint16_t end = start + half;
304 	uint16_t id;
305 
306 	id = find_next_zero_bit(guc->doorbell_bitmap, end, start);
307 	if (id == end)
308 		id = GUC_INVALID_DOORBELL_ID;
309 	else
310 		bitmap_set(guc->doorbell_bitmap, id, 1);
311 
312 	DRM_DEBUG_DRIVER("assigned %s priority doorbell id 0x%x\n",
313 			hi_pri ? "high" : "normal", id);
314 
315 	return id;
316 }
317 
318 static void release_doorbell(struct intel_guc *guc, uint16_t id)
319 {
320 	bitmap_clear(guc->doorbell_bitmap, id, 1);
321 }
322 
323 /*
324  * Initialise the process descriptor shared with the GuC firmware.
325  */
326 static void guc_init_proc_desc(struct intel_guc *guc,
327 			       struct i915_guc_client *client)
328 {
329 	struct guc_process_desc *desc;
330 
331 	desc = (struct guc_process_desc *)((char *)client->client_base + client->proc_desc_offset);
332 
333 	memset(desc, 0, sizeof(*desc));
334 
335 	/*
336 	 * XXX: pDoorbell and WQVBaseAddress are pointers in process address
337 	 * space for ring3 clients (set them as in mmap_ioctl) or kernel
338 	 * space for kernel clients (map on demand instead? May make debug
339 	 * easier to have it mapped).
340 	 */
341 	desc->wq_base_addr = 0;
342 	desc->db_base_addr = 0;
343 
344 	desc->context_id = client->ctx_index;
345 	desc->wq_size_bytes = client->wq_size;
346 	desc->wq_status = WQ_STATUS_ACTIVE;
347 	desc->priority = client->priority;
348 }
349 
350 /*
351  * Initialise/clear the context descriptor shared with the GuC firmware.
352  *
353  * This descriptor tells the GuC where (in GGTT space) to find the important
354  * data structures relating to this client (doorbell, process descriptor,
355  * write queue, etc).
356  */
357 
358 static void guc_init_ctx_desc(struct intel_guc *guc,
359 			      struct i915_guc_client *client)
360 {
361 	struct drm_i915_gem_object *client_obj = client->client_obj;
362 	struct drm_i915_private *dev_priv = guc_to_i915(guc);
363 	struct intel_engine_cs *engine;
364 	struct intel_context *ctx = client->owner;
365 	struct guc_context_desc desc;
366 	struct sg_table *sg;
367 	enum intel_engine_id id;
368 	u32 gfx_addr;
369 
370 	memset(&desc, 0, sizeof(desc));
371 
372 	desc.attribute = GUC_CTX_DESC_ATTR_ACTIVE | GUC_CTX_DESC_ATTR_KERNEL;
373 	desc.context_id = client->ctx_index;
374 	desc.priority = client->priority;
375 	desc.db_id = client->doorbell_id;
376 
377 	for_each_engine_id(engine, dev_priv, id) {
378 		struct guc_execlist_context *lrc = &desc.lrc[engine->guc_id];
379 		struct drm_i915_gem_object *obj;
380 		uint64_t ctx_desc;
381 
382 		/* TODO: We have a design issue to be solved here. Only when we
383 		 * receive the first batch, we know which engine is used by the
384 		 * user. But here GuC expects the lrc and ring to be pinned. It
385 		 * is not an issue for default context, which is the only one
386 		 * for now who owns a GuC client. But for future owner of GuC
387 		 * client, need to make sure lrc is pinned prior to enter here.
388 		 */
389 		obj = ctx->engine[id].state;
390 		if (!obj)
391 			break;	/* XXX: continue? */
392 
393 		ctx_desc = intel_lr_context_descriptor(ctx, engine);
394 		lrc->context_desc = (u32)ctx_desc;
395 
396 		/* The state page is after PPHWSP */
397 		gfx_addr = i915_gem_obj_ggtt_offset(obj);
398 		lrc->ring_lcra = gfx_addr + LRC_STATE_PN * PAGE_SIZE;
399 		lrc->context_id = (client->ctx_index << GUC_ELC_CTXID_OFFSET) |
400 				(engine->guc_id << GUC_ELC_ENGINE_OFFSET);
401 
402 		obj = ctx->engine[id].ringbuf->obj;
403 		gfx_addr = i915_gem_obj_ggtt_offset(obj);
404 
405 		lrc->ring_begin = gfx_addr;
406 		lrc->ring_end = gfx_addr + obj->base.size - 1;
407 		lrc->ring_next_free_location = gfx_addr;
408 		lrc->ring_current_tail_pointer_value = 0;
409 
410 		desc.engines_used |= (1 << engine->guc_id);
411 	}
412 
413 	WARN_ON(desc.engines_used == 0);
414 
415 	/*
416 	 * The doorbell, process descriptor, and workqueue are all parts
417 	 * of the client object, which the GuC will reference via the GGTT
418 	 */
419 	gfx_addr = i915_gem_obj_ggtt_offset(client_obj);
420 	desc.db_trigger_phy = sg_dma_address(client_obj->pages->sgl) +
421 				client->doorbell_offset;
422 	desc.db_trigger_cpu = (uintptr_t)client->client_base +
423 				client->doorbell_offset;
424 	desc.db_trigger_uk = gfx_addr + client->doorbell_offset;
425 	desc.process_desc = gfx_addr + client->proc_desc_offset;
426 	desc.wq_addr = gfx_addr + client->wq_offset;
427 	desc.wq_size = client->wq_size;
428 
429 	/*
430 	 * XXX: Take LRCs from an existing intel_context if this is not an
431 	 * IsKMDCreatedContext client
432 	 */
433 	desc.desc_private = (uintptr_t)client;
434 
435 	/* Pool context is pinned already */
436 	sg = guc->ctx_pool_obj->pages;
437 	sg_pcopy_from_buffer(sg->sgl, sg->nents, &desc, sizeof(desc),
438 			     sizeof(desc) * client->ctx_index);
439 }
440 
441 static void guc_fini_ctx_desc(struct intel_guc *guc,
442 			      struct i915_guc_client *client)
443 {
444 	struct guc_context_desc desc;
445 	struct sg_table *sg;
446 
447 	memset(&desc, 0, sizeof(desc));
448 
449 	sg = guc->ctx_pool_obj->pages;
450 	sg_pcopy_from_buffer(sg->sgl, sg->nents, &desc, sizeof(desc),
451 			     sizeof(desc) * client->ctx_index);
452 }
453 
454 int i915_guc_wq_check_space(struct i915_guc_client *gc)
455 {
456 	struct guc_process_desc *desc;
457 	u32 size = sizeof(struct guc_wq_item);
458 	int ret = -ETIMEDOUT, timeout_counter = 200;
459 
460 	if (!gc)
461 		return 0;
462 
463 	desc = (struct guc_process_desc *)((char *)gc->client_base + gc->proc_desc_offset);
464 
465 	while (timeout_counter-- > 0) {
466 		if (CIRC_SPACE(gc->wq_tail, desc->head, gc->wq_size) >= size) {
467 			ret = 0;
468 			break;
469 		}
470 
471 		if (timeout_counter)
472 			usleep_range(1000, 2000);
473 	};
474 
475 	return ret;
476 }
477 
478 static int guc_add_workqueue_item(struct i915_guc_client *gc,
479 				  struct drm_i915_gem_request *rq)
480 {
481 	struct guc_process_desc *desc;
482 	struct guc_wq_item *wqi;
483 	void *base;
484 	u32 tail, wq_len, wq_off, space;
485 
486 	desc = (struct guc_process_desc *)((char *)gc->client_base + gc->proc_desc_offset);
487 	space = CIRC_SPACE(gc->wq_tail, desc->head, gc->wq_size);
488 	if (WARN_ON(space < sizeof(struct guc_wq_item)))
489 		return -ENOSPC; /* shouldn't happen */
490 
491 	/* postincrement WQ tail for next time */
492 	wq_off = gc->wq_tail;
493 	gc->wq_tail += sizeof(struct guc_wq_item);
494 	gc->wq_tail &= gc->wq_size - 1;
495 
496 	/* For now workqueue item is 4 DWs; workqueue buffer is 2 pages. So we
497 	 * should not have the case where structure wqi is across page, neither
498 	 * wrapped to the beginning. This simplifies the implementation below.
499 	 *
500 	 * XXX: if not the case, we need save data to a temp wqi and copy it to
501 	 * workqueue buffer dw by dw.
502 	 */
503 	WARN_ON(sizeof(struct guc_wq_item) != 16);
504 	WARN_ON(wq_off & 3);
505 
506 	/* wq starts from the page after doorbell / process_desc */
507 	base = kmap_atomic(i915_gem_object_get_page(gc->client_obj,
508 			(wq_off + GUC_DB_SIZE) >> PAGE_SHIFT));
509 	wq_off &= PAGE_SIZE - 1;
510 	wqi = (struct guc_wq_item *)((char *)base + wq_off);
511 
512 	/* len does not include the header */
513 	wq_len = sizeof(struct guc_wq_item) / sizeof(u32) - 1;
514 	wqi->header = WQ_TYPE_INORDER |
515 			(wq_len << WQ_LEN_SHIFT) |
516 			(rq->engine->guc_id << WQ_TARGET_SHIFT) |
517 			WQ_NO_WCFLUSH_WAIT;
518 
519 	/* The GuC wants only the low-order word of the context descriptor */
520 	wqi->context_desc = (u32)intel_lr_context_descriptor(rq->ctx,
521 							     rq->engine);
522 
523 	/* The GuC firmware wants the tail index in QWords, not bytes */
524 	tail = rq->ringbuf->tail >> 3;
525 	wqi->ring_tail = tail << WQ_RING_TAIL_SHIFT;
526 	wqi->fence_id = 0; /*XXX: what fence to be here */
527 
528 	kunmap_atomic(base);
529 
530 	return 0;
531 }
532 
533 /**
534  * i915_guc_submit() - Submit commands through GuC
535  * @client:	the guc client where commands will go through
536  * @rq:		request associated with the commands
537  *
538  * Return:	0 if succeed
539  */
540 int i915_guc_submit(struct i915_guc_client *client,
541 		    struct drm_i915_gem_request *rq)
542 {
543 	struct intel_guc *guc = client->guc;
544 	unsigned int engine_id = rq->engine->guc_id;
545 	int q_ret, b_ret;
546 
547 	q_ret = guc_add_workqueue_item(client, rq);
548 	if (q_ret == 0)
549 		b_ret = guc_ring_doorbell(client);
550 
551 	client->submissions[engine_id] += 1;
552 	if (q_ret) {
553 		client->q_fail += 1;
554 		client->retcode = q_ret;
555 	} else if (b_ret) {
556 		client->b_fail += 1;
557 		client->retcode = q_ret = b_ret;
558 	} else {
559 		client->retcode = 0;
560 	}
561 	guc->submissions[engine_id] += 1;
562 	guc->last_seqno[engine_id] = rq->seqno;
563 
564 	return q_ret;
565 }
566 
567 /*
568  * Everything below here is concerned with setup & teardown, and is
569  * therefore not part of the somewhat time-critical batch-submission
570  * path of i915_guc_submit() above.
571  */
572 
573 /**
574  * gem_allocate_guc_obj() - Allocate gem object for GuC usage
575  * @dev:	drm device
576  * @size:	size of object
577  *
578  * This is a wrapper to create a gem obj. In order to use it inside GuC, the
579  * object needs to be pinned lifetime. Also we must pin it to gtt space other
580  * than [0, GUC_WOPCM_TOP) because this range is reserved inside GuC.
581  *
582  * Return:	A drm_i915_gem_object if successful, otherwise NULL.
583  */
584 static struct drm_i915_gem_object *gem_allocate_guc_obj(struct drm_device *dev,
585 							u32 size)
586 {
587 	struct drm_i915_private *dev_priv = dev->dev_private;
588 	struct drm_i915_gem_object *obj;
589 
590 	obj = i915_gem_alloc_object(dev, size);
591 	if (!obj)
592 		return NULL;
593 
594 	if (i915_gem_object_get_pages(obj)) {
595 		drm_gem_object_unreference(&obj->base);
596 		return NULL;
597 	}
598 
599 	if (i915_gem_obj_ggtt_pin(obj, PAGE_SIZE,
600 			PIN_OFFSET_BIAS | GUC_WOPCM_TOP)) {
601 		drm_gem_object_unreference(&obj->base);
602 		return NULL;
603 	}
604 
605 	/* Invalidate GuC TLB to let GuC take the latest updates to GTT. */
606 	I915_WRITE(GEN8_GTCR, GEN8_GTCR_INVALIDATE);
607 
608 	return obj;
609 }
610 
611 /**
612  * gem_release_guc_obj() - Release gem object allocated for GuC usage
613  * @obj:	gem obj to be released
614  */
615 static void gem_release_guc_obj(struct drm_i915_gem_object *obj)
616 {
617 	if (!obj)
618 		return;
619 
620 	if (i915_gem_obj_is_pinned(obj))
621 		i915_gem_object_ggtt_unpin(obj);
622 
623 	drm_gem_object_unreference(&obj->base);
624 }
625 
626 static void guc_client_free(struct drm_device *dev,
627 			    struct i915_guc_client *client)
628 {
629 	struct drm_i915_private *dev_priv = dev->dev_private;
630 	struct intel_guc *guc = &dev_priv->guc;
631 
632 	if (!client)
633 		return;
634 
635 	/*
636 	 * XXX: wait for any outstanding submissions before freeing memory.
637 	 * Be sure to drop any locks
638 	 */
639 
640 	if (client->client_base) {
641 		/*
642 		 * If we got as far as setting up a doorbell, make sure
643 		 * we shut it down before unmapping & deallocating the
644 		 * memory. So first disable the doorbell, then tell the
645 		 * GuC that we've finished with it, finally deallocate
646 		 * it in our bitmap
647 		 */
648 		if (client->doorbell_id != GUC_INVALID_DOORBELL_ID) {
649 			guc_disable_doorbell(guc, client);
650 			host2guc_release_doorbell(guc, client);
651 			release_doorbell(guc, client->doorbell_id);
652 		}
653 
654 		kunmap(kmap_to_page(client->client_base));
655 	}
656 
657 	gem_release_guc_obj(client->client_obj);
658 
659 	if (client->ctx_index != GUC_INVALID_CTX_ID) {
660 		guc_fini_ctx_desc(guc, client);
661 		ida_simple_remove(&guc->ctx_ids, client->ctx_index);
662 	}
663 
664 	kfree(client);
665 }
666 
667 /**
668  * guc_client_alloc() - Allocate an i915_guc_client
669  * @dev:	drm device
670  * @priority:	four levels priority _CRITICAL, _HIGH, _NORMAL and _LOW
671  * 		The kernel client to replace ExecList submission is created with
672  * 		NORMAL priority. Priority of a client for scheduler can be HIGH,
673  * 		while a preemption context can use CRITICAL.
674  * @ctx:	the context that owns the client (we use the default render
675  * 		context)
676  *
677  * Return:	An i915_guc_client object if success, else NULL.
678  */
679 static struct i915_guc_client *guc_client_alloc(struct drm_device *dev,
680 						uint32_t priority,
681 						struct intel_context *ctx)
682 {
683 	struct i915_guc_client *client;
684 	struct drm_i915_private *dev_priv = dev->dev_private;
685 	struct intel_guc *guc = &dev_priv->guc;
686 	struct drm_i915_gem_object *obj;
687 
688 	client = kzalloc(sizeof(*client), GFP_KERNEL);
689 	if (!client)
690 		return NULL;
691 
692 	client->doorbell_id = GUC_INVALID_DOORBELL_ID;
693 	client->priority = priority;
694 	client->owner = ctx;
695 	client->guc = guc;
696 
697 	client->ctx_index = (uint32_t)ida_simple_get(&guc->ctx_ids, 0,
698 			GUC_MAX_GPU_CONTEXTS, GFP_KERNEL);
699 	if (client->ctx_index >= GUC_MAX_GPU_CONTEXTS) {
700 		client->ctx_index = GUC_INVALID_CTX_ID;
701 		goto err;
702 	}
703 
704 	/* The first page is doorbell/proc_desc. Two followed pages are wq. */
705 	obj = gem_allocate_guc_obj(dev, GUC_DB_SIZE + GUC_WQ_SIZE);
706 	if (!obj)
707 		goto err;
708 
709 	/* We'll keep just the first (doorbell/proc) page permanently kmap'd. */
710 	client->client_obj = obj;
711 	client->client_base = kmap(i915_gem_object_get_page(obj, 0));
712 	client->wq_offset = GUC_DB_SIZE;
713 	client->wq_size = GUC_WQ_SIZE;
714 
715 	client->doorbell_offset = select_doorbell_cacheline(guc);
716 
717 	/*
718 	 * Since the doorbell only requires a single cacheline, we can save
719 	 * space by putting the application process descriptor in the same
720 	 * page. Use the half of the page that doesn't include the doorbell.
721 	 */
722 	if (client->doorbell_offset >= (GUC_DB_SIZE / 2))
723 		client->proc_desc_offset = 0;
724 	else
725 		client->proc_desc_offset = (GUC_DB_SIZE / 2);
726 
727 	client->doorbell_id = assign_doorbell(guc, client->priority);
728 	if (client->doorbell_id == GUC_INVALID_DOORBELL_ID)
729 		/* XXX: evict a doorbell instead */
730 		goto err;
731 
732 	guc_init_proc_desc(guc, client);
733 	guc_init_ctx_desc(guc, client);
734 	guc_init_doorbell(guc, client);
735 
736 	/* XXX: Any cache flushes needed? General domain mgmt calls? */
737 
738 	if (host2guc_allocate_doorbell(guc, client))
739 		goto err;
740 
741 	DRM_DEBUG_DRIVER("new priority %u client %p: ctx_index %u db_id %u\n",
742 		priority, client, client->ctx_index, client->doorbell_id);
743 
744 	return client;
745 
746 err:
747 	DRM_ERROR("FAILED to create priority %u GuC client!\n", priority);
748 
749 	guc_client_free(dev, client);
750 	return NULL;
751 }
752 
753 static void guc_create_log(struct intel_guc *guc)
754 {
755 	struct drm_i915_private *dev_priv = guc_to_i915(guc);
756 	struct drm_i915_gem_object *obj;
757 	unsigned long offset;
758 	uint32_t size, flags;
759 
760 	if (i915.guc_log_level < GUC_LOG_VERBOSITY_MIN)
761 		return;
762 
763 	if (i915.guc_log_level > GUC_LOG_VERBOSITY_MAX)
764 		i915.guc_log_level = GUC_LOG_VERBOSITY_MAX;
765 
766 	/* The first page is to save log buffer state. Allocate one
767 	 * extra page for others in case for overlap */
768 	size = (1 + GUC_LOG_DPC_PAGES + 1 +
769 		GUC_LOG_ISR_PAGES + 1 +
770 		GUC_LOG_CRASH_PAGES + 1) << PAGE_SHIFT;
771 
772 	obj = guc->log_obj;
773 	if (!obj) {
774 		obj = gem_allocate_guc_obj(dev_priv->dev, size);
775 		if (!obj) {
776 			/* logging will be off */
777 			i915.guc_log_level = -1;
778 			return;
779 		}
780 
781 		guc->log_obj = obj;
782 	}
783 
784 	/* each allocated unit is a page */
785 	flags = GUC_LOG_VALID | GUC_LOG_NOTIFY_ON_HALF_FULL |
786 		(GUC_LOG_DPC_PAGES << GUC_LOG_DPC_SHIFT) |
787 		(GUC_LOG_ISR_PAGES << GUC_LOG_ISR_SHIFT) |
788 		(GUC_LOG_CRASH_PAGES << GUC_LOG_CRASH_SHIFT);
789 
790 	offset = i915_gem_obj_ggtt_offset(obj) >> PAGE_SHIFT; /* in pages */
791 	guc->log_flags = (offset << GUC_LOG_BUF_ADDR_SHIFT) | flags;
792 }
793 
794 static void init_guc_policies(struct guc_policies *policies)
795 {
796 	struct guc_policy *policy;
797 	u32 p, i;
798 
799 	policies->dpc_promote_time = 500000;
800 	policies->max_num_work_items = POLICY_MAX_NUM_WI;
801 
802 	for (p = 0; p < GUC_CTX_PRIORITY_NUM; p++) {
803 		for (i = GUC_RENDER_ENGINE; i < GUC_MAX_ENGINES_NUM; i++) {
804 			policy = &policies->policy[p][i];
805 
806 			policy->execution_quantum = 1000000;
807 			policy->preemption_time = 500000;
808 			policy->fault_time = 250000;
809 			policy->policy_flags = 0;
810 		}
811 	}
812 
813 	policies->is_valid = 1;
814 }
815 
816 static void guc_create_ads(struct intel_guc *guc)
817 {
818 	struct drm_i915_private *dev_priv = guc_to_i915(guc);
819 	struct drm_i915_gem_object *obj;
820 	struct guc_ads *ads;
821 	struct guc_policies *policies;
822 	struct guc_mmio_reg_state *reg_state;
823 	struct intel_engine_cs *engine;
824 	struct vm_page *page;
825 	u32 size;
826 
827 	/* The ads obj includes the struct itself and buffers passed to GuC */
828 	size = sizeof(struct guc_ads) + sizeof(struct guc_policies) +
829 			sizeof(struct guc_mmio_reg_state) +
830 			GUC_S3_SAVE_SPACE_PAGES * PAGE_SIZE;
831 
832 	obj = guc->ads_obj;
833 	if (!obj) {
834 		obj = gem_allocate_guc_obj(dev_priv->dev, PAGE_ALIGN(size));
835 		if (!obj)
836 			return;
837 
838 		guc->ads_obj = obj;
839 	}
840 
841 	page = i915_gem_object_get_page(obj, 0);
842 	ads = kmap(page);
843 
844 	/*
845 	 * The GuC requires a "Golden Context" when it reinitialises
846 	 * engines after a reset. Here we use the Render ring default
847 	 * context, which must already exist and be pinned in the GGTT,
848 	 * so its address won't change after we've told the GuC where
849 	 * to find it.
850 	 */
851 	engine = &dev_priv->engine[RCS];
852 	ads->golden_context_lrca = engine->status_page.gfx_addr;
853 
854 	for_each_engine(engine, dev_priv)
855 		ads->eng_state_size[engine->guc_id] = intel_lr_context_size(engine);
856 
857 	/* GuC scheduling policies */
858 	policies = (struct guc_policies *)((char *)ads + sizeof(struct guc_ads));
859 	init_guc_policies(policies);
860 
861 	ads->scheduler_policies = i915_gem_obj_ggtt_offset(obj) +
862 			sizeof(struct guc_ads);
863 
864 	/* MMIO reg state */
865 	reg_state = (struct guc_mmio_reg_state *)((char *)policies + sizeof(struct guc_policies));
866 
867 	for_each_engine(engine, dev_priv) {
868 		reg_state->mmio_white_list[engine->guc_id].mmio_start =
869 			engine->mmio_base + GUC_MMIO_WHITE_LIST_START;
870 
871 		/* Nothing to be saved or restored for now. */
872 		reg_state->mmio_white_list[engine->guc_id].count = 0;
873 	}
874 
875 	ads->reg_state_addr = ads->scheduler_policies +
876 			sizeof(struct guc_policies);
877 
878 	ads->reg_state_buffer = ads->reg_state_addr +
879 			sizeof(struct guc_mmio_reg_state);
880 
881 	kunmap(page);
882 }
883 
884 /*
885  * Set up the memory resources to be shared with the GuC.  At this point,
886  * we require just one object that can be mapped through the GGTT.
887  */
888 int i915_guc_submission_init(struct drm_device *dev)
889 {
890 	struct drm_i915_private *dev_priv = dev->dev_private;
891 	const size_t ctxsize = sizeof(struct guc_context_desc);
892 	const size_t poolsize = GUC_MAX_GPU_CONTEXTS * ctxsize;
893 	const size_t gemsize = round_up(poolsize, PAGE_SIZE);
894 	struct intel_guc *guc = &dev_priv->guc;
895 
896 	if (!i915.enable_guc_submission)
897 		return 0; /* not enabled  */
898 
899 	if (guc->ctx_pool_obj)
900 		return 0; /* already allocated */
901 
902 	guc->ctx_pool_obj = gem_allocate_guc_obj(dev_priv->dev, gemsize);
903 	if (!guc->ctx_pool_obj)
904 		return -ENOMEM;
905 
906 	ida_init(&guc->ctx_ids);
907 
908 	guc_create_log(guc);
909 
910 	guc_create_ads(guc);
911 
912 	return 0;
913 }
914 
915 int i915_guc_submission_enable(struct drm_device *dev)
916 {
917 	struct drm_i915_private *dev_priv = dev->dev_private;
918 	struct intel_guc *guc = &dev_priv->guc;
919 	struct intel_context *ctx = dev_priv->kernel_context;
920 	struct i915_guc_client *client;
921 
922 	/* client for execbuf submission */
923 	client = guc_client_alloc(dev, GUC_CTX_PRIORITY_KMD_NORMAL, ctx);
924 	if (!client) {
925 		DRM_ERROR("Failed to create execbuf guc_client\n");
926 		return -ENOMEM;
927 	}
928 
929 	guc->execbuf_client = client;
930 
931 	host2guc_sample_forcewake(guc, client);
932 
933 	return 0;
934 }
935 
936 void i915_guc_submission_disable(struct drm_device *dev)
937 {
938 	struct drm_i915_private *dev_priv = dev->dev_private;
939 	struct intel_guc *guc = &dev_priv->guc;
940 
941 	guc_client_free(dev, guc->execbuf_client);
942 	guc->execbuf_client = NULL;
943 }
944 
945 void i915_guc_submission_fini(struct drm_device *dev)
946 {
947 	struct drm_i915_private *dev_priv = dev->dev_private;
948 	struct intel_guc *guc = &dev_priv->guc;
949 
950 	gem_release_guc_obj(dev_priv->guc.ads_obj);
951 	guc->ads_obj = NULL;
952 
953 	gem_release_guc_obj(dev_priv->guc.log_obj);
954 	guc->log_obj = NULL;
955 
956 	if (guc->ctx_pool_obj)
957 		ida_destroy(&guc->ctx_ids);
958 	gem_release_guc_obj(guc->ctx_pool_obj);
959 	guc->ctx_pool_obj = NULL;
960 }
961 
962 /**
963  * intel_guc_suspend() - notify GuC entering suspend state
964  * @dev:	drm device
965  */
966 int intel_guc_suspend(struct drm_device *dev)
967 {
968 	struct drm_i915_private *dev_priv = dev->dev_private;
969 	struct intel_guc *guc = &dev_priv->guc;
970 	struct intel_context *ctx;
971 	u32 data[3];
972 
973 	if (!i915.enable_guc_submission)
974 		return 0;
975 
976 	ctx = dev_priv->kernel_context;
977 
978 	data[0] = HOST2GUC_ACTION_ENTER_S_STATE;
979 	/* any value greater than GUC_POWER_D0 */
980 	data[1] = GUC_POWER_D1;
981 	/* first page is shared data with GuC */
982 	data[2] = i915_gem_obj_ggtt_offset(ctx->engine[RCS].state);
983 
984 	return host2guc_action(guc, data, ARRAY_SIZE(data));
985 }
986 
987 
988 /**
989  * intel_guc_resume() - notify GuC resuming from suspend state
990  * @dev:	drm device
991  */
992 int intel_guc_resume(struct drm_device *dev)
993 {
994 	struct drm_i915_private *dev_priv = dev->dev_private;
995 	struct intel_guc *guc = &dev_priv->guc;
996 	struct intel_context *ctx;
997 	u32 data[3];
998 
999 	if (!i915.enable_guc_submission)
1000 		return 0;
1001 
1002 	ctx = dev_priv->kernel_context;
1003 
1004 	data[0] = HOST2GUC_ACTION_EXIT_S_STATE;
1005 	data[1] = GUC_POWER_D0;
1006 	/* first page is shared data with GuC */
1007 	data[2] = i915_gem_obj_ggtt_offset(ctx->engine[RCS].state);
1008 
1009 	return host2guc_action(guc, data, ARRAY_SIZE(data));
1010 }
1011