intel_guc.c 16.9 KB
Newer Older
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25
/*
 * Copyright © 2014-2017 Intel Corporation
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice (including the next
 * paragraph) shall be included in all copies or substantial portions of the
 * Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
 * IN THE SOFTWARE.
 *
 */

#include "intel_guc.h"
26
#include "intel_guc_ads.h"
27
#include "intel_guc_submission.h"
28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64
#include "i915_drv.h"

static void gen8_guc_raise_irq(struct intel_guc *guc)
{
	struct drm_i915_private *dev_priv = guc_to_i915(guc);

	I915_WRITE(GUC_SEND_INTERRUPT, GUC_SEND_TRIGGER);
}

static inline i915_reg_t guc_send_reg(struct intel_guc *guc, u32 i)
{
	GEM_BUG_ON(!guc->send_regs.base);
	GEM_BUG_ON(!guc->send_regs.count);
	GEM_BUG_ON(i >= guc->send_regs.count);

	return _MMIO(guc->send_regs.base + 4 * i);
}

void intel_guc_init_send_regs(struct intel_guc *guc)
{
	struct drm_i915_private *dev_priv = guc_to_i915(guc);
	enum forcewake_domains fw_domains = 0;
	unsigned int i;

	guc->send_regs.base = i915_mmio_reg_offset(SOFT_SCRATCH(0));
	guc->send_regs.count = SOFT_SCRATCH_COUNT - 1;

	for (i = 0; i < guc->send_regs.count; i++) {
		fw_domains |= intel_uncore_forcewake_for_reg(dev_priv,
					guc_send_reg(guc, i),
					FW_REG_READ | FW_REG_WRITE);
	}
	guc->send_regs.fw_domains = fw_domains;
}

void intel_guc_init_early(struct intel_guc *guc)
{
65
	intel_guc_fw_init_early(guc);
66
	intel_guc_ct_init_early(&guc->ct);
67
	intel_guc_log_init_early(&guc->log);
68 69

	mutex_init(&guc->send_mutex);
70
	spin_lock_init(&guc->irq_lock);
71
	guc->send = intel_guc_send_nop;
72
	guc->handler = intel_guc_to_host_event_handler_nop;
73 74 75
	guc->notify = gen8_guc_raise_irq;
}

76 77 78 79 80 81 82 83 84 85 86 87 88 89 90
int intel_guc_init_wq(struct intel_guc *guc)
{
	struct drm_i915_private *dev_priv = guc_to_i915(guc);

	/*
	 * GuC log buffer flush work item has to do register access to
	 * send the ack to GuC and this work item, if not synced before
	 * suspend, can potentially get executed after the GFX device is
	 * suspended.
	 * By marking the WQ as freezable, we don't have to bother about
	 * flushing of this work item from the suspend hooks, the pending
	 * work item if any will be either executed before the suspend
	 * or scheduled later on resume. This way the handling of work
	 * item can be kept same between system suspend & rpm suspend.
	 */
91 92 93 94
	guc->log.relay.flush_wq =
		alloc_ordered_workqueue("i915-guc_log",
					WQ_HIGHPRI | WQ_FREEZABLE);
	if (!guc->log.relay.flush_wq) {
95
		DRM_ERROR("Couldn't allocate workqueue for GuC log\n");
96
		return -ENOMEM;
97
	}
98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116

	/*
	 * Even though both sending GuC action, and adding a new workitem to
	 * GuC workqueue are serialized (each with its own locking), since
	 * we're using mutliple engines, it's possible that we're going to
	 * issue a preempt request with two (or more - each for different
	 * engine) workitems in GuC queue. In this situation, GuC may submit
	 * all of them, which will make us very confused.
	 * Our preemption contexts may even already be complete - before we
	 * even had the chance to sent the preempt action to GuC!. Rather
	 * than introducing yet another lock, we can just use ordered workqueue
	 * to make sure we're always sending a single preemption request with a
	 * single workitem.
	 */
	if (HAS_LOGICAL_RING_PREEMPTION(dev_priv) &&
	    USES_GUC_SUBMISSION(dev_priv)) {
		guc->preempt_wq = alloc_ordered_workqueue("i915-guc_preempt",
							  WQ_HIGHPRI);
		if (!guc->preempt_wq) {
117
			destroy_workqueue(guc->log.relay.flush_wq);
118 119
			DRM_ERROR("Couldn't allocate workqueue for GuC "
				  "preemption\n");
120 121 122 123 124 125 126 127 128 129 130 131 132 133 134
			return -ENOMEM;
		}
	}

	return 0;
}

void intel_guc_fini_wq(struct intel_guc *guc)
{
	struct drm_i915_private *dev_priv = guc_to_i915(guc);

	if (HAS_LOGICAL_RING_PREEMPTION(dev_priv) &&
	    USES_GUC_SUBMISSION(dev_priv))
		destroy_workqueue(guc->preempt_wq);

135
	destroy_workqueue(guc->log.relay.flush_wq);
136 137
}

138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174
static int guc_shared_data_create(struct intel_guc *guc)
{
	struct i915_vma *vma;
	void *vaddr;

	vma = intel_guc_allocate_vma(guc, PAGE_SIZE);
	if (IS_ERR(vma))
		return PTR_ERR(vma);

	vaddr = i915_gem_object_pin_map(vma->obj, I915_MAP_WB);
	if (IS_ERR(vaddr)) {
		i915_vma_unpin_and_release(&vma);
		return PTR_ERR(vaddr);
	}

	guc->shared_data = vma;
	guc->shared_data_vaddr = vaddr;

	return 0;
}

static void guc_shared_data_destroy(struct intel_guc *guc)
{
	i915_gem_object_unpin_map(guc->shared_data->obj);
	i915_vma_unpin_and_release(&guc->shared_data);
}

int intel_guc_init(struct intel_guc *guc)
{
	struct drm_i915_private *dev_priv = guc_to_i915(guc);
	int ret;

	ret = guc_shared_data_create(guc);
	if (ret)
		return ret;
	GEM_BUG_ON(!guc->shared_data);

175
	ret = intel_guc_log_create(&guc->log);
176 177 178 179 180 181 182 183
	if (ret)
		goto err_shared;

	ret = intel_guc_ads_create(guc);
	if (ret)
		goto err_log;
	GEM_BUG_ON(!guc->ads_vma);

184 185 186 187
	/* We need to notify the guc whenever we change the GGTT */
	i915_ggtt_enable_guc(dev_priv);

	return 0;
188 189

err_log:
190
	intel_guc_log_destroy(&guc->log);
191 192 193
err_shared:
	guc_shared_data_destroy(guc);
	return ret;
194 195 196 197 198 199 200
}

void intel_guc_fini(struct intel_guc *guc)
{
	struct drm_i915_private *dev_priv = guc_to_i915(guc);

	i915_ggtt_disable_guc(dev_priv);
201
	intel_guc_ads_destroy(guc);
202
	intel_guc_log_destroy(&guc->log);
203 204 205
	guc_shared_data_destroy(guc);
}

206
static u32 guc_ctl_debug_flags(struct intel_guc *guc)
207
{
208
	u32 level = intel_guc_log_get_level(&guc->log);
209
	u32 flags = 0;
210

211
	if (!GUC_LOG_LEVEL_IS_ENABLED(level))
212 213
		flags |= GUC_LOG_DEFAULT_DISABLED;

214
	if (!GUC_LOG_LEVEL_IS_VERBOSE(level))
215 216 217 218
		flags |= GUC_LOG_DISABLED;
	else
		flags |= GUC_LOG_LEVEL_TO_VERBOSITY(level) <<
			 GUC_LOG_VERBOSITY_SHIFT;
219

220 221 222 223 224 225 226
	if (USES_GUC_SUBMISSION(guc_to_i915(guc))) {
		u32 ads = intel_guc_ggtt_offset(guc, guc->ads_vma)
			>> PAGE_SHIFT;

		flags |= ads << GUC_ADS_ADDR_SHIFT | GUC_ADS_ENABLED;
	}

227
	return flags;
228 229
}

230 231 232 233 234 235 236 237 238 239 240
/*
 * Initialise the GuC parameter block before starting the firmware
 * transfer. These parameters are read by the firmware on startup
 * and cannot be changed thereafter.
 */
void intel_guc_init_params(struct intel_guc *guc)
{
	struct drm_i915_private *dev_priv = guc_to_i915(guc);
	u32 params[GUC_CTL_MAX_DWORDS];
	int i;

241
	memset(params, 0, sizeof(params));
242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257

	/*
	 * GuC ARAT increment is 10 ns. GuC default scheduler quantum is one
	 * second. This ARAR is calculated by:
	 * Scheduler-Quantum-in-ns / ARAT-increment-in-ns = 1000000000 / 10
	 */
	params[GUC_CTL_ARAT_HIGH] = 0;
	params[GUC_CTL_ARAT_LOW] = 100000000;

	params[GUC_CTL_WA] |= GUC_CTL_WA_UK_BY_DRIVER;

	params[GUC_CTL_FEATURE] |= GUC_CTL_DISABLE_SCHEDULER |
			GUC_CTL_VCS2_ENABLED;

	params[GUC_CTL_LOG_PARAMS] = guc->log.flags;

258
	params[GUC_CTL_DEBUG] = guc_ctl_debug_flags(guc);
259 260

	/* If GuC submission is enabled, set up additional parameters here */
261
	if (USES_GUC_SUBMISSION(dev_priv)) {
262
		u32 pgs = intel_guc_ggtt_offset(guc, guc->stage_desc_pool);
263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289
		u32 ctx_in_16 = GUC_MAX_STAGE_DESCRIPTORS / 16;

		pgs >>= PAGE_SHIFT;
		params[GUC_CTL_CTXINFO] = (pgs << GUC_CTL_BASE_ADDR_SHIFT) |
			(ctx_in_16 << GUC_CTL_CTXNUM_IN16_SHIFT);

		params[GUC_CTL_FEATURE] |= GUC_CTL_KERNEL_SUBMISSIONS;

		/* Unmask this bit to enable the GuC's internal scheduler */
		params[GUC_CTL_FEATURE] &= ~GUC_CTL_DISABLE_SCHEDULER;
	}

	/*
	 * All SOFT_SCRATCH registers are in FORCEWAKE_BLITTER domain and
	 * they are power context saved so it's ok to release forcewake
	 * when we are done here and take it again at xfer time.
	 */
	intel_uncore_forcewake_get(dev_priv, FORCEWAKE_BLITTER);

	I915_WRITE(SOFT_SCRATCH(0), 0);

	for (i = 0; i < GUC_CTL_MAX_DWORDS; i++)
		I915_WRITE(SOFT_SCRATCH(1 + i), params[i]);

	intel_uncore_forcewake_put(dev_priv, FORCEWAKE_BLITTER);
}

290 291
int intel_guc_send_nop(struct intel_guc *guc, const u32 *action, u32 len,
		       u32 *response_buf, u32 response_buf_size)
292 293 294 295 296
{
	WARN(1, "Unexpected send: action=%#x\n", *action);
	return -ENODEV;
}

297 298 299 300 301
void intel_guc_to_host_event_handler_nop(struct intel_guc *guc)
{
	WARN(1, "Unexpected event: no suitable handler\n");
}

302 303 304
/*
 * This function implements the MMIO based host to GuC interface.
 */
305 306
int intel_guc_send_mmio(struct intel_guc *guc, const u32 *action, u32 len,
			u32 *response_buf, u32 response_buf_size)
307 308 309 310 311 312 313 314 315
{
	struct drm_i915_private *dev_priv = guc_to_i915(guc);
	u32 status;
	int i;
	int ret;

	GEM_BUG_ON(!len);
	GEM_BUG_ON(len > guc->send_regs.count);

316 317 318
	/* We expect only action code */
	GEM_BUG_ON(*action & ~INTEL_GUC_MSG_CODE_MASK);

319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339
	/* If CT is available, we expect to use MMIO only during init/fini */
	GEM_BUG_ON(HAS_GUC_CT(dev_priv) &&
		*action != INTEL_GUC_ACTION_REGISTER_COMMAND_TRANSPORT_BUFFER &&
		*action != INTEL_GUC_ACTION_DEREGISTER_COMMAND_TRANSPORT_BUFFER);

	mutex_lock(&guc->send_mutex);
	intel_uncore_forcewake_get(dev_priv, guc->send_regs.fw_domains);

	for (i = 0; i < len; i++)
		I915_WRITE(guc_send_reg(guc, i), action[i]);

	POSTING_READ(guc_send_reg(guc, i - 1));

	intel_guc_notify(guc);

	/*
	 * No GuC command should ever take longer than 10ms.
	 * Fast commands should still complete in 10us.
	 */
	ret = __intel_wait_for_register_fw(dev_priv,
					   guc_send_reg(guc, 0),
340 341 342
					   INTEL_GUC_MSG_TYPE_MASK,
					   INTEL_GUC_MSG_TYPE_RESPONSE <<
					   INTEL_GUC_MSG_TYPE_SHIFT,
343
					   10, 10, &status);
344 345 346
	/* If GuC explicitly returned an error, convert it to -EIO */
	if (!ret && !INTEL_GUC_MSG_IS_RESPONSE_SUCCESS(status))
		ret = -EIO;
347

348
	if (ret) {
349 350
		DRM_ERROR("MMIO: GuC action %#x failed with error %d %#x\n",
			  action[0], ret, status);
351
		goto out;
352 353
	}

354 355 356 357 358 359 360 361 362 363 364
	if (response_buf) {
		int count = min(response_buf_size, guc->send_regs.count - 1);

		for (i = 0; i < count; i++)
			response_buf[i] = I915_READ(guc_send_reg(guc, i + 1));
	}

	/* Use data from the GuC response as our return value */
	ret = INTEL_GUC_MSG_TO_DATA(status);

out:
365 366 367 368 369 370
	intel_uncore_forcewake_put(dev_priv, guc->send_regs.fw_domains);
	mutex_unlock(&guc->send_mutex);

	return ret;
}

371
void intel_guc_to_host_event_handler_mmio(struct intel_guc *guc)
372 373
{
	struct drm_i915_private *dev_priv = guc_to_i915(guc);
374
	u32 msg, val;
375 376 377 378 379 380 381 382 383 384 385 386

	/*
	 * Sample the log buffer flush related bits & clear them out now
	 * itself from the message identity register to minimize the
	 * probability of losing a flush interrupt, when there are back
	 * to back flush interrupts.
	 * There can be a new flush interrupt, for different log buffer
	 * type (like for ISR), whilst Host is handling one (for DPC).
	 * Since same bit is used in message register for ISR & DPC, it
	 * could happen that GuC sets the bit for 2nd interrupt but Host
	 * clears out the bit on handling the 1st interrupt.
	 */
387 388 389 390 391 392
	spin_lock(&guc->irq_lock);
	val = I915_READ(SOFT_SCRATCH(15));
	msg = val & guc->msg_enabled_mask;
	I915_WRITE(SOFT_SCRATCH(15), val & ~msg);
	spin_unlock(&guc->irq_lock);

393 394 395 396 397 398 399 400
	intel_guc_to_host_process_recv_msg(guc, msg);
}

void intel_guc_to_host_process_recv_msg(struct intel_guc *guc, u32 msg)
{
	/* Make sure to handle only enabled messages */
	msg &= guc->msg_enabled_mask;

401
	if (msg & (INTEL_GUC_RECV_MSG_FLUSH_LOG_BUFFER |
402
		   INTEL_GUC_RECV_MSG_CRASH_DUMP_POSTED))
403
		intel_guc_log_handle_flush_event(&guc->log);
404 405
}

406 407 408 409 410 411
int intel_guc_sample_forcewake(struct intel_guc *guc)
{
	struct drm_i915_private *dev_priv = guc_to_i915(guc);
	u32 action[2];

	action[0] = INTEL_GUC_ACTION_SAMPLE_FORCEWAKE;
412
	/* WaRsDisableCoarsePowerGating:skl,cnl */
413
	if (!HAS_RC6(dev_priv) || NEEDS_WaRsDisableCoarsePowerGating(dev_priv))
414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444
		action[1] = 0;
	else
		/* bit 0 and 1 are for Render and Media domain separately */
		action[1] = GUC_FORCEWAKE_RENDER | GUC_FORCEWAKE_MEDIA;

	return intel_guc_send(guc, action, ARRAY_SIZE(action));
}

/**
 * intel_guc_auth_huc() - Send action to GuC to authenticate HuC ucode
 * @guc: intel_guc structure
 * @rsa_offset: rsa offset w.r.t ggtt base of huc vma
 *
 * Triggers a HuC firmware authentication request to the GuC via intel_guc_send
 * INTEL_GUC_ACTION_AUTHENTICATE_HUC interface. This function is invoked by
 * intel_huc_auth().
 *
 * Return:	non-zero code on error
 */
int intel_guc_auth_huc(struct intel_guc *guc, u32 rsa_offset)
{
	u32 action[] = {
		INTEL_GUC_ACTION_AUTHENTICATE_HUC,
		rsa_offset
	};

	return intel_guc_send(guc, action, ARRAY_SIZE(action));
}

/**
 * intel_guc_suspend() - notify GuC entering suspend state
445
 * @guc:	the guc
446
 */
447
int intel_guc_suspend(struct intel_guc *guc)
448
{
449 450 451
	u32 data[] = {
		INTEL_GUC_ACTION_ENTER_S_STATE,
		GUC_POWER_D1, /* any value greater than GUC_POWER_D0 */
452
		intel_guc_ggtt_offset(guc, guc->shared_data)
453
	};
454 455 456 457

	return intel_guc_send(guc, data, ARRAY_SIZE(data));
}

458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475
/**
 * intel_guc_reset_engine() - ask GuC to reset an engine
 * @guc:	intel_guc structure
 * @engine:	engine to be reset
 */
int intel_guc_reset_engine(struct intel_guc *guc,
			   struct intel_engine_cs *engine)
{
	u32 data[7];

	GEM_BUG_ON(!guc->execbuf_client);

	data[0] = INTEL_GUC_ACTION_REQUEST_ENGINE_RESET;
	data[1] = engine->guc_id;
	data[2] = 0;
	data[3] = 0;
	data[4] = 0;
	data[5] = guc->execbuf_client->stage_id;
476
	data[6] = intel_guc_ggtt_offset(guc, guc->shared_data);
477 478 479 480

	return intel_guc_send(guc, data, ARRAY_SIZE(data));
}

481 482
/**
 * intel_guc_resume() - notify GuC resuming from suspend state
483
 * @guc:	the guc
484
 */
485
int intel_guc_resume(struct intel_guc *guc)
486
{
487 488 489
	u32 data[] = {
		INTEL_GUC_ACTION_EXIT_S_STATE,
		GUC_POWER_D0,
490
		intel_guc_ggtt_offset(guc, guc->shared_data)
491
	};
492 493 494 495

	return intel_guc_send(guc, data, ARRAY_SIZE(data));
}

496 497 498
/**
 * DOC: GuC Address Space
 *
499
 * The layout of GuC address space is shown below:
500
 *
501
 * ::
502
 *
503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529
 *     +==============> +====================+ <== GUC_GGTT_TOP
 *     ^                |                    |
 *     |                |                    |
 *     |                |        DRAM        |
 *     |                |       Memory       |
 *     |                |                    |
 *    GuC               |                    |
 *  Address  +========> +====================+ <== WOPCM Top
 *   Space   ^          |   HW contexts RSVD |
 *     |     |          |        WOPCM       |
 *     |     |     +==> +--------------------+ <== GuC WOPCM Top
 *     |    GuC    ^    |                    |
 *     |    GGTT   |    |                    |
 *     |    Pin   GuC   |        GuC         |
 *     |    Bias WOPCM  |       WOPCM        |
 *     |     |    Size  |                    |
 *     |     |     |    |                    |
 *     v     v     v    |                    |
 *     +=====+=====+==> +====================+ <== GuC WOPCM Base
 *                      |   Non-GuC WOPCM    |
 *                      |   (HuC/Reserved)   |
 *                      +====================+ <== WOPCM Base
 *
 * The lower part of GuC Address Space [0, ggtt_pin_bias) is mapped to WOPCM
 * while upper part of GuC Address Space [ggtt_pin_bias, GUC_GGTT_TOP) is mapped
 * to DRAM. The value of the GuC ggtt_pin_bias is determined by WOPCM size and
 * actual GuC WOPCM size.
530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548
 */

/**
 * intel_guc_init_ggtt_pin_bias() - Initialize the GuC ggtt_pin_bias value.
 * @guc: intel_guc structure.
 *
 * This function will calculate and initialize the ggtt_pin_bias value based on
 * overall WOPCM size and GuC WOPCM size.
 */
void intel_guc_init_ggtt_pin_bias(struct intel_guc *guc)
{
	struct drm_i915_private *i915 = guc_to_i915(guc);

	GEM_BUG_ON(!i915->wopcm.size);
	GEM_BUG_ON(i915->wopcm.size < i915->wopcm.guc.base);

	guc->ggtt_pin_bias = i915->wopcm.size - i915->wopcm.guc.base;
}

549 550 551 552 553 554 555 556
/**
 * intel_guc_allocate_vma() - Allocate a GGTT VMA for GuC usage
 * @guc:	the guc
 * @size:	size of area to allocate (both virtual space and memory)
 *
 * This is a wrapper to create an object for use with the GuC. In order to
 * use it inside the GuC, an object needs to be pinned lifetime, so we allocate
 * both some backing storage and a range inside the Global GTT. We must pin
557
 * it in the GGTT somewhere other than than [0, GUC ggtt_pin_bias) because that
558 559 560 561 562 563 564 565 566 567 568 569 570 571 572
 * range is reserved inside GuC.
 *
 * Return:	A i915_vma if successful, otherwise an ERR_PTR.
 */
struct i915_vma *intel_guc_allocate_vma(struct intel_guc *guc, u32 size)
{
	struct drm_i915_private *dev_priv = guc_to_i915(guc);
	struct drm_i915_gem_object *obj;
	struct i915_vma *vma;
	int ret;

	obj = i915_gem_object_create(dev_priv, size);
	if (IS_ERR(obj))
		return ERR_CAST(obj);

573
	vma = i915_vma_instance(obj, &dev_priv->ggtt.vm, NULL);
574 575 576 577
	if (IS_ERR(vma))
		goto err;

	ret = i915_vma_pin(vma, 0, PAGE_SIZE,
578
			   PIN_GLOBAL | PIN_OFFSET_BIAS | guc->ggtt_pin_bias);
579 580 581 582 583 584 585 586 587 588 589
	if (ret) {
		vma = ERR_PTR(ret);
		goto err;
	}

	return vma;

err:
	i915_gem_object_put(obj);
	return vma;
}