xref: /openbmc/linux/drivers/gpu/drm/i915/gt/uc/intel_uc.c (revision a531b0c2)
1 // SPDX-License-Identifier: MIT
2 /*
3  * Copyright © 2016-2019 Intel Corporation
4  */
5 
6 #include "gt/intel_gt.h"
7 #include "gt/intel_reset.h"
8 #include "intel_guc.h"
9 #include "intel_guc_ads.h"
10 #include "intel_guc_submission.h"
11 #include "intel_uc.h"
12 
13 #include "i915_drv.h"
14 
15 static const struct intel_uc_ops uc_ops_off;
16 static const struct intel_uc_ops uc_ops_on;
17 
18 static void uc_expand_default_options(struct intel_uc *uc)
19 {
20 	struct drm_i915_private *i915 = uc_to_gt(uc)->i915;
21 
22 	if (i915->params.enable_guc != -1)
23 		return;
24 
25 	/* Don't enable GuC/HuC on pre-Gen12 */
26 	if (GRAPHICS_VER(i915) < 12) {
27 		i915->params.enable_guc = 0;
28 		return;
29 	}
30 
31 	/* Don't enable GuC/HuC on older Gen12 platforms */
32 	if (IS_TIGERLAKE(i915) || IS_ROCKETLAKE(i915)) {
33 		i915->params.enable_guc = 0;
34 		return;
35 	}
36 
37 	/* Intermediate platforms are HuC authentication only */
38 	if (IS_ALDERLAKE_S(i915)) {
39 		i915->params.enable_guc = ENABLE_GUC_LOAD_HUC;
40 		return;
41 	}
42 
43 	/* Default: enable HuC authentication and GuC submission */
44 	i915->params.enable_guc = ENABLE_GUC_LOAD_HUC | ENABLE_GUC_SUBMISSION;
45 }
46 
47 /* Reset GuC providing us with fresh state for both GuC and HuC.
48  */
49 static int __intel_uc_reset_hw(struct intel_uc *uc)
50 {
51 	struct intel_gt *gt = uc_to_gt(uc);
52 	int ret;
53 	u32 guc_status;
54 
55 	ret = i915_inject_probe_error(gt->i915, -ENXIO);
56 	if (ret)
57 		return ret;
58 
59 	ret = intel_reset_guc(gt);
60 	if (ret) {
61 		DRM_ERROR("Failed to reset GuC, ret = %d\n", ret);
62 		return ret;
63 	}
64 
65 	guc_status = intel_uncore_read(gt->uncore, GUC_STATUS);
66 	WARN(!(guc_status & GS_MIA_IN_RESET),
67 	     "GuC status: 0x%x, MIA core expected to be in reset\n",
68 	     guc_status);
69 
70 	return ret;
71 }
72 
73 static void __confirm_options(struct intel_uc *uc)
74 {
75 	struct drm_i915_private *i915 = uc_to_gt(uc)->i915;
76 
77 	drm_dbg(&i915->drm,
78 		"enable_guc=%d (guc:%s submission:%s huc:%s slpc:%s)\n",
79 		i915->params.enable_guc,
80 		yesno(intel_uc_wants_guc(uc)),
81 		yesno(intel_uc_wants_guc_submission(uc)),
82 		yesno(intel_uc_wants_huc(uc)),
83 		yesno(intel_uc_wants_guc_slpc(uc)));
84 
85 	if (i915->params.enable_guc == 0) {
86 		GEM_BUG_ON(intel_uc_wants_guc(uc));
87 		GEM_BUG_ON(intel_uc_wants_guc_submission(uc));
88 		GEM_BUG_ON(intel_uc_wants_huc(uc));
89 		GEM_BUG_ON(intel_uc_wants_guc_slpc(uc));
90 		return;
91 	}
92 
93 	if (!intel_uc_supports_guc(uc))
94 		drm_info(&i915->drm,
95 			 "Incompatible option enable_guc=%d - %s\n",
96 			 i915->params.enable_guc, "GuC is not supported!");
97 
98 	if (i915->params.enable_guc & ENABLE_GUC_LOAD_HUC &&
99 	    !intel_uc_supports_huc(uc))
100 		drm_info(&i915->drm,
101 			 "Incompatible option enable_guc=%d - %s\n",
102 			 i915->params.enable_guc, "HuC is not supported!");
103 
104 	if (i915->params.enable_guc & ENABLE_GUC_SUBMISSION &&
105 	    !intel_uc_supports_guc_submission(uc))
106 		drm_info(&i915->drm,
107 			 "Incompatible option enable_guc=%d - %s\n",
108 			 i915->params.enable_guc, "GuC submission is N/A");
109 
110 	if (i915->params.enable_guc & ~ENABLE_GUC_MASK)
111 		drm_info(&i915->drm,
112 			 "Incompatible option enable_guc=%d - %s\n",
113 			 i915->params.enable_guc, "undocumented flag");
114 }
115 
116 void intel_uc_init_early(struct intel_uc *uc)
117 {
118 	uc_expand_default_options(uc);
119 
120 	intel_guc_init_early(&uc->guc);
121 	intel_huc_init_early(&uc->huc);
122 
123 	__confirm_options(uc);
124 
125 	if (intel_uc_wants_guc(uc))
126 		uc->ops = &uc_ops_on;
127 	else
128 		uc->ops = &uc_ops_off;
129 }
130 
131 void intel_uc_init_late(struct intel_uc *uc)
132 {
133 	intel_guc_init_late(&uc->guc);
134 }
135 
136 void intel_uc_driver_late_release(struct intel_uc *uc)
137 {
138 }
139 
140 /**
141  * intel_uc_init_mmio - setup uC MMIO access
142  * @uc: the intel_uc structure
143  *
144  * Setup minimal state necessary for MMIO accesses later in the
145  * initialization sequence.
146  */
147 void intel_uc_init_mmio(struct intel_uc *uc)
148 {
149 	intel_guc_init_send_regs(&uc->guc);
150 }
151 
152 static void __uc_capture_load_err_log(struct intel_uc *uc)
153 {
154 	struct intel_guc *guc = &uc->guc;
155 
156 	if (guc->log.vma && !uc->load_err_log)
157 		uc->load_err_log = i915_gem_object_get(guc->log.vma->obj);
158 }
159 
160 static void __uc_free_load_err_log(struct intel_uc *uc)
161 {
162 	struct drm_i915_gem_object *log = fetch_and_zero(&uc->load_err_log);
163 
164 	if (log)
165 		i915_gem_object_put(log);
166 }
167 
168 void intel_uc_driver_remove(struct intel_uc *uc)
169 {
170 	intel_uc_fini_hw(uc);
171 	intel_uc_fini(uc);
172 	__uc_free_load_err_log(uc);
173 }
174 
175 /*
176  * Events triggered while CT buffers are disabled are logged in the SCRATCH_15
177  * register using the same bits used in the CT message payload. Since our
178  * communication channel with guc is turned off at this point, we can save the
179  * message and handle it after we turn it back on.
180  */
181 static void guc_clear_mmio_msg(struct intel_guc *guc)
182 {
183 	intel_uncore_write(guc_to_gt(guc)->uncore, SOFT_SCRATCH(15), 0);
184 }
185 
186 static void guc_get_mmio_msg(struct intel_guc *guc)
187 {
188 	u32 val;
189 
190 	spin_lock_irq(&guc->irq_lock);
191 
192 	val = intel_uncore_read(guc_to_gt(guc)->uncore, SOFT_SCRATCH(15));
193 	guc->mmio_msg |= val & guc->msg_enabled_mask;
194 
195 	/*
196 	 * clear all events, including the ones we're not currently servicing,
197 	 * to make sure we don't try to process a stale message if we enable
198 	 * handling of more events later.
199 	 */
200 	guc_clear_mmio_msg(guc);
201 
202 	spin_unlock_irq(&guc->irq_lock);
203 }
204 
205 static void guc_handle_mmio_msg(struct intel_guc *guc)
206 {
207 	/* we need communication to be enabled to reply to GuC */
208 	GEM_BUG_ON(!intel_guc_ct_enabled(&guc->ct));
209 
210 	spin_lock_irq(&guc->irq_lock);
211 	if (guc->mmio_msg) {
212 		intel_guc_to_host_process_recv_msg(guc, &guc->mmio_msg, 1);
213 		guc->mmio_msg = 0;
214 	}
215 	spin_unlock_irq(&guc->irq_lock);
216 }
217 
218 static int guc_enable_communication(struct intel_guc *guc)
219 {
220 	struct intel_gt *gt = guc_to_gt(guc);
221 	struct drm_i915_private *i915 = gt->i915;
222 	int ret;
223 
224 	GEM_BUG_ON(intel_guc_ct_enabled(&guc->ct));
225 
226 	ret = i915_inject_probe_error(i915, -ENXIO);
227 	if (ret)
228 		return ret;
229 
230 	ret = intel_guc_ct_enable(&guc->ct);
231 	if (ret)
232 		return ret;
233 
234 	/* check for mmio messages received before/during the CT enable */
235 	guc_get_mmio_msg(guc);
236 	guc_handle_mmio_msg(guc);
237 
238 	intel_guc_enable_interrupts(guc);
239 
240 	/* check for CT messages received before we enabled interrupts */
241 	spin_lock_irq(&gt->irq_lock);
242 	intel_guc_ct_event_handler(&guc->ct);
243 	spin_unlock_irq(&gt->irq_lock);
244 
245 	drm_dbg(&i915->drm, "GuC communication enabled\n");
246 
247 	return 0;
248 }
249 
250 static void guc_disable_communication(struct intel_guc *guc)
251 {
252 	struct drm_i915_private *i915 = guc_to_gt(guc)->i915;
253 
254 	/*
255 	 * Events generated during or after CT disable are logged by guc in
256 	 * via mmio. Make sure the register is clear before disabling CT since
257 	 * all events we cared about have already been processed via CT.
258 	 */
259 	guc_clear_mmio_msg(guc);
260 
261 	intel_guc_disable_interrupts(guc);
262 
263 	intel_guc_ct_disable(&guc->ct);
264 
265 	/*
266 	 * Check for messages received during/after the CT disable. We do not
267 	 * expect any messages to have arrived via CT between the interrupt
268 	 * disable and the CT disable because GuC should've been idle until we
269 	 * triggered the CT disable protocol.
270 	 */
271 	guc_get_mmio_msg(guc);
272 
273 	drm_dbg(&i915->drm, "GuC communication disabled\n");
274 }
275 
276 static void __uc_fetch_firmwares(struct intel_uc *uc)
277 {
278 	int err;
279 
280 	GEM_BUG_ON(!intel_uc_wants_guc(uc));
281 
282 	err = intel_uc_fw_fetch(&uc->guc.fw);
283 	if (err) {
284 		/* Make sure we transition out of transient "SELECTED" state */
285 		if (intel_uc_wants_huc(uc)) {
286 			drm_dbg(&uc_to_gt(uc)->i915->drm,
287 				"Failed to fetch GuC: %d disabling HuC\n", err);
288 			intel_uc_fw_change_status(&uc->huc.fw,
289 						  INTEL_UC_FIRMWARE_ERROR);
290 		}
291 
292 		return;
293 	}
294 
295 	if (intel_uc_wants_huc(uc))
296 		intel_uc_fw_fetch(&uc->huc.fw);
297 }
298 
299 static void __uc_cleanup_firmwares(struct intel_uc *uc)
300 {
301 	intel_uc_fw_cleanup_fetch(&uc->huc.fw);
302 	intel_uc_fw_cleanup_fetch(&uc->guc.fw);
303 }
304 
305 static int __uc_init(struct intel_uc *uc)
306 {
307 	struct intel_guc *guc = &uc->guc;
308 	struct intel_huc *huc = &uc->huc;
309 	int ret;
310 
311 	GEM_BUG_ON(!intel_uc_wants_guc(uc));
312 
313 	if (!intel_uc_uses_guc(uc))
314 		return 0;
315 
316 	if (i915_inject_probe_failure(uc_to_gt(uc)->i915))
317 		return -ENOMEM;
318 
319 	ret = intel_guc_init(guc);
320 	if (ret)
321 		return ret;
322 
323 	if (intel_uc_uses_huc(uc)) {
324 		ret = intel_huc_init(huc);
325 		if (ret)
326 			goto out_guc;
327 	}
328 
329 	return 0;
330 
331 out_guc:
332 	intel_guc_fini(guc);
333 	return ret;
334 }
335 
336 static void __uc_fini(struct intel_uc *uc)
337 {
338 	intel_huc_fini(&uc->huc);
339 	intel_guc_fini(&uc->guc);
340 }
341 
342 static int __uc_sanitize(struct intel_uc *uc)
343 {
344 	struct intel_guc *guc = &uc->guc;
345 	struct intel_huc *huc = &uc->huc;
346 
347 	GEM_BUG_ON(!intel_uc_supports_guc(uc));
348 
349 	intel_huc_sanitize(huc);
350 	intel_guc_sanitize(guc);
351 
352 	return __intel_uc_reset_hw(uc);
353 }
354 
355 /* Initialize and verify the uC regs related to uC positioning in WOPCM */
356 static int uc_init_wopcm(struct intel_uc *uc)
357 {
358 	struct intel_gt *gt = uc_to_gt(uc);
359 	struct intel_uncore *uncore = gt->uncore;
360 	u32 base = intel_wopcm_guc_base(&gt->i915->wopcm);
361 	u32 size = intel_wopcm_guc_size(&gt->i915->wopcm);
362 	u32 huc_agent = intel_uc_uses_huc(uc) ? HUC_LOADING_AGENT_GUC : 0;
363 	u32 mask;
364 	int err;
365 
366 	if (unlikely(!base || !size)) {
367 		i915_probe_error(gt->i915, "Unsuccessful WOPCM partitioning\n");
368 		return -E2BIG;
369 	}
370 
371 	GEM_BUG_ON(!intel_uc_supports_guc(uc));
372 	GEM_BUG_ON(!(base & GUC_WOPCM_OFFSET_MASK));
373 	GEM_BUG_ON(base & ~GUC_WOPCM_OFFSET_MASK);
374 	GEM_BUG_ON(!(size & GUC_WOPCM_SIZE_MASK));
375 	GEM_BUG_ON(size & ~GUC_WOPCM_SIZE_MASK);
376 
377 	err = i915_inject_probe_error(gt->i915, -ENXIO);
378 	if (err)
379 		return err;
380 
381 	mask = GUC_WOPCM_SIZE_MASK | GUC_WOPCM_SIZE_LOCKED;
382 	err = intel_uncore_write_and_verify(uncore, GUC_WOPCM_SIZE, size, mask,
383 					    size | GUC_WOPCM_SIZE_LOCKED);
384 	if (err)
385 		goto err_out;
386 
387 	mask = GUC_WOPCM_OFFSET_MASK | GUC_WOPCM_OFFSET_VALID | huc_agent;
388 	err = intel_uncore_write_and_verify(uncore, DMA_GUC_WOPCM_OFFSET,
389 					    base | huc_agent, mask,
390 					    base | huc_agent |
391 					    GUC_WOPCM_OFFSET_VALID);
392 	if (err)
393 		goto err_out;
394 
395 	return 0;
396 
397 err_out:
398 	i915_probe_error(gt->i915, "Failed to init uC WOPCM registers!\n");
399 	i915_probe_error(gt->i915, "%s(%#x)=%#x\n", "DMA_GUC_WOPCM_OFFSET",
400 			 i915_mmio_reg_offset(DMA_GUC_WOPCM_OFFSET),
401 			 intel_uncore_read(uncore, DMA_GUC_WOPCM_OFFSET));
402 	i915_probe_error(gt->i915, "%s(%#x)=%#x\n", "GUC_WOPCM_SIZE",
403 			 i915_mmio_reg_offset(GUC_WOPCM_SIZE),
404 			 intel_uncore_read(uncore, GUC_WOPCM_SIZE));
405 
406 	return err;
407 }
408 
409 static bool uc_is_wopcm_locked(struct intel_uc *uc)
410 {
411 	struct intel_gt *gt = uc_to_gt(uc);
412 	struct intel_uncore *uncore = gt->uncore;
413 
414 	return (intel_uncore_read(uncore, GUC_WOPCM_SIZE) & GUC_WOPCM_SIZE_LOCKED) ||
415 	       (intel_uncore_read(uncore, DMA_GUC_WOPCM_OFFSET) & GUC_WOPCM_OFFSET_VALID);
416 }
417 
418 static int __uc_check_hw(struct intel_uc *uc)
419 {
420 	if (!intel_uc_supports_guc(uc))
421 		return 0;
422 
423 	/*
424 	 * We can silently continue without GuC only if it was never enabled
425 	 * before on this system after reboot, otherwise we risk GPU hangs.
426 	 * To check if GuC was loaded before we look at WOPCM registers.
427 	 */
428 	if (uc_is_wopcm_locked(uc))
429 		return -EIO;
430 
431 	return 0;
432 }
433 
434 static int __uc_init_hw(struct intel_uc *uc)
435 {
436 	struct drm_i915_private *i915 = uc_to_gt(uc)->i915;
437 	struct intel_guc *guc = &uc->guc;
438 	struct intel_huc *huc = &uc->huc;
439 	int ret, attempts;
440 
441 	GEM_BUG_ON(!intel_uc_supports_guc(uc));
442 	GEM_BUG_ON(!intel_uc_wants_guc(uc));
443 
444 	if (!intel_uc_fw_is_loadable(&guc->fw)) {
445 		ret = __uc_check_hw(uc) ||
446 		      intel_uc_fw_is_overridden(&guc->fw) ||
447 		      intel_uc_wants_guc_submission(uc) ?
448 		      intel_uc_fw_status_to_error(guc->fw.status) : 0;
449 		goto err_out;
450 	}
451 
452 	ret = uc_init_wopcm(uc);
453 	if (ret)
454 		goto err_out;
455 
456 	intel_guc_reset_interrupts(guc);
457 
458 	/* WaEnableuKernelHeaderValidFix:skl */
459 	/* WaEnableGuCBootHashCheckNotSet:skl,bxt,kbl */
460 	if (GRAPHICS_VER(i915) == 9)
461 		attempts = 3;
462 	else
463 		attempts = 1;
464 
465 	while (attempts--) {
466 		/*
467 		 * Always reset the GuC just before (re)loading, so
468 		 * that the state and timing are fairly predictable
469 		 */
470 		ret = __uc_sanitize(uc);
471 		if (ret)
472 			goto err_out;
473 
474 		intel_huc_fw_upload(huc);
475 		intel_guc_ads_reset(guc);
476 		intel_guc_write_params(guc);
477 		ret = intel_guc_fw_upload(guc);
478 		if (ret == 0)
479 			break;
480 
481 		DRM_DEBUG_DRIVER("GuC fw load failed: %d; will reset and "
482 				 "retry %d more time(s)\n", ret, attempts);
483 	}
484 
485 	/* Did we succeded or run out of retries? */
486 	if (ret)
487 		goto err_log_capture;
488 
489 	ret = guc_enable_communication(guc);
490 	if (ret)
491 		goto err_log_capture;
492 
493 	intel_huc_auth(huc);
494 
495 	if (intel_uc_uses_guc_submission(uc))
496 		intel_guc_submission_enable(guc);
497 
498 	if (intel_uc_uses_guc_slpc(uc)) {
499 		ret = intel_guc_slpc_enable(&guc->slpc);
500 		if (ret)
501 			goto err_submission;
502 	}
503 
504 	drm_info(&i915->drm, "%s firmware %s version %u.%u %s:%s\n",
505 		 intel_uc_fw_type_repr(INTEL_UC_FW_TYPE_GUC), guc->fw.path,
506 		 guc->fw.major_ver_found, guc->fw.minor_ver_found,
507 		 "submission",
508 		 enableddisabled(intel_uc_uses_guc_submission(uc)));
509 
510 	drm_info(&i915->drm, "GuC SLPC: %s\n",
511 		 enableddisabled(intel_uc_uses_guc_slpc(uc)));
512 
513 	if (intel_uc_uses_huc(uc)) {
514 		drm_info(&i915->drm, "%s firmware %s version %u.%u %s:%s\n",
515 			 intel_uc_fw_type_repr(INTEL_UC_FW_TYPE_HUC),
516 			 huc->fw.path,
517 			 huc->fw.major_ver_found, huc->fw.minor_ver_found,
518 			 "authenticated",
519 			 yesno(intel_huc_is_authenticated(huc)));
520 	}
521 
522 	return 0;
523 
524 	/*
525 	 * We've failed to load the firmware :(
526 	 */
527 err_submission:
528 	intel_guc_submission_disable(guc);
529 err_log_capture:
530 	__uc_capture_load_err_log(uc);
531 err_out:
532 	__uc_sanitize(uc);
533 
534 	if (!ret) {
535 		drm_notice(&i915->drm, "GuC is uninitialized\n");
536 		/* We want to run without GuC submission */
537 		return 0;
538 	}
539 
540 	i915_probe_error(i915, "GuC initialization failed %d\n", ret);
541 
542 	/* We want to keep KMS alive */
543 	return -EIO;
544 }
545 
546 static void __uc_fini_hw(struct intel_uc *uc)
547 {
548 	struct intel_guc *guc = &uc->guc;
549 
550 	if (!intel_guc_is_fw_running(guc))
551 		return;
552 
553 	if (intel_uc_uses_guc_submission(uc))
554 		intel_guc_submission_disable(guc);
555 
556 	__uc_sanitize(uc);
557 }
558 
559 /**
560  * intel_uc_reset_prepare - Prepare for reset
561  * @uc: the intel_uc structure
562  *
563  * Preparing for full gpu reset.
564  */
565 void intel_uc_reset_prepare(struct intel_uc *uc)
566 {
567 	struct intel_guc *guc = &uc->guc;
568 
569 	uc->reset_in_progress = true;
570 
571 	/* Nothing to do if GuC isn't supported */
572 	if (!intel_uc_supports_guc(uc))
573 		return;
574 
575 	/* Firmware expected to be running when this function is called */
576 	if (!intel_guc_is_ready(guc))
577 		goto sanitize;
578 
579 	if (intel_uc_uses_guc_submission(uc))
580 		intel_guc_submission_reset_prepare(guc);
581 
582 sanitize:
583 	__uc_sanitize(uc);
584 }
585 
586 void intel_uc_reset(struct intel_uc *uc, bool stalled)
587 {
588 	struct intel_guc *guc = &uc->guc;
589 
590 	/* Firmware can not be running when this function is called  */
591 	if (intel_uc_uses_guc_submission(uc))
592 		intel_guc_submission_reset(guc, stalled);
593 }
594 
595 void intel_uc_reset_finish(struct intel_uc *uc)
596 {
597 	struct intel_guc *guc = &uc->guc;
598 
599 	uc->reset_in_progress = false;
600 
601 	/* Firmware expected to be running when this function is called */
602 	if (intel_guc_is_fw_running(guc) && intel_uc_uses_guc_submission(uc))
603 		intel_guc_submission_reset_finish(guc);
604 }
605 
606 void intel_uc_cancel_requests(struct intel_uc *uc)
607 {
608 	struct intel_guc *guc = &uc->guc;
609 
610 	/* Firmware can not be running when this function is called  */
611 	if (intel_uc_uses_guc_submission(uc))
612 		intel_guc_submission_cancel_requests(guc);
613 }
614 
615 void intel_uc_runtime_suspend(struct intel_uc *uc)
616 {
617 	struct intel_guc *guc = &uc->guc;
618 
619 	if (!intel_guc_is_ready(guc))
620 		return;
621 
622 	/*
623 	 * Wait for any outstanding CTB before tearing down communication /w the
624 	 * GuC.
625 	 */
626 #define OUTSTANDING_CTB_TIMEOUT_PERIOD	(HZ / 5)
627 	intel_guc_wait_for_pending_msg(guc, &guc->outstanding_submission_g2h,
628 				       false, OUTSTANDING_CTB_TIMEOUT_PERIOD);
629 	GEM_WARN_ON(atomic_read(&guc->outstanding_submission_g2h));
630 
631 	guc_disable_communication(guc);
632 }
633 
634 void intel_uc_suspend(struct intel_uc *uc)
635 {
636 	struct intel_guc *guc = &uc->guc;
637 	intel_wakeref_t wakeref;
638 	int err;
639 
640 	if (!intel_guc_is_ready(guc))
641 		return;
642 
643 	with_intel_runtime_pm(&uc_to_gt(uc)->i915->runtime_pm, wakeref) {
644 		err = intel_guc_suspend(guc);
645 		if (err)
646 			DRM_DEBUG_DRIVER("Failed to suspend GuC, err=%d", err);
647 	}
648 }
649 
650 static int __uc_resume(struct intel_uc *uc, bool enable_communication)
651 {
652 	struct intel_guc *guc = &uc->guc;
653 	struct intel_gt *gt = guc_to_gt(guc);
654 	int err;
655 
656 	if (!intel_guc_is_fw_running(guc))
657 		return 0;
658 
659 	/* Make sure we enable communication if and only if it's disabled */
660 	GEM_BUG_ON(enable_communication == intel_guc_ct_enabled(&guc->ct));
661 
662 	if (enable_communication)
663 		guc_enable_communication(guc);
664 
665 	/* If we are only resuming GuC communication but not reloading
666 	 * GuC, we need to ensure the ARAT timer interrupt is enabled
667 	 * again. In case of GuC reload, it is enabled during SLPC enable.
668 	 */
669 	if (enable_communication && intel_uc_uses_guc_slpc(uc))
670 		intel_guc_pm_intrmsk_enable(gt);
671 
672 	err = intel_guc_resume(guc);
673 	if (err) {
674 		DRM_DEBUG_DRIVER("Failed to resume GuC, err=%d", err);
675 		return err;
676 	}
677 
678 	return 0;
679 }
680 
681 int intel_uc_resume(struct intel_uc *uc)
682 {
683 	/*
684 	 * When coming out of S3/S4 we sanitize and re-init the HW, so
685 	 * communication is already re-enabled at this point.
686 	 */
687 	return __uc_resume(uc, false);
688 }
689 
690 int intel_uc_runtime_resume(struct intel_uc *uc)
691 {
692 	/*
693 	 * During runtime resume we don't sanitize, so we need to re-init
694 	 * communication as well.
695 	 */
696 	return __uc_resume(uc, true);
697 }
698 
699 static const struct intel_uc_ops uc_ops_off = {
700 	.init_hw = __uc_check_hw,
701 };
702 
703 static const struct intel_uc_ops uc_ops_on = {
704 	.sanitize = __uc_sanitize,
705 
706 	.init_fw = __uc_fetch_firmwares,
707 	.fini_fw = __uc_cleanup_firmwares,
708 
709 	.init = __uc_init,
710 	.fini = __uc_fini,
711 
712 	.init_hw = __uc_init_hw,
713 	.fini_hw = __uc_fini_hw,
714 };
715