xref: /linux/drivers/gpu/drm/i915/display/intel_display_driver.c (revision e77a8005748547fb1f10645097f13ccdd804d7e5)
1 // SPDX-License-Identifier: MIT
2 /*
3  * Copyright © 2022-2023 Intel Corporation
4  *
5  * High level display driver entry points. This is a layer between top level
6  * driver code and low level display functionality; no low level display code or
7  * details here.
8  */
9 
10 #include <linux/vga_switcheroo.h>
11 #include <acpi/video.h>
12 #include <drm/display/drm_dp_mst_helper.h>
13 #include <drm/drm_atomic_helper.h>
14 #include <drm/drm_client_event.h>
15 #include <drm/drm_mode_config.h>
16 #include <drm/drm_privacy_screen_consumer.h>
17 #include <drm/drm_probe_helper.h>
18 #include <drm/drm_vblank.h>
19 
20 #include "i915_drv.h"
21 #include "i9xx_wm.h"
22 #include "intel_acpi.h"
23 #include "intel_atomic.h"
24 #include "intel_audio.h"
25 #include "intel_bios.h"
26 #include "intel_bw.h"
27 #include "intel_cdclk.h"
28 #include "intel_color.h"
29 #include "intel_crtc.h"
30 #include "intel_display_debugfs.h"
31 #include "intel_display_driver.h"
32 #include "intel_display_irq.h"
33 #include "intel_display_power.h"
34 #include "intel_display_types.h"
35 #include "intel_display_wa.h"
36 #include "intel_dkl_phy.h"
37 #include "intel_dmc.h"
38 #include "intel_dp.h"
39 #include "intel_dp_tunnel.h"
40 #include "intel_dpll.h"
41 #include "intel_dpll_mgr.h"
42 #include "intel_fb.h"
43 #include "intel_fbc.h"
44 #include "intel_fbdev.h"
45 #include "intel_fdi.h"
46 #include "intel_gmbus.h"
47 #include "intel_hdcp.h"
48 #include "intel_hotplug.h"
49 #include "intel_hti.h"
50 #include "intel_modeset_lock.h"
51 #include "intel_modeset_setup.h"
52 #include "intel_opregion.h"
53 #include "intel_overlay.h"
54 #include "intel_plane_initial.h"
55 #include "intel_pmdemand.h"
56 #include "intel_pps.h"
57 #include "intel_quirks.h"
58 #include "intel_vga.h"
59 #include "intel_wm.h"
60 #include "skl_watermark.h"
61 
62 bool intel_display_driver_probe_defer(struct pci_dev *pdev)
63 {
64 	struct drm_privacy_screen *privacy_screen;
65 
66 	/*
67 	 * apple-gmux is needed on dual GPU MacBook Pro
68 	 * to probe the panel if we're the inactive GPU.
69 	 */
70 	if (vga_switcheroo_client_probe_defer(pdev))
71 		return true;
72 
73 	/* If the LCD panel has a privacy-screen, wait for it */
74 	privacy_screen = drm_privacy_screen_get(&pdev->dev, NULL);
75 	if (IS_ERR(privacy_screen) && PTR_ERR(privacy_screen) == -EPROBE_DEFER)
76 		return true;
77 
78 	drm_privacy_screen_put(privacy_screen);
79 
80 	return false;
81 }
82 
83 void intel_display_driver_init_hw(struct drm_i915_private *i915)
84 {
85 	struct intel_display *display = &i915->display;
86 	struct intel_cdclk_state *cdclk_state;
87 
88 	if (!HAS_DISPLAY(i915))
89 		return;
90 
91 	cdclk_state = to_intel_cdclk_state(display->cdclk.obj.state);
92 
93 	intel_update_cdclk(display);
94 	intel_cdclk_dump_config(display, &display->cdclk.hw, "Current CDCLK");
95 	cdclk_state->logical = cdclk_state->actual = display->cdclk.hw;
96 
97 	intel_display_wa_apply(i915);
98 }
99 
100 static const struct drm_mode_config_funcs intel_mode_funcs = {
101 	.fb_create = intel_user_framebuffer_create,
102 	.get_format_info = intel_fb_get_format_info,
103 	.mode_valid = intel_mode_valid,
104 	.atomic_check = intel_atomic_check,
105 	.atomic_commit = intel_atomic_commit,
106 	.atomic_state_alloc = intel_atomic_state_alloc,
107 	.atomic_state_clear = intel_atomic_state_clear,
108 	.atomic_state_free = intel_atomic_state_free,
109 };
110 
111 static const struct drm_mode_config_helper_funcs intel_mode_config_funcs = {
112 	.atomic_commit_setup = drm_dp_mst_atomic_setup_commit,
113 };
114 
115 static void intel_mode_config_init(struct drm_i915_private *i915)
116 {
117 	struct drm_mode_config *mode_config = &i915->drm.mode_config;
118 
119 	drm_mode_config_init(&i915->drm);
120 	INIT_LIST_HEAD(&i915->display.global.obj_list);
121 
122 	mode_config->min_width = 0;
123 	mode_config->min_height = 0;
124 
125 	mode_config->preferred_depth = 24;
126 	mode_config->prefer_shadow = 1;
127 
128 	mode_config->funcs = &intel_mode_funcs;
129 	mode_config->helper_private = &intel_mode_config_funcs;
130 
131 	mode_config->async_page_flip = HAS_ASYNC_FLIPS(i915);
132 
133 	/*
134 	 * Maximum framebuffer dimensions, chosen to match
135 	 * the maximum render engine surface size on gen4+.
136 	 */
137 	if (DISPLAY_VER(i915) >= 7) {
138 		mode_config->max_width = 16384;
139 		mode_config->max_height = 16384;
140 	} else if (DISPLAY_VER(i915) >= 4) {
141 		mode_config->max_width = 8192;
142 		mode_config->max_height = 8192;
143 	} else if (DISPLAY_VER(i915) == 3) {
144 		mode_config->max_width = 4096;
145 		mode_config->max_height = 4096;
146 	} else {
147 		mode_config->max_width = 2048;
148 		mode_config->max_height = 2048;
149 	}
150 
151 	if (IS_I845G(i915) || IS_I865G(i915)) {
152 		mode_config->cursor_width = IS_I845G(i915) ? 64 : 512;
153 		mode_config->cursor_height = 1023;
154 	} else if (IS_I830(i915) || IS_I85X(i915) ||
155 		   IS_I915G(i915) || IS_I915GM(i915)) {
156 		mode_config->cursor_width = 64;
157 		mode_config->cursor_height = 64;
158 	} else {
159 		mode_config->cursor_width = 256;
160 		mode_config->cursor_height = 256;
161 	}
162 }
163 
164 static void intel_mode_config_cleanup(struct drm_i915_private *i915)
165 {
166 	intel_atomic_global_obj_cleanup(i915);
167 	drm_mode_config_cleanup(&i915->drm);
168 }
169 
170 static void intel_plane_possible_crtcs_init(struct drm_i915_private *dev_priv)
171 {
172 	struct intel_display *display = &dev_priv->display;
173 	struct intel_plane *plane;
174 
175 	for_each_intel_plane(&dev_priv->drm, plane) {
176 		struct intel_crtc *crtc = intel_crtc_for_pipe(display,
177 							      plane->pipe);
178 
179 		plane->base.possible_crtcs = drm_crtc_mask(&crtc->base);
180 	}
181 }
182 
183 void intel_display_driver_early_probe(struct drm_i915_private *i915)
184 {
185 	if (!HAS_DISPLAY(i915))
186 		return;
187 
188 	spin_lock_init(&i915->display.fb_tracking.lock);
189 	mutex_init(&i915->display.backlight.lock);
190 	mutex_init(&i915->display.audio.mutex);
191 	mutex_init(&i915->display.wm.wm_mutex);
192 	mutex_init(&i915->display.pps.mutex);
193 	mutex_init(&i915->display.hdcp.hdcp_mutex);
194 
195 	intel_display_irq_init(i915);
196 	intel_dkl_phy_init(i915);
197 	intel_color_init_hooks(&i915->display);
198 	intel_init_cdclk_hooks(&i915->display);
199 	intel_audio_hooks_init(i915);
200 	intel_dpll_init_clock_hook(i915);
201 	intel_init_display_hooks(i915);
202 	intel_fdi_init_hook(i915);
203 	intel_dmc_wl_init(&i915->display);
204 }
205 
206 /* part #1: call before irq install */
207 int intel_display_driver_probe_noirq(struct drm_i915_private *i915)
208 {
209 	struct intel_display *display = &i915->display;
210 	int ret;
211 
212 	if (i915_inject_probe_failure(i915))
213 		return -ENODEV;
214 
215 	if (HAS_DISPLAY(i915)) {
216 		ret = drm_vblank_init(&i915->drm,
217 				      INTEL_NUM_PIPES(i915));
218 		if (ret)
219 			return ret;
220 	}
221 
222 	intel_bios_init(display);
223 
224 	ret = intel_vga_register(display);
225 	if (ret)
226 		goto cleanup_bios;
227 
228 	/* FIXME: completely on the wrong abstraction layer */
229 	ret = intel_power_domains_init(i915);
230 	if (ret < 0)
231 		goto cleanup_vga;
232 
233 	intel_pmdemand_init_early(i915);
234 
235 	intel_power_domains_init_hw(i915, false);
236 
237 	if (!HAS_DISPLAY(i915))
238 		return 0;
239 
240 	intel_dmc_init(display);
241 
242 	i915->display.wq.modeset = alloc_ordered_workqueue("i915_modeset", 0);
243 	i915->display.wq.flip = alloc_workqueue("i915_flip", WQ_HIGHPRI |
244 						WQ_UNBOUND, WQ_UNBOUND_MAX_ACTIVE);
245 
246 	intel_mode_config_init(i915);
247 
248 	ret = intel_cdclk_init(display);
249 	if (ret)
250 		goto cleanup_vga_client_pw_domain_dmc;
251 
252 	ret = intel_color_init(display);
253 	if (ret)
254 		goto cleanup_vga_client_pw_domain_dmc;
255 
256 	ret = intel_dbuf_init(i915);
257 	if (ret)
258 		goto cleanup_vga_client_pw_domain_dmc;
259 
260 	ret = intel_bw_init(i915);
261 	if (ret)
262 		goto cleanup_vga_client_pw_domain_dmc;
263 
264 	ret = intel_pmdemand_init(i915);
265 	if (ret)
266 		goto cleanup_vga_client_pw_domain_dmc;
267 
268 	intel_init_quirks(display);
269 
270 	intel_fbc_init(display);
271 
272 	return 0;
273 
274 cleanup_vga_client_pw_domain_dmc:
275 	intel_dmc_fini(display);
276 	intel_power_domains_driver_remove(i915);
277 cleanup_vga:
278 	intel_vga_unregister(display);
279 cleanup_bios:
280 	intel_bios_driver_remove(display);
281 
282 	return ret;
283 }
284 
285 static void set_display_access(struct drm_i915_private *i915,
286 			       bool any_task_allowed,
287 			       struct task_struct *allowed_task)
288 {
289 	struct drm_modeset_acquire_ctx ctx;
290 	int err;
291 
292 	intel_modeset_lock_ctx_retry(&ctx, NULL, 0, err) {
293 		err = drm_modeset_lock_all_ctx(&i915->drm, &ctx);
294 		if (err)
295 			continue;
296 
297 		i915->display.access.any_task_allowed = any_task_allowed;
298 		i915->display.access.allowed_task = allowed_task;
299 	}
300 
301 	drm_WARN_ON(&i915->drm, err);
302 }
303 
304 /**
305  * intel_display_driver_enable_user_access - Enable display HW access for all threads
306  * @i915: i915 device instance
307  *
308  * Enable the display HW access for all threads. Examples for such accesses
309  * are modeset commits and connector probing.
310  *
311  * This function should be called during driver loading and system resume once
312  * all the HW initialization steps are done.
313  */
314 void intel_display_driver_enable_user_access(struct drm_i915_private *i915)
315 {
316 	set_display_access(i915, true, NULL);
317 
318 	intel_hpd_enable_detection_work(i915);
319 }
320 
321 /**
322  * intel_display_driver_disable_user_access - Disable display HW access for user threads
323  * @i915: i915 device instance
324  *
325  * Disable the display HW access for user threads. Examples for such accesses
326  * are modeset commits and connector probing. For the current thread the
327  * access is still enabled, which should only perform HW init/deinit
328  * programming (as the initial modeset during driver loading or the disabling
329  * modeset during driver unloading and system suspend/shutdown). This function
330  * should be followed by calling either intel_display_driver_enable_user_access()
331  * after completing the HW init programming or
332  * intel_display_driver_suspend_access() after completing the HW deinit
333  * programming.
334  *
335  * This function should be called during driver loading/unloading and system
336  * suspend/shutdown before starting the HW init/deinit programming.
337  */
338 void intel_display_driver_disable_user_access(struct drm_i915_private *i915)
339 {
340 	intel_hpd_disable_detection_work(i915);
341 
342 	set_display_access(i915, false, current);
343 }
344 
345 /**
346  * intel_display_driver_suspend_access - Suspend display HW access for all threads
347  * @i915: i915 device instance
348  *
349  * Disable the display HW access for all threads. Examples for such accesses
350  * are modeset commits and connector probing. This call should be either
351  * followed by calling intel_display_driver_resume_access(), or the driver
352  * should be unloaded/shutdown.
353  *
354  * This function should be called during driver unloading and system
355  * suspend/shutdown after completing the HW deinit programming.
356  */
357 void intel_display_driver_suspend_access(struct drm_i915_private *i915)
358 {
359 	set_display_access(i915, false, NULL);
360 }
361 
362 /**
363  * intel_display_driver_resume_access - Resume display HW access for the resume thread
364  * @i915: i915 device instance
365  *
366  * Enable the display HW access for the current resume thread, keeping the
367  * access disabled for all other (user) threads. Examples for such accesses
368  * are modeset commits and connector probing. The resume thread should only
369  * perform HW init programming (as the restoring modeset). This function
370  * should be followed by calling intel_display_driver_enable_user_access(),
371  * after completing the HW init programming steps.
372  *
373  * This function should be called during system resume before starting the HW
374  * init steps.
375  */
376 void intel_display_driver_resume_access(struct drm_i915_private *i915)
377 {
378 	set_display_access(i915, false, current);
379 }
380 
381 /**
382  * intel_display_driver_check_access - Check if the current thread has disaplay HW access
383  * @i915: i915 device instance
384  *
385  * Check whether the current thread has display HW access, print a debug
386  * message if it doesn't. Such accesses are modeset commits and connector
387  * probing. If the function returns %false any HW access should be prevented.
388  *
389  * Returns %true if the current thread has display HW access, %false
390  * otherwise.
391  */
392 bool intel_display_driver_check_access(struct drm_i915_private *i915)
393 {
394 	char comm[TASK_COMM_LEN];
395 	char current_task[TASK_COMM_LEN + 16];
396 	char allowed_task[TASK_COMM_LEN + 16] = "none";
397 
398 	if (i915->display.access.any_task_allowed ||
399 	    i915->display.access.allowed_task == current)
400 		return true;
401 
402 	snprintf(current_task, sizeof(current_task), "%s[%d]",
403 		 get_task_comm(comm, current),
404 		 task_pid_vnr(current));
405 
406 	if (i915->display.access.allowed_task)
407 		snprintf(allowed_task, sizeof(allowed_task), "%s[%d]",
408 			 get_task_comm(comm, i915->display.access.allowed_task),
409 			 task_pid_vnr(i915->display.access.allowed_task));
410 
411 	drm_dbg_kms(&i915->drm,
412 		    "Reject display access from task %s (allowed to %s)\n",
413 		    current_task, allowed_task);
414 
415 	return false;
416 }
417 
418 /* part #2: call after irq install, but before gem init */
419 int intel_display_driver_probe_nogem(struct drm_i915_private *i915)
420 {
421 	struct intel_display *display = &i915->display;
422 	struct drm_device *dev = display->drm;
423 	enum pipe pipe;
424 	int ret;
425 
426 	if (!HAS_DISPLAY(i915))
427 		return 0;
428 
429 	intel_wm_init(i915);
430 
431 	intel_panel_sanitize_ssc(i915);
432 
433 	intel_pps_setup(display);
434 
435 	intel_gmbus_setup(display);
436 
437 	drm_dbg_kms(&i915->drm, "%d display pipe%s available.\n",
438 		    INTEL_NUM_PIPES(i915),
439 		    INTEL_NUM_PIPES(i915) > 1 ? "s" : "");
440 
441 	for_each_pipe(i915, pipe) {
442 		ret = intel_crtc_init(i915, pipe);
443 		if (ret)
444 			goto err_mode_config;
445 	}
446 
447 	intel_plane_possible_crtcs_init(i915);
448 	intel_shared_dpll_init(i915);
449 	intel_fdi_pll_freq_update(i915);
450 
451 	intel_update_czclk(i915);
452 	intel_display_driver_init_hw(i915);
453 	intel_dpll_update_ref_clks(i915);
454 
455 	if (display->cdclk.max_cdclk_freq == 0)
456 		intel_update_max_cdclk(display);
457 
458 	intel_hti_init(display);
459 
460 	/* Just disable it once at startup */
461 	intel_vga_disable(display);
462 	intel_setup_outputs(i915);
463 
464 	ret = intel_dp_tunnel_mgr_init(display);
465 	if (ret)
466 		goto err_hdcp;
467 
468 	intel_display_driver_disable_user_access(i915);
469 
470 	drm_modeset_lock_all(dev);
471 	intel_modeset_setup_hw_state(i915, dev->mode_config.acquire_ctx);
472 	intel_acpi_assign_connector_fwnodes(display);
473 	drm_modeset_unlock_all(dev);
474 
475 	intel_initial_plane_config(i915);
476 
477 	/*
478 	 * Make sure hardware watermarks really match the state we read out.
479 	 * Note that we need to do this after reconstructing the BIOS fb's
480 	 * since the watermark calculation done here will use pstate->fb.
481 	 */
482 	if (!HAS_GMCH(i915))
483 		ilk_wm_sanitize(i915);
484 
485 	return 0;
486 
487 err_hdcp:
488 	intel_hdcp_component_fini(display);
489 err_mode_config:
490 	intel_mode_config_cleanup(i915);
491 
492 	return ret;
493 }
494 
495 /* part #3: call after gem init */
496 int intel_display_driver_probe(struct drm_i915_private *i915)
497 {
498 	struct intel_display *display = &i915->display;
499 	int ret;
500 
501 	if (!HAS_DISPLAY(i915))
502 		return 0;
503 
504 	/*
505 	 * This will bind stuff into ggtt, so it needs to be done after
506 	 * the BIOS fb takeover and whatever else magic ggtt reservations
507 	 * happen during gem/ggtt init.
508 	 */
509 	intel_hdcp_component_init(display);
510 
511 	/*
512 	 * Force all active planes to recompute their states. So that on
513 	 * mode_setcrtc after probe, all the intel_plane_state variables
514 	 * are already calculated and there is no assert_plane warnings
515 	 * during bootup.
516 	 */
517 	ret = intel_initial_commit(&i915->drm);
518 	if (ret)
519 		drm_dbg_kms(&i915->drm, "Initial modeset failed, %d\n", ret);
520 
521 	intel_overlay_setup(i915);
522 
523 	/* Only enable hotplug handling once the fbdev is fully set up. */
524 	intel_hpd_init(i915);
525 
526 	skl_watermark_ipc_init(i915);
527 
528 	return 0;
529 }
530 
531 void intel_display_driver_register(struct drm_i915_private *i915)
532 {
533 	struct intel_display *display = &i915->display;
534 	struct drm_printer p = drm_dbg_printer(&i915->drm, DRM_UT_KMS,
535 					       "i915 display info:");
536 
537 	if (!HAS_DISPLAY(i915))
538 		return;
539 
540 	/* Must be done after probing outputs */
541 	intel_opregion_register(display);
542 	intel_acpi_video_register(display);
543 
544 	intel_audio_init(i915);
545 
546 	intel_display_driver_enable_user_access(i915);
547 
548 	intel_audio_register(i915);
549 
550 	intel_display_debugfs_register(i915);
551 
552 	/*
553 	 * We need to coordinate the hotplugs with the asynchronous
554 	 * fbdev configuration, for which we use the
555 	 * fbdev->async_cookie.
556 	 */
557 	drm_kms_helper_poll_init(&i915->drm);
558 	intel_hpd_poll_disable(i915);
559 
560 	intel_fbdev_setup(i915);
561 
562 	intel_display_device_info_print(DISPLAY_INFO(i915),
563 					DISPLAY_RUNTIME_INFO(i915), &p);
564 }
565 
566 /* part #1: call before irq uninstall */
567 void intel_display_driver_remove(struct drm_i915_private *i915)
568 {
569 	if (!HAS_DISPLAY(i915))
570 		return;
571 
572 	flush_workqueue(i915->display.wq.flip);
573 	flush_workqueue(i915->display.wq.modeset);
574 
575 	/*
576 	 * MST topology needs to be suspended so we don't have any calls to
577 	 * fbdev after it's finalized. MST will be destroyed later as part of
578 	 * drm_mode_config_cleanup()
579 	 */
580 	intel_dp_mst_suspend(i915);
581 }
582 
583 /* part #2: call after irq uninstall */
584 void intel_display_driver_remove_noirq(struct drm_i915_private *i915)
585 {
586 	struct intel_display *display = &i915->display;
587 
588 	if (!HAS_DISPLAY(i915))
589 		return;
590 
591 	intel_display_driver_suspend_access(i915);
592 
593 	/*
594 	 * Due to the hpd irq storm handling the hotplug work can re-arm the
595 	 * poll handlers. Hence disable polling after hpd handling is shut down.
596 	 */
597 	intel_hpd_poll_fini(i915);
598 
599 	intel_unregister_dsm_handler();
600 
601 	/* flush any delayed tasks or pending work */
602 	flush_workqueue(i915->unordered_wq);
603 
604 	intel_hdcp_component_fini(display);
605 
606 	intel_mode_config_cleanup(i915);
607 
608 	intel_dp_tunnel_mgr_cleanup(display);
609 
610 	intel_overlay_cleanup(i915);
611 
612 	intel_gmbus_teardown(display);
613 
614 	destroy_workqueue(i915->display.wq.flip);
615 	destroy_workqueue(i915->display.wq.modeset);
616 
617 	intel_fbc_cleanup(&i915->display);
618 }
619 
620 /* part #3: call after gem init */
621 void intel_display_driver_remove_nogem(struct drm_i915_private *i915)
622 {
623 	struct intel_display *display = &i915->display;
624 
625 	intel_dmc_fini(display);
626 
627 	intel_power_domains_driver_remove(i915);
628 
629 	intel_vga_unregister(display);
630 
631 	intel_bios_driver_remove(display);
632 }
633 
634 void intel_display_driver_unregister(struct drm_i915_private *i915)
635 {
636 	struct intel_display *display = &i915->display;
637 
638 	if (!HAS_DISPLAY(i915))
639 		return;
640 
641 	drm_client_dev_unregister(&i915->drm);
642 
643 	/*
644 	 * After flushing the fbdev (incl. a late async config which
645 	 * will have delayed queuing of a hotplug event), then flush
646 	 * the hotplug events.
647 	 */
648 	drm_kms_helper_poll_fini(&i915->drm);
649 
650 	intel_display_driver_disable_user_access(i915);
651 
652 	intel_audio_deinit(i915);
653 
654 	drm_atomic_helper_shutdown(&i915->drm);
655 
656 	acpi_video_unregister();
657 	intel_opregion_unregister(display);
658 }
659 
660 /*
661  * turn all crtc's off, but do not adjust state
662  * This has to be paired with a call to intel_modeset_setup_hw_state.
663  */
664 int intel_display_driver_suspend(struct drm_i915_private *i915)
665 {
666 	struct drm_atomic_state *state;
667 	int ret;
668 
669 	if (!HAS_DISPLAY(i915))
670 		return 0;
671 
672 	state = drm_atomic_helper_suspend(&i915->drm);
673 	ret = PTR_ERR_OR_ZERO(state);
674 	if (ret)
675 		drm_err(&i915->drm, "Suspending crtc's failed with %i\n",
676 			ret);
677 	else
678 		i915->display.restore.modeset_state = state;
679 	return ret;
680 }
681 
682 int
683 __intel_display_driver_resume(struct drm_i915_private *i915,
684 			      struct drm_atomic_state *state,
685 			      struct drm_modeset_acquire_ctx *ctx)
686 {
687 	struct intel_display *display = &i915->display;
688 	struct drm_crtc_state *crtc_state;
689 	struct drm_crtc *crtc;
690 	int ret, i;
691 
692 	intel_modeset_setup_hw_state(i915, ctx);
693 	intel_vga_redisable(display);
694 
695 	if (!state)
696 		return 0;
697 
698 	/*
699 	 * We've duplicated the state, pointers to the old state are invalid.
700 	 *
701 	 * Don't attempt to use the old state until we commit the duplicated state.
702 	 */
703 	for_each_new_crtc_in_state(state, crtc, crtc_state, i) {
704 		/*
705 		 * Force recalculation even if we restore
706 		 * current state. With fast modeset this may not result
707 		 * in a modeset when the state is compatible.
708 		 */
709 		crtc_state->mode_changed = true;
710 	}
711 
712 	/* ignore any reset values/BIOS leftovers in the WM registers */
713 	if (!HAS_GMCH(i915))
714 		to_intel_atomic_state(state)->skip_intermediate_wm = true;
715 
716 	ret = drm_atomic_helper_commit_duplicated_state(state, ctx);
717 
718 	drm_WARN_ON(&i915->drm, ret == -EDEADLK);
719 
720 	return ret;
721 }
722 
723 void intel_display_driver_resume(struct drm_i915_private *i915)
724 {
725 	struct drm_atomic_state *state = i915->display.restore.modeset_state;
726 	struct drm_modeset_acquire_ctx ctx;
727 	int ret;
728 
729 	if (!HAS_DISPLAY(i915))
730 		return;
731 
732 	i915->display.restore.modeset_state = NULL;
733 	if (state)
734 		state->acquire_ctx = &ctx;
735 
736 	drm_modeset_acquire_init(&ctx, 0);
737 
738 	while (1) {
739 		ret = drm_modeset_lock_all_ctx(&i915->drm, &ctx);
740 		if (ret != -EDEADLK)
741 			break;
742 
743 		drm_modeset_backoff(&ctx);
744 	}
745 
746 	if (!ret)
747 		ret = __intel_display_driver_resume(i915, state, &ctx);
748 
749 	skl_watermark_ipc_update(i915);
750 	drm_modeset_drop_locks(&ctx);
751 	drm_modeset_acquire_fini(&ctx);
752 
753 	if (ret)
754 		drm_err(&i915->drm,
755 			"Restoring old state failed with %i\n", ret);
756 	if (state)
757 		drm_atomic_state_put(state);
758 }
759