1// SPDX-License-Identifier: MIT
2/*
3 * Copyright © 2023 Intel Corporation
4 */
5
6#include <drm/drm_atomic_helper.h>
7#include <drm/drm_print.h>
8
9#include "i915_drv.h"
10#include "intel_clock_gating.h"
11#include "intel_cx0_phy.h"
12#include "intel_display_core.h"
13#include "intel_display_driver.h"
14#include "intel_display_reset.h"
15#include "intel_display_types.h"
16#include "intel_hotplug.h"
17#include "intel_pps.h"
18
19bool intel_display_reset_test(struct intel_display *display)
20{
21 return display->params.force_reset_modeset_test;
22}
23
24/* returns true if intel_display_reset_finish() needs to be called */
25bool intel_display_reset_prepare(struct intel_display *display,
26 modeset_stuck_fn modeset_stuck, void *context)
27{
28 struct drm_modeset_acquire_ctx *ctx = &display->restore.reset_ctx;
29 struct drm_atomic_state *state;
30 int ret;
31
32 if (!HAS_DISPLAY(display))
33 return false;
34
35 if (atomic_read(v: &display->restore.pending_fb_pin)) {
36 drm_dbg_kms(display->drm,
37 "Modeset potentially stuck, unbreaking through wedging\n");
38 modeset_stuck(context);
39 }
40
41 /*
42 * Need mode_config.mutex so that we don't
43 * trample ongoing ->detect() and whatnot.
44 */
45 mutex_lock(&display->drm->mode_config.mutex);
46 drm_modeset_acquire_init(ctx, flags: 0);
47 while (1) {
48 ret = drm_modeset_lock_all_ctx(dev: display->drm, ctx);
49 if (ret != -EDEADLK)
50 break;
51
52 drm_modeset_backoff(ctx);
53 }
54 /*
55 * Disabling the crtcs gracefully seems nicer. Also the
56 * g33 docs say we should at least disable all the planes.
57 */
58 state = drm_atomic_helper_duplicate_state(dev: display->drm, ctx);
59 if (IS_ERR(ptr: state)) {
60 ret = PTR_ERR(ptr: state);
61 drm_err(display->drm, "Duplicating state failed with %i\n",
62 ret);
63 return true;
64 }
65
66 ret = drm_atomic_helper_disable_all(dev: display->drm, ctx);
67 if (ret) {
68 drm_err(display->drm, "Suspending crtc's failed with %i\n",
69 ret);
70 drm_atomic_state_put(state);
71 return true;
72 }
73
74 display->restore.modeset_state = state;
75 state->acquire_ctx = ctx;
76
77 return true;
78}
79
80void intel_display_reset_finish(struct intel_display *display, bool test_only)
81{
82 struct drm_i915_private *i915 = to_i915(dev: display->drm);
83 struct drm_modeset_acquire_ctx *ctx = &display->restore.reset_ctx;
84 struct drm_atomic_state *state;
85 int ret;
86
87 if (!HAS_DISPLAY(display))
88 return;
89
90 state = fetch_and_zero(&display->restore.modeset_state);
91 if (!state)
92 goto unlock;
93
94 /* reset doesn't touch the display */
95 if (test_only) {
96 /* for testing only restore the display */
97 ret = drm_atomic_helper_commit_duplicated_state(state, ctx);
98 if (ret) {
99 drm_WARN_ON(display->drm, ret == -EDEADLK);
100 drm_err(display->drm,
101 "Restoring old state failed with %i\n", ret);
102 }
103 } else {
104 /*
105 * The display has been reset as well,
106 * so need a full re-initialization.
107 */
108 intel_pps_unlock_regs_wa(display);
109 intel_display_driver_init_hw(display);
110 intel_clock_gating_init(i915);
111 intel_cx0_pll_power_save_wa(display);
112 intel_hpd_init(display);
113
114 ret = __intel_display_driver_resume(display, state, ctx);
115 if (ret)
116 drm_err(display->drm,
117 "Restoring old state failed with %i\n", ret);
118
119 intel_hpd_poll_disable(display);
120 }
121
122 drm_atomic_state_put(state);
123unlock:
124 drm_modeset_drop_locks(ctx);
125 drm_modeset_acquire_fini(ctx);
126 mutex_unlock(lock: &display->drm->mode_config.mutex);
127}
128

source code of linux/drivers/gpu/drm/i915/display/intel_display_reset.c