1 // SPDX-License-Identifier: MIT
2 /*
3 * Copyright © 2023 Intel Corporation
4 */
5
6 #include <drm/drm_atomic_helper.h>
7
8 #include "i915_drv.h"
9 #include "intel_clock_gating.h"
10 #include "intel_display_driver.h"
11 #include "intel_display_reset.h"
12 #include "intel_display_types.h"
13 #include "intel_hotplug.h"
14 #include "intel_pps.h"
15
gpu_reset_clobbers_display(struct drm_i915_private * dev_priv)16 static bool gpu_reset_clobbers_display(struct drm_i915_private *dev_priv)
17 {
18 return (INTEL_INFO(dev_priv)->gpu_reset_clobbers_display &&
19 intel_has_gpu_reset(to_gt(dev_priv)));
20 }
21
intel_display_reset_prepare(struct drm_i915_private * dev_priv)22 void intel_display_reset_prepare(struct drm_i915_private *dev_priv)
23 {
24 struct drm_modeset_acquire_ctx *ctx = &dev_priv->display.restore.reset_ctx;
25 struct drm_atomic_state *state;
26 int ret;
27
28 if (!HAS_DISPLAY(dev_priv))
29 return;
30
31 /* reset doesn't touch the display */
32 if (!dev_priv->display.params.force_reset_modeset_test &&
33 !gpu_reset_clobbers_display(dev_priv))
34 return;
35
36 /* We have a modeset vs reset deadlock, defensively unbreak it. */
37 set_bit(I915_RESET_MODESET, &to_gt(dev_priv)->reset.flags);
38 smp_mb__after_atomic();
39 wake_up_bit(&to_gt(dev_priv)->reset.flags, I915_RESET_MODESET);
40
41 if (atomic_read(&dev_priv->gpu_error.pending_fb_pin)) {
42 drm_dbg_kms(&dev_priv->drm,
43 "Modeset potentially stuck, unbreaking through wedging\n");
44 intel_gt_set_wedged(to_gt(dev_priv));
45 }
46
47 /*
48 * Need mode_config.mutex so that we don't
49 * trample ongoing ->detect() and whatnot.
50 */
51 mutex_lock(&dev_priv->drm.mode_config.mutex);
52 drm_modeset_acquire_init(ctx, 0);
53 while (1) {
54 ret = drm_modeset_lock_all_ctx(&dev_priv->drm, ctx);
55 if (ret != -EDEADLK)
56 break;
57
58 drm_modeset_backoff(ctx);
59 }
60 /*
61 * Disabling the crtcs gracefully seems nicer. Also the
62 * g33 docs say we should at least disable all the planes.
63 */
64 state = drm_atomic_helper_duplicate_state(&dev_priv->drm, ctx);
65 if (IS_ERR(state)) {
66 ret = PTR_ERR(state);
67 drm_err(&dev_priv->drm, "Duplicating state failed with %i\n",
68 ret);
69 return;
70 }
71
72 ret = drm_atomic_helper_disable_all(&dev_priv->drm, ctx);
73 if (ret) {
74 drm_err(&dev_priv->drm, "Suspending crtc's failed with %i\n",
75 ret);
76 drm_atomic_state_put(state);
77 return;
78 }
79
80 dev_priv->display.restore.modeset_state = state;
81 state->acquire_ctx = ctx;
82 }
83
intel_display_reset_finish(struct drm_i915_private * i915)84 void intel_display_reset_finish(struct drm_i915_private *i915)
85 {
86 struct intel_display *display = &i915->display;
87 struct drm_modeset_acquire_ctx *ctx = &display->restore.reset_ctx;
88 struct drm_atomic_state *state;
89 int ret;
90
91 if (!HAS_DISPLAY(i915))
92 return;
93
94 /* reset doesn't touch the display */
95 if (!test_bit(I915_RESET_MODESET, &to_gt(i915)->reset.flags))
96 return;
97
98 state = fetch_and_zero(&display->restore.modeset_state);
99 if (!state)
100 goto unlock;
101
102 /* reset doesn't touch the display */
103 if (!gpu_reset_clobbers_display(i915)) {
104 /* for testing only restore the display */
105 ret = drm_atomic_helper_commit_duplicated_state(state, ctx);
106 if (ret) {
107 drm_WARN_ON(&i915->drm, ret == -EDEADLK);
108 drm_err(&i915->drm,
109 "Restoring old state failed with %i\n", ret);
110 }
111 } else {
112 /*
113 * The display has been reset as well,
114 * so need a full re-initialization.
115 */
116 intel_pps_unlock_regs_wa(display);
117 intel_display_driver_init_hw(i915);
118 intel_clock_gating_init(i915);
119 intel_hpd_init(i915);
120
121 ret = __intel_display_driver_resume(i915, state, ctx);
122 if (ret)
123 drm_err(&i915->drm,
124 "Restoring old state failed with %i\n", ret);
125
126 intel_hpd_poll_disable(i915);
127 }
128
129 drm_atomic_state_put(state);
130 unlock:
131 drm_modeset_drop_locks(ctx);
132 drm_modeset_acquire_fini(ctx);
133 mutex_unlock(&i915->drm.mode_config.mutex);
134
135 clear_bit_unlock(I915_RESET_MODESET, &to_gt(i915)->reset.flags);
136 }
137