1 /*
2 * Copyright (C) 2015 Broadcom
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2 as
6 * published by the Free Software Foundation.
7 */
8
9 /**
10 * DOC: VC4 KMS
11 *
12 * This is the general code for implementing KMS mode setting that
13 * doesn't clearly associate with any of the other objects (plane,
14 * crtc, HDMI encoder).
15 */
16
17 #include <drm/drm_crtc.h>
18 #include <drm/drm_atomic.h>
19 #include <drm/drm_atomic_helper.h>
20 #include <drm/drm_crtc_helper.h>
21 #include <drm/drm_plane_helper.h>
22 #include <drm/drm_fb_cma_helper.h>
23 #include <drm/drm_gem_framebuffer_helper.h>
24 #include "vc4_drv.h"
25
vc4_output_poll_changed(struct drm_device * dev)26 static void vc4_output_poll_changed(struct drm_device *dev)
27 {
28 struct vc4_dev *vc4 = to_vc4_dev(dev);
29
30 drm_fbdev_cma_hotplug_event(vc4->fbdev);
31 }
32
33 static void
vc4_atomic_complete_commit(struct drm_atomic_state * state)34 vc4_atomic_complete_commit(struct drm_atomic_state *state)
35 {
36 struct drm_device *dev = state->dev;
37 struct vc4_dev *vc4 = to_vc4_dev(dev);
38
39 drm_atomic_helper_wait_for_fences(dev, state, false);
40
41 drm_atomic_helper_wait_for_dependencies(state);
42
43 drm_atomic_helper_commit_modeset_disables(dev, state);
44
45 drm_atomic_helper_commit_planes(dev, state, 0);
46
47 drm_atomic_helper_commit_modeset_enables(dev, state);
48
49 /* Make sure that drm_atomic_helper_wait_for_vblanks()
50 * actually waits for vblank. If we're doing a full atomic
51 * modeset (as opposed to a vc4_update_plane() short circuit),
52 * then we need to wait for scanout to be done with our
53 * display lists before we free it and potentially reallocate
54 * and overwrite the dlist memory with a new modeset.
55 */
56 state->legacy_cursor_update = false;
57
58 drm_atomic_helper_commit_hw_done(state);
59
60 drm_atomic_helper_wait_for_vblanks(dev, state);
61
62 drm_atomic_helper_cleanup_planes(dev, state);
63
64 drm_atomic_helper_commit_cleanup_done(state);
65
66 drm_atomic_state_put(state);
67
68 up(&vc4->async_modeset);
69 }
70
commit_work(struct work_struct * work)71 static void commit_work(struct work_struct *work)
72 {
73 struct drm_atomic_state *state = container_of(work,
74 struct drm_atomic_state,
75 commit_work);
76 vc4_atomic_complete_commit(state);
77 }
78
79 /**
80 * vc4_atomic_commit - commit validated state object
81 * @dev: DRM device
82 * @state: the driver state object
83 * @nonblock: nonblocking commit
84 *
85 * This function commits a with drm_atomic_helper_check() pre-validated state
86 * object. This can still fail when e.g. the framebuffer reservation fails. For
87 * now this doesn't implement asynchronous commits.
88 *
89 * RETURNS
90 * Zero for success or -errno.
91 */
vc4_atomic_commit(struct drm_device * dev,struct drm_atomic_state * state,bool nonblock)92 static int vc4_atomic_commit(struct drm_device *dev,
93 struct drm_atomic_state *state,
94 bool nonblock)
95 {
96 struct vc4_dev *vc4 = to_vc4_dev(dev);
97 int ret;
98
99 ret = drm_atomic_helper_setup_commit(state, nonblock);
100 if (ret)
101 return ret;
102
103 INIT_WORK(&state->commit_work, commit_work);
104
105 ret = down_interruptible(&vc4->async_modeset);
106 if (ret)
107 return ret;
108
109 ret = drm_atomic_helper_prepare_planes(dev, state);
110 if (ret) {
111 up(&vc4->async_modeset);
112 return ret;
113 }
114
115 if (!nonblock) {
116 ret = drm_atomic_helper_wait_for_fences(dev, state, true);
117 if (ret) {
118 drm_atomic_helper_cleanup_planes(dev, state);
119 up(&vc4->async_modeset);
120 return ret;
121 }
122 }
123
124 /*
125 * This is the point of no return - everything below never fails except
126 * when the hw goes bonghits. Which means we can commit the new state on
127 * the software side now.
128 */
129
130 BUG_ON(drm_atomic_helper_swap_state(state, false) < 0);
131
132 /*
133 * Everything below can be run asynchronously without the need to grab
134 * any modeset locks at all under one condition: It must be guaranteed
135 * that the asynchronous work has either been cancelled (if the driver
136 * supports it, which at least requires that the framebuffers get
137 * cleaned up with drm_atomic_helper_cleanup_planes()) or completed
138 * before the new state gets committed on the software side with
139 * drm_atomic_helper_swap_state().
140 *
141 * This scheme allows new atomic state updates to be prepared and
142 * checked in parallel to the asynchronous completion of the previous
143 * update. Which is important since compositors need to figure out the
144 * composition of the next frame right after having submitted the
145 * current layout.
146 */
147
148 drm_atomic_state_get(state);
149 if (nonblock)
150 queue_work(system_unbound_wq, &state->commit_work);
151 else
152 vc4_atomic_complete_commit(state);
153
154 return 0;
155 }
156
vc4_fb_create(struct drm_device * dev,struct drm_file * file_priv,const struct drm_mode_fb_cmd2 * mode_cmd)157 static struct drm_framebuffer *vc4_fb_create(struct drm_device *dev,
158 struct drm_file *file_priv,
159 const struct drm_mode_fb_cmd2 *mode_cmd)
160 {
161 struct drm_mode_fb_cmd2 mode_cmd_local;
162
163 /* If the user didn't specify a modifier, use the
164 * vc4_set_tiling_ioctl() state for the BO.
165 */
166 if (!(mode_cmd->flags & DRM_MODE_FB_MODIFIERS)) {
167 struct drm_gem_object *gem_obj;
168 struct vc4_bo *bo;
169
170 gem_obj = drm_gem_object_lookup(file_priv,
171 mode_cmd->handles[0]);
172 if (!gem_obj) {
173 DRM_DEBUG("Failed to look up GEM BO %d\n",
174 mode_cmd->handles[0]);
175 return ERR_PTR(-ENOENT);
176 }
177 bo = to_vc4_bo(gem_obj);
178
179 mode_cmd_local = *mode_cmd;
180
181 if (bo->t_format) {
182 mode_cmd_local.modifier[0] =
183 DRM_FORMAT_MOD_BROADCOM_VC4_T_TILED;
184 } else {
185 mode_cmd_local.modifier[0] = DRM_FORMAT_MOD_NONE;
186 }
187
188 drm_gem_object_put_unlocked(gem_obj);
189
190 mode_cmd = &mode_cmd_local;
191 }
192
193 return drm_gem_fb_create(dev, file_priv, mode_cmd);
194 }
195
196 static const struct drm_mode_config_funcs vc4_mode_funcs = {
197 .output_poll_changed = vc4_output_poll_changed,
198 .atomic_check = drm_atomic_helper_check,
199 .atomic_commit = vc4_atomic_commit,
200 .fb_create = vc4_fb_create,
201 };
202
vc4_kms_load(struct drm_device * dev)203 int vc4_kms_load(struct drm_device *dev)
204 {
205 struct vc4_dev *vc4 = to_vc4_dev(dev);
206 int ret;
207
208 sema_init(&vc4->async_modeset, 1);
209
210 /* Set support for vblank irq fast disable, before drm_vblank_init() */
211 dev->vblank_disable_immediate = true;
212
213 ret = drm_vblank_init(dev, dev->mode_config.num_crtc);
214 if (ret < 0) {
215 dev_err(dev->dev, "failed to initialize vblank\n");
216 return ret;
217 }
218
219 dev->mode_config.max_width = 2048;
220 dev->mode_config.max_height = 2048;
221 dev->mode_config.funcs = &vc4_mode_funcs;
222 dev->mode_config.preferred_depth = 24;
223 dev->mode_config.async_page_flip = true;
224
225 drm_mode_config_reset(dev);
226
227 if (dev->mode_config.num_connector) {
228 vc4->fbdev = drm_fbdev_cma_init(dev, 32,
229 dev->mode_config.num_connector);
230 if (IS_ERR(vc4->fbdev))
231 vc4->fbdev = NULL;
232 }
233
234 drm_kms_helper_poll_init(dev);
235
236 return 0;
237 }
238