1 /* 2 * Copyright (C) 2014 Red Hat 3 * Author: Rob Clark <robdclark@gmail.com> 4 * 5 * This program is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 as published by 7 * the Free Software Foundation. 8 * 9 * This program is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 12 * more details. 13 * 14 * You should have received a copy of the GNU General Public License along with 15 * this program. If not, see <http://www.gnu.org/licenses/>. 16 */ 17 18 #include "msm_drv.h" 19 #include "msm_kms.h" 20 #include "msm_gem.h" 21 #include "msm_fence.h" 22 23 struct msm_commit { 24 struct drm_device *dev; 25 struct drm_atomic_state *state; 26 struct work_struct work; 27 uint32_t crtc_mask; 28 }; 29 30 static void commit_worker(struct work_struct *work); 31 32 /* block until specified crtcs are no longer pending update, and 33 * atomically mark them as pending update 34 */ 35 static int start_atomic(struct msm_drm_private *priv, uint32_t crtc_mask) 36 { 37 int ret; 38 39 spin_lock(&priv->pending_crtcs_event.lock); 40 ret = wait_event_interruptible_locked(priv->pending_crtcs_event, 41 !(priv->pending_crtcs & crtc_mask)); 42 if (ret == 0) { 43 DBG("start: %08x", crtc_mask); 44 priv->pending_crtcs |= crtc_mask; 45 } 46 spin_unlock(&priv->pending_crtcs_event.lock); 47 48 return ret; 49 } 50 51 /* clear specified crtcs (no longer pending update) 52 */ 53 static void end_atomic(struct msm_drm_private *priv, uint32_t crtc_mask) 54 { 55 spin_lock(&priv->pending_crtcs_event.lock); 56 DBG("end: %08x", crtc_mask); 57 priv->pending_crtcs &= ~crtc_mask; 58 wake_up_all_locked(&priv->pending_crtcs_event); 59 spin_unlock(&priv->pending_crtcs_event.lock); 60 } 61 62 static struct msm_commit *commit_init(struct drm_atomic_state *state) 63 { 64 struct msm_commit *c = kzalloc(sizeof(*c), GFP_KERNEL); 65 66 if (!c) 67 return NULL; 68 69 c->dev = state->dev; 70 c->state = state; 71 72 INIT_WORK(&c->work, commit_worker); 73 74 return c; 75 } 76 77 static void commit_destroy(struct msm_commit *c) 78 { 79 end_atomic(c->dev->dev_private, c->crtc_mask); 80 kfree(c); 81 } 82 83 static void msm_atomic_wait_for_commit_done(struct drm_device *dev, 84 struct drm_atomic_state *old_state) 85 { 86 struct drm_crtc *crtc; 87 struct drm_crtc_state *crtc_state; 88 struct msm_drm_private *priv = old_state->dev->dev_private; 89 struct msm_kms *kms = priv->kms; 90 int i; 91 92 for_each_crtc_in_state(old_state, crtc, crtc_state, i) { 93 if (!crtc->state->enable) 94 continue; 95 96 kms->funcs->wait_for_crtc_commit_done(kms, crtc); 97 } 98 } 99 100 /* The (potentially) asynchronous part of the commit. At this point 101 * nothing can fail short of armageddon. 102 */ 103 static void complete_commit(struct msm_commit *c, bool async) 104 { 105 struct drm_atomic_state *state = c->state; 106 struct drm_device *dev = state->dev; 107 struct msm_drm_private *priv = dev->dev_private; 108 struct msm_kms *kms = priv->kms; 109 110 drm_atomic_helper_wait_for_fences(dev, state, false); 111 112 kms->funcs->prepare_commit(kms, state); 113 114 drm_atomic_helper_commit_modeset_disables(dev, state); 115 116 drm_atomic_helper_commit_planes(dev, state, 0); 117 118 drm_atomic_helper_commit_modeset_enables(dev, state); 119 120 /* NOTE: _wait_for_vblanks() only waits for vblank on 121 * enabled CRTCs. So we end up faulting when disabling 122 * due to (potentially) unref'ing the outgoing fb's 123 * before the vblank when the disable has latched. 124 * 125 * But if it did wait on disabled (or newly disabled) 126 * CRTCs, that would be racy (ie. we could have missed 127 * the irq. We need some way to poll for pipe shut 128 * down. Or just live with occasionally hitting the 129 * timeout in the CRTC disable path (which really should 130 * not be critical path) 131 */ 132 133 msm_atomic_wait_for_commit_done(dev, state); 134 135 drm_atomic_helper_cleanup_planes(dev, state); 136 137 kms->funcs->complete_commit(kms, state); 138 139 drm_atomic_state_put(state); 140 141 commit_destroy(c); 142 } 143 144 static void commit_worker(struct work_struct *work) 145 { 146 complete_commit(container_of(work, struct msm_commit, work), true); 147 } 148 149 /* 150 * this func is identical to the drm_atomic_helper_check, but we keep this 151 * because we might eventually need to have a more finegrained check 152 * sequence without using the atomic helpers. 153 * 154 * In the past, we first called drm_atomic_helper_check_planes, and then 155 * drm_atomic_helper_check_modeset. We needed this because the MDP5 plane's 156 * ->atomic_check could update ->mode_changed for pixel format changes. 157 * This, however isn't needed now because if there is a pixel format change, 158 * we just assign a new hwpipe for it with a new SMP allocation. We might 159 * eventually hit a condition where we would need to do a full modeset if 160 * we run out of planes. There, we'd probably need to set mode_changed. 161 */ 162 int msm_atomic_check(struct drm_device *dev, 163 struct drm_atomic_state *state) 164 { 165 int ret; 166 167 ret = drm_atomic_helper_check_modeset(dev, state); 168 if (ret) 169 return ret; 170 171 ret = drm_atomic_helper_check_planes(dev, state); 172 if (ret) 173 return ret; 174 175 return ret; 176 } 177 178 /** 179 * drm_atomic_helper_commit - commit validated state object 180 * @dev: DRM device 181 * @state: the driver state object 182 * @nonblock: nonblocking commit 183 * 184 * This function commits a with drm_atomic_helper_check() pre-validated state 185 * object. This can still fail when e.g. the framebuffer reservation fails. 186 * 187 * RETURNS 188 * Zero for success or -errno. 189 */ 190 int msm_atomic_commit(struct drm_device *dev, 191 struct drm_atomic_state *state, bool nonblock) 192 { 193 struct msm_drm_private *priv = dev->dev_private; 194 struct msm_commit *c; 195 struct drm_crtc *crtc; 196 struct drm_crtc_state *crtc_state; 197 struct drm_plane *plane; 198 struct drm_plane_state *plane_state; 199 int i, ret; 200 201 ret = drm_atomic_helper_prepare_planes(dev, state); 202 if (ret) 203 return ret; 204 205 c = commit_init(state); 206 if (!c) { 207 ret = -ENOMEM; 208 goto error; 209 } 210 211 /* 212 * Figure out what crtcs we have: 213 */ 214 for_each_crtc_in_state(state, crtc, crtc_state, i) 215 c->crtc_mask |= drm_crtc_mask(crtc); 216 217 /* 218 * Figure out what fence to wait for: 219 */ 220 for_each_plane_in_state(state, plane, plane_state, i) { 221 if ((plane->state->fb != plane_state->fb) && plane_state->fb) { 222 struct drm_gem_object *obj = msm_framebuffer_bo(plane_state->fb, 0); 223 struct msm_gem_object *msm_obj = to_msm_bo(obj); 224 struct dma_fence *fence = reservation_object_get_excl_rcu(msm_obj->resv); 225 226 drm_atomic_set_fence_for_plane(plane_state, fence); 227 } 228 } 229 230 /* 231 * Wait for pending updates on any of the same crtc's and then 232 * mark our set of crtc's as busy: 233 */ 234 ret = start_atomic(dev->dev_private, c->crtc_mask); 235 if (ret) { 236 kfree(c); 237 goto error; 238 } 239 240 /* 241 * This is the point of no return - everything below never fails except 242 * when the hw goes bonghits. Which means we can commit the new state on 243 * the software side now. 244 */ 245 246 drm_atomic_helper_swap_state(state, true); 247 248 /* swap driver private state while still holding state_lock */ 249 if (to_kms_state(state)->state) 250 priv->kms->funcs->swap_state(priv->kms, state); 251 252 /* 253 * Everything below can be run asynchronously without the need to grab 254 * any modeset locks at all under one conditions: It must be guaranteed 255 * that the asynchronous work has either been cancelled (if the driver 256 * supports it, which at least requires that the framebuffers get 257 * cleaned up with drm_atomic_helper_cleanup_planes()) or completed 258 * before the new state gets committed on the software side with 259 * drm_atomic_helper_swap_state(). 260 * 261 * This scheme allows new atomic state updates to be prepared and 262 * checked in parallel to the asynchronous completion of the previous 263 * update. Which is important since compositors need to figure out the 264 * composition of the next frame right after having submitted the 265 * current layout. 266 */ 267 268 drm_atomic_state_get(state); 269 if (nonblock) { 270 queue_work(priv->atomic_wq, &c->work); 271 return 0; 272 } 273 274 complete_commit(c, false); 275 276 return 0; 277 278 error: 279 drm_atomic_helper_cleanup_planes(dev, state); 280 return ret; 281 } 282 283 struct drm_atomic_state *msm_atomic_state_alloc(struct drm_device *dev) 284 { 285 struct msm_kms_state *state = kzalloc(sizeof(*state), GFP_KERNEL); 286 287 if (!state || drm_atomic_state_init(dev, &state->base) < 0) { 288 kfree(state); 289 return NULL; 290 } 291 292 return &state->base; 293 } 294 295 void msm_atomic_state_clear(struct drm_atomic_state *s) 296 { 297 struct msm_kms_state *state = to_kms_state(s); 298 drm_atomic_state_default_clear(&state->base); 299 kfree(state->state); 300 state->state = NULL; 301 } 302 303 void msm_atomic_state_free(struct drm_atomic_state *state) 304 { 305 kfree(to_kms_state(state)->state); 306 drm_atomic_state_default_release(state); 307 kfree(state); 308 } 309