include/drm/drm_atomic.h

   1 /*
   2  * Copyright (C) 2014 Red Hat
   3  * Copyright (C) 2014 Intel Corp.
   4  *
   5  * Permission is hereby granted, free of charge, to any person obtaining a
   6  * copy of this software and associated documentation files (the "Software"),
   7  * to deal in the Software without restriction, including without limitation
   8  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   9  * and/or sell copies of the Software, and to permit persons to whom the
  10  * Software is furnished to do so, subject to the following conditions:
  11  *
  12  * The above copyright notice and this permission notice shall be included in
  13  * all copies or substantial portions of the Software.
  14  *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  18  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
  19  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  20  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  21  * OTHER DEALINGS IN THE SOFTWARE.
  22  *
  23  * Authors:
  24  * Rob Clark <robdclark@gmail.com>
  25  * Daniel Vetter <daniel.vetter@ffwll.ch>
  26  */
  27
  28 #ifndef DRM_ATOMIC_H_
  29 #define DRM_ATOMIC_H_
  30
  31 #include <drm/drm_crtc.h>
  32
  33 /**
  34  * struct drm_crtc_commit - track modeset commits on a CRTC
  35  *
  36  * This structure is used to track pending modeset changes and atomic commit on
  37  * a per-CRTC basis. Since updating the list should never block this structure
  38  * is reference counted to allow waiters to safely wait on an event to complete,
  39  * without holding any locks.
  40  *
  41  * It has 3 different events in total to allow a fine-grained synchronization
  42  * between outstanding updates::
  43  *
  44  *      atomic commit thread                    hardware
  45  *
  46  *      write new state into hardware   ---->   ...
  47  *      signal hw_done
  48  *                                              switch to new state on next
  49  *      ...                                     v/hblank
  50  *
  51  *      wait for buffers to show up             ...
  52  *
  53  *      ...                                     send completion irq
  54  *                                              irq handler signals flip_done
  55  *      cleanup old buffers
  56  *
  57  *      signal cleanup_done
  58  *
  59  *      wait for flip_done              <----
  60  *      clean up atomic state
  61  *
  62  * The important bit to know is that cleanup_done is the terminal event, but the
  63  * ordering between flip_done and hw_done is entirely up to the specific driver
  64  * and modeset state change.
  65  *
  66  * For an implementation of how to use this look at
  67  * drm_atomic_helper_setup_commit() from the atomic helper library.
  68  */
  69 struct drm_crtc_commit {
  70         /**
  71          * @crtc:
  72          *
  73          * DRM CRTC for this commit.
  74          */
  75         struct drm_crtc *crtc;
  76
  77         /**
  78          * @ref:
  79          *
  80          * Reference count for this structure. Needed to allow blocking on
  81          * completions without the risk of the completion disappearing
  82          * meanwhile.
  83          */
  84         struct kref ref;
  85
  86         /**
  87          * @flip_done:
  88          *
  89          * Will be signaled when the hardware has flipped to the new set of
  90          * buffers. Signals at the same time as when the drm event for this
  91          * commit is sent to userspace, or when an out-fence is singalled. Note
  92          * that for most hardware, in most cases this happens after @hw_done is
  93          * signalled.
  94          */
  95         struct completion flip_done;
  96
  97         /**
  98          * @hw_done:
  99          *
 100          * Will be signalled when all hw register changes for this commit have
 101          * been written out. Especially when disabling a pipe this can be much
 102          * later than than @flip_done, since that can signal already when the
 103          * screen goes black, whereas to fully shut down a pipe more register
 104          * I/O is required.
 105          *
 106          * Note that this does not need to include separately reference-counted
 107          * resources like backing storage buffer pinning, or runtime pm
 108          * management.
 109          */
 110         struct completion hw_done;
 111
 112         /**
 113          * @cleanup_done:
 114          *
 115          * Will be signalled after old buffers have been cleaned up by calling
 116          * drm_atomic_helper_cleanup_planes(). Since this can only happen after
 117          * a vblank wait completed it might be a bit later. This completion is
 118          * useful to throttle updates and avoid hardware updates getting ahead
 119          * of the buffer cleanup too much.
 120          */
 121         struct completion cleanup_done;
 122
 123         /**
 124          * @commit_entry:
 125          *
 126          * Entry on the per-CRTC commit_list. Protected by crtc->commit_lock.
 127          */
 128         struct list_head commit_entry;
 129
 130         /**
 131          * @event:
 132          *
 133          * &drm_pending_vblank_event pointer to clean up private events.
 134          */
 135         struct drm_pending_vblank_event *event;
 136 };
 137
 138 struct __drm_planes_state {
 139         struct drm_plane *ptr;
 140         struct drm_plane_state *state;
 141 };
 142
 143 struct __drm_crtcs_state {
 144         struct drm_crtc *ptr;
 145         struct drm_crtc_state *state;
 146         struct drm_crtc_commit *commit;
 147         s32 __user *out_fence_ptr;
 148 };
 149
 150 struct __drm_connnectors_state {
 151         struct drm_connector *ptr;
 152         struct drm_connector_state *state;
 153 };
 154
 155 /**
 156  * struct drm_atomic_state - the global state object for atomic updates
 157  * @ref: count of all references to this state (will not be freed until zero)
 158  * @dev: parent DRM device
 159  * @allow_modeset: allow full modeset
 160  * @legacy_cursor_update: hint to enforce legacy cursor IOCTL semantics
 161  * @legacy_set_config: Disable conflicting encoders instead of failing with -EINVAL.
 162  * @planes: pointer to array of structures with per-plane data
 163  * @crtcs: pointer to array of CRTC pointers
 164  * @num_connector: size of the @connectors and @connector_states arrays
 165  * @connectors: pointer to array of structures with per-connector data
 166  * @acquire_ctx: acquire context for this atomic modeset state update
 167  */
 168 struct drm_atomic_state {
 169         struct kref ref;
 170
 171         struct drm_device *dev;
 172         bool allow_modeset : 1;
 173         bool legacy_cursor_update : 1;
 174         bool legacy_set_config : 1;
 175         struct __drm_planes_state *planes;
 176         struct __drm_crtcs_state *crtcs;
 177         int num_connector;
 178         struct __drm_connnectors_state *connectors;
 179
 180         struct drm_modeset_acquire_ctx *acquire_ctx;
 181
 182         /**
 183          * @commit_work:
 184          *
 185          * Work item which can be used by the driver or helpers to execute the
 186          * commit without blocking.
 187          */
 188         struct work_struct commit_work;
 189 };
 190
 191 void drm_crtc_commit_put(struct drm_crtc_commit *commit);
 192 static inline void drm_crtc_commit_get(struct drm_crtc_commit *commit)
 193 {
 194         kref_get(&commit->ref);
 195 }
 196
 197 struct drm_atomic_state * __must_check
 198 drm_atomic_state_alloc(struct drm_device *dev);
 199 void drm_atomic_state_clear(struct drm_atomic_state *state);
 200
 201 /**
 202  * drm_atomic_state_get - acquire a reference to the atomic state
 203  * @state: The atomic state
 204  *
 205  * Returns a new reference to the @state
 206  */
 207 static inline struct drm_atomic_state *
 208 drm_atomic_state_get(struct drm_atomic_state *state)
 209 {
 210         kref_get(&state->ref);
 211         return state;
 212 }
 213
 214 void __drm_atomic_state_free(struct kref *ref);
 215
 216 /**
 217  * drm_atomic_state_put - release a reference to the atomic state
 218  * @state: The atomic state
 219  *
 220  * This releases a reference to @state which is freed after removing the
 221  * final reference. No locking required and callable from any context.
 222  */
 223 static inline void drm_atomic_state_put(struct drm_atomic_state *state)
 224 {
 225         kref_put(&state->ref, __drm_atomic_state_free);
 226 }
 227
 228 int  __must_check
 229 drm_atomic_state_init(struct drm_device *dev, struct drm_atomic_state *state);
 230 void drm_atomic_state_default_clear(struct drm_atomic_state *state);
 231 void drm_atomic_state_default_release(struct drm_atomic_state *state);
 232
 233 struct drm_crtc_state * __must_check
 234 drm_atomic_get_crtc_state(struct drm_atomic_state *state,
 235                           struct drm_crtc *crtc);
 236 int drm_atomic_crtc_set_property(struct drm_crtc *crtc,
 237                 struct drm_crtc_state *state, struct drm_property *property,
 238                 uint64_t val);
 239 struct drm_plane_state * __must_check
 240 drm_atomic_get_plane_state(struct drm_atomic_state *state,
 241                            struct drm_plane *plane);
 242 int drm_atomic_plane_set_property(struct drm_plane *plane,
 243                 struct drm_plane_state *state, struct drm_property *property,
 244                 uint64_t val);
 245 struct drm_connector_state * __must_check
 246 drm_atomic_get_connector_state(struct drm_atomic_state *state,
 247                                struct drm_connector *connector);
 248 int drm_atomic_connector_set_property(struct drm_connector *connector,
 249                 struct drm_connector_state *state, struct drm_property *property,
 250                 uint64_t val);
 251
 252 /**
 253  * drm_atomic_get_existing_crtc_state - get crtc state, if it exists
 254  * @state: global atomic state object
 255  * @crtc: crtc to grab
 256  *
 257  * This function returns the crtc state for the given crtc, or NULL
 258  * if the crtc is not part of the global atomic state.
 259  */
 260 static inline struct drm_crtc_state *
 261 drm_atomic_get_existing_crtc_state(struct drm_atomic_state *state,
 262                                    struct drm_crtc *crtc)
 263 {
 264         return state->crtcs[drm_crtc_index(crtc)].state;
 265 }
 266
 267 /**
 268  * drm_atomic_get_existing_plane_state - get plane state, if it exists
 269  * @state: global atomic state object
 270  * @plane: plane to grab
 271  *
 272  * This function returns the plane state for the given plane, or NULL
 273  * if the plane is not part of the global atomic state.
 274  */
 275 static inline struct drm_plane_state *
 276 drm_atomic_get_existing_plane_state(struct drm_atomic_state *state,
 277                                     struct drm_plane *plane)
 278 {
 279         return state->planes[drm_plane_index(plane)].state;
 280 }
 281
 282 /**
 283  * drm_atomic_get_existing_connector_state - get connector state, if it exists
 284  * @state: global atomic state object
 285  * @connector: connector to grab
 286  *
 287  * This function returns the connector state for the given connector,
 288  * or NULL if the connector is not part of the global atomic state.
 289  */
 290 static inline struct drm_connector_state *
 291 drm_atomic_get_existing_connector_state(struct drm_atomic_state *state,
 292                                         struct drm_connector *connector)
 293 {
 294         int index = drm_connector_index(connector);
 295
 296         if (index >= state->num_connector)
 297                 return NULL;
 298
 299         return state->connectors[index].state;
 300 }
 301
 302 /**
 303  * __drm_atomic_get_current_plane_state - get current plane state
 304  * @state: global atomic state object
 305  * @plane: plane to grab
 306  *
 307  * This function returns the plane state for the given plane, either from
 308  * @state, or if the plane isn't part of the atomic state update, from @plane.
 309  * This is useful in atomic check callbacks, when drivers need to peek at, but
 310  * not change, state of other planes, since it avoids threading an error code
 311  * back up the call chain.
 312  *
 313  * WARNING:
 314  *
 315  * Note that this function is in general unsafe since it doesn't check for the
 316  * required locking for access state structures. Drivers must ensure that it is
 317  * safe to access the returned state structure through other means. One common
 318  * example is when planes are fixed to a single CRTC, and the driver knows that
 319  * the CRTC lock is held already. In that case holding the CRTC lock gives a
 320  * read-lock on all planes connected to that CRTC. But if planes can be
 321  * reassigned things get more tricky. In that case it's better to use
 322  * drm_atomic_get_plane_state and wire up full error handling.
 323  *
 324  * Returns:
 325  *
 326  * Read-only pointer to the current plane state.
 327  */
 328 static inline const struct drm_plane_state *
 329 __drm_atomic_get_current_plane_state(struct drm_atomic_state *state,
 330                                      struct drm_plane *plane)
 331 {
 332         if (state->planes[drm_plane_index(plane)].state)
 333                 return state->planes[drm_plane_index(plane)].state;
 334
 335         return plane->state;
 336 }
 337
 338 int __must_check
 339 drm_atomic_set_mode_for_crtc(struct drm_crtc_state *state,
 340                              struct drm_display_mode *mode);
 341 int __must_check
 342 drm_atomic_set_mode_prop_for_crtc(struct drm_crtc_state *state,
 343                                   struct drm_property_blob *blob);
 344 int __must_check
 345 drm_atomic_set_crtc_for_plane(struct drm_plane_state *plane_state,
 346                               struct drm_crtc *crtc);
 347 void drm_atomic_set_fb_for_plane(struct drm_plane_state *plane_state,
 348                                  struct drm_framebuffer *fb);
 349 void drm_atomic_set_fence_for_plane(struct drm_plane_state *plane_state,
 350                                     struct dma_fence *fence);
 351 int __must_check
 352 drm_atomic_set_crtc_for_connector(struct drm_connector_state *conn_state,
 353                                   struct drm_crtc *crtc);
 354 int __must_check
 355 drm_atomic_add_affected_connectors(struct drm_atomic_state *state,
 356                                    struct drm_crtc *crtc);
 357 int __must_check
 358 drm_atomic_add_affected_planes(struct drm_atomic_state *state,
 359                                struct drm_crtc *crtc);
 360
 361 void drm_atomic_legacy_backoff(struct drm_atomic_state *state);
 362
 363 void
 364 drm_atomic_clean_old_fb(struct drm_device *dev, unsigned plane_mask, int ret);
 365
 366 int __must_check drm_atomic_check_only(struct drm_atomic_state *state);
 367 int __must_check drm_atomic_commit(struct drm_atomic_state *state);
 368 int __must_check drm_atomic_nonblocking_commit(struct drm_atomic_state *state);
 369
 370 void drm_state_dump(struct drm_device *dev, struct drm_printer *p);
 371
 372 #ifdef CONFIG_DEBUG_FS
 373 struct drm_minor;
 374 int drm_atomic_debugfs_init(struct drm_minor *minor);
 375 int drm_atomic_debugfs_cleanup(struct drm_minor *minor);
 376 #endif
 377
 378 #define for_each_connector_in_state(__state, connector, connector_state, __i) \
 379         for ((__i) = 0;                                                 \
 380              (__i) < (__state)->num_connector &&                                \
 381              ((connector) = (__state)->connectors[__i].ptr,                     \
 382              (connector_state) = (__state)->connectors[__i].state, 1);  \
 383              (__i)++)                                                   \
 384                 for_each_if (connector)
 385
 386 #define for_each_crtc_in_state(__state, crtc, crtc_state, __i)  \
 387         for ((__i) = 0;                                         \
 388              (__i) < (__state)->dev->mode_config.num_crtc &&    \
 389              ((crtc) = (__state)->crtcs[__i].ptr,                       \
 390              (crtc_state) = (__state)->crtcs[__i].state, 1);    \
 391              (__i)++)                                           \
 392                 for_each_if (crtc_state)
 393
 394 #define for_each_plane_in_state(__state, plane, plane_state, __i)               \
 395         for ((__i) = 0;                                                 \
 396              (__i) < (__state)->dev->mode_config.num_total_plane &&     \
 397              ((plane) = (__state)->planes[__i].ptr,                             \
 398              (plane_state) = (__state)->planes[__i].state, 1);          \
 399              (__i)++)                                                   \
 400                 for_each_if (plane_state)
 401
 402 /**
 403  * drm_atomic_crtc_needs_modeset - compute combined modeset need
 404  * @state: &drm_crtc_state for the CRTC
 405  *
 406  * To give drivers flexibility struct &drm_crtc_state has 3 booleans to track
 407  * whether the state CRTC changed enough to need a full modeset cycle:
 408  * connectors_changed, mode_changed and active_changed. This helper simply
 409  * combines these three to compute the overall need for a modeset for @state.
 410  *
 411  * The atomic helper code sets these booleans, but drivers can and should
 412  * change them appropriately to accurately represent whether a modeset is
 413  * really needed. In general, drivers should avoid full modesets whenever
 414  * possible.
 415  *
 416  * For example if the CRTC mode has changed, and the hardware is able to enact
 417  * the requested mode change without going through a full modeset, the driver
 418  * should clear mode_changed during its ->atomic_check.
 419  */
 420 static inline bool
 421 drm_atomic_crtc_needs_modeset(const struct drm_crtc_state *state)
 422 {
 423         return state->mode_changed || state->active_changed ||
 424                state->connectors_changed;
 425 }
 426
 427
 428 #endif /* DRM_ATOMIC_H_ */