drivers/gpu/drm/drm_fb_helper.c

   1 /*
   2  * Copyright (c) 2006-2009 Red Hat Inc.
   3  * Copyright (c) 2006-2008 Intel Corporation
   4  * Copyright (c) 2007 Dave Airlie <airlied@linux.ie>
   5  *
   6  * DRM framebuffer helper functions
   7  *
   8  * Permission to use, copy, modify, distribute, and sell this software and its
   9  * documentation for any purpose is hereby granted without fee, provided that
  10  * the above copyright notice appear in all copies and that both that copyright
  11  * notice and this permission notice appear in supporting documentation, and
  12  * that the name of the copyright holders not be used in advertising or
  13  * publicity pertaining to distribution of the software without specific,
  14  * written prior permission.  The copyright holders make no representations
  15  * about the suitability of this software for any purpose.  It is provided "as
  16  * is" without express or implied warranty.
  17  *
  18  * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
  19  * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
  20  * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
  21  * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
  22  * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
  23  * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
  24  * OF THIS SOFTWARE.
  25  *
  26  * Authors:
  27  *      Dave Airlie <airlied@linux.ie>
  28  *      Jesse Barnes <jesse.barnes@intel.com>
  29  */
  30 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  31
  32 #include <linux/kernel.h>
  33 #include <linux/sysrq.h>
  34 #include <linux/slab.h>
  35 #include <linux/fb.h>
  36 #include <linux/module.h>
  37 #include <drm/drmP.h>
  38 #include <drm/drm_crtc.h>
  39 #include <drm/drm_fb_helper.h>
  40 #include <drm/drm_crtc_helper.h>
  41 #include <drm/drm_atomic.h>
  42 #include <drm/drm_atomic_helper.h>
  43
  44 static bool drm_fbdev_emulation = true;
  45 module_param_named(fbdev_emulation, drm_fbdev_emulation, bool, 0600);
  46 MODULE_PARM_DESC(fbdev_emulation,
  47                  "Enable legacy fbdev emulation [default=true]");
  48
  49 static LIST_HEAD(kernel_fb_helper_list);
  50
  51 /**
  52  * DOC: fbdev helpers
  53  *
  54  * The fb helper functions are useful to provide an fbdev on top of a drm kernel
  55  * mode setting driver. They can be used mostly independently from the crtc
  56  * helper functions used by many drivers to implement the kernel mode setting
  57  * interfaces.
  58  *
  59  * Initialization is done as a four-step process with drm_fb_helper_prepare(),
  60  * drm_fb_helper_init(), drm_fb_helper_single_add_all_connectors() and
  61  * drm_fb_helper_initial_config(). Drivers with fancier requirements than the
  62  * default behaviour can override the third step with their own code.
  63  * Teardown is done with drm_fb_helper_fini().
  64  *
  65  * At runtime drivers should restore the fbdev console by calling
  66  * drm_fb_helper_restore_fbdev_mode_unlocked() from their ->lastclose callback.
  67  * They should also notify the fb helper code from updates to the output
  68  * configuration by calling drm_fb_helper_hotplug_event(). For easier
  69  * integration with the output polling code in drm_crtc_helper.c the modeset
  70  * code provides a ->output_poll_changed callback.
  71  *
  72  * All other functions exported by the fb helper library can be used to
  73  * implement the fbdev driver interface by the driver.
  74  *
  75  * It is possible, though perhaps somewhat tricky, to implement race-free
  76  * hotplug detection using the fbdev helpers. The drm_fb_helper_prepare()
  77  * helper must be called first to initialize the minimum required to make
  78  * hotplug detection work. Drivers also need to make sure to properly set up
  79  * the dev->mode_config.funcs member. After calling drm_kms_helper_poll_init()
  80  * it is safe to enable interrupts and start processing hotplug events. At the
  81  * same time, drivers should initialize all modeset objects such as CRTCs,
  82  * encoders and connectors. To finish up the fbdev helper initialization, the
  83  * drm_fb_helper_init() function is called. To probe for all attached displays
  84  * and set up an initial configuration using the detected hardware, drivers
  85  * should call drm_fb_helper_single_add_all_connectors() followed by
  86  * drm_fb_helper_initial_config().
  87  *
  88  * If &drm_framebuffer_funcs ->dirty is set, the
  89  * drm_fb_helper_{cfb,sys}_{write,fillrect,copyarea,imageblit} functions will
  90  * accumulate changes and schedule &drm_fb_helper ->dirty_work to run right
  91  * away. This worker then calls the dirty() function ensuring that it will
  92  * always run in process context since the fb_*() function could be running in
  93  * atomic context. If drm_fb_helper_deferred_io() is used as the deferred_io
  94  * callback it will also schedule dirty_work with the damage collected from the
  95  * mmap page writes.
  96  */
  97
  98 /**
  99  * drm_fb_helper_single_add_all_connectors() - add all connectors to fbdev
 100  *                                             emulation helper
 101  * @fb_helper: fbdev initialized with drm_fb_helper_init
 102  *
 103  * This functions adds all the available connectors for use with the given
 104  * fb_helper. This is a separate step to allow drivers to freely assign
 105  * connectors to the fbdev, e.g. if some are reserved for special purposes or
 106  * not adequate to be used for the fbcon.
 107  *
 108  * This function is protected against concurrent connector hotadds/removals
 109  * using drm_fb_helper_add_one_connector() and
 110  * drm_fb_helper_remove_one_connector().
 111  */
 112 int drm_fb_helper_single_add_all_connectors(struct drm_fb_helper *fb_helper)
 113 {
 114         struct drm_device *dev = fb_helper->dev;
 115         struct drm_connector *connector;
 116         int i, ret;
 117
 118         if (!drm_fbdev_emulation)
 119                 return 0;
 120
 121         mutex_lock(&dev->mode_config.mutex);
 122         drm_for_each_connector(connector, dev) {
 123                 ret = drm_fb_helper_add_one_connector(fb_helper, connector);
 124
 125                 if (ret)
 126                         goto fail;
 127         }
 128         mutex_unlock(&dev->mode_config.mutex);
 129         return 0;
 130 fail:
 131         for (i = 0; i < fb_helper->connector_count; i++) {
 132                 kfree(fb_helper->connector_info[i]);
 133                 fb_helper->connector_info[i] = NULL;
 134         }
 135         fb_helper->connector_count = 0;
 136         mutex_unlock(&dev->mode_config.mutex);
 137
 138         return ret;
 139 }
 140 EXPORT_SYMBOL(drm_fb_helper_single_add_all_connectors);
 141
 142 int drm_fb_helper_add_one_connector(struct drm_fb_helper *fb_helper, struct drm_connector *connector)
 143 {
 144         struct drm_fb_helper_connector **temp;
 145         struct drm_fb_helper_connector *fb_helper_connector;
 146
 147         if (!drm_fbdev_emulation)
 148                 return 0;
 149
 150         WARN_ON(!mutex_is_locked(&fb_helper->dev->mode_config.mutex));
 151         if (fb_helper->connector_count + 1 > fb_helper->connector_info_alloc_count) {
 152                 temp = krealloc(fb_helper->connector_info, sizeof(struct drm_fb_helper_connector *) * (fb_helper->connector_count + 1), GFP_KERNEL);
 153                 if (!temp)
 154                         return -ENOMEM;
 155
 156                 fb_helper->connector_info_alloc_count = fb_helper->connector_count + 1;
 157                 fb_helper->connector_info = temp;
 158         }
 159
 160
 161         fb_helper_connector = kzalloc(sizeof(struct drm_fb_helper_connector), GFP_KERNEL);
 162         if (!fb_helper_connector)
 163                 return -ENOMEM;
 164
 165         drm_connector_reference(connector);
 166         fb_helper_connector->connector = connector;
 167         fb_helper->connector_info[fb_helper->connector_count++] = fb_helper_connector;
 168         return 0;
 169 }
 170 EXPORT_SYMBOL(drm_fb_helper_add_one_connector);
 171
 172 int drm_fb_helper_remove_one_connector(struct drm_fb_helper *fb_helper,
 173                                        struct drm_connector *connector)
 174 {
 175         struct drm_fb_helper_connector *fb_helper_connector;
 176         int i, j;
 177
 178         if (!drm_fbdev_emulation)
 179                 return 0;
 180
 181         WARN_ON(!mutex_is_locked(&fb_helper->dev->mode_config.mutex));
 182
 183         for (i = 0; i < fb_helper->connector_count; i++) {
 184                 if (fb_helper->connector_info[i]->connector == connector)
 185                         break;
 186         }
 187
 188         if (i == fb_helper->connector_count)
 189                 return -EINVAL;
 190         fb_helper_connector = fb_helper->connector_info[i];
 191         drm_connector_unreference(fb_helper_connector->connector);
 192
 193         for (j = i + 1; j < fb_helper->connector_count; j++) {
 194                 fb_helper->connector_info[j - 1] = fb_helper->connector_info[j];
 195         }
 196         fb_helper->connector_count--;
 197         kfree(fb_helper_connector);
 198
 199         return 0;
 200 }
 201 EXPORT_SYMBOL(drm_fb_helper_remove_one_connector);
 202
 203 static void drm_fb_helper_save_lut_atomic(struct drm_crtc *crtc, struct drm_fb_helper *helper)
 204 {
 205         uint16_t *r_base, *g_base, *b_base;
 206         int i;
 207
 208         if (helper->funcs->gamma_get == NULL)
 209                 return;
 210
 211         r_base = crtc->gamma_store;
 212         g_base = r_base + crtc->gamma_size;
 213         b_base = g_base + crtc->gamma_size;
 214
 215         for (i = 0; i < crtc->gamma_size; i++)
 216                 helper->funcs->gamma_get(crtc, &r_base[i], &g_base[i], &b_base[i], i);
 217 }
 218
 219 static void drm_fb_helper_restore_lut_atomic(struct drm_crtc *crtc)
 220 {
 221         uint16_t *r_base, *g_base, *b_base;
 222
 223         if (crtc->funcs->gamma_set == NULL)
 224                 return;
 225
 226         r_base = crtc->gamma_store;
 227         g_base = r_base + crtc->gamma_size;
 228         b_base = g_base + crtc->gamma_size;
 229
 230         crtc->funcs->gamma_set(crtc, r_base, g_base, b_base, crtc->gamma_size);
 231 }
 232
 233 /**
 234  * drm_fb_helper_debug_enter - implementation for ->fb_debug_enter
 235  * @info: fbdev registered by the helper
 236  */
 237 int drm_fb_helper_debug_enter(struct fb_info *info)
 238 {
 239         struct drm_fb_helper *helper = info->par;
 240         const struct drm_crtc_helper_funcs *funcs;
 241         int i;
 242
 243         list_for_each_entry(helper, &kernel_fb_helper_list, kernel_fb_list) {
 244                 for (i = 0; i < helper->crtc_count; i++) {
 245                         struct drm_mode_set *mode_set =
 246                                 &helper->crtc_info[i].mode_set;
 247
 248                         if (!mode_set->crtc->enabled)
 249                                 continue;
 250
 251                         funcs = mode_set->crtc->helper_private;
 252                         drm_fb_helper_save_lut_atomic(mode_set->crtc, helper);
 253                         funcs->mode_set_base_atomic(mode_set->crtc,
 254                                                     mode_set->fb,
 255                                                     mode_set->x,
 256                                                     mode_set->y,
 257                                                     ENTER_ATOMIC_MODE_SET);
 258                 }
 259         }
 260
 261         return 0;
 262 }
 263 EXPORT_SYMBOL(drm_fb_helper_debug_enter);
 264
 265 /* Find the real fb for a given fb helper CRTC */
 266 static struct drm_framebuffer *drm_mode_config_fb(struct drm_crtc *crtc)
 267 {
 268         struct drm_device *dev = crtc->dev;
 269         struct drm_crtc *c;
 270
 271         drm_for_each_crtc(c, dev) {
 272                 if (crtc->base.id == c->base.id)
 273                         return c->primary->fb;
 274         }
 275
 276         return NULL;
 277 }
 278
 279 /**
 280  * drm_fb_helper_debug_leave - implementation for ->fb_debug_leave
 281  * @info: fbdev registered by the helper
 282  */
 283 int drm_fb_helper_debug_leave(struct fb_info *info)
 284 {
 285         struct drm_fb_helper *helper = info->par;
 286         struct drm_crtc *crtc;
 287         const struct drm_crtc_helper_funcs *funcs;
 288         struct drm_framebuffer *fb;
 289         int i;
 290
 291         for (i = 0; i < helper->crtc_count; i++) {
 292                 struct drm_mode_set *mode_set = &helper->crtc_info[i].mode_set;
 293                 crtc = mode_set->crtc;
 294                 funcs = crtc->helper_private;
 295                 fb = drm_mode_config_fb(crtc);
 296
 297                 if (!crtc->enabled)
 298                         continue;
 299
 300                 if (!fb) {
 301                         DRM_ERROR("no fb to restore??\n");
 302                         continue;
 303                 }
 304
 305                 drm_fb_helper_restore_lut_atomic(mode_set->crtc);
 306                 funcs->mode_set_base_atomic(mode_set->crtc, fb, crtc->x,
 307                                             crtc->y, LEAVE_ATOMIC_MODE_SET);
 308         }
 309
 310         return 0;
 311 }
 312 EXPORT_SYMBOL(drm_fb_helper_debug_leave);
 313
 314 static int restore_fbdev_mode_atomic(struct drm_fb_helper *fb_helper)
 315 {
 316         struct drm_device *dev = fb_helper->dev;
 317         struct drm_plane *plane;
 318         struct drm_atomic_state *state;
 319         int i, ret;
 320         unsigned plane_mask;
 321
 322         state = drm_atomic_state_alloc(dev);
 323         if (!state)
 324                 return -ENOMEM;
 325
 326         state->acquire_ctx = dev->mode_config.acquire_ctx;
 327 retry:
 328         plane_mask = 0;
 329         drm_for_each_plane(plane, dev) {
 330                 struct drm_plane_state *plane_state;
 331
 332                 plane_state = drm_atomic_get_plane_state(state, plane);
 333                 if (IS_ERR(plane_state)) {
 334                         ret = PTR_ERR(plane_state);
 335                         goto fail;
 336                 }
 337
 338                 plane_state->rotation = BIT(DRM_ROTATE_0);
 339
 340                 plane->old_fb = plane->fb;
 341                 plane_mask |= 1 << drm_plane_index(plane);
 342
 343                 /* disable non-primary: */
 344                 if (plane->type == DRM_PLANE_TYPE_PRIMARY)
 345                         continue;
 346
 347                 ret = __drm_atomic_helper_disable_plane(plane, plane_state);
 348                 if (ret != 0)
 349                         goto fail;
 350         }
 351
 352         for(i = 0; i < fb_helper->crtc_count; i++) {
 353                 struct drm_mode_set *mode_set = &fb_helper->crtc_info[i].mode_set;
 354
 355                 ret = __drm_atomic_helper_set_config(mode_set, state);
 356                 if (ret != 0)
 357                         goto fail;
 358         }
 359
 360         ret = drm_atomic_commit(state);
 361
 362 fail:
 363         drm_atomic_clean_old_fb(dev, plane_mask, ret);
 364
 365         if (ret == -EDEADLK)
 366                 goto backoff;
 367
 368         if (ret != 0)
 369                 drm_atomic_state_free(state);
 370
 371         return ret;
 372
 373 backoff:
 374         drm_atomic_state_clear(state);
 375         drm_atomic_legacy_backoff(state);
 376
 377         goto retry;
 378 }
 379
 380 static int restore_fbdev_mode(struct drm_fb_helper *fb_helper)
 381 {
 382         struct drm_device *dev = fb_helper->dev;
 383         struct drm_plane *plane;
 384         int i;
 385
 386         drm_warn_on_modeset_not_all_locked(dev);
 387
 388         if (dev->mode_config.funcs->atomic_commit)
 389                 return restore_fbdev_mode_atomic(fb_helper);
 390
 391         drm_for_each_plane(plane, dev) {
 392                 if (plane->type != DRM_PLANE_TYPE_PRIMARY)
 393                         drm_plane_force_disable(plane);
 394
 395                 if (dev->mode_config.rotation_property) {
 396                         drm_mode_plane_set_obj_prop(plane,
 397                                                     dev->mode_config.rotation_property,
 398                                                     BIT(DRM_ROTATE_0));
 399                 }
 400         }
 401
 402         for (i = 0; i < fb_helper->crtc_count; i++) {
 403                 struct drm_mode_set *mode_set = &fb_helper->crtc_info[i].mode_set;
 404                 struct drm_crtc *crtc = mode_set->crtc;
 405                 int ret;
 406
 407                 if (crtc->funcs->cursor_set2) {
 408                         ret = crtc->funcs->cursor_set2(crtc, NULL, 0, 0, 0, 0, 0);
 409                         if (ret)
 410                                 return ret;
 411                 } else if (crtc->funcs->cursor_set) {
 412                         ret = crtc->funcs->cursor_set(crtc, NULL, 0, 0, 0);
 413                         if (ret)
 414                                 return ret;
 415                 }
 416
 417                 ret = drm_mode_set_config_internal(mode_set);
 418                 if (ret)
 419                         return ret;
 420         }
 421
 422         return 0;
 423 }
 424
 425 /**
 426  * drm_fb_helper_restore_fbdev_mode_unlocked - restore fbdev configuration
 427  * @fb_helper: fbcon to restore
 428  *
 429  * This should be called from driver's drm ->lastclose callback
 430  * when implementing an fbcon on top of kms using this helper. This ensures that
 431  * the user isn't greeted with a black screen when e.g. X dies.
 432  *
 433  * RETURNS:
 434  * Zero if everything went ok, negative error code otherwise.
 435  */
 436 int drm_fb_helper_restore_fbdev_mode_unlocked(struct drm_fb_helper *fb_helper)
 437 {
 438         struct drm_device *dev = fb_helper->dev;
 439         bool do_delayed;
 440         int ret;
 441
 442         if (!drm_fbdev_emulation)
 443                 return -ENODEV;
 444
 445         drm_modeset_lock_all(dev);
 446         ret = restore_fbdev_mode(fb_helper);
 447
 448         do_delayed = fb_helper->delayed_hotplug;
 449         if (do_delayed)
 450                 fb_helper->delayed_hotplug = false;
 451         drm_modeset_unlock_all(dev);
 452
 453         if (do_delayed)
 454                 drm_fb_helper_hotplug_event(fb_helper);
 455         return ret;
 456 }
 457 EXPORT_SYMBOL(drm_fb_helper_restore_fbdev_mode_unlocked);
 458
 459 static bool drm_fb_helper_is_bound(struct drm_fb_helper *fb_helper)
 460 {
 461         struct drm_device *dev = fb_helper->dev;
 462         struct drm_crtc *crtc;
 463         int bound = 0, crtcs_bound = 0;
 464
 465         /* Sometimes user space wants everything disabled, so don't steal the
 466          * display if there's a master. */
 467         if (READ_ONCE(dev->master))
 468                 return false;
 469
 470         drm_for_each_crtc(crtc, dev) {
 471                 if (crtc->primary->fb)
 472                         crtcs_bound++;
 473                 if (crtc->primary->fb == fb_helper->fb)
 474                         bound++;
 475         }
 476
 477         if (bound < crtcs_bound)
 478                 return false;
 479
 480         return true;
 481 }
 482
 483 #ifdef CONFIG_MAGIC_SYSRQ
 484 /*
 485  * restore fbcon display for all kms driver's using this helper, used for sysrq
 486  * and panic handling.
 487  */
 488 static bool drm_fb_helper_force_kernel_mode(void)
 489 {
 490         bool ret, error = false;
 491         struct drm_fb_helper *helper;
 492
 493         if (list_empty(&kernel_fb_helper_list))
 494                 return false;
 495
 496         list_for_each_entry(helper, &kernel_fb_helper_list, kernel_fb_list) {
 497                 struct drm_device *dev = helper->dev;
 498
 499                 if (dev->switch_power_state == DRM_SWITCH_POWER_OFF)
 500                         continue;
 501
 502                 drm_modeset_lock_all(dev);
 503                 ret = restore_fbdev_mode(helper);
 504                 if (ret)
 505                         error = true;
 506                 drm_modeset_unlock_all(dev);
 507         }
 508         return error;
 509 }
 510
 511 static void drm_fb_helper_restore_work_fn(struct work_struct *ignored)
 512 {
 513         bool ret;
 514         ret = drm_fb_helper_force_kernel_mode();
 515         if (ret == true)
 516                 DRM_ERROR("Failed to restore crtc configuration\n");
 517 }
 518 static DECLARE_WORK(drm_fb_helper_restore_work, drm_fb_helper_restore_work_fn);
 519
 520 static void drm_fb_helper_sysrq(int dummy1)
 521 {
 522         schedule_work(&drm_fb_helper_restore_work);
 523 }
 524
 525 static struct sysrq_key_op sysrq_drm_fb_helper_restore_op = {
 526         .handler = drm_fb_helper_sysrq,
 527         .help_msg = "force-fb(V)",
 528         .action_msg = "Restore framebuffer console",
 529 };
 530 #else
 531 static struct sysrq_key_op sysrq_drm_fb_helper_restore_op = { };
 532 #endif
 533
 534 static void drm_fb_helper_dpms(struct fb_info *info, int dpms_mode)
 535 {
 536         struct drm_fb_helper *fb_helper = info->par;
 537         struct drm_device *dev = fb_helper->dev;
 538         struct drm_crtc *crtc;
 539         struct drm_connector *connector;
 540         int i, j;
 541
 542         /*
 543          * For each CRTC in this fb, turn the connectors on/off.
 544          */
 545         drm_modeset_lock_all(dev);
 546         if (!drm_fb_helper_is_bound(fb_helper)) {
 547                 drm_modeset_unlock_all(dev);
 548                 return;
 549         }
 550
 551         for (i = 0; i < fb_helper->crtc_count; i++) {
 552                 crtc = fb_helper->crtc_info[i].mode_set.crtc;
 553
 554                 if (!crtc->enabled)
 555                         continue;
 556
 557                 /* Walk the connectors & encoders on this fb turning them on/off */
 558                 for (j = 0; j < fb_helper->connector_count; j++) {
 559                         connector = fb_helper->connector_info[j]->connector;
 560                         connector->funcs->dpms(connector, dpms_mode);
 561                         drm_object_property_set_value(&connector->base,
 562                                 dev->mode_config.dpms_property, dpms_mode);
 563                 }
 564         }
 565         drm_modeset_unlock_all(dev);
 566 }
 567
 568 /**
 569  * drm_fb_helper_blank - implementation for ->fb_blank
 570  * @blank: desired blanking state
 571  * @info: fbdev registered by the helper
 572  */
 573 int drm_fb_helper_blank(int blank, struct fb_info *info)
 574 {
 575         if (oops_in_progress)
 576                 return -EBUSY;
 577
 578         switch (blank) {
 579         /* Display: On; HSync: On, VSync: On */
 580         case FB_BLANK_UNBLANK:
 581                 drm_fb_helper_dpms(info, DRM_MODE_DPMS_ON);
 582                 break;
 583         /* Display: Off; HSync: On, VSync: On */
 584         case FB_BLANK_NORMAL:
 585                 drm_fb_helper_dpms(info, DRM_MODE_DPMS_STANDBY);
 586                 break;
 587         /* Display: Off; HSync: Off, VSync: On */
 588         case FB_BLANK_HSYNC_SUSPEND:
 589                 drm_fb_helper_dpms(info, DRM_MODE_DPMS_STANDBY);
 590                 break;
 591         /* Display: Off; HSync: On, VSync: Off */
 592         case FB_BLANK_VSYNC_SUSPEND:
 593                 drm_fb_helper_dpms(info, DRM_MODE_DPMS_SUSPEND);
 594                 break;
 595         /* Display: Off; HSync: Off, VSync: Off */
 596         case FB_BLANK_POWERDOWN:
 597                 drm_fb_helper_dpms(info, DRM_MODE_DPMS_OFF);
 598                 break;
 599         }
 600         return 0;
 601 }
 602 EXPORT_SYMBOL(drm_fb_helper_blank);
 603
 604 static void drm_fb_helper_crtc_free(struct drm_fb_helper *helper)
 605 {
 606         int i;
 607
 608         for (i = 0; i < helper->connector_count; i++) {
 609                 drm_connector_unreference(helper->connector_info[i]->connector);
 610                 kfree(helper->connector_info[i]);
 611         }
 612         kfree(helper->connector_info);
 613         for (i = 0; i < helper->crtc_count; i++) {
 614                 kfree(helper->crtc_info[i].mode_set.connectors);
 615                 if (helper->crtc_info[i].mode_set.mode)
 616                         drm_mode_destroy(helper->dev, helper->crtc_info[i].mode_set.mode);
 617         }
 618         kfree(helper->crtc_info);
 619 }
 620
 621 static void drm_fb_helper_dirty_work(struct work_struct *work)
 622 {
 623         struct drm_fb_helper *helper = container_of(work, struct drm_fb_helper,
 624                                                     dirty_work);
 625         struct drm_clip_rect *clip = &helper->dirty_clip;
 626         struct drm_clip_rect clip_copy;
 627         unsigned long flags;
 628
 629         spin_lock_irqsave(&helper->dirty_lock, flags);
 630         clip_copy = *clip;
 631         clip->x1 = clip->y1 = ~0;
 632         clip->x2 = clip->y2 = 0;
 633         spin_unlock_irqrestore(&helper->dirty_lock, flags);
 634
 635         helper->fb->funcs->dirty(helper->fb, NULL, 0, 0, &clip_copy, 1);
 636 }
 637
 638 /**
 639  * drm_fb_helper_prepare - setup a drm_fb_helper structure
 640  * @dev: DRM device
 641  * @helper: driver-allocated fbdev helper structure to set up
 642  * @funcs: pointer to structure of functions associate with this helper
 643  *
 644  * Sets up the bare minimum to make the framebuffer helper usable. This is
 645  * useful to implement race-free initialization of the polling helpers.
 646  */
 647 void drm_fb_helper_prepare(struct drm_device *dev, struct drm_fb_helper *helper,
 648                            const struct drm_fb_helper_funcs *funcs)
 649 {
 650         INIT_LIST_HEAD(&helper->kernel_fb_list);
 651         spin_lock_init(&helper->dirty_lock);
 652         INIT_WORK(&helper->dirty_work, drm_fb_helper_dirty_work);
 653         helper->dirty_clip.x1 = helper->dirty_clip.y1 = ~0;
 654         helper->funcs = funcs;
 655         helper->dev = dev;
 656 }
 657 EXPORT_SYMBOL(drm_fb_helper_prepare);
 658
 659 /**
 660  * drm_fb_helper_init - initialize a drm_fb_helper structure
 661  * @dev: drm device
 662  * @fb_helper: driver-allocated fbdev helper structure to initialize
 663  * @crtc_count: maximum number of crtcs to support in this fbdev emulation
 664  * @max_conn_count: max connector count
 665  *
 666  * This allocates the structures for the fbdev helper with the given limits.
 667  * Note that this won't yet touch the hardware (through the driver interfaces)
 668  * nor register the fbdev. This is only done in drm_fb_helper_initial_config()
 669  * to allow driver writes more control over the exact init sequence.
 670  *
 671  * Drivers must call drm_fb_helper_prepare() before calling this function.
 672  *
 673  * RETURNS:
 674  * Zero if everything went ok, nonzero otherwise.
 675  */
 676 int drm_fb_helper_init(struct drm_device *dev,
 677                        struct drm_fb_helper *fb_helper,
 678                        int crtc_count, int max_conn_count)
 679 {
 680         struct drm_crtc *crtc;
 681         int i;
 682
 683         if (!drm_fbdev_emulation)
 684                 return 0;
 685
 686         if (!max_conn_count)
 687                 return -EINVAL;
 688
 689         fb_helper->crtc_info = kcalloc(crtc_count, sizeof(struct drm_fb_helper_crtc), GFP_KERNEL);
 690         if (!fb_helper->crtc_info)
 691                 return -ENOMEM;
 692
 693         fb_helper->crtc_count = crtc_count;
 694         fb_helper->connector_info = kcalloc(dev->mode_config.num_connector, sizeof(struct drm_fb_helper_connector *), GFP_KERNEL);
 695         if (!fb_helper->connector_info) {
 696                 kfree(fb_helper->crtc_info);
 697                 return -ENOMEM;
 698         }
 699         fb_helper->connector_info_alloc_count = dev->mode_config.num_connector;
 700         fb_helper->connector_count = 0;
 701
 702         for (i = 0; i < crtc_count; i++) {
 703                 fb_helper->crtc_info[i].mode_set.connectors =
 704                         kcalloc(max_conn_count,
 705                                 sizeof(struct drm_connector *),
 706                                 GFP_KERNEL);
 707
 708                 if (!fb_helper->crtc_info[i].mode_set.connectors)
 709                         goto out_free;
 710                 fb_helper->crtc_info[i].mode_set.num_connectors = 0;
 711         }
 712
 713         i = 0;
 714         drm_for_each_crtc(crtc, dev) {
 715                 fb_helper->crtc_info[i].mode_set.crtc = crtc;
 716                 i++;
 717         }
 718
 719         return 0;
 720 out_free:
 721         drm_fb_helper_crtc_free(fb_helper);
 722         return -ENOMEM;
 723 }
 724 EXPORT_SYMBOL(drm_fb_helper_init);
 725
 726 /**
 727  * drm_fb_helper_alloc_fbi - allocate fb_info and some of its members
 728  * @fb_helper: driver-allocated fbdev helper
 729  *
 730  * A helper to alloc fb_info and the members cmap and apertures. Called
 731  * by the driver within the fb_probe fb_helper callback function.
 732  *
 733  * RETURNS:
 734  * fb_info pointer if things went okay, pointer containing error code
 735  * otherwise
 736  */
 737 struct fb_info *drm_fb_helper_alloc_fbi(struct drm_fb_helper *fb_helper)
 738 {
 739         struct device *dev = fb_helper->dev->dev;
 740         struct fb_info *info;
 741         int ret;
 742
 743         info = framebuffer_alloc(0, dev);
 744         if (!info)
 745                 return ERR_PTR(-ENOMEM);
 746
 747         ret = fb_alloc_cmap(&info->cmap, 256, 0);
 748         if (ret)
 749                 goto err_release;
 750
 751         info->apertures = alloc_apertures(1);
 752         if (!info->apertures) {
 753                 ret = -ENOMEM;
 754                 goto err_free_cmap;
 755         }
 756
 757         fb_helper->fbdev = info;
 758
 759         return info;
 760
 761 err_free_cmap:
 762         fb_dealloc_cmap(&info->cmap);
 763 err_release:
 764         framebuffer_release(info);
 765         return ERR_PTR(ret);
 766 }
 767 EXPORT_SYMBOL(drm_fb_helper_alloc_fbi);
 768
 769 /**
 770  * drm_fb_helper_unregister_fbi - unregister fb_info framebuffer device
 771  * @fb_helper: driver-allocated fbdev helper
 772  *
 773  * A wrapper around unregister_framebuffer, to release the fb_info
 774  * framebuffer device
 775  */
 776 void drm_fb_helper_unregister_fbi(struct drm_fb_helper *fb_helper)
 777 {
 778         if (fb_helper && fb_helper->fbdev)
 779                 unregister_framebuffer(fb_helper->fbdev);
 780 }
 781 EXPORT_SYMBOL(drm_fb_helper_unregister_fbi);
 782
 783 /**
 784  * drm_fb_helper_release_fbi - dealloc fb_info and its members
 785  * @fb_helper: driver-allocated fbdev helper
 786  *
 787  * A helper to free memory taken by fb_info and the members cmap and
 788  * apertures
 789  */
 790 void drm_fb_helper_release_fbi(struct drm_fb_helper *fb_helper)
 791 {
 792         if (fb_helper) {
 793                 struct fb_info *info = fb_helper->fbdev;
 794
 795                 if (info) {
 796                         if (info->cmap.len)
 797                                 fb_dealloc_cmap(&info->cmap);
 798                         framebuffer_release(info);
 799                 }
 800
 801                 fb_helper->fbdev = NULL;
 802         }
 803 }
 804 EXPORT_SYMBOL(drm_fb_helper_release_fbi);
 805
 806 void drm_fb_helper_fini(struct drm_fb_helper *fb_helper)
 807 {
 808         if (!drm_fbdev_emulation)
 809                 return;
 810
 811         if (!list_empty(&fb_helper->kernel_fb_list)) {
 812                 list_del(&fb_helper->kernel_fb_list);
 813                 if (list_empty(&kernel_fb_helper_list)) {
 814                         unregister_sysrq_key('v', &sysrq_drm_fb_helper_restore_op);
 815                 }
 816         }
 817
 818         drm_fb_helper_crtc_free(fb_helper);
 819
 820 }
 821 EXPORT_SYMBOL(drm_fb_helper_fini);
 822
 823 /**
 824  * drm_fb_helper_unlink_fbi - wrapper around unlink_framebuffer
 825  * @fb_helper: driver-allocated fbdev helper
 826  *
 827  * A wrapper around unlink_framebuffer implemented by fbdev core
 828  */
 829 void drm_fb_helper_unlink_fbi(struct drm_fb_helper *fb_helper)
 830 {
 831         if (fb_helper && fb_helper->fbdev)
 832                 unlink_framebuffer(fb_helper->fbdev);
 833 }
 834 EXPORT_SYMBOL(drm_fb_helper_unlink_fbi);
 835
 836 static void drm_fb_helper_dirty(struct fb_info *info, u32 x, u32 y,
 837                                 u32 width, u32 height)
 838 {
 839         struct drm_fb_helper *helper = info->par;
 840         struct drm_clip_rect *clip = &helper->dirty_clip;
 841         unsigned long flags;
 842
 843         if (!helper->fb->funcs->dirty)
 844                 return;
 845
 846         spin_lock_irqsave(&helper->dirty_lock, flags);
 847         clip->x1 = min_t(u32, clip->x1, x);
 848         clip->y1 = min_t(u32, clip->y1, y);
 849         clip->x2 = max_t(u32, clip->x2, x + width);
 850         clip->y2 = max_t(u32, clip->y2, y + height);
 851         spin_unlock_irqrestore(&helper->dirty_lock, flags);
 852
 853         schedule_work(&helper->dirty_work);
 854 }
 855
 856 /**
 857  * drm_fb_helper_deferred_io() - fbdev deferred_io callback function
 858  * @info: fb_info struct pointer
 859  * @pagelist: list of dirty mmap framebuffer pages
 860  *
 861  * This function is used as the &fb_deferred_io ->deferred_io
 862  * callback function for flushing the fbdev mmap writes.
 863  */
 864 void drm_fb_helper_deferred_io(struct fb_info *info,
 865                                struct list_head *pagelist)
 866 {
 867         unsigned long start, end, min, max;
 868         struct page *page;
 869         u32 y1, y2;
 870
 871         min = ULONG_MAX;
 872         max = 0;
 873         list_for_each_entry(page, pagelist, lru) {
 874                 start = page->index << PAGE_SHIFT;
 875                 end = start + PAGE_SIZE - 1;
 876                 min = min(min, start);
 877                 max = max(max, end);
 878         }
 879
 880         if (min < max) {
 881                 y1 = min / info->fix.line_length;
 882                 y2 = min_t(u32, DIV_ROUND_UP(max, info->fix.line_length),
 883                            info->var.yres);
 884                 drm_fb_helper_dirty(info, 0, y1, info->var.xres, y2 - y1);
 885         }
 886 }
 887 EXPORT_SYMBOL(drm_fb_helper_deferred_io);
 888
 889 /**
 890  * drm_fb_helper_sys_read - wrapper around fb_sys_read
 891  * @info: fb_info struct pointer
 892  * @buf: userspace buffer to read from framebuffer memory
 893  * @count: number of bytes to read from framebuffer memory
 894  * @ppos: read offset within framebuffer memory
 895  *
 896  * A wrapper around fb_sys_read implemented by fbdev core
 897  */
 898 ssize_t drm_fb_helper_sys_read(struct fb_info *info, char __user *buf,
 899                                size_t count, loff_t *ppos)
 900 {
 901         return fb_sys_read(info, buf, count, ppos);
 902 }
 903 EXPORT_SYMBOL(drm_fb_helper_sys_read);
 904
 905 /**
 906  * drm_fb_helper_sys_write - wrapper around fb_sys_write
 907  * @info: fb_info struct pointer
 908  * @buf: userspace buffer to write to framebuffer memory
 909  * @count: number of bytes to write to framebuffer memory
 910  * @ppos: write offset within framebuffer memory
 911  *
 912  * A wrapper around fb_sys_write implemented by fbdev core
 913  */
 914 ssize_t drm_fb_helper_sys_write(struct fb_info *info, const char __user *buf,
 915                                 size_t count, loff_t *ppos)
 916 {
 917         ssize_t ret;
 918
 919         ret = fb_sys_write(info, buf, count, ppos);
 920         if (ret > 0)
 921                 drm_fb_helper_dirty(info, 0, 0, info->var.xres,
 922                                     info->var.yres);
 923
 924         return ret;
 925 }
 926 EXPORT_SYMBOL(drm_fb_helper_sys_write);
 927
 928 /**
 929  * drm_fb_helper_sys_fillrect - wrapper around sys_fillrect
 930  * @info: fbdev registered by the helper
 931  * @rect: info about rectangle to fill
 932  *
 933  * A wrapper around sys_fillrect implemented by fbdev core
 934  */
 935 void drm_fb_helper_sys_fillrect(struct fb_info *info,
 936                                 const struct fb_fillrect *rect)
 937 {
 938         sys_fillrect(info, rect);
 939         drm_fb_helper_dirty(info, rect->dx, rect->dy,
 940                             rect->width, rect->height);
 941 }
 942 EXPORT_SYMBOL(drm_fb_helper_sys_fillrect);
 943
 944 /**
 945  * drm_fb_helper_sys_copyarea - wrapper around sys_copyarea
 946  * @info: fbdev registered by the helper
 947  * @area: info about area to copy
 948  *
 949  * A wrapper around sys_copyarea implemented by fbdev core
 950  */
 951 void drm_fb_helper_sys_copyarea(struct fb_info *info,
 952                                 const struct fb_copyarea *area)
 953 {
 954         sys_copyarea(info, area);
 955         drm_fb_helper_dirty(info, area->dx, area->dy,
 956                             area->width, area->height);
 957 }
 958 EXPORT_SYMBOL(drm_fb_helper_sys_copyarea);
 959
 960 /**
 961  * drm_fb_helper_sys_imageblit - wrapper around sys_imageblit
 962  * @info: fbdev registered by the helper
 963  * @image: info about image to blit
 964  *
 965  * A wrapper around sys_imageblit implemented by fbdev core
 966  */
 967 void drm_fb_helper_sys_imageblit(struct fb_info *info,
 968                                  const struct fb_image *image)
 969 {
 970         sys_imageblit(info, image);
 971         drm_fb_helper_dirty(info, image->dx, image->dy,
 972                             image->width, image->height);
 973 }
 974 EXPORT_SYMBOL(drm_fb_helper_sys_imageblit);
 975
 976 /**
 977  * drm_fb_helper_cfb_fillrect - wrapper around cfb_fillrect
 978  * @info: fbdev registered by the helper
 979  * @rect: info about rectangle to fill
 980  *
 981  * A wrapper around cfb_imageblit implemented by fbdev core
 982  */
 983 void drm_fb_helper_cfb_fillrect(struct fb_info *info,
 984                                 const struct fb_fillrect *rect)
 985 {
 986         cfb_fillrect(info, rect);
 987         drm_fb_helper_dirty(info, rect->dx, rect->dy,
 988                             rect->width, rect->height);
 989 }
 990 EXPORT_SYMBOL(drm_fb_helper_cfb_fillrect);
 991
 992 /**
 993  * drm_fb_helper_cfb_copyarea - wrapper around cfb_copyarea
 994  * @info: fbdev registered by the helper
 995  * @area: info about area to copy
 996  *
 997  * A wrapper around cfb_copyarea implemented by fbdev core
 998  */
 999 void drm_fb_helper_cfb_copyarea(struct fb_info *info,
1000                                 const struct fb_copyarea *area)
1001 {
1002         cfb_copyarea(info, area);
1003         drm_fb_helper_dirty(info, area->dx, area->dy,
1004                             area->width, area->height);
1005 }
1006 EXPORT_SYMBOL(drm_fb_helper_cfb_copyarea);
1007
1008 /**
1009  * drm_fb_helper_cfb_imageblit - wrapper around cfb_imageblit
1010  * @info: fbdev registered by the helper
1011  * @image: info about image to blit
1012  *
1013  * A wrapper around cfb_imageblit implemented by fbdev core
1014  */
1015 void drm_fb_helper_cfb_imageblit(struct fb_info *info,
1016                                  const struct fb_image *image)
1017 {
1018         cfb_imageblit(info, image);
1019         drm_fb_helper_dirty(info, image->dx, image->dy,
1020                             image->width, image->height);
1021 }
1022 EXPORT_SYMBOL(drm_fb_helper_cfb_imageblit);
1023
1024 /**
1025  * drm_fb_helper_set_suspend - wrapper around fb_set_suspend
1026  * @fb_helper: driver-allocated fbdev helper
1027  * @state: desired state, zero to resume, non-zero to suspend
1028  *
1029  * A wrapper around fb_set_suspend implemented by fbdev core
1030  */
1031 void drm_fb_helper_set_suspend(struct drm_fb_helper *fb_helper, int state)
1032 {
1033         if (fb_helper && fb_helper->fbdev)
1034                 fb_set_suspend(fb_helper->fbdev, state);
1035 }
1036 EXPORT_SYMBOL(drm_fb_helper_set_suspend);
1037
1038 static int setcolreg(struct drm_crtc *crtc, u16 red, u16 green,
1039                      u16 blue, u16 regno, struct fb_info *info)
1040 {
1041         struct drm_fb_helper *fb_helper = info->par;
1042         struct drm_framebuffer *fb = fb_helper->fb;
1043
1044         if (info->fix.visual == FB_VISUAL_TRUECOLOR) {
1045                 u32 *palette;
1046                 u32 value;
1047                 /* place color in psuedopalette */
1048                 if (regno > 16)
1049                         return -EINVAL;
1050                 palette = (u32 *)info->pseudo_palette;
1051                 red >>= (16 - info->var.red.length);
1052                 green >>= (16 - info->var.green.length);
1053                 blue >>= (16 - info->var.blue.length);
1054                 value = (red << info->var.red.offset) |
1055                         (green << info->var.green.offset) |
1056                         (blue << info->var.blue.offset);
1057                 if (info->var.transp.length > 0) {
1058                         u32 mask = (1 << info->var.transp.length) - 1;
1059                         mask <<= info->var.transp.offset;
1060                         value |= mask;
1061                 }
1062                 palette[regno] = value;
1063                 return 0;
1064         }
1065
1066         /*
1067          * The driver really shouldn't advertise pseudo/directcolor
1068          * visuals if it can't deal with the palette.
1069          */
1070         if (WARN_ON(!fb_helper->funcs->gamma_set ||
1071                     !fb_helper->funcs->gamma_get))
1072                 return -EINVAL;
1073
1074         WARN_ON(fb->bits_per_pixel != 8);
1075
1076         fb_helper->funcs->gamma_set(crtc, red, green, blue, regno);
1077
1078         return 0;
1079 }
1080
1081 /**
1082  * drm_fb_helper_setcmap - implementation for ->fb_setcmap
1083  * @cmap: cmap to set
1084  * @info: fbdev registered by the helper
1085  */
1086 int drm_fb_helper_setcmap(struct fb_cmap *cmap, struct fb_info *info)
1087 {
1088         struct drm_fb_helper *fb_helper = info->par;
1089         struct drm_device *dev = fb_helper->dev;
1090         const struct drm_crtc_helper_funcs *crtc_funcs;
1091         u16 *red, *green, *blue, *transp;
1092         struct drm_crtc *crtc;
1093         int i, j, rc = 0;
1094         int start;
1095
1096         if (oops_in_progress)
1097                 return -EBUSY;
1098
1099         drm_modeset_lock_all(dev);
1100         if (!drm_fb_helper_is_bound(fb_helper)) {
1101                 drm_modeset_unlock_all(dev);
1102                 return -EBUSY;
1103         }
1104
1105         for (i = 0; i < fb_helper->crtc_count; i++) {
1106                 crtc = fb_helper->crtc_info[i].mode_set.crtc;
1107                 crtc_funcs = crtc->helper_private;
1108
1109                 red = cmap->red;
1110                 green = cmap->green;
1111                 blue = cmap->blue;
1112                 transp = cmap->transp;
1113                 start = cmap->start;
1114
1115                 for (j = 0; j < cmap->len; j++) {
1116                         u16 hred, hgreen, hblue, htransp = 0xffff;
1117
1118                         hred = *red++;
1119                         hgreen = *green++;
1120                         hblue = *blue++;
1121
1122                         if (transp)
1123                                 htransp = *transp++;
1124
1125                         rc = setcolreg(crtc, hred, hgreen, hblue, start++, info);
1126                         if (rc)
1127                                 goto out;
1128                 }
1129                 if (crtc_funcs->load_lut)
1130                         crtc_funcs->load_lut(crtc);
1131         }
1132  out:
1133         drm_modeset_unlock_all(dev);
1134         return rc;
1135 }
1136 EXPORT_SYMBOL(drm_fb_helper_setcmap);
1137
1138 /**
1139  * drm_fb_helper_check_var - implementation for ->fb_check_var
1140  * @var: screeninfo to check
1141  * @info: fbdev registered by the helper
1142  */
1143 int drm_fb_helper_check_var(struct fb_var_screeninfo *var,
1144                             struct fb_info *info)
1145 {
1146         struct drm_fb_helper *fb_helper = info->par;
1147         struct drm_framebuffer *fb = fb_helper->fb;
1148         int depth;
1149
1150         if (var->pixclock != 0 || in_dbg_master())
1151                 return -EINVAL;
1152
1153         /* Need to resize the fb object !!! */
1154         if (var->bits_per_pixel > fb->bits_per_pixel ||
1155             var->xres > fb->width || var->yres > fb->height ||
1156             var->xres_virtual > fb->width || var->yres_virtual > fb->height) {
1157                 DRM_DEBUG("fb userspace requested width/height/bpp is greater than current fb "
1158                           "request %dx%d-%d (virtual %dx%d) > %dx%d-%d\n",
1159                           var->xres, var->yres, var->bits_per_pixel,
1160                           var->xres_virtual, var->yres_virtual,
1161                           fb->width, fb->height, fb->bits_per_pixel);
1162                 return -EINVAL;
1163         }
1164
1165         switch (var->bits_per_pixel) {
1166         case 16:
1167                 depth = (var->green.length == 6) ? 16 : 15;
1168                 break;
1169         case 32:
1170                 depth = (var->transp.length > 0) ? 32 : 24;
1171                 break;
1172         default:
1173                 depth = var->bits_per_pixel;
1174                 break;
1175         }
1176
1177         switch (depth) {
1178         case 8:
1179                 var->red.offset = 0;
1180                 var->green.offset = 0;
1181                 var->blue.offset = 0;
1182                 var->red.length = 8;
1183                 var->green.length = 8;
1184                 var->blue.length = 8;
1185                 var->transp.length = 0;
1186                 var->transp.offset = 0;
1187                 break;
1188         case 15:
1189                 var->red.offset = 10;
1190                 var->green.offset = 5;
1191                 var->blue.offset = 0;
1192                 var->red.length = 5;
1193                 var->green.length = 5;
1194                 var->blue.length = 5;
1195                 var->transp.length = 1;
1196                 var->transp.offset = 15;
1197                 break;
1198         case 16:
1199                 var->red.offset = 11;
1200                 var->green.offset = 5;
1201                 var->blue.offset = 0;
1202                 var->red.length = 5;
1203                 var->green.length = 6;
1204                 var->blue.length = 5;
1205                 var->transp.length = 0;
1206                 var->transp.offset = 0;
1207                 break;
1208         case 24:
1209                 var->red.offset = 16;
1210                 var->green.offset = 8;
1211                 var->blue.offset = 0;
1212                 var->red.length = 8;
1213                 var->green.length = 8;
1214                 var->blue.length = 8;
1215                 var->transp.length = 0;
1216                 var->transp.offset = 0;
1217                 break;
1218         case 32:
1219                 var->red.offset = 16;
1220                 var->green.offset = 8;
1221                 var->blue.offset = 0;
1222                 var->red.length = 8;
1223                 var->green.length = 8;
1224                 var->blue.length = 8;
1225                 var->transp.length = 8;
1226                 var->transp.offset = 24;
1227                 break;
1228         default:
1229                 return -EINVAL;
1230         }
1231         return 0;
1232 }
1233 EXPORT_SYMBOL(drm_fb_helper_check_var);
1234
1235 /**
1236  * drm_fb_helper_set_par - implementation for ->fb_set_par
1237  * @info: fbdev registered by the helper
1238  *
1239  * This will let fbcon do the mode init and is called at initialization time by
1240  * the fbdev core when registering the driver, and later on through the hotplug
1241  * callback.
1242  */
1243 int drm_fb_helper_set_par(struct fb_info *info)
1244 {
1245         struct drm_fb_helper *fb_helper = info->par;
1246         struct fb_var_screeninfo *var = &info->var;
1247
1248         if (oops_in_progress)
1249                 return -EBUSY;
1250
1251         if (var->pixclock != 0) {
1252                 DRM_ERROR("PIXEL CLOCK SET\n");
1253                 return -EINVAL;
1254         }
1255
1256         drm_fb_helper_restore_fbdev_mode_unlocked(fb_helper);
1257
1258         return 0;
1259 }
1260 EXPORT_SYMBOL(drm_fb_helper_set_par);
1261
1262 static int pan_display_atomic(struct fb_var_screeninfo *var,
1263                               struct fb_info *info)
1264 {
1265         struct drm_fb_helper *fb_helper = info->par;
1266         struct drm_device *dev = fb_helper->dev;
1267         struct drm_atomic_state *state;
1268         struct drm_plane *plane;
1269         int i, ret;
1270         unsigned plane_mask;
1271
1272         state = drm_atomic_state_alloc(dev);
1273         if (!state)
1274                 return -ENOMEM;
1275
1276         state->acquire_ctx = dev->mode_config.acquire_ctx;
1277 retry:
1278         plane_mask = 0;
1279         for(i = 0; i < fb_helper->crtc_count; i++) {
1280                 struct drm_mode_set *mode_set;
1281
1282                 mode_set = &fb_helper->crtc_info[i].mode_set;
1283
1284                 mode_set->x = var->xoffset;
1285                 mode_set->y = var->yoffset;
1286
1287                 ret = __drm_atomic_helper_set_config(mode_set, state);
1288                 if (ret != 0)
1289                         goto fail;
1290
1291                 plane = mode_set->crtc->primary;
1292                 plane_mask |= (1 << drm_plane_index(plane));
1293                 plane->old_fb = plane->fb;
1294         }
1295
1296         ret = drm_atomic_commit(state);
1297         if (ret != 0)
1298                 goto fail;
1299
1300         info->var.xoffset = var->xoffset;
1301         info->var.yoffset = var->yoffset;
1302
1303
1304 fail:
1305         drm_atomic_clean_old_fb(dev, plane_mask, ret);
1306
1307         if (ret == -EDEADLK)
1308                 goto backoff;
1309
1310         if (ret != 0)
1311                 drm_atomic_state_free(state);
1312
1313         return ret;
1314
1315 backoff:
1316         drm_atomic_state_clear(state);
1317         drm_atomic_legacy_backoff(state);
1318
1319         goto retry;
1320 }
1321
1322 /**
1323  * drm_fb_helper_pan_display - implementation for ->fb_pan_display
1324  * @var: updated screen information
1325  * @info: fbdev registered by the helper
1326  */
1327 int drm_fb_helper_pan_display(struct fb_var_screeninfo *var,
1328                               struct fb_info *info)
1329 {
1330         struct drm_fb_helper *fb_helper = info->par;
1331         struct drm_device *dev = fb_helper->dev;
1332         struct drm_mode_set *modeset;
1333         int ret = 0;
1334         int i;
1335
1336         if (oops_in_progress)
1337                 return -EBUSY;
1338
1339         drm_modeset_lock_all(dev);
1340         if (!drm_fb_helper_is_bound(fb_helper)) {
1341                 drm_modeset_unlock_all(dev);
1342                 return -EBUSY;
1343         }
1344
1345         if (dev->mode_config.funcs->atomic_commit) {
1346                 ret = pan_display_atomic(var, info);
1347                 goto unlock;
1348         }
1349
1350         for (i = 0; i < fb_helper->crtc_count; i++) {
1351                 modeset = &fb_helper->crtc_info[i].mode_set;
1352
1353                 modeset->x = var->xoffset;
1354                 modeset->y = var->yoffset;
1355
1356                 if (modeset->num_connectors) {
1357                         ret = drm_mode_set_config_internal(modeset);
1358                         if (!ret) {
1359                                 info->var.xoffset = var->xoffset;
1360                                 info->var.yoffset = var->yoffset;
1361                         }
1362                 }
1363         }
1364 unlock:
1365         drm_modeset_unlock_all(dev);
1366         return ret;
1367 }
1368 EXPORT_SYMBOL(drm_fb_helper_pan_display);
1369
1370 /*
1371  * Allocates the backing storage and sets up the fbdev info structure through
1372  * the ->fb_probe callback and then registers the fbdev and sets up the panic
1373  * notifier.
1374  */
1375 static int drm_fb_helper_single_fb_probe(struct drm_fb_helper *fb_helper,
1376                                          int preferred_bpp)
1377 {
1378         int ret = 0;
1379         int crtc_count = 0;
1380         int i;
1381         struct fb_info *info;
1382         struct drm_fb_helper_surface_size sizes;
1383         int gamma_size = 0;
1384
1385         memset(&sizes, 0, sizeof(struct drm_fb_helper_surface_size));
1386         sizes.surface_depth = 24;
1387         sizes.surface_bpp = 32;
1388         sizes.fb_width = (unsigned)-1;
1389         sizes.fb_height = (unsigned)-1;
1390
1391         /* if driver picks 8 or 16 by default use that
1392            for both depth/bpp */
1393         if (preferred_bpp != sizes.surface_bpp)
1394                 sizes.surface_depth = sizes.surface_bpp = preferred_bpp;
1395
1396         /* first up get a count of crtcs now in use and new min/maxes width/heights */
1397         for (i = 0; i < fb_helper->connector_count; i++) {
1398                 struct drm_fb_helper_connector *fb_helper_conn = fb_helper->connector_info[i];
1399                 struct drm_cmdline_mode *cmdline_mode;
1400
1401                 cmdline_mode = &fb_helper_conn->connector->cmdline_mode;
1402
1403                 if (cmdline_mode->bpp_specified) {
1404                         switch (cmdline_mode->bpp) {
1405                         case 8:
1406                                 sizes.surface_depth = sizes.surface_bpp = 8;
1407                                 break;
1408                         case 15:
1409                                 sizes.surface_depth = 15;
1410                                 sizes.surface_bpp = 16;
1411                                 break;
1412                         case 16:
1413                                 sizes.surface_depth = sizes.surface_bpp = 16;
1414                                 break;
1415                         case 24:
1416                                 sizes.surface_depth = sizes.surface_bpp = 24;
1417                                 break;
1418                         case 32:
1419                                 sizes.surface_depth = 24;
1420                                 sizes.surface_bpp = 32;
1421                                 break;
1422                         }
1423                         break;
1424                 }
1425         }
1426
1427         crtc_count = 0;
1428         for (i = 0; i < fb_helper->crtc_count; i++) {
1429                 struct drm_display_mode *desired_mode;
1430                 struct drm_mode_set *mode_set;
1431                 int x, y, j;
1432                 /* in case of tile group, are we the last tile vert or horiz?
1433                  * If no tile group you are always the last one both vertically
1434                  * and horizontally
1435                  */
1436                 bool lastv = true, lasth = true;
1437
1438                 desired_mode = fb_helper->crtc_info[i].desired_mode;
1439                 mode_set = &fb_helper->crtc_info[i].mode_set;
1440
1441                 if (!desired_mode)
1442                         continue;
1443
1444                 crtc_count++;
1445
1446                 x = fb_helper->crtc_info[i].x;
1447                 y = fb_helper->crtc_info[i].y;
1448
1449                 if (gamma_size == 0)
1450                         gamma_size = fb_helper->crtc_info[i].mode_set.crtc->gamma_size;
1451
1452                 sizes.surface_width  = max_t(u32, desired_mode->hdisplay + x, sizes.surface_width);
1453                 sizes.surface_height = max_t(u32, desired_mode->vdisplay + y, sizes.surface_height);
1454
1455                 for (j = 0; j < mode_set->num_connectors; j++) {
1456                         struct drm_connector *connector = mode_set->connectors[j];
1457                         if (connector->has_tile) {
1458                                 lasth = (connector->tile_h_loc == (connector->num_h_tile - 1));
1459                                 lastv = (connector->tile_v_loc == (connector->num_v_tile - 1));
1460                                 /* cloning to multiple tiles is just crazy-talk, so: */
1461                                 break;
1462                         }
1463                 }
1464
1465                 if (lasth)
1466                         sizes.fb_width  = min_t(u32, desired_mode->hdisplay + x, sizes.fb_width);
1467                 if (lastv)
1468                         sizes.fb_height = min_t(u32, desired_mode->vdisplay + y, sizes.fb_height);
1469         }
1470
1471         if (crtc_count == 0 || sizes.fb_width == -1 || sizes.fb_height == -1) {
1472                 /* hmm everyone went away - assume VGA cable just fell out
1473                    and will come back later. */
1474                 DRM_INFO("Cannot find any crtc or sizes - going 1024x768\n");
1475                 sizes.fb_width = sizes.surface_width = 1024;
1476                 sizes.fb_height = sizes.surface_height = 768;
1477         }
1478
1479         /* push down into drivers */
1480         ret = (*fb_helper->funcs->fb_probe)(fb_helper, &sizes);
1481         if (ret < 0)
1482                 return ret;
1483
1484         info = fb_helper->fbdev;
1485
1486         /*
1487          * Set the fb pointer - usually drm_setup_crtcs does this for hotplug
1488          * events, but at init time drm_setup_crtcs needs to be called before
1489          * the fb is allocated (since we need to figure out the desired size of
1490          * the fb before we can allocate it ...). Hence we need to fix things up
1491          * here again.
1492          */
1493         for (i = 0; i < fb_helper->crtc_count; i++)
1494                 if (fb_helper->crtc_info[i].mode_set.num_connectors)
1495                         fb_helper->crtc_info[i].mode_set.fb = fb_helper->fb;
1496
1497
1498         info->var.pixclock = 0;
1499         if (register_framebuffer(info) < 0)
1500                 return -EINVAL;
1501
1502         dev_info(fb_helper->dev->dev, "fb%d: %s frame buffer device\n",
1503                         info->node, info->fix.id);
1504
1505         if (list_empty(&kernel_fb_helper_list)) {
1506                 register_sysrq_key('v', &sysrq_drm_fb_helper_restore_op);
1507         }
1508
1509         list_add(&fb_helper->kernel_fb_list, &kernel_fb_helper_list);
1510
1511         return 0;
1512 }
1513
1514 /**
1515  * drm_fb_helper_fill_fix - initializes fixed fbdev information
1516  * @info: fbdev registered by the helper
1517  * @pitch: desired pitch
1518  * @depth: desired depth
1519  *
1520  * Helper to fill in the fixed fbdev information useful for a non-accelerated
1521  * fbdev emulations. Drivers which support acceleration methods which impose
1522  * additional constraints need to set up their own limits.
1523  *
1524  * Drivers should call this (or their equivalent setup code) from their
1525  * ->fb_probe callback.
1526  */
1527 void drm_fb_helper_fill_fix(struct fb_info *info, uint32_t pitch,
1528                             uint32_t depth)
1529 {
1530         info->fix.type = FB_TYPE_PACKED_PIXELS;
1531         info->fix.visual = depth == 8 ? FB_VISUAL_PSEUDOCOLOR :
1532                 FB_VISUAL_TRUECOLOR;
1533         info->fix.mmio_start = 0;
1534         info->fix.mmio_len = 0;
1535         info->fix.type_aux = 0;
1536         info->fix.xpanstep = 1; /* doing it in hw */
1537         info->fix.ypanstep = 1; /* doing it in hw */
1538         info->fix.ywrapstep = 0;
1539         info->fix.accel = FB_ACCEL_NONE;
1540
1541         info->fix.line_length = pitch;
1542         return;
1543 }
1544 EXPORT_SYMBOL(drm_fb_helper_fill_fix);
1545
1546 /**
1547  * drm_fb_helper_fill_var - initalizes variable fbdev information
1548  * @info: fbdev instance to set up
1549  * @fb_helper: fb helper instance to use as template
1550  * @fb_width: desired fb width
1551  * @fb_height: desired fb height
1552  *
1553  * Sets up the variable fbdev metainformation from the given fb helper instance
1554  * and the drm framebuffer allocated in fb_helper->fb.
1555  *
1556  * Drivers should call this (or their equivalent setup code) from their
1557  * ->fb_probe callback after having allocated the fbdev backing
1558  * storage framebuffer.
1559  */
1560 void drm_fb_helper_fill_var(struct fb_info *info, struct drm_fb_helper *fb_helper,
1561                             uint32_t fb_width, uint32_t fb_height)
1562 {
1563         struct drm_framebuffer *fb = fb_helper->fb;
1564         info->pseudo_palette = fb_helper->pseudo_palette;
1565         info->var.xres_virtual = fb->width;
1566         info->var.yres_virtual = fb->height;
1567         info->var.bits_per_pixel = fb->bits_per_pixel;
1568         info->var.accel_flags = FB_ACCELF_TEXT;
1569         info->var.xoffset = 0;
1570         info->var.yoffset = 0;
1571         info->var.activate = FB_ACTIVATE_NOW;
1572         info->var.height = -1;
1573         info->var.width = -1;
1574
1575         switch (fb->depth) {
1576         case 8:
1577                 info->var.red.offset = 0;
1578                 info->var.green.offset = 0;
1579                 info->var.blue.offset = 0;
1580                 info->var.red.length = 8; /* 8bit DAC */
1581                 info->var.green.length = 8;
1582                 info->var.blue.length = 8;
1583                 info->var.transp.offset = 0;
1584                 info->var.transp.length = 0;
1585                 break;
1586         case 15:
1587                 info->var.red.offset = 10;
1588                 info->var.green.offset = 5;
1589                 info->var.blue.offset = 0;
1590                 info->var.red.length = 5;
1591                 info->var.green.length = 5;
1592                 info->var.blue.length = 5;
1593                 info->var.transp.offset = 15;
1594                 info->var.transp.length = 1;
1595                 break;
1596         case 16:
1597                 info->var.red.offset = 11;
1598                 info->var.green.offset = 5;
1599                 info->var.blue.offset = 0;
1600                 info->var.red.length = 5;
1601                 info->var.green.length = 6;
1602                 info->var.blue.length = 5;
1603                 info->var.transp.offset = 0;
1604                 break;
1605         case 24:
1606                 info->var.red.offset = 16;
1607                 info->var.green.offset = 8;
1608                 info->var.blue.offset = 0;
1609                 info->var.red.length = 8;
1610                 info->var.green.length = 8;
1611                 info->var.blue.length = 8;
1612                 info->var.transp.offset = 0;
1613                 info->var.transp.length = 0;
1614                 break;
1615         case 32:
1616                 info->var.red.offset = 16;
1617                 info->var.green.offset = 8;
1618                 info->var.blue.offset = 0;
1619                 info->var.red.length = 8;
1620                 info->var.green.length = 8;
1621                 info->var.blue.length = 8;
1622                 info->var.transp.offset = 24;
1623                 info->var.transp.length = 8;
1624                 break;
1625         default:
1626                 break;
1627         }
1628
1629         info->var.xres = fb_width;
1630         info->var.yres = fb_height;
1631 }
1632 EXPORT_SYMBOL(drm_fb_helper_fill_var);
1633
1634 static int drm_fb_helper_probe_connector_modes(struct drm_fb_helper *fb_helper,
1635                                                uint32_t maxX,
1636                                                uint32_t maxY)
1637 {
1638         struct drm_connector *connector;
1639         int count = 0;
1640         int i;
1641
1642         for (i = 0; i < fb_helper->connector_count; i++) {
1643                 connector = fb_helper->connector_info[i]->connector;
1644                 count += connector->funcs->fill_modes(connector, maxX, maxY);
1645         }
1646
1647         return count;
1648 }
1649
1650 struct drm_display_mode *drm_has_preferred_mode(struct drm_fb_helper_connector *fb_connector, int width, int height)
1651 {
1652         struct drm_display_mode *mode;
1653
1654         list_for_each_entry(mode, &fb_connector->connector->modes, head) {
1655                 if (mode->hdisplay > width ||
1656                     mode->vdisplay > height)
1657                         continue;
1658                 if (mode->type & DRM_MODE_TYPE_PREFERRED)
1659                         return mode;
1660         }
1661         return NULL;
1662 }
1663 EXPORT_SYMBOL(drm_has_preferred_mode);
1664
1665 static bool drm_has_cmdline_mode(struct drm_fb_helper_connector *fb_connector)
1666 {
1667         return fb_connector->connector->cmdline_mode.specified;
1668 }
1669
1670 struct drm_display_mode *drm_pick_cmdline_mode(struct drm_fb_helper_connector *fb_helper_conn,
1671                                                       int width, int height)
1672 {
1673         struct drm_cmdline_mode *cmdline_mode;
1674         struct drm_display_mode *mode;
1675         bool prefer_non_interlace;
1676
1677         cmdline_mode = &fb_helper_conn->connector->cmdline_mode;
1678         if (cmdline_mode->specified == false)
1679                 return NULL;
1680
1681         /* attempt to find a matching mode in the list of modes
1682          *  we have gotten so far, if not add a CVT mode that conforms
1683          */
1684         if (cmdline_mode->rb || cmdline_mode->margins)
1685                 goto create_mode;
1686
1687         prefer_non_interlace = !cmdline_mode->interlace;
1688 again:
1689         list_for_each_entry(mode, &fb_helper_conn->connector->modes, head) {
1690                 /* check width/height */
1691                 if (mode->hdisplay != cmdline_mode->xres ||
1692                     mode->vdisplay != cmdline_mode->yres)
1693                         continue;
1694
1695                 if (cmdline_mode->refresh_specified) {
1696                         if (mode->vrefresh != cmdline_mode->refresh)
1697                                 continue;
1698                 }
1699
1700                 if (cmdline_mode->interlace) {
1701                         if (!(mode->flags & DRM_MODE_FLAG_INTERLACE))
1702                                 continue;
1703                 } else if (prefer_non_interlace) {
1704                         if (mode->flags & DRM_MODE_FLAG_INTERLACE)
1705                                 continue;
1706                 }
1707                 return mode;
1708         }
1709
1710         if (prefer_non_interlace) {
1711                 prefer_non_interlace = false;
1712                 goto again;
1713         }
1714
1715 create_mode:
1716         mode = drm_mode_create_from_cmdline_mode(fb_helper_conn->connector->dev,
1717                                                  cmdline_mode);
1718         list_add(&mode->head, &fb_helper_conn->connector->modes);
1719         return mode;
1720 }
1721 EXPORT_SYMBOL(drm_pick_cmdline_mode);
1722
1723 static bool drm_connector_enabled(struct drm_connector *connector, bool strict)
1724 {
1725         bool enable;
1726
1727         if (strict)
1728                 enable = connector->status == connector_status_connected;
1729         else
1730                 enable = connector->status != connector_status_disconnected;
1731
1732         return enable;
1733 }
1734
1735 static void drm_enable_connectors(struct drm_fb_helper *fb_helper,
1736                                   bool *enabled)
1737 {
1738         bool any_enabled = false;
1739         struct drm_connector *connector;
1740         int i = 0;
1741
1742         for (i = 0; i < fb_helper->connector_count; i++) {
1743                 connector = fb_helper->connector_info[i]->connector;
1744                 enabled[i] = drm_connector_enabled(connector, true);
1745                 DRM_DEBUG_KMS("connector %d enabled? %s\n", connector->base.id,
1746                           enabled[i] ? "yes" : "no");
1747                 any_enabled |= enabled[i];
1748         }
1749
1750         if (any_enabled)
1751                 return;
1752
1753         for (i = 0; i < fb_helper->connector_count; i++) {
1754                 connector = fb_helper->connector_info[i]->connector;
1755                 enabled[i] = drm_connector_enabled(connector, false);
1756         }
1757 }
1758
1759 static bool drm_target_cloned(struct drm_fb_helper *fb_helper,
1760                               struct drm_display_mode **modes,
1761                               struct drm_fb_offset *offsets,
1762                               bool *enabled, int width, int height)
1763 {
1764         int count, i, j;
1765         bool can_clone = false;
1766         struct drm_fb_helper_connector *fb_helper_conn;
1767         struct drm_display_mode *dmt_mode, *mode;
1768
1769         /* only contemplate cloning in the single crtc case */
1770         if (fb_helper->crtc_count > 1)
1771                 return false;
1772
1773         count = 0;
1774         for (i = 0; i < fb_helper->connector_count; i++) {
1775                 if (enabled[i])
1776                         count++;
1777         }
1778
1779         /* only contemplate cloning if more than one connector is enabled */
1780         if (count <= 1)
1781                 return false;
1782
1783         /* check the command line or if nothing common pick 1024x768 */
1784         can_clone = true;
1785         for (i = 0; i < fb_helper->connector_count; i++) {
1786                 if (!enabled[i])
1787                         continue;
1788                 fb_helper_conn = fb_helper->connector_info[i];
1789                 modes[i] = drm_pick_cmdline_mode(fb_helper_conn, width, height);
1790                 if (!modes[i]) {
1791                         can_clone = false;
1792                         break;
1793                 }
1794                 for (j = 0; j < i; j++) {
1795                         if (!enabled[j])
1796                                 continue;
1797                         if (!drm_mode_equal(modes[j], modes[i]))
1798                                 can_clone = false;
1799                 }
1800         }
1801
1802         if (can_clone) {
1803                 DRM_DEBUG_KMS("can clone using command line\n");
1804                 return true;
1805         }
1806
1807         /* try and find a 1024x768 mode on each connector */
1808         can_clone = true;
1809         dmt_mode = drm_mode_find_dmt(fb_helper->dev, 1024, 768, 60, false);
1810
1811         for (i = 0; i < fb_helper->connector_count; i++) {
1812
1813                 if (!enabled[i])
1814                         continue;
1815
1816                 fb_helper_conn = fb_helper->connector_info[i];
1817                 list_for_each_entry(mode, &fb_helper_conn->connector->modes, head) {
1818                         if (drm_mode_equal(mode, dmt_mode))
1819                                 modes[i] = mode;
1820                 }
1821                 if (!modes[i])
1822                         can_clone = false;
1823         }
1824
1825         if (can_clone) {
1826                 DRM_DEBUG_KMS("can clone using 1024x768\n");
1827                 return true;
1828         }
1829         DRM_INFO("kms: can't enable cloning when we probably wanted to.\n");
1830         return false;
1831 }
1832
1833 static int drm_get_tile_offsets(struct drm_fb_helper *fb_helper,
1834                                 struct drm_display_mode **modes,
1835                                 struct drm_fb_offset *offsets,
1836                                 int idx,
1837                                 int h_idx, int v_idx)
1838 {
1839         struct drm_fb_helper_connector *fb_helper_conn;
1840         int i;
1841         int hoffset = 0, voffset = 0;
1842
1843         for (i = 0; i < fb_helper->connector_count; i++) {
1844                 fb_helper_conn = fb_helper->connector_info[i];
1845                 if (!fb_helper_conn->connector->has_tile)
1846                         continue;
1847
1848                 if (!modes[i] && (h_idx || v_idx)) {
1849                         DRM_DEBUG_KMS("no modes for connector tiled %d %d\n", i,
1850                                       fb_helper_conn->connector->base.id);
1851                         continue;
1852                 }
1853                 if (fb_helper_conn->connector->tile_h_loc < h_idx)
1854                         hoffset += modes[i]->hdisplay;
1855
1856                 if (fb_helper_conn->connector->tile_v_loc < v_idx)
1857                         voffset += modes[i]->vdisplay;
1858         }
1859         offsets[idx].x = hoffset;
1860         offsets[idx].y = voffset;
1861         DRM_DEBUG_KMS("returned %d %d for %d %d\n", hoffset, voffset, h_idx, v_idx);
1862         return 0;
1863 }
1864
1865 static bool drm_target_preferred(struct drm_fb_helper *fb_helper,
1866                                  struct drm_display_mode **modes,
1867                                  struct drm_fb_offset *offsets,
1868                                  bool *enabled, int width, int height)
1869 {
1870         struct drm_fb_helper_connector *fb_helper_conn;
1871         int i;
1872         uint64_t conn_configured = 0, mask;
1873         int tile_pass = 0;
1874         mask = (1 << fb_helper->connector_count) - 1;
1875 retry:
1876         for (i = 0; i < fb_helper->connector_count; i++) {
1877                 fb_helper_conn = fb_helper->connector_info[i];
1878
1879                 if (conn_configured & (1 << i))
1880                         continue;
1881
1882                 if (enabled[i] == false) {
1883                         conn_configured |= (1 << i);
1884                         continue;
1885                 }
1886
1887                 /* first pass over all the untiled connectors */
1888                 if (tile_pass == 0 && fb_helper_conn->connector->has_tile)
1889                         continue;
1890
1891                 if (tile_pass == 1) {
1892                         if (fb_helper_conn->connector->tile_h_loc != 0 ||
1893                             fb_helper_conn->connector->tile_v_loc != 0)
1894                                 continue;
1895
1896                 } else {
1897                         if (fb_helper_conn->connector->tile_h_loc != tile_pass -1 &&
1898                             fb_helper_conn->connector->tile_v_loc != tile_pass - 1)
1899                         /* if this tile_pass doesn't cover any of the tiles - keep going */
1900                                 continue;
1901
1902                         /* find the tile offsets for this pass - need
1903                            to find all tiles left and above */
1904                         drm_get_tile_offsets(fb_helper, modes, offsets,
1905                                              i, fb_helper_conn->connector->tile_h_loc, fb_helper_conn->connector->tile_v_loc);
1906                 }
1907                 DRM_DEBUG_KMS("looking for cmdline mode on connector %d\n",
1908                               fb_helper_conn->connector->base.id);
1909
1910                 /* got for command line mode first */
1911                 modes[i] = drm_pick_cmdline_mode(fb_helper_conn, width, height);
1912                 if (!modes[i]) {
1913                         DRM_DEBUG_KMS("looking for preferred mode on connector %d %d\n",
1914                                       fb_helper_conn->connector->base.id, fb_helper_conn->connector->tile_group ? fb_helper_conn->connector->tile_group->id : 0);
1915                         modes[i] = drm_has_preferred_mode(fb_helper_conn, width, height);
1916                 }
1917                 /* No preferred modes, pick one off the list */
1918                 if (!modes[i] && !list_empty(&fb_helper_conn->connector->modes)) {
1919                         list_for_each_entry(modes[i], &fb_helper_conn->connector->modes, head)
1920                                 break;
1921                 }
1922                 DRM_DEBUG_KMS("found mode %s\n", modes[i] ? modes[i]->name :
1923                           "none");
1924                 conn_configured |= (1 << i);
1925         }
1926
1927         if ((conn_configured & mask) != mask) {
1928                 tile_pass++;
1929                 goto retry;
1930         }
1931         return true;
1932 }
1933
1934 static int drm_pick_crtcs(struct drm_fb_helper *fb_helper,
1935                           struct drm_fb_helper_crtc **best_crtcs,
1936                           struct drm_display_mode **modes,
1937                           int n, int width, int height)
1938 {
1939         int c, o;
1940         struct drm_connector *connector;
1941         const struct drm_connector_helper_funcs *connector_funcs;
1942         struct drm_encoder *encoder;
1943         int my_score, best_score, score;
1944         struct drm_fb_helper_crtc **crtcs, *crtc;
1945         struct drm_fb_helper_connector *fb_helper_conn;
1946
1947         if (n == fb_helper->connector_count)
1948                 return 0;
1949
1950         fb_helper_conn = fb_helper->connector_info[n];
1951         connector = fb_helper_conn->connector;
1952
1953         best_crtcs[n] = NULL;
1954         best_score = drm_pick_crtcs(fb_helper, best_crtcs, modes, n+1, width, height);
1955         if (modes[n] == NULL)
1956                 return best_score;
1957
1958         crtcs = kzalloc(fb_helper->connector_count *
1959                         sizeof(struct drm_fb_helper_crtc *), GFP_KERNEL);
1960         if (!crtcs)
1961                 return best_score;
1962
1963         my_score = 1;
1964         if (connector->status == connector_status_connected)
1965                 my_score++;
1966         if (drm_has_cmdline_mode(fb_helper_conn))
1967                 my_score++;
1968         if (drm_has_preferred_mode(fb_helper_conn, width, height))
1969                 my_score++;
1970
1971         connector_funcs = connector->helper_private;
1972
1973         /*
1974          * If the DRM device implements atomic hooks and ->best_encoder() is
1975          * NULL we fallback to the default drm_atomic_helper_best_encoder()
1976          * helper.
1977          */
1978         if (fb_helper->dev->mode_config.funcs->atomic_commit &&
1979             !connector_funcs->best_encoder)
1980                 encoder = drm_atomic_helper_best_encoder(connector);
1981         else
1982                 encoder = connector_funcs->best_encoder(connector);
1983
1984         if (!encoder)
1985                 goto out;
1986
1987         /* select a crtc for this connector and then attempt to configure
1988            remaining connectors */
1989         for (c = 0; c < fb_helper->crtc_count; c++) {
1990                 crtc = &fb_helper->crtc_info[c];
1991
1992                 if ((encoder->possible_crtcs & (1 << c)) == 0)
1993                         continue;
1994
1995                 for (o = 0; o < n; o++)
1996                         if (best_crtcs[o] == crtc)
1997                                 break;
1998
1999                 if (o < n) {
2000                         /* ignore cloning unless only a single crtc */
2001                         if (fb_helper->crtc_count > 1)
2002                                 continue;
2003
2004                         if (!drm_mode_equal(modes[o], modes[n]))
2005                                 continue;
2006                 }
2007
2008                 crtcs[n] = crtc;
2009                 memcpy(crtcs, best_crtcs, n * sizeof(struct drm_fb_helper_crtc *));
2010                 score = my_score + drm_pick_crtcs(fb_helper, crtcs, modes, n + 1,
2011                                                   width, height);
2012                 if (score > best_score) {
2013                         best_score = score;
2014                         memcpy(best_crtcs, crtcs,
2015                                fb_helper->connector_count *
2016                                sizeof(struct drm_fb_helper_crtc *));
2017                 }
2018         }
2019 out:
2020         kfree(crtcs);
2021         return best_score;
2022 }
2023
2024 static void drm_setup_crtcs(struct drm_fb_helper *fb_helper)
2025 {
2026         struct drm_device *dev = fb_helper->dev;
2027         struct drm_fb_helper_crtc **crtcs;
2028         struct drm_display_mode **modes;
2029         struct drm_fb_offset *offsets;
2030         struct drm_mode_set *modeset;
2031         bool *enabled;
2032         int width, height;
2033         int i;
2034
2035         DRM_DEBUG_KMS("\n");
2036
2037         width = dev->mode_config.max_width;
2038         height = dev->mode_config.max_height;
2039
2040         crtcs = kcalloc(fb_helper->connector_count,
2041                         sizeof(struct drm_fb_helper_crtc *), GFP_KERNEL);
2042         modes = kcalloc(fb_helper->connector_count,
2043                         sizeof(struct drm_display_mode *), GFP_KERNEL);
2044         offsets = kcalloc(fb_helper->connector_count,
2045                           sizeof(struct drm_fb_offset), GFP_KERNEL);
2046         enabled = kcalloc(fb_helper->connector_count,
2047                           sizeof(bool), GFP_KERNEL);
2048         if (!crtcs || !modes || !enabled || !offsets) {
2049                 DRM_ERROR("Memory allocation failed\n");
2050                 goto out;
2051         }
2052
2053
2054         drm_enable_connectors(fb_helper, enabled);
2055
2056         if (!(fb_helper->funcs->initial_config &&
2057               fb_helper->funcs->initial_config(fb_helper, crtcs, modes,
2058                                                offsets,
2059                                                enabled, width, height))) {
2060                 memset(modes, 0, fb_helper->connector_count*sizeof(modes[0]));
2061                 memset(crtcs, 0, fb_helper->connector_count*sizeof(crtcs[0]));
2062                 memset(offsets, 0, fb_helper->connector_count*sizeof(offsets[0]));
2063
2064                 if (!drm_target_cloned(fb_helper, modes, offsets,
2065                                        enabled, width, height) &&
2066                     !drm_target_preferred(fb_helper, modes, offsets,
2067                                           enabled, width, height))
2068                         DRM_ERROR("Unable to find initial modes\n");
2069
2070                 DRM_DEBUG_KMS("picking CRTCs for %dx%d config\n",
2071                               width, height);
2072
2073                 drm_pick_crtcs(fb_helper, crtcs, modes, 0, width, height);
2074         }
2075
2076         /* need to set the modesets up here for use later */
2077         /* fill out the connector<->crtc mappings into the modesets */
2078         for (i = 0; i < fb_helper->crtc_count; i++) {
2079                 modeset = &fb_helper->crtc_info[i].mode_set;
2080                 modeset->num_connectors = 0;
2081                 modeset->fb = NULL;
2082         }
2083
2084         for (i = 0; i < fb_helper->connector_count; i++) {
2085                 struct drm_display_mode *mode = modes[i];
2086                 struct drm_fb_helper_crtc *fb_crtc = crtcs[i];
2087                 struct drm_fb_offset *offset = &offsets[i];
2088                 modeset = &fb_crtc->mode_set;
2089
2090                 if (mode && fb_crtc) {
2091                         DRM_DEBUG_KMS("desired mode %s set on crtc %d (%d,%d)\n",
2092                                       mode->name, fb_crtc->mode_set.crtc->base.id, offset->x, offset->y);
2093                         fb_crtc->desired_mode = mode;
2094                         fb_crtc->x = offset->x;
2095                         fb_crtc->y = offset->y;
2096                         if (modeset->mode)
2097                                 drm_mode_destroy(dev, modeset->mode);
2098                         modeset->mode = drm_mode_duplicate(dev,
2099                                                            fb_crtc->desired_mode);
2100                         modeset->connectors[modeset->num_connectors++] = fb_helper->connector_info[i]->connector;
2101                         modeset->fb = fb_helper->fb;
2102                         modeset->x = offset->x;
2103                         modeset->y = offset->y;
2104                 }
2105         }
2106
2107         /* Clear out any old modes if there are no more connected outputs. */
2108         for (i = 0; i < fb_helper->crtc_count; i++) {
2109                 modeset = &fb_helper->crtc_info[i].mode_set;
2110                 if (modeset->num_connectors == 0) {
2111                         BUG_ON(modeset->fb);
2112                         if (modeset->mode)
2113                                 drm_mode_destroy(dev, modeset->mode);
2114                         modeset->mode = NULL;
2115                 }
2116         }
2117 out:
2118         kfree(crtcs);
2119         kfree(modes);
2120         kfree(offsets);
2121         kfree(enabled);
2122 }
2123
2124 /**
2125  * drm_fb_helper_initial_config - setup a sane initial connector configuration
2126  * @fb_helper: fb_helper device struct
2127  * @bpp_sel: bpp value to use for the framebuffer configuration
2128  *
2129  * Scans the CRTCs and connectors and tries to put together an initial setup.
2130  * At the moment, this is a cloned configuration across all heads with
2131  * a new framebuffer object as the backing store.
2132  *
2133  * Note that this also registers the fbdev and so allows userspace to call into
2134  * the driver through the fbdev interfaces.
2135  *
2136  * This function will call down into the ->fb_probe callback to let
2137  * the driver allocate and initialize the fbdev info structure and the drm
2138  * framebuffer used to back the fbdev. drm_fb_helper_fill_var() and
2139  * drm_fb_helper_fill_fix() are provided as helpers to setup simple default
2140  * values for the fbdev info structure.
2141  *
2142  * HANG DEBUGGING:
2143  *
2144  * When you have fbcon support built-in or already loaded, this function will do
2145  * a full modeset to setup the fbdev console. Due to locking misdesign in the
2146  * VT/fbdev subsystem that entire modeset sequence has to be done while holding
2147  * console_lock. Until console_unlock is called no dmesg lines will be sent out
2148  * to consoles, not even serial console. This means when your driver crashes,
2149  * you will see absolutely nothing else but a system stuck in this function,
2150  * with no further output. Any kind of printk() you place within your own driver
2151  * or in the drm core modeset code will also never show up.
2152  *
2153  * Standard debug practice is to run the fbcon setup without taking the
2154  * console_lock as a hack, to be able to see backtraces and crashes on the
2155  * serial line. This can be done by setting the fb.lockless_register_fb=1 kernel
2156  * cmdline option.
2157  *
2158  * The other option is to just disable fbdev emulation since very likely the
2159  * first modeset from userspace will crash in the same way, and is even easier
2160  * to debug. This can be done by setting the drm_kms_helper.fbdev_emulation=0
2161  * kernel cmdline option.
2162  *
2163  * RETURNS:
2164  * Zero if everything went ok, nonzero otherwise.
2165  */
2166 int drm_fb_helper_initial_config(struct drm_fb_helper *fb_helper, int bpp_sel)
2167 {
2168         struct drm_device *dev = fb_helper->dev;
2169         int count = 0;
2170
2171         if (!drm_fbdev_emulation)
2172                 return 0;
2173
2174         mutex_lock(&dev->mode_config.mutex);
2175         count = drm_fb_helper_probe_connector_modes(fb_helper,
2176                                                     dev->mode_config.max_width,
2177                                                     dev->mode_config.max_height);
2178         mutex_unlock(&dev->mode_config.mutex);
2179         /*
2180          * we shouldn't end up with no modes here.
2181          */
2182         if (count == 0)
2183                 dev_info(fb_helper->dev->dev, "No connectors reported connected with modes\n");
2184
2185         drm_setup_crtcs(fb_helper);
2186
2187         return drm_fb_helper_single_fb_probe(fb_helper, bpp_sel);
2188 }
2189 EXPORT_SYMBOL(drm_fb_helper_initial_config);
2190
2191 /**
2192  * drm_fb_helper_hotplug_event - respond to a hotplug notification by
2193  *                               probing all the outputs attached to the fb
2194  * @fb_helper: the drm_fb_helper
2195  *
2196  * Scan the connectors attached to the fb_helper and try to put together a
2197  * setup after *notification of a change in output configuration.
2198  *
2199  * Called at runtime, takes the mode config locks to be able to check/change the
2200  * modeset configuration. Must be run from process context (which usually means
2201  * either the output polling work or a work item launched from the driver's
2202  * hotplug interrupt).
2203  *
2204  * Note that drivers may call this even before calling
2205  * drm_fb_helper_initial_config but only after drm_fb_helper_init. This allows
2206  * for a race-free fbcon setup and will make sure that the fbdev emulation will
2207  * not miss any hotplug events.
2208  *
2209  * RETURNS:
2210  * 0 on success and a non-zero error code otherwise.
2211  */
2212 int drm_fb_helper_hotplug_event(struct drm_fb_helper *fb_helper)
2213 {
2214         struct drm_device *dev = fb_helper->dev;
2215         u32 max_width, max_height;
2216
2217         if (!drm_fbdev_emulation)
2218                 return 0;
2219
2220         mutex_lock(&fb_helper->dev->mode_config.mutex);
2221         if (!fb_helper->fb || !drm_fb_helper_is_bound(fb_helper)) {
2222                 fb_helper->delayed_hotplug = true;
2223                 mutex_unlock(&fb_helper->dev->mode_config.mutex);
2224                 return 0;
2225         }
2226         DRM_DEBUG_KMS("\n");
2227
2228         max_width = fb_helper->fb->width;
2229         max_height = fb_helper->fb->height;
2230
2231         drm_fb_helper_probe_connector_modes(fb_helper, max_width, max_height);
2232         mutex_unlock(&fb_helper->dev->mode_config.mutex);
2233
2234         drm_modeset_lock_all(dev);
2235         drm_setup_crtcs(fb_helper);
2236         drm_modeset_unlock_all(dev);
2237         drm_fb_helper_set_par(fb_helper->fbdev);
2238
2239         return 0;
2240 }
2241 EXPORT_SYMBOL(drm_fb_helper_hotplug_event);
2242
2243 /* The Kconfig DRM_KMS_HELPER selects FRAMEBUFFER_CONSOLE (if !EXPERT)
2244  * but the module doesn't depend on any fb console symbols.  At least
2245  * attempt to load fbcon to avoid leaving the system without a usable console.
2246  */
2247 int __init drm_fb_helper_modinit(void)
2248 {
2249 #if defined(CONFIG_FRAMEBUFFER_CONSOLE_MODULE) && !defined(CONFIG_EXPERT)
2250         const char *name = "fbcon";
2251         struct module *fbcon;
2252
2253         mutex_lock(&module_mutex);
2254         fbcon = find_module(name);
2255         mutex_unlock(&module_mutex);
2256
2257         if (!fbcon)
2258                 request_module_nowait(name);
2259 #endif
2260         return 0;
2261 }
2262 EXPORT_SYMBOL(drm_fb_helper_modinit);