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/console.h>
  33 #include <linux/kernel.h>
  34 #include <linux/sysrq.h>
  35 #include <linux/slab.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 #include "drm_crtc_helper_internal.h"
  45
  46 static bool drm_fbdev_emulation = true;
  47 module_param_named(fbdev_emulation, drm_fbdev_emulation, bool, 0600);
  48 MODULE_PARM_DESC(fbdev_emulation,
  49                  "Enable legacy fbdev emulation [default=true]");
  50
  51 static LIST_HEAD(kernel_fb_helper_list);
  52 static DEFINE_MUTEX(kernel_fb_helper_lock);
  53
  54 /**
  55  * DOC: fbdev helpers
  56  *
  57  * The fb helper functions are useful to provide an fbdev on top of a drm kernel
  58  * mode setting driver. They can be used mostly independently from the crtc
  59  * helper functions used by many drivers to implement the kernel mode setting
  60  * interfaces.
  61  *
  62  * Initialization is done as a four-step process with drm_fb_helper_prepare(),
  63  * drm_fb_helper_init(), drm_fb_helper_single_add_all_connectors() and
  64  * drm_fb_helper_initial_config(). Drivers with fancier requirements than the
  65  * default behaviour can override the third step with their own code.
  66  * Teardown is done with drm_fb_helper_fini().
  67  *
  68  * At runtime drivers should restore the fbdev console by calling
  69  * drm_fb_helper_restore_fbdev_mode_unlocked() from their &drm_driver.lastclose
  70  * callback.  They should also notify the fb helper code from updates to the
  71  * output configuration by calling drm_fb_helper_hotplug_event(). For easier
  72  * integration with the output polling code in drm_crtc_helper.c the modeset
  73  * code provides a &drm_mode_config_funcs.output_poll_changed callback.
  74  *
  75  * All other functions exported by the fb helper library can be used to
  76  * implement the fbdev driver interface by the driver.
  77  *
  78  * It is possible, though perhaps somewhat tricky, to implement race-free
  79  * hotplug detection using the fbdev helpers. The drm_fb_helper_prepare()
  80  * helper must be called first to initialize the minimum required to make
  81  * hotplug detection work. Drivers also need to make sure to properly set up
  82  * the &drm_mode_config.funcs member. After calling drm_kms_helper_poll_init()
  83  * it is safe to enable interrupts and start processing hotplug events. At the
  84  * same time, drivers should initialize all modeset objects such as CRTCs,
  85  * encoders and connectors. To finish up the fbdev helper initialization, the
  86  * drm_fb_helper_init() function is called. To probe for all attached displays
  87  * and set up an initial configuration using the detected hardware, drivers
  88  * should call drm_fb_helper_single_add_all_connectors() followed by
  89  * drm_fb_helper_initial_config().
  90  *
  91  * If &drm_framebuffer_funcs.dirty is set, the
  92  * drm_fb_helper_{cfb,sys}_{write,fillrect,copyarea,imageblit} functions will
  93  * accumulate changes and schedule &drm_fb_helper.dirty_work to run right
  94  * away. This worker then calls the dirty() function ensuring that it will
  95  * always run in process context since the fb_*() function could be running in
  96  * atomic context. If drm_fb_helper_deferred_io() is used as the deferred_io
  97  * callback it will also schedule dirty_work with the damage collected from the
  98  * mmap page writes.
  99  */
 100
 101 #define drm_fb_helper_for_each_connector(fbh, i__) \
 102         for (({ lockdep_assert_held(&(fbh)->dev->mode_config.mutex); }), \
 103              i__ = 0; i__ < (fbh)->connector_count; i__++)
 104
 105 /**
 106  * drm_fb_helper_single_add_all_connectors() - add all connectors to fbdev
 107  *                                             emulation helper
 108  * @fb_helper: fbdev initialized with drm_fb_helper_init
 109  *
 110  * This functions adds all the available connectors for use with the given
 111  * fb_helper. This is a separate step to allow drivers to freely assign
 112  * connectors to the fbdev, e.g. if some are reserved for special purposes or
 113  * not adequate to be used for the fbcon.
 114  *
 115  * This function is protected against concurrent connector hotadds/removals
 116  * using drm_fb_helper_add_one_connector() and
 117  * drm_fb_helper_remove_one_connector().
 118  */
 119 int drm_fb_helper_single_add_all_connectors(struct drm_fb_helper *fb_helper)
 120 {
 121         struct drm_device *dev = fb_helper->dev;
 122         struct drm_connector *connector;
 123         struct drm_connector_list_iter conn_iter;
 124         int i, ret = 0;
 125
 126         if (!drm_fbdev_emulation)
 127                 return 0;
 128
 129         mutex_lock(&dev->mode_config.mutex);
 130         drm_connector_list_iter_get(dev, &conn_iter);
 131         drm_for_each_connector_iter(connector, &conn_iter) {
 132                 ret = drm_fb_helper_add_one_connector(fb_helper, connector);
 133
 134                 if (ret)
 135                         goto fail;
 136         }
 137         goto out;
 138
 139 fail:
 140         drm_fb_helper_for_each_connector(fb_helper, i) {
 141                 struct drm_fb_helper_connector *fb_helper_connector =
 142                         fb_helper->connector_info[i];
 143
 144                 drm_connector_unreference(fb_helper_connector->connector);
 145
 146                 kfree(fb_helper_connector);
 147                 fb_helper->connector_info[i] = NULL;
 148         }
 149         fb_helper->connector_count = 0;
 150 out:
 151         drm_connector_list_iter_put(&conn_iter);
 152         mutex_unlock(&dev->mode_config.mutex);
 153
 154         return ret;
 155 }
 156 EXPORT_SYMBOL(drm_fb_helper_single_add_all_connectors);
 157
 158 int drm_fb_helper_add_one_connector(struct drm_fb_helper *fb_helper, struct drm_connector *connector)
 159 {
 160         struct drm_fb_helper_connector **temp;
 161         struct drm_fb_helper_connector *fb_helper_connector;
 162
 163         if (!drm_fbdev_emulation)
 164                 return 0;
 165
 166         WARN_ON(!mutex_is_locked(&fb_helper->dev->mode_config.mutex));
 167         if (fb_helper->connector_count + 1 > fb_helper->connector_info_alloc_count) {
 168                 temp = krealloc(fb_helper->connector_info, sizeof(struct drm_fb_helper_connector *) * (fb_helper->connector_count + 1), GFP_KERNEL);
 169                 if (!temp)
 170                         return -ENOMEM;
 171
 172                 fb_helper->connector_info_alloc_count = fb_helper->connector_count + 1;
 173                 fb_helper->connector_info = temp;
 174         }
 175
 176
 177         fb_helper_connector = kzalloc(sizeof(struct drm_fb_helper_connector), GFP_KERNEL);
 178         if (!fb_helper_connector)
 179                 return -ENOMEM;
 180
 181         drm_connector_reference(connector);
 182         fb_helper_connector->connector = connector;
 183         fb_helper->connector_info[fb_helper->connector_count++] = fb_helper_connector;
 184         return 0;
 185 }
 186 EXPORT_SYMBOL(drm_fb_helper_add_one_connector);
 187
 188 int drm_fb_helper_remove_one_connector(struct drm_fb_helper *fb_helper,
 189                                        struct drm_connector *connector)
 190 {
 191         struct drm_fb_helper_connector *fb_helper_connector;
 192         int i, j;
 193
 194         if (!drm_fbdev_emulation)
 195                 return 0;
 196
 197         WARN_ON(!mutex_is_locked(&fb_helper->dev->mode_config.mutex));
 198
 199         for (i = 0; i < fb_helper->connector_count; i++) {
 200                 if (fb_helper->connector_info[i]->connector == connector)
 201                         break;
 202         }
 203
 204         if (i == fb_helper->connector_count)
 205                 return -EINVAL;
 206         fb_helper_connector = fb_helper->connector_info[i];
 207         drm_connector_unreference(fb_helper_connector->connector);
 208
 209         for (j = i + 1; j < fb_helper->connector_count; j++) {
 210                 fb_helper->connector_info[j - 1] = fb_helper->connector_info[j];
 211         }
 212         fb_helper->connector_count--;
 213         kfree(fb_helper_connector);
 214
 215         return 0;
 216 }
 217 EXPORT_SYMBOL(drm_fb_helper_remove_one_connector);
 218
 219 static void drm_fb_helper_save_lut_atomic(struct drm_crtc *crtc, struct drm_fb_helper *helper)
 220 {
 221         uint16_t *r_base, *g_base, *b_base;
 222         int i;
 223
 224         if (helper->funcs->gamma_get == NULL)
 225                 return;
 226
 227         r_base = crtc->gamma_store;
 228         g_base = r_base + crtc->gamma_size;
 229         b_base = g_base + crtc->gamma_size;
 230
 231         for (i = 0; i < crtc->gamma_size; i++)
 232                 helper->funcs->gamma_get(crtc, &r_base[i], &g_base[i], &b_base[i], i);
 233 }
 234
 235 static void drm_fb_helper_restore_lut_atomic(struct drm_crtc *crtc)
 236 {
 237         uint16_t *r_base, *g_base, *b_base;
 238
 239         if (crtc->funcs->gamma_set == NULL)
 240                 return;
 241
 242         r_base = crtc->gamma_store;
 243         g_base = r_base + crtc->gamma_size;
 244         b_base = g_base + crtc->gamma_size;
 245
 246         crtc->funcs->gamma_set(crtc, r_base, g_base, b_base, crtc->gamma_size);
 247 }
 248
 249 /**
 250  * drm_fb_helper_debug_enter - implementation for &fb_ops.fb_debug_enter
 251  * @info: fbdev registered by the helper
 252  */
 253 int drm_fb_helper_debug_enter(struct fb_info *info)
 254 {
 255         struct drm_fb_helper *helper = info->par;
 256         const struct drm_crtc_helper_funcs *funcs;
 257         int i;
 258
 259         list_for_each_entry(helper, &kernel_fb_helper_list, kernel_fb_list) {
 260                 for (i = 0; i < helper->crtc_count; i++) {
 261                         struct drm_mode_set *mode_set =
 262                                 &helper->crtc_info[i].mode_set;
 263
 264                         if (!mode_set->crtc->enabled)
 265                                 continue;
 266
 267                         funcs = mode_set->crtc->helper_private;
 268                         if (funcs->mode_set_base_atomic == NULL)
 269                                 continue;
 270
 271                         drm_fb_helper_save_lut_atomic(mode_set->crtc, helper);
 272                         funcs->mode_set_base_atomic(mode_set->crtc,
 273                                                     mode_set->fb,
 274                                                     mode_set->x,
 275                                                     mode_set->y,
 276                                                     ENTER_ATOMIC_MODE_SET);
 277                 }
 278         }
 279
 280         return 0;
 281 }
 282 EXPORT_SYMBOL(drm_fb_helper_debug_enter);
 283
 284 /* Find the real fb for a given fb helper CRTC */
 285 static struct drm_framebuffer *drm_mode_config_fb(struct drm_crtc *crtc)
 286 {
 287         struct drm_device *dev = crtc->dev;
 288         struct drm_crtc *c;
 289
 290         drm_for_each_crtc(c, dev) {
 291                 if (crtc->base.id == c->base.id)
 292                         return c->primary->fb;
 293         }
 294
 295         return NULL;
 296 }
 297
 298 /**
 299  * drm_fb_helper_debug_leave - implementation for &fb_ops.fb_debug_leave
 300  * @info: fbdev registered by the helper
 301  */
 302 int drm_fb_helper_debug_leave(struct fb_info *info)
 303 {
 304         struct drm_fb_helper *helper = info->par;
 305         struct drm_crtc *crtc;
 306         const struct drm_crtc_helper_funcs *funcs;
 307         struct drm_framebuffer *fb;
 308         int i;
 309
 310         for (i = 0; i < helper->crtc_count; i++) {
 311                 struct drm_mode_set *mode_set = &helper->crtc_info[i].mode_set;
 312                 crtc = mode_set->crtc;
 313                 funcs = crtc->helper_private;
 314                 fb = drm_mode_config_fb(crtc);
 315
 316                 if (!crtc->enabled)
 317                         continue;
 318
 319                 if (!fb) {
 320                         DRM_ERROR("no fb to restore??\n");
 321                         continue;
 322                 }
 323
 324                 if (funcs->mode_set_base_atomic == NULL)
 325                         continue;
 326
 327                 drm_fb_helper_restore_lut_atomic(mode_set->crtc);
 328                 funcs->mode_set_base_atomic(mode_set->crtc, fb, crtc->x,
 329                                             crtc->y, LEAVE_ATOMIC_MODE_SET);
 330         }
 331
 332         return 0;
 333 }
 334 EXPORT_SYMBOL(drm_fb_helper_debug_leave);
 335
 336 static int restore_fbdev_mode_atomic(struct drm_fb_helper *fb_helper)
 337 {
 338         struct drm_device *dev = fb_helper->dev;
 339         struct drm_plane *plane;
 340         struct drm_atomic_state *state;
 341         int i, ret;
 342         unsigned plane_mask;
 343
 344         state = drm_atomic_state_alloc(dev);
 345         if (!state)
 346                 return -ENOMEM;
 347
 348         state->acquire_ctx = dev->mode_config.acquire_ctx;
 349 retry:
 350         plane_mask = 0;
 351         drm_for_each_plane(plane, dev) {
 352                 struct drm_plane_state *plane_state;
 353
 354                 plane_state = drm_atomic_get_plane_state(state, plane);
 355                 if (IS_ERR(plane_state)) {
 356                         ret = PTR_ERR(plane_state);
 357                         goto fail;
 358                 }
 359
 360                 plane_state->rotation = DRM_ROTATE_0;
 361
 362                 plane->old_fb = plane->fb;
 363                 plane_mask |= 1 << drm_plane_index(plane);
 364
 365                 /* disable non-primary: */
 366                 if (plane->type == DRM_PLANE_TYPE_PRIMARY)
 367                         continue;
 368
 369                 ret = __drm_atomic_helper_disable_plane(plane, plane_state);
 370                 if (ret != 0)
 371                         goto fail;
 372         }
 373
 374         for(i = 0; i < fb_helper->crtc_count; i++) {
 375                 struct drm_mode_set *mode_set = &fb_helper->crtc_info[i].mode_set;
 376
 377                 ret = __drm_atomic_helper_set_config(mode_set, state);
 378                 if (ret != 0)
 379                         goto fail;
 380         }
 381
 382         ret = drm_atomic_commit(state);
 383
 384 fail:
 385         drm_atomic_clean_old_fb(dev, plane_mask, ret);
 386
 387         if (ret == -EDEADLK)
 388                 goto backoff;
 389
 390         drm_atomic_state_put(state);
 391         return ret;
 392
 393 backoff:
 394         drm_atomic_state_clear(state);
 395         drm_atomic_legacy_backoff(state);
 396
 397         goto retry;
 398 }
 399
 400 static int restore_fbdev_mode(struct drm_fb_helper *fb_helper)
 401 {
 402         struct drm_device *dev = fb_helper->dev;
 403         struct drm_plane *plane;
 404         int i;
 405
 406         drm_warn_on_modeset_not_all_locked(dev);
 407
 408         if (drm_drv_uses_atomic_modeset(dev))
 409                 return restore_fbdev_mode_atomic(fb_helper);
 410
 411         drm_for_each_plane(plane, dev) {
 412                 if (plane->type != DRM_PLANE_TYPE_PRIMARY)
 413                         drm_plane_force_disable(plane);
 414
 415                 if (plane->rotation_property)
 416                         drm_mode_plane_set_obj_prop(plane,
 417                                                     plane->rotation_property,
 418                                                     DRM_ROTATE_0);
 419         }
 420
 421         for (i = 0; i < fb_helper->crtc_count; i++) {
 422                 struct drm_mode_set *mode_set = &fb_helper->crtc_info[i].mode_set;
 423                 struct drm_crtc *crtc = mode_set->crtc;
 424                 int ret;
 425
 426                 if (crtc->funcs->cursor_set2) {
 427                         ret = crtc->funcs->cursor_set2(crtc, NULL, 0, 0, 0, 0, 0);
 428                         if (ret)
 429                                 return ret;
 430                 } else if (crtc->funcs->cursor_set) {
 431                         ret = crtc->funcs->cursor_set(crtc, NULL, 0, 0, 0);
 432                         if (ret)
 433                                 return ret;
 434                 }
 435
 436                 ret = drm_mode_set_config_internal(mode_set);
 437                 if (ret)
 438                         return ret;
 439         }
 440
 441         return 0;
 442 }
 443
 444 /**
 445  * drm_fb_helper_restore_fbdev_mode_unlocked - restore fbdev configuration
 446  * @fb_helper: fbcon to restore
 447  *
 448  * This should be called from driver's drm &drm_driver.lastclose callback
 449  * when implementing an fbcon on top of kms using this helper. This ensures that
 450  * the user isn't greeted with a black screen when e.g. X dies.
 451  *
 452  * RETURNS:
 453  * Zero if everything went ok, negative error code otherwise.
 454  */
 455 int drm_fb_helper_restore_fbdev_mode_unlocked(struct drm_fb_helper *fb_helper)
 456 {
 457         struct drm_device *dev = fb_helper->dev;
 458         bool do_delayed;
 459         int ret;
 460
 461         if (!drm_fbdev_emulation)
 462                 return -ENODEV;
 463
 464         drm_modeset_lock_all(dev);
 465         ret = restore_fbdev_mode(fb_helper);
 466
 467         do_delayed = fb_helper->delayed_hotplug;
 468         if (do_delayed)
 469                 fb_helper->delayed_hotplug = false;
 470         drm_modeset_unlock_all(dev);
 471
 472         if (do_delayed)
 473                 drm_fb_helper_hotplug_event(fb_helper);
 474         return ret;
 475 }
 476 EXPORT_SYMBOL(drm_fb_helper_restore_fbdev_mode_unlocked);
 477
 478 static bool drm_fb_helper_is_bound(struct drm_fb_helper *fb_helper)
 479 {
 480         struct drm_device *dev = fb_helper->dev;
 481         struct drm_crtc *crtc;
 482         int bound = 0, crtcs_bound = 0;
 483
 484         /* Sometimes user space wants everything disabled, so don't steal the
 485          * display if there's a master. */
 486         if (READ_ONCE(dev->master))
 487                 return false;
 488
 489         drm_for_each_crtc(crtc, dev) {
 490                 if (crtc->primary->fb)
 491                         crtcs_bound++;
 492                 if (crtc->primary->fb == fb_helper->fb)
 493                         bound++;
 494         }
 495
 496         if (bound < crtcs_bound)
 497                 return false;
 498
 499         return true;
 500 }
 501
 502 #ifdef CONFIG_MAGIC_SYSRQ
 503 /*
 504  * restore fbcon display for all kms driver's using this helper, used for sysrq
 505  * and panic handling.
 506  */
 507 static bool drm_fb_helper_force_kernel_mode(void)
 508 {
 509         bool ret, error = false;
 510         struct drm_fb_helper *helper;
 511
 512         if (list_empty(&kernel_fb_helper_list))
 513                 return false;
 514
 515         list_for_each_entry(helper, &kernel_fb_helper_list, kernel_fb_list) {
 516                 struct drm_device *dev = helper->dev;
 517
 518                 if (dev->switch_power_state == DRM_SWITCH_POWER_OFF)
 519                         continue;
 520
 521                 drm_modeset_lock_all(dev);
 522                 ret = restore_fbdev_mode(helper);
 523                 if (ret)
 524                         error = true;
 525                 drm_modeset_unlock_all(dev);
 526         }
 527         return error;
 528 }
 529
 530 static void drm_fb_helper_restore_work_fn(struct work_struct *ignored)
 531 {
 532         bool ret;
 533         ret = drm_fb_helper_force_kernel_mode();
 534         if (ret == true)
 535                 DRM_ERROR("Failed to restore crtc configuration\n");
 536 }
 537 static DECLARE_WORK(drm_fb_helper_restore_work, drm_fb_helper_restore_work_fn);
 538
 539 static void drm_fb_helper_sysrq(int dummy1)
 540 {
 541         schedule_work(&drm_fb_helper_restore_work);
 542 }
 543
 544 static struct sysrq_key_op sysrq_drm_fb_helper_restore_op = {
 545         .handler = drm_fb_helper_sysrq,
 546         .help_msg = "force-fb(V)",
 547         .action_msg = "Restore framebuffer console",
 548 };
 549 #else
 550 static struct sysrq_key_op sysrq_drm_fb_helper_restore_op = { };
 551 #endif
 552
 553 static void drm_fb_helper_dpms(struct fb_info *info, int dpms_mode)
 554 {
 555         struct drm_fb_helper *fb_helper = info->par;
 556         struct drm_device *dev = fb_helper->dev;
 557         struct drm_crtc *crtc;
 558         struct drm_connector *connector;
 559         int i, j;
 560
 561         /*
 562          * For each CRTC in this fb, turn the connectors on/off.
 563          */
 564         drm_modeset_lock_all(dev);
 565         if (!drm_fb_helper_is_bound(fb_helper)) {
 566                 drm_modeset_unlock_all(dev);
 567                 return;
 568         }
 569
 570         for (i = 0; i < fb_helper->crtc_count; i++) {
 571                 crtc = fb_helper->crtc_info[i].mode_set.crtc;
 572
 573                 if (!crtc->enabled)
 574                         continue;
 575
 576                 /* Walk the connectors & encoders on this fb turning them on/off */
 577                 drm_fb_helper_for_each_connector(fb_helper, j) {
 578                         connector = fb_helper->connector_info[j]->connector;
 579                         connector->funcs->dpms(connector, dpms_mode);
 580                         drm_object_property_set_value(&connector->base,
 581                                 dev->mode_config.dpms_property, dpms_mode);
 582                 }
 583         }
 584         drm_modeset_unlock_all(dev);
 585 }
 586
 587 /**
 588  * drm_fb_helper_blank - implementation for &fb_ops.fb_blank
 589  * @blank: desired blanking state
 590  * @info: fbdev registered by the helper
 591  */
 592 int drm_fb_helper_blank(int blank, struct fb_info *info)
 593 {
 594         if (oops_in_progress)
 595                 return -EBUSY;
 596
 597         switch (blank) {
 598         /* Display: On; HSync: On, VSync: On */
 599         case FB_BLANK_UNBLANK:
 600                 drm_fb_helper_dpms(info, DRM_MODE_DPMS_ON);
 601                 break;
 602         /* Display: Off; HSync: On, VSync: On */
 603         case FB_BLANK_NORMAL:
 604                 drm_fb_helper_dpms(info, DRM_MODE_DPMS_STANDBY);
 605                 break;
 606         /* Display: Off; HSync: Off, VSync: On */
 607         case FB_BLANK_HSYNC_SUSPEND:
 608                 drm_fb_helper_dpms(info, DRM_MODE_DPMS_STANDBY);
 609                 break;
 610         /* Display: Off; HSync: On, VSync: Off */
 611         case FB_BLANK_VSYNC_SUSPEND:
 612                 drm_fb_helper_dpms(info, DRM_MODE_DPMS_SUSPEND);
 613                 break;
 614         /* Display: Off; HSync: Off, VSync: Off */
 615         case FB_BLANK_POWERDOWN:
 616                 drm_fb_helper_dpms(info, DRM_MODE_DPMS_OFF);
 617                 break;
 618         }
 619         return 0;
 620 }
 621 EXPORT_SYMBOL(drm_fb_helper_blank);
 622
 623 static void drm_fb_helper_modeset_release(struct drm_fb_helper *helper,
 624                                           struct drm_mode_set *modeset)
 625 {
 626         int i;
 627
 628         for (i = 0; i < modeset->num_connectors; i++) {
 629                 drm_connector_unreference(modeset->connectors[i]);
 630                 modeset->connectors[i] = NULL;
 631         }
 632         modeset->num_connectors = 0;
 633
 634         drm_mode_destroy(helper->dev, modeset->mode);
 635         modeset->mode = NULL;
 636
 637         /* FIXME should hold a ref? */
 638         modeset->fb = NULL;
 639 }
 640
 641 static void drm_fb_helper_crtc_free(struct drm_fb_helper *helper)
 642 {
 643         int i;
 644
 645         for (i = 0; i < helper->connector_count; i++) {
 646                 drm_connector_unreference(helper->connector_info[i]->connector);
 647                 kfree(helper->connector_info[i]);
 648         }
 649         kfree(helper->connector_info);
 650
 651         for (i = 0; i < helper->crtc_count; i++) {
 652                 struct drm_mode_set *modeset = &helper->crtc_info[i].mode_set;
 653
 654                 drm_fb_helper_modeset_release(helper, modeset);
 655                 kfree(modeset->connectors);
 656         }
 657         kfree(helper->crtc_info);
 658 }
 659
 660 static void drm_fb_helper_resume_worker(struct work_struct *work)
 661 {
 662         struct drm_fb_helper *helper = container_of(work, struct drm_fb_helper,
 663                                                     resume_work);
 664
 665         console_lock();
 666         fb_set_suspend(helper->fbdev, 0);
 667         console_unlock();
 668 }
 669
 670 static void drm_fb_helper_dirty_work(struct work_struct *work)
 671 {
 672         struct drm_fb_helper *helper = container_of(work, struct drm_fb_helper,
 673                                                     dirty_work);
 674         struct drm_clip_rect *clip = &helper->dirty_clip;
 675         struct drm_clip_rect clip_copy;
 676         unsigned long flags;
 677
 678         spin_lock_irqsave(&helper->dirty_lock, flags);
 679         clip_copy = *clip;
 680         clip->x1 = clip->y1 = ~0;
 681         clip->x2 = clip->y2 = 0;
 682         spin_unlock_irqrestore(&helper->dirty_lock, flags);
 683
 684         /* call dirty callback only when it has been really touched */
 685         if (clip_copy.x1 < clip_copy.x2 && clip_copy.y1 < clip_copy.y2)
 686                 helper->fb->funcs->dirty(helper->fb, NULL, 0, 0, &clip_copy, 1);
 687 }
 688
 689 /**
 690  * drm_fb_helper_prepare - setup a drm_fb_helper structure
 691  * @dev: DRM device
 692  * @helper: driver-allocated fbdev helper structure to set up
 693  * @funcs: pointer to structure of functions associate with this helper
 694  *
 695  * Sets up the bare minimum to make the framebuffer helper usable. This is
 696  * useful to implement race-free initialization of the polling helpers.
 697  */
 698 void drm_fb_helper_prepare(struct drm_device *dev, struct drm_fb_helper *helper,
 699                            const struct drm_fb_helper_funcs *funcs)
 700 {
 701         INIT_LIST_HEAD(&helper->kernel_fb_list);
 702         spin_lock_init(&helper->dirty_lock);
 703         INIT_WORK(&helper->resume_work, drm_fb_helper_resume_worker);
 704         INIT_WORK(&helper->dirty_work, drm_fb_helper_dirty_work);
 705         helper->dirty_clip.x1 = helper->dirty_clip.y1 = ~0;
 706         helper->funcs = funcs;
 707         helper->dev = dev;
 708 }
 709 EXPORT_SYMBOL(drm_fb_helper_prepare);
 710
 711 /**
 712  * drm_fb_helper_init - initialize a drm_fb_helper structure
 713  * @dev: drm device
 714  * @fb_helper: driver-allocated fbdev helper structure to initialize
 715  * @max_conn_count: max connector count
 716  *
 717  * This allocates the structures for the fbdev helper with the given limits.
 718  * Note that this won't yet touch the hardware (through the driver interfaces)
 719  * nor register the fbdev. This is only done in drm_fb_helper_initial_config()
 720  * to allow driver writes more control over the exact init sequence.
 721  *
 722  * Drivers must call drm_fb_helper_prepare() before calling this function.
 723  *
 724  * RETURNS:
 725  * Zero if everything went ok, nonzero otherwise.
 726  */
 727 int drm_fb_helper_init(struct drm_device *dev,
 728                        struct drm_fb_helper *fb_helper,
 729                        int max_conn_count)
 730 {
 731         struct drm_crtc *crtc;
 732         struct drm_mode_config *config = &dev->mode_config;
 733         int i;
 734
 735         if (!drm_fbdev_emulation)
 736                 return 0;
 737
 738         if (!max_conn_count)
 739                 return -EINVAL;
 740
 741         fb_helper->crtc_info = kcalloc(config->num_crtc, sizeof(struct drm_fb_helper_crtc), GFP_KERNEL);
 742         if (!fb_helper->crtc_info)
 743                 return -ENOMEM;
 744
 745         fb_helper->crtc_count = config->num_crtc;
 746         fb_helper->connector_info = kcalloc(dev->mode_config.num_connector, sizeof(struct drm_fb_helper_connector *), GFP_KERNEL);
 747         if (!fb_helper->connector_info) {
 748                 kfree(fb_helper->crtc_info);
 749                 return -ENOMEM;
 750         }
 751         fb_helper->connector_info_alloc_count = dev->mode_config.num_connector;
 752         fb_helper->connector_count = 0;
 753
 754         for (i = 0; i < fb_helper->crtc_count; i++) {
 755                 fb_helper->crtc_info[i].mode_set.connectors =
 756                         kcalloc(max_conn_count,
 757                                 sizeof(struct drm_connector *),
 758                                 GFP_KERNEL);
 759
 760                 if (!fb_helper->crtc_info[i].mode_set.connectors)
 761                         goto out_free;
 762                 fb_helper->crtc_info[i].mode_set.num_connectors = 0;
 763         }
 764
 765         i = 0;
 766         drm_for_each_crtc(crtc, dev) {
 767                 fb_helper->crtc_info[i].mode_set.crtc = crtc;
 768                 i++;
 769         }
 770
 771         return 0;
 772 out_free:
 773         drm_fb_helper_crtc_free(fb_helper);
 774         return -ENOMEM;
 775 }
 776 EXPORT_SYMBOL(drm_fb_helper_init);
 777
 778 /**
 779  * drm_fb_helper_alloc_fbi - allocate fb_info and some of its members
 780  * @fb_helper: driver-allocated fbdev helper
 781  *
 782  * A helper to alloc fb_info and the members cmap and apertures. Called
 783  * by the driver within the fb_probe fb_helper callback function.
 784  *
 785  * RETURNS:
 786  * fb_info pointer if things went okay, pointer containing error code
 787  * otherwise
 788  */
 789 struct fb_info *drm_fb_helper_alloc_fbi(struct drm_fb_helper *fb_helper)
 790 {
 791         struct device *dev = fb_helper->dev->dev;
 792         struct fb_info *info;
 793         int ret;
 794
 795         info = framebuffer_alloc(0, dev);
 796         if (!info)
 797                 return ERR_PTR(-ENOMEM);
 798
 799         ret = fb_alloc_cmap(&info->cmap, 256, 0);
 800         if (ret)
 801                 goto err_release;
 802
 803         info->apertures = alloc_apertures(1);
 804         if (!info->apertures) {
 805                 ret = -ENOMEM;
 806                 goto err_free_cmap;
 807         }
 808
 809         fb_helper->fbdev = info;
 810
 811         return info;
 812
 813 err_free_cmap:
 814         fb_dealloc_cmap(&info->cmap);
 815 err_release:
 816         framebuffer_release(info);
 817         return ERR_PTR(ret);
 818 }
 819 EXPORT_SYMBOL(drm_fb_helper_alloc_fbi);
 820
 821 /**
 822  * drm_fb_helper_unregister_fbi - unregister fb_info framebuffer device
 823  * @fb_helper: driver-allocated fbdev helper
 824  *
 825  * A wrapper around unregister_framebuffer, to release the fb_info
 826  * framebuffer device
 827  */
 828 void drm_fb_helper_unregister_fbi(struct drm_fb_helper *fb_helper)
 829 {
 830         if (fb_helper && fb_helper->fbdev)
 831                 unregister_framebuffer(fb_helper->fbdev);
 832 }
 833 EXPORT_SYMBOL(drm_fb_helper_unregister_fbi);
 834
 835 /**
 836  * drm_fb_helper_release_fbi - dealloc fb_info and its members
 837  * @fb_helper: driver-allocated fbdev helper
 838  *
 839  * A helper to free memory taken by fb_info and the members cmap and
 840  * apertures
 841  */
 842 void drm_fb_helper_release_fbi(struct drm_fb_helper *fb_helper)
 843 {
 844         if (fb_helper) {
 845                 struct fb_info *info = fb_helper->fbdev;
 846
 847                 if (info) {
 848                         if (info->cmap.len)
 849                                 fb_dealloc_cmap(&info->cmap);
 850                         framebuffer_release(info);
 851                 }
 852
 853                 fb_helper->fbdev = NULL;
 854         }
 855 }
 856 EXPORT_SYMBOL(drm_fb_helper_release_fbi);
 857
 858 void drm_fb_helper_fini(struct drm_fb_helper *fb_helper)
 859 {
 860         if (!drm_fbdev_emulation)
 861                 return;
 862
 863         cancel_work_sync(&fb_helper->resume_work);
 864         cancel_work_sync(&fb_helper->dirty_work);
 865
 866         mutex_lock(&kernel_fb_helper_lock);
 867         if (!list_empty(&fb_helper->kernel_fb_list)) {
 868                 list_del(&fb_helper->kernel_fb_list);
 869                 if (list_empty(&kernel_fb_helper_list)) {
 870                         unregister_sysrq_key('v', &sysrq_drm_fb_helper_restore_op);
 871                 }
 872         }
 873         mutex_unlock(&kernel_fb_helper_lock);
 874
 875         drm_fb_helper_crtc_free(fb_helper);
 876
 877 }
 878 EXPORT_SYMBOL(drm_fb_helper_fini);
 879
 880 /**
 881  * drm_fb_helper_unlink_fbi - wrapper around unlink_framebuffer
 882  * @fb_helper: driver-allocated fbdev helper
 883  *
 884  * A wrapper around unlink_framebuffer implemented by fbdev core
 885  */
 886 void drm_fb_helper_unlink_fbi(struct drm_fb_helper *fb_helper)
 887 {
 888         if (fb_helper && fb_helper->fbdev)
 889                 unlink_framebuffer(fb_helper->fbdev);
 890 }
 891 EXPORT_SYMBOL(drm_fb_helper_unlink_fbi);
 892
 893 static void drm_fb_helper_dirty(struct fb_info *info, u32 x, u32 y,
 894                                 u32 width, u32 height)
 895 {
 896         struct drm_fb_helper *helper = info->par;
 897         struct drm_clip_rect *clip = &helper->dirty_clip;
 898         unsigned long flags;
 899
 900         if (!helper->fb->funcs->dirty)
 901                 return;
 902
 903         spin_lock_irqsave(&helper->dirty_lock, flags);
 904         clip->x1 = min_t(u32, clip->x1, x);
 905         clip->y1 = min_t(u32, clip->y1, y);
 906         clip->x2 = max_t(u32, clip->x2, x + width);
 907         clip->y2 = max_t(u32, clip->y2, y + height);
 908         spin_unlock_irqrestore(&helper->dirty_lock, flags);
 909
 910         schedule_work(&helper->dirty_work);
 911 }
 912
 913 /**
 914  * drm_fb_helper_deferred_io() - fbdev deferred_io callback function
 915  * @info: fb_info struct pointer
 916  * @pagelist: list of dirty mmap framebuffer pages
 917  *
 918  * This function is used as the &fb_deferred_io.deferred_io
 919  * callback function for flushing the fbdev mmap writes.
 920  */
 921 void drm_fb_helper_deferred_io(struct fb_info *info,
 922                                struct list_head *pagelist)
 923 {
 924         unsigned long start, end, min, max;
 925         struct page *page;
 926         u32 y1, y2;
 927
 928         min = ULONG_MAX;
 929         max = 0;
 930         list_for_each_entry(page, pagelist, lru) {
 931                 start = page->index << PAGE_SHIFT;
 932                 end = start + PAGE_SIZE - 1;
 933                 min = min(min, start);
 934                 max = max(max, end);
 935         }
 936
 937         if (min < max) {
 938                 y1 = min / info->fix.line_length;
 939                 y2 = min_t(u32, DIV_ROUND_UP(max, info->fix.line_length),
 940                            info->var.yres);
 941                 drm_fb_helper_dirty(info, 0, y1, info->var.xres, y2 - y1);
 942         }
 943 }
 944 EXPORT_SYMBOL(drm_fb_helper_deferred_io);
 945
 946 /**
 947  * drm_fb_helper_sys_read - wrapper around fb_sys_read
 948  * @info: fb_info struct pointer
 949  * @buf: userspace buffer to read from framebuffer memory
 950  * @count: number of bytes to read from framebuffer memory
 951  * @ppos: read offset within framebuffer memory
 952  *
 953  * A wrapper around fb_sys_read implemented by fbdev core
 954  */
 955 ssize_t drm_fb_helper_sys_read(struct fb_info *info, char __user *buf,
 956                                size_t count, loff_t *ppos)
 957 {
 958         return fb_sys_read(info, buf, count, ppos);
 959 }
 960 EXPORT_SYMBOL(drm_fb_helper_sys_read);
 961
 962 /**
 963  * drm_fb_helper_sys_write - wrapper around fb_sys_write
 964  * @info: fb_info struct pointer
 965  * @buf: userspace buffer to write to framebuffer memory
 966  * @count: number of bytes to write to framebuffer memory
 967  * @ppos: write offset within framebuffer memory
 968  *
 969  * A wrapper around fb_sys_write implemented by fbdev core
 970  */
 971 ssize_t drm_fb_helper_sys_write(struct fb_info *info, const char __user *buf,
 972                                 size_t count, loff_t *ppos)
 973 {
 974         ssize_t ret;
 975
 976         ret = fb_sys_write(info, buf, count, ppos);
 977         if (ret > 0)
 978                 drm_fb_helper_dirty(info, 0, 0, info->var.xres,
 979                                     info->var.yres);
 980
 981         return ret;
 982 }
 983 EXPORT_SYMBOL(drm_fb_helper_sys_write);
 984
 985 /**
 986  * drm_fb_helper_sys_fillrect - wrapper around sys_fillrect
 987  * @info: fbdev registered by the helper
 988  * @rect: info about rectangle to fill
 989  *
 990  * A wrapper around sys_fillrect implemented by fbdev core
 991  */
 992 void drm_fb_helper_sys_fillrect(struct fb_info *info,
 993                                 const struct fb_fillrect *rect)
 994 {
 995         sys_fillrect(info, rect);
 996         drm_fb_helper_dirty(info, rect->dx, rect->dy,
 997                             rect->width, rect->height);
 998 }
 999 EXPORT_SYMBOL(drm_fb_helper_sys_fillrect);
1000
1001 /**
1002  * drm_fb_helper_sys_copyarea - wrapper around sys_copyarea
1003  * @info: fbdev registered by the helper
1004  * @area: info about area to copy
1005  *
1006  * A wrapper around sys_copyarea implemented by fbdev core
1007  */
1008 void drm_fb_helper_sys_copyarea(struct fb_info *info,
1009                                 const struct fb_copyarea *area)
1010 {
1011         sys_copyarea(info, area);
1012         drm_fb_helper_dirty(info, area->dx, area->dy,
1013                             area->width, area->height);
1014 }
1015 EXPORT_SYMBOL(drm_fb_helper_sys_copyarea);
1016
1017 /**
1018  * drm_fb_helper_sys_imageblit - wrapper around sys_imageblit
1019  * @info: fbdev registered by the helper
1020  * @image: info about image to blit
1021  *
1022  * A wrapper around sys_imageblit implemented by fbdev core
1023  */
1024 void drm_fb_helper_sys_imageblit(struct fb_info *info,
1025                                  const struct fb_image *image)
1026 {
1027         sys_imageblit(info, image);
1028         drm_fb_helper_dirty(info, image->dx, image->dy,
1029                             image->width, image->height);
1030 }
1031 EXPORT_SYMBOL(drm_fb_helper_sys_imageblit);
1032
1033 /**
1034  * drm_fb_helper_cfb_fillrect - wrapper around cfb_fillrect
1035  * @info: fbdev registered by the helper
1036  * @rect: info about rectangle to fill
1037  *
1038  * A wrapper around cfb_imageblit implemented by fbdev core
1039  */
1040 void drm_fb_helper_cfb_fillrect(struct fb_info *info,
1041                                 const struct fb_fillrect *rect)
1042 {
1043         cfb_fillrect(info, rect);
1044         drm_fb_helper_dirty(info, rect->dx, rect->dy,
1045                             rect->width, rect->height);
1046 }
1047 EXPORT_SYMBOL(drm_fb_helper_cfb_fillrect);
1048
1049 /**
1050  * drm_fb_helper_cfb_copyarea - wrapper around cfb_copyarea
1051  * @info: fbdev registered by the helper
1052  * @area: info about area to copy
1053  *
1054  * A wrapper around cfb_copyarea implemented by fbdev core
1055  */
1056 void drm_fb_helper_cfb_copyarea(struct fb_info *info,
1057                                 const struct fb_copyarea *area)
1058 {
1059         cfb_copyarea(info, area);
1060         drm_fb_helper_dirty(info, area->dx, area->dy,
1061                             area->width, area->height);
1062 }
1063 EXPORT_SYMBOL(drm_fb_helper_cfb_copyarea);
1064
1065 /**
1066  * drm_fb_helper_cfb_imageblit - wrapper around cfb_imageblit
1067  * @info: fbdev registered by the helper
1068  * @image: info about image to blit
1069  *
1070  * A wrapper around cfb_imageblit implemented by fbdev core
1071  */
1072 void drm_fb_helper_cfb_imageblit(struct fb_info *info,
1073                                  const struct fb_image *image)
1074 {
1075         cfb_imageblit(info, image);
1076         drm_fb_helper_dirty(info, image->dx, image->dy,
1077                             image->width, image->height);
1078 }
1079 EXPORT_SYMBOL(drm_fb_helper_cfb_imageblit);
1080
1081 /**
1082  * drm_fb_helper_set_suspend - wrapper around fb_set_suspend
1083  * @fb_helper: driver-allocated fbdev helper
1084  * @suspend: whether to suspend or resume
1085  *
1086  * A wrapper around fb_set_suspend implemented by fbdev core.
1087  * Use drm_fb_helper_set_suspend_unlocked() if you don't need to take
1088  * the lock yourself
1089  */
1090 void drm_fb_helper_set_suspend(struct drm_fb_helper *fb_helper, bool suspend)
1091 {
1092         if (fb_helper && fb_helper->fbdev)
1093                 fb_set_suspend(fb_helper->fbdev, suspend);
1094 }
1095 EXPORT_SYMBOL(drm_fb_helper_set_suspend);
1096
1097 /**
1098  * drm_fb_helper_set_suspend_unlocked - wrapper around fb_set_suspend that also
1099  *                                      takes the console lock
1100  * @fb_helper: driver-allocated fbdev helper
1101  * @suspend: whether to suspend or resume
1102  *
1103  * A wrapper around fb_set_suspend() that takes the console lock. If the lock
1104  * isn't available on resume, a worker is tasked with waiting for the lock
1105  * to become available. The console lock can be pretty contented on resume
1106  * due to all the printk activity.
1107  *
1108  * This function can be called multiple times with the same state since
1109  * &fb_info.state is checked to see if fbdev is running or not before locking.
1110  *
1111  * Use drm_fb_helper_set_suspend() if you need to take the lock yourself.
1112  */
1113 void drm_fb_helper_set_suspend_unlocked(struct drm_fb_helper *fb_helper,
1114                                         bool suspend)
1115 {
1116         if (!fb_helper || !fb_helper->fbdev)
1117                 return;
1118
1119         /* make sure there's no pending/ongoing resume */
1120         flush_work(&fb_helper->resume_work);
1121
1122         if (suspend) {
1123                 if (fb_helper->fbdev->state != FBINFO_STATE_RUNNING)
1124                         return;
1125
1126                 console_lock();
1127
1128         } else {
1129                 if (fb_helper->fbdev->state == FBINFO_STATE_RUNNING)
1130                         return;
1131
1132                 if (!console_trylock()) {
1133                         schedule_work(&fb_helper->resume_work);
1134                         return;
1135                 }
1136         }
1137
1138         fb_set_suspend(fb_helper->fbdev, suspend);
1139         console_unlock();
1140 }
1141 EXPORT_SYMBOL(drm_fb_helper_set_suspend_unlocked);
1142
1143 static int setcolreg(struct drm_crtc *crtc, u16 red, u16 green,
1144                      u16 blue, u16 regno, struct fb_info *info)
1145 {
1146         struct drm_fb_helper *fb_helper = info->par;
1147         struct drm_framebuffer *fb = fb_helper->fb;
1148
1149         if (info->fix.visual == FB_VISUAL_TRUECOLOR) {
1150                 u32 *palette;
1151                 u32 value;
1152                 /* place color in psuedopalette */
1153                 if (regno > 16)
1154                         return -EINVAL;
1155                 palette = (u32 *)info->pseudo_palette;
1156                 red >>= (16 - info->var.red.length);
1157                 green >>= (16 - info->var.green.length);
1158                 blue >>= (16 - info->var.blue.length);
1159                 value = (red << info->var.red.offset) |
1160                         (green << info->var.green.offset) |
1161                         (blue << info->var.blue.offset);
1162                 if (info->var.transp.length > 0) {
1163                         u32 mask = (1 << info->var.transp.length) - 1;
1164                         mask <<= info->var.transp.offset;
1165                         value |= mask;
1166                 }
1167                 palette[regno] = value;
1168                 return 0;
1169         }
1170
1171         /*
1172          * The driver really shouldn't advertise pseudo/directcolor
1173          * visuals if it can't deal with the palette.
1174          */
1175         if (WARN_ON(!fb_helper->funcs->gamma_set ||
1176                     !fb_helper->funcs->gamma_get))
1177                 return -EINVAL;
1178
1179         WARN_ON(fb->format->cpp[0] != 1);
1180
1181         fb_helper->funcs->gamma_set(crtc, red, green, blue, regno);
1182
1183         return 0;
1184 }
1185
1186 /**
1187  * drm_fb_helper_setcmap - implementation for &fb_ops.fb_setcmap
1188  * @cmap: cmap to set
1189  * @info: fbdev registered by the helper
1190  */
1191 int drm_fb_helper_setcmap(struct fb_cmap *cmap, struct fb_info *info)
1192 {
1193         struct drm_fb_helper *fb_helper = info->par;
1194         struct drm_device *dev = fb_helper->dev;
1195         const struct drm_crtc_helper_funcs *crtc_funcs;
1196         u16 *red, *green, *blue, *transp;
1197         struct drm_crtc *crtc;
1198         int i, j, rc = 0;
1199         int start;
1200
1201         if (oops_in_progress)
1202                 return -EBUSY;
1203
1204         drm_modeset_lock_all(dev);
1205         if (!drm_fb_helper_is_bound(fb_helper)) {
1206                 drm_modeset_unlock_all(dev);
1207                 return -EBUSY;
1208         }
1209
1210         for (i = 0; i < fb_helper->crtc_count; i++) {
1211                 crtc = fb_helper->crtc_info[i].mode_set.crtc;
1212                 crtc_funcs = crtc->helper_private;
1213
1214                 red = cmap->red;
1215                 green = cmap->green;
1216                 blue = cmap->blue;
1217                 transp = cmap->transp;
1218                 start = cmap->start;
1219
1220                 for (j = 0; j < cmap->len; j++) {
1221                         u16 hred, hgreen, hblue, htransp = 0xffff;
1222
1223                         hred = *red++;
1224                         hgreen = *green++;
1225                         hblue = *blue++;
1226
1227                         if (transp)
1228                                 htransp = *transp++;
1229
1230                         rc = setcolreg(crtc, hred, hgreen, hblue, start++, info);
1231                         if (rc)
1232                                 goto out;
1233                 }
1234                 if (crtc_funcs->load_lut)
1235                         crtc_funcs->load_lut(crtc);
1236         }
1237  out:
1238         drm_modeset_unlock_all(dev);
1239         return rc;
1240 }
1241 EXPORT_SYMBOL(drm_fb_helper_setcmap);
1242
1243 /**
1244  * drm_fb_helper_check_var - implementation for &fb_ops.fb_check_var
1245  * @var: screeninfo to check
1246  * @info: fbdev registered by the helper
1247  */
1248 int drm_fb_helper_check_var(struct fb_var_screeninfo *var,
1249                             struct fb_info *info)
1250 {
1251         struct drm_fb_helper *fb_helper = info->par;
1252         struct drm_framebuffer *fb = fb_helper->fb;
1253         int depth;
1254
1255         if (var->pixclock != 0 || in_dbg_master())
1256                 return -EINVAL;
1257
1258         /*
1259          * Changes struct fb_var_screeninfo are currently not pushed back
1260          * to KMS, hence fail if different settings are requested.
1261          */
1262         if (var->bits_per_pixel != fb->format->cpp[0] * 8 ||
1263             var->xres > fb->width || var->yres > fb->height ||
1264             var->xres_virtual > fb->width || var->yres_virtual > fb->height) {
1265                 DRM_DEBUG("fb requested width/height/bpp can't fit in current fb "
1266                           "request %dx%d-%d (virtual %dx%d) > %dx%d-%d\n",
1267                           var->xres, var->yres, var->bits_per_pixel,
1268                           var->xres_virtual, var->yres_virtual,
1269                           fb->width, fb->height, fb->format->cpp[0] * 8);
1270                 return -EINVAL;
1271         }
1272
1273         switch (var->bits_per_pixel) {
1274         case 16:
1275                 depth = (var->green.length == 6) ? 16 : 15;
1276                 break;
1277         case 32:
1278                 depth = (var->transp.length > 0) ? 32 : 24;
1279                 break;
1280         default:
1281                 depth = var->bits_per_pixel;
1282                 break;
1283         }
1284
1285         switch (depth) {
1286         case 8:
1287                 var->red.offset = 0;
1288                 var->green.offset = 0;
1289                 var->blue.offset = 0;
1290                 var->red.length = 8;
1291                 var->green.length = 8;
1292                 var->blue.length = 8;
1293                 var->transp.length = 0;
1294                 var->transp.offset = 0;
1295                 break;
1296         case 15:
1297                 var->red.offset = 10;
1298                 var->green.offset = 5;
1299                 var->blue.offset = 0;
1300                 var->red.length = 5;
1301                 var->green.length = 5;
1302                 var->blue.length = 5;
1303                 var->transp.length = 1;
1304                 var->transp.offset = 15;
1305                 break;
1306         case 16:
1307                 var->red.offset = 11;
1308                 var->green.offset = 5;
1309                 var->blue.offset = 0;
1310                 var->red.length = 5;
1311                 var->green.length = 6;
1312                 var->blue.length = 5;
1313                 var->transp.length = 0;
1314                 var->transp.offset = 0;
1315                 break;
1316         case 24:
1317                 var->red.offset = 16;
1318                 var->green.offset = 8;
1319                 var->blue.offset = 0;
1320                 var->red.length = 8;
1321                 var->green.length = 8;
1322                 var->blue.length = 8;
1323                 var->transp.length = 0;
1324                 var->transp.offset = 0;
1325                 break;
1326         case 32:
1327                 var->red.offset = 16;
1328                 var->green.offset = 8;
1329                 var->blue.offset = 0;
1330                 var->red.length = 8;
1331                 var->green.length = 8;
1332                 var->blue.length = 8;
1333                 var->transp.length = 8;
1334                 var->transp.offset = 24;
1335                 break;
1336         default:
1337                 return -EINVAL;
1338         }
1339         return 0;
1340 }
1341 EXPORT_SYMBOL(drm_fb_helper_check_var);
1342
1343 /**
1344  * drm_fb_helper_set_par - implementation for &fb_ops.fb_set_par
1345  * @info: fbdev registered by the helper
1346  *
1347  * This will let fbcon do the mode init and is called at initialization time by
1348  * the fbdev core when registering the driver, and later on through the hotplug
1349  * callback.
1350  */
1351 int drm_fb_helper_set_par(struct fb_info *info)
1352 {
1353         struct drm_fb_helper *fb_helper = info->par;
1354         struct fb_var_screeninfo *var = &info->var;
1355
1356         if (oops_in_progress)
1357                 return -EBUSY;
1358
1359         if (var->pixclock != 0) {
1360                 DRM_ERROR("PIXEL CLOCK SET\n");
1361                 return -EINVAL;
1362         }
1363
1364         drm_fb_helper_restore_fbdev_mode_unlocked(fb_helper);
1365
1366         return 0;
1367 }
1368 EXPORT_SYMBOL(drm_fb_helper_set_par);
1369
1370 static int pan_display_atomic(struct fb_var_screeninfo *var,
1371                               struct fb_info *info)
1372 {
1373         struct drm_fb_helper *fb_helper = info->par;
1374         struct drm_device *dev = fb_helper->dev;
1375         struct drm_atomic_state *state;
1376         struct drm_plane *plane;
1377         int i, ret;
1378         unsigned plane_mask;
1379
1380         state = drm_atomic_state_alloc(dev);
1381         if (!state)
1382                 return -ENOMEM;
1383
1384         state->acquire_ctx = dev->mode_config.acquire_ctx;
1385 retry:
1386         plane_mask = 0;
1387         for(i = 0; i < fb_helper->crtc_count; i++) {
1388                 struct drm_mode_set *mode_set;
1389
1390                 mode_set = &fb_helper->crtc_info[i].mode_set;
1391
1392                 mode_set->x = var->xoffset;
1393                 mode_set->y = var->yoffset;
1394
1395                 ret = __drm_atomic_helper_set_config(mode_set, state);
1396                 if (ret != 0)
1397                         goto fail;
1398
1399                 plane = mode_set->crtc->primary;
1400                 plane_mask |= (1 << drm_plane_index(plane));
1401                 plane->old_fb = plane->fb;
1402         }
1403
1404         ret = drm_atomic_commit(state);
1405         if (ret != 0)
1406                 goto fail;
1407
1408         info->var.xoffset = var->xoffset;
1409         info->var.yoffset = var->yoffset;
1410
1411 fail:
1412         drm_atomic_clean_old_fb(dev, plane_mask, ret);
1413
1414         if (ret == -EDEADLK)
1415                 goto backoff;
1416
1417         drm_atomic_state_put(state);
1418         return ret;
1419
1420 backoff:
1421         drm_atomic_state_clear(state);
1422         drm_atomic_legacy_backoff(state);
1423
1424         goto retry;
1425 }
1426
1427 /**
1428  * drm_fb_helper_pan_display - implementation for &fb_ops.fb_pan_display
1429  * @var: updated screen information
1430  * @info: fbdev registered by the helper
1431  */
1432 int drm_fb_helper_pan_display(struct fb_var_screeninfo *var,
1433                               struct fb_info *info)
1434 {
1435         struct drm_fb_helper *fb_helper = info->par;
1436         struct drm_device *dev = fb_helper->dev;
1437         struct drm_mode_set *modeset;
1438         int ret = 0;
1439         int i;
1440
1441         if (oops_in_progress)
1442                 return -EBUSY;
1443
1444         drm_modeset_lock_all(dev);
1445         if (!drm_fb_helper_is_bound(fb_helper)) {
1446                 drm_modeset_unlock_all(dev);
1447                 return -EBUSY;
1448         }
1449
1450         if (drm_drv_uses_atomic_modeset(dev)) {
1451                 ret = pan_display_atomic(var, info);
1452                 goto unlock;
1453         }
1454
1455         for (i = 0; i < fb_helper->crtc_count; i++) {
1456                 modeset = &fb_helper->crtc_info[i].mode_set;
1457
1458                 modeset->x = var->xoffset;
1459                 modeset->y = var->yoffset;
1460
1461                 if (modeset->num_connectors) {
1462                         ret = drm_mode_set_config_internal(modeset);
1463                         if (!ret) {
1464                                 info->var.xoffset = var->xoffset;
1465                                 info->var.yoffset = var->yoffset;
1466                         }
1467                 }
1468         }
1469 unlock:
1470         drm_modeset_unlock_all(dev);
1471         return ret;
1472 }
1473 EXPORT_SYMBOL(drm_fb_helper_pan_display);
1474
1475 /*
1476  * Allocates the backing storage and sets up the fbdev info structure through
1477  * the ->fb_probe callback and then registers the fbdev and sets up the panic
1478  * notifier.
1479  */
1480 static int drm_fb_helper_single_fb_probe(struct drm_fb_helper *fb_helper,
1481                                          int preferred_bpp)
1482 {
1483         int ret = 0;
1484         int crtc_count = 0;
1485         int i;
1486         struct drm_fb_helper_surface_size sizes;
1487         int gamma_size = 0;
1488
1489         memset(&sizes, 0, sizeof(struct drm_fb_helper_surface_size));
1490         sizes.surface_depth = 24;
1491         sizes.surface_bpp = 32;
1492         sizes.fb_width = (unsigned)-1;
1493         sizes.fb_height = (unsigned)-1;
1494
1495         /* if driver picks 8 or 16 by default use that
1496            for both depth/bpp */
1497         if (preferred_bpp != sizes.surface_bpp)
1498                 sizes.surface_depth = sizes.surface_bpp = preferred_bpp;
1499
1500         /* first up get a count of crtcs now in use and new min/maxes width/heights */
1501         drm_fb_helper_for_each_connector(fb_helper, i) {
1502                 struct drm_fb_helper_connector *fb_helper_conn = fb_helper->connector_info[i];
1503                 struct drm_cmdline_mode *cmdline_mode;
1504
1505                 cmdline_mode = &fb_helper_conn->connector->cmdline_mode;
1506
1507                 if (cmdline_mode->bpp_specified) {
1508                         switch (cmdline_mode->bpp) {
1509                         case 8:
1510                                 sizes.surface_depth = sizes.surface_bpp = 8;
1511                                 break;
1512                         case 15:
1513                                 sizes.surface_depth = 15;
1514                                 sizes.surface_bpp = 16;
1515                                 break;
1516                         case 16:
1517                                 sizes.surface_depth = sizes.surface_bpp = 16;
1518                                 break;
1519                         case 24:
1520                                 sizes.surface_depth = sizes.surface_bpp = 24;
1521                                 break;
1522                         case 32:
1523                                 sizes.surface_depth = 24;
1524                                 sizes.surface_bpp = 32;
1525                                 break;
1526                         }
1527                         break;
1528                 }
1529         }
1530
1531         crtc_count = 0;
1532         for (i = 0; i < fb_helper->crtc_count; i++) {
1533                 struct drm_display_mode *desired_mode;
1534                 struct drm_mode_set *mode_set;
1535                 int x, y, j;
1536                 /* in case of tile group, are we the last tile vert or horiz?
1537                  * If no tile group you are always the last one both vertically
1538                  * and horizontally
1539                  */
1540                 bool lastv = true, lasth = true;
1541
1542                 desired_mode = fb_helper->crtc_info[i].desired_mode;
1543                 mode_set = &fb_helper->crtc_info[i].mode_set;
1544
1545                 if (!desired_mode)
1546                         continue;
1547
1548                 crtc_count++;
1549
1550                 x = fb_helper->crtc_info[i].x;
1551                 y = fb_helper->crtc_info[i].y;
1552
1553                 if (gamma_size == 0)
1554                         gamma_size = fb_helper->crtc_info[i].mode_set.crtc->gamma_size;
1555
1556                 sizes.surface_width  = max_t(u32, desired_mode->hdisplay + x, sizes.surface_width);
1557                 sizes.surface_height = max_t(u32, desired_mode->vdisplay + y, sizes.surface_height);
1558
1559                 for (j = 0; j < mode_set->num_connectors; j++) {
1560                         struct drm_connector *connector = mode_set->connectors[j];
1561                         if (connector->has_tile) {
1562                                 lasth = (connector->tile_h_loc == (connector->num_h_tile - 1));
1563                                 lastv = (connector->tile_v_loc == (connector->num_v_tile - 1));
1564                                 /* cloning to multiple tiles is just crazy-talk, so: */
1565                                 break;
1566                         }
1567                 }
1568
1569                 if (lasth)
1570                         sizes.fb_width  = min_t(u32, desired_mode->hdisplay + x, sizes.fb_width);
1571                 if (lastv)
1572                         sizes.fb_height = min_t(u32, desired_mode->vdisplay + y, sizes.fb_height);
1573         }
1574
1575         if (crtc_count == 0 || sizes.fb_width == -1 || sizes.fb_height == -1) {
1576                 /* hmm everyone went away - assume VGA cable just fell out
1577                    and will come back later. */
1578                 DRM_INFO("Cannot find any crtc or sizes - going 1024x768\n");
1579                 sizes.fb_width = sizes.surface_width = 1024;
1580                 sizes.fb_height = sizes.surface_height = 768;
1581         }
1582
1583         /* push down into drivers */
1584         ret = (*fb_helper->funcs->fb_probe)(fb_helper, &sizes);
1585         if (ret < 0)
1586                 return ret;
1587
1588         /*
1589          * Set the fb pointer - usually drm_setup_crtcs does this for hotplug
1590          * events, but at init time drm_setup_crtcs needs to be called before
1591          * the fb is allocated (since we need to figure out the desired size of
1592          * the fb before we can allocate it ...). Hence we need to fix things up
1593          * here again.
1594          */
1595         for (i = 0; i < fb_helper->crtc_count; i++)
1596                 if (fb_helper->crtc_info[i].mode_set.num_connectors)
1597                         fb_helper->crtc_info[i].mode_set.fb = fb_helper->fb;
1598
1599         return 0;
1600 }
1601
1602 /**
1603  * drm_fb_helper_fill_fix - initializes fixed fbdev information
1604  * @info: fbdev registered by the helper
1605  * @pitch: desired pitch
1606  * @depth: desired depth
1607  *
1608  * Helper to fill in the fixed fbdev information useful for a non-accelerated
1609  * fbdev emulations. Drivers which support acceleration methods which impose
1610  * additional constraints need to set up their own limits.
1611  *
1612  * Drivers should call this (or their equivalent setup code) from their
1613  * &drm_fb_helper_funcs.fb_probe callback.
1614  */
1615 void drm_fb_helper_fill_fix(struct fb_info *info, uint32_t pitch,
1616                             uint32_t depth)
1617 {
1618         info->fix.type = FB_TYPE_PACKED_PIXELS;
1619         info->fix.visual = depth == 8 ? FB_VISUAL_PSEUDOCOLOR :
1620                 FB_VISUAL_TRUECOLOR;
1621         info->fix.mmio_start = 0;
1622         info->fix.mmio_len = 0;
1623         info->fix.type_aux = 0;
1624         info->fix.xpanstep = 1; /* doing it in hw */
1625         info->fix.ypanstep = 1; /* doing it in hw */
1626         info->fix.ywrapstep = 0;
1627         info->fix.accel = FB_ACCEL_NONE;
1628
1629         info->fix.line_length = pitch;
1630         return;
1631 }
1632 EXPORT_SYMBOL(drm_fb_helper_fill_fix);
1633
1634 /**
1635  * drm_fb_helper_fill_var - initalizes variable fbdev information
1636  * @info: fbdev instance to set up
1637  * @fb_helper: fb helper instance to use as template
1638  * @fb_width: desired fb width
1639  * @fb_height: desired fb height
1640  *
1641  * Sets up the variable fbdev metainformation from the given fb helper instance
1642  * and the drm framebuffer allocated in &drm_fb_helper.fb.
1643  *
1644  * Drivers should call this (or their equivalent setup code) from their
1645  * &drm_fb_helper_funcs.fb_probe callback after having allocated the fbdev
1646  * backing storage framebuffer.
1647  */
1648 void drm_fb_helper_fill_var(struct fb_info *info, struct drm_fb_helper *fb_helper,
1649                             uint32_t fb_width, uint32_t fb_height)
1650 {
1651         struct drm_framebuffer *fb = fb_helper->fb;
1652         info->pseudo_palette = fb_helper->pseudo_palette;
1653         info->var.xres_virtual = fb->width;
1654         info->var.yres_virtual = fb->height;
1655         info->var.bits_per_pixel = fb->format->cpp[0] * 8;
1656         info->var.accel_flags = FB_ACCELF_TEXT;
1657         info->var.xoffset = 0;
1658         info->var.yoffset = 0;
1659         info->var.activate = FB_ACTIVATE_NOW;
1660         info->var.height = -1;
1661         info->var.width = -1;
1662
1663         switch (fb->format->depth) {
1664         case 8:
1665                 info->var.red.offset = 0;
1666                 info->var.green.offset = 0;
1667                 info->var.blue.offset = 0;
1668                 info->var.red.length = 8; /* 8bit DAC */
1669                 info->var.green.length = 8;
1670                 info->var.blue.length = 8;
1671                 info->var.transp.offset = 0;
1672                 info->var.transp.length = 0;
1673                 break;
1674         case 15:
1675                 info->var.red.offset = 10;
1676                 info->var.green.offset = 5;
1677                 info->var.blue.offset = 0;
1678                 info->var.red.length = 5;
1679                 info->var.green.length = 5;
1680                 info->var.blue.length = 5;
1681                 info->var.transp.offset = 15;
1682                 info->var.transp.length = 1;
1683                 break;
1684         case 16:
1685                 info->var.red.offset = 11;
1686                 info->var.green.offset = 5;
1687                 info->var.blue.offset = 0;
1688                 info->var.red.length = 5;
1689                 info->var.green.length = 6;
1690                 info->var.blue.length = 5;
1691                 info->var.transp.offset = 0;
1692                 break;
1693         case 24:
1694                 info->var.red.offset = 16;
1695                 info->var.green.offset = 8;
1696                 info->var.blue.offset = 0;
1697                 info->var.red.length = 8;
1698                 info->var.green.length = 8;
1699                 info->var.blue.length = 8;
1700                 info->var.transp.offset = 0;
1701                 info->var.transp.length = 0;
1702                 break;
1703         case 32:
1704                 info->var.red.offset = 16;
1705                 info->var.green.offset = 8;
1706                 info->var.blue.offset = 0;
1707                 info->var.red.length = 8;
1708                 info->var.green.length = 8;
1709                 info->var.blue.length = 8;
1710                 info->var.transp.offset = 24;
1711                 info->var.transp.length = 8;
1712                 break;
1713         default:
1714                 break;
1715         }
1716
1717         info->var.xres = fb_width;
1718         info->var.yres = fb_height;
1719 }
1720 EXPORT_SYMBOL(drm_fb_helper_fill_var);
1721
1722 static int drm_fb_helper_probe_connector_modes(struct drm_fb_helper *fb_helper,
1723                                                uint32_t maxX,
1724                                                uint32_t maxY)
1725 {
1726         struct drm_connector *connector;
1727         int count = 0;
1728         int i;
1729
1730         drm_fb_helper_for_each_connector(fb_helper, i) {
1731                 connector = fb_helper->connector_info[i]->connector;
1732                 count += connector->funcs->fill_modes(connector, maxX, maxY);
1733         }
1734
1735         return count;
1736 }
1737
1738 struct drm_display_mode *drm_has_preferred_mode(struct drm_fb_helper_connector *fb_connector, int width, int height)
1739 {
1740         struct drm_display_mode *mode;
1741
1742         list_for_each_entry(mode, &fb_connector->connector->modes, head) {
1743                 if (mode->hdisplay > width ||
1744                     mode->vdisplay > height)
1745                         continue;
1746                 if (mode->type & DRM_MODE_TYPE_PREFERRED)
1747                         return mode;
1748         }
1749         return NULL;
1750 }
1751 EXPORT_SYMBOL(drm_has_preferred_mode);
1752
1753 static bool drm_has_cmdline_mode(struct drm_fb_helper_connector *fb_connector)
1754 {
1755         return fb_connector->connector->cmdline_mode.specified;
1756 }
1757
1758 struct drm_display_mode *drm_pick_cmdline_mode(struct drm_fb_helper_connector *fb_helper_conn)
1759 {
1760         struct drm_cmdline_mode *cmdline_mode;
1761         struct drm_display_mode *mode;
1762         bool prefer_non_interlace;
1763
1764         cmdline_mode = &fb_helper_conn->connector->cmdline_mode;
1765         if (cmdline_mode->specified == false)
1766                 return NULL;
1767
1768         /* attempt to find a matching mode in the list of modes
1769          *  we have gotten so far, if not add a CVT mode that conforms
1770          */
1771         if (cmdline_mode->rb || cmdline_mode->margins)
1772                 goto create_mode;
1773
1774         prefer_non_interlace = !cmdline_mode->interlace;
1775 again:
1776         list_for_each_entry(mode, &fb_helper_conn->connector->modes, head) {
1777                 /* check width/height */
1778                 if (mode->hdisplay != cmdline_mode->xres ||
1779                     mode->vdisplay != cmdline_mode->yres)
1780                         continue;
1781
1782                 if (cmdline_mode->refresh_specified) {
1783                         if (mode->vrefresh != cmdline_mode->refresh)
1784                                 continue;
1785                 }
1786
1787                 if (cmdline_mode->interlace) {
1788                         if (!(mode->flags & DRM_MODE_FLAG_INTERLACE))
1789                                 continue;
1790                 } else if (prefer_non_interlace) {
1791                         if (mode->flags & DRM_MODE_FLAG_INTERLACE)
1792                                 continue;
1793                 }
1794                 return mode;
1795         }
1796
1797         if (prefer_non_interlace) {
1798                 prefer_non_interlace = false;
1799                 goto again;
1800         }
1801
1802 create_mode:
1803         mode = drm_mode_create_from_cmdline_mode(fb_helper_conn->connector->dev,
1804                                                  cmdline_mode);
1805         list_add(&mode->head, &fb_helper_conn->connector->modes);
1806         return mode;
1807 }
1808 EXPORT_SYMBOL(drm_pick_cmdline_mode);
1809
1810 static bool drm_connector_enabled(struct drm_connector *connector, bool strict)
1811 {
1812         bool enable;
1813
1814         if (strict)
1815                 enable = connector->status == connector_status_connected;
1816         else
1817                 enable = connector->status != connector_status_disconnected;
1818
1819         return enable;
1820 }
1821
1822 static void drm_enable_connectors(struct drm_fb_helper *fb_helper,
1823                                   bool *enabled)
1824 {
1825         bool any_enabled = false;
1826         struct drm_connector *connector;
1827         int i = 0;
1828
1829         drm_fb_helper_for_each_connector(fb_helper, i) {
1830                 connector = fb_helper->connector_info[i]->connector;
1831                 enabled[i] = drm_connector_enabled(connector, true);
1832                 DRM_DEBUG_KMS("connector %d enabled? %s\n", connector->base.id,
1833                           enabled[i] ? "yes" : "no");
1834                 any_enabled |= enabled[i];
1835         }
1836
1837         if (any_enabled)
1838                 return;
1839
1840         drm_fb_helper_for_each_connector(fb_helper, i) {
1841                 connector = fb_helper->connector_info[i]->connector;
1842                 enabled[i] = drm_connector_enabled(connector, false);
1843         }
1844 }
1845
1846 static bool drm_target_cloned(struct drm_fb_helper *fb_helper,
1847                               struct drm_display_mode **modes,
1848                               struct drm_fb_offset *offsets,
1849                               bool *enabled, int width, int height)
1850 {
1851         int count, i, j;
1852         bool can_clone = false;
1853         struct drm_fb_helper_connector *fb_helper_conn;
1854         struct drm_display_mode *dmt_mode, *mode;
1855
1856         /* only contemplate cloning in the single crtc case */
1857         if (fb_helper->crtc_count > 1)
1858                 return false;
1859
1860         count = 0;
1861         drm_fb_helper_for_each_connector(fb_helper, i) {
1862                 if (enabled[i])
1863                         count++;
1864         }
1865
1866         /* only contemplate cloning if more than one connector is enabled */
1867         if (count <= 1)
1868                 return false;
1869
1870         /* check the command line or if nothing common pick 1024x768 */
1871         can_clone = true;
1872         drm_fb_helper_for_each_connector(fb_helper, i) {
1873                 if (!enabled[i])
1874                         continue;
1875                 fb_helper_conn = fb_helper->connector_info[i];
1876                 modes[i] = drm_pick_cmdline_mode(fb_helper_conn);
1877                 if (!modes[i]) {
1878                         can_clone = false;
1879                         break;
1880                 }
1881                 for (j = 0; j < i; j++) {
1882                         if (!enabled[j])
1883                                 continue;
1884                         if (!drm_mode_equal(modes[j], modes[i]))
1885                                 can_clone = false;
1886                 }
1887         }
1888
1889         if (can_clone) {
1890                 DRM_DEBUG_KMS("can clone using command line\n");
1891                 return true;
1892         }
1893
1894         /* try and find a 1024x768 mode on each connector */
1895         can_clone = true;
1896         dmt_mode = drm_mode_find_dmt(fb_helper->dev, 1024, 768, 60, false);
1897
1898         drm_fb_helper_for_each_connector(fb_helper, i) {
1899                 if (!enabled[i])
1900                         continue;
1901
1902                 fb_helper_conn = fb_helper->connector_info[i];
1903                 list_for_each_entry(mode, &fb_helper_conn->connector->modes, head) {
1904                         if (drm_mode_equal(mode, dmt_mode))
1905                                 modes[i] = mode;
1906                 }
1907                 if (!modes[i])
1908                         can_clone = false;
1909         }
1910
1911         if (can_clone) {
1912                 DRM_DEBUG_KMS("can clone using 1024x768\n");
1913                 return true;
1914         }
1915         DRM_INFO("kms: can't enable cloning when we probably wanted to.\n");
1916         return false;
1917 }
1918
1919 static int drm_get_tile_offsets(struct drm_fb_helper *fb_helper,
1920                                 struct drm_display_mode **modes,
1921                                 struct drm_fb_offset *offsets,
1922                                 int idx,
1923                                 int h_idx, int v_idx)
1924 {
1925         struct drm_fb_helper_connector *fb_helper_conn;
1926         int i;
1927         int hoffset = 0, voffset = 0;
1928
1929         drm_fb_helper_for_each_connector(fb_helper, i) {
1930                 fb_helper_conn = fb_helper->connector_info[i];
1931                 if (!fb_helper_conn->connector->has_tile)
1932                         continue;
1933
1934                 if (!modes[i] && (h_idx || v_idx)) {
1935                         DRM_DEBUG_KMS("no modes for connector tiled %d %d\n", i,
1936                                       fb_helper_conn->connector->base.id);
1937                         continue;
1938                 }
1939                 if (fb_helper_conn->connector->tile_h_loc < h_idx)
1940                         hoffset += modes[i]->hdisplay;
1941
1942                 if (fb_helper_conn->connector->tile_v_loc < v_idx)
1943                         voffset += modes[i]->vdisplay;
1944         }
1945         offsets[idx].x = hoffset;
1946         offsets[idx].y = voffset;
1947         DRM_DEBUG_KMS("returned %d %d for %d %d\n", hoffset, voffset, h_idx, v_idx);
1948         return 0;
1949 }
1950
1951 static bool drm_target_preferred(struct drm_fb_helper *fb_helper,
1952                                  struct drm_display_mode **modes,
1953                                  struct drm_fb_offset *offsets,
1954                                  bool *enabled, int width, int height)
1955 {
1956         struct drm_fb_helper_connector *fb_helper_conn;
1957         const u64 mask = BIT_ULL(fb_helper->connector_count) - 1;
1958         u64 conn_configured = 0;
1959         int tile_pass = 0;
1960         int i;
1961
1962 retry:
1963         drm_fb_helper_for_each_connector(fb_helper, i) {
1964                 fb_helper_conn = fb_helper->connector_info[i];
1965
1966                 if (conn_configured & BIT_ULL(i))
1967                         continue;
1968
1969                 if (enabled[i] == false) {
1970                         conn_configured |= BIT_ULL(i);
1971                         continue;
1972                 }
1973
1974                 /* first pass over all the untiled connectors */
1975                 if (tile_pass == 0 && fb_helper_conn->connector->has_tile)
1976                         continue;
1977
1978                 if (tile_pass == 1) {
1979                         if (fb_helper_conn->connector->tile_h_loc != 0 ||
1980                             fb_helper_conn->connector->tile_v_loc != 0)
1981                                 continue;
1982
1983                 } else {
1984                         if (fb_helper_conn->connector->tile_h_loc != tile_pass -1 &&
1985                             fb_helper_conn->connector->tile_v_loc != tile_pass - 1)
1986                         /* if this tile_pass doesn't cover any of the tiles - keep going */
1987                                 continue;
1988
1989                         /* find the tile offsets for this pass - need
1990                            to find all tiles left and above */
1991                         drm_get_tile_offsets(fb_helper, modes, offsets,
1992                                              i, fb_helper_conn->connector->tile_h_loc, fb_helper_conn->connector->tile_v_loc);
1993                 }
1994                 DRM_DEBUG_KMS("looking for cmdline mode on connector %d\n",
1995                               fb_helper_conn->connector->base.id);
1996
1997                 /* got for command line mode first */
1998                 modes[i] = drm_pick_cmdline_mode(fb_helper_conn);
1999                 if (!modes[i]) {
2000                         DRM_DEBUG_KMS("looking for preferred mode on connector %d %d\n",
2001                                       fb_helper_conn->connector->base.id, fb_helper_conn->connector->tile_group ? fb_helper_conn->connector->tile_group->id : 0);
2002                         modes[i] = drm_has_preferred_mode(fb_helper_conn, width, height);
2003                 }
2004                 /* No preferred modes, pick one off the list */
2005                 if (!modes[i] && !list_empty(&fb_helper_conn->connector->modes)) {
2006                         list_for_each_entry(modes[i], &fb_helper_conn->connector->modes, head)
2007                                 break;
2008                 }
2009                 DRM_DEBUG_KMS("found mode %s\n", modes[i] ? modes[i]->name :
2010                           "none");
2011                 conn_configured |= BIT_ULL(i);
2012         }
2013
2014         if ((conn_configured & mask) != mask) {
2015                 tile_pass++;
2016                 goto retry;
2017         }
2018         return true;
2019 }
2020
2021 static int drm_pick_crtcs(struct drm_fb_helper *fb_helper,
2022                           struct drm_fb_helper_crtc **best_crtcs,
2023                           struct drm_display_mode **modes,
2024                           int n, int width, int height)
2025 {
2026         int c, o;
2027         struct drm_connector *connector;
2028         const struct drm_connector_helper_funcs *connector_funcs;
2029         struct drm_encoder *encoder;
2030         int my_score, best_score, score;
2031         struct drm_fb_helper_crtc **crtcs, *crtc;
2032         struct drm_fb_helper_connector *fb_helper_conn;
2033
2034         if (n == fb_helper->connector_count)
2035                 return 0;
2036
2037         fb_helper_conn = fb_helper->connector_info[n];
2038         connector = fb_helper_conn->connector;
2039
2040         best_crtcs[n] = NULL;
2041         best_score = drm_pick_crtcs(fb_helper, best_crtcs, modes, n+1, width, height);
2042         if (modes[n] == NULL)
2043                 return best_score;
2044
2045         crtcs = kzalloc(fb_helper->connector_count *
2046                         sizeof(struct drm_fb_helper_crtc *), GFP_KERNEL);
2047         if (!crtcs)
2048                 return best_score;
2049
2050         my_score = 1;
2051         if (connector->status == connector_status_connected)
2052                 my_score++;
2053         if (drm_has_cmdline_mode(fb_helper_conn))
2054                 my_score++;
2055         if (drm_has_preferred_mode(fb_helper_conn, width, height))
2056                 my_score++;
2057
2058         connector_funcs = connector->helper_private;
2059
2060         /*
2061          * If the DRM device implements atomic hooks and ->best_encoder() is
2062          * NULL we fallback to the default drm_atomic_helper_best_encoder()
2063          * helper.
2064          */
2065         if (drm_drv_uses_atomic_modeset(fb_helper->dev) &&
2066             !connector_funcs->best_encoder)
2067                 encoder = drm_atomic_helper_best_encoder(connector);
2068         else
2069                 encoder = connector_funcs->best_encoder(connector);
2070
2071         if (!encoder)
2072                 goto out;
2073
2074         /* select a crtc for this connector and then attempt to configure
2075            remaining connectors */
2076         for (c = 0; c < fb_helper->crtc_count; c++) {
2077                 crtc = &fb_helper->crtc_info[c];
2078
2079                 if ((encoder->possible_crtcs & (1 << c)) == 0)
2080                         continue;
2081
2082                 for (o = 0; o < n; o++)
2083                         if (best_crtcs[o] == crtc)
2084                                 break;
2085
2086                 if (o < n) {
2087                         /* ignore cloning unless only a single crtc */
2088                         if (fb_helper->crtc_count > 1)
2089                                 continue;
2090
2091                         if (!drm_mode_equal(modes[o], modes[n]))
2092                                 continue;
2093                 }
2094
2095                 crtcs[n] = crtc;
2096                 memcpy(crtcs, best_crtcs, n * sizeof(struct drm_fb_helper_crtc *));
2097                 score = my_score + drm_pick_crtcs(fb_helper, crtcs, modes, n + 1,
2098                                                   width, height);
2099                 if (score > best_score) {
2100                         best_score = score;
2101                         memcpy(best_crtcs, crtcs,
2102                                fb_helper->connector_count *
2103                                sizeof(struct drm_fb_helper_crtc *));
2104                 }
2105         }
2106 out:
2107         kfree(crtcs);
2108         return best_score;
2109 }
2110
2111 static void drm_setup_crtcs(struct drm_fb_helper *fb_helper,
2112                             u32 width, u32 height)
2113 {
2114         struct drm_device *dev = fb_helper->dev;
2115         struct drm_fb_helper_crtc **crtcs;
2116         struct drm_display_mode **modes;
2117         struct drm_fb_offset *offsets;
2118         bool *enabled;
2119         int i;
2120
2121         DRM_DEBUG_KMS("\n");
2122         if (drm_fb_helper_probe_connector_modes(fb_helper, width, height) == 0)
2123                 DRM_DEBUG_KMS("No connectors reported connected with modes\n");
2124
2125         /* prevent concurrent modification of connector_count by hotplug */
2126         lockdep_assert_held(&fb_helper->dev->mode_config.mutex);
2127
2128         crtcs = kcalloc(fb_helper->connector_count,
2129                         sizeof(struct drm_fb_helper_crtc *), GFP_KERNEL);
2130         modes = kcalloc(fb_helper->connector_count,
2131                         sizeof(struct drm_display_mode *), GFP_KERNEL);
2132         offsets = kcalloc(fb_helper->connector_count,
2133                           sizeof(struct drm_fb_offset), GFP_KERNEL);
2134         enabled = kcalloc(fb_helper->connector_count,
2135                           sizeof(bool), GFP_KERNEL);
2136         if (!crtcs || !modes || !enabled || !offsets) {
2137                 DRM_ERROR("Memory allocation failed\n");
2138                 goto out;
2139         }
2140
2141         drm_enable_connectors(fb_helper, enabled);
2142
2143         if (!(fb_helper->funcs->initial_config &&
2144               fb_helper->funcs->initial_config(fb_helper, crtcs, modes,
2145                                                offsets,
2146                                                enabled, width, height))) {
2147                 memset(modes, 0, fb_helper->connector_count*sizeof(modes[0]));
2148                 memset(crtcs, 0, fb_helper->connector_count*sizeof(crtcs[0]));
2149                 memset(offsets, 0, fb_helper->connector_count*sizeof(offsets[0]));
2150
2151                 if (!drm_target_cloned(fb_helper, modes, offsets,
2152                                        enabled, width, height) &&
2153                     !drm_target_preferred(fb_helper, modes, offsets,
2154                                           enabled, width, height))
2155                         DRM_ERROR("Unable to find initial modes\n");
2156
2157                 DRM_DEBUG_KMS("picking CRTCs for %dx%d config\n",
2158                               width, height);
2159
2160                 drm_pick_crtcs(fb_helper, crtcs, modes, 0, width, height);
2161         }
2162
2163         /* need to set the modesets up here for use later */
2164         /* fill out the connector<->crtc mappings into the modesets */
2165         for (i = 0; i < fb_helper->crtc_count; i++)
2166                 drm_fb_helper_modeset_release(fb_helper,
2167                                               &fb_helper->crtc_info[i].mode_set);
2168
2169         drm_fb_helper_for_each_connector(fb_helper, i) {
2170                 struct drm_display_mode *mode = modes[i];
2171                 struct drm_fb_helper_crtc *fb_crtc = crtcs[i];
2172                 struct drm_fb_offset *offset = &offsets[i];
2173                 struct drm_mode_set *modeset = &fb_crtc->mode_set;
2174
2175                 if (mode && fb_crtc) {
2176                         struct drm_connector *connector =
2177                                 fb_helper->connector_info[i]->connector;
2178
2179                         DRM_DEBUG_KMS("desired mode %s set on crtc %d (%d,%d)\n",
2180                                       mode->name, fb_crtc->mode_set.crtc->base.id, offset->x, offset->y);
2181
2182                         fb_crtc->desired_mode = mode;
2183                         fb_crtc->x = offset->x;
2184                         fb_crtc->y = offset->y;
2185                         modeset->mode = drm_mode_duplicate(dev,
2186                                                            fb_crtc->desired_mode);
2187                         drm_connector_reference(connector);
2188                         modeset->connectors[modeset->num_connectors++] = connector;
2189                         modeset->fb = fb_helper->fb;
2190                         modeset->x = offset->x;
2191                         modeset->y = offset->y;
2192                 }
2193         }
2194 out:
2195         kfree(crtcs);
2196         kfree(modes);
2197         kfree(offsets);
2198         kfree(enabled);
2199 }
2200
2201 /**
2202  * drm_fb_helper_initial_config - setup a sane initial connector configuration
2203  * @fb_helper: fb_helper device struct
2204  * @bpp_sel: bpp value to use for the framebuffer configuration
2205  *
2206  * Scans the CRTCs and connectors and tries to put together an initial setup.
2207  * At the moment, this is a cloned configuration across all heads with
2208  * a new framebuffer object as the backing store.
2209  *
2210  * Note that this also registers the fbdev and so allows userspace to call into
2211  * the driver through the fbdev interfaces.
2212  *
2213  * This function will call down into the &drm_fb_helper_funcs.fb_probe callback
2214  * to let the driver allocate and initialize the fbdev info structure and the
2215  * drm framebuffer used to back the fbdev. drm_fb_helper_fill_var() and
2216  * drm_fb_helper_fill_fix() are provided as helpers to setup simple default
2217  * values for the fbdev info structure.
2218  *
2219  * HANG DEBUGGING:
2220  *
2221  * When you have fbcon support built-in or already loaded, this function will do
2222  * a full modeset to setup the fbdev console. Due to locking misdesign in the
2223  * VT/fbdev subsystem that entire modeset sequence has to be done while holding
2224  * console_lock. Until console_unlock is called no dmesg lines will be sent out
2225  * to consoles, not even serial console. This means when your driver crashes,
2226  * you will see absolutely nothing else but a system stuck in this function,
2227  * with no further output. Any kind of printk() you place within your own driver
2228  * or in the drm core modeset code will also never show up.
2229  *
2230  * Standard debug practice is to run the fbcon setup without taking the
2231  * console_lock as a hack, to be able to see backtraces and crashes on the
2232  * serial line. This can be done by setting the fb.lockless_register_fb=1 kernel
2233  * cmdline option.
2234  *
2235  * The other option is to just disable fbdev emulation since very likely the
2236  * first modeset from userspace will crash in the same way, and is even easier
2237  * to debug. This can be done by setting the drm_kms_helper.fbdev_emulation=0
2238  * kernel cmdline option.
2239  *
2240  * RETURNS:
2241  * Zero if everything went ok, nonzero otherwise.
2242  */
2243 int drm_fb_helper_initial_config(struct drm_fb_helper *fb_helper, int bpp_sel)
2244 {
2245         struct drm_device *dev = fb_helper->dev;
2246         struct fb_info *info;
2247         int ret;
2248
2249         if (!drm_fbdev_emulation)
2250                 return 0;
2251
2252         mutex_lock(&dev->mode_config.mutex);
2253         drm_setup_crtcs(fb_helper,
2254                         dev->mode_config.max_width,
2255                         dev->mode_config.max_height);
2256         ret = drm_fb_helper_single_fb_probe(fb_helper, bpp_sel);
2257         mutex_unlock(&dev->mode_config.mutex);
2258         if (ret)
2259                 return ret;
2260
2261         info = fb_helper->fbdev;
2262         info->var.pixclock = 0;
2263         ret = register_framebuffer(info);
2264         if (ret < 0)
2265                 return ret;
2266
2267         dev_info(dev->dev, "fb%d: %s frame buffer device\n",
2268                  info->node, info->fix.id);
2269
2270         mutex_lock(&kernel_fb_helper_lock);
2271         if (list_empty(&kernel_fb_helper_list))
2272                 register_sysrq_key('v', &sysrq_drm_fb_helper_restore_op);
2273
2274         list_add(&fb_helper->kernel_fb_list, &kernel_fb_helper_list);
2275         mutex_unlock(&kernel_fb_helper_lock);
2276
2277         return 0;
2278 }
2279 EXPORT_SYMBOL(drm_fb_helper_initial_config);
2280
2281 /**
2282  * drm_fb_helper_hotplug_event - respond to a hotplug notification by
2283  *                               probing all the outputs attached to the fb
2284  * @fb_helper: the drm_fb_helper
2285  *
2286  * Scan the connectors attached to the fb_helper and try to put together a
2287  * setup after notification of a change in output configuration.
2288  *
2289  * Called at runtime, takes the mode config locks to be able to check/change the
2290  * modeset configuration. Must be run from process context (which usually means
2291  * either the output polling work or a work item launched from the driver's
2292  * hotplug interrupt).
2293  *
2294  * Note that drivers may call this even before calling
2295  * drm_fb_helper_initial_config but only after drm_fb_helper_init. This allows
2296  * for a race-free fbcon setup and will make sure that the fbdev emulation will
2297  * not miss any hotplug events.
2298  *
2299  * RETURNS:
2300  * 0 on success and a non-zero error code otherwise.
2301  */
2302 int drm_fb_helper_hotplug_event(struct drm_fb_helper *fb_helper)
2303 {
2304         struct drm_device *dev = fb_helper->dev;
2305
2306         if (!drm_fbdev_emulation)
2307                 return 0;
2308
2309         mutex_lock(&dev->mode_config.mutex);
2310         if (!fb_helper->fb || !drm_fb_helper_is_bound(fb_helper)) {
2311                 fb_helper->delayed_hotplug = true;
2312                 mutex_unlock(&dev->mode_config.mutex);
2313                 return 0;
2314         }
2315         DRM_DEBUG_KMS("\n");
2316
2317         drm_setup_crtcs(fb_helper, fb_helper->fb->width, fb_helper->fb->height);
2318
2319         mutex_unlock(&dev->mode_config.mutex);
2320
2321         drm_fb_helper_set_par(fb_helper->fbdev);
2322
2323         return 0;
2324 }
2325 EXPORT_SYMBOL(drm_fb_helper_hotplug_event);
2326
2327 /* The Kconfig DRM_KMS_HELPER selects FRAMEBUFFER_CONSOLE (if !EXPERT)
2328  * but the module doesn't depend on any fb console symbols.  At least
2329  * attempt to load fbcon to avoid leaving the system without a usable console.
2330  */
2331 int __init drm_fb_helper_modinit(void)
2332 {
2333 #if defined(CONFIG_FRAMEBUFFER_CONSOLE_MODULE) && !defined(CONFIG_EXPERT)
2334         const char *name = "fbcon";
2335         struct module *fbcon;
2336
2337         mutex_lock(&module_mutex);
2338         fbcon = find_module(name);
2339         mutex_unlock(&module_mutex);
2340
2341         if (!fbcon)
2342                 request_module_nowait(name);
2343 #endif
2344         return 0;
2345 }
2346 EXPORT_SYMBOL(drm_fb_helper_modinit);