root/drivers/gpu/drm/i915/display/intel_fbdev.c

DEFINITIONS

1. to_frontbuffer
2. intel_fbdev_invalidate
3. intel_fbdev_set_par
4. intel_fbdev_blank
5. intel_fbdev_pan_display
6. intelfb_alloc
7. intelfb_create
8. intel_fbdev_destroy
9. intel_fbdev_init_bios
10. intel_fbdev_suspend_worker
11. intel_fbdev_init
12. intel_fbdev_initial_config
13. intel_fbdev_initial_config_async
14. intel_fbdev_sync
15. intel_fbdev_unregister
16. intel_fbdev_fini
17. intel_fbdev_hpd_set_suspend
18. intel_fbdev_set_suspend
19. intel_fbdev_output_poll_changed
20. intel_fbdev_restore_mode

   1 /*
   2  * Copyright © 2007 David Airlie
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining a
   5  * copy of this software and associated documentation files (the "Software"),
   6  * to deal in the Software without restriction, including without limitation
   7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   8  * and/or sell copies of the Software, and to permit persons to whom the
   9  * Software is furnished to do so, subject to the following conditions:
  10  *
  11  * The above copyright notice and this permission notice (including the next
  12  * paragraph) shall be included in all copies or substantial portions of the
  13  * Software.
  14  *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  20  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  21  * DEALINGS IN THE SOFTWARE.
  22  *
  23  * Authors:
  24  *     David Airlie
  25  */
  26 
  27 #include <linux/async.h>
  28 #include <linux/console.h>
  29 #include <linux/delay.h>
  30 #include <linux/errno.h>
  31 #include <linux/init.h>
  32 #include <linux/kernel.h>
  33 #include <linux/mm.h>
  34 #include <linux/module.h>
  35 #include <linux/string.h>
  36 #include <linux/sysrq.h>
  37 #include <linux/tty.h>
  38 #include <linux/vga_switcheroo.h>
  39 
  40 #include <drm/drm_crtc.h>
  41 #include <drm/drm_fb_helper.h>
  42 #include <drm/drm_fourcc.h>
  43 #include <drm/i915_drm.h>
  44 
  45 #include "i915_drv.h"
  46 #include "intel_display_types.h"
  47 #include "intel_fbdev.h"
  48 #include "intel_frontbuffer.h"
  49 
  50 static struct intel_frontbuffer *to_frontbuffer(struct intel_fbdev *ifbdev)
  51 {
  52         return ifbdev->fb->frontbuffer;
  53 }
  54 
  55 static void intel_fbdev_invalidate(struct intel_fbdev *ifbdev)
  56 {
  57         intel_frontbuffer_invalidate(to_frontbuffer(ifbdev), ORIGIN_CPU);
  58 }
  59 
  60 static int intel_fbdev_set_par(struct fb_info *info)
  61 {
  62         struct drm_fb_helper *fb_helper = info->par;
  63         struct intel_fbdev *ifbdev =
  64                 container_of(fb_helper, struct intel_fbdev, helper);
  65         int ret;
  66 
  67         ret = drm_fb_helper_set_par(info);
  68         if (ret == 0)
  69                 intel_fbdev_invalidate(ifbdev);
  70 
  71         return ret;
  72 }
  73 
  74 static int intel_fbdev_blank(int blank, struct fb_info *info)
  75 {
  76         struct drm_fb_helper *fb_helper = info->par;
  77         struct intel_fbdev *ifbdev =
  78                 container_of(fb_helper, struct intel_fbdev, helper);
  79         int ret;
  80 
  81         ret = drm_fb_helper_blank(blank, info);
  82         if (ret == 0)
  83                 intel_fbdev_invalidate(ifbdev);
  84 
  85         return ret;
  86 }
  87 
  88 static int intel_fbdev_pan_display(struct fb_var_screeninfo *var,
  89                                    struct fb_info *info)
  90 {
  91         struct drm_fb_helper *fb_helper = info->par;
  92         struct intel_fbdev *ifbdev =
  93                 container_of(fb_helper, struct intel_fbdev, helper);
  94         int ret;
  95 
  96         ret = drm_fb_helper_pan_display(var, info);
  97         if (ret == 0)
  98                 intel_fbdev_invalidate(ifbdev);
  99 
 100         return ret;
 101 }
 102 
 103 static struct fb_ops intelfb_ops = {
 104         .owner = THIS_MODULE,
 105         DRM_FB_HELPER_DEFAULT_OPS,
 106         .fb_set_par = intel_fbdev_set_par,
 107         .fb_fillrect = drm_fb_helper_cfb_fillrect,
 108         .fb_copyarea = drm_fb_helper_cfb_copyarea,
 109         .fb_imageblit = drm_fb_helper_cfb_imageblit,
 110         .fb_pan_display = intel_fbdev_pan_display,
 111         .fb_blank = intel_fbdev_blank,
 112 };
 113 
 114 static int intelfb_alloc(struct drm_fb_helper *helper,
 115                          struct drm_fb_helper_surface_size *sizes)
 116 {
 117         struct intel_fbdev *ifbdev =
 118                 container_of(helper, struct intel_fbdev, helper);
 119         struct drm_framebuffer *fb;
 120         struct drm_device *dev = helper->dev;
 121         struct drm_i915_private *dev_priv = to_i915(dev);
 122         struct drm_mode_fb_cmd2 mode_cmd = {};
 123         struct drm_i915_gem_object *obj;
 124         int size;
 125 
 126         /* we don't do packed 24bpp */
 127         if (sizes->surface_bpp == 24)
 128                 sizes->surface_bpp = 32;
 129 
 130         mode_cmd.width = sizes->surface_width;
 131         mode_cmd.height = sizes->surface_height;
 132 
 133         mode_cmd.pitches[0] = ALIGN(mode_cmd.width *
 134                                     DIV_ROUND_UP(sizes->surface_bpp, 8), 64);
 135         mode_cmd.pixel_format = drm_mode_legacy_fb_format(sizes->surface_bpp,
 136                                                           sizes->surface_depth);
 137 
 138         size = mode_cmd.pitches[0] * mode_cmd.height;
 139         size = PAGE_ALIGN(size);
 140 
 141         /* If the FB is too big, just don't use it since fbdev is not very
 142          * important and we should probably use that space with FBC or other
 143          * features. */
 144         obj = NULL;
 145         if (size * 2 < dev_priv->stolen_usable_size)
 146                 obj = i915_gem_object_create_stolen(dev_priv, size);
 147         if (obj == NULL)
 148                 obj = i915_gem_object_create_shmem(dev_priv, size);
 149         if (IS_ERR(obj)) {
 150                 DRM_ERROR("failed to allocate framebuffer\n");
 151                 return PTR_ERR(obj);
 152         }
 153 
 154         fb = intel_framebuffer_create(obj, &mode_cmd);
 155         i915_gem_object_put(obj);
 156         if (IS_ERR(fb))
 157                 return PTR_ERR(fb);
 158 
 159         ifbdev->fb = to_intel_framebuffer(fb);
 160         return 0;
 161 }
 162 
 163 static int intelfb_create(struct drm_fb_helper *helper,
 164                           struct drm_fb_helper_surface_size *sizes)
 165 {
 166         struct intel_fbdev *ifbdev =
 167                 container_of(helper, struct intel_fbdev, helper);
 168         struct intel_framebuffer *intel_fb = ifbdev->fb;
 169         struct drm_device *dev = helper->dev;
 170         struct drm_i915_private *dev_priv = to_i915(dev);
 171         struct pci_dev *pdev = dev_priv->drm.pdev;
 172         struct i915_ggtt *ggtt = &dev_priv->ggtt;
 173         const struct i915_ggtt_view view = {
 174                 .type = I915_GGTT_VIEW_NORMAL,
 175         };
 176         intel_wakeref_t wakeref;
 177         struct fb_info *info;
 178         struct i915_vma *vma;
 179         unsigned long flags = 0;
 180         bool prealloc = false;
 181         void __iomem *vaddr;
 182         int ret;
 183 
 184         if (intel_fb &&
 185             (sizes->fb_width > intel_fb->base.width ||
 186              sizes->fb_height > intel_fb->base.height)) {
 187                 DRM_DEBUG_KMS("BIOS fb too small (%dx%d), we require (%dx%d),"
 188                               " releasing it\n",
 189                               intel_fb->base.width, intel_fb->base.height,
 190                               sizes->fb_width, sizes->fb_height);
 191                 drm_framebuffer_put(&intel_fb->base);
 192                 intel_fb = ifbdev->fb = NULL;
 193         }
 194         if (!intel_fb || WARN_ON(!intel_fb_obj(&intel_fb->base))) {
 195                 DRM_DEBUG_KMS("no BIOS fb, allocating a new one\n");
 196                 ret = intelfb_alloc(helper, sizes);
 197                 if (ret)
 198                         return ret;
 199                 intel_fb = ifbdev->fb;
 200         } else {
 201                 DRM_DEBUG_KMS("re-using BIOS fb\n");
 202                 prealloc = true;
 203                 sizes->fb_width = intel_fb->base.width;
 204                 sizes->fb_height = intel_fb->base.height;
 205         }
 206 
 207         mutex_lock(&dev->struct_mutex);
 208         wakeref = intel_runtime_pm_get(&dev_priv->runtime_pm);
 209 
 210         /* Pin the GGTT vma for our access via info->screen_base.
 211          * This also validates that any existing fb inherited from the
 212          * BIOS is suitable for own access.
 213          */
 214         vma = intel_pin_and_fence_fb_obj(&ifbdev->fb->base,
 215                                          &view, false, &flags);
 216         if (IS_ERR(vma)) {
 217                 ret = PTR_ERR(vma);
 218                 goto out_unlock;
 219         }
 220 
 221         intel_frontbuffer_flush(to_frontbuffer(ifbdev), ORIGIN_DIRTYFB);
 222 
 223         info = drm_fb_helper_alloc_fbi(helper);
 224         if (IS_ERR(info)) {
 225                 DRM_ERROR("Failed to allocate fb_info\n");
 226                 ret = PTR_ERR(info);
 227                 goto out_unpin;
 228         }
 229 
 230         ifbdev->helper.fb = &ifbdev->fb->base;
 231 
 232         info->fbops = &intelfb_ops;
 233 
 234         /* setup aperture base/size for vesafb takeover */
 235         info->apertures->ranges[0].base = ggtt->gmadr.start;
 236         info->apertures->ranges[0].size = ggtt->mappable_end;
 237 
 238         /* Our framebuffer is the entirety of fbdev's system memory */
 239         info->fix.smem_start =
 240                 (unsigned long)(ggtt->gmadr.start + vma->node.start);
 241         info->fix.smem_len = vma->node.size;
 242 
 243         vaddr = i915_vma_pin_iomap(vma);
 244         if (IS_ERR(vaddr)) {
 245                 DRM_ERROR("Failed to remap framebuffer into virtual memory\n");
 246                 ret = PTR_ERR(vaddr);
 247                 goto out_unpin;
 248         }
 249         info->screen_base = vaddr;
 250         info->screen_size = vma->node.size;
 251 
 252         drm_fb_helper_fill_info(info, &ifbdev->helper, sizes);
 253 
 254         /* If the object is shmemfs backed, it will have given us zeroed pages.
 255          * If the object is stolen however, it will be full of whatever
 256          * garbage was left in there.
 257          */
 258         if (vma->obj->stolen && !prealloc)
 259                 memset_io(info->screen_base, 0, info->screen_size);
 260 
 261         /* Use default scratch pixmap (info->pixmap.flags = FB_PIXMAP_SYSTEM) */
 262 
 263         DRM_DEBUG_KMS("allocated %dx%d fb: 0x%08x\n",
 264                       ifbdev->fb->base.width, ifbdev->fb->base.height,
 265                       i915_ggtt_offset(vma));
 266         ifbdev->vma = vma;
 267         ifbdev->vma_flags = flags;
 268 
 269         intel_runtime_pm_put(&dev_priv->runtime_pm, wakeref);
 270         mutex_unlock(&dev->struct_mutex);
 271         vga_switcheroo_client_fb_set(pdev, info);
 272         return 0;
 273 
 274 out_unpin:
 275         intel_unpin_fb_vma(vma, flags);
 276 out_unlock:
 277         intel_runtime_pm_put(&dev_priv->runtime_pm, wakeref);
 278         mutex_unlock(&dev->struct_mutex);
 279         return ret;
 280 }
 281 
 282 static const struct drm_fb_helper_funcs intel_fb_helper_funcs = {
 283         .fb_probe = intelfb_create,
 284 };
 285 
 286 static void intel_fbdev_destroy(struct intel_fbdev *ifbdev)
 287 {
 288         /* We rely on the object-free to release the VMA pinning for
 289          * the info->screen_base mmaping. Leaking the VMA is simpler than
 290          * trying to rectify all the possible error paths leading here.
 291          */
 292 
 293         drm_fb_helper_fini(&ifbdev->helper);
 294 
 295         if (ifbdev->vma) {
 296                 mutex_lock(&ifbdev->helper.dev->struct_mutex);
 297                 intel_unpin_fb_vma(ifbdev->vma, ifbdev->vma_flags);
 298                 mutex_unlock(&ifbdev->helper.dev->struct_mutex);
 299         }
 300 
 301         if (ifbdev->fb)
 302                 drm_framebuffer_remove(&ifbdev->fb->base);
 303 
 304         kfree(ifbdev);
 305 }
 306 
 307 /*
 308  * Build an intel_fbdev struct using a BIOS allocated framebuffer, if possible.
 309  * The core display code will have read out the current plane configuration,
 310  * so we use that to figure out if there's an object for us to use as the
 311  * fb, and if so, we re-use it for the fbdev configuration.
 312  *
 313  * Note we only support a single fb shared across pipes for boot (mostly for
 314  * fbcon), so we just find the biggest and use that.
 315  */
 316 static bool intel_fbdev_init_bios(struct drm_device *dev,
 317                                  struct intel_fbdev *ifbdev)
 318 {
 319         struct intel_framebuffer *fb = NULL;
 320         struct drm_crtc *crtc;
 321         struct intel_crtc *intel_crtc;
 322         unsigned int max_size = 0;
 323 
 324         /* Find the largest fb */
 325         for_each_crtc(dev, crtc) {
 326                 struct drm_i915_gem_object *obj =
 327                         intel_fb_obj(crtc->primary->state->fb);
 328                 intel_crtc = to_intel_crtc(crtc);
 329 
 330                 if (!crtc->state->active || !obj) {
 331                         DRM_DEBUG_KMS("pipe %c not active or no fb, skipping\n",
 332                                       pipe_name(intel_crtc->pipe));
 333                         continue;
 334                 }
 335 
 336                 if (obj->base.size > max_size) {
 337                         DRM_DEBUG_KMS("found possible fb from plane %c\n",
 338                                       pipe_name(intel_crtc->pipe));
 339                         fb = to_intel_framebuffer(crtc->primary->state->fb);
 340                         max_size = obj->base.size;
 341                 }
 342         }
 343 
 344         if (!fb) {
 345                 DRM_DEBUG_KMS("no active fbs found, not using BIOS config\n");
 346                 goto out;
 347         }
 348 
 349         /* Now make sure all the pipes will fit into it */
 350         for_each_crtc(dev, crtc) {
 351                 unsigned int cur_size;
 352 
 353                 intel_crtc = to_intel_crtc(crtc);
 354 
 355                 if (!crtc->state->active) {
 356                         DRM_DEBUG_KMS("pipe %c not active, skipping\n",
 357                                       pipe_name(intel_crtc->pipe));
 358                         continue;
 359                 }
 360 
 361                 DRM_DEBUG_KMS("checking plane %c for BIOS fb\n",
 362                               pipe_name(intel_crtc->pipe));
 363 
 364                 /*
 365                  * See if the plane fb we found above will fit on this
 366                  * pipe.  Note we need to use the selected fb's pitch and bpp
 367                  * rather than the current pipe's, since they differ.
 368                  */
 369                 cur_size = crtc->state->adjusted_mode.crtc_hdisplay;
 370                 cur_size = cur_size * fb->base.format->cpp[0];
 371                 if (fb->base.pitches[0] < cur_size) {
 372                         DRM_DEBUG_KMS("fb not wide enough for plane %c (%d vs %d)\n",
 373                                       pipe_name(intel_crtc->pipe),
 374                                       cur_size, fb->base.pitches[0]);
 375                         fb = NULL;
 376                         break;
 377                 }
 378 
 379                 cur_size = crtc->state->adjusted_mode.crtc_vdisplay;
 380                 cur_size = intel_fb_align_height(&fb->base, 0, cur_size);
 381                 cur_size *= fb->base.pitches[0];
 382                 DRM_DEBUG_KMS("pipe %c area: %dx%d, bpp: %d, size: %d\n",
 383                               pipe_name(intel_crtc->pipe),
 384                               crtc->state->adjusted_mode.crtc_hdisplay,
 385                               crtc->state->adjusted_mode.crtc_vdisplay,
 386                               fb->base.format->cpp[0] * 8,
 387                               cur_size);
 388 
 389                 if (cur_size > max_size) {
 390                         DRM_DEBUG_KMS("fb not big enough for plane %c (%d vs %d)\n",
 391                                       pipe_name(intel_crtc->pipe),
 392                                       cur_size, max_size);
 393                         fb = NULL;
 394                         break;
 395                 }
 396 
 397                 DRM_DEBUG_KMS("fb big enough for plane %c (%d >= %d)\n",
 398                               pipe_name(intel_crtc->pipe),
 399                               max_size, cur_size);
 400         }
 401 
 402         if (!fb) {
 403                 DRM_DEBUG_KMS("BIOS fb not suitable for all pipes, not using\n");
 404                 goto out;
 405         }
 406 
 407         ifbdev->preferred_bpp = fb->base.format->cpp[0] * 8;
 408         ifbdev->fb = fb;
 409 
 410         drm_framebuffer_get(&ifbdev->fb->base);
 411 
 412         /* Final pass to check if any active pipes don't have fbs */
 413         for_each_crtc(dev, crtc) {
 414                 intel_crtc = to_intel_crtc(crtc);
 415 
 416                 if (!crtc->state->active)
 417                         continue;
 418 
 419                 WARN(!crtc->primary->state->fb,
 420                      "re-used BIOS config but lost an fb on crtc %d\n",
 421                      crtc->base.id);
 422         }
 423 
 424 
 425         DRM_DEBUG_KMS("using BIOS fb for initial console\n");
 426         return true;
 427 
 428 out:
 429 
 430         return false;
 431 }
 432 
 433 static void intel_fbdev_suspend_worker(struct work_struct *work)
 434 {
 435         intel_fbdev_set_suspend(&container_of(work,
 436                                               struct drm_i915_private,
 437                                               fbdev_suspend_work)->drm,
 438                                 FBINFO_STATE_RUNNING,
 439                                 true);
 440 }
 441 
 442 int intel_fbdev_init(struct drm_device *dev)
 443 {
 444         struct drm_i915_private *dev_priv = to_i915(dev);
 445         struct intel_fbdev *ifbdev;
 446         int ret;
 447 
 448         if (WARN_ON(!HAS_DISPLAY(dev_priv)))
 449                 return -ENODEV;
 450 
 451         ifbdev = kzalloc(sizeof(struct intel_fbdev), GFP_KERNEL);
 452         if (ifbdev == NULL)
 453                 return -ENOMEM;
 454 
 455         mutex_init(&ifbdev->hpd_lock);
 456         drm_fb_helper_prepare(dev, &ifbdev->helper, &intel_fb_helper_funcs);
 457 
 458         if (!intel_fbdev_init_bios(dev, ifbdev))
 459                 ifbdev->preferred_bpp = 32;
 460 
 461         ret = drm_fb_helper_init(dev, &ifbdev->helper, 4);
 462         if (ret) {
 463                 kfree(ifbdev);
 464                 return ret;
 465         }
 466 
 467         dev_priv->fbdev = ifbdev;
 468         INIT_WORK(&dev_priv->fbdev_suspend_work, intel_fbdev_suspend_worker);
 469 
 470         drm_fb_helper_single_add_all_connectors(&ifbdev->helper);
 471 
 472         return 0;
 473 }
 474 
 475 static void intel_fbdev_initial_config(void *data, async_cookie_t cookie)
 476 {
 477         struct intel_fbdev *ifbdev = data;
 478 
 479         /* Due to peculiar init order wrt to hpd handling this is separate. */
 480         if (drm_fb_helper_initial_config(&ifbdev->helper,
 481                                          ifbdev->preferred_bpp))
 482                 intel_fbdev_unregister(to_i915(ifbdev->helper.dev));
 483 }
 484 
 485 void intel_fbdev_initial_config_async(struct drm_device *dev)
 486 {
 487         struct intel_fbdev *ifbdev = to_i915(dev)->fbdev;
 488 
 489         if (!ifbdev)
 490                 return;
 491 
 492         ifbdev->cookie = async_schedule(intel_fbdev_initial_config, ifbdev);
 493 }
 494 
 495 static void intel_fbdev_sync(struct intel_fbdev *ifbdev)
 496 {
 497         if (!ifbdev->cookie)
 498                 return;
 499 
 500         /* Only serialises with all preceding async calls, hence +1 */
 501         async_synchronize_cookie(ifbdev->cookie + 1);
 502         ifbdev->cookie = 0;
 503 }
 504 
 505 void intel_fbdev_unregister(struct drm_i915_private *dev_priv)
 506 {
 507         struct intel_fbdev *ifbdev = dev_priv->fbdev;
 508 
 509         if (!ifbdev)
 510                 return;
 511 
 512         cancel_work_sync(&dev_priv->fbdev_suspend_work);
 513         if (!current_is_async())
 514                 intel_fbdev_sync(ifbdev);
 515 
 516         drm_fb_helper_unregister_fbi(&ifbdev->helper);
 517 }
 518 
 519 void intel_fbdev_fini(struct drm_i915_private *dev_priv)
 520 {
 521         struct intel_fbdev *ifbdev = fetch_and_zero(&dev_priv->fbdev);
 522 
 523         if (!ifbdev)
 524                 return;
 525 
 526         intel_fbdev_destroy(ifbdev);
 527 }
 528 
 529 /* Suspends/resumes fbdev processing of incoming HPD events. When resuming HPD
 530  * processing, fbdev will perform a full connector reprobe if a hotplug event
 531  * was received while HPD was suspended.
 532  */
 533 static void intel_fbdev_hpd_set_suspend(struct intel_fbdev *ifbdev, int state)
 534 {
 535         bool send_hpd = false;
 536 
 537         mutex_lock(&ifbdev->hpd_lock);
 538         ifbdev->hpd_suspended = state == FBINFO_STATE_SUSPENDED;
 539         send_hpd = !ifbdev->hpd_suspended && ifbdev->hpd_waiting;
 540         ifbdev->hpd_waiting = false;
 541         mutex_unlock(&ifbdev->hpd_lock);
 542 
 543         if (send_hpd) {
 544                 DRM_DEBUG_KMS("Handling delayed fbcon HPD event\n");
 545                 drm_fb_helper_hotplug_event(&ifbdev->helper);
 546         }
 547 }
 548 
 549 void intel_fbdev_set_suspend(struct drm_device *dev, int state, bool synchronous)
 550 {
 551         struct drm_i915_private *dev_priv = to_i915(dev);
 552         struct intel_fbdev *ifbdev = dev_priv->fbdev;
 553         struct fb_info *info;
 554 
 555         if (!ifbdev || !ifbdev->vma)
 556                 return;
 557 
 558         info = ifbdev->helper.fbdev;
 559 
 560         if (synchronous) {
 561                 /* Flush any pending work to turn the console on, and then
 562                  * wait to turn it off. It must be synchronous as we are
 563                  * about to suspend or unload the driver.
 564                  *
 565                  * Note that from within the work-handler, we cannot flush
 566                  * ourselves, so only flush outstanding work upon suspend!
 567                  */
 568                 if (state != FBINFO_STATE_RUNNING)
 569                         flush_work(&dev_priv->fbdev_suspend_work);
 570 
 571                 console_lock();
 572         } else {
 573                 /*
 574                  * The console lock can be pretty contented on resume due
 575                  * to all the printk activity.  Try to keep it out of the hot
 576                  * path of resume if possible.
 577                  */
 578                 WARN_ON(state != FBINFO_STATE_RUNNING);
 579                 if (!console_trylock()) {
 580                         /* Don't block our own workqueue as this can
 581                          * be run in parallel with other i915.ko tasks.
 582                          */
 583                         schedule_work(&dev_priv->fbdev_suspend_work);
 584                         return;
 585                 }
 586         }
 587 
 588         /* On resume from hibernation: If the object is shmemfs backed, it has
 589          * been restored from swap. If the object is stolen however, it will be
 590          * full of whatever garbage was left in there.
 591          */
 592         if (state == FBINFO_STATE_RUNNING &&
 593             intel_fb_obj(&ifbdev->fb->base)->stolen)
 594                 memset_io(info->screen_base, 0, info->screen_size);
 595 
 596         drm_fb_helper_set_suspend(&ifbdev->helper, state);
 597         console_unlock();
 598 
 599         intel_fbdev_hpd_set_suspend(ifbdev, state);
 600 }
 601 
 602 void intel_fbdev_output_poll_changed(struct drm_device *dev)
 603 {
 604         struct intel_fbdev *ifbdev = to_i915(dev)->fbdev;
 605         bool send_hpd;
 606 
 607         if (!ifbdev)
 608                 return;
 609 
 610         intel_fbdev_sync(ifbdev);
 611 
 612         mutex_lock(&ifbdev->hpd_lock);
 613         send_hpd = !ifbdev->hpd_suspended;
 614         ifbdev->hpd_waiting = true;
 615         mutex_unlock(&ifbdev->hpd_lock);
 616 
 617         if (send_hpd && (ifbdev->vma || ifbdev->helper.deferred_setup))
 618                 drm_fb_helper_hotplug_event(&ifbdev->helper);
 619 }
 620 
 621 void intel_fbdev_restore_mode(struct drm_device *dev)
 622 {
 623         struct intel_fbdev *ifbdev = to_i915(dev)->fbdev;
 624 
 625         if (!ifbdev)
 626                 return;
 627 
 628         intel_fbdev_sync(ifbdev);
 629         if (!ifbdev->vma)
 630                 return;
 631 
 632         if (drm_fb_helper_restore_fbdev_mode_unlocked(&ifbdev->helper) == 0)
 633                 intel_fbdev_invalidate(ifbdev);
 634 }