drivers/gpu/drm/drm_fb_cma_helper.c

   1 /*
   2  * drm kms/fb cma (contiguous memory allocator) helper functions
   3  *
   4  * Copyright (C) 2012 Analog Device Inc.
   5  *   Author: Lars-Peter Clausen <[email protected]>
   6  *
   7  * Based on udl_fbdev.c
   8  *  Copyright (C) 2012 Red Hat
   9  *
  10  * This program is free software; you can redistribute it and/or
  11  * modify it under the terms of the GNU General Public License
  12  * as published by the Free Software Foundation; either version 2
  13  * of the License, or (at your option) any later version.
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  */
  19
  20 #include <drm/drmP.h>
  21 #include <drm/drm_fb_helper.h>
  22 #include <drm/drm_framebuffer.h>
  23 #include <drm/drm_gem_cma_helper.h>
  24 #include <drm/drm_gem_framebuffer_helper.h>
  25 #include <drm/drm_fb_cma_helper.h>
  26 #include <linux/module.h>
  27
  28 #define DEFAULT_FBDEFIO_DELAY_MS 50
  29
  30 struct drm_fbdev_cma {
  31         struct drm_fb_helper    fb_helper;
  32         const struct drm_framebuffer_funcs *fb_funcs;
  33 };
  34
  35 /**
  36  * DOC: framebuffer cma helper functions
  37  *
  38  * Provides helper functions for creating a cma (contiguous memory allocator)
  39  * backed framebuffer.
  40  *
  41  * drm_gem_fb_create() is used in the &drm_mode_config_funcs.fb_create
  42  * callback function to create a cma backed framebuffer.
  43  *
  44  * An fbdev framebuffer backed by cma is also available by calling
  45  * drm_fbdev_cma_init(). drm_fbdev_cma_fini() tears it down.
  46  * If the &drm_framebuffer_funcs.dirty callback is set, fb_deferred_io will be
  47  * set up automatically. &drm_framebuffer_funcs.dirty is called by
  48  * drm_fb_helper_deferred_io() in process context (&struct delayed_work).
  49  *
  50  * Example fbdev deferred io code::
  51  *
  52  *     static int driver_fb_dirty(struct drm_framebuffer *fb,
  53  *                                struct drm_file *file_priv,
  54  *                                unsigned flags, unsigned color,
  55  *                                struct drm_clip_rect *clips,
  56  *                                unsigned num_clips)
  57  *     {
  58  *         struct drm_gem_cma_object *cma = drm_fb_cma_get_gem_obj(fb, 0);
  59  *         ... push changes ...
  60  *         return 0;
  61  *     }
  62  *
  63  *     static struct drm_framebuffer_funcs driver_fb_funcs = {
  64  *         .destroy       = drm_gem_fb_destroy,
  65  *         .create_handle = drm_gem_fb_create_handle,
  66  *         .dirty         = driver_fb_dirty,
  67  *     };
  68  *
  69  * Initialize::
  70  *
  71  *     fbdev = drm_fbdev_cma_init_with_funcs(dev, 16,
  72  *                                           dev->mode_config.num_crtc,
  73  *                                           dev->mode_config.num_connector,
  74  *                                           &driver_fb_funcs);
  75  *
  76  */
  77
  78 static inline struct drm_fbdev_cma *to_fbdev_cma(struct drm_fb_helper *helper)
  79 {
  80         return container_of(helper, struct drm_fbdev_cma, fb_helper);
  81 }
  82
  83 /**
  84  * drm_fb_cma_get_gem_obj() - Get CMA GEM object for framebuffer
  85  * @fb: The framebuffer
  86  * @plane: Which plane
  87  *
  88  * Return the CMA GEM object for given framebuffer.
  89  *
  90  * This function will usually be called from the CRTC callback functions.
  91  */
  92 struct drm_gem_cma_object *drm_fb_cma_get_gem_obj(struct drm_framebuffer *fb,
  93                                                   unsigned int plane)
  94 {
  95         struct drm_gem_object *gem;
  96
  97         gem = drm_gem_fb_get_obj(fb, plane);
  98         if (!gem)
  99                 return NULL;
 100
 101         return to_drm_gem_cma_obj(gem);
 102 }
 103 EXPORT_SYMBOL_GPL(drm_fb_cma_get_gem_obj);
 104
 105 /**
 106  * drm_fb_cma_get_gem_addr() - Get physical address for framebuffer
 107  * @fb: The framebuffer
 108  * @state: Which state of drm plane
 109  * @plane: Which plane
 110  * Return the CMA GEM address for given framebuffer.
 111  *
 112  * This function will usually be called from the PLANE callback functions.
 113  */
 114 dma_addr_t drm_fb_cma_get_gem_addr(struct drm_framebuffer *fb,
 115                                    struct drm_plane_state *state,
 116                                    unsigned int plane)
 117 {
 118         struct drm_gem_cma_object *obj;
 119         dma_addr_t paddr;
 120
 121         obj = drm_fb_cma_get_gem_obj(fb, plane);
 122         if (!obj)
 123                 return 0;
 124
 125         paddr = obj->paddr + fb->offsets[plane];
 126         paddr += fb->format->cpp[plane] * (state->src_x >> 16);
 127         paddr += fb->pitches[plane] * (state->src_y >> 16);
 128
 129         return paddr;
 130 }
 131 EXPORT_SYMBOL_GPL(drm_fb_cma_get_gem_addr);
 132
 133 #ifdef CONFIG_DEBUG_FS
 134 static void drm_fb_cma_describe(struct drm_framebuffer *fb, struct seq_file *m)
 135 {
 136         int i;
 137
 138         seq_printf(m, "fb: %dx%d@%4.4s\n", fb->width, fb->height,
 139                         (char *)&fb->format->format);
 140
 141         for (i = 0; i < fb->format->num_planes; i++) {
 142                 seq_printf(m, "   %d: offset=%d pitch=%d, obj: ",
 143                                 i, fb->offsets[i], fb->pitches[i]);
 144                 drm_gem_cma_describe(drm_fb_cma_get_gem_obj(fb, i), m);
 145         }
 146 }
 147
 148 /**
 149  * drm_fb_cma_debugfs_show() - Helper to list CMA framebuffer objects
 150  *                             in debugfs.
 151  * @m: output file
 152  * @arg: private data for the callback
 153  */
 154 int drm_fb_cma_debugfs_show(struct seq_file *m, void *arg)
 155 {
 156         struct drm_info_node *node = (struct drm_info_node *) m->private;
 157         struct drm_device *dev = node->minor->dev;
 158         struct drm_framebuffer *fb;
 159
 160         mutex_lock(&dev->mode_config.fb_lock);
 161         drm_for_each_fb(fb, dev)
 162                 drm_fb_cma_describe(fb, m);
 163         mutex_unlock(&dev->mode_config.fb_lock);
 164
 165         return 0;
 166 }
 167 EXPORT_SYMBOL_GPL(drm_fb_cma_debugfs_show);
 168 #endif
 169
 170 static int drm_fb_cma_mmap(struct fb_info *info, struct vm_area_struct *vma)
 171 {
 172         return dma_mmap_writecombine(info->device, vma, info->screen_base,
 173                                      info->fix.smem_start, info->fix.smem_len);
 174 }
 175
 176 static struct fb_ops drm_fbdev_cma_ops = {
 177         .owner          = THIS_MODULE,
 178         DRM_FB_HELPER_DEFAULT_OPS,
 179         .fb_fillrect    = drm_fb_helper_sys_fillrect,
 180         .fb_copyarea    = drm_fb_helper_sys_copyarea,
 181         .fb_imageblit   = drm_fb_helper_sys_imageblit,
 182         .fb_mmap        = drm_fb_cma_mmap,
 183 };
 184
 185 static int drm_fbdev_cma_deferred_io_mmap(struct fb_info *info,
 186                                           struct vm_area_struct *vma)
 187 {
 188         fb_deferred_io_mmap(info, vma);
 189         vma->vm_page_prot = pgprot_writecombine(vma->vm_page_prot);
 190
 191         return 0;
 192 }
 193
 194 static int drm_fbdev_cma_defio_init(struct fb_info *fbi,
 195                                     struct drm_gem_cma_object *cma_obj)
 196 {
 197         struct fb_deferred_io *fbdefio;
 198         struct fb_ops *fbops;
 199
 200         /*
 201          * Per device structures are needed because:
 202          * fbops: fb_deferred_io_cleanup() clears fbops.fb_mmap
 203          * fbdefio: individual delays
 204          */
 205         fbdefio = kzalloc(sizeof(*fbdefio), GFP_KERNEL);
 206         fbops = kzalloc(sizeof(*fbops), GFP_KERNEL);
 207         if (!fbdefio || !fbops) {
 208                 kfree(fbdefio);
 209                 kfree(fbops);
 210                 return -ENOMEM;
 211         }
 212
 213         /* can't be offset from vaddr since dirty() uses cma_obj */
 214         fbi->screen_buffer = cma_obj->vaddr;
 215         /* fb_deferred_io_fault() needs a physical address */
 216         fbi->fix.smem_start = page_to_phys(virt_to_page(fbi->screen_buffer));
 217
 218         *fbops = *fbi->fbops;
 219         fbi->fbops = fbops;
 220
 221         fbdefio->delay = msecs_to_jiffies(DEFAULT_FBDEFIO_DELAY_MS);
 222         fbdefio->deferred_io = drm_fb_helper_deferred_io;
 223         fbi->fbdefio = fbdefio;
 224         fb_deferred_io_init(fbi);
 225         fbi->fbops->fb_mmap = drm_fbdev_cma_deferred_io_mmap;
 226
 227         return 0;
 228 }
 229
 230 static void drm_fbdev_cma_defio_fini(struct fb_info *fbi)
 231 {
 232         if (!fbi->fbdefio)
 233                 return;
 234
 235         fb_deferred_io_cleanup(fbi);
 236         kfree(fbi->fbdefio);
 237         kfree(fbi->fbops);
 238 }
 239
 240 static int
 241 drm_fbdev_cma_create(struct drm_fb_helper *helper,
 242         struct drm_fb_helper_surface_size *sizes)
 243 {
 244         struct drm_fbdev_cma *fbdev_cma = to_fbdev_cma(helper);
 245         struct drm_device *dev = helper->dev;
 246         struct drm_gem_cma_object *obj;
 247         struct drm_framebuffer *fb;
 248         unsigned int bytes_per_pixel;
 249         unsigned long offset;
 250         struct fb_info *fbi;
 251         size_t size;
 252         int ret;
 253
 254         DRM_DEBUG_KMS("surface width(%d), height(%d) and bpp(%d)\n",
 255                         sizes->surface_width, sizes->surface_height,
 256                         sizes->surface_bpp);
 257
 258         bytes_per_pixel = DIV_ROUND_UP(sizes->surface_bpp, 8);
 259         size = sizes->surface_width * sizes->surface_height * bytes_per_pixel;
 260         obj = drm_gem_cma_create(dev, size);
 261         if (IS_ERR(obj))
 262                 return -ENOMEM;
 263
 264         fbi = drm_fb_helper_alloc_fbi(helper);
 265         if (IS_ERR(fbi)) {
 266                 ret = PTR_ERR(fbi);
 267                 goto err_gem_free_object;
 268         }
 269
 270         fb = drm_gem_fbdev_fb_create(dev, sizes, 0, &obj->base,
 271                                      fbdev_cma->fb_funcs);
 272         if (IS_ERR(fb)) {
 273                 dev_err(dev->dev, "Failed to allocate DRM framebuffer.\n");
 274                 ret = PTR_ERR(fb);
 275                 goto err_fb_info_destroy;
 276         }
 277
 278         helper->fb = fb;
 279
 280         fbi->par = helper;
 281         fbi->flags = FBINFO_FLAG_DEFAULT;
 282         fbi->fbops = &drm_fbdev_cma_ops;
 283
 284         drm_fb_helper_fill_fix(fbi, fb->pitches[0], fb->format->depth);
 285         drm_fb_helper_fill_var(fbi, helper, sizes->fb_width, sizes->fb_height);
 286
 287         offset = fbi->var.xoffset * bytes_per_pixel;
 288         offset += fbi->var.yoffset * fb->pitches[0];
 289
 290         dev->mode_config.fb_base = (resource_size_t)obj->paddr;
 291         fbi->screen_base = obj->vaddr + offset;
 292         fbi->fix.smem_start = (unsigned long)(obj->paddr + offset);
 293         fbi->screen_size = size;
 294         fbi->fix.smem_len = size;
 295
 296         if (fbdev_cma->fb_funcs->dirty) {
 297                 ret = drm_fbdev_cma_defio_init(fbi, obj);
 298                 if (ret)
 299                         goto err_cma_destroy;
 300         }
 301
 302         return 0;
 303
 304 err_cma_destroy:
 305         drm_framebuffer_remove(fb);
 306 err_fb_info_destroy:
 307         drm_fb_helper_fini(helper);
 308 err_gem_free_object:
 309         drm_gem_object_put_unlocked(&obj->base);
 310         return ret;
 311 }
 312
 313 static const struct drm_fb_helper_funcs drm_fb_cma_helper_funcs = {
 314         .fb_probe = drm_fbdev_cma_create,
 315 };
 316
 317 /**
 318  * drm_fbdev_cma_init_with_funcs() - Allocate and initializes a drm_fbdev_cma struct
 319  * @dev: DRM device
 320  * @preferred_bpp: Preferred bits per pixel for the device
 321  * @max_conn_count: Maximum number of connectors
 322  * @funcs: fb helper functions, in particular a custom dirty() callback
 323  *
 324  * Returns a newly allocated drm_fbdev_cma struct or a ERR_PTR.
 325  */
 326 struct drm_fbdev_cma *drm_fbdev_cma_init_with_funcs(struct drm_device *dev,
 327         unsigned int preferred_bpp, unsigned int max_conn_count,
 328         const struct drm_framebuffer_funcs *funcs)
 329 {
 330         struct drm_fbdev_cma *fbdev_cma;
 331         struct drm_fb_helper *helper;
 332         int ret;
 333
 334         fbdev_cma = kzalloc(sizeof(*fbdev_cma), GFP_KERNEL);
 335         if (!fbdev_cma) {
 336                 dev_err(dev->dev, "Failed to allocate drm fbdev.\n");
 337                 return ERR_PTR(-ENOMEM);
 338         }
 339         fbdev_cma->fb_funcs = funcs;
 340
 341         helper = &fbdev_cma->fb_helper;
 342
 343         drm_fb_helper_prepare(dev, helper, &drm_fb_cma_helper_funcs);
 344
 345         ret = drm_fb_helper_init(dev, helper, max_conn_count);
 346         if (ret < 0) {
 347                 dev_err(dev->dev, "Failed to initialize drm fb helper.\n");
 348                 goto err_free;
 349         }
 350
 351         ret = drm_fb_helper_single_add_all_connectors(helper);
 352         if (ret < 0) {
 353                 dev_err(dev->dev, "Failed to add connectors.\n");
 354                 goto err_drm_fb_helper_fini;
 355
 356         }
 357
 358         ret = drm_fb_helper_initial_config(helper, preferred_bpp);
 359         if (ret < 0) {
 360                 dev_err(dev->dev, "Failed to set initial hw configuration.\n");
 361                 goto err_drm_fb_helper_fini;
 362         }
 363
 364         return fbdev_cma;
 365
 366 err_drm_fb_helper_fini:
 367         drm_fb_helper_fini(helper);
 368 err_free:
 369         kfree(fbdev_cma);
 370
 371         return ERR_PTR(ret);
 372 }
 373 EXPORT_SYMBOL_GPL(drm_fbdev_cma_init_with_funcs);
 374
 375 static const struct drm_framebuffer_funcs drm_fb_cma_funcs = {
 376         .destroy        = drm_gem_fb_destroy,
 377         .create_handle  = drm_gem_fb_create_handle,
 378 };
 379
 380 /**
 381  * drm_fbdev_cma_init() - Allocate and initializes a drm_fbdev_cma struct
 382  * @dev: DRM device
 383  * @preferred_bpp: Preferred bits per pixel for the device
 384  * @max_conn_count: Maximum number of connectors
 385  *
 386  * Returns a newly allocated drm_fbdev_cma struct or a ERR_PTR.
 387  */
 388 struct drm_fbdev_cma *drm_fbdev_cma_init(struct drm_device *dev,
 389         unsigned int preferred_bpp, unsigned int max_conn_count)
 390 {
 391         return drm_fbdev_cma_init_with_funcs(dev, preferred_bpp,
 392                                              max_conn_count,
 393                                              &drm_fb_cma_funcs);
 394 }
 395 EXPORT_SYMBOL_GPL(drm_fbdev_cma_init);
 396
 397 /**
 398  * drm_fbdev_cma_fini() - Free drm_fbdev_cma struct
 399  * @fbdev_cma: The drm_fbdev_cma struct
 400  */
 401 void drm_fbdev_cma_fini(struct drm_fbdev_cma *fbdev_cma)
 402 {
 403         drm_fb_helper_unregister_fbi(&fbdev_cma->fb_helper);
 404         if (fbdev_cma->fb_helper.fbdev)
 405                 drm_fbdev_cma_defio_fini(fbdev_cma->fb_helper.fbdev);
 406
 407         if (fbdev_cma->fb_helper.fb)
 408                 drm_framebuffer_remove(fbdev_cma->fb_helper.fb);
 409
 410         drm_fb_helper_fini(&fbdev_cma->fb_helper);
 411         kfree(fbdev_cma);
 412 }
 413 EXPORT_SYMBOL_GPL(drm_fbdev_cma_fini);
 414
 415 /**
 416  * drm_fbdev_cma_restore_mode() - Restores initial framebuffer mode
 417  * @fbdev_cma: The drm_fbdev_cma struct, may be NULL
 418  *
 419  * This function is usually called from the &drm_driver.lastclose callback.
 420  */
 421 void drm_fbdev_cma_restore_mode(struct drm_fbdev_cma *fbdev_cma)
 422 {
 423         if (fbdev_cma)
 424                 drm_fb_helper_restore_fbdev_mode_unlocked(&fbdev_cma->fb_helper);
 425 }
 426 EXPORT_SYMBOL_GPL(drm_fbdev_cma_restore_mode);
 427
 428 /**
 429  * drm_fbdev_cma_hotplug_event() - Poll for hotpulug events
 430  * @fbdev_cma: The drm_fbdev_cma struct, may be NULL
 431  *
 432  * This function is usually called from the &drm_mode_config.output_poll_changed
 433  * callback.
 434  */
 435 void drm_fbdev_cma_hotplug_event(struct drm_fbdev_cma *fbdev_cma)
 436 {
 437         if (fbdev_cma)
 438                 drm_fb_helper_hotplug_event(&fbdev_cma->fb_helper);
 439 }
 440 EXPORT_SYMBOL_GPL(drm_fbdev_cma_hotplug_event);
 441
 442 /**
 443  * drm_fbdev_cma_set_suspend - wrapper around drm_fb_helper_set_suspend
 444  * @fbdev_cma: The drm_fbdev_cma struct, may be NULL
 445  * @state: desired state, zero to resume, non-zero to suspend
 446  *
 447  * Calls drm_fb_helper_set_suspend, which is a wrapper around
 448  * fb_set_suspend implemented by fbdev core.
 449  */
 450 void drm_fbdev_cma_set_suspend(struct drm_fbdev_cma *fbdev_cma, bool state)
 451 {
 452         if (fbdev_cma)
 453                 drm_fb_helper_set_suspend(&fbdev_cma->fb_helper, state);
 454 }
 455 EXPORT_SYMBOL(drm_fbdev_cma_set_suspend);
 456
 457 /**
 458  * drm_fbdev_cma_set_suspend_unlocked - wrapper around
 459  *                                      drm_fb_helper_set_suspend_unlocked
 460  * @fbdev_cma: The drm_fbdev_cma struct, may be NULL
 461  * @state: desired state, zero to resume, non-zero to suspend
 462  *
 463  * Calls drm_fb_helper_set_suspend, which is a wrapper around
 464  * fb_set_suspend implemented by fbdev core.
 465  */
 466 void drm_fbdev_cma_set_suspend_unlocked(struct drm_fbdev_cma *fbdev_cma,
 467                                         bool state)
 468 {
 469         if (fbdev_cma)
 470                 drm_fb_helper_set_suspend_unlocked(&fbdev_cma->fb_helper,
 471                                                    state);
 472 }
 473 EXPORT_SYMBOL(drm_fbdev_cma_set_suspend_unlocked);