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 <lars@metafoo.de>
   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_crtc.h>
  22 #include <drm/drm_fb_helper.h>
  23 #include <drm/drm_crtc_helper.h>
  24 #include <drm/drm_gem_cma_helper.h>
  25 #include <drm/drm_fb_cma_helper.h>
  26 #include <linux/module.h>
  27
  28 struct drm_fb_cma {
  29         struct drm_framebuffer          fb;
  30         struct drm_gem_cma_object       *obj[4];
  31 };
  32
  33 struct drm_fbdev_cma {
  34         struct drm_fb_helper    fb_helper;
  35         struct drm_fb_cma       *fb;
  36 };
  37
  38 static inline struct drm_fbdev_cma *to_fbdev_cma(struct drm_fb_helper *helper)
  39 {
  40         return container_of(helper, struct drm_fbdev_cma, fb_helper);
  41 }
  42
  43 static inline struct drm_fb_cma *to_fb_cma(struct drm_framebuffer *fb)
  44 {
  45         return container_of(fb, struct drm_fb_cma, fb);
  46 }
  47
  48 static void drm_fb_cma_destroy(struct drm_framebuffer *fb)
  49 {
  50         struct drm_fb_cma *fb_cma = to_fb_cma(fb);
  51         int i;
  52
  53         for (i = 0; i < 4; i++) {
  54                 if (fb_cma->obj[i])
  55                         drm_gem_object_unreference_unlocked(&fb_cma->obj[i]->base);
  56         }
  57
  58         drm_framebuffer_cleanup(fb);
  59         kfree(fb_cma);
  60 }
  61
  62 static int drm_fb_cma_create_handle(struct drm_framebuffer *fb,
  63         struct drm_file *file_priv, unsigned int *handle)
  64 {
  65         struct drm_fb_cma *fb_cma = to_fb_cma(fb);
  66
  67         return drm_gem_handle_create(file_priv,
  68                         &fb_cma->obj[0]->base, handle);
  69 }
  70
  71 static struct drm_framebuffer_funcs drm_fb_cma_funcs = {
  72         .destroy        = drm_fb_cma_destroy,
  73         .create_handle  = drm_fb_cma_create_handle,
  74 };
  75
  76 static struct drm_fb_cma *drm_fb_cma_alloc(struct drm_device *dev,
  77         struct drm_mode_fb_cmd2 *mode_cmd, struct drm_gem_cma_object **obj,
  78         unsigned int num_planes)
  79 {
  80         struct drm_fb_cma *fb_cma;
  81         int ret;
  82         int i;
  83
  84         fb_cma = kzalloc(sizeof(*fb_cma), GFP_KERNEL);
  85         if (!fb_cma)
  86                 return ERR_PTR(-ENOMEM);
  87
  88         drm_helper_mode_fill_fb_struct(&fb_cma->fb, mode_cmd);
  89
  90         for (i = 0; i < num_planes; i++)
  91                 fb_cma->obj[i] = obj[i];
  92
  93         ret = drm_framebuffer_init(dev, &fb_cma->fb, &drm_fb_cma_funcs);
  94         if (ret) {
  95                 dev_err(dev->dev, "Failed to initalize framebuffer: %d\n", ret);
  96                 kfree(fb_cma);
  97                 return ERR_PTR(ret);
  98         }
  99
 100         return fb_cma;
 101 }
 102
 103 /**
 104  * drm_fb_cma_create() - (struct drm_mode_config_funcs *)->fb_create callback function
 105  *
 106  * If your hardware has special alignment or pitch requirements these should be
 107  * checked before calling this function.
 108  */
 109 struct drm_framebuffer *drm_fb_cma_create(struct drm_device *dev,
 110         struct drm_file *file_priv, struct drm_mode_fb_cmd2 *mode_cmd)
 111 {
 112         struct drm_fb_cma *fb_cma;
 113         struct drm_gem_cma_object *objs[4];
 114         struct drm_gem_object *obj;
 115         unsigned int hsub;
 116         unsigned int vsub;
 117         int ret;
 118         int i;
 119
 120         hsub = drm_format_horz_chroma_subsampling(mode_cmd->pixel_format);
 121         vsub = drm_format_vert_chroma_subsampling(mode_cmd->pixel_format);
 122
 123         for (i = 0; i < drm_format_num_planes(mode_cmd->pixel_format); i++) {
 124                 unsigned int width = mode_cmd->width / (i ? hsub : 1);
 125                 unsigned int height = mode_cmd->height / (i ? vsub : 1);
 126                 unsigned int min_size;
 127
 128                 obj = drm_gem_object_lookup(dev, file_priv, mode_cmd->handles[i]);
 129                 if (!obj) {
 130                         dev_err(dev->dev, "Failed to lookup GEM object\n");
 131                         ret = -ENXIO;
 132                         goto err_gem_object_unreference;
 133                 }
 134
 135                 min_size = (height - 1) * mode_cmd->pitches[i]
 136                          + width * drm_format_plane_cpp(mode_cmd->pixel_format, i)
 137                          + mode_cmd->offsets[i];
 138
 139                 if (obj->size < min_size) {
 140                         drm_gem_object_unreference_unlocked(obj);
 141                         ret = -EINVAL;
 142                         goto err_gem_object_unreference;
 143                 }
 144                 objs[i] = to_drm_gem_cma_obj(obj);
 145         }
 146
 147         fb_cma = drm_fb_cma_alloc(dev, mode_cmd, objs, i);
 148         if (IS_ERR(fb_cma)) {
 149                 ret = PTR_ERR(fb_cma);
 150                 goto err_gem_object_unreference;
 151         }
 152
 153         return &fb_cma->fb;
 154
 155 err_gem_object_unreference:
 156         for (i--; i >= 0; i--)
 157                 drm_gem_object_unreference_unlocked(&objs[i]->base);
 158         return ERR_PTR(ret);
 159 }
 160 EXPORT_SYMBOL_GPL(drm_fb_cma_create);
 161
 162 /**
 163  * drm_fb_cma_get_gem_obj() - Get CMA GEM object for framebuffer
 164  * @fb: The framebuffer
 165  * @plane: Which plane
 166  *
 167  * Return the CMA GEM object for given framebuffer.
 168  *
 169  * This function will usually be called from the CRTC callback functions.
 170  */
 171 struct drm_gem_cma_object *drm_fb_cma_get_gem_obj(struct drm_framebuffer *fb,
 172         unsigned int plane)
 173 {
 174         struct drm_fb_cma *fb_cma = to_fb_cma(fb);
 175
 176         if (plane >= 4)
 177                 return NULL;
 178
 179         return fb_cma->obj[plane];
 180 }
 181 EXPORT_SYMBOL_GPL(drm_fb_cma_get_gem_obj);
 182
 183 #ifdef CONFIG_DEBUG_FS
 184 /**
 185  * drm_fb_cma_describe() - Helper to dump information about a single
 186  * CMA framebuffer object
 187  */
 188 void drm_fb_cma_describe(struct drm_framebuffer *fb, struct seq_file *m)
 189 {
 190         struct drm_fb_cma *fb_cma = to_fb_cma(fb);
 191         int i, n = drm_format_num_planes(fb->pixel_format);
 192
 193         seq_printf(m, "fb: %dx%d@%4.4s\n", fb->width, fb->height,
 194                         (char *)&fb->pixel_format);
 195
 196         for (i = 0; i < n; i++) {
 197                 seq_printf(m, "   %d: offset=%d pitch=%d, obj: ",
 198                                 i, fb->offsets[i], fb->pitches[i]);
 199                 drm_gem_cma_describe(fb_cma->obj[i], m);
 200         }
 201 }
 202 EXPORT_SYMBOL_GPL(drm_fb_cma_describe);
 203
 204 /**
 205  * drm_fb_cma_debugfs_show() - Helper to list CMA framebuffer objects
 206  * in debugfs.
 207  */
 208 int drm_fb_cma_debugfs_show(struct seq_file *m, void *arg)
 209 {
 210         struct drm_info_node *node = (struct drm_info_node *) m->private;
 211         struct drm_device *dev = node->minor->dev;
 212         struct drm_framebuffer *fb;
 213         int ret;
 214
 215         ret = mutex_lock_interruptible(&dev->mode_config.mutex);
 216         if (ret)
 217                 return ret;
 218
 219         ret = mutex_lock_interruptible(&dev->struct_mutex);
 220         if (ret) {
 221                 mutex_unlock(&dev->mode_config.mutex);
 222                 return ret;
 223         }
 224
 225         list_for_each_entry(fb, &dev->mode_config.fb_list, head)
 226                 drm_fb_cma_describe(fb, m);
 227
 228         mutex_unlock(&dev->struct_mutex);
 229         mutex_unlock(&dev->mode_config.mutex);
 230
 231         return 0;
 232 }
 233 EXPORT_SYMBOL_GPL(drm_fb_cma_debugfs_show);
 234 #endif
 235
 236 static struct fb_ops drm_fbdev_cma_ops = {
 237         .owner          = THIS_MODULE,
 238         .fb_fillrect    = sys_fillrect,
 239         .fb_copyarea    = sys_copyarea,
 240         .fb_imageblit   = sys_imageblit,
 241         .fb_check_var   = drm_fb_helper_check_var,
 242         .fb_set_par     = drm_fb_helper_set_par,
 243         .fb_blank       = drm_fb_helper_blank,
 244         .fb_pan_display = drm_fb_helper_pan_display,
 245         .fb_setcmap     = drm_fb_helper_setcmap,
 246 };
 247
 248 static int drm_fbdev_cma_create(struct drm_fb_helper *helper,
 249         struct drm_fb_helper_surface_size *sizes)
 250 {
 251         struct drm_fbdev_cma *fbdev_cma = to_fbdev_cma(helper);
 252         struct drm_mode_fb_cmd2 mode_cmd = { 0 };
 253         struct drm_device *dev = helper->dev;
 254         struct drm_gem_cma_object *obj;
 255         struct drm_framebuffer *fb;
 256         unsigned int bytes_per_pixel;
 257         unsigned long offset;
 258         struct fb_info *fbi;
 259         size_t size;
 260         int ret;
 261
 262         DRM_DEBUG_KMS("surface width(%d), height(%d) and bpp(%d)\n",
 263                         sizes->surface_width, sizes->surface_height,
 264                         sizes->surface_bpp);
 265
 266         bytes_per_pixel = DIV_ROUND_UP(sizes->surface_bpp, 8);
 267
 268         mode_cmd.width = sizes->surface_width;
 269         mode_cmd.height = sizes->surface_height;
 270         mode_cmd.pitches[0] = sizes->surface_width * bytes_per_pixel;
 271         mode_cmd.pixel_format = drm_mode_legacy_fb_format(sizes->surface_bpp,
 272                 sizes->surface_depth);
 273
 274         size = mode_cmd.pitches[0] * mode_cmd.height;
 275         obj = drm_gem_cma_create(dev, size);
 276         if (IS_ERR(obj))
 277                 return -ENOMEM;
 278
 279         fbi = framebuffer_alloc(0, dev->dev);
 280         if (!fbi) {
 281                 dev_err(dev->dev, "Failed to allocate framebuffer info.\n");
 282                 ret = -ENOMEM;
 283                 goto err_drm_gem_cma_free_object;
 284         }
 285
 286         fbdev_cma->fb = drm_fb_cma_alloc(dev, &mode_cmd, &obj, 1);
 287         if (IS_ERR(fbdev_cma->fb)) {
 288                 dev_err(dev->dev, "Failed to allocate DRM framebuffer.\n");
 289                 ret = PTR_ERR(fbdev_cma->fb);
 290                 goto err_framebuffer_release;
 291         }
 292
 293         fb = &fbdev_cma->fb->fb;
 294         helper->fb = fb;
 295         helper->fbdev = fbi;
 296
 297         fbi->par = helper;
 298         fbi->flags = FBINFO_FLAG_DEFAULT;
 299         fbi->fbops = &drm_fbdev_cma_ops;
 300
 301         ret = fb_alloc_cmap(&fbi->cmap, 256, 0);
 302         if (ret) {
 303                 dev_err(dev->dev, "Failed to allocate color map.\n");
 304                 goto err_drm_fb_cma_destroy;
 305         }
 306
 307         drm_fb_helper_fill_fix(fbi, fb->pitches[0], fb->depth);
 308         drm_fb_helper_fill_var(fbi, helper, fb->width, fb->height);
 309
 310         offset = fbi->var.xoffset * bytes_per_pixel;
 311         offset += fbi->var.yoffset * fb->pitches[0];
 312
 313         dev->mode_config.fb_base = (resource_size_t)obj->paddr;
 314         fbi->screen_base = obj->vaddr + offset;
 315         fbi->fix.smem_start = (unsigned long)(obj->paddr + offset);
 316         fbi->screen_size = size;
 317         fbi->fix.smem_len = size;
 318
 319         return 0;
 320
 321 err_drm_fb_cma_destroy:
 322         drm_framebuffer_unregister_private(fb);
 323         drm_fb_cma_destroy(fb);
 324 err_framebuffer_release:
 325         framebuffer_release(fbi);
 326 err_drm_gem_cma_free_object:
 327         drm_gem_cma_free_object(&obj->base);
 328         return ret;
 329 }
 330
 331 static struct drm_fb_helper_funcs drm_fb_cma_helper_funcs = {
 332         .fb_probe = drm_fbdev_cma_create,
 333 };
 334
 335 /**
 336  * drm_fbdev_cma_init() - Allocate and initializes a drm_fbdev_cma struct
 337  * @dev: DRM device
 338  * @preferred_bpp: Preferred bits per pixel for the device
 339  * @num_crtc: Number of CRTCs
 340  * @max_conn_count: Maximum number of connectors
 341  *
 342  * Returns a newly allocated drm_fbdev_cma struct or a ERR_PTR.
 343  */
 344 struct drm_fbdev_cma *drm_fbdev_cma_init(struct drm_device *dev,
 345         unsigned int preferred_bpp, unsigned int num_crtc,
 346         unsigned int max_conn_count)
 347 {
 348         struct drm_fbdev_cma *fbdev_cma;
 349         struct drm_fb_helper *helper;
 350         int ret;
 351
 352         fbdev_cma = kzalloc(sizeof(*fbdev_cma), GFP_KERNEL);
 353         if (!fbdev_cma) {
 354                 dev_err(dev->dev, "Failed to allocate drm fbdev.\n");
 355                 return ERR_PTR(-ENOMEM);
 356         }
 357
 358         fbdev_cma->fb_helper.funcs = &drm_fb_cma_helper_funcs;
 359         helper = &fbdev_cma->fb_helper;
 360
 361         ret = drm_fb_helper_init(dev, helper, num_crtc, max_conn_count);
 362         if (ret < 0) {
 363                 dev_err(dev->dev, "Failed to initialize drm fb helper.\n");
 364                 goto err_free;
 365         }
 366
 367         ret = drm_fb_helper_single_add_all_connectors(helper);
 368         if (ret < 0) {
 369                 dev_err(dev->dev, "Failed to add connectors.\n");
 370                 goto err_drm_fb_helper_fini;
 371
 372         }
 373
 374         /* disable all the possible outputs/crtcs before entering KMS mode */
 375         drm_helper_disable_unused_functions(dev);
 376
 377         ret = drm_fb_helper_initial_config(helper, preferred_bpp);
 378         if (ret < 0) {
 379                 dev_err(dev->dev, "Failed to set inital hw configuration.\n");
 380                 goto err_drm_fb_helper_fini;
 381         }
 382
 383         return fbdev_cma;
 384
 385 err_drm_fb_helper_fini:
 386         drm_fb_helper_fini(helper);
 387 err_free:
 388         kfree(fbdev_cma);
 389
 390         return ERR_PTR(ret);
 391 }
 392 EXPORT_SYMBOL_GPL(drm_fbdev_cma_init);
 393
 394 /**
 395  * drm_fbdev_cma_fini() - Free drm_fbdev_cma struct
 396  * @fbdev_cma: The drm_fbdev_cma struct
 397  */
 398 void drm_fbdev_cma_fini(struct drm_fbdev_cma *fbdev_cma)
 399 {
 400         if (fbdev_cma->fb_helper.fbdev) {
 401                 struct fb_info *info;
 402                 int ret;
 403
 404                 info = fbdev_cma->fb_helper.fbdev;
 405                 ret = unregister_framebuffer(info);
 406                 if (ret < 0)
 407                         DRM_DEBUG_KMS("failed unregister_framebuffer()\n");
 408
 409                 if (info->cmap.len)
 410                         fb_dealloc_cmap(&info->cmap);
 411
 412                 framebuffer_release(info);
 413         }
 414
 415         if (fbdev_cma->fb) {
 416                 drm_framebuffer_unregister_private(&fbdev_cma->fb->fb);
 417                 drm_fb_cma_destroy(&fbdev_cma->fb->fb);
 418         }
 419
 420         drm_fb_helper_fini(&fbdev_cma->fb_helper);
 421         kfree(fbdev_cma);
 422 }
 423 EXPORT_SYMBOL_GPL(drm_fbdev_cma_fini);
 424
 425 /**
 426  * drm_fbdev_cma_restore_mode() - Restores initial framebuffer mode
 427  * @fbdev_cma: The drm_fbdev_cma struct, may be NULL
 428  *
 429  * This function is usually called from the DRM drivers lastclose callback.
 430  */
 431 void drm_fbdev_cma_restore_mode(struct drm_fbdev_cma *fbdev_cma)
 432 {
 433         if (fbdev_cma) {
 434                 struct drm_device *dev = fbdev_cma->fb_helper.dev;
 435
 436                 drm_modeset_lock_all(dev);
 437                 drm_fb_helper_restore_fbdev_mode(&fbdev_cma->fb_helper);
 438                 drm_modeset_unlock_all(dev);
 439         }
 440 }
 441 EXPORT_SYMBOL_GPL(drm_fbdev_cma_restore_mode);
 442
 443 /**
 444  * drm_fbdev_cma_hotplug_event() - Poll for hotpulug events
 445  * @fbdev_cma: The drm_fbdev_cma struct, may be NULL
 446  *
 447  * This function is usually called from the DRM drivers output_poll_changed
 448  * callback.
 449  */
 450 void drm_fbdev_cma_hotplug_event(struct drm_fbdev_cma *fbdev_cma)
 451 {
 452         if (fbdev_cma)
 453                 drm_fb_helper_hotplug_event(&fbdev_cma->fb_helper);
 454 }
 455 EXPORT_SYMBOL_GPL(drm_fbdev_cma_hotplug_event);