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 initialize 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 static 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
 203 /**
 204  * drm_fb_cma_debugfs_show() - Helper to list CMA framebuffer objects
 205  * in debugfs.
 206  */
 207 int drm_fb_cma_debugfs_show(struct seq_file *m, void *arg)
 208 {
 209         struct drm_info_node *node = (struct drm_info_node *) m->private;
 210         struct drm_device *dev = node->minor->dev;
 211         struct drm_framebuffer *fb;
 212
 213         mutex_lock(&dev->mode_config.fb_lock);
 214         drm_for_each_fb(fb, dev)
 215                 drm_fb_cma_describe(fb, m);
 216         mutex_unlock(&dev->mode_config.fb_lock);
 217
 218         return 0;
 219 }
 220 EXPORT_SYMBOL_GPL(drm_fb_cma_debugfs_show);
 221 #endif
 222
 223 static struct fb_ops drm_fbdev_cma_ops = {
 224         .owner          = THIS_MODULE,
 225         .fb_fillrect    = drm_fb_helper_sys_fillrect,
 226         .fb_copyarea    = drm_fb_helper_sys_copyarea,
 227         .fb_imageblit   = drm_fb_helper_sys_imageblit,
 228         .fb_check_var   = drm_fb_helper_check_var,
 229         .fb_set_par     = drm_fb_helper_set_par,
 230         .fb_blank       = drm_fb_helper_blank,
 231         .fb_pan_display = drm_fb_helper_pan_display,
 232         .fb_setcmap     = drm_fb_helper_setcmap,
 233 };
 234
 235 static int drm_fbdev_cma_create(struct drm_fb_helper *helper,
 236         struct drm_fb_helper_surface_size *sizes)
 237 {
 238         struct drm_fbdev_cma *fbdev_cma = to_fbdev_cma(helper);
 239         struct drm_mode_fb_cmd2 mode_cmd = { 0 };
 240         struct drm_device *dev = helper->dev;
 241         struct drm_gem_cma_object *obj;
 242         struct drm_framebuffer *fb;
 243         unsigned int bytes_per_pixel;
 244         unsigned long offset;
 245         struct fb_info *fbi;
 246         size_t size;
 247         int ret;
 248
 249         DRM_DEBUG_KMS("surface width(%d), height(%d) and bpp(%d)\n",
 250                         sizes->surface_width, sizes->surface_height,
 251                         sizes->surface_bpp);
 252
 253         bytes_per_pixel = DIV_ROUND_UP(sizes->surface_bpp, 8);
 254
 255         mode_cmd.width = sizes->surface_width;
 256         mode_cmd.height = sizes->surface_height;
 257         mode_cmd.pitches[0] = sizes->surface_width * bytes_per_pixel;
 258         mode_cmd.pixel_format = drm_mode_legacy_fb_format(sizes->surface_bpp,
 259                 sizes->surface_depth);
 260
 261         size = mode_cmd.pitches[0] * mode_cmd.height;
 262         obj = drm_gem_cma_create(dev, size);
 263         if (IS_ERR(obj))
 264                 return -ENOMEM;
 265
 266         fbi = drm_fb_helper_alloc_fbi(helper);
 267         if (IS_ERR(fbi)) {
 268                 ret = PTR_ERR(fbi);
 269                 goto err_drm_gem_cma_free_object;
 270         }
 271
 272         fbdev_cma->fb = drm_fb_cma_alloc(dev, &mode_cmd, &obj, 1);
 273         if (IS_ERR(fbdev_cma->fb)) {
 274                 dev_err(dev->dev, "Failed to allocate DRM framebuffer.\n");
 275                 ret = PTR_ERR(fbdev_cma->fb);
 276                 goto err_fb_info_destroy;
 277         }
 278
 279         fb = &fbdev_cma->fb->fb;
 280         helper->fb = fb;
 281
 282         fbi->par = helper;
 283         fbi->flags = FBINFO_FLAG_DEFAULT;
 284         fbi->fbops = &drm_fbdev_cma_ops;
 285
 286         drm_fb_helper_fill_fix(fbi, fb->pitches[0], fb->depth);
 287         drm_fb_helper_fill_var(fbi, helper, sizes->fb_width, sizes->fb_height);
 288
 289         offset = fbi->var.xoffset * bytes_per_pixel;
 290         offset += fbi->var.yoffset * fb->pitches[0];
 291
 292         dev->mode_config.fb_base = (resource_size_t)obj->paddr;
 293         fbi->screen_base = obj->vaddr + offset;
 294         fbi->fix.smem_start = (unsigned long)(obj->paddr + offset);
 295         fbi->screen_size = size;
 296         fbi->fix.smem_len = size;
 297
 298         return 0;
 299
 300 err_fb_info_destroy:
 301         drm_fb_helper_release_fbi(helper);
 302 err_drm_gem_cma_free_object:
 303         drm_gem_cma_free_object(&obj->base);
 304         return ret;
 305 }
 306
 307 static const struct drm_fb_helper_funcs drm_fb_cma_helper_funcs = {
 308         .fb_probe = drm_fbdev_cma_create,
 309 };
 310
 311 /**
 312  * drm_fbdev_cma_init() - Allocate and initializes a drm_fbdev_cma struct
 313  * @dev: DRM device
 314  * @preferred_bpp: Preferred bits per pixel for the device
 315  * @num_crtc: Number of CRTCs
 316  * @max_conn_count: Maximum number of connectors
 317  *
 318  * Returns a newly allocated drm_fbdev_cma struct or a ERR_PTR.
 319  */
 320 struct drm_fbdev_cma *drm_fbdev_cma_init(struct drm_device *dev,
 321         unsigned int preferred_bpp, unsigned int num_crtc,
 322         unsigned int max_conn_count)
 323 {
 324         struct drm_fbdev_cma *fbdev_cma;
 325         struct drm_fb_helper *helper;
 326         int ret;
 327
 328         fbdev_cma = kzalloc(sizeof(*fbdev_cma), GFP_KERNEL);
 329         if (!fbdev_cma) {
 330                 dev_err(dev->dev, "Failed to allocate drm fbdev.\n");
 331                 return ERR_PTR(-ENOMEM);
 332         }
 333
 334         helper = &fbdev_cma->fb_helper;
 335
 336         drm_fb_helper_prepare(dev, helper, &drm_fb_cma_helper_funcs);
 337
 338         ret = drm_fb_helper_init(dev, helper, num_crtc, max_conn_count);
 339         if (ret < 0) {
 340                 dev_err(dev->dev, "Failed to initialize drm fb helper.\n");
 341                 goto err_free;
 342         }
 343
 344         ret = drm_fb_helper_single_add_all_connectors(helper);
 345         if (ret < 0) {
 346                 dev_err(dev->dev, "Failed to add connectors.\n");
 347                 goto err_drm_fb_helper_fini;
 348
 349         }
 350
 351         /* disable all the possible outputs/crtcs before entering KMS mode */
 352         drm_helper_disable_unused_functions(dev);
 353
 354         ret = drm_fb_helper_initial_config(helper, preferred_bpp);
 355         if (ret < 0) {
 356                 dev_err(dev->dev, "Failed to set initial hw configuration.\n");
 357                 goto err_drm_fb_helper_fini;
 358         }
 359
 360         return fbdev_cma;
 361
 362 err_drm_fb_helper_fini:
 363         drm_fb_helper_fini(helper);
 364 err_free:
 365         kfree(fbdev_cma);
 366
 367         return ERR_PTR(ret);
 368 }
 369 EXPORT_SYMBOL_GPL(drm_fbdev_cma_init);
 370
 371 /**
 372  * drm_fbdev_cma_fini() - Free drm_fbdev_cma struct
 373  * @fbdev_cma: The drm_fbdev_cma struct
 374  */
 375 void drm_fbdev_cma_fini(struct drm_fbdev_cma *fbdev_cma)
 376 {
 377         drm_fb_helper_unregister_fbi(&fbdev_cma->fb_helper);
 378         drm_fb_helper_release_fbi(&fbdev_cma->fb_helper);
 379
 380         if (fbdev_cma->fb) {
 381                 drm_framebuffer_unregister_private(&fbdev_cma->fb->fb);
 382                 drm_fb_cma_destroy(&fbdev_cma->fb->fb);
 383         }
 384
 385         drm_fb_helper_fini(&fbdev_cma->fb_helper);
 386         kfree(fbdev_cma);
 387 }
 388 EXPORT_SYMBOL_GPL(drm_fbdev_cma_fini);
 389
 390 /**
 391  * drm_fbdev_cma_restore_mode() - Restores initial framebuffer mode
 392  * @fbdev_cma: The drm_fbdev_cma struct, may be NULL
 393  *
 394  * This function is usually called from the DRM drivers lastclose callback.
 395  */
 396 void drm_fbdev_cma_restore_mode(struct drm_fbdev_cma *fbdev_cma)
 397 {
 398         if (fbdev_cma)
 399                 drm_fb_helper_restore_fbdev_mode_unlocked(&fbdev_cma->fb_helper);
 400 }
 401 EXPORT_SYMBOL_GPL(drm_fbdev_cma_restore_mode);
 402
 403 /**
 404  * drm_fbdev_cma_hotplug_event() - Poll for hotpulug events
 405  * @fbdev_cma: The drm_fbdev_cma struct, may be NULL
 406  *
 407  * This function is usually called from the DRM drivers output_poll_changed
 408  * callback.
 409  */
 410 void drm_fbdev_cma_hotplug_event(struct drm_fbdev_cma *fbdev_cma)
 411 {
 412         if (fbdev_cma)
 413                 drm_fb_helper_hotplug_event(&fbdev_cma->fb_helper);
 414 }
 415 EXPORT_SYMBOL_GPL(drm_fbdev_cma_hotplug_event);