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         const struct drm_mode_fb_cmd2 *mode_cmd,
  78         struct drm_gem_cma_object **obj,
  79         unsigned int num_planes)
  80 {
  81         struct drm_fb_cma *fb_cma;
  82         int ret;
  83         int i;
  84
  85         fb_cma = kzalloc(sizeof(*fb_cma), GFP_KERNEL);
  86         if (!fb_cma)
  87                 return ERR_PTR(-ENOMEM);
  88
  89         drm_helper_mode_fill_fb_struct(&fb_cma->fb, mode_cmd);
  90
  91         for (i = 0; i < num_planes; i++)
  92                 fb_cma->obj[i] = obj[i];
  93
  94         ret = drm_framebuffer_init(dev, &fb_cma->fb, &drm_fb_cma_funcs);
  95         if (ret) {
  96                 dev_err(dev->dev, "Failed to initialize framebuffer: %d\n", ret);
  97                 kfree(fb_cma);
  98                 return ERR_PTR(ret);
  99         }
 100
 101         return fb_cma;
 102 }
 103
 104 /**
 105  * drm_fb_cma_create() - (struct drm_mode_config_funcs *)->fb_create callback function
 106  *
 107  * If your hardware has special alignment or pitch requirements these should be
 108  * checked before calling this function.
 109  */
 110 struct drm_framebuffer *drm_fb_cma_create(struct drm_device *dev,
 111         struct drm_file *file_priv, const struct drm_mode_fb_cmd2 *mode_cmd)
 112 {
 113         struct drm_fb_cma *fb_cma;
 114         struct drm_gem_cma_object *objs[4];
 115         struct drm_gem_object *obj;
 116         unsigned int hsub;
 117         unsigned int vsub;
 118         int ret;
 119         int i;
 120
 121         hsub = drm_format_horz_chroma_subsampling(mode_cmd->pixel_format);
 122         vsub = drm_format_vert_chroma_subsampling(mode_cmd->pixel_format);
 123
 124         for (i = 0; i < drm_format_num_planes(mode_cmd->pixel_format); i++) {
 125                 unsigned int width = mode_cmd->width / (i ? hsub : 1);
 126                 unsigned int height = mode_cmd->height / (i ? vsub : 1);
 127                 unsigned int min_size;
 128
 129                 obj = drm_gem_object_lookup(dev, file_priv, mode_cmd->handles[i]);
 130                 if (!obj) {
 131                         dev_err(dev->dev, "Failed to lookup GEM object\n");
 132                         ret = -ENXIO;
 133                         goto err_gem_object_unreference;
 134                 }
 135
 136                 min_size = (height - 1) * mode_cmd->pitches[i]
 137                          + width * drm_format_plane_cpp(mode_cmd->pixel_format, i)
 138                          + mode_cmd->offsets[i];
 139
 140                 if (obj->size < min_size) {
 141                         drm_gem_object_unreference_unlocked(obj);
 142                         ret = -EINVAL;
 143                         goto err_gem_object_unreference;
 144                 }
 145                 objs[i] = to_drm_gem_cma_obj(obj);
 146         }
 147
 148         fb_cma = drm_fb_cma_alloc(dev, mode_cmd, objs, i);
 149         if (IS_ERR(fb_cma)) {
 150                 ret = PTR_ERR(fb_cma);
 151                 goto err_gem_object_unreference;
 152         }
 153
 154         return &fb_cma->fb;
 155
 156 err_gem_object_unreference:
 157         for (i--; i >= 0; i--)
 158                 drm_gem_object_unreference_unlocked(&objs[i]->base);
 159         return ERR_PTR(ret);
 160 }
 161 EXPORT_SYMBOL_GPL(drm_fb_cma_create);
 162
 163 /**
 164  * drm_fb_cma_get_gem_obj() - Get CMA GEM object for framebuffer
 165  * @fb: The framebuffer
 166  * @plane: Which plane
 167  *
 168  * Return the CMA GEM object for given framebuffer.
 169  *
 170  * This function will usually be called from the CRTC callback functions.
 171  */
 172 struct drm_gem_cma_object *drm_fb_cma_get_gem_obj(struct drm_framebuffer *fb,
 173         unsigned int plane)
 174 {
 175         struct drm_fb_cma *fb_cma = to_fb_cma(fb);
 176
 177         if (plane >= 4)
 178                 return NULL;
 179
 180         return fb_cma->obj[plane];
 181 }
 182 EXPORT_SYMBOL_GPL(drm_fb_cma_get_gem_obj);
 183
 184 #ifdef CONFIG_DEBUG_FS
 185 /*
 186  * drm_fb_cma_describe() - Helper to dump information about a single
 187  * CMA framebuffer object
 188  */
 189 static void drm_fb_cma_describe(struct drm_framebuffer *fb, struct seq_file *m)
 190 {
 191         struct drm_fb_cma *fb_cma = to_fb_cma(fb);
 192         int i, n = drm_format_num_planes(fb->pixel_format);
 193
 194         seq_printf(m, "fb: %dx%d@%4.4s\n", fb->width, fb->height,
 195                         (char *)&fb->pixel_format);
 196
 197         for (i = 0; i < n; i++) {
 198                 seq_printf(m, "   %d: offset=%d pitch=%d, obj: ",
 199                                 i, fb->offsets[i], fb->pitches[i]);
 200                 drm_gem_cma_describe(fb_cma->obj[i], m);
 201         }
 202 }
 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
 214         mutex_lock(&dev->mode_config.fb_lock);
 215         drm_for_each_fb(fb, dev)
 216                 drm_fb_cma_describe(fb, m);
 217         mutex_unlock(&dev->mode_config.fb_lock);
 218
 219         return 0;
 220 }
 221 EXPORT_SYMBOL_GPL(drm_fb_cma_debugfs_show);
 222 #endif
 223
 224 static struct fb_ops drm_fbdev_cma_ops = {
 225         .owner          = THIS_MODULE,
 226         .fb_fillrect    = drm_fb_helper_sys_fillrect,
 227         .fb_copyarea    = drm_fb_helper_sys_copyarea,
 228         .fb_imageblit   = drm_fb_helper_sys_imageblit,
 229         .fb_check_var   = drm_fb_helper_check_var,
 230         .fb_set_par     = drm_fb_helper_set_par,
 231         .fb_blank       = drm_fb_helper_blank,
 232         .fb_pan_display = drm_fb_helper_pan_display,
 233         .fb_setcmap     = drm_fb_helper_setcmap,
 234 };
 235
 236 static int drm_fbdev_cma_create(struct drm_fb_helper *helper,
 237         struct drm_fb_helper_surface_size *sizes)
 238 {
 239         struct drm_fbdev_cma *fbdev_cma = to_fbdev_cma(helper);
 240         struct drm_mode_fb_cmd2 mode_cmd = { 0 };
 241         struct drm_device *dev = helper->dev;
 242         struct drm_gem_cma_object *obj;
 243         struct drm_framebuffer *fb;
 244         unsigned int bytes_per_pixel;
 245         unsigned long offset;
 246         struct fb_info *fbi;
 247         size_t size;
 248         int ret;
 249
 250         DRM_DEBUG_KMS("surface width(%d), height(%d) and bpp(%d)\n",
 251                         sizes->surface_width, sizes->surface_height,
 252                         sizes->surface_bpp);
 253
 254         bytes_per_pixel = DIV_ROUND_UP(sizes->surface_bpp, 8);
 255
 256         mode_cmd.width = sizes->surface_width;
 257         mode_cmd.height = sizes->surface_height;
 258         mode_cmd.pitches[0] = sizes->surface_width * bytes_per_pixel;
 259         mode_cmd.pixel_format = drm_mode_legacy_fb_format(sizes->surface_bpp,
 260                 sizes->surface_depth);
 261
 262         size = mode_cmd.pitches[0] * mode_cmd.height;
 263         obj = drm_gem_cma_create(dev, size);
 264         if (IS_ERR(obj))
 265                 return -ENOMEM;
 266
 267         fbi = drm_fb_helper_alloc_fbi(helper);
 268         if (IS_ERR(fbi)) {
 269                 ret = PTR_ERR(fbi);
 270                 goto err_gem_free_object;
 271         }
 272
 273         fbdev_cma->fb = drm_fb_cma_alloc(dev, &mode_cmd, &obj, 1);
 274         if (IS_ERR(fbdev_cma->fb)) {
 275                 dev_err(dev->dev, "Failed to allocate DRM framebuffer.\n");
 276                 ret = PTR_ERR(fbdev_cma->fb);
 277                 goto err_fb_info_destroy;
 278         }
 279
 280         fb = &fbdev_cma->fb->fb;
 281         helper->fb = fb;
 282
 283         fbi->par = helper;
 284         fbi->flags = FBINFO_FLAG_DEFAULT;
 285         fbi->fbops = &drm_fbdev_cma_ops;
 286
 287         drm_fb_helper_fill_fix(fbi, fb->pitches[0], fb->depth);
 288         drm_fb_helper_fill_var(fbi, helper, sizes->fb_width, sizes->fb_height);
 289
 290         offset = fbi->var.xoffset * bytes_per_pixel;
 291         offset += fbi->var.yoffset * fb->pitches[0];
 292
 293         dev->mode_config.fb_base = (resource_size_t)obj->paddr;
 294         fbi->screen_base = obj->vaddr + offset;
 295         fbi->fix.smem_start = (unsigned long)(obj->paddr + offset);
 296         fbi->screen_size = size;
 297         fbi->fix.smem_len = size;
 298
 299         return 0;
 300
 301 err_fb_info_destroy:
 302         drm_fb_helper_release_fbi(helper);
 303 err_gem_free_object:
 304         dev->driver->gem_free_object(&obj->base);
 305         return ret;
 306 }
 307
 308 static const struct drm_fb_helper_funcs drm_fb_cma_helper_funcs = {
 309         .fb_probe = drm_fbdev_cma_create,
 310 };
 311
 312 /**
 313  * drm_fbdev_cma_init() - Allocate and initializes a drm_fbdev_cma struct
 314  * @dev: DRM device
 315  * @preferred_bpp: Preferred bits per pixel for the device
 316  * @num_crtc: Number of CRTCs
 317  * @max_conn_count: Maximum number of connectors
 318  *
 319  * Returns a newly allocated drm_fbdev_cma struct or a ERR_PTR.
 320  */
 321 struct drm_fbdev_cma *drm_fbdev_cma_init(struct drm_device *dev,
 322         unsigned int preferred_bpp, unsigned int num_crtc,
 323         unsigned int max_conn_count)
 324 {
 325         struct drm_fbdev_cma *fbdev_cma;
 326         struct drm_fb_helper *helper;
 327         int ret;
 328
 329         fbdev_cma = kzalloc(sizeof(*fbdev_cma), GFP_KERNEL);
 330         if (!fbdev_cma) {
 331                 dev_err(dev->dev, "Failed to allocate drm fbdev.\n");
 332                 return ERR_PTR(-ENOMEM);
 333         }
 334
 335         helper = &fbdev_cma->fb_helper;
 336
 337         drm_fb_helper_prepare(dev, helper, &drm_fb_cma_helper_funcs);
 338
 339         ret = drm_fb_helper_init(dev, helper, num_crtc, max_conn_count);
 340         if (ret < 0) {
 341                 dev_err(dev->dev, "Failed to initialize drm fb helper.\n");
 342                 goto err_free;
 343         }
 344
 345         ret = drm_fb_helper_single_add_all_connectors(helper);
 346         if (ret < 0) {
 347                 dev_err(dev->dev, "Failed to add connectors.\n");
 348                 goto err_drm_fb_helper_fini;
 349
 350         }
 351
 352         ret = drm_fb_helper_initial_config(helper, preferred_bpp);
 353         if (ret < 0) {
 354                 dev_err(dev->dev, "Failed to set initial hw configuration.\n");
 355                 goto err_drm_fb_helper_fini;
 356         }
 357
 358         return fbdev_cma;
 359
 360 err_drm_fb_helper_fini:
 361         drm_fb_helper_fini(helper);
 362 err_free:
 363         kfree(fbdev_cma);
 364
 365         return ERR_PTR(ret);
 366 }
 367 EXPORT_SYMBOL_GPL(drm_fbdev_cma_init);
 368
 369 /**
 370  * drm_fbdev_cma_fini() - Free drm_fbdev_cma struct
 371  * @fbdev_cma: The drm_fbdev_cma struct
 372  */
 373 void drm_fbdev_cma_fini(struct drm_fbdev_cma *fbdev_cma)
 374 {
 375         drm_fb_helper_unregister_fbi(&fbdev_cma->fb_helper);
 376         drm_fb_helper_release_fbi(&fbdev_cma->fb_helper);
 377
 378         if (fbdev_cma->fb) {
 379                 drm_framebuffer_unregister_private(&fbdev_cma->fb->fb);
 380                 drm_fb_cma_destroy(&fbdev_cma->fb->fb);
 381         }
 382
 383         drm_fb_helper_fini(&fbdev_cma->fb_helper);
 384         kfree(fbdev_cma);
 385 }
 386 EXPORT_SYMBOL_GPL(drm_fbdev_cma_fini);
 387
 388 /**
 389  * drm_fbdev_cma_restore_mode() - Restores initial framebuffer mode
 390  * @fbdev_cma: The drm_fbdev_cma struct, may be NULL
 391  *
 392  * This function is usually called from the DRM drivers lastclose callback.
 393  */
 394 void drm_fbdev_cma_restore_mode(struct drm_fbdev_cma *fbdev_cma)
 395 {
 396         if (fbdev_cma)
 397                 drm_fb_helper_restore_fbdev_mode_unlocked(&fbdev_cma->fb_helper);
 398 }
 399 EXPORT_SYMBOL_GPL(drm_fbdev_cma_restore_mode);
 400
 401 /**
 402  * drm_fbdev_cma_hotplug_event() - Poll for hotpulug events
 403  * @fbdev_cma: The drm_fbdev_cma struct, may be NULL
 404  *
 405  * This function is usually called from the DRM drivers output_poll_changed
 406  * callback.
 407  */
 408 void drm_fbdev_cma_hotplug_event(struct drm_fbdev_cma *fbdev_cma)
 409 {
 410         if (fbdev_cma)
 411                 drm_fb_helper_hotplug_event(&fbdev_cma->fb_helper);
 412 }
 413 EXPORT_SYMBOL_GPL(drm_fbdev_cma_hotplug_event);