drm_fb_cma_helper.c 16 KB

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  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. #include <drm/drmP.h>
  20. #include <drm/drm_crtc.h>
  21. #include <drm/drm_fb_helper.h>
  22. #include <drm/drm_crtc_helper.h>
  23. #include <drm/drm_gem_cma_helper.h>
  24. #include <drm/drm_fb_cma_helper.h>
  25. #include <linux/module.h>
  26. #define DEFAULT_FBDEFIO_DELAY_MS 50
  27. struct drm_fb_cma {
  28. struct drm_framebuffer fb;
  29. struct drm_gem_cma_object *obj[4];
  30. };
  31. struct drm_fbdev_cma {
  32. struct drm_fb_helper fb_helper;
  33. struct drm_fb_cma *fb;
  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_fb_cma_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
  47. * will be set up automatically. 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_fbdev_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_fbdev_fb_funcs = {
  64. * .destroy = drm_fb_cma_destroy,
  65. * .create_handle = drm_fb_cma_create_handle,
  66. * .dirty = driver_fbdev_fb_dirty,
  67. * };
  68. *
  69. * static int driver_fbdev_create(struct drm_fb_helper *helper,
  70. * struct drm_fb_helper_surface_size *sizes)
  71. * {
  72. * return drm_fbdev_cma_create_with_funcs(helper, sizes,
  73. * &driver_fbdev_fb_funcs);
  74. * }
  75. *
  76. * static const struct drm_fb_helper_funcs driver_fb_helper_funcs = {
  77. * .fb_probe = driver_fbdev_create,
  78. * };
  79. *
  80. * Initialize:
  81. * fbdev = drm_fbdev_cma_init_with_funcs(dev, 16,
  82. * dev->mode_config.num_crtc,
  83. * dev->mode_config.num_connector,
  84. * &driver_fb_helper_funcs);
  85. *
  86. */
  87. static inline struct drm_fbdev_cma *to_fbdev_cma(struct drm_fb_helper *helper)
  88. {
  89. return container_of(helper, struct drm_fbdev_cma, fb_helper);
  90. }
  91. static inline struct drm_fb_cma *to_fb_cma(struct drm_framebuffer *fb)
  92. {
  93. return container_of(fb, struct drm_fb_cma, fb);
  94. }
  95. void drm_fb_cma_destroy(struct drm_framebuffer *fb)
  96. {
  97. struct drm_fb_cma *fb_cma = to_fb_cma(fb);
  98. int i;
  99. for (i = 0; i < 4; i++) {
  100. if (fb_cma->obj[i])
  101. drm_gem_object_unreference_unlocked(&fb_cma->obj[i]->base);
  102. }
  103. drm_framebuffer_cleanup(fb);
  104. kfree(fb_cma);
  105. }
  106. EXPORT_SYMBOL(drm_fb_cma_destroy);
  107. int drm_fb_cma_create_handle(struct drm_framebuffer *fb,
  108. struct drm_file *file_priv, unsigned int *handle)
  109. {
  110. struct drm_fb_cma *fb_cma = to_fb_cma(fb);
  111. return drm_gem_handle_create(file_priv,
  112. &fb_cma->obj[0]->base, handle);
  113. }
  114. EXPORT_SYMBOL(drm_fb_cma_create_handle);
  115. static struct drm_framebuffer_funcs drm_fb_cma_funcs = {
  116. .destroy = drm_fb_cma_destroy,
  117. .create_handle = drm_fb_cma_create_handle,
  118. };
  119. static struct drm_fb_cma *drm_fb_cma_alloc(struct drm_device *dev,
  120. const struct drm_mode_fb_cmd2 *mode_cmd,
  121. struct drm_gem_cma_object **obj,
  122. unsigned int num_planes, struct drm_framebuffer_funcs *funcs)
  123. {
  124. struct drm_fb_cma *fb_cma;
  125. int ret;
  126. int i;
  127. fb_cma = kzalloc(sizeof(*fb_cma), GFP_KERNEL);
  128. if (!fb_cma)
  129. return ERR_PTR(-ENOMEM);
  130. drm_helper_mode_fill_fb_struct(&fb_cma->fb, mode_cmd);
  131. for (i = 0; i < num_planes; i++)
  132. fb_cma->obj[i] = obj[i];
  133. ret = drm_framebuffer_init(dev, &fb_cma->fb, funcs);
  134. if (ret) {
  135. dev_err(dev->dev, "Failed to initialize framebuffer: %d\n", ret);
  136. kfree(fb_cma);
  137. return ERR_PTR(ret);
  138. }
  139. return fb_cma;
  140. }
  141. /**
  142. * drm_fb_cma_create() - (struct drm_mode_config_funcs *)->fb_create callback function
  143. *
  144. * If your hardware has special alignment or pitch requirements these should be
  145. * checked before calling this function.
  146. */
  147. struct drm_framebuffer *drm_fb_cma_create(struct drm_device *dev,
  148. struct drm_file *file_priv, const struct drm_mode_fb_cmd2 *mode_cmd)
  149. {
  150. struct drm_fb_cma *fb_cma;
  151. struct drm_gem_cma_object *objs[4];
  152. struct drm_gem_object *obj;
  153. unsigned int hsub;
  154. unsigned int vsub;
  155. int ret;
  156. int i;
  157. hsub = drm_format_horz_chroma_subsampling(mode_cmd->pixel_format);
  158. vsub = drm_format_vert_chroma_subsampling(mode_cmd->pixel_format);
  159. for (i = 0; i < drm_format_num_planes(mode_cmd->pixel_format); i++) {
  160. unsigned int width = mode_cmd->width / (i ? hsub : 1);
  161. unsigned int height = mode_cmd->height / (i ? vsub : 1);
  162. unsigned int min_size;
  163. obj = drm_gem_object_lookup(dev, file_priv, mode_cmd->handles[i]);
  164. if (!obj) {
  165. dev_err(dev->dev, "Failed to lookup GEM object\n");
  166. ret = -ENXIO;
  167. goto err_gem_object_unreference;
  168. }
  169. min_size = (height - 1) * mode_cmd->pitches[i]
  170. + width * drm_format_plane_cpp(mode_cmd->pixel_format, i)
  171. + mode_cmd->offsets[i];
  172. if (obj->size < min_size) {
  173. drm_gem_object_unreference_unlocked(obj);
  174. ret = -EINVAL;
  175. goto err_gem_object_unreference;
  176. }
  177. objs[i] = to_drm_gem_cma_obj(obj);
  178. }
  179. fb_cma = drm_fb_cma_alloc(dev, mode_cmd, objs, i, &drm_fb_cma_funcs);
  180. if (IS_ERR(fb_cma)) {
  181. ret = PTR_ERR(fb_cma);
  182. goto err_gem_object_unreference;
  183. }
  184. return &fb_cma->fb;
  185. err_gem_object_unreference:
  186. for (i--; i >= 0; i--)
  187. drm_gem_object_unreference_unlocked(&objs[i]->base);
  188. return ERR_PTR(ret);
  189. }
  190. EXPORT_SYMBOL_GPL(drm_fb_cma_create);
  191. /**
  192. * drm_fb_cma_get_gem_obj() - Get CMA GEM object for framebuffer
  193. * @fb: The framebuffer
  194. * @plane: Which plane
  195. *
  196. * Return the CMA GEM object for given framebuffer.
  197. *
  198. * This function will usually be called from the CRTC callback functions.
  199. */
  200. struct drm_gem_cma_object *drm_fb_cma_get_gem_obj(struct drm_framebuffer *fb,
  201. unsigned int plane)
  202. {
  203. struct drm_fb_cma *fb_cma = to_fb_cma(fb);
  204. if (plane >= 4)
  205. return NULL;
  206. return fb_cma->obj[plane];
  207. }
  208. EXPORT_SYMBOL_GPL(drm_fb_cma_get_gem_obj);
  209. #ifdef CONFIG_DEBUG_FS
  210. /*
  211. * drm_fb_cma_describe() - Helper to dump information about a single
  212. * CMA framebuffer object
  213. */
  214. static void drm_fb_cma_describe(struct drm_framebuffer *fb, struct seq_file *m)
  215. {
  216. struct drm_fb_cma *fb_cma = to_fb_cma(fb);
  217. int i, n = drm_format_num_planes(fb->pixel_format);
  218. seq_printf(m, "fb: %dx%d@%4.4s\n", fb->width, fb->height,
  219. (char *)&fb->pixel_format);
  220. for (i = 0; i < n; i++) {
  221. seq_printf(m, " %d: offset=%d pitch=%d, obj: ",
  222. i, fb->offsets[i], fb->pitches[i]);
  223. drm_gem_cma_describe(fb_cma->obj[i], m);
  224. }
  225. }
  226. /**
  227. * drm_fb_cma_debugfs_show() - Helper to list CMA framebuffer objects
  228. * in debugfs.
  229. */
  230. int drm_fb_cma_debugfs_show(struct seq_file *m, void *arg)
  231. {
  232. struct drm_info_node *node = (struct drm_info_node *) m->private;
  233. struct drm_device *dev = node->minor->dev;
  234. struct drm_framebuffer *fb;
  235. mutex_lock(&dev->mode_config.fb_lock);
  236. drm_for_each_fb(fb, dev)
  237. drm_fb_cma_describe(fb, m);
  238. mutex_unlock(&dev->mode_config.fb_lock);
  239. return 0;
  240. }
  241. EXPORT_SYMBOL_GPL(drm_fb_cma_debugfs_show);
  242. #endif
  243. static struct fb_ops drm_fbdev_cma_ops = {
  244. .owner = THIS_MODULE,
  245. .fb_fillrect = drm_fb_helper_sys_fillrect,
  246. .fb_copyarea = drm_fb_helper_sys_copyarea,
  247. .fb_imageblit = drm_fb_helper_sys_imageblit,
  248. .fb_check_var = drm_fb_helper_check_var,
  249. .fb_set_par = drm_fb_helper_set_par,
  250. .fb_blank = drm_fb_helper_blank,
  251. .fb_pan_display = drm_fb_helper_pan_display,
  252. .fb_setcmap = drm_fb_helper_setcmap,
  253. };
  254. static int drm_fbdev_cma_deferred_io_mmap(struct fb_info *info,
  255. struct vm_area_struct *vma)
  256. {
  257. fb_deferred_io_mmap(info, vma);
  258. vma->vm_page_prot = pgprot_writecombine(vma->vm_page_prot);
  259. return 0;
  260. }
  261. static int drm_fbdev_cma_defio_init(struct fb_info *fbi,
  262. struct drm_gem_cma_object *cma_obj)
  263. {
  264. struct fb_deferred_io *fbdefio;
  265. struct fb_ops *fbops;
  266. /*
  267. * Per device structures are needed because:
  268. * fbops: fb_deferred_io_cleanup() clears fbops.fb_mmap
  269. * fbdefio: individual delays
  270. */
  271. fbdefio = kzalloc(sizeof(*fbdefio), GFP_KERNEL);
  272. fbops = kzalloc(sizeof(*fbops), GFP_KERNEL);
  273. if (!fbdefio || !fbops) {
  274. kfree(fbdefio);
  275. return -ENOMEM;
  276. }
  277. /* can't be offset from vaddr since dirty() uses cma_obj */
  278. fbi->screen_buffer = cma_obj->vaddr;
  279. /* fb_deferred_io_fault() needs a physical address */
  280. fbi->fix.smem_start = page_to_phys(virt_to_page(fbi->screen_buffer));
  281. *fbops = *fbi->fbops;
  282. fbi->fbops = fbops;
  283. fbdefio->delay = msecs_to_jiffies(DEFAULT_FBDEFIO_DELAY_MS);
  284. fbdefio->deferred_io = drm_fb_helper_deferred_io;
  285. fbi->fbdefio = fbdefio;
  286. fb_deferred_io_init(fbi);
  287. fbi->fbops->fb_mmap = drm_fbdev_cma_deferred_io_mmap;
  288. return 0;
  289. }
  290. static void drm_fbdev_cma_defio_fini(struct fb_info *fbi)
  291. {
  292. if (!fbi->fbdefio)
  293. return;
  294. fb_deferred_io_cleanup(fbi);
  295. kfree(fbi->fbdefio);
  296. kfree(fbi->fbops);
  297. }
  298. /*
  299. * For use in a (struct drm_fb_helper_funcs *)->fb_probe callback function that
  300. * needs custom struct drm_framebuffer_funcs, like dirty() for deferred_io use.
  301. */
  302. int drm_fbdev_cma_create_with_funcs(struct drm_fb_helper *helper,
  303. struct drm_fb_helper_surface_size *sizes,
  304. struct drm_framebuffer_funcs *funcs)
  305. {
  306. struct drm_fbdev_cma *fbdev_cma = to_fbdev_cma(helper);
  307. struct drm_mode_fb_cmd2 mode_cmd = { 0 };
  308. struct drm_device *dev = helper->dev;
  309. struct drm_gem_cma_object *obj;
  310. struct drm_framebuffer *fb;
  311. unsigned int bytes_per_pixel;
  312. unsigned long offset;
  313. struct fb_info *fbi;
  314. size_t size;
  315. int ret;
  316. DRM_DEBUG_KMS("surface width(%d), height(%d) and bpp(%d)\n",
  317. sizes->surface_width, sizes->surface_height,
  318. sizes->surface_bpp);
  319. bytes_per_pixel = DIV_ROUND_UP(sizes->surface_bpp, 8);
  320. mode_cmd.width = sizes->surface_width;
  321. mode_cmd.height = sizes->surface_height;
  322. mode_cmd.pitches[0] = sizes->surface_width * bytes_per_pixel;
  323. mode_cmd.pixel_format = drm_mode_legacy_fb_format(sizes->surface_bpp,
  324. sizes->surface_depth);
  325. size = mode_cmd.pitches[0] * mode_cmd.height;
  326. obj = drm_gem_cma_create(dev, size);
  327. if (IS_ERR(obj))
  328. return -ENOMEM;
  329. fbi = drm_fb_helper_alloc_fbi(helper);
  330. if (IS_ERR(fbi)) {
  331. ret = PTR_ERR(fbi);
  332. goto err_gem_free_object;
  333. }
  334. fbdev_cma->fb = drm_fb_cma_alloc(dev, &mode_cmd, &obj, 1, funcs);
  335. if (IS_ERR(fbdev_cma->fb)) {
  336. dev_err(dev->dev, "Failed to allocate DRM framebuffer.\n");
  337. ret = PTR_ERR(fbdev_cma->fb);
  338. goto err_fb_info_destroy;
  339. }
  340. fb = &fbdev_cma->fb->fb;
  341. helper->fb = fb;
  342. fbi->par = helper;
  343. fbi->flags = FBINFO_FLAG_DEFAULT;
  344. fbi->fbops = &drm_fbdev_cma_ops;
  345. drm_fb_helper_fill_fix(fbi, fb->pitches[0], fb->depth);
  346. drm_fb_helper_fill_var(fbi, helper, sizes->fb_width, sizes->fb_height);
  347. offset = fbi->var.xoffset * bytes_per_pixel;
  348. offset += fbi->var.yoffset * fb->pitches[0];
  349. dev->mode_config.fb_base = (resource_size_t)obj->paddr;
  350. fbi->screen_base = obj->vaddr + offset;
  351. fbi->fix.smem_start = (unsigned long)(obj->paddr + offset);
  352. fbi->screen_size = size;
  353. fbi->fix.smem_len = size;
  354. if (funcs->dirty) {
  355. ret = drm_fbdev_cma_defio_init(fbi, obj);
  356. if (ret)
  357. goto err_cma_destroy;
  358. }
  359. return 0;
  360. err_cma_destroy:
  361. drm_framebuffer_unregister_private(&fbdev_cma->fb->fb);
  362. drm_fb_cma_destroy(&fbdev_cma->fb->fb);
  363. err_fb_info_destroy:
  364. drm_fb_helper_release_fbi(helper);
  365. err_gem_free_object:
  366. dev->driver->gem_free_object(&obj->base);
  367. return ret;
  368. }
  369. EXPORT_SYMBOL(drm_fbdev_cma_create_with_funcs);
  370. static int drm_fbdev_cma_create(struct drm_fb_helper *helper,
  371. struct drm_fb_helper_surface_size *sizes)
  372. {
  373. return drm_fbdev_cma_create_with_funcs(helper, sizes, &drm_fb_cma_funcs);
  374. }
  375. static const struct drm_fb_helper_funcs drm_fb_cma_helper_funcs = {
  376. .fb_probe = drm_fbdev_cma_create,
  377. };
  378. /**
  379. * drm_fbdev_cma_init_with_funcs() - Allocate and initializes a drm_fbdev_cma struct
  380. * @dev: DRM device
  381. * @preferred_bpp: Preferred bits per pixel for the device
  382. * @num_crtc: Number of CRTCs
  383. * @max_conn_count: Maximum number of connectors
  384. * @funcs: fb helper functions, in particular fb_probe()
  385. *
  386. * Returns a newly allocated drm_fbdev_cma struct or a ERR_PTR.
  387. */
  388. struct drm_fbdev_cma *drm_fbdev_cma_init_with_funcs(struct drm_device *dev,
  389. unsigned int preferred_bpp, unsigned int num_crtc,
  390. unsigned int max_conn_count, const struct drm_fb_helper_funcs *funcs)
  391. {
  392. struct drm_fbdev_cma *fbdev_cma;
  393. struct drm_fb_helper *helper;
  394. int ret;
  395. fbdev_cma = kzalloc(sizeof(*fbdev_cma), GFP_KERNEL);
  396. if (!fbdev_cma) {
  397. dev_err(dev->dev, "Failed to allocate drm fbdev.\n");
  398. return ERR_PTR(-ENOMEM);
  399. }
  400. helper = &fbdev_cma->fb_helper;
  401. drm_fb_helper_prepare(dev, helper, funcs);
  402. ret = drm_fb_helper_init(dev, helper, num_crtc, max_conn_count);
  403. if (ret < 0) {
  404. dev_err(dev->dev, "Failed to initialize drm fb helper.\n");
  405. goto err_free;
  406. }
  407. ret = drm_fb_helper_single_add_all_connectors(helper);
  408. if (ret < 0) {
  409. dev_err(dev->dev, "Failed to add connectors.\n");
  410. goto err_drm_fb_helper_fini;
  411. }
  412. ret = drm_fb_helper_initial_config(helper, preferred_bpp);
  413. if (ret < 0) {
  414. dev_err(dev->dev, "Failed to set initial hw configuration.\n");
  415. goto err_drm_fb_helper_fini;
  416. }
  417. return fbdev_cma;
  418. err_drm_fb_helper_fini:
  419. drm_fb_helper_fini(helper);
  420. err_free:
  421. kfree(fbdev_cma);
  422. return ERR_PTR(ret);
  423. }
  424. EXPORT_SYMBOL_GPL(drm_fbdev_cma_init_with_funcs);
  425. /**
  426. * drm_fbdev_cma_init() - Allocate and initializes a drm_fbdev_cma struct
  427. * @dev: DRM device
  428. * @preferred_bpp: Preferred bits per pixel for the device
  429. * @num_crtc: Number of CRTCs
  430. * @max_conn_count: Maximum number of connectors
  431. *
  432. * Returns a newly allocated drm_fbdev_cma struct or a ERR_PTR.
  433. */
  434. struct drm_fbdev_cma *drm_fbdev_cma_init(struct drm_device *dev,
  435. unsigned int preferred_bpp, unsigned int num_crtc,
  436. unsigned int max_conn_count)
  437. {
  438. return drm_fbdev_cma_init_with_funcs(dev, preferred_bpp, num_crtc,
  439. max_conn_count, &drm_fb_cma_helper_funcs);
  440. }
  441. EXPORT_SYMBOL_GPL(drm_fbdev_cma_init);
  442. /**
  443. * drm_fbdev_cma_fini() - Free drm_fbdev_cma struct
  444. * @fbdev_cma: The drm_fbdev_cma struct
  445. */
  446. void drm_fbdev_cma_fini(struct drm_fbdev_cma *fbdev_cma)
  447. {
  448. drm_fb_helper_unregister_fbi(&fbdev_cma->fb_helper);
  449. drm_fbdev_cma_defio_fini(fbdev_cma->fb_helper.fbdev);
  450. drm_fb_helper_release_fbi(&fbdev_cma->fb_helper);
  451. if (fbdev_cma->fb) {
  452. drm_framebuffer_unregister_private(&fbdev_cma->fb->fb);
  453. drm_fb_cma_destroy(&fbdev_cma->fb->fb);
  454. }
  455. drm_fb_helper_fini(&fbdev_cma->fb_helper);
  456. kfree(fbdev_cma);
  457. }
  458. EXPORT_SYMBOL_GPL(drm_fbdev_cma_fini);
  459. /**
  460. * drm_fbdev_cma_restore_mode() - Restores initial framebuffer mode
  461. * @fbdev_cma: The drm_fbdev_cma struct, may be NULL
  462. *
  463. * This function is usually called from the DRM drivers lastclose callback.
  464. */
  465. void drm_fbdev_cma_restore_mode(struct drm_fbdev_cma *fbdev_cma)
  466. {
  467. if (fbdev_cma)
  468. drm_fb_helper_restore_fbdev_mode_unlocked(&fbdev_cma->fb_helper);
  469. }
  470. EXPORT_SYMBOL_GPL(drm_fbdev_cma_restore_mode);
  471. /**
  472. * drm_fbdev_cma_hotplug_event() - Poll for hotpulug events
  473. * @fbdev_cma: The drm_fbdev_cma struct, may be NULL
  474. *
  475. * This function is usually called from the DRM drivers output_poll_changed
  476. * callback.
  477. */
  478. void drm_fbdev_cma_hotplug_event(struct drm_fbdev_cma *fbdev_cma)
  479. {
  480. if (fbdev_cma)
  481. drm_fb_helper_hotplug_event(&fbdev_cma->fb_helper);
  482. }
  483. EXPORT_SYMBOL_GPL(drm_fbdev_cma_hotplug_event);