1 /*
2  * Copyright (c) 2006-2009 Red Hat Inc.
3  * Copyright (c) 2006-2008 Intel Corporation
4  * Copyright (c) 2007 Dave Airlie <airlied@linux.ie>
5  *
6  * DRM framebuffer helper functions
7  *
8  * Permission to use, copy, modify, distribute, and sell this software and its
9  * documentation for any purpose is hereby granted without fee, provided that
10  * the above copyright notice appear in all copies and that both that copyright
11  * notice and this permission notice appear in supporting documentation, and
12  * that the name of the copyright holders not be used in advertising or
13  * publicity pertaining to distribution of the software without specific,
14  * written prior permission.  The copyright holders make no representations
15  * about the suitability of this software for any purpose.  It is provided "as
16  * is" without express or implied warranty.
17  *
18  * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
19  * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
20  * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
21  * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
22  * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
23  * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
24  * OF THIS SOFTWARE.
25  *
26  * Authors:
27  *      Dave Airlie <airlied@linux.ie>
28  *      Jesse Barnes <jesse.barnes@intel.com>
29  */
30 #ifndef DRM_FB_HELPER_H
31 #define DRM_FB_HELPER_H
32 
33 struct drm_fb_helper;
34 
35 
36 enum mode_set_atomic {
37 	LEAVE_ATOMIC_MODE_SET,
38 	ENTER_ATOMIC_MODE_SET,
39 };
40 
41 struct drm_fb_offset {
42 	int x, y;
43 };
44 
45 struct drm_fb_helper_crtc {
46 	struct drm_mode_set mode_set;
47 	struct drm_display_mode *desired_mode;
48 	int x, y;
49 };
50 
51 /**
52  * struct drm_fb_helper_surface_size - describes fbdev size and scanout surface size
53  * @fb_width: fbdev width
54  * @fb_height: fbdev height
55  * @surface_width: scanout buffer width
56  * @surface_height: scanout buffer height
57  * @surface_bpp: scanout buffer bpp
58  * @surface_depth: scanout buffer depth
59  *
60  * Note that the scanout surface width/height may be larger than the fbdev
61  * width/height.  In case of multiple displays, the scanout surface is sized
62  * according to the largest width/height (so it is large enough for all CRTCs
63  * to scanout).  But the fbdev width/height is sized to the minimum width/
64  * height of all the displays.  This ensures that fbcon fits on the smallest
65  * of the attached displays.
66  *
67  * So what is passed to drm_fb_helper_fill_var() should be fb_width/fb_height,
68  * rather than the surface size.
69  */
70 struct drm_fb_helper_surface_size {
71 	u32 fb_width;
72 	u32 fb_height;
73 	u32 surface_width;
74 	u32 surface_height;
75 	u32 surface_bpp;
76 	u32 surface_depth;
77 };
78 
79 /**
80  * struct drm_fb_helper_funcs - driver callbacks for the fbdev emulation library
81  *
82  * Driver callbacks used by the fbdev emulation helper library.
83  */
84 struct drm_fb_helper_funcs {
85 	/**
86 	 * @gamma_set:
87 	 *
88 	 * Set the given gamma LUT register on the given CRTC.
89 	 *
90 	 * This callback is optional.
91 	 *
92 	 * FIXME:
93 	 *
94 	 * This callback is functionally redundant with the core gamma table
95 	 * support and simply exists because the fbdev hasn't yet been
96 	 * refactored to use the core gamma table interfaces.
97 	 */
98 	void (*gamma_set)(struct drm_crtc *crtc, u16 red, u16 green,
99 			  u16 blue, int regno);
100 	/**
101 	 * @gamma_get:
102 	 *
103 	 * Read the given gamma LUT register on the given CRTC, used to save the
104 	 * current LUT when force-restoring the fbdev for e.g. kdbg.
105 	 *
106 	 * This callback is optional.
107 	 *
108 	 * FIXME:
109 	 *
110 	 * This callback is functionally redundant with the core gamma table
111 	 * support and simply exists because the fbdev hasn't yet been
112 	 * refactored to use the core gamma table interfaces.
113 	 */
114 	void (*gamma_get)(struct drm_crtc *crtc, u16 *red, u16 *green,
115 			  u16 *blue, int regno);
116 
117 	/**
118 	 * @fb_probe:
119 	 *
120 	 * Driver callback to allocate and initialize the fbdev info structure.
121 	 * Furthermore it also needs to allocate the DRM framebuffer used to
122 	 * back the fbdev.
123 	 *
124 	 * This callback is mandatory.
125 	 *
126 	 * RETURNS:
127 	 *
128 	 * The driver should return 0 on success and a negative error code on
129 	 * failure.
130 	 */
131 	int (*fb_probe)(struct drm_fb_helper *helper,
132 			struct drm_fb_helper_surface_size *sizes);
133 
134 	/**
135 	 * @initial_config:
136 	 *
137 	 * Driver callback to setup an initial fbdev display configuration.
138 	 * Drivers can use this callback to tell the fbdev emulation what the
139 	 * preferred initial configuration is. This is useful to implement
140 	 * smooth booting where the fbdev (and subsequently all userspace) never
141 	 * changes the mode, but always inherits the existing configuration.
142 	 *
143 	 * This callback is optional.
144 	 *
145 	 * RETURNS:
146 	 *
147 	 * The driver should return true if a suitable initial configuration has
148 	 * been filled out and false when the fbdev helper should fall back to
149 	 * the default probing logic.
150 	 */
151 	bool (*initial_config)(struct drm_fb_helper *fb_helper,
152 			       struct drm_fb_helper_crtc **crtcs,
153 			       struct drm_display_mode **modes,
154 			       struct drm_fb_offset *offsets,
155 			       bool *enabled, int width, int height);
156 };
157 
158 struct drm_fb_helper_connector {
159 	struct drm_connector *connector;
160 };
161 
162 /**
163  * struct drm_fb_helper - main structure to emulate fbdev on top of KMS
164  * @fb: Scanout framebuffer object
165  * @dev: DRM device
166  * @crtc_count: number of possible CRTCs
167  * @crtc_info: per-CRTC helper state (mode, x/y offset, etc)
168  * @connector_count: number of connected connectors
169  * @connector_info_alloc_count: size of connector_info
170  * @connector_info: array of per-connector information
171  * @funcs: driver callbacks for fb helper
172  * @fbdev: emulated fbdev device info struct
173  * @pseudo_palette: fake palette of 16 colors
174  * @dirty_clip: clip rectangle used with deferred_io to accumulate damage to
175  *              the screen buffer
176  * @dirty_lock: spinlock protecting @dirty_clip
177  * @dirty_work: worker used to flush the framebuffer
178  *
179  * This is the main structure used by the fbdev helpers. Drivers supporting
180  * fbdev emulation should embedded this into their overall driver structure.
181  * Drivers must also fill out a struct &drm_fb_helper_funcs with a few
182  * operations.
183  */
184 struct drm_fb_helper {
185 	struct drm_framebuffer *fb;
186 	struct drm_device *dev;
187 	int crtc_count;
188 	struct drm_fb_helper_crtc *crtc_info;
189 	int connector_count;
190 	int connector_info_alloc_count;
191 	struct drm_fb_helper_connector **connector_info;
192 	const struct drm_fb_helper_funcs *funcs;
193 	struct fb_info *fbdev;
194 	u32 pseudo_palette[17];
195 	struct drm_clip_rect dirty_clip;
196 	struct lock dirty_lock;
197 	struct work_struct dirty_work;
198 
199 	/**
200 	 * @kernel_fb_list:
201 	 *
202 	 * Entry on the global kernel_fb_helper_list, used for kgdb entry/exit.
203 	 */
204 	struct list_head kernel_fb_list;
205 
206 	/**
207 	 * @delayed_hotplug:
208 	 *
209 	 * A hotplug was received while fbdev wasn't in control of the DRM
210 	 * device, i.e. another KMS master was active. The output configuration
211 	 * needs to be reprobe when fbdev is in control again.
212 	 */
213 	bool delayed_hotplug;
214 
215 	/**
216 	 * @atomic:
217 	 *
218 	 * Use atomic updates for restore_fbdev_mode(), etc.  This defaults to
219 	 * true if driver has DRIVER_ATOMIC feature flag, but drivers can
220 	 * override it to true after drm_fb_helper_init() if they support atomic
221 	 * modeset but do not yet advertise DRIVER_ATOMIC (note that fb-helper
222 	 * does not require ASYNC commits).
223 	 */
224 	bool atomic;
225 };
226 
227 #ifdef CONFIG_DRM_FBDEV_EMULATION
228 int drm_fb_helper_modinit(void);
229 void drm_fb_helper_prepare(struct drm_device *dev, struct drm_fb_helper *helper,
230 			   const struct drm_fb_helper_funcs *funcs);
231 int drm_fb_helper_init(struct drm_device *dev,
232 		       struct drm_fb_helper *helper, int crtc_count,
233 		       int max_conn);
234 void drm_fb_helper_fini(struct drm_fb_helper *helper);
235 int drm_fb_helper_blank(int blank, struct fb_info *info);
236 int drm_fb_helper_pan_display(struct fb_var_screeninfo *var,
237 			      struct fb_info *info);
238 int drm_fb_helper_set_par(struct fb_info *info);
239 int drm_fb_helper_check_var(struct fb_var_screeninfo *var,
240 			    struct fb_info *info);
241 
242 int drm_fb_helper_restore_fbdev_mode_unlocked(struct drm_fb_helper *fb_helper);
243 
244 struct fb_info *drm_fb_helper_alloc_fbi(struct drm_fb_helper *fb_helper);
245 void drm_fb_helper_unregister_fbi(struct drm_fb_helper *fb_helper);
246 void drm_fb_helper_release_fbi(struct drm_fb_helper *fb_helper);
247 void drm_fb_helper_fill_var(struct fb_info *info, struct drm_fb_helper *fb_helper,
248 			    uint32_t fb_width, uint32_t fb_height);
249 void drm_fb_helper_fill_fix(struct fb_info *info, uint32_t pitch,
250 			    uint32_t depth);
251 
252 void drm_fb_helper_unlink_fbi(struct drm_fb_helper *fb_helper);
253 
254 void drm_fb_helper_deferred_io(struct fb_info *info,
255 			       struct list_head *pagelist);
256 
257 ssize_t drm_fb_helper_sys_read(struct fb_info *info, char __user *buf,
258 			       size_t count, loff_t *ppos);
259 ssize_t drm_fb_helper_sys_write(struct fb_info *info, const char __user *buf,
260 				size_t count, loff_t *ppos);
261 
262 void drm_fb_helper_sys_fillrect(struct fb_info *info,
263 				const struct fb_fillrect *rect);
264 void drm_fb_helper_sys_copyarea(struct fb_info *info,
265 				const struct fb_copyarea *area);
266 void drm_fb_helper_sys_imageblit(struct fb_info *info,
267 				 const struct fb_image *image);
268 
269 void drm_fb_helper_cfb_fillrect(struct fb_info *info,
270 				const struct fb_fillrect *rect);
271 void drm_fb_helper_cfb_copyarea(struct fb_info *info,
272 				const struct fb_copyarea *area);
273 void drm_fb_helper_cfb_imageblit(struct fb_info *info,
274 				 const struct fb_image *image);
275 
276 void drm_fb_helper_set_suspend(struct drm_fb_helper *fb_helper, int state);
277 
278 int drm_fb_helper_setcmap(struct fb_cmap *cmap, struct fb_info *info);
279 
280 int drm_fb_helper_hotplug_event(struct drm_fb_helper *fb_helper);
281 int drm_fb_helper_initial_config(struct drm_fb_helper *fb_helper, int bpp_sel);
282 int drm_fb_helper_single_add_all_connectors(struct drm_fb_helper *fb_helper);
283 int drm_fb_helper_debug_enter(struct fb_info *info);
284 int drm_fb_helper_debug_leave(struct fb_info *info);
285 struct drm_display_mode *
286 drm_has_preferred_mode(struct drm_fb_helper_connector *fb_connector,
287 			int width, int height);
288 struct drm_display_mode *
289 drm_pick_cmdline_mode(struct drm_fb_helper_connector *fb_helper_conn,
290 		      int width, int height);
291 
292 int drm_fb_helper_add_one_connector(struct drm_fb_helper *fb_helper, struct drm_connector *connector);
293 int drm_fb_helper_remove_one_connector(struct drm_fb_helper *fb_helper,
294 				       struct drm_connector *connector);
295 #else
296 static inline int drm_fb_helper_modinit(void)
297 {
298 	return 0;
299 }
300 
301 static inline void drm_fb_helper_prepare(struct drm_device *dev,
302 					struct drm_fb_helper *helper,
303 					const struct drm_fb_helper_funcs *funcs)
304 {
305 }
306 
307 static inline int drm_fb_helper_init(struct drm_device *dev,
308 		       struct drm_fb_helper *helper, int crtc_count,
309 		       int max_conn)
310 {
311 	return 0;
312 }
313 
314 static inline void drm_fb_helper_fini(struct drm_fb_helper *helper)
315 {
316 }
317 
318 static inline int drm_fb_helper_blank(int blank, struct fb_info *info)
319 {
320 	return 0;
321 }
322 
323 static inline int drm_fb_helper_pan_display(struct fb_var_screeninfo *var,
324 					    struct fb_info *info)
325 {
326 	return 0;
327 }
328 
329 static inline int drm_fb_helper_set_par(struct fb_info *info)
330 {
331 	return 0;
332 }
333 
334 static inline int drm_fb_helper_check_var(struct fb_var_screeninfo *var,
335 					  struct fb_info *info)
336 {
337 	return 0;
338 }
339 
340 static inline int
341 drm_fb_helper_restore_fbdev_mode_unlocked(struct drm_fb_helper *fb_helper)
342 {
343 	return 0;
344 }
345 
346 static inline struct fb_info *
347 drm_fb_helper_alloc_fbi(struct drm_fb_helper *fb_helper)
348 {
349 	return NULL;
350 }
351 
352 static inline void drm_fb_helper_unregister_fbi(struct drm_fb_helper *fb_helper)
353 {
354 }
355 static inline void drm_fb_helper_release_fbi(struct drm_fb_helper *fb_helper)
356 {
357 }
358 
359 static inline void drm_fb_helper_fill_var(struct fb_info *info,
360 					  struct drm_fb_helper *fb_helper,
361 					  uint32_t fb_width, uint32_t fb_height)
362 {
363 }
364 
365 static inline void drm_fb_helper_fill_fix(struct fb_info *info, uint32_t pitch,
366 					  uint32_t depth)
367 {
368 }
369 
370 static inline int drm_fb_helper_setcmap(struct fb_cmap *cmap,
371 					struct fb_info *info)
372 {
373 	return 0;
374 }
375 
376 static inline void drm_fb_helper_unlink_fbi(struct drm_fb_helper *fb_helper)
377 {
378 }
379 
380 static inline void drm_fb_helper_deferred_io(struct fb_info *info,
381 					     struct list_head *pagelist)
382 {
383 }
384 
385 static inline ssize_t drm_fb_helper_sys_read(struct fb_info *info,
386 					     char __user *buf, size_t count,
387 					     loff_t *ppos)
388 {
389 	return -ENODEV;
390 }
391 
392 static inline ssize_t drm_fb_helper_sys_write(struct fb_info *info,
393 					      const char __user *buf,
394 					      size_t count, loff_t *ppos)
395 {
396 	return -ENODEV;
397 }
398 
399 static inline void drm_fb_helper_sys_fillrect(struct fb_info *info,
400 					      const struct fb_fillrect *rect)
401 {
402 }
403 
404 static inline void drm_fb_helper_sys_copyarea(struct fb_info *info,
405 					      const struct fb_copyarea *area)
406 {
407 }
408 
409 static inline void drm_fb_helper_sys_imageblit(struct fb_info *info,
410 					       const struct fb_image *image)
411 {
412 }
413 
414 static inline void drm_fb_helper_cfb_fillrect(struct fb_info *info,
415 					      const struct fb_fillrect *rect)
416 {
417 }
418 
419 static inline void drm_fb_helper_cfb_copyarea(struct fb_info *info,
420 					      const struct fb_copyarea *area)
421 {
422 }
423 
424 static inline void drm_fb_helper_cfb_imageblit(struct fb_info *info,
425 					       const struct fb_image *image)
426 {
427 }
428 
429 static inline void drm_fb_helper_set_suspend(struct drm_fb_helper *fb_helper,
430 					     int state)
431 {
432 }
433 
434 static inline int drm_fb_helper_hotplug_event(struct drm_fb_helper *fb_helper)
435 {
436 	return 0;
437 }
438 
439 static inline int drm_fb_helper_initial_config(struct drm_fb_helper *fb_helper,
440 					       int bpp_sel)
441 {
442 	return 0;
443 }
444 
445 static inline int
446 drm_fb_helper_single_add_all_connectors(struct drm_fb_helper *fb_helper)
447 {
448 	return 0;
449 }
450 
451 static inline int drm_fb_helper_debug_enter(struct fb_info *info)
452 {
453 	return 0;
454 }
455 
456 static inline int drm_fb_helper_debug_leave(struct fb_info *info)
457 {
458 	return 0;
459 }
460 
461 static inline struct drm_display_mode *
462 drm_has_preferred_mode(struct drm_fb_helper_connector *fb_connector,
463 		       int width, int height)
464 {
465 	return NULL;
466 }
467 
468 static inline struct drm_display_mode *
469 drm_pick_cmdline_mode(struct drm_fb_helper_connector *fb_helper_conn,
470 		      int width, int height)
471 {
472 	return NULL;
473 }
474 
475 static inline int
476 drm_fb_helper_add_one_connector(struct drm_fb_helper *fb_helper,
477 				struct drm_connector *connector)
478 {
479 	return 0;
480 }
481 
482 static inline int
483 drm_fb_helper_remove_one_connector(struct drm_fb_helper *fb_helper,
484 				   struct drm_connector *connector)
485 {
486 	return 0;
487 }
488 #endif
489 #endif
490