xref: /linux/drivers/gpu/drm/drm_modes.c (revision b8bb76713ec50df2f11efee386e16f93d51e1076)
1 /*
2  * The list_sort function is (presumably) licensed under the GPL (see the
3  * top level "COPYING" file for details).
4  *
5  * The remainder of this file is:
6  *
7  * Copyright © 1997-2003 by The XFree86 Project, Inc.
8  * Copyright © 2007 Dave Airlie
9  * Copyright © 2007-2008 Intel Corporation
10  *   Jesse Barnes <jesse.barnes@intel.com>
11  *
12  * Permission is hereby granted, free of charge, to any person obtaining a
13  * copy of this software and associated documentation files (the "Software"),
14  * to deal in the Software without restriction, including without limitation
15  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
16  * and/or sell copies of the Software, and to permit persons to whom the
17  * Software is furnished to do so, subject to the following conditions:
18  *
19  * The above copyright notice and this permission notice shall be included in
20  * all copies or substantial portions of the Software.
21  *
22  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
23  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
24  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
25  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
26  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
27  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
28  * OTHER DEALINGS IN THE SOFTWARE.
29  *
30  * Except as contained in this notice, the name of the copyright holder(s)
31  * and author(s) shall not be used in advertising or otherwise to promote
32  * the sale, use or other dealings in this Software without prior written
33  * authorization from the copyright holder(s) and author(s).
34  */
35 
36 #include <linux/list.h>
37 #include "drmP.h"
38 #include "drm.h"
39 #include "drm_crtc.h"
40 
41 /**
42  * drm_mode_debug_printmodeline - debug print a mode
43  * @dev: DRM device
44  * @mode: mode to print
45  *
46  * LOCKING:
47  * None.
48  *
49  * Describe @mode using DRM_DEBUG.
50  */
51 void drm_mode_debug_printmodeline(struct drm_display_mode *mode)
52 {
53 	DRM_DEBUG("Modeline %d:\"%s\" %d %d %d %d %d %d %d %d %d %d 0x%x 0x%x\n",
54 		  mode->base.id, mode->name, mode->vrefresh, mode->clock,
55 		  mode->hdisplay, mode->hsync_start,
56 		  mode->hsync_end, mode->htotal,
57 		  mode->vdisplay, mode->vsync_start,
58 		  mode->vsync_end, mode->vtotal, mode->type, mode->flags);
59 }
60 EXPORT_SYMBOL(drm_mode_debug_printmodeline);
61 
62 /**
63  * drm_mode_set_name - set the name on a mode
64  * @mode: name will be set in this mode
65  *
66  * LOCKING:
67  * None.
68  *
69  * Set the name of @mode to a standard format.
70  */
71 void drm_mode_set_name(struct drm_display_mode *mode)
72 {
73 	snprintf(mode->name, DRM_DISPLAY_MODE_LEN, "%dx%d", mode->hdisplay,
74 		 mode->vdisplay);
75 }
76 EXPORT_SYMBOL(drm_mode_set_name);
77 
78 /**
79  * drm_mode_list_concat - move modes from one list to another
80  * @head: source list
81  * @new: dst list
82  *
83  * LOCKING:
84  * Caller must ensure both lists are locked.
85  *
86  * Move all the modes from @head to @new.
87  */
88 void drm_mode_list_concat(struct list_head *head, struct list_head *new)
89 {
90 
91 	struct list_head *entry, *tmp;
92 
93 	list_for_each_safe(entry, tmp, head) {
94 		list_move_tail(entry, new);
95 	}
96 }
97 EXPORT_SYMBOL(drm_mode_list_concat);
98 
99 /**
100  * drm_mode_width - get the width of a mode
101  * @mode: mode
102  *
103  * LOCKING:
104  * None.
105  *
106  * Return @mode's width (hdisplay) value.
107  *
108  * FIXME: is this needed?
109  *
110  * RETURNS:
111  * @mode->hdisplay
112  */
113 int drm_mode_width(struct drm_display_mode *mode)
114 {
115 	return mode->hdisplay;
116 
117 }
118 EXPORT_SYMBOL(drm_mode_width);
119 
120 /**
121  * drm_mode_height - get the height of a mode
122  * @mode: mode
123  *
124  * LOCKING:
125  * None.
126  *
127  * Return @mode's height (vdisplay) value.
128  *
129  * FIXME: is this needed?
130  *
131  * RETURNS:
132  * @mode->vdisplay
133  */
134 int drm_mode_height(struct drm_display_mode *mode)
135 {
136 	return mode->vdisplay;
137 }
138 EXPORT_SYMBOL(drm_mode_height);
139 
140 /**
141  * drm_mode_vrefresh - get the vrefresh of a mode
142  * @mode: mode
143  *
144  * LOCKING:
145  * None.
146  *
147  * Return @mode's vrefresh rate or calculate it if necessary.
148  *
149  * FIXME: why is this needed?  shouldn't vrefresh be set already?
150  *
151  * RETURNS:
152  * Vertical refresh rate of @mode x 1000. For precision reasons.
153  */
154 int drm_mode_vrefresh(struct drm_display_mode *mode)
155 {
156 	int refresh = 0;
157 	unsigned int calc_val;
158 
159 	if (mode->vrefresh > 0)
160 		refresh = mode->vrefresh;
161 	else if (mode->htotal > 0 && mode->vtotal > 0) {
162 		/* work out vrefresh the value will be x1000 */
163 		calc_val = (mode->clock * 1000);
164 
165 		calc_val /= mode->htotal;
166 		calc_val *= 1000;
167 		calc_val /= mode->vtotal;
168 
169 		refresh = calc_val;
170 		if (mode->flags & DRM_MODE_FLAG_INTERLACE)
171 			refresh *= 2;
172 		if (mode->flags & DRM_MODE_FLAG_DBLSCAN)
173 			refresh /= 2;
174 		if (mode->vscan > 1)
175 			refresh /= mode->vscan;
176 	}
177 	return refresh;
178 }
179 EXPORT_SYMBOL(drm_mode_vrefresh);
180 
181 /**
182  * drm_mode_set_crtcinfo - set CRTC modesetting parameters
183  * @p: mode
184  * @adjust_flags: unused? (FIXME)
185  *
186  * LOCKING:
187  * None.
188  *
189  * Setup the CRTC modesetting parameters for @p, adjusting if necessary.
190  */
191 void drm_mode_set_crtcinfo(struct drm_display_mode *p, int adjust_flags)
192 {
193 	if ((p == NULL) || ((p->type & DRM_MODE_TYPE_CRTC_C) == DRM_MODE_TYPE_BUILTIN))
194 		return;
195 
196 	p->crtc_hdisplay = p->hdisplay;
197 	p->crtc_hsync_start = p->hsync_start;
198 	p->crtc_hsync_end = p->hsync_end;
199 	p->crtc_htotal = p->htotal;
200 	p->crtc_hskew = p->hskew;
201 	p->crtc_vdisplay = p->vdisplay;
202 	p->crtc_vsync_start = p->vsync_start;
203 	p->crtc_vsync_end = p->vsync_end;
204 	p->crtc_vtotal = p->vtotal;
205 
206 	if (p->flags & DRM_MODE_FLAG_INTERLACE) {
207 		if (adjust_flags & CRTC_INTERLACE_HALVE_V) {
208 			p->crtc_vdisplay /= 2;
209 			p->crtc_vsync_start /= 2;
210 			p->crtc_vsync_end /= 2;
211 			p->crtc_vtotal /= 2;
212 		}
213 
214 		p->crtc_vtotal |= 1;
215 	}
216 
217 	if (p->flags & DRM_MODE_FLAG_DBLSCAN) {
218 		p->crtc_vdisplay *= 2;
219 		p->crtc_vsync_start *= 2;
220 		p->crtc_vsync_end *= 2;
221 		p->crtc_vtotal *= 2;
222 	}
223 
224 	if (p->vscan > 1) {
225 		p->crtc_vdisplay *= p->vscan;
226 		p->crtc_vsync_start *= p->vscan;
227 		p->crtc_vsync_end *= p->vscan;
228 		p->crtc_vtotal *= p->vscan;
229 	}
230 
231 	p->crtc_vblank_start = min(p->crtc_vsync_start, p->crtc_vdisplay);
232 	p->crtc_vblank_end = max(p->crtc_vsync_end, p->crtc_vtotal);
233 	p->crtc_hblank_start = min(p->crtc_hsync_start, p->crtc_hdisplay);
234 	p->crtc_hblank_end = max(p->crtc_hsync_end, p->crtc_htotal);
235 
236 	p->crtc_hadjusted = false;
237 	p->crtc_vadjusted = false;
238 }
239 EXPORT_SYMBOL(drm_mode_set_crtcinfo);
240 
241 
242 /**
243  * drm_mode_duplicate - allocate and duplicate an existing mode
244  * @m: mode to duplicate
245  *
246  * LOCKING:
247  * None.
248  *
249  * Just allocate a new mode, copy the existing mode into it, and return
250  * a pointer to it.  Used to create new instances of established modes.
251  */
252 struct drm_display_mode *drm_mode_duplicate(struct drm_device *dev,
253 					    struct drm_display_mode *mode)
254 {
255 	struct drm_display_mode *nmode;
256 	int new_id;
257 
258 	nmode = drm_mode_create(dev);
259 	if (!nmode)
260 		return NULL;
261 
262 	new_id = nmode->base.id;
263 	*nmode = *mode;
264 	nmode->base.id = new_id;
265 	INIT_LIST_HEAD(&nmode->head);
266 	return nmode;
267 }
268 EXPORT_SYMBOL(drm_mode_duplicate);
269 
270 /**
271  * drm_mode_equal - test modes for equality
272  * @mode1: first mode
273  * @mode2: second mode
274  *
275  * LOCKING:
276  * None.
277  *
278  * Check to see if @mode1 and @mode2 are equivalent.
279  *
280  * RETURNS:
281  * True if the modes are equal, false otherwise.
282  */
283 bool drm_mode_equal(struct drm_display_mode *mode1, struct drm_display_mode *mode2)
284 {
285 	/* do clock check convert to PICOS so fb modes get matched
286 	 * the same */
287 	if (mode1->clock && mode2->clock) {
288 		if (KHZ2PICOS(mode1->clock) != KHZ2PICOS(mode2->clock))
289 			return false;
290 	} else if (mode1->clock != mode2->clock)
291 		return false;
292 
293 	if (mode1->hdisplay == mode2->hdisplay &&
294 	    mode1->hsync_start == mode2->hsync_start &&
295 	    mode1->hsync_end == mode2->hsync_end &&
296 	    mode1->htotal == mode2->htotal &&
297 	    mode1->hskew == mode2->hskew &&
298 	    mode1->vdisplay == mode2->vdisplay &&
299 	    mode1->vsync_start == mode2->vsync_start &&
300 	    mode1->vsync_end == mode2->vsync_end &&
301 	    mode1->vtotal == mode2->vtotal &&
302 	    mode1->vscan == mode2->vscan &&
303 	    mode1->flags == mode2->flags)
304 		return true;
305 
306 	return false;
307 }
308 EXPORT_SYMBOL(drm_mode_equal);
309 
310 /**
311  * drm_mode_validate_size - make sure modes adhere to size constraints
312  * @dev: DRM device
313  * @mode_list: list of modes to check
314  * @maxX: maximum width
315  * @maxY: maximum height
316  * @maxPitch: max pitch
317  *
318  * LOCKING:
319  * Caller must hold a lock protecting @mode_list.
320  *
321  * The DRM device (@dev) has size and pitch limits.  Here we validate the
322  * modes we probed for @dev against those limits and set their status as
323  * necessary.
324  */
325 void drm_mode_validate_size(struct drm_device *dev,
326 			    struct list_head *mode_list,
327 			    int maxX, int maxY, int maxPitch)
328 {
329 	struct drm_display_mode *mode;
330 
331 	list_for_each_entry(mode, mode_list, head) {
332 		if (maxPitch > 0 && mode->hdisplay > maxPitch)
333 			mode->status = MODE_BAD_WIDTH;
334 
335 		if (maxX > 0 && mode->hdisplay > maxX)
336 			mode->status = MODE_VIRTUAL_X;
337 
338 		if (maxY > 0 && mode->vdisplay > maxY)
339 			mode->status = MODE_VIRTUAL_Y;
340 	}
341 }
342 EXPORT_SYMBOL(drm_mode_validate_size);
343 
344 /**
345  * drm_mode_validate_clocks - validate modes against clock limits
346  * @dev: DRM device
347  * @mode_list: list of modes to check
348  * @min: minimum clock rate array
349  * @max: maximum clock rate array
350  * @n_ranges: number of clock ranges (size of arrays)
351  *
352  * LOCKING:
353  * Caller must hold a lock protecting @mode_list.
354  *
355  * Some code may need to check a mode list against the clock limits of the
356  * device in question.  This function walks the mode list, testing to make
357  * sure each mode falls within a given range (defined by @min and @max
358  * arrays) and sets @mode->status as needed.
359  */
360 void drm_mode_validate_clocks(struct drm_device *dev,
361 			      struct list_head *mode_list,
362 			      int *min, int *max, int n_ranges)
363 {
364 	struct drm_display_mode *mode;
365 	int i;
366 
367 	list_for_each_entry(mode, mode_list, head) {
368 		bool good = false;
369 		for (i = 0; i < n_ranges; i++) {
370 			if (mode->clock >= min[i] && mode->clock <= max[i]) {
371 				good = true;
372 				break;
373 			}
374 		}
375 		if (!good)
376 			mode->status = MODE_CLOCK_RANGE;
377 	}
378 }
379 EXPORT_SYMBOL(drm_mode_validate_clocks);
380 
381 /**
382  * drm_mode_prune_invalid - remove invalid modes from mode list
383  * @dev: DRM device
384  * @mode_list: list of modes to check
385  * @verbose: be verbose about it
386  *
387  * LOCKING:
388  * Caller must hold a lock protecting @mode_list.
389  *
390  * Once mode list generation is complete, a caller can use this routine to
391  * remove invalid modes from a mode list.  If any of the modes have a
392  * status other than %MODE_OK, they are removed from @mode_list and freed.
393  */
394 void drm_mode_prune_invalid(struct drm_device *dev,
395 			    struct list_head *mode_list, bool verbose)
396 {
397 	struct drm_display_mode *mode, *t;
398 
399 	list_for_each_entry_safe(mode, t, mode_list, head) {
400 		if (mode->status != MODE_OK) {
401 			list_del(&mode->head);
402 			if (verbose) {
403 				drm_mode_debug_printmodeline(mode);
404 				DRM_DEBUG("Not using %s mode %d\n", mode->name, mode->status);
405 			}
406 			drm_mode_destroy(dev, mode);
407 		}
408 	}
409 }
410 EXPORT_SYMBOL(drm_mode_prune_invalid);
411 
412 /**
413  * drm_mode_compare - compare modes for favorability
414  * @lh_a: list_head for first mode
415  * @lh_b: list_head for second mode
416  *
417  * LOCKING:
418  * None.
419  *
420  * Compare two modes, given by @lh_a and @lh_b, returning a value indicating
421  * which is better.
422  *
423  * RETURNS:
424  * Negative if @lh_a is better than @lh_b, zero if they're equivalent, or
425  * positive if @lh_b is better than @lh_a.
426  */
427 static int drm_mode_compare(struct list_head *lh_a, struct list_head *lh_b)
428 {
429 	struct drm_display_mode *a = list_entry(lh_a, struct drm_display_mode, head);
430 	struct drm_display_mode *b = list_entry(lh_b, struct drm_display_mode, head);
431 	int diff;
432 
433 	diff = ((b->type & DRM_MODE_TYPE_PREFERRED) != 0) -
434 		((a->type & DRM_MODE_TYPE_PREFERRED) != 0);
435 	if (diff)
436 		return diff;
437 	diff = b->hdisplay * b->vdisplay - a->hdisplay * a->vdisplay;
438 	if (diff)
439 		return diff;
440 	diff = b->clock - a->clock;
441 	return diff;
442 }
443 
444 /* FIXME: what we don't have a list sort function? */
445 /* list sort from Mark J Roberts (mjr@znex.org) */
446 void list_sort(struct list_head *head,
447 	       int (*cmp)(struct list_head *a, struct list_head *b))
448 {
449 	struct list_head *p, *q, *e, *list, *tail, *oldhead;
450 	int insize, nmerges, psize, qsize, i;
451 
452 	list = head->next;
453 	list_del(head);
454 	insize = 1;
455 	for (;;) {
456 		p = oldhead = list;
457 		list = tail = NULL;
458 		nmerges = 0;
459 
460 		while (p) {
461 			nmerges++;
462 			q = p;
463 			psize = 0;
464 			for (i = 0; i < insize; i++) {
465 				psize++;
466 				q = q->next == oldhead ? NULL : q->next;
467 				if (!q)
468 					break;
469 			}
470 
471 			qsize = insize;
472 			while (psize > 0 || (qsize > 0 && q)) {
473 				if (!psize) {
474 					e = q;
475 					q = q->next;
476 					qsize--;
477 					if (q == oldhead)
478 						q = NULL;
479 				} else if (!qsize || !q) {
480 					e = p;
481 					p = p->next;
482 					psize--;
483 					if (p == oldhead)
484 						p = NULL;
485 				} else if (cmp(p, q) <= 0) {
486 					e = p;
487 					p = p->next;
488 					psize--;
489 					if (p == oldhead)
490 						p = NULL;
491 				} else {
492 					e = q;
493 					q = q->next;
494 					qsize--;
495 					if (q == oldhead)
496 						q = NULL;
497 				}
498 				if (tail)
499 					tail->next = e;
500 				else
501 					list = e;
502 				e->prev = tail;
503 				tail = e;
504 			}
505 			p = q;
506 		}
507 
508 		tail->next = list;
509 		list->prev = tail;
510 
511 		if (nmerges <= 1)
512 			break;
513 
514 		insize *= 2;
515 	}
516 
517 	head->next = list;
518 	head->prev = list->prev;
519 	list->prev->next = head;
520 	list->prev = head;
521 }
522 
523 /**
524  * drm_mode_sort - sort mode list
525  * @mode_list: list to sort
526  *
527  * LOCKING:
528  * Caller must hold a lock protecting @mode_list.
529  *
530  * Sort @mode_list by favorability, putting good modes first.
531  */
532 void drm_mode_sort(struct list_head *mode_list)
533 {
534 	list_sort(mode_list, drm_mode_compare);
535 }
536 EXPORT_SYMBOL(drm_mode_sort);
537 
538 /**
539  * drm_mode_connector_list_update - update the mode list for the connector
540  * @connector: the connector to update
541  *
542  * LOCKING:
543  * Caller must hold a lock protecting @mode_list.
544  *
545  * This moves the modes from the @connector probed_modes list
546  * to the actual mode list. It compares the probed mode against the current
547  * list and only adds different modes. All modes unverified after this point
548  * will be removed by the prune invalid modes.
549  */
550 void drm_mode_connector_list_update(struct drm_connector *connector)
551 {
552 	struct drm_display_mode *mode;
553 	struct drm_display_mode *pmode, *pt;
554 	int found_it;
555 
556 	list_for_each_entry_safe(pmode, pt, &connector->probed_modes,
557 				 head) {
558 		found_it = 0;
559 		/* go through current modes checking for the new probed mode */
560 		list_for_each_entry(mode, &connector->modes, head) {
561 			if (drm_mode_equal(pmode, mode)) {
562 				found_it = 1;
563 				/* if equal delete the probed mode */
564 				mode->status = pmode->status;
565 				list_del(&pmode->head);
566 				drm_mode_destroy(connector->dev, pmode);
567 				break;
568 			}
569 		}
570 
571 		if (!found_it) {
572 			list_move_tail(&pmode->head, &connector->modes);
573 		}
574 	}
575 }
576 EXPORT_SYMBOL(drm_mode_connector_list_update);
577