xref: /linux/drivers/gpu/drm/drm_modes.c (revision 5bdef865eb358b6f3760e25e591ae115e9eeddef)
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 #define DRM_MODESET_DEBUG	"drm_mode"
42 /**
43  * drm_mode_debug_printmodeline - debug print a mode
44  * @dev: DRM device
45  * @mode: mode to print
46  *
47  * LOCKING:
48  * None.
49  *
50  * Describe @mode using DRM_DEBUG.
51  */
52 void drm_mode_debug_printmodeline(struct drm_display_mode *mode)
53 {
54 	DRM_DEBUG_MODE(DRM_MODESET_DEBUG,
55 		"Modeline %d:\"%s\" %d %d %d %d %d %d %d %d %d %d 0x%x 0x%x\n",
56 		mode->base.id, mode->name, mode->vrefresh, mode->clock,
57 		mode->hdisplay, mode->hsync_start,
58 		mode->hsync_end, mode->htotal,
59 		mode->vdisplay, mode->vsync_start,
60 		mode->vsync_end, mode->vtotal, mode->type, mode->flags);
61 }
62 EXPORT_SYMBOL(drm_mode_debug_printmodeline);
63 
64 /**
65  * drm_mode_set_name - set the name on a mode
66  * @mode: name will be set in this mode
67  *
68  * LOCKING:
69  * None.
70  *
71  * Set the name of @mode to a standard format.
72  */
73 void drm_mode_set_name(struct drm_display_mode *mode)
74 {
75 	snprintf(mode->name, DRM_DISPLAY_MODE_LEN, "%dx%d", mode->hdisplay,
76 		 mode->vdisplay);
77 }
78 EXPORT_SYMBOL(drm_mode_set_name);
79 
80 /**
81  * drm_mode_list_concat - move modes from one list to another
82  * @head: source list
83  * @new: dst list
84  *
85  * LOCKING:
86  * Caller must ensure both lists are locked.
87  *
88  * Move all the modes from @head to @new.
89  */
90 void drm_mode_list_concat(struct list_head *head, struct list_head *new)
91 {
92 
93 	struct list_head *entry, *tmp;
94 
95 	list_for_each_safe(entry, tmp, head) {
96 		list_move_tail(entry, new);
97 	}
98 }
99 EXPORT_SYMBOL(drm_mode_list_concat);
100 
101 /**
102  * drm_mode_width - get the width of a mode
103  * @mode: mode
104  *
105  * LOCKING:
106  * None.
107  *
108  * Return @mode's width (hdisplay) value.
109  *
110  * FIXME: is this needed?
111  *
112  * RETURNS:
113  * @mode->hdisplay
114  */
115 int drm_mode_width(struct drm_display_mode *mode)
116 {
117 	return mode->hdisplay;
118 
119 }
120 EXPORT_SYMBOL(drm_mode_width);
121 
122 /**
123  * drm_mode_height - get the height of a mode
124  * @mode: mode
125  *
126  * LOCKING:
127  * None.
128  *
129  * Return @mode's height (vdisplay) value.
130  *
131  * FIXME: is this needed?
132  *
133  * RETURNS:
134  * @mode->vdisplay
135  */
136 int drm_mode_height(struct drm_display_mode *mode)
137 {
138 	return mode->vdisplay;
139 }
140 EXPORT_SYMBOL(drm_mode_height);
141 
142 /**
143  * drm_mode_vrefresh - get the vrefresh of a mode
144  * @mode: mode
145  *
146  * LOCKING:
147  * None.
148  *
149  * Return @mode's vrefresh rate or calculate it if necessary.
150  *
151  * FIXME: why is this needed?  shouldn't vrefresh be set already?
152  *
153  * RETURNS:
154  * Vertical refresh rate of @mode x 1000. For precision reasons.
155  */
156 int drm_mode_vrefresh(struct drm_display_mode *mode)
157 {
158 	int refresh = 0;
159 	unsigned int calc_val;
160 
161 	if (mode->vrefresh > 0)
162 		refresh = mode->vrefresh;
163 	else if (mode->htotal > 0 && mode->vtotal > 0) {
164 		/* work out vrefresh the value will be x1000 */
165 		calc_val = (mode->clock * 1000);
166 
167 		calc_val /= mode->htotal;
168 		calc_val *= 1000;
169 		calc_val /= mode->vtotal;
170 
171 		refresh = calc_val;
172 		if (mode->flags & DRM_MODE_FLAG_INTERLACE)
173 			refresh *= 2;
174 		if (mode->flags & DRM_MODE_FLAG_DBLSCAN)
175 			refresh /= 2;
176 		if (mode->vscan > 1)
177 			refresh /= mode->vscan;
178 	}
179 	return refresh;
180 }
181 EXPORT_SYMBOL(drm_mode_vrefresh);
182 
183 /**
184  * drm_mode_set_crtcinfo - set CRTC modesetting parameters
185  * @p: mode
186  * @adjust_flags: unused? (FIXME)
187  *
188  * LOCKING:
189  * None.
190  *
191  * Setup the CRTC modesetting parameters for @p, adjusting if necessary.
192  */
193 void drm_mode_set_crtcinfo(struct drm_display_mode *p, int adjust_flags)
194 {
195 	if ((p == NULL) || ((p->type & DRM_MODE_TYPE_CRTC_C) == DRM_MODE_TYPE_BUILTIN))
196 		return;
197 
198 	p->crtc_hdisplay = p->hdisplay;
199 	p->crtc_hsync_start = p->hsync_start;
200 	p->crtc_hsync_end = p->hsync_end;
201 	p->crtc_htotal = p->htotal;
202 	p->crtc_hskew = p->hskew;
203 	p->crtc_vdisplay = p->vdisplay;
204 	p->crtc_vsync_start = p->vsync_start;
205 	p->crtc_vsync_end = p->vsync_end;
206 	p->crtc_vtotal = p->vtotal;
207 
208 	if (p->flags & DRM_MODE_FLAG_INTERLACE) {
209 		if (adjust_flags & CRTC_INTERLACE_HALVE_V) {
210 			p->crtc_vdisplay /= 2;
211 			p->crtc_vsync_start /= 2;
212 			p->crtc_vsync_end /= 2;
213 			p->crtc_vtotal /= 2;
214 		}
215 
216 		p->crtc_vtotal |= 1;
217 	}
218 
219 	if (p->flags & DRM_MODE_FLAG_DBLSCAN) {
220 		p->crtc_vdisplay *= 2;
221 		p->crtc_vsync_start *= 2;
222 		p->crtc_vsync_end *= 2;
223 		p->crtc_vtotal *= 2;
224 	}
225 
226 	if (p->vscan > 1) {
227 		p->crtc_vdisplay *= p->vscan;
228 		p->crtc_vsync_start *= p->vscan;
229 		p->crtc_vsync_end *= p->vscan;
230 		p->crtc_vtotal *= p->vscan;
231 	}
232 
233 	p->crtc_vblank_start = min(p->crtc_vsync_start, p->crtc_vdisplay);
234 	p->crtc_vblank_end = max(p->crtc_vsync_end, p->crtc_vtotal);
235 	p->crtc_hblank_start = min(p->crtc_hsync_start, p->crtc_hdisplay);
236 	p->crtc_hblank_end = max(p->crtc_hsync_end, p->crtc_htotal);
237 
238 	p->crtc_hadjusted = false;
239 	p->crtc_vadjusted = false;
240 }
241 EXPORT_SYMBOL(drm_mode_set_crtcinfo);
242 
243 
244 /**
245  * drm_mode_duplicate - allocate and duplicate an existing mode
246  * @m: mode to duplicate
247  *
248  * LOCKING:
249  * None.
250  *
251  * Just allocate a new mode, copy the existing mode into it, and return
252  * a pointer to it.  Used to create new instances of established modes.
253  */
254 struct drm_display_mode *drm_mode_duplicate(struct drm_device *dev,
255 					    struct drm_display_mode *mode)
256 {
257 	struct drm_display_mode *nmode;
258 	int new_id;
259 
260 	nmode = drm_mode_create(dev);
261 	if (!nmode)
262 		return NULL;
263 
264 	new_id = nmode->base.id;
265 	*nmode = *mode;
266 	nmode->base.id = new_id;
267 	INIT_LIST_HEAD(&nmode->head);
268 	return nmode;
269 }
270 EXPORT_SYMBOL(drm_mode_duplicate);
271 
272 /**
273  * drm_mode_equal - test modes for equality
274  * @mode1: first mode
275  * @mode2: second mode
276  *
277  * LOCKING:
278  * None.
279  *
280  * Check to see if @mode1 and @mode2 are equivalent.
281  *
282  * RETURNS:
283  * True if the modes are equal, false otherwise.
284  */
285 bool drm_mode_equal(struct drm_display_mode *mode1, struct drm_display_mode *mode2)
286 {
287 	/* do clock check convert to PICOS so fb modes get matched
288 	 * the same */
289 	if (mode1->clock && mode2->clock) {
290 		if (KHZ2PICOS(mode1->clock) != KHZ2PICOS(mode2->clock))
291 			return false;
292 	} else if (mode1->clock != mode2->clock)
293 		return false;
294 
295 	if (mode1->hdisplay == mode2->hdisplay &&
296 	    mode1->hsync_start == mode2->hsync_start &&
297 	    mode1->hsync_end == mode2->hsync_end &&
298 	    mode1->htotal == mode2->htotal &&
299 	    mode1->hskew == mode2->hskew &&
300 	    mode1->vdisplay == mode2->vdisplay &&
301 	    mode1->vsync_start == mode2->vsync_start &&
302 	    mode1->vsync_end == mode2->vsync_end &&
303 	    mode1->vtotal == mode2->vtotal &&
304 	    mode1->vscan == mode2->vscan &&
305 	    mode1->flags == mode2->flags)
306 		return true;
307 
308 	return false;
309 }
310 EXPORT_SYMBOL(drm_mode_equal);
311 
312 /**
313  * drm_mode_validate_size - make sure modes adhere to size constraints
314  * @dev: DRM device
315  * @mode_list: list of modes to check
316  * @maxX: maximum width
317  * @maxY: maximum height
318  * @maxPitch: max pitch
319  *
320  * LOCKING:
321  * Caller must hold a lock protecting @mode_list.
322  *
323  * The DRM device (@dev) has size and pitch limits.  Here we validate the
324  * modes we probed for @dev against those limits and set their status as
325  * necessary.
326  */
327 void drm_mode_validate_size(struct drm_device *dev,
328 			    struct list_head *mode_list,
329 			    int maxX, int maxY, int maxPitch)
330 {
331 	struct drm_display_mode *mode;
332 
333 	list_for_each_entry(mode, mode_list, head) {
334 		if (maxPitch > 0 && mode->hdisplay > maxPitch)
335 			mode->status = MODE_BAD_WIDTH;
336 
337 		if (maxX > 0 && mode->hdisplay > maxX)
338 			mode->status = MODE_VIRTUAL_X;
339 
340 		if (maxY > 0 && mode->vdisplay > maxY)
341 			mode->status = MODE_VIRTUAL_Y;
342 	}
343 }
344 EXPORT_SYMBOL(drm_mode_validate_size);
345 
346 /**
347  * drm_mode_validate_clocks - validate modes against clock limits
348  * @dev: DRM device
349  * @mode_list: list of modes to check
350  * @min: minimum clock rate array
351  * @max: maximum clock rate array
352  * @n_ranges: number of clock ranges (size of arrays)
353  *
354  * LOCKING:
355  * Caller must hold a lock protecting @mode_list.
356  *
357  * Some code may need to check a mode list against the clock limits of the
358  * device in question.  This function walks the mode list, testing to make
359  * sure each mode falls within a given range (defined by @min and @max
360  * arrays) and sets @mode->status as needed.
361  */
362 void drm_mode_validate_clocks(struct drm_device *dev,
363 			      struct list_head *mode_list,
364 			      int *min, int *max, int n_ranges)
365 {
366 	struct drm_display_mode *mode;
367 	int i;
368 
369 	list_for_each_entry(mode, mode_list, head) {
370 		bool good = false;
371 		for (i = 0; i < n_ranges; i++) {
372 			if (mode->clock >= min[i] && mode->clock <= max[i]) {
373 				good = true;
374 				break;
375 			}
376 		}
377 		if (!good)
378 			mode->status = MODE_CLOCK_RANGE;
379 	}
380 }
381 EXPORT_SYMBOL(drm_mode_validate_clocks);
382 
383 /**
384  * drm_mode_prune_invalid - remove invalid modes from mode list
385  * @dev: DRM device
386  * @mode_list: list of modes to check
387  * @verbose: be verbose about it
388  *
389  * LOCKING:
390  * Caller must hold a lock protecting @mode_list.
391  *
392  * Once mode list generation is complete, a caller can use this routine to
393  * remove invalid modes from a mode list.  If any of the modes have a
394  * status other than %MODE_OK, they are removed from @mode_list and freed.
395  */
396 void drm_mode_prune_invalid(struct drm_device *dev,
397 			    struct list_head *mode_list, bool verbose)
398 {
399 	struct drm_display_mode *mode, *t;
400 
401 	list_for_each_entry_safe(mode, t, mode_list, head) {
402 		if (mode->status != MODE_OK) {
403 			list_del(&mode->head);
404 			if (verbose) {
405 				drm_mode_debug_printmodeline(mode);
406 				DRM_DEBUG_MODE(DRM_MODESET_DEBUG,
407 					"Not using %s mode %d\n",
408 					mode->name, mode->status);
409 			}
410 			drm_mode_destroy(dev, mode);
411 		}
412 	}
413 }
414 EXPORT_SYMBOL(drm_mode_prune_invalid);
415 
416 /**
417  * drm_mode_compare - compare modes for favorability
418  * @lh_a: list_head for first mode
419  * @lh_b: list_head for second mode
420  *
421  * LOCKING:
422  * None.
423  *
424  * Compare two modes, given by @lh_a and @lh_b, returning a value indicating
425  * which is better.
426  *
427  * RETURNS:
428  * Negative if @lh_a is better than @lh_b, zero if they're equivalent, or
429  * positive if @lh_b is better than @lh_a.
430  */
431 static int drm_mode_compare(struct list_head *lh_a, struct list_head *lh_b)
432 {
433 	struct drm_display_mode *a = list_entry(lh_a, struct drm_display_mode, head);
434 	struct drm_display_mode *b = list_entry(lh_b, struct drm_display_mode, head);
435 	int diff;
436 
437 	diff = ((b->type & DRM_MODE_TYPE_PREFERRED) != 0) -
438 		((a->type & DRM_MODE_TYPE_PREFERRED) != 0);
439 	if (diff)
440 		return diff;
441 	diff = b->hdisplay * b->vdisplay - a->hdisplay * a->vdisplay;
442 	if (diff)
443 		return diff;
444 	diff = b->clock - a->clock;
445 	return diff;
446 }
447 
448 /* FIXME: what we don't have a list sort function? */
449 /* list sort from Mark J Roberts (mjr@znex.org) */
450 void list_sort(struct list_head *head,
451 	       int (*cmp)(struct list_head *a, struct list_head *b))
452 {
453 	struct list_head *p, *q, *e, *list, *tail, *oldhead;
454 	int insize, nmerges, psize, qsize, i;
455 
456 	list = head->next;
457 	list_del(head);
458 	insize = 1;
459 	for (;;) {
460 		p = oldhead = list;
461 		list = tail = NULL;
462 		nmerges = 0;
463 
464 		while (p) {
465 			nmerges++;
466 			q = p;
467 			psize = 0;
468 			for (i = 0; i < insize; i++) {
469 				psize++;
470 				q = q->next == oldhead ? NULL : q->next;
471 				if (!q)
472 					break;
473 			}
474 
475 			qsize = insize;
476 			while (psize > 0 || (qsize > 0 && q)) {
477 				if (!psize) {
478 					e = q;
479 					q = q->next;
480 					qsize--;
481 					if (q == oldhead)
482 						q = NULL;
483 				} else if (!qsize || !q) {
484 					e = p;
485 					p = p->next;
486 					psize--;
487 					if (p == oldhead)
488 						p = NULL;
489 				} else if (cmp(p, q) <= 0) {
490 					e = p;
491 					p = p->next;
492 					psize--;
493 					if (p == oldhead)
494 						p = NULL;
495 				} else {
496 					e = q;
497 					q = q->next;
498 					qsize--;
499 					if (q == oldhead)
500 						q = NULL;
501 				}
502 				if (tail)
503 					tail->next = e;
504 				else
505 					list = e;
506 				e->prev = tail;
507 				tail = e;
508 			}
509 			p = q;
510 		}
511 
512 		tail->next = list;
513 		list->prev = tail;
514 
515 		if (nmerges <= 1)
516 			break;
517 
518 		insize *= 2;
519 	}
520 
521 	head->next = list;
522 	head->prev = list->prev;
523 	list->prev->next = head;
524 	list->prev = head;
525 }
526 
527 /**
528  * drm_mode_sort - sort mode list
529  * @mode_list: list to sort
530  *
531  * LOCKING:
532  * Caller must hold a lock protecting @mode_list.
533  *
534  * Sort @mode_list by favorability, putting good modes first.
535  */
536 void drm_mode_sort(struct list_head *mode_list)
537 {
538 	list_sort(mode_list, drm_mode_compare);
539 }
540 EXPORT_SYMBOL(drm_mode_sort);
541 
542 /**
543  * drm_mode_connector_list_update - update the mode list for the connector
544  * @connector: the connector to update
545  *
546  * LOCKING:
547  * Caller must hold a lock protecting @mode_list.
548  *
549  * This moves the modes from the @connector probed_modes list
550  * to the actual mode list. It compares the probed mode against the current
551  * list and only adds different modes. All modes unverified after this point
552  * will be removed by the prune invalid modes.
553  */
554 void drm_mode_connector_list_update(struct drm_connector *connector)
555 {
556 	struct drm_display_mode *mode;
557 	struct drm_display_mode *pmode, *pt;
558 	int found_it;
559 
560 	list_for_each_entry_safe(pmode, pt, &connector->probed_modes,
561 				 head) {
562 		found_it = 0;
563 		/* go through current modes checking for the new probed mode */
564 		list_for_each_entry(mode, &connector->modes, head) {
565 			if (drm_mode_equal(pmode, mode)) {
566 				found_it = 1;
567 				/* if equal delete the probed mode */
568 				mode->status = pmode->status;
569 				list_del(&pmode->head);
570 				drm_mode_destroy(connector->dev, pmode);
571 				break;
572 			}
573 		}
574 
575 		if (!found_it) {
576 			list_move_tail(&pmode->head, &connector->modes);
577 		}
578 	}
579 }
580 EXPORT_SYMBOL(drm_mode_connector_list_update);
581