xref: /openbmc/linux/drivers/gpu/drm/drm_rect.c (revision 3ac14b39)
1 /*
2  * Copyright (C) 2011-2013 Intel Corporation
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a
5  * copy of this software and associated documentation files (the "Software"),
6  * to deal in the Software without restriction, including without limitation
7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8  * and/or sell copies of the Software, and to permit persons to whom the
9  * Software is furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice (including the next
12  * paragraph) shall be included in all copies or substantial portions of the
13  * Software.
14  *
15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
20  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
21  * SOFTWARE.
22  */
23 
24 #include <linux/errno.h>
25 #include <linux/export.h>
26 #include <linux/kernel.h>
27 #include <drm/drmP.h>
28 #include <drm/drm_rect.h>
29 
30 /**
31  * drm_rect_intersect - intersect two rectangles
32  * @r1: first rectangle
33  * @r2: second rectangle
34  *
35  * Calculate the intersection of rectangles @r1 and @r2.
36  * @r1 will be overwritten with the intersection.
37  *
38  * RETURNS:
39  * %true if rectangle @r1 is still visible after the operation,
40  * %false otherwise.
41  */
42 bool drm_rect_intersect(struct drm_rect *r1, const struct drm_rect *r2)
43 {
44 	r1->x1 = max(r1->x1, r2->x1);
45 	r1->y1 = max(r1->y1, r2->y1);
46 	r1->x2 = min(r1->x2, r2->x2);
47 	r1->y2 = min(r1->y2, r2->y2);
48 
49 	return drm_rect_visible(r1);
50 }
51 EXPORT_SYMBOL(drm_rect_intersect);
52 
53 static u32 clip_scaled(u32 src, u32 dst, u32 clip)
54 {
55 	u64 tmp = mul_u32_u32(src, dst - clip);
56 
57 	/*
58 	 * Round toward 1.0 when clipping so that we don't accidentally
59 	 * change upscaling to downscaling or vice versa.
60 	 */
61 	if (src < (dst << 16))
62 		return DIV_ROUND_UP_ULL(tmp, dst);
63 	else
64 		return DIV_ROUND_DOWN_ULL(tmp, dst);
65 }
66 
67 /**
68  * drm_rect_clip_scaled - perform a scaled clip operation
69  * @src: source window rectangle
70  * @dst: destination window rectangle
71  * @clip: clip rectangle
72  *
73  * Clip rectangle @dst by rectangle @clip. Clip rectangle @src by the
74  * same amounts multiplied by @hscale and @vscale.
75  *
76  * RETURNS:
77  * %true if rectangle @dst is still visible after being clipped,
78  * %false otherwise
79  */
80 bool drm_rect_clip_scaled(struct drm_rect *src, struct drm_rect *dst,
81 			  const struct drm_rect *clip)
82 {
83 	int diff;
84 
85 	diff = clip->x1 - dst->x1;
86 	if (diff > 0) {
87 		u32 new_src_w = clip_scaled(drm_rect_width(src),
88 					    drm_rect_width(dst), diff);
89 
90 		src->x1 = clamp_t(int64_t, src->x2 - new_src_w, INT_MIN, INT_MAX);
91 		dst->x1 = clip->x1;
92 	}
93 	diff = clip->y1 - dst->y1;
94 	if (diff > 0) {
95 		u32 new_src_h = clip_scaled(drm_rect_height(src),
96 					    drm_rect_height(dst), diff);
97 
98 		src->y1 = clamp_t(int64_t, src->y2 - new_src_h, INT_MIN, INT_MAX);
99 		dst->y1 = clip->y1;
100 	}
101 	diff = dst->x2 - clip->x2;
102 	if (diff > 0) {
103 		u32 new_src_w = clip_scaled(drm_rect_width(src),
104 					    drm_rect_width(dst), diff);
105 
106 		src->x2 = clamp_t(int64_t, src->x1 + new_src_w, INT_MIN, INT_MAX);
107 		dst->x2 = clip->x2;
108 	}
109 	diff = dst->y2 - clip->y2;
110 	if (diff > 0) {
111 		u32 new_src_h = clip_scaled(drm_rect_height(src),
112 					    drm_rect_height(dst), diff);
113 
114 		src->y2 = clamp_t(int64_t, src->y1 + new_src_h, INT_MIN, INT_MAX);
115 		dst->y2 = clip->y2;
116 	}
117 
118 	return drm_rect_visible(dst);
119 }
120 EXPORT_SYMBOL(drm_rect_clip_scaled);
121 
122 static int drm_calc_scale(int src, int dst)
123 {
124 	int scale = 0;
125 
126 	if (WARN_ON(src < 0 || dst < 0))
127 		return -EINVAL;
128 
129 	if (dst == 0)
130 		return 0;
131 
132 	if (src > (dst << 16))
133 		return DIV_ROUND_UP(src, dst);
134 	else
135 		scale = src / dst;
136 
137 	return scale;
138 }
139 
140 /**
141  * drm_rect_calc_hscale - calculate the horizontal scaling factor
142  * @src: source window rectangle
143  * @dst: destination window rectangle
144  * @min_hscale: minimum allowed horizontal scaling factor
145  * @max_hscale: maximum allowed horizontal scaling factor
146  *
147  * Calculate the horizontal scaling factor as
148  * (@src width) / (@dst width).
149  *
150  * If the scale is below 1 << 16, round down. If the scale is above
151  * 1 << 16, round up. This will calculate the scale with the most
152  * pessimistic limit calculation.
153  *
154  * RETURNS:
155  * The horizontal scaling factor, or errno of out of limits.
156  */
157 int drm_rect_calc_hscale(const struct drm_rect *src,
158 			 const struct drm_rect *dst,
159 			 int min_hscale, int max_hscale)
160 {
161 	int src_w = drm_rect_width(src);
162 	int dst_w = drm_rect_width(dst);
163 	int hscale = drm_calc_scale(src_w, dst_w);
164 
165 	if (hscale < 0 || dst_w == 0)
166 		return hscale;
167 
168 	if (hscale < min_hscale || hscale > max_hscale)
169 		return -ERANGE;
170 
171 	return hscale;
172 }
173 EXPORT_SYMBOL(drm_rect_calc_hscale);
174 
175 /**
176  * drm_rect_calc_vscale - calculate the vertical scaling factor
177  * @src: source window rectangle
178  * @dst: destination window rectangle
179  * @min_vscale: minimum allowed vertical scaling factor
180  * @max_vscale: maximum allowed vertical scaling factor
181  *
182  * Calculate the vertical scaling factor as
183  * (@src height) / (@dst height).
184  *
185  * If the scale is below 1 << 16, round down. If the scale is above
186  * 1 << 16, round up. This will calculate the scale with the most
187  * pessimistic limit calculation.
188  *
189  * RETURNS:
190  * The vertical scaling factor, or errno of out of limits.
191  */
192 int drm_rect_calc_vscale(const struct drm_rect *src,
193 			 const struct drm_rect *dst,
194 			 int min_vscale, int max_vscale)
195 {
196 	int src_h = drm_rect_height(src);
197 	int dst_h = drm_rect_height(dst);
198 	int vscale = drm_calc_scale(src_h, dst_h);
199 
200 	if (vscale < 0 || dst_h == 0)
201 		return vscale;
202 
203 	if (vscale < min_vscale || vscale > max_vscale)
204 		return -ERANGE;
205 
206 	return vscale;
207 }
208 EXPORT_SYMBOL(drm_rect_calc_vscale);
209 
210 /**
211  * drm_calc_hscale_relaxed - calculate the horizontal scaling factor
212  * @src: source window rectangle
213  * @dst: destination window rectangle
214  * @min_hscale: minimum allowed horizontal scaling factor
215  * @max_hscale: maximum allowed horizontal scaling factor
216  *
217  * Calculate the horizontal scaling factor as
218  * (@src width) / (@dst width).
219  *
220  * If the calculated scaling factor is below @min_vscale,
221  * decrease the height of rectangle @dst to compensate.
222  *
223  * If the calculated scaling factor is above @max_vscale,
224  * decrease the height of rectangle @src to compensate.
225  *
226  * If the scale is below 1 << 16, round down. If the scale is above
227  * 1 << 16, round up. This will calculate the scale with the most
228  * pessimistic limit calculation.
229  *
230  * RETURNS:
231  * The horizontal scaling factor.
232  */
233 int drm_rect_calc_hscale_relaxed(struct drm_rect *src,
234 				 struct drm_rect *dst,
235 				 int min_hscale, int max_hscale)
236 {
237 	int src_w = drm_rect_width(src);
238 	int dst_w = drm_rect_width(dst);
239 	int hscale = drm_calc_scale(src_w, dst_w);
240 
241 	if (hscale < 0 || dst_w == 0)
242 		return hscale;
243 
244 	if (hscale < min_hscale) {
245 		int max_dst_w = src_w / min_hscale;
246 
247 		drm_rect_adjust_size(dst, max_dst_w - dst_w, 0);
248 
249 		return min_hscale;
250 	}
251 
252 	if (hscale > max_hscale) {
253 		int max_src_w = dst_w * max_hscale;
254 
255 		drm_rect_adjust_size(src, max_src_w - src_w, 0);
256 
257 		return max_hscale;
258 	}
259 
260 	return hscale;
261 }
262 EXPORT_SYMBOL(drm_rect_calc_hscale_relaxed);
263 
264 /**
265  * drm_rect_calc_vscale_relaxed - calculate the vertical scaling factor
266  * @src: source window rectangle
267  * @dst: destination window rectangle
268  * @min_vscale: minimum allowed vertical scaling factor
269  * @max_vscale: maximum allowed vertical scaling factor
270  *
271  * Calculate the vertical scaling factor as
272  * (@src height) / (@dst height).
273  *
274  * If the calculated scaling factor is below @min_vscale,
275  * decrease the height of rectangle @dst to compensate.
276  *
277  * If the calculated scaling factor is above @max_vscale,
278  * decrease the height of rectangle @src to compensate.
279  *
280  * If the scale is below 1 << 16, round down. If the scale is above
281  * 1 << 16, round up. This will calculate the scale with the most
282  * pessimistic limit calculation.
283  *
284  * RETURNS:
285  * The vertical scaling factor.
286  */
287 int drm_rect_calc_vscale_relaxed(struct drm_rect *src,
288 				 struct drm_rect *dst,
289 				 int min_vscale, int max_vscale)
290 {
291 	int src_h = drm_rect_height(src);
292 	int dst_h = drm_rect_height(dst);
293 	int vscale = drm_calc_scale(src_h, dst_h);
294 
295 	if (vscale < 0 || dst_h == 0)
296 		return vscale;
297 
298 	if (vscale < min_vscale) {
299 		int max_dst_h = src_h / min_vscale;
300 
301 		drm_rect_adjust_size(dst, 0, max_dst_h - dst_h);
302 
303 		return min_vscale;
304 	}
305 
306 	if (vscale > max_vscale) {
307 		int max_src_h = dst_h * max_vscale;
308 
309 		drm_rect_adjust_size(src, 0, max_src_h - src_h);
310 
311 		return max_vscale;
312 	}
313 
314 	return vscale;
315 }
316 EXPORT_SYMBOL(drm_rect_calc_vscale_relaxed);
317 
318 /**
319  * drm_rect_debug_print - print the rectangle information
320  * @prefix: prefix string
321  * @r: rectangle to print
322  * @fixed_point: rectangle is in 16.16 fixed point format
323  */
324 void drm_rect_debug_print(const char *prefix, const struct drm_rect *r, bool fixed_point)
325 {
326 	if (fixed_point)
327 		DRM_DEBUG_KMS("%s" DRM_RECT_FP_FMT "\n", prefix, DRM_RECT_FP_ARG(r));
328 	else
329 		DRM_DEBUG_KMS("%s" DRM_RECT_FMT "\n", prefix, DRM_RECT_ARG(r));
330 }
331 EXPORT_SYMBOL(drm_rect_debug_print);
332 
333 /**
334  * drm_rect_rotate - Rotate the rectangle
335  * @r: rectangle to be rotated
336  * @width: Width of the coordinate space
337  * @height: Height of the coordinate space
338  * @rotation: Transformation to be applied
339  *
340  * Apply @rotation to the coordinates of rectangle @r.
341  *
342  * @width and @height combined with @rotation define
343  * the location of the new origin.
344  *
345  * @width correcsponds to the horizontal and @height
346  * to the vertical axis of the untransformed coordinate
347  * space.
348  */
349 void drm_rect_rotate(struct drm_rect *r,
350 		     int width, int height,
351 		     unsigned int rotation)
352 {
353 	struct drm_rect tmp;
354 
355 	if (rotation & (DRM_MODE_REFLECT_X | DRM_MODE_REFLECT_Y)) {
356 		tmp = *r;
357 
358 		if (rotation & DRM_MODE_REFLECT_X) {
359 			r->x1 = width - tmp.x2;
360 			r->x2 = width - tmp.x1;
361 		}
362 
363 		if (rotation & DRM_MODE_REFLECT_Y) {
364 			r->y1 = height - tmp.y2;
365 			r->y2 = height - tmp.y1;
366 		}
367 	}
368 
369 	switch (rotation & DRM_MODE_ROTATE_MASK) {
370 	case DRM_MODE_ROTATE_0:
371 		break;
372 	case DRM_MODE_ROTATE_90:
373 		tmp = *r;
374 		r->x1 = tmp.y1;
375 		r->x2 = tmp.y2;
376 		r->y1 = width - tmp.x2;
377 		r->y2 = width - tmp.x1;
378 		break;
379 	case DRM_MODE_ROTATE_180:
380 		tmp = *r;
381 		r->x1 = width - tmp.x2;
382 		r->x2 = width - tmp.x1;
383 		r->y1 = height - tmp.y2;
384 		r->y2 = height - tmp.y1;
385 		break;
386 	case DRM_MODE_ROTATE_270:
387 		tmp = *r;
388 		r->x1 = height - tmp.y2;
389 		r->x2 = height - tmp.y1;
390 		r->y1 = tmp.x1;
391 		r->y2 = tmp.x2;
392 		break;
393 	default:
394 		break;
395 	}
396 }
397 EXPORT_SYMBOL(drm_rect_rotate);
398 
399 /**
400  * drm_rect_rotate_inv - Inverse rotate the rectangle
401  * @r: rectangle to be rotated
402  * @width: Width of the coordinate space
403  * @height: Height of the coordinate space
404  * @rotation: Transformation whose inverse is to be applied
405  *
406  * Apply the inverse of @rotation to the coordinates
407  * of rectangle @r.
408  *
409  * @width and @height combined with @rotation define
410  * the location of the new origin.
411  *
412  * @width correcsponds to the horizontal and @height
413  * to the vertical axis of the original untransformed
414  * coordinate space, so that you never have to flip
415  * them when doing a rotatation and its inverse.
416  * That is, if you do ::
417  *
418  *     drm_rect_rotate(&r, width, height, rotation);
419  *     drm_rect_rotate_inv(&r, width, height, rotation);
420  *
421  * you will always get back the original rectangle.
422  */
423 void drm_rect_rotate_inv(struct drm_rect *r,
424 			 int width, int height,
425 			 unsigned int rotation)
426 {
427 	struct drm_rect tmp;
428 
429 	switch (rotation & DRM_MODE_ROTATE_MASK) {
430 	case DRM_MODE_ROTATE_0:
431 		break;
432 	case DRM_MODE_ROTATE_90:
433 		tmp = *r;
434 		r->x1 = width - tmp.y2;
435 		r->x2 = width - tmp.y1;
436 		r->y1 = tmp.x1;
437 		r->y2 = tmp.x2;
438 		break;
439 	case DRM_MODE_ROTATE_180:
440 		tmp = *r;
441 		r->x1 = width - tmp.x2;
442 		r->x2 = width - tmp.x1;
443 		r->y1 = height - tmp.y2;
444 		r->y2 = height - tmp.y1;
445 		break;
446 	case DRM_MODE_ROTATE_270:
447 		tmp = *r;
448 		r->x1 = tmp.y1;
449 		r->x2 = tmp.y2;
450 		r->y1 = height - tmp.x2;
451 		r->y2 = height - tmp.x1;
452 		break;
453 	default:
454 		break;
455 	}
456 
457 	if (rotation & (DRM_MODE_REFLECT_X | DRM_MODE_REFLECT_Y)) {
458 		tmp = *r;
459 
460 		if (rotation & DRM_MODE_REFLECT_X) {
461 			r->x1 = width - tmp.x2;
462 			r->x2 = width - tmp.x1;
463 		}
464 
465 		if (rotation & DRM_MODE_REFLECT_Y) {
466 			r->y1 = height - tmp.y2;
467 			r->y2 = height - tmp.y1;
468 		}
469 	}
470 }
471 EXPORT_SYMBOL(drm_rect_rotate_inv);
472