xref: /freebsd/sys/dev/videomode/edid.c (revision 3494f7c0)
1 /* $NetBSD: edid.c,v 1.12 2013/02/08 16:35:10 skrll Exp $ */
2 
3 /*-
4  * Copyright (c) 2006 Itronix Inc.
5  * All rights reserved.
6  *
7  * Written by Garrett D'Amore for Itronix Inc.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. The name of Itronix Inc. may not be used to endorse
18  *    or promote products derived from this software without specific
19  *    prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY ITRONIX INC. ``AS IS'' AND ANY EXPRESS
22  * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
23  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL ITRONIX INC. BE LIABLE FOR ANY
25  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
27  * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
28  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
29  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
30  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
31  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 #include <sys/param.h>
35 #include <sys/systm.h>
36 #include <sys/kernel.h>
37 #include <sys/malloc.h>
38 #include <sys/libkern.h>
39 #include <dev/videomode/videomode.h>
40 #include <dev/videomode/ediddevs.h>
41 #include <dev/videomode/edidreg.h>
42 #include <dev/videomode/edidvar.h>
43 #include <dev/videomode/vesagtf.h>
44 
45 #define	EDIDVERBOSE	1
46 #define	DIVIDE(x,y)	(((x) + ((y) / 2)) / (y))
47 
48 /* These are reversed established timing order */
49 static const char *_edid_modes[] =  {
50 	"1280x1024x75",
51 	"1024x768x75",
52 	"1024x768x70",
53 	"1024x768x60",
54 	"1024x768x87i",
55 	"832x624x74",	/* rounding error, 74.55 Hz aka "832x624x75" */
56 	"800x600x75",
57 	"800x600x72",
58 	"800x600x60",
59 	"800x600x56",
60 	"640x480x75",
61 	"640x480x72",
62 	"640x480x67",
63 	"640x480x60",
64 	"720x400x87",	/* rounding error, 87.85 Hz aka "720x400x88" */
65 	"720x400x70",
66 };
67 
68 #ifdef	EDIDVERBOSE
69 struct edid_vendor {
70 	const char	*vendor;
71 	const char	*name;
72 };
73 
74 struct edid_product {
75 	const char	*vendor;
76 	uint16_t	product;
77 	const char	*name;
78 };
79 
80 #include <dev/videomode/ediddevs_data.h>
81 #endif	/* EDIDVERBOSE */
82 
83 static const char *
84 edid_findvendor(const char *vendor)
85 {
86 #ifdef	EDIDVERBOSE
87 	int	n;
88 
89 	for (n = 0; n < edid_nvendors; n++)
90 		if (memcmp(edid_vendors[n].vendor, vendor, 3) == 0)
91 			return edid_vendors[n].name;
92 #endif
93 	return NULL;
94 }
95 
96 static const char *
97 edid_findproduct(const char *vendor, uint16_t product)
98 {
99 #ifdef	EDIDVERBOSE
100 	int	n;
101 
102 	for (n = 0; n < edid_nproducts; n++)
103 		if (edid_products[n].product == product &&
104 		    memcmp(edid_products[n].vendor, vendor, 3) == 0)
105 			return edid_products[n].name;
106 #endif	/* EDIDVERBOSE */
107 	return NULL;
108 
109 }
110 
111 static void
112 edid_strchomp(char *ptr)
113 {
114 	for (;;) {
115 		switch (*ptr) {
116 		case '\0':
117 			return;
118 		case '\r':
119 		case '\n':
120 			*ptr = '\0';
121 			return;
122 		}
123 		ptr++;
124 	}
125 }
126 
127 int
128 edid_is_valid(uint8_t *d)
129 {
130 	int sum = 0, i;
131 	uint8_t sig[8] = EDID_SIGNATURE;
132 
133 	if (memcmp(d, sig, 8) != 0)
134 		return EINVAL;
135 
136 	for (i = 0; i < 128; i++)
137 		sum += d[i];
138 	if ((sum & 0xff) != 0)
139 		return EINVAL;
140 
141 	return 0;
142 }
143 
144 void
145 edid_print(struct edid_info *edid)
146 {
147 	int	i;
148 
149 	if (edid == NULL)
150 		return;
151 	printf("Vendor: [%s] %s\n", edid->edid_vendor, edid->edid_vendorname);
152 	printf("Product: [%04X] %s\n", edid->edid_product,
153 	    edid->edid_productname);
154 	printf("Serial number: %s\n", edid->edid_serial);
155 	printf("Manufactured %d Week %d\n",
156 	    edid->edid_year, edid->edid_week);
157 	printf("EDID Version %d.%d\n", edid->edid_version,
158 	    edid->edid_revision);
159 	printf("EDID Comment: %s\n", edid->edid_comment);
160 
161 	printf("Video Input: %x\n", edid->edid_video_input);
162 	if (edid->edid_video_input & EDID_VIDEO_INPUT_DIGITAL) {
163 		printf("\tDigital");
164 		if (edid->edid_video_input & EDID_VIDEO_INPUT_DFP1_COMPAT)
165 			printf(" (DFP 1.x compatible)");
166 		printf("\n");
167 	} else {
168 		printf("\tAnalog\n");
169 		switch (EDID_VIDEO_INPUT_LEVEL(edid->edid_video_input)) {
170 		case 0:
171 			printf("\t-0.7, 0.3V\n");
172 			break;
173 		case 1:
174 			printf("\t-0.714, 0.286V\n");
175 			break;
176 		case 2:
177 			printf("\t-1.0, 0.4V\n");
178 			break;
179 		case 3:
180 			printf("\t-0.7, 0.0V\n");
181 			break;
182 		}
183 		if (edid->edid_video_input & EDID_VIDEO_INPUT_BLANK_TO_BLACK)
184 			printf("\tBlank-to-black setup\n");
185 		if (edid->edid_video_input & EDID_VIDEO_INPUT_SEPARATE_SYNCS)
186 			printf("\tSeparate syncs\n");
187 		if (edid->edid_video_input & EDID_VIDEO_INPUT_COMPOSITE_SYNC)
188 			printf("\tComposite sync\n");
189 		if (edid->edid_video_input & EDID_VIDEO_INPUT_SYNC_ON_GRN)
190 			printf("\tSync on green\n");
191 		if (edid->edid_video_input & EDID_VIDEO_INPUT_SERRATION)
192 			printf("\tSerration vsync\n");
193 	}
194 
195 	printf("Gamma: %d.%02d\n",
196 	    edid->edid_gamma / 100, edid->edid_gamma % 100);
197 
198 	printf("Max Size: %d cm x %d cm\n",
199 	    edid->edid_max_hsize, edid->edid_max_vsize);
200 
201 	printf("Features: %x\n", edid->edid_features);
202 	if (edid->edid_features & EDID_FEATURES_STANDBY)
203 		printf("\tDPMS standby\n");
204 	if (edid->edid_features & EDID_FEATURES_SUSPEND)
205 		printf("\tDPMS suspend\n");
206 	if (edid->edid_features & EDID_FEATURES_ACTIVE_OFF)
207 		printf("\tDPMS active-off\n");
208 	switch (EDID_FEATURES_DISP_TYPE(edid->edid_features)) {
209 	case EDID_FEATURES_DISP_TYPE_MONO:
210 		printf("\tMonochrome\n");
211 		break;
212 	case EDID_FEATURES_DISP_TYPE_RGB:
213 		printf("\tRGB\n");
214 		break;
215 	case EDID_FEATURES_DISP_TYPE_NON_RGB:
216 		printf("\tMulticolor\n");
217 		break;
218 	case EDID_FEATURES_DISP_TYPE_UNDEFINED:
219 		printf("\tUndefined monitor type\n");
220 		break;
221 	}
222 	if (edid->edid_features & EDID_FEATURES_STD_COLOR)
223 		printf("\tStandard color space\n");
224 	if (edid->edid_features & EDID_FEATURES_PREFERRED_TIMING)
225 		printf("\tPreferred timing\n");
226 	if (edid->edid_features & EDID_FEATURES_DEFAULT_GTF)
227 		printf("\tDefault GTF supported\n");
228 
229 	printf("Chroma Info:\n");
230 	printf("\tRed X: 0.%03d\n", edid->edid_chroma.ec_redx);
231 	printf("\tRed Y: 0.%03d\n", edid->edid_chroma.ec_redy);
232 	printf("\tGrn X: 0.%03d\n", edid->edid_chroma.ec_greenx);
233 	printf("\tGrn Y: 0.%03d\n", edid->edid_chroma.ec_greeny);
234 	printf("\tBlu X: 0.%03d\n", edid->edid_chroma.ec_bluex);
235 	printf("\tBlu Y: 0.%03d\n", edid->edid_chroma.ec_bluey);
236 	printf("\tWht X: 0.%03d\n", edid->edid_chroma.ec_whitex);
237 	printf("\tWht Y: 0.%03d\n", edid->edid_chroma.ec_whitey);
238 
239 	if (edid->edid_have_range) {
240 		printf("Range:\n");
241 		printf("\tHorizontal: %d - %d kHz\n",
242 		    edid->edid_range.er_min_hfreq,
243 		    edid->edid_range.er_max_hfreq);
244 		printf("\tVertical: %d - %d Hz\n",
245 		    edid->edid_range.er_min_vfreq,
246 		    edid->edid_range.er_max_vfreq);
247 		printf("\tMax Dot Clock: %d MHz\n",
248 		    edid->edid_range.er_max_clock);
249 		if (edid->edid_range.er_have_gtf2) {
250 			printf("\tGTF2 hfreq: %d\n",
251 			    edid->edid_range.er_gtf2_hfreq);
252 			printf("\tGTF2 C: %d\n", edid->edid_range.er_gtf2_c);
253 			printf("\tGTF2 M: %d\n", edid->edid_range.er_gtf2_m);
254 			printf("\tGTF2 J: %d\n", edid->edid_range.er_gtf2_j);
255 			printf("\tGTF2 K: %d\n", edid->edid_range.er_gtf2_k);
256 		}
257 	}
258 	printf("Video modes:\n");
259 	for (i = 0; i < edid->edid_nmodes; i++) {
260 		printf("\t%dx%d @ %dHz",
261 		    edid->edid_modes[i].hdisplay,
262 		    edid->edid_modes[i].vdisplay,
263 		    DIVIDE(DIVIDE(edid->edid_modes[i].dot_clock * 1000,
264 		    edid->edid_modes[i].htotal), edid->edid_modes[i].vtotal));
265 		printf(" (%d %d %d %d %d %d %d",
266 		    edid->edid_modes[i].dot_clock,
267 		    edid->edid_modes[i].hsync_start,
268 		    edid->edid_modes[i].hsync_end,
269 		    edid->edid_modes[i].htotal,
270 		    edid->edid_modes[i].vsync_start,
271 		    edid->edid_modes[i].vsync_end,
272 		    edid->edid_modes[i].vtotal);
273 		printf(" %s%sH %s%sV)\n",
274 		    edid->edid_modes[i].flags & VID_PHSYNC ? "+" : "",
275 		    edid->edid_modes[i].flags & VID_NHSYNC ? "-" : "",
276 		    edid->edid_modes[i].flags & VID_PVSYNC ? "+" : "",
277 		    edid->edid_modes[i].flags & VID_NVSYNC ? "-" : "");
278 	}
279 	if (edid->edid_preferred_mode)
280 		printf("Preferred mode: %dx%d @ %dHz\n",
281 		    edid->edid_preferred_mode->hdisplay,
282 		    edid->edid_preferred_mode->vdisplay,
283 		    DIVIDE(DIVIDE(edid->edid_preferred_mode->dot_clock * 1000,
284 		    edid->edid_preferred_mode->htotal),
285 		    edid->edid_preferred_mode->vtotal));
286 
287 	printf("Number of extension blocks: %d\n", edid->edid_ext_block_count);
288 }
289 
290 static const struct videomode *
291 edid_mode_lookup_list(const char *name)
292 {
293 	int	i;
294 
295 	for (i = 0; i < videomode_count; i++)
296 		if (strcmp(name, videomode_list[i].name) == 0)
297 			return &videomode_list[i];
298 	return NULL;
299 }
300 
301 static struct videomode *
302 edid_search_mode(struct edid_info *edid, const struct videomode *mode)
303 {
304 	int	refresh, i;
305 
306 	refresh = DIVIDE(DIVIDE(mode->dot_clock * 1000,
307 	    mode->htotal), mode->vtotal);
308 	for (i = 0; i < edid->edid_nmodes; i++) {
309 		if (mode->hdisplay == edid->edid_modes[i].hdisplay &&
310 		    mode->vdisplay == edid->edid_modes[i].vdisplay &&
311 		    refresh == DIVIDE(DIVIDE(
312 		    edid->edid_modes[i].dot_clock * 1000,
313 		    edid->edid_modes[i].htotal), edid->edid_modes[i].vtotal)) {
314 			return &edid->edid_modes[i];
315 		}
316 	}
317 	return NULL;
318 }
319 
320 static int
321 edid_std_timing(uint8_t *data, struct videomode *vmp)
322 {
323 	unsigned			x, y, f;
324 	const struct videomode		*lookup;
325 	char				name[80];
326 
327 	if ((data[0] == 1 && data[1] == 1) ||
328 	    (data[0] == 0 && data[1] == 0) ||
329 	    (data[0] == 0x20 && data[1] == 0x20))
330 		return 0;
331 
332 	x = EDID_STD_TIMING_HRES(data);
333 	switch (EDID_STD_TIMING_RATIO(data)) {
334 	case EDID_STD_TIMING_RATIO_16_10:
335 		y = x * 10 / 16;
336 		break;
337 	case EDID_STD_TIMING_RATIO_4_3:
338 		y = x * 3 / 4;
339 		break;
340 	case EDID_STD_TIMING_RATIO_5_4:
341 		y = x * 4 / 5;
342 		break;
343 	case EDID_STD_TIMING_RATIO_16_9:
344 	default:
345 		y = x * 9 / 16;
346 		break;
347 	}
348 	f = EDID_STD_TIMING_VFREQ(data);
349 
350 	/* first try to lookup the mode as a DMT timing */
351 	snprintf(name, sizeof(name), "%dx%dx%d", x, y, f);
352 	if ((lookup = edid_mode_lookup_list(name)) != NULL) {
353 		*vmp = *lookup;
354 	} else {
355 		/* failing that, calculate it using gtf */
356 		/*
357 		 * Hmm. I'm not using alternate GTF timings, which
358 		 * could, in theory, be present.
359 		 */
360 		vesagtf_mode(x, y, f, vmp);
361 	}
362 	return 1;
363 }
364 
365 static int
366 edid_det_timing(uint8_t *data, struct videomode *vmp)
367 {
368 	unsigned	hactive, hblank, hsyncwid, hsyncoff;
369 	unsigned	vactive, vblank, vsyncwid, vsyncoff;
370 	uint8_t		flags;
371 
372 	flags = EDID_DET_TIMING_FLAGS(data);
373 
374 	/* we don't support stereo modes (for now) */
375 	if (flags & (EDID_DET_TIMING_FLAG_STEREO |
376 		EDID_DET_TIMING_FLAG_STEREO_MODE))
377 		return 0;
378 
379 	vmp->dot_clock = EDID_DET_TIMING_DOT_CLOCK(data) / 1000;
380 
381 	hactive = EDID_DET_TIMING_HACTIVE(data);
382 	hblank = EDID_DET_TIMING_HBLANK(data);
383 	hsyncwid = EDID_DET_TIMING_HSYNC_WIDTH(data);
384 	hsyncoff = EDID_DET_TIMING_HSYNC_OFFSET(data);
385 
386 	vactive = EDID_DET_TIMING_VACTIVE(data);
387 	vblank = EDID_DET_TIMING_VBLANK(data);
388 	vsyncwid = EDID_DET_TIMING_VSYNC_WIDTH(data);
389 	vsyncoff = EDID_DET_TIMING_VSYNC_OFFSET(data);
390 
391 	/* Borders are contained within the blank areas. */
392 
393 	vmp->hdisplay = hactive;
394 	vmp->htotal = hactive + hblank;
395 	vmp->hsync_start = hactive + hsyncoff;
396 	vmp->hsync_end = vmp->hsync_start + hsyncwid;
397 
398 	vmp->vdisplay = vactive;
399 	vmp->vtotal = vactive + vblank;
400 	vmp->vsync_start = vactive + vsyncoff;
401 	vmp->vsync_end = vmp->vsync_start + vsyncwid;
402 
403 	vmp->flags = 0;
404 
405 	if (flags & EDID_DET_TIMING_FLAG_INTERLACE)
406 		vmp->flags |= VID_INTERLACE;
407 	if (flags & EDID_DET_TIMING_FLAG_HSYNC_POSITIVE)
408 		vmp->flags |= VID_PHSYNC;
409 	else
410 		vmp->flags |= VID_NHSYNC;
411 
412 	if (flags & EDID_DET_TIMING_FLAG_VSYNC_POSITIVE)
413 		vmp->flags |= VID_PVSYNC;
414 	else
415 		vmp->flags |= VID_NVSYNC;
416 
417 	return 1;
418 }
419 
420 static void
421 edid_block(struct edid_info *edid, uint8_t *data)
422 {
423 	int			i;
424 	struct videomode	mode, *exist_mode;
425 
426 	if (EDID_BLOCK_IS_DET_TIMING(data)) {
427 		if (!edid_det_timing(data, &mode))
428 			return;
429 		/* Does this mode already exist? */
430 		exist_mode = edid_search_mode(edid, &mode);
431 		if (exist_mode != NULL) {
432 			*exist_mode = mode;
433 			if (edid->edid_preferred_mode == NULL)
434 				edid->edid_preferred_mode = exist_mode;
435 		} else {
436 			edid->edid_modes[edid->edid_nmodes] = mode;
437 			if (edid->edid_preferred_mode == NULL)
438 				edid->edid_preferred_mode =
439 				    &edid->edid_modes[edid->edid_nmodes];
440 			edid->edid_nmodes++;
441 		}
442 		return;
443 	}
444 
445 	switch (EDID_BLOCK_TYPE(data)) {
446 	case EDID_DESC_BLOCK_TYPE_SERIAL:
447 		memcpy(edid->edid_serial, data + EDID_DESC_ASCII_DATA_OFFSET,
448 		    EDID_DESC_ASCII_DATA_LEN);
449 		edid->edid_serial[sizeof(edid->edid_serial) - 1] = 0;
450 		break;
451 
452 	case EDID_DESC_BLOCK_TYPE_ASCII:
453 		memcpy(edid->edid_comment, data + EDID_DESC_ASCII_DATA_OFFSET,
454 		    EDID_DESC_ASCII_DATA_LEN);
455 		edid->edid_comment[sizeof(edid->edid_comment) - 1] = 0;
456 		break;
457 
458 	case EDID_DESC_BLOCK_TYPE_RANGE:
459 		edid->edid_have_range = 1;
460 		edid->edid_range.er_min_vfreq =	EDID_DESC_RANGE_MIN_VFREQ(data);
461 		edid->edid_range.er_max_vfreq =	EDID_DESC_RANGE_MAX_VFREQ(data);
462 		edid->edid_range.er_min_hfreq =	EDID_DESC_RANGE_MIN_HFREQ(data);
463 		edid->edid_range.er_max_hfreq =	EDID_DESC_RANGE_MAX_HFREQ(data);
464 		edid->edid_range.er_max_clock = EDID_DESC_RANGE_MAX_CLOCK(data);
465 		if (!EDID_DESC_RANGE_HAVE_GTF2(data))
466 			break;
467 		edid->edid_range.er_have_gtf2 = 1;
468 		edid->edid_range.er_gtf2_hfreq =
469 		    EDID_DESC_RANGE_GTF2_HFREQ(data);
470 		edid->edid_range.er_gtf2_c = EDID_DESC_RANGE_GTF2_C(data);
471 		edid->edid_range.er_gtf2_m = EDID_DESC_RANGE_GTF2_M(data);
472 		edid->edid_range.er_gtf2_j = EDID_DESC_RANGE_GTF2_J(data);
473 		edid->edid_range.er_gtf2_k = EDID_DESC_RANGE_GTF2_K(data);
474 		break;
475 
476 	case EDID_DESC_BLOCK_TYPE_NAME:
477 		/* copy the product name into place */
478 		memcpy(edid->edid_productname,
479 		    data + EDID_DESC_ASCII_DATA_OFFSET,
480 		    EDID_DESC_ASCII_DATA_LEN);
481 		break;
482 
483 	case EDID_DESC_BLOCK_TYPE_STD_TIMING:
484 		data += EDID_DESC_STD_TIMING_START;
485 		for (i = 0; i < EDID_DESC_STD_TIMING_COUNT; i++) {
486 			if (edid_std_timing(data, &mode)) {
487 				/* Does this mode already exist? */
488 				exist_mode = edid_search_mode(edid, &mode);
489 				if (exist_mode == NULL) {
490 					edid->edid_modes[edid->edid_nmodes] =
491 					    mode;
492 					edid->edid_nmodes++;
493 				}
494 			}
495 			data += 2;
496 		}
497 		break;
498 
499 	case EDID_DESC_BLOCK_TYPE_COLOR_POINT:
500 		/* XXX: not implemented yet */
501 		break;
502 	}
503 }
504 
505 /*
506  * Gets EDID version in BCD, e.g. EDID v1.3  returned as 0x0103
507  */
508 int
509 edid_parse(uint8_t *data, struct edid_info *edid)
510 {
511 	uint16_t		manfid, estmodes;
512 	const struct videomode	*vmp;
513 	int			i;
514 	const char		*name;
515 	int max_dotclock = 0;
516 	int mhz;
517 
518 	if (edid_is_valid(data) != 0)
519 		return -1;
520 
521 	/* get product identification */
522 	manfid = EDID_VENDOR_ID(data);
523 	edid->edid_vendor[0] = EDID_MANFID_0(manfid);
524 	edid->edid_vendor[1] = EDID_MANFID_1(manfid);
525 	edid->edid_vendor[2] = EDID_MANFID_2(manfid);
526 	edid->edid_vendor[3] = 0;	/* null terminate for convenience */
527 
528 	edid->edid_product = data[EDID_OFFSET_PRODUCT_ID] +
529 	    (data[EDID_OFFSET_PRODUCT_ID + 1] << 8);
530 
531 	name = edid_findvendor(edid->edid_vendor);
532 	if (name != NULL)
533 		strlcpy(edid->edid_vendorname, name,
534 		    sizeof(edid->edid_vendorname));
535 	else
536 		edid->edid_vendorname[0] = '\0';
537 
538 	name = edid_findproduct(edid->edid_vendor, edid->edid_product);
539 	if (name != NULL)
540 		strlcpy(edid->edid_productname, name,
541 		    sizeof(edid->edid_productname));
542 	else
543 	    edid->edid_productname[0] = '\0';
544 
545 	snprintf(edid->edid_serial, sizeof(edid->edid_serial), "%08x",
546 	    EDID_SERIAL_NUMBER(data));
547 
548 	edid->edid_week = EDID_WEEK(data);
549 	edid->edid_year = EDID_YEAR(data);
550 
551 	/* get edid revision */
552 	edid->edid_version = EDID_VERSION(data);
553 	edid->edid_revision = EDID_REVISION(data);
554 
555 	edid->edid_video_input = EDID_VIDEO_INPUT(data);
556 	edid->edid_max_hsize = EDID_MAX_HSIZE(data);
557 	edid->edid_max_vsize = EDID_MAX_VSIZE(data);
558 
559 	edid->edid_gamma = EDID_GAMMA(data);
560 	edid->edid_features = EDID_FEATURES(data);
561 
562 	edid->edid_chroma.ec_redx = EDID_CHROMA_REDX(data);
563 	edid->edid_chroma.ec_redy = EDID_CHROMA_REDX(data);
564 	edid->edid_chroma.ec_greenx = EDID_CHROMA_GREENX(data);
565 	edid->edid_chroma.ec_greeny = EDID_CHROMA_GREENY(data);
566 	edid->edid_chroma.ec_bluex = EDID_CHROMA_BLUEX(data);
567 	edid->edid_chroma.ec_bluey = EDID_CHROMA_BLUEY(data);
568 	edid->edid_chroma.ec_whitex = EDID_CHROMA_WHITEX(data);
569 	edid->edid_chroma.ec_whitey = EDID_CHROMA_WHITEY(data);
570 
571 	edid->edid_ext_block_count = EDID_EXT_BLOCK_COUNT(data);
572 
573 	/* lookup established modes */
574 	edid->edid_nmodes = 0;
575 	edid->edid_preferred_mode = NULL;
576 	estmodes = EDID_EST_TIMING(data);
577 	/* Iterate in esztablished timing order */
578 	for (i = 15; i >= 0; i--) {
579 		if (estmodes & (1 << i)) {
580 			vmp = edid_mode_lookup_list(_edid_modes[i]);
581 			if (vmp != NULL) {
582 				edid->edid_modes[edid->edid_nmodes] = *vmp;
583 				edid->edid_nmodes++;
584 			}
585 #ifdef DIAGNOSTIC
586 			  else
587 				printf("no data for est. mode %s\n",
588 				    _edid_modes[i]);
589 #endif
590 		}
591 	}
592 
593 	/* do standard timing section */
594 	for (i = 0; i < EDID_STD_TIMING_COUNT; i++) {
595 		struct videomode	mode, *exist_mode;
596 		if (edid_std_timing(data + EDID_OFFSET_STD_TIMING + i * 2,
597 			&mode)) {
598 			/* Does this mode already exist? */
599 			exist_mode = edid_search_mode(edid, &mode);
600 			if (exist_mode == NULL) {
601 				edid->edid_modes[edid->edid_nmodes] = mode;
602 				edid->edid_nmodes++;
603 			}
604 		}
605 	}
606 
607 	/* do detailed timings and descriptors */
608 	for (i = 0; i < EDID_BLOCK_COUNT; i++) {
609 		edid_block(edid, data + EDID_OFFSET_DESC_BLOCK +
610 		    i * EDID_BLOCK_SIZE);
611 	}
612 
613 	edid_strchomp(edid->edid_vendorname);
614 	edid_strchomp(edid->edid_productname);
615 	edid_strchomp(edid->edid_serial);
616 	edid_strchomp(edid->edid_comment);
617 
618 	/*
619 	 * XXX
620 	 * some monitors lie about their maximum supported dot clock
621 	 * by claiming to support modes which need a higher dot clock
622 	 * than the stated maximum.
623 	 * For sanity's sake we bump it to the highest dot clock we find
624 	 * in the list of supported modes
625 	 */
626 	for (i = 0; i < edid->edid_nmodes; i++)
627 		if (edid->edid_modes[i].dot_clock > max_dotclock)
628 			max_dotclock = edid->edid_modes[i].dot_clock;
629 	if (bootverbose) {
630 		printf("edid: max_dotclock according to supported modes: %d\n",
631 		    max_dotclock);
632 	}
633 	mhz = (max_dotclock + 999) / 1000;
634 
635 	if (edid->edid_have_range) {
636 		if (mhz > edid->edid_range.er_max_clock)
637 			edid->edid_range.er_max_clock = mhz;
638 	} else
639 		edid->edid_range.er_max_clock = mhz;
640 
641 	return 0;
642 }
643