xref: /dragonfly/sys/dev/drm/i915/intel_bios.c (revision 23b3ef78)
1 /*
2  * Copyright © 2006 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  * Authors:
24  *    Eric Anholt <eric@anholt.net>
25  *
26  */
27 #include <linux/dmi.h>
28 #include <drm/drmP.h>
29 #include <drm/drm_dp_helper.h>
30 #include <drm/i915_drm.h>
31 #include "i915_drv.h"
32 #include "intel_bios.h"
33 #include <linux/string.h>
34 
35 #define	SLAVE_ADDR1	0x70
36 #define	SLAVE_ADDR2	0x72
37 
38 static int panel_type;
39 
40 static void *
41 find_section(struct bdb_header *bdb, int section_id)
42 {
43 	u8 *base = (u8 *)bdb;
44 	int index = 0;
45 	u16 total, current_size;
46 	u8 current_id;
47 
48 	/* skip to first section */
49 	index += bdb->header_size;
50 	total = bdb->bdb_size;
51 
52 	/* walk the sections looking for section_id */
53 	while (index + 3 < total) {
54 		current_id = *(base + index);
55 		index++;
56 
57 		current_size = *((u16 *)(base + index));
58 		index += 2;
59 
60 		if (index + current_size > total)
61 			return NULL;
62 
63 		if (current_id == section_id)
64 			return base + index;
65 
66 		index += current_size;
67 	}
68 
69 	return NULL;
70 }
71 
72 static u16
73 get_blocksize(void *p)
74 {
75 	u16 *block_ptr, block_size;
76 
77 	block_ptr = (u16 *)((char *)p - 2);
78 	block_size = *block_ptr;
79 	return block_size;
80 }
81 
82 static void
83 fill_detail_timing_data(struct drm_display_mode *panel_fixed_mode,
84 			const struct lvds_dvo_timing *dvo_timing)
85 {
86 	panel_fixed_mode->hdisplay = (dvo_timing->hactive_hi << 8) |
87 		dvo_timing->hactive_lo;
88 	panel_fixed_mode->hsync_start = panel_fixed_mode->hdisplay +
89 		((dvo_timing->hsync_off_hi << 8) | dvo_timing->hsync_off_lo);
90 	panel_fixed_mode->hsync_end = panel_fixed_mode->hsync_start +
91 		dvo_timing->hsync_pulse_width;
92 	panel_fixed_mode->htotal = panel_fixed_mode->hdisplay +
93 		((dvo_timing->hblank_hi << 8) | dvo_timing->hblank_lo);
94 
95 	panel_fixed_mode->vdisplay = (dvo_timing->vactive_hi << 8) |
96 		dvo_timing->vactive_lo;
97 	panel_fixed_mode->vsync_start = panel_fixed_mode->vdisplay +
98 		dvo_timing->vsync_off;
99 	panel_fixed_mode->vsync_end = panel_fixed_mode->vsync_start +
100 		dvo_timing->vsync_pulse_width;
101 	panel_fixed_mode->vtotal = panel_fixed_mode->vdisplay +
102 		((dvo_timing->vblank_hi << 8) | dvo_timing->vblank_lo);
103 	panel_fixed_mode->clock = dvo_timing->clock * 10;
104 	panel_fixed_mode->type = DRM_MODE_TYPE_PREFERRED;
105 
106 	if (dvo_timing->hsync_positive)
107 		panel_fixed_mode->flags |= DRM_MODE_FLAG_PHSYNC;
108 	else
109 		panel_fixed_mode->flags |= DRM_MODE_FLAG_NHSYNC;
110 
111 	if (dvo_timing->vsync_positive)
112 		panel_fixed_mode->flags |= DRM_MODE_FLAG_PVSYNC;
113 	else
114 		panel_fixed_mode->flags |= DRM_MODE_FLAG_NVSYNC;
115 
116 	/* Some VBTs have bogus h/vtotal values */
117 	if (panel_fixed_mode->hsync_end > panel_fixed_mode->htotal)
118 		panel_fixed_mode->htotal = panel_fixed_mode->hsync_end + 1;
119 	if (panel_fixed_mode->vsync_end > panel_fixed_mode->vtotal)
120 		panel_fixed_mode->vtotal = panel_fixed_mode->vsync_end + 1;
121 
122 	drm_mode_set_name(panel_fixed_mode);
123 }
124 
125 static bool
126 lvds_dvo_timing_equal_size(const struct lvds_dvo_timing *a,
127 			   const struct lvds_dvo_timing *b)
128 {
129 	if (a->hactive_hi != b->hactive_hi ||
130 	    a->hactive_lo != b->hactive_lo)
131 		return false;
132 
133 	if (a->hsync_off_hi != b->hsync_off_hi ||
134 	    a->hsync_off_lo != b->hsync_off_lo)
135 		return false;
136 
137 	if (a->hsync_pulse_width != b->hsync_pulse_width)
138 		return false;
139 
140 	if (a->hblank_hi != b->hblank_hi ||
141 	    a->hblank_lo != b->hblank_lo)
142 		return false;
143 
144 	if (a->vactive_hi != b->vactive_hi ||
145 	    a->vactive_lo != b->vactive_lo)
146 		return false;
147 
148 	if (a->vsync_off != b->vsync_off)
149 		return false;
150 
151 	if (a->vsync_pulse_width != b->vsync_pulse_width)
152 		return false;
153 
154 	if (a->vblank_hi != b->vblank_hi ||
155 	    a->vblank_lo != b->vblank_lo)
156 		return false;
157 
158 	return true;
159 }
160 
161 static const struct lvds_dvo_timing *
162 get_lvds_dvo_timing(const struct bdb_lvds_lfp_data *lvds_lfp_data,
163 		    const struct bdb_lvds_lfp_data_ptrs *lvds_lfp_data_ptrs,
164 		    int index)
165 {
166 	/*
167 	 * the size of fp_timing varies on the different platform.
168 	 * So calculate the DVO timing relative offset in LVDS data
169 	 * entry to get the DVO timing entry
170 	 */
171 
172 	int lfp_data_size =
173 		lvds_lfp_data_ptrs->ptr[1].dvo_timing_offset -
174 		lvds_lfp_data_ptrs->ptr[0].dvo_timing_offset;
175 	int dvo_timing_offset =
176 		lvds_lfp_data_ptrs->ptr[0].dvo_timing_offset -
177 		lvds_lfp_data_ptrs->ptr[0].fp_timing_offset;
178 	const char *entry = (const char *)lvds_lfp_data->data + lfp_data_size * index;
179 
180 	return (const struct lvds_dvo_timing *)(entry + dvo_timing_offset);
181 }
182 
183 /* get lvds_fp_timing entry
184  * this function may return NULL if the corresponding entry is invalid
185  */
186 static const struct lvds_fp_timing *
187 get_lvds_fp_timing(const struct bdb_header *bdb,
188 		   const struct bdb_lvds_lfp_data *data,
189 		   const struct bdb_lvds_lfp_data_ptrs *ptrs,
190 		   int index)
191 {
192 	size_t data_ofs = (const u8 *)data - (const u8 *)bdb;
193 	u16 data_size = ((const u16 *)data)[-1]; /* stored in header */
194 	size_t ofs;
195 
196 	if (index >= ARRAY_SIZE(ptrs->ptr))
197 		return NULL;
198 	ofs = ptrs->ptr[index].fp_timing_offset;
199 	if (ofs < data_ofs ||
200 	    ofs + sizeof(struct lvds_fp_timing) > data_ofs + data_size)
201 		return NULL;
202 	return (const struct lvds_fp_timing *)((const u8 *)bdb + ofs);
203 }
204 
205 /* Try to find integrated panel data */
206 static void
207 parse_lfp_panel_data(struct drm_i915_private *dev_priv,
208 			    struct bdb_header *bdb)
209 {
210 	const struct bdb_lvds_options *lvds_options;
211 	const struct bdb_lvds_lfp_data *lvds_lfp_data;
212 	const struct bdb_lvds_lfp_data_ptrs *lvds_lfp_data_ptrs;
213 	const struct lvds_dvo_timing *panel_dvo_timing;
214 	const struct lvds_fp_timing *fp_timing;
215 	struct drm_display_mode *panel_fixed_mode;
216 	int i, downclock, drrs_mode;
217 
218 	lvds_options = find_section(bdb, BDB_LVDS_OPTIONS);
219 	if (!lvds_options)
220 		return;
221 
222 	dev_priv->vbt.lvds_dither = lvds_options->pixel_dither;
223 	if (lvds_options->panel_type == 0xff)
224 		return;
225 
226 	panel_type = lvds_options->panel_type;
227 
228 	drrs_mode = (lvds_options->dps_panel_type_bits
229 				>> (panel_type * 2)) & MODE_MASK;
230 	/*
231 	 * VBT has static DRRS = 0 and seamless DRRS = 2.
232 	 * The below piece of code is required to adjust vbt.drrs_type
233 	 * to match the enum drrs_support_type.
234 	 */
235 	switch (drrs_mode) {
236 	case 0:
237 		dev_priv->vbt.drrs_type = STATIC_DRRS_SUPPORT;
238 		DRM_DEBUG_KMS("DRRS supported mode is static\n");
239 		break;
240 	case 2:
241 		dev_priv->vbt.drrs_type = SEAMLESS_DRRS_SUPPORT;
242 		DRM_DEBUG_KMS("DRRS supported mode is seamless\n");
243 		break;
244 	default:
245 		dev_priv->vbt.drrs_type = DRRS_NOT_SUPPORTED;
246 		DRM_DEBUG_KMS("DRRS not supported (VBT input)\n");
247 		break;
248 	}
249 
250 	lvds_lfp_data = find_section(bdb, BDB_LVDS_LFP_DATA);
251 	if (!lvds_lfp_data)
252 		return;
253 
254 	lvds_lfp_data_ptrs = find_section(bdb, BDB_LVDS_LFP_DATA_PTRS);
255 	if (!lvds_lfp_data_ptrs)
256 		return;
257 
258 	dev_priv->vbt.lvds_vbt = 1;
259 
260 	panel_dvo_timing = get_lvds_dvo_timing(lvds_lfp_data,
261 					       lvds_lfp_data_ptrs,
262 					       lvds_options->panel_type);
263 
264 	panel_fixed_mode = kzalloc(sizeof(*panel_fixed_mode), GFP_KERNEL);
265 	if (!panel_fixed_mode)
266 		return;
267 
268 	fill_detail_timing_data(panel_fixed_mode, panel_dvo_timing);
269 
270 	dev_priv->vbt.lfp_lvds_vbt_mode = panel_fixed_mode;
271 
272 	DRM_DEBUG_KMS("Found panel mode in BIOS VBT tables:\n");
273 	drm_mode_debug_printmodeline(panel_fixed_mode);
274 
275 	/*
276 	 * Iterate over the LVDS panel timing info to find the lowest clock
277 	 * for the native resolution.
278 	 */
279 	downclock = panel_dvo_timing->clock;
280 	for (i = 0; i < 16; i++) {
281 		const struct lvds_dvo_timing *dvo_timing;
282 
283 		dvo_timing = get_lvds_dvo_timing(lvds_lfp_data,
284 						 lvds_lfp_data_ptrs,
285 						 i);
286 		if (lvds_dvo_timing_equal_size(dvo_timing, panel_dvo_timing) &&
287 		    dvo_timing->clock < downclock)
288 			downclock = dvo_timing->clock;
289 	}
290 
291 	if (downclock < panel_dvo_timing->clock && i915.lvds_downclock) {
292 		dev_priv->lvds_downclock_avail = 1;
293 		dev_priv->lvds_downclock = downclock * 10;
294 		DRM_DEBUG_KMS("LVDS downclock is found in VBT. "
295 			      "Normal Clock %dKHz, downclock %dKHz\n",
296 			      panel_fixed_mode->clock, 10*downclock);
297 	}
298 
299 	fp_timing = get_lvds_fp_timing(bdb, lvds_lfp_data,
300 				       lvds_lfp_data_ptrs,
301 				       lvds_options->panel_type);
302 	if (fp_timing) {
303 		/* check the resolution, just to be sure */
304 		if (fp_timing->x_res == panel_fixed_mode->hdisplay &&
305 		    fp_timing->y_res == panel_fixed_mode->vdisplay) {
306 			dev_priv->vbt.bios_lvds_val = fp_timing->lvds_reg_val;
307 			DRM_DEBUG_KMS("VBT initial LVDS value %x\n",
308 				      dev_priv->vbt.bios_lvds_val);
309 		}
310 	}
311 }
312 
313 static void
314 parse_lfp_backlight(struct drm_i915_private *dev_priv, struct bdb_header *bdb)
315 {
316 	const struct bdb_lfp_backlight_data *backlight_data;
317 	const struct bdb_lfp_backlight_data_entry *entry;
318 
319 	backlight_data = find_section(bdb, BDB_LVDS_BACKLIGHT);
320 	if (!backlight_data)
321 		return;
322 
323 	if (backlight_data->entry_size != sizeof(backlight_data->data[0])) {
324 		DRM_DEBUG_KMS("Unsupported backlight data entry size %u\n",
325 			      backlight_data->entry_size);
326 		return;
327 	}
328 
329 	entry = &backlight_data->data[panel_type];
330 
331 	dev_priv->vbt.backlight.present = entry->type == BDB_BACKLIGHT_TYPE_PWM;
332 	if (!dev_priv->vbt.backlight.present) {
333 		DRM_DEBUG_KMS("PWM backlight not present in VBT (type %u)\n",
334 			      entry->type);
335 		return;
336 	}
337 
338 	dev_priv->vbt.backlight.pwm_freq_hz = entry->pwm_freq_hz;
339 	dev_priv->vbt.backlight.active_low_pwm = entry->active_low_pwm;
340 	dev_priv->vbt.backlight.min_brightness = entry->min_brightness;
341 	DRM_DEBUG_KMS("VBT backlight PWM modulation frequency %u Hz, "
342 		      "active %s, min brightness %u, level %u\n",
343 		      dev_priv->vbt.backlight.pwm_freq_hz,
344 		      dev_priv->vbt.backlight.active_low_pwm ? "low" : "high",
345 		      dev_priv->vbt.backlight.min_brightness,
346 		      backlight_data->level[panel_type]);
347 }
348 
349 /* Try to find sdvo panel data */
350 static void
351 parse_sdvo_panel_data(struct drm_i915_private *dev_priv,
352 		      struct bdb_header *bdb)
353 {
354 	struct lvds_dvo_timing *dvo_timing;
355 	struct drm_display_mode *panel_fixed_mode;
356 	int index;
357 
358 	index = i915.vbt_sdvo_panel_type;
359 	if (index == -2) {
360 		DRM_DEBUG_KMS("Ignore SDVO panel mode from BIOS VBT tables.\n");
361 		return;
362 	}
363 
364 	if (index == -1) {
365 		struct bdb_sdvo_lvds_options *sdvo_lvds_options;
366 
367 		sdvo_lvds_options = find_section(bdb, BDB_SDVO_LVDS_OPTIONS);
368 		if (!sdvo_lvds_options)
369 			return;
370 
371 		index = sdvo_lvds_options->panel_type;
372 	}
373 
374 	dvo_timing = find_section(bdb, BDB_SDVO_PANEL_DTDS);
375 	if (!dvo_timing)
376 		return;
377 
378 	panel_fixed_mode = kzalloc(sizeof(*panel_fixed_mode), GFP_KERNEL);
379 	if (!panel_fixed_mode)
380 		return;
381 
382 	fill_detail_timing_data(panel_fixed_mode, dvo_timing + index);
383 
384 	dev_priv->vbt.sdvo_lvds_vbt_mode = panel_fixed_mode;
385 
386 	DRM_DEBUG_KMS("Found SDVO panel mode in BIOS VBT tables:\n");
387 	drm_mode_debug_printmodeline(panel_fixed_mode);
388 }
389 
390 static int intel_bios_ssc_frequency(struct drm_device *dev,
391 				    bool alternate)
392 {
393 	switch (INTEL_INFO(dev)->gen) {
394 	case 2:
395 		return alternate ? 66667 : 48000;
396 	case 3:
397 	case 4:
398 		return alternate ? 100000 : 96000;
399 	default:
400 		return alternate ? 100000 : 120000;
401 	}
402 }
403 
404 static void
405 parse_general_features(struct drm_i915_private *dev_priv,
406 		       struct bdb_header *bdb)
407 {
408 	struct drm_device *dev = dev_priv->dev;
409 	struct bdb_general_features *general;
410 
411 	general = find_section(bdb, BDB_GENERAL_FEATURES);
412 	if (general) {
413 		dev_priv->vbt.int_tv_support = general->int_tv_support;
414 		dev_priv->vbt.int_crt_support = general->int_crt_support;
415 		dev_priv->vbt.lvds_use_ssc = general->enable_ssc;
416 		dev_priv->vbt.lvds_ssc_freq =
417 			intel_bios_ssc_frequency(dev, general->ssc_freq);
418 		dev_priv->vbt.display_clock_mode = general->display_clock_mode;
419 		dev_priv->vbt.fdi_rx_polarity_inverted = general->fdi_rx_polarity_inverted;
420 		DRM_DEBUG_KMS("BDB_GENERAL_FEATURES int_tv_support %d int_crt_support %d lvds_use_ssc %d lvds_ssc_freq %d display_clock_mode %d fdi_rx_polarity_inverted %d\n",
421 			      dev_priv->vbt.int_tv_support,
422 			      dev_priv->vbt.int_crt_support,
423 			      dev_priv->vbt.lvds_use_ssc,
424 			      dev_priv->vbt.lvds_ssc_freq,
425 			      dev_priv->vbt.display_clock_mode,
426 			      dev_priv->vbt.fdi_rx_polarity_inverted);
427 	}
428 }
429 
430 static void
431 parse_general_definitions(struct drm_i915_private *dev_priv,
432 			  struct bdb_header *bdb)
433 {
434 	struct bdb_general_definitions *general;
435 
436 	general = find_section(bdb, BDB_GENERAL_DEFINITIONS);
437 	if (general) {
438 		u16 block_size = get_blocksize(general);
439 		if (block_size >= sizeof(*general)) {
440 			int bus_pin = general->crt_ddc_gmbus_pin;
441 			DRM_DEBUG_KMS("crt_ddc_bus_pin: %d\n", bus_pin);
442 			if (intel_gmbus_is_port_valid(bus_pin))
443 				dev_priv->vbt.crt_ddc_pin = bus_pin;
444 		} else {
445 			DRM_DEBUG_KMS("BDB_GD too small (%d). Invalid.\n",
446 				      block_size);
447 		}
448 	}
449 }
450 
451 static void
452 parse_sdvo_device_mapping(struct drm_i915_private *dev_priv,
453 			  struct bdb_header *bdb)
454 {
455 	struct sdvo_device_mapping *p_mapping;
456 	struct bdb_general_definitions *p_defs;
457 	union child_device_config *p_child;
458 	int i, child_device_num, count;
459 	u16	block_size;
460 
461 	p_defs = find_section(bdb, BDB_GENERAL_DEFINITIONS);
462 	if (!p_defs) {
463 		DRM_DEBUG_KMS("No general definition block is found, unable to construct sdvo mapping.\n");
464 		return;
465 	}
466 	/* judge whether the size of child device meets the requirements.
467 	 * If the child device size obtained from general definition block
468 	 * is different with sizeof(struct child_device_config), skip the
469 	 * parsing of sdvo device info
470 	 */
471 	if (p_defs->child_dev_size != sizeof(*p_child)) {
472 		/* different child dev size . Ignore it */
473 		DRM_DEBUG_KMS("different child size is found. Invalid.\n");
474 		return;
475 	}
476 	/* get the block size of general definitions */
477 	block_size = get_blocksize(p_defs);
478 	/* get the number of child device */
479 	child_device_num = (block_size - sizeof(*p_defs)) /
480 				sizeof(*p_child);
481 	count = 0;
482 	for (i = 0; i < child_device_num; i++) {
483 		p_child = &(p_defs->devices[i]);
484 		if (!p_child->old.device_type) {
485 			/* skip the device block if device type is invalid */
486 			continue;
487 		}
488 		if (p_child->old.slave_addr != SLAVE_ADDR1 &&
489 			p_child->old.slave_addr != SLAVE_ADDR2) {
490 			/*
491 			 * If the slave address is neither 0x70 nor 0x72,
492 			 * it is not a SDVO device. Skip it.
493 			 */
494 			continue;
495 		}
496 		if (p_child->old.dvo_port != DEVICE_PORT_DVOB &&
497 			p_child->old.dvo_port != DEVICE_PORT_DVOC) {
498 			/* skip the incorrect SDVO port */
499 			DRM_DEBUG_KMS("Incorrect SDVO port. Skip it\n");
500 			continue;
501 		}
502 		DRM_DEBUG_KMS("the SDVO device with slave addr %2x is found on"
503 				" %s port\n",
504 				p_child->old.slave_addr,
505 				(p_child->old.dvo_port == DEVICE_PORT_DVOB) ?
506 					"SDVOB" : "SDVOC");
507 		p_mapping = &(dev_priv->sdvo_mappings[p_child->old.dvo_port - 1]);
508 		if (!p_mapping->initialized) {
509 			p_mapping->dvo_port = p_child->old.dvo_port;
510 			p_mapping->slave_addr = p_child->old.slave_addr;
511 			p_mapping->dvo_wiring = p_child->old.dvo_wiring;
512 			p_mapping->ddc_pin = p_child->old.ddc_pin;
513 			p_mapping->i2c_pin = p_child->old.i2c_pin;
514 			p_mapping->initialized = 1;
515 			DRM_DEBUG_KMS("SDVO device: dvo=%x, addr=%x, wiring=%d, ddc_pin=%d, i2c_pin=%d\n",
516 				      p_mapping->dvo_port,
517 				      p_mapping->slave_addr,
518 				      p_mapping->dvo_wiring,
519 				      p_mapping->ddc_pin,
520 				      p_mapping->i2c_pin);
521 		} else {
522 			DRM_DEBUG_KMS("Maybe one SDVO port is shared by "
523 					 "two SDVO device.\n");
524 		}
525 		if (p_child->old.slave2_addr) {
526 			/* Maybe this is a SDVO device with multiple inputs */
527 			/* And the mapping info is not added */
528 			DRM_DEBUG_KMS("there exists the slave2_addr. Maybe this"
529 				" is a SDVO device with multiple inputs.\n");
530 		}
531 		count++;
532 	}
533 
534 	if (!count) {
535 		/* No SDVO device info is found */
536 		DRM_DEBUG_KMS("No SDVO device info is found in VBT\n");
537 	}
538 	return;
539 }
540 
541 static void
542 parse_driver_features(struct drm_i915_private *dev_priv,
543 		       struct bdb_header *bdb)
544 {
545 	struct bdb_driver_features *driver;
546 
547 	driver = find_section(bdb, BDB_DRIVER_FEATURES);
548 	if (!driver)
549 		return;
550 
551 	if (driver->lvds_config == BDB_DRIVER_FEATURE_EDP)
552 		dev_priv->vbt.edp_support = 1;
553 
554 	if (driver->dual_frequency)
555 		dev_priv->render_reclock_avail = true;
556 
557 	DRM_DEBUG_KMS("DRRS State Enabled:%d\n", driver->drrs_enabled);
558 	/*
559 	 * If DRRS is not supported, drrs_type has to be set to 0.
560 	 * This is because, VBT is configured in such a way that
561 	 * static DRRS is 0 and DRRS not supported is represented by
562 	 * driver->drrs_enabled=false
563 	 */
564 	if (!driver->drrs_enabled)
565 		dev_priv->vbt.drrs_type = DRRS_NOT_SUPPORTED;
566 }
567 
568 static void
569 parse_edp(struct drm_i915_private *dev_priv, struct bdb_header *bdb)
570 {
571 	struct bdb_edp *edp;
572 	struct edp_power_seq *edp_pps;
573 	struct edp_link_params *edp_link_params;
574 
575 	edp = find_section(bdb, BDB_EDP);
576 	if (!edp) {
577 		if (dev_priv->vbt.edp_support)
578 			DRM_DEBUG_KMS("No eDP BDB found but eDP panel supported.\n");
579 		return;
580 	}
581 
582 	switch ((edp->color_depth >> (panel_type * 2)) & 3) {
583 	case EDP_18BPP:
584 		dev_priv->vbt.edp_bpp = 18;
585 		break;
586 	case EDP_24BPP:
587 		dev_priv->vbt.edp_bpp = 24;
588 		break;
589 	case EDP_30BPP:
590 		dev_priv->vbt.edp_bpp = 30;
591 		break;
592 	}
593 
594 	/* Get the eDP sequencing and link info */
595 	edp_pps = &edp->power_seqs[panel_type];
596 	edp_link_params = &edp->link_params[panel_type];
597 
598 	dev_priv->vbt.edp_pps = *edp_pps;
599 
600 	switch (edp_link_params->rate) {
601 	case EDP_RATE_1_62:
602 		dev_priv->vbt.edp_rate = DP_LINK_BW_1_62;
603 		break;
604 	case EDP_RATE_2_7:
605 		dev_priv->vbt.edp_rate = DP_LINK_BW_2_7;
606 		break;
607 	default:
608 		DRM_DEBUG_KMS("VBT has unknown eDP link rate value %u\n",
609 			      edp_link_params->rate);
610 		break;
611 	}
612 
613 	switch (edp_link_params->lanes) {
614 	case EDP_LANE_1:
615 		dev_priv->vbt.edp_lanes = 1;
616 		break;
617 	case EDP_LANE_2:
618 		dev_priv->vbt.edp_lanes = 2;
619 		break;
620 	case EDP_LANE_4:
621 		dev_priv->vbt.edp_lanes = 4;
622 		break;
623 	default:
624 		DRM_DEBUG_KMS("VBT has unknown eDP lane count value %u\n",
625 			      edp_link_params->lanes);
626 		break;
627 	}
628 
629 	switch (edp_link_params->preemphasis) {
630 	case EDP_PREEMPHASIS_NONE:
631 		dev_priv->vbt.edp_preemphasis = DP_TRAIN_PRE_EMPH_LEVEL_0;
632 		break;
633 	case EDP_PREEMPHASIS_3_5dB:
634 		dev_priv->vbt.edp_preemphasis = DP_TRAIN_PRE_EMPH_LEVEL_1;
635 		break;
636 	case EDP_PREEMPHASIS_6dB:
637 		dev_priv->vbt.edp_preemphasis = DP_TRAIN_PRE_EMPH_LEVEL_2;
638 		break;
639 	case EDP_PREEMPHASIS_9_5dB:
640 		dev_priv->vbt.edp_preemphasis = DP_TRAIN_PRE_EMPH_LEVEL_3;
641 		break;
642 	default:
643 		DRM_DEBUG_KMS("VBT has unknown eDP pre-emphasis value %u\n",
644 			      edp_link_params->preemphasis);
645 		break;
646 	}
647 
648 	switch (edp_link_params->vswing) {
649 	case EDP_VSWING_0_4V:
650 		dev_priv->vbt.edp_vswing = DP_TRAIN_VOLTAGE_SWING_LEVEL_0;
651 		break;
652 	case EDP_VSWING_0_6V:
653 		dev_priv->vbt.edp_vswing = DP_TRAIN_VOLTAGE_SWING_LEVEL_1;
654 		break;
655 	case EDP_VSWING_0_8V:
656 		dev_priv->vbt.edp_vswing = DP_TRAIN_VOLTAGE_SWING_LEVEL_2;
657 		break;
658 	case EDP_VSWING_1_2V:
659 		dev_priv->vbt.edp_vswing = DP_TRAIN_VOLTAGE_SWING_LEVEL_3;
660 		break;
661 	default:
662 		DRM_DEBUG_KMS("VBT has unknown eDP voltage swing value %u\n",
663 			      edp_link_params->vswing);
664 		break;
665 	}
666 
667 	if (bdb->version >= 173) {
668 		uint8_t vswing;
669 
670 		vswing = (edp->edp_vswing_preemph >> (panel_type * 4)) & 0xF;
671 		dev_priv->vbt.edp_low_vswing = vswing == 0;
672 	}
673 }
674 
675 static void
676 parse_psr(struct drm_i915_private *dev_priv, struct bdb_header *bdb)
677 {
678 	struct bdb_psr *psr;
679 	struct psr_table *psr_table;
680 
681 	psr = find_section(bdb, BDB_PSR);
682 	if (!psr) {
683 		DRM_DEBUG_KMS("No PSR BDB found.\n");
684 		return;
685 	}
686 
687 	psr_table = &psr->psr_table[panel_type];
688 
689 	dev_priv->vbt.psr.full_link = psr_table->full_link;
690 	dev_priv->vbt.psr.require_aux_wakeup = psr_table->require_aux_to_wakeup;
691 
692 	/* Allowed VBT values goes from 0 to 15 */
693 	dev_priv->vbt.psr.idle_frames = psr_table->idle_frames < 0 ? 0 :
694 		psr_table->idle_frames > 15 ? 15 : psr_table->idle_frames;
695 
696 	switch (psr_table->lines_to_wait) {
697 	case 0:
698 		dev_priv->vbt.psr.lines_to_wait = PSR_0_LINES_TO_WAIT;
699 		break;
700 	case 1:
701 		dev_priv->vbt.psr.lines_to_wait = PSR_1_LINE_TO_WAIT;
702 		break;
703 	case 2:
704 		dev_priv->vbt.psr.lines_to_wait = PSR_4_LINES_TO_WAIT;
705 		break;
706 	case 3:
707 		dev_priv->vbt.psr.lines_to_wait = PSR_8_LINES_TO_WAIT;
708 		break;
709 	default:
710 		DRM_DEBUG_KMS("VBT has unknown PSR lines to wait %u\n",
711 			      psr_table->lines_to_wait);
712 		break;
713 	}
714 
715 	dev_priv->vbt.psr.tp1_wakeup_time = psr_table->tp1_wakeup_time;
716 	dev_priv->vbt.psr.tp2_tp3_wakeup_time = psr_table->tp2_tp3_wakeup_time;
717 }
718 
719 static u8 *goto_next_sequence(u8 *data, int *size)
720 {
721 	u16 len;
722 	int tmp = *size;
723 
724 	if (--tmp < 0)
725 		return NULL;
726 
727 	/* goto first element */
728 	data++;
729 	while (1) {
730 		switch (*data) {
731 		case MIPI_SEQ_ELEM_SEND_PKT:
732 			/*
733 			 * skip by this element payload size
734 			 * skip elem id, command flag and data type
735 			 */
736 			tmp -= 5;
737 			if (tmp < 0)
738 				return NULL;
739 
740 			data += 3;
741 			len = *((u16 *)data);
742 
743 			tmp -= len;
744 			if (tmp < 0)
745 				return NULL;
746 
747 			/* skip by len */
748 			data = data + 2 + len;
749 			break;
750 		case MIPI_SEQ_ELEM_DELAY:
751 			/* skip by elem id, and delay is 4 bytes */
752 			tmp -= 5;
753 			if (tmp < 0)
754 				return NULL;
755 
756 			data += 5;
757 			break;
758 		case MIPI_SEQ_ELEM_GPIO:
759 			tmp -= 3;
760 			if (tmp < 0)
761 				return NULL;
762 
763 			data += 3;
764 			break;
765 		default:
766 			DRM_ERROR("Unknown element\n");
767 			return NULL;
768 		}
769 
770 		/* end of sequence ? */
771 		if (*data == 0)
772 			break;
773 	}
774 
775 	/* goto next sequence or end of block byte */
776 	if (--tmp < 0)
777 		return NULL;
778 
779 	data++;
780 
781 	/* update amount of data left for the sequence block to be parsed */
782 	*size = tmp;
783 	return data;
784 }
785 
786 static void
787 parse_mipi(struct drm_i915_private *dev_priv, struct bdb_header *bdb)
788 {
789 	struct bdb_mipi_config *start;
790 	struct bdb_mipi_sequence *sequence;
791 	struct mipi_config *config;
792 	struct mipi_pps_data *pps;
793 	u8 *data, *seq_data;
794 	int i, panel_id, seq_size;
795 	u16 block_size;
796 
797 	/* parse MIPI blocks only if LFP type is MIPI */
798 	if (!dev_priv->vbt.has_mipi)
799 		return;
800 
801 	/* Initialize this to undefined indicating no generic MIPI support */
802 	dev_priv->vbt.dsi.panel_id = MIPI_DSI_UNDEFINED_PANEL_ID;
803 
804 	/* Block #40 is already parsed and panel_fixed_mode is
805 	 * stored in dev_priv->lfp_lvds_vbt_mode
806 	 * resuse this when needed
807 	 */
808 
809 	/* Parse #52 for panel index used from panel_type already
810 	 * parsed
811 	 */
812 	start = find_section(bdb, BDB_MIPI_CONFIG);
813 	if (!start) {
814 		DRM_DEBUG_KMS("No MIPI config BDB found");
815 		return;
816 	}
817 
818 	DRM_DEBUG_DRIVER("Found MIPI Config block, panel index = %d\n",
819 								panel_type);
820 
821 	/*
822 	 * get hold of the correct configuration block and pps data as per
823 	 * the panel_type as index
824 	 */
825 	config = &start->config[panel_type];
826 	pps = &start->pps[panel_type];
827 
828 	/* store as of now full data. Trim when we realise all is not needed */
829 	dev_priv->vbt.dsi.config = kmemdup(config, sizeof(struct mipi_config), GFP_KERNEL);
830 	if (!dev_priv->vbt.dsi.config)
831 		return;
832 
833 	dev_priv->vbt.dsi.pps = kmemdup(pps, sizeof(struct mipi_pps_data), GFP_KERNEL);
834 	if (!dev_priv->vbt.dsi.pps) {
835 		kfree(dev_priv->vbt.dsi.config);
836 		return;
837 	}
838 
839 	/* We have mandatory mipi config blocks. Initialize as generic panel */
840 	dev_priv->vbt.dsi.panel_id = MIPI_DSI_GENERIC_PANEL_ID;
841 
842 	/* Check if we have sequence block as well */
843 	sequence = find_section(bdb, BDB_MIPI_SEQUENCE);
844 	if (!sequence) {
845 		DRM_DEBUG_KMS("No MIPI Sequence found, parsing complete\n");
846 		return;
847 	}
848 
849 	DRM_DEBUG_DRIVER("Found MIPI sequence block\n");
850 
851 	block_size = get_blocksize(sequence);
852 
853 	/*
854 	 * parse the sequence block for individual sequences
855 	 */
856 	dev_priv->vbt.dsi.seq_version = sequence->version;
857 
858 	seq_data = &sequence->data[0];
859 
860 	/*
861 	 * sequence block is variable length and hence we need to parse and
862 	 * get the sequence data for specific panel id
863 	 */
864 	for (i = 0; i < MAX_MIPI_CONFIGURATIONS; i++) {
865 		panel_id = *seq_data;
866 		seq_size = *((u16 *) (seq_data + 1));
867 		if (panel_id == panel_type)
868 			break;
869 
870 		/* skip the sequence including seq header of 3 bytes */
871 		seq_data = seq_data + 3 + seq_size;
872 		if ((seq_data - &sequence->data[0]) > block_size) {
873 			DRM_ERROR("Sequence start is beyond sequence block size, corrupted sequence block\n");
874 			return;
875 		}
876 	}
877 
878 	if (i == MAX_MIPI_CONFIGURATIONS) {
879 		DRM_ERROR("Sequence block detected but no valid configuration\n");
880 		return;
881 	}
882 
883 	/* check if found sequence is completely within the sequence block
884 	 * just being paranoid */
885 	if (seq_size > block_size) {
886 		DRM_ERROR("Corrupted sequence/size, bailing out\n");
887 		return;
888 	}
889 
890 	/* skip the panel id(1 byte) and seq size(2 bytes) */
891 	dev_priv->vbt.dsi.data = kmemdup(seq_data + 3, seq_size, GFP_KERNEL);
892 	if (!dev_priv->vbt.dsi.data)
893 		return;
894 
895 	/*
896 	 * loop into the sequence data and split into multiple sequneces
897 	 * There are only 5 types of sequences as of now
898 	 */
899 	data = dev_priv->vbt.dsi.data;
900 	dev_priv->vbt.dsi.size = seq_size;
901 
902 	/* two consecutive 0x00 indicate end of all sequences */
903 	while (1) {
904 		int seq_id = *data;
905 		if (MIPI_SEQ_MAX > seq_id && seq_id > MIPI_SEQ_UNDEFINED) {
906 			dev_priv->vbt.dsi.sequence[seq_id] = data;
907 			DRM_DEBUG_DRIVER("Found mipi sequence - %d\n", seq_id);
908 		} else {
909 			DRM_ERROR("undefined sequence\n");
910 			goto err;
911 		}
912 
913 		/* partial parsing to skip elements */
914 		data = goto_next_sequence(data, &seq_size);
915 
916 		if (data == NULL) {
917 			DRM_ERROR("Sequence elements going beyond block itself. Sequence block parsing failed\n");
918 			goto err;
919 		}
920 
921 		if (*data == 0)
922 			break; /* end of sequence reached */
923 	}
924 
925 	DRM_DEBUG_DRIVER("MIPI related vbt parsing complete\n");
926 	return;
927 err:
928 	kfree(dev_priv->vbt.dsi.data);
929 	dev_priv->vbt.dsi.data = NULL;
930 
931 	/* error during parsing so set all pointers to null
932 	 * because of partial parsing */
933 	memset(dev_priv->vbt.dsi.sequence, 0, sizeof(dev_priv->vbt.dsi.sequence));
934 }
935 
936 static void parse_ddi_port(struct drm_i915_private *dev_priv, enum port port,
937 			   struct bdb_header *bdb)
938 {
939 	union child_device_config *it, *child = NULL;
940 	struct ddi_vbt_port_info *info = &dev_priv->vbt.ddi_port_info[port];
941 	uint8_t hdmi_level_shift;
942 	int i, j;
943 	bool is_dvi, is_hdmi, is_dp, is_edp, is_crt;
944 	uint8_t aux_channel;
945 	/* Each DDI port can have more than one value on the "DVO Port" field,
946 	 * so look for all the possible values for each port and abort if more
947 	 * than one is found. */
948 	int dvo_ports[][2] = {
949 		{DVO_PORT_HDMIA, DVO_PORT_DPA},
950 		{DVO_PORT_HDMIB, DVO_PORT_DPB},
951 		{DVO_PORT_HDMIC, DVO_PORT_DPC},
952 		{DVO_PORT_HDMID, DVO_PORT_DPD},
953 		{DVO_PORT_CRT, -1 /* Port E can only be DVO_PORT_CRT */ },
954 	};
955 
956 	/* Find the child device to use, abort if more than one found. */
957 	for (i = 0; i < dev_priv->vbt.child_dev_num; i++) {
958 		it = dev_priv->vbt.child_dev + i;
959 
960 		for (j = 0; j < 2; j++) {
961 			if (dvo_ports[port][j] == -1)
962 				break;
963 
964 			if (it->common.dvo_port == dvo_ports[port][j]) {
965 				if (child) {
966 					DRM_DEBUG_KMS("More than one child device for port %c in VBT.\n",
967 						      port_name(port));
968 					return;
969 				}
970 				child = it;
971 			}
972 		}
973 	}
974 	if (!child)
975 		return;
976 
977 	aux_channel = child->raw[25];
978 
979 	is_dvi = child->common.device_type & DEVICE_TYPE_TMDS_DVI_SIGNALING;
980 	is_dp = child->common.device_type & DEVICE_TYPE_DISPLAYPORT_OUTPUT;
981 	is_crt = child->common.device_type & DEVICE_TYPE_ANALOG_OUTPUT;
982 	is_hdmi = is_dvi && (child->common.device_type & DEVICE_TYPE_NOT_HDMI_OUTPUT) == 0;
983 	is_edp = is_dp && (child->common.device_type & DEVICE_TYPE_INTERNAL_CONNECTOR);
984 
985 	info->supports_dvi = is_dvi;
986 	info->supports_hdmi = is_hdmi;
987 	info->supports_dp = is_dp;
988 
989 	DRM_DEBUG_KMS("Port %c VBT info: DP:%d HDMI:%d DVI:%d EDP:%d CRT:%d\n",
990 		      port_name(port), is_dp, is_hdmi, is_dvi, is_edp, is_crt);
991 
992 	if (is_edp && is_dvi)
993 		DRM_DEBUG_KMS("Internal DP port %c is TMDS compatible\n",
994 			      port_name(port));
995 	if (is_crt && port != PORT_E)
996 		DRM_DEBUG_KMS("Port %c is analog\n", port_name(port));
997 	if (is_crt && (is_dvi || is_dp))
998 		DRM_DEBUG_KMS("Analog port %c is also DP or TMDS compatible\n",
999 			      port_name(port));
1000 	if (is_dvi && (port == PORT_A || port == PORT_E))
1001 		DRM_DEBUG_KMS("Port %c is TMDS compatible\n", port_name(port));
1002 	if (!is_dvi && !is_dp && !is_crt)
1003 		DRM_DEBUG_KMS("Port %c is not DP/TMDS/CRT compatible\n",
1004 			      port_name(port));
1005 	if (is_edp && (port == PORT_B || port == PORT_C || port == PORT_E))
1006 		DRM_DEBUG_KMS("Port %c is internal DP\n", port_name(port));
1007 
1008 	if (is_dvi) {
1009 		if (child->common.ddc_pin == 0x05 && port != PORT_B)
1010 			DRM_DEBUG_KMS("Unexpected DDC pin for port B\n");
1011 		if (child->common.ddc_pin == 0x04 && port != PORT_C)
1012 			DRM_DEBUG_KMS("Unexpected DDC pin for port C\n");
1013 		if (child->common.ddc_pin == 0x06 && port != PORT_D)
1014 			DRM_DEBUG_KMS("Unexpected DDC pin for port D\n");
1015 	}
1016 
1017 	if (is_dp) {
1018 		if (aux_channel == 0x40 && port != PORT_A)
1019 			DRM_DEBUG_KMS("Unexpected AUX channel for port A\n");
1020 		if (aux_channel == 0x10 && port != PORT_B)
1021 			DRM_DEBUG_KMS("Unexpected AUX channel for port B\n");
1022 		if (aux_channel == 0x20 && port != PORT_C)
1023 			DRM_DEBUG_KMS("Unexpected AUX channel for port C\n");
1024 		if (aux_channel == 0x30 && port != PORT_D)
1025 			DRM_DEBUG_KMS("Unexpected AUX channel for port D\n");
1026 	}
1027 
1028 	if (bdb->version >= 158) {
1029 		/* The VBT HDMI level shift values match the table we have. */
1030 		hdmi_level_shift = child->raw[7] & 0xF;
1031 		DRM_DEBUG_KMS("VBT HDMI level shift for port %c: %d\n",
1032 			      port_name(port),
1033 			      hdmi_level_shift);
1034 		info->hdmi_level_shift = hdmi_level_shift;
1035 	}
1036 }
1037 
1038 static void parse_ddi_ports(struct drm_i915_private *dev_priv,
1039 			    struct bdb_header *bdb)
1040 {
1041 	struct drm_device *dev = dev_priv->dev;
1042 	enum port port;
1043 
1044 	if (!HAS_DDI(dev))
1045 		return;
1046 
1047 	if (!dev_priv->vbt.child_dev_num)
1048 		return;
1049 
1050 	if (bdb->version < 155)
1051 		return;
1052 
1053 	for (port = PORT_A; port < I915_MAX_PORTS; port++)
1054 		parse_ddi_port(dev_priv, port, bdb);
1055 }
1056 
1057 static void
1058 parse_device_mapping(struct drm_i915_private *dev_priv,
1059 		       struct bdb_header *bdb)
1060 {
1061 	struct bdb_general_definitions *p_defs;
1062 	union child_device_config *p_child, *child_dev_ptr;
1063 	int i, child_device_num, count;
1064 	u16	block_size;
1065 
1066 	p_defs = find_section(bdb, BDB_GENERAL_DEFINITIONS);
1067 	if (!p_defs) {
1068 		DRM_DEBUG_KMS("No general definition block is found, no devices defined.\n");
1069 		return;
1070 	}
1071 	/* judge whether the size of child device meets the requirements.
1072 	 * If the child device size obtained from general definition block
1073 	 * is different with sizeof(struct child_device_config), skip the
1074 	 * parsing of sdvo device info
1075 	 */
1076 	if (p_defs->child_dev_size != sizeof(*p_child)) {
1077 		/* different child dev size . Ignore it */
1078 		DRM_DEBUG_KMS("different child size is found. Invalid.\n");
1079 		return;
1080 	}
1081 	/* get the block size of general definitions */
1082 	block_size = get_blocksize(p_defs);
1083 	/* get the number of child device */
1084 	child_device_num = (block_size - sizeof(*p_defs)) /
1085 				sizeof(*p_child);
1086 	count = 0;
1087 	/* get the number of child device that is present */
1088 	for (i = 0; i < child_device_num; i++) {
1089 		p_child = &(p_defs->devices[i]);
1090 		if (!p_child->common.device_type) {
1091 			/* skip the device block if device type is invalid */
1092 			continue;
1093 		}
1094 		count++;
1095 	}
1096 	if (!count) {
1097 		DRM_DEBUG_KMS("no child dev is parsed from VBT\n");
1098 		return;
1099 	}
1100 	dev_priv->vbt.child_dev = kcalloc(count, sizeof(*p_child), GFP_KERNEL);
1101 	if (!dev_priv->vbt.child_dev) {
1102 		DRM_DEBUG_KMS("No memory space for child device\n");
1103 		return;
1104 	}
1105 
1106 	dev_priv->vbt.child_dev_num = count;
1107 	count = 0;
1108 	for (i = 0; i < child_device_num; i++) {
1109 		p_child = &(p_defs->devices[i]);
1110 		if (!p_child->common.device_type) {
1111 			/* skip the device block if device type is invalid */
1112 			continue;
1113 		}
1114 
1115 		if (p_child->common.dvo_port >= DVO_PORT_MIPIA
1116 		    && p_child->common.dvo_port <= DVO_PORT_MIPID
1117 		    &&p_child->common.device_type & DEVICE_TYPE_MIPI_OUTPUT) {
1118 			DRM_DEBUG_KMS("Found MIPI as LFP\n");
1119 			dev_priv->vbt.has_mipi = 1;
1120 			dev_priv->vbt.dsi.port = p_child->common.dvo_port;
1121 		}
1122 
1123 		child_dev_ptr = dev_priv->vbt.child_dev + count;
1124 		count++;
1125 		memcpy((void *)child_dev_ptr, (void *)p_child,
1126 					sizeof(*p_child));
1127 	}
1128 	return;
1129 }
1130 
1131 static void
1132 init_vbt_defaults(struct drm_i915_private *dev_priv)
1133 {
1134 	struct drm_device *dev = dev_priv->dev;
1135 	enum port port;
1136 
1137 	dev_priv->vbt.crt_ddc_pin = GMBUS_PORT_VGADDC;
1138 
1139 	/* Default to having backlight */
1140 	dev_priv->vbt.backlight.present = true;
1141 
1142 	/* LFP panel data */
1143 	dev_priv->vbt.lvds_dither = 1;
1144 	dev_priv->vbt.lvds_vbt = 0;
1145 
1146 	/* SDVO panel data */
1147 	dev_priv->vbt.sdvo_lvds_vbt_mode = NULL;
1148 
1149 	/* general features */
1150 	dev_priv->vbt.int_tv_support = 1;
1151 	dev_priv->vbt.int_crt_support = 1;
1152 
1153 	/* Default to using SSC */
1154 	dev_priv->vbt.lvds_use_ssc = 1;
1155 	/*
1156 	 * Core/SandyBridge/IvyBridge use alternative (120MHz) reference
1157 	 * clock for LVDS.
1158 	 */
1159 	dev_priv->vbt.lvds_ssc_freq = intel_bios_ssc_frequency(dev,
1160 			!HAS_PCH_SPLIT(dev));
1161 	DRM_DEBUG_KMS("Set default to SSC at %d kHz\n", dev_priv->vbt.lvds_ssc_freq);
1162 
1163 	for (port = PORT_A; port < I915_MAX_PORTS; port++) {
1164 		struct ddi_vbt_port_info *info =
1165 			&dev_priv->vbt.ddi_port_info[port];
1166 
1167 		info->hdmi_level_shift = HDMI_LEVEL_SHIFT_UNKNOWN;
1168 
1169 		info->supports_dvi = (port != PORT_A && port != PORT_E);
1170 		info->supports_hdmi = info->supports_dvi;
1171 		info->supports_dp = (port != PORT_E);
1172 	}
1173 }
1174 
1175 static int intel_no_opregion_vbt_callback(const struct dmi_system_id *id)
1176 {
1177 	DRM_DEBUG_KMS("Falling back to manually reading VBT from "
1178 		      "VBIOS ROM for %s\n",
1179 		      id->ident);
1180 	return 1;
1181 }
1182 
1183 static const struct dmi_system_id intel_no_opregion_vbt[] = {
1184 	{
1185 		.callback = intel_no_opregion_vbt_callback,
1186 		.ident = "ThinkCentre A57",
1187 		.matches = {
1188 			DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
1189 			DMI_MATCH(DMI_PRODUCT_NAME, "97027RG"),
1190 		},
1191 	},
1192 	{ }
1193 };
1194 
1195 static struct bdb_header *validate_vbt(char *base, size_t size,
1196 				       struct vbt_header *vbt,
1197 				       const char *source)
1198 {
1199 	size_t offset;
1200 	struct bdb_header *bdb;
1201 
1202 	if (vbt == NULL) {
1203 		DRM_DEBUG_DRIVER("VBT signature missing\n");
1204 		return NULL;
1205 	}
1206 
1207 	offset = (char *)vbt - base;
1208 	if (offset + sizeof(struct vbt_header) > size) {
1209 		DRM_DEBUG_DRIVER("VBT header incomplete\n");
1210 		return NULL;
1211 	}
1212 
1213 	if (memcmp(vbt->signature, "$VBT", 4)) {
1214 		DRM_DEBUG_DRIVER("VBT invalid signature\n");
1215 		return NULL;
1216 	}
1217 
1218 	offset += vbt->bdb_offset;
1219 	if (offset + sizeof(struct bdb_header) > size) {
1220 		DRM_DEBUG_DRIVER("BDB header incomplete\n");
1221 		return NULL;
1222 	}
1223 
1224 	bdb = (struct bdb_header *)(base + offset);
1225 	if (offset + bdb->bdb_size > size) {
1226 		DRM_DEBUG_DRIVER("BDB incomplete\n");
1227 		return NULL;
1228 	}
1229 
1230 	DRM_DEBUG_KMS("Using VBT from %s: %20s\n",
1231 		      source, vbt->signature);
1232 	return bdb;
1233 }
1234 
1235 /**
1236  * intel_parse_bios - find VBT and initialize settings from the BIOS
1237  * @dev: DRM device
1238  *
1239  * Loads the Video BIOS and checks that the VBT exists.  Sets scratch registers
1240  * to appropriate values.
1241  *
1242  * Returns 0 on success, nonzero on failure.
1243  */
1244 int
1245 intel_parse_bios(struct drm_device *dev)
1246 {
1247 	struct drm_i915_private *dev_priv = dev->dev_private;
1248 #if 0
1249 	struct pci_dev *pdev = dev->pdev;
1250 #endif
1251 	struct bdb_header *bdb = NULL;
1252 	u8 __iomem *bios = NULL;
1253 
1254 	if (HAS_PCH_NOP(dev))
1255 		return -ENODEV;
1256 
1257 	init_vbt_defaults(dev_priv);
1258 
1259 	/* XXX Should this validation be moved to intel_opregion.c? */
1260 	if (!dmi_check_system(intel_no_opregion_vbt) && dev_priv->opregion.vbt)
1261 		bdb = validate_vbt((char *)dev_priv->opregion.header, OPREGION_SIZE,
1262 				   (struct vbt_header *)dev_priv->opregion.vbt,
1263 				   "OpRegion");
1264 
1265 	if (bdb == NULL) {
1266 		size_t i, size;
1267 
1268 #if 0
1269 		bios = pci_map_rom(pdev, &size);
1270 		if (!bios)
1271 #endif
1272 			return -1;
1273 
1274 		/* Scour memory looking for the VBT signature */
1275 		for (i = 0; i + 4 < size; i++) {
1276 			if (memcmp(bios + i, "$VBT", 4) == 0) {
1277 				bdb = validate_vbt(bios, size,
1278 						   (struct vbt_header *)(bios + i),
1279 						   "PCI ROM");
1280 				break;
1281 			}
1282 		}
1283 
1284 		if (!bdb) {
1285 #if 0
1286 			pci_unmap_rom(pdev, bios);
1287 #endif
1288 			return -1;
1289 		}
1290 	}
1291 
1292 	/* Grab useful general definitions */
1293 	parse_general_features(dev_priv, bdb);
1294 	parse_general_definitions(dev_priv, bdb);
1295 	parse_lfp_panel_data(dev_priv, bdb);
1296 	parse_lfp_backlight(dev_priv, bdb);
1297 	parse_sdvo_panel_data(dev_priv, bdb);
1298 	parse_sdvo_device_mapping(dev_priv, bdb);
1299 	parse_device_mapping(dev_priv, bdb);
1300 	parse_driver_features(dev_priv, bdb);
1301 	parse_edp(dev_priv, bdb);
1302 	parse_psr(dev_priv, bdb);
1303 	parse_mipi(dev_priv, bdb);
1304 	parse_ddi_ports(dev_priv, bdb);
1305 
1306 #if 0
1307 	if (bios)
1308 		pci_unmap_rom(pdev, bios);
1309 #endif
1310 
1311 	return 0;
1312 }
1313 
1314 /* Ensure that vital registers have been initialised, even if the BIOS
1315  * is absent or just failing to do its job.
1316  */
1317 void intel_setup_bios(struct drm_device *dev)
1318 {
1319 	struct drm_i915_private *dev_priv = dev->dev_private;
1320 
1321 	 /* Set the Panel Power On/Off timings if uninitialized. */
1322 	if (!HAS_PCH_SPLIT(dev) &&
1323 	    I915_READ(PP_ON_DELAYS) == 0 && I915_READ(PP_OFF_DELAYS) == 0) {
1324 		/* Set T2 to 40ms and T5 to 200ms */
1325 		I915_WRITE(PP_ON_DELAYS, 0x019007d0);
1326 
1327 		/* Set T3 to 35ms and Tx to 200ms */
1328 		I915_WRITE(PP_OFF_DELAYS, 0x015e07d0);
1329 	}
1330 }
1331