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/drm_dp_helper.h>
29#include <drm/drmP.h>
30#include <drm/i915_drm.h>
31#include "i915_drv.h"
32#include "intel_bios.h"
33
34#define	SLAVE_ADDR1	0x70
35#define	SLAVE_ADDR2	0x72
36
37static int panel_type;
38
39static void *
40find_section(struct bdb_header *bdb, int section_id)
41{
42	u8 *base = (u8 *)bdb;
43	int index = 0;
44	u32 total, current_size;
45	u8 current_id;
46
47	/* skip to first section */
48	index += bdb->header_size;
49	total = bdb->bdb_size;
50
51	/* walk the sections looking for section_id */
52	while (index + 3 < total) {
53		current_id = *(base + index);
54		index++;
55
56		current_size = *((u16 *)(base + index));
57		index += 2;
58
59		/* The MIPI Sequence Block v3+ has a separate size field. */
60		if (current_id == BDB_MIPI_SEQUENCE && *(base + index) >= 3)
61			current_size = *((const u32 *)(base + index + 1));
62
63		if (index + current_size > total)
64			return NULL;
65
66		if (current_id == section_id)
67			return base + index;
68
69		index += current_size;
70	}
71
72	return NULL;
73}
74
75static u16
76get_blocksize(void *p)
77{
78	u16 *block_ptr, block_size;
79
80	block_ptr = (u16 *)((char *)p - 2);
81	block_size = *block_ptr;
82	return block_size;
83}
84
85static void
86fill_detail_timing_data(struct drm_display_mode *panel_fixed_mode,
87			const struct lvds_dvo_timing *dvo_timing)
88{
89	panel_fixed_mode->hdisplay = (dvo_timing->hactive_hi << 8) |
90		dvo_timing->hactive_lo;
91	panel_fixed_mode->hsync_start = panel_fixed_mode->hdisplay +
92		((dvo_timing->hsync_off_hi << 8) | dvo_timing->hsync_off_lo);
93	panel_fixed_mode->hsync_end = panel_fixed_mode->hsync_start +
94		dvo_timing->hsync_pulse_width;
95	panel_fixed_mode->htotal = panel_fixed_mode->hdisplay +
96		((dvo_timing->hblank_hi << 8) | dvo_timing->hblank_lo);
97
98	panel_fixed_mode->vdisplay = (dvo_timing->vactive_hi << 8) |
99		dvo_timing->vactive_lo;
100	panel_fixed_mode->vsync_start = panel_fixed_mode->vdisplay +
101		dvo_timing->vsync_off;
102	panel_fixed_mode->vsync_end = panel_fixed_mode->vsync_start +
103		dvo_timing->vsync_pulse_width;
104	panel_fixed_mode->vtotal = panel_fixed_mode->vdisplay +
105		((dvo_timing->vblank_hi << 8) | dvo_timing->vblank_lo);
106	panel_fixed_mode->clock = dvo_timing->clock * 10;
107	panel_fixed_mode->type = DRM_MODE_TYPE_PREFERRED;
108
109	if (dvo_timing->hsync_positive)
110		panel_fixed_mode->flags |= DRM_MODE_FLAG_PHSYNC;
111	else
112		panel_fixed_mode->flags |= DRM_MODE_FLAG_NHSYNC;
113
114	if (dvo_timing->vsync_positive)
115		panel_fixed_mode->flags |= DRM_MODE_FLAG_PVSYNC;
116	else
117		panel_fixed_mode->flags |= DRM_MODE_FLAG_NVSYNC;
118
119	/* Some VBTs have bogus h/vtotal values */
120	if (panel_fixed_mode->hsync_end > panel_fixed_mode->htotal)
121		panel_fixed_mode->htotal = panel_fixed_mode->hsync_end + 1;
122	if (panel_fixed_mode->vsync_end > panel_fixed_mode->vtotal)
123		panel_fixed_mode->vtotal = panel_fixed_mode->vsync_end + 1;
124
125	drm_mode_set_name(panel_fixed_mode);
126}
127
128static bool
129lvds_dvo_timing_equal_size(const struct lvds_dvo_timing *a,
130			   const struct lvds_dvo_timing *b)
131{
132	if (a->hactive_hi != b->hactive_hi ||
133	    a->hactive_lo != b->hactive_lo)
134		return false;
135
136	if (a->hsync_off_hi != b->hsync_off_hi ||
137	    a->hsync_off_lo != b->hsync_off_lo)
138		return false;
139
140	if (a->hsync_pulse_width != b->hsync_pulse_width)
141		return false;
142
143	if (a->hblank_hi != b->hblank_hi ||
144	    a->hblank_lo != b->hblank_lo)
145		return false;
146
147	if (a->vactive_hi != b->vactive_hi ||
148	    a->vactive_lo != b->vactive_lo)
149		return false;
150
151	if (a->vsync_off != b->vsync_off)
152		return false;
153
154	if (a->vsync_pulse_width != b->vsync_pulse_width)
155		return false;
156
157	if (a->vblank_hi != b->vblank_hi ||
158	    a->vblank_lo != b->vblank_lo)
159		return false;
160
161	return true;
162}
163
164static const struct lvds_dvo_timing *
165get_lvds_dvo_timing(const struct bdb_lvds_lfp_data *lvds_lfp_data,
166		    const struct bdb_lvds_lfp_data_ptrs *lvds_lfp_data_ptrs,
167		    int index)
168{
169	/*
170	 * the size of fp_timing varies on the different platform.
171	 * So calculate the DVO timing relative offset in LVDS data
172	 * entry to get the DVO timing entry
173	 */
174
175	int lfp_data_size =
176		lvds_lfp_data_ptrs->ptr[1].dvo_timing_offset -
177		lvds_lfp_data_ptrs->ptr[0].dvo_timing_offset;
178	int dvo_timing_offset =
179		lvds_lfp_data_ptrs->ptr[0].dvo_timing_offset -
180		lvds_lfp_data_ptrs->ptr[0].fp_timing_offset;
181	char *entry = (char *)lvds_lfp_data->data + lfp_data_size * index;
182
183	return (struct lvds_dvo_timing *)(entry + dvo_timing_offset);
184}
185
186/* get lvds_fp_timing entry
187 * this function may return NULL if the corresponding entry is invalid
188 */
189static const struct lvds_fp_timing *
190get_lvds_fp_timing(const struct bdb_header *bdb,
191		   const struct bdb_lvds_lfp_data *data,
192		   const struct bdb_lvds_lfp_data_ptrs *ptrs,
193		   int index)
194{
195	size_t data_ofs = (const u8 *)data - (const u8 *)bdb;
196	u16 data_size = ((const u16 *)data)[-1]; /* stored in header */
197	size_t ofs;
198
199	if (index >= ARRAY_SIZE(ptrs->ptr))
200		return NULL;
201	ofs = ptrs->ptr[index].fp_timing_offset;
202	if (ofs < data_ofs ||
203	    ofs + sizeof(struct lvds_fp_timing) > data_ofs + data_size)
204		return NULL;
205	return (const struct lvds_fp_timing *)((const u8 *)bdb + ofs);
206}
207
208/* Try to find integrated panel data */
209static void
210parse_lfp_panel_data(struct drm_i915_private *dev_priv,
211			    struct bdb_header *bdb)
212{
213	const struct bdb_lvds_options *lvds_options;
214	const struct bdb_lvds_lfp_data *lvds_lfp_data;
215	const struct bdb_lvds_lfp_data_ptrs *lvds_lfp_data_ptrs;
216	const struct lvds_dvo_timing *panel_dvo_timing;
217	const struct lvds_fp_timing *fp_timing;
218	struct drm_display_mode *panel_fixed_mode;
219	int i, downclock, drrs_mode;
220
221	lvds_options = find_section(bdb, BDB_LVDS_OPTIONS);
222	if (!lvds_options)
223		return;
224
225	dev_priv->vbt.lvds_dither = lvds_options->pixel_dither;
226	if (lvds_options->panel_type == 0xff)
227		return;
228
229	panel_type = lvds_options->panel_type;
230
231	drrs_mode = (lvds_options->dps_panel_type_bits
232				>> (panel_type * 2)) & MODE_MASK;
233	/*
234	 * VBT has static DRRS = 0 and seamless DRRS = 2.
235	 * The below piece of code is required to adjust vbt.drrs_type
236	 * to match the enum drrs_support_type.
237	 */
238	switch (drrs_mode) {
239	case 0:
240		dev_priv->vbt.drrs_type = STATIC_DRRS_SUPPORT;
241		DRM_DEBUG_KMS("DRRS supported mode is static\n");
242		break;
243	case 2:
244		dev_priv->vbt.drrs_type = SEAMLESS_DRRS_SUPPORT;
245		DRM_DEBUG_KMS("DRRS supported mode is seamless\n");
246		break;
247	default:
248		dev_priv->vbt.drrs_type = DRRS_NOT_SUPPORTED;
249		DRM_DEBUG_KMS("DRRS not supported (VBT input)\n");
250		break;
251	}
252
253	lvds_lfp_data = find_section(bdb, BDB_LVDS_LFP_DATA);
254	if (!lvds_lfp_data)
255		return;
256
257	lvds_lfp_data_ptrs = find_section(bdb, BDB_LVDS_LFP_DATA_PTRS);
258	if (!lvds_lfp_data_ptrs)
259		return;
260
261	dev_priv->vbt.lvds_vbt = 1;
262
263	panel_dvo_timing = get_lvds_dvo_timing(lvds_lfp_data,
264					       lvds_lfp_data_ptrs,
265					       lvds_options->panel_type);
266
267	panel_fixed_mode = kzalloc(sizeof(*panel_fixed_mode), GFP_KERNEL);
268	if (!panel_fixed_mode)
269		return;
270
271	fill_detail_timing_data(panel_fixed_mode, panel_dvo_timing);
272
273	dev_priv->vbt.lfp_lvds_vbt_mode = panel_fixed_mode;
274
275	DRM_DEBUG_KMS("Found panel mode in BIOS VBT tables:\n");
276	drm_mode_debug_printmodeline(panel_fixed_mode);
277
278	/*
279	 * Iterate over the LVDS panel timing info to find the lowest clock
280	 * for the native resolution.
281	 */
282	downclock = panel_dvo_timing->clock;
283	for (i = 0; i < 16; i++) {
284		const struct lvds_dvo_timing *dvo_timing;
285
286		dvo_timing = get_lvds_dvo_timing(lvds_lfp_data,
287						 lvds_lfp_data_ptrs,
288						 i);
289		if (lvds_dvo_timing_equal_size(dvo_timing, panel_dvo_timing) &&
290		    dvo_timing->clock < downclock)
291			downclock = dvo_timing->clock;
292	}
293
294	if (downclock < panel_dvo_timing->clock && i915.lvds_downclock) {
295		dev_priv->lvds_downclock_avail = 1;
296		dev_priv->lvds_downclock = downclock * 10;
297		DRM_DEBUG_KMS("LVDS downclock is found in VBT. "
298			      "Normal Clock %dKHz, downclock %dKHz\n",
299			      panel_fixed_mode->clock, 10*downclock);
300	}
301
302	fp_timing = get_lvds_fp_timing(bdb, lvds_lfp_data,
303				       lvds_lfp_data_ptrs,
304				       lvds_options->panel_type);
305	if (fp_timing) {
306		/* check the resolution, just to be sure */
307		if (fp_timing->x_res == panel_fixed_mode->hdisplay &&
308		    fp_timing->y_res == panel_fixed_mode->vdisplay) {
309			dev_priv->vbt.bios_lvds_val = fp_timing->lvds_reg_val;
310			DRM_DEBUG_KMS("VBT initial LVDS value %x\n",
311				      dev_priv->vbt.bios_lvds_val);
312		}
313	}
314}
315
316static void
317parse_lfp_backlight(struct drm_i915_private *dev_priv, struct bdb_header *bdb)
318{
319	const struct bdb_lfp_backlight_data *backlight_data;
320	const struct bdb_lfp_backlight_data_entry *entry;
321
322	backlight_data = find_section(bdb, BDB_LVDS_BACKLIGHT);
323	if (!backlight_data)
324		return;
325
326	if (backlight_data->entry_size != sizeof(backlight_data->data[0])) {
327		DRM_DEBUG_KMS("Unsupported backlight data entry size %u\n",
328			      backlight_data->entry_size);
329		return;
330	}
331
332	entry = &backlight_data->data[panel_type];
333
334	dev_priv->vbt.backlight.present = entry->type == BDB_BACKLIGHT_TYPE_PWM;
335	if (!dev_priv->vbt.backlight.present) {
336		DRM_DEBUG_KMS("PWM backlight not present in VBT (type %u)\n",
337			      entry->type);
338		return;
339	}
340
341	dev_priv->vbt.backlight.pwm_freq_hz = entry->pwm_freq_hz;
342	dev_priv->vbt.backlight.active_low_pwm = entry->active_low_pwm;
343	dev_priv->vbt.backlight.min_brightness = entry->min_brightness;
344	DRM_DEBUG_KMS("VBT backlight PWM modulation frequency %u Hz, "
345		      "active %s, min brightness %u, level %u\n",
346		      dev_priv->vbt.backlight.pwm_freq_hz,
347		      dev_priv->vbt.backlight.active_low_pwm ? "low" : "high",
348		      dev_priv->vbt.backlight.min_brightness,
349		      backlight_data->level[panel_type]);
350}
351
352/* Try to find sdvo panel data */
353static void
354parse_sdvo_panel_data(struct drm_i915_private *dev_priv,
355		      struct bdb_header *bdb)
356{
357	struct lvds_dvo_timing *dvo_timing;
358	struct drm_display_mode *panel_fixed_mode;
359	int index;
360
361	index = i915.vbt_sdvo_panel_type;
362	if (index == -2) {
363		DRM_DEBUG_KMS("Ignore SDVO panel mode from BIOS VBT tables.\n");
364		return;
365	}
366
367	if (index == -1) {
368		struct bdb_sdvo_lvds_options *sdvo_lvds_options;
369
370		sdvo_lvds_options = find_section(bdb, BDB_SDVO_LVDS_OPTIONS);
371		if (!sdvo_lvds_options)
372			return;
373
374		index = sdvo_lvds_options->panel_type;
375	}
376
377	dvo_timing = find_section(bdb, BDB_SDVO_PANEL_DTDS);
378	if (!dvo_timing)
379		return;
380
381	panel_fixed_mode = kzalloc(sizeof(*panel_fixed_mode), GFP_KERNEL);
382	if (!panel_fixed_mode)
383		return;
384
385	fill_detail_timing_data(panel_fixed_mode, dvo_timing + index);
386
387	dev_priv->vbt.sdvo_lvds_vbt_mode = panel_fixed_mode;
388
389	DRM_DEBUG_KMS("Found SDVO panel mode in BIOS VBT tables:\n");
390	drm_mode_debug_printmodeline(panel_fixed_mode);
391}
392
393static int intel_bios_ssc_frequency(struct drm_device *dev,
394				    bool alternate)
395{
396	switch (INTEL_INFO(dev)->gen) {
397	case 2:
398		return alternate ? 66667 : 48000;
399	case 3:
400	case 4:
401		return alternate ? 100000 : 96000;
402	default:
403		return alternate ? 100000 : 120000;
404	}
405}
406
407static void
408parse_general_features(struct drm_i915_private *dev_priv,
409		       struct bdb_header *bdb)
410{
411	struct drm_device *dev = dev_priv->dev;
412	struct bdb_general_features *general;
413
414	general = find_section(bdb, BDB_GENERAL_FEATURES);
415	if (general) {
416		dev_priv->vbt.int_tv_support = general->int_tv_support;
417		dev_priv->vbt.int_crt_support = general->int_crt_support;
418		dev_priv->vbt.lvds_use_ssc = general->enable_ssc;
419		dev_priv->vbt.lvds_ssc_freq =
420			intel_bios_ssc_frequency(dev, general->ssc_freq);
421		dev_priv->vbt.display_clock_mode = general->display_clock_mode;
422		dev_priv->vbt.fdi_rx_polarity_inverted = general->fdi_rx_polarity_inverted;
423		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",
424			      dev_priv->vbt.int_tv_support,
425			      dev_priv->vbt.int_crt_support,
426			      dev_priv->vbt.lvds_use_ssc,
427			      dev_priv->vbt.lvds_ssc_freq,
428			      dev_priv->vbt.display_clock_mode,
429			      dev_priv->vbt.fdi_rx_polarity_inverted);
430	}
431}
432
433static void
434parse_general_definitions(struct drm_i915_private *dev_priv,
435			  struct bdb_header *bdb)
436{
437	struct bdb_general_definitions *general;
438
439	general = find_section(bdb, BDB_GENERAL_DEFINITIONS);
440	if (general) {
441		u16 block_size = get_blocksize(general);
442		if (block_size >= sizeof(*general)) {
443			int bus_pin = general->crt_ddc_gmbus_pin;
444			DRM_DEBUG_KMS("crt_ddc_bus_pin: %d\n", bus_pin);
445			if (intel_gmbus_is_port_valid(bus_pin))
446				dev_priv->vbt.crt_ddc_pin = bus_pin;
447		} else {
448			DRM_DEBUG_KMS("BDB_GD too small (%d). Invalid.\n",
449				      block_size);
450		}
451	}
452}
453
454static void
455parse_sdvo_device_mapping(struct drm_i915_private *dev_priv,
456			  struct bdb_header *bdb)
457{
458	struct sdvo_device_mapping *p_mapping;
459	struct bdb_general_definitions *p_defs;
460	union child_device_config *p_child;
461	int i, child_device_num, count;
462	u16	block_size;
463
464	p_defs = find_section(bdb, BDB_GENERAL_DEFINITIONS);
465	if (!p_defs) {
466		DRM_DEBUG_KMS("No general definition block is found, unable to construct sdvo mapping.\n");
467		return;
468	}
469	/* judge whether the size of child device meets the requirements.
470	 * If the child device size obtained from general definition block
471	 * is different with sizeof(struct child_device_config), skip the
472	 * parsing of sdvo device info
473	 */
474	if (p_defs->child_dev_size != sizeof(*p_child)) {
475		/* different child dev size . Ignore it */
476		DRM_DEBUG_KMS("different child size is found. Invalid.\n");
477		return;
478	}
479	/* get the block size of general definitions */
480	block_size = get_blocksize(p_defs);
481	/* get the number of child device */
482	child_device_num = (block_size - sizeof(*p_defs)) /
483				sizeof(*p_child);
484	count = 0;
485	for (i = 0; i < child_device_num; i++) {
486		p_child = &(p_defs->devices[i]);
487		if (!p_child->old.device_type) {
488			/* skip the device block if device type is invalid */
489			continue;
490		}
491		if (p_child->old.slave_addr != SLAVE_ADDR1 &&
492			p_child->old.slave_addr != SLAVE_ADDR2) {
493			/*
494			 * If the slave address is neither 0x70 nor 0x72,
495			 * it is not a SDVO device. Skip it.
496			 */
497			continue;
498		}
499		if (p_child->old.dvo_port != DEVICE_PORT_DVOB &&
500			p_child->old.dvo_port != DEVICE_PORT_DVOC) {
501			/* skip the incorrect SDVO port */
502			DRM_DEBUG_KMS("Incorrect SDVO port. Skip it\n");
503			continue;
504		}
505		DRM_DEBUG_KMS("the SDVO device with slave addr %2x is found on"
506				" %s port\n",
507				p_child->old.slave_addr,
508				(p_child->old.dvo_port == DEVICE_PORT_DVOB) ?
509					"SDVOB" : "SDVOC");
510		p_mapping = &(dev_priv->sdvo_mappings[p_child->old.dvo_port - 1]);
511		if (!p_mapping->initialized) {
512			p_mapping->dvo_port = p_child->old.dvo_port;
513			p_mapping->slave_addr = p_child->old.slave_addr;
514			p_mapping->dvo_wiring = p_child->old.dvo_wiring;
515			p_mapping->ddc_pin = p_child->old.ddc_pin;
516			p_mapping->i2c_pin = p_child->old.i2c_pin;
517			p_mapping->initialized = 1;
518			DRM_DEBUG_KMS("SDVO device: dvo=%x, addr=%x, wiring=%d, ddc_pin=%d, i2c_pin=%d\n",
519				      p_mapping->dvo_port,
520				      p_mapping->slave_addr,
521				      p_mapping->dvo_wiring,
522				      p_mapping->ddc_pin,
523				      p_mapping->i2c_pin);
524		} else {
525			DRM_DEBUG_KMS("Maybe one SDVO port is shared by "
526					 "two SDVO device.\n");
527		}
528		if (p_child->old.slave2_addr) {
529			/* Maybe this is a SDVO device with multiple inputs */
530			/* And the mapping info is not added */
531			DRM_DEBUG_KMS("there exists the slave2_addr. Maybe this"
532				" is a SDVO device with multiple inputs.\n");
533		}
534		count++;
535	}
536
537	if (!count) {
538		/* No SDVO device info is found */
539		DRM_DEBUG_KMS("No SDVO device info is found in VBT\n");
540	}
541	return;
542}
543
544static void
545parse_driver_features(struct drm_i915_private *dev_priv,
546		       struct bdb_header *bdb)
547{
548	struct bdb_driver_features *driver;
549
550	driver = find_section(bdb, BDB_DRIVER_FEATURES);
551	if (!driver)
552		return;
553
554	if (driver->lvds_config == BDB_DRIVER_FEATURE_EDP)
555		dev_priv->vbt.edp_support = 1;
556
557	if (driver->dual_frequency)
558		dev_priv->render_reclock_avail = true;
559
560	DRM_DEBUG_KMS("DRRS State Enabled:%d\n", driver->drrs_enabled);
561	/*
562	 * If DRRS is not supported, drrs_type has to be set to 0.
563	 * This is because, VBT is configured in such a way that
564	 * static DRRS is 0 and DRRS not supported is represented by
565	 * driver->drrs_enabled=false
566	 */
567	if (!driver->drrs_enabled)
568		dev_priv->vbt.drrs_type = DRRS_NOT_SUPPORTED;
569}
570
571static void
572parse_edp(struct drm_i915_private *dev_priv, struct bdb_header *bdb)
573{
574	struct bdb_edp *edp;
575	struct edp_power_seq *edp_pps;
576	struct edp_link_params *edp_link_params;
577
578	edp = find_section(bdb, BDB_EDP);
579	if (!edp) {
580		if (dev_priv->vbt.edp_support)
581			DRM_DEBUG_KMS("No eDP BDB found but eDP panel supported.\n");
582		return;
583	}
584
585	switch ((edp->color_depth >> (panel_type * 2)) & 3) {
586	case EDP_18BPP:
587		dev_priv->vbt.edp_bpp = 18;
588		break;
589	case EDP_24BPP:
590		dev_priv->vbt.edp_bpp = 24;
591		break;
592	case EDP_30BPP:
593		dev_priv->vbt.edp_bpp = 30;
594		break;
595	}
596
597	/* Get the eDP sequencing and link info */
598	edp_pps = &edp->power_seqs[panel_type];
599	edp_link_params = &edp->link_params[panel_type];
600
601	dev_priv->vbt.edp_pps = *edp_pps;
602
603	switch (edp_link_params->rate) {
604	case EDP_RATE_1_62:
605		dev_priv->vbt.edp_rate = DP_LINK_BW_1_62;
606		break;
607	case EDP_RATE_2_7:
608		dev_priv->vbt.edp_rate = DP_LINK_BW_2_7;
609		break;
610	default:
611		DRM_DEBUG_KMS("VBT has unknown eDP link rate value %u\n",
612			      edp_link_params->rate);
613		break;
614	}
615
616	switch (edp_link_params->lanes) {
617	case EDP_LANE_1:
618		dev_priv->vbt.edp_lanes = 1;
619		break;
620	case EDP_LANE_2:
621		dev_priv->vbt.edp_lanes = 2;
622		break;
623	case EDP_LANE_4:
624		dev_priv->vbt.edp_lanes = 4;
625		break;
626	default:
627		DRM_DEBUG_KMS("VBT has unknown eDP lane count value %u\n",
628			      edp_link_params->lanes);
629		break;
630	}
631
632	switch (edp_link_params->preemphasis) {
633	case EDP_PREEMPHASIS_NONE:
634		dev_priv->vbt.edp_preemphasis = DP_TRAIN_PRE_EMPH_LEVEL_0;
635		break;
636	case EDP_PREEMPHASIS_3_5dB:
637		dev_priv->vbt.edp_preemphasis = DP_TRAIN_PRE_EMPH_LEVEL_1;
638		break;
639	case EDP_PREEMPHASIS_6dB:
640		dev_priv->vbt.edp_preemphasis = DP_TRAIN_PRE_EMPH_LEVEL_2;
641		break;
642	case EDP_PREEMPHASIS_9_5dB:
643		dev_priv->vbt.edp_preemphasis = DP_TRAIN_PRE_EMPH_LEVEL_3;
644		break;
645	default:
646		DRM_DEBUG_KMS("VBT has unknown eDP pre-emphasis value %u\n",
647			      edp_link_params->preemphasis);
648		break;
649	}
650
651	switch (edp_link_params->vswing) {
652	case EDP_VSWING_0_4V:
653		dev_priv->vbt.edp_vswing = DP_TRAIN_VOLTAGE_SWING_LEVEL_0;
654		break;
655	case EDP_VSWING_0_6V:
656		dev_priv->vbt.edp_vswing = DP_TRAIN_VOLTAGE_SWING_LEVEL_1;
657		break;
658	case EDP_VSWING_0_8V:
659		dev_priv->vbt.edp_vswing = DP_TRAIN_VOLTAGE_SWING_LEVEL_2;
660		break;
661	case EDP_VSWING_1_2V:
662		dev_priv->vbt.edp_vswing = DP_TRAIN_VOLTAGE_SWING_LEVEL_3;
663		break;
664	default:
665		DRM_DEBUG_KMS("VBT has unknown eDP voltage swing value %u\n",
666			      edp_link_params->vswing);
667		break;
668	}
669
670	if (bdb->version >= 173) {
671		uint8_t vswing;
672
673		vswing = (edp->edp_vswing_preemph >> (panel_type * 4)) & 0xF;
674		dev_priv->vbt.edp_low_vswing = vswing == 0;
675	}
676}
677
678static void
679parse_psr(struct drm_i915_private *dev_priv, struct bdb_header *bdb)
680{
681	struct bdb_psr *psr;
682	struct psr_table *psr_table;
683
684	psr = find_section(bdb, BDB_PSR);
685	if (!psr) {
686		DRM_DEBUG_KMS("No PSR BDB found.\n");
687		return;
688	}
689
690	psr_table = &psr->psr_table[panel_type];
691
692	dev_priv->vbt.psr.full_link = psr_table->full_link;
693	dev_priv->vbt.psr.require_aux_wakeup = psr_table->require_aux_to_wakeup;
694
695	/* Allowed VBT values goes from 0 to 15 */
696	dev_priv->vbt.psr.idle_frames = psr_table->idle_frames < 0 ? 0 :
697		psr_table->idle_frames > 15 ? 15 : psr_table->idle_frames;
698
699	switch (psr_table->lines_to_wait) {
700	case 0:
701		dev_priv->vbt.psr.lines_to_wait = PSR_0_LINES_TO_WAIT;
702		break;
703	case 1:
704		dev_priv->vbt.psr.lines_to_wait = PSR_1_LINE_TO_WAIT;
705		break;
706	case 2:
707		dev_priv->vbt.psr.lines_to_wait = PSR_4_LINES_TO_WAIT;
708		break;
709	case 3:
710		dev_priv->vbt.psr.lines_to_wait = PSR_8_LINES_TO_WAIT;
711		break;
712	default:
713		DRM_DEBUG_KMS("VBT has unknown PSR lines to wait %u\n",
714			      psr_table->lines_to_wait);
715		break;
716	}
717
718	dev_priv->vbt.psr.tp1_wakeup_time = psr_table->tp1_wakeup_time;
719	dev_priv->vbt.psr.tp2_tp3_wakeup_time = psr_table->tp2_tp3_wakeup_time;
720}
721
722static u8 *goto_next_sequence(u8 *data, int *size)
723{
724	u16 len;
725	int tmp = *size;
726
727	if (--tmp < 0)
728		return NULL;
729
730	/* goto first element */
731	data++;
732	while (1) {
733		switch (*data) {
734		case MIPI_SEQ_ELEM_SEND_PKT:
735			/*
736			 * skip by this element payload size
737			 * skip elem id, command flag and data type
738			 */
739			tmp -= 5;
740			if (tmp < 0)
741				return NULL;
742
743			data += 3;
744			len = *((u16 *)data);
745
746			tmp -= len;
747			if (tmp < 0)
748				return NULL;
749
750			/* skip by len */
751			data = data + 2 + len;
752			break;
753		case MIPI_SEQ_ELEM_DELAY:
754			/* skip by elem id, and delay is 4 bytes */
755			tmp -= 5;
756			if (tmp < 0)
757				return NULL;
758
759			data += 5;
760			break;
761		case MIPI_SEQ_ELEM_GPIO:
762			tmp -= 3;
763			if (tmp < 0)
764				return NULL;
765
766			data += 3;
767			break;
768		default:
769			DRM_ERROR("Unknown element\n");
770			return NULL;
771		}
772
773		/* end of sequence ? */
774		if (*data == 0)
775			break;
776	}
777
778	/* goto next sequence or end of block byte */
779	if (--tmp < 0)
780		return NULL;
781
782	data++;
783
784	/* update amount of data left for the sequence block to be parsed */
785	*size = tmp;
786	return data;
787}
788
789static void
790parse_mipi(struct drm_i915_private *dev_priv, struct bdb_header *bdb)
791{
792	struct bdb_mipi_config *start;
793	struct bdb_mipi_sequence *sequence;
794	struct mipi_config *config;
795	struct mipi_pps_data *pps;
796	u8 *data, *seq_data;
797	int i, panel_id, seq_size;
798	u16 block_size;
799
800	/* parse MIPI blocks only if LFP type is MIPI */
801	if (!dev_priv->vbt.has_mipi)
802		return;
803
804	/* Initialize this to undefined indicating no generic MIPI support */
805	dev_priv->vbt.dsi.panel_id = MIPI_DSI_UNDEFINED_PANEL_ID;
806
807	/* Block #40 is already parsed and panel_fixed_mode is
808	 * stored in dev_priv->lfp_lvds_vbt_mode
809	 * resuse this when needed
810	 */
811
812	/* Parse #52 for panel index used from panel_type already
813	 * parsed
814	 */
815	start = find_section(bdb, BDB_MIPI_CONFIG);
816	if (!start) {
817		DRM_DEBUG_KMS("No MIPI config BDB found");
818		return;
819	}
820
821	DRM_DEBUG_DRIVER("Found MIPI Config block, panel index = %d\n",
822								panel_type);
823
824	/*
825	 * get hold of the correct configuration block and pps data as per
826	 * the panel_type as index
827	 */
828	config = &start->config[panel_type];
829	pps = &start->pps[panel_type];
830
831	/* store as of now full data. Trim when we realise all is not needed */
832	dev_priv->vbt.dsi.config = kmemdup(config, sizeof(struct mipi_config), GFP_KERNEL);
833	if (!dev_priv->vbt.dsi.config)
834		return;
835
836	dev_priv->vbt.dsi.pps = kmemdup(pps, sizeof(struct mipi_pps_data), GFP_KERNEL);
837	if (!dev_priv->vbt.dsi.pps) {
838		kfree(dev_priv->vbt.dsi.config);
839		return;
840	}
841
842	/* We have mandatory mipi config blocks. Initialize as generic panel */
843	dev_priv->vbt.dsi.panel_id = MIPI_DSI_GENERIC_PANEL_ID;
844
845	/* Check if we have sequence block as well */
846	sequence = find_section(bdb, BDB_MIPI_SEQUENCE);
847	if (!sequence) {
848		DRM_DEBUG_KMS("No MIPI Sequence found, parsing complete\n");
849		return;
850	}
851
852	/* Fail gracefully for forward incompatible sequence block. */
853	if (sequence->version >= 3) {
854		DRM_ERROR("Unable to parse MIPI Sequence Block v3+\n");
855		return;
856	}
857
858	DRM_DEBUG_DRIVER("Found MIPI sequence block\n");
859
860	block_size = get_blocksize(sequence);
861
862	/*
863	 * parse the sequence block for individual sequences
864	 */
865	dev_priv->vbt.dsi.seq_version = sequence->version;
866
867	seq_data = &sequence->data[0];
868
869	/*
870	 * sequence block is variable length and hence we need to parse and
871	 * get the sequence data for specific panel id
872	 */
873	for (i = 0; i < MAX_MIPI_CONFIGURATIONS; i++) {
874		panel_id = *seq_data;
875		seq_size = *((u16 *) (seq_data + 1));
876		if (panel_id == panel_type)
877			break;
878
879		/* skip the sequence including seq header of 3 bytes */
880		seq_data = seq_data + 3 + seq_size;
881		if ((seq_data - &sequence->data[0]) > block_size) {
882			DRM_ERROR("Sequence start is beyond sequence block size, corrupted sequence block\n");
883			return;
884		}
885	}
886
887	if (i == MAX_MIPI_CONFIGURATIONS) {
888		DRM_ERROR("Sequence block detected but no valid configuration\n");
889		return;
890	}
891
892	/* check if found sequence is completely within the sequence block
893	 * just being paranoid */
894	if (seq_size > block_size) {
895		DRM_ERROR("Corrupted sequence/size, bailing out\n");
896		return;
897	}
898
899	/* skip the panel id(1 byte) and seq size(2 bytes) */
900	dev_priv->vbt.dsi.data = kmemdup(seq_data + 3, seq_size, GFP_KERNEL);
901	if (!dev_priv->vbt.dsi.data)
902		return;
903
904	/*
905	 * loop into the sequence data and split into multiple sequneces
906	 * There are only 5 types of sequences as of now
907	 */
908	data = dev_priv->vbt.dsi.data;
909	dev_priv->vbt.dsi.size = seq_size;
910
911	/* two consecutive 0x00 indicate end of all sequences */
912	while (1) {
913		int seq_id = *data;
914		if (MIPI_SEQ_MAX > seq_id && seq_id > MIPI_SEQ_UNDEFINED) {
915			dev_priv->vbt.dsi.sequence[seq_id] = data;
916			DRM_DEBUG_DRIVER("Found mipi sequence - %d\n", seq_id);
917		} else {
918			DRM_ERROR("undefined sequence\n");
919			goto err;
920		}
921
922		/* partial parsing to skip elements */
923		data = goto_next_sequence(data, &seq_size);
924
925		if (data == NULL) {
926			DRM_ERROR("Sequence elements going beyond block itself. Sequence block parsing failed\n");
927			goto err;
928		}
929
930		if (*data == 0)
931			break; /* end of sequence reached */
932	}
933
934	DRM_DEBUG_DRIVER("MIPI related vbt parsing complete\n");
935	return;
936err:
937	kfree(dev_priv->vbt.dsi.data);
938	dev_priv->vbt.dsi.data = NULL;
939
940	/* error during parsing so set all pointers to null
941	 * because of partial parsing */
942	memset(dev_priv->vbt.dsi.sequence, 0, sizeof(dev_priv->vbt.dsi.sequence));
943}
944
945static void parse_ddi_port(struct drm_i915_private *dev_priv, enum port port,
946			   struct bdb_header *bdb)
947{
948	union child_device_config *it, *child = NULL;
949	struct ddi_vbt_port_info *info = &dev_priv->vbt.ddi_port_info[port];
950	uint8_t hdmi_level_shift;
951	int i, j;
952	bool is_dvi, is_hdmi, is_dp, is_edp, is_crt;
953	uint8_t aux_channel;
954	/* Each DDI port can have more than one value on the "DVO Port" field,
955	 * so look for all the possible values for each port and abort if more
956	 * than one is found. */
957	int dvo_ports[][2] = {
958		{DVO_PORT_HDMIA, DVO_PORT_DPA},
959		{DVO_PORT_HDMIB, DVO_PORT_DPB},
960		{DVO_PORT_HDMIC, DVO_PORT_DPC},
961		{DVO_PORT_HDMID, DVO_PORT_DPD},
962		{DVO_PORT_CRT, -1 /* Port E can only be DVO_PORT_CRT */ },
963	};
964
965	/* Find the child device to use, abort if more than one found. */
966	for (i = 0; i < dev_priv->vbt.child_dev_num; i++) {
967		it = dev_priv->vbt.child_dev + i;
968
969		for (j = 0; j < 2; j++) {
970			if (dvo_ports[port][j] == -1)
971				break;
972
973			if (it->common.dvo_port == dvo_ports[port][j]) {
974				if (child) {
975					DRM_DEBUG_KMS("More than one child device for port %c in VBT.\n",
976						      port_name(port));
977					return;
978				}
979				child = it;
980			}
981		}
982	}
983	if (!child)
984		return;
985
986	aux_channel = child->raw[25];
987
988	is_dvi = child->common.device_type & DEVICE_TYPE_TMDS_DVI_SIGNALING;
989	is_dp = child->common.device_type & DEVICE_TYPE_DISPLAYPORT_OUTPUT;
990	is_crt = child->common.device_type & DEVICE_TYPE_ANALOG_OUTPUT;
991	is_hdmi = is_dvi && (child->common.device_type & DEVICE_TYPE_NOT_HDMI_OUTPUT) == 0;
992	is_edp = is_dp && (child->common.device_type & DEVICE_TYPE_INTERNAL_CONNECTOR);
993
994	info->supports_dvi = is_dvi;
995	info->supports_hdmi = is_hdmi;
996	info->supports_dp = is_dp;
997
998	DRM_DEBUG_KMS("Port %c VBT info: DP:%d HDMI:%d DVI:%d EDP:%d CRT:%d\n",
999		      port_name(port), is_dp, is_hdmi, is_dvi, is_edp, is_crt);
1000
1001	if (is_edp && is_dvi)
1002		DRM_DEBUG_KMS("Internal DP port %c is TMDS compatible\n",
1003			      port_name(port));
1004	if (is_crt && port != PORT_E)
1005		DRM_DEBUG_KMS("Port %c is analog\n", port_name(port));
1006	if (is_crt && (is_dvi || is_dp))
1007		DRM_DEBUG_KMS("Analog port %c is also DP or TMDS compatible\n",
1008			      port_name(port));
1009	if (is_dvi && (port == PORT_A || port == PORT_E))
1010		DRM_DEBUG_KMS("Port %c is TMDS compatible\n", port_name(port));
1011	if (!is_dvi && !is_dp && !is_crt)
1012		DRM_DEBUG_KMS("Port %c is not DP/TMDS/CRT compatible\n",
1013			      port_name(port));
1014	if (is_edp && (port == PORT_B || port == PORT_C || port == PORT_E))
1015		DRM_DEBUG_KMS("Port %c is internal DP\n", port_name(port));
1016
1017	if (is_dvi) {
1018		if (child->common.ddc_pin == 0x05 && port != PORT_B)
1019			DRM_DEBUG_KMS("Unexpected DDC pin for port B\n");
1020		if (child->common.ddc_pin == 0x04 && port != PORT_C)
1021			DRM_DEBUG_KMS("Unexpected DDC pin for port C\n");
1022		if (child->common.ddc_pin == 0x06 && port != PORT_D)
1023			DRM_DEBUG_KMS("Unexpected DDC pin for port D\n");
1024	}
1025
1026	if (is_dp) {
1027		if (aux_channel == 0x40 && port != PORT_A)
1028			DRM_DEBUG_KMS("Unexpected AUX channel for port A\n");
1029		if (aux_channel == 0x10 && port != PORT_B)
1030			DRM_DEBUG_KMS("Unexpected AUX channel for port B\n");
1031		if (aux_channel == 0x20 && port != PORT_C)
1032			DRM_DEBUG_KMS("Unexpected AUX channel for port C\n");
1033		if (aux_channel == 0x30 && port != PORT_D)
1034			DRM_DEBUG_KMS("Unexpected AUX channel for port D\n");
1035	}
1036
1037	if (bdb->version >= 158) {
1038		/* The VBT HDMI level shift values match the table we have. */
1039		hdmi_level_shift = child->raw[7] & 0xF;
1040		DRM_DEBUG_KMS("VBT HDMI level shift for port %c: %d\n",
1041			      port_name(port),
1042			      hdmi_level_shift);
1043		info->hdmi_level_shift = hdmi_level_shift;
1044	}
1045}
1046
1047static void parse_ddi_ports(struct drm_i915_private *dev_priv,
1048			    struct bdb_header *bdb)
1049{
1050	struct drm_device *dev = dev_priv->dev;
1051	enum port port;
1052
1053	if (!HAS_DDI(dev))
1054		return;
1055
1056	if (!dev_priv->vbt.child_dev_num)
1057		return;
1058
1059	if (bdb->version < 155)
1060		return;
1061
1062	for (port = PORT_A; port < I915_MAX_PORTS; port++)
1063		parse_ddi_port(dev_priv, port, bdb);
1064}
1065
1066static void
1067parse_device_mapping(struct drm_i915_private *dev_priv,
1068		       struct bdb_header *bdb)
1069{
1070	struct bdb_general_definitions *p_defs;
1071	union child_device_config *p_child, *child_dev_ptr;
1072	int i, child_device_num, count;
1073	u16	block_size;
1074
1075	p_defs = find_section(bdb, BDB_GENERAL_DEFINITIONS);
1076	if (!p_defs) {
1077		DRM_DEBUG_KMS("No general definition block is found, no devices defined.\n");
1078		return;
1079	}
1080	/* judge whether the size of child device meets the requirements.
1081	 * If the child device size obtained from general definition block
1082	 * is different with sizeof(struct child_device_config), skip the
1083	 * parsing of sdvo device info
1084	 */
1085	if (p_defs->child_dev_size != sizeof(*p_child)) {
1086		/* different child dev size . Ignore it */
1087		DRM_DEBUG_KMS("different child size is found. Invalid.\n");
1088		return;
1089	}
1090	/* get the block size of general definitions */
1091	block_size = get_blocksize(p_defs);
1092	/* get the number of child device */
1093	child_device_num = (block_size - sizeof(*p_defs)) /
1094				sizeof(*p_child);
1095	count = 0;
1096	/* get the number of child device that is present */
1097	for (i = 0; i < child_device_num; i++) {
1098		p_child = &(p_defs->devices[i]);
1099		if (!p_child->common.device_type) {
1100			/* skip the device block if device type is invalid */
1101			continue;
1102		}
1103		count++;
1104	}
1105	if (!count) {
1106		DRM_DEBUG_KMS("no child dev is parsed from VBT\n");
1107		return;
1108	}
1109	dev_priv->vbt.child_dev = kcalloc(count, sizeof(*p_child), GFP_KERNEL);
1110	if (!dev_priv->vbt.child_dev) {
1111		DRM_DEBUG_KMS("No memory space for child device\n");
1112		return;
1113	}
1114
1115	dev_priv->vbt.child_dev_num = count;
1116	count = 0;
1117	for (i = 0; i < child_device_num; i++) {
1118		p_child = &(p_defs->devices[i]);
1119		if (!p_child->common.device_type) {
1120			/* skip the device block if device type is invalid */
1121			continue;
1122		}
1123
1124		if (p_child->common.dvo_port >= DVO_PORT_MIPIA
1125		    && p_child->common.dvo_port <= DVO_PORT_MIPID
1126		    &&p_child->common.device_type & DEVICE_TYPE_MIPI_OUTPUT) {
1127			DRM_DEBUG_KMS("Found MIPI as LFP\n");
1128			dev_priv->vbt.has_mipi = 1;
1129			dev_priv->vbt.dsi.port = p_child->common.dvo_port;
1130		}
1131
1132		child_dev_ptr = dev_priv->vbt.child_dev + count;
1133		count++;
1134		memcpy((void *)child_dev_ptr, (void *)p_child,
1135					sizeof(*p_child));
1136	}
1137	return;
1138}
1139
1140static void
1141init_vbt_defaults(struct drm_i915_private *dev_priv)
1142{
1143	struct drm_device *dev = dev_priv->dev;
1144	enum port port;
1145
1146	dev_priv->vbt.crt_ddc_pin = GMBUS_PORT_VGADDC;
1147
1148	/* Default to having backlight */
1149	dev_priv->vbt.backlight.present = true;
1150
1151	/* LFP panel data */
1152	dev_priv->vbt.lvds_dither = 1;
1153	dev_priv->vbt.lvds_vbt = 0;
1154
1155	/* SDVO panel data */
1156	dev_priv->vbt.sdvo_lvds_vbt_mode = NULL;
1157
1158	/* general features */
1159	dev_priv->vbt.int_tv_support = 1;
1160	dev_priv->vbt.int_crt_support = 1;
1161
1162	/* Default to using SSC */
1163	dev_priv->vbt.lvds_use_ssc = 1;
1164	/*
1165	 * Core/SandyBridge/IvyBridge use alternative (120MHz) reference
1166	 * clock for LVDS.
1167	 */
1168	dev_priv->vbt.lvds_ssc_freq = intel_bios_ssc_frequency(dev,
1169			!HAS_PCH_SPLIT(dev));
1170	DRM_DEBUG_KMS("Set default to SSC at %d kHz\n", dev_priv->vbt.lvds_ssc_freq);
1171
1172	for (port = PORT_A; port < I915_MAX_PORTS; port++) {
1173		struct ddi_vbt_port_info *info =
1174			&dev_priv->vbt.ddi_port_info[port];
1175
1176		info->hdmi_level_shift = HDMI_LEVEL_SHIFT_UNKNOWN;
1177
1178		info->supports_dvi = (port != PORT_A && port != PORT_E);
1179		info->supports_hdmi = info->supports_dvi;
1180		info->supports_dp = (port != PORT_E);
1181	}
1182}
1183
1184static int intel_no_opregion_vbt_callback(const struct dmi_system_id *id)
1185{
1186	DRM_DEBUG_KMS("Falling back to manually reading VBT from "
1187		      "VBIOS ROM for %s\n",
1188		      id->ident);
1189	return 1;
1190}
1191
1192static const struct dmi_system_id intel_no_opregion_vbt[] = {
1193	{
1194		.callback = intel_no_opregion_vbt_callback,
1195		.ident = "ThinkCentre A57",
1196		.matches = {
1197			DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
1198			DMI_MATCH(DMI_PRODUCT_NAME, "97027RG"),
1199		},
1200	},
1201	{ }
1202};
1203
1204static struct bdb_header *validate_vbt(char *base, size_t size,
1205				       struct vbt_header *vbt,
1206				       const char *source)
1207{
1208	size_t offset;
1209	struct bdb_header *bdb;
1210
1211	if (vbt == NULL) {
1212		DRM_DEBUG_DRIVER("VBT signature missing\n");
1213		return NULL;
1214	}
1215
1216	offset = (char *)vbt - base;
1217	if (offset + sizeof(struct vbt_header) > size) {
1218		DRM_DEBUG_DRIVER("VBT header incomplete\n");
1219		return NULL;
1220	}
1221
1222	if (memcmp(vbt->signature, "$VBT", 4)) {
1223		DRM_DEBUG_DRIVER("VBT invalid signature\n");
1224		return NULL;
1225	}
1226
1227	offset += vbt->bdb_offset;
1228	if (offset + sizeof(struct bdb_header) > size) {
1229		DRM_DEBUG_DRIVER("BDB header incomplete\n");
1230		return NULL;
1231	}
1232
1233	bdb = (struct bdb_header *)(base + offset);
1234	if (offset + bdb->bdb_size > size) {
1235		DRM_DEBUG_DRIVER("BDB incomplete\n");
1236		return NULL;
1237	}
1238
1239	DRM_DEBUG_KMS("Using VBT from %s: %20s\n",
1240		      source, vbt->signature);
1241	return bdb;
1242}
1243
1244/**
1245 * intel_parse_bios - find VBT and initialize settings from the BIOS
1246 * @dev: DRM device
1247 *
1248 * Loads the Video BIOS and checks that the VBT exists.  Sets scratch registers
1249 * to appropriate values.
1250 *
1251 * Returns 0 on success, nonzero on failure.
1252 */
1253int
1254intel_parse_bios(struct drm_device *dev)
1255{
1256	struct drm_i915_private *dev_priv = dev->dev_private;
1257	struct pci_dev *pdev = dev->pdev;
1258	struct bdb_header *bdb = NULL;
1259	u8 __iomem *bios = NULL;
1260
1261	if (HAS_PCH_NOP(dev))
1262		return -ENODEV;
1263
1264	init_vbt_defaults(dev_priv);
1265
1266	/* XXX Should this validation be moved to intel_opregion.c? */
1267	if (!dmi_check_system(intel_no_opregion_vbt) && dev_priv->opregion.vbt)
1268		bdb = validate_vbt((char *)dev_priv->opregion.header, OPREGION_SIZE,
1269				   (struct vbt_header *)dev_priv->opregion.vbt,
1270				   "OpRegion");
1271
1272	if (bdb == NULL) {
1273		size_t i, size;
1274
1275		bios = pci_map_rom(pdev, &size);
1276		if (!bios)
1277			return -1;
1278
1279		/* Scour memory looking for the VBT signature */
1280		for (i = 0; i + 4 < size; i++) {
1281			if (memcmp(bios + i, "$VBT", 4) == 0) {
1282				bdb = validate_vbt(bios, size,
1283						   (struct vbt_header *)(bios + i),
1284						   "PCI ROM");
1285				break;
1286			}
1287		}
1288
1289		if (!bdb) {
1290			pci_unmap_rom(pdev, bios);
1291			return -1;
1292		}
1293	}
1294
1295	/* Grab useful general definitions */
1296	parse_general_features(dev_priv, bdb);
1297	parse_general_definitions(dev_priv, bdb);
1298	parse_lfp_panel_data(dev_priv, bdb);
1299	parse_lfp_backlight(dev_priv, bdb);
1300	parse_sdvo_panel_data(dev_priv, bdb);
1301	parse_sdvo_device_mapping(dev_priv, bdb);
1302	parse_device_mapping(dev_priv, bdb);
1303	parse_driver_features(dev_priv, bdb);
1304	parse_edp(dev_priv, bdb);
1305	parse_psr(dev_priv, bdb);
1306	parse_mipi(dev_priv, bdb);
1307	parse_ddi_ports(dev_priv, bdb);
1308
1309	if (bios)
1310		pci_unmap_rom(pdev, bios);
1311
1312	return 0;
1313}
1314
1315/* Ensure that vital registers have been initialised, even if the BIOS
1316 * is absent or just failing to do its job.
1317 */
1318void intel_setup_bios(struct drm_device *dev)
1319{
1320	struct drm_i915_private *dev_priv = dev->dev_private;
1321
1322	 /* Set the Panel Power On/Off timings if uninitialized. */
1323	if (!HAS_PCH_SPLIT(dev) &&
1324	    I915_READ(PP_ON_DELAYS) == 0 && I915_READ(PP_OFF_DELAYS) == 0) {
1325		/* Set T2 to 40ms and T5 to 200ms */
1326		I915_WRITE(PP_ON_DELAYS, 0x019007d0);
1327
1328		/* Set T3 to 35ms and Tx to 200ms */
1329		I915_WRITE(PP_OFF_DELAYS, 0x015e07d0);
1330	}
1331}
1332