xref: /dragonfly/sys/dev/drm/i915/intel_bios.c (revision 5ca0a96d)
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 
28 #include <drm/drm_dp_helper.h>
29 #include <drm/drmP.h>
30 #include <drm/i915_drm.h>
31 #include "i915_drv.h"
32 
33 #define _INTEL_BIOS_PRIVATE
34 #include "intel_vbt_defs.h"
35 
36 /**
37  * DOC: Video BIOS Table (VBT)
38  *
39  * The Video BIOS Table, or VBT, provides platform and board specific
40  * configuration information to the driver that is not discoverable or available
41  * through other means. The configuration is mostly related to display
42  * hardware. The VBT is available via the ACPI OpRegion or, on older systems, in
43  * the PCI ROM.
44  *
45  * The VBT consists of a VBT Header (defined as &struct vbt_header), a BDB
46  * Header (&struct bdb_header), and a number of BIOS Data Blocks (BDB) that
47  * contain the actual configuration information. The VBT Header, and thus the
48  * VBT, begins with "$VBT" signature. The VBT Header contains the offset of the
49  * BDB Header. The data blocks are concatenated after the BDB Header. The data
50  * blocks have a 1-byte Block ID, 2-byte Block Size, and Block Size bytes of
51  * data. (Block 53, the MIPI Sequence Block is an exception.)
52  *
53  * The driver parses the VBT during load. The relevant information is stored in
54  * driver private data for ease of use, and the actual VBT is not read after
55  * that.
56  */
57 
58 #define	SLAVE_ADDR1	0x70
59 #define	SLAVE_ADDR2	0x72
60 
61 /* Get BDB block size given a pointer to Block ID. */
62 static u32 _get_blocksize(const u8 *block_base)
63 {
64 	/* The MIPI Sequence Block v3+ has a separate size field. */
65 	if (*block_base == BDB_MIPI_SEQUENCE && *(block_base + 3) >= 3)
66 		return *((const u32 *)(block_base + 4));
67 	else
68 		return *((const u16 *)(block_base + 1));
69 }
70 
71 /* Get BDB block size give a pointer to data after Block ID and Block Size. */
72 static u32 get_blocksize(const void *block_data)
73 {
74 	return _get_blocksize(block_data - 3);
75 }
76 
77 static const void *
78 find_section(const void *_bdb, int section_id)
79 {
80 	const struct bdb_header *bdb = _bdb;
81 	const u8 *base = _bdb;
82 	int index = 0;
83 	u32 total, current_size;
84 	u8 current_id;
85 
86 	/* skip to first section */
87 	index += bdb->header_size;
88 	total = bdb->bdb_size;
89 
90 	/* walk the sections looking for section_id */
91 	while (index + 3 < total) {
92 		current_id = *(base + index);
93 		current_size = _get_blocksize(base + index);
94 		index += 3;
95 
96 		if (index + current_size > total)
97 			return NULL;
98 
99 		if (current_id == section_id)
100 			return base + index;
101 
102 		index += current_size;
103 	}
104 
105 	return NULL;
106 }
107 
108 static void
109 fill_detail_timing_data(struct drm_display_mode *panel_fixed_mode,
110 			const struct lvds_dvo_timing *dvo_timing)
111 {
112 	panel_fixed_mode->hdisplay = (dvo_timing->hactive_hi << 8) |
113 		dvo_timing->hactive_lo;
114 	panel_fixed_mode->hsync_start = panel_fixed_mode->hdisplay +
115 		((dvo_timing->hsync_off_hi << 8) | dvo_timing->hsync_off_lo);
116 	panel_fixed_mode->hsync_end = panel_fixed_mode->hsync_start +
117 		((dvo_timing->hsync_pulse_width_hi << 8) |
118 			dvo_timing->hsync_pulse_width_lo);
119 	panel_fixed_mode->htotal = panel_fixed_mode->hdisplay +
120 		((dvo_timing->hblank_hi << 8) | dvo_timing->hblank_lo);
121 
122 	panel_fixed_mode->vdisplay = (dvo_timing->vactive_hi << 8) |
123 		dvo_timing->vactive_lo;
124 	panel_fixed_mode->vsync_start = panel_fixed_mode->vdisplay +
125 		((dvo_timing->vsync_off_hi << 4) | dvo_timing->vsync_off_lo);
126 	panel_fixed_mode->vsync_end = panel_fixed_mode->vsync_start +
127 		((dvo_timing->vsync_pulse_width_hi << 4) |
128 			dvo_timing->vsync_pulse_width_lo);
129 	panel_fixed_mode->vtotal = panel_fixed_mode->vdisplay +
130 		((dvo_timing->vblank_hi << 8) | dvo_timing->vblank_lo);
131 	panel_fixed_mode->clock = dvo_timing->clock * 10;
132 	panel_fixed_mode->type = DRM_MODE_TYPE_PREFERRED;
133 
134 	if (dvo_timing->hsync_positive)
135 		panel_fixed_mode->flags |= DRM_MODE_FLAG_PHSYNC;
136 	else
137 		panel_fixed_mode->flags |= DRM_MODE_FLAG_NHSYNC;
138 
139 	if (dvo_timing->vsync_positive)
140 		panel_fixed_mode->flags |= DRM_MODE_FLAG_PVSYNC;
141 	else
142 		panel_fixed_mode->flags |= DRM_MODE_FLAG_NVSYNC;
143 
144 	panel_fixed_mode->width_mm = (dvo_timing->himage_hi << 8) |
145 		dvo_timing->himage_lo;
146 	panel_fixed_mode->height_mm = (dvo_timing->vimage_hi << 8) |
147 		dvo_timing->vimage_lo;
148 
149 	/* Some VBTs have bogus h/vtotal values */
150 	if (panel_fixed_mode->hsync_end > panel_fixed_mode->htotal)
151 		panel_fixed_mode->htotal = panel_fixed_mode->hsync_end + 1;
152 	if (panel_fixed_mode->vsync_end > panel_fixed_mode->vtotal)
153 		panel_fixed_mode->vtotal = panel_fixed_mode->vsync_end + 1;
154 
155 	drm_mode_set_name(panel_fixed_mode);
156 }
157 
158 static const struct lvds_dvo_timing *
159 get_lvds_dvo_timing(const struct bdb_lvds_lfp_data *lvds_lfp_data,
160 		    const struct bdb_lvds_lfp_data_ptrs *lvds_lfp_data_ptrs,
161 		    int index)
162 {
163 	/*
164 	 * the size of fp_timing varies on the different platform.
165 	 * So calculate the DVO timing relative offset in LVDS data
166 	 * entry to get the DVO timing entry
167 	 */
168 
169 	int lfp_data_size =
170 		lvds_lfp_data_ptrs->ptr[1].dvo_timing_offset -
171 		lvds_lfp_data_ptrs->ptr[0].dvo_timing_offset;
172 	int dvo_timing_offset =
173 		lvds_lfp_data_ptrs->ptr[0].dvo_timing_offset -
174 		lvds_lfp_data_ptrs->ptr[0].fp_timing_offset;
175 	char *entry = (char *)lvds_lfp_data->data + lfp_data_size * index;
176 
177 	return (struct lvds_dvo_timing *)(entry + dvo_timing_offset);
178 }
179 
180 /* get lvds_fp_timing entry
181  * this function may return NULL if the corresponding entry is invalid
182  */
183 static const struct lvds_fp_timing *
184 get_lvds_fp_timing(const struct bdb_header *bdb,
185 		   const struct bdb_lvds_lfp_data *data,
186 		   const struct bdb_lvds_lfp_data_ptrs *ptrs,
187 		   int index)
188 {
189 	size_t data_ofs = (const u8 *)data - (const u8 *)bdb;
190 	u16 data_size = ((const u16 *)data)[-1]; /* stored in header */
191 	size_t ofs;
192 
193 	if (index >= ARRAY_SIZE(ptrs->ptr))
194 		return NULL;
195 	ofs = ptrs->ptr[index].fp_timing_offset;
196 	if (ofs < data_ofs ||
197 	    ofs + sizeof(struct lvds_fp_timing) > data_ofs + data_size)
198 		return NULL;
199 	return (const struct lvds_fp_timing *)((const u8 *)bdb + ofs);
200 }
201 
202 /* Try to find integrated panel data */
203 static void
204 parse_lfp_panel_data(struct drm_i915_private *dev_priv,
205 		     const struct bdb_header *bdb)
206 {
207 	const struct bdb_lvds_options *lvds_options;
208 	const struct bdb_lvds_lfp_data *lvds_lfp_data;
209 	const struct bdb_lvds_lfp_data_ptrs *lvds_lfp_data_ptrs;
210 	const struct lvds_dvo_timing *panel_dvo_timing;
211 	const struct lvds_fp_timing *fp_timing;
212 	struct drm_display_mode *panel_fixed_mode;
213 	int panel_type;
214 	int drrs_mode;
215 	int ret;
216 
217 	lvds_options = find_section(bdb, BDB_LVDS_OPTIONS);
218 	if (!lvds_options)
219 		return;
220 
221 	dev_priv->vbt.lvds_dither = lvds_options->pixel_dither;
222 
223 	ret = intel_opregion_get_panel_type(dev_priv);
224 	if (ret >= 0) {
225 		WARN_ON(ret > 0xf);
226 		panel_type = ret;
227 		DRM_DEBUG_KMS("Panel type: %d (OpRegion)\n", panel_type);
228 	} else {
229 		if (lvds_options->panel_type > 0xf) {
230 			DRM_DEBUG_KMS("Invalid VBT panel type 0x%x\n",
231 				      lvds_options->panel_type);
232 			return;
233 		}
234 		panel_type = lvds_options->panel_type;
235 		DRM_DEBUG_KMS("Panel type: %d (VBT)\n", panel_type);
236 	}
237 
238 	dev_priv->vbt.panel_type = panel_type;
239 
240 	drrs_mode = (lvds_options->dps_panel_type_bits
241 				>> (panel_type * 2)) & MODE_MASK;
242 	/*
243 	 * VBT has static DRRS = 0 and seamless DRRS = 2.
244 	 * The below piece of code is required to adjust vbt.drrs_type
245 	 * to match the enum drrs_support_type.
246 	 */
247 	switch (drrs_mode) {
248 	case 0:
249 		dev_priv->vbt.drrs_type = STATIC_DRRS_SUPPORT;
250 		DRM_DEBUG_KMS("DRRS supported mode is static\n");
251 		break;
252 	case 2:
253 		dev_priv->vbt.drrs_type = SEAMLESS_DRRS_SUPPORT;
254 		DRM_DEBUG_KMS("DRRS supported mode is seamless\n");
255 		break;
256 	default:
257 		dev_priv->vbt.drrs_type = DRRS_NOT_SUPPORTED;
258 		DRM_DEBUG_KMS("DRRS not supported (VBT input)\n");
259 		break;
260 	}
261 
262 	lvds_lfp_data = find_section(bdb, BDB_LVDS_LFP_DATA);
263 	if (!lvds_lfp_data)
264 		return;
265 
266 	lvds_lfp_data_ptrs = find_section(bdb, BDB_LVDS_LFP_DATA_PTRS);
267 	if (!lvds_lfp_data_ptrs)
268 		return;
269 
270 	dev_priv->vbt.lvds_vbt = 1;
271 
272 	panel_dvo_timing = get_lvds_dvo_timing(lvds_lfp_data,
273 					       lvds_lfp_data_ptrs,
274 					       panel_type);
275 
276 	panel_fixed_mode = kzalloc(sizeof(*panel_fixed_mode), GFP_KERNEL);
277 	if (!panel_fixed_mode)
278 		return;
279 
280 	fill_detail_timing_data(panel_fixed_mode, panel_dvo_timing);
281 
282 	dev_priv->vbt.lfp_lvds_vbt_mode = panel_fixed_mode;
283 
284 	DRM_DEBUG_KMS("Found panel mode in BIOS VBT tables:\n");
285 	drm_mode_debug_printmodeline(panel_fixed_mode);
286 
287 	fp_timing = get_lvds_fp_timing(bdb, lvds_lfp_data,
288 				       lvds_lfp_data_ptrs,
289 				       panel_type);
290 	if (fp_timing) {
291 		/* check the resolution, just to be sure */
292 		if (fp_timing->x_res == panel_fixed_mode->hdisplay &&
293 		    fp_timing->y_res == panel_fixed_mode->vdisplay) {
294 			dev_priv->vbt.bios_lvds_val = fp_timing->lvds_reg_val;
295 			DRM_DEBUG_KMS("VBT initial LVDS value %x\n",
296 				      dev_priv->vbt.bios_lvds_val);
297 		}
298 	}
299 }
300 
301 static void
302 parse_lfp_backlight(struct drm_i915_private *dev_priv,
303 		    const struct bdb_header *bdb)
304 {
305 	const struct bdb_lfp_backlight_data *backlight_data;
306 	const struct bdb_lfp_backlight_data_entry *entry;
307 	int panel_type = dev_priv->vbt.panel_type;
308 
309 	backlight_data = find_section(bdb, BDB_LVDS_BACKLIGHT);
310 	if (!backlight_data)
311 		return;
312 
313 	if (backlight_data->entry_size != sizeof(backlight_data->data[0])) {
314 		DRM_DEBUG_KMS("Unsupported backlight data entry size %u\n",
315 			      backlight_data->entry_size);
316 		return;
317 	}
318 
319 	entry = &backlight_data->data[panel_type];
320 
321 	dev_priv->vbt.backlight.present = entry->type == BDB_BACKLIGHT_TYPE_PWM;
322 	if (!dev_priv->vbt.backlight.present) {
323 		DRM_DEBUG_KMS("PWM backlight not present in VBT (type %u)\n",
324 			      entry->type);
325 		return;
326 	}
327 
328 	dev_priv->vbt.backlight.type = INTEL_BACKLIGHT_DISPLAY_DDI;
329 	if (bdb->version >= 191 &&
330 	    get_blocksize(backlight_data) >= sizeof(*backlight_data)) {
331 		const struct bdb_lfp_backlight_control_method *method;
332 
333 		method = &backlight_data->backlight_control[panel_type];
334 		dev_priv->vbt.backlight.type = method->type;
335 		dev_priv->vbt.backlight.controller = method->controller;
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, controller %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 		      dev_priv->vbt.backlight.controller);
348 }
349 
350 /* Try to find sdvo panel data */
351 static void
352 parse_sdvo_panel_data(struct drm_i915_private *dev_priv,
353 		      const struct bdb_header *bdb)
354 {
355 	const struct lvds_dvo_timing *dvo_timing;
356 	struct drm_display_mode *panel_fixed_mode;
357 	int index;
358 
359 	index = i915_modparams.vbt_sdvo_panel_type;
360 	if (index == -2) {
361 		DRM_DEBUG_KMS("Ignore SDVO panel mode from BIOS VBT tables.\n");
362 		return;
363 	}
364 
365 	if (index == -1) {
366 		const struct bdb_sdvo_lvds_options *sdvo_lvds_options;
367 
368 		sdvo_lvds_options = find_section(bdb, BDB_SDVO_LVDS_OPTIONS);
369 		if (!sdvo_lvds_options)
370 			return;
371 
372 		index = sdvo_lvds_options->panel_type;
373 	}
374 
375 	dvo_timing = find_section(bdb, BDB_SDVO_PANEL_DTDS);
376 	if (!dvo_timing)
377 		return;
378 
379 	panel_fixed_mode = kzalloc(sizeof(*panel_fixed_mode), GFP_KERNEL);
380 	if (!panel_fixed_mode)
381 		return;
382 
383 	fill_detail_timing_data(panel_fixed_mode, dvo_timing + index);
384 
385 	dev_priv->vbt.sdvo_lvds_vbt_mode = panel_fixed_mode;
386 
387 	DRM_DEBUG_KMS("Found SDVO panel mode in BIOS VBT tables:\n");
388 	drm_mode_debug_printmodeline(panel_fixed_mode);
389 }
390 
391 static int intel_bios_ssc_frequency(struct drm_i915_private *dev_priv,
392 				    bool alternate)
393 {
394 	switch (INTEL_INFO(dev_priv)->gen) {
395 	case 2:
396 		return alternate ? 66667 : 48000;
397 	case 3:
398 	case 4:
399 		return alternate ? 100000 : 96000;
400 	default:
401 		return alternate ? 100000 : 120000;
402 	}
403 }
404 
405 static void
406 parse_general_features(struct drm_i915_private *dev_priv,
407 		       const struct bdb_header *bdb)
408 {
409 	const struct bdb_general_features *general;
410 
411 	general = find_section(bdb, BDB_GENERAL_FEATURES);
412 	if (!general)
413 		return;
414 
415 	dev_priv->vbt.int_tv_support = general->int_tv_support;
416 	/* int_crt_support can't be trusted on earlier platforms */
417 	if (bdb->version >= 155 &&
418 	    (HAS_DDI(dev_priv) || IS_VALLEYVIEW(dev_priv)))
419 		dev_priv->vbt.int_crt_support = general->int_crt_support;
420 	dev_priv->vbt.lvds_use_ssc = general->enable_ssc;
421 	dev_priv->vbt.lvds_ssc_freq =
422 		intel_bios_ssc_frequency(dev_priv, general->ssc_freq);
423 	dev_priv->vbt.display_clock_mode = general->display_clock_mode;
424 	dev_priv->vbt.fdi_rx_polarity_inverted = general->fdi_rx_polarity_inverted;
425 	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",
426 		      dev_priv->vbt.int_tv_support,
427 		      dev_priv->vbt.int_crt_support,
428 		      dev_priv->vbt.lvds_use_ssc,
429 		      dev_priv->vbt.lvds_ssc_freq,
430 		      dev_priv->vbt.display_clock_mode,
431 		      dev_priv->vbt.fdi_rx_polarity_inverted);
432 }
433 
434 static const struct child_device_config *
435 child_device_ptr(const struct bdb_general_definitions *defs, int i)
436 {
437 	return (const void *) &defs->devices[i * defs->child_dev_size];
438 }
439 
440 static void
441 parse_sdvo_device_mapping(struct drm_i915_private *dev_priv, u8 bdb_version)
442 {
443 	struct sdvo_device_mapping *mapping;
444 	const struct child_device_config *child;
445 	int i, count = 0;
446 
447 	/*
448 	 * Only parse SDVO mappings on gens that could have SDVO. This isn't
449 	 * accurate and doesn't have to be, as long as it's not too strict.
450 	 */
451 	if (!IS_GEN(dev_priv, 3, 7)) {
452 		DRM_DEBUG_KMS("Skipping SDVO device mapping\n");
453 		return;
454 	}
455 
456 	for (i = 0, count = 0; i < dev_priv->vbt.child_dev_num; i++) {
457 		child = dev_priv->vbt.child_dev + i;
458 
459 		if (child->slave_addr != SLAVE_ADDR1 &&
460 		    child->slave_addr != SLAVE_ADDR2) {
461 			/*
462 			 * If the slave address is neither 0x70 nor 0x72,
463 			 * it is not a SDVO device. Skip it.
464 			 */
465 			continue;
466 		}
467 		if (child->dvo_port != DEVICE_PORT_DVOB &&
468 		    child->dvo_port != DEVICE_PORT_DVOC) {
469 			/* skip the incorrect SDVO port */
470 			DRM_DEBUG_KMS("Incorrect SDVO port. Skip it\n");
471 			continue;
472 		}
473 		DRM_DEBUG_KMS("the SDVO device with slave addr %2x is found on"
474 			      " %s port\n",
475 			      child->slave_addr,
476 			      (child->dvo_port == DEVICE_PORT_DVOB) ?
477 			      "SDVOB" : "SDVOC");
478 		mapping = &dev_priv->vbt.sdvo_mappings[child->dvo_port - 1];
479 		if (!mapping->initialized) {
480 			mapping->dvo_port = child->dvo_port;
481 			mapping->slave_addr = child->slave_addr;
482 			mapping->dvo_wiring = child->dvo_wiring;
483 			mapping->ddc_pin = child->ddc_pin;
484 			mapping->i2c_pin = child->i2c_pin;
485 			mapping->initialized = 1;
486 			DRM_DEBUG_KMS("SDVO device: dvo=%x, addr=%x, wiring=%d, ddc_pin=%d, i2c_pin=%d\n",
487 				      mapping->dvo_port,
488 				      mapping->slave_addr,
489 				      mapping->dvo_wiring,
490 				      mapping->ddc_pin,
491 				      mapping->i2c_pin);
492 		} else {
493 			DRM_DEBUG_KMS("Maybe one SDVO port is shared by "
494 					 "two SDVO device.\n");
495 		}
496 		if (child->slave2_addr) {
497 			/* Maybe this is a SDVO device with multiple inputs */
498 			/* And the mapping info is not added */
499 			DRM_DEBUG_KMS("there exists the slave2_addr. Maybe this"
500 				" is a SDVO device with multiple inputs.\n");
501 		}
502 		count++;
503 	}
504 
505 	if (!count) {
506 		/* No SDVO device info is found */
507 		DRM_DEBUG_KMS("No SDVO device info is found in VBT\n");
508 	}
509 }
510 
511 static void
512 parse_driver_features(struct drm_i915_private *dev_priv,
513 		      const struct bdb_header *bdb)
514 {
515 	const struct bdb_driver_features *driver;
516 
517 	driver = find_section(bdb, BDB_DRIVER_FEATURES);
518 	if (!driver)
519 		return;
520 
521 	if (driver->lvds_config == BDB_DRIVER_FEATURE_EDP)
522 		dev_priv->vbt.edp.support = 1;
523 
524 	DRM_DEBUG_KMS("DRRS State Enabled:%d\n", driver->drrs_enabled);
525 	/*
526 	 * If DRRS is not supported, drrs_type has to be set to 0.
527 	 * This is because, VBT is configured in such a way that
528 	 * static DRRS is 0 and DRRS not supported is represented by
529 	 * driver->drrs_enabled=false
530 	 */
531 	if (!driver->drrs_enabled)
532 		dev_priv->vbt.drrs_type = DRRS_NOT_SUPPORTED;
533 }
534 
535 static void
536 parse_edp(struct drm_i915_private *dev_priv, const struct bdb_header *bdb)
537 {
538 	const struct bdb_edp *edp;
539 	const struct edp_power_seq *edp_pps;
540 	const struct edp_fast_link_params *edp_link_params;
541 	int panel_type = dev_priv->vbt.panel_type;
542 
543 	edp = find_section(bdb, BDB_EDP);
544 	if (!edp) {
545 		if (dev_priv->vbt.edp.support)
546 			DRM_DEBUG_KMS("No eDP BDB found but eDP panel supported.\n");
547 		return;
548 	}
549 
550 	switch ((edp->color_depth >> (panel_type * 2)) & 3) {
551 	case EDP_18BPP:
552 		dev_priv->vbt.edp.bpp = 18;
553 		break;
554 	case EDP_24BPP:
555 		dev_priv->vbt.edp.bpp = 24;
556 		break;
557 	case EDP_30BPP:
558 		dev_priv->vbt.edp.bpp = 30;
559 		break;
560 	}
561 
562 	/* Get the eDP sequencing and link info */
563 	edp_pps = &edp->power_seqs[panel_type];
564 	edp_link_params = &edp->fast_link_params[panel_type];
565 
566 	dev_priv->vbt.edp.pps = *edp_pps;
567 
568 	switch (edp_link_params->rate) {
569 	case EDP_RATE_1_62:
570 		dev_priv->vbt.edp.rate = DP_LINK_BW_1_62;
571 		break;
572 	case EDP_RATE_2_7:
573 		dev_priv->vbt.edp.rate = DP_LINK_BW_2_7;
574 		break;
575 	default:
576 		DRM_DEBUG_KMS("VBT has unknown eDP link rate value %u\n",
577 			      edp_link_params->rate);
578 		break;
579 	}
580 
581 	switch (edp_link_params->lanes) {
582 	case EDP_LANE_1:
583 		dev_priv->vbt.edp.lanes = 1;
584 		break;
585 	case EDP_LANE_2:
586 		dev_priv->vbt.edp.lanes = 2;
587 		break;
588 	case EDP_LANE_4:
589 		dev_priv->vbt.edp.lanes = 4;
590 		break;
591 	default:
592 		DRM_DEBUG_KMS("VBT has unknown eDP lane count value %u\n",
593 			      edp_link_params->lanes);
594 		break;
595 	}
596 
597 	switch (edp_link_params->preemphasis) {
598 	case EDP_PREEMPHASIS_NONE:
599 		dev_priv->vbt.edp.preemphasis = DP_TRAIN_PRE_EMPH_LEVEL_0;
600 		break;
601 	case EDP_PREEMPHASIS_3_5dB:
602 		dev_priv->vbt.edp.preemphasis = DP_TRAIN_PRE_EMPH_LEVEL_1;
603 		break;
604 	case EDP_PREEMPHASIS_6dB:
605 		dev_priv->vbt.edp.preemphasis = DP_TRAIN_PRE_EMPH_LEVEL_2;
606 		break;
607 	case EDP_PREEMPHASIS_9_5dB:
608 		dev_priv->vbt.edp.preemphasis = DP_TRAIN_PRE_EMPH_LEVEL_3;
609 		break;
610 	default:
611 		DRM_DEBUG_KMS("VBT has unknown eDP pre-emphasis value %u\n",
612 			      edp_link_params->preemphasis);
613 		break;
614 	}
615 
616 	switch (edp_link_params->vswing) {
617 	case EDP_VSWING_0_4V:
618 		dev_priv->vbt.edp.vswing = DP_TRAIN_VOLTAGE_SWING_LEVEL_0;
619 		break;
620 	case EDP_VSWING_0_6V:
621 		dev_priv->vbt.edp.vswing = DP_TRAIN_VOLTAGE_SWING_LEVEL_1;
622 		break;
623 	case EDP_VSWING_0_8V:
624 		dev_priv->vbt.edp.vswing = DP_TRAIN_VOLTAGE_SWING_LEVEL_2;
625 		break;
626 	case EDP_VSWING_1_2V:
627 		dev_priv->vbt.edp.vswing = DP_TRAIN_VOLTAGE_SWING_LEVEL_3;
628 		break;
629 	default:
630 		DRM_DEBUG_KMS("VBT has unknown eDP voltage swing value %u\n",
631 			      edp_link_params->vswing);
632 		break;
633 	}
634 
635 	if (bdb->version >= 173) {
636 		uint8_t vswing;
637 
638 		/* Don't read from VBT if module parameter has valid value*/
639 		if (i915_modparams.edp_vswing) {
640 			dev_priv->vbt.edp.low_vswing =
641 				i915_modparams.edp_vswing == 1;
642 		} else {
643 			vswing = (edp->edp_vswing_preemph >> (panel_type * 4)) & 0xF;
644 			dev_priv->vbt.edp.low_vswing = vswing == 0;
645 		}
646 	}
647 }
648 
649 static void
650 parse_psr(struct drm_i915_private *dev_priv, const struct bdb_header *bdb)
651 {
652 	const struct bdb_psr *psr;
653 	const struct psr_table *psr_table;
654 	int panel_type = dev_priv->vbt.panel_type;
655 
656 	psr = find_section(bdb, BDB_PSR);
657 	if (!psr) {
658 		DRM_DEBUG_KMS("No PSR BDB found.\n");
659 		return;
660 	}
661 
662 	psr_table = &psr->psr_table[panel_type];
663 
664 	dev_priv->vbt.psr.full_link = psr_table->full_link;
665 	dev_priv->vbt.psr.require_aux_wakeup = psr_table->require_aux_to_wakeup;
666 
667 	/* Allowed VBT values goes from 0 to 15 */
668 	dev_priv->vbt.psr.idle_frames = psr_table->idle_frames < 0 ? 0 :
669 		psr_table->idle_frames > 15 ? 15 : psr_table->idle_frames;
670 
671 	switch (psr_table->lines_to_wait) {
672 	case 0:
673 		dev_priv->vbt.psr.lines_to_wait = PSR_0_LINES_TO_WAIT;
674 		break;
675 	case 1:
676 		dev_priv->vbt.psr.lines_to_wait = PSR_1_LINE_TO_WAIT;
677 		break;
678 	case 2:
679 		dev_priv->vbt.psr.lines_to_wait = PSR_4_LINES_TO_WAIT;
680 		break;
681 	case 3:
682 		dev_priv->vbt.psr.lines_to_wait = PSR_8_LINES_TO_WAIT;
683 		break;
684 	default:
685 		DRM_DEBUG_KMS("VBT has unknown PSR lines to wait %u\n",
686 			      psr_table->lines_to_wait);
687 		break;
688 	}
689 
690 	dev_priv->vbt.psr.tp1_wakeup_time = psr_table->tp1_wakeup_time;
691 	dev_priv->vbt.psr.tp2_tp3_wakeup_time = psr_table->tp2_tp3_wakeup_time;
692 }
693 
694 static void parse_dsi_backlight_ports(struct drm_i915_private *dev_priv,
695 				      u16 version, enum port port)
696 {
697 	if (!dev_priv->vbt.dsi.config->dual_link || version < 197) {
698 		dev_priv->vbt.dsi.bl_ports = BIT(port);
699 		if (dev_priv->vbt.dsi.config->cabc_supported)
700 			dev_priv->vbt.dsi.cabc_ports = BIT(port);
701 
702 		return;
703 	}
704 
705 	switch (dev_priv->vbt.dsi.config->dl_dcs_backlight_ports) {
706 	case DL_DCS_PORT_A:
707 		dev_priv->vbt.dsi.bl_ports = BIT(PORT_A);
708 		break;
709 	case DL_DCS_PORT_C:
710 		dev_priv->vbt.dsi.bl_ports = BIT(PORT_C);
711 		break;
712 	default:
713 	case DL_DCS_PORT_A_AND_C:
714 		dev_priv->vbt.dsi.bl_ports = BIT(PORT_A) | BIT(PORT_C);
715 		break;
716 	}
717 
718 	if (!dev_priv->vbt.dsi.config->cabc_supported)
719 		return;
720 
721 	switch (dev_priv->vbt.dsi.config->dl_dcs_cabc_ports) {
722 	case DL_DCS_PORT_A:
723 		dev_priv->vbt.dsi.cabc_ports = BIT(PORT_A);
724 		break;
725 	case DL_DCS_PORT_C:
726 		dev_priv->vbt.dsi.cabc_ports = BIT(PORT_C);
727 		break;
728 	default:
729 	case DL_DCS_PORT_A_AND_C:
730 		dev_priv->vbt.dsi.cabc_ports =
731 					BIT(PORT_A) | BIT(PORT_C);
732 		break;
733 	}
734 }
735 
736 static void
737 parse_mipi_config(struct drm_i915_private *dev_priv,
738 		  const struct bdb_header *bdb)
739 {
740 	const struct bdb_mipi_config *start;
741 	const struct mipi_config *config;
742 	const struct mipi_pps_data *pps;
743 	int panel_type = dev_priv->vbt.panel_type;
744 	enum port port;
745 
746 	/* parse MIPI blocks only if LFP type is MIPI */
747 	if (!intel_bios_is_dsi_present(dev_priv, &port))
748 		return;
749 
750 	/* Initialize this to undefined indicating no generic MIPI support */
751 	dev_priv->vbt.dsi.panel_id = MIPI_DSI_UNDEFINED_PANEL_ID;
752 
753 	/* Block #40 is already parsed and panel_fixed_mode is
754 	 * stored in dev_priv->lfp_lvds_vbt_mode
755 	 * resuse this when needed
756 	 */
757 
758 	/* Parse #52 for panel index used from panel_type already
759 	 * parsed
760 	 */
761 	start = find_section(bdb, BDB_MIPI_CONFIG);
762 	if (!start) {
763 		DRM_DEBUG_KMS("No MIPI config BDB found");
764 		return;
765 	}
766 
767 	DRM_DEBUG_DRIVER("Found MIPI Config block, panel index = %d\n",
768 								panel_type);
769 
770 	/*
771 	 * get hold of the correct configuration block and pps data as per
772 	 * the panel_type as index
773 	 */
774 	config = &start->config[panel_type];
775 	pps = &start->pps[panel_type];
776 
777 	/* store as of now full data. Trim when we realise all is not needed */
778 	dev_priv->vbt.dsi.config = kmemdup(config, sizeof(struct mipi_config), GFP_KERNEL);
779 	if (!dev_priv->vbt.dsi.config)
780 		return;
781 
782 	dev_priv->vbt.dsi.pps = kmemdup(pps, sizeof(struct mipi_pps_data), GFP_KERNEL);
783 	if (!dev_priv->vbt.dsi.pps) {
784 		kfree(dev_priv->vbt.dsi.config);
785 		return;
786 	}
787 
788 	parse_dsi_backlight_ports(dev_priv, bdb->version, port);
789 
790 	/* We have mandatory mipi config blocks. Initialize as generic panel */
791 	dev_priv->vbt.dsi.panel_id = MIPI_DSI_GENERIC_PANEL_ID;
792 }
793 
794 /* Find the sequence block and size for the given panel. */
795 static const u8 *
796 find_panel_sequence_block(const struct bdb_mipi_sequence *sequence,
797 			  u16 panel_id, u32 *seq_size)
798 {
799 	u32 total = get_blocksize(sequence);
800 	const u8 *data = &sequence->data[0];
801 	u8 current_id;
802 	u32 current_size;
803 	int header_size = sequence->version >= 3 ? 5 : 3;
804 	int index = 0;
805 	int i;
806 
807 	/* skip new block size */
808 	if (sequence->version >= 3)
809 		data += 4;
810 
811 	for (i = 0; i < MAX_MIPI_CONFIGURATIONS && index < total; i++) {
812 		if (index + header_size > total) {
813 			DRM_ERROR("Invalid sequence block (header)\n");
814 			return NULL;
815 		}
816 
817 		current_id = *(data + index);
818 		if (sequence->version >= 3)
819 			current_size = *((const u32 *)(data + index + 1));
820 		else
821 			current_size = *((const u16 *)(data + index + 1));
822 
823 		index += header_size;
824 
825 		if (index + current_size > total) {
826 			DRM_ERROR("Invalid sequence block\n");
827 			return NULL;
828 		}
829 
830 		if (current_id == panel_id) {
831 			*seq_size = current_size;
832 			return data + index;
833 		}
834 
835 		index += current_size;
836 	}
837 
838 	DRM_ERROR("Sequence block detected but no valid configuration\n");
839 
840 	return NULL;
841 }
842 
843 static int goto_next_sequence(const u8 *data, int index, int total)
844 {
845 	u16 len;
846 
847 	/* Skip Sequence Byte. */
848 	for (index = index + 1; index < total; index += len) {
849 		u8 operation_byte = *(data + index);
850 		index++;
851 
852 		switch (operation_byte) {
853 		case MIPI_SEQ_ELEM_END:
854 			return index;
855 		case MIPI_SEQ_ELEM_SEND_PKT:
856 			if (index + 4 > total)
857 				return 0;
858 
859 			len = *((const u16 *)(data + index + 2)) + 4;
860 			break;
861 		case MIPI_SEQ_ELEM_DELAY:
862 			len = 4;
863 			break;
864 		case MIPI_SEQ_ELEM_GPIO:
865 			len = 2;
866 			break;
867 		case MIPI_SEQ_ELEM_I2C:
868 			if (index + 7 > total)
869 				return 0;
870 			len = *(data + index + 6) + 7;
871 			break;
872 		default:
873 			DRM_ERROR("Unknown operation byte\n");
874 			return 0;
875 		}
876 	}
877 
878 	return 0;
879 }
880 
881 static int goto_next_sequence_v3(const u8 *data, int index, int total)
882 {
883 	int seq_end;
884 	u16 len;
885 	u32 size_of_sequence;
886 
887 	/*
888 	 * Could skip sequence based on Size of Sequence alone, but also do some
889 	 * checking on the structure.
890 	 */
891 	if (total < 5) {
892 		DRM_ERROR("Too small sequence size\n");
893 		return 0;
894 	}
895 
896 	/* Skip Sequence Byte. */
897 	index++;
898 
899 	/*
900 	 * Size of Sequence. Excludes the Sequence Byte and the size itself,
901 	 * includes MIPI_SEQ_ELEM_END byte, excludes the final MIPI_SEQ_END
902 	 * byte.
903 	 */
904 	size_of_sequence = *((const uint32_t *)(data + index));
905 	index += 4;
906 
907 	seq_end = index + size_of_sequence;
908 	if (seq_end > total) {
909 		DRM_ERROR("Invalid sequence size\n");
910 		return 0;
911 	}
912 
913 	for (; index < total; index += len) {
914 		u8 operation_byte = *(data + index);
915 		index++;
916 
917 		if (operation_byte == MIPI_SEQ_ELEM_END) {
918 			if (index != seq_end) {
919 				DRM_ERROR("Invalid element structure\n");
920 				return 0;
921 			}
922 			return index;
923 		}
924 
925 		len = *(data + index);
926 		index++;
927 
928 		/*
929 		 * FIXME: Would be nice to check elements like for v1/v2 in
930 		 * goto_next_sequence() above.
931 		 */
932 		switch (operation_byte) {
933 		case MIPI_SEQ_ELEM_SEND_PKT:
934 		case MIPI_SEQ_ELEM_DELAY:
935 		case MIPI_SEQ_ELEM_GPIO:
936 		case MIPI_SEQ_ELEM_I2C:
937 		case MIPI_SEQ_ELEM_SPI:
938 		case MIPI_SEQ_ELEM_PMIC:
939 			break;
940 		default:
941 			DRM_ERROR("Unknown operation byte %u\n",
942 				  operation_byte);
943 			break;
944 		}
945 	}
946 
947 	return 0;
948 }
949 
950 static void
951 parse_mipi_sequence(struct drm_i915_private *dev_priv,
952 		    const struct bdb_header *bdb)
953 {
954 	int panel_type = dev_priv->vbt.panel_type;
955 	const struct bdb_mipi_sequence *sequence;
956 	const u8 *seq_data;
957 	u32 seq_size;
958 	u8 *data;
959 	int index = 0;
960 
961 	/* Only our generic panel driver uses the sequence block. */
962 	if (dev_priv->vbt.dsi.panel_id != MIPI_DSI_GENERIC_PANEL_ID)
963 		return;
964 
965 	sequence = find_section(bdb, BDB_MIPI_SEQUENCE);
966 	if (!sequence) {
967 		DRM_DEBUG_KMS("No MIPI Sequence found, parsing complete\n");
968 		return;
969 	}
970 
971 	/* Fail gracefully for forward incompatible sequence block. */
972 	if (sequence->version >= 4) {
973 		DRM_ERROR("Unable to parse MIPI Sequence Block v%u\n",
974 			  sequence->version);
975 		return;
976 	}
977 
978 	DRM_DEBUG_DRIVER("Found MIPI sequence block v%u\n", sequence->version);
979 
980 	seq_data = find_panel_sequence_block(sequence, panel_type, &seq_size);
981 	if (!seq_data)
982 		return;
983 
984 	data = kmemdup(seq_data, seq_size, GFP_KERNEL);
985 	if (!data)
986 		return;
987 
988 	/* Parse the sequences, store pointers to each sequence. */
989 	for (;;) {
990 		u8 seq_id = *(data + index);
991 		if (seq_id == MIPI_SEQ_END)
992 			break;
993 
994 		if (seq_id >= MIPI_SEQ_MAX) {
995 			DRM_ERROR("Unknown sequence %u\n", seq_id);
996 			goto err;
997 		}
998 
999 		/* Log about presence of sequences we won't run. */
1000 		if (seq_id == MIPI_SEQ_TEAR_ON || seq_id == MIPI_SEQ_TEAR_OFF)
1001 			DRM_DEBUG_KMS("Unsupported sequence %u\n", seq_id);
1002 
1003 		dev_priv->vbt.dsi.sequence[seq_id] = data + index;
1004 
1005 		if (sequence->version >= 3)
1006 			index = goto_next_sequence_v3(data, index, seq_size);
1007 		else
1008 			index = goto_next_sequence(data, index, seq_size);
1009 		if (!index) {
1010 			DRM_ERROR("Invalid sequence %u\n", seq_id);
1011 			goto err;
1012 		}
1013 	}
1014 
1015 	dev_priv->vbt.dsi.data = data;
1016 	dev_priv->vbt.dsi.size = seq_size;
1017 	dev_priv->vbt.dsi.seq_version = sequence->version;
1018 
1019 	DRM_DEBUG_DRIVER("MIPI related VBT parsing complete\n");
1020 	return;
1021 
1022 err:
1023 	kfree(data);
1024 	memset(dev_priv->vbt.dsi.sequence, 0, sizeof(dev_priv->vbt.dsi.sequence));
1025 }
1026 
1027 static u8 translate_iboost(u8 val)
1028 {
1029 	static const u8 mapping[] = { 1, 3, 7 }; /* See VBT spec */
1030 
1031 	if (val >= ARRAY_SIZE(mapping)) {
1032 		DRM_DEBUG_KMS("Unsupported I_boost value found in VBT (%d), display may not work properly\n", val);
1033 		return 0;
1034 	}
1035 	return mapping[val];
1036 }
1037 
1038 static void sanitize_ddc_pin(struct drm_i915_private *dev_priv,
1039 			     enum port port)
1040 {
1041 	const struct ddi_vbt_port_info *info =
1042 		&dev_priv->vbt.ddi_port_info[port];
1043 	enum port p;
1044 
1045 	if (!info->alternate_ddc_pin)
1046 		return;
1047 
1048 	for_each_port_masked(p, (1 << port) - 1) {
1049 		struct ddi_vbt_port_info *i = &dev_priv->vbt.ddi_port_info[p];
1050 
1051 		if (info->alternate_ddc_pin != i->alternate_ddc_pin)
1052 			continue;
1053 
1054 		DRM_DEBUG_KMS("port %c trying to use the same DDC pin (0x%x) as port %c, "
1055 			      "disabling port %c DVI/HDMI support\n",
1056 			      port_name(p), i->alternate_ddc_pin,
1057 			      port_name(port), port_name(p));
1058 
1059 		/*
1060 		 * If we have multiple ports supposedly sharing the
1061 		 * pin, then dvi/hdmi couldn't exist on the shared
1062 		 * port. Otherwise they share the same ddc bin and
1063 		 * system couldn't communicate with them separately.
1064 		 *
1065 		 * Due to parsing the ports in alphabetical order,
1066 		 * a higher port will always clobber a lower one.
1067 		 */
1068 		i->supports_dvi = false;
1069 		i->supports_hdmi = false;
1070 		i->alternate_ddc_pin = 0;
1071 	}
1072 }
1073 
1074 static void sanitize_aux_ch(struct drm_i915_private *dev_priv,
1075 			    enum port port)
1076 {
1077 	const struct ddi_vbt_port_info *info =
1078 		&dev_priv->vbt.ddi_port_info[port];
1079 	enum port p;
1080 
1081 	if (!info->alternate_aux_channel)
1082 		return;
1083 
1084 	for_each_port_masked(p, (1 << port) - 1) {
1085 		struct ddi_vbt_port_info *i = &dev_priv->vbt.ddi_port_info[p];
1086 
1087 		if (info->alternate_aux_channel != i->alternate_aux_channel)
1088 			continue;
1089 
1090 		DRM_DEBUG_KMS("port %c trying to use the same AUX CH (0x%x) as port %c, "
1091 			      "disabling port %c DP support\n",
1092 			      port_name(p), i->alternate_aux_channel,
1093 			      port_name(port), port_name(p));
1094 
1095 		/*
1096 		 * If we have multiple ports supposedlt sharing the
1097 		 * aux channel, then DP couldn't exist on the shared
1098 		 * port. Otherwise they share the same aux channel
1099 		 * and system couldn't communicate with them separately.
1100 		 *
1101 		 * Due to parsing the ports in alphabetical order,
1102 		 * a higher port will always clobber a lower one.
1103 		 */
1104 		i->supports_dp = false;
1105 		i->alternate_aux_channel = 0;
1106 	}
1107 }
1108 
1109 static const u8 cnp_ddc_pin_map[] = {
1110 	[0] = 0, /* N/A */
1111 	[DDC_BUS_DDI_B] = GMBUS_PIN_1_BXT,
1112 	[DDC_BUS_DDI_C] = GMBUS_PIN_2_BXT,
1113 	[DDC_BUS_DDI_D] = GMBUS_PIN_4_CNP, /* sic */
1114 	[DDC_BUS_DDI_F] = GMBUS_PIN_3_BXT, /* sic */
1115 };
1116 
1117 static u8 map_ddc_pin(struct drm_i915_private *dev_priv, u8 vbt_pin)
1118 {
1119 	if (HAS_PCH_CNP(dev_priv)) {
1120 		if (vbt_pin < ARRAY_SIZE(cnp_ddc_pin_map)) {
1121 			return cnp_ddc_pin_map[vbt_pin];
1122 		} else {
1123 			DRM_DEBUG_KMS("Ignoring alternate pin: VBT claims DDC pin %d, which is not valid for this platform\n", vbt_pin);
1124 			return 0;
1125 		}
1126 	}
1127 
1128 	return vbt_pin;
1129 }
1130 
1131 static void parse_ddi_port(struct drm_i915_private *dev_priv, enum port port,
1132 			   u8 bdb_version)
1133 {
1134 	struct child_device_config *it, *child = NULL;
1135 	struct ddi_vbt_port_info *info = &dev_priv->vbt.ddi_port_info[port];
1136 	uint8_t hdmi_level_shift;
1137 	int i, j;
1138 	bool is_dvi, is_hdmi, is_dp, is_edp, is_crt;
1139 	uint8_t aux_channel, ddc_pin;
1140 	/* Each DDI port can have more than one value on the "DVO Port" field,
1141 	 * so look for all the possible values for each port.
1142 	 */
1143 	int dvo_ports[][3] = {
1144 		{DVO_PORT_HDMIA, DVO_PORT_DPA, -1},
1145 		{DVO_PORT_HDMIB, DVO_PORT_DPB, -1},
1146 		{DVO_PORT_HDMIC, DVO_PORT_DPC, -1},
1147 		{DVO_PORT_HDMID, DVO_PORT_DPD, -1},
1148 		{DVO_PORT_CRT, DVO_PORT_HDMIE, DVO_PORT_DPE},
1149 	};
1150 
1151 	/*
1152 	 * Find the first child device to reference the port, report if more
1153 	 * than one found.
1154 	 */
1155 	for (i = 0; i < dev_priv->vbt.child_dev_num; i++) {
1156 		it = dev_priv->vbt.child_dev + i;
1157 
1158 		for (j = 0; j < 3; j++) {
1159 			if (dvo_ports[port][j] == -1)
1160 				break;
1161 
1162 			if (it->dvo_port == dvo_ports[port][j]) {
1163 				if (child) {
1164 					DRM_DEBUG_KMS("More than one child device for port %c in VBT, using the first.\n",
1165 						      port_name(port));
1166 				} else {
1167 					child = it;
1168 				}
1169 			}
1170 		}
1171 	}
1172 	if (!child)
1173 		return;
1174 
1175 	aux_channel = child->aux_channel;
1176 	ddc_pin = child->ddc_pin;
1177 
1178 	is_dvi = child->device_type & DEVICE_TYPE_TMDS_DVI_SIGNALING;
1179 	is_dp = child->device_type & DEVICE_TYPE_DISPLAYPORT_OUTPUT;
1180 	is_crt = child->device_type & DEVICE_TYPE_ANALOG_OUTPUT;
1181 	is_hdmi = is_dvi && (child->device_type & DEVICE_TYPE_NOT_HDMI_OUTPUT) == 0;
1182 	is_edp = is_dp && (child->device_type & DEVICE_TYPE_INTERNAL_CONNECTOR);
1183 
1184 	if (port == PORT_A && is_dvi) {
1185 		DRM_DEBUG_KMS("VBT claims port A supports DVI%s, ignoring\n",
1186 			      is_hdmi ? "/HDMI" : "");
1187 		is_dvi = false;
1188 		is_hdmi = false;
1189 	}
1190 
1191 	if (port == PORT_A && is_dvi) {
1192 		DRM_DEBUG_KMS("VBT claims port A supports DVI%s, ignoring\n",
1193 			      is_hdmi ? "/HDMI" : "");
1194 		is_dvi = false;
1195 		is_hdmi = false;
1196 	}
1197 
1198 	info->supports_dvi = is_dvi;
1199 	info->supports_hdmi = is_hdmi;
1200 	info->supports_dp = is_dp;
1201 	info->supports_edp = is_edp;
1202 
1203 	DRM_DEBUG_KMS("Port %c VBT info: DP:%d HDMI:%d DVI:%d EDP:%d CRT:%d\n",
1204 		      port_name(port), is_dp, is_hdmi, is_dvi, is_edp, is_crt);
1205 
1206 	if (is_edp && is_dvi)
1207 		DRM_DEBUG_KMS("Internal DP port %c is TMDS compatible\n",
1208 			      port_name(port));
1209 	if (is_crt && port != PORT_E)
1210 		DRM_DEBUG_KMS("Port %c is analog\n", port_name(port));
1211 	if (is_crt && (is_dvi || is_dp))
1212 		DRM_DEBUG_KMS("Analog port %c is also DP or TMDS compatible\n",
1213 			      port_name(port));
1214 	if (is_dvi && (port == PORT_A || port == PORT_E))
1215 		DRM_DEBUG_KMS("Port %c is TMDS compatible\n", port_name(port));
1216 	if (!is_dvi && !is_dp && !is_crt)
1217 		DRM_DEBUG_KMS("Port %c is not DP/TMDS/CRT compatible\n",
1218 			      port_name(port));
1219 	if (is_edp && (port == PORT_B || port == PORT_C || port == PORT_E))
1220 		DRM_DEBUG_KMS("Port %c is internal DP\n", port_name(port));
1221 
1222 	if (is_dvi) {
1223 		info->alternate_ddc_pin = map_ddc_pin(dev_priv, ddc_pin);
1224 
1225 		sanitize_ddc_pin(dev_priv, port);
1226 	}
1227 
1228 	if (is_dp) {
1229 		info->alternate_aux_channel = aux_channel;
1230 
1231 		sanitize_aux_ch(dev_priv, port);
1232 	}
1233 
1234 	if (bdb_version >= 158) {
1235 		/* The VBT HDMI level shift values match the table we have. */
1236 		hdmi_level_shift = child->hdmi_level_shifter_value;
1237 		DRM_DEBUG_KMS("VBT HDMI level shift for port %c: %d\n",
1238 			      port_name(port),
1239 			      hdmi_level_shift);
1240 		info->hdmi_level_shift = hdmi_level_shift;
1241 	}
1242 
1243 	/* Parse the I_boost config for SKL and above */
1244 	if (bdb_version >= 196 && child->iboost) {
1245 		info->dp_boost_level = translate_iboost(child->dp_iboost_level);
1246 		DRM_DEBUG_KMS("VBT (e)DP boost level for port %c: %d\n",
1247 			      port_name(port), info->dp_boost_level);
1248 		info->hdmi_boost_level = translate_iboost(child->hdmi_iboost_level);
1249 		DRM_DEBUG_KMS("VBT HDMI boost level for port %c: %d\n",
1250 			      port_name(port), info->hdmi_boost_level);
1251 	}
1252 }
1253 
1254 static void parse_ddi_ports(struct drm_i915_private *dev_priv, u8 bdb_version)
1255 {
1256 	enum port port;
1257 
1258 	if (!HAS_DDI(dev_priv) && !IS_CHERRYVIEW(dev_priv))
1259 		return;
1260 
1261 	if (!dev_priv->vbt.child_dev_num)
1262 		return;
1263 
1264 	if (bdb_version < 155)
1265 		return;
1266 
1267 	for (port = PORT_A; port < I915_MAX_PORTS; port++)
1268 		parse_ddi_port(dev_priv, port, bdb_version);
1269 }
1270 
1271 static void
1272 parse_general_definitions(struct drm_i915_private *dev_priv,
1273 			  const struct bdb_header *bdb)
1274 {
1275 	const struct bdb_general_definitions *defs;
1276 	const struct child_device_config *child;
1277 	int i, child_device_num, count;
1278 	u8 expected_size;
1279 	u16 block_size;
1280 	int bus_pin;
1281 
1282 	defs = find_section(bdb, BDB_GENERAL_DEFINITIONS);
1283 	if (!defs) {
1284 		DRM_DEBUG_KMS("No general definition block is found, no devices defined.\n");
1285 		return;
1286 	}
1287 
1288 	block_size = get_blocksize(defs);
1289 	if (block_size < sizeof(*defs)) {
1290 		DRM_DEBUG_KMS("General definitions block too small (%u)\n",
1291 			      block_size);
1292 		return;
1293 	}
1294 
1295 	bus_pin = defs->crt_ddc_gmbus_pin;
1296 	DRM_DEBUG_KMS("crt_ddc_bus_pin: %d\n", bus_pin);
1297 	if (intel_gmbus_is_valid_pin(dev_priv, bus_pin))
1298 		dev_priv->vbt.crt_ddc_pin = bus_pin;
1299 
1300 	if (bdb->version < 106) {
1301 		expected_size = 22;
1302 	} else if (bdb->version < 111) {
1303 		expected_size = 27;
1304 	} else if (bdb->version < 195) {
1305 		expected_size = LEGACY_CHILD_DEVICE_CONFIG_SIZE;
1306 	} else if (bdb->version == 195) {
1307 		expected_size = 37;
1308 	} else if (bdb->version <= 197) {
1309 		expected_size = 38;
1310 	} else {
1311 		expected_size = 38;
1312 		BUILD_BUG_ON(sizeof(*child) < 38);
1313 		DRM_DEBUG_DRIVER("Expected child device config size for VBT version %u not known; assuming %u\n",
1314 				 bdb->version, expected_size);
1315 	}
1316 
1317 	/* Flag an error for unexpected size, but continue anyway. */
1318 	if (defs->child_dev_size != expected_size)
1319 		DRM_ERROR("Unexpected child device config size %u (expected %u for VBT version %u)\n",
1320 			  defs->child_dev_size, expected_size, bdb->version);
1321 
1322 	/* The legacy sized child device config is the minimum we need. */
1323 	if (defs->child_dev_size < LEGACY_CHILD_DEVICE_CONFIG_SIZE) {
1324 		DRM_DEBUG_KMS("Child device config size %u is too small.\n",
1325 			      defs->child_dev_size);
1326 		return;
1327 	}
1328 
1329 	/* get the number of child device */
1330 	child_device_num = (block_size - sizeof(*defs)) / defs->child_dev_size;
1331 	count = 0;
1332 	/* get the number of child device that is present */
1333 	for (i = 0; i < child_device_num; i++) {
1334 		child = child_device_ptr(defs, i);
1335 		if (!child->device_type)
1336 			continue;
1337 		count++;
1338 	}
1339 	if (!count) {
1340 		DRM_DEBUG_KMS("no child dev is parsed from VBT\n");
1341 		return;
1342 	}
1343 	dev_priv->vbt.child_dev = kcalloc(count, sizeof(*child), GFP_KERNEL);
1344 	if (!dev_priv->vbt.child_dev) {
1345 		DRM_DEBUG_KMS("No memory space for child device\n");
1346 		return;
1347 	}
1348 
1349 	dev_priv->vbt.child_dev_num = count;
1350 	count = 0;
1351 	for (i = 0; i < child_device_num; i++) {
1352 		child = child_device_ptr(defs, i);
1353 		if (!child->device_type)
1354 			continue;
1355 
1356 		/*
1357 		 * Copy as much as we know (sizeof) and is available
1358 		 * (child_dev_size) of the child device. Accessing the data must
1359 		 * depend on VBT version.
1360 		 */
1361 		memcpy(dev_priv->vbt.child_dev + count, child,
1362 		       min_t(size_t, defs->child_dev_size, sizeof(*child)));
1363 		count++;
1364 	}
1365 }
1366 
1367 /* Common defaults which may be overridden by VBT. */
1368 static void
1369 init_vbt_defaults(struct drm_i915_private *dev_priv)
1370 {
1371 	enum port port;
1372 
1373 	dev_priv->vbt.crt_ddc_pin = GMBUS_PIN_VGADDC;
1374 
1375 	/* Default to having backlight */
1376 	dev_priv->vbt.backlight.present = true;
1377 
1378 	/* LFP panel data */
1379 	dev_priv->vbt.lvds_dither = 1;
1380 	dev_priv->vbt.lvds_vbt = 0;
1381 
1382 	/* SDVO panel data */
1383 	dev_priv->vbt.sdvo_lvds_vbt_mode = NULL;
1384 
1385 	/* general features */
1386 	dev_priv->vbt.int_tv_support = 1;
1387 	dev_priv->vbt.int_crt_support = 1;
1388 
1389 	/* Default to using SSC */
1390 	dev_priv->vbt.lvds_use_ssc = 1;
1391 	/*
1392 	 * Core/SandyBridge/IvyBridge use alternative (120MHz) reference
1393 	 * clock for LVDS.
1394 	 */
1395 	dev_priv->vbt.lvds_ssc_freq = intel_bios_ssc_frequency(dev_priv,
1396 			!HAS_PCH_SPLIT(dev_priv));
1397 	DRM_DEBUG_KMS("Set default to SSC at %d kHz\n", dev_priv->vbt.lvds_ssc_freq);
1398 
1399 	for (port = PORT_A; port < I915_MAX_PORTS; port++) {
1400 		struct ddi_vbt_port_info *info =
1401 			&dev_priv->vbt.ddi_port_info[port];
1402 
1403 		info->hdmi_level_shift = HDMI_LEVEL_SHIFT_UNKNOWN;
1404 	}
1405 }
1406 
1407 /* Defaults to initialize only if there is no VBT. */
1408 static void
1409 init_vbt_missing_defaults(struct drm_i915_private *dev_priv)
1410 {
1411 	enum port port;
1412 
1413 	for (port = PORT_A; port < I915_MAX_PORTS; port++) {
1414 		struct ddi_vbt_port_info *info =
1415 			&dev_priv->vbt.ddi_port_info[port];
1416 
1417 		info->supports_dvi = (port != PORT_A && port != PORT_E);
1418 		info->supports_hdmi = info->supports_dvi;
1419 		info->supports_dp = (port != PORT_E);
1420 	}
1421 }
1422 
1423 static const struct bdb_header *get_bdb_header(const struct vbt_header *vbt)
1424 {
1425 	const void *_vbt = vbt;
1426 
1427 	return _vbt + vbt->bdb_offset;
1428 }
1429 
1430 /**
1431  * intel_bios_is_valid_vbt - does the given buffer contain a valid VBT
1432  * @buf:	pointer to a buffer to validate
1433  * @size:	size of the buffer
1434  *
1435  * Returns true on valid VBT.
1436  */
1437 bool intel_bios_is_valid_vbt(const void *buf, size_t size)
1438 {
1439 	const struct vbt_header *vbt = buf;
1440 	const struct bdb_header *bdb;
1441 
1442 	if (!vbt)
1443 		return false;
1444 
1445 	if (sizeof(struct vbt_header) > size) {
1446 		DRM_DEBUG_DRIVER("VBT header incomplete\n");
1447 		return false;
1448 	}
1449 
1450 	if (memcmp(vbt->signature, "$VBT", 4)) {
1451 		DRM_DEBUG_DRIVER("VBT invalid signature\n");
1452 		return false;
1453 	}
1454 
1455 	if (range_overflows_t(size_t,
1456 			      vbt->bdb_offset,
1457 			      sizeof(struct bdb_header),
1458 			      size)) {
1459 		DRM_DEBUG_DRIVER("BDB header incomplete\n");
1460 		return false;
1461 	}
1462 
1463 	bdb = get_bdb_header(vbt);
1464 	if (range_overflows_t(size_t, vbt->bdb_offset, bdb->bdb_size, size)) {
1465 		DRM_DEBUG_DRIVER("BDB incomplete\n");
1466 		return false;
1467 	}
1468 
1469 	return vbt;
1470 }
1471 
1472 static const struct vbt_header *find_vbt(void __iomem *bios, size_t size)
1473 {
1474 	size_t i;
1475 
1476 	/* Scour memory looking for the VBT signature. */
1477 	for (i = 0; i + 4 < size; i++) {
1478 		void *vbt;
1479 
1480 		if (ioread32(bios + i) != *((const u32 *) "$VBT"))
1481 			continue;
1482 
1483 		/*
1484 		 * This is the one place where we explicitly discard the address
1485 		 * space (__iomem) of the BIOS/VBT.
1486 		 */
1487 		vbt = (void __force *) bios + i;
1488 		if (intel_bios_is_valid_vbt(vbt, size - i))
1489 			return vbt;
1490 
1491 		break;
1492 	}
1493 
1494 	return NULL;
1495 }
1496 
1497 /**
1498  * intel_bios_init - find VBT and initialize settings from the BIOS
1499  * @dev_priv: i915 device instance
1500  *
1501  * Parse and initialize settings from the Video BIOS Tables (VBT). If the VBT
1502  * was not found in ACPI OpRegion, try to find it in PCI ROM first. Also
1503  * initialize some defaults if the VBT is not present at all.
1504  */
1505 void intel_bios_init(struct drm_i915_private *dev_priv)
1506 {
1507 	struct pci_dev *pdev = dev_priv->drm.pdev;
1508 	const struct vbt_header *vbt = dev_priv->opregion.vbt;
1509 	const struct bdb_header *bdb;
1510 	u8 __iomem *bios = NULL;
1511 
1512 	if (HAS_PCH_NOP(dev_priv)) {
1513 		DRM_DEBUG_KMS("Skipping VBT init due to disabled display.\n");
1514 		return;
1515 	}
1516 
1517 	init_vbt_defaults(dev_priv);
1518 
1519 	/* If the OpRegion does not have VBT, look in PCI ROM. */
1520 	if (!vbt) {
1521 		size_t size;
1522 
1523 		bios = pci_map_rom(pdev, &size);
1524 		if (!bios)
1525 			goto out;
1526 
1527 		vbt = find_vbt(bios, size);
1528 		if (!vbt)
1529 			goto out;
1530 
1531 		DRM_DEBUG_KMS("Found valid VBT in PCI ROM\n");
1532 	}
1533 
1534 	bdb = get_bdb_header(vbt);
1535 
1536 	DRM_DEBUG_KMS("VBT signature \"%.*s\", BDB version %d\n",
1537 		      (int)sizeof(vbt->signature), vbt->signature, bdb->version);
1538 
1539 	/* Grab useful general definitions */
1540 	parse_general_features(dev_priv, bdb);
1541 	parse_general_definitions(dev_priv, bdb);
1542 	parse_lfp_panel_data(dev_priv, bdb);
1543 	parse_lfp_backlight(dev_priv, bdb);
1544 	parse_sdvo_panel_data(dev_priv, bdb);
1545 	parse_driver_features(dev_priv, bdb);
1546 	parse_edp(dev_priv, bdb);
1547 	parse_psr(dev_priv, bdb);
1548 	parse_mipi_config(dev_priv, bdb);
1549 	parse_mipi_sequence(dev_priv, bdb);
1550 
1551 	/* Further processing on pre-parsed data */
1552 	parse_sdvo_device_mapping(dev_priv, bdb->version);
1553 	parse_ddi_ports(dev_priv, bdb->version);
1554 
1555 out:
1556 	if (!vbt) {
1557 		DRM_INFO("Failed to find VBIOS tables (VBT)\n");
1558 		init_vbt_missing_defaults(dev_priv);
1559 	}
1560 
1561 	if (bios)
1562 		pci_unmap_rom(pdev, bios);
1563 }
1564 
1565 /**
1566  * intel_bios_is_tv_present - is integrated TV present in VBT
1567  * @dev_priv:	i915 device instance
1568  *
1569  * Return true if TV is present. If no child devices were parsed from VBT,
1570  * assume TV is present.
1571  */
1572 bool intel_bios_is_tv_present(struct drm_i915_private *dev_priv)
1573 {
1574 	const struct child_device_config *child;
1575 	int i;
1576 
1577 	if (!dev_priv->vbt.int_tv_support)
1578 		return false;
1579 
1580 	if (!dev_priv->vbt.child_dev_num)
1581 		return true;
1582 
1583 	for (i = 0; i < dev_priv->vbt.child_dev_num; i++) {
1584 		child = dev_priv->vbt.child_dev + i;
1585 		/*
1586 		 * If the device type is not TV, continue.
1587 		 */
1588 		switch (child->device_type) {
1589 		case DEVICE_TYPE_INT_TV:
1590 		case DEVICE_TYPE_TV:
1591 		case DEVICE_TYPE_TV_SVIDEO_COMPOSITE:
1592 			break;
1593 		default:
1594 			continue;
1595 		}
1596 		/* Only when the addin_offset is non-zero, it is regarded
1597 		 * as present.
1598 		 */
1599 		if (child->addin_offset)
1600 			return true;
1601 	}
1602 
1603 	return false;
1604 }
1605 
1606 /**
1607  * intel_bios_is_lvds_present - is LVDS present in VBT
1608  * @dev_priv:	i915 device instance
1609  * @i2c_pin:	i2c pin for LVDS if present
1610  *
1611  * Return true if LVDS is present. If no child devices were parsed from VBT,
1612  * assume LVDS is present.
1613  */
1614 bool intel_bios_is_lvds_present(struct drm_i915_private *dev_priv, u8 *i2c_pin)
1615 {
1616 	const struct child_device_config *child;
1617 	int i;
1618 
1619 	if (!dev_priv->vbt.child_dev_num)
1620 		return true;
1621 
1622 	for (i = 0; i < dev_priv->vbt.child_dev_num; i++) {
1623 		child = dev_priv->vbt.child_dev + i;
1624 
1625 		/* If the device type is not LFP, continue.
1626 		 * We have to check both the new identifiers as well as the
1627 		 * old for compatibility with some BIOSes.
1628 		 */
1629 		if (child->device_type != DEVICE_TYPE_INT_LFP &&
1630 		    child->device_type != DEVICE_TYPE_LFP)
1631 			continue;
1632 
1633 		if (intel_gmbus_is_valid_pin(dev_priv, child->i2c_pin))
1634 			*i2c_pin = child->i2c_pin;
1635 
1636 		/* However, we cannot trust the BIOS writers to populate
1637 		 * the VBT correctly.  Since LVDS requires additional
1638 		 * information from AIM blocks, a non-zero addin offset is
1639 		 * a good indicator that the LVDS is actually present.
1640 		 */
1641 		if (child->addin_offset)
1642 			return true;
1643 
1644 		/* But even then some BIOS writers perform some black magic
1645 		 * and instantiate the device without reference to any
1646 		 * additional data.  Trust that if the VBT was written into
1647 		 * the OpRegion then they have validated the LVDS's existence.
1648 		 */
1649 		if (dev_priv->opregion.vbt)
1650 			return true;
1651 	}
1652 
1653 	return false;
1654 }
1655 
1656 /**
1657  * intel_bios_is_port_present - is the specified digital port present
1658  * @dev_priv:	i915 device instance
1659  * @port:	port to check
1660  *
1661  * Return true if the device in %port is present.
1662  */
1663 bool intel_bios_is_port_present(struct drm_i915_private *dev_priv, enum port port)
1664 {
1665 	const struct child_device_config *child;
1666 	static const struct {
1667 		u16 dp, hdmi;
1668 	} port_mapping[] = {
1669 		[PORT_B] = { DVO_PORT_DPB, DVO_PORT_HDMIB, },
1670 		[PORT_C] = { DVO_PORT_DPC, DVO_PORT_HDMIC, },
1671 		[PORT_D] = { DVO_PORT_DPD, DVO_PORT_HDMID, },
1672 		[PORT_E] = { DVO_PORT_DPE, DVO_PORT_HDMIE, },
1673 	};
1674 	int i;
1675 
1676 	/* FIXME maybe deal with port A as well? */
1677 	if (WARN_ON(port == PORT_A) || port >= ARRAY_SIZE(port_mapping))
1678 		return false;
1679 
1680 	if (!dev_priv->vbt.child_dev_num)
1681 		return false;
1682 
1683 	for (i = 0; i < dev_priv->vbt.child_dev_num; i++) {
1684 		child = dev_priv->vbt.child_dev + i;
1685 
1686 		if ((child->dvo_port == port_mapping[port].dp ||
1687 		     child->dvo_port == port_mapping[port].hdmi) &&
1688 		    (child->device_type & (DEVICE_TYPE_TMDS_DVI_SIGNALING |
1689 					   DEVICE_TYPE_DISPLAYPORT_OUTPUT)))
1690 			return true;
1691 	}
1692 
1693 	return false;
1694 }
1695 
1696 /**
1697  * intel_bios_is_port_edp - is the device in given port eDP
1698  * @dev_priv:	i915 device instance
1699  * @port:	port to check
1700  *
1701  * Return true if the device in %port is eDP.
1702  */
1703 bool intel_bios_is_port_edp(struct drm_i915_private *dev_priv, enum port port)
1704 {
1705 	const struct child_device_config *child;
1706 	static const short port_mapping[] = {
1707 		[PORT_B] = DVO_PORT_DPB,
1708 		[PORT_C] = DVO_PORT_DPC,
1709 		[PORT_D] = DVO_PORT_DPD,
1710 		[PORT_E] = DVO_PORT_DPE,
1711 	};
1712 	int i;
1713 
1714 	if (HAS_DDI(dev_priv))
1715 		return dev_priv->vbt.ddi_port_info[port].supports_edp;
1716 
1717 	if (!dev_priv->vbt.child_dev_num)
1718 		return false;
1719 
1720 	for (i = 0; i < dev_priv->vbt.child_dev_num; i++) {
1721 		child = dev_priv->vbt.child_dev + i;
1722 
1723 		if (child->dvo_port == port_mapping[port] &&
1724 		    (child->device_type & DEVICE_TYPE_eDP_BITS) ==
1725 		    (DEVICE_TYPE_eDP & DEVICE_TYPE_eDP_BITS))
1726 			return true;
1727 	}
1728 
1729 	return false;
1730 }
1731 
1732 static bool child_dev_is_dp_dual_mode(const struct child_device_config *child,
1733 				      enum port port)
1734 {
1735 	static const struct {
1736 		u16 dp, hdmi;
1737 	} port_mapping[] = {
1738 		/*
1739 		 * Buggy VBTs may declare DP ports as having
1740 		 * HDMI type dvo_port :( So let's check both.
1741 		 */
1742 		[PORT_B] = { DVO_PORT_DPB, DVO_PORT_HDMIB, },
1743 		[PORT_C] = { DVO_PORT_DPC, DVO_PORT_HDMIC, },
1744 		[PORT_D] = { DVO_PORT_DPD, DVO_PORT_HDMID, },
1745 		[PORT_E] = { DVO_PORT_DPE, DVO_PORT_HDMIE, },
1746 	};
1747 
1748 	if (port == PORT_A || port >= ARRAY_SIZE(port_mapping))
1749 		return false;
1750 
1751 	if ((child->device_type & DEVICE_TYPE_DP_DUAL_MODE_BITS) !=
1752 	    (DEVICE_TYPE_DP_DUAL_MODE & DEVICE_TYPE_DP_DUAL_MODE_BITS))
1753 		return false;
1754 
1755 	if (child->dvo_port == port_mapping[port].dp)
1756 		return true;
1757 
1758 	/* Only accept a HDMI dvo_port as DP++ if it has an AUX channel */
1759 	if (child->dvo_port == port_mapping[port].hdmi &&
1760 	    child->aux_channel != 0)
1761 		return true;
1762 
1763 	return false;
1764 }
1765 
1766 bool intel_bios_is_port_dp_dual_mode(struct drm_i915_private *dev_priv,
1767 				     enum port port)
1768 {
1769 	const struct child_device_config *child;
1770 	int i;
1771 
1772 	for (i = 0; i < dev_priv->vbt.child_dev_num; i++) {
1773 		child = dev_priv->vbt.child_dev + i;
1774 
1775 		if (child_dev_is_dp_dual_mode(child, port))
1776 			return true;
1777 	}
1778 
1779 	return false;
1780 }
1781 
1782 /**
1783  * intel_bios_is_dsi_present - is DSI present in VBT
1784  * @dev_priv:	i915 device instance
1785  * @port:	port for DSI if present
1786  *
1787  * Return true if DSI is present, and return the port in %port.
1788  */
1789 bool intel_bios_is_dsi_present(struct drm_i915_private *dev_priv,
1790 			       enum port *port)
1791 {
1792 	const struct child_device_config *child;
1793 	u8 dvo_port;
1794 	int i;
1795 
1796 	for (i = 0; i < dev_priv->vbt.child_dev_num; i++) {
1797 		child = dev_priv->vbt.child_dev + i;
1798 
1799 		if (!(child->device_type & DEVICE_TYPE_MIPI_OUTPUT))
1800 			continue;
1801 
1802 		dvo_port = child->dvo_port;
1803 
1804 		switch (dvo_port) {
1805 		case DVO_PORT_MIPIA:
1806 		case DVO_PORT_MIPIC:
1807 			if (port)
1808 				*port = dvo_port - DVO_PORT_MIPIA;
1809 			return true;
1810 		case DVO_PORT_MIPIB:
1811 		case DVO_PORT_MIPID:
1812 			DRM_DEBUG_KMS("VBT has unsupported DSI port %c\n",
1813 				      port_name(dvo_port - DVO_PORT_MIPIA));
1814 			break;
1815 		}
1816 	}
1817 
1818 	return false;
1819 }
1820 
1821 /**
1822  * intel_bios_is_port_hpd_inverted - is HPD inverted for %port
1823  * @dev_priv:	i915 device instance
1824  * @port:	port to check
1825  *
1826  * Return true if HPD should be inverted for %port.
1827  */
1828 bool
1829 intel_bios_is_port_hpd_inverted(struct drm_i915_private *dev_priv,
1830 				enum port port)
1831 {
1832 	const struct child_device_config *child;
1833 	int i;
1834 
1835 	if (WARN_ON_ONCE(!IS_GEN9_LP(dev_priv)))
1836 		return false;
1837 
1838 	for (i = 0; i < dev_priv->vbt.child_dev_num; i++) {
1839 		child = dev_priv->vbt.child_dev + i;
1840 
1841 		if (!child->hpd_invert)
1842 			continue;
1843 
1844 		switch (child->dvo_port) {
1845 		case DVO_PORT_DPA:
1846 		case DVO_PORT_HDMIA:
1847 			if (port == PORT_A)
1848 				return true;
1849 			break;
1850 		case DVO_PORT_DPB:
1851 		case DVO_PORT_HDMIB:
1852 			if (port == PORT_B)
1853 				return true;
1854 			break;
1855 		case DVO_PORT_DPC:
1856 		case DVO_PORT_HDMIC:
1857 			if (port == PORT_C)
1858 				return true;
1859 			break;
1860 		default:
1861 			break;
1862 		}
1863 	}
1864 
1865 	return false;
1866 }
1867 
1868 /**
1869  * intel_bios_is_lspcon_present - if LSPCON is attached on %port
1870  * @dev_priv:	i915 device instance
1871  * @port:	port to check
1872  *
1873  * Return true if LSPCON is present on this port
1874  */
1875 bool
1876 intel_bios_is_lspcon_present(struct drm_i915_private *dev_priv,
1877 				enum port port)
1878 {
1879 	const struct child_device_config *child;
1880 	int i;
1881 
1882 	if (!HAS_LSPCON(dev_priv))
1883 		return false;
1884 
1885 	for (i = 0; i < dev_priv->vbt.child_dev_num; i++) {
1886 		child = dev_priv->vbt.child_dev + i;
1887 
1888 		if (!child->lspcon)
1889 			continue;
1890 
1891 		switch (child->dvo_port) {
1892 		case DVO_PORT_DPA:
1893 		case DVO_PORT_HDMIA:
1894 			if (port == PORT_A)
1895 				return true;
1896 			break;
1897 		case DVO_PORT_DPB:
1898 		case DVO_PORT_HDMIB:
1899 			if (port == PORT_B)
1900 				return true;
1901 			break;
1902 		case DVO_PORT_DPC:
1903 		case DVO_PORT_HDMIC:
1904 			if (port == PORT_C)
1905 				return true;
1906 			break;
1907 		case DVO_PORT_DPD:
1908 		case DVO_PORT_HDMID:
1909 			if (port == PORT_D)
1910 				return true;
1911 			break;
1912 		default:
1913 			break;
1914 		}
1915 	}
1916 
1917 	return false;
1918 }
1919