drivers/gpu/drm/i915/intel_bios.c

   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 "drmP.h"
  30 #include "drm.h"
  31 #include "i915_drm.h"
  32 #include "i915_drv.h"
  33 #include "intel_bios.h"
  34
  35 #define SLAVE_ADDR1     0x70
  36 #define SLAVE_ADDR2     0x72
  37
  38 static int panel_type;
  39
  40 static void *
  41 find_section(struct bdb_header *bdb, int section_id)
  42 {
  43         u8 *base = (u8 *)bdb;
  44         int index = 0;
  45         u16 total, current_size;
  46         u8 current_id;
  47
  48         /* skip to first section */
  49         index += bdb->header_size;
  50         total = bdb->bdb_size;
  51
  52         /* walk the sections looking for section_id */
  53         while (index < total) {
  54                 current_id = *(base + index);
  55                 index++;
  56                 current_size = *((u16 *)(base + index));
  57                 index += 2;
  58                 if (current_id == section_id)
  59                         return base + index;
  60                 index += current_size;
  61         }
  62
  63         return NULL;
  64 }
  65
  66 static u16
  67 get_blocksize(void *p)
  68 {
  69         u16 *block_ptr, block_size;
  70
  71         block_ptr = (u16 *)((char *)p - 2);
  72         block_size = *block_ptr;
  73         return block_size;
  74 }
  75
  76 static void
  77 fill_detail_timing_data(struct drm_display_mode *panel_fixed_mode,
  78                         const struct lvds_dvo_timing *dvo_timing)
  79 {
  80         panel_fixed_mode->hdisplay = (dvo_timing->hactive_hi << 8) |
  81                 dvo_timing->hactive_lo;
  82         panel_fixed_mode->hsync_start = panel_fixed_mode->hdisplay +
  83                 ((dvo_timing->hsync_off_hi << 8) | dvo_timing->hsync_off_lo);
  84         panel_fixed_mode->hsync_end = panel_fixed_mode->hsync_start +
  85                 dvo_timing->hsync_pulse_width;
  86         panel_fixed_mode->htotal = panel_fixed_mode->hdisplay +
  87                 ((dvo_timing->hblank_hi << 8) | dvo_timing->hblank_lo);
  88
  89         panel_fixed_mode->vdisplay = (dvo_timing->vactive_hi << 8) |
  90                 dvo_timing->vactive_lo;
  91         panel_fixed_mode->vsync_start = panel_fixed_mode->vdisplay +
  92                 dvo_timing->vsync_off;
  93         panel_fixed_mode->vsync_end = panel_fixed_mode->vsync_start +
  94                 dvo_timing->vsync_pulse_width;
  95         panel_fixed_mode->vtotal = panel_fixed_mode->vdisplay +
  96                 ((dvo_timing->vblank_hi << 8) | dvo_timing->vblank_lo);
  97         panel_fixed_mode->clock = dvo_timing->clock * 10;
  98         panel_fixed_mode->type = DRM_MODE_TYPE_PREFERRED;
  99
 100         if (dvo_timing->hsync_positive)
 101                 panel_fixed_mode->flags |= DRM_MODE_FLAG_PHSYNC;
 102         else
 103                 panel_fixed_mode->flags |= DRM_MODE_FLAG_NHSYNC;
 104
 105         if (dvo_timing->vsync_positive)
 106                 panel_fixed_mode->flags |= DRM_MODE_FLAG_PVSYNC;
 107         else
 108                 panel_fixed_mode->flags |= DRM_MODE_FLAG_NVSYNC;
 109
 110         /* Some VBTs have bogus h/vtotal values */
 111         if (panel_fixed_mode->hsync_end > panel_fixed_mode->htotal)
 112                 panel_fixed_mode->htotal = panel_fixed_mode->hsync_end + 1;
 113         if (panel_fixed_mode->vsync_end > panel_fixed_mode->vtotal)
 114                 panel_fixed_mode->vtotal = panel_fixed_mode->vsync_end + 1;
 115
 116         drm_mode_set_name(panel_fixed_mode);
 117 }
 118
 119 static bool
 120 lvds_dvo_timing_equal_size(const struct lvds_dvo_timing *a,
 121                            const struct lvds_dvo_timing *b)
 122 {
 123         if (a->hactive_hi != b->hactive_hi ||
 124             a->hactive_lo != b->hactive_lo)
 125                 return false;
 126
 127         if (a->hsync_off_hi != b->hsync_off_hi ||
 128             a->hsync_off_lo != b->hsync_off_lo)
 129                 return false;
 130
 131         if (a->hsync_pulse_width != b->hsync_pulse_width)
 132                 return false;
 133
 134         if (a->hblank_hi != b->hblank_hi ||
 135             a->hblank_lo != b->hblank_lo)
 136                 return false;
 137
 138         if (a->vactive_hi != b->vactive_hi ||
 139             a->vactive_lo != b->vactive_lo)
 140                 return false;
 141
 142         if (a->vsync_off != b->vsync_off)
 143                 return false;
 144
 145         if (a->vsync_pulse_width != b->vsync_pulse_width)
 146                 return false;
 147
 148         if (a->vblank_hi != b->vblank_hi ||
 149             a->vblank_lo != b->vblank_lo)
 150                 return false;
 151
 152         return true;
 153 }
 154
 155 static const struct lvds_dvo_timing *
 156 get_lvds_dvo_timing(const struct bdb_lvds_lfp_data *lvds_lfp_data,
 157                     const struct bdb_lvds_lfp_data_ptrs *lvds_lfp_data_ptrs,
 158                     int index)
 159 {
 160         /*
 161          * the size of fp_timing varies on the different platform.
 162          * So calculate the DVO timing relative offset in LVDS data
 163          * entry to get the DVO timing entry
 164          */
 165
 166         int lfp_data_size =
 167                 lvds_lfp_data_ptrs->ptr[1].dvo_timing_offset -
 168                 lvds_lfp_data_ptrs->ptr[0].dvo_timing_offset;
 169         int dvo_timing_offset =
 170                 lvds_lfp_data_ptrs->ptr[0].dvo_timing_offset -
 171                 lvds_lfp_data_ptrs->ptr[0].fp_timing_offset;
 172         char *entry = (char *)lvds_lfp_data->data + lfp_data_size * index;
 173
 174         return (struct lvds_dvo_timing *)(entry + dvo_timing_offset);
 175 }
 176
 177 /* Try to find integrated panel data */
 178 static void
 179 parse_lfp_panel_data(struct drm_i915_private *dev_priv,
 180                             struct bdb_header *bdb)
 181 {
 182         const struct bdb_lvds_options *lvds_options;
 183         const struct bdb_lvds_lfp_data *lvds_lfp_data;
 184         const struct bdb_lvds_lfp_data_ptrs *lvds_lfp_data_ptrs;
 185         const struct lvds_dvo_timing *panel_dvo_timing;
 186         struct drm_display_mode *panel_fixed_mode;
 187         int i, downclock;
 188
 189         lvds_options = find_section(bdb, BDB_LVDS_OPTIONS);
 190         if (!lvds_options)
 191                 return;
 192
 193         dev_priv->lvds_dither = lvds_options->pixel_dither;
 194         if (lvds_options->panel_type == 0xff)
 195                 return;
 196
 197         panel_type = lvds_options->panel_type;
 198
 199         lvds_lfp_data = find_section(bdb, BDB_LVDS_LFP_DATA);
 200         if (!lvds_lfp_data)
 201                 return;
 202
 203         lvds_lfp_data_ptrs = find_section(bdb, BDB_LVDS_LFP_DATA_PTRS);
 204         if (!lvds_lfp_data_ptrs)
 205                 return;
 206
 207         dev_priv->lvds_vbt = 1;
 208
 209         panel_dvo_timing = get_lvds_dvo_timing(lvds_lfp_data,
 210                                                lvds_lfp_data_ptrs,
 211                                                lvds_options->panel_type);
 212
 213         panel_fixed_mode = kzalloc(sizeof(*panel_fixed_mode), GFP_KERNEL);
 214         if (!panel_fixed_mode)
 215                 return;
 216
 217         fill_detail_timing_data(panel_fixed_mode, panel_dvo_timing);
 218
 219         dev_priv->lfp_lvds_vbt_mode = panel_fixed_mode;
 220
 221         DRM_DEBUG_KMS("Found panel mode in BIOS VBT tables:\n");
 222         drm_mode_debug_printmodeline(panel_fixed_mode);
 223
 224         /*
 225          * Iterate over the LVDS panel timing info to find the lowest clock
 226          * for the native resolution.
 227          */
 228         downclock = panel_dvo_timing->clock;
 229         for (i = 0; i < 16; i++) {
 230                 const struct lvds_dvo_timing *dvo_timing;
 231
 232                 dvo_timing = get_lvds_dvo_timing(lvds_lfp_data,
 233                                                  lvds_lfp_data_ptrs,
 234                                                  i);
 235                 if (lvds_dvo_timing_equal_size(dvo_timing, panel_dvo_timing) &&
 236                     dvo_timing->clock < downclock)
 237                         downclock = dvo_timing->clock;
 238         }
 239
 240         if (downclock < panel_dvo_timing->clock && i915_lvds_downclock) {
 241                 dev_priv->lvds_downclock_avail = 1;
 242                 dev_priv->lvds_downclock = downclock * 10;
 243                 DRM_DEBUG_KMS("LVDS downclock is found in VBT. "
 244                               "Normal Clock %dKHz, downclock %dKHz\n",
 245                               panel_fixed_mode->clock, 10*downclock);
 246         }
 247 }
 248
 249 /* Try to find sdvo panel data */
 250 static void
 251 parse_sdvo_panel_data(struct drm_i915_private *dev_priv,
 252                       struct bdb_header *bdb)
 253 {
 254         struct lvds_dvo_timing *dvo_timing;
 255         struct drm_display_mode *panel_fixed_mode;
 256         int index;
 257
 258         index = i915_vbt_sdvo_panel_type;
 259         if (index == -1) {
 260                 struct bdb_sdvo_lvds_options *sdvo_lvds_options;
 261
 262                 sdvo_lvds_options = find_section(bdb, BDB_SDVO_LVDS_OPTIONS);
 263                 if (!sdvo_lvds_options)
 264                         return;
 265
 266                 index = sdvo_lvds_options->panel_type;
 267         }
 268
 269         dvo_timing = find_section(bdb, BDB_SDVO_PANEL_DTDS);
 270         if (!dvo_timing)
 271                 return;
 272
 273         panel_fixed_mode = kzalloc(sizeof(*panel_fixed_mode), GFP_KERNEL);
 274         if (!panel_fixed_mode)
 275                 return;
 276
 277         fill_detail_timing_data(panel_fixed_mode, dvo_timing + index);
 278
 279         dev_priv->sdvo_lvds_vbt_mode = panel_fixed_mode;
 280
 281         DRM_DEBUG_KMS("Found SDVO panel mode in BIOS VBT tables:\n");
 282         drm_mode_debug_printmodeline(panel_fixed_mode);
 283 }
 284
 285 static int intel_bios_ssc_frequency(struct drm_device *dev,
 286                                     bool alternate)
 287 {
 288         switch (INTEL_INFO(dev)->gen) {
 289         case 2:
 290                 return alternate ? 66 : 48;
 291         case 3:
 292         case 4:
 293                 return alternate ? 100 : 96;
 294         default:
 295                 return alternate ? 100 : 120;
 296         }
 297 }
 298
 299 static void
 300 parse_general_features(struct drm_i915_private *dev_priv,
 301                        struct bdb_header *bdb)
 302 {
 303         struct drm_device *dev = dev_priv->dev;
 304         struct bdb_general_features *general;
 305
 306         general = find_section(bdb, BDB_GENERAL_FEATURES);
 307         if (general) {
 308                 dev_priv->int_tv_support = general->int_tv_support;
 309                 dev_priv->int_crt_support = general->int_crt_support;
 310                 dev_priv->lvds_use_ssc = general->enable_ssc;
 311                 dev_priv->lvds_ssc_freq =
 312                         intel_bios_ssc_frequency(dev, general->ssc_freq);
 313                 dev_priv->display_clock_mode = general->display_clock_mode;
 314                 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\n",
 315                               dev_priv->int_tv_support,
 316                               dev_priv->int_crt_support,
 317                               dev_priv->lvds_use_ssc,
 318                               dev_priv->lvds_ssc_freq,
 319                               dev_priv->display_clock_mode);
 320         }
 321 }
 322
 323 static void
 324 parse_general_definitions(struct drm_i915_private *dev_priv,
 325                           struct bdb_header *bdb)
 326 {
 327         struct bdb_general_definitions *general;
 328
 329         general = find_section(bdb, BDB_GENERAL_DEFINITIONS);
 330         if (general) {
 331                 u16 block_size = get_blocksize(general);
 332                 if (block_size >= sizeof(*general)) {
 333                         int bus_pin = general->crt_ddc_gmbus_pin;
 334                         DRM_DEBUG_KMS("crt_ddc_bus_pin: %d\n", bus_pin);
 335                         if (bus_pin >= 1 && bus_pin <= 6)
 336                                 dev_priv->crt_ddc_pin = bus_pin;
 337                 } else {
 338                         DRM_DEBUG_KMS("BDB_GD too small (%d). Invalid.\n",
 339                                   block_size);
 340                 }
 341         }
 342 }
 343
 344 static void
 345 parse_sdvo_device_mapping(struct drm_i915_private *dev_priv,
 346                           struct bdb_header *bdb)
 347 {
 348         struct sdvo_device_mapping *p_mapping;
 349         struct bdb_general_definitions *p_defs;
 350         struct child_device_config *p_child;
 351         int i, child_device_num, count;
 352         u16     block_size;
 353
 354         p_defs = find_section(bdb, BDB_GENERAL_DEFINITIONS);
 355         if (!p_defs) {
 356                 DRM_DEBUG_KMS("No general definition block is found, unable to construct sdvo mapping.\n");
 357                 return;
 358         }
 359         /* judge whether the size of child device meets the requirements.
 360          * If the child device size obtained from general definition block
 361          * is different with sizeof(struct child_device_config), skip the
 362          * parsing of sdvo device info
 363          */
 364         if (p_defs->child_dev_size != sizeof(*p_child)) {
 365                 /* different child dev size . Ignore it */
 366                 DRM_DEBUG_KMS("different child size is found. Invalid.\n");
 367                 return;
 368         }
 369         /* get the block size of general definitions */
 370         block_size = get_blocksize(p_defs);
 371         /* get the number of child device */
 372         child_device_num = (block_size - sizeof(*p_defs)) /
 373                                 sizeof(*p_child);
 374         count = 0;
 375         for (i = 0; i < child_device_num; i++) {
 376                 p_child = &(p_defs->devices[i]);
 377                 if (!p_child->device_type) {
 378                         /* skip the device block if device type is invalid */
 379                         continue;
 380                 }
 381                 if (p_child->slave_addr != SLAVE_ADDR1 &&
 382                         p_child->slave_addr != SLAVE_ADDR2) {
 383                         /*
 384                          * If the slave address is neither 0x70 nor 0x72,
 385                          * it is not a SDVO device. Skip it.
 386                          */
 387                         continue;
 388                 }
 389                 if (p_child->dvo_port != DEVICE_PORT_DVOB &&
 390                         p_child->dvo_port != DEVICE_PORT_DVOC) {
 391                         /* skip the incorrect SDVO port */
 392                         DRM_DEBUG_KMS("Incorrect SDVO port. Skip it\n");
 393                         continue;
 394                 }
 395                 DRM_DEBUG_KMS("the SDVO device with slave addr %2x is found on"
 396                                 " %s port\n",
 397                                 p_child->slave_addr,
 398                                 (p_child->dvo_port == DEVICE_PORT_DVOB) ?
 399                                         "SDVOB" : "SDVOC");
 400                 p_mapping = &(dev_priv->sdvo_mappings[p_child->dvo_port - 1]);
 401                 if (!p_mapping->initialized) {
 402                         p_mapping->dvo_port = p_child->dvo_port;
 403                         p_mapping->slave_addr = p_child->slave_addr;
 404                         p_mapping->dvo_wiring = p_child->dvo_wiring;
 405                         p_mapping->ddc_pin = p_child->ddc_pin;
 406                         p_mapping->i2c_pin = p_child->i2c_pin;
 407                         p_mapping->initialized = 1;
 408                         DRM_DEBUG_KMS("SDVO device: dvo=%x, addr=%x, wiring=%d, ddc_pin=%d, i2c_pin=%d\n",
 409                                       p_mapping->dvo_port,
 410                                       p_mapping->slave_addr,
 411                                       p_mapping->dvo_wiring,
 412                                       p_mapping->ddc_pin,
 413                                       p_mapping->i2c_pin);
 414                 } else {
 415                         DRM_DEBUG_KMS("Maybe one SDVO port is shared by "
 416                                          "two SDVO device.\n");
 417                 }
 418                 if (p_child->slave2_addr) {
 419                         /* Maybe this is a SDVO device with multiple inputs */
 420                         /* And the mapping info is not added */
 421                         DRM_DEBUG_KMS("there exists the slave2_addr. Maybe this"
 422                                 " is a SDVO device with multiple inputs.\n");
 423                 }
 424                 count++;
 425         }
 426
 427         if (!count) {
 428                 /* No SDVO device info is found */
 429                 DRM_DEBUG_KMS("No SDVO device info is found in VBT\n");
 430         }
 431         return;
 432 }
 433
 434 static void
 435 parse_driver_features(struct drm_i915_private *dev_priv,
 436                        struct bdb_header *bdb)
 437 {
 438         struct drm_device *dev = dev_priv->dev;
 439         struct bdb_driver_features *driver;
 440
 441         driver = find_section(bdb, BDB_DRIVER_FEATURES);
 442         if (!driver)
 443                 return;
 444
 445         if (SUPPORTS_EDP(dev) &&
 446             driver->lvds_config == BDB_DRIVER_FEATURE_EDP)
 447                 dev_priv->edp.support = 1;
 448
 449         if (driver->dual_frequency)
 450                 dev_priv->render_reclock_avail = true;
 451 }
 452
 453 static void
 454 parse_edp(struct drm_i915_private *dev_priv, struct bdb_header *bdb)
 455 {
 456         struct bdb_edp *edp;
 457         struct edp_power_seq *edp_pps;
 458         struct edp_link_params *edp_link_params;
 459
 460         edp = find_section(bdb, BDB_EDP);
 461         if (!edp) {
 462                 if (SUPPORTS_EDP(dev_priv->dev) && dev_priv->edp.support) {
 463                         DRM_DEBUG_KMS("No eDP BDB found but eDP panel "
 464                                       "supported, assume %dbpp panel color "
 465                                       "depth.\n",
 466                                       dev_priv->edp.bpp);
 467                 }
 468                 return;
 469         }
 470
 471         switch ((edp->color_depth >> (panel_type * 2)) & 3) {
 472         case EDP_18BPP:
 473                 dev_priv->edp.bpp = 18;
 474                 break;
 475         case EDP_24BPP:
 476                 dev_priv->edp.bpp = 24;
 477                 break;
 478         case EDP_30BPP:
 479                 dev_priv->edp.bpp = 30;
 480                 break;
 481         }
 482
 483         /* Get the eDP sequencing and link info */
 484         edp_pps = &edp->power_seqs[panel_type];
 485         edp_link_params = &edp->link_params[panel_type];
 486
 487         dev_priv->edp.pps = *edp_pps;
 488
 489         dev_priv->edp.rate = edp_link_params->rate ? DP_LINK_BW_2_7 :
 490                 DP_LINK_BW_1_62;
 491         switch (edp_link_params->lanes) {
 492         case 0:
 493                 dev_priv->edp.lanes = 1;
 494                 break;
 495         case 1:
 496                 dev_priv->edp.lanes = 2;
 497                 break;
 498         case 3:
 499         default:
 500                 dev_priv->edp.lanes = 4;
 501                 break;
 502         }
 503         switch (edp_link_params->preemphasis) {
 504         case 0:
 505                 dev_priv->edp.preemphasis = DP_TRAIN_PRE_EMPHASIS_0;
 506                 break;
 507         case 1:
 508                 dev_priv->edp.preemphasis = DP_TRAIN_PRE_EMPHASIS_3_5;
 509                 break;
 510         case 2:
 511                 dev_priv->edp.preemphasis = DP_TRAIN_PRE_EMPHASIS_6;
 512                 break;
 513         case 3:
 514                 dev_priv->edp.preemphasis = DP_TRAIN_PRE_EMPHASIS_9_5;
 515                 break;
 516         }
 517         switch (edp_link_params->vswing) {
 518         case 0:
 519                 dev_priv->edp.vswing = DP_TRAIN_VOLTAGE_SWING_400;
 520                 break;
 521         case 1:
 522                 dev_priv->edp.vswing = DP_TRAIN_VOLTAGE_SWING_600;
 523                 break;
 524         case 2:
 525                 dev_priv->edp.vswing = DP_TRAIN_VOLTAGE_SWING_800;
 526                 break;
 527         case 3:
 528                 dev_priv->edp.vswing = DP_TRAIN_VOLTAGE_SWING_1200;
 529                 break;
 530         }
 531 }
 532
 533 static void
 534 parse_device_mapping(struct drm_i915_private *dev_priv,
 535                        struct bdb_header *bdb)
 536 {
 537         struct bdb_general_definitions *p_defs;
 538         struct child_device_config *p_child, *child_dev_ptr;
 539         int i, child_device_num, count;
 540         u16     block_size;
 541
 542         p_defs = find_section(bdb, BDB_GENERAL_DEFINITIONS);
 543         if (!p_defs) {
 544                 DRM_DEBUG_KMS("No general definition block is found, no devices defined.\n");
 545                 return;
 546         }
 547         /* judge whether the size of child device meets the requirements.
 548          * If the child device size obtained from general definition block
 549          * is different with sizeof(struct child_device_config), skip the
 550          * parsing of sdvo device info
 551          */
 552         if (p_defs->child_dev_size != sizeof(*p_child)) {
 553                 /* different child dev size . Ignore it */
 554                 DRM_DEBUG_KMS("different child size is found. Invalid.\n");
 555                 return;
 556         }
 557         /* get the block size of general definitions */
 558         block_size = get_blocksize(p_defs);
 559         /* get the number of child device */
 560         child_device_num = (block_size - sizeof(*p_defs)) /
 561                                 sizeof(*p_child);
 562         count = 0;
 563         /* get the number of child device that is present */
 564         for (i = 0; i < child_device_num; i++) {
 565                 p_child = &(p_defs->devices[i]);
 566                 if (!p_child->device_type) {
 567                         /* skip the device block if device type is invalid */
 568                         continue;
 569                 }
 570                 count++;
 571         }
 572         if (!count) {
 573                 DRM_DEBUG_KMS("no child dev is parsed from VBT\n");
 574                 return;
 575         }
 576         dev_priv->child_dev = kzalloc(sizeof(*p_child) * count, GFP_KERNEL);
 577         if (!dev_priv->child_dev) {
 578                 DRM_DEBUG_KMS("No memory space for child device\n");
 579                 return;
 580         }
 581
 582         dev_priv->child_dev_num = count;
 583         count = 0;
 584         for (i = 0; i < child_device_num; i++) {
 585                 p_child = &(p_defs->devices[i]);
 586                 if (!p_child->device_type) {
 587                         /* skip the device block if device type is invalid */
 588                         continue;
 589                 }
 590                 child_dev_ptr = dev_priv->child_dev + count;
 591                 count++;
 592                 memcpy((void *)child_dev_ptr, (void *)p_child,
 593                                         sizeof(*p_child));
 594         }
 595         return;
 596 }
 597
 598 static void
 599 init_vbt_defaults(struct drm_i915_private *dev_priv)
 600 {
 601         struct drm_device *dev = dev_priv->dev;
 602
 603         dev_priv->crt_ddc_pin = GMBUS_PORT_VGADDC;
 604
 605         /* LFP panel data */
 606         dev_priv->lvds_dither = 1;
 607         dev_priv->lvds_vbt = 0;
 608
 609         /* SDVO panel data */
 610         dev_priv->sdvo_lvds_vbt_mode = NULL;
 611
 612         /* general features */
 613         dev_priv->int_tv_support = 1;
 614         dev_priv->int_crt_support = 1;
 615
 616         /* Default to using SSC */
 617         dev_priv->lvds_use_ssc = 1;
 618         dev_priv->lvds_ssc_freq = intel_bios_ssc_frequency(dev, 1);
 619         DRM_DEBUG_KMS("Set default to SSC at %dMHz\n", dev_priv->lvds_ssc_freq);
 620
 621         /* eDP data */
 622         dev_priv->edp.bpp = 18;
 623 }
 624
 625 static int __init intel_no_opregion_vbt_callback(const struct dmi_system_id *id)
 626 {
 627         DRM_DEBUG_KMS("Falling back to manually reading VBT from "
 628                       "VBIOS ROM for %s\n",
 629                       id->ident);
 630         return 1;
 631 }
 632
 633 static const struct dmi_system_id intel_no_opregion_vbt[] = {
 634         {
 635                 .callback = intel_no_opregion_vbt_callback,
 636                 .ident = "ThinkCentre A57",
 637                 .matches = {
 638                         DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
 639                         DMI_MATCH(DMI_PRODUCT_NAME, "97027RG"),
 640                 },
 641         },
 642         { }
 643 };
 644
 645 /**
 646  * intel_parse_bios - find VBT and initialize settings from the BIOS
 647  * @dev: DRM device
 648  *
 649  * Loads the Video BIOS and checks that the VBT exists.  Sets scratch registers
 650  * to appropriate values.
 651  *
 652  * Returns 0 on success, nonzero on failure.
 653  */
 654 bool
 655 intel_parse_bios(struct drm_device *dev)
 656 {
 657         struct drm_i915_private *dev_priv = dev->dev_private;
 658         struct pci_dev *pdev = dev->pdev;
 659         struct bdb_header *bdb = NULL;
 660         u8 __iomem *bios = NULL;
 661
 662         init_vbt_defaults(dev_priv);
 663
 664         /* XXX Should this validation be moved to intel_opregion.c? */
 665         if (!dmi_check_system(intel_no_opregion_vbt) && dev_priv->opregion.vbt) {
 666                 struct vbt_header *vbt = dev_priv->opregion.vbt;
 667                 if (memcmp(vbt->signature, "$VBT", 4) == 0) {
 668                         DRM_DEBUG_KMS("Using VBT from OpRegion: %20s\n",
 669                                          vbt->signature);
 670                         bdb = (struct bdb_header *)((char *)vbt + vbt->bdb_offset);
 671                 } else
 672                         dev_priv->opregion.vbt = NULL;
 673         }
 674
 675         if (bdb == NULL) {
 676                 struct vbt_header *vbt = NULL;
 677                 size_t size;
 678                 int i;
 679
 680                 bios = pci_map_rom(pdev, &size);
 681                 if (!bios)
 682                         return -1;
 683
 684                 /* Scour memory looking for the VBT signature */
 685                 for (i = 0; i + 4 < size; i++) {
 686                         if (!memcmp(bios + i, "$VBT", 4)) {
 687                                 vbt = (struct vbt_header *)(bios + i);
 688                                 break;
 689                         }
 690                 }
 691
 692                 if (!vbt) {
 693                         DRM_ERROR("VBT signature missing\n");
 694                         pci_unmap_rom(pdev, bios);
 695                         return -1;
 696                 }
 697
 698                 bdb = (struct bdb_header *)(bios + i + vbt->bdb_offset);
 699         }
 700
 701         /* Grab useful general definitions */
 702         parse_general_features(dev_priv, bdb);
 703         parse_general_definitions(dev_priv, bdb);
 704         parse_lfp_panel_data(dev_priv, bdb);
 705         parse_sdvo_panel_data(dev_priv, bdb);
 706         parse_sdvo_device_mapping(dev_priv, bdb);
 707         parse_device_mapping(dev_priv, bdb);
 708         parse_driver_features(dev_priv, bdb);
 709         parse_edp(dev_priv, bdb);
 710
 711         if (bios)
 712                 pci_unmap_rom(pdev, bios);
 713
 714         return 0;
 715 }
 716
 717 /* Ensure that vital registers have been initialised, even if the BIOS
 718  * is absent or just failing to do its job.
 719  */
 720 void intel_setup_bios(struct drm_device *dev)
 721 {
 722         struct drm_i915_private *dev_priv = dev->dev_private;
 723
 724          /* Set the Panel Power On/Off timings if uninitialized. */
 725         if ((I915_READ(PP_ON_DELAYS) == 0) && (I915_READ(PP_OFF_DELAYS) == 0)) {
 726                 /* Set T2 to 40ms and T5 to 200ms */
 727                 I915_WRITE(PP_ON_DELAYS, 0x019007d0);
 728
 729                 /* Set T3 to 35ms and Tx to 200ms */
 730                 I915_WRITE(PP_OFF_DELAYS, 0x015e07d0);
 731         }
 732 }