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 <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
  37 static int panel_type;
  38
  39 static void *
  40 find_section(struct bdb_header *bdb, int section_id)
  41 {
  42         u8 *base = (u8 *)bdb;
  43         int index = 0;
  44         u16 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 < total) {
  53                 current_id = *(base + index);
  54                 index++;
  55                 current_size = *((u16 *)(base + index));
  56                 index += 2;
  57                 if (current_id == section_id)
  58                         return base + index;
  59                 index += current_size;
  60         }
  61
  62         return NULL;
  63 }
  64
  65 static u16
  66 get_blocksize(void *p)
  67 {
  68         u16 *block_ptr, block_size;
  69
  70         block_ptr = (u16 *)((char *)p - 2);
  71         block_size = *block_ptr;
  72         return block_size;
  73 }
  74
  75 static void
  76 fill_detail_timing_data(struct drm_display_mode *panel_fixed_mode,
  77                         const struct lvds_dvo_timing *dvo_timing)
  78 {
  79         panel_fixed_mode->hdisplay = (dvo_timing->hactive_hi << 8) |
  80                 dvo_timing->hactive_lo;
  81         panel_fixed_mode->hsync_start = panel_fixed_mode->hdisplay +
  82                 ((dvo_timing->hsync_off_hi << 8) | dvo_timing->hsync_off_lo);
  83         panel_fixed_mode->hsync_end = panel_fixed_mode->hsync_start +
  84                 dvo_timing->hsync_pulse_width;
  85         panel_fixed_mode->htotal = panel_fixed_mode->hdisplay +
  86                 ((dvo_timing->hblank_hi << 8) | dvo_timing->hblank_lo);
  87
  88         panel_fixed_mode->vdisplay = (dvo_timing->vactive_hi << 8) |
  89                 dvo_timing->vactive_lo;
  90         panel_fixed_mode->vsync_start = panel_fixed_mode->vdisplay +
  91                 dvo_timing->vsync_off;
  92         panel_fixed_mode->vsync_end = panel_fixed_mode->vsync_start +
  93                 dvo_timing->vsync_pulse_width;
  94         panel_fixed_mode->vtotal = panel_fixed_mode->vdisplay +
  95                 ((dvo_timing->vblank_hi << 8) | dvo_timing->vblank_lo);
  96         panel_fixed_mode->clock = dvo_timing->clock * 10;
  97         panel_fixed_mode->type = DRM_MODE_TYPE_PREFERRED;
  98
  99         if (dvo_timing->hsync_positive)
 100                 panel_fixed_mode->flags |= DRM_MODE_FLAG_PHSYNC;
 101         else
 102                 panel_fixed_mode->flags |= DRM_MODE_FLAG_NHSYNC;
 103
 104         if (dvo_timing->vsync_positive)
 105                 panel_fixed_mode->flags |= DRM_MODE_FLAG_PVSYNC;
 106         else
 107                 panel_fixed_mode->flags |= DRM_MODE_FLAG_NVSYNC;
 108
 109         /* Some VBTs have bogus h/vtotal values */
 110         if (panel_fixed_mode->hsync_end > panel_fixed_mode->htotal)
 111                 panel_fixed_mode->htotal = panel_fixed_mode->hsync_end + 1;
 112         if (panel_fixed_mode->vsync_end > panel_fixed_mode->vtotal)
 113                 panel_fixed_mode->vtotal = panel_fixed_mode->vsync_end + 1;
 114
 115         drm_mode_set_name(panel_fixed_mode);
 116 }
 117
 118 static bool
 119 lvds_dvo_timing_equal_size(const struct lvds_dvo_timing *a,
 120                            const struct lvds_dvo_timing *b)
 121 {
 122         if (a->hactive_hi != b->hactive_hi ||
 123             a->hactive_lo != b->hactive_lo)
 124                 return false;
 125
 126         if (a->hsync_off_hi != b->hsync_off_hi ||
 127             a->hsync_off_lo != b->hsync_off_lo)
 128                 return false;
 129
 130         if (a->hsync_pulse_width != b->hsync_pulse_width)
 131                 return false;
 132
 133         if (a->hblank_hi != b->hblank_hi ||
 134             a->hblank_lo != b->hblank_lo)
 135                 return false;
 136
 137         if (a->vactive_hi != b->vactive_hi ||
 138             a->vactive_lo != b->vactive_lo)
 139                 return false;
 140
 141         if (a->vsync_off != b->vsync_off)
 142                 return false;
 143
 144         if (a->vsync_pulse_width != b->vsync_pulse_width)
 145                 return false;
 146
 147         if (a->vblank_hi != b->vblank_hi ||
 148             a->vblank_lo != b->vblank_lo)
 149                 return false;
 150
 151         return true;
 152 }
 153
 154 static const struct lvds_dvo_timing *
 155 get_lvds_dvo_timing(const struct bdb_lvds_lfp_data *lvds_lfp_data,
 156                     const struct bdb_lvds_lfp_data_ptrs *lvds_lfp_data_ptrs,
 157                     int index)
 158 {
 159         /*
 160          * the size of fp_timing varies on the different platform.
 161          * So calculate the DVO timing relative offset in LVDS data
 162          * entry to get the DVO timing entry
 163          */
 164
 165         int lfp_data_size =
 166                 lvds_lfp_data_ptrs->ptr[1].dvo_timing_offset -
 167                 lvds_lfp_data_ptrs->ptr[0].dvo_timing_offset;
 168         int dvo_timing_offset =
 169                 lvds_lfp_data_ptrs->ptr[0].dvo_timing_offset -
 170                 lvds_lfp_data_ptrs->ptr[0].fp_timing_offset;
 171         char *entry = (char *)lvds_lfp_data->data + lfp_data_size * index;
 172
 173         return (struct lvds_dvo_timing *)(entry + dvo_timing_offset);
 174 }
 175
 176 /* get lvds_fp_timing entry
 177  * this function may return NULL if the corresponding entry is invalid
 178  */
 179 static const struct lvds_fp_timing *
 180 get_lvds_fp_timing(const struct bdb_header *bdb,
 181                    const struct bdb_lvds_lfp_data *data,
 182                    const struct bdb_lvds_lfp_data_ptrs *ptrs,
 183                    int index)
 184 {
 185         size_t data_ofs = (const u8 *)data - (const u8 *)bdb;
 186         u16 data_size = ((const u16 *)data)[-1]; /* stored in header */
 187         size_t ofs;
 188
 189         if (index >= ARRAY_SIZE(ptrs->ptr))
 190                 return NULL;
 191         ofs = ptrs->ptr[index].fp_timing_offset;
 192         if (ofs < data_ofs ||
 193             ofs + sizeof(struct lvds_fp_timing) > data_ofs + data_size)
 194                 return NULL;
 195         return (const struct lvds_fp_timing *)((const u8 *)bdb + ofs);
 196 }
 197
 198 /* Try to find integrated panel data */
 199 static void
 200 parse_lfp_panel_data(struct drm_i915_private *dev_priv,
 201                             struct bdb_header *bdb)
 202 {
 203         const struct bdb_lvds_options *lvds_options;
 204         const struct bdb_lvds_lfp_data *lvds_lfp_data;
 205         const struct bdb_lvds_lfp_data_ptrs *lvds_lfp_data_ptrs;
 206         const struct lvds_dvo_timing *panel_dvo_timing;
 207         const struct lvds_fp_timing *fp_timing;
 208         struct drm_display_mode *panel_fixed_mode;
 209         int i, downclock;
 210
 211         lvds_options = find_section(bdb, BDB_LVDS_OPTIONS);
 212         if (!lvds_options)
 213                 return;
 214
 215         dev_priv->lvds_dither = lvds_options->pixel_dither;
 216         if (lvds_options->panel_type == 0xff)
 217                 return;
 218
 219         panel_type = lvds_options->panel_type;
 220
 221         lvds_lfp_data = find_section(bdb, BDB_LVDS_LFP_DATA);
 222         if (!lvds_lfp_data)
 223                 return;
 224
 225         lvds_lfp_data_ptrs = find_section(bdb, BDB_LVDS_LFP_DATA_PTRS);
 226         if (!lvds_lfp_data_ptrs)
 227                 return;
 228
 229         dev_priv->lvds_vbt = 1;
 230
 231         panel_dvo_timing = get_lvds_dvo_timing(lvds_lfp_data,
 232                                                lvds_lfp_data_ptrs,
 233                                                lvds_options->panel_type);
 234
 235         panel_fixed_mode = kzalloc(sizeof(*panel_fixed_mode), GFP_KERNEL);
 236         if (!panel_fixed_mode)
 237                 return;
 238
 239         fill_detail_timing_data(panel_fixed_mode, panel_dvo_timing);
 240
 241         dev_priv->lfp_lvds_vbt_mode = panel_fixed_mode;
 242
 243         DRM_DEBUG_KMS("Found panel mode in BIOS VBT tables:\n");
 244         drm_mode_debug_printmodeline(panel_fixed_mode);
 245
 246         /*
 247          * Iterate over the LVDS panel timing info to find the lowest clock
 248          * for the native resolution.
 249          */
 250         downclock = panel_dvo_timing->clock;
 251         for (i = 0; i < 16; i++) {
 252                 const struct lvds_dvo_timing *dvo_timing;
 253
 254                 dvo_timing = get_lvds_dvo_timing(lvds_lfp_data,
 255                                                  lvds_lfp_data_ptrs,
 256                                                  i);
 257                 if (lvds_dvo_timing_equal_size(dvo_timing, panel_dvo_timing) &&
 258                     dvo_timing->clock < downclock)
 259                         downclock = dvo_timing->clock;
 260         }
 261
 262         if (downclock < panel_dvo_timing->clock && i915_lvds_downclock) {
 263                 dev_priv->lvds_downclock_avail = 1;
 264                 dev_priv->lvds_downclock = downclock * 10;
 265                 DRM_DEBUG_KMS("LVDS downclock is found in VBT. "
 266                               "Normal Clock %dKHz, downclock %dKHz\n",
 267                               panel_fixed_mode->clock, 10*downclock);
 268         }
 269
 270         fp_timing = get_lvds_fp_timing(bdb, lvds_lfp_data,
 271                                        lvds_lfp_data_ptrs,
 272                                        lvds_options->panel_type);
 273         if (fp_timing) {
 274                 /* check the resolution, just to be sure */
 275                 if (fp_timing->x_res == panel_fixed_mode->hdisplay &&
 276                     fp_timing->y_res == panel_fixed_mode->vdisplay) {
 277                         dev_priv->bios_lvds_val = fp_timing->lvds_reg_val;
 278                         DRM_DEBUG_KMS("VBT initial LVDS value %x\n",
 279                                       dev_priv->bios_lvds_val);
 280                 }
 281         }
 282 }
 283
 284 /* Try to find sdvo panel data */
 285 static void
 286 parse_sdvo_panel_data(struct drm_i915_private *dev_priv,
 287                       struct bdb_header *bdb)
 288 {
 289         struct lvds_dvo_timing *dvo_timing;
 290         struct drm_display_mode *panel_fixed_mode;
 291         int index;
 292
 293         index = i915_vbt_sdvo_panel_type;
 294         if (index == -2) {
 295                 DRM_DEBUG_KMS("Ignore SDVO panel mode from BIOS VBT tables.\n");
 296                 return;
 297         }
 298
 299         if (index == -1) {
 300                 struct bdb_sdvo_lvds_options *sdvo_lvds_options;
 301
 302                 sdvo_lvds_options = find_section(bdb, BDB_SDVO_LVDS_OPTIONS);
 303                 if (!sdvo_lvds_options)
 304                         return;
 305
 306                 index = sdvo_lvds_options->panel_type;
 307         }
 308
 309         dvo_timing = find_section(bdb, BDB_SDVO_PANEL_DTDS);
 310         if (!dvo_timing)
 311                 return;
 312
 313         panel_fixed_mode = kzalloc(sizeof(*panel_fixed_mode), GFP_KERNEL);
 314         if (!panel_fixed_mode)
 315                 return;
 316
 317         fill_detail_timing_data(panel_fixed_mode, dvo_timing + index);
 318
 319         dev_priv->sdvo_lvds_vbt_mode = panel_fixed_mode;
 320
 321         DRM_DEBUG_KMS("Found SDVO panel mode in BIOS VBT tables:\n");
 322         drm_mode_debug_printmodeline(panel_fixed_mode);
 323 }
 324
 325 static int intel_bios_ssc_frequency(struct drm_device *dev,
 326                                     bool alternate)
 327 {
 328         switch (INTEL_INFO(dev)->gen) {
 329         case 2:
 330                 return alternate ? 66 : 48;
 331         case 3:
 332         case 4:
 333                 return alternate ? 100 : 96;
 334         default:
 335                 return alternate ? 100 : 120;
 336         }
 337 }
 338
 339 static void
 340 parse_general_features(struct drm_i915_private *dev_priv,
 341                        struct bdb_header *bdb)
 342 {
 343         struct drm_device *dev = dev_priv->dev;
 344         struct bdb_general_features *general;
 345
 346         general = find_section(bdb, BDB_GENERAL_FEATURES);
 347         if (general) {
 348                 dev_priv->int_tv_support = general->int_tv_support;
 349                 dev_priv->int_crt_support = general->int_crt_support;
 350                 dev_priv->lvds_use_ssc = general->enable_ssc;
 351                 dev_priv->lvds_ssc_freq =
 352                         intel_bios_ssc_frequency(dev, general->ssc_freq);
 353                 dev_priv->display_clock_mode = general->display_clock_mode;
 354                 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",
 355                               dev_priv->int_tv_support,
 356                               dev_priv->int_crt_support,
 357                               dev_priv->lvds_use_ssc,
 358                               dev_priv->lvds_ssc_freq,
 359                               dev_priv->display_clock_mode);
 360         }
 361 }
 362
 363 static void
 364 parse_general_definitions(struct drm_i915_private *dev_priv,
 365                           struct bdb_header *bdb)
 366 {
 367         struct bdb_general_definitions *general;
 368
 369         general = find_section(bdb, BDB_GENERAL_DEFINITIONS);
 370         if (general) {
 371                 u16 block_size = get_blocksize(general);
 372                 if (block_size >= sizeof(*general)) {
 373                         int bus_pin = general->crt_ddc_gmbus_pin;
 374                         DRM_DEBUG_KMS("crt_ddc_bus_pin: %d\n", bus_pin);
 375                         if (intel_gmbus_is_port_valid(bus_pin))
 376                                 dev_priv->crt_ddc_pin = bus_pin;
 377                 } else {
 378                         DRM_DEBUG_KMS("BDB_GD too small (%d). Invalid.\n",
 379                                       block_size);
 380                 }
 381         }
 382 }
 383
 384 static void
 385 parse_sdvo_device_mapping(struct drm_i915_private *dev_priv,
 386                           struct bdb_header *bdb)
 387 {
 388         struct sdvo_device_mapping *p_mapping;
 389         struct bdb_general_definitions *p_defs;
 390         struct child_device_config *p_child;
 391         int i, child_device_num, count;
 392         u16     block_size;
 393
 394         p_defs = find_section(bdb, BDB_GENERAL_DEFINITIONS);
 395         if (!p_defs) {
 396                 DRM_DEBUG_KMS("No general definition block is found, unable to construct sdvo mapping.\n");
 397                 return;
 398         }
 399         /* judge whether the size of child device meets the requirements.
 400          * If the child device size obtained from general definition block
 401          * is different with sizeof(struct child_device_config), skip the
 402          * parsing of sdvo device info
 403          */
 404         if (p_defs->child_dev_size != sizeof(*p_child)) {
 405                 /* different child dev size . Ignore it */
 406                 DRM_DEBUG_KMS("different child size is found. Invalid.\n");
 407                 return;
 408         }
 409         /* get the block size of general definitions */
 410         block_size = get_blocksize(p_defs);
 411         /* get the number of child device */
 412         child_device_num = (block_size - sizeof(*p_defs)) /
 413                                 sizeof(*p_child);
 414         count = 0;
 415         for (i = 0; i < child_device_num; i++) {
 416                 p_child = &(p_defs->devices[i]);
 417                 if (!p_child->device_type) {
 418                         /* skip the device block if device type is invalid */
 419                         continue;
 420                 }
 421                 if (p_child->slave_addr != SLAVE_ADDR1 &&
 422                         p_child->slave_addr != SLAVE_ADDR2) {
 423                         /*
 424                          * If the slave address is neither 0x70 nor 0x72,
 425                          * it is not a SDVO device. Skip it.
 426                          */
 427                         continue;
 428                 }
 429                 if (p_child->dvo_port != DEVICE_PORT_DVOB &&
 430                         p_child->dvo_port != DEVICE_PORT_DVOC) {
 431                         /* skip the incorrect SDVO port */
 432                         DRM_DEBUG_KMS("Incorrect SDVO port. Skip it\n");
 433                         continue;
 434                 }
 435                 DRM_DEBUG_KMS("the SDVO device with slave addr %2x is found on"
 436                                 " %s port\n",
 437                                 p_child->slave_addr,
 438                                 (p_child->dvo_port == DEVICE_PORT_DVOB) ?
 439                                         "SDVOB" : "SDVOC");
 440                 p_mapping = &(dev_priv->sdvo_mappings[p_child->dvo_port - 1]);
 441                 if (!p_mapping->initialized) {
 442                         p_mapping->dvo_port = p_child->dvo_port;
 443                         p_mapping->slave_addr = p_child->slave_addr;
 444                         p_mapping->dvo_wiring = p_child->dvo_wiring;
 445                         p_mapping->ddc_pin = p_child->ddc_pin;
 446                         p_mapping->i2c_pin = p_child->i2c_pin;
 447                         p_mapping->initialized = 1;
 448                         DRM_DEBUG_KMS("SDVO device: dvo=%x, addr=%x, wiring=%d, ddc_pin=%d, i2c_pin=%d\n",
 449                                       p_mapping->dvo_port,
 450                                       p_mapping->slave_addr,
 451                                       p_mapping->dvo_wiring,
 452                                       p_mapping->ddc_pin,
 453                                       p_mapping->i2c_pin);
 454                 } else {
 455                         DRM_DEBUG_KMS("Maybe one SDVO port is shared by "
 456                                          "two SDVO device.\n");
 457                 }
 458                 if (p_child->slave2_addr) {
 459                         /* Maybe this is a SDVO device with multiple inputs */
 460                         /* And the mapping info is not added */
 461                         DRM_DEBUG_KMS("there exists the slave2_addr. Maybe this"
 462                                 " is a SDVO device with multiple inputs.\n");
 463                 }
 464                 count++;
 465         }
 466
 467         if (!count) {
 468                 /* No SDVO device info is found */
 469                 DRM_DEBUG_KMS("No SDVO device info is found in VBT\n");
 470         }
 471         return;
 472 }
 473
 474 static void
 475 parse_driver_features(struct drm_i915_private *dev_priv,
 476                        struct bdb_header *bdb)
 477 {
 478         struct drm_device *dev = dev_priv->dev;
 479         struct bdb_driver_features *driver;
 480
 481         driver = find_section(bdb, BDB_DRIVER_FEATURES);
 482         if (!driver)
 483                 return;
 484
 485         if (SUPPORTS_EDP(dev) &&
 486             driver->lvds_config == BDB_DRIVER_FEATURE_EDP)
 487                 dev_priv->edp.support = 1;
 488
 489         if (driver->dual_frequency)
 490                 dev_priv->render_reclock_avail = true;
 491 }
 492
 493 static void
 494 parse_edp(struct drm_i915_private *dev_priv, struct bdb_header *bdb)
 495 {
 496         struct bdb_edp *edp;
 497         struct edp_power_seq *edp_pps;
 498         struct edp_link_params *edp_link_params;
 499
 500         edp = find_section(bdb, BDB_EDP);
 501         if (!edp) {
 502                 if (SUPPORTS_EDP(dev_priv->dev) && dev_priv->edp.support) {
 503                         DRM_DEBUG_KMS("No eDP BDB found but eDP panel "
 504                                       "supported, assume %dbpp panel color "
 505                                       "depth.\n",
 506                                       dev_priv->edp.bpp);
 507                 }
 508                 return;
 509         }
 510
 511         switch ((edp->color_depth >> (panel_type * 2)) & 3) {
 512         case EDP_18BPP:
 513                 dev_priv->edp.bpp = 18;
 514                 break;
 515         case EDP_24BPP:
 516                 dev_priv->edp.bpp = 24;
 517                 break;
 518         case EDP_30BPP:
 519                 dev_priv->edp.bpp = 30;
 520                 break;
 521         }
 522
 523         /* Get the eDP sequencing and link info */
 524         edp_pps = &edp->power_seqs[panel_type];
 525         edp_link_params = &edp->link_params[panel_type];
 526
 527         dev_priv->edp.pps = *edp_pps;
 528
 529         dev_priv->edp.rate = edp_link_params->rate ? DP_LINK_BW_2_7 :
 530                 DP_LINK_BW_1_62;
 531         switch (edp_link_params->lanes) {
 532         case 0:
 533                 dev_priv->edp.lanes = 1;
 534                 break;
 535         case 1:
 536                 dev_priv->edp.lanes = 2;
 537                 break;
 538         case 3:
 539         default:
 540                 dev_priv->edp.lanes = 4;
 541                 break;
 542         }
 543         switch (edp_link_params->preemphasis) {
 544         case 0:
 545                 dev_priv->edp.preemphasis = DP_TRAIN_PRE_EMPHASIS_0;
 546                 break;
 547         case 1:
 548                 dev_priv->edp.preemphasis = DP_TRAIN_PRE_EMPHASIS_3_5;
 549                 break;
 550         case 2:
 551                 dev_priv->edp.preemphasis = DP_TRAIN_PRE_EMPHASIS_6;
 552                 break;
 553         case 3:
 554                 dev_priv->edp.preemphasis = DP_TRAIN_PRE_EMPHASIS_9_5;
 555                 break;
 556         }
 557         switch (edp_link_params->vswing) {
 558         case 0:
 559                 dev_priv->edp.vswing = DP_TRAIN_VOLTAGE_SWING_400;
 560                 break;
 561         case 1:
 562                 dev_priv->edp.vswing = DP_TRAIN_VOLTAGE_SWING_600;
 563                 break;
 564         case 2:
 565                 dev_priv->edp.vswing = DP_TRAIN_VOLTAGE_SWING_800;
 566                 break;
 567         case 3:
 568                 dev_priv->edp.vswing = DP_TRAIN_VOLTAGE_SWING_1200;
 569                 break;
 570         }
 571 }
 572
 573 static void
 574 parse_device_mapping(struct drm_i915_private *dev_priv,
 575                        struct bdb_header *bdb)
 576 {
 577         struct bdb_general_definitions *p_defs;
 578         struct child_device_config *p_child, *child_dev_ptr;
 579         int i, child_device_num, count;
 580         u16     block_size;
 581
 582         p_defs = find_section(bdb, BDB_GENERAL_DEFINITIONS);
 583         if (!p_defs) {
 584                 DRM_DEBUG_KMS("No general definition block is found, no devices defined.\n");
 585                 return;
 586         }
 587         /* judge whether the size of child device meets the requirements.
 588          * If the child device size obtained from general definition block
 589          * is different with sizeof(struct child_device_config), skip the
 590          * parsing of sdvo device info
 591          */
 592         if (p_defs->child_dev_size != sizeof(*p_child)) {
 593                 /* different child dev size . Ignore it */
 594                 DRM_DEBUG_KMS("different child size is found. Invalid.\n");
 595                 return;
 596         }
 597         /* get the block size of general definitions */
 598         block_size = get_blocksize(p_defs);
 599         /* get the number of child device */
 600         child_device_num = (block_size - sizeof(*p_defs)) /
 601                                 sizeof(*p_child);
 602         count = 0;
 603         /* get the number of child device that is present */
 604         for (i = 0; i < child_device_num; i++) {
 605                 p_child = &(p_defs->devices[i]);
 606                 if (!p_child->device_type) {
 607                         /* skip the device block if device type is invalid */
 608                         continue;
 609                 }
 610                 count++;
 611         }
 612         if (!count) {
 613                 DRM_DEBUG_KMS("no child dev is parsed from VBT\n");
 614                 return;
 615         }
 616         dev_priv->child_dev = kcalloc(count, sizeof(*p_child), GFP_KERNEL);
 617         if (!dev_priv->child_dev) {
 618                 DRM_DEBUG_KMS("No memory space for child device\n");
 619                 return;
 620         }
 621
 622         dev_priv->child_dev_num = count;
 623         count = 0;
 624         for (i = 0; i < child_device_num; i++) {
 625                 p_child = &(p_defs->devices[i]);
 626                 if (!p_child->device_type) {
 627                         /* skip the device block if device type is invalid */
 628                         continue;
 629                 }
 630                 child_dev_ptr = dev_priv->child_dev + count;
 631                 count++;
 632                 memcpy((void *)child_dev_ptr, (void *)p_child,
 633                                         sizeof(*p_child));
 634         }
 635         return;
 636 }
 637
 638 static void
 639 init_vbt_defaults(struct drm_i915_private *dev_priv)
 640 {
 641         struct drm_device *dev = dev_priv->dev;
 642
 643         dev_priv->crt_ddc_pin = GMBUS_PORT_VGADDC;
 644
 645         /* LFP panel data */
 646         dev_priv->lvds_dither = 1;
 647         dev_priv->lvds_vbt = 0;
 648
 649         /* SDVO panel data */
 650         dev_priv->sdvo_lvds_vbt_mode = NULL;
 651
 652         /* general features */
 653         dev_priv->int_tv_support = 1;
 654         dev_priv->int_crt_support = 1;
 655
 656         /* Default to using SSC */
 657         dev_priv->lvds_use_ssc = 1;
 658         dev_priv->lvds_ssc_freq = intel_bios_ssc_frequency(dev, 1);
 659         DRM_DEBUG_KMS("Set default to SSC at %dMHz\n", dev_priv->lvds_ssc_freq);
 660
 661         /* eDP data */
 662         dev_priv->edp.bpp = 18;
 663 }
 664
 665 static int __init intel_no_opregion_vbt_callback(const struct dmi_system_id *id)
 666 {
 667         DRM_DEBUG_KMS("Falling back to manually reading VBT from "
 668                       "VBIOS ROM for %s\n",
 669                       id->ident);
 670         return 1;
 671 }
 672
 673 static const struct dmi_system_id intel_no_opregion_vbt[] = {
 674         {
 675                 .callback = intel_no_opregion_vbt_callback,
 676                 .ident = "ThinkCentre A57",
 677                 .matches = {
 678                         DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
 679                         DMI_MATCH(DMI_PRODUCT_NAME, "97027RG"),
 680                 },
 681         },
 682         { }
 683 };
 684
 685 /**
 686  * intel_parse_bios - find VBT and initialize settings from the BIOS
 687  * @dev: DRM device
 688  *
 689  * Loads the Video BIOS and checks that the VBT exists.  Sets scratch registers
 690  * to appropriate values.
 691  *
 692  * Returns 0 on success, nonzero on failure.
 693  */
 694 int
 695 intel_parse_bios(struct drm_device *dev)
 696 {
 697         struct drm_i915_private *dev_priv = dev->dev_private;
 698         struct pci_dev *pdev = dev->pdev;
 699         struct bdb_header *bdb = NULL;
 700         u8 __iomem *bios = NULL;
 701
 702         init_vbt_defaults(dev_priv);
 703
 704         /* XXX Should this validation be moved to intel_opregion.c? */
 705         if (!dmi_check_system(intel_no_opregion_vbt) && dev_priv->opregion.vbt) {
 706                 struct vbt_header *vbt = dev_priv->opregion.vbt;
 707                 if (memcmp(vbt->signature, "$VBT", 4) == 0) {
 708                         DRM_DEBUG_KMS("Using VBT from OpRegion: %20s\n",
 709                                          vbt->signature);
 710                         bdb = (struct bdb_header *)((char *)vbt + vbt->bdb_offset);
 711                 } else
 712                         dev_priv->opregion.vbt = NULL;
 713         }
 714
 715         if (bdb == NULL) {
 716                 struct vbt_header *vbt = NULL;
 717                 size_t size;
 718                 int i;
 719
 720                 bios = pci_map_rom(pdev, &size);
 721                 if (!bios)
 722                         return -1;
 723
 724                 /* Scour memory looking for the VBT signature */
 725                 for (i = 0; i + 4 < size; i++) {
 726                         if (!memcmp(bios + i, "$VBT", 4)) {
 727                                 vbt = (struct vbt_header *)(bios + i);
 728                                 break;
 729                         }
 730                 }
 731
 732                 if (!vbt) {
 733                         DRM_DEBUG_DRIVER("VBT signature missing\n");
 734                         pci_unmap_rom(pdev, bios);
 735                         return -1;
 736                 }
 737
 738                 bdb = (struct bdb_header *)(bios + i + vbt->bdb_offset);
 739         }
 740
 741         /* Grab useful general definitions */
 742         parse_general_features(dev_priv, bdb);
 743         parse_general_definitions(dev_priv, bdb);
 744         parse_lfp_panel_data(dev_priv, bdb);
 745         parse_sdvo_panel_data(dev_priv, bdb);
 746         parse_sdvo_device_mapping(dev_priv, bdb);
 747         parse_device_mapping(dev_priv, bdb);
 748         parse_driver_features(dev_priv, bdb);
 749         parse_edp(dev_priv, bdb);
 750
 751         if (bios)
 752                 pci_unmap_rom(pdev, bios);
 753
 754         return 0;
 755 }
 756
 757 /* Ensure that vital registers have been initialised, even if the BIOS
 758  * is absent or just failing to do its job.
 759  */
 760 void intel_setup_bios(struct drm_device *dev)
 761 {
 762         struct drm_i915_private *dev_priv = dev->dev_private;
 763
 764          /* Set the Panel Power On/Off timings if uninitialized. */
 765         if ((I915_READ(PP_ON_DELAYS) == 0) && (I915_READ(PP_OFF_DELAYS) == 0)) {
 766                 /* Set T2 to 40ms and T5 to 200ms */
 767                 I915_WRITE(PP_ON_DELAYS, 0x019007d0);
 768
 769                 /* Set T3 to 35ms and Tx to 200ms */
 770                 I915_WRITE(PP_OFF_DELAYS, 0x015e07d0);
 771         }
 772 }