drivers/gpu/drm/i915/intel_dram.c

   1 // SPDX-License-Identifier: MIT
   2 /*
   3  * Copyright © 2020 Intel Corporation
   4  */
   5
   6 #include "i915_drv.h"
   7 #include "intel_dram.h"
   8
   9 struct dram_dimm_info {
  10         u16 size;
  11         u8 width, ranks;
  12 };
  13
  14 struct dram_channel_info {
  15         struct dram_dimm_info dimm_l, dimm_s;
  16         u8 ranks;
  17         bool is_16gb_dimm;
  18 };
  19
  20 #define DRAM_TYPE_STR(type) [INTEL_DRAM_ ## type] = #type
  21
  22 static const char *intel_dram_type_str(enum intel_dram_type type)
  23 {
  24         static const char * const str[] = {
  25                 DRAM_TYPE_STR(UNKNOWN),
  26                 DRAM_TYPE_STR(DDR3),
  27                 DRAM_TYPE_STR(DDR4),
  28                 DRAM_TYPE_STR(LPDDR3),
  29                 DRAM_TYPE_STR(LPDDR4),
  30         };
  31
  32         if (type >= ARRAY_SIZE(str))
  33                 type = INTEL_DRAM_UNKNOWN;
  34
  35         return str[type];
  36 }
  37
  38 #undef DRAM_TYPE_STR
  39
  40 static int intel_dimm_num_devices(const struct dram_dimm_info *dimm)
  41 {
  42         return dimm->ranks * 64 / (dimm->width ?: 1);
  43 }
  44
  45 /* Returns total Gb for the whole DIMM */
  46 static int skl_get_dimm_size(u16 val)
  47 {
  48         return (val & SKL_DRAM_SIZE_MASK) * 8;
  49 }
  50
  51 static int skl_get_dimm_width(u16 val)
  52 {
  53         if (skl_get_dimm_size(val) == 0)
  54                 return 0;
  55
  56         switch (val & SKL_DRAM_WIDTH_MASK) {
  57         case SKL_DRAM_WIDTH_X8:
  58         case SKL_DRAM_WIDTH_X16:
  59         case SKL_DRAM_WIDTH_X32:
  60                 val = (val & SKL_DRAM_WIDTH_MASK) >> SKL_DRAM_WIDTH_SHIFT;
  61                 return 8 << val;
  62         default:
  63                 MISSING_CASE(val);
  64                 return 0;
  65         }
  66 }
  67
  68 static int skl_get_dimm_ranks(u16 val)
  69 {
  70         if (skl_get_dimm_size(val) == 0)
  71                 return 0;
  72
  73         val = (val & SKL_DRAM_RANK_MASK) >> SKL_DRAM_RANK_SHIFT;
  74
  75         return val + 1;
  76 }
  77
  78 /* Returns total Gb for the whole DIMM */
  79 static int cnl_get_dimm_size(u16 val)
  80 {
  81         return (val & CNL_DRAM_SIZE_MASK) * 8 / 2;
  82 }
  83
  84 static int cnl_get_dimm_width(u16 val)
  85 {
  86         if (cnl_get_dimm_size(val) == 0)
  87                 return 0;
  88
  89         switch (val & CNL_DRAM_WIDTH_MASK) {
  90         case CNL_DRAM_WIDTH_X8:
  91         case CNL_DRAM_WIDTH_X16:
  92         case CNL_DRAM_WIDTH_X32:
  93                 val = (val & CNL_DRAM_WIDTH_MASK) >> CNL_DRAM_WIDTH_SHIFT;
  94                 return 8 << val;
  95         default:
  96                 MISSING_CASE(val);
  97                 return 0;
  98         }
  99 }
 100
 101 static int cnl_get_dimm_ranks(u16 val)
 102 {
 103         if (cnl_get_dimm_size(val) == 0)
 104                 return 0;
 105
 106         val = (val & CNL_DRAM_RANK_MASK) >> CNL_DRAM_RANK_SHIFT;
 107
 108         return val + 1;
 109 }
 110
 111 static bool
 112 skl_is_16gb_dimm(const struct dram_dimm_info *dimm)
 113 {
 114         /* Convert total Gb to Gb per DRAM device */
 115         return dimm->size / (intel_dimm_num_devices(dimm) ?: 1) == 16;
 116 }
 117
 118 static void
 119 skl_dram_get_dimm_info(struct drm_i915_private *i915,
 120                        struct dram_dimm_info *dimm,
 121                        int channel, char dimm_name, u16 val)
 122 {
 123         if (INTEL_GEN(i915) >= 10) {
 124                 dimm->size = cnl_get_dimm_size(val);
 125                 dimm->width = cnl_get_dimm_width(val);
 126                 dimm->ranks = cnl_get_dimm_ranks(val);
 127         } else {
 128                 dimm->size = skl_get_dimm_size(val);
 129                 dimm->width = skl_get_dimm_width(val);
 130                 dimm->ranks = skl_get_dimm_ranks(val);
 131         }
 132
 133         drm_dbg_kms(&i915->drm,
 134                     "CH%u DIMM %c size: %u Gb, width: X%u, ranks: %u, 16Gb DIMMs: %s\n",
 135                     channel, dimm_name, dimm->size, dimm->width, dimm->ranks,
 136                     yesno(skl_is_16gb_dimm(dimm)));
 137 }
 138
 139 static int
 140 skl_dram_get_channel_info(struct drm_i915_private *i915,
 141                           struct dram_channel_info *ch,
 142                           int channel, u32 val)
 143 {
 144         skl_dram_get_dimm_info(i915, &ch->dimm_l,
 145                                channel, 'L', val & 0xffff);
 146         skl_dram_get_dimm_info(i915, &ch->dimm_s,
 147                                channel, 'S', val >> 16);
 148
 149         if (ch->dimm_l.size == 0 && ch->dimm_s.size == 0) {
 150                 drm_dbg_kms(&i915->drm, "CH%u not populated\n", channel);
 151                 return -EINVAL;
 152         }
 153
 154         if (ch->dimm_l.ranks == 2 || ch->dimm_s.ranks == 2)
 155                 ch->ranks = 2;
 156         else if (ch->dimm_l.ranks == 1 && ch->dimm_s.ranks == 1)
 157                 ch->ranks = 2;
 158         else
 159                 ch->ranks = 1;
 160
 161         ch->is_16gb_dimm = skl_is_16gb_dimm(&ch->dimm_l) ||
 162                 skl_is_16gb_dimm(&ch->dimm_s);
 163
 164         drm_dbg_kms(&i915->drm, "CH%u ranks: %u, 16Gb DIMMs: %s\n",
 165                     channel, ch->ranks, yesno(ch->is_16gb_dimm));
 166
 167         return 0;
 168 }
 169
 170 static bool
 171 intel_is_dram_symmetric(const struct dram_channel_info *ch0,
 172                         const struct dram_channel_info *ch1)
 173 {
 174         return !memcmp(ch0, ch1, sizeof(*ch0)) &&
 175                 (ch0->dimm_s.size == 0 ||
 176                  !memcmp(&ch0->dimm_l, &ch0->dimm_s, sizeof(ch0->dimm_l)));
 177 }
 178
 179 static int
 180 skl_dram_get_channels_info(struct drm_i915_private *i915)
 181 {
 182         struct dram_info *dram_info = &i915->dram_info;
 183         struct dram_channel_info ch0 = {}, ch1 = {};
 184         u32 val;
 185         int ret;
 186
 187         val = intel_uncore_read(&i915->uncore,
 188                                 SKL_MAD_DIMM_CH0_0_0_0_MCHBAR_MCMAIN);
 189         ret = skl_dram_get_channel_info(i915, &ch0, 0, val);
 190         if (ret == 0)
 191                 dram_info->num_channels++;
 192
 193         val = intel_uncore_read(&i915->uncore,
 194                                 SKL_MAD_DIMM_CH1_0_0_0_MCHBAR_MCMAIN);
 195         ret = skl_dram_get_channel_info(i915, &ch1, 1, val);
 196         if (ret == 0)
 197                 dram_info->num_channels++;
 198
 199         if (dram_info->num_channels == 0) {
 200                 drm_info(&i915->drm, "Number of memory channels is zero\n");
 201                 return -EINVAL;
 202         }
 203
 204         /*
 205          * If any of the channel is single rank channel, worst case output
 206          * will be same as if single rank memory, so consider single rank
 207          * memory.
 208          */
 209         if (ch0.ranks == 1 || ch1.ranks == 1)
 210                 dram_info->ranks = 1;
 211         else
 212                 dram_info->ranks = max(ch0.ranks, ch1.ranks);
 213
 214         if (dram_info->ranks == 0) {
 215                 drm_info(&i915->drm, "couldn't get memory rank information\n");
 216                 return -EINVAL;
 217         }
 218
 219         dram_info->is_16gb_dimm = ch0.is_16gb_dimm || ch1.is_16gb_dimm;
 220
 221         dram_info->symmetric_memory = intel_is_dram_symmetric(&ch0, &ch1);
 222
 223         drm_dbg_kms(&i915->drm, "Memory configuration is symmetric? %s\n",
 224                     yesno(dram_info->symmetric_memory));
 225
 226         return 0;
 227 }
 228
 229 static enum intel_dram_type
 230 skl_get_dram_type(struct drm_i915_private *i915)
 231 {
 232         u32 val;
 233
 234         val = intel_uncore_read(&i915->uncore,
 235                                 SKL_MAD_INTER_CHANNEL_0_0_0_MCHBAR_MCMAIN);
 236
 237         switch (val & SKL_DRAM_DDR_TYPE_MASK) {
 238         case SKL_DRAM_DDR_TYPE_DDR3:
 239                 return INTEL_DRAM_DDR3;
 240         case SKL_DRAM_DDR_TYPE_DDR4:
 241                 return INTEL_DRAM_DDR4;
 242         case SKL_DRAM_DDR_TYPE_LPDDR3:
 243                 return INTEL_DRAM_LPDDR3;
 244         case SKL_DRAM_DDR_TYPE_LPDDR4:
 245                 return INTEL_DRAM_LPDDR4;
 246         default:
 247                 MISSING_CASE(val);
 248                 return INTEL_DRAM_UNKNOWN;
 249         }
 250 }
 251
 252 static int
 253 skl_get_dram_info(struct drm_i915_private *i915)
 254 {
 255         struct dram_info *dram_info = &i915->dram_info;
 256         u32 mem_freq_khz, val;
 257         int ret;
 258
 259         dram_info->type = skl_get_dram_type(i915);
 260         drm_dbg_kms(&i915->drm, "DRAM type: %s\n",
 261                     intel_dram_type_str(dram_info->type));
 262
 263         ret = skl_dram_get_channels_info(i915);
 264         if (ret)
 265                 return ret;
 266
 267         val = intel_uncore_read(&i915->uncore,
 268                                 SKL_MC_BIOS_DATA_0_0_0_MCHBAR_PCU);
 269         mem_freq_khz = DIV_ROUND_UP((val & SKL_REQ_DATA_MASK) *
 270                                     SKL_MEMORY_FREQ_MULTIPLIER_HZ, 1000);
 271
 272         dram_info->bandwidth_kbps = dram_info->num_channels *
 273                 mem_freq_khz * 8;
 274
 275         if (dram_info->bandwidth_kbps == 0) {
 276                 drm_info(&i915->drm,
 277                          "Couldn't get system memory bandwidth\n");
 278                 return -EINVAL;
 279         }
 280
 281         dram_info->valid = true;
 282         return 0;
 283 }
 284
 285 /* Returns Gb per DRAM device */
 286 static int bxt_get_dimm_size(u32 val)
 287 {
 288         switch (val & BXT_DRAM_SIZE_MASK) {
 289         case BXT_DRAM_SIZE_4GBIT:
 290                 return 4;
 291         case BXT_DRAM_SIZE_6GBIT:
 292                 return 6;
 293         case BXT_DRAM_SIZE_8GBIT:
 294                 return 8;
 295         case BXT_DRAM_SIZE_12GBIT:
 296                 return 12;
 297         case BXT_DRAM_SIZE_16GBIT:
 298                 return 16;
 299         default:
 300                 MISSING_CASE(val);
 301                 return 0;
 302         }
 303 }
 304
 305 static int bxt_get_dimm_width(u32 val)
 306 {
 307         if (!bxt_get_dimm_size(val))
 308                 return 0;
 309
 310         val = (val & BXT_DRAM_WIDTH_MASK) >> BXT_DRAM_WIDTH_SHIFT;
 311
 312         return 8 << val;
 313 }
 314
 315 static int bxt_get_dimm_ranks(u32 val)
 316 {
 317         if (!bxt_get_dimm_size(val))
 318                 return 0;
 319
 320         switch (val & BXT_DRAM_RANK_MASK) {
 321         case BXT_DRAM_RANK_SINGLE:
 322                 return 1;
 323         case BXT_DRAM_RANK_DUAL:
 324                 return 2;
 325         default:
 326                 MISSING_CASE(val);
 327                 return 0;
 328         }
 329 }
 330
 331 static enum intel_dram_type bxt_get_dimm_type(u32 val)
 332 {
 333         if (!bxt_get_dimm_size(val))
 334                 return INTEL_DRAM_UNKNOWN;
 335
 336         switch (val & BXT_DRAM_TYPE_MASK) {
 337         case BXT_DRAM_TYPE_DDR3:
 338                 return INTEL_DRAM_DDR3;
 339         case BXT_DRAM_TYPE_LPDDR3:
 340                 return INTEL_DRAM_LPDDR3;
 341         case BXT_DRAM_TYPE_DDR4:
 342                 return INTEL_DRAM_DDR4;
 343         case BXT_DRAM_TYPE_LPDDR4:
 344                 return INTEL_DRAM_LPDDR4;
 345         default:
 346                 MISSING_CASE(val);
 347                 return INTEL_DRAM_UNKNOWN;
 348         }
 349 }
 350
 351 static void bxt_get_dimm_info(struct dram_dimm_info *dimm, u32 val)
 352 {
 353         dimm->width = bxt_get_dimm_width(val);
 354         dimm->ranks = bxt_get_dimm_ranks(val);
 355
 356         /*
 357          * Size in register is Gb per DRAM device. Convert to total
 358          * Gb to match the way we report this for non-LP platforms.
 359          */
 360         dimm->size = bxt_get_dimm_size(val) * intel_dimm_num_devices(dimm);
 361 }
 362
 363 static int bxt_get_dram_info(struct drm_i915_private *i915)
 364 {
 365         struct dram_info *dram_info = &i915->dram_info;
 366         u32 dram_channels;
 367         u32 mem_freq_khz, val;
 368         u8 num_active_channels;
 369         int i;
 370
 371         val = intel_uncore_read(&i915->uncore, BXT_P_CR_MC_BIOS_REQ_0_0_0);
 372         mem_freq_khz = DIV_ROUND_UP((val & BXT_REQ_DATA_MASK) *
 373                                     BXT_MEMORY_FREQ_MULTIPLIER_HZ, 1000);
 374
 375         dram_channels = val & BXT_DRAM_CHANNEL_ACTIVE_MASK;
 376         num_active_channels = hweight32(dram_channels);
 377
 378         /* Each active bit represents 4-byte channel */
 379         dram_info->bandwidth_kbps = (mem_freq_khz * num_active_channels * 4);
 380
 381         if (dram_info->bandwidth_kbps == 0) {
 382                 drm_info(&i915->drm,
 383                          "Couldn't get system memory bandwidth\n");
 384                 return -EINVAL;
 385         }
 386
 387         /*
 388          * Now read each DUNIT8/9/10/11 to check the rank of each dimms.
 389          */
 390         for (i = BXT_D_CR_DRP0_DUNIT_START; i <= BXT_D_CR_DRP0_DUNIT_END; i++) {
 391                 struct dram_dimm_info dimm;
 392                 enum intel_dram_type type;
 393
 394                 val = intel_uncore_read(&i915->uncore, BXT_D_CR_DRP0_DUNIT(i));
 395                 if (val == 0xFFFFFFFF)
 396                         continue;
 397
 398                 dram_info->num_channels++;
 399
 400                 bxt_get_dimm_info(&dimm, val);
 401                 type = bxt_get_dimm_type(val);
 402
 403                 drm_WARN_ON(&i915->drm, type != INTEL_DRAM_UNKNOWN &&
 404                             dram_info->type != INTEL_DRAM_UNKNOWN &&
 405                             dram_info->type != type);
 406
 407                 drm_dbg_kms(&i915->drm,
 408                             "CH%u DIMM size: %u Gb, width: X%u, ranks: %u, type: %s\n",
 409                             i - BXT_D_CR_DRP0_DUNIT_START,
 410                             dimm.size, dimm.width, dimm.ranks,
 411                             intel_dram_type_str(type));
 412
 413                 /*
 414                  * If any of the channel is single rank channel,
 415                  * worst case output will be same as if single rank
 416                  * memory, so consider single rank memory.
 417                  */
 418                 if (dram_info->ranks == 0)
 419                         dram_info->ranks = dimm.ranks;
 420                 else if (dimm.ranks == 1)
 421                         dram_info->ranks = 1;
 422
 423                 if (type != INTEL_DRAM_UNKNOWN)
 424                         dram_info->type = type;
 425         }
 426
 427         if (dram_info->type == INTEL_DRAM_UNKNOWN || dram_info->ranks == 0) {
 428                 drm_info(&i915->drm, "couldn't get memory information\n");
 429                 return -EINVAL;
 430         }
 431
 432         dram_info->valid = true;
 433
 434         return 0;
 435 }
 436
 437 void intel_dram_detect(struct drm_i915_private *i915)
 438 {
 439         struct dram_info *dram_info = &i915->dram_info;
 440         int ret;
 441
 442         /*
 443          * Assume 16Gb DIMMs are present until proven otherwise.
 444          * This is only used for the level 0 watermark latency
 445          * w/a which does not apply to bxt/glk.
 446          */
 447         dram_info->is_16gb_dimm = !IS_GEN9_LP(i915);
 448
 449         if (INTEL_GEN(i915) < 9 || !HAS_DISPLAY(i915))
 450                 return;
 451
 452         if (IS_GEN9_LP(i915))
 453                 ret = bxt_get_dram_info(i915);
 454         else
 455                 ret = skl_get_dram_info(i915);
 456         if (ret)
 457                 return;
 458
 459         drm_dbg_kms(&i915->drm, "DRAM bandwidth: %u kBps, channels: %u\n",
 460                     dram_info->bandwidth_kbps, dram_info->num_channels);
 461
 462         drm_dbg_kms(&i915->drm, "DRAM ranks: %u, 16Gb DIMMs: %s\n",
 463                     dram_info->ranks, yesno(dram_info->is_16gb_dimm));
 464 }
 465
 466 static u32 gen9_edram_size_mb(struct drm_i915_private *i915, u32 cap)
 467 {
 468         static const u8 ways[8] = { 4, 8, 12, 16, 16, 16, 16, 16 };
 469         static const u8 sets[4] = { 1, 1, 2, 2 };
 470
 471         return EDRAM_NUM_BANKS(cap) *
 472                 ways[EDRAM_WAYS_IDX(cap)] *
 473                 sets[EDRAM_SETS_IDX(cap)];
 474 }
 475
 476 void intel_dram_edram_detect(struct drm_i915_private *i915)
 477 {
 478         u32 edram_cap = 0;
 479
 480         if (!(IS_HASWELL(i915) || IS_BROADWELL(i915) || INTEL_GEN(i915) >= 9))
 481                 return;
 482
 483         edram_cap = __raw_uncore_read32(&i915->uncore, HSW_EDRAM_CAP);
 484
 485         /* NB: We can't write IDICR yet because we don't have gt funcs set up */
 486
 487         if (!(edram_cap & EDRAM_ENABLED))
 488                 return;
 489
 490         /*
 491          * The needed capability bits for size calculation are not there with
 492          * pre gen9 so return 128MB always.
 493          */
 494         if (INTEL_GEN(i915) < 9)
 495                 i915->edram_size_mb = 128;
 496         else
 497                 i915->edram_size_mb = gen9_edram_size_mb(i915, edram_cap);
 498
 499         drm_info(&i915->drm, "Found %uMB of eDRAM\n", i915->edram_size_mb);
 500 }