drivers/edac/x38_edac.c

   1 /*
   2  * Intel X38 Memory Controller kernel module
   3  * Copyright (C) 2008 Cluster Computing, Inc.
   4  *
   5  * This file may be distributed under the terms of the
   6  * GNU General Public License.
   7  *
   8  * This file is based on i3200_edac.c
   9  *
  10  */
  11
  12 #include <linux/module.h>
  13 #include <linux/init.h>
  14 #include <linux/pci.h>
  15 #include <linux/pci_ids.h>
  16 #include <linux/edac.h>
  17
  18 #include <linux/io-64-nonatomic-lo-hi.h>
  19 #include "edac_module.h"
  20
  21 #define EDAC_MOD_STR            "x38_edac"
  22
  23 #define PCI_DEVICE_ID_INTEL_X38_HB      0x29e0
  24
  25 #define X38_RANKS               8
  26 #define X38_RANKS_PER_CHANNEL   4
  27 #define X38_CHANNELS            2
  28
  29 /* Intel X38 register addresses - device 0 function 0 - DRAM Controller */
  30
  31 #define X38_MCHBAR_LOW  0x48    /* MCH Memory Mapped Register BAR */
  32 #define X38_MCHBAR_HIGH 0x4c
  33 #define X38_MCHBAR_MASK 0xfffffc000ULL  /* bits 35:14 */
  34 #define X38_MMR_WINDOW_SIZE     16384
  35
  36 #define X38_TOM 0xa0    /* Top of Memory (16b)
  37                                  *
  38                                  * 15:10 reserved
  39                                  *  9:0  total populated physical memory
  40                                  */
  41 #define X38_TOM_MASK    0x3ff   /* bits 9:0 */
  42 #define X38_TOM_SHIFT 26        /* 64MiB grain */
  43
  44 #define X38_ERRSTS      0xc8    /* Error Status Register (16b)
  45                                  *
  46                                  * 15    reserved
  47                                  * 14    Isochronous TBWRR Run Behind FIFO Full
  48                                  *       (ITCV)
  49                                  * 13    Isochronous TBWRR Run Behind FIFO Put
  50                                  *       (ITSTV)
  51                                  * 12    reserved
  52                                  * 11    MCH Thermal Sensor Event
  53                                  *       for SMI/SCI/SERR (GTSE)
  54                                  * 10    reserved
  55                                  *  9    LOCK to non-DRAM Memory Flag (LCKF)
  56                                  *  8    reserved
  57                                  *  7    DRAM Throttle Flag (DTF)
  58                                  *  6:2  reserved
  59                                  *  1    Multi-bit DRAM ECC Error Flag (DMERR)
  60                                  *  0    Single-bit DRAM ECC Error Flag (DSERR)
  61                                  */
  62 #define X38_ERRSTS_UE           0x0002
  63 #define X38_ERRSTS_CE           0x0001
  64 #define X38_ERRSTS_BITS (X38_ERRSTS_UE | X38_ERRSTS_CE)
  65
  66
  67 /* Intel  MMIO register space - device 0 function 0 - MMR space */
  68
  69 #define X38_C0DRB       0x200   /* Channel 0 DRAM Rank Boundary (16b x 4)
  70                                  *
  71                                  * 15:10 reserved
  72                                  *  9:0  Channel 0 DRAM Rank Boundary Address
  73                                  */
  74 #define X38_C1DRB       0x600   /* Channel 1 DRAM Rank Boundary (16b x 4) */
  75 #define X38_DRB_MASK    0x3ff   /* bits 9:0 */
  76 #define X38_DRB_SHIFT 26        /* 64MiB grain */
  77
  78 #define X38_C0ECCERRLOG 0x280   /* Channel 0 ECC Error Log (64b)
  79                                  *
  80                                  * 63:48 Error Column Address (ERRCOL)
  81                                  * 47:32 Error Row Address (ERRROW)
  82                                  * 31:29 Error Bank Address (ERRBANK)
  83                                  * 28:27 Error Rank Address (ERRRANK)
  84                                  * 26:24 reserved
  85                                  * 23:16 Error Syndrome (ERRSYND)
  86                                  * 15: 2 reserved
  87                                  *    1  Multiple Bit Error Status (MERRSTS)
  88                                  *    0  Correctable Error Status (CERRSTS)
  89                                  */
  90 #define X38_C1ECCERRLOG 0x680   /* Channel 1 ECC Error Log (64b) */
  91 #define X38_ECCERRLOG_CE        0x1
  92 #define X38_ECCERRLOG_UE        0x2
  93 #define X38_ECCERRLOG_RANK_BITS 0x18000000
  94 #define X38_ECCERRLOG_SYNDROME_BITS     0xff0000
  95
  96 #define X38_CAPID0 0xe0 /* see P.94 of spec for details */
  97
  98 static int x38_channel_num;
  99
 100 static int how_many_channel(struct pci_dev *pdev)
 101 {
 102         unsigned char capid0_8b; /* 8th byte of CAPID0 */
 103
 104         pci_read_config_byte(pdev, X38_CAPID0 + 8, &capid0_8b);
 105         if (capid0_8b & 0x20) { /* check DCD: Dual Channel Disable */
 106                 edac_dbg(0, "In single channel mode\n");
 107                 x38_channel_num = 1;
 108         } else {
 109                 edac_dbg(0, "In dual channel mode\n");
 110                 x38_channel_num = 2;
 111         }
 112
 113         return x38_channel_num;
 114 }
 115
 116 static unsigned long eccerrlog_syndrome(u64 log)
 117 {
 118         return (log & X38_ECCERRLOG_SYNDROME_BITS) >> 16;
 119 }
 120
 121 static int eccerrlog_row(int channel, u64 log)
 122 {
 123         return ((log & X38_ECCERRLOG_RANK_BITS) >> 27) |
 124                 (channel * X38_RANKS_PER_CHANNEL);
 125 }
 126
 127 enum x38_chips {
 128         X38 = 0,
 129 };
 130
 131 struct x38_dev_info {
 132         const char *ctl_name;
 133 };
 134
 135 struct x38_error_info {
 136         u16 errsts;
 137         u16 errsts2;
 138         u64 eccerrlog[X38_CHANNELS];
 139 };
 140
 141 static const struct x38_dev_info x38_devs[] = {
 142         [X38] = {
 143                 .ctl_name = "x38"},
 144 };
 145
 146 static struct pci_dev *mci_pdev;
 147 static int x38_registered = 1;
 148
 149
 150 static void x38_clear_error_info(struct mem_ctl_info *mci)
 151 {
 152         struct pci_dev *pdev;
 153
 154         pdev = to_pci_dev(mci->pdev);
 155
 156         /*
 157          * Clear any error bits.
 158          * (Yes, we really clear bits by writing 1 to them.)
 159          */
 160         pci_write_bits16(pdev, X38_ERRSTS, X38_ERRSTS_BITS,
 161                          X38_ERRSTS_BITS);
 162 }
 163
 164 static void x38_get_and_clear_error_info(struct mem_ctl_info *mci,
 165                                  struct x38_error_info *info)
 166 {
 167         struct pci_dev *pdev;
 168         void __iomem *window = mci->pvt_info;
 169
 170         pdev = to_pci_dev(mci->pdev);
 171
 172         /*
 173          * This is a mess because there is no atomic way to read all the
 174          * registers at once and the registers can transition from CE being
 175          * overwritten by UE.
 176          */
 177         pci_read_config_word(pdev, X38_ERRSTS, &info->errsts);
 178         if (!(info->errsts & X38_ERRSTS_BITS))
 179                 return;
 180
 181         info->eccerrlog[0] = lo_hi_readq(window + X38_C0ECCERRLOG);
 182         if (x38_channel_num == 2)
 183                 info->eccerrlog[1] = lo_hi_readq(window + X38_C1ECCERRLOG);
 184
 185         pci_read_config_word(pdev, X38_ERRSTS, &info->errsts2);
 186
 187         /*
 188          * If the error is the same for both reads then the first set
 189          * of reads is valid.  If there is a change then there is a CE
 190          * with no info and the second set of reads is valid and
 191          * should be UE info.
 192          */
 193         if ((info->errsts ^ info->errsts2) & X38_ERRSTS_BITS) {
 194                 info->eccerrlog[0] = lo_hi_readq(window + X38_C0ECCERRLOG);
 195                 if (x38_channel_num == 2)
 196                         info->eccerrlog[1] =
 197                                 lo_hi_readq(window + X38_C1ECCERRLOG);
 198         }
 199
 200         x38_clear_error_info(mci);
 201 }
 202
 203 static void x38_process_error_info(struct mem_ctl_info *mci,
 204                                 struct x38_error_info *info)
 205 {
 206         int channel;
 207         u64 log;
 208
 209         if (!(info->errsts & X38_ERRSTS_BITS))
 210                 return;
 211
 212         if ((info->errsts ^ info->errsts2) & X38_ERRSTS_BITS) {
 213                 edac_mc_handle_error(HW_EVENT_ERR_UNCORRECTED, mci, 1, 0, 0, 0,
 214                                      -1, -1, -1,
 215                                      "UE overwrote CE", "");
 216                 info->errsts = info->errsts2;
 217         }
 218
 219         for (channel = 0; channel < x38_channel_num; channel++) {
 220                 log = info->eccerrlog[channel];
 221                 if (log & X38_ECCERRLOG_UE) {
 222                         edac_mc_handle_error(HW_EVENT_ERR_UNCORRECTED, mci, 1,
 223                                              0, 0, 0,
 224                                              eccerrlog_row(channel, log),
 225                                              -1, -1,
 226                                              "x38 UE", "");
 227                 } else if (log & X38_ECCERRLOG_CE) {
 228                         edac_mc_handle_error(HW_EVENT_ERR_CORRECTED, mci, 1,
 229                                              0, 0, eccerrlog_syndrome(log),
 230                                              eccerrlog_row(channel, log),
 231                                              -1, -1,
 232                                              "x38 CE", "");
 233                 }
 234         }
 235 }
 236
 237 static void x38_check(struct mem_ctl_info *mci)
 238 {
 239         struct x38_error_info info;
 240
 241         edac_dbg(1, "MC%d\n", mci->mc_idx);
 242         x38_get_and_clear_error_info(mci, &info);
 243         x38_process_error_info(mci, &info);
 244 }
 245
 246 static void __iomem *x38_map_mchbar(struct pci_dev *pdev)
 247 {
 248         union {
 249                 u64 mchbar;
 250                 struct {
 251                         u32 mchbar_low;
 252                         u32 mchbar_high;
 253                 };
 254         } u;
 255         void __iomem *window;
 256
 257         pci_read_config_dword(pdev, X38_MCHBAR_LOW, &u.mchbar_low);
 258         pci_write_config_dword(pdev, X38_MCHBAR_LOW, u.mchbar_low | 0x1);
 259         pci_read_config_dword(pdev, X38_MCHBAR_HIGH, &u.mchbar_high);
 260         u.mchbar &= X38_MCHBAR_MASK;
 261
 262         if (u.mchbar != (resource_size_t)u.mchbar) {
 263                 printk(KERN_ERR
 264                         "x38: mmio space beyond accessible range (0x%llx)\n",
 265                         (unsigned long long)u.mchbar);
 266                 return NULL;
 267         }
 268
 269         window = ioremap_nocache(u.mchbar, X38_MMR_WINDOW_SIZE);
 270         if (!window)
 271                 printk(KERN_ERR "x38: cannot map mmio space at 0x%llx\n",
 272                         (unsigned long long)u.mchbar);
 273
 274         return window;
 275 }
 276
 277
 278 static void x38_get_drbs(void __iomem *window,
 279                         u16 drbs[X38_CHANNELS][X38_RANKS_PER_CHANNEL])
 280 {
 281         int i;
 282
 283         for (i = 0; i < X38_RANKS_PER_CHANNEL; i++) {
 284                 drbs[0][i] = readw(window + X38_C0DRB + 2*i) & X38_DRB_MASK;
 285                 drbs[1][i] = readw(window + X38_C1DRB + 2*i) & X38_DRB_MASK;
 286         }
 287 }
 288
 289 static bool x38_is_stacked(struct pci_dev *pdev,
 290                         u16 drbs[X38_CHANNELS][X38_RANKS_PER_CHANNEL])
 291 {
 292         u16 tom;
 293
 294         pci_read_config_word(pdev, X38_TOM, &tom);
 295         tom &= X38_TOM_MASK;
 296
 297         return drbs[X38_CHANNELS - 1][X38_RANKS_PER_CHANNEL - 1] == tom;
 298 }
 299
 300 static unsigned long drb_to_nr_pages(
 301                         u16 drbs[X38_CHANNELS][X38_RANKS_PER_CHANNEL],
 302                         bool stacked, int channel, int rank)
 303 {
 304         int n;
 305
 306         n = drbs[channel][rank];
 307         if (rank > 0)
 308                 n -= drbs[channel][rank - 1];
 309         if (stacked && (channel == 1) && drbs[channel][rank] ==
 310                                 drbs[channel][X38_RANKS_PER_CHANNEL - 1]) {
 311                 n -= drbs[0][X38_RANKS_PER_CHANNEL - 1];
 312         }
 313
 314         n <<= (X38_DRB_SHIFT - PAGE_SHIFT);
 315         return n;
 316 }
 317
 318 static int x38_probe1(struct pci_dev *pdev, int dev_idx)
 319 {
 320         int rc;
 321         int i, j;
 322         struct mem_ctl_info *mci = NULL;
 323         struct edac_mc_layer layers[2];
 324         u16 drbs[X38_CHANNELS][X38_RANKS_PER_CHANNEL];
 325         bool stacked;
 326         void __iomem *window;
 327
 328         edac_dbg(0, "MC:\n");
 329
 330         window = x38_map_mchbar(pdev);
 331         if (!window)
 332                 return -ENODEV;
 333
 334         x38_get_drbs(window, drbs);
 335
 336         how_many_channel(pdev);
 337
 338         /* FIXME: unconventional pvt_info usage */
 339         layers[0].type = EDAC_MC_LAYER_CHIP_SELECT;
 340         layers[0].size = X38_RANKS;
 341         layers[0].is_virt_csrow = true;
 342         layers[1].type = EDAC_MC_LAYER_CHANNEL;
 343         layers[1].size = x38_channel_num;
 344         layers[1].is_virt_csrow = false;
 345         mci = edac_mc_alloc(0, ARRAY_SIZE(layers), layers, 0);
 346         if (!mci)
 347                 return -ENOMEM;
 348
 349         edac_dbg(3, "MC: init mci\n");
 350
 351         mci->pdev = &pdev->dev;
 352         mci->mtype_cap = MEM_FLAG_DDR2;
 353
 354         mci->edac_ctl_cap = EDAC_FLAG_SECDED;
 355         mci->edac_cap = EDAC_FLAG_SECDED;
 356
 357         mci->mod_name = EDAC_MOD_STR;
 358         mci->ctl_name = x38_devs[dev_idx].ctl_name;
 359         mci->dev_name = pci_name(pdev);
 360         mci->edac_check = x38_check;
 361         mci->ctl_page_to_phys = NULL;
 362         mci->pvt_info = window;
 363
 364         stacked = x38_is_stacked(pdev, drbs);
 365
 366         /*
 367          * The dram rank boundary (DRB) reg values are boundary addresses
 368          * for each DRAM rank with a granularity of 64MB.  DRB regs are
 369          * cumulative; the last one will contain the total memory
 370          * contained in all ranks.
 371          */
 372         for (i = 0; i < mci->nr_csrows; i++) {
 373                 unsigned long nr_pages;
 374                 struct csrow_info *csrow = mci->csrows[i];
 375
 376                 nr_pages = drb_to_nr_pages(drbs, stacked,
 377                         i / X38_RANKS_PER_CHANNEL,
 378                         i % X38_RANKS_PER_CHANNEL);
 379
 380                 if (nr_pages == 0)
 381                         continue;
 382
 383                 for (j = 0; j < x38_channel_num; j++) {
 384                         struct dimm_info *dimm = csrow->channels[j]->dimm;
 385
 386                         dimm->nr_pages = nr_pages / x38_channel_num;
 387                         dimm->grain = nr_pages << PAGE_SHIFT;
 388                         dimm->mtype = MEM_DDR2;
 389                         dimm->dtype = DEV_UNKNOWN;
 390                         dimm->edac_mode = EDAC_UNKNOWN;
 391                 }
 392         }
 393
 394         x38_clear_error_info(mci);
 395
 396         rc = -ENODEV;
 397         if (edac_mc_add_mc(mci)) {
 398                 edac_dbg(3, "MC: failed edac_mc_add_mc()\n");
 399                 goto fail;
 400         }
 401
 402         /* get this far and it's successful */
 403         edac_dbg(3, "MC: success\n");
 404         return 0;
 405
 406 fail:
 407         iounmap(window);
 408         if (mci)
 409                 edac_mc_free(mci);
 410
 411         return rc;
 412 }
 413
 414 static int x38_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 415 {
 416         int rc;
 417
 418         edac_dbg(0, "MC:\n");
 419
 420         if (pci_enable_device(pdev) < 0)
 421                 return -EIO;
 422
 423         rc = x38_probe1(pdev, ent->driver_data);
 424         if (!mci_pdev)
 425                 mci_pdev = pci_dev_get(pdev);
 426
 427         return rc;
 428 }
 429
 430 static void x38_remove_one(struct pci_dev *pdev)
 431 {
 432         struct mem_ctl_info *mci;
 433
 434         edac_dbg(0, "\n");
 435
 436         mci = edac_mc_del_mc(&pdev->dev);
 437         if (!mci)
 438                 return;
 439
 440         iounmap(mci->pvt_info);
 441
 442         edac_mc_free(mci);
 443 }
 444
 445 static const struct pci_device_id x38_pci_tbl[] = {
 446         {
 447          PCI_VEND_DEV(INTEL, X38_HB), PCI_ANY_ID, PCI_ANY_ID, 0, 0,
 448          X38},
 449         {
 450          0,
 451          }                      /* 0 terminated list. */
 452 };
 453
 454 MODULE_DEVICE_TABLE(pci, x38_pci_tbl);
 455
 456 static struct pci_driver x38_driver = {
 457         .name = EDAC_MOD_STR,
 458         .probe = x38_init_one,
 459         .remove = x38_remove_one,
 460         .id_table = x38_pci_tbl,
 461 };
 462
 463 static int __init x38_init(void)
 464 {
 465         int pci_rc;
 466
 467         edac_dbg(3, "MC:\n");
 468
 469         /* Ensure that the OPSTATE is set correctly for POLL or NMI */
 470         opstate_init();
 471
 472         pci_rc = pci_register_driver(&x38_driver);
 473         if (pci_rc < 0)
 474                 goto fail0;
 475
 476         if (!mci_pdev) {
 477                 x38_registered = 0;
 478                 mci_pdev = pci_get_device(PCI_VENDOR_ID_INTEL,
 479                                         PCI_DEVICE_ID_INTEL_X38_HB, NULL);
 480                 if (!mci_pdev) {
 481                         edac_dbg(0, "x38 pci_get_device fail\n");
 482                         pci_rc = -ENODEV;
 483                         goto fail1;
 484                 }
 485
 486                 pci_rc = x38_init_one(mci_pdev, x38_pci_tbl);
 487                 if (pci_rc < 0) {
 488                         edac_dbg(0, "x38 init fail\n");
 489                         pci_rc = -ENODEV;
 490                         goto fail1;
 491                 }
 492         }
 493
 494         return 0;
 495
 496 fail1:
 497         pci_unregister_driver(&x38_driver);
 498
 499 fail0:
 500         pci_dev_put(mci_pdev);
 501
 502         return pci_rc;
 503 }
 504
 505 static void __exit x38_exit(void)
 506 {
 507         edac_dbg(3, "MC:\n");
 508
 509         pci_unregister_driver(&x38_driver);
 510         if (!x38_registered) {
 511                 x38_remove_one(mci_pdev);
 512                 pci_dev_put(mci_pdev);
 513         }
 514 }
 515
 516 module_init(x38_init);
 517 module_exit(x38_exit);
 518
 519 MODULE_LICENSE("GPL");
 520 MODULE_AUTHOR("Cluster Computing, Inc. Hitoshi Mitake");
 521 MODULE_DESCRIPTION("MC support for Intel X38 memory hub controllers");
 522
 523 module_param(edac_op_state, int, 0444);
 524 MODULE_PARM_DESC(edac_op_state, "EDAC Error Reporting state: 0=Poll,1=NMI");