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         x38_get_and_clear_error_info(mci, &info);
 242         x38_process_error_info(mci, &info);
 243 }
 244
 245 static void __iomem *x38_map_mchbar(struct pci_dev *pdev)
 246 {
 247         union {
 248                 u64 mchbar;
 249                 struct {
 250                         u32 mchbar_low;
 251                         u32 mchbar_high;
 252                 };
 253         } u;
 254         void __iomem *window;
 255
 256         pci_read_config_dword(pdev, X38_MCHBAR_LOW, &u.mchbar_low);
 257         pci_write_config_dword(pdev, X38_MCHBAR_LOW, u.mchbar_low | 0x1);
 258         pci_read_config_dword(pdev, X38_MCHBAR_HIGH, &u.mchbar_high);
 259         u.mchbar &= X38_MCHBAR_MASK;
 260
 261         if (u.mchbar != (resource_size_t)u.mchbar) {
 262                 printk(KERN_ERR
 263                         "x38: mmio space beyond accessible range (0x%llx)\n",
 264                         (unsigned long long)u.mchbar);
 265                 return NULL;
 266         }
 267
 268         window = ioremap(u.mchbar, X38_MMR_WINDOW_SIZE);
 269         if (!window)
 270                 printk(KERN_ERR "x38: cannot map mmio space at 0x%llx\n",
 271                         (unsigned long long)u.mchbar);
 272
 273         return window;
 274 }
 275
 276
 277 static void x38_get_drbs(void __iomem *window,
 278                         u16 drbs[X38_CHANNELS][X38_RANKS_PER_CHANNEL])
 279 {
 280         int i;
 281
 282         for (i = 0; i < X38_RANKS_PER_CHANNEL; i++) {
 283                 drbs[0][i] = readw(window + X38_C0DRB + 2*i) & X38_DRB_MASK;
 284                 drbs[1][i] = readw(window + X38_C1DRB + 2*i) & X38_DRB_MASK;
 285         }
 286 }
 287
 288 static bool x38_is_stacked(struct pci_dev *pdev,
 289                         u16 drbs[X38_CHANNELS][X38_RANKS_PER_CHANNEL])
 290 {
 291         u16 tom;
 292
 293         pci_read_config_word(pdev, X38_TOM, &tom);
 294         tom &= X38_TOM_MASK;
 295
 296         return drbs[X38_CHANNELS - 1][X38_RANKS_PER_CHANNEL - 1] == tom;
 297 }
 298
 299 static unsigned long drb_to_nr_pages(
 300                         u16 drbs[X38_CHANNELS][X38_RANKS_PER_CHANNEL],
 301                         bool stacked, int channel, int rank)
 302 {
 303         int n;
 304
 305         n = drbs[channel][rank];
 306         if (rank > 0)
 307                 n -= drbs[channel][rank - 1];
 308         if (stacked && (channel == 1) && drbs[channel][rank] ==
 309                                 drbs[channel][X38_RANKS_PER_CHANNEL - 1]) {
 310                 n -= drbs[0][X38_RANKS_PER_CHANNEL - 1];
 311         }
 312
 313         n <<= (X38_DRB_SHIFT - PAGE_SHIFT);
 314         return n;
 315 }
 316
 317 static int x38_probe1(struct pci_dev *pdev, int dev_idx)
 318 {
 319         int rc;
 320         int i, j;
 321         struct mem_ctl_info *mci = NULL;
 322         struct edac_mc_layer layers[2];
 323         u16 drbs[X38_CHANNELS][X38_RANKS_PER_CHANNEL];
 324         bool stacked;
 325         void __iomem *window;
 326
 327         edac_dbg(0, "MC:\n");
 328
 329         window = x38_map_mchbar(pdev);
 330         if (!window)
 331                 return -ENODEV;
 332
 333         x38_get_drbs(window, drbs);
 334
 335         how_many_channel(pdev);
 336
 337         /* FIXME: unconventional pvt_info usage */
 338         layers[0].type = EDAC_MC_LAYER_CHIP_SELECT;
 339         layers[0].size = X38_RANKS;
 340         layers[0].is_virt_csrow = true;
 341         layers[1].type = EDAC_MC_LAYER_CHANNEL;
 342         layers[1].size = x38_channel_num;
 343         layers[1].is_virt_csrow = false;
 344         mci = edac_mc_alloc(0, ARRAY_SIZE(layers), layers, 0);
 345         if (!mci)
 346                 return -ENOMEM;
 347
 348         edac_dbg(3, "MC: init mci\n");
 349
 350         mci->pdev = &pdev->dev;
 351         mci->mtype_cap = MEM_FLAG_DDR2;
 352
 353         mci->edac_ctl_cap = EDAC_FLAG_SECDED;
 354         mci->edac_cap = EDAC_FLAG_SECDED;
 355
 356         mci->mod_name = EDAC_MOD_STR;
 357         mci->ctl_name = x38_devs[dev_idx].ctl_name;
 358         mci->dev_name = pci_name(pdev);
 359         mci->edac_check = x38_check;
 360         mci->ctl_page_to_phys = NULL;
 361         mci->pvt_info = window;
 362
 363         stacked = x38_is_stacked(pdev, drbs);
 364
 365         /*
 366          * The dram rank boundary (DRB) reg values are boundary addresses
 367          * for each DRAM rank with a granularity of 64MB.  DRB regs are
 368          * cumulative; the last one will contain the total memory
 369          * contained in all ranks.
 370          */
 371         for (i = 0; i < mci->nr_csrows; i++) {
 372                 unsigned long nr_pages;
 373                 struct csrow_info *csrow = mci->csrows[i];
 374
 375                 nr_pages = drb_to_nr_pages(drbs, stacked,
 376                         i / X38_RANKS_PER_CHANNEL,
 377                         i % X38_RANKS_PER_CHANNEL);
 378
 379                 if (nr_pages == 0)
 380                         continue;
 381
 382                 for (j = 0; j < x38_channel_num; j++) {
 383                         struct dimm_info *dimm = csrow->channels[j]->dimm;
 384
 385                         dimm->nr_pages = nr_pages / x38_channel_num;
 386                         dimm->grain = nr_pages << PAGE_SHIFT;
 387                         dimm->mtype = MEM_DDR2;
 388                         dimm->dtype = DEV_UNKNOWN;
 389                         dimm->edac_mode = EDAC_UNKNOWN;
 390                 }
 391         }
 392
 393         x38_clear_error_info(mci);
 394
 395         rc = -ENODEV;
 396         if (edac_mc_add_mc(mci)) {
 397                 edac_dbg(3, "MC: failed edac_mc_add_mc()\n");
 398                 goto fail;
 399         }
 400
 401         /* get this far and it's successful */
 402         edac_dbg(3, "MC: success\n");
 403         return 0;
 404
 405 fail:
 406         iounmap(window);
 407         if (mci)
 408                 edac_mc_free(mci);
 409
 410         return rc;
 411 }
 412
 413 static int x38_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 414 {
 415         int rc;
 416
 417         edac_dbg(0, "MC:\n");
 418
 419         if (pci_enable_device(pdev) < 0)
 420                 return -EIO;
 421
 422         rc = x38_probe1(pdev, ent->driver_data);
 423         if (!mci_pdev)
 424                 mci_pdev = pci_dev_get(pdev);
 425
 426         return rc;
 427 }
 428
 429 static void x38_remove_one(struct pci_dev *pdev)
 430 {
 431         struct mem_ctl_info *mci;
 432
 433         edac_dbg(0, "\n");
 434
 435         mci = edac_mc_del_mc(&pdev->dev);
 436         if (!mci)
 437                 return;
 438
 439         iounmap(mci->pvt_info);
 440
 441         edac_mc_free(mci);
 442 }
 443
 444 static const struct pci_device_id x38_pci_tbl[] = {
 445         {
 446          PCI_VEND_DEV(INTEL, X38_HB), PCI_ANY_ID, PCI_ANY_ID, 0, 0,
 447          X38},
 448         {
 449          0,
 450          }                      /* 0 terminated list. */
 451 };
 452
 453 MODULE_DEVICE_TABLE(pci, x38_pci_tbl);
 454
 455 static struct pci_driver x38_driver = {
 456         .name = EDAC_MOD_STR,
 457         .probe = x38_init_one,
 458         .remove = x38_remove_one,
 459         .id_table = x38_pci_tbl,
 460 };
 461
 462 static int __init x38_init(void)
 463 {
 464         int pci_rc;
 465
 466         edac_dbg(3, "MC:\n");
 467
 468         /* Ensure that the OPSTATE is set correctly for POLL or NMI */
 469         opstate_init();
 470
 471         pci_rc = pci_register_driver(&x38_driver);
 472         if (pci_rc < 0)
 473                 goto fail0;
 474
 475         if (!mci_pdev) {
 476                 x38_registered = 0;
 477                 mci_pdev = pci_get_device(PCI_VENDOR_ID_INTEL,
 478                                         PCI_DEVICE_ID_INTEL_X38_HB, NULL);
 479                 if (!mci_pdev) {
 480                         edac_dbg(0, "x38 pci_get_device fail\n");
 481                         pci_rc = -ENODEV;
 482                         goto fail1;
 483                 }
 484
 485                 pci_rc = x38_init_one(mci_pdev, x38_pci_tbl);
 486                 if (pci_rc < 0) {
 487                         edac_dbg(0, "x38 init fail\n");
 488                         pci_rc = -ENODEV;
 489                         goto fail1;
 490                 }
 491         }
 492
 493         return 0;
 494
 495 fail1:
 496         pci_unregister_driver(&x38_driver);
 497
 498 fail0:
 499         pci_dev_put(mci_pdev);
 500
 501         return pci_rc;
 502 }
 503
 504 static void __exit x38_exit(void)
 505 {
 506         edac_dbg(3, "MC:\n");
 507
 508         pci_unregister_driver(&x38_driver);
 509         if (!x38_registered) {
 510                 x38_remove_one(mci_pdev);
 511                 pci_dev_put(mci_pdev);
 512         }
 513 }
 514
 515 module_init(x38_init);
 516 module_exit(x38_exit);
 517
 518 MODULE_LICENSE("GPL");
 519 MODULE_AUTHOR("Cluster Computing, Inc. Hitoshi Mitake");
 520 MODULE_DESCRIPTION("MC support for Intel X38 memory hub controllers");
 521
 522 module_param(edac_op_state, int, 0444);
 523 MODULE_PARM_DESC(edac_op_state, "EDAC Error Reporting state: 0=Poll,1=NMI");