drivers/edac/i82443bxgx_edac.c

   1 /*
   2  * Intel 82443BX/GX (440BX/GX chipset) Memory Controller EDAC kernel
   3  * module (C) 2006 Tim Small
   4  *
   5  * This file may be distributed under the terms of the GNU General
   6  * Public License.
   7  *
   8  * Written by Tim Small <tim@buttersideup.com>, based on work by Linux
   9  * Networx, Thayne Harbaugh, Dan Hollis <goemon at anime dot net> and
  10  * others.
  11  *
  12  * 440GX fix by Jason Uhlenkott <juhlenko@akamai.com>.
  13  *
  14  * Written with reference to 82443BX Host Bridge Datasheet:
  15  * http://download.intel.com/design/chipsets/datashts/29063301.pdf
  16  * references to this document given in [].
  17  *
  18  * This module doesn't support the 440LX, but it may be possible to
  19  * make it do so (the 440LX's register definitions are different, but
  20  * not completely so - I haven't studied them in enough detail to know
  21  * how easy this would be).
  22  */
  23
  24 #include <linux/module.h>
  25 #include <linux/init.h>
  26
  27 #include <linux/pci.h>
  28 #include <linux/pci_ids.h>
  29
  30
  31 #include <linux/edac.h>
  32 #include "edac_core.h"
  33
  34 #define I82443_REVISION "0.1"
  35
  36 #define EDAC_MOD_STR    "i82443bxgx_edac"
  37
  38 /* The 82443BX supports SDRAM, or EDO (EDO for mobile only), "Memory
  39  * Size: 8 MB to 512 MB (1GB with Registered DIMMs) with eight memory
  40  * rows" "The 82443BX supports multiple-bit error detection and
  41  * single-bit error correction when ECC mode is enabled and
  42  * single/multi-bit error detection when correction is disabled.
  43  * During writes to the DRAM, the 82443BX generates ECC for the data
  44  * on a QWord basis. Partial QWord writes require a read-modify-write
  45  * cycle when ECC is enabled."
  46 */
  47
  48 /* "Additionally, the 82443BX ensures that the data is corrected in
  49  * main memory so that accumulation of errors is prevented. Another
  50  * error within the same QWord would result in a double-bit error
  51  * which is unrecoverable. This is known as hardware scrubbing since
  52  * it requires no software intervention to correct the data in memory."
  53  */
  54
  55 /* [Also see page 100 (section 4.3), "DRAM Interface"]
  56  * [Also see page 112 (section 4.6.1.4), ECC]
  57  */
  58
  59 #define I82443BXGX_NR_CSROWS 8
  60 #define I82443BXGX_NR_CHANS  1
  61 #define I82443BXGX_NR_DIMMS  4
  62
  63 /* 82443 PCI Device 0 */
  64 #define I82443BXGX_NBXCFG 0x50  /* 32bit register starting at this PCI
  65                                  * config space offset */
  66 #define I82443BXGX_NBXCFG_OFFSET_NON_ECCROW 24  /* Array of bits, zero if
  67                                                  * row is non-ECC */
  68 #define I82443BXGX_NBXCFG_OFFSET_DRAM_FREQ 12   /* 2 bits,00=100MHz,10=66 MHz */
  69
  70 #define I82443BXGX_NBXCFG_OFFSET_DRAM_INTEGRITY 7       /* 2 bits:       */
  71 #define I82443BXGX_NBXCFG_INTEGRITY_NONE   0x0  /* 00 = Non-ECC */
  72 #define I82443BXGX_NBXCFG_INTEGRITY_EC     0x1  /* 01 = EC (only) */
  73 #define I82443BXGX_NBXCFG_INTEGRITY_ECC    0x2  /* 10 = ECC */
  74 #define I82443BXGX_NBXCFG_INTEGRITY_SCRUB  0x3  /* 11 = ECC + HW Scrub */
  75
  76 #define I82443BXGX_NBXCFG_OFFSET_ECC_DIAG_ENABLE  6
  77
  78 /* 82443 PCI Device 0 */
  79 #define I82443BXGX_EAP   0x80   /* 32bit register starting at this PCI
  80                                  * config space offset, Error Address
  81                                  * Pointer Register */
  82 #define I82443BXGX_EAP_OFFSET_EAP  12   /* High 20 bits of error address */
  83 #define I82443BXGX_EAP_OFFSET_MBE  BIT(1)       /* Err at EAP was multi-bit (W1TC) */
  84 #define I82443BXGX_EAP_OFFSET_SBE  BIT(0)       /* Err at EAP was single-bit (W1TC) */
  85
  86 #define I82443BXGX_ERRCMD  0x90 /* 8bit register starting at this PCI
  87                                  * config space offset. */
  88 #define I82443BXGX_ERRCMD_OFFSET_SERR_ON_MBE BIT(1)     /* 1 = enable */
  89 #define I82443BXGX_ERRCMD_OFFSET_SERR_ON_SBE BIT(0)     /* 1 = enable */
  90
  91 #define I82443BXGX_ERRSTS  0x91 /* 16bit register starting at this PCI
  92                                  * config space offset. */
  93 #define I82443BXGX_ERRSTS_OFFSET_MBFRE 5        /* 3 bits - first err row multibit */
  94 #define I82443BXGX_ERRSTS_OFFSET_MEF   BIT(4)   /* 1 = MBE occurred */
  95 #define I82443BXGX_ERRSTS_OFFSET_SBFRE 1        /* 3 bits - first err row singlebit */
  96 #define I82443BXGX_ERRSTS_OFFSET_SEF   BIT(0)   /* 1 = SBE occurred */
  97
  98 #define I82443BXGX_DRAMC 0x57   /* 8bit register starting at this PCI
  99                                  * config space offset. */
 100 #define I82443BXGX_DRAMC_OFFSET_DT 3    /* 2 bits, DRAM Type */
 101 #define I82443BXGX_DRAMC_DRAM_IS_EDO 0  /* 00 = EDO */
 102 #define I82443BXGX_DRAMC_DRAM_IS_SDRAM 1        /* 01 = SDRAM */
 103 #define I82443BXGX_DRAMC_DRAM_IS_RSDRAM 2       /* 10 = Registered SDRAM */
 104
 105 #define I82443BXGX_DRB 0x60     /* 8x 8bit registers starting at this PCI
 106                                  * config space offset. */
 107
 108 /* FIXME - don't poll when ECC disabled? */
 109
 110 struct i82443bxgx_edacmc_error_info {
 111         u32 eap;
 112 };
 113
 114 static struct edac_pci_ctl_info *i82443bxgx_pci;
 115
 116 static struct pci_dev *mci_pdev;        /* init dev: in case that AGP code has
 117                                          * already registered driver
 118                                          */
 119
 120 static int i82443bxgx_registered = 1;
 121
 122 static void i82443bxgx_edacmc_get_error_info(struct mem_ctl_info *mci,
 123                                 struct i82443bxgx_edacmc_error_info
 124                                 *info)
 125 {
 126         struct pci_dev *pdev;
 127         pdev = to_pci_dev(mci->pdev);
 128         pci_read_config_dword(pdev, I82443BXGX_EAP, &info->eap);
 129         if (info->eap & I82443BXGX_EAP_OFFSET_SBE)
 130                 /* Clear error to allow next error to be reported [p.61] */
 131                 pci_write_bits32(pdev, I82443BXGX_EAP,
 132                                  I82443BXGX_EAP_OFFSET_SBE,
 133                                  I82443BXGX_EAP_OFFSET_SBE);
 134
 135         if (info->eap & I82443BXGX_EAP_OFFSET_MBE)
 136                 /* Clear error to allow next error to be reported [p.61] */
 137                 pci_write_bits32(pdev, I82443BXGX_EAP,
 138                                  I82443BXGX_EAP_OFFSET_MBE,
 139                                  I82443BXGX_EAP_OFFSET_MBE);
 140 }
 141
 142 static int i82443bxgx_edacmc_process_error_info(struct mem_ctl_info *mci,
 143                                                 struct
 144                                                 i82443bxgx_edacmc_error_info
 145                                                 *info, int handle_errors)
 146 {
 147         int error_found = 0;
 148         u32 eapaddr, page, pageoffset;
 149
 150         /* bits 30:12 hold the 4kb block in which the error occurred
 151          * [p.61] */
 152         eapaddr = (info->eap & 0xfffff000);
 153         page = eapaddr >> PAGE_SHIFT;
 154         pageoffset = eapaddr - (page << PAGE_SHIFT);
 155
 156         if (info->eap & I82443BXGX_EAP_OFFSET_SBE) {
 157                 error_found = 1;
 158                 if (handle_errors)
 159                         edac_mc_handle_error(HW_EVENT_ERR_CORRECTED, mci, 1,
 160                                              page, pageoffset, 0,
 161                                              edac_mc_find_csrow_by_page(mci, page),
 162                                              0, -1, mci->ctl_name, "");
 163         }
 164
 165         if (info->eap & I82443BXGX_EAP_OFFSET_MBE) {
 166                 error_found = 1;
 167                 if (handle_errors)
 168                         edac_mc_handle_error(HW_EVENT_ERR_UNCORRECTED, mci, 1,
 169                                              page, pageoffset, 0,
 170                                              edac_mc_find_csrow_by_page(mci, page),
 171                                              0, -1, mci->ctl_name, "");
 172         }
 173
 174         return error_found;
 175 }
 176
 177 static void i82443bxgx_edacmc_check(struct mem_ctl_info *mci)
 178 {
 179         struct i82443bxgx_edacmc_error_info info;
 180
 181         edac_dbg(1, "MC%d\n", mci->mc_idx);
 182         i82443bxgx_edacmc_get_error_info(mci, &info);
 183         i82443bxgx_edacmc_process_error_info(mci, &info, 1);
 184 }
 185
 186 static void i82443bxgx_init_csrows(struct mem_ctl_info *mci,
 187                                 struct pci_dev *pdev,
 188                                 enum edac_type edac_mode,
 189                                 enum mem_type mtype)
 190 {
 191         struct csrow_info *csrow;
 192         struct dimm_info *dimm;
 193         int index;
 194         u8 drbar, dramc;
 195         u32 row_base, row_high_limit, row_high_limit_last;
 196
 197         pci_read_config_byte(pdev, I82443BXGX_DRAMC, &dramc);
 198         row_high_limit_last = 0;
 199         for (index = 0; index < mci->nr_csrows; index++) {
 200                 csrow = mci->csrows[index];
 201                 dimm = csrow->channels[0]->dimm;
 202
 203                 pci_read_config_byte(pdev, I82443BXGX_DRB + index, &drbar);
 204                 edac_dbg(1, "MC%d: Row=%d DRB = %#0x\n",
 205                          mci->mc_idx, index, drbar);
 206                 row_high_limit = ((u32) drbar << 23);
 207                 /* find the DRAM Chip Select Base address and mask */
 208                 edac_dbg(1, "MC%d: Row=%d, Boundary Address=%#0x, Last = %#0x\n",
 209                          mci->mc_idx, index, row_high_limit,
 210                          row_high_limit_last);
 211
 212                 /* 440GX goes to 2GB, represented with a DRB of 0. */
 213                 if (row_high_limit_last && !row_high_limit)
 214                         row_high_limit = 1UL << 31;
 215
 216                 /* This row is empty [p.49] */
 217                 if (row_high_limit == row_high_limit_last)
 218                         continue;
 219                 row_base = row_high_limit_last;
 220                 csrow->first_page = row_base >> PAGE_SHIFT;
 221                 csrow->last_page = (row_high_limit >> PAGE_SHIFT) - 1;
 222                 dimm->nr_pages = csrow->last_page - csrow->first_page + 1;
 223                 /* EAP reports in 4kilobyte granularity [61] */
 224                 dimm->grain = 1 << 12;
 225                 dimm->mtype = mtype;
 226                 /* I don't think 440BX can tell you device type? FIXME? */
 227                 dimm->dtype = DEV_UNKNOWN;
 228                 /* Mode is global to all rows on 440BX */
 229                 dimm->edac_mode = edac_mode;
 230                 row_high_limit_last = row_high_limit;
 231         }
 232 }
 233
 234 static int i82443bxgx_edacmc_probe1(struct pci_dev *pdev, int dev_idx)
 235 {
 236         struct mem_ctl_info *mci;
 237         struct edac_mc_layer layers[2];
 238         u8 dramc;
 239         u32 nbxcfg, ecc_mode;
 240         enum mem_type mtype;
 241         enum edac_type edac_mode;
 242
 243         edac_dbg(0, "MC:\n");
 244
 245         /* Something is really hosed if PCI config space reads from
 246          * the MC aren't working.
 247          */
 248         if (pci_read_config_dword(pdev, I82443BXGX_NBXCFG, &nbxcfg))
 249                 return -EIO;
 250
 251         layers[0].type = EDAC_MC_LAYER_CHIP_SELECT;
 252         layers[0].size = I82443BXGX_NR_CSROWS;
 253         layers[0].is_virt_csrow = true;
 254         layers[1].type = EDAC_MC_LAYER_CHANNEL;
 255         layers[1].size = I82443BXGX_NR_CHANS;
 256         layers[1].is_virt_csrow = false;
 257         mci = edac_mc_alloc(0, ARRAY_SIZE(layers), layers, 0);
 258         if (mci == NULL)
 259                 return -ENOMEM;
 260
 261         edac_dbg(0, "MC: mci = %p\n", mci);
 262         mci->pdev = &pdev->dev;
 263         mci->mtype_cap = MEM_FLAG_EDO | MEM_FLAG_SDR | MEM_FLAG_RDR;
 264         mci->edac_ctl_cap = EDAC_FLAG_NONE | EDAC_FLAG_EC | EDAC_FLAG_SECDED;
 265         pci_read_config_byte(pdev, I82443BXGX_DRAMC, &dramc);
 266         switch ((dramc >> I82443BXGX_DRAMC_OFFSET_DT) & (BIT(0) | BIT(1))) {
 267         case I82443BXGX_DRAMC_DRAM_IS_EDO:
 268                 mtype = MEM_EDO;
 269                 break;
 270         case I82443BXGX_DRAMC_DRAM_IS_SDRAM:
 271                 mtype = MEM_SDR;
 272                 break;
 273         case I82443BXGX_DRAMC_DRAM_IS_RSDRAM:
 274                 mtype = MEM_RDR;
 275                 break;
 276         default:
 277                 edac_dbg(0, "Unknown/reserved DRAM type value in DRAMC register!\n");
 278                 mtype = -MEM_UNKNOWN;
 279         }
 280
 281         if ((mtype == MEM_SDR) || (mtype == MEM_RDR))
 282                 mci->edac_cap = mci->edac_ctl_cap;
 283         else
 284                 mci->edac_cap = EDAC_FLAG_NONE;
 285
 286         mci->scrub_cap = SCRUB_FLAG_HW_SRC;
 287         pci_read_config_dword(pdev, I82443BXGX_NBXCFG, &nbxcfg);
 288         ecc_mode = ((nbxcfg >> I82443BXGX_NBXCFG_OFFSET_DRAM_INTEGRITY) &
 289                 (BIT(0) | BIT(1)));
 290
 291         mci->scrub_mode = (ecc_mode == I82443BXGX_NBXCFG_INTEGRITY_SCRUB)
 292                 ? SCRUB_HW_SRC : SCRUB_NONE;
 293
 294         switch (ecc_mode) {
 295         case I82443BXGX_NBXCFG_INTEGRITY_NONE:
 296                 edac_mode = EDAC_NONE;
 297                 break;
 298         case I82443BXGX_NBXCFG_INTEGRITY_EC:
 299                 edac_mode = EDAC_EC;
 300                 break;
 301         case I82443BXGX_NBXCFG_INTEGRITY_ECC:
 302         case I82443BXGX_NBXCFG_INTEGRITY_SCRUB:
 303                 edac_mode = EDAC_SECDED;
 304                 break;
 305         default:
 306                 edac_dbg(0, "Unknown/reserved ECC state in NBXCFG register!\n");
 307                 edac_mode = EDAC_UNKNOWN;
 308                 break;
 309         }
 310
 311         i82443bxgx_init_csrows(mci, pdev, edac_mode, mtype);
 312
 313         /* Many BIOSes don't clear error flags on boot, so do this
 314          * here, or we get "phantom" errors occurring at module-load
 315          * time. */
 316         pci_write_bits32(pdev, I82443BXGX_EAP,
 317                         (I82443BXGX_EAP_OFFSET_SBE |
 318                                 I82443BXGX_EAP_OFFSET_MBE),
 319                         (I82443BXGX_EAP_OFFSET_SBE |
 320                                 I82443BXGX_EAP_OFFSET_MBE));
 321
 322         mci->mod_name = EDAC_MOD_STR;
 323         mci->mod_ver = I82443_REVISION;
 324         mci->ctl_name = "I82443BXGX";
 325         mci->dev_name = pci_name(pdev);
 326         mci->edac_check = i82443bxgx_edacmc_check;
 327         mci->ctl_page_to_phys = NULL;
 328
 329         if (edac_mc_add_mc(mci)) {
 330                 edac_dbg(3, "failed edac_mc_add_mc()\n");
 331                 goto fail;
 332         }
 333
 334         /* allocating generic PCI control info */
 335         i82443bxgx_pci = edac_pci_create_generic_ctl(&pdev->dev, EDAC_MOD_STR);
 336         if (!i82443bxgx_pci) {
 337                 printk(KERN_WARNING
 338                         "%s(): Unable to create PCI control\n",
 339                         __func__);
 340                 printk(KERN_WARNING
 341                         "%s(): PCI error report via EDAC not setup\n",
 342                         __func__);
 343         }
 344
 345         edac_dbg(3, "MC: success\n");
 346         return 0;
 347
 348 fail:
 349         edac_mc_free(mci);
 350         return -ENODEV;
 351 }
 352
 353 EXPORT_SYMBOL_GPL(i82443bxgx_edacmc_probe1);
 354
 355 /* returns count (>= 0), or negative on error */
 356 static int i82443bxgx_edacmc_init_one(struct pci_dev *pdev,
 357                                       const struct pci_device_id *ent)
 358 {
 359         int rc;
 360
 361         edac_dbg(0, "MC:\n");
 362
 363         /* don't need to call pci_enable_device() */
 364         rc = i82443bxgx_edacmc_probe1(pdev, ent->driver_data);
 365
 366         if (mci_pdev == NULL)
 367                 mci_pdev = pci_dev_get(pdev);
 368
 369         return rc;
 370 }
 371
 372 static void i82443bxgx_edacmc_remove_one(struct pci_dev *pdev)
 373 {
 374         struct mem_ctl_info *mci;
 375
 376         edac_dbg(0, "\n");
 377
 378         if (i82443bxgx_pci)
 379                 edac_pci_release_generic_ctl(i82443bxgx_pci);
 380
 381         if ((mci = edac_mc_del_mc(&pdev->dev)) == NULL)
 382                 return;
 383
 384         edac_mc_free(mci);
 385 }
 386
 387 EXPORT_SYMBOL_GPL(i82443bxgx_edacmc_remove_one);
 388
 389 static DEFINE_PCI_DEVICE_TABLE(i82443bxgx_pci_tbl) = {
 390         {PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82443BX_0)},
 391         {PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82443BX_2)},
 392         {PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82443GX_0)},
 393         {PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82443GX_2)},
 394         {0,}                    /* 0 terminated list. */
 395 };
 396
 397 MODULE_DEVICE_TABLE(pci, i82443bxgx_pci_tbl);
 398
 399 static struct pci_driver i82443bxgx_edacmc_driver = {
 400         .name = EDAC_MOD_STR,
 401         .probe = i82443bxgx_edacmc_init_one,
 402         .remove = i82443bxgx_edacmc_remove_one,
 403         .id_table = i82443bxgx_pci_tbl,
 404 };
 405
 406 static int __init i82443bxgx_edacmc_init(void)
 407 {
 408         int pci_rc;
 409        /* Ensure that the OPSTATE is set correctly for POLL or NMI */
 410        opstate_init();
 411
 412         pci_rc = pci_register_driver(&i82443bxgx_edacmc_driver);
 413         if (pci_rc < 0)
 414                 goto fail0;
 415
 416         if (mci_pdev == NULL) {
 417                 const struct pci_device_id *id = &i82443bxgx_pci_tbl[0];
 418                 int i = 0;
 419                 i82443bxgx_registered = 0;
 420
 421                 while (mci_pdev == NULL && id->vendor != 0) {
 422                         mci_pdev = pci_get_device(id->vendor,
 423                                         id->device, NULL);
 424                         i++;
 425                         id = &i82443bxgx_pci_tbl[i];
 426                 }
 427                 if (!mci_pdev) {
 428                         edac_dbg(0, "i82443bxgx pci_get_device fail\n");
 429                         pci_rc = -ENODEV;
 430                         goto fail1;
 431                 }
 432
 433                 pci_rc = i82443bxgx_edacmc_init_one(mci_pdev, i82443bxgx_pci_tbl);
 434
 435                 if (pci_rc < 0) {
 436                         edac_dbg(0, "i82443bxgx init fail\n");
 437                         pci_rc = -ENODEV;
 438                         goto fail1;
 439                 }
 440         }
 441
 442         return 0;
 443
 444 fail1:
 445         pci_unregister_driver(&i82443bxgx_edacmc_driver);
 446
 447 fail0:
 448         if (mci_pdev != NULL)
 449                 pci_dev_put(mci_pdev);
 450
 451         return pci_rc;
 452 }
 453
 454 static void __exit i82443bxgx_edacmc_exit(void)
 455 {
 456         pci_unregister_driver(&i82443bxgx_edacmc_driver);
 457
 458         if (!i82443bxgx_registered)
 459                 i82443bxgx_edacmc_remove_one(mci_pdev);
 460
 461         if (mci_pdev)
 462                 pci_dev_put(mci_pdev);
 463 }
 464
 465 module_init(i82443bxgx_edacmc_init);
 466 module_exit(i82443bxgx_edacmc_exit);
 467
 468 MODULE_LICENSE("GPL");
 469 MODULE_AUTHOR("Tim Small <tim@buttersideup.com> - WPAD");
 470 MODULE_DESCRIPTION("EDAC MC support for Intel 82443BX/GX memory controllers");
 471
 472 module_param(edac_op_state, int, 0444);
 473 MODULE_PARM_DESC(edac_op_state, "EDAC Error Reporting state: 0=Poll,1=NMI");