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(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"); 525