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 #include "edac_core.h" 18 19 #define X38_REVISION "1.1" 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 debugf0("In single channel mode.\n"); 107 x38_channel_num = 1; 108 } else { 109 debugf0("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->dev); 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 u64 x38_readq(const void __iomem *addr) 165 { 166 return readl(addr) | (((u64)readl(addr + 4)) << 32); 167 } 168 169 static void x38_get_and_clear_error_info(struct mem_ctl_info *mci, 170 struct x38_error_info *info) 171 { 172 struct pci_dev *pdev; 173 void __iomem *window = mci->pvt_info; 174 175 pdev = to_pci_dev(mci->dev); 176 177 /* 178 * This is a mess because there is no atomic way to read all the 179 * registers at once and the registers can transition from CE being 180 * overwritten by UE. 181 */ 182 pci_read_config_word(pdev, X38_ERRSTS, &info->errsts); 183 if (!(info->errsts & X38_ERRSTS_BITS)) 184 return; 185 186 info->eccerrlog[0] = x38_readq(window + X38_C0ECCERRLOG); 187 if (x38_channel_num == 2) 188 info->eccerrlog[1] = x38_readq(window + X38_C1ECCERRLOG); 189 190 pci_read_config_word(pdev, X38_ERRSTS, &info->errsts2); 191 192 /* 193 * If the error is the same for both reads then the first set 194 * of reads is valid. If there is a change then there is a CE 195 * with no info and the second set of reads is valid and 196 * should be UE info. 197 */ 198 if ((info->errsts ^ info->errsts2) & X38_ERRSTS_BITS) { 199 info->eccerrlog[0] = x38_readq(window + X38_C0ECCERRLOG); 200 if (x38_channel_num == 2) 201 info->eccerrlog[1] = 202 x38_readq(window + X38_C1ECCERRLOG); 203 } 204 205 x38_clear_error_info(mci); 206 } 207 208 static void x38_process_error_info(struct mem_ctl_info *mci, 209 struct x38_error_info *info) 210 { 211 int channel; 212 u64 log; 213 214 if (!(info->errsts & X38_ERRSTS_BITS)) 215 return; 216 217 if ((info->errsts ^ info->errsts2) & X38_ERRSTS_BITS) { 218 edac_mc_handle_ce_no_info(mci, "UE overwrote CE"); 219 info->errsts = info->errsts2; 220 } 221 222 for (channel = 0; channel < x38_channel_num; channel++) { 223 log = info->eccerrlog[channel]; 224 if (log & X38_ECCERRLOG_UE) { 225 edac_mc_handle_ue(mci, 0, 0, 226 eccerrlog_row(channel, log), "x38 UE"); 227 } else if (log & X38_ECCERRLOG_CE) { 228 edac_mc_handle_ce(mci, 0, 0, 229 eccerrlog_syndrome(log), 230 eccerrlog_row(channel, log), 0, "x38 CE"); 231 } 232 } 233 } 234 235 static void x38_check(struct mem_ctl_info *mci) 236 { 237 struct x38_error_info info; 238 239 debugf1("MC%d: %s()\n", mci->mc_idx, __func__); 240 x38_get_and_clear_error_info(mci, &info); 241 x38_process_error_info(mci, &info); 242 } 243 244 245 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_nocache(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; 321 struct mem_ctl_info *mci = NULL; 322 unsigned long last_page; 323 u16 drbs[X38_CHANNELS][X38_RANKS_PER_CHANNEL]; 324 bool stacked; 325 void __iomem *window; 326 327 debugf0("MC: %s()\n", __func__); 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 mci = edac_mc_alloc(0, X38_RANKS, x38_channel_num, 0); 339 if (!mci) 340 return -ENOMEM; 341 342 debugf3("MC: %s(): init mci\n", __func__); 343 344 mci->dev = &pdev->dev; 345 mci->mtype_cap = MEM_FLAG_DDR2; 346 347 mci->edac_ctl_cap = EDAC_FLAG_SECDED; 348 mci->edac_cap = EDAC_FLAG_SECDED; 349 350 mci->mod_name = EDAC_MOD_STR; 351 mci->mod_ver = X38_REVISION; 352 mci->ctl_name = x38_devs[dev_idx].ctl_name; 353 mci->dev_name = pci_name(pdev); 354 mci->edac_check = x38_check; 355 mci->ctl_page_to_phys = NULL; 356 mci->pvt_info = window; 357 358 stacked = x38_is_stacked(pdev, drbs); 359 360 /* 361 * The dram rank boundary (DRB) reg values are boundary addresses 362 * for each DRAM rank with a granularity of 64MB. DRB regs are 363 * cumulative; the last one will contain the total memory 364 * contained in all ranks. 365 */ 366 last_page = -1UL; 367 for (i = 0; i < mci->nr_csrows; i++) { 368 unsigned long nr_pages; 369 struct csrow_info *csrow = &mci->csrows[i]; 370 371 nr_pages = drb_to_nr_pages(drbs, stacked, 372 i / X38_RANKS_PER_CHANNEL, 373 i % X38_RANKS_PER_CHANNEL); 374 375 if (nr_pages == 0) { 376 csrow->mtype = MEM_EMPTY; 377 continue; 378 } 379 380 csrow->first_page = last_page + 1; 381 last_page += nr_pages; 382 csrow->last_page = last_page; 383 csrow->nr_pages = nr_pages; 384 385 csrow->grain = nr_pages << PAGE_SHIFT; 386 csrow->mtype = MEM_DDR2; 387 csrow->dtype = DEV_UNKNOWN; 388 csrow->edac_mode = EDAC_UNKNOWN; 389 } 390 391 x38_clear_error_info(mci); 392 393 rc = -ENODEV; 394 if (edac_mc_add_mc(mci)) { 395 debugf3("MC: %s(): failed edac_mc_add_mc()\n", __func__); 396 goto fail; 397 } 398 399 /* get this far and it's successful */ 400 debugf3("MC: %s(): success\n", __func__); 401 return 0; 402 403 fail: 404 iounmap(window); 405 if (mci) 406 edac_mc_free(mci); 407 408 return rc; 409 } 410 411 static int __devinit x38_init_one(struct pci_dev *pdev, 412 const struct pci_device_id *ent) 413 { 414 int rc; 415 416 debugf0("MC: %s()\n", __func__); 417 418 if (pci_enable_device(pdev) < 0) 419 return -EIO; 420 421 rc = x38_probe1(pdev, ent->driver_data); 422 if (!mci_pdev) 423 mci_pdev = pci_dev_get(pdev); 424 425 return rc; 426 } 427 428 static void __devexit x38_remove_one(struct pci_dev *pdev) 429 { 430 struct mem_ctl_info *mci; 431 432 debugf0("%s()\n", __func__); 433 434 mci = edac_mc_del_mc(&pdev->dev); 435 if (!mci) 436 return; 437 438 iounmap(mci->pvt_info); 439 440 edac_mc_free(mci); 441 } 442 443 static DEFINE_PCI_DEVICE_TABLE(x38_pci_tbl) = { 444 { 445 PCI_VEND_DEV(INTEL, X38_HB), PCI_ANY_ID, PCI_ANY_ID, 0, 0, 446 X38}, 447 { 448 0, 449 } /* 0 terminated list. */ 450 }; 451 452 MODULE_DEVICE_TABLE(pci, x38_pci_tbl); 453 454 static struct pci_driver x38_driver = { 455 .name = EDAC_MOD_STR, 456 .probe = x38_init_one, 457 .remove = __devexit_p(x38_remove_one), 458 .id_table = x38_pci_tbl, 459 }; 460 461 static int __init x38_init(void) 462 { 463 int pci_rc; 464 465 debugf3("MC: %s()\n", __func__); 466 467 /* Ensure that the OPSTATE is set correctly for POLL or NMI */ 468 opstate_init(); 469 470 pci_rc = pci_register_driver(&x38_driver); 471 if (pci_rc < 0) 472 goto fail0; 473 474 if (!mci_pdev) { 475 x38_registered = 0; 476 mci_pdev = pci_get_device(PCI_VENDOR_ID_INTEL, 477 PCI_DEVICE_ID_INTEL_X38_HB, NULL); 478 if (!mci_pdev) { 479 debugf0("x38 pci_get_device fail\n"); 480 pci_rc = -ENODEV; 481 goto fail1; 482 } 483 484 pci_rc = x38_init_one(mci_pdev, x38_pci_tbl); 485 if (pci_rc < 0) { 486 debugf0("x38 init fail\n"); 487 pci_rc = -ENODEV; 488 goto fail1; 489 } 490 } 491 492 return 0; 493 494 fail1: 495 pci_unregister_driver(&x38_driver); 496 497 fail0: 498 if (mci_pdev) 499 pci_dev_put(mci_pdev); 500 501 return pci_rc; 502 } 503 504 static void __exit x38_exit(void) 505 { 506 debugf3("MC: %s()\n", __func__); 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"); 524