drivers/edac/r82600_edac.c

   1 /*
   2  * Radisys 82600 Embedded chipset Memory Controller kernel module
   3  * (C) 2005 EADS Astrium
   4  * This file may be distributed under the terms of the
   5  * GNU General Public License.
   6  *
   7  * Written by Tim Small <tim@buttersideup.com>, based on work by Thayne
   8  * Harbaugh, Dan Hollis <goemon at anime dot net> and others.
   9  *
  10  * $Id: edac_r82600.c,v 1.1.2.6 2005/10/05 00:43:44 dsp_llnl Exp $
  11  *
  12  * Written with reference to 82600 High Integration Dual PCI System
  13  * Controller Data Book:
  14  * http://www.radisys.com/files/support_downloads/007-01277-0002.82600DataBook.pdf
  15  * references to this document given in []
  16  */
  17
  18 #include <linux/module.h>
  19 #include <linux/init.h>
  20 #include <linux/pci.h>
  21 #include <linux/pci_ids.h>
  22 #include <linux/slab.h>
  23 #include "edac_mc.h"
  24
  25 #define R82600_REVISION " Ver: 2.0.1 " __DATE__
  26 #define EDAC_MOD_STR    "r82600_edac"
  27
  28 #define r82600_printk(level, fmt, arg...) \
  29         edac_printk(level, "r82600", fmt, ##arg)
  30
  31 #define r82600_mc_printk(mci, level, fmt, arg...) \
  32         edac_mc_chipset_printk(mci, level, "r82600", fmt, ##arg)
  33
  34 /* Radisys say "The 82600 integrates a main memory SDRAM controller that
  35  * supports up to four banks of memory. The four banks can support a mix of
  36  * sizes of 64 bit wide (72 bits with ECC) Synchronous DRAM (SDRAM) DIMMs,
  37  * each of which can be any size from 16MB to 512MB. Both registered (control
  38  * signals buffered) and unbuffered DIMM types are supported. Mixing of
  39  * registered and unbuffered DIMMs as well as mixing of ECC and non-ECC DIMMs
  40  * is not allowed. The 82600 SDRAM interface operates at the same frequency as
  41  * the CPU bus, 66MHz, 100MHz or 133MHz."
  42  */
  43
  44 #define R82600_NR_CSROWS 4
  45 #define R82600_NR_CHANS  1
  46 #define R82600_NR_DIMMS  4
  47
  48 #define R82600_BRIDGE_ID  0x8200
  49
  50 /* Radisys 82600 register addresses - device 0 function 0 - PCI bridge */
  51 #define R82600_DRAMC    0x57    /* Various SDRAM related control bits
  52                                  * all bits are R/W
  53                                  *
  54                                  * 7    SDRAM ISA Hole Enable
  55                                  * 6    Flash Page Mode Enable
  56                                  * 5    ECC Enable: 1=ECC 0=noECC
  57                                  * 4    DRAM DIMM Type: 1=
  58                                  * 3    BIOS Alias Disable
  59                                  * 2    SDRAM BIOS Flash Write Enable
  60                                  * 1:0  SDRAM Refresh Rate: 00=Disabled
  61                                  *          01=7.8usec (256Mbit SDRAMs)
  62                                  *          10=15.6us 11=125usec
  63                                  */
  64
  65 #define R82600_SDRAMC   0x76    /* "SDRAM Control Register"
  66                                  * More SDRAM related control bits
  67                                  * all bits are R/W
  68                                  *
  69                                  * 15:8 Reserved.
  70                                  *
  71                                  * 7:5  Special SDRAM Mode Select
  72                                  *
  73                                  * 4    Force ECC
  74                                  *
  75                                  *        1=Drive ECC bits to 0 during
  76                                  *          write cycles (i.e. ECC test mode)
  77                                  *
  78                                  *        0=Normal ECC functioning
  79                                  *
  80                                  * 3    Enhanced Paging Enable
  81                                  *
  82                                  * 2    CAS# Latency 0=3clks 1=2clks
  83                                  *
  84                                  * 1    RAS# to CAS# Delay 0=3 1=2
  85                                  *
  86                                  * 0    RAS# Precharge     0=3 1=2
  87                                  */
  88
  89 #define R82600_EAP      0x80    /* ECC Error Address Pointer Register
  90                                  *
  91                                  * 31    Disable Hardware Scrubbing (RW)
  92                                  *        0=Scrub on corrected read
  93                                  *        1=Don't scrub on corrected read
  94                                  *
  95                                  * 30:12 Error Address Pointer (RO)
  96                                  *        Upper 19 bits of error address
  97                                  *
  98                                  * 11:4  Syndrome Bits (RO)
  99                                  *
 100                                  * 3     BSERR# on multibit error (RW)
 101                                  *        1=enable 0=disable
 102                                  *
 103                                  * 2     NMI on Single Bit Eror (RW)
 104                                  *        1=NMI triggered by SBE n.b. other
 105                                  *          prerequeists
 106                                  *        0=NMI not triggered
 107                                  *
 108                                  * 1     MBE (R/WC)
 109                                  *        read 1=MBE at EAP (see above)
 110                                  *        read 0=no MBE, or SBE occurred first
 111                                  *        write 1=Clear MBE status (must also
 112                                  *          clear SBE)
 113                                  *        write 0=NOP
 114                                  *
 115                                  * 1     SBE (R/WC)
 116                                  *        read 1=SBE at EAP (see above)
 117                                  *        read 0=no SBE, or MBE occurred first
 118                                  *        write 1=Clear SBE status (must also
 119                                  *          clear MBE)
 120                                  *        write 0=NOP
 121                                  */
 122
 123 #define R82600_DRBA     0x60    /* + 0x60..0x63 SDRAM Row Boundry Address
 124                                  *  Registers
 125                                  *
 126                                  * 7:0  Address lines 30:24 - upper limit of
 127                                  * each row [p57]
 128                                  */
 129
 130 struct r82600_error_info {
 131         u32 eapr;
 132 };
 133
 134 static unsigned int disable_hardware_scrub = 0;
 135
 136 static void r82600_get_error_info (struct mem_ctl_info *mci,
 137                 struct r82600_error_info *info)
 138 {
 139         struct pci_dev *pdev;
 140
 141         pdev = to_pci_dev(mci->dev);
 142         pci_read_config_dword(pdev, R82600_EAP, &info->eapr);
 143
 144         if (info->eapr & BIT(0))
 145                 /* Clear error to allow next error to be reported [p.62] */
 146                 pci_write_bits32(pdev, R82600_EAP,
 147                                 ((u32) BIT(0) & (u32) BIT(1)),
 148                                 ((u32) BIT(0) & (u32) BIT(1)));
 149
 150         if (info->eapr & BIT(1))
 151                 /* Clear error to allow next error to be reported [p.62] */
 152                 pci_write_bits32(pdev, R82600_EAP,
 153                                 ((u32) BIT(0) & (u32) BIT(1)),
 154                                 ((u32) BIT(0) & (u32) BIT(1)));
 155 }
 156
 157 static int r82600_process_error_info (struct mem_ctl_info *mci,
 158                 struct r82600_error_info *info, int handle_errors)
 159 {
 160         int error_found;
 161         u32 eapaddr, page;
 162         u32 syndrome;
 163
 164         error_found = 0;
 165
 166         /* bits 30:12 store the upper 19 bits of the 32 bit error address */
 167         eapaddr = ((info->eapr >> 12) & 0x7FFF) << 13;
 168         /* Syndrome in bits 11:4 [p.62]       */
 169         syndrome = (info->eapr >> 4) & 0xFF;
 170
 171         /* the R82600 reports at less than page *
 172          * granularity (upper 19 bits only)     */
 173         page = eapaddr >> PAGE_SHIFT;
 174
 175         if (info->eapr & BIT(0)) {  /* CE? */
 176                 error_found = 1;
 177
 178                 if (handle_errors)
 179                         edac_mc_handle_ce(mci, page, 0,  /* not avail */
 180                                         syndrome,
 181                                         edac_mc_find_csrow_by_page(mci, page),
 182                                         0,  /* channel */
 183                                         mci->ctl_name);
 184         }
 185
 186         if (info->eapr & BIT(1)) {  /* UE? */
 187                 error_found = 1;
 188
 189                 if (handle_errors)
 190                         /* 82600 doesn't give enough info */
 191                         edac_mc_handle_ue(mci, page, 0,
 192                                 edac_mc_find_csrow_by_page(mci, page),
 193                                 mci->ctl_name);
 194         }
 195
 196         return error_found;
 197 }
 198
 199 static void r82600_check(struct mem_ctl_info *mci)
 200 {
 201         struct r82600_error_info info;
 202
 203         debugf1("MC%d: %s()\n", mci->mc_idx, __func__);
 204         r82600_get_error_info(mci, &info);
 205         r82600_process_error_info(mci, &info, 1);
 206 }
 207
 208 static inline int ecc_enabled(u8 dramcr)
 209 {
 210         return dramcr & BIT(5);
 211 }
 212
 213 static void r82600_init_csrows(struct mem_ctl_info *mci, struct pci_dev *pdev,
 214                 u8 dramcr)
 215 {
 216         struct csrow_info *csrow;
 217         int index;
 218         u8 drbar;  /* SDRAM Row Boundry Address Register */
 219         u32 row_high_limit, row_high_limit_last;
 220         u32 reg_sdram, ecc_on, row_base;
 221
 222         ecc_on = ecc_enabled(dramcr);
 223         reg_sdram = dramcr & BIT(4);
 224         row_high_limit_last = 0;
 225
 226         for (index = 0; index < mci->nr_csrows; index++) {
 227                 csrow = &mci->csrows[index];
 228
 229                 /* find the DRAM Chip Select Base address and mask */
 230                 pci_read_config_byte(pdev, R82600_DRBA + index, &drbar);
 231
 232                 debugf1("%s() Row=%d DRBA = %#0x\n", __func__, index, drbar);
 233
 234                 row_high_limit = ((u32) drbar << 24);
 235 /*              row_high_limit = ((u32)drbar << 24) | 0xffffffUL; */
 236
 237                 debugf1("%s() Row=%d, Boundry Address=%#0x, Last = %#0x\n",
 238                         __func__, index, row_high_limit, row_high_limit_last);
 239
 240                 /* Empty row [p.57] */
 241                 if (row_high_limit == row_high_limit_last)
 242                         continue;
 243
 244                 row_base = row_high_limit_last;
 245
 246                 csrow->first_page = row_base >> PAGE_SHIFT;
 247                 csrow->last_page = (row_high_limit >> PAGE_SHIFT) - 1;
 248                 csrow->nr_pages = csrow->last_page - csrow->first_page + 1;
 249                 /* Error address is top 19 bits - so granularity is      *
 250                  * 14 bits                                               */
 251                 csrow->grain = 1 << 14;
 252                 csrow->mtype = reg_sdram ? MEM_RDDR : MEM_DDR;
 253                 /* FIXME - check that this is unknowable with this chipset */
 254                 csrow->dtype = DEV_UNKNOWN;
 255
 256                 /* Mode is global on 82600 */
 257                 csrow->edac_mode = ecc_on ? EDAC_SECDED : EDAC_NONE;
 258                 row_high_limit_last = row_high_limit;
 259         }
 260 }
 261
 262 static int r82600_probe1(struct pci_dev *pdev, int dev_idx)
 263 {
 264         struct mem_ctl_info *mci;
 265         u8 dramcr;
 266         u32 eapr;
 267         u32 scrub_disabled;
 268         u32 sdram_refresh_rate;
 269         struct r82600_error_info discard;
 270
 271         debugf0("%s()\n", __func__);
 272         pci_read_config_byte(pdev, R82600_DRAMC, &dramcr);
 273         pci_read_config_dword(pdev, R82600_EAP, &eapr);
 274         scrub_disabled = eapr & BIT(31);
 275         sdram_refresh_rate = dramcr & (BIT(0) | BIT(1));
 276         debugf2("%s(): sdram refresh rate = %#0x\n", __func__,
 277                 sdram_refresh_rate);
 278         debugf2("%s(): DRAMC register = %#0x\n", __func__, dramcr);
 279         mci = edac_mc_alloc(0, R82600_NR_CSROWS, R82600_NR_CHANS);
 280
 281         if (mci == NULL)
 282                 return -ENOMEM;
 283
 284         debugf0("%s(): mci = %p\n", __func__, mci);
 285         mci->dev = &pdev->dev;
 286         mci->mtype_cap = MEM_FLAG_RDDR | MEM_FLAG_DDR;
 287         mci->edac_ctl_cap = EDAC_FLAG_NONE | EDAC_FLAG_EC | EDAC_FLAG_SECDED;
 288         /* FIXME try to work out if the chip leads have been used for COM2
 289          * instead on this board? [MA6?] MAYBE:
 290          */
 291
 292         /* On the R82600, the pins for memory bits 72:65 - i.e. the   *
 293          * EC bits are shared with the pins for COM2 (!), so if COM2  *
 294          * is enabled, we assume COM2 is wired up, and thus no EDAC   *
 295          * is possible.                                               */
 296         mci->edac_cap = EDAC_FLAG_NONE | EDAC_FLAG_EC | EDAC_FLAG_SECDED;
 297
 298         if (ecc_enabled(dramcr)) {
 299                 if (scrub_disabled)
 300                         debugf3("%s(): mci = %p - Scrubbing disabled! EAP: "
 301                                 "%#0x\n", __func__, mci, eapr);
 302         } else
 303                 mci->edac_cap = EDAC_FLAG_NONE;
 304
 305         mci->mod_name = EDAC_MOD_STR;
 306         mci->mod_ver = R82600_REVISION;
 307         mci->ctl_name = "R82600";
 308         mci->edac_check = r82600_check;
 309         mci->ctl_page_to_phys = NULL;
 310         r82600_init_csrows(mci, pdev, dramcr);
 311         r82600_get_error_info(mci, &discard);  /* clear counters */
 312
 313         /* Here we assume that we will never see multiple instances of this
 314          * type of memory controller.  The ID is therefore hardcoded to 0.
 315          */
 316         if (edac_mc_add_mc(mci,0)) {
 317                 debugf3("%s(): failed edac_mc_add_mc()\n", __func__);
 318                 goto fail;
 319         }
 320
 321         /* get this far and it's successful */
 322
 323         if (disable_hardware_scrub) {
 324                 debugf3("%s(): Disabling Hardware Scrub (scrub on error)\n",
 325                         __func__);
 326                 pci_write_bits32(pdev, R82600_EAP, BIT(31), BIT(31));
 327         }
 328
 329         debugf3("%s(): success\n", __func__);
 330         return 0;
 331
 332 fail:
 333         edac_mc_free(mci);
 334         return -ENODEV;
 335 }
 336
 337 /* returns count (>= 0), or negative on error */
 338 static int __devinit r82600_init_one(struct pci_dev *pdev,
 339                 const struct pci_device_id *ent)
 340 {
 341         debugf0("%s()\n", __func__);
 342
 343         /* don't need to call pci_device_enable() */
 344         return r82600_probe1(pdev, ent->driver_data);
 345 }
 346
 347 static void __devexit r82600_remove_one(struct pci_dev *pdev)
 348 {
 349         struct mem_ctl_info *mci;
 350
 351         debugf0("%s()\n", __func__);
 352
 353         if ((mci = edac_mc_del_mc(&pdev->dev)) == NULL)
 354                 return;
 355
 356         edac_mc_free(mci);
 357 }
 358
 359 static const struct pci_device_id r82600_pci_tbl[] __devinitdata = {
 360         {
 361                 PCI_DEVICE(PCI_VENDOR_ID_RADISYS, R82600_BRIDGE_ID)
 362         },
 363         {
 364                 0,
 365         }       /* 0 terminated list. */
 366 };
 367
 368 MODULE_DEVICE_TABLE(pci, r82600_pci_tbl);
 369
 370 static struct pci_driver r82600_driver = {
 371         .name = EDAC_MOD_STR,
 372         .probe = r82600_init_one,
 373         .remove = __devexit_p(r82600_remove_one),
 374         .id_table = r82600_pci_tbl,
 375 };
 376
 377 static int __init r82600_init(void)
 378 {
 379         return pci_register_driver(&r82600_driver);
 380 }
 381
 382 static void __exit r82600_exit(void)
 383 {
 384         pci_unregister_driver(&r82600_driver);
 385 }
 386
 387 module_init(r82600_init);
 388 module_exit(r82600_exit);
 389
 390 MODULE_LICENSE("GPL");
 391 MODULE_AUTHOR("Tim Small <tim@buttersideup.com> - WPAD Ltd. "
 392         "on behalf of EADS Astrium");
 393 MODULE_DESCRIPTION("MC support for Radisys 82600 memory controllers");
 394
 395 module_param(disable_hardware_scrub, bool, 0644);
 396 MODULE_PARM_DESC(disable_hardware_scrub,
 397                  "If set, disable the chipset's automatic scrub for CEs");