drivers/watchdog/hpwdt.c

   1 /*
   2  *      HP WatchDog Driver
   3  *      based on
   4  *
   5  *      SoftDog 0.05:   A Software Watchdog Device
   6  *
   7  *      (c) Copyright 2007 Hewlett-Packard Development Company, L.P.
   8  *      Thomas Mingarelli <thomas.mingarelli@hp.com>
   9  *
  10  *      This program is free software; you can redistribute it and/or
  11  *      modify it under the terms of the GNU General Public License
  12  *      version 2 as published by the Free Software Foundation
  13  *
  14  */
  15
  16 #include <linux/device.h>
  17 #include <linux/fs.h>
  18 #include <linux/init.h>
  19 #include <linux/interrupt.h>
  20 #include <linux/io.h>
  21 #include <linux/irq.h>
  22 #include <linux/nmi.h>
  23 #include <linux/kernel.h>
  24 #include <linux/miscdevice.h>
  25 #include <linux/mm.h>
  26 #include <linux/module.h>
  27 #include <linux/kdebug.h>
  28 #include <linux/moduleparam.h>
  29 #include <linux/notifier.h>
  30 #include <linux/pci.h>
  31 #include <linux/pci_ids.h>
  32 #include <linux/reboot.h>
  33 #include <linux/sched.h>
  34 #include <linux/timer.h>
  35 #include <linux/types.h>
  36 #include <linux/uaccess.h>
  37 #include <linux/watchdog.h>
  38 #include <linux/dmi.h>
  39 #include <linux/efi.h>
  40 #include <linux/string.h>
  41 #include <linux/bootmem.h>
  42 #include <linux/slab.h>
  43 #include <asm/desc.h>
  44 #include <asm/cacheflush.h>
  45
  46 #define PCI_BIOS32_SD_VALUE             0x5F32335F      /* "_32_" */
  47 #define CRU_BIOS_SIGNATURE_VALUE        0x55524324
  48 #define PCI_BIOS32_PARAGRAPH_LEN        16
  49 #define PCI_ROM_BASE1                   0x000F0000
  50 #define ROM_SIZE                        0x10000
  51 #define HPWDT_VERSION                   "1.1.1"
  52
  53 struct bios32_service_dir {
  54         u32 signature;
  55         u32 entry_point;
  56         u8 revision;
  57         u8 length;
  58         u8 checksum;
  59         u8 reserved[5];
  60 };
  61
  62 /* type 212 */
  63 struct smbios_cru64_info {
  64         u8 type;
  65         u8 byte_length;
  66         u16 handle;
  67         u32 signature;
  68         u64 physical_address;
  69         u32 double_length;
  70         u32 double_offset;
  71 };
  72 #define SMBIOS_CRU64_INFORMATION        212
  73
  74 struct cmn_registers {
  75         union {
  76                 struct {
  77                         u8 ral;
  78                         u8 rah;
  79                         u16 rea2;
  80                 };
  81                 u32 reax;
  82         } u1;
  83         union {
  84                 struct {
  85                         u8 rbl;
  86                         u8 rbh;
  87                         u8 reb2l;
  88                         u8 reb2h;
  89                 };
  90                 u32 rebx;
  91         } u2;
  92         union {
  93                 struct {
  94                         u8 rcl;
  95                         u8 rch;
  96                         u16 rec2;
  97                 };
  98                 u32 recx;
  99         } u3;
 100         union {
 101                 struct {
 102                         u8 rdl;
 103                         u8 rdh;
 104                         u16 red2;
 105                 };
 106                 u32 redx;
 107         } u4;
 108
 109         u32 resi;
 110         u32 redi;
 111         u16 rds;
 112         u16 res;
 113         u32 reflags;
 114 }  __attribute__((packed));
 115
 116 #define DEFAULT_MARGIN  30
 117 static unsigned int soft_margin = DEFAULT_MARGIN;       /* in seconds */
 118 static unsigned int reload;                     /* the computed soft_margin */
 119 static int nowayout = WATCHDOG_NOWAYOUT;
 120 static char expect_release;
 121 static unsigned long hpwdt_is_open;
 122 static unsigned int allow_kdump;
 123 static unsigned int hpwdt_nmi_sourcing;
 124 static unsigned int priority;           /* hpwdt at end of die_notify list */
 125
 126 static void __iomem *pci_mem_addr;              /* the PCI-memory address */
 127 static unsigned long __iomem *hpwdt_timer_reg;
 128 static unsigned long __iomem *hpwdt_timer_con;
 129
 130 static DEFINE_SPINLOCK(rom_lock);
 131
 132 static void *cru_rom_addr;
 133
 134 static struct cmn_registers cmn_regs;
 135
 136 static struct pci_device_id hpwdt_devices[] = {
 137         { PCI_DEVICE(PCI_VENDOR_ID_COMPAQ, 0xB203) },
 138         { PCI_DEVICE(PCI_VENDOR_ID_HP, 0x3306) },
 139         {0},                    /* terminate list */
 140 };
 141 MODULE_DEVICE_TABLE(pci, hpwdt_devices);
 142
 143 extern asmlinkage void asminline_call(struct cmn_registers *pi86Regs,
 144                                                 unsigned long *pRomEntry);
 145
 146 #ifndef CONFIG_X86_64
 147 /* --32 Bit Bios------------------------------------------------------------ */
 148
 149 #define HPWDT_ARCH      32
 150
 151 asm(".text                          \n\t"
 152     ".align 4                       \n"
 153     "asminline_call:                \n\t"
 154     "pushl       %ebp               \n\t"
 155     "movl        %esp, %ebp         \n\t"
 156     "pusha                          \n\t"
 157     "pushf                          \n\t"
 158     "push        %es                \n\t"
 159     "push        %ds                \n\t"
 160     "pop         %es                \n\t"
 161     "movl        8(%ebp),%eax       \n\t"
 162     "movl        4(%eax),%ebx       \n\t"
 163     "movl        8(%eax),%ecx       \n\t"
 164     "movl        12(%eax),%edx      \n\t"
 165     "movl        16(%eax),%esi      \n\t"
 166     "movl        20(%eax),%edi      \n\t"
 167     "movl        (%eax),%eax        \n\t"
 168     "push        %cs                \n\t"
 169     "call        *12(%ebp)          \n\t"
 170     "pushf                          \n\t"
 171     "pushl       %eax               \n\t"
 172     "movl        8(%ebp),%eax       \n\t"
 173     "movl        %ebx,4(%eax)       \n\t"
 174     "movl        %ecx,8(%eax)       \n\t"
 175     "movl        %edx,12(%eax)      \n\t"
 176     "movl        %esi,16(%eax)      \n\t"
 177     "movl        %edi,20(%eax)      \n\t"
 178     "movw        %ds,24(%eax)       \n\t"
 179     "movw        %es,26(%eax)       \n\t"
 180     "popl        %ebx               \n\t"
 181     "movl        %ebx,(%eax)        \n\t"
 182     "popl        %ebx               \n\t"
 183     "movl        %ebx,28(%eax)      \n\t"
 184     "pop         %es                \n\t"
 185     "popf                           \n\t"
 186     "popa                           \n\t"
 187     "leave                          \n\t"
 188     "ret                            \n\t"
 189     ".previous");
 190
 191
 192 /*
 193  *      cru_detect
 194  *
 195  *      Routine Description:
 196  *      This function uses the 32-bit BIOS Service Directory record to
 197  *      search for a $CRU record.
 198  *
 199  *      Return Value:
 200  *      0        :  SUCCESS
 201  *      <0       :  FAILURE
 202  */
 203 static int __devinit cru_detect(unsigned long map_entry,
 204         unsigned long map_offset)
 205 {
 206         void *bios32_map;
 207         unsigned long *bios32_entrypoint;
 208         unsigned long cru_physical_address;
 209         unsigned long cru_length;
 210         unsigned long physical_bios_base = 0;
 211         unsigned long physical_bios_offset = 0;
 212         int retval = -ENODEV;
 213
 214         bios32_map = ioremap(map_entry, (2 * PAGE_SIZE));
 215
 216         if (bios32_map == NULL)
 217                 return -ENODEV;
 218
 219         bios32_entrypoint = bios32_map + map_offset;
 220
 221         cmn_regs.u1.reax = CRU_BIOS_SIGNATURE_VALUE;
 222
 223         set_memory_x((unsigned long)bios32_entrypoint, (2 * PAGE_SIZE));
 224         asminline_call(&cmn_regs, bios32_entrypoint);
 225
 226         if (cmn_regs.u1.ral != 0) {
 227                 printk(KERN_WARNING
 228                         "hpwdt: Call succeeded but with an error: 0x%x\n",
 229                         cmn_regs.u1.ral);
 230         } else {
 231                 physical_bios_base = cmn_regs.u2.rebx;
 232                 physical_bios_offset = cmn_regs.u4.redx;
 233                 cru_length = cmn_regs.u3.recx;
 234                 cru_physical_address =
 235                         physical_bios_base + physical_bios_offset;
 236
 237                 /* If the values look OK, then map it in. */
 238                 if ((physical_bios_base + physical_bios_offset)) {
 239                         cru_rom_addr =
 240                                 ioremap(cru_physical_address, cru_length);
 241                         if (cru_rom_addr) {
 242                                 set_memory_x((unsigned long)cru_rom_addr, cru_length);
 243                                 retval = 0;
 244                         }
 245                 }
 246
 247                 printk(KERN_DEBUG "hpwdt: CRU Base Address:   0x%lx\n",
 248                         physical_bios_base);
 249                 printk(KERN_DEBUG "hpwdt: CRU Offset Address: 0x%lx\n",
 250                         physical_bios_offset);
 251                 printk(KERN_DEBUG "hpwdt: CRU Length:         0x%lx\n",
 252                         cru_length);
 253                 printk(KERN_DEBUG "hpwdt: CRU Mapped Address: 0x%x\n",
 254                         (unsigned int)&cru_rom_addr);
 255         }
 256         iounmap(bios32_map);
 257         return retval;
 258 }
 259
 260 /*
 261  *      bios_checksum
 262  */
 263 static int __devinit bios_checksum(const char __iomem *ptr, int len)
 264 {
 265         char sum = 0;
 266         int i;
 267
 268         /*
 269          * calculate checksum of size bytes. This should add up
 270          * to zero if we have a valid header.
 271          */
 272         for (i = 0; i < len; i++)
 273                 sum += ptr[i];
 274
 275         return ((sum == 0) && (len > 0));
 276 }
 277
 278 /*
 279  *      bios32_present
 280  *
 281  *      Routine Description:
 282  *      This function finds the 32-bit BIOS Service Directory
 283  *
 284  *      Return Value:
 285  *      0        :  SUCCESS
 286  *      <0       :  FAILURE
 287  */
 288 static int __devinit bios32_present(const char __iomem *p)
 289 {
 290         struct bios32_service_dir *bios_32_ptr;
 291         int length;
 292         unsigned long map_entry, map_offset;
 293
 294         bios_32_ptr = (struct bios32_service_dir *) p;
 295
 296         /*
 297          * Search for signature by checking equal to the swizzled value
 298          * instead of calling another routine to perform a strcmp.
 299          */
 300         if (bios_32_ptr->signature == PCI_BIOS32_SD_VALUE) {
 301                 length = bios_32_ptr->length * PCI_BIOS32_PARAGRAPH_LEN;
 302                 if (bios_checksum(p, length)) {
 303                         /*
 304                          * According to the spec, we're looking for the
 305                          * first 4KB-aligned address below the entrypoint
 306                          * listed in the header. The Service Directory code
 307                          * is guaranteed to occupy no more than 2 4KB pages.
 308                          */
 309                         map_entry = bios_32_ptr->entry_point & ~(PAGE_SIZE - 1);
 310                         map_offset = bios_32_ptr->entry_point - map_entry;
 311
 312                         return cru_detect(map_entry, map_offset);
 313                 }
 314         }
 315         return -ENODEV;
 316 }
 317
 318 static int __devinit detect_cru_service(void)
 319 {
 320         char __iomem *p, *q;
 321         int rc = -1;
 322
 323         /*
 324          * Search from 0x0f0000 through 0x0fffff, inclusive.
 325          */
 326         p = ioremap(PCI_ROM_BASE1, ROM_SIZE);
 327         if (p == NULL)
 328                 return -ENOMEM;
 329
 330         for (q = p; q < p + ROM_SIZE; q += 16) {
 331                 rc = bios32_present(q);
 332                 if (!rc)
 333                         break;
 334         }
 335         iounmap(p);
 336         return rc;
 337 }
 338
 339 #else
 340 /* --64 Bit Bios------------------------------------------------------------ */
 341
 342 #define HPWDT_ARCH      64
 343
 344 asm(".text                      \n\t"
 345     ".align 4                   \n"
 346     "asminline_call:            \n\t"
 347     "pushq      %rbp            \n\t"
 348     "movq       %rsp, %rbp      \n\t"
 349     "pushq      %rax            \n\t"
 350     "pushq      %rbx            \n\t"
 351     "pushq      %rdx            \n\t"
 352     "pushq      %r12            \n\t"
 353     "pushq      %r9             \n\t"
 354     "movq       %rsi, %r12      \n\t"
 355     "movq       %rdi, %r9       \n\t"
 356     "movl       4(%r9),%ebx     \n\t"
 357     "movl       8(%r9),%ecx     \n\t"
 358     "movl       12(%r9),%edx    \n\t"
 359     "movl       16(%r9),%esi    \n\t"
 360     "movl       20(%r9),%edi    \n\t"
 361     "movl       (%r9),%eax      \n\t"
 362     "call       *%r12           \n\t"
 363     "pushfq                     \n\t"
 364     "popq        %r12           \n\t"
 365     "movl       %eax, (%r9)     \n\t"
 366     "movl       %ebx, 4(%r9)    \n\t"
 367     "movl       %ecx, 8(%r9)    \n\t"
 368     "movl       %edx, 12(%r9)   \n\t"
 369     "movl       %esi, 16(%r9)   \n\t"
 370     "movl       %edi, 20(%r9)   \n\t"
 371     "movq       %r12, %rax      \n\t"
 372     "movl       %eax, 28(%r9)   \n\t"
 373     "popq       %r9             \n\t"
 374     "popq       %r12            \n\t"
 375     "popq       %rdx            \n\t"
 376     "popq       %rbx            \n\t"
 377     "popq       %rax            \n\t"
 378     "leave                      \n\t"
 379     "ret                        \n\t"
 380     ".previous");
 381
 382 /*
 383  *      dmi_find_cru
 384  *
 385  *      Routine Description:
 386  *      This function checks whether or not a SMBIOS/DMI record is
 387  *      the 64bit CRU info or not
 388  */
 389 static void __devinit dmi_find_cru(const struct dmi_header *dm, void *dummy)
 390 {
 391         struct smbios_cru64_info *smbios_cru64_ptr;
 392         unsigned long cru_physical_address;
 393
 394         if (dm->type == SMBIOS_CRU64_INFORMATION) {
 395                 smbios_cru64_ptr = (struct smbios_cru64_info *) dm;
 396                 if (smbios_cru64_ptr->signature == CRU_BIOS_SIGNATURE_VALUE) {
 397                         cru_physical_address =
 398                                 smbios_cru64_ptr->physical_address +
 399                                 smbios_cru64_ptr->double_offset;
 400                         cru_rom_addr = ioremap(cru_physical_address,
 401                                 smbios_cru64_ptr->double_length);
 402                         set_memory_x((unsigned long)cru_rom_addr & PAGE_MASK,
 403                                 smbios_cru64_ptr->double_length >> PAGE_SHIFT);
 404                 }
 405         }
 406 }
 407
 408 static int __devinit detect_cru_service(void)
 409 {
 410         cru_rom_addr = NULL;
 411
 412         dmi_walk(dmi_find_cru, NULL);
 413
 414         /* if cru_rom_addr has been set then we found a CRU service */
 415         return ((cru_rom_addr != NULL) ? 0 : -ENODEV);
 416 }
 417
 418 /* ------------------------------------------------------------------------- */
 419
 420 #endif
 421
 422 /*
 423  *      Watchdog operations
 424  */
 425 static void hpwdt_start(void)
 426 {
 427         reload = (soft_margin * 1000) / 128;
 428         iowrite16(reload, hpwdt_timer_reg);
 429         iowrite16(0x85, hpwdt_timer_con);
 430 }
 431
 432 static void hpwdt_stop(void)
 433 {
 434         unsigned long data;
 435
 436         data = ioread16(hpwdt_timer_con);
 437         data &= 0xFE;
 438         iowrite16(data, hpwdt_timer_con);
 439 }
 440
 441 static void hpwdt_ping(void)
 442 {
 443         iowrite16(reload, hpwdt_timer_reg);
 444 }
 445
 446 static int hpwdt_change_timer(int new_margin)
 447 {
 448         /* Arbitrary, can't find the card's limits */
 449         if (new_margin < 5 || new_margin > 600) {
 450                 printk(KERN_WARNING
 451                         "hpwdt: New value passed in is invalid: %d seconds.\n",
 452                         new_margin);
 453                 return -EINVAL;
 454         }
 455
 456         soft_margin = new_margin;
 457         printk(KERN_DEBUG
 458                 "hpwdt: New timer passed in is %d seconds.\n",
 459                 new_margin);
 460         reload = (soft_margin * 1000) / 128;
 461
 462         return 0;
 463 }
 464
 465 /*
 466  *      NMI Handler
 467  */
 468 static int hpwdt_pretimeout(struct notifier_block *nb, unsigned long ulReason,
 469                                 void *data)
 470 {
 471         unsigned long rom_pl;
 472         static int die_nmi_called;
 473
 474         if (ulReason != DIE_NMI && ulReason != DIE_NMI_IPI)
 475                 return NOTIFY_OK;
 476
 477         if (hpwdt_nmi_sourcing) {
 478                 spin_lock_irqsave(&rom_lock, rom_pl);
 479                 if (!die_nmi_called)
 480                         asminline_call(&cmn_regs, cru_rom_addr);
 481                 die_nmi_called = 1;
 482                 spin_unlock_irqrestore(&rom_lock, rom_pl);
 483                 if (cmn_regs.u1.ral == 0) {
 484                         printk(KERN_WARNING "hpwdt: An NMI occurred, "
 485                                 "but unable to determine source.\n");
 486                 } else {
 487                         if (allow_kdump)
 488                                 hpwdt_stop();
 489                         panic("An NMI occurred, please see the Integrated "
 490                                 "Management Log for details.\n");
 491                 }
 492         }
 493         return NOTIFY_OK;
 494 }
 495
 496 /*
 497  *      /dev/watchdog handling
 498  */
 499 static int hpwdt_open(struct inode *inode, struct file *file)
 500 {
 501         /* /dev/watchdog can only be opened once */
 502         if (test_and_set_bit(0, &hpwdt_is_open))
 503                 return -EBUSY;
 504
 505         /* Start the watchdog */
 506         hpwdt_start();
 507         hpwdt_ping();
 508
 509         return nonseekable_open(inode, file);
 510 }
 511
 512 static int hpwdt_release(struct inode *inode, struct file *file)
 513 {
 514         /* Stop the watchdog */
 515         if (expect_release == 42) {
 516                 hpwdt_stop();
 517         } else {
 518                 printk(KERN_CRIT
 519                         "hpwdt: Unexpected close, not stopping watchdog!\n");
 520                 hpwdt_ping();
 521         }
 522
 523         expect_release = 0;
 524
 525         /* /dev/watchdog is being closed, make sure it can be re-opened */
 526         clear_bit(0, &hpwdt_is_open);
 527
 528         return 0;
 529 }
 530
 531 static ssize_t hpwdt_write(struct file *file, const char __user *data,
 532         size_t len, loff_t *ppos)
 533 {
 534         /* See if we got the magic character 'V' and reload the timer */
 535         if (len) {
 536                 if (!nowayout) {
 537                         size_t i;
 538
 539                         /* note: just in case someone wrote the magic character
 540                          * five months ago... */
 541                         expect_release = 0;
 542
 543                         /* scan to see whether or not we got the magic char. */
 544                         for (i = 0; i != len; i++) {
 545                                 char c;
 546                                 if (get_user(c, data + i))
 547                                         return -EFAULT;
 548                                 if (c == 'V')
 549                                         expect_release = 42;
 550                         }
 551                 }
 552
 553                 /* someone wrote to us, we should reload the timer */
 554                 hpwdt_ping();
 555         }
 556
 557         return len;
 558 }
 559
 560 static struct watchdog_info ident = {
 561         .options = WDIOF_SETTIMEOUT |
 562                    WDIOF_KEEPALIVEPING |
 563                    WDIOF_MAGICCLOSE,
 564         .identity = "HP iLO2 HW Watchdog Timer",
 565 };
 566
 567 static long hpwdt_ioctl(struct file *file, unsigned int cmd,
 568         unsigned long arg)
 569 {
 570         void __user *argp = (void __user *)arg;
 571         int __user *p = argp;
 572         int new_margin;
 573         int ret = -ENOTTY;
 574
 575         switch (cmd) {
 576         case WDIOC_GETSUPPORT:
 577                 ret = 0;
 578                 if (copy_to_user(argp, &ident, sizeof(ident)))
 579                         ret = -EFAULT;
 580                 break;
 581
 582         case WDIOC_GETSTATUS:
 583         case WDIOC_GETBOOTSTATUS:
 584                 ret = put_user(0, p);
 585                 break;
 586
 587         case WDIOC_KEEPALIVE:
 588                 hpwdt_ping();
 589                 ret = 0;
 590                 break;
 591
 592         case WDIOC_SETTIMEOUT:
 593                 ret = get_user(new_margin, p);
 594                 if (ret)
 595                         break;
 596
 597                 ret = hpwdt_change_timer(new_margin);
 598                 if (ret)
 599                         break;
 600
 601                 hpwdt_ping();
 602                 /* Fall */
 603         case WDIOC_GETTIMEOUT:
 604                 ret = put_user(soft_margin, p);
 605                 break;
 606         }
 607         return ret;
 608 }
 609
 610 /*
 611  *      Kernel interfaces
 612  */
 613 static const struct file_operations hpwdt_fops = {
 614         .owner = THIS_MODULE,
 615         .llseek = no_llseek,
 616         .write = hpwdt_write,
 617         .unlocked_ioctl = hpwdt_ioctl,
 618         .open = hpwdt_open,
 619         .release = hpwdt_release,
 620 };
 621
 622 static struct miscdevice hpwdt_miscdev = {
 623         .minor = WATCHDOG_MINOR,
 624         .name = "watchdog",
 625         .fops = &hpwdt_fops,
 626 };
 627
 628 static struct notifier_block die_notifier = {
 629         .notifier_call = hpwdt_pretimeout,
 630         .priority = 0,
 631 };
 632
 633 /*
 634  *      Init & Exit
 635  */
 636
 637 #ifdef ARCH_HAS_NMI_WATCHDOG
 638 static void __devinit hpwdt_check_nmi_sourcing(struct pci_dev *dev)
 639 {
 640         /*
 641          * If nmi_watchdog is turned off then we can turn on
 642          * our nmi sourcing capability.
 643          */
 644         if (!nmi_watchdog_active())
 645                 hpwdt_nmi_sourcing = 1;
 646         else
 647                 dev_warn(&dev->dev, "NMI sourcing is disabled. To enable this "
 648                         "functionality you must reboot with nmi_watchdog=0 "
 649                         "and load the hpwdt driver with priority=1.\n");
 650 }
 651 #else
 652 static void __devinit hpwdt_check_nmi_sourcing(struct pci_dev *dev)
 653 {
 654         dev_warn(&dev->dev, "NMI sourcing is disabled. "
 655                 "Your kernel does not support a NMI Watchdog.\n");
 656 }
 657 #endif
 658
 659 static int __devinit hpwdt_init_one(struct pci_dev *dev,
 660                                         const struct pci_device_id *ent)
 661 {
 662         int retval;
 663
 664         /*
 665          * Check if we can do NMI sourcing or not
 666          */
 667         hpwdt_check_nmi_sourcing(dev);
 668
 669         /*
 670          * First let's find out if we are on an iLO2 server. We will
 671          * not run on a legacy ASM box.
 672          * So we only support the G5 ProLiant servers and higher.
 673          */
 674         if (dev->subsystem_vendor != PCI_VENDOR_ID_HP) {
 675                 dev_warn(&dev->dev,
 676                         "This server does not have an iLO2 ASIC.\n");
 677                 return -ENODEV;
 678         }
 679
 680         if (pci_enable_device(dev)) {
 681                 dev_warn(&dev->dev,
 682                         "Not possible to enable PCI Device: 0x%x:0x%x.\n",
 683                         ent->vendor, ent->device);
 684                 return -ENODEV;
 685         }
 686
 687         pci_mem_addr = pci_iomap(dev, 1, 0x80);
 688         if (!pci_mem_addr) {
 689                 dev_warn(&dev->dev,
 690                         "Unable to detect the iLO2 server memory.\n");
 691                 retval = -ENOMEM;
 692                 goto error_pci_iomap;
 693         }
 694         hpwdt_timer_reg = pci_mem_addr + 0x70;
 695         hpwdt_timer_con = pci_mem_addr + 0x72;
 696
 697         /* Make sure that we have a valid soft_margin */
 698         if (hpwdt_change_timer(soft_margin))
 699                 hpwdt_change_timer(DEFAULT_MARGIN);
 700
 701         /*
 702          * We need to map the ROM to get the CRU service.
 703          * For 32 bit Operating Systems we need to go through the 32 Bit
 704          * BIOS Service Directory
 705          * For 64 bit Operating Systems we get that service through SMBIOS.
 706          */
 707         retval = detect_cru_service();
 708         if (retval < 0) {
 709                 dev_warn(&dev->dev,
 710                         "Unable to detect the %d Bit CRU Service.\n",
 711                         HPWDT_ARCH);
 712                 goto error_get_cru;
 713         }
 714
 715         /*
 716          * We know this is the only CRU call we need to make so lets keep as
 717          * few instructions as possible once the NMI comes in.
 718          */
 719         cmn_regs.u1.rah = 0x0D;
 720         cmn_regs.u1.ral = 0x02;
 721
 722         /*
 723          * If the priority is set to 1, then we will be put first on the
 724          * die notify list to handle a critical NMI. The default is to
 725          * be last so other users of the NMI signal can function.
 726          */
 727         if (priority)
 728                 die_notifier.priority = 0x7FFFFFFF;
 729
 730         retval = register_die_notifier(&die_notifier);
 731         if (retval != 0) {
 732                 dev_warn(&dev->dev,
 733                         "Unable to register a die notifier (err=%d).\n",
 734                         retval);
 735                 goto error_die_notifier;
 736         }
 737
 738         retval = misc_register(&hpwdt_miscdev);
 739         if (retval < 0) {
 740                 dev_warn(&dev->dev,
 741                         "Unable to register miscdev on minor=%d (err=%d).\n",
 742                         WATCHDOG_MINOR, retval);
 743                 goto error_misc_register;
 744         }
 745
 746         printk(KERN_INFO
 747                 "hp Watchdog Timer Driver: %s"
 748                 ", timer margin: %d seconds (nowayout=%d)"
 749                 ", allow kernel dump: %s (default = 0/OFF)"
 750                 ", priority: %s (default = 0/LAST).\n",
 751                 HPWDT_VERSION, soft_margin, nowayout,
 752                 (allow_kdump == 0) ? "OFF" : "ON",
 753                 (priority == 0) ? "LAST" : "FIRST");
 754
 755         return 0;
 756
 757 error_misc_register:
 758         unregister_die_notifier(&die_notifier);
 759 error_die_notifier:
 760         if (cru_rom_addr)
 761                 iounmap(cru_rom_addr);
 762 error_get_cru:
 763         pci_iounmap(dev, pci_mem_addr);
 764 error_pci_iomap:
 765         pci_disable_device(dev);
 766         return retval;
 767 }
 768
 769 static void __devexit hpwdt_exit(struct pci_dev *dev)
 770 {
 771         if (!nowayout)
 772                 hpwdt_stop();
 773
 774         misc_deregister(&hpwdt_miscdev);
 775         unregister_die_notifier(&die_notifier);
 776
 777         if (cru_rom_addr)
 778                 iounmap(cru_rom_addr);
 779         pci_iounmap(dev, pci_mem_addr);
 780         pci_disable_device(dev);
 781 }
 782
 783 static struct pci_driver hpwdt_driver = {
 784         .name = "hpwdt",
 785         .id_table = hpwdt_devices,
 786         .probe = hpwdt_init_one,
 787         .remove = __devexit_p(hpwdt_exit),
 788 };
 789
 790 static void __exit hpwdt_cleanup(void)
 791 {
 792         pci_unregister_driver(&hpwdt_driver);
 793 }
 794
 795 static int __init hpwdt_init(void)
 796 {
 797         return pci_register_driver(&hpwdt_driver);
 798 }
 799
 800 MODULE_AUTHOR("Tom Mingarelli");
 801 MODULE_DESCRIPTION("hp watchdog driver");
 802 MODULE_LICENSE("GPL");
 803 MODULE_VERSION(HPWDT_VERSION);
 804 MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
 805
 806 module_param(soft_margin, int, 0);
 807 MODULE_PARM_DESC(soft_margin, "Watchdog timeout in seconds");
 808
 809 module_param(allow_kdump, int, 0);
 810 MODULE_PARM_DESC(allow_kdump, "Start a kernel dump after NMI occurs");
 811
 812 module_param(nowayout, int, 0);
 813 MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
 814                 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
 815
 816 module_param(priority, int, 0);
 817 MODULE_PARM_DESC(priority, "The hpwdt driver handles NMIs first or last"
 818                 " (default = 0/Last)\n");
 819
 820 module_init(hpwdt_init);
 821 module_exit(hpwdt_cleanup);