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/kernel.h>
  23 #include <linux/miscdevice.h>
  24 #include <linux/mm.h>
  25 #include <linux/module.h>
  26 #include <linux/kdebug.h>
  27 #include <linux/moduleparam.h>
  28 #include <linux/notifier.h>
  29 #include <linux/pci.h>
  30 #include <linux/pci_ids.h>
  31 #include <linux/reboot.h>
  32 #include <linux/sched.h>
  33 #include <linux/timer.h>
  34 #include <linux/types.h>
  35 #include <linux/uaccess.h>
  36 #include <linux/watchdog.h>
  37 #include <linux/dmi.h>
  38 #include <linux/efi.h>
  39 #include <linux/string.h>
  40 #include <linux/bootmem.h>
  41 #include <linux/slab.h>
  42 #include <asm/desc.h>
  43
  44 #define PCI_BIOS32_SD_VALUE             0x5F32335F      /* "_32_" */
  45 #define CRU_BIOS_SIGNATURE_VALUE        0x55524324
  46 #define PCI_BIOS32_PARAGRAPH_LEN        16
  47 #define PCI_ROM_BASE1                   0x000F0000
  48 #define ROM_SIZE                        0x10000
  49
  50 struct bios32_service_dir {
  51         u32 signature;
  52         u32 entry_point;
  53         u8 revision;
  54         u8 length;
  55         u8 checksum;
  56         u8 reserved[5];
  57 };
  58
  59 /* type 212 */
  60 struct smbios_cru64_info {
  61         u8 type;
  62         u8 byte_length;
  63         u16 handle;
  64         u32 signature;
  65         u64 physical_address;
  66         u32 double_length;
  67         u32 double_offset;
  68 };
  69 #define SMBIOS_CRU64_INFORMATION        212
  70
  71 struct cmn_registers {
  72         union {
  73                 struct {
  74                         u8 ral;
  75                         u8 rah;
  76                         u16 rea2;
  77                 };
  78                 u32 reax;
  79         } u1;
  80         union {
  81                 struct {
  82                         u8 rbl;
  83                         u8 rbh;
  84                         u8 reb2l;
  85                         u8 reb2h;
  86                 };
  87                 u32 rebx;
  88         } u2;
  89         union {
  90                 struct {
  91                         u8 rcl;
  92                         u8 rch;
  93                         u16 rec2;
  94                 };
  95                 u32 recx;
  96         } u3;
  97         union {
  98                 struct {
  99                         u8 rdl;
 100                         u8 rdh;
 101                         u16 red2;
 102                 };
 103                 u32 redx;
 104         } u4;
 105
 106         u32 resi;
 107         u32 redi;
 108         u16 rds;
 109         u16 res;
 110         u32 reflags;
 111 }  __attribute__((packed));
 112
 113 #define DEFAULT_MARGIN  30
 114 static unsigned int soft_margin = DEFAULT_MARGIN;       /* in seconds */
 115 static unsigned int reload;                     /* the computed soft_margin */
 116 static int nowayout = WATCHDOG_NOWAYOUT;
 117 static char expect_release;
 118 static unsigned long hpwdt_is_open;
 119 static unsigned int allow_kdump;
 120
 121 static void __iomem *pci_mem_addr;              /* the PCI-memory address */
 122 static unsigned long __iomem *hpwdt_timer_reg;
 123 static unsigned long __iomem *hpwdt_timer_con;
 124
 125 static DEFINE_SPINLOCK(rom_lock);
 126
 127 static void *cru_rom_addr;
 128
 129 static struct cmn_registers cmn_regs;
 130
 131 static struct pci_device_id hpwdt_devices[] = {
 132         {
 133          .vendor = PCI_VENDOR_ID_COMPAQ,
 134          .device = 0xB203,
 135          .subvendor = PCI_ANY_ID,
 136          .subdevice = PCI_ANY_ID,
 137         },
 138         {0},                    /* terminate list */
 139 };
 140 MODULE_DEVICE_TABLE(pci, hpwdt_devices);
 141
 142 extern asmlinkage void asminline_call(struct cmn_registers *pi86Regs, unsigned long *pRomEntry);
 143
 144 #ifndef CONFIG_X86_64
 145 /* --32 Bit Bios------------------------------------------------------------ */
 146
 147 #define HPWDT_ARCH      32
 148
 149 asm(".text                          \n\t"
 150     ".align 4                       \n"
 151     "asminline_call:                \n\t"
 152     "pushl       %ebp               \n\t"
 153     "movl        %esp, %ebp         \n\t"
 154     "pusha                          \n\t"
 155     "pushf                          \n\t"
 156     "push        %es                \n\t"
 157     "push        %ds                \n\t"
 158     "pop         %es                \n\t"
 159     "movl        8(%ebp),%eax       \n\t"
 160     "movl        4(%eax),%ebx       \n\t"
 161     "movl        8(%eax),%ecx       \n\t"
 162     "movl        12(%eax),%edx      \n\t"
 163     "movl        16(%eax),%esi      \n\t"
 164     "movl        20(%eax),%edi      \n\t"
 165     "movl        (%eax),%eax        \n\t"
 166     "push        %cs                \n\t"
 167     "call        *12(%ebp)          \n\t"
 168     "pushf                          \n\t"
 169     "pushl       %eax               \n\t"
 170     "movl        8(%ebp),%eax       \n\t"
 171     "movl        %ebx,4(%eax)       \n\t"
 172     "movl        %ecx,8(%eax)       \n\t"
 173     "movl        %edx,12(%eax)      \n\t"
 174     "movl        %esi,16(%eax)      \n\t"
 175     "movl        %edi,20(%eax)      \n\t"
 176     "movw        %ds,24(%eax)       \n\t"
 177     "movw        %es,26(%eax)       \n\t"
 178     "popl        %ebx               \n\t"
 179     "movl        %ebx,(%eax)        \n\t"
 180     "popl        %ebx               \n\t"
 181     "movl        %ebx,28(%eax)      \n\t"
 182     "pop         %es                \n\t"
 183     "popf                           \n\t"
 184     "popa                           \n\t"
 185     "leave                          \n\t"
 186     "ret                            \n\t"
 187     ".previous");
 188
 189
 190 /*
 191  *      cru_detect
 192  *
 193  *      Routine Description:
 194  *      This function uses the 32-bit BIOS Service Directory record to
 195  *      search for a $CRU record.
 196  *
 197  *      Return Value:
 198  *      0        :  SUCCESS
 199  *      <0       :  FAILURE
 200  */
 201 static int __devinit cru_detect(unsigned long map_entry,
 202         unsigned long map_offset)
 203 {
 204         void *bios32_map;
 205         unsigned long *bios32_entrypoint;
 206         unsigned long cru_physical_address;
 207         unsigned long cru_length;
 208         unsigned long physical_bios_base = 0;
 209         unsigned long physical_bios_offset = 0;
 210         int retval = -ENODEV;
 211
 212         bios32_map = ioremap(map_entry, (2 * PAGE_SIZE));
 213
 214         if (bios32_map == NULL)
 215                 return -ENODEV;
 216
 217         bios32_entrypoint = bios32_map + map_offset;
 218
 219         cmn_regs.u1.reax = CRU_BIOS_SIGNATURE_VALUE;
 220
 221         asminline_call(&cmn_regs, bios32_entrypoint);
 222
 223         if (cmn_regs.u1.ral != 0) {
 224                 printk(KERN_WARNING
 225                         "hpwdt: Call succeeded but with an error: 0x%x\n",
 226                         cmn_regs.u1.ral);
 227         } else {
 228                 physical_bios_base = cmn_regs.u2.rebx;
 229                 physical_bios_offset = cmn_regs.u4.redx;
 230                 cru_length = cmn_regs.u3.recx;
 231                 cru_physical_address =
 232                         physical_bios_base + physical_bios_offset;
 233
 234                 /* If the values look OK, then map it in. */
 235                 if ((physical_bios_base + physical_bios_offset)) {
 236                         cru_rom_addr =
 237                                 ioremap(cru_physical_address, cru_length);
 238                         if (cru_rom_addr)
 239                                 retval = 0;
 240                 }
 241
 242                 printk(KERN_DEBUG "hpwdt: CRU Base Address:   0x%lx\n",
 243                         physical_bios_base);
 244                 printk(KERN_DEBUG "hpwdt: CRU Offset Address: 0x%lx\n",
 245                         physical_bios_offset);
 246                 printk(KERN_DEBUG "hpwdt: CRU Length:         0x%lx\n",
 247                         cru_length);
 248                 printk(KERN_DEBUG "hpwdt: CRU Mapped Address: 0x%x\n",
 249                         (unsigned int)&cru_rom_addr);
 250         }
 251         iounmap(bios32_map);
 252         return retval;
 253 }
 254
 255 /*
 256  *      bios_checksum
 257  */
 258 static int __devinit bios_checksum(const char __iomem *ptr, int len)
 259 {
 260         char sum = 0;
 261         int i;
 262
 263         /*
 264          * calculate checksum of size bytes. This should add up
 265          * to zero if we have a valid header.
 266          */
 267         for (i = 0; i < len; i++)
 268                 sum += ptr[i];
 269
 270         return ((sum == 0) && (len > 0));
 271 }
 272
 273 /*
 274  *      bios32_present
 275  *
 276  *      Routine Description:
 277  *      This function finds the 32-bit BIOS Service Directory
 278  *
 279  *      Return Value:
 280  *      0        :  SUCCESS
 281  *      <0       :  FAILURE
 282  */
 283 static int __devinit bios32_present(const char __iomem *p)
 284 {
 285         struct bios32_service_dir *bios_32_ptr;
 286         int length;
 287         unsigned long map_entry, map_offset;
 288
 289         bios_32_ptr = (struct bios32_service_dir *) p;
 290
 291         /*
 292          * Search for signature by checking equal to the swizzled value
 293          * instead of calling another routine to perform a strcmp.
 294          */
 295         if (bios_32_ptr->signature == PCI_BIOS32_SD_VALUE) {
 296                 length = bios_32_ptr->length * PCI_BIOS32_PARAGRAPH_LEN;
 297                 if (bios_checksum(p, length)) {
 298                         /*
 299                          * According to the spec, we're looking for the
 300                          * first 4KB-aligned address below the entrypoint
 301                          * listed in the header. The Service Directory code
 302                          * is guaranteed to occupy no more than 2 4KB pages.
 303                          */
 304                         map_entry = bios_32_ptr->entry_point & ~(PAGE_SIZE - 1);
 305                         map_offset = bios_32_ptr->entry_point - map_entry;
 306
 307                         return cru_detect(map_entry, map_offset);
 308                 }
 309         }
 310         return -ENODEV;
 311 }
 312
 313 static int __devinit detect_cru_service(void)
 314 {
 315         char __iomem *p, *q;
 316         int rc = -1;
 317
 318         /*
 319          * Search from 0x0f0000 through 0x0fffff, inclusive.
 320          */
 321         p = ioremap(PCI_ROM_BASE1, ROM_SIZE);
 322         if (p == NULL)
 323                 return -ENOMEM;
 324
 325         for (q = p; q < p + ROM_SIZE; q += 16) {
 326                 rc = bios32_present(q);
 327                 if (!rc)
 328                         break;
 329         }
 330         iounmap(p);
 331         return rc;
 332 }
 333
 334 #else
 335 /* --64 Bit Bios------------------------------------------------------------ */
 336
 337 #define HPWDT_ARCH      64
 338
 339 asm(".text                      \n\t"
 340     ".align 4                   \n"
 341     "asminline_call:            \n\t"
 342     "pushq      %rbp            \n\t"
 343     "movq       %rsp, %rbp      \n\t"
 344     "pushq      %rax            \n\t"
 345     "pushq      %rbx            \n\t"
 346     "pushq      %rdx            \n\t"
 347     "pushq      %r12            \n\t"
 348     "pushq      %r9             \n\t"
 349     "movq       %rsi, %r12      \n\t"
 350     "movq       %rdi, %r9       \n\t"
 351     "movl       4(%r9),%ebx     \n\t"
 352     "movl       8(%r9),%ecx     \n\t"
 353     "movl       12(%r9),%edx    \n\t"
 354     "movl       16(%r9),%esi    \n\t"
 355     "movl       20(%r9),%edi    \n\t"
 356     "movl       (%r9),%eax      \n\t"
 357     "call       *%r12           \n\t"
 358     "pushfq                     \n\t"
 359     "popq        %r12           \n\t"
 360     "movl       %eax, (%r9)     \n\t"
 361     "movl       %ebx, 4(%r9)    \n\t"
 362     "movl       %ecx, 8(%r9)    \n\t"
 363     "movl       %edx, 12(%r9)   \n\t"
 364     "movl       %esi, 16(%r9)   \n\t"
 365     "movl       %edi, 20(%r9)   \n\t"
 366     "movq       %r12, %rax      \n\t"
 367     "movl       %eax, 28(%r9)   \n\t"
 368     "popq       %r9             \n\t"
 369     "popq       %r12            \n\t"
 370     "popq       %rdx            \n\t"
 371     "popq       %rbx            \n\t"
 372     "popq       %rax            \n\t"
 373     "leave                      \n\t"
 374     "ret                        \n\t"
 375     ".previous");
 376
 377 /*
 378  *      dmi_find_cru
 379  *
 380  *      Routine Description:
 381  *      This function checks whether or not a SMBIOS/DMI record is
 382  *      the 64bit CRU info or not
 383  */
 384 static void __devinit dmi_find_cru(const struct dmi_header *dm)
 385 {
 386         struct smbios_cru64_info *smbios_cru64_ptr;
 387         unsigned long cru_physical_address;
 388
 389         if (dm->type == SMBIOS_CRU64_INFORMATION) {
 390                 smbios_cru64_ptr = (struct smbios_cru64_info *) dm;
 391                 if (smbios_cru64_ptr->signature == CRU_BIOS_SIGNATURE_VALUE) {
 392                         cru_physical_address =
 393                                 smbios_cru64_ptr->physical_address +
 394                                 smbios_cru64_ptr->double_offset;
 395                         cru_rom_addr = ioremap(cru_physical_address,
 396                                 smbios_cru64_ptr->double_length);
 397                 }
 398         }
 399 }
 400
 401 static int __devinit detect_cru_service(void)
 402 {
 403         cru_rom_addr = NULL;
 404
 405         dmi_walk(dmi_find_cru);
 406
 407         /* if cru_rom_addr has been set then we found a CRU service */
 408         return ((cru_rom_addr != NULL) ? 0 : -ENODEV);
 409 }
 410
 411 /* ------------------------------------------------------------------------- */
 412
 413 #endif
 414
 415 /*
 416  *      Watchdog operations
 417  */
 418 static void hpwdt_start(void)
 419 {
 420         reload = (soft_margin * 1000) / 128;
 421         iowrite16(reload, hpwdt_timer_reg);
 422         iowrite16(0x85, hpwdt_timer_con);
 423 }
 424
 425 static void hpwdt_stop(void)
 426 {
 427         unsigned long data;
 428
 429         data = ioread16(hpwdt_timer_con);
 430         data &= 0xFE;
 431         iowrite16(data, hpwdt_timer_con);
 432 }
 433
 434 static void hpwdt_ping(void)
 435 {
 436         iowrite16(reload, hpwdt_timer_reg);
 437 }
 438
 439 static int hpwdt_change_timer(int new_margin)
 440 {
 441         /* Arbitrary, can't find the card's limits */
 442         if (new_margin < 30 || new_margin > 600) {
 443                 printk(KERN_WARNING
 444                         "hpwdt: New value passed in is invalid: %d seconds.\n",
 445                         new_margin);
 446                 return -EINVAL;
 447         }
 448
 449         soft_margin = new_margin;
 450         printk(KERN_DEBUG
 451                 "hpwdt: New timer passed in is %d seconds.\n",
 452                 new_margin);
 453         reload = (soft_margin * 1000) / 128;
 454
 455         return 0;
 456 }
 457
 458 /*
 459  *      NMI Handler
 460  */
 461 static int hpwdt_pretimeout(struct notifier_block *nb, unsigned long ulReason,
 462                                 void *data)
 463 {
 464         unsigned long rom_pl;
 465         static int die_nmi_called;
 466
 467         if (ulReason != DIE_NMI && ulReason != DIE_NMI_IPI)
 468                 return NOTIFY_OK;
 469
 470         spin_lock_irqsave(&rom_lock, rom_pl);
 471         if (!die_nmi_called)
 472                 asminline_call(&cmn_regs, cru_rom_addr);
 473         die_nmi_called = 1;
 474         spin_unlock_irqrestore(&rom_lock, rom_pl);
 475         if (cmn_regs.u1.ral == 0) {
 476                 printk(KERN_WARNING "hpwdt: An NMI occurred, "
 477                         "but unable to determine source.\n");
 478         } else {
 479                 if (allow_kdump)
 480                         hpwdt_stop();
 481                 panic("An NMI occurred, please see the Integrated "
 482                         "Management Log for details.\n");
 483         }
 484
 485         return NOTIFY_STOP;
 486 }
 487
 488 /*
 489  *      /dev/watchdog handling
 490  */
 491 static int hpwdt_open(struct inode *inode, struct file *file)
 492 {
 493         /* /dev/watchdog can only be opened once */
 494         if (test_and_set_bit(0, &hpwdt_is_open))
 495                 return -EBUSY;
 496
 497         /* Start the watchdog */
 498         hpwdt_start();
 499         hpwdt_ping();
 500
 501         return nonseekable_open(inode, file);
 502 }
 503
 504 static int hpwdt_release(struct inode *inode, struct file *file)
 505 {
 506         /* Stop the watchdog */
 507         if (expect_release == 42) {
 508                 hpwdt_stop();
 509         } else {
 510                 printk(KERN_CRIT
 511                         "hpwdt: Unexpected close, not stopping watchdog!\n");
 512                 hpwdt_ping();
 513         }
 514
 515         expect_release = 0;
 516
 517         /* /dev/watchdog is being closed, make sure it can be re-opened */
 518         clear_bit(0, &hpwdt_is_open);
 519
 520         return 0;
 521 }
 522
 523 static ssize_t hpwdt_write(struct file *file, const char __user *data,
 524         size_t len, loff_t *ppos)
 525 {
 526         /* See if we got the magic character 'V' and reload the timer */
 527         if (len) {
 528                 if (!nowayout) {
 529                         size_t i;
 530
 531                         /* note: just in case someone wrote the magic character
 532                          * five months ago... */
 533                         expect_release = 0;
 534
 535                         /* scan to see whether or not we got the magic char. */
 536                         for (i = 0; i != len; i++) {
 537                                 char c;
 538                                 if (get_user(c, data + i))
 539                                         return -EFAULT;
 540                                 if (c == 'V')
 541                                         expect_release = 42;
 542                         }
 543                 }
 544
 545                 /* someone wrote to us, we should reload the timer */
 546                 hpwdt_ping();
 547         }
 548
 549         return len;
 550 }
 551
 552 static struct watchdog_info ident = {
 553         .options = WDIOF_SETTIMEOUT |
 554                    WDIOF_KEEPALIVEPING |
 555                    WDIOF_MAGICCLOSE,
 556         .identity = "HP iLO2 HW Watchdog Timer",
 557 };
 558
 559 static long hpwdt_ioctl(struct file *file, unsigned int cmd,
 560         unsigned long arg)
 561 {
 562         void __user *argp = (void __user *)arg;
 563         int __user *p = argp;
 564         int new_margin;
 565         int ret = -ENOTTY;
 566
 567         switch (cmd) {
 568         case WDIOC_GETSUPPORT:
 569                 ret = 0;
 570                 if (copy_to_user(argp, &ident, sizeof(ident)))
 571                         ret = -EFAULT;
 572                 break;
 573
 574         case WDIOC_GETSTATUS:
 575         case WDIOC_GETBOOTSTATUS:
 576                 ret = put_user(0, p);
 577                 break;
 578
 579         case WDIOC_KEEPALIVE:
 580                 hpwdt_ping();
 581                 ret = 0;
 582                 break;
 583
 584         case WDIOC_SETTIMEOUT:
 585                 ret = get_user(new_margin, p);
 586                 if (ret)
 587                         break;
 588
 589                 ret = hpwdt_change_timer(new_margin);
 590                 if (ret)
 591                         break;
 592
 593                 hpwdt_ping();
 594                 /* Fall */
 595         case WDIOC_GETTIMEOUT:
 596                 ret = put_user(soft_margin, p);
 597                 break;
 598         }
 599         return ret;
 600 }
 601
 602 /*
 603  *      Kernel interfaces
 604  */
 605 static struct file_operations hpwdt_fops = {
 606         .owner = THIS_MODULE,
 607         .llseek = no_llseek,
 608         .write = hpwdt_write,
 609         .unlocked_ioctl = hpwdt_ioctl,
 610         .open = hpwdt_open,
 611         .release = hpwdt_release,
 612 };
 613
 614 static struct miscdevice hpwdt_miscdev = {
 615         .minor = WATCHDOG_MINOR,
 616         .name = "watchdog",
 617         .fops = &hpwdt_fops,
 618 };
 619
 620 static struct notifier_block die_notifier = {
 621         .notifier_call = hpwdt_pretimeout,
 622         .priority = 0x7FFFFFFF,
 623 };
 624
 625 /*
 626  *      Init & Exit
 627  */
 628
 629 static int __devinit hpwdt_init_one(struct pci_dev *dev,
 630                                         const struct pci_device_id *ent)
 631 {
 632         int retval;
 633
 634         /*
 635          * First let's find out if we are on an iLO2 server. We will
 636          * not run on a legacy ASM box.
 637          * So we only support the G5 ProLiant servers and higher.
 638          */
 639         if (dev->subsystem_vendor != PCI_VENDOR_ID_HP) {
 640                 dev_warn(&dev->dev,
 641                         "This server does not have an iLO2 ASIC.\n");
 642                 return -ENODEV;
 643         }
 644
 645         if (pci_enable_device(dev)) {
 646                 dev_warn(&dev->dev,
 647                         "Not possible to enable PCI Device: 0x%x:0x%x.\n",
 648                         ent->vendor, ent->device);
 649                 return -ENODEV;
 650         }
 651
 652         pci_mem_addr = pci_iomap(dev, 1, 0x80);
 653         if (!pci_mem_addr) {
 654                 dev_warn(&dev->dev,
 655                         "Unable to detect the iLO2 server memory.\n");
 656                 retval = -ENOMEM;
 657                 goto error_pci_iomap;
 658         }
 659         hpwdt_timer_reg = pci_mem_addr + 0x70;
 660         hpwdt_timer_con = pci_mem_addr + 0x72;
 661
 662         /* Make sure that we have a valid soft_margin */
 663         if (hpwdt_change_timer(soft_margin))
 664                 hpwdt_change_timer(DEFAULT_MARGIN);
 665
 666         /*
 667          * We need to map the ROM to get the CRU service.
 668          * For 32 bit Operating Systems we need to go through the 32 Bit
 669          * BIOS Service Directory
 670          * For 64 bit Operating Systems we get that service through SMBIOS.
 671          */
 672         retval = detect_cru_service();
 673         if (retval < 0) {
 674                 dev_warn(&dev->dev,
 675                         "Unable to detect the %d Bit CRU Service.\n",
 676                         HPWDT_ARCH);
 677                 goto error_get_cru;
 678         }
 679
 680         /*
 681          * We know this is the only CRU call we need to make so lets keep as
 682          * few instructions as possible once the NMI comes in.
 683          */
 684         cmn_regs.u1.rah = 0x0D;
 685         cmn_regs.u1.ral = 0x02;
 686
 687         retval = register_die_notifier(&die_notifier);
 688         if (retval != 0) {
 689                 dev_warn(&dev->dev,
 690                         "Unable to register a die notifier (err=%d).\n",
 691                         retval);
 692                 goto error_die_notifier;
 693         }
 694
 695         retval = misc_register(&hpwdt_miscdev);
 696         if (retval < 0) {
 697                 dev_warn(&dev->dev,
 698                         "Unable to register miscdev on minor=%d (err=%d).\n",
 699                         WATCHDOG_MINOR, retval);
 700                 goto error_misc_register;
 701         }
 702
 703         printk(KERN_INFO
 704                 "hp Watchdog Timer Driver: 1.00"
 705                 ", timer margin: %d seconds (nowayout=%d)"
 706                 ", allow kernel dump: %s (default = 0/OFF).\n",
 707                 soft_margin, nowayout, (allow_kdump == 0) ? "OFF" : "ON");
 708
 709         return 0;
 710
 711 error_misc_register:
 712         unregister_die_notifier(&die_notifier);
 713 error_die_notifier:
 714         if (cru_rom_addr)
 715                 iounmap(cru_rom_addr);
 716 error_get_cru:
 717         pci_iounmap(dev, pci_mem_addr);
 718 error_pci_iomap:
 719         pci_disable_device(dev);
 720         return retval;
 721 }
 722
 723 static void __devexit hpwdt_exit(struct pci_dev *dev)
 724 {
 725         if (!nowayout)
 726                 hpwdt_stop();
 727
 728         misc_deregister(&hpwdt_miscdev);
 729         unregister_die_notifier(&die_notifier);
 730
 731         if (cru_rom_addr)
 732                 iounmap(cru_rom_addr);
 733         pci_iounmap(dev, pci_mem_addr);
 734         pci_disable_device(dev);
 735 }
 736
 737 static struct pci_driver hpwdt_driver = {
 738         .name = "hpwdt",
 739         .id_table = hpwdt_devices,
 740         .probe = hpwdt_init_one,
 741         .remove = __devexit_p(hpwdt_exit),
 742 };
 743
 744 static void __exit hpwdt_cleanup(void)
 745 {
 746         pci_unregister_driver(&hpwdt_driver);
 747 }
 748
 749 static int __init hpwdt_init(void)
 750 {
 751         return pci_register_driver(&hpwdt_driver);
 752 }
 753
 754 MODULE_AUTHOR("Tom Mingarelli");
 755 MODULE_DESCRIPTION("hp watchdog driver");
 756 MODULE_LICENSE("GPL");
 757 MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
 758
 759 module_param(soft_margin, int, 0);
 760 MODULE_PARM_DESC(soft_margin, "Watchdog timeout in seconds");
 761
 762 module_param(allow_kdump, int, 0);
 763 MODULE_PARM_DESC(allow_kdump, "Start a kernel dump after NMI occurs");
 764
 765 module_param(nowayout, int, 0);
 766 MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
 767                 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
 768
 769 module_init(hpwdt_init);
 770 module_exit(hpwdt_cleanup);