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/dmi.h>
  43 #include <asm/desc.h>
  44 #include <asm/kdebug.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
  52 struct bios32_service_dir {
  53         u32 signature;
  54         u32 entry_point;
  55         u8 revision;
  56         u8 length;
  57         u8 checksum;
  58         u8 reserved[5];
  59 };
  60
  61 /* type 212 */
  62 struct smbios_cru64_info {
  63         u8 type;
  64         u8 byte_length;
  65         u16 handle;
  66         u32 signature;
  67         u64 physical_address;
  68         u32 double_length;
  69         u32 double_offset;
  70 };
  71 #define SMBIOS_CRU64_INFORMATION        212
  72
  73 struct cmn_registers {
  74         union {
  75                 struct {
  76                         u8 ral;
  77                         u8 rah;
  78                         u16 rea2;
  79                 };
  80                 u32 reax;
  81         } u1;
  82         union {
  83                 struct {
  84                         u8 rbl;
  85                         u8 rbh;
  86                         u8 reb2l;
  87                         u8 reb2h;
  88                 };
  89                 u32 rebx;
  90         } u2;
  91         union {
  92                 struct {
  93                         u8 rcl;
  94                         u8 rch;
  95                         u16 rec2;
  96                 };
  97                 u32 recx;
  98         } u3;
  99         union {
 100                 struct {
 101                         u8 rdl;
 102                         u8 rdh;
 103                         u16 red2;
 104                 };
 105                 u32 redx;
 106         } u4;
 107
 108         u32 resi;
 109         u32 redi;
 110         u16 rds;
 111         u16 res;
 112         u32 reflags;
 113 }  __attribute__((packed));
 114
 115 #define DEFAULT_MARGIN  30
 116 static unsigned int soft_margin = DEFAULT_MARGIN;       /* in seconds */
 117 static unsigned int reload;                     /* the computed soft_margin */
 118 static int nowayout = WATCHDOG_NOWAYOUT;
 119 static char expect_release;
 120 static unsigned long hpwdt_is_open;
 121
 122 static void __iomem *pci_mem_addr;              /* the PCI-memory address */
 123 static unsigned long __iomem *hpwdt_timer_reg;
 124 static unsigned long __iomem *hpwdt_timer_con;
 125
 126 static DEFINE_SPINLOCK(rom_lock);
 127
 128 static void *cru_rom_addr;
 129
 130 static struct cmn_registers cmn_regs;
 131
 132 static struct pci_device_id hpwdt_devices[] = {
 133         {
 134          .vendor = PCI_VENDOR_ID_COMPAQ,
 135          .device = 0xB203,
 136          .subvendor = PCI_ANY_ID,
 137          .subdevice = PCI_ANY_ID,
 138         },
 139         {0},                    /* terminate list */
 140 };
 141 MODULE_DEVICE_TABLE(pci, hpwdt_devices);
 142
 143 extern asmlinkage void asminline_call(struct cmn_registers *pi86Regs, unsigned long *pRomEntry);
 144
 145 #ifndef CONFIG_X86_64
 146 /* --32 Bit Bios------------------------------------------------------------ */
 147
 148 #define HPWDT_ARCH      32
 149
 150 asm(".text                          \n\t"
 151     ".align 4                       \n"
 152     "asminline_call:                \n\t"
 153     "pushl       %ebp               \n\t"
 154     "movl        %esp, %ebp         \n\t"
 155     "pusha                          \n\t"
 156     "pushf                          \n\t"
 157     "push        %es                \n\t"
 158     "push        %ds                \n\t"
 159     "pop         %es                \n\t"
 160     "movl        8(%ebp),%eax       \n\t"
 161     "movl        4(%eax),%ebx       \n\t"
 162     "movl        8(%eax),%ecx       \n\t"
 163     "movl        12(%eax),%edx      \n\t"
 164     "movl        16(%eax),%esi      \n\t"
 165     "movl        20(%eax),%edi      \n\t"
 166     "movl        (%eax),%eax        \n\t"
 167     "push        %cs                \n\t"
 168     "call        *12(%ebp)          \n\t"
 169     "pushf                          \n\t"
 170     "pushl       %eax               \n\t"
 171     "movl        8(%ebp),%eax       \n\t"
 172     "movl        %ebx,4(%eax)       \n\t"
 173     "movl        %ecx,8(%eax)       \n\t"
 174     "movl        %edx,12(%eax)      \n\t"
 175     "movl        %esi,16(%eax)      \n\t"
 176     "movl        %edi,20(%eax)      \n\t"
 177     "movw        %ds,24(%eax)       \n\t"
 178     "movw        %es,26(%eax)       \n\t"
 179     "popl        %ebx               \n\t"
 180     "movl        %ebx,(%eax)        \n\t"
 181     "popl        %ebx               \n\t"
 182     "movl        %ebx,28(%eax)      \n\t"
 183     "pop         %es                \n\t"
 184     "popf                           \n\t"
 185     "popa                           \n\t"
 186     "leave                          \n\t"
 187     "ret                            \n\t"
 188     ".previous");
 189
 190
 191 /*
 192  *      cru_detect
 193  *
 194  *      Routine Description:
 195  *      This function uses the 32-bit BIOS Service Directory record to
 196  *      search for a $CRU record.
 197  *
 198  *      Return Value:
 199  *      0        :  SUCCESS
 200  *      <0       :  FAILURE
 201  */
 202 static int __devinit cru_detect(unsigned long map_entry,
 203         unsigned long map_offset)
 204 {
 205         void *bios32_map;
 206         unsigned long *bios32_entrypoint;
 207         unsigned long cru_physical_address;
 208         unsigned long cru_length;
 209         unsigned long physical_bios_base = 0;
 210         unsigned long physical_bios_offset = 0;
 211         int retval = -ENODEV;
 212
 213         bios32_map = ioremap(map_entry, (2 * PAGE_SIZE));
 214
 215         if (bios32_map == NULL)
 216                 return -ENODEV;
 217
 218         bios32_entrypoint = bios32_map + map_offset;
 219
 220         cmn_regs.u1.reax = CRU_BIOS_SIGNATURE_VALUE;
 221
 222         asminline_call(&cmn_regs, bios32_entrypoint);
 223
 224         if (cmn_regs.u1.ral != 0) {
 225                 printk(KERN_WARNING
 226                        "hpwdt: Call succeeded but with an error: 0x%x\n",
 227                        cmn_regs.u1.ral);
 228         } else {
 229                 physical_bios_base = cmn_regs.u2.rebx;
 230                 physical_bios_offset = cmn_regs.u4.redx;
 231                 cru_length = cmn_regs.u3.recx;
 232                 cru_physical_address =
 233                     physical_bios_base + physical_bios_offset;
 234
 235                 /* If the values look OK, then map it in. */
 236                 if ((physical_bios_base + physical_bios_offset)) {
 237                         cru_rom_addr =
 238                             ioremap(cru_physical_address, cru_length);
 239                         if (cru_rom_addr)
 240                                 retval = 0;
 241                 }
 242
 243                 printk(KERN_DEBUG "hpwdt: CRU Base Address:   0x%lx\n",
 244                         physical_bios_base);
 245                 printk(KERN_DEBUG "hpwdt: CRU Offset Address: 0x%lx\n",
 246                         physical_bios_offset);
 247                 printk(KERN_DEBUG "hpwdt: CRU Length:         0x%lx\n",
 248                         cru_length);
 249                 printk(KERN_DEBUG "hpwdt: CRU Mapped Address: 0x%x\n",
 250                         (unsigned int)&cru_rom_addr);
 251         }
 252         iounmap(bios32_map);
 253         return retval;
 254 }
 255
 256 /*
 257  *      bios_checksum
 258  */
 259 static int __devinit bios_checksum(const char __iomem *ptr, int len)
 260 {
 261         char sum = 0;
 262         int i;
 263
 264         /*
 265          * calculate checksum of size bytes. This should add up
 266          * to zero if we have a valid header.
 267          */
 268         for (i = 0; i < len; i++)
 269                 sum += ptr[i];
 270
 271         return ((sum == 0) && (len > 0));
 272 }
 273
 274 /*
 275  *      bios32_present
 276  *
 277  *      Routine Description:
 278  *      This function finds the 32-bit BIOS Service Directory
 279  *
 280  *      Return Value:
 281  *      0        :  SUCCESS
 282  *      <0       :  FAILURE
 283  */
 284 static int __devinit bios32_present(const char __iomem *p)
 285 {
 286         struct bios32_service_dir *bios_32_ptr;
 287         int length;
 288         unsigned long map_entry, map_offset;
 289
 290         bios_32_ptr = (struct bios32_service_dir *) p;
 291
 292         /*
 293          * Search for signature by checking equal to the swizzled value
 294          * instead of calling another routine to perform a strcmp.
 295          */
 296         if (bios_32_ptr->signature == PCI_BIOS32_SD_VALUE) {
 297                 length = bios_32_ptr->length * PCI_BIOS32_PARAGRAPH_LEN;
 298                 if (bios_checksum(p, length)) {
 299                         /*
 300                          * According to the spec, we're looking for the
 301                          * first 4KB-aligned address below the entrypoint
 302                          * listed in the header. The Service Directory code
 303                          * is guaranteed to occupy no more than 2 4KB pages.
 304                          */
 305                         map_entry = bios_32_ptr->entry_point & ~(PAGE_SIZE - 1);
 306                         map_offset = bios_32_ptr->entry_point - map_entry;
 307
 308                         return cru_detect(map_entry, map_offset);
 309                 }
 310         }
 311         return -ENODEV;
 312 }
 313
 314 static int __devinit detect_cru_service(void)
 315 {
 316         char __iomem *p, *q;
 317         int rc = -1;
 318
 319         /*
 320          * Search from 0x0f0000 through 0x0fffff, inclusive.
 321          */
 322         p = ioremap(PCI_ROM_BASE1, ROM_SIZE);
 323         if (p == NULL)
 324                 return -ENOMEM;
 325
 326         for (q = p; q < p + ROM_SIZE; q += 16) {
 327                 rc = bios32_present(q);
 328                 if (!rc)
 329                         break;
 330         }
 331         iounmap(p);
 332         return rc;
 333 }
 334
 335 #else
 336 /* --64 Bit Bios------------------------------------------------------------ */
 337
 338 #define HPWDT_ARCH      64
 339
 340 asm(".text                      \n\t"
 341     ".align 4                   \n"
 342     "asminline_call:            \n\t"
 343     "pushq      %rbp            \n\t"
 344     "movq       %rsp, %rbp      \n\t"
 345     "pushq      %rax            \n\t"
 346     "pushq      %rbx            \n\t"
 347     "pushq      %rdx            \n\t"
 348     "pushq      %r12            \n\t"
 349     "pushq      %r9             \n\t"
 350     "movq       %rsi, %r12      \n\t"
 351     "movq       %rdi, %r9       \n\t"
 352     "movl       4(%r9),%ebx     \n\t"
 353     "movl       8(%r9),%ecx     \n\t"
 354     "movl       12(%r9),%edx    \n\t"
 355     "movl       16(%r9),%esi    \n\t"
 356     "movl       20(%r9),%edi    \n\t"
 357     "movl       (%r9),%eax      \n\t"
 358     "call       *%r12           \n\t"
 359     "pushfq                     \n\t"
 360     "popq        %r12           \n\t"
 361     "popfq                      \n\t"
 362     "movl       %eax, (%r9)     \n\t"
 363     "movl       %ebx, 4(%r9)    \n\t"
 364     "movl       %ecx, 8(%r9)    \n\t"
 365     "movl       %edx, 12(%r9)   \n\t"
 366     "movl       %esi, 16(%r9)   \n\t"
 367     "movl       %edi, 20(%r9)   \n\t"
 368     "movq       %r12, %rax      \n\t"
 369     "movl       %eax, 28(%r9)   \n\t"
 370     "popq       %r9             \n\t"
 371     "popq       %r12            \n\t"
 372     "popq       %rdx            \n\t"
 373     "popq       %rbx            \n\t"
 374     "popq       %rax            \n\t"
 375     "leave                      \n\t"
 376     "ret                        \n\t"
 377     ".previous");
 378
 379 /*
 380  *      dmi_find_cru
 381  *
 382  *      Routine Description:
 383  *      This function checks whether or not a SMBIOS/DMI record is
 384  *      the 64bit CRU info or not
 385  */
 386 static void __devinit dmi_find_cru(const struct dmi_header *dm)
 387 {
 388         struct smbios_cru64_info *smbios_cru64_ptr;
 389         unsigned long cru_physical_address;
 390
 391         if (dm->type == SMBIOS_CRU64_INFORMATION) {
 392                 smbios_cru64_ptr = (struct smbios_cru64_info *) dm;
 393                 if (smbios_cru64_ptr->signature == CRU_BIOS_SIGNATURE_VALUE) {
 394                         cru_physical_address =
 395                             smbios_cru64_ptr->physical_address +
 396                             smbios_cru64_ptr->double_offset;
 397                         cru_rom_addr = ioremap(cru_physical_address,
 398                                     smbios_cru64_ptr->double_length);
 399                 }
 400         }
 401 }
 402
 403 static int __devinit detect_cru_service(void)
 404 {
 405         cru_rom_addr = NULL;
 406
 407         dmi_walk(dmi_find_cru);
 408
 409         /* if cru_rom_addr has been set then we found a CRU service */
 410         return ((cru_rom_addr != NULL)? 0: -ENODEV);
 411 }
 412
 413 /* ------------------------------------------------------------------------- */
 414
 415 #endif
 416
 417 /*
 418  *      NMI Handler
 419  */
 420 static int hpwdt_pretimeout(struct notifier_block *nb, unsigned long ulReason,
 421                             void *data)
 422 {
 423         unsigned long rom_pl;
 424         static int die_nmi_called;
 425
 426         if (ulReason != DIE_NMI && ulReason != DIE_NMI_IPI)
 427                 return NOTIFY_OK;
 428
 429         spin_lock_irqsave(&rom_lock, rom_pl);
 430         if (!die_nmi_called)
 431                 asminline_call(&cmn_regs, cru_rom_addr);
 432         die_nmi_called = 1;
 433         spin_unlock_irqrestore(&rom_lock, rom_pl);
 434         if (cmn_regs.u1.ral == 0) {
 435                 printk(KERN_WARNING "hpwdt: An NMI occurred, "
 436                        "but unable to determine source.\n");
 437         } else {
 438                 panic("An NMI occurred, please see the Integrated "
 439                         "Management Log for details.\n");
 440         }
 441
 442         return NOTIFY_STOP;
 443 }
 444
 445 /*
 446  *      Watchdog operations
 447  */
 448 static void hpwdt_start(void)
 449 {
 450         reload = (soft_margin * 1000) / 128;
 451         iowrite16(reload, hpwdt_timer_reg);
 452         iowrite16(0x85, hpwdt_timer_con);
 453 }
 454
 455 static void hpwdt_stop(void)
 456 {
 457         unsigned long data;
 458
 459         data = ioread16(hpwdt_timer_con);
 460         data &= 0xFE;
 461         iowrite16(data, hpwdt_timer_con);
 462 }
 463
 464 static void hpwdt_ping(void)
 465 {
 466         iowrite16(reload, hpwdt_timer_reg);
 467 }
 468
 469 static int hpwdt_change_timer(int new_margin)
 470 {
 471         /* Arbitrary, can't find the card's limits */
 472         if (new_margin < 30 || new_margin > 600) {
 473                 printk(KERN_WARNING
 474                         "hpwdt: New value passed in is invalid: %d seconds.\n",
 475                         new_margin);
 476                 return -EINVAL;
 477         }
 478
 479         soft_margin = new_margin;
 480         printk(KERN_DEBUG
 481                 "hpwdt: New timer passed in is %d seconds.\n",
 482                 new_margin);
 483         reload = (soft_margin * 1000) / 128;
 484
 485         return 0;
 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          */
 638         if (dev->subsystem_vendor != PCI_VENDOR_ID_HP) {
 639                 dev_warn(&dev->dev,
 640                        "This server does not have an iLO2 ASIC.\n");
 641                 return -ENODEV;
 642         }
 643
 644         if (pci_enable_device(dev)) {
 645                 dev_warn(&dev->dev,
 646                         "Not possible to enable PCI Device: 0x%x:0x%x.\n",
 647                         ent->vendor, ent->device);
 648                 return -ENODEV;
 649         }
 650
 651         pci_mem_addr = pci_iomap(dev, 1, 0x80);
 652         if (!pci_mem_addr) {
 653                 dev_warn(&dev->dev,
 654                         "Unable to detect the iLO2 server memory.\n");
 655                 retval = -ENOMEM;
 656                 goto error_pci_iomap;
 657         }
 658         hpwdt_timer_reg = pci_mem_addr + 0x70;
 659         hpwdt_timer_con = pci_mem_addr + 0x72;
 660
 661         /* Make sure that we have a valid soft_margin */
 662         if (hpwdt_change_timer(soft_margin))
 663                 hpwdt_change_timer(DEFAULT_MARGIN);
 664
 665         /*
 666          * We need to map the ROM to get the CRU service.
 667          * For 32 bit Operating Systems we need to go through the 32 Bit
 668          * BIOS Service Directory
 669          * For 64 bit Operating Systems we get that service through SMBIOS.
 670          */
 671         retval = detect_cru_service();
 672         if (retval < 0) {
 673                 dev_warn(&dev->dev,
 674                        "Unable to detect the %d Bit CRU Service.\n",
 675                         HPWDT_ARCH);
 676                 goto error_get_cru;
 677         }
 678
 679         /*
 680          * We know this is the only CRU call we need to make so lets keep as
 681          * few instructions as possible once the NMI comes in.
 682          */
 683         cmn_regs.u1.rah = 0x0D;
 684         cmn_regs.u1.ral = 0x02;
 685
 686         retval = register_die_notifier(&die_notifier);
 687         if (retval != 0) {
 688                 dev_warn(&dev->dev,
 689                        "Unable to register a die notifier (err=%d).\n",
 690                         retval);
 691                 goto error_die_notifier;
 692         }
 693
 694         retval = misc_register(&hpwdt_miscdev);
 695         if (retval < 0) {
 696                 dev_warn(&dev->dev,
 697                         "Unable to register miscdev on minor=%d (err=%d).\n",
 698                         WATCHDOG_MINOR, retval);
 699                 goto error_misc_register;
 700         }
 701
 702         printk(KERN_INFO
 703                 "hp Watchdog Timer Driver: 1.00"
 704                 ", timer margin: %d seconds( nowayout=%d).\n",
 705                 soft_margin, nowayout);
 706
 707         return 0;
 708
 709 error_misc_register:
 710         unregister_die_notifier(&die_notifier);
 711 error_die_notifier:
 712         if (cru_rom_addr)
 713                 iounmap(cru_rom_addr);
 714 error_get_cru:
 715         pci_iounmap(dev, pci_mem_addr);
 716 error_pci_iomap:
 717         pci_disable_device(dev);
 718         return retval;
 719 }
 720
 721 static void __devexit hpwdt_exit(struct pci_dev *dev)
 722 {
 723         if (!nowayout)
 724                 hpwdt_stop();
 725
 726         misc_deregister(&hpwdt_miscdev);
 727         unregister_die_notifier(&die_notifier);
 728
 729         if (cru_rom_addr)
 730                 iounmap(cru_rom_addr);
 731         pci_iounmap(dev, pci_mem_addr);
 732         pci_disable_device(dev);
 733 }
 734
 735 static struct pci_driver hpwdt_driver = {
 736         .name = "hpwdt",
 737         .id_table = hpwdt_devices,
 738         .probe = hpwdt_init_one,
 739         .remove = __devexit_p(hpwdt_exit),
 740 };
 741
 742 static void __exit hpwdt_cleanup(void)
 743 {
 744         pci_unregister_driver(&hpwdt_driver);
 745 }
 746
 747 static int __init hpwdt_init(void)
 748 {
 749         return pci_register_driver(&hpwdt_driver);
 750 }
 751
 752 MODULE_AUTHOR("Tom Mingarelli");
 753 MODULE_DESCRIPTION("hp watchdog driver");
 754 MODULE_LICENSE("GPL");
 755 MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
 756
 757 module_param(soft_margin, int, 0);
 758 MODULE_PARM_DESC(soft_margin, "Watchdog timeout in seconds");
 759
 760 module_param(nowayout, int, 0);
 761 MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
 762                 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
 763
 764 module_init(hpwdt_init);
 765 module_exit(hpwdt_cleanup);