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