Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/linux-arm-soc
[pandora-kernel.git] / 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/bitops.h>
21 #include <linux/kernel.h>
22 #include <linux/miscdevice.h>
23 #include <linux/module.h>
24 #include <linux/moduleparam.h>
25 #include <linux/pci.h>
26 #include <linux/pci_ids.h>
27 #include <linux/types.h>
28 #include <linux/uaccess.h>
29 #include <linux/watchdog.h>
30 #ifdef CONFIG_HPWDT_NMI_DECODING
31 #include <linux/dmi.h>
32 #include <linux/spinlock.h>
33 #include <linux/nmi.h>
34 #include <linux/kdebug.h>
35 #include <linux/notifier.h>
36 #include <asm/cacheflush.h>
37 #endif /* CONFIG_HPWDT_NMI_DECODING */
38
39 #define HPWDT_VERSION                   "1.3.0"
40 #define SECS_TO_TICKS(secs)             ((secs) * 1000 / 128)
41 #define TICKS_TO_SECS(ticks)            ((ticks) * 128 / 1000)
42 #define HPWDT_MAX_TIMER                 TICKS_TO_SECS(65535)
43 #define DEFAULT_MARGIN                  30
44
45 static unsigned int soft_margin = DEFAULT_MARGIN;       /* in seconds */
46 static unsigned int reload;                     /* the computed soft_margin */
47 static int nowayout = WATCHDOG_NOWAYOUT;
48 static char expect_release;
49 static unsigned long hpwdt_is_open;
50
51 static void __iomem *pci_mem_addr;              /* the PCI-memory address */
52 static unsigned long __iomem *hpwdt_timer_reg;
53 static unsigned long __iomem *hpwdt_timer_con;
54
55 static DEFINE_PCI_DEVICE_TABLE(hpwdt_devices) = {
56         { PCI_DEVICE(PCI_VENDOR_ID_COMPAQ, 0xB203) },   /* iLO2 */
57         { PCI_DEVICE(PCI_VENDOR_ID_HP, 0x3306) },       /* iLO3 */
58         {0},                    /* terminate list */
59 };
60 MODULE_DEVICE_TABLE(pci, hpwdt_devices);
61
62 #ifdef CONFIG_HPWDT_NMI_DECODING
63 #define PCI_BIOS32_SD_VALUE             0x5F32335F      /* "_32_" */
64 #define CRU_BIOS_SIGNATURE_VALUE        0x55524324
65 #define PCI_BIOS32_PARAGRAPH_LEN        16
66 #define PCI_ROM_BASE1                   0x000F0000
67 #define ROM_SIZE                        0x10000
68
69 struct bios32_service_dir {
70         u32 signature;
71         u32 entry_point;
72         u8 revision;
73         u8 length;
74         u8 checksum;
75         u8 reserved[5];
76 };
77
78 /* type 212 */
79 struct smbios_cru64_info {
80         u8 type;
81         u8 byte_length;
82         u16 handle;
83         u32 signature;
84         u64 physical_address;
85         u32 double_length;
86         u32 double_offset;
87 };
88 #define SMBIOS_CRU64_INFORMATION        212
89
90 /* type 219 */
91 struct smbios_proliant_info {
92         u8 type;
93         u8 byte_length;
94         u16 handle;
95         u32 power_features;
96         u32 omega_features;
97         u32 reserved;
98         u32 misc_features;
99 };
100 #define SMBIOS_ICRU_INFORMATION         219
101
102
103 struct cmn_registers {
104         union {
105                 struct {
106                         u8 ral;
107                         u8 rah;
108                         u16 rea2;
109                 };
110                 u32 reax;
111         } u1;
112         union {
113                 struct {
114                         u8 rbl;
115                         u8 rbh;
116                         u8 reb2l;
117                         u8 reb2h;
118                 };
119                 u32 rebx;
120         } u2;
121         union {
122                 struct {
123                         u8 rcl;
124                         u8 rch;
125                         u16 rec2;
126                 };
127                 u32 recx;
128         } u3;
129         union {
130                 struct {
131                         u8 rdl;
132                         u8 rdh;
133                         u16 red2;
134                 };
135                 u32 redx;
136         } u4;
137
138         u32 resi;
139         u32 redi;
140         u16 rds;
141         u16 res;
142         u32 reflags;
143 }  __attribute__((packed));
144
145 static unsigned int hpwdt_nmi_decoding;
146 static unsigned int allow_kdump;
147 static unsigned int priority;           /* hpwdt at end of die_notify list */
148 static unsigned int is_icru;
149 static DEFINE_SPINLOCK(rom_lock);
150 static void *cru_rom_addr;
151 static struct cmn_registers cmn_regs;
152
153 extern asmlinkage void asminline_call(struct cmn_registers *pi86Regs,
154                                                 unsigned long *pRomEntry);
155
156 #ifdef CONFIG_X86_32
157 /* --32 Bit Bios------------------------------------------------------------ */
158
159 #define HPWDT_ARCH      32
160
161 asm(".text                          \n\t"
162     ".align 4                       \n"
163     "asminline_call:                \n\t"
164     "pushl       %ebp               \n\t"
165     "movl        %esp, %ebp         \n\t"
166     "pusha                          \n\t"
167     "pushf                          \n\t"
168     "push        %es                \n\t"
169     "push        %ds                \n\t"
170     "pop         %es                \n\t"
171     "movl        8(%ebp),%eax       \n\t"
172     "movl        4(%eax),%ebx       \n\t"
173     "movl        8(%eax),%ecx       \n\t"
174     "movl        12(%eax),%edx      \n\t"
175     "movl        16(%eax),%esi      \n\t"
176     "movl        20(%eax),%edi      \n\t"
177     "movl        (%eax),%eax        \n\t"
178     "push        %cs                \n\t"
179     "call        *12(%ebp)          \n\t"
180     "pushf                          \n\t"
181     "pushl       %eax               \n\t"
182     "movl        8(%ebp),%eax       \n\t"
183     "movl        %ebx,4(%eax)       \n\t"
184     "movl        %ecx,8(%eax)       \n\t"
185     "movl        %edx,12(%eax)      \n\t"
186     "movl        %esi,16(%eax)      \n\t"
187     "movl        %edi,20(%eax)      \n\t"
188     "movw        %ds,24(%eax)       \n\t"
189     "movw        %es,26(%eax)       \n\t"
190     "popl        %ebx               \n\t"
191     "movl        %ebx,(%eax)        \n\t"
192     "popl        %ebx               \n\t"
193     "movl        %ebx,28(%eax)      \n\t"
194     "pop         %es                \n\t"
195     "popf                           \n\t"
196     "popa                           \n\t"
197     "leave                          \n\t"
198     "ret                            \n\t"
199     ".previous");
200
201
202 /*
203  *      cru_detect
204  *
205  *      Routine Description:
206  *      This function uses the 32-bit BIOS Service Directory record to
207  *      search for a $CRU record.
208  *
209  *      Return Value:
210  *      0        :  SUCCESS
211  *      <0       :  FAILURE
212  */
213 static int __devinit cru_detect(unsigned long map_entry,
214         unsigned long map_offset)
215 {
216         void *bios32_map;
217         unsigned long *bios32_entrypoint;
218         unsigned long cru_physical_address;
219         unsigned long cru_length;
220         unsigned long physical_bios_base = 0;
221         unsigned long physical_bios_offset = 0;
222         int retval = -ENODEV;
223
224         bios32_map = ioremap(map_entry, (2 * PAGE_SIZE));
225
226         if (bios32_map == NULL)
227                 return -ENODEV;
228
229         bios32_entrypoint = bios32_map + map_offset;
230
231         cmn_regs.u1.reax = CRU_BIOS_SIGNATURE_VALUE;
232
233         asminline_call(&cmn_regs, bios32_entrypoint);
234
235         if (cmn_regs.u1.ral != 0) {
236                 printk(KERN_WARNING
237                         "hpwdt: Call succeeded but with an error: 0x%x\n",
238                         cmn_regs.u1.ral);
239         } else {
240                 physical_bios_base = cmn_regs.u2.rebx;
241                 physical_bios_offset = cmn_regs.u4.redx;
242                 cru_length = cmn_regs.u3.recx;
243                 cru_physical_address =
244                         physical_bios_base + physical_bios_offset;
245
246                 /* If the values look OK, then map it in. */
247                 if ((physical_bios_base + physical_bios_offset)) {
248                         cru_rom_addr =
249                                 ioremap(cru_physical_address, cru_length);
250                         if (cru_rom_addr)
251                                 retval = 0;
252                 }
253
254                 printk(KERN_DEBUG "hpwdt: CRU Base Address:   0x%lx\n",
255                         physical_bios_base);
256                 printk(KERN_DEBUG "hpwdt: CRU Offset Address: 0x%lx\n",
257                         physical_bios_offset);
258                 printk(KERN_DEBUG "hpwdt: CRU Length:         0x%lx\n",
259                         cru_length);
260                 printk(KERN_DEBUG "hpwdt: CRU Mapped Address: %p\n",
261                         &cru_rom_addr);
262         }
263         iounmap(bios32_map);
264         return retval;
265 }
266
267 /*
268  *      bios_checksum
269  */
270 static int __devinit bios_checksum(const char __iomem *ptr, int len)
271 {
272         char sum = 0;
273         int i;
274
275         /*
276          * calculate checksum of size bytes. This should add up
277          * to zero if we have a valid header.
278          */
279         for (i = 0; i < len; i++)
280                 sum += ptr[i];
281
282         return ((sum == 0) && (len > 0));
283 }
284
285 /*
286  *      bios32_present
287  *
288  *      Routine Description:
289  *      This function finds the 32-bit BIOS Service Directory
290  *
291  *      Return Value:
292  *      0        :  SUCCESS
293  *      <0       :  FAILURE
294  */
295 static int __devinit bios32_present(const char __iomem *p)
296 {
297         struct bios32_service_dir *bios_32_ptr;
298         int length;
299         unsigned long map_entry, map_offset;
300
301         bios_32_ptr = (struct bios32_service_dir *) p;
302
303         /*
304          * Search for signature by checking equal to the swizzled value
305          * instead of calling another routine to perform a strcmp.
306          */
307         if (bios_32_ptr->signature == PCI_BIOS32_SD_VALUE) {
308                 length = bios_32_ptr->length * PCI_BIOS32_PARAGRAPH_LEN;
309                 if (bios_checksum(p, length)) {
310                         /*
311                          * According to the spec, we're looking for the
312                          * first 4KB-aligned address below the entrypoint
313                          * listed in the header. The Service Directory code
314                          * is guaranteed to occupy no more than 2 4KB pages.
315                          */
316                         map_entry = bios_32_ptr->entry_point & ~(PAGE_SIZE - 1);
317                         map_offset = bios_32_ptr->entry_point - map_entry;
318
319                         return cru_detect(map_entry, map_offset);
320                 }
321         }
322         return -ENODEV;
323 }
324
325 static int __devinit detect_cru_service(void)
326 {
327         char __iomem *p, *q;
328         int rc = -1;
329
330         /*
331          * Search from 0x0f0000 through 0x0fffff, inclusive.
332          */
333         p = ioremap(PCI_ROM_BASE1, ROM_SIZE);
334         if (p == NULL)
335                 return -ENOMEM;
336
337         for (q = p; q < p + ROM_SIZE; q += 16) {
338                 rc = bios32_present(q);
339                 if (!rc)
340                         break;
341         }
342         iounmap(p);
343         return rc;
344 }
345 /* ------------------------------------------------------------------------- */
346 #endif /* CONFIG_X86_32 */
347 #ifdef CONFIG_X86_64
348 /* --64 Bit Bios------------------------------------------------------------ */
349
350 #define HPWDT_ARCH      64
351
352 asm(".text                      \n\t"
353     ".align 4                   \n"
354     "asminline_call:            \n\t"
355     "pushq      %rbp            \n\t"
356     "movq       %rsp, %rbp      \n\t"
357     "pushq      %rax            \n\t"
358     "pushq      %rbx            \n\t"
359     "pushq      %rdx            \n\t"
360     "pushq      %r12            \n\t"
361     "pushq      %r9             \n\t"
362     "movq       %rsi, %r12      \n\t"
363     "movq       %rdi, %r9       \n\t"
364     "movl       4(%r9),%ebx     \n\t"
365     "movl       8(%r9),%ecx     \n\t"
366     "movl       12(%r9),%edx    \n\t"
367     "movl       16(%r9),%esi    \n\t"
368     "movl       20(%r9),%edi    \n\t"
369     "movl       (%r9),%eax      \n\t"
370     "call       *%r12           \n\t"
371     "pushfq                     \n\t"
372     "popq        %r12           \n\t"
373     "movl       %eax, (%r9)     \n\t"
374     "movl       %ebx, 4(%r9)    \n\t"
375     "movl       %ecx, 8(%r9)    \n\t"
376     "movl       %edx, 12(%r9)   \n\t"
377     "movl       %esi, 16(%r9)   \n\t"
378     "movl       %edi, 20(%r9)   \n\t"
379     "movq       %r12, %rax      \n\t"
380     "movl       %eax, 28(%r9)   \n\t"
381     "popq       %r9             \n\t"
382     "popq       %r12            \n\t"
383     "popq       %rdx            \n\t"
384     "popq       %rbx            \n\t"
385     "popq       %rax            \n\t"
386     "leave                      \n\t"
387     "ret                        \n\t"
388     ".previous");
389
390 /*
391  *      dmi_find_cru
392  *
393  *      Routine Description:
394  *      This function checks whether or not a SMBIOS/DMI record is
395  *      the 64bit CRU info or not
396  */
397 static void __devinit dmi_find_cru(const struct dmi_header *dm, void *dummy)
398 {
399         struct smbios_cru64_info *smbios_cru64_ptr;
400         unsigned long cru_physical_address;
401
402         if (dm->type == SMBIOS_CRU64_INFORMATION) {
403                 smbios_cru64_ptr = (struct smbios_cru64_info *) dm;
404                 if (smbios_cru64_ptr->signature == CRU_BIOS_SIGNATURE_VALUE) {
405                         cru_physical_address =
406                                 smbios_cru64_ptr->physical_address +
407                                 smbios_cru64_ptr->double_offset;
408                         cru_rom_addr = ioremap(cru_physical_address,
409                                 smbios_cru64_ptr->double_length);
410                         set_memory_x((unsigned long)cru_rom_addr & PAGE_MASK,
411                                 smbios_cru64_ptr->double_length >> PAGE_SHIFT);
412                 }
413         }
414 }
415
416 static int __devinit detect_cru_service(void)
417 {
418         cru_rom_addr = NULL;
419
420         dmi_walk(dmi_find_cru, NULL);
421
422         /* if cru_rom_addr has been set then we found a CRU service */
423         return ((cru_rom_addr != NULL) ? 0 : -ENODEV);
424 }
425 /* ------------------------------------------------------------------------- */
426 #endif /* CONFIG_X86_64 */
427 #endif /* CONFIG_HPWDT_NMI_DECODING */
428
429 /*
430  *      Watchdog operations
431  */
432 static void hpwdt_start(void)
433 {
434         reload = SECS_TO_TICKS(soft_margin);
435         iowrite16(reload, hpwdt_timer_reg);
436         iowrite16(0x85, hpwdt_timer_con);
437 }
438
439 static void hpwdt_stop(void)
440 {
441         unsigned long data;
442
443         data = ioread16(hpwdt_timer_con);
444         data &= 0xFE;
445         iowrite16(data, hpwdt_timer_con);
446 }
447
448 static void hpwdt_ping(void)
449 {
450         iowrite16(reload, hpwdt_timer_reg);
451 }
452
453 static int hpwdt_change_timer(int new_margin)
454 {
455         if (new_margin < 1 || new_margin > HPWDT_MAX_TIMER) {
456                 printk(KERN_WARNING
457                         "hpwdt: New value passed in is invalid: %d seconds.\n",
458                         new_margin);
459                 return -EINVAL;
460         }
461
462         soft_margin = new_margin;
463         printk(KERN_DEBUG
464                 "hpwdt: New timer passed in is %d seconds.\n",
465                 new_margin);
466         reload = SECS_TO_TICKS(soft_margin);
467
468         return 0;
469 }
470
471 static int hpwdt_time_left(void)
472 {
473         return TICKS_TO_SECS(ioread16(hpwdt_timer_reg));
474 }
475
476 #ifdef CONFIG_HPWDT_NMI_DECODING
477 /*
478  *      NMI Handler
479  */
480 static int hpwdt_pretimeout(struct notifier_block *nb, unsigned long ulReason,
481                                 void *data)
482 {
483         unsigned long rom_pl;
484         static int die_nmi_called;
485
486         if (ulReason != DIE_NMIUNKNOWN)
487                 goto out;
488
489         if (!hpwdt_nmi_decoding)
490                 goto out;
491
492         spin_lock_irqsave(&rom_lock, rom_pl);
493         if (!die_nmi_called && !is_icru)
494                 asminline_call(&cmn_regs, cru_rom_addr);
495         die_nmi_called = 1;
496         spin_unlock_irqrestore(&rom_lock, rom_pl);
497         if (!is_icru) {
498                 if (cmn_regs.u1.ral == 0) {
499                         printk(KERN_WARNING "hpwdt: An NMI occurred, "
500                                 "but unable to determine source.\n");
501                 }
502         }
503
504         if (allow_kdump)
505                 hpwdt_stop();
506         panic("An NMI occurred, please see the Integrated "
507                 "Management Log for details.\n");
508
509 out:
510         return NOTIFY_OK;
511 }
512 #endif /* CONFIG_HPWDT_NMI_DECODING */
513
514 /*
515  *      /dev/watchdog handling
516  */
517 static int hpwdt_open(struct inode *inode, struct file *file)
518 {
519         /* /dev/watchdog can only be opened once */
520         if (test_and_set_bit(0, &hpwdt_is_open))
521                 return -EBUSY;
522
523         /* Start the watchdog */
524         hpwdt_start();
525         hpwdt_ping();
526
527         return nonseekable_open(inode, file);
528 }
529
530 static int hpwdt_release(struct inode *inode, struct file *file)
531 {
532         /* Stop the watchdog */
533         if (expect_release == 42) {
534                 hpwdt_stop();
535         } else {
536                 printk(KERN_CRIT
537                         "hpwdt: Unexpected close, not stopping watchdog!\n");
538                 hpwdt_ping();
539         }
540
541         expect_release = 0;
542
543         /* /dev/watchdog is being closed, make sure it can be re-opened */
544         clear_bit(0, &hpwdt_is_open);
545
546         return 0;
547 }
548
549 static ssize_t hpwdt_write(struct file *file, const char __user *data,
550         size_t len, loff_t *ppos)
551 {
552         /* See if we got the magic character 'V' and reload the timer */
553         if (len) {
554                 if (!nowayout) {
555                         size_t i;
556
557                         /* note: just in case someone wrote the magic character
558                          * five months ago... */
559                         expect_release = 0;
560
561                         /* scan to see whether or not we got the magic char. */
562                         for (i = 0; i != len; i++) {
563                                 char c;
564                                 if (get_user(c, data + i))
565                                         return -EFAULT;
566                                 if (c == 'V')
567                                         expect_release = 42;
568                         }
569                 }
570
571                 /* someone wrote to us, we should reload the timer */
572                 hpwdt_ping();
573         }
574
575         return len;
576 }
577
578 static const struct watchdog_info ident = {
579         .options = WDIOF_SETTIMEOUT |
580                    WDIOF_KEEPALIVEPING |
581                    WDIOF_MAGICCLOSE,
582         .identity = "HP iLO2+ HW Watchdog Timer",
583 };
584
585 static long hpwdt_ioctl(struct file *file, unsigned int cmd,
586         unsigned long arg)
587 {
588         void __user *argp = (void __user *)arg;
589         int __user *p = argp;
590         int new_margin;
591         int ret = -ENOTTY;
592
593         switch (cmd) {
594         case WDIOC_GETSUPPORT:
595                 ret = 0;
596                 if (copy_to_user(argp, &ident, sizeof(ident)))
597                         ret = -EFAULT;
598                 break;
599
600         case WDIOC_GETSTATUS:
601         case WDIOC_GETBOOTSTATUS:
602                 ret = put_user(0, p);
603                 break;
604
605         case WDIOC_KEEPALIVE:
606                 hpwdt_ping();
607                 ret = 0;
608                 break;
609
610         case WDIOC_SETTIMEOUT:
611                 ret = get_user(new_margin, p);
612                 if (ret)
613                         break;
614
615                 ret = hpwdt_change_timer(new_margin);
616                 if (ret)
617                         break;
618
619                 hpwdt_ping();
620                 /* Fall */
621         case WDIOC_GETTIMEOUT:
622                 ret = put_user(soft_margin, p);
623                 break;
624
625         case WDIOC_GETTIMELEFT:
626                 ret = put_user(hpwdt_time_left(), p);
627                 break;
628         }
629         return ret;
630 }
631
632 /*
633  *      Kernel interfaces
634  */
635 static const struct file_operations hpwdt_fops = {
636         .owner = THIS_MODULE,
637         .llseek = no_llseek,
638         .write = hpwdt_write,
639         .unlocked_ioctl = hpwdt_ioctl,
640         .open = hpwdt_open,
641         .release = hpwdt_release,
642 };
643
644 static struct miscdevice hpwdt_miscdev = {
645         .minor = WATCHDOG_MINOR,
646         .name = "watchdog",
647         .fops = &hpwdt_fops,
648 };
649
650 #ifdef CONFIG_HPWDT_NMI_DECODING
651 static struct notifier_block die_notifier = {
652         .notifier_call = hpwdt_pretimeout,
653         .priority = 0,
654 };
655 #endif /* CONFIG_HPWDT_NMI_DECODING */
656
657 /*
658  *      Init & Exit
659  */
660
661 #ifdef CONFIG_HPWDT_NMI_DECODING
662 #ifdef CONFIG_X86_LOCAL_APIC
663 static void __devinit hpwdt_check_nmi_decoding(struct pci_dev *dev)
664 {
665         /*
666          * If nmi_watchdog is turned off then we can turn on
667          * our nmi decoding capability.
668          */
669         hpwdt_nmi_decoding = 1;
670 }
671 #else
672 static void __devinit hpwdt_check_nmi_decoding(struct pci_dev *dev)
673 {
674         dev_warn(&dev->dev, "NMI decoding is disabled. "
675                 "Your kernel does not support a NMI Watchdog.\n");
676 }
677 #endif /* CONFIG_X86_LOCAL_APIC */
678
679 /*
680  *      dmi_find_icru
681  *
682  *      Routine Description:
683  *      This function checks whether or not we are on an iCRU-based server.
684  *      This check is independent of architecture and needs to be made for
685  *      any ProLiant system.
686  */
687 static void __devinit dmi_find_icru(const struct dmi_header *dm, void *dummy)
688 {
689         struct smbios_proliant_info *smbios_proliant_ptr;
690
691         if (dm->type == SMBIOS_ICRU_INFORMATION) {
692                 smbios_proliant_ptr = (struct smbios_proliant_info *) dm;
693                 if (smbios_proliant_ptr->misc_features & 0x01)
694                         is_icru = 1;
695         }
696 }
697
698 static int __devinit hpwdt_init_nmi_decoding(struct pci_dev *dev)
699 {
700         int retval;
701
702         /*
703          * On typical CRU-based systems we need to map that service in
704          * the BIOS. For 32 bit Operating Systems we need to go through
705          * the 32 Bit BIOS Service Directory. For 64 bit Operating
706          * Systems we get that service through SMBIOS.
707          *
708          * On systems that support the new iCRU service all we need to
709          * do is call dmi_walk to get the supported flag value and skip
710          * the old cru detect code.
711          */
712         dmi_walk(dmi_find_icru, NULL);
713         if (!is_icru) {
714
715                 /*
716                 * We need to map the ROM to get the CRU service.
717                 * For 32 bit Operating Systems we need to go through the 32 Bit
718                 * BIOS Service Directory
719                 * For 64 bit Operating Systems we get that service through SMBIOS.
720                 */
721                 retval = detect_cru_service();
722                 if (retval < 0) {
723                         dev_warn(&dev->dev,
724                                 "Unable to detect the %d Bit CRU Service.\n",
725                                 HPWDT_ARCH);
726                         return retval;
727                 }
728
729                 /*
730                 * We know this is the only CRU call we need to make so lets keep as
731                 * few instructions as possible once the NMI comes in.
732                 */
733                 cmn_regs.u1.rah = 0x0D;
734                 cmn_regs.u1.ral = 0x02;
735         }
736
737         /*
738          * If the priority is set to 1, then we will be put first on the
739          * die notify list to handle a critical NMI. The default is to
740          * be last so other users of the NMI signal can function.
741          */
742         if (priority)
743                 die_notifier.priority = 0x7FFFFFFF;
744
745         retval = register_die_notifier(&die_notifier);
746         if (retval != 0) {
747                 dev_warn(&dev->dev,
748                         "Unable to register a die notifier (err=%d).\n",
749                         retval);
750                 if (cru_rom_addr)
751                         iounmap(cru_rom_addr);
752         }
753
754         dev_info(&dev->dev,
755                         "HP Watchdog Timer Driver: NMI decoding initialized"
756                         ", allow kernel dump: %s (default = 0/OFF)"
757                         ", priority: %s (default = 0/LAST).\n",
758                         (allow_kdump == 0) ? "OFF" : "ON",
759                         (priority == 0) ? "LAST" : "FIRST");
760         return 0;
761 }
762
763 static void hpwdt_exit_nmi_decoding(void)
764 {
765         unregister_die_notifier(&die_notifier);
766         if (cru_rom_addr)
767                 iounmap(cru_rom_addr);
768 }
769 #else /* !CONFIG_HPWDT_NMI_DECODING */
770 static void __devinit hpwdt_check_nmi_decoding(struct pci_dev *dev)
771 {
772 }
773
774 static int __devinit hpwdt_init_nmi_decoding(struct pci_dev *dev)
775 {
776         return 0;
777 }
778
779 static void hpwdt_exit_nmi_decoding(void)
780 {
781 }
782 #endif /* CONFIG_HPWDT_NMI_DECODING */
783
784 static int __devinit hpwdt_init_one(struct pci_dev *dev,
785                                         const struct pci_device_id *ent)
786 {
787         int retval;
788
789         /*
790          * Check if we can do NMI decoding or not
791          */
792         hpwdt_check_nmi_decoding(dev);
793
794         /*
795          * First let's find out if we are on an iLO2+ server. We will
796          * not run on a legacy ASM box.
797          * So we only support the G5 ProLiant servers and higher.
798          */
799         if (dev->subsystem_vendor != PCI_VENDOR_ID_HP) {
800                 dev_warn(&dev->dev,
801                         "This server does not have an iLO2+ ASIC.\n");
802                 return -ENODEV;
803         }
804
805         if (pci_enable_device(dev)) {
806                 dev_warn(&dev->dev,
807                         "Not possible to enable PCI Device: 0x%x:0x%x.\n",
808                         ent->vendor, ent->device);
809                 return -ENODEV;
810         }
811
812         pci_mem_addr = pci_iomap(dev, 1, 0x80);
813         if (!pci_mem_addr) {
814                 dev_warn(&dev->dev,
815                         "Unable to detect the iLO2+ server memory.\n");
816                 retval = -ENOMEM;
817                 goto error_pci_iomap;
818         }
819         hpwdt_timer_reg = pci_mem_addr + 0x70;
820         hpwdt_timer_con = pci_mem_addr + 0x72;
821
822         /* Make sure that we have a valid soft_margin */
823         if (hpwdt_change_timer(soft_margin))
824                 hpwdt_change_timer(DEFAULT_MARGIN);
825
826         /* Initialize NMI Decoding functionality */
827         retval = hpwdt_init_nmi_decoding(dev);
828         if (retval != 0)
829                 goto error_init_nmi_decoding;
830
831         retval = misc_register(&hpwdt_miscdev);
832         if (retval < 0) {
833                 dev_warn(&dev->dev,
834                         "Unable to register miscdev on minor=%d (err=%d).\n",
835                         WATCHDOG_MINOR, retval);
836                 goto error_misc_register;
837         }
838
839         dev_info(&dev->dev, "HP Watchdog Timer Driver: %s"
840                         ", timer margin: %d seconds (nowayout=%d).\n",
841                         HPWDT_VERSION, soft_margin, nowayout);
842         return 0;
843
844 error_misc_register:
845         hpwdt_exit_nmi_decoding();
846 error_init_nmi_decoding:
847         pci_iounmap(dev, pci_mem_addr);
848 error_pci_iomap:
849         pci_disable_device(dev);
850         return retval;
851 }
852
853 static void __devexit hpwdt_exit(struct pci_dev *dev)
854 {
855         if (!nowayout)
856                 hpwdt_stop();
857
858         misc_deregister(&hpwdt_miscdev);
859         hpwdt_exit_nmi_decoding();
860         pci_iounmap(dev, pci_mem_addr);
861         pci_disable_device(dev);
862 }
863
864 static struct pci_driver hpwdt_driver = {
865         .name = "hpwdt",
866         .id_table = hpwdt_devices,
867         .probe = hpwdt_init_one,
868         .remove = __devexit_p(hpwdt_exit),
869 };
870
871 static void __exit hpwdt_cleanup(void)
872 {
873         pci_unregister_driver(&hpwdt_driver);
874 }
875
876 static int __init hpwdt_init(void)
877 {
878         return pci_register_driver(&hpwdt_driver);
879 }
880
881 MODULE_AUTHOR("Tom Mingarelli");
882 MODULE_DESCRIPTION("hp watchdog driver");
883 MODULE_LICENSE("GPL");
884 MODULE_VERSION(HPWDT_VERSION);
885 MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
886
887 module_param(soft_margin, int, 0);
888 MODULE_PARM_DESC(soft_margin, "Watchdog timeout in seconds");
889
890 module_param(nowayout, int, 0);
891 MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
892                 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
893
894 #ifdef CONFIG_HPWDT_NMI_DECODING
895 module_param(allow_kdump, int, 0);
896 MODULE_PARM_DESC(allow_kdump, "Start a kernel dump after NMI occurs");
897
898 module_param(priority, int, 0);
899 MODULE_PARM_DESC(priority, "The hpwdt driver handles NMIs first or last"
900                 " (default = 0/Last)\n");
901 #endif /* !CONFIG_HPWDT_NMI_DECODING */
902
903 module_init(hpwdt_init);
904 module_exit(hpwdt_cleanup);