5 * SoftDog 0.05: A Software Watchdog Device
7 * (c) Copyright 2007 Hewlett-Packard Development Company, L.P.
8 * Thomas Mingarelli <thomas.mingarelli@hp.com>
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
16 #include <linux/device.h>
18 #include <linux/init.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 */
39 #define HPWDT_VERSION "1.2.0"
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
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
;
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
;
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 */
60 MODULE_DEVICE_TABLE(pci
, hpwdt_devices
);
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
69 struct bios32_service_dir
{
79 struct smbios_cru64_info
{
88 #define SMBIOS_CRU64_INFORMATION 212
90 struct cmn_registers
{
130 } __attribute__((packed
));
132 static unsigned int hpwdt_nmi_decoding
;
133 static unsigned int allow_kdump
;
134 static unsigned int priority
; /* hpwdt at end of die_notify list */
135 static DEFINE_SPINLOCK(rom_lock
);
136 static void *cru_rom_addr
;
137 static struct cmn_registers cmn_regs
;
139 extern asmlinkage
void asminline_call(struct cmn_registers
*pi86Regs
,
140 unsigned long *pRomEntry
);
143 /* --32 Bit Bios------------------------------------------------------------ */
145 #define HPWDT_ARCH 32
149 "asminline_call: \n\t"
151 "movl %esp, %ebp \n\t"
157 "movl 8(%ebp),%eax \n\t"
158 "movl 4(%eax),%ebx \n\t"
159 "movl 8(%eax),%ecx \n\t"
160 "movl 12(%eax),%edx \n\t"
161 "movl 16(%eax),%esi \n\t"
162 "movl 20(%eax),%edi \n\t"
163 "movl (%eax),%eax \n\t"
165 "call *12(%ebp) \n\t"
168 "movl 8(%ebp),%eax \n\t"
169 "movl %ebx,4(%eax) \n\t"
170 "movl %ecx,8(%eax) \n\t"
171 "movl %edx,12(%eax) \n\t"
172 "movl %esi,16(%eax) \n\t"
173 "movl %edi,20(%eax) \n\t"
174 "movw %ds,24(%eax) \n\t"
175 "movw %es,26(%eax) \n\t"
177 "movl %ebx,(%eax) \n\t"
179 "movl %ebx,28(%eax) \n\t"
191 * Routine Description:
192 * This function uses the 32-bit BIOS Service Directory record to
193 * search for a $CRU record.
199 static int __devinit
cru_detect(unsigned long map_entry
,
200 unsigned long map_offset
)
203 unsigned long *bios32_entrypoint
;
204 unsigned long cru_physical_address
;
205 unsigned long cru_length
;
206 unsigned long physical_bios_base
= 0;
207 unsigned long physical_bios_offset
= 0;
208 int retval
= -ENODEV
;
210 bios32_map
= ioremap(map_entry
, (2 * PAGE_SIZE
));
212 if (bios32_map
== NULL
)
215 bios32_entrypoint
= bios32_map
+ map_offset
;
217 cmn_regs
.u1
.reax
= CRU_BIOS_SIGNATURE_VALUE
;
219 set_memory_x((unsigned long)bios32_entrypoint
, (2 * PAGE_SIZE
));
220 asminline_call(&cmn_regs
, bios32_entrypoint
);
222 if (cmn_regs
.u1
.ral
!= 0) {
224 "hpwdt: Call succeeded but with an error: 0x%x\n",
227 physical_bios_base
= cmn_regs
.u2
.rebx
;
228 physical_bios_offset
= cmn_regs
.u4
.redx
;
229 cru_length
= cmn_regs
.u3
.recx
;
230 cru_physical_address
=
231 physical_bios_base
+ physical_bios_offset
;
233 /* If the values look OK, then map it in. */
234 if ((physical_bios_base
+ physical_bios_offset
)) {
236 ioremap(cru_physical_address
, cru_length
);
238 set_memory_x((unsigned long)cru_rom_addr
, cru_length
);
243 printk(KERN_DEBUG
"hpwdt: CRU Base Address: 0x%lx\n",
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",
249 printk(KERN_DEBUG
"hpwdt: CRU Mapped Address: %p\n",
259 static int __devinit
bios_checksum(const char __iomem
*ptr
, int len
)
265 * calculate checksum of size bytes. This should add up
266 * to zero if we have a valid header.
268 for (i
= 0; i
< len
; i
++)
271 return ((sum
== 0) && (len
> 0));
277 * Routine Description:
278 * This function finds the 32-bit BIOS Service Directory
284 static int __devinit
bios32_present(const char __iomem
*p
)
286 struct bios32_service_dir
*bios_32_ptr
;
288 unsigned long map_entry
, map_offset
;
290 bios_32_ptr
= (struct bios32_service_dir
*) p
;
293 * Search for signature by checking equal to the swizzled value
294 * instead of calling another routine to perform a strcmp.
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
)) {
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.
305 map_entry
= bios_32_ptr
->entry_point
& ~(PAGE_SIZE
- 1);
306 map_offset
= bios_32_ptr
->entry_point
- map_entry
;
308 return cru_detect(map_entry
, map_offset
);
314 static int __devinit
detect_cru_service(void)
320 * Search from 0x0f0000 through 0x0fffff, inclusive.
322 p
= ioremap(PCI_ROM_BASE1
, ROM_SIZE
);
326 for (q
= p
; q
< p
+ ROM_SIZE
; q
+= 16) {
327 rc
= bios32_present(q
);
334 /* ------------------------------------------------------------------------- */
335 #endif /* CONFIG_X86_32 */
337 /* --64 Bit Bios------------------------------------------------------------ */
339 #define HPWDT_ARCH 64
343 "asminline_call: \n\t"
345 "movq %rsp, %rbp \n\t"
351 "movq %rsi, %r12 \n\t"
352 "movq %rdi, %r9 \n\t"
353 "movl 4(%r9),%ebx \n\t"
354 "movl 8(%r9),%ecx \n\t"
355 "movl 12(%r9),%edx \n\t"
356 "movl 16(%r9),%esi \n\t"
357 "movl 20(%r9),%edi \n\t"
358 "movl (%r9),%eax \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"
382 * Routine Description:
383 * This function checks whether or not a SMBIOS/DMI record is
384 * the 64bit CRU info or not
386 static void __devinit
dmi_find_cru(const struct dmi_header
*dm
, void *dummy
)
388 struct smbios_cru64_info
*smbios_cru64_ptr
;
389 unsigned long cru_physical_address
;
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 set_memory_x((unsigned long)cru_rom_addr
& PAGE_MASK
,
400 smbios_cru64_ptr
->double_length
>> PAGE_SHIFT
);
405 static int __devinit
detect_cru_service(void)
409 dmi_walk(dmi_find_cru
, NULL
);
411 /* if cru_rom_addr has been set then we found a CRU service */
412 return ((cru_rom_addr
!= NULL
) ? 0 : -ENODEV
);
414 /* ------------------------------------------------------------------------- */
415 #endif /* CONFIG_X86_64 */
416 #endif /* CONFIG_HPWDT_NMI_DECODING */
419 * Watchdog operations
421 static void hpwdt_start(void)
423 reload
= SECS_TO_TICKS(soft_margin
);
424 iowrite16(reload
, hpwdt_timer_reg
);
425 iowrite16(0x85, hpwdt_timer_con
);
428 static void hpwdt_stop(void)
432 data
= ioread16(hpwdt_timer_con
);
434 iowrite16(data
, hpwdt_timer_con
);
437 static void hpwdt_ping(void)
439 iowrite16(reload
, hpwdt_timer_reg
);
442 static int hpwdt_change_timer(int new_margin
)
444 if (new_margin
< 1 || new_margin
> HPWDT_MAX_TIMER
) {
446 "hpwdt: New value passed in is invalid: %d seconds.\n",
451 soft_margin
= new_margin
;
453 "hpwdt: New timer passed in is %d seconds.\n",
455 reload
= SECS_TO_TICKS(soft_margin
);
460 static int hpwdt_time_left(void)
462 return TICKS_TO_SECS(ioread16(hpwdt_timer_reg
));
465 #ifdef CONFIG_HPWDT_NMI_DECODING
469 static int hpwdt_pretimeout(struct notifier_block
*nb
, unsigned long ulReason
,
472 unsigned long rom_pl
;
473 static int die_nmi_called
;
475 if (ulReason
!= DIE_NMIUNKNOWN
)
478 if (!hpwdt_nmi_decoding
)
481 spin_lock_irqsave(&rom_lock
, rom_pl
);
483 asminline_call(&cmn_regs
, cru_rom_addr
);
485 spin_unlock_irqrestore(&rom_lock
, rom_pl
);
486 if (cmn_regs
.u1
.ral
== 0) {
487 printk(KERN_WARNING
"hpwdt: An NMI occurred, "
488 "but unable to determine source.\n");
492 panic("An NMI occurred, please see the Integrated "
493 "Management Log for details.\n");
498 #endif /* CONFIG_HPWDT_NMI_DECODING */
501 * /dev/watchdog handling
503 static int hpwdt_open(struct inode
*inode
, struct file
*file
)
505 /* /dev/watchdog can only be opened once */
506 if (test_and_set_bit(0, &hpwdt_is_open
))
509 /* Start the watchdog */
513 return nonseekable_open(inode
, file
);
516 static int hpwdt_release(struct inode
*inode
, struct file
*file
)
518 /* Stop the watchdog */
519 if (expect_release
== 42) {
523 "hpwdt: Unexpected close, not stopping watchdog!\n");
529 /* /dev/watchdog is being closed, make sure it can be re-opened */
530 clear_bit(0, &hpwdt_is_open
);
535 static ssize_t
hpwdt_write(struct file
*file
, const char __user
*data
,
536 size_t len
, loff_t
*ppos
)
538 /* See if we got the magic character 'V' and reload the timer */
543 /* note: just in case someone wrote the magic character
544 * five months ago... */
547 /* scan to see whether or not we got the magic char. */
548 for (i
= 0; i
!= len
; i
++) {
550 if (get_user(c
, data
+ i
))
557 /* someone wrote to us, we should reload the timer */
564 static const struct watchdog_info ident
= {
565 .options
= WDIOF_SETTIMEOUT
|
566 WDIOF_KEEPALIVEPING
|
568 .identity
= "HP iLO2+ HW Watchdog Timer",
571 static long hpwdt_ioctl(struct file
*file
, unsigned int cmd
,
574 void __user
*argp
= (void __user
*)arg
;
575 int __user
*p
= argp
;
580 case WDIOC_GETSUPPORT
:
582 if (copy_to_user(argp
, &ident
, sizeof(ident
)))
586 case WDIOC_GETSTATUS
:
587 case WDIOC_GETBOOTSTATUS
:
588 ret
= put_user(0, p
);
591 case WDIOC_KEEPALIVE
:
596 case WDIOC_SETTIMEOUT
:
597 ret
= get_user(new_margin
, p
);
601 ret
= hpwdt_change_timer(new_margin
);
607 case WDIOC_GETTIMEOUT
:
608 ret
= put_user(soft_margin
, p
);
611 case WDIOC_GETTIMELEFT
:
612 ret
= put_user(hpwdt_time_left(), p
);
621 static const struct file_operations hpwdt_fops
= {
622 .owner
= THIS_MODULE
,
624 .write
= hpwdt_write
,
625 .unlocked_ioctl
= hpwdt_ioctl
,
627 .release
= hpwdt_release
,
630 static struct miscdevice hpwdt_miscdev
= {
631 .minor
= WATCHDOG_MINOR
,
636 #ifdef CONFIG_HPWDT_NMI_DECODING
637 static struct notifier_block die_notifier
= {
638 .notifier_call
= hpwdt_pretimeout
,
641 #endif /* CONFIG_HPWDT_NMI_DECODING */
647 #ifdef CONFIG_HPWDT_NMI_DECODING
648 #ifdef CONFIG_X86_LOCAL_APIC
649 static void __devinit
hpwdt_check_nmi_decoding(struct pci_dev
*dev
)
652 * If nmi_watchdog is turned off then we can turn on
653 * our nmi decoding capability.
655 hpwdt_nmi_decoding
= 1;
658 static void __devinit
hpwdt_check_nmi_decoding(struct pci_dev
*dev
)
660 dev_warn(&dev
->dev
, "NMI decoding is disabled. "
661 "Your kernel does not support a NMI Watchdog.\n");
663 #endif /* CONFIG_X86_LOCAL_APIC */
665 static int __devinit
hpwdt_init_nmi_decoding(struct pci_dev
*dev
)
670 * We need to map the ROM to get the CRU service.
671 * For 32 bit Operating Systems we need to go through the 32 Bit
672 * BIOS Service Directory
673 * For 64 bit Operating Systems we get that service through SMBIOS.
675 retval
= detect_cru_service();
678 "Unable to detect the %d Bit CRU Service.\n",
684 * We know this is the only CRU call we need to make so lets keep as
685 * few instructions as possible once the NMI comes in.
687 cmn_regs
.u1
.rah
= 0x0D;
688 cmn_regs
.u1
.ral
= 0x02;
691 * If the priority is set to 1, then we will be put first on the
692 * die notify list to handle a critical NMI. The default is to
693 * be last so other users of the NMI signal can function.
696 die_notifier
.priority
= 0x7FFFFFFF;
698 retval
= register_die_notifier(&die_notifier
);
701 "Unable to register a die notifier (err=%d).\n",
704 iounmap(cru_rom_addr
);
708 "HP Watchdog Timer Driver: NMI decoding initialized"
709 ", allow kernel dump: %s (default = 0/OFF)"
710 ", priority: %s (default = 0/LAST).\n",
711 (allow_kdump
== 0) ? "OFF" : "ON",
712 (priority
== 0) ? "LAST" : "FIRST");
716 static void hpwdt_exit_nmi_decoding(void)
718 unregister_die_notifier(&die_notifier
);
720 iounmap(cru_rom_addr
);
722 #else /* !CONFIG_HPWDT_NMI_DECODING */
723 static void __devinit
hpwdt_check_nmi_decoding(struct pci_dev
*dev
)
727 static int __devinit
hpwdt_init_nmi_decoding(struct pci_dev
*dev
)
732 static void hpwdt_exit_nmi_decoding(void)
735 #endif /* CONFIG_HPWDT_NMI_DECODING */
737 static int __devinit
hpwdt_init_one(struct pci_dev
*dev
,
738 const struct pci_device_id
*ent
)
743 * Check if we can do NMI decoding or not
745 hpwdt_check_nmi_decoding(dev
);
748 * First let's find out if we are on an iLO2+ server. We will
749 * not run on a legacy ASM box.
750 * So we only support the G5 ProLiant servers and higher.
752 if (dev
->subsystem_vendor
!= PCI_VENDOR_ID_HP
) {
754 "This server does not have an iLO2+ ASIC.\n");
758 if (pci_enable_device(dev
)) {
760 "Not possible to enable PCI Device: 0x%x:0x%x.\n",
761 ent
->vendor
, ent
->device
);
765 pci_mem_addr
= pci_iomap(dev
, 1, 0x80);
768 "Unable to detect the iLO2+ server memory.\n");
770 goto error_pci_iomap
;
772 hpwdt_timer_reg
= pci_mem_addr
+ 0x70;
773 hpwdt_timer_con
= pci_mem_addr
+ 0x72;
775 /* Make sure that we have a valid soft_margin */
776 if (hpwdt_change_timer(soft_margin
))
777 hpwdt_change_timer(DEFAULT_MARGIN
);
779 /* Initialize NMI Decoding functionality */
780 retval
= hpwdt_init_nmi_decoding(dev
);
782 goto error_init_nmi_decoding
;
784 retval
= misc_register(&hpwdt_miscdev
);
787 "Unable to register miscdev on minor=%d (err=%d).\n",
788 WATCHDOG_MINOR
, retval
);
789 goto error_misc_register
;
792 dev_info(&dev
->dev
, "HP Watchdog Timer Driver: %s"
793 ", timer margin: %d seconds (nowayout=%d).\n",
794 HPWDT_VERSION
, soft_margin
, nowayout
);
798 hpwdt_exit_nmi_decoding();
799 error_init_nmi_decoding
:
800 pci_iounmap(dev
, pci_mem_addr
);
802 pci_disable_device(dev
);
806 static void __devexit
hpwdt_exit(struct pci_dev
*dev
)
811 misc_deregister(&hpwdt_miscdev
);
812 hpwdt_exit_nmi_decoding();
813 pci_iounmap(dev
, pci_mem_addr
);
814 pci_disable_device(dev
);
817 static struct pci_driver hpwdt_driver
= {
819 .id_table
= hpwdt_devices
,
820 .probe
= hpwdt_init_one
,
821 .remove
= __devexit_p(hpwdt_exit
),
824 static void __exit
hpwdt_cleanup(void)
826 pci_unregister_driver(&hpwdt_driver
);
829 static int __init
hpwdt_init(void)
831 return pci_register_driver(&hpwdt_driver
);
834 MODULE_AUTHOR("Tom Mingarelli");
835 MODULE_DESCRIPTION("hp watchdog driver");
836 MODULE_LICENSE("GPL");
837 MODULE_VERSION(HPWDT_VERSION
);
838 MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR
);
840 module_param(soft_margin
, int, 0);
841 MODULE_PARM_DESC(soft_margin
, "Watchdog timeout in seconds");
843 module_param(nowayout
, int, 0);
844 MODULE_PARM_DESC(nowayout
, "Watchdog cannot be stopped once started (default="
845 __MODULE_STRING(WATCHDOG_NOWAYOUT
) ")");
847 #ifdef CONFIG_HPWDT_NMI_DECODING
848 module_param(allow_kdump
, int, 0);
849 MODULE_PARM_DESC(allow_kdump
, "Start a kernel dump after NMI occurs");
851 module_param(priority
, int, 0);
852 MODULE_PARM_DESC(priority
, "The hpwdt driver handles NMIs first or last"
853 " (default = 0/Last)\n");
854 #endif /* !CONFIG_HPWDT_NMI_DECODING */
856 module_init(hpwdt_init
);
857 module_exit(hpwdt_cleanup
);