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 #include <linux/dmi.h>
31 #include <linux/spinlock.h>
32 #include <linux/nmi.h>
33 #include <linux/kdebug.h>
34 #include <linux/notifier.h>
35 #include <asm/cacheflush.h>
37 #define HPWDT_VERSION "1.1.1"
38 #define DEFAULT_MARGIN 30
40 static unsigned int soft_margin
= DEFAULT_MARGIN
; /* in seconds */
41 static unsigned int reload
; /* the computed soft_margin */
42 static int nowayout
= WATCHDOG_NOWAYOUT
;
43 static char expect_release
;
44 static unsigned long hpwdt_is_open
;
46 static void __iomem
*pci_mem_addr
; /* the PCI-memory address */
47 static unsigned long __iomem
*hpwdt_timer_reg
;
48 static unsigned long __iomem
*hpwdt_timer_con
;
50 static struct pci_device_id hpwdt_devices
[] = {
51 { PCI_DEVICE(PCI_VENDOR_ID_COMPAQ
, 0xB203) }, /* iLO2 */
52 { PCI_DEVICE(PCI_VENDOR_ID_HP
, 0x3306) }, /* iLO3 */
53 {0}, /* terminate list */
55 MODULE_DEVICE_TABLE(pci
, hpwdt_devices
);
57 #define PCI_BIOS32_SD_VALUE 0x5F32335F /* "_32_" */
58 #define CRU_BIOS_SIGNATURE_VALUE 0x55524324
59 #define PCI_BIOS32_PARAGRAPH_LEN 16
60 #define PCI_ROM_BASE1 0x000F0000
61 #define ROM_SIZE 0x10000
63 struct bios32_service_dir
{
73 struct smbios_cru64_info
{
82 #define SMBIOS_CRU64_INFORMATION 212
84 struct cmn_registers
{
124 } __attribute__((packed
));
126 static unsigned int hpwdt_nmi_sourcing
;
127 static unsigned int allow_kdump
;
128 static unsigned int priority
; /* hpwdt at end of die_notify list */
129 static DEFINE_SPINLOCK(rom_lock
);
130 static void *cru_rom_addr
;
131 static struct cmn_registers cmn_regs
;
133 extern asmlinkage
void asminline_call(struct cmn_registers
*pi86Regs
,
134 unsigned long *pRomEntry
);
136 #ifndef CONFIG_X86_64
137 /* --32 Bit Bios------------------------------------------------------------ */
139 #define HPWDT_ARCH 32
143 "asminline_call: \n\t"
145 "movl %esp, %ebp \n\t"
151 "movl 8(%ebp),%eax \n\t"
152 "movl 4(%eax),%ebx \n\t"
153 "movl 8(%eax),%ecx \n\t"
154 "movl 12(%eax),%edx \n\t"
155 "movl 16(%eax),%esi \n\t"
156 "movl 20(%eax),%edi \n\t"
157 "movl (%eax),%eax \n\t"
159 "call *12(%ebp) \n\t"
162 "movl 8(%ebp),%eax \n\t"
163 "movl %ebx,4(%eax) \n\t"
164 "movl %ecx,8(%eax) \n\t"
165 "movl %edx,12(%eax) \n\t"
166 "movl %esi,16(%eax) \n\t"
167 "movl %edi,20(%eax) \n\t"
168 "movw %ds,24(%eax) \n\t"
169 "movw %es,26(%eax) \n\t"
171 "movl %ebx,(%eax) \n\t"
173 "movl %ebx,28(%eax) \n\t"
185 * Routine Description:
186 * This function uses the 32-bit BIOS Service Directory record to
187 * search for a $CRU record.
193 static int __devinit
cru_detect(unsigned long map_entry
,
194 unsigned long map_offset
)
197 unsigned long *bios32_entrypoint
;
198 unsigned long cru_physical_address
;
199 unsigned long cru_length
;
200 unsigned long physical_bios_base
= 0;
201 unsigned long physical_bios_offset
= 0;
202 int retval
= -ENODEV
;
204 bios32_map
= ioremap(map_entry
, (2 * PAGE_SIZE
));
206 if (bios32_map
== NULL
)
209 bios32_entrypoint
= bios32_map
+ map_offset
;
211 cmn_regs
.u1
.reax
= CRU_BIOS_SIGNATURE_VALUE
;
213 asminline_call(&cmn_regs
, bios32_entrypoint
);
215 if (cmn_regs
.u1
.ral
!= 0) {
217 "hpwdt: Call succeeded but with an error: 0x%x\n",
220 physical_bios_base
= cmn_regs
.u2
.rebx
;
221 physical_bios_offset
= cmn_regs
.u4
.redx
;
222 cru_length
= cmn_regs
.u3
.recx
;
223 cru_physical_address
=
224 physical_bios_base
+ physical_bios_offset
;
226 /* If the values look OK, then map it in. */
227 if ((physical_bios_base
+ physical_bios_offset
)) {
229 ioremap(cru_physical_address
, cru_length
);
234 printk(KERN_DEBUG
"hpwdt: CRU Base Address: 0x%lx\n",
236 printk(KERN_DEBUG
"hpwdt: CRU Offset Address: 0x%lx\n",
237 physical_bios_offset
);
238 printk(KERN_DEBUG
"hpwdt: CRU Length: 0x%lx\n",
240 printk(KERN_DEBUG
"hpwdt: CRU Mapped Address: %p\n",
250 static int __devinit
bios_checksum(const char __iomem
*ptr
, int len
)
256 * calculate checksum of size bytes. This should add up
257 * to zero if we have a valid header.
259 for (i
= 0; i
< len
; i
++)
262 return ((sum
== 0) && (len
> 0));
268 * Routine Description:
269 * This function finds the 32-bit BIOS Service Directory
275 static int __devinit
bios32_present(const char __iomem
*p
)
277 struct bios32_service_dir
*bios_32_ptr
;
279 unsigned long map_entry
, map_offset
;
281 bios_32_ptr
= (struct bios32_service_dir
*) p
;
284 * Search for signature by checking equal to the swizzled value
285 * instead of calling another routine to perform a strcmp.
287 if (bios_32_ptr
->signature
== PCI_BIOS32_SD_VALUE
) {
288 length
= bios_32_ptr
->length
* PCI_BIOS32_PARAGRAPH_LEN
;
289 if (bios_checksum(p
, length
)) {
291 * According to the spec, we're looking for the
292 * first 4KB-aligned address below the entrypoint
293 * listed in the header. The Service Directory code
294 * is guaranteed to occupy no more than 2 4KB pages.
296 map_entry
= bios_32_ptr
->entry_point
& ~(PAGE_SIZE
- 1);
297 map_offset
= bios_32_ptr
->entry_point
- map_entry
;
299 return cru_detect(map_entry
, map_offset
);
305 static int __devinit
detect_cru_service(void)
311 * Search from 0x0f0000 through 0x0fffff, inclusive.
313 p
= ioremap(PCI_ROM_BASE1
, ROM_SIZE
);
317 for (q
= p
; q
< p
+ ROM_SIZE
; q
+= 16) {
318 rc
= bios32_present(q
);
327 /* --64 Bit Bios------------------------------------------------------------ */
329 #define HPWDT_ARCH 64
333 "asminline_call: \n\t"
335 "movq %rsp, %rbp \n\t"
341 "movq %rsi, %r12 \n\t"
342 "movq %rdi, %r9 \n\t"
343 "movl 4(%r9),%ebx \n\t"
344 "movl 8(%r9),%ecx \n\t"
345 "movl 12(%r9),%edx \n\t"
346 "movl 16(%r9),%esi \n\t"
347 "movl 20(%r9),%edi \n\t"
348 "movl (%r9),%eax \n\t"
352 "movl %eax, (%r9) \n\t"
353 "movl %ebx, 4(%r9) \n\t"
354 "movl %ecx, 8(%r9) \n\t"
355 "movl %edx, 12(%r9) \n\t"
356 "movl %esi, 16(%r9) \n\t"
357 "movl %edi, 20(%r9) \n\t"
358 "movq %r12, %rax \n\t"
359 "movl %eax, 28(%r9) \n\t"
372 * Routine Description:
373 * This function checks whether or not a SMBIOS/DMI record is
374 * the 64bit CRU info or not
376 static void __devinit
dmi_find_cru(const struct dmi_header
*dm
, void *dummy
)
378 struct smbios_cru64_info
*smbios_cru64_ptr
;
379 unsigned long cru_physical_address
;
381 if (dm
->type
== SMBIOS_CRU64_INFORMATION
) {
382 smbios_cru64_ptr
= (struct smbios_cru64_info
*) dm
;
383 if (smbios_cru64_ptr
->signature
== CRU_BIOS_SIGNATURE_VALUE
) {
384 cru_physical_address
=
385 smbios_cru64_ptr
->physical_address
+
386 smbios_cru64_ptr
->double_offset
;
387 cru_rom_addr
= ioremap(cru_physical_address
,
388 smbios_cru64_ptr
->double_length
);
389 set_memory_x((unsigned long)cru_rom_addr
& PAGE_MASK
,
390 smbios_cru64_ptr
->double_length
>> PAGE_SHIFT
);
395 static int __devinit
detect_cru_service(void)
399 dmi_walk(dmi_find_cru
, NULL
);
401 /* if cru_rom_addr has been set then we found a CRU service */
402 return ((cru_rom_addr
!= NULL
) ? 0 : -ENODEV
);
405 /* ------------------------------------------------------------------------- */
410 * Watchdog operations
412 static void hpwdt_start(void)
414 reload
= (soft_margin
* 1000) / 128;
415 iowrite16(reload
, hpwdt_timer_reg
);
416 iowrite16(0x85, hpwdt_timer_con
);
419 static void hpwdt_stop(void)
423 data
= ioread16(hpwdt_timer_con
);
425 iowrite16(data
, hpwdt_timer_con
);
428 static void hpwdt_ping(void)
430 iowrite16(reload
, hpwdt_timer_reg
);
433 static int hpwdt_change_timer(int new_margin
)
435 /* Arbitrary, can't find the card's limits */
436 if (new_margin
< 5 || new_margin
> 600) {
438 "hpwdt: New value passed in is invalid: %d seconds.\n",
443 soft_margin
= new_margin
;
445 "hpwdt: New timer passed in is %d seconds.\n",
447 reload
= (soft_margin
* 1000) / 128;
455 static int hpwdt_pretimeout(struct notifier_block
*nb
, unsigned long ulReason
,
458 unsigned long rom_pl
;
459 static int die_nmi_called
;
461 if (ulReason
!= DIE_NMI
&& ulReason
!= DIE_NMI_IPI
)
464 if (hpwdt_nmi_sourcing
) {
465 spin_lock_irqsave(&rom_lock
, rom_pl
);
467 asminline_call(&cmn_regs
, cru_rom_addr
);
469 spin_unlock_irqrestore(&rom_lock
, rom_pl
);
470 if (cmn_regs
.u1
.ral
== 0) {
471 printk(KERN_WARNING
"hpwdt: An NMI occurred, "
472 "but unable to determine source.\n");
476 panic("An NMI occurred, please see the Integrated "
477 "Management Log for details.\n");
484 * /dev/watchdog handling
486 static int hpwdt_open(struct inode
*inode
, struct file
*file
)
488 /* /dev/watchdog can only be opened once */
489 if (test_and_set_bit(0, &hpwdt_is_open
))
492 /* Start the watchdog */
496 return nonseekable_open(inode
, file
);
499 static int hpwdt_release(struct inode
*inode
, struct file
*file
)
501 /* Stop the watchdog */
502 if (expect_release
== 42) {
506 "hpwdt: Unexpected close, not stopping watchdog!\n");
512 /* /dev/watchdog is being closed, make sure it can be re-opened */
513 clear_bit(0, &hpwdt_is_open
);
518 static ssize_t
hpwdt_write(struct file
*file
, const char __user
*data
,
519 size_t len
, loff_t
*ppos
)
521 /* See if we got the magic character 'V' and reload the timer */
526 /* note: just in case someone wrote the magic character
527 * five months ago... */
530 /* scan to see whether or not we got the magic char. */
531 for (i
= 0; i
!= len
; i
++) {
533 if (get_user(c
, data
+ i
))
540 /* someone wrote to us, we should reload the timer */
547 static const struct watchdog_info ident
= {
548 .options
= WDIOF_SETTIMEOUT
|
549 WDIOF_KEEPALIVEPING
|
551 .identity
= "HP iLO2+ HW Watchdog Timer",
554 static long hpwdt_ioctl(struct file
*file
, unsigned int cmd
,
557 void __user
*argp
= (void __user
*)arg
;
558 int __user
*p
= argp
;
563 case WDIOC_GETSUPPORT
:
565 if (copy_to_user(argp
, &ident
, sizeof(ident
)))
569 case WDIOC_GETSTATUS
:
570 case WDIOC_GETBOOTSTATUS
:
571 ret
= put_user(0, p
);
574 case WDIOC_KEEPALIVE
:
579 case WDIOC_SETTIMEOUT
:
580 ret
= get_user(new_margin
, p
);
584 ret
= hpwdt_change_timer(new_margin
);
590 case WDIOC_GETTIMEOUT
:
591 ret
= put_user(soft_margin
, p
);
600 static const struct file_operations hpwdt_fops
= {
601 .owner
= THIS_MODULE
,
603 .write
= hpwdt_write
,
604 .unlocked_ioctl
= hpwdt_ioctl
,
606 .release
= hpwdt_release
,
609 static struct miscdevice hpwdt_miscdev
= {
610 .minor
= WATCHDOG_MINOR
,
615 static struct notifier_block die_notifier
= {
616 .notifier_call
= hpwdt_pretimeout
,
624 #ifdef ARCH_HAS_NMI_WATCHDOG
625 static void __devinit
hpwdt_check_nmi_sourcing(struct pci_dev
*dev
)
628 * If nmi_watchdog is turned off then we can turn on
629 * our nmi sourcing capability.
631 if (!nmi_watchdog_active())
632 hpwdt_nmi_sourcing
= 1;
634 dev_warn(&dev
->dev
, "NMI sourcing is disabled. To enable this "
635 "functionality you must reboot with nmi_watchdog=0 "
636 "and load the hpwdt driver with priority=1.\n");
639 static void __devinit
hpwdt_check_nmi_sourcing(struct pci_dev
*dev
)
641 dev_warn(&dev
->dev
, "NMI sourcing is disabled. "
642 "Your kernel does not support a NMI Watchdog.\n");
646 static int __devinit
hpwdt_init_one(struct pci_dev
*dev
,
647 const struct pci_device_id
*ent
)
652 * Check if we can do NMI sourcing or not
654 hpwdt_check_nmi_sourcing(dev
);
657 * First let's find out if we are on an iLO2+ server. We will
658 * not run on a legacy ASM box.
659 * So we only support the G5 ProLiant servers and higher.
661 if (dev
->subsystem_vendor
!= PCI_VENDOR_ID_HP
) {
663 "This server does not have an iLO2+ ASIC.\n");
667 if (pci_enable_device(dev
)) {
669 "Not possible to enable PCI Device: 0x%x:0x%x.\n",
670 ent
->vendor
, ent
->device
);
674 pci_mem_addr
= pci_iomap(dev
, 1, 0x80);
677 "Unable to detect the iLO2+ server memory.\n");
679 goto error_pci_iomap
;
681 hpwdt_timer_reg
= pci_mem_addr
+ 0x70;
682 hpwdt_timer_con
= pci_mem_addr
+ 0x72;
684 /* Make sure that we have a valid soft_margin */
685 if (hpwdt_change_timer(soft_margin
))
686 hpwdt_change_timer(DEFAULT_MARGIN
);
689 * We need to map the ROM to get the CRU service.
690 * For 32 bit Operating Systems we need to go through the 32 Bit
691 * BIOS Service Directory
692 * For 64 bit Operating Systems we get that service through SMBIOS.
694 retval
= detect_cru_service();
697 "Unable to detect the %d Bit CRU Service.\n",
703 * We know this is the only CRU call we need to make so lets keep as
704 * few instructions as possible once the NMI comes in.
706 cmn_regs
.u1
.rah
= 0x0D;
707 cmn_regs
.u1
.ral
= 0x02;
710 * If the priority is set to 1, then we will be put first on the
711 * die notify list to handle a critical NMI. The default is to
712 * be last so other users of the NMI signal can function.
715 die_notifier
.priority
= 0x7FFFFFFF;
717 retval
= register_die_notifier(&die_notifier
);
720 "Unable to register a die notifier (err=%d).\n",
722 goto error_die_notifier
;
725 retval
= misc_register(&hpwdt_miscdev
);
728 "Unable to register miscdev on minor=%d (err=%d).\n",
729 WATCHDOG_MINOR
, retval
);
730 goto error_misc_register
;
734 "hp Watchdog Timer Driver: %s"
735 ", timer margin: %d seconds (nowayout=%d)"
736 ", allow kernel dump: %s (default = 0/OFF)"
737 ", priority: %s (default = 0/LAST).\n",
738 HPWDT_VERSION
, soft_margin
, nowayout
,
739 (allow_kdump
== 0) ? "OFF" : "ON",
740 (priority
== 0) ? "LAST" : "FIRST");
745 unregister_die_notifier(&die_notifier
);
748 iounmap(cru_rom_addr
);
750 pci_iounmap(dev
, pci_mem_addr
);
752 pci_disable_device(dev
);
756 static void __devexit
hpwdt_exit(struct pci_dev
*dev
)
761 misc_deregister(&hpwdt_miscdev
);
762 unregister_die_notifier(&die_notifier
);
765 iounmap(cru_rom_addr
);
766 pci_iounmap(dev
, pci_mem_addr
);
767 pci_disable_device(dev
);
770 static struct pci_driver hpwdt_driver
= {
772 .id_table
= hpwdt_devices
,
773 .probe
= hpwdt_init_one
,
774 .remove
= __devexit_p(hpwdt_exit
),
777 static void __exit
hpwdt_cleanup(void)
779 pci_unregister_driver(&hpwdt_driver
);
782 static int __init
hpwdt_init(void)
784 return pci_register_driver(&hpwdt_driver
);
787 MODULE_AUTHOR("Tom Mingarelli");
788 MODULE_DESCRIPTION("hp watchdog driver");
789 MODULE_LICENSE("GPL");
790 MODULE_VERSION(HPWDT_VERSION
);
791 MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR
);
793 module_param(soft_margin
, int, 0);
794 MODULE_PARM_DESC(soft_margin
, "Watchdog timeout in seconds");
796 module_param(nowayout
, int, 0);
797 MODULE_PARM_DESC(nowayout
, "Watchdog cannot be stopped once started (default="
798 __MODULE_STRING(WATCHDOG_NOWAYOUT
) ")");
800 module_param(allow_kdump
, int, 0);
801 MODULE_PARM_DESC(allow_kdump
, "Start a kernel dump after NMI occurs");
803 module_param(priority
, int, 0);
804 MODULE_PARM_DESC(priority
, "The hpwdt driver handles NMIs first or last"
805 " (default = 0/Last)\n");
807 module_init(hpwdt_init
);
808 module_exit(hpwdt_cleanup
);