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>
19 #include <linux/interrupt.h>
21 #include <linux/irq.h>
22 #include <linux/kernel.h>
23 #include <linux/miscdevice.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>
44 #define PCI_BIOS32_SD_VALUE 0x5F32335F /* "_32_" */
45 #define CRU_BIOS_SIGNATURE_VALUE 0x55524324
46 #define PCI_BIOS32_PARAGRAPH_LEN 16
47 #define PCI_ROM_BASE1 0x000F0000
48 #define ROM_SIZE 0x10000
50 struct bios32_service_dir
{
60 struct smbios_cru64_info
{
69 #define SMBIOS_CRU64_INFORMATION 212
71 struct cmn_registers
{
111 } __attribute__((packed
));
113 #define DEFAULT_MARGIN 30
114 static unsigned int soft_margin
= DEFAULT_MARGIN
; /* in seconds */
115 static unsigned int reload
; /* the computed soft_margin */
116 static int nowayout
= WATCHDOG_NOWAYOUT
;
117 static char expect_release
;
118 static unsigned long hpwdt_is_open
;
120 static void __iomem
*pci_mem_addr
; /* the PCI-memory address */
121 static unsigned long __iomem
*hpwdt_timer_reg
;
122 static unsigned long __iomem
*hpwdt_timer_con
;
124 static DEFINE_SPINLOCK(rom_lock
);
126 static void *cru_rom_addr
;
128 static struct cmn_registers cmn_regs
;
130 static struct pci_device_id hpwdt_devices
[] = {
132 .vendor
= PCI_VENDOR_ID_COMPAQ
,
134 .subvendor
= PCI_ANY_ID
,
135 .subdevice
= PCI_ANY_ID
,
137 {0}, /* terminate list */
139 MODULE_DEVICE_TABLE(pci
, hpwdt_devices
);
141 extern asmlinkage
void asminline_call(struct cmn_registers
*pi86Regs
, unsigned long *pRomEntry
);
143 #ifndef CONFIG_X86_64
144 /* --32 Bit Bios------------------------------------------------------------ */
146 #define HPWDT_ARCH 32
150 "asminline_call: \n\t"
152 "movl %esp, %ebp \n\t"
158 "movl 8(%ebp),%eax \n\t"
159 "movl 4(%eax),%ebx \n\t"
160 "movl 8(%eax),%ecx \n\t"
161 "movl 12(%eax),%edx \n\t"
162 "movl 16(%eax),%esi \n\t"
163 "movl 20(%eax),%edi \n\t"
164 "movl (%eax),%eax \n\t"
166 "call *12(%ebp) \n\t"
169 "movl 8(%ebp),%eax \n\t"
170 "movl %ebx,4(%eax) \n\t"
171 "movl %ecx,8(%eax) \n\t"
172 "movl %edx,12(%eax) \n\t"
173 "movl %esi,16(%eax) \n\t"
174 "movl %edi,20(%eax) \n\t"
175 "movw %ds,24(%eax) \n\t"
176 "movw %es,26(%eax) \n\t"
178 "movl %ebx,(%eax) \n\t"
180 "movl %ebx,28(%eax) \n\t"
192 * Routine Description:
193 * This function uses the 32-bit BIOS Service Directory record to
194 * search for a $CRU record.
200 static int __devinit
cru_detect(unsigned long map_entry
,
201 unsigned long map_offset
)
204 unsigned long *bios32_entrypoint
;
205 unsigned long cru_physical_address
;
206 unsigned long cru_length
;
207 unsigned long physical_bios_base
= 0;
208 unsigned long physical_bios_offset
= 0;
209 int retval
= -ENODEV
;
211 bios32_map
= ioremap(map_entry
, (2 * PAGE_SIZE
));
213 if (bios32_map
== NULL
)
216 bios32_entrypoint
= bios32_map
+ map_offset
;
218 cmn_regs
.u1
.reax
= CRU_BIOS_SIGNATURE_VALUE
;
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
);
241 printk(KERN_DEBUG
"hpwdt: CRU Base Address: 0x%lx\n",
243 printk(KERN_DEBUG
"hpwdt: CRU Offset Address: 0x%lx\n",
244 physical_bios_offset
);
245 printk(KERN_DEBUG
"hpwdt: CRU Length: 0x%lx\n",
247 printk(KERN_DEBUG
"hpwdt: CRU Mapped Address: 0x%x\n",
248 (unsigned int)&cru_rom_addr
);
257 static int __devinit
bios_checksum(const char __iomem
*ptr
, int len
)
263 * calculate checksum of size bytes. This should add up
264 * to zero if we have a valid header.
266 for (i
= 0; i
< len
; i
++)
269 return ((sum
== 0) && (len
> 0));
275 * Routine Description:
276 * This function finds the 32-bit BIOS Service Directory
282 static int __devinit
bios32_present(const char __iomem
*p
)
284 struct bios32_service_dir
*bios_32_ptr
;
286 unsigned long map_entry
, map_offset
;
288 bios_32_ptr
= (struct bios32_service_dir
*) p
;
291 * Search for signature by checking equal to the swizzled value
292 * instead of calling another routine to perform a strcmp.
294 if (bios_32_ptr
->signature
== PCI_BIOS32_SD_VALUE
) {
295 length
= bios_32_ptr
->length
* PCI_BIOS32_PARAGRAPH_LEN
;
296 if (bios_checksum(p
, length
)) {
298 * According to the spec, we're looking for the
299 * first 4KB-aligned address below the entrypoint
300 * listed in the header. The Service Directory code
301 * is guaranteed to occupy no more than 2 4KB pages.
303 map_entry
= bios_32_ptr
->entry_point
& ~(PAGE_SIZE
- 1);
304 map_offset
= bios_32_ptr
->entry_point
- map_entry
;
306 return cru_detect(map_entry
, map_offset
);
312 static int __devinit
detect_cru_service(void)
318 * Search from 0x0f0000 through 0x0fffff, inclusive.
320 p
= ioremap(PCI_ROM_BASE1
, ROM_SIZE
);
324 for (q
= p
; q
< p
+ ROM_SIZE
; q
+= 16) {
325 rc
= bios32_present(q
);
334 /* --64 Bit Bios------------------------------------------------------------ */
336 #define HPWDT_ARCH 64
340 "asminline_call: \n\t"
342 "movq %rsp, %rbp \n\t"
348 "movq %rsi, %r12 \n\t"
349 "movq %rdi, %r9 \n\t"
350 "movl 4(%r9),%ebx \n\t"
351 "movl 8(%r9),%ecx \n\t"
352 "movl 12(%r9),%edx \n\t"
353 "movl 16(%r9),%esi \n\t"
354 "movl 20(%r9),%edi \n\t"
355 "movl (%r9),%eax \n\t"
360 "movl %eax, (%r9) \n\t"
361 "movl %ebx, 4(%r9) \n\t"
362 "movl %ecx, 8(%r9) \n\t"
363 "movl %edx, 12(%r9) \n\t"
364 "movl %esi, 16(%r9) \n\t"
365 "movl %edi, 20(%r9) \n\t"
366 "movq %r12, %rax \n\t"
367 "movl %eax, 28(%r9) \n\t"
380 * Routine Description:
381 * This function checks whether or not a SMBIOS/DMI record is
382 * the 64bit CRU info or not
384 static void __devinit
dmi_find_cru(const struct dmi_header
*dm
)
386 struct smbios_cru64_info
*smbios_cru64_ptr
;
387 unsigned long cru_physical_address
;
389 if (dm
->type
== SMBIOS_CRU64_INFORMATION
) {
390 smbios_cru64_ptr
= (struct smbios_cru64_info
*) dm
;
391 if (smbios_cru64_ptr
->signature
== CRU_BIOS_SIGNATURE_VALUE
) {
392 cru_physical_address
=
393 smbios_cru64_ptr
->physical_address
+
394 smbios_cru64_ptr
->double_offset
;
395 cru_rom_addr
= ioremap(cru_physical_address
,
396 smbios_cru64_ptr
->double_length
);
401 static int __devinit
detect_cru_service(void)
405 dmi_walk(dmi_find_cru
);
407 /* if cru_rom_addr has been set then we found a CRU service */
408 return ((cru_rom_addr
!= NULL
) ? 0: -ENODEV
);
411 /* ------------------------------------------------------------------------- */
418 static int hpwdt_pretimeout(struct notifier_block
*nb
, unsigned long ulReason
,
421 unsigned long rom_pl
;
422 static int die_nmi_called
;
424 if (ulReason
!= DIE_NMI
&& ulReason
!= DIE_NMI_IPI
)
427 spin_lock_irqsave(&rom_lock
, rom_pl
);
429 asminline_call(&cmn_regs
, cru_rom_addr
);
431 spin_unlock_irqrestore(&rom_lock
, rom_pl
);
432 if (cmn_regs
.u1
.ral
== 0) {
433 printk(KERN_WARNING
"hpwdt: An NMI occurred, "
434 "but unable to determine source.\n");
436 panic("An NMI occurred, please see the Integrated "
437 "Management Log for details.\n");
444 * Watchdog operations
446 static void hpwdt_start(void)
448 reload
= (soft_margin
* 1000) / 128;
449 iowrite16(reload
, hpwdt_timer_reg
);
450 iowrite16(0x85, hpwdt_timer_con
);
453 static void hpwdt_stop(void)
457 data
= ioread16(hpwdt_timer_con
);
459 iowrite16(data
, hpwdt_timer_con
);
462 static void hpwdt_ping(void)
464 iowrite16(reload
, hpwdt_timer_reg
);
467 static int hpwdt_change_timer(int new_margin
)
469 /* Arbitrary, can't find the card's limits */
470 if (new_margin
< 30 || new_margin
> 600) {
472 "hpwdt: New value passed in is invalid: %d seconds.\n",
477 soft_margin
= new_margin
;
479 "hpwdt: New timer passed in is %d seconds.\n",
481 reload
= (soft_margin
* 1000) / 128;
487 * /dev/watchdog handling
489 static int hpwdt_open(struct inode
*inode
, struct file
*file
)
491 /* /dev/watchdog can only be opened once */
492 if (test_and_set_bit(0, &hpwdt_is_open
))
495 /* Start the watchdog */
499 return nonseekable_open(inode
, file
);
502 static int hpwdt_release(struct inode
*inode
, struct file
*file
)
504 /* Stop the watchdog */
505 if (expect_release
== 42) {
509 "hpwdt: Unexpected close, not stopping watchdog!\n");
515 /* /dev/watchdog is being closed, make sure it can be re-opened */
516 clear_bit(0, &hpwdt_is_open
);
521 static ssize_t
hpwdt_write(struct file
*file
, const char __user
*data
,
522 size_t len
, loff_t
*ppos
)
524 /* See if we got the magic character 'V' and reload the timer */
529 /* note: just in case someone wrote the magic character
530 * five months ago... */
533 /* scan to see whether or not we got the magic char. */
534 for (i
= 0; i
!= len
; i
++) {
536 if (get_user(c
, data
+ i
))
543 /* someone wrote to us, we should reload the timer */
550 static struct watchdog_info ident
= {
551 .options
= WDIOF_SETTIMEOUT
|
552 WDIOF_KEEPALIVEPING
|
554 .identity
= "HP iLO2 HW Watchdog Timer",
557 static long hpwdt_ioctl(struct file
*file
, unsigned int cmd
,
560 void __user
*argp
= (void __user
*)arg
;
561 int __user
*p
= argp
;
566 case WDIOC_GETSUPPORT
:
568 if (copy_to_user(argp
, &ident
, sizeof(ident
)))
572 case WDIOC_GETSTATUS
:
573 case WDIOC_GETBOOTSTATUS
:
574 ret
= put_user(0, p
);
577 case WDIOC_KEEPALIVE
:
582 case WDIOC_SETTIMEOUT
:
583 ret
= get_user(new_margin
, p
);
587 ret
= hpwdt_change_timer(new_margin
);
593 case WDIOC_GETTIMEOUT
:
594 ret
= put_user(soft_margin
, p
);
603 static struct file_operations hpwdt_fops
= {
604 .owner
= THIS_MODULE
,
606 .write
= hpwdt_write
,
607 .unlocked_ioctl
= hpwdt_ioctl
,
609 .release
= hpwdt_release
,
612 static struct miscdevice hpwdt_miscdev
= {
613 .minor
= WATCHDOG_MINOR
,
618 static struct notifier_block die_notifier
= {
619 .notifier_call
= hpwdt_pretimeout
,
620 .priority
= 0x7FFFFFFF,
627 static int __devinit
hpwdt_init_one(struct pci_dev
*dev
,
628 const struct pci_device_id
*ent
)
633 * First let's find out if we are on an iLO2 server. We will
634 * not run on a legacy ASM box.
636 if (dev
->subsystem_vendor
!= PCI_VENDOR_ID_HP
) {
638 "This server does not have an iLO2 ASIC.\n");
642 if (pci_enable_device(dev
)) {
644 "Not possible to enable PCI Device: 0x%x:0x%x.\n",
645 ent
->vendor
, ent
->device
);
649 pci_mem_addr
= pci_iomap(dev
, 1, 0x80);
652 "Unable to detect the iLO2 server memory.\n");
654 goto error_pci_iomap
;
656 hpwdt_timer_reg
= pci_mem_addr
+ 0x70;
657 hpwdt_timer_con
= pci_mem_addr
+ 0x72;
659 /* Make sure that we have a valid soft_margin */
660 if (hpwdt_change_timer(soft_margin
))
661 hpwdt_change_timer(DEFAULT_MARGIN
);
664 * We need to map the ROM to get the CRU service.
665 * For 32 bit Operating Systems we need to go through the 32 Bit
666 * BIOS Service Directory
667 * For 64 bit Operating Systems we get that service through SMBIOS.
669 retval
= detect_cru_service();
672 "Unable to detect the %d Bit CRU Service.\n",
678 * We know this is the only CRU call we need to make so lets keep as
679 * few instructions as possible once the NMI comes in.
681 cmn_regs
.u1
.rah
= 0x0D;
682 cmn_regs
.u1
.ral
= 0x02;
684 retval
= register_die_notifier(&die_notifier
);
687 "Unable to register a die notifier (err=%d).\n",
689 goto error_die_notifier
;
692 retval
= misc_register(&hpwdt_miscdev
);
695 "Unable to register miscdev on minor=%d (err=%d).\n",
696 WATCHDOG_MINOR
, retval
);
697 goto error_misc_register
;
701 "hp Watchdog Timer Driver: 1.00"
702 ", timer margin: %d seconds( nowayout=%d).\n",
703 soft_margin
, nowayout
);
708 unregister_die_notifier(&die_notifier
);
711 iounmap(cru_rom_addr
);
713 pci_iounmap(dev
, pci_mem_addr
);
715 pci_disable_device(dev
);
719 static void __devexit
hpwdt_exit(struct pci_dev
*dev
)
724 misc_deregister(&hpwdt_miscdev
);
725 unregister_die_notifier(&die_notifier
);
728 iounmap(cru_rom_addr
);
729 pci_iounmap(dev
, pci_mem_addr
);
730 pci_disable_device(dev
);
733 static struct pci_driver hpwdt_driver
= {
735 .id_table
= hpwdt_devices
,
736 .probe
= hpwdt_init_one
,
737 .remove
= __devexit_p(hpwdt_exit
),
740 static void __exit
hpwdt_cleanup(void)
742 pci_unregister_driver(&hpwdt_driver
);
745 static int __init
hpwdt_init(void)
747 return pci_register_driver(&hpwdt_driver
);
750 MODULE_AUTHOR("Tom Mingarelli");
751 MODULE_DESCRIPTION("hp watchdog driver");
752 MODULE_LICENSE("GPL");
753 MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR
);
755 module_param(soft_margin
, int, 0);
756 MODULE_PARM_DESC(soft_margin
, "Watchdog timeout in seconds");
758 module_param(nowayout
, int, 0);
759 MODULE_PARM_DESC(nowayout
, "Watchdog cannot be stopped once started (default="
760 __MODULE_STRING(WATCHDOG_NOWAYOUT
) ")");
762 module_init(hpwdt_init
);
763 module_exit(hpwdt_cleanup
);