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>
43 #include <asm/cacheflush.h>
45 #define PCI_BIOS32_SD_VALUE 0x5F32335F /* "_32_" */
46 #define CRU_BIOS_SIGNATURE_VALUE 0x55524324
47 #define PCI_BIOS32_PARAGRAPH_LEN 16
48 #define PCI_ROM_BASE1 0x000F0000
49 #define ROM_SIZE 0x10000
51 struct bios32_service_dir
{
61 struct smbios_cru64_info
{
70 #define SMBIOS_CRU64_INFORMATION 212
72 struct cmn_registers
{
112 } __attribute__((packed
));
114 #define DEFAULT_MARGIN 30
115 static unsigned int soft_margin
= DEFAULT_MARGIN
; /* in seconds */
116 static unsigned int reload
; /* the computed soft_margin */
117 static int nowayout
= WATCHDOG_NOWAYOUT
;
118 static char expect_release
;
119 static unsigned long hpwdt_is_open
;
120 static unsigned int allow_kdump
;
122 static void __iomem
*pci_mem_addr
; /* the PCI-memory address */
123 static unsigned long __iomem
*hpwdt_timer_reg
;
124 static unsigned long __iomem
*hpwdt_timer_con
;
126 static DEFINE_SPINLOCK(rom_lock
);
128 static void *cru_rom_addr
;
130 static struct cmn_registers cmn_regs
;
132 static struct pci_device_id hpwdt_devices
[] = {
134 .vendor
= PCI_VENDOR_ID_COMPAQ
,
136 .subvendor
= PCI_ANY_ID
,
137 .subdevice
= PCI_ANY_ID
,
139 {0}, /* terminate list */
141 MODULE_DEVICE_TABLE(pci
, hpwdt_devices
);
143 extern asmlinkage
void asminline_call(struct cmn_registers
*pi86Regs
, unsigned long *pRomEntry
);
145 #ifndef CONFIG_X86_64
146 /* --32 Bit Bios------------------------------------------------------------ */
148 #define HPWDT_ARCH 32
152 "asminline_call: \n\t"
154 "movl %esp, %ebp \n\t"
160 "movl 8(%ebp),%eax \n\t"
161 "movl 4(%eax),%ebx \n\t"
162 "movl 8(%eax),%ecx \n\t"
163 "movl 12(%eax),%edx \n\t"
164 "movl 16(%eax),%esi \n\t"
165 "movl 20(%eax),%edi \n\t"
166 "movl (%eax),%eax \n\t"
168 "call *12(%ebp) \n\t"
171 "movl 8(%ebp),%eax \n\t"
172 "movl %ebx,4(%eax) \n\t"
173 "movl %ecx,8(%eax) \n\t"
174 "movl %edx,12(%eax) \n\t"
175 "movl %esi,16(%eax) \n\t"
176 "movl %edi,20(%eax) \n\t"
177 "movw %ds,24(%eax) \n\t"
178 "movw %es,26(%eax) \n\t"
180 "movl %ebx,(%eax) \n\t"
182 "movl %ebx,28(%eax) \n\t"
194 * Routine Description:
195 * This function uses the 32-bit BIOS Service Directory record to
196 * search for a $CRU record.
202 static int __devinit
cru_detect(unsigned long map_entry
,
203 unsigned long map_offset
)
206 unsigned long *bios32_entrypoint
;
207 unsigned long cru_physical_address
;
208 unsigned long cru_length
;
209 unsigned long physical_bios_base
= 0;
210 unsigned long physical_bios_offset
= 0;
211 int retval
= -ENODEV
;
213 bios32_map
= ioremap(map_entry
, (2 * PAGE_SIZE
));
215 if (bios32_map
== NULL
)
218 bios32_entrypoint
= bios32_map
+ map_offset
;
220 cmn_regs
.u1
.reax
= CRU_BIOS_SIGNATURE_VALUE
;
222 asminline_call(&cmn_regs
, bios32_entrypoint
);
224 if (cmn_regs
.u1
.ral
!= 0) {
226 "hpwdt: Call succeeded but with an error: 0x%x\n",
229 physical_bios_base
= cmn_regs
.u2
.rebx
;
230 physical_bios_offset
= cmn_regs
.u4
.redx
;
231 cru_length
= cmn_regs
.u3
.recx
;
232 cru_physical_address
=
233 physical_bios_base
+ physical_bios_offset
;
235 /* If the values look OK, then map it in. */
236 if ((physical_bios_base
+ physical_bios_offset
)) {
238 ioremap(cru_physical_address
, 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: 0x%x\n",
250 (unsigned int)&cru_rom_addr
);
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
);
336 /* --64 Bit Bios------------------------------------------------------------ */
338 #define HPWDT_ARCH 64
342 "asminline_call: \n\t"
344 "movq %rsp, %rbp \n\t"
350 "movq %rsi, %r12 \n\t"
351 "movq %rdi, %r9 \n\t"
352 "movl 4(%r9),%ebx \n\t"
353 "movl 8(%r9),%ecx \n\t"
354 "movl 12(%r9),%edx \n\t"
355 "movl 16(%r9),%esi \n\t"
356 "movl 20(%r9),%edi \n\t"
357 "movl (%r9),%eax \n\t"
361 "movl %eax, (%r9) \n\t"
362 "movl %ebx, 4(%r9) \n\t"
363 "movl %ecx, 8(%r9) \n\t"
364 "movl %edx, 12(%r9) \n\t"
365 "movl %esi, 16(%r9) \n\t"
366 "movl %edi, 20(%r9) \n\t"
367 "movq %r12, %rax \n\t"
368 "movl %eax, 28(%r9) \n\t"
381 * Routine Description:
382 * This function checks whether or not a SMBIOS/DMI record is
383 * the 64bit CRU info or not
385 static void __devinit
dmi_find_cru(const struct dmi_header
*dm
)
387 struct smbios_cru64_info
*smbios_cru64_ptr
;
388 unsigned long cru_physical_address
;
390 if (dm
->type
== SMBIOS_CRU64_INFORMATION
) {
391 smbios_cru64_ptr
= (struct smbios_cru64_info
*) dm
;
392 if (smbios_cru64_ptr
->signature
== CRU_BIOS_SIGNATURE_VALUE
) {
393 cru_physical_address
=
394 smbios_cru64_ptr
->physical_address
+
395 smbios_cru64_ptr
->double_offset
;
396 cru_rom_addr
= ioremap(cru_physical_address
,
397 smbios_cru64_ptr
->double_length
);
398 set_memory_x((unsigned long)cru_rom_addr
& PAGE_MASK
,
399 smbios_cru64_ptr
->double_length
>> PAGE_SHIFT
);
404 static int __devinit
detect_cru_service(void)
408 dmi_walk(dmi_find_cru
);
410 /* if cru_rom_addr has been set then we found a CRU service */
411 return ((cru_rom_addr
!= NULL
) ? 0 : -ENODEV
);
414 /* ------------------------------------------------------------------------- */
419 * Watchdog operations
421 static void hpwdt_start(void)
423 reload
= (soft_margin
* 1000) / 128;
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 /* Arbitrary, can't find the card's limits */
445 if (new_margin
< 30 || new_margin
> 600) {
447 "hpwdt: New value passed in is invalid: %d seconds.\n",
452 soft_margin
= new_margin
;
454 "hpwdt: New timer passed in is %d seconds.\n",
456 reload
= (soft_margin
* 1000) / 128;
464 static int hpwdt_pretimeout(struct notifier_block
*nb
, unsigned long ulReason
,
467 unsigned long rom_pl
;
468 static int die_nmi_called
;
470 if (ulReason
!= DIE_NMI
&& ulReason
!= DIE_NMI_IPI
)
473 spin_lock_irqsave(&rom_lock
, rom_pl
);
475 asminline_call(&cmn_regs
, cru_rom_addr
);
477 spin_unlock_irqrestore(&rom_lock
, rom_pl
);
478 if (cmn_regs
.u1
.ral
== 0) {
479 printk(KERN_WARNING
"hpwdt: An NMI occurred, "
480 "but unable to determine source.\n");
484 panic("An NMI occurred, please see the Integrated "
485 "Management Log for details.\n");
492 * /dev/watchdog handling
494 static int hpwdt_open(struct inode
*inode
, struct file
*file
)
496 /* /dev/watchdog can only be opened once */
497 if (test_and_set_bit(0, &hpwdt_is_open
))
500 /* Start the watchdog */
504 return nonseekable_open(inode
, file
);
507 static int hpwdt_release(struct inode
*inode
, struct file
*file
)
509 /* Stop the watchdog */
510 if (expect_release
== 42) {
514 "hpwdt: Unexpected close, not stopping watchdog!\n");
520 /* /dev/watchdog is being closed, make sure it can be re-opened */
521 clear_bit(0, &hpwdt_is_open
);
526 static ssize_t
hpwdt_write(struct file
*file
, const char __user
*data
,
527 size_t len
, loff_t
*ppos
)
529 /* See if we got the magic character 'V' and reload the timer */
534 /* note: just in case someone wrote the magic character
535 * five months ago... */
538 /* scan to see whether or not we got the magic char. */
539 for (i
= 0; i
!= len
; i
++) {
541 if (get_user(c
, data
+ i
))
548 /* someone wrote to us, we should reload the timer */
555 static struct watchdog_info ident
= {
556 .options
= WDIOF_SETTIMEOUT
|
557 WDIOF_KEEPALIVEPING
|
559 .identity
= "HP iLO2 HW Watchdog Timer",
562 static long hpwdt_ioctl(struct file
*file
, unsigned int cmd
,
565 void __user
*argp
= (void __user
*)arg
;
566 int __user
*p
= argp
;
571 case WDIOC_GETSUPPORT
:
573 if (copy_to_user(argp
, &ident
, sizeof(ident
)))
577 case WDIOC_GETSTATUS
:
578 case WDIOC_GETBOOTSTATUS
:
579 ret
= put_user(0, p
);
582 case WDIOC_KEEPALIVE
:
587 case WDIOC_SETTIMEOUT
:
588 ret
= get_user(new_margin
, p
);
592 ret
= hpwdt_change_timer(new_margin
);
598 case WDIOC_GETTIMEOUT
:
599 ret
= put_user(soft_margin
, p
);
608 static struct file_operations hpwdt_fops
= {
609 .owner
= THIS_MODULE
,
611 .write
= hpwdt_write
,
612 .unlocked_ioctl
= hpwdt_ioctl
,
614 .release
= hpwdt_release
,
617 static struct miscdevice hpwdt_miscdev
= {
618 .minor
= WATCHDOG_MINOR
,
623 static struct notifier_block die_notifier
= {
624 .notifier_call
= hpwdt_pretimeout
,
625 .priority
= 0x7FFFFFFF,
632 static int __devinit
hpwdt_init_one(struct pci_dev
*dev
,
633 const struct pci_device_id
*ent
)
638 * First let's find out if we are on an iLO2 server. We will
639 * not run on a legacy ASM box.
640 * So we only support the G5 ProLiant servers and higher.
642 if (dev
->subsystem_vendor
!= PCI_VENDOR_ID_HP
) {
644 "This server does not have an iLO2 ASIC.\n");
648 if (pci_enable_device(dev
)) {
650 "Not possible to enable PCI Device: 0x%x:0x%x.\n",
651 ent
->vendor
, ent
->device
);
655 pci_mem_addr
= pci_iomap(dev
, 1, 0x80);
658 "Unable to detect the iLO2 server memory.\n");
660 goto error_pci_iomap
;
662 hpwdt_timer_reg
= pci_mem_addr
+ 0x70;
663 hpwdt_timer_con
= pci_mem_addr
+ 0x72;
665 /* Make sure that we have a valid soft_margin */
666 if (hpwdt_change_timer(soft_margin
))
667 hpwdt_change_timer(DEFAULT_MARGIN
);
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;
690 retval
= register_die_notifier(&die_notifier
);
693 "Unable to register a die notifier (err=%d).\n",
695 goto error_die_notifier
;
698 retval
= misc_register(&hpwdt_miscdev
);
701 "Unable to register miscdev on minor=%d (err=%d).\n",
702 WATCHDOG_MINOR
, retval
);
703 goto error_misc_register
;
707 "hp Watchdog Timer Driver: 1.00"
708 ", timer margin: %d seconds (nowayout=%d)"
709 ", allow kernel dump: %s (default = 0/OFF).\n",
710 soft_margin
, nowayout
, (allow_kdump
== 0) ? "OFF" : "ON");
715 unregister_die_notifier(&die_notifier
);
718 iounmap(cru_rom_addr
);
720 pci_iounmap(dev
, pci_mem_addr
);
722 pci_disable_device(dev
);
726 static void __devexit
hpwdt_exit(struct pci_dev
*dev
)
731 misc_deregister(&hpwdt_miscdev
);
732 unregister_die_notifier(&die_notifier
);
735 iounmap(cru_rom_addr
);
736 pci_iounmap(dev
, pci_mem_addr
);
737 pci_disable_device(dev
);
740 static struct pci_driver hpwdt_driver
= {
742 .id_table
= hpwdt_devices
,
743 .probe
= hpwdt_init_one
,
744 .remove
= __devexit_p(hpwdt_exit
),
747 static void __exit
hpwdt_cleanup(void)
749 pci_unregister_driver(&hpwdt_driver
);
752 static int __init
hpwdt_init(void)
754 return pci_register_driver(&hpwdt_driver
);
757 MODULE_AUTHOR("Tom Mingarelli");
758 MODULE_DESCRIPTION("hp watchdog driver");
759 MODULE_LICENSE("GPL");
760 MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR
);
762 module_param(soft_margin
, int, 0);
763 MODULE_PARM_DESC(soft_margin
, "Watchdog timeout in seconds");
765 module_param(allow_kdump
, int, 0);
766 MODULE_PARM_DESC(allow_kdump
, "Start a kernel dump after NMI occurs");
768 module_param(nowayout
, int, 0);
769 MODULE_PARM_DESC(nowayout
, "Watchdog cannot be stopped once started (default="
770 __MODULE_STRING(WATCHDOG_NOWAYOUT
) ")");
772 module_init(hpwdt_init
);
773 module_exit(hpwdt_cleanup
);