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 */
40 #define HPWDT_VERSION "1.3.0"
41 #define SECS_TO_TICKS(secs) ((secs) * 1000 / 128)
42 #define TICKS_TO_SECS(ticks) ((ticks) * 128 / 1000)
43 #define HPWDT_MAX_TIMER TICKS_TO_SECS(65535)
44 #define DEFAULT_MARGIN 30
46 static unsigned int soft_margin = DEFAULT_MARGIN; /* in seconds */
47 static unsigned int reload; /* the computed soft_margin */
48 static int nowayout = WATCHDOG_NOWAYOUT;
49 static char expect_release;
50 static unsigned long hpwdt_is_open;
52 static void __iomem *pci_mem_addr; /* the PCI-memory address */
53 static unsigned long __iomem *hpwdt_timer_reg;
54 static unsigned long __iomem *hpwdt_timer_con;
56 static DEFINE_PCI_DEVICE_TABLE(hpwdt_devices) = {
57 { PCI_DEVICE(PCI_VENDOR_ID_COMPAQ, 0xB203) }, /* iLO2 */
58 { PCI_DEVICE(PCI_VENDOR_ID_HP, 0x3306) }, /* iLO3 */
59 {0}, /* terminate list */
61 MODULE_DEVICE_TABLE(pci, hpwdt_devices);
63 #ifdef CONFIG_HPWDT_NMI_DECODING
64 #define PCI_BIOS32_SD_VALUE 0x5F32335F /* "_32_" */
65 #define CRU_BIOS_SIGNATURE_VALUE 0x55524324
66 #define PCI_BIOS32_PARAGRAPH_LEN 16
67 #define PCI_ROM_BASE1 0x000F0000
68 #define ROM_SIZE 0x10000
70 struct bios32_service_dir {
80 struct smbios_cru64_info {
89 #define SMBIOS_CRU64_INFORMATION 212
92 struct smbios_proliant_info {
101 #define SMBIOS_ICRU_INFORMATION 219
104 struct cmn_registers {
144 } __attribute__((packed));
146 static unsigned int hpwdt_nmi_decoding;
147 static unsigned int allow_kdump;
148 static unsigned int priority; /* hpwdt at end of die_notify list */
149 static unsigned int is_icru;
150 static DEFINE_SPINLOCK(rom_lock);
151 static void *cru_rom_addr;
152 static struct cmn_registers cmn_regs;
154 extern asmlinkage void asminline_call(struct cmn_registers *pi86Regs,
155 unsigned long *pRomEntry);
158 /* --32 Bit Bios------------------------------------------------------------ */
160 #define HPWDT_ARCH 32
164 "asminline_call: \n\t"
166 "movl %esp, %ebp \n\t"
172 "movl 8(%ebp),%eax \n\t"
173 "movl 4(%eax),%ebx \n\t"
174 "movl 8(%eax),%ecx \n\t"
175 "movl 12(%eax),%edx \n\t"
176 "movl 16(%eax),%esi \n\t"
177 "movl 20(%eax),%edi \n\t"
178 "movl (%eax),%eax \n\t"
180 "call *12(%ebp) \n\t"
183 "movl 8(%ebp),%eax \n\t"
184 "movl %ebx,4(%eax) \n\t"
185 "movl %ecx,8(%eax) \n\t"
186 "movl %edx,12(%eax) \n\t"
187 "movl %esi,16(%eax) \n\t"
188 "movl %edi,20(%eax) \n\t"
189 "movw %ds,24(%eax) \n\t"
190 "movw %es,26(%eax) \n\t"
192 "movl %ebx,(%eax) \n\t"
194 "movl %ebx,28(%eax) \n\t"
206 * Routine Description:
207 * This function uses the 32-bit BIOS Service Directory record to
208 * search for a $CRU record.
214 static int __devinit cru_detect(unsigned long map_entry,
215 unsigned long map_offset)
218 unsigned long *bios32_entrypoint;
219 unsigned long cru_physical_address;
220 unsigned long cru_length;
221 unsigned long physical_bios_base = 0;
222 unsigned long physical_bios_offset = 0;
223 int retval = -ENODEV;
225 bios32_map = ioremap(map_entry, (2 * PAGE_SIZE));
227 if (bios32_map == NULL)
230 bios32_entrypoint = bios32_map + map_offset;
232 cmn_regs.u1.reax = CRU_BIOS_SIGNATURE_VALUE;
234 set_memory_x((unsigned long)bios32_map, 2);
235 asminline_call(&cmn_regs, bios32_entrypoint);
237 if (cmn_regs.u1.ral != 0) {
239 "hpwdt: Call succeeded but with an error: 0x%x\n",
242 physical_bios_base = cmn_regs.u2.rebx;
243 physical_bios_offset = cmn_regs.u4.redx;
244 cru_length = cmn_regs.u3.recx;
245 cru_physical_address =
246 physical_bios_base + physical_bios_offset;
248 /* If the values look OK, then map it in. */
249 if ((physical_bios_base + physical_bios_offset)) {
251 ioremap(cru_physical_address, cru_length);
253 set_memory_x((unsigned long)cru_rom_addr & PAGE_MASK,
254 (cru_length + PAGE_SIZE - 1) >> PAGE_SHIFT);
259 printk(KERN_DEBUG "hpwdt: CRU Base Address: 0x%lx\n",
261 printk(KERN_DEBUG "hpwdt: CRU Offset Address: 0x%lx\n",
262 physical_bios_offset);
263 printk(KERN_DEBUG "hpwdt: CRU Length: 0x%lx\n",
265 printk(KERN_DEBUG "hpwdt: CRU Mapped Address: %p\n",
275 static int __devinit bios_checksum(const char __iomem *ptr, int len)
281 * calculate checksum of size bytes. This should add up
282 * to zero if we have a valid header.
284 for (i = 0; i < len; i++)
287 return ((sum == 0) && (len > 0));
293 * Routine Description:
294 * This function finds the 32-bit BIOS Service Directory
300 static int __devinit bios32_present(const char __iomem *p)
302 struct bios32_service_dir *bios_32_ptr;
304 unsigned long map_entry, map_offset;
306 bios_32_ptr = (struct bios32_service_dir *) p;
309 * Search for signature by checking equal to the swizzled value
310 * instead of calling another routine to perform a strcmp.
312 if (bios_32_ptr->signature == PCI_BIOS32_SD_VALUE) {
313 length = bios_32_ptr->length * PCI_BIOS32_PARAGRAPH_LEN;
314 if (bios_checksum(p, length)) {
316 * According to the spec, we're looking for the
317 * first 4KB-aligned address below the entrypoint
318 * listed in the header. The Service Directory code
319 * is guaranteed to occupy no more than 2 4KB pages.
321 map_entry = bios_32_ptr->entry_point & ~(PAGE_SIZE - 1);
322 map_offset = bios_32_ptr->entry_point - map_entry;
324 return cru_detect(map_entry, map_offset);
330 static int __devinit detect_cru_service(void)
336 * Search from 0x0f0000 through 0x0fffff, inclusive.
338 p = ioremap(PCI_ROM_BASE1, ROM_SIZE);
342 for (q = p; q < p + ROM_SIZE; q += 16) {
343 rc = bios32_present(q);
350 /* ------------------------------------------------------------------------- */
351 #endif /* CONFIG_X86_32 */
353 /* --64 Bit Bios------------------------------------------------------------ */
355 #define HPWDT_ARCH 64
359 "asminline_call: \n\t"
361 "movq %rsp, %rbp \n\t"
367 "movq %rsi, %r12 \n\t"
368 "movq %rdi, %r9 \n\t"
369 "movl 4(%r9),%ebx \n\t"
370 "movl 8(%r9),%ecx \n\t"
371 "movl 12(%r9),%edx \n\t"
372 "movl 16(%r9),%esi \n\t"
373 "movl 20(%r9),%edi \n\t"
374 "movl (%r9),%eax \n\t"
378 "movl %eax, (%r9) \n\t"
379 "movl %ebx, 4(%r9) \n\t"
380 "movl %ecx, 8(%r9) \n\t"
381 "movl %edx, 12(%r9) \n\t"
382 "movl %esi, 16(%r9) \n\t"
383 "movl %edi, 20(%r9) \n\t"
384 "movq %r12, %rax \n\t"
385 "movl %eax, 28(%r9) \n\t"
398 * Routine Description:
399 * This function checks whether or not a SMBIOS/DMI record is
400 * the 64bit CRU info or not
402 static void __devinit dmi_find_cru(const struct dmi_header *dm, void *dummy)
404 struct smbios_cru64_info *smbios_cru64_ptr;
405 unsigned long cru_physical_address;
407 if (dm->type == SMBIOS_CRU64_INFORMATION) {
408 smbios_cru64_ptr = (struct smbios_cru64_info *) dm;
409 if (smbios_cru64_ptr->signature == CRU_BIOS_SIGNATURE_VALUE) {
410 cru_physical_address =
411 smbios_cru64_ptr->physical_address +
412 smbios_cru64_ptr->double_offset;
413 cru_rom_addr = ioremap(cru_physical_address,
414 smbios_cru64_ptr->double_length);
415 set_memory_x((unsigned long)cru_rom_addr & PAGE_MASK,
416 smbios_cru64_ptr->double_length >> PAGE_SHIFT);
421 static int __devinit detect_cru_service(void)
425 dmi_walk(dmi_find_cru, NULL);
427 /* if cru_rom_addr has been set then we found a CRU service */
428 return ((cru_rom_addr != NULL) ? 0 : -ENODEV);
430 /* ------------------------------------------------------------------------- */
431 #endif /* CONFIG_X86_64 */
432 #endif /* CONFIG_HPWDT_NMI_DECODING */
435 * Watchdog operations
437 static void hpwdt_start(void)
439 reload = SECS_TO_TICKS(soft_margin);
440 iowrite16(reload, hpwdt_timer_reg);
441 iowrite16(0x85, hpwdt_timer_con);
444 static void hpwdt_stop(void)
448 data = ioread16(hpwdt_timer_con);
450 iowrite16(data, hpwdt_timer_con);
453 static void hpwdt_ping(void)
455 iowrite16(reload, hpwdt_timer_reg);
458 static int hpwdt_change_timer(int new_margin)
460 if (new_margin < 1 || new_margin > HPWDT_MAX_TIMER) {
462 "hpwdt: New value passed in is invalid: %d seconds.\n",
467 soft_margin = new_margin;
469 "hpwdt: New timer passed in is %d seconds.\n",
471 reload = SECS_TO_TICKS(soft_margin);
476 static int hpwdt_time_left(void)
478 return TICKS_TO_SECS(ioread16(hpwdt_timer_reg));
481 #ifdef CONFIG_HPWDT_NMI_DECODING
485 static int hpwdt_pretimeout(unsigned int ulReason, struct pt_regs *regs)
487 unsigned long rom_pl;
488 static int die_nmi_called;
490 if (!hpwdt_nmi_decoding)
493 spin_lock_irqsave(&rom_lock, rom_pl);
494 if (!die_nmi_called && !is_icru)
495 asminline_call(&cmn_regs, cru_rom_addr);
497 spin_unlock_irqrestore(&rom_lock, rom_pl);
503 if (cmn_regs.u1.ral == 0) {
504 panic("An NMI occurred, "
505 "but unable to determine source.\n");
508 panic("An NMI occurred, please see the Integrated "
509 "Management Log for details.\n");
514 #endif /* CONFIG_HPWDT_NMI_DECODING */
517 * /dev/watchdog handling
519 static int hpwdt_open(struct inode *inode, struct file *file)
521 /* /dev/watchdog can only be opened once */
522 if (test_and_set_bit(0, &hpwdt_is_open))
525 /* Start the watchdog */
529 return nonseekable_open(inode, file);
532 static int hpwdt_release(struct inode *inode, struct file *file)
534 /* Stop the watchdog */
535 if (expect_release == 42) {
539 "hpwdt: Unexpected close, not stopping watchdog!\n");
545 /* /dev/watchdog is being closed, make sure it can be re-opened */
546 clear_bit(0, &hpwdt_is_open);
551 static ssize_t hpwdt_write(struct file *file, const char __user *data,
552 size_t len, loff_t *ppos)
554 /* See if we got the magic character 'V' and reload the timer */
559 /* note: just in case someone wrote the magic character
560 * five months ago... */
563 /* scan to see whether or not we got the magic char. */
564 for (i = 0; i != len; i++) {
566 if (get_user(c, data + i))
573 /* someone wrote to us, we should reload the timer */
580 static const struct watchdog_info ident = {
581 .options = WDIOF_SETTIMEOUT |
582 WDIOF_KEEPALIVEPING |
584 .identity = "HP iLO2+ HW Watchdog Timer",
587 static long hpwdt_ioctl(struct file *file, unsigned int cmd,
590 void __user *argp = (void __user *)arg;
591 int __user *p = argp;
596 case WDIOC_GETSUPPORT:
598 if (copy_to_user(argp, &ident, sizeof(ident)))
602 case WDIOC_GETSTATUS:
603 case WDIOC_GETBOOTSTATUS:
604 ret = put_user(0, p);
607 case WDIOC_KEEPALIVE:
612 case WDIOC_SETTIMEOUT:
613 ret = get_user(new_margin, p);
617 ret = hpwdt_change_timer(new_margin);
623 case WDIOC_GETTIMEOUT:
624 ret = put_user(soft_margin, p);
627 case WDIOC_GETTIMELEFT:
628 ret = put_user(hpwdt_time_left(), p);
637 static const struct file_operations hpwdt_fops = {
638 .owner = THIS_MODULE,
640 .write = hpwdt_write,
641 .unlocked_ioctl = hpwdt_ioctl,
643 .release = hpwdt_release,
646 static struct miscdevice hpwdt_miscdev = {
647 .minor = WATCHDOG_MINOR,
656 #ifdef CONFIG_HPWDT_NMI_DECODING
657 #ifdef CONFIG_X86_LOCAL_APIC
658 static void __devinit hpwdt_check_nmi_decoding(struct pci_dev *dev)
661 * If nmi_watchdog is turned off then we can turn on
662 * our nmi decoding capability.
664 hpwdt_nmi_decoding = 1;
667 static void __devinit hpwdt_check_nmi_decoding(struct pci_dev *dev)
669 dev_warn(&dev->dev, "NMI decoding is disabled. "
670 "Your kernel does not support a NMI Watchdog.\n");
672 #endif /* CONFIG_X86_LOCAL_APIC */
677 * Routine Description:
678 * This function checks whether or not we are on an iCRU-based server.
679 * This check is independent of architecture and needs to be made for
680 * any ProLiant system.
682 static void __devinit dmi_find_icru(const struct dmi_header *dm, void *dummy)
684 struct smbios_proliant_info *smbios_proliant_ptr;
686 if (dm->type == SMBIOS_ICRU_INFORMATION) {
687 smbios_proliant_ptr = (struct smbios_proliant_info *) dm;
688 if (smbios_proliant_ptr->misc_features & 0x01)
693 static int __devinit hpwdt_init_nmi_decoding(struct pci_dev *dev)
698 * On typical CRU-based systems we need to map that service in
699 * the BIOS. For 32 bit Operating Systems we need to go through
700 * the 32 Bit BIOS Service Directory. For 64 bit Operating
701 * Systems we get that service through SMBIOS.
703 * On systems that support the new iCRU service all we need to
704 * do is call dmi_walk to get the supported flag value and skip
705 * the old cru detect code.
707 dmi_walk(dmi_find_icru, NULL);
711 * We need to map the ROM to get the CRU service.
712 * For 32 bit Operating Systems we need to go through the 32 Bit
713 * BIOS Service Directory
714 * For 64 bit Operating Systems we get that service through SMBIOS.
716 retval = detect_cru_service();
719 "Unable to detect the %d Bit CRU Service.\n",
725 * We know this is the only CRU call we need to make so lets keep as
726 * few instructions as possible once the NMI comes in.
728 cmn_regs.u1.rah = 0x0D;
729 cmn_regs.u1.ral = 0x02;
733 * If the priority is set to 1, then we will be put first on the
734 * die notify list to handle a critical NMI. The default is to
735 * be last so other users of the NMI signal can function.
737 retval = register_nmi_handler(NMI_UNKNOWN, hpwdt_pretimeout,
738 (priority) ? NMI_FLAG_FIRST : 0,
742 "Unable to register a die notifier (err=%d).\n",
745 iounmap(cru_rom_addr);
749 "HP Watchdog Timer Driver: NMI decoding initialized"
750 ", allow kernel dump: %s (default = 0/OFF)"
751 ", priority: %s (default = 0/LAST).\n",
752 (allow_kdump == 0) ? "OFF" : "ON",
753 (priority == 0) ? "LAST" : "FIRST");
757 static void hpwdt_exit_nmi_decoding(void)
759 unregister_nmi_handler(NMI_UNKNOWN, "hpwdt");
761 iounmap(cru_rom_addr);
763 #else /* !CONFIG_HPWDT_NMI_DECODING */
764 static void __devinit hpwdt_check_nmi_decoding(struct pci_dev *dev)
768 static int __devinit hpwdt_init_nmi_decoding(struct pci_dev *dev)
773 static void hpwdt_exit_nmi_decoding(void)
776 #endif /* CONFIG_HPWDT_NMI_DECODING */
778 static int __devinit hpwdt_init_one(struct pci_dev *dev,
779 const struct pci_device_id *ent)
784 * Check if we can do NMI decoding or not
786 hpwdt_check_nmi_decoding(dev);
789 * First let's find out if we are on an iLO2+ server. We will
790 * not run on a legacy ASM box.
791 * So we only support the G5 ProLiant servers and higher.
793 if (dev->subsystem_vendor != PCI_VENDOR_ID_HP) {
795 "This server does not have an iLO2+ ASIC.\n");
799 if (pci_enable_device(dev)) {
801 "Not possible to enable PCI Device: 0x%x:0x%x.\n",
802 ent->vendor, ent->device);
806 pci_mem_addr = pci_iomap(dev, 1, 0x80);
809 "Unable to detect the iLO2+ server memory.\n");
811 goto error_pci_iomap;
813 hpwdt_timer_reg = pci_mem_addr + 0x70;
814 hpwdt_timer_con = pci_mem_addr + 0x72;
816 /* Make sure that timer is disabled until /dev/watchdog is opened */
819 /* Make sure that we have a valid soft_margin */
820 if (hpwdt_change_timer(soft_margin))
821 hpwdt_change_timer(DEFAULT_MARGIN);
823 /* Initialize NMI Decoding functionality */
824 retval = hpwdt_init_nmi_decoding(dev);
826 goto error_init_nmi_decoding;
828 retval = misc_register(&hpwdt_miscdev);
831 "Unable to register miscdev on minor=%d (err=%d).\n",
832 WATCHDOG_MINOR, retval);
833 goto error_misc_register;
836 dev_info(&dev->dev, "HP Watchdog Timer Driver: %s"
837 ", timer margin: %d seconds (nowayout=%d).\n",
838 HPWDT_VERSION, soft_margin, nowayout);
842 hpwdt_exit_nmi_decoding();
843 error_init_nmi_decoding:
844 pci_iounmap(dev, pci_mem_addr);
846 pci_disable_device(dev);
850 static void __devexit hpwdt_exit(struct pci_dev *dev)
855 misc_deregister(&hpwdt_miscdev);
856 hpwdt_exit_nmi_decoding();
857 pci_iounmap(dev, pci_mem_addr);
858 pci_disable_device(dev);
861 static struct pci_driver hpwdt_driver = {
863 .id_table = hpwdt_devices,
864 .probe = hpwdt_init_one,
865 .remove = __devexit_p(hpwdt_exit),
868 static void __exit hpwdt_cleanup(void)
870 pci_unregister_driver(&hpwdt_driver);
873 static int __init hpwdt_init(void)
875 return pci_register_driver(&hpwdt_driver);
878 MODULE_AUTHOR("Tom Mingarelli");
879 MODULE_DESCRIPTION("hp watchdog driver");
880 MODULE_LICENSE("GPL");
881 MODULE_VERSION(HPWDT_VERSION);
882 MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
884 module_param(soft_margin, int, 0);
885 MODULE_PARM_DESC(soft_margin, "Watchdog timeout in seconds");
887 module_param(nowayout, int, 0);
888 MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
889 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
891 #ifdef CONFIG_HPWDT_NMI_DECODING
892 module_param(allow_kdump, int, 0);
893 MODULE_PARM_DESC(allow_kdump, "Start a kernel dump after NMI occurs");
895 module_param(priority, int, 0);
896 MODULE_PARM_DESC(priority, "The hpwdt driver handles NMIs first or last"
897 " (default = 0/Last)\n");
898 #endif /* !CONFIG_HPWDT_NMI_DECODING */
900 module_init(hpwdt_init);
901 module_exit(hpwdt_cleanup);