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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
18 #include <linux/device.h>
20 #include <linux/init.h>
22 #include <linux/bitops.h>
23 #include <linux/kernel.h>
24 #include <linux/miscdevice.h>
25 #include <linux/module.h>
26 #include <linux/moduleparam.h>
27 #include <linux/pci.h>
28 #include <linux/pci_ids.h>
29 #include <linux/types.h>
30 #include <linux/uaccess.h>
31 #include <linux/watchdog.h>
32 #ifdef CONFIG_HPWDT_NMI_DECODING
33 #include <linux/dmi.h>
34 #include <linux/spinlock.h>
35 #include <linux/nmi.h>
36 #include <linux/kdebug.h>
37 #include <linux/notifier.h>
38 #include <asm/cacheflush.h>
39 #endif /* CONFIG_HPWDT_NMI_DECODING */
42 #define HPWDT_VERSION "1.3.0"
43 #define SECS_TO_TICKS(secs) ((secs) * 1000 / 128)
44 #define TICKS_TO_SECS(ticks) ((ticks) * 128 / 1000)
45 #define HPWDT_MAX_TIMER TICKS_TO_SECS(65535)
46 #define DEFAULT_MARGIN 30
48 static unsigned int soft_margin = DEFAULT_MARGIN; /* in seconds */
49 static unsigned int reload; /* the computed soft_margin */
50 static int nowayout = WATCHDOG_NOWAYOUT;
51 static char expect_release;
52 static unsigned long hpwdt_is_open;
54 static void __iomem *pci_mem_addr; /* the PCI-memory address */
55 static unsigned long __iomem *hpwdt_timer_reg;
56 static unsigned long __iomem *hpwdt_timer_con;
58 static DEFINE_PCI_DEVICE_TABLE(hpwdt_devices) = {
59 { PCI_DEVICE(PCI_VENDOR_ID_COMPAQ, 0xB203) }, /* iLO2 */
60 { PCI_DEVICE(PCI_VENDOR_ID_HP, 0x3306) }, /* iLO3 */
61 {0}, /* terminate list */
63 MODULE_DEVICE_TABLE(pci, hpwdt_devices);
65 #ifdef CONFIG_HPWDT_NMI_DECODING
66 #define PCI_BIOS32_SD_VALUE 0x5F32335F /* "_32_" */
67 #define CRU_BIOS_SIGNATURE_VALUE 0x55524324
68 #define PCI_BIOS32_PARAGRAPH_LEN 16
69 #define PCI_ROM_BASE1 0x000F0000
70 #define ROM_SIZE 0x10000
72 struct bios32_service_dir {
82 struct smbios_cru64_info {
91 #define SMBIOS_CRU64_INFORMATION 212
94 struct smbios_proliant_info {
103 #define SMBIOS_ICRU_INFORMATION 219
106 struct cmn_registers {
146 } __attribute__((packed));
148 static unsigned int hpwdt_nmi_decoding;
149 static unsigned int allow_kdump;
150 static unsigned int priority; /* hpwdt at end of die_notify list */
151 static unsigned int is_icru;
152 static DEFINE_SPINLOCK(rom_lock);
153 static void *cru_rom_addr;
154 static struct cmn_registers cmn_regs;
156 extern asmlinkage void asminline_call(struct cmn_registers *pi86Regs,
157 unsigned long *pRomEntry);
160 /* --32 Bit Bios------------------------------------------------------------ */
162 #define HPWDT_ARCH 32
166 "asminline_call: \n\t"
168 "movl %esp, %ebp \n\t"
174 "movl 8(%ebp),%eax \n\t"
175 "movl 4(%eax),%ebx \n\t"
176 "movl 8(%eax),%ecx \n\t"
177 "movl 12(%eax),%edx \n\t"
178 "movl 16(%eax),%esi \n\t"
179 "movl 20(%eax),%edi \n\t"
180 "movl (%eax),%eax \n\t"
182 "call *12(%ebp) \n\t"
185 "movl 8(%ebp),%eax \n\t"
186 "movl %ebx,4(%eax) \n\t"
187 "movl %ecx,8(%eax) \n\t"
188 "movl %edx,12(%eax) \n\t"
189 "movl %esi,16(%eax) \n\t"
190 "movl %edi,20(%eax) \n\t"
191 "movw %ds,24(%eax) \n\t"
192 "movw %es,26(%eax) \n\t"
194 "movl %ebx,(%eax) \n\t"
196 "movl %ebx,28(%eax) \n\t"
208 * Routine Description:
209 * This function uses the 32-bit BIOS Service Directory record to
210 * search for a $CRU record.
216 static int __devinit cru_detect(unsigned long map_entry,
217 unsigned long map_offset)
220 unsigned long *bios32_entrypoint;
221 unsigned long cru_physical_address;
222 unsigned long cru_length;
223 unsigned long physical_bios_base = 0;
224 unsigned long physical_bios_offset = 0;
225 int retval = -ENODEV;
227 bios32_map = ioremap(map_entry, (2 * PAGE_SIZE));
229 if (bios32_map == NULL)
232 bios32_entrypoint = bios32_map + map_offset;
234 cmn_regs.u1.reax = CRU_BIOS_SIGNATURE_VALUE;
236 set_memory_x((unsigned long)bios32_map, 2);
237 asminline_call(&cmn_regs, bios32_entrypoint);
239 if (cmn_regs.u1.ral != 0) {
240 pr_warn("Call succeeded but with an error: 0x%x\n",
243 physical_bios_base = cmn_regs.u2.rebx;
244 physical_bios_offset = cmn_regs.u4.redx;
245 cru_length = cmn_regs.u3.recx;
246 cru_physical_address =
247 physical_bios_base + physical_bios_offset;
249 /* If the values look OK, then map it in. */
250 if ((physical_bios_base + physical_bios_offset)) {
252 ioremap(cru_physical_address, cru_length);
254 set_memory_x((unsigned long)cru_rom_addr & PAGE_MASK,
255 (cru_length + PAGE_SIZE - 1) >> PAGE_SHIFT);
260 pr_debug("CRU Base Address: 0x%lx\n", physical_bios_base);
261 pr_debug("CRU Offset Address: 0x%lx\n", physical_bios_offset);
262 pr_debug("CRU Length: 0x%lx\n", cru_length);
263 pr_debug("CRU Mapped Address: %p\n", &cru_rom_addr);
272 static int __devinit bios_checksum(const char __iomem *ptr, int len)
278 * calculate checksum of size bytes. This should add up
279 * to zero if we have a valid header.
281 for (i = 0; i < len; i++)
284 return ((sum == 0) && (len > 0));
290 * Routine Description:
291 * This function finds the 32-bit BIOS Service Directory
297 static int __devinit bios32_present(const char __iomem *p)
299 struct bios32_service_dir *bios_32_ptr;
301 unsigned long map_entry, map_offset;
303 bios_32_ptr = (struct bios32_service_dir *) p;
306 * Search for signature by checking equal to the swizzled value
307 * instead of calling another routine to perform a strcmp.
309 if (bios_32_ptr->signature == PCI_BIOS32_SD_VALUE) {
310 length = bios_32_ptr->length * PCI_BIOS32_PARAGRAPH_LEN;
311 if (bios_checksum(p, length)) {
313 * According to the spec, we're looking for the
314 * first 4KB-aligned address below the entrypoint
315 * listed in the header. The Service Directory code
316 * is guaranteed to occupy no more than 2 4KB pages.
318 map_entry = bios_32_ptr->entry_point & ~(PAGE_SIZE - 1);
319 map_offset = bios_32_ptr->entry_point - map_entry;
321 return cru_detect(map_entry, map_offset);
327 static int __devinit detect_cru_service(void)
333 * Search from 0x0f0000 through 0x0fffff, inclusive.
335 p = ioremap(PCI_ROM_BASE1, ROM_SIZE);
339 for (q = p; q < p + ROM_SIZE; q += 16) {
340 rc = bios32_present(q);
347 /* ------------------------------------------------------------------------- */
348 #endif /* CONFIG_X86_32 */
350 /* --64 Bit Bios------------------------------------------------------------ */
352 #define HPWDT_ARCH 64
356 "asminline_call: \n\t"
358 "movq %rsp, %rbp \n\t"
364 "movq %rsi, %r12 \n\t"
365 "movq %rdi, %r9 \n\t"
366 "movl 4(%r9),%ebx \n\t"
367 "movl 8(%r9),%ecx \n\t"
368 "movl 12(%r9),%edx \n\t"
369 "movl 16(%r9),%esi \n\t"
370 "movl 20(%r9),%edi \n\t"
371 "movl (%r9),%eax \n\t"
375 "movl %eax, (%r9) \n\t"
376 "movl %ebx, 4(%r9) \n\t"
377 "movl %ecx, 8(%r9) \n\t"
378 "movl %edx, 12(%r9) \n\t"
379 "movl %esi, 16(%r9) \n\t"
380 "movl %edi, 20(%r9) \n\t"
381 "movq %r12, %rax \n\t"
382 "movl %eax, 28(%r9) \n\t"
395 * Routine Description:
396 * This function checks whether or not a SMBIOS/DMI record is
397 * the 64bit CRU info or not
399 static void __devinit dmi_find_cru(const struct dmi_header *dm, void *dummy)
401 struct smbios_cru64_info *smbios_cru64_ptr;
402 unsigned long cru_physical_address;
404 if (dm->type == SMBIOS_CRU64_INFORMATION) {
405 smbios_cru64_ptr = (struct smbios_cru64_info *) dm;
406 if (smbios_cru64_ptr->signature == CRU_BIOS_SIGNATURE_VALUE) {
407 cru_physical_address =
408 smbios_cru64_ptr->physical_address +
409 smbios_cru64_ptr->double_offset;
410 cru_rom_addr = ioremap(cru_physical_address,
411 smbios_cru64_ptr->double_length);
412 set_memory_x((unsigned long)cru_rom_addr & PAGE_MASK,
413 smbios_cru64_ptr->double_length >> PAGE_SHIFT);
418 static int __devinit detect_cru_service(void)
422 dmi_walk(dmi_find_cru, NULL);
424 /* if cru_rom_addr has been set then we found a CRU service */
425 return ((cru_rom_addr != NULL) ? 0 : -ENODEV);
427 /* ------------------------------------------------------------------------- */
428 #endif /* CONFIG_X86_64 */
429 #endif /* CONFIG_HPWDT_NMI_DECODING */
432 * Watchdog operations
434 static void hpwdt_start(void)
436 reload = SECS_TO_TICKS(soft_margin);
437 iowrite16(reload, hpwdt_timer_reg);
438 iowrite16(0x85, hpwdt_timer_con);
441 static void hpwdt_stop(void)
445 data = ioread16(hpwdt_timer_con);
447 iowrite16(data, hpwdt_timer_con);
450 static void hpwdt_ping(void)
452 iowrite16(reload, hpwdt_timer_reg);
455 static int hpwdt_change_timer(int new_margin)
457 if (new_margin < 1 || new_margin > HPWDT_MAX_TIMER) {
458 pr_warn("New value passed in is invalid: %d seconds\n",
463 soft_margin = new_margin;
464 pr_debug("New timer passed in is %d seconds\n", new_margin);
465 reload = SECS_TO_TICKS(soft_margin);
470 static int hpwdt_time_left(void)
472 return TICKS_TO_SECS(ioread16(hpwdt_timer_reg));
475 #ifdef CONFIG_HPWDT_NMI_DECODING
479 static int hpwdt_pretimeout(unsigned int ulReason, struct pt_regs *regs)
481 unsigned long rom_pl;
482 static int die_nmi_called;
484 if (!hpwdt_nmi_decoding)
487 spin_lock_irqsave(&rom_lock, rom_pl);
488 if (!die_nmi_called && !is_icru)
489 asminline_call(&cmn_regs, cru_rom_addr);
491 spin_unlock_irqrestore(&rom_lock, rom_pl);
497 if (cmn_regs.u1.ral == 0) {
498 panic("An NMI occurred, "
499 "but unable to determine source.\n");
502 panic("An NMI occurred, please see the Integrated "
503 "Management Log for details.\n");
508 #endif /* CONFIG_HPWDT_NMI_DECODING */
511 * /dev/watchdog handling
513 static int hpwdt_open(struct inode *inode, struct file *file)
515 /* /dev/watchdog can only be opened once */
516 if (test_and_set_bit(0, &hpwdt_is_open))
519 /* Start the watchdog */
523 return nonseekable_open(inode, file);
526 static int hpwdt_release(struct inode *inode, struct file *file)
528 /* Stop the watchdog */
529 if (expect_release == 42) {
532 pr_crit("Unexpected close, not stopping watchdog!\n");
538 /* /dev/watchdog is being closed, make sure it can be re-opened */
539 clear_bit(0, &hpwdt_is_open);
544 static ssize_t hpwdt_write(struct file *file, const char __user *data,
545 size_t len, loff_t *ppos)
547 /* See if we got the magic character 'V' and reload the timer */
552 /* note: just in case someone wrote the magic character
553 * five months ago... */
556 /* scan to see whether or not we got the magic char. */
557 for (i = 0; i != len; i++) {
559 if (get_user(c, data + i))
566 /* someone wrote to us, we should reload the timer */
573 static const struct watchdog_info ident = {
574 .options = WDIOF_SETTIMEOUT |
575 WDIOF_KEEPALIVEPING |
577 .identity = "HP iLO2+ HW Watchdog Timer",
580 static long hpwdt_ioctl(struct file *file, unsigned int cmd,
583 void __user *argp = (void __user *)arg;
584 int __user *p = argp;
589 case WDIOC_GETSUPPORT:
591 if (copy_to_user(argp, &ident, sizeof(ident)))
595 case WDIOC_GETSTATUS:
596 case WDIOC_GETBOOTSTATUS:
597 ret = put_user(0, p);
600 case WDIOC_KEEPALIVE:
605 case WDIOC_SETTIMEOUT:
606 ret = get_user(new_margin, p);
610 ret = hpwdt_change_timer(new_margin);
616 case WDIOC_GETTIMEOUT:
617 ret = put_user(soft_margin, p);
620 case WDIOC_GETTIMELEFT:
621 ret = put_user(hpwdt_time_left(), p);
630 static const struct file_operations hpwdt_fops = {
631 .owner = THIS_MODULE,
633 .write = hpwdt_write,
634 .unlocked_ioctl = hpwdt_ioctl,
636 .release = hpwdt_release,
639 static struct miscdevice hpwdt_miscdev = {
640 .minor = WATCHDOG_MINOR,
649 #ifdef CONFIG_HPWDT_NMI_DECODING
650 #ifdef CONFIG_X86_LOCAL_APIC
651 static void __devinit hpwdt_check_nmi_decoding(struct pci_dev *dev)
654 * If nmi_watchdog is turned off then we can turn on
655 * our nmi decoding capability.
657 hpwdt_nmi_decoding = 1;
660 static void __devinit hpwdt_check_nmi_decoding(struct pci_dev *dev)
662 dev_warn(&dev->dev, "NMI decoding is disabled. "
663 "Your kernel does not support a NMI Watchdog.\n");
665 #endif /* CONFIG_X86_LOCAL_APIC */
670 * Routine Description:
671 * This function checks whether or not we are on an iCRU-based server.
672 * This check is independent of architecture and needs to be made for
673 * any ProLiant system.
675 static void __devinit dmi_find_icru(const struct dmi_header *dm, void *dummy)
677 struct smbios_proliant_info *smbios_proliant_ptr;
679 if (dm->type == SMBIOS_ICRU_INFORMATION) {
680 smbios_proliant_ptr = (struct smbios_proliant_info *) dm;
681 if (smbios_proliant_ptr->misc_features & 0x01)
686 static int __devinit hpwdt_init_nmi_decoding(struct pci_dev *dev)
691 * On typical CRU-based systems we need to map that service in
692 * the BIOS. For 32 bit Operating Systems we need to go through
693 * the 32 Bit BIOS Service Directory. For 64 bit Operating
694 * Systems we get that service through SMBIOS.
696 * On systems that support the new iCRU service all we need to
697 * do is call dmi_walk to get the supported flag value and skip
698 * the old cru detect code.
700 dmi_walk(dmi_find_icru, NULL);
704 * We need to map the ROM to get the CRU service.
705 * For 32 bit Operating Systems we need to go through the 32 Bit
706 * BIOS Service Directory
707 * For 64 bit Operating Systems we get that service through SMBIOS.
709 retval = detect_cru_service();
712 "Unable to detect the %d Bit CRU Service.\n",
718 * We know this is the only CRU call we need to make so lets keep as
719 * few instructions as possible once the NMI comes in.
721 cmn_regs.u1.rah = 0x0D;
722 cmn_regs.u1.ral = 0x02;
726 * If the priority is set to 1, then we will be put first on the
727 * die notify list to handle a critical NMI. The default is to
728 * be last so other users of the NMI signal can function.
730 retval = register_nmi_handler(NMI_UNKNOWN, hpwdt_pretimeout,
731 (priority) ? NMI_FLAG_FIRST : 0,
735 "Unable to register a die notifier (err=%d).\n",
738 iounmap(cru_rom_addr);
742 "HP Watchdog Timer Driver: NMI decoding initialized"
743 ", allow kernel dump: %s (default = 0/OFF)"
744 ", priority: %s (default = 0/LAST).\n",
745 (allow_kdump == 0) ? "OFF" : "ON",
746 (priority == 0) ? "LAST" : "FIRST");
750 static void hpwdt_exit_nmi_decoding(void)
752 unregister_nmi_handler(NMI_UNKNOWN, "hpwdt");
754 iounmap(cru_rom_addr);
756 #else /* !CONFIG_HPWDT_NMI_DECODING */
757 static void __devinit hpwdt_check_nmi_decoding(struct pci_dev *dev)
761 static int __devinit hpwdt_init_nmi_decoding(struct pci_dev *dev)
766 static void hpwdt_exit_nmi_decoding(void)
769 #endif /* CONFIG_HPWDT_NMI_DECODING */
771 static int __devinit hpwdt_init_one(struct pci_dev *dev,
772 const struct pci_device_id *ent)
777 * Check if we can do NMI decoding or not
779 hpwdt_check_nmi_decoding(dev);
782 * First let's find out if we are on an iLO2+ server. We will
783 * not run on a legacy ASM box.
784 * So we only support the G5 ProLiant servers and higher.
786 if (dev->subsystem_vendor != PCI_VENDOR_ID_HP) {
788 "This server does not have an iLO2+ ASIC.\n");
792 if (pci_enable_device(dev)) {
794 "Not possible to enable PCI Device: 0x%x:0x%x.\n",
795 ent->vendor, ent->device);
799 pci_mem_addr = pci_iomap(dev, 1, 0x80);
802 "Unable to detect the iLO2+ server memory.\n");
804 goto error_pci_iomap;
806 hpwdt_timer_reg = pci_mem_addr + 0x70;
807 hpwdt_timer_con = pci_mem_addr + 0x72;
809 /* Make sure that we have a valid soft_margin */
810 if (hpwdt_change_timer(soft_margin))
811 hpwdt_change_timer(DEFAULT_MARGIN);
813 /* Initialize NMI Decoding functionality */
814 retval = hpwdt_init_nmi_decoding(dev);
816 goto error_init_nmi_decoding;
818 retval = misc_register(&hpwdt_miscdev);
821 "Unable to register miscdev on minor=%d (err=%d).\n",
822 WATCHDOG_MINOR, retval);
823 goto error_misc_register;
826 dev_info(&dev->dev, "HP Watchdog Timer Driver: %s"
827 ", timer margin: %d seconds (nowayout=%d).\n",
828 HPWDT_VERSION, soft_margin, nowayout);
832 hpwdt_exit_nmi_decoding();
833 error_init_nmi_decoding:
834 pci_iounmap(dev, pci_mem_addr);
836 pci_disable_device(dev);
840 static void __devexit hpwdt_exit(struct pci_dev *dev)
845 misc_deregister(&hpwdt_miscdev);
846 hpwdt_exit_nmi_decoding();
847 pci_iounmap(dev, pci_mem_addr);
848 pci_disable_device(dev);
851 static struct pci_driver hpwdt_driver = {
853 .id_table = hpwdt_devices,
854 .probe = hpwdt_init_one,
855 .remove = __devexit_p(hpwdt_exit),
858 static void __exit hpwdt_cleanup(void)
860 pci_unregister_driver(&hpwdt_driver);
863 static int __init hpwdt_init(void)
865 return pci_register_driver(&hpwdt_driver);
868 MODULE_AUTHOR("Tom Mingarelli");
869 MODULE_DESCRIPTION("hp watchdog driver");
870 MODULE_LICENSE("GPL");
871 MODULE_VERSION(HPWDT_VERSION);
872 MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
874 module_param(soft_margin, int, 0);
875 MODULE_PARM_DESC(soft_margin, "Watchdog timeout in seconds");
877 module_param(nowayout, int, 0);
878 MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
879 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
881 #ifdef CONFIG_HPWDT_NMI_DECODING
882 module_param(allow_kdump, int, 0);
883 MODULE_PARM_DESC(allow_kdump, "Start a kernel dump after NMI occurs");
885 module_param(priority, int, 0);
886 MODULE_PARM_DESC(priority, "The hpwdt driver handles NMIs first or last"
887 " (default = 0/Last)\n");
888 #endif /* !CONFIG_HPWDT_NMI_DECODING */
890 module_init(hpwdt_init);
891 module_exit(hpwdt_cleanup);