/* * HP WatchDog Driver * based on * * SoftDog 0.05: A Software Watchdog Device * * (c) Copyright 2007 Hewlett-Packard Development Company, L.P. * Thomas Mingarelli <thomas.mingarelli@hp.com> * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * version 2 as published by the Free Software Foundation * */ #include <linux/device.h> #include <linux/fs.h> #include <linux/init.h> #include <linux/interrupt.h> #include <linux/io.h> #include <linux/irq.h> #include <linux/kernel.h> #include <linux/miscdevice.h> #include <linux/mm.h> #include <linux/module.h> #include <linux/kdebug.h> #include <linux/moduleparam.h> #include <linux/notifier.h> #include <linux/pci.h> #include <linux/pci_ids.h> #include <linux/reboot.h> #include <linux/sched.h> #include <linux/timer.h> #include <linux/types.h> #include <linux/uaccess.h> #include <linux/watchdog.h> #include <linux/dmi.h> #include <linux/efi.h> #include <linux/string.h> #include <linux/bootmem.h> #include <linux/slab.h> #include <asm/dmi.h> #include <asm/desc.h> #include <asm/kdebug.h> #define PCI_BIOS32_SD_VALUE 0x5F32335F /* "_32_" */ #define CRU_BIOS_SIGNATURE_VALUE 0x55524324 #define PCI_BIOS32_PARAGRAPH_LEN 16 #define PCI_ROM_BASE1 0x000F0000 #define ROM_SIZE 0x10000 struct bios32_service_dir { u32 signature; u32 entry_point; u8 revision; u8 length; u8 checksum; u8 reserved[5]; }; /* type 212 */ struct smbios_cru64_info { u8 type; u8 byte_length; u16 handle; u32 signature; u64 physical_address; u32 double_length; u32 double_offset; }; #define SMBIOS_CRU64_INFORMATION 212 struct cmn_registers { union { struct { u8 ral; u8 rah; u16 rea2; }; u32 reax; } u1; union { struct { u8 rbl; u8 rbh; u8 reb2l; u8 reb2h; }; u32 rebx; } u2; union { struct { u8 rcl; u8 rch; u16 rec2; }; u32 recx; } u3; union { struct { u8 rdl; u8 rdh; u16 red2; }; u32 redx; } u4; u32 resi; u32 redi; u16 rds; u16 res; u32 reflags; } __attribute__((packed)); #define DEFAULT_MARGIN 30 static unsigned int soft_margin = DEFAULT_MARGIN; /* in seconds */ static unsigned int reload; /* the computed soft_margin */ static int nowayout = WATCHDOG_NOWAYOUT; static char expect_release; static unsigned long hpwdt_is_open; static void __iomem *pci_mem_addr; /* the PCI-memory address */ static unsigned long __iomem *hpwdt_timer_reg; static unsigned long __iomem *hpwdt_timer_con; static DEFINE_SPINLOCK(rom_lock); static void *cru_rom_addr; static struct cmn_registers cmn_regs; static struct pci_device_id hpwdt_devices[] = { { .vendor = PCI_VENDOR_ID_COMPAQ, .device = 0xB203, .subvendor = PCI_ANY_ID, .subdevice = PCI_ANY_ID, }, {0}, /* terminate list */ }; MODULE_DEVICE_TABLE(pci, hpwdt_devices); #ifndef CONFIG_X86_64 /* --32 Bit Bios------------------------------------------------------------ */ #define HPWDT_ARCH 32 static void asminline_call(struct cmn_registers *pi86Regs, unsigned long *pRomEntry) { asm("pushl %ebp \n\t" "movl %esp, %ebp \n\t" "pusha \n\t" "pushf \n\t" "push %es \n\t" "push %ds \n\t" "pop %es \n\t" "movl 8(%ebp),%eax \n\t" "movl 4(%eax),%ebx \n\t" "movl 8(%eax),%ecx \n\t" "movl 12(%eax),%edx \n\t" "movl 16(%eax),%esi \n\t" "movl 20(%eax),%edi \n\t" "movl (%eax),%eax \n\t" "push %cs \n\t" "call *12(%ebp) \n\t" "pushf \n\t" "pushl %eax \n\t" "movl 8(%ebp),%eax \n\t" "movl %ebx,4(%eax) \n\t" "movl %ecx,8(%eax) \n\t" "movl %edx,12(%eax) \n\t" "movl %esi,16(%eax) \n\t" "movl %edi,20(%eax) \n\t" "movw %ds,24(%eax) \n\t" "movw %es,26(%eax) \n\t" "popl %ebx \n\t" "movl %ebx,(%eax) \n\t" "popl %ebx \n\t" "movl %ebx,28(%eax) \n\t" "pop %es \n\t" "popf \n\t" "popa \n\t" "leave \n\t" "ret"); } /* * cru_detect * * Routine Description: * This function uses the 32-bit BIOS Service Directory record to * search for a $CRU record. * * Return Value: * 0 : SUCCESS * <0 : FAILURE */ static int __devinit cru_detect(unsigned long map_entry, unsigned long map_offset) { void *bios32_map; unsigned long *bios32_entrypoint; unsigned long cru_physical_address; unsigned long cru_length; unsigned long physical_bios_base = 0; unsigned long physical_bios_offset = 0; int retval = -ENODEV; bios32_map = ioremap(map_entry, (2 * PAGE_SIZE)); if (bios32_map == NULL) return -ENODEV; bios32_entrypoint = bios32_map + map_offset; cmn_regs.u1.reax = CRU_BIOS_SIGNATURE_VALUE; asminline_call(&cmn_regs, bios32_entrypoint); if (cmn_regs.u1.ral != 0) { printk(KERN_WARNING "hpwdt: Call succeeded but with an error: 0x%x\n", cmn_regs.u1.ral); } else { physical_bios_base = cmn_regs.u2.rebx; physical_bios_offset = cmn_regs.u4.redx; cru_length = cmn_regs.u3.recx; cru_physical_address = physical_bios_base + physical_bios_offset; /* If the values look OK, then map it in. */ if ((physical_bios_base + physical_bios_offset)) { cru_rom_addr = ioremap(cru_physical_address, cru_length); if (cru_rom_addr) retval = 0; } printk(KERN_DEBUG "hpwdt: CRU Base Address: 0x%lx\n", physical_bios_base); printk(KERN_DEBUG "hpwdt: CRU Offset Address: 0x%lx\n", physical_bios_offset); printk(KERN_DEBUG "hpwdt: CRU Length: 0x%lx\n", cru_length); printk(KERN_DEBUG "hpwdt: CRU Mapped Address: 0x%x\n", (unsigned int)&cru_rom_addr); } iounmap(bios32_map); return retval; } /* * bios_checksum */ static int __devinit bios_checksum(const char __iomem *ptr, int len) { char sum = 0; int i; /* * calculate checksum of size bytes. This should add up * to zero if we have a valid header. */ for (i = 0; i < len; i++) sum += ptr[i]; return ((sum == 0) && (len > 0)); } /* * bios32_present * * Routine Description: * This function finds the 32-bit BIOS Service Directory * * Return Value: * 0 : SUCCESS * <0 : FAILURE */ static int __devinit bios32_present(const char __iomem *p) { struct bios32_service_dir *bios_32_ptr; int length; unsigned long map_entry, map_offset; bios_32_ptr = (struct bios32_service_dir *) p; /* * Search for signature by checking equal to the swizzled value * instead of calling another routine to perform a strcmp. */ if (bios_32_ptr->signature == PCI_BIOS32_SD_VALUE) { length = bios_32_ptr->length * PCI_BIOS32_PARAGRAPH_LEN; if (bios_checksum(p, length)) { /* * According to the spec, we're looking for the * first 4KB-aligned address below the entrypoint * listed in the header. The Service Directory code * is guaranteed to occupy no more than 2 4KB pages. */ map_entry = bios_32_ptr->entry_point & ~(PAGE_SIZE - 1); map_offset = bios_32_ptr->entry_point - map_entry; return cru_detect(map_entry, map_offset); } } return -ENODEV; } static int __devinit detect_cru_service(void) { char __iomem *p, *q; int rc = -1; /* * Search from 0x0f0000 through 0x0fffff, inclusive. */ p = ioremap(PCI_ROM_BASE1, ROM_SIZE); if (p == NULL) return -ENOMEM; for (q = p; q < p + ROM_SIZE; q += 16) { rc = bios32_present(q); if (!rc) break; } iounmap(p); return rc; } #else /* --64 Bit Bios------------------------------------------------------------ */ #define HPWDT_ARCH 64 static void asminline_call(struct cmn_registers *pi86Regs, unsigned long *pRomEntry) { asm("pushq %rbp \n\t" "movq %rsp, %rbp \n\t" "pushq %rax \n\t" "pushq %rbx \n\t" "pushq %rdx \n\t" "pushq %r12 \n\t" "pushq %r9 \n\t" "movq %rsi, %r12 \n\t" "movq %rdi, %r9 \n\t" "movl 4(%r9),%ebx \n\t" "movl 8(%r9),%ecx \n\t" "movl 12(%r9),%edx \n\t" "movl 16(%r9),%esi \n\t" "movl 20(%r9),%edi \n\t" "movl (%r9),%eax \n\t" "call *%r12 \n\t" "pushfq \n\t" "popq %r12 \n\t" "popfq \n\t" "movl %eax, (%r9) \n\t" "movl %ebx, 4(%r9) \n\t" "movl %ecx, 8(%r9) \n\t" "movl %edx, 12(%r9) \n\t" "movl %esi, 16(%r9) \n\t" "movl %edi, 20(%r9) \n\t" "movq %r12, %rax \n\t" "movl %eax, 28(%r9) \n\t" "popq %r9 \n\t" "popq %r12 \n\t" "popq %rdx \n\t" "popq %rbx \n\t" "popq %rax \n\t" "leave \n\t" "ret"); } /* * dmi_find_cru * * Routine Description: * This function checks whether or not a SMBIOS/DMI record is * the 64bit CRU info or not */ static void __devinit dmi_find_cru(const struct dmi_header *dm) { struct smbios_cru64_info *smbios_cru64_ptr; unsigned long cru_physical_address; if (dm->type == SMBIOS_CRU64_INFORMATION) { smbios_cru64_ptr = (struct smbios_cru64_info *) dm; if (smbios_cru64_ptr->signature == CRU_BIOS_SIGNATURE_VALUE) { cru_physical_address = smbios_cru64_ptr->physical_address + smbios_cru64_ptr->double_offset; cru_rom_addr = ioremap(cru_physical_address, smbios_cru64_ptr->double_length); } } } static int __devinit detect_cru_service(void) { cru_rom_addr = NULL; dmi_walk(dmi_find_cru); /* if cru_rom_addr has been set then we found a CRU service */ return ((cru_rom_addr != NULL)? 0: -ENODEV); } /* ------------------------------------------------------------------------- */ #endif /* * NMI Handler */ static int hpwdt_pretimeout(struct notifier_block *nb, unsigned long ulReason, void *data) { static unsigned long rom_pl; static int die_nmi_called; if (ulReason == DIE_NMI || ulReason == DIE_NMI_IPI) { spin_lock_irqsave(&rom_lock, rom_pl); if (!die_nmi_called) asminline_call(&cmn_regs, cru_rom_addr); die_nmi_called = 1; spin_unlock_irqrestore(&rom_lock, rom_pl); if (cmn_regs.u1.ral != 0) { panic("An NMI occurred, please see the Integrated " "Management Log for details.\n"); } } die_nmi_called = 0; return NOTIFY_DONE; } /* * Watchdog operations */ static void hpwdt_start(void) { reload = (soft_margin * 1000) / 128; iowrite16(reload, hpwdt_timer_reg); iowrite16(0x85, hpwdt_timer_con); } static void hpwdt_stop(void) { unsigned long data; data = ioread16(hpwdt_timer_con); data &= 0xFE; iowrite16(data, hpwdt_timer_con); } static void hpwdt_ping(void) { iowrite16(reload, hpwdt_timer_reg); } static int hpwdt_change_timer(int new_margin) { /* Arbitrary, can't find the card's limits */ if (new_margin < 30 || new_margin > 600) { printk(KERN_WARNING "hpwdt: New value passed in is invalid: %d seconds.\n", new_margin); return -EINVAL; } soft_margin = new_margin; printk(KERN_DEBUG "hpwdt: New timer passed in is %d seconds.\n", new_margin); reload = (soft_margin * 1000) / 128; return 0; } /* * /dev/watchdog handling */ static int hpwdt_open(struct inode *inode, struct file *file) { /* /dev/watchdog can only be opened once */ if (test_and_set_bit(0, &hpwdt_is_open)) return -EBUSY; /* Start the watchdog */ hpwdt_start(); hpwdt_ping(); return nonseekable_open(inode, file); } static int hpwdt_release(struct inode *inode, struct file *file) { /* Stop the watchdog */ if (expect_release == 42) { hpwdt_stop(); } else { printk(KERN_CRIT "hpwdt: Unexpected close, not stopping watchdog!\n"); hpwdt_ping(); } expect_release = 0; /* /dev/watchdog is being closed, make sure it can be re-opened */ clear_bit(0, &hpwdt_is_open); return 0; } static ssize_t hpwdt_write(struct file *file, const char __user *data, size_t len, loff_t *ppos) { /* See if we got the magic character 'V' and reload the timer */ if (len) { if (!nowayout) { size_t i; /* note: just in case someone wrote the magic character * five months ago... */ expect_release = 0; /* scan to see whether or not we got the magic char. */ for (i = 0; i != len; i++) { char c; if (get_user(c, data+i)) return -EFAULT; if (c == 'V') expect_release = 42; } } /* someone wrote to us, we should reload the timer */ hpwdt_ping(); } return len; } static struct watchdog_info ident = { .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE, .identity = "HP iLO2 HW Watchdog Timer", }; static long hpwdt_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { void __user *argp = (void __user *)arg; int __user *p = argp; int new_margin; int ret = -ENOTTY; switch (cmd) { case WDIOC_GETSUPPORT: ret = 0; if (copy_to_user(argp, &ident, sizeof(ident))) ret = -EFAULT; break; case WDIOC_GETSTATUS: case WDIOC_GETBOOTSTATUS: ret = put_user(0, p); break; case WDIOC_KEEPALIVE: hpwdt_ping(); ret = 0; break; case WDIOC_SETTIMEOUT: ret = get_user(new_margin, p); if (ret) break; ret = hpwdt_change_timer(new_margin); if (ret) break; hpwdt_ping(); /* Fall */ case WDIOC_GETTIMEOUT: ret = put_user(soft_margin, p); break; } return ret; } /* * Kernel interfaces */ static struct file_operations hpwdt_fops = { .owner = THIS_MODULE, .llseek = no_llseek, .write = hpwdt_write, .unlocked_ioctl = hpwdt_ioctl, .open = hpwdt_open, .release = hpwdt_release, }; static struct miscdevice hpwdt_miscdev = { .minor = WATCHDOG_MINOR, .name = "watchdog", .fops = &hpwdt_fops, }; static struct notifier_block die_notifier = { .notifier_call = hpwdt_pretimeout, .priority = 0x7FFFFFFF, }; /* * Init & Exit */ static int __devinit hpwdt_init_one(struct pci_dev *dev, const struct pci_device_id *ent) { int retval; /* * First let's find out if we are on an iLO2 server. We will * not run on a legacy ASM box. */ if (dev->subsystem_vendor != PCI_VENDOR_ID_HP) { dev_warn(&dev->dev, "This server does not have an iLO2 ASIC.\n"); return -ENODEV; } if (pci_enable_device(dev)) { dev_warn(&dev->dev, "Not possible to enable PCI Device: 0x%x:0x%x.\n", ent->vendor, ent->device); return -ENODEV; } pci_mem_addr = pci_iomap(dev, 1, 0x80); if (!pci_mem_addr) { dev_warn(&dev->dev, "Unable to detect the iLO2 server memory.\n"); retval = -ENOMEM; goto error_pci_iomap; } hpwdt_timer_reg = pci_mem_addr + 0x70; hpwdt_timer_con = pci_mem_addr + 0x72; /* Make sure that we have a valid soft_margin */ if (hpwdt_change_timer(soft_margin)) hpwdt_change_timer(DEFAULT_MARGIN); /* * We need to map the ROM to get the CRU service. * For 32 bit Operating Systems we need to go through the 32 Bit * BIOS Service Directory * For 64 bit Operating Systems we get that service through SMBIOS. */ retval = detect_cru_service(); if (retval < 0) { dev_warn(&dev->dev, "Unable to detect the %d Bit CRU Service.\n", HPWDT_ARCH); goto error_get_cru; } /* * We know this is the only CRU call we need to make so lets keep as * few instructions as possible once the NMI comes in. */ cmn_regs.u1.rah = 0x0D; cmn_regs.u1.ral = 0x02; retval = register_die_notifier(&die_notifier); if (retval != 0) { dev_warn(&dev->dev, "Unable to register a die notifier (err=%d).\n", retval); goto error_die_notifier; } retval = misc_register(&hpwdt_miscdev); if (retval < 0) { dev_warn(&dev->dev, "Unable to register miscdev on minor=%d (err=%d).\n", WATCHDOG_MINOR, retval); goto error_misc_register; } printk(KERN_INFO "hp Watchdog Timer Driver: 1.00" ", timer margin: %d seconds( nowayout=%d).\n", soft_margin, nowayout); return 0; error_misc_register: unregister_die_notifier(&die_notifier); error_die_notifier: if (cru_rom_addr) iounmap(cru_rom_addr); error_get_cru: pci_iounmap(dev, pci_mem_addr); error_pci_iomap: pci_disable_device(dev); return retval; } static void __devexit hpwdt_exit(struct pci_dev *dev) { if (!nowayout) hpwdt_stop(); misc_deregister(&hpwdt_miscdev); unregister_die_notifier(&die_notifier); if (cru_rom_addr) iounmap(cru_rom_addr); pci_iounmap(dev, pci_mem_addr); pci_disable_device(dev); } static struct pci_driver hpwdt_driver = { .name = "hpwdt", .id_table = hpwdt_devices, .probe = hpwdt_init_one, .remove = __devexit_p(hpwdt_exit), }; static void __exit hpwdt_cleanup(void) { pci_unregister_driver(&hpwdt_driver); } static int __init hpwdt_init(void) { return pci_register_driver(&hpwdt_driver); } MODULE_AUTHOR("Tom Mingarelli"); MODULE_DESCRIPTION("hp watchdog driver"); MODULE_LICENSE("GPL"); MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); module_param(soft_margin, int, 0); MODULE_PARM_DESC(soft_margin, "Watchdog timeout in seconds"); module_param(nowayout, int, 0); MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); module_init(hpwdt_init); module_exit(hpwdt_cleanup);