| /* |
| * HPE WatchDog Driver |
| * based on |
| * |
| * SoftDog 0.05: A Software Watchdog Device |
| * |
| * (c) Copyright 2015 Hewlett Packard Enterprise Development LP |
| * Thomas Mingarelli <thomas.mingarelli@hpe.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 |
| * |
| */ |
| |
| #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
| |
| #include <linux/device.h> |
| #include <linux/fs.h> |
| #include <linux/io.h> |
| #include <linux/bitops.h> |
| #include <linux/kernel.h> |
| #include <linux/miscdevice.h> |
| #include <linux/module.h> |
| #include <linux/moduleparam.h> |
| #include <linux/pci.h> |
| #include <linux/pci_ids.h> |
| #include <linux/types.h> |
| #include <linux/uaccess.h> |
| #include <linux/watchdog.h> |
| #include <asm/nmi.h> |
| |
| #define HPWDT_VERSION "1.4.0" |
| #define SECS_TO_TICKS(secs) ((secs) * 1000 / 128) |
| #define TICKS_TO_SECS(ticks) ((ticks) * 128 / 1000) |
| #define HPWDT_MAX_TIMER TICKS_TO_SECS(65535) |
| #define DEFAULT_MARGIN 30 |
| |
| static unsigned int soft_margin = DEFAULT_MARGIN; /* in seconds */ |
| static unsigned int reload; /* the computed soft_margin */ |
| static bool nowayout = WATCHDOG_NOWAYOUT; |
| #ifdef CONFIG_HPWDT_NMI_DECODING |
| static unsigned int allow_kdump = 1; |
| #endif |
| 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_nmistat; |
| static unsigned long __iomem *hpwdt_timer_reg; |
| static unsigned long __iomem *hpwdt_timer_con; |
| |
| static const struct pci_device_id hpwdt_devices[] = { |
| { PCI_DEVICE(PCI_VENDOR_ID_COMPAQ, 0xB203) }, /* iLO2 */ |
| { PCI_DEVICE(PCI_VENDOR_ID_HP, 0x3306) }, /* iLO3 */ |
| {0}, /* terminate list */ |
| }; |
| MODULE_DEVICE_TABLE(pci, hpwdt_devices); |
| |
| |
| /* |
| * Watchdog operations |
| */ |
| static void hpwdt_start(void) |
| { |
| reload = SECS_TO_TICKS(soft_margin); |
| iowrite16(reload, hpwdt_timer_reg); |
| iowrite8(0x85, hpwdt_timer_con); |
| } |
| |
| static void hpwdt_stop(void) |
| { |
| unsigned long data; |
| |
| data = ioread8(hpwdt_timer_con); |
| data &= 0xFE; |
| iowrite8(data, hpwdt_timer_con); |
| } |
| |
| static void hpwdt_ping(void) |
| { |
| iowrite16(reload, hpwdt_timer_reg); |
| } |
| |
| static int hpwdt_change_timer(int new_margin) |
| { |
| if (new_margin < 1 || new_margin > HPWDT_MAX_TIMER) { |
| pr_warn("New value passed in is invalid: %d seconds\n", |
| new_margin); |
| return -EINVAL; |
| } |
| |
| soft_margin = new_margin; |
| pr_debug("New timer passed in is %d seconds\n", new_margin); |
| reload = SECS_TO_TICKS(soft_margin); |
| |
| return 0; |
| } |
| |
| static int hpwdt_time_left(void) |
| { |
| return TICKS_TO_SECS(ioread16(hpwdt_timer_reg)); |
| } |
| |
| #ifdef CONFIG_HPWDT_NMI_DECODING |
| static int hpwdt_my_nmi(void) |
| { |
| return ioread8(hpwdt_nmistat) & 0x6; |
| } |
| |
| /* |
| * NMI Handler |
| */ |
| static int hpwdt_pretimeout(unsigned int ulReason, struct pt_regs *regs) |
| { |
| if ((ulReason == NMI_UNKNOWN) && !hpwdt_my_nmi()) |
| return NMI_DONE; |
| |
| if (allow_kdump) |
| hpwdt_stop(); |
| |
| nmi_panic(regs, "An NMI occurred. Depending on your system the reason " |
| "for the NMI is logged in any one of the following " |
| "resources:\n" |
| "1. Integrated Management Log (IML)\n" |
| "2. OA Syslog\n" |
| "3. OA Forward Progress Log\n" |
| "4. iLO Event Log"); |
| |
| return NMI_HANDLED; |
| } |
| #endif /* CONFIG_HPWDT_NMI_DECODING */ |
| |
| /* |
| * /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 { |
| pr_crit("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 const struct watchdog_info ident = { |
| .options = WDIOF_SETTIMEOUT | |
| WDIOF_KEEPALIVEPING | |
| WDIOF_MAGICCLOSE, |
| .identity = "HPE 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, options; |
| 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_SETOPTIONS: |
| ret = get_user(options, p); |
| if (ret) |
| break; |
| |
| if (options & WDIOS_DISABLECARD) |
| hpwdt_stop(); |
| |
| if (options & WDIOS_ENABLECARD) { |
| hpwdt_start(); |
| hpwdt_ping(); |
| } |
| 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; |
| |
| case WDIOC_GETTIMELEFT: |
| ret = put_user(hpwdt_time_left(), p); |
| break; |
| } |
| return ret; |
| } |
| |
| /* |
| * Kernel interfaces |
| */ |
| static const 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, |
| }; |
| |
| /* |
| * Init & Exit |
| */ |
| |
| |
| static int hpwdt_init_nmi_decoding(struct pci_dev *dev) |
| { |
| #ifdef CONFIG_HPWDT_NMI_DECODING |
| int retval; |
| /* |
| * Only one function can register for NMI_UNKNOWN |
| */ |
| retval = register_nmi_handler(NMI_UNKNOWN, hpwdt_pretimeout, 0, "hpwdt"); |
| if (retval) |
| goto error; |
| retval = register_nmi_handler(NMI_SERR, hpwdt_pretimeout, 0, "hpwdt"); |
| if (retval) |
| goto error1; |
| retval = register_nmi_handler(NMI_IO_CHECK, hpwdt_pretimeout, 0, "hpwdt"); |
| if (retval) |
| goto error2; |
| |
| dev_info(&dev->dev, |
| "HPE Watchdog Timer Driver: NMI decoding initialized" |
| ", allow kernel dump: %s (default = 1/ON)\n", |
| (allow_kdump == 0) ? "OFF" : "ON"); |
| return 0; |
| |
| error2: |
| unregister_nmi_handler(NMI_SERR, "hpwdt"); |
| error1: |
| unregister_nmi_handler(NMI_UNKNOWN, "hpwdt"); |
| error: |
| dev_warn(&dev->dev, |
| "Unable to register a die notifier (err=%d).\n", |
| retval); |
| return retval; |
| #endif /* CONFIG_HPWDT_NMI_DECODING */ |
| return 0; |
| } |
| |
| static void hpwdt_exit_nmi_decoding(void) |
| { |
| #ifdef CONFIG_HPWDT_NMI_DECODING |
| unregister_nmi_handler(NMI_UNKNOWN, "hpwdt"); |
| unregister_nmi_handler(NMI_SERR, "hpwdt"); |
| unregister_nmi_handler(NMI_IO_CHECK, "hpwdt"); |
| #endif |
| } |
| |
| static int 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. |
| * So we only support the G5 ProLiant servers and higher. |
| */ |
| if (dev->subsystem_vendor != PCI_VENDOR_ID_HP && |
| dev->subsystem_vendor != PCI_VENDOR_ID_HP_3PAR) { |
| dev_warn(&dev->dev, |
| "This server does not have an iLO2+ ASIC.\n"); |
| return -ENODEV; |
| } |
| |
| /* |
| * Ignore all auxilary iLO devices with the following PCI ID |
| */ |
| if (dev->subsystem_vendor == PCI_VENDOR_ID_HP && |
| dev->subsystem_device == 0x1979) |
| 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_nmistat = pci_mem_addr + 0x6e; |
| hpwdt_timer_reg = pci_mem_addr + 0x70; |
| hpwdt_timer_con = pci_mem_addr + 0x72; |
| |
| /* Make sure that timer is disabled until /dev/watchdog is opened */ |
| hpwdt_stop(); |
| |
| /* Make sure that we have a valid soft_margin */ |
| if (hpwdt_change_timer(soft_margin)) |
| hpwdt_change_timer(DEFAULT_MARGIN); |
| |
| /* Initialize NMI Decoding functionality */ |
| retval = hpwdt_init_nmi_decoding(dev); |
| if (retval != 0) |
| goto error_init_nmi_decoding; |
| |
| 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; |
| } |
| |
| dev_info(&dev->dev, "HPE Watchdog Timer Driver: %s" |
| ", timer margin: %d seconds (nowayout=%d).\n", |
| HPWDT_VERSION, soft_margin, nowayout); |
| return 0; |
| |
| error_misc_register: |
| hpwdt_exit_nmi_decoding(); |
| error_init_nmi_decoding: |
| pci_iounmap(dev, pci_mem_addr); |
| error_pci_iomap: |
| pci_disable_device(dev); |
| return retval; |
| } |
| |
| static void hpwdt_exit(struct pci_dev *dev) |
| { |
| if (!nowayout) |
| hpwdt_stop(); |
| |
| misc_deregister(&hpwdt_miscdev); |
| hpwdt_exit_nmi_decoding(); |
| 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 = hpwdt_exit, |
| }; |
| |
| MODULE_AUTHOR("Tom Mingarelli"); |
| MODULE_DESCRIPTION("hp watchdog driver"); |
| MODULE_LICENSE("GPL"); |
| MODULE_VERSION(HPWDT_VERSION); |
| |
| module_param(soft_margin, int, 0); |
| MODULE_PARM_DESC(soft_margin, "Watchdog timeout in seconds"); |
| |
| module_param(nowayout, bool, 0); |
| MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" |
| __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); |
| |
| #ifdef CONFIG_HPWDT_NMI_DECODING |
| module_param(allow_kdump, int, 0); |
| MODULE_PARM_DESC(allow_kdump, "Start a kernel dump after NMI occurs"); |
| #endif /* CONFIG_HPWDT_NMI_DECODING */ |
| |
| module_pci_driver(hpwdt_driver); |