diff options
Diffstat (limited to 'drivers/watchdog/wdt_pci.c')
| -rw-r--r-- | drivers/watchdog/wdt_pci.c | 742 |
1 files changed, 742 insertions, 0 deletions
diff --git a/drivers/watchdog/wdt_pci.c b/drivers/watchdog/wdt_pci.c new file mode 100644 index 000000000..c3254ba5a --- /dev/null +++ b/drivers/watchdog/wdt_pci.c @@ -0,0 +1,742 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Industrial Computer Source PCI-WDT500/501 driver + * + * (c) Copyright 1996-1997 Alan Cox <alan@lxorguk.ukuu.org.uk>, + * All Rights Reserved. + * + * Neither Alan Cox nor CymruNet Ltd. admit liability nor provide + * warranty for any of this software. This material is provided + * "AS-IS" and at no charge. + * + * (c) Copyright 1995 Alan Cox <alan@lxorguk.ukuu.org.uk> + * + * Release 0.10. + * + * Fixes + * Dave Gregorich : Modularisation and minor bugs + * Alan Cox : Added the watchdog ioctl() stuff + * Alan Cox : Fixed the reboot problem (as noted by + * Matt Crocker). + * Alan Cox : Added wdt= boot option + * Alan Cox : Cleaned up copy/user stuff + * Tim Hockin : Added insmod parameters, comment cleanup + * Parameterized timeout + * JP Nollmann : Added support for PCI wdt501p + * Alan Cox : Split ISA and PCI cards into two drivers + * Jeff Garzik : PCI cleanups + * Tigran Aivazian : Restructured wdtpci_init_one() to handle + * failures + * Joel Becker : Added WDIOC_GET/SETTIMEOUT + * Zwane Mwaikambo : Magic char closing, locking changes, + * cleanups + * Matt Domsch : nowayout module option + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/interrupt.h> +#include <linux/module.h> +#include <linux/moduleparam.h> +#include <linux/types.h> +#include <linux/miscdevice.h> +#include <linux/watchdog.h> +#include <linux/ioport.h> +#include <linux/delay.h> +#include <linux/notifier.h> +#include <linux/reboot.h> +#include <linux/fs.h> +#include <linux/pci.h> +#include <linux/io.h> +#include <linux/uaccess.h> + + +#define WDT_IS_PCI +#include "wd501p.h" + +/* We can only use 1 card due to the /dev/watchdog restriction */ +static int dev_count; + +static unsigned long open_lock; +static DEFINE_SPINLOCK(wdtpci_lock); +static char expect_close; + +static resource_size_t io; +static int irq; + +/* Default timeout */ +#define WD_TIMO 60 /* Default heartbeat = 60 seconds */ + +static int heartbeat = WD_TIMO; +static int wd_heartbeat; +module_param(heartbeat, int, 0); +MODULE_PARM_DESC(heartbeat, + "Watchdog heartbeat in seconds. (0<heartbeat<65536, default=" + __MODULE_STRING(WD_TIMO) ")"); + +static bool nowayout = WATCHDOG_NOWAYOUT; +module_param(nowayout, bool, 0); +MODULE_PARM_DESC(nowayout, + "Watchdog cannot be stopped once started (default=" + __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); + +/* Support for the Fan Tachometer on the PCI-WDT501 */ +static int tachometer; +module_param(tachometer, int, 0); +MODULE_PARM_DESC(tachometer, + "PCI-WDT501 Fan Tachometer support (0=disable, default=0)"); + +static int type = 500; +module_param(type, int, 0); +MODULE_PARM_DESC(type, + "PCI-WDT501 Card type (500 or 501 , default=500)"); + +/* + * Programming support + */ + +static void wdtpci_ctr_mode(int ctr, int mode) +{ + ctr <<= 6; + ctr |= 0x30; + ctr |= (mode << 1); + outb(ctr, WDT_CR); + udelay(8); +} + +static void wdtpci_ctr_load(int ctr, int val) +{ + outb(val & 0xFF, WDT_COUNT0 + ctr); + udelay(8); + outb(val >> 8, WDT_COUNT0 + ctr); + udelay(8); +} + +/** + * wdtpci_start: + * + * Start the watchdog driver. + */ + +static int wdtpci_start(void) +{ + unsigned long flags; + + spin_lock_irqsave(&wdtpci_lock, flags); + + /* + * "pet" the watchdog, as Access says. + * This resets the clock outputs. + */ + inb(WDT_DC); /* Disable watchdog */ + udelay(8); + wdtpci_ctr_mode(2, 0); /* Program CTR2 for Mode 0: + Pulse on Terminal Count */ + outb(0, WDT_DC); /* Enable watchdog */ + udelay(8); + inb(WDT_DC); /* Disable watchdog */ + udelay(8); + outb(0, WDT_CLOCK); /* 2.0833MHz clock */ + udelay(8); + inb(WDT_BUZZER); /* disable */ + udelay(8); + inb(WDT_OPTONOTRST); /* disable */ + udelay(8); + inb(WDT_OPTORST); /* disable */ + udelay(8); + inb(WDT_PROGOUT); /* disable */ + udelay(8); + wdtpci_ctr_mode(0, 3); /* Program CTR0 for Mode 3: + Square Wave Generator */ + wdtpci_ctr_mode(1, 2); /* Program CTR1 for Mode 2: + Rate Generator */ + wdtpci_ctr_mode(2, 1); /* Program CTR2 for Mode 1: + Retriggerable One-Shot */ + wdtpci_ctr_load(0, 20833); /* count at 100Hz */ + wdtpci_ctr_load(1, wd_heartbeat);/* Heartbeat */ + /* DO NOT LOAD CTR2 on PCI card! -- JPN */ + outb(0, WDT_DC); /* Enable watchdog */ + udelay(8); + + spin_unlock_irqrestore(&wdtpci_lock, flags); + return 0; +} + +/** + * wdtpci_stop: + * + * Stop the watchdog driver. + */ + +static int wdtpci_stop(void) +{ + unsigned long flags; + + /* Turn the card off */ + spin_lock_irqsave(&wdtpci_lock, flags); + inb(WDT_DC); /* Disable watchdog */ + udelay(8); + wdtpci_ctr_load(2, 0); /* 0 length reset pulses now */ + spin_unlock_irqrestore(&wdtpci_lock, flags); + return 0; +} + +/** + * wdtpci_ping: + * + * Reload counter one with the watchdog heartbeat. We don't bother + * reloading the cascade counter. + */ + +static int wdtpci_ping(void) +{ + unsigned long flags; + + spin_lock_irqsave(&wdtpci_lock, flags); + /* Write a watchdog value */ + inb(WDT_DC); /* Disable watchdog */ + udelay(8); + wdtpci_ctr_mode(1, 2); /* Re-Program CTR1 for Mode 2: + Rate Generator */ + wdtpci_ctr_load(1, wd_heartbeat);/* Heartbeat */ + outb(0, WDT_DC); /* Enable watchdog */ + udelay(8); + spin_unlock_irqrestore(&wdtpci_lock, flags); + return 0; +} + +/** + * wdtpci_set_heartbeat: + * @t: the new heartbeat value that needs to be set. + * + * Set a new heartbeat value for the watchdog device. If the heartbeat + * value is incorrect we keep the old value and return -EINVAL. + * If successful we return 0. + */ +static int wdtpci_set_heartbeat(int t) +{ + /* Arbitrary, can't find the card's limits */ + if (t < 1 || t > 65535) + return -EINVAL; + + heartbeat = t; + wd_heartbeat = t * 100; + return 0; +} + +/** + * wdtpci_get_status: + * @status: the new status. + * + * Extract the status information from a WDT watchdog device. There are + * several board variants so we have to know which bits are valid. Some + * bits default to one and some to zero in order to be maximally painful. + * + * we then map the bits onto the status ioctl flags. + */ + +static int wdtpci_get_status(int *status) +{ + unsigned char new_status; + unsigned long flags; + + spin_lock_irqsave(&wdtpci_lock, flags); + new_status = inb(WDT_SR); + spin_unlock_irqrestore(&wdtpci_lock, flags); + + *status = 0; + if (new_status & WDC_SR_ISOI0) + *status |= WDIOF_EXTERN1; + if (new_status & WDC_SR_ISII1) + *status |= WDIOF_EXTERN2; + if (type == 501) { + if (!(new_status & WDC_SR_TGOOD)) + *status |= WDIOF_OVERHEAT; + if (!(new_status & WDC_SR_PSUOVER)) + *status |= WDIOF_POWEROVER; + if (!(new_status & WDC_SR_PSUUNDR)) + *status |= WDIOF_POWERUNDER; + if (tachometer) { + if (!(new_status & WDC_SR_FANGOOD)) + *status |= WDIOF_FANFAULT; + } + } + return 0; +} + +/** + * wdtpci_get_temperature: + * + * Reports the temperature in degrees Fahrenheit. The API is in + * farenheit. It was designed by an imperial measurement luddite. + */ + +static int wdtpci_get_temperature(int *temperature) +{ + unsigned short c; + unsigned long flags; + spin_lock_irqsave(&wdtpci_lock, flags); + c = inb(WDT_RT); + udelay(8); + spin_unlock_irqrestore(&wdtpci_lock, flags); + *temperature = (c * 11 / 15) + 7; + return 0; +} + +/** + * wdtpci_interrupt: + * @irq: Interrupt number + * @dev_id: Unused as we don't allow multiple devices. + * + * Handle an interrupt from the board. These are raised when the status + * map changes in what the board considers an interesting way. That means + * a failure condition occurring. + */ + +static irqreturn_t wdtpci_interrupt(int irq, void *dev_id) +{ + /* + * Read the status register see what is up and + * then printk it. + */ + unsigned char status; + + spin_lock(&wdtpci_lock); + + status = inb(WDT_SR); + udelay(8); + + pr_crit("status %d\n", status); + + if (type == 501) { + if (!(status & WDC_SR_TGOOD)) { + pr_crit("Overheat alarm (%d)\n", inb(WDT_RT)); + udelay(8); + } + if (!(status & WDC_SR_PSUOVER)) + pr_crit("PSU over voltage\n"); + if (!(status & WDC_SR_PSUUNDR)) + pr_crit("PSU under voltage\n"); + if (tachometer) { + if (!(status & WDC_SR_FANGOOD)) + pr_crit("Possible fan fault\n"); + } + } + if (!(status & WDC_SR_WCCR)) { +#ifdef SOFTWARE_REBOOT +#ifdef ONLY_TESTING + pr_crit("Would Reboot\n"); +#else + pr_crit("Initiating system reboot\n"); + emergency_restart(); +#endif +#else + pr_crit("Reset in 5ms\n"); +#endif + } + spin_unlock(&wdtpci_lock); + return IRQ_HANDLED; +} + + +/** + * wdtpci_write: + * @file: file handle to the watchdog + * @buf: buffer to write (unused as data does not matter here + * @count: count of bytes + * @ppos: pointer to the position to write. No seeks allowed + * + * A write to a watchdog device is defined as a keepalive signal. Any + * write of data will do, as we we don't define content meaning. + */ + +static ssize_t wdtpci_write(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + if (count) { + if (!nowayout) { + size_t i; + + /* In case it was set long ago */ + expect_close = 0; + + for (i = 0; i != count; i++) { + char c; + if (get_user(c, buf + i)) + return -EFAULT; + if (c == 'V') + expect_close = 42; + } + } + wdtpci_ping(); + } + return count; +} + +/** + * wdtpci_ioctl: + * @file: file handle to the device + * @cmd: watchdog command + * @arg: argument pointer + * + * The watchdog API defines a common set of functions for all watchdogs + * according to their available features. We only actually usefully support + * querying capabilities and current status. + */ + +static long wdtpci_ioctl(struct file *file, unsigned int cmd, + unsigned long arg) +{ + void __user *argp = (void __user *)arg; + int __user *p = argp; + int new_heartbeat; + int status; + + struct watchdog_info ident = { + .options = WDIOF_SETTIMEOUT| + WDIOF_MAGICCLOSE| + WDIOF_KEEPALIVEPING, + .firmware_version = 1, + .identity = "PCI-WDT500/501", + }; + + /* Add options according to the card we have */ + ident.options |= (WDIOF_EXTERN1|WDIOF_EXTERN2); + if (type == 501) { + ident.options |= (WDIOF_OVERHEAT|WDIOF_POWERUNDER| + WDIOF_POWEROVER); + if (tachometer) + ident.options |= WDIOF_FANFAULT; + } + + switch (cmd) { + case WDIOC_GETSUPPORT: + return copy_to_user(argp, &ident, sizeof(ident)) ? -EFAULT : 0; + case WDIOC_GETSTATUS: + wdtpci_get_status(&status); + return put_user(status, p); + case WDIOC_GETBOOTSTATUS: + return put_user(0, p); + case WDIOC_KEEPALIVE: + wdtpci_ping(); + return 0; + case WDIOC_SETTIMEOUT: + if (get_user(new_heartbeat, p)) + return -EFAULT; + if (wdtpci_set_heartbeat(new_heartbeat)) + return -EINVAL; + wdtpci_ping(); + fallthrough; + case WDIOC_GETTIMEOUT: + return put_user(heartbeat, p); + default: + return -ENOTTY; + } +} + +/** + * wdtpci_open: + * @inode: inode of device + * @file: file handle to device + * + * The watchdog device has been opened. The watchdog device is single + * open and on opening we load the counters. Counter zero is a 100Hz + * cascade, into counter 1 which downcounts to reboot. When the counter + * triggers counter 2 downcounts the length of the reset pulse which + * set set to be as long as possible. + */ + +static int wdtpci_open(struct inode *inode, struct file *file) +{ + if (test_and_set_bit(0, &open_lock)) + return -EBUSY; + + if (nowayout) + __module_get(THIS_MODULE); + /* + * Activate + */ + wdtpci_start(); + return stream_open(inode, file); +} + +/** + * wdtpci_release: + * @inode: inode to board + * @file: file handle to board + * + * The watchdog has a configurable API. There is a religious dispute + * between people who want their watchdog to be able to shut down and + * those who want to be sure if the watchdog manager dies the machine + * reboots. In the former case we disable the counters, in the latter + * case you have to open it again very soon. + */ + +static int wdtpci_release(struct inode *inode, struct file *file) +{ + if (expect_close == 42) { + wdtpci_stop(); + } else { + pr_crit("Unexpected close, not stopping timer!\n"); + wdtpci_ping(); + } + expect_close = 0; + clear_bit(0, &open_lock); + return 0; +} + +/** + * wdtpci_temp_read: + * @file: file handle to the watchdog board + * @buf: buffer to write 1 byte into + * @count: length of buffer + * @ptr: offset (no seek allowed) + * + * Read reports the temperature in degrees Fahrenheit. The API is in + * fahrenheit. It was designed by an imperial measurement luddite. + */ + +static ssize_t wdtpci_temp_read(struct file *file, char __user *buf, + size_t count, loff_t *ptr) +{ + int temperature; + + if (wdtpci_get_temperature(&temperature)) + return -EFAULT; + + if (copy_to_user(buf, &temperature, 1)) + return -EFAULT; + + return 1; +} + +/** + * wdtpci_temp_open: + * @inode: inode of device + * @file: file handle to device + * + * The temperature device has been opened. + */ + +static int wdtpci_temp_open(struct inode *inode, struct file *file) +{ + return stream_open(inode, file); +} + +/** + * wdtpci_temp_release: + * @inode: inode to board + * @file: file handle to board + * + * The temperature device has been closed. + */ + +static int wdtpci_temp_release(struct inode *inode, struct file *file) +{ + return 0; +} + +/** + * notify_sys: + * @this: our notifier block + * @code: the event being reported + * @unused: unused + * + * Our notifier is called on system shutdowns. We want to turn the card + * off at reboot otherwise the machine will reboot again during memory + * test or worse yet during the following fsck. This would suck, in fact + * trust me - if it happens it does suck. + */ + +static int wdtpci_notify_sys(struct notifier_block *this, unsigned long code, + void *unused) +{ + if (code == SYS_DOWN || code == SYS_HALT) + wdtpci_stop(); + return NOTIFY_DONE; +} + +/* + * Kernel Interfaces + */ + + +static const struct file_operations wdtpci_fops = { + .owner = THIS_MODULE, + .llseek = no_llseek, + .write = wdtpci_write, + .unlocked_ioctl = wdtpci_ioctl, + .compat_ioctl = compat_ptr_ioctl, + .open = wdtpci_open, + .release = wdtpci_release, +}; + +static struct miscdevice wdtpci_miscdev = { + .minor = WATCHDOG_MINOR, + .name = "watchdog", + .fops = &wdtpci_fops, +}; + +static const struct file_operations wdtpci_temp_fops = { + .owner = THIS_MODULE, + .llseek = no_llseek, + .read = wdtpci_temp_read, + .open = wdtpci_temp_open, + .release = wdtpci_temp_release, +}; + +static struct miscdevice temp_miscdev = { + .minor = TEMP_MINOR, + .name = "temperature", + .fops = &wdtpci_temp_fops, +}; + +/* + * The WDT card needs to learn about soft shutdowns in order to + * turn the timebomb registers off. + */ + +static struct notifier_block wdtpci_notifier = { + .notifier_call = wdtpci_notify_sys, +}; + + +static int wdtpci_init_one(struct pci_dev *dev, + const struct pci_device_id *ent) +{ + int ret = -EIO; + + dev_count++; + if (dev_count > 1) { + pr_err("This driver only supports one device\n"); + return -ENODEV; + } + + if (type != 500 && type != 501) { + pr_err("unknown card type '%d'\n", type); + return -ENODEV; + } + + if (pci_enable_device(dev)) { + pr_err("Not possible to enable PCI Device\n"); + return -ENODEV; + } + + if (pci_resource_start(dev, 2) == 0x0000) { + pr_err("No I/O-Address for card detected\n"); + ret = -ENODEV; + goto out_pci; + } + + if (pci_request_region(dev, 2, "wdt_pci")) { + pr_err("I/O address 0x%llx already in use\n", + (unsigned long long)pci_resource_start(dev, 2)); + goto out_pci; + } + + irq = dev->irq; + io = pci_resource_start(dev, 2); + + if (request_irq(irq, wdtpci_interrupt, IRQF_SHARED, + "wdt_pci", &wdtpci_miscdev)) { + pr_err("IRQ %d is not free\n", irq); + goto out_reg; + } + + pr_info("PCI-WDT500/501 (PCI-WDG-CSM) driver 0.10 at 0x%llx (Interrupt %d)\n", + (unsigned long long)io, irq); + + /* Check that the heartbeat value is within its range; + if not reset to the default */ + if (wdtpci_set_heartbeat(heartbeat)) { + wdtpci_set_heartbeat(WD_TIMO); + pr_info("heartbeat value must be 0 < heartbeat < 65536, using %d\n", + WD_TIMO); + } + + ret = register_reboot_notifier(&wdtpci_notifier); + if (ret) { + pr_err("cannot register reboot notifier (err=%d)\n", ret); + goto out_irq; + } + + if (type == 501) { + ret = misc_register(&temp_miscdev); + if (ret) { + pr_err("cannot register miscdev on minor=%d (err=%d)\n", + TEMP_MINOR, ret); + goto out_rbt; + } + } + + ret = misc_register(&wdtpci_miscdev); + if (ret) { + pr_err("cannot register miscdev on minor=%d (err=%d)\n", + WATCHDOG_MINOR, ret); + goto out_misc; + } + + pr_info("initialized. heartbeat=%d sec (nowayout=%d)\n", + heartbeat, nowayout); + if (type == 501) + pr_info("Fan Tachometer is %s\n", + tachometer ? "Enabled" : "Disabled"); + + ret = 0; +out: + return ret; + +out_misc: + if (type == 501) + misc_deregister(&temp_miscdev); +out_rbt: + unregister_reboot_notifier(&wdtpci_notifier); +out_irq: + free_irq(irq, &wdtpci_miscdev); +out_reg: + pci_release_region(dev, 2); +out_pci: + pci_disable_device(dev); + goto out; +} + + +static void wdtpci_remove_one(struct pci_dev *pdev) +{ + /* here we assume only one device will ever have + * been picked up and registered by probe function */ + misc_deregister(&wdtpci_miscdev); + if (type == 501) + misc_deregister(&temp_miscdev); + unregister_reboot_notifier(&wdtpci_notifier); + free_irq(irq, &wdtpci_miscdev); + pci_release_region(pdev, 2); + pci_disable_device(pdev); + dev_count--; +} + + +static const struct pci_device_id wdtpci_pci_tbl[] = { + { + .vendor = PCI_VENDOR_ID_ACCESSIO, + .device = PCI_DEVICE_ID_ACCESSIO_WDG_CSM, + .subvendor = PCI_ANY_ID, + .subdevice = PCI_ANY_ID, + }, + { 0, }, /* terminate list */ +}; +MODULE_DEVICE_TABLE(pci, wdtpci_pci_tbl); + + +static struct pci_driver wdtpci_driver = { + .name = "wdt_pci", + .id_table = wdtpci_pci_tbl, + .probe = wdtpci_init_one, + .remove = wdtpci_remove_one, +}; + +module_pci_driver(wdtpci_driver); + +MODULE_AUTHOR("JP Nollmann, Alan Cox"); +MODULE_DESCRIPTION("Driver for the ICS PCI-WDT500/501 watchdog cards"); +MODULE_LICENSE("GPL"); |