summaryrefslogtreecommitdiffstats
path: root/drivers/watchdog/wdt_pci.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/watchdog/wdt_pci.c')
-rw-r--r--drivers/watchdog/wdt_pci.c742
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..d5e56b601
--- /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;
+}
+
+/**
+ * wdtpci_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");