--- /dev/null
+/*
+ * nv_tco 0.01: TCO timer driver for NV chipsets
+ *
+ * (c) Copyright 2005 Google Inc., All Rights Reserved.
+ *
+ * Based off i8xx_tco.c:
+ * (c) Copyright 2000 kernel concepts <nils@kernelconcepts.de>, All Rights
+ * Reserved.
+ * http://www.kernelconcepts.de
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ *
+ * TCO timer driver for NV chipsets
+ * based on softdog.c by Alan Cox <alan@redhat.com>
+ */
+
+/*
+ * Includes, defines, variables, module parameters, ...
+ */
+
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/types.h>
+#include <linux/miscdevice.h>
+#include <linux/watchdog.h>
+#include <linux/init.h>
+#include <linux/fs.h>
+#include <linux/pci.h>
+#include <linux/ioport.h>
+#include <linux/jiffies.h>
+#include <linux/platform_device.h>
+#include <linux/uaccess.h>
+#include <linux/io.h>
+
+#include "nv_tco.h"
+
+/* Module and version information */
+#define TCO_VERSION "0.01"
+#define TCO_MODULE_NAME "NV_TCO"
+#define TCO_DRIVER_NAME TCO_MODULE_NAME ", v" TCO_VERSION
+#define PFX TCO_MODULE_NAME ": "
+
+/* internal variables */
+static unsigned int tcobase;
+static DEFINE_SPINLOCK(tco_lock); /* Guards the hardware */
+static unsigned long timer_alive;
+static char tco_expect_close;
+static struct pci_dev *tco_pci;
+
+/* the watchdog platform device */
+static struct platform_device *nv_tco_platform_device;
+
+/* module parameters */
+#define WATCHDOG_HEARTBEAT 30 /* 30 sec default heartbeat (2<heartbeat<39) */
+static int heartbeat = WATCHDOG_HEARTBEAT; /* in seconds */
+module_param(heartbeat, int, 0);
+MODULE_PARM_DESC(heartbeat, "Watchdog heartbeat in seconds. (2<heartbeat<39, "
+ "default=" __MODULE_STRING(WATCHDOG_HEARTBEAT) ")");
+
+static int nowayout = WATCHDOG_NOWAYOUT;
+module_param(nowayout, int, 0);
+MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started"
+ " (default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
+
+/*
+ * Some TCO specific functions
+ */
+static inline unsigned char seconds_to_ticks(int seconds)
+{
+ /* the internal timer is stored as ticks which decrement
+ * every 0.6 seconds */
+ return (seconds * 10) / 6;
+}
+
+static void tco_timer_start(void)
+{
+ u32 val;
+ unsigned long flags;
+
+ spin_lock_irqsave(&tco_lock, flags);
+ val = inl(TCO_CNT(tcobase));
+ val &= ~TCO_CNT_TCOHALT;
+ outl(val, TCO_CNT(tcobase));
+ spin_unlock_irqrestore(&tco_lock, flags);
+}
+
+static void tco_timer_stop(void)
+{
+ u32 val;
+ unsigned long flags;
+
+ spin_lock_irqsave(&tco_lock, flags);
+ val = inl(TCO_CNT(tcobase));
+ val |= TCO_CNT_TCOHALT;
+ outl(val, TCO_CNT(tcobase));
+ spin_unlock_irqrestore(&tco_lock, flags);
+}
+
+static void tco_timer_keepalive(void)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&tco_lock, flags);
+ outb(0x01, TCO_RLD(tcobase));
+ spin_unlock_irqrestore(&tco_lock, flags);
+}
+
+static int tco_timer_set_heartbeat(int t)
+{
+ int ret = 0;
+ unsigned char tmrval;
+ unsigned long flags;
+ u8 val;
+
+ /*
+ * note seconds_to_ticks(t) > t, so if t > 0x3f, so is
+ * tmrval=seconds_to_ticks(t). Check that the count in seconds isn't
+ * out of range on it's own (to avoid overflow in tmrval).
+ */
+ if (t < 0 || t > 0x3f)
+ return -EINVAL;
+ tmrval = seconds_to_ticks(t);
+
+ /* "Values of 0h-3h are ignored and should not be attempted" */
+ if (tmrval > 0x3f || tmrval < 0x04)
+ return -EINVAL;
+
+ /* Write new heartbeat to watchdog */
+ spin_lock_irqsave(&tco_lock, flags);
+ val = inb(TCO_TMR(tcobase));
+ val &= 0xc0;
+ val |= tmrval;
+ outb(val, TCO_TMR(tcobase));
+ val = inb(TCO_TMR(tcobase));
+
+ if ((val & 0x3f) != tmrval)
+ ret = -EINVAL;
+ spin_unlock_irqrestore(&tco_lock, flags);
+
+ if (ret)
+ return ret;
+
+ heartbeat = t;
+ return 0;
+}
+
+/*
+ * /dev/watchdog handling
+ */
+
+static int nv_tco_open(struct inode *inode, struct file *file)
+{
+ /* /dev/watchdog can only be opened once */
+ if (test_and_set_bit(0, &timer_alive))
+ return -EBUSY;
+
+ /* Reload and activate timer */
+ tco_timer_keepalive();
+ tco_timer_start();
+ return nonseekable_open(inode, file);
+}
+
+static int nv_tco_release(struct inode *inode, struct file *file)
+{
+ /* Shut off the timer */
+ if (tco_expect_close == 42) {
+ tco_timer_stop();
+ } else {
+ printk(KERN_CRIT PFX "Unexpected close, not stopping "
+ "watchdog!\n");
+ tco_timer_keepalive();
+ }
+ clear_bit(0, &timer_alive);
+ tco_expect_close = 0;
+ return 0;
+}
+
+static ssize_t nv_tco_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...
+ */
+ tco_expect_close = 0;
+
+ /*
+ * scan to see whether or not we got the magic
+ * character
+ */
+ for (i = 0; i != len; i++) {
+ char c;
+ if (get_user(c, data + i))
+ return -EFAULT;
+ if (c == 'V')
+ tco_expect_close = 42;
+ }
+ }
+
+ /* someone wrote to us, we should reload the timer */
+ tco_timer_keepalive();
+ }
+ return len;
+}
+
+static long nv_tco_ioctl(struct file *file, unsigned int cmd,
+ unsigned long arg)
+{
+ int new_options, retval = -EINVAL;
+ int new_heartbeat;
+ void __user *argp = (void __user *)arg;
+ int __user *p = argp;
+ static const struct watchdog_info ident = {
+ .options = WDIOF_SETTIMEOUT |
+ WDIOF_KEEPALIVEPING |
+ WDIOF_MAGICCLOSE,
+ .firmware_version = 0,
+ .identity = TCO_MODULE_NAME,
+ };
+
+ switch (cmd) {
+ case WDIOC_GETSUPPORT:
+ return copy_to_user(argp, &ident, sizeof(ident)) ? -EFAULT : 0;
+ case WDIOC_GETSTATUS:
+ case WDIOC_GETBOOTSTATUS:
+ return put_user(0, p);
+ case WDIOC_SETOPTIONS:
+ if (get_user(new_options, p))
+ return -EFAULT;
+ if (new_options & WDIOS_DISABLECARD) {
+ tco_timer_stop();
+ retval = 0;
+ }
+ if (new_options & WDIOS_ENABLECARD) {
+ tco_timer_keepalive();
+ tco_timer_start();
+ retval = 0;
+ }
+ return retval;
+ case WDIOC_KEEPALIVE:
+ tco_timer_keepalive();
+ return 0;
+ case WDIOC_SETTIMEOUT:
+ if (get_user(new_heartbeat, p))
+ return -EFAULT;
+ if (tco_timer_set_heartbeat(new_heartbeat))
+ return -EINVAL;
+ tco_timer_keepalive();
+ /* Fall through */
+ case WDIOC_GETTIMEOUT:
+ return put_user(heartbeat, p);
+ default:
+ return -ENOTTY;
+ }
+}
+
+/*
+ * Kernel Interfaces
+ */
+
+static const struct file_operations nv_tco_fops = {
+ .owner = THIS_MODULE,
+ .llseek = no_llseek,
+ .write = nv_tco_write,
+ .unlocked_ioctl = nv_tco_ioctl,
+ .open = nv_tco_open,
+ .release = nv_tco_release,
+};
+
+static struct miscdevice nv_tco_miscdev = {
+ .minor = WATCHDOG_MINOR,
+ .name = "watchdog",
+ .fops = &nv_tco_fops,
+};
+
+/*
+ * Data for PCI driver interface
+ *
+ * This data only exists for exporting the supported
+ * PCI ids via MODULE_DEVICE_TABLE. We do not actually
+ * register a pci_driver, because someone else might one day
+ * want to register another driver on the same PCI id.
+ */
+static struct pci_device_id tco_pci_tbl[] = {
+ { PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP51_SMBUS,
+ PCI_ANY_ID, PCI_ANY_ID, },
+ { PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP55_SMBUS,
+ PCI_ANY_ID, PCI_ANY_ID, },
+ { 0, }, /* End of list */
+};
+MODULE_DEVICE_TABLE(pci, tco_pci_tbl);
+
+/*
+ * Init & exit routines
+ */
+
+static unsigned char __init nv_tco_getdevice(void)
+{
+ struct pci_dev *dev = NULL;
+ u32 val;
+
+ /* Find the PCI device */
+ for_each_pci_dev(dev) {
+ if (pci_match_id(tco_pci_tbl, dev) != NULL) {
+ tco_pci = dev;
+ break;
+ }
+ }
+
+ if (!tco_pci)
+ return 0;
+
+ /* Find the base io port */
+ pci_read_config_dword(tco_pci, 0x64, &val);
+ val &= 0xffff;
+ if (val == 0x0001 || val == 0x0000) {
+ /* Something is wrong here, bar isn't setup */
+ printk(KERN_ERR PFX "failed to get tcobase address\n");
+ return 0;
+ }
+ val &= 0xff00;
+ tcobase = val + 0x40;
+
+ if (!request_region(tcobase, 0x10, "NV TCO")) {
+ printk(KERN_ERR PFX "I/O address 0x%04x already in use\n",
+ tcobase);
+ return 0;
+ }
+
+ /* Set a reasonable heartbeat before we stop the timer */
+ tco_timer_set_heartbeat(30);
+
+ /*
+ * Stop the TCO before we change anything so we don't race with
+ * a zeroed timer.
+ */
+ tco_timer_keepalive();
+ tco_timer_stop();
+
+ /* Disable SMI caused by TCO */
+ if (!request_region(MCP51_SMI_EN(tcobase), 4, "NV TCO")) {
+ printk(KERN_ERR PFX "I/O address 0x%04x already in use\n",
+ MCP51_SMI_EN(tcobase));
+ goto out;
+ }
+ val = inl(MCP51_SMI_EN(tcobase));
+ val &= ~MCP51_SMI_EN_TCO;
+ outl(val, MCP51_SMI_EN(tcobase));
+ val = inl(MCP51_SMI_EN(tcobase));
+ release_region(MCP51_SMI_EN(tcobase), 4);
+ if (val & MCP51_SMI_EN_TCO) {
+ printk(KERN_ERR PFX "Could not disable SMI caused by TCO\n");
+ goto out;
+ }
+
+ /* Check chipset's NO_REBOOT bit */
+ pci_read_config_dword(tco_pci, MCP51_SMBUS_SETUP_B, &val);
+ val |= MCP51_SMBUS_SETUP_B_TCO_REBOOT;
+ pci_write_config_dword(tco_pci, MCP51_SMBUS_SETUP_B, val);
+ pci_read_config_dword(tco_pci, MCP51_SMBUS_SETUP_B, &val);
+ if (!(val & MCP51_SMBUS_SETUP_B_TCO_REBOOT)) {
+ printk(KERN_ERR PFX "failed to reset NO_REBOOT flag, reboot "
+ "disabled by hardware\n");
+ goto out;
+ }
+
+ return 1;
+out:
+ release_region(tcobase, 0x10);
+ return 0;
+}
+
+static int __devinit nv_tco_init(struct platform_device *dev)
+{
+ int ret;
+
+ /* Check whether or not the hardware watchdog is there */
+ if (!nv_tco_getdevice())
+ return -ENODEV;
+
+ /* Check to see if last reboot was due to watchdog timeout */
+ printk(KERN_INFO PFX "Watchdog reboot %sdetected.\n",
+ inl(TCO_STS(tcobase)) & TCO_STS_TCO2TO_STS ? "" : "not ");
+
+ /* Clear out the old status */
+ outl(TCO_STS_RESET, TCO_STS(tcobase));
+
+ /*
+ * Check that the heartbeat value is within it's range.
+ * If not, reset to the default.
+ */
+ if (tco_timer_set_heartbeat(heartbeat)) {
+ heartbeat = WATCHDOG_HEARTBEAT;
+ tco_timer_set_heartbeat(heartbeat);
+ printk(KERN_INFO PFX "heartbeat value must be 2<heartbeat<39, "
+ "using %d\n", heartbeat);
+ }
+
+ ret = misc_register(&nv_tco_miscdev);
+ if (ret != 0) {
+ printk(KERN_ERR PFX "cannot register miscdev on minor=%d "
+ "(err=%d)\n", WATCHDOG_MINOR, ret);
+ goto unreg_region;
+ }
+
+ clear_bit(0, &timer_alive);
+
+ tco_timer_stop();
+
+ printk(KERN_INFO PFX "initialized (0x%04x). heartbeat=%d sec "
+ "(nowayout=%d)\n", tcobase, heartbeat, nowayout);
+
+ return 0;
+
+unreg_region:
+ release_region(tcobase, 0x10);
+ return ret;
+}
+
+static void __devexit nv_tco_cleanup(void)
+{
+ u32 val;
+
+ /* Stop the timer before we leave */
+ if (!nowayout)
+ tco_timer_stop();
+
+ /* Set the NO_REBOOT bit to prevent later reboots, just for sure */
+ pci_read_config_dword(tco_pci, MCP51_SMBUS_SETUP_B, &val);
+ val &= ~MCP51_SMBUS_SETUP_B_TCO_REBOOT;
+ pci_write_config_dword(tco_pci, MCP51_SMBUS_SETUP_B, val);
+ pci_read_config_dword(tco_pci, MCP51_SMBUS_SETUP_B, &val);
+ if (val & MCP51_SMBUS_SETUP_B_TCO_REBOOT) {
+ printk(KERN_CRIT PFX "Couldn't unset REBOOT bit. Machine may "
+ "soon reset\n");
+ }
+
+ /* Deregister */
+ misc_deregister(&nv_tco_miscdev);
+ release_region(tcobase, 0x10);
+}
+
+static int __devexit nv_tco_remove(struct platform_device *dev)
+{
+ if (tcobase)
+ nv_tco_cleanup();
+
+ return 0;
+}
+
+static void nv_tco_shutdown(struct platform_device *dev)
+{
+ tco_timer_stop();
+}
+
+static struct platform_driver nv_tco_driver = {
+ .probe = nv_tco_init,
+ .remove = __devexit_p(nv_tco_remove),
+ .shutdown = nv_tco_shutdown,
+ .driver = {
+ .owner = THIS_MODULE,
+ .name = TCO_MODULE_NAME,
+ },
+};
+
+static int __init nv_tco_init_module(void)
+{
+ int err;
+
+ printk(KERN_INFO PFX "NV TCO WatchDog Timer Driver v%s\n",
+ TCO_VERSION);
+
+ err = platform_driver_register(&nv_tco_driver);
+ if (err)
+ return err;
+
+ nv_tco_platform_device = platform_device_register_simple(
+ TCO_MODULE_NAME, -1, NULL, 0);
+ if (IS_ERR(nv_tco_platform_device)) {
+ err = PTR_ERR(nv_tco_platform_device);
+ goto unreg_platform_driver;
+ }
+
+ return 0;
+
+unreg_platform_driver:
+ platform_driver_unregister(&nv_tco_driver);
+ return err;
+}
+
+static void __exit nv_tco_cleanup_module(void)
+{
+ platform_device_unregister(nv_tco_platform_device);
+ platform_driver_unregister(&nv_tco_driver);
+ printk(KERN_INFO PFX "NV TCO Watchdog Module Unloaded.\n");
+}
+
+module_init(nv_tco_init_module);
+module_exit(nv_tco_cleanup_module);
+
+MODULE_AUTHOR("Mike Waychison");
+MODULE_DESCRIPTION("TCO timer driver for NV chipsets");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
projects / mv-sheeva.git / blobdiff