- 根目录:
- drivers
- watchdog
- iTCO_wdt.c
/*
* intel TCO Watchdog Driver
*
* (c) Copyright 2006-2011 Wim Van Sebroeck <wim@iguana.be>.
*
* 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.
*
* Neither Wim Van Sebroeck nor Iguana vzw. admit liability nor
* provide warranty for any of this software. This material is
* provided "AS-IS" and at no charge.
*
* The TCO watchdog is implemented in the following I/O controller hubs:
* (See the intel documentation on http://developer.intel.com.)
* document number 290655-003, 290677-014: 82801AA (ICH), 82801AB (ICHO)
* document number 290687-002, 298242-027: 82801BA (ICH2)
* document number 290733-003, 290739-013: 82801CA (ICH3-S)
* document number 290716-001, 290718-007: 82801CAM (ICH3-M)
* document number 290744-001, 290745-025: 82801DB (ICH4)
* document number 252337-001, 252663-008: 82801DBM (ICH4-M)
* document number 273599-001, 273645-002: 82801E (C-ICH)
* document number 252516-001, 252517-028: 82801EB (ICH5), 82801ER (ICH5R)
* document number 300641-004, 300884-013: 6300ESB
* document number 301473-002, 301474-026: 82801F (ICH6)
* document number 313082-001, 313075-006: 631xESB, 632xESB
* document number 307013-003, 307014-024: 82801G (ICH7)
* document number 322896-001, 322897-001: NM10
* document number 313056-003, 313057-017: 82801H (ICH8)
* document number 316972-004, 316973-012: 82801I (ICH9)
* document number 319973-002, 319974-002: 82801J (ICH10)
* document number 322169-001, 322170-003: 5 Series, 3400 Series (PCH)
* document number 320066-003, 320257-008: EP80597 (IICH)
* document number 324645-001, 324646-001: Cougar Point (CPT)
* document number TBD : Patsburg (PBG)
* document number TBD : DH89xxCC
* document number TBD : Panther Point
* document number TBD : Lynx Point
* document number TBD : Lynx Point-LP
*/
/*
* Includes, defines, variables, module parameters, ...
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
/* Module and version information */
#define DRV_NAME "iTCO_wdt"
#define DRV_VERSION "1.11"
/* Includes */
#include <linux/acpi.h> /* For ACPI support */
#include <linux/module.h> /* For module specific items */
#include <linux/moduleparam.h> /* For new moduleparam's */
#include <linux/types.h> /* For standard types (like size_t) */
#include <linux/errno.h> /* For the -ENODEV/... values */
#include <linux/kernel.h> /* For printk/panic/... */
#include <linux/watchdog.h> /* For the watchdog specific items */
#include <linux/init.h> /* For __init/__exit/... */
#include <linux/fs.h> /* For file operations */
#include <linux/platform_device.h> /* For platform_driver framework */
#include <linux/pci.h> /* For pci functions */
#include <linux/ioport.h> /* For io-port access */
#include <linux/spinlock.h> /* For spin_lock/spin_unlock/... */
#include <linux/uaccess.h> /* For copy_to_user/put_user/... */
#include <linux/io.h> /* For inb/outb/... */
#include <linux/platform_data/itco_wdt.h>
#include "iTCO_vendor.h"
/* Address definitions for the TCO */
/* TCO base address */
#define TCOBASE (iTCO_wdt_private.tco_res->start)
/* SMI Control and Enable Register */
#define SMI_EN (iTCO_wdt_private.smi_res->start)
#define TCO_RLD (TCOBASE + 0x00) /* TCO Timer Reload and Curr. Value */
#define TCOv1_TMR (TCOBASE + 0x01) /* TCOv1 Timer Initial Value */
#define TCO_DAT_IN (TCOBASE + 0x02) /* TCO Data In Register */
#define TCO_DAT_OUT (TCOBASE + 0x03) /* TCO Data Out Register */
#define TCO1_STS (TCOBASE + 0x04) /* TCO1 Status Register */
#define TCO2_STS (TCOBASE + 0x06) /* TCO2 Status Register */
#define TCO1_CNT (TCOBASE + 0x08) /* TCO1 Control Register */
#define TCO2_CNT (TCOBASE + 0x0a) /* TCO2 Control Register */
#define TCOv2_TMR (TCOBASE + 0x12) /* TCOv2 Timer Initial Value */
/* internal variables */
static struct { /* this is private data for the iTCO_wdt device */
/* TCO version/generation */
unsigned int iTCO_version;
struct resource *tco_res;
struct resource *smi_res;
/*
* NO_REBOOT flag is Memory-Mapped GCS register bit 5 (TCO version 2),
* or memory-mapped PMC register bit 4 (TCO version 3).
*/
struct resource *gcs_pmc_res;
unsigned long __iomem *gcs_pmc;
/* the lock for io operations */
spinlock_t io_lock;
struct platform_device *dev;
/* the PCI-device */
struct pci_dev *pdev;
/* whether or not the watchdog has been suspended */
bool suspended;
} iTCO_wdt_private;
/* module parameters */
#define WATCHDOG_TIMEOUT 30 /* 30 sec default heartbeat */
static int heartbeat = WATCHDOG_TIMEOUT; /* in seconds */
module_param(heartbeat, int, 0);
MODULE_PARM_DESC(heartbeat, "Watchdog timeout in seconds. "
"5..76 (TCO v1) or 3..614 (TCO v2), default="
__MODULE_STRING(WATCHDOG_TIMEOUT) ")");
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) ")");
static int turn_SMI_watchdog_clear_off = 1;
module_param(turn_SMI_watchdog_clear_off, int, 0);
MODULE_PARM_DESC(turn_SMI_watchdog_clear_off,
"Turn off SMI clearing watchdog (depends on TCO-version)(default=1)");
/*
* Some TCO specific functions
*/
/*
* The iTCO v1 and v2's internal timer is stored as ticks which decrement
* every 0.6 seconds. v3's internal timer is stored as seconds (some
* datasheets incorrectly state 0.6 seconds).
*/
static inline unsigned int seconds_to_ticks(int secs)
{
return iTCO_wdt_private.iTCO_version == 3 ? secs : (secs * 10) / 6;
}
static inline unsigned int ticks_to_seconds(int ticks)
{
return iTCO_wdt_private.iTCO_version == 3 ? ticks : (ticks * 6) / 10;
}
static inline u32 no_reboot_bit(void)
{
u32 enable_bit;
switch (iTCO_wdt_private.iTCO_version) {
case 3:
enable_bit = 0x00000010;
break;
case 2:
enable_bit = 0x00000020;
break;
case 4:
case 1:
default:
enable_bit = 0x00000002;
break;
}
return enable_bit;
}
static void iTCO_wdt_set_NO_REBOOT_bit(void)
{
u32 val32;
/* Set the NO_REBOOT bit: this disables reboots */
if (iTCO_wdt_private.iTCO_version >= 2) {
val32 = readl(iTCO_wdt_private.gcs_pmc);
val32 |= no_reboot_bit();
writel(val32, iTCO_wdt_private.gcs_pmc);
} else if (iTCO_wdt_private.iTCO_version == 1) {
pci_read_config_dword(iTCO_wdt_private.pdev, 0xd4, &val32);
val32 |= no_reboot_bit();
pci_write_config_dword(iTCO_wdt_private.pdev, 0xd4, val32);
}
}
static int iTCO_wdt_unset_NO_REBOOT_bit(void)
{
u32 enable_bit = no_reboot_bit();
u32 val32 = 0;
/* Unset the NO_REBOOT bit: this enables reboots */
if (iTCO_wdt_private.iTCO_version >= 2) {
val32 = readl(iTCO_wdt_private.gcs_pmc);
val32 &= ~enable_bit;
writel(val32, iTCO_wdt_private.gcs_pmc);
val32 = readl(iTCO_wdt_private.gcs_pmc);
} else if (iTCO_wdt_private.iTCO_version == 1) {
pci_read_config_dword(iTCO_wdt_private.pdev, 0xd4, &val32);
val32 &= ~enable_bit;
pci_write_config_dword(iTCO_wdt_private.pdev, 0xd4, val32);
pci_read_config_dword(iTCO_wdt_private.pdev, 0xd4, &val32);
}
if (val32 & enable_bit)
return -EIO;
return 0;
}
static int iTCO_wdt_start(struct watchdog_device *wd_dev)
{
unsigned int val;
spin_lock(&iTCO_wdt_private.io_lock);
iTCO_vendor_pre_start(iTCO_wdt_private.smi_res, wd_dev->timeout);
/* disable chipset's NO_REBOOT bit */
if (iTCO_wdt_unset_NO_REBOOT_bit()) {
spin_unlock(&iTCO_wdt_private.io_lock);
pr_err("failed to reset NO_REBOOT flag, reboot disabled by hardware/BIOS\n");
return -EIO;
}
/* Force the timer to its reload value by writing to the TCO_RLD
register */
if (iTCO_wdt_private.iTCO_version >= 2)
outw(0x01, TCO_RLD);
else if (iTCO_wdt_private.iTCO_version == 1)
outb(0x01, TCO_RLD);
/* Bit 11: TCO Timer Halt -> 0 = The TCO timer is enabled to count */
val = inw(TCO1_CNT);
val &= 0xf7ff;
outw(val, TCO1_CNT);
val = inw(TCO1_CNT);
spin_unlock(&iTCO_wdt_private.io_lock);
if (val & 0x0800)
return -1;
return 0;
}
static int iTCO_wdt_stop(struct watchdog_device *wd_dev)
{
unsigned int val;
spin_lock(&iTCO_wdt_private.io_lock);
iTCO_vendor_pre_stop(iTCO_wdt_private.smi_res);
/* Bit 11: TCO Timer Halt -> 1 = The TCO timer is disabled */
val = inw(TCO1_CNT);
val |= 0x0800;
outw(val, TCO1_CNT);
val = inw(TCO1_CNT);
/* Set the NO_REBOOT bit to prevent later reboots, just for sure */
iTCO_wdt_set_NO_REBOOT_bit();
spin_unlock(&iTCO_wdt_private.io_lock);
if ((val & 0x0800) == 0)
return -1;
return 0;
}
static int iTCO_wdt_ping(struct watchdog_device *wd_dev)
{
spin_lock(&iTCO_wdt_private.io_lock);
iTCO_vendor_pre_keepalive(iTCO_wdt_private.smi_res, wd_dev->timeout);
/* Reload the timer by writing to the TCO Timer Counter register */
if (iTCO_wdt_private.iTCO_version >= 2) {
outw(0x01, TCO_RLD);
} else if (iTCO_wdt_private.iTCO_version == 1) {
/* Reset the timeout status bit so that the timer
* needs to count down twice again before rebooting */
outw(0x0008, TCO1_STS); /* write 1 to clear bit */
outb(0x01, TCO_RLD);
}
spin_unlock(&iTCO_wdt_private.io_lock);
return 0;
}
static int iTCO_wdt_set_timeout(struct watchdog_device *wd_dev, unsigned int t)
{
unsigned int val16;
unsigned char val8;
unsigned int tmrval;
tmrval = seconds_to_ticks(t);
/* For TCO v1 the timer counts down twice before rebooting */
if (iTCO_wdt_private.iTCO_version == 1)
tmrval /= 2;
/* from the specs: */
/* "Values of 0h-3h are ignored and should not be attempted" */
if (tmrval < 0x04)
return -EINVAL;
if (((iTCO_wdt_private.iTCO_version >= 2) && (tmrval > 0x3ff)) ||
((iTCO_wdt_private.iTCO_version == 1) && (tmrval > 0x03f)))
return -EINVAL;
iTCO_vendor_pre_set_heartbeat(tmrval);
/* Write new heartbeat to watchdog */
if (iTCO_wdt_private.iTCO_version >= 2) {
spin_lock(&iTCO_wdt_private.io_lock);
val16 = inw(TCOv2_TMR);
val16 &= 0xfc00;
val16 |= tmrval;
outw(val16, TCOv2_TMR);
val16 = inw(TCOv2_TMR);
spin_unlock(&iTCO_wdt_private.io_lock);
if ((val16 & 0x3ff) != tmrval)
return -EINVAL;
} else if (iTCO_wdt_private.iTCO_version == 1) {
spin_lock(&iTCO_wdt_private.io_lock);
val8 = inb(TCOv1_TMR);
val8 &= 0xc0;
val8 |= (tmrval & 0xff);
outb(val8, TCOv1_TMR);
val8 = inb(TCOv1_TMR);
spin_unlock(&iTCO_wdt_private.io_lock);
if ((val8 & 0x3f) != tmrval)
return -EINVAL;
}
wd_dev->timeout = t;
return 0;
}
static unsigned int iTCO_wdt_get_timeleft(struct watchdog_device *wd_dev)
{
unsigned int val16;
unsigned char val8;
unsigned int time_left = 0;
/* read the TCO Timer */
if (iTCO_wdt_private.iTCO_version >= 2) {
spin_lock(&iTCO_wdt_private.io_lock);
val16 = inw(TCO_RLD);
val16 &= 0x3ff;
spin_unlock(&iTCO_wdt_private.io_lock);
time_left = ticks_to_seconds(val16);
} else if (iTCO_wdt_private.iTCO_version == 1) {
spin_lock(&iTCO_wdt_private.io_lock);
val8 = inb(TCO_RLD);
val8 &= 0x3f;
if (!(inw(TCO1_STS) & 0x0008))
val8 += (inb(TCOv1_TMR) & 0x3f);
spin_unlock(&iTCO_wdt_private.io_lock);
time_left = ticks_to_seconds(val8);
}
return time_left;
}
/*
* Kernel Interfaces
*/
static const struct watchdog_info ident = {
.options = WDIOF_SETTIMEOUT |
WDIOF_KEEPALIVEPING |
WDIOF_MAGICCLOSE,
.firmware_version = 0,
.identity = DRV_NAME,
};
static const struct watchdog_ops iTCO_wdt_ops = {
.owner = THIS_MODULE,
.start = iTCO_wdt_start,
.stop = iTCO_wdt_stop,
.ping = iTCO_wdt_ping,
.set_timeout = iTCO_wdt_set_timeout,
.get_timeleft = iTCO_wdt_get_timeleft,
};
static struct watchdog_device iTCO_wdt_watchdog_dev = {
.info = &ident,
.ops = &iTCO_wdt_ops,
};
/*
* Init & exit routines
*/
static void iTCO_wdt_cleanup(void)
{
/* Stop the timer before we leave */
if (!nowayout)
iTCO_wdt_stop(&iTCO_wdt_watchdog_dev);
/* Deregister */
watchdog_unregister_device(&iTCO_wdt_watchdog_dev);
/* release resources */
release_region(iTCO_wdt_private.tco_res->start,
resource_size(iTCO_wdt_private.tco_res));
release_region(iTCO_wdt_private.smi_res->start,
resource_size(iTCO_wdt_private.smi_res));
if (iTCO_wdt_private.iTCO_version >= 2) {
iounmap(iTCO_wdt_private.gcs_pmc);
release_mem_region(iTCO_wdt_private.gcs_pmc_res->start,
resource_size(iTCO_wdt_private.gcs_pmc_res));
}
iTCO_wdt_private.tco_res = NULL;
iTCO_wdt_private.smi_res = NULL;
iTCO_wdt_private.gcs_pmc_res = NULL;
iTCO_wdt_private.gcs_pmc = NULL;
}
static int iTCO_wdt_probe(struct platform_device *dev)
{
int ret = -ENODEV;
unsigned long val32;
struct itco_wdt_platform_data *pdata = dev_get_platdata(&dev->dev);
if (!pdata)
goto out;
spin_lock_init(&iTCO_wdt_private.io_lock);
iTCO_wdt_private.tco_res =
platform_get_resource(dev, IORESOURCE_IO, ICH_RES_IO_TCO);
if (!iTCO_wdt_private.tco_res)
goto out;
iTCO_wdt_private.smi_res =
platform_get_resource(dev, IORESOURCE_IO, ICH_RES_IO_SMI);
if (!iTCO_wdt_private.smi_res)
goto out;
iTCO_wdt_private.iTCO_version = pdata->version;
iTCO_wdt_private.dev = dev;
iTCO_wdt_private.pdev = to_pci_dev(dev->dev.parent);
/*
* Get the Memory-Mapped GCS or PMC register, we need it for the
* NO_REBOOT flag (TCO v2 and v3).
*/
if (iTCO_wdt_private.iTCO_version >= 2) {
iTCO_wdt_private.gcs_pmc_res = platform_get_resource(dev,
IORESOURCE_MEM,
ICH_RES_MEM_GCS_PMC);
if (!iTCO_wdt_private.gcs_pmc_res)
goto out;
if (!request_mem_region(iTCO_wdt_private.gcs_pmc_res->start,
resource_size(iTCO_wdt_private.gcs_pmc_res), dev->name)) {
ret = -EBUSY;
goto out;
}
iTCO_wdt_private.gcs_pmc = ioremap(iTCO_wdt_private.gcs_pmc_res->start,
resource_size(iTCO_wdt_private.gcs_pmc_res));
if (!iTCO_wdt_private.gcs_pmc) {
ret = -EIO;
goto unreg_gcs_pmc;
}
}
/* Check chipset's NO_REBOOT bit */
if (iTCO_wdt_unset_NO_REBOOT_bit() && iTCO_vendor_check_noreboot_on()) {
pr_info("unable to reset NO_REBOOT flag, device disabled by hardware/BIOS\n");
ret = -ENODEV; /* Cannot reset NO_REBOOT bit */
goto unmap_gcs_pmc;
}
/* Set the NO_REBOOT bit to prevent later reboots, just for sure */
iTCO_wdt_set_NO_REBOOT_bit();
/* The TCO logic uses the TCO_EN bit in the SMI_EN register */
if (!request_region(iTCO_wdt_private.smi_res->start,
resource_size(iTCO_wdt_private.smi_res), dev->name)) {
pr_err("I/O address 0x%04llx already in use, device disabled\n",
(u64)SMI_EN);
ret = -EBUSY;
goto unmap_gcs_pmc;
}
if (turn_SMI_watchdog_clear_off >= iTCO_wdt_private.iTCO_version) {
/*
* Bit 13: TCO_EN -> 0
* Disables TCO logic generating an SMI#
*/
val32 = inl(SMI_EN);
val32 &= 0xffffdfff; /* Turn off SMI clearing watchdog */
outl(val32, SMI_EN);
}
if (!request_region(iTCO_wdt_private.tco_res->start,
resource_size(iTCO_wdt_private.tco_res), dev->name)) {
pr_err("I/O address 0x%04llx already in use, device disabled\n",
(u64)TCOBASE);
ret = -EBUSY;
goto unreg_smi;
}
pr_info("Found a %s TCO device (Version=%d, TCOBASE=0x%04llx)\n",
pdata->name, pdata->version, (u64)TCOBASE);
/* Clear out the (probably old) status */
switch (iTCO_wdt_private.iTCO_version) {
case 4:
outw(0x0008, TCO1_STS); /* Clear the Time Out Status bit */
outw(0x0002, TCO2_STS); /* Clear SECOND_TO_STS bit */
break;
case 3:
outl(0x20008, TCO1_STS);
break;
case 2:
case 1:
default:
outw(0x0008, TCO1_STS); /* Clear the Time Out Status bit */
outw(0x0002, TCO2_STS); /* Clear SECOND_TO_STS bit */
outw(0x0004, TCO2_STS); /* Clear BOOT_STS bit */
break;
}
iTCO_wdt_watchdog_dev.bootstatus = 0;
iTCO_wdt_watchdog_dev.timeout = WATCHDOG_TIMEOUT;
watchdog_set_nowayout(&iTCO_wdt_watchdog_dev, nowayout);
iTCO_wdt_watchdog_dev.parent = &dev->dev;
/* Make sure the watchdog is not running */
iTCO_wdt_stop(&iTCO_wdt_watchdog_dev);
/* Check that the heartbeat value is within it's range;
if not reset to the default */
if (iTCO_wdt_set_timeout(&iTCO_wdt_watchdog_dev, heartbeat)) {
iTCO_wdt_set_timeout(&iTCO_wdt_watchdog_dev, WATCHDOG_TIMEOUT);
pr_info("timeout value out of range, using %d\n",
WATCHDOG_TIMEOUT);
}
ret = watchdog_register_device(&iTCO_wdt_watchdog_dev);
if (ret != 0) {
pr_err("cannot register watchdog device (err=%d)\n", ret);
goto unreg_tco;
}
pr_info("initialized. heartbeat=%d sec (nowayout=%d)\n",
heartbeat, nowayout);
return 0;
unreg_tco:
release_region(iTCO_wdt_private.tco_res->start,
resource_size(iTCO_wdt_private.tco_res));
unreg_smi:
release_region(iTCO_wdt_private.smi_res->start,
resource_size(iTCO_wdt_private.smi_res));
unmap_gcs_pmc:
if (iTCO_wdt_private.iTCO_version >= 2)
iounmap(iTCO_wdt_private.gcs_pmc);
unreg_gcs_pmc:
if (iTCO_wdt_private.iTCO_version >= 2)
release_mem_region(iTCO_wdt_private.gcs_pmc_res->start,
resource_size(iTCO_wdt_private.gcs_pmc_res));
out:
iTCO_wdt_private.tco_res = NULL;
iTCO_wdt_private.smi_res = NULL;
iTCO_wdt_private.gcs_pmc_res = NULL;
iTCO_wdt_private.gcs_pmc = NULL;
return ret;
}
static int iTCO_wdt_remove(struct platform_device *dev)
{
if (iTCO_wdt_private.tco_res || iTCO_wdt_private.smi_res)
iTCO_wdt_cleanup();
return 0;
}
static void iTCO_wdt_shutdown(struct platform_device *dev)
{
iTCO_wdt_stop(NULL);
}
#ifdef CONFIG_PM_SLEEP
/*
* Suspend-to-idle requires this, because it stops the ticks and timekeeping, so
* the watchdog cannot be pinged while in that state. In ACPI sleep states the
* watchdog is stopped by the platform firmware.
*/
#ifdef CONFIG_ACPI
static inline bool need_suspend(void)
{
return acpi_target_system_state() == ACPI_STATE_S0;
}
#else
static inline bool need_suspend(void) { return true; }
#endif
static int iTCO_wdt_suspend_noirq(struct device *dev)
{
int ret = 0;
iTCO_wdt_private.suspended = false;
if (watchdog_active(&iTCO_wdt_watchdog_dev) && need_suspend()) {
ret = iTCO_wdt_stop(&iTCO_wdt_watchdog_dev);
if (!ret)
iTCO_wdt_private.suspended = true;
}
return ret;
}
static int iTCO_wdt_resume_noirq(struct device *dev)
{
if (iTCO_wdt_private.suspended)
iTCO_wdt_start(&iTCO_wdt_watchdog_dev);
return 0;
}
static struct dev_pm_ops iTCO_wdt_pm = {
.suspend_noirq = iTCO_wdt_suspend_noirq,
.resume_noirq = iTCO_wdt_resume_noirq,
};
#define ITCO_WDT_PM_OPS (&iTCO_wdt_pm)
#else
#define ITCO_WDT_PM_OPS NULL
#endif /* CONFIG_PM_SLEEP */
static struct platform_driver iTCO_wdt_driver = {
.probe = iTCO_wdt_probe,
.remove = iTCO_wdt_remove,
.shutdown = iTCO_wdt_shutdown,
.driver = {
.name = DRV_NAME,
.pm = ITCO_WDT_PM_OPS,
},
};
static int __init iTCO_wdt_init_module(void)
{
int err;
pr_info("Intel TCO WatchDog Timer Driver v%s\n", DRV_VERSION);
err = platform_driver_register(&iTCO_wdt_driver);
if (err)
return err;
return 0;
}
static void __exit iTCO_wdt_cleanup_module(void)
{
platform_driver_unregister(&iTCO_wdt_driver);
pr_info("Watchdog Module Unloaded\n");
}
module_init(iTCO_wdt_init_module);
module_exit(iTCO_wdt_cleanup_module);
MODULE_AUTHOR("Wim Van Sebroeck <wim@iguana.be>");
MODULE_DESCRIPTION("Intel TCO WatchDog Timer Driver");
MODULE_VERSION(DRV_VERSION);
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:" DRV_NAME);