diff options
| -rw-r--r-- | drivers/watchdog/Kconfig | 13 | ||||
| -rw-r--r-- | drivers/watchdog/Makefile | 1 | ||||
| -rw-r--r-- | drivers/watchdog/via_wdt.c | 267 |
3 files changed, 281 insertions, 0 deletions
diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig index 79fd606b7cd..877b107f77a 100644 --- a/drivers/watchdog/Kconfig +++ b/drivers/watchdog/Kconfig @@ -772,6 +772,19 @@ config SMSC37B787_WDT Most people will say N. +config VIA_WDT + tristate "VIA Watchdog Timer" + depends on X86 + select WATCHDOG_CORE + ---help--- + This is the driver for the hardware watchdog timer on VIA + southbridge chipset CX700, VX800/VX820 or VX855/VX875. + + To compile this driver as a module, choose M here; the module + will be called via_wdt. + + Most people will say N. + config W83627HF_WDT tristate "W83627HF/W83627DHG Watchdog Timer" depends on X86 diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile index fe893e91935..e8f479a1640 100644 --- a/drivers/watchdog/Makefile +++ b/drivers/watchdog/Makefile @@ -99,6 +99,7 @@ obj-$(CONFIG_SBC7240_WDT) += sbc7240_wdt.o obj-$(CONFIG_CPU5_WDT) += cpu5wdt.o obj-$(CONFIG_SMSC_SCH311X_WDT) += sch311x_wdt.o obj-$(CONFIG_SMSC37B787_WDT) += smsc37b787_wdt.o +obj-$(CONFIG_VIA_WDT) += via_wdt.o obj-$(CONFIG_W83627HF_WDT) += w83627hf_wdt.o obj-$(CONFIG_W83697HF_WDT) += w83697hf_wdt.o obj-$(CONFIG_W83697UG_WDT) += w83697ug_wdt.o diff --git a/drivers/watchdog/via_wdt.c b/drivers/watchdog/via_wdt.c new file mode 100644 index 00000000000..026b4bbfa0a --- /dev/null +++ b/drivers/watchdog/via_wdt.c @@ -0,0 +1,267 @@ +/* + * VIA Chipset Watchdog Driver + * + * Copyright (C) 2011 Sigfox + * License terms: GNU General Public License (GPL) version 2 + * Author: Marc Vertes <marc.vertes@sigfox.com> + * Based on a preliminary version from Harald Welte <HaraldWelte@viatech.com> + * Timer code by Wim Van Sebroeck <wim@iguana.be> + * + * Caveat: PnP must be enabled in BIOS to allow full access to watchdog + * control registers. If not, the watchdog must be configured in BIOS manually. + */ +#include <linux/device.h> +#include <linux/io.h> +#include <linux/jiffies.h> +#include <linux/module.h> +#include <linux/pci.h> +#include <linux/timer.h> +#include <linux/watchdog.h> + +/* Configuration registers relative to the pci device */ +#define VIA_WDT_MMIO_BASE 0xe8 /* MMIO region base address */ +#define VIA_WDT_CONF 0xec /* watchdog enable state */ + +/* Relevant bits for the VIA_WDT_CONF register */ +#define VIA_WDT_CONF_ENABLE 0x01 /* 1: enable watchdog */ +#define VIA_WDT_CONF_MMIO 0x02 /* 1: enable watchdog MMIO */ + +/* + * The MMIO region contains the watchog control register and the + * hardware timer counter. + */ +#define VIA_WDT_MMIO_LEN 8 /* MMIO region length in bytes */ +#define VIA_WDT_CTL 0 /* MMIO addr+0: state/control reg. */ +#define VIA_WDT_COUNT 4 /* MMIO addr+4: timer counter reg. */ + +/* Bits for the VIA_WDT_CTL register */ +#define VIA_WDT_RUNNING 0x01 /* 0: stop, 1: running */ +#define VIA_WDT_FIRED 0x02 /* 1: restarted by expired watchdog */ +#define VIA_WDT_PWROFF 0x04 /* 0: reset, 1: poweroff */ +#define VIA_WDT_DISABLED 0x08 /* 1: timer is disabled */ +#define VIA_WDT_TRIGGER 0x80 /* 1: start a new countdown */ + +/* Hardware heartbeat in seconds */ +#define WDT_HW_HEARTBEAT 1 + +/* Timer heartbeat (500ms) */ +#define WDT_HEARTBEAT (HZ/2) /* should be <= ((WDT_HW_HEARTBEAT*HZ)/2) */ + +/* User space timeout in seconds */ +#define WDT_TIMEOUT_MAX 1023 /* approx. 17 min. */ +#define WDT_TIMEOUT 60 +static int timeout = WDT_TIMEOUT; +module_param(timeout, int, 0); +MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds, between 1 and 1023 " + "(default = " __MODULE_STRING(WDT_TIMEOUT) ")"); + +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) ")"); + +static struct watchdog_device wdt_dev; +static struct resource wdt_res; +static void __iomem *wdt_mem; +static unsigned int mmio; +static void wdt_timer_tick(unsigned long data); +static DEFINE_TIMER(timer, wdt_timer_tick, 0, 0); + /* The timer that pings the watchdog */ +static unsigned long next_heartbeat; /* the next_heartbeat for the timer */ + +static inline void wdt_reset(void) +{ + unsigned int ctl = readl(wdt_mem); + + writel(ctl | VIA_WDT_TRIGGER, wdt_mem); +} + +/* + * Timer tick: the timer will make sure that the watchdog timer hardware + * is being reset in time. The conditions to do this are: + * 1) the watchog timer has been started and /dev/watchdog is open + * and there is still time left before userspace should send the + * next heartbeat/ping. (note: the internal heartbeat is much smaller + * then the external/userspace heartbeat). + * 2) the watchdog timer has been stopped by userspace. + */ +static void wdt_timer_tick(unsigned long data) +{ + if (time_before(jiffies, next_heartbeat) || + (!test_bit(WDOG_ACTIVE, &wdt_dev.status))) { + wdt_reset(); + mod_timer(&timer, jiffies + WDT_HEARTBEAT); + } else + pr_crit("I will reboot your machine !\n"); +} + +static int wdt_ping(struct watchdog_device *wdd) +{ + /* calculate when the next userspace timeout will be */ + next_heartbeat = jiffies + timeout * HZ; + return 0; +} + +static int wdt_start(struct watchdog_device *wdd) +{ + unsigned int ctl = readl(wdt_mem); + + writel(timeout, wdt_mem + VIA_WDT_COUNT); + writel(ctl | VIA_WDT_RUNNING | VIA_WDT_TRIGGER, wdt_mem); + wdt_ping(wdd); + mod_timer(&timer, jiffies + WDT_HEARTBEAT); + return 0; +} + +static int wdt_stop(struct watchdog_device *wdd) +{ + unsigned int ctl = readl(wdt_mem); + + writel(ctl & ~VIA_WDT_RUNNING, wdt_mem); + return 0; +} + +static int wdt_set_timeout(struct watchdog_device *wdd, + unsigned int new_timeout) +{ + if (new_timeout < 1 || new_timeout > WDT_TIMEOUT_MAX) + return -EINVAL; + writel(new_timeout, wdt_mem + VIA_WDT_COUNT); + timeout = new_timeout; + return 0; +} + +static const struct watchdog_info wdt_info = { + .identity = "VIA watchdog", + .options = WDIOF_CARDRESET | + WDIOF_SETTIMEOUT | + WDIOF_MAGICCLOSE | + WDIOF_KEEPALIVEPING, +}; + +static const struct watchdog_ops wdt_ops = { + .owner = THIS_MODULE, + .start = wdt_start, + .stop = wdt_stop, + .ping = wdt_ping, + .set_timeout = wdt_set_timeout, +}; + +static struct watchdog_device wdt_dev = { + .info = &wdt_info, + .ops = &wdt_ops, +}; + +static int __devinit wdt_probe(struct pci_dev *pdev, + const struct pci_device_id *ent) +{ + unsigned char conf; + int ret = -ENODEV; + + if (pci_enable_device(pdev)) { + dev_err(&pdev->dev, "cannot enable PCI device\n"); + return -ENODEV; + } + + /* + * Allocate a MMIO region which contains watchdog control register + * and counter, then configure the watchdog to use this region. + * This is possible only if PnP is properly enabled in BIOS. + * If not, the watchdog must be configured in BIOS manually. + */ + if (allocate_resource(&iomem_resource, &wdt_res, VIA_WDT_MMIO_LEN, + 0xf0000000, 0xffffff00, 0xff, NULL, NULL)) { + dev_err(&pdev->dev, "MMIO allocation failed\n"); + goto err_out_disable_device; + } + + pci_write_config_dword(pdev, VIA_WDT_MMIO_BASE, wdt_res.start); + pci_read_config_byte(pdev, VIA_WDT_CONF, &conf); + conf |= VIA_WDT_CONF_ENABLE | VIA_WDT_CONF_MMIO; + pci_write_config_byte(pdev, VIA_WDT_CONF, conf); + + pci_read_config_dword(pdev, VIA_WDT_MMIO_BASE, &mmio); + if (mmio) { + dev_info(&pdev->dev, "VIA Chipset watchdog MMIO: %x\n", mmio); + } else { + dev_err(&pdev->dev, "MMIO setting failed. Check BIOS.\n"); + goto err_out_resource; + } + + if (!request_mem_region(mmio, VIA_WDT_MMIO_LEN, "via_wdt")) { + dev_err(&pdev->dev, "MMIO region busy\n"); + goto err_out_resource; + } + + wdt_mem = ioremap(mmio, VIA_WDT_MMIO_LEN); + if (wdt_mem == NULL) { + dev_err(&pdev->dev, "cannot remap VIA wdt MMIO registers\n"); + goto err_out_release; + } + + wdt_dev.timeout = timeout; + watchdog_set_nowayout(&wdt_dev, nowayout); + if (readl(wdt_mem) & VIA_WDT_FIRED) + wdt_dev.bootstatus |= WDIOF_CARDRESET; + + ret = watchdog_register_device(&wdt_dev); + if (ret) + goto err_out_iounmap; + + /* start triggering, in case of watchdog already enabled by BIOS */ + mod_timer(&timer, jiffies + WDT_HEARTBEAT); + return 0; + +err_out_iounmap: + iounmap(wdt_mem); +err_out_release: + release_mem_region(mmio, VIA_WDT_MMIO_LEN); +err_out_resource: + release_resource(&wdt_res); +err_out_disable_device: + pci_disable_device(pdev); + return ret; +} + +static void __devexit wdt_remove(struct pci_dev *pdev) +{ + watchdog_unregister_device(&wdt_dev); + del_timer(&timer); + iounmap(wdt_mem); + release_mem_region(mmio, VIA_WDT_MMIO_LEN); + release_resource(&wdt_res); + pci_disable_device(pdev); +} + +DEFINE_PCI_DEVICE_TABLE(wdt_pci_table) = { + { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_CX700) }, + { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_VX800) }, + { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_VX855) }, + { 0 } +}; + +static struct pci_driver wdt_driver = { + .name = "via_wdt", + .id_table = wdt_pci_table, + .probe = wdt_probe, + .remove = __devexit_p(wdt_remove), +}; + +static int __init wdt_init(void) +{ + if (timeout < 1 || timeout > WDT_TIMEOUT_MAX) + timeout = WDT_TIMEOUT; + return pci_register_driver(&wdt_driver); +} + +static void __exit wdt_exit(void) +{ + pci_unregister_driver(&wdt_driver); +} + +module_init(wdt_init); +module_exit(wdt_exit); + +MODULE_AUTHOR("Marc Vertes"); +MODULE_DESCRIPTION("Driver for watchdog timer on VIA chipset"); +MODULE_LICENSE("GPL"); |