Message ID | 1452640232-1165-1-git-send-email-wim.coekaerts@oracle.com |
---|---|
State | Changes Requested |
Delegated to: | David Miller |
Headers | show |
Hi Wim, On Wed, Jan 13, 2016 at 10:10 AM, <wim.coekaerts@oracle.com> wrote: > From: Wim Coekaerts <wim.coekaerts@oracle.com> > > This adds a simple watchdog timer for the SPARC sunv4 architecture. > Export the sun4v_mach_set_watchdog() hv call, and add the target. > The driver was based on the same model used by the Xen watchdog driver. > > This was tested on T2, T4, T5 and T7. > > Signed-off-by: Wim Coekaerts <wim.coekaerts@oracle.com> > --- > arch/sparc/kernel/sparc_ksyms_64.c | 1 + > drivers/watchdog/Kconfig | 10 + > drivers/watchdog/Makefile | 1 + > drivers/watchdog/sun4v_wdt.c | 421 ++++++++++++++++++++++++++++++++++++ > 4 files changed, 433 insertions(+), 0 deletions(-) > create mode 100644 drivers/watchdog/sun4v_wdt.c > > diff --git a/arch/sparc/kernel/sparc_ksyms_64.c b/arch/sparc/kernel/sparc_ksyms_64.c > index a92d5d2..9e034f2 100644 > --- a/arch/sparc/kernel/sparc_ksyms_64.c > +++ b/arch/sparc/kernel/sparc_ksyms_64.c > @@ -37,6 +37,7 @@ EXPORT_SYMBOL(sun4v_niagara_getperf); > EXPORT_SYMBOL(sun4v_niagara_setperf); > EXPORT_SYMBOL(sun4v_niagara2_getperf); > EXPORT_SYMBOL(sun4v_niagara2_setperf); > +EXPORT_SYMBOL(sun4v_mach_set_watchdog); > > /* from hweight.S */ > EXPORT_SYMBOL(__arch_hweight8); > diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig > index 1c427be..08834e4 100644 > --- a/drivers/watchdog/Kconfig > +++ b/drivers/watchdog/Kconfig > @@ -1516,6 +1516,16 @@ config UML_WATCHDOG > tristate "UML watchdog" > depends on UML > > +# SPARC sun4v > + > +config WATCHDOG_SUN4V > + tristate "Sun4v Watchdog support" > + depends on SPARC64 > + help > + Say Y here to support the hypervisor watchdog capability provided > + by the sun4v architecture. The watchdog timeout period is normally one > + minute but can be changed with a boot-time parameter. > + > # > # ISA-based Watchdog Cards > # > diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile > index 53d4827..9b8acb8 100644 > --- a/drivers/watchdog/Makefile > +++ b/drivers/watchdog/Makefile > @@ -175,6 +175,7 @@ obj-$(CONFIG_SH_WDT) += shwdt.o > > obj-$(CONFIG_WATCHDOG_RIO) += riowd.o > obj-$(CONFIG_WATCHDOG_CP1XXX) += cpwd.o > +obj-$(CONFIG_WATCHDOG_SUN4V) += sun4v_wdt.o > > # XTENSA Architecture > > diff --git a/drivers/watchdog/sun4v_wdt.c b/drivers/watchdog/sun4v_wdt.c > new file mode 100644 > index 0000000..1213a1f > --- /dev/null > +++ b/drivers/watchdog/sun4v_wdt.c > @@ -0,0 +1,421 @@ > +/* > + * Sun4v Watchdog Driver > + * (c) Copyright 2015 Oracle Corporation > + * > + * Heavily modified version of xen_wdt.c > + * (c) Copyright 2010 Novell, Inc. > + * > + * Extra line? > + * 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. > + */ > + > +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt > + > +#define DRV_NAME "sun4v_wdt" > +#define DRV_VERSION "0.01" > + > +#include <linux/bug.h> > +#include <linux/errno.h> > +#include <linux/fs.h> > +#include <linux/hrtimer.h> > +#include <linux/kernel.h> > +#include <linux/ktime.h> > +#include <linux/init.h> Aren't these usually sorted alphabetically? If so, init.h should come before kernel.h. > +#include <linux/miscdevice.h> > +#include <linux/module.h> > +#include <linux/moduleparam.h> > +#include <linux/platform_device.h> > +#include <linux/spinlock.h> > +#include <linux/uaccess.h> > +#include <linux/watchdog.h> > +#include <asm/hypervisor.h> > +#include <asm/mdesc.h> > + > + Extra blank line? Have you run this through checkpatch.pl? > +static struct platform_device *platform_device; > +static DEFINE_SPINLOCK(wdt_lock); > +static __kernel_time_t wdt_expires; > +static unsigned long is_active; > +static bool expect_release; > + > +unsigned long wdt_timeout = 0; > + > +#define WATCHDOG_TIMEOUT 60 /* in seconds */ > +static unsigned long timeout = WATCHDOG_TIMEOUT; > +module_param(timeout, ulong, S_IRUGO); > +MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds " > + "(default=" __MODULE_STRING(WATCHDOG_TIMEOUT) ")"); > + > +static bool nowayout = WATCHDOG_NOWAYOUT; > +module_param(nowayout, bool, S_IRUGO); > +MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started " > + "(default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); > + > +static inline __kernel_time_t set_timeout(void) > +{ > + /* > + * The hypervisor specifies WD timeout in milliseconds > + * Change it to seconds here and > + * to do it in one place rather than every call to > + * sun4v_mach_set_watchdog() > + * The hvcall expects milliseconds while the parameters > + * and the rest of the code expects seconds. wdt_timeout > + * is the variable that we pass to the hvcall. > + */ > + wdt_timeout = timeout * 1000; > + return ktime_to_timespec(ktime_get()).tv_sec + timeout; > +} Would it be more readable to just convert the time per-call (or wrap the method) instead of this? Also, the name "set_timeout" implies that it takes a parameter to me, which makes this confusing. > + > +static int sun4v_wdt_start(void) > +{ > + __kernel_time_t expires; > + unsigned long time_remaining; > + int err; > + > + spin_lock(&wdt_lock); > + > + expires = set_timeout(); For example, here we're setting "expires" and then using wdt_timeout instead which is somewhat confusing. > + err = sun4v_mach_set_watchdog(wdt_timeout, &time_remaining); I also note that the time_remaining variable is never used. Why not something like: static inline int write_timeout() { unsigned long time_remaining; return sun4v_mach_set_watchdog(timeout * 1000, &time_remaining); } then the previous two lines would be replaced with: err = write_timeout(); > + > + spin_unlock(&wdt_lock); > + > + pr_info("Watchdog timer enabled\n"); > + return err; > +} > + > +static int sun4v_wdt_stop(void) > +{ > + int err; > + unsigned long time_remaining; > + > + spin_lock(&wdt_lock); > + > + err = sun4v_mach_set_watchdog(0, &time_remaining); > + > + spin_unlock(&wdt_lock); > + > + pr_info("Watchdog timer disabled\n"); > + return err; > +} > + > +static int sun4v_wdt_kick(void) > +{ > + __kernel_time_t expires; > + int err; > + unsigned long time_remaining; > + > + spin_lock(&wdt_lock); > + > + expires = set_timeout(); > + err = sun4v_mach_set_watchdog(wdt_timeout, &time_remaining); > + if (!err) > + wdt_expires = expires; And this could be replaced with: err = write_timeout(); if (!err) wdt_expires = ktime_to_timespec(ktime_get()).tv_sec + timeout; > + > + spin_unlock(&wdt_lock); > + > + return err; > +} > + > +static int sun4v_wdt_open(struct inode *inode, struct file *file) > +{ > + int err; > + > + /* /dev/watchdog can only be opened once */ > + if (test_and_set_bit(0, &is_active)) > + return -EBUSY; > + > + /* prevent someone from rmmod'ing the module */ > + if (nowayout) > + __module_get(THIS_MODULE); > + > + err = sun4v_wdt_start(); > + if (err == -EBUSY) { > + err = sun4v_wdt_kick(); > + } > + > + return err ?: nonseekable_open(inode, file); I've nothing against the usage of ?:, but would it be cleaner to write: if (err) return err; return nonseekable_open(inode, file); > +} > + > +static int sun4v_wdt_release(struct inode *inode, struct file *file) > +{ > + int err; > + > + if (expect_release) > + err = sun4v_wdt_stop(); > + else { > + pr_crit("Unexpected close, not stopping watchdog!\n"); > + sun4v_wdt_kick(); > + } > + > + clear_bit(0, &is_active); > + expect_release = false; > + > + return 0; > +} > + > +static ssize_t sun4v_wdt_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; > + > + /* in case it was set long ago */ > + expect_release = false; > + > + /* 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') > + expect_release = true; > + } > + } > + > + /* someone wrote to us, we should reload the timer */ > + sun4v_wdt_kick(); > + } > + return len; > +} > + > +static long sun4v_wdt_ioctl(struct file *file, unsigned int cmd, > + unsigned long arg) > +{ > + int new_options, retval = -EINVAL; > + int new_timeout; > + int __user *argp = (void __user *)arg; > + static const struct watchdog_info ident = { > + .options = WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE, > + .firmware_version = 0, > + .identity = "SUN4V Watchdog", > + }; > + > + 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, argp); > + > + case WDIOC_SETOPTIONS: > + if (get_user(new_options, argp)) > + return -EFAULT; > + > + if (new_options & WDIOS_DISABLECARD) > + retval = sun4v_wdt_stop(); > + if (new_options & WDIOS_ENABLECARD) { > + retval = sun4v_wdt_start(); > + if (retval == -EBUSY) > + retval = sun4v_wdt_kick(); > + } > + return retval; > + > + case WDIOC_KEEPALIVE: > + sun4v_wdt_kick(); > + return 0; > + > + case WDIOC_SETTIMEOUT: > + if (get_user(new_timeout, argp)) > + return -EFAULT; > + if (!new_timeout) > + return -EINVAL; > + timeout = new_timeout; > + sun4v_wdt_kick(); > + /* fall through */ > + case WDIOC_GETTIMEOUT: > + return put_user(timeout, argp); > + > + case WDIOC_GETTIMELEFT: > + retval = wdt_expires - ktime_to_timespec(ktime_get()).tv_sec; > + return put_user(retval, argp); > + } > + > + return -ENOTTY; > +} > + > +static const struct file_operations sun4v_wdt_fops = { > + .owner = THIS_MODULE, > + .llseek = no_llseek, > + .write = sun4v_wdt_write, > + .unlocked_ioctl = sun4v_wdt_ioctl, > + .open = sun4v_wdt_open, > + .release = sun4v_wdt_release, > +}; > + > +static struct miscdevice sun4v_wdt_miscdev = { > + .minor = WATCHDOG_MINOR, > + .name = "watchdog", > + .fops = &sun4v_wdt_fops, > +}; > + > +static int sun4v_wdt_probe(struct platform_device *dev) > +{ > + unsigned long wd_timeout = 0; > + unsigned long time_remaining; > + int ret; > + > + ret = sun4v_mach_set_watchdog(wd_timeout, &time_remaining); wd_timeout is 0 here and unused elsewhere in this function, so why not write this as: ret = sun4v_mach_set_watchdog(0, &time_remaining); and get rid of the variable? > + > + switch (ret) { > + case HV_EOK: > + if (!timeout) { > + timeout = WATCHDOG_TIMEOUT; > + pr_info("timeout value invalid, using %lu\n", timeout); > + } > + > + ret = misc_register(&sun4v_wdt_miscdev); > + if (ret) { > + pr_err("cannot register miscdev on minor=%d (%d)\n", > + WATCHDOG_MINOR, ret); > + break; > + } > + > + pr_info("initialized (timeout=%lus, nowayout=%d)\n", > + timeout, nowayout); > + break; > + > + case -ENOSYS: > + pr_info("not supported\n"); > + ret = -ENODEV; > + break; > + > + default: > + pr_info("bogus return value %d\n", ret); Does this also mean it's not supported? If so, should we be returning -ENODEV here too? > + break; > + } > + > + return ret; > +} > + > +static int sun4v_wdt_remove(struct platform_device *dev) > +{ > + /* Stop the timer before we leave */ Is this comment really needed? > + > + if (!nowayout) > + sun4v_wdt_stop(); Can this method even be called if nowayout is set as we've taken a reference to the module above? > + > + misc_deregister(&sun4v_wdt_miscdev); > + > + return 0; > +} > + > +static void sun4v_wdt_shutdown(struct platform_device *dev) > +{ > + sun4v_wdt_stop(); > +} > + > +static int sun4v_wdt_suspend(struct platform_device *dev, pm_message_t state) > +{ > + int ret = sun4v_wdt_stop(); > + return ret; Could this be written as: return sun4v_wdt_stop(); > +} > + > +static int sun4v_wdt_resume(struct platform_device *dev) > +{ > + return sun4v_wdt_start(); > +} > + > +static struct platform_driver sun4v_wdt_driver = { > + .probe = sun4v_wdt_probe, > + .remove = sun4v_wdt_remove, > + .shutdown = sun4v_wdt_shutdown, > + .suspend = sun4v_wdt_suspend, > + .resume = sun4v_wdt_resume, > + .driver = { > + .name = DRV_NAME, > + }, > +}; > + > +static int __init sun4v_wdt_init_module(void) > +{ > + int err; > + struct mdesc_handle *hp; > + u64 pn; > + const u64 *v; You could use more descriptive names here: "handle" instead of "hp", "node" instead of "pn" and "value" instead of "v". > + u64 max_timeout = 0; > + u64 resolution; > + > + /* > + * There are 2 properties that can be set from the control > + * domain for the watchdog. > + * watchdog-resolution (in ms defaulting to 1000) > + * watchdog-max-timeout (in ms) > + * Right now, only support the default 1s (1000ms) resolution > + * so just verify against the property, and make sure > + * max timeout is taken into account, if set. > + */ > + hp = mdesc_grab(); > + pn = mdesc_node_by_name(hp, MDESC_NODE_NULL, "platform"); > + > + if (pn == MDESC_NODE_NULL) { > + pr_info("No platform node \n"); > + return -ENODEV; > + } > + > + v = mdesc_get_property(hp, pn, "watchdog-resolution", NULL); > + if (v) { > + resolution = *v; > + pr_info("Platform watchdog-resolution [%llux]\n", *v); > + /* default resolution is 1000ms, should be fine */ > + /* not supporting anything else right now */ > + if (resolution != 1000) { > + pr_crit("Only 1000ms is supported.\n"); > + return -EINVAL; > + } > + } > + > + v = mdesc_get_property(hp, pn, "watchdog-max-timeout", NULL); > + if (v) { > + max_timeout = *v; max_timeout is only used in the function. Why not do the division here instead of below? I.e. max_timeout = *v / 1000; ... if (max_timeout < 1) { ... } if (timeout > max_timeout) { timeout = max_timeout; ... pr_info("Setting timeout to watchdog-max-timeout [%llu s]\n", max_timeout); } > + pr_info("Platform watchdog-max-timeout [%llu ms]\n", *v); > + if (max_timeout < 1000) { > + pr_crit("Timeout should be at least 1s(1000ms)\n"); > + return -EINVAL; > + } > + } What happens if we cannot get a maximum timeout value? max_timeout will be zero here, so the following if statement will set timeout to 0, which appears to be a magic value to disable the watchdog. It looks like either: 1. We should use a default max_timeout value. 2. We should fail. Continuing without doing either appears to break stuff. > + > + /* have to convert timeout in seconds to timeout in milliseconds */ > + if (timeout * 1000 > max_timeout) { > + /* and convert down to seconds again */ > + timeout = max_timeout / 1000; > + pr_info("Timeout larger than watchdog-max-timeout\n"); > + pr_info("Setting timeout to watchdog-max-timeout [%llu ms]\n", max_timeout); > + } > + > + pr_info("Sun4v WatchDog Timer Driver v%s\n", DRV_VERSION); > + > + err = platform_driver_register(&sun4v_wdt_driver); > + if (err) > + return err; > + > + platform_device = platform_device_register_simple(DRV_NAME, > + -1, NULL, 0); > + if (IS_ERR(platform_device)) { > + err = PTR_ERR(platform_device); > + platform_driver_unregister(&sun4v_wdt_driver); > + } > + > + return err; > +} > + > +static void __exit sun4v_wdt_cleanup_module(void) > +{ > + platform_device_unregister(platform_device); > + platform_driver_unregister(&sun4v_wdt_driver); > + pr_info("module unloaded\n"); > +} > + > +module_init(sun4v_wdt_init_module); > +module_exit(sun4v_wdt_cleanup_module); > + > +MODULE_AUTHOR("Wim Coekaerts <wim.coekaerts@oracle.com>"); > +MODULE_DESCRIPTION("Sun4v WatchDog Timer Driver"); > +MODULE_VERSION(DRV_VERSION); > +MODULE_LICENSE("GPL"); > -- > 1.7.1 > > -- > To unsubscribe from this list: send the line "unsubscribe sparclinux" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html
On Tue, Jan 12, 2016 at 03:10:32PM -0800, wim.coekaerts@oracle.com wrote: > From: Wim Coekaerts <wim.coekaerts@oracle.com> > > This adds a simple watchdog timer for the SPARC sunv4 architecture. > Export the sun4v_mach_set_watchdog() hv call, and add the target. > The driver was based on the same model used by the Xen watchdog driver. > > This was tested on T2, T4, T5 and T7. > > Signed-off-by: Wim Coekaerts <wim.coekaerts@oracle.com> Please use the watchdog subsystem for new drivers. Thanks, Guenter > --- > arch/sparc/kernel/sparc_ksyms_64.c | 1 + > drivers/watchdog/Kconfig | 10 + > drivers/watchdog/Makefile | 1 + > drivers/watchdog/sun4v_wdt.c | 421 ++++++++++++++++++++++++++++++++++++ > 4 files changed, 433 insertions(+), 0 deletions(-) > create mode 100644 drivers/watchdog/sun4v_wdt.c > > diff --git a/arch/sparc/kernel/sparc_ksyms_64.c b/arch/sparc/kernel/sparc_ksyms_64.c > index a92d5d2..9e034f2 100644 > --- a/arch/sparc/kernel/sparc_ksyms_64.c > +++ b/arch/sparc/kernel/sparc_ksyms_64.c > @@ -37,6 +37,7 @@ EXPORT_SYMBOL(sun4v_niagara_getperf); > EXPORT_SYMBOL(sun4v_niagara_setperf); > EXPORT_SYMBOL(sun4v_niagara2_getperf); > EXPORT_SYMBOL(sun4v_niagara2_setperf); > +EXPORT_SYMBOL(sun4v_mach_set_watchdog); > > /* from hweight.S */ > EXPORT_SYMBOL(__arch_hweight8); > diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig > index 1c427be..08834e4 100644 > --- a/drivers/watchdog/Kconfig > +++ b/drivers/watchdog/Kconfig > @@ -1516,6 +1516,16 @@ config UML_WATCHDOG > tristate "UML watchdog" > depends on UML > > +# SPARC sun4v > + > +config WATCHDOG_SUN4V > + tristate "Sun4v Watchdog support" > + depends on SPARC64 > + help > + Say Y here to support the hypervisor watchdog capability provided > + by the sun4v architecture. The watchdog timeout period is normally one > + minute but can be changed with a boot-time parameter. > + > # > # ISA-based Watchdog Cards > # > diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile > index 53d4827..9b8acb8 100644 > --- a/drivers/watchdog/Makefile > +++ b/drivers/watchdog/Makefile > @@ -175,6 +175,7 @@ obj-$(CONFIG_SH_WDT) += shwdt.o > > obj-$(CONFIG_WATCHDOG_RIO) += riowd.o > obj-$(CONFIG_WATCHDOG_CP1XXX) += cpwd.o > +obj-$(CONFIG_WATCHDOG_SUN4V) += sun4v_wdt.o > > # XTENSA Architecture > > diff --git a/drivers/watchdog/sun4v_wdt.c b/drivers/watchdog/sun4v_wdt.c > new file mode 100644 > index 0000000..1213a1f > --- /dev/null > +++ b/drivers/watchdog/sun4v_wdt.c > @@ -0,0 +1,421 @@ > +/* > + * Sun4v Watchdog Driver > + * (c) Copyright 2015 Oracle Corporation > + * > + * Heavily modified version of xen_wdt.c > + * (c) Copyright 2010 Novell, Inc. > + * > + * > + * 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. > + */ > + > +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt > + > +#define DRV_NAME "sun4v_wdt" > +#define DRV_VERSION "0.01" > + > +#include <linux/bug.h> > +#include <linux/errno.h> > +#include <linux/fs.h> > +#include <linux/hrtimer.h> > +#include <linux/kernel.h> > +#include <linux/ktime.h> > +#include <linux/init.h> > +#include <linux/miscdevice.h> > +#include <linux/module.h> > +#include <linux/moduleparam.h> > +#include <linux/platform_device.h> > +#include <linux/spinlock.h> > +#include <linux/uaccess.h> > +#include <linux/watchdog.h> > +#include <asm/hypervisor.h> > +#include <asm/mdesc.h> > + > + > +static struct platform_device *platform_device; > +static DEFINE_SPINLOCK(wdt_lock); > +static __kernel_time_t wdt_expires; > +static unsigned long is_active; > +static bool expect_release; > + > +unsigned long wdt_timeout = 0; > + > +#define WATCHDOG_TIMEOUT 60 /* in seconds */ > +static unsigned long timeout = WATCHDOG_TIMEOUT; > +module_param(timeout, ulong, S_IRUGO); > +MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds " > + "(default=" __MODULE_STRING(WATCHDOG_TIMEOUT) ")"); > + > +static bool nowayout = WATCHDOG_NOWAYOUT; > +module_param(nowayout, bool, S_IRUGO); > +MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started " > + "(default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); > + > +static inline __kernel_time_t set_timeout(void) > +{ > + /* > + * The hypervisor specifies WD timeout in milliseconds > + * Change it to seconds here and > + * to do it in one place rather than every call to > + * sun4v_mach_set_watchdog() > + * The hvcall expects milliseconds while the parameters > + * and the rest of the code expects seconds. wdt_timeout > + * is the variable that we pass to the hvcall. > + */ > + wdt_timeout = timeout * 1000; > + return ktime_to_timespec(ktime_get()).tv_sec + timeout; > +} > + > +static int sun4v_wdt_start(void) > +{ > + __kernel_time_t expires; > + unsigned long time_remaining; > + int err; > + > + spin_lock(&wdt_lock); > + > + expires = set_timeout(); > + err = sun4v_mach_set_watchdog(wdt_timeout, &time_remaining); > + > + spin_unlock(&wdt_lock); > + > + pr_info("Watchdog timer enabled\n"); > + return err; > +} > + > +static int sun4v_wdt_stop(void) > +{ > + int err; > + unsigned long time_remaining; > + > + spin_lock(&wdt_lock); > + > + err = sun4v_mach_set_watchdog(0, &time_remaining); > + > + spin_unlock(&wdt_lock); > + > + pr_info("Watchdog timer disabled\n"); > + return err; > +} > + > +static int sun4v_wdt_kick(void) > +{ > + __kernel_time_t expires; > + int err; > + unsigned long time_remaining; > + > + spin_lock(&wdt_lock); > + > + expires = set_timeout(); > + err = sun4v_mach_set_watchdog(wdt_timeout, &time_remaining); > + if (!err) > + wdt_expires = expires; > + > + spin_unlock(&wdt_lock); > + > + return err; > +} > + > +static int sun4v_wdt_open(struct inode *inode, struct file *file) > +{ > + int err; > + > + /* /dev/watchdog can only be opened once */ > + if (test_and_set_bit(0, &is_active)) > + return -EBUSY; > + > + /* prevent someone from rmmod'ing the module */ > + if (nowayout) > + __module_get(THIS_MODULE); > + > + err = sun4v_wdt_start(); > + if (err == -EBUSY) { > + err = sun4v_wdt_kick(); > + } > + > + return err ?: nonseekable_open(inode, file); > +} > + > +static int sun4v_wdt_release(struct inode *inode, struct file *file) > +{ > + int err; > + > + if (expect_release) > + err = sun4v_wdt_stop(); > + else { > + pr_crit("Unexpected close, not stopping watchdog!\n"); > + sun4v_wdt_kick(); > + } > + > + clear_bit(0, &is_active); > + expect_release = false; > + > + return 0; > +} > + > +static ssize_t sun4v_wdt_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; > + > + /* in case it was set long ago */ > + expect_release = false; > + > + /* 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') > + expect_release = true; > + } > + } > + > + /* someone wrote to us, we should reload the timer */ > + sun4v_wdt_kick(); > + } > + return len; > +} > + > +static long sun4v_wdt_ioctl(struct file *file, unsigned int cmd, > + unsigned long arg) > +{ > + int new_options, retval = -EINVAL; > + int new_timeout; > + int __user *argp = (void __user *)arg; > + static const struct watchdog_info ident = { > + .options = WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE, > + .firmware_version = 0, > + .identity = "SUN4V Watchdog", > + }; > + > + 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, argp); > + > + case WDIOC_SETOPTIONS: > + if (get_user(new_options, argp)) > + return -EFAULT; > + > + if (new_options & WDIOS_DISABLECARD) > + retval = sun4v_wdt_stop(); > + if (new_options & WDIOS_ENABLECARD) { > + retval = sun4v_wdt_start(); > + if (retval == -EBUSY) > + retval = sun4v_wdt_kick(); > + } > + return retval; > + > + case WDIOC_KEEPALIVE: > + sun4v_wdt_kick(); > + return 0; > + > + case WDIOC_SETTIMEOUT: > + if (get_user(new_timeout, argp)) > + return -EFAULT; > + if (!new_timeout) > + return -EINVAL; > + timeout = new_timeout; > + sun4v_wdt_kick(); > + /* fall through */ > + case WDIOC_GETTIMEOUT: > + return put_user(timeout, argp); > + > + case WDIOC_GETTIMELEFT: > + retval = wdt_expires - ktime_to_timespec(ktime_get()).tv_sec; > + return put_user(retval, argp); > + } > + > + return -ENOTTY; > +} > + > +static const struct file_operations sun4v_wdt_fops = { > + .owner = THIS_MODULE, > + .llseek = no_llseek, > + .write = sun4v_wdt_write, > + .unlocked_ioctl = sun4v_wdt_ioctl, > + .open = sun4v_wdt_open, > + .release = sun4v_wdt_release, > +}; > + > +static struct miscdevice sun4v_wdt_miscdev = { > + .minor = WATCHDOG_MINOR, > + .name = "watchdog", > + .fops = &sun4v_wdt_fops, > +}; > + > +static int sun4v_wdt_probe(struct platform_device *dev) > +{ > + unsigned long wd_timeout = 0; > + unsigned long time_remaining; > + int ret; > + > + ret = sun4v_mach_set_watchdog(wd_timeout, &time_remaining); > + > + switch (ret) { > + case HV_EOK: > + if (!timeout) { > + timeout = WATCHDOG_TIMEOUT; > + pr_info("timeout value invalid, using %lu\n", timeout); > + } > + > + ret = misc_register(&sun4v_wdt_miscdev); > + if (ret) { > + pr_err("cannot register miscdev on minor=%d (%d)\n", > + WATCHDOG_MINOR, ret); > + break; > + } > + > + pr_info("initialized (timeout=%lus, nowayout=%d)\n", > + timeout, nowayout); > + break; > + > + case -ENOSYS: > + pr_info("not supported\n"); > + ret = -ENODEV; > + break; > + > + default: > + pr_info("bogus return value %d\n", ret); > + break; > + } > + > + return ret; > +} > + > +static int sun4v_wdt_remove(struct platform_device *dev) > +{ > + /* Stop the timer before we leave */ > + > + if (!nowayout) > + sun4v_wdt_stop(); > + > + misc_deregister(&sun4v_wdt_miscdev); > + > + return 0; > +} > + > +static void sun4v_wdt_shutdown(struct platform_device *dev) > +{ > + sun4v_wdt_stop(); > +} > + > +static int sun4v_wdt_suspend(struct platform_device *dev, pm_message_t state) > +{ > + int ret = sun4v_wdt_stop(); > + return ret; > +} > + > +static int sun4v_wdt_resume(struct platform_device *dev) > +{ > + return sun4v_wdt_start(); > +} > + > +static struct platform_driver sun4v_wdt_driver = { > + .probe = sun4v_wdt_probe, > + .remove = sun4v_wdt_remove, > + .shutdown = sun4v_wdt_shutdown, > + .suspend = sun4v_wdt_suspend, > + .resume = sun4v_wdt_resume, > + .driver = { > + .name = DRV_NAME, > + }, > +}; > + > +static int __init sun4v_wdt_init_module(void) > +{ > + int err; > + struct mdesc_handle *hp; > + u64 pn; > + const u64 *v; > + u64 max_timeout = 0; > + u64 resolution; > + > + /* > + * There are 2 properties that can be set from the control > + * domain for the watchdog. > + * watchdog-resolution (in ms defaulting to 1000) > + * watchdog-max-timeout (in ms) > + * Right now, only support the default 1s (1000ms) resolution > + * so just verify against the property, and make sure > + * max timeout is taken into account, if set. > + */ > + hp = mdesc_grab(); > + pn = mdesc_node_by_name(hp, MDESC_NODE_NULL, "platform"); > + > + if (pn == MDESC_NODE_NULL) { > + pr_info("No platform node \n"); > + return -ENODEV; > + } > + > + v = mdesc_get_property(hp, pn, "watchdog-resolution", NULL); > + if (v) { > + resolution = *v; > + pr_info("Platform watchdog-resolution [%llux]\n", *v); > + /* default resolution is 1000ms, should be fine */ > + /* not supporting anything else right now */ > + if (resolution != 1000) { > + pr_crit("Only 1000ms is supported.\n"); > + return -EINVAL; > + } > + } > + > + v = mdesc_get_property(hp, pn, "watchdog-max-timeout", NULL); > + if (v) { > + max_timeout = *v; > + pr_info("Platform watchdog-max-timeout [%llu ms]\n", *v); > + if (max_timeout < 1000) { > + pr_crit("Timeout should be at least 1s(1000ms)\n"); > + return -EINVAL; > + } > + } > + > + /* have to convert timeout in seconds to timeout in milliseconds */ > + if (timeout * 1000 > max_timeout) { > + /* and convert down to seconds again */ > + timeout = max_timeout / 1000; > + pr_info("Timeout larger than watchdog-max-timeout\n"); > + pr_info("Setting timeout to watchdog-max-timeout [%llu ms]\n", max_timeout); > + } > + > + pr_info("Sun4v WatchDog Timer Driver v%s\n", DRV_VERSION); > + > + err = platform_driver_register(&sun4v_wdt_driver); > + if (err) > + return err; > + > + platform_device = platform_device_register_simple(DRV_NAME, > + -1, NULL, 0); > + if (IS_ERR(platform_device)) { > + err = PTR_ERR(platform_device); > + platform_driver_unregister(&sun4v_wdt_driver); > + } > + > + return err; > +} > + > +static void __exit sun4v_wdt_cleanup_module(void) > +{ > + platform_device_unregister(platform_device); > + platform_driver_unregister(&sun4v_wdt_driver); > + pr_info("module unloaded\n"); > +} > + > +module_init(sun4v_wdt_init_module); > +module_exit(sun4v_wdt_cleanup_module); > + > +MODULE_AUTHOR("Wim Coekaerts <wim.coekaerts@oracle.com>"); > +MODULE_DESCRIPTION("Sun4v WatchDog Timer Driver"); > +MODULE_VERSION(DRV_VERSION); > +MODULE_LICENSE("GPL"); > -- > 1.7.1 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-watchdog" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe sparclinux" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 1/12/16 5:12 PM, Guenter Roeck wrote: > On Tue, Jan 12, 2016 at 03:10:32PM -0800, wim.coekaerts@oracle.com wrote: >> From: Wim Coekaerts <wim.coekaerts@oracle.com> >> >> This adds a simple watchdog timer for the SPARC sunv4 architecture. >> Export the sun4v_mach_set_watchdog() hv call, and add the target. >> The driver was based on the same model used by the Xen watchdog driver. >> >> This was tested on T2, T4, T5 and T7. >> >> Signed-off-by: Wim Coekaerts <wim.coekaerts@oracle.com> > Please use the watchdog subsystem for new drivers. Ah wasn't clear that that was a requirement.. OK let me try and use the new subsystem instead. -- To unsubscribe from this list: send the line "unsubscribe sparclinux" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
From: wim.coekaerts@oracle.com Date: Tue, 12 Jan 2016 15:10:32 -0800 > +static int sun4v_wdt_stop(void) > +{ > + int err; > + unsigned long time_remaining; > + > + spin_lock(&wdt_lock); > + > + err = sun4v_mach_set_watchdog(0, &time_remaining); There's a lot of lines like this last one which use spaces, instead of TAB characters. Please fix this up during your conversion to the watchdog subsystem. > + err = sun4v_wdt_start(); > + if (err == -EBUSY) { > + err = sun4v_wdt_kick(); > + } Single line basic blocks do not get curly braces. > + hp = mdesc_grab(); I don't see any mdesc_put() to release the machine description. -- To unsubscribe from this list: send the line "unsubscribe sparclinux" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/arch/sparc/kernel/sparc_ksyms_64.c b/arch/sparc/kernel/sparc_ksyms_64.c index a92d5d2..9e034f2 100644 --- a/arch/sparc/kernel/sparc_ksyms_64.c +++ b/arch/sparc/kernel/sparc_ksyms_64.c @@ -37,6 +37,7 @@ EXPORT_SYMBOL(sun4v_niagara_getperf); EXPORT_SYMBOL(sun4v_niagara_setperf); EXPORT_SYMBOL(sun4v_niagara2_getperf); EXPORT_SYMBOL(sun4v_niagara2_setperf); +EXPORT_SYMBOL(sun4v_mach_set_watchdog); /* from hweight.S */ EXPORT_SYMBOL(__arch_hweight8); diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig index 1c427be..08834e4 100644 --- a/drivers/watchdog/Kconfig +++ b/drivers/watchdog/Kconfig @@ -1516,6 +1516,16 @@ config UML_WATCHDOG tristate "UML watchdog" depends on UML +# SPARC sun4v + +config WATCHDOG_SUN4V + tristate "Sun4v Watchdog support" + depends on SPARC64 + help + Say Y here to support the hypervisor watchdog capability provided + by the sun4v architecture. The watchdog timeout period is normally one + minute but can be changed with a boot-time parameter. + # # ISA-based Watchdog Cards # diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile index 53d4827..9b8acb8 100644 --- a/drivers/watchdog/Makefile +++ b/drivers/watchdog/Makefile @@ -175,6 +175,7 @@ obj-$(CONFIG_SH_WDT) += shwdt.o obj-$(CONFIG_WATCHDOG_RIO) += riowd.o obj-$(CONFIG_WATCHDOG_CP1XXX) += cpwd.o +obj-$(CONFIG_WATCHDOG_SUN4V) += sun4v_wdt.o # XTENSA Architecture diff --git a/drivers/watchdog/sun4v_wdt.c b/drivers/watchdog/sun4v_wdt.c new file mode 100644 index 0000000..1213a1f --- /dev/null +++ b/drivers/watchdog/sun4v_wdt.c @@ -0,0 +1,421 @@ +/* + * Sun4v Watchdog Driver + * (c) Copyright 2015 Oracle Corporation + * + * Heavily modified version of xen_wdt.c + * (c) Copyright 2010 Novell, Inc. + * + * + * 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. + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#define DRV_NAME "sun4v_wdt" +#define DRV_VERSION "0.01" + +#include <linux/bug.h> +#include <linux/errno.h> +#include <linux/fs.h> +#include <linux/hrtimer.h> +#include <linux/kernel.h> +#include <linux/ktime.h> +#include <linux/init.h> +#include <linux/miscdevice.h> +#include <linux/module.h> +#include <linux/moduleparam.h> +#include <linux/platform_device.h> +#include <linux/spinlock.h> +#include <linux/uaccess.h> +#include <linux/watchdog.h> +#include <asm/hypervisor.h> +#include <asm/mdesc.h> + + +static struct platform_device *platform_device; +static DEFINE_SPINLOCK(wdt_lock); +static __kernel_time_t wdt_expires; +static unsigned long is_active; +static bool expect_release; + +unsigned long wdt_timeout = 0; + +#define WATCHDOG_TIMEOUT 60 /* in seconds */ +static unsigned long timeout = WATCHDOG_TIMEOUT; +module_param(timeout, ulong, S_IRUGO); +MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds " + "(default=" __MODULE_STRING(WATCHDOG_TIMEOUT) ")"); + +static bool nowayout = WATCHDOG_NOWAYOUT; +module_param(nowayout, bool, S_IRUGO); +MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started " + "(default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); + +static inline __kernel_time_t set_timeout(void) +{ + /* + * The hypervisor specifies WD timeout in milliseconds + * Change it to seconds here and + * to do it in one place rather than every call to + * sun4v_mach_set_watchdog() + * The hvcall expects milliseconds while the parameters + * and the rest of the code expects seconds. wdt_timeout + * is the variable that we pass to the hvcall. + */ + wdt_timeout = timeout * 1000; + return ktime_to_timespec(ktime_get()).tv_sec + timeout; +} + +static int sun4v_wdt_start(void) +{ + __kernel_time_t expires; + unsigned long time_remaining; + int err; + + spin_lock(&wdt_lock); + + expires = set_timeout(); + err = sun4v_mach_set_watchdog(wdt_timeout, &time_remaining); + + spin_unlock(&wdt_lock); + + pr_info("Watchdog timer enabled\n"); + return err; +} + +static int sun4v_wdt_stop(void) +{ + int err; + unsigned long time_remaining; + + spin_lock(&wdt_lock); + + err = sun4v_mach_set_watchdog(0, &time_remaining); + + spin_unlock(&wdt_lock); + + pr_info("Watchdog timer disabled\n"); + return err; +} + +static int sun4v_wdt_kick(void) +{ + __kernel_time_t expires; + int err; + unsigned long time_remaining; + + spin_lock(&wdt_lock); + + expires = set_timeout(); + err = sun4v_mach_set_watchdog(wdt_timeout, &time_remaining); + if (!err) + wdt_expires = expires; + + spin_unlock(&wdt_lock); + + return err; +} + +static int sun4v_wdt_open(struct inode *inode, struct file *file) +{ + int err; + + /* /dev/watchdog can only be opened once */ + if (test_and_set_bit(0, &is_active)) + return -EBUSY; + + /* prevent someone from rmmod'ing the module */ + if (nowayout) + __module_get(THIS_MODULE); + + err = sun4v_wdt_start(); + if (err == -EBUSY) { + err = sun4v_wdt_kick(); + } + + return err ?: nonseekable_open(inode, file); +} + +static int sun4v_wdt_release(struct inode *inode, struct file *file) +{ + int err; + + if (expect_release) + err = sun4v_wdt_stop(); + else { + pr_crit("Unexpected close, not stopping watchdog!\n"); + sun4v_wdt_kick(); + } + + clear_bit(0, &is_active); + expect_release = false; + + return 0; +} + +static ssize_t sun4v_wdt_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; + + /* in case it was set long ago */ + expect_release = false; + + /* 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') + expect_release = true; + } + } + + /* someone wrote to us, we should reload the timer */ + sun4v_wdt_kick(); + } + return len; +} + +static long sun4v_wdt_ioctl(struct file *file, unsigned int cmd, + unsigned long arg) +{ + int new_options, retval = -EINVAL; + int new_timeout; + int __user *argp = (void __user *)arg; + static const struct watchdog_info ident = { + .options = WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE, + .firmware_version = 0, + .identity = "SUN4V Watchdog", + }; + + 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, argp); + + case WDIOC_SETOPTIONS: + if (get_user(new_options, argp)) + return -EFAULT; + + if (new_options & WDIOS_DISABLECARD) + retval = sun4v_wdt_stop(); + if (new_options & WDIOS_ENABLECARD) { + retval = sun4v_wdt_start(); + if (retval == -EBUSY) + retval = sun4v_wdt_kick(); + } + return retval; + + case WDIOC_KEEPALIVE: + sun4v_wdt_kick(); + return 0; + + case WDIOC_SETTIMEOUT: + if (get_user(new_timeout, argp)) + return -EFAULT; + if (!new_timeout) + return -EINVAL; + timeout = new_timeout; + sun4v_wdt_kick(); + /* fall through */ + case WDIOC_GETTIMEOUT: + return put_user(timeout, argp); + + case WDIOC_GETTIMELEFT: + retval = wdt_expires - ktime_to_timespec(ktime_get()).tv_sec; + return put_user(retval, argp); + } + + return -ENOTTY; +} + +static const struct file_operations sun4v_wdt_fops = { + .owner = THIS_MODULE, + .llseek = no_llseek, + .write = sun4v_wdt_write, + .unlocked_ioctl = sun4v_wdt_ioctl, + .open = sun4v_wdt_open, + .release = sun4v_wdt_release, +}; + +static struct miscdevice sun4v_wdt_miscdev = { + .minor = WATCHDOG_MINOR, + .name = "watchdog", + .fops = &sun4v_wdt_fops, +}; + +static int sun4v_wdt_probe(struct platform_device *dev) +{ + unsigned long wd_timeout = 0; + unsigned long time_remaining; + int ret; + + ret = sun4v_mach_set_watchdog(wd_timeout, &time_remaining); + + switch (ret) { + case HV_EOK: + if (!timeout) { + timeout = WATCHDOG_TIMEOUT; + pr_info("timeout value invalid, using %lu\n", timeout); + } + + ret = misc_register(&sun4v_wdt_miscdev); + if (ret) { + pr_err("cannot register miscdev on minor=%d (%d)\n", + WATCHDOG_MINOR, ret); + break; + } + + pr_info("initialized (timeout=%lus, nowayout=%d)\n", + timeout, nowayout); + break; + + case -ENOSYS: + pr_info("not supported\n"); + ret = -ENODEV; + break; + + default: + pr_info("bogus return value %d\n", ret); + break; + } + + return ret; +} + +static int sun4v_wdt_remove(struct platform_device *dev) +{ + /* Stop the timer before we leave */ + + if (!nowayout) + sun4v_wdt_stop(); + + misc_deregister(&sun4v_wdt_miscdev); + + return 0; +} + +static void sun4v_wdt_shutdown(struct platform_device *dev) +{ + sun4v_wdt_stop(); +} + +static int sun4v_wdt_suspend(struct platform_device *dev, pm_message_t state) +{ + int ret = sun4v_wdt_stop(); + return ret; +} + +static int sun4v_wdt_resume(struct platform_device *dev) +{ + return sun4v_wdt_start(); +} + +static struct platform_driver sun4v_wdt_driver = { + .probe = sun4v_wdt_probe, + .remove = sun4v_wdt_remove, + .shutdown = sun4v_wdt_shutdown, + .suspend = sun4v_wdt_suspend, + .resume = sun4v_wdt_resume, + .driver = { + .name = DRV_NAME, + }, +}; + +static int __init sun4v_wdt_init_module(void) +{ + int err; + struct mdesc_handle *hp; + u64 pn; + const u64 *v; + u64 max_timeout = 0; + u64 resolution; + + /* + * There are 2 properties that can be set from the control + * domain for the watchdog. + * watchdog-resolution (in ms defaulting to 1000) + * watchdog-max-timeout (in ms) + * Right now, only support the default 1s (1000ms) resolution + * so just verify against the property, and make sure + * max timeout is taken into account, if set. + */ + hp = mdesc_grab(); + pn = mdesc_node_by_name(hp, MDESC_NODE_NULL, "platform"); + + if (pn == MDESC_NODE_NULL) { + pr_info("No platform node \n"); + return -ENODEV; + } + + v = mdesc_get_property(hp, pn, "watchdog-resolution", NULL); + if (v) { + resolution = *v; + pr_info("Platform watchdog-resolution [%llux]\n", *v); + /* default resolution is 1000ms, should be fine */ + /* not supporting anything else right now */ + if (resolution != 1000) { + pr_crit("Only 1000ms is supported.\n"); + return -EINVAL; + } + } + + v = mdesc_get_property(hp, pn, "watchdog-max-timeout", NULL); + if (v) { + max_timeout = *v; + pr_info("Platform watchdog-max-timeout [%llu ms]\n", *v); + if (max_timeout < 1000) { + pr_crit("Timeout should be at least 1s(1000ms)\n"); + return -EINVAL; + } + } + + /* have to convert timeout in seconds to timeout in milliseconds */ + if (timeout * 1000 > max_timeout) { + /* and convert down to seconds again */ + timeout = max_timeout / 1000; + pr_info("Timeout larger than watchdog-max-timeout\n"); + pr_info("Setting timeout to watchdog-max-timeout [%llu ms]\n", max_timeout); + } + + pr_info("Sun4v WatchDog Timer Driver v%s\n", DRV_VERSION); + + err = platform_driver_register(&sun4v_wdt_driver); + if (err) + return err; + + platform_device = platform_device_register_simple(DRV_NAME, + -1, NULL, 0); + if (IS_ERR(platform_device)) { + err = PTR_ERR(platform_device); + platform_driver_unregister(&sun4v_wdt_driver); + } + + return err; +} + +static void __exit sun4v_wdt_cleanup_module(void) +{ + platform_device_unregister(platform_device); + platform_driver_unregister(&sun4v_wdt_driver); + pr_info("module unloaded\n"); +} + +module_init(sun4v_wdt_init_module); +module_exit(sun4v_wdt_cleanup_module); + +MODULE_AUTHOR("Wim Coekaerts <wim.coekaerts@oracle.com>"); +MODULE_DESCRIPTION("Sun4v WatchDog Timer Driver"); +MODULE_VERSION(DRV_VERSION); +MODULE_LICENSE("GPL");