From 75722d3992f57375c0cc029dcceb2334a45ceff1 Mon Sep 17 00:00:00 2001 From: Benjamin Herrenschmidt Date: Mon, 7 Nov 2005 16:08:17 +1100 Subject: [PATCH] ppc64: Thermal control for SMU based machines This adds a new thermal control framework for PowerMac, along with the implementation for PowerMac8,1, PowerMac8,2 (iMac G5 rev 1 and 2), and PowerMac9,1 (latest single CPU desktop). In the future, I expect to move the older G5 thermal control to the new framework as well. Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Paul Mackerras --- drivers/macintosh/windfarm_core.c | 426 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 426 insertions(+) create mode 100644 drivers/macintosh/windfarm_core.c (limited to 'drivers/macintosh/windfarm_core.c') diff --git a/drivers/macintosh/windfarm_core.c b/drivers/macintosh/windfarm_core.c new file mode 100644 index 00000000000..6c2a471ea6c --- /dev/null +++ b/drivers/macintosh/windfarm_core.c @@ -0,0 +1,426 @@ +/* + * Windfarm PowerMac thermal control. Core + * + * (c) Copyright 2005 Benjamin Herrenschmidt, IBM Corp. + * + * + * Released under the term of the GNU GPL v2. + * + * This core code tracks the list of sensors & controls, register + * clients, and holds the kernel thread used for control. + * + * TODO: + * + * Add some information about sensor/control type and data format to + * sensors/controls, and have the sysfs attribute stuff be moved + * generically here instead of hard coded in the platform specific + * driver as it us currently + * + * This however requires solving some annoying lifetime issues with + * sysfs which doesn't seem to have lifetime rules for struct attribute, + * I may have to create full features kobjects for every sensor/control + * instead which is a bit of an overkill imho + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "windfarm.h" + +#define VERSION "0.2" + +#undef DEBUG + +#ifdef DEBUG +#define DBG(args...) printk(args) +#else +#define DBG(args...) do { } while(0) +#endif + +static LIST_HEAD(wf_controls); +static LIST_HEAD(wf_sensors); +static DECLARE_MUTEX(wf_lock); +static struct notifier_block *wf_client_list; +static int wf_client_count; +static unsigned int wf_overtemp; +static unsigned int wf_overtemp_counter; +struct task_struct *wf_thread; + +/* + * Utilities & tick thread + */ + +static inline void wf_notify(int event, void *param) +{ + notifier_call_chain(&wf_client_list, event, param); +} + +int wf_critical_overtemp(void) +{ + static char * critical_overtemp_path = "/sbin/critical_overtemp"; + char *argv[] = { critical_overtemp_path, NULL }; + static char *envp[] = { "HOME=/", + "TERM=linux", + "PATH=/sbin:/usr/sbin:/bin:/usr/bin", + NULL }; + + return call_usermodehelper(critical_overtemp_path, argv, envp, 0); +} +EXPORT_SYMBOL_GPL(wf_critical_overtemp); + +static int wf_thread_func(void *data) +{ + unsigned long next, delay; + + next = jiffies; + + DBG("wf: thread started\n"); + + while(!kthread_should_stop()) { + try_to_freeze(); + + if (time_after_eq(jiffies, next)) { + wf_notify(WF_EVENT_TICK, NULL); + if (wf_overtemp) { + wf_overtemp_counter++; + /* 10 seconds overtemp, notify userland */ + if (wf_overtemp_counter > 10) + wf_critical_overtemp(); + /* 30 seconds, shutdown */ + if (wf_overtemp_counter > 30) { + printk(KERN_ERR "windfarm: Overtemp " + "for more than 30" + " seconds, shutting down\n"); + machine_power_off(); + } + } + next += HZ; + } + + delay = next - jiffies; + if (delay <= HZ) + schedule_timeout_interruptible(delay); + + /* there should be no signal, but oh well */ + if (signal_pending(current)) { + printk(KERN_WARNING "windfarm: thread got sigl !\n"); + break; + } + } + + DBG("wf: thread stopped\n"); + + return 0; +} + +static void wf_start_thread(void) +{ + wf_thread = kthread_run(wf_thread_func, NULL, "kwindfarm"); + if (IS_ERR(wf_thread)) { + printk(KERN_ERR "windfarm: failed to create thread,err %ld\n", + PTR_ERR(wf_thread)); + wf_thread = NULL; + } +} + + +static void wf_stop_thread(void) +{ + if (wf_thread) + kthread_stop(wf_thread); + wf_thread = NULL; +} + +/* + * Controls + */ + +static void wf_control_release(struct kref *kref) +{ + struct wf_control *ct = container_of(kref, struct wf_control, ref); + + DBG("wf: Deleting control %s\n", ct->name); + + if (ct->ops && ct->ops->release) + ct->ops->release(ct); + else + kfree(ct); +} + +int wf_register_control(struct wf_control *new_ct) +{ + struct wf_control *ct; + + down(&wf_lock); + list_for_each_entry(ct, &wf_controls, link) { + if (!strcmp(ct->name, new_ct->name)) { + printk(KERN_WARNING "windfarm: trying to register" + " duplicate control %s\n", ct->name); + up(&wf_lock); + return -EEXIST; + } + } + kref_init(&new_ct->ref); + list_add(&new_ct->link, &wf_controls); + + DBG("wf: Registered control %s\n", new_ct->name); + + wf_notify(WF_EVENT_NEW_CONTROL, new_ct); + up(&wf_lock); + + return 0; +} +EXPORT_SYMBOL_GPL(wf_register_control); + +void wf_unregister_control(struct wf_control *ct) +{ + down(&wf_lock); + list_del(&ct->link); + up(&wf_lock); + + DBG("wf: Unregistered control %s\n", ct->name); + + kref_put(&ct->ref, wf_control_release); +} +EXPORT_SYMBOL_GPL(wf_unregister_control); + +struct wf_control * wf_find_control(const char *name) +{ + struct wf_control *ct; + + down(&wf_lock); + list_for_each_entry(ct, &wf_controls, link) { + if (!strcmp(ct->name, name)) { + if (wf_get_control(ct)) + ct = NULL; + up(&wf_lock); + return ct; + } + } + up(&wf_lock); + return NULL; +} +EXPORT_SYMBOL_GPL(wf_find_control); + +int wf_get_control(struct wf_control *ct) +{ + if (!try_module_get(ct->ops->owner)) + return -ENODEV; + kref_get(&ct->ref); + return 0; +} +EXPORT_SYMBOL_GPL(wf_get_control); + +void wf_put_control(struct wf_control *ct) +{ + struct module *mod = ct->ops->owner; + kref_put(&ct->ref, wf_control_release); + module_put(mod); +} +EXPORT_SYMBOL_GPL(wf_put_control); + + +/* + * Sensors + */ + + +static void wf_sensor_release(struct kref *kref) +{ + struct wf_sensor *sr = container_of(kref, struct wf_sensor, ref); + + DBG("wf: Deleting sensor %s\n", sr->name); + + if (sr->ops && sr->ops->release) + sr->ops->release(sr); + else + kfree(sr); +} + +int wf_register_sensor(struct wf_sensor *new_sr) +{ + struct wf_sensor *sr; + + down(&wf_lock); + list_for_each_entry(sr, &wf_sensors, link) { + if (!strcmp(sr->name, new_sr->name)) { + printk(KERN_WARNING "windfarm: trying to register" + " duplicate sensor %s\n", sr->name); + up(&wf_lock); + return -EEXIST; + } + } + kref_init(&new_sr->ref); + list_add(&new_sr->link, &wf_sensors); + + DBG("wf: Registered sensor %s\n", new_sr->name); + + wf_notify(WF_EVENT_NEW_SENSOR, new_sr); + up(&wf_lock); + + return 0; +} +EXPORT_SYMBOL_GPL(wf_register_sensor); + +void wf_unregister_sensor(struct wf_sensor *sr) +{ + down(&wf_lock); + list_del(&sr->link); + up(&wf_lock); + + DBG("wf: Unregistered sensor %s\n", sr->name); + + wf_put_sensor(sr); +} +EXPORT_SYMBOL_GPL(wf_unregister_sensor); + +struct wf_sensor * wf_find_sensor(const char *name) +{ + struct wf_sensor *sr; + + down(&wf_lock); + list_for_each_entry(sr, &wf_sensors, link) { + if (!strcmp(sr->name, name)) { + if (wf_get_sensor(sr)) + sr = NULL; + up(&wf_lock); + return sr; + } + } + up(&wf_lock); + return NULL; +} +EXPORT_SYMBOL_GPL(wf_find_sensor); + +int wf_get_sensor(struct wf_sensor *sr) +{ + if (!try_module_get(sr->ops->owner)) + return -ENODEV; + kref_get(&sr->ref); + return 0; +} +EXPORT_SYMBOL_GPL(wf_get_sensor); + +void wf_put_sensor(struct wf_sensor *sr) +{ + struct module *mod = sr->ops->owner; + kref_put(&sr->ref, wf_sensor_release); + module_put(mod); +} +EXPORT_SYMBOL_GPL(wf_put_sensor); + + +/* + * Client & notification + */ + +int wf_register_client(struct notifier_block *nb) +{ + int rc; + struct wf_control *ct; + struct wf_sensor *sr; + + down(&wf_lock); + rc = notifier_chain_register(&wf_client_list, nb); + if (rc != 0) + goto bail; + wf_client_count++; + list_for_each_entry(ct, &wf_controls, link) + wf_notify(WF_EVENT_NEW_CONTROL, ct); + list_for_each_entry(sr, &wf_sensors, link) + wf_notify(WF_EVENT_NEW_SENSOR, sr); + if (wf_client_count == 1) + wf_start_thread(); + bail: + up(&wf_lock); + return rc; +} +EXPORT_SYMBOL_GPL(wf_register_client); + +int wf_unregister_client(struct notifier_block *nb) +{ + down(&wf_lock); + notifier_chain_unregister(&wf_client_list, nb); + wf_client_count++; + if (wf_client_count == 0) + wf_stop_thread(); + up(&wf_lock); + + return 0; +} +EXPORT_SYMBOL_GPL(wf_unregister_client); + +void wf_set_overtemp(void) +{ + down(&wf_lock); + wf_overtemp++; + if (wf_overtemp == 1) { + printk(KERN_WARNING "windfarm: Overtemp condition detected !\n"); + wf_overtemp_counter = 0; + wf_notify(WF_EVENT_OVERTEMP, NULL); + } + up(&wf_lock); +} +EXPORT_SYMBOL_GPL(wf_set_overtemp); + +void wf_clear_overtemp(void) +{ + down(&wf_lock); + WARN_ON(wf_overtemp == 0); + if (wf_overtemp == 0) { + up(&wf_lock); + return; + } + wf_overtemp--; + if (wf_overtemp == 0) { + printk(KERN_WARNING "windfarm: Overtemp condition cleared !\n"); + wf_notify(WF_EVENT_NORMALTEMP, NULL); + } + up(&wf_lock); +} +EXPORT_SYMBOL_GPL(wf_clear_overtemp); + +int wf_is_overtemp(void) +{ + return (wf_overtemp != 0); +} +EXPORT_SYMBOL_GPL(wf_is_overtemp); + +static struct platform_device wf_platform_device = { + .name = "windfarm", +}; + +static int __init windfarm_core_init(void) +{ + DBG("wf: core loaded\n"); + + platform_device_register(&wf_platform_device); + return 0; +} + +static void __exit windfarm_core_exit(void) +{ + BUG_ON(wf_client_count != 0); + + DBG("wf: core unloaded\n"); + + platform_device_unregister(&wf_platform_device); +} + + +module_init(windfarm_core_init); +module_exit(windfarm_core_exit); + +MODULE_AUTHOR("Benjamin Herrenschmidt "); +MODULE_DESCRIPTION("Core component of PowerMac thermal control"); +MODULE_LICENSE("GPL"); + -- cgit v1.2.3