x86, mce: squash mce_intel.c into therm_throt.c
[linux-2.6.git] / arch / x86 / kernel / cpu / mcheck / therm_throt.c
1 /*
2  * Thermal throttle event support code (such as syslog messaging and rate
3  * limiting) that was factored out from x86_64 (mce_intel.c) and i386 (p4.c).
4  *
5  * This allows consistent reporting of CPU thermal throttle events.
6  *
7  * Maintains a counter in /sys that keeps track of the number of thermal
8  * events, such that the user knows how bad the thermal problem might be
9  * (since the logging to syslog and mcelog is rate limited).
10  *
11  * Author: Dmitriy Zavin (dmitriyz@google.com)
12  *
13  * Credits: Adapted from Zwane Mwaikambo's original code in mce_intel.c.
14  *          Inspired by Ross Biro's and Al Borchers' counter code.
15  */
16 #include <linux/interrupt.h>
17 #include <linux/notifier.h>
18 #include <linux/jiffies.h>
19 #include <linux/kernel.h>
20 #include <linux/percpu.h>
21 #include <linux/sysdev.h>
22 #include <linux/types.h>
23 #include <linux/init.h>
24 #include <linux/smp.h>
25 #include <linux/cpu.h>
26
27 #include <asm/therm_throt.h>
28 #include <asm/processor.h>
29 #include <asm/system.h>
30 #include <asm/apic.h>
31 #include <asm/idle.h>
32 #include <asm/mce.h>
33 #include <asm/msr.h>
34
35 /* How long to wait between reporting thermal events */
36 #define CHECK_INTERVAL          (300 * HZ)
37
38 static DEFINE_PER_CPU(__u64, next_check) = INITIAL_JIFFIES;
39 static DEFINE_PER_CPU(unsigned long, thermal_throttle_count);
40
41 atomic_t therm_throt_en         = ATOMIC_INIT(0);
42
43 #ifdef CONFIG_SYSFS
44 #define define_therm_throt_sysdev_one_ro(_name)                         \
45         static SYSDEV_ATTR(_name, 0444, therm_throt_sysdev_show_##_name, NULL)
46
47 #define define_therm_throt_sysdev_show_func(name)                       \
48 static ssize_t therm_throt_sysdev_show_##name(struct sys_device *dev,   \
49                                         struct sysdev_attribute *attr,  \
50                                               char *buf)                \
51 {                                                                       \
52         unsigned int cpu = dev->id;                                     \
53         ssize_t ret;                                                    \
54                                                                         \
55         preempt_disable();      /* CPU hotplug */                       \
56         if (cpu_online(cpu))                                            \
57                 ret = sprintf(buf, "%lu\n",                             \
58                               per_cpu(thermal_throttle_##name, cpu));   \
59         else                                                            \
60                 ret = 0;                                                \
61         preempt_enable();                                               \
62                                                                         \
63         return ret;                                                     \
64 }
65
66 define_therm_throt_sysdev_show_func(count);
67 define_therm_throt_sysdev_one_ro(count);
68
69 static struct attribute *thermal_throttle_attrs[] = {
70         &attr_count.attr,
71         NULL
72 };
73
74 static struct attribute_group thermal_throttle_attr_group = {
75         .attrs  = thermal_throttle_attrs,
76         .name   = "thermal_throttle"
77 };
78 #endif /* CONFIG_SYSFS */
79
80 /***
81  * therm_throt_process - Process thermal throttling event from interrupt
82  * @curr: Whether the condition is current or not (boolean), since the
83  *        thermal interrupt normally gets called both when the thermal
84  *        event begins and once the event has ended.
85  *
86  * This function is called by the thermal interrupt after the
87  * IRQ has been acknowledged.
88  *
89  * It will take care of rate limiting and printing messages to the syslog.
90  *
91  * Returns: 0 : Event should NOT be further logged, i.e. still in
92  *              "timeout" from previous log message.
93  *          1 : Event should be logged further, and a message has been
94  *              printed to the syslog.
95  */
96 int therm_throt_process(int curr)
97 {
98         unsigned int cpu = smp_processor_id();
99         __u64 tmp_jiffs = get_jiffies_64();
100
101         if (curr)
102                 __get_cpu_var(thermal_throttle_count)++;
103
104         if (time_before64(tmp_jiffs, __get_cpu_var(next_check)))
105                 return 0;
106
107         __get_cpu_var(next_check) = tmp_jiffs + CHECK_INTERVAL;
108
109         /* if we just entered the thermal event */
110         if (curr) {
111                 printk(KERN_CRIT "CPU%d: Temperature above threshold, "
112                        "cpu clock throttled (total events = %lu)\n", cpu,
113                        __get_cpu_var(thermal_throttle_count));
114
115                 add_taint(TAINT_MACHINE_CHECK);
116         } else {
117                 printk(KERN_CRIT "CPU%d: Temperature/speed normal\n", cpu);
118         }
119
120         return 1;
121 }
122
123 #ifdef CONFIG_SYSFS
124 /* Add/Remove thermal_throttle interface for CPU device: */
125 static __cpuinit int thermal_throttle_add_dev(struct sys_device *sys_dev)
126 {
127         return sysfs_create_group(&sys_dev->kobj,
128                                   &thermal_throttle_attr_group);
129 }
130
131 static __cpuinit void thermal_throttle_remove_dev(struct sys_device *sys_dev)
132 {
133         sysfs_remove_group(&sys_dev->kobj, &thermal_throttle_attr_group);
134 }
135
136 /* Mutex protecting device creation against CPU hotplug: */
137 static DEFINE_MUTEX(therm_cpu_lock);
138
139 /* Get notified when a cpu comes on/off. Be hotplug friendly. */
140 static __cpuinit int
141 thermal_throttle_cpu_callback(struct notifier_block *nfb,
142                               unsigned long action,
143                               void *hcpu)
144 {
145         unsigned int cpu = (unsigned long)hcpu;
146         struct sys_device *sys_dev;
147         int err = 0;
148
149         sys_dev = get_cpu_sysdev(cpu);
150
151         switch (action) {
152         case CPU_UP_PREPARE:
153         case CPU_UP_PREPARE_FROZEN:
154                 mutex_lock(&therm_cpu_lock);
155                 err = thermal_throttle_add_dev(sys_dev);
156                 mutex_unlock(&therm_cpu_lock);
157                 WARN_ON(err);
158                 break;
159         case CPU_UP_CANCELED:
160         case CPU_UP_CANCELED_FROZEN:
161         case CPU_DEAD:
162         case CPU_DEAD_FROZEN:
163                 mutex_lock(&therm_cpu_lock);
164                 thermal_throttle_remove_dev(sys_dev);
165                 mutex_unlock(&therm_cpu_lock);
166                 break;
167         }
168         return err ? NOTIFY_BAD : NOTIFY_OK;
169 }
170
171 static struct notifier_block thermal_throttle_cpu_notifier __cpuinitdata =
172 {
173         .notifier_call = thermal_throttle_cpu_callback,
174 };
175
176 static __init int thermal_throttle_init_device(void)
177 {
178         unsigned int cpu = 0;
179         int err;
180
181         if (!atomic_read(&therm_throt_en))
182                 return 0;
183
184         register_hotcpu_notifier(&thermal_throttle_cpu_notifier);
185
186 #ifdef CONFIG_HOTPLUG_CPU
187         mutex_lock(&therm_cpu_lock);
188 #endif
189         /* connect live CPUs to sysfs */
190         for_each_online_cpu(cpu) {
191                 err = thermal_throttle_add_dev(get_cpu_sysdev(cpu));
192                 WARN_ON(err);
193         }
194 #ifdef CONFIG_HOTPLUG_CPU
195         mutex_unlock(&therm_cpu_lock);
196 #endif
197
198         return 0;
199 }
200 device_initcall(thermal_throttle_init_device);
201
202 #endif /* CONFIG_SYSFS */
203
204 /* Thermal transition interrupt handler */
205 void intel_thermal_interrupt(void)
206 {
207         __u64 msr_val;
208
209         rdmsrl(MSR_IA32_THERM_STATUS, msr_val);
210         if (therm_throt_process(msr_val & THERM_STATUS_PROCHOT))
211                 mce_log_therm_throt_event(msr_val);
212 }
213
214 static void unexpected_thermal_interrupt(void)
215 {
216         printk(KERN_ERR "CPU%d: Unexpected LVT TMR interrupt!\n",
217                         smp_processor_id());
218         add_taint(TAINT_MACHINE_CHECK);
219 }
220
221 static void (*smp_thermal_vector)(void) = unexpected_thermal_interrupt;
222
223 asmlinkage void smp_thermal_interrupt(struct pt_regs *regs)
224 {
225         exit_idle();
226         irq_enter();
227         inc_irq_stat(irq_thermal_count);
228         smp_thermal_vector();
229         irq_exit();
230         /* Ack only at the end to avoid potential reentry */
231         ack_APIC_irq();
232 }
233
234 void intel_set_thermal_handler(void)
235 {
236         smp_thermal_vector = intel_thermal_interrupt;
237 }
238
239 void intel_init_thermal(struct cpuinfo_x86 *c)
240 {
241         unsigned int cpu = smp_processor_id();
242         int tm2 = 0;
243         u32 l, h;
244
245         /* Thermal monitoring depends on ACPI and clock modulation*/
246         if (!cpu_has(c, X86_FEATURE_ACPI) || !cpu_has(c, X86_FEATURE_ACC))
247                 return;
248
249         /*
250          * First check if its enabled already, in which case there might
251          * be some SMM goo which handles it, so we can't even put a handler
252          * since it might be delivered via SMI already:
253          */
254         rdmsr(MSR_IA32_MISC_ENABLE, l, h);
255         h = apic_read(APIC_LVTTHMR);
256         if ((l & MSR_IA32_MISC_ENABLE_TM1) && (h & APIC_DM_SMI)) {
257                 printk(KERN_DEBUG
258                        "CPU%d: Thermal monitoring handled by SMI\n", cpu);
259                 return;
260         }
261
262         if (cpu_has(c, X86_FEATURE_TM2) && (l & MSR_IA32_MISC_ENABLE_TM2))
263                 tm2 = 1;
264
265         /* Check whether a vector already exists */
266         if (h & APIC_VECTOR_MASK) {
267                 printk(KERN_DEBUG
268                        "CPU%d: Thermal LVT vector (%#x) already installed\n",
269                        cpu, (h & APIC_VECTOR_MASK));
270                 return;
271         }
272
273         /* We'll mask the thermal vector in the lapic till we're ready: */
274         h = THERMAL_APIC_VECTOR | APIC_DM_FIXED | APIC_LVT_MASKED;
275         apic_write(APIC_LVTTHMR, h);
276
277         rdmsr(MSR_IA32_THERM_INTERRUPT, l, h);
278         wrmsr(MSR_IA32_THERM_INTERRUPT,
279                 l | (THERM_INT_LOW_ENABLE | THERM_INT_HIGH_ENABLE), h);
280
281         intel_set_thermal_handler();
282
283         rdmsr(MSR_IA32_MISC_ENABLE, l, h);
284         wrmsr(MSR_IA32_MISC_ENABLE, l | MSR_IA32_MISC_ENABLE_TM1, h);
285
286         /* Unmask the thermal vector: */
287         l = apic_read(APIC_LVTTHMR);
288         apic_write(APIC_LVTTHMR, l & ~APIC_LVT_MASKED);
289
290         printk(KERN_INFO "CPU%d: Thermal monitoring enabled (%s)\n",
291                cpu, tm2 ? "TM2" : "TM1");
292
293         /* enable thermal throttle processing */
294         atomic_set(&therm_throt_en, 1);
295 }