* Credits: Adapted from Zwane Mwaikambo's original code in mce_intel.c.
* Inspired by Ross Biro's and Al Borchers' counter code.
*/
+#include <linux/interrupt.h>
#include <linux/notifier.h>
#include <linux/jiffies.h>
+#include <linux/kernel.h>
#include <linux/percpu.h>
#include <linux/sysdev.h>
+#include <linux/types.h>
+#include <linux/init.h>
+#include <linux/smp.h>
#include <linux/cpu.h>
-#include <asm/therm_throt.h>
-#include <asm/cpu.h>
+#include <asm/processor.h>
+#include <asm/system.h>
+#include <asm/apic.h>
+#include <asm/idle.h>
+#include <asm/mce.h>
+#include <asm/msr.h>
/* How long to wait between reporting thermal events */
#define CHECK_INTERVAL (300 * HZ)
-static DEFINE_PER_CPU(__u64, next_check) = INITIAL_JIFFIES;
-static DEFINE_PER_CPU(unsigned long, thermal_throttle_count);
+/*
+ * Current thermal throttling state:
+ */
+struct thermal_state {
+ bool is_throttled;
+
+ u64 next_check;
+ unsigned long throttle_count;
+ unsigned long last_throttle_count;
+};
-atomic_t therm_throt_en = ATOMIC_INIT(0);
+static DEFINE_PER_CPU(struct thermal_state, thermal_state);
+
+static atomic_t therm_throt_en = ATOMIC_INIT(0);
+
+static u32 lvtthmr_init __read_mostly;
#ifdef CONFIG_SYSFS
#define define_therm_throt_sysdev_one_ro(_name) \
static SYSDEV_ATTR(_name, 0444, therm_throt_sysdev_show_##_name, NULL)
#define define_therm_throt_sysdev_show_func(name) \
-static ssize_t therm_throt_sysdev_show_##name(struct sys_device *dev, \
- struct sysdev_attribute *attr, \
- char *buf) \
+ \
+static ssize_t therm_throt_sysdev_show_##name( \
+ struct sys_device *dev, \
+ struct sysdev_attribute *attr, \
+ char *buf) \
{ \
unsigned int cpu = dev->id; \
ssize_t ret; \
preempt_disable(); /* CPU hotplug */ \
if (cpu_online(cpu)) \
ret = sprintf(buf, "%lu\n", \
- per_cpu(thermal_throttle_##name, cpu)); \
+ per_cpu(thermal_state, cpu).name); \
else \
ret = 0; \
preempt_enable(); \
return ret; \
}
-define_therm_throt_sysdev_show_func(count);
-define_therm_throt_sysdev_one_ro(count);
+define_therm_throt_sysdev_show_func(throttle_count);
+define_therm_throt_sysdev_one_ro(throttle_count);
static struct attribute *thermal_throttle_attrs[] = {
- &attr_count.attr,
+ &attr_throttle_count.attr,
NULL
};
* 1 : Event should be logged further, and a message has been
* printed to the syslog.
*/
-int therm_throt_process(int curr)
+static int therm_throt_process(bool is_throttled)
{
- unsigned int cpu = smp_processor_id();
- __u64 tmp_jiffs = get_jiffies_64();
+ struct thermal_state *state;
+ unsigned int this_cpu;
+ bool was_throttled;
+ u64 now;
+
+ this_cpu = smp_processor_id();
+ now = get_jiffies_64();
+ state = &per_cpu(thermal_state, this_cpu);
- if (curr)
- __get_cpu_var(thermal_throttle_count)++;
+ was_throttled = state->is_throttled;
+ state->is_throttled = is_throttled;
- if (time_before64(tmp_jiffs, __get_cpu_var(next_check)))
+ if (is_throttled)
+ state->throttle_count++;
+
+ if (time_before64(now, state->next_check) &&
+ state->throttle_count != state->last_throttle_count)
return 0;
- __get_cpu_var(next_check) = tmp_jiffs + CHECK_INTERVAL;
+ state->next_check = now + CHECK_INTERVAL;
+ state->last_throttle_count = state->throttle_count;
/* if we just entered the thermal event */
- if (curr) {
- printk(KERN_CRIT "CPU%d: Temperature above threshold, "
- "cpu clock throttled (total events = %lu)\n", cpu,
- __get_cpu_var(thermal_throttle_count));
+ if (is_throttled) {
+ printk(KERN_CRIT "CPU%d: Temperature above threshold, cpu clock throttled (total events = %lu)\n", this_cpu, state->throttle_count);
add_taint(TAINT_MACHINE_CHECK);
- } else {
- printk(KERN_CRIT "CPU%d: Temperature/speed normal\n", cpu);
+ return 1;
+ }
+ if (was_throttled) {
+ printk(KERN_INFO "CPU%d: Temperature/speed normal\n", this_cpu);
+ return 1;
}
- return 1;
+ return 0;
}
#ifdef CONFIG_SYSFS
mutex_unlock(&therm_cpu_lock);
break;
}
- return err ? NOTIFY_BAD : NOTIFY_OK;
+ return notifier_from_errno(err);
}
static struct notifier_block thermal_throttle_cpu_notifier __cpuinitdata =
return 0;
}
-
device_initcall(thermal_throttle_init_device);
+
#endif /* CONFIG_SYSFS */
+
+/* Thermal transition interrupt handler */
+static void intel_thermal_interrupt(void)
+{
+ __u64 msr_val;
+
+ rdmsrl(MSR_IA32_THERM_STATUS, msr_val);
+ if (therm_throt_process((msr_val & THERM_STATUS_PROCHOT) != 0))
+ mce_log_therm_throt_event(msr_val);
+}
+
+static void unexpected_thermal_interrupt(void)
+{
+ printk(KERN_ERR "CPU%d: Unexpected LVT TMR interrupt!\n",
+ smp_processor_id());
+ add_taint(TAINT_MACHINE_CHECK);
+}
+
+static void (*smp_thermal_vector)(void) = unexpected_thermal_interrupt;
+
+asmlinkage void smp_thermal_interrupt(struct pt_regs *regs)
+{
+ exit_idle();
+ irq_enter();
+ inc_irq_stat(irq_thermal_count);
+ smp_thermal_vector();
+ irq_exit();
+ /* Ack only at the end to avoid potential reentry */
+ ack_APIC_irq();
+}
+
+/* Thermal monitoring depends on APIC, ACPI and clock modulation */
+static int intel_thermal_supported(struct cpuinfo_x86 *c)
+{
+ if (!cpu_has_apic)
+ return 0;
+ if (!cpu_has(c, X86_FEATURE_ACPI) || !cpu_has(c, X86_FEATURE_ACC))
+ return 0;
+ return 1;
+}
+
+void __init mcheck_intel_therm_init(void)
+{
+ /*
+ * This function is only called on boot CPU. Save the init thermal
+ * LVT value on BSP and use that value to restore APs' thermal LVT
+ * entry BIOS programmed later
+ */
+ if (intel_thermal_supported(&boot_cpu_data))
+ lvtthmr_init = apic_read(APIC_LVTTHMR);
+}
+
+void intel_init_thermal(struct cpuinfo_x86 *c)
+{
+ unsigned int cpu = smp_processor_id();
+ int tm2 = 0;
+ u32 l, h;
+
+ if (!intel_thermal_supported(c))
+ return;
+
+ /*
+ * First check if its enabled already, in which case there might
+ * be some SMM goo which handles it, so we can't even put a handler
+ * since it might be delivered via SMI already:
+ */
+ rdmsr(MSR_IA32_MISC_ENABLE, l, h);
+
+ /*
+ * The initial value of thermal LVT entries on all APs always reads
+ * 0x10000 because APs are woken up by BSP issuing INIT-SIPI-SIPI
+ * sequence to them and LVT registers are reset to 0s except for
+ * the mask bits which are set to 1s when APs receive INIT IPI.
+ * Always restore the value that BIOS has programmed on AP based on
+ * BSP's info we saved since BIOS is always setting the same value
+ * for all threads/cores
+ */
+ apic_write(APIC_LVTTHMR, lvtthmr_init);
+
+ h = lvtthmr_init;
+
+ if ((l & MSR_IA32_MISC_ENABLE_TM1) && (h & APIC_DM_SMI)) {
+ printk(KERN_DEBUG
+ "CPU%d: Thermal monitoring handled by SMI\n", cpu);
+ return;
+ }
+
+ /* Check whether a vector already exists */
+ if (h & APIC_VECTOR_MASK) {
+ printk(KERN_DEBUG
+ "CPU%d: Thermal LVT vector (%#x) already installed\n",
+ cpu, (h & APIC_VECTOR_MASK));
+ return;
+ }
+
+ /* early Pentium M models use different method for enabling TM2 */
+ if (cpu_has(c, X86_FEATURE_TM2)) {
+ if (c->x86 == 6 && (c->x86_model == 9 || c->x86_model == 13)) {
+ rdmsr(MSR_THERM2_CTL, l, h);
+ if (l & MSR_THERM2_CTL_TM_SELECT)
+ tm2 = 1;
+ } else if (l & MSR_IA32_MISC_ENABLE_TM2)
+ tm2 = 1;
+ }
+
+ /* We'll mask the thermal vector in the lapic till we're ready: */
+ h = THERMAL_APIC_VECTOR | APIC_DM_FIXED | APIC_LVT_MASKED;
+ apic_write(APIC_LVTTHMR, h);
+
+ rdmsr(MSR_IA32_THERM_INTERRUPT, l, h);
+ wrmsr(MSR_IA32_THERM_INTERRUPT,
+ l | (THERM_INT_LOW_ENABLE | THERM_INT_HIGH_ENABLE), h);
+
+ smp_thermal_vector = intel_thermal_interrupt;
+
+ rdmsr(MSR_IA32_MISC_ENABLE, l, h);
+ wrmsr(MSR_IA32_MISC_ENABLE, l | MSR_IA32_MISC_ENABLE_TM1, h);
+
+ /* Unmask the thermal vector: */
+ l = apic_read(APIC_LVTTHMR);
+ apic_write(APIC_LVTTHMR, l & ~APIC_LVT_MASKED);
+
+ printk_once(KERN_INFO "CPU0: Thermal monitoring enabled (%s)\n",
+ tm2 ? "TM2" : "TM1");
+
+ /* enable thermal throttle processing */
+ atomic_set(&therm_throt_en, 1);
+}