Thermal: CPU Package temperature thermal
This driver register CPU digital temperature sensor as a thermal
zone at package level.
Each package will show up as one zone with at max two trip points.
These trip points can be both read and updated. Once a non zero
value is set in the trip point, if the package package temperature
goes above or below this setting, a thermal notification is
generated.
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
diff --git a/drivers/thermal/x86_pkg_temp_thermal.c b/drivers/thermal/x86_pkg_temp_thermal.c
new file mode 100644
index 0000000..5de56f6
--- /dev/null
+++ b/drivers/thermal/x86_pkg_temp_thermal.c
@@ -0,0 +1,642 @@
+/*
+ * x86_pkg_temp_thermal driver
+ * Copyright (c) 2013, Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc.
+ *
+ */
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/err.h>
+#include <linux/param.h>
+#include <linux/device.h>
+#include <linux/platform_device.h>
+#include <linux/cpu.h>
+#include <linux/smp.h>
+#include <linux/slab.h>
+#include <linux/pm.h>
+#include <linux/thermal.h>
+#include <linux/debugfs.h>
+#include <asm/cpu_device_id.h>
+#include <asm/mce.h>
+
+/*
+* Rate control delay: Idea is to introduce denounce effect
+* This should be long enough to avoid reduce events, when
+* threshold is set to a temperature, which is constantly
+* violated, but at the short enough to take any action.
+* The action can be remove threshold or change it to next
+* interesting setting. Based on experiments, in around
+* every 5 seconds under load will give us a significant
+* temperature change.
+*/
+#define PKG_TEMP_THERMAL_NOTIFY_DELAY 5000
+static int notify_delay_ms = PKG_TEMP_THERMAL_NOTIFY_DELAY;
+module_param(notify_delay_ms, int, 0644);
+MODULE_PARM_DESC(notify_delay_ms,
+ "User space notification delay in milli seconds.");
+
+/* Number of trip points in thermal zone. Currently it can't
+* be more than 2. MSR can allow setting and getting notifications
+* for only 2 thresholds. This define enforces this, if there
+* is some wrong values returned by cpuid for number of thresholds.
+*/
+#define MAX_NUMBER_OF_TRIPS 2
+
+struct phy_dev_entry {
+ struct list_head list;
+ u16 phys_proc_id;
+ u16 first_cpu;
+ u32 tj_max;
+ int ref_cnt;
+ u32 start_pkg_therm_low;
+ u32 start_pkg_therm_high;
+ struct thermal_zone_device *tzone;
+};
+
+/* List maintaining number of package instances */
+static LIST_HEAD(phy_dev_list);
+static DEFINE_MUTEX(phy_dev_list_mutex);
+
+/* Interrupt to work function schedule queue */
+static DEFINE_PER_CPU(struct delayed_work, pkg_temp_thermal_threshold_work);
+
+/* To track if the work is already scheduled on a package */
+static u8 *pkg_work_scheduled;
+
+/* Spin lock to prevent races with pkg_work_scheduled */
+static spinlock_t pkg_work_lock;
+static u16 max_phy_id;
+
+/* Debug counters to show using debugfs */
+static struct dentry *debugfs;
+static unsigned int pkg_interrupt_cnt;
+static unsigned int pkg_work_cnt;
+
+static int pkg_temp_debugfs_init(void)
+{
+ struct dentry *d;
+
+ debugfs = debugfs_create_dir("pkg_temp_thermal", NULL);
+ if (!debugfs)
+ return -ENOENT;
+
+ d = debugfs_create_u32("pkg_thres_interrupt", S_IRUGO, debugfs,
+ (u32 *)&pkg_interrupt_cnt);
+ if (!d)
+ goto err_out;
+
+ d = debugfs_create_u32("pkg_thres_work", S_IRUGO, debugfs,
+ (u32 *)&pkg_work_cnt);
+ if (!d)
+ goto err_out;
+
+ return 0;
+
+err_out:
+ debugfs_remove_recursive(debugfs);
+ return -ENOENT;
+}
+
+static struct phy_dev_entry
+ *pkg_temp_thermal_get_phy_entry(unsigned int cpu)
+{
+ u16 phys_proc_id = topology_physical_package_id(cpu);
+ struct phy_dev_entry *phy_ptr;
+
+ mutex_lock(&phy_dev_list_mutex);
+
+ list_for_each_entry(phy_ptr, &phy_dev_list, list)
+ if (phy_ptr->phys_proc_id == phys_proc_id) {
+ mutex_unlock(&phy_dev_list_mutex);
+ return phy_ptr;
+ }
+
+ mutex_unlock(&phy_dev_list_mutex);
+
+ return NULL;
+}
+
+/*
+* tj-max is is interesting because threshold is set relative to this
+* temperature.
+*/
+static int get_tj_max(int cpu, u32 *tj_max)
+{
+ u32 eax, edx;
+ u32 val;
+ int err;
+
+ err = rdmsr_safe_on_cpu(cpu, MSR_IA32_TEMPERATURE_TARGET, &eax, &edx);
+ if (err)
+ goto err_ret;
+ else {
+ val = (eax >> 16) & 0xff;
+ if (val)
+ *tj_max = val * 1000;
+ else {
+ err = -EINVAL;
+ goto err_ret;
+ }
+ }
+
+ return 0;
+err_ret:
+ *tj_max = 0;
+ return err;
+}
+
+static int sys_get_curr_temp(struct thermal_zone_device *tzd, unsigned long *temp)
+{
+ u32 eax, edx;
+ struct phy_dev_entry *phy_dev_entry;
+
+ phy_dev_entry = tzd->devdata;
+ rdmsr_on_cpu(phy_dev_entry->first_cpu, MSR_IA32_PACKAGE_THERM_STATUS,
+ &eax, &edx);
+ if (eax & 0x80000000) {
+ *temp = phy_dev_entry->tj_max -
+ ((eax >> 16) & 0x7f) * 1000;
+ pr_debug("sys_get_curr_temp %ld\n", *temp);
+ return 0;
+ }
+
+ return -EINVAL;
+}
+
+static int sys_get_trip_temp(struct thermal_zone_device *tzd,
+ int trip, unsigned long *temp)
+{
+ u32 eax, edx;
+ struct phy_dev_entry *phy_dev_entry;
+ u32 mask, shift;
+ unsigned long thres_reg_value;
+ int ret;
+
+ if (trip >= MAX_NUMBER_OF_TRIPS)
+ return -EINVAL;
+
+ phy_dev_entry = tzd->devdata;
+
+ if (trip) {
+ mask = THERM_MASK_THRESHOLD1;
+ shift = THERM_SHIFT_THRESHOLD1;
+ } else {
+ mask = THERM_MASK_THRESHOLD0;
+ shift = THERM_SHIFT_THRESHOLD0;
+ }
+
+ ret = rdmsr_on_cpu(phy_dev_entry->first_cpu,
+ MSR_IA32_PACKAGE_THERM_INTERRUPT, &eax, &edx);
+ if (ret < 0)
+ return -EINVAL;
+
+ thres_reg_value = (eax & mask) >> shift;
+ if (thres_reg_value)
+ *temp = phy_dev_entry->tj_max - thres_reg_value * 1000;
+ else
+ *temp = 0;
+ pr_debug("sys_get_trip_temp %ld\n", *temp);
+
+ return 0;
+}
+
+int sys_set_trip_temp(struct thermal_zone_device *tzd, int trip,
+ unsigned long temp)
+{
+ u32 l, h;
+ struct phy_dev_entry *phy_dev_entry;
+ u32 mask, shift, intr;
+ int ret;
+
+ phy_dev_entry = tzd->devdata;
+
+ if (trip >= MAX_NUMBER_OF_TRIPS || temp >= phy_dev_entry->tj_max)
+ return -EINVAL;
+
+ ret = rdmsr_on_cpu(phy_dev_entry->first_cpu,
+ MSR_IA32_PACKAGE_THERM_INTERRUPT,
+ &l, &h);
+ if (ret < 0)
+ return -EINVAL;
+
+ if (trip) {
+ mask = THERM_MASK_THRESHOLD1;
+ shift = THERM_SHIFT_THRESHOLD1;
+ intr = THERM_INT_THRESHOLD1_ENABLE;
+ } else {
+ mask = THERM_MASK_THRESHOLD0;
+ shift = THERM_SHIFT_THRESHOLD0;
+ intr = THERM_INT_THRESHOLD0_ENABLE;
+ }
+ l &= ~mask;
+ /*
+ * When users space sets a trip temperature == 0, which is indication
+ * that, it is no longer interested in receiving notifications.
+ */
+ if (!temp)
+ l &= ~intr;
+ else {
+ l |= (phy_dev_entry->tj_max - temp)/1000 << shift;
+ l |= intr;
+ }
+
+ return wrmsr_on_cpu(phy_dev_entry->first_cpu,
+ MSR_IA32_PACKAGE_THERM_INTERRUPT,
+ l, h);
+}
+
+static int sys_get_trip_type(struct thermal_zone_device *thermal,
+ int trip, enum thermal_trip_type *type)
+{
+
+ *type = THERMAL_TRIP_PASSIVE;
+
+ return 0;
+}
+
+/* Thermal zone callback registry */
+static struct thermal_zone_device_ops tzone_ops = {
+ .get_temp = sys_get_curr_temp,
+ .get_trip_temp = sys_get_trip_temp,
+ .get_trip_type = sys_get_trip_type,
+ .set_trip_temp = sys_set_trip_temp,
+};
+
+static bool pkg_temp_thermal_platform_thermal_rate_control(void)
+{
+ return true;
+}
+
+/* Enable threshold interrupt on local package/cpu */
+static inline void enable_pkg_thres_interrupt(void)
+{
+ u32 l, h;
+ u8 thres_0, thres_1;
+
+ rdmsr(MSR_IA32_PACKAGE_THERM_INTERRUPT, l, h);
+ /* only enable/disable if it had valid threshold value */
+ thres_0 = (l & THERM_MASK_THRESHOLD0) >> THERM_SHIFT_THRESHOLD0;
+ thres_1 = (l & THERM_MASK_THRESHOLD1) >> THERM_SHIFT_THRESHOLD1;
+ if (thres_0)
+ l |= THERM_INT_THRESHOLD0_ENABLE;
+ if (thres_1)
+ l |= THERM_INT_THRESHOLD1_ENABLE;
+ wrmsr(MSR_IA32_PACKAGE_THERM_INTERRUPT, l, h);
+}
+
+/* Disable threshold interrupt on local package/cpu */
+static inline void disable_pkg_thres_interrupt(void)
+{
+ u32 l, h;
+ rdmsr(MSR_IA32_PACKAGE_THERM_INTERRUPT, l, h);
+ wrmsr(MSR_IA32_PACKAGE_THERM_INTERRUPT,
+ l & (~THERM_INT_THRESHOLD0_ENABLE) &
+ (~THERM_INT_THRESHOLD1_ENABLE), h);
+}
+
+static void pkg_temp_thermal_threshold_work_fn(struct work_struct *work)
+{
+ __u64 msr_val;
+ int cpu = smp_processor_id();
+ int phy_id = topology_physical_package_id(cpu);
+ struct phy_dev_entry *phdev = pkg_temp_thermal_get_phy_entry(cpu);
+ bool notify = false;
+
+ if (!phdev)
+ return;
+
+ spin_lock(&pkg_work_lock);
+ ++pkg_work_cnt;
+ if (unlikely(phy_id > max_phy_id)) {
+ spin_unlock(&pkg_work_lock);
+ return;
+ }
+ pkg_work_scheduled[phy_id] = 0;
+ spin_unlock(&pkg_work_lock);
+
+ enable_pkg_thres_interrupt();
+ rdmsrl(MSR_IA32_PACKAGE_THERM_STATUS, msr_val);
+ if (msr_val & THERM_LOG_THRESHOLD0) {
+ wrmsrl(MSR_IA32_PACKAGE_THERM_STATUS,
+ msr_val & ~THERM_LOG_THRESHOLD0);
+ notify = true;
+ }
+ if (msr_val & THERM_LOG_THRESHOLD1) {
+ wrmsrl(MSR_IA32_PACKAGE_THERM_STATUS,
+ msr_val & ~THERM_LOG_THRESHOLD1);
+ notify = true;
+ }
+ if (notify) {
+ pr_debug("thermal_zone_device_update\n");
+ thermal_zone_device_update(phdev->tzone);
+ }
+}
+
+static int pkg_temp_thermal_platform_thermal_notify(__u64 msr_val)
+{
+ unsigned long flags;
+ int cpu = smp_processor_id();
+ int phy_id = topology_physical_package_id(cpu);
+
+ /*
+ * When a package is in interrupted state, all CPU's in that package
+ * are in the same interrupt state. So scheduling on any one CPU in
+ * the package is enough and simply return for others.
+ */
+ spin_lock_irqsave(&pkg_work_lock, flags);
+ ++pkg_interrupt_cnt;
+ if (unlikely(phy_id > max_phy_id) || unlikely(!pkg_work_scheduled) ||
+ pkg_work_scheduled[phy_id]) {
+ disable_pkg_thres_interrupt();
+ spin_unlock_irqrestore(&pkg_work_lock, flags);
+ return -EINVAL;
+ }
+ pkg_work_scheduled[phy_id] = 1;
+ spin_unlock_irqrestore(&pkg_work_lock, flags);
+
+ disable_pkg_thres_interrupt();
+ schedule_delayed_work_on(cpu,
+ &per_cpu(pkg_temp_thermal_threshold_work, cpu),
+ msecs_to_jiffies(notify_delay_ms));
+ return 0;
+}
+
+static int find_siblings_cpu(int cpu)
+{
+ int i;
+ int id = topology_physical_package_id(cpu);
+
+ for_each_online_cpu(i)
+ if (i != cpu && topology_physical_package_id(i) == id)
+ return i;
+
+ return 0;
+}
+
+static int pkg_temp_thermal_device_add(unsigned int cpu)
+{
+ int err;
+ u32 tj_max;
+ struct phy_dev_entry *phy_dev_entry;
+ char buffer[30];
+ int thres_count;
+ u32 eax, ebx, ecx, edx;
+
+ cpuid(6, &eax, &ebx, &ecx, &edx);
+ thres_count = ebx & 0x07;
+ if (!thres_count)
+ return -ENODEV;
+
+ thres_count = clamp_val(thres_count, 0, MAX_NUMBER_OF_TRIPS);
+
+ err = get_tj_max(cpu, &tj_max);
+ if (err)
+ goto err_ret;
+
+ mutex_lock(&phy_dev_list_mutex);
+
+ phy_dev_entry = kzalloc(sizeof(*phy_dev_entry), GFP_KERNEL);
+ if (!phy_dev_entry) {
+ err = -ENOMEM;
+ goto err_ret_unlock;
+ }
+
+ spin_lock(&pkg_work_lock);
+ if (topology_physical_package_id(cpu) > max_phy_id)
+ max_phy_id = topology_physical_package_id(cpu);
+ pkg_work_scheduled = krealloc(pkg_work_scheduled,
+ (max_phy_id+1) * sizeof(u8), GFP_ATOMIC);
+ if (!pkg_work_scheduled) {
+ spin_unlock(&pkg_work_lock);
+ err = -ENOMEM;
+ goto err_ret_free;
+ }
+ pkg_work_scheduled[topology_physical_package_id(cpu)] = 0;
+ spin_unlock(&pkg_work_lock);
+
+ phy_dev_entry->phys_proc_id = topology_physical_package_id(cpu);
+ phy_dev_entry->first_cpu = cpu;
+ phy_dev_entry->tj_max = tj_max;
+ phy_dev_entry->ref_cnt = 1;
+ snprintf(buffer, sizeof(buffer), "pkg-temp-%d\n",
+ phy_dev_entry->phys_proc_id);
+ phy_dev_entry->tzone = thermal_zone_device_register(buffer,
+ thres_count,
+ (thres_count == MAX_NUMBER_OF_TRIPS) ?
+ 0x03 : 0x01,
+ phy_dev_entry, &tzone_ops, NULL, 0, 0);
+ if (IS_ERR(phy_dev_entry->tzone)) {
+ err = PTR_ERR(phy_dev_entry->tzone);
+ goto err_ret_free;
+ }
+ /* Store MSR value for package thermal interrupt, to restore at exit */
+ rdmsr_on_cpu(cpu, MSR_IA32_PACKAGE_THERM_INTERRUPT,
+ &phy_dev_entry->start_pkg_therm_low,
+ &phy_dev_entry->start_pkg_therm_high);
+
+ list_add_tail(&phy_dev_entry->list, &phy_dev_list);
+ pr_debug("pkg_temp_thermal_device_add :phy_id %d cpu %d\n",
+ phy_dev_entry->phys_proc_id, cpu);
+
+ mutex_unlock(&phy_dev_list_mutex);
+
+ return 0;
+
+err_ret_free:
+ kfree(phy_dev_entry);
+err_ret_unlock:
+ mutex_unlock(&phy_dev_list_mutex);
+
+err_ret:
+ return err;
+}
+
+static int pkg_temp_thermal_device_remove(unsigned int cpu)
+{
+ struct phy_dev_entry *n;
+ u16 phys_proc_id = topology_physical_package_id(cpu);
+ struct phy_dev_entry *phdev =
+ pkg_temp_thermal_get_phy_entry(cpu);
+
+ if (!phdev)
+ return -ENODEV;
+
+ mutex_lock(&phy_dev_list_mutex);
+ /* If we are loosing the first cpu for this package, we need change */
+ if (phdev->first_cpu == cpu) {
+ phdev->first_cpu = find_siblings_cpu(cpu);
+ pr_debug("thermal_device_remove: first cpu switched %d\n",
+ phdev->first_cpu);
+ }
+ /*
+ * It is possible that no siblings left as this was the last cpu
+ * going offline. We don't need to worry about this assignment
+ * as the phydev entry will be removed in this case and
+ * thermal zone is removed.
+ */
+ --phdev->ref_cnt;
+ pr_debug("thermal_device_remove: pkg: %d cpu %d ref_cnt %d\n",
+ phys_proc_id, cpu, phdev->ref_cnt);
+ if (!phdev->ref_cnt)
+ list_for_each_entry_safe(phdev, n, &phy_dev_list, list) {
+ if (phdev->phys_proc_id == phys_proc_id) {
+ thermal_zone_device_unregister(phdev->tzone);
+ list_del(&phdev->list);
+ kfree(phdev);
+ break;
+ }
+ }
+ mutex_unlock(&phy_dev_list_mutex);
+
+ return 0;
+}
+
+static int get_core_online(unsigned int cpu)
+{
+ struct cpuinfo_x86 *c = &cpu_data(cpu);
+ struct phy_dev_entry *phdev = pkg_temp_thermal_get_phy_entry(cpu);
+
+ /* Check if there is already an instance for this package */
+ if (!phdev) {
+ if (!cpu_has(c, X86_FEATURE_DTHERM) &&
+ !cpu_has(c, X86_FEATURE_PTS))
+ return -ENODEV;
+ if (pkg_temp_thermal_device_add(cpu))
+ return -ENODEV;
+ } else {
+ mutex_lock(&phy_dev_list_mutex);
+ ++phdev->ref_cnt;
+ pr_debug("get_core_online: cpu %d ref_cnt %d\n",
+ cpu, phdev->ref_cnt);
+ mutex_unlock(&phy_dev_list_mutex);
+ }
+ INIT_DELAYED_WORK(&per_cpu(pkg_temp_thermal_threshold_work, cpu),
+ pkg_temp_thermal_threshold_work_fn);
+
+ pr_debug("get_core_online: cpu %d successful\n", cpu);
+
+ return 0;
+}
+
+static void put_core_offline(unsigned int cpu)
+{
+ if (!pkg_temp_thermal_device_remove(cpu))
+ cancel_delayed_work_sync(
+ &per_cpu(pkg_temp_thermal_threshold_work, cpu));
+
+ pr_debug("put_core_offline: cpu %d\n", cpu);
+}
+
+static int pkg_temp_thermal_cpu_callback(struct notifier_block *nfb,
+ unsigned long action, void *hcpu)
+{
+ unsigned int cpu = (unsigned long) hcpu;
+
+ switch (action) {
+ case CPU_ONLINE:
+ case CPU_DOWN_FAILED:
+ get_core_online(cpu);
+ break;
+ case CPU_DOWN_PREPARE:
+ put_core_offline(cpu);
+ break;
+ }
+ return NOTIFY_OK;
+}
+
+static struct notifier_block pkg_temp_thermal_notifier __refdata = {
+ .notifier_call = pkg_temp_thermal_cpu_callback,
+};
+
+static const struct x86_cpu_id __initconst pkg_temp_thermal_ids[] = {
+ { X86_VENDOR_INTEL, X86_FAMILY_ANY, X86_MODEL_ANY, X86_FEATURE_DTHERM },
+ {}
+};
+MODULE_DEVICE_TABLE(x86cpu, pkg_temp_thermal_ids);
+
+static int __init pkg_temp_thermal_init(void)
+{
+ int i;
+
+ if (!x86_match_cpu(pkg_temp_thermal_ids))
+ return -ENODEV;
+
+ spin_lock_init(&pkg_work_lock);
+ platform_thermal_package_notify =
+ pkg_temp_thermal_platform_thermal_notify;
+ platform_thermal_package_rate_control =
+ pkg_temp_thermal_platform_thermal_rate_control;
+
+ get_online_cpus();
+ for_each_online_cpu(i)
+ if (get_core_online(i))
+ goto err_ret;
+ register_hotcpu_notifier(&pkg_temp_thermal_notifier);
+ put_online_cpus();
+
+ pkg_temp_debugfs_init(); /* Don't care if fails */
+
+ return 0;
+
+err_ret:
+ get_online_cpus();
+ for_each_online_cpu(i)
+ put_core_offline(i);
+ put_online_cpus();
+ kfree(pkg_work_scheduled);
+ platform_thermal_package_notify = NULL;
+ platform_thermal_package_rate_control = NULL;
+
+ return -ENODEV;
+}
+
+static void __exit pkg_temp_thermal_exit(void)
+{
+ struct phy_dev_entry *phdev, *n;
+ int i;
+
+ get_online_cpus();
+ unregister_hotcpu_notifier(&pkg_temp_thermal_notifier);
+ mutex_lock(&phy_dev_list_mutex);
+ list_for_each_entry_safe(phdev, n, &phy_dev_list, list) {
+ /* Retore old MSR value for package thermal interrupt */
+ wrmsr_on_cpu(phdev->first_cpu,
+ MSR_IA32_PACKAGE_THERM_INTERRUPT,
+ phdev->start_pkg_therm_low,
+ phdev->start_pkg_therm_high);
+ thermal_zone_device_unregister(phdev->tzone);
+ list_del(&phdev->list);
+ kfree(phdev);
+ }
+ mutex_unlock(&phy_dev_list_mutex);
+ platform_thermal_package_notify = NULL;
+ platform_thermal_package_rate_control = NULL;
+ for_each_online_cpu(i)
+ cancel_delayed_work_sync(
+ &per_cpu(pkg_temp_thermal_threshold_work, i));
+ put_online_cpus();
+
+ kfree(pkg_work_scheduled);
+
+ debugfs_remove_recursive(debugfs);
+}
+
+module_init(pkg_temp_thermal_init)
+module_exit(pkg_temp_thermal_exit)
+
+MODULE_DESCRIPTION("X86 PKG TEMP Thermal Driver");
+MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");
+MODULE_LICENSE("GPL v2");