1 files changed, 558 insertions, 0 deletions
diff --git a/drivers/thermal/intel/x86_pkg_temp_thermal.c b/drivers/thermal/intel/x86_pkg_temp_thermal.c
new file mode 100644
index 000000000000..1ef937d799e4
--- /dev/null
+++ b/drivers/thermal/intel/x86_pkg_temp_thermal.c
@@ -0,0 +1,558 @@
+/*
+ * 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 pkg_device {
+	int				cpu;
+	bool				work_scheduled;
+	u32				tj_max;
+	u32				msr_pkg_therm_low;
+	u32				msr_pkg_therm_high;
+	struct delayed_work		work;
+	struct thermal_zone_device	*tzone;
+	struct cpumask			cpumask;
+};
+
+static struct thermal_zone_params pkg_temp_tz_params = {
+	.no_hwmon	= true,
+};
+
+/* Keep track of how many package pointers we allocated in init() */
+static int max_packages __read_mostly;
+/* Array of package pointers */
+static struct pkg_device **packages;
+/* Serializes interrupt notification, work and hotplug */
+static DEFINE_SPINLOCK(pkg_temp_lock);
+/* Protects zone operation in the work function against hotplug removal */
+static DEFINE_MUTEX(thermal_zone_mutex);
+
+/* The dynamically assigned cpu hotplug state for module_exit() */
+static enum cpuhp_state pkg_thermal_hp_state __read_mostly;
+
+/* 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,
+			       &pkg_interrupt_cnt);
+	if (!d)
+		goto err_out;
+
+	d = debugfs_create_u32("pkg_thres_work", S_IRUGO, debugfs,
+			       &pkg_work_cnt);
+	if (!d)
+		goto err_out;
+
+	return 0;
+
+err_out:
+	debugfs_remove_recursive(debugfs);
+	return -ENOENT;
+}
+
+/*
+ * Protection:
+ *
+ * - cpu hotplug: Read serialized by cpu hotplug lock
+ *		  Write must hold pkg_temp_lock
+ *
+ * - Other callsites: Must hold pkg_temp_lock
+ */
+static struct pkg_device *pkg_temp_thermal_get_dev(unsigned int cpu)
+{
+	int pkgid = topology_logical_package_id(cpu);
+
+	if (pkgid >= 0 && pkgid < max_packages)
+		return packages[pkgid];
+	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, val;
+	int err;
+
+	err = rdmsr_safe_on_cpu(cpu, MSR_IA32_TEMPERATURE_TARGET, &eax, &edx);
+	if (err)
+		return err;
+
+	val = (eax >> 16) & 0xff;
+	*tj_max = val * 1000;
+
+	return val ? 0 : -EINVAL;
+}
+
+static int sys_get_curr_temp(struct thermal_zone_device *tzd, int *temp)
+{
+	struct pkg_device *pkgdev = tzd->devdata;
+	u32 eax, edx;
+
+	rdmsr_on_cpu(pkgdev->cpu, MSR_IA32_PACKAGE_THERM_STATUS, &eax, &edx);
+	if (eax & 0x80000000) {
+		*temp = pkgdev->tj_max - ((eax >> 16) & 0x7f) * 1000;
+		pr_debug("sys_get_curr_temp %d\n", *temp);
+		return 0;
+	}
+	return -EINVAL;
+}
+
+static int sys_get_trip_temp(struct thermal_zone_device *tzd,
+			     int trip, int *temp)
+{
+	struct pkg_device *pkgdev = tzd->devdata;
+	unsigned long thres_reg_value;
+	u32 mask, shift, eax, edx;
+	int ret;
+
+	if (trip >= MAX_NUMBER_OF_TRIPS)
+		return -EINVAL;
+
+	if (trip) {
+		mask = THERM_MASK_THRESHOLD1;
+		shift = THERM_SHIFT_THRESHOLD1;
+	} else {
+		mask = THERM_MASK_THRESHOLD0;
+		shift = THERM_SHIFT_THRESHOLD0;
+	}
+
+	ret = rdmsr_on_cpu(pkgdev->cpu, MSR_IA32_PACKAGE_THERM_INTERRUPT,
+			   &eax, &edx);
+	if (ret < 0)
+		return ret;
+
+	thres_reg_value = (eax & mask) >> shift;
+	if (thres_reg_value)
+		*temp = pkgdev->tj_max - thres_reg_value * 1000;
+	else
+		*temp = 0;
+	pr_debug("sys_get_trip_temp %d\n", *temp);
+
+	return 0;
+}
+
+static int
+sys_set_trip_temp(struct thermal_zone_device *tzd, int trip, int temp)
+{
+	struct pkg_device *pkgdev = tzd->devdata;
+	u32 l, h, mask, shift, intr;
+	int ret;
+
+	if (trip >= MAX_NUMBER_OF_TRIPS || temp >= pkgdev->tj_max)
+		return -EINVAL;
+
+	ret = rdmsr_on_cpu(pkgdev->cpu, MSR_IA32_PACKAGE_THERM_INTERRUPT,
+			   &l, &h);
+	if (ret < 0)
+		return ret;
+
+	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 |= (pkgdev->tj_max - temp)/1000 << shift;
+		l |= intr;
+	}
+
+	return wrmsr_on_cpu(pkgdev->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_thermal_rate_control(void)
+{
+	return true;
+}
+
+/* Enable threshold interrupt on local package/cpu */
+static inline void enable_pkg_thres_interrupt(void)
+{
+	u8 thres_0, thres_1;
+	u32 l, h;
+
+	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);
+
+	l &= ~(THERM_INT_THRESHOLD0_ENABLE | THERM_INT_THRESHOLD1_ENABLE);
+	wrmsr(MSR_IA32_PACKAGE_THERM_INTERRUPT, l, h);
+}
+
+static void pkg_temp_thermal_threshold_work_fn(struct work_struct *work)
+{
+	struct thermal_zone_device *tzone = NULL;
+	int cpu = smp_processor_id();
+	struct pkg_device *pkgdev;
+	u64 msr_val, wr_val;
+
+	mutex_lock(&thermal_zone_mutex);
+	spin_lock_irq(&pkg_temp_lock);
+	++pkg_work_cnt;
+
+	pkgdev = pkg_temp_thermal_get_dev(cpu);
+	if (!pkgdev) {
+		spin_unlock_irq(&pkg_temp_lock);
+		mutex_unlock(&thermal_zone_mutex);
+		return;
+	}
+	pkgdev->work_scheduled = false;
+
+	rdmsrl(MSR_IA32_PACKAGE_THERM_STATUS, msr_val);
+	wr_val = msr_val & ~(THERM_LOG_THRESHOLD0 | THERM_LOG_THRESHOLD1);
+	if (wr_val != msr_val) {
+		wrmsrl(MSR_IA32_PACKAGE_THERM_STATUS, wr_val);
+		tzone = pkgdev->tzone;
+	}
+
+	enable_pkg_thres_interrupt();
+	spin_unlock_irq(&pkg_temp_lock);
+
+	/*
+	 * If tzone is not NULL, then thermal_zone_mutex will prevent the
+	 * concurrent removal in the cpu offline callback.
+	 */
+	if (tzone)
+		thermal_zone_device_update(tzone, THERMAL_EVENT_UNSPECIFIED);
+
+	mutex_unlock(&thermal_zone_mutex);
+}
+
+static void pkg_thermal_schedule_work(int cpu, struct delayed_work *work)
+{
+	unsigned long ms = msecs_to_jiffies(notify_delay_ms);
+
+	schedule_delayed_work_on(cpu, work, ms);
+}
+
+static int pkg_thermal_notify(u64 msr_val)
+{
+	int cpu = smp_processor_id();
+	struct pkg_device *pkgdev;
+	unsigned long flags;
+
+	spin_lock_irqsave(&pkg_temp_lock, flags);
+	++pkg_interrupt_cnt;
+
+	disable_pkg_thres_interrupt();
+
+	/* Work is per package, so scheduling it once is enough. */
+	pkgdev = pkg_temp_thermal_get_dev(cpu);
+	if (pkgdev && !pkgdev->work_scheduled) {
+		pkgdev->work_scheduled = true;
+		pkg_thermal_schedule_work(pkgdev->cpu, &pkgdev->work);
+	}
+
+	spin_unlock_irqrestore(&pkg_temp_lock, flags);
+	return 0;
+}
+
+static int pkg_temp_thermal_device_add(unsigned int cpu)
+{
+	int pkgid = topology_logical_package_id(cpu);
+	u32 tj_max, eax, ebx, ecx, edx;
+	struct pkg_device *pkgdev;
+	int thres_count, err;
+
+	if (pkgid >= max_packages)
+		return -ENOMEM;
+
+	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)
+		return err;
+
+	pkgdev = kzalloc(sizeof(*pkgdev), GFP_KERNEL);
+	if (!pkgdev)
+		return -ENOMEM;
+
+	INIT_DELAYED_WORK(&pkgdev->work, pkg_temp_thermal_threshold_work_fn);
+	pkgdev->cpu = cpu;
+	pkgdev->tj_max = tj_max;
+	pkgdev->tzone = thermal_zone_device_register("x86_pkg_temp",
+			thres_count,
+			(thres_count == MAX_NUMBER_OF_TRIPS) ? 0x03 : 0x01,
+			pkgdev, &tzone_ops, &pkg_temp_tz_params, 0, 0);
+	if (IS_ERR(pkgdev->tzone)) {
+		err = PTR_ERR(pkgdev->tzone);
+		kfree(pkgdev);
+		return err;
+	}
+	/* Store MSR value for package thermal interrupt, to restore at exit */
+	rdmsr(MSR_IA32_PACKAGE_THERM_INTERRUPT, pkgdev->msr_pkg_therm_low,
+	      pkgdev->msr_pkg_therm_high);
+
+	cpumask_set_cpu(cpu, &pkgdev->cpumask);
+	spin_lock_irq(&pkg_temp_lock);
+	packages[pkgid] = pkgdev;
+	spin_unlock_irq(&pkg_temp_lock);
+	return 0;
+}
+
+static int pkg_thermal_cpu_offline(unsigned int cpu)
+{
+	struct pkg_device *pkgdev = pkg_temp_thermal_get_dev(cpu);
+	bool lastcpu, was_target;
+	int target;
+
+	if (!pkgdev)
+		return 0;
+
+	target = cpumask_any_but(&pkgdev->cpumask, cpu);
+	cpumask_clear_cpu(cpu, &pkgdev->cpumask);
+	lastcpu = target >= nr_cpu_ids;
+	/*
+	 * Remove the sysfs files, if this is the last cpu in the package
+	 * before doing further cleanups.
+	 */
+	if (lastcpu) {
+		struct thermal_zone_device *tzone = pkgdev->tzone;
+
+		/*
+		 * We must protect against a work function calling
+		 * thermal_zone_update, after/while unregister. We null out
+		 * the pointer under the zone mutex, so the worker function
+		 * won't try to call.
+		 */
+		mutex_lock(&thermal_zone_mutex);
+		pkgdev->tzone = NULL;
+		mutex_unlock(&thermal_zone_mutex);
+
+		thermal_zone_device_unregister(tzone);
+	}
+
+	/* Protect against work and interrupts */
+	spin_lock_irq(&pkg_temp_lock);
+
+	/*
+	 * Check whether this cpu was the current target and store the new
+	 * one. When we drop the lock, then the interrupt notify function
+	 * will see the new target.
+	 */
+	was_target = pkgdev->cpu == cpu;
+	pkgdev->cpu = target;
+
+	/*
+	 * If this is the last CPU in the package remove the package
+	 * reference from the array and restore the interrupt MSR. When we
+	 * drop the lock neither the interrupt notify function nor the
+	 * worker will see the package anymore.
+	 */
+	if (lastcpu) {
+		packages[topology_logical_package_id(cpu)] = NULL;
+		/* After this point nothing touches the MSR anymore. */
+		wrmsr(MSR_IA32_PACKAGE_THERM_INTERRUPT,
+		      pkgdev->msr_pkg_therm_low, pkgdev->msr_pkg_therm_high);
+	}
+
+	/*
+	 * Check whether there is work scheduled and whether the work is
+	 * targeted at the outgoing CPU.
+	 */
+	if (pkgdev->work_scheduled && was_target) {
+		/*
+		 * To cancel the work we need to drop the lock, otherwise
+		 * we might deadlock if the work needs to be flushed.
+		 */
+		spin_unlock_irq(&pkg_temp_lock);
+		cancel_delayed_work_sync(&pkgdev->work);
+		spin_lock_irq(&pkg_temp_lock);
+		/*
+		 * If this is not the last cpu in the package and the work
+		 * did not run after we dropped the lock above, then we
+		 * need to reschedule the work, otherwise the interrupt
+		 * stays disabled forever.
+		 */
+		if (!lastcpu && pkgdev->work_scheduled)
+			pkg_thermal_schedule_work(target, &pkgdev->work);
+	}
+
+	spin_unlock_irq(&pkg_temp_lock);
+
+	/* Final cleanup if this is the last cpu */
+	if (lastcpu)
+		kfree(pkgdev);
+	return 0;
+}
+
+static int pkg_thermal_cpu_online(unsigned int cpu)
+{
+	struct pkg_device *pkgdev = pkg_temp_thermal_get_dev(cpu);
+	struct cpuinfo_x86 *c = &cpu_data(cpu);
+
+	/* Paranoia check */
+	if (!cpu_has(c, X86_FEATURE_DTHERM) || !cpu_has(c, X86_FEATURE_PTS))
+		return -ENODEV;
+
+	/* If the package exists, nothing to do */
+	if (pkgdev) {
+		cpumask_set_cpu(cpu, &pkgdev->cpumask);
+		return 0;
+	}
+	return pkg_temp_thermal_device_add(cpu);
+}
+
+static const struct x86_cpu_id __initconst pkg_temp_thermal_ids[] = {
+	{ X86_VENDOR_INTEL, X86_FAMILY_ANY, X86_MODEL_ANY, X86_FEATURE_PTS },
+	{}
+};
+MODULE_DEVICE_TABLE(x86cpu, pkg_temp_thermal_ids);
+
+static int __init pkg_temp_thermal_init(void)
+{
+	int ret;
+
+	if (!x86_match_cpu(pkg_temp_thermal_ids))
+		return -ENODEV;
+
+	max_packages = topology_max_packages();
+	packages = kcalloc(max_packages, sizeof(struct pkg_device *),
+			   GFP_KERNEL);
+	if (!packages)
+		return -ENOMEM;
+
+	ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "thermal/x86_pkg:online",
+				pkg_thermal_cpu_online,	pkg_thermal_cpu_offline);
+	if (ret < 0)
+		goto err;
+
+	/* Store the state for module exit */
+	pkg_thermal_hp_state = ret;
+
+	platform_thermal_package_notify = pkg_thermal_notify;
+	platform_thermal_package_rate_control = pkg_thermal_rate_control;
+
+	 /* Don't care if it fails */
+	pkg_temp_debugfs_init();
+	return 0;
+
+err:
+	kfree(packages);
+	return ret;
+}
+module_init(pkg_temp_thermal_init)
+
+static void __exit pkg_temp_thermal_exit(void)
+{
+	platform_thermal_package_notify = NULL;
+	platform_thermal_package_rate_control = NULL;
+
+	cpuhp_remove_state(pkg_thermal_hp_state);
+	debugfs_remove_recursive(debugfs);
+	kfree(packages);
+}
+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");