1 // SPDX-License-Identifier: GPL-2.0-only
3 * x86_pkg_temp_thermal driver
4 * Copyright (c) 2013, Intel Corporation.
6 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
8 #include <linux/module.h>
9 #include <linux/init.h>
10 #include <linux/err.h>
11 #include <linux/param.h>
12 #include <linux/device.h>
13 #include <linux/platform_device.h>
14 #include <linux/cpu.h>
15 #include <linux/smp.h>
16 #include <linux/slab.h>
18 #include <linux/thermal.h>
19 #include <linux/debugfs.h>
20 #include <asm/cpu_device_id.h>
24 * Rate control delay: Idea is to introduce denounce effect
25 * This should be long enough to avoid reduce events, when
26 * threshold is set to a temperature, which is constantly
27 * violated, but at the short enough to take any action.
28 * The action can be remove threshold or change it to next
29 * interesting setting. Based on experiments, in around
30 * every 5 seconds under load will give us a significant
33 #define PKG_TEMP_THERMAL_NOTIFY_DELAY 5000
34 static int notify_delay_ms = PKG_TEMP_THERMAL_NOTIFY_DELAY;
35 module_param(notify_delay_ms, int, 0644);
36 MODULE_PARM_DESC(notify_delay_ms,
37 "User space notification delay in milli seconds.");
39 /* Number of trip points in thermal zone. Currently it can't
40 * be more than 2. MSR can allow setting and getting notifications
41 * for only 2 thresholds. This define enforces this, if there
42 * is some wrong values returned by cpuid for number of thresholds.
44 #define MAX_NUMBER_OF_TRIPS 2
50 u32 msr_pkg_therm_low;
51 u32 msr_pkg_therm_high;
52 struct delayed_work work;
53 struct thermal_zone_device *tzone;
54 struct cpumask cpumask;
57 static struct thermal_zone_params pkg_temp_tz_params = {
61 /* Keep track of how many zone pointers we allocated in init() */
62 static int max_id __read_mostly;
63 /* Array of zone pointers */
64 static struct zone_device **zones;
65 /* Serializes interrupt notification, work and hotplug */
66 static DEFINE_SPINLOCK(pkg_temp_lock);
67 /* Protects zone operation in the work function against hotplug removal */
68 static DEFINE_MUTEX(thermal_zone_mutex);
70 /* The dynamically assigned cpu hotplug state for module_exit() */
71 static enum cpuhp_state pkg_thermal_hp_state __read_mostly;
73 /* Debug counters to show using debugfs */
74 static struct dentry *debugfs;
75 static unsigned int pkg_interrupt_cnt;
76 static unsigned int pkg_work_cnt;
78 static int pkg_temp_debugfs_init(void)
82 debugfs = debugfs_create_dir("pkg_temp_thermal", NULL);
86 d = debugfs_create_u32("pkg_thres_interrupt", S_IRUGO, debugfs,
91 d = debugfs_create_u32("pkg_thres_work", S_IRUGO, debugfs,
99 debugfs_remove_recursive(debugfs);
106 * - cpu hotplug: Read serialized by cpu hotplug lock
107 * Write must hold pkg_temp_lock
109 * - Other callsites: Must hold pkg_temp_lock
111 static struct zone_device *pkg_temp_thermal_get_dev(unsigned int cpu)
113 int id = topology_logical_die_id(cpu);
115 if (id >= 0 && id < max_id)
121 * tj-max is is interesting because threshold is set relative to this
124 static int get_tj_max(int cpu, u32 *tj_max)
129 err = rdmsr_safe_on_cpu(cpu, MSR_IA32_TEMPERATURE_TARGET, &eax, &edx);
133 val = (eax >> 16) & 0xff;
134 *tj_max = val * 1000;
136 return val ? 0 : -EINVAL;
139 static int sys_get_curr_temp(struct thermal_zone_device *tzd, int *temp)
141 struct zone_device *zonedev = tzd->devdata;
144 rdmsr_on_cpu(zonedev->cpu, MSR_IA32_PACKAGE_THERM_STATUS,
146 if (eax & 0x80000000) {
147 *temp = zonedev->tj_max - ((eax >> 16) & 0x7f) * 1000;
148 pr_debug("sys_get_curr_temp %d\n", *temp);
154 static int sys_get_trip_temp(struct thermal_zone_device *tzd,
157 struct zone_device *zonedev = tzd->devdata;
158 unsigned long thres_reg_value;
159 u32 mask, shift, eax, edx;
162 if (trip >= MAX_NUMBER_OF_TRIPS)
166 mask = THERM_MASK_THRESHOLD1;
167 shift = THERM_SHIFT_THRESHOLD1;
169 mask = THERM_MASK_THRESHOLD0;
170 shift = THERM_SHIFT_THRESHOLD0;
173 ret = rdmsr_on_cpu(zonedev->cpu, MSR_IA32_PACKAGE_THERM_INTERRUPT,
178 thres_reg_value = (eax & mask) >> shift;
180 *temp = zonedev->tj_max - thres_reg_value * 1000;
183 pr_debug("sys_get_trip_temp %d\n", *temp);
189 sys_set_trip_temp(struct thermal_zone_device *tzd, int trip, int temp)
191 struct zone_device *zonedev = tzd->devdata;
192 u32 l, h, mask, shift, intr;
195 if (trip >= MAX_NUMBER_OF_TRIPS || temp >= zonedev->tj_max)
198 ret = rdmsr_on_cpu(zonedev->cpu, MSR_IA32_PACKAGE_THERM_INTERRUPT,
204 mask = THERM_MASK_THRESHOLD1;
205 shift = THERM_SHIFT_THRESHOLD1;
206 intr = THERM_INT_THRESHOLD1_ENABLE;
208 mask = THERM_MASK_THRESHOLD0;
209 shift = THERM_SHIFT_THRESHOLD0;
210 intr = THERM_INT_THRESHOLD0_ENABLE;
214 * When users space sets a trip temperature == 0, which is indication
215 * that, it is no longer interested in receiving notifications.
220 l |= (zonedev->tj_max - temp)/1000 << shift;
224 return wrmsr_on_cpu(zonedev->cpu, MSR_IA32_PACKAGE_THERM_INTERRUPT,
228 static int sys_get_trip_type(struct thermal_zone_device *thermal, int trip,
229 enum thermal_trip_type *type)
231 *type = THERMAL_TRIP_PASSIVE;
235 /* Thermal zone callback registry */
236 static struct thermal_zone_device_ops tzone_ops = {
237 .get_temp = sys_get_curr_temp,
238 .get_trip_temp = sys_get_trip_temp,
239 .get_trip_type = sys_get_trip_type,
240 .set_trip_temp = sys_set_trip_temp,
243 static bool pkg_thermal_rate_control(void)
248 /* Enable threshold interrupt on local package/cpu */
249 static inline void enable_pkg_thres_interrupt(void)
254 rdmsr(MSR_IA32_PACKAGE_THERM_INTERRUPT, l, h);
255 /* only enable/disable if it had valid threshold value */
256 thres_0 = (l & THERM_MASK_THRESHOLD0) >> THERM_SHIFT_THRESHOLD0;
257 thres_1 = (l & THERM_MASK_THRESHOLD1) >> THERM_SHIFT_THRESHOLD1;
259 l |= THERM_INT_THRESHOLD0_ENABLE;
261 l |= THERM_INT_THRESHOLD1_ENABLE;
262 wrmsr(MSR_IA32_PACKAGE_THERM_INTERRUPT, l, h);
265 /* Disable threshold interrupt on local package/cpu */
266 static inline void disable_pkg_thres_interrupt(void)
270 rdmsr(MSR_IA32_PACKAGE_THERM_INTERRUPT, l, h);
272 l &= ~(THERM_INT_THRESHOLD0_ENABLE | THERM_INT_THRESHOLD1_ENABLE);
273 wrmsr(MSR_IA32_PACKAGE_THERM_INTERRUPT, l, h);
276 static void pkg_temp_thermal_threshold_work_fn(struct work_struct *work)
278 struct thermal_zone_device *tzone = NULL;
279 int cpu = smp_processor_id();
280 struct zone_device *zonedev;
283 mutex_lock(&thermal_zone_mutex);
284 spin_lock_irq(&pkg_temp_lock);
287 zonedev = pkg_temp_thermal_get_dev(cpu);
289 spin_unlock_irq(&pkg_temp_lock);
290 mutex_unlock(&thermal_zone_mutex);
293 zonedev->work_scheduled = false;
295 rdmsrl(MSR_IA32_PACKAGE_THERM_STATUS, msr_val);
296 wr_val = msr_val & ~(THERM_LOG_THRESHOLD0 | THERM_LOG_THRESHOLD1);
297 if (wr_val != msr_val) {
298 wrmsrl(MSR_IA32_PACKAGE_THERM_STATUS, wr_val);
299 tzone = zonedev->tzone;
302 enable_pkg_thres_interrupt();
303 spin_unlock_irq(&pkg_temp_lock);
306 * If tzone is not NULL, then thermal_zone_mutex will prevent the
307 * concurrent removal in the cpu offline callback.
310 thermal_zone_device_update(tzone, THERMAL_EVENT_UNSPECIFIED);
312 mutex_unlock(&thermal_zone_mutex);
315 static void pkg_thermal_schedule_work(int cpu, struct delayed_work *work)
317 unsigned long ms = msecs_to_jiffies(notify_delay_ms);
319 schedule_delayed_work_on(cpu, work, ms);
322 static int pkg_thermal_notify(u64 msr_val)
324 int cpu = smp_processor_id();
325 struct zone_device *zonedev;
328 spin_lock_irqsave(&pkg_temp_lock, flags);
331 disable_pkg_thres_interrupt();
333 /* Work is per package, so scheduling it once is enough. */
334 zonedev = pkg_temp_thermal_get_dev(cpu);
335 if (zonedev && !zonedev->work_scheduled) {
336 zonedev->work_scheduled = true;
337 pkg_thermal_schedule_work(zonedev->cpu, &zonedev->work);
340 spin_unlock_irqrestore(&pkg_temp_lock, flags);
344 static int pkg_temp_thermal_device_add(unsigned int cpu)
346 int id = topology_logical_die_id(cpu);
347 u32 tj_max, eax, ebx, ecx, edx;
348 struct zone_device *zonedev;
349 int thres_count, err;
354 cpuid(6, &eax, &ebx, &ecx, &edx);
355 thres_count = ebx & 0x07;
359 thres_count = clamp_val(thres_count, 0, MAX_NUMBER_OF_TRIPS);
361 err = get_tj_max(cpu, &tj_max);
365 zonedev = kzalloc(sizeof(*zonedev), GFP_KERNEL);
369 INIT_DELAYED_WORK(&zonedev->work, pkg_temp_thermal_threshold_work_fn);
371 zonedev->tj_max = tj_max;
372 zonedev->tzone = thermal_zone_device_register("x86_pkg_temp",
374 (thres_count == MAX_NUMBER_OF_TRIPS) ? 0x03 : 0x01,
375 zonedev, &tzone_ops, &pkg_temp_tz_params, 0, 0);
376 if (IS_ERR(zonedev->tzone)) {
377 err = PTR_ERR(zonedev->tzone);
381 /* Store MSR value for package thermal interrupt, to restore at exit */
382 rdmsr(MSR_IA32_PACKAGE_THERM_INTERRUPT, zonedev->msr_pkg_therm_low,
383 zonedev->msr_pkg_therm_high);
385 cpumask_set_cpu(cpu, &zonedev->cpumask);
386 spin_lock_irq(&pkg_temp_lock);
388 spin_unlock_irq(&pkg_temp_lock);
392 static int pkg_thermal_cpu_offline(unsigned int cpu)
394 struct zone_device *zonedev = pkg_temp_thermal_get_dev(cpu);
395 bool lastcpu, was_target;
401 target = cpumask_any_but(&zonedev->cpumask, cpu);
402 cpumask_clear_cpu(cpu, &zonedev->cpumask);
403 lastcpu = target >= nr_cpu_ids;
405 * Remove the sysfs files, if this is the last cpu in the package
406 * before doing further cleanups.
409 struct thermal_zone_device *tzone = zonedev->tzone;
412 * We must protect against a work function calling
413 * thermal_zone_update, after/while unregister. We null out
414 * the pointer under the zone mutex, so the worker function
417 mutex_lock(&thermal_zone_mutex);
418 zonedev->tzone = NULL;
419 mutex_unlock(&thermal_zone_mutex);
421 thermal_zone_device_unregister(tzone);
424 /* Protect against work and interrupts */
425 spin_lock_irq(&pkg_temp_lock);
428 * Check whether this cpu was the current target and store the new
429 * one. When we drop the lock, then the interrupt notify function
430 * will see the new target.
432 was_target = zonedev->cpu == cpu;
433 zonedev->cpu = target;
436 * If this is the last CPU in the package remove the package
437 * reference from the array and restore the interrupt MSR. When we
438 * drop the lock neither the interrupt notify function nor the
439 * worker will see the package anymore.
442 zones[topology_logical_die_id(cpu)] = NULL;
443 /* After this point nothing touches the MSR anymore. */
444 wrmsr(MSR_IA32_PACKAGE_THERM_INTERRUPT,
445 zonedev->msr_pkg_therm_low, zonedev->msr_pkg_therm_high);
449 * Check whether there is work scheduled and whether the work is
450 * targeted at the outgoing CPU.
452 if (zonedev->work_scheduled && was_target) {
454 * To cancel the work we need to drop the lock, otherwise
455 * we might deadlock if the work needs to be flushed.
457 spin_unlock_irq(&pkg_temp_lock);
458 cancel_delayed_work_sync(&zonedev->work);
459 spin_lock_irq(&pkg_temp_lock);
461 * If this is not the last cpu in the package and the work
462 * did not run after we dropped the lock above, then we
463 * need to reschedule the work, otherwise the interrupt
464 * stays disabled forever.
466 if (!lastcpu && zonedev->work_scheduled)
467 pkg_thermal_schedule_work(target, &zonedev->work);
470 spin_unlock_irq(&pkg_temp_lock);
472 /* Final cleanup if this is the last cpu */
478 static int pkg_thermal_cpu_online(unsigned int cpu)
480 struct zone_device *zonedev = pkg_temp_thermal_get_dev(cpu);
481 struct cpuinfo_x86 *c = &cpu_data(cpu);
484 if (!cpu_has(c, X86_FEATURE_DTHERM) || !cpu_has(c, X86_FEATURE_PTS))
487 /* If the package exists, nothing to do */
489 cpumask_set_cpu(cpu, &zonedev->cpumask);
492 return pkg_temp_thermal_device_add(cpu);
495 static const struct x86_cpu_id __initconst pkg_temp_thermal_ids[] = {
496 { X86_VENDOR_INTEL, X86_FAMILY_ANY, X86_MODEL_ANY, X86_FEATURE_PTS },
499 MODULE_DEVICE_TABLE(x86cpu, pkg_temp_thermal_ids);
501 static int __init pkg_temp_thermal_init(void)
505 if (!x86_match_cpu(pkg_temp_thermal_ids))
508 max_id = topology_max_packages() * topology_max_die_per_package();
509 zones = kcalloc(max_id, sizeof(struct zone_device *),
514 ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "thermal/x86_pkg:online",
515 pkg_thermal_cpu_online, pkg_thermal_cpu_offline);
519 /* Store the state for module exit */
520 pkg_thermal_hp_state = ret;
522 platform_thermal_package_notify = pkg_thermal_notify;
523 platform_thermal_package_rate_control = pkg_thermal_rate_control;
525 /* Don't care if it fails */
526 pkg_temp_debugfs_init();
533 module_init(pkg_temp_thermal_init)
535 static void __exit pkg_temp_thermal_exit(void)
537 platform_thermal_package_notify = NULL;
538 platform_thermal_package_rate_control = NULL;
540 cpuhp_remove_state(pkg_thermal_hp_state);
541 debugfs_remove_recursive(debugfs);
544 module_exit(pkg_temp_thermal_exit)
546 MODULE_DESCRIPTION("X86 PKG TEMP Thermal Driver");
547 MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");
548 MODULE_LICENSE("GPL v2");