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/intel_tcc.h>
11 #include <linux/err.h>
12 #include <linux/param.h>
13 #include <linux/device.h>
14 #include <linux/platform_device.h>
15 #include <linux/cpu.h>
16 #include <linux/smp.h>
17 #include <linux/slab.h>
19 #include <linux/thermal.h>
20 #include <linux/debugfs.h>
22 #include <asm/cpu_device_id.h>
24 #include "thermal_interrupt.h"
27 * Rate control delay: Idea is to introduce denounce effect
28 * This should be long enough to avoid reduce events, when
29 * threshold is set to a temperature, which is constantly
30 * violated, but at the short enough to take any action.
31 * The action can be remove threshold or change it to next
32 * interesting setting. Based on experiments, in around
33 * every 5 seconds under load will give us a significant
36 #define PKG_TEMP_THERMAL_NOTIFY_DELAY 5000
37 static int notify_delay_ms = PKG_TEMP_THERMAL_NOTIFY_DELAY;
38 module_param(notify_delay_ms, int, 0644);
39 MODULE_PARM_DESC(notify_delay_ms,
40 "User space notification delay in milli seconds.");
42 /* Number of trip points in thermal zone. Currently it can't
43 * be more than 2. MSR can allow setting and getting notifications
44 * for only 2 thresholds. This define enforces this, if there
45 * is some wrong values returned by cpuid for number of thresholds.
47 #define MAX_NUMBER_OF_TRIPS 2
52 u32 msr_pkg_therm_low;
53 u32 msr_pkg_therm_high;
54 struct delayed_work work;
55 struct thermal_zone_device *tzone;
56 struct cpumask cpumask;
59 static struct thermal_zone_params pkg_temp_tz_params = {
63 /* Keep track of how many zone pointers we allocated in init() */
64 static int max_id __read_mostly;
65 /* Array of zone pointers */
66 static struct zone_device **zones;
67 /* Serializes interrupt notification, work and hotplug */
68 static DEFINE_RAW_SPINLOCK(pkg_temp_lock);
69 /* Protects zone operation in the work function against hotplug removal */
70 static DEFINE_MUTEX(thermal_zone_mutex);
72 /* The dynamically assigned cpu hotplug state for module_exit() */
73 static enum cpuhp_state pkg_thermal_hp_state __read_mostly;
75 /* Debug counters to show using debugfs */
76 static struct dentry *debugfs;
77 static unsigned int pkg_interrupt_cnt;
78 static unsigned int pkg_work_cnt;
80 static void pkg_temp_debugfs_init(void)
82 debugfs = debugfs_create_dir("pkg_temp_thermal", NULL);
84 debugfs_create_u32("pkg_thres_interrupt", S_IRUGO, debugfs,
86 debugfs_create_u32("pkg_thres_work", S_IRUGO, debugfs,
93 * - cpu hotplug: Read serialized by cpu hotplug lock
94 * Write must hold pkg_temp_lock
96 * - Other callsites: Must hold pkg_temp_lock
98 static struct zone_device *pkg_temp_thermal_get_dev(unsigned int cpu)
100 int id = topology_logical_die_id(cpu);
102 if (id >= 0 && id < max_id)
107 static int sys_get_curr_temp(struct thermal_zone_device *tzd, int *temp)
109 struct zone_device *zonedev = thermal_zone_device_priv(tzd);
112 ret = intel_tcc_get_temp(zonedev->cpu, &val, true);
117 pr_debug("sys_get_curr_temp %d\n", *temp);
122 sys_set_trip_temp(struct thermal_zone_device *tzd, int trip, int temp)
124 struct zone_device *zonedev = thermal_zone_device_priv(tzd);
125 u32 l, h, mask, shift, intr;
126 int tj_max, val, ret;
128 tj_max = intel_tcc_get_tjmax(zonedev->cpu);
133 val = (tj_max - temp)/1000;
135 if (trip >= MAX_NUMBER_OF_TRIPS || val < 0 || val > 0x7f)
138 ret = rdmsr_on_cpu(zonedev->cpu, MSR_IA32_PACKAGE_THERM_INTERRUPT,
144 mask = THERM_MASK_THRESHOLD1;
145 shift = THERM_SHIFT_THRESHOLD1;
146 intr = THERM_INT_THRESHOLD1_ENABLE;
148 mask = THERM_MASK_THRESHOLD0;
149 shift = THERM_SHIFT_THRESHOLD0;
150 intr = THERM_INT_THRESHOLD0_ENABLE;
154 * When users space sets a trip temperature == 0, which is indication
155 * that, it is no longer interested in receiving notifications.
164 return wrmsr_on_cpu(zonedev->cpu, MSR_IA32_PACKAGE_THERM_INTERRUPT,
168 /* Thermal zone callback registry */
169 static const struct thermal_zone_device_ops tzone_ops = {
170 .get_temp = sys_get_curr_temp,
171 .set_trip_temp = sys_set_trip_temp,
174 static bool pkg_thermal_rate_control(void)
179 /* Enable threshold interrupt on local package/cpu */
180 static inline void enable_pkg_thres_interrupt(void)
185 rdmsr(MSR_IA32_PACKAGE_THERM_INTERRUPT, l, h);
186 /* only enable/disable if it had valid threshold value */
187 thres_0 = (l & THERM_MASK_THRESHOLD0) >> THERM_SHIFT_THRESHOLD0;
188 thres_1 = (l & THERM_MASK_THRESHOLD1) >> THERM_SHIFT_THRESHOLD1;
190 l |= THERM_INT_THRESHOLD0_ENABLE;
192 l |= THERM_INT_THRESHOLD1_ENABLE;
193 wrmsr(MSR_IA32_PACKAGE_THERM_INTERRUPT, l, h);
196 /* Disable threshold interrupt on local package/cpu */
197 static inline void disable_pkg_thres_interrupt(void)
201 rdmsr(MSR_IA32_PACKAGE_THERM_INTERRUPT, l, h);
203 l &= ~(THERM_INT_THRESHOLD0_ENABLE | THERM_INT_THRESHOLD1_ENABLE);
204 wrmsr(MSR_IA32_PACKAGE_THERM_INTERRUPT, l, h);
207 static void pkg_temp_thermal_threshold_work_fn(struct work_struct *work)
209 struct thermal_zone_device *tzone = NULL;
210 int cpu = smp_processor_id();
211 struct zone_device *zonedev;
213 mutex_lock(&thermal_zone_mutex);
214 raw_spin_lock_irq(&pkg_temp_lock);
217 zonedev = pkg_temp_thermal_get_dev(cpu);
219 raw_spin_unlock_irq(&pkg_temp_lock);
220 mutex_unlock(&thermal_zone_mutex);
223 zonedev->work_scheduled = false;
225 thermal_clear_package_intr_status(PACKAGE_LEVEL, THERM_LOG_THRESHOLD0 | THERM_LOG_THRESHOLD1);
226 tzone = zonedev->tzone;
228 enable_pkg_thres_interrupt();
229 raw_spin_unlock_irq(&pkg_temp_lock);
232 * If tzone is not NULL, then thermal_zone_mutex will prevent the
233 * concurrent removal in the cpu offline callback.
236 thermal_zone_device_update(tzone, THERMAL_EVENT_UNSPECIFIED);
238 mutex_unlock(&thermal_zone_mutex);
241 static void pkg_thermal_schedule_work(int cpu, struct delayed_work *work)
243 unsigned long ms = msecs_to_jiffies(notify_delay_ms);
245 schedule_delayed_work_on(cpu, work, ms);
248 static int pkg_thermal_notify(u64 msr_val)
250 int cpu = smp_processor_id();
251 struct zone_device *zonedev;
254 raw_spin_lock_irqsave(&pkg_temp_lock, flags);
257 disable_pkg_thres_interrupt();
259 /* Work is per package, so scheduling it once is enough. */
260 zonedev = pkg_temp_thermal_get_dev(cpu);
261 if (zonedev && !zonedev->work_scheduled) {
262 zonedev->work_scheduled = true;
263 pkg_thermal_schedule_work(zonedev->cpu, &zonedev->work);
266 raw_spin_unlock_irqrestore(&pkg_temp_lock, flags);
270 static int pkg_temp_thermal_trips_init(int cpu, int tj_max,
271 struct thermal_trip *trips, int num_trips)
273 unsigned long thres_reg_value;
274 u32 mask, shift, eax, edx;
277 for (i = 0; i < num_trips; i++) {
280 mask = THERM_MASK_THRESHOLD1;
281 shift = THERM_SHIFT_THRESHOLD1;
283 mask = THERM_MASK_THRESHOLD0;
284 shift = THERM_SHIFT_THRESHOLD0;
287 ret = rdmsr_on_cpu(cpu, MSR_IA32_PACKAGE_THERM_INTERRUPT,
292 thres_reg_value = (eax & mask) >> shift;
294 trips[i].temperature = thres_reg_value ?
295 tj_max - thres_reg_value * 1000 : THERMAL_TEMP_INVALID;
297 trips[i].type = THERMAL_TRIP_PASSIVE;
298 trips[i].flags |= THERMAL_TRIP_FLAG_RW_TEMP;
300 pr_debug("%s: cpu=%d, trip=%d, temp=%d\n",
301 __func__, cpu, i, trips[i].temperature);
307 static int pkg_temp_thermal_device_add(unsigned int cpu)
309 struct thermal_trip trips[MAX_NUMBER_OF_TRIPS] = { 0 };
310 int id = topology_logical_die_id(cpu);
311 u32 eax, ebx, ecx, edx;
312 struct zone_device *zonedev;
313 int thres_count, err;
319 cpuid(6, &eax, &ebx, &ecx, &edx);
320 thres_count = ebx & 0x07;
324 thres_count = clamp_val(thres_count, 0, MAX_NUMBER_OF_TRIPS);
326 tj_max = intel_tcc_get_tjmax(cpu);
330 zonedev = kzalloc(sizeof(*zonedev), GFP_KERNEL);
334 err = pkg_temp_thermal_trips_init(cpu, tj_max, trips, thres_count);
336 goto out_kfree_zonedev;
338 INIT_DELAYED_WORK(&zonedev->work, pkg_temp_thermal_threshold_work_fn);
340 zonedev->tzone = thermal_zone_device_register_with_trips("x86_pkg_temp",
342 zonedev, &tzone_ops, &pkg_temp_tz_params, 0, 0);
343 if (IS_ERR(zonedev->tzone)) {
344 err = PTR_ERR(zonedev->tzone);
345 goto out_kfree_zonedev;
347 err = thermal_zone_device_enable(zonedev->tzone);
349 goto out_unregister_tz;
351 /* Store MSR value for package thermal interrupt, to restore at exit */
352 rdmsr(MSR_IA32_PACKAGE_THERM_INTERRUPT, zonedev->msr_pkg_therm_low,
353 zonedev->msr_pkg_therm_high);
355 cpumask_set_cpu(cpu, &zonedev->cpumask);
356 raw_spin_lock_irq(&pkg_temp_lock);
358 raw_spin_unlock_irq(&pkg_temp_lock);
363 thermal_zone_device_unregister(zonedev->tzone);
369 static int pkg_thermal_cpu_offline(unsigned int cpu)
371 struct zone_device *zonedev = pkg_temp_thermal_get_dev(cpu);
372 bool lastcpu, was_target;
378 target = cpumask_any_but(&zonedev->cpumask, cpu);
379 cpumask_clear_cpu(cpu, &zonedev->cpumask);
380 lastcpu = target >= nr_cpu_ids;
382 * Remove the sysfs files, if this is the last cpu in the package
383 * before doing further cleanups.
386 struct thermal_zone_device *tzone = zonedev->tzone;
389 * We must protect against a work function calling
390 * thermal_zone_update, after/while unregister. We null out
391 * the pointer under the zone mutex, so the worker function
394 mutex_lock(&thermal_zone_mutex);
395 zonedev->tzone = NULL;
396 mutex_unlock(&thermal_zone_mutex);
398 thermal_zone_device_unregister(tzone);
401 /* Protect against work and interrupts */
402 raw_spin_lock_irq(&pkg_temp_lock);
405 * Check whether this cpu was the current target and store the new
406 * one. When we drop the lock, then the interrupt notify function
407 * will see the new target.
409 was_target = zonedev->cpu == cpu;
410 zonedev->cpu = target;
413 * If this is the last CPU in the package remove the package
414 * reference from the array and restore the interrupt MSR. When we
415 * drop the lock neither the interrupt notify function nor the
416 * worker will see the package anymore.
419 zones[topology_logical_die_id(cpu)] = NULL;
420 /* After this point nothing touches the MSR anymore. */
421 wrmsr(MSR_IA32_PACKAGE_THERM_INTERRUPT,
422 zonedev->msr_pkg_therm_low, zonedev->msr_pkg_therm_high);
426 * Check whether there is work scheduled and whether the work is
427 * targeted at the outgoing CPU.
429 if (zonedev->work_scheduled && was_target) {
431 * To cancel the work we need to drop the lock, otherwise
432 * we might deadlock if the work needs to be flushed.
434 raw_spin_unlock_irq(&pkg_temp_lock);
435 cancel_delayed_work_sync(&zonedev->work);
436 raw_spin_lock_irq(&pkg_temp_lock);
438 * If this is not the last cpu in the package and the work
439 * did not run after we dropped the lock above, then we
440 * need to reschedule the work, otherwise the interrupt
441 * stays disabled forever.
443 if (!lastcpu && zonedev->work_scheduled)
444 pkg_thermal_schedule_work(target, &zonedev->work);
447 raw_spin_unlock_irq(&pkg_temp_lock);
449 /* Final cleanup if this is the last cpu */
456 static int pkg_thermal_cpu_online(unsigned int cpu)
458 struct zone_device *zonedev = pkg_temp_thermal_get_dev(cpu);
459 struct cpuinfo_x86 *c = &cpu_data(cpu);
462 if (!cpu_has(c, X86_FEATURE_DTHERM) || !cpu_has(c, X86_FEATURE_PTS))
465 /* If the package exists, nothing to do */
467 cpumask_set_cpu(cpu, &zonedev->cpumask);
470 return pkg_temp_thermal_device_add(cpu);
473 static const struct x86_cpu_id __initconst pkg_temp_thermal_ids[] = {
474 X86_MATCH_VENDOR_FEATURE(INTEL, X86_FEATURE_PTS, NULL),
477 MODULE_DEVICE_TABLE(x86cpu, pkg_temp_thermal_ids);
479 static int __init pkg_temp_thermal_init(void)
483 if (!x86_match_cpu(pkg_temp_thermal_ids))
486 max_id = topology_max_packages() * topology_max_dies_per_package();
487 zones = kcalloc(max_id, sizeof(struct zone_device *),
492 ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "thermal/x86_pkg:online",
493 pkg_thermal_cpu_online, pkg_thermal_cpu_offline);
497 /* Store the state for module exit */
498 pkg_thermal_hp_state = ret;
500 platform_thermal_package_notify = pkg_thermal_notify;
501 platform_thermal_package_rate_control = pkg_thermal_rate_control;
503 /* Don't care if it fails */
504 pkg_temp_debugfs_init();
511 module_init(pkg_temp_thermal_init)
513 static void __exit pkg_temp_thermal_exit(void)
515 platform_thermal_package_notify = NULL;
516 platform_thermal_package_rate_control = NULL;
518 cpuhp_remove_state(pkg_thermal_hp_state);
519 debugfs_remove_recursive(debugfs);
522 module_exit(pkg_temp_thermal_exit)
524 MODULE_IMPORT_NS(INTEL_TCC);
525 MODULE_DESCRIPTION("X86 PKG TEMP Thermal Driver");
526 MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");
527 MODULE_LICENSE("GPL v2");