2 * x86_pkg_temp_thermal driver
3 * Copyright (c) 2013, Intel Corporation.
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms and conditions of the GNU General Public License,
7 * version 2, as published by the Free Software Foundation.
9 * This program is distributed in the hope it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
14 * You should have received a copy of the GNU General Public License along with
15 * this program; if not, write to the Free Software Foundation, Inc.
18 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
20 #include <linux/module.h>
21 #include <linux/init.h>
22 #include <linux/err.h>
23 #include <linux/param.h>
24 #include <linux/device.h>
25 #include <linux/platform_device.h>
26 #include <linux/cpu.h>
27 #include <linux/smp.h>
28 #include <linux/slab.h>
30 #include <linux/thermal.h>
31 #include <linux/debugfs.h>
32 #include <asm/cpu_device_id.h>
36 * Rate control delay: Idea is to introduce denounce effect
37 * This should be long enough to avoid reduce events, when
38 * threshold is set to a temperature, which is constantly
39 * violated, but at the short enough to take any action.
40 * The action can be remove threshold or change it to next
41 * interesting setting. Based on experiments, in around
42 * every 5 seconds under load will give us a significant
45 #define PKG_TEMP_THERMAL_NOTIFY_DELAY 5000
46 static int notify_delay_ms
= PKG_TEMP_THERMAL_NOTIFY_DELAY
;
47 module_param(notify_delay_ms
, int, 0644);
48 MODULE_PARM_DESC(notify_delay_ms
,
49 "User space notification delay in milli seconds.");
51 /* Number of trip points in thermal zone. Currently it can't
52 * be more than 2. MSR can allow setting and getting notifications
53 * for only 2 thresholds. This define enforces this, if there
54 * is some wrong values returned by cpuid for number of thresholds.
56 #define MAX_NUMBER_OF_TRIPS 2
62 u32 msr_pkg_therm_low
;
63 u32 msr_pkg_therm_high
;
64 struct delayed_work work
;
65 struct thermal_zone_device
*tzone
;
66 struct cpumask cpumask
;
69 static struct thermal_zone_params pkg_temp_tz_params
= {
73 /* Keep track of how many package pointers we allocated in init() */
74 static int max_packages __read_mostly
;
75 /* Array of package pointers */
76 static struct pkg_device
**packages
;
77 /* Serializes interrupt notification, work and hotplug */
78 static DEFINE_SPINLOCK(pkg_temp_lock
);
79 /* Protects zone operation in the work function against hotplug removal */
80 static DEFINE_MUTEX(thermal_zone_mutex
);
82 /* The dynamically assigned cpu hotplug state for module_exit() */
83 static enum cpuhp_state pkg_thermal_hp_state __read_mostly
;
85 /* Debug counters to show using debugfs */
86 static struct dentry
*debugfs
;
87 static unsigned int pkg_interrupt_cnt
;
88 static unsigned int pkg_work_cnt
;
90 static int pkg_temp_debugfs_init(void)
94 debugfs
= debugfs_create_dir("pkg_temp_thermal", NULL
);
98 d
= debugfs_create_u32("pkg_thres_interrupt", S_IRUGO
, debugfs
,
99 (u32
*)&pkg_interrupt_cnt
);
103 d
= debugfs_create_u32("pkg_thres_work", S_IRUGO
, debugfs
,
104 (u32
*)&pkg_work_cnt
);
111 debugfs_remove_recursive(debugfs
);
118 * - cpu hotplug: Read serialized by cpu hotplug lock
119 * Write must hold pkg_temp_lock
121 * - Other callsites: Must hold pkg_temp_lock
123 static struct pkg_device
*pkg_temp_thermal_get_dev(unsigned int cpu
)
125 int pkgid
= topology_logical_package_id(cpu
);
127 if (pkgid
>= 0 && pkgid
< max_packages
)
128 return packages
[pkgid
];
133 * tj-max is is interesting because threshold is set relative to this
136 static int get_tj_max(int cpu
, u32
*tj_max
)
141 err
= rdmsr_safe_on_cpu(cpu
, MSR_IA32_TEMPERATURE_TARGET
, &eax
, &edx
);
145 val
= (eax
>> 16) & 0xff;
146 *tj_max
= val
* 1000;
148 return val
? 0 : -EINVAL
;
151 static int sys_get_curr_temp(struct thermal_zone_device
*tzd
, int *temp
)
153 struct pkg_device
*pkgdev
= tzd
->devdata
;
156 rdmsr_on_cpu(pkgdev
->cpu
, MSR_IA32_PACKAGE_THERM_STATUS
, &eax
, &edx
);
157 if (eax
& 0x80000000) {
158 *temp
= pkgdev
->tj_max
- ((eax
>> 16) & 0x7f) * 1000;
159 pr_debug("sys_get_curr_temp %d\n", *temp
);
165 static int sys_get_trip_temp(struct thermal_zone_device
*tzd
,
168 struct pkg_device
*pkgdev
= tzd
->devdata
;
169 unsigned long thres_reg_value
;
170 u32 mask
, shift
, eax
, edx
;
173 if (trip
>= MAX_NUMBER_OF_TRIPS
)
177 mask
= THERM_MASK_THRESHOLD1
;
178 shift
= THERM_SHIFT_THRESHOLD1
;
180 mask
= THERM_MASK_THRESHOLD0
;
181 shift
= THERM_SHIFT_THRESHOLD0
;
184 ret
= rdmsr_on_cpu(pkgdev
->cpu
, MSR_IA32_PACKAGE_THERM_INTERRUPT
,
189 thres_reg_value
= (eax
& mask
) >> shift
;
191 *temp
= pkgdev
->tj_max
- thres_reg_value
* 1000;
194 pr_debug("sys_get_trip_temp %d\n", *temp
);
200 sys_set_trip_temp(struct thermal_zone_device
*tzd
, int trip
, int temp
)
202 struct pkg_device
*pkgdev
= tzd
->devdata
;
203 u32 l
, h
, mask
, shift
, intr
;
206 if (trip
>= MAX_NUMBER_OF_TRIPS
|| temp
>= pkgdev
->tj_max
)
209 ret
= rdmsr_on_cpu(pkgdev
->cpu
, MSR_IA32_PACKAGE_THERM_INTERRUPT
,
215 mask
= THERM_MASK_THRESHOLD1
;
216 shift
= THERM_SHIFT_THRESHOLD1
;
217 intr
= THERM_INT_THRESHOLD1_ENABLE
;
219 mask
= THERM_MASK_THRESHOLD0
;
220 shift
= THERM_SHIFT_THRESHOLD0
;
221 intr
= THERM_INT_THRESHOLD0_ENABLE
;
225 * When users space sets a trip temperature == 0, which is indication
226 * that, it is no longer interested in receiving notifications.
231 l
|= (pkgdev
->tj_max
- temp
)/1000 << shift
;
235 return wrmsr_on_cpu(pkgdev
->cpu
, MSR_IA32_PACKAGE_THERM_INTERRUPT
, l
, h
);
238 static int sys_get_trip_type(struct thermal_zone_device
*thermal
, int trip
,
239 enum thermal_trip_type
*type
)
241 *type
= THERMAL_TRIP_PASSIVE
;
245 /* Thermal zone callback registry */
246 static struct thermal_zone_device_ops tzone_ops
= {
247 .get_temp
= sys_get_curr_temp
,
248 .get_trip_temp
= sys_get_trip_temp
,
249 .get_trip_type
= sys_get_trip_type
,
250 .set_trip_temp
= sys_set_trip_temp
,
253 static bool pkg_thermal_rate_control(void)
258 /* Enable threshold interrupt on local package/cpu */
259 static inline void enable_pkg_thres_interrupt(void)
264 rdmsr(MSR_IA32_PACKAGE_THERM_INTERRUPT
, l
, h
);
265 /* only enable/disable if it had valid threshold value */
266 thres_0
= (l
& THERM_MASK_THRESHOLD0
) >> THERM_SHIFT_THRESHOLD0
;
267 thres_1
= (l
& THERM_MASK_THRESHOLD1
) >> THERM_SHIFT_THRESHOLD1
;
269 l
|= THERM_INT_THRESHOLD0_ENABLE
;
271 l
|= THERM_INT_THRESHOLD1_ENABLE
;
272 wrmsr(MSR_IA32_PACKAGE_THERM_INTERRUPT
, l
, h
);
275 /* Disable threshold interrupt on local package/cpu */
276 static inline void disable_pkg_thres_interrupt(void)
280 rdmsr(MSR_IA32_PACKAGE_THERM_INTERRUPT
, l
, h
);
282 l
&= ~(THERM_INT_THRESHOLD0_ENABLE
| THERM_INT_THRESHOLD1_ENABLE
);
283 wrmsr(MSR_IA32_PACKAGE_THERM_INTERRUPT
, l
, h
);
286 static void pkg_temp_thermal_threshold_work_fn(struct work_struct
*work
)
288 struct thermal_zone_device
*tzone
= NULL
;
289 int cpu
= smp_processor_id();
290 struct pkg_device
*pkgdev
;
293 mutex_lock(&thermal_zone_mutex
);
294 spin_lock_irq(&pkg_temp_lock
);
297 pkgdev
= pkg_temp_thermal_get_dev(cpu
);
299 spin_unlock_irq(&pkg_temp_lock
);
300 mutex_unlock(&thermal_zone_mutex
);
303 pkgdev
->work_scheduled
= false;
305 rdmsrl(MSR_IA32_PACKAGE_THERM_STATUS
, msr_val
);
306 wr_val
= msr_val
& ~(THERM_LOG_THRESHOLD0
| THERM_LOG_THRESHOLD1
);
307 if (wr_val
!= msr_val
) {
308 wrmsrl(MSR_IA32_PACKAGE_THERM_STATUS
, wr_val
);
309 tzone
= pkgdev
->tzone
;
312 enable_pkg_thres_interrupt();
313 spin_unlock_irq(&pkg_temp_lock
);
316 * If tzone is not NULL, then thermal_zone_mutex will prevent the
317 * concurrent removal in the cpu offline callback.
320 thermal_zone_device_update(tzone
, THERMAL_EVENT_UNSPECIFIED
);
322 mutex_unlock(&thermal_zone_mutex
);
325 static void pkg_thermal_schedule_work(int cpu
, struct delayed_work
*work
)
327 unsigned long ms
= msecs_to_jiffies(notify_delay_ms
);
329 schedule_delayed_work_on(cpu
, work
, ms
);
332 static int pkg_thermal_notify(u64 msr_val
)
334 int cpu
= smp_processor_id();
335 struct pkg_device
*pkgdev
;
338 spin_lock_irqsave(&pkg_temp_lock
, flags
);
341 disable_pkg_thres_interrupt();
343 /* Work is per package, so scheduling it once is enough. */
344 pkgdev
= pkg_temp_thermal_get_dev(cpu
);
345 if (pkgdev
&& !pkgdev
->work_scheduled
) {
346 pkgdev
->work_scheduled
= true;
347 pkg_thermal_schedule_work(pkgdev
->cpu
, &pkgdev
->work
);
350 spin_unlock_irqrestore(&pkg_temp_lock
, flags
);
354 static int pkg_temp_thermal_device_add(unsigned int cpu
)
356 int pkgid
= topology_logical_package_id(cpu
);
357 u32 tj_max
, eax
, ebx
, ecx
, edx
;
358 struct pkg_device
*pkgdev
;
359 int thres_count
, err
;
361 if (pkgid
>= max_packages
)
364 cpuid(6, &eax
, &ebx
, &ecx
, &edx
);
365 thres_count
= ebx
& 0x07;
369 thres_count
= clamp_val(thres_count
, 0, MAX_NUMBER_OF_TRIPS
);
371 err
= get_tj_max(cpu
, &tj_max
);
375 pkgdev
= kzalloc(sizeof(*pkgdev
), GFP_KERNEL
);
379 INIT_DELAYED_WORK(&pkgdev
->work
, pkg_temp_thermal_threshold_work_fn
);
381 pkgdev
->tj_max
= tj_max
;
382 pkgdev
->tzone
= thermal_zone_device_register("x86_pkg_temp",
384 (thres_count
== MAX_NUMBER_OF_TRIPS
) ? 0x03 : 0x01,
385 pkgdev
, &tzone_ops
, &pkg_temp_tz_params
, 0, 0);
386 if (IS_ERR(pkgdev
->tzone
)) {
387 err
= PTR_ERR(pkgdev
->tzone
);
391 /* Store MSR value for package thermal interrupt, to restore at exit */
392 rdmsr(MSR_IA32_PACKAGE_THERM_INTERRUPT
, pkgdev
->msr_pkg_therm_low
,
393 pkgdev
->msr_pkg_therm_high
);
395 cpumask_set_cpu(cpu
, &pkgdev
->cpumask
);
396 spin_lock_irq(&pkg_temp_lock
);
397 packages
[pkgid
] = pkgdev
;
398 spin_unlock_irq(&pkg_temp_lock
);
402 static int pkg_thermal_cpu_offline(unsigned int cpu
)
404 struct pkg_device
*pkgdev
= pkg_temp_thermal_get_dev(cpu
);
405 bool lastcpu
, was_target
;
411 target
= cpumask_any_but(&pkgdev
->cpumask
, cpu
);
412 cpumask_clear_cpu(cpu
, &pkgdev
->cpumask
);
413 lastcpu
= target
>= nr_cpu_ids
;
415 * Remove the sysfs files, if this is the last cpu in the package
416 * before doing further cleanups.
419 struct thermal_zone_device
*tzone
= pkgdev
->tzone
;
422 * We must protect against a work function calling
423 * thermal_zone_update, after/while unregister. We null out
424 * the pointer under the zone mutex, so the worker function
427 mutex_lock(&thermal_zone_mutex
);
428 pkgdev
->tzone
= NULL
;
429 mutex_unlock(&thermal_zone_mutex
);
431 thermal_zone_device_unregister(tzone
);
434 /* Protect against work and interrupts */
435 spin_lock_irq(&pkg_temp_lock
);
438 * Check whether this cpu was the current target and store the new
439 * one. When we drop the lock, then the interrupt notify function
440 * will see the new target.
442 was_target
= pkgdev
->cpu
== cpu
;
443 pkgdev
->cpu
= target
;
446 * If this is the last CPU in the package remove the package
447 * reference from the array and restore the interrupt MSR. When we
448 * drop the lock neither the interrupt notify function nor the
449 * worker will see the package anymore.
452 packages
[topology_logical_package_id(cpu
)] = NULL
;
453 /* After this point nothing touches the MSR anymore. */
454 wrmsr(MSR_IA32_PACKAGE_THERM_INTERRUPT
,
455 pkgdev
->msr_pkg_therm_low
, pkgdev
->msr_pkg_therm_high
);
459 * Check whether there is work scheduled and whether the work is
460 * targeted at the outgoing CPU.
462 if (pkgdev
->work_scheduled
&& was_target
) {
464 * To cancel the work we need to drop the lock, otherwise
465 * we might deadlock if the work needs to be flushed.
467 spin_unlock_irq(&pkg_temp_lock
);
468 cancel_delayed_work_sync(&pkgdev
->work
);
469 spin_lock_irq(&pkg_temp_lock
);
471 * If this is not the last cpu in the package and the work
472 * did not run after we dropped the lock above, then we
473 * need to reschedule the work, otherwise the interrupt
474 * stays disabled forever.
476 if (!lastcpu
&& pkgdev
->work_scheduled
)
477 pkg_thermal_schedule_work(target
, &pkgdev
->work
);
480 spin_unlock_irq(&pkg_temp_lock
);
482 /* Final cleanup if this is the last cpu */
488 static int pkg_thermal_cpu_online(unsigned int cpu
)
490 struct pkg_device
*pkgdev
= pkg_temp_thermal_get_dev(cpu
);
491 struct cpuinfo_x86
*c
= &cpu_data(cpu
);
494 if (!cpu_has(c
, X86_FEATURE_DTHERM
) || !cpu_has(c
, X86_FEATURE_PTS
))
497 /* If the package exists, nothing to do */
499 cpumask_set_cpu(cpu
, &pkgdev
->cpumask
);
502 return pkg_temp_thermal_device_add(cpu
);
505 static const struct x86_cpu_id __initconst pkg_temp_thermal_ids
[] = {
506 { X86_VENDOR_INTEL
, X86_FAMILY_ANY
, X86_MODEL_ANY
, X86_FEATURE_PTS
},
509 MODULE_DEVICE_TABLE(x86cpu
, pkg_temp_thermal_ids
);
511 static int __init
pkg_temp_thermal_init(void)
515 if (!x86_match_cpu(pkg_temp_thermal_ids
))
518 max_packages
= topology_max_packages();
519 packages
= kzalloc(max_packages
* sizeof(struct pkg_device
*), GFP_KERNEL
);
523 ret
= cpuhp_setup_state(CPUHP_AP_ONLINE_DYN
, "thermal/x86_pkg:online",
524 pkg_thermal_cpu_online
, pkg_thermal_cpu_offline
);
528 /* Store the state for module exit */
529 pkg_thermal_hp_state
= ret
;
531 platform_thermal_package_notify
= pkg_thermal_notify
;
532 platform_thermal_package_rate_control
= pkg_thermal_rate_control
;
534 /* Don't care if it fails */
535 pkg_temp_debugfs_init();
542 module_init(pkg_temp_thermal_init
)
544 static void __exit
pkg_temp_thermal_exit(void)
546 platform_thermal_package_notify
= NULL
;
547 platform_thermal_package_rate_control
= NULL
;
549 cpuhp_remove_state(pkg_thermal_hp_state
);
550 debugfs_remove_recursive(debugfs
);
553 module_exit(pkg_temp_thermal_exit
)
555 MODULE_DESCRIPTION("X86 PKG TEMP Thermal Driver");
556 MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");
557 MODULE_LICENSE("GPL v2");