810143a6aa33ff81941b7f9ed169931e90ec2b49
[pandora-kernel.git] / drivers / thermal / x86_pkg_temp_thermal.c
1 /*
2  * x86_pkg_temp_thermal driver
3  * Copyright (c) 2013, Intel Corporation.
4  *
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.
8  *
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
12  * more details.
13  *
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.
16  *
17  */
18 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
19
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>
29 #include <linux/pm.h>
30 #include <linux/thermal.h>
31 #include <linux/debugfs.h>
32 #include <asm/cpu_device_id.h>
33 #include <asm/mce.h>
34
35 /*
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
43 * temperature change.
44 */
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.");
50
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.
55 */
56 #define MAX_NUMBER_OF_TRIPS     2
57 /* Limit number of package temp zones */
58 #define MAX_PKG_TEMP_ZONE_IDS   256
59
60 struct phy_dev_entry {
61         struct list_head list;
62         u16 phys_proc_id;
63         u16 first_cpu;
64         u32 tj_max;
65         int ref_cnt;
66         u32 start_pkg_therm_low;
67         u32 start_pkg_therm_high;
68         struct thermal_zone_device *tzone;
69 };
70
71 /* List maintaining number of package instances */
72 static LIST_HEAD(phy_dev_list);
73 static DEFINE_MUTEX(phy_dev_list_mutex);
74
75 /* Interrupt to work function schedule queue */
76 static DEFINE_PER_CPU(struct delayed_work, pkg_temp_thermal_threshold_work);
77
78 /* To track if the work is already scheduled on a package */
79 static u8 *pkg_work_scheduled;
80
81 /* Spin lock to prevent races with pkg_work_scheduled */
82 static spinlock_t pkg_work_lock;
83 static u16 max_phy_id;
84
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;
89
90 static int pkg_temp_debugfs_init(void)
91 {
92         struct dentry *d;
93
94         debugfs = debugfs_create_dir("pkg_temp_thermal", NULL);
95         if (!debugfs)
96                 return -ENOENT;
97
98         d = debugfs_create_u32("pkg_thres_interrupt", S_IRUGO, debugfs,
99                                 (u32 *)&pkg_interrupt_cnt);
100         if (!d)
101                 goto err_out;
102
103         d = debugfs_create_u32("pkg_thres_work", S_IRUGO, debugfs,
104                                 (u32 *)&pkg_work_cnt);
105         if (!d)
106                 goto err_out;
107
108         return 0;
109
110 err_out:
111         debugfs_remove_recursive(debugfs);
112         return -ENOENT;
113 }
114
115 static struct phy_dev_entry
116                         *pkg_temp_thermal_get_phy_entry(unsigned int cpu)
117 {
118         u16 phys_proc_id = topology_physical_package_id(cpu);
119         struct phy_dev_entry *phy_ptr;
120
121         mutex_lock(&phy_dev_list_mutex);
122
123         list_for_each_entry(phy_ptr, &phy_dev_list, list)
124                 if (phy_ptr->phys_proc_id == phys_proc_id) {
125                         mutex_unlock(&phy_dev_list_mutex);
126                         return phy_ptr;
127                 }
128
129         mutex_unlock(&phy_dev_list_mutex);
130
131         return NULL;
132 }
133
134 /*
135 * tj-max is is interesting because threshold is set relative to this
136 * temperature.
137 */
138 static int get_tj_max(int cpu, u32 *tj_max)
139 {
140         u32 eax, edx;
141         u32 val;
142         int err;
143
144         err = rdmsr_safe_on_cpu(cpu, MSR_IA32_TEMPERATURE_TARGET, &eax, &edx);
145         if (err)
146                 goto err_ret;
147         else {
148                 val = (eax >> 16) & 0xff;
149                 if (val)
150                         *tj_max = val * 1000;
151                 else {
152                         err = -EINVAL;
153                         goto err_ret;
154                 }
155         }
156
157         return 0;
158 err_ret:
159         *tj_max = 0;
160         return err;
161 }
162
163 static int sys_get_curr_temp(struct thermal_zone_device *tzd, unsigned long *temp)
164 {
165         u32 eax, edx;
166         struct phy_dev_entry *phy_dev_entry;
167
168         phy_dev_entry = tzd->devdata;
169         rdmsr_on_cpu(phy_dev_entry->first_cpu, MSR_IA32_PACKAGE_THERM_STATUS,
170                         &eax, &edx);
171         if (eax & 0x80000000) {
172                 *temp = phy_dev_entry->tj_max -
173                                 ((eax >> 16) & 0x7f) * 1000;
174                 pr_debug("sys_get_curr_temp %ld\n", *temp);
175                 return 0;
176         }
177
178         return -EINVAL;
179 }
180
181 static int sys_get_trip_temp(struct thermal_zone_device *tzd,
182                 int trip, unsigned long *temp)
183 {
184         u32 eax, edx;
185         struct phy_dev_entry *phy_dev_entry;
186         u32 mask, shift;
187         unsigned long thres_reg_value;
188         int ret;
189
190         if (trip >= MAX_NUMBER_OF_TRIPS)
191                 return -EINVAL;
192
193         phy_dev_entry = tzd->devdata;
194
195         if (trip) {
196                 mask = THERM_MASK_THRESHOLD1;
197                 shift = THERM_SHIFT_THRESHOLD1;
198         } else {
199                 mask = THERM_MASK_THRESHOLD0;
200                 shift = THERM_SHIFT_THRESHOLD0;
201         }
202
203         ret = rdmsr_on_cpu(phy_dev_entry->first_cpu,
204                                 MSR_IA32_PACKAGE_THERM_INTERRUPT, &eax, &edx);
205         if (ret < 0)
206                 return -EINVAL;
207
208         thres_reg_value = (eax & mask) >> shift;
209         if (thres_reg_value)
210                 *temp = phy_dev_entry->tj_max - thres_reg_value * 1000;
211         else
212                 *temp = 0;
213         pr_debug("sys_get_trip_temp %ld\n", *temp);
214
215         return 0;
216 }
217
218 int sys_set_trip_temp(struct thermal_zone_device *tzd, int trip,
219                                                         unsigned long temp)
220 {
221         u32 l, h;
222         struct phy_dev_entry *phy_dev_entry;
223         u32 mask, shift, intr;
224         int ret;
225
226         phy_dev_entry = tzd->devdata;
227
228         if (trip >= MAX_NUMBER_OF_TRIPS || temp >= phy_dev_entry->tj_max)
229                 return -EINVAL;
230
231         ret = rdmsr_on_cpu(phy_dev_entry->first_cpu,
232                                         MSR_IA32_PACKAGE_THERM_INTERRUPT,
233                                         &l, &h);
234         if (ret < 0)
235                 return -EINVAL;
236
237         if (trip) {
238                 mask = THERM_MASK_THRESHOLD1;
239                 shift = THERM_SHIFT_THRESHOLD1;
240                 intr = THERM_INT_THRESHOLD1_ENABLE;
241         } else {
242                 mask = THERM_MASK_THRESHOLD0;
243                 shift = THERM_SHIFT_THRESHOLD0;
244                 intr = THERM_INT_THRESHOLD0_ENABLE;
245         }
246         l &= ~mask;
247         /*
248         * When users space sets a trip temperature == 0, which is indication
249         * that, it is no longer interested in receiving notifications.
250         */
251         if (!temp)
252                 l &= ~intr;
253         else {
254                 l |= (phy_dev_entry->tj_max - temp)/1000 << shift;
255                 l |= intr;
256         }
257
258         return wrmsr_on_cpu(phy_dev_entry->first_cpu,
259                                         MSR_IA32_PACKAGE_THERM_INTERRUPT,
260                                         l, h);
261 }
262
263 static int sys_get_trip_type(struct thermal_zone_device *thermal,
264                 int trip, enum thermal_trip_type *type)
265 {
266
267         *type = THERMAL_TRIP_PASSIVE;
268
269         return 0;
270 }
271
272 /* Thermal zone callback registry */
273 static struct thermal_zone_device_ops tzone_ops = {
274         .get_temp = sys_get_curr_temp,
275         .get_trip_temp = sys_get_trip_temp,
276         .get_trip_type = sys_get_trip_type,
277         .set_trip_temp = sys_set_trip_temp,
278 };
279
280 static bool pkg_temp_thermal_platform_thermal_rate_control(void)
281 {
282         return true;
283 }
284
285 /* Enable threshold interrupt on local package/cpu */
286 static inline void enable_pkg_thres_interrupt(void)
287 {
288         u32 l, h;
289         u8 thres_0, thres_1;
290
291         rdmsr(MSR_IA32_PACKAGE_THERM_INTERRUPT, l, h);
292         /* only enable/disable if it had valid threshold value */
293         thres_0 = (l & THERM_MASK_THRESHOLD0) >> THERM_SHIFT_THRESHOLD0;
294         thres_1 = (l & THERM_MASK_THRESHOLD1) >> THERM_SHIFT_THRESHOLD1;
295         if (thres_0)
296                 l |= THERM_INT_THRESHOLD0_ENABLE;
297         if (thres_1)
298                 l |= THERM_INT_THRESHOLD1_ENABLE;
299         wrmsr(MSR_IA32_PACKAGE_THERM_INTERRUPT, l, h);
300 }
301
302 /* Disable threshold interrupt on local package/cpu */
303 static inline void disable_pkg_thres_interrupt(void)
304 {
305         u32 l, h;
306         rdmsr(MSR_IA32_PACKAGE_THERM_INTERRUPT, l, h);
307         wrmsr(MSR_IA32_PACKAGE_THERM_INTERRUPT,
308                         l & (~THERM_INT_THRESHOLD0_ENABLE) &
309                                 (~THERM_INT_THRESHOLD1_ENABLE), h);
310 }
311
312 static void pkg_temp_thermal_threshold_work_fn(struct work_struct *work)
313 {
314         __u64 msr_val;
315         int cpu = smp_processor_id();
316         int phy_id = topology_physical_package_id(cpu);
317         struct phy_dev_entry *phdev = pkg_temp_thermal_get_phy_entry(cpu);
318         bool notify = false;
319
320         if (!phdev)
321                 return;
322
323         spin_lock(&pkg_work_lock);
324         ++pkg_work_cnt;
325         if (unlikely(phy_id > max_phy_id)) {
326                 spin_unlock(&pkg_work_lock);
327                 return;
328         }
329         pkg_work_scheduled[phy_id] = 0;
330         spin_unlock(&pkg_work_lock);
331
332         enable_pkg_thres_interrupt();
333         rdmsrl(MSR_IA32_PACKAGE_THERM_STATUS, msr_val);
334         if (msr_val & THERM_LOG_THRESHOLD0) {
335                 wrmsrl(MSR_IA32_PACKAGE_THERM_STATUS,
336                                 msr_val & ~THERM_LOG_THRESHOLD0);
337                 notify = true;
338         }
339         if (msr_val & THERM_LOG_THRESHOLD1) {
340                 wrmsrl(MSR_IA32_PACKAGE_THERM_STATUS,
341                                 msr_val & ~THERM_LOG_THRESHOLD1);
342                 notify = true;
343         }
344         if (notify) {
345                 pr_debug("thermal_zone_device_update\n");
346                 thermal_zone_device_update(phdev->tzone);
347         }
348 }
349
350 static int pkg_temp_thermal_platform_thermal_notify(__u64 msr_val)
351 {
352         unsigned long flags;
353         int cpu = smp_processor_id();
354         int phy_id = topology_physical_package_id(cpu);
355
356         /*
357         * When a package is in interrupted state, all CPU's in that package
358         * are in the same interrupt state. So scheduling on any one CPU in
359         * the package is enough and simply return for others.
360         */
361         spin_lock_irqsave(&pkg_work_lock, flags);
362         ++pkg_interrupt_cnt;
363         if (unlikely(phy_id > max_phy_id) || unlikely(!pkg_work_scheduled) ||
364                         pkg_work_scheduled[phy_id]) {
365                 disable_pkg_thres_interrupt();
366                 spin_unlock_irqrestore(&pkg_work_lock, flags);
367                 return -EINVAL;
368         }
369         pkg_work_scheduled[phy_id] = 1;
370         spin_unlock_irqrestore(&pkg_work_lock, flags);
371
372         disable_pkg_thres_interrupt();
373         schedule_delayed_work_on(cpu,
374                                 &per_cpu(pkg_temp_thermal_threshold_work, cpu),
375                                 msecs_to_jiffies(notify_delay_ms));
376         return 0;
377 }
378
379 static int find_siblings_cpu(int cpu)
380 {
381         int i;
382         int id = topology_physical_package_id(cpu);
383
384         for_each_online_cpu(i)
385                 if (i != cpu && topology_physical_package_id(i) == id)
386                         return i;
387
388         return 0;
389 }
390
391 static int pkg_temp_thermal_device_add(unsigned int cpu)
392 {
393         int err;
394         u32 tj_max;
395         struct phy_dev_entry *phy_dev_entry;
396         char buffer[30];
397         int thres_count;
398         u32 eax, ebx, ecx, edx;
399         u8 *temp;
400
401         cpuid(6, &eax, &ebx, &ecx, &edx);
402         thres_count = ebx & 0x07;
403         if (!thres_count)
404                 return -ENODEV;
405
406         if (topology_physical_package_id(cpu) > MAX_PKG_TEMP_ZONE_IDS)
407                 return -ENODEV;
408
409         thres_count = clamp_val(thres_count, 0, MAX_NUMBER_OF_TRIPS);
410
411         err = get_tj_max(cpu, &tj_max);
412         if (err)
413                 goto err_ret;
414
415         mutex_lock(&phy_dev_list_mutex);
416
417         phy_dev_entry = kzalloc(sizeof(*phy_dev_entry), GFP_KERNEL);
418         if (!phy_dev_entry) {
419                 err = -ENOMEM;
420                 goto err_ret_unlock;
421         }
422
423         spin_lock(&pkg_work_lock);
424         if (topology_physical_package_id(cpu) > max_phy_id)
425                 max_phy_id = topology_physical_package_id(cpu);
426         temp = krealloc(pkg_work_scheduled,
427                         (max_phy_id+1) * sizeof(u8), GFP_ATOMIC);
428         if (!temp) {
429                 spin_unlock(&pkg_work_lock);
430                 err = -ENOMEM;
431                 goto err_ret_free;
432         }
433         pkg_work_scheduled = temp;
434         pkg_work_scheduled[topology_physical_package_id(cpu)] = 0;
435         spin_unlock(&pkg_work_lock);
436
437         phy_dev_entry->phys_proc_id = topology_physical_package_id(cpu);
438         phy_dev_entry->first_cpu = cpu;
439         phy_dev_entry->tj_max = tj_max;
440         phy_dev_entry->ref_cnt = 1;
441         snprintf(buffer, sizeof(buffer), "pkg-temp-%d\n",
442                                         phy_dev_entry->phys_proc_id);
443         phy_dev_entry->tzone = thermal_zone_device_register(buffer,
444                         thres_count,
445                         (thres_count == MAX_NUMBER_OF_TRIPS) ?
446                                 0x03 : 0x01,
447                         phy_dev_entry, &tzone_ops, NULL, 0, 0);
448         if (IS_ERR(phy_dev_entry->tzone)) {
449                 err = PTR_ERR(phy_dev_entry->tzone);
450                 goto err_ret_free;
451         }
452         /* Store MSR value for package thermal interrupt, to restore at exit */
453         rdmsr_on_cpu(cpu, MSR_IA32_PACKAGE_THERM_INTERRUPT,
454                                 &phy_dev_entry->start_pkg_therm_low,
455                                 &phy_dev_entry->start_pkg_therm_high);
456
457         list_add_tail(&phy_dev_entry->list, &phy_dev_list);
458         pr_debug("pkg_temp_thermal_device_add :phy_id %d cpu %d\n",
459                         phy_dev_entry->phys_proc_id, cpu);
460
461         mutex_unlock(&phy_dev_list_mutex);
462
463         return 0;
464
465 err_ret_free:
466         kfree(phy_dev_entry);
467 err_ret_unlock:
468         mutex_unlock(&phy_dev_list_mutex);
469
470 err_ret:
471         return err;
472 }
473
474 static int pkg_temp_thermal_device_remove(unsigned int cpu)
475 {
476         struct phy_dev_entry *n;
477         u16 phys_proc_id = topology_physical_package_id(cpu);
478         struct phy_dev_entry *phdev =
479                         pkg_temp_thermal_get_phy_entry(cpu);
480
481         if (!phdev)
482                 return -ENODEV;
483
484         mutex_lock(&phy_dev_list_mutex);
485         /* If we are loosing the first cpu for this package, we need change */
486         if (phdev->first_cpu == cpu) {
487                 phdev->first_cpu = find_siblings_cpu(cpu);
488                 pr_debug("thermal_device_remove: first cpu switched %d\n",
489                                         phdev->first_cpu);
490         }
491         /*
492         * It is possible that no siblings left as this was the last cpu
493         * going offline. We don't need to worry about this assignment
494         * as the phydev entry will be removed in this case and
495         * thermal zone is removed.
496         */
497         --phdev->ref_cnt;
498         pr_debug("thermal_device_remove: pkg: %d cpu %d ref_cnt %d\n",
499                                         phys_proc_id, cpu, phdev->ref_cnt);
500         if (!phdev->ref_cnt)
501                 list_for_each_entry_safe(phdev, n, &phy_dev_list, list) {
502                         if (phdev->phys_proc_id == phys_proc_id) {
503                                 thermal_zone_device_unregister(phdev->tzone);
504                                 list_del(&phdev->list);
505                                 kfree(phdev);
506                                 break;
507                         }
508                 }
509         mutex_unlock(&phy_dev_list_mutex);
510
511         return 0;
512 }
513
514 static int get_core_online(unsigned int cpu)
515 {
516         struct cpuinfo_x86 *c = &cpu_data(cpu);
517         struct phy_dev_entry *phdev = pkg_temp_thermal_get_phy_entry(cpu);
518
519         /* Check if there is already an instance for this package */
520         if (!phdev) {
521                 if (!cpu_has(c, X86_FEATURE_DTHERM) ||
522                                         !cpu_has(c, X86_FEATURE_PTS))
523                         return -ENODEV;
524                 if (pkg_temp_thermal_device_add(cpu))
525                         return -ENODEV;
526         } else {
527                 mutex_lock(&phy_dev_list_mutex);
528                 ++phdev->ref_cnt;
529                 pr_debug("get_core_online: cpu %d ref_cnt %d\n",
530                                                 cpu, phdev->ref_cnt);
531                 mutex_unlock(&phy_dev_list_mutex);
532         }
533         INIT_DELAYED_WORK(&per_cpu(pkg_temp_thermal_threshold_work, cpu),
534                         pkg_temp_thermal_threshold_work_fn);
535
536         pr_debug("get_core_online: cpu %d successful\n", cpu);
537
538         return 0;
539 }
540
541 static void put_core_offline(unsigned int cpu)
542 {
543         if (!pkg_temp_thermal_device_remove(cpu))
544                 cancel_delayed_work_sync(
545                         &per_cpu(pkg_temp_thermal_threshold_work, cpu));
546
547         pr_debug("put_core_offline: cpu %d\n", cpu);
548 }
549
550 static int pkg_temp_thermal_cpu_callback(struct notifier_block *nfb,
551                                  unsigned long action, void *hcpu)
552 {
553         unsigned int cpu = (unsigned long) hcpu;
554
555         switch (action) {
556         case CPU_ONLINE:
557         case CPU_DOWN_FAILED:
558                 get_core_online(cpu);
559                 break;
560         case CPU_DOWN_PREPARE:
561                 put_core_offline(cpu);
562                 break;
563         }
564         return NOTIFY_OK;
565 }
566
567 static struct notifier_block pkg_temp_thermal_notifier __refdata = {
568         .notifier_call = pkg_temp_thermal_cpu_callback,
569 };
570
571 static const struct x86_cpu_id __initconst pkg_temp_thermal_ids[] = {
572         { X86_VENDOR_INTEL, X86_FAMILY_ANY, X86_MODEL_ANY, X86_FEATURE_PTS },
573         {}
574 };
575 MODULE_DEVICE_TABLE(x86cpu, pkg_temp_thermal_ids);
576
577 static int __init pkg_temp_thermal_init(void)
578 {
579         int i;
580
581         if (!x86_match_cpu(pkg_temp_thermal_ids))
582                 return -ENODEV;
583
584         spin_lock_init(&pkg_work_lock);
585         platform_thermal_package_notify =
586                         pkg_temp_thermal_platform_thermal_notify;
587         platform_thermal_package_rate_control =
588                         pkg_temp_thermal_platform_thermal_rate_control;
589
590         get_online_cpus();
591         for_each_online_cpu(i)
592                 if (get_core_online(i))
593                         goto err_ret;
594         register_hotcpu_notifier(&pkg_temp_thermal_notifier);
595         put_online_cpus();
596
597         pkg_temp_debugfs_init(); /* Don't care if fails */
598
599         return 0;
600
601 err_ret:
602         get_online_cpus();
603         for_each_online_cpu(i)
604                 put_core_offline(i);
605         put_online_cpus();
606         kfree(pkg_work_scheduled);
607         platform_thermal_package_notify = NULL;
608         platform_thermal_package_rate_control = NULL;
609
610         return -ENODEV;
611 }
612
613 static void __exit pkg_temp_thermal_exit(void)
614 {
615         struct phy_dev_entry *phdev, *n;
616         int i;
617
618         get_online_cpus();
619         unregister_hotcpu_notifier(&pkg_temp_thermal_notifier);
620         mutex_lock(&phy_dev_list_mutex);
621         list_for_each_entry_safe(phdev, n, &phy_dev_list, list) {
622                 /* Retore old MSR value for package thermal interrupt */
623                 wrmsr_on_cpu(phdev->first_cpu,
624                         MSR_IA32_PACKAGE_THERM_INTERRUPT,
625                         phdev->start_pkg_therm_low,
626                         phdev->start_pkg_therm_high);
627                 thermal_zone_device_unregister(phdev->tzone);
628                 list_del(&phdev->list);
629                 kfree(phdev);
630         }
631         mutex_unlock(&phy_dev_list_mutex);
632         platform_thermal_package_notify = NULL;
633         platform_thermal_package_rate_control = NULL;
634         for_each_online_cpu(i)
635                 cancel_delayed_work_sync(
636                         &per_cpu(pkg_temp_thermal_threshold_work, i));
637         put_online_cpus();
638
639         kfree(pkg_work_scheduled);
640
641         debugfs_remove_recursive(debugfs);
642 }
643
644 module_init(pkg_temp_thermal_init)
645 module_exit(pkg_temp_thermal_exit)
646
647 MODULE_DESCRIPTION("X86 PKG TEMP Thermal Driver");
648 MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");
649 MODULE_LICENSE("GPL v2");