xref: /linux/drivers/thermal/intel/therm_throt.c (revision fab183d632628381b466a41479489541ac0e29a0)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Thermal throttle event support code (such as syslog messaging and rate
4  * limiting) that was factored out from x86_64 (mce_intel.c) and i386 (p4.c).
5  *
6  * This allows consistent reporting of CPU thermal throttle events.
7  *
8  * Maintains a counter in /sys that keeps track of the number of thermal
9  * events, such that the user knows how bad the thermal problem might be
10  * (since the logging to syslog is rate limited).
11  *
12  * Author: Dmitriy Zavin (dmitriyz@google.com)
13  *
14  * Credits: Adapted from Zwane Mwaikambo's original code in mce_intel.c.
15  *          Inspired by Ross Biro's and Al Borchers' counter code.
16  */
17 #include <linux/syscore_ops.h>
18 #include <linux/interrupt.h>
19 #include <linux/notifier.h>
20 #include <linux/jiffies.h>
21 #include <linux/kernel.h>
22 #include <linux/percpu.h>
23 #include <linux/export.h>
24 #include <linux/delay.h>
25 #include <linux/types.h>
26 #include <linux/init.h>
27 #include <linux/smp.h>
28 #include <linux/sysfs.h>
29 #include <linux/cpu.h>
30 
31 #include <asm/processor.h>
32 #include <asm/thermal.h>
33 #include <asm/traps.h>
34 #include <asm/apic.h>
35 #include <asm/irq.h>
36 #include <asm/msr.h>
37 
38 #include "intel_hfi.h"
39 #include "thermal_interrupt.h"
40 
41 /* How long to wait between reporting thermal events */
42 #define CHECK_INTERVAL		(300 * HZ)
43 
44 #define THERMAL_THROTTLING_EVENT	0
45 #define POWER_LIMIT_EVENT		1
46 
47 /**
48  * struct _thermal_state - Represent the current thermal event state
49  * @next_check:			Stores the next timestamp, when it is allowed
50  *				to log the next warning message.
51  * @last_interrupt_time:	Stores the timestamp for the last threshold
52  *				high event.
53  * @therm_work:			Delayed workqueue structure
54  * @count:			Stores the current running count for thermal
55  *				or power threshold interrupts.
56  * @last_count:			Stores the previous running count for thermal
57  *				or power threshold interrupts.
58  * @max_time_ms:		This shows the maximum amount of time CPU was
59  *				in throttled state for a single thermal
60  *				threshold high to low state.
61  * @total_time_ms:		This is a cumulative time during which CPU was
62  *				in the throttled state.
63  * @rate_control_active:	Set when a throttling message is logged.
64  *				This is used for the purpose of rate-control.
65  * @new_event:			Stores the last high/low status of the
66  *				THERM_STATUS_PROCHOT or
67  *				THERM_STATUS_POWER_LIMIT.
68  * @level:			Stores whether this _thermal_state instance is
69  *				for a CORE level or for PACKAGE level.
70  * @sample_index:		Index for storing the next sample in the buffer
71  *				temp_samples[].
72  * @sample_count:		Total number of samples collected in the buffer
73  *				temp_samples[].
74  * @average:			The last moving average of temperature samples
75  * @baseline_temp:		Temperature at which thermal threshold high
76  *				interrupt was generated.
77  * @temp_samples:		Storage for temperature samples to calculate
78  *				moving average.
79  *
80  * This structure is used to represent data related to thermal state for a CPU.
81  * There is a separate storage for core and package level for each CPU.
82  */
83 struct _thermal_state {
84 	u64			next_check;
85 	u64			last_interrupt_time;
86 	struct delayed_work	therm_work;
87 	unsigned long		count;
88 	unsigned long		last_count;
89 	unsigned long		max_time_ms;
90 	unsigned long		total_time_ms;
91 	bool			rate_control_active;
92 	bool			new_event;
93 	u8			level;
94 	u8			sample_index;
95 	u8			sample_count;
96 	u8			average;
97 	u8			baseline_temp;
98 	u8			temp_samples[3];
99 };
100 
101 struct thermal_state {
102 	struct _thermal_state core_throttle;
103 	struct _thermal_state core_power_limit;
104 	struct _thermal_state package_throttle;
105 	struct _thermal_state package_power_limit;
106 	struct _thermal_state core_thresh0;
107 	struct _thermal_state core_thresh1;
108 	struct _thermal_state pkg_thresh0;
109 	struct _thermal_state pkg_thresh1;
110 };
111 
112 /* Callback to handle core threshold interrupts */
113 int (*platform_thermal_notify)(__u64 msr_val);
114 EXPORT_SYMBOL(platform_thermal_notify);
115 
116 /* Callback to handle core package threshold_interrupts */
117 int (*platform_thermal_package_notify)(__u64 msr_val);
118 EXPORT_SYMBOL_GPL(platform_thermal_package_notify);
119 
120 /* Callback support of rate control, return true, if
121  * callback has rate control */
122 bool (*platform_thermal_package_rate_control)(void);
123 EXPORT_SYMBOL_GPL(platform_thermal_package_rate_control);
124 
125 
126 static DEFINE_PER_CPU(struct thermal_state, thermal_state);
127 
128 static atomic_t therm_throt_en	= ATOMIC_INIT(0);
129 
130 static u32 lvtthmr_init __read_mostly;
131 
132 #ifdef CONFIG_SYSFS
133 #define define_therm_throt_device_one_ro(_name)				\
134 	static DEVICE_ATTR(_name, 0444,					\
135 			   therm_throt_device_show_##_name,		\
136 				   NULL)				\
137 
138 #define define_therm_throt_device_show_func(event, name)		\
139 									\
140 static ssize_t therm_throt_device_show_##event##_##name(		\
141 			struct device *dev,				\
142 			struct device_attribute *attr,			\
143 			char *buf)					\
144 {									\
145 	unsigned int cpu = dev->id;					\
146 	ssize_t ret;							\
147 									\
148 	preempt_disable();	/* CPU hotplug */			\
149 	if (cpu_online(cpu)) {						\
150 		ret = sysfs_emit(buf, "%lu\n",				\
151 			per_cpu(thermal_state, cpu).event.name);	\
152 	} else								\
153 		ret = 0;						\
154 	preempt_enable();						\
155 									\
156 	return ret;							\
157 }
158 
159 define_therm_throt_device_show_func(core_throttle, count);
160 define_therm_throt_device_one_ro(core_throttle_count);
161 
162 define_therm_throt_device_show_func(core_power_limit, count);
163 define_therm_throt_device_one_ro(core_power_limit_count);
164 
165 define_therm_throt_device_show_func(package_throttle, count);
166 define_therm_throt_device_one_ro(package_throttle_count);
167 
168 define_therm_throt_device_show_func(package_power_limit, count);
169 define_therm_throt_device_one_ro(package_power_limit_count);
170 
171 define_therm_throt_device_show_func(core_throttle, max_time_ms);
172 define_therm_throt_device_one_ro(core_throttle_max_time_ms);
173 
174 define_therm_throt_device_show_func(package_throttle, max_time_ms);
175 define_therm_throt_device_one_ro(package_throttle_max_time_ms);
176 
177 define_therm_throt_device_show_func(core_throttle, total_time_ms);
178 define_therm_throt_device_one_ro(core_throttle_total_time_ms);
179 
180 define_therm_throt_device_show_func(package_throttle, total_time_ms);
181 define_therm_throt_device_one_ro(package_throttle_total_time_ms);
182 
183 static struct attribute *thermal_throttle_attrs[] = {
184 	&dev_attr_core_throttle_count.attr,
185 	&dev_attr_core_throttle_max_time_ms.attr,
186 	&dev_attr_core_throttle_total_time_ms.attr,
187 	NULL
188 };
189 
190 static const struct attribute_group thermal_attr_group = {
191 	.attrs	= thermal_throttle_attrs,
192 	.name	= "thermal_throttle"
193 };
194 #endif /* CONFIG_SYSFS */
195 
196 #define THERM_THROT_POLL_INTERVAL	HZ
197 #define THERM_STATUS_PROCHOT_LOG	BIT(1)
198 
199 static u64 therm_intr_core_clear_mask;
200 static u64 therm_intr_pkg_clear_mask;
201 
thermal_intr_init_core_clear_mask(void)202 static void thermal_intr_init_core_clear_mask(void)
203 {
204 	if (therm_intr_core_clear_mask)
205 		return;
206 
207 	/*
208 	 * Reference: Intel SDM  Volume 4
209 	 * "Table 2-2. IA-32 Architectural MSRs", MSR 0x19C
210 	 * IA32_THERM_STATUS.
211 	 */
212 
213 	/*
214 	 * Bit 1, 3, 5: CPUID.01H:EDX[22] = 1. This driver will not
215 	 * enable interrupts, when 0 as it checks for X86_FEATURE_ACPI.
216 	 */
217 	therm_intr_core_clear_mask = (BIT(1) | BIT(3) | BIT(5));
218 
219 	/*
220 	 * Bit 7 and 9: Thermal Threshold #1 and #2 log
221 	 * If CPUID.01H:ECX[8] = 1
222 	 */
223 	if (boot_cpu_has(X86_FEATURE_TM2))
224 		therm_intr_core_clear_mask |= (BIT(7) | BIT(9));
225 
226 	/* Bit 11: Power Limitation log (R/WC0) If CPUID.06H:EAX[4] = 1 */
227 	if (boot_cpu_has(X86_FEATURE_PLN))
228 		therm_intr_core_clear_mask |= BIT(11);
229 
230 	/*
231 	 * Bit 13: Current Limit log (R/WC0) If CPUID.06H:EAX[7] = 1
232 	 * Bit 15: Cross Domain Limit log (R/WC0) If CPUID.06H:EAX[7] = 1
233 	 */
234 	if (boot_cpu_has(X86_FEATURE_HWP))
235 		therm_intr_core_clear_mask |= (BIT(13) | BIT(15));
236 }
237 
thermal_intr_init_pkg_clear_mask(void)238 static void thermal_intr_init_pkg_clear_mask(void)
239 {
240 	if (therm_intr_pkg_clear_mask)
241 		return;
242 
243 	/*
244 	 * Reference: Intel SDM  Volume 4
245 	 * "Table 2-2. IA-32 Architectural MSRs", MSR 0x1B1
246 	 * IA32_PACKAGE_THERM_STATUS.
247 	 */
248 
249 	/* All bits except BITs 25 and 26 depend on CPUID.06H: EAX[6] = 1 */
250 	if (boot_cpu_has(X86_FEATURE_PTS))
251 		therm_intr_pkg_clear_mask = (BIT(1) | BIT(3) | BIT(5) | BIT(7) | BIT(9) | BIT(11));
252 
253 	/*
254 	 * Intel SDM Volume 1: Thermal and Power Management Leaf
255 	 * Bit 26: CPUID.06H: EAX[19] = 1
256 	 */
257 	if (boot_cpu_has(X86_FEATURE_HFI))
258 		therm_intr_pkg_clear_mask |= BIT(26);
259 
260 	/*
261 	 * Intel SDM Volume 1: Thermal and Power Management Leaf
262 	 * Bit 25: CPUID.06H: EAX[24] = 1
263 	 */
264 	if (boot_cpu_has(X86_FEATURE_DPTI))
265 		therm_intr_pkg_clear_mask |= BIT(25);
266 }
267 
268 /*
269  * Clear the bits in package thermal status register for bit = 1
270  * in bitmask
271  */
thermal_clear_package_intr_status(int level,u64 bit_mask)272 void thermal_clear_package_intr_status(int level, u64 bit_mask)
273 {
274 	u64 msr_val;
275 	int msr;
276 
277 	if (level == CORE_LEVEL) {
278 		msr  = MSR_IA32_THERM_STATUS;
279 		msr_val = therm_intr_core_clear_mask;
280 	} else {
281 		msr  = MSR_IA32_PACKAGE_THERM_STATUS;
282 		msr_val = therm_intr_pkg_clear_mask;
283 	}
284 
285 	msr_val &= ~bit_mask;
286 	wrmsrq(msr, msr_val);
287 }
288 EXPORT_SYMBOL_GPL(thermal_clear_package_intr_status);
289 
get_therm_status(int level,bool * proc_hot,u8 * temp)290 static void get_therm_status(int level, bool *proc_hot, u8 *temp)
291 {
292 	int msr;
293 	u64 msr_val;
294 
295 	if (level == CORE_LEVEL)
296 		msr = MSR_IA32_THERM_STATUS;
297 	else
298 		msr = MSR_IA32_PACKAGE_THERM_STATUS;
299 
300 	rdmsrq(msr, msr_val);
301 	if (msr_val & THERM_STATUS_PROCHOT_LOG)
302 		*proc_hot = true;
303 	else
304 		*proc_hot = false;
305 
306 	*temp = (msr_val >> 16) & 0x7F;
307 }
308 
throttle_active_work(struct work_struct * work)309 static void __maybe_unused throttle_active_work(struct work_struct *work)
310 {
311 	struct _thermal_state *state = container_of(to_delayed_work(work),
312 						struct _thermal_state, therm_work);
313 	unsigned int i, avg, this_cpu = smp_processor_id();
314 	u64 now = get_jiffies_64();
315 	bool hot;
316 	u8 temp;
317 
318 	get_therm_status(state->level, &hot, &temp);
319 	/* temperature value is offset from the max so lesser means hotter */
320 	if (!hot && temp > state->baseline_temp) {
321 		if (state->rate_control_active)
322 			pr_info("CPU%d: %s temperature/speed normal (total events = %lu)\n",
323 				this_cpu,
324 				state->level == CORE_LEVEL ? "Core" : "Package",
325 				state->count);
326 
327 		state->rate_control_active = false;
328 		return;
329 	}
330 
331 	if (time_before64(now, state->next_check) &&
332 			  state->rate_control_active)
333 		goto re_arm;
334 
335 	state->next_check = now + CHECK_INTERVAL;
336 
337 	if (state->count != state->last_count) {
338 		/* There was one new thermal interrupt */
339 		state->last_count = state->count;
340 		state->average = 0;
341 		state->sample_count = 0;
342 		state->sample_index = 0;
343 	}
344 
345 	state->temp_samples[state->sample_index] = temp;
346 	state->sample_count++;
347 	state->sample_index = (state->sample_index + 1) % ARRAY_SIZE(state->temp_samples);
348 	if (state->sample_count < ARRAY_SIZE(state->temp_samples))
349 		goto re_arm;
350 
351 	avg = 0;
352 	for (i = 0; i < ARRAY_SIZE(state->temp_samples); ++i)
353 		avg += state->temp_samples[i];
354 
355 	avg /= ARRAY_SIZE(state->temp_samples);
356 
357 	if (state->average > avg) {
358 		pr_warn("CPU%d: %s temperature is above threshold, cpu clock is throttled (total events = %lu)\n",
359 			this_cpu,
360 			state->level == CORE_LEVEL ? "Core" : "Package",
361 			state->count);
362 		state->rate_control_active = true;
363 	}
364 
365 	state->average = avg;
366 
367 re_arm:
368 	thermal_clear_package_intr_status(state->level, THERM_STATUS_PROCHOT_LOG);
369 	schedule_delayed_work_on(this_cpu, &state->therm_work, THERM_THROT_POLL_INTERVAL);
370 }
371 
372 /***
373  * therm_throt_process - Process thermal throttling event from interrupt
374  * @curr: Whether the condition is current or not (boolean), since the
375  *        thermal interrupt normally gets called both when the thermal
376  *        event begins and once the event has ended.
377  *
378  * This function is called by the thermal interrupt after the
379  * IRQ has been acknowledged.
380  *
381  * It will take care of rate limiting and printing messages to the syslog.
382  */
therm_throt_process(bool new_event,int event,int level)383 static void therm_throt_process(bool new_event, int event, int level)
384 {
385 	struct _thermal_state *state;
386 	unsigned int this_cpu = smp_processor_id();
387 	bool old_event;
388 	u64 now;
389 	struct thermal_state *pstate = &per_cpu(thermal_state, this_cpu);
390 
391 	now = get_jiffies_64();
392 	if (level == CORE_LEVEL) {
393 		if (event == THERMAL_THROTTLING_EVENT)
394 			state = &pstate->core_throttle;
395 		else if (event == POWER_LIMIT_EVENT)
396 			state = &pstate->core_power_limit;
397 		else
398 			return;
399 	} else if (level == PACKAGE_LEVEL) {
400 		if (event == THERMAL_THROTTLING_EVENT)
401 			state = &pstate->package_throttle;
402 		else if (event == POWER_LIMIT_EVENT)
403 			state = &pstate->package_power_limit;
404 		else
405 			return;
406 	} else
407 		return;
408 
409 	old_event = state->new_event;
410 	state->new_event = new_event;
411 
412 	if (new_event)
413 		state->count++;
414 
415 	if (event != THERMAL_THROTTLING_EVENT)
416 		return;
417 
418 	if (new_event && !state->last_interrupt_time) {
419 		bool hot;
420 		u8 temp;
421 
422 		get_therm_status(state->level, &hot, &temp);
423 		/*
424 		 * Ignore short temperature spike as the system is not close
425 		 * to PROCHOT. 10C offset is large enough to ignore. It is
426 		 * already dropped from the high threshold temperature.
427 		 */
428 		if (temp > 10)
429 			return;
430 
431 		state->baseline_temp = temp;
432 		state->last_interrupt_time = now;
433 		schedule_delayed_work_on(this_cpu, &state->therm_work, THERM_THROT_POLL_INTERVAL);
434 	} else if (old_event && state->last_interrupt_time) {
435 		unsigned long throttle_time;
436 
437 		throttle_time = jiffies_delta_to_msecs(now - state->last_interrupt_time);
438 		if (throttle_time > state->max_time_ms)
439 			state->max_time_ms = throttle_time;
440 		state->total_time_ms += throttle_time;
441 		state->last_interrupt_time = 0;
442 	}
443 }
444 
thresh_event_valid(int level,int event)445 static int thresh_event_valid(int level, int event)
446 {
447 	struct _thermal_state *state;
448 	unsigned int this_cpu = smp_processor_id();
449 	struct thermal_state *pstate = &per_cpu(thermal_state, this_cpu);
450 	u64 now = get_jiffies_64();
451 
452 	if (level == PACKAGE_LEVEL)
453 		state = (event == 0) ? &pstate->pkg_thresh0 :
454 						&pstate->pkg_thresh1;
455 	else
456 		state = (event == 0) ? &pstate->core_thresh0 :
457 						&pstate->core_thresh1;
458 
459 	if (time_before64(now, state->next_check))
460 		return 0;
461 
462 	state->next_check = now + CHECK_INTERVAL;
463 
464 	return 1;
465 }
466 
467 static bool int_pln_enable;
int_pln_enable_setup(char * s)468 static int __init int_pln_enable_setup(char *s)
469 {
470 	int_pln_enable = true;
471 
472 	return 1;
473 }
474 __setup("int_pln_enable", int_pln_enable_setup);
475 
476 #ifdef CONFIG_SYSFS
477 /* Add/Remove thermal_throttle interface for CPU device: */
thermal_throttle_add_dev(struct device * dev,unsigned int cpu)478 static int thermal_throttle_add_dev(struct device *dev, unsigned int cpu)
479 {
480 	int err;
481 	struct cpuinfo_x86 *c = &cpu_data(cpu);
482 
483 	err = sysfs_create_group(&dev->kobj, &thermal_attr_group);
484 	if (err)
485 		return err;
486 
487 	if (cpu_has(c, X86_FEATURE_PLN) && int_pln_enable) {
488 		err = sysfs_add_file_to_group(&dev->kobj,
489 					      &dev_attr_core_power_limit_count.attr,
490 					      thermal_attr_group.name);
491 		if (err)
492 			goto del_group;
493 	}
494 
495 	if (cpu_has(c, X86_FEATURE_PTS)) {
496 		err = sysfs_add_file_to_group(&dev->kobj,
497 					      &dev_attr_package_throttle_count.attr,
498 					      thermal_attr_group.name);
499 		if (err)
500 			goto del_group;
501 
502 		err = sysfs_add_file_to_group(&dev->kobj,
503 					      &dev_attr_package_throttle_max_time_ms.attr,
504 					      thermal_attr_group.name);
505 		if (err)
506 			goto del_group;
507 
508 		err = sysfs_add_file_to_group(&dev->kobj,
509 					      &dev_attr_package_throttle_total_time_ms.attr,
510 					      thermal_attr_group.name);
511 		if (err)
512 			goto del_group;
513 
514 		if (cpu_has(c, X86_FEATURE_PLN) && int_pln_enable) {
515 			err = sysfs_add_file_to_group(&dev->kobj,
516 					&dev_attr_package_power_limit_count.attr,
517 					thermal_attr_group.name);
518 			if (err)
519 				goto del_group;
520 		}
521 	}
522 
523 	return 0;
524 
525 del_group:
526 	sysfs_remove_group(&dev->kobj, &thermal_attr_group);
527 
528 	return err;
529 }
530 
thermal_throttle_remove_dev(struct device * dev)531 static void thermal_throttle_remove_dev(struct device *dev)
532 {
533 	sysfs_remove_group(&dev->kobj, &thermal_attr_group);
534 }
535 
check_directed_thermal_pkg_intr_ack(void)536 static int check_directed_thermal_pkg_intr_ack(void)
537 {
538 	unsigned int count = 15000;
539 	u64 msr_val;
540 
541 	/*
542 	 * Hardware acknowledges the directed interrupt setup in 10ms or less.
543 	 * Wait 15ms to be safe.
544 	 */
545 	do {
546 		rdmsrq(MSR_IA32_PACKAGE_THERM_STATUS, msr_val);
547 		udelay(1);
548 	} while (!(msr_val & PACKAGE_THERM_STATUS_DPTI_ACK) && --count);
549 
550 	if (!count)
551 		return -ETIMEDOUT;
552 
553 	thermal_clear_package_intr_status(PACKAGE_LEVEL,
554 					  PACKAGE_THERM_STATUS_DPTI_ACK);
555 
556 	return 0;
557 }
558 
config_directed_thermal_pkg_intr(void * info)559 static void config_directed_thermal_pkg_intr(void *info)
560 {
561 	bool enable = *((bool *)info);
562 	u64 msr_val;
563 
564 	rdmsrq(MSR_IA32_THERM_INTERRUPT, msr_val);
565 
566 	if (enable)
567 		msr_val |= THERM_INT_DPTI_ENABLE;
568 	else
569 		msr_val &= ~THERM_INT_DPTI_ENABLE;
570 
571 	wrmsrq(MSR_IA32_THERM_INTERRUPT, msr_val);
572 }
573 
574 /*
575  * Accessed from CPU hotplug callbacks and from code that runs while CPU
576  * hotplug is inactive: the init and cleanup paths as well as syscore callbacks.
577  * No extra locking needed.
578  */
579 static unsigned int *directed_intr_handler_cpus;
580 
directed_thermal_pkg_intr_supported(void)581 static bool directed_thermal_pkg_intr_supported(void)
582 {
583 	if (!boot_cpu_has(X86_FEATURE_DPTI))
584 		return false;
585 
586 	if (!directed_intr_handler_cpus)
587 		return false;
588 
589 	return true;
590 }
591 
592 /*
593  * Must be called with cpu_hotplug_lock held to prevent CPUs from going offline
594  * while iterating through packages and interrupts must be enabled to avoid
595  * deadlocks in SMP function calls. The syscore shutdown callback also calls
596  * this function, but runs with CPU hotplug disabled (and interrupts enabled).
597  */
disable_directed_thermal_pkg_intr_all(void)598 static void disable_directed_thermal_pkg_intr_all(void)
599 {
600 	bool enable = false;
601 	int i;
602 
603 	if (!directed_thermal_pkg_intr_supported())
604 		return;
605 
606 	for (i = 0; i < topology_max_packages(); i++) {
607 		if (directed_intr_handler_cpus[i] == nr_cpu_ids)
608 			continue;
609 
610 		smp_call_function_single(directed_intr_handler_cpus[i],
611 					 config_directed_thermal_pkg_intr,
612 					 &enable, true);
613 	}
614 }
615 
enable_directed_thermal_pkg_intr(unsigned int cpu)616 static int enable_directed_thermal_pkg_intr(unsigned int cpu)
617 {
618 	bool enable = true;
619 	u16 pkg_id;
620 
621 	if (!directed_thermal_pkg_intr_supported())
622 		return 0;
623 
624 	pkg_id = topology_logical_package_id(cpu);
625 	if (pkg_id >= topology_max_packages())
626 		return -EINVAL;
627 
628 	/* Another CPU in this package already handles the directed interrupt. */
629 	if (directed_intr_handler_cpus[pkg_id] != nr_cpu_ids)
630 		return 0;
631 
632 	thermal_clear_package_intr_status(PACKAGE_LEVEL,
633 					  PACKAGE_THERM_STATUS_DPTI_ACK);
634 
635 	config_directed_thermal_pkg_intr(&enable);
636 	if (!check_directed_thermal_pkg_intr_ack()) {
637 		directed_intr_handler_cpus[pkg_id] = cpu;
638 		return 0;
639 	}
640 
641 	/*
642 	 * A failure indicates faulty hardware. Roll back completely so that
643 	 * no other CPU tries. This is especially important during boot as all
644 	 * CPUs may come online and would otherwise keep trying.
645 	 */
646 	enable = false;
647 	config_directed_thermal_pkg_intr(&enable);
648 
649 	return -ETIMEDOUT;
650 }
651 
disable_directed_thermal_pkg_intr(unsigned int cpu)652 static void disable_directed_thermal_pkg_intr(unsigned int cpu)
653 {
654 	unsigned int new_cpu;
655 	bool enable;
656 	u16 pkg_id;
657 
658 	if (!directed_thermal_pkg_intr_supported())
659 		return;
660 
661 	pkg_id = topology_logical_package_id(cpu);
662 	if (pkg_id >= topology_max_packages())
663 		return;
664 
665 	/* Not the CPU handling the directed interrupt. */
666 	if (directed_intr_handler_cpus[pkg_id] != cpu)
667 		return;
668 
669 	/*
670 	 * The package-level interrupt must remain directed after this CPU goes
671 	 * offline.
672 	 */
673 	new_cpu = cpumask_any_but(topology_core_cpumask(cpu), cpu);
674 	if (new_cpu < nr_cpu_ids) {
675 		enable = true;
676 		thermal_clear_package_intr_status(PACKAGE_LEVEL,
677 						  PACKAGE_THERM_STATUS_DPTI_ACK);
678 
679 		/*
680 		 * We are here via CPU hotplug. Since we are holding the
681 		 * cpu_hotplug_lock, @new_cpu cannot go offline and interrupts
682 		 * are enabled, so the SMP function call is safe.
683 		 *
684 		 * The syscore suspend callback runs with interrupts disabled,
685 		 * but it does not reach this path because all the secondary
686 		 * CPUs are offline.
687 		 */
688 		smp_call_function_single(new_cpu, config_directed_thermal_pkg_intr,
689 					 &enable, true);
690 	}
691 
692 	/*
693 	 * If hardware does not acknowledge the directed interrupt setup on
694 	 * @new_cpu, disable the redirection. Since no other CPU is configured
695 	 * to receive the package-level interrupt, all CPUs in the package will
696 	 * receive it.
697 	 */
698 	enable = false;
699 	if (new_cpu < nr_cpu_ids && check_directed_thermal_pkg_intr_ack()) {
700 		smp_call_function_single(new_cpu, config_directed_thermal_pkg_intr,
701 					 &enable, true);
702 
703 		pr_warn_once("Failed to redirect package thermal interrupt from CPU%u to CPU%u; reverting to broadcast.\n",
704 			     cpu, new_cpu);
705 
706 		new_cpu = nr_cpu_ids;
707 	}
708 
709 	/*
710 	 * Clear the directed interrupt on @cpu. Hardware acknowledgment can be
711 	 * ignored since @cpu is going offline.
712 	 */
713 	config_directed_thermal_pkg_intr(&enable);
714 
715 	directed_intr_handler_cpus[pkg_id] = (new_cpu < nr_cpu_ids) ? new_cpu : nr_cpu_ids;
716 }
717 
718 /*
719  * CPU0 may be handling the directed interrupt, but the CPU hotplug callbacks
720  * are not called for CPU0 during suspend and resume.
721  */
directed_pkg_intr_syscore_resume(void * data)722 static void directed_pkg_intr_syscore_resume(void *data)
723 {
724 	/*
725 	 * We can't do anything to handle errors. If direction fails for CPU0,
726 	 * another CPU will take over or disable direction entirely during CPU
727 	 * hotplug.
728 	 */
729 	enable_directed_thermal_pkg_intr(0);
730 }
731 
directed_pkg_intr_syscore_suspend(void * data)732 static int directed_pkg_intr_syscore_suspend(void *data)
733 {
734 	disable_directed_thermal_pkg_intr(0);
735 
736 	return 0;
737 }
738 
directed_pkg_intr_syscore_shutdown(void * data)739 static void directed_pkg_intr_syscore_shutdown(void *data)
740 {
741 	disable_directed_thermal_pkg_intr_all();
742 }
743 
744 static const struct syscore_ops directed_pkg_intr_pm_ops = {
745 	.resume = directed_pkg_intr_syscore_resume,
746 	.suspend = directed_pkg_intr_syscore_suspend,
747 	.shutdown = directed_pkg_intr_syscore_shutdown,
748 };
749 
750 static struct syscore directed_pkg_intr_pm = {
751 	.ops = &directed_pkg_intr_pm_ops,
752 };
753 
init_directed_pkg_intr(void)754 static __init void init_directed_pkg_intr(void)
755 {
756 	int i;
757 
758 	if (!boot_cpu_has(X86_FEATURE_DPTI))
759 		return;
760 
761 	directed_intr_handler_cpus = kmalloc_array(topology_max_packages(),
762 						   sizeof(*directed_intr_handler_cpus),
763 						   GFP_KERNEL);
764 	if (!directed_intr_handler_cpus)
765 		return;
766 
767 	for (i = 0; i < topology_max_packages(); i++)
768 		directed_intr_handler_cpus[i] = nr_cpu_ids;
769 
770 	register_syscore(&directed_pkg_intr_pm);
771 }
772 
cleanup_directed_pkg_thermal_intr(void)773 static void cleanup_directed_pkg_thermal_intr(void)
774 {
775 	if (!directed_thermal_pkg_intr_supported())
776 		return;
777 
778 	unregister_syscore(&directed_pkg_intr_pm);
779 	disable_directed_thermal_pkg_intr_all();
780 	kfree(directed_intr_handler_cpus);
781 	directed_intr_handler_cpus = NULL;
782 }
783 
784 /* Get notified when a cpu comes on/off. Be hotplug friendly. */
thermal_throttle_online(unsigned int cpu)785 static int thermal_throttle_online(unsigned int cpu)
786 {
787 	struct thermal_state *state = &per_cpu(thermal_state, cpu);
788 	struct device *dev = get_cpu_device(cpu);
789 	int err;
790 	u32 l;
791 
792 	err = thermal_throttle_add_dev(dev, cpu);
793 	if (err)
794 		return err;
795 
796 	state->package_throttle.level = PACKAGE_LEVEL;
797 	state->core_throttle.level = CORE_LEVEL;
798 
799 	INIT_DELAYED_WORK(&state->package_throttle.therm_work, throttle_active_work);
800 	INIT_DELAYED_WORK(&state->core_throttle.therm_work, throttle_active_work);
801 
802 	/*
803 	 * The first CPU coming online will enable the HFI. Usually this causes
804 	 * hardware to issue an HFI thermal interrupt. Such interrupt will reach
805 	 * the CPU once we enable the thermal vector in the local APIC.
806 	 */
807 	intel_hfi_online(cpu);
808 
809 	if (enable_directed_thermal_pkg_intr(cpu)) {
810 		pr_info_once("Failed to direct package thermal interrupts. All CPUs will receive it.\n");
811 		cleanup_directed_pkg_thermal_intr();
812 	}
813 
814 	/* Unmask the thermal vector after the above workqueues are initialized. */
815 	l = apic_read(APIC_LVTTHMR);
816 	apic_write(APIC_LVTTHMR, l & ~APIC_LVT_MASKED);
817 
818 	return err;
819 }
820 
thermal_throttle_offline(unsigned int cpu)821 static int thermal_throttle_offline(unsigned int cpu)
822 {
823 	struct thermal_state *state = &per_cpu(thermal_state, cpu);
824 	struct device *dev = get_cpu_device(cpu);
825 	u32 l;
826 
827 	/* Mask the thermal vector before draining evtl. pending work */
828 	l = apic_read(APIC_LVTTHMR);
829 	apic_write(APIC_LVTTHMR, l | APIC_LVT_MASKED);
830 
831 	disable_directed_thermal_pkg_intr(cpu);
832 
833 	intel_hfi_offline(cpu);
834 
835 	cancel_delayed_work_sync(&state->package_throttle.therm_work);
836 	cancel_delayed_work_sync(&state->core_throttle.therm_work);
837 
838 	state->package_throttle.rate_control_active = false;
839 	state->core_throttle.rate_control_active = false;
840 
841 	thermal_throttle_remove_dev(dev);
842 	return 0;
843 }
844 
thermal_throttle_init_device(void)845 static __init int thermal_throttle_init_device(void)
846 {
847 	int ret;
848 
849 	if (!atomic_read(&therm_throt_en))
850 		return 0;
851 
852 	init_directed_pkg_intr();
853 
854 	intel_hfi_init();
855 
856 	ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "x86/therm:online",
857 				thermal_throttle_online,
858 				thermal_throttle_offline);
859 	if (ret >= 0)
860 		return 0;
861 
862 	cleanup_directed_pkg_thermal_intr();
863 
864 	return ret;
865 }
866 device_initcall(thermal_throttle_init_device);
867 
868 #endif /* CONFIG_SYSFS */
869 
notify_package_thresholds(__u64 msr_val)870 static void notify_package_thresholds(__u64 msr_val)
871 {
872 	bool notify_thres_0 = false;
873 	bool notify_thres_1 = false;
874 
875 	if (!platform_thermal_package_notify)
876 		return;
877 
878 	/* lower threshold check */
879 	if (msr_val & THERM_LOG_THRESHOLD0)
880 		notify_thres_0 = true;
881 	/* higher threshold check */
882 	if (msr_val & THERM_LOG_THRESHOLD1)
883 		notify_thres_1 = true;
884 
885 	if (!notify_thres_0 && !notify_thres_1)
886 		return;
887 
888 	if (platform_thermal_package_rate_control &&
889 		platform_thermal_package_rate_control()) {
890 		/* Rate control is implemented in callback */
891 		platform_thermal_package_notify(msr_val);
892 		return;
893 	}
894 
895 	/* lower threshold reached */
896 	if (notify_thres_0 && thresh_event_valid(PACKAGE_LEVEL, 0))
897 		platform_thermal_package_notify(msr_val);
898 	/* higher threshold reached */
899 	if (notify_thres_1 && thresh_event_valid(PACKAGE_LEVEL, 1))
900 		platform_thermal_package_notify(msr_val);
901 }
902 
notify_thresholds(__u64 msr_val)903 static void notify_thresholds(__u64 msr_val)
904 {
905 	/* check whether the interrupt handler is defined;
906 	 * otherwise simply return
907 	 */
908 	if (!platform_thermal_notify)
909 		return;
910 
911 	/* lower threshold reached */
912 	if ((msr_val & THERM_LOG_THRESHOLD0) &&
913 			thresh_event_valid(CORE_LEVEL, 0))
914 		platform_thermal_notify(msr_val);
915 	/* higher threshold reached */
916 	if ((msr_val & THERM_LOG_THRESHOLD1) &&
917 			thresh_event_valid(CORE_LEVEL, 1))
918 		platform_thermal_notify(msr_val);
919 }
920 
notify_hwp_interrupt(void)921 void __weak notify_hwp_interrupt(void)
922 {
923 	wrmsrq_safe(MSR_HWP_STATUS, 0);
924 }
925 
926 /* Thermal transition interrupt handler */
intel_thermal_interrupt(void)927 void intel_thermal_interrupt(void)
928 {
929 	__u64 msr_val;
930 
931 	if (cpu_feature_enabled(X86_FEATURE_HWP))
932 		notify_hwp_interrupt();
933 
934 	rdmsrq(MSR_IA32_THERM_STATUS, msr_val);
935 
936 	/* Check for violation of core thermal thresholds*/
937 	notify_thresholds(msr_val);
938 
939 	therm_throt_process(msr_val & THERM_STATUS_PROCHOT,
940 			    THERMAL_THROTTLING_EVENT,
941 			    CORE_LEVEL);
942 
943 	if (this_cpu_has(X86_FEATURE_PLN) && int_pln_enable)
944 		therm_throt_process(msr_val & THERM_STATUS_POWER_LIMIT,
945 					POWER_LIMIT_EVENT,
946 					CORE_LEVEL);
947 
948 	if (this_cpu_has(X86_FEATURE_PTS)) {
949 		rdmsrq(MSR_IA32_PACKAGE_THERM_STATUS, msr_val);
950 		/* check violations of package thermal thresholds */
951 		notify_package_thresholds(msr_val);
952 		therm_throt_process(msr_val & PACKAGE_THERM_STATUS_PROCHOT,
953 					THERMAL_THROTTLING_EVENT,
954 					PACKAGE_LEVEL);
955 		if (this_cpu_has(X86_FEATURE_PLN) && int_pln_enable)
956 			therm_throt_process(msr_val &
957 					PACKAGE_THERM_STATUS_POWER_LIMIT,
958 					POWER_LIMIT_EVENT,
959 					PACKAGE_LEVEL);
960 
961 		if (this_cpu_has(X86_FEATURE_HFI))
962 			intel_hfi_process_event(msr_val &
963 						PACKAGE_THERM_STATUS_HFI_UPDATED);
964 	}
965 }
966 
967 /* Thermal monitoring depends on APIC, ACPI and clock modulation */
intel_thermal_supported(struct cpuinfo_x86 * c)968 static int intel_thermal_supported(struct cpuinfo_x86 *c)
969 {
970 	if (!boot_cpu_has(X86_FEATURE_APIC))
971 		return 0;
972 	if (!cpu_has(c, X86_FEATURE_ACPI) || !cpu_has(c, X86_FEATURE_ACC))
973 		return 0;
974 	return 1;
975 }
976 
x86_thermal_enabled(void)977 bool x86_thermal_enabled(void)
978 {
979 	return atomic_read(&therm_throt_en);
980 }
981 
therm_lvt_init(void)982 void __init therm_lvt_init(void)
983 {
984 	/*
985 	 * This function is only called on boot CPU. Save the init thermal
986 	 * LVT value on BSP and use that value to restore APs' thermal LVT
987 	 * entry BIOS programmed later
988 	 */
989 	if (intel_thermal_supported(&boot_cpu_data))
990 		lvtthmr_init = apic_read(APIC_LVTTHMR);
991 }
992 
intel_init_thermal(struct cpuinfo_x86 * c)993 void intel_init_thermal(struct cpuinfo_x86 *c)
994 {
995 	unsigned int cpu = smp_processor_id();
996 	struct msr val;
997 	int tm2 = 0;
998 
999 	if (!intel_thermal_supported(c))
1000 		return;
1001 
1002 	/*
1003 	 * First check if its enabled already, in which case there might
1004 	 * be some SMM goo which handles it, so we can't even put a handler
1005 	 * since it might be delivered via SMI already:
1006 	 */
1007 	rdmsrq(MSR_IA32_MISC_ENABLE, val.q);
1008 
1009 	val.h = lvtthmr_init;
1010 	/*
1011 	 * The initial value of thermal LVT entries on all APs always reads
1012 	 * 0x10000 because APs are woken up by BSP issuing INIT-SIPI-SIPI
1013 	 * sequence to them and LVT registers are reset to 0s except for
1014 	 * the mask bits which are set to 1s when APs receive INIT IPI.
1015 	 * If BIOS takes over the thermal interrupt and sets its interrupt
1016 	 * delivery mode to SMI (not fixed), it restores the value that the
1017 	 * BIOS has programmed on AP based on BSP's info we saved since BIOS
1018 	 * is always setting the same value for all threads/cores.
1019 	 */
1020 	if ((val.h & APIC_DM_FIXED_MASK) != APIC_DM_FIXED)
1021 		apic_write(APIC_LVTTHMR, lvtthmr_init);
1022 
1023 
1024 	if ((val.l & MSR_IA32_MISC_ENABLE_TM1) && (val.h & APIC_DM_SMI)) {
1025 		if (system_state == SYSTEM_BOOTING)
1026 			pr_debug("CPU%d: Thermal monitoring handled by SMI\n", cpu);
1027 		return;
1028 	}
1029 
1030 	/* early Pentium M models use different method for enabling TM2 */
1031 	if (cpu_has(c, X86_FEATURE_TM2)) {
1032 		if (c->x86 == 6 && (c->x86_model == 9 || c->x86_model == 13)) {
1033 			rdmsrq(MSR_THERM2_CTL, val.q);
1034 			if (val.l & MSR_THERM2_CTL_TM_SELECT)
1035 				tm2 = 1;
1036 		} else if (val.l & MSR_IA32_MISC_ENABLE_TM2)
1037 			tm2 = 1;
1038 	}
1039 
1040 	/* We'll mask the thermal vector in the lapic till we're ready: */
1041 	val.h = THERMAL_APIC_VECTOR | APIC_DM_FIXED | APIC_LVT_MASKED;
1042 	apic_write(APIC_LVTTHMR, val.h);
1043 
1044 	thermal_intr_init_core_clear_mask();
1045 	thermal_intr_init_pkg_clear_mask();
1046 
1047 	rdmsrq(MSR_IA32_THERM_INTERRUPT, val.q);
1048 	if (cpu_has(c, X86_FEATURE_PLN) && !int_pln_enable) {
1049 		val.l |= THERM_INT_LOW_ENABLE | THERM_INT_HIGH_ENABLE;
1050 		val.l &= ~THERM_INT_PLN_ENABLE;
1051 	} else if (cpu_has(c, X86_FEATURE_PLN) && int_pln_enable)
1052 		val.l |= THERM_INT_LOW_ENABLE | THERM_INT_HIGH_ENABLE |
1053 			 THERM_INT_PLN_ENABLE;
1054 	else
1055 		val.l |= THERM_INT_LOW_ENABLE | THERM_INT_HIGH_ENABLE;
1056 	wrmsrq(MSR_IA32_THERM_INTERRUPT, val.q);
1057 
1058 	if (cpu_has(c, X86_FEATURE_PTS)) {
1059 		rdmsrq(MSR_IA32_PACKAGE_THERM_INTERRUPT, val.q);
1060 		if (cpu_has(c, X86_FEATURE_PLN) && !int_pln_enable) {
1061 			val.l |= PACKAGE_THERM_INT_LOW_ENABLE |
1062 				 PACKAGE_THERM_INT_HIGH_ENABLE;
1063 			val.l &= ~PACKAGE_THERM_INT_PLN_ENABLE;
1064 		} else if (cpu_has(c, X86_FEATURE_PLN) && int_pln_enable)
1065 			val.l |= PACKAGE_THERM_INT_LOW_ENABLE |
1066 				 PACKAGE_THERM_INT_HIGH_ENABLE |
1067 				 PACKAGE_THERM_INT_PLN_ENABLE;
1068 		else
1069 			val.l |= PACKAGE_THERM_INT_LOW_ENABLE |
1070 				 PACKAGE_THERM_INT_HIGH_ENABLE;
1071 		wrmsrq(MSR_IA32_PACKAGE_THERM_INTERRUPT, val.q);
1072 
1073 		if (cpu_has(c, X86_FEATURE_HFI)) {
1074 			rdmsrq(MSR_IA32_PACKAGE_THERM_INTERRUPT, val.q);
1075 			wrmsrq(MSR_IA32_PACKAGE_THERM_INTERRUPT,
1076 			       val.q | PACKAGE_THERM_INT_HFI_ENABLE);
1077 		}
1078 	}
1079 
1080 	rdmsrq(MSR_IA32_MISC_ENABLE, val.q);
1081 	wrmsrq(MSR_IA32_MISC_ENABLE, val.q | MSR_IA32_MISC_ENABLE_TM1);
1082 
1083 	pr_info_once("CPU0: Thermal monitoring enabled (%s)\n",
1084 		      tm2 ? "TM2" : "TM1");
1085 
1086 	/* enable thermal throttle processing */
1087 	atomic_set(&therm_throt_en, 1);
1088 }
1089