xref: /linux/drivers/cpufreq/acpi-cpufreq.c (revision 10d15322ed26652263a579bcb59dfd49ab8a30de)
1 /*
2  * acpi-cpufreq.c - ACPI Processor P-States Driver
3  *
4  *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
5  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
6  *  Copyright (C) 2002 - 2004 Dominik Brodowski <linux@brodo.de>
7  *  Copyright (C) 2006       Denis Sadykov <denis.m.sadykov@intel.com>
8  *
9  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
10  *
11  *  This program is free software; you can redistribute it and/or modify
12  *  it under the terms of the GNU General Public License as published by
13  *  the Free Software Foundation; either version 2 of the License, or (at
14  *  your option) any later version.
15  *
16  *  This program is distributed in the hope that it will be useful, but
17  *  WITHOUT ANY WARRANTY; without even the implied warranty of
18  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
19  *  General Public License for more details.
20  *
21  *  You should have received a copy of the GNU General Public License along
22  *  with this program; if not, write to the Free Software Foundation, Inc.,
23  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
24  *
25  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
26  */
27 
28 #include <linux/kernel.h>
29 #include <linux/module.h>
30 #include <linux/init.h>
31 #include <linux/smp.h>
32 #include <linux/sched.h>
33 #include <linux/cpufreq.h>
34 #include <linux/compiler.h>
35 #include <linux/dmi.h>
36 #include <linux/slab.h>
37 
38 #include <linux/acpi.h>
39 #include <linux/io.h>
40 #include <linux/delay.h>
41 #include <linux/uaccess.h>
42 
43 #include <acpi/processor.h>
44 
45 #include <asm/msr.h>
46 #include <asm/processor.h>
47 #include <asm/cpufeature.h>
48 
49 MODULE_AUTHOR("Paul Diefenbaugh, Dominik Brodowski");
50 MODULE_DESCRIPTION("ACPI Processor P-States Driver");
51 MODULE_LICENSE("GPL");
52 
53 #define PFX "acpi-cpufreq: "
54 
55 enum {
56 	UNDEFINED_CAPABLE = 0,
57 	SYSTEM_INTEL_MSR_CAPABLE,
58 	SYSTEM_AMD_MSR_CAPABLE,
59 	SYSTEM_IO_CAPABLE,
60 };
61 
62 #define INTEL_MSR_RANGE		(0xffff)
63 #define AMD_MSR_RANGE		(0x7)
64 
65 #define MSR_K7_HWCR_CPB_DIS	(1ULL << 25)
66 
67 struct acpi_cpufreq_data {
68 	struct cpufreq_frequency_table *freq_table;
69 	unsigned int resume;
70 	unsigned int cpu_feature;
71 	unsigned int acpi_perf_cpu;
72 	cpumask_var_t freqdomain_cpus;
73 };
74 
75 /* acpi_perf_data is a pointer to percpu data. */
76 static struct acpi_processor_performance __percpu *acpi_perf_data;
77 
78 static inline struct acpi_processor_performance *to_perf_data(struct acpi_cpufreq_data *data)
79 {
80 	return per_cpu_ptr(acpi_perf_data, data->acpi_perf_cpu);
81 }
82 
83 static struct cpufreq_driver acpi_cpufreq_driver;
84 
85 static unsigned int acpi_pstate_strict;
86 static struct msr __percpu *msrs;
87 
88 static bool boost_state(unsigned int cpu)
89 {
90 	u32 lo, hi;
91 	u64 msr;
92 
93 	switch (boot_cpu_data.x86_vendor) {
94 	case X86_VENDOR_INTEL:
95 		rdmsr_on_cpu(cpu, MSR_IA32_MISC_ENABLE, &lo, &hi);
96 		msr = lo | ((u64)hi << 32);
97 		return !(msr & MSR_IA32_MISC_ENABLE_TURBO_DISABLE);
98 	case X86_VENDOR_AMD:
99 		rdmsr_on_cpu(cpu, MSR_K7_HWCR, &lo, &hi);
100 		msr = lo | ((u64)hi << 32);
101 		return !(msr & MSR_K7_HWCR_CPB_DIS);
102 	}
103 	return false;
104 }
105 
106 static void boost_set_msrs(bool enable, const struct cpumask *cpumask)
107 {
108 	u32 cpu;
109 	u32 msr_addr;
110 	u64 msr_mask;
111 
112 	switch (boot_cpu_data.x86_vendor) {
113 	case X86_VENDOR_INTEL:
114 		msr_addr = MSR_IA32_MISC_ENABLE;
115 		msr_mask = MSR_IA32_MISC_ENABLE_TURBO_DISABLE;
116 		break;
117 	case X86_VENDOR_AMD:
118 		msr_addr = MSR_K7_HWCR;
119 		msr_mask = MSR_K7_HWCR_CPB_DIS;
120 		break;
121 	default:
122 		return;
123 	}
124 
125 	rdmsr_on_cpus(cpumask, msr_addr, msrs);
126 
127 	for_each_cpu(cpu, cpumask) {
128 		struct msr *reg = per_cpu_ptr(msrs, cpu);
129 		if (enable)
130 			reg->q &= ~msr_mask;
131 		else
132 			reg->q |= msr_mask;
133 	}
134 
135 	wrmsr_on_cpus(cpumask, msr_addr, msrs);
136 }
137 
138 static int _store_boost(int val)
139 {
140 	get_online_cpus();
141 	boost_set_msrs(val, cpu_online_mask);
142 	put_online_cpus();
143 	pr_debug("Core Boosting %sabled.\n", val ? "en" : "dis");
144 
145 	return 0;
146 }
147 
148 static ssize_t show_freqdomain_cpus(struct cpufreq_policy *policy, char *buf)
149 {
150 	struct acpi_cpufreq_data *data = policy->driver_data;
151 
152 	return cpufreq_show_cpus(data->freqdomain_cpus, buf);
153 }
154 
155 cpufreq_freq_attr_ro(freqdomain_cpus);
156 
157 #ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
158 static ssize_t store_boost(const char *buf, size_t count)
159 {
160 	int ret;
161 	unsigned long val = 0;
162 
163 	if (!acpi_cpufreq_driver.boost_supported)
164 		return -EINVAL;
165 
166 	ret = kstrtoul(buf, 10, &val);
167 	if (ret || (val > 1))
168 		return -EINVAL;
169 
170 	_store_boost((int) val);
171 
172 	return count;
173 }
174 
175 static ssize_t store_cpb(struct cpufreq_policy *policy, const char *buf,
176 			 size_t count)
177 {
178 	return store_boost(buf, count);
179 }
180 
181 static ssize_t show_cpb(struct cpufreq_policy *policy, char *buf)
182 {
183 	return sprintf(buf, "%u\n", acpi_cpufreq_driver.boost_enabled);
184 }
185 
186 cpufreq_freq_attr_rw(cpb);
187 #endif
188 
189 static int check_est_cpu(unsigned int cpuid)
190 {
191 	struct cpuinfo_x86 *cpu = &cpu_data(cpuid);
192 
193 	return cpu_has(cpu, X86_FEATURE_EST);
194 }
195 
196 static int check_amd_hwpstate_cpu(unsigned int cpuid)
197 {
198 	struct cpuinfo_x86 *cpu = &cpu_data(cpuid);
199 
200 	return cpu_has(cpu, X86_FEATURE_HW_PSTATE);
201 }
202 
203 static unsigned extract_io(u32 value, struct acpi_cpufreq_data *data)
204 {
205 	struct acpi_processor_performance *perf;
206 	int i;
207 
208 	perf = to_perf_data(data);
209 
210 	for (i = 0; i < perf->state_count; i++) {
211 		if (value == perf->states[i].status)
212 			return data->freq_table[i].frequency;
213 	}
214 	return 0;
215 }
216 
217 static unsigned extract_msr(u32 msr, struct acpi_cpufreq_data *data)
218 {
219 	struct cpufreq_frequency_table *pos;
220 	struct acpi_processor_performance *perf;
221 
222 	if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
223 		msr &= AMD_MSR_RANGE;
224 	else
225 		msr &= INTEL_MSR_RANGE;
226 
227 	perf = to_perf_data(data);
228 
229 	cpufreq_for_each_entry(pos, data->freq_table)
230 		if (msr == perf->states[pos->driver_data].status)
231 			return pos->frequency;
232 	return data->freq_table[0].frequency;
233 }
234 
235 static unsigned extract_freq(u32 val, struct acpi_cpufreq_data *data)
236 {
237 	switch (data->cpu_feature) {
238 	case SYSTEM_INTEL_MSR_CAPABLE:
239 	case SYSTEM_AMD_MSR_CAPABLE:
240 		return extract_msr(val, data);
241 	case SYSTEM_IO_CAPABLE:
242 		return extract_io(val, data);
243 	default:
244 		return 0;
245 	}
246 }
247 
248 struct msr_addr {
249 	u32 reg;
250 };
251 
252 struct io_addr {
253 	u16 port;
254 	u8 bit_width;
255 };
256 
257 struct drv_cmd {
258 	unsigned int type;
259 	const struct cpumask *mask;
260 	union {
261 		struct msr_addr msr;
262 		struct io_addr io;
263 	} addr;
264 	u32 val;
265 };
266 
267 /* Called via smp_call_function_single(), on the target CPU */
268 static void do_drv_read(void *_cmd)
269 {
270 	struct drv_cmd *cmd = _cmd;
271 	u32 h;
272 
273 	switch (cmd->type) {
274 	case SYSTEM_INTEL_MSR_CAPABLE:
275 	case SYSTEM_AMD_MSR_CAPABLE:
276 		rdmsr(cmd->addr.msr.reg, cmd->val, h);
277 		break;
278 	case SYSTEM_IO_CAPABLE:
279 		acpi_os_read_port((acpi_io_address)cmd->addr.io.port,
280 				&cmd->val,
281 				(u32)cmd->addr.io.bit_width);
282 		break;
283 	default:
284 		break;
285 	}
286 }
287 
288 /* Called via smp_call_function_many(), on the target CPUs */
289 static void do_drv_write(void *_cmd)
290 {
291 	struct drv_cmd *cmd = _cmd;
292 	u32 lo, hi;
293 
294 	switch (cmd->type) {
295 	case SYSTEM_INTEL_MSR_CAPABLE:
296 		rdmsr(cmd->addr.msr.reg, lo, hi);
297 		lo = (lo & ~INTEL_MSR_RANGE) | (cmd->val & INTEL_MSR_RANGE);
298 		wrmsr(cmd->addr.msr.reg, lo, hi);
299 		break;
300 	case SYSTEM_AMD_MSR_CAPABLE:
301 		wrmsr(cmd->addr.msr.reg, cmd->val, 0);
302 		break;
303 	case SYSTEM_IO_CAPABLE:
304 		acpi_os_write_port((acpi_io_address)cmd->addr.io.port,
305 				cmd->val,
306 				(u32)cmd->addr.io.bit_width);
307 		break;
308 	default:
309 		break;
310 	}
311 }
312 
313 static void drv_read(struct drv_cmd *cmd)
314 {
315 	int err;
316 	cmd->val = 0;
317 
318 	err = smp_call_function_any(cmd->mask, do_drv_read, cmd, 1);
319 	WARN_ON_ONCE(err);	/* smp_call_function_any() was buggy? */
320 }
321 
322 static void drv_write(struct drv_cmd *cmd)
323 {
324 	int this_cpu;
325 
326 	this_cpu = get_cpu();
327 	if (cpumask_test_cpu(this_cpu, cmd->mask))
328 		do_drv_write(cmd);
329 	smp_call_function_many(cmd->mask, do_drv_write, cmd, 1);
330 	put_cpu();
331 }
332 
333 static u32
334 get_cur_val(const struct cpumask *mask, struct acpi_cpufreq_data *data)
335 {
336 	struct acpi_processor_performance *perf;
337 	struct drv_cmd cmd;
338 
339 	if (unlikely(cpumask_empty(mask)))
340 		return 0;
341 
342 	switch (data->cpu_feature) {
343 	case SYSTEM_INTEL_MSR_CAPABLE:
344 		cmd.type = SYSTEM_INTEL_MSR_CAPABLE;
345 		cmd.addr.msr.reg = MSR_IA32_PERF_CTL;
346 		break;
347 	case SYSTEM_AMD_MSR_CAPABLE:
348 		cmd.type = SYSTEM_AMD_MSR_CAPABLE;
349 		cmd.addr.msr.reg = MSR_AMD_PERF_CTL;
350 		break;
351 	case SYSTEM_IO_CAPABLE:
352 		cmd.type = SYSTEM_IO_CAPABLE;
353 		perf = to_perf_data(data);
354 		cmd.addr.io.port = perf->control_register.address;
355 		cmd.addr.io.bit_width = perf->control_register.bit_width;
356 		break;
357 	default:
358 		return 0;
359 	}
360 
361 	cmd.mask = mask;
362 	drv_read(&cmd);
363 
364 	pr_debug("get_cur_val = %u\n", cmd.val);
365 
366 	return cmd.val;
367 }
368 
369 static unsigned int get_cur_freq_on_cpu(unsigned int cpu)
370 {
371 	struct acpi_cpufreq_data *data;
372 	struct cpufreq_policy *policy;
373 	unsigned int freq;
374 	unsigned int cached_freq;
375 
376 	pr_debug("get_cur_freq_on_cpu (%d)\n", cpu);
377 
378 	policy = cpufreq_cpu_get_raw(cpu);
379 	if (unlikely(!policy))
380 		return 0;
381 
382 	data = policy->driver_data;
383 	if (unlikely(!data || !data->freq_table))
384 		return 0;
385 
386 	cached_freq = data->freq_table[to_perf_data(data)->state].frequency;
387 	freq = extract_freq(get_cur_val(cpumask_of(cpu), data), data);
388 	if (freq != cached_freq) {
389 		/*
390 		 * The dreaded BIOS frequency change behind our back.
391 		 * Force set the frequency on next target call.
392 		 */
393 		data->resume = 1;
394 	}
395 
396 	pr_debug("cur freq = %u\n", freq);
397 
398 	return freq;
399 }
400 
401 static unsigned int check_freqs(const struct cpumask *mask, unsigned int freq,
402 				struct acpi_cpufreq_data *data)
403 {
404 	unsigned int cur_freq;
405 	unsigned int i;
406 
407 	for (i = 0; i < 100; i++) {
408 		cur_freq = extract_freq(get_cur_val(mask, data), data);
409 		if (cur_freq == freq)
410 			return 1;
411 		udelay(10);
412 	}
413 	return 0;
414 }
415 
416 static int acpi_cpufreq_target(struct cpufreq_policy *policy,
417 			       unsigned int index)
418 {
419 	struct acpi_cpufreq_data *data = policy->driver_data;
420 	struct acpi_processor_performance *perf;
421 	struct drv_cmd cmd;
422 	unsigned int next_perf_state = 0; /* Index into perf table */
423 	int result = 0;
424 
425 	if (unlikely(data == NULL || data->freq_table == NULL)) {
426 		return -ENODEV;
427 	}
428 
429 	perf = to_perf_data(data);
430 	next_perf_state = data->freq_table[index].driver_data;
431 	if (perf->state == next_perf_state) {
432 		if (unlikely(data->resume)) {
433 			pr_debug("Called after resume, resetting to P%d\n",
434 				next_perf_state);
435 			data->resume = 0;
436 		} else {
437 			pr_debug("Already at target state (P%d)\n",
438 				next_perf_state);
439 			goto out;
440 		}
441 	}
442 
443 	switch (data->cpu_feature) {
444 	case SYSTEM_INTEL_MSR_CAPABLE:
445 		cmd.type = SYSTEM_INTEL_MSR_CAPABLE;
446 		cmd.addr.msr.reg = MSR_IA32_PERF_CTL;
447 		cmd.val = (u32) perf->states[next_perf_state].control;
448 		break;
449 	case SYSTEM_AMD_MSR_CAPABLE:
450 		cmd.type = SYSTEM_AMD_MSR_CAPABLE;
451 		cmd.addr.msr.reg = MSR_AMD_PERF_CTL;
452 		cmd.val = (u32) perf->states[next_perf_state].control;
453 		break;
454 	case SYSTEM_IO_CAPABLE:
455 		cmd.type = SYSTEM_IO_CAPABLE;
456 		cmd.addr.io.port = perf->control_register.address;
457 		cmd.addr.io.bit_width = perf->control_register.bit_width;
458 		cmd.val = (u32) perf->states[next_perf_state].control;
459 		break;
460 	default:
461 		result = -ENODEV;
462 		goto out;
463 	}
464 
465 	/* cpufreq holds the hotplug lock, so we are safe from here on */
466 	if (policy->shared_type != CPUFREQ_SHARED_TYPE_ANY)
467 		cmd.mask = policy->cpus;
468 	else
469 		cmd.mask = cpumask_of(policy->cpu);
470 
471 	drv_write(&cmd);
472 
473 	if (acpi_pstate_strict) {
474 		if (!check_freqs(cmd.mask, data->freq_table[index].frequency,
475 					data)) {
476 			pr_debug("acpi_cpufreq_target failed (%d)\n",
477 				policy->cpu);
478 			result = -EAGAIN;
479 		}
480 	}
481 
482 	if (!result)
483 		perf->state = next_perf_state;
484 
485 out:
486 	return result;
487 }
488 
489 static unsigned long
490 acpi_cpufreq_guess_freq(struct acpi_cpufreq_data *data, unsigned int cpu)
491 {
492 	struct acpi_processor_performance *perf;
493 
494 	perf = to_perf_data(data);
495 	if (cpu_khz) {
496 		/* search the closest match to cpu_khz */
497 		unsigned int i;
498 		unsigned long freq;
499 		unsigned long freqn = perf->states[0].core_frequency * 1000;
500 
501 		for (i = 0; i < (perf->state_count-1); i++) {
502 			freq = freqn;
503 			freqn = perf->states[i+1].core_frequency * 1000;
504 			if ((2 * cpu_khz) > (freqn + freq)) {
505 				perf->state = i;
506 				return freq;
507 			}
508 		}
509 		perf->state = perf->state_count-1;
510 		return freqn;
511 	} else {
512 		/* assume CPU is at P0... */
513 		perf->state = 0;
514 		return perf->states[0].core_frequency * 1000;
515 	}
516 }
517 
518 static void free_acpi_perf_data(void)
519 {
520 	unsigned int i;
521 
522 	/* Freeing a NULL pointer is OK, and alloc_percpu zeroes. */
523 	for_each_possible_cpu(i)
524 		free_cpumask_var(per_cpu_ptr(acpi_perf_data, i)
525 				 ->shared_cpu_map);
526 	free_percpu(acpi_perf_data);
527 }
528 
529 static int boost_notify(struct notifier_block *nb, unsigned long action,
530 		      void *hcpu)
531 {
532 	unsigned cpu = (long)hcpu;
533 	const struct cpumask *cpumask;
534 
535 	cpumask = get_cpu_mask(cpu);
536 
537 	/*
538 	 * Clear the boost-disable bit on the CPU_DOWN path so that
539 	 * this cpu cannot block the remaining ones from boosting. On
540 	 * the CPU_UP path we simply keep the boost-disable flag in
541 	 * sync with the current global state.
542 	 */
543 
544 	switch (action) {
545 	case CPU_UP_PREPARE:
546 	case CPU_UP_PREPARE_FROZEN:
547 		boost_set_msrs(acpi_cpufreq_driver.boost_enabled, cpumask);
548 		break;
549 
550 	case CPU_DOWN_PREPARE:
551 	case CPU_DOWN_PREPARE_FROZEN:
552 		boost_set_msrs(1, cpumask);
553 		break;
554 
555 	default:
556 		break;
557 	}
558 
559 	return NOTIFY_OK;
560 }
561 
562 
563 static struct notifier_block boost_nb = {
564 	.notifier_call          = boost_notify,
565 };
566 
567 /*
568  * acpi_cpufreq_early_init - initialize ACPI P-States library
569  *
570  * Initialize the ACPI P-States library (drivers/acpi/processor_perflib.c)
571  * in order to determine correct frequency and voltage pairings. We can
572  * do _PDC and _PSD and find out the processor dependency for the
573  * actual init that will happen later...
574  */
575 static int __init acpi_cpufreq_early_init(void)
576 {
577 	unsigned int i;
578 	pr_debug("acpi_cpufreq_early_init\n");
579 
580 	acpi_perf_data = alloc_percpu(struct acpi_processor_performance);
581 	if (!acpi_perf_data) {
582 		pr_debug("Memory allocation error for acpi_perf_data.\n");
583 		return -ENOMEM;
584 	}
585 	for_each_possible_cpu(i) {
586 		if (!zalloc_cpumask_var_node(
587 			&per_cpu_ptr(acpi_perf_data, i)->shared_cpu_map,
588 			GFP_KERNEL, cpu_to_node(i))) {
589 
590 			/* Freeing a NULL pointer is OK: alloc_percpu zeroes. */
591 			free_acpi_perf_data();
592 			return -ENOMEM;
593 		}
594 	}
595 
596 	/* Do initialization in ACPI core */
597 	acpi_processor_preregister_performance(acpi_perf_data);
598 	return 0;
599 }
600 
601 #ifdef CONFIG_SMP
602 /*
603  * Some BIOSes do SW_ANY coordination internally, either set it up in hw
604  * or do it in BIOS firmware and won't inform about it to OS. If not
605  * detected, this has a side effect of making CPU run at a different speed
606  * than OS intended it to run at. Detect it and handle it cleanly.
607  */
608 static int bios_with_sw_any_bug;
609 
610 static int sw_any_bug_found(const struct dmi_system_id *d)
611 {
612 	bios_with_sw_any_bug = 1;
613 	return 0;
614 }
615 
616 static const struct dmi_system_id sw_any_bug_dmi_table[] = {
617 	{
618 		.callback = sw_any_bug_found,
619 		.ident = "Supermicro Server X6DLP",
620 		.matches = {
621 			DMI_MATCH(DMI_SYS_VENDOR, "Supermicro"),
622 			DMI_MATCH(DMI_BIOS_VERSION, "080010"),
623 			DMI_MATCH(DMI_PRODUCT_NAME, "X6DLP"),
624 		},
625 	},
626 	{ }
627 };
628 
629 static int acpi_cpufreq_blacklist(struct cpuinfo_x86 *c)
630 {
631 	/* Intel Xeon Processor 7100 Series Specification Update
632 	 * http://www.intel.com/Assets/PDF/specupdate/314554.pdf
633 	 * AL30: A Machine Check Exception (MCE) Occurring during an
634 	 * Enhanced Intel SpeedStep Technology Ratio Change May Cause
635 	 * Both Processor Cores to Lock Up. */
636 	if (c->x86_vendor == X86_VENDOR_INTEL) {
637 		if ((c->x86 == 15) &&
638 		    (c->x86_model == 6) &&
639 		    (c->x86_mask == 8)) {
640 			printk(KERN_INFO "acpi-cpufreq: Intel(R) "
641 			    "Xeon(R) 7100 Errata AL30, processors may "
642 			    "lock up on frequency changes: disabling "
643 			    "acpi-cpufreq.\n");
644 			return -ENODEV;
645 		    }
646 		}
647 	return 0;
648 }
649 #endif
650 
651 static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)
652 {
653 	unsigned int i;
654 	unsigned int valid_states = 0;
655 	unsigned int cpu = policy->cpu;
656 	struct acpi_cpufreq_data *data;
657 	unsigned int result = 0;
658 	struct cpuinfo_x86 *c = &cpu_data(policy->cpu);
659 	struct acpi_processor_performance *perf;
660 #ifdef CONFIG_SMP
661 	static int blacklisted;
662 #endif
663 
664 	pr_debug("acpi_cpufreq_cpu_init\n");
665 
666 #ifdef CONFIG_SMP
667 	if (blacklisted)
668 		return blacklisted;
669 	blacklisted = acpi_cpufreq_blacklist(c);
670 	if (blacklisted)
671 		return blacklisted;
672 #endif
673 
674 	data = kzalloc(sizeof(*data), GFP_KERNEL);
675 	if (!data)
676 		return -ENOMEM;
677 
678 	if (!zalloc_cpumask_var(&data->freqdomain_cpus, GFP_KERNEL)) {
679 		result = -ENOMEM;
680 		goto err_free;
681 	}
682 
683 	perf = per_cpu_ptr(acpi_perf_data, cpu);
684 	data->acpi_perf_cpu = cpu;
685 	policy->driver_data = data;
686 
687 	if (cpu_has(c, X86_FEATURE_CONSTANT_TSC))
688 		acpi_cpufreq_driver.flags |= CPUFREQ_CONST_LOOPS;
689 
690 	result = acpi_processor_register_performance(perf, cpu);
691 	if (result)
692 		goto err_free_mask;
693 
694 	policy->shared_type = perf->shared_type;
695 
696 	/*
697 	 * Will let policy->cpus know about dependency only when software
698 	 * coordination is required.
699 	 */
700 	if (policy->shared_type == CPUFREQ_SHARED_TYPE_ALL ||
701 	    policy->shared_type == CPUFREQ_SHARED_TYPE_ANY) {
702 		cpumask_copy(policy->cpus, perf->shared_cpu_map);
703 	}
704 	cpumask_copy(data->freqdomain_cpus, perf->shared_cpu_map);
705 
706 #ifdef CONFIG_SMP
707 	dmi_check_system(sw_any_bug_dmi_table);
708 	if (bios_with_sw_any_bug && !policy_is_shared(policy)) {
709 		policy->shared_type = CPUFREQ_SHARED_TYPE_ALL;
710 		cpumask_copy(policy->cpus, topology_core_cpumask(cpu));
711 	}
712 
713 	if (check_amd_hwpstate_cpu(cpu) && !acpi_pstate_strict) {
714 		cpumask_clear(policy->cpus);
715 		cpumask_set_cpu(cpu, policy->cpus);
716 		cpumask_copy(data->freqdomain_cpus,
717 			     topology_sibling_cpumask(cpu));
718 		policy->shared_type = CPUFREQ_SHARED_TYPE_HW;
719 		pr_info_once(PFX "overriding BIOS provided _PSD data\n");
720 	}
721 #endif
722 
723 	/* capability check */
724 	if (perf->state_count <= 1) {
725 		pr_debug("No P-States\n");
726 		result = -ENODEV;
727 		goto err_unreg;
728 	}
729 
730 	if (perf->control_register.space_id != perf->status_register.space_id) {
731 		result = -ENODEV;
732 		goto err_unreg;
733 	}
734 
735 	switch (perf->control_register.space_id) {
736 	case ACPI_ADR_SPACE_SYSTEM_IO:
737 		if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
738 		    boot_cpu_data.x86 == 0xf) {
739 			pr_debug("AMD K8 systems must use native drivers.\n");
740 			result = -ENODEV;
741 			goto err_unreg;
742 		}
743 		pr_debug("SYSTEM IO addr space\n");
744 		data->cpu_feature = SYSTEM_IO_CAPABLE;
745 		break;
746 	case ACPI_ADR_SPACE_FIXED_HARDWARE:
747 		pr_debug("HARDWARE addr space\n");
748 		if (check_est_cpu(cpu)) {
749 			data->cpu_feature = SYSTEM_INTEL_MSR_CAPABLE;
750 			break;
751 		}
752 		if (check_amd_hwpstate_cpu(cpu)) {
753 			data->cpu_feature = SYSTEM_AMD_MSR_CAPABLE;
754 			break;
755 		}
756 		result = -ENODEV;
757 		goto err_unreg;
758 	default:
759 		pr_debug("Unknown addr space %d\n",
760 			(u32) (perf->control_register.space_id));
761 		result = -ENODEV;
762 		goto err_unreg;
763 	}
764 
765 	data->freq_table = kzalloc(sizeof(*data->freq_table) *
766 		    (perf->state_count+1), GFP_KERNEL);
767 	if (!data->freq_table) {
768 		result = -ENOMEM;
769 		goto err_unreg;
770 	}
771 
772 	/* detect transition latency */
773 	policy->cpuinfo.transition_latency = 0;
774 	for (i = 0; i < perf->state_count; i++) {
775 		if ((perf->states[i].transition_latency * 1000) >
776 		    policy->cpuinfo.transition_latency)
777 			policy->cpuinfo.transition_latency =
778 			    perf->states[i].transition_latency * 1000;
779 	}
780 
781 	/* Check for high latency (>20uS) from buggy BIOSes, like on T42 */
782 	if (perf->control_register.space_id == ACPI_ADR_SPACE_FIXED_HARDWARE &&
783 	    policy->cpuinfo.transition_latency > 20 * 1000) {
784 		policy->cpuinfo.transition_latency = 20 * 1000;
785 		printk_once(KERN_INFO
786 			    "P-state transition latency capped at 20 uS\n");
787 	}
788 
789 	/* table init */
790 	for (i = 0; i < perf->state_count; i++) {
791 		if (i > 0 && perf->states[i].core_frequency >=
792 		    data->freq_table[valid_states-1].frequency / 1000)
793 			continue;
794 
795 		data->freq_table[valid_states].driver_data = i;
796 		data->freq_table[valid_states].frequency =
797 		    perf->states[i].core_frequency * 1000;
798 		valid_states++;
799 	}
800 	data->freq_table[valid_states].frequency = CPUFREQ_TABLE_END;
801 	perf->state = 0;
802 
803 	result = cpufreq_table_validate_and_show(policy, data->freq_table);
804 	if (result)
805 		goto err_freqfree;
806 
807 	if (perf->states[0].core_frequency * 1000 != policy->cpuinfo.max_freq)
808 		printk(KERN_WARNING FW_WARN "P-state 0 is not max freq\n");
809 
810 	switch (perf->control_register.space_id) {
811 	case ACPI_ADR_SPACE_SYSTEM_IO:
812 		/*
813 		 * The core will not set policy->cur, because
814 		 * cpufreq_driver->get is NULL, so we need to set it here.
815 		 * However, we have to guess it, because the current speed is
816 		 * unknown and not detectable via IO ports.
817 		 */
818 		policy->cur = acpi_cpufreq_guess_freq(data, policy->cpu);
819 		break;
820 	case ACPI_ADR_SPACE_FIXED_HARDWARE:
821 		acpi_cpufreq_driver.get = get_cur_freq_on_cpu;
822 		break;
823 	default:
824 		break;
825 	}
826 
827 	/* notify BIOS that we exist */
828 	acpi_processor_notify_smm(THIS_MODULE);
829 
830 	pr_debug("CPU%u - ACPI performance management activated.\n", cpu);
831 	for (i = 0; i < perf->state_count; i++)
832 		pr_debug("     %cP%d: %d MHz, %d mW, %d uS\n",
833 			(i == perf->state ? '*' : ' '), i,
834 			(u32) perf->states[i].core_frequency,
835 			(u32) perf->states[i].power,
836 			(u32) perf->states[i].transition_latency);
837 
838 	/*
839 	 * the first call to ->target() should result in us actually
840 	 * writing something to the appropriate registers.
841 	 */
842 	data->resume = 1;
843 
844 	return result;
845 
846 err_freqfree:
847 	kfree(data->freq_table);
848 err_unreg:
849 	acpi_processor_unregister_performance(cpu);
850 err_free_mask:
851 	free_cpumask_var(data->freqdomain_cpus);
852 err_free:
853 	kfree(data);
854 	policy->driver_data = NULL;
855 
856 	return result;
857 }
858 
859 static int acpi_cpufreq_cpu_exit(struct cpufreq_policy *policy)
860 {
861 	struct acpi_cpufreq_data *data = policy->driver_data;
862 
863 	pr_debug("acpi_cpufreq_cpu_exit\n");
864 
865 	if (data) {
866 		policy->driver_data = NULL;
867 		acpi_processor_unregister_performance(data->acpi_perf_cpu);
868 		free_cpumask_var(data->freqdomain_cpus);
869 		kfree(data->freq_table);
870 		kfree(data);
871 	}
872 
873 	return 0;
874 }
875 
876 static int acpi_cpufreq_resume(struct cpufreq_policy *policy)
877 {
878 	struct acpi_cpufreq_data *data = policy->driver_data;
879 
880 	pr_debug("acpi_cpufreq_resume\n");
881 
882 	data->resume = 1;
883 
884 	return 0;
885 }
886 
887 static struct freq_attr *acpi_cpufreq_attr[] = {
888 	&cpufreq_freq_attr_scaling_available_freqs,
889 	&freqdomain_cpus,
890 #ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
891 	&cpb,
892 #endif
893 	NULL,
894 };
895 
896 static struct cpufreq_driver acpi_cpufreq_driver = {
897 	.verify		= cpufreq_generic_frequency_table_verify,
898 	.target_index	= acpi_cpufreq_target,
899 	.bios_limit	= acpi_processor_get_bios_limit,
900 	.init		= acpi_cpufreq_cpu_init,
901 	.exit		= acpi_cpufreq_cpu_exit,
902 	.resume		= acpi_cpufreq_resume,
903 	.name		= "acpi-cpufreq",
904 	.attr		= acpi_cpufreq_attr,
905 	.set_boost      = _store_boost,
906 };
907 
908 static void __init acpi_cpufreq_boost_init(void)
909 {
910 	if (boot_cpu_has(X86_FEATURE_CPB) || boot_cpu_has(X86_FEATURE_IDA)) {
911 		msrs = msrs_alloc();
912 
913 		if (!msrs)
914 			return;
915 
916 		acpi_cpufreq_driver.boost_supported = true;
917 		acpi_cpufreq_driver.boost_enabled = boost_state(0);
918 
919 		cpu_notifier_register_begin();
920 
921 		/* Force all MSRs to the same value */
922 		boost_set_msrs(acpi_cpufreq_driver.boost_enabled,
923 			       cpu_online_mask);
924 
925 		__register_cpu_notifier(&boost_nb);
926 
927 		cpu_notifier_register_done();
928 	}
929 }
930 
931 static void acpi_cpufreq_boost_exit(void)
932 {
933 	if (msrs) {
934 		unregister_cpu_notifier(&boost_nb);
935 
936 		msrs_free(msrs);
937 		msrs = NULL;
938 	}
939 }
940 
941 static int __init acpi_cpufreq_init(void)
942 {
943 	int ret;
944 
945 	if (acpi_disabled)
946 		return -ENODEV;
947 
948 	/* don't keep reloading if cpufreq_driver exists */
949 	if (cpufreq_get_current_driver())
950 		return -EEXIST;
951 
952 	pr_debug("acpi_cpufreq_init\n");
953 
954 	ret = acpi_cpufreq_early_init();
955 	if (ret)
956 		return ret;
957 
958 #ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
959 	/* this is a sysfs file with a strange name and an even stranger
960 	 * semantic - per CPU instantiation, but system global effect.
961 	 * Lets enable it only on AMD CPUs for compatibility reasons and
962 	 * only if configured. This is considered legacy code, which
963 	 * will probably be removed at some point in the future.
964 	 */
965 	if (!check_amd_hwpstate_cpu(0)) {
966 		struct freq_attr **attr;
967 
968 		pr_debug("CPB unsupported, do not expose it\n");
969 
970 		for (attr = acpi_cpufreq_attr; *attr; attr++)
971 			if (*attr == &cpb) {
972 				*attr = NULL;
973 				break;
974 			}
975 	}
976 #endif
977 	acpi_cpufreq_boost_init();
978 
979 	ret = cpufreq_register_driver(&acpi_cpufreq_driver);
980 	if (ret) {
981 		free_acpi_perf_data();
982 		acpi_cpufreq_boost_exit();
983 	}
984 	return ret;
985 }
986 
987 static void __exit acpi_cpufreq_exit(void)
988 {
989 	pr_debug("acpi_cpufreq_exit\n");
990 
991 	acpi_cpufreq_boost_exit();
992 
993 	cpufreq_unregister_driver(&acpi_cpufreq_driver);
994 
995 	free_acpi_perf_data();
996 }
997 
998 module_param(acpi_pstate_strict, uint, 0644);
999 MODULE_PARM_DESC(acpi_pstate_strict,
1000 	"value 0 or non-zero. non-zero -> strict ACPI checks are "
1001 	"performed during frequency changes.");
1002 
1003 late_initcall(acpi_cpufreq_init);
1004 module_exit(acpi_cpufreq_exit);
1005 
1006 static const struct x86_cpu_id acpi_cpufreq_ids[] = {
1007 	X86_FEATURE_MATCH(X86_FEATURE_ACPI),
1008 	X86_FEATURE_MATCH(X86_FEATURE_HW_PSTATE),
1009 	{}
1010 };
1011 MODULE_DEVICE_TABLE(x86cpu, acpi_cpufreq_ids);
1012 
1013 static const struct acpi_device_id processor_device_ids[] = {
1014 	{ACPI_PROCESSOR_OBJECT_HID, },
1015 	{ACPI_PROCESSOR_DEVICE_HID, },
1016 	{},
1017 };
1018 MODULE_DEVICE_TABLE(acpi, processor_device_ids);
1019 
1020 MODULE_ALIAS("acpi");
1021