2 * processor_perflib.c - ACPI Processor P-States Library ($Revision: 71 $)
8 * - Added processor hotplug support
11 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
13 * This program is free software; you can redistribute it and/or modify
14 * it under the terms of the GNU General Public License as published by
15 * the Free Software Foundation; either version 2 of the License, or (at
16 * your option) any later version.
18 * This program is distributed in the hope that it will be useful, but
19 * WITHOUT ANY WARRANTY; without even the implied warranty of
20 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
21 * General Public License for more details.
25 #include <linux/kernel.h>
26 #include <linux/module.h>
27 #include <linux/init.h>
28 #include <linux/cpufreq.h>
29 #include <linux/slab.h>
30 #include <linux/acpi.h>
31 #include <acpi/processor.h>
33 #include <asm/cpufeature.h>
36 #define PREFIX "ACPI: "
38 #define ACPI_PROCESSOR_CLASS "processor"
39 #define ACPI_PROCESSOR_FILE_PERFORMANCE "performance"
40 #define _COMPONENT ACPI_PROCESSOR_COMPONENT
41 ACPI_MODULE_NAME("processor_perflib");
43 static DEFINE_MUTEX(performance_mutex);
46 * _PPC support is implemented as a CPUfreq policy notifier:
47 * This means each time a CPUfreq driver registered also with
48 * the ACPI core is asked to change the speed policy, the maximum
49 * value is adjusted so that it is within the platform limit.
51 * Also, when a new platform limit value is detected, the CPUfreq
52 * policy is adjusted accordingly.
56 * -1 -> cpufreq low level drivers not initialized -> _PSS, etc. not called yet
58 * 0 -> cpufreq low level drivers initialized -> consider _PPC values
59 * 1 -> ignore _PPC totally -> forced by user through boot param
61 static int ignore_ppc = -1;
62 module_param(ignore_ppc, int, 0644);
63 MODULE_PARM_DESC(ignore_ppc, "If the frequency of your machine gets wrongly" \
64 "limited by BIOS, this should help");
66 #define PPC_REGISTERED 1
69 static int acpi_processor_ppc_status;
71 static int acpi_processor_ppc_notifier(struct notifier_block *nb,
72 unsigned long event, void *data)
74 struct cpufreq_policy *policy = data;
75 struct acpi_processor *pr;
78 if (event == CPUFREQ_START && ignore_ppc <= 0) {
86 if (event != CPUFREQ_ADJUST)
89 mutex_lock(&performance_mutex);
91 pr = per_cpu(processors, policy->cpu);
92 if (!pr || !pr->performance)
95 ppc = (unsigned int)pr->performance_platform_limit;
97 if (ppc >= pr->performance->state_count)
100 cpufreq_verify_within_limits(policy, 0,
101 pr->performance->states[ppc].
102 core_frequency * 1000);
105 mutex_unlock(&performance_mutex);
110 static struct notifier_block acpi_ppc_notifier_block = {
111 .notifier_call = acpi_processor_ppc_notifier,
114 static int acpi_processor_get_platform_limit(struct acpi_processor *pr)
116 acpi_status status = 0;
117 unsigned long long ppc = 0;
124 * _PPC indicates the maximum state currently supported by the platform
125 * (e.g. 0 = states 0..n; 1 = states 1..n; etc.
127 status = acpi_evaluate_integer(pr->handle, "_PPC", NULL, &ppc);
129 if (status != AE_NOT_FOUND)
130 acpi_processor_ppc_status |= PPC_IN_USE;
132 if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
133 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PPC"));
137 pr_debug("CPU %d: _PPC is %d - frequency %s limited\n", pr->id,
138 (int)ppc, ppc ? "" : "not");
140 pr->performance_platform_limit = (int)ppc;
145 #define ACPI_PROCESSOR_NOTIFY_PERFORMANCE 0x80
147 * acpi_processor_ppc_ost: Notify firmware the _PPC evaluation status
148 * @handle: ACPI processor handle
149 * @status: the status code of _PPC evaluation
150 * 0: success. OSPM is now using the performance state specificed.
151 * 1: failure. OSPM has not changed the number of P-states in use
153 static void acpi_processor_ppc_ost(acpi_handle handle, int status)
155 if (acpi_has_method(handle, "_OST"))
156 acpi_evaluate_ost(handle, ACPI_PROCESSOR_NOTIFY_PERFORMANCE,
160 void acpi_processor_ppc_has_changed(struct acpi_processor *pr, int event_flag)
166 * Only when it is notification event, the _OST object
167 * will be evaluated. Otherwise it is skipped.
170 acpi_processor_ppc_ost(pr->handle, 1);
174 ret = acpi_processor_get_platform_limit(pr);
176 * Only when it is notification event, the _OST object
177 * will be evaluated. Otherwise it is skipped.
181 acpi_processor_ppc_ost(pr->handle, 1);
183 acpi_processor_ppc_ost(pr->handle, 0);
186 cpufreq_update_policy(pr->id);
189 int acpi_processor_get_bios_limit(int cpu, unsigned int *limit)
191 struct acpi_processor *pr;
193 pr = per_cpu(processors, cpu);
194 if (!pr || !pr->performance || !pr->performance->state_count)
196 *limit = pr->performance->states[pr->performance_platform_limit].
197 core_frequency * 1000;
200 EXPORT_SYMBOL(acpi_processor_get_bios_limit);
202 void acpi_processor_ppc_init(void)
204 if (!cpufreq_register_notifier
205 (&acpi_ppc_notifier_block, CPUFREQ_POLICY_NOTIFIER))
206 acpi_processor_ppc_status |= PPC_REGISTERED;
209 "Warning: Processor Platform Limit not supported.\n");
212 void acpi_processor_ppc_exit(void)
214 if (acpi_processor_ppc_status & PPC_REGISTERED)
215 cpufreq_unregister_notifier(&acpi_ppc_notifier_block,
216 CPUFREQ_POLICY_NOTIFIER);
218 acpi_processor_ppc_status &= ~PPC_REGISTERED;
221 static int acpi_processor_get_performance_control(struct acpi_processor *pr)
224 acpi_status status = 0;
225 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
226 union acpi_object *pct = NULL;
227 union acpi_object obj = { 0 };
230 status = acpi_evaluate_object(pr->handle, "_PCT", NULL, &buffer);
231 if (ACPI_FAILURE(status)) {
232 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PCT"));
236 pct = (union acpi_object *)buffer.pointer;
237 if (!pct || (pct->type != ACPI_TYPE_PACKAGE)
238 || (pct->package.count != 2)) {
239 printk(KERN_ERR PREFIX "Invalid _PCT data\n");
248 obj = pct->package.elements[0];
250 if ((obj.type != ACPI_TYPE_BUFFER)
251 || (obj.buffer.length < sizeof(struct acpi_pct_register))
252 || (obj.buffer.pointer == NULL)) {
253 printk(KERN_ERR PREFIX "Invalid _PCT data (control_register)\n");
257 memcpy(&pr->performance->control_register, obj.buffer.pointer,
258 sizeof(struct acpi_pct_register));
264 obj = pct->package.elements[1];
266 if ((obj.type != ACPI_TYPE_BUFFER)
267 || (obj.buffer.length < sizeof(struct acpi_pct_register))
268 || (obj.buffer.pointer == NULL)) {
269 printk(KERN_ERR PREFIX "Invalid _PCT data (status_register)\n");
274 memcpy(&pr->performance->status_register, obj.buffer.pointer,
275 sizeof(struct acpi_pct_register));
278 kfree(buffer.pointer);
285 * Some AMDs have 50MHz frequency multiples, but only provide 100MHz rounding
286 * in their ACPI data. Calculate the real values and fix up the _PSS data.
288 static void amd_fixup_frequency(struct acpi_processor_px *px, int i)
290 u32 hi, lo, fid, did;
291 int index = px->control & 0x00000007;
293 if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD)
296 if ((boot_cpu_data.x86 == 0x10 && boot_cpu_data.x86_model < 10)
297 || boot_cpu_data.x86 == 0x11) {
298 rdmsr(MSR_AMD_PSTATE_DEF_BASE + index, lo, hi);
301 * Bit 63: PstateEn. Read-write. If set, the P-state is valid.
308 if (boot_cpu_data.x86 == 0x10)
309 px->core_frequency = (100 * (fid + 0x10)) >> did;
311 px->core_frequency = (100 * (fid + 8)) >> did;
315 static void amd_fixup_frequency(struct acpi_processor_px *px, int i) {};
318 static int acpi_processor_get_performance_states(struct acpi_processor *pr)
321 acpi_status status = AE_OK;
322 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
323 struct acpi_buffer format = { sizeof("NNNNNN"), "NNNNNN" };
324 struct acpi_buffer state = { 0, NULL };
325 union acpi_object *pss = NULL;
327 int last_invalid = -1;
330 status = acpi_evaluate_object(pr->handle, "_PSS", NULL, &buffer);
331 if (ACPI_FAILURE(status)) {
332 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PSS"));
336 pss = buffer.pointer;
337 if (!pss || (pss->type != ACPI_TYPE_PACKAGE)) {
338 printk(KERN_ERR PREFIX "Invalid _PSS data\n");
343 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d performance states\n",
344 pss->package.count));
346 pr->performance->state_count = pss->package.count;
347 pr->performance->states =
348 kmalloc(sizeof(struct acpi_processor_px) * pss->package.count,
350 if (!pr->performance->states) {
355 for (i = 0; i < pr->performance->state_count; i++) {
357 struct acpi_processor_px *px = &(pr->performance->states[i]);
359 state.length = sizeof(struct acpi_processor_px);
362 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Extracting state %d\n", i));
364 status = acpi_extract_package(&(pss->package.elements[i]),
366 if (ACPI_FAILURE(status)) {
367 ACPI_EXCEPTION((AE_INFO, status, "Invalid _PSS data"));
369 kfree(pr->performance->states);
373 amd_fixup_frequency(px, i);
375 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
376 "State [%d]: core_frequency[%d] power[%d] transition_latency[%d] bus_master_latency[%d] control[0x%x] status[0x%x]\n",
378 (u32) px->core_frequency,
380 (u32) px->transition_latency,
381 (u32) px->bus_master_latency,
382 (u32) px->control, (u32) px->status));
385 * Check that ACPI's u64 MHz will be valid as u32 KHz in cpufreq
387 if (!px->core_frequency ||
388 ((u32)(px->core_frequency * 1000) !=
389 (px->core_frequency * 1000))) {
390 printk(KERN_ERR FW_BUG PREFIX
391 "Invalid BIOS _PSS frequency found for processor %d: 0x%llx MHz\n",
392 pr->id, px->core_frequency);
393 if (last_invalid == -1)
396 if (last_invalid != -1) {
398 * Copy this valid entry over last_invalid entry
400 memcpy(&(pr->performance->states[last_invalid]),
401 px, sizeof(struct acpi_processor_px));
407 if (last_invalid == 0) {
408 printk(KERN_ERR FW_BUG PREFIX
409 "No valid BIOS _PSS frequency found for processor %d\n", pr->id);
411 kfree(pr->performance->states);
412 pr->performance->states = NULL;
415 if (last_invalid > 0)
416 pr->performance->state_count = last_invalid;
419 kfree(buffer.pointer);
424 int acpi_processor_get_performance_info(struct acpi_processor *pr)
428 if (!pr || !pr->performance || !pr->handle)
431 if (!acpi_has_method(pr->handle, "_PCT")) {
432 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
433 "ACPI-based processor performance control unavailable\n"));
437 result = acpi_processor_get_performance_control(pr);
441 result = acpi_processor_get_performance_states(pr);
445 /* We need to call _PPC once when cpufreq starts */
447 result = acpi_processor_get_platform_limit(pr);
452 * Having _PPC but missing frequencies (_PSS, _PCT) is a very good hint that
453 * the BIOS is older than the CPU and does not know its frequencies
457 if (acpi_has_method(pr->handle, "_PPC")) {
458 if(boot_cpu_has(X86_FEATURE_EST))
459 printk(KERN_WARNING FW_BUG "BIOS needs update for CPU "
460 "frequency support\n");
465 EXPORT_SYMBOL_GPL(acpi_processor_get_performance_info);
467 int acpi_processor_pstate_control(void)
471 if (!acpi_gbl_FADT.smi_command || !acpi_gbl_FADT.pstate_control)
474 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
475 "Writing pstate_control [0x%x] to smi_command [0x%x]\n",
476 acpi_gbl_FADT.pstate_control, acpi_gbl_FADT.smi_command));
478 status = acpi_os_write_port(acpi_gbl_FADT.smi_command,
479 (u32)acpi_gbl_FADT.pstate_control, 8);
480 if (ACPI_SUCCESS(status))
483 ACPI_EXCEPTION((AE_INFO, status,
484 "Failed to write pstate_control [0x%x] to smi_command [0x%x]",
485 acpi_gbl_FADT.pstate_control, acpi_gbl_FADT.smi_command));
489 int acpi_processor_notify_smm(struct module *calling_module)
491 static int is_done = 0;
494 if (!(acpi_processor_ppc_status & PPC_REGISTERED))
497 if (!try_module_get(calling_module))
500 /* is_done is set to negative if an error occurred,
501 * and to postitive if _no_ error occurred, but SMM
502 * was already notified. This avoids double notification
503 * which might lead to unexpected results...
506 module_put(calling_module);
508 } else if (is_done < 0) {
509 module_put(calling_module);
515 result = acpi_processor_pstate_control();
517 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No SMI port or pstate_control\n"));
518 module_put(calling_module);
522 module_put(calling_module);
526 /* Success. If there's no _PPC, we need to fear nothing, so
527 * we can allow the cpufreq driver to be rmmod'ed. */
530 if (!(acpi_processor_ppc_status & PPC_IN_USE))
531 module_put(calling_module);
536 EXPORT_SYMBOL(acpi_processor_notify_smm);
538 static int acpi_processor_get_psd(struct acpi_processor *pr)
541 acpi_status status = AE_OK;
542 struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
543 struct acpi_buffer format = {sizeof("NNNNN"), "NNNNN"};
544 struct acpi_buffer state = {0, NULL};
545 union acpi_object *psd = NULL;
546 struct acpi_psd_package *pdomain;
548 status = acpi_evaluate_object(pr->handle, "_PSD", NULL, &buffer);
549 if (ACPI_FAILURE(status)) {
553 psd = buffer.pointer;
554 if (!psd || (psd->type != ACPI_TYPE_PACKAGE)) {
555 printk(KERN_ERR PREFIX "Invalid _PSD data\n");
560 if (psd->package.count != 1) {
561 printk(KERN_ERR PREFIX "Invalid _PSD data\n");
566 pdomain = &(pr->performance->domain_info);
568 state.length = sizeof(struct acpi_psd_package);
569 state.pointer = pdomain;
571 status = acpi_extract_package(&(psd->package.elements[0]),
573 if (ACPI_FAILURE(status)) {
574 printk(KERN_ERR PREFIX "Invalid _PSD data\n");
579 if (pdomain->num_entries != ACPI_PSD_REV0_ENTRIES) {
580 printk(KERN_ERR PREFIX "Unknown _PSD:num_entries\n");
585 if (pdomain->revision != ACPI_PSD_REV0_REVISION) {
586 printk(KERN_ERR PREFIX "Unknown _PSD:revision\n");
591 if (pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ALL &&
592 pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ANY &&
593 pdomain->coord_type != DOMAIN_COORD_TYPE_HW_ALL) {
594 printk(KERN_ERR PREFIX "Invalid _PSD:coord_type\n");
599 kfree(buffer.pointer);
603 int acpi_processor_preregister_performance(
604 struct acpi_processor_performance __percpu *performance)
609 cpumask_var_t covered_cpus;
610 struct acpi_processor *pr;
611 struct acpi_psd_package *pdomain;
612 struct acpi_processor *match_pr;
613 struct acpi_psd_package *match_pdomain;
615 if (!zalloc_cpumask_var(&covered_cpus, GFP_KERNEL))
618 mutex_lock(&performance_mutex);
621 * Check if another driver has already registered, and abort before
622 * changing pr->performance if it has. Check input data as well.
624 for_each_possible_cpu(i) {
625 pr = per_cpu(processors, i);
627 /* Look only at processors in ACPI namespace */
631 if (pr->performance) {
636 if (!performance || !per_cpu_ptr(performance, i)) {
642 /* Call _PSD for all CPUs */
643 for_each_possible_cpu(i) {
644 pr = per_cpu(processors, i);
648 pr->performance = per_cpu_ptr(performance, i);
649 cpumask_set_cpu(i, pr->performance->shared_cpu_map);
650 if (acpi_processor_get_psd(pr)) {
659 * Now that we have _PSD data from all CPUs, lets setup P-state
662 for_each_possible_cpu(i) {
663 pr = per_cpu(processors, i);
667 if (cpumask_test_cpu(i, covered_cpus))
670 pdomain = &(pr->performance->domain_info);
671 cpumask_set_cpu(i, pr->performance->shared_cpu_map);
672 cpumask_set_cpu(i, covered_cpus);
673 if (pdomain->num_processors <= 1)
676 /* Validate the Domain info */
677 count_target = pdomain->num_processors;
678 if (pdomain->coord_type == DOMAIN_COORD_TYPE_SW_ALL)
679 pr->performance->shared_type = CPUFREQ_SHARED_TYPE_ALL;
680 else if (pdomain->coord_type == DOMAIN_COORD_TYPE_HW_ALL)
681 pr->performance->shared_type = CPUFREQ_SHARED_TYPE_HW;
682 else if (pdomain->coord_type == DOMAIN_COORD_TYPE_SW_ANY)
683 pr->performance->shared_type = CPUFREQ_SHARED_TYPE_ANY;
685 for_each_possible_cpu(j) {
689 match_pr = per_cpu(processors, j);
693 match_pdomain = &(match_pr->performance->domain_info);
694 if (match_pdomain->domain != pdomain->domain)
697 /* Here i and j are in the same domain */
699 if (match_pdomain->num_processors != count_target) {
704 if (pdomain->coord_type != match_pdomain->coord_type) {
709 cpumask_set_cpu(j, covered_cpus);
710 cpumask_set_cpu(j, pr->performance->shared_cpu_map);
713 for_each_possible_cpu(j) {
717 match_pr = per_cpu(processors, j);
721 match_pdomain = &(match_pr->performance->domain_info);
722 if (match_pdomain->domain != pdomain->domain)
725 match_pr->performance->shared_type =
726 pr->performance->shared_type;
727 cpumask_copy(match_pr->performance->shared_cpu_map,
728 pr->performance->shared_cpu_map);
733 for_each_possible_cpu(i) {
734 pr = per_cpu(processors, i);
735 if (!pr || !pr->performance)
738 /* Assume no coordination on any error parsing domain info */
740 cpumask_clear(pr->performance->shared_cpu_map);
741 cpumask_set_cpu(i, pr->performance->shared_cpu_map);
742 pr->performance->shared_type = CPUFREQ_SHARED_TYPE_ALL;
744 pr->performance = NULL; /* Will be set for real in register */
748 mutex_unlock(&performance_mutex);
749 free_cpumask_var(covered_cpus);
752 EXPORT_SYMBOL(acpi_processor_preregister_performance);
755 acpi_processor_register_performance(struct acpi_processor_performance
756 *performance, unsigned int cpu)
758 struct acpi_processor *pr;
760 if (!(acpi_processor_ppc_status & PPC_REGISTERED))
763 mutex_lock(&performance_mutex);
765 pr = per_cpu(processors, cpu);
767 mutex_unlock(&performance_mutex);
771 if (pr->performance) {
772 mutex_unlock(&performance_mutex);
776 WARN_ON(!performance);
778 pr->performance = performance;
780 if (acpi_processor_get_performance_info(pr)) {
781 pr->performance = NULL;
782 mutex_unlock(&performance_mutex);
786 mutex_unlock(&performance_mutex);
790 EXPORT_SYMBOL(acpi_processor_register_performance);
792 void acpi_processor_unregister_performance(unsigned int cpu)
794 struct acpi_processor *pr;
796 mutex_lock(&performance_mutex);
798 pr = per_cpu(processors, cpu);
800 mutex_unlock(&performance_mutex);
805 kfree(pr->performance->states);
806 pr->performance = NULL;
808 mutex_unlock(&performance_mutex);
813 EXPORT_SYMBOL(acpi_processor_unregister_performance);