2 * processor_perflib.c - ACPI Processor P-States Library ($Revision: 71 $)
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) 2004 Dominik Brodowski <linux@brodo.de>
7 * Copyright (C) 2004 Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
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.
23 * You should have received a copy of the GNU General Public License along
24 * with this program; if not, write to the Free Software Foundation, Inc.,
25 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
29 #include <linux/kernel.h>
30 #include <linux/module.h>
31 #include <linux/init.h>
32 #include <linux/cpufreq.h>
33 #include <linux/slab.h>
36 #include <asm/cpufeature.h>
39 #include <acpi/acpi_bus.h>
40 #include <acpi/acpi_drivers.h>
41 #include <acpi/processor.h>
43 #define PREFIX "ACPI: "
45 #define ACPI_PROCESSOR_CLASS "processor"
46 #define ACPI_PROCESSOR_FILE_PERFORMANCE "performance"
47 #define _COMPONENT ACPI_PROCESSOR_COMPONENT
48 ACPI_MODULE_NAME("processor_perflib");
50 static DEFINE_MUTEX(performance_mutex);
52 /* Use cpufreq debug layer for _PPC changes. */
53 #define cpufreq_printk(msg...) cpufreq_debug_printk(CPUFREQ_DEBUG_CORE, \
57 * _PPC support is implemented as a CPUfreq policy notifier:
58 * This means each time a CPUfreq driver registered also with
59 * the ACPI core is asked to change the speed policy, the maximum
60 * value is adjusted so that it is within the platform limit.
62 * Also, when a new platform limit value is detected, the CPUfreq
63 * policy is adjusted accordingly.
67 * -1 -> cpufreq low level drivers not initialized -> _PSS, etc. not called yet
69 * 0 -> cpufreq low level drivers initialized -> consider _PPC values
70 * 1 -> ignore _PPC totally -> forced by user through boot param
72 static int ignore_ppc = -1;
73 module_param(ignore_ppc, int, 0644);
74 MODULE_PARM_DESC(ignore_ppc, "If the frequency of your machine gets wrongly" \
75 "limited by BIOS, this should help");
77 #define PPC_REGISTERED 1
80 static int acpi_processor_ppc_status;
82 static int acpi_processor_ppc_notifier(struct notifier_block *nb,
83 unsigned long event, void *data)
85 struct cpufreq_policy *policy = data;
86 struct acpi_processor *pr;
89 if (event == CPUFREQ_START && ignore_ppc <= 0) {
97 if (event != CPUFREQ_INCOMPATIBLE)
100 mutex_lock(&performance_mutex);
102 pr = per_cpu(processors, policy->cpu);
103 if (!pr || !pr->performance)
106 ppc = (unsigned int)pr->performance_platform_limit;
108 if (ppc >= pr->performance->state_count)
111 cpufreq_verify_within_limits(policy, 0,
112 pr->performance->states[ppc].
113 core_frequency * 1000);
116 mutex_unlock(&performance_mutex);
121 static struct notifier_block acpi_ppc_notifier_block = {
122 .notifier_call = acpi_processor_ppc_notifier,
125 static int acpi_processor_get_platform_limit(struct acpi_processor *pr)
127 acpi_status status = 0;
128 unsigned long long ppc = 0;
135 * _PPC indicates the maximum state currently supported by the platform
136 * (e.g. 0 = states 0..n; 1 = states 1..n; etc.
138 status = acpi_evaluate_integer(pr->handle, "_PPC", NULL, &ppc);
140 if (status != AE_NOT_FOUND)
141 acpi_processor_ppc_status |= PPC_IN_USE;
143 if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
144 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PPC"));
148 cpufreq_printk("CPU %d: _PPC is %d - frequency %s limited\n", pr->id,
149 (int)ppc, ppc ? "" : "not");
151 pr->performance_platform_limit = (int)ppc;
156 #define ACPI_PROCESSOR_NOTIFY_PERFORMANCE 0x80
158 * acpi_processor_ppc_ost: Notify firmware the _PPC evaluation status
159 * @handle: ACPI processor handle
160 * @status: the status code of _PPC evaluation
161 * 0: success. OSPM is now using the performance state specificed.
162 * 1: failure. OSPM has not changed the number of P-states in use
164 static void acpi_processor_ppc_ost(acpi_handle handle, int status)
166 union acpi_object params[2] = {
167 {.type = ACPI_TYPE_INTEGER,},
168 {.type = ACPI_TYPE_INTEGER,},
170 struct acpi_object_list arg_list = {2, params};
173 params[0].integer.value = ACPI_PROCESSOR_NOTIFY_PERFORMANCE;
174 params[1].integer.value = status;
176 /* when there is no _OST , skip it */
177 if (ACPI_FAILURE(acpi_get_handle(handle, "_OST", &temp)))
180 acpi_evaluate_object(handle, "_OST", &arg_list, NULL);
184 int acpi_processor_ppc_has_changed(struct acpi_processor *pr, int event_flag)
190 * Only when it is notification event, the _OST object
191 * will be evaluated. Otherwise it is skipped.
194 acpi_processor_ppc_ost(pr->handle, 1);
198 ret = acpi_processor_get_platform_limit(pr);
200 * Only when it is notification event, the _OST object
201 * will be evaluated. Otherwise it is skipped.
205 acpi_processor_ppc_ost(pr->handle, 1);
207 acpi_processor_ppc_ost(pr->handle, 0);
212 return cpufreq_update_policy(pr->id);
215 int acpi_processor_get_bios_limit(int cpu, unsigned int *limit)
217 struct acpi_processor *pr;
219 pr = per_cpu(processors, cpu);
220 if (!pr || !pr->performance || !pr->performance->state_count)
222 *limit = pr->performance->states[pr->performance_platform_limit].
223 core_frequency * 1000;
226 EXPORT_SYMBOL(acpi_processor_get_bios_limit);
228 void acpi_processor_ppc_init(void)
230 if (!cpufreq_register_notifier
231 (&acpi_ppc_notifier_block, CPUFREQ_POLICY_NOTIFIER))
232 acpi_processor_ppc_status |= PPC_REGISTERED;
235 "Warning: Processor Platform Limit not supported.\n");
238 void acpi_processor_ppc_exit(void)
240 if (acpi_processor_ppc_status & PPC_REGISTERED)
241 cpufreq_unregister_notifier(&acpi_ppc_notifier_block,
242 CPUFREQ_POLICY_NOTIFIER);
244 acpi_processor_ppc_status &= ~PPC_REGISTERED;
247 static int acpi_processor_get_performance_control(struct acpi_processor *pr)
250 acpi_status status = 0;
251 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
252 union acpi_object *pct = NULL;
253 union acpi_object obj = { 0 };
256 status = acpi_evaluate_object(pr->handle, "_PCT", NULL, &buffer);
257 if (ACPI_FAILURE(status)) {
258 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PCT"));
262 pct = (union acpi_object *)buffer.pointer;
263 if (!pct || (pct->type != ACPI_TYPE_PACKAGE)
264 || (pct->package.count != 2)) {
265 printk(KERN_ERR PREFIX "Invalid _PCT data\n");
274 obj = pct->package.elements[0];
276 if ((obj.type != ACPI_TYPE_BUFFER)
277 || (obj.buffer.length < sizeof(struct acpi_pct_register))
278 || (obj.buffer.pointer == NULL)) {
279 printk(KERN_ERR PREFIX "Invalid _PCT data (control_register)\n");
283 memcpy(&pr->performance->control_register, obj.buffer.pointer,
284 sizeof(struct acpi_pct_register));
290 obj = pct->package.elements[1];
292 if ((obj.type != ACPI_TYPE_BUFFER)
293 || (obj.buffer.length < sizeof(struct acpi_pct_register))
294 || (obj.buffer.pointer == NULL)) {
295 printk(KERN_ERR PREFIX "Invalid _PCT data (status_register)\n");
300 memcpy(&pr->performance->status_register, obj.buffer.pointer,
301 sizeof(struct acpi_pct_register));
304 kfree(buffer.pointer);
309 static int acpi_processor_get_performance_states(struct acpi_processor *pr)
312 acpi_status status = AE_OK;
313 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
314 struct acpi_buffer format = { sizeof("NNNNNN"), "NNNNNN" };
315 struct acpi_buffer state = { 0, NULL };
316 union acpi_object *pss = NULL;
320 status = acpi_evaluate_object(pr->handle, "_PSS", NULL, &buffer);
321 if (ACPI_FAILURE(status)) {
322 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PSS"));
326 pss = buffer.pointer;
327 if (!pss || (pss->type != ACPI_TYPE_PACKAGE)) {
328 printk(KERN_ERR PREFIX "Invalid _PSS data\n");
333 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d performance states\n",
334 pss->package.count));
336 pr->performance->state_count = pss->package.count;
337 pr->performance->states =
338 kmalloc(sizeof(struct acpi_processor_px) * pss->package.count,
340 if (!pr->performance->states) {
345 for (i = 0; i < pr->performance->state_count; i++) {
347 struct acpi_processor_px *px = &(pr->performance->states[i]);
349 state.length = sizeof(struct acpi_processor_px);
352 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Extracting state %d\n", i));
354 status = acpi_extract_package(&(pss->package.elements[i]),
356 if (ACPI_FAILURE(status)) {
357 ACPI_EXCEPTION((AE_INFO, status, "Invalid _PSS data"));
359 kfree(pr->performance->states);
363 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
364 "State [%d]: core_frequency[%d] power[%d] transition_latency[%d] bus_master_latency[%d] control[0x%x] status[0x%x]\n",
366 (u32) px->core_frequency,
368 (u32) px->transition_latency,
369 (u32) px->bus_master_latency,
370 (u32) px->control, (u32) px->status));
373 * Check that ACPI's u64 MHz will be valid as u32 KHz in cpufreq
375 if (!px->core_frequency ||
376 ((u32)(px->core_frequency * 1000) !=
377 (px->core_frequency * 1000))) {
378 printk(KERN_ERR FW_BUG PREFIX
379 "Invalid BIOS _PSS frequency: 0x%llx MHz\n",
382 kfree(pr->performance->states);
388 kfree(buffer.pointer);
393 static int acpi_processor_get_performance_info(struct acpi_processor *pr)
396 acpi_status status = AE_OK;
397 acpi_handle handle = NULL;
399 if (!pr || !pr->performance || !pr->handle)
402 status = acpi_get_handle(pr->handle, "_PCT", &handle);
403 if (ACPI_FAILURE(status)) {
404 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
405 "ACPI-based processor performance control unavailable\n"));
409 result = acpi_processor_get_performance_control(pr);
413 result = acpi_processor_get_performance_states(pr);
417 /* We need to call _PPC once when cpufreq starts */
419 result = acpi_processor_get_platform_limit(pr);
424 * Having _PPC but missing frequencies (_PSS, _PCT) is a very good hint that
425 * the BIOS is older than the CPU and does not know its frequencies
429 if (ACPI_SUCCESS(acpi_get_handle(pr->handle, "_PPC", &handle))){
430 if(boot_cpu_has(X86_FEATURE_EST))
431 printk(KERN_WARNING FW_BUG "BIOS needs update for CPU "
432 "frequency support\n");
438 int acpi_processor_notify_smm(struct module *calling_module)
441 static int is_done = 0;
444 if (!(acpi_processor_ppc_status & PPC_REGISTERED))
447 if (!try_module_get(calling_module))
450 /* is_done is set to negative if an error occured,
451 * and to postitive if _no_ error occured, but SMM
452 * was already notified. This avoids double notification
453 * which might lead to unexpected results...
456 module_put(calling_module);
458 } else if (is_done < 0) {
459 module_put(calling_module);
465 /* Can't write pstate_control to smi_command if either value is zero */
466 if ((!acpi_gbl_FADT.smi_command) || (!acpi_gbl_FADT.pstate_control)) {
467 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No SMI port or pstate_control\n"));
468 module_put(calling_module);
472 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
473 "Writing pstate_control [0x%x] to smi_command [0x%x]\n",
474 acpi_gbl_FADT.pstate_control, acpi_gbl_FADT.smi_command));
476 status = acpi_os_write_port(acpi_gbl_FADT.smi_command,
477 (u32) acpi_gbl_FADT.pstate_control, 8);
478 if (ACPI_FAILURE(status)) {
479 ACPI_EXCEPTION((AE_INFO, status,
480 "Failed to write pstate_control [0x%x] to "
481 "smi_command [0x%x]", acpi_gbl_FADT.pstate_control,
482 acpi_gbl_FADT.smi_command));
483 module_put(calling_module);
487 /* Success. If there's no _PPC, we need to fear nothing, so
488 * we can allow the cpufreq driver to be rmmod'ed. */
491 if (!(acpi_processor_ppc_status & PPC_IN_USE))
492 module_put(calling_module);
497 EXPORT_SYMBOL(acpi_processor_notify_smm);
499 static int acpi_processor_get_psd(struct acpi_processor *pr)
502 acpi_status status = AE_OK;
503 struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
504 struct acpi_buffer format = {sizeof("NNNNN"), "NNNNN"};
505 struct acpi_buffer state = {0, NULL};
506 union acpi_object *psd = NULL;
507 struct acpi_psd_package *pdomain;
509 status = acpi_evaluate_object(pr->handle, "_PSD", NULL, &buffer);
510 if (ACPI_FAILURE(status)) {
514 psd = buffer.pointer;
515 if (!psd || (psd->type != ACPI_TYPE_PACKAGE)) {
516 printk(KERN_ERR PREFIX "Invalid _PSD data\n");
521 if (psd->package.count != 1) {
522 printk(KERN_ERR PREFIX "Invalid _PSD data\n");
527 pdomain = &(pr->performance->domain_info);
529 state.length = sizeof(struct acpi_psd_package);
530 state.pointer = pdomain;
532 status = acpi_extract_package(&(psd->package.elements[0]),
534 if (ACPI_FAILURE(status)) {
535 printk(KERN_ERR PREFIX "Invalid _PSD data\n");
540 if (pdomain->num_entries != ACPI_PSD_REV0_ENTRIES) {
541 printk(KERN_ERR PREFIX "Unknown _PSD:num_entries\n");
546 if (pdomain->revision != ACPI_PSD_REV0_REVISION) {
547 printk(KERN_ERR PREFIX "Unknown _PSD:revision\n");
552 if (pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ALL &&
553 pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ANY &&
554 pdomain->coord_type != DOMAIN_COORD_TYPE_HW_ALL) {
555 printk(KERN_ERR PREFIX "Invalid _PSD:coord_type\n");
560 kfree(buffer.pointer);
564 int acpi_processor_preregister_performance(
565 struct acpi_processor_performance __percpu *performance)
567 int count, count_target;
570 cpumask_var_t covered_cpus;
571 struct acpi_processor *pr;
572 struct acpi_psd_package *pdomain;
573 struct acpi_processor *match_pr;
574 struct acpi_psd_package *match_pdomain;
576 if (!zalloc_cpumask_var(&covered_cpus, GFP_KERNEL))
579 mutex_lock(&performance_mutex);
582 * Check if another driver has already registered, and abort before
583 * changing pr->performance if it has. Check input data as well.
585 for_each_possible_cpu(i) {
586 pr = per_cpu(processors, i);
588 /* Look only at processors in ACPI namespace */
592 if (pr->performance) {
597 if (!performance || !per_cpu_ptr(performance, i)) {
603 /* Call _PSD for all CPUs */
604 for_each_possible_cpu(i) {
605 pr = per_cpu(processors, i);
609 pr->performance = per_cpu_ptr(performance, i);
610 cpumask_set_cpu(i, pr->performance->shared_cpu_map);
611 if (acpi_processor_get_psd(pr)) {
620 * Now that we have _PSD data from all CPUs, lets setup P-state
623 for_each_possible_cpu(i) {
624 pr = per_cpu(processors, i);
628 if (cpumask_test_cpu(i, covered_cpus))
631 pdomain = &(pr->performance->domain_info);
632 cpumask_set_cpu(i, pr->performance->shared_cpu_map);
633 cpumask_set_cpu(i, covered_cpus);
634 if (pdomain->num_processors <= 1)
637 /* Validate the Domain info */
638 count_target = pdomain->num_processors;
640 if (pdomain->coord_type == DOMAIN_COORD_TYPE_SW_ALL)
641 pr->performance->shared_type = CPUFREQ_SHARED_TYPE_ALL;
642 else if (pdomain->coord_type == DOMAIN_COORD_TYPE_HW_ALL)
643 pr->performance->shared_type = CPUFREQ_SHARED_TYPE_HW;
644 else if (pdomain->coord_type == DOMAIN_COORD_TYPE_SW_ANY)
645 pr->performance->shared_type = CPUFREQ_SHARED_TYPE_ANY;
647 for_each_possible_cpu(j) {
651 match_pr = per_cpu(processors, j);
655 match_pdomain = &(match_pr->performance->domain_info);
656 if (match_pdomain->domain != pdomain->domain)
659 /* Here i and j are in the same domain */
661 if (match_pdomain->num_processors != count_target) {
666 if (pdomain->coord_type != match_pdomain->coord_type) {
671 cpumask_set_cpu(j, covered_cpus);
672 cpumask_set_cpu(j, pr->performance->shared_cpu_map);
676 for_each_possible_cpu(j) {
680 match_pr = per_cpu(processors, j);
684 match_pdomain = &(match_pr->performance->domain_info);
685 if (match_pdomain->domain != pdomain->domain)
688 match_pr->performance->shared_type =
689 pr->performance->shared_type;
690 cpumask_copy(match_pr->performance->shared_cpu_map,
691 pr->performance->shared_cpu_map);
696 for_each_possible_cpu(i) {
697 pr = per_cpu(processors, i);
698 if (!pr || !pr->performance)
701 /* Assume no coordination on any error parsing domain info */
703 cpumask_clear(pr->performance->shared_cpu_map);
704 cpumask_set_cpu(i, pr->performance->shared_cpu_map);
705 pr->performance->shared_type = CPUFREQ_SHARED_TYPE_ALL;
707 pr->performance = NULL; /* Will be set for real in register */
711 mutex_unlock(&performance_mutex);
712 free_cpumask_var(covered_cpus);
715 EXPORT_SYMBOL(acpi_processor_preregister_performance);
718 acpi_processor_register_performance(struct acpi_processor_performance
719 *performance, unsigned int cpu)
721 struct acpi_processor *pr;
723 if (!(acpi_processor_ppc_status & PPC_REGISTERED))
726 mutex_lock(&performance_mutex);
728 pr = per_cpu(processors, cpu);
730 mutex_unlock(&performance_mutex);
734 if (pr->performance) {
735 mutex_unlock(&performance_mutex);
739 WARN_ON(!performance);
741 pr->performance = performance;
743 if (acpi_processor_get_performance_info(pr)) {
744 pr->performance = NULL;
745 mutex_unlock(&performance_mutex);
749 mutex_unlock(&performance_mutex);
753 EXPORT_SYMBOL(acpi_processor_register_performance);
756 acpi_processor_unregister_performance(struct acpi_processor_performance
757 *performance, unsigned int cpu)
759 struct acpi_processor *pr;
761 mutex_lock(&performance_mutex);
763 pr = per_cpu(processors, cpu);
765 mutex_unlock(&performance_mutex);
770 kfree(pr->performance->states);
771 pr->performance = NULL;
773 mutex_unlock(&performance_mutex);
778 EXPORT_SYMBOL(acpi_processor_unregister_performance);