Linux 2.6.26-rc5
[linux-2.6/openmoko-kernel/knife-kernel.git] / drivers / acpi / processor_perflib.c
blobd80b2d1441afbadb561cf58abfdb135dd20aeb8e
1 /*
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>
34 #ifdef CONFIG_X86_ACPI_CPUFREQ_PROC_INTF
35 #include <linux/proc_fs.h>
36 #include <linux/seq_file.h>
37 #include <linux/mutex.h>
39 #include <asm/uaccess.h>
40 #endif
42 #include <acpi/acpi_bus.h>
43 #include <acpi/processor.h>
45 #define ACPI_PROCESSOR_COMPONENT 0x01000000
46 #define ACPI_PROCESSOR_CLASS "processor"
47 #define ACPI_PROCESSOR_FILE_PERFORMANCE "performance"
48 #define _COMPONENT ACPI_PROCESSOR_COMPONENT
49 ACPI_MODULE_NAME("processor_perflib");
51 static DEFINE_MUTEX(performance_mutex);
53 /* Use cpufreq debug layer for _PPC changes. */
54 #define cpufreq_printk(msg...) cpufreq_debug_printk(CPUFREQ_DEBUG_CORE, \
55 "cpufreq-core", msg)
58 * _PPC support is implemented as a CPUfreq policy notifier:
59 * This means each time a CPUfreq driver registered also with
60 * the ACPI core is asked to change the speed policy, the maximum
61 * value is adjusted so that it is within the platform limit.
63 * Also, when a new platform limit value is detected, the CPUfreq
64 * policy is adjusted accordingly.
67 static unsigned int ignore_ppc = 0;
68 module_param(ignore_ppc, uint, 0644);
69 MODULE_PARM_DESC(ignore_ppc, "If the frequency of your machine gets wrongly" \
70 "limited by BIOS, this should help");
72 #define PPC_REGISTERED 1
73 #define PPC_IN_USE 2
75 static int acpi_processor_ppc_status = 0;
77 static int acpi_processor_ppc_notifier(struct notifier_block *nb,
78 unsigned long event, void *data)
80 struct cpufreq_policy *policy = data;
81 struct acpi_processor *pr;
82 unsigned int ppc = 0;
84 if (ignore_ppc)
85 return 0;
87 mutex_lock(&performance_mutex);
89 if (event != CPUFREQ_INCOMPATIBLE)
90 goto out;
92 pr = processors[policy->cpu];
93 if (!pr || !pr->performance)
94 goto out;
96 ppc = (unsigned int)pr->performance_platform_limit;
98 if (ppc >= pr->performance->state_count)
99 goto out;
101 cpufreq_verify_within_limits(policy, 0,
102 pr->performance->states[ppc].
103 core_frequency * 1000);
105 out:
106 mutex_unlock(&performance_mutex);
108 return 0;
111 static struct notifier_block acpi_ppc_notifier_block = {
112 .notifier_call = acpi_processor_ppc_notifier,
115 static int acpi_processor_get_platform_limit(struct acpi_processor *pr)
117 acpi_status status = 0;
118 unsigned long ppc = 0;
121 if (!pr)
122 return -EINVAL;
125 * _PPC indicates the maximum state currently supported by the platform
126 * (e.g. 0 = states 0..n; 1 = states 1..n; etc.
128 status = acpi_evaluate_integer(pr->handle, "_PPC", NULL, &ppc);
130 if (status != AE_NOT_FOUND)
131 acpi_processor_ppc_status |= PPC_IN_USE;
133 if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
134 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PPC"));
135 return -ENODEV;
138 cpufreq_printk("CPU %d: _PPC is %d - frequency %s limited\n", pr->id,
139 (int)ppc, ppc ? "" : "not");
141 pr->performance_platform_limit = (int)ppc;
143 return 0;
146 int acpi_processor_ppc_has_changed(struct acpi_processor *pr)
148 int ret;
150 if (ignore_ppc)
151 return 0;
153 ret = acpi_processor_get_platform_limit(pr);
155 if (ret < 0)
156 return (ret);
157 else
158 return cpufreq_update_policy(pr->id);
161 void acpi_processor_ppc_init(void)
163 if (!cpufreq_register_notifier
164 (&acpi_ppc_notifier_block, CPUFREQ_POLICY_NOTIFIER))
165 acpi_processor_ppc_status |= PPC_REGISTERED;
166 else
167 printk(KERN_DEBUG
168 "Warning: Processor Platform Limit not supported.\n");
171 void acpi_processor_ppc_exit(void)
173 if (acpi_processor_ppc_status & PPC_REGISTERED)
174 cpufreq_unregister_notifier(&acpi_ppc_notifier_block,
175 CPUFREQ_POLICY_NOTIFIER);
177 acpi_processor_ppc_status &= ~PPC_REGISTERED;
180 static int acpi_processor_get_performance_control(struct acpi_processor *pr)
182 int result = 0;
183 acpi_status status = 0;
184 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
185 union acpi_object *pct = NULL;
186 union acpi_object obj = { 0 };
189 status = acpi_evaluate_object(pr->handle, "_PCT", NULL, &buffer);
190 if (ACPI_FAILURE(status)) {
191 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PCT"));
192 return -ENODEV;
195 pct = (union acpi_object *)buffer.pointer;
196 if (!pct || (pct->type != ACPI_TYPE_PACKAGE)
197 || (pct->package.count != 2)) {
198 printk(KERN_ERR PREFIX "Invalid _PCT data\n");
199 result = -EFAULT;
200 goto end;
204 * control_register
207 obj = pct->package.elements[0];
209 if ((obj.type != ACPI_TYPE_BUFFER)
210 || (obj.buffer.length < sizeof(struct acpi_pct_register))
211 || (obj.buffer.pointer == NULL)) {
212 printk(KERN_ERR PREFIX "Invalid _PCT data (control_register)\n");
213 result = -EFAULT;
214 goto end;
216 memcpy(&pr->performance->control_register, obj.buffer.pointer,
217 sizeof(struct acpi_pct_register));
220 * status_register
223 obj = pct->package.elements[1];
225 if ((obj.type != ACPI_TYPE_BUFFER)
226 || (obj.buffer.length < sizeof(struct acpi_pct_register))
227 || (obj.buffer.pointer == NULL)) {
228 printk(KERN_ERR PREFIX "Invalid _PCT data (status_register)\n");
229 result = -EFAULT;
230 goto end;
233 memcpy(&pr->performance->status_register, obj.buffer.pointer,
234 sizeof(struct acpi_pct_register));
236 end:
237 kfree(buffer.pointer);
239 return result;
242 static int acpi_processor_get_performance_states(struct acpi_processor *pr)
244 int result = 0;
245 acpi_status status = AE_OK;
246 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
247 struct acpi_buffer format = { sizeof("NNNNNN"), "NNNNNN" };
248 struct acpi_buffer state = { 0, NULL };
249 union acpi_object *pss = NULL;
250 int i;
253 status = acpi_evaluate_object(pr->handle, "_PSS", NULL, &buffer);
254 if (ACPI_FAILURE(status)) {
255 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PSS"));
256 return -ENODEV;
259 pss = buffer.pointer;
260 if (!pss || (pss->type != ACPI_TYPE_PACKAGE)) {
261 printk(KERN_ERR PREFIX "Invalid _PSS data\n");
262 result = -EFAULT;
263 goto end;
266 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d performance states\n",
267 pss->package.count));
269 pr->performance->state_count = pss->package.count;
270 pr->performance->states =
271 kmalloc(sizeof(struct acpi_processor_px) * pss->package.count,
272 GFP_KERNEL);
273 if (!pr->performance->states) {
274 result = -ENOMEM;
275 goto end;
278 for (i = 0; i < pr->performance->state_count; i++) {
280 struct acpi_processor_px *px = &(pr->performance->states[i]);
282 state.length = sizeof(struct acpi_processor_px);
283 state.pointer = px;
285 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Extracting state %d\n", i));
287 status = acpi_extract_package(&(pss->package.elements[i]),
288 &format, &state);
289 if (ACPI_FAILURE(status)) {
290 ACPI_EXCEPTION((AE_INFO, status, "Invalid _PSS data"));
291 result = -EFAULT;
292 kfree(pr->performance->states);
293 goto end;
296 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
297 "State [%d]: core_frequency[%d] power[%d] transition_latency[%d] bus_master_latency[%d] control[0x%x] status[0x%x]\n",
299 (u32) px->core_frequency,
300 (u32) px->power,
301 (u32) px->transition_latency,
302 (u32) px->bus_master_latency,
303 (u32) px->control, (u32) px->status));
305 if (!px->core_frequency) {
306 printk(KERN_ERR PREFIX
307 "Invalid _PSS data: freq is zero\n");
308 result = -EFAULT;
309 kfree(pr->performance->states);
310 goto end;
314 end:
315 kfree(buffer.pointer);
317 return result;
320 static int acpi_processor_get_performance_info(struct acpi_processor *pr)
322 int result = 0;
323 acpi_status status = AE_OK;
324 acpi_handle handle = NULL;
327 if (!pr || !pr->performance || !pr->handle)
328 return -EINVAL;
330 status = acpi_get_handle(pr->handle, "_PCT", &handle);
331 if (ACPI_FAILURE(status)) {
332 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
333 "ACPI-based processor performance control unavailable\n"));
334 return -ENODEV;
337 result = acpi_processor_get_performance_control(pr);
338 if (result)
339 return result;
341 result = acpi_processor_get_performance_states(pr);
342 if (result)
343 return result;
345 return 0;
348 int acpi_processor_notify_smm(struct module *calling_module)
350 acpi_status status;
351 static int is_done = 0;
354 if (!(acpi_processor_ppc_status & PPC_REGISTERED))
355 return -EBUSY;
357 if (!try_module_get(calling_module))
358 return -EINVAL;
360 /* is_done is set to negative if an error occured,
361 * and to postitive if _no_ error occured, but SMM
362 * was already notified. This avoids double notification
363 * which might lead to unexpected results...
365 if (is_done > 0) {
366 module_put(calling_module);
367 return 0;
368 } else if (is_done < 0) {
369 module_put(calling_module);
370 return is_done;
373 is_done = -EIO;
375 /* Can't write pstate_control to smi_command if either value is zero */
376 if ((!acpi_gbl_FADT.smi_command) || (!acpi_gbl_FADT.pstate_control)) {
377 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No SMI port or pstate_control\n"));
378 module_put(calling_module);
379 return 0;
382 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
383 "Writing pstate_control [0x%x] to smi_command [0x%x]\n",
384 acpi_gbl_FADT.pstate_control, acpi_gbl_FADT.smi_command));
386 status = acpi_os_write_port(acpi_gbl_FADT.smi_command,
387 (u32) acpi_gbl_FADT.pstate_control, 8);
388 if (ACPI_FAILURE(status)) {
389 ACPI_EXCEPTION((AE_INFO, status,
390 "Failed to write pstate_control [0x%x] to "
391 "smi_command [0x%x]", acpi_gbl_FADT.pstate_control,
392 acpi_gbl_FADT.smi_command));
393 module_put(calling_module);
394 return status;
397 /* Success. If there's no _PPC, we need to fear nothing, so
398 * we can allow the cpufreq driver to be rmmod'ed. */
399 is_done = 1;
401 if (!(acpi_processor_ppc_status & PPC_IN_USE))
402 module_put(calling_module);
404 return 0;
407 EXPORT_SYMBOL(acpi_processor_notify_smm);
409 #ifdef CONFIG_X86_ACPI_CPUFREQ_PROC_INTF
410 /* /proc/acpi/processor/../performance interface (DEPRECATED) */
412 static int acpi_processor_perf_open_fs(struct inode *inode, struct file *file);
413 static struct file_operations acpi_processor_perf_fops = {
414 .owner = THIS_MODULE,
415 .open = acpi_processor_perf_open_fs,
416 .read = seq_read,
417 .llseek = seq_lseek,
418 .release = single_release,
421 static int acpi_processor_perf_seq_show(struct seq_file *seq, void *offset)
423 struct acpi_processor *pr = seq->private;
424 int i;
427 if (!pr)
428 goto end;
430 if (!pr->performance) {
431 seq_puts(seq, "<not supported>\n");
432 goto end;
435 seq_printf(seq, "state count: %d\n"
436 "active state: P%d\n",
437 pr->performance->state_count, pr->performance->state);
439 seq_puts(seq, "states:\n");
440 for (i = 0; i < pr->performance->state_count; i++)
441 seq_printf(seq,
442 " %cP%d: %d MHz, %d mW, %d uS\n",
443 (i == pr->performance->state ? '*' : ' '), i,
444 (u32) pr->performance->states[i].core_frequency,
445 (u32) pr->performance->states[i].power,
446 (u32) pr->performance->states[i].transition_latency);
448 end:
449 return 0;
452 static int acpi_processor_perf_open_fs(struct inode *inode, struct file *file)
454 return single_open(file, acpi_processor_perf_seq_show,
455 PDE(inode)->data);
458 static void acpi_cpufreq_add_file(struct acpi_processor *pr)
460 struct acpi_device *device = NULL;
463 if (acpi_bus_get_device(pr->handle, &device))
464 return;
466 /* add file 'performance' [R/W] */
467 proc_create_data(ACPI_PROCESSOR_FILE_PERFORMANCE, S_IFREG | S_IRUGO,
468 acpi_device_dir(device),
469 &acpi_processor_perf_fops, acpi_driver_data(device));
470 return;
473 static void acpi_cpufreq_remove_file(struct acpi_processor *pr)
475 struct acpi_device *device = NULL;
478 if (acpi_bus_get_device(pr->handle, &device))
479 return;
481 /* remove file 'performance' */
482 remove_proc_entry(ACPI_PROCESSOR_FILE_PERFORMANCE,
483 acpi_device_dir(device));
485 return;
488 #else
489 static void acpi_cpufreq_add_file(struct acpi_processor *pr)
491 return;
493 static void acpi_cpufreq_remove_file(struct acpi_processor *pr)
495 return;
497 #endif /* CONFIG_X86_ACPI_CPUFREQ_PROC_INTF */
499 static int acpi_processor_get_psd(struct acpi_processor *pr)
501 int result = 0;
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)) {
511 return -ENODEV;
514 psd = buffer.pointer;
515 if (!psd || (psd->type != ACPI_TYPE_PACKAGE)) {
516 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid _PSD data\n"));
517 result = -EFAULT;
518 goto end;
521 if (psd->package.count != 1) {
522 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid _PSD data\n"));
523 result = -EFAULT;
524 goto end;
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]),
533 &format, &state);
534 if (ACPI_FAILURE(status)) {
535 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid _PSD data\n"));
536 result = -EFAULT;
537 goto end;
540 if (pdomain->num_entries != ACPI_PSD_REV0_ENTRIES) {
541 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Unknown _PSD:num_entries\n"));
542 result = -EFAULT;
543 goto end;
546 if (pdomain->revision != ACPI_PSD_REV0_REVISION) {
547 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Unknown _PSD:revision\n"));
548 result = -EFAULT;
549 goto end;
552 end:
553 kfree(buffer.pointer);
554 return result;
557 int acpi_processor_preregister_performance(
558 struct acpi_processor_performance *performance)
560 int count, count_target;
561 int retval = 0;
562 unsigned int i, j;
563 cpumask_t covered_cpus;
564 struct acpi_processor *pr;
565 struct acpi_psd_package *pdomain;
566 struct acpi_processor *match_pr;
567 struct acpi_psd_package *match_pdomain;
569 mutex_lock(&performance_mutex);
571 retval = 0;
573 /* Call _PSD for all CPUs */
574 for_each_possible_cpu(i) {
575 pr = processors[i];
576 if (!pr) {
577 /* Look only at processors in ACPI namespace */
578 continue;
581 if (pr->performance) {
582 retval = -EBUSY;
583 continue;
586 if (!performance || !percpu_ptr(performance, i)) {
587 retval = -EINVAL;
588 continue;
591 pr->performance = percpu_ptr(performance, i);
592 cpu_set(i, pr->performance->shared_cpu_map);
593 if (acpi_processor_get_psd(pr)) {
594 retval = -EINVAL;
595 continue;
598 if (retval)
599 goto err_ret;
602 * Now that we have _PSD data from all CPUs, lets setup P-state
603 * domain info.
605 for_each_possible_cpu(i) {
606 pr = processors[i];
607 if (!pr)
608 continue;
610 /* Basic validity check for domain info */
611 pdomain = &(pr->performance->domain_info);
612 if ((pdomain->revision != ACPI_PSD_REV0_REVISION) ||
613 (pdomain->num_entries != ACPI_PSD_REV0_ENTRIES)) {
614 retval = -EINVAL;
615 goto err_ret;
617 if (pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ALL &&
618 pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ANY &&
619 pdomain->coord_type != DOMAIN_COORD_TYPE_HW_ALL) {
620 retval = -EINVAL;
621 goto err_ret;
625 cpus_clear(covered_cpus);
626 for_each_possible_cpu(i) {
627 pr = processors[i];
628 if (!pr)
629 continue;
631 if (cpu_isset(i, covered_cpus))
632 continue;
634 pdomain = &(pr->performance->domain_info);
635 cpu_set(i, pr->performance->shared_cpu_map);
636 cpu_set(i, covered_cpus);
637 if (pdomain->num_processors <= 1)
638 continue;
640 /* Validate the Domain info */
641 count_target = pdomain->num_processors;
642 count = 1;
643 if (pdomain->coord_type == DOMAIN_COORD_TYPE_SW_ALL)
644 pr->performance->shared_type = CPUFREQ_SHARED_TYPE_ALL;
645 else if (pdomain->coord_type == DOMAIN_COORD_TYPE_HW_ALL)
646 pr->performance->shared_type = CPUFREQ_SHARED_TYPE_HW;
647 else if (pdomain->coord_type == DOMAIN_COORD_TYPE_SW_ANY)
648 pr->performance->shared_type = CPUFREQ_SHARED_TYPE_ANY;
650 for_each_possible_cpu(j) {
651 if (i == j)
652 continue;
654 match_pr = processors[j];
655 if (!match_pr)
656 continue;
658 match_pdomain = &(match_pr->performance->domain_info);
659 if (match_pdomain->domain != pdomain->domain)
660 continue;
662 /* Here i and j are in the same domain */
664 if (match_pdomain->num_processors != count_target) {
665 retval = -EINVAL;
666 goto err_ret;
669 if (pdomain->coord_type != match_pdomain->coord_type) {
670 retval = -EINVAL;
671 goto err_ret;
674 cpu_set(j, covered_cpus);
675 cpu_set(j, pr->performance->shared_cpu_map);
676 count++;
679 for_each_possible_cpu(j) {
680 if (i == j)
681 continue;
683 match_pr = processors[j];
684 if (!match_pr)
685 continue;
687 match_pdomain = &(match_pr->performance->domain_info);
688 if (match_pdomain->domain != pdomain->domain)
689 continue;
691 match_pr->performance->shared_type =
692 pr->performance->shared_type;
693 match_pr->performance->shared_cpu_map =
694 pr->performance->shared_cpu_map;
698 err_ret:
699 for_each_possible_cpu(i) {
700 pr = processors[i];
701 if (!pr || !pr->performance)
702 continue;
704 /* Assume no coordination on any error parsing domain info */
705 if (retval) {
706 cpus_clear(pr->performance->shared_cpu_map);
707 cpu_set(i, pr->performance->shared_cpu_map);
708 pr->performance->shared_type = CPUFREQ_SHARED_TYPE_ALL;
710 pr->performance = NULL; /* Will be set for real in register */
713 mutex_unlock(&performance_mutex);
714 return retval;
716 EXPORT_SYMBOL(acpi_processor_preregister_performance);
720 acpi_processor_register_performance(struct acpi_processor_performance
721 *performance, unsigned int cpu)
723 struct acpi_processor *pr;
726 if (!(acpi_processor_ppc_status & PPC_REGISTERED))
727 return -EINVAL;
729 mutex_lock(&performance_mutex);
731 pr = processors[cpu];
732 if (!pr) {
733 mutex_unlock(&performance_mutex);
734 return -ENODEV;
737 if (pr->performance) {
738 mutex_unlock(&performance_mutex);
739 return -EBUSY;
742 WARN_ON(!performance);
744 pr->performance = performance;
746 if (acpi_processor_get_performance_info(pr)) {
747 pr->performance = NULL;
748 mutex_unlock(&performance_mutex);
749 return -EIO;
752 acpi_cpufreq_add_file(pr);
754 mutex_unlock(&performance_mutex);
755 return 0;
758 EXPORT_SYMBOL(acpi_processor_register_performance);
760 void
761 acpi_processor_unregister_performance(struct acpi_processor_performance
762 *performance, unsigned int cpu)
764 struct acpi_processor *pr;
767 mutex_lock(&performance_mutex);
769 pr = processors[cpu];
770 if (!pr) {
771 mutex_unlock(&performance_mutex);
772 return;
775 if (pr->performance)
776 kfree(pr->performance->states);
777 pr->performance = NULL;
779 acpi_cpufreq_remove_file(pr);
781 mutex_unlock(&performance_mutex);
783 return;
786 EXPORT_SYMBOL(acpi_processor_unregister_performance);