blob: a9a1a8fe319939029976cb168f66e33d68b8effe [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * processor_perflib.c - ACPI Processor P-States Library ($Revision: 71 $)
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) 2004 Dominik Brodowski <linux@brodo.de>
7 * Copyright (C) 2004 Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
8 * - Added processor hotplug support
9 *
10 *
11 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
12 *
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.
17 *
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.
22 *
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.
26 *
27 */
28
29
30#include <linux/kernel.h>
31#include <linux/module.h>
32#include <linux/init.h>
33#include <linux/cpufreq.h>
34
35#ifdef CONFIG_X86_ACPI_CPUFREQ_PROC_INTF
36#include <linux/proc_fs.h>
37#include <linux/seq_file.h>
38
39#include <asm/uaccess.h>
40#endif
41
42#include <acpi/acpi_bus.h>
43#include <acpi/processor.h>
44
45
46#define ACPI_PROCESSOR_COMPONENT 0x01000000
47#define ACPI_PROCESSOR_CLASS "processor"
48#define ACPI_PROCESSOR_DRIVER_NAME "ACPI Processor Driver"
49#define ACPI_PROCESSOR_FILE_PERFORMANCE "performance"
50#define _COMPONENT ACPI_PROCESSOR_COMPONENT
51ACPI_MODULE_NAME ("acpi_processor")
52
53
54static DECLARE_MUTEX(performance_sem);
55
56/*
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.
61 *
62 * Also, when a new platform limit value is detected, the CPUfreq
63 * policy is adjusted accordingly.
64 */
65
66#define PPC_REGISTERED 1
67#define PPC_IN_USE 2
68
69static int acpi_processor_ppc_status = 0;
70
71static int acpi_processor_ppc_notifier(struct notifier_block *nb,
72 unsigned long event,
73 void *data)
74{
75 struct cpufreq_policy *policy = data;
76 struct acpi_processor *pr;
77 unsigned int ppc = 0;
78
79 down(&performance_sem);
80
81 if (event != CPUFREQ_INCOMPATIBLE)
82 goto out;
83
84 pr = processors[policy->cpu];
85 if (!pr || !pr->performance)
86 goto out;
87
88 ppc = (unsigned int) pr->performance_platform_limit;
89 if (!ppc)
90 goto out;
91
92 if (ppc > pr->performance->state_count)
93 goto out;
94
95 cpufreq_verify_within_limits(policy, 0,
96 pr->performance->states[ppc].core_frequency * 1000);
97
98 out:
99 up(&performance_sem);
100
101 return 0;
102}
103
104
105static struct notifier_block acpi_ppc_notifier_block = {
106 .notifier_call = acpi_processor_ppc_notifier,
107};
108
109
110static int
111acpi_processor_get_platform_limit (
112 struct acpi_processor* pr)
113{
114 acpi_status status = 0;
115 unsigned long ppc = 0;
116
117 ACPI_FUNCTION_TRACE("acpi_processor_get_platform_limit");
118
119 if (!pr)
120 return_VALUE(-EINVAL);
121
122 /*
123 * _PPC indicates the maximum state currently supported by the platform
124 * (e.g. 0 = states 0..n; 1 = states 1..n; etc.
125 */
126 status = acpi_evaluate_integer(pr->handle, "_PPC", NULL, &ppc);
127
128 if (status != AE_NOT_FOUND)
129 acpi_processor_ppc_status |= PPC_IN_USE;
130
131 if(ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
132 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error evaluating _PPC\n"));
133 return_VALUE(-ENODEV);
134 }
135
136 pr->performance_platform_limit = (int) ppc;
137
138 return_VALUE(0);
139}
140
141
142int acpi_processor_ppc_has_changed(
143 struct acpi_processor *pr)
144{
145 int ret = acpi_processor_get_platform_limit(pr);
146 if (ret < 0)
147 return (ret);
148 else
149 return cpufreq_update_policy(pr->id);
150}
151
152
153void acpi_processor_ppc_init(void) {
154 if (!cpufreq_register_notifier(&acpi_ppc_notifier_block, CPUFREQ_POLICY_NOTIFIER))
155 acpi_processor_ppc_status |= PPC_REGISTERED;
156 else
157 printk(KERN_DEBUG "Warning: Processor Platform Limit not supported.\n");
158}
159
160
161void acpi_processor_ppc_exit(void) {
162 if (acpi_processor_ppc_status & PPC_REGISTERED)
163 cpufreq_unregister_notifier(&acpi_ppc_notifier_block, CPUFREQ_POLICY_NOTIFIER);
164
165 acpi_processor_ppc_status &= ~PPC_REGISTERED;
166}
167
168/*
169 * when registering a cpufreq driver with this ACPI processor driver, the
170 * _PCT and _PSS structures are read out and written into struct
171 * acpi_processor_performance.
172 */
173static int acpi_processor_set_pdc (struct acpi_processor *pr)
174{
175 acpi_status status = AE_OK;
176 u32 arg0_buf[3];
177 union acpi_object arg0 = {ACPI_TYPE_BUFFER};
178 struct acpi_object_list no_object = {1, &arg0};
179 struct acpi_object_list *pdc;
180
181 ACPI_FUNCTION_TRACE("acpi_processor_set_pdc");
182
183 arg0.buffer.length = 12;
184 arg0.buffer.pointer = (u8 *) arg0_buf;
185 arg0_buf[0] = ACPI_PDC_REVISION_ID;
186 arg0_buf[1] = 0;
187 arg0_buf[2] = 0;
188
189 pdc = (pr->performance->pdc) ? pr->performance->pdc : &no_object;
190
191 status = acpi_evaluate_object(pr->handle, "_PDC", pdc, NULL);
192
193 if ((ACPI_FAILURE(status)) && (pr->performance->pdc))
194 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Error evaluating _PDC, using legacy perf. control...\n"));
195
196 return_VALUE(status);
197}
198
199
200static int
201acpi_processor_get_performance_control (
202 struct acpi_processor *pr)
203{
204 int result = 0;
205 acpi_status status = 0;
206 struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
207 union acpi_object *pct = NULL;
208 union acpi_object obj = {0};
209
210 ACPI_FUNCTION_TRACE("acpi_processor_get_performance_control");
211
212 status = acpi_evaluate_object(pr->handle, "_PCT", NULL, &buffer);
213 if(ACPI_FAILURE(status)) {
214 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error evaluating _PCT\n"));
215 return_VALUE(-ENODEV);
216 }
217
218 pct = (union acpi_object *) buffer.pointer;
219 if (!pct || (pct->type != ACPI_TYPE_PACKAGE)
220 || (pct->package.count != 2)) {
221 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid _PCT data\n"));
222 result = -EFAULT;
223 goto end;
224 }
225
226 /*
227 * control_register
228 */
229
230 obj = pct->package.elements[0];
231
232 if ((obj.type != ACPI_TYPE_BUFFER)
233 || (obj.buffer.length < sizeof(struct acpi_pct_register))
234 || (obj.buffer.pointer == NULL)) {
235 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
236 "Invalid _PCT data (control_register)\n"));
237 result = -EFAULT;
238 goto end;
239 }
240 memcpy(&pr->performance->control_register, obj.buffer.pointer, sizeof(struct acpi_pct_register));
241
242
243 /*
244 * status_register
245 */
246
247 obj = pct->package.elements[1];
248
249 if ((obj.type != ACPI_TYPE_BUFFER)
250 || (obj.buffer.length < sizeof(struct acpi_pct_register))
251 || (obj.buffer.pointer == NULL)) {
252 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
253 "Invalid _PCT data (status_register)\n"));
254 result = -EFAULT;
255 goto end;
256 }
257
258 memcpy(&pr->performance->status_register, obj.buffer.pointer, sizeof(struct acpi_pct_register));
259
260end:
261 acpi_os_free(buffer.pointer);
262
263 return_VALUE(result);
264}
265
266
267static int
268acpi_processor_get_performance_states (
269 struct acpi_processor *pr)
270{
271 int result = 0;
272 acpi_status status = AE_OK;
273 struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
274 struct acpi_buffer format = {sizeof("NNNNNN"), "NNNNNN"};
275 struct acpi_buffer state = {0, NULL};
276 union acpi_object *pss = NULL;
277 int i;
278
279 ACPI_FUNCTION_TRACE("acpi_processor_get_performance_states");
280
281 status = acpi_evaluate_object(pr->handle, "_PSS", NULL, &buffer);
282 if(ACPI_FAILURE(status)) {
283 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error evaluating _PSS\n"));
284 return_VALUE(-ENODEV);
285 }
286
287 pss = (union acpi_object *) buffer.pointer;
288 if (!pss || (pss->type != ACPI_TYPE_PACKAGE)) {
289 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid _PSS data\n"));
290 result = -EFAULT;
291 goto end;
292 }
293
294 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d performance states\n",
295 pss->package.count));
296
297 pr->performance->state_count = pss->package.count;
298 pr->performance->states = kmalloc(sizeof(struct acpi_processor_px) * pss->package.count, GFP_KERNEL);
299 if (!pr->performance->states) {
300 result = -ENOMEM;
301 goto end;
302 }
303
304 for (i = 0; i < pr->performance->state_count; i++) {
305
306 struct acpi_processor_px *px = &(pr->performance->states[i]);
307
308 state.length = sizeof(struct acpi_processor_px);
309 state.pointer = px;
310
311 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Extracting state %d\n", i));
312
313 status = acpi_extract_package(&(pss->package.elements[i]),
314 &format, &state);
315 if (ACPI_FAILURE(status)) {
316 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid _PSS data\n"));
317 result = -EFAULT;
318 kfree(pr->performance->states);
319 goto end;
320 }
321
322 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
323 "State [%d]: core_frequency[%d] power[%d] transition_latency[%d] bus_master_latency[%d] control[0x%x] status[0x%x]\n",
324 i,
325 (u32) px->core_frequency,
326 (u32) px->power,
327 (u32) px->transition_latency,
328 (u32) px->bus_master_latency,
329 (u32) px->control,
330 (u32) px->status));
331
332 if (!px->core_frequency) {
333 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid _PSS data: freq is zero\n"));
334 result = -EFAULT;
335 kfree(pr->performance->states);
336 goto end;
337 }
338 }
339
340end:
341 acpi_os_free(buffer.pointer);
342
343 return_VALUE(result);
344}
345
346
347static int
348acpi_processor_get_performance_info (
349 struct acpi_processor *pr)
350{
351 int result = 0;
352 acpi_status status = AE_OK;
353 acpi_handle handle = NULL;
354
355 ACPI_FUNCTION_TRACE("acpi_processor_get_performance_info");
356
357 if (!pr || !pr->performance || !pr->handle)
358 return_VALUE(-EINVAL);
359
360 acpi_processor_set_pdc(pr);
361
362 status = acpi_get_handle(pr->handle, "_PCT", &handle);
363 if (ACPI_FAILURE(status)) {
364 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
365 "ACPI-based processor performance control unavailable\n"));
366 return_VALUE(-ENODEV);
367 }
368
369 result = acpi_processor_get_performance_control(pr);
370 if (result)
371 return_VALUE(result);
372
373 result = acpi_processor_get_performance_states(pr);
374 if (result)
375 return_VALUE(result);
376
377 result = acpi_processor_get_platform_limit(pr);
378 if (result)
379 return_VALUE(result);
380
381 return_VALUE(0);
382}
383
384
385int acpi_processor_notify_smm(struct module *calling_module) {
386 acpi_status status;
387 static int is_done = 0;
388
389 ACPI_FUNCTION_TRACE("acpi_processor_notify_smm");
390
391 if (!(acpi_processor_ppc_status & PPC_REGISTERED))
392 return_VALUE(-EBUSY);
393
394 if (!try_module_get(calling_module))
395 return_VALUE(-EINVAL);
396
397 /* is_done is set to negative if an error occured,
398 * and to postitive if _no_ error occured, but SMM
399 * was already notified. This avoids double notification
400 * which might lead to unexpected results...
401 */
402 if (is_done > 0) {
403 module_put(calling_module);
404 return_VALUE(0);
405 }
406 else if (is_done < 0) {
407 module_put(calling_module);
408 return_VALUE(is_done);
409 }
410
411 is_done = -EIO;
412
413 /* Can't write pstate_cnt to smi_cmd if either value is zero */
414 if ((!acpi_fadt.smi_cmd) ||
415 (!acpi_fadt.pstate_cnt)) {
416 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
417 "No SMI port or pstate_cnt\n"));
418 module_put(calling_module);
419 return_VALUE(0);
420 }
421
422 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Writing pstate_cnt [0x%x] to smi_cmd [0x%x]\n", acpi_fadt.pstate_cnt, acpi_fadt.smi_cmd));
423
424 /* FADT v1 doesn't support pstate_cnt, many BIOS vendors use
425 * it anyway, so we need to support it... */
426 if (acpi_fadt_is_v1) {
427 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Using v1.0 FADT reserved value for pstate_cnt\n"));
428 }
429
430 status = acpi_os_write_port (acpi_fadt.smi_cmd,
431 (u32) acpi_fadt.pstate_cnt, 8);
432 if (ACPI_FAILURE (status)) {
433 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
434 "Failed to write pstate_cnt [0x%x] to "
435 "smi_cmd [0x%x]\n", acpi_fadt.pstate_cnt, acpi_fadt.smi_cmd));
436 module_put(calling_module);
437 return_VALUE(status);
438 }
439
440 /* Success. If there's no _PPC, we need to fear nothing, so
441 * we can allow the cpufreq driver to be rmmod'ed. */
442 is_done = 1;
443
444 if (!(acpi_processor_ppc_status & PPC_IN_USE))
445 module_put(calling_module);
446
447 return_VALUE(0);
448}
449EXPORT_SYMBOL(acpi_processor_notify_smm);
450
451
452#ifdef CONFIG_X86_ACPI_CPUFREQ_PROC_INTF
453/* /proc/acpi/processor/../performance interface (DEPRECATED) */
454
455static int acpi_processor_perf_open_fs(struct inode *inode, struct file *file);
456static struct file_operations acpi_processor_perf_fops = {
457 .open = acpi_processor_perf_open_fs,
458 .read = seq_read,
459 .llseek = seq_lseek,
460 .release = single_release,
461};
462
463static int acpi_processor_perf_seq_show(struct seq_file *seq, void *offset)
464{
465 struct acpi_processor *pr = (struct acpi_processor *)seq->private;
466 int i;
467
468 ACPI_FUNCTION_TRACE("acpi_processor_perf_seq_show");
469
470 if (!pr)
471 goto end;
472
473 if (!pr->performance) {
474 seq_puts(seq, "<not supported>\n");
475 goto end;
476 }
477
478 seq_printf(seq, "state count: %d\n"
479 "active state: P%d\n",
480 pr->performance->state_count,
481 pr->performance->state);
482
483 seq_puts(seq, "states:\n");
484 for (i = 0; i < pr->performance->state_count; i++)
485 seq_printf(seq, " %cP%d: %d MHz, %d mW, %d uS\n",
486 (i == pr->performance->state?'*':' '), i,
487 (u32) pr->performance->states[i].core_frequency,
488 (u32) pr->performance->states[i].power,
489 (u32) pr->performance->states[i].transition_latency);
490
491end:
492 return_VALUE(0);
493}
494
495static int acpi_processor_perf_open_fs(struct inode *inode, struct file *file)
496{
497 return single_open(file, acpi_processor_perf_seq_show,
498 PDE(inode)->data);
499}
500
501static ssize_t
502acpi_processor_write_performance (
503 struct file *file,
504 const char __user *buffer,
505 size_t count,
506 loff_t *data)
507{
508 int result = 0;
509 struct seq_file *m = (struct seq_file *) file->private_data;
510 struct acpi_processor *pr = (struct acpi_processor *) m->private;
511 struct acpi_processor_performance *perf;
512 char state_string[12] = {'\0'};
513 unsigned int new_state = 0;
514 struct cpufreq_policy policy;
515
516 ACPI_FUNCTION_TRACE("acpi_processor_write_performance");
517
518 if (!pr || (count > sizeof(state_string) - 1))
519 return_VALUE(-EINVAL);
520
521 perf = pr->performance;
522 if (!perf)
523 return_VALUE(-EINVAL);
524
525 if (copy_from_user(state_string, buffer, count))
526 return_VALUE(-EFAULT);
527
528 state_string[count] = '\0';
529 new_state = simple_strtoul(state_string, NULL, 0);
530
531 if (new_state >= perf->state_count)
532 return_VALUE(-EINVAL);
533
534 cpufreq_get_policy(&policy, pr->id);
535
536 policy.cpu = pr->id;
537 policy.min = perf->states[new_state].core_frequency * 1000;
538 policy.max = perf->states[new_state].core_frequency * 1000;
539
540 result = cpufreq_set_policy(&policy);
541 if (result)
542 return_VALUE(result);
543
544 return_VALUE(count);
545}
546
547static void
548acpi_cpufreq_add_file (
549 struct acpi_processor *pr)
550{
551 struct proc_dir_entry *entry = NULL;
552 struct acpi_device *device = NULL;
553
554 ACPI_FUNCTION_TRACE("acpi_cpufreq_addfile");
555
556 if (acpi_bus_get_device(pr->handle, &device))
557 return_VOID;
558
559 /* add file 'performance' [R/W] */
560 entry = create_proc_entry(ACPI_PROCESSOR_FILE_PERFORMANCE,
561 S_IFREG|S_IRUGO|S_IWUSR, acpi_device_dir(device));
562 if (!entry)
563 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
564 "Unable to create '%s' fs entry\n",
565 ACPI_PROCESSOR_FILE_PERFORMANCE));
566 else {
567 entry->proc_fops = &acpi_processor_perf_fops;
568 entry->proc_fops->write = acpi_processor_write_performance;
569 entry->data = acpi_driver_data(device);
570 entry->owner = THIS_MODULE;
571 }
572 return_VOID;
573}
574
575static void
576acpi_cpufreq_remove_file (
577 struct acpi_processor *pr)
578{
579 struct acpi_device *device = NULL;
580
581 ACPI_FUNCTION_TRACE("acpi_cpufreq_addfile");
582
583 if (acpi_bus_get_device(pr->handle, &device))
584 return_VOID;
585
586 /* remove file 'performance' */
587 remove_proc_entry(ACPI_PROCESSOR_FILE_PERFORMANCE,
588 acpi_device_dir(device));
589
590 return_VOID;
591}
592
593#else
594static void acpi_cpufreq_add_file (struct acpi_processor *pr) { return; }
595static void acpi_cpufreq_remove_file (struct acpi_processor *pr) { return; }
596#endif /* CONFIG_X86_ACPI_CPUFREQ_PROC_INTF */
597
598
599int
600acpi_processor_register_performance (
601 struct acpi_processor_performance * performance,
602 unsigned int cpu)
603{
604 struct acpi_processor *pr;
605
606 ACPI_FUNCTION_TRACE("acpi_processor_register_performance");
607
608 if (!(acpi_processor_ppc_status & PPC_REGISTERED))
609 return_VALUE(-EINVAL);
610
611 down(&performance_sem);
612
613 pr = processors[cpu];
614 if (!pr) {
615 up(&performance_sem);
616 return_VALUE(-ENODEV);
617 }
618
619 if (pr->performance) {
620 up(&performance_sem);
621 return_VALUE(-EBUSY);
622 }
623
624 pr->performance = performance;
625
626 if (acpi_processor_get_performance_info(pr)) {
627 pr->performance = NULL;
628 up(&performance_sem);
629 return_VALUE(-EIO);
630 }
631
632 acpi_cpufreq_add_file(pr);
633
634 up(&performance_sem);
635 return_VALUE(0);
636}
637EXPORT_SYMBOL(acpi_processor_register_performance);
638
639
640void
641acpi_processor_unregister_performance (
642 struct acpi_processor_performance * performance,
643 unsigned int cpu)
644{
645 struct acpi_processor *pr;
646
647 ACPI_FUNCTION_TRACE("acpi_processor_unregister_performance");
648
649 down(&performance_sem);
650
651 pr = processors[cpu];
652 if (!pr) {
653 up(&performance_sem);
654 return_VOID;
655 }
656
657 kfree(pr->performance->states);
658 pr->performance = NULL;
659
660 acpi_cpufreq_remove_file(pr);
661
662 up(&performance_sem);
663
664 return_VOID;
665}
666EXPORT_SYMBOL(acpi_processor_unregister_performance);