Remove obsolete #include <linux/config.h>
[linux-2.6.git] / arch / i386 / kernel / cpu / cpufreq / acpi-cpufreq.c
1 /*
2  * acpi-cpufreq.c - ACPI Processor P-States Driver ($Revision: 1.3 $)
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  *
8  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
9  *
10  *  This program is free software; you can redistribute it and/or modify
11  *  it under the terms of the GNU General Public License as published by
12  *  the Free Software Foundation; either version 2 of the License, or (at
13  *  your option) any later version.
14  *
15  *  This program is distributed in the hope that it will be useful, but
16  *  WITHOUT ANY WARRANTY; without even the implied warranty of
17  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
18  *  General Public License for more details.
19  *
20  *  You should have received a copy of the GNU General Public License along
21  *  with this program; if not, write to the Free Software Foundation, Inc.,
22  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
23  *
24  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
25  */
26
27 #include <linux/kernel.h>
28 #include <linux/module.h>
29 #include <linux/init.h>
30 #include <linux/cpufreq.h>
31 #include <linux/proc_fs.h>
32 #include <linux/seq_file.h>
33 #include <linux/compiler.h>
34 #include <linux/sched.h>        /* current */
35 #include <asm/io.h>
36 #include <asm/delay.h>
37 #include <asm/uaccess.h>
38
39 #include <linux/acpi.h>
40 #include <acpi/processor.h>
41
42 #define dprintk(msg...) cpufreq_debug_printk(CPUFREQ_DEBUG_DRIVER, "acpi-cpufreq", msg)
43
44 MODULE_AUTHOR("Paul Diefenbaugh, Dominik Brodowski");
45 MODULE_DESCRIPTION("ACPI Processor P-States Driver");
46 MODULE_LICENSE("GPL");
47
48
49 struct cpufreq_acpi_io {
50         struct acpi_processor_performance       *acpi_data;
51         struct cpufreq_frequency_table          *freq_table;
52         unsigned int                            resume;
53 };
54
55 static struct cpufreq_acpi_io   *acpi_io_data[NR_CPUS];
56 static struct acpi_processor_performance        *acpi_perf_data[NR_CPUS];
57
58 static struct cpufreq_driver acpi_cpufreq_driver;
59
60 static unsigned int acpi_pstate_strict;
61
62 static int
63 acpi_processor_write_port(
64         u16     port,
65         u8      bit_width,
66         u32     value)
67 {
68         if (bit_width <= 8) {
69                 outb(value, port);
70         } else if (bit_width <= 16) {
71                 outw(value, port);
72         } else if (bit_width <= 32) {
73                 outl(value, port);
74         } else {
75                 return -ENODEV;
76         }
77         return 0;
78 }
79
80 static int
81 acpi_processor_read_port(
82         u16     port,
83         u8      bit_width,
84         u32     *ret)
85 {
86         *ret = 0;
87         if (bit_width <= 8) {
88                 *ret = inb(port);
89         } else if (bit_width <= 16) {
90                 *ret = inw(port);
91         } else if (bit_width <= 32) {
92                 *ret = inl(port);
93         } else {
94                 return -ENODEV;
95         }
96         return 0;
97 }
98
99 static int
100 acpi_processor_set_performance (
101         struct cpufreq_acpi_io  *data,
102         unsigned int            cpu,
103         int                     state)
104 {
105         u16                     port = 0;
106         u8                      bit_width = 0;
107         int                     i = 0;
108         int                     ret = 0;
109         u32                     value = 0;
110         int                     retval;
111         struct acpi_processor_performance       *perf;
112
113         dprintk("acpi_processor_set_performance\n");
114
115         retval = 0;
116         perf = data->acpi_data; 
117         if (state == perf->state) {
118                 if (unlikely(data->resume)) {
119                         dprintk("Called after resume, resetting to P%d\n", state);
120                         data->resume = 0;
121                 } else {
122                         dprintk("Already at target state (P%d)\n", state);
123                         return (retval);
124                 }
125         }
126
127         dprintk("Transitioning from P%d to P%d\n", perf->state, state);
128
129         /*
130          * First we write the target state's 'control' value to the
131          * control_register.
132          */
133
134         port = perf->control_register.address;
135         bit_width = perf->control_register.bit_width;
136         value = (u32) perf->states[state].control;
137
138         dprintk("Writing 0x%08x to port 0x%04x\n", value, port);
139
140         ret = acpi_processor_write_port(port, bit_width, value);
141         if (ret) {
142                 dprintk("Invalid port width 0x%04x\n", bit_width);
143                 return (ret);
144         }
145
146         /*
147          * Assume the write went through when acpi_pstate_strict is not used.
148          * As read status_register is an expensive operation and there 
149          * are no specific error cases where an IO port write will fail.
150          */
151         if (acpi_pstate_strict) {
152                 /* Then we read the 'status_register' and compare the value 
153                  * with the target state's 'status' to make sure the 
154                  * transition was successful.
155                  * Note that we'll poll for up to 1ms (100 cycles of 10us) 
156                  * before giving up.
157                  */
158
159                 port = perf->status_register.address;
160                 bit_width = perf->status_register.bit_width;
161
162                 dprintk("Looking for 0x%08x from port 0x%04x\n",
163                         (u32) perf->states[state].status, port);
164
165                 for (i = 0; i < 100; i++) {
166                         ret = acpi_processor_read_port(port, bit_width, &value);
167                         if (ret) {      
168                                 dprintk("Invalid port width 0x%04x\n", bit_width);
169                                 return (ret);
170                         }
171                         if (value == (u32) perf->states[state].status)
172                                 break;
173                         udelay(10);
174                 }
175         } else {
176                 value = (u32) perf->states[state].status;
177         }
178
179         if (unlikely(value != (u32) perf->states[state].status)) {
180                 printk(KERN_WARNING "acpi-cpufreq: Transition failed\n");
181                 retval = -ENODEV;
182                 return (retval);
183         }
184
185         dprintk("Transition successful after %d microseconds\n", i * 10);
186
187         perf->state = state;
188         return (retval);
189 }
190
191
192 static int
193 acpi_cpufreq_target (
194         struct cpufreq_policy   *policy,
195         unsigned int target_freq,
196         unsigned int relation)
197 {
198         struct cpufreq_acpi_io *data = acpi_io_data[policy->cpu];
199         struct acpi_processor_performance *perf;
200         struct cpufreq_freqs freqs;
201         cpumask_t online_policy_cpus;
202         cpumask_t saved_mask;
203         cpumask_t set_mask;
204         cpumask_t covered_cpus;
205         unsigned int cur_state = 0;
206         unsigned int next_state = 0;
207         unsigned int result = 0;
208         unsigned int j;
209         unsigned int tmp;
210
211         dprintk("acpi_cpufreq_setpolicy\n");
212
213         result = cpufreq_frequency_table_target(policy,
214                         data->freq_table,
215                         target_freq,
216                         relation,
217                         &next_state);
218         if (unlikely(result))
219                 return (result);
220
221         perf = data->acpi_data;
222         cur_state = perf->state;
223         freqs.old = data->freq_table[cur_state].frequency;
224         freqs.new = data->freq_table[next_state].frequency;
225
226 #ifdef CONFIG_HOTPLUG_CPU
227         /* cpufreq holds the hotplug lock, so we are safe from here on */
228         cpus_and(online_policy_cpus, cpu_online_map, policy->cpus);
229 #else
230         online_policy_cpus = policy->cpus;
231 #endif
232
233         for_each_cpu_mask(j, online_policy_cpus) {
234                 freqs.cpu = j;
235                 cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
236         }
237
238         /*
239          * We need to call driver->target() on all or any CPU in
240          * policy->cpus, depending on policy->shared_type.
241          */
242         saved_mask = current->cpus_allowed;
243         cpus_clear(covered_cpus);
244         for_each_cpu_mask(j, online_policy_cpus) {
245                 /*
246                  * Support for SMP systems.
247                  * Make sure we are running on CPU that wants to change freq
248                  */
249                 cpus_clear(set_mask);
250                 if (policy->shared_type == CPUFREQ_SHARED_TYPE_ANY)
251                         cpus_or(set_mask, set_mask, online_policy_cpus);
252                 else
253                         cpu_set(j, set_mask);
254
255                 set_cpus_allowed(current, set_mask);
256                 if (unlikely(!cpu_isset(smp_processor_id(), set_mask))) {
257                         dprintk("couldn't limit to CPUs in this domain\n");
258                         result = -EAGAIN;
259                         break;
260                 }
261
262                 result = acpi_processor_set_performance (data, j, next_state);
263                 if (result) {
264                         result = -EAGAIN;
265                         break;
266                 }
267
268                 if (policy->shared_type == CPUFREQ_SHARED_TYPE_ANY)
269                         break;
270  
271                 cpu_set(j, covered_cpus);
272         }
273
274         for_each_cpu_mask(j, online_policy_cpus) {
275                 freqs.cpu = j;
276                 cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
277         }
278
279         if (unlikely(result)) {
280                 /*
281                  * We have failed halfway through the frequency change.
282                  * We have sent callbacks to online_policy_cpus and
283                  * acpi_processor_set_performance() has been called on 
284                  * coverd_cpus. Best effort undo..
285                  */
286
287                 if (!cpus_empty(covered_cpus)) {
288                         for_each_cpu_mask(j, covered_cpus) {
289                                 policy->cpu = j;
290                                 acpi_processor_set_performance (data, 
291                                                 j, 
292                                                 cur_state);
293                         }
294                 }
295
296                 tmp = freqs.new;
297                 freqs.new = freqs.old;
298                 freqs.old = tmp;
299                 for_each_cpu_mask(j, online_policy_cpus) {
300                         freqs.cpu = j;
301                         cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
302                         cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
303                 }
304         }
305
306         set_cpus_allowed(current, saved_mask);
307         return (result);
308 }
309
310
311 static int
312 acpi_cpufreq_verify (
313         struct cpufreq_policy   *policy)
314 {
315         unsigned int result = 0;
316         struct cpufreq_acpi_io *data = acpi_io_data[policy->cpu];
317
318         dprintk("acpi_cpufreq_verify\n");
319
320         result = cpufreq_frequency_table_verify(policy, 
321                         data->freq_table);
322
323         return (result);
324 }
325
326
327 static unsigned long
328 acpi_cpufreq_guess_freq (
329         struct cpufreq_acpi_io  *data,
330         unsigned int            cpu)
331 {
332         struct acpi_processor_performance       *perf = data->acpi_data;
333
334         if (cpu_khz) {
335                 /* search the closest match to cpu_khz */
336                 unsigned int i;
337                 unsigned long freq;
338                 unsigned long freqn = perf->states[0].core_frequency * 1000;
339
340                 for (i = 0; i < (perf->state_count - 1); i++) {
341                         freq = freqn;
342                         freqn = perf->states[i+1].core_frequency * 1000;
343                         if ((2 * cpu_khz) > (freqn + freq)) {
344                                 perf->state = i;
345                                 return (freq);
346                         }
347                 }
348                 perf->state = perf->state_count - 1;
349                 return (freqn);
350         } else {
351                 /* assume CPU is at P0... */
352                 perf->state = 0;
353                 return perf->states[0].core_frequency * 1000;
354         }
355 }
356
357
358 /*
359  * acpi_cpufreq_early_init - initialize ACPI P-States library
360  *
361  * Initialize the ACPI P-States library (drivers/acpi/processor_perflib.c)
362  * in order to determine correct frequency and voltage pairings. We can
363  * do _PDC and _PSD and find out the processor dependency for the
364  * actual init that will happen later...
365  */
366 static int acpi_cpufreq_early_init_acpi(void)
367 {
368         struct acpi_processor_performance       *data;
369         unsigned int                            i, j;
370
371         dprintk("acpi_cpufreq_early_init\n");
372
373         for_each_possible_cpu(i) {
374                 data = kzalloc(sizeof(struct acpi_processor_performance), 
375                         GFP_KERNEL);
376                 if (!data) {
377                         for_each_possible_cpu(j) {
378                                 kfree(acpi_perf_data[j]);
379                                 acpi_perf_data[j] = NULL;
380                         }
381                         return (-ENOMEM);
382                 }
383                 acpi_perf_data[i] = data;
384         }
385
386         /* Do initialization in ACPI core */
387         acpi_processor_preregister_performance(acpi_perf_data);
388         return 0;
389 }
390
391 static int
392 acpi_cpufreq_cpu_init (
393         struct cpufreq_policy   *policy)
394 {
395         unsigned int            i;
396         unsigned int            cpu = policy->cpu;
397         struct cpufreq_acpi_io  *data;
398         unsigned int            result = 0;
399         struct cpuinfo_x86 *c = &cpu_data[policy->cpu];
400         struct acpi_processor_performance       *perf;
401
402         dprintk("acpi_cpufreq_cpu_init\n");
403
404         if (!acpi_perf_data[cpu])
405                 return (-ENODEV);
406
407         data = kzalloc(sizeof(struct cpufreq_acpi_io), GFP_KERNEL);
408         if (!data)
409                 return (-ENOMEM);
410
411         data->acpi_data = acpi_perf_data[cpu];
412         acpi_io_data[cpu] = data;
413
414         result = acpi_processor_register_performance(data->acpi_data, cpu);
415
416         if (result)
417                 goto err_free;
418
419         perf = data->acpi_data;
420         policy->cpus = perf->shared_cpu_map;
421         policy->shared_type = perf->shared_type;
422
423         if (cpu_has(c, X86_FEATURE_CONSTANT_TSC)) {
424                 acpi_cpufreq_driver.flags |= CPUFREQ_CONST_LOOPS;
425         }
426
427         /* capability check */
428         if (perf->state_count <= 1) {
429                 dprintk("No P-States\n");
430                 result = -ENODEV;
431                 goto err_unreg;
432         }
433
434         if ((perf->control_register.space_id != ACPI_ADR_SPACE_SYSTEM_IO) ||
435             (perf->status_register.space_id != ACPI_ADR_SPACE_SYSTEM_IO)) {
436                 dprintk("Unsupported address space [%d, %d]\n",
437                         (u32) (perf->control_register.space_id),
438                         (u32) (perf->status_register.space_id));
439                 result = -ENODEV;
440                 goto err_unreg;
441         }
442
443         /* alloc freq_table */
444         data->freq_table = kmalloc(sizeof(struct cpufreq_frequency_table) * (perf->state_count + 1), GFP_KERNEL);
445         if (!data->freq_table) {
446                 result = -ENOMEM;
447                 goto err_unreg;
448         }
449
450         /* detect transition latency */
451         policy->cpuinfo.transition_latency = 0;
452         for (i=0; i<perf->state_count; i++) {
453                 if ((perf->states[i].transition_latency * 1000) > policy->cpuinfo.transition_latency)
454                         policy->cpuinfo.transition_latency = perf->states[i].transition_latency * 1000;
455         }
456         policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
457
458         /* The current speed is unknown and not detectable by ACPI...  */
459         policy->cur = acpi_cpufreq_guess_freq(data, policy->cpu);
460
461         /* table init */
462         for (i=0; i<=perf->state_count; i++)
463         {
464                 data->freq_table[i].index = i;
465                 if (i<perf->state_count)
466                         data->freq_table[i].frequency = perf->states[i].core_frequency * 1000;
467                 else
468                         data->freq_table[i].frequency = CPUFREQ_TABLE_END;
469         }
470
471         result = cpufreq_frequency_table_cpuinfo(policy, data->freq_table);
472         if (result) {
473                 goto err_freqfree;
474         }
475
476         /* notify BIOS that we exist */
477         acpi_processor_notify_smm(THIS_MODULE);
478
479         printk(KERN_INFO "acpi-cpufreq: CPU%u - ACPI performance management activated.\n",
480                cpu);
481         for (i = 0; i < perf->state_count; i++)
482                 dprintk("     %cP%d: %d MHz, %d mW, %d uS\n",
483                         (i == perf->state?'*':' '), i,
484                         (u32) perf->states[i].core_frequency,
485                         (u32) perf->states[i].power,
486                         (u32) perf->states[i].transition_latency);
487
488         cpufreq_frequency_table_get_attr(data->freq_table, policy->cpu);
489         
490         /*
491          * the first call to ->target() should result in us actually
492          * writing something to the appropriate registers.
493          */
494         data->resume = 1;
495         
496         return (result);
497
498  err_freqfree:
499         kfree(data->freq_table);
500  err_unreg:
501         acpi_processor_unregister_performance(perf, cpu);
502  err_free:
503         kfree(data);
504         acpi_io_data[cpu] = NULL;
505
506         return (result);
507 }
508
509
510 static int
511 acpi_cpufreq_cpu_exit (
512         struct cpufreq_policy   *policy)
513 {
514         struct cpufreq_acpi_io *data = acpi_io_data[policy->cpu];
515
516
517         dprintk("acpi_cpufreq_cpu_exit\n");
518
519         if (data) {
520                 cpufreq_frequency_table_put_attr(policy->cpu);
521                 acpi_io_data[policy->cpu] = NULL;
522                 acpi_processor_unregister_performance(data->acpi_data, policy->cpu);
523                 kfree(data);
524         }
525
526         return (0);
527 }
528
529 static int
530 acpi_cpufreq_resume (
531         struct cpufreq_policy   *policy)
532 {
533         struct cpufreq_acpi_io *data = acpi_io_data[policy->cpu];
534
535
536         dprintk("acpi_cpufreq_resume\n");
537
538         data->resume = 1;
539
540         return (0);
541 }
542
543
544 static struct freq_attr* acpi_cpufreq_attr[] = {
545         &cpufreq_freq_attr_scaling_available_freqs,
546         NULL,
547 };
548
549 static struct cpufreq_driver acpi_cpufreq_driver = {
550         .verify = acpi_cpufreq_verify,
551         .target = acpi_cpufreq_target,
552         .init   = acpi_cpufreq_cpu_init,
553         .exit   = acpi_cpufreq_cpu_exit,
554         .resume = acpi_cpufreq_resume,
555         .name   = "acpi-cpufreq",
556         .owner  = THIS_MODULE,
557         .attr   = acpi_cpufreq_attr,
558         .flags  = CPUFREQ_STICKY,
559 };
560
561
562 static int __init
563 acpi_cpufreq_init (void)
564 {
565         int                     result = 0;
566
567         dprintk("acpi_cpufreq_init\n");
568
569         result = acpi_cpufreq_early_init_acpi();
570
571         if (!result)
572                 result = cpufreq_register_driver(&acpi_cpufreq_driver);
573         
574         return (result);
575 }
576
577
578 static void __exit
579 acpi_cpufreq_exit (void)
580 {
581         unsigned int    i;
582         dprintk("acpi_cpufreq_exit\n");
583
584         cpufreq_unregister_driver(&acpi_cpufreq_driver);
585
586         for_each_possible_cpu(i) {
587                 kfree(acpi_perf_data[i]);
588                 acpi_perf_data[i] = NULL;
589         }
590         return;
591 }
592
593 module_param(acpi_pstate_strict, uint, 0644);
594 MODULE_PARM_DESC(acpi_pstate_strict, "value 0 or non-zero. non-zero -> strict ACPI checks are performed during frequency changes.");
595
596 late_initcall(acpi_cpufreq_init);
597 module_exit(acpi_cpufreq_exit);
598
599 MODULE_ALIAS("acpi");