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