Commit | Line | Data |
---|---|---|
1da177e4 LT |
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 <asm/io.h> | |
35 | #include <asm/delay.h> | |
36 | #include <asm/uaccess.h> | |
37 | ||
38 | #include <linux/acpi.h> | |
39 | #include <acpi/processor.h> | |
40 | ||
41 | #include "speedstep-est-common.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 | ||
58 | static struct cpufreq_driver acpi_cpufreq_driver; | |
59 | ||
60 | static int | |
61 | acpi_processor_write_port( | |
62 | u16 port, | |
63 | u8 bit_width, | |
64 | u32 value) | |
65 | { | |
66 | if (bit_width <= 8) { | |
67 | outb(value, port); | |
68 | } else if (bit_width <= 16) { | |
69 | outw(value, port); | |
70 | } else if (bit_width <= 32) { | |
71 | outl(value, port); | |
72 | } else { | |
73 | return -ENODEV; | |
74 | } | |
75 | return 0; | |
76 | } | |
77 | ||
78 | static int | |
79 | acpi_processor_read_port( | |
80 | u16 port, | |
81 | u8 bit_width, | |
82 | u32 *ret) | |
83 | { | |
84 | *ret = 0; | |
85 | if (bit_width <= 8) { | |
86 | *ret = inb(port); | |
87 | } else if (bit_width <= 16) { | |
88 | *ret = inw(port); | |
89 | } else if (bit_width <= 32) { | |
90 | *ret = inl(port); | |
91 | } else { | |
92 | return -ENODEV; | |
93 | } | |
94 | return 0; | |
95 | } | |
96 | ||
97 | static int | |
98 | acpi_processor_set_performance ( | |
99 | struct cpufreq_acpi_io *data, | |
100 | unsigned int cpu, | |
101 | int state) | |
102 | { | |
103 | u16 port = 0; | |
104 | u8 bit_width = 0; | |
105 | int ret = 0; | |
106 | u32 value = 0; | |
107 | int i = 0; | |
108 | struct cpufreq_freqs cpufreq_freqs; | |
109 | cpumask_t saved_mask; | |
110 | int retval; | |
111 | ||
112 | dprintk("acpi_processor_set_performance\n"); | |
113 | ||
114 | /* | |
115 | * TBD: Use something other than set_cpus_allowed. | |
116 | * As set_cpus_allowed is a bit racy, | |
117 | * with any other set_cpus_allowed for this process. | |
118 | */ | |
119 | saved_mask = current->cpus_allowed; | |
120 | set_cpus_allowed(current, cpumask_of_cpu(cpu)); | |
121 | if (smp_processor_id() != cpu) { | |
122 | return (-EAGAIN); | |
123 | } | |
124 | ||
125 | if (state == data->acpi_data.state) { | |
126 | if (unlikely(data->resume)) { | |
127 | dprintk("Called after resume, resetting to P%d\n", state); | |
128 | data->resume = 0; | |
129 | } else { | |
130 | dprintk("Already at target state (P%d)\n", state); | |
131 | retval = 0; | |
132 | goto migrate_end; | |
133 | } | |
134 | } | |
135 | ||
136 | dprintk("Transitioning from P%d to P%d\n", | |
137 | data->acpi_data.state, state); | |
138 | ||
139 | /* cpufreq frequency struct */ | |
140 | cpufreq_freqs.cpu = cpu; | |
141 | cpufreq_freqs.old = data->freq_table[data->acpi_data.state].frequency; | |
142 | cpufreq_freqs.new = data->freq_table[state].frequency; | |
143 | ||
144 | /* notify cpufreq */ | |
145 | cpufreq_notify_transition(&cpufreq_freqs, CPUFREQ_PRECHANGE); | |
146 | ||
147 | /* | |
148 | * First we write the target state's 'control' value to the | |
149 | * control_register. | |
150 | */ | |
151 | ||
152 | port = data->acpi_data.control_register.address; | |
153 | bit_width = data->acpi_data.control_register.bit_width; | |
154 | value = (u32) data->acpi_data.states[state].control; | |
155 | ||
156 | dprintk("Writing 0x%08x to port 0x%04x\n", value, port); | |
157 | ||
158 | ret = acpi_processor_write_port(port, bit_width, value); | |
159 | if (ret) { | |
160 | dprintk("Invalid port width 0x%04x\n", bit_width); | |
161 | retval = ret; | |
162 | goto migrate_end; | |
163 | } | |
164 | ||
165 | /* | |
166 | * Then we read the 'status_register' and compare the value with the | |
167 | * target state's 'status' to make sure the transition was successful. | |
168 | * Note that we'll poll for up to 1ms (100 cycles of 10us) before | |
169 | * giving up. | |
170 | */ | |
171 | ||
172 | port = data->acpi_data.status_register.address; | |
173 | bit_width = data->acpi_data.status_register.bit_width; | |
174 | ||
175 | dprintk("Looking for 0x%08x from port 0x%04x\n", | |
176 | (u32) data->acpi_data.states[state].status, port); | |
177 | ||
178 | for (i=0; i<100; i++) { | |
179 | ret = acpi_processor_read_port(port, bit_width, &value); | |
180 | if (ret) { | |
181 | dprintk("Invalid port width 0x%04x\n", bit_width); | |
182 | retval = ret; | |
183 | goto migrate_end; | |
184 | } | |
185 | if (value == (u32) data->acpi_data.states[state].status) | |
186 | break; | |
187 | udelay(10); | |
188 | } | |
189 | ||
190 | /* notify cpufreq */ | |
191 | cpufreq_notify_transition(&cpufreq_freqs, CPUFREQ_POSTCHANGE); | |
192 | ||
193 | if (value != (u32) data->acpi_data.states[state].status) { | |
194 | unsigned int tmp = cpufreq_freqs.new; | |
195 | cpufreq_freqs.new = cpufreq_freqs.old; | |
196 | cpufreq_freqs.old = tmp; | |
197 | cpufreq_notify_transition(&cpufreq_freqs, CPUFREQ_PRECHANGE); | |
198 | cpufreq_notify_transition(&cpufreq_freqs, CPUFREQ_POSTCHANGE); | |
199 | printk(KERN_WARNING "acpi-cpufreq: Transition failed\n"); | |
200 | retval = -ENODEV; | |
201 | goto migrate_end; | |
202 | } | |
203 | ||
204 | dprintk("Transition successful after %d microseconds\n", i * 10); | |
205 | ||
206 | data->acpi_data.state = state; | |
207 | ||
208 | retval = 0; | |
209 | migrate_end: | |
210 | set_cpus_allowed(current, saved_mask); | |
211 | return (retval); | |
212 | } | |
213 | ||
214 | ||
215 | static int | |
216 | acpi_cpufreq_target ( | |
217 | struct cpufreq_policy *policy, | |
218 | unsigned int target_freq, | |
219 | unsigned int relation) | |
220 | { | |
221 | struct cpufreq_acpi_io *data = acpi_io_data[policy->cpu]; | |
222 | unsigned int next_state = 0; | |
223 | unsigned int result = 0; | |
224 | ||
225 | dprintk("acpi_cpufreq_setpolicy\n"); | |
226 | ||
227 | result = cpufreq_frequency_table_target(policy, | |
228 | data->freq_table, | |
229 | target_freq, | |
230 | relation, | |
231 | &next_state); | |
232 | if (result) | |
233 | return (result); | |
234 | ||
235 | result = acpi_processor_set_performance (data, policy->cpu, next_state); | |
236 | ||
237 | return (result); | |
238 | } | |
239 | ||
240 | ||
241 | static int | |
242 | acpi_cpufreq_verify ( | |
243 | struct cpufreq_policy *policy) | |
244 | { | |
245 | unsigned int result = 0; | |
246 | struct cpufreq_acpi_io *data = acpi_io_data[policy->cpu]; | |
247 | ||
248 | dprintk("acpi_cpufreq_verify\n"); | |
249 | ||
250 | result = cpufreq_frequency_table_verify(policy, | |
251 | data->freq_table); | |
252 | ||
253 | return (result); | |
254 | } | |
255 | ||
256 | ||
257 | static unsigned long | |
258 | acpi_cpufreq_guess_freq ( | |
259 | struct cpufreq_acpi_io *data, | |
260 | unsigned int cpu) | |
261 | { | |
262 | if (cpu_khz) { | |
263 | /* search the closest match to cpu_khz */ | |
264 | unsigned int i; | |
265 | unsigned long freq; | |
266 | unsigned long freqn = data->acpi_data.states[0].core_frequency * 1000; | |
267 | ||
268 | for (i=0; i < (data->acpi_data.state_count - 1); i++) { | |
269 | freq = freqn; | |
270 | freqn = data->acpi_data.states[i+1].core_frequency * 1000; | |
271 | if ((2 * cpu_khz) > (freqn + freq)) { | |
272 | data->acpi_data.state = i; | |
273 | return (freq); | |
274 | } | |
275 | } | |
276 | data->acpi_data.state = data->acpi_data.state_count - 1; | |
277 | return (freqn); | |
278 | } else | |
279 | /* assume CPU is at P0... */ | |
280 | data->acpi_data.state = 0; | |
281 | return data->acpi_data.states[0].core_frequency * 1000; | |
282 | ||
283 | } | |
284 | ||
285 | ||
286 | /* | |
287 | * acpi_processor_cpu_init_pdc_est - let BIOS know about the SMP capabilities | |
288 | * of this driver | |
289 | * @perf: processor-specific acpi_io_data struct | |
290 | * @cpu: CPU being initialized | |
291 | * | |
292 | * To avoid issues with legacy OSes, some BIOSes require to be informed of | |
293 | * the SMP capabilities of OS P-state driver. Here we set the bits in _PDC | |
294 | * accordingly, for Enhanced Speedstep. Actual call to _PDC is done in | |
295 | * driver/acpi/processor.c | |
296 | */ | |
297 | static void | |
298 | acpi_processor_cpu_init_pdc_est( | |
299 | struct acpi_processor_performance *perf, | |
300 | unsigned int cpu, | |
301 | struct acpi_object_list *obj_list | |
302 | ) | |
303 | { | |
304 | union acpi_object *obj; | |
305 | u32 *buf; | |
306 | struct cpuinfo_x86 *c = cpu_data + cpu; | |
307 | dprintk("acpi_processor_cpu_init_pdc_est\n"); | |
308 | ||
309 | if (!cpu_has(c, X86_FEATURE_EST)) | |
310 | return; | |
311 | ||
312 | /* Initialize pdc. It will be used later. */ | |
313 | if (!obj_list) | |
314 | return; | |
315 | ||
316 | if (!(obj_list->count && obj_list->pointer)) | |
317 | return; | |
318 | ||
319 | obj = obj_list->pointer; | |
320 | if ((obj->buffer.length == 12) && obj->buffer.pointer) { | |
321 | buf = (u32 *)obj->buffer.pointer; | |
322 | buf[0] = ACPI_PDC_REVISION_ID; | |
323 | buf[1] = 1; | |
324 | buf[2] = ACPI_PDC_EST_CAPABILITY_SMP; | |
325 | perf->pdc = obj_list; | |
326 | } | |
327 | return; | |
328 | } | |
329 | ||
330 | ||
331 | /* CPU specific PDC initialization */ | |
332 | static void | |
333 | acpi_processor_cpu_init_pdc( | |
334 | struct acpi_processor_performance *perf, | |
335 | unsigned int cpu, | |
336 | struct acpi_object_list *obj_list | |
337 | ) | |
338 | { | |
339 | struct cpuinfo_x86 *c = cpu_data + cpu; | |
340 | dprintk("acpi_processor_cpu_init_pdc\n"); | |
341 | perf->pdc = NULL; | |
342 | if (cpu_has(c, X86_FEATURE_EST)) | |
343 | acpi_processor_cpu_init_pdc_est(perf, cpu, obj_list); | |
344 | return; | |
345 | } | |
346 | ||
347 | ||
348 | static int | |
349 | acpi_cpufreq_cpu_init ( | |
350 | struct cpufreq_policy *policy) | |
351 | { | |
352 | unsigned int i; | |
353 | unsigned int cpu = policy->cpu; | |
354 | struct cpufreq_acpi_io *data; | |
355 | unsigned int result = 0; | |
356 | ||
357 | union acpi_object arg0 = {ACPI_TYPE_BUFFER}; | |
358 | u32 arg0_buf[3]; | |
359 | struct acpi_object_list arg_list = {1, &arg0}; | |
360 | ||
361 | dprintk("acpi_cpufreq_cpu_init\n"); | |
362 | /* setup arg_list for _PDC settings */ | |
363 | arg0.buffer.length = 12; | |
364 | arg0.buffer.pointer = (u8 *) arg0_buf; | |
365 | ||
366 | data = kmalloc(sizeof(struct cpufreq_acpi_io), GFP_KERNEL); | |
367 | if (!data) | |
368 | return (-ENOMEM); | |
369 | memset(data, 0, sizeof(struct cpufreq_acpi_io)); | |
370 | ||
371 | acpi_io_data[cpu] = data; | |
372 | ||
373 | acpi_processor_cpu_init_pdc(&data->acpi_data, cpu, &arg_list); | |
374 | result = acpi_processor_register_performance(&data->acpi_data, cpu); | |
375 | data->acpi_data.pdc = NULL; | |
376 | ||
377 | if (result) | |
378 | goto err_free; | |
379 | ||
380 | if (is_const_loops_cpu(cpu)) { | |
381 | acpi_cpufreq_driver.flags |= CPUFREQ_CONST_LOOPS; | |
382 | } | |
383 | ||
384 | /* capability check */ | |
385 | if (data->acpi_data.state_count <= 1) { | |
386 | dprintk("No P-States\n"); | |
387 | result = -ENODEV; | |
388 | goto err_unreg; | |
389 | } | |
390 | if ((data->acpi_data.control_register.space_id != ACPI_ADR_SPACE_SYSTEM_IO) || | |
391 | (data->acpi_data.status_register.space_id != ACPI_ADR_SPACE_SYSTEM_IO)) { | |
392 | dprintk("Unsupported address space [%d, %d]\n", | |
393 | (u32) (data->acpi_data.control_register.space_id), | |
394 | (u32) (data->acpi_data.status_register.space_id)); | |
395 | result = -ENODEV; | |
396 | goto err_unreg; | |
397 | } | |
398 | ||
399 | /* alloc freq_table */ | |
400 | data->freq_table = kmalloc(sizeof(struct cpufreq_frequency_table) * (data->acpi_data.state_count + 1), GFP_KERNEL); | |
401 | if (!data->freq_table) { | |
402 | result = -ENOMEM; | |
403 | goto err_unreg; | |
404 | } | |
405 | ||
406 | /* detect transition latency */ | |
407 | policy->cpuinfo.transition_latency = 0; | |
408 | for (i=0; i<data->acpi_data.state_count; i++) { | |
409 | if ((data->acpi_data.states[i].transition_latency * 1000) > policy->cpuinfo.transition_latency) | |
410 | policy->cpuinfo.transition_latency = data->acpi_data.states[i].transition_latency * 1000; | |
411 | } | |
412 | policy->governor = CPUFREQ_DEFAULT_GOVERNOR; | |
413 | ||
414 | /* The current speed is unknown and not detectable by ACPI... */ | |
415 | policy->cur = acpi_cpufreq_guess_freq(data, policy->cpu); | |
416 | ||
417 | /* table init */ | |
418 | for (i=0; i<=data->acpi_data.state_count; i++) | |
419 | { | |
420 | data->freq_table[i].index = i; | |
421 | if (i<data->acpi_data.state_count) | |
422 | data->freq_table[i].frequency = data->acpi_data.states[i].core_frequency * 1000; | |
423 | else | |
424 | data->freq_table[i].frequency = CPUFREQ_TABLE_END; | |
425 | } | |
426 | ||
427 | result = cpufreq_frequency_table_cpuinfo(policy, data->freq_table); | |
428 | if (result) { | |
429 | goto err_freqfree; | |
430 | } | |
431 | ||
432 | /* notify BIOS that we exist */ | |
433 | acpi_processor_notify_smm(THIS_MODULE); | |
434 | ||
435 | printk(KERN_INFO "acpi-cpufreq: CPU%u - ACPI performance management activated.\n", | |
436 | cpu); | |
437 | for (i = 0; i < data->acpi_data.state_count; i++) | |
438 | dprintk(" %cP%d: %d MHz, %d mW, %d uS\n", | |
439 | (i == data->acpi_data.state?'*':' '), i, | |
440 | (u32) data->acpi_data.states[i].core_frequency, | |
441 | (u32) data->acpi_data.states[i].power, | |
442 | (u32) data->acpi_data.states[i].transition_latency); | |
443 | ||
444 | cpufreq_frequency_table_get_attr(data->freq_table, policy->cpu); | |
4b31e774 DB |
445 | |
446 | /* | |
447 | * the first call to ->target() should result in us actually | |
448 | * writing something to the appropriate registers. | |
449 | */ | |
450 | data->resume = 1; | |
451 | ||
1da177e4 LT |
452 | return (result); |
453 | ||
454 | err_freqfree: | |
455 | kfree(data->freq_table); | |
456 | err_unreg: | |
457 | acpi_processor_unregister_performance(&data->acpi_data, cpu); | |
458 | err_free: | |
459 | kfree(data); | |
460 | acpi_io_data[cpu] = NULL; | |
461 | ||
462 | return (result); | |
463 | } | |
464 | ||
465 | ||
466 | static int | |
467 | acpi_cpufreq_cpu_exit ( | |
468 | struct cpufreq_policy *policy) | |
469 | { | |
470 | struct cpufreq_acpi_io *data = acpi_io_data[policy->cpu]; | |
471 | ||
472 | ||
473 | dprintk("acpi_cpufreq_cpu_exit\n"); | |
474 | ||
475 | if (data) { | |
476 | cpufreq_frequency_table_put_attr(policy->cpu); | |
477 | acpi_io_data[policy->cpu] = NULL; | |
478 | acpi_processor_unregister_performance(&data->acpi_data, policy->cpu); | |
479 | kfree(data); | |
480 | } | |
481 | ||
482 | return (0); | |
483 | } | |
484 | ||
485 | static int | |
486 | acpi_cpufreq_resume ( | |
487 | struct cpufreq_policy *policy) | |
488 | { | |
489 | struct cpufreq_acpi_io *data = acpi_io_data[policy->cpu]; | |
490 | ||
491 | ||
492 | dprintk("acpi_cpufreq_resume\n"); | |
493 | ||
494 | data->resume = 1; | |
495 | ||
496 | return (0); | |
497 | } | |
498 | ||
499 | ||
500 | static struct freq_attr* acpi_cpufreq_attr[] = { | |
501 | &cpufreq_freq_attr_scaling_available_freqs, | |
502 | NULL, | |
503 | }; | |
504 | ||
505 | static struct cpufreq_driver acpi_cpufreq_driver = { | |
506 | .verify = acpi_cpufreq_verify, | |
507 | .target = acpi_cpufreq_target, | |
508 | .init = acpi_cpufreq_cpu_init, | |
509 | .exit = acpi_cpufreq_cpu_exit, | |
510 | .resume = acpi_cpufreq_resume, | |
511 | .name = "acpi-cpufreq", | |
512 | .owner = THIS_MODULE, | |
513 | .attr = acpi_cpufreq_attr, | |
514 | }; | |
515 | ||
516 | ||
517 | static int __init | |
518 | acpi_cpufreq_init (void) | |
519 | { | |
520 | int result = 0; | |
521 | ||
522 | dprintk("acpi_cpufreq_init\n"); | |
523 | ||
524 | result = cpufreq_register_driver(&acpi_cpufreq_driver); | |
525 | ||
526 | return (result); | |
527 | } | |
528 | ||
529 | ||
530 | static void __exit | |
531 | acpi_cpufreq_exit (void) | |
532 | { | |
533 | dprintk("acpi_cpufreq_exit\n"); | |
534 | ||
535 | cpufreq_unregister_driver(&acpi_cpufreq_driver); | |
536 | ||
537 | return; | |
538 | } | |
539 | ||
540 | ||
541 | late_initcall(acpi_cpufreq_init); | |
542 | module_exit(acpi_cpufreq_exit); | |
543 | ||
544 | MODULE_ALIAS("acpi"); |