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1da177e4 LT |
1 | /* |
2 | * processor_idle - idle state submodule to the ACPI processor driver | |
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 | * This program is free software; you can redistribute it and/or modify | |
13 | * it under the terms of the GNU General Public License as published by | |
14 | * the Free Software Foundation; either version 2 of the License, or (at | |
15 | * your option) any later version. | |
16 | * | |
17 | * This program is distributed in the hope that it will be useful, but | |
18 | * WITHOUT ANY WARRANTY; without even the implied warranty of | |
19 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
20 | * General Public License for more details. | |
21 | * | |
22 | * You should have received a copy of the GNU General Public License along | |
23 | * with this program; if not, write to the Free Software Foundation, Inc., | |
24 | * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. | |
25 | * | |
26 | * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ | |
27 | */ | |
28 | ||
29 | #include <linux/kernel.h> | |
30 | #include <linux/module.h> | |
31 | #include <linux/init.h> | |
32 | #include <linux/cpufreq.h> | |
33 | #include <linux/proc_fs.h> | |
34 | #include <linux/seq_file.h> | |
35 | #include <linux/acpi.h> | |
36 | #include <linux/dmi.h> | |
37 | #include <linux/moduleparam.h> | |
38 | ||
39 | #include <asm/io.h> | |
40 | #include <asm/uaccess.h> | |
41 | ||
42 | #include <acpi/acpi_bus.h> | |
43 | #include <acpi/processor.h> | |
44 | ||
45 | #define ACPI_PROCESSOR_COMPONENT 0x01000000 | |
46 | #define ACPI_PROCESSOR_CLASS "processor" | |
47 | #define ACPI_PROCESSOR_DRIVER_NAME "ACPI Processor Driver" | |
48 | #define _COMPONENT ACPI_PROCESSOR_COMPONENT | |
49 | ACPI_MODULE_NAME ("acpi_processor") | |
50 | ||
51 | #define ACPI_PROCESSOR_FILE_POWER "power" | |
52 | ||
53 | #define US_TO_PM_TIMER_TICKS(t) ((t * (PM_TIMER_FREQUENCY/1000)) / 1000) | |
54 | #define C2_OVERHEAD 4 /* 1us (3.579 ticks per us) */ | |
55 | #define C3_OVERHEAD 4 /* 1us (3.579 ticks per us) */ | |
56 | ||
57 | static void (*pm_idle_save)(void); | |
58 | module_param(max_cstate, uint, 0644); | |
59 | ||
60 | static unsigned int nocst = 0; | |
61 | module_param(nocst, uint, 0000); | |
62 | ||
63 | /* | |
64 | * bm_history -- bit-mask with a bit per jiffy of bus-master activity | |
65 | * 1000 HZ: 0xFFFFFFFF: 32 jiffies = 32ms | |
66 | * 800 HZ: 0xFFFFFFFF: 32 jiffies = 40ms | |
67 | * 100 HZ: 0x0000000F: 4 jiffies = 40ms | |
68 | * reduce history for more aggressive entry into C3 | |
69 | */ | |
70 | static unsigned int bm_history = (HZ >= 800 ? 0xFFFFFFFF : ((1U << (HZ / 25)) - 1)); | |
71 | module_param(bm_history, uint, 0644); | |
72 | /* -------------------------------------------------------------------------- | |
73 | Power Management | |
74 | -------------------------------------------------------------------------- */ | |
75 | ||
76 | /* | |
77 | * IBM ThinkPad R40e crashes mysteriously when going into C2 or C3. | |
78 | * For now disable this. Probably a bug somewhere else. | |
79 | * | |
80 | * To skip this limit, boot/load with a large max_cstate limit. | |
81 | */ | |
82 | static int no_c2c3(struct dmi_system_id *id) | |
83 | { | |
84 | if (max_cstate > ACPI_PROCESSOR_MAX_POWER) | |
85 | return 0; | |
86 | ||
87 | printk(KERN_NOTICE PREFIX "%s detected - C2,C3 disabled." | |
88 | " Override with \"processor.max_cstate=%d\"\n", id->ident, | |
89 | ACPI_PROCESSOR_MAX_POWER + 1); | |
90 | ||
91 | max_cstate = 1; | |
92 | ||
93 | return 0; | |
94 | } | |
95 | ||
96 | ||
97 | ||
98 | ||
99 | static struct dmi_system_id __initdata processor_power_dmi_table[] = { | |
100 | { no_c2c3, "IBM ThinkPad R40e", { | |
101 | DMI_MATCH(DMI_BIOS_VENDOR,"IBM"), | |
102 | DMI_MATCH(DMI_BIOS_VERSION,"1SET60WW") }}, | |
103 | { no_c2c3, "Medion 41700", { | |
104 | DMI_MATCH(DMI_BIOS_VENDOR,"Phoenix Technologies LTD"), | |
105 | DMI_MATCH(DMI_BIOS_VERSION,"R01-A1J") }}, | |
106 | {}, | |
107 | }; | |
108 | ||
109 | ||
110 | static inline u32 | |
111 | ticks_elapsed ( | |
112 | u32 t1, | |
113 | u32 t2) | |
114 | { | |
115 | if (t2 >= t1) | |
116 | return (t2 - t1); | |
117 | else if (!acpi_fadt.tmr_val_ext) | |
118 | return (((0x00FFFFFF - t1) + t2) & 0x00FFFFFF); | |
119 | else | |
120 | return ((0xFFFFFFFF - t1) + t2); | |
121 | } | |
122 | ||
123 | ||
124 | static void | |
125 | acpi_processor_power_activate ( | |
126 | struct acpi_processor *pr, | |
127 | struct acpi_processor_cx *new) | |
128 | { | |
129 | struct acpi_processor_cx *old; | |
130 | ||
131 | if (!pr || !new) | |
132 | return; | |
133 | ||
134 | old = pr->power.state; | |
135 | ||
136 | if (old) | |
137 | old->promotion.count = 0; | |
138 | new->demotion.count = 0; | |
139 | ||
140 | /* Cleanup from old state. */ | |
141 | if (old) { | |
142 | switch (old->type) { | |
143 | case ACPI_STATE_C3: | |
144 | /* Disable bus master reload */ | |
145 | if (new->type != ACPI_STATE_C3) | |
146 | acpi_set_register(ACPI_BITREG_BUS_MASTER_RLD, 0, ACPI_MTX_DO_NOT_LOCK); | |
147 | break; | |
148 | } | |
149 | } | |
150 | ||
151 | /* Prepare to use new state. */ | |
152 | switch (new->type) { | |
153 | case ACPI_STATE_C3: | |
154 | /* Enable bus master reload */ | |
155 | if (old->type != ACPI_STATE_C3) | |
156 | acpi_set_register(ACPI_BITREG_BUS_MASTER_RLD, 1, ACPI_MTX_DO_NOT_LOCK); | |
157 | break; | |
158 | } | |
159 | ||
160 | pr->power.state = new; | |
161 | ||
162 | return; | |
163 | } | |
164 | ||
165 | ||
166 | static void acpi_processor_idle (void) | |
167 | { | |
168 | struct acpi_processor *pr = NULL; | |
169 | struct acpi_processor_cx *cx = NULL; | |
170 | struct acpi_processor_cx *next_state = NULL; | |
171 | int sleep_ticks = 0; | |
172 | u32 t1, t2 = 0; | |
173 | ||
174 | pr = processors[_smp_processor_id()]; | |
175 | if (!pr) | |
176 | return; | |
177 | ||
178 | /* | |
179 | * Interrupts must be disabled during bus mastering calculations and | |
180 | * for C2/C3 transitions. | |
181 | */ | |
182 | local_irq_disable(); | |
183 | ||
184 | /* | |
185 | * Check whether we truly need to go idle, or should | |
186 | * reschedule: | |
187 | */ | |
188 | if (unlikely(need_resched())) { | |
189 | local_irq_enable(); | |
190 | return; | |
191 | } | |
192 | ||
193 | cx = pr->power.state; | |
194 | if (!cx) | |
195 | goto easy_out; | |
196 | ||
197 | /* | |
198 | * Check BM Activity | |
199 | * ----------------- | |
200 | * Check for bus mastering activity (if required), record, and check | |
201 | * for demotion. | |
202 | */ | |
203 | if (pr->flags.bm_check) { | |
204 | u32 bm_status = 0; | |
205 | unsigned long diff = jiffies - pr->power.bm_check_timestamp; | |
206 | ||
207 | if (diff > 32) | |
208 | diff = 32; | |
209 | ||
210 | while (diff) { | |
211 | /* if we didn't get called, assume there was busmaster activity */ | |
212 | diff--; | |
213 | if (diff) | |
214 | pr->power.bm_activity |= 0x1; | |
215 | pr->power.bm_activity <<= 1; | |
216 | } | |
217 | ||
218 | acpi_get_register(ACPI_BITREG_BUS_MASTER_STATUS, | |
219 | &bm_status, ACPI_MTX_DO_NOT_LOCK); | |
220 | if (bm_status) { | |
221 | pr->power.bm_activity++; | |
222 | acpi_set_register(ACPI_BITREG_BUS_MASTER_STATUS, | |
223 | 1, ACPI_MTX_DO_NOT_LOCK); | |
224 | } | |
225 | /* | |
226 | * PIIX4 Erratum #18: Note that BM_STS doesn't always reflect | |
227 | * the true state of bus mastering activity; forcing us to | |
228 | * manually check the BMIDEA bit of each IDE channel. | |
229 | */ | |
230 | else if (errata.piix4.bmisx) { | |
231 | if ((inb_p(errata.piix4.bmisx + 0x02) & 0x01) | |
232 | || (inb_p(errata.piix4.bmisx + 0x0A) & 0x01)) | |
233 | pr->power.bm_activity++; | |
234 | } | |
235 | ||
236 | pr->power.bm_check_timestamp = jiffies; | |
237 | ||
238 | /* | |
239 | * Apply bus mastering demotion policy. Automatically demote | |
240 | * to avoid a faulty transition. Note that the processor | |
241 | * won't enter a low-power state during this call (to this | |
242 | * funciton) but should upon the next. | |
243 | * | |
244 | * TBD: A better policy might be to fallback to the demotion | |
245 | * state (use it for this quantum only) istead of | |
246 | * demoting -- and rely on duration as our sole demotion | |
247 | * qualification. This may, however, introduce DMA | |
248 | * issues (e.g. floppy DMA transfer overrun/underrun). | |
249 | */ | |
250 | if (pr->power.bm_activity & cx->demotion.threshold.bm) { | |
251 | local_irq_enable(); | |
252 | next_state = cx->demotion.state; | |
253 | goto end; | |
254 | } | |
255 | } | |
256 | ||
257 | cx->usage++; | |
258 | ||
259 | /* | |
260 | * Sleep: | |
261 | * ------ | |
262 | * Invoke the current Cx state to put the processor to sleep. | |
263 | */ | |
264 | switch (cx->type) { | |
265 | ||
266 | case ACPI_STATE_C1: | |
267 | /* | |
268 | * Invoke C1. | |
269 | * Use the appropriate idle routine, the one that would | |
270 | * be used without acpi C-states. | |
271 | */ | |
272 | if (pm_idle_save) | |
273 | pm_idle_save(); | |
274 | else | |
275 | safe_halt(); | |
276 | /* | |
277 | * TBD: Can't get time duration while in C1, as resumes | |
278 | * go to an ISR rather than here. Need to instrument | |
279 | * base interrupt handler. | |
280 | */ | |
281 | sleep_ticks = 0xFFFFFFFF; | |
282 | break; | |
283 | ||
284 | case ACPI_STATE_C2: | |
285 | /* Get start time (ticks) */ | |
286 | t1 = inl(acpi_fadt.xpm_tmr_blk.address); | |
287 | /* Invoke C2 */ | |
288 | inb(cx->address); | |
289 | /* Dummy op - must do something useless after P_LVL2 read */ | |
290 | t2 = inl(acpi_fadt.xpm_tmr_blk.address); | |
291 | /* Get end time (ticks) */ | |
292 | t2 = inl(acpi_fadt.xpm_tmr_blk.address); | |
293 | /* Re-enable interrupts */ | |
294 | local_irq_enable(); | |
295 | /* Compute time (ticks) that we were actually asleep */ | |
296 | sleep_ticks = ticks_elapsed(t1, t2) - cx->latency_ticks - C2_OVERHEAD; | |
297 | break; | |
298 | ||
299 | case ACPI_STATE_C3: | |
300 | /* Disable bus master arbitration */ | |
301 | acpi_set_register(ACPI_BITREG_ARB_DISABLE, 1, ACPI_MTX_DO_NOT_LOCK); | |
302 | /* Get start time (ticks) */ | |
303 | t1 = inl(acpi_fadt.xpm_tmr_blk.address); | |
304 | /* Invoke C3 */ | |
305 | inb(cx->address); | |
306 | /* Dummy op - must do something useless after P_LVL3 read */ | |
307 | t2 = inl(acpi_fadt.xpm_tmr_blk.address); | |
308 | /* Get end time (ticks) */ | |
309 | t2 = inl(acpi_fadt.xpm_tmr_blk.address); | |
310 | /* Enable bus master arbitration */ | |
311 | acpi_set_register(ACPI_BITREG_ARB_DISABLE, 0, ACPI_MTX_DO_NOT_LOCK); | |
312 | /* Re-enable interrupts */ | |
313 | local_irq_enable(); | |
314 | /* Compute time (ticks) that we were actually asleep */ | |
315 | sleep_ticks = ticks_elapsed(t1, t2) - cx->latency_ticks - C3_OVERHEAD; | |
316 | break; | |
317 | ||
318 | default: | |
319 | local_irq_enable(); | |
320 | return; | |
321 | } | |
322 | ||
323 | next_state = pr->power.state; | |
324 | ||
325 | /* | |
326 | * Promotion? | |
327 | * ---------- | |
328 | * Track the number of longs (time asleep is greater than threshold) | |
329 | * and promote when the count threshold is reached. Note that bus | |
330 | * mastering activity may prevent promotions. | |
331 | * Do not promote above max_cstate. | |
332 | */ | |
333 | if (cx->promotion.state && | |
334 | ((cx->promotion.state - pr->power.states) <= max_cstate)) { | |
335 | if (sleep_ticks > cx->promotion.threshold.ticks) { | |
336 | cx->promotion.count++; | |
337 | cx->demotion.count = 0; | |
338 | if (cx->promotion.count >= cx->promotion.threshold.count) { | |
339 | if (pr->flags.bm_check) { | |
340 | if (!(pr->power.bm_activity & cx->promotion.threshold.bm)) { | |
341 | next_state = cx->promotion.state; | |
342 | goto end; | |
343 | } | |
344 | } | |
345 | else { | |
346 | next_state = cx->promotion.state; | |
347 | goto end; | |
348 | } | |
349 | } | |
350 | } | |
351 | } | |
352 | ||
353 | /* | |
354 | * Demotion? | |
355 | * --------- | |
356 | * Track the number of shorts (time asleep is less than time threshold) | |
357 | * and demote when the usage threshold is reached. | |
358 | */ | |
359 | if (cx->demotion.state) { | |
360 | if (sleep_ticks < cx->demotion.threshold.ticks) { | |
361 | cx->demotion.count++; | |
362 | cx->promotion.count = 0; | |
363 | if (cx->demotion.count >= cx->demotion.threshold.count) { | |
364 | next_state = cx->demotion.state; | |
365 | goto end; | |
366 | } | |
367 | } | |
368 | } | |
369 | ||
370 | end: | |
371 | /* | |
372 | * Demote if current state exceeds max_cstate | |
373 | */ | |
374 | if ((pr->power.state - pr->power.states) > max_cstate) { | |
375 | if (cx->demotion.state) | |
376 | next_state = cx->demotion.state; | |
377 | } | |
378 | ||
379 | /* | |
380 | * New Cx State? | |
381 | * ------------- | |
382 | * If we're going to start using a new Cx state we must clean up | |
383 | * from the previous and prepare to use the new. | |
384 | */ | |
385 | if (next_state != pr->power.state) | |
386 | acpi_processor_power_activate(pr, next_state); | |
387 | ||
388 | return; | |
389 | ||
390 | easy_out: | |
391 | /* do C1 instead of busy loop */ | |
392 | if (pm_idle_save) | |
393 | pm_idle_save(); | |
394 | else | |
395 | safe_halt(); | |
396 | return; | |
397 | } | |
398 | ||
399 | ||
400 | static int | |
401 | acpi_processor_set_power_policy ( | |
402 | struct acpi_processor *pr) | |
403 | { | |
404 | unsigned int i; | |
405 | unsigned int state_is_set = 0; | |
406 | struct acpi_processor_cx *lower = NULL; | |
407 | struct acpi_processor_cx *higher = NULL; | |
408 | struct acpi_processor_cx *cx; | |
409 | ||
410 | ACPI_FUNCTION_TRACE("acpi_processor_set_power_policy"); | |
411 | ||
412 | if (!pr) | |
413 | return_VALUE(-EINVAL); | |
414 | ||
415 | /* | |
416 | * This function sets the default Cx state policy (OS idle handler). | |
417 | * Our scheme is to promote quickly to C2 but more conservatively | |
418 | * to C3. We're favoring C2 for its characteristics of low latency | |
419 | * (quick response), good power savings, and ability to allow bus | |
420 | * mastering activity. Note that the Cx state policy is completely | |
421 | * customizable and can be altered dynamically. | |
422 | */ | |
423 | ||
424 | /* startup state */ | |
425 | for (i=1; i < ACPI_PROCESSOR_MAX_POWER; i++) { | |
426 | cx = &pr->power.states[i]; | |
427 | if (!cx->valid) | |
428 | continue; | |
429 | ||
430 | if (!state_is_set) | |
431 | pr->power.state = cx; | |
432 | state_is_set++; | |
433 | break; | |
434 | } | |
435 | ||
436 | if (!state_is_set) | |
437 | return_VALUE(-ENODEV); | |
438 | ||
439 | /* demotion */ | |
440 | for (i=1; i < ACPI_PROCESSOR_MAX_POWER; i++) { | |
441 | cx = &pr->power.states[i]; | |
442 | if (!cx->valid) | |
443 | continue; | |
444 | ||
445 | if (lower) { | |
446 | cx->demotion.state = lower; | |
447 | cx->demotion.threshold.ticks = cx->latency_ticks; | |
448 | cx->demotion.threshold.count = 1; | |
449 | if (cx->type == ACPI_STATE_C3) | |
450 | cx->demotion.threshold.bm = bm_history; | |
451 | } | |
452 | ||
453 | lower = cx; | |
454 | } | |
455 | ||
456 | /* promotion */ | |
457 | for (i = (ACPI_PROCESSOR_MAX_POWER - 1); i > 0; i--) { | |
458 | cx = &pr->power.states[i]; | |
459 | if (!cx->valid) | |
460 | continue; | |
461 | ||
462 | if (higher) { | |
463 | cx->promotion.state = higher; | |
464 | cx->promotion.threshold.ticks = cx->latency_ticks; | |
465 | if (cx->type >= ACPI_STATE_C2) | |
466 | cx->promotion.threshold.count = 4; | |
467 | else | |
468 | cx->promotion.threshold.count = 10; | |
469 | if (higher->type == ACPI_STATE_C3) | |
470 | cx->promotion.threshold.bm = bm_history; | |
471 | } | |
472 | ||
473 | higher = cx; | |
474 | } | |
475 | ||
476 | return_VALUE(0); | |
477 | } | |
478 | ||
479 | ||
480 | static int acpi_processor_get_power_info_fadt (struct acpi_processor *pr) | |
481 | { | |
482 | int i; | |
483 | ||
484 | ACPI_FUNCTION_TRACE("acpi_processor_get_power_info_fadt"); | |
485 | ||
486 | if (!pr) | |
487 | return_VALUE(-EINVAL); | |
488 | ||
489 | if (!pr->pblk) | |
490 | return_VALUE(-ENODEV); | |
491 | ||
492 | for (i = 0; i < ACPI_PROCESSOR_MAX_POWER; i++) | |
493 | memset(pr->power.states, 0, sizeof(struct acpi_processor_cx)); | |
494 | ||
495 | /* if info is obtained from pblk/fadt, type equals state */ | |
496 | pr->power.states[ACPI_STATE_C1].type = ACPI_STATE_C1; | |
497 | pr->power.states[ACPI_STATE_C2].type = ACPI_STATE_C2; | |
498 | pr->power.states[ACPI_STATE_C3].type = ACPI_STATE_C3; | |
499 | ||
500 | /* the C0 state only exists as a filler in our array, | |
501 | * and all processors need to support C1 */ | |
502 | pr->power.states[ACPI_STATE_C0].valid = 1; | |
503 | pr->power.states[ACPI_STATE_C1].valid = 1; | |
504 | ||
505 | /* determine C2 and C3 address from pblk */ | |
506 | pr->power.states[ACPI_STATE_C2].address = pr->pblk + 4; | |
507 | pr->power.states[ACPI_STATE_C3].address = pr->pblk + 5; | |
508 | ||
509 | /* determine latencies from FADT */ | |
510 | pr->power.states[ACPI_STATE_C2].latency = acpi_fadt.plvl2_lat; | |
511 | pr->power.states[ACPI_STATE_C3].latency = acpi_fadt.plvl3_lat; | |
512 | ||
513 | ACPI_DEBUG_PRINT((ACPI_DB_INFO, | |
514 | "lvl2[0x%08x] lvl3[0x%08x]\n", | |
515 | pr->power.states[ACPI_STATE_C2].address, | |
516 | pr->power.states[ACPI_STATE_C3].address)); | |
517 | ||
518 | return_VALUE(0); | |
519 | } | |
520 | ||
521 | ||
522 | static int acpi_processor_get_power_info_cst (struct acpi_processor *pr) | |
523 | { | |
524 | acpi_status status = 0; | |
525 | acpi_integer count; | |
526 | int i; | |
527 | struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL}; | |
528 | union acpi_object *cst; | |
529 | ||
530 | ACPI_FUNCTION_TRACE("acpi_processor_get_power_info_cst"); | |
531 | ||
532 | if (errata.smp) | |
533 | return_VALUE(-ENODEV); | |
534 | ||
535 | if (nocst) | |
536 | return_VALUE(-ENODEV); | |
537 | ||
538 | pr->power.count = 0; | |
539 | for (i = 0; i < ACPI_PROCESSOR_MAX_POWER; i++) | |
540 | memset(pr->power.states, 0, sizeof(struct acpi_processor_cx)); | |
541 | ||
542 | status = acpi_evaluate_object(pr->handle, "_CST", NULL, &buffer); | |
543 | if (ACPI_FAILURE(status)) { | |
544 | ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No _CST, giving up\n")); | |
545 | return_VALUE(-ENODEV); | |
546 | } | |
547 | ||
548 | cst = (union acpi_object *) buffer.pointer; | |
549 | ||
550 | /* There must be at least 2 elements */ | |
551 | if (!cst || (cst->type != ACPI_TYPE_PACKAGE) || cst->package.count < 2) { | |
552 | ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "not enough elements in _CST\n")); | |
553 | status = -EFAULT; | |
554 | goto end; | |
555 | } | |
556 | ||
557 | count = cst->package.elements[0].integer.value; | |
558 | ||
559 | /* Validate number of power states. */ | |
560 | if (count < 1 || count != cst->package.count - 1) { | |
561 | ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "count given by _CST is not valid\n")); | |
562 | status = -EFAULT; | |
563 | goto end; | |
564 | } | |
565 | ||
566 | /* We support up to ACPI_PROCESSOR_MAX_POWER. */ | |
567 | if (count > ACPI_PROCESSOR_MAX_POWER) { | |
568 | printk(KERN_WARNING "Limiting number of power states to max (%d)\n", ACPI_PROCESSOR_MAX_POWER); | |
569 | printk(KERN_WARNING "Please increase ACPI_PROCESSOR_MAX_POWER if needed.\n"); | |
570 | count = ACPI_PROCESSOR_MAX_POWER; | |
571 | } | |
572 | ||
573 | /* Tell driver that at least _CST is supported. */ | |
574 | pr->flags.has_cst = 1; | |
575 | ||
576 | for (i = 1; i <= count; i++) { | |
577 | union acpi_object *element; | |
578 | union acpi_object *obj; | |
579 | struct acpi_power_register *reg; | |
580 | struct acpi_processor_cx cx; | |
581 | ||
582 | memset(&cx, 0, sizeof(cx)); | |
583 | ||
584 | element = (union acpi_object *) &(cst->package.elements[i]); | |
585 | if (element->type != ACPI_TYPE_PACKAGE) | |
586 | continue; | |
587 | ||
588 | if (element->package.count != 4) | |
589 | continue; | |
590 | ||
591 | obj = (union acpi_object *) &(element->package.elements[0]); | |
592 | ||
593 | if (obj->type != ACPI_TYPE_BUFFER) | |
594 | continue; | |
595 | ||
596 | reg = (struct acpi_power_register *) obj->buffer.pointer; | |
597 | ||
598 | if (reg->space_id != ACPI_ADR_SPACE_SYSTEM_IO && | |
599 | (reg->space_id != ACPI_ADR_SPACE_FIXED_HARDWARE)) | |
600 | continue; | |
601 | ||
602 | cx.address = (reg->space_id == ACPI_ADR_SPACE_FIXED_HARDWARE) ? | |
603 | 0 : reg->address; | |
604 | ||
605 | /* There should be an easy way to extract an integer... */ | |
606 | obj = (union acpi_object *) &(element->package.elements[1]); | |
607 | if (obj->type != ACPI_TYPE_INTEGER) | |
608 | continue; | |
609 | ||
610 | cx.type = obj->integer.value; | |
611 | ||
612 | if ((cx.type != ACPI_STATE_C1) && | |
613 | (reg->space_id != ACPI_ADR_SPACE_SYSTEM_IO)) | |
614 | continue; | |
615 | ||
616 | if ((cx.type < ACPI_STATE_C1) || | |
617 | (cx.type > ACPI_STATE_C3)) | |
618 | continue; | |
619 | ||
620 | obj = (union acpi_object *) &(element->package.elements[2]); | |
621 | if (obj->type != ACPI_TYPE_INTEGER) | |
622 | continue; | |
623 | ||
624 | cx.latency = obj->integer.value; | |
625 | ||
626 | obj = (union acpi_object *) &(element->package.elements[3]); | |
627 | if (obj->type != ACPI_TYPE_INTEGER) | |
628 | continue; | |
629 | ||
630 | cx.power = obj->integer.value; | |
631 | ||
632 | (pr->power.count)++; | |
633 | memcpy(&(pr->power.states[pr->power.count]), &cx, sizeof(cx)); | |
634 | } | |
635 | ||
636 | ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d power states\n", pr->power.count)); | |
637 | ||
638 | /* Validate number of power states discovered */ | |
639 | if (pr->power.count < 2) | |
640 | status = -ENODEV; | |
641 | ||
642 | end: | |
643 | acpi_os_free(buffer.pointer); | |
644 | ||
645 | return_VALUE(status); | |
646 | } | |
647 | ||
648 | ||
649 | static void acpi_processor_power_verify_c2(struct acpi_processor_cx *cx) | |
650 | { | |
651 | ACPI_FUNCTION_TRACE("acpi_processor_get_power_verify_c2"); | |
652 | ||
653 | if (!cx->address) | |
654 | return_VOID; | |
655 | ||
656 | /* | |
657 | * C2 latency must be less than or equal to 100 | |
658 | * microseconds. | |
659 | */ | |
660 | else if (cx->latency > ACPI_PROCESSOR_MAX_C2_LATENCY) { | |
661 | ACPI_DEBUG_PRINT((ACPI_DB_INFO, | |
662 | "latency too large [%d]\n", | |
663 | cx->latency)); | |
664 | return_VOID; | |
665 | } | |
666 | ||
667 | /* We're (currently) only supporting C2 on UP */ | |
668 | else if (errata.smp) { | |
669 | ACPI_DEBUG_PRINT((ACPI_DB_INFO, | |
670 | "C2 not supported in SMP mode\n")); | |
671 | return_VOID; | |
672 | } | |
673 | ||
674 | /* | |
675 | * Otherwise we've met all of our C2 requirements. | |
676 | * Normalize the C2 latency to expidite policy | |
677 | */ | |
678 | cx->valid = 1; | |
679 | cx->latency_ticks = US_TO_PM_TIMER_TICKS(cx->latency); | |
680 | ||
681 | return_VOID; | |
682 | } | |
683 | ||
684 | ||
685 | static void acpi_processor_power_verify_c3( | |
686 | struct acpi_processor *pr, | |
687 | struct acpi_processor_cx *cx) | |
688 | { | |
689 | ACPI_FUNCTION_TRACE("acpi_processor_get_power_verify_c3"); | |
690 | ||
691 | if (!cx->address) | |
692 | return_VOID; | |
693 | ||
694 | /* | |
695 | * C3 latency must be less than or equal to 1000 | |
696 | * microseconds. | |
697 | */ | |
698 | else if (cx->latency > ACPI_PROCESSOR_MAX_C3_LATENCY) { | |
699 | ACPI_DEBUG_PRINT((ACPI_DB_INFO, | |
700 | "latency too large [%d]\n", | |
701 | cx->latency)); | |
702 | return_VOID; | |
703 | } | |
704 | ||
705 | /* bus mastering control is necessary */ | |
706 | else if (!pr->flags.bm_control) { | |
707 | ACPI_DEBUG_PRINT((ACPI_DB_INFO, | |
708 | "C3 support requires bus mastering control\n")); | |
709 | return_VOID; | |
710 | } | |
711 | ||
712 | /* We're (currently) only supporting C2 on UP */ | |
713 | else if (errata.smp) { | |
714 | ACPI_DEBUG_PRINT((ACPI_DB_INFO, | |
715 | "C3 not supported in SMP mode\n")); | |
716 | return_VOID; | |
717 | } | |
718 | ||
719 | /* | |
720 | * PIIX4 Erratum #18: We don't support C3 when Type-F (fast) | |
721 | * DMA transfers are used by any ISA device to avoid livelock. | |
722 | * Note that we could disable Type-F DMA (as recommended by | |
723 | * the erratum), but this is known to disrupt certain ISA | |
724 | * devices thus we take the conservative approach. | |
725 | */ | |
726 | else if (errata.piix4.fdma) { | |
727 | ACPI_DEBUG_PRINT((ACPI_DB_INFO, | |
728 | "C3 not supported on PIIX4 with Type-F DMA\n")); | |
729 | return_VOID; | |
730 | } | |
731 | ||
732 | /* | |
733 | * Otherwise we've met all of our C3 requirements. | |
734 | * Normalize the C3 latency to expidite policy. Enable | |
735 | * checking of bus mastering status (bm_check) so we can | |
736 | * use this in our C3 policy | |
737 | */ | |
738 | cx->valid = 1; | |
739 | cx->latency_ticks = US_TO_PM_TIMER_TICKS(cx->latency); | |
740 | pr->flags.bm_check = 1; | |
741 | ||
742 | return_VOID; | |
743 | } | |
744 | ||
745 | ||
746 | static int acpi_processor_power_verify(struct acpi_processor *pr) | |
747 | { | |
748 | unsigned int i; | |
749 | unsigned int working = 0; | |
750 | ||
751 | for (i=1; i < ACPI_PROCESSOR_MAX_POWER; i++) { | |
752 | struct acpi_processor_cx *cx = &pr->power.states[i]; | |
753 | ||
754 | switch (cx->type) { | |
755 | case ACPI_STATE_C1: | |
756 | cx->valid = 1; | |
757 | break; | |
758 | ||
759 | case ACPI_STATE_C2: | |
760 | acpi_processor_power_verify_c2(cx); | |
761 | break; | |
762 | ||
763 | case ACPI_STATE_C3: | |
764 | acpi_processor_power_verify_c3(pr, cx); | |
765 | break; | |
766 | } | |
767 | ||
768 | if (cx->valid) | |
769 | working++; | |
770 | } | |
771 | ||
772 | return (working); | |
773 | } | |
774 | ||
775 | static int acpi_processor_get_power_info ( | |
776 | struct acpi_processor *pr) | |
777 | { | |
778 | unsigned int i; | |
779 | int result; | |
780 | ||
781 | ACPI_FUNCTION_TRACE("acpi_processor_get_power_info"); | |
782 | ||
783 | /* NOTE: the idle thread may not be running while calling | |
784 | * this function */ | |
785 | ||
786 | result = acpi_processor_get_power_info_cst(pr); | |
787 | if ((result) || (acpi_processor_power_verify(pr) < 2)) { | |
788 | result = acpi_processor_get_power_info_fadt(pr); | |
789 | if (result) | |
790 | return_VALUE(result); | |
791 | ||
792 | if (acpi_processor_power_verify(pr) < 2) | |
793 | return_VALUE(-ENODEV); | |
794 | } | |
795 | ||
796 | /* | |
797 | * Set Default Policy | |
798 | * ------------------ | |
799 | * Now that we know which states are supported, set the default | |
800 | * policy. Note that this policy can be changed dynamically | |
801 | * (e.g. encourage deeper sleeps to conserve battery life when | |
802 | * not on AC). | |
803 | */ | |
804 | result = acpi_processor_set_power_policy(pr); | |
805 | if (result) | |
806 | return_VALUE(result); | |
807 | ||
808 | /* | |
809 | * if one state of type C2 or C3 is available, mark this | |
810 | * CPU as being "idle manageable" | |
811 | */ | |
812 | for (i = 1; i < ACPI_PROCESSOR_MAX_POWER; i++) { | |
813 | if (pr->power.states[i].valid) | |
814 | pr->power.count = i; | |
815 | if ((pr->power.states[i].valid) && | |
816 | (pr->power.states[i].type >= ACPI_STATE_C2)) | |
817 | pr->flags.power = 1; | |
818 | } | |
819 | ||
820 | return_VALUE(0); | |
821 | } | |
822 | ||
823 | int acpi_processor_cst_has_changed (struct acpi_processor *pr) | |
824 | { | |
825 | int result = 0; | |
826 | ||
827 | ACPI_FUNCTION_TRACE("acpi_processor_cst_has_changed"); | |
828 | ||
829 | if (!pr) | |
830 | return_VALUE(-EINVAL); | |
831 | ||
832 | if (errata.smp || nocst) { | |
833 | return_VALUE(-ENODEV); | |
834 | } | |
835 | ||
836 | if (!pr->flags.power_setup_done) | |
837 | return_VALUE(-ENODEV); | |
838 | ||
839 | /* Fall back to the default idle loop */ | |
840 | pm_idle = pm_idle_save; | |
fbd568a3 | 841 | synchronize_sched(); /* Relies on interrupts forcing exit from idle. */ |
1da177e4 LT |
842 | |
843 | pr->flags.power = 0; | |
844 | result = acpi_processor_get_power_info(pr); | |
845 | if ((pr->flags.power == 1) && (pr->flags.power_setup_done)) | |
846 | pm_idle = acpi_processor_idle; | |
847 | ||
848 | return_VALUE(result); | |
849 | } | |
850 | ||
851 | /* proc interface */ | |
852 | ||
853 | static int acpi_processor_power_seq_show(struct seq_file *seq, void *offset) | |
854 | { | |
855 | struct acpi_processor *pr = (struct acpi_processor *)seq->private; | |
856 | unsigned int i; | |
857 | ||
858 | ACPI_FUNCTION_TRACE("acpi_processor_power_seq_show"); | |
859 | ||
860 | if (!pr) | |
861 | goto end; | |
862 | ||
863 | seq_printf(seq, "active state: C%zd\n" | |
864 | "max_cstate: C%d\n" | |
865 | "bus master activity: %08x\n", | |
866 | pr->power.state ? pr->power.state - pr->power.states : 0, | |
867 | max_cstate, | |
868 | (unsigned)pr->power.bm_activity); | |
869 | ||
870 | seq_puts(seq, "states:\n"); | |
871 | ||
872 | for (i = 1; i <= pr->power.count; i++) { | |
873 | seq_printf(seq, " %cC%d: ", | |
874 | (&pr->power.states[i] == pr->power.state?'*':' '), i); | |
875 | ||
876 | if (!pr->power.states[i].valid) { | |
877 | seq_puts(seq, "<not supported>\n"); | |
878 | continue; | |
879 | } | |
880 | ||
881 | switch (pr->power.states[i].type) { | |
882 | case ACPI_STATE_C1: | |
883 | seq_printf(seq, "type[C1] "); | |
884 | break; | |
885 | case ACPI_STATE_C2: | |
886 | seq_printf(seq, "type[C2] "); | |
887 | break; | |
888 | case ACPI_STATE_C3: | |
889 | seq_printf(seq, "type[C3] "); | |
890 | break; | |
891 | default: | |
892 | seq_printf(seq, "type[--] "); | |
893 | break; | |
894 | } | |
895 | ||
896 | if (pr->power.states[i].promotion.state) | |
897 | seq_printf(seq, "promotion[C%zd] ", | |
898 | (pr->power.states[i].promotion.state - | |
899 | pr->power.states)); | |
900 | else | |
901 | seq_puts(seq, "promotion[--] "); | |
902 | ||
903 | if (pr->power.states[i].demotion.state) | |
904 | seq_printf(seq, "demotion[C%zd] ", | |
905 | (pr->power.states[i].demotion.state - | |
906 | pr->power.states)); | |
907 | else | |
908 | seq_puts(seq, "demotion[--] "); | |
909 | ||
910 | seq_printf(seq, "latency[%03d] usage[%08d]\n", | |
911 | pr->power.states[i].latency, | |
912 | pr->power.states[i].usage); | |
913 | } | |
914 | ||
915 | end: | |
916 | return_VALUE(0); | |
917 | } | |
918 | ||
919 | static int acpi_processor_power_open_fs(struct inode *inode, struct file *file) | |
920 | { | |
921 | return single_open(file, acpi_processor_power_seq_show, | |
922 | PDE(inode)->data); | |
923 | } | |
924 | ||
925 | static struct file_operations acpi_processor_power_fops = { | |
926 | .open = acpi_processor_power_open_fs, | |
927 | .read = seq_read, | |
928 | .llseek = seq_lseek, | |
929 | .release = single_release, | |
930 | }; | |
931 | ||
932 | ||
933 | int acpi_processor_power_init(struct acpi_processor *pr, struct acpi_device *device) | |
934 | { | |
935 | acpi_status status = 0; | |
936 | static int first_run = 0; | |
937 | struct proc_dir_entry *entry = NULL; | |
938 | unsigned int i; | |
939 | ||
940 | ACPI_FUNCTION_TRACE("acpi_processor_power_init"); | |
941 | ||
942 | if (!first_run) { | |
943 | dmi_check_system(processor_power_dmi_table); | |
944 | if (max_cstate < ACPI_C_STATES_MAX) | |
945 | printk(KERN_NOTICE "ACPI: processor limited to max C-state %d\n", max_cstate); | |
946 | first_run++; | |
947 | } | |
948 | ||
949 | if (!errata.smp && (pr->id == 0) && acpi_fadt.cst_cnt && !nocst) { | |
950 | status = acpi_os_write_port(acpi_fadt.smi_cmd, acpi_fadt.cst_cnt, 8); | |
951 | if (ACPI_FAILURE(status)) { | |
952 | ACPI_DEBUG_PRINT((ACPI_DB_ERROR, | |
953 | "Notifying BIOS of _CST ability failed\n")); | |
954 | } | |
955 | } | |
956 | ||
957 | acpi_processor_get_power_info(pr); | |
958 | ||
959 | /* | |
960 | * Install the idle handler if processor power management is supported. | |
961 | * Note that we use previously set idle handler will be used on | |
962 | * platforms that only support C1. | |
963 | */ | |
964 | if ((pr->flags.power) && (!boot_option_idle_override)) { | |
965 | printk(KERN_INFO PREFIX "CPU%d (power states:", pr->id); | |
966 | for (i = 1; i <= pr->power.count; i++) | |
967 | if (pr->power.states[i].valid) | |
968 | printk(" C%d[C%d]", i, pr->power.states[i].type); | |
969 | printk(")\n"); | |
970 | ||
971 | if (pr->id == 0) { | |
972 | pm_idle_save = pm_idle; | |
973 | pm_idle = acpi_processor_idle; | |
974 | } | |
975 | } | |
976 | ||
977 | /* 'power' [R] */ | |
978 | entry = create_proc_entry(ACPI_PROCESSOR_FILE_POWER, | |
979 | S_IRUGO, acpi_device_dir(device)); | |
980 | if (!entry) | |
981 | ACPI_DEBUG_PRINT((ACPI_DB_ERROR, | |
982 | "Unable to create '%s' fs entry\n", | |
983 | ACPI_PROCESSOR_FILE_POWER)); | |
984 | else { | |
985 | entry->proc_fops = &acpi_processor_power_fops; | |
986 | entry->data = acpi_driver_data(device); | |
987 | entry->owner = THIS_MODULE; | |
988 | } | |
989 | ||
990 | pr->flags.power_setup_done = 1; | |
991 | ||
992 | return_VALUE(0); | |
993 | } | |
994 | ||
995 | int acpi_processor_power_exit(struct acpi_processor *pr, struct acpi_device *device) | |
996 | { | |
997 | ACPI_FUNCTION_TRACE("acpi_processor_power_exit"); | |
998 | ||
999 | pr->flags.power_setup_done = 0; | |
1000 | ||
1001 | if (acpi_device_dir(device)) | |
1002 | remove_proc_entry(ACPI_PROCESSOR_FILE_POWER,acpi_device_dir(device)); | |
1003 | ||
1004 | /* Unregister the idle handler when processor #0 is removed. */ | |
1005 | if (pr->id == 0) { | |
1006 | pm_idle = pm_idle_save; | |
1007 | ||
1008 | /* | |
1009 | * We are about to unload the current idle thread pm callback | |
1010 | * (pm_idle), Wait for all processors to update cached/local | |
1011 | * copies of pm_idle before proceeding. | |
1012 | */ | |
1013 | cpu_idle_wait(); | |
1014 | } | |
1015 | ||
1016 | return_VALUE(0); | |
1017 | } |