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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 | ||
acf05f4b VP |
522 | static int acpi_processor_get_power_info_default_c1 (struct acpi_processor *pr) |
523 | { | |
524 | int i; | |
525 | ||
526 | ACPI_FUNCTION_TRACE("acpi_processor_get_power_info_default_c1"); | |
527 | ||
528 | for (i = 0; i < ACPI_PROCESSOR_MAX_POWER; i++) | |
529 | memset(pr->power.states, 0, sizeof(struct acpi_processor_cx)); | |
530 | ||
531 | /* if info is obtained from pblk/fadt, type equals state */ | |
532 | pr->power.states[ACPI_STATE_C1].type = ACPI_STATE_C1; | |
533 | pr->power.states[ACPI_STATE_C2].type = ACPI_STATE_C2; | |
534 | pr->power.states[ACPI_STATE_C3].type = ACPI_STATE_C3; | |
535 | ||
536 | /* the C0 state only exists as a filler in our array, | |
537 | * and all processors need to support C1 */ | |
538 | pr->power.states[ACPI_STATE_C0].valid = 1; | |
539 | pr->power.states[ACPI_STATE_C1].valid = 1; | |
540 | ||
541 | return_VALUE(0); | |
542 | } | |
543 | ||
544 | ||
1da177e4 LT |
545 | static int acpi_processor_get_power_info_cst (struct acpi_processor *pr) |
546 | { | |
547 | acpi_status status = 0; | |
548 | acpi_integer count; | |
549 | int i; | |
550 | struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL}; | |
551 | union acpi_object *cst; | |
552 | ||
553 | ACPI_FUNCTION_TRACE("acpi_processor_get_power_info_cst"); | |
554 | ||
555 | if (errata.smp) | |
556 | return_VALUE(-ENODEV); | |
557 | ||
558 | if (nocst) | |
559 | return_VALUE(-ENODEV); | |
560 | ||
561 | pr->power.count = 0; | |
562 | for (i = 0; i < ACPI_PROCESSOR_MAX_POWER; i++) | |
563 | memset(pr->power.states, 0, sizeof(struct acpi_processor_cx)); | |
564 | ||
565 | status = acpi_evaluate_object(pr->handle, "_CST", NULL, &buffer); | |
566 | if (ACPI_FAILURE(status)) { | |
567 | ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No _CST, giving up\n")); | |
568 | return_VALUE(-ENODEV); | |
569 | } | |
570 | ||
571 | cst = (union acpi_object *) buffer.pointer; | |
572 | ||
573 | /* There must be at least 2 elements */ | |
574 | if (!cst || (cst->type != ACPI_TYPE_PACKAGE) || cst->package.count < 2) { | |
575 | ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "not enough elements in _CST\n")); | |
576 | status = -EFAULT; | |
577 | goto end; | |
578 | } | |
579 | ||
580 | count = cst->package.elements[0].integer.value; | |
581 | ||
582 | /* Validate number of power states. */ | |
583 | if (count < 1 || count != cst->package.count - 1) { | |
584 | ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "count given by _CST is not valid\n")); | |
585 | status = -EFAULT; | |
586 | goto end; | |
587 | } | |
588 | ||
589 | /* We support up to ACPI_PROCESSOR_MAX_POWER. */ | |
590 | if (count > ACPI_PROCESSOR_MAX_POWER) { | |
591 | printk(KERN_WARNING "Limiting number of power states to max (%d)\n", ACPI_PROCESSOR_MAX_POWER); | |
592 | printk(KERN_WARNING "Please increase ACPI_PROCESSOR_MAX_POWER if needed.\n"); | |
593 | count = ACPI_PROCESSOR_MAX_POWER; | |
594 | } | |
595 | ||
596 | /* Tell driver that at least _CST is supported. */ | |
597 | pr->flags.has_cst = 1; | |
598 | ||
599 | for (i = 1; i <= count; i++) { | |
600 | union acpi_object *element; | |
601 | union acpi_object *obj; | |
602 | struct acpi_power_register *reg; | |
603 | struct acpi_processor_cx cx; | |
604 | ||
605 | memset(&cx, 0, sizeof(cx)); | |
606 | ||
607 | element = (union acpi_object *) &(cst->package.elements[i]); | |
608 | if (element->type != ACPI_TYPE_PACKAGE) | |
609 | continue; | |
610 | ||
611 | if (element->package.count != 4) | |
612 | continue; | |
613 | ||
614 | obj = (union acpi_object *) &(element->package.elements[0]); | |
615 | ||
616 | if (obj->type != ACPI_TYPE_BUFFER) | |
617 | continue; | |
618 | ||
619 | reg = (struct acpi_power_register *) obj->buffer.pointer; | |
620 | ||
621 | if (reg->space_id != ACPI_ADR_SPACE_SYSTEM_IO && | |
622 | (reg->space_id != ACPI_ADR_SPACE_FIXED_HARDWARE)) | |
623 | continue; | |
624 | ||
625 | cx.address = (reg->space_id == ACPI_ADR_SPACE_FIXED_HARDWARE) ? | |
626 | 0 : reg->address; | |
627 | ||
628 | /* There should be an easy way to extract an integer... */ | |
629 | obj = (union acpi_object *) &(element->package.elements[1]); | |
630 | if (obj->type != ACPI_TYPE_INTEGER) | |
631 | continue; | |
632 | ||
633 | cx.type = obj->integer.value; | |
634 | ||
635 | if ((cx.type != ACPI_STATE_C1) && | |
636 | (reg->space_id != ACPI_ADR_SPACE_SYSTEM_IO)) | |
637 | continue; | |
638 | ||
639 | if ((cx.type < ACPI_STATE_C1) || | |
640 | (cx.type > ACPI_STATE_C3)) | |
641 | continue; | |
642 | ||
643 | obj = (union acpi_object *) &(element->package.elements[2]); | |
644 | if (obj->type != ACPI_TYPE_INTEGER) | |
645 | continue; | |
646 | ||
647 | cx.latency = obj->integer.value; | |
648 | ||
649 | obj = (union acpi_object *) &(element->package.elements[3]); | |
650 | if (obj->type != ACPI_TYPE_INTEGER) | |
651 | continue; | |
652 | ||
653 | cx.power = obj->integer.value; | |
654 | ||
655 | (pr->power.count)++; | |
656 | memcpy(&(pr->power.states[pr->power.count]), &cx, sizeof(cx)); | |
657 | } | |
658 | ||
659 | ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d power states\n", pr->power.count)); | |
660 | ||
661 | /* Validate number of power states discovered */ | |
662 | if (pr->power.count < 2) | |
663 | status = -ENODEV; | |
664 | ||
665 | end: | |
666 | acpi_os_free(buffer.pointer); | |
667 | ||
668 | return_VALUE(status); | |
669 | } | |
670 | ||
671 | ||
672 | static void acpi_processor_power_verify_c2(struct acpi_processor_cx *cx) | |
673 | { | |
674 | ACPI_FUNCTION_TRACE("acpi_processor_get_power_verify_c2"); | |
675 | ||
676 | if (!cx->address) | |
677 | return_VOID; | |
678 | ||
679 | /* | |
680 | * C2 latency must be less than or equal to 100 | |
681 | * microseconds. | |
682 | */ | |
683 | else if (cx->latency > ACPI_PROCESSOR_MAX_C2_LATENCY) { | |
684 | ACPI_DEBUG_PRINT((ACPI_DB_INFO, | |
685 | "latency too large [%d]\n", | |
686 | cx->latency)); | |
687 | return_VOID; | |
688 | } | |
689 | ||
690 | /* We're (currently) only supporting C2 on UP */ | |
691 | else if (errata.smp) { | |
692 | ACPI_DEBUG_PRINT((ACPI_DB_INFO, | |
693 | "C2 not supported in SMP mode\n")); | |
694 | return_VOID; | |
695 | } | |
696 | ||
697 | /* | |
698 | * Otherwise we've met all of our C2 requirements. | |
699 | * Normalize the C2 latency to expidite policy | |
700 | */ | |
701 | cx->valid = 1; | |
702 | cx->latency_ticks = US_TO_PM_TIMER_TICKS(cx->latency); | |
703 | ||
704 | return_VOID; | |
705 | } | |
706 | ||
707 | ||
708 | static void acpi_processor_power_verify_c3( | |
709 | struct acpi_processor *pr, | |
710 | struct acpi_processor_cx *cx) | |
711 | { | |
712 | ACPI_FUNCTION_TRACE("acpi_processor_get_power_verify_c3"); | |
713 | ||
714 | if (!cx->address) | |
715 | return_VOID; | |
716 | ||
717 | /* | |
718 | * C3 latency must be less than or equal to 1000 | |
719 | * microseconds. | |
720 | */ | |
721 | else if (cx->latency > ACPI_PROCESSOR_MAX_C3_LATENCY) { | |
722 | ACPI_DEBUG_PRINT((ACPI_DB_INFO, | |
723 | "latency too large [%d]\n", | |
724 | cx->latency)); | |
725 | return_VOID; | |
726 | } | |
727 | ||
728 | /* bus mastering control is necessary */ | |
729 | else if (!pr->flags.bm_control) { | |
730 | ACPI_DEBUG_PRINT((ACPI_DB_INFO, | |
731 | "C3 support requires bus mastering control\n")); | |
732 | return_VOID; | |
733 | } | |
734 | ||
735 | /* We're (currently) only supporting C2 on UP */ | |
736 | else if (errata.smp) { | |
737 | ACPI_DEBUG_PRINT((ACPI_DB_INFO, | |
738 | "C3 not supported in SMP mode\n")); | |
739 | return_VOID; | |
740 | } | |
741 | ||
742 | /* | |
743 | * PIIX4 Erratum #18: We don't support C3 when Type-F (fast) | |
744 | * DMA transfers are used by any ISA device to avoid livelock. | |
745 | * Note that we could disable Type-F DMA (as recommended by | |
746 | * the erratum), but this is known to disrupt certain ISA | |
747 | * devices thus we take the conservative approach. | |
748 | */ | |
749 | else if (errata.piix4.fdma) { | |
750 | ACPI_DEBUG_PRINT((ACPI_DB_INFO, | |
751 | "C3 not supported on PIIX4 with Type-F DMA\n")); | |
752 | return_VOID; | |
753 | } | |
754 | ||
755 | /* | |
756 | * Otherwise we've met all of our C3 requirements. | |
757 | * Normalize the C3 latency to expidite policy. Enable | |
758 | * checking of bus mastering status (bm_check) so we can | |
759 | * use this in our C3 policy | |
760 | */ | |
761 | cx->valid = 1; | |
762 | cx->latency_ticks = US_TO_PM_TIMER_TICKS(cx->latency); | |
763 | pr->flags.bm_check = 1; | |
764 | ||
765 | return_VOID; | |
766 | } | |
767 | ||
768 | ||
769 | static int acpi_processor_power_verify(struct acpi_processor *pr) | |
770 | { | |
771 | unsigned int i; | |
772 | unsigned int working = 0; | |
773 | ||
774 | for (i=1; i < ACPI_PROCESSOR_MAX_POWER; i++) { | |
775 | struct acpi_processor_cx *cx = &pr->power.states[i]; | |
776 | ||
777 | switch (cx->type) { | |
778 | case ACPI_STATE_C1: | |
779 | cx->valid = 1; | |
780 | break; | |
781 | ||
782 | case ACPI_STATE_C2: | |
783 | acpi_processor_power_verify_c2(cx); | |
784 | break; | |
785 | ||
786 | case ACPI_STATE_C3: | |
787 | acpi_processor_power_verify_c3(pr, cx); | |
788 | break; | |
789 | } | |
790 | ||
791 | if (cx->valid) | |
792 | working++; | |
793 | } | |
794 | ||
795 | return (working); | |
796 | } | |
797 | ||
798 | static int acpi_processor_get_power_info ( | |
799 | struct acpi_processor *pr) | |
800 | { | |
801 | unsigned int i; | |
802 | int result; | |
803 | ||
804 | ACPI_FUNCTION_TRACE("acpi_processor_get_power_info"); | |
805 | ||
806 | /* NOTE: the idle thread may not be running while calling | |
807 | * this function */ | |
808 | ||
809 | result = acpi_processor_get_power_info_cst(pr); | |
810 | if ((result) || (acpi_processor_power_verify(pr) < 2)) { | |
811 | result = acpi_processor_get_power_info_fadt(pr); | |
812 | if (result) | |
acf05f4b | 813 | result = acpi_processor_get_power_info_default_c1(pr); |
1da177e4 LT |
814 | } |
815 | ||
816 | /* | |
817 | * Set Default Policy | |
818 | * ------------------ | |
819 | * Now that we know which states are supported, set the default | |
820 | * policy. Note that this policy can be changed dynamically | |
821 | * (e.g. encourage deeper sleeps to conserve battery life when | |
822 | * not on AC). | |
823 | */ | |
824 | result = acpi_processor_set_power_policy(pr); | |
825 | if (result) | |
826 | return_VALUE(result); | |
827 | ||
828 | /* | |
829 | * if one state of type C2 or C3 is available, mark this | |
830 | * CPU as being "idle manageable" | |
831 | */ | |
832 | for (i = 1; i < ACPI_PROCESSOR_MAX_POWER; i++) { | |
acf05f4b | 833 | if (pr->power.states[i].valid) { |
1da177e4 | 834 | pr->power.count = i; |
1da177e4 | 835 | pr->flags.power = 1; |
acf05f4b | 836 | } |
1da177e4 LT |
837 | } |
838 | ||
839 | return_VALUE(0); | |
840 | } | |
841 | ||
842 | int acpi_processor_cst_has_changed (struct acpi_processor *pr) | |
843 | { | |
844 | int result = 0; | |
845 | ||
846 | ACPI_FUNCTION_TRACE("acpi_processor_cst_has_changed"); | |
847 | ||
848 | if (!pr) | |
849 | return_VALUE(-EINVAL); | |
850 | ||
851 | if (errata.smp || nocst) { | |
852 | return_VALUE(-ENODEV); | |
853 | } | |
854 | ||
855 | if (!pr->flags.power_setup_done) | |
856 | return_VALUE(-ENODEV); | |
857 | ||
858 | /* Fall back to the default idle loop */ | |
859 | pm_idle = pm_idle_save; | |
fbd568a3 | 860 | synchronize_sched(); /* Relies on interrupts forcing exit from idle. */ |
1da177e4 LT |
861 | |
862 | pr->flags.power = 0; | |
863 | result = acpi_processor_get_power_info(pr); | |
864 | if ((pr->flags.power == 1) && (pr->flags.power_setup_done)) | |
865 | pm_idle = acpi_processor_idle; | |
866 | ||
867 | return_VALUE(result); | |
868 | } | |
869 | ||
870 | /* proc interface */ | |
871 | ||
872 | static int acpi_processor_power_seq_show(struct seq_file *seq, void *offset) | |
873 | { | |
874 | struct acpi_processor *pr = (struct acpi_processor *)seq->private; | |
875 | unsigned int i; | |
876 | ||
877 | ACPI_FUNCTION_TRACE("acpi_processor_power_seq_show"); | |
878 | ||
879 | if (!pr) | |
880 | goto end; | |
881 | ||
882 | seq_printf(seq, "active state: C%zd\n" | |
883 | "max_cstate: C%d\n" | |
884 | "bus master activity: %08x\n", | |
885 | pr->power.state ? pr->power.state - pr->power.states : 0, | |
886 | max_cstate, | |
887 | (unsigned)pr->power.bm_activity); | |
888 | ||
889 | seq_puts(seq, "states:\n"); | |
890 | ||
891 | for (i = 1; i <= pr->power.count; i++) { | |
892 | seq_printf(seq, " %cC%d: ", | |
893 | (&pr->power.states[i] == pr->power.state?'*':' '), i); | |
894 | ||
895 | if (!pr->power.states[i].valid) { | |
896 | seq_puts(seq, "<not supported>\n"); | |
897 | continue; | |
898 | } | |
899 | ||
900 | switch (pr->power.states[i].type) { | |
901 | case ACPI_STATE_C1: | |
902 | seq_printf(seq, "type[C1] "); | |
903 | break; | |
904 | case ACPI_STATE_C2: | |
905 | seq_printf(seq, "type[C2] "); | |
906 | break; | |
907 | case ACPI_STATE_C3: | |
908 | seq_printf(seq, "type[C3] "); | |
909 | break; | |
910 | default: | |
911 | seq_printf(seq, "type[--] "); | |
912 | break; | |
913 | } | |
914 | ||
915 | if (pr->power.states[i].promotion.state) | |
916 | seq_printf(seq, "promotion[C%zd] ", | |
917 | (pr->power.states[i].promotion.state - | |
918 | pr->power.states)); | |
919 | else | |
920 | seq_puts(seq, "promotion[--] "); | |
921 | ||
922 | if (pr->power.states[i].demotion.state) | |
923 | seq_printf(seq, "demotion[C%zd] ", | |
924 | (pr->power.states[i].demotion.state - | |
925 | pr->power.states)); | |
926 | else | |
927 | seq_puts(seq, "demotion[--] "); | |
928 | ||
929 | seq_printf(seq, "latency[%03d] usage[%08d]\n", | |
930 | pr->power.states[i].latency, | |
931 | pr->power.states[i].usage); | |
932 | } | |
933 | ||
934 | end: | |
935 | return_VALUE(0); | |
936 | } | |
937 | ||
938 | static int acpi_processor_power_open_fs(struct inode *inode, struct file *file) | |
939 | { | |
940 | return single_open(file, acpi_processor_power_seq_show, | |
941 | PDE(inode)->data); | |
942 | } | |
943 | ||
944 | static struct file_operations acpi_processor_power_fops = { | |
945 | .open = acpi_processor_power_open_fs, | |
946 | .read = seq_read, | |
947 | .llseek = seq_lseek, | |
948 | .release = single_release, | |
949 | }; | |
950 | ||
951 | ||
952 | int acpi_processor_power_init(struct acpi_processor *pr, struct acpi_device *device) | |
953 | { | |
954 | acpi_status status = 0; | |
955 | static int first_run = 0; | |
956 | struct proc_dir_entry *entry = NULL; | |
957 | unsigned int i; | |
958 | ||
959 | ACPI_FUNCTION_TRACE("acpi_processor_power_init"); | |
960 | ||
961 | if (!first_run) { | |
962 | dmi_check_system(processor_power_dmi_table); | |
963 | if (max_cstate < ACPI_C_STATES_MAX) | |
964 | printk(KERN_NOTICE "ACPI: processor limited to max C-state %d\n", max_cstate); | |
965 | first_run++; | |
966 | } | |
967 | ||
968 | if (!errata.smp && (pr->id == 0) && acpi_fadt.cst_cnt && !nocst) { | |
969 | status = acpi_os_write_port(acpi_fadt.smi_cmd, acpi_fadt.cst_cnt, 8); | |
970 | if (ACPI_FAILURE(status)) { | |
971 | ACPI_DEBUG_PRINT((ACPI_DB_ERROR, | |
972 | "Notifying BIOS of _CST ability failed\n")); | |
973 | } | |
974 | } | |
975 | ||
976 | acpi_processor_get_power_info(pr); | |
977 | ||
978 | /* | |
979 | * Install the idle handler if processor power management is supported. | |
980 | * Note that we use previously set idle handler will be used on | |
981 | * platforms that only support C1. | |
982 | */ | |
983 | if ((pr->flags.power) && (!boot_option_idle_override)) { | |
984 | printk(KERN_INFO PREFIX "CPU%d (power states:", pr->id); | |
985 | for (i = 1; i <= pr->power.count; i++) | |
986 | if (pr->power.states[i].valid) | |
987 | printk(" C%d[C%d]", i, pr->power.states[i].type); | |
988 | printk(")\n"); | |
989 | ||
990 | if (pr->id == 0) { | |
991 | pm_idle_save = pm_idle; | |
992 | pm_idle = acpi_processor_idle; | |
993 | } | |
994 | } | |
995 | ||
996 | /* 'power' [R] */ | |
997 | entry = create_proc_entry(ACPI_PROCESSOR_FILE_POWER, | |
998 | S_IRUGO, acpi_device_dir(device)); | |
999 | if (!entry) | |
1000 | ACPI_DEBUG_PRINT((ACPI_DB_ERROR, | |
1001 | "Unable to create '%s' fs entry\n", | |
1002 | ACPI_PROCESSOR_FILE_POWER)); | |
1003 | else { | |
1004 | entry->proc_fops = &acpi_processor_power_fops; | |
1005 | entry->data = acpi_driver_data(device); | |
1006 | entry->owner = THIS_MODULE; | |
1007 | } | |
1008 | ||
1009 | pr->flags.power_setup_done = 1; | |
1010 | ||
1011 | return_VALUE(0); | |
1012 | } | |
1013 | ||
1014 | int acpi_processor_power_exit(struct acpi_processor *pr, struct acpi_device *device) | |
1015 | { | |
1016 | ACPI_FUNCTION_TRACE("acpi_processor_power_exit"); | |
1017 | ||
1018 | pr->flags.power_setup_done = 0; | |
1019 | ||
1020 | if (acpi_device_dir(device)) | |
1021 | remove_proc_entry(ACPI_PROCESSOR_FILE_POWER,acpi_device_dir(device)); | |
1022 | ||
1023 | /* Unregister the idle handler when processor #0 is removed. */ | |
1024 | if (pr->id == 0) { | |
1025 | pm_idle = pm_idle_save; | |
1026 | ||
1027 | /* | |
1028 | * We are about to unload the current idle thread pm callback | |
1029 | * (pm_idle), Wait for all processors to update cached/local | |
1030 | * copies of pm_idle before proceeding. | |
1031 | */ | |
1032 | cpu_idle_wait(); | |
1033 | } | |
1034 | ||
1035 | return_VALUE(0); | |
1036 | } |