Commit | Line | Data |
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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> | |
c5ab81ca | 6 | * Copyright (C) 2004, 2005 Dominik Brodowski <linux@brodo.de> |
1da177e4 LT |
7 | * Copyright (C) 2004 Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> |
8 | * - Added processor hotplug support | |
02df8b93 VP |
9 | * Copyright (C) 2005 Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> |
10 | * - Added support for C3 on SMP | |
1da177e4 LT |
11 | * |
12 | * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ | |
13 | * | |
14 | * This program is free software; you can redistribute it and/or modify | |
15 | * it under the terms of the GNU General Public License as published by | |
16 | * the Free Software Foundation; either version 2 of the License, or (at | |
17 | * your option) any later version. | |
18 | * | |
19 | * This program is distributed in the hope that it will be useful, but | |
20 | * WITHOUT ANY WARRANTY; without even the implied warranty of | |
21 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
22 | * General Public License for more details. | |
23 | * | |
24 | * You should have received a copy of the GNU General Public License along | |
25 | * with this program; if not, write to the Free Software Foundation, Inc., | |
26 | * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. | |
27 | * | |
28 | * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ | |
29 | */ | |
30 | ||
31 | #include <linux/kernel.h> | |
32 | #include <linux/module.h> | |
33 | #include <linux/init.h> | |
34 | #include <linux/cpufreq.h> | |
35 | #include <linux/proc_fs.h> | |
36 | #include <linux/seq_file.h> | |
37 | #include <linux/acpi.h> | |
38 | #include <linux/dmi.h> | |
39 | #include <linux/moduleparam.h> | |
4e57b681 | 40 | #include <linux/sched.h> /* need_resched() */ |
1da177e4 LT |
41 | |
42 | #include <asm/io.h> | |
43 | #include <asm/uaccess.h> | |
44 | ||
45 | #include <acpi/acpi_bus.h> | |
46 | #include <acpi/processor.h> | |
47 | ||
48 | #define ACPI_PROCESSOR_COMPONENT 0x01000000 | |
49 | #define ACPI_PROCESSOR_CLASS "processor" | |
50 | #define ACPI_PROCESSOR_DRIVER_NAME "ACPI Processor Driver" | |
51 | #define _COMPONENT ACPI_PROCESSOR_COMPONENT | |
4be44fcd | 52 | ACPI_MODULE_NAME("acpi_processor") |
1da177e4 | 53 | #define ACPI_PROCESSOR_FILE_POWER "power" |
1da177e4 LT |
54 | #define US_TO_PM_TIMER_TICKS(t) ((t * (PM_TIMER_FREQUENCY/1000)) / 1000) |
55 | #define C2_OVERHEAD 4 /* 1us (3.579 ticks per us) */ | |
56 | #define C3_OVERHEAD 4 /* 1us (3.579 ticks per us) */ | |
b6835052 | 57 | static void (*pm_idle_save) (void) __read_mostly; |
1da177e4 LT |
58 | module_param(max_cstate, uint, 0644); |
59 | ||
b6835052 | 60 | static unsigned int nocst __read_mostly; |
1da177e4 LT |
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 | */ | |
b6835052 | 70 | static unsigned int bm_history __read_mostly = |
4be44fcd | 71 | (HZ >= 800 ? 0xFFFFFFFF : ((1U << (HZ / 25)) - 1)); |
1da177e4 LT |
72 | module_param(bm_history, uint, 0644); |
73 | /* -------------------------------------------------------------------------- | |
74 | Power Management | |
75 | -------------------------------------------------------------------------- */ | |
76 | ||
77 | /* | |
78 | * IBM ThinkPad R40e crashes mysteriously when going into C2 or C3. | |
79 | * For now disable this. Probably a bug somewhere else. | |
80 | * | |
81 | * To skip this limit, boot/load with a large max_cstate limit. | |
82 | */ | |
335f16be | 83 | static int set_max_cstate(struct dmi_system_id *id) |
1da177e4 LT |
84 | { |
85 | if (max_cstate > ACPI_PROCESSOR_MAX_POWER) | |
86 | return 0; | |
87 | ||
3d35600a | 88 | printk(KERN_NOTICE PREFIX "%s detected - limiting to C%ld max_cstate." |
4be44fcd LB |
89 | " Override with \"processor.max_cstate=%d\"\n", id->ident, |
90 | (long)id->driver_data, ACPI_PROCESSOR_MAX_POWER + 1); | |
1da177e4 | 91 | |
3d35600a | 92 | max_cstate = (long)id->driver_data; |
1da177e4 LT |
93 | |
94 | return 0; | |
95 | } | |
96 | ||
7ded5689 AR |
97 | /* Actually this shouldn't be __cpuinitdata, would be better to fix the |
98 | callers to only run once -AK */ | |
99 | static struct dmi_system_id __cpuinitdata processor_power_dmi_table[] = { | |
876c184b TR |
100 | { set_max_cstate, "IBM ThinkPad R40e", { |
101 | DMI_MATCH(DMI_BIOS_VENDOR,"IBM"), | |
102 | DMI_MATCH(DMI_BIOS_VERSION,"1SET60WW")}, (void *)1}, | |
103 | { set_max_cstate, "IBM ThinkPad R40e", { | |
104 | DMI_MATCH(DMI_BIOS_VENDOR,"IBM"), | |
105 | DMI_MATCH(DMI_BIOS_VERSION,"1SET43WW") }, (void*)1}, | |
106 | { set_max_cstate, "IBM ThinkPad R40e", { | |
107 | DMI_MATCH(DMI_BIOS_VENDOR,"IBM"), | |
108 | DMI_MATCH(DMI_BIOS_VERSION,"1SET45WW") }, (void*)1}, | |
109 | { set_max_cstate, "IBM ThinkPad R40e", { | |
110 | DMI_MATCH(DMI_BIOS_VENDOR,"IBM"), | |
111 | DMI_MATCH(DMI_BIOS_VERSION,"1SET47WW") }, (void*)1}, | |
112 | { set_max_cstate, "IBM ThinkPad R40e", { | |
113 | DMI_MATCH(DMI_BIOS_VENDOR,"IBM"), | |
114 | DMI_MATCH(DMI_BIOS_VERSION,"1SET50WW") }, (void*)1}, | |
115 | { set_max_cstate, "IBM ThinkPad R40e", { | |
116 | DMI_MATCH(DMI_BIOS_VENDOR,"IBM"), | |
117 | DMI_MATCH(DMI_BIOS_VERSION,"1SET52WW") }, (void*)1}, | |
118 | { set_max_cstate, "IBM ThinkPad R40e", { | |
119 | DMI_MATCH(DMI_BIOS_VENDOR,"IBM"), | |
120 | DMI_MATCH(DMI_BIOS_VERSION,"1SET55WW") }, (void*)1}, | |
121 | { set_max_cstate, "IBM ThinkPad R40e", { | |
122 | DMI_MATCH(DMI_BIOS_VENDOR,"IBM"), | |
123 | DMI_MATCH(DMI_BIOS_VERSION,"1SET56WW") }, (void*)1}, | |
124 | { set_max_cstate, "IBM ThinkPad R40e", { | |
125 | DMI_MATCH(DMI_BIOS_VENDOR,"IBM"), | |
126 | DMI_MATCH(DMI_BIOS_VERSION,"1SET59WW") }, (void*)1}, | |
127 | { set_max_cstate, "IBM ThinkPad R40e", { | |
128 | DMI_MATCH(DMI_BIOS_VENDOR,"IBM"), | |
129 | DMI_MATCH(DMI_BIOS_VERSION,"1SET60WW") }, (void*)1}, | |
130 | { set_max_cstate, "IBM ThinkPad R40e", { | |
131 | DMI_MATCH(DMI_BIOS_VENDOR,"IBM"), | |
132 | DMI_MATCH(DMI_BIOS_VERSION,"1SET61WW") }, (void*)1}, | |
133 | { set_max_cstate, "IBM ThinkPad R40e", { | |
134 | DMI_MATCH(DMI_BIOS_VENDOR,"IBM"), | |
135 | DMI_MATCH(DMI_BIOS_VERSION,"1SET62WW") }, (void*)1}, | |
136 | { set_max_cstate, "IBM ThinkPad R40e", { | |
137 | DMI_MATCH(DMI_BIOS_VENDOR,"IBM"), | |
138 | DMI_MATCH(DMI_BIOS_VERSION,"1SET64WW") }, (void*)1}, | |
139 | { set_max_cstate, "IBM ThinkPad R40e", { | |
140 | DMI_MATCH(DMI_BIOS_VENDOR,"IBM"), | |
141 | DMI_MATCH(DMI_BIOS_VERSION,"1SET65WW") }, (void*)1}, | |
142 | { set_max_cstate, "IBM ThinkPad R40e", { | |
143 | DMI_MATCH(DMI_BIOS_VENDOR,"IBM"), | |
144 | DMI_MATCH(DMI_BIOS_VERSION,"1SET68WW") }, (void*)1}, | |
145 | { set_max_cstate, "Medion 41700", { | |
146 | DMI_MATCH(DMI_BIOS_VENDOR,"Phoenix Technologies LTD"), | |
147 | DMI_MATCH(DMI_BIOS_VERSION,"R01-A1J")}, (void *)1}, | |
148 | { set_max_cstate, "Clevo 5600D", { | |
149 | DMI_MATCH(DMI_BIOS_VENDOR,"Phoenix Technologies LTD"), | |
150 | DMI_MATCH(DMI_BIOS_VERSION,"SHE845M0.86C.0013.D.0302131307")}, | |
4be44fcd | 151 | (void *)2}, |
1da177e4 LT |
152 | {}, |
153 | }; | |
154 | ||
4be44fcd | 155 | static inline u32 ticks_elapsed(u32 t1, u32 t2) |
1da177e4 LT |
156 | { |
157 | if (t2 >= t1) | |
158 | return (t2 - t1); | |
159 | else if (!acpi_fadt.tmr_val_ext) | |
160 | return (((0x00FFFFFF - t1) + t2) & 0x00FFFFFF); | |
161 | else | |
162 | return ((0xFFFFFFFF - t1) + t2); | |
163 | } | |
164 | ||
1da177e4 | 165 | static void |
4be44fcd LB |
166 | acpi_processor_power_activate(struct acpi_processor *pr, |
167 | struct acpi_processor_cx *new) | |
1da177e4 | 168 | { |
4be44fcd | 169 | struct acpi_processor_cx *old; |
1da177e4 LT |
170 | |
171 | if (!pr || !new) | |
172 | return; | |
173 | ||
174 | old = pr->power.state; | |
175 | ||
176 | if (old) | |
177 | old->promotion.count = 0; | |
4be44fcd | 178 | new->demotion.count = 0; |
1da177e4 LT |
179 | |
180 | /* Cleanup from old state. */ | |
181 | if (old) { | |
182 | switch (old->type) { | |
183 | case ACPI_STATE_C3: | |
184 | /* Disable bus master reload */ | |
02df8b93 | 185 | if (new->type != ACPI_STATE_C3 && pr->flags.bm_check) |
4be44fcd LB |
186 | acpi_set_register(ACPI_BITREG_BUS_MASTER_RLD, 0, |
187 | ACPI_MTX_DO_NOT_LOCK); | |
1da177e4 LT |
188 | break; |
189 | } | |
190 | } | |
191 | ||
192 | /* Prepare to use new state. */ | |
193 | switch (new->type) { | |
194 | case ACPI_STATE_C3: | |
195 | /* Enable bus master reload */ | |
02df8b93 | 196 | if (old->type != ACPI_STATE_C3 && pr->flags.bm_check) |
4be44fcd LB |
197 | acpi_set_register(ACPI_BITREG_BUS_MASTER_RLD, 1, |
198 | ACPI_MTX_DO_NOT_LOCK); | |
1da177e4 LT |
199 | break; |
200 | } | |
201 | ||
202 | pr->power.state = new; | |
203 | ||
204 | return; | |
205 | } | |
206 | ||
64c7c8f8 NP |
207 | static void acpi_safe_halt(void) |
208 | { | |
495ab9c0 | 209 | current_thread_info()->status &= ~TS_POLLING; |
2a298a35 | 210 | smp_mb__after_clear_bit(); |
64c7c8f8 NP |
211 | if (!need_resched()) |
212 | safe_halt(); | |
495ab9c0 | 213 | current_thread_info()->status |= TS_POLLING; |
64c7c8f8 NP |
214 | } |
215 | ||
4be44fcd | 216 | static atomic_t c3_cpu_count; |
1da177e4 | 217 | |
4be44fcd | 218 | static void acpi_processor_idle(void) |
1da177e4 | 219 | { |
4be44fcd | 220 | struct acpi_processor *pr = NULL; |
1da177e4 LT |
221 | struct acpi_processor_cx *cx = NULL; |
222 | struct acpi_processor_cx *next_state = NULL; | |
4be44fcd LB |
223 | int sleep_ticks = 0; |
224 | u32 t1, t2 = 0; | |
1da177e4 | 225 | |
64c7c8f8 | 226 | pr = processors[smp_processor_id()]; |
1da177e4 LT |
227 | if (!pr) |
228 | return; | |
229 | ||
230 | /* | |
231 | * Interrupts must be disabled during bus mastering calculations and | |
232 | * for C2/C3 transitions. | |
233 | */ | |
234 | local_irq_disable(); | |
235 | ||
236 | /* | |
237 | * Check whether we truly need to go idle, or should | |
238 | * reschedule: | |
239 | */ | |
240 | if (unlikely(need_resched())) { | |
241 | local_irq_enable(); | |
242 | return; | |
243 | } | |
244 | ||
245 | cx = pr->power.state; | |
64c7c8f8 NP |
246 | if (!cx) { |
247 | if (pm_idle_save) | |
248 | pm_idle_save(); | |
249 | else | |
250 | acpi_safe_halt(); | |
251 | return; | |
252 | } | |
1da177e4 LT |
253 | |
254 | /* | |
255 | * Check BM Activity | |
256 | * ----------------- | |
257 | * Check for bus mastering activity (if required), record, and check | |
258 | * for demotion. | |
259 | */ | |
260 | if (pr->flags.bm_check) { | |
4be44fcd LB |
261 | u32 bm_status = 0; |
262 | unsigned long diff = jiffies - pr->power.bm_check_timestamp; | |
1da177e4 | 263 | |
c5ab81ca DB |
264 | if (diff > 31) |
265 | diff = 31; | |
1da177e4 | 266 | |
c5ab81ca | 267 | pr->power.bm_activity <<= diff; |
1da177e4 LT |
268 | |
269 | acpi_get_register(ACPI_BITREG_BUS_MASTER_STATUS, | |
4be44fcd | 270 | &bm_status, ACPI_MTX_DO_NOT_LOCK); |
1da177e4 | 271 | if (bm_status) { |
c5ab81ca | 272 | pr->power.bm_activity |= 0x1; |
1da177e4 | 273 | acpi_set_register(ACPI_BITREG_BUS_MASTER_STATUS, |
4be44fcd | 274 | 1, ACPI_MTX_DO_NOT_LOCK); |
1da177e4 LT |
275 | } |
276 | /* | |
277 | * PIIX4 Erratum #18: Note that BM_STS doesn't always reflect | |
278 | * the true state of bus mastering activity; forcing us to | |
279 | * manually check the BMIDEA bit of each IDE channel. | |
280 | */ | |
281 | else if (errata.piix4.bmisx) { | |
282 | if ((inb_p(errata.piix4.bmisx + 0x02) & 0x01) | |
4be44fcd | 283 | || (inb_p(errata.piix4.bmisx + 0x0A) & 0x01)) |
c5ab81ca | 284 | pr->power.bm_activity |= 0x1; |
1da177e4 LT |
285 | } |
286 | ||
287 | pr->power.bm_check_timestamp = jiffies; | |
288 | ||
289 | /* | |
290 | * Apply bus mastering demotion policy. Automatically demote | |
291 | * to avoid a faulty transition. Note that the processor | |
292 | * won't enter a low-power state during this call (to this | |
293 | * funciton) but should upon the next. | |
294 | * | |
295 | * TBD: A better policy might be to fallback to the demotion | |
296 | * state (use it for this quantum only) istead of | |
297 | * demoting -- and rely on duration as our sole demotion | |
298 | * qualification. This may, however, introduce DMA | |
299 | * issues (e.g. floppy DMA transfer overrun/underrun). | |
300 | */ | |
301 | if (pr->power.bm_activity & cx->demotion.threshold.bm) { | |
302 | local_irq_enable(); | |
303 | next_state = cx->demotion.state; | |
304 | goto end; | |
305 | } | |
306 | } | |
307 | ||
4c033552 VP |
308 | #ifdef CONFIG_HOTPLUG_CPU |
309 | /* | |
310 | * Check for P_LVL2_UP flag before entering C2 and above on | |
311 | * an SMP system. We do it here instead of doing it at _CST/P_LVL | |
312 | * detection phase, to work cleanly with logical CPU hotplug. | |
313 | */ | |
314 | if ((cx->type != ACPI_STATE_C1) && (num_online_cpus() > 1) && | |
1e483969 DSL |
315 | !pr->flags.has_cst && !acpi_fadt.plvl2_up) |
316 | cx = &pr->power.states[ACPI_STATE_C1]; | |
4c033552 | 317 | #endif |
1e483969 | 318 | |
1da177e4 LT |
319 | /* |
320 | * Sleep: | |
321 | * ------ | |
322 | * Invoke the current Cx state to put the processor to sleep. | |
323 | */ | |
2a298a35 | 324 | if (cx->type == ACPI_STATE_C2 || cx->type == ACPI_STATE_C3) { |
495ab9c0 | 325 | current_thread_info()->status &= ~TS_POLLING; |
2a298a35 NP |
326 | smp_mb__after_clear_bit(); |
327 | if (need_resched()) { | |
495ab9c0 | 328 | current_thread_info()->status |= TS_POLLING; |
af2eb17b | 329 | local_irq_enable(); |
2a298a35 NP |
330 | return; |
331 | } | |
332 | } | |
333 | ||
1da177e4 LT |
334 | switch (cx->type) { |
335 | ||
336 | case ACPI_STATE_C1: | |
337 | /* | |
338 | * Invoke C1. | |
339 | * Use the appropriate idle routine, the one that would | |
340 | * be used without acpi C-states. | |
341 | */ | |
342 | if (pm_idle_save) | |
343 | pm_idle_save(); | |
344 | else | |
64c7c8f8 NP |
345 | acpi_safe_halt(); |
346 | ||
1da177e4 | 347 | /* |
4be44fcd | 348 | * TBD: Can't get time duration while in C1, as resumes |
1da177e4 LT |
349 | * go to an ISR rather than here. Need to instrument |
350 | * base interrupt handler. | |
351 | */ | |
352 | sleep_ticks = 0xFFFFFFFF; | |
353 | break; | |
354 | ||
355 | case ACPI_STATE_C2: | |
356 | /* Get start time (ticks) */ | |
357 | t1 = inl(acpi_fadt.xpm_tmr_blk.address); | |
358 | /* Invoke C2 */ | |
359 | inb(cx->address); | |
360 | /* Dummy op - must do something useless after P_LVL2 read */ | |
361 | t2 = inl(acpi_fadt.xpm_tmr_blk.address); | |
362 | /* Get end time (ticks) */ | |
363 | t2 = inl(acpi_fadt.xpm_tmr_blk.address); | |
539eb11e | 364 | |
365 | #ifdef CONFIG_GENERIC_TIME | |
366 | /* TSC halts in C2, so notify users */ | |
367 | mark_tsc_unstable(); | |
368 | #endif | |
1da177e4 LT |
369 | /* Re-enable interrupts */ |
370 | local_irq_enable(); | |
495ab9c0 | 371 | current_thread_info()->status |= TS_POLLING; |
1da177e4 | 372 | /* Compute time (ticks) that we were actually asleep */ |
4be44fcd LB |
373 | sleep_ticks = |
374 | ticks_elapsed(t1, t2) - cx->latency_ticks - C2_OVERHEAD; | |
1da177e4 LT |
375 | break; |
376 | ||
377 | case ACPI_STATE_C3: | |
4be44fcd | 378 | |
02df8b93 VP |
379 | if (pr->flags.bm_check) { |
380 | if (atomic_inc_return(&c3_cpu_count) == | |
4be44fcd | 381 | num_online_cpus()) { |
02df8b93 VP |
382 | /* |
383 | * All CPUs are trying to go to C3 | |
384 | * Disable bus master arbitration | |
385 | */ | |
386 | acpi_set_register(ACPI_BITREG_ARB_DISABLE, 1, | |
4be44fcd | 387 | ACPI_MTX_DO_NOT_LOCK); |
02df8b93 VP |
388 | } |
389 | } else { | |
390 | /* SMP with no shared cache... Invalidate cache */ | |
391 | ACPI_FLUSH_CPU_CACHE(); | |
392 | } | |
4be44fcd | 393 | |
1da177e4 LT |
394 | /* Get start time (ticks) */ |
395 | t1 = inl(acpi_fadt.xpm_tmr_blk.address); | |
396 | /* Invoke C3 */ | |
397 | inb(cx->address); | |
398 | /* Dummy op - must do something useless after P_LVL3 read */ | |
399 | t2 = inl(acpi_fadt.xpm_tmr_blk.address); | |
400 | /* Get end time (ticks) */ | |
401 | t2 = inl(acpi_fadt.xpm_tmr_blk.address); | |
02df8b93 VP |
402 | if (pr->flags.bm_check) { |
403 | /* Enable bus master arbitration */ | |
404 | atomic_dec(&c3_cpu_count); | |
4be44fcd LB |
405 | acpi_set_register(ACPI_BITREG_ARB_DISABLE, 0, |
406 | ACPI_MTX_DO_NOT_LOCK); | |
02df8b93 VP |
407 | } |
408 | ||
539eb11e | 409 | #ifdef CONFIG_GENERIC_TIME |
410 | /* TSC halts in C3, so notify users */ | |
411 | mark_tsc_unstable(); | |
412 | #endif | |
1da177e4 LT |
413 | /* Re-enable interrupts */ |
414 | local_irq_enable(); | |
495ab9c0 | 415 | current_thread_info()->status |= TS_POLLING; |
1da177e4 | 416 | /* Compute time (ticks) that we were actually asleep */ |
4be44fcd LB |
417 | sleep_ticks = |
418 | ticks_elapsed(t1, t2) - cx->latency_ticks - C3_OVERHEAD; | |
1da177e4 LT |
419 | break; |
420 | ||
421 | default: | |
422 | local_irq_enable(); | |
423 | return; | |
424 | } | |
a3c6598f DB |
425 | cx->usage++; |
426 | if ((cx->type != ACPI_STATE_C1) && (sleep_ticks > 0)) | |
427 | cx->time += sleep_ticks; | |
1da177e4 LT |
428 | |
429 | next_state = pr->power.state; | |
430 | ||
1e483969 DSL |
431 | #ifdef CONFIG_HOTPLUG_CPU |
432 | /* Don't do promotion/demotion */ | |
433 | if ((cx->type == ACPI_STATE_C1) && (num_online_cpus() > 1) && | |
434 | !pr->flags.has_cst && !acpi_fadt.plvl2_up) { | |
435 | next_state = cx; | |
436 | goto end; | |
437 | } | |
438 | #endif | |
439 | ||
1da177e4 LT |
440 | /* |
441 | * Promotion? | |
442 | * ---------- | |
443 | * Track the number of longs (time asleep is greater than threshold) | |
444 | * and promote when the count threshold is reached. Note that bus | |
445 | * mastering activity may prevent promotions. | |
446 | * Do not promote above max_cstate. | |
447 | */ | |
448 | if (cx->promotion.state && | |
449 | ((cx->promotion.state - pr->power.states) <= max_cstate)) { | |
450 | if (sleep_ticks > cx->promotion.threshold.ticks) { | |
451 | cx->promotion.count++; | |
4be44fcd LB |
452 | cx->demotion.count = 0; |
453 | if (cx->promotion.count >= | |
454 | cx->promotion.threshold.count) { | |
1da177e4 | 455 | if (pr->flags.bm_check) { |
4be44fcd LB |
456 | if (! |
457 | (pr->power.bm_activity & cx-> | |
458 | promotion.threshold.bm)) { | |
459 | next_state = | |
460 | cx->promotion.state; | |
1da177e4 LT |
461 | goto end; |
462 | } | |
4be44fcd | 463 | } else { |
1da177e4 LT |
464 | next_state = cx->promotion.state; |
465 | goto end; | |
466 | } | |
467 | } | |
468 | } | |
469 | } | |
470 | ||
471 | /* | |
472 | * Demotion? | |
473 | * --------- | |
474 | * Track the number of shorts (time asleep is less than time threshold) | |
475 | * and demote when the usage threshold is reached. | |
476 | */ | |
477 | if (cx->demotion.state) { | |
478 | if (sleep_ticks < cx->demotion.threshold.ticks) { | |
479 | cx->demotion.count++; | |
480 | cx->promotion.count = 0; | |
481 | if (cx->demotion.count >= cx->demotion.threshold.count) { | |
482 | next_state = cx->demotion.state; | |
483 | goto end; | |
484 | } | |
485 | } | |
486 | } | |
487 | ||
4be44fcd | 488 | end: |
1da177e4 LT |
489 | /* |
490 | * Demote if current state exceeds max_cstate | |
491 | */ | |
492 | if ((pr->power.state - pr->power.states) > max_cstate) { | |
493 | if (cx->demotion.state) | |
494 | next_state = cx->demotion.state; | |
495 | } | |
496 | ||
497 | /* | |
498 | * New Cx State? | |
499 | * ------------- | |
500 | * If we're going to start using a new Cx state we must clean up | |
501 | * from the previous and prepare to use the new. | |
502 | */ | |
503 | if (next_state != pr->power.state) | |
504 | acpi_processor_power_activate(pr, next_state); | |
1da177e4 LT |
505 | } |
506 | ||
4be44fcd | 507 | static int acpi_processor_set_power_policy(struct acpi_processor *pr) |
1da177e4 LT |
508 | { |
509 | unsigned int i; | |
510 | unsigned int state_is_set = 0; | |
511 | struct acpi_processor_cx *lower = NULL; | |
512 | struct acpi_processor_cx *higher = NULL; | |
513 | struct acpi_processor_cx *cx; | |
514 | ||
1da177e4 LT |
515 | |
516 | if (!pr) | |
d550d98d | 517 | return -EINVAL; |
1da177e4 LT |
518 | |
519 | /* | |
520 | * This function sets the default Cx state policy (OS idle handler). | |
521 | * Our scheme is to promote quickly to C2 but more conservatively | |
522 | * to C3. We're favoring C2 for its characteristics of low latency | |
523 | * (quick response), good power savings, and ability to allow bus | |
524 | * mastering activity. Note that the Cx state policy is completely | |
525 | * customizable and can be altered dynamically. | |
526 | */ | |
527 | ||
528 | /* startup state */ | |
4be44fcd | 529 | for (i = 1; i < ACPI_PROCESSOR_MAX_POWER; i++) { |
1da177e4 LT |
530 | cx = &pr->power.states[i]; |
531 | if (!cx->valid) | |
532 | continue; | |
533 | ||
534 | if (!state_is_set) | |
535 | pr->power.state = cx; | |
536 | state_is_set++; | |
537 | break; | |
4be44fcd | 538 | } |
1da177e4 LT |
539 | |
540 | if (!state_is_set) | |
d550d98d | 541 | return -ENODEV; |
1da177e4 LT |
542 | |
543 | /* demotion */ | |
4be44fcd | 544 | for (i = 1; i < ACPI_PROCESSOR_MAX_POWER; i++) { |
1da177e4 LT |
545 | cx = &pr->power.states[i]; |
546 | if (!cx->valid) | |
547 | continue; | |
548 | ||
549 | if (lower) { | |
550 | cx->demotion.state = lower; | |
551 | cx->demotion.threshold.ticks = cx->latency_ticks; | |
552 | cx->demotion.threshold.count = 1; | |
553 | if (cx->type == ACPI_STATE_C3) | |
554 | cx->demotion.threshold.bm = bm_history; | |
555 | } | |
556 | ||
557 | lower = cx; | |
558 | } | |
559 | ||
560 | /* promotion */ | |
561 | for (i = (ACPI_PROCESSOR_MAX_POWER - 1); i > 0; i--) { | |
562 | cx = &pr->power.states[i]; | |
563 | if (!cx->valid) | |
564 | continue; | |
565 | ||
566 | if (higher) { | |
4be44fcd | 567 | cx->promotion.state = higher; |
1da177e4 LT |
568 | cx->promotion.threshold.ticks = cx->latency_ticks; |
569 | if (cx->type >= ACPI_STATE_C2) | |
570 | cx->promotion.threshold.count = 4; | |
571 | else | |
572 | cx->promotion.threshold.count = 10; | |
573 | if (higher->type == ACPI_STATE_C3) | |
574 | cx->promotion.threshold.bm = bm_history; | |
575 | } | |
576 | ||
577 | higher = cx; | |
578 | } | |
579 | ||
d550d98d | 580 | return 0; |
1da177e4 LT |
581 | } |
582 | ||
4be44fcd | 583 | static int acpi_processor_get_power_info_fadt(struct acpi_processor *pr) |
1da177e4 | 584 | { |
1da177e4 LT |
585 | |
586 | if (!pr) | |
d550d98d | 587 | return -EINVAL; |
1da177e4 LT |
588 | |
589 | if (!pr->pblk) | |
d550d98d | 590 | return -ENODEV; |
1da177e4 | 591 | |
1da177e4 | 592 | /* if info is obtained from pblk/fadt, type equals state */ |
1da177e4 LT |
593 | pr->power.states[ACPI_STATE_C2].type = ACPI_STATE_C2; |
594 | pr->power.states[ACPI_STATE_C3].type = ACPI_STATE_C3; | |
595 | ||
4c033552 VP |
596 | #ifndef CONFIG_HOTPLUG_CPU |
597 | /* | |
598 | * Check for P_LVL2_UP flag before entering C2 and above on | |
599 | * an SMP system. | |
600 | */ | |
1e483969 | 601 | if ((num_online_cpus() > 1) && !acpi_fadt.plvl2_up) |
d550d98d | 602 | return -ENODEV; |
4c033552 VP |
603 | #endif |
604 | ||
1da177e4 LT |
605 | /* determine C2 and C3 address from pblk */ |
606 | pr->power.states[ACPI_STATE_C2].address = pr->pblk + 4; | |
607 | pr->power.states[ACPI_STATE_C3].address = pr->pblk + 5; | |
608 | ||
609 | /* determine latencies from FADT */ | |
610 | pr->power.states[ACPI_STATE_C2].latency = acpi_fadt.plvl2_lat; | |
611 | pr->power.states[ACPI_STATE_C3].latency = acpi_fadt.plvl3_lat; | |
612 | ||
613 | ACPI_DEBUG_PRINT((ACPI_DB_INFO, | |
614 | "lvl2[0x%08x] lvl3[0x%08x]\n", | |
615 | pr->power.states[ACPI_STATE_C2].address, | |
616 | pr->power.states[ACPI_STATE_C3].address)); | |
617 | ||
d550d98d | 618 | return 0; |
1da177e4 LT |
619 | } |
620 | ||
4be44fcd | 621 | static int acpi_processor_get_power_info_default_c1(struct acpi_processor *pr) |
acf05f4b | 622 | { |
acf05f4b | 623 | |
cf824788 | 624 | /* Zero initialize all the C-states info. */ |
2203d6ed | 625 | memset(pr->power.states, 0, sizeof(pr->power.states)); |
acf05f4b | 626 | |
cf824788 | 627 | /* set the first C-State to C1 */ |
acf05f4b | 628 | pr->power.states[ACPI_STATE_C1].type = ACPI_STATE_C1; |
acf05f4b VP |
629 | |
630 | /* the C0 state only exists as a filler in our array, | |
631 | * and all processors need to support C1 */ | |
632 | pr->power.states[ACPI_STATE_C0].valid = 1; | |
633 | pr->power.states[ACPI_STATE_C1].valid = 1; | |
634 | ||
d550d98d | 635 | return 0; |
acf05f4b VP |
636 | } |
637 | ||
4be44fcd | 638 | static int acpi_processor_get_power_info_cst(struct acpi_processor *pr) |
1da177e4 | 639 | { |
4be44fcd LB |
640 | acpi_status status = 0; |
641 | acpi_integer count; | |
cf824788 | 642 | int current_count; |
4be44fcd LB |
643 | int i; |
644 | struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; | |
645 | union acpi_object *cst; | |
1da177e4 | 646 | |
1da177e4 | 647 | |
1da177e4 | 648 | if (nocst) |
d550d98d | 649 | return -ENODEV; |
1da177e4 | 650 | |
cf824788 JM |
651 | current_count = 1; |
652 | ||
653 | /* Zero initialize C2 onwards and prepare for fresh CST lookup */ | |
654 | for (i = 2; i < ACPI_PROCESSOR_MAX_POWER; i++) | |
655 | memset(&(pr->power.states[i]), 0, | |
656 | sizeof(struct acpi_processor_cx)); | |
1da177e4 LT |
657 | |
658 | status = acpi_evaluate_object(pr->handle, "_CST", NULL, &buffer); | |
659 | if (ACPI_FAILURE(status)) { | |
660 | ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No _CST, giving up\n")); | |
d550d98d | 661 | return -ENODEV; |
4be44fcd | 662 | } |
1da177e4 | 663 | |
4be44fcd | 664 | cst = (union acpi_object *)buffer.pointer; |
1da177e4 LT |
665 | |
666 | /* There must be at least 2 elements */ | |
667 | if (!cst || (cst->type != ACPI_TYPE_PACKAGE) || cst->package.count < 2) { | |
6468463a | 668 | printk(KERN_ERR PREFIX "not enough elements in _CST\n"); |
1da177e4 LT |
669 | status = -EFAULT; |
670 | goto end; | |
671 | } | |
672 | ||
673 | count = cst->package.elements[0].integer.value; | |
674 | ||
675 | /* Validate number of power states. */ | |
676 | if (count < 1 || count != cst->package.count - 1) { | |
6468463a | 677 | printk(KERN_ERR PREFIX "count given by _CST is not valid\n"); |
1da177e4 LT |
678 | status = -EFAULT; |
679 | goto end; | |
680 | } | |
681 | ||
1da177e4 LT |
682 | /* Tell driver that at least _CST is supported. */ |
683 | pr->flags.has_cst = 1; | |
684 | ||
685 | for (i = 1; i <= count; i++) { | |
686 | union acpi_object *element; | |
687 | union acpi_object *obj; | |
688 | struct acpi_power_register *reg; | |
689 | struct acpi_processor_cx cx; | |
690 | ||
691 | memset(&cx, 0, sizeof(cx)); | |
692 | ||
4be44fcd | 693 | element = (union acpi_object *)&(cst->package.elements[i]); |
1da177e4 LT |
694 | if (element->type != ACPI_TYPE_PACKAGE) |
695 | continue; | |
696 | ||
697 | if (element->package.count != 4) | |
698 | continue; | |
699 | ||
4be44fcd | 700 | obj = (union acpi_object *)&(element->package.elements[0]); |
1da177e4 LT |
701 | |
702 | if (obj->type != ACPI_TYPE_BUFFER) | |
703 | continue; | |
704 | ||
4be44fcd | 705 | reg = (struct acpi_power_register *)obj->buffer.pointer; |
1da177e4 LT |
706 | |
707 | if (reg->space_id != ACPI_ADR_SPACE_SYSTEM_IO && | |
4be44fcd | 708 | (reg->space_id != ACPI_ADR_SPACE_FIXED_HARDWARE)) |
1da177e4 LT |
709 | continue; |
710 | ||
711 | cx.address = (reg->space_id == ACPI_ADR_SPACE_FIXED_HARDWARE) ? | |
4be44fcd | 712 | 0 : reg->address; |
1da177e4 LT |
713 | |
714 | /* There should be an easy way to extract an integer... */ | |
4be44fcd | 715 | obj = (union acpi_object *)&(element->package.elements[1]); |
1da177e4 LT |
716 | if (obj->type != ACPI_TYPE_INTEGER) |
717 | continue; | |
718 | ||
719 | cx.type = obj->integer.value; | |
720 | ||
721 | if ((cx.type != ACPI_STATE_C1) && | |
722 | (reg->space_id != ACPI_ADR_SPACE_SYSTEM_IO)) | |
723 | continue; | |
724 | ||
cf824788 | 725 | if ((cx.type < ACPI_STATE_C2) || (cx.type > ACPI_STATE_C3)) |
1da177e4 LT |
726 | continue; |
727 | ||
4be44fcd | 728 | obj = (union acpi_object *)&(element->package.elements[2]); |
1da177e4 LT |
729 | if (obj->type != ACPI_TYPE_INTEGER) |
730 | continue; | |
731 | ||
732 | cx.latency = obj->integer.value; | |
733 | ||
4be44fcd | 734 | obj = (union acpi_object *)&(element->package.elements[3]); |
1da177e4 LT |
735 | if (obj->type != ACPI_TYPE_INTEGER) |
736 | continue; | |
737 | ||
738 | cx.power = obj->integer.value; | |
739 | ||
cf824788 JM |
740 | current_count++; |
741 | memcpy(&(pr->power.states[current_count]), &cx, sizeof(cx)); | |
742 | ||
743 | /* | |
744 | * We support total ACPI_PROCESSOR_MAX_POWER - 1 | |
745 | * (From 1 through ACPI_PROCESSOR_MAX_POWER - 1) | |
746 | */ | |
747 | if (current_count >= (ACPI_PROCESSOR_MAX_POWER - 1)) { | |
748 | printk(KERN_WARNING | |
749 | "Limiting number of power states to max (%d)\n", | |
750 | ACPI_PROCESSOR_MAX_POWER); | |
751 | printk(KERN_WARNING | |
752 | "Please increase ACPI_PROCESSOR_MAX_POWER if needed.\n"); | |
753 | break; | |
754 | } | |
1da177e4 LT |
755 | } |
756 | ||
4be44fcd | 757 | ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d power states\n", |
cf824788 | 758 | current_count)); |
1da177e4 LT |
759 | |
760 | /* Validate number of power states discovered */ | |
cf824788 | 761 | if (current_count < 2) |
6d93c648 | 762 | status = -EFAULT; |
1da177e4 | 763 | |
4be44fcd | 764 | end: |
1da177e4 LT |
765 | acpi_os_free(buffer.pointer); |
766 | ||
d550d98d | 767 | return status; |
1da177e4 LT |
768 | } |
769 | ||
1da177e4 LT |
770 | static void acpi_processor_power_verify_c2(struct acpi_processor_cx *cx) |
771 | { | |
1da177e4 LT |
772 | |
773 | if (!cx->address) | |
d550d98d | 774 | return; |
1da177e4 LT |
775 | |
776 | /* | |
777 | * C2 latency must be less than or equal to 100 | |
778 | * microseconds. | |
779 | */ | |
780 | else if (cx->latency > ACPI_PROCESSOR_MAX_C2_LATENCY) { | |
781 | ACPI_DEBUG_PRINT((ACPI_DB_INFO, | |
4be44fcd | 782 | "latency too large [%d]\n", cx->latency)); |
d550d98d | 783 | return; |
1da177e4 LT |
784 | } |
785 | ||
1da177e4 LT |
786 | /* |
787 | * Otherwise we've met all of our C2 requirements. | |
788 | * Normalize the C2 latency to expidite policy | |
789 | */ | |
790 | cx->valid = 1; | |
791 | cx->latency_ticks = US_TO_PM_TIMER_TICKS(cx->latency); | |
792 | ||
d550d98d | 793 | return; |
1da177e4 LT |
794 | } |
795 | ||
4be44fcd LB |
796 | static void acpi_processor_power_verify_c3(struct acpi_processor *pr, |
797 | struct acpi_processor_cx *cx) | |
1da177e4 | 798 | { |
02df8b93 VP |
799 | static int bm_check_flag; |
800 | ||
1da177e4 LT |
801 | |
802 | if (!cx->address) | |
d550d98d | 803 | return; |
1da177e4 LT |
804 | |
805 | /* | |
806 | * C3 latency must be less than or equal to 1000 | |
807 | * microseconds. | |
808 | */ | |
809 | else if (cx->latency > ACPI_PROCESSOR_MAX_C3_LATENCY) { | |
810 | ACPI_DEBUG_PRINT((ACPI_DB_INFO, | |
4be44fcd | 811 | "latency too large [%d]\n", cx->latency)); |
d550d98d | 812 | return; |
1da177e4 LT |
813 | } |
814 | ||
1da177e4 LT |
815 | /* |
816 | * PIIX4 Erratum #18: We don't support C3 when Type-F (fast) | |
817 | * DMA transfers are used by any ISA device to avoid livelock. | |
818 | * Note that we could disable Type-F DMA (as recommended by | |
819 | * the erratum), but this is known to disrupt certain ISA | |
820 | * devices thus we take the conservative approach. | |
821 | */ | |
822 | else if (errata.piix4.fdma) { | |
823 | ACPI_DEBUG_PRINT((ACPI_DB_INFO, | |
4be44fcd | 824 | "C3 not supported on PIIX4 with Type-F DMA\n")); |
d550d98d | 825 | return; |
1da177e4 LT |
826 | } |
827 | ||
02df8b93 VP |
828 | /* All the logic here assumes flags.bm_check is same across all CPUs */ |
829 | if (!bm_check_flag) { | |
830 | /* Determine whether bm_check is needed based on CPU */ | |
831 | acpi_processor_power_init_bm_check(&(pr->flags), pr->id); | |
832 | bm_check_flag = pr->flags.bm_check; | |
833 | } else { | |
834 | pr->flags.bm_check = bm_check_flag; | |
835 | } | |
836 | ||
837 | if (pr->flags.bm_check) { | |
02df8b93 VP |
838 | /* bus mastering control is necessary */ |
839 | if (!pr->flags.bm_control) { | |
840 | ACPI_DEBUG_PRINT((ACPI_DB_INFO, | |
4be44fcd | 841 | "C3 support requires bus mastering control\n")); |
d550d98d | 842 | return; |
02df8b93 VP |
843 | } |
844 | } else { | |
02df8b93 VP |
845 | /* |
846 | * WBINVD should be set in fadt, for C3 state to be | |
847 | * supported on when bm_check is not required. | |
848 | */ | |
849 | if (acpi_fadt.wb_invd != 1) { | |
850 | ACPI_DEBUG_PRINT((ACPI_DB_INFO, | |
4be44fcd LB |
851 | "Cache invalidation should work properly" |
852 | " for C3 to be enabled on SMP systems\n")); | |
d550d98d | 853 | return; |
02df8b93 VP |
854 | } |
855 | acpi_set_register(ACPI_BITREG_BUS_MASTER_RLD, | |
4be44fcd | 856 | 0, ACPI_MTX_DO_NOT_LOCK); |
02df8b93 VP |
857 | } |
858 | ||
1da177e4 LT |
859 | /* |
860 | * Otherwise we've met all of our C3 requirements. | |
861 | * Normalize the C3 latency to expidite policy. Enable | |
862 | * checking of bus mastering status (bm_check) so we can | |
863 | * use this in our C3 policy | |
864 | */ | |
865 | cx->valid = 1; | |
866 | cx->latency_ticks = US_TO_PM_TIMER_TICKS(cx->latency); | |
1da177e4 | 867 | |
d550d98d | 868 | return; |
1da177e4 LT |
869 | } |
870 | ||
1da177e4 LT |
871 | static int acpi_processor_power_verify(struct acpi_processor *pr) |
872 | { | |
873 | unsigned int i; | |
874 | unsigned int working = 0; | |
6eb0a0fd | 875 | |
bd663347 | 876 | #ifdef ARCH_APICTIMER_STOPS_ON_C3 |
0b5c59a1 AK |
877 | int timer_broadcast = 0; |
878 | cpumask_t mask = cpumask_of_cpu(pr->id); | |
bd663347 | 879 | on_each_cpu(switch_ipi_to_APIC_timer, &mask, 1, 1); |
6eb0a0fd VP |
880 | #endif |
881 | ||
4be44fcd | 882 | for (i = 1; i < ACPI_PROCESSOR_MAX_POWER; i++) { |
1da177e4 LT |
883 | struct acpi_processor_cx *cx = &pr->power.states[i]; |
884 | ||
885 | switch (cx->type) { | |
886 | case ACPI_STATE_C1: | |
887 | cx->valid = 1; | |
888 | break; | |
889 | ||
890 | case ACPI_STATE_C2: | |
891 | acpi_processor_power_verify_c2(cx); | |
bd663347 AK |
892 | #ifdef ARCH_APICTIMER_STOPS_ON_C3 |
893 | /* Some AMD systems fake C3 as C2, but still | |
894 | have timer troubles */ | |
895 | if (cx->valid && | |
896 | boot_cpu_data.x86_vendor == X86_VENDOR_AMD) | |
897 | timer_broadcast++; | |
898 | #endif | |
1da177e4 LT |
899 | break; |
900 | ||
901 | case ACPI_STATE_C3: | |
902 | acpi_processor_power_verify_c3(pr, cx); | |
6eb0a0fd | 903 | #ifdef ARCH_APICTIMER_STOPS_ON_C3 |
bd663347 AK |
904 | if (cx->valid) |
905 | timer_broadcast++; | |
6eb0a0fd | 906 | #endif |
1da177e4 LT |
907 | break; |
908 | } | |
909 | ||
910 | if (cx->valid) | |
911 | working++; | |
912 | } | |
bd663347 | 913 | |
0b5c59a1 | 914 | #ifdef ARCH_APICTIMER_STOPS_ON_C3 |
bd663347 AK |
915 | if (timer_broadcast) |
916 | on_each_cpu(switch_APIC_timer_to_ipi, &mask, 1, 1); | |
0b5c59a1 | 917 | #endif |
1da177e4 LT |
918 | |
919 | return (working); | |
920 | } | |
921 | ||
4be44fcd | 922 | static int acpi_processor_get_power_info(struct acpi_processor *pr) |
1da177e4 LT |
923 | { |
924 | unsigned int i; | |
925 | int result; | |
926 | ||
1da177e4 LT |
927 | |
928 | /* NOTE: the idle thread may not be running while calling | |
929 | * this function */ | |
930 | ||
cf824788 JM |
931 | /* Adding C1 state */ |
932 | acpi_processor_get_power_info_default_c1(pr); | |
1da177e4 | 933 | result = acpi_processor_get_power_info_cst(pr); |
6d93c648 | 934 | if (result == -ENODEV) |
cf824788 | 935 | acpi_processor_get_power_info_fadt(pr); |
6d93c648 | 936 | |
cf824788 | 937 | pr->power.count = acpi_processor_power_verify(pr); |
1da177e4 LT |
938 | |
939 | /* | |
940 | * Set Default Policy | |
941 | * ------------------ | |
942 | * Now that we know which states are supported, set the default | |
943 | * policy. Note that this policy can be changed dynamically | |
944 | * (e.g. encourage deeper sleeps to conserve battery life when | |
945 | * not on AC). | |
946 | */ | |
947 | result = acpi_processor_set_power_policy(pr); | |
948 | if (result) | |
d550d98d | 949 | return result; |
1da177e4 LT |
950 | |
951 | /* | |
952 | * if one state of type C2 or C3 is available, mark this | |
953 | * CPU as being "idle manageable" | |
954 | */ | |
955 | for (i = 1; i < ACPI_PROCESSOR_MAX_POWER; i++) { | |
acf05f4b | 956 | if (pr->power.states[i].valid) { |
1da177e4 | 957 | pr->power.count = i; |
2203d6ed LT |
958 | if (pr->power.states[i].type >= ACPI_STATE_C2) |
959 | pr->flags.power = 1; | |
acf05f4b | 960 | } |
1da177e4 LT |
961 | } |
962 | ||
d550d98d | 963 | return 0; |
1da177e4 LT |
964 | } |
965 | ||
4be44fcd | 966 | int acpi_processor_cst_has_changed(struct acpi_processor *pr) |
1da177e4 | 967 | { |
4be44fcd | 968 | int result = 0; |
1da177e4 | 969 | |
1da177e4 LT |
970 | |
971 | if (!pr) | |
d550d98d | 972 | return -EINVAL; |
1da177e4 | 973 | |
4be44fcd | 974 | if (nocst) { |
d550d98d | 975 | return -ENODEV; |
1da177e4 LT |
976 | } |
977 | ||
978 | if (!pr->flags.power_setup_done) | |
d550d98d | 979 | return -ENODEV; |
1da177e4 LT |
980 | |
981 | /* Fall back to the default idle loop */ | |
982 | pm_idle = pm_idle_save; | |
4be44fcd | 983 | synchronize_sched(); /* Relies on interrupts forcing exit from idle. */ |
1da177e4 LT |
984 | |
985 | pr->flags.power = 0; | |
986 | result = acpi_processor_get_power_info(pr); | |
987 | if ((pr->flags.power == 1) && (pr->flags.power_setup_done)) | |
988 | pm_idle = acpi_processor_idle; | |
989 | ||
d550d98d | 990 | return result; |
1da177e4 LT |
991 | } |
992 | ||
993 | /* proc interface */ | |
994 | ||
995 | static int acpi_processor_power_seq_show(struct seq_file *seq, void *offset) | |
996 | { | |
4be44fcd LB |
997 | struct acpi_processor *pr = (struct acpi_processor *)seq->private; |
998 | unsigned int i; | |
1da177e4 | 999 | |
1da177e4 LT |
1000 | |
1001 | if (!pr) | |
1002 | goto end; | |
1003 | ||
1004 | seq_printf(seq, "active state: C%zd\n" | |
4be44fcd LB |
1005 | "max_cstate: C%d\n" |
1006 | "bus master activity: %08x\n", | |
1007 | pr->power.state ? pr->power.state - pr->power.states : 0, | |
1008 | max_cstate, (unsigned)pr->power.bm_activity); | |
1da177e4 LT |
1009 | |
1010 | seq_puts(seq, "states:\n"); | |
1011 | ||
1012 | for (i = 1; i <= pr->power.count; i++) { | |
1013 | seq_printf(seq, " %cC%d: ", | |
4be44fcd LB |
1014 | (&pr->power.states[i] == |
1015 | pr->power.state ? '*' : ' '), i); | |
1da177e4 LT |
1016 | |
1017 | if (!pr->power.states[i].valid) { | |
1018 | seq_puts(seq, "<not supported>\n"); | |
1019 | continue; | |
1020 | } | |
1021 | ||
1022 | switch (pr->power.states[i].type) { | |
1023 | case ACPI_STATE_C1: | |
1024 | seq_printf(seq, "type[C1] "); | |
1025 | break; | |
1026 | case ACPI_STATE_C2: | |
1027 | seq_printf(seq, "type[C2] "); | |
1028 | break; | |
1029 | case ACPI_STATE_C3: | |
1030 | seq_printf(seq, "type[C3] "); | |
1031 | break; | |
1032 | default: | |
1033 | seq_printf(seq, "type[--] "); | |
1034 | break; | |
1035 | } | |
1036 | ||
1037 | if (pr->power.states[i].promotion.state) | |
1038 | seq_printf(seq, "promotion[C%zd] ", | |
4be44fcd LB |
1039 | (pr->power.states[i].promotion.state - |
1040 | pr->power.states)); | |
1da177e4 LT |
1041 | else |
1042 | seq_puts(seq, "promotion[--] "); | |
1043 | ||
1044 | if (pr->power.states[i].demotion.state) | |
1045 | seq_printf(seq, "demotion[C%zd] ", | |
4be44fcd LB |
1046 | (pr->power.states[i].demotion.state - |
1047 | pr->power.states)); | |
1da177e4 LT |
1048 | else |
1049 | seq_puts(seq, "demotion[--] "); | |
1050 | ||
a3c6598f | 1051 | seq_printf(seq, "latency[%03d] usage[%08d] duration[%020llu]\n", |
4be44fcd | 1052 | pr->power.states[i].latency, |
a3c6598f DB |
1053 | pr->power.states[i].usage, |
1054 | pr->power.states[i].time); | |
1da177e4 LT |
1055 | } |
1056 | ||
4be44fcd | 1057 | end: |
d550d98d | 1058 | return 0; |
1da177e4 LT |
1059 | } |
1060 | ||
1061 | static int acpi_processor_power_open_fs(struct inode *inode, struct file *file) | |
1062 | { | |
1063 | return single_open(file, acpi_processor_power_seq_show, | |
4be44fcd | 1064 | PDE(inode)->data); |
1da177e4 LT |
1065 | } |
1066 | ||
1067 | static struct file_operations acpi_processor_power_fops = { | |
4be44fcd LB |
1068 | .open = acpi_processor_power_open_fs, |
1069 | .read = seq_read, | |
1070 | .llseek = seq_lseek, | |
1071 | .release = single_release, | |
1da177e4 LT |
1072 | }; |
1073 | ||
4be44fcd LB |
1074 | int acpi_processor_power_init(struct acpi_processor *pr, |
1075 | struct acpi_device *device) | |
1da177e4 | 1076 | { |
4be44fcd | 1077 | acpi_status status = 0; |
b6835052 | 1078 | static int first_run; |
4be44fcd | 1079 | struct proc_dir_entry *entry = NULL; |
1da177e4 LT |
1080 | unsigned int i; |
1081 | ||
1da177e4 LT |
1082 | |
1083 | if (!first_run) { | |
1084 | dmi_check_system(processor_power_dmi_table); | |
1085 | if (max_cstate < ACPI_C_STATES_MAX) | |
4be44fcd LB |
1086 | printk(KERN_NOTICE |
1087 | "ACPI: processor limited to max C-state %d\n", | |
1088 | max_cstate); | |
1da177e4 LT |
1089 | first_run++; |
1090 | } | |
1091 | ||
02df8b93 | 1092 | if (!pr) |
d550d98d | 1093 | return -EINVAL; |
02df8b93 VP |
1094 | |
1095 | if (acpi_fadt.cst_cnt && !nocst) { | |
4be44fcd LB |
1096 | status = |
1097 | acpi_os_write_port(acpi_fadt.smi_cmd, acpi_fadt.cst_cnt, 8); | |
1da177e4 | 1098 | if (ACPI_FAILURE(status)) { |
a6fc6720 TR |
1099 | ACPI_EXCEPTION((AE_INFO, status, |
1100 | "Notifying BIOS of _CST ability failed")); | |
1da177e4 LT |
1101 | } |
1102 | } | |
1103 | ||
1104 | acpi_processor_get_power_info(pr); | |
1105 | ||
1106 | /* | |
1107 | * Install the idle handler if processor power management is supported. | |
1108 | * Note that we use previously set idle handler will be used on | |
1109 | * platforms that only support C1. | |
1110 | */ | |
1111 | if ((pr->flags.power) && (!boot_option_idle_override)) { | |
1112 | printk(KERN_INFO PREFIX "CPU%d (power states:", pr->id); | |
1113 | for (i = 1; i <= pr->power.count; i++) | |
1114 | if (pr->power.states[i].valid) | |
4be44fcd LB |
1115 | printk(" C%d[C%d]", i, |
1116 | pr->power.states[i].type); | |
1da177e4 LT |
1117 | printk(")\n"); |
1118 | ||
1119 | if (pr->id == 0) { | |
1120 | pm_idle_save = pm_idle; | |
1121 | pm_idle = acpi_processor_idle; | |
1122 | } | |
1123 | } | |
1124 | ||
1125 | /* 'power' [R] */ | |
1126 | entry = create_proc_entry(ACPI_PROCESSOR_FILE_POWER, | |
4be44fcd | 1127 | S_IRUGO, acpi_device_dir(device)); |
1da177e4 | 1128 | if (!entry) |
a6fc6720 | 1129 | return -EIO; |
1da177e4 LT |
1130 | else { |
1131 | entry->proc_fops = &acpi_processor_power_fops; | |
1132 | entry->data = acpi_driver_data(device); | |
1133 | entry->owner = THIS_MODULE; | |
1134 | } | |
1135 | ||
1136 | pr->flags.power_setup_done = 1; | |
1137 | ||
d550d98d | 1138 | return 0; |
1da177e4 LT |
1139 | } |
1140 | ||
4be44fcd LB |
1141 | int acpi_processor_power_exit(struct acpi_processor *pr, |
1142 | struct acpi_device *device) | |
1da177e4 | 1143 | { |
1da177e4 LT |
1144 | |
1145 | pr->flags.power_setup_done = 0; | |
1146 | ||
1147 | if (acpi_device_dir(device)) | |
4be44fcd LB |
1148 | remove_proc_entry(ACPI_PROCESSOR_FILE_POWER, |
1149 | acpi_device_dir(device)); | |
1da177e4 LT |
1150 | |
1151 | /* Unregister the idle handler when processor #0 is removed. */ | |
1152 | if (pr->id == 0) { | |
1153 | pm_idle = pm_idle_save; | |
1154 | ||
1155 | /* | |
1156 | * We are about to unload the current idle thread pm callback | |
1157 | * (pm_idle), Wait for all processors to update cached/local | |
1158 | * copies of pm_idle before proceeding. | |
1159 | */ | |
1160 | cpu_idle_wait(); | |
1161 | } | |
1162 | ||
d550d98d | 1163 | return 0; |
1da177e4 | 1164 | } |