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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() */ |
5c87579e | 41 | #include <linux/latency.h> |
1da177e4 LT |
42 | |
43 | #include <asm/io.h> | |
44 | #include <asm/uaccess.h> | |
45 | ||
46 | #include <acpi/acpi_bus.h> | |
47 | #include <acpi/processor.h> | |
48 | ||
49 | #define ACPI_PROCESSOR_COMPONENT 0x01000000 | |
50 | #define ACPI_PROCESSOR_CLASS "processor" | |
51 | #define ACPI_PROCESSOR_DRIVER_NAME "ACPI Processor Driver" | |
52 | #define _COMPONENT ACPI_PROCESSOR_COMPONENT | |
4be44fcd | 53 | ACPI_MODULE_NAME("acpi_processor") |
1da177e4 | 54 | #define ACPI_PROCESSOR_FILE_POWER "power" |
1da177e4 LT |
55 | #define US_TO_PM_TIMER_TICKS(t) ((t * (PM_TIMER_FREQUENCY/1000)) / 1000) |
56 | #define C2_OVERHEAD 4 /* 1us (3.579 ticks per us) */ | |
57 | #define C3_OVERHEAD 4 /* 1us (3.579 ticks per us) */ | |
b6835052 | 58 | static void (*pm_idle_save) (void) __read_mostly; |
1da177e4 LT |
59 | module_param(max_cstate, uint, 0644); |
60 | ||
b6835052 | 61 | static unsigned int nocst __read_mostly; |
1da177e4 LT |
62 | module_param(nocst, uint, 0000); |
63 | ||
64 | /* | |
65 | * bm_history -- bit-mask with a bit per jiffy of bus-master activity | |
66 | * 1000 HZ: 0xFFFFFFFF: 32 jiffies = 32ms | |
67 | * 800 HZ: 0xFFFFFFFF: 32 jiffies = 40ms | |
68 | * 100 HZ: 0x0000000F: 4 jiffies = 40ms | |
69 | * reduce history for more aggressive entry into C3 | |
70 | */ | |
b6835052 | 71 | static unsigned int bm_history __read_mostly = |
4be44fcd | 72 | (HZ >= 800 ? 0xFFFFFFFF : ((1U << (HZ / 25)) - 1)); |
1da177e4 LT |
73 | module_param(bm_history, uint, 0644); |
74 | /* -------------------------------------------------------------------------- | |
75 | Power Management | |
76 | -------------------------------------------------------------------------- */ | |
77 | ||
78 | /* | |
79 | * IBM ThinkPad R40e crashes mysteriously when going into C2 or C3. | |
80 | * For now disable this. Probably a bug somewhere else. | |
81 | * | |
82 | * To skip this limit, boot/load with a large max_cstate limit. | |
83 | */ | |
335f16be | 84 | static int set_max_cstate(struct dmi_system_id *id) |
1da177e4 LT |
85 | { |
86 | if (max_cstate > ACPI_PROCESSOR_MAX_POWER) | |
87 | return 0; | |
88 | ||
3d35600a | 89 | printk(KERN_NOTICE PREFIX "%s detected - limiting to C%ld max_cstate." |
4be44fcd LB |
90 | " Override with \"processor.max_cstate=%d\"\n", id->ident, |
91 | (long)id->driver_data, ACPI_PROCESSOR_MAX_POWER + 1); | |
1da177e4 | 92 | |
3d35600a | 93 | max_cstate = (long)id->driver_data; |
1da177e4 LT |
94 | |
95 | return 0; | |
96 | } | |
97 | ||
7ded5689 AR |
98 | /* Actually this shouldn't be __cpuinitdata, would be better to fix the |
99 | callers to only run once -AK */ | |
100 | static struct dmi_system_id __cpuinitdata processor_power_dmi_table[] = { | |
f831335d BS |
101 | { set_max_cstate, "IBM ThinkPad R40e", { |
102 | DMI_MATCH(DMI_BIOS_VENDOR,"IBM"), | |
103 | DMI_MATCH(DMI_BIOS_VERSION,"1SET70WW")}, (void *)1}, | |
876c184b TR |
104 | { set_max_cstate, "IBM ThinkPad R40e", { |
105 | DMI_MATCH(DMI_BIOS_VENDOR,"IBM"), | |
106 | DMI_MATCH(DMI_BIOS_VERSION,"1SET60WW")}, (void *)1}, | |
107 | { set_max_cstate, "IBM ThinkPad R40e", { | |
108 | DMI_MATCH(DMI_BIOS_VENDOR,"IBM"), | |
109 | DMI_MATCH(DMI_BIOS_VERSION,"1SET43WW") }, (void*)1}, | |
110 | { set_max_cstate, "IBM ThinkPad R40e", { | |
111 | DMI_MATCH(DMI_BIOS_VENDOR,"IBM"), | |
112 | DMI_MATCH(DMI_BIOS_VERSION,"1SET45WW") }, (void*)1}, | |
113 | { set_max_cstate, "IBM ThinkPad R40e", { | |
114 | DMI_MATCH(DMI_BIOS_VENDOR,"IBM"), | |
115 | DMI_MATCH(DMI_BIOS_VERSION,"1SET47WW") }, (void*)1}, | |
116 | { set_max_cstate, "IBM ThinkPad R40e", { | |
117 | DMI_MATCH(DMI_BIOS_VENDOR,"IBM"), | |
118 | DMI_MATCH(DMI_BIOS_VERSION,"1SET50WW") }, (void*)1}, | |
119 | { set_max_cstate, "IBM ThinkPad R40e", { | |
120 | DMI_MATCH(DMI_BIOS_VENDOR,"IBM"), | |
121 | DMI_MATCH(DMI_BIOS_VERSION,"1SET52WW") }, (void*)1}, | |
122 | { set_max_cstate, "IBM ThinkPad R40e", { | |
123 | DMI_MATCH(DMI_BIOS_VENDOR,"IBM"), | |
124 | DMI_MATCH(DMI_BIOS_VERSION,"1SET55WW") }, (void*)1}, | |
125 | { set_max_cstate, "IBM ThinkPad R40e", { | |
126 | DMI_MATCH(DMI_BIOS_VENDOR,"IBM"), | |
127 | DMI_MATCH(DMI_BIOS_VERSION,"1SET56WW") }, (void*)1}, | |
128 | { set_max_cstate, "IBM ThinkPad R40e", { | |
129 | DMI_MATCH(DMI_BIOS_VENDOR,"IBM"), | |
130 | DMI_MATCH(DMI_BIOS_VERSION,"1SET59WW") }, (void*)1}, | |
131 | { set_max_cstate, "IBM ThinkPad R40e", { | |
132 | DMI_MATCH(DMI_BIOS_VENDOR,"IBM"), | |
133 | DMI_MATCH(DMI_BIOS_VERSION,"1SET60WW") }, (void*)1}, | |
134 | { set_max_cstate, "IBM ThinkPad R40e", { | |
135 | DMI_MATCH(DMI_BIOS_VENDOR,"IBM"), | |
136 | DMI_MATCH(DMI_BIOS_VERSION,"1SET61WW") }, (void*)1}, | |
137 | { set_max_cstate, "IBM ThinkPad R40e", { | |
138 | DMI_MATCH(DMI_BIOS_VENDOR,"IBM"), | |
139 | DMI_MATCH(DMI_BIOS_VERSION,"1SET62WW") }, (void*)1}, | |
140 | { set_max_cstate, "IBM ThinkPad R40e", { | |
141 | DMI_MATCH(DMI_BIOS_VENDOR,"IBM"), | |
142 | DMI_MATCH(DMI_BIOS_VERSION,"1SET64WW") }, (void*)1}, | |
143 | { set_max_cstate, "IBM ThinkPad R40e", { | |
144 | DMI_MATCH(DMI_BIOS_VENDOR,"IBM"), | |
145 | DMI_MATCH(DMI_BIOS_VERSION,"1SET65WW") }, (void*)1}, | |
146 | { set_max_cstate, "IBM ThinkPad R40e", { | |
147 | DMI_MATCH(DMI_BIOS_VENDOR,"IBM"), | |
148 | DMI_MATCH(DMI_BIOS_VERSION,"1SET68WW") }, (void*)1}, | |
149 | { set_max_cstate, "Medion 41700", { | |
150 | DMI_MATCH(DMI_BIOS_VENDOR,"Phoenix Technologies LTD"), | |
151 | DMI_MATCH(DMI_BIOS_VERSION,"R01-A1J")}, (void *)1}, | |
152 | { set_max_cstate, "Clevo 5600D", { | |
153 | DMI_MATCH(DMI_BIOS_VENDOR,"Phoenix Technologies LTD"), | |
154 | DMI_MATCH(DMI_BIOS_VERSION,"SHE845M0.86C.0013.D.0302131307")}, | |
4be44fcd | 155 | (void *)2}, |
1da177e4 LT |
156 | {}, |
157 | }; | |
158 | ||
4be44fcd | 159 | static inline u32 ticks_elapsed(u32 t1, u32 t2) |
1da177e4 LT |
160 | { |
161 | if (t2 >= t1) | |
162 | return (t2 - t1); | |
cee324b1 | 163 | else if (!(acpi_gbl_FADT.flags & ACPI_FADT_32BIT_TIMER)) |
1da177e4 LT |
164 | return (((0x00FFFFFF - t1) + t2) & 0x00FFFFFF); |
165 | else | |
166 | return ((0xFFFFFFFF - t1) + t2); | |
167 | } | |
168 | ||
1da177e4 | 169 | static void |
4be44fcd LB |
170 | acpi_processor_power_activate(struct acpi_processor *pr, |
171 | struct acpi_processor_cx *new) | |
1da177e4 | 172 | { |
4be44fcd | 173 | struct acpi_processor_cx *old; |
1da177e4 LT |
174 | |
175 | if (!pr || !new) | |
176 | return; | |
177 | ||
178 | old = pr->power.state; | |
179 | ||
180 | if (old) | |
181 | old->promotion.count = 0; | |
4be44fcd | 182 | new->demotion.count = 0; |
1da177e4 LT |
183 | |
184 | /* Cleanup from old state. */ | |
185 | if (old) { | |
186 | switch (old->type) { | |
187 | case ACPI_STATE_C3: | |
188 | /* Disable bus master reload */ | |
02df8b93 | 189 | if (new->type != ACPI_STATE_C3 && pr->flags.bm_check) |
d8c71b6d | 190 | acpi_set_register(ACPI_BITREG_BUS_MASTER_RLD, 0); |
1da177e4 LT |
191 | break; |
192 | } | |
193 | } | |
194 | ||
195 | /* Prepare to use new state. */ | |
196 | switch (new->type) { | |
197 | case ACPI_STATE_C3: | |
198 | /* Enable bus master reload */ | |
02df8b93 | 199 | if (old->type != ACPI_STATE_C3 && pr->flags.bm_check) |
d8c71b6d | 200 | acpi_set_register(ACPI_BITREG_BUS_MASTER_RLD, 1); |
1da177e4 LT |
201 | break; |
202 | } | |
203 | ||
204 | pr->power.state = new; | |
205 | ||
206 | return; | |
207 | } | |
208 | ||
64c7c8f8 NP |
209 | static void acpi_safe_halt(void) |
210 | { | |
495ab9c0 | 211 | current_thread_info()->status &= ~TS_POLLING; |
0888f06a IM |
212 | /* |
213 | * TS_POLLING-cleared state must be visible before we | |
214 | * test NEED_RESCHED: | |
215 | */ | |
216 | smp_mb(); | |
64c7c8f8 NP |
217 | if (!need_resched()) |
218 | safe_halt(); | |
495ab9c0 | 219 | current_thread_info()->status |= TS_POLLING; |
64c7c8f8 NP |
220 | } |
221 | ||
4be44fcd | 222 | static atomic_t c3_cpu_count; |
1da177e4 | 223 | |
991528d7 VP |
224 | /* Common C-state entry for C2, C3, .. */ |
225 | static void acpi_cstate_enter(struct acpi_processor_cx *cstate) | |
226 | { | |
227 | if (cstate->space_id == ACPI_CSTATE_FFH) { | |
228 | /* Call into architectural FFH based C-state */ | |
229 | acpi_processor_ffh_cstate_enter(cstate); | |
230 | } else { | |
231 | int unused; | |
232 | /* IO port based C-state */ | |
233 | inb(cstate->address); | |
234 | /* Dummy wait op - must do something useless after P_LVL2 read | |
235 | because chipsets cannot guarantee that STPCLK# signal | |
236 | gets asserted in time to freeze execution properly. */ | |
cee324b1 | 237 | unused = inl(acpi_gbl_FADT.xpm_timer_block.address); |
991528d7 VP |
238 | } |
239 | } | |
240 | ||
4be44fcd | 241 | static void acpi_processor_idle(void) |
1da177e4 | 242 | { |
4be44fcd | 243 | struct acpi_processor *pr = NULL; |
1da177e4 LT |
244 | struct acpi_processor_cx *cx = NULL; |
245 | struct acpi_processor_cx *next_state = NULL; | |
4be44fcd LB |
246 | int sleep_ticks = 0; |
247 | u32 t1, t2 = 0; | |
1da177e4 | 248 | |
64c7c8f8 | 249 | pr = processors[smp_processor_id()]; |
1da177e4 LT |
250 | if (!pr) |
251 | return; | |
252 | ||
253 | /* | |
254 | * Interrupts must be disabled during bus mastering calculations and | |
255 | * for C2/C3 transitions. | |
256 | */ | |
257 | local_irq_disable(); | |
258 | ||
259 | /* | |
260 | * Check whether we truly need to go idle, or should | |
261 | * reschedule: | |
262 | */ | |
263 | if (unlikely(need_resched())) { | |
264 | local_irq_enable(); | |
265 | return; | |
266 | } | |
267 | ||
268 | cx = pr->power.state; | |
64c7c8f8 NP |
269 | if (!cx) { |
270 | if (pm_idle_save) | |
271 | pm_idle_save(); | |
272 | else | |
273 | acpi_safe_halt(); | |
274 | return; | |
275 | } | |
1da177e4 LT |
276 | |
277 | /* | |
278 | * Check BM Activity | |
279 | * ----------------- | |
280 | * Check for bus mastering activity (if required), record, and check | |
281 | * for demotion. | |
282 | */ | |
283 | if (pr->flags.bm_check) { | |
4be44fcd LB |
284 | u32 bm_status = 0; |
285 | unsigned long diff = jiffies - pr->power.bm_check_timestamp; | |
1da177e4 | 286 | |
c5ab81ca DB |
287 | if (diff > 31) |
288 | diff = 31; | |
1da177e4 | 289 | |
c5ab81ca | 290 | pr->power.bm_activity <<= diff; |
1da177e4 | 291 | |
d8c71b6d | 292 | acpi_get_register(ACPI_BITREG_BUS_MASTER_STATUS, &bm_status); |
1da177e4 | 293 | if (bm_status) { |
c5ab81ca | 294 | pr->power.bm_activity |= 0x1; |
d8c71b6d | 295 | acpi_set_register(ACPI_BITREG_BUS_MASTER_STATUS, 1); |
1da177e4 LT |
296 | } |
297 | /* | |
298 | * PIIX4 Erratum #18: Note that BM_STS doesn't always reflect | |
299 | * the true state of bus mastering activity; forcing us to | |
300 | * manually check the BMIDEA bit of each IDE channel. | |
301 | */ | |
302 | else if (errata.piix4.bmisx) { | |
303 | if ((inb_p(errata.piix4.bmisx + 0x02) & 0x01) | |
4be44fcd | 304 | || (inb_p(errata.piix4.bmisx + 0x0A) & 0x01)) |
c5ab81ca | 305 | pr->power.bm_activity |= 0x1; |
1da177e4 LT |
306 | } |
307 | ||
308 | pr->power.bm_check_timestamp = jiffies; | |
309 | ||
310 | /* | |
c4a001b1 | 311 | * If bus mastering is or was active this jiffy, demote |
1da177e4 LT |
312 | * to avoid a faulty transition. Note that the processor |
313 | * won't enter a low-power state during this call (to this | |
c4a001b1 | 314 | * function) but should upon the next. |
1da177e4 LT |
315 | * |
316 | * TBD: A better policy might be to fallback to the demotion | |
317 | * state (use it for this quantum only) istead of | |
318 | * demoting -- and rely on duration as our sole demotion | |
319 | * qualification. This may, however, introduce DMA | |
320 | * issues (e.g. floppy DMA transfer overrun/underrun). | |
321 | */ | |
c4a001b1 DB |
322 | if ((pr->power.bm_activity & 0x1) && |
323 | cx->demotion.threshold.bm) { | |
1da177e4 LT |
324 | local_irq_enable(); |
325 | next_state = cx->demotion.state; | |
326 | goto end; | |
327 | } | |
328 | } | |
329 | ||
4c033552 VP |
330 | #ifdef CONFIG_HOTPLUG_CPU |
331 | /* | |
332 | * Check for P_LVL2_UP flag before entering C2 and above on | |
333 | * an SMP system. We do it here instead of doing it at _CST/P_LVL | |
334 | * detection phase, to work cleanly with logical CPU hotplug. | |
335 | */ | |
336 | if ((cx->type != ACPI_STATE_C1) && (num_online_cpus() > 1) && | |
cee324b1 | 337 | !pr->flags.has_cst && !(acpi_gbl_FADT.flags & ACPI_FADT_C2_MP_SUPPORTED)) |
1e483969 | 338 | cx = &pr->power.states[ACPI_STATE_C1]; |
4c033552 | 339 | #endif |
1e483969 | 340 | |
1da177e4 LT |
341 | /* |
342 | * Sleep: | |
343 | * ------ | |
344 | * Invoke the current Cx state to put the processor to sleep. | |
345 | */ | |
2a298a35 | 346 | if (cx->type == ACPI_STATE_C2 || cx->type == ACPI_STATE_C3) { |
495ab9c0 | 347 | current_thread_info()->status &= ~TS_POLLING; |
0888f06a IM |
348 | /* |
349 | * TS_POLLING-cleared state must be visible before we | |
350 | * test NEED_RESCHED: | |
351 | */ | |
352 | smp_mb(); | |
2a298a35 | 353 | if (need_resched()) { |
495ab9c0 | 354 | current_thread_info()->status |= TS_POLLING; |
af2eb17b | 355 | local_irq_enable(); |
2a298a35 NP |
356 | return; |
357 | } | |
358 | } | |
359 | ||
1da177e4 LT |
360 | switch (cx->type) { |
361 | ||
362 | case ACPI_STATE_C1: | |
363 | /* | |
364 | * Invoke C1. | |
365 | * Use the appropriate idle routine, the one that would | |
366 | * be used without acpi C-states. | |
367 | */ | |
368 | if (pm_idle_save) | |
369 | pm_idle_save(); | |
370 | else | |
64c7c8f8 NP |
371 | acpi_safe_halt(); |
372 | ||
1da177e4 | 373 | /* |
4be44fcd | 374 | * TBD: Can't get time duration while in C1, as resumes |
1da177e4 LT |
375 | * go to an ISR rather than here. Need to instrument |
376 | * base interrupt handler. | |
377 | */ | |
378 | sleep_ticks = 0xFFFFFFFF; | |
379 | break; | |
380 | ||
381 | case ACPI_STATE_C2: | |
382 | /* Get start time (ticks) */ | |
cee324b1 | 383 | t1 = inl(acpi_gbl_FADT.xpm_timer_block.address); |
1da177e4 | 384 | /* Invoke C2 */ |
991528d7 | 385 | acpi_cstate_enter(cx); |
1da177e4 | 386 | /* Get end time (ticks) */ |
cee324b1 | 387 | t2 = inl(acpi_gbl_FADT.xpm_timer_block.address); |
539eb11e JS |
388 | |
389 | #ifdef CONFIG_GENERIC_TIME | |
390 | /* TSC halts in C2, so notify users */ | |
391 | mark_tsc_unstable(); | |
392 | #endif | |
1da177e4 LT |
393 | /* Re-enable interrupts */ |
394 | local_irq_enable(); | |
495ab9c0 | 395 | current_thread_info()->status |= TS_POLLING; |
1da177e4 | 396 | /* Compute time (ticks) that we were actually asleep */ |
4be44fcd LB |
397 | sleep_ticks = |
398 | ticks_elapsed(t1, t2) - cx->latency_ticks - C2_OVERHEAD; | |
1da177e4 LT |
399 | break; |
400 | ||
401 | case ACPI_STATE_C3: | |
4be44fcd | 402 | |
02df8b93 VP |
403 | if (pr->flags.bm_check) { |
404 | if (atomic_inc_return(&c3_cpu_count) == | |
4be44fcd | 405 | num_online_cpus()) { |
02df8b93 VP |
406 | /* |
407 | * All CPUs are trying to go to C3 | |
408 | * Disable bus master arbitration | |
409 | */ | |
d8c71b6d | 410 | acpi_set_register(ACPI_BITREG_ARB_DISABLE, 1); |
02df8b93 VP |
411 | } |
412 | } else { | |
413 | /* SMP with no shared cache... Invalidate cache */ | |
414 | ACPI_FLUSH_CPU_CACHE(); | |
415 | } | |
4be44fcd | 416 | |
1da177e4 | 417 | /* Get start time (ticks) */ |
cee324b1 | 418 | t1 = inl(acpi_gbl_FADT.xpm_timer_block.address); |
1da177e4 | 419 | /* Invoke C3 */ |
991528d7 | 420 | acpi_cstate_enter(cx); |
1da177e4 | 421 | /* Get end time (ticks) */ |
cee324b1 | 422 | t2 = inl(acpi_gbl_FADT.xpm_timer_block.address); |
02df8b93 VP |
423 | if (pr->flags.bm_check) { |
424 | /* Enable bus master arbitration */ | |
425 | atomic_dec(&c3_cpu_count); | |
d8c71b6d | 426 | acpi_set_register(ACPI_BITREG_ARB_DISABLE, 0); |
02df8b93 VP |
427 | } |
428 | ||
539eb11e JS |
429 | #ifdef CONFIG_GENERIC_TIME |
430 | /* TSC halts in C3, so notify users */ | |
431 | mark_tsc_unstable(); | |
432 | #endif | |
1da177e4 LT |
433 | /* Re-enable interrupts */ |
434 | local_irq_enable(); | |
495ab9c0 | 435 | current_thread_info()->status |= TS_POLLING; |
1da177e4 | 436 | /* Compute time (ticks) that we were actually asleep */ |
4be44fcd LB |
437 | sleep_ticks = |
438 | ticks_elapsed(t1, t2) - cx->latency_ticks - C3_OVERHEAD; | |
1da177e4 LT |
439 | break; |
440 | ||
441 | default: | |
442 | local_irq_enable(); | |
443 | return; | |
444 | } | |
a3c6598f DB |
445 | cx->usage++; |
446 | if ((cx->type != ACPI_STATE_C1) && (sleep_ticks > 0)) | |
447 | cx->time += sleep_ticks; | |
1da177e4 LT |
448 | |
449 | next_state = pr->power.state; | |
450 | ||
1e483969 DSL |
451 | #ifdef CONFIG_HOTPLUG_CPU |
452 | /* Don't do promotion/demotion */ | |
453 | if ((cx->type == ACPI_STATE_C1) && (num_online_cpus() > 1) && | |
cee324b1 | 454 | !pr->flags.has_cst && !(acpi_gbl_FADT.flags & ACPI_FADT_C2_MP_SUPPORTED)) { |
1e483969 DSL |
455 | next_state = cx; |
456 | goto end; | |
457 | } | |
458 | #endif | |
459 | ||
1da177e4 LT |
460 | /* |
461 | * Promotion? | |
462 | * ---------- | |
463 | * Track the number of longs (time asleep is greater than threshold) | |
464 | * and promote when the count threshold is reached. Note that bus | |
465 | * mastering activity may prevent promotions. | |
466 | * Do not promote above max_cstate. | |
467 | */ | |
468 | if (cx->promotion.state && | |
469 | ((cx->promotion.state - pr->power.states) <= max_cstate)) { | |
5c87579e AV |
470 | if (sleep_ticks > cx->promotion.threshold.ticks && |
471 | cx->promotion.state->latency <= system_latency_constraint()) { | |
1da177e4 | 472 | cx->promotion.count++; |
4be44fcd LB |
473 | cx->demotion.count = 0; |
474 | if (cx->promotion.count >= | |
475 | cx->promotion.threshold.count) { | |
1da177e4 | 476 | if (pr->flags.bm_check) { |
4be44fcd LB |
477 | if (! |
478 | (pr->power.bm_activity & cx-> | |
479 | promotion.threshold.bm)) { | |
480 | next_state = | |
481 | cx->promotion.state; | |
1da177e4 LT |
482 | goto end; |
483 | } | |
4be44fcd | 484 | } else { |
1da177e4 LT |
485 | next_state = cx->promotion.state; |
486 | goto end; | |
487 | } | |
488 | } | |
489 | } | |
490 | } | |
491 | ||
492 | /* | |
493 | * Demotion? | |
494 | * --------- | |
495 | * Track the number of shorts (time asleep is less than time threshold) | |
496 | * and demote when the usage threshold is reached. | |
497 | */ | |
498 | if (cx->demotion.state) { | |
499 | if (sleep_ticks < cx->demotion.threshold.ticks) { | |
500 | cx->demotion.count++; | |
501 | cx->promotion.count = 0; | |
502 | if (cx->demotion.count >= cx->demotion.threshold.count) { | |
503 | next_state = cx->demotion.state; | |
504 | goto end; | |
505 | } | |
506 | } | |
507 | } | |
508 | ||
4be44fcd | 509 | end: |
1da177e4 LT |
510 | /* |
511 | * Demote if current state exceeds max_cstate | |
5c87579e | 512 | * or if the latency of the current state is unacceptable |
1da177e4 | 513 | */ |
5c87579e AV |
514 | if ((pr->power.state - pr->power.states) > max_cstate || |
515 | pr->power.state->latency > system_latency_constraint()) { | |
1da177e4 LT |
516 | if (cx->demotion.state) |
517 | next_state = cx->demotion.state; | |
518 | } | |
519 | ||
520 | /* | |
521 | * New Cx State? | |
522 | * ------------- | |
523 | * If we're going to start using a new Cx state we must clean up | |
524 | * from the previous and prepare to use the new. | |
525 | */ | |
526 | if (next_state != pr->power.state) | |
527 | acpi_processor_power_activate(pr, next_state); | |
1da177e4 LT |
528 | } |
529 | ||
4be44fcd | 530 | static int acpi_processor_set_power_policy(struct acpi_processor *pr) |
1da177e4 LT |
531 | { |
532 | unsigned int i; | |
533 | unsigned int state_is_set = 0; | |
534 | struct acpi_processor_cx *lower = NULL; | |
535 | struct acpi_processor_cx *higher = NULL; | |
536 | struct acpi_processor_cx *cx; | |
537 | ||
1da177e4 LT |
538 | |
539 | if (!pr) | |
d550d98d | 540 | return -EINVAL; |
1da177e4 LT |
541 | |
542 | /* | |
543 | * This function sets the default Cx state policy (OS idle handler). | |
544 | * Our scheme is to promote quickly to C2 but more conservatively | |
545 | * to C3. We're favoring C2 for its characteristics of low latency | |
546 | * (quick response), good power savings, and ability to allow bus | |
547 | * mastering activity. Note that the Cx state policy is completely | |
548 | * customizable and can be altered dynamically. | |
549 | */ | |
550 | ||
551 | /* startup state */ | |
4be44fcd | 552 | for (i = 1; i < ACPI_PROCESSOR_MAX_POWER; i++) { |
1da177e4 LT |
553 | cx = &pr->power.states[i]; |
554 | if (!cx->valid) | |
555 | continue; | |
556 | ||
557 | if (!state_is_set) | |
558 | pr->power.state = cx; | |
559 | state_is_set++; | |
560 | break; | |
4be44fcd | 561 | } |
1da177e4 LT |
562 | |
563 | if (!state_is_set) | |
d550d98d | 564 | return -ENODEV; |
1da177e4 LT |
565 | |
566 | /* demotion */ | |
4be44fcd | 567 | for (i = 1; i < ACPI_PROCESSOR_MAX_POWER; i++) { |
1da177e4 LT |
568 | cx = &pr->power.states[i]; |
569 | if (!cx->valid) | |
570 | continue; | |
571 | ||
572 | if (lower) { | |
573 | cx->demotion.state = lower; | |
574 | cx->demotion.threshold.ticks = cx->latency_ticks; | |
575 | cx->demotion.threshold.count = 1; | |
576 | if (cx->type == ACPI_STATE_C3) | |
577 | cx->demotion.threshold.bm = bm_history; | |
578 | } | |
579 | ||
580 | lower = cx; | |
581 | } | |
582 | ||
583 | /* promotion */ | |
584 | for (i = (ACPI_PROCESSOR_MAX_POWER - 1); i > 0; i--) { | |
585 | cx = &pr->power.states[i]; | |
586 | if (!cx->valid) | |
587 | continue; | |
588 | ||
589 | if (higher) { | |
4be44fcd | 590 | cx->promotion.state = higher; |
1da177e4 LT |
591 | cx->promotion.threshold.ticks = cx->latency_ticks; |
592 | if (cx->type >= ACPI_STATE_C2) | |
593 | cx->promotion.threshold.count = 4; | |
594 | else | |
595 | cx->promotion.threshold.count = 10; | |
596 | if (higher->type == ACPI_STATE_C3) | |
597 | cx->promotion.threshold.bm = bm_history; | |
598 | } | |
599 | ||
600 | higher = cx; | |
601 | } | |
602 | ||
d550d98d | 603 | return 0; |
1da177e4 LT |
604 | } |
605 | ||
4be44fcd | 606 | static int acpi_processor_get_power_info_fadt(struct acpi_processor *pr) |
1da177e4 | 607 | { |
1da177e4 LT |
608 | |
609 | if (!pr) | |
d550d98d | 610 | return -EINVAL; |
1da177e4 LT |
611 | |
612 | if (!pr->pblk) | |
d550d98d | 613 | return -ENODEV; |
1da177e4 | 614 | |
1da177e4 | 615 | /* if info is obtained from pblk/fadt, type equals state */ |
1da177e4 LT |
616 | pr->power.states[ACPI_STATE_C2].type = ACPI_STATE_C2; |
617 | pr->power.states[ACPI_STATE_C3].type = ACPI_STATE_C3; | |
618 | ||
4c033552 VP |
619 | #ifndef CONFIG_HOTPLUG_CPU |
620 | /* | |
621 | * Check for P_LVL2_UP flag before entering C2 and above on | |
622 | * an SMP system. | |
623 | */ | |
ad71860a | 624 | if ((num_online_cpus() > 1) && |
cee324b1 | 625 | !(acpi_gbl_FADT.flags & ACPI_FADT_C2_MP_SUPPORTED)) |
d550d98d | 626 | return -ENODEV; |
4c033552 VP |
627 | #endif |
628 | ||
1da177e4 LT |
629 | /* determine C2 and C3 address from pblk */ |
630 | pr->power.states[ACPI_STATE_C2].address = pr->pblk + 4; | |
631 | pr->power.states[ACPI_STATE_C3].address = pr->pblk + 5; | |
632 | ||
633 | /* determine latencies from FADT */ | |
cee324b1 AS |
634 | pr->power.states[ACPI_STATE_C2].latency = acpi_gbl_FADT.C2latency; |
635 | pr->power.states[ACPI_STATE_C3].latency = acpi_gbl_FADT.C3latency; | |
1da177e4 LT |
636 | |
637 | ACPI_DEBUG_PRINT((ACPI_DB_INFO, | |
638 | "lvl2[0x%08x] lvl3[0x%08x]\n", | |
639 | pr->power.states[ACPI_STATE_C2].address, | |
640 | pr->power.states[ACPI_STATE_C3].address)); | |
641 | ||
d550d98d | 642 | return 0; |
1da177e4 LT |
643 | } |
644 | ||
991528d7 | 645 | static int acpi_processor_get_power_info_default(struct acpi_processor *pr) |
acf05f4b | 646 | { |
991528d7 VP |
647 | if (!pr->power.states[ACPI_STATE_C1].valid) { |
648 | /* set the first C-State to C1 */ | |
649 | /* all processors need to support C1 */ | |
650 | pr->power.states[ACPI_STATE_C1].type = ACPI_STATE_C1; | |
651 | pr->power.states[ACPI_STATE_C1].valid = 1; | |
652 | } | |
653 | /* the C0 state only exists as a filler in our array */ | |
acf05f4b | 654 | pr->power.states[ACPI_STATE_C0].valid = 1; |
d550d98d | 655 | return 0; |
acf05f4b VP |
656 | } |
657 | ||
4be44fcd | 658 | static int acpi_processor_get_power_info_cst(struct acpi_processor *pr) |
1da177e4 | 659 | { |
4be44fcd LB |
660 | acpi_status status = 0; |
661 | acpi_integer count; | |
cf824788 | 662 | int current_count; |
4be44fcd LB |
663 | int i; |
664 | struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; | |
665 | union acpi_object *cst; | |
1da177e4 | 666 | |
1da177e4 | 667 | |
1da177e4 | 668 | if (nocst) |
d550d98d | 669 | return -ENODEV; |
1da177e4 | 670 | |
991528d7 | 671 | current_count = 0; |
1da177e4 LT |
672 | |
673 | status = acpi_evaluate_object(pr->handle, "_CST", NULL, &buffer); | |
674 | if (ACPI_FAILURE(status)) { | |
675 | ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No _CST, giving up\n")); | |
d550d98d | 676 | return -ENODEV; |
4be44fcd | 677 | } |
1da177e4 | 678 | |
50dd0969 | 679 | cst = buffer.pointer; |
1da177e4 LT |
680 | |
681 | /* There must be at least 2 elements */ | |
682 | if (!cst || (cst->type != ACPI_TYPE_PACKAGE) || cst->package.count < 2) { | |
6468463a | 683 | printk(KERN_ERR PREFIX "not enough elements in _CST\n"); |
1da177e4 LT |
684 | status = -EFAULT; |
685 | goto end; | |
686 | } | |
687 | ||
688 | count = cst->package.elements[0].integer.value; | |
689 | ||
690 | /* Validate number of power states. */ | |
691 | if (count < 1 || count != cst->package.count - 1) { | |
6468463a | 692 | printk(KERN_ERR PREFIX "count given by _CST is not valid\n"); |
1da177e4 LT |
693 | status = -EFAULT; |
694 | goto end; | |
695 | } | |
696 | ||
1da177e4 LT |
697 | /* Tell driver that at least _CST is supported. */ |
698 | pr->flags.has_cst = 1; | |
699 | ||
700 | for (i = 1; i <= count; i++) { | |
701 | union acpi_object *element; | |
702 | union acpi_object *obj; | |
703 | struct acpi_power_register *reg; | |
704 | struct acpi_processor_cx cx; | |
705 | ||
706 | memset(&cx, 0, sizeof(cx)); | |
707 | ||
50dd0969 | 708 | element = &(cst->package.elements[i]); |
1da177e4 LT |
709 | if (element->type != ACPI_TYPE_PACKAGE) |
710 | continue; | |
711 | ||
712 | if (element->package.count != 4) | |
713 | continue; | |
714 | ||
50dd0969 | 715 | obj = &(element->package.elements[0]); |
1da177e4 LT |
716 | |
717 | if (obj->type != ACPI_TYPE_BUFFER) | |
718 | continue; | |
719 | ||
4be44fcd | 720 | reg = (struct acpi_power_register *)obj->buffer.pointer; |
1da177e4 LT |
721 | |
722 | if (reg->space_id != ACPI_ADR_SPACE_SYSTEM_IO && | |
4be44fcd | 723 | (reg->space_id != ACPI_ADR_SPACE_FIXED_HARDWARE)) |
1da177e4 LT |
724 | continue; |
725 | ||
1da177e4 | 726 | /* There should be an easy way to extract an integer... */ |
50dd0969 | 727 | obj = &(element->package.elements[1]); |
1da177e4 LT |
728 | if (obj->type != ACPI_TYPE_INTEGER) |
729 | continue; | |
730 | ||
731 | cx.type = obj->integer.value; | |
991528d7 VP |
732 | /* |
733 | * Some buggy BIOSes won't list C1 in _CST - | |
734 | * Let acpi_processor_get_power_info_default() handle them later | |
735 | */ | |
736 | if (i == 1 && cx.type != ACPI_STATE_C1) | |
737 | current_count++; | |
738 | ||
739 | cx.address = reg->address; | |
740 | cx.index = current_count + 1; | |
741 | ||
742 | cx.space_id = ACPI_CSTATE_SYSTEMIO; | |
743 | if (reg->space_id == ACPI_ADR_SPACE_FIXED_HARDWARE) { | |
744 | if (acpi_processor_ffh_cstate_probe | |
745 | (pr->id, &cx, reg) == 0) { | |
746 | cx.space_id = ACPI_CSTATE_FFH; | |
747 | } else if (cx.type != ACPI_STATE_C1) { | |
748 | /* | |
749 | * C1 is a special case where FIXED_HARDWARE | |
750 | * can be handled in non-MWAIT way as well. | |
751 | * In that case, save this _CST entry info. | |
752 | * That is, we retain space_id of SYSTEM_IO for | |
753 | * halt based C1. | |
754 | * Otherwise, ignore this info and continue. | |
755 | */ | |
756 | continue; | |
757 | } | |
758 | } | |
1da177e4 | 759 | |
50dd0969 | 760 | obj = &(element->package.elements[2]); |
1da177e4 LT |
761 | if (obj->type != ACPI_TYPE_INTEGER) |
762 | continue; | |
763 | ||
764 | cx.latency = obj->integer.value; | |
765 | ||
50dd0969 | 766 | obj = &(element->package.elements[3]); |
1da177e4 LT |
767 | if (obj->type != ACPI_TYPE_INTEGER) |
768 | continue; | |
769 | ||
770 | cx.power = obj->integer.value; | |
771 | ||
cf824788 JM |
772 | current_count++; |
773 | memcpy(&(pr->power.states[current_count]), &cx, sizeof(cx)); | |
774 | ||
775 | /* | |
776 | * We support total ACPI_PROCESSOR_MAX_POWER - 1 | |
777 | * (From 1 through ACPI_PROCESSOR_MAX_POWER - 1) | |
778 | */ | |
779 | if (current_count >= (ACPI_PROCESSOR_MAX_POWER - 1)) { | |
780 | printk(KERN_WARNING | |
781 | "Limiting number of power states to max (%d)\n", | |
782 | ACPI_PROCESSOR_MAX_POWER); | |
783 | printk(KERN_WARNING | |
784 | "Please increase ACPI_PROCESSOR_MAX_POWER if needed.\n"); | |
785 | break; | |
786 | } | |
1da177e4 LT |
787 | } |
788 | ||
4be44fcd | 789 | ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d power states\n", |
cf824788 | 790 | current_count)); |
1da177e4 LT |
791 | |
792 | /* Validate number of power states discovered */ | |
cf824788 | 793 | if (current_count < 2) |
6d93c648 | 794 | status = -EFAULT; |
1da177e4 | 795 | |
4be44fcd | 796 | end: |
02438d87 | 797 | kfree(buffer.pointer); |
1da177e4 | 798 | |
d550d98d | 799 | return status; |
1da177e4 LT |
800 | } |
801 | ||
1da177e4 LT |
802 | static void acpi_processor_power_verify_c2(struct acpi_processor_cx *cx) |
803 | { | |
1da177e4 LT |
804 | |
805 | if (!cx->address) | |
d550d98d | 806 | return; |
1da177e4 LT |
807 | |
808 | /* | |
809 | * C2 latency must be less than or equal to 100 | |
810 | * microseconds. | |
811 | */ | |
812 | else if (cx->latency > ACPI_PROCESSOR_MAX_C2_LATENCY) { | |
813 | ACPI_DEBUG_PRINT((ACPI_DB_INFO, | |
4be44fcd | 814 | "latency too large [%d]\n", cx->latency)); |
d550d98d | 815 | return; |
1da177e4 LT |
816 | } |
817 | ||
1da177e4 LT |
818 | /* |
819 | * Otherwise we've met all of our C2 requirements. | |
820 | * Normalize the C2 latency to expidite policy | |
821 | */ | |
822 | cx->valid = 1; | |
823 | cx->latency_ticks = US_TO_PM_TIMER_TICKS(cx->latency); | |
824 | ||
d550d98d | 825 | return; |
1da177e4 LT |
826 | } |
827 | ||
4be44fcd LB |
828 | static void acpi_processor_power_verify_c3(struct acpi_processor *pr, |
829 | struct acpi_processor_cx *cx) | |
1da177e4 | 830 | { |
02df8b93 VP |
831 | static int bm_check_flag; |
832 | ||
1da177e4 LT |
833 | |
834 | if (!cx->address) | |
d550d98d | 835 | return; |
1da177e4 LT |
836 | |
837 | /* | |
838 | * C3 latency must be less than or equal to 1000 | |
839 | * microseconds. | |
840 | */ | |
841 | else if (cx->latency > ACPI_PROCESSOR_MAX_C3_LATENCY) { | |
842 | ACPI_DEBUG_PRINT((ACPI_DB_INFO, | |
4be44fcd | 843 | "latency too large [%d]\n", cx->latency)); |
d550d98d | 844 | return; |
1da177e4 LT |
845 | } |
846 | ||
1da177e4 LT |
847 | /* |
848 | * PIIX4 Erratum #18: We don't support C3 when Type-F (fast) | |
849 | * DMA transfers are used by any ISA device to avoid livelock. | |
850 | * Note that we could disable Type-F DMA (as recommended by | |
851 | * the erratum), but this is known to disrupt certain ISA | |
852 | * devices thus we take the conservative approach. | |
853 | */ | |
854 | else if (errata.piix4.fdma) { | |
855 | ACPI_DEBUG_PRINT((ACPI_DB_INFO, | |
4be44fcd | 856 | "C3 not supported on PIIX4 with Type-F DMA\n")); |
d550d98d | 857 | return; |
1da177e4 LT |
858 | } |
859 | ||
02df8b93 VP |
860 | /* All the logic here assumes flags.bm_check is same across all CPUs */ |
861 | if (!bm_check_flag) { | |
862 | /* Determine whether bm_check is needed based on CPU */ | |
863 | acpi_processor_power_init_bm_check(&(pr->flags), pr->id); | |
864 | bm_check_flag = pr->flags.bm_check; | |
865 | } else { | |
866 | pr->flags.bm_check = bm_check_flag; | |
867 | } | |
868 | ||
869 | if (pr->flags.bm_check) { | |
02df8b93 VP |
870 | /* bus mastering control is necessary */ |
871 | if (!pr->flags.bm_control) { | |
872 | ACPI_DEBUG_PRINT((ACPI_DB_INFO, | |
4be44fcd | 873 | "C3 support requires bus mastering control\n")); |
d550d98d | 874 | return; |
02df8b93 VP |
875 | } |
876 | } else { | |
02df8b93 VP |
877 | /* |
878 | * WBINVD should be set in fadt, for C3 state to be | |
879 | * supported on when bm_check is not required. | |
880 | */ | |
cee324b1 | 881 | if (!(acpi_gbl_FADT.flags & ACPI_FADT_WBINVD)) { |
02df8b93 | 882 | ACPI_DEBUG_PRINT((ACPI_DB_INFO, |
4be44fcd LB |
883 | "Cache invalidation should work properly" |
884 | " for C3 to be enabled on SMP systems\n")); | |
d550d98d | 885 | return; |
02df8b93 | 886 | } |
d8c71b6d | 887 | acpi_set_register(ACPI_BITREG_BUS_MASTER_RLD, 0); |
02df8b93 VP |
888 | } |
889 | ||
1da177e4 LT |
890 | /* |
891 | * Otherwise we've met all of our C3 requirements. | |
892 | * Normalize the C3 latency to expidite policy. Enable | |
893 | * checking of bus mastering status (bm_check) so we can | |
894 | * use this in our C3 policy | |
895 | */ | |
896 | cx->valid = 1; | |
897 | cx->latency_ticks = US_TO_PM_TIMER_TICKS(cx->latency); | |
1da177e4 | 898 | |
d550d98d | 899 | return; |
1da177e4 LT |
900 | } |
901 | ||
1da177e4 LT |
902 | static int acpi_processor_power_verify(struct acpi_processor *pr) |
903 | { | |
904 | unsigned int i; | |
905 | unsigned int working = 0; | |
6eb0a0fd | 906 | |
bd663347 | 907 | #ifdef ARCH_APICTIMER_STOPS_ON_C3 |
0b5c59a1 AK |
908 | int timer_broadcast = 0; |
909 | cpumask_t mask = cpumask_of_cpu(pr->id); | |
bd663347 | 910 | on_each_cpu(switch_ipi_to_APIC_timer, &mask, 1, 1); |
6eb0a0fd VP |
911 | #endif |
912 | ||
4be44fcd | 913 | for (i = 1; i < ACPI_PROCESSOR_MAX_POWER; i++) { |
1da177e4 LT |
914 | struct acpi_processor_cx *cx = &pr->power.states[i]; |
915 | ||
916 | switch (cx->type) { | |
917 | case ACPI_STATE_C1: | |
918 | cx->valid = 1; | |
919 | break; | |
920 | ||
921 | case ACPI_STATE_C2: | |
922 | acpi_processor_power_verify_c2(cx); | |
bd663347 AK |
923 | #ifdef ARCH_APICTIMER_STOPS_ON_C3 |
924 | /* Some AMD systems fake C3 as C2, but still | |
925 | have timer troubles */ | |
926 | if (cx->valid && | |
927 | boot_cpu_data.x86_vendor == X86_VENDOR_AMD) | |
928 | timer_broadcast++; | |
929 | #endif | |
1da177e4 LT |
930 | break; |
931 | ||
932 | case ACPI_STATE_C3: | |
933 | acpi_processor_power_verify_c3(pr, cx); | |
6eb0a0fd | 934 | #ifdef ARCH_APICTIMER_STOPS_ON_C3 |
bd663347 AK |
935 | if (cx->valid) |
936 | timer_broadcast++; | |
6eb0a0fd | 937 | #endif |
1da177e4 LT |
938 | break; |
939 | } | |
940 | ||
941 | if (cx->valid) | |
942 | working++; | |
943 | } | |
bd663347 | 944 | |
0b5c59a1 | 945 | #ifdef ARCH_APICTIMER_STOPS_ON_C3 |
bd663347 AK |
946 | if (timer_broadcast) |
947 | on_each_cpu(switch_APIC_timer_to_ipi, &mask, 1, 1); | |
0b5c59a1 | 948 | #endif |
1da177e4 LT |
949 | |
950 | return (working); | |
951 | } | |
952 | ||
4be44fcd | 953 | static int acpi_processor_get_power_info(struct acpi_processor *pr) |
1da177e4 LT |
954 | { |
955 | unsigned int i; | |
956 | int result; | |
957 | ||
1da177e4 LT |
958 | |
959 | /* NOTE: the idle thread may not be running while calling | |
960 | * this function */ | |
961 | ||
991528d7 VP |
962 | /* Zero initialize all the C-states info. */ |
963 | memset(pr->power.states, 0, sizeof(pr->power.states)); | |
964 | ||
1da177e4 | 965 | result = acpi_processor_get_power_info_cst(pr); |
6d93c648 | 966 | if (result == -ENODEV) |
c5a114f1 | 967 | result = acpi_processor_get_power_info_fadt(pr); |
6d93c648 | 968 | |
991528d7 VP |
969 | if (result) |
970 | return result; | |
971 | ||
972 | acpi_processor_get_power_info_default(pr); | |
973 | ||
cf824788 | 974 | pr->power.count = acpi_processor_power_verify(pr); |
1da177e4 LT |
975 | |
976 | /* | |
977 | * Set Default Policy | |
978 | * ------------------ | |
979 | * Now that we know which states are supported, set the default | |
980 | * policy. Note that this policy can be changed dynamically | |
981 | * (e.g. encourage deeper sleeps to conserve battery life when | |
982 | * not on AC). | |
983 | */ | |
984 | result = acpi_processor_set_power_policy(pr); | |
985 | if (result) | |
d550d98d | 986 | return result; |
1da177e4 LT |
987 | |
988 | /* | |
989 | * if one state of type C2 or C3 is available, mark this | |
990 | * CPU as being "idle manageable" | |
991 | */ | |
992 | for (i = 1; i < ACPI_PROCESSOR_MAX_POWER; i++) { | |
acf05f4b | 993 | if (pr->power.states[i].valid) { |
1da177e4 | 994 | pr->power.count = i; |
2203d6ed LT |
995 | if (pr->power.states[i].type >= ACPI_STATE_C2) |
996 | pr->flags.power = 1; | |
acf05f4b | 997 | } |
1da177e4 LT |
998 | } |
999 | ||
d550d98d | 1000 | return 0; |
1da177e4 LT |
1001 | } |
1002 | ||
4be44fcd | 1003 | int acpi_processor_cst_has_changed(struct acpi_processor *pr) |
1da177e4 | 1004 | { |
4be44fcd | 1005 | int result = 0; |
1da177e4 | 1006 | |
1da177e4 LT |
1007 | |
1008 | if (!pr) | |
d550d98d | 1009 | return -EINVAL; |
1da177e4 | 1010 | |
4be44fcd | 1011 | if (nocst) { |
d550d98d | 1012 | return -ENODEV; |
1da177e4 LT |
1013 | } |
1014 | ||
1015 | if (!pr->flags.power_setup_done) | |
d550d98d | 1016 | return -ENODEV; |
1da177e4 LT |
1017 | |
1018 | /* Fall back to the default idle loop */ | |
1019 | pm_idle = pm_idle_save; | |
4be44fcd | 1020 | synchronize_sched(); /* Relies on interrupts forcing exit from idle. */ |
1da177e4 LT |
1021 | |
1022 | pr->flags.power = 0; | |
1023 | result = acpi_processor_get_power_info(pr); | |
1024 | if ((pr->flags.power == 1) && (pr->flags.power_setup_done)) | |
1025 | pm_idle = acpi_processor_idle; | |
1026 | ||
d550d98d | 1027 | return result; |
1da177e4 LT |
1028 | } |
1029 | ||
1030 | /* proc interface */ | |
1031 | ||
1032 | static int acpi_processor_power_seq_show(struct seq_file *seq, void *offset) | |
1033 | { | |
50dd0969 | 1034 | struct acpi_processor *pr = seq->private; |
4be44fcd | 1035 | unsigned int i; |
1da177e4 | 1036 | |
1da177e4 LT |
1037 | |
1038 | if (!pr) | |
1039 | goto end; | |
1040 | ||
1041 | seq_printf(seq, "active state: C%zd\n" | |
4be44fcd | 1042 | "max_cstate: C%d\n" |
5c87579e AV |
1043 | "bus master activity: %08x\n" |
1044 | "maximum allowed latency: %d usec\n", | |
4be44fcd | 1045 | pr->power.state ? pr->power.state - pr->power.states : 0, |
5c87579e AV |
1046 | max_cstate, (unsigned)pr->power.bm_activity, |
1047 | system_latency_constraint()); | |
1da177e4 LT |
1048 | |
1049 | seq_puts(seq, "states:\n"); | |
1050 | ||
1051 | for (i = 1; i <= pr->power.count; i++) { | |
1052 | seq_printf(seq, " %cC%d: ", | |
4be44fcd LB |
1053 | (&pr->power.states[i] == |
1054 | pr->power.state ? '*' : ' '), i); | |
1da177e4 LT |
1055 | |
1056 | if (!pr->power.states[i].valid) { | |
1057 | seq_puts(seq, "<not supported>\n"); | |
1058 | continue; | |
1059 | } | |
1060 | ||
1061 | switch (pr->power.states[i].type) { | |
1062 | case ACPI_STATE_C1: | |
1063 | seq_printf(seq, "type[C1] "); | |
1064 | break; | |
1065 | case ACPI_STATE_C2: | |
1066 | seq_printf(seq, "type[C2] "); | |
1067 | break; | |
1068 | case ACPI_STATE_C3: | |
1069 | seq_printf(seq, "type[C3] "); | |
1070 | break; | |
1071 | default: | |
1072 | seq_printf(seq, "type[--] "); | |
1073 | break; | |
1074 | } | |
1075 | ||
1076 | if (pr->power.states[i].promotion.state) | |
1077 | seq_printf(seq, "promotion[C%zd] ", | |
4be44fcd LB |
1078 | (pr->power.states[i].promotion.state - |
1079 | pr->power.states)); | |
1da177e4 LT |
1080 | else |
1081 | seq_puts(seq, "promotion[--] "); | |
1082 | ||
1083 | if (pr->power.states[i].demotion.state) | |
1084 | seq_printf(seq, "demotion[C%zd] ", | |
4be44fcd LB |
1085 | (pr->power.states[i].demotion.state - |
1086 | pr->power.states)); | |
1da177e4 LT |
1087 | else |
1088 | seq_puts(seq, "demotion[--] "); | |
1089 | ||
a3c6598f | 1090 | seq_printf(seq, "latency[%03d] usage[%08d] duration[%020llu]\n", |
4be44fcd | 1091 | pr->power.states[i].latency, |
a3c6598f | 1092 | pr->power.states[i].usage, |
b0b7eaaf | 1093 | (unsigned long long)pr->power.states[i].time); |
1da177e4 LT |
1094 | } |
1095 | ||
4be44fcd | 1096 | end: |
d550d98d | 1097 | return 0; |
1da177e4 LT |
1098 | } |
1099 | ||
1100 | static int acpi_processor_power_open_fs(struct inode *inode, struct file *file) | |
1101 | { | |
1102 | return single_open(file, acpi_processor_power_seq_show, | |
4be44fcd | 1103 | PDE(inode)->data); |
1da177e4 LT |
1104 | } |
1105 | ||
d7508032 | 1106 | static const struct file_operations acpi_processor_power_fops = { |
4be44fcd LB |
1107 | .open = acpi_processor_power_open_fs, |
1108 | .read = seq_read, | |
1109 | .llseek = seq_lseek, | |
1110 | .release = single_release, | |
1da177e4 LT |
1111 | }; |
1112 | ||
1fec74a9 | 1113 | #ifdef CONFIG_SMP |
5c87579e AV |
1114 | static void smp_callback(void *v) |
1115 | { | |
1116 | /* we already woke the CPU up, nothing more to do */ | |
1117 | } | |
1118 | ||
1119 | /* | |
1120 | * This function gets called when a part of the kernel has a new latency | |
1121 | * requirement. This means we need to get all processors out of their C-state, | |
1122 | * and then recalculate a new suitable C-state. Just do a cross-cpu IPI; that | |
1123 | * wakes them all right up. | |
1124 | */ | |
1125 | static int acpi_processor_latency_notify(struct notifier_block *b, | |
1126 | unsigned long l, void *v) | |
1127 | { | |
1128 | smp_call_function(smp_callback, NULL, 0, 1); | |
1129 | return NOTIFY_OK; | |
1130 | } | |
1131 | ||
1132 | static struct notifier_block acpi_processor_latency_notifier = { | |
1133 | .notifier_call = acpi_processor_latency_notify, | |
1134 | }; | |
1fec74a9 | 1135 | #endif |
5c87579e | 1136 | |
7af8b660 | 1137 | int __cpuinit acpi_processor_power_init(struct acpi_processor *pr, |
4be44fcd | 1138 | struct acpi_device *device) |
1da177e4 | 1139 | { |
4be44fcd | 1140 | acpi_status status = 0; |
b6835052 | 1141 | static int first_run; |
4be44fcd | 1142 | struct proc_dir_entry *entry = NULL; |
1da177e4 LT |
1143 | unsigned int i; |
1144 | ||
1da177e4 LT |
1145 | |
1146 | if (!first_run) { | |
1147 | dmi_check_system(processor_power_dmi_table); | |
1148 | if (max_cstate < ACPI_C_STATES_MAX) | |
4be44fcd LB |
1149 | printk(KERN_NOTICE |
1150 | "ACPI: processor limited to max C-state %d\n", | |
1151 | max_cstate); | |
1da177e4 | 1152 | first_run++; |
1fec74a9 | 1153 | #ifdef CONFIG_SMP |
5c87579e | 1154 | register_latency_notifier(&acpi_processor_latency_notifier); |
1fec74a9 | 1155 | #endif |
1da177e4 LT |
1156 | } |
1157 | ||
02df8b93 | 1158 | if (!pr) |
d550d98d | 1159 | return -EINVAL; |
02df8b93 | 1160 | |
cee324b1 | 1161 | if (acpi_gbl_FADT.cst_control && !nocst) { |
4be44fcd | 1162 | status = |
cee324b1 | 1163 | acpi_os_write_port(acpi_gbl_FADT.smi_command, acpi_gbl_FADT.cst_control, 8); |
1da177e4 | 1164 | if (ACPI_FAILURE(status)) { |
a6fc6720 TR |
1165 | ACPI_EXCEPTION((AE_INFO, status, |
1166 | "Notifying BIOS of _CST ability failed")); | |
1da177e4 LT |
1167 | } |
1168 | } | |
1169 | ||
1170 | acpi_processor_get_power_info(pr); | |
1171 | ||
1172 | /* | |
1173 | * Install the idle handler if processor power management is supported. | |
1174 | * Note that we use previously set idle handler will be used on | |
1175 | * platforms that only support C1. | |
1176 | */ | |
1177 | if ((pr->flags.power) && (!boot_option_idle_override)) { | |
1178 | printk(KERN_INFO PREFIX "CPU%d (power states:", pr->id); | |
1179 | for (i = 1; i <= pr->power.count; i++) | |
1180 | if (pr->power.states[i].valid) | |
4be44fcd LB |
1181 | printk(" C%d[C%d]", i, |
1182 | pr->power.states[i].type); | |
1da177e4 LT |
1183 | printk(")\n"); |
1184 | ||
1185 | if (pr->id == 0) { | |
1186 | pm_idle_save = pm_idle; | |
1187 | pm_idle = acpi_processor_idle; | |
1188 | } | |
1189 | } | |
1190 | ||
1191 | /* 'power' [R] */ | |
1192 | entry = create_proc_entry(ACPI_PROCESSOR_FILE_POWER, | |
4be44fcd | 1193 | S_IRUGO, acpi_device_dir(device)); |
1da177e4 | 1194 | if (!entry) |
a6fc6720 | 1195 | return -EIO; |
1da177e4 LT |
1196 | else { |
1197 | entry->proc_fops = &acpi_processor_power_fops; | |
1198 | entry->data = acpi_driver_data(device); | |
1199 | entry->owner = THIS_MODULE; | |
1200 | } | |
1201 | ||
1202 | pr->flags.power_setup_done = 1; | |
1203 | ||
d550d98d | 1204 | return 0; |
1da177e4 LT |
1205 | } |
1206 | ||
4be44fcd LB |
1207 | int acpi_processor_power_exit(struct acpi_processor *pr, |
1208 | struct acpi_device *device) | |
1da177e4 | 1209 | { |
1da177e4 LT |
1210 | |
1211 | pr->flags.power_setup_done = 0; | |
1212 | ||
1213 | if (acpi_device_dir(device)) | |
4be44fcd LB |
1214 | remove_proc_entry(ACPI_PROCESSOR_FILE_POWER, |
1215 | acpi_device_dir(device)); | |
1da177e4 LT |
1216 | |
1217 | /* Unregister the idle handler when processor #0 is removed. */ | |
1218 | if (pr->id == 0) { | |
1219 | pm_idle = pm_idle_save; | |
1220 | ||
1221 | /* | |
1222 | * We are about to unload the current idle thread pm callback | |
1223 | * (pm_idle), Wait for all processors to update cached/local | |
1224 | * copies of pm_idle before proceeding. | |
1225 | */ | |
1226 | cpu_idle_wait(); | |
1fec74a9 | 1227 | #ifdef CONFIG_SMP |
5c87579e | 1228 | unregister_latency_notifier(&acpi_processor_latency_notifier); |
1fec74a9 | 1229 | #endif |
1da177e4 LT |
1230 | } |
1231 | ||
d550d98d | 1232 | return 0; |
1da177e4 | 1233 | } |