blob: 07bc74d8356ea2a75188330a87d117da995ea91b [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
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>
Dominik Brodowskic5ab81c2006-06-24 19:37:00 -04006 * Copyright (C) 2004, 2005 Dominik Brodowski <linux@brodo.de>
Linus Torvalds1da177e2005-04-16 15:20:36 -07007 * Copyright (C) 2004 Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
8 * - Added processor hotplug support
Venkatesh Pallipadi02df8b92005-04-15 15:07:10 -04009 * Copyright (C) 2005 Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
10 * - Added support for C3 on SMP
Linus Torvalds1da177e2005-04-16 15:20:36 -070011 *
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>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090035#include <linux/slab.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070036#include <linux/acpi.h>
37#include <linux/dmi.h>
38#include <linux/moduleparam.h>
Tim Schmielau4e57b682005-10-30 15:03:48 -080039#include <linux/sched.h> /* need_resched() */
Mark Grossf011e2e2008-02-04 22:30:09 -080040#include <linux/pm_qos_params.h>
Thomas Gleixnere9e2cdb2007-02-16 01:28:04 -080041#include <linux/clockchips.h>
Len Brown4f86d3a2007-10-03 18:58:00 -040042#include <linux/cpuidle.h>
Russell Kingba84be22009-01-06 14:41:07 -080043#include <linux/irqflags.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070044
Thomas Gleixner34349332007-02-16 01:27:54 -080045/*
46 * Include the apic definitions for x86 to have the APIC timer related defines
47 * available also for UP (on SMP it gets magically included via linux/smp.h).
48 * asm/acpi.h is not an option, as it would require more include magic. Also
49 * creating an empty asm-ia64/apic.h would just trade pest vs. cholera.
50 */
51#ifdef CONFIG_X86
52#include <asm/apic.h>
53#endif
54
Linus Torvalds1da177e2005-04-16 15:20:36 -070055#include <asm/io.h>
56#include <asm/uaccess.h>
57
58#include <acpi/acpi_bus.h>
59#include <acpi/processor.h>
Zhao Yakuic1e3b372008-06-24 17:58:53 +080060#include <asm/processor.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070061
Len Browna192a952009-07-28 16:45:54 -040062#define PREFIX "ACPI: "
63
Linus Torvalds1da177e2005-04-16 15:20:36 -070064#define ACPI_PROCESSOR_CLASS "processor"
Linus Torvalds1da177e2005-04-16 15:20:36 -070065#define _COMPONENT ACPI_PROCESSOR_COMPONENT
Len Brownf52fd662007-02-12 22:42:12 -050066ACPI_MODULE_NAME("processor_idle");
Linus Torvalds1da177e2005-04-16 15:20:36 -070067#define ACPI_PROCESSOR_FILE_POWER "power"
Ingo Molnar2aa44d02007-08-23 15:18:02 +020068#define PM_TIMER_TICK_NS (1000000000ULL/PM_TIMER_FREQUENCY)
Len Brown4f86d3a2007-10-03 18:58:00 -040069#define C2_OVERHEAD 1 /* 1us */
70#define C3_OVERHEAD 1 /* 1us */
Len Brown4f86d3a2007-10-03 18:58:00 -040071#define PM_TIMER_TICKS_TO_US(p) (((p) * 1000)/(PM_TIMER_FREQUENCY/1000))
Linus Torvalds1da177e2005-04-16 15:20:36 -070072
Len Brown4f86d3a2007-10-03 18:58:00 -040073static unsigned int max_cstate __read_mostly = ACPI_PROCESSOR_MAX_POWER;
74module_param(max_cstate, uint, 0000);
Andreas Mohrb6835052006-04-27 05:25:00 -040075static unsigned int nocst __read_mostly;
Linus Torvalds1da177e2005-04-16 15:20:36 -070076module_param(nocst, uint, 0000);
Len Brownd3e7e992010-07-22 17:23:10 -040077static int bm_check_disable __read_mostly;
78module_param(bm_check_disable, uint, 0000);
Linus Torvalds1da177e2005-04-16 15:20:36 -070079
Len Brown25de5712007-12-14 00:24:15 -050080static unsigned int latency_factor __read_mostly = 2;
Len Brown4963f622007-12-13 23:50:45 -050081module_param(latency_factor, uint, 0644);
Linus Torvalds1da177e2005-04-16 15:20:36 -070082
83/*
84 * IBM ThinkPad R40e crashes mysteriously when going into C2 or C3.
85 * For now disable this. Probably a bug somewhere else.
86 *
87 * To skip this limit, boot/load with a large max_cstate limit.
88 */
Jeff Garzik18552562007-10-03 15:15:40 -040089static int set_max_cstate(const struct dmi_system_id *id)
Linus Torvalds1da177e2005-04-16 15:20:36 -070090{
91 if (max_cstate > ACPI_PROCESSOR_MAX_POWER)
92 return 0;
93
Len Brown3d356002005-08-03 00:22:52 -040094 printk(KERN_NOTICE PREFIX "%s detected - limiting to C%ld max_cstate."
Len Brown4be44fc2005-08-05 00:44:28 -040095 " Override with \"processor.max_cstate=%d\"\n", id->ident,
96 (long)id->driver_data, ACPI_PROCESSOR_MAX_POWER + 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -070097
Len Brown3d356002005-08-03 00:22:52 -040098 max_cstate = (long)id->driver_data;
Linus Torvalds1da177e2005-04-16 15:20:36 -070099
100 return 0;
101}
102
Ashok Raj7ded5682006-02-03 21:51:23 +0100103/* Actually this shouldn't be __cpuinitdata, would be better to fix the
104 callers to only run once -AK */
105static struct dmi_system_id __cpuinitdata processor_power_dmi_table[] = {
Thomas Rosner876c1842006-01-06 01:31:00 -0500106 { set_max_cstate, "Clevo 5600D", {
107 DMI_MATCH(DMI_BIOS_VENDOR,"Phoenix Technologies LTD"),
108 DMI_MATCH(DMI_BIOS_VERSION,"SHE845M0.86C.0013.D.0302131307")},
Len Brown4be44fc2005-08-05 00:44:28 -0400109 (void *)2},
Arjan van de Ven370d5cd2010-01-27 15:25:39 -0800110 { set_max_cstate, "Pavilion zv5000", {
111 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
112 DMI_MATCH(DMI_PRODUCT_NAME,"Pavilion zv5000 (DS502A#ABA)")},
113 (void *)1},
114 { set_max_cstate, "Asus L8400B", {
115 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
116 DMI_MATCH(DMI_PRODUCT_NAME,"L8400B series Notebook PC")},
117 (void *)1},
Linus Torvalds1da177e2005-04-16 15:20:36 -0700118 {},
119};
120
Len Brown4f86d3a2007-10-03 18:58:00 -0400121
venkatesh.pallipadi@intel.com2e906652008-01-31 17:35:03 -0800122/*
123 * Callers should disable interrupts before the call and enable
124 * interrupts after return.
125 */
Venkatesh Pallipadiddc081a2007-11-19 21:43:22 -0500126static void acpi_safe_halt(void)
127{
128 current_thread_info()->status &= ~TS_POLLING;
129 /*
130 * TS_POLLING-cleared state must be visible before we
131 * test NEED_RESCHED:
132 */
133 smp_mb();
Venki Pallipadi71e93d12008-03-13 17:18:19 -0700134 if (!need_resched()) {
Venkatesh Pallipadiddc081a2007-11-19 21:43:22 -0500135 safe_halt();
Venki Pallipadi71e93d12008-03-13 17:18:19 -0700136 local_irq_disable();
137 }
Venkatesh Pallipadiddc081a2007-11-19 21:43:22 -0500138 current_thread_info()->status |= TS_POLLING;
139}
140
Thomas Gleixner169a0ab2007-02-16 01:27:55 -0800141#ifdef ARCH_APICTIMER_STOPS_ON_C3
142
143/*
144 * Some BIOS implementations switch to C3 in the published C2 state.
Linus Torvalds296d93c2007-03-23 08:03:47 -0700145 * This seems to be a common problem on AMD boxen, but other vendors
146 * are affected too. We pick the most conservative approach: we assume
147 * that the local APIC stops in both C2 and C3.
Thomas Gleixner169a0ab2007-02-16 01:27:55 -0800148 */
Len Brown7e275cc2009-05-15 02:08:44 -0400149static void lapic_timer_check_state(int state, struct acpi_processor *pr,
Thomas Gleixner169a0ab2007-02-16 01:27:55 -0800150 struct acpi_processor_cx *cx)
151{
152 struct acpi_processor_power *pwr = &pr->power;
Thomas Gleixnere585bef2007-03-23 16:08:01 +0100153 u8 type = local_apic_timer_c2_ok ? ACPI_STATE_C3 : ACPI_STATE_C2;
Thomas Gleixner169a0ab2007-02-16 01:27:55 -0800154
Venkatesh Pallipadidb954b52009-04-06 18:51:29 -0700155 if (cpu_has(&cpu_data(pr->id), X86_FEATURE_ARAT))
156 return;
157
Shaohua Li87ad57ba2009-05-19 16:09:42 +0800158 if (boot_cpu_has(X86_FEATURE_AMDC1E))
159 type = ACPI_STATE_C1;
160
Thomas Gleixner169a0ab2007-02-16 01:27:55 -0800161 /*
162 * Check, if one of the previous states already marked the lapic
163 * unstable
164 */
165 if (pwr->timer_broadcast_on_state < state)
166 return;
167
Thomas Gleixnere585bef2007-03-23 16:08:01 +0100168 if (cx->type >= type)
Linus Torvalds296d93c2007-03-23 08:03:47 -0700169 pr->power.timer_broadcast_on_state = state;
Thomas Gleixner169a0ab2007-02-16 01:27:55 -0800170}
171
Hidetoshi Seto918aae42009-12-14 17:10:06 +0900172static void __lapic_timer_propagate_broadcast(void *arg)
Thomas Gleixner169a0ab2007-02-16 01:27:55 -0800173{
Suresh Siddhaf833bab2009-08-17 14:34:59 -0700174 struct acpi_processor *pr = (struct acpi_processor *) arg;
Thomas Gleixnere9e2cdb2007-02-16 01:28:04 -0800175 unsigned long reason;
176
177 reason = pr->power.timer_broadcast_on_state < INT_MAX ?
178 CLOCK_EVT_NOTIFY_BROADCAST_ON : CLOCK_EVT_NOTIFY_BROADCAST_OFF;
179
180 clockevents_notify(reason, &pr->id);
Thomas Gleixnere9e2cdb2007-02-16 01:28:04 -0800181}
182
Hidetoshi Seto918aae42009-12-14 17:10:06 +0900183static void lapic_timer_propagate_broadcast(struct acpi_processor *pr)
184{
185 smp_call_function_single(pr->id, __lapic_timer_propagate_broadcast,
186 (void *)pr, 1);
187}
188
Thomas Gleixnere9e2cdb2007-02-16 01:28:04 -0800189/* Power(C) State timer broadcast control */
Len Brown7e275cc2009-05-15 02:08:44 -0400190static void lapic_timer_state_broadcast(struct acpi_processor *pr,
Thomas Gleixnere9e2cdb2007-02-16 01:28:04 -0800191 struct acpi_processor_cx *cx,
192 int broadcast)
193{
Thomas Gleixnere9e2cdb2007-02-16 01:28:04 -0800194 int state = cx - pr->power.states;
195
196 if (state >= pr->power.timer_broadcast_on_state) {
197 unsigned long reason;
198
199 reason = broadcast ? CLOCK_EVT_NOTIFY_BROADCAST_ENTER :
200 CLOCK_EVT_NOTIFY_BROADCAST_EXIT;
201 clockevents_notify(reason, &pr->id);
202 }
Thomas Gleixner169a0ab2007-02-16 01:27:55 -0800203}
204
205#else
206
Len Brown7e275cc2009-05-15 02:08:44 -0400207static void lapic_timer_check_state(int state, struct acpi_processor *pr,
Thomas Gleixner169a0ab2007-02-16 01:27:55 -0800208 struct acpi_processor_cx *cstate) { }
Len Brown7e275cc2009-05-15 02:08:44 -0400209static void lapic_timer_propagate_broadcast(struct acpi_processor *pr) { }
210static void lapic_timer_state_broadcast(struct acpi_processor *pr,
Thomas Gleixnere9e2cdb2007-02-16 01:28:04 -0800211 struct acpi_processor_cx *cx,
212 int broadcast)
213{
214}
Thomas Gleixner169a0ab2007-02-16 01:27:55 -0800215
216#endif
217
Thomas Gleixnerb04e7bd2007-09-22 22:29:05 +0000218/*
219 * Suspend / resume control
220 */
221static int acpi_idle_suspend;
Len Brown815ab0f2009-05-07 22:19:45 -0400222static u32 saved_bm_rld;
223
224static void acpi_idle_bm_rld_save(void)
225{
226 acpi_read_bit_register(ACPI_BITREG_BUS_MASTER_RLD, &saved_bm_rld);
227}
228static void acpi_idle_bm_rld_restore(void)
229{
230 u32 resumed_bm_rld;
231
232 acpi_read_bit_register(ACPI_BITREG_BUS_MASTER_RLD, &resumed_bm_rld);
233
234 if (resumed_bm_rld != saved_bm_rld)
235 acpi_write_bit_register(ACPI_BITREG_BUS_MASTER_RLD, saved_bm_rld);
236}
Thomas Gleixnerb04e7bd2007-09-22 22:29:05 +0000237
238int acpi_processor_suspend(struct acpi_device * device, pm_message_t state)
239{
Len Brown815ab0f2009-05-07 22:19:45 -0400240 if (acpi_idle_suspend == 1)
241 return 0;
242
243 acpi_idle_bm_rld_save();
Thomas Gleixnerb04e7bd2007-09-22 22:29:05 +0000244 acpi_idle_suspend = 1;
245 return 0;
246}
247
248int acpi_processor_resume(struct acpi_device * device)
249{
Len Brown815ab0f2009-05-07 22:19:45 -0400250 if (acpi_idle_suspend == 0)
251 return 0;
252
253 acpi_idle_bm_rld_restore();
Thomas Gleixnerb04e7bd2007-09-22 22:29:05 +0000254 acpi_idle_suspend = 0;
255 return 0;
256}
257
Pavel Machek61331162008-02-19 11:00:29 +0100258#if defined (CONFIG_GENERIC_TIME) && defined (CONFIG_X86)
Len Brown520daf72009-05-14 17:27:38 -0400259static void tsc_check_state(int state)
Andi Kleenddb25f92008-01-30 13:32:41 +0100260{
261 switch (boot_cpu_data.x86_vendor) {
262 case X86_VENDOR_AMD:
Venki Pallipadi40fb1712008-11-17 16:11:37 -0800263 case X86_VENDOR_INTEL:
Andi Kleenddb25f92008-01-30 13:32:41 +0100264 /*
265 * AMD Fam10h TSC will tick in all
266 * C/P/S0/S1 states when this bit is set.
267 */
Venki Pallipadi40fb1712008-11-17 16:11:37 -0800268 if (boot_cpu_has(X86_FEATURE_NONSTOP_TSC))
Len Brown520daf72009-05-14 17:27:38 -0400269 return;
Venki Pallipadi40fb1712008-11-17 16:11:37 -0800270
Andi Kleenddb25f92008-01-30 13:32:41 +0100271 /*FALL THROUGH*/
Andi Kleenddb25f92008-01-30 13:32:41 +0100272 default:
Len Brown520daf72009-05-14 17:27:38 -0400273 /* TSC could halt in idle, so notify users */
274 if (state > ACPI_STATE_C1)
275 mark_tsc_unstable("TSC halts in idle");
Andi Kleenddb25f92008-01-30 13:32:41 +0100276 }
277}
Len Brown520daf72009-05-14 17:27:38 -0400278#else
279static void tsc_check_state(int state) { return; }
Andi Kleenddb25f92008-01-30 13:32:41 +0100280#endif
281
Len Brown4be44fc2005-08-05 00:44:28 -0400282static int acpi_processor_get_power_info_fadt(struct acpi_processor *pr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700283{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700284
285 if (!pr)
Patrick Mocheld550d982006-06-27 00:41:40 -0400286 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700287
288 if (!pr->pblk)
Patrick Mocheld550d982006-06-27 00:41:40 -0400289 return -ENODEV;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700290
Linus Torvalds1da177e2005-04-16 15:20:36 -0700291 /* if info is obtained from pblk/fadt, type equals state */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700292 pr->power.states[ACPI_STATE_C2].type = ACPI_STATE_C2;
293 pr->power.states[ACPI_STATE_C3].type = ACPI_STATE_C3;
294
Venkatesh Pallipadi4c033552005-09-15 12:20:00 -0400295#ifndef CONFIG_HOTPLUG_CPU
296 /*
297 * Check for P_LVL2_UP flag before entering C2 and above on
Len Brown4f86d3a2007-10-03 18:58:00 -0400298 * an SMP system.
Venkatesh Pallipadi4c033552005-09-15 12:20:00 -0400299 */
Alexey Starikovskiyad71860a2007-02-02 19:48:19 +0300300 if ((num_online_cpus() > 1) &&
Alexey Starikovskiycee324b2007-02-02 19:48:22 +0300301 !(acpi_gbl_FADT.flags & ACPI_FADT_C2_MP_SUPPORTED))
Patrick Mocheld550d982006-06-27 00:41:40 -0400302 return -ENODEV;
Venkatesh Pallipadi4c033552005-09-15 12:20:00 -0400303#endif
304
Linus Torvalds1da177e2005-04-16 15:20:36 -0700305 /* determine C2 and C3 address from pblk */
306 pr->power.states[ACPI_STATE_C2].address = pr->pblk + 4;
307 pr->power.states[ACPI_STATE_C3].address = pr->pblk + 5;
308
309 /* determine latencies from FADT */
Alexey Starikovskiycee324b2007-02-02 19:48:22 +0300310 pr->power.states[ACPI_STATE_C2].latency = acpi_gbl_FADT.C2latency;
311 pr->power.states[ACPI_STATE_C3].latency = acpi_gbl_FADT.C3latency;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700312
Len Brown5d76b6f2010-01-19 22:41:14 -0500313 /*
314 * FADT specified C2 latency must be less than or equal to
315 * 100 microseconds.
316 */
317 if (acpi_gbl_FADT.C2latency > ACPI_PROCESSOR_MAX_C2_LATENCY) {
318 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
319 "C2 latency too large [%d]\n", acpi_gbl_FADT.C2latency));
320 /* invalidate C2 */
321 pr->power.states[ACPI_STATE_C2].address = 0;
322 }
323
Len Browna6d72c12010-01-19 23:10:04 -0500324 /*
325 * FADT supplied C3 latency must be less than or equal to
326 * 1000 microseconds.
327 */
328 if (acpi_gbl_FADT.C3latency > ACPI_PROCESSOR_MAX_C3_LATENCY) {
329 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
330 "C3 latency too large [%d]\n", acpi_gbl_FADT.C3latency));
331 /* invalidate C3 */
332 pr->power.states[ACPI_STATE_C3].address = 0;
333 }
334
Linus Torvalds1da177e2005-04-16 15:20:36 -0700335 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
336 "lvl2[0x%08x] lvl3[0x%08x]\n",
337 pr->power.states[ACPI_STATE_C2].address,
338 pr->power.states[ACPI_STATE_C3].address));
339
Patrick Mocheld550d982006-06-27 00:41:40 -0400340 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700341}
342
Venkatesh Pallipadi991528d2006-09-25 16:28:13 -0700343static int acpi_processor_get_power_info_default(struct acpi_processor *pr)
Venkatesh Pallipadiacf05f42005-03-31 23:23:15 -0500344{
Venkatesh Pallipadi991528d2006-09-25 16:28:13 -0700345 if (!pr->power.states[ACPI_STATE_C1].valid) {
346 /* set the first C-State to C1 */
347 /* all processors need to support C1 */
348 pr->power.states[ACPI_STATE_C1].type = ACPI_STATE_C1;
349 pr->power.states[ACPI_STATE_C1].valid = 1;
Venkatesh Pallipadi0fda6b42008-04-09 21:31:46 -0400350 pr->power.states[ACPI_STATE_C1].entry_method = ACPI_CSTATE_HALT;
Venkatesh Pallipadi991528d2006-09-25 16:28:13 -0700351 }
352 /* the C0 state only exists as a filler in our array */
Venkatesh Pallipadiacf05f42005-03-31 23:23:15 -0500353 pr->power.states[ACPI_STATE_C0].valid = 1;
Patrick Mocheld550d982006-06-27 00:41:40 -0400354 return 0;
Venkatesh Pallipadiacf05f42005-03-31 23:23:15 -0500355}
356
Len Brown4be44fc2005-08-05 00:44:28 -0400357static int acpi_processor_get_power_info_cst(struct acpi_processor *pr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700358{
Len Brown4be44fc2005-08-05 00:44:28 -0400359 acpi_status status = 0;
Lin Ming439913f2010-01-28 10:53:19 +0800360 u64 count;
Janosch Machowinskicf824782005-08-20 08:02:00 -0400361 int current_count;
Len Brown4be44fc2005-08-05 00:44:28 -0400362 int i;
363 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
364 union acpi_object *cst;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700365
Linus Torvalds1da177e2005-04-16 15:20:36 -0700366
Linus Torvalds1da177e2005-04-16 15:20:36 -0700367 if (nocst)
Patrick Mocheld550d982006-06-27 00:41:40 -0400368 return -ENODEV;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700369
Venkatesh Pallipadi991528d2006-09-25 16:28:13 -0700370 current_count = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700371
372 status = acpi_evaluate_object(pr->handle, "_CST", NULL, &buffer);
373 if (ACPI_FAILURE(status)) {
374 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No _CST, giving up\n"));
Patrick Mocheld550d982006-06-27 00:41:40 -0400375 return -ENODEV;
Len Brown4be44fc2005-08-05 00:44:28 -0400376 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700377
Jan Engelhardt50dd0962006-10-01 00:28:50 +0200378 cst = buffer.pointer;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700379
380 /* There must be at least 2 elements */
381 if (!cst || (cst->type != ACPI_TYPE_PACKAGE) || cst->package.count < 2) {
Len Brown64684632006-06-26 23:41:38 -0400382 printk(KERN_ERR PREFIX "not enough elements in _CST\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700383 status = -EFAULT;
384 goto end;
385 }
386
387 count = cst->package.elements[0].integer.value;
388
389 /* Validate number of power states. */
390 if (count < 1 || count != cst->package.count - 1) {
Len Brown64684632006-06-26 23:41:38 -0400391 printk(KERN_ERR PREFIX "count given by _CST is not valid\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700392 status = -EFAULT;
393 goto end;
394 }
395
Linus Torvalds1da177e2005-04-16 15:20:36 -0700396 /* Tell driver that at least _CST is supported. */
397 pr->flags.has_cst = 1;
398
399 for (i = 1; i <= count; i++) {
400 union acpi_object *element;
401 union acpi_object *obj;
402 struct acpi_power_register *reg;
403 struct acpi_processor_cx cx;
404
405 memset(&cx, 0, sizeof(cx));
406
Jan Engelhardt50dd0962006-10-01 00:28:50 +0200407 element = &(cst->package.elements[i]);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700408 if (element->type != ACPI_TYPE_PACKAGE)
409 continue;
410
411 if (element->package.count != 4)
412 continue;
413
Jan Engelhardt50dd0962006-10-01 00:28:50 +0200414 obj = &(element->package.elements[0]);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700415
416 if (obj->type != ACPI_TYPE_BUFFER)
417 continue;
418
Len Brown4be44fc2005-08-05 00:44:28 -0400419 reg = (struct acpi_power_register *)obj->buffer.pointer;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700420
421 if (reg->space_id != ACPI_ADR_SPACE_SYSTEM_IO &&
Len Brown4be44fc2005-08-05 00:44:28 -0400422 (reg->space_id != ACPI_ADR_SPACE_FIXED_HARDWARE))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700423 continue;
424
Linus Torvalds1da177e2005-04-16 15:20:36 -0700425 /* There should be an easy way to extract an integer... */
Jan Engelhardt50dd0962006-10-01 00:28:50 +0200426 obj = &(element->package.elements[1]);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700427 if (obj->type != ACPI_TYPE_INTEGER)
428 continue;
429
430 cx.type = obj->integer.value;
Venkatesh Pallipadi991528d2006-09-25 16:28:13 -0700431 /*
432 * Some buggy BIOSes won't list C1 in _CST -
433 * Let acpi_processor_get_power_info_default() handle them later
434 */
435 if (i == 1 && cx.type != ACPI_STATE_C1)
436 current_count++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700437
Venkatesh Pallipadi991528d2006-09-25 16:28:13 -0700438 cx.address = reg->address;
439 cx.index = current_count + 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700440
venkatesh.pallipadi@intel.combc71bec2008-01-31 17:35:04 -0800441 cx.entry_method = ACPI_CSTATE_SYSTEMIO;
Venkatesh Pallipadi991528d2006-09-25 16:28:13 -0700442 if (reg->space_id == ACPI_ADR_SPACE_FIXED_HARDWARE) {
443 if (acpi_processor_ffh_cstate_probe
444 (pr->id, &cx, reg) == 0) {
venkatesh.pallipadi@intel.combc71bec2008-01-31 17:35:04 -0800445 cx.entry_method = ACPI_CSTATE_FFH;
446 } else if (cx.type == ACPI_STATE_C1) {
Venkatesh Pallipadi991528d2006-09-25 16:28:13 -0700447 /*
448 * C1 is a special case where FIXED_HARDWARE
449 * can be handled in non-MWAIT way as well.
450 * In that case, save this _CST entry info.
Venkatesh Pallipadi991528d2006-09-25 16:28:13 -0700451 * Otherwise, ignore this info and continue.
452 */
venkatesh.pallipadi@intel.combc71bec2008-01-31 17:35:04 -0800453 cx.entry_method = ACPI_CSTATE_HALT;
Venkatesh Pallipadi4fcb2fc2008-02-11 17:46:31 -0800454 snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI HLT");
venkatesh.pallipadi@intel.combc71bec2008-01-31 17:35:04 -0800455 } else {
Venkatesh Pallipadi991528d2006-09-25 16:28:13 -0700456 continue;
457 }
Zhao Yakuida5e09a2008-06-24 18:01:09 +0800458 if (cx.type == ACPI_STATE_C1 &&
459 (idle_halt || idle_nomwait)) {
Zhao Yakuic1e3b372008-06-24 17:58:53 +0800460 /*
461 * In most cases the C1 space_id obtained from
462 * _CST object is FIXED_HARDWARE access mode.
463 * But when the option of idle=halt is added,
464 * the entry_method type should be changed from
465 * CSTATE_FFH to CSTATE_HALT.
Zhao Yakuida5e09a2008-06-24 18:01:09 +0800466 * When the option of idle=nomwait is added,
467 * the C1 entry_method type should be
468 * CSTATE_HALT.
Zhao Yakuic1e3b372008-06-24 17:58:53 +0800469 */
470 cx.entry_method = ACPI_CSTATE_HALT;
471 snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI HLT");
472 }
Venkatesh Pallipadi4fcb2fc2008-02-11 17:46:31 -0800473 } else {
474 snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI IOPORT 0x%x",
475 cx.address);
Venkatesh Pallipadi991528d2006-09-25 16:28:13 -0700476 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700477
Venkatesh Pallipadi0fda6b42008-04-09 21:31:46 -0400478 if (cx.type == ACPI_STATE_C1) {
479 cx.valid = 1;
480 }
Venkatesh Pallipadi4fcb2fc2008-02-11 17:46:31 -0800481
Jan Engelhardt50dd0962006-10-01 00:28:50 +0200482 obj = &(element->package.elements[2]);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700483 if (obj->type != ACPI_TYPE_INTEGER)
484 continue;
485
486 cx.latency = obj->integer.value;
487
Jan Engelhardt50dd0962006-10-01 00:28:50 +0200488 obj = &(element->package.elements[3]);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700489 if (obj->type != ACPI_TYPE_INTEGER)
490 continue;
491
492 cx.power = obj->integer.value;
493
Janosch Machowinskicf824782005-08-20 08:02:00 -0400494 current_count++;
495 memcpy(&(pr->power.states[current_count]), &cx, sizeof(cx));
496
497 /*
498 * We support total ACPI_PROCESSOR_MAX_POWER - 1
499 * (From 1 through ACPI_PROCESSOR_MAX_POWER - 1)
500 */
501 if (current_count >= (ACPI_PROCESSOR_MAX_POWER - 1)) {
502 printk(KERN_WARNING
503 "Limiting number of power states to max (%d)\n",
504 ACPI_PROCESSOR_MAX_POWER);
505 printk(KERN_WARNING
506 "Please increase ACPI_PROCESSOR_MAX_POWER if needed.\n");
507 break;
508 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700509 }
510
Len Brown4be44fc2005-08-05 00:44:28 -0400511 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d power states\n",
Janosch Machowinskicf824782005-08-20 08:02:00 -0400512 current_count));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700513
514 /* Validate number of power states discovered */
Janosch Machowinskicf824782005-08-20 08:02:00 -0400515 if (current_count < 2)
Venkatesh Pallipadi6d93c642005-09-15 12:19:00 -0400516 status = -EFAULT;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700517
Len Brown4be44fc2005-08-05 00:44:28 -0400518 end:
Len Brown02438d82006-06-30 03:19:10 -0400519 kfree(buffer.pointer);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700520
Patrick Mocheld550d982006-06-27 00:41:40 -0400521 return status;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700522}
523
Len Brown4be44fc2005-08-05 00:44:28 -0400524static void acpi_processor_power_verify_c3(struct acpi_processor *pr,
525 struct acpi_processor_cx *cx)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700526{
Pallipadi, Venkateshee1ca482009-05-21 17:09:10 -0700527 static int bm_check_flag = -1;
528 static int bm_control_flag = -1;
Venkatesh Pallipadi02df8b92005-04-15 15:07:10 -0400529
Linus Torvalds1da177e2005-04-16 15:20:36 -0700530
531 if (!cx->address)
Patrick Mocheld550d982006-06-27 00:41:40 -0400532 return;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700533
534 /*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700535 * PIIX4 Erratum #18: We don't support C3 when Type-F (fast)
536 * DMA transfers are used by any ISA device to avoid livelock.
537 * Note that we could disable Type-F DMA (as recommended by
538 * the erratum), but this is known to disrupt certain ISA
539 * devices thus we take the conservative approach.
540 */
541 else if (errata.piix4.fdma) {
542 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
Len Brown4be44fc2005-08-05 00:44:28 -0400543 "C3 not supported on PIIX4 with Type-F DMA\n"));
Patrick Mocheld550d982006-06-27 00:41:40 -0400544 return;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700545 }
546
Venkatesh Pallipadi02df8b92005-04-15 15:07:10 -0400547 /* All the logic here assumes flags.bm_check is same across all CPUs */
Pallipadi, Venkateshee1ca482009-05-21 17:09:10 -0700548 if (bm_check_flag == -1) {
Venkatesh Pallipadi02df8b92005-04-15 15:07:10 -0400549 /* Determine whether bm_check is needed based on CPU */
550 acpi_processor_power_init_bm_check(&(pr->flags), pr->id);
551 bm_check_flag = pr->flags.bm_check;
Pallipadi, Venkateshee1ca482009-05-21 17:09:10 -0700552 bm_control_flag = pr->flags.bm_control;
Venkatesh Pallipadi02df8b92005-04-15 15:07:10 -0400553 } else {
554 pr->flags.bm_check = bm_check_flag;
Pallipadi, Venkateshee1ca482009-05-21 17:09:10 -0700555 pr->flags.bm_control = bm_control_flag;
Venkatesh Pallipadi02df8b92005-04-15 15:07:10 -0400556 }
557
558 if (pr->flags.bm_check) {
Venkatesh Pallipadi02df8b92005-04-15 15:07:10 -0400559 if (!pr->flags.bm_control) {
Venki Pallipadied3110e2007-07-31 12:04:31 -0700560 if (pr->flags.has_cst != 1) {
561 /* bus mastering control is necessary */
562 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
563 "C3 support requires BM control\n"));
564 return;
565 } else {
566 /* Here we enter C3 without bus mastering */
567 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
568 "C3 support without BM control\n"));
569 }
Venkatesh Pallipadi02df8b92005-04-15 15:07:10 -0400570 }
571 } else {
Venkatesh Pallipadi02df8b92005-04-15 15:07:10 -0400572 /*
573 * WBINVD should be set in fadt, for C3 state to be
574 * supported on when bm_check is not required.
575 */
Alexey Starikovskiycee324b2007-02-02 19:48:22 +0300576 if (!(acpi_gbl_FADT.flags & ACPI_FADT_WBINVD)) {
Venkatesh Pallipadi02df8b92005-04-15 15:07:10 -0400577 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
Len Brown4be44fc2005-08-05 00:44:28 -0400578 "Cache invalidation should work properly"
579 " for C3 to be enabled on SMP systems\n"));
Patrick Mocheld550d982006-06-27 00:41:40 -0400580 return;
Venkatesh Pallipadi02df8b92005-04-15 15:07:10 -0400581 }
Venkatesh Pallipadi02df8b92005-04-15 15:07:10 -0400582 }
583
Linus Torvalds1da177e2005-04-16 15:20:36 -0700584 /*
585 * Otherwise we've met all of our C3 requirements.
586 * Normalize the C3 latency to expidite policy. Enable
587 * checking of bus mastering status (bm_check) so we can
588 * use this in our C3 policy
589 */
590 cx->valid = 1;
Len Brown4f86d3a2007-10-03 18:58:00 -0400591
Len Brown4f86d3a2007-10-03 18:58:00 -0400592 cx->latency_ticks = cx->latency;
Len Brown31878dd2009-01-28 18:28:09 -0500593 /*
594 * On older chipsets, BM_RLD needs to be set
595 * in order for Bus Master activity to wake the
596 * system from C3. Newer chipsets handle DMA
597 * during C3 automatically and BM_RLD is a NOP.
598 * In either case, the proper way to
599 * handle BM_RLD is to set it and leave it set.
600 */
Bob Moore50ffba12009-02-23 15:02:07 +0800601 acpi_write_bit_register(ACPI_BITREG_BUS_MASTER_RLD, 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700602
Patrick Mocheld550d982006-06-27 00:41:40 -0400603 return;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700604}
605
Linus Torvalds1da177e2005-04-16 15:20:36 -0700606static int acpi_processor_power_verify(struct acpi_processor *pr)
607{
608 unsigned int i;
609 unsigned int working = 0;
Venkatesh Pallipadi6eb0a0f2006-01-11 22:44:21 +0100610
Thomas Gleixner169a0ab2007-02-16 01:27:55 -0800611 pr->power.timer_broadcast_on_state = INT_MAX;
Venkatesh Pallipadi6eb0a0f2006-01-11 22:44:21 +0100612
Len Browna0bf2842009-05-15 01:29:31 -0400613 for (i = 1; i < ACPI_PROCESSOR_MAX_POWER && i <= max_cstate; i++) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700614 struct acpi_processor_cx *cx = &pr->power.states[i];
615
616 switch (cx->type) {
617 case ACPI_STATE_C1:
618 cx->valid = 1;
619 break;
620
621 case ACPI_STATE_C2:
Len Brownd22edd22010-01-19 23:29:09 -0500622 if (!cx->address)
623 break;
624 cx->valid = 1;
625 cx->latency_ticks = cx->latency; /* Normalize latency */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700626 break;
627
628 case ACPI_STATE_C3:
629 acpi_processor_power_verify_c3(pr, cx);
630 break;
631 }
Len Brown7e275cc2009-05-15 02:08:44 -0400632 if (!cx->valid)
633 continue;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700634
Len Brown7e275cc2009-05-15 02:08:44 -0400635 lapic_timer_check_state(i, pr, cx);
636 tsc_check_state(cx->type);
637 working++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700638 }
639
Hidetoshi Seto918aae42009-12-14 17:10:06 +0900640 lapic_timer_propagate_broadcast(pr);
Andi Kleenbd663342006-03-25 16:31:07 +0100641
Linus Torvalds1da177e2005-04-16 15:20:36 -0700642 return (working);
643}
644
Len Brown4be44fc2005-08-05 00:44:28 -0400645static int acpi_processor_get_power_info(struct acpi_processor *pr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700646{
647 unsigned int i;
648 int result;
649
Linus Torvalds1da177e2005-04-16 15:20:36 -0700650
651 /* NOTE: the idle thread may not be running while calling
652 * this function */
653
Venkatesh Pallipadi991528d2006-09-25 16:28:13 -0700654 /* Zero initialize all the C-states info. */
655 memset(pr->power.states, 0, sizeof(pr->power.states));
656
Linus Torvalds1da177e2005-04-16 15:20:36 -0700657 result = acpi_processor_get_power_info_cst(pr);
Venkatesh Pallipadi6d93c642005-09-15 12:19:00 -0400658 if (result == -ENODEV)
Darrick J. Wongc5a114f2006-10-19 23:28:28 -0700659 result = acpi_processor_get_power_info_fadt(pr);
Venkatesh Pallipadi6d93c642005-09-15 12:19:00 -0400660
Venkatesh Pallipadi991528d2006-09-25 16:28:13 -0700661 if (result)
662 return result;
663
664 acpi_processor_get_power_info_default(pr);
665
Janosch Machowinskicf824782005-08-20 08:02:00 -0400666 pr->power.count = acpi_processor_power_verify(pr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700667
Linus Torvalds1da177e2005-04-16 15:20:36 -0700668 /*
669 * if one state of type C2 or C3 is available, mark this
670 * CPU as being "idle manageable"
671 */
672 for (i = 1; i < ACPI_PROCESSOR_MAX_POWER; i++) {
Venkatesh Pallipadiacf05f42005-03-31 23:23:15 -0500673 if (pr->power.states[i].valid) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700674 pr->power.count = i;
Linus Torvalds2203d6e2005-11-18 07:29:51 -0800675 if (pr->power.states[i].type >= ACPI_STATE_C2)
676 pr->flags.power = 1;
Venkatesh Pallipadiacf05f42005-03-31 23:23:15 -0500677 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700678 }
679
Patrick Mocheld550d982006-06-27 00:41:40 -0400680 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700681}
682
Len Brown4f86d3a2007-10-03 18:58:00 -0400683/**
684 * acpi_idle_bm_check - checks if bus master activity was detected
685 */
686static int acpi_idle_bm_check(void)
687{
688 u32 bm_status = 0;
689
Len Brownd3e7e992010-07-22 17:23:10 -0400690 if (bm_check_disable)
691 return 0;
692
Bob Moore50ffba12009-02-23 15:02:07 +0800693 acpi_read_bit_register(ACPI_BITREG_BUS_MASTER_STATUS, &bm_status);
Len Brown4f86d3a2007-10-03 18:58:00 -0400694 if (bm_status)
Bob Moore50ffba12009-02-23 15:02:07 +0800695 acpi_write_bit_register(ACPI_BITREG_BUS_MASTER_STATUS, 1);
Len Brown4f86d3a2007-10-03 18:58:00 -0400696 /*
697 * PIIX4 Erratum #18: Note that BM_STS doesn't always reflect
698 * the true state of bus mastering activity; forcing us to
699 * manually check the BMIDEA bit of each IDE channel.
700 */
701 else if (errata.piix4.bmisx) {
702 if ((inb_p(errata.piix4.bmisx + 0x02) & 0x01)
703 || (inb_p(errata.piix4.bmisx + 0x0A) & 0x01))
704 bm_status = 1;
705 }
706 return bm_status;
707}
708
709/**
Len Brown4f86d3a2007-10-03 18:58:00 -0400710 * acpi_idle_do_entry - a helper function that does C2 and C3 type entry
711 * @cx: cstate data
venkatesh.pallipadi@intel.combc71bec2008-01-31 17:35:04 -0800712 *
713 * Caller disables interrupt before call and enables interrupt after return.
Len Brown4f86d3a2007-10-03 18:58:00 -0400714 */
715static inline void acpi_idle_do_entry(struct acpi_processor_cx *cx)
716{
Steven Rostedtdcf309972008-07-25 18:00:42 -0400717 /* Don't trace irqs off for idle */
718 stop_critical_timings();
venkatesh.pallipadi@intel.combc71bec2008-01-31 17:35:04 -0800719 if (cx->entry_method == ACPI_CSTATE_FFH) {
Len Brown4f86d3a2007-10-03 18:58:00 -0400720 /* Call into architectural FFH based C-state */
721 acpi_processor_ffh_cstate_enter(cx);
venkatesh.pallipadi@intel.combc71bec2008-01-31 17:35:04 -0800722 } else if (cx->entry_method == ACPI_CSTATE_HALT) {
723 acpi_safe_halt();
Len Brown4f86d3a2007-10-03 18:58:00 -0400724 } else {
Len Brown4f86d3a2007-10-03 18:58:00 -0400725 /* IO port based C-state */
726 inb(cx->address);
727 /* Dummy wait op - must do something useless after P_LVL2 read
728 because chipsets cannot guarantee that STPCLK# signal
729 gets asserted in time to freeze execution properly. */
Andi Kleencfa806f2010-07-20 15:18:36 -0700730 inl(acpi_gbl_FADT.xpm_timer_block.address);
Len Brown4f86d3a2007-10-03 18:58:00 -0400731 }
Steven Rostedtdcf309972008-07-25 18:00:42 -0400732 start_critical_timings();
Len Brown4f86d3a2007-10-03 18:58:00 -0400733}
734
735/**
736 * acpi_idle_enter_c1 - enters an ACPI C1 state-type
737 * @dev: the target CPU
738 * @state: the state data
739 *
740 * This is equivalent to the HALT instruction.
741 */
742static int acpi_idle_enter_c1(struct cpuidle_device *dev,
743 struct cpuidle_state *state)
744{
alex.shiff69f2b2009-03-04 11:55:26 -0800745 ktime_t kt1, kt2;
746 s64 idle_time;
Len Brown4f86d3a2007-10-03 18:58:00 -0400747 struct acpi_processor *pr;
748 struct acpi_processor_cx *cx = cpuidle_get_statedata(state);
venkatesh.pallipadi@intel.com9b12e182008-01-31 17:35:05 -0800749
Mike Travis706546d2008-06-09 16:22:23 -0700750 pr = __get_cpu_var(processors);
Len Brown4f86d3a2007-10-03 18:58:00 -0400751
752 if (unlikely(!pr))
753 return 0;
754
venkatesh.pallipadi@intel.com2e906652008-01-31 17:35:03 -0800755 local_irq_disable();
Venkatesh Pallipadib077fba2008-02-11 15:20:27 -0800756
757 /* Do not access any ACPI IO ports in suspend path */
758 if (acpi_idle_suspend) {
Venkatesh Pallipadib077fba2008-02-11 15:20:27 -0800759 local_irq_enable();
Shaohua Li7d60e8a2009-05-19 16:09:54 +0800760 cpu_relax();
Venkatesh Pallipadib077fba2008-02-11 15:20:27 -0800761 return 0;
762 }
763
Len Brown7e275cc2009-05-15 02:08:44 -0400764 lapic_timer_state_broadcast(pr, cx, 1);
alex.shiff69f2b2009-03-04 11:55:26 -0800765 kt1 = ktime_get_real();
venkatesh.pallipadi@intel.combc71bec2008-01-31 17:35:04 -0800766 acpi_idle_do_entry(cx);
alex.shiff69f2b2009-03-04 11:55:26 -0800767 kt2 = ktime_get_real();
768 idle_time = ktime_to_us(ktime_sub(kt2, kt1));
Len Brown4f86d3a2007-10-03 18:58:00 -0400769
venkatesh.pallipadi@intel.com2e906652008-01-31 17:35:03 -0800770 local_irq_enable();
Len Brown4f86d3a2007-10-03 18:58:00 -0400771 cx->usage++;
Len Brown7e275cc2009-05-15 02:08:44 -0400772 lapic_timer_state_broadcast(pr, cx, 0);
Len Brown4f86d3a2007-10-03 18:58:00 -0400773
alex.shiff69f2b2009-03-04 11:55:26 -0800774 return idle_time;
Len Brown4f86d3a2007-10-03 18:58:00 -0400775}
776
777/**
778 * acpi_idle_enter_simple - enters an ACPI state without BM handling
779 * @dev: the target CPU
780 * @state: the state data
781 */
782static int acpi_idle_enter_simple(struct cpuidle_device *dev,
783 struct cpuidle_state *state)
784{
785 struct acpi_processor *pr;
786 struct acpi_processor_cx *cx = cpuidle_get_statedata(state);
alex.shiff69f2b2009-03-04 11:55:26 -0800787 ktime_t kt1, kt2;
Venkatesh Pallipadi2da513f2010-04-22 16:48:33 -0700788 s64 idle_time_ns;
alex.shiff69f2b2009-03-04 11:55:26 -0800789 s64 idle_time;
Venkatesh Pallipadi50629112007-11-19 19:49:00 -0500790
Mike Travis706546d2008-06-09 16:22:23 -0700791 pr = __get_cpu_var(processors);
Len Brown4f86d3a2007-10-03 18:58:00 -0400792
793 if (unlikely(!pr))
794 return 0;
795
Len Browne1964412007-10-04 01:23:47 -0400796 if (acpi_idle_suspend)
797 return(acpi_idle_enter_c1(dev, state));
798
Len Brown4f86d3a2007-10-03 18:58:00 -0400799 local_irq_disable();
Len Brown02cf4f92010-05-24 14:27:44 -0400800
Pallipadi, Venkateshd306ebc2010-02-10 10:35:31 -0800801 if (cx->entry_method != ACPI_CSTATE_FFH) {
802 current_thread_info()->status &= ~TS_POLLING;
803 /*
804 * TS_POLLING-cleared state must be visible before we test
805 * NEED_RESCHED:
806 */
807 smp_mb();
Len Brown4f86d3a2007-10-03 18:58:00 -0400808
Len Brown02cf4f92010-05-24 14:27:44 -0400809 if (unlikely(need_resched())) {
810 current_thread_info()->status |= TS_POLLING;
811 local_irq_enable();
812 return 0;
813 }
Len Brown4f86d3a2007-10-03 18:58:00 -0400814 }
815
Thomas Gleixnere17bcb42007-12-07 19:16:17 +0100816 /*
817 * Must be done before busmaster disable as we might need to
818 * access HPET !
819 */
Len Brown7e275cc2009-05-15 02:08:44 -0400820 lapic_timer_state_broadcast(pr, cx, 1);
Thomas Gleixnere17bcb42007-12-07 19:16:17 +0100821
Len Brown4f86d3a2007-10-03 18:58:00 -0400822 if (cx->type == ACPI_STATE_C3)
823 ACPI_FLUSH_CPU_CACHE();
824
alex.shiff69f2b2009-03-04 11:55:26 -0800825 kt1 = ktime_get_real();
Venkatesh Pallipadi50629112007-11-19 19:49:00 -0500826 /* Tell the scheduler that we are going deep-idle: */
827 sched_clock_idle_sleep_event();
Len Brown4f86d3a2007-10-03 18:58:00 -0400828 acpi_idle_do_entry(cx);
alex.shiff69f2b2009-03-04 11:55:26 -0800829 kt2 = ktime_get_real();
Venkatesh Pallipadi2da513f2010-04-22 16:48:33 -0700830 idle_time_ns = ktime_to_ns(ktime_sub(kt2, kt1));
831 idle_time = idle_time_ns;
832 do_div(idle_time, NSEC_PER_USEC);
Len Brown4f86d3a2007-10-03 18:58:00 -0400833
Venkatesh Pallipadi50629112007-11-19 19:49:00 -0500834 /* Tell the scheduler how much we idled: */
Venkatesh Pallipadi2da513f2010-04-22 16:48:33 -0700835 sched_clock_idle_wakeup_event(idle_time_ns);
Len Brown4f86d3a2007-10-03 18:58:00 -0400836
837 local_irq_enable();
Len Brown02cf4f92010-05-24 14:27:44 -0400838 if (cx->entry_method != ACPI_CSTATE_FFH)
839 current_thread_info()->status |= TS_POLLING;
Len Brown4f86d3a2007-10-03 18:58:00 -0400840
841 cx->usage++;
842
Len Brown7e275cc2009-05-15 02:08:44 -0400843 lapic_timer_state_broadcast(pr, cx, 0);
Venkatesh Pallipadibceefad2010-06-02 10:01:09 -0700844 cx->time += idle_time;
alex.shiff69f2b2009-03-04 11:55:26 -0800845 return idle_time;
Len Brown4f86d3a2007-10-03 18:58:00 -0400846}
847
848static int c3_cpu_count;
849static DEFINE_SPINLOCK(c3_lock);
850
851/**
852 * acpi_idle_enter_bm - enters C3 with proper BM handling
853 * @dev: the target CPU
854 * @state: the state data
855 *
856 * If BM is detected, the deepest non-C3 idle state is entered instead.
857 */
858static int acpi_idle_enter_bm(struct cpuidle_device *dev,
859 struct cpuidle_state *state)
860{
861 struct acpi_processor *pr;
862 struct acpi_processor_cx *cx = cpuidle_get_statedata(state);
alex.shiff69f2b2009-03-04 11:55:26 -0800863 ktime_t kt1, kt2;
Venkatesh Pallipadi2da513f2010-04-22 16:48:33 -0700864 s64 idle_time_ns;
alex.shiff69f2b2009-03-04 11:55:26 -0800865 s64 idle_time;
alex.shiff69f2b2009-03-04 11:55:26 -0800866
Venkatesh Pallipadi50629112007-11-19 19:49:00 -0500867
Mike Travis706546d2008-06-09 16:22:23 -0700868 pr = __get_cpu_var(processors);
Len Brown4f86d3a2007-10-03 18:58:00 -0400869
870 if (unlikely(!pr))
871 return 0;
872
Len Browne1964412007-10-04 01:23:47 -0400873 if (acpi_idle_suspend)
874 return(acpi_idle_enter_c1(dev, state));
875
Len Brown718be4a2010-07-22 16:54:27 -0400876 if (!cx->bm_sts_skip && acpi_idle_bm_check()) {
Venkatesh Pallipadiddc081a2007-11-19 21:43:22 -0500877 if (dev->safe_state) {
Venkatesh Pallipadiaddbad42008-09-29 15:24:28 -0700878 dev->last_state = dev->safe_state;
Venkatesh Pallipadiddc081a2007-11-19 21:43:22 -0500879 return dev->safe_state->enter(dev, dev->safe_state);
880 } else {
venkatesh.pallipadi@intel.com2e906652008-01-31 17:35:03 -0800881 local_irq_disable();
Venkatesh Pallipadiddc081a2007-11-19 21:43:22 -0500882 acpi_safe_halt();
venkatesh.pallipadi@intel.com2e906652008-01-31 17:35:03 -0800883 local_irq_enable();
Venkatesh Pallipadiddc081a2007-11-19 21:43:22 -0500884 return 0;
885 }
886 }
887
Len Brown4f86d3a2007-10-03 18:58:00 -0400888 local_irq_disable();
Len Brown02cf4f92010-05-24 14:27:44 -0400889
Pallipadi, Venkateshd306ebc2010-02-10 10:35:31 -0800890 if (cx->entry_method != ACPI_CSTATE_FFH) {
891 current_thread_info()->status &= ~TS_POLLING;
892 /*
893 * TS_POLLING-cleared state must be visible before we test
894 * NEED_RESCHED:
895 */
896 smp_mb();
Len Brown4f86d3a2007-10-03 18:58:00 -0400897
Len Brown02cf4f92010-05-24 14:27:44 -0400898 if (unlikely(need_resched())) {
899 current_thread_info()->status |= TS_POLLING;
900 local_irq_enable();
901 return 0;
902 }
Len Brown4f86d3a2007-10-03 18:58:00 -0400903 }
904
Venki Pallipadi996520c2008-03-24 14:24:10 -0700905 acpi_unlazy_tlb(smp_processor_id());
906
Venkatesh Pallipadi50629112007-11-19 19:49:00 -0500907 /* Tell the scheduler that we are going deep-idle: */
908 sched_clock_idle_sleep_event();
Len Brown4f86d3a2007-10-03 18:58:00 -0400909 /*
910 * Must be done before busmaster disable as we might need to
911 * access HPET !
912 */
Len Brown7e275cc2009-05-15 02:08:44 -0400913 lapic_timer_state_broadcast(pr, cx, 1);
Len Brown4f86d3a2007-10-03 18:58:00 -0400914
Len Brownf461dde2009-04-23 18:59:43 -0400915 kt1 = ktime_get_real();
Venkatesh Pallipadiddc081a2007-11-19 21:43:22 -0500916 /*
917 * disable bus master
918 * bm_check implies we need ARB_DIS
919 * !bm_check implies we need cache flush
920 * bm_control implies whether we can do ARB_DIS
921 *
922 * That leaves a case where bm_check is set and bm_control is
923 * not set. In that case we cannot do much, we enter C3
924 * without doing anything.
925 */
926 if (pr->flags.bm_check && pr->flags.bm_control) {
Len Brown4f86d3a2007-10-03 18:58:00 -0400927 spin_lock(&c3_lock);
928 c3_cpu_count++;
929 /* Disable bus master arbitration when all CPUs are in C3 */
930 if (c3_cpu_count == num_online_cpus())
Bob Moore50ffba12009-02-23 15:02:07 +0800931 acpi_write_bit_register(ACPI_BITREG_ARB_DISABLE, 1);
Len Brown4f86d3a2007-10-03 18:58:00 -0400932 spin_unlock(&c3_lock);
Venkatesh Pallipadiddc081a2007-11-19 21:43:22 -0500933 } else if (!pr->flags.bm_check) {
934 ACPI_FLUSH_CPU_CACHE();
935 }
Len Brown4f86d3a2007-10-03 18:58:00 -0400936
Venkatesh Pallipadiddc081a2007-11-19 21:43:22 -0500937 acpi_idle_do_entry(cx);
Len Brown4f86d3a2007-10-03 18:58:00 -0400938
Venkatesh Pallipadiddc081a2007-11-19 21:43:22 -0500939 /* Re-enable bus master arbitration */
940 if (pr->flags.bm_check && pr->flags.bm_control) {
Len Brown4f86d3a2007-10-03 18:58:00 -0400941 spin_lock(&c3_lock);
Bob Moore50ffba12009-02-23 15:02:07 +0800942 acpi_write_bit_register(ACPI_BITREG_ARB_DISABLE, 0);
Len Brown4f86d3a2007-10-03 18:58:00 -0400943 c3_cpu_count--;
944 spin_unlock(&c3_lock);
945 }
Len Brownf461dde2009-04-23 18:59:43 -0400946 kt2 = ktime_get_real();
Zhao Yakui157317b2010-06-02 11:04:09 +0800947 idle_time_ns = ktime_to_ns(ktime_sub(kt2, kt1));
Venkatesh Pallipadi2da513f2010-04-22 16:48:33 -0700948 idle_time = idle_time_ns;
949 do_div(idle_time, NSEC_PER_USEC);
Len Brown4f86d3a2007-10-03 18:58:00 -0400950
Venkatesh Pallipadi50629112007-11-19 19:49:00 -0500951 /* Tell the scheduler how much we idled: */
Venkatesh Pallipadi2da513f2010-04-22 16:48:33 -0700952 sched_clock_idle_wakeup_event(idle_time_ns);
Len Brown4f86d3a2007-10-03 18:58:00 -0400953
954 local_irq_enable();
Len Brown02cf4f92010-05-24 14:27:44 -0400955 if (cx->entry_method != ACPI_CSTATE_FFH)
956 current_thread_info()->status |= TS_POLLING;
Len Brown4f86d3a2007-10-03 18:58:00 -0400957
958 cx->usage++;
959
Len Brown7e275cc2009-05-15 02:08:44 -0400960 lapic_timer_state_broadcast(pr, cx, 0);
Venkatesh Pallipadibceefad2010-06-02 10:01:09 -0700961 cx->time += idle_time;
alex.shiff69f2b2009-03-04 11:55:26 -0800962 return idle_time;
Len Brown4f86d3a2007-10-03 18:58:00 -0400963}
964
965struct cpuidle_driver acpi_idle_driver = {
966 .name = "acpi_idle",
967 .owner = THIS_MODULE,
968};
969
970/**
971 * acpi_processor_setup_cpuidle - prepares and configures CPUIDLE
972 * @pr: the ACPI processor
973 */
974static int acpi_processor_setup_cpuidle(struct acpi_processor *pr)
975{
venkatesh.pallipadi@intel.com9a0b8412008-01-31 17:35:06 -0800976 int i, count = CPUIDLE_DRIVER_STATE_START;
Len Brown4f86d3a2007-10-03 18:58:00 -0400977 struct acpi_processor_cx *cx;
978 struct cpuidle_state *state;
979 struct cpuidle_device *dev = &pr->power.dev;
980
981 if (!pr->flags.power_setup_done)
982 return -EINVAL;
983
984 if (pr->flags.power == 0) {
985 return -EINVAL;
986 }
987
Venkatesh Pallipadidcb84f32008-05-19 19:09:27 -0400988 dev->cpu = pr->id;
Venkatesh Pallipadi4fcb2fc2008-02-11 17:46:31 -0800989 for (i = 0; i < CPUIDLE_STATE_MAX; i++) {
990 dev->states[i].name[0] = '\0';
991 dev->states[i].desc[0] = '\0';
992 }
993
Len Brown615dfd92009-04-23 23:21:29 -0400994 if (max_cstate == 0)
995 max_cstate = 1;
996
Len Brown4f86d3a2007-10-03 18:58:00 -0400997 for (i = 1; i < ACPI_PROCESSOR_MAX_POWER && i <= max_cstate; i++) {
998 cx = &pr->power.states[i];
999 state = &dev->states[count];
1000
1001 if (!cx->valid)
1002 continue;
1003
1004#ifdef CONFIG_HOTPLUG_CPU
1005 if ((cx->type != ACPI_STATE_C1) && (num_online_cpus() > 1) &&
1006 !pr->flags.has_cst &&
1007 !(acpi_gbl_FADT.flags & ACPI_FADT_C2_MP_SUPPORTED))
1008 continue;
1009#endif
1010 cpuidle_set_statedata(state, cx);
1011
1012 snprintf(state->name, CPUIDLE_NAME_LEN, "C%d", i);
Venkatesh Pallipadi4fcb2fc2008-02-11 17:46:31 -08001013 strncpy(state->desc, cx->desc, CPUIDLE_DESC_LEN);
Len Brown4f86d3a2007-10-03 18:58:00 -04001014 state->exit_latency = cx->latency;
Len Brown4963f622007-12-13 23:50:45 -05001015 state->target_residency = cx->latency * latency_factor;
Len Brown4f86d3a2007-10-03 18:58:00 -04001016 state->power_usage = cx->power;
1017
1018 state->flags = 0;
1019 switch (cx->type) {
1020 case ACPI_STATE_C1:
1021 state->flags |= CPUIDLE_FLAG_SHALLOW;
Venki Pallipadi8e92b662008-02-29 10:24:32 -08001022 if (cx->entry_method == ACPI_CSTATE_FFH)
1023 state->flags |= CPUIDLE_FLAG_TIME_VALID;
1024
Len Brown4f86d3a2007-10-03 18:58:00 -04001025 state->enter = acpi_idle_enter_c1;
Venkatesh Pallipadiddc081a2007-11-19 21:43:22 -05001026 dev->safe_state = state;
Len Brown4f86d3a2007-10-03 18:58:00 -04001027 break;
1028
1029 case ACPI_STATE_C2:
1030 state->flags |= CPUIDLE_FLAG_BALANCED;
1031 state->flags |= CPUIDLE_FLAG_TIME_VALID;
1032 state->enter = acpi_idle_enter_simple;
Venkatesh Pallipadiddc081a2007-11-19 21:43:22 -05001033 dev->safe_state = state;
Len Brown4f86d3a2007-10-03 18:58:00 -04001034 break;
1035
1036 case ACPI_STATE_C3:
1037 state->flags |= CPUIDLE_FLAG_DEEP;
1038 state->flags |= CPUIDLE_FLAG_TIME_VALID;
1039 state->flags |= CPUIDLE_FLAG_CHECK_BM;
1040 state->enter = pr->flags.bm_check ?
1041 acpi_idle_enter_bm :
1042 acpi_idle_enter_simple;
1043 break;
1044 }
1045
1046 count++;
venkatesh.pallipadi@intel.com9a0b8412008-01-31 17:35:06 -08001047 if (count == CPUIDLE_STATE_MAX)
1048 break;
Len Brown4f86d3a2007-10-03 18:58:00 -04001049 }
1050
1051 dev->state_count = count;
1052
1053 if (!count)
1054 return -EINVAL;
1055
Len Brown4f86d3a2007-10-03 18:58:00 -04001056 return 0;
1057}
1058
1059int acpi_processor_cst_has_changed(struct acpi_processor *pr)
1060{
Venkatesh Pallipadidcb84f32008-05-19 19:09:27 -04001061 int ret = 0;
Len Brown4f86d3a2007-10-03 18:58:00 -04001062
Venkatesh Pallipadi36a91352008-04-30 13:57:15 -04001063 if (boot_option_idle_override)
1064 return 0;
1065
Len Brown4f86d3a2007-10-03 18:58:00 -04001066 if (!pr)
1067 return -EINVAL;
1068
1069 if (nocst) {
1070 return -ENODEV;
1071 }
1072
1073 if (!pr->flags.power_setup_done)
1074 return -ENODEV;
1075
1076 cpuidle_pause_and_lock();
1077 cpuidle_disable_device(&pr->power.dev);
1078 acpi_processor_get_power_info(pr);
Venkatesh Pallipadidcb84f32008-05-19 19:09:27 -04001079 if (pr->flags.power) {
1080 acpi_processor_setup_cpuidle(pr);
1081 ret = cpuidle_enable_device(&pr->power.dev);
1082 }
Len Brown4f86d3a2007-10-03 18:58:00 -04001083 cpuidle_resume_and_unlock();
1084
1085 return ret;
1086}
1087
Pierre Ossman7af8b662006-10-10 14:20:31 -07001088int __cpuinit acpi_processor_power_init(struct acpi_processor *pr,
Len Brown4be44fc2005-08-05 00:44:28 -04001089 struct acpi_device *device)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001090{
Len Brown4be44fc2005-08-05 00:44:28 -04001091 acpi_status status = 0;
Andreas Mohrb6835052006-04-27 05:25:00 -04001092 static int first_run;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001093
Venkatesh Pallipadi36a91352008-04-30 13:57:15 -04001094 if (boot_option_idle_override)
1095 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001096
1097 if (!first_run) {
Zhao Yakuic1e3b372008-06-24 17:58:53 +08001098 if (idle_halt) {
1099 /*
1100 * When the boot option of "idle=halt" is added, halt
1101 * is used for CPU IDLE.
1102 * In such case C2/C3 is meaningless. So the max_cstate
1103 * is set to one.
1104 */
1105 max_cstate = 1;
1106 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001107 dmi_check_system(processor_power_dmi_table);
Alexey Starikovskiyc1c30632007-11-26 20:42:19 +01001108 max_cstate = acpi_processor_cstate_check(max_cstate);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001109 if (max_cstate < ACPI_C_STATES_MAX)
Len Brown4be44fc2005-08-05 00:44:28 -04001110 printk(KERN_NOTICE
1111 "ACPI: processor limited to max C-state %d\n",
1112 max_cstate);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001113 first_run++;
1114 }
1115
Venkatesh Pallipadi02df8b92005-04-15 15:07:10 -04001116 if (!pr)
Patrick Mocheld550d982006-06-27 00:41:40 -04001117 return -EINVAL;
Venkatesh Pallipadi02df8b92005-04-15 15:07:10 -04001118
Alexey Starikovskiycee324b2007-02-02 19:48:22 +03001119 if (acpi_gbl_FADT.cst_control && !nocst) {
Len Brown4be44fc2005-08-05 00:44:28 -04001120 status =
Alexey Starikovskiycee324b2007-02-02 19:48:22 +03001121 acpi_os_write_port(acpi_gbl_FADT.smi_command, acpi_gbl_FADT.cst_control, 8);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001122 if (ACPI_FAILURE(status)) {
Thomas Renningera6fc6722006-06-26 23:58:43 -04001123 ACPI_EXCEPTION((AE_INFO, status,
1124 "Notifying BIOS of _CST ability failed"));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001125 }
1126 }
1127
Linus Torvalds1da177e2005-04-16 15:20:36 -07001128 acpi_processor_get_power_info(pr);
Len Brown4f86d3a2007-10-03 18:58:00 -04001129 pr->flags.power_setup_done = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001130
1131 /*
1132 * Install the idle handler if processor power management is supported.
1133 * Note that we use previously set idle handler will be used on
1134 * platforms that only support C1.
1135 */
Venkatesh Pallipadi36a91352008-04-30 13:57:15 -04001136 if (pr->flags.power) {
Len Brown4f86d3a2007-10-03 18:58:00 -04001137 acpi_processor_setup_cpuidle(pr);
Len Brown4f86d3a2007-10-03 18:58:00 -04001138 if (cpuidle_register_device(&pr->power.dev))
1139 return -EIO;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001140 }
Patrick Mocheld550d982006-06-27 00:41:40 -04001141 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001142}
1143
Len Brown4be44fc2005-08-05 00:44:28 -04001144int acpi_processor_power_exit(struct acpi_processor *pr,
1145 struct acpi_device *device)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001146{
Venkatesh Pallipadi36a91352008-04-30 13:57:15 -04001147 if (boot_option_idle_override)
1148 return 0;
1149
Venkatesh Pallipadidcb84f32008-05-19 19:09:27 -04001150 cpuidle_unregister_device(&pr->power.dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001151 pr->flags.power_setup_done = 0;
1152
Patrick Mocheld550d982006-06-27 00:41:40 -04001153 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001154}