blob: f95e7584d6e680bfe2b8cc49bc16f7c3a492a517 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * processor_thermal.c - Passive cooling submodule of the ACPI processor driver
3 *
4 * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
5 * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
6 * Copyright (C) 2004 Dominik Brodowski <linux@brodo.de>
7 * Copyright (C) 2004 Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
8 * - Added processor hotplug support
9 *
10 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
11 *
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License as published by
14 * the Free Software Foundation; either version 2 of the License, or (at
15 * your option) any later version.
16 *
17 * This program is distributed in the hope that it will be useful, but
18 * WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
20 * General Public License for more details.
21 *
22 * You should have received a copy of the GNU General Public License along
23 * with this program; if not, write to the Free Software Foundation, Inc.,
24 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
25 *
26 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
27 */
28
29#include <linux/kernel.h>
30#include <linux/module.h>
31#include <linux/init.h>
32#include <linux/cpufreq.h>
Lv Zheng8b484632013-12-03 08:49:16 +080033#include <linux/acpi.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070034#include <acpi/processor.h>
Lv Zheng8b484632013-12-03 08:49:16 +080035#include <asm/uaccess.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070036
Len Browna192a952009-07-28 16:45:54 -040037#define PREFIX "ACPI: "
38
Linus Torvalds1da177e2005-04-16 15:20:36 -070039#define ACPI_PROCESSOR_CLASS "processor"
Linus Torvalds1da177e2005-04-16 15:20:36 -070040#define _COMPONENT ACPI_PROCESSOR_COMPONENT
Len Brownf52fd662007-02-12 22:42:12 -050041ACPI_MODULE_NAME("processor_thermal");
Linus Torvalds1da177e2005-04-16 15:20:36 -070042
Linus Torvalds1da177e2005-04-16 15:20:36 -070043#ifdef CONFIG_CPU_FREQ
44
45/* If a passive cooling situation is detected, primarily CPUfreq is used, as it
46 * offers (in most cases) voltage scaling in addition to frequency scaling, and
47 * thus a cubic (instead of linear) reduction of energy. Also, we allow for
48 * _any_ cpufreq driver and not only the acpi-cpufreq driver.
49 */
50
Zhang Ruid9460fd222008-01-17 15:51:23 +080051#define CPUFREQ_THERMAL_MIN_STEP 0
52#define CPUFREQ_THERMAL_MAX_STEP 3
53
Mike Travisc938ac22008-03-05 08:31:29 -080054static DEFINE_PER_CPU(unsigned int, cpufreq_thermal_reduction_pctg);
Linus Torvalds1da177e2005-04-16 15:20:36 -070055static unsigned int acpi_thermal_cpufreq_is_init = 0;
56
Andi Kleen2815ab92012-02-06 08:17:11 -080057#define reduction_pctg(cpu) \
58 per_cpu(cpufreq_thermal_reduction_pctg, phys_package_first_cpu(cpu))
59
60/*
61 * Emulate "per package data" using per cpu data (which should really be
62 * provided elsewhere)
63 *
64 * Note we can lose a CPU on cpu hotunplug, in this case we forget the state
65 * temporarily. Fortunately that's not a big issue here (I hope)
66 */
67static int phys_package_first_cpu(int cpu)
68{
69 int i;
70 int id = topology_physical_package_id(cpu);
71
72 for_each_online_cpu(i)
73 if (topology_physical_package_id(i) == id)
74 return i;
75 return 0;
76}
77
Linus Torvalds1da177e2005-04-16 15:20:36 -070078static int cpu_has_cpufreq(unsigned int cpu)
79{
80 struct cpufreq_policy policy;
Thomas Renninger1cbf4c52004-09-16 11:07:00 -040081 if (!acpi_thermal_cpufreq_is_init || cpufreq_get_policy(&policy, cpu))
Thomas Renninger75b245b32005-12-21 01:29:00 -050082 return 0;
83 return 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -070084}
85
Len Brown4be44fc2005-08-05 00:44:28 -040086static int acpi_thermal_cpufreq_notifier(struct notifier_block *nb,
87 unsigned long event, void *data)
Linus Torvalds1da177e2005-04-16 15:20:36 -070088{
89 struct cpufreq_policy *policy = data;
90 unsigned long max_freq = 0;
91
92 if (event != CPUFREQ_ADJUST)
93 goto out;
94
Mike Travisc938ac22008-03-05 08:31:29 -080095 max_freq = (
96 policy->cpuinfo.max_freq *
Andi Kleen2815ab92012-02-06 08:17:11 -080097 (100 - reduction_pctg(policy->cpu) * 20)
Mike Travisc938ac22008-03-05 08:31:29 -080098 ) / 100;
Linus Torvalds1da177e2005-04-16 15:20:36 -070099
100 cpufreq_verify_within_limits(policy, 0, max_freq);
101
Len Brown4be44fc2005-08-05 00:44:28 -0400102 out:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700103 return 0;
104}
105
Linus Torvalds1da177e2005-04-16 15:20:36 -0700106static struct notifier_block acpi_thermal_cpufreq_notifier_block = {
107 .notifier_call = acpi_thermal_cpufreq_notifier,
108};
109
Zhang Ruid9460fd222008-01-17 15:51:23 +0800110static int cpufreq_get_max_state(unsigned int cpu)
111{
112 if (!cpu_has_cpufreq(cpu))
113 return 0;
114
115 return CPUFREQ_THERMAL_MAX_STEP;
116}
117
118static int cpufreq_get_cur_state(unsigned int cpu)
119{
120 if (!cpu_has_cpufreq(cpu))
121 return 0;
122
Andi Kleen2815ab92012-02-06 08:17:11 -0800123 return reduction_pctg(cpu);
Zhang Ruid9460fd222008-01-17 15:51:23 +0800124}
125
126static int cpufreq_set_cur_state(unsigned int cpu, int state)
127{
Andi Kleen2815ab92012-02-06 08:17:11 -0800128 int i;
129
Zhang Ruid9460fd222008-01-17 15:51:23 +0800130 if (!cpu_has_cpufreq(cpu))
131 return 0;
132
Andi Kleen2815ab92012-02-06 08:17:11 -0800133 reduction_pctg(cpu) = state;
134
135 /*
136 * Update all the CPUs in the same package because they all
137 * contribute to the temperature and often share the same
138 * frequency.
139 */
140 for_each_online_cpu(i) {
141 if (topology_physical_package_id(i) ==
142 topology_physical_package_id(cpu))
143 cpufreq_update_policy(i);
144 }
Zhang Ruid9460fd222008-01-17 15:51:23 +0800145 return 0;
146}
147
Len Brown4be44fc2005-08-05 00:44:28 -0400148void acpi_thermal_cpufreq_init(void)
149{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700150 int i;
151
Len Brown4be44fc2005-08-05 00:44:28 -0400152 i = cpufreq_register_notifier(&acpi_thermal_cpufreq_notifier_block,
153 CPUFREQ_POLICY_NOTIFIER);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700154 if (!i)
155 acpi_thermal_cpufreq_is_init = 1;
156}
157
Len Brown4be44fc2005-08-05 00:44:28 -0400158void acpi_thermal_cpufreq_exit(void)
159{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700160 if (acpi_thermal_cpufreq_is_init)
Len Brown4be44fc2005-08-05 00:44:28 -0400161 cpufreq_unregister_notifier
162 (&acpi_thermal_cpufreq_notifier_block,
163 CPUFREQ_POLICY_NOTIFIER);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700164
165 acpi_thermal_cpufreq_is_init = 0;
166}
167
Len Brown4be44fc2005-08-05 00:44:28 -0400168#else /* ! CONFIG_CPU_FREQ */
Zhang Ruid9460fd222008-01-17 15:51:23 +0800169static int cpufreq_get_max_state(unsigned int cpu)
170{
171 return 0;
172}
173
174static int cpufreq_get_cur_state(unsigned int cpu)
175{
176 return 0;
177}
178
179static int cpufreq_set_cur_state(unsigned int cpu, int state)
180{
181 return 0;
182}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700183
Linus Torvalds1da177e2005-04-16 15:20:36 -0700184#endif
185
Zhang Ruid9460fd222008-01-17 15:51:23 +0800186/* thermal coolign device callbacks */
187static int acpi_processor_max_state(struct acpi_processor *pr)
188{
189 int max_state = 0;
190
191 /*
192 * There exists four states according to
193 * cpufreq_thermal_reduction_ptg. 0, 1, 2, 3
194 */
195 max_state += cpufreq_get_max_state(pr->id);
196 if (pr->flags.throttling)
197 max_state += (pr->throttling.state_count -1);
198
199 return max_state;
200}
201static int
Matthew Garrett6503e5d2008-11-27 17:48:13 +0000202processor_get_max_state(struct thermal_cooling_device *cdev,
203 unsigned long *state)
Zhang Ruid9460fd222008-01-17 15:51:23 +0800204{
205 struct acpi_device *device = cdev->devdata;
Colin Ian King99aa3632013-03-25 10:50:06 +0000206 struct acpi_processor *pr;
Zhang Ruid9460fd222008-01-17 15:51:23 +0800207
Colin Ian King99aa3632013-03-25 10:50:06 +0000208 if (!device)
209 return -EINVAL;
210
211 pr = acpi_driver_data(device);
212 if (!pr)
Zhang Ruid9460fd222008-01-17 15:51:23 +0800213 return -EINVAL;
214
Matthew Garrett6503e5d2008-11-27 17:48:13 +0000215 *state = acpi_processor_max_state(pr);
216 return 0;
Zhang Ruid9460fd222008-01-17 15:51:23 +0800217}
218
219static int
Matthew Garrett6503e5d2008-11-27 17:48:13 +0000220processor_get_cur_state(struct thermal_cooling_device *cdev,
221 unsigned long *cur_state)
Zhang Ruid9460fd222008-01-17 15:51:23 +0800222{
223 struct acpi_device *device = cdev->devdata;
Colin Ian King99aa3632013-03-25 10:50:06 +0000224 struct acpi_processor *pr;
Zhang Ruid9460fd222008-01-17 15:51:23 +0800225
Colin Ian King99aa3632013-03-25 10:50:06 +0000226 if (!device)
227 return -EINVAL;
228
229 pr = acpi_driver_data(device);
230 if (!pr)
Zhang Ruid9460fd222008-01-17 15:51:23 +0800231 return -EINVAL;
232
Matthew Garrett6503e5d2008-11-27 17:48:13 +0000233 *cur_state = cpufreq_get_cur_state(pr->id);
Zhang Ruid9460fd222008-01-17 15:51:23 +0800234 if (pr->flags.throttling)
Matthew Garrett6503e5d2008-11-27 17:48:13 +0000235 *cur_state += pr->throttling.state;
236 return 0;
Zhang Ruid9460fd222008-01-17 15:51:23 +0800237}
238
239static int
Matthew Garrett6503e5d2008-11-27 17:48:13 +0000240processor_set_cur_state(struct thermal_cooling_device *cdev,
241 unsigned long state)
Zhang Ruid9460fd222008-01-17 15:51:23 +0800242{
243 struct acpi_device *device = cdev->devdata;
Colin Ian King99aa3632013-03-25 10:50:06 +0000244 struct acpi_processor *pr;
Zhang Ruid9460fd222008-01-17 15:51:23 +0800245 int result = 0;
246 int max_pstate;
247
Colin Ian King99aa3632013-03-25 10:50:06 +0000248 if (!device)
249 return -EINVAL;
250
251 pr = acpi_driver_data(device);
252 if (!pr)
Zhang Ruid9460fd222008-01-17 15:51:23 +0800253 return -EINVAL;
254
255 max_pstate = cpufreq_get_max_state(pr->id);
256
257 if (state > acpi_processor_max_state(pr))
258 return -EINVAL;
259
260 if (state <= max_pstate) {
261 if (pr->flags.throttling && pr->throttling.state)
Frans Pop2a908002009-08-26 14:29:29 -0700262 result = acpi_processor_set_throttling(pr, 0, false);
Zhang Ruid9460fd222008-01-17 15:51:23 +0800263 cpufreq_set_cur_state(pr->id, state);
264 } else {
265 cpufreq_set_cur_state(pr->id, max_pstate);
266 result = acpi_processor_set_throttling(pr,
Frans Pop2a908002009-08-26 14:29:29 -0700267 state - max_pstate, false);
Zhang Ruid9460fd222008-01-17 15:51:23 +0800268 }
269 return result;
270}
271
Vasiliy Kulikov9c8b04b2011-06-25 21:07:52 +0400272const struct thermal_cooling_device_ops processor_cooling_ops = {
Zhang Ruid9460fd222008-01-17 15:51:23 +0800273 .get_max_state = processor_get_max_state,
274 .get_cur_state = processor_get_cur_state,
275 .set_cur_state = processor_set_cur_state,
276};