Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
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> | |
1da177e4 LT |
33 | |
34 | #include <asm/uaccess.h> | |
35 | ||
36 | #include <acpi/acpi_bus.h> | |
37 | #include <acpi/processor.h> | |
38 | #include <acpi/acpi_drivers.h> | |
39 | ||
a192a958 LB |
40 | #define PREFIX "ACPI: " |
41 | ||
1da177e4 | 42 | #define ACPI_PROCESSOR_CLASS "processor" |
1da177e4 | 43 | #define _COMPONENT ACPI_PROCESSOR_COMPONENT |
f52fd66d | 44 | ACPI_MODULE_NAME("processor_thermal"); |
1da177e4 | 45 | |
1da177e4 LT |
46 | #ifdef CONFIG_CPU_FREQ |
47 | ||
48 | /* If a passive cooling situation is detected, primarily CPUfreq is used, as it | |
49 | * offers (in most cases) voltage scaling in addition to frequency scaling, and | |
50 | * thus a cubic (instead of linear) reduction of energy. Also, we allow for | |
51 | * _any_ cpufreq driver and not only the acpi-cpufreq driver. | |
52 | */ | |
53 | ||
d9460fd2 ZR |
54 | #define CPUFREQ_THERMAL_MIN_STEP 0 |
55 | #define CPUFREQ_THERMAL_MAX_STEP 3 | |
56 | ||
c938ac21 | 57 | static DEFINE_PER_CPU(unsigned int, cpufreq_thermal_reduction_pctg); |
1da177e4 LT |
58 | static unsigned int acpi_thermal_cpufreq_is_init = 0; |
59 | ||
2815ab92 AK |
60 | #define reduction_pctg(cpu) \ |
61 | per_cpu(cpufreq_thermal_reduction_pctg, phys_package_first_cpu(cpu)) | |
62 | ||
63 | /* | |
64 | * Emulate "per package data" using per cpu data (which should really be | |
65 | * provided elsewhere) | |
66 | * | |
67 | * Note we can lose a CPU on cpu hotunplug, in this case we forget the state | |
68 | * temporarily. Fortunately that's not a big issue here (I hope) | |
69 | */ | |
70 | static int phys_package_first_cpu(int cpu) | |
71 | { | |
72 | int i; | |
73 | int id = topology_physical_package_id(cpu); | |
74 | ||
75 | for_each_online_cpu(i) | |
76 | if (topology_physical_package_id(i) == id) | |
77 | return i; | |
78 | return 0; | |
79 | } | |
80 | ||
1da177e4 LT |
81 | static int cpu_has_cpufreq(unsigned int cpu) |
82 | { | |
83 | struct cpufreq_policy policy; | |
1cbf4c56 | 84 | if (!acpi_thermal_cpufreq_is_init || cpufreq_get_policy(&policy, cpu)) |
75b245b3 TR |
85 | return 0; |
86 | return 1; | |
1da177e4 LT |
87 | } |
88 | ||
4be44fcd LB |
89 | static int acpi_thermal_cpufreq_notifier(struct notifier_block *nb, |
90 | unsigned long event, void *data) | |
1da177e4 LT |
91 | { |
92 | struct cpufreq_policy *policy = data; | |
93 | unsigned long max_freq = 0; | |
94 | ||
95 | if (event != CPUFREQ_ADJUST) | |
96 | goto out; | |
97 | ||
c938ac21 MT |
98 | max_freq = ( |
99 | policy->cpuinfo.max_freq * | |
2815ab92 | 100 | (100 - reduction_pctg(policy->cpu) * 20) |
c938ac21 | 101 | ) / 100; |
1da177e4 LT |
102 | |
103 | cpufreq_verify_within_limits(policy, 0, max_freq); | |
104 | ||
4be44fcd | 105 | out: |
1da177e4 LT |
106 | return 0; |
107 | } | |
108 | ||
1da177e4 LT |
109 | static struct notifier_block acpi_thermal_cpufreq_notifier_block = { |
110 | .notifier_call = acpi_thermal_cpufreq_notifier, | |
111 | }; | |
112 | ||
d9460fd2 ZR |
113 | static int cpufreq_get_max_state(unsigned int cpu) |
114 | { | |
115 | if (!cpu_has_cpufreq(cpu)) | |
116 | return 0; | |
117 | ||
118 | return CPUFREQ_THERMAL_MAX_STEP; | |
119 | } | |
120 | ||
121 | static int cpufreq_get_cur_state(unsigned int cpu) | |
122 | { | |
123 | if (!cpu_has_cpufreq(cpu)) | |
124 | return 0; | |
125 | ||
2815ab92 | 126 | return reduction_pctg(cpu); |
d9460fd2 ZR |
127 | } |
128 | ||
129 | static int cpufreq_set_cur_state(unsigned int cpu, int state) | |
130 | { | |
2815ab92 AK |
131 | int i; |
132 | ||
d9460fd2 ZR |
133 | if (!cpu_has_cpufreq(cpu)) |
134 | return 0; | |
135 | ||
2815ab92 AK |
136 | reduction_pctg(cpu) = state; |
137 | ||
138 | /* | |
139 | * Update all the CPUs in the same package because they all | |
140 | * contribute to the temperature and often share the same | |
141 | * frequency. | |
142 | */ | |
143 | for_each_online_cpu(i) { | |
144 | if (topology_physical_package_id(i) == | |
145 | topology_physical_package_id(cpu)) | |
146 | cpufreq_update_policy(i); | |
147 | } | |
d9460fd2 ZR |
148 | return 0; |
149 | } | |
150 | ||
4be44fcd LB |
151 | void acpi_thermal_cpufreq_init(void) |
152 | { | |
1da177e4 LT |
153 | int i; |
154 | ||
4be44fcd LB |
155 | i = cpufreq_register_notifier(&acpi_thermal_cpufreq_notifier_block, |
156 | CPUFREQ_POLICY_NOTIFIER); | |
1da177e4 LT |
157 | if (!i) |
158 | acpi_thermal_cpufreq_is_init = 1; | |
159 | } | |
160 | ||
4be44fcd LB |
161 | void acpi_thermal_cpufreq_exit(void) |
162 | { | |
1da177e4 | 163 | if (acpi_thermal_cpufreq_is_init) |
4be44fcd LB |
164 | cpufreq_unregister_notifier |
165 | (&acpi_thermal_cpufreq_notifier_block, | |
166 | CPUFREQ_POLICY_NOTIFIER); | |
1da177e4 LT |
167 | |
168 | acpi_thermal_cpufreq_is_init = 0; | |
169 | } | |
170 | ||
4be44fcd | 171 | #else /* ! CONFIG_CPU_FREQ */ |
d9460fd2 ZR |
172 | static int cpufreq_get_max_state(unsigned int cpu) |
173 | { | |
174 | return 0; | |
175 | } | |
176 | ||
177 | static int cpufreq_get_cur_state(unsigned int cpu) | |
178 | { | |
179 | return 0; | |
180 | } | |
181 | ||
182 | static int cpufreq_set_cur_state(unsigned int cpu, int state) | |
183 | { | |
184 | return 0; | |
185 | } | |
1da177e4 | 186 | |
1da177e4 LT |
187 | #endif |
188 | ||
4be44fcd | 189 | int acpi_processor_get_limit_info(struct acpi_processor *pr) |
1da177e4 | 190 | { |
1da177e4 LT |
191 | |
192 | if (!pr) | |
d550d98d | 193 | return -EINVAL; |
1da177e4 LT |
194 | |
195 | if (pr->flags.throttling) | |
196 | pr->flags.limit = 1; | |
197 | ||
d550d98d | 198 | return 0; |
1da177e4 LT |
199 | } |
200 | ||
d9460fd2 ZR |
201 | /* thermal coolign device callbacks */ |
202 | static int acpi_processor_max_state(struct acpi_processor *pr) | |
203 | { | |
204 | int max_state = 0; | |
205 | ||
206 | /* | |
207 | * There exists four states according to | |
208 | * cpufreq_thermal_reduction_ptg. 0, 1, 2, 3 | |
209 | */ | |
210 | max_state += cpufreq_get_max_state(pr->id); | |
211 | if (pr->flags.throttling) | |
212 | max_state += (pr->throttling.state_count -1); | |
213 | ||
214 | return max_state; | |
215 | } | |
216 | static int | |
6503e5df MG |
217 | processor_get_max_state(struct thermal_cooling_device *cdev, |
218 | unsigned long *state) | |
d9460fd2 ZR |
219 | { |
220 | struct acpi_device *device = cdev->devdata; | |
99aa3638 | 221 | struct acpi_processor *pr; |
d9460fd2 | 222 | |
99aa3638 CIK |
223 | if (!device) |
224 | return -EINVAL; | |
225 | ||
226 | pr = acpi_driver_data(device); | |
227 | if (!pr) | |
d9460fd2 ZR |
228 | return -EINVAL; |
229 | ||
6503e5df MG |
230 | *state = acpi_processor_max_state(pr); |
231 | return 0; | |
d9460fd2 ZR |
232 | } |
233 | ||
234 | static int | |
6503e5df MG |
235 | processor_get_cur_state(struct thermal_cooling_device *cdev, |
236 | unsigned long *cur_state) | |
d9460fd2 ZR |
237 | { |
238 | struct acpi_device *device = cdev->devdata; | |
99aa3638 | 239 | struct acpi_processor *pr; |
d9460fd2 | 240 | |
99aa3638 CIK |
241 | if (!device) |
242 | return -EINVAL; | |
243 | ||
244 | pr = acpi_driver_data(device); | |
245 | if (!pr) | |
d9460fd2 ZR |
246 | return -EINVAL; |
247 | ||
6503e5df | 248 | *cur_state = cpufreq_get_cur_state(pr->id); |
d9460fd2 | 249 | if (pr->flags.throttling) |
6503e5df MG |
250 | *cur_state += pr->throttling.state; |
251 | return 0; | |
d9460fd2 ZR |
252 | } |
253 | ||
254 | static int | |
6503e5df MG |
255 | processor_set_cur_state(struct thermal_cooling_device *cdev, |
256 | unsigned long state) | |
d9460fd2 ZR |
257 | { |
258 | struct acpi_device *device = cdev->devdata; | |
99aa3638 | 259 | struct acpi_processor *pr; |
d9460fd2 ZR |
260 | int result = 0; |
261 | int max_pstate; | |
262 | ||
99aa3638 CIK |
263 | if (!device) |
264 | return -EINVAL; | |
265 | ||
266 | pr = acpi_driver_data(device); | |
267 | if (!pr) | |
d9460fd2 ZR |
268 | return -EINVAL; |
269 | ||
270 | max_pstate = cpufreq_get_max_state(pr->id); | |
271 | ||
272 | if (state > acpi_processor_max_state(pr)) | |
273 | return -EINVAL; | |
274 | ||
275 | if (state <= max_pstate) { | |
276 | if (pr->flags.throttling && pr->throttling.state) | |
2a908002 | 277 | result = acpi_processor_set_throttling(pr, 0, false); |
d9460fd2 ZR |
278 | cpufreq_set_cur_state(pr->id, state); |
279 | } else { | |
280 | cpufreq_set_cur_state(pr->id, max_pstate); | |
281 | result = acpi_processor_set_throttling(pr, | |
2a908002 | 282 | state - max_pstate, false); |
d9460fd2 ZR |
283 | } |
284 | return result; | |
285 | } | |
286 | ||
9c8b04be | 287 | const struct thermal_cooling_device_ops processor_cooling_ops = { |
d9460fd2 ZR |
288 | .get_max_state = processor_get_max_state, |
289 | .get_cur_state = processor_get_cur_state, | |
290 | .set_cur_state = processor_set_cur_state, | |
291 | }; |