Blame view
drivers/acpi/processor_thermal.c
6.45 KB
1da177e4c
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 |
/* * processor_thermal.c - Passive cooling submodule of the ACPI processor driver * * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com> * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com> * Copyright (C) 2004 Dominik Brodowski <linux@brodo.de> * Copyright (C) 2004 Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> * - Added processor hotplug support * * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or (at * your option) any later version. * * This program is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * |
1da177e4c
|
22 23 24 25 26 27 28 |
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */ #include <linux/kernel.h> #include <linux/module.h> #include <linux/init.h> #include <linux/cpufreq.h> |
8b48463f8
|
29 |
#include <linux/acpi.h> |
1da177e4c
|
30 |
#include <acpi/processor.h> |
8b48463f8
|
31 |
#include <asm/uaccess.h> |
1da177e4c
|
32 |
|
a192a9580
|
33 |
#define PREFIX "ACPI: " |
1da177e4c
|
34 |
#define ACPI_PROCESSOR_CLASS "processor" |
1da177e4c
|
35 |
#define _COMPONENT ACPI_PROCESSOR_COMPONENT |
f52fd66d2
|
36 |
ACPI_MODULE_NAME("processor_thermal"); |
1da177e4c
|
37 |
|
1da177e4c
|
38 39 40 41 42 43 44 |
#ifdef CONFIG_CPU_FREQ /* If a passive cooling situation is detected, primarily CPUfreq is used, as it * offers (in most cases) voltage scaling in addition to frequency scaling, and * thus a cubic (instead of linear) reduction of energy. Also, we allow for * _any_ cpufreq driver and not only the acpi-cpufreq driver. */ |
d9460fd22
|
45 46 |
#define CPUFREQ_THERMAL_MIN_STEP 0 #define CPUFREQ_THERMAL_MAX_STEP 3 |
c938ac213
|
47 |
static DEFINE_PER_CPU(unsigned int, cpufreq_thermal_reduction_pctg); |
1da177e4c
|
48 |
static unsigned int acpi_thermal_cpufreq_is_init = 0; |
2815ab92b
|
49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 |
#define reduction_pctg(cpu) \ per_cpu(cpufreq_thermal_reduction_pctg, phys_package_first_cpu(cpu)) /* * Emulate "per package data" using per cpu data (which should really be * provided elsewhere) * * Note we can lose a CPU on cpu hotunplug, in this case we forget the state * temporarily. Fortunately that's not a big issue here (I hope) */ static int phys_package_first_cpu(int cpu) { int i; int id = topology_physical_package_id(cpu); for_each_online_cpu(i) if (topology_physical_package_id(i) == id) return i; return 0; } |
1da177e4c
|
69 70 71 |
static int cpu_has_cpufreq(unsigned int cpu) { struct cpufreq_policy policy; |
1cbf4c563
|
72 |
if (!acpi_thermal_cpufreq_is_init || cpufreq_get_policy(&policy, cpu)) |
75b245b32
|
73 74 |
return 0; return 1; |
1da177e4c
|
75 |
} |
4be44fcd3
|
76 77 |
static int acpi_thermal_cpufreq_notifier(struct notifier_block *nb, unsigned long event, void *data) |
1da177e4c
|
78 79 80 81 82 83 |
{ struct cpufreq_policy *policy = data; unsigned long max_freq = 0; if (event != CPUFREQ_ADJUST) goto out; |
c938ac213
|
84 85 |
max_freq = ( policy->cpuinfo.max_freq * |
2815ab92b
|
86 |
(100 - reduction_pctg(policy->cpu) * 20) |
c938ac213
|
87 |
) / 100; |
1da177e4c
|
88 89 |
cpufreq_verify_within_limits(policy, 0, max_freq); |
4be44fcd3
|
90 |
out: |
1da177e4c
|
91 92 |
return 0; } |
1da177e4c
|
93 94 95 |
static struct notifier_block acpi_thermal_cpufreq_notifier_block = { .notifier_call = acpi_thermal_cpufreq_notifier, }; |
d9460fd22
|
96 97 98 99 100 101 102 103 104 105 106 107 |
static int cpufreq_get_max_state(unsigned int cpu) { if (!cpu_has_cpufreq(cpu)) return 0; return CPUFREQ_THERMAL_MAX_STEP; } static int cpufreq_get_cur_state(unsigned int cpu) { if (!cpu_has_cpufreq(cpu)) return 0; |
2815ab92b
|
108 |
return reduction_pctg(cpu); |
d9460fd22
|
109 110 111 112 |
} static int cpufreq_set_cur_state(unsigned int cpu, int state) { |
2815ab92b
|
113 |
int i; |
d9460fd22
|
114 115 |
if (!cpu_has_cpufreq(cpu)) return 0; |
2815ab92b
|
116 117 118 119 120 121 122 123 124 125 126 127 |
reduction_pctg(cpu) = state; /* * Update all the CPUs in the same package because they all * contribute to the temperature and often share the same * frequency. */ for_each_online_cpu(i) { if (topology_physical_package_id(i) == topology_physical_package_id(cpu)) cpufreq_update_policy(i); } |
d9460fd22
|
128 129 |
return 0; } |
4be44fcd3
|
130 131 |
void acpi_thermal_cpufreq_init(void) { |
1da177e4c
|
132 |
int i; |
4be44fcd3
|
133 134 |
i = cpufreq_register_notifier(&acpi_thermal_cpufreq_notifier_block, CPUFREQ_POLICY_NOTIFIER); |
1da177e4c
|
135 136 137 |
if (!i) acpi_thermal_cpufreq_is_init = 1; } |
4be44fcd3
|
138 139 |
void acpi_thermal_cpufreq_exit(void) { |
1da177e4c
|
140 |
if (acpi_thermal_cpufreq_is_init) |
4be44fcd3
|
141 142 143 |
cpufreq_unregister_notifier (&acpi_thermal_cpufreq_notifier_block, CPUFREQ_POLICY_NOTIFIER); |
1da177e4c
|
144 145 146 |
acpi_thermal_cpufreq_is_init = 0; } |
4be44fcd3
|
147 |
#else /* ! CONFIG_CPU_FREQ */ |
d9460fd22
|
148 149 150 151 152 153 154 155 156 157 158 159 160 161 |
static int cpufreq_get_max_state(unsigned int cpu) { return 0; } static int cpufreq_get_cur_state(unsigned int cpu) { return 0; } static int cpufreq_set_cur_state(unsigned int cpu, int state) { return 0; } |
1da177e4c
|
162 |
|
1da177e4c
|
163 |
#endif |
6dd7aca82
|
164 |
/* thermal cooling device callbacks */ |
d9460fd22
|
165 166 167 168 169 170 |
static int acpi_processor_max_state(struct acpi_processor *pr) { int max_state = 0; /* * There exists four states according to |
6dd7aca82
|
171 |
* cpufreq_thermal_reduction_pctg. 0, 1, 2, 3 |
d9460fd22
|
172 173 174 175 176 177 178 179 |
*/ max_state += cpufreq_get_max_state(pr->id); if (pr->flags.throttling) max_state += (pr->throttling.state_count -1); return max_state; } static int |
6503e5df0
|
180 181 |
processor_get_max_state(struct thermal_cooling_device *cdev, unsigned long *state) |
d9460fd22
|
182 183 |
{ struct acpi_device *device = cdev->devdata; |
99aa36386
|
184 |
struct acpi_processor *pr; |
d9460fd22
|
185 |
|
99aa36386
|
186 187 188 189 190 |
if (!device) return -EINVAL; pr = acpi_driver_data(device); if (!pr) |
d9460fd22
|
191 |
return -EINVAL; |
6503e5df0
|
192 193 |
*state = acpi_processor_max_state(pr); return 0; |
d9460fd22
|
194 195 196 |
} static int |
6503e5df0
|
197 198 |
processor_get_cur_state(struct thermal_cooling_device *cdev, unsigned long *cur_state) |
d9460fd22
|
199 200 |
{ struct acpi_device *device = cdev->devdata; |
99aa36386
|
201 |
struct acpi_processor *pr; |
d9460fd22
|
202 |
|
99aa36386
|
203 204 205 206 207 |
if (!device) return -EINVAL; pr = acpi_driver_data(device); if (!pr) |
d9460fd22
|
208 |
return -EINVAL; |
6503e5df0
|
209 |
*cur_state = cpufreq_get_cur_state(pr->id); |
d9460fd22
|
210 |
if (pr->flags.throttling) |
6503e5df0
|
211 212 |
*cur_state += pr->throttling.state; return 0; |
d9460fd22
|
213 214 215 |
} static int |
6503e5df0
|
216 217 |
processor_set_cur_state(struct thermal_cooling_device *cdev, unsigned long state) |
d9460fd22
|
218 219 |
{ struct acpi_device *device = cdev->devdata; |
99aa36386
|
220 |
struct acpi_processor *pr; |
d9460fd22
|
221 222 |
int result = 0; int max_pstate; |
99aa36386
|
223 224 225 226 227 |
if (!device) return -EINVAL; pr = acpi_driver_data(device); if (!pr) |
d9460fd22
|
228 229 230 231 232 233 234 235 236 |
return -EINVAL; max_pstate = cpufreq_get_max_state(pr->id); if (state > acpi_processor_max_state(pr)) return -EINVAL; if (state <= max_pstate) { if (pr->flags.throttling && pr->throttling.state) |
2a908002c
|
237 |
result = acpi_processor_set_throttling(pr, 0, false); |
d9460fd22
|
238 239 240 241 |
cpufreq_set_cur_state(pr->id, state); } else { cpufreq_set_cur_state(pr->id, max_pstate); result = acpi_processor_set_throttling(pr, |
2a908002c
|
242 |
state - max_pstate, false); |
d9460fd22
|
243 244 245 |
} return result; } |
9c8b04be4
|
246 |
const struct thermal_cooling_device_ops processor_cooling_ops = { |
d9460fd22
|
247 248 249 250 |
.get_max_state = processor_get_max_state, .get_cur_state = processor_get_cur_state, .set_cur_state = processor_set_cur_state, }; |