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1/*
2 * processor_driver.c - 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 * Copyright (C) 2013, Intel Corporation
10 * Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
25 */
26
27#include <linux/kernel.h>
28#include <linux/module.h>
29#include <linux/init.h>
30#include <linux/cpufreq.h>
31#include <linux/cpu.h>
32#include <linux/cpuidle.h>
33#include <linux/slab.h>
34#include <linux/acpi.h>
35
36#include <acpi/processor.h>
37
38#include "internal.h"
39
40#define ACPI_PROCESSOR_NOTIFY_PERFORMANCE 0x80
41#define ACPI_PROCESSOR_NOTIFY_POWER 0x81
42#define ACPI_PROCESSOR_NOTIFY_THROTTLING 0x82
43
44#define _COMPONENT ACPI_PROCESSOR_COMPONENT
45ACPI_MODULE_NAME("processor_driver");
46
47MODULE_AUTHOR("Paul Diefenbaugh");
48MODULE_DESCRIPTION("ACPI Processor Driver");
49MODULE_LICENSE("GPL");
50
51static int acpi_processor_start(struct device *dev);
52static int acpi_processor_stop(struct device *dev);
53
54static const struct acpi_device_id processor_device_ids[] = {
55 {ACPI_PROCESSOR_OBJECT_HID, 0},
56 {ACPI_PROCESSOR_DEVICE_HID, 0},
57 {"", 0},
58};
59MODULE_DEVICE_TABLE(acpi, processor_device_ids);
60
61static struct device_driver acpi_processor_driver = {
62 .name = "processor",
63 .bus = &cpu_subsys,
64 .acpi_match_table = processor_device_ids,
65 .probe = acpi_processor_start,
66 .remove = acpi_processor_stop,
67};
68
69static void acpi_processor_notify(acpi_handle handle, u32 event, void *data)
70{
71 struct acpi_device *device = data;
72 struct acpi_processor *pr;
73 int saved;
74
75 if (device->handle != handle)
76 return;
77
78 pr = acpi_driver_data(device);
79 if (!pr)
80 return;
81
82 switch (event) {
83 case ACPI_PROCESSOR_NOTIFY_PERFORMANCE:
84 saved = pr->performance_platform_limit;
85 acpi_processor_ppc_has_changed(pr, 1);
86 if (saved == pr->performance_platform_limit)
87 break;
88 acpi_bus_generate_netlink_event(device->pnp.device_class,
89 dev_name(&device->dev), event,
90 pr->performance_platform_limit);
91 break;
92 case ACPI_PROCESSOR_NOTIFY_POWER:
93 acpi_processor_cst_has_changed(pr);
94 acpi_bus_generate_netlink_event(device->pnp.device_class,
95 dev_name(&device->dev), event, 0);
96 break;
97 case ACPI_PROCESSOR_NOTIFY_THROTTLING:
98 acpi_processor_tstate_has_changed(pr);
99 acpi_bus_generate_netlink_event(device->pnp.device_class,
100 dev_name(&device->dev), event, 0);
101 break;
102 default:
103 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
104 "Unsupported event [0x%x]\n", event));
105 break;
106 }
107
108 return;
109}
110
111static int __acpi_processor_start(struct acpi_device *device);
112
113static int acpi_cpu_soft_notify(struct notifier_block *nfb,
114 unsigned long action, void *hcpu)
115{
116 unsigned int cpu = (unsigned long)hcpu;
117 struct acpi_processor *pr = per_cpu(processors, cpu);
118 struct acpi_device *device;
119 action &= ~CPU_TASKS_FROZEN;
120
121 /*
122 * CPU_STARTING and CPU_DYING must not sleep. Return here since
123 * acpi_bus_get_device() may sleep.
124 */
125 if (action == CPU_STARTING || action == CPU_DYING)
126 return NOTIFY_DONE;
127
128 if (!pr || acpi_bus_get_device(pr->handle, &device))
129 return NOTIFY_DONE;
130
131 if (action == CPU_ONLINE) {
132 /*
133 * CPU got physically hotplugged and onlined for the first time:
134 * Initialize missing things.
135 */
136 if (pr->flags.need_hotplug_init) {
137 int ret;
138
139 pr_info("Will online and init hotplugged CPU: %d\n",
140 pr->id);
141 pr->flags.need_hotplug_init = 0;
142 ret = __acpi_processor_start(device);
143 WARN(ret, "Failed to start CPU: %d\n", pr->id);
144 } else {
145 /* Normal CPU soft online event. */
146 acpi_processor_ppc_has_changed(pr, 0);
147 acpi_processor_hotplug(pr);
148 acpi_processor_reevaluate_tstate(pr, action);
149 acpi_processor_tstate_has_changed(pr);
150 }
151 } else if (action == CPU_DEAD) {
152 /* Invalidate flag.throttling after the CPU is offline. */
153 acpi_processor_reevaluate_tstate(pr, action);
154 }
155 return NOTIFY_OK;
156}
157
158static struct notifier_block acpi_cpu_notifier = {
159 .notifier_call = acpi_cpu_soft_notify,
160};
161
162#ifdef CONFIG_ACPI_CPU_FREQ_PSS
163static int acpi_pss_perf_init(struct acpi_processor *pr,
164 struct acpi_device *device)
165{
166 int result = 0;
167
168 acpi_processor_ppc_has_changed(pr, 0);
169
170 acpi_processor_get_throttling_info(pr);
171
172 if (pr->flags.throttling)
173 pr->flags.limit = 1;
174
175 pr->cdev = thermal_cooling_device_register("Processor", device,
176 &processor_cooling_ops);
177 if (IS_ERR(pr->cdev)) {
178 result = PTR_ERR(pr->cdev);
179 return result;
180 }
181
182 dev_dbg(&device->dev, "registered as cooling_device%d\n",
183 pr->cdev->id);
184
185 result = sysfs_create_link(&device->dev.kobj,
186 &pr->cdev->device.kobj,
187 "thermal_cooling");
188 if (result) {
189 dev_err(&device->dev,
190 "Failed to create sysfs link 'thermal_cooling'\n");
191 goto err_thermal_unregister;
192 }
193
194 result = sysfs_create_link(&pr->cdev->device.kobj,
195 &device->dev.kobj,
196 "device");
197 if (result) {
198 dev_err(&pr->cdev->device,
199 "Failed to create sysfs link 'device'\n");
200 goto err_remove_sysfs_thermal;
201 }
202
203 return 0;
204
205 err_remove_sysfs_thermal:
206 sysfs_remove_link(&device->dev.kobj, "thermal_cooling");
207 err_thermal_unregister:
208 thermal_cooling_device_unregister(pr->cdev);
209
210 return result;
211}
212
213static void acpi_pss_perf_exit(struct acpi_processor *pr,
214 struct acpi_device *device)
215{
216 if (pr->cdev) {
217 sysfs_remove_link(&device->dev.kobj, "thermal_cooling");
218 sysfs_remove_link(&pr->cdev->device.kobj, "device");
219 thermal_cooling_device_unregister(pr->cdev);
220 pr->cdev = NULL;
221 }
222}
223#else
224static inline int acpi_pss_perf_init(struct acpi_processor *pr,
225 struct acpi_device *device)
226{
227 return 0;
228}
229
230static inline void acpi_pss_perf_exit(struct acpi_processor *pr,
231 struct acpi_device *device) {}
232#endif /* CONFIG_ACPI_CPU_FREQ_PSS */
233
234static int __acpi_processor_start(struct acpi_device *device)
235{
236 struct acpi_processor *pr = acpi_driver_data(device);
237 acpi_status status;
238 int result = 0;
239
240 if (!pr)
241 return -ENODEV;
242
243 if (pr->flags.need_hotplug_init)
244 return 0;
245
246 result = acpi_cppc_processor_probe(pr);
247 if (result)
248 return -ENODEV;
249
250 if (!cpuidle_get_driver() || cpuidle_get_driver() == &acpi_idle_driver)
251 acpi_processor_power_init(pr);
252
253 result = acpi_pss_perf_init(pr, device);
254 if (result)
255 goto err_power_exit;
256
257 status = acpi_install_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
258 acpi_processor_notify, device);
259 if (ACPI_SUCCESS(status))
260 return 0;
261
262err_power_exit:
263 acpi_processor_power_exit(pr);
264 return result;
265}
266
267static int acpi_processor_start(struct device *dev)
268{
269 struct acpi_device *device = ACPI_COMPANION(dev);
270
271 if (!device)
272 return -ENODEV;
273
274 return __acpi_processor_start(device);
275}
276
277static int acpi_processor_stop(struct device *dev)
278{
279 struct acpi_device *device = ACPI_COMPANION(dev);
280 struct acpi_processor *pr;
281
282 if (!device)
283 return 0;
284
285 acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
286 acpi_processor_notify);
287
288 pr = acpi_driver_data(device);
289 if (!pr)
290 return 0;
291 acpi_processor_power_exit(pr);
292
293 acpi_pss_perf_exit(pr, device);
294
295 acpi_cppc_processor_exit(pr);
296
297 return 0;
298}
299
300/*
301 * We keep the driver loaded even when ACPI is not running.
302 * This is needed for the powernow-k8 driver, that works even without
303 * ACPI, but needs symbols from this driver
304 */
305
306static int __init acpi_processor_driver_init(void)
307{
308 int result = 0;
309
310 if (acpi_disabled)
311 return 0;
312
313 result = driver_register(&acpi_processor_driver);
314 if (result < 0)
315 return result;
316
317 register_hotcpu_notifier(&acpi_cpu_notifier);
318 acpi_thermal_cpufreq_init();
319 acpi_processor_ppc_init();
320 acpi_processor_throttling_init();
321 return 0;
322}
323
324static void __exit acpi_processor_driver_exit(void)
325{
326 if (acpi_disabled)
327 return;
328
329 acpi_processor_ppc_exit();
330 acpi_thermal_cpufreq_exit();
331 unregister_hotcpu_notifier(&acpi_cpu_notifier);
332 driver_unregister(&acpi_processor_driver);
333}
334
335module_init(acpi_processor_driver_init);
336module_exit(acpi_processor_driver_exit);
337
338MODULE_ALIAS("processor");
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * processor_driver.c - ACPI Processor Driver
4 *
5 * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
6 * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
7 * Copyright (C) 2004 Dominik Brodowski <linux@brodo.de>
8 * Copyright (C) 2004 Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
9 * - Added processor hotplug support
10 * Copyright (C) 2013, Intel Corporation
11 * Rafael J. Wysocki <rafael.j.wysocki@intel.com>
12 */
13
14#include <linux/kernel.h>
15#include <linux/module.h>
16#include <linux/init.h>
17#include <linux/cpufreq.h>
18#include <linux/cpu.h>
19#include <linux/cpuidle.h>
20#include <linux/slab.h>
21#include <linux/acpi.h>
22
23#include <acpi/processor.h>
24
25#include "internal.h"
26
27#define ACPI_PROCESSOR_NOTIFY_PERFORMANCE 0x80
28#define ACPI_PROCESSOR_NOTIFY_POWER 0x81
29#define ACPI_PROCESSOR_NOTIFY_THROTTLING 0x82
30#define ACPI_PROCESSOR_NOTIFY_HIGEST_PERF_CHANGED 0x85
31
32MODULE_AUTHOR("Paul Diefenbaugh");
33MODULE_DESCRIPTION("ACPI Processor Driver");
34MODULE_LICENSE("GPL");
35
36static int acpi_processor_start(struct device *dev);
37static int acpi_processor_stop(struct device *dev);
38
39static const struct acpi_device_id processor_device_ids[] = {
40 {ACPI_PROCESSOR_OBJECT_HID, 0},
41 {ACPI_PROCESSOR_DEVICE_HID, 0},
42 {"", 0},
43};
44MODULE_DEVICE_TABLE(acpi, processor_device_ids);
45
46static struct device_driver acpi_processor_driver = {
47 .name = "processor",
48 .bus = &cpu_subsys,
49 .acpi_match_table = processor_device_ids,
50 .probe = acpi_processor_start,
51 .remove = acpi_processor_stop,
52};
53
54static void acpi_processor_notify(acpi_handle handle, u32 event, void *data)
55{
56 struct acpi_device *device = data;
57 struct acpi_processor *pr;
58 int saved;
59
60 if (device->handle != handle)
61 return;
62
63 pr = acpi_driver_data(device);
64 if (!pr)
65 return;
66
67 switch (event) {
68 case ACPI_PROCESSOR_NOTIFY_PERFORMANCE:
69 saved = pr->performance_platform_limit;
70 acpi_processor_ppc_has_changed(pr, 1);
71 if (saved == pr->performance_platform_limit)
72 break;
73 acpi_bus_generate_netlink_event(device->pnp.device_class,
74 dev_name(&device->dev), event,
75 pr->performance_platform_limit);
76 break;
77 case ACPI_PROCESSOR_NOTIFY_POWER:
78 acpi_processor_power_state_has_changed(pr);
79 acpi_bus_generate_netlink_event(device->pnp.device_class,
80 dev_name(&device->dev), event, 0);
81 break;
82 case ACPI_PROCESSOR_NOTIFY_THROTTLING:
83 acpi_processor_tstate_has_changed(pr);
84 acpi_bus_generate_netlink_event(device->pnp.device_class,
85 dev_name(&device->dev), event, 0);
86 break;
87 case ACPI_PROCESSOR_NOTIFY_HIGEST_PERF_CHANGED:
88 cpufreq_update_limits(pr->id);
89 acpi_bus_generate_netlink_event(device->pnp.device_class,
90 dev_name(&device->dev), event, 0);
91 break;
92 default:
93 acpi_handle_debug(handle, "Unsupported event [0x%x]\n", event);
94 break;
95 }
96
97 return;
98}
99
100static int __acpi_processor_start(struct acpi_device *device);
101
102static int acpi_soft_cpu_online(unsigned int cpu)
103{
104 struct acpi_processor *pr = per_cpu(processors, cpu);
105 struct acpi_device *device;
106
107 if (!pr)
108 return 0;
109
110 device = acpi_fetch_acpi_dev(pr->handle);
111 if (!device)
112 return 0;
113
114 /*
115 * CPU got physically hotplugged and onlined for the first time:
116 * Initialize missing things.
117 */
118 if (pr->flags.need_hotplug_init) {
119 int ret;
120
121 pr_info("Will online and init hotplugged CPU: %d\n",
122 pr->id);
123 pr->flags.need_hotplug_init = 0;
124 ret = __acpi_processor_start(device);
125 WARN(ret, "Failed to start CPU: %d\n", pr->id);
126 } else {
127 /* Normal CPU soft online event. */
128 acpi_processor_ppc_has_changed(pr, 0);
129 acpi_processor_hotplug(pr);
130 acpi_processor_reevaluate_tstate(pr, false);
131 acpi_processor_tstate_has_changed(pr);
132 }
133 return 0;
134}
135
136static int acpi_soft_cpu_dead(unsigned int cpu)
137{
138 struct acpi_processor *pr = per_cpu(processors, cpu);
139
140 if (!pr || !acpi_fetch_acpi_dev(pr->handle))
141 return 0;
142
143 acpi_processor_reevaluate_tstate(pr, true);
144 return 0;
145}
146
147#ifdef CONFIG_ACPI_CPU_FREQ_PSS
148static void acpi_pss_perf_init(struct acpi_processor *pr)
149{
150 acpi_processor_ppc_has_changed(pr, 0);
151
152 acpi_processor_get_throttling_info(pr);
153
154 if (pr->flags.throttling)
155 pr->flags.limit = 1;
156}
157#else
158static inline void acpi_pss_perf_init(struct acpi_processor *pr) {}
159#endif /* CONFIG_ACPI_CPU_FREQ_PSS */
160
161static int __acpi_processor_start(struct acpi_device *device)
162{
163 struct acpi_processor *pr = acpi_driver_data(device);
164 acpi_status status;
165 int result = 0;
166
167 if (!pr)
168 return -ENODEV;
169
170 if (pr->flags.need_hotplug_init)
171 return 0;
172
173 result = acpi_cppc_processor_probe(pr);
174 if (result && !IS_ENABLED(CONFIG_ACPI_CPU_FREQ_PSS))
175 dev_dbg(&device->dev, "CPPC data invalid or not present\n");
176
177 if (!cpuidle_get_driver() || cpuidle_get_driver() == &acpi_idle_driver)
178 acpi_processor_power_init(pr);
179
180 acpi_pss_perf_init(pr);
181
182 result = acpi_processor_thermal_init(pr, device);
183 if (result)
184 goto err_power_exit;
185
186 status = acpi_install_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
187 acpi_processor_notify, device);
188 if (ACPI_SUCCESS(status))
189 return 0;
190
191 result = -ENODEV;
192 acpi_processor_thermal_exit(pr, device);
193
194err_power_exit:
195 acpi_processor_power_exit(pr);
196 return result;
197}
198
199static int acpi_processor_start(struct device *dev)
200{
201 struct acpi_device *device = ACPI_COMPANION(dev);
202 int ret;
203
204 if (!device)
205 return -ENODEV;
206
207 /* Protect against concurrent CPU hotplug operations */
208 cpu_hotplug_disable();
209 ret = __acpi_processor_start(device);
210 cpu_hotplug_enable();
211 return ret;
212}
213
214static int acpi_processor_stop(struct device *dev)
215{
216 struct acpi_device *device = ACPI_COMPANION(dev);
217 struct acpi_processor *pr;
218
219 if (!device)
220 return 0;
221
222 acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
223 acpi_processor_notify);
224
225 pr = acpi_driver_data(device);
226 if (!pr)
227 return 0;
228 acpi_processor_power_exit(pr);
229
230 acpi_cppc_processor_exit(pr);
231
232 acpi_processor_thermal_exit(pr, device);
233
234 return 0;
235}
236
237bool acpi_processor_cpufreq_init;
238
239static int acpi_processor_notifier(struct notifier_block *nb,
240 unsigned long event, void *data)
241{
242 struct cpufreq_policy *policy = data;
243
244 if (event == CPUFREQ_CREATE_POLICY) {
245 acpi_thermal_cpufreq_init(policy);
246 acpi_processor_ppc_init(policy);
247 } else if (event == CPUFREQ_REMOVE_POLICY) {
248 acpi_processor_ppc_exit(policy);
249 acpi_thermal_cpufreq_exit(policy);
250 }
251
252 return 0;
253}
254
255static struct notifier_block acpi_processor_notifier_block = {
256 .notifier_call = acpi_processor_notifier,
257};
258
259/*
260 * We keep the driver loaded even when ACPI is not running.
261 * This is needed for the powernow-k8 driver, that works even without
262 * ACPI, but needs symbols from this driver
263 */
264static enum cpuhp_state hp_online;
265static int __init acpi_processor_driver_init(void)
266{
267 int result = 0;
268
269 if (acpi_disabled)
270 return 0;
271
272 if (!cpufreq_register_notifier(&acpi_processor_notifier_block,
273 CPUFREQ_POLICY_NOTIFIER)) {
274 acpi_processor_cpufreq_init = true;
275 acpi_processor_ignore_ppc_init();
276 }
277
278 result = driver_register(&acpi_processor_driver);
279 if (result < 0)
280 return result;
281
282 result = cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN,
283 "acpi/cpu-drv:online",
284 acpi_soft_cpu_online, NULL);
285 if (result < 0)
286 goto err;
287 hp_online = result;
288 cpuhp_setup_state_nocalls(CPUHP_ACPI_CPUDRV_DEAD, "acpi/cpu-drv:dead",
289 NULL, acpi_soft_cpu_dead);
290
291 acpi_processor_throttling_init();
292 return 0;
293err:
294 driver_unregister(&acpi_processor_driver);
295 return result;
296}
297
298static void __exit acpi_processor_driver_exit(void)
299{
300 if (acpi_disabled)
301 return;
302
303 if (acpi_processor_cpufreq_init) {
304 cpufreq_unregister_notifier(&acpi_processor_notifier_block,
305 CPUFREQ_POLICY_NOTIFIER);
306 acpi_processor_cpufreq_init = false;
307 }
308
309 cpuhp_remove_state_nocalls(hp_online);
310 cpuhp_remove_state_nocalls(CPUHP_ACPI_CPUDRV_DEAD);
311 driver_unregister(&acpi_processor_driver);
312}
313
314module_init(acpi_processor_driver_init);
315module_exit(acpi_processor_driver_exit);
316
317MODULE_ALIAS("processor");