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8e0af514 SL |
1 | /* |
2 | * acpi_pad.c ACPI Processor Aggregator Driver | |
3 | * | |
4 | * Copyright (c) 2009, Intel Corporation. | |
5 | * | |
6 | * This program is free software; you can redistribute it and/or modify it | |
7 | * under the terms and conditions of the GNU General Public License, | |
8 | * version 2, as published by the Free Software Foundation. | |
9 | * | |
10 | * This program is distributed in the hope it will be useful, but WITHOUT | |
11 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
12 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for | |
13 | * more details. | |
14 | * | |
15 | * You should have received a copy of the GNU General Public License along with | |
16 | * this program; if not, write to the Free Software Foundation, Inc., | |
17 | * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. | |
18 | * | |
19 | */ | |
20 | ||
21 | #include <linux/kernel.h> | |
22 | #include <linux/cpumask.h> | |
23 | #include <linux/module.h> | |
24 | #include <linux/init.h> | |
25 | #include <linux/types.h> | |
26 | #include <linux/kthread.h> | |
27 | #include <linux/freezer.h> | |
28 | #include <linux/cpu.h> | |
29 | #include <linux/clockchips.h> | |
5a0e3ad6 | 30 | #include <linux/slab.h> |
8e0af514 SL |
31 | #include <acpi/acpi_bus.h> |
32 | #include <acpi/acpi_drivers.h> | |
bc83cccc | 33 | #include <asm/mwait.h> |
8e0af514 | 34 | |
a40770a9 | 35 | #define ACPI_PROCESSOR_AGGREGATOR_CLASS "acpi_pad" |
8e0af514 SL |
36 | #define ACPI_PROCESSOR_AGGREGATOR_DEVICE_NAME "Processor Aggregator" |
37 | #define ACPI_PROCESSOR_AGGREGATOR_NOTIFY 0x80 | |
38 | static DEFINE_MUTEX(isolated_cpus_lock); | |
39 | ||
8e0af514 | 40 | static unsigned long power_saving_mwait_eax; |
0dc698b9 VP |
41 | |
42 | static unsigned char tsc_detected_unstable; | |
43 | static unsigned char tsc_marked_unstable; | |
8aa4b14e CG |
44 | static unsigned char lapic_detected_unstable; |
45 | static unsigned char lapic_marked_unstable; | |
0dc698b9 | 46 | |
8e0af514 SL |
47 | static void power_saving_mwait_init(void) |
48 | { | |
49 | unsigned int eax, ebx, ecx, edx; | |
50 | unsigned int highest_cstate = 0; | |
51 | unsigned int highest_subcstate = 0; | |
52 | int i; | |
53 | ||
54 | if (!boot_cpu_has(X86_FEATURE_MWAIT)) | |
55 | return; | |
56 | if (boot_cpu_data.cpuid_level < CPUID_MWAIT_LEAF) | |
57 | return; | |
58 | ||
59 | cpuid(CPUID_MWAIT_LEAF, &eax, &ebx, &ecx, &edx); | |
60 | ||
61 | if (!(ecx & CPUID5_ECX_EXTENSIONS_SUPPORTED) || | |
62 | !(ecx & CPUID5_ECX_INTERRUPT_BREAK)) | |
63 | return; | |
64 | ||
65 | edx >>= MWAIT_SUBSTATE_SIZE; | |
66 | for (i = 0; i < 7 && edx; i++, edx >>= MWAIT_SUBSTATE_SIZE) { | |
67 | if (edx & MWAIT_SUBSTATE_MASK) { | |
68 | highest_cstate = i; | |
69 | highest_subcstate = edx & MWAIT_SUBSTATE_MASK; | |
70 | } | |
71 | } | |
72 | power_saving_mwait_eax = (highest_cstate << MWAIT_SUBSTATE_SIZE) | | |
73 | (highest_subcstate - 1); | |
74 | ||
592913ec | 75 | #if defined(CONFIG_X86) |
8e0af514 SL |
76 | switch (boot_cpu_data.x86_vendor) { |
77 | case X86_VENDOR_AMD: | |
78 | case X86_VENDOR_INTEL: | |
79 | /* | |
80 | * AMD Fam10h TSC will tick in all | |
81 | * C/P/S0/S1 states when this bit is set. | |
82 | */ | |
8aa4b14e CG |
83 | if (!boot_cpu_has(X86_FEATURE_NONSTOP_TSC)) |
84 | tsc_detected_unstable = 1; | |
85 | if (!boot_cpu_has(X86_FEATURE_ARAT)) | |
86 | lapic_detected_unstable = 1; | |
87 | break; | |
8e0af514 | 88 | default: |
8aa4b14e | 89 | /* TSC & LAPIC could halt in idle */ |
0dc698b9 | 90 | tsc_detected_unstable = 1; |
8aa4b14e | 91 | lapic_detected_unstable = 1; |
8e0af514 SL |
92 | } |
93 | #endif | |
94 | } | |
95 | ||
96 | static unsigned long cpu_weight[NR_CPUS]; | |
97 | static int tsk_in_cpu[NR_CPUS] = {[0 ... NR_CPUS-1] = -1}; | |
98 | static DECLARE_BITMAP(pad_busy_cpus_bits, NR_CPUS); | |
99 | static void round_robin_cpu(unsigned int tsk_index) | |
100 | { | |
101 | struct cpumask *pad_busy_cpus = to_cpumask(pad_busy_cpus_bits); | |
102 | cpumask_var_t tmp; | |
103 | int cpu; | |
f67538f8 AM |
104 | unsigned long min_weight = -1; |
105 | unsigned long uninitialized_var(preferred_cpu); | |
8e0af514 SL |
106 | |
107 | if (!alloc_cpumask_var(&tmp, GFP_KERNEL)) | |
108 | return; | |
109 | ||
110 | mutex_lock(&isolated_cpus_lock); | |
111 | cpumask_clear(tmp); | |
112 | for_each_cpu(cpu, pad_busy_cpus) | |
113 | cpumask_or(tmp, tmp, topology_thread_cpumask(cpu)); | |
114 | cpumask_andnot(tmp, cpu_online_mask, tmp); | |
115 | /* avoid HT sibilings if possible */ | |
116 | if (cpumask_empty(tmp)) | |
117 | cpumask_andnot(tmp, cpu_online_mask, pad_busy_cpus); | |
118 | if (cpumask_empty(tmp)) { | |
119 | mutex_unlock(&isolated_cpus_lock); | |
120 | return; | |
121 | } | |
122 | for_each_cpu(cpu, tmp) { | |
123 | if (cpu_weight[cpu] < min_weight) { | |
124 | min_weight = cpu_weight[cpu]; | |
125 | preferred_cpu = cpu; | |
126 | } | |
127 | } | |
128 | ||
129 | if (tsk_in_cpu[tsk_index] != -1) | |
130 | cpumask_clear_cpu(tsk_in_cpu[tsk_index], pad_busy_cpus); | |
131 | tsk_in_cpu[tsk_index] = preferred_cpu; | |
132 | cpumask_set_cpu(preferred_cpu, pad_busy_cpus); | |
133 | cpu_weight[preferred_cpu]++; | |
134 | mutex_unlock(&isolated_cpus_lock); | |
135 | ||
136 | set_cpus_allowed_ptr(current, cpumask_of(preferred_cpu)); | |
137 | } | |
138 | ||
139 | static void exit_round_robin(unsigned int tsk_index) | |
140 | { | |
141 | struct cpumask *pad_busy_cpus = to_cpumask(pad_busy_cpus_bits); | |
142 | cpumask_clear_cpu(tsk_in_cpu[tsk_index], pad_busy_cpus); | |
143 | tsk_in_cpu[tsk_index] = -1; | |
144 | } | |
145 | ||
146 | static unsigned int idle_pct = 5; /* percentage */ | |
147 | static unsigned int round_robin_time = 10; /* second */ | |
148 | static int power_saving_thread(void *data) | |
149 | { | |
150 | struct sched_param param = {.sched_priority = 1}; | |
151 | int do_sleep; | |
152 | unsigned int tsk_index = (unsigned long)data; | |
153 | u64 last_jiffies = 0; | |
154 | ||
155 | sched_setscheduler(current, SCHED_RR, ¶m); | |
156 | ||
157 | while (!kthread_should_stop()) { | |
158 | int cpu; | |
159 | u64 expire_time; | |
160 | ||
161 | try_to_freeze(); | |
162 | ||
163 | /* round robin to cpus */ | |
164 | if (last_jiffies + round_robin_time * HZ < jiffies) { | |
165 | last_jiffies = jiffies; | |
166 | round_robin_cpu(tsk_index); | |
167 | } | |
168 | ||
169 | do_sleep = 0; | |
170 | ||
8e0af514 SL |
171 | expire_time = jiffies + HZ * (100 - idle_pct) / 100; |
172 | ||
173 | while (!need_resched()) { | |
0dc698b9 VP |
174 | if (tsc_detected_unstable && !tsc_marked_unstable) { |
175 | /* TSC could halt in idle, so notify users */ | |
176 | mark_tsc_unstable("TSC halts in idle"); | |
177 | tsc_marked_unstable = 1; | |
178 | } | |
8aa4b14e CG |
179 | if (lapic_detected_unstable && !lapic_marked_unstable) { |
180 | int i; | |
181 | /* LAPIC could halt in idle, so notify users */ | |
182 | for_each_online_cpu(i) | |
183 | clockevents_notify( | |
184 | CLOCK_EVT_NOTIFY_BROADCAST_ON, | |
185 | &i); | |
186 | lapic_marked_unstable = 1; | |
187 | } | |
8e0af514 SL |
188 | local_irq_disable(); |
189 | cpu = smp_processor_id(); | |
8aa4b14e CG |
190 | if (lapic_marked_unstable) |
191 | clockevents_notify( | |
192 | CLOCK_EVT_NOTIFY_BROADCAST_ENTER, &cpu); | |
8e0af514 SL |
193 | stop_critical_timings(); |
194 | ||
195 | __monitor((void *)¤t_thread_info()->flags, 0, 0); | |
196 | smp_mb(); | |
197 | if (!need_resched()) | |
198 | __mwait(power_saving_mwait_eax, 1); | |
199 | ||
200 | start_critical_timings(); | |
8aa4b14e CG |
201 | if (lapic_marked_unstable) |
202 | clockevents_notify( | |
203 | CLOCK_EVT_NOTIFY_BROADCAST_EXIT, &cpu); | |
8e0af514 SL |
204 | local_irq_enable(); |
205 | ||
206 | if (jiffies > expire_time) { | |
207 | do_sleep = 1; | |
208 | break; | |
209 | } | |
210 | } | |
211 | ||
8e0af514 SL |
212 | /* |
213 | * current sched_rt has threshold for rt task running time. | |
214 | * When a rt task uses 95% CPU time, the rt thread will be | |
215 | * scheduled out for 5% CPU time to not starve other tasks. But | |
216 | * the mechanism only works when all CPUs have RT task running, | |
217 | * as if one CPU hasn't RT task, RT task from other CPUs will | |
218 | * borrow CPU time from this CPU and cause RT task use > 95% | |
3b8cb427 | 219 | * CPU time. To make 'avoid starvation' work, takes a nap here. |
8e0af514 SL |
220 | */ |
221 | if (do_sleep) | |
222 | schedule_timeout_killable(HZ * idle_pct / 100); | |
223 | } | |
224 | ||
225 | exit_round_robin(tsk_index); | |
226 | return 0; | |
227 | } | |
228 | ||
229 | static struct task_struct *ps_tsks[NR_CPUS]; | |
230 | static unsigned int ps_tsk_num; | |
231 | static int create_power_saving_task(void) | |
232 | { | |
3b8cb427 CG |
233 | int rc = -ENOMEM; |
234 | ||
8e0af514 SL |
235 | ps_tsks[ps_tsk_num] = kthread_run(power_saving_thread, |
236 | (void *)(unsigned long)ps_tsk_num, | |
237 | "power_saving/%d", ps_tsk_num); | |
3b8cb427 CG |
238 | rc = IS_ERR(ps_tsks[ps_tsk_num]) ? PTR_ERR(ps_tsks[ps_tsk_num]) : 0; |
239 | if (!rc) | |
8e0af514 | 240 | ps_tsk_num++; |
3b8cb427 CG |
241 | else |
242 | ps_tsks[ps_tsk_num] = NULL; | |
243 | ||
244 | return rc; | |
8e0af514 SL |
245 | } |
246 | ||
247 | static void destroy_power_saving_task(void) | |
248 | { | |
249 | if (ps_tsk_num > 0) { | |
250 | ps_tsk_num--; | |
251 | kthread_stop(ps_tsks[ps_tsk_num]); | |
3b8cb427 | 252 | ps_tsks[ps_tsk_num] = NULL; |
8e0af514 SL |
253 | } |
254 | } | |
255 | ||
256 | static void set_power_saving_task_num(unsigned int num) | |
257 | { | |
258 | if (num > ps_tsk_num) { | |
259 | while (ps_tsk_num < num) { | |
260 | if (create_power_saving_task()) | |
261 | return; | |
262 | } | |
263 | } else if (num < ps_tsk_num) { | |
264 | while (ps_tsk_num > num) | |
265 | destroy_power_saving_task(); | |
266 | } | |
267 | } | |
268 | ||
3b8cb427 | 269 | static void acpi_pad_idle_cpus(unsigned int num_cpus) |
8e0af514 SL |
270 | { |
271 | get_online_cpus(); | |
272 | ||
273 | num_cpus = min_t(unsigned int, num_cpus, num_online_cpus()); | |
274 | set_power_saving_task_num(num_cpus); | |
275 | ||
276 | put_online_cpus(); | |
8e0af514 SL |
277 | } |
278 | ||
279 | static uint32_t acpi_pad_idle_cpus_num(void) | |
280 | { | |
281 | return ps_tsk_num; | |
282 | } | |
283 | ||
284 | static ssize_t acpi_pad_rrtime_store(struct device *dev, | |
285 | struct device_attribute *attr, const char *buf, size_t count) | |
286 | { | |
287 | unsigned long num; | |
288 | if (strict_strtoul(buf, 0, &num)) | |
289 | return -EINVAL; | |
290 | if (num < 1 || num >= 100) | |
291 | return -EINVAL; | |
292 | mutex_lock(&isolated_cpus_lock); | |
293 | round_robin_time = num; | |
294 | mutex_unlock(&isolated_cpus_lock); | |
295 | return count; | |
296 | } | |
297 | ||
298 | static ssize_t acpi_pad_rrtime_show(struct device *dev, | |
299 | struct device_attribute *attr, char *buf) | |
300 | { | |
301 | return scnprintf(buf, PAGE_SIZE, "%d", round_robin_time); | |
302 | } | |
303 | static DEVICE_ATTR(rrtime, S_IRUGO|S_IWUSR, | |
304 | acpi_pad_rrtime_show, | |
305 | acpi_pad_rrtime_store); | |
306 | ||
307 | static ssize_t acpi_pad_idlepct_store(struct device *dev, | |
308 | struct device_attribute *attr, const char *buf, size_t count) | |
309 | { | |
310 | unsigned long num; | |
311 | if (strict_strtoul(buf, 0, &num)) | |
312 | return -EINVAL; | |
313 | if (num < 1 || num >= 100) | |
314 | return -EINVAL; | |
315 | mutex_lock(&isolated_cpus_lock); | |
316 | idle_pct = num; | |
317 | mutex_unlock(&isolated_cpus_lock); | |
318 | return count; | |
319 | } | |
320 | ||
321 | static ssize_t acpi_pad_idlepct_show(struct device *dev, | |
322 | struct device_attribute *attr, char *buf) | |
323 | { | |
324 | return scnprintf(buf, PAGE_SIZE, "%d", idle_pct); | |
325 | } | |
326 | static DEVICE_ATTR(idlepct, S_IRUGO|S_IWUSR, | |
327 | acpi_pad_idlepct_show, | |
328 | acpi_pad_idlepct_store); | |
329 | ||
330 | static ssize_t acpi_pad_idlecpus_store(struct device *dev, | |
331 | struct device_attribute *attr, const char *buf, size_t count) | |
332 | { | |
333 | unsigned long num; | |
334 | if (strict_strtoul(buf, 0, &num)) | |
335 | return -EINVAL; | |
336 | mutex_lock(&isolated_cpus_lock); | |
337 | acpi_pad_idle_cpus(num); | |
338 | mutex_unlock(&isolated_cpus_lock); | |
339 | return count; | |
340 | } | |
341 | ||
342 | static ssize_t acpi_pad_idlecpus_show(struct device *dev, | |
343 | struct device_attribute *attr, char *buf) | |
344 | { | |
345 | return cpumask_scnprintf(buf, PAGE_SIZE, | |
346 | to_cpumask(pad_busy_cpus_bits)); | |
347 | } | |
348 | static DEVICE_ATTR(idlecpus, S_IRUGO|S_IWUSR, | |
349 | acpi_pad_idlecpus_show, | |
350 | acpi_pad_idlecpus_store); | |
351 | ||
352 | static int acpi_pad_add_sysfs(struct acpi_device *device) | |
353 | { | |
354 | int result; | |
355 | ||
356 | result = device_create_file(&device->dev, &dev_attr_idlecpus); | |
357 | if (result) | |
358 | return -ENODEV; | |
359 | result = device_create_file(&device->dev, &dev_attr_idlepct); | |
360 | if (result) { | |
361 | device_remove_file(&device->dev, &dev_attr_idlecpus); | |
362 | return -ENODEV; | |
363 | } | |
364 | result = device_create_file(&device->dev, &dev_attr_rrtime); | |
365 | if (result) { | |
366 | device_remove_file(&device->dev, &dev_attr_idlecpus); | |
367 | device_remove_file(&device->dev, &dev_attr_idlepct); | |
368 | return -ENODEV; | |
369 | } | |
370 | return 0; | |
371 | } | |
372 | ||
373 | static void acpi_pad_remove_sysfs(struct acpi_device *device) | |
374 | { | |
375 | device_remove_file(&device->dev, &dev_attr_idlecpus); | |
376 | device_remove_file(&device->dev, &dev_attr_idlepct); | |
377 | device_remove_file(&device->dev, &dev_attr_rrtime); | |
378 | } | |
379 | ||
c9ad8e06 LB |
380 | /* |
381 | * Query firmware how many CPUs should be idle | |
382 | * return -1 on failure | |
383 | */ | |
384 | static int acpi_pad_pur(acpi_handle handle) | |
8e0af514 SL |
385 | { |
386 | struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL}; | |
8e0af514 | 387 | union acpi_object *package; |
c9ad8e06 | 388 | int num = -1; |
8e0af514 | 389 | |
3b8cb427 | 390 | if (ACPI_FAILURE(acpi_evaluate_object(handle, "_PUR", NULL, &buffer))) |
c9ad8e06 | 391 | return num; |
3b8cb427 CG |
392 | |
393 | if (!buffer.length || !buffer.pointer) | |
c9ad8e06 | 394 | return num; |
3b8cb427 | 395 | |
8e0af514 | 396 | package = buffer.pointer; |
c9ad8e06 LB |
397 | |
398 | if (package->type == ACPI_TYPE_PACKAGE && | |
399 | package->package.count == 2 && | |
400 | package->package.elements[0].integer.value == 1) /* rev 1 */ | |
401 | ||
402 | num = package->package.elements[1].integer.value; | |
403 | ||
8e0af514 | 404 | kfree(buffer.pointer); |
c9ad8e06 | 405 | return num; |
8e0af514 SL |
406 | } |
407 | ||
408 | /* Notify firmware how many CPUs are idle */ | |
409 | static void acpi_pad_ost(acpi_handle handle, int stat, | |
410 | uint32_t idle_cpus) | |
411 | { | |
412 | union acpi_object params[3] = { | |
413 | {.type = ACPI_TYPE_INTEGER,}, | |
414 | {.type = ACPI_TYPE_INTEGER,}, | |
415 | {.type = ACPI_TYPE_BUFFER,}, | |
416 | }; | |
417 | struct acpi_object_list arg_list = {3, params}; | |
418 | ||
419 | params[0].integer.value = ACPI_PROCESSOR_AGGREGATOR_NOTIFY; | |
420 | params[1].integer.value = stat; | |
421 | params[2].buffer.length = 4; | |
422 | params[2].buffer.pointer = (void *)&idle_cpus; | |
423 | acpi_evaluate_object(handle, "_OST", &arg_list, NULL); | |
424 | } | |
425 | ||
426 | static void acpi_pad_handle_notify(acpi_handle handle) | |
427 | { | |
3b8cb427 | 428 | int num_cpus; |
8e0af514 SL |
429 | uint32_t idle_cpus; |
430 | ||
431 | mutex_lock(&isolated_cpus_lock); | |
c9ad8e06 LB |
432 | num_cpus = acpi_pad_pur(handle); |
433 | if (num_cpus < 0) { | |
8e0af514 SL |
434 | mutex_unlock(&isolated_cpus_lock); |
435 | return; | |
436 | } | |
3b8cb427 | 437 | acpi_pad_idle_cpus(num_cpus); |
8e0af514 | 438 | idle_cpus = acpi_pad_idle_cpus_num(); |
3b8cb427 | 439 | acpi_pad_ost(handle, 0, idle_cpus); |
8e0af514 SL |
440 | mutex_unlock(&isolated_cpus_lock); |
441 | } | |
442 | ||
443 | static void acpi_pad_notify(acpi_handle handle, u32 event, | |
444 | void *data) | |
445 | { | |
446 | struct acpi_device *device = data; | |
447 | ||
448 | switch (event) { | |
449 | case ACPI_PROCESSOR_AGGREGATOR_NOTIFY: | |
450 | acpi_pad_handle_notify(handle); | |
451 | acpi_bus_generate_proc_event(device, event, 0); | |
452 | acpi_bus_generate_netlink_event(device->pnp.device_class, | |
453 | dev_name(&device->dev), event, 0); | |
454 | break; | |
455 | default: | |
456 | printk(KERN_WARNING"Unsupported event [0x%x]\n", event); | |
457 | break; | |
458 | } | |
459 | } | |
460 | ||
461 | static int acpi_pad_add(struct acpi_device *device) | |
462 | { | |
463 | acpi_status status; | |
464 | ||
465 | strcpy(acpi_device_name(device), ACPI_PROCESSOR_AGGREGATOR_DEVICE_NAME); | |
466 | strcpy(acpi_device_class(device), ACPI_PROCESSOR_AGGREGATOR_CLASS); | |
467 | ||
468 | if (acpi_pad_add_sysfs(device)) | |
469 | return -ENODEV; | |
470 | ||
471 | status = acpi_install_notify_handler(device->handle, | |
472 | ACPI_DEVICE_NOTIFY, acpi_pad_notify, device); | |
473 | if (ACPI_FAILURE(status)) { | |
474 | acpi_pad_remove_sysfs(device); | |
475 | return -ENODEV; | |
476 | } | |
477 | ||
478 | return 0; | |
479 | } | |
480 | ||
481 | static int acpi_pad_remove(struct acpi_device *device, | |
482 | int type) | |
483 | { | |
484 | mutex_lock(&isolated_cpus_lock); | |
485 | acpi_pad_idle_cpus(0); | |
486 | mutex_unlock(&isolated_cpus_lock); | |
487 | ||
488 | acpi_remove_notify_handler(device->handle, | |
489 | ACPI_DEVICE_NOTIFY, acpi_pad_notify); | |
490 | acpi_pad_remove_sysfs(device); | |
491 | return 0; | |
492 | } | |
493 | ||
494 | static const struct acpi_device_id pad_device_ids[] = { | |
495 | {"ACPI000C", 0}, | |
496 | {"", 0}, | |
497 | }; | |
498 | MODULE_DEVICE_TABLE(acpi, pad_device_ids); | |
499 | ||
500 | static struct acpi_driver acpi_pad_driver = { | |
501 | .name = "processor_aggregator", | |
502 | .class = ACPI_PROCESSOR_AGGREGATOR_CLASS, | |
503 | .ids = pad_device_ids, | |
504 | .ops = { | |
505 | .add = acpi_pad_add, | |
506 | .remove = acpi_pad_remove, | |
507 | }, | |
508 | }; | |
509 | ||
510 | static int __init acpi_pad_init(void) | |
511 | { | |
512 | power_saving_mwait_init(); | |
513 | if (power_saving_mwait_eax == 0) | |
514 | return -EINVAL; | |
515 | ||
516 | return acpi_bus_register_driver(&acpi_pad_driver); | |
517 | } | |
518 | ||
519 | static void __exit acpi_pad_exit(void) | |
520 | { | |
521 | acpi_bus_unregister_driver(&acpi_pad_driver); | |
522 | } | |
523 | ||
524 | module_init(acpi_pad_init); | |
525 | module_exit(acpi_pad_exit); | |
526 | MODULE_AUTHOR("Shaohua Li<shaohua.li@intel.com>"); | |
527 | MODULE_DESCRIPTION("ACPI Processor Aggregator Driver"); | |
528 | MODULE_LICENSE("GPL"); |