Commit | Line | Data |
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26717172 LB |
1 | /* |
2 | * intel_idle.c - native hardware idle loop for modern Intel processors | |
3 | * | |
4 | * Copyright (c) 2010, Intel Corporation. | |
5 | * Len Brown <len.brown@intel.com> | |
6 | * | |
7 | * This program is free software; you can redistribute it and/or modify it | |
8 | * under the terms and conditions of the GNU General Public License, | |
9 | * version 2, as published by the Free Software Foundation. | |
10 | * | |
11 | * This program is distributed in the hope it will be useful, but WITHOUT | |
12 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
13 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for | |
14 | * more details. | |
15 | * | |
16 | * You should have received a copy of the GNU General Public License along with | |
17 | * this program; if not, write to the Free Software Foundation, Inc., | |
18 | * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. | |
19 | */ | |
20 | ||
21 | /* | |
22 | * intel_idle is a cpuidle driver that loads on specific Intel processors | |
23 | * in lieu of the legacy ACPI processor_idle driver. The intent is to | |
24 | * make Linux more efficient on these processors, as intel_idle knows | |
25 | * more than ACPI, as well as make Linux more immune to ACPI BIOS bugs. | |
26 | */ | |
27 | ||
28 | /* | |
29 | * Design Assumptions | |
30 | * | |
31 | * All CPUs have same idle states as boot CPU | |
32 | * | |
33 | * Chipset BM_STS (bus master status) bit is a NOP | |
34 | * for preventing entry into deep C-stats | |
35 | */ | |
36 | ||
37 | /* | |
38 | * Known limitations | |
39 | * | |
40 | * The driver currently initializes for_each_online_cpu() upon modprobe. | |
41 | * It it unaware of subsequent processors hot-added to the system. | |
42 | * This means that if you boot with maxcpus=n and later online | |
43 | * processors above n, those processors will use C1 only. | |
44 | * | |
45 | * ACPI has a .suspend hack to turn off deep c-statees during suspend | |
46 | * to avoid complications with the lapic timer workaround. | |
47 | * Have not seen issues with suspend, but may need same workaround here. | |
48 | * | |
49 | * There is currently no kernel-based automatic probing/loading mechanism | |
50 | * if the driver is built as a module. | |
51 | */ | |
52 | ||
53 | /* un-comment DEBUG to enable pr_debug() statements */ | |
54 | #define DEBUG | |
55 | ||
56 | #include <linux/kernel.h> | |
57 | #include <linux/cpuidle.h> | |
58 | #include <linux/clockchips.h> | |
26717172 LB |
59 | #include <trace/events/power.h> |
60 | #include <linux/sched.h> | |
2a2d31c8 SL |
61 | #include <linux/notifier.h> |
62 | #include <linux/cpu.h> | |
7c52d551 | 63 | #include <linux/module.h> |
b66b8b9a | 64 | #include <asm/cpu_device_id.h> |
bc83cccc | 65 | #include <asm/mwait.h> |
14796fca | 66 | #include <asm/msr.h> |
26717172 LB |
67 | |
68 | #define INTEL_IDLE_VERSION "0.4" | |
69 | #define PREFIX "intel_idle: " | |
70 | ||
26717172 LB |
71 | static struct cpuidle_driver intel_idle_driver = { |
72 | .name = "intel_idle", | |
73 | .owner = THIS_MODULE, | |
a474a515 | 74 | .en_core_tk_irqen = 1, |
26717172 LB |
75 | }; |
76 | /* intel_idle.max_cstate=0 disables driver */ | |
77 | static int max_cstate = MWAIT_MAX_NUM_CSTATES - 1; | |
26717172 | 78 | |
c4236282 | 79 | static unsigned int mwait_substates; |
26717172 | 80 | |
2a2d31c8 | 81 | #define LAPIC_TIMER_ALWAYS_RELIABLE 0xFFFFFFFF |
26717172 | 82 | /* Reliable LAPIC Timer States, bit 1 for C1 etc. */ |
d13780d4 | 83 | static unsigned int lapic_timer_reliable_states = (1 << 1); /* Default to only C1 */ |
26717172 | 84 | |
b66b8b9a AK |
85 | struct idle_cpu { |
86 | struct cpuidle_state *state_table; | |
87 | ||
88 | /* | |
89 | * Hardware C-state auto-demotion may not always be optimal. | |
90 | * Indicate which enable bits to clear here. | |
91 | */ | |
92 | unsigned long auto_demotion_disable_flags; | |
93 | }; | |
94 | ||
95 | static const struct idle_cpu *icpu; | |
3265eba0 | 96 | static struct cpuidle_device __percpu *intel_idle_cpuidle_devices; |
46bcfad7 DD |
97 | static int intel_idle(struct cpuidle_device *dev, |
98 | struct cpuidle_driver *drv, int index); | |
25ac7761 | 99 | static int intel_idle_cpu_init(int cpu); |
26717172 LB |
100 | |
101 | static struct cpuidle_state *cpuidle_state_table; | |
102 | ||
956d033f LB |
103 | /* |
104 | * Set this flag for states where the HW flushes the TLB for us | |
105 | * and so we don't need cross-calls to keep it consistent. | |
106 | * If this flag is set, SW flushes the TLB, so even if the | |
107 | * HW doesn't do the flushing, this flag is safe to use. | |
108 | */ | |
109 | #define CPUIDLE_FLAG_TLB_FLUSHED 0x10000 | |
110 | ||
26717172 LB |
111 | /* |
112 | * States are indexed by the cstate number, | |
113 | * which is also the index into the MWAIT hint array. | |
114 | * Thus C0 is a dummy. | |
115 | */ | |
116 | static struct cpuidle_state nehalem_cstates[MWAIT_MAX_NUM_CSTATES] = { | |
117 | { /* MWAIT C0 */ }, | |
118 | { /* MWAIT C1 */ | |
15e123e5 | 119 | .name = "C1-NHM", |
26717172 | 120 | .desc = "MWAIT 0x00", |
26717172 LB |
121 | .flags = CPUIDLE_FLAG_TIME_VALID, |
122 | .exit_latency = 3, | |
26717172 LB |
123 | .target_residency = 6, |
124 | .enter = &intel_idle }, | |
125 | { /* MWAIT C2 */ | |
15e123e5 | 126 | .name = "C3-NHM", |
26717172 | 127 | .desc = "MWAIT 0x10", |
6110a1f4 | 128 | .flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED, |
26717172 | 129 | .exit_latency = 20, |
26717172 LB |
130 | .target_residency = 80, |
131 | .enter = &intel_idle }, | |
132 | { /* MWAIT C3 */ | |
15e123e5 | 133 | .name = "C6-NHM", |
26717172 | 134 | .desc = "MWAIT 0x20", |
6110a1f4 | 135 | .flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED, |
26717172 | 136 | .exit_latency = 200, |
26717172 LB |
137 | .target_residency = 800, |
138 | .enter = &intel_idle }, | |
139 | }; | |
140 | ||
d13780d4 LB |
141 | static struct cpuidle_state snb_cstates[MWAIT_MAX_NUM_CSTATES] = { |
142 | { /* MWAIT C0 */ }, | |
143 | { /* MWAIT C1 */ | |
15e123e5 | 144 | .name = "C1-SNB", |
d13780d4 | 145 | .desc = "MWAIT 0x00", |
d13780d4 LB |
146 | .flags = CPUIDLE_FLAG_TIME_VALID, |
147 | .exit_latency = 1, | |
ddbd550d | 148 | .target_residency = 1, |
d13780d4 LB |
149 | .enter = &intel_idle }, |
150 | { /* MWAIT C2 */ | |
15e123e5 | 151 | .name = "C3-SNB", |
d13780d4 | 152 | .desc = "MWAIT 0x10", |
00527cc6 | 153 | .flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED, |
d13780d4 | 154 | .exit_latency = 80, |
ddbd550d | 155 | .target_residency = 211, |
d13780d4 LB |
156 | .enter = &intel_idle }, |
157 | { /* MWAIT C3 */ | |
15e123e5 | 158 | .name = "C6-SNB", |
d13780d4 | 159 | .desc = "MWAIT 0x20", |
00527cc6 | 160 | .flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED, |
d13780d4 | 161 | .exit_latency = 104, |
ddbd550d | 162 | .target_residency = 345, |
d13780d4 LB |
163 | .enter = &intel_idle }, |
164 | { /* MWAIT C4 */ | |
15e123e5 | 165 | .name = "C7-SNB", |
d13780d4 | 166 | .desc = "MWAIT 0x30", |
00527cc6 | 167 | .flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED, |
d13780d4 | 168 | .exit_latency = 109, |
ddbd550d | 169 | .target_residency = 345, |
d13780d4 LB |
170 | .enter = &intel_idle }, |
171 | }; | |
172 | ||
6edab08c LB |
173 | static struct cpuidle_state ivb_cstates[MWAIT_MAX_NUM_CSTATES] = { |
174 | { /* MWAIT C0 */ }, | |
175 | { /* MWAIT C1 */ | |
176 | .name = "C1-IVB", | |
177 | .desc = "MWAIT 0x00", | |
178 | .flags = CPUIDLE_FLAG_TIME_VALID, | |
179 | .exit_latency = 1, | |
180 | .target_residency = 1, | |
181 | .enter = &intel_idle }, | |
182 | { /* MWAIT C2 */ | |
183 | .name = "C3-IVB", | |
184 | .desc = "MWAIT 0x10", | |
185 | .flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED, | |
186 | .exit_latency = 59, | |
187 | .target_residency = 156, | |
188 | .enter = &intel_idle }, | |
189 | { /* MWAIT C3 */ | |
190 | .name = "C6-IVB", | |
191 | .desc = "MWAIT 0x20", | |
192 | .flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED, | |
193 | .exit_latency = 80, | |
194 | .target_residency = 300, | |
195 | .enter = &intel_idle }, | |
196 | { /* MWAIT C4 */ | |
197 | .name = "C7-IVB", | |
198 | .desc = "MWAIT 0x30", | |
199 | .flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED, | |
200 | .exit_latency = 87, | |
201 | .target_residency = 300, | |
202 | .enter = &intel_idle }, | |
203 | }; | |
204 | ||
26717172 LB |
205 | static struct cpuidle_state atom_cstates[MWAIT_MAX_NUM_CSTATES] = { |
206 | { /* MWAIT C0 */ }, | |
207 | { /* MWAIT C1 */ | |
15e123e5 | 208 | .name = "C1-ATM", |
26717172 | 209 | .desc = "MWAIT 0x00", |
26717172 LB |
210 | .flags = CPUIDLE_FLAG_TIME_VALID, |
211 | .exit_latency = 1, | |
26717172 LB |
212 | .target_residency = 4, |
213 | .enter = &intel_idle }, | |
214 | { /* MWAIT C2 */ | |
15e123e5 | 215 | .name = "C2-ATM", |
26717172 | 216 | .desc = "MWAIT 0x10", |
26717172 LB |
217 | .flags = CPUIDLE_FLAG_TIME_VALID, |
218 | .exit_latency = 20, | |
26717172 LB |
219 | .target_residency = 80, |
220 | .enter = &intel_idle }, | |
221 | { /* MWAIT C3 */ }, | |
222 | { /* MWAIT C4 */ | |
15e123e5 | 223 | .name = "C4-ATM", |
26717172 | 224 | .desc = "MWAIT 0x30", |
6110a1f4 | 225 | .flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED, |
26717172 | 226 | .exit_latency = 100, |
26717172 LB |
227 | .target_residency = 400, |
228 | .enter = &intel_idle }, | |
229 | { /* MWAIT C5 */ }, | |
230 | { /* MWAIT C6 */ | |
15e123e5 | 231 | .name = "C6-ATM", |
7fcca7d9 | 232 | .desc = "MWAIT 0x52", |
6110a1f4 | 233 | .flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED, |
7fcca7d9 | 234 | .exit_latency = 140, |
7fcca7d9 LB |
235 | .target_residency = 560, |
236 | .enter = &intel_idle }, | |
26717172 LB |
237 | }; |
238 | ||
95e3ec11 | 239 | static long get_driver_data(int cstate) |
4202735e DD |
240 | { |
241 | int driver_data; | |
242 | switch (cstate) { | |
243 | ||
244 | case 1: /* MWAIT C1 */ | |
245 | driver_data = 0x00; | |
246 | break; | |
247 | case 2: /* MWAIT C2 */ | |
248 | driver_data = 0x10; | |
249 | break; | |
250 | case 3: /* MWAIT C3 */ | |
251 | driver_data = 0x20; | |
252 | break; | |
253 | case 4: /* MWAIT C4 */ | |
254 | driver_data = 0x30; | |
255 | break; | |
256 | case 5: /* MWAIT C5 */ | |
257 | driver_data = 0x40; | |
258 | break; | |
259 | case 6: /* MWAIT C6 */ | |
260 | driver_data = 0x52; | |
261 | break; | |
262 | default: | |
263 | driver_data = 0x00; | |
264 | } | |
265 | return driver_data; | |
266 | } | |
267 | ||
26717172 LB |
268 | /** |
269 | * intel_idle | |
270 | * @dev: cpuidle_device | |
46bcfad7 | 271 | * @drv: cpuidle driver |
e978aa7d | 272 | * @index: index of cpuidle state |
26717172 | 273 | * |
63ff07be | 274 | * Must be called under local_irq_disable(). |
26717172 | 275 | */ |
46bcfad7 DD |
276 | static int intel_idle(struct cpuidle_device *dev, |
277 | struct cpuidle_driver *drv, int index) | |
26717172 LB |
278 | { |
279 | unsigned long ecx = 1; /* break on interrupt flag */ | |
46bcfad7 | 280 | struct cpuidle_state *state = &drv->states[index]; |
4202735e DD |
281 | struct cpuidle_state_usage *state_usage = &dev->states_usage[index]; |
282 | unsigned long eax = (unsigned long)cpuidle_get_statedata(state_usage); | |
26717172 | 283 | unsigned int cstate; |
26717172 LB |
284 | int cpu = smp_processor_id(); |
285 | ||
286 | cstate = (((eax) >> MWAIT_SUBSTATE_SIZE) & MWAIT_CSTATE_MASK) + 1; | |
287 | ||
6110a1f4 | 288 | /* |
c8381cc3 LB |
289 | * leave_mm() to avoid costly and often unnecessary wakeups |
290 | * for flushing the user TLB's associated with the active mm. | |
6110a1f4 | 291 | */ |
c8381cc3 | 292 | if (state->flags & CPUIDLE_FLAG_TLB_FLUSHED) |
6110a1f4 SS |
293 | leave_mm(cpu); |
294 | ||
26717172 LB |
295 | if (!(lapic_timer_reliable_states & (1 << (cstate)))) |
296 | clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ENTER, &cpu); | |
297 | ||
26717172 | 298 | stop_critical_timings(); |
26717172 LB |
299 | if (!need_resched()) { |
300 | ||
301 | __monitor((void *)¤t_thread_info()->flags, 0, 0); | |
302 | smp_mb(); | |
303 | if (!need_resched()) | |
304 | __mwait(eax, ecx); | |
305 | } | |
306 | ||
307 | start_critical_timings(); | |
308 | ||
26717172 LB |
309 | if (!(lapic_timer_reliable_states & (1 << (cstate)))) |
310 | clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_EXIT, &cpu); | |
311 | ||
e978aa7d | 312 | return index; |
26717172 LB |
313 | } |
314 | ||
2a2d31c8 SL |
315 | static void __setup_broadcast_timer(void *arg) |
316 | { | |
317 | unsigned long reason = (unsigned long)arg; | |
318 | int cpu = smp_processor_id(); | |
319 | ||
320 | reason = reason ? | |
321 | CLOCK_EVT_NOTIFY_BROADCAST_ON : CLOCK_EVT_NOTIFY_BROADCAST_OFF; | |
322 | ||
323 | clockevents_notify(reason, &cpu); | |
324 | } | |
325 | ||
25ac7761 DL |
326 | static int cpu_hotplug_notify(struct notifier_block *n, |
327 | unsigned long action, void *hcpu) | |
2a2d31c8 SL |
328 | { |
329 | int hotcpu = (unsigned long)hcpu; | |
25ac7761 | 330 | struct cpuidle_device *dev; |
2a2d31c8 SL |
331 | |
332 | switch (action & 0xf) { | |
333 | case CPU_ONLINE: | |
25ac7761 DL |
334 | |
335 | if (lapic_timer_reliable_states != LAPIC_TIMER_ALWAYS_RELIABLE) | |
336 | smp_call_function_single(hotcpu, __setup_broadcast_timer, | |
337 | (void *)true, 1); | |
338 | ||
339 | /* | |
340 | * Some systems can hotplug a cpu at runtime after | |
341 | * the kernel has booted, we have to initialize the | |
342 | * driver in this case | |
343 | */ | |
344 | dev = per_cpu_ptr(intel_idle_cpuidle_devices, hotcpu); | |
345 | if (!dev->registered) | |
346 | intel_idle_cpu_init(hotcpu); | |
347 | ||
2a2d31c8 | 348 | break; |
2a2d31c8 SL |
349 | } |
350 | return NOTIFY_OK; | |
351 | } | |
352 | ||
25ac7761 DL |
353 | static struct notifier_block cpu_hotplug_notifier = { |
354 | .notifier_call = cpu_hotplug_notify, | |
2a2d31c8 SL |
355 | }; |
356 | ||
14796fca LB |
357 | static void auto_demotion_disable(void *dummy) |
358 | { | |
359 | unsigned long long msr_bits; | |
360 | ||
361 | rdmsrl(MSR_NHM_SNB_PKG_CST_CFG_CTL, msr_bits); | |
b66b8b9a | 362 | msr_bits &= ~(icpu->auto_demotion_disable_flags); |
14796fca LB |
363 | wrmsrl(MSR_NHM_SNB_PKG_CST_CFG_CTL, msr_bits); |
364 | } | |
365 | ||
b66b8b9a AK |
366 | static const struct idle_cpu idle_cpu_nehalem = { |
367 | .state_table = nehalem_cstates, | |
b66b8b9a AK |
368 | .auto_demotion_disable_flags = NHM_C1_AUTO_DEMOTE | NHM_C3_AUTO_DEMOTE, |
369 | }; | |
370 | ||
371 | static const struct idle_cpu idle_cpu_atom = { | |
372 | .state_table = atom_cstates, | |
373 | }; | |
374 | ||
375 | static const struct idle_cpu idle_cpu_lincroft = { | |
376 | .state_table = atom_cstates, | |
377 | .auto_demotion_disable_flags = ATM_LNC_C6_AUTO_DEMOTE, | |
378 | }; | |
379 | ||
380 | static const struct idle_cpu idle_cpu_snb = { | |
381 | .state_table = snb_cstates, | |
382 | }; | |
383 | ||
6edab08c LB |
384 | static const struct idle_cpu idle_cpu_ivb = { |
385 | .state_table = ivb_cstates, | |
386 | }; | |
387 | ||
b66b8b9a AK |
388 | #define ICPU(model, cpu) \ |
389 | { X86_VENDOR_INTEL, 6, model, X86_FEATURE_MWAIT, (unsigned long)&cpu } | |
390 | ||
391 | static const struct x86_cpu_id intel_idle_ids[] = { | |
392 | ICPU(0x1a, idle_cpu_nehalem), | |
393 | ICPU(0x1e, idle_cpu_nehalem), | |
394 | ICPU(0x1f, idle_cpu_nehalem), | |
8bf11938 BH |
395 | ICPU(0x25, idle_cpu_nehalem), |
396 | ICPU(0x2c, idle_cpu_nehalem), | |
397 | ICPU(0x2e, idle_cpu_nehalem), | |
b66b8b9a AK |
398 | ICPU(0x1c, idle_cpu_atom), |
399 | ICPU(0x26, idle_cpu_lincroft), | |
8bf11938 | 400 | ICPU(0x2f, idle_cpu_nehalem), |
b66b8b9a AK |
401 | ICPU(0x2a, idle_cpu_snb), |
402 | ICPU(0x2d, idle_cpu_snb), | |
6edab08c | 403 | ICPU(0x3a, idle_cpu_ivb), |
23795e58 | 404 | ICPU(0x3e, idle_cpu_ivb), |
b66b8b9a AK |
405 | {} |
406 | }; | |
407 | MODULE_DEVICE_TABLE(x86cpu, intel_idle_ids); | |
408 | ||
26717172 LB |
409 | /* |
410 | * intel_idle_probe() | |
411 | */ | |
412 | static int intel_idle_probe(void) | |
413 | { | |
c4236282 | 414 | unsigned int eax, ebx, ecx; |
b66b8b9a | 415 | const struct x86_cpu_id *id; |
26717172 LB |
416 | |
417 | if (max_cstate == 0) { | |
418 | pr_debug(PREFIX "disabled\n"); | |
419 | return -EPERM; | |
420 | } | |
421 | ||
b66b8b9a AK |
422 | id = x86_match_cpu(intel_idle_ids); |
423 | if (!id) { | |
424 | if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL && | |
425 | boot_cpu_data.x86 == 6) | |
426 | pr_debug(PREFIX "does not run on family %d model %d\n", | |
427 | boot_cpu_data.x86, boot_cpu_data.x86_model); | |
26717172 | 428 | return -ENODEV; |
b66b8b9a | 429 | } |
26717172 LB |
430 | |
431 | if (boot_cpu_data.cpuid_level < CPUID_MWAIT_LEAF) | |
432 | return -ENODEV; | |
433 | ||
c4236282 | 434 | cpuid(CPUID_MWAIT_LEAF, &eax, &ebx, &ecx, &mwait_substates); |
26717172 LB |
435 | |
436 | if (!(ecx & CPUID5_ECX_EXTENSIONS_SUPPORTED) || | |
5c2a9f06 TR |
437 | !(ecx & CPUID5_ECX_INTERRUPT_BREAK) || |
438 | !mwait_substates) | |
26717172 | 439 | return -ENODEV; |
26717172 | 440 | |
c4236282 | 441 | pr_debug(PREFIX "MWAIT substates: 0x%x\n", mwait_substates); |
26717172 | 442 | |
b66b8b9a AK |
443 | icpu = (const struct idle_cpu *)id->driver_data; |
444 | cpuidle_state_table = icpu->state_table; | |
26717172 | 445 | |
56b9aea3 | 446 | if (boot_cpu_has(X86_FEATURE_ARAT)) /* Always Reliable APIC Timer */ |
2a2d31c8 | 447 | lapic_timer_reliable_states = LAPIC_TIMER_ALWAYS_RELIABLE; |
25ac7761 | 448 | else |
39a74fde | 449 | on_each_cpu(__setup_broadcast_timer, (void *)true, 1); |
25ac7761 | 450 | |
26717172 LB |
451 | pr_debug(PREFIX "v" INTEL_IDLE_VERSION |
452 | " model 0x%X\n", boot_cpu_data.x86_model); | |
453 | ||
454 | pr_debug(PREFIX "lapic_timer_reliable_states 0x%x\n", | |
455 | lapic_timer_reliable_states); | |
456 | return 0; | |
457 | } | |
458 | ||
459 | /* | |
460 | * intel_idle_cpuidle_devices_uninit() | |
461 | * unregister, free cpuidle_devices | |
462 | */ | |
463 | static void intel_idle_cpuidle_devices_uninit(void) | |
464 | { | |
465 | int i; | |
466 | struct cpuidle_device *dev; | |
467 | ||
468 | for_each_online_cpu(i) { | |
469 | dev = per_cpu_ptr(intel_idle_cpuidle_devices, i); | |
470 | cpuidle_unregister_device(dev); | |
471 | } | |
472 | ||
473 | free_percpu(intel_idle_cpuidle_devices); | |
474 | return; | |
475 | } | |
46bcfad7 DD |
476 | /* |
477 | * intel_idle_cpuidle_driver_init() | |
478 | * allocate, initialize cpuidle_states | |
479 | */ | |
480 | static int intel_idle_cpuidle_driver_init(void) | |
481 | { | |
482 | int cstate; | |
483 | struct cpuidle_driver *drv = &intel_idle_driver; | |
484 | ||
485 | drv->state_count = 1; | |
486 | ||
487 | for (cstate = 1; cstate < MWAIT_MAX_NUM_CSTATES; ++cstate) { | |
488 | int num_substates; | |
489 | ||
490 | if (cstate > max_cstate) { | |
491 | printk(PREFIX "max_cstate %d reached\n", | |
492 | max_cstate); | |
493 | break; | |
494 | } | |
495 | ||
496 | /* does the state exist in CPUID.MWAIT? */ | |
497 | num_substates = (mwait_substates >> ((cstate) * 4)) | |
498 | & MWAIT_SUBSTATE_MASK; | |
499 | if (num_substates == 0) | |
500 | continue; | |
501 | /* is the state not enabled? */ | |
502 | if (cpuidle_state_table[cstate].enter == NULL) { | |
503 | /* does the driver not know about the state? */ | |
504 | if (*cpuidle_state_table[cstate].name == '\0') | |
505 | pr_debug(PREFIX "unaware of model 0x%x" | |
506 | " MWAIT %d please" | |
17915d58 | 507 | " contact lenb@kernel.org\n", |
46bcfad7 DD |
508 | boot_cpu_data.x86_model, cstate); |
509 | continue; | |
510 | } | |
511 | ||
512 | if ((cstate > 2) && | |
513 | !boot_cpu_has(X86_FEATURE_NONSTOP_TSC)) | |
514 | mark_tsc_unstable("TSC halts in idle" | |
515 | " states deeper than C2"); | |
516 | ||
517 | drv->states[drv->state_count] = /* structure copy */ | |
518 | cpuidle_state_table[cstate]; | |
519 | ||
520 | drv->state_count += 1; | |
521 | } | |
522 | ||
b66b8b9a | 523 | if (icpu->auto_demotion_disable_flags) |
39a74fde | 524 | on_each_cpu(auto_demotion_disable, NULL, 1); |
46bcfad7 DD |
525 | |
526 | return 0; | |
527 | } | |
528 | ||
529 | ||
26717172 | 530 | /* |
65b7f839 | 531 | * intel_idle_cpu_init() |
26717172 | 532 | * allocate, initialize, register cpuidle_devices |
65b7f839 | 533 | * @cpu: cpu/core to initialize |
26717172 | 534 | */ |
25ac7761 | 535 | static int intel_idle_cpu_init(int cpu) |
26717172 | 536 | { |
65b7f839 | 537 | int cstate; |
26717172 LB |
538 | struct cpuidle_device *dev; |
539 | ||
65b7f839 | 540 | dev = per_cpu_ptr(intel_idle_cpuidle_devices, cpu); |
26717172 | 541 | |
65b7f839 | 542 | dev->state_count = 1; |
26717172 | 543 | |
65b7f839 TR |
544 | for (cstate = 1; cstate < MWAIT_MAX_NUM_CSTATES; ++cstate) { |
545 | int num_substates; | |
26717172 | 546 | |
65b7f839 | 547 | if (cstate > max_cstate) { |
dc716e96 | 548 | printk(PREFIX "max_cstate %d reached\n", max_cstate); |
65b7f839 TR |
549 | break; |
550 | } | |
26717172 | 551 | |
65b7f839 TR |
552 | /* does the state exist in CPUID.MWAIT? */ |
553 | num_substates = (mwait_substates >> ((cstate) * 4)) | |
554 | & MWAIT_SUBSTATE_MASK; | |
555 | if (num_substates == 0) | |
556 | continue; | |
557 | /* is the state not enabled? */ | |
558 | if (cpuidle_state_table[cstate].enter == NULL) | |
559 | continue; | |
26717172 | 560 | |
65b7f839 TR |
561 | dev->states_usage[dev->state_count].driver_data = |
562 | (void *)get_driver_data(cstate); | |
26717172 | 563 | |
dc716e96 MPS |
564 | dev->state_count += 1; |
565 | } | |
566 | ||
65b7f839 | 567 | dev->cpu = cpu; |
26717172 | 568 | |
65b7f839 TR |
569 | if (cpuidle_register_device(dev)) { |
570 | pr_debug(PREFIX "cpuidle_register_device %d failed!\n", cpu); | |
571 | intel_idle_cpuidle_devices_uninit(); | |
572 | return -EIO; | |
26717172 LB |
573 | } |
574 | ||
b66b8b9a | 575 | if (icpu->auto_demotion_disable_flags) |
65b7f839 TR |
576 | smp_call_function_single(cpu, auto_demotion_disable, NULL, 1); |
577 | ||
26717172 LB |
578 | return 0; |
579 | } | |
26717172 LB |
580 | |
581 | static int __init intel_idle_init(void) | |
582 | { | |
65b7f839 | 583 | int retval, i; |
26717172 | 584 | |
d1896049 TR |
585 | /* Do not load intel_idle at all for now if idle= is passed */ |
586 | if (boot_option_idle_override != IDLE_NO_OVERRIDE) | |
587 | return -ENODEV; | |
588 | ||
26717172 LB |
589 | retval = intel_idle_probe(); |
590 | if (retval) | |
591 | return retval; | |
592 | ||
46bcfad7 | 593 | intel_idle_cpuidle_driver_init(); |
26717172 LB |
594 | retval = cpuidle_register_driver(&intel_idle_driver); |
595 | if (retval) { | |
3735d524 | 596 | struct cpuidle_driver *drv = cpuidle_get_driver(); |
26717172 | 597 | printk(KERN_DEBUG PREFIX "intel_idle yielding to %s", |
3735d524 | 598 | drv ? drv->name : "none"); |
26717172 LB |
599 | return retval; |
600 | } | |
601 | ||
65b7f839 TR |
602 | intel_idle_cpuidle_devices = alloc_percpu(struct cpuidle_device); |
603 | if (intel_idle_cpuidle_devices == NULL) | |
604 | return -ENOMEM; | |
605 | ||
606 | for_each_online_cpu(i) { | |
607 | retval = intel_idle_cpu_init(i); | |
608 | if (retval) { | |
609 | cpuidle_unregister_driver(&intel_idle_driver); | |
610 | return retval; | |
611 | } | |
26717172 | 612 | } |
6f8c2e79 | 613 | register_cpu_notifier(&cpu_hotplug_notifier); |
26717172 LB |
614 | |
615 | return 0; | |
616 | } | |
617 | ||
618 | static void __exit intel_idle_exit(void) | |
619 | { | |
620 | intel_idle_cpuidle_devices_uninit(); | |
621 | cpuidle_unregister_driver(&intel_idle_driver); | |
622 | ||
25ac7761 DL |
623 | |
624 | if (lapic_timer_reliable_states != LAPIC_TIMER_ALWAYS_RELIABLE) | |
39a74fde | 625 | on_each_cpu(__setup_broadcast_timer, (void *)false, 1); |
25ac7761 | 626 | unregister_cpu_notifier(&cpu_hotplug_notifier); |
2a2d31c8 | 627 | |
26717172 LB |
628 | return; |
629 | } | |
630 | ||
631 | module_init(intel_idle_init); | |
632 | module_exit(intel_idle_exit); | |
633 | ||
26717172 | 634 | module_param(max_cstate, int, 0444); |
26717172 LB |
635 | |
636 | MODULE_AUTHOR("Len Brown <len.brown@intel.com>"); | |
637 | MODULE_DESCRIPTION("Cpuidle driver for Intel Hardware v" INTEL_IDLE_VERSION); | |
638 | MODULE_LICENSE("GPL"); |