126717172SLen Brown /* 226717172SLen Brown * intel_idle.c - native hardware idle loop for modern Intel processors 326717172SLen Brown * 426717172SLen Brown * Copyright (c) 2010, Intel Corporation. 526717172SLen Brown * Len Brown <len.brown@intel.com> 626717172SLen Brown * 726717172SLen Brown * This program is free software; you can redistribute it and/or modify it 826717172SLen Brown * under the terms and conditions of the GNU General Public License, 926717172SLen Brown * version 2, as published by the Free Software Foundation. 1026717172SLen Brown * 1126717172SLen Brown * This program is distributed in the hope it will be useful, but WITHOUT 1226717172SLen Brown * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 1326717172SLen Brown * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 1426717172SLen Brown * more details. 1526717172SLen Brown * 1626717172SLen Brown * You should have received a copy of the GNU General Public License along with 1726717172SLen Brown * this program; if not, write to the Free Software Foundation, Inc., 1826717172SLen Brown * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. 1926717172SLen Brown */ 2026717172SLen Brown 2126717172SLen Brown /* 2226717172SLen Brown * intel_idle is a cpuidle driver that loads on specific Intel processors 2326717172SLen Brown * in lieu of the legacy ACPI processor_idle driver. The intent is to 2426717172SLen Brown * make Linux more efficient on these processors, as intel_idle knows 2526717172SLen Brown * more than ACPI, as well as make Linux more immune to ACPI BIOS bugs. 2626717172SLen Brown */ 2726717172SLen Brown 2826717172SLen Brown /* 2926717172SLen Brown * Design Assumptions 3026717172SLen Brown * 3126717172SLen Brown * All CPUs have same idle states as boot CPU 3226717172SLen Brown * 3326717172SLen Brown * Chipset BM_STS (bus master status) bit is a NOP 3426717172SLen Brown * for preventing entry into deep C-stats 3526717172SLen Brown */ 3626717172SLen Brown 3726717172SLen Brown /* 3826717172SLen Brown * Known limitations 3926717172SLen Brown * 4026717172SLen Brown * The driver currently initializes for_each_online_cpu() upon modprobe. 4126717172SLen Brown * It it unaware of subsequent processors hot-added to the system. 4226717172SLen Brown * This means that if you boot with maxcpus=n and later online 4326717172SLen Brown * processors above n, those processors will use C1 only. 4426717172SLen Brown * 4526717172SLen Brown * ACPI has a .suspend hack to turn off deep c-statees during suspend 4626717172SLen Brown * to avoid complications with the lapic timer workaround. 4726717172SLen Brown * Have not seen issues with suspend, but may need same workaround here. 4826717172SLen Brown * 4926717172SLen Brown * There is currently no kernel-based automatic probing/loading mechanism 5026717172SLen Brown * if the driver is built as a module. 5126717172SLen Brown */ 5226717172SLen Brown 5326717172SLen Brown /* un-comment DEBUG to enable pr_debug() statements */ 5426717172SLen Brown #define DEBUG 5526717172SLen Brown 5626717172SLen Brown #include <linux/kernel.h> 5726717172SLen Brown #include <linux/cpuidle.h> 5826717172SLen Brown #include <linux/clockchips.h> 5926717172SLen Brown #include <trace/events/power.h> 6026717172SLen Brown #include <linux/sched.h> 612a2d31c8SShaohua Li #include <linux/notifier.h> 622a2d31c8SShaohua Li #include <linux/cpu.h> 637c52d551SPaul Gortmaker #include <linux/module.h> 64b66b8b9aSAndi Kleen #include <asm/cpu_device_id.h> 65bc83ccccSH. Peter Anvin #include <asm/mwait.h> 6614796fcaSLen Brown #include <asm/msr.h> 6726717172SLen Brown 6826717172SLen Brown #define INTEL_IDLE_VERSION "0.4" 6926717172SLen Brown #define PREFIX "intel_idle: " 7026717172SLen Brown 7126717172SLen Brown static struct cpuidle_driver intel_idle_driver = { 7226717172SLen Brown .name = "intel_idle", 7326717172SLen Brown .owner = THIS_MODULE, 74a474a515SJulius Werner .en_core_tk_irqen = 1, 7526717172SLen Brown }; 7626717172SLen Brown /* intel_idle.max_cstate=0 disables driver */ 7726717172SLen Brown static int max_cstate = MWAIT_MAX_NUM_CSTATES - 1; 7826717172SLen Brown 79c4236282SLen Brown static unsigned int mwait_substates; 8026717172SLen Brown 812a2d31c8SShaohua Li #define LAPIC_TIMER_ALWAYS_RELIABLE 0xFFFFFFFF 8226717172SLen Brown /* Reliable LAPIC Timer States, bit 1 for C1 etc. */ 83d13780d4SLen Brown static unsigned int lapic_timer_reliable_states = (1 << 1); /* Default to only C1 */ 8426717172SLen Brown 85b66b8b9aSAndi Kleen struct idle_cpu { 86b66b8b9aSAndi Kleen struct cpuidle_state *state_table; 8726717172SLen Brown 8826717172SLen Brown /* 8914796fcaSLen Brown * Hardware C-state auto-demotion may not always be optimal. 9014796fcaSLen Brown * Indicate which enable bits to clear here. 9114796fcaSLen Brown */ 92b66b8b9aSAndi Kleen unsigned long auto_demotion_disable_flags; 93b66b8b9aSAndi Kleen }; 94b66b8b9aSAndi Kleen 95b66b8b9aSAndi Kleen static const struct idle_cpu *icpu; 96b66b8b9aSAndi Kleen static struct cpuidle_device __percpu *intel_idle_cpuidle_devices; 97b66b8b9aSAndi Kleen static int intel_idle(struct cpuidle_device *dev, 98b66b8b9aSAndi Kleen struct cpuidle_driver *drv, int index); 9925ac7761SDaniel Lezcano static int intel_idle_cpu_init(int cpu); 100b66b8b9aSAndi Kleen 101b66b8b9aSAndi Kleen static struct cpuidle_state *cpuidle_state_table; 10214796fcaSLen Brown 10314796fcaSLen Brown /* 104956d033fSLen Brown * Set this flag for states where the HW flushes the TLB for us 105956d033fSLen Brown * and so we don't need cross-calls to keep it consistent. 106956d033fSLen Brown * If this flag is set, SW flushes the TLB, so even if the 107956d033fSLen Brown * HW doesn't do the flushing, this flag is safe to use. 108956d033fSLen Brown */ 109956d033fSLen Brown #define CPUIDLE_FLAG_TLB_FLUSHED 0x10000 110956d033fSLen Brown 111956d033fSLen Brown /* 11226717172SLen Brown * States are indexed by the cstate number, 11326717172SLen Brown * which is also the index into the MWAIT hint array. 11426717172SLen Brown * Thus C0 is a dummy. 11526717172SLen Brown */ 11626717172SLen Brown static struct cpuidle_state nehalem_cstates[MWAIT_MAX_NUM_CSTATES] = { 11726717172SLen Brown { /* MWAIT C0 */ }, 11826717172SLen Brown { /* MWAIT C1 */ 11915e123e5SThomas Renninger .name = "C1-NHM", 12026717172SLen Brown .desc = "MWAIT 0x00", 12126717172SLen Brown .flags = CPUIDLE_FLAG_TIME_VALID, 12226717172SLen Brown .exit_latency = 3, 12326717172SLen Brown .target_residency = 6, 12426717172SLen Brown .enter = &intel_idle }, 12526717172SLen Brown { /* MWAIT C2 */ 12615e123e5SThomas Renninger .name = "C3-NHM", 12726717172SLen Brown .desc = "MWAIT 0x10", 1286110a1f4SSuresh Siddha .flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED, 12926717172SLen Brown .exit_latency = 20, 13026717172SLen Brown .target_residency = 80, 13126717172SLen Brown .enter = &intel_idle }, 13226717172SLen Brown { /* MWAIT C3 */ 13315e123e5SThomas Renninger .name = "C6-NHM", 13426717172SLen Brown .desc = "MWAIT 0x20", 1356110a1f4SSuresh Siddha .flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED, 13626717172SLen Brown .exit_latency = 200, 13726717172SLen Brown .target_residency = 800, 13826717172SLen Brown .enter = &intel_idle }, 13926717172SLen Brown }; 14026717172SLen Brown 141d13780d4SLen Brown static struct cpuidle_state snb_cstates[MWAIT_MAX_NUM_CSTATES] = { 142d13780d4SLen Brown { /* MWAIT C0 */ }, 143d13780d4SLen Brown { /* MWAIT C1 */ 14415e123e5SThomas Renninger .name = "C1-SNB", 145d13780d4SLen Brown .desc = "MWAIT 0x00", 146d13780d4SLen Brown .flags = CPUIDLE_FLAG_TIME_VALID, 147d13780d4SLen Brown .exit_latency = 1, 148ddbd550dSLen Brown .target_residency = 1, 149d13780d4SLen Brown .enter = &intel_idle }, 150d13780d4SLen Brown { /* MWAIT C2 */ 15115e123e5SThomas Renninger .name = "C3-SNB", 152d13780d4SLen Brown .desc = "MWAIT 0x10", 15300527cc6SLen Brown .flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED, 154d13780d4SLen Brown .exit_latency = 80, 155ddbd550dSLen Brown .target_residency = 211, 156d13780d4SLen Brown .enter = &intel_idle }, 157d13780d4SLen Brown { /* MWAIT C3 */ 15815e123e5SThomas Renninger .name = "C6-SNB", 159d13780d4SLen Brown .desc = "MWAIT 0x20", 16000527cc6SLen Brown .flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED, 161d13780d4SLen Brown .exit_latency = 104, 162ddbd550dSLen Brown .target_residency = 345, 163d13780d4SLen Brown .enter = &intel_idle }, 164d13780d4SLen Brown { /* MWAIT C4 */ 16515e123e5SThomas Renninger .name = "C7-SNB", 166d13780d4SLen Brown .desc = "MWAIT 0x30", 16700527cc6SLen Brown .flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED, 168d13780d4SLen Brown .exit_latency = 109, 169ddbd550dSLen Brown .target_residency = 345, 170d13780d4SLen Brown .enter = &intel_idle }, 171d13780d4SLen Brown }; 172d13780d4SLen Brown 1736edab08cSLen Brown static struct cpuidle_state ivb_cstates[MWAIT_MAX_NUM_CSTATES] = { 1746edab08cSLen Brown { /* MWAIT C0 */ }, 1756edab08cSLen Brown { /* MWAIT C1 */ 1766edab08cSLen Brown .name = "C1-IVB", 1776edab08cSLen Brown .desc = "MWAIT 0x00", 1786edab08cSLen Brown .flags = CPUIDLE_FLAG_TIME_VALID, 1796edab08cSLen Brown .exit_latency = 1, 1806edab08cSLen Brown .target_residency = 1, 1816edab08cSLen Brown .enter = &intel_idle }, 1826edab08cSLen Brown { /* MWAIT C2 */ 1836edab08cSLen Brown .name = "C3-IVB", 1846edab08cSLen Brown .desc = "MWAIT 0x10", 1856edab08cSLen Brown .flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED, 1866edab08cSLen Brown .exit_latency = 59, 1876edab08cSLen Brown .target_residency = 156, 1886edab08cSLen Brown .enter = &intel_idle }, 1896edab08cSLen Brown { /* MWAIT C3 */ 1906edab08cSLen Brown .name = "C6-IVB", 1916edab08cSLen Brown .desc = "MWAIT 0x20", 1926edab08cSLen Brown .flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED, 1936edab08cSLen Brown .exit_latency = 80, 1946edab08cSLen Brown .target_residency = 300, 1956edab08cSLen Brown .enter = &intel_idle }, 1966edab08cSLen Brown { /* MWAIT C4 */ 1976edab08cSLen Brown .name = "C7-IVB", 1986edab08cSLen Brown .desc = "MWAIT 0x30", 1996edab08cSLen Brown .flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED, 2006edab08cSLen Brown .exit_latency = 87, 2016edab08cSLen Brown .target_residency = 300, 2026edab08cSLen Brown .enter = &intel_idle }, 2036edab08cSLen Brown }; 2046edab08cSLen Brown 20526717172SLen Brown static struct cpuidle_state atom_cstates[MWAIT_MAX_NUM_CSTATES] = { 20626717172SLen Brown { /* MWAIT C0 */ }, 20726717172SLen Brown { /* MWAIT C1 */ 20815e123e5SThomas Renninger .name = "C1-ATM", 20926717172SLen Brown .desc = "MWAIT 0x00", 21026717172SLen Brown .flags = CPUIDLE_FLAG_TIME_VALID, 21126717172SLen Brown .exit_latency = 1, 21226717172SLen Brown .target_residency = 4, 21326717172SLen Brown .enter = &intel_idle }, 21426717172SLen Brown { /* MWAIT C2 */ 21515e123e5SThomas Renninger .name = "C2-ATM", 21626717172SLen Brown .desc = "MWAIT 0x10", 21726717172SLen Brown .flags = CPUIDLE_FLAG_TIME_VALID, 21826717172SLen Brown .exit_latency = 20, 21926717172SLen Brown .target_residency = 80, 22026717172SLen Brown .enter = &intel_idle }, 22126717172SLen Brown { /* MWAIT C3 */ }, 22226717172SLen Brown { /* MWAIT C4 */ 22315e123e5SThomas Renninger .name = "C4-ATM", 22426717172SLen Brown .desc = "MWAIT 0x30", 2256110a1f4SSuresh Siddha .flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED, 22626717172SLen Brown .exit_latency = 100, 22726717172SLen Brown .target_residency = 400, 22826717172SLen Brown .enter = &intel_idle }, 22926717172SLen Brown { /* MWAIT C5 */ }, 23026717172SLen Brown { /* MWAIT C6 */ 23115e123e5SThomas Renninger .name = "C6-ATM", 2327fcca7d9SLen Brown .desc = "MWAIT 0x52", 2336110a1f4SSuresh Siddha .flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED, 2347fcca7d9SLen Brown .exit_latency = 140, 2357fcca7d9SLen Brown .target_residency = 560, 2367fcca7d9SLen Brown .enter = &intel_idle }, 23726717172SLen Brown }; 23826717172SLen Brown 23995e3ec11SDavid Howells static long get_driver_data(int cstate) 2404202735eSDeepthi Dharwar { 2414202735eSDeepthi Dharwar int driver_data; 2424202735eSDeepthi Dharwar switch (cstate) { 2434202735eSDeepthi Dharwar 2444202735eSDeepthi Dharwar case 1: /* MWAIT C1 */ 2454202735eSDeepthi Dharwar driver_data = 0x00; 2464202735eSDeepthi Dharwar break; 2474202735eSDeepthi Dharwar case 2: /* MWAIT C2 */ 2484202735eSDeepthi Dharwar driver_data = 0x10; 2494202735eSDeepthi Dharwar break; 2504202735eSDeepthi Dharwar case 3: /* MWAIT C3 */ 2514202735eSDeepthi Dharwar driver_data = 0x20; 2524202735eSDeepthi Dharwar break; 2534202735eSDeepthi Dharwar case 4: /* MWAIT C4 */ 2544202735eSDeepthi Dharwar driver_data = 0x30; 2554202735eSDeepthi Dharwar break; 2564202735eSDeepthi Dharwar case 5: /* MWAIT C5 */ 2574202735eSDeepthi Dharwar driver_data = 0x40; 2584202735eSDeepthi Dharwar break; 2594202735eSDeepthi Dharwar case 6: /* MWAIT C6 */ 2604202735eSDeepthi Dharwar driver_data = 0x52; 2614202735eSDeepthi Dharwar break; 2624202735eSDeepthi Dharwar default: 2634202735eSDeepthi Dharwar driver_data = 0x00; 2644202735eSDeepthi Dharwar } 2654202735eSDeepthi Dharwar return driver_data; 2664202735eSDeepthi Dharwar } 2674202735eSDeepthi Dharwar 26826717172SLen Brown /** 26926717172SLen Brown * intel_idle 27026717172SLen Brown * @dev: cpuidle_device 27146bcfad7SDeepthi Dharwar * @drv: cpuidle driver 272e978aa7dSDeepthi Dharwar * @index: index of cpuidle state 27326717172SLen Brown * 27463ff07beSYanmin Zhang * Must be called under local_irq_disable(). 27526717172SLen Brown */ 27646bcfad7SDeepthi Dharwar static int intel_idle(struct cpuidle_device *dev, 27746bcfad7SDeepthi Dharwar struct cpuidle_driver *drv, int index) 27826717172SLen Brown { 27926717172SLen Brown unsigned long ecx = 1; /* break on interrupt flag */ 28046bcfad7SDeepthi Dharwar struct cpuidle_state *state = &drv->states[index]; 2814202735eSDeepthi Dharwar struct cpuidle_state_usage *state_usage = &dev->states_usage[index]; 2824202735eSDeepthi Dharwar unsigned long eax = (unsigned long)cpuidle_get_statedata(state_usage); 28326717172SLen Brown unsigned int cstate; 28426717172SLen Brown int cpu = smp_processor_id(); 28526717172SLen Brown 28626717172SLen Brown cstate = (((eax) >> MWAIT_SUBSTATE_SIZE) & MWAIT_CSTATE_MASK) + 1; 28726717172SLen Brown 2886110a1f4SSuresh Siddha /* 289c8381cc3SLen Brown * leave_mm() to avoid costly and often unnecessary wakeups 290c8381cc3SLen Brown * for flushing the user TLB's associated with the active mm. 2916110a1f4SSuresh Siddha */ 292c8381cc3SLen Brown if (state->flags & CPUIDLE_FLAG_TLB_FLUSHED) 2936110a1f4SSuresh Siddha leave_mm(cpu); 2946110a1f4SSuresh Siddha 29526717172SLen Brown if (!(lapic_timer_reliable_states & (1 << (cstate)))) 29626717172SLen Brown clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ENTER, &cpu); 29726717172SLen Brown 29826717172SLen Brown stop_critical_timings(); 29926717172SLen Brown if (!need_resched()) { 30026717172SLen Brown 30126717172SLen Brown __monitor((void *)¤t_thread_info()->flags, 0, 0); 30226717172SLen Brown smp_mb(); 30326717172SLen Brown if (!need_resched()) 30426717172SLen Brown __mwait(eax, ecx); 30526717172SLen Brown } 30626717172SLen Brown 30726717172SLen Brown start_critical_timings(); 30826717172SLen Brown 30926717172SLen Brown if (!(lapic_timer_reliable_states & (1 << (cstate)))) 31026717172SLen Brown clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_EXIT, &cpu); 31126717172SLen Brown 312e978aa7dSDeepthi Dharwar return index; 31326717172SLen Brown } 31426717172SLen Brown 3152a2d31c8SShaohua Li static void __setup_broadcast_timer(void *arg) 3162a2d31c8SShaohua Li { 3172a2d31c8SShaohua Li unsigned long reason = (unsigned long)arg; 3182a2d31c8SShaohua Li int cpu = smp_processor_id(); 3192a2d31c8SShaohua Li 3202a2d31c8SShaohua Li reason = reason ? 3212a2d31c8SShaohua Li CLOCK_EVT_NOTIFY_BROADCAST_ON : CLOCK_EVT_NOTIFY_BROADCAST_OFF; 3222a2d31c8SShaohua Li 3232a2d31c8SShaohua Li clockevents_notify(reason, &cpu); 3242a2d31c8SShaohua Li } 3252a2d31c8SShaohua Li 32625ac7761SDaniel Lezcano static int cpu_hotplug_notify(struct notifier_block *n, 3272a2d31c8SShaohua Li unsigned long action, void *hcpu) 3282a2d31c8SShaohua Li { 3292a2d31c8SShaohua Li int hotcpu = (unsigned long)hcpu; 33025ac7761SDaniel Lezcano struct cpuidle_device *dev; 3312a2d31c8SShaohua Li 3322a2d31c8SShaohua Li switch (action & 0xf) { 3332a2d31c8SShaohua Li case CPU_ONLINE: 33425ac7761SDaniel Lezcano 33525ac7761SDaniel Lezcano if (lapic_timer_reliable_states != LAPIC_TIMER_ALWAYS_RELIABLE) 3362a2d31c8SShaohua Li smp_call_function_single(hotcpu, __setup_broadcast_timer, 3372a2d31c8SShaohua Li (void *)true, 1); 33825ac7761SDaniel Lezcano 33925ac7761SDaniel Lezcano /* 34025ac7761SDaniel Lezcano * Some systems can hotplug a cpu at runtime after 34125ac7761SDaniel Lezcano * the kernel has booted, we have to initialize the 34225ac7761SDaniel Lezcano * driver in this case 34325ac7761SDaniel Lezcano */ 34425ac7761SDaniel Lezcano dev = per_cpu_ptr(intel_idle_cpuidle_devices, hotcpu); 34525ac7761SDaniel Lezcano if (!dev->registered) 34625ac7761SDaniel Lezcano intel_idle_cpu_init(hotcpu); 34725ac7761SDaniel Lezcano 3482a2d31c8SShaohua Li break; 3492a2d31c8SShaohua Li } 3502a2d31c8SShaohua Li return NOTIFY_OK; 3512a2d31c8SShaohua Li } 3522a2d31c8SShaohua Li 35325ac7761SDaniel Lezcano static struct notifier_block cpu_hotplug_notifier = { 35425ac7761SDaniel Lezcano .notifier_call = cpu_hotplug_notify, 3552a2d31c8SShaohua Li }; 3562a2d31c8SShaohua Li 35714796fcaSLen Brown static void auto_demotion_disable(void *dummy) 35814796fcaSLen Brown { 35914796fcaSLen Brown unsigned long long msr_bits; 36014796fcaSLen Brown 36114796fcaSLen Brown rdmsrl(MSR_NHM_SNB_PKG_CST_CFG_CTL, msr_bits); 362b66b8b9aSAndi Kleen msr_bits &= ~(icpu->auto_demotion_disable_flags); 36314796fcaSLen Brown wrmsrl(MSR_NHM_SNB_PKG_CST_CFG_CTL, msr_bits); 36414796fcaSLen Brown } 36514796fcaSLen Brown 366b66b8b9aSAndi Kleen static const struct idle_cpu idle_cpu_nehalem = { 367b66b8b9aSAndi Kleen .state_table = nehalem_cstates, 368b66b8b9aSAndi Kleen .auto_demotion_disable_flags = NHM_C1_AUTO_DEMOTE | NHM_C3_AUTO_DEMOTE, 369b66b8b9aSAndi Kleen }; 370b66b8b9aSAndi Kleen 371b66b8b9aSAndi Kleen static const struct idle_cpu idle_cpu_atom = { 372b66b8b9aSAndi Kleen .state_table = atom_cstates, 373b66b8b9aSAndi Kleen }; 374b66b8b9aSAndi Kleen 375b66b8b9aSAndi Kleen static const struct idle_cpu idle_cpu_lincroft = { 376b66b8b9aSAndi Kleen .state_table = atom_cstates, 377b66b8b9aSAndi Kleen .auto_demotion_disable_flags = ATM_LNC_C6_AUTO_DEMOTE, 378b66b8b9aSAndi Kleen }; 379b66b8b9aSAndi Kleen 380b66b8b9aSAndi Kleen static const struct idle_cpu idle_cpu_snb = { 381b66b8b9aSAndi Kleen .state_table = snb_cstates, 382b66b8b9aSAndi Kleen }; 383b66b8b9aSAndi Kleen 3846edab08cSLen Brown static const struct idle_cpu idle_cpu_ivb = { 3856edab08cSLen Brown .state_table = ivb_cstates, 3866edab08cSLen Brown }; 3876edab08cSLen Brown 388b66b8b9aSAndi Kleen #define ICPU(model, cpu) \ 389b66b8b9aSAndi Kleen { X86_VENDOR_INTEL, 6, model, X86_FEATURE_MWAIT, (unsigned long)&cpu } 390b66b8b9aSAndi Kleen 391b66b8b9aSAndi Kleen static const struct x86_cpu_id intel_idle_ids[] = { 392b66b8b9aSAndi Kleen ICPU(0x1a, idle_cpu_nehalem), 393b66b8b9aSAndi Kleen ICPU(0x1e, idle_cpu_nehalem), 394b66b8b9aSAndi Kleen ICPU(0x1f, idle_cpu_nehalem), 3958bf11938SBen Hutchings ICPU(0x25, idle_cpu_nehalem), 3968bf11938SBen Hutchings ICPU(0x2c, idle_cpu_nehalem), 3978bf11938SBen Hutchings ICPU(0x2e, idle_cpu_nehalem), 398b66b8b9aSAndi Kleen ICPU(0x1c, idle_cpu_atom), 399b66b8b9aSAndi Kleen ICPU(0x26, idle_cpu_lincroft), 4008bf11938SBen Hutchings ICPU(0x2f, idle_cpu_nehalem), 401b66b8b9aSAndi Kleen ICPU(0x2a, idle_cpu_snb), 402b66b8b9aSAndi Kleen ICPU(0x2d, idle_cpu_snb), 4036edab08cSLen Brown ICPU(0x3a, idle_cpu_ivb), 40423795e58SLen Brown ICPU(0x3e, idle_cpu_ivb), 405b66b8b9aSAndi Kleen {} 406b66b8b9aSAndi Kleen }; 407b66b8b9aSAndi Kleen MODULE_DEVICE_TABLE(x86cpu, intel_idle_ids); 408b66b8b9aSAndi Kleen 40926717172SLen Brown /* 41026717172SLen Brown * intel_idle_probe() 41126717172SLen Brown */ 41226717172SLen Brown static int intel_idle_probe(void) 41326717172SLen Brown { 414c4236282SLen Brown unsigned int eax, ebx, ecx; 415b66b8b9aSAndi Kleen const struct x86_cpu_id *id; 41626717172SLen Brown 41726717172SLen Brown if (max_cstate == 0) { 41826717172SLen Brown pr_debug(PREFIX "disabled\n"); 41926717172SLen Brown return -EPERM; 42026717172SLen Brown } 42126717172SLen Brown 422b66b8b9aSAndi Kleen id = x86_match_cpu(intel_idle_ids); 423b66b8b9aSAndi Kleen if (!id) { 424b66b8b9aSAndi Kleen if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL && 425b66b8b9aSAndi Kleen boot_cpu_data.x86 == 6) 426b66b8b9aSAndi Kleen pr_debug(PREFIX "does not run on family %d model %d\n", 427b66b8b9aSAndi Kleen boot_cpu_data.x86, boot_cpu_data.x86_model); 42826717172SLen Brown return -ENODEV; 429b66b8b9aSAndi Kleen } 43026717172SLen Brown 43126717172SLen Brown if (boot_cpu_data.cpuid_level < CPUID_MWAIT_LEAF) 43226717172SLen Brown return -ENODEV; 43326717172SLen Brown 434c4236282SLen Brown cpuid(CPUID_MWAIT_LEAF, &eax, &ebx, &ecx, &mwait_substates); 43526717172SLen Brown 43626717172SLen Brown if (!(ecx & CPUID5_ECX_EXTENSIONS_SUPPORTED) || 4375c2a9f06SThomas Renninger !(ecx & CPUID5_ECX_INTERRUPT_BREAK) || 4385c2a9f06SThomas Renninger !mwait_substates) 43926717172SLen Brown return -ENODEV; 44026717172SLen Brown 441c4236282SLen Brown pr_debug(PREFIX "MWAIT substates: 0x%x\n", mwait_substates); 44226717172SLen Brown 443b66b8b9aSAndi Kleen icpu = (const struct idle_cpu *)id->driver_data; 444b66b8b9aSAndi Kleen cpuidle_state_table = icpu->state_table; 44526717172SLen Brown 44656b9aea3SLen Brown if (boot_cpu_has(X86_FEATURE_ARAT)) /* Always Reliable APIC Timer */ 4472a2d31c8SShaohua Li lapic_timer_reliable_states = LAPIC_TIMER_ALWAYS_RELIABLE; 44825ac7761SDaniel Lezcano else 44939a74fdeSShaohua Li on_each_cpu(__setup_broadcast_timer, (void *)true, 1); 45025ac7761SDaniel Lezcano 45126717172SLen Brown pr_debug(PREFIX "v" INTEL_IDLE_VERSION 45226717172SLen Brown " model 0x%X\n", boot_cpu_data.x86_model); 45326717172SLen Brown 45426717172SLen Brown pr_debug(PREFIX "lapic_timer_reliable_states 0x%x\n", 45526717172SLen Brown lapic_timer_reliable_states); 45626717172SLen Brown return 0; 45726717172SLen Brown } 45826717172SLen Brown 45926717172SLen Brown /* 46026717172SLen Brown * intel_idle_cpuidle_devices_uninit() 46126717172SLen Brown * unregister, free cpuidle_devices 46226717172SLen Brown */ 46326717172SLen Brown static void intel_idle_cpuidle_devices_uninit(void) 46426717172SLen Brown { 46526717172SLen Brown int i; 46626717172SLen Brown struct cpuidle_device *dev; 46726717172SLen Brown 46826717172SLen Brown for_each_online_cpu(i) { 46926717172SLen Brown dev = per_cpu_ptr(intel_idle_cpuidle_devices, i); 47026717172SLen Brown cpuidle_unregister_device(dev); 47126717172SLen Brown } 47226717172SLen Brown 47326717172SLen Brown free_percpu(intel_idle_cpuidle_devices); 47426717172SLen Brown return; 47526717172SLen Brown } 47626717172SLen Brown /* 47746bcfad7SDeepthi Dharwar * intel_idle_cpuidle_driver_init() 47846bcfad7SDeepthi Dharwar * allocate, initialize cpuidle_states 47946bcfad7SDeepthi Dharwar */ 48046bcfad7SDeepthi Dharwar static int intel_idle_cpuidle_driver_init(void) 48146bcfad7SDeepthi Dharwar { 48246bcfad7SDeepthi Dharwar int cstate; 48346bcfad7SDeepthi Dharwar struct cpuidle_driver *drv = &intel_idle_driver; 48446bcfad7SDeepthi Dharwar 48546bcfad7SDeepthi Dharwar drv->state_count = 1; 48646bcfad7SDeepthi Dharwar 48746bcfad7SDeepthi Dharwar for (cstate = 1; cstate < MWAIT_MAX_NUM_CSTATES; ++cstate) { 48846bcfad7SDeepthi Dharwar int num_substates; 48946bcfad7SDeepthi Dharwar 49046bcfad7SDeepthi Dharwar if (cstate > max_cstate) { 49146bcfad7SDeepthi Dharwar printk(PREFIX "max_cstate %d reached\n", 49246bcfad7SDeepthi Dharwar max_cstate); 49346bcfad7SDeepthi Dharwar break; 49446bcfad7SDeepthi Dharwar } 49546bcfad7SDeepthi Dharwar 49646bcfad7SDeepthi Dharwar /* does the state exist in CPUID.MWAIT? */ 49746bcfad7SDeepthi Dharwar num_substates = (mwait_substates >> ((cstate) * 4)) 49846bcfad7SDeepthi Dharwar & MWAIT_SUBSTATE_MASK; 49946bcfad7SDeepthi Dharwar if (num_substates == 0) 50046bcfad7SDeepthi Dharwar continue; 50146bcfad7SDeepthi Dharwar /* is the state not enabled? */ 50246bcfad7SDeepthi Dharwar if (cpuidle_state_table[cstate].enter == NULL) { 50346bcfad7SDeepthi Dharwar /* does the driver not know about the state? */ 50446bcfad7SDeepthi Dharwar if (*cpuidle_state_table[cstate].name == '\0') 50546bcfad7SDeepthi Dharwar pr_debug(PREFIX "unaware of model 0x%x" 50646bcfad7SDeepthi Dharwar " MWAIT %d please" 50717915d58SYouquan Song " contact lenb@kernel.org\n", 50846bcfad7SDeepthi Dharwar boot_cpu_data.x86_model, cstate); 50946bcfad7SDeepthi Dharwar continue; 51046bcfad7SDeepthi Dharwar } 51146bcfad7SDeepthi Dharwar 51246bcfad7SDeepthi Dharwar if ((cstate > 2) && 51346bcfad7SDeepthi Dharwar !boot_cpu_has(X86_FEATURE_NONSTOP_TSC)) 51446bcfad7SDeepthi Dharwar mark_tsc_unstable("TSC halts in idle" 51546bcfad7SDeepthi Dharwar " states deeper than C2"); 51646bcfad7SDeepthi Dharwar 51746bcfad7SDeepthi Dharwar drv->states[drv->state_count] = /* structure copy */ 51846bcfad7SDeepthi Dharwar cpuidle_state_table[cstate]; 51946bcfad7SDeepthi Dharwar 52046bcfad7SDeepthi Dharwar drv->state_count += 1; 52146bcfad7SDeepthi Dharwar } 52246bcfad7SDeepthi Dharwar 523b66b8b9aSAndi Kleen if (icpu->auto_demotion_disable_flags) 52439a74fdeSShaohua Li on_each_cpu(auto_demotion_disable, NULL, 1); 52546bcfad7SDeepthi Dharwar 52646bcfad7SDeepthi Dharwar return 0; 52746bcfad7SDeepthi Dharwar } 52846bcfad7SDeepthi Dharwar 52946bcfad7SDeepthi Dharwar 53046bcfad7SDeepthi Dharwar /* 53165b7f839SThomas Renninger * intel_idle_cpu_init() 53226717172SLen Brown * allocate, initialize, register cpuidle_devices 53365b7f839SThomas Renninger * @cpu: cpu/core to initialize 53426717172SLen Brown */ 53525ac7761SDaniel Lezcano static int intel_idle_cpu_init(int cpu) 53626717172SLen Brown { 53765b7f839SThomas Renninger int cstate; 53826717172SLen Brown struct cpuidle_device *dev; 53926717172SLen Brown 54065b7f839SThomas Renninger dev = per_cpu_ptr(intel_idle_cpuidle_devices, cpu); 54126717172SLen Brown 54226717172SLen Brown dev->state_count = 1; 54326717172SLen Brown 54426717172SLen Brown for (cstate = 1; cstate < MWAIT_MAX_NUM_CSTATES; ++cstate) { 54526717172SLen Brown int num_substates; 54626717172SLen Brown 54726717172SLen Brown if (cstate > max_cstate) { 548dc716e96SMarcos Paulo de Souza printk(PREFIX "max_cstate %d reached\n", max_cstate); 54926717172SLen Brown break; 55026717172SLen Brown } 55126717172SLen Brown 55226717172SLen Brown /* does the state exist in CPUID.MWAIT? */ 553c4236282SLen Brown num_substates = (mwait_substates >> ((cstate) * 4)) 55426717172SLen Brown & MWAIT_SUBSTATE_MASK; 55526717172SLen Brown if (num_substates == 0) 55626717172SLen Brown continue; 55726717172SLen Brown /* is the state not enabled? */ 55865b7f839SThomas Renninger if (cpuidle_state_table[cstate].enter == NULL) 55926717172SLen Brown continue; 56026717172SLen Brown 5614202735eSDeepthi Dharwar dev->states_usage[dev->state_count].driver_data = 5624202735eSDeepthi Dharwar (void *)get_driver_data(cstate); 56326717172SLen Brown 56426717172SLen Brown dev->state_count += 1; 56526717172SLen Brown } 566dc716e96SMarcos Paulo de Souza 56765b7f839SThomas Renninger dev->cpu = cpu; 56826717172SLen Brown 56926717172SLen Brown if (cpuidle_register_device(dev)) { 57065b7f839SThomas Renninger pr_debug(PREFIX "cpuidle_register_device %d failed!\n", cpu); 57126717172SLen Brown intel_idle_cpuidle_devices_uninit(); 57226717172SLen Brown return -EIO; 57326717172SLen Brown } 57465b7f839SThomas Renninger 575b66b8b9aSAndi Kleen if (icpu->auto_demotion_disable_flags) 57665b7f839SThomas Renninger smp_call_function_single(cpu, auto_demotion_disable, NULL, 1); 57726717172SLen Brown 57826717172SLen Brown return 0; 57926717172SLen Brown } 58026717172SLen Brown 58126717172SLen Brown static int __init intel_idle_init(void) 58226717172SLen Brown { 58365b7f839SThomas Renninger int retval, i; 58426717172SLen Brown 585d1896049SThomas Renninger /* Do not load intel_idle at all for now if idle= is passed */ 586d1896049SThomas Renninger if (boot_option_idle_override != IDLE_NO_OVERRIDE) 587d1896049SThomas Renninger return -ENODEV; 588d1896049SThomas Renninger 58926717172SLen Brown retval = intel_idle_probe(); 59026717172SLen Brown if (retval) 59126717172SLen Brown return retval; 59226717172SLen Brown 59346bcfad7SDeepthi Dharwar intel_idle_cpuidle_driver_init(); 59426717172SLen Brown retval = cpuidle_register_driver(&intel_idle_driver); 59526717172SLen Brown if (retval) { 5963735d524SKonrad Rzeszutek Wilk struct cpuidle_driver *drv = cpuidle_get_driver(); 59726717172SLen Brown printk(KERN_DEBUG PREFIX "intel_idle yielding to %s", 5983735d524SKonrad Rzeszutek Wilk drv ? drv->name : "none"); 59926717172SLen Brown return retval; 60026717172SLen Brown } 60126717172SLen Brown 60265b7f839SThomas Renninger intel_idle_cpuidle_devices = alloc_percpu(struct cpuidle_device); 60365b7f839SThomas Renninger if (intel_idle_cpuidle_devices == NULL) 60465b7f839SThomas Renninger return -ENOMEM; 60565b7f839SThomas Renninger 60665b7f839SThomas Renninger for_each_online_cpu(i) { 60765b7f839SThomas Renninger retval = intel_idle_cpu_init(i); 60826717172SLen Brown if (retval) { 60926717172SLen Brown cpuidle_unregister_driver(&intel_idle_driver); 61026717172SLen Brown return retval; 61126717172SLen Brown } 61265b7f839SThomas Renninger } 6136f8c2e79SKonrad Rzeszutek Wilk register_cpu_notifier(&cpu_hotplug_notifier); 61426717172SLen Brown 61526717172SLen Brown return 0; 61626717172SLen Brown } 61726717172SLen Brown 61826717172SLen Brown static void __exit intel_idle_exit(void) 61926717172SLen Brown { 62026717172SLen Brown intel_idle_cpuidle_devices_uninit(); 62126717172SLen Brown cpuidle_unregister_driver(&intel_idle_driver); 62226717172SLen Brown 62325ac7761SDaniel Lezcano 62425ac7761SDaniel Lezcano if (lapic_timer_reliable_states != LAPIC_TIMER_ALWAYS_RELIABLE) 62539a74fdeSShaohua Li on_each_cpu(__setup_broadcast_timer, (void *)false, 1); 62625ac7761SDaniel Lezcano unregister_cpu_notifier(&cpu_hotplug_notifier); 6272a2d31c8SShaohua Li 62826717172SLen Brown return; 62926717172SLen Brown } 63026717172SLen Brown 63126717172SLen Brown module_init(intel_idle_init); 63226717172SLen Brown module_exit(intel_idle_exit); 63326717172SLen Brown 63426717172SLen Brown module_param(max_cstate, int, 0444); 63526717172SLen Brown 63626717172SLen Brown MODULE_AUTHOR("Len Brown <len.brown@intel.com>"); 63726717172SLen Brown MODULE_DESCRIPTION("Cpuidle driver for Intel Hardware v" INTEL_IDLE_VERSION); 63826717172SLen Brown MODULE_LICENSE("GPL"); 639