/* * intel_idle.c - native hardware idle loop for modern Intel processors * * Copyright (c) 2013, Intel Corporation. * Len Brown * * This program is free software; you can redistribute it and/or modify it * under the terms and conditions of the GNU General Public License, * version 2, as published by the Free Software Foundation. * * This program is distributed in the hope 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. * * You should have received a copy of the GNU General Public License along with * this program; if not, write to the Free Software Foundation, Inc., * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. */ /* * intel_idle is a cpuidle driver that loads on specific Intel processors * in lieu of the legacy ACPI processor_idle driver. The intent is to * make Linux more efficient on these processors, as intel_idle knows * more than ACPI, as well as make Linux more immune to ACPI BIOS bugs. */ /* * Design Assumptions * * All CPUs have same idle states as boot CPU * * Chipset BM_STS (bus master status) bit is a NOP * for preventing entry into deep C-stats */ /* * Known limitations * * The driver currently initializes for_each_online_cpu() upon modprobe. * It it unaware of subsequent processors hot-added to the system. * This means that if you boot with maxcpus=n and later online * processors above n, those processors will use C1 only. * * ACPI has a .suspend hack to turn off deep c-statees during suspend * to avoid complications with the lapic timer workaround. * Have not seen issues with suspend, but may need same workaround here. * */ /* un-comment DEBUG to enable pr_debug() statements */ #define DEBUG #include #include #include #include #include #include #include #include #include #include #include #include #define INTEL_IDLE_VERSION "0.4.1" #define PREFIX "intel_idle: " static struct cpuidle_driver intel_idle_driver = { .name = "intel_idle", .owner = THIS_MODULE, }; /* intel_idle.max_cstate=0 disables driver */ static int max_cstate = CPUIDLE_STATE_MAX - 1; static unsigned int mwait_substates; #define LAPIC_TIMER_ALWAYS_RELIABLE 0xFFFFFFFF /* Reliable LAPIC Timer States, bit 1 for C1 etc. */ static unsigned int lapic_timer_reliable_states = (1 << 1); /* Default to only C1 */ struct idle_cpu { struct cpuidle_state *state_table; /* * Hardware C-state auto-demotion may not always be optimal. * Indicate which enable bits to clear here. */ unsigned long auto_demotion_disable_flags; bool byt_auto_demotion_disable_flag; bool disable_promotion_to_c1e; }; static const struct idle_cpu *icpu; static struct cpuidle_device __percpu *intel_idle_cpuidle_devices; static int intel_idle(struct cpuidle_device *dev, struct cpuidle_driver *drv, int index); static void intel_idle_freeze(struct cpuidle_device *dev, struct cpuidle_driver *drv, int index); static int intel_idle_cpu_init(int cpu); static struct cpuidle_state *cpuidle_state_table; /* * Set this flag for states where the HW flushes the TLB for us * and so we don't need cross-calls to keep it consistent. * If this flag is set, SW flushes the TLB, so even if the * HW doesn't do the flushing, this flag is safe to use. */ #define CPUIDLE_FLAG_TLB_FLUSHED 0x10000 /* * MWAIT takes an 8-bit "hint" in EAX "suggesting" * the C-state (top nibble) and sub-state (bottom nibble) * 0x00 means "MWAIT(C1)", 0x10 means "MWAIT(C2)" etc. * * We store the hint at the top of our "flags" for each state. */ #define flg2MWAIT(flags) (((flags) >> 24) & 0xFF) #define MWAIT2flg(eax) ((eax & 0xFF) << 24) /* * States are indexed by the cstate number, * which is also the index into the MWAIT hint array. * Thus C0 is a dummy. */ static struct cpuidle_state nehalem_cstates[] = { { .name = "C1-NHM", .desc = "MWAIT 0x00", .flags = MWAIT2flg(0x00), .exit_latency = 3, .target_residency = 6, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C1E-NHM", .desc = "MWAIT 0x01", .flags = MWAIT2flg(0x01), .exit_latency = 10, .target_residency = 20, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C3-NHM", .desc = "MWAIT 0x10", .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 20, .target_residency = 80, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C6-NHM", .desc = "MWAIT 0x20", .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 200, .target_residency = 800, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .enter = NULL } }; static struct cpuidle_state snb_cstates[] = { { .name = "C1-SNB", .desc = "MWAIT 0x00", .flags = MWAIT2flg(0x00), .exit_latency = 2, .target_residency = 2, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C1E-SNB", .desc = "MWAIT 0x01", .flags = MWAIT2flg(0x01), .exit_latency = 10, .target_residency = 20, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C3-SNB", .desc = "MWAIT 0x10", .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 80, .target_residency = 211, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C6-SNB", .desc = "MWAIT 0x20", .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 104, .target_residency = 345, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C7-SNB", .desc = "MWAIT 0x30", .flags = MWAIT2flg(0x30) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 109, .target_residency = 345, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .enter = NULL } }; static struct cpuidle_state byt_cstates[] = { { .name = "C1-BYT", .desc = "MWAIT 0x00", .flags = MWAIT2flg(0x00), .exit_latency = 1, .target_residency = 1, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C6N-BYT", .desc = "MWAIT 0x58", .flags = MWAIT2flg(0x58) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 300, .target_residency = 275, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C6S-BYT", .desc = "MWAIT 0x52", .flags = MWAIT2flg(0x52) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 500, .target_residency = 560, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C7-BYT", .desc = "MWAIT 0x60", .flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 1200, .target_residency = 4000, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C7S-BYT", .desc = "MWAIT 0x64", .flags = MWAIT2flg(0x64) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 10000, .target_residency = 20000, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .enter = NULL } }; static struct cpuidle_state cht_cstates[] = { { .name = "C1-CHT", .desc = "MWAIT 0x00", .flags = MWAIT2flg(0x00), .exit_latency = 1, .target_residency = 1, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C6N-CHT", .desc = "MWAIT 0x58", .flags = MWAIT2flg(0x58) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 80, .target_residency = 275, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C6S-CHT", .desc = "MWAIT 0x52", .flags = MWAIT2flg(0x52) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 200, .target_residency = 560, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C7-CHT", .desc = "MWAIT 0x60", .flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 1200, .target_residency = 4000, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C7S-CHT", .desc = "MWAIT 0x64", .flags = MWAIT2flg(0x64) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 10000, .target_residency = 20000, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .enter = NULL } }; static struct cpuidle_state ivb_cstates[] = { { .name = "C1-IVB", .desc = "MWAIT 0x00", .flags = MWAIT2flg(0x00), .exit_latency = 1, .target_residency = 1, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C1E-IVB", .desc = "MWAIT 0x01", .flags = MWAIT2flg(0x01), .exit_latency = 10, .target_residency = 20, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C3-IVB", .desc = "MWAIT 0x10", .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 59, .target_residency = 156, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C6-IVB", .desc = "MWAIT 0x20", .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 80, .target_residency = 300, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C7-IVB", .desc = "MWAIT 0x30", .flags = MWAIT2flg(0x30) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 87, .target_residency = 300, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .enter = NULL } }; static struct cpuidle_state ivt_cstates[] = { { .name = "C1-IVT", .desc = "MWAIT 0x00", .flags = MWAIT2flg(0x00), .exit_latency = 1, .target_residency = 1, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C1E-IVT", .desc = "MWAIT 0x01", .flags = MWAIT2flg(0x01), .exit_latency = 10, .target_residency = 80, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C3-IVT", .desc = "MWAIT 0x10", .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 59, .target_residency = 156, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C6-IVT", .desc = "MWAIT 0x20", .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 82, .target_residency = 300, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .enter = NULL } }; static struct cpuidle_state ivt_cstates_4s[] = { { .name = "C1-IVT-4S", .desc = "MWAIT 0x00", .flags = MWAIT2flg(0x00), .exit_latency = 1, .target_residency = 1, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C1E-IVT-4S", .desc = "MWAIT 0x01", .flags = MWAIT2flg(0x01), .exit_latency = 10, .target_residency = 250, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C3-IVT-4S", .desc = "MWAIT 0x10", .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 59, .target_residency = 300, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C6-IVT-4S", .desc = "MWAIT 0x20", .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 84, .target_residency = 400, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .enter = NULL } }; static struct cpuidle_state ivt_cstates_8s[] = { { .name = "C1-IVT-8S", .desc = "MWAIT 0x00", .flags = MWAIT2flg(0x00), .exit_latency = 1, .target_residency = 1, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C1E-IVT-8S", .desc = "MWAIT 0x01", .flags = MWAIT2flg(0x01), .exit_latency = 10, .target_residency = 500, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C3-IVT-8S", .desc = "MWAIT 0x10", .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 59, .target_residency = 600, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C6-IVT-8S", .desc = "MWAIT 0x20", .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 88, .target_residency = 700, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .enter = NULL } }; static struct cpuidle_state hsw_cstates[] = { { .name = "C1-HSW", .desc = "MWAIT 0x00", .flags = MWAIT2flg(0x00), .exit_latency = 2, .target_residency = 2, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C1E-HSW", .desc = "MWAIT 0x01", .flags = MWAIT2flg(0x01), .exit_latency = 10, .target_residency = 20, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C3-HSW", .desc = "MWAIT 0x10", .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 33, .target_residency = 100, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C6-HSW", .desc = "MWAIT 0x20", .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 133, .target_residency = 400, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C7s-HSW", .desc = "MWAIT 0x32", .flags = MWAIT2flg(0x32) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 166, .target_residency = 500, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C8-HSW", .desc = "MWAIT 0x40", .flags = MWAIT2flg(0x40) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 300, .target_residency = 900, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C9-HSW", .desc = "MWAIT 0x50", .flags = MWAIT2flg(0x50) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 600, .target_residency = 1800, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C10-HSW", .desc = "MWAIT 0x60", .flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 2600, .target_residency = 7700, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .enter = NULL } }; static struct cpuidle_state bdw_cstates[] = { { .name = "C1-BDW", .desc = "MWAIT 0x00", .flags = MWAIT2flg(0x00), .exit_latency = 2, .target_residency = 2, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C1E-BDW", .desc = "MWAIT 0x01", .flags = MWAIT2flg(0x01), .exit_latency = 10, .target_residency = 20, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C3-BDW", .desc = "MWAIT 0x10", .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 40, .target_residency = 100, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C6-BDW", .desc = "MWAIT 0x20", .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 133, .target_residency = 400, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C7s-BDW", .desc = "MWAIT 0x32", .flags = MWAIT2flg(0x32) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 166, .target_residency = 500, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C8-BDW", .desc = "MWAIT 0x40", .flags = MWAIT2flg(0x40) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 300, .target_residency = 900, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C9-BDW", .desc = "MWAIT 0x50", .flags = MWAIT2flg(0x50) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 600, .target_residency = 1800, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C10-BDW", .desc = "MWAIT 0x60", .flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 2600, .target_residency = 7700, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .enter = NULL } }; static struct cpuidle_state skl_cstates[] = { { .name = "C1-SKL", .desc = "MWAIT 0x00", .flags = MWAIT2flg(0x00), .exit_latency = 2, .target_residency = 2, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C1E-SKL", .desc = "MWAIT 0x01", .flags = MWAIT2flg(0x01), .exit_latency = 10, .target_residency = 20, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C3-SKL", .desc = "MWAIT 0x10", .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 70, .target_residency = 100, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C6-SKL", .desc = "MWAIT 0x20", .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 85, .target_residency = 200, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C7s-SKL", .desc = "MWAIT 0x33", .flags = MWAIT2flg(0x33) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 124, .target_residency = 800, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C8-SKL", .desc = "MWAIT 0x40", .flags = MWAIT2flg(0x40) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 200, .target_residency = 800, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C9-SKL", .desc = "MWAIT 0x50", .flags = MWAIT2flg(0x50) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 480, .target_residency = 5000, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C10-SKL", .desc = "MWAIT 0x60", .flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 890, .target_residency = 5000, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .enter = NULL } }; static struct cpuidle_state skx_cstates[] = { { .name = "C1-SKX", .desc = "MWAIT 0x00", .flags = MWAIT2flg(0x00), .exit_latency = 2, .target_residency = 2, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C1E-SKX", .desc = "MWAIT 0x01", .flags = MWAIT2flg(0x01), .exit_latency = 10, .target_residency = 20, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C6-SKX", .desc = "MWAIT 0x20", .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 133, .target_residency = 600, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .enter = NULL } }; static struct cpuidle_state atom_cstates[] = { { .name = "C1E-ATM", .desc = "MWAIT 0x00", .flags = MWAIT2flg(0x00), .exit_latency = 10, .target_residency = 20, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C2-ATM", .desc = "MWAIT 0x10", .flags = MWAIT2flg(0x10), .exit_latency = 20, .target_residency = 80, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C4-ATM", .desc = "MWAIT 0x30", .flags = MWAIT2flg(0x30) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 100, .target_residency = 400, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C6-ATM", .desc = "MWAIT 0x52", .flags = MWAIT2flg(0x52) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 140, .target_residency = 560, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .enter = NULL } }; static struct cpuidle_state tangier_cstates[] = { { .name = "C1-TNG", .desc = "MWAIT 0x00", .flags = MWAIT2flg(0x00), .exit_latency = 1, .target_residency = 4, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C4-TNG", .desc = "MWAIT 0x30", .flags = MWAIT2flg(0x30) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 100, .target_residency = 400, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C6-TNG", .desc = "MWAIT 0x52", .flags = MWAIT2flg(0x52) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 140, .target_residency = 560, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C7-TNG", .desc = "MWAIT 0x60", .flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 1200, .target_residency = 4000, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C9-TNG", .desc = "MWAIT 0x64", .flags = MWAIT2flg(0x64) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 10000, .target_residency = 20000, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .enter = NULL } }; static struct cpuidle_state avn_cstates[] = { { .name = "C1-AVN", .desc = "MWAIT 0x00", .flags = MWAIT2flg(0x00), .exit_latency = 2, .target_residency = 2, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C6-AVN", .desc = "MWAIT 0x51", .flags = MWAIT2flg(0x51) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 15, .target_residency = 45, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .enter = NULL } }; static struct cpuidle_state knl_cstates[] = { { .name = "C1-KNL", .desc = "MWAIT 0x00", .flags = MWAIT2flg(0x00), .exit_latency = 1, .target_residency = 2, .enter = &intel_idle, .enter_freeze = intel_idle_freeze }, { .name = "C6-KNL", .desc = "MWAIT 0x10", .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 120, .target_residency = 500, .enter = &intel_idle, .enter_freeze = intel_idle_freeze }, { .enter = NULL } }; static struct cpuidle_state bxt_cstates[] = { { .name = "C1-BXT", .desc = "MWAIT 0x00", .flags = MWAIT2flg(0x00), .exit_latency = 2, .target_residency = 2, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C1E-BXT", .desc = "MWAIT 0x01", .flags = MWAIT2flg(0x01), .exit_latency = 10, .target_residency = 20, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C6-BXT", .desc = "MWAIT 0x20", .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 133, .target_residency = 133, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C7s-BXT", .desc = "MWAIT 0x31", .flags = MWAIT2flg(0x31) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 155, .target_residency = 155, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C8-BXT", .desc = "MWAIT 0x40", .flags = MWAIT2flg(0x40) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 1000, .target_residency = 1000, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C9-BXT", .desc = "MWAIT 0x50", .flags = MWAIT2flg(0x50) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 2000, .target_residency = 2000, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C10-BXT", .desc = "MWAIT 0x60", .flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 10000, .target_residency = 10000, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .enter = NULL } }; static struct cpuidle_state dnv_cstates[] = { { .name = "C1-DNV", .desc = "MWAIT 0x00", .flags = MWAIT2flg(0x00), .exit_latency = 2, .target_residency = 2, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C1E-DNV", .desc = "MWAIT 0x01", .flags = MWAIT2flg(0x01), .exit_latency = 10, .target_residency = 20, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .name = "C6-DNV", .desc = "MWAIT 0x20", .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 50, .target_residency = 500, .enter = &intel_idle, .enter_freeze = intel_idle_freeze, }, { .enter = NULL } }; /** * intel_idle * @dev: cpuidle_device * @drv: cpuidle driver * @index: index of cpuidle state * * Must be called under local_irq_disable(). */ static __cpuidle int intel_idle(struct cpuidle_device *dev, struct cpuidle_driver *drv, int index) { unsigned long ecx = 1; /* break on interrupt flag */ struct cpuidle_state *state = &drv->states[index]; unsigned long eax = flg2MWAIT(state->flags); unsigned int cstate; int cpu = smp_processor_id(); cstate = (((eax) >> MWAIT_SUBSTATE_SIZE) & MWAIT_CSTATE_MASK) + 1; /* * leave_mm() to avoid costly and often unnecessary wakeups * for flushing the user TLB's associated with the active mm. */ if (state->flags & CPUIDLE_FLAG_TLB_FLUSHED) leave_mm(cpu); if (!(lapic_timer_reliable_states & (1 << (cstate)))) tick_broadcast_enter(); mwait_idle_with_hints(eax, ecx); if (!(lapic_timer_reliable_states & (1 << (cstate)))) tick_broadcast_exit(); return index; } /** * intel_idle_freeze - simplified "enter" callback routine for suspend-to-idle * @dev: cpuidle_device * @drv: cpuidle driver * @index: state index */ static void intel_idle_freeze(struct cpuidle_device *dev, struct cpuidle_driver *drv, int index) { unsigned long ecx = 1; /* break on interrupt flag */ unsigned long eax = flg2MWAIT(drv->states[index].flags); mwait_idle_with_hints(eax, ecx); } static void __setup_broadcast_timer(void *arg) { unsigned long on = (unsigned long)arg; if (on) tick_broadcast_enable(); else tick_broadcast_disable(); } static int cpu_hotplug_notify(struct notifier_block *n, unsigned long action, void *hcpu) { int hotcpu = (unsigned long)hcpu; struct cpuidle_device *dev; switch (action & ~CPU_TASKS_FROZEN) { case CPU_ONLINE: if (lapic_timer_reliable_states != LAPIC_TIMER_ALWAYS_RELIABLE) smp_call_function_single(hotcpu, __setup_broadcast_timer, (void *)true, 1); /* * Some systems can hotplug a cpu at runtime after * the kernel has booted, we have to initialize the * driver in this case */ dev = per_cpu_ptr(intel_idle_cpuidle_devices, hotcpu); if (dev->registered) break; if (intel_idle_cpu_init(hotcpu)) return NOTIFY_BAD; break; } return NOTIFY_OK; } static struct notifier_block cpu_hotplug_notifier = { .notifier_call = cpu_hotplug_notify, }; static void auto_demotion_disable(void *dummy) { unsigned long long msr_bits; rdmsrl(MSR_NHM_SNB_PKG_CST_CFG_CTL, msr_bits); msr_bits &= ~(icpu->auto_demotion_disable_flags); wrmsrl(MSR_NHM_SNB_PKG_CST_CFG_CTL, msr_bits); } static void c1e_promotion_disable(void *dummy) { unsigned long long msr_bits; rdmsrl(MSR_IA32_POWER_CTL, msr_bits); msr_bits &= ~0x2; wrmsrl(MSR_IA32_POWER_CTL, msr_bits); } static const struct idle_cpu idle_cpu_nehalem = { .state_table = nehalem_cstates, .auto_demotion_disable_flags = NHM_C1_AUTO_DEMOTE | NHM_C3_AUTO_DEMOTE, .disable_promotion_to_c1e = true, }; static const struct idle_cpu idle_cpu_atom = { .state_table = atom_cstates, }; static const struct idle_cpu idle_cpu_tangier = { .state_table = tangier_cstates, }; static const struct idle_cpu idle_cpu_lincroft = { .state_table = atom_cstates, .auto_demotion_disable_flags = ATM_LNC_C6_AUTO_DEMOTE, }; static const struct idle_cpu idle_cpu_snb = { .state_table = snb_cstates, .disable_promotion_to_c1e = true, }; static const struct idle_cpu idle_cpu_byt = { .state_table = byt_cstates, .disable_promotion_to_c1e = true, .byt_auto_demotion_disable_flag = true, }; static const struct idle_cpu idle_cpu_cht = { .state_table = cht_cstates, .disable_promotion_to_c1e = true, .byt_auto_demotion_disable_flag = true, }; static const struct idle_cpu idle_cpu_ivb = { .state_table = ivb_cstates, .disable_promotion_to_c1e = true, }; static const struct idle_cpu idle_cpu_ivt = { .state_table = ivt_cstates, .disable_promotion_to_c1e = true, }; static const struct idle_cpu idle_cpu_hsw = { .state_table = hsw_cstates, .disable_promotion_to_c1e = true, }; static const struct idle_cpu idle_cpu_bdw = { .state_table = bdw_cstates, .disable_promotion_to_c1e = true, }; static const struct idle_cpu idle_cpu_skl = { .state_table = skl_cstates, .disable_promotion_to_c1e = true, }; static const struct idle_cpu idle_cpu_skx = { .state_table = skx_cstates, .disable_promotion_to_c1e = true, }; static const struct idle_cpu idle_cpu_avn = { .state_table = avn_cstates, .disable_promotion_to_c1e = true, }; static const struct idle_cpu idle_cpu_knl = { .state_table = knl_cstates, }; static const struct idle_cpu idle_cpu_bxt = { .state_table = bxt_cstates, .disable_promotion_to_c1e = true, }; static const struct idle_cpu idle_cpu_dnv = { .state_table = dnv_cstates, .disable_promotion_to_c1e = true, }; #define ICPU(model, cpu) \ { X86_VENDOR_INTEL, 6, model, X86_FEATURE_MWAIT, (unsigned long)&cpu } static const struct x86_cpu_id intel_idle_ids[] __initconst = { ICPU(INTEL_FAM6_NEHALEM_EP, idle_cpu_nehalem), ICPU(INTEL_FAM6_NEHALEM, idle_cpu_nehalem), ICPU(INTEL_FAM6_NEHALEM_G, idle_cpu_nehalem), ICPU(INTEL_FAM6_WESTMERE, idle_cpu_nehalem), ICPU(INTEL_FAM6_WESTMERE_EP, idle_cpu_nehalem), ICPU(INTEL_FAM6_NEHALEM_EX, idle_cpu_nehalem), ICPU(INTEL_FAM6_ATOM_PINEVIEW, idle_cpu_atom), ICPU(INTEL_FAM6_ATOM_LINCROFT, idle_cpu_lincroft), ICPU(INTEL_FAM6_WESTMERE_EX, idle_cpu_nehalem), ICPU(INTEL_FAM6_SANDYBRIDGE, idle_cpu_snb), ICPU(INTEL_FAM6_SANDYBRIDGE_X, idle_cpu_snb), ICPU(INTEL_FAM6_ATOM_CEDARVIEW, idle_cpu_atom), ICPU(INTEL_FAM6_ATOM_SILVERMONT1, idle_cpu_byt), ICPU(INTEL_FAM6_ATOM_MERRIFIELD, idle_cpu_tangier), ICPU(INTEL_FAM6_ATOM_AIRMONT, idle_cpu_cht), ICPU(INTEL_FAM6_IVYBRIDGE, idle_cpu_ivb), ICPU(INTEL_FAM6_IVYBRIDGE_X, idle_cpu_ivt), ICPU(INTEL_FAM6_HASWELL_CORE, idle_cpu_hsw), ICPU(INTEL_FAM6_HASWELL_X, idle_cpu_hsw), ICPU(INTEL_FAM6_HASWELL_ULT, idle_cpu_hsw), ICPU(INTEL_FAM6_HASWELL_GT3E, idle_cpu_hsw), ICPU(INTEL_FAM6_ATOM_SILVERMONT2, idle_cpu_avn), ICPU(INTEL_FAM6_BROADWELL_CORE, idle_cpu_bdw), ICPU(INTEL_FAM6_BROADWELL_GT3E, idle_cpu_bdw), ICPU(INTEL_FAM6_BROADWELL_X, idle_cpu_bdw), ICPU(INTEL_FAM6_BROADWELL_XEON_D, idle_cpu_bdw), ICPU(INTEL_FAM6_SKYLAKE_MOBILE, idle_cpu_skl), ICPU(INTEL_FAM6_SKYLAKE_DESKTOP, idle_cpu_skl), ICPU(INTEL_FAM6_KABYLAKE_MOBILE, idle_cpu_skl), ICPU(INTEL_FAM6_KABYLAKE_DESKTOP, idle_cpu_skl), ICPU(INTEL_FAM6_SKYLAKE_X, idle_cpu_skx), ICPU(INTEL_FAM6_XEON_PHI_KNL, idle_cpu_knl), ICPU(INTEL_FAM6_XEON_PHI_KNM, idle_cpu_knl), ICPU(INTEL_FAM6_ATOM_GOLDMONT, idle_cpu_bxt), ICPU(INTEL_FAM6_ATOM_DENVERTON, idle_cpu_dnv), {} }; /* * intel_idle_probe() */ static int __init intel_idle_probe(void) { unsigned int eax, ebx, ecx; const struct x86_cpu_id *id; if (max_cstate == 0) { pr_debug(PREFIX "disabled\n"); return -EPERM; } id = x86_match_cpu(intel_idle_ids); if (!id) { if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL && boot_cpu_data.x86 == 6) pr_debug(PREFIX "does not run on family %d model %d\n", boot_cpu_data.x86, boot_cpu_data.x86_model); return -ENODEV; } if (boot_cpu_data.cpuid_level < CPUID_MWAIT_LEAF) return -ENODEV; cpuid(CPUID_MWAIT_LEAF, &eax, &ebx, &ecx, &mwait_substates); if (!(ecx & CPUID5_ECX_EXTENSIONS_SUPPORTED) || !(ecx & CPUID5_ECX_INTERRUPT_BREAK) || !mwait_substates) return -ENODEV; pr_debug(PREFIX "MWAIT substates: 0x%x\n", mwait_substates); icpu = (const struct idle_cpu *)id->driver_data; cpuidle_state_table = icpu->state_table; pr_debug(PREFIX "v" INTEL_IDLE_VERSION " model 0x%X\n", boot_cpu_data.x86_model); return 0; } /* * intel_idle_cpuidle_devices_uninit() * Unregisters the cpuidle devices. */ static void intel_idle_cpuidle_devices_uninit(void) { int i; struct cpuidle_device *dev; for_each_online_cpu(i) { dev = per_cpu_ptr(intel_idle_cpuidle_devices, i); cpuidle_unregister_device(dev); } } /* * ivt_idle_state_table_update(void) * * Tune IVT multi-socket targets * Assumption: num_sockets == (max_package_num + 1) */ static void ivt_idle_state_table_update(void) { /* IVT uses a different table for 1-2, 3-4, and > 4 sockets */ int cpu, package_num, num_sockets = 1; for_each_online_cpu(cpu) { package_num = topology_physical_package_id(cpu); if (package_num + 1 > num_sockets) { num_sockets = package_num + 1; if (num_sockets > 4) { cpuidle_state_table = ivt_cstates_8s; return; } } } if (num_sockets > 2) cpuidle_state_table = ivt_cstates_4s; /* else, 1 and 2 socket systems use default ivt_cstates */ } /* * Translate IRTL (Interrupt Response Time Limit) MSR to usec */ static unsigned int irtl_ns_units[] = { 1, 32, 1024, 32768, 1048576, 33554432, 0, 0 }; static unsigned long long irtl_2_usec(unsigned long long irtl) { unsigned long long ns; if (!irtl) return 0; ns = irtl_ns_units[(irtl >> 10) & 0x7]; return div64_u64((irtl & 0x3FF) * ns, 1000); } /* * bxt_idle_state_table_update(void) * * On BXT, we trust the IRTL to show the definitive maximum latency * We use the same value for target_residency. */ static void bxt_idle_state_table_update(void) { unsigned long long msr; unsigned int usec; rdmsrl(MSR_PKGC6_IRTL, msr); usec = irtl_2_usec(msr); if (usec) { bxt_cstates[2].exit_latency = usec; bxt_cstates[2].target_residency = usec; } rdmsrl(MSR_PKGC7_IRTL, msr); usec = irtl_2_usec(msr); if (usec) { bxt_cstates[3].exit_latency = usec; bxt_cstates[3].target_residency = usec; } rdmsrl(MSR_PKGC8_IRTL, msr); usec = irtl_2_usec(msr); if (usec) { bxt_cstates[4].exit_latency = usec; bxt_cstates[4].target_residency = usec; } rdmsrl(MSR_PKGC9_IRTL, msr); usec = irtl_2_usec(msr); if (usec) { bxt_cstates[5].exit_latency = usec; bxt_cstates[5].target_residency = usec; } rdmsrl(MSR_PKGC10_IRTL, msr); usec = irtl_2_usec(msr); if (usec) { bxt_cstates[6].exit_latency = usec; bxt_cstates[6].target_residency = usec; } } /* * sklh_idle_state_table_update(void) * * On SKL-H (model 0x5e) disable C8 and C9 if: * C10 is enabled and SGX disabled */ static void sklh_idle_state_table_update(void) { unsigned long long msr; unsigned int eax, ebx, ecx, edx; /* if PC10 disabled via cmdline intel_idle.max_cstate=7 or shallower */ if (max_cstate <= 7) return; /* if PC10 not present in CPUID.MWAIT.EDX */ if ((mwait_substates & (0xF << 28)) == 0) return; rdmsrl(MSR_NHM_SNB_PKG_CST_CFG_CTL, msr); /* PC10 is not enabled in PKG C-state limit */ if ((msr & 0xF) != 8) return; ecx = 0; cpuid(7, &eax, &ebx, &ecx, &edx); /* if SGX is present */ if (ebx & (1 << 2)) { rdmsrl(MSR_IA32_FEATURE_CONTROL, msr); /* if SGX is enabled */ if (msr & (1 << 18)) return; } skl_cstates[5].disabled = 1; /* C8-SKL */ skl_cstates[6].disabled = 1; /* C9-SKL */ } /* * intel_idle_state_table_update() * * Update the default state_table for this CPU-id */ static void intel_idle_state_table_update(void) { switch (boot_cpu_data.x86_model) { case INTEL_FAM6_IVYBRIDGE_X: ivt_idle_state_table_update(); break; case INTEL_FAM6_ATOM_GOLDMONT: bxt_idle_state_table_update(); break; case INTEL_FAM6_SKYLAKE_DESKTOP: sklh_idle_state_table_update(); break; } } /* * intel_idle_cpuidle_driver_init() * allocate, initialize cpuidle_states */ static void __init intel_idle_cpuidle_driver_init(void) { int cstate; struct cpuidle_driver *drv = &intel_idle_driver; intel_idle_state_table_update(); drv->state_count = 1; for (cstate = 0; cstate < CPUIDLE_STATE_MAX; ++cstate) { int num_substates, mwait_hint, mwait_cstate; if ((cpuidle_state_table[cstate].enter == NULL) && (cpuidle_state_table[cstate].enter_freeze == NULL)) break; if (cstate + 1 > max_cstate) { printk(PREFIX "max_cstate %d reached\n", max_cstate); break; } mwait_hint = flg2MWAIT(cpuidle_state_table[cstate].flags); mwait_cstate = MWAIT_HINT2CSTATE(mwait_hint); /* number of sub-states for this state in CPUID.MWAIT */ num_substates = (mwait_substates >> ((mwait_cstate + 1) * 4)) & MWAIT_SUBSTATE_MASK; /* if NO sub-states for this state in CPUID, skip it */ if (num_substates == 0) continue; /* if state marked as disabled, skip it */ if (cpuidle_state_table[cstate].disabled != 0) { pr_debug(PREFIX "state %s is disabled", cpuidle_state_table[cstate].name); continue; } if (((mwait_cstate + 1) > 2) && !boot_cpu_has(X86_FEATURE_NONSTOP_TSC)) mark_tsc_unstable("TSC halts in idle" " states deeper than C2"); drv->states[drv->state_count] = /* structure copy */ cpuidle_state_table[cstate]; drv->state_count += 1; } if (icpu->byt_auto_demotion_disable_flag) { wrmsrl(MSR_CC6_DEMOTION_POLICY_CONFIG, 0); wrmsrl(MSR_MC6_DEMOTION_POLICY_CONFIG, 0); } } /* * intel_idle_cpu_init() * allocate, initialize, register cpuidle_devices * @cpu: cpu/core to initialize */ static int intel_idle_cpu_init(int cpu) { struct cpuidle_device *dev; dev = per_cpu_ptr(intel_idle_cpuidle_devices, cpu); dev->cpu = cpu; if (cpuidle_register_device(dev)) { pr_debug(PREFIX "cpuidle_register_device %d failed!\n", cpu); return -EIO; } if (icpu->auto_demotion_disable_flags) smp_call_function_single(cpu, auto_demotion_disable, NULL, 1); if (icpu->disable_promotion_to_c1e) smp_call_function_single(cpu, c1e_promotion_disable, NULL, 1); return 0; } static int __init intel_idle_init(void) { int retval, i; /* Do not load intel_idle at all for now if idle= is passed */ if (boot_option_idle_override != IDLE_NO_OVERRIDE) return -ENODEV; retval = intel_idle_probe(); if (retval) return retval; intel_idle_cpuidle_devices = alloc_percpu(struct cpuidle_device); if (intel_idle_cpuidle_devices == NULL) return -ENOMEM; intel_idle_cpuidle_driver_init(); retval = cpuidle_register_driver(&intel_idle_driver); if (retval) { struct cpuidle_driver *drv = cpuidle_get_driver(); printk(KERN_DEBUG PREFIX "intel_idle yielding to %s", drv ? drv->name : "none"); free_percpu(intel_idle_cpuidle_devices); return retval; } cpu_notifier_register_begin(); for_each_online_cpu(i) { retval = intel_idle_cpu_init(i); if (retval) { intel_idle_cpuidle_devices_uninit(); cpu_notifier_register_done(); cpuidle_unregister_driver(&intel_idle_driver); free_percpu(intel_idle_cpuidle_devices); return retval; } } __register_cpu_notifier(&cpu_hotplug_notifier); if (boot_cpu_has(X86_FEATURE_ARAT)) /* Always Reliable APIC Timer */ lapic_timer_reliable_states = LAPIC_TIMER_ALWAYS_RELIABLE; else on_each_cpu(__setup_broadcast_timer, (void *)true, 1); cpu_notifier_register_done(); pr_debug(PREFIX "lapic_timer_reliable_states 0x%x\n", lapic_timer_reliable_states); return 0; } device_initcall(intel_idle_init); /* * We are not really modular, but we used to support that. Meaning we also * support "intel_idle.max_cstate=..." at boot and also a read-only export of * it at /sys/module/intel_idle/parameters/max_cstate -- so using module_param * is the easiest way (currently) to continue doing that. */ module_param(max_cstate, int, 0444);