// SPDX-License-Identifier: GPL-2.0-only /* * intel_idle.c - native hardware idle loop for modern Intel processors * * Copyright (c) 2013, Intel Corporation. * Len Brown */ /* * 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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include #include #include #include #include #include #include #include #include #include #include #include #include #define INTEL_IDLE_VERSION "0.4.1" 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; bool use_acpi; }; 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_s2idle(struct cpuidle_device *dev, struct cpuidle_driver *drv, int index); static struct cpuidle_state *cpuidle_state_table; /* * Enable this state by default even if the ACPI _CST does not list it. */ #define CPUIDLE_FLAG_ALWAYS_ENABLE BIT(15) /* * 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", .desc = "MWAIT 0x00", .flags = MWAIT2flg(0x00), .exit_latency = 3, .target_residency = 6, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C1E", .desc = "MWAIT 0x01", .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE, .exit_latency = 10, .target_residency = 20, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C3", .desc = "MWAIT 0x10", .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 20, .target_residency = 80, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C6", .desc = "MWAIT 0x20", .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 200, .target_residency = 800, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .enter = NULL } }; static struct cpuidle_state snb_cstates[] = { { .name = "C1", .desc = "MWAIT 0x00", .flags = MWAIT2flg(0x00), .exit_latency = 2, .target_residency = 2, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C1E", .desc = "MWAIT 0x01", .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE, .exit_latency = 10, .target_residency = 20, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C3", .desc = "MWAIT 0x10", .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 80, .target_residency = 211, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C6", .desc = "MWAIT 0x20", .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 104, .target_residency = 345, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C7", .desc = "MWAIT 0x30", .flags = MWAIT2flg(0x30) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 109, .target_residency = 345, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .enter = NULL } }; static struct cpuidle_state byt_cstates[] = { { .name = "C1", .desc = "MWAIT 0x00", .flags = MWAIT2flg(0x00), .exit_latency = 1, .target_residency = 1, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C6N", .desc = "MWAIT 0x58", .flags = MWAIT2flg(0x58) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 300, .target_residency = 275, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C6S", .desc = "MWAIT 0x52", .flags = MWAIT2flg(0x52) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 500, .target_residency = 560, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C7", .desc = "MWAIT 0x60", .flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 1200, .target_residency = 4000, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C7S", .desc = "MWAIT 0x64", .flags = MWAIT2flg(0x64) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 10000, .target_residency = 20000, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .enter = NULL } }; static struct cpuidle_state cht_cstates[] = { { .name = "C1", .desc = "MWAIT 0x00", .flags = MWAIT2flg(0x00), .exit_latency = 1, .target_residency = 1, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C6N", .desc = "MWAIT 0x58", .flags = MWAIT2flg(0x58) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 80, .target_residency = 275, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C6S", .desc = "MWAIT 0x52", .flags = MWAIT2flg(0x52) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 200, .target_residency = 560, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C7", .desc = "MWAIT 0x60", .flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 1200, .target_residency = 4000, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C7S", .desc = "MWAIT 0x64", .flags = MWAIT2flg(0x64) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 10000, .target_residency = 20000, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .enter = NULL } }; static struct cpuidle_state ivb_cstates[] = { { .name = "C1", .desc = "MWAIT 0x00", .flags = MWAIT2flg(0x00), .exit_latency = 1, .target_residency = 1, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C1E", .desc = "MWAIT 0x01", .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE, .exit_latency = 10, .target_residency = 20, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C3", .desc = "MWAIT 0x10", .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 59, .target_residency = 156, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C6", .desc = "MWAIT 0x20", .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 80, .target_residency = 300, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C7", .desc = "MWAIT 0x30", .flags = MWAIT2flg(0x30) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 87, .target_residency = 300, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .enter = NULL } }; static struct cpuidle_state ivt_cstates[] = { { .name = "C1", .desc = "MWAIT 0x00", .flags = MWAIT2flg(0x00), .exit_latency = 1, .target_residency = 1, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C1E", .desc = "MWAIT 0x01", .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE, .exit_latency = 10, .target_residency = 80, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C3", .desc = "MWAIT 0x10", .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 59, .target_residency = 156, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C6", .desc = "MWAIT 0x20", .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 82, .target_residency = 300, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .enter = NULL } }; static struct cpuidle_state ivt_cstates_4s[] = { { .name = "C1", .desc = "MWAIT 0x00", .flags = MWAIT2flg(0x00), .exit_latency = 1, .target_residency = 1, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C1E", .desc = "MWAIT 0x01", .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE, .exit_latency = 10, .target_residency = 250, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C3", .desc = "MWAIT 0x10", .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 59, .target_residency = 300, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C6", .desc = "MWAIT 0x20", .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 84, .target_residency = 400, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .enter = NULL } }; static struct cpuidle_state ivt_cstates_8s[] = { { .name = "C1", .desc = "MWAIT 0x00", .flags = MWAIT2flg(0x00), .exit_latency = 1, .target_residency = 1, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C1E", .desc = "MWAIT 0x01", .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE, .exit_latency = 10, .target_residency = 500, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C3", .desc = "MWAIT 0x10", .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 59, .target_residency = 600, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C6", .desc = "MWAIT 0x20", .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 88, .target_residency = 700, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .enter = NULL } }; static struct cpuidle_state hsw_cstates[] = { { .name = "C1", .desc = "MWAIT 0x00", .flags = MWAIT2flg(0x00), .exit_latency = 2, .target_residency = 2, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C1E", .desc = "MWAIT 0x01", .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE, .exit_latency = 10, .target_residency = 20, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C3", .desc = "MWAIT 0x10", .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 33, .target_residency = 100, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C6", .desc = "MWAIT 0x20", .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 133, .target_residency = 400, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C7s", .desc = "MWAIT 0x32", .flags = MWAIT2flg(0x32) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 166, .target_residency = 500, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C8", .desc = "MWAIT 0x40", .flags = MWAIT2flg(0x40) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 300, .target_residency = 900, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C9", .desc = "MWAIT 0x50", .flags = MWAIT2flg(0x50) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 600, .target_residency = 1800, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C10", .desc = "MWAIT 0x60", .flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 2600, .target_residency = 7700, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .enter = NULL } }; static struct cpuidle_state bdw_cstates[] = { { .name = "C1", .desc = "MWAIT 0x00", .flags = MWAIT2flg(0x00), .exit_latency = 2, .target_residency = 2, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C1E", .desc = "MWAIT 0x01", .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE, .exit_latency = 10, .target_residency = 20, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C3", .desc = "MWAIT 0x10", .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 40, .target_residency = 100, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C6", .desc = "MWAIT 0x20", .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 133, .target_residency = 400, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C7s", .desc = "MWAIT 0x32", .flags = MWAIT2flg(0x32) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 166, .target_residency = 500, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C8", .desc = "MWAIT 0x40", .flags = MWAIT2flg(0x40) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 300, .target_residency = 900, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C9", .desc = "MWAIT 0x50", .flags = MWAIT2flg(0x50) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 600, .target_residency = 1800, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C10", .desc = "MWAIT 0x60", .flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 2600, .target_residency = 7700, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .enter = NULL } }; static struct cpuidle_state skl_cstates[] = { { .name = "C1", .desc = "MWAIT 0x00", .flags = MWAIT2flg(0x00), .exit_latency = 2, .target_residency = 2, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C1E", .desc = "MWAIT 0x01", .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE, .exit_latency = 10, .target_residency = 20, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C3", .desc = "MWAIT 0x10", .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 70, .target_residency = 100, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C6", .desc = "MWAIT 0x20", .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 85, .target_residency = 200, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C7s", .desc = "MWAIT 0x33", .flags = MWAIT2flg(0x33) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 124, .target_residency = 800, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C8", .desc = "MWAIT 0x40", .flags = MWAIT2flg(0x40) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 200, .target_residency = 800, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C9", .desc = "MWAIT 0x50", .flags = MWAIT2flg(0x50) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 480, .target_residency = 5000, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C10", .desc = "MWAIT 0x60", .flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 890, .target_residency = 5000, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .enter = NULL } }; static struct cpuidle_state skx_cstates[] = { { .name = "C1", .desc = "MWAIT 0x00", .flags = MWAIT2flg(0x00), .exit_latency = 2, .target_residency = 2, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C1E", .desc = "MWAIT 0x01", .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE, .exit_latency = 10, .target_residency = 20, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C6", .desc = "MWAIT 0x20", .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 133, .target_residency = 600, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .enter = NULL } }; static struct cpuidle_state atom_cstates[] = { { .name = "C1E", .desc = "MWAIT 0x00", .flags = MWAIT2flg(0x00), .exit_latency = 10, .target_residency = 20, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C2", .desc = "MWAIT 0x10", .flags = MWAIT2flg(0x10), .exit_latency = 20, .target_residency = 80, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C4", .desc = "MWAIT 0x30", .flags = MWAIT2flg(0x30) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 100, .target_residency = 400, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C6", .desc = "MWAIT 0x52", .flags = MWAIT2flg(0x52) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 140, .target_residency = 560, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .enter = NULL } }; static struct cpuidle_state tangier_cstates[] = { { .name = "C1", .desc = "MWAIT 0x00", .flags = MWAIT2flg(0x00), .exit_latency = 1, .target_residency = 4, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C4", .desc = "MWAIT 0x30", .flags = MWAIT2flg(0x30) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 100, .target_residency = 400, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C6", .desc = "MWAIT 0x52", .flags = MWAIT2flg(0x52) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 140, .target_residency = 560, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C7", .desc = "MWAIT 0x60", .flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 1200, .target_residency = 4000, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C9", .desc = "MWAIT 0x64", .flags = MWAIT2flg(0x64) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 10000, .target_residency = 20000, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .enter = NULL } }; static struct cpuidle_state avn_cstates[] = { { .name = "C1", .desc = "MWAIT 0x00", .flags = MWAIT2flg(0x00), .exit_latency = 2, .target_residency = 2, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C6", .desc = "MWAIT 0x51", .flags = MWAIT2flg(0x51) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 15, .target_residency = 45, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .enter = NULL } }; static struct cpuidle_state knl_cstates[] = { { .name = "C1", .desc = "MWAIT 0x00", .flags = MWAIT2flg(0x00), .exit_latency = 1, .target_residency = 2, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle }, { .name = "C6", .desc = "MWAIT 0x10", .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 120, .target_residency = 500, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle }, { .enter = NULL } }; static struct cpuidle_state bxt_cstates[] = { { .name = "C1", .desc = "MWAIT 0x00", .flags = MWAIT2flg(0x00), .exit_latency = 2, .target_residency = 2, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C1E", .desc = "MWAIT 0x01", .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE, .exit_latency = 10, .target_residency = 20, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C6", .desc = "MWAIT 0x20", .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 133, .target_residency = 133, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C7s", .desc = "MWAIT 0x31", .flags = MWAIT2flg(0x31) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 155, .target_residency = 155, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C8", .desc = "MWAIT 0x40", .flags = MWAIT2flg(0x40) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 1000, .target_residency = 1000, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C9", .desc = "MWAIT 0x50", .flags = MWAIT2flg(0x50) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 2000, .target_residency = 2000, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C10", .desc = "MWAIT 0x60", .flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 10000, .target_residency = 10000, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .enter = NULL } }; static struct cpuidle_state dnv_cstates[] = { { .name = "C1", .desc = "MWAIT 0x00", .flags = MWAIT2flg(0x00), .exit_latency = 2, .target_residency = 2, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C1E", .desc = "MWAIT 0x01", .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE, .exit_latency = 10, .target_residency = 20, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .name = "C6", .desc = "MWAIT 0x20", .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 50, .target_residency = 500, .enter = &intel_idle, .enter_s2idle = intel_idle_s2idle, }, { .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; bool uninitialized_var(tick); int cpu = smp_processor_id(); /* * 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 (!static_cpu_has(X86_FEATURE_ARAT)) { cstate = (((eax) >> MWAIT_SUBSTATE_SIZE) & MWAIT_CSTATE_MASK) + 1; tick = false; if (!(lapic_timer_reliable_states & (1 << (cstate)))) { tick = true; tick_broadcast_enter(); } } mwait_idle_with_hints(eax, ecx); if (!static_cpu_has(X86_FEATURE_ARAT) && tick) tick_broadcast_exit(); return index; } /** * intel_idle_s2idle - simplified "enter" callback routine for suspend-to-idle * @dev: cpuidle_device * @drv: cpuidle driver * @index: state index */ static void intel_idle_s2idle(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 bool intel_idle_verify_cstate(unsigned int mwait_hint) { unsigned int mwait_cstate = MWAIT_HINT2CSTATE(mwait_hint) + 1; unsigned int num_substates = (mwait_substates >> mwait_cstate * 4) & MWAIT_SUBSTATE_MASK; /* Ignore the C-state if there are NO sub-states in CPUID for it. */ if (num_substates == 0) return false; if (mwait_cstate > 2 && !boot_cpu_has(X86_FEATURE_NONSTOP_TSC)) mark_tsc_unstable("TSC halts in idle states deeper than C2"); return true; } static void auto_demotion_disable(void) { unsigned long long msr_bits; rdmsrl(MSR_PKG_CST_CONFIG_CONTROL, msr_bits); msr_bits &= ~(icpu->auto_demotion_disable_flags); wrmsrl(MSR_PKG_CST_CONFIG_CONTROL, msr_bits); } static void c1e_promotion_disable(void) { 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_nhx = { .state_table = nehalem_cstates, .auto_demotion_disable_flags = NHM_C1_AUTO_DEMOTE | NHM_C3_AUTO_DEMOTE, .disable_promotion_to_c1e = true, .use_acpi = 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_snx = { .state_table = snb_cstates, .disable_promotion_to_c1e = true, .use_acpi = 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, .use_acpi = 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_hsx = { .state_table = hsw_cstates, .disable_promotion_to_c1e = true, .use_acpi = 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_bdx = { .state_table = bdw_cstates, .disable_promotion_to_c1e = true, .use_acpi = 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, .use_acpi = true, }; static const struct idle_cpu idle_cpu_avn = { .state_table = avn_cstates, .disable_promotion_to_c1e = true, .use_acpi = true, }; static const struct idle_cpu idle_cpu_knl = { .state_table = knl_cstates, .use_acpi = true, }; 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, .use_acpi = true, }; static const struct x86_cpu_id intel_idle_ids[] __initconst = { INTEL_CPU_FAM6(NEHALEM_EP, idle_cpu_nhx), INTEL_CPU_FAM6(NEHALEM, idle_cpu_nehalem), INTEL_CPU_FAM6(NEHALEM_G, idle_cpu_nehalem), INTEL_CPU_FAM6(WESTMERE, idle_cpu_nehalem), INTEL_CPU_FAM6(WESTMERE_EP, idle_cpu_nhx), INTEL_CPU_FAM6(NEHALEM_EX, idle_cpu_nhx), INTEL_CPU_FAM6(ATOM_BONNELL, idle_cpu_atom), INTEL_CPU_FAM6(ATOM_BONNELL_MID, idle_cpu_lincroft), INTEL_CPU_FAM6(WESTMERE_EX, idle_cpu_nhx), INTEL_CPU_FAM6(SANDYBRIDGE, idle_cpu_snb), INTEL_CPU_FAM6(SANDYBRIDGE_X, idle_cpu_snx), INTEL_CPU_FAM6(ATOM_SALTWELL, idle_cpu_atom), INTEL_CPU_FAM6(ATOM_SILVERMONT, idle_cpu_byt), INTEL_CPU_FAM6(ATOM_SILVERMONT_MID, idle_cpu_tangier), INTEL_CPU_FAM6(ATOM_AIRMONT, idle_cpu_cht), INTEL_CPU_FAM6(IVYBRIDGE, idle_cpu_ivb), INTEL_CPU_FAM6(IVYBRIDGE_X, idle_cpu_ivt), INTEL_CPU_FAM6(HASWELL, idle_cpu_hsw), INTEL_CPU_FAM6(HASWELL_X, idle_cpu_hsx), INTEL_CPU_FAM6(HASWELL_L, idle_cpu_hsw), INTEL_CPU_FAM6(HASWELL_G, idle_cpu_hsw), INTEL_CPU_FAM6(ATOM_SILVERMONT_D, idle_cpu_avn), INTEL_CPU_FAM6(BROADWELL, idle_cpu_bdw), INTEL_CPU_FAM6(BROADWELL_G, idle_cpu_bdw), INTEL_CPU_FAM6(BROADWELL_X, idle_cpu_bdx), INTEL_CPU_FAM6(BROADWELL_D, idle_cpu_bdx), INTEL_CPU_FAM6(SKYLAKE_L, idle_cpu_skl), INTEL_CPU_FAM6(SKYLAKE, idle_cpu_skl), INTEL_CPU_FAM6(KABYLAKE_L, idle_cpu_skl), INTEL_CPU_FAM6(KABYLAKE, idle_cpu_skl), INTEL_CPU_FAM6(SKYLAKE_X, idle_cpu_skx), INTEL_CPU_FAM6(XEON_PHI_KNL, idle_cpu_knl), INTEL_CPU_FAM6(XEON_PHI_KNM, idle_cpu_knl), INTEL_CPU_FAM6(ATOM_GOLDMONT, idle_cpu_bxt), INTEL_CPU_FAM6(ATOM_GOLDMONT_PLUS, idle_cpu_bxt), INTEL_CPU_FAM6(ATOM_GOLDMONT_D, idle_cpu_dnv), INTEL_CPU_FAM6(ATOM_TREMONT_D, idle_cpu_dnv), {} }; #define INTEL_CPU_FAM6_MWAIT \ { X86_VENDOR_INTEL, 6, X86_MODEL_ANY, X86_FEATURE_MWAIT, 0 } static const struct x86_cpu_id intel_mwait_ids[] __initconst = { INTEL_CPU_FAM6_MWAIT, {} }; static bool intel_idle_max_cstate_reached(int cstate) { if (cstate + 1 > max_cstate) { pr_info("max_cstate %d reached\n", max_cstate); return true; } return false; } #ifdef CONFIG_ACPI_PROCESSOR_CSTATE #include static bool no_acpi __read_mostly; module_param(no_acpi, bool, 0444); MODULE_PARM_DESC(no_acpi, "Do not use ACPI _CST for building the idle states list"); static struct acpi_processor_power acpi_state_table; /** * intel_idle_cst_usable - Check if the _CST information can be used. * * Check if all of the C-states listed by _CST in the max_cstate range are * ACPI_CSTATE_FFH, which means that they should be entered via MWAIT. */ static bool intel_idle_cst_usable(void) { int cstate, limit; limit = min_t(int, min_t(int, CPUIDLE_STATE_MAX, max_cstate + 1), acpi_state_table.count); for (cstate = 1; cstate < limit; cstate++) { struct acpi_processor_cx *cx = &acpi_state_table.states[cstate]; if (cx->entry_method != ACPI_CSTATE_FFH) return false; } return true; } static bool intel_idle_acpi_cst_extract(void) { unsigned int cpu; if (no_acpi) { pr_debug("Not allowed to use ACPI _CST\n"); return false; } for_each_possible_cpu(cpu) { struct acpi_processor *pr = per_cpu(processors, cpu); if (!pr) continue; if (acpi_processor_evaluate_cst(pr->handle, cpu, &acpi_state_table)) continue; acpi_state_table.count++; if (!intel_idle_cst_usable()) continue; if (!acpi_processor_claim_cst_control()) { acpi_state_table.count = 0; return false; } return true; } pr_debug("ACPI _CST not found or not usable\n"); return false; } static void intel_idle_init_cstates_acpi(struct cpuidle_driver *drv) { int cstate, limit = min_t(int, CPUIDLE_STATE_MAX, acpi_state_table.count); /* * If limit > 0, intel_idle_cst_usable() has returned 'true', so all of * the interesting states are ACPI_CSTATE_FFH. */ for (cstate = 1; cstate < limit; cstate++) { struct acpi_processor_cx *cx; struct cpuidle_state *state; if (intel_idle_max_cstate_reached(cstate)) break; cx = &acpi_state_table.states[cstate]; state = &drv->states[drv->state_count++]; snprintf(state->name, CPUIDLE_NAME_LEN, "C%d_ACPI", cstate); strlcpy(state->desc, cx->desc, CPUIDLE_DESC_LEN); state->exit_latency = cx->latency; /* * For C1-type C-states use the same number for both the exit * latency and target residency, because that is the case for * C1 in the majority of the static C-states tables above. * For the other types of C-states, however, set the target * residency to 3 times the exit latency which should lead to * a reasonable balance between energy-efficiency and * performance in the majority of interesting cases. */ state->target_residency = cx->latency; if (cx->type > ACPI_STATE_C1) state->target_residency *= 3; state->flags = MWAIT2flg(cx->address); if (cx->type > ACPI_STATE_C2) state->flags |= CPUIDLE_FLAG_TLB_FLUSHED; state->enter = intel_idle; state->enter_s2idle = intel_idle_s2idle; } } static bool intel_idle_off_by_default(u32 mwait_hint) { int cstate, limit; /* * If there are no _CST C-states, do not disable any C-states by * default. */ if (!acpi_state_table.count) return false; limit = min_t(int, CPUIDLE_STATE_MAX, acpi_state_table.count); /* * If limit > 0, intel_idle_cst_usable() has returned 'true', so all of * the interesting states are ACPI_CSTATE_FFH. */ for (cstate = 1; cstate < limit; cstate++) { if (acpi_state_table.states[cstate].address == mwait_hint) return false; } return true; } #else /* !CONFIG_ACPI_PROCESSOR_CSTATE */ static inline bool intel_idle_acpi_cst_extract(void) { return false; } static inline void intel_idle_init_cstates_acpi(struct cpuidle_driver *drv) { } static inline bool intel_idle_off_by_default(u32 mwait_hint) { return false; } #endif /* !CONFIG_ACPI_PROCESSOR_CSTATE */ /* * 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_PKG_CST_CONFIG_CONTROL, 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].flags |= CPUIDLE_FLAG_UNUSABLE; /* C8-SKL */ skl_cstates[6].flags |= CPUIDLE_FLAG_UNUSABLE; /* C9-SKL */ } static void intel_idle_init_cstates_icpu(struct cpuidle_driver *drv) { int cstate; switch (boot_cpu_data.x86_model) { case INTEL_FAM6_IVYBRIDGE_X: ivt_idle_state_table_update(); break; case INTEL_FAM6_ATOM_GOLDMONT: case INTEL_FAM6_ATOM_GOLDMONT_PLUS: bxt_idle_state_table_update(); break; case INTEL_FAM6_SKYLAKE: sklh_idle_state_table_update(); break; } for (cstate = 0; cstate < CPUIDLE_STATE_MAX; ++cstate) { unsigned int mwait_hint; if (intel_idle_max_cstate_reached(cstate)) break; if (!cpuidle_state_table[cstate].enter && !cpuidle_state_table[cstate].enter_s2idle) break; /* If marked as unusable, skip this state. */ if (cpuidle_state_table[cstate].flags & CPUIDLE_FLAG_UNUSABLE) { pr_debug("state %s is disabled\n", cpuidle_state_table[cstate].name); continue; } mwait_hint = flg2MWAIT(cpuidle_state_table[cstate].flags); if (!intel_idle_verify_cstate(mwait_hint)) continue; /* Structure copy. */ drv->states[drv->state_count] = cpuidle_state_table[cstate]; if (icpu->use_acpi && intel_idle_off_by_default(mwait_hint) && !(cpuidle_state_table[cstate].flags & CPUIDLE_FLAG_ALWAYS_ENABLE)) drv->states[drv->state_count].flags |= CPUIDLE_FLAG_OFF; drv->state_count++; } if (icpu->byt_auto_demotion_disable_flag) { wrmsrl(MSR_CC6_DEMOTION_POLICY_CONFIG, 0); wrmsrl(MSR_MC6_DEMOTION_POLICY_CONFIG, 0); } } /* * intel_idle_cpuidle_driver_init() * allocate, initialize cpuidle_states */ static void __init intel_idle_cpuidle_driver_init(struct cpuidle_driver *drv) { cpuidle_poll_state_init(drv); drv->state_count = 1; if (icpu) intel_idle_init_cstates_icpu(drv); else intel_idle_init_cstates_acpi(drv); } /* * intel_idle_cpu_init() * allocate, initialize, register cpuidle_devices * @cpu: cpu/core to initialize */ static int intel_idle_cpu_init(unsigned 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("cpuidle_register_device %d failed!\n", cpu); return -EIO; } if (!icpu) return 0; if (icpu->auto_demotion_disable_flags) auto_demotion_disable(); if (icpu->disable_promotion_to_c1e) c1e_promotion_disable(); return 0; } static int intel_idle_cpu_online(unsigned int cpu) { struct cpuidle_device *dev; if (lapic_timer_reliable_states != LAPIC_TIMER_ALWAYS_RELIABLE) tick_broadcast_enable(); /* * 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, cpu); if (!dev->registered) return intel_idle_cpu_init(cpu); return 0; } /** * intel_idle_cpuidle_devices_uninit - Unregister all cpuidle devices. */ static void __init intel_idle_cpuidle_devices_uninit(void) { int i; for_each_online_cpu(i) cpuidle_unregister_device(per_cpu_ptr(intel_idle_cpuidle_devices, i)); } static int __init intel_idle_init(void) { const struct x86_cpu_id *id; unsigned int eax, ebx, ecx; int retval; /* Do not load intel_idle at all for now if idle= is passed */ if (boot_option_idle_override != IDLE_NO_OVERRIDE) return -ENODEV; if (max_cstate == 0) { pr_debug("disabled\n"); return -EPERM; } id = x86_match_cpu(intel_idle_ids); if (id) { if (!boot_cpu_has(X86_FEATURE_MWAIT)) { pr_debug("Please enable MWAIT in BIOS SETUP\n"); return -ENODEV; } } else { id = x86_match_cpu(intel_mwait_ids); if (!id) 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("MWAIT substates: 0x%x\n", mwait_substates); icpu = (const struct idle_cpu *)id->driver_data; if (icpu) { cpuidle_state_table = icpu->state_table; if (icpu->use_acpi) intel_idle_acpi_cst_extract(); } else if (!intel_idle_acpi_cst_extract()) { return -ENODEV; } pr_debug("v" INTEL_IDLE_VERSION " model 0x%X\n", boot_cpu_data.x86_model); intel_idle_cpuidle_devices = alloc_percpu(struct cpuidle_device); if (!intel_idle_cpuidle_devices) return -ENOMEM; intel_idle_cpuidle_driver_init(&intel_idle_driver); retval = cpuidle_register_driver(&intel_idle_driver); if (retval) { struct cpuidle_driver *drv = cpuidle_get_driver(); printk(KERN_DEBUG pr_fmt("intel_idle yielding to %s\n"), drv ? drv->name : "none"); goto init_driver_fail; } if (boot_cpu_has(X86_FEATURE_ARAT)) /* Always Reliable APIC Timer */ lapic_timer_reliable_states = LAPIC_TIMER_ALWAYS_RELIABLE; retval = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "idle/intel:online", intel_idle_cpu_online, NULL); if (retval < 0) goto hp_setup_fail; pr_debug("lapic_timer_reliable_states 0x%x\n", lapic_timer_reliable_states); return 0; hp_setup_fail: intel_idle_cpuidle_devices_uninit(); cpuidle_unregister_driver(&intel_idle_driver); init_driver_fail: free_percpu(intel_idle_cpuidle_devices); return retval; } 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);