--- /dev/null
+/*
+ * intel_idle.c - native hardware idle loop for modern Intel processors
+ *
+ * Copyright (c) 2013, Intel Corporation.
+ * Len Brown <len.brown@intel.com>
+ *
+ * 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.
+ *
+ * There is currently no kernel-based automatic probing/loading mechanism
+ * if the driver is built as a module.
+ */
+
+/* un-comment DEBUG to enable pr_debug() statements */
+#define DEBUG
+
+#include <linux/kernel.h>
+#include <linux/cpuidle.h>
+#include <linux/tick.h>
+#include <trace/events/power.h>
+#include <linux/sched.h>
+#include <linux/notifier.h>
+#include <linux/cpu.h>
+#include <linux/module.h>
+#include <asm/cpu_device_id.h>
+#include <asm/mwait.h>
+#include <asm/msr.h>
+
+#define INTEL_IDLE_VERSION "0.4"
+#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 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 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 }
+};
+
+/**
+ * intel_idle
+ * @dev: cpuidle_device
+ * @drv: cpuidle driver
+ * @index: index of cpuidle state
+ *
+ * Must be called under local_irq_disable().
+ */
+static 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)
+ intel_idle_cpu_init(hotcpu);
+
+ 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_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_avn = {
+ .state_table = avn_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(0x1a, idle_cpu_nehalem),
+ ICPU(0x1e, idle_cpu_nehalem),
+ ICPU(0x1f, idle_cpu_nehalem),
+ ICPU(0x25, idle_cpu_nehalem),
+ ICPU(0x2c, idle_cpu_nehalem),
+ ICPU(0x2e, idle_cpu_nehalem),
+ ICPU(0x1c, idle_cpu_atom),
+ ICPU(0x26, idle_cpu_lincroft),
+ ICPU(0x2f, idle_cpu_nehalem),
+ ICPU(0x2a, idle_cpu_snb),
+ ICPU(0x2d, idle_cpu_snb),
+ ICPU(0x36, idle_cpu_atom),
+ ICPU(0x37, idle_cpu_byt),
+ ICPU(0x4c, idle_cpu_cht),
+ ICPU(0x3a, idle_cpu_ivb),
+ ICPU(0x3e, idle_cpu_ivt),
+ ICPU(0x3c, idle_cpu_hsw),
+ ICPU(0x3f, idle_cpu_hsw),
+ ICPU(0x45, idle_cpu_hsw),
+ ICPU(0x46, idle_cpu_hsw),
+ ICPU(0x4d, idle_cpu_avn),
+ ICPU(0x3d, idle_cpu_bdw),
+ ICPU(0x47, idle_cpu_bdw),
+ ICPU(0x4f, idle_cpu_bdw),
+ ICPU(0x56, idle_cpu_bdw),
+ {}
+};
+MODULE_DEVICE_TABLE(x86cpu, intel_idle_ids);
+
+/*
+ * 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;
+
+ 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);
+
+ pr_debug(PREFIX "v" INTEL_IDLE_VERSION
+ " model 0x%X\n", boot_cpu_data.x86_model);
+
+ pr_debug(PREFIX "lapic_timer_reliable_states 0x%x\n",
+ lapic_timer_reliable_states);
+ return 0;
+}
+
+/*
+ * intel_idle_cpuidle_devices_uninit()
+ * unregister, free 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);
+ }
+
+ free_percpu(intel_idle_cpuidle_devices);
+ return;
+}
+
+/*
+ * intel_idle_state_table_update()
+ *
+ * Update the default state_table for this CPU-id
+ *
+ * Currently used to access tuned IVT multi-socket targets
+ * Assumption: num_sockets == (max_package_num + 1)
+ */
+void intel_idle_state_table_update(void)
+{
+ /* IVT uses a different table for 1-2, 3-4, and > 4 sockets */
+ if (boot_cpu_data.x86_model == 0x3e) { /* IVT */
+ 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 */
+ }
+ return;
+}
+
+/*
+ * intel_idle_cpuidle_driver_init()
+ * allocate, initialize cpuidle_states
+ */
+static int __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)
+ 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 (((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->auto_demotion_disable_flags)
+ on_each_cpu(auto_demotion_disable, NULL, 1);
+
+ if (icpu->byt_auto_demotion_disable_flag) {
+ wrmsrl(MSR_CC6_DEMOTION_POLICY_CONFIG, 0);
+ wrmsrl(MSR_MC6_DEMOTION_POLICY_CONFIG, 0);
+ }
+
+ if (icpu->disable_promotion_to_c1e) /* each-cpu is redundant */
+ on_each_cpu(c1e_promotion_disable, NULL, 1);
+
+ return 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);
+ intel_idle_cpuidle_devices_uninit();
+ 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_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");
+ return retval;
+ }
+
+ intel_idle_cpuidle_devices = alloc_percpu(struct cpuidle_device);
+ if (intel_idle_cpuidle_devices == NULL)
+ return -ENOMEM;
+
+ cpu_notifier_register_begin();
+
+ for_each_online_cpu(i) {
+ retval = intel_idle_cpu_init(i);
+ if (retval) {
+ cpu_notifier_register_done();
+ cpuidle_unregister_driver(&intel_idle_driver);
+ return retval;
+ }
+ }
+ __register_cpu_notifier(&cpu_hotplug_notifier);
+
+ cpu_notifier_register_done();
+
+ return 0;
+}
+
+static void __exit intel_idle_exit(void)
+{
+ intel_idle_cpuidle_devices_uninit();
+ cpuidle_unregister_driver(&intel_idle_driver);
+
+ cpu_notifier_register_begin();
+
+ if (lapic_timer_reliable_states != LAPIC_TIMER_ALWAYS_RELIABLE)
+ on_each_cpu(__setup_broadcast_timer, (void *)false, 1);
+ __unregister_cpu_notifier(&cpu_hotplug_notifier);
+
+ cpu_notifier_register_done();
+
+ return;
+}
+
+module_init(intel_idle_init);
+module_exit(intel_idle_exit);
+
+module_param(max_cstate, int, 0444);
+
+MODULE_AUTHOR("Len Brown <len.brown@intel.com>");
+MODULE_DESCRIPTION("Cpuidle driver for Intel Hardware v" INTEL_IDLE_VERSION);
+MODULE_LICENSE("GPL");
Code Review / kvmfornfv.git / blobdiff