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linux_dsm_epyc7002/drivers/idle/intel_idle.c
David E. Box 1b2e87687d x86/intel_idle: add Gemini Lake support 
Gemini Lake uses the same C-states as Broxton and also uses the
IRTL MSR's to determine maximum C-state latency.

Signed-off-by: David E. Box <david.e.box@linux.intel.com>
Acked-by: Len Brown <len.brown@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-05-01 23:17:37 +02:00

1485 lines
36 KiB
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/*
* 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.
*
*/
/* 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/moduleparam.h>
#include <asm/cpu_device_id.h>
#include <asm/intel-family.h>
#include <asm/mwait.h>
#include <asm/msr.h>
#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 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",
.desc = "MWAIT 0x00",
.flags = MWAIT2flg(0x00),
.exit_latency = 3,
.target_residency = 6,
.enter = &intel_idle,
.enter_freeze = intel_idle_freeze, },
{
.name = "C1E",
.desc = "MWAIT 0x01",
.flags = MWAIT2flg(0x01),
.exit_latency = 10,
.target_residency = 20,
.enter = &intel_idle,
.enter_freeze = intel_idle_freeze, },
{
.name = "C3",
.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",
.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",
.desc = "MWAIT 0x00",
.flags = MWAIT2flg(0x00),
.exit_latency = 2,
.target_residency = 2,
.enter = &intel_idle,
.enter_freeze = intel_idle_freeze, },
{
.name = "C1E",
.desc = "MWAIT 0x01",
.flags = MWAIT2flg(0x01),
.exit_latency = 10,
.target_residency = 20,
.enter = &intel_idle,
.enter_freeze = intel_idle_freeze, },
{
.name = "C3",
.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",
.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",
.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",
.desc = "MWAIT 0x00",
.flags = MWAIT2flg(0x00),
.exit_latency = 1,
.target_residency = 1,
.enter = &intel_idle,
.enter_freeze = intel_idle_freeze, },
{
.name = "C6N",
.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",
.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",
.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",
.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",
.desc = "MWAIT 0x00",
.flags = MWAIT2flg(0x00),
.exit_latency = 1,
.target_residency = 1,
.enter = &intel_idle,
.enter_freeze = intel_idle_freeze, },
{
.name = "C6N",
.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",
.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",
.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",
.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",
.desc = "MWAIT 0x00",
.flags = MWAIT2flg(0x00),
.exit_latency = 1,
.target_residency = 1,
.enter = &intel_idle,
.enter_freeze = intel_idle_freeze, },
{
.name = "C1E",
.desc = "MWAIT 0x01",
.flags = MWAIT2flg(0x01),
.exit_latency = 10,
.target_residency = 20,
.enter = &intel_idle,
.enter_freeze = intel_idle_freeze, },
{
.name = "C3",
.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",
.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",
.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",
.desc = "MWAIT 0x00",
.flags = MWAIT2flg(0x00),
.exit_latency = 1,
.target_residency = 1,
.enter = &intel_idle,
.enter_freeze = intel_idle_freeze, },
{
.name = "C1E",
.desc = "MWAIT 0x01",
.flags = MWAIT2flg(0x01),
.exit_latency = 10,
.target_residency = 80,
.enter = &intel_idle,
.enter_freeze = intel_idle_freeze, },
{
.name = "C3",
.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",
.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",
.desc = "MWAIT 0x00",
.flags = MWAIT2flg(0x00),
.exit_latency = 1,
.target_residency = 1,
.enter = &intel_idle,
.enter_freeze = intel_idle_freeze, },
{
.name = "C1E",
.desc = "MWAIT 0x01",
.flags = MWAIT2flg(0x01),
.exit_latency = 10,
.target_residency = 250,
.enter = &intel_idle,
.enter_freeze = intel_idle_freeze, },
{
.name = "C3",
.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",
.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",
.desc = "MWAIT 0x00",
.flags = MWAIT2flg(0x00),
.exit_latency = 1,
.target_residency = 1,
.enter = &intel_idle,
.enter_freeze = intel_idle_freeze, },
{
.name = "C1E",
.desc = "MWAIT 0x01",
.flags = MWAIT2flg(0x01),
.exit_latency = 10,
.target_residency = 500,
.enter = &intel_idle,
.enter_freeze = intel_idle_freeze, },
{
.name = "C3",
.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",
.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",
.desc = "MWAIT 0x00",
.flags = MWAIT2flg(0x00),
.exit_latency = 2,
.target_residency = 2,
.enter = &intel_idle,
.enter_freeze = intel_idle_freeze, },
{
.name = "C1E",
.desc = "MWAIT 0x01",
.flags = MWAIT2flg(0x01),
.exit_latency = 10,
.target_residency = 20,
.enter = &intel_idle,
.enter_freeze = intel_idle_freeze, },
{
.name = "C3",
.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",
.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",
.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",
.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",
.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",
.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",
.desc = "MWAIT 0x00",
.flags = MWAIT2flg(0x00),
.exit_latency = 2,
.target_residency = 2,
.enter = &intel_idle,
.enter_freeze = intel_idle_freeze, },
{
.name = "C1E",
.desc = "MWAIT 0x01",
.flags = MWAIT2flg(0x01),
.exit_latency = 10,
.target_residency = 20,
.enter = &intel_idle,
.enter_freeze = intel_idle_freeze, },
{
.name = "C3",
.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",
.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",
.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",
.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",
.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",
.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",
.desc = "MWAIT 0x00",
.flags = MWAIT2flg(0x00),
.exit_latency = 2,
.target_residency = 2,
.enter = &intel_idle,
.enter_freeze = intel_idle_freeze, },
{
.name = "C1E",
.desc = "MWAIT 0x01",
.flags = MWAIT2flg(0x01),
.exit_latency = 10,
.target_residency = 20,
.enter = &intel_idle,
.enter_freeze = intel_idle_freeze, },
{
.name = "C3",
.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",
.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",
.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",
.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",
.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",
.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",
.desc = "MWAIT 0x00",
.flags = MWAIT2flg(0x00),
.exit_latency = 2,
.target_residency = 2,
.enter = &intel_idle,
.enter_freeze = intel_idle_freeze, },
{
.name = "C1E",
.desc = "MWAIT 0x01",
.flags = MWAIT2flg(0x01),
.exit_latency = 10,
.target_residency = 20,
.enter = &intel_idle,
.enter_freeze = intel_idle_freeze, },
{
.name = "C6",
.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",
.desc = "MWAIT 0x00",
.flags = MWAIT2flg(0x00),
.exit_latency = 10,
.target_residency = 20,
.enter = &intel_idle,
.enter_freeze = intel_idle_freeze, },
{
.name = "C2",
.desc = "MWAIT 0x10",
.flags = MWAIT2flg(0x10),
.exit_latency = 20,
.target_residency = 80,
.enter = &intel_idle,
.enter_freeze = intel_idle_freeze, },
{
.name = "C4",
.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",
.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",
.desc = "MWAIT 0x00",
.flags = MWAIT2flg(0x00),
.exit_latency = 1,
.target_residency = 4,
.enter = &intel_idle,
.enter_freeze = intel_idle_freeze, },
{
.name = "C4",
.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",
.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",
.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",
.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",
.desc = "MWAIT 0x00",
.flags = MWAIT2flg(0x00),
.exit_latency = 2,
.target_residency = 2,
.enter = &intel_idle,
.enter_freeze = intel_idle_freeze, },
{
.name = "C6",
.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",
.desc = "MWAIT 0x00",
.flags = MWAIT2flg(0x00),
.exit_latency = 1,
.target_residency = 2,
.enter = &intel_idle,
.enter_freeze = intel_idle_freeze },
{
.name = "C6",
.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",
.desc = "MWAIT 0x00",
.flags = MWAIT2flg(0x00),
.exit_latency = 2,
.target_residency = 2,
.enter = &intel_idle,
.enter_freeze = intel_idle_freeze, },
{
.name = "C1E",
.desc = "MWAIT 0x01",
.flags = MWAIT2flg(0x01),
.exit_latency = 10,
.target_residency = 20,
.enter = &intel_idle,
.enter_freeze = intel_idle_freeze, },
{
.name = "C6",
.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",
.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",
.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",
.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",
.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",
.desc = "MWAIT 0x00",
.flags = MWAIT2flg(0x00),
.exit_latency = 2,
.target_residency = 2,
.enter = &intel_idle,
.enter_freeze = intel_idle_freeze, },
{
.name = "C1E",
.desc = "MWAIT 0x01",
.flags = MWAIT2flg(0x01),
.exit_latency = 10,
.target_residency = 20,
.enter = &intel_idle,
.enter_freeze = intel_idle_freeze, },
{
.name = "C6",
.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(bool on)
{
if (on)
tick_broadcast_enable();
else
tick_broadcast_disable();
}
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_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_GEMINI_LAKE, 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_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].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:
case INTEL_FAM6_ATOM_GEMINI_LAKE:
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(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(PREFIX "cpuidle_register_device %d failed!\n", cpu);
return -EIO;
}
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)
__setup_broadcast_timer(true);
/*
* 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;
}
static int __init intel_idle_init(void)
{
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;
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");
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(PREFIX "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);
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