linux/drivers/acpi/processor_idle.c
Borislav Petkov 07c94a3812 x86/amd: Simplify AMD E400 aware idle routine
Reorganize the E400 detection now that we have everything in place:
switch the CPUs to broadcast mode after the LAPIC has been initialized
and remove the facilities that were used previously on the idle path.

Unfortunately static_cpu_has_bug() cannpt be used in the E400 idle routine
because alternatives have been applied when the actual detection happens,
so the static switching does not take effect and the test will stay
false. Use boot_cpu_has_bug() instead which is definitely an improvement
over the RDMSR and the cpumask handling.

Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/20161209182912.2726-5-bp@alien8.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-12-09 21:23:21 +01:00

1485 lines
38 KiB
C

/*
* processor_idle - idle state submodule to the ACPI processor driver
*
* Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
* Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
* Copyright (C) 2004, 2005 Dominik Brodowski <linux@brodo.de>
* Copyright (C) 2004 Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
* - Added processor hotplug support
* Copyright (C) 2005 Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
* - Added support for C3 on SMP
*
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or (at
* your option) any later version.
*
* This program is distributed in the hope that 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.
*
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*/
#define pr_fmt(fmt) "ACPI: " fmt
#include <linux/module.h>
#include <linux/acpi.h>
#include <linux/dmi.h>
#include <linux/sched.h> /* need_resched() */
#include <linux/tick.h>
#include <linux/cpuidle.h>
#include <linux/cpu.h>
#include <acpi/processor.h>
/*
* Include the apic definitions for x86 to have the APIC timer related defines
* available also for UP (on SMP it gets magically included via linux/smp.h).
* asm/acpi.h is not an option, as it would require more include magic. Also
* creating an empty asm-ia64/apic.h would just trade pest vs. cholera.
*/
#ifdef CONFIG_X86
#include <asm/apic.h>
#endif
#define ACPI_PROCESSOR_CLASS "processor"
#define _COMPONENT ACPI_PROCESSOR_COMPONENT
ACPI_MODULE_NAME("processor_idle");
static unsigned int max_cstate __read_mostly = ACPI_PROCESSOR_MAX_POWER;
module_param(max_cstate, uint, 0000);
static unsigned int nocst __read_mostly;
module_param(nocst, uint, 0000);
static int bm_check_disable __read_mostly;
module_param(bm_check_disable, uint, 0000);
static unsigned int latency_factor __read_mostly = 2;
module_param(latency_factor, uint, 0644);
static DEFINE_PER_CPU(struct cpuidle_device *, acpi_cpuidle_device);
struct cpuidle_driver acpi_idle_driver = {
.name = "acpi_idle",
.owner = THIS_MODULE,
};
#ifdef CONFIG_ACPI_PROCESSOR_CSTATE
static
DEFINE_PER_CPU(struct acpi_processor_cx * [CPUIDLE_STATE_MAX], acpi_cstate);
static int disabled_by_idle_boot_param(void)
{
return boot_option_idle_override == IDLE_POLL ||
boot_option_idle_override == IDLE_HALT;
}
/*
* IBM ThinkPad R40e crashes mysteriously when going into C2 or C3.
* For now disable this. Probably a bug somewhere else.
*
* To skip this limit, boot/load with a large max_cstate limit.
*/
static int set_max_cstate(const struct dmi_system_id *id)
{
if (max_cstate > ACPI_PROCESSOR_MAX_POWER)
return 0;
pr_notice("%s detected - limiting to C%ld max_cstate."
" Override with \"processor.max_cstate=%d\"\n", id->ident,
(long)id->driver_data, ACPI_PROCESSOR_MAX_POWER + 1);
max_cstate = (long)id->driver_data;
return 0;
}
static const struct dmi_system_id processor_power_dmi_table[] = {
{ set_max_cstate, "Clevo 5600D", {
DMI_MATCH(DMI_BIOS_VENDOR,"Phoenix Technologies LTD"),
DMI_MATCH(DMI_BIOS_VERSION,"SHE845M0.86C.0013.D.0302131307")},
(void *)2},
{ set_max_cstate, "Pavilion zv5000", {
DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
DMI_MATCH(DMI_PRODUCT_NAME,"Pavilion zv5000 (DS502A#ABA)")},
(void *)1},
{ set_max_cstate, "Asus L8400B", {
DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
DMI_MATCH(DMI_PRODUCT_NAME,"L8400B series Notebook PC")},
(void *)1},
{},
};
/*
* Callers should disable interrupts before the call and enable
* interrupts after return.
*/
static void __cpuidle acpi_safe_halt(void)
{
if (!tif_need_resched()) {
safe_halt();
local_irq_disable();
}
}
#ifdef ARCH_APICTIMER_STOPS_ON_C3
/*
* Some BIOS implementations switch to C3 in the published C2 state.
* This seems to be a common problem on AMD boxen, but other vendors
* are affected too. We pick the most conservative approach: we assume
* that the local APIC stops in both C2 and C3.
*/
static void lapic_timer_check_state(int state, struct acpi_processor *pr,
struct acpi_processor_cx *cx)
{
struct acpi_processor_power *pwr = &pr->power;
u8 type = local_apic_timer_c2_ok ? ACPI_STATE_C3 : ACPI_STATE_C2;
if (cpu_has(&cpu_data(pr->id), X86_FEATURE_ARAT))
return;
if (boot_cpu_has_bug(X86_BUG_AMD_APIC_C1E))
type = ACPI_STATE_C1;
/*
* Check, if one of the previous states already marked the lapic
* unstable
*/
if (pwr->timer_broadcast_on_state < state)
return;
if (cx->type >= type)
pr->power.timer_broadcast_on_state = state;
}
static void __lapic_timer_propagate_broadcast(void *arg)
{
struct acpi_processor *pr = (struct acpi_processor *) arg;
if (pr->power.timer_broadcast_on_state < INT_MAX)
tick_broadcast_enable();
else
tick_broadcast_disable();
}
static void lapic_timer_propagate_broadcast(struct acpi_processor *pr)
{
smp_call_function_single(pr->id, __lapic_timer_propagate_broadcast,
(void *)pr, 1);
}
/* Power(C) State timer broadcast control */
static void lapic_timer_state_broadcast(struct acpi_processor *pr,
struct acpi_processor_cx *cx,
int broadcast)
{
int state = cx - pr->power.states;
if (state >= pr->power.timer_broadcast_on_state) {
if (broadcast)
tick_broadcast_enter();
else
tick_broadcast_exit();
}
}
#else
static void lapic_timer_check_state(int state, struct acpi_processor *pr,
struct acpi_processor_cx *cstate) { }
static void lapic_timer_propagate_broadcast(struct acpi_processor *pr) { }
static void lapic_timer_state_broadcast(struct acpi_processor *pr,
struct acpi_processor_cx *cx,
int broadcast)
{
}
#endif
#if defined(CONFIG_X86)
static void tsc_check_state(int state)
{
switch (boot_cpu_data.x86_vendor) {
case X86_VENDOR_AMD:
case X86_VENDOR_INTEL:
/*
* AMD Fam10h TSC will tick in all
* C/P/S0/S1 states when this bit is set.
*/
if (boot_cpu_has(X86_FEATURE_NONSTOP_TSC))
return;
/*FALL THROUGH*/
default:
/* TSC could halt in idle, so notify users */
if (state > ACPI_STATE_C1)
mark_tsc_unstable("TSC halts in idle");
}
}
#else
static void tsc_check_state(int state) { return; }
#endif
static int acpi_processor_get_power_info_fadt(struct acpi_processor *pr)
{
if (!pr->pblk)
return -ENODEV;
/* if info is obtained from pblk/fadt, type equals state */
pr->power.states[ACPI_STATE_C2].type = ACPI_STATE_C2;
pr->power.states[ACPI_STATE_C3].type = ACPI_STATE_C3;
#ifndef CONFIG_HOTPLUG_CPU
/*
* Check for P_LVL2_UP flag before entering C2 and above on
* an SMP system.
*/
if ((num_online_cpus() > 1) &&
!(acpi_gbl_FADT.flags & ACPI_FADT_C2_MP_SUPPORTED))
return -ENODEV;
#endif
/* determine C2 and C3 address from pblk */
pr->power.states[ACPI_STATE_C2].address = pr->pblk + 4;
pr->power.states[ACPI_STATE_C3].address = pr->pblk + 5;
/* determine latencies from FADT */
pr->power.states[ACPI_STATE_C2].latency = acpi_gbl_FADT.c2_latency;
pr->power.states[ACPI_STATE_C3].latency = acpi_gbl_FADT.c3_latency;
/*
* FADT specified C2 latency must be less than or equal to
* 100 microseconds.
*/
if (acpi_gbl_FADT.c2_latency > ACPI_PROCESSOR_MAX_C2_LATENCY) {
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
"C2 latency too large [%d]\n", acpi_gbl_FADT.c2_latency));
/* invalidate C2 */
pr->power.states[ACPI_STATE_C2].address = 0;
}
/*
* FADT supplied C3 latency must be less than or equal to
* 1000 microseconds.
*/
if (acpi_gbl_FADT.c3_latency > ACPI_PROCESSOR_MAX_C3_LATENCY) {
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
"C3 latency too large [%d]\n", acpi_gbl_FADT.c3_latency));
/* invalidate C3 */
pr->power.states[ACPI_STATE_C3].address = 0;
}
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
"lvl2[0x%08x] lvl3[0x%08x]\n",
pr->power.states[ACPI_STATE_C2].address,
pr->power.states[ACPI_STATE_C3].address));
return 0;
}
static int acpi_processor_get_power_info_default(struct acpi_processor *pr)
{
if (!pr->power.states[ACPI_STATE_C1].valid) {
/* set the first C-State to C1 */
/* all processors need to support C1 */
pr->power.states[ACPI_STATE_C1].type = ACPI_STATE_C1;
pr->power.states[ACPI_STATE_C1].valid = 1;
pr->power.states[ACPI_STATE_C1].entry_method = ACPI_CSTATE_HALT;
}
/* the C0 state only exists as a filler in our array */
pr->power.states[ACPI_STATE_C0].valid = 1;
return 0;
}
static int acpi_processor_get_power_info_cst(struct acpi_processor *pr)
{
acpi_status status;
u64 count;
int current_count;
int i, ret = 0;
struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
union acpi_object *cst;
if (nocst)
return -ENODEV;
current_count = 0;
status = acpi_evaluate_object(pr->handle, "_CST", NULL, &buffer);
if (ACPI_FAILURE(status)) {
ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No _CST, giving up\n"));
return -ENODEV;
}
cst = buffer.pointer;
/* There must be at least 2 elements */
if (!cst || (cst->type != ACPI_TYPE_PACKAGE) || cst->package.count < 2) {
pr_err("not enough elements in _CST\n");
ret = -EFAULT;
goto end;
}
count = cst->package.elements[0].integer.value;
/* Validate number of power states. */
if (count < 1 || count != cst->package.count - 1) {
pr_err("count given by _CST is not valid\n");
ret = -EFAULT;
goto end;
}
/* Tell driver that at least _CST is supported. */
pr->flags.has_cst = 1;
for (i = 1; i <= count; i++) {
union acpi_object *element;
union acpi_object *obj;
struct acpi_power_register *reg;
struct acpi_processor_cx cx;
memset(&cx, 0, sizeof(cx));
element = &(cst->package.elements[i]);
if (element->type != ACPI_TYPE_PACKAGE)
continue;
if (element->package.count != 4)
continue;
obj = &(element->package.elements[0]);
if (obj->type != ACPI_TYPE_BUFFER)
continue;
reg = (struct acpi_power_register *)obj->buffer.pointer;
if (reg->space_id != ACPI_ADR_SPACE_SYSTEM_IO &&
(reg->space_id != ACPI_ADR_SPACE_FIXED_HARDWARE))
continue;
/* There should be an easy way to extract an integer... */
obj = &(element->package.elements[1]);
if (obj->type != ACPI_TYPE_INTEGER)
continue;
cx.type = obj->integer.value;
/*
* Some buggy BIOSes won't list C1 in _CST -
* Let acpi_processor_get_power_info_default() handle them later
*/
if (i == 1 && cx.type != ACPI_STATE_C1)
current_count++;
cx.address = reg->address;
cx.index = current_count + 1;
cx.entry_method = ACPI_CSTATE_SYSTEMIO;
if (reg->space_id == ACPI_ADR_SPACE_FIXED_HARDWARE) {
if (acpi_processor_ffh_cstate_probe
(pr->id, &cx, reg) == 0) {
cx.entry_method = ACPI_CSTATE_FFH;
} else if (cx.type == ACPI_STATE_C1) {
/*
* C1 is a special case where FIXED_HARDWARE
* can be handled in non-MWAIT way as well.
* In that case, save this _CST entry info.
* Otherwise, ignore this info and continue.
*/
cx.entry_method = ACPI_CSTATE_HALT;
snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI HLT");
} else {
continue;
}
if (cx.type == ACPI_STATE_C1 &&
(boot_option_idle_override == IDLE_NOMWAIT)) {
/*
* In most cases the C1 space_id obtained from
* _CST object is FIXED_HARDWARE access mode.
* But when the option of idle=halt is added,
* the entry_method type should be changed from
* CSTATE_FFH to CSTATE_HALT.
* When the option of idle=nomwait is added,
* the C1 entry_method type should be
* CSTATE_HALT.
*/
cx.entry_method = ACPI_CSTATE_HALT;
snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI HLT");
}
} else {
snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI IOPORT 0x%x",
cx.address);
}
if (cx.type == ACPI_STATE_C1) {
cx.valid = 1;
}
obj = &(element->package.elements[2]);
if (obj->type != ACPI_TYPE_INTEGER)
continue;
cx.latency = obj->integer.value;
obj = &(element->package.elements[3]);
if (obj->type != ACPI_TYPE_INTEGER)
continue;
current_count++;
memcpy(&(pr->power.states[current_count]), &cx, sizeof(cx));
/*
* We support total ACPI_PROCESSOR_MAX_POWER - 1
* (From 1 through ACPI_PROCESSOR_MAX_POWER - 1)
*/
if (current_count >= (ACPI_PROCESSOR_MAX_POWER - 1)) {
pr_warn("Limiting number of power states to max (%d)\n",
ACPI_PROCESSOR_MAX_POWER);
pr_warn("Please increase ACPI_PROCESSOR_MAX_POWER if needed.\n");
break;
}
}
ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d power states\n",
current_count));
/* Validate number of power states discovered */
if (current_count < 2)
ret = -EFAULT;
end:
kfree(buffer.pointer);
return ret;
}
static void acpi_processor_power_verify_c3(struct acpi_processor *pr,
struct acpi_processor_cx *cx)
{
static int bm_check_flag = -1;
static int bm_control_flag = -1;
if (!cx->address)
return;
/*
* PIIX4 Erratum #18: We don't support C3 when Type-F (fast)
* DMA transfers are used by any ISA device to avoid livelock.
* Note that we could disable Type-F DMA (as recommended by
* the erratum), but this is known to disrupt certain ISA
* devices thus we take the conservative approach.
*/
else if (errata.piix4.fdma) {
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
"C3 not supported on PIIX4 with Type-F DMA\n"));
return;
}
/* All the logic here assumes flags.bm_check is same across all CPUs */
if (bm_check_flag == -1) {
/* Determine whether bm_check is needed based on CPU */
acpi_processor_power_init_bm_check(&(pr->flags), pr->id);
bm_check_flag = pr->flags.bm_check;
bm_control_flag = pr->flags.bm_control;
} else {
pr->flags.bm_check = bm_check_flag;
pr->flags.bm_control = bm_control_flag;
}
if (pr->flags.bm_check) {
if (!pr->flags.bm_control) {
if (pr->flags.has_cst != 1) {
/* bus mastering control is necessary */
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
"C3 support requires BM control\n"));
return;
} else {
/* Here we enter C3 without bus mastering */
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
"C3 support without BM control\n"));
}
}
} else {
/*
* WBINVD should be set in fadt, for C3 state to be
* supported on when bm_check is not required.
*/
if (!(acpi_gbl_FADT.flags & ACPI_FADT_WBINVD)) {
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
"Cache invalidation should work properly"
" for C3 to be enabled on SMP systems\n"));
return;
}
}
/*
* Otherwise we've met all of our C3 requirements.
* Normalize the C3 latency to expidite policy. Enable
* checking of bus mastering status (bm_check) so we can
* use this in our C3 policy
*/
cx->valid = 1;
/*
* On older chipsets, BM_RLD needs to be set
* in order for Bus Master activity to wake the
* system from C3. Newer chipsets handle DMA
* during C3 automatically and BM_RLD is a NOP.
* In either case, the proper way to
* handle BM_RLD is to set it and leave it set.
*/
acpi_write_bit_register(ACPI_BITREG_BUS_MASTER_RLD, 1);
return;
}
static int acpi_processor_power_verify(struct acpi_processor *pr)
{
unsigned int i;
unsigned int working = 0;
pr->power.timer_broadcast_on_state = INT_MAX;
for (i = 1; i < ACPI_PROCESSOR_MAX_POWER && i <= max_cstate; i++) {
struct acpi_processor_cx *cx = &pr->power.states[i];
switch (cx->type) {
case ACPI_STATE_C1:
cx->valid = 1;
break;
case ACPI_STATE_C2:
if (!cx->address)
break;
cx->valid = 1;
break;
case ACPI_STATE_C3:
acpi_processor_power_verify_c3(pr, cx);
break;
}
if (!cx->valid)
continue;
lapic_timer_check_state(i, pr, cx);
tsc_check_state(cx->type);
working++;
}
lapic_timer_propagate_broadcast(pr);
return (working);
}
static int acpi_processor_get_cstate_info(struct acpi_processor *pr)
{
unsigned int i;
int result;
/* NOTE: the idle thread may not be running while calling
* this function */
/* Zero initialize all the C-states info. */
memset(pr->power.states, 0, sizeof(pr->power.states));
result = acpi_processor_get_power_info_cst(pr);
if (result == -ENODEV)
result = acpi_processor_get_power_info_fadt(pr);
if (result)
return result;
acpi_processor_get_power_info_default(pr);
pr->power.count = acpi_processor_power_verify(pr);
/*
* if one state of type C2 or C3 is available, mark this
* CPU as being "idle manageable"
*/
for (i = 1; i < ACPI_PROCESSOR_MAX_POWER; i++) {
if (pr->power.states[i].valid) {
pr->power.count = i;
if (pr->power.states[i].type >= ACPI_STATE_C2)
pr->flags.power = 1;
}
}
return 0;
}
/**
* acpi_idle_bm_check - checks if bus master activity was detected
*/
static int acpi_idle_bm_check(void)
{
u32 bm_status = 0;
if (bm_check_disable)
return 0;
acpi_read_bit_register(ACPI_BITREG_BUS_MASTER_STATUS, &bm_status);
if (bm_status)
acpi_write_bit_register(ACPI_BITREG_BUS_MASTER_STATUS, 1);
/*
* PIIX4 Erratum #18: Note that BM_STS doesn't always reflect
* the true state of bus mastering activity; forcing us to
* manually check the BMIDEA bit of each IDE channel.
*/
else if (errata.piix4.bmisx) {
if ((inb_p(errata.piix4.bmisx + 0x02) & 0x01)
|| (inb_p(errata.piix4.bmisx + 0x0A) & 0x01))
bm_status = 1;
}
return bm_status;
}
/**
* acpi_idle_do_entry - enter idle state using the appropriate method
* @cx: cstate data
*
* Caller disables interrupt before call and enables interrupt after return.
*/
static void __cpuidle acpi_idle_do_entry(struct acpi_processor_cx *cx)
{
if (cx->entry_method == ACPI_CSTATE_FFH) {
/* Call into architectural FFH based C-state */
acpi_processor_ffh_cstate_enter(cx);
} else if (cx->entry_method == ACPI_CSTATE_HALT) {
acpi_safe_halt();
} else {
/* IO port based C-state */
inb(cx->address);
/* Dummy wait op - must do something useless after P_LVL2 read
because chipsets cannot guarantee that STPCLK# signal
gets asserted in time to freeze execution properly. */
inl(acpi_gbl_FADT.xpm_timer_block.address);
}
}
/**
* acpi_idle_play_dead - enters an ACPI state for long-term idle (i.e. off-lining)
* @dev: the target CPU
* @index: the index of suggested state
*/
static int acpi_idle_play_dead(struct cpuidle_device *dev, int index)
{
struct acpi_processor_cx *cx = per_cpu(acpi_cstate[index], dev->cpu);
ACPI_FLUSH_CPU_CACHE();
while (1) {
if (cx->entry_method == ACPI_CSTATE_HALT)
safe_halt();
else if (cx->entry_method == ACPI_CSTATE_SYSTEMIO) {
inb(cx->address);
/* See comment in acpi_idle_do_entry() */
inl(acpi_gbl_FADT.xpm_timer_block.address);
} else
return -ENODEV;
}
/* Never reached */
return 0;
}
static bool acpi_idle_fallback_to_c1(struct acpi_processor *pr)
{
return IS_ENABLED(CONFIG_HOTPLUG_CPU) && !pr->flags.has_cst &&
!(acpi_gbl_FADT.flags & ACPI_FADT_C2_MP_SUPPORTED);
}
static int c3_cpu_count;
static DEFINE_RAW_SPINLOCK(c3_lock);
/**
* acpi_idle_enter_bm - enters C3 with proper BM handling
* @pr: Target processor
* @cx: Target state context
* @timer_bc: Whether or not to change timer mode to broadcast
*/
static void acpi_idle_enter_bm(struct acpi_processor *pr,
struct acpi_processor_cx *cx, bool timer_bc)
{
acpi_unlazy_tlb(smp_processor_id());
/*
* Must be done before busmaster disable as we might need to
* access HPET !
*/
if (timer_bc)
lapic_timer_state_broadcast(pr, cx, 1);
/*
* disable bus master
* bm_check implies we need ARB_DIS
* bm_control implies whether we can do ARB_DIS
*
* That leaves a case where bm_check is set and bm_control is
* not set. In that case we cannot do much, we enter C3
* without doing anything.
*/
if (pr->flags.bm_control) {
raw_spin_lock(&c3_lock);
c3_cpu_count++;
/* Disable bus master arbitration when all CPUs are in C3 */
if (c3_cpu_count == num_online_cpus())
acpi_write_bit_register(ACPI_BITREG_ARB_DISABLE, 1);
raw_spin_unlock(&c3_lock);
}
acpi_idle_do_entry(cx);
/* Re-enable bus master arbitration */
if (pr->flags.bm_control) {
raw_spin_lock(&c3_lock);
acpi_write_bit_register(ACPI_BITREG_ARB_DISABLE, 0);
c3_cpu_count--;
raw_spin_unlock(&c3_lock);
}
if (timer_bc)
lapic_timer_state_broadcast(pr, cx, 0);
}
static int acpi_idle_enter(struct cpuidle_device *dev,
struct cpuidle_driver *drv, int index)
{
struct acpi_processor_cx *cx = per_cpu(acpi_cstate[index], dev->cpu);
struct acpi_processor *pr;
pr = __this_cpu_read(processors);
if (unlikely(!pr))
return -EINVAL;
if (cx->type != ACPI_STATE_C1) {
if (acpi_idle_fallback_to_c1(pr) && num_online_cpus() > 1) {
index = CPUIDLE_DRIVER_STATE_START;
cx = per_cpu(acpi_cstate[index], dev->cpu);
} else if (cx->type == ACPI_STATE_C3 && pr->flags.bm_check) {
if (cx->bm_sts_skip || !acpi_idle_bm_check()) {
acpi_idle_enter_bm(pr, cx, true);
return index;
} else if (drv->safe_state_index >= 0) {
index = drv->safe_state_index;
cx = per_cpu(acpi_cstate[index], dev->cpu);
} else {
acpi_safe_halt();
return -EBUSY;
}
}
}
lapic_timer_state_broadcast(pr, cx, 1);
if (cx->type == ACPI_STATE_C3)
ACPI_FLUSH_CPU_CACHE();
acpi_idle_do_entry(cx);
lapic_timer_state_broadcast(pr, cx, 0);
return index;
}
static void acpi_idle_enter_freeze(struct cpuidle_device *dev,
struct cpuidle_driver *drv, int index)
{
struct acpi_processor_cx *cx = per_cpu(acpi_cstate[index], dev->cpu);
if (cx->type == ACPI_STATE_C3) {
struct acpi_processor *pr = __this_cpu_read(processors);
if (unlikely(!pr))
return;
if (pr->flags.bm_check) {
acpi_idle_enter_bm(pr, cx, false);
return;
} else {
ACPI_FLUSH_CPU_CACHE();
}
}
acpi_idle_do_entry(cx);
}
static int acpi_processor_setup_cpuidle_cx(struct acpi_processor *pr,
struct cpuidle_device *dev)
{
int i, count = CPUIDLE_DRIVER_STATE_START;
struct acpi_processor_cx *cx;
if (max_cstate == 0)
max_cstate = 1;
for (i = 1; i < ACPI_PROCESSOR_MAX_POWER && i <= max_cstate; i++) {
cx = &pr->power.states[i];
if (!cx->valid)
continue;
per_cpu(acpi_cstate[count], dev->cpu) = cx;
count++;
if (count == CPUIDLE_STATE_MAX)
break;
}
if (!count)
return -EINVAL;
return 0;
}
static int acpi_processor_setup_cstates(struct acpi_processor *pr)
{
int i, count = CPUIDLE_DRIVER_STATE_START;
struct acpi_processor_cx *cx;
struct cpuidle_state *state;
struct cpuidle_driver *drv = &acpi_idle_driver;
if (max_cstate == 0)
max_cstate = 1;
for (i = 1; i < ACPI_PROCESSOR_MAX_POWER && i <= max_cstate; i++) {
cx = &pr->power.states[i];
if (!cx->valid)
continue;
state = &drv->states[count];
snprintf(state->name, CPUIDLE_NAME_LEN, "C%d", i);
strlcpy(state->desc, cx->desc, CPUIDLE_DESC_LEN);
state->exit_latency = cx->latency;
state->target_residency = cx->latency * latency_factor;
state->enter = acpi_idle_enter;
state->flags = 0;
if (cx->type == ACPI_STATE_C1 || cx->type == ACPI_STATE_C2) {
state->enter_dead = acpi_idle_play_dead;
drv->safe_state_index = count;
}
/*
* Halt-induced C1 is not good for ->enter_freeze, because it
* re-enables interrupts on exit. Moreover, C1 is generally not
* particularly interesting from the suspend-to-idle angle, so
* avoid C1 and the situations in which we may need to fall back
* to it altogether.
*/
if (cx->type != ACPI_STATE_C1 && !acpi_idle_fallback_to_c1(pr))
state->enter_freeze = acpi_idle_enter_freeze;
count++;
if (count == CPUIDLE_STATE_MAX)
break;
}
drv->state_count = count;
if (!count)
return -EINVAL;
return 0;
}
static inline void acpi_processor_cstate_first_run_checks(void)
{
acpi_status status;
static int first_run;
if (first_run)
return;
dmi_check_system(processor_power_dmi_table);
max_cstate = acpi_processor_cstate_check(max_cstate);
if (max_cstate < ACPI_C_STATES_MAX)
pr_notice("ACPI: processor limited to max C-state %d\n",
max_cstate);
first_run++;
if (acpi_gbl_FADT.cst_control && !nocst) {
status = acpi_os_write_port(acpi_gbl_FADT.smi_command,
acpi_gbl_FADT.cst_control, 8);
if (ACPI_FAILURE(status))
ACPI_EXCEPTION((AE_INFO, status,
"Notifying BIOS of _CST ability failed"));
}
}
#else
static inline int disabled_by_idle_boot_param(void) { return 0; }
static inline void acpi_processor_cstate_first_run_checks(void) { }
static int acpi_processor_get_cstate_info(struct acpi_processor *pr)
{
return -ENODEV;
}
static int acpi_processor_setup_cpuidle_cx(struct acpi_processor *pr,
struct cpuidle_device *dev)
{
return -EINVAL;
}
static int acpi_processor_setup_cstates(struct acpi_processor *pr)
{
return -EINVAL;
}
#endif /* CONFIG_ACPI_PROCESSOR_CSTATE */
struct acpi_lpi_states_array {
unsigned int size;
unsigned int composite_states_size;
struct acpi_lpi_state *entries;
struct acpi_lpi_state *composite_states[ACPI_PROCESSOR_MAX_POWER];
};
static int obj_get_integer(union acpi_object *obj, u32 *value)
{
if (obj->type != ACPI_TYPE_INTEGER)
return -EINVAL;
*value = obj->integer.value;
return 0;
}
static int acpi_processor_evaluate_lpi(acpi_handle handle,
struct acpi_lpi_states_array *info)
{
acpi_status status;
int ret = 0;
int pkg_count, state_idx = 1, loop;
struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
union acpi_object *lpi_data;
struct acpi_lpi_state *lpi_state;
status = acpi_evaluate_object(handle, "_LPI", NULL, &buffer);
if (ACPI_FAILURE(status)) {
ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No _LPI, giving up\n"));
return -ENODEV;
}
lpi_data = buffer.pointer;
/* There must be at least 4 elements = 3 elements + 1 package */
if (!lpi_data || lpi_data->type != ACPI_TYPE_PACKAGE ||
lpi_data->package.count < 4) {
pr_debug("not enough elements in _LPI\n");
ret = -ENODATA;
goto end;
}
pkg_count = lpi_data->package.elements[2].integer.value;
/* Validate number of power states. */
if (pkg_count < 1 || pkg_count != lpi_data->package.count - 3) {
pr_debug("count given by _LPI is not valid\n");
ret = -ENODATA;
goto end;
}
lpi_state = kcalloc(pkg_count, sizeof(*lpi_state), GFP_KERNEL);
if (!lpi_state) {
ret = -ENOMEM;
goto end;
}
info->size = pkg_count;
info->entries = lpi_state;
/* LPI States start at index 3 */
for (loop = 3; state_idx <= pkg_count; loop++, state_idx++, lpi_state++) {
union acpi_object *element, *pkg_elem, *obj;
element = &lpi_data->package.elements[loop];
if (element->type != ACPI_TYPE_PACKAGE || element->package.count < 7)
continue;
pkg_elem = element->package.elements;
obj = pkg_elem + 6;
if (obj->type == ACPI_TYPE_BUFFER) {
struct acpi_power_register *reg;
reg = (struct acpi_power_register *)obj->buffer.pointer;
if (reg->space_id != ACPI_ADR_SPACE_SYSTEM_IO &&
reg->space_id != ACPI_ADR_SPACE_FIXED_HARDWARE)
continue;
lpi_state->address = reg->address;
lpi_state->entry_method =
reg->space_id == ACPI_ADR_SPACE_FIXED_HARDWARE ?
ACPI_CSTATE_FFH : ACPI_CSTATE_SYSTEMIO;
} else if (obj->type == ACPI_TYPE_INTEGER) {
lpi_state->entry_method = ACPI_CSTATE_INTEGER;
lpi_state->address = obj->integer.value;
} else {
continue;
}
/* elements[7,8] skipped for now i.e. Residency/Usage counter*/
obj = pkg_elem + 9;
if (obj->type == ACPI_TYPE_STRING)
strlcpy(lpi_state->desc, obj->string.pointer,
ACPI_CX_DESC_LEN);
lpi_state->index = state_idx;
if (obj_get_integer(pkg_elem + 0, &lpi_state->min_residency)) {
pr_debug("No min. residency found, assuming 10 us\n");
lpi_state->min_residency = 10;
}
if (obj_get_integer(pkg_elem + 1, &lpi_state->wake_latency)) {
pr_debug("No wakeup residency found, assuming 10 us\n");
lpi_state->wake_latency = 10;
}
if (obj_get_integer(pkg_elem + 2, &lpi_state->flags))
lpi_state->flags = 0;
if (obj_get_integer(pkg_elem + 3, &lpi_state->arch_flags))
lpi_state->arch_flags = 0;
if (obj_get_integer(pkg_elem + 4, &lpi_state->res_cnt_freq))
lpi_state->res_cnt_freq = 1;
if (obj_get_integer(pkg_elem + 5, &lpi_state->enable_parent_state))
lpi_state->enable_parent_state = 0;
}
acpi_handle_debug(handle, "Found %d power states\n", state_idx);
end:
kfree(buffer.pointer);
return ret;
}
/*
* flat_state_cnt - the number of composite LPI states after the process of flattening
*/
static int flat_state_cnt;
/**
* combine_lpi_states - combine local and parent LPI states to form a composite LPI state
*
* @local: local LPI state
* @parent: parent LPI state
* @result: composite LPI state
*/
static bool combine_lpi_states(struct acpi_lpi_state *local,
struct acpi_lpi_state *parent,
struct acpi_lpi_state *result)
{
if (parent->entry_method == ACPI_CSTATE_INTEGER) {
if (!parent->address) /* 0 means autopromotable */
return false;
result->address = local->address + parent->address;
} else {
result->address = parent->address;
}
result->min_residency = max(local->min_residency, parent->min_residency);
result->wake_latency = local->wake_latency + parent->wake_latency;
result->enable_parent_state = parent->enable_parent_state;
result->entry_method = local->entry_method;
result->flags = parent->flags;
result->arch_flags = parent->arch_flags;
result->index = parent->index;
strlcpy(result->desc, local->desc, ACPI_CX_DESC_LEN);
strlcat(result->desc, "+", ACPI_CX_DESC_LEN);
strlcat(result->desc, parent->desc, ACPI_CX_DESC_LEN);
return true;
}
#define ACPI_LPI_STATE_FLAGS_ENABLED BIT(0)
static void stash_composite_state(struct acpi_lpi_states_array *curr_level,
struct acpi_lpi_state *t)
{
curr_level->composite_states[curr_level->composite_states_size++] = t;
}
static int flatten_lpi_states(struct acpi_processor *pr,
struct acpi_lpi_states_array *curr_level,
struct acpi_lpi_states_array *prev_level)
{
int i, j, state_count = curr_level->size;
struct acpi_lpi_state *p, *t = curr_level->entries;
curr_level->composite_states_size = 0;
for (j = 0; j < state_count; j++, t++) {
struct acpi_lpi_state *flpi;
if (!(t->flags & ACPI_LPI_STATE_FLAGS_ENABLED))
continue;
if (flat_state_cnt >= ACPI_PROCESSOR_MAX_POWER) {
pr_warn("Limiting number of LPI states to max (%d)\n",
ACPI_PROCESSOR_MAX_POWER);
pr_warn("Please increase ACPI_PROCESSOR_MAX_POWER if needed.\n");
break;
}
flpi = &pr->power.lpi_states[flat_state_cnt];
if (!prev_level) { /* leaf/processor node */
memcpy(flpi, t, sizeof(*t));
stash_composite_state(curr_level, flpi);
flat_state_cnt++;
continue;
}
for (i = 0; i < prev_level->composite_states_size; i++) {
p = prev_level->composite_states[i];
if (t->index <= p->enable_parent_state &&
combine_lpi_states(p, t, flpi)) {
stash_composite_state(curr_level, flpi);
flat_state_cnt++;
flpi++;
}
}
}
kfree(curr_level->entries);
return 0;
}
static int acpi_processor_get_lpi_info(struct acpi_processor *pr)
{
int ret, i;
acpi_status status;
acpi_handle handle = pr->handle, pr_ahandle;
struct acpi_device *d = NULL;
struct acpi_lpi_states_array info[2], *tmp, *prev, *curr;
if (!osc_pc_lpi_support_confirmed)
return -EOPNOTSUPP;
if (!acpi_has_method(handle, "_LPI"))
return -EINVAL;
flat_state_cnt = 0;
prev = &info[0];
curr = &info[1];
handle = pr->handle;
ret = acpi_processor_evaluate_lpi(handle, prev);
if (ret)
return ret;
flatten_lpi_states(pr, prev, NULL);
status = acpi_get_parent(handle, &pr_ahandle);
while (ACPI_SUCCESS(status)) {
acpi_bus_get_device(pr_ahandle, &d);
handle = pr_ahandle;
if (strcmp(acpi_device_hid(d), ACPI_PROCESSOR_CONTAINER_HID))
break;
/* can be optional ? */
if (!acpi_has_method(handle, "_LPI"))
break;
ret = acpi_processor_evaluate_lpi(handle, curr);
if (ret)
break;
/* flatten all the LPI states in this level of hierarchy */
flatten_lpi_states(pr, curr, prev);
tmp = prev, prev = curr, curr = tmp;
status = acpi_get_parent(handle, &pr_ahandle);
}
pr->power.count = flat_state_cnt;
/* reset the index after flattening */
for (i = 0; i < pr->power.count; i++)
pr->power.lpi_states[i].index = i;
/* Tell driver that _LPI is supported. */
pr->flags.has_lpi = 1;
pr->flags.power = 1;
return 0;
}
int __weak acpi_processor_ffh_lpi_probe(unsigned int cpu)
{
return -ENODEV;
}
int __weak acpi_processor_ffh_lpi_enter(struct acpi_lpi_state *lpi)
{
return -ENODEV;
}
/**
* acpi_idle_lpi_enter - enters an ACPI any LPI state
* @dev: the target CPU
* @drv: cpuidle driver containing cpuidle state info
* @index: index of target state
*
* Return: 0 for success or negative value for error
*/
static int acpi_idle_lpi_enter(struct cpuidle_device *dev,
struct cpuidle_driver *drv, int index)
{
struct acpi_processor *pr;
struct acpi_lpi_state *lpi;
pr = __this_cpu_read(processors);
if (unlikely(!pr))
return -EINVAL;
lpi = &pr->power.lpi_states[index];
if (lpi->entry_method == ACPI_CSTATE_FFH)
return acpi_processor_ffh_lpi_enter(lpi);
return -EINVAL;
}
static int acpi_processor_setup_lpi_states(struct acpi_processor *pr)
{
int i;
struct acpi_lpi_state *lpi;
struct cpuidle_state *state;
struct cpuidle_driver *drv = &acpi_idle_driver;
if (!pr->flags.has_lpi)
return -EOPNOTSUPP;
for (i = 0; i < pr->power.count && i < CPUIDLE_STATE_MAX; i++) {
lpi = &pr->power.lpi_states[i];
state = &drv->states[i];
snprintf(state->name, CPUIDLE_NAME_LEN, "LPI-%d", i);
strlcpy(state->desc, lpi->desc, CPUIDLE_DESC_LEN);
state->exit_latency = lpi->wake_latency;
state->target_residency = lpi->min_residency;
if (lpi->arch_flags)
state->flags |= CPUIDLE_FLAG_TIMER_STOP;
state->enter = acpi_idle_lpi_enter;
drv->safe_state_index = i;
}
drv->state_count = i;
return 0;
}
/**
* acpi_processor_setup_cpuidle_states- prepares and configures cpuidle
* global state data i.e. idle routines
*
* @pr: the ACPI processor
*/
static int acpi_processor_setup_cpuidle_states(struct acpi_processor *pr)
{
int i;
struct cpuidle_driver *drv = &acpi_idle_driver;
if (!pr->flags.power_setup_done || !pr->flags.power)
return -EINVAL;
drv->safe_state_index = -1;
for (i = CPUIDLE_DRIVER_STATE_START; i < CPUIDLE_STATE_MAX; i++) {
drv->states[i].name[0] = '\0';
drv->states[i].desc[0] = '\0';
}
if (pr->flags.has_lpi)
return acpi_processor_setup_lpi_states(pr);
return acpi_processor_setup_cstates(pr);
}
/**
* acpi_processor_setup_cpuidle_dev - prepares and configures CPUIDLE
* device i.e. per-cpu data
*
* @pr: the ACPI processor
* @dev : the cpuidle device
*/
static int acpi_processor_setup_cpuidle_dev(struct acpi_processor *pr,
struct cpuidle_device *dev)
{
if (!pr->flags.power_setup_done || !pr->flags.power || !dev)
return -EINVAL;
dev->cpu = pr->id;
if (pr->flags.has_lpi)
return acpi_processor_ffh_lpi_probe(pr->id);
return acpi_processor_setup_cpuidle_cx(pr, dev);
}
static int acpi_processor_get_power_info(struct acpi_processor *pr)
{
int ret;
ret = acpi_processor_get_lpi_info(pr);
if (ret)
ret = acpi_processor_get_cstate_info(pr);
return ret;
}
int acpi_processor_hotplug(struct acpi_processor *pr)
{
int ret = 0;
struct cpuidle_device *dev;
if (disabled_by_idle_boot_param())
return 0;
if (!pr->flags.power_setup_done)
return -ENODEV;
dev = per_cpu(acpi_cpuidle_device, pr->id);
cpuidle_pause_and_lock();
cpuidle_disable_device(dev);
ret = acpi_processor_get_power_info(pr);
if (!ret && pr->flags.power) {
acpi_processor_setup_cpuidle_dev(pr, dev);
ret = cpuidle_enable_device(dev);
}
cpuidle_resume_and_unlock();
return ret;
}
int acpi_processor_power_state_has_changed(struct acpi_processor *pr)
{
int cpu;
struct acpi_processor *_pr;
struct cpuidle_device *dev;
if (disabled_by_idle_boot_param())
return 0;
if (!pr->flags.power_setup_done)
return -ENODEV;
/*
* FIXME: Design the ACPI notification to make it once per
* system instead of once per-cpu. This condition is a hack
* to make the code that updates C-States be called once.
*/
if (pr->id == 0 && cpuidle_get_driver() == &acpi_idle_driver) {
/* Protect against cpu-hotplug */
get_online_cpus();
cpuidle_pause_and_lock();
/* Disable all cpuidle devices */
for_each_online_cpu(cpu) {
_pr = per_cpu(processors, cpu);
if (!_pr || !_pr->flags.power_setup_done)
continue;
dev = per_cpu(acpi_cpuidle_device, cpu);
cpuidle_disable_device(dev);
}
/* Populate Updated C-state information */
acpi_processor_get_power_info(pr);
acpi_processor_setup_cpuidle_states(pr);
/* Enable all cpuidle devices */
for_each_online_cpu(cpu) {
_pr = per_cpu(processors, cpu);
if (!_pr || !_pr->flags.power_setup_done)
continue;
acpi_processor_get_power_info(_pr);
if (_pr->flags.power) {
dev = per_cpu(acpi_cpuidle_device, cpu);
acpi_processor_setup_cpuidle_dev(_pr, dev);
cpuidle_enable_device(dev);
}
}
cpuidle_resume_and_unlock();
put_online_cpus();
}
return 0;
}
static int acpi_processor_registered;
int acpi_processor_power_init(struct acpi_processor *pr)
{
int retval;
struct cpuidle_device *dev;
if (disabled_by_idle_boot_param())
return 0;
acpi_processor_cstate_first_run_checks();
if (!acpi_processor_get_power_info(pr))
pr->flags.power_setup_done = 1;
/*
* Install the idle handler if processor power management is supported.
* Note that we use previously set idle handler will be used on
* platforms that only support C1.
*/
if (pr->flags.power) {
/* Register acpi_idle_driver if not already registered */
if (!acpi_processor_registered) {
acpi_processor_setup_cpuidle_states(pr);
retval = cpuidle_register_driver(&acpi_idle_driver);
if (retval)
return retval;
pr_debug("%s registered with cpuidle\n",
acpi_idle_driver.name);
}
dev = kzalloc(sizeof(*dev), GFP_KERNEL);
if (!dev)
return -ENOMEM;
per_cpu(acpi_cpuidle_device, pr->id) = dev;
acpi_processor_setup_cpuidle_dev(pr, dev);
/* Register per-cpu cpuidle_device. Cpuidle driver
* must already be registered before registering device
*/
retval = cpuidle_register_device(dev);
if (retval) {
if (acpi_processor_registered == 0)
cpuidle_unregister_driver(&acpi_idle_driver);
return retval;
}
acpi_processor_registered++;
}
return 0;
}
int acpi_processor_power_exit(struct acpi_processor *pr)
{
struct cpuidle_device *dev = per_cpu(acpi_cpuidle_device, pr->id);
if (disabled_by_idle_boot_param())
return 0;
if (pr->flags.power) {
cpuidle_unregister_device(dev);
acpi_processor_registered--;
if (acpi_processor_registered == 0)
cpuidle_unregister_driver(&acpi_idle_driver);
}
pr->flags.power_setup_done = 0;
return 0;
}