/**
* acpi_idle_enter_c1 - enters an ACPI C1 state-type
* @dev: the target CPU
* @state: the state data
*
* This is equivalent to the HALT instruction.
*/
static int acpi_idle_enter_c1(struct cpuidle_device *dev,
struct cpuidle_state *state)
{
ktime_t kt1, kt2;
s64 idle_time;
struct acpi_processor *pr;
struct acpi_processor_cx *cx = cpuidle_get_statedata(state);
pr = __get_cpu_var(processors);
if (unlikely(!pr))
return 0;
local_irq_disable();
/* Do not access any ACPI IO ports in suspend path */
if (acpi_idle_suspend) {
acpi_safe_halt();
local_irq_enable();
// cpu_relax();
return 0;
}
lapic_timer_state_broadcast(pr, cx, 1);
kt1 = ktime_get_real();
acpi_idle_do_entry(cx);
kt2 = ktime_get_real();
idle_time = ktime_to_us(ktime_sub(kt2, kt1));
local_irq_enable();
cx->usage++;
lapic_timer_state_broadcast(pr, cx, 0);
return idle_time;
}
/**
* 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);
}
}
static inline void acpi_idle_do_entry(struct acpi_processor_cx *cx)
{
stop_critical_timings();
if (cx->entry_method == ACPI_CSTATE_FFH) {
acpi_processor_ffh_cstate_enter(cx);
} else if (cx->entry_method == ACPI_CSTATE_HALT) {
acpi_safe_halt();
} else {
inb(cx->address);
inl(acpi_gbl_FADT.xpm_timer_block.address);
}
start_critical_timings();
}
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 = ACPI_IDLE_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;
}
/**
* acpi_idle_enter_bm - enters C3 with proper BM handling
* @dev: the target CPU
* @state: the state data
*
* If BM is detected, the deepest non-C3 idle state is entered instead.
*/
static int acpi_idle_enter_bm(struct cpuidle_device *dev,
struct cpuidle_state *state)
{
struct acpi_processor *pr;
struct acpi_processor_cx *cx = cpuidle_get_statedata(state);
ktime_t kt1, kt2;
s64 idle_time_ns;
s64 idle_time;
pr = __get_cpu_var(processors);
if (unlikely(!pr))
return 0;
if (acpi_idle_suspend)
return(acpi_idle_enter_c1(dev, state));
if (!cx->bm_sts_skip && acpi_idle_bm_check()) {
if (dev->safe_state) {
dev->last_state = dev->safe_state;
return dev->safe_state->enter(dev, dev->safe_state);
} else {
local_irq_disable();
acpi_safe_halt();
local_irq_enable();
return 0;
}
}
local_irq_disable();
if (cx->entry_method != ACPI_CSTATE_FFH) {
current_thread_info()->status &= ~TS_POLLING;
/*
* TS_POLLING-cleared state must be visible before we test
* NEED_RESCHED:
*/
smp_mb();
if (unlikely(need_resched())) {
current_thread_info()->status |= TS_POLLING;
local_irq_enable();
return 0;
}
}
acpi_unlazy_tlb(smp_processor_id());
/* Tell the scheduler that we are going deep-idle: */
sched_clock_idle_sleep_event();
/*
* Must be done before busmaster disable as we might need to
* access HPET !
*/
lapic_timer_state_broadcast(pr, cx, 1);
kt1 = ktime_get_real();
/*
* disable bus master
* bm_check implies we need ARB_DIS
* !bm_check implies we need cache flush
* 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_check && pr->flags.bm_control) {
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);
spin_unlock(&c3_lock);
} else if (!pr->flags.bm_check) {
ACPI_FLUSH_CPU_CACHE();
}
acpi_idle_do_entry(cx);
/* Re-enable bus master arbitration */
if (pr->flags.bm_check && pr->flags.bm_control) {
spin_lock(&c3_lock);
acpi_write_bit_register(ACPI_BITREG_ARB_DISABLE, 0);
c3_cpu_count--;
spin_unlock(&c3_lock);
}
kt2 = ktime_get_real();
idle_time_ns = ktime_to_ns(ktime_sub(kt2, kt1));
idle_time = idle_time_ns;
do_div(idle_time, NSEC_PER_USEC);
/* Tell the scheduler how much we idled: */
sched_clock_idle_wakeup_event(idle_time_ns);
local_irq_enable();
if (cx->entry_method != ACPI_CSTATE_FFH)
current_thread_info()->status |= TS_POLLING;
cx->usage++;
lapic_timer_state_broadcast(pr, cx, 0);
cx->time += idle_time;
return idle_time;
}
static int acpi_idle_enter_bm(struct cpuidle_device *dev,
struct cpuidle_driver *drv, int index)
{
struct acpi_processor *pr;
struct cpuidle_state_usage *state_usage = &dev->states_usage[index];
struct acpi_processor_cx *cx = cpuidle_get_statedata(state_usage);
ktime_t kt1, kt2;
s64 idle_time_ns;
s64 idle_time;
pr = __this_cpu_read(processors);
dev->last_residency = 0;
if (unlikely(!pr))
return -EINVAL;
if (!cx->bm_sts_skip && acpi_idle_bm_check()) {
if (drv->safe_state_index >= 0) {
return drv->states[drv->safe_state_index].enter(dev,
drv, drv->safe_state_index);
} else {
local_irq_disable();
acpi_safe_halt();
local_irq_enable();
return -EINVAL;
}
}
local_irq_disable();
if (cx->entry_method != ACPI_CSTATE_FFH) {
current_thread_info()->status &= ~TS_POLLING;
smp_mb();
if (unlikely(need_resched())) {
current_thread_info()->status |= TS_POLLING;
local_irq_enable();
return -EINVAL;
}
}
acpi_unlazy_tlb(smp_processor_id());
sched_clock_idle_sleep_event();
lapic_timer_state_broadcast(pr, cx, 1);
kt1 = ktime_get_real();
if (pr->flags.bm_check && pr->flags.bm_control) {
raw_spin_lock(&c3_lock);
c3_cpu_count++;
if (c3_cpu_count == num_online_cpus())
acpi_write_bit_register(ACPI_BITREG_ARB_DISABLE, 1);
raw_spin_unlock(&c3_lock);
} else if (!pr->flags.bm_check) {
ACPI_FLUSH_CPU_CACHE();
}
acpi_idle_do_entry(cx);
if (pr->flags.bm_check && 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);
}
kt2 = ktime_get_real();
idle_time_ns = ktime_to_ns(ktime_sub(kt2, kt1));
idle_time = idle_time_ns;
do_div(idle_time, NSEC_PER_USEC);
dev->last_residency = (int)idle_time;
sched_clock_idle_wakeup_event(idle_time_ns);
local_irq_enable();
if (cx->entry_method != ACPI_CSTATE_FFH)
current_thread_info()->status |= TS_POLLING;
cx->usage++;
lapic_timer_state_broadcast(pr, cx, 0);
cx->time += idle_time;
return index;
}
/**
* acpi_idle_enter_bm - enters C3 with proper BM handling
* @dev: the target CPU
* @drv: cpuidle driver containing state data
* @index: the index of suggested state
*
* If BM is detected, the deepest non-C3 idle state is entered instead.
*/
static int acpi_idle_enter_bm(struct cpuidle_device *dev,
struct cpuidle_driver *drv, int index)
{
struct acpi_processor *pr;
struct acpi_processor_cx *cx = per_cpu(acpi_cstate[index], dev->cpu);
pr = __this_cpu_read(processors);
if (unlikely(!pr))
return -EINVAL;
if (!cx->bm_sts_skip && acpi_idle_bm_check()) {
if (drv->safe_state_index >= 0) {
return drv->states[drv->safe_state_index].enter(dev,
drv, drv->safe_state_index);
} else {
acpi_safe_halt();
return -EBUSY;
}
}
if (cx->entry_method == ACPI_CSTATE_FFH) {
if (current_set_polling_and_test())
return -EINVAL;
}
acpi_unlazy_tlb(smp_processor_id());
/* Tell the scheduler that we are going deep-idle: */
sched_clock_idle_sleep_event();
/*
* Must be done before busmaster disable as we might need to
* access HPET !
*/
lapic_timer_state_broadcast(pr, cx, 1);
/*
* disable bus master
* bm_check implies we need ARB_DIS
* !bm_check implies we need cache flush
* 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_check && 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);
} else if (!pr->flags.bm_check) {
ACPI_FLUSH_CPU_CACHE();
}
acpi_idle_do_entry(cx);
/* Re-enable bus master arbitration */
if (pr->flags.bm_check && 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);
}
sched_clock_idle_wakeup_event(0);
lapic_timer_state_broadcast(pr, cx, 0);
return index;
}
/**
* acpi_idle_enter_bm - enters C3 with proper BM handling
* @dev: the target CPU
* @state: the state data
*
* If BM is detected, the deepest non-C3 idle state is entered instead.
*/
static int acpi_idle_enter_bm(struct cpuidle_device *dev,
struct cpuidle_state *state)
{
struct acpi_processor *pr;
struct acpi_processor_cx *cx = cpuidle_get_statedata(state);
u32 t1, t2;
int sleep_ticks = 0;
pr = __get_cpu_var(processors);
if (unlikely(!pr))
return 0;
if (acpi_idle_suspend)
return(acpi_idle_enter_c1(dev, state));
if (acpi_idle_bm_check()) {
if (dev->safe_state) {
dev->last_state = dev->safe_state;
return dev->safe_state->enter(dev, dev->safe_state);
} else {
local_irq_disable();
acpi_safe_halt();
local_irq_enable();
return 0;
}
}
local_irq_disable();
current_thread_info()->status &= ~TS_POLLING;
/*
* TS_POLLING-cleared state must be visible before we test
* NEED_RESCHED:
*/
smp_mb();
if (unlikely(need_resched())) {
current_thread_info()->status |= TS_POLLING;
local_irq_enable();
return 0;
}
acpi_unlazy_tlb(smp_processor_id());
/* Tell the scheduler that we are going deep-idle: */
sched_clock_idle_sleep_event();
/*
* Must be done before busmaster disable as we might need to
* access HPET !
*/
acpi_state_timer_broadcast(pr, cx, 1);
/*
* disable bus master
* bm_check implies we need ARB_DIS
* !bm_check implies we need cache flush
* 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_check && pr->flags.bm_control) {
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_set_register(ACPI_BITREG_ARB_DISABLE, 1);
spin_unlock(&c3_lock);
} else if (!pr->flags.bm_check) {
ACPI_FLUSH_CPU_CACHE();
}
t1 = inl(acpi_gbl_FADT.xpm_timer_block.address);
acpi_idle_do_entry(cx);
t2 = inl(acpi_gbl_FADT.xpm_timer_block.address);
/* Re-enable bus master arbitration */
if (pr->flags.bm_check && pr->flags.bm_control) {
spin_lock(&c3_lock);
acpi_set_register(ACPI_BITREG_ARB_DISABLE, 0);
c3_cpu_count--;
spin_unlock(&c3_lock);
}
#if defined (CONFIG_GENERIC_TIME) && defined (CONFIG_X86)
/* TSC could halt in idle, so notify users */
if (tsc_halts_in_c(ACPI_STATE_C3))
mark_tsc_unstable("TSC halts in idle");
#endif
sleep_ticks = ticks_elapsed(t1, t2);
/* Tell the scheduler how much we idled: */
sched_clock_idle_wakeup_event(sleep_ticks*PM_TIMER_TICK_NS);
local_irq_enable();
current_thread_info()->status |= TS_POLLING;
cx->usage++;
acpi_state_timer_broadcast(pr, cx, 0);
cx->time += sleep_ticks;
return ticks_elapsed_in_us(t1, t2);
}
