Commit e4cb0c9e authored by Rafael J. Wysocki's avatar Rafael J. Wysocki

Merge branch 'pm-genirq' into acpi-pm

parents 905563ff 27f3d186
System Suspend and Device Interrupts
Copyright (C) 2014 Intel Corp.
Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Suspending and Resuming Device IRQs
-----------------------------------
Device interrupt request lines (IRQs) are generally disabled during system
suspend after the "late" phase of suspending devices (that is, after all of the
->prepare, ->suspend and ->suspend_late callbacks have been executed for all
devices). That is done by suspend_device_irqs().
The rationale for doing so is that after the "late" phase of device suspend
there is no legitimate reason why any interrupts from suspended devices should
trigger and if any devices have not been suspended properly yet, it is better to
block interrupts from them anyway. Also, in the past we had problems with
interrupt handlers for shared IRQs that device drivers implementing them were
not prepared for interrupts triggering after their devices had been suspended.
In some cases they would attempt to access, for example, memory address spaces
of suspended devices and cause unpredictable behavior to ensue as a result.
Unfortunately, such problems are very difficult to debug and the introduction
of suspend_device_irqs(), along with the "noirq" phase of device suspend and
resume, was the only practical way to mitigate them.
Device IRQs are re-enabled during system resume, right before the "early" phase
of resuming devices (that is, before starting to execute ->resume_early
callbacks for devices). The function doing that is resume_device_irqs().
The IRQF_NO_SUSPEND Flag
------------------------
There are interrupts that can legitimately trigger during the entire system
suspend-resume cycle, including the "noirq" phases of suspending and resuming
devices as well as during the time when nonboot CPUs are taken offline and
brought back online. That applies to timer interrupts in the first place,
but also to IPIs and to some other special-purpose interrupts.
The IRQF_NO_SUSPEND flag is used to indicate that to the IRQ subsystem when
requesting a special-purpose interrupt. It causes suspend_device_irqs() to
leave the corresponding IRQ enabled so as to allow the interrupt to work all
the time as expected.
Note that the IRQF_NO_SUSPEND flag affects the entire IRQ and not just one
user of it. Thus, if the IRQ is shared, all of the interrupt handlers installed
for it will be executed as usual after suspend_device_irqs(), even if the
IRQF_NO_SUSPEND flag was not passed to request_irq() (or equivalent) by some of
the IRQ's users. For this reason, using IRQF_NO_SUSPEND and IRQF_SHARED at the
same time should be avoided.
System Wakeup Interrupts, enable_irq_wake() and disable_irq_wake()
------------------------------------------------------------------
System wakeup interrupts generally need to be configured to wake up the system
from sleep states, especially if they are used for different purposes (e.g. as
I/O interrupts) in the working state.
That may involve turning on a special signal handling logic within the platform
(such as an SoC) so that signals from a given line are routed in a different way
during system sleep so as to trigger a system wakeup when needed. For example,
the platform may include a dedicated interrupt controller used specifically for
handling system wakeup events. Then, if a given interrupt line is supposed to
wake up the system from sleep sates, the corresponding input of that interrupt
controller needs to be enabled to receive signals from the line in question.
After wakeup, it generally is better to disable that input to prevent the
dedicated controller from triggering interrupts unnecessarily.
The IRQ subsystem provides two helper functions to be used by device drivers for
those purposes. Namely, enable_irq_wake() turns on the platform's logic for
handling the given IRQ as a system wakeup interrupt line and disable_irq_wake()
turns that logic off.
Calling enable_irq_wake() causes suspend_device_irqs() to treat the given IRQ
in a special way. Namely, the IRQ remains enabled, by on the first interrupt
it will be disabled, marked as pending and "suspended" so that it will be
re-enabled by resume_device_irqs() during the subsequent system resume. Also
the PM core is notified about the event which casues the system suspend in
progress to be aborted (that doesn't have to happen immediately, but at one
of the points where the suspend thread looks for pending wakeup events).
This way every interrupt from a wakeup interrupt source will either cause the
system suspend currently in progress to be aborted or wake up the system if
already suspended. However, after suspend_device_irqs() interrupt handlers are
not executed for system wakeup IRQs. They are only executed for IRQF_NO_SUSPEND
IRQs at that time, but those IRQs should not be configured for system wakeup
using enable_irq_wake().
Interrupts and Suspend-to-Idle
------------------------------
Suspend-to-idle (also known as the "freeze" sleep state) is a relatively new
system sleep state that works by idling all of the processors and waiting for
interrupts right after the "noirq" phase of suspending devices.
Of course, this means that all of the interrupts with the IRQF_NO_SUSPEND flag
set will bring CPUs out of idle while in that state, but they will not cause the
IRQ subsystem to trigger a system wakeup.
System wakeup interrupts, in turn, will trigger wakeup from suspend-to-idle in
analogy with what they do in the full system suspend case. The only difference
is that the wakeup from suspend-to-idle is signaled using the usual working
state interrupt delivery mechanisms and doesn't require the platform to use
any special interrupt handling logic for it to work.
IRQF_NO_SUSPEND and enable_irq_wake()
-------------------------------------
There are no valid reasons to use both enable_irq_wake() and the IRQF_NO_SUSPEND
flag on the same IRQ.
First of all, if the IRQ is not shared, the rules for handling IRQF_NO_SUSPEND
interrupts (interrupt handlers are invoked after suspend_device_irqs()) are
directly at odds with the rules for handling system wakeup interrupts (interrupt
handlers are not invoked after suspend_device_irqs()).
Second, both enable_irq_wake() and IRQF_NO_SUSPEND apply to entire IRQs and not
to individual interrupt handlers, so sharing an IRQ between a system wakeup
interrupt source and an IRQF_NO_SUSPEND interrupt source does not make sense.
......@@ -2623,6 +2623,7 @@ static struct irq_chip ioapic_chip __read_mostly = {
.irq_eoi = ack_apic_level,
.irq_set_affinity = native_ioapic_set_affinity,
.irq_retrigger = ioapic_retrigger_irq,
.flags = IRQCHIP_SKIP_SET_WAKE,
};
static inline void init_IO_APIC_traps(void)
......@@ -3173,6 +3174,7 @@ static struct irq_chip msi_chip = {
.irq_ack = ack_apic_edge,
.irq_set_affinity = msi_set_affinity,
.irq_retrigger = ioapic_retrigger_irq,
.flags = IRQCHIP_SKIP_SET_WAKE,
};
int setup_msi_irq(struct pci_dev *dev, struct msi_desc *msidesc,
......@@ -3271,6 +3273,7 @@ static struct irq_chip dmar_msi_type = {
.irq_ack = ack_apic_edge,
.irq_set_affinity = dmar_msi_set_affinity,
.irq_retrigger = ioapic_retrigger_irq,
.flags = IRQCHIP_SKIP_SET_WAKE,
};
int arch_setup_dmar_msi(unsigned int irq)
......@@ -3321,6 +3324,7 @@ static struct irq_chip hpet_msi_type = {
.irq_ack = ack_apic_edge,
.irq_set_affinity = hpet_msi_set_affinity,
.irq_retrigger = ioapic_retrigger_irq,
.flags = IRQCHIP_SKIP_SET_WAKE,
};
int default_setup_hpet_msi(unsigned int irq, unsigned int id)
......@@ -3384,6 +3388,7 @@ static struct irq_chip ht_irq_chip = {
.irq_ack = ack_apic_edge,
.irq_set_affinity = ht_set_affinity,
.irq_retrigger = ioapic_retrigger_irq,
.flags = IRQCHIP_SKIP_SET_WAKE,
};
int arch_setup_ht_irq(unsigned int irq, struct pci_dev *dev)
......
......@@ -24,6 +24,9 @@
*/
bool events_check_enabled __read_mostly;
/* If set and the system is suspending, terminate the suspend. */
static bool pm_abort_suspend __read_mostly;
/*
* Combined counters of registered wakeup events and wakeup events in progress.
* They need to be modified together atomically, so it's better to use one
......@@ -719,7 +722,18 @@ bool pm_wakeup_pending(void)
pm_print_active_wakeup_sources();
}
return ret;
return ret || pm_abort_suspend;
}
void pm_system_wakeup(void)
{
pm_abort_suspend = true;
freeze_wake();
}
void pm_wakeup_clear(void)
{
pm_abort_suspend = false;
}
/**
......
......@@ -9,7 +9,7 @@
#include <linux/syscore_ops.h>
#include <linux/mutex.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/suspend.h>
#include <trace/events/power.h>
static LIST_HEAD(syscore_ops_list);
......@@ -54,9 +54,8 @@ int syscore_suspend(void)
pr_debug("Checking wakeup interrupts\n");
/* Return error code if there are any wakeup interrupts pending. */
ret = check_wakeup_irqs();
if (ret)
return ret;
if (pm_wakeup_pending())
return -EBUSY;
WARN_ONCE(!irqs_disabled(),
"Interrupts enabled before system core suspend.\n");
......
......@@ -41,11 +41,17 @@ static int __init pcie_pme_setup(char *str)
}
__setup("pcie_pme=", pcie_pme_setup);
enum pme_suspend_level {
PME_SUSPEND_NONE = 0,
PME_SUSPEND_WAKEUP,
PME_SUSPEND_NOIRQ,
};
struct pcie_pme_service_data {
spinlock_t lock;
struct pcie_device *srv;
struct work_struct work;
bool noirq; /* Don't enable the PME interrupt used by this service. */
enum pme_suspend_level suspend_level;
};
/**
......@@ -223,7 +229,7 @@ static void pcie_pme_work_fn(struct work_struct *work)
spin_lock_irq(&data->lock);
for (;;) {
if (data->noirq)
if (data->suspend_level != PME_SUSPEND_NONE)
break;
pcie_capability_read_dword(port, PCI_EXP_RTSTA, &rtsta);
......@@ -250,7 +256,7 @@ static void pcie_pme_work_fn(struct work_struct *work)
spin_lock_irq(&data->lock);
}
if (!data->noirq)
if (data->suspend_level == PME_SUSPEND_NONE)
pcie_pme_interrupt_enable(port, true);
spin_unlock_irq(&data->lock);
......@@ -367,6 +373,21 @@ static int pcie_pme_probe(struct pcie_device *srv)
return ret;
}
static bool pcie_pme_check_wakeup(struct pci_bus *bus)
{
struct pci_dev *dev;
if (!bus)
return false;
list_for_each_entry(dev, &bus->devices, bus_list)
if (device_may_wakeup(&dev->dev)
|| pcie_pme_check_wakeup(dev->subordinate))
return true;
return false;
}
/**
* pcie_pme_suspend - Suspend PCIe PME service device.
* @srv: PCIe service device to suspend.
......@@ -375,11 +396,26 @@ static int pcie_pme_suspend(struct pcie_device *srv)
{
struct pcie_pme_service_data *data = get_service_data(srv);
struct pci_dev *port = srv->port;
bool wakeup;
if (device_may_wakeup(&port->dev)) {
wakeup = true;
} else {
down_read(&pci_bus_sem);
wakeup = pcie_pme_check_wakeup(port->subordinate);
up_read(&pci_bus_sem);
}
spin_lock_irq(&data->lock);
if (wakeup) {
enable_irq_wake(srv->irq);
data->suspend_level = PME_SUSPEND_WAKEUP;
} else {
struct pci_dev *port = srv->port;
pcie_pme_interrupt_enable(port, false);
pcie_clear_root_pme_status(port);
data->noirq = true;
data->suspend_level = PME_SUSPEND_NOIRQ;
}
spin_unlock_irq(&data->lock);
synchronize_irq(srv->irq);
......@@ -394,12 +430,17 @@ static int pcie_pme_suspend(struct pcie_device *srv)
static int pcie_pme_resume(struct pcie_device *srv)
{
struct pcie_pme_service_data *data = get_service_data(srv);
struct pci_dev *port = srv->port;
spin_lock_irq(&data->lock);
data->noirq = false;
if (data->suspend_level == PME_SUSPEND_NOIRQ) {
struct pci_dev *port = srv->port;
pcie_clear_root_pme_status(port);
pcie_pme_interrupt_enable(port, true);
} else {
disable_irq_wake(srv->irq);
}
data->suspend_level = PME_SUSPEND_NONE;
spin_unlock_irq(&data->lock);
return 0;
......
......@@ -193,11 +193,6 @@ extern void irq_wake_thread(unsigned int irq, void *dev_id);
/* The following three functions are for the core kernel use only. */
extern void suspend_device_irqs(void);
extern void resume_device_irqs(void);
#ifdef CONFIG_PM_SLEEP
extern int check_wakeup_irqs(void);
#else
static inline int check_wakeup_irqs(void) { return 0; }
#endif
/**
* struct irq_affinity_notify - context for notification of IRQ affinity changes
......
......@@ -173,6 +173,7 @@ struct irq_data {
* IRQD_IRQ_DISABLED - Disabled state of the interrupt
* IRQD_IRQ_MASKED - Masked state of the interrupt
* IRQD_IRQ_INPROGRESS - In progress state of the interrupt
* IRQD_WAKEUP_ARMED - Wakeup mode armed
*/
enum {
IRQD_TRIGGER_MASK = 0xf,
......@@ -186,6 +187,7 @@ enum {
IRQD_IRQ_DISABLED = (1 << 16),
IRQD_IRQ_MASKED = (1 << 17),
IRQD_IRQ_INPROGRESS = (1 << 18),
IRQD_WAKEUP_ARMED = (1 << 19),
};
static inline bool irqd_is_setaffinity_pending(struct irq_data *d)
......@@ -257,6 +259,12 @@ static inline bool irqd_irq_inprogress(struct irq_data *d)
return d->state_use_accessors & IRQD_IRQ_INPROGRESS;
}
static inline bool irqd_is_wakeup_armed(struct irq_data *d)
{
return d->state_use_accessors & IRQD_WAKEUP_ARMED;
}
/*
* Functions for chained handlers which can be enabled/disabled by the
* standard disable_irq/enable_irq calls. Must be called with
......
......@@ -36,6 +36,11 @@ struct irq_desc;
* @threads_oneshot: bitfield to handle shared oneshot threads
* @threads_active: number of irqaction threads currently running
* @wait_for_threads: wait queue for sync_irq to wait for threaded handlers
* @nr_actions: number of installed actions on this descriptor
* @no_suspend_depth: number of irqactions on a irq descriptor with
* IRQF_NO_SUSPEND set
* @force_resume_depth: number of irqactions on a irq descriptor with
* IRQF_FORCE_RESUME set
* @dir: /proc/irq/ procfs entry
* @name: flow handler name for /proc/interrupts output
*/
......@@ -68,6 +73,11 @@ struct irq_desc {
unsigned long threads_oneshot;
atomic_t threads_active;
wait_queue_head_t wait_for_threads;
#ifdef CONFIG_PM_SLEEP
unsigned int nr_actions;
unsigned int no_suspend_depth;
unsigned int force_resume_depth;
#endif
#ifdef CONFIG_PROC_FS
struct proc_dir_entry *dir;
#endif
......
......@@ -371,6 +371,8 @@ extern int unregister_pm_notifier(struct notifier_block *nb);
extern bool events_check_enabled;
extern bool pm_wakeup_pending(void);
extern void pm_system_wakeup(void);
extern void pm_wakeup_clear(void);
extern bool pm_get_wakeup_count(unsigned int *count, bool block);
extern bool pm_save_wakeup_count(unsigned int count);
extern void pm_wakep_autosleep_enabled(bool set);
......@@ -418,6 +420,8 @@ static inline int unregister_pm_notifier(struct notifier_block *nb)
#define pm_notifier(fn, pri) do { (void)(fn); } while (0)
static inline bool pm_wakeup_pending(void) { return false; }
static inline void pm_system_wakeup(void) {}
static inline void pm_wakeup_clear(void) {}
static inline void lock_system_sleep(void) {}
static inline void unlock_system_sleep(void) {}
......
......@@ -342,6 +342,31 @@ static bool irq_check_poll(struct irq_desc *desc)
return irq_wait_for_poll(desc);
}
static bool irq_may_run(struct irq_desc *desc)
{
unsigned int mask = IRQD_IRQ_INPROGRESS | IRQD_WAKEUP_ARMED;
/*
* If the interrupt is not in progress and is not an armed
* wakeup interrupt, proceed.
*/
if (!irqd_has_set(&desc->irq_data, mask))
return true;
/*
* If the interrupt is an armed wakeup source, mark it pending
* and suspended, disable it and notify the pm core about the
* event.
*/
if (irq_pm_check_wakeup(desc))
return false;
/*
* Handle a potential concurrent poll on a different core.
*/
return irq_check_poll(desc);
}
/**
* handle_simple_irq - Simple and software-decoded IRQs.
* @irq: the interrupt number
......@@ -359,8 +384,7 @@ handle_simple_irq(unsigned int irq, struct irq_desc *desc)
{
raw_spin_lock(&desc->lock);
if (unlikely(irqd_irq_inprogress(&desc->irq_data)))
if (!irq_check_poll(desc))
if (!irq_may_run(desc))
goto out_unlock;
desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
......@@ -412,8 +436,7 @@ handle_level_irq(unsigned int irq, struct irq_desc *desc)
raw_spin_lock(&desc->lock);
mask_ack_irq(desc);
if (unlikely(irqd_irq_inprogress(&desc->irq_data)))
if (!irq_check_poll(desc))
if (!irq_may_run(desc))
goto out_unlock;
desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
......@@ -485,8 +508,7 @@ handle_fasteoi_irq(unsigned int irq, struct irq_desc *desc)
raw_spin_lock(&desc->lock);
if (unlikely(irqd_irq_inprogress(&desc->irq_data)))
if (!irq_check_poll(desc))
if (!irq_may_run(desc))
goto out;
desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
......@@ -541,19 +563,23 @@ handle_edge_irq(unsigned int irq, struct irq_desc *desc)
raw_spin_lock(&desc->lock);
desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
if (!irq_may_run(desc)) {
desc->istate |= IRQS_PENDING;
mask_ack_irq(desc);
goto out_unlock;
}
/*
* If we're currently running this IRQ, or its disabled,
* we shouldn't process the IRQ. Mark it pending, handle
* the necessary masking and go out
* If its disabled or no action available then mask it and get
* out of here.
*/
if (unlikely(irqd_irq_disabled(&desc->irq_data) ||
irqd_irq_inprogress(&desc->irq_data) || !desc->action)) {
if (!irq_check_poll(desc)) {
if (irqd_irq_disabled(&desc->irq_data) || !desc->action) {
desc->istate |= IRQS_PENDING;
mask_ack_irq(desc);
goto out_unlock;
}
}
kstat_incr_irqs_this_cpu(irq, desc);
/* Start handling the irq */
......@@ -602,18 +628,21 @@ void handle_edge_eoi_irq(unsigned int irq, struct irq_desc *desc)
raw_spin_lock(&desc->lock);
desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
if (!irq_may_run(desc)) {
desc->istate |= IRQS_PENDING;
goto out_eoi;
}
/*
* If we're currently running this IRQ, or its disabled,
* we shouldn't process the IRQ. Mark it pending, handle
* the necessary masking and go out
* If its disabled or no action available then mask it and get
* out of here.
*/
if (unlikely(irqd_irq_disabled(&desc->irq_data) ||
irqd_irq_inprogress(&desc->irq_data) || !desc->action)) {
if (!irq_check_poll(desc)) {
if (irqd_irq_disabled(&desc->irq_data) || !desc->action) {
desc->istate |= IRQS_PENDING;
goto out_eoi;
}
}
kstat_incr_irqs_this_cpu(irq, desc);
do {
......
......@@ -63,8 +63,8 @@ enum {
extern int __irq_set_trigger(struct irq_desc *desc, unsigned int irq,
unsigned long flags);
extern void __disable_irq(struct irq_desc *desc, unsigned int irq, bool susp);
extern void __enable_irq(struct irq_desc *desc, unsigned int irq, bool resume);
extern void __disable_irq(struct irq_desc *desc, unsigned int irq);
extern void __enable_irq(struct irq_desc *desc, unsigned int irq);
extern int irq_startup(struct irq_desc *desc, bool resend);
extern void irq_shutdown(struct irq_desc *desc);
......@@ -194,3 +194,15 @@ static inline void kstat_incr_irqs_this_cpu(unsigned int irq, struct irq_desc *d
__this_cpu_inc(*desc->kstat_irqs);
__this_cpu_inc(kstat.irqs_sum);
}
#ifdef CONFIG_PM_SLEEP
bool irq_pm_check_wakeup(struct irq_desc *desc);
void irq_pm_install_action(struct irq_desc *desc, struct irqaction *action);
void irq_pm_remove_action(struct irq_desc *desc, struct irqaction *action);
#else
static inline bool irq_pm_check_wakeup(struct irq_desc *desc) { return false; }
static inline void
irq_pm_install_action(struct irq_desc *desc, struct irqaction *action) { }
static inline void
irq_pm_remove_action(struct irq_desc *desc, struct irqaction *action) { }
#endif
......@@ -382,14 +382,8 @@ setup_affinity(unsigned int irq, struct irq_desc *desc, struct cpumask *mask)
}
#endif
void __disable_irq(struct irq_desc *desc, unsigned int irq, bool suspend)
void __disable_irq(struct irq_desc *desc, unsigned int irq)
{
if (suspend) {
if (!desc->action || (desc->action->flags & IRQF_NO_SUSPEND))
return;
desc->istate |= IRQS_SUSPENDED;
}
if (!desc->depth++)
irq_disable(desc);
}
......@@ -401,7 +395,7 @@ static int __disable_irq_nosync(unsigned int irq)
if (!desc)
return -EINVAL;
__disable_irq(desc, irq, false);
__disable_irq(desc, irq);
irq_put_desc_busunlock(desc, flags);
return 0;
}
......@@ -442,20 +436,8 @@ void disable_irq(unsigned int irq)
}
EXPORT_SYMBOL(disable_irq);
void __enable_irq(struct irq_desc *desc, unsigned int irq, bool resume)
void __enable_irq(struct irq_desc *desc, unsigned int irq)
{
if (resume) {
if (!(desc->istate & IRQS_SUSPENDED)) {
if (!desc->action)
return;
if (!(desc->action->flags & IRQF_FORCE_RESUME))
return;
/* Pretend that it got disabled ! */
desc->depth++;
}
desc->istate &= ~IRQS_SUSPENDED;
}
switch (desc->depth) {
case 0:
err_out:
......@@ -497,7 +479,7 @@ void enable_irq(unsigned int irq)
KERN_ERR "enable_irq before setup/request_irq: irq %u\n", irq))
goto out;
__enable_irq(desc, irq, false);
__enable_irq(desc, irq);
out:
irq_put_desc_busunlock(desc, flags);
}
......@@ -1218,6 +1200,8 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
new->irq = irq;
*old_ptr = new;
irq_pm_install_action(desc, new);
/* Reset broken irq detection when installing new handler */
desc->irq_count = 0;
desc->irqs_unhandled = 0;
......@@ -1228,7 +1212,7 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
*/
if (shared && (desc->istate & IRQS_SPURIOUS_DISABLED)) {
desc->istate &= ~IRQS_SPURIOUS_DISABLED;
__enable_irq(desc, irq, false);
__enable_irq(desc, irq);
}
raw_spin_unlock_irqrestore(&desc->lock, flags);
......@@ -1336,6 +1320,8 @@ static struct irqaction *__free_irq(unsigned int irq, void *dev_id)
/* Found it - now remove it from the list of entries: */
*action_ptr = action->next;
irq_pm_remove_action(desc, action);
/* If this was the last handler, shut down the IRQ line: */
if (!desc->action) {
irq_shutdown(desc);
......
......@@ -9,17 +9,105 @@
#include <linux/irq.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/suspend.h>
#include <linux/syscore_ops.h>
#include "internals.h"
bool irq_pm_check_wakeup(struct irq_desc *desc)
{
if (irqd_is_wakeup_armed(&desc->irq_data)) {
irqd_clear(&desc->irq_data, IRQD_WAKEUP_ARMED);
desc->istate |= IRQS_SUSPENDED | IRQS_PENDING;
desc->depth++;
irq_disable(desc);
pm_system_wakeup();
return true;
}
return false;
}
/*
* Called from __setup_irq() with desc->lock held after @action has
* been installed in the action chain.
*/
void irq_pm_install_action(struct irq_desc *desc, struct irqaction *action)
{
desc->nr_actions++;
if (action->flags & IRQF_FORCE_RESUME)
desc->force_resume_depth++;
WARN_ON_ONCE(desc->force_resume_depth &&
desc->force_resume_depth != desc->nr_actions);
if (action->flags & IRQF_NO_SUSPEND)
desc->no_suspend_depth++;
WARN_ON_ONCE(desc->no_suspend_depth &&
desc->no_suspend_depth != desc->nr_actions);
}
/*
* Called from __free_irq() with desc->lock held after @action has
* been removed from the action chain.
*/
void irq_pm_remove_action(struct irq_desc *desc, struct irqaction *action)
{
desc->nr_actions--;
if (action->flags & IRQF_FORCE_RESUME)
desc->force_resume_depth--;
if (action->flags & IRQF_NO_SUSPEND)
desc->no_suspend_depth--;
}
static bool suspend_device_irq(struct irq_desc *desc, int irq)
{
if (!desc->action || desc->no_suspend_depth)
return false;
if (irqd_is_wakeup_set(&desc->irq_data)) {
irqd_set(&desc->irq_data, IRQD_WAKEUP_ARMED);
/*
* We return true here to force the caller to issue
* synchronize_irq(). We need to make sure that the
* IRQD_WAKEUP_ARMED is visible before we return from
* suspend_device_irqs().
*/
return true;
}
desc->istate |= IRQS_SUSPENDED;
__disable_irq(desc, irq);
/*
* Hardware which has no wakeup source configuration facility
* requires that the non wakeup interrupts are masked at the
* chip level. The chip implementation indicates that with
* IRQCHIP_MASK_ON_SUSPEND.
*/
if (irq_desc_get_chip(desc)->flags & IRQCHIP_MASK_ON_SUSPEND)
mask_irq(desc);
return true;
}
/**
* suspend_device_irqs - disable all currently enabled interrupt lines
*
* During system-wide suspend or hibernation device drivers need to be prevented
* from receiving interrupts and this function is provided for this purpose.
* It marks all interrupt lines in use, except for the timer ones, as disabled
* and sets the IRQS_SUSPENDED flag for each of them.
* During system-wide suspend or hibernation device drivers need to be
* prevented from receiving interrupts and this function is provided
* for this purpose.
*
* So we disable all interrupts and mark them IRQS_SUSPENDED except
* for those which are unused, those which are marked as not
* suspendable via an interrupt request with the flag IRQF_NO_SUSPEND
* set and those which are marked as active wakeup sources.
*
* The active wakeup sources are handled by the flow handler entry
* code which checks for the IRQD_WAKEUP_ARMED flag, suspends the
* interrupt and notifies the pm core about the wakeup.
*/
void suspend_device_irqs(void)
{
......@@ -28,18 +116,36 @@ void suspend_device_irqs(void)
for_each_irq_desc(irq, desc) {
unsigned long flags;
bool sync;
raw_spin_lock_irqsave(&desc->lock, flags);
__disable_irq(desc, irq, true);
sync = suspend_device_irq(desc, irq);
raw_spin_unlock_irqrestore(&desc->lock, flags);
}
for_each_irq_desc(irq, desc)
if (desc->istate & IRQS_SUSPENDED)
if (sync)
synchronize_irq(irq);
}
}
EXPORT_SYMBOL_GPL(suspend_device_irqs);
static void resume_irq(struct irq_desc *desc, int irq)
{
irqd_clear(&desc->irq_data, IRQD_WAKEUP_ARMED);
if (desc->istate & IRQS_SUSPENDED)
goto resume;
/* Force resume the interrupt? */
if (!desc->force_resume_depth)
return;
/* Pretend that it got disabled ! */
desc->depth++;
resume:
desc->istate &= ~IRQS_SUSPENDED;
__enable_irq(desc, irq);
}
static void resume_irqs(bool want_early)
{
struct irq_desc *desc;
......@@ -54,7 +160,7 @@ static void resume_irqs(bool want_early)
continue;
raw_spin_lock_irqsave(&desc->lock, flags);
__enable_irq(desc, irq, true);
resume_irq(desc, irq);
raw_spin_unlock_irqrestore(&desc->lock, flags);
}
}
......@@ -93,38 +199,3 @@ void resume_device_irqs(void)
resume_irqs(false);
}
EXPORT_SYMBOL_GPL(resume_device_irqs);
/**
* check_wakeup_irqs - check if any wake-up interrupts are pending
*/
int check_wakeup_irqs(void)
{
struct irq_desc *desc;
int irq;
for_each_irq_desc(irq, desc) {
/*
* Only interrupts which are marked as wakeup source
* and have not been disabled before the suspend check
* can abort suspend.
*/
if (irqd_is_wakeup_set(&desc->irq_data)) {
if (desc->depth == 1 && desc->istate & IRQS_PENDING)
return -EBUSY;
continue;
}
/*
* Check the non wakeup interrupts whether they need
* to be masked before finally going into suspend
* state. That's for hardware which has no wakeup
* source configuration facility. The chip
* implementation indicates that with
* IRQCHIP_MASK_ON_SUSPEND.
*/
if (desc->istate & IRQS_SUSPENDED &&
irq_desc_get_chip(desc)->flags & IRQCHIP_MASK_ON_SUSPEND)
mask_irq(desc);
}
return 0;
}
......@@ -129,6 +129,7 @@ int freeze_processes(void)
if (!pm_freezing)
atomic_inc(&system_freezing_cnt);
pm_wakeup_clear();
printk("Freezing user space processes ... ");
pm_freezing = true;
error = try_to_freeze_tasks(true);
......
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