Orange Pi5 kernel

// SPDX-License-Identifier: GPL-2.0-only
/*
 * kernel/power/suspend.c - Suspend to RAM and standby functionality.
 *
 * Copyright (c) 2003 Patrick Mochel
 * Copyright (c) 2003 Open Source Development Lab
 * Copyright (c) 2009 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc.
 */
 
#define pr_fmt(fmt) "PM: " fmt
 
#include <linux/string.h>
#include <linux/delay.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/console.h>
#include <linux/cpu.h>
#include <linux/cpuidle.h>
#include <linux/gfp.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/export.h>
#include <linux/suspend.h>
#include <linux/syscore_ops.h>
#include <linux/swait.h>
#include <linux/ftrace.h>
#include <trace/events/power.h>
#include <linux/compiler.h>
#include <linux/moduleparam.h>
#include <linux/wakeup_reason.h>
 
#include "power.h"
 
const char * const pm_labels[] = {
<------>[PM_SUSPEND_TO_IDLE] = "freeze",
<------>[PM_SUSPEND_STANDBY] = "standby",
<------>[PM_SUSPEND_MEM] = "mem",
};
const char *pm_states[PM_SUSPEND_MAX];
static const char * const mem_sleep_labels[] = {
<------>[PM_SUSPEND_TO_IDLE] = "s2idle",
<------>[PM_SUSPEND_STANDBY] = "shallow",
<------>[PM_SUSPEND_MEM] = "deep",
};
const char *mem_sleep_states[PM_SUSPEND_MAX];
 
suspend_state_t mem_sleep_current = PM_SUSPEND_TO_IDLE;
suspend_state_t mem_sleep_default = PM_SUSPEND_MAX;
suspend_state_t pm_suspend_target_state;
EXPORT_SYMBOL_GPL(pm_suspend_target_state);
 
unsigned int pm_suspend_global_flags;
EXPORT_SYMBOL_GPL(pm_suspend_global_flags);
 
static const struct platform_suspend_ops *suspend_ops;
static const struct platform_s2idle_ops *s2idle_ops;
static DECLARE_SWAIT_QUEUE_HEAD(s2idle_wait_head);
 
enum s2idle_states __read_mostly s2idle_state;
static DEFINE_RAW_SPINLOCK(s2idle_lock);
 
/**
 * pm_suspend_default_s2idle - Check if suspend-to-idle is the default suspend.
 *
 * Return 'true' if suspend-to-idle has been selected as the default system
 * suspend method.
 */
bool pm_suspend_default_s2idle(void)
{
<------>return mem_sleep_current == PM_SUSPEND_TO_IDLE;
}
EXPORT_SYMBOL_GPL(pm_suspend_default_s2idle);
 
void s2idle_set_ops(const struct platform_s2idle_ops *ops)
{
<------>lock_system_sleep();
<------>s2idle_ops = ops;
<------>unlock_system_sleep();
}
 
static void s2idle_begin(void)
{
<------>s2idle_state = S2IDLE_STATE_NONE;
}
 
static void s2idle_enter(void)
{
<------>trace_suspend_resume(TPS("machine_suspend"), PM_SUSPEND_TO_IDLE, true);
 
<------>raw_spin_lock_irq(&s2idle_lock);
<------>if (pm_wakeup_pending())
<------><------>goto out;
 
<------>s2idle_state = S2IDLE_STATE_ENTER;
<------>raw_spin_unlock_irq(&s2idle_lock);
 
<------>get_online_cpus();
<------>cpuidle_resume();
 
<------>/* Push all the CPUs into the idle loop. */
<------>wake_up_all_idle_cpus();
<------>/* Make the current CPU wait so it can enter the idle loop too. */
<------>swait_event_exclusive(s2idle_wait_head,
<------><------>    s2idle_state == S2IDLE_STATE_WAKE);
 
<------>cpuidle_pause();
<------>put_online_cpus();
 
<------>raw_spin_lock_irq(&s2idle_lock);
 
 out:
<------>s2idle_state = S2IDLE_STATE_NONE;
<------>raw_spin_unlock_irq(&s2idle_lock);
 
<------>trace_suspend_resume(TPS("machine_suspend"), PM_SUSPEND_TO_IDLE, false);
}
 
static void s2idle_loop(void)
{
<------>pm_pr_dbg("suspend-to-idle\n");
 
<------>/*
<------> * Suspend-to-idle equals:
<------> * frozen processes + suspended devices + idle processors.
<------> * Thus s2idle_enter() should be called right after all devices have
<------> * been suspended.
<------> *
<------> * Wakeups during the noirq suspend of devices may be spurious, so try
<------> * to avoid them upfront.
<------> */
<------>for (;;) {
<------><------>if (s2idle_ops && s2idle_ops->wake) {
<------><------><------>if (s2idle_ops->wake())
<------><------><------><------>break;
<------><------>} else if (pm_wakeup_pending()) {
<------><------><------>break;
<------><------>}
 
<------><------>clear_wakeup_reasons();
<------><------>s2idle_enter();
<------>}
 
<------>pm_pr_dbg("resume from suspend-to-idle\n");
}
 
void s2idle_wake(void)
{
<------>unsigned long flags;
 
<------>raw_spin_lock_irqsave(&s2idle_lock, flags);
<------>if (s2idle_state > S2IDLE_STATE_NONE) {
<------><------>s2idle_state = S2IDLE_STATE_WAKE;
<------><------>swake_up_one(&s2idle_wait_head);
<------>}
<------>raw_spin_unlock_irqrestore(&s2idle_lock, flags);
}
EXPORT_SYMBOL_GPL(s2idle_wake);
 
static bool valid_state(suspend_state_t state)
{
<------>/*
<------> * PM_SUSPEND_STANDBY and PM_SUSPEND_MEM states need low level
<------> * support and need to be valid to the low level
<------> * implementation, no valid callback implies that none are valid.
<------> */
<------>return suspend_ops && suspend_ops->valid && suspend_ops->valid(state);
}
 
void __init pm_states_init(void)
{
<------>/* "mem" and "freeze" are always present in /sys/power/state. */
<------>pm_states[PM_SUSPEND_MEM] = pm_labels[PM_SUSPEND_MEM];
<------>pm_states[PM_SUSPEND_TO_IDLE] = pm_labels[PM_SUSPEND_TO_IDLE];
<------>/*
<------> * Suspend-to-idle should be supported even without any suspend_ops,
<------> * initialize mem_sleep_states[] accordingly here.
<------> */
<------>mem_sleep_states[PM_SUSPEND_TO_IDLE] = mem_sleep_labels[PM_SUSPEND_TO_IDLE];
}
 
static int __init mem_sleep_default_setup(char *str)
{
<------>suspend_state_t state;
 
<------>for (state = PM_SUSPEND_TO_IDLE; state <= PM_SUSPEND_MEM; state++)
<------><------>if (mem_sleep_labels[state] &&
<------><------>    !strcmp(str, mem_sleep_labels[state])) {
<------><------><------>mem_sleep_default = state;
<------><------><------>break;
<------><------>}
 
<------>return 1;
}
__setup("mem_sleep_default=", mem_sleep_default_setup);
 
/**
 * suspend_set_ops - Set the global suspend method table.
 * @ops: Suspend operations to use.
 */
void suspend_set_ops(const struct platform_suspend_ops *ops)
{
<------>lock_system_sleep();
 
<------>suspend_ops = ops;
 
<------>if (valid_state(PM_SUSPEND_STANDBY)) {
<------><------>mem_sleep_states[PM_SUSPEND_STANDBY] = mem_sleep_labels[PM_SUSPEND_STANDBY];
<------><------>pm_states[PM_SUSPEND_STANDBY] = pm_labels[PM_SUSPEND_STANDBY];
<------><------>if (mem_sleep_default == PM_SUSPEND_STANDBY)
<------><------><------>mem_sleep_current = PM_SUSPEND_STANDBY;
<------>}
<------>if (valid_state(PM_SUSPEND_MEM)) {
<------><------>mem_sleep_states[PM_SUSPEND_MEM] = mem_sleep_labels[PM_SUSPEND_MEM];
<------><------>if (mem_sleep_default >= PM_SUSPEND_MEM)
<------><------><------>mem_sleep_current = PM_SUSPEND_MEM;
<------>}
 
<------>unlock_system_sleep();
}
EXPORT_SYMBOL_GPL(suspend_set_ops);
 
/**
 * suspend_valid_only_mem - Generic memory-only valid callback.
 *
 * Platform drivers that implement mem suspend only and only need to check for
 * that in their .valid() callback can use this instead of rolling their own
 * .valid() callback.
 */
int suspend_valid_only_mem(suspend_state_t state)
{
<------>return state == PM_SUSPEND_MEM;
}
EXPORT_SYMBOL_GPL(suspend_valid_only_mem);
 
static bool sleep_state_supported(suspend_state_t state)
{
<------>return state == PM_SUSPEND_TO_IDLE || (suspend_ops && suspend_ops->enter);
}
 
static int platform_suspend_prepare(suspend_state_t state)
{
<------>return state != PM_SUSPEND_TO_IDLE && suspend_ops->prepare ?
<------><------>suspend_ops->prepare() : 0;
}
 
static int platform_suspend_prepare_late(suspend_state_t state)
{
<------>return state == PM_SUSPEND_TO_IDLE && s2idle_ops && s2idle_ops->prepare ?
<------><------>s2idle_ops->prepare() : 0;
}
 
static int platform_suspend_prepare_noirq(suspend_state_t state)
{
<------>if (state == PM_SUSPEND_TO_IDLE)
<------><------>return s2idle_ops && s2idle_ops->prepare_late ?
<------><------><------>s2idle_ops->prepare_late() : 0;
 
<------>return suspend_ops->prepare_late ? suspend_ops->prepare_late() : 0;
}
 
static void platform_resume_noirq(suspend_state_t state)
{
<------>if (state == PM_SUSPEND_TO_IDLE) {
<------><------>if (s2idle_ops && s2idle_ops->restore_early)
<------><------><------>s2idle_ops->restore_early();
<------>} else if (suspend_ops->wake) {
<------><------>suspend_ops->wake();
<------>}
}
 
static void platform_resume_early(suspend_state_t state)
{
<------>if (state == PM_SUSPEND_TO_IDLE && s2idle_ops && s2idle_ops->restore)
<------><------>s2idle_ops->restore();
}
 
static void platform_resume_finish(suspend_state_t state)
{
<------>if (state != PM_SUSPEND_TO_IDLE && suspend_ops->finish)
<------><------>suspend_ops->finish();
}
 
static int platform_suspend_begin(suspend_state_t state)
{
<------>if (state == PM_SUSPEND_TO_IDLE && s2idle_ops && s2idle_ops->begin)
<------><------>return s2idle_ops->begin();
<------>else if (suspend_ops && suspend_ops->begin)
<------><------>return suspend_ops->begin(state);
<------>else
<------><------>return 0;
}
 
static void platform_resume_end(suspend_state_t state)
{
<------>if (state == PM_SUSPEND_TO_IDLE && s2idle_ops && s2idle_ops->end)
<------><------>s2idle_ops->end();
<------>else if (suspend_ops && suspend_ops->end)
<------><------>suspend_ops->end();
}
 
static void platform_recover(suspend_state_t state)
{
<------>if (state != PM_SUSPEND_TO_IDLE && suspend_ops->recover)
<------><------>suspend_ops->recover();
}
 
static bool platform_suspend_again(suspend_state_t state)
{
<------>return state != PM_SUSPEND_TO_IDLE && suspend_ops->suspend_again ?
<------><------>suspend_ops->suspend_again() : false;
}
 
#ifdef CONFIG_PM_DEBUG
static unsigned int pm_test_delay = 5;
module_param(pm_test_delay, uint, 0644);
MODULE_PARM_DESC(pm_test_delay,
<------><------> "Number of seconds to wait before resuming from suspend test");
#endif
 
static int suspend_test(int level)
{
#ifdef CONFIG_PM_DEBUG
<------>if (pm_test_level == level) {
<------><------>pr_info("suspend debug: Waiting for %d second(s).\n",
<------><------><------><------>pm_test_delay);
<------><------>mdelay(pm_test_delay * 1000);
<------><------>return 1;
<------>}
#endif /* !CONFIG_PM_DEBUG */
<------>return 0;
}
 
/**
 * suspend_prepare - Prepare for entering system sleep state.
 *
 * Common code run for every system sleep state that can be entered (except for
 * hibernation).  Run suspend notifiers, allocate the "suspend" console and
 * freeze processes.
 */
static int suspend_prepare(suspend_state_t state)
{
<------>int error;
 
<------>if (!sleep_state_supported(state))
<------><------>return -EPERM;
 
<------>pm_prepare_console();
 
<------>error = pm_notifier_call_chain_robust(PM_SUSPEND_PREPARE, PM_POST_SUSPEND);
<------>if (error)
<------><------>goto Restore;
 
<------>trace_suspend_resume(TPS("freeze_processes"), 0, true);
<------>error = suspend_freeze_processes();
<------>trace_suspend_resume(TPS("freeze_processes"), 0, false);
<------>if (!error)
<------><------>return 0;
 
<------>log_suspend_abort_reason("One or more tasks refusing to freeze");
<------>suspend_stats.failed_freeze++;
<------>dpm_save_failed_step(SUSPEND_FREEZE);
<------>pm_notifier_call_chain(PM_POST_SUSPEND);
 Restore:
<------>pm_restore_console();
<------>return error;
}
 
/* default implementation */
void __weak arch_suspend_disable_irqs(void)
{
<------>local_irq_disable();
}
 
/* default implementation */
void __weak arch_suspend_enable_irqs(void)
{
<------>local_irq_enable();
}
 
/**
 * suspend_enter - Make the system enter the given sleep state.
 * @state: System sleep state to enter.
 * @wakeup: Returns information that the sleep state should not be re-entered.
 *
 * This function should be called after devices have been suspended.
 */
static int suspend_enter(suspend_state_t state, bool *wakeup)
{
<------>int error, last_dev;
 
<------>error = platform_suspend_prepare(state);
<------>if (error)
<------><------>goto Platform_finish;
 
<------>error = dpm_suspend_late(PMSG_SUSPEND);
<------>if (error) {
<------><------>last_dev = suspend_stats.last_failed_dev + REC_FAILED_NUM - 1;
<------><------>last_dev %= REC_FAILED_NUM;
<------><------>pr_err("late suspend of devices failed\n");
<------><------>log_suspend_abort_reason("late suspend of %s device failed",
<------><------><------><------><------> suspend_stats.failed_devs[last_dev]);
<------><------>goto Platform_finish;
<------>}
<------>error = platform_suspend_prepare_late(state);
<------>if (error)
<------><------>goto Devices_early_resume;
 
<------>error = dpm_suspend_noirq(PMSG_SUSPEND);
<------>if (error) {
<------><------>last_dev = suspend_stats.last_failed_dev + REC_FAILED_NUM - 1;
<------><------>last_dev %= REC_FAILED_NUM;
<------><------>pr_err("noirq suspend of devices failed\n");
<------><------>log_suspend_abort_reason("noirq suspend of %s device failed",
<------><------><------><------><------> suspend_stats.failed_devs[last_dev]);
<------><------>goto Platform_early_resume;
<------>}
<------>error = platform_suspend_prepare_noirq(state);
<------>if (error)
<------><------>goto Platform_wake;
 
<------>if (suspend_test(TEST_PLATFORM))
<------><------>goto Platform_wake;
 
<------>if (state == PM_SUSPEND_TO_IDLE) {
<------><------>s2idle_loop();
<------><------>goto Platform_wake;
<------>}
 
<------>error = suspend_disable_secondary_cpus();
<------>if (error || suspend_test(TEST_CPUS)) {
<------><------>log_suspend_abort_reason("Disabling non-boot cpus failed");
<------><------>goto Enable_cpus;
<------>}
 
<------>arch_suspend_disable_irqs();
<------>BUG_ON(!irqs_disabled());
 
<------>system_state = SYSTEM_SUSPEND;
 
<------>error = syscore_suspend();
<------>if (!error) {
<------><------>*wakeup = pm_wakeup_pending();
<------><------>if (!(suspend_test(TEST_CORE) || *wakeup)) {
<------><------><------>trace_suspend_resume(TPS("machine_suspend"),
<------><------><------><------>state, true);
<------><------><------>error = suspend_ops->enter(state);
<------><------><------>trace_suspend_resume(TPS("machine_suspend"),
<------><------><------><------>state, false);
<------><------>} else if (*wakeup) {
<------><------><------>error = -EBUSY;
<------><------>}
<------><------>syscore_resume();
<------>}
 
<------>system_state = SYSTEM_RUNNING;
 
<------>arch_suspend_enable_irqs();
<------>BUG_ON(irqs_disabled());
 
 Enable_cpus:
<------>suspend_enable_secondary_cpus();
 
 Platform_wake:
<------>platform_resume_noirq(state);
<------>dpm_resume_noirq(PMSG_RESUME);
 
 Platform_early_resume:
<------>platform_resume_early(state);
 
 Devices_early_resume:
<------>dpm_resume_early(PMSG_RESUME);
 
 Platform_finish:
<------>platform_resume_finish(state);
<------>return error;
}
 
/**
 * suspend_devices_and_enter - Suspend devices and enter system sleep state.
 * @state: System sleep state to enter.
 */
int suspend_devices_and_enter(suspend_state_t state)
{
<------>int error;
<------>bool wakeup = false;
 
<------>if (!sleep_state_supported(state))
<------><------>return -ENOSYS;
 
<------>pm_suspend_target_state = state;
 
<------>if (state == PM_SUSPEND_TO_IDLE)
<------><------>pm_set_suspend_no_platform();
 
<------>error = platform_suspend_begin(state);
<------>if (error)
<------><------>goto Close;
 
<------>suspend_console();
<------>suspend_test_start();
<------>error = dpm_suspend_start(PMSG_SUSPEND);
<------>if (error) {
<------><------>pr_err("Some devices failed to suspend, or early wake event detected\n");
<------><------>log_suspend_abort_reason(
<------><------><------><------>"Some devices failed to suspend, or early wake event detected");
<------><------>goto Recover_platform;
<------>}
<------>suspend_test_finish("suspend devices");
<------>if (suspend_test(TEST_DEVICES))
<------><------>goto Recover_platform;
 
<------>do {
<------><------>error = suspend_enter(state, &wakeup);
<------>} while (!error && !wakeup && platform_suspend_again(state));
 
 Resume_devices:
<------>suspend_test_start();
<------>dpm_resume_end(PMSG_RESUME);
<------>suspend_test_finish("resume devices");
<------>trace_suspend_resume(TPS("resume_console"), state, true);
<------>resume_console();
<------>trace_suspend_resume(TPS("resume_console"), state, false);
 
 Close:
<------>platform_resume_end(state);
<------>pm_suspend_target_state = PM_SUSPEND_ON;
<------>return error;
 
 Recover_platform:
<------>platform_recover(state);
<------>goto Resume_devices;
}
 
/**
 * suspend_finish - Clean up before finishing the suspend sequence.
 *
 * Call platform code to clean up, restart processes, and free the console that
 * we've allocated. This routine is not called for hibernation.
 */
static void suspend_finish(void)
{
<------>suspend_thaw_processes();
<------>pm_notifier_call_chain(PM_POST_SUSPEND);
<------>pm_restore_console();
}
 
/**
 * enter_state - Do common work needed to enter system sleep state.
 * @state: System sleep state to enter.
 *
 * Make sure that no one else is trying to put the system into a sleep state.
 * Fail if that's not the case.  Otherwise, prepare for system suspend, make the
 * system enter the given sleep state and clean up after wakeup.
 */
static int enter_state(suspend_state_t state)
{
<------>int error;
 
<------>trace_suspend_resume(TPS("suspend_enter"), state, true);
<------>if (state == PM_SUSPEND_TO_IDLE) {
#ifdef CONFIG_PM_DEBUG
<------><------>if (pm_test_level != TEST_NONE && pm_test_level <= TEST_CPUS) {
<------><------><------>pr_warn("Unsupported test mode for suspend to idle, please choose none/freezer/devices/platform.\n");
<------><------><------>return -EAGAIN;
<------><------>}
#endif
<------>} else if (!valid_state(state)) {
<------><------>return -EINVAL;
<------>}
<------>if (!mutex_trylock(&system_transition_mutex))
<------><------>return -EBUSY;
 
<------>if (state == PM_SUSPEND_TO_IDLE)
<------><------>s2idle_begin();
 
<------>if (sync_on_suspend_enabled) {
<------><------>trace_suspend_resume(TPS("sync_filesystems"), 0, true);
<------><------>ksys_sync_helper();
<------><------>trace_suspend_resume(TPS("sync_filesystems"), 0, false);
<------>}
 
<------>pm_pr_dbg("Preparing system for sleep (%s)\n", mem_sleep_labels[state]);
<------>pm_suspend_clear_flags();
<------>error = suspend_prepare(state);
<------>if (error)
<------><------>goto Unlock;
 
<------>if (suspend_test(TEST_FREEZER))
<------><------>goto Finish;
 
<------>trace_suspend_resume(TPS("suspend_enter"), state, false);
<------>pm_pr_dbg("Suspending system (%s)\n", mem_sleep_labels[state]);
<------>pm_restrict_gfp_mask();
<------>error = suspend_devices_and_enter(state);
<------>pm_restore_gfp_mask();
 
 Finish:
<------>events_check_enabled = false;
<------>pm_pr_dbg("Finishing wakeup.\n");
<------>suspend_finish();
 Unlock:
<------>mutex_unlock(&system_transition_mutex);
<------>return error;
}
 
/**
 * pm_suspend - Externally visible function for suspending the system.
 * @state: System sleep state to enter.
 *
 * Check if the value of @state represents one of the supported states,
 * execute enter_state() and update system suspend statistics.
 */
int pm_suspend(suspend_state_t state)
{
<------>int error;
 
<------>if (state <= PM_SUSPEND_ON || state >= PM_SUSPEND_MAX)
<------><------>return -EINVAL;
 
<------>pr_info("suspend entry (%s)\n", mem_sleep_labels[state]);
<------>error = enter_state(state);
<------>if (error) {
<------><------>suspend_stats.fail++;
<------><------>dpm_save_failed_errno(error);
<------>} else {
<------><------>suspend_stats.success++;
<------>}
<------>pr_info("suspend exit\n");
<------>return error;
}
EXPORT_SYMBOL(pm_suspend);