PM电源管理 PM组件

启用PM(1.0)组件后，睡眠进不去，一直在IDLE线程中循环

发布于 2021-10-15 15:19:06 浏览：1425 订阅该版

张世争 2021-10-15

学以致用

fanfan 2021-10-19

这家伙很懒，什么也没写！

```
void rt_pm_enter(void)
{
    rt_ubase_t level;
    struct rt_pm *pm;
    rt_uint32_t index;
    rt_tick_t timeout_tick;

pm = &_pm;

/* disable interrupt before check run modes */
    level = rt_hw_interrupt_disable();
    /* check each run mode, and decide to swithc to run mode or sleep mode */
    for (index = 0; index < PM_RUN_MODE_COUNT; index++)
    {
        if (pm->modes[index])
        {
            if (index > pm->current_mode)
            {
                pm->ops->exit(pm);
                pm->current_mode = index;
                pm->ops->enter(pm);
#if PM_RUN_MODE_COUNT > 1
                pm->ops->frequency_change(pm, 0);
                _pm_device_frequency_change();
#endif
            }

rt_hw_interrupt_enable(level);
            /* The current mode is run mode, no need to check sleep mode */
            return ;
        }
    }
    /* enable interrupt after check run modes */
    rt_hw_interrupt_enable(level);

level = rt_hw_interrupt_disable();
    /* check each sleep mode to decide which mode can system sleep. */
    for (index = PM_SLEEP_MODE_START; index < PM_SLEEP_MODE_START + PM_SLEEP_MODE_COUNT; index++)
    {
        if (pm->modes[index])
        {
            /* let mcu sleep when system is idle */

/* run mode to sleep mode */
            if (pm->current_mode < PM_SLEEP_MODE_START)
            {
                /* exit run mode */
                pm->ops->exit(pm);
            }

/* set current power mode */
            pm->current_mode = index;
            pm->exit_count = 1;

/* suspend all of devices with PM feature */
            _pm_device_suspend();

/* should start pm timer */
            if (pm->timer_mask & (1 << index))
            {
                /* get next os tick */
                timeout_tick = rt_timer_next_timeout_tick();
                if (timeout_tick != RT_TICK_MAX)
                {
                    timeout_tick -= rt_tick_get();

#if defined(PM_MIN_ENTER_SLEEP_TICK) && PM_MIN_ENTER_SLEEP_TICK > 0
                    if (timeout_tick < PM_MIN_ENTER_SLEEP_TICK)
                    {
                        rt_hw_interrupt_enable(level);
                        /* limit the minimum time to enter timer sleep mode */
                        return ;
                    }
#endif
                }
                /* startup pm timer */
                pm->ops->timer_start(pm, timeout_tick);
            }

/* enter sleep and wait to be waken up */
            pm->ops->enter(pm);

/* exit from low power mode */
            rt_pm_exit();

rt_hw_interrupt_enable(level);
            return ;
        }
    }

rt_hw_interrupt_enable(level);
}
```
在这个函数中，为什么在操作之前要先关全局中断呢？
华大的单片机，关闭全局中断后，进入睡眠的指令不起作用，所以会在IDLE线程中循环run和sleep两种状态