/****************************************************************************
* arch/arm/src/kl/kl_idle.c
*
* Copyright (C) 2013, 2015 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <arch/board/board.h>
#include <nuttx/config.h>
#include <nuttx/arch.h>
#include <nuttx/board.h>
#include <nuttx/power/pm.h>
#include <arch/irq.h>
#include "chip.h"
#include "up_internal.h"
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/* Does the board support an IDLE LED to indicate that the board is in the
* IDLE state?
*/
#if defined(CONFIG_ARCH_LEDS) && defined(LED_IDLE)
# define BEGIN_IDLE() board_led_on(LED_IDLE)
# define END_IDLE() board_led_off(LED_IDLE)
#else
# define BEGIN_IDLE()
# define END_IDLE()
#endif
/****************************************************************************
* Private Data
****************************************************************************/
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: up_idlepm
*
* Description:
* Perform IDLE state power management.
*
****************************************************************************/
#ifdef CONFIG_PM
static void up_idlepm(void)
{
static enum pm_state_e oldstate = PM_NORMAL;
enum pm_state_e newstate;
irqstate_t flags;
int ret;
/* Decide, which power saving level can be obtained */
newstate = pm_checkstate();
/* Check for state changes */
if (newstate != oldstate)
{
flags = irqsave();
/* Perform board-specific, state-dependent logic here */
llvdbg("newstate= %d oldstate=%d\n", newstate, oldstate);
/* Then force the global state change */
ret = pm_changestate(newstate);
if (ret < 0)
{
/* The new state change failed, revert to the preceding state */
(void)pm_changestate(oldstate);
}
else
{
/* Save the new state */
oldstate = newstate;
}
/* MCU-specific power management logic */
switch (newstate)
{
case PM_NORMAL:
break;
case PM_IDLE:
break;
case PM_STANDBY:
kl_pmstop(true);
break;
case PM_SLEEP:
(void)kl_pmstandby();
break;
default:
break;
}
irqrestore(flags);
}
}
#else
# define up_idlepm()
#endif
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: up_idle
*
* Description:
* up_idle() is the logic that will be executed when their is no other
* ready-to-run task. This is processor idle time and will continue until
* some interrupt occurs to cause a context switch from the idle task.
*
* Processing in this state may be processor-specific. e.g., this is where
* power management operations might be performed.
*
****************************************************************************/
void up_idle(void)
{
#if defined(CONFIG_SUPPRESS_INTERRUPTS) || defined(CONFIG_SUPPRESS_TIMER_INTS)
/* If the system is idle and there are no timer interrupts, then process
* "fake" timer interrupts. Hopefully, something will wake up.
*/
sched_process_timer();
#else
/* Perform IDLE mode power management */
up_idlepm();
/* Sleep until an interrupt occurs to save power. */
BEGIN_IDLE();
asm("WFI");
END_IDLE();
#endif
}
