diff options
Diffstat (limited to 'nuttx/arch/arm/src/stm32/stm32_idle.c')
-rw-r--r-- | nuttx/arch/arm/src/stm32/stm32_idle.c | 188 |
1 files changed, 188 insertions, 0 deletions
diff --git a/nuttx/arch/arm/src/stm32/stm32_idle.c b/nuttx/arch/arm/src/stm32/stm32_idle.c new file mode 100644 index 000000000..791a79429 --- /dev/null +++ b/nuttx/arch/arm/src/stm32/stm32_idle.c @@ -0,0 +1,188 @@ +/**************************************************************************** + * arch/arm/src/stm32/stm32_idle.c + * + * Copyright (C) 2011-2012 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/power/pm.h> + +#include <arch/irq.h> + +#include "stm32_pm.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() up_ledon(LED_IDLE) +# define END_IDLE() up_ledoff(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: + stm32_pmstop(true); + break; + + case PM_SLEEP: + (void)stm32_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 +} + |