/**************************************************************************** * arch/arm/src/xmc4/xmc4_idle.c * * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. The * ASF licenses this file to you under the Apache License, Version 2.0 (the * "License"); you may not use this file except in compliance with the * License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the * License for the specific language governing permissions and limitations * under the License. * ****************************************************************************/ /**************************************************************************** * Included Files ****************************************************************************/ #include #include #include #include #include "arm_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_autoled_on(LED_IDLE) # define END_IDLE() board_autoled_off(LED_IDLE) #else # define BEGIN_IDLE() # define END_IDLE() #endif /**************************************************************************** * Private Data ****************************************************************************/ /**************************************************************************** * Private Functions ****************************************************************************/ /**************************************************************************** * Public Functions ****************************************************************************/ /**************************************************************************** * Name: up_idle * * Description: * up_idle() is the logic that will be executed when there 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. */ nxsched_process_timer(); #else /* Sleep until an interrupt occurs to save power */ BEGIN_IDLE(); asm("WFI"); END_IDLE(); #endif }