1 /** 2 * \file 3 * 4 * \brief Critical sections related functionality declaration. 5 * 6 * Copyright (C) 2014 Atmel Corporation. All rights reserved. 7 * 8 * \asf_license_start 9 * 10 * \page License 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions are met: 14 * 15 * 1. Redistributions of source code must retain the above copyright notice, 16 * this list of conditions and the following disclaimer. 17 * 18 * 2. Redistributions in binary form must reproduce the above copyright notice, 19 * this list of conditions and the following disclaimer in the documentation 20 * and/or other materials provided with the distribution. 21 * 22 * 3. The name of Atmel may not be used to endorse or promote products derived 23 * from this software without specific prior written permission. 24 * 25 * 4. This software may only be redistributed and used in connection with an 26 * Atmel microcontroller product. 27 * 28 * THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR IMPLIED 29 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 30 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE 31 * EXPRESSLY AND SPECIFICALLY DISCLAIMED. IN NO EVENT SHALL ATMEL BE LIABLE FOR 32 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 33 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 34 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 35 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 36 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN 37 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 38 * POSSIBILITY OF SUCH DAMAGE. 39 * 40 * \asf_license_stop 41 * 42 */ 43 44 #ifndef _HAL_ATOMIC_H_INCLUDED 45 #define _HAL_ATOMIC_H_INCLUDED 46 47 #include <compiler.h> 48 49 #ifdef __cplusplus 50 extern "C" { 51 #endif 52 53 /** 54 * \addtogroup doc_driver_hal_helper_atomic 55 * 56 *@{ 57 */ 58 59 /** 60 * \brief Type for the register holding global interrupt enable flag 61 */ 62 typedef uint32_t hal_atomic_t; 63 64 /** 65 * \brief Helper macro for entering critical sections 66 * 67 * This macro is recommended to be used instead of a direct call 68 * hal_enterCritical() function to enter critical 69 * sections. No semicolon is required after the macro. 70 * 71 * \section atomic_usage Usage Example 72 * \code 73 * CRITICAL_SECTION_ENTER() 74 * Critical code 75 * CRITICAL_SECTION_LEAVE() 76 * \endcode 77 */ 78 #define CRITICAL_SECTION_ENTER() \ 79 { \ 80 volatile hal_atomic_t __atomic; \ 81 atomic_enter_critical(&__atomic); 82 83 /** 84 * \brief Helper macro for leaving critical sections 85 * 86 * This macro is recommended to be used instead of a direct call 87 * hal_leaveCritical() function to leave critical 88 * sections. No semicolon is required after the macro. 89 * 90 * \section atomic_usage Usage Example 91 * \code 92 * CRITICAL_SECTION_ENTER() 93 * Some critical code 94 * CRITICAL_SECTION_LEAVE() 95 * \endcode 96 */ 97 #define CRITICAL_SECTION_LEAVE() \ 98 atomic_leave_critical(&__atomic); \ 99 } 100 101 /** 102 * \brief Disable interrupts, enter critical section 103 * 104 * Disables global interrupts. Supports nested critical sections, 105 * so that global interrupts are only re-enabled 106 * upon leaving the outermost nested critical section. 107 * 108 * \param[out] atomic The pointer to a variable to store the value of global 109 * interrupt enable flag 110 */ 111 void atomic_enter_critical(hal_atomic_t volatile *atomic); 112 113 /** 114 * \brief Exit atomic section 115 * 116 * Enables global interrupts. Supports nested critical sections, 117 * so that global interrupts are only re-enabled 118 * upon leaving the outermost nested critical section. 119 * 120 * \param[in] atomic The pointer to a variable, which stores the latest stored 121 * value of the global interrupt enable flag 122 */ 123 void atomic_leave_critical(hal_atomic_t volatile *atomic); 124 125 /** 126 * \brief Retrieve the current driver version 127 * 128 * \return Current driver version. 129 */ 130 uint32_t atomic_get_version(void); 131 /**@}*/ 132 133 #ifdef __cplusplus 134 } 135 #endif 136 137 #endif /* _HAL_ATOMIC_H_INCLUDED */ 138
