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Diffstat (limited to 'FreeRTOS/Demo/AVR_ATmega328PB_Xplained_mini_GCC/RTOSDemo/utils/atomic.h')
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diff --git a/FreeRTOS/Demo/AVR_ATmega328PB_Xplained_mini_GCC/RTOSDemo/utils/atomic.h b/FreeRTOS/Demo/AVR_ATmega328PB_Xplained_mini_GCC/RTOSDemo/utils/atomic.h new file mode 100644 index 000000000..f6002f1be --- /dev/null +++ b/FreeRTOS/Demo/AVR_ATmega328PB_Xplained_mini_GCC/RTOSDemo/utils/atomic.h @@ -0,0 +1,125 @@ +/** + * \file atomic.h + * + * \brief Macros used for atomic memory access. + * + * + * Copyright (C) 2016 Atmel Corporation. All rights reserved. + * + * \asf_license_start + * + * \page License + * + * 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. The name of Atmel may not be used to endorse or promote products derived + * from this software without specific prior written permission. + * + * 4. This software may only be redistributed and used in connection with an + * Atmel microcontroller product. + * + * THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR IMPLIED + * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE + * EXPRESSLY AND SPECIFICALLY DISCLAIMED. IN NO EVENT SHALL ATMEL 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. + * + * \asf_license_stop + * + * + */ + +#ifndef ATOMIC_H +#define ATOMIC_H + +/** + * \defgroup doc_driver_utils_atomic Atomic memory access and critical sections + * \ingroup doc_driver_utils + * + * Atomic memory access and critical sections + * + * \{ + */ + +/* clang-format off */ + +#if defined(__GNUC__) || defined (__DOXYGEN__) + +/** + * \brief Enter a critical region + * + * Saves the contents of the status register, including the Global + * Interrupt Enable bit, so that it can be restored upon leaving the + * critical region. Thereafter, clears the Global Interrupt Enable Bit. + * This macro takes a parameter P that is unused for the GCC compiler, + * but necessary for code compatibility with the IAR compiler. The IAR + * compiler declares a variable with the name of the parameter for + * holding the SREG value. Since a variable is declared in the macro, + * this variable must have a name that is unique within the scope + * that the critical region is declared within, otherwise compilation + * will fail. + * + * \param[in] UNUSED(GCC)/P(IAR) Name of variable storing SREG + * + */ + +#define ENTER_CRITICAL(UNUSED) __asm__ __volatile__ ( \ + "in __tmp_reg__, __SREG__" "\n\t" \ + "cli" "\n\t" \ + "push __tmp_reg__" "\n\t" \ + ::: "memory" \ + ) + +/** + * \brief Exit a critical region + * + * Restores the contents of the status register, including the Global + * Interrupt Enable bit, as it was when entering the critical region. + * This macro takes a parameter P that is unused for the GCC compiler, + * but necessary for code compatibility with the IAR compiler. The IAR + * compiler uses this parameter as the name of a variable that holds + * the SREG value. The parameter must be identical to the parameter + * used in the corresponding ENTER_CRITICAL(). + * + * \param[in] UNUSED(GCC)/P(IAR) Name of variable storing SREG + * + */ + +#define EXIT_CRITICAL(UNUSED) __asm__ __volatile__ ( \ + "pop __tmp_reg__" "\n\t" \ + "out __SREG__, __tmp_reg__" "\n\t" \ + ::: "memory" \ + ) + +#define DISABLE_INTERRUPTS() __asm__ __volatile__ ( "cli" ::: "memory") +#define ENABLE_INTERRUPTS() __asm__ __volatile__ ( "sei" ::: "memory") + +#elif defined(__ICCAVR__) + +#define ENTER_CRITICAL(P) unsigned char P = __save_interrupt();__disable_interrupt(); +#define EXIT_CRITICAL(P) __restore_interrupt(P); + +#define DISABLE_INTERRUPTS() __disable_interrupt(); +#define ENABLE_INTERRUPTS() __enable_interrupt(); + +#else +# error Unsupported compiler. +#endif + +/* clang-format on */ + +#endif /* ATOMIC_H */ |