1 /* 2 * Copyright (c) 2024 Raspberry Pi (Trading) Ltd. 3 * Copyright (c) 2024 Stephen Street (stephen@redrocketcomputing.com). 4 * 5 * SPDX-License-Identifier: BSD-3-Clause 6 */ 7 8 #ifndef __STDATOMIC_H 9 #define __STDATOMIC_H 10 11 #ifdef __cplusplus 12 extern "C" { 13 #endif 14 15 /** \file stdatomic.h 16 * \defgroup pico_atomic pico_atomic 17 * 18 * \brief Helper implementations for C11 atomics 19 * 20 * \if rp2040_specific 21 * On RP2040 a spin lock is used as protection for all atomic operations, since there is no C library support. 22 * \endif 23 * 24 * \if rp2350_specific 25 * On RP2350 the C-library provides implementations for all 1-byte, 2-byte and 4-byte atomics using processor 26 * exclusive operations. This library provides a spin-lock protected version for arbitrary-sized atomics (including 64-bit). 27 * \endif 28 */ 29 #include <stdint.h> 30 #include_next <stdatomic.h> 31 32 // needed for PICO_C_COMPILER_IS_GNU 33 #include "pico.h" 34 35 #if PICO_RP2040 && PICO_C_COMPILER_IS_GNU 36 // on GNU without exclusive instructions these don't get routed thru _1 functions for some reason 37 #undef atomic_flag_test_and_set 38 #undef atomic_flag_test_and_set_explicit 39 40 extern _Bool __atomic_test_and_set_c(volatile void *mem, int model); 41 42 #define atomic_flag_test_and_set(PTR) __atomic_test_and_set_c((PTR), __ATOMIC_SEQ_CST) 43 #define atomic_flag_test_and_set_explicit(PTR, MO) __atomic_test_and_set_c((PTR), (MO)) 44 #endif 45 46 #ifdef __cplusplus 47 } 48 #endif 49 #endif 50
