1 /* 2 * Copyright (C) 2016 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #ifndef _ATOMIC_H_ 18 #define _ATOMIC_H_ 19 20 #ifdef __cplusplus 21 extern "C" { 22 #endif 23 24 #include <stdint.h> 25 #include <stdbool.h> 26 #include <cpu/inc/atomic.h> 27 #include <cpu/inc/barrier.h> 28 29 /* almost all platforms support byte and 32-bit operations of this sort. please do not add other sizes here */ 30 uint32_t atomicXchgByte(volatile uint8_t *byte, uint32_t newVal); 31 uint32_t atomicXchg32bits(volatile uint32_t *word, uint32_t newVal); 32 bool atomicCmpXchgByte(volatile uint8_t *byte, uint32_t prevVal, uint32_t newVal); 33 bool atomicCmpXchg32bits(volatile uint32_t *word, uint32_t prevVal, uint32_t newVal); 34 35 //returns old value 36 uint32_t atomicAddByte(volatile uint8_t *byte, uint32_t addend); 37 uint32_t atomicAdd32bits(volatile uint32_t *word, uint32_t addend); 38 39 //writes with barriers 40 static inline uint32_t atomicReadByte(volatile uint8_t *byte) 41 { 42 mem_reorder_barrier(); 43 return *byte; 44 } 45 46 static inline uint32_t atomicRead32bits(volatile uint32_t *word) 47 { 48 mem_reorder_barrier(); 49 return *word; 50 } 51 52 static inline void atomicWriteByte(volatile uint8_t *byte, uint32_t val) 53 { 54 *byte = val; 55 mem_reorder_barrier(); 56 } 57 58 static inline void atomicWrite32bits(volatile uint32_t *word, uint32_t val) 59 { 60 *word = val; 61 mem_reorder_barrier(); 62 } 63 64 #ifdef __cplusplus 65 } 66 #endif 67 68 #endif 69
