Rev 2479 | Details | Compare with Previous | Last modification | View Log | RSS feed
| Rev | Author | Line No. | Line |
|---|---|---|---|
| 2128 | jermar | 1 | /* |
| 2465 | jermar | 2 | * Copyright (c) 2007 Michal Kebrt |
| 2128 | jermar | 3 | * All rights reserved. |
| 4 | * |
||
| 5 | * Redistribution and use in source and binary forms, with or without |
||
| 6 | * modification, are permitted provided that the following conditions |
||
| 7 | * are met: |
||
| 8 | * |
||
| 9 | * - Redistributions of source code must retain the above copyright |
||
| 10 | * notice, this list of conditions and the following disclaimer. |
||
| 11 | * - Redistributions in binary form must reproduce the above copyright |
||
| 12 | * notice, this list of conditions and the following disclaimer in the |
||
| 13 | * documentation and/or other materials provided with the distribution. |
||
| 14 | * - The name of the author may not be used to endorse or promote products |
||
| 15 | * derived from this software without specific prior written permission. |
||
| 16 | * |
||
| 17 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
||
| 18 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
||
| 19 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
||
| 20 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
||
| 21 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
||
| 22 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
||
| 23 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
||
| 24 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
||
| 25 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
||
| 26 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
||
| 27 | */ |
||
| 28 | |||
| 29 | /** @addtogroup libcarm32 |
||
| 30 | * @{ |
||
| 31 | */ |
||
| 32 | /** @file |
||
| 2465 | jermar | 33 | * @brief Atomic operations. |
| 2128 | jermar | 34 | */ |
| 35 | |||
| 36 | #ifndef LIBC_arm32_ATOMIC_H_ |
||
| 37 | #define LIBC_arm32_ATOMIC_H_ |
||
| 38 | |||
| 39 | /** Atomic addition. |
||
| 40 | * |
||
| 2465 | jermar | 41 | * @param val Where to add. |
| 42 | * @param i Value to be added. |
||
| 2128 | jermar | 43 | * |
| 44 | * @return Value after addition. |
||
| 45 | */ |
||
| 2465 | jermar | 46 | static inline long atomic_add(atomic_t *val, int i) |
| 2128 | jermar | 47 | { |
| 2465 | jermar | 48 | int ret; |
| 49 | volatile long * mem = &(val->count); |
||
| 50 | |||
| 51 | asm volatile ( |
||
| 2468 | jermar | 52 | "1:\n" |
| 53 | "ldr r2, [%1]\n" |
||
| 54 | "add r3, r2, %2\n" |
||
| 55 | "str r3, %0\n" |
||
| 56 | "swp r3, r3, [%1]\n" |
||
| 57 | "cmp r3, r2\n" |
||
| 58 | "bne 1b\n" |
||
| 2465 | jermar | 59 | |
| 60 | : "=m" (ret) |
||
| 61 | : "r" (mem), "r" (i) |
||
| 62 | : "r3", "r2" |
||
| 63 | ); |
||
| 64 | |||
| 65 | return ret; |
||
| 2128 | jermar | 66 | } |
| 67 | |||
| 2465 | jermar | 68 | |
| 69 | /** Atomic increment. |
||
| 70 | * |
||
| 71 | * @param val Variable to be incremented. |
||
| 72 | */ |
||
| 2468 | jermar | 73 | static inline void atomic_inc(atomic_t *val) |
| 74 | { |
||
| 75 | atomic_add(val, 1); |
||
| 76 | } |
||
| 2465 | jermar | 77 | |
| 78 | |||
| 79 | /** Atomic decrement. |
||
| 80 | * |
||
| 81 | * @param val Variable to be decremented. |
||
| 82 | */ |
||
| 2468 | jermar | 83 | static inline void atomic_dec(atomic_t *val) |
| 84 | { |
||
| 85 | atomic_add(val, -1); |
||
| 86 | } |
||
| 2128 | jermar | 87 | |
| 88 | |||
| 2465 | jermar | 89 | /** Atomic pre-increment. |
| 90 | * |
||
| 91 | * @param val Variable to be incremented. |
||
| 92 | * @return Value after incrementation. |
||
| 93 | */ |
||
| 2468 | jermar | 94 | static inline long atomic_preinc(atomic_t *val) |
| 95 | { |
||
| 96 | return atomic_add(val, 1); |
||
| 97 | } |
||
| 2128 | jermar | 98 | |
| 2465 | jermar | 99 | |
| 100 | /** Atomic pre-decrement. |
||
| 101 | * |
||
| 102 | * @param val Variable to be decremented. |
||
| 103 | * @return Value after decrementation. |
||
| 104 | */ |
||
| 2468 | jermar | 105 | static inline long atomic_predec(atomic_t *val) |
| 106 | { |
||
| 107 | return atomic_add(val, -1); |
||
| 108 | } |
||
| 2465 | jermar | 109 | |
| 110 | |||
| 111 | /** Atomic post-increment. |
||
| 112 | * |
||
| 113 | * @param val Variable to be incremented. |
||
| 114 | * @return Value before incrementation. |
||
| 115 | */ |
||
| 2468 | jermar | 116 | static inline long atomic_postinc(atomic_t *val) |
| 117 | { |
||
| 118 | return atomic_add(val, 1) - 1; |
||
| 119 | } |
||
| 2465 | jermar | 120 | |
| 121 | |||
| 122 | /** Atomic post-decrement. |
||
| 123 | * |
||
| 124 | * @param val Variable to be decremented. |
||
| 125 | * @return Value before decrementation. |
||
| 126 | */ |
||
| 2468 | jermar | 127 | static inline long atomic_postdec(atomic_t *val) |
| 128 | { |
||
| 129 | return atomic_add(val, -1) + 1; |
||
| 130 | } |
||
| 2465 | jermar | 131 | |
| 132 | |||
| 2128 | jermar | 133 | #endif |
| 134 | |||
| 135 | /** @} |
||
| 136 | */ |