| Jens Wiklander | ac27ec1 | 2015-07-15 15:23:14 +0200 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright (c) 2015, Linaro Limited |
| 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 are met: |
| 7 | * |
| 8 | * 1. Redistributions of source code must retain the above copyright notice, |
| 9 | * this list of conditions and the following disclaimer. |
| 10 | * |
| 11 | * 2. Redistributions in binary form must reproduce the above copyright notice, |
| 12 | * this list of conditions and the following disclaimer in the documentation |
| 13 | * and/or other materials provided with the distribution. |
| 14 | * |
| 15 | * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" |
| 16 | * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| 17 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| 18 | * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE |
| 19 | * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
| 20 | * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
| 21 | * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
| 22 | * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
| 23 | * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
| 24 | * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
| 25 | * POSSIBILITY OF SUCH DAMAGE. |
| 26 | */ |
| 27 | |
| 28 | /* uint32_t atomic_inc(uint32_t *v); */ |
| 29 | .global atomic_inc |
| 30 | .func atomic_inc |
| 31 | atomic_inc: |
| 32 | ldrex r1, [r0] |
| 33 | add r1, r1, #1 |
| 34 | strex r2, r1, [r0] |
| 35 | cmp r2, #0 |
| 36 | bne atomic_inc |
| 37 | mov r0, r1 |
| 38 | bx lr |
| 39 | .endfunc |
| 40 | |
| 41 | /* uint32_t atomic_dec(uint32_t *v); */ |
| 42 | .global atomic_dec |
| 43 | .func atomic_dec |
| 44 | atomic_dec: |
| 45 | ldrex r1, [r0] |
| 46 | sub r1, r1, #1 |
| 47 | strex r2, r1, [r0] |
| 48 | cmp r2, #0 |
| 49 | bne atomic_dec |
| 50 | mov r0, r1 |
| 51 | bx lr |
| 52 | .endfunc |