| 0,0 → 1,128 |
|---|
| /* |
| * Copyright (c) 2007 Michal Kebrt |
| * All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * |
| * - Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * - 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. |
| * - The name of the author may not be used to endorse or promote products |
| * derived from this software without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
| * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
| * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
| * IN NO EVENT SHALL THE AUTHOR 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. |
| */ |
| |
| /** @addtogroup arm32 |
| * @{ |
| */ |
| /** @file |
| * @brief Atomic operations. |
| */ |
| |
| #ifndef KERN_arm32_ATOMIC_H_ |
| #define KERN_arm32_ATOMIC_H_ |
| |
| /** Atomic addition. |
| * |
| * @param val Where to add. |
| * @param i Value to be added. |
| * |
| * @return Value after addition. |
| */ |
| static inline long atomic_add(atomic_t *val, int i) |
| { |
| int ret; |
| volatile long *mem = &(val->count); |
| |
| asm volatile ( |
| "1:\n" |
| "ldr r2, [%1] \n" |
| "add r3, r2, %2 \n" |
| "str r3, %0 \n" |
| "swp r3, r3, [%1] \n" |
| "cmp r3, r2 \n" |
| "bne 1b \n" |
| |
| : "=m" (ret) |
| : "r" (mem), "r" (i) |
| : "r3", "r2" |
| ); |
| |
| return ret; |
| } |
| |
| /** Atomic increment. |
| * |
| * @param val Variable to be incremented. |
| */ |
| static inline void atomic_inc(atomic_t *val) |
| { |
| atomic_add(val, 1); |
| } |
| |
| /** Atomic decrement. |
| * |
| * @param val Variable to be decremented. |
| */ |
| static inline void atomic_dec(atomic_t *val) { |
| atomic_add(val, -1); |
| } |
| |
| /** Atomic pre-increment. |
| * |
| * @param val Variable to be incremented. |
| * @return Value after incrementation. |
| */ |
| static inline long atomic_preinc(atomic_t *val) |
| { |
| return atomic_add(val, 1); |
| } |
| |
| /** Atomic pre-decrement. |
| * |
| * @param val Variable to be decremented. |
| * @return Value after decrementation. |
| */ |
| static inline long atomic_predec(atomic_t *val) |
| { |
| return atomic_add(val, -1); |
| } |
| |
| /** Atomic post-increment. |
| * |
| * @param val Variable to be incremented. |
| * @return Value before incrementation. |
| */ |
| static inline long atomic_postinc(atomic_t *val) |
| { |
| return atomic_add(val, 1) - 1; |
| } |
| |
| /** Atomic post-decrement. |
| * |
| * @param val Variable to be decremented. |
| * @return Value before decrementation. |
| */ |
| static inline long atomic_postdec(atomic_t *val) |
| { |
| return atomic_add(val, -1) + 1; |
| } |
| |
| #endif |
| |
| /** @} |
| */ |