1*7e321ac1Sguenther /* $OpenBSD: _atomic_lock.c,v 1.1 2017/08/15 06:13:24 guenther Exp $ */
2*7e321ac1Sguenther
3*7e321ac1Sguenther /*
4*7e321ac1Sguenther * Copyright (c) 2003, Miodrag Vallat.
5*7e321ac1Sguenther *
6*7e321ac1Sguenther * Redistribution and use in source and binary forms, with or without
7*7e321ac1Sguenther * modification, are permitted provided that the following conditions
8*7e321ac1Sguenther * are met:
9*7e321ac1Sguenther * 1. Redistributions of source code must retain the above copyright
10*7e321ac1Sguenther * notice, this list of conditions and the following disclaimer.
11*7e321ac1Sguenther * 2. Redistributions in binary form must reproduce the above copyright
12*7e321ac1Sguenther * notice, this list of conditions and the following disclaimer in the
13*7e321ac1Sguenther * documentation and/or other materials provided with the distribution.
14*7e321ac1Sguenther *
15*7e321ac1Sguenther * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16*7e321ac1Sguenther * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
17*7e321ac1Sguenther * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
18*7e321ac1Sguenther * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
19*7e321ac1Sguenther * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
20*7e321ac1Sguenther * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
21*7e321ac1Sguenther * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22*7e321ac1Sguenther * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
23*7e321ac1Sguenther * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
24*7e321ac1Sguenther * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
25*7e321ac1Sguenther * POSSIBILITY OF SUCH DAMAGE.
26*7e321ac1Sguenther */
27*7e321ac1Sguenther
28*7e321ac1Sguenther /*
29*7e321ac1Sguenther * Atomic lock for m88k
30*7e321ac1Sguenther */
31*7e321ac1Sguenther
32*7e321ac1Sguenther #include <machine/spinlock.h>
33*7e321ac1Sguenther
34*7e321ac1Sguenther int
_atomic_lock(volatile _atomic_lock_t * lock)35*7e321ac1Sguenther _atomic_lock(volatile _atomic_lock_t *lock)
36*7e321ac1Sguenther {
37*7e321ac1Sguenther _atomic_lock_t old;
38*7e321ac1Sguenther
39*7e321ac1Sguenther old = _ATOMIC_LOCK_LOCKED;
40*7e321ac1Sguenther __asm__ volatile
41*7e321ac1Sguenther ("xmem %0, %2, %%r0" : "=r" (old) : "0" (old), "r" (lock));
42*7e321ac1Sguenther
43*7e321ac1Sguenther return (old != _ATOMIC_LOCK_UNLOCKED);
44*7e321ac1Sguenther }
45