xref: /optee_os/lib/libutils/ext/arch/arm/atomic_a64.S (revision e17dd72a48dc39765da65a7e1b6b547d7be11412)
1*e17dd72aSJens Wiklander/*
2*e17dd72aSJens Wiklander * Copyright (c) 2015-2016, Linaro Limited
3*e17dd72aSJens Wiklander * All rights reserved.
4*e17dd72aSJens Wiklander *
5*e17dd72aSJens Wiklander * Redistribution and use in source and binary forms, with or without
6*e17dd72aSJens Wiklander * modification, are permitted provided that the following conditions are met:
7*e17dd72aSJens Wiklander *
8*e17dd72aSJens Wiklander * 1. Redistributions of source code must retain the above copyright notice,
9*e17dd72aSJens Wiklander * this list of conditions and the following disclaimer.
10*e17dd72aSJens Wiklander *
11*e17dd72aSJens Wiklander * 2. Redistributions in binary form must reproduce the above copyright notice,
12*e17dd72aSJens Wiklander * this list of conditions and the following disclaimer in the documentation
13*e17dd72aSJens Wiklander * and/or other materials provided with the distribution.
14*e17dd72aSJens Wiklander *
15*e17dd72aSJens Wiklander * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
16*e17dd72aSJens Wiklander * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17*e17dd72aSJens Wiklander * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18*e17dd72aSJens Wiklander * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
19*e17dd72aSJens Wiklander * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
20*e17dd72aSJens Wiklander * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
21*e17dd72aSJens Wiklander * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
22*e17dd72aSJens Wiklander * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
23*e17dd72aSJens Wiklander * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
24*e17dd72aSJens Wiklander * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
25*e17dd72aSJens Wiklander * POSSIBILITY OF SUCH DAMAGE.
26*e17dd72aSJens Wiklander */
27*e17dd72aSJens Wiklander
28*e17dd72aSJens Wiklander#include <asm.S>
29*e17dd72aSJens Wiklander
30*e17dd72aSJens Wiklander
31*e17dd72aSJens Wiklander/* uint32_t atomic_inc32(uint32_t *v); */
32*e17dd72aSJens WiklanderFUNC atomic_inc32 , :
33*e17dd72aSJens Wiklander	ldaxr	w1, [x0]
34*e17dd72aSJens Wiklander	add	w1, w1, #1
35*e17dd72aSJens Wiklander	stxr	w2, w1, [x0]
36*e17dd72aSJens Wiklander	cmp	w2, #0
37*e17dd72aSJens Wiklander	bne	atomic_inc32
38*e17dd72aSJens Wiklander	mov	w0, w1
39*e17dd72aSJens Wiklander	ret
40*e17dd72aSJens WiklanderEND_FUNC atomic_inc32
41*e17dd72aSJens Wiklander
42*e17dd72aSJens Wiklander/* uint32_t atomic_dec32(uint32_t *v); */
43*e17dd72aSJens WiklanderFUNC atomic_dec32 , :
44*e17dd72aSJens Wiklander	ldaxr	w1, [x0]
45*e17dd72aSJens Wiklander	sub	w1, w1, #1
46*e17dd72aSJens Wiklander	stxr	w2, w1, [x0]
47*e17dd72aSJens Wiklander	cmp	w2, #0
48*e17dd72aSJens Wiklander	bne	atomic_dec32
49*e17dd72aSJens Wiklander	mov	w0, w1
50*e17dd72aSJens Wiklander	ret
51*e17dd72aSJens WiklanderEND_FUNC atomic_dec32
52*e17dd72aSJens Wiklander
53