1/* atomic-ops.S: kernel atomic operations
2 *
3 * For an explanation of how atomic ops work in this arch, see:
4 *   Documentation/frv/atomic-ops.txt
5 *
6 * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
7 * Written by David Howells (dhowells@redhat.com)
8 *
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License
11 * as published by the Free Software Foundation; either version
12 * 2 of the License, or (at your option) any later version.
13 */
14
15#include <asm/spr-regs.h>
16
17	.text
18	.balign 4
19
20###############################################################################
21#
22# uint32_t __xchg_32(uint32_t i, uint32_t *v)
23#
24###############################################################################
25	.globl		__xchg_32
26        .type		__xchg_32,@function
27__xchg_32:
28	or.p		gr8,gr8,gr10
290:
30	orcc		gr0,gr0,gr0,icc3		/* set ICC3.Z */
31	ckeq		icc3,cc7
32	ld.p		@(gr9,gr0),gr8			/* LD.P/ORCR must be atomic */
33	orcr		cc7,cc7,cc3			/* set CC3 to true */
34	cst.p		gr10,@(gr9,gr0)		,cc3,#1
35	corcc		gr29,gr29,gr0		,cc3,#1	/* clear ICC3.Z if store happens */
36	beq		icc3,#0,0b
37	bralr
38
39	.size		__xchg_32, .-__xchg_32
40
41###############################################################################
42#
43# uint32_t __cmpxchg_32(uint32_t *v, uint32_t test, uint32_t new)
44#
45###############################################################################
46	.globl		__cmpxchg_32
47        .type		__cmpxchg_32,@function
48__cmpxchg_32:
49	or.p		gr8,gr8,gr11
500:
51	orcc		gr0,gr0,gr0,icc3
52	ckeq		icc3,cc7
53	ld.p		@(gr11,gr0),gr8
54	orcr		cc7,cc7,cc3
55	subcc		gr8,gr9,gr7,icc0
56	bnelr		icc0,#0
57	cst.p		gr10,@(gr11,gr0)	,cc3,#1
58	corcc		gr29,gr29,gr0		,cc3,#1
59	beq		icc3,#0,0b
60	bralr
61
62	.size		__cmpxchg_32, .-__cmpxchg_32
63