linux/arch/frv/lib/atomic-ops.S

63 lines
1.7 KiB
ArmAsm

/* atomic-ops.S: kernel atomic operations
*
* For an explanation of how atomic ops work in this arch, see:
* Documentation/frv/atomic-ops.txt
*
* Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include <asm/spr-regs.h>
.text
.balign 4
###############################################################################
#
# uint32_t __xchg_32(uint32_t i, uint32_t *v)
#
###############################################################################
.globl __xchg_32
.type __xchg_32,@function
__xchg_32:
or.p gr8,gr8,gr10
0:
orcc gr0,gr0,gr0,icc3 /* set ICC3.Z */
ckeq icc3,cc7
ld.p @(gr9,gr0),gr8 /* LD.P/ORCR must be atomic */
orcr cc7,cc7,cc3 /* set CC3 to true */
cst.p gr10,@(gr9,gr0) ,cc3,#1
corcc gr29,gr29,gr0 ,cc3,#1 /* clear ICC3.Z if store happens */
beq icc3,#0,0b
bralr
.size __xchg_32, .-__xchg_32
###############################################################################
#
# uint32_t __cmpxchg_32(uint32_t *v, uint32_t test, uint32_t new)
#
###############################################################################
.globl __cmpxchg_32
.type __cmpxchg_32,@function
__cmpxchg_32:
or.p gr8,gr8,gr11
0:
orcc gr0,gr0,gr0,icc3
ckeq icc3,cc7
ld.p @(gr11,gr0),gr8
orcr cc7,cc7,cc3
subcc gr8,gr9,gr7,icc0
bnelr icc0,#0
cst.p gr10,@(gr11,gr0) ,cc3,#1
corcc gr29,gr29,gr0 ,cc3,#1
beq icc3,#0,0b
bralr
.size __cmpxchg_32, .-__cmpxchg_32