1*0a6a1f1dSLionel Sambuc/* $NetBSD: atomic_sub_64.S,v 1.2 2014/03/04 16:15:28 matt Exp $ */ 284d9c625SLionel Sambuc 384d9c625SLionel Sambuc/*- 484d9c625SLionel Sambuc * Copyright (c) 2013 The NetBSD Foundation, Inc. 584d9c625SLionel Sambuc * All rights reserved. 684d9c625SLionel Sambuc * 784d9c625SLionel Sambuc * This code is derived from software contributed to The NetBSD Foundation 884d9c625SLionel Sambuc * by Matt Thomas <matt@3am-software.com> 984d9c625SLionel Sambuc * 1084d9c625SLionel Sambuc * Redistribution and use in source and binary forms, with or without 1184d9c625SLionel Sambuc * modification, are permitted provided that the following conditions 1284d9c625SLionel Sambuc * are met: 1384d9c625SLionel Sambuc * 1. Redistributions of source code must retain the above copyright 1484d9c625SLionel Sambuc * notice, this list of conditions and the following disclaimer. 1584d9c625SLionel Sambuc * 2. Redistributions in binary form must reproduce the above copyright 1684d9c625SLionel Sambuc * notice, this list of conditions and the following disclaimer in the 1784d9c625SLionel Sambuc * documentation and/or other materials provided with the distribution. 1884d9c625SLionel Sambuc * 1984d9c625SLionel Sambuc * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 2084d9c625SLionel Sambuc * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 2184d9c625SLionel Sambuc * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 2284d9c625SLionel Sambuc * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 2384d9c625SLionel Sambuc * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 2484d9c625SLionel Sambuc * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 2584d9c625SLionel Sambuc * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 2684d9c625SLionel Sambuc * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 2784d9c625SLionel Sambuc * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 2884d9c625SLionel Sambuc * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 2984d9c625SLionel Sambuc * POSSIBILITY OF SUCH DAMAGE. 3084d9c625SLionel Sambuc */ 3184d9c625SLionel Sambuc 3284d9c625SLionel Sambuc#include "atomic_op_asm.h" 3384d9c625SLionel Sambuc 3484d9c625SLionel Sambuc#ifdef _ARM_ARCH_6 3584d9c625SLionel Sambuc 3684d9c625SLionel SambucENTRY_NP(_atomic_sub_64_nv) 3784d9c625SLionel Sambuc push {r3,r4} /* save temporary */ 3884d9c625SLionel Sambuc mov ip, r0 /* need r0 for return value */ 3984d9c625SLionel Sambuc#ifndef __ARM_EABI__ 4084d9c625SLionel Sambuc mov r3, r2 4184d9c625SLionel Sambuc mov r2, r1 4284d9c625SLionel Sambuc#endif 4384d9c625SLionel Sambuc1: ldrexd r0, [ip] /* load old value */ 4484d9c625SLionel Sambuc subs LO, LO, NLO /* calculate new value lo */ 4584d9c625SLionel Sambuc sbcs HI, HI, NHI /* calculate new value hi */ 4684d9c625SLionel Sambuc strexd r4, r0, [ip] /* try to store */ 4784d9c625SLionel Sambuc cmp r4, #0 /* succeed? */ 4884d9c625SLionel Sambuc bne 1b /* no, try again? */ 4984d9c625SLionel Sambuc#ifdef _ARM_ARCH_7 5084d9c625SLionel Sambuc dmb 5184d9c625SLionel Sambuc#else 5284d9c625SLionel Sambuc mcr p15, 0, r4, c7, c10, 5 /* data memory barrier */ 5384d9c625SLionel Sambuc#endif 5484d9c625SLionel Sambuc pop {r3,r4} /* restore temporary */ 5584d9c625SLionel Sambuc RET /* return new value */ 5684d9c625SLionel SambucEND(_atomic_sub_64_nv) 5784d9c625SLionel Sambuc 5884d9c625SLionel SambucSTRONG_ALIAS(_atomic_sub_64,_atomic_sub_64_nv) 5984d9c625SLionel SambucATOMIC_OP_ALIAS(atomic_sub_64_nv,_atomic_sub_64_nv) 6084d9c625SLionel SambucATOMIC_OP_ALIAS(atomic_sub_64,_atomic_sub_64) 61*0a6a1f1dSLionel SambucCRT_ALIAS(__sync_sub_and_fetch_8,_atomic_sub_64_nv) 6284d9c625SLionel Sambuc 6384d9c625SLionel Sambuc#endif /* _ARM_ARCH_6 */ 64