1/* $NetBSD: atomic_xor_8.S,v 1.3 2014/06/23 21:53:45 joerg Exp $ */ 2 3/*- 4 * Copyright (c) 2013 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Matt Thomas <matt@3am-software.com> 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32#include "atomic_op_asm.h" 33 34#ifdef _ARM_ARCH_6 35 36ENTRY_NP(_atomic_xor_8) 37 mov ip, r0 381: ldrexb r0, [ip] /* load old value (to be returned) */ 39 eors r3, r0, r1 /* calculate new value */ 40 strexb r2, r3, [ip] /* try to store */ 41 cmp r2, #0 /* succeed? */ 42 bne 1b /* no, try again */ 43#ifdef _ARM_ARCH_7 44 dmb 45#else 46 mcr p15, 0, r2, c7, c10, 5 /* data memory barrier */ 47#endif 48 RET /* return old value */ 49END(_atomic_xor_8) 50 51ATOMIC_OP_ALIAS(atomic_xor_8,_atomic_xor_8) 52ATOMIC_OP_ALIAS(atomic_xor_uchar,_atomic_xor_8) 53CRT_ALIAS(__sync_fetch_and_xor_1,_atomic_xor_8) 54CRT_ALIAS(__atomic_fetch_xor_1,_atomic_xor_8) 55STRONG_ALIAS(_atomic_xor_uchar,_atomic_xor_8) 56 57ENTRY_NP(_atomic_xor_8_nv) 58 mov ip, r0 /* need r0 for return value */ 591: ldrexb r0, [ip] /* load old value */ 60 eors r0, r0, r1 /* calculate new value (return value) */ 61 strexb r2, r0, [ip] /* try to store */ 62 cmp r2, #0 /* succeed? */ 63 bne 1b /* no, try again? */ 64#ifdef _ARM_ARCH_7 65 dmb 66#else 67 mcr p15, 0, r2, c7, c10, 5 /* data memory barrier */ 68#endif 69 RET /* return new value */ 70END(_atomic_xor_8_nv) 71 72ATOMIC_OP_ALIAS(atomic_xor_8_nv,_atomic_xor_8_nv) 73ATOMIC_OP_ALIAS(atomic_xor_uchar_nv,_atomic_xor_8_nv) 74CRT_ALIAS(__sync_xor_and_fetch_1,_atomic_xor_8_nv) 75STRONG_ALIAS(_atomic_xor_uchar_nv,_atomic_xor_8_nv) 76 77#endif /* _ARM_ARCH_6 */ 78