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/* SPDX-License-Identifier: BSD-3-Clause */
/*
* Copyright (c) 2016, Linaro Limited
* Copyright (c) 2016, ARM Limited and Contributors. All rights reserved.
* Copyright (c) 2014, STMicroelectronics International N.V.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* Neither the name of ARM nor the names of its contributors may be used
* to endorse or promote products derived from this software without specific
* prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include <asm.S>
#include <kernel/spinlock.h>
/* void __cpu_spin_lock(unsigned int *lock) */
FUNC __cpu_spin_lock , :
mov r2, #SPINLOCK_LOCK
1:
ldrex r1, [r0]
cmp r1, #SPINLOCK_UNLOCK
wfene
strexeq r1, r2, [r0]
cmpeq r1, #0
bne 1b
dmb
bx lr
END_FUNC __cpu_spin_lock
/* int __cpu_spin_trylock(unsigned int *lock) - return 0 on success */
FUNC __cpu_spin_trylock , :
mov r2, #SPINLOCK_LOCK
mov r1, r0
1:
ldrex r0, [r1]
cmp r0, #0
bne 1f
strex r0, r2, [r1]
cmp r0, #0
bne 1b
dmb
bx lr
1:
clrex
dmb
bx lr
END_FUNC __cpu_spin_trylock
/* void __cpu_spin_unlock(unsigned int *lock) */
FUNC __cpu_spin_unlock , :
dmb
mov r1, #SPINLOCK_UNLOCK
str r1, [r0]
dsb
sev
bx lr
END_FUNC __cpu_spin_unlock
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