qoriq/mpci/lock.S

0001 /* SPDX-License-Identifier: BSD-2-Clause */
0002
0003 /**
0004  * @file
0005  *
0006  * @ingroup RTEMSBSPsPowerPCQorIQInterCom
0007  *
0008  * @brief qoriq_spin_lock() and qoriq_spin_unlock() implementation.
0009  */
0010
0011 /*
0012  * Copyright (c) 2011 embedded brains GmbH & Co. KG
0013  *
0014  * Redistribution and use in source and binary forms, with or without
0015  * modification, are permitted provided that the following conditions
0016  * are met:
0017  * 1. Redistributions of source code must retain the above copyright
0018  *    notice, this list of conditions and the following disclaimer.
0019  * 2. Redistributions in binary form must reproduce the above copyright
0020  *    notice, this list of conditions and the following disclaimer in the
0021  *    documentation and/or other materials provided with the distribution.
0022  *
0023  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
0024  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
0025  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
0026  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
0027  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
0028  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
0029  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
0030  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
0031  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
0032  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
0033  * POSSIBILITY OF SUCH DAMAGE.
0034  */
0035
0036 #include <libcpu/powerpc-utility.h>
0037
0038     .global qoriq_spin_lock
0039     .global qoriq_spin_unlock
0040
0041 qoriq_spin_lock:
0042     li  r0, 1
0043     mfmsr   r4
0044     GET_INTERRUPT_MASK r5
0045     andc    r5, r4, r5
0046     b   2f
0047 1:
0048     mtmsr   r4
0049 2:
0050     lwarx   r6, r0, r3
0051     cmpwi   r6, 0
0052     bne 2b
0053     mtmsr   r5
0054     stwcx.  r0, r0, r3
0055     bne 1b
0056     isync
0057     mr  r3, r4
0058     blr
0059
0060 qoriq_spin_unlock:
0061     msync
0062     li  r0, 0
0063     stw r0, 0(r3)
0064     mtmsr   r4
0065     blr