/*
* Copyright (C) 2005 Ondrej Palkovsky
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* - 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.
* - The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
*/
#ifndef __mips32_ATOMIC_H__
#define __mips32_ATOMIC_H__
#define atomic_inc(x) ((void) atomic_add(x, 1))
#define atomic_dec(x) ((void) atomic_add(x, -1))
#define atomic_postinc(x) (atomic_add(x, 1) - 1)
#define atomic_postdec(x) (atomic_add(x, -1) + 1)
#define atomic_preinc(x) atomic_add(x, 1)
#define atomic_predec(x) atomic_add(x, -1)
/* Atomic addition of immediate value.
*
* @param val Memory location to which will be the immediate value added.
* @param i Signed immediate that will be added to *val.
*
* @return Value after addition.
*/
static inline long atomic_add(atomic_t *val, int i)
{
long tmp, v;
__asm__ volatile (
"1:\n"
" ll %0, %1\n"
" addiu %0, %0, %3\n" /* same as addi, but never traps on overflow */
" move %2, %0\n"
" sc %0, %1\n"
" beq %0, %4, 1b\n" /* if the atomic operation failed, try again */
/* nop */ /* nop is inserted automatically by compiler */
: "=r" (tmp), "=m" (val->count), "=r" (v)
: "i" (i), "i" (0)
);
return v;
}
#endif