cmpxchg.h
/*
* Port on Texas Instruments TMS320C6x architecture
*
* Copyright (C) 2004, 2009, 2010, 2011 Texas Instruments Incorporated
* Author: Aurelien Jacquiot (aurelien.jacquiot@jaluna.com)
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#ifndef _ASM_C6X_CMPXCHG_H
#define _ASM_C6X_CMPXCHG_H
#include <linux/irqflags.h>
/*
* Misc. functions
*/
static inline unsigned int __xchg(unsigned int x, volatile void *ptr, int size)
{
unsigned int tmp;
unsigned long flags;
local_irq_save(flags);
switch (size) {
case 1:
tmp = 0;
tmp = *((unsigned char *) ptr);
*((unsigned char *) ptr) = (unsigned char) x;
break;
case 2:
tmp = 0;
tmp = *((unsigned short *) ptr);
*((unsigned short *) ptr) = x;
break;
case 4:
tmp = 0;
tmp = *((unsigned int *) ptr);
*((unsigned int *) ptr) = x;
break;
}
local_irq_restore(flags);
return tmp;
}
#define xchg(ptr, x) \
((__typeof__(*(ptr)))__xchg((unsigned int)(x), (void *) (ptr), \
sizeof(*(ptr))))
#define tas(ptr) xchg((ptr), 1)
#include <asm-generic/cmpxchg-local.h>
/*
* cmpxchg_local and cmpxchg64_local are atomic wrt current CPU. Always make
* them available.
*/
#define cmpxchg_local(ptr, o, n) \
((__typeof__(*(ptr)))__cmpxchg_local_generic((ptr), \
(unsigned long)(o), \
(unsigned long)(n), \
sizeof(*(ptr))))
#define cmpxchg64_local(ptr, o, n) __cmpxchg64_local_generic((ptr), (o), (n))
#include <asm-generic/cmpxchg.h>
#endif /* _ASM_C6X_CMPXCHG_H */