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/* xchg and cmpxchg operation emulation for FR-V
*
* For an explanation of how atomic ops work in this arch, see:
* Documentation/frv/atomic-ops.txt
*
* Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#ifndef _ASM_CMPXCHG_H
#define _ASM_CMPXCHG_H
#include <linux/types.h>
/*****************************************************************************/
/*
* exchange value with memory
*/
extern uint64_t __xchg_64(uint64_t i, volatile void *v);
#ifndef CONFIG_FRV_OUTOFLINE_ATOMIC_OPS
#define xchg(ptr, x) \
({ \
__typeof__(ptr) __xg_ptr = (ptr); \
__typeof__(*(ptr)) __xg_orig; \
\
switch (sizeof(__xg_orig)) { \
case 4: \
asm volatile( \
"swap%I0 %M0,%1" \
: "+m"(*__xg_ptr), "=r"(__xg_orig) \
: "1"(x) \
: "memory" \
); \
break; \
\
default: \
__xg_orig = (__typeof__(__xg_orig))0; \
asm volatile("break"); \
break; \
} \
\
__xg_orig; \
})
#else
extern uint32_t __xchg_32(uint32_t i, volatile void *v);
#define xchg(ptr, x) \
({ \
__typeof__(ptr) __xg_ptr = (ptr); \
__typeof__(*(ptr)) __xg_orig; \
\
switch (sizeof(__xg_orig)) { \
case 4: __xg_orig = (__typeof__(*(ptr))) __xchg_32((uint32_t) x, __xg_ptr); break; \
default: \
__xg_orig = (__typeof__(__xg_orig))0; \
asm volatile("break"); \
break; \
} \
__xg_orig; \
})
#endif
#define tas(ptr) (xchg((ptr), 1))
/*****************************************************************************/
/*
* compare and conditionally exchange value with memory
* - if (*ptr == test) then orig = *ptr; *ptr = test;
* - if (*ptr != test) then orig = *ptr;
*/
extern uint64_t __cmpxchg_64(uint64_t test, uint64_t new, volatile uint64_t *v);
#ifndef CONFIG_FRV_OUTOFLINE_ATOMIC_OPS
#define cmpxchg(ptr, test, new) \
({ \
__typeof__(ptr) __xg_ptr = (ptr); \
__typeof__(*(ptr)) __xg_orig, __xg_tmp; \
__typeof__(*(ptr)) __xg_test = (test); \
__typeof__(*(ptr)) __xg_new = (new); \
\
switch (sizeof(__xg_orig)) { \
case 4: \
asm volatile( \
"0: \n" \
" orcc gr0,gr0,gr0,icc3 \n" \
" ckeq icc3,cc7 \n" \
" ld.p %M0,%1 \n" \
" orcr cc7,cc7,cc3 \n" \
" sub%I4cc %1,%4,%2,icc0 \n" \
" bne icc0,#0,1f \n" \
" cst.p %3,%M0 ,cc3,#1 \n" \
" corcc gr29,gr29,gr0 ,cc3,#1 \n" \
" beq icc3,#0,0b \n" \
"1: \n" \
: "+U"(*__xg_ptr), "=&r"(__xg_orig), "=&r"(__xg_tmp) \
: "r"(__xg_new), "NPr"(__xg_test) \
: "memory", "cc7", "cc3", "icc3", "icc0" \
); \
break; \
\
default: \
__xg_orig = (__typeof__(__xg_orig))0; \
asm volatile("break"); \
break; \
} \
\
__xg_orig; \
})
#else
extern uint32_t __cmpxchg_32(uint32_t *v, uint32_t test, uint32_t new);
#define cmpxchg(ptr, test, new) \
({ \
__typeof__(ptr) __xg_ptr = (ptr); \
__typeof__(*(ptr)) __xg_orig; \
__typeof__(*(ptr)) __xg_test = (test); \
__typeof__(*(ptr)) __xg_new = (new); \
\
switch (sizeof(__xg_orig)) { \
case 4: __xg_orig = (__force __typeof__(*ptr)) \
__cmpxchg_32((__force uint32_t *)__xg_ptr, \
(__force uint32_t)__xg_test, \
(__force uint32_t)__xg_new); break; \
default: \
__xg_orig = (__typeof__(__xg_orig))0; \
asm volatile("break"); \
break; \
} \
\
__xg_orig; \
})
#endif
#include <asm-generic/cmpxchg-local.h>
static inline unsigned long __cmpxchg_local(volatile void *ptr,
unsigned long old,
unsigned long new, int size)
{
switch (size) {
case 4:
return cmpxchg((unsigned long *)ptr, old, new);
default:
return __cmpxchg_local_generic(ptr, old, new, size);
}
return old;
}
/*
* cmpxchg_local and cmpxchg64_local are atomic wrt current CPU. Always make
* them available.
*/
#define cmpxchg_local(ptr, o, n) \
((__typeof__(*(ptr)))__cmpxchg_local((ptr), (unsigned long)(o), \
(unsigned long)(n), sizeof(*(ptr))))
#define cmpxchg64_local(ptr, o, n) __cmpxchg64_local_generic((ptr), (o), (n))
#endif /* _ASM_CMPXCHG_H */
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