blob: 33d34b16d4d67bb15ed129d1233c110640de9d7b [file] [log] [blame]
#ifndef __ASM_SH_ATOMIC_LLSC_H
#define __ASM_SH_ATOMIC_LLSC_H
/*
* SH-4A note:
*
* We basically get atomic_xxx_return() for free compared with
* atomic_xxx(). movli.l/movco.l require r0 due to the instruction
* encoding, so the retval is automatically set without having to
* do any special work.
*/
/*
* To get proper branch prediction for the main line, we must branch
* forward to code at the end of this object's .text section, then
* branch back to restart the operation.
*/
#define ATOMIC_OP(op) \
static inline void atomic_##op(int i, atomic_t *v) \
{ \
unsigned long tmp; \
\
__asm__ __volatile__ ( \
"1: movli.l @%2, %0 ! atomic_" #op "\n" \
" " #op " %1, %0 \n" \
" movco.l %0, @%2 \n" \
" bf 1b \n" \
: "=&z" (tmp) \
: "r" (i), "r" (&v->counter) \
: "t"); \
}
#define ATOMIC_OP_RETURN(op) \
static inline int atomic_##op##_return(int i, atomic_t *v) \
{ \
unsigned long temp; \
\
__asm__ __volatile__ ( \
"1: movli.l @%2, %0 ! atomic_" #op "_return \n" \
" " #op " %1, %0 \n" \
" movco.l %0, @%2 \n" \
" bf 1b \n" \
" synco \n" \
: "=&z" (temp) \
: "r" (i), "r" (&v->counter) \
: "t"); \
\
return temp; \
}
#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_OP_RETURN(op)
ATOMIC_OPS(add)
ATOMIC_OPS(sub)
ATOMIC_OP(and)
ATOMIC_OP(or)
ATOMIC_OP(xor)
#undef ATOMIC_OPS
#undef ATOMIC_OP_RETURN
#undef ATOMIC_OP
#endif /* __ASM_SH_ATOMIC_LLSC_H */