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/* SPDX-License-Identifier: GPL-2.0 */
#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 arch_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 arch_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_FETCH_OP(op) \
static inline int arch_atomic_fetch_##op(int i, atomic_t *v) \
{ \
unsigned long res, temp; \
\
__asm__ __volatile__ ( \
"1: movli.l @%3, %0 ! atomic_fetch_" #op " \n" \
" mov %0, %1 \n" \
" " #op " %2, %0 \n" \
" movco.l %0, @%3 \n" \
" bf 1b \n" \
" synco \n" \
: "=&z" (temp), "=&r" (res) \
: "r" (i), "r" (&v->counter) \
: "t"); \
\
return res; \
}
#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_OP_RETURN(op) ATOMIC_FETCH_OP(op)
ATOMIC_OPS(add)
ATOMIC_OPS(sub)
#undef ATOMIC_OPS
#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_FETCH_OP(op)
ATOMIC_OPS(and)
ATOMIC_OPS(or)
ATOMIC_OPS(xor)
#undef ATOMIC_OPS
#undef ATOMIC_FETCH_OP
#undef ATOMIC_OP_RETURN
#undef ATOMIC_OP
#endif /* __ASM_SH_ATOMIC_LLSC_H */
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