/* 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)

#define arch_atomic_add_return  arch_atomic_add_return
#define arch_atomic_sub_return  arch_atomic_sub_return
#define arch_atomic_fetch_add   arch_atomic_fetch_add
#define arch_atomic_fetch_sub   arch_atomic_fetch_sub

#undef ATOMIC_OPS
#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_FETCH_OP(op)

ATOMIC_OPS(and)
ATOMIC_OPS(or)
ATOMIC_OPS(xor)

#define arch_atomic_fetch_and   arch_atomic_fetch_and
#define arch_atomic_fetch_or    arch_atomic_fetch_or
#define arch_atomic_fetch_xor   arch_atomic_fetch_xor

#undef ATOMIC_OPS
#undef ATOMIC_FETCH_OP
#undef ATOMIC_OP_RETURN
#undef ATOMIC_OP

#endif /* __ASM_SH_ATOMIC_LLSC_H */