/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_MICROBLAZE_FUTEX_H
#define _ASM_MICROBLAZE_FUTEX_H

#ifdef __KERNEL__

#include <linux/futex.h>
#include <linux/uaccess.h>
#include <asm/errno.h>

#define __futex_atomic_op(insn, ret, oldval, uaddr, oparg) \
({                                                                      \
        __asm__ __volatile__ (                                          \
                        "1:     lwx     %0, %2, r0; "                   \
                                insn                                    \
                        "2:     swx     %1, %2, r0;                     \
                                addic   %1, r0, 0;                      \
                                bnei    %1, 1b;                         \
                        3:                                              \
                        .section .fixup,\"ax\";                         \
                        4:      brid    3b;                             \
                                addik   %1, r0, %3;                     \
                        .previous;                                      \
                        .section __ex_table,\"a\";                      \
                        .word   1b,4b,2b,4b;                            \
                        .previous;"                                     \
        : "=&r" (oldval), "=&r" (ret)                                   \
        : "r" (uaddr), "i" (-EFAULT), "r" (oparg)                       \
        );                                                              \
})

static inline int
arch_futex_atomic_op_inuser(int op, int oparg, int *oval, u32 __user *uaddr)
{
        int oldval = 0, ret;

        if (!access_ok(uaddr, sizeof(u32)))
                return -EFAULT;

        switch (op) {
        case FUTEX_OP_SET:
                __futex_atomic_op("or %1,%4,%4;", ret, oldval, uaddr, oparg);
                break;
        case FUTEX_OP_ADD:
                __futex_atomic_op("add %1,%0,%4;", ret, oldval, uaddr, oparg);
                break;
        case FUTEX_OP_OR:
                __futex_atomic_op("or %1,%0,%4;", ret, oldval, uaddr, oparg);
                break;
        case FUTEX_OP_ANDN:
                __futex_atomic_op("andn %1,%0,%4;", ret, oldval, uaddr, oparg);
                break;
        case FUTEX_OP_XOR:
                __futex_atomic_op("xor %1,%0,%4;", ret, oldval, uaddr, oparg);
                break;
        default:
                ret = -ENOSYS;
        }

        if (!ret)
                *oval = oldval;

        return ret;
}

static inline int
futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
                              u32 oldval, u32 newval)
{
        int ret = 0, cmp;
        u32 prev;

        if (!access_ok(uaddr, sizeof(u32)))
                return -EFAULT;

        __asm__ __volatile__ ("1:       lwx     %1, %3, r0;             \
                                        cmp     %2, %1, %4;             \
                                        bnei    %2, 3f;                 \
                                2:      swx     %5, %3, r0;             \
                                        addic   %2, r0, 0;              \
                                        bnei    %2, 1b;                 \
                                3:                                      \
                                .section .fixup,\"ax\";                 \
                                4:      brid    3b;                     \
                                        addik   %0, r0, %6;             \
                                .previous;                              \
                                .section __ex_table,\"a\";              \
                                .word   1b,4b,2b,4b;                    \
                                .previous;"                             \
                : "+r" (ret), "=&r" (prev), "=&r"(cmp)  \
                : "r" (uaddr), "r" (oldval), "r" (newval), "i" (-EFAULT));

        *uval = prev;
        return ret;
}

#endif /* __KERNEL__ */

#endif