/* SPDX-License-Identifier: GPL-2.0-or-later */
#ifndef _ASM_POWERPC_INST_H
#define _ASM_POWERPC_INST_H

#include <asm/ppc-opcode.h>
#include <asm/reg.h>
#include <asm/disassemble.h>
#include <asm/uaccess.h>

#define ___get_user_instr(gu_op, dest, ptr)                             \
({                                                                      \
        long __gui_ret;                                                 \
        u32 __user *__gui_ptr = (u32 __user *)ptr;                      \
        ppc_inst_t __gui_inst;                                          \
        unsigned int __prefix, __suffix;                                \
                                                                        \
        __chk_user_ptr(ptr);                                            \
        __gui_ret = gu_op(__prefix, __gui_ptr);                         \
        if (__gui_ret == 0) {                                           \
                if (IS_ENABLED(CONFIG_PPC64) && (__prefix >> 26) == OP_PREFIX) { \
                        __gui_ret = gu_op(__suffix, __gui_ptr + 1);     \
                        __gui_inst = ppc_inst_prefix(__prefix, __suffix); \
                } else {                                                \
                        __gui_inst = ppc_inst(__prefix);                \
                }                                                       \
                if (__gui_ret == 0)                                     \
                        (dest) = __gui_inst;                            \
        }                                                               \
        __gui_ret;                                                      \
})

#define get_user_instr(x, ptr) ___get_user_instr(get_user, x, ptr)

#define __get_user_instr(x, ptr) ___get_user_instr(__get_user, x, ptr)

/*
 * Instruction data type for POWER
 */

#if defined(CONFIG_PPC64) || defined(__CHECKER__)
static inline u32 ppc_inst_val(ppc_inst_t x)
{
        return x.val;
}

#define ppc_inst(x) ((ppc_inst_t){ .val = (x) })

#else
static inline u32 ppc_inst_val(ppc_inst_t x)
{
        return x;
}
#define ppc_inst(x) (x)
#endif

static inline int ppc_inst_primary_opcode(ppc_inst_t x)
{
        return ppc_inst_val(x) >> 26;
}

#ifdef CONFIG_PPC64
#define ppc_inst_prefix(x, y) ((ppc_inst_t){ .val = (x), .suffix = (y) })

static inline u32 ppc_inst_suffix(ppc_inst_t x)
{
        return x.suffix;
}

#else
#define ppc_inst_prefix(x, y) ((void)y, ppc_inst(x))

static inline u32 ppc_inst_suffix(ppc_inst_t x)
{
        return 0;
}

#endif /* CONFIG_PPC64 */

static inline ppc_inst_t ppc_inst_read(const u32 *ptr)
{
        if (IS_ENABLED(CONFIG_PPC64) && (*ptr >> 26) == OP_PREFIX)
                return ppc_inst_prefix(*ptr, *(ptr + 1));
        else
                return ppc_inst(*ptr);
}

static inline bool ppc_inst_prefixed(ppc_inst_t x)
{
        return IS_ENABLED(CONFIG_PPC64) && ppc_inst_primary_opcode(x) == OP_PREFIX;
}

static inline ppc_inst_t ppc_inst_swab(ppc_inst_t x)
{
        return ppc_inst_prefix(swab32(ppc_inst_val(x)), swab32(ppc_inst_suffix(x)));
}

static inline bool ppc_inst_equal(ppc_inst_t x, ppc_inst_t y)
{
        if (ppc_inst_val(x) != ppc_inst_val(y))
                return false;
        if (!ppc_inst_prefixed(x))
                return true;
        return ppc_inst_suffix(x) == ppc_inst_suffix(y);
}

static inline int ppc_inst_len(ppc_inst_t x)
{
        return ppc_inst_prefixed(x) ? 8 : 4;
}

/*
 * Return the address of the next instruction, if the instruction @value was
 * located at @location.
 */
static inline u32 *ppc_inst_next(u32 *location, u32 *value)
{
        ppc_inst_t tmp;

        tmp = ppc_inst_read(value);

        return (void *)location + ppc_inst_len(tmp);
}

static inline unsigned long ppc_inst_as_ulong(ppc_inst_t x)
{
        if (IS_ENABLED(CONFIG_PPC32))
                return ppc_inst_val(x);
        else if (IS_ENABLED(CONFIG_CPU_LITTLE_ENDIAN))
                return (u64)ppc_inst_suffix(x) << 32 | ppc_inst_val(x);
        else
                return (u64)ppc_inst_val(x) << 32 | ppc_inst_suffix(x);
}

static inline void ppc_inst_write(u32 *ptr, ppc_inst_t x)
{
        if (!ppc_inst_prefixed(x))
                *ptr = ppc_inst_val(x);
        else
                *(u64 *)ptr = ppc_inst_as_ulong(x);
}

static inline int __copy_inst_from_kernel_nofault(ppc_inst_t *inst, u32 *src)
{
        unsigned int val, suffix;

        __get_kernel_nofault(&val, src, u32, Efault);
        if (IS_ENABLED(CONFIG_PPC64) && get_op(val) == OP_PREFIX) {
                __get_kernel_nofault(&suffix, src + 1, u32, Efault);
                *inst = ppc_inst_prefix(val, suffix);
        } else {
                *inst = ppc_inst(val);
        }
        return 0;
Efault:
        return -EFAULT;
}

static inline int copy_inst_from_kernel_nofault(ppc_inst_t *inst, u32 *src)
{
        if (unlikely(!is_kernel_addr((unsigned long)src)))
                return -ERANGE;

        return __copy_inst_from_kernel_nofault(inst, src);
}

#endif /* _ASM_POWERPC_INST_H */