/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_S390_RUNTIME_CONST_H
#define _ASM_S390_RUNTIME_CONST_H

#include <linux/uaccess.h>

#define runtime_const_ptr(sym)                                  \
({                                                              \
        typeof(sym) __ret;                                      \
                                                                \
        asm_inline(                                             \
                "0:     iihf    %[__ret],%[c1]\n"               \
                "       iilf    %[__ret],%[c2]\n"               \
                ".pushsection runtime_ptr_" #sym ",\"a\"\n"     \
                ".long 0b - .\n"                                \
                ".popsection"                                   \
                : [__ret] "=d" (__ret)                          \
                : [c1] "i" (0x01234567UL),                      \
                  [c2] "i" (0x89abcdefUL));                     \
        __ret;                                                  \
})

#define runtime_const_shift_right_32(val, sym)                  \
({                                                              \
        unsigned int __ret = (val);                             \
                                                                \
        asm_inline(                                             \
                "0:     srl     %[__ret],12\n"                  \
                ".pushsection runtime_shift_" #sym ",\"a\"\n"   \
                ".long 0b - .\n"                                \
                ".popsection"                                   \
                : [__ret] "+d" (__ret));                        \
        __ret;                                                  \
})

#define runtime_const_init(type, sym) do {                      \
        extern s32 __start_runtime_##type##_##sym[];            \
        extern s32 __stop_runtime_##type##_##sym[];             \
                                                                \
        runtime_const_fixup(__runtime_fixup_##type,             \
                            (unsigned long)(sym),               \
                            __start_runtime_##type##_##sym,     \
                            __stop_runtime_##type##_##sym);     \
} while (0)

/* 32-bit immediate for iihf and iilf in bits in I2 field */
static inline void __runtime_fixup_32(u32 *p, unsigned int val)
{
        s390_kernel_write(p, &val, sizeof(val));
}

static inline void __runtime_fixup_ptr(void *where, unsigned long val)
{
        __runtime_fixup_32(where + 2, val >> 32);
        __runtime_fixup_32(where + 8, val);
}

/* Immediate value is lower 12 bits of D2 field of srl */
static inline void __runtime_fixup_shift(void *where, unsigned long val)
{
        u32 insn = *(u32 *)where;

        insn &= 0xfffff000;
        insn |= (val & 63);
        s390_kernel_write(where, &insn, sizeof(insn));
}

static inline void runtime_const_fixup(void (*fn)(void *, unsigned long),
                                       unsigned long val, s32 *start, s32 *end)
{
        while (start < end) {
                fn(*start + (void *)start, val);
                start++;
        }
}

#endif /* _ASM_S390_RUNTIME_CONST_H */