/* SPDX-License-Identifier: GPL-2.0-only */
/*
 * Copyright (C) 2012 ARM Ltd.
 */
#ifndef __ASM_MODULE_H
#define __ASM_MODULE_H

#include <asm-generic/module.h>

struct mod_plt_sec {
        int                     plt_shndx;
        int                     plt_num_entries;
        int                     plt_max_entries;
};

struct mod_arch_specific {
        struct mod_plt_sec      core;
        struct mod_plt_sec      init;

        /* for CONFIG_DYNAMIC_FTRACE */
        struct plt_entry        *ftrace_trampolines;
        struct plt_entry        *init_ftrace_trampolines;
};

u64 module_emit_plt_entry(struct module *mod, Elf64_Shdr *sechdrs,
                          void *loc, const Elf64_Rela *rela,
                          Elf64_Sym *sym);

u64 module_emit_veneer_for_adrp(struct module *mod, Elf64_Shdr *sechdrs,
                                void *loc, u64 val);

struct plt_entry {
        /*
         * A program that conforms to the AArch64 Procedure Call Standard
         * (AAPCS64) must assume that a veneer that alters IP0 (x16) and/or
         * IP1 (x17) may be inserted at any branch instruction that is
         * exposed to a relocation that supports long branches. Since that
         * is exactly what we are dealing with here, we are free to use x16
         * as a scratch register in the PLT veneers.
         */
        __le32  adrp;   /* adrp x16, ....                       */
        __le32  add;    /* add  x16, x16, #0x....               */
        __le32  br;     /* br   x16                             */
};

static inline bool is_forbidden_offset_for_adrp(void *place)
{
        return cpus_have_final_cap(ARM64_WORKAROUND_843419) &&
               ((u64)place & 0xfff) >= 0xff8;
}

struct plt_entry get_plt_entry(u64 dst, void *pc);

static inline const Elf_Shdr *find_section(const Elf_Ehdr *hdr,
                                    const Elf_Shdr *sechdrs,
                                    const char *name)
{
        const Elf_Shdr *s, *se;
        const char *secstrs = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;

        for (s = sechdrs, se = sechdrs + hdr->e_shnum; s < se; s++) {
                if (strcmp(name, secstrs + s->sh_name) == 0)
                        return s;
        }

        return NULL;
}

#endif /* __ASM_MODULE_H */