Orange Pi5 kernel

/* SPDX-License-Identifier: GPL-2.0 */
/* Copyright (C) 2017 Andes Technology Corporation */
 
#ifndef _ASM_RISCV_MODULE_H
#define _ASM_RISCV_MODULE_H
 
#include <asm-generic/module.h>
 
struct module;
unsigned long module_emit_got_entry(struct module *mod, unsigned long val);
unsigned long module_emit_plt_entry(struct module *mod, unsigned long val);
 
#ifdef CONFIG_MODULE_SECTIONS
struct mod_section {
<------>Elf_Shdr *shdr;
<------>int num_entries;
<------>int max_entries;
};
 
struct mod_arch_specific {
<------>struct mod_section got;
<------>struct mod_section plt;
<------>struct mod_section got_plt;
};
 
struct got_entry {
<------>unsigned long symbol_addr;	/* the real variable address */
};
 
static inline struct got_entry emit_got_entry(unsigned long val)
{
<------>return (struct got_entry) {val};
}
 
static inline struct got_entry *get_got_entry(unsigned long val,
<------><------><------><------><------>      const struct mod_section *sec)
{
<------>struct got_entry *got = (struct got_entry *)(sec->shdr->sh_addr);
<------>int i;
<------>for (i = 0; i < sec->num_entries; i++) {
<------><------>if (got[i].symbol_addr == val)
<------><------><------>return &got[i];
<------>}
<------>return NULL;
}
 
struct plt_entry {
<------>/*
<------> * Trampoline code to real target address. The return address
<------> * should be the original (pc+4) before entring plt entry.
<------> */
<------>u32 insn_auipc;		/* auipc t0, 0x0                       */
<------>u32 insn_ld;		/* ld    t1, 0x10(t0)                  */
<------>u32 insn_jr;		/* jr    t1                            */
};
 
#define OPC_AUIPC  0x0017
#define OPC_LD     0x3003
#define OPC_JALR   0x0067
#define REG_T0     0x5
#define REG_T1     0x6
 
static inline struct plt_entry emit_plt_entry(unsigned long val,
<------><------><------><------><------>      unsigned long plt,
<------><------><------><------><------>      unsigned long got_plt)
{
<------>/*
<------> * U-Type encoding:
<------> * +------------+----------+----------+
<------> * | imm[31:12] | rd[11:7] | opc[6:0] |
<------> * +------------+----------+----------+
<------> *
<------> * I-Type encoding:
<------> * +------------+------------+--------+----------+----------+
<------> * | imm[31:20] | rs1[19:15] | funct3 | rd[11:7] | opc[6:0] |
<------> * +------------+------------+--------+----------+----------+
<------> *
<------> */
<------>unsigned long offset = got_plt - plt;
<------>u32 hi20 = (offset + 0x800) & 0xfffff000;
<------>u32 lo12 = (offset - hi20);
<------>return (struct plt_entry) {
<------><------>OPC_AUIPC | (REG_T0 << 7) | hi20,
<------><------>OPC_LD | (lo12 << 20) | (REG_T0 << 15) | (REG_T1 << 7),
<------><------>OPC_JALR | (REG_T1 << 15)
<------>};
}
 
static inline int get_got_plt_idx(unsigned long val, const struct mod_section *sec)
{
<------>struct got_entry *got_plt = (struct got_entry *)sec->shdr->sh_addr;
<------>int i;
<------>for (i = 0; i < sec->num_entries; i++) {
<------><------>if (got_plt[i].symbol_addr == val)
<------><------><------>return i;
<------>}
<------>return -1;
}
 
static inline struct plt_entry *get_plt_entry(unsigned long val,
<------><------><------><------><------>      const struct mod_section *sec_plt,
<------><------><------><------><------>      const struct mod_section *sec_got_plt)
{
<------>struct plt_entry *plt = (struct plt_entry *)sec_plt->shdr->sh_addr;
<------>int got_plt_idx = get_got_plt_idx(val, sec_got_plt);
<------>if (got_plt_idx >= 0)
<------><------>return plt + got_plt_idx;
<------>else
<------><------>return NULL;
}
 
#endif /* CONFIG_MODULE_SECTIONS */
 
#endif /* _ASM_RISCV_MODULE_H */