/* 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>#include <linux/elf.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_SECTIONSstruct 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 */ 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_RISCV_MODULE_H */