1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * OpenRISC module.c 4 * 5 * Linux architectural port borrowing liberally from similar works of 6 * others. All original copyrights apply as per the original source 7 * declaration. 8 * 9 * Modifications for the OpenRISC architecture: 10 * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se> 11 */ 12 13 #include <linux/moduleloader.h> 14 #include <linux/elf.h> 15 16 int apply_relocate_add(Elf32_Shdr *sechdrs, 17 const char *strtab, 18 unsigned int symindex, 19 unsigned int relsec, 20 struct module *me) 21 { 22 unsigned int i; 23 Elf32_Rela *rel = (void *)sechdrs[relsec].sh_addr; 24 Elf32_Sym *sym; 25 uint32_t *location; 26 uint32_t value; 27 28 pr_debug("Applying relocate section %u to %u\n", relsec, 29 sechdrs[relsec].sh_info); 30 for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) { 31 /* This is where to make the change */ 32 location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr 33 + rel[i].r_offset; 34 35 /* This is the symbol it is referring to. Note that all 36 undefined symbols have been resolved. */ 37 sym = (Elf32_Sym *)sechdrs[symindex].sh_addr 38 + ELF32_R_SYM(rel[i].r_info); 39 value = sym->st_value + rel[i].r_addend; 40 41 switch (ELF32_R_TYPE(rel[i].r_info)) { 42 case R_OR1K_32: 43 *location = value; 44 break; 45 case R_OR1K_LO_16_IN_INSN: 46 *((uint16_t *)location + 1) = value; 47 break; 48 case R_OR1K_HI_16_IN_INSN: 49 *((uint16_t *)location + 1) = value >> 16; 50 break; 51 case R_OR1K_INSN_REL_26: 52 value -= (uint32_t)location; 53 value >>= 2; 54 value &= 0x03ffffff; 55 value |= *location & 0xfc000000; 56 *location = value; 57 break; 58 case R_OR1K_AHI16: 59 /* Adjust the operand to match with a signed LO16. */ 60 value += 0x8000; 61 *((uint16_t *)location + 1) = value >> 16; 62 break; 63 case R_OR1K_SLO16: 64 /* Split value lower 16-bits. */ 65 value = ((value & 0xf800) << 10) | (value & 0x7ff); 66 *location = (*location & ~0x3e007ff) | value; 67 break; 68 default: 69 pr_err("module %s: Unknown relocation: %u\n", 70 me->name, ELF32_R_TYPE(rel[i].r_info)); 71 break; 72 } 73 } 74 75 return 0; 76 } 77