1 /* Kernel module help for SH. 2 3 SHcompact version by Kaz Kojima and Paul Mundt. 4 5 SHmedia bits: 6 7 Copyright 2004 SuperH (UK) Ltd 8 Author: Richard Curnow 9 10 Based on the sh version, and on code from the sh64-specific parts of 11 modutils, originally written by Richard Curnow and Ben Gaster. 12 13 This program is free software; you can redistribute it and/or modify 14 it under the terms of the GNU General Public License as published by 15 the Free Software Foundation; either version 2 of the License, or 16 (at your option) any later version. 17 18 This program is distributed in the hope that it will be useful, 19 but WITHOUT ANY WARRANTY; without even the implied warranty of 20 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 21 GNU General Public License for more details. 22 23 You should have received a copy of the GNU General Public License 24 along with this program; if not, write to the Free Software 25 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 26 */ 27 #include <linux/moduleloader.h> 28 #include <linux/elf.h> 29 #include <linux/vmalloc.h> 30 #include <linux/bug.h> 31 #include <linux/fs.h> 32 #include <linux/string.h> 33 #include <linux/kernel.h> 34 #include <asm/unaligned.h> 35 #include <asm/dwarf.h> 36 37 int apply_relocate_add(Elf32_Shdr *sechdrs, 38 const char *strtab, 39 unsigned int symindex, 40 unsigned int relsec, 41 struct module *me) 42 { 43 unsigned int i; 44 Elf32_Rela *rel = (void *)sechdrs[relsec].sh_addr; 45 Elf32_Sym *sym; 46 Elf32_Addr relocation; 47 uint32_t *location; 48 uint32_t value; 49 50 pr_debug("Applying relocate section %u to %u\n", relsec, 51 sechdrs[relsec].sh_info); 52 for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) { 53 /* This is where to make the change */ 54 location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr 55 + rel[i].r_offset; 56 /* This is the symbol it is referring to. Note that all 57 undefined symbols have been resolved. */ 58 sym = (Elf32_Sym *)sechdrs[symindex].sh_addr 59 + ELF32_R_SYM(rel[i].r_info); 60 relocation = sym->st_value + rel[i].r_addend; 61 62 #ifdef CONFIG_SUPERH64 63 /* For text addresses, bit2 of the st_other field indicates 64 * whether the symbol is SHmedia (1) or SHcompact (0). If 65 * SHmedia, the LSB of the symbol needs to be asserted 66 * for the CPU to be in SHmedia mode when it starts executing 67 * the branch target. */ 68 relocation |= !!(sym->st_other & 4); 69 #endif 70 71 switch (ELF32_R_TYPE(rel[i].r_info)) { 72 case R_SH_NONE: 73 break; 74 case R_SH_DIR32: 75 value = get_unaligned(location); 76 value += relocation; 77 put_unaligned(value, location); 78 break; 79 case R_SH_REL32: 80 relocation = (relocation - (Elf32_Addr) location); 81 value = get_unaligned(location); 82 value += relocation; 83 put_unaligned(value, location); 84 break; 85 case R_SH_IMM_LOW16: 86 *location = (*location & ~0x3fffc00) | 87 ((relocation & 0xffff) << 10); 88 break; 89 case R_SH_IMM_MEDLOW16: 90 *location = (*location & ~0x3fffc00) | 91 (((relocation >> 16) & 0xffff) << 10); 92 break; 93 case R_SH_IMM_LOW16_PCREL: 94 relocation -= (Elf32_Addr) location; 95 *location = (*location & ~0x3fffc00) | 96 ((relocation & 0xffff) << 10); 97 break; 98 case R_SH_IMM_MEDLOW16_PCREL: 99 relocation -= (Elf32_Addr) location; 100 *location = (*location & ~0x3fffc00) | 101 (((relocation >> 16) & 0xffff) << 10); 102 break; 103 default: 104 printk(KERN_ERR "module %s: Unknown relocation: %u\n", 105 me->name, ELF32_R_TYPE(rel[i].r_info)); 106 return -ENOEXEC; 107 } 108 } 109 return 0; 110 } 111 112 int module_finalize(const Elf_Ehdr *hdr, 113 const Elf_Shdr *sechdrs, 114 struct module *me) 115 { 116 int ret = 0; 117 118 ret |= module_dwarf_finalize(hdr, sechdrs, me); 119 120 return ret; 121 } 122 123 void module_arch_cleanup(struct module *mod) 124 { 125 module_dwarf_cleanup(mod); 126 } 127