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 void *module_alloc(unsigned long size) 38 { 39 if (size == 0) 40 return NULL; 41 42 return vmalloc_exec(size); 43 } 44 45 46 /* Free memory returned from module_alloc */ 47 void module_free(struct module *mod, void *module_region) 48 { 49 vfree(module_region); 50 } 51 52 /* We don't need anything special. */ 53 int module_frob_arch_sections(Elf_Ehdr *hdr, 54 Elf_Shdr *sechdrs, 55 char *secstrings, 56 struct module *mod) 57 { 58 return 0; 59 } 60 61 int apply_relocate_add(Elf32_Shdr *sechdrs, 62 const char *strtab, 63 unsigned int symindex, 64 unsigned int relsec, 65 struct module *me) 66 { 67 unsigned int i; 68 Elf32_Rela *rel = (void *)sechdrs[relsec].sh_addr; 69 Elf32_Sym *sym; 70 Elf32_Addr relocation; 71 uint32_t *location; 72 uint32_t value; 73 74 pr_debug("Applying relocate section %u to %u\n", relsec, 75 sechdrs[relsec].sh_info); 76 for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) { 77 /* This is where to make the change */ 78 location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr 79 + rel[i].r_offset; 80 /* This is the symbol it is referring to. Note that all 81 undefined symbols have been resolved. */ 82 sym = (Elf32_Sym *)sechdrs[symindex].sh_addr 83 + ELF32_R_SYM(rel[i].r_info); 84 relocation = sym->st_value + rel[i].r_addend; 85 86 #ifdef CONFIG_SUPERH64 87 /* For text addresses, bit2 of the st_other field indicates 88 * whether the symbol is SHmedia (1) or SHcompact (0). If 89 * SHmedia, the LSB of the symbol needs to be asserted 90 * for the CPU to be in SHmedia mode when it starts executing 91 * the branch target. */ 92 relocation |= !!(sym->st_other & 4); 93 #endif 94 95 switch (ELF32_R_TYPE(rel[i].r_info)) { 96 case R_SH_NONE: 97 break; 98 case R_SH_DIR32: 99 value = get_unaligned(location); 100 value += relocation; 101 put_unaligned(value, location); 102 break; 103 case R_SH_REL32: 104 relocation = (relocation - (Elf32_Addr) location); 105 value = get_unaligned(location); 106 value += relocation; 107 put_unaligned(value, location); 108 break; 109 case R_SH_IMM_LOW16: 110 *location = (*location & ~0x3fffc00) | 111 ((relocation & 0xffff) << 10); 112 break; 113 case R_SH_IMM_MEDLOW16: 114 *location = (*location & ~0x3fffc00) | 115 (((relocation >> 16) & 0xffff) << 10); 116 break; 117 case R_SH_IMM_LOW16_PCREL: 118 relocation -= (Elf32_Addr) location; 119 *location = (*location & ~0x3fffc00) | 120 ((relocation & 0xffff) << 10); 121 break; 122 case R_SH_IMM_MEDLOW16_PCREL: 123 relocation -= (Elf32_Addr) location; 124 *location = (*location & ~0x3fffc00) | 125 (((relocation >> 16) & 0xffff) << 10); 126 break; 127 default: 128 printk(KERN_ERR "module %s: Unknown relocation: %u\n", 129 me->name, ELF32_R_TYPE(rel[i].r_info)); 130 return -ENOEXEC; 131 } 132 } 133 return 0; 134 } 135 136 int apply_relocate(Elf32_Shdr *sechdrs, 137 const char *strtab, 138 unsigned int symindex, 139 unsigned int relsec, 140 struct module *me) 141 { 142 printk(KERN_ERR "module %s: REL RELOCATION unsupported\n", 143 me->name); 144 return -ENOEXEC; 145 } 146 147 int module_finalize(const Elf_Ehdr *hdr, 148 const Elf_Shdr *sechdrs, 149 struct module *me) 150 { 151 int ret = 0; 152 153 ret |= module_dwarf_finalize(hdr, sechdrs, me); 154 155 return ret; 156 } 157 158 void module_arch_cleanup(struct module *mod) 159 { 160 module_dwarf_cleanup(mod); 161 } 162