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/fs.h> 31 #include <linux/string.h> 32 #include <linux/kernel.h> 33 34 void *module_alloc(unsigned long size) 35 { 36 if (size == 0) 37 return NULL; 38 return vmalloc(size); 39 } 40 41 42 /* Free memory returned from module_alloc */ 43 void module_free(struct module *mod, void *module_region) 44 { 45 vfree(module_region); 46 /* FIXME: If module_region == mod->init_region, trim exception 47 table entries. */ 48 } 49 50 /* We don't need anything special. */ 51 int module_frob_arch_sections(Elf_Ehdr *hdr, 52 Elf_Shdr *sechdrs, 53 char *secstrings, 54 struct module *mod) 55 { 56 return 0; 57 } 58 59 #ifdef CONFIG_SUPERH32 60 #define COPY_UNALIGNED_WORD(sw, tw, align) \ 61 { \ 62 void *__s = &(sw), *__t = &(tw); \ 63 unsigned short *__s2 = __s, *__t2 = __t; \ 64 unsigned char *__s1 = __s, *__t1 = __t; \ 65 switch ((align)) \ 66 { \ 67 case 0: \ 68 *(unsigned long *) __t = *(unsigned long *) __s; \ 69 break; \ 70 case 2: \ 71 *__t2++ = *__s2++; \ 72 *__t2 = *__s2; \ 73 break; \ 74 default: \ 75 *__t1++ = *__s1++; \ 76 *__t1++ = *__s1++; \ 77 *__t1++ = *__s1++; \ 78 *__t1 = *__s1; \ 79 break; \ 80 } \ 81 } 82 #else 83 /* One thing SHmedia doesn't screw up! */ 84 #define COPY_UNALIGNED_WORD(sw, tw, align) { (tw) = (sw); } 85 #endif 86 87 int apply_relocate_add(Elf32_Shdr *sechdrs, 88 const char *strtab, 89 unsigned int symindex, 90 unsigned int relsec, 91 struct module *me) 92 { 93 unsigned int i; 94 Elf32_Rela *rel = (void *)sechdrs[relsec].sh_addr; 95 Elf32_Sym *sym; 96 Elf32_Addr relocation; 97 uint32_t *location; 98 uint32_t value; 99 int align; 100 101 pr_debug("Applying relocate section %u to %u\n", relsec, 102 sechdrs[relsec].sh_info); 103 for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) { 104 /* This is where to make the change */ 105 location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr 106 + rel[i].r_offset; 107 /* This is the symbol it is referring to. Note that all 108 undefined symbols have been resolved. */ 109 sym = (Elf32_Sym *)sechdrs[symindex].sh_addr 110 + ELF32_R_SYM(rel[i].r_info); 111 relocation = sym->st_value + rel[i].r_addend; 112 align = (int)location & 3; 113 114 #ifdef CONFIG_SUPERH64 115 /* For text addresses, bit2 of the st_other field indicates 116 * whether the symbol is SHmedia (1) or SHcompact (0). If 117 * SHmedia, the LSB of the symbol needs to be asserted 118 * for the CPU to be in SHmedia mode when it starts executing 119 * the branch target. */ 120 relocation |= (sym->st_other & 4); 121 #endif 122 123 switch (ELF32_R_TYPE(rel[i].r_info)) { 124 case R_SH_DIR32: 125 COPY_UNALIGNED_WORD (*location, value, align); 126 value += relocation; 127 COPY_UNALIGNED_WORD (value, *location, align); 128 break; 129 case R_SH_REL32: 130 relocation = (relocation - (Elf32_Addr) location); 131 COPY_UNALIGNED_WORD (*location, value, align); 132 value += relocation; 133 COPY_UNALIGNED_WORD (value, *location, align); 134 break; 135 case R_SH_IMM_LOW16: 136 *location = (*location & ~0x3fffc00) | 137 ((relocation & 0xffff) << 10); 138 break; 139 case R_SH_IMM_MEDLOW16: 140 *location = (*location & ~0x3fffc00) | 141 (((relocation >> 16) & 0xffff) << 10); 142 break; 143 case R_SH_IMM_LOW16_PCREL: 144 relocation -= (Elf32_Addr) location; 145 *location = (*location & ~0x3fffc00) | 146 ((relocation & 0xffff) << 10); 147 break; 148 case R_SH_IMM_MEDLOW16_PCREL: 149 relocation -= (Elf32_Addr) location; 150 *location = (*location & ~0x3fffc00) | 151 (((relocation >> 16) & 0xffff) << 10); 152 break; 153 default: 154 printk(KERN_ERR "module %s: Unknown relocation: %u\n", 155 me->name, ELF32_R_TYPE(rel[i].r_info)); 156 return -ENOEXEC; 157 } 158 } 159 return 0; 160 } 161 162 int apply_relocate(Elf32_Shdr *sechdrs, 163 const char *strtab, 164 unsigned int symindex, 165 unsigned int relsec, 166 struct module *me) 167 { 168 printk(KERN_ERR "module %s: REL RELOCATION unsupported\n", 169 me->name); 170 return -ENOEXEC; 171 } 172 173 int module_finalize(const Elf_Ehdr *hdr, 174 const Elf_Shdr *sechdrs, 175 struct module *me) 176 { 177 return 0; 178 } 179 180 void module_arch_cleanup(struct module *mod) 181 { 182 } 183