arch/score/kernel/module.c

   1 /*
   2  * arch/score/kernel/module.c
   3  *
   4  * Score Processor version.
   5  *
   6  * Copyright (C) 2009 Sunplus Core Technology Co., Ltd.
   7  *  Chen Liqin <liqin.chen@sunplusct.com>
   8  *  Lennox Wu <lennox.wu@sunplusct.com>
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, see the file COPYING, or write
  22  * to the Free Software Foundation, Inc.,
  23  * 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  24  */
  25
  26 #include <linux/moduleloader.h>
  27 #include <linux/module.h>
  28 #include <linux/vmalloc.h>
  29
  30 int apply_relocate(Elf_Shdr *sechdrs, const char *strtab,
  31                 unsigned int symindex, unsigned int relindex,
  32                 struct module *me)
  33 {
  34         Elf32_Shdr *symsec = sechdrs + symindex;
  35         Elf32_Shdr *relsec = sechdrs + relindex;
  36         Elf32_Shdr *dstsec = sechdrs + relsec->sh_info;
  37         Elf32_Rel *rel = (void *)relsec->sh_addr;
  38         unsigned int i;
  39
  40         for (i = 0; i < relsec->sh_size / sizeof(Elf32_Rel); i++, rel++) {
  41                 unsigned long loc;
  42                 Elf32_Sym *sym;
  43                 s32 r_offset;
  44
  45                 r_offset = ELF32_R_SYM(rel->r_info);
  46                 if ((r_offset < 0) ||
  47                     (r_offset > (symsec->sh_size / sizeof(Elf32_Sym)))) {
  48                         printk(KERN_ERR "%s: bad relocation, section %d reloc %d\n",
  49                                 me->name, relindex, i);
  50                                 return -ENOEXEC;
  51                 }
  52
  53                 sym = ((Elf32_Sym *)symsec->sh_addr) + r_offset;
  54
  55                 if ((rel->r_offset < 0) ||
  56                     (rel->r_offset > dstsec->sh_size - sizeof(u32))) {
  57                         printk(KERN_ERR "%s: out of bounds relocation, "
  58                                 "section %d reloc %d offset %d size %d\n",
  59                                 me->name, relindex, i, rel->r_offset,
  60                                 dstsec->sh_size);
  61                         return -ENOEXEC;
  62                 }
  63
  64                 loc = dstsec->sh_addr + rel->r_offset;
  65                 switch (ELF32_R_TYPE(rel->r_info)) {
  66                 case R_SCORE_NONE:
  67                         break;
  68                 case R_SCORE_ABS32:
  69                         *(unsigned long *)loc += sym->st_value;
  70                         break;
  71                 case R_SCORE_HI16:
  72                         break;
  73                 case R_SCORE_LO16: {
  74                         unsigned long hi16_offset, offset;
  75                         unsigned long uvalue;
  76                         unsigned long temp, temp_hi;
  77                         temp_hi = *((unsigned long *)loc - 1);
  78                         temp = *(unsigned long *)loc;
  79
  80                         hi16_offset = (((((temp_hi) >> 16) & 0x3) << 15) |
  81                                         ((temp_hi) & 0x7fff)) >> 1;
  82                         offset = ((temp >> 16 & 0x03) << 15) |
  83                                         ((temp & 0x7fff) >> 1);
  84                         offset = (hi16_offset << 16) | (offset & 0xffff);
  85                         uvalue = sym->st_value + offset;
  86                         hi16_offset = (uvalue >> 16) << 1;
  87
  88                         temp_hi = ((temp_hi) & (~(0x37fff))) |
  89                                         (hi16_offset & 0x7fff) |
  90                                         ((hi16_offset << 1) & 0x30000);
  91                         *((unsigned long *)loc - 1) = temp_hi;
  92
  93                         offset = (uvalue & 0xffff) << 1;
  94                         temp = (temp & (~(0x37fff))) | (offset & 0x7fff) |
  95                                 ((offset << 1) & 0x30000);
  96                         *(unsigned long *)loc = temp;
  97                         break;
  98                 }
  99                 case R_SCORE_24: {
 100                         unsigned long hi16_offset, offset;
 101                         unsigned long uvalue;
 102                         unsigned long temp;
 103
 104                         temp = *(unsigned long *)loc;
 105                         offset = (temp & 0x03FF7FFE);
 106                         hi16_offset = (offset & 0xFFFF0000);
 107                         offset = (hi16_offset | ((offset & 0xFFFF) << 1)) >> 2;
 108
 109                         uvalue = (sym->st_value + offset) >> 1;
 110                         uvalue = uvalue & 0x00ffffff;
 111
 112                         temp = (temp & 0xfc008001) |
 113                                 ((uvalue << 2) & 0x3ff0000) |
 114                                 ((uvalue & 0x3fff) << 1);
 115                         *(unsigned long *)loc = temp;
 116                         break;
 117                 }
 118                 default:
 119                         printk(KERN_ERR "%s: unknown relocation: %u\n",
 120                                 me->name, ELF32_R_TYPE(rel->r_info));
 121                         return -ENOEXEC;
 122                 }
 123         }
 124
 125         return 0;
 126 }
 127
 128 int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab,
 129                 unsigned int symindex, unsigned int relsec,
 130                 struct module *me)
 131 {
 132         /* Non-standard return value... most other arch's return -ENOEXEC
 133          * for an unsupported relocation variant
 134          */
 135         return 0;
 136 }
 137
 138 /* Given an address, look for it in the module exception tables. */
 139 const struct exception_table_entry *search_module_dbetables(unsigned long addr)
 140 {
 141         return NULL;
 142 }