LXR linux/arch/microblaze/kernel/module.c

   1/*
   2 * Copyright (C) 2007-2009 Michal Simek <monstr@monstr.eu>
   3 * Copyright (C) 2007-2009 PetaLogix
   4 *
   5 * This program is free software; you can redistribute it and/or modify
   6 * it under the terms of the GNU General Public License version 2 as
   7 * published by the Free Software Foundation.
   8 */
   9
  10#include <linux/export.h>
  11#include <linux/moduleloader.h>
  12#include <linux/kernel.h>
  13#include <linux/elf.h>
  14#include <linux/vmalloc.h>
  15#include <linux/fs.h>
  16#include <linux/string.h>
  17
  18#include <asm/pgtable.h>
  19#include <asm/cacheflush.h>
  20
  21int apply_relocate_add(Elf32_Shdr *sechdrs, const char *strtab,
  22        unsigned int symindex, unsigned int relsec, struct module *module)
  23{
  24
  25        unsigned int i;
  26        Elf32_Rela *rela = (void *)sechdrs[relsec].sh_addr;
  27        Elf32_Sym *sym;
  28        unsigned long int *location;
  29        unsigned long int value;
  30#if __GNUC__ < 4
  31        unsigned long int old_value;
  32#endif
  33
  34        pr_debug("Applying add relocation section %u to %u\n",
  35                relsec, sechdrs[relsec].sh_info);
  36
  37        for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rela); i++) {
  38
  39                location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr +
  40                                rela[i].r_offset;
  41                sym = (Elf32_Sym *)sechdrs[symindex].sh_addr +
  42                        ELF32_R_SYM(rela[i].r_info);
  43                value = sym->st_value + rela[i].r_addend;
  44
  45                switch (ELF32_R_TYPE(rela[i].r_info)) {
  46
  47                /*
  48                 * Be careful! mb-gcc / mb-ld splits the relocs between the
  49                 * text and the reloc table. In general this means we must
  50                 * read the current contents of (*location), add any offset
  51                 * then store the result back in
  52                 */
  53
  54                case R_MICROBLAZE_32:
  55#if __GNUC__ < 4
  56                        old_value = *location;
  57                        *location = value + old_value;
  58
  59                        pr_debug("R_MICROBLAZE_32 (%08lx->%08lx)\n",
  60                                old_value, value);
  61#else
  62                        *location = value;
  63#endif
  64                        break;
  65
  66                case R_MICROBLAZE_64:
  67#if __GNUC__ < 4
  68                        /* Split relocs only required/used pre gcc4.1.1 */
  69                        old_value = ((location[0] & 0x0000FFFF) << 16) |
  70                                        (location[1] & 0x0000FFFF);
  71                        value += old_value;
  72#endif
  73                        location[0] = (location[0] & 0xFFFF0000) |
  74                                        (value >> 16);
  75                        location[1] = (location[1] & 0xFFFF0000) |
  76                                        (value & 0xFFFF);
  77#if __GNUC__ < 4
  78                        pr_debug("R_MICROBLAZE_64 (%08lx->%08lx)\n",
  79                                old_value, value);
  80#endif
  81                        break;
  82
  83                case R_MICROBLAZE_64_PCREL:
  84#if __GNUC__ < 4
  85                        old_value = (location[0] & 0xFFFF) << 16 |
  86                                (location[1] & 0xFFFF);
  87                        value -= old_value;
  88#endif
  89                        value -= (unsigned long int)(location) + 4;
  90                        location[0] = (location[0] & 0xFFFF0000) |
  91                                        (value >> 16);
  92                        location[1] = (location[1] & 0xFFFF0000) |
  93                                        (value & 0xFFFF);
  94                        pr_debug("R_MICROBLAZE_64_PCREL (%08lx)\n",
  95                                value);
  96                        break;
  97
  98                case R_MICROBLAZE_32_PCREL_LO:
  99                        pr_debug("R_MICROBLAZE_32_PCREL_LO\n");
 100                        break;
 101
 102                case R_MICROBLAZE_64_NONE:
 103                        pr_debug("R_MICROBLAZE_64_NONE\n");
 104                        break;
 105
 106                case R_MICROBLAZE_NONE:
 107                        pr_debug("R_MICROBLAZE_NONE\n");
 108                        break;
 109
 110                default:
 111                        pr_err("module %s: Unknown relocation: %u\n",
 112                                module->name,
 113                                ELF32_R_TYPE(rela[i].r_info));
 114                        return -ENOEXEC;
 115                }
 116        }
 117        return 0;
 118}
 119
 120int module_finalize(const Elf32_Ehdr *hdr, const Elf_Shdr *sechdrs,
 121                struct module *module)
 122{
 123        flush_dcache();
 124        return 0;
 125}
 126