arch/microblaze/kernel/module.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) 2007-2009 Michal Simek <[email protected]>
   4  * Copyright (C) 2007-2009 PetaLogix
   5  */
   6
   7 #include <linux/export.h>
   8 #include <linux/moduleloader.h>
   9 #include <linux/kernel.h>
  10 #include <linux/elf.h>
  11 #include <linux/vmalloc.h>
  12 #include <linux/fs.h>
  13 #include <linux/string.h>
  14 #include <linux/pgtable.h>
  15
  16 #include <asm/cacheflush.h>
  17
  18 int apply_relocate_add(Elf32_Shdr *sechdrs, const char *strtab,
  19         unsigned int symindex, unsigned int relsec, struct module *module)
  20 {
  21
  22         unsigned int i;
  23         Elf32_Rela *rela = (void *)sechdrs[relsec].sh_addr;
  24         Elf32_Sym *sym;
  25         unsigned long int *location;
  26         unsigned long int value;
  27
  28         pr_debug("Applying add relocation section %u to %u\n",
  29                 relsec, sechdrs[relsec].sh_info);
  30
  31         for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rela); i++) {
  32
  33                 location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr +
  34                                 rela[i].r_offset;
  35                 sym = (Elf32_Sym *)sechdrs[symindex].sh_addr +
  36                         ELF32_R_SYM(rela[i].r_info);
  37                 value = sym->st_value + rela[i].r_addend;
  38
  39                 switch (ELF32_R_TYPE(rela[i].r_info)) {
  40
  41                 /*
  42                  * Be careful! mb-gcc / mb-ld splits the relocs between the
  43                  * text and the reloc table. In general this means we must
  44                  * read the current contents of (*location), add any offset
  45                  * then store the result back in
  46                  */
  47
  48                 case R_MICROBLAZE_32:
  49                         *location = value;
  50                         break;
  51
  52                 case R_MICROBLAZE_64:
  53                         location[0] = (location[0] & 0xFFFF0000) |
  54                                         (value >> 16);
  55                         location[1] = (location[1] & 0xFFFF0000) |
  56                                         (value & 0xFFFF);
  57                         break;
  58
  59                 case R_MICROBLAZE_64_PCREL:
  60                         value -= (unsigned long int)(location) + 4;
  61                         location[0] = (location[0] & 0xFFFF0000) |
  62                                         (value >> 16);
  63                         location[1] = (location[1] & 0xFFFF0000) |
  64                                         (value & 0xFFFF);
  65                         pr_debug("R_MICROBLAZE_64_PCREL (%08lx)\n",
  66                                 value);
  67                         break;
  68
  69                 case R_MICROBLAZE_32_PCREL_LO:
  70                         pr_debug("R_MICROBLAZE_32_PCREL_LO\n");
  71                         break;
  72
  73                 case R_MICROBLAZE_64_NONE:
  74                         pr_debug("R_MICROBLAZE_64_NONE\n");
  75                         break;
  76
  77                 case R_MICROBLAZE_NONE:
  78                         pr_debug("R_MICROBLAZE_NONE\n");
  79                         break;
  80
  81                 default:
  82                         pr_err("module %s: Unknown relocation: %u\n",
  83                                 module->name,
  84                                 ELF32_R_TYPE(rela[i].r_info));
  85                         return -ENOEXEC;
  86                 }
  87         }
  88         return 0;
  89 }
  90
  91 int module_finalize(const Elf32_Ehdr *hdr, const Elf_Shdr *sechdrs,
  92                 struct module *module)
  93 {
  94         flush_dcache();
  95         return 0;
  96 }