1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (C) 2007-2009 Michal Simek <monstr@monstr.eu>
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
18int 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
91int module_finalize(const Elf32_Ehdr *hdr, const Elf_Shdr *sechdrs,
92 struct module *module)
93{
94 flush_dcache();
95 return 0;
96}
97

source code of linux/arch/microblaze/kernel/module.c