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