1/*  Kernel module help for SH.
2
3    SHcompact version by Kaz Kojima and Paul Mundt.
4
5    SHmedia bits:
6
7	Copyright 2004 SuperH (UK) Ltd
8	Author: Richard Curnow
9
10	Based on the sh version, and on code from the sh64-specific parts of
11	modutils, originally written by Richard Curnow and Ben Gaster.
12
13    This program is free software; you can redistribute it and/or modify
14    it under the terms of the GNU General Public License as published by
15    the Free Software Foundation; either version 2 of the License, or
16    (at your option) any later version.
17
18    This program is distributed in the hope that it will be useful,
19    but WITHOUT ANY WARRANTY; without even the implied warranty of
20    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
21    GNU General Public License for more details.
22
23    You should have received a copy of the GNU General Public License
24    along with this program; if not, write to the Free Software
25    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
26*/
27#include <linux/moduleloader.h>
28#include <linux/elf.h>
29#include <linux/vmalloc.h>
30#include <linux/bug.h>
31#include <linux/fs.h>
32#include <linux/string.h>
33#include <linux/kernel.h>
34#include <asm/unaligned.h>
35#include <asm/dwarf.h>
36
37int apply_relocate_add(Elf32_Shdr *sechdrs,
38		   const char *strtab,
39		   unsigned int symindex,
40		   unsigned int relsec,
41		   struct module *me)
42{
43	unsigned int i;
44	Elf32_Rela *rel = (void *)sechdrs[relsec].sh_addr;
45	Elf32_Sym *sym;
46	Elf32_Addr relocation;
47	uint32_t *location;
48	uint32_t value;
49
50	pr_debug("Applying relocate section %u to %u\n", relsec,
51		 sechdrs[relsec].sh_info);
52	for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
53		/* This is where to make the change */
54		location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr
55			+ rel[i].r_offset;
56		/* This is the symbol it is referring to.  Note that all
57		   undefined symbols have been resolved.  */
58		sym = (Elf32_Sym *)sechdrs[symindex].sh_addr
59			+ ELF32_R_SYM(rel[i].r_info);
60		relocation = sym->st_value + rel[i].r_addend;
61
62#ifdef CONFIG_SUPERH64
63		/* For text addresses, bit2 of the st_other field indicates
64		 * whether the symbol is SHmedia (1) or SHcompact (0).  If
65		 * SHmedia, the LSB of the symbol needs to be asserted
66		 * for the CPU to be in SHmedia mode when it starts executing
67		 * the branch target. */
68		relocation |= !!(sym->st_other & 4);
69#endif
70
71		switch (ELF32_R_TYPE(rel[i].r_info)) {
72		case R_SH_NONE:
73			break;
74		case R_SH_DIR32:
75			value = get_unaligned(location);
76			value += relocation;
77			put_unaligned(value, location);
78			break;
79		case R_SH_REL32:
80			relocation = (relocation - (Elf32_Addr) location);
81			value = get_unaligned(location);
82			value += relocation;
83			put_unaligned(value, location);
84			break;
85		case R_SH_IMM_LOW16:
86			*location = (*location & ~0x3fffc00) |
87				((relocation & 0xffff) << 10);
88			break;
89		case R_SH_IMM_MEDLOW16:
90			*location = (*location & ~0x3fffc00) |
91				(((relocation >> 16) & 0xffff) << 10);
92			break;
93		case R_SH_IMM_LOW16_PCREL:
94			relocation -= (Elf32_Addr) location;
95			*location = (*location & ~0x3fffc00) |
96				((relocation & 0xffff) << 10);
97			break;
98		case R_SH_IMM_MEDLOW16_PCREL:
99			relocation -= (Elf32_Addr) location;
100			*location = (*location & ~0x3fffc00) |
101				(((relocation >> 16) & 0xffff) << 10);
102			break;
103		default:
104			printk(KERN_ERR "module %s: Unknown relocation: %u\n",
105			       me->name, ELF32_R_TYPE(rel[i].r_info));
106			return -ENOEXEC;
107		}
108	}
109	return 0;
110}
111
112int module_finalize(const Elf_Ehdr *hdr,
113		    const Elf_Shdr *sechdrs,
114		    struct module *me)
115{
116	int ret = 0;
117
118	ret |= module_dwarf_finalize(hdr, sechdrs, me);
119
120	return ret;
121}
122
123void module_arch_cleanup(struct module *mod)
124{
125	module_dwarf_cleanup(mod);
126}
127