1// SPDX-License-Identifier: GPL-2.0+
2/*  Kernel module help for SH.
3
4    SHcompact version by Kaz Kojima and Paul Mundt.
5
6    SHmedia bits:
7
8	Copyright 2004 SuperH (UK) Ltd
9	Author: Richard Curnow
10
11	Based on the sh version, and on code from the sh64-specific parts of
12	modutils, originally written by Richard Curnow and Ben Gaster.
13*/
14#include <linux/moduleloader.h>
15#include <linux/elf.h>
16#include <linux/vmalloc.h>
17#include <linux/bug.h>
18#include <linux/fs.h>
19#include <linux/string.h>
20#include <linux/kernel.h>
21#include <asm/unaligned.h>
22#include <asm/dwarf.h>
23
24int apply_relocate_add(Elf32_Shdr *sechdrs,
25		   const char *strtab,
26		   unsigned int symindex,
27		   unsigned int relsec,
28		   struct module *me)
29{
30	unsigned int i;
31	Elf32_Rela *rel = (void *)sechdrs[relsec].sh_addr;
32	Elf32_Sym *sym;
33	Elf32_Addr relocation;
34	uint32_t *location;
35	uint32_t value;
36
37	pr_debug("Applying relocate section %u to %u\n", relsec,
38		 sechdrs[relsec].sh_info);
39	for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
40		/* This is where to make the change */
41		location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr
42			+ rel[i].r_offset;
43		/* This is the symbol it is referring to.  Note that all
44		   undefined symbols have been resolved.  */
45		sym = (Elf32_Sym *)sechdrs[symindex].sh_addr
46			+ ELF32_R_SYM(rel[i].r_info);
47		relocation = sym->st_value + rel[i].r_addend;
48
49		switch (ELF32_R_TYPE(rel[i].r_info)) {
50		case R_SH_NONE:
51			break;
52		case R_SH_DIR32:
53			value = get_unaligned(location);
54			value += relocation;
55			put_unaligned(value, location);
56			break;
57		case R_SH_REL32:
58			relocation = (relocation - (Elf32_Addr) location);
59			value = get_unaligned(location);
60			value += relocation;
61			put_unaligned(value, location);
62			break;
63		case R_SH_IMM_LOW16:
64			*location = (*location & ~0x3fffc00) |
65				((relocation & 0xffff) << 10);
66			break;
67		case R_SH_IMM_MEDLOW16:
68			*location = (*location & ~0x3fffc00) |
69				(((relocation >> 16) & 0xffff) << 10);
70			break;
71		case R_SH_IMM_LOW16_PCREL:
72			relocation -= (Elf32_Addr) location;
73			*location = (*location & ~0x3fffc00) |
74				((relocation & 0xffff) << 10);
75			break;
76		case R_SH_IMM_MEDLOW16_PCREL:
77			relocation -= (Elf32_Addr) location;
78			*location = (*location & ~0x3fffc00) |
79				(((relocation >> 16) & 0xffff) << 10);
80			break;
81		default:
82			printk(KERN_ERR "module %s: Unknown relocation: %u\n",
83			       me->name, ELF32_R_TYPE(rel[i].r_info));
84			return -ENOEXEC;
85		}
86	}
87	return 0;
88}
89
90int module_finalize(const Elf_Ehdr *hdr,
91		    const Elf_Shdr *sechdrs,
92		    struct module *me)
93{
94	int ret = 0;
95
96	ret |= module_dwarf_finalize(hdr, sechdrs, me);
97
98	return ret;
99}
100
101void module_arch_cleanup(struct module *mod)
102{
103	module_dwarf_cleanup(mod);
104}
105