microblaze: Fix module loading on system with WB cache
[sfrench/cifs-2.6.git] / arch / microblaze / kernel / module.c
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/module.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
21 void *module_alloc(unsigned long size)
22 {
23         void *ret;
24         ret = (size == 0) ? NULL : vmalloc(size);
25         pr_debug("module_alloc (%08lx@%08lx)\n", size, (unsigned long int)ret);
26         return ret;
27 }
28
29 void module_free(struct module *module, void *region)
30 {
31         pr_debug("module_free(%s,%08lx)\n", module->name,
32                                         (unsigned long)region);
33         vfree(region);
34 }
35
36 int module_frob_arch_sections(Elf_Ehdr *hdr,
37                                 Elf_Shdr *sechdrs,
38                                 char *secstrings,
39                                 struct module *mod)
40 {
41         return 0;
42 }
43
44 int apply_relocate(Elf32_Shdr *sechdrs, const char *strtab,
45         unsigned int symindex, unsigned int relsec, struct module *module)
46 {
47         printk(KERN_ERR "module %s: ADD RELOCATION unsupported\n",
48                 module->name);
49         return -ENOEXEC;
50 }
51
52 int apply_relocate_add(Elf32_Shdr *sechdrs, const char *strtab,
53         unsigned int symindex, unsigned int relsec, struct module *module)
54 {
55
56         unsigned int i;
57         Elf32_Rela *rela = (void *)sechdrs[relsec].sh_addr;
58         Elf32_Sym *sym;
59         unsigned long int *location;
60         unsigned long int value;
61 #if __GNUC__ < 4
62         unsigned long int old_value;
63 #endif
64
65         pr_debug("Applying add relocation section %u to %u\n",
66                 relsec, sechdrs[relsec].sh_info);
67
68         for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rela); i++) {
69
70                 location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr +
71                                 rela[i].r_offset;
72                 sym = (Elf32_Sym *)sechdrs[symindex].sh_addr +
73                         ELF32_R_SYM(rela[i].r_info);
74                 value = sym->st_value + rela[i].r_addend;
75
76                 switch (ELF32_R_TYPE(rela[i].r_info)) {
77
78                 /*
79                  * Be careful! mb-gcc / mb-ld splits the relocs between the
80                  * text and the reloc table. In general this means we must
81                  * read the current contents of (*location), add any offset
82                  * then store the result back in
83                  */
84
85                 case R_MICROBLAZE_32:
86 #if __GNUC__ < 4
87                         old_value = *location;
88                         *location = value + old_value;
89
90                         pr_debug("R_MICROBLAZE_32 (%08lx->%08lx)\n",
91                                 old_value, value);
92 #else
93                         *location = value;
94 #endif
95                         break;
96
97                 case R_MICROBLAZE_64:
98 #if __GNUC__ < 4
99                         /* Split relocs only required/used pre gcc4.1.1 */
100                         old_value = ((location[0] & 0x0000FFFF) << 16) |
101                                         (location[1] & 0x0000FFFF);
102                         value += old_value;
103 #endif
104                         location[0] = (location[0] & 0xFFFF0000) |
105                                         (value >> 16);
106                         location[1] = (location[1] & 0xFFFF0000) |
107                                         (value & 0xFFFF);
108 #if __GNUC__ < 4
109                         pr_debug("R_MICROBLAZE_64 (%08lx->%08lx)\n",
110                                 old_value, value);
111 #endif
112                         break;
113
114                 case R_MICROBLAZE_64_PCREL:
115 #if __GNUC__ < 4
116                         old_value = (location[0] & 0xFFFF) << 16 |
117                                 (location[1] & 0xFFFF);
118                         value -= old_value;
119 #endif
120                         value -= (unsigned long int)(location) + 4;
121                         location[0] = (location[0] & 0xFFFF0000) |
122                                         (value >> 16);
123                         location[1] = (location[1] & 0xFFFF0000) |
124                                         (value & 0xFFFF);
125                         pr_debug("R_MICROBLAZE_64_PCREL (%08lx)\n",
126                                 value);
127                         break;
128
129                 case R_MICROBLAZE_32_PCREL_LO:
130                         pr_debug("R_MICROBLAZE_32_PCREL_LO\n");
131                         break;
132
133                 case R_MICROBLAZE_64_NONE:
134                         pr_debug("R_MICROBLAZE_NONE\n");
135                         break;
136
137                 case R_MICROBLAZE_NONE:
138                         pr_debug("R_MICROBLAZE_NONE\n");
139                         break;
140
141                 default:
142                         printk(KERN_ERR "module %s: "
143                                 "Unknown relocation: %u\n",
144                                 module->name,
145                                 ELF32_R_TYPE(rela[i].r_info));
146                         return -ENOEXEC;
147                 }
148         }
149         return 0;
150 }
151
152 int module_finalize(const Elf32_Ehdr *hdr, const Elf_Shdr *sechdrs,
153                 struct module *module)
154 {
155         flush_dcache();
156         return 0;
157 }
158
159 void module_arch_cleanup(struct module *mod)
160 {
161 }