Merge git://git.linux-nfs.org/pub/linux/nfs-2.6
[linux-2.6] / arch / blackfin / kernel / module.c
1 /*
2  * File:         arch/blackfin/kernel/module.c
3  * Based on:
4  * Author:
5  *
6  * Created:
7  * Description:
8  *
9  * Modified:
10  *               Copyright 2004-2006 Analog Devices Inc.
11  *
12  * Bugs:         Enter bugs at http://blackfin.uclinux.org/
13  *
14  * This program is free software; you can redistribute it and/or modify
15  * it under the terms of the GNU General Public License as published by
16  * the Free Software Foundation; either version 2 of the License, or
17  * (at your option) any later version.
18  *
19  * This program is distributed in the hope that it will be useful,
20  * but WITHOUT ANY WARRANTY; without even the implied warranty of
21  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
22  * GNU General Public License for more details.
23  *
24  * You should have received a copy of the GNU General Public License
25  * along with this program; if not, see the file COPYING, or write
26  * to the Free Software Foundation, Inc.,
27  * 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
28  */
29
30
31 #include <linux/moduleloader.h>
32 #include <linux/elf.h>
33 #include <linux/vmalloc.h>
34 #include <linux/fs.h>
35 #include <linux/string.h>
36 #include <linux/kernel.h>
37 #include <asm/dma.h>
38 #include <asm/cacheflush.h>
39
40 /*
41  * handle arithmetic relocations.
42  * See binutils/bfd/elf32-bfin.c for more details
43  */
44 #define RELOC_STACK_SIZE 100
45 static uint32_t reloc_stack[RELOC_STACK_SIZE];
46 static unsigned int reloc_stack_tos;
47
48 #define is_reloc_stack_empty() ((reloc_stack_tos > 0)?0:1)
49
50 static void reloc_stack_push(uint32_t value)
51 {
52         reloc_stack[reloc_stack_tos++] = value;
53 }
54
55 static uint32_t reloc_stack_pop(void)
56 {
57         return reloc_stack[--reloc_stack_tos];
58 }
59
60 static uint32_t reloc_stack_operate(unsigned int oper, struct module *mod)
61 {
62         uint32_t value;
63
64         switch (oper) {
65         case R_add:
66                 value = reloc_stack[reloc_stack_tos - 2] +
67                         reloc_stack[reloc_stack_tos - 1];
68                 reloc_stack_tos -= 2;
69                 break;
70         case R_sub:
71                 value = reloc_stack[reloc_stack_tos - 2] -
72                         reloc_stack[reloc_stack_tos - 1];
73                 reloc_stack_tos -= 2;
74                 break;
75         case R_mult:
76                 value = reloc_stack[reloc_stack_tos - 2] *
77                         reloc_stack[reloc_stack_tos - 1];
78                 reloc_stack_tos -= 2;
79                 break;
80         case R_div:
81                 value = reloc_stack[reloc_stack_tos - 2] /
82                         reloc_stack[reloc_stack_tos - 1];
83                 reloc_stack_tos -= 2;
84                 break;
85         case R_mod:
86                 value = reloc_stack[reloc_stack_tos - 2] %
87                         reloc_stack[reloc_stack_tos - 1];
88                 reloc_stack_tos -= 2;
89                 break;
90         case R_lshift:
91                 value = reloc_stack[reloc_stack_tos - 2] <<
92                         reloc_stack[reloc_stack_tos - 1];
93                 reloc_stack_tos -= 2;
94                 break;
95         case R_rshift:
96                 value = reloc_stack[reloc_stack_tos - 2] >>
97                         reloc_stack[reloc_stack_tos - 1];
98                 reloc_stack_tos -= 2;
99                 break;
100         case R_and:
101                 value = reloc_stack[reloc_stack_tos - 2] &
102                         reloc_stack[reloc_stack_tos - 1];
103                 reloc_stack_tos -= 2;
104                 break;
105         case R_or:
106                 value = reloc_stack[reloc_stack_tos - 2] |
107                         reloc_stack[reloc_stack_tos - 1];
108                 reloc_stack_tos -= 2;
109                 break;
110         case R_xor:
111                 value = reloc_stack[reloc_stack_tos - 2] ^
112                         reloc_stack[reloc_stack_tos - 1];
113                 reloc_stack_tos -= 2;
114                 break;
115         case R_land:
116                 value = reloc_stack[reloc_stack_tos - 2] &&
117                         reloc_stack[reloc_stack_tos - 1];
118                 reloc_stack_tos -= 2;
119                 break;
120         case R_lor:
121                 value = reloc_stack[reloc_stack_tos - 2] ||
122                         reloc_stack[reloc_stack_tos - 1];
123                 reloc_stack_tos -= 2;
124                 break;
125         case R_neg:
126                 value = -reloc_stack[reloc_stack_tos - 1];
127                 reloc_stack_tos--;
128                 break;
129         case R_comp:
130                 value = ~reloc_stack[reloc_stack_tos - 1];
131                 reloc_stack_tos -= 1;
132                 break;
133         default:
134                 printk(KERN_WARNING "module %s: unhandled reloction\n",
135                                 mod->name);
136                 return 0;
137         }
138
139         /* now push the new value back on stack */
140         reloc_stack_push(value);
141
142         return value;
143 }
144
145 void *module_alloc(unsigned long size)
146 {
147         if (size == 0)
148                 return NULL;
149         return vmalloc(size);
150 }
151
152 /* Free memory returned from module_alloc */
153 void module_free(struct module *mod, void *module_region)
154 {
155         vfree(module_region);
156 }
157
158 /* Transfer the section to the L1 memory */
159 int
160 module_frob_arch_sections(Elf_Ehdr * hdr, Elf_Shdr * sechdrs,
161                           char *secstrings, struct module *mod)
162 {
163         Elf_Shdr *s, *sechdrs_end = sechdrs + hdr->e_shnum;
164         void *dest = NULL;
165
166         for (s = sechdrs; s < sechdrs_end; ++s) {
167                 if ((strcmp(".l1.text", secstrings + s->sh_name) == 0) ||
168                     ((strcmp(".text", secstrings + s->sh_name) == 0) &&
169                      (hdr->e_flags & FLG_CODE_IN_L1) && (s->sh_size > 0))) {
170                         mod->arch.text_l1 = s;
171                         dest = l1_inst_sram_alloc(s->sh_size);
172                         if (dest == NULL) {
173                                 printk(KERN_ERR
174                                        "module %s: L1 instruction memory allocation failed\n",
175                                        mod->name);
176                                 return -1;
177                         }
178                         dma_memcpy(dest, (void *)s->sh_addr, s->sh_size);
179                         s->sh_flags &= ~SHF_ALLOC;
180                         s->sh_addr = (unsigned long)dest;
181                 }
182                 if ((strcmp(".l1.data", secstrings + s->sh_name) == 0) ||
183                     ((strcmp(".data", secstrings + s->sh_name) == 0) &&
184                      (hdr->e_flags & FLG_DATA_IN_L1) && (s->sh_size > 0))) {
185                         mod->arch.data_a_l1 = s;
186                         dest = l1_data_sram_alloc(s->sh_size);
187                         if (dest == NULL) {
188                                 printk(KERN_ERR
189                                         "module %s: L1 data memory allocation failed\n",
190                                         mod->name);
191                                 return -1;
192                         }
193                         memcpy(dest, (void *)s->sh_addr, s->sh_size);
194                         s->sh_flags &= ~SHF_ALLOC;
195                         s->sh_addr = (unsigned long)dest;
196                 }
197                 if (strcmp(".l1.bss", secstrings + s->sh_name) == 0 ||
198                     ((strcmp(".bss", secstrings + s->sh_name) == 0) &&
199                      (hdr->e_flags & FLG_DATA_IN_L1) && (s->sh_size > 0))) {
200                         mod->arch.bss_a_l1 = s;
201                         dest = l1_data_sram_alloc(s->sh_size);
202                         if (dest == NULL) {
203                                 printk(KERN_ERR
204                                         "module %s: L1 data memory allocation failed\n",
205                                         mod->name);
206                                 return -1;
207                         }
208                         memset(dest, 0, s->sh_size);
209                         s->sh_flags &= ~SHF_ALLOC;
210                         s->sh_addr = (unsigned long)dest;
211                 }
212                 if (strcmp(".l1.data.B", secstrings + s->sh_name) == 0) {
213                         mod->arch.data_b_l1 = s;
214                         dest = l1_data_B_sram_alloc(s->sh_size);
215                         if (dest == NULL) {
216                                 printk(KERN_ERR
217                                         "module %s: L1 data memory allocation failed\n",
218                                         mod->name);
219                                 return -1;
220                         }
221                         memcpy(dest, (void *)s->sh_addr, s->sh_size);
222                         s->sh_flags &= ~SHF_ALLOC;
223                         s->sh_addr = (unsigned long)dest;
224                 }
225                 if (strcmp(".l1.bss.B", secstrings + s->sh_name) == 0) {
226                         mod->arch.bss_b_l1 = s;
227                         dest = l1_data_B_sram_alloc(s->sh_size);
228                         if (dest == NULL) {
229                                 printk(KERN_ERR
230                                         "module %s: L1 data memory allocation failed\n",
231                                         mod->name);
232                                 return -1;
233                         }
234                         memset(dest, 0, s->sh_size);
235                         s->sh_flags &= ~SHF_ALLOC;
236                         s->sh_addr = (unsigned long)dest;
237                 }
238         }
239         return 0;
240 }
241
242 int
243 apply_relocate(Elf_Shdr * sechdrs, const char *strtab,
244                unsigned int symindex, unsigned int relsec, struct module *me)
245 {
246         printk(KERN_ERR "module %s: .rel unsupported\n", me->name);
247         return -ENOEXEC;
248 }
249
250 /*************************************************************************/
251 /* FUNCTION : apply_relocate_add                                         */
252 /* ABSTRACT : Blackfin specific relocation handling for the loadable     */
253 /*            modules. Modules are expected to be .o files.              */
254 /*            Arithmetic relocations are handled.                        */
255 /*            We do not expect LSETUP to be split and hence is not       */
256 /*            handled.                                                   */
257 /*            R_byte and R_byte2 are also not handled as the gas         */
258 /*            does not generate it.                                      */
259 /*************************************************************************/
260 int
261 apply_relocate_add(Elf_Shdr * sechdrs, const char *strtab,
262                    unsigned int symindex, unsigned int relsec,
263                    struct module *mod)
264 {
265         unsigned int i;
266         unsigned short tmp;
267         Elf32_Rela *rel = (void *)sechdrs[relsec].sh_addr;
268         Elf32_Sym *sym;
269         uint32_t *location32;
270         uint16_t *location16;
271         uint32_t value;
272
273         pr_debug("Applying relocate section %u to %u\n", relsec,
274                sechdrs[relsec].sh_info);
275         for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
276                 /* This is where to make the change */
277                 location16 =
278                     (uint16_t *) (sechdrs[sechdrs[relsec].sh_info].sh_addr +
279                                   rel[i].r_offset);
280                 location32 = (uint32_t *) location16;
281                 /* This is the symbol it is referring to. Note that all
282                    undefined symbols have been resolved. */
283                 sym = (Elf32_Sym *) sechdrs[symindex].sh_addr
284                     + ELF32_R_SYM(rel[i].r_info);
285                 if (is_reloc_stack_empty()) {
286                         value = sym->st_value;
287                 } else {
288                         value = reloc_stack_pop();
289                 }
290                 value += rel[i].r_addend;
291                 pr_debug("location is %x, value is %x type is %d \n",
292                          (unsigned int) location32, value,
293                          ELF32_R_TYPE(rel[i].r_info));
294
295                 switch (ELF32_R_TYPE(rel[i].r_info)) {
296
297                 case R_pcrel24:
298                 case R_pcrel24_jump_l:
299                         /* Add the value, subtract its postition */
300                         location16 =
301                             (uint16_t *) (sechdrs[sechdrs[relsec].sh_info].
302                                           sh_addr + rel[i].r_offset - 2);
303                         location32 = (uint32_t *) location16;
304                         value -= (uint32_t) location32;
305                         value >>= 1;
306                         pr_debug("value is %x, before %x-%x after %x-%x\n", value,
307                                *location16, *(location16 + 1),
308                                (*location16 & 0xff00) | (value >> 16 & 0x00ff),
309                                value & 0xffff);
310                         *location16 =
311                             (*location16 & 0xff00) | (value >> 16 & 0x00ff);
312                         *(location16 + 1) = value & 0xffff;
313                         break;
314                 case R_pcrel12_jump:
315                 case R_pcrel12_jump_s:
316                         value -= (uint32_t) location32;
317                         value >>= 1;
318                         *location16 = (value & 0xfff);
319                         break;
320                 case R_pcrel10:
321                         value -= (uint32_t) location32;
322                         value >>= 1;
323                         *location16 = (value & 0x3ff);
324                         break;
325                 case R_luimm16:
326                         pr_debug("before %x after %x\n", *location16,
327                                        (value & 0xffff));
328                         tmp = (value & 0xffff);
329                         if ((unsigned long)location16 >= L1_CODE_START) {
330                                 dma_memcpy(location16, &tmp, 2);
331                         } else
332                                 *location16 = tmp;
333                         break;
334                 case R_huimm16:
335                         pr_debug("before %x after %x\n", *location16,
336                                        ((value >> 16) & 0xffff));
337                         tmp = ((value >> 16) & 0xffff);
338                         if ((unsigned long)location16 >= L1_CODE_START) {
339                                 dma_memcpy(location16, &tmp, 2);
340                         } else
341                                 *location16 = tmp;
342                         break;
343                 case R_rimm16:
344                         *location16 = (value & 0xffff);
345                         break;
346                 case R_byte4_data:
347                         pr_debug("before %x after %x\n", *location32, value);
348                         *location32 = value;
349                         break;
350                 case R_push:
351                         reloc_stack_push(value);
352                         break;
353                 case R_const:
354                         reloc_stack_push(rel[i].r_addend);
355                         break;
356                 case R_add:
357                 case R_sub:
358                 case R_mult:
359                 case R_div:
360                 case R_mod:
361                 case R_lshift:
362                 case R_rshift:
363                 case R_and:
364                 case R_or:
365                 case R_xor:
366                 case R_land:
367                 case R_lor:
368                 case R_neg:
369                 case R_comp:
370                         reloc_stack_operate(ELF32_R_TYPE(rel[i].r_info), mod);
371                         break;
372                 default:
373                         printk(KERN_ERR "module %s: Unknown relocation: %u\n",
374                                mod->name, ELF32_R_TYPE(rel[i].r_info));
375                         return -ENOEXEC;
376                 }
377         }
378         return 0;
379 }
380
381 int
382 module_finalize(const Elf_Ehdr * hdr,
383                 const Elf_Shdr * sechdrs, struct module *mod)
384 {
385         unsigned int i, strindex = 0, symindex = 0;
386         char *secstrings;
387
388         secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
389
390         for (i = 1; i < hdr->e_shnum; i++) {
391                 /* Internal symbols and strings. */
392                 if (sechdrs[i].sh_type == SHT_SYMTAB) {
393                         symindex = i;
394                         strindex = sechdrs[i].sh_link;
395                 }
396         }
397
398         for (i = 1; i < hdr->e_shnum; i++) {
399                 const char *strtab = (char *)sechdrs[strindex].sh_addr;
400                 unsigned int info = sechdrs[i].sh_info;
401
402                 /* Not a valid relocation section? */
403                 if (info >= hdr->e_shnum)
404                         continue;
405
406                 if ((sechdrs[i].sh_type == SHT_RELA) &&
407                     ((strcmp(".rela.l1.text", secstrings + sechdrs[i].sh_name) == 0) ||
408                     ((strcmp(".rela.text", secstrings + sechdrs[i].sh_name) == 0) &&
409                          (hdr->e_flags & FLG_CODE_IN_L1)))) {
410                         apply_relocate_add((Elf_Shdr *) sechdrs, strtab,
411                                            symindex, i, mod);
412                 }
413         }
414         return 0;
415 }
416
417 void module_arch_cleanup(struct module *mod)
418 {
419         if ((mod->arch.text_l1) && (mod->arch.text_l1->sh_addr))
420                 l1_inst_sram_free((void *)mod->arch.text_l1->sh_addr);
421         if ((mod->arch.data_a_l1) && (mod->arch.data_a_l1->sh_addr))
422                 l1_data_sram_free((void *)mod->arch.data_a_l1->sh_addr);
423         if ((mod->arch.bss_a_l1) && (mod->arch.bss_a_l1->sh_addr))
424                 l1_data_sram_free((void *)mod->arch.bss_a_l1->sh_addr);
425         if ((mod->arch.data_b_l1) && (mod->arch.data_b_l1->sh_addr))
426                 l1_data_B_sram_free((void *)mod->arch.data_b_l1->sh_addr);
427         if ((mod->arch.bss_b_l1) && (mod->arch.bss_b_l1->sh_addr))
428                 l1_data_B_sram_free((void *)mod->arch.bss_b_l1->sh_addr);
429 }