2008-01-23 H.J. Lu <hongjiu.lu@intel.com>
[binutils.git] / bfd / elf32-m68hc12.c
blobba9293ba535c0b4e9b44c4cbd4a454f58630972b
1 /* Motorola 68HC12-specific support for 32-bit ELF
2 Copyright 1999, 2000, 2002, 2003, 2004, 2005, 2006, 2007
3 Free Software Foundation, Inc.
4 Contributed by Stephane Carrez (stcarrez@nerim.fr)
5 (Heavily copied from the D10V port by Martin Hunt (hunt@cygnus.com))
7 This file is part of BFD, the Binary File Descriptor library.
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 3 of the License, or
12 (at your option) any later version.
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with this program; if not, write to the Free Software
21 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
22 MA 02110-1301, USA. */
24 #include "sysdep.h"
25 #include "bfd.h"
26 #include "bfdlink.h"
27 #include "libbfd.h"
28 #include "elf-bfd.h"
29 #include "elf32-m68hc1x.h"
30 #include "elf/m68hc11.h"
31 #include "opcode/m68hc11.h"
33 /* Relocation functions. */
34 static reloc_howto_type *bfd_elf32_bfd_reloc_type_lookup
35 (bfd *, bfd_reloc_code_real_type);
36 static void m68hc11_info_to_howto_rel
37 (bfd *, arelent *, Elf_Internal_Rela *);
39 /* Trampoline generation. */
40 static bfd_boolean m68hc12_elf_size_one_stub
41 (struct bfd_hash_entry *gen_entry, void *in_arg);
42 static bfd_boolean m68hc12_elf_build_one_stub
43 (struct bfd_hash_entry *gen_entry, void *in_arg);
44 static struct bfd_link_hash_table* m68hc12_elf_bfd_link_hash_table_create
45 (bfd*);
47 static bfd_boolean m68hc12_elf_set_mach_from_flags PARAMS ((bfd *));
49 /* Use REL instead of RELA to save space */
50 #define USE_REL 1
52 /* The 68HC12 microcontroler has a memory bank switching system
53 with a 16Kb window in the 64Kb address space. The extended memory
54 is mapped in the 16Kb window (at 0x8000). The page register controls
55 which 16Kb bank is mapped. The call/rtc instructions take care of
56 bank switching in function calls/returns.
58 For GNU Binutils to work, we consider there is a physical memory
59 at 0..0x0ffff and a kind of virtual memory above that. Symbols
60 in virtual memory have their addresses treated in a special way
61 when disassembling and when linking.
63 For the linker to work properly, we must always relocate the virtual
64 memory as if it is mapped at 0x8000. When a 16-bit relocation is
65 made in the virtual memory, we check that it does not cross the
66 memory bank where it is used. This would involve a page change
67 which would be wrong. The 24-bit relocation is for that and it
68 treats the address as a physical address + page number.
71 Banked
72 Address Space
73 | | Page n
74 +---------------+ 0x1010000
75 | |
76 | jsr _foo |
77 | .. | Page 3
78 | _foo: |
79 +---------------+ 0x100C000
80 | |
81 | call _bar |
82 | .. | Page 2
83 | _bar: |
84 +---------------+ 0x1008000
85 /------>| |
86 | | call _foo | Page 1
87 | | |
88 | +---------------+ 0x1004000
89 Physical | | |
90 Address Space | | | Page 0
91 | | |
92 +-----------+ 0x00FFFF | +---------------+ 0x1000000
93 | | |
94 | call _foo | |
95 | | |
96 +-----------+ 0x00BFFF -+---/
97 | | |
98 | | |
99 | | 16K |
100 | | |
101 +-----------+ 0x008000 -+
107 +-----------+ 0000
110 The 'call _foo' must be relocated with page 3 and 16-bit address
111 mapped at 0x8000.
113 The 3-bit and 16-bit PC rel relocation is only used by 68HC12. */
114 static reloc_howto_type elf_m68hc11_howto_table[] = {
115 /* This reloc does nothing. */
116 HOWTO (R_M68HC11_NONE, /* type */
117 0, /* rightshift */
118 2, /* size (0 = byte, 1 = short, 2 = long) */
119 32, /* bitsize */
120 FALSE, /* pc_relative */
121 0, /* bitpos */
122 complain_overflow_dont,/* complain_on_overflow */
123 bfd_elf_generic_reloc, /* special_function */
124 "R_M68HC12_NONE", /* name */
125 FALSE, /* partial_inplace */
126 0, /* src_mask */
127 0, /* dst_mask */
128 FALSE), /* pcrel_offset */
130 /* A 8 bit absolute relocation */
131 HOWTO (R_M68HC11_8, /* type */
132 0, /* rightshift */
133 0, /* size (0 = byte, 1 = short, 2 = long) */
134 8, /* bitsize */
135 FALSE, /* pc_relative */
136 0, /* bitpos */
137 complain_overflow_bitfield, /* complain_on_overflow */
138 bfd_elf_generic_reloc, /* special_function */
139 "R_M68HC12_8", /* name */
140 FALSE, /* partial_inplace */
141 0x00ff, /* src_mask */
142 0x00ff, /* dst_mask */
143 FALSE), /* pcrel_offset */
145 /* A 8 bit absolute relocation (upper address) */
146 HOWTO (R_M68HC11_HI8, /* type */
147 8, /* rightshift */
148 0, /* size (0 = byte, 1 = short, 2 = long) */
149 8, /* bitsize */
150 FALSE, /* pc_relative */
151 0, /* bitpos */
152 complain_overflow_bitfield, /* complain_on_overflow */
153 bfd_elf_generic_reloc, /* special_function */
154 "R_M68HC12_HI8", /* name */
155 FALSE, /* partial_inplace */
156 0x00ff, /* src_mask */
157 0x00ff, /* dst_mask */
158 FALSE), /* pcrel_offset */
160 /* A 8 bit absolute relocation (upper address) */
161 HOWTO (R_M68HC11_LO8, /* type */
162 0, /* rightshift */
163 0, /* size (0 = byte, 1 = short, 2 = long) */
164 8, /* bitsize */
165 FALSE, /* pc_relative */
166 0, /* bitpos */
167 complain_overflow_dont, /* complain_on_overflow */
168 bfd_elf_generic_reloc, /* special_function */
169 "R_M68HC12_LO8", /* name */
170 FALSE, /* partial_inplace */
171 0x00ff, /* src_mask */
172 0x00ff, /* dst_mask */
173 FALSE), /* pcrel_offset */
175 /* A 8 bit PC-rel relocation */
176 HOWTO (R_M68HC11_PCREL_8, /* type */
177 0, /* rightshift */
178 0, /* size (0 = byte, 1 = short, 2 = long) */
179 8, /* bitsize */
180 TRUE, /* pc_relative */
181 0, /* bitpos */
182 complain_overflow_bitfield, /* complain_on_overflow */
183 bfd_elf_generic_reloc, /* special_function */
184 "R_M68HC12_PCREL_8", /* name */
185 FALSE, /* partial_inplace */
186 0x00ff, /* src_mask */
187 0x00ff, /* dst_mask */
188 TRUE), /* pcrel_offset */
190 /* A 16 bit absolute relocation */
191 HOWTO (R_M68HC11_16, /* type */
192 0, /* rightshift */
193 1, /* size (0 = byte, 1 = short, 2 = long) */
194 16, /* bitsize */
195 FALSE, /* pc_relative */
196 0, /* bitpos */
197 complain_overflow_dont /*bitfield */ , /* complain_on_overflow */
198 bfd_elf_generic_reloc, /* special_function */
199 "R_M68HC12_16", /* name */
200 FALSE, /* partial_inplace */
201 0xffff, /* src_mask */
202 0xffff, /* dst_mask */
203 FALSE), /* pcrel_offset */
205 /* A 32 bit absolute relocation. This one is never used for the
206 code relocation. It's used by gas for -gstabs generation. */
207 HOWTO (R_M68HC11_32, /* type */
208 0, /* rightshift */
209 2, /* size (0 = byte, 1 = short, 2 = long) */
210 32, /* bitsize */
211 FALSE, /* pc_relative */
212 0, /* bitpos */
213 complain_overflow_bitfield, /* complain_on_overflow */
214 bfd_elf_generic_reloc, /* special_function */
215 "R_M68HC12_32", /* name */
216 FALSE, /* partial_inplace */
217 0xffffffff, /* src_mask */
218 0xffffffff, /* dst_mask */
219 FALSE), /* pcrel_offset */
221 /* A 3 bit absolute relocation */
222 HOWTO (R_M68HC11_3B, /* type */
223 0, /* rightshift */
224 0, /* size (0 = byte, 1 = short, 2 = long) */
225 3, /* bitsize */
226 FALSE, /* pc_relative */
227 0, /* bitpos */
228 complain_overflow_bitfield, /* complain_on_overflow */
229 bfd_elf_generic_reloc, /* special_function */
230 "R_M68HC12_4B", /* name */
231 FALSE, /* partial_inplace */
232 0x003, /* src_mask */
233 0x003, /* dst_mask */
234 FALSE), /* pcrel_offset */
236 /* A 16 bit PC-rel relocation */
237 HOWTO (R_M68HC11_PCREL_16, /* type */
238 0, /* rightshift */
239 1, /* size (0 = byte, 1 = short, 2 = long) */
240 16, /* bitsize */
241 TRUE, /* pc_relative */
242 0, /* bitpos */
243 complain_overflow_dont, /* complain_on_overflow */
244 bfd_elf_generic_reloc, /* special_function */
245 "R_M68HC12_PCREL_16", /* name */
246 FALSE, /* partial_inplace */
247 0xffff, /* src_mask */
248 0xffff, /* dst_mask */
249 TRUE), /* pcrel_offset */
251 /* GNU extension to record C++ vtable hierarchy */
252 HOWTO (R_M68HC11_GNU_VTINHERIT, /* type */
253 0, /* rightshift */
254 1, /* size (0 = byte, 1 = short, 2 = long) */
255 0, /* bitsize */
256 FALSE, /* pc_relative */
257 0, /* bitpos */
258 complain_overflow_dont, /* complain_on_overflow */
259 NULL, /* special_function */
260 "R_M68HC11_GNU_VTINHERIT", /* name */
261 FALSE, /* partial_inplace */
262 0, /* src_mask */
263 0, /* dst_mask */
264 FALSE), /* pcrel_offset */
266 /* GNU extension to record C++ vtable member usage */
267 HOWTO (R_M68HC11_GNU_VTENTRY, /* type */
268 0, /* rightshift */
269 1, /* size (0 = byte, 1 = short, 2 = long) */
270 0, /* bitsize */
271 FALSE, /* pc_relative */
272 0, /* bitpos */
273 complain_overflow_dont, /* complain_on_overflow */
274 _bfd_elf_rel_vtable_reloc_fn, /* special_function */
275 "R_M68HC11_GNU_VTENTRY", /* name */
276 FALSE, /* partial_inplace */
277 0, /* src_mask */
278 0, /* dst_mask */
279 FALSE), /* pcrel_offset */
281 /* A 24 bit relocation */
282 HOWTO (R_M68HC11_24, /* type */
283 0, /* rightshift */
284 2, /* size (0 = byte, 1 = short, 2 = long) */
285 24, /* bitsize */
286 FALSE, /* pc_relative */
287 0, /* bitpos */
288 complain_overflow_dont, /* complain_on_overflow */
289 m68hc11_elf_special_reloc, /* special_function */
290 "R_M68HC12_24", /* name */
291 FALSE, /* partial_inplace */
292 0xffffff, /* src_mask */
293 0xffffff, /* dst_mask */
294 FALSE), /* pcrel_offset */
296 /* A 16-bit low relocation */
297 HOWTO (R_M68HC11_LO16, /* type */
298 0, /* rightshift */
299 1, /* size (0 = byte, 1 = short, 2 = long) */
300 16, /* bitsize */
301 FALSE, /* pc_relative */
302 0, /* bitpos */
303 complain_overflow_dont, /* complain_on_overflow */
304 m68hc11_elf_special_reloc,/* special_function */
305 "R_M68HC12_LO16", /* name */
306 FALSE, /* partial_inplace */
307 0xffff, /* src_mask */
308 0xffff, /* dst_mask */
309 FALSE), /* pcrel_offset */
311 /* A page relocation */
312 HOWTO (R_M68HC11_PAGE, /* type */
313 0, /* rightshift */
314 0, /* size (0 = byte, 1 = short, 2 = long) */
315 8, /* bitsize */
316 FALSE, /* pc_relative */
317 0, /* bitpos */
318 complain_overflow_dont, /* complain_on_overflow */
319 m68hc11_elf_special_reloc,/* special_function */
320 "R_M68HC12_PAGE", /* name */
321 FALSE, /* partial_inplace */
322 0x00ff, /* src_mask */
323 0x00ff, /* dst_mask */
324 FALSE), /* pcrel_offset */
326 EMPTY_HOWTO (14),
327 EMPTY_HOWTO (15),
328 EMPTY_HOWTO (16),
329 EMPTY_HOWTO (17),
330 EMPTY_HOWTO (18),
331 EMPTY_HOWTO (19),
333 /* Mark beginning of a jump instruction (any form). */
334 HOWTO (R_M68HC11_RL_JUMP, /* type */
335 0, /* rightshift */
336 1, /* size (0 = byte, 1 = short, 2 = long) */
337 0, /* bitsize */
338 FALSE, /* pc_relative */
339 0, /* bitpos */
340 complain_overflow_dont, /* complain_on_overflow */
341 m68hc11_elf_ignore_reloc, /* special_function */
342 "R_M68HC12_RL_JUMP", /* name */
343 TRUE, /* partial_inplace */
344 0, /* src_mask */
345 0, /* dst_mask */
346 TRUE), /* pcrel_offset */
348 /* Mark beginning of Gcc relaxation group instruction. */
349 HOWTO (R_M68HC11_RL_GROUP, /* type */
350 0, /* rightshift */
351 1, /* size (0 = byte, 1 = short, 2 = long) */
352 0, /* bitsize */
353 FALSE, /* pc_relative */
354 0, /* bitpos */
355 complain_overflow_dont, /* complain_on_overflow */
356 m68hc11_elf_ignore_reloc, /* special_function */
357 "R_M68HC12_RL_GROUP", /* name */
358 TRUE, /* partial_inplace */
359 0, /* src_mask */
360 0, /* dst_mask */
361 TRUE), /* pcrel_offset */
364 /* Map BFD reloc types to M68HC11 ELF reloc types. */
366 struct m68hc11_reloc_map
368 bfd_reloc_code_real_type bfd_reloc_val;
369 unsigned char elf_reloc_val;
372 static const struct m68hc11_reloc_map m68hc11_reloc_map[] = {
373 {BFD_RELOC_NONE, R_M68HC11_NONE,},
374 {BFD_RELOC_8, R_M68HC11_8},
375 {BFD_RELOC_M68HC11_HI8, R_M68HC11_HI8},
376 {BFD_RELOC_M68HC11_LO8, R_M68HC11_LO8},
377 {BFD_RELOC_8_PCREL, R_M68HC11_PCREL_8},
378 {BFD_RELOC_16_PCREL, R_M68HC11_PCREL_16},
379 {BFD_RELOC_16, R_M68HC11_16},
380 {BFD_RELOC_32, R_M68HC11_32},
381 {BFD_RELOC_M68HC11_3B, R_M68HC11_3B},
383 {BFD_RELOC_VTABLE_INHERIT, R_M68HC11_GNU_VTINHERIT},
384 {BFD_RELOC_VTABLE_ENTRY, R_M68HC11_GNU_VTENTRY},
386 {BFD_RELOC_M68HC11_LO16, R_M68HC11_LO16},
387 {BFD_RELOC_M68HC11_PAGE, R_M68HC11_PAGE},
388 {BFD_RELOC_M68HC11_24, R_M68HC11_24},
390 {BFD_RELOC_M68HC11_RL_JUMP, R_M68HC11_RL_JUMP},
391 {BFD_RELOC_M68HC11_RL_GROUP, R_M68HC11_RL_GROUP},
394 static reloc_howto_type *
395 bfd_elf32_bfd_reloc_type_lookup (bfd *abfd ATTRIBUTE_UNUSED,
396 bfd_reloc_code_real_type code)
398 unsigned int i;
400 for (i = 0;
401 i < sizeof (m68hc11_reloc_map) / sizeof (struct m68hc11_reloc_map);
402 i++)
404 if (m68hc11_reloc_map[i].bfd_reloc_val == code)
405 return &elf_m68hc11_howto_table[m68hc11_reloc_map[i].elf_reloc_val];
408 return NULL;
411 static reloc_howto_type *
412 bfd_elf32_bfd_reloc_name_lookup (bfd *abfd ATTRIBUTE_UNUSED,
413 const char *r_name)
415 unsigned int i;
417 for (i = 0;
418 i < (sizeof (elf_m68hc11_howto_table)
419 / sizeof (elf_m68hc11_howto_table[0]));
420 i++)
421 if (elf_m68hc11_howto_table[i].name != NULL
422 && strcasecmp (elf_m68hc11_howto_table[i].name, r_name) == 0)
423 return &elf_m68hc11_howto_table[i];
425 return NULL;
428 /* Set the howto pointer for an M68HC11 ELF reloc. */
430 static void
431 m68hc11_info_to_howto_rel (bfd *abfd ATTRIBUTE_UNUSED,
432 arelent *cache_ptr, Elf_Internal_Rela *dst)
434 unsigned int r_type;
436 r_type = ELF32_R_TYPE (dst->r_info);
437 BFD_ASSERT (r_type < (unsigned int) R_M68HC11_max);
438 cache_ptr->howto = &elf_m68hc11_howto_table[r_type];
442 /* Far trampoline generation. */
444 /* Build a 68HC12 trampoline stub. */
445 static bfd_boolean
446 m68hc12_elf_build_one_stub (struct bfd_hash_entry *gen_entry, void *in_arg)
448 struct elf32_m68hc11_stub_hash_entry *stub_entry;
449 struct bfd_link_info *info;
450 struct m68hc11_elf_link_hash_table *htab;
451 asection *stub_sec;
452 bfd *stub_bfd;
453 bfd_byte *loc;
454 bfd_vma sym_value, phys_page, phys_addr;
456 /* Massage our args to the form they really have. */
457 stub_entry = (struct elf32_m68hc11_stub_hash_entry *) gen_entry;
458 info = (struct bfd_link_info *) in_arg;
460 htab = m68hc11_elf_hash_table (info);
462 stub_sec = stub_entry->stub_sec;
464 /* Make a note of the offset within the stubs for this entry. */
465 stub_entry->stub_offset = stub_sec->size;
466 stub_sec->size += 7;
467 loc = stub_sec->contents + stub_entry->stub_offset;
469 stub_bfd = stub_sec->owner;
471 /* Create the trampoline call stub:
473 ldy #%addr(symbol)
474 call %page(symbol), __trampoline
477 sym_value = (stub_entry->target_value
478 + stub_entry->target_section->output_offset
479 + stub_entry->target_section->output_section->vma);
480 phys_addr = m68hc11_phys_addr (&htab->pinfo, sym_value);
481 phys_page = m68hc11_phys_page (&htab->pinfo, sym_value);
483 /* ldy #%page(sym) */
484 bfd_put_8 (stub_bfd, 0xCD, loc);
485 bfd_put_16 (stub_bfd, phys_addr, loc + 1);
486 loc += 3;
488 /* call %page(sym), __trampoline */
489 bfd_put_8 (stub_bfd, 0x4a, loc);
490 bfd_put_16 (stub_bfd, htab->pinfo.trampoline_addr, loc + 1);
491 bfd_put_8 (stub_bfd, phys_page, loc + 3);
493 return TRUE;
496 /* As above, but don't actually build the stub. Just bump offset so
497 we know stub section sizes. */
499 static bfd_boolean
500 m68hc12_elf_size_one_stub (struct bfd_hash_entry *gen_entry,
501 void *in_arg ATTRIBUTE_UNUSED)
503 struct elf32_m68hc11_stub_hash_entry *stub_entry;
505 /* Massage our args to the form they really have. */
506 stub_entry = (struct elf32_m68hc11_stub_hash_entry *) gen_entry;
508 stub_entry->stub_sec->size += 7;
509 return TRUE;
512 /* Create a 68HC12 ELF linker hash table. */
514 static struct bfd_link_hash_table *
515 m68hc12_elf_bfd_link_hash_table_create (bfd *abfd)
517 struct m68hc11_elf_link_hash_table *ret;
519 ret = m68hc11_elf_hash_table_create (abfd);
520 if (ret == (struct m68hc11_elf_link_hash_table *) NULL)
521 return NULL;
523 ret->size_one_stub = m68hc12_elf_size_one_stub;
524 ret->build_one_stub = m68hc12_elf_build_one_stub;
526 return &ret->root.root;
529 static bfd_boolean
530 m68hc12_elf_set_mach_from_flags (bfd *abfd)
532 flagword flags = elf_elfheader (abfd)->e_flags;
534 switch (flags & EF_M68HC11_MACH_MASK)
536 case EF_M68HC12_MACH:
537 bfd_default_set_arch_mach (abfd, bfd_arch_m68hc12, bfd_mach_m6812);
538 break;
539 case EF_M68HCS12_MACH:
540 bfd_default_set_arch_mach (abfd, bfd_arch_m68hc12, bfd_mach_m6812s);
541 break;
542 case EF_M68HC11_GENERIC:
543 bfd_default_set_arch_mach (abfd, bfd_arch_m68hc12,
544 bfd_mach_m6812_default);
545 break;
546 default:
547 return FALSE;
549 return TRUE;
552 /* Specific sections:
553 - The .page0 is a data section that is mapped in [0x0000..0x00FF].
554 Page0 accesses are faster on the M68HC12.
555 - The .vectors is the section that represents the interrupt
556 vectors. */
557 static const struct bfd_elf_special_section elf32_m68hc12_special_sections[] =
559 { STRING_COMMA_LEN (".eeprom"), 0, SHT_PROGBITS, SHF_ALLOC + SHF_WRITE },
560 { STRING_COMMA_LEN (".page0"), 0, SHT_PROGBITS, SHF_ALLOC + SHF_WRITE },
561 { STRING_COMMA_LEN (".softregs"), 0, SHT_NOBITS, SHF_ALLOC + SHF_WRITE },
562 { STRING_COMMA_LEN (".vectors"), 0, SHT_PROGBITS, SHF_ALLOC },
563 { NULL, 0, 0, 0, 0 }
566 #define ELF_ARCH bfd_arch_m68hc12
567 #define ELF_MACHINE_CODE EM_68HC12
568 #define ELF_MAXPAGESIZE 0x1000
570 #define TARGET_BIG_SYM bfd_elf32_m68hc12_vec
571 #define TARGET_BIG_NAME "elf32-m68hc12"
573 #define elf_info_to_howto 0
574 #define elf_info_to_howto_rel m68hc11_info_to_howto_rel
575 #define elf_backend_check_relocs elf32_m68hc11_check_relocs
576 #define elf_backend_relocate_section elf32_m68hc11_relocate_section
577 #define elf_backend_object_p m68hc12_elf_set_mach_from_flags
578 #define elf_backend_final_write_processing 0
579 #define elf_backend_can_gc_sections 1
580 #define elf_backend_special_sections elf32_m68hc12_special_sections
581 #define elf_backend_post_process_headers elf32_m68hc11_post_process_headers
582 #define elf_backend_add_symbol_hook elf32_m68hc11_add_symbol_hook
584 #define bfd_elf32_bfd_link_hash_table_create \
585 m68hc12_elf_bfd_link_hash_table_create
586 #define bfd_elf32_bfd_link_hash_table_free \
587 m68hc11_elf_bfd_link_hash_table_free
588 #define bfd_elf32_bfd_merge_private_bfd_data \
589 _bfd_m68hc11_elf_merge_private_bfd_data
590 #define bfd_elf32_bfd_set_private_flags _bfd_m68hc11_elf_set_private_flags
591 #define bfd_elf32_bfd_print_private_bfd_data \
592 _bfd_m68hc11_elf_print_private_bfd_data
594 #include "elf32-target.h"