bfd/
[binutils.git] / bfd / elf32-m68hc12.c
blobb52f3fff853fa42a6fdf95041405c77968e20778
1 /* Motorola 68HC12-specific support for 32-bit ELF
2 Copyright 1999, 2000, 2002, 2003, 2004 Free Software Foundation, Inc.
3 Contributed by Stephane Carrez (stcarrez@nerim.fr)
4 (Heavily copied from the D10V port by Martin Hunt (hunt@cygnus.com))
6 This file is part of BFD, the Binary File Descriptor library.
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 2 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program; if not, write to the Free Software
20 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA. */
22 #include "bfd.h"
23 #include "sysdep.h"
24 #include "bfdlink.h"
25 #include "libbfd.h"
26 #include "elf-bfd.h"
27 #include "elf32-m68hc1x.h"
28 #include "elf/m68hc11.h"
29 #include "opcode/m68hc11.h"
31 /* Relocation functions. */
32 static reloc_howto_type *bfd_elf32_bfd_reloc_type_lookup
33 (bfd *, bfd_reloc_code_real_type);
34 static void m68hc11_info_to_howto_rel
35 (bfd *, arelent *, Elf_Internal_Rela *);
37 /* Trampoline generation. */
38 static bfd_boolean m68hc12_elf_size_one_stub
39 (struct bfd_hash_entry *gen_entry, void *in_arg);
40 static bfd_boolean m68hc12_elf_build_one_stub
41 (struct bfd_hash_entry *gen_entry, void *in_arg);
42 static struct bfd_link_hash_table* m68hc12_elf_bfd_link_hash_table_create
43 (bfd*);
45 static bfd_boolean m68hc12_elf_set_mach_from_flags PARAMS ((bfd *));
47 /* Use REL instead of RELA to save space */
48 #define USE_REL 1
50 /* The 68HC12 microcontroler has a memory bank switching system
51 with a 16Kb window in the 64Kb address space. The extended memory
52 is mapped in the 16Kb window (at 0x8000). The page register controls
53 which 16Kb bank is mapped. The call/rtc instructions take care of
54 bank switching in function calls/returns.
56 For GNU Binutils to work, we consider there is a physical memory
57 at 0..0x0ffff and a kind of virtual memory above that. Symbols
58 in virtual memory have their addresses treated in a special way
59 when disassembling and when linking.
61 For the linker to work properly, we must always relocate the virtual
62 memory as if it is mapped at 0x8000. When a 16-bit relocation is
63 made in the virtual memory, we check that it does not cross the
64 memory bank where it is used. This would involve a page change
65 which would be wrong. The 24-bit relocation is for that and it
66 treats the address as a physical address + page number.
69 Banked
70 Address Space
71 | | Page n
72 +---------------+ 0x1010000
73 | |
74 | jsr _foo |
75 | .. | Page 3
76 | _foo: |
77 +---------------+ 0x100C000
78 | |
79 | call _bar |
80 | .. | Page 2
81 | _bar: |
82 +---------------+ 0x1008000
83 /------>| |
84 | | call _foo | Page 1
85 | | |
86 | +---------------+ 0x1004000
87 Physical | | |
88 Address Space | | | Page 0
89 | | |
90 +-----------+ 0x00FFFF | +---------------+ 0x1000000
91 | | |
92 | call _foo | |
93 | | |
94 +-----------+ 0x00BFFF -+---/
95 | | |
96 | | |
97 | | 16K |
98 | | |
99 +-----------+ 0x008000 -+
105 +-----------+ 0000
108 The 'call _foo' must be relocated with page 3 and 16-bit address
109 mapped at 0x8000.
111 The 3-bit and 16-bit PC rel relocation is only used by 68HC12. */
112 static reloc_howto_type elf_m68hc11_howto_table[] = {
113 /* This reloc does nothing. */
114 HOWTO (R_M68HC11_NONE, /* type */
115 0, /* rightshift */
116 2, /* size (0 = byte, 1 = short, 2 = long) */
117 32, /* bitsize */
118 FALSE, /* pc_relative */
119 0, /* bitpos */
120 complain_overflow_dont,/* complain_on_overflow */
121 bfd_elf_generic_reloc, /* special_function */
122 "R_M68HC12_NONE", /* name */
123 FALSE, /* partial_inplace */
124 0, /* src_mask */
125 0, /* dst_mask */
126 FALSE), /* pcrel_offset */
128 /* A 8 bit absolute relocation */
129 HOWTO (R_M68HC11_8, /* type */
130 0, /* rightshift */
131 0, /* size (0 = byte, 1 = short, 2 = long) */
132 8, /* bitsize */
133 FALSE, /* pc_relative */
134 0, /* bitpos */
135 complain_overflow_bitfield, /* complain_on_overflow */
136 bfd_elf_generic_reloc, /* special_function */
137 "R_M68HC12_8", /* name */
138 FALSE, /* partial_inplace */
139 0x00ff, /* src_mask */
140 0x00ff, /* dst_mask */
141 FALSE), /* pcrel_offset */
143 /* A 8 bit absolute relocation (upper address) */
144 HOWTO (R_M68HC11_HI8, /* type */
145 8, /* rightshift */
146 0, /* size (0 = byte, 1 = short, 2 = long) */
147 8, /* bitsize */
148 FALSE, /* pc_relative */
149 0, /* bitpos */
150 complain_overflow_bitfield, /* complain_on_overflow */
151 bfd_elf_generic_reloc, /* special_function */
152 "R_M68HC12_HI8", /* name */
153 FALSE, /* partial_inplace */
154 0x00ff, /* src_mask */
155 0x00ff, /* dst_mask */
156 FALSE), /* pcrel_offset */
158 /* A 8 bit absolute relocation (upper address) */
159 HOWTO (R_M68HC11_LO8, /* type */
160 0, /* rightshift */
161 0, /* size (0 = byte, 1 = short, 2 = long) */
162 8, /* bitsize */
163 FALSE, /* pc_relative */
164 0, /* bitpos */
165 complain_overflow_dont, /* complain_on_overflow */
166 bfd_elf_generic_reloc, /* special_function */
167 "R_M68HC12_LO8", /* name */
168 FALSE, /* partial_inplace */
169 0x00ff, /* src_mask */
170 0x00ff, /* dst_mask */
171 FALSE), /* pcrel_offset */
173 /* A 8 bit PC-rel relocation */
174 HOWTO (R_M68HC11_PCREL_8, /* type */
175 0, /* rightshift */
176 0, /* size (0 = byte, 1 = short, 2 = long) */
177 8, /* bitsize */
178 TRUE, /* pc_relative */
179 0, /* bitpos */
180 complain_overflow_bitfield, /* complain_on_overflow */
181 bfd_elf_generic_reloc, /* special_function */
182 "R_M68HC12_PCREL_8", /* name */
183 FALSE, /* partial_inplace */
184 0x00ff, /* src_mask */
185 0x00ff, /* dst_mask */
186 TRUE), /* pcrel_offset */
188 /* A 16 bit absolute relocation */
189 HOWTO (R_M68HC11_16, /* type */
190 0, /* rightshift */
191 1, /* size (0 = byte, 1 = short, 2 = long) */
192 16, /* bitsize */
193 FALSE, /* pc_relative */
194 0, /* bitpos */
195 complain_overflow_dont /*bitfield */ , /* complain_on_overflow */
196 bfd_elf_generic_reloc, /* special_function */
197 "R_M68HC12_16", /* name */
198 FALSE, /* partial_inplace */
199 0xffff, /* src_mask */
200 0xffff, /* dst_mask */
201 FALSE), /* pcrel_offset */
203 /* A 32 bit absolute relocation. This one is never used for the
204 code relocation. It's used by gas for -gstabs generation. */
205 HOWTO (R_M68HC11_32, /* type */
206 0, /* rightshift */
207 2, /* size (0 = byte, 1 = short, 2 = long) */
208 32, /* bitsize */
209 FALSE, /* pc_relative */
210 0, /* bitpos */
211 complain_overflow_bitfield, /* complain_on_overflow */
212 bfd_elf_generic_reloc, /* special_function */
213 "R_M68HC12_32", /* name */
214 FALSE, /* partial_inplace */
215 0xffffffff, /* src_mask */
216 0xffffffff, /* dst_mask */
217 FALSE), /* pcrel_offset */
219 /* A 3 bit absolute relocation */
220 HOWTO (R_M68HC11_3B, /* type */
221 0, /* rightshift */
222 0, /* size (0 = byte, 1 = short, 2 = long) */
223 3, /* bitsize */
224 FALSE, /* pc_relative */
225 0, /* bitpos */
226 complain_overflow_bitfield, /* complain_on_overflow */
227 bfd_elf_generic_reloc, /* special_function */
228 "R_M68HC12_4B", /* name */
229 FALSE, /* partial_inplace */
230 0x003, /* src_mask */
231 0x003, /* dst_mask */
232 FALSE), /* pcrel_offset */
234 /* A 16 bit PC-rel relocation */
235 HOWTO (R_M68HC11_PCREL_16, /* type */
236 0, /* rightshift */
237 1, /* size (0 = byte, 1 = short, 2 = long) */
238 16, /* bitsize */
239 TRUE, /* pc_relative */
240 0, /* bitpos */
241 complain_overflow_dont, /* complain_on_overflow */
242 bfd_elf_generic_reloc, /* special_function */
243 "R_M68HC12_PCREL_16", /* name */
244 FALSE, /* partial_inplace */
245 0xffff, /* src_mask */
246 0xffff, /* dst_mask */
247 TRUE), /* pcrel_offset */
249 /* GNU extension to record C++ vtable hierarchy */
250 HOWTO (R_M68HC11_GNU_VTINHERIT, /* type */
251 0, /* rightshift */
252 1, /* size (0 = byte, 1 = short, 2 = long) */
253 0, /* bitsize */
254 FALSE, /* pc_relative */
255 0, /* bitpos */
256 complain_overflow_dont, /* complain_on_overflow */
257 NULL, /* special_function */
258 "R_M68HC11_GNU_VTINHERIT", /* name */
259 FALSE, /* partial_inplace */
260 0, /* src_mask */
261 0, /* dst_mask */
262 FALSE), /* pcrel_offset */
264 /* GNU extension to record C++ vtable member usage */
265 HOWTO (R_M68HC11_GNU_VTENTRY, /* type */
266 0, /* rightshift */
267 1, /* size (0 = byte, 1 = short, 2 = long) */
268 0, /* bitsize */
269 FALSE, /* pc_relative */
270 0, /* bitpos */
271 complain_overflow_dont, /* complain_on_overflow */
272 _bfd_elf_rel_vtable_reloc_fn, /* special_function */
273 "R_M68HC11_GNU_VTENTRY", /* name */
274 FALSE, /* partial_inplace */
275 0, /* src_mask */
276 0, /* dst_mask */
277 FALSE), /* pcrel_offset */
279 /* A 24 bit relocation */
280 HOWTO (R_M68HC11_24, /* type */
281 0, /* rightshift */
282 2, /* size (0 = byte, 1 = short, 2 = long) */
283 24, /* bitsize */
284 FALSE, /* pc_relative */
285 0, /* bitpos */
286 complain_overflow_dont, /* complain_on_overflow */
287 m68hc11_elf_special_reloc, /* special_function */
288 "R_M68HC12_24", /* name */
289 FALSE, /* partial_inplace */
290 0xffffff, /* src_mask */
291 0xffffff, /* dst_mask */
292 FALSE), /* pcrel_offset */
294 /* A 16-bit low relocation */
295 HOWTO (R_M68HC11_LO16, /* type */
296 0, /* rightshift */
297 1, /* size (0 = byte, 1 = short, 2 = long) */
298 16, /* bitsize */
299 FALSE, /* pc_relative */
300 0, /* bitpos */
301 complain_overflow_dont, /* complain_on_overflow */
302 m68hc11_elf_special_reloc,/* special_function */
303 "R_M68HC12_LO16", /* name */
304 FALSE, /* partial_inplace */
305 0xffff, /* src_mask */
306 0xffff, /* dst_mask */
307 FALSE), /* pcrel_offset */
309 /* A page relocation */
310 HOWTO (R_M68HC11_PAGE, /* type */
311 0, /* rightshift */
312 0, /* size (0 = byte, 1 = short, 2 = long) */
313 8, /* bitsize */
314 FALSE, /* pc_relative */
315 0, /* bitpos */
316 complain_overflow_dont, /* complain_on_overflow */
317 m68hc11_elf_special_reloc,/* special_function */
318 "R_M68HC12_PAGE", /* name */
319 FALSE, /* partial_inplace */
320 0x00ff, /* src_mask */
321 0x00ff, /* dst_mask */
322 FALSE), /* pcrel_offset */
324 EMPTY_HOWTO (14),
325 EMPTY_HOWTO (15),
326 EMPTY_HOWTO (16),
327 EMPTY_HOWTO (17),
328 EMPTY_HOWTO (18),
329 EMPTY_HOWTO (19),
331 /* Mark beginning of a jump instruction (any form). */
332 HOWTO (R_M68HC11_RL_JUMP, /* type */
333 0, /* rightshift */
334 1, /* size (0 = byte, 1 = short, 2 = long) */
335 0, /* bitsize */
336 FALSE, /* pc_relative */
337 0, /* bitpos */
338 complain_overflow_dont, /* complain_on_overflow */
339 m68hc11_elf_ignore_reloc, /* special_function */
340 "R_M68HC12_RL_JUMP", /* name */
341 TRUE, /* partial_inplace */
342 0, /* src_mask */
343 0, /* dst_mask */
344 TRUE), /* pcrel_offset */
346 /* Mark beginning of Gcc relaxation group instruction. */
347 HOWTO (R_M68HC11_RL_GROUP, /* type */
348 0, /* rightshift */
349 1, /* size (0 = byte, 1 = short, 2 = long) */
350 0, /* bitsize */
351 FALSE, /* pc_relative */
352 0, /* bitpos */
353 complain_overflow_dont, /* complain_on_overflow */
354 m68hc11_elf_ignore_reloc, /* special_function */
355 "R_M68HC12_RL_GROUP", /* name */
356 TRUE, /* partial_inplace */
357 0, /* src_mask */
358 0, /* dst_mask */
359 TRUE), /* pcrel_offset */
362 /* Map BFD reloc types to M68HC11 ELF reloc types. */
364 struct m68hc11_reloc_map
366 bfd_reloc_code_real_type bfd_reloc_val;
367 unsigned char elf_reloc_val;
370 static const struct m68hc11_reloc_map m68hc11_reloc_map[] = {
371 {BFD_RELOC_NONE, R_M68HC11_NONE,},
372 {BFD_RELOC_8, R_M68HC11_8},
373 {BFD_RELOC_M68HC11_HI8, R_M68HC11_HI8},
374 {BFD_RELOC_M68HC11_LO8, R_M68HC11_LO8},
375 {BFD_RELOC_8_PCREL, R_M68HC11_PCREL_8},
376 {BFD_RELOC_16_PCREL, R_M68HC11_PCREL_16},
377 {BFD_RELOC_16, R_M68HC11_16},
378 {BFD_RELOC_32, R_M68HC11_32},
379 {BFD_RELOC_M68HC11_3B, R_M68HC11_3B},
381 {BFD_RELOC_VTABLE_INHERIT, R_M68HC11_GNU_VTINHERIT},
382 {BFD_RELOC_VTABLE_ENTRY, R_M68HC11_GNU_VTENTRY},
384 {BFD_RELOC_M68HC11_LO16, R_M68HC11_LO16},
385 {BFD_RELOC_M68HC11_PAGE, R_M68HC11_PAGE},
386 {BFD_RELOC_M68HC11_24, R_M68HC11_24},
388 {BFD_RELOC_M68HC11_RL_JUMP, R_M68HC11_RL_JUMP},
389 {BFD_RELOC_M68HC11_RL_GROUP, R_M68HC11_RL_GROUP},
392 static reloc_howto_type *
393 bfd_elf32_bfd_reloc_type_lookup (bfd *abfd ATTRIBUTE_UNUSED,
394 bfd_reloc_code_real_type code)
396 unsigned int i;
398 for (i = 0;
399 i < sizeof (m68hc11_reloc_map) / sizeof (struct m68hc11_reloc_map);
400 i++)
402 if (m68hc11_reloc_map[i].bfd_reloc_val == code)
403 return &elf_m68hc11_howto_table[m68hc11_reloc_map[i].elf_reloc_val];
406 return NULL;
409 /* Set the howto pointer for an M68HC11 ELF reloc. */
411 static void
412 m68hc11_info_to_howto_rel (bfd *abfd ATTRIBUTE_UNUSED,
413 arelent *cache_ptr, Elf_Internal_Rela *dst)
415 unsigned int r_type;
417 r_type = ELF32_R_TYPE (dst->r_info);
418 BFD_ASSERT (r_type < (unsigned int) R_M68HC11_max);
419 cache_ptr->howto = &elf_m68hc11_howto_table[r_type];
423 /* Far trampoline generation. */
425 /* Build a 68HC12 trampoline stub. */
426 static bfd_boolean
427 m68hc12_elf_build_one_stub (struct bfd_hash_entry *gen_entry, void *in_arg)
429 struct elf32_m68hc11_stub_hash_entry *stub_entry;
430 struct bfd_link_info *info;
431 struct m68hc11_elf_link_hash_table *htab;
432 asection *stub_sec;
433 bfd *stub_bfd;
434 bfd_byte *loc;
435 bfd_vma sym_value, phys_page, phys_addr;
437 /* Massage our args to the form they really have. */
438 stub_entry = (struct elf32_m68hc11_stub_hash_entry *) gen_entry;
439 info = (struct bfd_link_info *) in_arg;
441 htab = m68hc11_elf_hash_table (info);
443 stub_sec = stub_entry->stub_sec;
445 /* Make a note of the offset within the stubs for this entry. */
446 stub_entry->stub_offset = stub_sec->size;
447 stub_sec->size += 7;
448 loc = stub_sec->contents + stub_entry->stub_offset;
450 stub_bfd = stub_sec->owner;
452 /* Create the trampoline call stub:
454 ldy #%addr(symbol)
455 call %page(symbol), __trampoline
458 sym_value = (stub_entry->target_value
459 + stub_entry->target_section->output_offset
460 + stub_entry->target_section->output_section->vma);
461 phys_addr = m68hc11_phys_addr (&htab->pinfo, sym_value);
462 phys_page = m68hc11_phys_page (&htab->pinfo, sym_value);
464 /* ldy #%page(sym) */
465 bfd_put_8 (stub_bfd, 0xCD, loc);
466 bfd_put_16 (stub_bfd, phys_addr, loc + 1);
467 loc += 3;
469 /* call %page(sym), __trampoline */
470 bfd_put_8 (stub_bfd, 0x4a, loc);
471 bfd_put_16 (stub_bfd, htab->pinfo.trampoline_addr, loc + 1);
472 bfd_put_8 (stub_bfd, phys_page, loc + 3);
474 return TRUE;
477 /* As above, but don't actually build the stub. Just bump offset so
478 we know stub section sizes. */
480 static bfd_boolean
481 m68hc12_elf_size_one_stub (struct bfd_hash_entry *gen_entry,
482 void *in_arg ATTRIBUTE_UNUSED)
484 struct elf32_m68hc11_stub_hash_entry *stub_entry;
486 /* Massage our args to the form they really have. */
487 stub_entry = (struct elf32_m68hc11_stub_hash_entry *) gen_entry;
489 stub_entry->stub_sec->size += 7;
490 return TRUE;
493 /* Create a 68HC12 ELF linker hash table. */
495 static struct bfd_link_hash_table *
496 m68hc12_elf_bfd_link_hash_table_create (bfd *abfd)
498 struct m68hc11_elf_link_hash_table *ret;
500 ret = m68hc11_elf_hash_table_create (abfd);
501 if (ret == (struct m68hc11_elf_link_hash_table *) NULL)
502 return NULL;
504 ret->size_one_stub = m68hc12_elf_size_one_stub;
505 ret->build_one_stub = m68hc12_elf_build_one_stub;
507 return &ret->root.root;
510 static bfd_boolean
511 m68hc12_elf_set_mach_from_flags (bfd *abfd)
513 flagword flags = elf_elfheader (abfd)->e_flags;
515 switch (flags & EF_M68HC11_MACH_MASK)
517 case EF_M68HC12_MACH:
518 bfd_default_set_arch_mach (abfd, bfd_arch_m68hc12, bfd_mach_m6812);
519 break;
520 case EF_M68HCS12_MACH:
521 bfd_default_set_arch_mach (abfd, bfd_arch_m68hc12, bfd_mach_m6812s);
522 break;
523 case EF_M68HC11_GENERIC:
524 bfd_default_set_arch_mach (abfd, bfd_arch_m68hc12,
525 bfd_mach_m6812_default);
526 break;
527 default:
528 return FALSE;
530 return TRUE;
533 /* Specific sections:
534 - The .page0 is a data section that is mapped in [0x0000..0x00FF].
535 Page0 accesses are faster on the M68HC12.
536 - The .vectors is the section that represents the interrupt
537 vectors. */
538 static const struct bfd_elf_special_section elf32_m68hc12_special_sections[] =
540 { ".eeprom", 7, 0, SHT_PROGBITS, SHF_ALLOC + SHF_WRITE },
541 { ".page0", 6, 0, SHT_PROGBITS, SHF_ALLOC + SHF_WRITE },
542 { ".softregs", 9, 0, SHT_NOBITS, SHF_ALLOC + SHF_WRITE },
543 { ".vectors", 8, 0, SHT_PROGBITS, SHF_ALLOC },
544 { NULL, 0, 0, 0, 0 }
547 #define ELF_ARCH bfd_arch_m68hc12
548 #define ELF_MACHINE_CODE EM_68HC12
549 #define ELF_MAXPAGESIZE 0x1000
551 #define TARGET_BIG_SYM bfd_elf32_m68hc12_vec
552 #define TARGET_BIG_NAME "elf32-m68hc12"
554 #define elf_info_to_howto 0
555 #define elf_info_to_howto_rel m68hc11_info_to_howto_rel
556 #define elf_backend_gc_mark_hook elf32_m68hc11_gc_mark_hook
557 #define elf_backend_gc_sweep_hook elf32_m68hc11_gc_sweep_hook
558 #define elf_backend_check_relocs elf32_m68hc11_check_relocs
559 #define elf_backend_relocate_section elf32_m68hc11_relocate_section
560 #define elf_backend_object_p m68hc12_elf_set_mach_from_flags
561 #define elf_backend_final_write_processing 0
562 #define elf_backend_can_gc_sections 1
563 #define elf_backend_special_sections elf32_m68hc12_special_sections
564 #define elf_backend_post_process_headers elf32_m68hc11_post_process_headers
565 #define elf_backend_add_symbol_hook elf32_m68hc11_add_symbol_hook
567 #define bfd_elf32_bfd_link_hash_table_create \
568 m68hc12_elf_bfd_link_hash_table_create
569 #define bfd_elf32_bfd_link_hash_table_free \
570 m68hc11_elf_bfd_link_hash_table_free
571 #define bfd_elf32_bfd_merge_private_bfd_data \
572 _bfd_m68hc11_elf_merge_private_bfd_data
573 #define bfd_elf32_bfd_set_private_flags _bfd_m68hc11_elf_set_private_flags
574 #define bfd_elf32_bfd_print_private_bfd_data \
575 _bfd_m68hc11_elf_print_private_bfd_data
577 #include "elf32-target.h"