1/* Freescale S12Z-specific support for 32-bit ELF
2   Copyright (C) 1999-2022 Free Software Foundation, Inc.
3   (Heavily copied from the D10V port by Martin Hunt (hunt@cygnus.com))
4
5   This file is part of BFD, the Binary File Descriptor library.
6
7   This program is free software; you can redistribute it and/or modify
8   it under the terms of the GNU General Public License as published by
9   the Free Software Foundation; either version 3 of the License, or
10   (at your option) any later version.
11
12   This program is distributed in the hope that it will be useful,
13   but WITHOUT ANY WARRANTY; without even the implied warranty of
14   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15   GNU General Public License for more details.
16
17   You should have received a copy of the GNU General Public License
18   along with this program; if not, write to the Free Software
19   Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
20   MA 02110-1301, USA.  */
21
22#include "sysdep.h"
23#include "bfd.h"
24#include "bfdlink.h"
25#include "libbfd.h"
26#include "elf-bfd.h"
27
28#include "elf/s12z.h"
29
30/* All users of this file have bfd_octets_per_byte (abfd, sec) == 1.  */
31#define OCTETS_PER_BYTE(ABFD, SEC) 1
32
33/* Relocation functions.  */
34static reloc_howto_type *bfd_elf32_bfd_reloc_type_lookup
35  (bfd *, bfd_reloc_code_real_type);
36static bool s12z_info_to_howto_rel
37  (bfd *, arelent *, Elf_Internal_Rela *);
38
39static bfd_reloc_status_type
40opru18_reloc (bfd *abfd, arelent *reloc_entry, struct bfd_symbol *symbol,
41		    void *data, asection *input_section ATTRIBUTE_UNUSED,
42		    bfd *output ATTRIBUTE_UNUSED, char **msg ATTRIBUTE_UNUSED)
43{
44  /* This reloc is used for 18 bit General Operand Addressing Postbyte in the
45     INST opru18 form.  This is an 18 bit reloc, but the most significant bit
46     is shifted one place to the left of where it would normally be.  See
47     Appendix A.4 of the S12Z reference manual.  */
48
49  bfd_size_type octets = (reloc_entry->address
50			  * OCTETS_PER_BYTE (abfd, input_section));
51  bfd_vma result = bfd_get_24 (abfd, (unsigned char *) data + octets);
52  bfd_vma val = bfd_asymbol_value (symbol);
53
54  /* Keep the wanted bits and discard the rest.  */
55  result &= 0xFA0000;
56
57  val += symbol->section->output_section->vma;
58  val += symbol->section->output_offset;
59
60  /* The lowest 17 bits are copied verbatim.  */
61  result |= val & 0x1FFFF;
62
63  /* The 18th bit is put into the 19th position.  */
64  result |= (val & 0x020000) << 1;
65
66  bfd_put_24 (abfd, result, (unsigned char *) data + octets);
67
68  return bfd_reloc_ok;
69}
70
71
72static bfd_reloc_status_type
73shift_addend_reloc (bfd *abfd, arelent *reloc_entry, struct bfd_symbol *symbol ATTRIBUTE_UNUSED,
74		    void *data ATTRIBUTE_UNUSED, asection *input_section ATTRIBUTE_UNUSED,
75		    bfd *output ATTRIBUTE_UNUSED, char **msg ATTRIBUTE_UNUSED)
76{
77  /* This is a really peculiar reloc, which is done for compatibility
78     with the Freescale toolchain.
79
80     That toolchain appears to (ab)use the lowest 15 bits of the addend for
81     the purpose of holding flags.  The purpose of these flags are unknown.
82     So in this function, when writing the bfd we left shift the addend by
83     15, and when reading we right shift it by 15 (discarding the lower bits).
84
85     This allows the linker to work with object files generated by Freescale,
86     as well as by Gas.  */
87
88  if (abfd->is_linker_input)
89    reloc_entry->addend >>= 15;
90  else
91    reloc_entry->addend <<= 15;
92
93  return bfd_reloc_continue;
94}
95
96#define USE_REL	0
97
98static reloc_howto_type elf_s12z_howto_table[] =
99{
100  /* This reloc does nothing.  */
101  HOWTO (R_S12Z_NONE,	/* type */
102	 0,			/* rightshift */
103	 0,			/* size */
104	 0,			/* bitsize */
105	 false,			/* pc_relative */
106	 0,			/* bitpos */
107	 complain_overflow_dont,/* complain_on_overflow */
108	 bfd_elf_generic_reloc,	/* special_function */
109	 "R_S12Z_NONE",	/* name */
110	 false,			/* partial_inplace */
111	 0,			/* src_mask */
112	 0,			/* dst_mask */
113	 false),		/* pcrel_offset */
114
115  /* A 24 bit absolute relocation emitted by the OPR mode operands  */
116  HOWTO (R_S12Z_OPR,        /* type */
117	 0,			/* rightshift */
118	 3,			/* size */
119	 24,			/* bitsize */
120	 false,			/* pc_relative */
121	 0,			/* bitpos */
122	 complain_overflow_bitfield,	/* complain_on_overflow */
123	 shift_addend_reloc,
124	 "R_S12Z_OPR",	/* name */
125	 false,			/* partial_inplace */
126	 0x00ffffff,            /* src_mask */
127	 0x00ffffff,		/* dst_mask */
128	 false),		/* pcrel_offset */
129
130  /* The purpose of this reloc is not known */
131  HOWTO (R_S12Z_UKNWN_2,	/* type */
132	 0,			/* rightshift */
133	 0,			/* size */
134	 0,			/* bitsize */
135	 false,			/* pc_relative */
136	 0,			/* bitpos */
137	 complain_overflow_dont,/* complain_on_overflow */
138	 bfd_elf_generic_reloc,	/* special_function */
139	 "R_S12Z_UKNWN_2",	/* name */
140	 false,			/* partial_inplace */
141	 0,			/* src_mask */
142	 0,			/* dst_mask */
143	 false),		/* pcrel_offset */
144
145  /* A 15 bit PC-rel relocation */
146  HOWTO (R_S12Z_PCREL_7_15,	/* type */
147	 0,			/* rightshift */
148	 2,			/* size */
149	 15,			/* bitsize */
150	 true,			/* pc_relative */
151	 0,			/* bitpos */
152	 complain_overflow_bitfield,	/* complain_on_overflow */
153	 shift_addend_reloc,
154	 "R_S12Z_PCREL_7_15",	/* name */
155	 false,			/* partial_inplace */
156	 0x00,                  /* src_mask */
157	 0x007fff,		/* dst_mask */
158	 true),			/* pcrel_offset */
159
160  /* A 24 bit absolute relocation emitted by EXT24 mode operands */
161  HOWTO (R_S12Z_EXT24,        /* type */
162	 0,			/* rightshift */
163	 3,			/* size */
164	 24,			/* bitsize */
165	 false,			/* pc_relative */
166	 0,			/* bitpos */
167	 complain_overflow_bitfield,	/* complain_on_overflow */
168	 bfd_elf_generic_reloc,	/* special_function */
169	 "R_S12Z_EXT24",	/* name */
170	 false,			/* partial_inplace */
171	 0x00000000,            /* src_mask */
172	 0x00ffffff,		/* dst_mask */
173	 false),		/* pcrel_offset */
174
175  /* An 18 bit absolute relocation */
176  HOWTO (R_S12Z_EXT18,        /* type */
177	 0,			/* rightshift */
178	 3,			/* size */
179	 18,			/* bitsize */
180	 false,			/* pc_relative */
181	 0,			/* bitpos */
182	 complain_overflow_bitfield,	/* complain_on_overflow */
183	 opru18_reloc,	        /* special_function */
184	 "R_S12Z_EXT18",	/* name */
185	 false,			/* partial_inplace */
186	 0x00000000,            /* src_mask */
187	 0x0005ffff,		/* dst_mask */
188	 false),		/* pcrel_offset */
189
190  /* A 32 bit absolute relocation.   This kind of relocation is
191     schizophrenic - Although they appear in sections named .rela.debug.*
192     in some sections they behave as RELA relocs, but in others they have
193     an added of zero and behave as REL.
194
195     It is not recommended that new code  emits this reloc.   It is here
196     only to support existing elf files generated by third party
197     applications.  */
198
199  HOWTO (R_S12Z_CW32,        /* type */
200	 0,			/* rightshift */
201	 4,			/* size */
202	 32,			/* bitsize */
203	 false,			/* pc_relative */
204	 0,			/* bitpos */
205	 complain_overflow_bitfield,	/* complain_on_overflow */
206	 bfd_elf_generic_reloc,	/* special_function */
207	 "R_S12Z_CW32",	/* name */
208	 false,			/* partial_inplace */
209	 0xffffffff,            /* src_mask */
210	 0xffffffff,		/* dst_mask */
211	 false),		/* pcrel_offset */
212
213  /* A 32 bit absolute relocation  */
214  HOWTO (R_S12Z_EXT32,        /* type */
215	 0,			/* rightshift */
216	 4,			/* size */
217	 32,			/* bitsize */
218	 false,			/* pc_relative */
219	 0,			/* bitpos */
220	 complain_overflow_bitfield,	/* complain_on_overflow */
221	 bfd_elf_generic_reloc,	/* special_function */
222	 "R_S12Z_EXT32",	/* name */
223	 false,			/* partial_inplace */
224	 0x00000000,            /* src_mask */
225	 0xffffffff,		/* dst_mask */
226	 false),		/* pcrel_offset */
227};
228
229/* Map BFD reloc types to S12Z ELF reloc types.  */
230
231struct s12z_reloc_map
232{
233  bfd_reloc_code_real_type bfd_reloc_val;
234  unsigned char elf_reloc_val;
235};
236
237static const struct s12z_reloc_map s12z_reloc_map[] =
238{
239  /* bfd reloc val */  /* elf reloc val */
240  {BFD_RELOC_NONE,     R_S12Z_NONE},
241  {BFD_RELOC_32,       R_S12Z_EXT32},
242  {BFD_RELOC_24,       R_S12Z_EXT24},
243  {BFD_RELOC_16_PCREL, R_S12Z_PCREL_7_15},
244  {BFD_RELOC_S12Z_OPR, R_S12Z_OPR}
245};
246
247static reloc_howto_type *
248bfd_elf32_bfd_reloc_type_lookup (bfd *abfd ATTRIBUTE_UNUSED,
249				 bfd_reloc_code_real_type code)
250{
251  unsigned int i;
252
253  for (i = 0;
254       i < sizeof (s12z_reloc_map) / sizeof (struct s12z_reloc_map);
255       i++)
256    {
257      if (s12z_reloc_map[i].bfd_reloc_val == code)
258	{
259	  return &elf_s12z_howto_table[s12z_reloc_map[i].elf_reloc_val];
260	}
261    }
262
263  printf ("%s:%d Not found type %d\n", __FILE__, __LINE__, code);
264
265  return NULL;
266}
267
268static reloc_howto_type *
269bfd_elf32_bfd_reloc_name_lookup (bfd *abfd ATTRIBUTE_UNUSED,
270				 const char *r_name)
271{
272  unsigned int i;
273
274  for (i = 0;
275       i < (sizeof (elf_s12z_howto_table)
276	    / sizeof (elf_s12z_howto_table[0]));
277       i++)
278    if (elf_s12z_howto_table[i].name != NULL
279	&& strcasecmp (elf_s12z_howto_table[i].name, r_name) == 0)
280      return &elf_s12z_howto_table[i];
281
282  return NULL;
283}
284
285/* Set the howto pointer for an S12Z ELF reloc.  */
286
287static bool
288s12z_info_to_howto_rel (bfd *abfd,
289			  arelent *cache_ptr, Elf_Internal_Rela *dst)
290{
291  unsigned int  r_type = ELF32_R_TYPE (dst->r_info);
292
293  if (r_type >= (unsigned int) R_S12Z_max)
294    {
295      /* xgettext:c-format */
296      _bfd_error_handler (_("%pB: unsupported relocation type %#x"),
297			  abfd, r_type);
298      bfd_set_error (bfd_error_bad_value);
299      return false;
300    }
301
302  cache_ptr->howto = &elf_s12z_howto_table[r_type];
303  return true;
304}
305
306static bool
307s12z_elf_set_mach_from_flags (bfd *abfd)
308{
309  bfd_default_set_arch_mach (abfd, bfd_arch_s12z, 0);
310
311  return true;
312}
313
314#define ELF_ARCH		bfd_arch_s12z
315#define ELF_MACHINE_CODE	EM_S12Z
316#define ELF_MAXPAGESIZE		0x1000
317
318#define TARGET_BIG_SYM		s12z_elf32_vec
319#define TARGET_BIG_NAME		"elf32-s12z"
320
321#define elf_info_to_howto			NULL
322#define elf_info_to_howto_rel			s12z_info_to_howto_rel
323#define elf_backend_object_p			s12z_elf_set_mach_from_flags
324
325#include "elf32-target.h"
326