ATMEL AVR microcontroller support.

1 files changed, 963 insertions, 0 deletions

diff --git a/bfd/elf32-avr.c b/bfd/elf32-avr.c
new file mode 100644
index 0000000..c64ab28
--- /dev/null
+++ b/bfd/elf32-avr.c
@@ -0,0 +1,963 @@
+/* AVR-specific support for 32-bit ELF
+   Copyright (C) 1999, 2000 Free Software Foundation, Inc.
+   Contributed by Denis Chertykov <denisc@overta.ru>
+
+This file is part of BFD, the Binary File Descriptor library.
+
+This program is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
+
+
+#include "bfd.h"
+#include "sysdep.h"
+#include "libbfd.h"
+#include "elf-bfd.h"
+#include "elf/avr.h"
+
+static reloc_howto_type *bfd_elf32_bfd_reloc_type_lookup
+  PARAMS ((bfd *abfd, bfd_reloc_code_real_type code));
+static void avr_info_to_howto_rela
+  PARAMS ((bfd *, arelent *, Elf32_Internal_Rela *));
+static asection *elf32_avr_gc_mark_hook
+  PARAMS ((bfd *, struct bfd_link_info *, Elf_Internal_Rela *,
+	   struct elf_link_hash_entry *, Elf_Internal_Sym *));
+static boolean elf32_avr_gc_sweep_hook
+  PARAMS ((bfd *, struct bfd_link_info *, asection *,
+	   const Elf_Internal_Rela *));
+static boolean elf32_avr_check_relocs
+  PARAMS ((bfd *, struct bfd_link_info *, asection *,
+	   const Elf_Internal_Rela *));
+static bfd_reloc_status_type avr_final_link_relocate
+  PARAMS ((reloc_howto_type *, bfd *, asection *, bfd_byte *,
+	   Elf_Internal_Rela *, bfd_vma));
+static boolean elf32_avr_relocate_section
+  PARAMS ((bfd *, struct bfd_link_info *, bfd *, asection *, bfd_byte *,
+	   Elf_Internal_Rela *, Elf_Internal_Sym *, asection **));
+static void bfd_elf_avr_final_write_processing PARAMS ((bfd *, boolean));
+static boolean elf32_avr_object_p PARAMS ((bfd *));
+
+
+/* Use RELA instead of REL */
+#undef USE_REL
+
+static reloc_howto_type elf_avr_howto_table[] =
+{
+  HOWTO (R_AVR_NONE,		/* type */
+	 0,			/* rightshift */
+	 2,			/* size (0 = byte, 1 = short, 2 = long) */
+	 32,			/* bitsize */
+	 false,			/* pc_relative */
+	 0,			/* bitpos */
+	 complain_overflow_bitfield, /* complain_on_overflow */
+	 bfd_elf_generic_reloc,	/* special_function */
+	 "R_AVR_NONE",		/* name */
+	 false,			/* partial_inplace */
+	 0,			/* src_mask */
+	 0,			/* dst_mask */
+	 false),		/* pcrel_offset */
+
+  HOWTO (R_AVR_32,		/* type */
+	 0,			/* rightshift */
+	 2,			/* size (0 = byte, 1 = short, 2 = long) */
+	 32,			/* bitsize */
+	 false,			/* pc_relative */
+	 0,			/* bitpos */
+	 complain_overflow_bitfield, /* complain_on_overflow */
+	 bfd_elf_generic_reloc,	/* special_function */
+	 "R_AVR_32",		/* name */
+	 false,			/* partial_inplace */
+	 0xffffffff,		/* src_mask */
+	 0xffffffff,		/* dst_mask */
+	 false),		/* pcrel_offset */
+
+  /* A 7 bit PC relative relocation.  */
+  HOWTO (R_AVR_7_PCREL,		/* type */
+	 1,			/* rightshift */
+	 1,			/* size (0 = byte, 1 = short, 2 = long) */
+	 7,			/* bitsize */
+	 true,			/* pc_relative */
+	 3,			/* bitpos */
+	 complain_overflow_bitfield, /* complain_on_overflow */
+	 bfd_elf_generic_reloc, /* special_function */
+	 "R_AVR_7_PCREL",	/* name */
+	 false,			/* partial_inplace */
+	 0xffff,		/* src_mask */
+	 0xffff,		/* dst_mask */
+	 true),			/* pcrel_offset */
+
+  /* A 13 bit PC relative relocation.  */
+  HOWTO (R_AVR_13_PCREL,	/* type */
+	 1,			/* rightshift */
+	 1,			/* size (0 = byte, 1 = short, 2 = long) */
+	 13,			/* bitsize */
+	 true,			/* pc_relative */
+	 0,			/* bitpos */
+	 complain_overflow_bitfield, /* complain_on_overflow */
+	 bfd_elf_generic_reloc, /* special_function */
+	 "R_AVR_13_PCREL",	/* name */
+	 false,			/* partial_inplace */
+	 0xfff,			/* src_mask */
+	 0xfff,			/* dst_mask */
+	 true),			/* pcrel_offset */
+
+  /* A 16 bit absolute relocation.  */
+  HOWTO (R_AVR_16,		/* type */
+	 0,			/* rightshift */
+	 1,			/* size (0 = byte, 1 = short, 2 = long) */
+	 16,			/* bitsize */
+	 false,			/* pc_relative */
+	 0,			/* bitpos */
+	 complain_overflow_dont, /* complain_on_overflow */
+	 bfd_elf_generic_reloc,	/* special_function */
+	 "R_AVR_16",		/* name */
+	 false,			/* partial_inplace */
+	 0xffff,		/* src_mask */
+	 0xffff,		/* dst_mask */
+	 false),		/* pcrel_offset */
+
+  /* A 16 bit absolute relocation for command address.  */
+  HOWTO (R_AVR_16_PM,		/* type */
+	 1,			/* rightshift */
+	 1,			/* size (0 = byte, 1 = short, 2 = long) */
+	 16,			/* bitsize */
+	 false,			/* pc_relative */
+	 0,			/* bitpos */
+	 complain_overflow_bitfield, /* complain_on_overflow */
+	 bfd_elf_generic_reloc,	/* special_function */
+	 "R_AVR_16_PM",		/* name */
+	 false,			/* partial_inplace */
+	 0xffff,		/* src_mask */
+	 0xffff,		/* dst_mask */
+	 false),		/* pcrel_offset */
+  /* A low 8 bit absolute relocation of 16 bit address.
+     For LDI command.  */
+  HOWTO (R_AVR_LO8_LDI,		/* type */
+	 0,			/* rightshift */
+	 1,			/* size (0 = byte, 1 = short, 2 = long) */
+	 8,			/* bitsize */
+	 false,			/* pc_relative */
+	 0,			/* bitpos */
+	 complain_overflow_dont, /* complain_on_overflow */
+	 bfd_elf_generic_reloc,	/* special_function */
+	 "R_AVR_LO8_LDI",	/* name */
+	 false,			/* partial_inplace */
+	 0xffff,		/* src_mask */
+	 0xffff,		/* dst_mask */
+	 false),		/* pcrel_offset */
+  /* A high 8 bit absolute relocation of 16 bit address.
+     For LDI command.  */
+  HOWTO (R_AVR_HI8_LDI,		/* type */
+	 8,			/* rightshift */
+	 1,			/* size (0 = byte, 1 = short, 2 = long) */
+	 8,			/* bitsize */
+	 false,			/* pc_relative */
+	 0,			/* bitpos */
+	 complain_overflow_dont, /* complain_on_overflow */
+	 bfd_elf_generic_reloc,	/* special_function */
+	 "R_AVR_HI8_LDI",	/* name */
+	 false,			/* partial_inplace */
+	 0xffff,		/* src_mask */
+	 0xffff,		/* dst_mask */
+	 false),		/* pcrel_offset */
+  /* A high 6 bit absolute relocation of 22 bit address.
+     For LDI command.  */
+  HOWTO (R_AVR_HH8_LDI,		/* type */
+	 16,			/* rightshift */
+	 1,			/* size (0 = byte, 1 = short, 2 = long) */
+	 8,			/* bitsize */
+	 false,			/* pc_relative */
+	 0,			/* bitpos */
+	 complain_overflow_dont, /* complain_on_overflow */
+	 bfd_elf_generic_reloc,	/* special_function */
+	 "R_AVR_HH8_LDI",	/* name */
+	 false,			/* partial_inplace */
+	 0xffff,		/* src_mask */
+	 0xffff,		/* dst_mask */
+	 false),		/* pcrel_offset */
+  /* A negative low 8 bit absolute relocation of 16 bit address.
+     For LDI command.  */
+  HOWTO (R_AVR_LO8_LDI_NEG,	/* type */
+	 0,			/* rightshift */
+	 1,			/* size (0 = byte, 1 = short, 2 = long) */
+	 8,			/* bitsize */
+	 false,			/* pc_relative */
+	 0,			/* bitpos */
+	 complain_overflow_dont, /* complain_on_overflow */
+	 bfd_elf_generic_reloc,	/* special_function */
+	 "R_AVR_LO8_LDI_NEG",	/* name */
+	 false,			/* partial_inplace */
+	 0xffff,		/* src_mask */
+	 0xffff,		/* dst_mask */
+	 false),		/* pcrel_offset */
+  /* A hegative high 8 bit absolute relocation of 16 bit address.
+     For LDI command.  */
+  HOWTO (R_AVR_HI8_LDI_NEG,	/* type */
+	 8,			/* rightshift */
+	 1,			/* size (0 = byte, 1 = short, 2 = long) */
+	 8,			/* bitsize */
+	 false,			/* pc_relative */
+	 0,			/* bitpos */
+	 complain_overflow_dont, /* complain_on_overflow */
+	 bfd_elf_generic_reloc,	/* special_function */
+	 "R_AVR_HI8_LDI_NEG",	/* name */
+	 false,			/* partial_inplace */
+	 0xffff,		/* src_mask */
+	 0xffff,		/* dst_mask */
+	 false),		/* pcrel_offset */
+  /* A hegative high 6 bit absolute relocation of 22 bit address.
+     For LDI command.  */
+  HOWTO (R_AVR_HH8_LDI_NEG,	/* type */
+	 16,			/* rightshift */
+	 1,			/* size (0 = byte, 1 = short, 2 = long) */
+	 8,			/* bitsize */
+	 false,			/* pc_relative */
+	 0,			/* bitpos */
+	 complain_overflow_dont, /* complain_on_overflow */
+	 bfd_elf_generic_reloc,	/* special_function */
+	 "R_AVR_HH8_LDI_NEG",	/* name */
+	 false,			/* partial_inplace */
+	 0xffff,		/* src_mask */
+	 0xffff,		/* dst_mask */
+	 false),		/* pcrel_offset */
+  /* A low 8 bit absolute relocation of 24 bit program memory address.
+     For LDI command.  */
+  HOWTO (R_AVR_LO8_LDI_PM,	/* type */
+	 1,			/* rightshift */
+	 1,			/* size (0 = byte, 1 = short, 2 = long) */
+	 8,			/* bitsize */
+	 false,			/* pc_relative */
+	 0,			/* bitpos */
+	 complain_overflow_dont, /* complain_on_overflow */
+	 bfd_elf_generic_reloc,	/* special_function */
+	 "R_AVR_LO8_LDI_PM",	/* name */
+	 false,			/* partial_inplace */
+	 0xffff,		/* src_mask */
+	 0xffff,		/* dst_mask */
+	 false),		/* pcrel_offset */
+  /* A high 8 bit absolute relocation of 16 bit program memory address.
+     For LDI command.  */
+  HOWTO (R_AVR_HI8_LDI_PM,	/* type */
+	 9,			/* rightshift */
+	 1,			/* size (0 = byte, 1 = short, 2 = long) */
+	 8,			/* bitsize */
+	 false,			/* pc_relative */
+	 0,			/* bitpos */
+	 complain_overflow_dont, /* complain_on_overflow */
+	 bfd_elf_generic_reloc,	/* special_function */
+	 "R_AVR_HI8_LDI_PM",	/* name */
+	 false,			/* partial_inplace */
+	 0xffff,		/* src_mask */
+	 0xffff,		/* dst_mask */
+	 false),		/* pcrel_offset */
+  /* A high 8 bit absolute relocation of 24 bit program memory address.
+     For LDI command.  */
+  HOWTO (R_AVR_HH8_LDI_PM,	/* type */
+	 17,			/* rightshift */
+	 1,			/* size (0 = byte, 1 = short, 2 = long) */
+	 8,			/* bitsize */
+	 false,			/* pc_relative */
+	 0,			/* bitpos */
+	 complain_overflow_dont, /* complain_on_overflow */
+	 bfd_elf_generic_reloc,	/* special_function */
+	 "R_AVR_HH8_LDI_PM",	/* name */
+	 false,			/* partial_inplace */
+	 0xffff,		/* src_mask */
+	 0xffff,		/* dst_mask */
+	 false),		/* pcrel_offset */
+  /* A low 8 bit absolute relocation of a negative 24 bit
+     program memory address.  For LDI command.  */
+  HOWTO (R_AVR_LO8_LDI_PM_NEG,	/* type */
+	 1,			/* rightshift */
+	 1,			/* size (0 = byte, 1 = short, 2 = long) */
+	 8,			/* bitsize */
+	 false,			/* pc_relative */
+	 0,			/* bitpos */
+	 complain_overflow_dont, /* complain_on_overflow */
+	 bfd_elf_generic_reloc,	/* special_function */
+	 "R_AVR_LO8_LDI_PM_NEG", /* name */
+	 false,			/* partial_inplace */
+	 0xffff,		/* src_mask */
+	 0xffff,		/* dst_mask */
+	 false),		/* pcrel_offset */
+  /* A high 8 bit absolute relocation of a negative 16 bit
+     program memory address.  For LDI command.  */
+  HOWTO (R_AVR_HI8_LDI_PM_NEG,	/* type */
+	 9,			/* rightshift */
+	 1,			/* size (0 = byte, 1 = short, 2 = long) */
+	 8,			/* bitsize */
+	 false,			/* pc_relative */
+	 0,			/* bitpos */
+	 complain_overflow_dont, /* complain_on_overflow */
+	 bfd_elf_generic_reloc,	/* special_function */
+	 "R_AVR_HI8_LDI_PM_NEG", /* name */
+	 false,			/* partial_inplace */
+	 0xffff,		/* src_mask */
+	 0xffff,		/* dst_mask */
+	 false),		/* pcrel_offset */
+  /* A high 8 bit absolute relocation of a negative 24 bit
+     program memory address.  For LDI command.  */
+  HOWTO (R_AVR_HH8_LDI_PM_NEG,	/* type */
+	 17,			/* rightshift */
+	 1,			/* size (0 = byte, 1 = short, 2 = long) */
+	 8,			/* bitsize */
+	 false,			/* pc_relative */
+	 0,			/* bitpos */
+	 complain_overflow_dont, /* complain_on_overflow */
+	 bfd_elf_generic_reloc,	/* special_function */
+	 "R_AVR_HH8_LDI_PM_NEG", /* name */
+	 false,			/* partial_inplace */
+	 0xffff,		/* src_mask */
+	 0xffff,		/* dst_mask */
+	 false),		/* pcrel_offset */
+  /* Relocation for CALL command in ATmega.  */
+  HOWTO (R_AVR_CALL,		/* type */
+	 1,			/* rightshift */
+	 2,			/* size (0 = byte, 1 = short, 2 = long) */
+	 23,			/* bitsize */
+	 false,			/* pc_relative */
+	 0,			/* bitpos */
+	 complain_overflow_dont, /* complain_on_overflow */
+	 bfd_elf_generic_reloc,	/* special_function */
+	 "R_AVR_CALL",		/* name */
+	 false,			/* partial_inplace */
+	 0xffffffff,		/* src_mask */
+	 0xffffffff,		/* dst_mask */
+	 false)			/* pcrel_offset */
+};
+
+/* Map BFD reloc types to AVR ELF reloc types.  */
+
+struct avr_reloc_map
+{
+  bfd_reloc_code_real_type bfd_reloc_val;
+  unsigned int elf_reloc_val;
+};
+
+ static const struct avr_reloc_map avr_reloc_map[] =
+{
+  { BFD_RELOC_NONE,                 R_AVR_NONE },
+  { BFD_RELOC_32,                   R_AVR_32 },
+  { BFD_RELOC_AVR_7_PCREL,          R_AVR_7_PCREL },
+  { BFD_RELOC_AVR_13_PCREL,         R_AVR_13_PCREL },
+  { BFD_RELOC_16,                   R_AVR_16 },
+  { BFD_RELOC_AVR_16_PM,            R_AVR_16_PM },
+  { BFD_RELOC_AVR_LO8_LDI,          R_AVR_LO8_LDI},
+  { BFD_RELOC_AVR_HI8_LDI,          R_AVR_HI8_LDI },
+  { BFD_RELOC_AVR_HH8_LDI,          R_AVR_HH8_LDI },
+  { BFD_RELOC_AVR_LO8_LDI_NEG,      R_AVR_LO8_LDI_NEG },
+  { BFD_RELOC_AVR_HI8_LDI_NEG,      R_AVR_HI8_LDI_NEG },
+  { BFD_RELOC_AVR_HH8_LDI_NEG,      R_AVR_HH8_LDI_NEG },
+  { BFD_RELOC_AVR_LO8_LDI_PM,       R_AVR_LO8_LDI_PM },
+  { BFD_RELOC_AVR_HI8_LDI_PM,       R_AVR_HI8_LDI_PM },
+  { BFD_RELOC_AVR_HH8_LDI_PM,       R_AVR_HH8_LDI_PM },
+  { BFD_RELOC_AVR_LO8_LDI_PM_NEG,   R_AVR_LO8_LDI_PM_NEG },
+  { BFD_RELOC_AVR_HI8_LDI_PM_NEG,   R_AVR_HI8_LDI_PM_NEG },
+  { BFD_RELOC_AVR_HH8_LDI_PM_NEG,   R_AVR_HH8_LDI_PM_NEG },
+  { BFD_RELOC_AVR_CALL,             R_AVR_CALL }
+};
+
+static reloc_howto_type *
+bfd_elf32_bfd_reloc_type_lookup (abfd, code)
+     bfd *abfd;
+     bfd_reloc_code_real_type code;
+{
+  unsigned int i;
+
+  for (i = 0;
+       i < sizeof (avr_reloc_map) / sizeof (struct avr_reloc_map);
+       i++)
+    {
+      if (avr_reloc_map[i].bfd_reloc_val == code)
+	return &elf_avr_howto_table[avr_reloc_map[i].elf_reloc_val];
+    }
+
+  return NULL;
+}
+
+/* Set the howto pointer for an AVR ELF reloc.  */
+
+static void
+avr_info_to_howto_rela (abfd, cache_ptr, dst)
+     bfd *abfd;
+     arelent *cache_ptr;
+     Elf32_Internal_Rela *dst;
+{
+  unsigned int r_type;
+
+  r_type = ELF32_R_TYPE (dst->r_info);
+  BFD_ASSERT (r_type < (unsigned int) R_AVR_max);
+  cache_ptr->howto = &elf_avr_howto_table[r_type];
+}
+
+static asection *
+elf32_avr_gc_mark_hook (abfd, info, rel, h, sym)
+     bfd *abfd;
+     struct bfd_link_info *info;
+     Elf_Internal_Rela *rel;
+     struct elf_link_hash_entry *h;
+     Elf_Internal_Sym *sym;
+{
+  if (h != NULL)
+    {
+      switch (ELF32_R_TYPE (rel->r_info))
+	{
+	default:
+	  switch (h->root.type)
+	    {
+	    case bfd_link_hash_defined:
+	    case bfd_link_hash_defweak:
+	      return h->root.u.def.section;
+
+	    case bfd_link_hash_common:
+	      return h->root.u.c.p->section;
+
+	    default:
+	      break;
+	    }
+	}
+    }
+  else
+    {
+      if (!(elf_bad_symtab (abfd)
+	    && ELF_ST_BIND (sym->st_info) != STB_LOCAL)
+	  && !((sym->st_shndx <= 0 || sym->st_shndx >= SHN_LORESERVE)
+	       && sym->st_shndx != SHN_COMMON))
+	{
+	  return bfd_section_from_elf_index (abfd, sym->st_shndx);
+	}
+    }
+  return NULL;
+}
+
+static boolean
+elf32_avr_gc_sweep_hook (abfd, info, sec, relocs)
+     bfd *abfd;
+     struct bfd_link_info *info;
+     asection *sec;
+     const Elf_Internal_Rela *relocs;
+{
+  /* We don't use got and plt entries for avr.  */
+  return true;
+}
+
+/* Look through the relocs for a section during the first phase.
+   Since we don't do .gots or .plts, we just need to consider the
+   virtual table relocs for gc.  */
+
+static boolean
+elf32_avr_check_relocs (abfd, info, sec, relocs)
+     bfd *abfd;
+     struct bfd_link_info *info;
+     asection *sec;
+     const Elf_Internal_Rela *relocs;
+{
+  Elf_Internal_Shdr *symtab_hdr;
+  struct elf_link_hash_entry **sym_hashes, **sym_hashes_end;
+  const Elf_Internal_Rela *rel;
+  const Elf_Internal_Rela *rel_end;
+
+  if (info->relocateable)
+    return true;
+
+  symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
+  sym_hashes = elf_sym_hashes (abfd);
+  sym_hashes_end = sym_hashes + symtab_hdr->sh_size/sizeof(Elf32_External_Sym);
+  if (!elf_bad_symtab (abfd))
+    sym_hashes_end -= symtab_hdr->sh_info;
+
+  rel_end = relocs + sec->reloc_count;
+  for (rel = relocs; rel < rel_end; rel++)
+    {
+      struct elf_link_hash_entry *h;
+      unsigned long r_symndx;
+
+      r_symndx = ELF32_R_SYM (rel->r_info);
+      if (r_symndx < symtab_hdr->sh_info)
+        h = NULL;
+      else
+        h = sym_hashes[r_symndx - symtab_hdr->sh_info];
+    }
+
+  return true;
+}
+
+/* Perform a single relocation.  By default we use the standard BFD
+   routines, but a few relocs, we have to do them ourselves.  */
+
+static bfd_reloc_status_type
+avr_final_link_relocate (howto, input_bfd, input_section,
+			 contents, rel, relocation)
+     reloc_howto_type *  howto;
+     bfd *               input_bfd;
+     asection *          input_section;
+     bfd_byte *          contents;
+     Elf_Internal_Rela * rel;
+     bfd_vma             relocation;
+{
+  bfd_reloc_status_type r = bfd_reloc_ok;
+  bfd_vma               x;
+  bfd_signed_vma	srel;
+
+  switch (howto->type)
+    {
+    case R_AVR_7_PCREL:
+      contents += rel->r_offset;
+      srel = (bfd_signed_vma) relocation;
+      srel += rel->r_addend;
+      srel -= rel->r_offset;
+      srel -= 2;	/* Branch instructions add 2 to the PC... */
+      srel -= (input_section->output_section->vma +
+	       input_section->output_offset);
+
+      if (srel & 1)
+	return bfd_reloc_outofrange;
+      if (srel > ((1 << 7) - 1) || (srel < - (1 << 7)))
+	return bfd_reloc_overflow;
+      x = bfd_get_16 (input_bfd, contents);
+      x = (x & 0xfc07) | (((srel >> 1) << 3) & 0x3f8);
+      bfd_put_16 (input_bfd, x, contents);
+      break;
+
+    case R_AVR_13_PCREL:
+      contents   += rel->r_offset;
+      srel = (bfd_signed_vma) relocation;
+      srel += rel->r_addend;
+      srel -= rel->r_offset;
+      srel -= 2;	/* Branch instructions add 2 to the PC... */
+      srel -= (input_section->output_section->vma +
+	       input_section->output_offset);
+
+      if (srel & 1)
+	return bfd_reloc_outofrange;
+
+      /* AVR addresses commands as words.  */
+      srel >>= 1;
+
+      /* Check for overflow.  */
+      if (srel < -2048 || srel > 2047)
+	{
+	  /* Apply WRAPAROUND if possible.  */
+	  if (bfd_get_mach (input_bfd) == bfd_mach_avr2)
+	    {
+	      if (srel > 2047)
+		srel -= 4096;
+	      else
+		srel += 4096;
+	    }
+	  else
+	    return bfd_reloc_overflow;
+	}
+
+      x = bfd_get_16 (input_bfd, contents);
+      x = (x & 0xf000) | (srel & 0xfff);
+      bfd_put_16 (input_bfd, x, contents);
+      break;
+
+    case R_AVR_LO8_LDI:
+      contents += rel->r_offset;
+      srel = (bfd_signed_vma) relocation + rel->r_addend;
+      x = bfd_get_16 (input_bfd, contents);
+      x = (x & 0xf0f0) | (srel & 0xf) | ((srel << 4) & 0xf00);
+      bfd_put_16 (input_bfd, x, contents);
+      break;
+
+    case R_AVR_HI8_LDI:
+      contents += rel->r_offset;
+      srel = (bfd_signed_vma) relocation + rel->r_addend;
+      srel = (srel >> 8) & 0xff;
+      x = bfd_get_16 (input_bfd, contents);
+      x = (x & 0xf0f0) | (srel & 0xf) | ((srel << 4) & 0xf00);
+      bfd_put_16 (input_bfd, x, contents);
+      break;
+
+    case R_AVR_HH8_LDI:
+      contents += rel->r_offset;
+      srel = (bfd_signed_vma) relocation + rel->r_addend;
+      srel = (srel >> 16) & 0xff;
+      x = bfd_get_16 (input_bfd, contents);
+      x = (x & 0xf0f0) | (srel & 0xf) | ((srel << 4) & 0xf00);
+      bfd_put_16 (input_bfd, x, contents);
+      break;
+
+    case R_AVR_LO8_LDI_NEG:
+      contents += rel->r_offset;
+      srel = (bfd_signed_vma) relocation + rel->r_addend;
+      srel = -srel;
+      x = bfd_get_16 (input_bfd, contents);
+      x = (x & 0xf0f0) | (srel & 0xf) | ((srel << 4) & 0xf00);
+      bfd_put_16 (input_bfd, x, contents);
+      break;
+
+    case R_AVR_HI8_LDI_NEG:
+      contents += rel->r_offset;
+      srel = (bfd_signed_vma) relocation + rel->r_addend;
+      srel = -srel;
+      srel = (srel >> 8) & 0xff;
+      x = bfd_get_16 (input_bfd, contents);
+      x = (x & 0xf0f0) | (srel & 0xf) | ((srel << 4) & 0xf00);
+      bfd_put_16 (input_bfd, x, contents);
+      break;
+
+    case R_AVR_HH8_LDI_NEG:
+      contents += rel->r_offset;
+      srel = (bfd_signed_vma) relocation + rel->r_addend;
+      srel = -srel;
+      srel = (srel >> 16) & 0xff;
+      x = bfd_get_16 (input_bfd, contents);
+      x = (x & 0xf0f0) | (srel & 0xf) | ((srel << 4) & 0xf00);
+      bfd_put_16 (input_bfd, x, contents);
+      break;
+
+    case R_AVR_LO8_LDI_PM:
+      contents += rel->r_offset;
+      srel = (bfd_signed_vma) relocation + rel->r_addend;
+      if (srel & 1)
+	return bfd_reloc_outofrange;
+      srel = srel >> 1;
+      x = bfd_get_16 (input_bfd, contents);
+      x = (x & 0xf0f0) | (srel & 0xf) | ((srel << 4) & 0xf00);
+      bfd_put_16 (input_bfd, x, contents);
+      break;
+
+    case R_AVR_HI8_LDI_PM:
+      contents += rel->r_offset;
+      srel = (bfd_signed_vma) relocation + rel->r_addend;
+      if (srel & 1)
+	return bfd_reloc_outofrange;
+      srel = srel >> 1;
+      srel = (srel >> 8) & 0xff;
+      x = bfd_get_16 (input_bfd, contents);
+      x = (x & 0xf0f0) | (srel & 0xf) | ((srel << 4) & 0xf00);
+      bfd_put_16 (input_bfd, x, contents);
+      break;
+
+    case R_AVR_HH8_LDI_PM:
+      contents += rel->r_offset;
+      srel = (bfd_signed_vma) relocation + rel->r_addend;
+      if (srel & 1)
+	return bfd_reloc_outofrange;
+      srel = srel >> 1;
+      srel = (srel >> 16) & 0xff;
+      x = bfd_get_16 (input_bfd, contents);
+      x = (x & 0xf0f0) | (srel & 0xf) | ((srel << 4) & 0xf00);
+      bfd_put_16 (input_bfd, x, contents);
+      break;
+
+    case R_AVR_LO8_LDI_PM_NEG:
+      contents += rel->r_offset;
+      srel = (bfd_signed_vma) relocation + rel->r_addend;
+      srel = -srel;
+      if (srel & 1)
+	return bfd_reloc_outofrange;
+      srel = srel >> 1;
+      x = bfd_get_16 (input_bfd, contents);
+      x = (x & 0xf0f0) | (srel & 0xf) | ((srel << 4) & 0xf00);
+      bfd_put_16 (input_bfd, x, contents);
+      break;
+
+    case R_AVR_HI8_LDI_PM_NEG:
+      contents += rel->r_offset;
+      srel = (bfd_signed_vma) relocation + rel->r_addend;
+      srel = -srel;
+      if (srel & 1)
+	return bfd_reloc_outofrange;
+      srel = srel >> 1;
+      srel = (srel >> 8) & 0xff;
+      x = bfd_get_16 (input_bfd, contents);
+      x = (x & 0xf0f0) | (srel & 0xf) | ((srel << 4) & 0xf00);
+      bfd_put_16 (input_bfd, x, contents);
+      break;
+
+    case R_AVR_HH8_LDI_PM_NEG:
+      contents += rel->r_offset;
+      srel = (bfd_signed_vma) relocation + rel->r_addend;
+      srel = -srel;
+      if (srel & 1)
+	return bfd_reloc_outofrange;
+      srel = srel >> 1;
+      srel = (srel >> 16) & 0xff;
+      x = bfd_get_16 (input_bfd, contents);
+      x = (x & 0xf0f0) | (srel & 0xf) | ((srel << 4) & 0xf00);
+      bfd_put_16 (input_bfd, x, contents);
+      break;
+
+    case R_AVR_CALL:
+      contents += rel->r_offset;
+      srel = (bfd_signed_vma) relocation + rel->r_addend;
+      if (srel & 1)
+	return bfd_reloc_outofrange;
+      srel = srel >> 1;
+      x = bfd_get_16 (input_bfd, contents);
+      x |= ((srel & 0x10000) | ((srel << 3) & 0x1f00000)) >> 16;
+      bfd_put_16 (input_bfd, x, contents);
+      bfd_put_16 (input_bfd, srel & 0xffff, contents+2);
+      break;
+
+    default:
+      r = _bfd_final_link_relocate (howto, input_bfd, input_section,
+				    contents, rel->r_offset,
+				    relocation, rel->r_addend);
+    }
+
+  return r;
+}
+
+/* Relocate an AVR ELF section.  */
+static boolean
+elf32_avr_relocate_section (output_bfd, info, input_bfd, input_section,
+			    contents, relocs, local_syms, local_sections)
+     bfd *output_bfd;
+     struct bfd_link_info *info;
+     bfd *input_bfd;
+     asection *input_section;
+     bfd_byte *contents;
+     Elf_Internal_Rela *relocs;
+     Elf_Internal_Sym *local_syms;
+     asection **local_sections;
+{
+  Elf_Internal_Shdr *           symtab_hdr;
+  struct elf_link_hash_entry ** sym_hashes;
+  Elf_Internal_Rela *           rel;
+  Elf_Internal_Rela *           relend;
+
+  symtab_hdr = & elf_tdata (input_bfd)->symtab_hdr;
+  sym_hashes = elf_sym_hashes (input_bfd);
+  relend     = relocs + input_section->reloc_count;
+
+  for (rel = relocs; rel < relend; rel ++)
+    {
+      reloc_howto_type *           howto;
+      unsigned long                r_symndx;
+      Elf_Internal_Sym *           sym;
+      asection *                   sec;
+      struct elf_link_hash_entry * h;
+      bfd_vma                      relocation;
+      bfd_reloc_status_type        r;
+      const char *                 name = NULL;
+      int                          r_type;
+
+      r_type = ELF32_R_TYPE (rel->r_info);
+      r_symndx = ELF32_R_SYM (rel->r_info);
+
+      if (info->relocateable)
+	{
+	  /* This is a relocateable link.  We don't have to change
+             anything, unless the reloc is against a section symbol,
+             in which case we have to adjust according to where the
+             section symbol winds up in the output section.  */
+	  if (r_symndx < symtab_hdr->sh_info)
+	    {
+	      sym = local_syms + r_symndx;
+
+	      if (ELF_ST_TYPE (sym->st_info) == STT_SECTION)
+		{
+		  sec = local_sections [r_symndx];
+		  rel->r_addend += sec->output_offset + sym->st_value;
+		}
+	    }
+
+	  continue;
+	}
+
+      /* This is a final link.  */
+      howto  = elf_avr_howto_table + ELF32_R_TYPE (rel->r_info);
+      h      = NULL;
+      sym    = NULL;
+      sec    = NULL;
+
+      if (r_symndx < symtab_hdr->sh_info)
+	{
+	  sym = local_syms + r_symndx;
+	  sec = local_sections [r_symndx];
+	  relocation = (sec->output_section->vma
+			+ sec->output_offset
+			+ sym->st_value);
+
+	  name = bfd_elf_string_from_elf_section
+	    (input_bfd, symtab_hdr->sh_link, sym->st_name);
+	  name = (name == NULL) ? bfd_section_name (input_bfd, sec) : name;
+	}
+      else
+	{
+	  h = sym_hashes [r_symndx - symtab_hdr->sh_info];
+
+	  while (h->root.type == bfd_link_hash_indirect
+		 || h->root.type == bfd_link_hash_warning)
+	    h = (struct elf_link_hash_entry *) h->root.u.i.link;
+
+	  name = h->root.root.string;
+
+	  if (h->root.type == bfd_link_hash_defined
+	      || h->root.type == bfd_link_hash_defweak)
+	    {
+	      sec = h->root.u.def.section;
+	      relocation = (h->root.u.def.value
+			    + sec->output_section->vma
+			    + sec->output_offset);
+	    }
+	  else if (h->root.type == bfd_link_hash_undefweak)
+	    {
+	      relocation = 0;
+	    }
+	  else
+	    {
+	      if (! ((*info->callbacks->undefined_symbol)
+		     (info, h->root.root.string, input_bfd,
+		      input_section, rel->r_offset, true)))
+		return false;
+	      relocation = 0;
+	    }
+	}
+
+      r = avr_final_link_relocate (howto, input_bfd, input_section,
+				   contents, rel, relocation);
+
+      if (r != bfd_reloc_ok)
+	{
+	  const char * msg = (const char *) NULL;
+
+	  switch (r)
+	    {
+	    case bfd_reloc_overflow:
+	      r = info->callbacks->reloc_overflow
+		(info, name, howto->name, (bfd_vma) 0,
+		 input_bfd, input_section, rel->r_offset);
+	      break;
+
+	    case bfd_reloc_undefined:
+	      r = info->callbacks->undefined_symbol
+		(info, name, input_bfd, input_section, rel->r_offset, true);
+	      break;
+
+	    case bfd_reloc_outofrange:
+	      msg = _("internal error: out of range error");
+	      break;
+
+	    case bfd_reloc_notsupported:
+	      msg = _("internal error: unsupported relocation error");
+	      break;
+
+	    case bfd_reloc_dangerous:
+	      msg = _("internal error: dangerous relocation");
+	      break;
+
+	    default:
+	      msg = _("internal error: unknown error");
+	      break;
+	    }
+
+	  if (msg)
+	    r = info->callbacks->warning
+	      (info, msg, name, input_bfd, input_section, rel->r_offset);
+
+	  if (! r)
+	    return false;
+	}
+    }
+
+  return true;
+}
+
+/* The final processing done just before writing out a AVR ELF object
+   file.  This gets the AVR architecture right based on the machine
+   number.  */
+
+static void
+bfd_elf_avr_final_write_processing (abfd, linker)
+     bfd *abfd;
+     boolean linker ATTRIBUTE_UNUSED;
+{
+  unsigned long val;
+
+  switch (bfd_get_mach (abfd))
+    {
+    default:
+    case bfd_mach_avr2:
+      val = E_AVR_MACH_AVR2;
+      break;
+
+    case bfd_mach_avr1:
+      val = E_AVR_MACH_AVR1;
+      break;
+
+    case bfd_mach_avr3:
+      val = E_AVR_MACH_AVR3;
+      break;
+
+    case bfd_mach_avr4:
+      val = E_AVR_MACH_AVR4;
+      break;
+
+    }
+
+  elf_elfheader (abfd)->e_machine = EM_AVR;
+  elf_elfheader (abfd)->e_flags &= ~ EF_AVR_MACH;
+  elf_elfheader (abfd)->e_flags |= val;
+}
+
+/* Set the right machine number.  */
+
+static boolean
+elf32_avr_object_p (abfd)
+     bfd *abfd;
+{
+  int e_set = bfd_mach_avr2;
+  if (elf_elfheader (abfd)->e_machine == EM_AVR)
+    {
+      int e_mach = elf_elfheader (abfd)->e_flags & EF_AVR_MACH;
+      switch (e_mach)
+	{
+	default:
+	case E_AVR_MACH_AVR2:
+	  e_set = bfd_mach_avr2;
+	  break;
+
+	case E_AVR_MACH_AVR1:
+	  e_set = bfd_mach_avr1;
+	  break;
+
+	case E_AVR_MACH_AVR3:
+	  e_set = bfd_mach_avr3;
+	  break;
+
+	case E_AVR_MACH_AVR4:
+	  e_set = bfd_mach_avr4;
+	  break;
+	}
+    }
+  return bfd_default_set_arch_mach (abfd, bfd_arch_avr,
+				    e_set);
+}
+
+
+#define ELF_ARCH		bfd_arch_avr
+#define ELF_MACHINE_CODE	EM_AVR
+#define ELF_MAXPAGESIZE		1
+
+#define TARGET_LITTLE_SYM       bfd_elf32_avr_vec
+#define TARGET_LITTLE_NAME	"elf32-avr"
+
+#define elf_info_to_howto	             avr_info_to_howto_rela
+#define elf_info_to_howto_rel	             NULL
+#define elf_backend_relocate_section         elf32_avr_relocate_section
+#define elf_backend_gc_mark_hook             elf32_avr_gc_mark_hook
+#define elf_backend_gc_sweep_hook            elf32_avr_gc_sweep_hook
+#define elf_backend_check_relocs             elf32_avr_check_relocs
+#define elf_backend_can_gc_sections          1
+#define elf_backend_final_write_processing \
+					bfd_elf_avr_final_write_processing
+#define elf_backend_object_p		elf32_avr_object_p
+
+
+#include "elf32-target.h"