1 /* load.c --- loading object files into the RX simulator. 2 3 Copyright (C) 2005-2014 Free Software Foundation, Inc. 4 Contributed by Red Hat, Inc. 5 6 This file is part of the GNU simulators. 7 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 3 of the License, or 11 (at your option) any later version. 12 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. 17 18 You should have received a copy of the GNU General Public License 19 along with this program. If not, see <http://www.gnu.org/licenses/>. */ 20 21 22 #include "config.h" 23 #include <stdlib.h> 24 #include <stdio.h> 25 #include <string.h> 26 27 #include "bfd.h" 28 #include "libbfd.h" 29 #include "cpu.h" 30 #include "mem.h" 31 #include "load.h" 32 #include "elf/internal.h" 33 #include "elf/common.h" 34 35 /* Helper function for invoking a GDB-specified printf. */ 36 static void 37 xprintf (host_callback *callback, const char *fmt, ...) 38 { 39 va_list ap; 40 41 va_start (ap, fmt); 42 43 (*callback->vprintf_filtered) (callback, fmt, ap); 44 45 va_end (ap); 46 } 47 48 /* Given a file offset, look up the section name. */ 49 static const char * 50 find_section_name_by_offset (bfd *abfd, file_ptr filepos) 51 { 52 asection *s; 53 54 for (s = abfd->sections; s; s = s->next) 55 if (s->filepos == filepos) 56 return bfd_get_section_name (abfd, s); 57 58 return "(unknown)"; 59 } 60 61 /* A note about endianness and swapping... 62 63 The RX chip is CISC-like in that the opcodes are variable length 64 and are read as a stream of bytes. However, the chip itself shares 65 the code prefetch block with the data fetch block, so when it's 66 configured for big endian mode, the memory fetched for opcodes is 67 word-swapped. To compensate for this, the ELF file has the code 68 sections pre-swapped. Our BFD knows this, and for the convenience 69 of all the other tools, hides this swapping at a very low level. 70 I.e. it swaps words on the way out and on the way back in. 71 72 Fortunately the iovector routines are unaffected by this, so we 73 can use them to read in the segments directly, without having 74 to worry about byte swapping anything. 75 76 However, our opcode decoder and disassemblers need to swap the data 77 after reading it from the chip memory, just like the chip does. 78 All in all, the code words are swapped four times between the 79 assembler and our decoder. 80 81 If the chip is running in little-endian mode, no swapping is done 82 anywhere. Note also that the *operands* within opcodes are always 83 encoded in little-endian format. */ 84 85 void 86 rx_load (bfd *prog, host_callback *callback) 87 { 88 unsigned long highest_addr_loaded = 0; 89 Elf_Internal_Phdr * phdrs; 90 long sizeof_phdrs; 91 int num_headers; 92 int i; 93 94 rx_big_endian = bfd_big_endian (prog); 95 96 /* Note we load by ELF program header not by BFD sections. 97 This is because BFD sections get their information from 98 the ELF section structure, which only includes a VMA value 99 and not an LMA value. */ 100 sizeof_phdrs = bfd_get_elf_phdr_upper_bound (prog); 101 if (sizeof_phdrs == 0) 102 { 103 fprintf (stderr, "Failed to get size of program headers\n"); 104 return; 105 } 106 phdrs = malloc (sizeof_phdrs); 107 if (phdrs == NULL) 108 { 109 fprintf (stderr, "Failed allocate memory to hold program headers\n"); 110 return; 111 } 112 num_headers = bfd_get_elf_phdrs (prog, phdrs); 113 if (num_headers < 1) 114 { 115 fprintf (stderr, "Failed to read program headers\n"); 116 return; 117 } 118 119 for (i = 0; i < num_headers; i++) 120 { 121 Elf_Internal_Phdr * p = phdrs + i; 122 char *buf; 123 bfd_vma size; 124 bfd_vma base; 125 file_ptr offset; 126 127 size = p->p_filesz; 128 if (size <= 0) 129 continue; 130 131 base = p->p_paddr; 132 if (verbose > 1) 133 fprintf (stderr, "[load segment: lma=%08x vma=%08x size=%08x]\n", 134 (int) base, (int) p->p_vaddr, (int) size); 135 if (callback) 136 xprintf (callback, 137 "Loading section %s, size %#lx lma %08lx vma %08lx\n", 138 find_section_name_by_offset (prog, p->p_offset), 139 size, base, p->p_vaddr); 140 141 buf = malloc (size); 142 if (buf == NULL) 143 { 144 fprintf (stderr, "Failed to allocate buffer to hold program segment\n"); 145 continue; 146 } 147 148 offset = p->p_offset; 149 if (prog->iovec->bseek (prog, offset, SEEK_SET) != 0) 150 { 151 fprintf (stderr, "Failed to seek to offset %lx\n", (long) offset); 152 continue; 153 } 154 if (prog->iovec->bread (prog, buf, size) != size) 155 { 156 fprintf (stderr, "Failed to read %lx bytes\n", size); 157 continue; 158 } 159 160 mem_put_blk (base, buf, size); 161 free (buf); 162 if (highest_addr_loaded < base + size - 1 && size >= 4) 163 highest_addr_loaded = base + size - 1; 164 } 165 166 free (phdrs); 167 168 regs.r_pc = prog->start_address; 169 170 if (strcmp (bfd_get_target (prog), "srec") == 0 171 || regs.r_pc == 0) 172 { 173 regs.r_pc = mem_get_si (0xfffffffc); 174 heaptop = heapbottom = 0; 175 } 176 177 reset_decoder (); 178 179 if (verbose > 1) 180 fprintf (stderr, "[start pc=%08x %s]\n", 181 (unsigned int) regs.r_pc, 182 rx_big_endian ? "BE" : "LE"); 183 } 184