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#include <ctype.h>
#include <stdarg.h>
#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "spec.h"
#include "util.h"
struct Segment *g_segments;
int g_segmentsCount;
static void write_includes(const struct Segment *seg, FILE *fout, const char *segments_dir, const char *section)
{
// Note sections contain a suffix wildcard as compilers other than IDO such as GCC may emit sections titled
// e.g. .rodata.cstN, .rodata.strN.M, .text.FUNCNAME depending on their settings.
fprintf(fout, " %s/%s.plf (%s*)\n", segments_dir, seg->name, section);
}
static void write_ld_script(FILE *fout, uint32_t entrypoint_addr, const char *makerom_dir, const char *segments_dir)
{
int i;
fputs("OUTPUT_ARCH (mips)\n"
"\n"
"SECTIONS\n"
"{\n",
fout);
// Here we write the makerom segment in multiple parts, excluding it from the spec. Before, we would set a fake
// base address of (0x80000400 - 0x1000) so that entry.o, the only case that matters, would end up at the correct
// address. However, this is incompatible with converting the .elf to the ROM image via objcopy due to a bug in how
// binutils computes LMAs from elf sections. Using 0x7FFFF400, the LMA is somehow computed as equal to the VMA:
// Sections:
// Idx Name Size VMA LMA File off Algn
// 0 ..makerom 00001060 7ffff400 00000000 00009400 2**4 CONTENTS, ALLOC, LOAD, RELOC, CODE
// 1 ..makerom.bss 00000000 80000460 80000460 0000a460 2**4 ALLOC
// 2 ..boot 00011f10 80000460 80000460 0000a460 2**5 CONTENTS, ALLOC, LOAD, RELOC, CODE
// 3 ..boot.bss 00004a30 80012370 80012370 0001c370 2**4 ALLOC
// 4 ..dmadata 000060c0 80016da0 00012f70 0001cda0 2**4 CONTENTS, ALLOC, LOAD, RELOC, DATA
// 5 ..dmadata.bss 00000000 8001ce60 8001ce60 0359edf0 2**0 CONTENTS
// 6 ..Audiobank 0002bdc0 00000000 00019030 00023000 2**4 CONTENTS, ALLOC, LOAD, RELOC, CODE
//
// 0x7FFFF400 trips this bug likely due having a different 32-bit sign extension than the other addresses involved.
// Notably, llvm-objdump does not have the same problem with a base address of 0x7FFFF400:
// Sections:
// Idx Name Size VMA LMA Type
// 0 00000000 00000000 00000000
// 1 ..makerom 00001060 7ffff400 00000000 TEXT
// 2 .rel..makerom 00000040 00000000 00000000
// 3 ..makerom.bss 00000000 80000460 00001060 BSS
// 4 ..boot 00011f10 80000460 00001060 TEXT
// 5 .rel..boot 00005f60 00000000 00000000
// 6 ..boot.bss 00004a30 80012370 00012f70 BSS
// 7 ..dmadata 000060c0 80016da0 00012f70 DATA
//
// To simplify things, we simply fix the contents of makerom as they should not change anyway, and assign the
// address only when it matters. The ROM symbols for makerom must encompass these sections only as dmadata would
// not match otherwise.
fprintf(fout,
" /* makerom */" "\n"
"" "\n"
" ..makerom.hdr 0 : AT(0)" "\n"
" {" "\n"
" %s/rom_header.o(.text*)" "\n"
" %s/rom_header.o(.data*)" "\n"
" %s/rom_header.o(.rodata*)" "\n"
" }" "\n"
" ..makerom.ipl 0 : AT(SIZEOF(..makerom.hdr))" "\n"
" {" "\n"
" %s/ipl3.o(.text*)" "\n"
" %s/ipl3.o(.data*)" "\n"
" %s/ipl3.o(.rodata*)" "\n"
" }" "\n"
" ..makerom.ent 0x%08X : AT(SIZEOF(..makerom.hdr) + SIZEOF(..makerom.ipl))" "\n"
" {" "\n"
" %s/entry.o(.text*)" "\n"
" %s/entry.o(.data*)" "\n"
" %s/entry.o(.rodata*)" "\n"
" }" "\n"
" _makeromSegmentRomStart = LOADADDR(..makerom.hdr);" "\n"
" _makeromSegmentRomEnd = LOADADDR(..makerom.ent) + SIZEOF(..makerom.ent);" "\n"
" _makeromSegmentRomSize = SIZEOF(..makerom.hdr) + SIZEOF(..makerom.ipl) + SIZEOF(..makerom.ent);" "\n"
"" "\n",
makerom_dir, makerom_dir, makerom_dir,
makerom_dir, makerom_dir, makerom_dir,
entrypoint_addr,
makerom_dir, makerom_dir, makerom_dir
);
const char *last_end = "makerom";
uint32_t last_romalign = 0;
for (i = 0; i < g_segmentsCount; i++) {
const struct Segment *seg = &g_segments[i];
fprintf(fout, " /* %s */\n\n", seg->name);
// Begin initialized data (.text, .data, .rodata)
fprintf(fout, " ..%s ", seg->name);
if (seg->fields & (1 << STMT_after))
// Continue after the requested segment, aligning to the required alignment for the new segment.
fprintf(fout, "ALIGN(_%sSegmentEnd, %i)", seg->after, seg->align);
else if (seg->fields & (1 << STMT_number))
// Start at a new segmented address.
fprintf(fout, "0x%02X000000", seg->number);
else if (seg->fields & (1 << STMT_address))
// Start at a new absolute address.
fprintf(fout, "0x%08X", seg->address);
else
// Continue after previous segment, aligning to the required alignment for the new segment.
fprintf(fout, "ALIGN(0x%X)", seg->align);
// AT(...) isn't necessary, but adds useful "load address" lines to the map file.
// Also force an alignment of at least 0x10 at the start of any segment. This is especially important for
// overlays as the final link step must not introduce alignment padding between the SegmentTextStart symbol
// and the section contents as this would cause all generated relocations done prior to be wrong.
uint32_t next_romalign = (seg->fields & (1 << STMT_romalign)) ? seg->romalign : 0x10;
fprintf(fout, " : AT(ALIGN(_%sSegmentRomEnd, %u))\n", last_end,
(last_romalign > next_romalign) ? last_romalign : next_romalign);
last_romalign = next_romalign;
fprintf(fout, " {\n"
" . = ALIGN(0x10);\n"
" _%sSegmentStart = .;\n"
"\n",
seg->name);
// Write .text
fprintf(fout, " _%sSegmentTextStart = .;\n", seg->name);
write_includes(seg, fout, segments_dir, ".text");
fprintf(fout, " . = ALIGN(0x10);\n"
" _%sSegmentTextEnd = .;\n"
" _%sSegmentTextSize = ABSOLUTE( _%sSegmentTextEnd - _%sSegmentTextStart );\n"
"\n", seg->name, seg->name, seg->name, seg->name);
// Write .data
fprintf(fout, " _%sSegmentDataStart = .;\n", seg->name);
write_includes(seg, fout, segments_dir, ".data");
fprintf(fout, " . = ALIGN(0x10);\n"
" _%sSegmentDataEnd = .;\n"
" _%sSegmentDataSize = ABSOLUTE( _%sSegmentDataEnd - _%sSegmentDataStart );\n"
"\n", seg->name, seg->name, seg->name, seg->name);
// Write .rodata
fprintf(fout, " _%sSegmentRoDataStart = .;\n", seg->name);
write_includes(seg, fout, segments_dir, ".rodata");
fprintf(fout, " . = ALIGN(0x10);\n"
" _%sSegmentRoDataEnd = .;\n"
" _%sSegmentRoDataSize = ABSOLUTE( _%sSegmentRoDataEnd - _%sSegmentRoDataStart );\n"
"\n", seg->name, seg->name, seg->name, seg->name);
// Write an address increment if requested
if (seg->fields & (1 << STMT_increment))
fprintf(fout, " . += 0x%08X;\n", seg->increment);
if (seg->flags & FLAG_OVL) {
// Write .ovl if the segment is an overlay.
fprintf(fout, " _%sSegmentOvlStart = .;\n"
" %s/%s.reloc.o (.ovl)\n"
" _%sSegmentOvlEnd = .;\n"
" _%sSegmentOvlSize = ABSOLUTE( _%sSegmentOvlEnd - _%sSegmentOvlStart );\n"
"\n", seg->name, segments_dir, seg->name, seg->name, seg->name, seg->name, seg->name);
}
// End initialized data.
fprintf(fout, " }\n"
" _%sSegmentRomStart = LOADADDR(..%s);\n"
" _%sSegmentRomEnd = LOADADDR(..%s) + SIZEOF(..%s);\n"
" _%sSegmentRomSize = SIZEOF(..%s);\n"
"\n",
seg->name, seg->name,
seg->name, seg->name, seg->name,
seg->name, seg->name);
// Begin uninitialized data (.bss, COMMON, .scommon)
// Note we must enforce a minimum alignment of at least 8 for
// bss sections due to how bss is cleared in steps of 8 in
// entry.s, and more widely it's more efficient.
fprintf(fout, " ..%s.bss (NOLOAD) : AT(_%sSegmentRomEnd)\n"
" {\n"
" . = ALIGN(8);\n"
" _%sSegmentBssStart = .;\n",
seg->name, seg->name, seg->name);
// Write sections
write_includes(seg, fout, segments_dir, ".scommon");
write_includes(seg, fout, segments_dir, "COMMON");
write_includes(seg, fout, segments_dir, ".bss");
// End uninitialized data
fprintf(fout, " . = ALIGN(8);\n"
" _%sSegmentBssEnd = .;\n"
" _%sSegmentBssSize = ABSOLUTE( _%sSegmentBssEnd - _%sSegmentBssStart );\n"
"\n"
" _%sSegmentEnd = .;\n"
" }\n"
"\n",
seg->name, seg->name, seg->name, seg->name, seg->name);
last_end = seg->name;
}
fprintf(fout, " _RomSize = ALIGN(_%sSegmentRomEnd, %u);\n\n", last_end, last_romalign);
// Debugging sections
fputs(
// mdebug sections
" .pdr : { *(.pdr) }" "\n"
" .mdebug : { *(.mdebug) }" "\n"
// Stabs debugging sections
" .stab 0 : { *(.stab) }" "\n"
" .stabstr 0 : { *(.stabstr) }" "\n"
" .stab.excl 0 : { *(.stab.excl) }" "\n"
" .stab.exclstr 0 : { *(.stab.exclstr) }" "\n"
" .stab.index 0 : { *(.stab.index) }" "\n"
" .stab.indexstr 0 : { *(.stab.indexstr) }" "\n"
" .comment 0 : { *(.comment) }" "\n"
" .gnu.build.attributes : { *(.gnu.build.attributes .gnu.build.attributes.*) }" "\n"
// DWARF debug sections
// Symbols in the DWARF debugging sections are relative to the beginning of the section so we begin them at 0.
// DWARF 1
" .debug 0 : { *(.debug) }" "\n"
" .line 0 : { *(.line) }" "\n"
// GNU DWARF 1 extensions
" .debug_srcinfo 0 : { *(.debug_srcinfo) }" "\n"
" .debug_sfnames 0 : { *(.debug_sfnames) }" "\n"
// DWARF 1.1 and DWARF 2
" .debug_aranges 0 : { *(.debug_aranges) }" "\n"
" .debug_pubnames 0 : { *(.debug_pubnames) }" "\n"
// DWARF 2
" .debug_info 0 : { *(.debug_info .gnu.linkonce.wi.*) }" "\n"
" .debug_abbrev 0 : { *(.debug_abbrev) }" "\n"
" .debug_line 0 : { *(.debug_line .debug_line.* .debug_line_end ) }" "\n"
" .debug_frame 0 : { *(.debug_frame) }" "\n"
" .debug_str 0 : { *(.debug_str) }" "\n"
" .debug_loc 0 : { *(.debug_loc) }" "\n"
" .debug_macinfo 0 : { *(.debug_macinfo) }" "\n"
// SGI/MIPS DWARF 2 extensions
" .debug_weaknames 0 : { *(.debug_weaknames) }" "\n"
" .debug_funcnames 0 : { *(.debug_funcnames) }" "\n"
" .debug_typenames 0 : { *(.debug_typenames) }" "\n"
" .debug_varnames 0 : { *(.debug_varnames) }" "\n"
// DWARF 3
" .debug_pubtypes 0 : { *(.debug_pubtypes) }" "\n"
" .debug_ranges 0 : { *(.debug_ranges) }" "\n"
// DWARF 5
" .debug_addr 0 : { *(.debug_addr) }" "\n"
" .debug_line_str 0 : { *(.debug_line_str) }" "\n"
" .debug_loclists 0 : { *(.debug_loclists) }" "\n"
" .debug_macro 0 : { *(.debug_macro) }" "\n"
" .debug_names 0 : { *(.debug_names) }" "\n"
" .debug_rnglists 0 : { *(.debug_rnglists) }" "\n"
" .debug_str_offsets 0 : { *(.debug_str_offsets) }" "\n"
" .debug_sup 0 : { *(.debug_sup) }" "\n"
// gnu attributes
" .gnu.attributes 0 : { KEEP (*(.gnu.attributes)) }" "\n"
// Sections generated by GCC to inform GDB about the ABI
" .mdebug.abi32 0 : { KEEP (*(.mdebug.abi32)) }" "\n"
" .mdebug.abiN32 0 : { KEEP (*(.mdebug.abiN32)) }" "\n"
" .mdebug.abi64 0 : { KEEP (*(.mdebug.abi64)) }" "\n"
" .mdebug.abiO64 0 : { KEEP (*(.mdebug.abiO64)) }" "\n"
" .mdebug.eabi32 0 : { KEEP (*(.mdebug.eabi32)) }" "\n"
" .mdebug.eabi64 0 : { KEEP (*(.mdebug.eabi64)) }" "\n"
" .gcc_compiled_long32 0 : { KEEP (*(.gcc_compiled_long32)) }" "\n"
" .gcc_compiled_long64 0 : { KEEP (*(.gcc_compiled_long64)) }" "\n\n", fout);
// Discard all other sections not mentioned above
fputs(" /DISCARD/ :" "\n"
" {" "\n"
" *(*);" "\n"
" }" "\n"
"}\n", fout);
}
static void usage(const char *execname)
{
fprintf(stderr, "Nintendo 64 linker script generation tool v0.04\n"
"usage: %s SPEC_FILE LD_SCRIPT SEGMENTS_DIR MAKEROM_DIR\n"
"SPEC_FILE file describing the organization of object files into segments\n"
"LD_SCRIPT filename of output linker script\n"
"MAKEROM_DIR dir name containing makerom build objects\n"
"SEGMENTS_DIR dir name containing partially linked segments\n",
execname);
}
int main(int argc, char **argv)
{
FILE *ldout;
void *spec;
size_t size;
if (argc != 5) {
usage(argv[0]);
return EXIT_FAILURE;
}
spec = util_read_whole_file(argv[1], &size);
parse_rom_spec(spec, &g_segments, &g_segmentsCount);
ldout = fopen(argv[2], "w");
if (ldout == NULL)
util_fatal_error("failed to open file '%s' for writing", argv[2]);
uint32_t entrypoint_addr = 0x80000400;
write_ld_script(ldout, entrypoint_addr, argv[3], argv[4]);
fclose(ldout);
free_rom_spec(g_segments, g_segmentsCount);
free(spec);
return EXIT_SUCCESS;
}
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