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/* -*- sh -*- */
/*
* Linker script for i386 images
*
*/
OUTPUT_FORMAT ( "elf32-i386", "elf32-i386", "elf32-i386" )
OUTPUT_ARCH ( i386 )
ENTRY ( _entry )
SECTIONS {
/* All sections in the resulting file have consecutive load
* addresses, but may have individual link addresses depending on
* the memory model being used.
*
* We guarantee alignment of virtual addresses to any alignment
* specified by the constituent object files (e.g. via
* __attribute__((aligned(x)))). Load addresses are guaranteed
* only up to _max_align. Provided that all loader and relocation
* code honours _max_align, this means that physical addresses are
* also guaranteed up to _max_align.
*
* Note that when using -DKEEP_IT_REAL, the UNDI segments are only
* guaranteed to be loaded on a paragraph boundary (i.e. 16-byte
* alignment). Using _max_align>16 will therefore not guarantee
* >16-byte alignment of physical addresses when -DKEEP_IT_REAL is
* used (though virtual addresses will still be fully aligned).
*
*/
/*
* Weak symbols that need zero values if not otherwise defined
*/
. = 0;
.weak : AT ( 0 ) {
*(.weak)
}
_assert = ASSERT ( ( . == 0 ), ".weak is non-zero length" );
/*
* The prefix
*/
_prefix_link_addr = 0;
. = _prefix_link_addr;
_prefix = .;
.prefix : AT ( _prefix_load_offset + __prefix ) {
__prefix = .;
_entry = .;
*(.prefix)
*(.prefix.*)
_eprefix_progbits = .;
}
_eprefix = .;
/*
* The 16-bit sections, if present
*/
_text16_link_addr = 0;
. = _text16_link_addr;
_text16 = .;
/* We need to allow code at the NULL address in .text16 */
.text16 : AT ( _text16_load_offset + __text16 ) {
__text16 = .;
*(.text16.null)
. += 1; /* Prevent NULL being valid */
*(.text16)
*(.text16.*)
_etext16_progbits = .;
} = 0x9090
_etext16 = .;
_data16_link_addr = 0;
. = _data16_link_addr;
_data16 = .;
. += 1; /* Prevent NULL being valid */
.rodata16 : AT ( _data16_load_offset + __rodata16 ) {
__rodata16 = .;
*(.rodata16)
*(.rodata16.*)
}
.data16 : AT ( _data16_load_offset + __data16 ) {
__data16 = .;
*(.data16)
*(.data16.*)
_edata16_progbits = .;
}
.bss16 : AT ( _data16_load_offset + __bss16 ) {
__bss16 = .;
_bss16 = .;
*(.bss16)
*(.bss16.*)
_ebss16 = .;
}
.stack16 : AT ( _data16_load_offset + __stack16 ) {
__stack16 = .;
*(.stack16)
*(.stack16.*)
}
_edata16 = .;
/*
* The 32-bit sections
*/
_textdata_link_addr = 0;
. = _textdata_link_addr;
_textdata = .;
_text = .;
. += 1; /* Prevent NULL being valid */
.text : AT ( _textdata_load_offset + __text ) {
__text = .;
*(.text.null_trap)
*(.text)
*(.text.*)
} = 0x9090
_etext = .;
_data = .;
.rodata : AT ( _textdata_load_offset + __rodata ) {
__rodata = .;
*(.rodata)
*(.rodata.*)
}
.data : AT ( _textdata_load_offset + __data ) {
__data = .;
*(.data)
*(.data.*)
*(SORT(.tbl.*)) /* Various tables. See include/tables.h */
_etextdata_progbits = .;
}
.bss : AT ( _textdata_load_offset + __bss ) {
__bss = .;
_bss = .;
*(.bss)
*(.bss.*)
*(COMMON)
_ebss = .;
}
.stack : AT ( _textdata_load_offset + __stack ) {
__stack = .;
*(.stack)
*(.stack.*)
}
_edata = .;
_etextdata = .;
_end = .;
/*
* Compressor information block
*/
_zinfo_link_addr = 0;
. = _zinfo_link_addr;
_zinfo = .;
.zinfo : AT ( _zinfo_load_offset + __zinfo ) {
__zinfo = .;
_entry = .;
*(.zinfo)
*(.zinfo.*)
_ezinfo_progbits = .;
}
_ezinfo = .;
/*
* Dispose of the comment and note sections to make the link map
* easier to read
*/
/DISCARD/ : {
*(.comment)
*(.note)
}
/*
* Load address calculations. The slightly obscure nature of the
* calculations is because ALIGN(x) can only operate on the
* location counter.
*/
_max_align = 16;
_load_addr = 0;
. = _load_addr;
. -= _prefix_link_addr;
_prefix_load_offset = ALIGN ( _max_align );
_prefix_load_addr = _prefix_link_addr + _prefix_load_offset;
_prefix_size = _eprefix - _prefix;
_prefix_progbits_size = _eprefix_progbits - _prefix;
. = _prefix_load_addr + _prefix_progbits_size;
. -= _text16_link_addr;
_text16_load_offset = ALIGN ( _max_align );
_text16_load_addr = _text16_link_addr + _text16_load_offset;
_text16_size = _etext16 - _text16;
_text16_progbits_size = _etext16_progbits - _text16;
. = _text16_load_addr + _text16_progbits_size;
. -= _data16_link_addr;
_data16_load_offset = ALIGN ( _max_align );
_data16_load_addr = _data16_link_addr + _data16_load_offset;
_data16_size = _edata16 - _data16;
_data16_progbits_size = _edata16_progbits - _data16;
. = _data16_load_addr + _data16_progbits_size;
. -= _textdata_link_addr;
_textdata_load_offset = ALIGN ( _max_align );
_textdata_load_addr = _textdata_link_addr + _textdata_load_offset;
_textdata_size = _etextdata - _textdata;
_textdata_progbits_size = _etextdata_progbits - _textdata;
. = _textdata_load_addr + _textdata_progbits_size;
_load_size = . - _load_addr;
. -= _zinfo_link_addr;
_zinfo_load_offset = ALIGN ( _max_align );
_zinfo_load_addr = _zinfo_link_addr + _zinfo_load_offset;
_zinfo_size = _ezinfo - _zinfo;
_zinfo_progbits_size = _ezinfo_progbits - _zinfo;
. = _zinfo_load_addr + _zinfo_progbits_size;
_payload_offset = _text16_load_offset;
/*
* Alignment checks. ALIGN() can only operate on the location
* counter, so we set the location counter to each value we want
* to check.
*/
. = _prefix_load_addr - _prefix_link_addr;
_assert = ASSERT ( ( . == ALIGN ( _max_align ) ),
"_prefix is badly aligned" );
. = _text16_load_addr - _text16_link_addr;
_assert = ASSERT ( ( . == ALIGN ( _max_align ) ),
"_text16 is badly aligned" );
. = _data16_load_addr - _data16_link_addr;
_assert = ASSERT ( ( . == ALIGN ( _max_align ) ),
"_data16 is badly aligned" );
. = _textdata_load_addr - _textdata_link_addr;
_assert = ASSERT ( ( . == ALIGN ( _max_align ) ),
"_text is badly aligned" );
/*
* Values calculated to save code from doing it
*/
_prefix_size_pgh = ( ( _prefix_size + 15 ) / 16 );
_prefix_size_sect = ( ( _prefix_size + 511 ) / 512 );
_text16_size_pgh = ( ( _text16_size + 15 ) / 16 );
_data16_size_pgh = ( ( _data16_size + 15 ) / 16 );
/*
* Load sizes in paragraphs and sectors. Note that wherever the
* _load_size variables are used, there must be a corresponding
* .zinfo.fixup section.
*/
_load_size_pgh = ( ( _load_size + 15 ) / 16 );
_load_size_sect = ( ( _load_size + 511 ) / 512 );
}
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