931 lines
21 KiB
ArmAsm
931 lines
21 KiB
ArmAsm
/*
|
|
* Copyright (C) 2006 Michael Brown <mbrown@fensystems.co.uk>.
|
|
*
|
|
* 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 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., 51 Franklin Street, Fifth Floor, Boston, MA
|
|
* 02110-1301, USA.
|
|
*
|
|
*/
|
|
|
|
FILE_LICENCE ( GPL2_OR_LATER )
|
|
|
|
.arch i386
|
|
|
|
/* Image compression enabled */
|
|
#define COMPRESS 1
|
|
|
|
/* Protected mode flag */
|
|
#define CR0_PE 1
|
|
|
|
/* Allow for DBG()-style messages within libprefix */
|
|
#ifdef NDEBUG
|
|
.macro progress message
|
|
.endm
|
|
#else
|
|
.macro progress message
|
|
pushfl
|
|
pushw %ds
|
|
pushw %si
|
|
pushw %di
|
|
pushw %cs
|
|
popw %ds
|
|
xorw %di, %di
|
|
movw $progress_\@, %si
|
|
call print_message
|
|
popw %di
|
|
popw %si
|
|
popw %ds
|
|
popfl
|
|
.section ".prefix.data", "aw", @progbits
|
|
progress_\@:
|
|
.asciz "\message"
|
|
.size progress_\@, . - progress_\@
|
|
.previous
|
|
.endm
|
|
#endif
|
|
|
|
/*****************************************************************************
|
|
* Utility function: print character (with LF -> LF,CR translation)
|
|
*
|
|
* Parameters:
|
|
* %al : character to print
|
|
* %ds:di : output buffer (or %di=0 to print to console)
|
|
* Returns:
|
|
* %ds:di : next character in output buffer (if applicable)
|
|
*****************************************************************************
|
|
*/
|
|
.section ".prefix.lib", "awx", @progbits
|
|
.code16
|
|
.globl print_character
|
|
print_character:
|
|
/* Preserve registers */
|
|
pushw %ax
|
|
pushw %bx
|
|
pushw %bp
|
|
/* If %di is non-zero, write character to buffer and exit */
|
|
testw %di, %di
|
|
jz 1f
|
|
movb %al, %ds:(%di)
|
|
incw %di
|
|
jmp 3f
|
|
1: /* Print character */
|
|
movw $0x0007, %bx /* page 0, attribute 7 (normal) */
|
|
movb $0x0e, %ah /* write char, tty mode */
|
|
cmpb $0x0a, %al /* '\n'? */
|
|
jne 2f
|
|
int $0x10
|
|
movb $0x0d, %al
|
|
2: int $0x10
|
|
/* Restore registers and return */
|
|
3: popw %bp
|
|
popw %bx
|
|
popw %ax
|
|
ret
|
|
.size print_character, . - print_character
|
|
|
|
/*****************************************************************************
|
|
* Utility function: print a NUL-terminated string
|
|
*
|
|
* Parameters:
|
|
* %ds:si : string to print
|
|
* %ds:di : output buffer (or %di=0 to print to console)
|
|
* Returns:
|
|
* %ds:si : character after terminating NUL
|
|
* %ds:di : next character in output buffer (if applicable)
|
|
*****************************************************************************
|
|
*/
|
|
.section ".prefix.lib", "awx", @progbits
|
|
.code16
|
|
.globl print_message
|
|
print_message:
|
|
/* Preserve registers */
|
|
pushw %ax
|
|
/* Print string */
|
|
1: lodsb
|
|
testb %al, %al
|
|
je 2f
|
|
call print_character
|
|
jmp 1b
|
|
2: /* Restore registers and return */
|
|
popw %ax
|
|
ret
|
|
.size print_message, . - print_message
|
|
|
|
/*****************************************************************************
|
|
* Utility functions: print hex digit/byte/word/dword
|
|
*
|
|
* Parameters:
|
|
* %al (low nibble) : digit to print
|
|
* %al : byte to print
|
|
* %ax : word to print
|
|
* %eax : dword to print
|
|
* %ds:di : output buffer (or %di=0 to print to console)
|
|
* Returns:
|
|
* %ds:di : next character in output buffer (if applicable)
|
|
*****************************************************************************
|
|
*/
|
|
.section ".prefix.lib", "awx", @progbits
|
|
.code16
|
|
.globl print_hex_dword
|
|
print_hex_dword:
|
|
rorl $16, %eax
|
|
call print_hex_word
|
|
rorl $16, %eax
|
|
/* Fall through */
|
|
.size print_hex_dword, . - print_hex_dword
|
|
.globl print_hex_word
|
|
print_hex_word:
|
|
xchgb %al, %ah
|
|
call print_hex_byte
|
|
xchgb %al, %ah
|
|
/* Fall through */
|
|
.size print_hex_word, . - print_hex_word
|
|
.globl print_hex_byte
|
|
print_hex_byte:
|
|
rorb $4, %al
|
|
call print_hex_nibble
|
|
rorb $4, %al
|
|
/* Fall through */
|
|
.size print_hex_byte, . - print_hex_byte
|
|
.globl print_hex_nibble
|
|
print_hex_nibble:
|
|
/* Preserve registers */
|
|
pushw %ax
|
|
/* Print digit (technique by Norbert Juffa <norbert.juffa@amd.com> */
|
|
andb $0x0f, %al
|
|
cmpb $10, %al
|
|
sbbb $0x69, %al
|
|
das
|
|
call print_character
|
|
/* Restore registers and return */
|
|
popw %ax
|
|
ret
|
|
.size print_hex_nibble, . - print_hex_nibble
|
|
|
|
/*****************************************************************************
|
|
* Utility function: print PCI bus:dev.fn
|
|
*
|
|
* Parameters:
|
|
* %ax : PCI bus:dev.fn to print
|
|
* %ds:di : output buffer (or %di=0 to print to console)
|
|
* Returns:
|
|
* %ds:di : next character in output buffer (if applicable)
|
|
*****************************************************************************
|
|
*/
|
|
.section ".prefix.lib", "awx", @progbits
|
|
.code16
|
|
.globl print_pci_busdevfn
|
|
print_pci_busdevfn:
|
|
/* Preserve registers */
|
|
pushw %ax
|
|
/* Print bus */
|
|
xchgb %al, %ah
|
|
call print_hex_byte
|
|
/* Print ":" */
|
|
movb $( ':' ), %al
|
|
call print_character
|
|
/* Print device */
|
|
movb %ah, %al
|
|
shrb $3, %al
|
|
call print_hex_byte
|
|
/* Print "." */
|
|
movb $( '.' ), %al
|
|
call print_character
|
|
/* Print function */
|
|
movb %ah, %al
|
|
andb $0x07, %al
|
|
call print_hex_nibble
|
|
/* Restore registers and return */
|
|
popw %ax
|
|
ret
|
|
.size print_pci_busdevfn, . - print_pci_busdevfn
|
|
|
|
/*****************************************************************************
|
|
* Utility function: clear current line
|
|
*
|
|
* Parameters:
|
|
* %ds:di : output buffer (or %di=0 to print to console)
|
|
* Returns:
|
|
* %ds:di : next character in output buffer (if applicable)
|
|
*****************************************************************************
|
|
*/
|
|
.section ".prefix.lib", "awx", @progbits
|
|
.code16
|
|
.globl print_kill_line
|
|
print_kill_line:
|
|
/* Preserve registers */
|
|
pushw %ax
|
|
pushw %cx
|
|
/* Print CR */
|
|
movb $( '\r' ), %al
|
|
call print_character
|
|
/* Print 79 spaces */
|
|
movb $( ' ' ), %al
|
|
movw $79, %cx
|
|
1: call print_character
|
|
loop 1b
|
|
/* Print CR */
|
|
movb $( '\r' ), %al
|
|
call print_character
|
|
/* Restore registers and return */
|
|
popw %cx
|
|
popw %ax
|
|
ret
|
|
.size print_kill_line, . - print_kill_line
|
|
|
|
/****************************************************************************
|
|
* copy_bytes
|
|
*
|
|
* Copy bytes
|
|
*
|
|
* Parameters:
|
|
* %ds:esi : source address
|
|
* %es:edi : destination address
|
|
* %ecx : length
|
|
* Returns:
|
|
* %ds:esi : next source address
|
|
* %es:edi : next destination address
|
|
* Corrupts:
|
|
* None
|
|
****************************************************************************
|
|
*/
|
|
.section ".prefix.lib", "awx", @progbits
|
|
.code16
|
|
copy_bytes:
|
|
pushl %ecx
|
|
rep addr32 movsb
|
|
popl %ecx
|
|
ret
|
|
.size copy_bytes, . - copy_bytes
|
|
|
|
/****************************************************************************
|
|
* zero_bytes
|
|
*
|
|
* Zero bytes
|
|
*
|
|
* Parameters:
|
|
* %ds:esi : source address
|
|
* %es:edi : destination address
|
|
* %ecx : length
|
|
* Returns:
|
|
* %ds:esi : next source address
|
|
* %es:edi : next destination address
|
|
* Corrupts:
|
|
* None
|
|
****************************************************************************
|
|
*/
|
|
.section ".prefix.lib", "awx", @progbits
|
|
.code16
|
|
zero_bytes:
|
|
pushl %ecx
|
|
pushw %ax
|
|
xorw %ax, %ax
|
|
rep addr32 stosb
|
|
popw %ax
|
|
popl %ecx
|
|
ret
|
|
.size zero_bytes, . - zero_bytes
|
|
|
|
/****************************************************************************
|
|
* process_bytes
|
|
*
|
|
* Call memcpy()-like function
|
|
*
|
|
* Parameters:
|
|
* %esi : source physical address
|
|
* %edi : destination physical address
|
|
* %ecx : length
|
|
* %bx : memcpy()-like function to call, passing parameters:
|
|
* %ds:esi : source address
|
|
* %es:edi : destination address
|
|
* %ecx : length
|
|
* and returning:
|
|
* %ds:esi : next source address
|
|
* %es:edi : next destination address
|
|
* Returns:
|
|
* %esi : next source physical address
|
|
* %edi : next destination physical address
|
|
* Corrupts:
|
|
* None
|
|
****************************************************************************
|
|
*/
|
|
.section ".prefix.lib", "awx", @progbits
|
|
.code16
|
|
process_bytes:
|
|
|
|
#ifndef KEEP_IT_REAL
|
|
|
|
/* Preserve registers */
|
|
pushl %eax
|
|
pushl %ebp
|
|
|
|
/* Construct GDT on stack (since .prefix may not be writable) */
|
|
.equ PM_DS, 0x18 /* Flat data segment */
|
|
pushl $0x00cf9300
|
|
pushl $0x0000ffff
|
|
.equ PM_SS, 0x10 /* Stack segment based at %ss:0000 */
|
|
pushl $0x008f0930
|
|
pushw %ss
|
|
pushw $0xffff
|
|
.equ PM_CS, 0x08 /* Code segment based at %cs:0000 */
|
|
pushl $0x008f09b0
|
|
pushw %cs
|
|
pushw $0xffff
|
|
pushl $0 /* Base and length */
|
|
pushw %ss
|
|
pushw $0x1f
|
|
movzwl %sp, %ebp
|
|
shll $4, 0x02(%bp)
|
|
addl %ebp, 0x02(%bp)
|
|
shll $4, 0x0a(%bp)
|
|
shll $4, 0x12(%bp)
|
|
subw $8, %sp
|
|
sgdt -8(%bp)
|
|
|
|
/* Switch to protected mode */
|
|
pushw %gs
|
|
pushw %fs
|
|
pushw %es
|
|
pushw %ds
|
|
pushw %ss
|
|
pushw %cs
|
|
pushw $2f
|
|
cli
|
|
data32 lgdt (%bp)
|
|
movl %cr0, %eax
|
|
orb $CR0_PE, %al
|
|
movl %eax, %cr0
|
|
ljmp $PM_CS, $1f
|
|
1: movw $PM_SS, %ax
|
|
movw %ax, %ss
|
|
movw $PM_DS, %ax
|
|
movw %ax, %ds
|
|
movw %ax, %es
|
|
movw %ax, %fs
|
|
movw %ax, %gs
|
|
|
|
/* Call memcpy()-like function */
|
|
call *%bx
|
|
|
|
/* Return to (flat) real mode */
|
|
movl %cr0, %eax
|
|
andb $0!CR0_PE, %al
|
|
movl %eax, %cr0
|
|
lret
|
|
2: /* lret will ljmp to here */
|
|
popw %ss
|
|
popw %ds
|
|
popw %es
|
|
popw %fs
|
|
popw %gs
|
|
|
|
/* Restore GDT */
|
|
data32 lgdt -8(%bp)
|
|
addw $( 8 /* saved GDT */ + ( PM_DS + 8 ) /* GDT on stack */ ), %sp
|
|
|
|
/* Restore registers and return */
|
|
popl %ebp
|
|
popl %eax
|
|
ret
|
|
|
|
#else /* KEEP_IT_REAL */
|
|
|
|
/* Preserve registers */
|
|
pushl %eax
|
|
pushw %ds
|
|
pushw %es
|
|
|
|
/* Convert %esi and %edi to %ds:esi and %es:edi */
|
|
shrl $4, %esi
|
|
movw %si, %ds
|
|
xorw %si, %si
|
|
shll $4, %esi
|
|
shrl $4, %edi
|
|
movw %di, %es
|
|
xorw %di, %di
|
|
shll $4, %edi
|
|
|
|
/* Call memcpy()-like function */
|
|
call *%bx
|
|
|
|
/* Convert %ds:esi and %es:edi back to physical addresses */
|
|
xorl %eax, %eax
|
|
movw %ds, %cx
|
|
shll $4, %eax
|
|
addl %eax, %esi
|
|
xorl %eax, %eax
|
|
movw %es, %cx
|
|
shll $4, %eax
|
|
addl %eax, %edi
|
|
|
|
/* Restore registers and return */
|
|
popw %es
|
|
popw %ds
|
|
popl %eax
|
|
ret
|
|
|
|
#endif /* KEEP_IT_REAL */
|
|
|
|
.size process_bytes, . - process_bytes
|
|
|
|
/****************************************************************************
|
|
* install_block
|
|
*
|
|
* Install block to specified address
|
|
*
|
|
* Parameters:
|
|
* %esi : source physical address (must be a multiple of 16)
|
|
* %edi : destination physical address (must be a multiple of 16)
|
|
* %ecx : length of (decompressed) data
|
|
* %edx : total length of block (including any uninitialised data portion)
|
|
* Returns:
|
|
* %esi : next source physical address (will be a multiple of 16)
|
|
* %edi : next destination physical address (will be a multiple of 16)
|
|
* Corrupts:
|
|
* none
|
|
****************************************************************************
|
|
*/
|
|
.section ".prefix.lib", "awx", @progbits
|
|
.code16
|
|
install_block:
|
|
/* Preserve registers */
|
|
pushl %ecx
|
|
pushw %bx
|
|
|
|
/* Decompress (or copy) source to destination */
|
|
#if COMPRESS
|
|
movw $decompress16, %bx
|
|
#else
|
|
movw $copy_bytes, %bx
|
|
#endif
|
|
call process_bytes
|
|
|
|
/* Zero .bss portion */
|
|
negl %ecx
|
|
addl %edx, %ecx
|
|
movw $zero_bytes, %bx
|
|
call process_bytes
|
|
|
|
/* Round up %esi and %edi to start of next blocks */
|
|
addl $0xf, %esi
|
|
andl $~0xf, %esi
|
|
addl $0xf, %edi
|
|
andl $~0xf, %edi
|
|
|
|
/* Restore registers and return */
|
|
popw %bx
|
|
popl %ecx
|
|
ret
|
|
.size install_block, . - install_block
|
|
|
|
/****************************************************************************
|
|
* alloc_basemem
|
|
*
|
|
* Allocate space for .text16 and .data16 from top of base memory.
|
|
* Memory is allocated using the BIOS free base memory counter at
|
|
* 0x40:13.
|
|
*
|
|
* Parameters:
|
|
* none
|
|
* Returns:
|
|
* %ax : .text16 segment address
|
|
* %bx : .data16 segment address
|
|
* Corrupts:
|
|
* none
|
|
****************************************************************************
|
|
*/
|
|
.section ".prefix.lib", "awx", @progbits
|
|
.code16
|
|
.globl alloc_basemem
|
|
alloc_basemem:
|
|
/* Preserve registers */
|
|
pushw %fs
|
|
|
|
/* FBMS => %ax as segment address */
|
|
pushw $0x40
|
|
popw %fs
|
|
movw %fs:0x13, %ax
|
|
shlw $6, %ax
|
|
|
|
/* Calculate .data16 segment address */
|
|
subw $_data16_memsz_pgh, %ax
|
|
pushw %ax
|
|
|
|
/* Calculate .text16 segment address */
|
|
subw $_text16_memsz_pgh, %ax
|
|
pushw %ax
|
|
|
|
/* Update FBMS */
|
|
shrw $6, %ax
|
|
movw %ax, %fs:0x13
|
|
|
|
/* Retrieve .text16 and .data16 segment addresses */
|
|
popw %ax
|
|
popw %bx
|
|
|
|
/* Restore registers and return */
|
|
popw %fs
|
|
ret
|
|
.size alloc_basemem, . - alloc_basemem
|
|
|
|
/****************************************************************************
|
|
* free_basemem
|
|
*
|
|
* Free space allocated with alloc_basemem.
|
|
*
|
|
* Parameters:
|
|
* %ax : .text16 segment address
|
|
* %bx : .data16 segment address
|
|
* Returns:
|
|
* %ax : 0 if successfully freed
|
|
* Corrupts:
|
|
* none
|
|
****************************************************************************
|
|
*/
|
|
.section ".text16", "ax", @progbits
|
|
.code16
|
|
.globl free_basemem
|
|
free_basemem:
|
|
/* Preserve registers */
|
|
pushw %fs
|
|
|
|
/* Check FBMS counter */
|
|
pushw %ax
|
|
shrw $6, %ax
|
|
pushw $0x40
|
|
popw %fs
|
|
cmpw %ax, %fs:0x13
|
|
popw %ax
|
|
jne 1f
|
|
|
|
/* Check hooked interrupt count */
|
|
cmpw $0, %cs:hooked_bios_interrupts
|
|
jne 1f
|
|
|
|
/* OK to free memory */
|
|
addw $_text16_memsz_pgh, %ax
|
|
addw $_data16_memsz_pgh, %ax
|
|
shrw $6, %ax
|
|
movw %ax, %fs:0x13
|
|
xorw %ax, %ax
|
|
|
|
1: /* Restore registers and return */
|
|
popw %fs
|
|
ret
|
|
.size free_basemem, . - free_basemem
|
|
|
|
.section ".text16.data", "aw", @progbits
|
|
.globl hooked_bios_interrupts
|
|
hooked_bios_interrupts:
|
|
.word 0
|
|
.size hooked_bios_interrupts, . - hooked_bios_interrupts
|
|
|
|
/****************************************************************************
|
|
* install
|
|
*
|
|
* Install all text and data segments.
|
|
*
|
|
* Parameters:
|
|
* none
|
|
* Returns:
|
|
* %ax : .text16 segment address
|
|
* %bx : .data16 segment address
|
|
* Corrupts:
|
|
* none
|
|
****************************************************************************
|
|
*/
|
|
.section ".prefix.lib", "awx", @progbits
|
|
.code16
|
|
.globl install
|
|
install:
|
|
progress "install:\n"
|
|
/* Preserve registers */
|
|
pushl %esi
|
|
pushl %edi
|
|
pushl %ebp
|
|
/* Allocate space for .text16 and .data16 */
|
|
call alloc_basemem
|
|
/* Image source = %cs:0000 */
|
|
xorl %esi, %esi
|
|
/* Image destination = default */
|
|
xorl %edi, %edi
|
|
/* Allow arbitrary relocation */
|
|
xorl %ebp, %ebp
|
|
/* Install text and data segments */
|
|
call install_prealloc
|
|
/* Restore registers and return */
|
|
popl %ebp
|
|
popl %edi
|
|
popl %esi
|
|
ret
|
|
.size install, . - install
|
|
|
|
/****************************************************************************
|
|
* install_prealloc
|
|
*
|
|
* Install all text and data segments.
|
|
*
|
|
* Parameters:
|
|
* %ax : .text16 segment address
|
|
* %bx : .data16 segment address
|
|
* %esi : Image source physical address (or zero for %cs:0000)
|
|
* %edi : Decompression temporary area physical address (or zero for default)
|
|
* %ebp : Maximum end address for relocation (or zero for no maximum)
|
|
* Corrupts:
|
|
* none
|
|
****************************************************************************
|
|
*/
|
|
.section ".prefix.lib", "awx", @progbits
|
|
.code16
|
|
.globl install_prealloc
|
|
install_prealloc:
|
|
progress "install_prealloc:\n"
|
|
/* Save registers */
|
|
pushal
|
|
pushw %ds
|
|
pushw %es
|
|
cld /* Sanity: clear the direction flag asap */
|
|
|
|
/* Set up %ds for (read-only) access to .prefix */
|
|
pushw %cs
|
|
popw %ds
|
|
|
|
/* Save decompression temporary area physical address */
|
|
pushl %edi
|
|
|
|
/* Install .text16.early and calculate %ecx as offset to next block */
|
|
progress " .text16.early\n"
|
|
pushl %esi
|
|
xorl %esi, %esi
|
|
movw %cs, %si
|
|
shll $4, %esi
|
|
pushl %esi /* Save original %cs:0000 */
|
|
addl $_text16_early_lma, %esi
|
|
movzwl %ax, %edi
|
|
shll $4, %edi
|
|
movl $_text16_early_filesz, %ecx
|
|
movl $_text16_early_memsz, %edx
|
|
call install_block /* .text16.early */
|
|
popl %ecx /* Calculate offset to next block */
|
|
subl %esi, %ecx
|
|
negl %ecx
|
|
popl %esi
|
|
|
|
#ifndef KEEP_IT_REAL
|
|
/* Access high memory by enabling the A20 gate. (We will
|
|
* already have 4GB segment limits as a result of calling
|
|
* install_block.)
|
|
*/
|
|
progress " access_highmem\n"
|
|
pushw %cs
|
|
pushw $1f
|
|
pushw %ax
|
|
pushw $access_highmem
|
|
lret
|
|
1: /* Die if we could not access high memory */
|
|
jnc 3f
|
|
movw $a20_death_message, %si
|
|
xorw %di, %di
|
|
call print_message
|
|
2: jmp 2b
|
|
.section ".prefix.data", "aw", @progbits
|
|
a20_death_message:
|
|
.asciz "\nHigh memory inaccessible - cannot continue\n"
|
|
.size a20_death_message, . - a20_death_message
|
|
.previous
|
|
3:
|
|
#endif
|
|
|
|
/* Open payload (which may not yet be in memory) */
|
|
progress " open_payload\n"
|
|
pushw %cs
|
|
pushw $1f
|
|
pushw %ax
|
|
pushw $open_payload
|
|
lret
|
|
1: /* Die if we could not access the payload */
|
|
jnc 3f
|
|
xorw %di, %di
|
|
movl %esi, %eax
|
|
call print_hex_dword
|
|
movw $payload_death_message, %si
|
|
call print_message
|
|
2: jmp 2b
|
|
.section ".prefix.data", "aw", @progbits
|
|
payload_death_message:
|
|
.asciz "\nPayload inaccessible - cannot continue\n"
|
|
.size payload_death_message, . - payload_death_message
|
|
.previous
|
|
3:
|
|
|
|
/* Calculate physical address of payload (i.e. first source) */
|
|
testl %esi, %esi
|
|
jnz 1f
|
|
movw %cs, %si
|
|
shll $4, %esi
|
|
1: addl %ecx, %esi
|
|
|
|
/* Install .text16.late and .data16 */
|
|
progress " .text16.late\n"
|
|
movl $_text16_late_filesz, %ecx
|
|
movl $_text16_late_memsz, %edx
|
|
call install_block /* .text16.late */
|
|
progress " .data16\n"
|
|
movzwl %bx, %edi
|
|
shll $4, %edi
|
|
movl $_data16_filesz, %ecx
|
|
movl $_data16_memsz, %edx
|
|
call install_block /* .data16 */
|
|
|
|
/* Set up %ds for access to .data16 */
|
|
movw %bx, %ds
|
|
|
|
/* Restore decompression temporary area physical address */
|
|
popl %edi
|
|
|
|
#ifdef KEEP_IT_REAL
|
|
/* Initialise libkir */
|
|
movw %ax, (init_libkir_vector+2)
|
|
lcall *init_libkir_vector
|
|
#else
|
|
/* Find a suitable decompression temporary area, if none specified */
|
|
pushl %eax
|
|
testl %edi, %edi
|
|
jnz 1f
|
|
/* Use INT 15,88 to find the highest available address via INT
|
|
* 15,88. This limits us to around 64MB, which should avoid
|
|
* all of the POST-time memory map failure modes.
|
|
*/
|
|
movb $0x88, %ah
|
|
int $0x15
|
|
movw %ax, %di
|
|
addl $0x400, %edi
|
|
subl $_textdata_memsz_kb, %edi
|
|
shll $10, %edi
|
|
/* Sanity check: if we have ended up below 1MB, use 1MB */
|
|
cmpl $0x100000, %edi
|
|
jae 1f
|
|
movl $0x100000, %edi
|
|
1: popl %eax
|
|
|
|
/* Install .text and .data to temporary area in high memory,
|
|
* prior to reading the E820 memory map and relocating
|
|
* properly.
|
|
*/
|
|
progress " .textdata\n"
|
|
pushl %edi
|
|
movl $_textdata_filesz, %ecx
|
|
movl $_textdata_memsz, %edx
|
|
call install_block
|
|
popl %edi
|
|
|
|
/* Initialise librm at current location */
|
|
progress " init_librm\n"
|
|
movw %ax, (init_librm_vector+2)
|
|
lcall *init_librm_vector
|
|
|
|
/* Call relocate() to determine target address for relocation.
|
|
* relocate() will return with %esi, %edi and %ecx set up
|
|
* ready for the copy to the new location.
|
|
*/
|
|
progress " relocate\n"
|
|
movw %ax, (prot_call_vector+2)
|
|
pushl $relocate
|
|
lcall *prot_call_vector
|
|
popl %edx /* discard */
|
|
|
|
/* Copy code to new location */
|
|
progress " copy\n"
|
|
pushl %edi
|
|
pushw %bx
|
|
movw $copy_bytes, %bx
|
|
call process_bytes
|
|
popw %bx
|
|
popl %edi
|
|
|
|
/* Initialise librm at new location */
|
|
progress " init_librm\n"
|
|
lcall *init_librm_vector
|
|
#endif
|
|
|
|
/* Close access to payload */
|
|
progress " close_payload\n"
|
|
movw %ax, (close_payload_vector+2)
|
|
lcall *close_payload_vector
|
|
|
|
/* Restore registers */
|
|
popw %es
|
|
popw %ds
|
|
popal
|
|
ret
|
|
.size install_prealloc, . - install_prealloc
|
|
|
|
/* Vectors for far calls to .text16 functions. Must be in
|
|
* .data16, since .prefix may not be writable.
|
|
*/
|
|
.section ".data16", "aw", @progbits
|
|
#ifdef KEEP_IT_REAL
|
|
init_libkir_vector:
|
|
.word init_libkir
|
|
.word 0
|
|
.size init_libkir_vector, . - init_libkir_vector
|
|
#else
|
|
init_librm_vector:
|
|
.word init_librm
|
|
.word 0
|
|
.size init_librm_vector, . - init_librm_vector
|
|
prot_call_vector:
|
|
.word prot_call
|
|
.word 0
|
|
.size prot_call_vector, . - prot_call_vector
|
|
#endif
|
|
close_payload_vector:
|
|
.word close_payload
|
|
.word 0
|
|
.size close_payload_vector, . - close_payload_vector
|
|
|
|
/* Dummy routines to open and close payload */
|
|
.section ".text16.early.data", "aw", @progbits
|
|
.weak open_payload
|
|
.weak close_payload
|
|
open_payload:
|
|
close_payload:
|
|
clc
|
|
lret
|
|
.size open_payload, . - open_payload
|
|
.size close_payload, . - close_payload
|
|
|
|
/****************************************************************************
|
|
* uninstall
|
|
*
|
|
* Uninstall all text and data segments.
|
|
*
|
|
* Parameters:
|
|
* %ax : .text16 segment address
|
|
* %bx : .data16 segment address
|
|
* Returns:
|
|
* none
|
|
* Corrupts:
|
|
* none
|
|
****************************************************************************
|
|
*/
|
|
.section ".text16", "ax", @progbits
|
|
.code16
|
|
.globl uninstall
|
|
uninstall:
|
|
call free_basemem
|
|
ret
|
|
.size uninstall, . - uninstall
|
|
|
|
|
|
|
|
/* File split information for the compressor */
|
|
#if COMPRESS
|
|
#define PACK_OR_COPY "PACK"
|
|
#else
|
|
#define PACK_OR_COPY "COPY"
|
|
#endif
|
|
.section ".zinfo", "a", @progbits
|
|
.ascii "COPY"
|
|
.long _prefix_lma
|
|
.long _prefix_filesz
|
|
.long _max_align
|
|
.ascii PACK_OR_COPY
|
|
.long _text16_early_lma
|
|
.long _text16_early_filesz
|
|
.long _max_align
|
|
.ascii "PAYL"
|
|
.long 0
|
|
.long 0
|
|
.long _payload_align
|
|
.ascii "COPY"
|
|
.long _pprefix_lma
|
|
.long _pprefix_filesz
|
|
.long _max_align
|
|
.ascii PACK_OR_COPY
|
|
.long _text16_late_lma
|
|
.long _text16_late_filesz
|
|
.long _max_align
|
|
.ascii PACK_OR_COPY
|
|
.long _data16_lma
|
|
.long _data16_filesz
|
|
.long _max_align
|
|
.ascii PACK_OR_COPY
|
|
.long _textdata_lma
|
|
.long _textdata_filesz
|
|
.long _max_align
|
|
|
|
.weak _payload_align
|
|
.equ _payload_align, 1
|