Linux 0.11內核bootsect.s和loader.s的移植爲AT&T彙編

感覺在linux使用與GCC內置AT&T不同的AS86碼格格不入，所以做了移植。

1、bootsect.s的移植：

/*----------------------------------------------------------------------------*/ .equ SYSSIZE, 0x3000 /*----------------------------------------------------------------------------*/ .globl begtext, begdata, begbss, endtext, enddata, endbss .text begtext: .data begdata: .bss begbss: /*----------------------------------------------------------------------------*/ .equ SETUPLEN, 4 .equ BOOTSEG, 0x07c0 .equ INITSEG, 0x9000 .equ SETUPSEG, 0x9020 .equ SYSSEG, 0x1000 .equ ENDSEG, SYSSEG + SYSSIZE .equ ROOT_DEV, 0x000 /*----------------------------------------------------------------------------*/ .code16 .text .globl start start: mov $BOOTSEG, %ax mov %ax, %ds mov $INITSEG, %ax mov %ax, %es mov $256, %cx sub %si, %si sub %di, %di rep movsw ljmp $INITSEG, $go go: mov %cs, %ax mov %ax, %ds mov %ax, %es mov %ax, %ss mov $0xFF00, %sp load_setup: mov $0x0000, %dx mov $0x0002, %cx mov $0x0200, %bx mov $(0x0200+SETUPLEN), %ax int $0x13 jnc ok_load_setup mov $0x0000, %dx mov $0x0000, %ax int $0x13 jmp load_setup ok_load_setup: mov $0x00, %dl mov $0x0800, %ax int $0x13 mov $0x00, %ch mov %cx, (sectors) mov $INITSEG, %ax mov %ax, %es mov $0x03, %ah xor %bh, %bh int $0x10 mov $24, %cx mov $0x0007, %bx mov $msg1, %bp mov $0x1301, %ax int $0x10 mov $SYSSEG, %ax mov %ax, %es call read_it call kill_motor mov (root_dev), %ax cmp $0, %ax jne root_defined mov (sectors), %bx mov $0x0208, %ax cmp $15, %bx je root_defined mov $0x021c, %ax cmp $18, %bx je root_defined jmp . root_defined: mov %ax, (root_dev) ljmp $SETUPSEG, $0 /*----------------------------------------------------------------------------*/ sread: .word 1+SETUPLEN head: .word 0 track: .word 0 /*----------------------------------------------------------------------------*/ read_it: mov %es, %ax test $0x0fff, %ax jne . xor %bx, %bx rp_read: mov %es, %ax cmp $ENDSEG, %ax jb ok1_read ret ok1_read: mov (sectors), %ax sub (sread), %ax mov %ax, %cx shl $9, %cx add %bx, %cx jnc ok2_read je ok2_read xor %ax, %ax sub %bx, %ax shr $9, %ax ok2_read: call read_track mov %ax, %cx add (sread), %ax cmp (sectors), %ax jne ok3_read mov $1, %ax sub (head), %ax jne ok4_read incw (track) ok4_read: mov %ax, (head) xor %ax, %ax ok3_read: mov %ax, (sread) shl $9, %cx add %cx, %bx jnc rp_read mov %es, %ax add $0x1000, %ax mov %ax, %es xor %bx, %bx jmp rp_read read_track: push %ax push %bx push %cx push %dx mov (track), %dx mov (sread), %cx inc %cx mov %dl, %ch mov (head), %dx mov %dl, %dh mov $0, %dl and $0x0100, %dx mov $2, %ah int $0x13 jc bad_rt pop %dx pop %cx pop %bx pop %ax ret bad_rt: mov $0, %ax mov $0, %dx int $0x13 pop %dx pop %cx pop %bx pop %ax jmp read_track kill_motor: push %dx mov $0x3f2, %dx mov $0, %al outb %al, %dx pop %dx ret sectors: .word 0 msg1: .byte 13, 10 .ascii "Loading system ..." .byte 13, 10, 13, 10 .org 508 root_dev: .word ROOT_DEV boot_flag: .word 0xAA55 .text endtext: .data enddata: .bss endbss: /*----------------------------------------------------------------------------*/

2、setup.s的移植：

/*----------------------------------------------------------------------------*/ .equ INITSEG, 0x9000 .equ SYSSEG, 0x1000 .equ SETUPSEG, 0x9020 /*----------------------------------------------------------------------------*/ .globl begtext, begdata, begbss, endtext, enddata, endbss .text begtext: .data begdata: .bss begbss: /*----------------------------------------------------------------------------*/ .code16 .text .globl start start: mov $INITSEG, %ax mov %ax, %ds mov $0x03, %ah xor %bh, %bh int $0x10 mov %dx, (0) mov $0x88, %ah int $0x15 mov %ax, (2) mov $0x0f, %ah int $0x10 mov %bx, (4) mov %ax, (6) mov $0x12, %ah mov $0x10, %bl int $0x10 mov %ax, (8) mov %bx, (10) mov %cx, (12) mov $0x0000, %ax mov %ax, %ds lds (4*0x41), %si mov $INITSEG, %ax mov %ax, %es mov $0x0080, %di mov $0x10, %cx rep movsb mov $0x0000, %ax mov %ax, %ds lds (4*0x46), %si mov $INITSEG, %ax mov %ax, %es mov $0x0090, %di mov $0x10, %cx rep movsb mov $0x1500, %ax mov $0x81, %dl int $0x13 jc no_disk1 cmp $3, %ah je is_disk1 no_disk1: mov $INITSEG, %ax mov %ax, %es mov $0x0090, %di mov $0x10, %cx mov $0x00, %ax rep stosb is_disk1: cli mov $0x0000, %ax cld do_move: mov %ax, %es add $0x1000, %ax cmp $0x9000, %ax jz end_move mov %ax, %ds sub %di, %di sub %si, %si mov $0x8000, %cx rep movsw jmp do_move end_move: mov $SETUPSEG, %ax mov %ax, %ds lidt (idt_48) lgdt (gdt_48) call empty_8042 mov $0xD1, %al out %al, $0x64 call empty_8042 mov $0xDF, %al out %al, $0x60 call empty_8042 mov $0x11, %al out %al, $0x20 .word 0x00eb, 0x00eb out %al, $0xA0 .word 0x00eb, 0x00eb mov $0x20, %al out %al, $0x21 .word 0x00eb, 0x00eb mov $0x28, %al out %al, $0xA1 .word 0x00eb, 0x00eb mov $0x04, %al out %al, $0x21 .word 0x00eb, 0x00eb mov $0x02, %al out %al, $0xA1 .word 0x00eb, 0x00eb mov $0x01, %al out %al, $0x21 .word 0x00eb, 0x00eb out %al, $0xA1 .word 0x00eb, 0x00eb mov $0xFF, %al out %al, $0x21 .word 0x00eb, 0x00eb out %al, $0xA1 mov %cr0, %eax or $0x0001, %eax mov %eax, %cr0 ljmp $8, $0 empty_8042: .word 0x00eb, 0x00eb in $0x64, %al test $2, %al jnz empty_8042 ret gdt: .word 0, 0, 0, 0 .word 0x07FF .word 0x0000 .word 0x9A00 .word 0x00C0 .word 0x07FF .word 0x0000 .word 0x9200 .word 0x00C0 idt_48: .word 0 .word 0, 0 gdt_48: .word 0x800 .word 512+gdt, 0x9 .text endtext: .data enddata: .bss endbss: /*----------------------------------------------------------------------------*/

3、Makefile的修改：

RAMDISK =#-DRAMDISK=512 CC =gcc -mcpu=i386 $(RAMDISK) LD =ld OBJCOPY =objcopy OBJDUMP =objdump CPP =cpp -nostdinc -Iinclude CFLAGS =-Wall -O2 -g -fomit-frame-pointer LDFLAGS =-m elf_i386 -Ttext 0 -e startup_32 TRIMFLAGS =-R .pdr -R .comment -R .note -S -O binary ROOT_DEV =FLOPPY ARCHIVES =kernel/kernel.o mm/mm.o fs/fs.o DRIVERS =kernel/blk_drv/blk_drv.a kernel/chr_drv/chr_drv.a MATH =kernel/math/math.a LIBS =lib/lib.a .c.s: $(CC) $(CFLAGS) -nostdinc -Iinclude -S -o $*.s $< .s.o: $(AS) -c -o $*.o $< .c.o: $(CC) $(CFLAGS) -nostdinc -Iinclude -c -o $*.o $< all : Image Image: boot/bootsect boot/setup tools/system tools/build $(OBJCOPY) $(TRIMFLAGS) tools/system tools/kernel tools/build boot/bootsect boot/setup tools/kernel $(ROOT_DEV) > Image rm -f tools/kernel sync disk: Image dd bs=8192 if=Image of=/dev/fd0 tools/build: tools/build.c $(CC) $(CFLAGS) -o tools/build tools/build.c boot/bootsect : boot/bootsect.s $(CC) -c $< -o boot/bootsect.o $(LD) -Ttext 0x0000 -e start boot/bootsect.o -o boot/bootsect.elf $(OBJCOPY) $(TRIMFLAGS) boot/bootsect.elf $@ boot/setup : boot/setup.s $(CC) -c $< -o boot/setup.o $(LD) -Ttext 0x0000 -e start boot/setup.o -o boot/setup.elf $(OBJCOPY) $(TRIMFLAGS) boot/setup.elf $@ boot/head.o : boot/head.s gcc -Iinclude -traditional -c $< -o $@ tools/system : boot/head.o init/main.o $(ARCHIVES) $(DRIVERS) $(MATH) $(LIBS) $(LD) $(LDFLAGS) boot/head.o init/main.o $(ARCHIVES) $(DRIVERS) $(MATH) $(LIBS) -o tools/system nm tools/system | grep -v '/(compiled/)/|/(/.o$$/)/|/( [aU] /)/|/(/./.ng$$/)/|/(LASH[RL]DI/)'| sort > System.map kernel/math/math.a : (cd kernel/math; make) kernel/blk_drv/blk_drv.a : (cd kernel/blk_drv; make) kernel/chr_drv/chr_drv.a : (cd kernel/chr_drv; make) kernel/kernel.o : (cd kernel; make) mm/mm.o : (cd mm; make) fs/fs.o : (cd fs; make) lib/lib.a : (cd lib; make) tmp.s : boot/bootsect.s tools/system (echo -n "SYSSIZE = (";ls -l tools/system | grep system | cut -c25-31 | tr '/012' ' '; echo "+ 15 ) / 16") > tmp.s cat boot/bootsect.s >> tmp.s clean : rm -f tmp_make core boot/bootsect boot/setup rm -f init/*.o tools/system tools/build boot/*.o boot/*.elf (cd kernel;make clean) (cd mm;make clean) (cd fs;make clean) (cd lib;make clean) backup : clean (cd .. ; tar cf - linux | compress16 - > backup.Z) sync dep: sed '//#/#/# Dependencies/q' < Makefile > tmp_make (for i in init/*.c;do echo -n "init/";$(CPP) -M $$i;done) >> tmp_make cp tmp_make Makefile (cd kernel; make dep) (cd fs; make dep) (cd mm; make dep) realclean : clean @rm -f Image System.map everything : realclean all .PHONY : everything clean realclean all copy ### Dependencies:

只做了下搬運工，參考如下：

1、http://www.oldlinux.org/oldlinux/viewthread.php?tid=3965&extra=page%3D1

2、"Professional Assembly Language', Richard Blum

3、《自己寫操作系統》，於淵

4、《使用開源自己動手寫操作系統》，楊文博