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著名的linux英雄站点的文档打包

       DS:[0x1FF] = 0;<br>
       // get equipment list<br>
       // http://www.ctyme.com/intr/rb-0575.htm<br>
       int11h();<br>
       if (has psmouse) {<br>
               DS:[0x1FF] = 0xAA;<br>
       }<br>
<br>
#ifdef CONFIG_APM<br>
       // check for APM BIOS<br>
<br>
       DS:[0x40] = 0;<br>
       // Advanced Power Management v1.0+ - installation check<br>
       // http://www.ctyme.com/intr/rb-1394.htm<br>
       int15h/AX=5300h(BX=0);<br>
       // check both CF and BX for APM support<br>
       if (APM && 32-bit protected mode interface supported) {<br>
               int15h/AX=5304h(BX=0);  // disconnect interface<br>
               try {<br>
                       // clear return values first<br>
                       clear EBX, CX, DX, ESI, DI;<br>
                       // connect 32bit protect mode APM interface<br>
                       // http://www.ctyme.com/intr/rb-1397.htm<br>
                       int15h/AX=5303h(BX=0);<br>
                       if (supported) {<br>
                               DS:[0x42] = 32-bit code segment base address;<br>
                               DS:[0x44] = offset of entry point;<br>
                               DS:[0x48] = 16-bit code segment base address;<br>
                               DS:[0x4A] = 16-bit data segment base address;<br>
                               DS:[0x4E] = APM BIOS code segment length;<br>
                               DS:[0x52] = APM BIOS data segment length;<br>
                               int15h/AX=5300h(BX=0);  // check again<br>
                               if (APM supported) {<br>
                                       INITSET:[0x40] = APM version;<br>
                                       INITSET:[0x4C] = APM flags;<br>
                               }<br>
                               else {  // should not happen<br>
                                       // disconnect interface<br>
                                       int15h/AX=5304h(BX=0);<br>
                               }<br>
                       }<br>
                       else {<br>
                               // clear 32bit support<br>
                               INITSET:[0x4C] &= ~0x0002;<br>
                       }<br>
               }<br>
       }<br>
#endif<br>
<br>
       // call mode switch<br>
       if (realmode_swtch) {<br>
               far realmode_swtch();   // mode switch hook<br>
       }<br>
       else {<br>
               far default_switch();   // see below<br>
       }<br>
<br>
       // set code32: 0x100000 for big kernel,  otherwise 0x1000<br>
       (double word) code32 = code32_start;<br>
       if (!(loadflags & LOADED_HIGH)) {<br>
               // normal low loaded zImage<br>
               move start_sys_seg:0 to (0100:0 ... CS-DELTA_INITSEG:0);<br>
               //      move 0x1000 bytes each time<br>
       }<br>
       if (CS!=SETUPSEG) {<br>
               cli;    // disable interrupts<br>
<br>
               // store new SS in DX<br>
               DX = SS;<br>
               AX = CS - DELTA_INITSEG;<br>
               if (DX&gt;=AX) {<br>
                       DX = DX + INITSEG - AX; // i.e. SS-CS+SETUPSEG<br>
               }<br>
<br>
               // move CS-DELTA_INITSEG:0 to INITSEG:0 (setup_move_size bytes)<br>
               // TODO: why not do this in one step?<br>
               ES = INITSEG;<br>
               move _DOWNWARD_ from CS-DELTA_INITSEG:setup_move_size-1 to<br>
                       (INITSEG:setup_move_size-1<br>
                       ... INITSEG:move_self_here+0x200);<br>
               // setup_move_size-move_self_here-0x200 bytes<br>
               // INITSEG:move_self_here+0x200 = SETUPSEG:move_self_here<br>
               goto SETUPSEG:move_self_here;<br>
move_self_here:<br>
               move the rest to INITSEG:move_self_here+0x200-1 ... INITSEG:0;<br>
               // move_self_here+0x200 bytes<br>
               DS = SETUPSEG;<br>
               SS = DX;<br>
       }<br>
       // CS==SETUPSEG is true now<br>
<br>
// Protected Mode Basics<br>
       // http://x86.ddj.com/articles/pmbasics/tspec_a1_doc.htm<br>
<br>
       lidt    idt_48; // load idt with 0, 0;<br>
       // new code added here in linux 2.4<br>
       lgdt    gdt_48; // load gdt with whatever appropriate;<br>
<br>
       // enable A20<br>
       empty_8042();<br>
       outportb(0x64, 0xD1);   // command write<br>
       empty_8042();<br>
       outportb(0x60, 0xDF);   // A20 on<br>
       empty_8042();<br>
<br>
#define TEST_ADDR 0x7C<br>
<br>
       // test A20<br>
       GS = AX = 0xFFFF;<br>
       BX = 0:[TEST_ADDR];<br>
       do {<br>
               0:[TEST_ADDR] = ++AX;<br>
       } while (AX==GS:[TEST_ADDR+0x10]);<br>
       0:[TEST_ADDR] = BX;<br>
<br>
       // reset coprocessor<br>
       outportb(0xF0, 0);<br>
       delay();<br>
       outportb(0xF1, 0);<br>
       delay();<br>
<br>
       // reprogram the interrupts<br>
       outportb(0x20, 0x11);   // initialize 8259A-1<br>
       delay();<br>
       outportb(0xA0, 0x11);   // initialize 8259A-2<br>
       delay();<br>
       outportb(0x21, 0x20);   // start of hardware int's (0x20)<br>
       delay();<br>
       outportb(0xA1, 0x28);   // start of hardware int's 2 (0x28)<br>
       delay();<br>
       outportb(0x21, 0x04);   // 8259-1 is master<br>
       delay();<br>
       outportb(0xA1, 0x02);   // 8259-2 is slave<br>
       delay();<br>
       outportb(0x21, 0x01);   // 8086 mode<br>
       delay();<br>
       outportb(0xA1, 0x01);   // 8086 mode<br>
       delay();<br>
       outportb(0xA1, 0xFF);   // mask off all interrupts for now<br>
       delay();<br>
       outportb(0x21, 0xFB);   // mask all irq's but irq2, which is cascaded<br>
<br>
       // protected mode!<br>
       mov     ax, #1;<br>
       lmsw    ax;<br>
       jmp     flush_instr;<br>
flush_instr:<br>
       xor     bx, bx;<br>
}<br>
<br>
////////////////////////////////////////////////////////////////////<br>
{<br>
       db      0x66, 0xea<br>
code32:<br>
       dd      0x1000<br>
       dw      __KERNEL_CS     // 0x10, defined in asm-i386/segment.h<br>
//      goto 10:1000 or 10:100000<br>
<br>
kernel_version:<br>
       .ascii  UTS_RELEASE     // defined in makefile<br>
       .ascii  "("<br>
       .ascii  LINUX_COMPILE_BY<br>
       .ascii  "@"<br>
       .ascii  LINUX_COMPILE_HOST<br>
       .ascii  ")"<br>
       .ascii  UTS_VERSION<br>
       db      0<br>
}<br>
<br>
////////////////////////////////////////////////////////////////////<br>
// default real mode switch routine<br>
far default_switch()<br>
{<br>
       cli;<br>
       outportb(0x70, 0x80);   // disable NMI<br>
}<br>
<br>
////////////////////////////////////////////////////////////////////<br>
// get called when using bootsect loader _AND_ have bzImage to load<br>
far bootsect_helper(ES)<br>
{<br>
       if (bootsect_es==0) {<br>
               type_of_loader = 0x20;  // bootsect-loader, version 0<br>
               AX = ES &gt;&gt; 4;<br>
               CS:[bootsect_src_base+2] = AH;<br>
               bootsect_es = ES;<br>
               AX = ES - SYSSEG;<br>
       }<br>
       else {<br>
               if (BX==0) {       // 64K aligned<br>
                       // copy extended memory<br>
                       // http://www.ctyme.com/intr/rb-1527.htm<br>
                       try {<br>
                               int15h/AX=87h(CX=0x8000,<br>
                                       ES:SI=CS:bootsect_gdt);<br>
                       }<br>
                       catch {<br>
bootsect_panic:<br>
                               prtstr("INT15 refuses to access high memory."<br>
                                       " Giving up.");<br>
                               halt;<br>
                       }<br>
                       ES = bootsect_es;<br>
                       CS:[bootsect_dst_base+2]++;<br>
               }<br>
               AH = CS:[bootsect_dst_base+2] &lt;&lt; 4;<br>
               AL = 0;<br>
       }<br>
}<br>
<br>
////////////////////////////////////////////////////////////////////<br>
{<br>
bootsect_gdt:<br>
       .word   0, 0, 0, 0<br>
       .word   0, 0, 0, 0<br>
bootsect_src:<br>
       .word   0xFFFF<br>
bootsect_src_base:<br>
       .byte   0, 0, 1         ! base = 0x010000<br>
       .byte   0x93            ! typbyte<br>
       .word   0               ! limit16, base24 =0<br>
bootsect_dst:<br>
       .word   0xFFFF<br>
bootsect_dst_base:<br>
       .byte   0, 0, 0x10      ! base = 0x100000<br>
       .byte   0x93            ! typbyte<br>
       .word   0               ! limit16, base24 =0<br>
       .word   0, 0, 0, 0      ! used by BIOS<br>
       .word   0, 0, 0, 0<br>
bootsect_es:<br>
       .word   0<br>
}<br>
<br>
////////////////////////////////////////////////////////////////////<br>
// check that the keyboard command queue is empty<br>
empty_8042()<br>
{<br>
       timeout = 0xFFFFFF;             // local variable<br>
       for (;;) {<br>
               if (--timeout==0) return;<br>
               delay();<br>
               inportb(0x64, AL);      // 8042 status port<br>
               if (AL & 1) {           // output buffer<br>
                       delay();<br>
                       inportb(0x60, .);<br>
                       continue;<br>
               }<br>
               if (!(AL & 2)) return;  // input buffer<br>
       }<br>
}<br>
<br>
////////////////////////////////////////////////////////////////////<br>
// read the CMOS clock, return the seconds in AL<br>
gettime()<br>
{<br>
       // get real-time clock time<br>
       // http://www.ctyme.com/intr/rb-2273.htm<br>
       int1Ah/AH=02h();        // DH = seconds (in BCD)<br>
       AL = DH & 0x0F;<br>
       AH = DH &gt;&gt; 4;<br>
       AAD;<br>
}<br>
<br>
////////////////////////////////////////////////////////////////////<br>
delay() { /* needed after doing I/O */ }<br>
<br>
////////////////////////////////////////////////////////////////////<br>
{<br>
gdt:<br>
       .word   0,0,0,0         ! dummy<br>
       .word   0,0,0,0         ! unused<br>
<br>
       .word   0xFFFF          ! 4Gb - (0x100000*0x1000 = 4Gb)<br>
       .word   0x0000          ! base address=0<br>
       .word   0x9A00          ! code read/exec<br>
       .word   0x00CF          ! granularity=4096, 386 (+5th nibble of limit)<br>
<br>
       .word   0xFFFF          ! 4Gb - (0x100000*0x1000 = 4Gb)<br>
       .word   0x0000          ! base address=0<br>
       .word   0x9200          ! data read/write<br>
       .word   0x00CF          ! granularity=4096, 386 (+5th nibble of limit)<br>
idt_48:<br>
       .word   0               ! idt limit=0<br>
       .word   0, 0            ! idt base=0L<br>
gdt_48:<br>
       .word   0x800           ! gdt limit=2048, 256 GDT entries<br>
       .word   512+gdt, 0x9    ! gdt base = 0x9XXXX<br>
// +512 because of bootsect<br>
}<br>
<br>
////////////////////////////////////////////////////////////////////<br>
// Included video setup & detection code "video.S"<br>
/*<br>
Positions of various video parameters passed to the kernel<br>
       (see also include/linux/tty.h)<br>
CS-DELTA_INITSEG segment<br>
#define PARAM_CURSOR_POS        0x00<br>
#define PARAM_VIDEO_PAGE        0x04<br>
#define PARAM_VIDEO_MODE        0x06<br>
#define PARAM_VIDEO_COLS        0x07<br>
#define PARAM_VIDEO_EGA_BX      0x0a<br>
#define PARAM_VIDEO_LINES       0x0e<br>
#define PARAM_HAVE_VGA          0x0f<br>
#define PARAM_FONT_POINTS       0x10<br>
#define PARAM_LFB_WIDTH         0x12<br>
#define PARAM_LFB_HEIGHT        0x14<br>
#define PARAM_LFB_DEPTH         0x16<br>
#define PARAM_LFB_BASE          0x18<br>
#define PARAM_LFB_SIZE          0x1c<br>
#define PARAM_LFB_LINELENGTH    0x24<br>