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Text File | 1993-12-01 | 17.3 KB | 870 lines

! ! setup.S Copyright (C) 1991, 1992 Linus Torvalds ! ! setup.s is responsible for getting the system data from the BIOS, ! and putting them into the appropriate places in system memory. ! both setup.s and system has been loaded by the bootblock. ! ! This code asks the bios for memory/disk/other parameters, and ! puts them in a "safe" place: 0x90000-0x901FF, ie where the ! boot-block used to be. It is then up to the protected mode ! system to read them from there before the area is overwritten ! for buffer-blocks. ! ! Move PS/2 aux init code to psaux.c ! (troyer@saifr00.cfsat.Honeywell.COM) 03Oct92 ! ! some changes and additional features by Christoph Niemann, March 1993 ! (niemann@rubdv15.ETDV.Ruhr-Uni-Bochum.De) ! ! NOTE! These had better be the same as in bootsect.s! #include <linux/config.h> #include <linux/segment.h> #ifndef SVGA_MODE #define SVGA_MODE ASK_VGA #endif INITSEG = DEF_INITSEG ! we move boot here - out of the way SYSSEG = DEF_SYSSEG ! system loaded at 0x10000 (65536). SETUPSEG = DEF_SETUPSEG ! this is the current segment .globl begtext, begdata, begbss, endtext, enddata, endbss .text begtext: .data begdata: .bss begbss: .text entry start start: ! ok, the read went well so we get current cursor position and save it for ! posterity. mov ax,#INITSEG ! this is done in bootsect already, but... mov ds,ax ! Get memory size (extended mem, kB) mov ah,#0x88 int 0x15 mov [2],ax ! set the keyboard repeat rate to the max mov ax,#0x0305 xor bx,bx ! clear bx int 0x16 ! check for EGA/VGA and some config parameters mov ah,#0x12 mov bl,#0x10 int 0x10 mov [8],ax mov [10],bx mov [12],cx mov ax,#0x5019 cmp bl,#0x10 je novga mov ax,#0x1a00 ! Added check for EGA/VGA discrimination int 0x10 mov bx,ax mov ax,#0x5019 cmp bl,#0x1a ! 1a means VGA, anything else EGA or lower jne novga call chsvga novga: mov [14],ax mov ah,#0x03 ! read cursor pos xor bh,bh ! clear bh int 0x10 ! save it in known place, con_init fetches mov [0],dx ! it from 0x90000. ! Get video-card data: mov ah,#0x0f int 0x10 mov [4],bx ! bh = display page mov [6],ax ! al = video mode, ah = window width ! Get hd0 data xor ax,ax ! clear ax mov ds,ax lds si,[4*0x41] mov ax,#INITSEG mov es,ax mov di,#0x0080 mov cx,#0x10 cld rep movsb ! Get hd1 data xor ax,ax ! clear ax mov ds,ax lds si,[4*0x46] mov ax,#INITSEG mov es,ax mov di,#0x0090 mov cx,#0x10 cld rep movsb ! Check that there IS a hd1 :-) mov ax,#0x01500 mov dl,#0x81 int 0x13 jc no_disk1 cmp ah,#3 je is_disk1 no_disk1: mov ax,#INITSEG mov es,ax mov di,#0x0090 mov cx,#0x10 xor ax,ax ! clear ax cld rep stosb is_disk1: ! check for PS/2 pointing device mov ax,#INITSEG mov ds,ax mov [0x1ff],#0 ! default is no pointing device int 0x11 ! int 0x11: equipment determination test al,#0x04 ! check if pointing device installed jz no_psmouse mov [0x1ff],#0xaa ! device present no_psmouse: ! now we want to move to protected mode ... cli ! no interrupts allowed ! mov al,#0x80 ! disable NMI for the bootup sequence out #0x70,al ! first we move the system to its rightful place mov ax,#0x100 ! start of destination segment mov bx,#0x1000 ! start of source segment cld ! 'direction'=0, movs moves forward do_move: mov es,ax ! destination segment add ax,#0x100 cmp ax,#0x9000 jz end_move mov ds,bx ! source segment add bx,#0x100 sub di,di sub si,si mov cx,#0x800 rep movsw jmp do_move ! then we load the segment descriptors end_move: mov ax,#SETUPSEG ! right, forgot this at first. didn't work :-) mov ds,ax lidt idt_48 ! load idt with 0,0 lgdt gdt_48 ! load gdt with whatever appropriate ! that was painless, now we enable A20 call empty_8042 mov al,#0xD1 ! command write out #0x64,al call empty_8042 mov al,#0xDF ! A20 on out #0x60,al call empty_8042 ! make sure any possible coprocessor is properly reset.. xor ax,ax out #0xf0,al call delay out #0xf1,al call delay ! well, that went ok, I hope. Now we have to reprogram the interrupts :-( ! we put them right after the intel-reserved hardware interrupts, at ! int 0x20-0x2F. There they won't mess up anything. Sadly IBM really ! messed this up with the original PC, and they haven't been able to ! rectify it afterwards. Thus the bios puts interrupts at 0x08-0x0f, ! which is used for the internal hardware interrupts as well. We just ! have to reprogram the 8259's, and it isn't fun. mov al,#0x11 ! initialization sequence out #0x20,al ! send it to 8259A-1 call delay out #0xA0,al ! and to 8259A-2 call delay mov al,#0x20 ! start of hardware int's (0x20) out #0x21,al call delay mov al,#0x28 ! start of hardware int's 2 (0x28) out #0xA1,al call delay mov al,#0x04 ! 8259-1 is master out #0x21,al call delay mov al,#0x02 ! 8259-2 is slave out #0xA1,al call delay mov al,#0x01 ! 8086 mode for both out #0x21,al call delay out #0xA1,al call delay mov al,#0xFF ! mask off all interrupts for now out #0xA1,al call delay mov al,#0xFB ! mask all irq's but irq2 which out #0x21,al ! is cascaded ! well, that certainly wasn't fun :-(. Hopefully it works, and we don't ! need no steenking BIOS anyway (except for the initial loading :-). ! The BIOS-routine wants lots of unnecessary data, and it's less ! "interesting" anyway. This is how REAL programmers do it. ! ! Well, now's the time to actually move into protected mode. To make ! things as simple as possible, we do no register set-up or anything, ! we let the gnu-compiled 32-bit programs do that. We just jump to ! absolute address 0x00000, in 32-bit protected mode. ! ! Note that the short jump isn't strictly needed, althought there are ! reasons why it might be a good idea. It won't hurt in any case. ! mov ax,#0x0001 ! protected mode (PE) bit lmsw ax ! This is it! jmp flush_instr flush_instr: jmpi 0x1000,KERNEL_CS ! jmp offset 1000 of segment 0x10 (cs) ! This routine checks that the keyboard command queue is empty ! (after emptying the output buffers) ! ! No timeout is used - if this hangs there is something wrong with ! the machine, and we probably couldn't proceed anyway. empty_8042: call delay in al,#0x64 ! 8042 status port test al,#1 ! output buffer? jz no_output call delay in al,#0x60 ! read it jmp empty_8042 no_output: test al,#2 ! is input buffer full? jnz empty_8042 ! yes - loop ret ! ! Read a key and return the (US-)ascii code in al, scan code in ah ! getkey: xor ah,ah int 0x16 ret ! ! Read a key with a timeout of 30 seconds. The cmos clock is used to get ! the time. ! getkt: call gettime add al,#30 ! wait 30 seconds cmp al,#60 jl lminute sub al,#60 lminute: mov cl,al again: mov ah,#0x01 int 0x16 jnz getkey ! key pressed, so get it call gettime cmp al,cl jne again mov al,#0x20 ! timeout, return default char `space' ret ! ! Flush the keyboard buffer ! flush: mov ah,#0x01 int 0x16 jz empty xor ah,ah int 0x16 jmp flush empty: ret ! ! Read the cmos clock. Return the seconds in al ! gettime: push cx mov ah,#0x02 int 0x1a mov al,dh ! dh contains the seconds and al,#0x0f mov ah,dh mov cl,#0x04 shr ah,cl aad pop cx ret ! ! Delay is needed after doing i/o ! delay: .word 0x00eb ! jmp $+2 ret ! Routine trying to recognize type of SVGA-board present (if any) ! and if it recognize one gives the choices of resolution it offers. ! If one is found the resolution chosen is given by al,ah (rows,cols). chsvga: cld push ds push cs mov ax,[0x01fa] pop ds mov modesave,ax mov ax,#0xc000 mov es,ax mov ax,modesave cmp ax,#NORMAL_VGA je defvga cmp ax,#EXTENDED_VGA je vga50 cmp ax,#ASK_VGA jne svga lea si,msg1 call prtstr call flush nokey: call getkt cmp al,#0x0d ! enter ? je svga ! yes - svga selection cmp al,#0x20 ! space ? je defvga ! no - repeat call beep jmp nokey defvga: mov ax,#0x5019 pop ds ret /* extended vga mode: 80x50 */ vga50: mov ax,#0x1112 xor bl,bl int 0x10 ! use 8x8 font set (50 lines on VGA) mov ax,#0x1200 mov bl,#0x20 int 0x10 ! use alternate print screen mov ax,#0x1201 mov bl,#0x34 int 0x10 ! turn off cursor emulation mov ah,#0x01 mov cx,#0x0607 int 0x10 ! turn on cursor (scan lines 6 to 7) pop ds mov ax,#0x5032 ! return 80x50 ret /* extended vga mode: 80x28 */ vga28: pop ax ! clean the stack mov ax,#0x1111 xor bl,bl int 0x10 ! use 9x14 fontset (28 lines on VGA) mov ah, #0x01 mov cx,#0x0b0c int 0x10 ! turn on cursor (scan lines 11 to 12) pop ds mov ax,#0x501c ! return 80x28 ret /* svga modes */ svga: cld lea si,id9GXE ! Check for the #9GXE (jyanowit@orixa.mtholyoke.edu,thanks dlm40629@uxa.cso.uiuc.edu) mov di,#0x49 ! id string is at c000:049 mov cx,#0x11 ! length of "Graphics Power By" repe cmpsb jne of1280 is9GXE: lea si,dsc9GXE ! table of descriptions of video modes for BIOS lea di,mo9GXE ! table of sizes of video modes for my BIOS br selmod ! go ask for video mode of1280: cld lea si,idf1280 ! Check for Orchid F1280 (dingbat@diku.dk) mov di,#0x10a ! id string is at c000:010a mov cx,#0x21 ! length repe cmpsb jne nf1280 isVRAM: lea si,dscf1280 lea di,mof1280 br selmod nf1280: lea si,idVRAM mov di,#0x10a mov cx,#0x0c repe cmpsb je isVRAM cld lea si,idati ! Check ATI 'clues' mov di,#0x31 mov cx,#0x09 repe cmpsb jne noati lea si,dscati lea di,moati br selmod noati: mov ax,#0x200f ! Check Ahead 'clues' mov dx,#0x3ce out dx,ax inc dx in al,dx cmp al,#0x20 je isahed cmp al,#0x21 jne noahed isahed: lea si,dscahead lea di,moahead br selmod noahed: mov dx,#0x3c3 ! Check Chips & Tech. 'clues' in al,dx or al,#0x10 out dx,al mov dx,#0x104 in al,dx mov bl,al mov dx,#0x3c3 in al,dx and al,#0xef out dx,al cmp bl,[idcandt] jne nocant lea si,dsccandt lea di,mocandt br selmod nocant: mov dx,#0x3d4 ! Check Cirrus 'clues' mov al,#0x0c out dx,al inc dx in al,dx mov bl,al xor al,al out dx,al dec dx mov al,#0x1f out dx,al inc dx in al,dx mov bh,al xor ah,ah shl al,#4 mov cx,ax mov al,bh shr al,#4 add cx,ax shl cx,#8 add cx,#6 mov ax,cx mov dx,#0x3c4 out dx,ax inc dx in al,dx and al,al jnz nocirr mov al,bh out dx,al in al,dx cmp al,#0x01 jne nocirr call rst3d4 lea si,dsccirrus lea di,mocirrus br selmod rst3d4: mov dx,#0x3d4 mov al,bl xor ah,ah shl ax,#8 add ax,#0x0c out dx,ax ret nocirr: call rst3d4 ! Check Everex 'clues' mov ax,#0x7000 xor bx,bx int 0x10 cmp al,#0x70 jne noevrx shr dx,#4 cmp dx,#0x678 je istrid cmp dx,#0x236 je istrid lea si,dsceverex lea di,moeverex br selmod istrid: lea cx,ev2tri jmp cx noevrx: lea si,idgenoa ! Check Genoa 'clues' xor ax,ax seg es mov al,[0x37] mov di,ax mov cx,#0x04 dec si dec di l1: inc si inc di mov al,(si) test al,al jz l2 seg es cmp al,(di) l2: loope l1 cmp cx,#0x00 jne nogen lea si,dscgenoa lea di,mogenoa br selmod nogen: cld lea si,idoakvga mov di,#0x08 mov cx,#0x08 repe cmpsb jne nooak lea si,dscoakvga lea di,mooakvga br selmod nooak: cld lea si,idparadise ! Check Paradise 'clues' mov di,#0x7d mov cx,#0x04 repe cmpsb jne nopara lea si,dscparadise lea di,moparadise br selmod nopara: mov dx,#0x3c4 ! Check Trident 'clues' mov al,#0x0e out dx,al inc dx in al,dx xchg ah,al xor al,al out dx,al in al,dx xchg al,ah mov bl,al ! Strange thing ... in the book this wasn't and bl,#0x02 ! necessary but it worked on my card which jz setb2 ! is a trident. Without it the screen goes and al,#0xfd ! blurred ... jmp clrb2 ! setb2: or al,#0x02 ! clrb2: out dx,al and ah,#0x0f cmp ah,#0x02 jne notrid ev2tri: lea si,dsctrident lea di,motrident jmp selmod notrid: mov dx,#0x3cd ! Check Tseng 'clues' in al,dx ! Could things be this simple ! :-) mov bl,al mov al,#0x55 out dx,al in al,dx mov ah,al mov al,bl out dx,al cmp ah,#0x55 jne notsen lea si,dsctseng lea di,motseng jmp selmod notsen: mov dx,#0x3cc ! Check Video7 'clues' in al,dx mov dx,#0x3b4 and al,#0x01 jz even7 mov dx,#0x3d4 even7: mov al,#0x0c out dx,al inc dx in al,dx mov bl,al mov al,#0x55 out dx,al in al,dx dec dx mov al,#0x1f out dx,al inc dx in al,dx mov bh,al dec dx mov al,#0x0c out dx,al inc dx mov al,bl out dx,al mov al,#0x55 xor al,#0xea cmp al,bh jne novid7 lea si,dscvideo7 lea di,movideo7 jmp selmod novid7: lea si,dsunknown lea di,mounknown selmod: xor cx,cx mov cl,(di) mov ax,modesave cmp ax,#ASK_VGA je askmod cmp ax,#NORMAL_VGA je askmod cmp al,cl jl gotmode push si lea si,msg4 call prtstr pop si askmod: push si lea si,msg2 call prtstr pop si push si push cx tbl: pop bx push bx mov al,bl sub al,cl call modepr lodsw xchg al,ah call dprnt xchg ah,al push ax mov al,#0x78 call prnt1 pop ax call dprnt push si lea si,crlf ! print CR+LF call prtstr pop si loop tbl pop cx lea si,msg3 call prtstr pop si add cl,#0x30 jmp nonum nonumb: call beep nonum: call getkey cmp al,#0x30 ! ascii `0' jb nonumb cmp al,#0x3a ! ascii `9' jbe number cmp al,#0x61 ! ascii `a' jb nonumb cmp al,#0x7a ! ascii `z' ja nonumb sub al,#0x27 cmp al,cl jae nonumb sub al,#0x30 jmp gotmode number: cmp al,cl jae nonumb sub al,#0x30 gotmode: xor ah,ah or al,al beq vga50 push ax dec ax beq vga28 add di,ax mov al,(di) int 0x10 pop ax shl ax,#1 add si,ax lodsw pop ds ret ! Routine to print asciiz-string at DS:SI prtstr: lodsb and al,al jz fin call prnt1 jmp prtstr fin: ret ! Routine to print a decimal value on screen, the value to be ! printed is put in al (i.e 0-255). dprnt: push ax push cx xor ah,ah ! Clear ah mov cl,#0x0a idiv cl cmp al,#0x09 jbe lt100 call dprnt jmp skip10 lt100: add al,#0x30 call prnt1 skip10: mov al,ah add al,#0x30 call prnt1 pop cx pop ax ret ! ! Routine to print the mode number key on screen. Mode numbers ! 0-9 print the ascii values `0' to '9', 10-35 are represented by ! the letters `a' to `z'. This routine prints some spaces around the ! mode no. ! modepr: push ax cmp al,#0x0a jb digit ! Here is no check for number > 35 add al,#0x27 digit: add al,#0x30 mov modenr, al push si lea si, modestring call prtstr pop si pop ax ret ! Part of above routine, this one just prints ascii al prnt1: push ax push cx xor bh,bh mov cx,#0x01 mov ah,#0x0e int 0x10 pop cx pop ax ret beep: mov al,#0x07 jmp prnt1 gdt: .word 0,0,0,0 ! dummy .word 0,0,0,0 ! unused .word 0x07FF ! 8Mb - limit=2047 (2048*4096=8Mb) .word 0x0000 ! base address=0 .word 0x9A00 ! code read/exec .word 0x00C0 ! granularity=4096, 386 .word 0x07FF ! 8Mb - limit=2047 (2048*4096=8Mb) .word 0x0000 ! base address=0 .word 0x9200 ! data read/write .word 0x00C0 ! granularity=4096, 386 idt_48: .word 0 ! idt limit=0 .word 0,0 ! idt base=0L gdt_48: .word 0x800 ! gdt limit=2048, 256 GDT entries .word 512+gdt,0x9 ! gdt base = 0X9xxxx msg1: .ascii "Press <RETURN> to see SVGA-modes available, <SPACE> to continue or wait 30 secs." db 0x0d, 0x0a, 0x0a, 0x00 msg2: .ascii "Mode: COLSxROWS:" db 0x0d, 0x0a, 0x0a, 0x00 msg3: db 0x0d, 0x0a .ascii "Choose mode by pressing the corresponding number or letter." crlf: db 0x0d, 0x0a, 0x00 msg4: .ascii "You passed an undefined mode number to setup. Please choose a new mode." db 0x0d, 0x0a, 0x0a, 0x07, 0x00 modestring: .ascii " " modenr: db 0x00 ! mode number .ascii ": " db 0x00 idati: .ascii "761295520" idcandt: .byte 0xa5 idgenoa: .byte 0x77, 0x00, 0x99, 0x66 idparadise: .ascii "VGA=" idoakvga: .ascii "OAK VGA " idf1280: .ascii "Orchid Technology Fahrenheit 1280" id9GXE: .ascii "Graphics Power By" idVRAM: .ascii "Stealth VRAM" ! Manufacturer: Numofmodes+2: Mode: ! Number of modes is the number of chip-specific svga modes plus the extended ! modes available on any vga (currently 2) moati: .byte 0x04, 0x23, 0x33 moahead: .byte 0x07, 0x22, 0x23, 0x24, 0x2f, 0x34 mocandt: .byte 0x04, 0x60, 0x61 mocirrus: .byte 0x06, 0x1f, 0x20, 0x22, 0x31 moeverex: .byte 0x0c, 0x03, 0x04, 0x07, 0x08, 0x0a, 0x0b, 0x16, 0x18, 0x21, 0x40 mogenoa: .byte 0x0c, 0x58, 0x5a, 0x60, 0x61, 0x62, 0x63, 0x64, 0x72, 0x74, 0x78 moparadise: .byte 0x04, 0x55, 0x54 motrident: .byte 0x09, 0x50, 0x51, 0x52, 0x57, 0x58, 0x59, 0x5a motseng: .byte 0x07, 0x26, 0x2a, 0x23, 0x24, 0x22 movideo7: .byte 0x08, 0x40, 0x43, 0x44, 0x41, 0x42, 0x45 mooakvga: .byte 0x08, 0x00, 0x07, 0x4e, 0x4f, 0x50, 0x51 mo9GXE: .byte 0x04, 0x54, 0x55 mof1280: .byte 0x04, 0x54, 0x55 mounknown: .byte 0x02 ! msb = Cols lsb = Rows: ! The first two modes are standard vga modes available on any vga. ! mode 0 is 80x50 and mode 1 is 80x28 dscati: .word 0x5032, 0x501c, 0x8419, 0x842c dscahead: .word 0x5032, 0x501c, 0x842c, 0x8419, 0x841c, 0xa032, 0x5042 dsccandt: .word 0x5032, 0x501c, 0x8419, 0x8432 dsccirrus: .word 0x5032, 0x501c, 0x8419, 0x842c, 0x841e, 0x6425 dsceverex: .word 0x5032, 0x501c, 0x5022, 0x503c, 0x642b, 0x644b, 0x8419, 0x842c, 0x501e, 0x641b, 0xa040, 0x841e dscgenoa: .word 0x5032, 0x501c, 0x5020, 0x642a, 0x8419, 0x841d, 0x8420, 0x842c, 0x843c, 0x503c, 0x5042, 0x644b dscparadise: .word 0x5032, 0x501c, 0x8419, 0x842b dsctrident: .word 0x5032, 0x501c, 0x501e, 0x502b, 0x503c, 0x8419, 0x841e, 0x842b, 0x843c dsctseng: .word 0x5032, 0x501c, 0x503c, 0x6428, 0x8419, 0x841c, 0x842c dscvideo7: .word 0x5032, 0x501c, 0x502b, 0x503c, 0x643c, 0x8419, 0x842c, 0x841c dscoakvga: .word 0x5032, 0x501c, 0x2819, 0x5019, 0x503c, 0x843c, 0x8419, 0x842b dscf1280: .word 0x5032, 0x501c, 0x842b, 0x8419 dsc9GXE: .word 0x5032, 0x501c, 0x842b, 0x8419 dsunknown: .word 0x5032, 0x501c modesave: .word SVGA_MODE .text endtext: .data enddata: .bss endbss: