kolibrios/kernel/trunk/boot/bootcode.inc

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;                                                        ;;
;;  BOOTCODE.INC                                          ;;
;;                                                        ;;
;;  KolibriOS 16-bit loader,                              ;;
;;                        based on bootcode for MenuetOS  ;;
;;                                                        ;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;



;==========================================================================
;
;                           16 BIT FUNCTIONS
;
;==========================================================================

putchar:
; in: al=character
    mov    ah, 0Eh
    mov    bh, 0
    int    10h
    ret

print:
; in: si->string
    mov    al, 186
    call    putchar
    mov    al, ' '
    call    putchar

printplain:
; in: si->string
    pusha
    lodsb
@@:
    call    putchar
    lodsb
    cmp    al, 0
    jnz    @b
    popa
    ret

; Now int 16 is used for keyboard support.
; This is shorter, simpler and more reliable.
if 0
getkey:      push  ecx
             push  edx
             add   ebx,0x0101
             xor   eax,eax

           gk1:
             in    al,0x60
             mov   cl,al
           gk0:
             in    al,0x60
             cmp   al,cl
             je    gk0
             cmp   ax,11
             jg    gk0
             gk0_1:
             mov   cl,al

;             add   al,47
;             mov   [ds:keyinbs-0x10000],al
;             mov   si,keyinbs-0x10000
;             call  printplain

           gk12:
             in    al,0x60
             cmp   al,cl
             je    gk12
             cmp   ax,240
             jne   gk13
             mov   al,cl
             jmp   gk14
           gk13:
             add   cl,128
             cmp   al,cl
             jne   gk1
             sub   al,128
           gk14:

             movzx edx,bl
             cmp   eax,edx
             jb    gk1
             movzx edx,bh
             cmp   eax,edx
             jg    gk1
             test  ebx,0x010000
             jnz   gk3
             mov   cx,0x1000
             mov   dx,cx
             add   eax,47
             mov   cx,ax
             cmp   cx,58
             jb    gk_nozero
             sub   cx,10
           gk_nozero:
             mov   [ds:keyin-0x10000],cl
             mov   si,keyin-0x10000
             call  printplain
           gk3:
             sub   eax,48
             pop   edx
             pop   ecx
             ret
end if

getkey:
; get number in range [bl,bh] (bl,bh in ['0'..'9'])
; in: bx=range
; out: ax=digit (1..9, 10 for 0)
    mov    ah, 0
    int    16h
    cmp    al, bl
    jb    getkey
    cmp    al, bh
    ja    getkey
    push    ax
    call    putchar
    pop    ax
    and    ax, 0Fh
    jnz    @f
    mov    al, 10
@@:
    ret

setcursor:
; in: dl=column, dh=row
    mov    ah, 2
    mov    bh, 0
    int    10h
    ret

macro _setcursor row,column
{
    mov    dx, row*256 + column
    call    setcursor
}

pagetable_set:
;eax - physical address
;es:di - page table
;ecx - number of pages to map
    or    al, 7
@@:
    stosd
    add    eax, 1000h
    loop    @b
    ret

boot_read_floppy:
        push    si
        xor     si, si
        mov     ah, 2   ; read
@@:
        push    ax
        int     0x13
        pop     ax
        jnc     @f
        inc     si
        cmp     si, 10
        jb      @b
        mov     si, badsect-0x10000
sayerr_plain:
        call    printplain
        jmp     $
@@:
        pop     si
        ret

; 16-bit data
; videomodes table
		org $+0x10000
gr_table:
    dw      0x112+0100000000000000b ,  640 ,  480        ; 1
    dw      0x115+0100000000000000b ,  800 ,  600        ; 2
    dw      0x118+0100000000000000b , 1024 ,  768        ; 3
    dw      0x11B+0100000000000000b , 1280 , 1024        ; 4
    dw      0x112 ,  640 , 480                ; 5
    dw      0x115 ,  800 , 600                ; 6
    dw      0x118 , 1024 , 768                ; 7
    dw      0x11B , 1280 ,1024                ; 8
    dw    0x13, 640, 480                    ; 9
    dw    0x12, 640, 480                    ; 0

; table for move to extended memory (int 15h, ah=87h)
       movedesc:
        db      0x00,0x00,0x0,0x00,0x00,0x00,0x0,0x0
        db      0x00,0x00,0x0,0x00,0x00,0x00,0x0,0x0

        db      0xff,0xff,0x0,0xa0,0x00,0x93,0x0,0x0
        db      0xff,0xff,0x0,0x00,0x10,0x93,0x0,0x0

        db      0x00,0x00,0x0,0x00,0x00,0x00,0x0,0x0
        db      0x00,0x00,0x0,0x00,0x00,0x00,0x0,0x0
        db      0x00,0x00,0x0,0x00,0x00,0x00,0x0,0x0
        db      0x00,0x00,0x0,0x00,0x00,0x00,0x0,0x0
        	org $-0x10000

;=========================================================================
;
;                           16 BIT CODE
;
;=========================================================================


start_of_code:
    cld
; \begin{diamond}[02.12.2005]
    cmp    ax, 'KL'
    jnz    @f
    mov    word [cs:cfgmanager.loader_block-0x10000], si
    mov    word [cs:cfgmanager.loader_block+2-0x10000], ds
@@:
; \end{diamond}[02.12.2005]

; set up stack
    mov    ax, 3000h
    mov    ss, ax
    mov    sp, 0EC00h
; set up segment registers
    push    cs
    pop    ds
    push    cs
    pop    es

; set videomode
    mov    ax, 3
        int  0x10

if lang eq ru
 ; Load & set russian VGA font (RU.INC)
        mov  bp,RU_FNT1-10000h   ; RU_FNT1 - First part
          mov  bx,1000h            ; 768 bytes
          mov  cx,30h              ; 48 symbols
          mov  dx,80h              ; 128 - position of first symbol
        mov  ax,1100h
          int  10h

        mov  bp,RU_FNT2-10000h   ; RU_FNT2 -Second part
        mov  bx,1000h            ; 512 bytes
        mov  cx,20h              ; 32 symbols
        mov  dx,0E0h             ; 224 - position of first symbol
        mov  ax,1100h
          int  10h
 ; End set VGA russian font
end if

; draw frames
    push    0xb800
    pop    es
    xor    di, di
;        mov  si,d80x25-0x10000
;        mov  cx,80*25
;        mov  ah,1*16+15
;       dfl1:
;        lodsb
;        stosw
;        loop dfl1
    mov    ah, 1*16+15
; draw top
    mov    si, d80x25_top - 0x10000
    mov    cx, d80x25_top_num * 80
@@:
    lodsb
    stosw
    loop    @b
; draw spaces
    mov    si, space_msg - 0x10000
    mov    cx, 25 - d80x25_top_num - d80x25_bottom_num
dfl1:
    push    cx
    push    si
    mov    cx, 80
@@:
    lodsb
    stosw
    loop    @b
    pop    si
    pop    cx
    loop    dfl1
; draw bottom
    mov    si, d80x25_bottom - 0x10000
    mov    cx, d80x25_bottom_num * 80
@@:
    lodsb
    stosw
    loop    @b

    mov    byte [space_msg-0x10000+80], 0    ; now space_msg is null terminated

    _setcursor d80x25_top_num,0


; TEST FOR 386+

    mov    bx, 0x4000
        pushf
        pop     ax
        mov     dx,ax
        xor     ax,bx
        push    ax
        popf
        pushf
        pop     ax
        and     ax,bx
        and     dx,bx
        cmp     ax,dx
        jnz     cpugood
        mov     si,not386-0x10000
sayerr:
        call    print
        jmp     $
     cpugood:

; set up esp
    movzx    esp, sp

; FLUSH 8042 KEYBOARD CONTROLLER

;// mike.dld [
 ;       mov     al,0xED
 ;       out     0x60,al
 ;       or      cx,-1
 ;     @@:
 ;       in      al,0x64
 ;       test    al,2
 ;       jz      @f
 ;       loop    @b
 ;     @@:
 ;       mov     al,0
 ;       out     0x60,al
 ;       or      cx,-1
 ;     @@:
 ;       in      al,0x64
 ;       test    al,2
 ;       jz      @f
 ;       loop    @b
 ;     @@:
;// mike.dld ]

;       mov     ecx,10000
;      fl1:
;       in      al,0x64
;       loop    fl1
;       test    al,1
;       jz      fl2
;       in      al,0x60
;       jmp     fl1
;      fl2:

;****************************************************************
; The function is modified Mario79
;*****************************************************************
; wait_kbd:        ; variant 1
;       mov      cx,2500h  ;<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> 10 <EFBFBD><EFBFBD><EFBFBD><EFBFBD>
; test_kbd:
;       in       al,64h    ;<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
;       test     al,2      ;<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <EFBFBD><EFBFBD><EFBFBD><EFBFBD> <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
;       loopnz   test_kbd

    mov   al,0xf6         ; <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>, <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
    out   0x60,al
    xor   cx,cx
wait_loop:       ; variant 2
; reading state of port of 8042 controller
        in      al,64h 
        and     al,00000010b  ; ready flag
; wait until 8042 controller is ready 
        loopnz  wait_loop

; --------------- APM ---------------------
    push    0
    pop    es
    mov    word [es : 0x9044], 0        ; ver = 0.0 (APM not found)
    mov    ax, 0x5300
    xor    bx, bx
    int    0x15
    jc    apm_end                ; APM not found
    test    cx, 2
    jz    apm_end                ; APM 32-bit protected-mode interface not supported
    mov    [es : 0x9044], ax        ; Save APM Version
    mov    [es : 0x9046], cx        ; Save APM flags
    
    ; Write APM ver ----
    and    ax, 0xf0f
    add    ax, '00'
    mov    si, msg_apm - 0x10000
    mov    [si + 5], ah
    mov    [si + 7], al
    _setcursor 0, 3
    call    printplain
    _setcursor d80x25_top_num,0
    ; ------------------
    
    mov    ax, 0x5304            ; Disconnect interface
    xor    bx, bx
    int    0x15
    mov    ax, 0x5303            ; Connect 32 bit mode interface
    xor    bx, bx
    int    0x15
    ; init selectors
    movzx    eax, ax ; real-mode segment base address of protected-mode 32-bit code segment
    shl    eax, 4
    mov    [apm_code_32 - 0x10000 + 2], ax
    shr    eax, 16
    mov    [apm_code_32 - 0x10000 + 4], al
    movzx    ecx, cx ; real-mode segment base address of protected-mode 16-bit code segment
    shl    ecx, 4
    mov    [apm_code_16 - 0x10000 + 2], cx
    shr    ecx, 16
    mov    [apm_code_16 - 0x10000 + 4], cl
    movzx    edx, dx ; real-mode segment base address of protected-mode 16-bit data segment
    shl    edx, 4
    mov    [apm_data_16 - 0x10000 + 2], dx
    shr    edx, 16
    mov    [apm_data_16 - 0x10000 + 4], dl
    mov    [es : 0x9040], ebx              ; offset of APM entry point
apm_end:
; -----------------------------------------        

; DISPLAY VESA INFORMATION

    push    0
    pop    es
        mov     ax,0x4f00
        mov     di,0xa000
        int     0x10
        cmp     ax,0x004f
        mov    si, novesa-0x10000
        jnz    @f
        mov     ax,[es:di+4]
        add     ax,'0'*256+'0'
        mov    si,vervesa-0x10000
        mov     [si+vervesa_off], ah
        mov     [si+vervesa_off+2], al
@@:     call    print

; \begin{diamond}[30.11.2005]
cfgmanager:
; settings:
; a) preboot_graph = graphical mode
;    preboot_gprobe = probe this mode?
; b) preboot_mtrr = use hardware acceleration?
; c) preboot_vrrm = use VRR?
; d) preboot_device = from what boot?
    mov    di, preboot_graph-0x10000
; check bootloader block
    cmp    [.loader_block-0x10000], 1
    jnz    .noloaderblock
    les    bx, [.loader_block-0x10000]
    cmp    byte [es:bx], 1
    mov    si, loader_block_error-0x10000
    jnz    sayerr
    test    byte [es:bx+1], 1
    jz    @f
; image in memory present
    cmp    [di+preboot_device-preboot_graph], 0
    jnz    @f
    mov    [di+preboot_device-preboot_graph], 3
@@:
.noloaderblock:
; determine default settings
    mov    [.bSettingsChanged-0x10000], 0
    cmp    byte [di], 0
    jnz    .preboot_gr_end
    mov    [di+preboot_gprobe-preboot_graph], 0
    mov    al, [vervesa+vervesa_off-0x10000]
    cmp    al, 'x'
    jz    .novesa
    cmp    al, '1'
    jz    .vesa12
    mov    [di+preboot_gprobe-preboot_graph], 2
    mov    al, 3
    jmp    @f
.vesa12:
    mov    al, 7
    jmp    @f
.novesa:
    mov    al, 10
@@:
    mov    [di], al
.preboot_gr_end:
    cmp    [di+preboot_mtrr-preboot_graph], 1
    adc    [di+preboot_mtrr-preboot_graph], 0
    cmp    [di+preboot_vrrm-preboot_graph], 1
    adc    [di+preboot_vrrm-preboot_graph], 0
    cmp    [di+preboot_device-preboot_graph], 1
    adc    [di+preboot_device-preboot_graph], 0
; notify user
    mov    si, linef-0x10000
    call    print
    mov    si, start_msg-0x10000
    call    print
    mov    si, time_msg-0x10000
    call    print
; get start time
    call    .gettime
    mov    [.starttime-0x10000], eax
    mov    word [.timer-0x10000], .newtimer
    mov    word [.timer-0x10000+2], cs
.printcfg:
    _setcursor 9,0
    mov    si, current_cfg_msg-0x10000
    call    print
    mov    si, curvideo_msg-0x10000
    call    print
    mov    al, [preboot_graph-0x10000]
    cmp    al, 8
    ja    .pnovesa
    mov    dl, al
    and    eax, 3
    mov    si, [modes_msg-0x10000+eax*2]
    call    printplain
    mov    si, modevesa20-0x10000
    cmp    dl, 4
    jbe    @f
    mov    si, modevesa12-0x10000
@@:
    call    printplain
    cmp    dl, 4
    ja    .x
    mov    si, probeno_msg-0x10000
    cmp    [preboot_gprobe-0x10000], 2
    jnz    @f
    mov    si, probeok_msg-0x10000
@@:
    call    printplain
.x:
    jmp    .c
.pnovesa:
    cmp    al, 9
    mov    si, mode9-0x10000
    jz    @b
    mov    si, mode10-0x10000
    jmp    @b
.c:
    mov    si, linef-0x10000
    call    printplain
    mov    si, mtrr_msg-0x10000
    cmp    [preboot_mtrr-0x10000], 1
    call    .say_on_off
    mov    si, vrrm_msg-0x10000
    cmp    [preboot_vrrm-0x10000], 1
    call    .say_on_off
    mov    si, preboot_device_msg-0x10000
    call    print
    mov    al, [preboot_device-0x10000]
    and    eax, 3
    mov    si, [preboot_device_msgs-0x10000+eax*2]
    call    printplain
.wait:
    _setcursor 25,0        ; out of screen
; set timer interrupt handler
    cli
    push    0
    pop    es
    mov    eax, [es:8*4]
    mov    [.oldtimer-0x10000], eax
    mov    eax, [.timer-0x10000]
    mov    [es:8*4], eax
    sti
; wait for keypressed
    mov    ah, 0
    int    16h
    push    ax
; restore timer interrupt
    push    0
    pop    es
    mov    eax, [.oldtimer-0x10000]
    mov    [es:8*4], eax
    mov    [.timer-0x10000], eax
    _setcursor 7,0
    mov    si, space_msg-0x10000
    call    printplain
    pop    ax
; switch on key
    cmp    al, 13
    jz    .continue
    or    al, 20h
    cmp    al, 'a'
    jz    .change_a
    cmp    al, 'b'
    jz    .change_b
    cmp    al, 'c'
    jz    .change_c
    cmp    al, 'd'
    jnz    .wait
    _setcursor 15,0
    mov     si,bdev-0x10000
    call    print
    mov     bx,'13'
    call    getkey
    mov    [preboot_device-0x10000], al
    _setcursor 13,0
.d:
    mov    [.bSettingsChanged-0x10000], 1
    mov    si, space_msg-0x10000
    call    printplain
    _setcursor 15,0
    mov    cx, 6
@@:
    call    printplain
    loop    @b
    jmp    .printcfg
.change_a:
    _setcursor 15,0
    mov    si, gr_mode-0x10000
    call    printplain
    mov     bx, '09'
    call    getkey
    mov    [preboot_graph-0x10000], al
    cmp    al, 4
    ja    @f
    mov    si, probetext-0x10000
    call    printplain
    mov    bx, '12'
    call    getkey
    mov    [preboot_gprobe-0x10000], al
@@:
    _setcursor 10,0
    jmp    .d
.change_b:
    _setcursor 15,0
    mov    si, gr_acc-0x10000
    call    print
    mov    bx, '12'
    call    getkey
    mov    [preboot_mtrr-0x10000], al
    _setcursor 11,0
    jmp    .d
.change_c:
    _setcursor 15,0
    mov    si, vrrmprint-0x10000
    call    print
    mov    bx, '12'
    call    getkey
    mov    [preboot_vrrm-0x10000], al
    _setcursor 12,0
    jmp    .d
.say_on_off:
    pushf
    call    print
    mov    si, on_msg-0x10000
    popf
    jz    @f
    mov    si, off_msg-0x10000
@@:    call    printplain
    ret
; novesa and vervesa strings are not used at the moment of executing this code
virtual at novesa
.oldtimer dd ?
.starttime dd ?
.bSettingsChanged db ?
.timer dd ?
end virtual
	org $+0x10000
.loader_block dd 0
	org $-0x10000
.gettime:
    mov    ah, 0
    int    1Ah
    xchg    ax, cx
    shl    eax, 10h
    xchg    ax, dx
    ret
.newtimer:
    push    ds
    push    cs
    pop    ds
    pushf
    call    [.oldtimer-0x10000]
    pushad
    call    .gettime
    sub    eax, [.starttime-0x10000]
    sub    ax, 18*5
    jae    .timergo
    neg    ax
    add    ax, 18-1
    mov    bx, 18
    xor    dx, dx
    div    bx
if lang eq ru
; <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> 5 ᥪ㭤, 4/3/2 ᥪ㭤<EFBFBD>, 1 ᥪ㭤<EFBFBD>
    cmp    al, 5
    mov    cl, ' '
    jae    @f
    cmp    al, 1
    mov    cl, '<27>'
    jz    @f
    mov    cl, '<27>'
@@:    mov    [time_str+9-0x10000], cl
else
; wait 5/4/3/2 seconds, 1 second
    cmp    al, 1
    mov    cl, 's'
    ja    @f
    mov    cl, ' '
@@:    mov    [time_str+9-0x10000], cl
end if
    add    al, '0'
    mov    [time_str+1-0x10000], al
    mov    si, time_msg-0x10000
    _setcursor 7,0
    call    print
    _setcursor 25,0
    popad
    pop    ds
    iret
.timergo:
    push    0
    pop    es
    mov    eax, [.oldtimer-0x10000]
    mov    [es:8*4], eax
    mov    sp, 0EC00h
.continue:
    sti
    _setcursor 6,0
    mov    si, space_msg-0x10000
    call    printplain
    call    printplain
    _setcursor 6,0
    mov    si, loading_msg-0x10000
    call    print
    _setcursor 15,0
    cmp    [.bSettingsChanged-0x10000], 0
    jz    .load
    cmp    [.loader_block-0x10000], 0
    jz    .load
    les    bx, [.loader_block-0x10000]
    mov    eax, [es:bx+3]
    push    ds
    pop    es
    test    eax, eax
    jz    .load
    push    eax
    mov    si, save_quest-0x10000
    call    print
.waityn:
    mov    ah, 0
    int    16h
    or    al, 20h
    cmp    al, 'n'
    jz    .loadc
    cmp    al, 'y'
    jnz    .waityn
    call    putchar
    mov    byte [space_msg-0x10000+80], 186
    pop    eax
    push    cs
    push    .cont
    push    eax
    retf
.loadc:
    pop    eax
.cont:
    push    cs
    pop    ds
    mov    si, space_msg-0x10000
    mov    byte [si+80], 0
    _setcursor 15,0
    call    printplain
    _setcursor 15,0
.load:
; \end{diamond}[02.12.2005]

; ASK GRAPHICS MODE

    movzx    ax, [preboot_graph-0x10000]
    push    0
    pop    es
; address is gr_table+6*(ax-1)-0x10000
        add    ax, ax
        lea    si, [gr_table-0x10000 + eax + eax*2 - 6]
        mov     bx,[si+0]
        mov     cx,[si+2]
        mov     dx,[si+4]
        cmp    al, 9*2
        mov    al, 32    ; BPP
        jb    @f
        mov    [es:0x9000], al
        mov    dword [es:0x9018], 0x800000
       @@:
        mov     [es:0x9008],bx
        mov     [es:0x900A],cx
        mov     [es:0x900C],dx
        test    bh, bh
        jz    nov

; USE DEFAULTS OR PROBE

; bx - mode : cx - x size : dx - y size
    cmp    [preboot_gprobe-0x10000], 1
    jz    noprobe

        mov     bx,0x100
     newprobe:
        inc     bx
        cmp     bx,0x17f
        mov    si,prnotfnd-0x10000
        jz    sayerr

     probemore:
         push    cx
        mov     ax,0x4f01
        mov     cx,bx
        and     cx,0xfff
        mov     di,0xa000
        int     0x10
        pop    cx

    test    byte [es:di], 80h    ; lfb?
    jz    newprobe
    cmp    [es:di+0x12], cx    ; x size?
    jnz    newprobe
    cmp    [es:di+0x14], dx    ; y size?
    jnz    newprobe
    cmp    byte [es:di+0x19], 32 ;24
    jb    newprobe

;       add     bx,0100000000000000b
    or    bh, 40h
        mov     [es:0x9008],bx

     noprobe:


; FIND VESA 2.0 LFB & BPP

        mov     ax,0x4f01
        mov     cx,bx
        and     cx,0xfff
        mov     di,0xa000
        int     0x10
        ; LFB
        mov     eax,[es:di+0x28]
        mov     [es:0x9018],eax
        ; ---- vbe voodoo
        BytesPerScanLine equ 0x10
        mov ax, [es:di+BytesPerScanLine]
        mov [es:0x9001],ax
        ; BPP
        mov     al,byte [es:di+0x19]
        mov     [es:0x9000],al
       nov:
        cmp     al,24
        mov    si,bt24-0x10000
        jz    bppl
        cmp     al,32
        mov     si,bt32-0x10000
        jz     bppl
        mov     si,btns-0x10000
        jmp    sayerr
       bppl:
        call    print


; FIND VESA 1.2 PM BANK SWITCH ADDRESS

    push    es
        mov     ax,0x4f0A
        xor    bx, bx
        int     0x10
        xor     eax,eax
        mov     ax,es
        shl     eax,4
        movzx   ebx,di
        add     eax,ebx
        mov     bx,[es:di]
        add     eax,ebx
        pop     es
        mov     [es:0x9014],eax


; GRAPHICS ACCELERATION

        mov     al, [preboot_mtrr-0x10000]
        mov     [es:0x901C],al

; VRR_M USE

        mov     al,[preboot_vrrm-0x10000]
        mov     [es:0x9030],al


; MEMORY MODEL

;        movzx   eax,byte [es:preboot_memory-0x10000]
;        cmp     eax,0
;        jne     pre_mem
;;;;;;;;;;;;;;;;;;;;;;;;;
; mario79 - memory size ;
;;;;;;;;;;;;;;;;;;;;;;;;;
;           mov ax,0E801h
;;;           xor bx,bx    ; thanks to Alexei for bugfix [18.07.2004]
;           xor cx, cx
;           xor dx, dx
;           int 0x15
;           movzx ebx, dx ;bx
;           movzx eax, cx ;ax
;           shl   ebx,6   ; <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <EFBFBD> <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> (x64)
;           add   eax,ebx
;           add eax, 1000h ;440h
;           cmp eax,40000h ; 256?
;           jge mem_256_z
;           cmp eax,20000h ; 128?
;           jge mem_128_z
;           cmp eax,10000h ; 64?
;           jge mem_64_z
;           cmp eax,8000h ; 32?
;           jge mem_32_z
;           jmp mem_16_z
;
;mem_256_z: mov     si,memokz256-0x10000
;           call    printplain
;           mov eax,5
;           jmp pre_mem
;mem_128_z: mov     si,memokz128-0x10000
;           call    printplain
;           mov eax,4
;           jmp pre_mem
;mem_64_z:  mov     si,memokz64-0x10000
;           call    printplain
;           mov eax,3
;           jmp pre_mem
;mem_32_z:  mov     si,memokz32-0x10000
;           call    printplain
;           mov eax,2
;           jmp pre_mem
;mem_16_z:  mov     si,memokz16-0x10000
;           call    printplain
;           mov eax,1
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;      pre_mem:
;        push    word 0x0000
;        pop     es
;        mov     [es:0x9030],al
;        push    word 0x1000
;        pop     es
;        mov     si,linef-0x10000
;        call    printplain




; DIRECT WRITE TO LFB, PAGING DISABLED

;        movzx   eax,byte [es:preboot_lfb-0x10000]
;        mov     eax,1                             ; paging disabled
;        cmp     eax,0
;        jne     pre_lfb
;        mov     si,gr_direct-0x10000
;        call    printplain
;        mov     ebx,'12'
;        call    getkey
;      pre_lfb:
;        push    word 0x0000
;        pop     es
;        mov     [es:0x901E],al
;        mov     ax,0x1000
;        mov     es,ax
;        mov     si,linef-0x10000
;        call    printplain
        mov     [es:0x901E],byte 1



; BOOT DEVICE

    mov    al, [preboot_device-0x10000]
        dec     al
        mov     [boot_dev-0x10000],al

; READ DISKETTE TO MEMORY

;        cmp     [boot_dev-0x10000],0
        jne     no_sys_on_floppy
        mov     si,diskload-0x10000
        call    print
        xor    ax, ax            ; reset drive
        xor    dx, dx
        int     0x13
; now load floppy image to memory
; at first load boot sector and first FAT table
        mov     cx, 0x0001      ; startcyl,startsector
        xor     dx, dx          ; starthead,drive
        mov     al, 1+9         ; no of sectors to read
        mov     bx, 0xB000      ; es:bx -> data area
        call    boot_read_floppy
; and copy them to extended memory
        mov     si, movedesc-0x10000
        mov     [si+8*2+3], bh
        push    es
        push    ds
        pop     es
        mov     cx, 256*10
        mov     ah, 0x87
        int     0x15
        test    ah, ah
        jz      @f
sayerr_floppy:
        mov     dx, 0x3f2
        mov     al, 0
        out     dx, al
        mov     si, memmovefailed-0x10000
        jmp     sayerr_plain
@@:
        add     dword [si+8*3+2], 512*10
; copy FAT to second copy
        mov     byte [si+8*2+3], 0xB2
        mov     cx, 256*9
        mov     ah, 0x87
        int     0x15
        pop     es
        test    ah, ah
        jnz     sayerr_floppy
        add     dword [si+8*3+2], 512*9
; calculate total number of sectors to read
        mov     ax, 1+9+14      ; boot+FAT+root
        mov     di, 0xB203
.calc_loop:
        test    word [es:di], 0xFFF
        jz      @f
        inc     ax
@@:
        test    word [es:di+1], 0xFFF0
        jz      @f
        inc     ax
@@:
        add     di, 3
        cmp     di, 0xB200+1440*3
        jb      .calc_loop
        push    ax
        mov     bp, 1+9         ; already read sectors
; now read rest
        mov     byte [si+8*2+3], 0xA0
        mov     di, 2-14        ; absolute sector-31
        mov     cx, 0x0002      ; cylinder=0, sector=2
        mov     dx, 0x0100      ; head=1, disk=0
.read_loop:
; determine whether sector must be read
        cmp     di, 2
        jl      .read
        mov     bx, di
        shr     bx, 1
        jnc     .even
        test    word [es:bx+di+0xB200], 0xFFF0
        jmp     @f
.even:
        test    word [es:bx+di+0xB200], 0xFFF
@@:
        jz      .skip
.read:
        mov     bx, 0xA000
        mov     al, 1           ; 1 sector
        call    boot_read_floppy
        inc     bp
        push    es
        push    ds
        pop     es
        pusha
        mov     cx, 256
        mov     ah, 0x87
        int     0x15
        test    ah, ah
        popa
        pop     es
        jnz     sayerr_floppy
.skip:
        add     dword [si+8*3+2], 512
        inc     cx
        cmp     cl, 19
        jnz     @f
        mov     cl, 1
        inc     dh
        cmp     dh, 2
        jnz     @f
        mov     dh, 0
        inc     ch
@@:
        pop     ax
        push    ax
        pusha
; draw percentage
; total sectors: ax
; read sectors: bp
        xchg    ax, bp
        mov     cx, 100
        mul     cx
        div     bp
        aam
        xchg    al, ah
        add     ax, '00'
        mov     si, pros-0x10000
        cmp     [si], ax
        jz      @f
        mov     [si], ax
        call    printplain
@@:
        popa
        inc     di
        cmp     di, 2880-31
        jnz     .read_loop

;        mov     cx, 0x0001      ; startcyl,startsector
;        xor     dx, dx          ; starthead,drive
;        push    word 80*2               ; read no of sect
;       reads:
;        pusha
;        xor     si,si
;       newread:
;        mov     bx,0xa000               ; es:bx -> data area
;        mov     ax,0x0200+18            ; read, no of sectors to read
;        int     0x13
;        test    ah, ah
;        jz      goodread
;        inc    si
;        cmp     si,10
;        jnz     newread
;        mov     si,badsect-0x10000
;sayerr_plain:
;        call    printplain
;        jmp     $
;       goodread:
;        ; move -> 1mb
;        mov     si,movedesc-0x10000
;        push    es
;        push    ds
;        pop     es
;        mov     cx,256*18
;        mov     ah,0x87
;        int     0x15
;        pop    es
;
;        test    ah,ah                  ; was the move successfull ?
;        je      goodmove
;        mov     dx,0x3f2              ; floppy motor off
;        mov     al,0
;        out     dx,al
;        mov     si,memmovefailed-0x10000
;        jmp    sayerr_plain
;      goodmove:
;
;    add    dword [movedesc-0x10000+0x18+2], 512*18
;        popa
;        inc     dh
;        cmp     dh,2
;        jnz     bb2
;        mov     dh,0
;        inc     ch
;        pusha                        ; print prosentage
;        mov     si,pros-0x10000
;    shr    ch, 2
;    mov    al, '5'
;    test    ch, 1
;    jnz    @f
;    mov    al, '0'
;@@:
;    mov    [si+1], al
;    shr    ch, 1
;    add    ch, '0'
;    mov    [si], ch
;        call    printplain
;        popa
;       bb2:
;        pop     ax
;        dec     ax
;        push    ax
;        jnz     reads
;       readdone:
;        pop     ax
        mov     si,backspace2-0x10000
        call    printplain
        mov     si,okt-0x10000
        call    printplain
       no_sys_on_floppy:
        xor    ax, ax        ; reset drive
        xor    dx, dx
        int     0x13
       mov dx,0x3f2 ; floppy motor off
       mov al,0
       out dx,al

    push    es
; PAGE TABLE

    push    dword [es:0x9018]

        map_mem equ 64                ; amount of memory to map

        push    0x6000
        pop    es                    ; es:di = 6000:0
        xor     di,di
        mov     cx,256*map_mem         ; Map (mapmem) M
; initialize as identity mapping
    xor    eax, eax
    call    pagetable_set

        
; 4 KB PAGE DIRECTORY

    push    0x7F00
    pop    es                ; es:di = 7F00:0
        xor     di, di
        mov     cx, 64 / 4
        mov     eax, 0x60007            ; for 0 M
        call    pagetable_set
        xor     si,si
        mov     di,second_base_address shr 20
        mov     cx,64/2
        rep     movs word [es:di], [es:si]
       
        mov     eax, 0x7F000 +8+16      ; Page directory and enable caches
        mov     cr3, eax

; SET GRAPHICS

    pop    es
        mov     ax,[es:0x9008]        ; vga & 320x200
        mov    bx, ax
        cmp     ax,0x13
        je      setgr
        cmp     ax,0x12
        je      setgr
        mov     ax,0x4f02            ; Vesa
       setgr:
        int     0x10
        test    ah,ah
        mov    si, fatalsel-0x10000
        jnz    sayerr
; set mode 0x12 graphics registers:
        cmp     bx,0x12
        jne     gmok2

        mov     al,0x05
        mov     dx,0x03ce
        push    dx
        out     dx,al      ; select GDC mode register
        mov     al,0x02
        inc    dx
        out     dx,al      ; set write mode 2

        mov     al,0x02
        mov     dx,0x03c4
        out     dx,al      ; select VGA sequencer map mask register
        mov     al,0x0f
        inc    dx
        out     dx,al      ; set mask for all planes 0-3

        mov     al,0x08
        pop    dx
        out     dx,al      ; select GDC bit mask register
                           ; for writes to 0x03cf

       gmok2:
        push    ds
        pop    es