PC Graphics Unleashed/PC Graphics Unleashed.iso/ch01/vesa_s3.asm

Assembly Source File | 1993-12-06 | 15KB | 505 lines

;--------------------------------------------------------------------------
; This is file VESA_S3.ASM
;
; Copyright (C) 1991 DJ Delorie, 24 Kirsten Ave, Rochester NH 03867-2954
; Copyright (C) 1992 Csaba Biegl, 820 Stirrup Dr, Nashville, TN 37221
; Copyright (C) 1992 Shayne Hughes, UC Davis, CA 95616
;
; This file is distributed under the terms listed in the document
; "copying.dj", available from DJ Delorie at the address above.
; A copy of "copying.dj" should accompany this file; if not, a copy
; should be available from where this file was obtained.  This file
; may not be distributed without a verbatim copy of "copying.dj".
;
; This file is distributed WITHOUT ANY WARRANTY; without even the implied
; warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
;--------------------------------------------------------------------------

; NOTE: this file was formerly called STEALTH.ASM
; It seems that for once the industry is succeeding in manufacturing
; compatible graphics boards, as this driver, orginally written for a
; Diamond Stealth board seems to work unchanged on Orchid F1280 and
; similar S3 based boards, AND EVEN local bus S3 boards.
; Thanks to Shayne Hughes, we now have a paging routine for this
; driver. This allows direct memory access to the video RAM - although
; GRX is not using it.

_TEXT    segment byte public 'CODE'
_TEXT    ends
DGROUP  group    _TEXT,_DATA,_BSS
    assume  cs:_TEXT,ds:DGROUP
_DATA    segment word public 'DATA'
d@    label    byte
d@w    label    word
_DATA    ends
_BSS    segment word public 'BSS'
b@    label    byte
b@w    label    word
_BSS    ends
_TEXT    segment byte public 'CODE'
    assume  cs:_TEXT,ds:DGROUP

include grdriver.inc

;--------------------------------------------------------------------------
; DRIVER HEADER
;  The following entries MUST match the structure and constant
;  declarations in the file 'grdriver.h' of the GRX graphics library
;  The mode word should contain the following bitfields:
;     - the GRD_NEW_DRIVER bit set for any new format driver
;     - the adapter type field should be specified
;     - the memory size field should be specified
;     - the paging mode field should be specified
;  The mode set routine will OR in the plane bitfield as it will
;  change when different color number modes are requested.
;--------------------------------------------------------------------------

    dw    offset mode_set_routine
    dw    offset paging_routine
mode_W  dw    GRD_NEW_DRIVER+GRD_VGA+GRD_1024K+GRD_NO_RW
;
; The 'def_xx' fields are filled in by go32 from the corresponding
; fields of the 'GO32' environment variable
;
def_tw  dw    80        ; text width
def_th  dw    25        ; text height
def_gw  dw    320        ; graphics width
def_gh  dw    200        ; graphics height
def_nc  dw    16        ; graphics colors
    dw    offset driver_init_routine
    dw    offset text_mode_table
    dw    offset graphics_mode_table

;
; Biggest text and graphics sizes
;
Max_TW  equ    80
Max_TH  equ    50
Max_GWn equ    640        ; non interlaced!!!
Max_GHn equ    480
Max_GW  equ    640        ; may be interlaced
Max_GH  equ    480


;--------------------------------------------------------------------------
; TABLE OF SUPPORTED TEXT MODES
;    - keep sorted by size
;    - end with an all 0 entry
;    - BIOS field = 0xff disables it
;    - fields:
;        width,  height, colors, BIOS#+  setup_procedure_index*256
;--------------------------------------------------------------------------
text_mode_table        label word
    dw    80,    25,    2,    007h +  00000h
    dw    40,    25,    16,    001h +  00000h
    dw    80,    25,    16,    003h +  00000h
    dw    80,    28,    16,    003h +  00400h  ; 80x25 + reload 14 row font
    dw    80,    50,    16,    003h +  00600h  ; 80x25 + reload 8 row font
    dw    132,    25,    16,    109h +  00000h  ; VESA 109h mode
    dw    132,    28,    16,    109h +  00400h  ; VESA 109h mode (132x25) + reload 14 row font
    dw    132,    44,    16,    10ah +  00000h  ; VESA 10ah mode
    dw    132,    50,    16,    109h +  00600h  ; VESA 109h mode (132x25) + reload 8 row font
    dw    0,    0,    0,    000h +  00000h

;--------------------------------------------------------------------------
; TABLE OF SUPPORTED GRAPHICS MODES
;    - keep sorted first by colors then by size
;    - end with an all 0 entry
;    - BIOS field = 0xff disables it
;    - fields:
;        width,  height, colors, BIOS#+  setup_procedure_index*256
;--------------------------------------------------------------------------
graphics_mode_table    label word
    dw    320,    200,    16,    00dh +  00000h
    dw    640,    200,    16,    00eh +  00000h
    dw    640,    350,    16,    010h +  00000h
    dw    640,    480,    16,    012h +  00000h
    dw    800,    600,    16,    002h +  00100h  ; VESA 102h mode
    dw    320,    200,    256,    013h +  00000h
    dw    640,    480,    256,    001h +  00200h  ; VESA S3 201h mode
    dw    800,    600,    256,    003h +  00200h  ; VESA S3 203h mode
    dw     1024,    768,    256,    005h +  00200h  ; VESA S3 205h mode
    dw    0,    0,    0,    000h +  00000h

;--------------------------------------------------------------------------
; TABLE OF SPECIAL SETUP PROCEDURES
;  You may need such procedures for:
;     -- reloading fonts on standard EGA or VGA for
;     higher resolution text modes
;     -- enable HiColor mode of some Super VGAs
;     -- Handle the parameter passing conventions of the VESA BIOS
;     -- put VGA into 256 color plane mode ("MODE X")
;     -- etc...
;  There should be one entry in the table for every non-zero
;  'setup_procedure_index' in the text and graphics mode tables.
;  The first entry in the table belongs to index 100h, and so on.
;  The special setup procedure is invoked via a near call.
;
;  Entry: DI=address of the mode record from the text or graphics
;      table to set up.
;
;  Exit:  Adapter configured
;      BX=driver mode word as it should be returned by the mode set
;         routine. Typically it involves picking up the mode word
;         from the header and OR-ing in the appropriate bitplane mode
;         bitfield. (This is not needed for text modes)
;      AX, CX, DX, SI can be trashed, PRESERVE DI!!!!
;
;  NOTE: This runs in real mode, but don't mess with the segment registers.
;--------------------------------------------------------------------------
special_setup_table    label word
    dw    offset  VESA_SVGA_mode_set    ; for 01xxh modes
    dw    offset  VESA_S3_mode_set    ; for 02xxh accelerated S3 modes
    dw    0
    dw    offset  VGA_28_row_mode_set    ; for 28 row text modes
    dw    offset  VGA_28_row_mode_set    ; for 28 row VESA text modes
    dw    offset  VGA_50_row_mode_set    ; for 50 row text modes
    dw    offset  VGA_50_row_mode_set    ; for 50 row VESA text modes

;
; Routine to set up VGA 50 row mode
; interface is described above
;
VGA_50_row_mode_set    proc    near
    mov    ax,WORD PTR [di+6]    ; get base mode number
    and    ah,1            ; clear setup proc index
    je    std_50_mode
    mov    bx,ax
    mov    ax,4f02h
    int    10h
    cmp    ax,004fh        ; VESA error ?
    je    mode_50_done
    mov    ax,3            ; VESA error -- set 80x25 mode
std_50_mode:
    int    10h
mode_50_done:
    xor    bx,bx
    mov    ax,1112h        ; load 8x8 font
    int    10h
    ret
VGA_50_row_mode_set    endp

;
; Routine to set up VGA 28 row mode
; interface is described above
;
VGA_28_row_mode_set     proc     near
    mov    ax,WORD PTR [di+6]    ; get base mode number
    and    ah,1            ; clear setup proc index
    je    std_28_mode
    mov    bx,ax
    mov    ax,4f02h
    int    10h
    cmp    ax,004fh        ; VESA error ?
    je    mode_28_done
    mov    ax,3            ; VESA error -- set 80x25 mode
std_28_mode:
    int    10h
mode_28_done:
    xor    bx,bx
    mov    ax,1111h        ; load 8x14 font
    int    10h
    ret
VGA_28_row_mode_set     endp

;
; Routine to set up VESA SVGA modes
; only used for 16 color text and graphics modes
; interface is described above
;
VESA_SVGA_mode_set    proc    near
    mov    ax,4f02h
    mov    bx,WORD PTR [di+6]
    int    10h
    mov    bx,0ffffh        ; error code
    cmp    ax,004fh
    jne    VESA_SVGA_error
    mov    bx,mode_W
    or    bx,GRD_4_PLANES
VESA_SVGA_error:
    ret
VESA_SVGA_mode_set    endp

; Routine to set up VESA S3 modes
; only used for 256 color graphics modes
; interface is described above
;
VESA_S3_mode_set    proc    near
    mov    ax,4f02h
    mov    bx,WORD PTR [di+6]
    int    10h
    mov    bx,0ffffh        ; error code
    cmp    ax,004fh
    jne    VESA_S3_error
    mov    bx,mode_W
    xor    bx,(GRD_VGA XOR GRD_S3)
    or    bx,GRD_8_PLANES
VESA_S3_error:
    ret
VESA_S3_mode_set    endp


;--------------------------------------------------------------------------
; DRIVER INIT ROUTINE
;  called once after the driver is loaded
;  may do one or more of the followings:
;    - check for proper board type
;    - check amount of RAM on board, and:
;    -- update word in header to reflect correct amount
;    -- disable modes in the tables for which there is not enough RAM
;    - check for special equipment (HiColor DAC, etc...)
;
;  Entry: nothing
;
;  Exit:  AX=status:
;       non-zero: OK,
;       0: something went wrong (e.g. wrong adapter, etc..)
;      BX,CX,DX may be trashed
;
;  NOTE: This runs in real mode, but don't mess with the segment registers.
;--------------------------------------------------------------------------
driver_init_routine    proc    far
    push    di
    push    es
    sub    sp,256
    mov    di,sp
    mov    ax,ss
    mov    es,ax
    mov    ax,4f00h
    int    10h        ; check for VESA BIOS
    cmp    ax,004fh
    jne    init_error
    cmp    BYTE PTR es:[di+0],'V'
    jne    init_error
    cmp    BYTE PTR es:[di+1],'E'
    jne    init_error
    cmp    BYTE PTR es:[di+2],'S'
    jne    init_error
    cmp    BYTE PTR es:[di+3],'A'
    jne    init_error
    mov    ax,1        ; OK, VESA BIOS found
    jmp    init_done
init_error:
    xor    ax,ax
init_done:
    add    sp,256
    pop    es
    pop    di
    ret
driver_init_routine    endp


;--------------------------------------------------------------------------
; MODE SET ROUTINE
;  sets up a text or graphics mode as close as possible to the one
;  reguested by the user with regard to number of colors and size.
;
;  Entry: AX=mode selection
;     0 = 80x25 text
;     1 = default text
;     2 = text CX cols by DX rows
;     3 = biggest text
;     4 = 320x200 graphics
;     5 = default graphics
;     6 = graphics CX width by DX height
;     7 = biggest non-interlaced graphics
;     8 = biggest graphics
;     9 = graphics BX colors, CX width by DX height
;
;  Exit: BX=driver mode flag
;     CX=width (in pixels or characters)
;     DX=height
;
;  NOTE: This runs in real mode, but don't mess with the segment registers.
;     YOU SHOULD NOT NEED TO CHANGE THIS ROUTINE AS IT IS PRETTY
;     MUCH TABLE DRIVEN
;--------------------------------------------------------------------------
mode_set_routine    proc    far
    push    ds
    push    di
    push    si
    mov    si,cs
    mov    ds,si
    cmp    ax,9
    jbe    DoIt
    jmp    Exit
DoIt:    add    ax,ax
    mov    si,ax
    jmp    WORD PTR mode_set_table[si]
mode_set_table  label    word
    dw    offset mode_0
    dw    offset mode_1
    dw    offset mode_2
    dw    offset mode_3
    dw    offset mode_4
    dw    offset mode_5
    dw    offset mode_6
    dw    offset mode_7
    dw    offset mode_8
    dw    offset mode_9
mode_0: mov    si,offset text_mode_table    ; 80x25 text
    mov    bx,def_nc
    mov    cx,80
    mov    dx,25
    jmp    Lookup
mode_1: mov    si,offset text_mode_table    ; default text
    mov    bx,def_nc
    mov    cx,def_tw
    mov    dx,def_th
    jmp    Lookup
mode_2: mov    si,offset text_mode_table    ; CX*DX text
    mov    bx,def_nc
    jmp    Lookup
mode_3: mov    si,offset text_mode_table    ; biggest text
    mov    bx,def_nc
    mov    cx,Max_TW
    mov    dx,Max_TH
    jmp    Lookup
mode_4: mov    si,offset graphics_mode_table    ; 320x200 graphics
    mov    bx,def_nc
    mov    cx,320
    mov    dx,200
    jmp    Lookup
mode_5: mov    si,offset graphics_mode_table    ; default graphics
    mov    bx,def_nc
    mov    cx,def_gw
    mov    dx,def_gh
    jmp    Lookup
mode_6: mov    si,offset graphics_mode_table    ; CX*DX graphics
    mov    bx,def_nc
    jmp    Lookup
mode_7: mov    si,offset graphics_mode_table    ; biggest non-interlaced gr
    mov    bx,def_nc
    mov    cx,Max_GWn
    mov    dx,Max_GHn
    jmp    Lookup
mode_8: mov    si,offset graphics_mode_table    ; biggest graphics
    mov    bx,def_nc
    mov    cx,Max_GW
    mov    dx,Max_GH
    jmp    Lookup
mode_9: mov    si,offset graphics_mode_table    ; CX*DX graphics w/ BX colors
;
; At this point:
;   SI points to the table to search (text or graphics)
;   BX has colors
;   CX has width
;   DX has height
;
Lookup: xor    ax,ax                ; last color number seen
Find_C: cmp    [si+4],ax            ; last color number == this?
    je    Same_C
    jb    Prev_C                ; end of table -- use last color
    cmp    BYTE PTR [si+6],0ffh        ; valid entry ?
    je    Prev_C                ; not -- use last color
    mov    ax,[si+4]            ; record color number
    mov    di,si                ; start of entries w/ this color
    cmp    ax,bx                ; enough colors ?
    jae    Find_S
Same_C: add    si,8
    jmp    Find_C
Prev_C: or    ax,ax                ; found any color at all?
    je    Exit
;
; At this point:
;   DI points into the table to the first entry with the desired color
;      number (either it has enough colors or it is the highest color
;      number supported by the driver). Additionally, at least the
;      first (= smallest size) entry for this color is valid (has a
;      valid BIOS number).
;   AX has the color number adjusted for the driver
;   CX has width
;   DX has height
;
Find_S: cmp    [di+4],ax            ; still the same color #?
    jne    Prev_S
    cmp    BYTE PTR [di+6],0ffh        ; valid entry ?
    je    Prev_S
    cmp    [di],cx
    jb    Next_S
    cmp    [di+2],dx
    jae    GotIt
Next_S: add    di,8
    jmp    Find_S
Prev_S: sub    di,8
;
; At this point:
;   DI points to the table entry we want to set up
;
GotIt:  mov    ax,[di+6]            ; BIOS mode number
    or    ah,ah                ; special ?
    je    doBIOS
    mov    al,ah
    xor    ah,ah
    dec    ax
    add    ax,ax
    mov    si,ax
    call    WORD PTR special_setup_table[si]
    jmp    RetVal
doBIOS: int    10h
    mov    bx,GRD_1_PLANE
    cmp    WORD PTR [di+4],2        ; 2 colors ?
    je    doFLAG
    mov    bx,GRD_4_PLANES
    cmp    WORD PTR [di+4],16        ; 16 colors ?
    je    doFLAG
    mov    bx,GRD_8_PLANES
    cmp    WORD PTR [di+4],256        ; 256 colors ?
    je    doFLAG
    mov    bx,GRD_16_PLANES
    cmp    WORD PTR [di+4],32768        ; 32K colors ?
    je    doFLAG
    mov    bx,GRD_PLANE_MASK        ; something is wrong!!
doFLAG: or    bx,mode_W
RetVal: mov    cx,[di]
    mov    dx,[di+2]
Exit:    pop    si
    pop    di
    pop    ds
    ret
mode_set_routine    endp


;--------------------------------------------------------------------------
; PAGING ROUTINE
;
;  Entry: AH=read page
;      AL=write page
;
;  Exit: VGA configured.
;     AX,BX,CX,DX,SI,DI may be trashed
;
;  NOTE: This runs in protected mode!  Don't mess with the segment registers!
;     This code must be relocatable and may not reference any data!
;--------------------------------------------------------------------------
    assume  ds:nothing, es:nothing

paging_routine  proc    far
    mov    cl,al                ; save for later
    mov    ax,4838h            ; Unlock S3
    mov    dx,3d4h
    out    dx,ax
    mov    al,31h                ; turn on  paging
    out    dx,al
    inc    dx
    in    al,dx
    or    al,1
    out    dx,al
    dec    dx
    mov    al,35h                ; index CRT Reg. Lock
    out    dx,al
    inc    dx                ; read CRT Reg. Lock
    in    al,dx
    and    al,0f0h                ; update with new bank
    or    al,cl
    out    dx,al                ; write CRT Reg. Lock
    mov    ax,0038h            ; Lock S3
    dec    dx
    out    dx,ax
    ret
paging_routine  endp

_TEXT    ends
    end