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dosbox-staging/src/hardware/vga.cpp
2003-10-22 14:53:23 +00:00

165 lines
4.1 KiB
C++

/*
* Copyright (C) 2002-2003 The DOSBox Team
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Library General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#include <stdlib.h>
#include <string.h>
#include "dosbox.h"
#include "video.h"
#include "pic.h"
#include "timer.h"
#include "vga.h"
#include "inout.h"
VGA_Type vga;
Bit32u CGA_2_Table[16];
Bit32u CGA_4_Table[256];
Bit32u CGA_16_Table[256];
Bit32u ExpandTable[256];
Bit32u Expand16Table[4][16];
Bit32u Expand16BigTable[0x10000];
Bit32u FillTable[16];
void VGA_SetMode(VGAModes mode) {
if (vga.mode == mode) return;
vga.mode=mode;
VGA_SetupHandlers();
VGA_StartResize();
}
void VGA_StartResize(void) {
if (!vga.draw.resizing) {
vga.draw.resizing=true;
/* Start a resize after 50 ms */
PIC_AddEvent(VGA_SetupDrawing,50000);
}
}
void VGA_SetClock(Bitu which,Bitu target) {
struct{
Bitu n,m;
Bits err;
} best;
best.err=target;
Bitu n,m,r;
for (r = 0; r <= 3; r++) {
Bitu f_vco = target * (1 << r);
if (MIN_VCO <= f_vco && f_vco < MAX_VCO) break;
}
for (n=1;n<=31;n++) {
m=(target * (n + 2) * (1 << r) + (S3_CLOCK_REF/2)) / S3_CLOCK_REF - 2;
if (0 <= m && m <= 127) {
Bitu temp_target = S3_CLOCK(m,n,r);
Bits err = target - temp_target;
if (err < 0) err = -err;
if (err < best.err) {
best.err = err;
best.m = m;
best.n = n;
}
}
}
/* Program the s3 clock chip */
vga.s3.clk[which].m=best.m;
vga.s3.clk[which].r=r;
vga.s3.clk[which].n=best.n;
VGA_StartResize();
}
void VGA_Init(Section* sec) {
vga.draw.resizing=false;
VGA_SetupMemory();
VGA_SetupMisc();
VGA_SetupDAC();
VGA_SetupGFX();
VGA_SetupSEQ();
VGA_SetupAttr();
VGA_SetClock(0,CLK_25);
VGA_SetClock(1,CLK_28);
/* Generate tables */
Bitu i,j;
for (i=0;i<256;i++) {
ExpandTable[i]=i | (i << 8)| (i <<16) | (i << 24);
#ifdef WORDS_BIGENDIAN
CGA_4_Table[i]=((i>>0)&3) | (((i>>2)&3) << 8)| (((i>>4)&3) <<16) | (((i>>6)&3) << 24);
#else
CGA_4_Table[i]=((i>>6)&3) | (((i>>4)&3) << 8)| (((i>>2)&3) <<16) | (((i>>0)&3) << 24);
#endif
}
for (i=0;i<16;i++) {
#ifdef WORDS_BIGENDIAN
CGA_2_Table[i]=((i>>0)&1) | (((i>>1)&1) << 8)| (((i>>1)&1) <<16) | (((i>>3)&1) << 24);
FillTable[i]= ((i & 1) ? 0xff000000 : 0) |
((i & 2) ? 0x00ff0000 : 0) |
((i & 4) ? 0x0000ff00 : 0) |
((i & 8) ? 0x000000ff : 0) ;
#else
CGA_2_Table[i]=((i>>3)&1) | (((i>>2)&1) << 8)| (((i>>1)&1) <<16) | (((i>>0)&1) << 24);
FillTable[i]= ((i & 1) ? 0x000000ff : 0) |
((i & 2) ? 0x0000ff00 : 0) |
((i & 4) ? 0x00ff0000 : 0) |
((i & 8) ? 0xff000000 : 0) ;
#endif
}
for (j=0;j<4;j++) {
for (i=0;i<16;i++) {
#ifdef WORDS_BIGENDIAN
Expand16Table[j][i] =
((i & 1) ? 1 << j : 0) |
((i & 2) ? 1 << (8 + j) : 0) |
((i & 4) ? 1 << (16 + j) : 0) |
((i & 8) ? 1 << (24 + j) : 0);
#else
Expand16Table[j][i] =
((i & 1) ? 1 << (24 + j) : 0) |
((i & 2) ? 1 << (16 + j) : 0) |
((i & 4) ? 1 << (8 + j) : 0) |
((i & 8) ? 1 << j : 0);
#endif
}
}
for (i=0;i<0x10000;i++) {
Bit32u val=0;
if (i & 0x1) val|=0x1 << 24;
if (i & 0x2) val|=0x1 << 16;
if (i & 0x4) val|=0x1 << 8;
if (i & 0x8) val|=0x1 << 0;
if (i & 0x10) val|=0x4 << 24;
if (i & 0x20) val|=0x4 << 16;
if (i & 0x40) val|=0x4 << 8;
if (i & 0x80) val|=0x4 << 0;
if (i & 0x100) val|=0x2 << 24;
if (i & 0x200) val|=0x2 << 16;
if (i & 0x400) val|=0x2 << 8;
if (i & 0x800) val|=0x2 << 0;
if (i & 0x1000) val|=0x8 << 24;
if (i & 0x2000) val|=0x8 << 16;
if (i & 0x4000) val|=0x8 << 8;
if (i & 0x8000) val|=0x8 << 0;
Expand16BigTable[i]=val;
}
}