ref: 21947578303cdb0fcb4b0cdfe80aa9dab5f6b447
dir: /os/pc/vgatvp3020.c/
#include "u.h"
#include "../port/lib.h"
#include "mem.h"
#include "dat.h"
#include "fns.h"
#include "../port/error.h"
#define Image IMAGE
#include <draw.h>
#include <memdraw.h>
#include <cursor.h>
#include "screen.h"
/*
* TVP3020 Viewpoint Video Interface Pallette.
* Assumes hooked up to an S3 86C928.
*/
enum {
Index = 0x06, /* Index register */
Data = 0x07, /* Data register */
};
/*
* Lower 2-bits of indirect DAC register
* addressing.
*/
static ushort dacxreg[4] = {
PaddrW, Pdata, Pixmask, PaddrR
};
static uchar
tvp3020io(uchar reg, uchar data)
{
uchar crt55;
crt55 = vgaxi(Crtx, 0x55) & 0xFC;
vgaxo(Crtx, 0x55, crt55|((reg>>2) & 0x03));
vgao(dacxreg[reg & 0x03], data);
return crt55;
}
static void
tvp3020xo(uchar index, uchar data)
{
uchar crt55;
crt55 = tvp3020io(Index, index);
vgao(dacxreg[Data & 0x03], data);
vgaxo(Crtx, 0x55, crt55);
}
static void
tvp3020disable(VGAscr*)
{
uchar r;
/*
* Disable
* cursor;
* cursor control enable for Bt485 DAC (!);
* the hardware cursor external operation mode.
*/
tvp3020xo(0x06, 0x10); /* Cursor Control Register */
r = vgaxi(Crtx, 0x45) & ~0x20;
vgaxo(Crtx, 0x45, r);
r = vgaxi(Crtx, 0x55) & ~0x20;
vgaxo(Crtx, 0x55, r);
}
static void
tvp3020enable(VGAscr*)
{
uchar r;
/*
* Make sure cursor is off by initialising the cursor
* control to defaults + X-Windows cursor mode.
*/
tvp3020xo(0x06, 0x10); /* Cursor Control Register */
/*
* Overscan colour,
* cursor colour 1 (white),
* cursor colour 2 (black).
*/
tvp3020xo(0x20, Pwhite); tvp3020xo(0x21, Pwhite); tvp3020xo(0x22, Pwhite);
tvp3020xo(0x23, Pwhite); tvp3020xo(0x24, Pwhite); tvp3020xo(0x25, Pwhite);
tvp3020xo(0x26, Pblack); tvp3020xo(0x27, Pblack); tvp3020xo(0x28, Pblack);
/*
* Finally, enable
* the hardware cursor external operation mode;
* cursor control enable for Bt485 DAC (!).
*/
r = vgaxi(Crtx, 0x55)|0x20;
vgaxo(Crtx, 0x55, r);
r = vgaxi(Crtx, 0x45)|0x20;
vgaxo(Crtx, 0x45, r);
}
static void
tvp3020load(VGAscr*, Cursor* curs)
{
uchar p, p0, p1;
int x, y;
/*
* Make sure cursor is off by initialising the cursor
* control to defaults + X-Windows cursor mode.
*/
tvp3020xo(0x06, 0x10); /* Cursor Control Register */
/*
* Initialise the cursor RAM LS and MS address
* (LS must be first).
*/
tvp3020xo(0x08, 0x00); /* Cursor RAM LS Address */
tvp3020xo(0x09, 0x00); /* Cursor RAM MS Address */
/*
* Initialise the 64x64 cursor RAM array. There are 2 planes,
* p0 and p1. Data is written 4 pixels per byte, with p1 the
* MS bit of each pixel.
* The cursor is set in X-Windows mode which gives the following
* truth table:
* p1 p0 colour
* 0 0 underlying pixel colour
* 0 1 underlying pixel colour
* 1 0 cursor colour 1
* 1 1 cursor colour 2
* Put the cursor into the top-left of the 64x64 array.
*/
for(y = 0; y < 64; y++){
for(x = 0; x < 64/8; x++){
if(x < 16/8 && y < 16){
p0 = curs->clr[x+y*2];
p1 = curs->set[x+y*2];
p = 0x00;
if(p1 & 0x10)
p |= 0x03;
else if(p0 & 0x10)
p |= 0x02;
if(p1 & 0x20)
p |= 0x0C;
else if(p0 & 0x20)
p |= 0x08;
if(p1 & 0x40)
p |= 0x30;
else if(p0 & 0x40)
p |= 0x20;
if(p1 & 0x80)
p |= 0xC0;
else if(p0 & 0x80)
p |= 0x80;
tvp3020xo(0x0A, p); /* Cursor RAM Data */
p = 0x00;
if(p1 & 0x01)
p |= 0x03;
else if(p0 & 0x01)
p |= 0x02;
if(p1 & 0x02)
p |= 0x0C;
else if(p0 & 0x02)
p |= 0x08;
if(p1 & 0x04)
p |= 0x30;
else if(p0 & 0x04)
p |= 0x20;
if(p1 & 0x08)
p |= 0xC0;
else if(p0 & 0x08)
p |= 0x80;
tvp3020xo(0x0A, p); /* Cursor RAM Data */
}
else{
tvp3020xo(0x0A, 0x00); /* Cursor RAM Data */
tvp3020xo(0x0A, 0x00);
}
}
}
/*
* Initialise the cursor hotpoint
* and enable the cursor.
*/
tvp3020xo(0x04, -curs->offset.x); /* Sprite Origin X */
tvp3020xo(0x05, -curs->offset.y); /* Sprite Origin Y */
tvp3020xo(0x06, 0x40|0x10); /* Cursor Control Register */
}
static int
tvp3020move(VGAscr*, Point p)
{
tvp3020xo(0x00, p.x & 0xFF); /* Cursor Position X LSB */
tvp3020xo(0x01, (p.x>>8) & 0x0F); /* Cursor Position X MSB */
tvp3020xo(0x02, p.y & 0xFF); /* Cursor Position Y LSB */
tvp3020xo(0x03, (p.y>>8) & 0x0F); /* Cursor Position Y MSB */
return 0;
}
VGAcur vgatvp3020cur = {
"tvp3020hwgc",
tvp3020enable,
tvp3020disable,
tvp3020load,
tvp3020move,
};