diff options
Diffstat (limited to 'os/pc/vgatvp3020.c')
| -rw-r--r-- | os/pc/vgatvp3020.c | 216 |
1 files changed, 216 insertions, 0 deletions
diff --git a/os/pc/vgatvp3020.c b/os/pc/vgatvp3020.c new file mode 100644 index 00000000..08871d4a --- /dev/null +++ b/os/pc/vgatvp3020.c @@ -0,0 +1,216 @@ +#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, +}; |