SvgaLib/obsolete/svpmi/svpmi.c

185 lines
4 KiB
C

/* This library is free software; you can redistribute it and/or */
/* modify it without any restrictions. This library is distributed */
/* in the hope that it will be useful, but without any warranty. */
/* Copyright (C) 1994 Harm Hanemaayer */
/*
Basic initial untested SVPMI skeleton driver.
Includes computer-generated mode setting/bank switching
routines and mode information table.
Untested, may not be finished.
A better way to do this would be to have a seperate svpmi server
program set modes. This way there would be no need to recompile
the shared library. For performance it would be nice to move the
bank-switching over to svgalib. I imagine one way to do this would
be to encode the SVPMI procedure code (simple as it is, just a few
outs and a few basic bit operations) and have the svgalib driver
interpret that. This could also be used for mode setting.
*/
#include <stdio.h>
#include "../vga.h"
#include "../libvga.h"
#include "../driver.h"
#include "svpmi.h"
#include "modes.svpmi"
#include "modetable.svpmi"
static svpmi_currentmode = NULL;
static svpmi_modeentry *
svpmi_lookupmode (int w, int h, int colors)
{
int i;
for (i = 0; i < sizeof (svpmi_modes); i++)
if (w == svpmi_modes[i].width && h == svpmi_modes[i].height &&
colors = (1 << svpmi_mode[i].bitsperpixel))
return &svpmi_modes[i];
return NULL;
}
static int
svpmi_getmodeinfo (int mode, vga_modeinfo * modeinfo)
{
modeinfo->maxlogicalwidth = modeinfo->width;
modeinfo->startaddressrange = 0;
modeinfo->haveblit = 0;
modeinfo->flags &= ~HAVE_RWPAGE;
return 0;
}
/* Return non-zero if mode is available */
static int
svpmi_modeavailable (int mode)
{
struct info *info;
svpmi_modeentry *sm;
if (mode < 10)
return vga_chipsetfunctions[CHIPSET_MODEAVAILABLE] (mode);
if (mode == 32)
return 0;
sm = svpmi_lookupmode (modeinfo->width, modeinfo->height,
modeinfo->colors);
return (sm != NULL)
}
/* Set a mode */
static int
svpmi_setmode (int mode, int prv_mode)
{
svpmi_modeentry *sm;
if (mode == TEXT)
{
svpmi_setmode_text ();
return 0;
}
if (!SVGAMODE (mode))
/* Let the standard VGA driver set standard VGA modes. */
return vga_chipsetfunctions[CHIPSET_SETMODE] (mode);
sm = svpmi_lookupmode (infotable[mode].width, infotable[mode].height,
infotable[mode].colors);
if (sm == NULL)
return 1; /* No match. */
sm->setmode (); /* Call the SVPMI mode setting code. */
svpmi_currentmode = sm;
/* Hack similar to what the ATI mach32 driver does for some */
/* truecolor modes. I think S3 uses only a few fixed scanline */
/* widths (e.g. 1024, 1280) so may happen a lot. */
infotable[mode].xbytes = sm->bytesperscanline;
}
/* Indentify chipset; return non-zero if detected */
static int
svpmi_test ()
{
/* Detection with environment variable -- better change into */
/* config file option. */
if (getenv ("SVGALIB_SVPMI"))
return 1;
return 0;
}
/* Bank switching function - set 64K bank number */
static void
svpmi_setpage (int page)
{
svpmi_currentmode->setwindow (page *
(64 / svpmi_currentmode->windowgranularity));
}
/* Set display start address (not for 16 color modes) */
static int
svpmi_setdisplaystart (int address)
{
}
/* Set logical scanline length (usually multiple of 8) */
/* Multiples of 8 to 2040 */
static int
svpmi_setlogicalwidth (int width)
{
outw (0x3d4, 0x13 + (width >> 3) * 256); /* lw3-lw11 */
return 0;
}
static int
nothing ()
{
}
/* Function table (exported) */
int (*svpmi_chipsetfunctions[]) () =
{
(int (*)()) nothing, /* saveregs */
(int (*)()) nothing, /* setregs */
(int (*)()) nothing, /* unlock */
(int (*)()) nothing, /* lock */
svpmi_test,
svpmi_init,
(int (*)()) svpmi_setpage,
(int (*)()) nothing,
(int (*)()) nothing,
svpmi_setmode,
svpmi_modeavailable,
nothing, /* setdisplaystart */
svmi_setlogicalwidth,
svpmi_getmodeinfo
};
/* Initialize chipset (called after detection) */
static int
svpmi_init (int force, int par1, int par2)
{
/* Not required. */
}