root / Whitix / branches / scheduler / video / switch.c

/*  This file is part of Whitix.
 *
 *  Whitix 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.
 *
 *  Whitix 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 General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with Whitix; if not, write to the Free Software
 *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 *
 */

#include <console.h>
#include <fs/devfs.h>
#include <fs/vfs.h>
#include <init.h>
#include <error.h>
#include <malloc.h>
#include <i386/ioports.h>
#include <task.h>

/* TODO: Document. */

#define VGA_ATT_INDEX           0x3C0
#define VGA_ATT_WRITE           0x3C0

#define VGA_SEQ_INDEX           0x3C4
#define VGA_SEQ_DATA            0x3C5

#define VGA_GFX_INDEX           0x3CE
#define VGA_GFX_DATA            0x3CF

#define VGA_CRT_INDEXC          0x3D4
#define VGA_CRT_DATAC           0x3D5

/* VGA: Switch back to text mode, so we can display the error message (most likely). */

BYTE attribRegisters[0x15]={
        0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x14, 0x07,
        0x38, 0x39, 0x3A, 0x3B, 0x3C, 0x3D, 0x3E, 0x3F,
        0x0C, 0x00, 0x0F, 0x08, 0x00,
};

BYTE seqRegisters[5]={
        0x03, 0x00, 0x03, 0x00, 0x02,
};

BYTE gfxRegisters[9]={
        0x00, 0x00, 0x00, 0x00, 0x00, 0x10, 0x0E, 0x0F, 0xFF,
};

BYTE crtcRegisters[0x19]={
        0x5F, 0x4F, 0x50, 0x82, 0x55, 0x81, 0xBF, 0x1F, 0x00, 0x4F,
        0x0D, 0x0E, 0x00, 0x00, 0x00, 0x00, 0x9C, 0x8E, 0x8F, 0x28,
        0x1F, 0x96, 0xB9, 0xA3, 0xFF,
};

void ConsoleSwitchToText()
{
        int i;
        
        /* TODO: No need to switch back if we haven't even established multiple consoles yet. */

        /* Are we already in text mode? */
        if (!(consoles[currConsole].flags & CONSOLE_GRAPHICS))
                return;

        inb(0x3DA);

        for (i=0; i<0x15; i++)
        {
                outb(VGA_ATT_INDEX, i);
                outb(VGA_ATT_WRITE, attribRegisters[i]);
        }

        for (i=0; i<5; i++)
        {
                outb(VGA_SEQ_INDEX, i);
                outb(VGA_SEQ_INDEX, seqRegisters[i]);
        }

        for (i=0; i<9; i++)
        {
                outb(VGA_GFX_INDEX, i);
                outb(VGA_GFX_DATA, gfxRegisters[i]);
        }

        outw(VGA_CRT_INDEXC, 0x0011);

        for (i=0; i<0x19; i++)
        {
                outb(VGA_CRT_INDEXC, i);
                outb(VGA_CRT_DATAC, crtcRegisters[i]);
        }

        outb(0x3C2, 0x67);
        outb(0x3C0, 0x20);      
        inb(0x3DA);

        consoles[currConsole].flags &= ~CONSOLE_GRAPHICS;
}