kernel2/vga.c

   1 /*
   2     meinOS - A unix-like x86 microkernel operating system
   3     Copyright (C) 2008  Janosch Gräf <janosch.graef@gmx.net>
   4
   5     This program is free software: you can redistribute it and/or modify
   6     it under the terms of the GNU General Public License as published by
   7     the Free Software Foundation, either version 3 of the License, or
   8     (at your option) any later version.
   9
  10     This program is distributed in the hope that it will be useful,
  11     but WITHOUT ANY WARRANTY; without even the implied warranty of
  12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13     GNU General Public License for more details.
  14
  15     You should have received a copy of the GNU General Public License
  16     along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17 */
  18
  19 #include <string.h>
  20 #include <ctype.h>
  21 #include <ioport.h>
  22 #include <vga.h>
  23
  24 /**
  25  * Initializes VGA
  26  */
  27 void vga_init() {
  28   com_init();
  29   vga_text_video = (vga_text_char_t*)VGA_TEXT_ADDRESS;
  30   vga_text_set_hwcursor(0,VGA_TEXT_HEIGHT+1);
  31   vga_text_clear();
  32 }
  33
  34 /**
  35  * Clears VGA text screen
  36  */
  37 void vga_text_clear() {
  38   vga_text_cursor.x = 0;
  39   vga_text_cursor.y = 0;
  40   vga_text_cursor.color = VGA_TEXT_COLOR_DEFAULT;
  41   // trick: just set whole screen with bg color as bg and front color
  42   memset(vga_text_video,(vga_text_cursor.color&0xF0)|(vga_text_cursor.color>>4),VGA_TEXT_SIZE);
  43 }
  44
  45 /**
  46  * Moves VGA text hardware cursor
  47  *  @param x New X position
  48  *  @param y New Y position
  49  */
  50 void vga_text_set_hwcursor(int x,int y) {
  51   int off = y*VGA_TEXT_WIDTH+x;
  52
  53   outb(0x3D4,14);
  54   outb(0x3D5,off>>8);
  55   outb(0x3D4,15);
  56   outb(0x3D5,off);
  57 }
  58
  59 /**
  60  * Set color of next chars
  61  *  @param color Color
  62  */
  63 void vga_text_setcolor(vga_text_color_t color) {
  64   vga_text_cursor.color = color;
  65 }
  66
  67 /**
  68  * Prints character to VGA text screen
  69  */
  70 void vga_text_printchar(char chr) {
  71   if (chr=='\b') vga_text_cursor.x = vga_text_cursor.x>0?vga_text_cursor.x-1:vga_text_cursor.x;
  72   else if (chr=='\r') vga_text_cursor.x = 0;
  73   else if (chr=='\n') {
  74     vga_text_cursor.y++;
  75     vga_text_cursor.x = 0;
  76   }
  77   else if (chr=='\f') vga_text_clear();
  78   else if (chr=='\t') vga_text_cursor.x = vga_text_cursor.x = vga_text_cursor.x>0?(vga_text_cursor.x/VGA_TEXT_TABSIZE+1)*VGA_TEXT_TABSIZE:0;
  79   else if (isprint(chr)) {
  80     int off = vga_text_cursor.x+vga_text_cursor.y*VGA_TEXT_WIDTH;
  81     if (off==0x3FD) asm("hlt"::"a"(0xD00FC0DE));
  82     vga_text_video[off].chr = chr;
  83     vga_text_video[off].attr = vga_text_cursor.color;
  84     vga_text_cursor.x++;
  85   }
  86
  87   com_send(chr);
  88   bochs_send(chr);
  89
  90   if (vga_text_cursor.x>=VGA_TEXT_WIDTH) {
  91     vga_text_cursor.x = 0;
  92     vga_text_cursor.y++;
  93   }
  94   if (vga_text_cursor.y>=VGA_TEXT_HEIGHT) {
  95     memmove(vga_text_video,vga_text_video+VGA_TEXT_WIDTH,VGA_TEXT_WIDTH*(VGA_TEXT_HEIGHT-1)*VGA_TEXT_BPC);
  96     memset(vga_text_video+VGA_TEXT_WIDTH*(VGA_TEXT_HEIGHT-1),(vga_text_cursor.color&0xF0)|(vga_text_cursor.color>>4),VGA_TEXT_WIDTH*VGA_TEXT_BPC);
  97     vga_text_cursor.y = VGA_TEXT_HEIGHT-1;
  98   }
  99 }
 100
 101 /// @todo remove
 102 #define COM_PORT 0x3f8   /* COM1 */
 103 #define BAUDRATE 9600
 104 void com_init() {
 105   int baud = 115200/BAUDRATE;
 106   // Keine Parität
 107   outb(COM_PORT+1,0x00); // no interrupts
 108   outb(COM_PORT+3,0x80); // dlab
 109   outb(COM_PORT+0,baud); // Baudrate (low)
 110   outb(COM_PORT+1,baud>>8); // Baudrate (high)
 111   outb(COM_PORT+3,0x03); // 8 Bits, 1 stopbit
 112   outb(COM_PORT+2,0xC7);
 113   outb(COM_PORT+4,0x0B);
 114 }
 115 int is_transmit_empty() {
 116   return inb(COM_PORT+5)&0x20;
 117 }
 118 void com_send(char a) {
 119   while (!is_transmit_empty());
 120   outb(COM_PORT,a);
 121 }
 122
 123 #define BOCHS_PORT 0xE9
 124 void bochs_send(char a) {
 125   outb(BOCHS_PORT,a);
 126 }