diff options
Diffstat (limited to 'arch/x86/machine/vga.c')
| -rw-r--r-- | arch/x86/machine/vga.c | 184 |
1 files changed, 0 insertions, 184 deletions
diff --git a/arch/x86/machine/vga.c b/arch/x86/machine/vga.c deleted file mode 100644 index 08b72332..00000000 --- a/arch/x86/machine/vga.c +++ /dev/null @@ -1,184 +0,0 @@ -/* - * Copyright (c) 2010, 2012 Richard Braun. - * - * This program 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 3 of the License, or - * (at your option) any later version. - * - * This program 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 this program. If not, see <http://www.gnu.org/licenses/>. - */ - -#include <kern/init.h> -#include <kern/macros.h> -#include <kern/stdint.h> -#include <kern/string.h> -#include <machine/io.h> -#include <machine/pmap.h> -#include <machine/vga.h> - -/* - * Screen dimensions. - */ -#define VGA_COLUMNS 80 -#define VGA_LINES 25 - -/* - * Text mode mapped memory and size. - */ -#define VGA_MEMORY 0xb8000 -#define VGA_MEMORY_SIZE (VGA_COLUMNS * VGA_LINES * 2) - -/* - * I/O ports. - */ -#define VGA_MISC_OUTPUT_REGISTER_READ 0x3cc -#define VGA_MISC_OUTPUT_REGISTER_WRITE 0x3c2 -#define VGA_CRTC_ADDRESS_REGISTER 0x3d4 -#define VGA_CRTC_DATA_REGISTER 0x3d5 - -/* - * CRTC registers. - */ -#define VGA_CRTC_CURSOR_LOCATION_HIGH_REGISTER 0xe -#define VGA_CRTC_CURSOR_LOCATION_LOW_REGISTER 0xf - -/* - * Foreground screen color. - */ -#define VGA_FOREGROUND_COLOR 0x7 - -/* - * Blank space 16 bits word. - */ -#define VGA_BLANK ((VGA_FOREGROUND_COLOR << 8) | ' ') - -/* - * Number of spaces to display for a tabulation. - */ -#define VGA_TABULATION_SPACES 8 - -static uint8_t *vga_memory; -static uint16_t vga_cursor; - -static uint16_t -vga_get_cursor_position(void) -{ - uint16_t tmp; - - io_write_byte(VGA_CRTC_ADDRESS_REGISTER, - VGA_CRTC_CURSOR_LOCATION_HIGH_REGISTER); - tmp = io_read_byte(VGA_CRTC_DATA_REGISTER) << 8; - io_write_byte(VGA_CRTC_ADDRESS_REGISTER, - VGA_CRTC_CURSOR_LOCATION_LOW_REGISTER); - tmp |= io_read_byte(VGA_CRTC_DATA_REGISTER); - - return tmp; -} - -static void -vga_set_cursor_position(uint16_t position) -{ - io_write_byte(VGA_CRTC_ADDRESS_REGISTER, - VGA_CRTC_CURSOR_LOCATION_HIGH_REGISTER); - io_write_byte(VGA_CRTC_DATA_REGISTER, position >> 8); - io_write_byte(VGA_CRTC_ADDRESS_REGISTER, - VGA_CRTC_CURSOR_LOCATION_LOW_REGISTER); - io_write_byte(VGA_CRTC_DATA_REGISTER, position & 0xff); -} - -static uint8_t -vga_get_cursor_column(void) -{ - return vga_cursor % VGA_COLUMNS; -} - -void __init -vga_setup(void) -{ - uint8_t misc_output_register; - unsigned long va; - - va = pmap_bootalloc(1); - pmap_kenter(va, VGA_MEMORY); - vga_memory = (uint8_t *)va; - - /* - * Check if the Input/Output Address Select bit is set. - */ - misc_output_register = io_read_byte(VGA_MISC_OUTPUT_REGISTER_READ); - - if (!(misc_output_register & 0x1)) { - /* - * Set the I/O AS bit. - */ - misc_output_register |= 0x1; - - /* - * Update the misc output register. - */ - io_write_byte(VGA_MISC_OUTPUT_REGISTER_WRITE, misc_output_register); - } - - vga_cursor = vga_get_cursor_position(); -} - -static void -vga_scroll_lines(void) -{ - uint16_t *last_line; - int i; - - memmove(vga_memory, (uint16_t *)vga_memory + VGA_COLUMNS, - VGA_MEMORY_SIZE - (VGA_COLUMNS * 2)); - last_line = (uint16_t *)vga_memory + (VGA_COLUMNS * (VGA_LINES - 1)); - - for(i = 0; i < VGA_COLUMNS; i++) - last_line[i] = VGA_BLANK; -} - -void -vga_write_byte(uint8_t byte) -{ - if (byte == '\r') - return; - else if (byte == '\n') { - vga_cursor += VGA_COLUMNS - vga_get_cursor_column(); - - if (vga_cursor >= (VGA_LINES * VGA_COLUMNS)) { - vga_scroll_lines(); - vga_cursor -= VGA_COLUMNS; - } - - vga_set_cursor_position(vga_cursor); - } else if (byte == '\b') { - if (vga_cursor > 0) { - vga_cursor--; - ((uint16_t *)vga_memory)[vga_cursor] = VGA_BLANK; - vga_set_cursor_position(vga_cursor); - } - } else if (byte == '\t') { - int i; - - for(i = 0; i < VGA_TABULATION_SPACES; i++) - vga_write_byte(' '); - } else { - if ((vga_cursor + 1) >= VGA_COLUMNS * VGA_LINES) { - vga_scroll_lines(); - vga_cursor -= VGA_COLUMNS; - } - - ((uint16_t *)vga_memory)[vga_cursor] = ((VGA_FOREGROUND_COLOR << 8) - | byte); - vga_cursor++; - vga_set_cursor_position(vga_cursor); - } -} - -void console_write_byte(char c) __alias("vga_write_byte"); |