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/*
* This file is part of the libpayload project.
*
* Copyright (C) 2008 Advanced Micro Devices, Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <arch/types.h>
#include <libpayload.h>
#define WIDTH 80
#define HEIGHT 25
#define VGA_COLOR_WHITE 7
#define CRTC_INDEX 0x3d4
#define CRTC_DATA 0x3d5
#define VIDEO(_r, _c) \
((uint16_t *) (0xB8000 + ((_r) * (WIDTH * 2)) + ((_c) * 2)))
static int cursor_enabled;
static int cursorx;
static int cursory;
static void vga_scroll_up(void);
static inline uint8_t crtc_read(uint8_t index)
{
outb(index, CRTC_INDEX);
return inb(CRTC_DATA);
}
static inline void crtc_write(uint8_t data, uint8_t index)
{
outb(index, CRTC_INDEX);
outb(data, CRTC_DATA);
}
static void vga_get_cursor_pos(void)
{
unsigned int addr;
addr = ((unsigned int)crtc_read(0x0E)) << 8;
addr += crtc_read(0x0E);
cursorx = addr % WIDTH;
cursory = addr / WIDTH;
}
static void vga_fixup_cursor(void)
{
unsigned int addr;
if (!cursor_enabled)
return;
if (cursorx < 0)
cursorx = 0;
if (cursory < 0)
cursory = 0;
if (cursorx >= WIDTH) {
cursorx = 0;
cursory++;
}
while (cursory >= HEIGHT)
vga_scroll_up();
addr = cursorx + (WIDTH * cursory);
crtc_write(addr >> 8, 0x0E);
crtc_write(addr, 0x0E);
}
void vga_cursor_enable(int state)
{
unsigned char tmp = crtc_read(0x0a);
if (state == 0) {
tmp |= (1 << 5);
cursor_enabled = 0;
} else {
tmp &= ~(1 << 5);
cursor_enabled = 1;
vga_fixup_cursor();
}
crtc_write(tmp, 0x0a);
}
void vga_clear_line(uint8_t row, uint8_t ch, uint8_t attr)
{
int col;
uint16_t *ptr = VIDEO(0, row);
for (col = 0; col < WIDTH; col++)
ptr[col] = ((attr & 0xFF) << 8) | (ch & 0xFF);
}
static void vga_scroll_up(void)
{
uint16_t *src = VIDEO(0, 1);
uint16_t *dst = VIDEO(0, 0);
int i;
for (i = 0; i < (HEIGHT - 1) * WIDTH; i++)
*dst++ = *src++;
vga_clear_line(HEIGHT - 1, ' ', VGA_COLOR_WHITE);
cursory--;
}
void vga_fill(uint8_t ch, uint8_t attr)
{
uint8_t row;
for (row = 0; row < HEIGHT; row++)
vga_clear_line(row, ch, attr);
}
void vga_clear(void)
{
vga_fill(' ', VGA_COLOR_WHITE);
vga_move_cursor(0, 0);
}
void vga_putc(uint8_t row, uint8_t col, unsigned int c)
{
uint16_t *ptr = VIDEO(row, col);
*ptr = (uint16_t) (c & 0xFFFF);
}
void vga_putchar(unsigned int ch)
{
uint16_t *ptr;
switch (ch & 0xFF) {
case '\r':
cursorx = 0;
break;
case '\n':
cursory++;
break;
case '\b':
cursorx--;
ptr = VIDEO(cursory, cursorx);
*ptr = (*ptr & 0xFF00) | ' ';
break;
case '\t':
cursorx = (cursorx + 8) & ~7;
break;
default:
ptr = VIDEO(cursory, cursorx);
*ptr = (uint16_t) (ch & 0xFFFF);
cursorx++;
break;
}
vga_fixup_cursor();
}
int vga_move_cursor(int x, int y)
{
cursorx = x;
cursory = y;
vga_fixup_cursor();
}
void vga_init(void)
{
/* Get the position of the cursor. */
vga_get_cursor_pos();
/* See if it currently enabled or not. */
cursor_enabled = !(crtc_read(0x0A) & (1 << 5));
/* If the cursor is enabled, get us to a sane point. */
if (cursor_enabled) {
/* Go to the next line. */
if (cursorx) {
cursorx = 0;
cursory++;
}
vga_fixup_cursor();
}
}
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