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/*
*
* modified from linuxbios code
* by Cai Qiang <rimy2000@hotmail.com>
*
*/
#include "stddef.h"
#include "string.h"
#include <gpxe/io.h>
#include "console.h"
#include <gpxe/init.h>
#include "vga.h"
struct console_driver vga_console;
static char *vidmem; /* The video buffer */
static int video_line, video_col;
#define VIDBUFFER 0xB8000
static void memsetw(void *s, int c, unsigned int n)
{
unsigned int i;
u16 *ss = (u16 *) s;
for (i = 0; i < n; i++) {
ss[i] = ( u16 ) c;
}
}
static void video_init(void)
{
static int inited=0;
vidmem = (char *)phys_to_virt(VIDBUFFER);
if (!inited) {
video_line = 0;
video_col = 0;
memsetw(vidmem, VGA_ATTR_CLR_WHT, 2*1024); //
inited=1;
}
}
static void video_scroll(void)
{
int i;
memcpy(vidmem, vidmem + COLS * 2, (LINES - 1) * COLS * 2);
for (i = (LINES - 1) * COLS * 2; i < LINES * COLS * 2; i += 2)
vidmem[i] = ' ';
}
static void vga_putc(int byte)
{
if (byte == '\n') {
video_line++;
video_col = 0;
} else if (byte == '\r') {
video_col = 0;
} else if (byte == '\b') {
video_col--;
} else if (byte == '\t') {
video_col += 4;
} else if (byte == '\a') {
//beep
//beep(500);
} else {
vidmem[((video_col + (video_line *COLS)) * 2)] = byte;
vidmem[((video_col + (video_line *COLS)) * 2) +1] = VGA_ATTR_CLR_WHT;
video_col++;
}
if (video_col < 0) {
video_col = 0;
}
if (video_col >= COLS) {
video_line++;
video_col = 0;
}
if (video_line >= LINES) {
video_scroll();
video_line--;
}
// move the cursor
write_crtc((video_col + (video_line *COLS)) >> 8, CRTC_CURSOR_HI);
write_crtc((video_col + (video_line *COLS)) & 0x0ff, CRTC_CURSOR_LO);
}
struct console_driver vga_console __console_driver = {
.putchar = vga_putc,
.disabled = 1,
};
struct init_fn video_init_fn __init_fn ( INIT_EARLY ) = {
.initialise = video_init,
};
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