matos/drivers/vga.c
2021-01-25 20:05:38 +01:00

167 lines
3.8 KiB
C

#include "vga.h"
#include "io.h"
#include "irq.h"
#include "klibc.h"
static uint vgaBgColor;
static uint vgaColor;
static int line, col;
static volatile short *vga = (short *)VGA_ADDR;
static void clearScreen(uint bgColor);
static void cursorMove(int x, int y);
static void cursorEnable(uint8_t cursor_start, uint8_t cursor_end);
static void printCharDetails(char str, uint color, uint bgColor, int startX, int startY);
int VGASetup(uint bgColor, uint color)
{
vgaBgColor = bgColor;
vgaColor = color;
line = 0;
col = 0;
clearScreen(bgColor);
cursorEnable(14, 15);
return 0;
}
static void clearScreen(uint bgColor)
{
uint32_t flags;
long int colorAttr = bgColor << 12;
disable_IRQs(flags);
for (int i = 0; i < VGA_WIDTH * VGA_HEIGHT; i++) {
vga[i] = colorAttr;
}
restore_IRQs(flags);
}
void VGAclearLine(uint bgColor, uint line)
{
uint32_t flags;
long int colorAttr = bgColor << 12;
if (line >= VGA_HEIGHT)
return;
disable_IRQs(flags);
for (uint i = VGA_WIDTH * line; i < VGA_WIDTH * (line + 1); i++) {
vga[i] = colorAttr;
}
restore_IRQs(flags);
}
void VGAPrintf(uint color, uint bgColor, int startX, int startY, const char *format, ...)
{
int flags;
char tmp[VGA_WIDTH];
int idx = 0;
disable_IRQs(flags);
va_list ap;
va_start(ap, format);
int ret = vsnprintf(tmp, sizeof(tmp), format, ap);
while (ret > 0 && tmp[idx]) {
printCharDetails(tmp[idx++], color, bgColor, startX++, startY);
}
va_end(ap);
restore_IRQs(flags);
}
static void printCharDetails(const char str, uint color, uint bgColor, int startX, int startY)
{
int pos = VGA_WIDTH * startY + startX;
if (pos > VGA_WIDTH * VGA_HEIGHT || pos < 0)
return;
long int colorAttr = (bgColor << 4 | (color & 0x0f)) << 8;
vga[pos] = colorAttr | str;
}
void VGAScrollUp(void)
{
long int colorAttr = vgaBgColor << 12;
int flags;
disable_IRQs(flags);
for (int i = 1; i < VGA_HEIGHT - VGA_STATUS_LINE_HEIGHT;
i++) { // last line is status line. Do not scroll it
memcpy((void *)&vga[VGA_WIDTH * (i - 1)], (void *)&vga[VGA_WIDTH * i],
VGA_WIDTH * sizeof(short));
}
for (int i = 0; i < VGA_WIDTH; i++) {
vga[(VGA_HEIGHT - 1 - VGA_STATUS_LINE_HEIGHT) * VGA_WIDTH + i] = colorAttr;
}
restore_IRQs(flags);
}
void VGAPutc(const char str)
{
int flags;
disable_IRQs(flags);
if (str == '\n') {
line++;
col = 0;
if (line >= VGA_HEIGHT - VGA_STATUS_LINE_HEIGHT) {
VGAScrollUp();
line--;
}
} else if (str == '\r') {
col = 0;
} else if (str == '\b') {
col--;
if (col < 0) {
col = VGA_WIDTH - 1;
line--;
if (line < 0)
line = 0;
}
printCharDetails(' ', vgaColor, vgaBgColor, col, line);
} else {
printCharDetails(str, vgaColor, vgaBgColor, col++, line);
if (col == VGA_WIDTH) {
col = 0;
line++;
}
if (line >= VGA_HEIGHT - VGA_STATUS_LINE_HEIGHT) {
VGAScrollUp();
line--;
}
}
cursorMove(col, line);
restore_IRQs(flags);
}
static void cursorEnable(uint8_t cursor_start, uint8_t cursor_end)
{
outb(0x3D4, 0x0A);
outb(0x3D5, (inb(0x3D5) & 0xC0) | cursor_start);
outb(0x3D4, 0x0B);
outb(0x3D5, (inb(0x3D5) & 0xE0) | cursor_end);
}
void cursorDisable(void)
{
outb(0x3D4, 0x0A);
outb(0x3D5, 0x20);
}
static void cursorMove(int x, int y)
{
long int colorAttr = (vgaBgColor << 4 | (vgaColor & 0x0f)) << 8;
uint16_t pos = y * VGA_WIDTH + x;
vga[pos] = colorAttr;
outb(0x3D4, 0x0F);
outb(0x3D5, (uint8_t)(pos & 0xFF));
outb(0x3D4, 0x0E);
outb(0x3D5, (uint8_t)((pos >> 8) & 0xFF));
}