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// MIT License, Copyright (c) 2021 Marvin Borner
#include <cpu.h>
#include <log.h>
#include <panic.h>
#define PORT 0x3f8
void serial_install(void)
{
outb(PORT + 1, 0x00);
outb(PORT + 3, 0x80);
outb(PORT + 0, 0x03);
outb(PORT + 1, 0x00);
outb(PORT + 3, 0x03);
outb(PORT + 2, 0xc7);
// Test serial chip
outb(PORT + 4, 0x1e); // Enable loopback
outb(PORT + 0, 0xae); // Write
assert(inb(PORT + 0) == 0xae); // Verify receive
// Activate
outb(PORT + 4, 0x0f);
log("[LOG] Initiated\n");
}
static int serial_empty(void)
{
return inb(PORT + 5) & 0x20;
}
static void serial_put(char ch)
{
while (serial_empty() == 0)
;
outb(PORT, (u8)ch);
}
void serial_print(const char *data)
{
for (const char *p = data; *p; p++)
serial_put(*p);
}
void log(const char *format, ...)
{
char buf[1024] = { 0 };
va_list ap;
va_start(ap, format);
vsnprintf(buf, sizeof(buf), format, ap);
va_end(ap);
serial_print(buf);
}
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