#![no_std]
#![feature(const_fn)]
#[macro_use]
extern crate bitflags;
extern crate x86_64;
use core::fmt;
use x86_64::instructions::port::Port;
bitflags! {
struct IntEnFlags: u8 {
const RECEIVED = 1;
const SENT = 1 << 1;
const ERRORED = 1 << 2;
const STATUS_CHANGE = 1 << 3;
}
}
bitflags! {
struct LineStsFlags: u8 {
const INPUT_FULL = 1;
const OUTPUT_EMPTY = 1 << 5;
}
}
pub struct SerialPort {
data: Port<u8>,
int_en: Port<u8>,
fifo_ctrl: Port<u8>,
line_ctrl: Port<u8>,
modem_ctrl: Port<u8>,
line_sts: Port<u8>,
}
impl SerialPort {
pub const fn new(base: u16) -> SerialPort {
SerialPort {
data: Port::new(base),
int_en: Port::new(base + 1),
fifo_ctrl: Port::new(base + 2),
line_ctrl: Port::new(base + 3),
modem_ctrl: Port::new(base + 4),
line_sts: Port::new(base + 5),
}
}
pub fn init(&mut self) {
unsafe {
self.int_en.write(0x00);
self.line_ctrl.write(0x80);
self.data.write(0x03);
self.int_en.write(0x00);
self.line_ctrl.write(0x03);
self.fifo_ctrl.write(0xC7);
self.modem_ctrl.write(0x0B);
self.int_en.write(0x01);
}
}
fn line_sts(&self) -> LineStsFlags {
unsafe {
LineStsFlags::from_bits_truncate(self.line_sts.read())
}
}
pub fn send(&mut self, data: u8) {
unsafe {
match data {
8 | 0x7F => {
while !self.line_sts().contains(LineStsFlags::OUTPUT_EMPTY) {}
self.data.write(8);
while !self.line_sts().contains(LineStsFlags::OUTPUT_EMPTY) {}
self.data.write(b' ');
while !self.line_sts().contains(LineStsFlags::OUTPUT_EMPTY) {}
self.data.write(8)
},
_ => {
while !self.line_sts().contains(LineStsFlags::OUTPUT_EMPTY) {}
self.data.write(data);
}
}
}
}
}
impl fmt::Write for SerialPort {
fn write_str(&mut self, s: &str) -> fmt::Result {
for byte in s.bytes() {
self.send(byte);
}
Ok(())
}
}