initial commit

kernel/.gitignore

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+/target

kernel/Cargo.toml

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+[package]
+name = "kernel"
+version = "0.1.0"
+edition = "2021"
+
+[[bin]]
+name = "kernel"
+test = false
+bench = false
+
+[dependencies]
+bootloader_api = "0.11.5"
+embedded-graphics = "0.8.1"
+uart_16550 = "0.3.0"
+x86_64 = "0.14.11"
+spin = "0.9.8"
+pic8259 = "0.10.1"
+pc-keyboard = "0.5.0"
+
+[dependencies.lazy_static]
+version = "1.4.0"
+features = ["spin_no_std"]
+

kernel/src/framebuffer.rs

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+use bootloader_api::info::FrameBuffer;
+use embedded_graphics::{
+    draw_target::DrawTarget,
+    geometry::{Dimensions, OriginDimensions, Point, Size},
+    mono_font::{ascii::FONT_6X10, MonoTextStyle},
+    pixelcolor::{Rgb888, RgbColor},
+    primitives::{
+        Circle, Primitive, PrimitiveStyle, PrimitiveStyleBuilder, Rectangle, StrokeAlignment,
+        Triangle,
+    },
+    text::{Alignment, Text},
+    Drawable, Pixel,
+};
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub struct Position {
+    pub x: usize,
+    pub y: usize,
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub struct Color {
+    pub red: u8,
+    pub green: u8,
+    pub blue: u8,
+}
+
+pub fn set_pixel_in(framebuffer: &mut FrameBuffer, position: Position, color: Color) {
+    let info = framebuffer.info();
+    let byte_offset = {
+        let line_offset = position.y * info.stride;
+        let pixel_offset = line_offset + position.x;
+        pixel_offset * info.bytes_per_pixel
+    };
+    let pixel_buffer = &mut framebuffer.buffer_mut()[byte_offset..];
+    match info.pixel_format {
+        bootloader_api::info::PixelFormat::Rgb => {
+            pixel_buffer[0] = color.red;
+            pixel_buffer[1] = color.green;
+            pixel_buffer[2] = color.blue;
+        }
+        bootloader_api::info::PixelFormat::Bgr => {
+            pixel_buffer[0] = color.blue;
+            pixel_buffer[1] = color.green;
+            pixel_buffer[2] = color.red;
+        }
+        bootloader_api::info::PixelFormat::U8 => {
+            let gray = color.red / 3 + color.green / 3 + color.blue / 3;
+            pixel_buffer[0] = gray;
+        }
+        other => panic!("unknown pixel format {other:?}"),
+    }
+}
+
+pub struct Display<'a> {
+    framebuffer: &'a mut FrameBuffer,
+}
+
+impl<'a> Display<'a> {
+    pub fn new(framebuffer: &'a mut FrameBuffer) -> Self {
+        Self { framebuffer }
+    }
+
+    fn draw_pixel(&mut self, pos: Position, color: Color) {
+        let (width, height) = {
+            let info = self.framebuffer.info();
+            (info.width, info.height)
+        };
+        if pos.x >= width || pos.y >= height {
+            return;
+        }
+        set_pixel_in(&mut self.framebuffer, pos, color);
+    }
+}
+
+impl OriginDimensions for Display<'_> {
+    fn size(&self) -> embedded_graphics::prelude::Size {
+        let info = self.framebuffer.info();
+        Size {
+            width: info.width as u32,
+            height: info.height as u32,
+        }
+    }
+}
+
+impl DrawTarget for Display<'_> {
+    type Color = Rgb888;
+    type Error = core::convert::Infallible;
+    fn draw_iter<I>(&mut self, pixels: I) -> Result<(), Self::Error>
+    where
+        I: IntoIterator<Item = Pixel<Self::Color>>,
+    {
+        for Pixel(coordinates, color) in pixels.into_iter() {
+            self.draw_pixel(
+                Position {
+                    x: coordinates.x as usize,
+                    y: coordinates.y as usize,
+                },
+                Color {
+                    red: color.r(),
+                    green: color.g(),
+                    blue: color.b(),
+                },
+            );
+        }
+        Ok(())
+    }
+}
+
+pub fn draw_test(framebuffer: &mut FrameBuffer) {
+    for b in framebuffer.buffer_mut() {
+        *b = 0;
+    }
+    let mut display = Display::new(framebuffer);
+    // Create styles used by the drawing operations.
+    let thin_stroke = PrimitiveStyle::with_stroke(Rgb888::new(0, 255, 255), 1);
+    let thick_stroke = PrimitiveStyle::with_stroke(Rgb888::new(0, 255, 255), 3);
+    let border_stroke = PrimitiveStyleBuilder::new()
+        .stroke_color(Rgb888::new(0, 255, 255))
+        .stroke_width(3)
+        .stroke_alignment(StrokeAlignment::Inside)
+        .build();
+    let fill = PrimitiveStyle::with_fill(Rgb888::new(0, 255, 255));
+    let character_style = MonoTextStyle::new(&FONT_6X10, Rgb888::new(0, 255, 255));
+
+    let yoffset = 10;
+
+    // Draw a 3px wide outline around the display.
+    display
+        .bounding_box()
+        .into_styled(border_stroke)
+        .draw(&mut display)
+        .unwrap();
+
+    Rectangle::new(Point::new(52, yoffset), Size::new(16, 16))
+        .into_styled(fill)
+        .draw(&mut display)
+        .unwrap();
+
+    // Draw a triangle.
+    Triangle::new(
+        Point::new(16, 16 + yoffset),
+        Point::new(16 + 16, 16 + yoffset),
+        Point::new(16 + 8, yoffset),
+    )
+    .into_styled(thin_stroke)
+    .draw(&mut display)
+    .unwrap();
+
+    // Draw a filled square
+    Rectangle::new(Point::new(52, yoffset), Size::new(16, 16))
+        .into_styled(fill)
+        .draw(&mut display)
+        .unwrap();
+
+    // Draw a circle with a 3px wide stroke.
+    Circle::new(Point::new(88, yoffset), 17)
+        .into_styled(thick_stroke)
+        .draw(&mut display)
+        .unwrap();
+
+    // Draw centered text.
+    let text = "embedded-graphics";
+    Text::with_alignment(
+        text,
+        display.bounding_box().center() + Point::new(0, 15),
+        character_style,
+        Alignment::Center,
+    )
+    .draw(&mut display)
+    .unwrap();
+}

kernel/src/gdt.rs

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+use lazy_static::lazy_static;
+use x86_64::{
+    structures::{
+        gdt::{Descriptor, GlobalDescriptorTable, SegmentSelector},
+        tss::TaskStateSegment,
+    },
+    VirtAddr, registers::segmentation::{CS, Segment}, instructions::tables::load_tss,
+};
+
+pub const DOUBLE_FAULT_IST_INDEX: u16 = 0;
+
+pub fn init() {
+    GDT.0.load();
+    unsafe {
+        CS::set_reg(GDT.1.code);
+        load_tss(GDT.1.tss);
+        // TODO: properly handle this
+        x86_64::registers::segmentation::SS::set_reg(SegmentSelector::NULL);
+    }
+}
+
+struct Selectors {
+    code: SegmentSelector,
+    tss: SegmentSelector,
+}
+
+lazy_static! {
+    static ref GDT: (GlobalDescriptorTable, Selectors) = {
+        let mut gdt = GlobalDescriptorTable::new();
+        let code = gdt.add_entry(Descriptor::kernel_code_segment());
+        let tss = gdt.add_entry(Descriptor::tss_segment(&TSS));
+        (gdt, Selectors { code, tss })
+    };
+}
+
+lazy_static! {
+    static ref TSS: TaskStateSegment = {
+        let mut tss = TaskStateSegment::new();
+        tss.interrupt_stack_table[DOUBLE_FAULT_IST_INDEX as usize] = {
+            const STACK_SIZE: usize = 4096 * 5;
+            static mut STACK: [u8; STACK_SIZE] = [0; STACK_SIZE];
+
+            let stack_start = VirtAddr::from_ptr(unsafe { &STACK });
+            let stack_end = stack_start + STACK_SIZE;
+            stack_end
+        };
+        tss
+    };
+}

kernel/src/interrupts.rs

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+use crate::{gdt, print, println};
+use lazy_static::lazy_static;
+use pic8259::ChainedPics;
+use x86_64::structures::idt::{InterruptDescriptorTable, InterruptStackFrame};
+
+#[derive(Debug, Clone, Copy)]
+#[repr(u8)]
+pub enum InterruptIndex {
+    Timer = PIC_1_OFFSET,
+    Keyboard = PIC_1_OFFSET + 1,
+}
+
+impl InterruptIndex {
+    fn as_u8(self) -> u8 {
+        self as u8
+    }
+    fn as_usize(self) -> usize {
+        self as usize
+    }
+}
+
+pub fn init() {
+    IDT.load();
+    unsafe { PICS.lock().initialize() }
+    x86_64::instructions::interrupts::enable();
+}
+
+lazy_static! {
+    static ref IDT: InterruptDescriptorTable = {
+        let mut idt = InterruptDescriptorTable::new();
+        unsafe {
+            idt.double_fault
+                .set_handler_fn(double_fault)
+                .set_stack_index(gdt::DOUBLE_FAULT_IST_INDEX);
+        }
+        idt.breakpoint.set_handler_fn(breakpoint);
+        idt[InterruptIndex::Timer.as_usize()].set_handler_fn(timer);
+        idt[InterruptIndex::Keyboard.as_usize()].set_handler_fn(keyboard);
+        idt
+    };
+}
+
+extern "x86-interrupt" fn timer(_stack_frame: InterruptStackFrame) {
+    // print!(".");
+    unsafe {
+        PICS.lock()
+            .notify_end_of_interrupt(InterruptIndex::Timer as u8)
+    }
+}
+
+extern "x86-interrupt" fn breakpoint(_stack_frame: InterruptStackFrame) {
+    println!("POGGERS");
+}
+
+extern "x86-interrupt" fn double_fault(stack_frame: InterruptStackFrame, _error_code: u64) -> ! {
+    panic!("double fault exception: {:#?}", stack_frame);
+}
+
+extern "x86-interrupt" fn keyboard(_stack_frame: InterruptStackFrame) {
+    use pc_keyboard::{layouts, DecodedKey, HandleControl, Keyboard, ScancodeSet1};
+    use spin::Mutex;
+    use x86_64::instructions::port::Port;
+
+    lazy_static! {
+        static ref KEYBOARD: Mutex<Keyboard<layouts::Us104Key, ScancodeSet1>> =
+            Mutex::new(Keyboard::new(layouts::Us104Key, ScancodeSet1,
+                HandleControl::Ignore)
+            );
+    }
+
+    let mut keyboard = KEYBOARD.lock();
+    let mut port = Port::new(0x60);
+
+    let scancode: u8 = unsafe { port.read() };
+    if let Ok(Some(key_event)) = keyboard.add_byte(scancode) {
+        if let Some(key) = keyboard.process_keyevent(key_event) {
+            match key {
+                DecodedKey::Unicode(character) => print!("{}", character),
+                DecodedKey::RawKey(key) => print!("{:?}", key),
+            }
+        }
+    }
+
+    unsafe {
+        PICS.lock()
+            .notify_end_of_interrupt(InterruptIndex::Keyboard.as_u8());
+    }
+}
+
+pub const PIC_1_OFFSET: u8 = 32;
+pub const PIC_2_OFFSET: u8 = PIC_1_OFFSET + 8;
+
+pub static PICS: spin::Mutex<ChainedPics> =
+    spin::Mutex::new(unsafe { ChainedPics::new(PIC_1_OFFSET, PIC_2_OFFSET) });

kernel/src/lib.rs

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+#![no_std]
+#![feature(abi_x86_interrupt)]
+
+pub mod framebuffer;
+pub mod gdt;
+pub mod interrupts;
+pub mod qemu;
+pub mod log;
+
+pub fn init() {
+    gdt::init();
+    interrupts::init();
+}
+
+pub fn exit() -> ! {
+    qemu::exit();
+    hlt_loop()
+}
+
+pub fn hlt_loop() -> ! {
+    loop {
+        x86_64::instructions::hlt();
+    }
+}
+

kernel/src/log.rs

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+use core::fmt::Arguments;
+
+
+#[doc(hidden)]
+pub fn _log(args: Arguments<'_>) {
+    use core::fmt::Write;
+    interrupts::without_interrupts(|| {
+        UART.lock().write_fmt(args).unwrap();
+    })
+}
+
+#[macro_export]
+macro_rules! log {
+    ($($arg:tt)*) => ($crate::_log(format_args!($($arg)*)));
+}
+

kernel/src/main.rs

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+#![no_std]
+#![no_main]
+
+use kernel::{framebuffer, init, exit, println, hlt_loop};
+bootloader_api::entry_point!(kernel_main);
+
+fn kernel_main(boot_info: &'static mut bootloader_api::BootInfo) -> ! {
+    init();
+    if let Some(framebuffer) = boot_info.framebuffer.as_mut() {
+        framebuffer::draw_test(framebuffer);
+    }
+    for _ in 0..20000000 {}
+    hlt_loop();
+}
+
+#[panic_handler]
+fn panic(info: &core::panic::PanicInfo) -> ! {
+    println!("{}", info);
+    exit()
+}

kernel/src/qemu.rs

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+use core::fmt::Arguments;
+
+use spin::Mutex;
+use uart_16550::SerialPort;
+use x86_64::instructions::{interrupts, port::Port};
+
+pub static UART: Mutex<SerialPort> = Mutex::new(unsafe { SerialPort::new(0x3F8) });
+
+pub fn exit() {
+    unsafe {
+        let mut port = Port::new(0xf4);
+        port.write(0x10u32);
+    }
+}
+
+#[doc(hidden)]
+pub fn _print(args: Arguments<'_>) {
+    use core::fmt::Write;
+    interrupts::without_interrupts(|| {
+        UART.lock().write_fmt(args).unwrap();
+    })
+}
+
+#[macro_export]
+macro_rules! print {
+    ($($arg:tt)*) => ($crate::qemu::_print(format_args!($($arg)*)));
+}
+
+#[macro_export]
+macro_rules! println {
+    () => ($crate::print!("\n"));
+    ($($arg:tt)*) => ($crate::print!("{}\n", format_args!($($arg)*)));
+}