src/boot/boot.asm

@@ -163,9 +163,8 @@ p3_table:
 p2_table:
     resb 4096
 
-section .stack
 stack_bottom:
-    resb 0x800000
+    resb 4096
 stack_top:
 
 
@@ -185,5 +184,7 @@ long_mode_start:
     extern julios_main
     call julios_main
 
+    mov rax, 0x2f592f412f4b2f4f
+    mov qword [0xb8000], rax
 .loop:
     jmp .loop

src/gdt.rs

@@ -1,45 +0,0 @@
-use crate::println;
-use lazy_static::lazy_static;
-use x86_64::{VirtAddr, structures::tss::TaskStateSegment};
-use x86_64::structures::gdt::{GlobalDescriptorTable, Descriptor, SegmentSelector};
-use x86_64::instructions::{segmentation::{CS, Segment}, tables::load_tss};
-
-pub const DOUBLE_FAULT_IST_INDEX: u16 = 0;
-
-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
-    };
-}
-
-lazy_static! {
-    static ref GDT: (GlobalDescriptorTable, Selectors) = {
-        let mut gdt = GlobalDescriptorTable::new();
-        let code_selector = gdt.add_entry(Descriptor::kernel_code_segment());
-        let tss_selector = gdt.add_entry(Descriptor::tss_segment(&TSS));
-        (gdt, Selectors { code_selector, tss_selector })
-    };
-}
-
-pub fn init_gdt() {
-    println!("Loading GDT");
-    GDT.0.load();
-    unsafe {
-        CS::set_reg(GDT.1.code_selector);
-        load_tss(GDT.1.tss_selector);
-    }
-}
-
-struct Selectors {
-    code_selector: SegmentSelector,
-    tss_selector: SegmentSelector,
-}

src/interrupts.rs

@@ -1,36 +0,0 @@
-use crate::gdt;
-use crate::println;
-use crate::vga::{self, Color, ColorCode};
-use lazy_static::lazy_static;
-use x86_64::structures::idt::{InterruptDescriptorTable, InterruptStackFrame};
-
-lazy_static! {
-    static ref IDT: InterruptDescriptorTable = {
-        let mut idt = InterruptDescriptorTable::new();
-        idt.breakpoint.set_handler_fn(breakpoint_handler);
-        unsafe {
-            idt.double_fault.set_handler_fn(double_fault_handler)
-                .set_stack_index(gdt::DOUBLE_FAULT_IST_INDEX);
-        }
-        idt
-    };
-}
-
-pub fn init_idt() {
-    println!("Loading IDT");
-    IDT.load();
-}
-
-extern "x86-interrupt" fn breakpoint_handler(stack_frame: InterruptStackFrame) {
-    let color: vga::ColorCode = vga::get_color();
-    vga::change_color(ColorCode::new(Color::Pink, Color::Black));
-    println!("EXCEPTION: BREAKPOINT\n{:#?}", stack_frame);
-    vga::change_color(color);
-}
-
-extern "x86-interrupt" fn double_fault_handler(
-    stack_frame: InterruptStackFrame,
-    _error_code: u64,
-) -> ! {
-    panic!("EXCEPTION: DOUBLE FAULT\n{:#?}", stack_frame);
-}

src/lib.rs

@@ -1,39 +1,21 @@
 #![no_std]
 #![no_main]
-#![feature(abi_x86_interrupt)]
 
-mod gdt;
-mod interrupts;
 mod serial;
 mod vga;
-
 use core::panic::PanicInfo;
-use vga::{Color, ColorCode};
+use vga::Color;
 
 #[panic_handler]
 fn panic_handler(info: &PanicInfo) -> ! {
-    vga::change_color(ColorCode::new(Color::LightRed, Color::Black));
+    vga::change_color(Color::LightRed, Color::Black);
     println!("{}", info);
     loop {}
 }
 
-pub fn init() {
-    vga::change_color(ColorCode::new(Color::LightCyan, Color::Black));
-    println!("Starting init");
-    gdt::init_gdt();
-    interrupts::init_idt();
-    vga::change_color(ColorCode::new(Color::LightGreen, Color::Black));
-}
-
 #[no_mangle]
 pub extern "C" fn julios_main() -> ! {
-    init();
     println!("***JuliOS V0.1.0***");
-    fn stack_overflow() {
+    serial_println!("Hello serial");
-        stack_overflow(); // for each recursion, the return address is pushed
-    }
-
-    stack_overflow();
-
     panic!("Kernel end of flow");
 }

src/serial.rs

@@ -16,7 +16,7 @@ const ENABLE_TRANSMITTER: u8 = 0x1 << 1;
 const FIFO: u8 = 0x1;
 const TRIGGER_LVL_14: u8 = 0x3 << 6;
 const CLEAR_TRANSMIT_FIFO: u8 = 0x1 << 2;
-const CLEAR_RECEIVE_FIFO: u8 = 0x1 << 1;
+const CLEAR_REVEIVE_FIFO: u8 = 0x1 << 1;
 
 const NO_PARITY: u8 = 0x0;
 const EIGHT_BITS_LENGTH: u8 = 0x3;
@@ -118,7 +118,7 @@ impl SerialPort {
         unsafe {
             self.line_control.write(NO_PARITY | EIGHT_BITS_LENGTH);
             self.fifo_control
-                .write(FIFO | TRIGGER_LVL_14 | CLEAR_TRANSMIT_FIFO | CLEAR_RECEIVE_FIFO);
+                .write(FIFO | TRIGGER_LVL_14 | CLEAR_TRANSMIT_FIFO | CLEAR_REVEIVE_FIFO);
             self.interrupt_enable.write(ENABLE_TRANSMITTER);
         }
     }

src/vga.rs

@@ -30,11 +30,8 @@ pub fn _print(args: fmt::Arguments) {
     use core::fmt::Write;
     WRITER.lock().write_fmt(args).unwrap();
 }
-pub fn change_color(color: ColorCode) {
+pub fn change_color(fg: Color, bg: Color) {
-    WRITER.lock().change_color(color)
+    WRITER.lock().change_color(ColorCode::new(fg, bg))
-}
-pub fn get_color() -> ColorCode {
-    WRITER.lock().get_color()
 }
 
 #[allow(dead_code)]
@@ -61,10 +58,10 @@ pub enum Color {
 
 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
 #[repr(transparent)]
-pub struct ColorCode(u8);
+struct ColorCode(u8);
 
 impl ColorCode {
-    pub fn new(fg: Color, bg: Color) -> ColorCode {
+    fn new(fg: Color, bg: Color) -> ColorCode {
         ColorCode((bg as u8) << 4 | (fg as u8))
     }
 }
@@ -142,10 +139,6 @@ impl Writer {
     fn change_color(&mut self, color: ColorCode) {
         self.color_code = color;
     }
-
-    fn get_color(&mut self) -> ColorCode {
-        self.color_code
-    }
 }
 
 impl fmt::Write for Writer {