feat(kernel/serial): add serial support

Makefile

@@ -0,0 +1,36 @@
+PROJECT_NAME := rkos
+TARGET := x86_64-unknown-none
+BUILD_MODE := release
+KERNEL_BIN := target/$(TARGET)/$(BUILD_MODE)/$(PROJECT_NAME)
+
+QEMU := qemu-system-x86_64
+QEMU_FLAGS := -machine q35 -kernel $(KERNEL_BIN) -serial stdio
+
+CARGO := cargo
+CARGO_FLAGS := --target $(TARGET)
+ifeq ($(BUILD_MODE), release)
+    CARGO_FLAGS += --release
+endif
+
+.PHONY: all build run clean check help
+
+all: build
+
+build:
+	@echo "Building $(PROJECT_NAME) in $(BUILD_MODE) mode..."
+	$(CARGO) build $(CARGO_FLAGS)
+clippy:
+	@echo "Clippy $(PROJECT_NAME) in $(BUILD_MODE) mode..."
+	$(CARGO) clippy $(CARGO_FLAGS) --bins --lib -- -D warnings
+run: build
+	@echo "Starting QEMU..."
+	@$(QEMU) $(QEMU_FLAGS)
+clean:
+	@echo "Cleaning project..."
+	@$(CARGO) clean
+	@rm -f build.log
+
+check:
+	@$(CARGO) check $(CARGO_FLAGS)
+
+.DEFAULT_GOAL := check

README.org

@@ -1,2 +1,14 @@
-* Rk
+* rkos
+[[Github Repo Starts][https://img.shields.io/github/stars/barrensea/rkos]]
+[[https://crates.io/crates/rkos][https://img.shields.io/crates/d/rkos.svg]]
+[[repo-size][https://img.shields.io/github/repo-size/barrensea/algori.svg]]
 
+** High Performance Rust Operation System Core in Rust!
+
+** Start
+
+Fist install the qemu, then
+
+#+begin_src shell
+  make run
+#+end_src

crates/rkos-arch/src/x86/head_64.S

@@ -1,6 +1,6 @@
 /*
     Bootstrapping x86_64 kernel
-    see also: https://wiki.osdev.org/Entering_Long_Mode
+    see also: https://wiki.osdev.org/Setting_Up_Long_Mode
 */
     /* prepare space for 4-level paging to entering long mode 
         .bss: | PML4 | PML3 | PML2 | Kernel_Stack(.bss.stack)|
@@ -54,7 +54,7 @@ gdt64_pointer:
     /* length of gdt64 minus 1 */
     .word 15    
     /* pointer to gdt64 */              
-    .quad gdt64 
+    .long gdt64 
 
     /* 
         multiboot header
@@ -151,4 +151,4 @@ long_mode_start:
     /* if _main returns, loop forever */
 .loop64:
     hlt
-    jmp .loop64
+    jmp .loop64

crates/rkos-arch/src/x86/mod.rs

@@ -1 +1 @@
-
+pub mod serial;

crates/rkos-arch/src/x86/serial.rs

@@ -0,0 +1,65 @@
+// see also: https://wiki.osdev.org/Serial_Ports
+use core::arch::asm;
+use core::fmt;
+
+const COM1: u16 = 0x3F8;
+
+/// Write a byte to the serial port
+unsafe fn outb(port: u16, val: u8) {
+    unsafe {
+        asm!("out dx, al", in("dx") port, in("al") val, options(nomem, nostack, preserves_flags));
+    }
+}
+
+/// Read a byte from the serial port
+unsafe fn inb(port: u16) -> u8 {
+    let mut val: u8;
+    unsafe {
+        asm!("in al, dx", out("al") val, in("dx") port, options(nomem, nostack, preserves_flags));
+    }
+    val
+}
+
+pub struct SerialPort;
+
+impl SerialPort {
+    /// Initialize the standard COM1 serial port
+    pub fn init() {
+        unsafe {
+            outb(COM1 + 1, 0x00); // Disable all interrupts
+            outb(COM1 + 3, 0x80); // Enable DLAB (set baud rate divisor)
+            outb(COM1, 0x03); // Set divisor to 3 (lo byte) 38400 baud
+            outb(COM1 + 1, 0x00); //                  (hi byte)
+            outb(COM1 + 3, 0x03); // 8 bits, no parity, one stop bit
+            outb(COM1 + 2, 0xC7); // Enable FIFO, clear them, with 14-byte threshold
+            outb(COM1 + 4, 0x0B); // IRQs enabled, RTS/DSR set
+        }
+    }
+
+    /// Check if transmit buffer is empty
+    fn is_transmit_empty() -> bool {
+        unsafe { inb(COM1 + 5) & 0x20 != 0 }
+    }
+
+    /// Write a byte to the serial port
+    pub fn write_byte(b: u8) {
+        while !Self::is_transmit_empty() {}
+        unsafe {
+            outb(COM1, b);
+        }
+    }
+}
+
+impl fmt::Write for SerialPort {
+    fn write_str(&mut self, s: &str) -> fmt::Result {
+        for byte in s.bytes() {
+            SerialPort::write_byte(byte);
+        }
+        Ok(())
+    }
+}
+
+pub fn _print(args: fmt::Arguments) {
+    let mut serial = SerialPort;
+    let _ = fmt::Write::write_fmt(&mut serial, args);
+}

crates/rkos/Cargo.toml

@@ -10,7 +10,7 @@ description.workspace = true
 rust-version.workspace = true
 
 [dependencies]
-
+rkos-arch = { path = "../rkos-arch" }
 
 # [lints]
 # workspace = true

crates/rkos/src/console.rs

@@ -0,0 +1,18 @@
+use core::fmt;
+
+#[macro_export]
+macro_rules! print {
+    ($($arg:tt)*) => ($crate::console::_print(format_args!($($arg)*)));
+}
+
+#[macro_export]
+macro_rules! println {
+    () => ($crate::print!("\n"));
+    ($fmt:expr) => ($crate::print!(concat!($fmt, "\n")));
+    ($fmt:expr, $($arg:tt)*) => ($crate::print!(concat!($fmt, "\n"), $($arg)*));
+}
+
+#[doc(hidden)]
+pub fn _print(args: fmt::Arguments) {
+    rkos_arch::x86::serial::_print(args);
+}

crates/rkos/src/main.rs

@@ -7,20 +7,15 @@ use core::panic::PanicInfo;
 #[cfg(target_arch = "x86_64")]
 global_asm!(include_str!("../../rkos-arch/src/x86/head_64.S"));
 
+#[macro_use]
+pub mod console;
+
 #[unsafe(no_mangle)]
 pub extern "C" fn _main() {
-    // VGA_BASE: 0xb8000
-    let vga_buffer = 0xb8000 as *mut u8;
-
-    let text = b"[OK] Barrensea rkos has conquered 64-bit Long Mode!!!";
-    let color_byte = 0x0a;
+    rkos_arch::x86::serial::SerialPort::init();
 
-    for (i, &byte) in text.iter().enumerate() {
-        unsafe {
-            *vga_buffer.add(i * 2) = byte;
-            *vga_buffer.add(i * 2 + 1) = color_byte;
-        }
-    }
+    println!("[OK] Barrensea rkos has conquered 64-bit Long Mode!!!");
+    println!("Hello from rkos serial output!");
 
     unsafe extern "C" {
         fn stext();