From a9f3182de3aabbb43076f01a7c8ce3c1a1dd37e6 Mon Sep 17 00:00:00 2001
From: Xiao Xiong <xiao@mathai.cloud>
Date: Fri, 21 Aug 2026 15:24:31 -0400
Subject: [PATCH] more stuff!

---
 .gitignore             |  1 +
 src/arch/x86_64/cpu.rs | 13 +++++++++++
 src/arch/x86_64/mod.rs |  6 ++++-
 src/driver/mod.rs      |  1 +
 src/driver/serial.rs   | 52 ++++++++++++++++++++++++++++++++++++++++++
 src/kernel/init.rs     |  5 +++-
 src/kernel/log.rs      | 36 +++++++++++++++++++++++++++++
 src/kernel/mod.rs      |  3 ++-
 src/main.rs            |  3 ++-
 9 files changed, 116 insertions(+), 4 deletions(-)
 create mode 100644 src/arch/x86_64/cpu.rs
 create mode 100644 src/driver/mod.rs
 create mode 100644 src/driver/serial.rs
 create mode 100644 src/kernel/log.rs

diff --git a/.gitignore b/.gitignore
index ea8c4bf..334c109 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1 +1,2 @@
 /target
+/tests
\ No newline at end of file
diff --git a/src/arch/x86_64/cpu.rs b/src/arch/x86_64/cpu.rs
new file mode 100644
index 0000000..e766474
--- /dev/null
+++ b/src/arch/x86_64/cpu.rs
@@ -0,0 +1,13 @@
+use core::arch::x86_64::__cpuid;
+
+pub fn init() {
+    let cpuid = unsafe { __cpuid(0) };
+
+    let mut vendor = [0u8;12];
+
+    vendor[0..4].copy_from_slice(&cpuid.ebx.to_le_bytes());
+    vendor[4..8].copy_from_slice(&cpuid.edx.to_le_bytes());
+    vendor[8..12].copy_from_slice(&cpuid.ecx.to_le_bytes());
+
+    crate::kprintln!("CPU Vendor: {}", core::str::from_utf8(&vendor).unwrap_or("Unknown"));
+}
\ No newline at end of file
diff --git a/src/arch/x86_64/mod.rs b/src/arch/x86_64/mod.rs
index ab0c014..61b0cf1 100644
--- a/src/arch/x86_64/mod.rs
+++ b/src/arch/x86_64/mod.rs
@@ -1 +1,5 @@
-//
\ No newline at end of file
+pub mod cpu;
+
+pub fn init() {
+    cpu::init();
+}
\ No newline at end of file
diff --git a/src/driver/mod.rs b/src/driver/mod.rs
new file mode 100644
index 0000000..85b9b05
--- /dev/null
+++ b/src/driver/mod.rs
@@ -0,0 +1 @@
+pub mod serial;
\ No newline at end of file
diff --git a/src/driver/serial.rs b/src/driver/serial.rs
new file mode 100644
index 0000000..27c2d64
--- /dev/null
+++ b/src/driver/serial.rs
@@ -0,0 +1,52 @@
+use core::arch::asm;
+
+const SERIAL_COM1: u16 = 0x3F8;
+
+pub unsafe fn init() {
+    outb(SERIAL_COM1 + 1, 0x00); // Disable interrupts  
+
+    outb(SERIAL_COM1 + 3, 0x80);
+
+    outb(SERIAL_COM1, 0x03); // 38400 baud (divisor = 3)
+    outb(SERIAL_COM1 + 1, 0x00);
+
+    outb(SERIAL_COM1 + 3, 0x03);
+
+    outb(SERIAL_COM1 + 2, 0xC7);
+
+    outb(SERIAL_COM1 + 4, 0x0B);
+}
+
+pub unsafe fn write_byte(byte: u8) {
+    while (inb(SERIAL_COM1 + 5) & 0x20) == 0 {}
+    outb(SERIAL_COM1, byte);
+}
+
+pub unsafe fn write_bytes(bytes: &[u8]) {
+    for &byte in bytes {
+        write_byte(byte);
+    }
+}
+
+pub unsafe fn write_str(string: &str) {
+    write_bytes(string.as_bytes());
+}
+
+unsafe fn outb(port: u16, value: u8) {
+    asm!(
+        "out dx, al",
+        in("dx") port,
+        in("al") value,
+        options(nostack, nomem, preserves_flags)
+    );
+}
+
+unsafe fn inb(port: u16) -> u8 {
+    let value: u8;
+
+    unsafe {
+        asm!("in al, dx",in("dx") port,out("al") value,options(nostack, nomem, preserves_flags));
+    }
+    
+    value
+}
\ No newline at end of file
diff --git a/src/kernel/init.rs b/src/kernel/init.rs
index b5673eb..817d708 100644
--- a/src/kernel/init.rs
+++ b/src/kernel/init.rs
@@ -1,3 +1,6 @@
 pub fn init() {
-    // something something init kernel
+    unsafe {
+        crate::driver::serial::init();
+    }
+    crate::arch::x86_64::init();
 }
\ No newline at end of file
diff --git a/src/kernel/log.rs b/src/kernel/log.rs
new file mode 100644
index 0000000..5956230
--- /dev/null
+++ b/src/kernel/log.rs
@@ -0,0 +1,36 @@
+use core::fmt::{self, Write};
+
+struct Logger;
+
+impl Write for Logger {
+    fn write_str(&mut self, string: &str) -> fmt::Result {
+        unsafe {
+            crate::driver::serial::write_str(string);
+        }
+
+        Ok(())
+    }
+}
+
+pub fn print(args: fmt::Arguments) {
+    let mut logger = Logger;
+    logger.write_fmt(args).ok();
+}
+
+#[macro_export]
+macro_rules! kprint {
+    ($($arg:tt)*) => {
+        $crate::kernel::log::print(core::format_args!($($arg)*))
+    };
+}
+
+#[macro_export]
+macro_rules! kprintln {
+    () => {
+        $crate::kprint!("\r\n")
+    };
+
+    ($($arg:tt)*) => {
+        $crate::kprint!("{}\r\n", core::format_args!($($arg)*))
+    };
+}
\ No newline at end of file
diff --git a/src/kernel/mod.rs b/src/kernel/mod.rs
index 639a6c5..300d111 100644
--- a/src/kernel/mod.rs
+++ b/src/kernel/mod.rs
@@ -1 +1,2 @@
-pub mod init;
\ No newline at end of file
+pub mod init;
+pub mod log;
\ No newline at end of file
diff --git a/src/main.rs b/src/main.rs
index 4e17f08..c89bb4b 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -2,12 +2,13 @@
 #![no_main]
 
 mod arch;
+mod driver;
 mod kernel;
 
 #[unsafe(no_mangle)]
 pub extern "C" fn _start() -> ! {
     kernel::init::init();
-    
+
     loop {}
 }