ARM: Add serial console logging

kernel/src/arch/aarch64/logging.rs

@@ -0,0 +1,23 @@
+use {core::fmt::Write, spin::Mutex};
+
+const SERIAL_CONSOLE: Mutex<SerialConsole> = Mutex::new(SerialConsole {
+    uart: 0x09000000 as *mut u8,
+});
+
+struct SerialConsole {
+    uart: *mut u8,
+}
+
+impl core::fmt::Write for SerialConsole {
+    fn write_str(&mut self, s: &str) -> core::fmt::Result {
+        for c in s.chars() {
+            unsafe { *self.uart = c as u8 }
+        }
+
+        Ok(())
+    }
+}
+
+pub fn log(args: core::fmt::Arguments<'_>) -> core::fmt::Result {
+    SERIAL_CONSOLE.lock().write_fmt(args)
+}

kernel/src/arch/aarch64/mod.rs

@@ -1,9 +1,15 @@
 use {core::arch::asm, limine::FramebufferRequest};
 
+pub mod logging;
+pub use logging::log;
+
 pub const PAGE_SIZE: usize = 4096;
 
 #[no_mangle]
 unsafe extern "C" fn _kernel_start() -> ! {
+    crate::logger::init().expect("failed to set logger");
+    log::info!("Initialising AKern {}", crate::VERSION);
+
     static FB_REQ: FramebufferRequest = FramebufferRequest::new(0);
     let fb1 = &FB_REQ.get_response().get().unwrap().framebuffers()[0];
 
@@ -26,7 +32,3 @@ pub fn spin_loop() -> ! {
 pub fn hardware_random_u64() -> u64 {
     0
 }
-
-pub fn log(_args: core::fmt::Arguments<'_>) -> core::fmt::Result {
-    panic!()
-}

kernel/src/arch/x86_64/logging.rs

@@ -19,9 +19,7 @@ pub fn init() {
 pub fn log(args: core::fmt::Arguments<'_>) -> core::fmt::Result {
     x86_64::instructions::interrupts::without_interrupts(|| {
         // TERMINAL_LOGGER.lock().write_fmt(args)?;
-        let mut sc = SERIAL_CONSOLE.lock();
-        sc.write_fmt(args)?;
-        Ok(())
+        SERIAL_CONSOLE.lock().write_fmt(args)
     })
 }