Early message using SBI for logging & new board rcore_vmm_guest

kernel/src/arch/riscv/board/rcore_vmm_guest/mod.rs

@@ -0,0 +1,14 @@
+use crate::drivers::*;
+use crate::memory::phys_to_virt;
+use riscv::register::sie;
+
+/// Enable external interrupt
+pub unsafe fn init_external_interrupt() {
+    sie::set_sext();
+}
+
+pub fn init(dtb: usize) {
+    serial::uart16550::driver_init();
+    irq::plic::driver_init();
+    device_tree::init(dtb);
+}

kernel/src/arch/riscv/io.rs

@@ -1,11 +1,33 @@
+use crate::drivers::SerialDriver;
 use crate::drivers::SERIAL_DRIVERS;
+use alloc::sync::Arc;
 use core::fmt::{Arguments, Write};
+pub struct HeaplessWrite<T: AsRef<dyn SerialDriver>>(T);
+impl<T: AsRef<dyn SerialDriver>> core::fmt::Write for HeaplessWrite<T> {
+    fn write_str(&mut self, s: &str) -> core::fmt::Result {
+        self.0.as_ref().write(s.as_bytes());
+        Ok(())
+    }
+}
 
+pub struct HeaplessSBIWrite;
+impl core::fmt::Write for HeaplessSBIWrite {
+    fn write_str(&mut self, s: &str) -> core::fmt::Result {
+        for ch in s.as_bytes() {
+            super::sbi::console_putchar(*ch as usize);
+        }
+        Ok(())
+    }
+}
 pub fn putfmt(fmt: Arguments) {
     // output to serial
     let mut drivers = SERIAL_DRIVERS.write();
     if let Some(serial) = drivers.first_mut() {
-        serial.write(format!("{}", fmt).as_bytes());
+        HeaplessWrite(&serial).write_fmt(fmt).unwrap();
+    } else {
+        // might miss some early messages.
+        // no no no i don't accept it.
+        // note that we can't use heap here.
+        HeaplessSBIWrite.write_fmt(fmt).unwrap();
     }
-    // might miss some early messages, but it's okay
 }

kernel/src/arch/riscv/mod.rs

@@ -3,7 +3,10 @@ use trapframe;
 #[cfg(feature = "board_u540")]
 #[path = "board/u540/mod.rs"]
 pub mod board;
-#[cfg(not(feature = "board_u540"))]
+#[cfg(feature = "board_rcore_vmm_guest")]
+#[path = "board/rcore_vmm_guest/mod.rs"]
+pub mod board;
+#[cfg(not(any(feature = "board_u540", feature = "board_rcore_vmm_guest")))]
 #[path = "board/virt/mod.rs"]
 pub mod board;
 
@@ -16,7 +19,7 @@ pub mod io;
 pub mod memory;
 pub mod paging;
 pub mod rand;
-mod sbi;
+pub mod sbi;
 pub mod signal;
 pub mod syscall;
 pub mod timer;