Now, ch9-log can run

os/Cargo.toml

@@ -20,6 +20,6 @@ virtio-drivers = { git = "https://github.com/rcore-os/virtio-drivers" }
 # easy-fs = { path = "../easy-fs" }
 #log = "0.4"
 spin = "0.7.0"
-# [features]
-# board_qemu = []
-# board_k210 = []
+[features]
+board_qemu = []
+board_k210 = []

os/src/board/mod.rs

@@ -1,3 +1,6 @@
+mod qemu;
+pub use qemu::*;
+
 pub const CLOCK_FREQ: usize = 12500000;
 
 pub const MMIO: &[(usize, usize)] = &[

os/src/board/qemu.rs

@@ -19,6 +19,7 @@ use crate::drivers::plic::{IntrTargetPriority, PLIC};
 
 pub fn device_init() {
     use riscv::register::sie;
+    
     kprintln!("[KERN] board::qemu::device_init() begin");
     let mut plic = unsafe { PLIC::new(VIRT_PLIC) };
     let hart_id: usize = 0;

os/src/main.rs

@@ -12,8 +12,8 @@ extern crate bitflags;
 // #[path = "boards/k210.rs"]
 // mod board;
 // #[cfg(not(any(feature = "board_k210")))]
-// #[path = "boards/qemu.rs"]
-
+// #[path = "board/qemu.rs"]
+// mod board::qemu;
 
 #[macro_use]
 mod console;