Merge pull request #45 from woshiluo/patch-1

fix(prototyper): set SCOUNTEREN to allow

prototyper/src/main.rs

@@ -89,6 +89,7 @@ extern "C" fn rust_main(_hart_id: usize, opaque: usize, nonstandard_a2: usize) {
         asm!("csrw mideleg,    {}", in(reg) !0);
         asm!("csrw medeleg,    {}", in(reg) !0);
         asm!("csrw mcounteren, {}", in(reg) !0);
+        asm!("csrw scounteren, {}", in(reg) !0);
         use riscv::register::{medeleg, mtvec};
         // Keep supervisor environment calls and illegal instructions in M-mode.
         medeleg::clear_supervisor_env_call();