From 03a7e2f0b95752a2d056c4000fdbb3fe189885f2 Mon Sep 17 00:00:00 2001
From: Yu Chen <yuchen@mail.tsinghua.edu.cn>
Date: Tue, 21 Jun 2022 23:45:12 +0800
Subject: [PATCH] sbi spec uses a6, a7 as sbicall id, so we need to set a6 to 0

---
 os/src/sbi.rs | 1 +
 1 file changed, 1 insertion(+)

diff --git a/os/src/sbi.rs b/os/src/sbi.rs
index 2e2804b2..cfd59a07 100644
--- a/os/src/sbi.rs
+++ b/os/src/sbi.rs
@@ -17,6 +17,7 @@ fn sbi_call(which: usize, arg0: usize, arg1: usize, arg2: usize) -> usize {
     let mut ret;
     unsafe {
         asm!(
+            "li x16, 0",
             "ecall",
             inlateout("x10") arg0 => ret,
             in("x11") arg1,