From 0d53d12133bd3f7dce0e3731a5bc7dc0c1facc9d Mon Sep 17 00:00:00 2001
From: Andrew Waterman <andrew@sifive.com>
Date: Fri, 14 Apr 2017 18:11:49 -0700
Subject: [PATCH] Fix illegal-instruction test when S-mode is not implemented

---
 isa/rv64mi/illegal.S | 24 ++++++++++++++----------
 1 file changed, 14 insertions(+), 10 deletions(-)

diff --git a/isa/rv64mi/illegal.S b/isa/rv64mi/illegal.S
index 30105e6..a1b445f 100644
--- a/isa/rv64mi/illegal.S
+++ b/isa/rv64mi/illegal.S
@@ -21,6 +21,15 @@ bad2:
   .word 0
   j fail
 
+  # Skip the rest of the test if S-mode is not present.
+  li t0, MSTATUS_MPP
+  csrc mstatus, t0
+  li t1, (MSTATUS_MPP & -MSTATUS_MPP) * PRV_S
+  csrs mstatus, t1
+  csrr t2, mstatus
+  and t2, t2, t0
+  bne t1, t2, pass
+
   # Test vectored interrupts if they are supported.
 test_vectored_interrupts:
   csrwi mip, MIP_SSIP
@@ -33,23 +42,18 @@ test_vectored_interrupts:
   csrsi mstatus, MSTATUS_MIE
 1:
   j 1b
-
 msip:
   csrw mtvec, s0
 
-  # Skip the rest of the test if S-mode is not present.
-  li t0, MSTATUS_MPP
-  csrc mstatus, t0
-  li t1, (MSTATUS_MPP & -MSTATUS_MPP) * PRV_S
-  csrs mstatus, t1
-  csrr t2, mstatus
-  and t2, t2, t0
-  bne t1, t2, pass
-
   # Delegate supervisor software interrupts so WFI won't stall.
   csrwi mideleg, MIP_SSIP
+  # Enter supervisor mode.
   la t0, 1f
   csrw mepc, t0
+  li t0, MSTATUS_MPP
+  csrc mstatus, t0
+  li t1, (MSTATUS_MPP & -MSTATUS_MPP) * PRV_S
+  csrs mstatus, t1
   mret
 
 1:
-- 
2.30.2