From 5b7cccbc4bd6ec4e912354f6001c5c15ce587b40 Mon Sep 17 00:00:00 2001
From: David Harris <david_harris@hmc.edu>
Date: Thu, 12 May 2022 23:33:22 +0000
Subject: [PATCH] Cause simplification

---
 pipelined/src/privileged/trap.sv | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pipelined/src/privileged/trap.sv b/pipelined/src/privileged/trap.sv
index fe2c7cf15..85f1d53e0 100644
--- a/pipelined/src/privileged/trap.sv
+++ b/pipelined/src/privileged/trap.sv
@@ -94,7 +94,7 @@ module trap (
     else if (IllegalInstrFaultM)       CauseM = 2;
     else if (InstrMisalignedFaultM)    CauseM = 0;
     else if (BreakpointFaultM)         CauseM = 3;
-    else if (EcallFaultM)              CauseM = {{(`XLEN-2){1'b0}}, PrivilegeModeW} + 8;
+    else if (EcallFaultM)              CauseM = {{(`XLEN-4){1'b0}}, {2'b10}, PrivilegeModeW};
     else if (LoadMisalignedFaultM)     CauseM = 4;
     else if (StoreAmoMisalignedFaultM) CauseM = 6;
     else if (LoadPageFaultM)           CauseM = 13;