From c1786bfec884596a05ea249b47d56b0fb20da6a4 Mon Sep 17 00:00:00 2001
From: David Harris <david_harris@hmc.edu>
Date: Mon, 1 May 2023 08:14:19 -0700
Subject: [PATCH] IMMU exclude non word-sized accesses

---
 sim/coverage-exclusions-rv64gc.do | 7 +++++++
 src/mmu/mmu.sv                    | 2 +-
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/sim/coverage-exclusions-rv64gc.do b/sim/coverage-exclusions-rv64gc.do
index 88116aa3..ff9faeb5 100644
--- a/sim/coverage-exclusions-rv64gc.do
+++ b/sim/coverage-exclusions-rv64gc.do
@@ -201,6 +201,13 @@ coverage exclude -scope /dut/core/ifu/immu/immu/tlb/tlb/tlbcontrol -linerange $l
 set line [GetLineNum ../src/mmu/tlb/tlbcontrol.sv "~CAMHit & TLBAccess"] 
 coverage exclude -scope /dut/core/ifu/immu/immu/tlb/tlb/tlbcontrol -linerange $line-$line -item e 1 -fecexprrow 3
 
+# IMMU only makes word-sized accesses
+set line [GetLineNum ../src/mmu/mmu.sv "exclusion-tag: immu-wordaccess"] 
+set line2 [expr $line + 6 ]
+coverage exclude -scope /dut/core/ifu/immu/immu -linerange $line-$line2 -item e 1 -fecexprrow 4
+coverage exclude -scope /dut/core/ifu/immu/immu -linerange $line-$line2 -item b 1
+coverage exclude -scope /dut/core/ifu/immu/immu -linerange $line-$line2 -item s 1
+
 # Excluding reset and clear for impossible case in the wficountreg in privdec
 set line [GetLineNum ../src/generic/flop/floprc.sv "reset \\| clear"]
 coverage exclude -scope /dut/core/priv/priv/pmd/wfi/wficountreg -linerange $line-$line -item c 1 -feccondrow 2
diff --git a/src/mmu/mmu.sv b/src/mmu/mmu.sv
index ccbbfaf7..380787e6 100644
--- a/src/mmu/mmu.sv
+++ b/src/mmu/mmu.sv
@@ -128,7 +128,7 @@ module mmu #(parameter TLB_ENTRIES = 8, IMMU = 0) (
   assign StoreAmoAccessFaultM = (PMAStoreAmoAccessFaultM | PMPStoreAmoAccessFaultM) & ~TLBMiss;
 
   // Misaligned faults
-   always_comb
+   always_comb // exclusion-tag: immu-wordaccess
     case(Size[1:0]) 
       2'b00:  DataMisalignedM = 0;                 // lb, sb, lbu
       2'b01:  DataMisalignedM = VAdr[0];           // lh, sh, lhu