From 4fc7516694ecf1319b39b75d7f78bcd9b6b43221 Mon Sep 17 00:00:00 2001
From: Rose Thompson <rose@rosethompson.net>
Date: Mon, 30 Sep 2024 16:39:59 -0500
Subject: [PATCH] Created test to show TLB misses supress misaligned faults.
 Test first checks cached accesses which should not cause misaligned faults
 and then uses PBMT to disable cachablity.

---
 tests/coverage/tlbMisaligned.S | 153 +++++++++++++++++++++++++++++++++
 1 file changed, 153 insertions(+)
 create mode 100644 tests/coverage/tlbMisaligned.S

diff --git a/tests/coverage/tlbMisaligned.S b/tests/coverage/tlbMisaligned.S
new file mode 100644
index 000000000..12249c8b5
--- /dev/null
+++ b/tests/coverage/tlbMisaligned.S
@@ -0,0 +1,153 @@
+///////////////////////////////////////////
+// tlbGP.S
+//
+// Written: mmendozamanriquez@hmc.edu 4 April 2023
+//          nlimpert@hmc.edu
+//
+// Purpose: Create Page tables and access gigapages
+//
+// A component of the CORE-V-WALLY configurable RISC-V project.
+// https://github.com/openhwgroup/cvw
+// 
+// Copyright (C) 2021-23 Harvey Mudd College & Oklahoma State University
+//
+// SPDX-License-Identifier: Apache-2.0 WITH SHL-2.1
+//
+// Licensed under the Solderpad Hardware License v 2.1 (the “License”); you may not use this file 
+// except in compliance with the License, or, at your option, the Apache License version 2.0. You 
+// may obtain a copy of the License at
+//
+// https://solderpad.org/licenses/SHL-2.1/
+//
+// Unless required by applicable law or agreed to in writing, any work distributed under the 
+// License is distributed on an “AS IS” BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, 
+// either express or implied. See the License for the specific language governing permissions 
+// and limitations under the License.
+////////////////////////////////////////////////////////////////////////////////////////////////
+
+// load code to initalize stack, handle interrupts, terminate
+
+#include "WALLY-init-lib.h"
+
+# run-elf.bash find this in project description
+main:
+    li t5, 0x1
+    slli t5, t5, 62
+    ori t5, t5, 0xF0
+    csrs menvcfg, t5  # menvcfg.PBMTE = 1, CBZE, CBCFE, CBIE all 1
+
+    # Page table root address at 0x80010000
+    li t5, 0x9000000000080010
+    csrw satp, t5
+
+    # sfence.vma x0, x0
+
+    # switch to supervisor mode
+    li a0, 1   
+    ecall
+    li t5, 0
+    li t2, 0x1000
+    li t0, 0x1000 // go to first gigapage 
+    li t4, 0x40000000 // put this outside the loop.
+
+    lw t1, 1(t0) # load a misaligned aligned cached address
+    li t1, 0x00008067 #load in jalr
+    add t0, t0, t2 # go to the next page
+    sw t1, 1(t0) # store to another misaligned cached address.
+
+    add t0, t0, t2 # go to the next page
+    lw t1, 1(t0) # load a misaligned aligned uncached address should fault
+    add t0, t0, t2 # go to the next page
+    sw t1, 1(t0) # store to another misaligned uncached address should falt.
+        
+    fence.I
+
+finished:
+    j done
+
+.data
+
+.align 16
+# Page table situated at 0x80010000
+pagetable: 
+    .8byte 0x200044C1 
+
+.align 12
+    .8byte 0x00000000200048C1
+    .8byte 0x00000000200048C1
+    .8byte 0x00000000200048C1
+    
+
+.align 12
+    .8byte 0x0000000020004CC1
+    //.8byte 0x00000200800CF// ADD IN THE MEGAPAGE should 3 nibbles of zeros be removed?
+
+.align 12
+    #80000000
+    .8byte 0x200000CF
+    .8byte 0x200004CF  # first page
+    .8byte 0x200008CF  # second page
+    .8byte 0x2000000020000CCF  # 3rd page
+
+    .8byte 0x20000000200010CF  # 4th page
+    .8byte 0x200014CF
+    .8byte 0x200018CF
+    .8byte 0x20001CCF
+
+    .8byte 0x200020CF
+    .8byte 0x200024CF
+    .8byte 0x200028CF
+    .8byte 0x20002CCF
+
+    .8byte 0x200030CF
+    .8byte 0x200034CF
+    .8byte 0x200038CF
+    .8byte 0x20003CCF
+
+    .8byte 0x200040CF
+    .8byte 0x200044CF
+    .8byte 0x200048CF
+    .8byte 0x20004CCF
+
+    .8byte 0x200050CF
+    .8byte 0x200054CF
+    .8byte 0x200058CF
+    .8byte 0x20005CCF
+
+    .8byte 0x200060CF
+    .8byte 0x200064CF
+    .8byte 0x200068CF
+    .8byte 0x20006CCF
+
+    .8byte 0x200070CF
+    .8byte 0x200074CF
+    .8byte 0x200078CF
+    .8byte 0x20007CCF
+    
+    .8byte 0x200080CF
+    .8byte 0x200084CF
+    .8byte 0x200088CF
+    .8byte 0x20008CCF
+
+    .8byte 0x200090CF
+    .8byte 0x200094CF
+    .8byte 0x200098CF
+    .8byte 0x20009CCF
+
+    .8byte 0x2000A0CF
+    .8byte 0x2000A4CF
+    .8byte 0x2000A8CF
+    .8byte 0x2000ACCF
+
+    .8byte 0x2000B0CF
+    .8byte 0x2000B4CF
+    .8byte 0x2000B8CF
+    .8byte 0x2000BCCF
+
+    .8byte 0x2000C0CF
+    .8byte 0x2000C4CF
+    .8byte 0x2000C8CF
+    .8byte 0x2000CCCF
+
+    .8byte 0x2000D0CF
+    .8byte 0x2000D4CF