diff --git a/test/vpnor/Makefile.am.include b/test/vpnor/Makefile.am.include
index c2ebb1f..b71e8e0 100644
--- a/test/vpnor/Makefile.am.include
+++ b/test/vpnor/Makefile.am.include
@@ -25,15 +25,15 @@
 test_vpnor_create_read_window_vpnor_LDFLAGS = $(OESDK_TESTCASE_FLAGS)
 test_vpnor_create_read_window_vpnor_LDADD = $(VPNOR_LDADD)
 
-test_vpnor_write_flash_vpnor_SOURCES = \
+test_vpnor_write_patch_SOURCES = \
 	$(TEST_MBOX_VPNOR_SRCS) \
 	mboxd_pnor_partition_table.cpp \
 	mboxd_flash_virtual.cpp \
 	mtd.c \
 	pnor_partition.cpp \
-	%reldir%/write_flash_vpnor.cpp
-test_vpnor_write_flash_vpnor_LDFLAGS = $(OESDK_TESTCASE_FLAGS)
-test_vpnor_write_flash_vpnor_LDADD = $(VPNOR_LDADD)
+	%reldir%/write_patch.cpp
+test_vpnor_write_patch_LDFLAGS = $(OESDK_TESTCASE_FLAGS)
+test_vpnor_write_patch_LDADD = $(VPNOR_LDADD)
 
 test_vpnor_write_prsv_SOURCES = \
 	$(TEST_MBOX_VPNOR_SRCS) \
@@ -69,8 +69,8 @@
 check_PROGRAMS += \
 	%reldir%/create_pnor_partition_table \
 	%reldir%/create_read_window_vpnor \
-	%reldir%/write_flash_vpnor \
 	%reldir%/write_prsv \
 	%reldir%/write_ro \
-	%reldir%/write_rw
+	%reldir%/write_rw \
+	%reldir%/write_patch
 endif
diff --git a/test/vpnor/write_flash_vpnor.cpp b/test/vpnor/write_flash_vpnor.cpp
deleted file mode 100644
index 5bb6f51..0000000
--- a/test/vpnor/write_flash_vpnor.cpp
+++ /dev/null
@@ -1,174 +0,0 @@
-/*
- * MBox Daemon Test File
- *
- * Copyright 2017 IBM
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * 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.
- *
- */
-
-extern "C" {
-#include "config.h"
-#include "common.h"
-#include "mboxd_flash.h"
-#include "mboxd_pnor_partition_table.h"
-#include "mbox.h"
-#include "test/tmpf.h"
-}
-
-#include <assert.h>
-#include <unistd.h>
-
-#include <fstream>
-#include <experimental/filesystem>
-
-#include <sys/mman.h>
-#include <sys/syslog.h>
-#include <sys/ioctl.h>
-#include <fcntl.h>
-
-#include "test/vpnor/tmpd.hpp"
-
-uint8_t data[8] = {0xa0, 0xa1, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7};
-
-#define BLOCK_SIZE 4096
-#define OFFSET BLOCK_SIZE
-#define MEM_SIZE (BLOCK_SIZE * 2)
-#define DATA_SIZE sizeof(data)
-#define BLOCK_SIZE_SHIFT 12
-
-const std::string toc[] = {
-    "partition01=TEST1,00001000,00001400,ECC,READONLY",
-    "partition02=TEST2,00002000,00002008,ECC,READWRITE",
-    "partition03=TEST3,00003000,00003400,ECC,PRESERVED",
-};
-
-std::vector<std::string> partitions = {"TEST1", "TEST2", "TEST3"};
-
-namespace test = openpower::virtual_pnor::test;
-
-void init(struct mbox_context* ctx, test::VpnorRoot& root)
-{
-    namespace fs = std::experimental::filesystem;
-    using namespace std::string_literals;
-
-    // create the partition files in the ro directory
-    for (auto partition : partitions)
-    {
-        root.write(partition, data, sizeof(data));
-    }
-
-    // copy partition2 file from ro to rw
-    assert(fs::copy_file(root.ro() / "TEST2", root.rw() / "TEST2"));
-
-    mbox_vlog = &mbox_log_console;
-    verbosity = (verbose)2;
-
-    // setting context parameters
-    ctx->erase_size_shift = BLOCK_SIZE_SHIFT;
-    ctx->block_size_shift = BLOCK_SIZE_SHIFT;
-    ctx->flash_bmap = reinterpret_cast<uint8_t*>(
-        calloc(MEM_SIZE >> ctx->erase_size_shift, sizeof(*ctx->flash_bmap)));
-}
-
-int main(void)
-{
-    namespace fs = std::experimental::filesystem;
-
-    int rc{};
-    int fd;
-    void* map;
-    char src[DATA_SIZE]{0};
-    struct mbox_context context;
-    struct mbox_context* ctx = &context;
-    memset(ctx, 0, sizeof(mbox_context));
-
-    test::VpnorRoot root(ctx, toc, BLOCK_SIZE);
-
-    // Initialize the context before running the test case.
-    init(ctx, root);
-
-    // create the partition table
-    vpnor_create_partition_table_from_path(ctx, root.ro().c_str());
-
-    // write beyond the partition length as the partition
-    // file length is 8 byte(TEST2).
-    rc = write_flash(ctx, (OFFSET * 2 + 3), src, sizeof(src) + 20);
-    assert(rc == -1);
-
-    memset(src, 0xcc, sizeof(src));
-    rc = write_flash(ctx, (OFFSET * 2), src, sizeof(src));
-    assert(rc == 0);
-    fd = open((root.rw() / "TEST2").c_str(), O_RDONLY);
-    map = mmap(NULL, MEM_SIZE, PROT_READ, MAP_PRIVATE, fd, 0);
-    assert(map != MAP_FAILED);
-    rc = memcmp(src, map, sizeof(src));
-    assert(rc == 0);
-
-    src[0] = 0xff;
-    rc = write_flash(ctx, (OFFSET * 2), src, 1);
-    assert(rc == 0);
-    rc = memcmp(src, map, sizeof(src));
-    assert(rc == 0);
-
-    src[1] = 0xff;
-    rc = write_flash(ctx, (OFFSET * 2) + 1, &src[1], 1);
-    assert(rc == 0);
-    rc = memcmp(src, map, sizeof(src));
-    assert(rc == 0);
-
-    src[2] = 0xff;
-    rc = write_flash(ctx, (OFFSET * 2) + 2, &src[2], 1);
-    assert(rc == 0);
-    rc = memcmp(src, map, sizeof(src));
-    assert(rc == 0);
-
-    munmap(map, MEM_SIZE);
-    close(fd);
-
-    // START Test patch location - Patch dir has preference over other locations
-    // Copy partition2 file from ro to patch to simulate a patch file that is
-    // different from the one in rw (partition2 in rw was modified with the
-    // previous write test)
-    fs::path patch = root.patch() / "TEST2";
-    assert(fs::copy_file(root.ro() / "TEST2", patch));
-
-    // Write arbitrary data
-    char srcPatch[DATA_SIZE]{0};
-    memset(srcPatch, 0x33, sizeof(srcPatch));
-    rc = write_flash(ctx, (OFFSET * 2), srcPatch, sizeof(srcPatch));
-    assert(rc == 0);
-
-    // Check that partition file in RW location still contains the original data
-    fd = open((root.rw() / "TEST2").c_str(), O_RDONLY);
-    map = mmap(NULL, MEM_SIZE, PROT_READ, MAP_PRIVATE, fd, 0);
-    assert(map != MAP_FAILED);
-    rc = memcmp(src, map, sizeof(src));
-    assert(rc == 0);
-    munmap(map, MEM_SIZE);
-    close(fd);
-
-    // Check that partition file in PATCH location was written with the new data
-    fd = open(patch.c_str(), O_RDONLY);
-    map = mmap(NULL, MEM_SIZE, PROT_READ, MAP_PRIVATE, fd, 0);
-    assert(map != MAP_FAILED);
-    rc = memcmp(srcPatch, map, sizeof(srcPatch));
-    assert(rc == 0);
-    munmap(map, MEM_SIZE);
-    close(fd);
-
-    destroy_vpnor(ctx);
-    free(ctx->flash_bmap);
-
-    return rc;
-}
diff --git a/test/vpnor/write_patch.cpp b/test/vpnor/write_patch.cpp
new file mode 100644
index 0000000..b0d5fa7
--- /dev/null
+++ b/test/vpnor/write_patch.cpp
@@ -0,0 +1,82 @@
+// SPDX-License-Identifier: Apache-2.0
+// Copyright (C) 2018 IBM Corp.
+
+#include <assert.h>
+#include <experimental/filesystem>
+#include <fcntl.h>
+#include <sys/ioctl.h>
+#include <sys/mman.h>
+#include <sys/syslog.h>
+#include <unistd.h>
+
+#include "config.h"
+#include "common.h"
+#include "mbox.h"
+#include "mboxd_flash.h"
+
+#include "test/vpnor/tmpd.hpp"
+
+static constexpr auto BLOCK_SIZE = 0x1000;
+static constexpr auto DATA_SIZE = 8;
+
+const uint8_t data[DATA_SIZE] = {0xa0, 0xa1, 0xa2, 0xa3,
+                                 0xa4, 0xa5, 0xa6, 0xa7};
+
+const std::string toc[] = {
+    "partition01=TEST1,00001000,00002000,80,ECC,READWRITE",
+};
+
+int main(void)
+{
+    namespace fs = std::experimental::filesystem;
+    namespace test = openpower::virtual_pnor::test;
+
+    struct mbox_context _ctx, *ctx = &_ctx;
+    char src[DATA_SIZE]{0};
+    void *map;
+    int rc;
+    int fd;
+
+    /* Setup */
+    memset(ctx, 0, sizeof(mbox_context));
+
+    mbox_vlog = &mbox_log_console;
+    verbosity = (verbose)2;
+
+    test::VpnorRoot root(ctx, toc, BLOCK_SIZE);
+    root.write("TEST1", data, sizeof(data));
+    /* write_flash doesn't copy the file for us */
+    assert(fs::copy_file(root.ro() / "TEST1", root.rw() / "TEST1"));
+    fs::path patch = root.patch() / "TEST1";
+    assert(fs::copy_file(root.ro() / "TEST1", patch));
+
+    vpnor_create_partition_table_from_path(ctx, root.ro().c_str());
+
+    /* Test */
+    memset(src, 0x33, sizeof(src));
+    rc = write_flash(ctx, 0x1000, src, sizeof(src));
+    assert(rc == 0);
+
+    /* Check that RW file is unmodified after the patch write */
+    fd = open((root.rw() / "TEST1").c_str(), O_RDONLY);
+    map = mmap(NULL, sizeof(src), PROT_READ, MAP_SHARED, fd, 0);
+    assert(map != MAP_FAILED);
+    rc = memcmp(data, map, sizeof(src));
+    assert(rc == 0);
+    munmap(map, sizeof(src));
+    close(fd);
+
+    /* Check that PATCH is modified with the new data */
+    fd = open(patch.c_str(), O_RDONLY);
+    map = mmap(NULL, sizeof(src), PROT_READ, MAP_SHARED, fd, 0);
+    assert(map != MAP_FAILED);
+    rc = memcmp(src, map, sizeof(src));
+    assert(rc == 0);
+    munmap(map, sizeof(src));
+    close(fd);
+
+    destroy_vpnor(ctx);
+    free(ctx->flash_bmap);
+
+    return rc;
+}