diff --git a/tests/lib/Makefile.inc b/tests/lib/Makefile.inc
index 2c80b93..23d8d34 100644
--- a/tests/lib/Makefile.inc
+++ b/tests/lib/Makefile.inc
@@ -14,6 +14,7 @@
 tests-y += imd_cbmem-ramstage-test
 tests-y += region_file-test
 tests-y += stack-test
+tests-y += memset-test
 
 string-test-srcs += tests/lib/string-test.c
 string-test-srcs += src/lib/string.c
@@ -76,3 +77,6 @@
 stack-test-srcs += tests/lib/stack-test.c
 stack-test-srcs += src/lib/stack.c
 stack-test-srcs += tests/stubs/console.c
+
+memset-test-srcs += tests/lib/memset-test.c
+memset-test-srcs += src/lib/memset.c
diff --git a/tests/lib/memset-test.c b/tests/lib/memset-test.c
new file mode 100644
index 0000000..1247577
--- /dev/null
+++ b/tests/lib/memset-test.c
@@ -0,0 +1,120 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#include <stdlib.h>
+#include <tests/test.h>
+#include <commonlib/helpers.h>
+#include <types.h>
+#include <string.h>
+
+#define MEMSET_BUFFER_SZ (4 * KiB)
+
+struct memset_test_state {
+	u8 *base_buffer;
+	u8 *helper_buffer;
+};
+
+static int setup_test(void **state)
+{
+	struct memset_test_state *s = malloc(sizeof(struct memset_test_state));
+
+	u8 *buf = malloc(MEMSET_BUFFER_SZ);
+	u8 *helper_buf = malloc(MEMSET_BUFFER_SZ);
+	if (!buf || !helper_buf)
+		goto error;
+
+	s->base_buffer = buf;
+	s->helper_buffer = helper_buf;
+	*state = s;
+
+	return 0;
+
+error:
+	free(buf);
+	free(helper_buf);
+	return -1;
+}
+
+static int teardown_test(void **state)
+{
+	struct memset_test_state *s = *state;
+
+	if (s) {
+		free(s->base_buffer);
+		free(s->helper_buffer);
+	}
+
+	free(s);
+
+	return 0;
+}
+
+static void test_memset_full_range(void **state)
+{
+	struct memset_test_state *s = *state;
+
+	for (int i = 0; i < MEMSET_BUFFER_SZ; ++i)
+		s->helper_buffer[i] = 0x42;
+
+	memset(s->base_buffer, 0x42, MEMSET_BUFFER_SZ);
+	assert_memory_equal(s->base_buffer, s->helper_buffer, MEMSET_BUFFER_SZ);
+}
+
+static void test_memset_subrange(void **state)
+{
+	struct memset_test_state *s = *state;
+	int i = 0;
+
+	for (; i < MEMSET_BUFFER_SZ / 2; ++i)
+		s->helper_buffer[i] = 0xEF;
+	for (; i < MEMSET_BUFFER_SZ; ++i)
+		s->helper_buffer[i] = 0xCD;
+
+	/* Expect correct buffer subranges to be filled */
+	memset(s->base_buffer, 0xEF, MEMSET_BUFFER_SZ / 2);
+	memset(s->base_buffer + MEMSET_BUFFER_SZ / 2, 0xCD, MEMSET_BUFFER_SZ / 2);
+	assert_memory_equal(s->base_buffer, s->helper_buffer, MEMSET_BUFFER_SZ);
+}
+
+static void test_memset_zero_size(void **state)
+{
+	struct memset_test_state *s = *state;
+
+	for (int i = 0; i < MEMSET_BUFFER_SZ; ++i) {
+		s->base_buffer[i] = 0xFF;
+		s->helper_buffer[i] = 0xFF;
+	}
+
+	/* Expect no change in buffer after calling memset with zero size */
+	memset(s->base_buffer, 0xAA, 0);
+	assert_memory_equal(s->base_buffer, s->helper_buffer, MEMSET_BUFFER_SZ);
+}
+
+static void test_memset_one_byte(void **state)
+{
+	struct memset_test_state *s = *state;
+
+	for (int i = 0; i < MEMSET_BUFFER_SZ; ++i) {
+		s->base_buffer[i] = 0x66;
+		s->helper_buffer[i] = 0x66;
+	}
+
+	s->helper_buffer[MEMSET_BUFFER_SZ / 4] = 0xCC;
+	memset(&s->base_buffer[MEMSET_BUFFER_SZ / 4], 0xCC, 1);
+	assert_memory_equal(s->base_buffer, s->helper_buffer, MEMSET_BUFFER_SZ);
+}
+
+int main(void)
+{
+	const struct CMUnitTest tests[] = {
+		cmocka_unit_test_setup_teardown(test_memset_full_range,
+				setup_test, teardown_test),
+		cmocka_unit_test_setup_teardown(test_memset_subrange,
+				setup_test, teardown_test),
+		cmocka_unit_test_setup_teardown(test_memset_zero_size,
+				setup_test, teardown_test),
+		cmocka_unit_test_setup_teardown(test_memset_one_byte,
+				setup_test, teardown_test),
+	};
+
+	return cmocka_run_group_tests(tests, NULL, NULL);
+}