diff --git a/tests/kernel/threads/no-multithreading/prj.conf b/tests/kernel/threads/no-multithreading/prj.conf
index e3a1acdcaaa..51fe9a484fe 100644
--- a/tests/kernel/threads/no-multithreading/prj.conf
+++ b/tests/kernel/threads/no-multithreading/prj.conf
@@ -3,3 +3,5 @@ CONFIG_MULTITHREADING=n
 CONFIG_BT=n
 CONFIG_USB=n
 CONFIG_NETWORKING=n
+CONFIG_ASSERT=n
+CONFIG_SPIN_VALIDATE=n
diff --git a/tests/kernel/threads/no-multithreading/src/main.c b/tests/kernel/threads/no-multithreading/src/main.c
index dc9245805f3..a724cf1d404 100644
--- a/tests/kernel/threads/no-multithreading/src/main.c
+++ b/tests/kernel/threads/no-multithreading/src/main.c
@@ -1,24 +1,111 @@
 /*
  * Copyright (c) 2018 Intel Corporation
+ * Copyright (c) 2021 Nordic Semiconductor ASA
  *
  * SPDX-License-Identifier: Apache-2.0
  */
 #include <zephyr.h>
-#include <tc_util.h>
+#include <device.h>
+#include <ztest.h>
+
+void test_k_busy_wait(void)
+{
+	int64_t now = k_uptime_get();
+	uint32_t watchdog = CONFIG_SYS_CLOCK_HW_CYCLES_PER_SEC;
+
+	while (k_uptime_get() != now) {
+		/* Wait until uptime progresses */
+		watchdog--;
+		if (watchdog == 0) {
+			zassert_false(true, "No progress in uptime");
+		}
+	}
+
+	now = k_uptime_get();
+	/* Check that k_busy_wait is working as expected. */
+	k_busy_wait(10000);
+
+	int64_t diff = k_uptime_get() - now;
+
+	zassert_within(diff, 10, 2, NULL);
+}
+
+static void timeout_handler(struct k_timer *timer)
+{
+	bool *flag = k_timer_user_data_get(timer);
+
+	*flag = true;
+}
+
+K_TIMER_DEFINE(timer, timeout_handler, NULL);
+
+void test_irq_locking(void)
+{
+	volatile bool timeout_run = false;
+
+	k_timer_user_data_set(&timer, (void *)&timeout_run);
+	k_timer_start(&timer, K_MSEC(10), K_NO_WAIT);
+
+	unsigned int key = irq_lock();
+
+	k_busy_wait(15000);
+	zassert_false(timeout_run, "Timeout should not expire because irq is locked");
+
+	irq_unlock(key);
+
+	zassert_true(timeout_run, "Timeout should expire because irq got unlocked");
+}
+
+void test_cpu_idle(void)
+{
+	volatile bool timeout_run = false;
+	int64_t now, diff;
+
+	k_timer_user_data_set(&timer, (void *)&timeout_run);
+	now = k_uptime_get();
+	/* Start timer and go to idle, cpu should sleep until it is waken up
+	 * by sys clock interrupt.
+	 */
+	k_timer_start(&timer, K_MSEC(10), K_NO_WAIT);
+
+	k_cpu_idle();
+
+	diff = k_uptime_get() - now;
+	zassert_true(timeout_run, "Timeout should expire");
+	zassert_within(diff, 10, 2, "Unexpected time passed: %d ms", (int)diff);
+}
+
+#define SYS_INIT_CREATE(level) \
+	static int pre_kernel_##level##_init_func(const struct device *dev) \
+	{ \
+		ARG_UNUSED(dev); \
+		if (init_order != _SYS_INIT_LEVEL_##level && sys_init_result == 0) { \
+			sys_init_result = -1; \
+			return -EIO; \
+		} \
+		init_order++; \
+		return 0;\
+	} \
+	SYS_INIT(pre_kernel_##level##_init_func, level, 0)
+
+static int init_order;
+static int sys_init_result;
+
+FOR_EACH(SYS_INIT_CREATE, (;), PRE_KERNEL_1, PRE_KERNEL_2, POST_KERNEL);
+
+void test_sys_init(void)
+{
+	zassert_equal(init_order, 3, "SYS_INIT failed");
+}
 
-/* The only point to CONFIG_MULTITHREADING=n is to use Zephyr's
- * multiplatform toolchain, linkage and boostrap integration to arrive
- * here so the user can run C code unimpeded.  In general, we don't
- * promise that *any* Zephyr APIs are going to work properly, so don't
- * try to test any.  That means we can't even use the ztest suite
- * framework (which spawns threads internally). Instead, just use
- * tc_util.h helpers.
- */
 void test_main(void)
 {
-	TC_SUITE_START("test_kernel_no_multithread");
-	TC_START(__func__);
-	printk("It works\n");
-	TC_END_RESULT(TC_PASS);
-	TC_SUITE_END("test_kernel_no_multithread", TC_PASS);
+	ztest_test_suite(no_multithreading,
+			 ztest_unit_test(test_k_busy_wait),
+			 ztest_unit_test(test_irq_locking),
+			 ztest_unit_test(test_cpu_idle),
+			 ztest_unit_test(test_sys_init)
+			 );
+
+	ztest_run_test_suite(no_multithreading);
 }
diff --git a/tests/kernel/threads/no-multithreading/testcase.yaml b/tests/kernel/threads/no-multithreading/testcase.yaml
index e8c9af7f418..9d6ddddbcee 100644
--- a/tests/kernel/threads/no-multithreading/testcase.yaml
+++ b/tests/kernel/threads/no-multithreading/testcase.yaml
@@ -2,3 +2,4 @@ tests:
   kernel.threads.no-multithreading:
     tags: kernel
     filter: not CONFIG_SMP
+    platform_allow: qemu_cortex_m3