tests: drivers: timer: Test k_msleep() and k_busy_wait() accuracy

nordic-segl · nordic-piks · commit 4154581978aa · 2026-05-18T12:56:01.000+02:00
Add test that compares k_msleep() and k_busy_wait() delay
with ticks counted by a hardware timer.
Check that software delay has decent tolerance.

Signed-off-by: Sebastian Głąb &lt;sebastian.glab@nordicsemi.no&gt;
diff --git a/tests/drivers/timer/delay_accuracy/CMakeLists.txt b/tests/drivers/timer/delay_accuracy/CMakeLists.txt
@@ -0,0 +1,12 @@
+#
+# Copyright (c) 2026 Nordic Semiconductor ASA
+#
+# SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
+#
+
+cmake_minimum_required(VERSION 3.20.0)
+
+find_package(Zephyr REQUIRED HINTS $ENV{ZEPHYR_BASE})
+project(delay_accuracy)
+
+target_sources(app PRIVATE src/main.c)
diff --git a/tests/drivers/timer/delay_accuracy/Kconfig b/tests/drivers/timer/delay_accuracy/Kconfig
@@ -0,0 +1,23 @@
+#
+# Copyright (c) 2026 Nordic Semiconductor ASA
+#
+# SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
+#
+
+config TEST_TOLERANCE_PERCENT
+	int "Accepted tolerance in percent"
+	default 1
+	help
+	  When set to the value of 1 then test will pass if difference
+	  between actual timer count and expected timer count is less
+	  than one percent.
+
+config TEST_TIMER_FREQUENCY_MHZ
+	int "Timer frequency in MHz"
+	default 4
+	help
+	  This value must take into account hardware limitations.
+	  Calculations are int32_t based and may overflow on devices
+	  with low accuracy or high frequency of the timer.
+
+source "Kconfig.zephyr"
diff --git a/tests/drivers/timer/delay_accuracy/Kconfig.sysbuild b/tests/drivers/timer/delay_accuracy/Kconfig.sysbuild
@@ -0,0 +1,10 @@
+#
+# Copyright (c) 2026 Nordic Semiconductor ASA
+#
+# SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
+#
+
+config PARTITION_MANAGER
+	default n
+
+source "share/sysbuild/Kconfig"
diff --git a/tests/drivers/timer/delay_accuracy/boards/nrf54h20dk_nrf54h20_cpuapp.overlay b/tests/drivers/timer/delay_accuracy/boards/nrf54h20dk_nrf54h20_cpuapp.overlay
@@ -0,0 +1,9 @@
+/*
+ * Copyright (c) 2026 Nordic Semiconductor ASA
+ *
+ * SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
+ */
+
+tst_timer: &timer130 {
+	status = "okay";
+};
diff --git a/tests/drivers/timer/delay_accuracy/boards/nrf54h20dk_nrf54h20_cpuflpr.conf b/tests/drivers/timer/delay_accuracy/boards/nrf54h20dk_nrf54h20_cpuflpr.conf
@@ -0,0 +1 @@
+CONFIG_TEST_TIMER_FREQUENCY_MHZ=5
diff --git a/tests/drivers/timer/delay_accuracy/boards/nrf54h20dk_nrf54h20_cpuflpr.overlay b/tests/drivers/timer/delay_accuracy/boards/nrf54h20dk_nrf54h20_cpuflpr.overlay
@@ -0,0 +1,9 @@
+/*
+ * Copyright (c) 2026 Nordic Semiconductor ASA
+ *
+ * SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
+ */
+
+tst_timer: &timer120 {
+	status = "okay";
+};
diff --git a/tests/drivers/timer/delay_accuracy/boards/nrf54h20dk_nrf54h20_cpuppr.overlay b/tests/drivers/timer/delay_accuracy/boards/nrf54h20dk_nrf54h20_cpuppr.overlay
@@ -0,0 +1 @@
+#include "nrf54h20dk_nrf54h20_cpuapp.overlay"
diff --git a/tests/drivers/timer/delay_accuracy/boards/nrf54h20dk_nrf54h20_cpurad.overlay b/tests/drivers/timer/delay_accuracy/boards/nrf54h20dk_nrf54h20_cpurad.overlay
@@ -0,0 +1 @@
+#include "nrf54h20dk_nrf54h20_cpuapp.overlay"
diff --git a/tests/drivers/timer/delay_accuracy/boards/nrf54l15dk_nrf54l05_cpuapp.overlay b/tests/drivers/timer/delay_accuracy/boards/nrf54l15dk_nrf54l05_cpuapp.overlay
@@ -0,0 +1 @@
+#include "nrf54l15dk_nrf54l15_cpuapp.overlay"
diff --git a/tests/drivers/timer/delay_accuracy/boards/nrf54l15dk_nrf54l10_cpuapp.overlay b/tests/drivers/timer/delay_accuracy/boards/nrf54l15dk_nrf54l10_cpuapp.overlay
@@ -0,0 +1 @@
+#include "nrf54l15dk_nrf54l15_cpuapp.overlay"
diff --git a/tests/drivers/timer/delay_accuracy/boards/nrf54l15dk_nrf54l15_cpuapp.overlay b/tests/drivers/timer/delay_accuracy/boards/nrf54l15dk_nrf54l15_cpuapp.overlay
@@ -0,0 +1,9 @@
+/*
+ * Copyright (c) 2026 Nordic Semiconductor ASA
+ *
+ * SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
+ */
+
+tst_timer: &timer20 {
+	status = "okay";
+};
diff --git a/tests/drivers/timer/delay_accuracy/boards/nrf54l15dk_nrf54l15_cpuflpr.overlay b/tests/drivers/timer/delay_accuracy/boards/nrf54l15dk_nrf54l15_cpuflpr.overlay
@@ -0,0 +1 @@
+#include "nrf54l15dk_nrf54l15_cpuapp.overlay"
diff --git a/tests/drivers/timer/delay_accuracy/boards/nrf54lm20dk_nrf54lm20a_cpuapp.overlay b/tests/drivers/timer/delay_accuracy/boards/nrf54lm20dk_nrf54lm20a_cpuapp.overlay
@@ -0,0 +1 @@
+#include "nrf54l15dk_nrf54l15_cpuapp.overlay"
diff --git a/tests/drivers/timer/delay_accuracy/boards/nrf54lm20dk_nrf54lm20a_cpuflpr.overlay b/tests/drivers/timer/delay_accuracy/boards/nrf54lm20dk_nrf54lm20a_cpuflpr.overlay
@@ -0,0 +1 @@
+#include "nrf54l15dk_nrf54l15_cpuapp.overlay"
diff --git a/tests/drivers/timer/delay_accuracy/boards/nrf54lm20dk_nrf54lm20b_cpuapp.overlay b/tests/drivers/timer/delay_accuracy/boards/nrf54lm20dk_nrf54lm20b_cpuapp.overlay
@@ -0,0 +1 @@
+#include "nrf54l15dk_nrf54l15_cpuapp.overlay"
diff --git a/tests/drivers/timer/delay_accuracy/boards/nrf54ls05dk_nrf54ls05a_cpuapp.overlay b/tests/drivers/timer/delay_accuracy/boards/nrf54ls05dk_nrf54ls05a_cpuapp.overlay
@@ -0,0 +1 @@
+#include "nrf54l15dk_nrf54l15_cpuapp.overlay"
diff --git a/tests/drivers/timer/delay_accuracy/boards/nrf54ls05dk_nrf54ls05b_cpuapp.overlay b/tests/drivers/timer/delay_accuracy/boards/nrf54ls05dk_nrf54ls05b_cpuapp.overlay
@@ -0,0 +1 @@
+#include "nrf54l15dk_nrf54l15_cpuapp.overlay"
diff --git a/tests/drivers/timer/delay_accuracy/boards/nrf54lv10dk_nrf54lv10a_cpuapp.overlay b/tests/drivers/timer/delay_accuracy/boards/nrf54lv10dk_nrf54lv10a_cpuapp.overlay
@@ -0,0 +1 @@
+#include "nrf54l15dk_nrf54l15_cpuapp.overlay"
diff --git a/tests/drivers/timer/delay_accuracy/boards/nrf54lv10dk_nrf54lv10a_cpuflpr.overlay b/tests/drivers/timer/delay_accuracy/boards/nrf54lv10dk_nrf54lv10a_cpuflpr.overlay
@@ -0,0 +1 @@
+#include "nrf54l15dk_nrf54l15_cpuapp.overlay"
diff --git a/tests/drivers/timer/delay_accuracy/boards/nrf9251dk_nrf9251_cpuapp.overlay b/tests/drivers/timer/delay_accuracy/boards/nrf9251dk_nrf9251_cpuapp.overlay
@@ -0,0 +1 @@
+#include "nrf54h20dk_nrf54h20_cpuapp.overlay"
diff --git a/tests/drivers/timer/delay_accuracy/boards/nrf9251dk_nrf9251_cpuflpr.conf b/tests/drivers/timer/delay_accuracy/boards/nrf9251dk_nrf9251_cpuflpr.conf
@@ -0,0 +1 @@
+CONFIG_TEST_TIMER_FREQUENCY_MHZ=5
diff --git a/tests/drivers/timer/delay_accuracy/boards/nrf9251dk_nrf9251_cpuflpr.overlay b/tests/drivers/timer/delay_accuracy/boards/nrf9251dk_nrf9251_cpuflpr.overlay
@@ -0,0 +1 @@
+#include "nrf54h20dk_nrf54h20_cpuflpr.overlay"
diff --git a/tests/drivers/timer/delay_accuracy/boards/nrf9251dk_nrf9251_cpuppr.overlay b/tests/drivers/timer/delay_accuracy/boards/nrf9251dk_nrf9251_cpuppr.overlay
@@ -0,0 +1 @@
+#include "nrf54h20dk_nrf54h20_cpuapp.overlay"
diff --git a/tests/drivers/timer/delay_accuracy/prj.conf b/tests/drivers/timer/delay_accuracy/prj.conf
@@ -0,0 +1,4 @@
+CONFIG_ZTEST=y
+
+CONFIG_NRFX_TIMER=y
+CONFIG_LOG=y
diff --git a/tests/drivers/timer/delay_accuracy/src/main.c b/tests/drivers/timer/delay_accuracy/src/main.c
@@ -0,0 +1,97 @@
+/*
+ * Copyright (c) 2026, Nordic Semiconductor ASA
+ *
+ * SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
+ */
+
+#include <zephyr/kernel.h>
+#include <zephyr/ztest.h>
+#include <nrfx_timer.h>
+#include <stdlib.h>
+
+#include <zephyr/logging/log.h>
+LOG_MODULE_REGISTER(delay_accuracy, LOG_LEVEL_INF);
+
+nrfx_timer_t test_timer = NRFX_TIMER_INSTANCE(DT_REG_ADDR(DT_NODELABEL(tst_timer)));
+
+static void *suite_setup(void)
+{
+	int ret;
+
+	/* Configure Timer. */
+	uint32_t base_frequency = NRFX_TIMER_BASE_FREQUENCY_GET(&test_timer);
+	nrfx_timer_config_t timer_config =
+		NRFX_TIMER_DEFAULT_CONFIG(MHZ(CONFIG_TEST_TIMER_FREQUENCY_MHZ));
+	timer_config.bit_width = NRF_TIMER_BIT_WIDTH_32;
+	timer_config.mode = NRF_TIMER_MODE_TIMER;
+
+	TC_PRINT("Delay accuracy test on %s\n", CONFIG_BOARD_TARGET);
+	TC_PRINT("Timer base frequency: %d Hz\n", base_frequency);
+	TC_PRINT("Timer configured frequency: %d Hz\n", timer_config.frequency);
+	TC_PRINT("===================================================================\n");
+
+	ret = nrfx_timer_init(&test_timer, &timer_config, NULL);
+	zassert_true(ret == 0, "nrfx_timer_init() failed, ret = 0x%08X", ret);
+
+	nrfx_timer_enable(&test_timer);
+
+	return NULL;
+}
+
+
+static void test_k_msleep(int32_t ms)
+{
+	nrfx_timer_clear(&test_timer);
+	k_msleep(ms);
+	nrfx_timer_capture(&test_timer, NRF_TIMER_CC_CHANNEL0);
+	uint32_t pulses = nrfx_timer_capture_get(&test_timer, NRF_TIMER_CC_CHANNEL0);
+	uint32_t expected_pulses = nrfx_timer_ms_to_ticks(&test_timer, ms);
+	/* Instead of using floating numbers, scale up by 100.
+	 * Then, use integer division and modulo to get value
+	 * with two digits after decimal point.
+	 */
+	uint32_t diff_percent_x100 = abs(expected_pulses - pulses) * 100 * 100 / expected_pulses;
+
+	TC_PRINT("timer actual pulses = %u\n", pulses);
+	TC_PRINT("expected pulses = %u\n", expected_pulses);
+	TC_PRINT("diff = %u.%u [%%]\n", diff_percent_x100 / 100, diff_percent_x100 % 100);
+	zassert_true(diff_percent_x100 < CONFIG_TEST_TOLERANCE_PERCENT * 100);
+}
+
+static void test_k_busy_wait(int32_t ms)
+{
+	nrfx_timer_clear(&test_timer);
+	k_busy_wait(ms * 1000);
+	nrfx_timer_capture(&test_timer, NRF_TIMER_CC_CHANNEL0);
+	uint32_t pulses = nrfx_timer_capture_get(&test_timer, NRF_TIMER_CC_CHANNEL0);
+	uint32_t expected_pulses = nrfx_timer_ms_to_ticks(&test_timer, ms);
+	uint32_t diff_percent_x100 = abs(expected_pulses - pulses) * 100 * 100 / expected_pulses;
+
+	TC_PRINT("timer actual pulses = %u\n", pulses);
+	TC_PRINT("expected pulses = %u\n", expected_pulses);
+	TC_PRINT("diff = %u.%u [%%]\n", diff_percent_x100 / 100, diff_percent_x100 % 100);
+	zassert_true(diff_percent_x100 < CONFIG_TEST_TOLERANCE_PERCENT * 100);
+}
+
+ZTEST(delay_accuracy, test_k_busy_wait_01_sec)
+{
+	test_k_busy_wait(1000);
+}
+
+ZTEST(delay_accuracy, test_k_busy_wait_05_sec)
+{
+	test_k_busy_wait(5000);
+}
+
+ZTEST(delay_accuracy, test_k_msleep_01_sec)
+{
+	test_k_msleep(1000);
+}
+
+ZTEST(delay_accuracy, test_k_msleep_05_sec)
+{
+	test_k_msleep(5000);
+}
+
+
+ZTEST_SUITE(delay_accuracy, NULL, suite_setup, NULL, NULL, NULL);
diff --git a/tests/drivers/timer/delay_accuracy/sysbuild/vpr_launcher/boards/nrf54h20dk_nrf54h20_cpuapp.overlay b/tests/drivers/timer/delay_accuracy/sysbuild/vpr_launcher/boards/nrf54h20dk_nrf54h20_cpuapp.overlay
@@ -0,0 +1,9 @@
+&timer120 {
+	status = "reserved";
+	interrupt-parent = <&cpuflpr_clic>;
+};
+
+&timer130 {
+	status = "reserved";
+	interrupt-parent = <&cpuppr_clic>;
+};
diff --git a/tests/drivers/timer/delay_accuracy/sysbuild/vpr_launcher/boards/nrf9251dk_nrf9251_cpuapp.overlay b/tests/drivers/timer/delay_accuracy/sysbuild/vpr_launcher/boards/nrf9251dk_nrf9251_cpuapp.overlay
@@ -0,0 +1,9 @@
+&timer120 {
+	status = "reserved";
+	interrupt-parent = <&cpuflpr_clic>;
+};
+
+&timer130 {
+	status = "reserved";
+	interrupt-parent = <&cpuppr_clic>;
+};
diff --git a/tests/drivers/timer/delay_accuracy/sysbuild/vpr_launcher/prj.conf b/tests/drivers/timer/delay_accuracy/sysbuild/vpr_launcher/prj.conf
@@ -0,0 +1 @@
+# nothing here
diff --git a/tests/drivers/timer/delay_accuracy/testcase.yaml b/tests/drivers/timer/delay_accuracy/testcase.yaml
@@ -0,0 +1,30 @@
+common:
+  tags:
+    - drivers
+    - ci_tests_drivers_timer
+  harness: ztest
+  timeout: 20
+
+tests:
+  drivers.timer.delay_accuracy:
+    platform_allow:
+      - nrf54h20dk/nrf54h20/cpuapp
+      - nrf54h20dk/nrf54h20/cpuflpr
+      - nrf54h20dk/nrf54h20/cpuppr
+      - nrf54h20dk/nrf54h20/cpurad
+      - nrf54l15dk/nrf54l05/cpuapp
+      - nrf54l15dk/nrf54l10/cpuapp
+      - nrf54l15dk/nrf54l15/cpuapp
+      - nrf54l15dk/nrf54l15/cpuflpr
+      - nrf54lm20dk/nrf54lm20a/cpuapp
+      - nrf54lm20dk/nrf54lm20a/cpuflpr
+      - nrf54lm20dk/nrf54lm20b/cpuapp
+      - nrf54ls05dk/nrf54ls05a/cpuapp
+      - nrf54ls05dk/nrf54ls05b/cpuapp
+      - nrf54lv10dk/nrf54lv10a/cpuapp
+      - nrf54lv10dk/nrf54lv10a/cpuflpr
+      - nrf9251dk/nrf9251/cpuapp
+      - nrf9251dk/nrf9251/cpuflpr
+      - nrf9251dk/nrf9251/cpuppr
+    integration_platforms:
+      - nrf54l15dk/nrf54l15/cpuapp

Original file line number	Diff line number	Diff line change
`@@ -0,0 +1 @@`
	`1`	`+#include "nrf54h20dk_nrf54h20_cpuapp.overlay"`
Original file line number	Diff line number	Diff line change
`@@ -0,0 +1 @@`
	`1`	`+#include "nrf54l15dk_nrf54l15_cpuapp.overlay"`