tests: benchmark: multicore: Test PWM with low power modes

Add test that confirms correct operation of PWM
when target enters and leaves low power mode.

Signed-off-by: Sebastian Głąb <sebastian.glab@nordicsemi.no>

CODEOWNERS

@@ -342,6 +342,7 @@
 /tests/benchmarks/multicore/              @carlescufi
 /tests/benchmarks/multicore/idle/         @adamkondraciuk @nrfconnect/ncs-low-level-test
 /tests/benchmarks/multicore/idle_gpio/    @adamkondraciuk @nrfconnect/ncs-low-level-test
+/tests/benchmarks/multicore/idle_with_pwm/  @nrfconnect/ncs-low-level-test
 /tests/benchmarks/i2c_endless/            @nrfconnect/ncs-low-level-test
 /tests/benchmarks/spi_endless/            @nrfconnect/ncs-low-level-test
 /tests/benchmarks/peripheral_load/        @nrfconnect/ncs-low-level-test

tests/benchmarks/multicore/idle_with_pwm/CMakeLists.txt

@@ -0,0 +1,19 @@
+#
+# Copyright (c) 2024 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})
+
+if (NOT SYSBUILD)
+	message(WARNING
+		" This is a multi-image application that should be built using sysbuild.\n"
+		" Add --sysbuild argument to west build command to prepare all the images.")
+endif()
+
+project(idle_with_pwm)
+
+target_sources(app PRIVATE src/main.c)

tests/benchmarks/multicore/idle_with_pwm/Kconfig

@@ -0,0 +1,15 @@
+#
+# Copyright (c) 2024 Nordic Semiconductor ASA
+#
+# SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
+#
+
+config TEST_SLEEP_DURATION_MS
+	int "Amount of time (in miliseconds) the core is sleeping"
+	default 1000
+	help
+		Set sleep duration  to TEST_SLEEP_DURATION_MS miliseconds.
+		Based on value of 'min-residency-us' specified for each power state defined in the DTS,
+		core will enter lowest possible power state.
+
+source "Kconfig.zephyr"

tests/benchmarks/multicore/idle_with_pwm/Kconfig.sysbuild

@@ -0,0 +1,10 @@
+#
+# Copyright (c) 2024 Nordic Semiconductor ASA
+#
+# SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
+#
+
+source "${ZEPHYR_BASE}/share/sysbuild/Kconfig"
+
+config REMOTE_BOARD
+	string "The board used for remote target"

tests/benchmarks/multicore/idle_with_pwm/README.rst

@@ -0,0 +1,72 @@
+.. _multicore_idle_with_pwm_test:
+
+PWM in low power states test
+############################
+
+.. contents::
+   :local:
+   :depth: 2
+
+The test benchmarks the idle behavior of an application that runs on multiple cores and uses PWM driver to light up LED.
+
+Test scenario
+Repeat forever:
+- gradually light up LED (this lasts for ~1 second),
+- disable PWM (set period to 0); This will turn off LED,
+- sleep for 1 second.
+
+Requirements
+************
+
+The test supports the following development kits:
+
+.. table-from-rows:: /includes/sample_board_rows.txt
+   :header: heading
+   :rows: nrf54h20dk_nrf54h20_cpuapp
+
+Overview
+********
+
+The test demonstrates use of PWM with low power modes.
+
+Code stored in :file:`main.c` is compiled for Application and Radio cores.
+Application core uses pwm130 to generate PWM signal on LED2.
+Radio core uses pwm131 to generate PWM signal on GPIO Port 0 pin 7.
+
+There are three test configurations in :file:`testcase.yaml`.
+
+#. 'benchmarks.multicore.idle_with_pwm.nrf54h20dk_cpuapp_cpurad.s2ram'
+   This configuration uses KConfigs that enable entering low power modes. However, logging is disabled here.
+   Core sleeps for time sufficient to enter "suspend-to-ram" power state.
+#. 'benchmarks.multicore.idle_with_pwm.nrf54h20dk_cpuapp_cpurad.sleep'
+   This configuration uses KConfigs that enable entering low power modes. However, logging is disabled here.
+   Core sleeps for time sufficient to enter "suspend-to-idle" power state.
+#. 'benchmarks.multicore.idle_with_pwm.nrf54h20dk_cpuapp_cpurad.no_sleep'
+   This configuration can be used for debug purposes. It has enabled logging while Power Moding is disabled.
+
+Building and running
+********************
+
+.. |test path| replace:: :file:`tests/benchmarks/multicore/idle_with_pwm`
+
+.. include:: /includes/build_and_run_test.txt
+
+To build the test, use configuration setups from :file:`testcase.yaml` using the ``-T`` option.
+See the following examples:
+
+nRF54H20 DK
+  You can build the test for application and radio cores as follows:
+
+  .. code-block:: console
+
+     west build -p -b nrf54h20dk/nrf54h20/cpuapp -T benchmarks.multicore.idle_with_pwm.nrf54h20dk_cpuapp_cpurad.s2ram .
+
+Testing
+=======
+
+After programming the test to your development kit, complete the following steps to test it:
+
+#. Connect the PPK2 Power Profiler Kit or other current measurement device.
+#. Reset the kit.
+#. Observe the LED2 brightness (or use oscilloscope to collect PWM signal on Port 0 pin 7).
+#. When LED2 is OFF power profiler shall indicate low current consumption resulting from both cores being in low power mode.

tests/benchmarks/multicore/idle_with_pwm/boards/nrf54h20dk_nrf54h20_cpuapp.overlay

@@ -0,0 +1,25 @@
+/*
+ * Copyright (c) 2024 Nordic Semiconductor ASA
+ *
+ * SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
+ */
+
+/ {
+	power-states {
+		idle: idle {
+			compatible = "zephyr,power-state";
+			power-state-name = "suspend-to-idle";
+			min-residency-us = <100000>;
+		};
+
+		s2ram: s2ram {
+			compatible = "zephyr,power-state";
+			power-state-name = "suspend-to-ram";
+			min-residency-us = <800000>;
+		};
+	};
+};
+
+&cpu {
+	cpu-power-states = <&idle &s2ram>;
+};

tests/benchmarks/multicore/idle_with_pwm/prj.conf

@@ -0,0 +1,3 @@
+CONFIG_PRINTK=y
+CONFIG_LOG=y
+CONFIG_PWM=y

tests/benchmarks/multicore/idle_with_pwm/prj_s2ram.conf

@@ -0,0 +1,15 @@
+CONFIG_PM=y
+CONFIG_PM_S2RAM=y
+CONFIG_POWEROFF=y
+CONFIG_PM_S2RAM_CUSTOM_MARKING=y
+
+CONFIG_PM_DEVICE=y
+CONFIG_PM_DEVICE_RUNTIME=y
+
+CONFIG_CONSOLE=n
+CONFIG_UART_CONSOLE=n
+CONFIG_SERIAL=n
+CONFIG_BOOT_BANNER=n
+CONFIG_NRFS_MRAM_SERVICE_ENABLED=n
+
+CONFIG_PWM=y

tests/benchmarks/multicore/idle_with_pwm/remote/CMakeLists.txt

@@ -0,0 +1,12 @@
+#
+# Copyright (c) 2024 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(remote)
+
+target_sources(app PRIVATE ../src/main.c)

tests/benchmarks/multicore/idle_with_pwm/remote/Kconfig

@@ -0,0 +1,15 @@
+#
+# Copyright (c) 2024 Nordic Semiconductor ASA
+#
+# SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
+#
+
+config TEST_SLEEP_DURATION_MS
+	int "Amount of time (in miliseconds) the core is sleeping"
+	default 1000
+	help
+		Set sleep duration  to TEST_SLEEP_DURATION_MS miliseconds.
+		Based on value of 'min-residency-us' specified for each power state defined in the DTS,
+		core will enter lowest possible power state.
+
+source "Kconfig.zephyr"

tests/benchmarks/multicore/idle_with_pwm/remote/boards/nrf54h20dk_nrf54h20_cpurad.overlay

@@ -0,0 +1,41 @@
+/*
+ * Copyright (c) 2024 Nordic Semiconductor ASA
+ *
+ * SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
+ */
+
+/ {
+	aliases {
+		pwm-led0 = &pwm_gpio;
+	};
+
+	pwmleds {
+		compatible = "pwm-leds";
+		pwm_gpio: pwm_gpio {
+			pwms = <&pwm131 0 PWM_MSEC(20) PWM_POLARITY_NORMAL>;
+		};
+	};
+};
+
+&pinctrl {
+	/omit-if-no-ref/ pwm131_default: pwm131_default {
+		group1 {
+			psels = <NRF_PSEL(PWM_OUT0, 0, 7)>;
+		};
+	};
+
+	/omit-if-no-ref/ pwm131_sleep: pwm131_sleep {
+		group1 {
+			psels = <NRF_PSEL(PWM_OUT0, 0, 7)>;
+			low-power-enable;
+		};
+	};
+};
+
+&pwm131 {
+	status = "okay";
+	pinctrl-0 = <&pwm131_default>;
+	pinctrl-1 = <&pwm131_sleep>;
+	pinctrl-names = "default", "sleep";
+	memory-regions = <&cpurad_dma_region>;
+};

tests/benchmarks/multicore/idle_with_pwm/remote/prj.conf

@@ -0,0 +1,3 @@
+CONFIG_PRINTK=y
+CONFIG_LOG=y
+CONFIG_PWM=y

tests/benchmarks/multicore/idle_with_pwm/remote/prj_s2ram.conf

@@ -0,0 +1,10 @@
+CONFIG_PM=y
+CONFIG_POWEROFF=y
+
+CONFIG_CONSOLE=n
+CONFIG_UART_CONSOLE=n
+CONFIG_SERIAL=n
+CONFIG_BOOT_BANNER=n
+CONFIG_NRFS_MRAM_SERVICE_ENABLED=n
+
+CONFIG_PWM=y

tests/benchmarks/multicore/idle_with_pwm/src/main.c

@@ -0,0 +1,97 @@
+/*
+ * Copyright (c) 2024 Nordic Semiconductor ASA
+ *
+ * SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
+ */
+
+#include <zephyr/logging/log.h>
+LOG_MODULE_REGISTER(idle_with_pwm, LOG_LEVEL_INF);
+
+#include <zephyr/kernel.h>
+#include <zephyr/pm/pm.h>
+#include <zephyr/drivers/pwm.h>
+
+#if IS_ENABLED(CONFIG_SOC_NRF54H20_CPUAPP)
+/* Alias pwm-led0 = &pwm_led2 */
+static const struct pwm_dt_spec pwm_led = PWM_DT_SPEC_GET(DT_ALIAS(pwm_led0));
+#elif IS_ENABLED(CONFIG_SOC_NRF54H20_CPURAD)
+/* Alias pwm-led0 = &pwm_led3 */
+static const struct pwm_dt_spec pwm_led = PWM_DT_SPEC_GET(DT_ALIAS(pwm_led0));
+#else
+#error "Invalid core selected. "
+#endif
+
+#define PWM_STEPS_PER_SEC	(50)
+
+int main(void)
+{
+	int ret;
+	unsigned int cnt = 0;
+	uint32_t pwm_period;
+	uint32_t pulse_min;
+	uint32_t pulse_max;
+	int32_t pulse_step;
+	uint32_t current_pulse_width;
+
+	if (!pwm_is_ready_dt(&pwm_led)) {
+		LOG_ERR("Device %s is not ready.", pwm_led.dev->name);
+		return -ENODEV;
+	}
+
+	/*
+	 * In case the default pwm_period value cannot be set for
+	 * some PWM hardware, decrease its value until it can.
+	 */
+	pwm_period = PWM_USEC(200U);
+	LOG_INF("Testing PWM period of %d us for channel %d",
+		pwm_period, pwm_led.channel);
+	while (pwm_set_dt(&pwm_led, pwm_period, pwm_period) != 0) {
+		pwm_period /= 2U;
+		LOG_INF("Decreasing period to %u", pwm_period);
+	}
+
+	/*
+	 * There is no distinct change in LED brightness for high PWM duty cycles.
+	 * Thus limit duty cycle to [0; max/2].
+	 */
+	pulse_min = 0;
+	pulse_max = pwm_period / 2;
+	pulse_step = (pulse_max - pulse_min) / PWM_STEPS_PER_SEC;
+	LOG_DBG("Period is %u nsec", pwm_period);
+	LOG_DBG("PWM pulse width varies from %u to %u with %u step",
+		pulse_min, pulse_max, pulse_step);
+
+	LOG_INF("Multicore idle_with_pwm test on %s", CONFIG_BOARD_TARGET);
+	LOG_INF("Core will sleep for %d ms", CONFIG_TEST_SLEEP_DURATION_MS);
+
+	while (1) {
+		LOG_INF("Multicore idle_with_pwm test iteration %u", cnt++);
+
+		/* Light up LED */
+		current_pulse_width = pulse_min;
+		for (int i = 0; i < PWM_STEPS_PER_SEC; i++) {
+			/* set pulse width */
+			ret = pwm_set_dt(&pwm_led, pwm_period, current_pulse_width);
+			if (ret) {
+				LOG_ERR("pwm_set_dt(%u, %u) returned %d",
+					pwm_period, current_pulse_width, ret);
+				return ret;
+			}
+			current_pulse_width += pulse_step;
+			k_msleep(1000 / PWM_STEPS_PER_SEC);
+		}
+
+		/* Disable PWM / LED OFF */
+		ret = pwm_set_dt(&pwm_led, 0, 0);
+		if (ret) {
+			LOG_ERR("pwm_set_dt(%u, %u) returned %d",
+				0, 0, ret);
+			return ret;
+		}
+
+		/* Sleep 1 second */
+		k_msleep(CONFIG_TEST_SLEEP_DURATION_MS);
+	}
+
+	return 0;
+}

tests/benchmarks/multicore/idle_with_pwm/sysbuild.cmake

@@ -0,0 +1,22 @@
+#
+# Copyright (c) 2024 Nordic Semiconductor ASA
+#
+# SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
+#
+
+if("${SB_CONFIG_REMOTE_BOARD}" STREQUAL "")
+  message(FATAL_ERROR "REMOTE_BOARD must be set to a valid board name")
+endif()
+
+# Add remote project
+ExternalZephyrProject_Add(
+    APPLICATION remote
+    SOURCE_DIR ${APP_DIR}/remote
+    BOARD ${SB_CONFIG_REMOTE_BOARD}
+    BOARD_REVISION ${BOARD_REVISION}
+  )
+
+# Add a dependency so that the remote image will be built and flashed first
+add_dependencies(idle_with_pwm remote)
+# Add dependency so that the remote image is flashed first.
+sysbuild_add_dependencies(FLASH idle_with_pwm remote)

tests/benchmarks/multicore/idle_with_pwm/sysbuild/nrf54h20dk_nrf54h20_cpurad.conf

@@ -0,0 +1 @@
+SB_CONFIG_REMOTE_BOARD="nrf54h20dk/nrf54h20/cpurad"