[stm32] Watchdog IWDG driver

README.md

@@ -396,6 +396,30 @@ Please [discover modm's peripheral drivers for your specific device][discover].
 <td align="center">✕</td>
 <td align="center">✕</td>
 </tr><tr>
+<td align="left">IWDG</td>
+<td align="center">✅</td>
+<td align="center">✅</td>
+<td align="center">✅</td>
+<td align="center">✅</td>
+<td align="center">✅</td>
+<td align="center">✅</td>
+<td align="center">✅</td>
+<td align="center">✅</td>
+<td align="center">○</td>
+<td align="center">✅</td>
+<td align="center">✅</td>
+<td align="center">✅</td>
+<td align="center">✅</td>
+<td align="center">✅</td>
+<td align="center">✕</td>
+<td align="center">✕</td>
+<td align="center">✕</td>
+<td align="center">✕</td>
+<td align="center">✕</td>
+<td align="center">✕</td>
+<td align="center">✕</td>
+<td align="center">✕</td>
+</tr><tr>
 <td align="left">Random Generator</td>
 <td align="center">✕</td>
 <td align="center">✕</td>

examples/nucleo_f072rb/independend_watchdog/main.cpp

@@ -0,0 +1,57 @@
+/*
+ * Copyright (c) 2023, Zühlke Engineering (Austria) GmbH
+ *
+ * This file is part of the modm project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+// ----------------------------------------------------------------------------
+
+#include <modm/board.hpp>
+#include <modm/platform.hpp>
+
+using namespace Board;
+
+/**
+ * If the button is pressed for more than 4 seconds, the MCU will be reset by the Watchdog.
+ * This can be observed by the faster blinking LED after startup.
+ */
+
+int
+main()
+{
+	Board::initialize();
+	LedD13::setOutput();
+	// set the watchdog timeout to 4 seconds
+	Iwdg::initialize(Iwdg::Prescaler::Div32, 0x0FFFu);
+
+	// Use the logging streams to print some messages.
+	// Change MODM_LOG_LEVEL above to enable or disable these messages
+	MODM_LOG_DEBUG << "debug" << modm::endl;
+	MODM_LOG_INFO << "info" << modm::endl;
+	MODM_LOG_WARNING << "warning" << modm::endl;
+	MODM_LOG_ERROR << "error" << modm::endl;
+
+	uint32_t counter(0);
+
+	while (counter < 10)
+	{
+		LedD13::toggle();
+		modm::delay(100ms);
+		MODM_LOG_INFO << "loop: " << counter++ << modm::endl;
+	}
+
+	Iwdg::enable();
+
+	while (1)
+	{
+		LedD13::toggle();
+		modm::delay(500ms);
+		if (!Button::read()) { Iwdg::trigger(); }
+		MODM_LOG_INFO << "loop: " << counter++ << modm::endl;
+	}
+
+	return 0;
+}

examples/nucleo_f072rb/independend_watchdog/project.xml

@@ -0,0 +1,10 @@
+<library>
+  <extends>modm:nucleo-f072rb</extends>
+  <options>
+    <option name="modm:build:build.path">../../../build/nucleo_f072rb/independend_watchdog</option>
+  </options>
+  <modules>
+    <module>modm:build:scons</module>
+    <module>modm:platform:iwdg</module>
+  </modules>
+</library>

src/modm/platform/iwdg/stm32/iwdg.cpp

@@ -0,0 +1,47 @@
+/*
+ * Copyright (c) 2023, Zühlke Engineering (Austria) GmbH
+ *
+ * This file is part of the modm project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+// ----------------------------------------------------------------------------
+
+#include "iwdg.hpp"
+
+void
+Iwdg::initialize(Iwdg::Prescaler prescaler, uint32_t reload)
+{
+	writeKey(writeCommand);
+	IWDG->PR = (IWDG->PR & ~static_cast<uint32_t>(Iwdg::Prescaler::All)) |
+			   static_cast<uint32_t>(prescaler);
+	IWDG->RLR = (IWDG->RLR & ~IWDG_RLR_RL) | (reload << IWDG_RLR_RL_Pos);
+	writeKey(0); // disable access to PR and RLR registers
+}
+
+void
+Iwdg::enable()
+{
+	writeKey(enableCommand);
+}
+
+void
+Iwdg::trigger()
+{
+	writeKey(reloadCommand);
+}
+
+void
+Iwdg::writeKey(uint32_t key)
+{
+	IWDG->KR = (IWDG->KR & ~IWDG_KR_KEY_Msk) | ((key & IWDG_KR_KEY_Msk) << IWDG_KR_KEY_Pos);
+}
+
+Iwdg::Status
+Iwdg::getStatus()
+{
+	const auto status = IWDG->SR & (IWDG_SR_PVU | IWDG_SR_RVU);
+	return static_cast<Status>(status);
+};

src/modm/platform/iwdg/stm32/iwdg.hpp

@@ -0,0 +1,56 @@
+/*
+ * Copyright (c) 2023, Zühlke Engineering (Austria) GmbH
+ *
+ * This file is part of the modm project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+// ----------------------------------------------------------------------------
+
+#pragma once
+#include "../device.hpp"
+
+class Iwdg
+{
+public:
+	enum class
+	Prescaler : uint32_t
+	{
+		Div4 = 0,
+		Div8 = IWDG_PR_PR_0,
+		Div16 = IWDG_PR_PR_1,
+		Div32 = IWDG_PR_PR_1 | IWDG_PR_PR_0,
+		Div64 = IWDG_PR_PR_2,
+		Div128 = IWDG_PR_PR_2 | IWDG_PR_PR_0,
+		Div256 = IWDG_PR_PR_2 | IWDG_PR_PR_1,
+		All = IWDG_PR_PR_2 | IWDG_PR_PR_1 | IWDG_PR_PR_0,
+	};
+
+	enum class
+	Status : uint32_t
+	{
+		None = 0,
+		Prescaler = IWDG_SR_PVU,
+		Reload = IWDG_SR_RVU,
+		All = IWDG_SR_PVU | IWDG_SR_RVU,
+	};
+
+	static void
+	initialize(Prescaler prescaler, uint32_t reload);
+	static void
+	enable();
+	static void
+	trigger();
+	static Status
+	getStatus();
+
+private:
+	static constexpr uint32_t reloadCommand = 0xAAAA;
+	static constexpr uint32_t writeCommand = 0x5555;
+	static constexpr uint32_t enableCommand = 0xCCCC;
+
+	static void
+	writeKey(uint32_t key);
+};

src/modm/platform/iwdg/stm32/module.lb

@@ -0,0 +1,28 @@
+#!/usr/bin/env python3
+# -*- coding: utf-8 -*-
+#
+# Copyright (c) 2023, Zühlke Engineering (Austria) GmbH
+#
+# This file is part of the modm project.
+#
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+# -----------------------------------------------------------------------------
+
+def init(module):
+    module.name = ":platform:iwdg"
+    module.description = "Independent watchdog"
+
+def prepare(module, options):
+    device = options[":target"]
+    target = device.identifier
+    if target["family"] in ["h7"]:
+        # STM32H7 is not yet supported with any IWDG implementation im modm
+        return False
+    return device.has_driver("iwdg:stm32")
+
+def build(env):
+    env.outbasepath = "modm/src/modm/platform/iwdg"
+    env.copy("iwdg.hpp")
+    env.copy("iwdg.cpp")