Added iwdg support + early wakeup

include/libopencm3/stm32/common/iwdg_common_all.h

@@ -48,6 +48,9 @@ specific memorymap.h header before including this header file.*/
 /** Status register (IWDG_SR) */
 #define IWDG_SR				MMIO32(IWDG_BASE + 0x0c)
 
+/** Early wake-up interrupt register (IWDG_EWCR) */
+#define IWDG_EWCR           MMIO32(IWDG_BASE + 0x14)
+
 /* --- IWDG_KR values ------------------------------------------------------ */
 
 /* Bits [31:16]: Reserved. */
@@ -83,6 +86,14 @@ specific memorymap.h header before including this header file.*/
 /* Double definition: 0x06 and 0x07 both mean DIV256 as per datasheet. */
 /* #define IWDG_PR_DIV256			0x7 */
 
+/* --- IWDG_EWCR values ----------------------------------------------------- */
+
+#define IWDG_EWCR_EWIT_SHIFT    0x0
+#define IWDG_EWCR_EWIT_MASK     (0xFFF << IWDG_EWCR_EWIT_SHIFT)
+#define IWDG_EWCR_EWIC          (1 << 14)
+#define IWDG_EWCR_EWIE          (1 << 15)
+
+
 /* --- IWDG_RLR values ----------------------------------------------------- */
 
 /* Bits [31:12]: Reserved. */
@@ -108,6 +119,9 @@ void iwdg_set_period_ms(uint32_t period);
 bool iwdg_reload_busy(void);
 bool iwdg_prescaler_busy(void);
 void iwdg_reset(void);
+void iwdg_enable_early_wakeup(uint16_t wakeup_ms);
+void iwdg_disable_early_wakeup(void);
+void iwdg_ack_early_wakeup(void);
 
 END_DECLS
 

include/libopencm3/stm32/common/iwdg_common_v2.h

@@ -47,6 +47,10 @@ specific memorymap.h header before including this header file.*/
 /** Window Register (IWDG_WINR) */
 #define IWDG_WINR				MMIO32(IWDG_BASE + 0x10)
 
+
+/** Early wake-up register (IWDG_EWCR) */
+#define IWDG_EWCR				MMIO32(IWDG_BASE + 0x14)
+
 /*****************************************************************************/
 /* Register values                                                           */
 /*****************************************************************************/

include/libopencm3/stm32/iwdg.h

@@ -38,6 +38,8 @@
 #       include <libopencm3/stm32/l1/iwdg.h>
 #elif defined(STM32L4)
 #       include <libopencm3/stm32/l4/iwdg.h>
+#elif defined(STM32U5)
+#       include <libopencm3/stm32/u5/iwdg.h>
 #elif defined(STM32G0)
 #       include <libopencm3/stm32/g0/iwdg.h>
 #elif defined(STM32G4)

include/libopencm3/stm32/u5/iwdg.h

@@ -0,0 +1,38 @@
+/** @defgroup iwdg_defines IWDG Defines
+ *
+ * @brief <b>Defined Constants and Types for the STM32U5xx Independent Watchdog
+ * Timer</b>
+ *
+ * @ingroup STM32U5xx_defines
+ *
+ * @version 1.0.0
+ *
+ * @date 16 October 2024
+ *
+ * LGPL License Terms @ref lgpl_license
+ */
+/*
+ * This file is part of the libopencm3 project.
+ *
+ * Copyright (C) 2010 Thomas Otto <tommi@viadmin.org>
+ *
+ * This library is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this library.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef LIBOPENCM3_IWDG_H
+#define LIBOPENCM3_IWDG_H
+
+#include <libopencm3/stm32/common/iwdg_common_v2.h>
+
+#endif

lib/stm32/common/iwdg_common_all.c

@@ -150,3 +150,42 @@ void iwdg_reset(void)
 }
 /**@}*/
 
+
+/*---------------------------------------------------------------------------*/
+/** @brief IWDG enable early wake-up
+
+The watchdog timer will generate IRQ when reaches Early wakeup window value.
+The early interrupt is generated when the IWDCNT is lower or equal to EWIT
+register.
+ */
+void iwdg_enable_early_wakeup(uint16_t wakeup_ms) {
+	IWDG_KR = IWDG_KR_UNLOCK;
+    // IWDG_EWCR |= IWDG_EWCR_EWIE;
+	wakeup_ms &= IWDG_EWCR_EWIT_MASK;
+	wakeup_ms <<= IWDG_EWCR_EWIT_SHIFT;
+	IWDG_EWCR = IWDG_EWCR_EWIE | wakeup_ms;
+}
+/**@}*/
+
+/*---------------------------------------------------------------------------*/
+/** @brief Disables the watchdog early wake-up
+
+Disable watchdog early wake-up IRQ
+ */
+void iwdg_disable_early_wakeup(void) {
+	IWDG_KR = IWDG_KR_UNLOCK;
+    IWDG_EWCR &= ~IWDG_EWCR_EWIE;
+}
+/**@}*/
+
+/*---------------------------------------------------------------------------*/
+/** @brief Acknowledge early wake-up
+
+The software must write a 1 into this bit in order to acknowledge the early
+wake-up interrupt and to clear the EWIF flag.
+ */
+void iwdg_ack_early_wakeup(void) {
+	IWDG_KR = IWDG_KR_UNLOCK;
+    IWDG_EWCR |= IWDG_EWCR_EWIC;
+}
+/**@}*/

lib/stm32/u5/Makefile

@@ -35,6 +35,7 @@ TGT_CFLAGS	+= $(STANDARD_FLAGS)
 
 ARFLAGS		= rcs
 
+OBJS += iwdg_common_all.o
 OBJS += i2c_common_v2.o
 OBJS += usart_common_all.o usart_common_v2.o
 OBJS += gpio_common_all.o gpio_common_f0234.o