From 6afed2f3493a00c3dcd0cb64e66969596a0356c1 Mon Sep 17 00:00:00 2001
From: zhji <jzhgonha@163.com>
Date: Sun, 1 Jun 2025 16:18:31 +0800
Subject: [PATCH] [feat] add watchdog

---
 driver/CMakeLists.txt         |  1 +
 driver/inc/reg/watchdog_reg.h | 29 +++++++++++++++++++++++++++++
 driver/inc/watchdog.h         | 19 +++++++++++++++++++
 driver/src/watchdog.c         |  6 ++++++
 example/boot2/main.c          |  3 ++-
 5 files changed, 57 insertions(+), 1 deletion(-)
 create mode 100644 driver/inc/reg/watchdog_reg.h
 create mode 100644 driver/inc/watchdog.h
 create mode 100644 driver/src/watchdog.c

diff --git a/driver/CMakeLists.txt b/driver/CMakeLists.txt
index 5abaed0..6716f89 100644
--- a/driver/CMakeLists.txt
+++ b/driver/CMakeLists.txt
@@ -12,6 +12,7 @@ src/timer.c
 src/dma.c
 src/uart.c
 src/usb.c
+src/watchdog.c
 )
 
 set(TARGET driver)
diff --git a/driver/inc/reg/watchdog_reg.h b/driver/inc/reg/watchdog_reg.h
new file mode 100644
index 0000000..a54e97c
--- /dev/null
+++ b/driver/inc/reg/watchdog_reg.h
@@ -0,0 +1,29 @@
+#ifndef __HARDWARE_WATCHDOG_REG_H__
+#define __HARDWARE_WATCHDOG_REG_H__
+
+#define WATCHDOG_TICK_CYCLES_POS  (0U)
+#define WATCHDOG_TICK_CYCLES_MASK (0x1FF << WATCHDOG_TICK_CYCLES_POS)
+#define WATCHDOG_TICK_ENABLE      (1 << 9U)
+#define WATCHDOG_TICK_RUNNING     (1 << 10U)
+#define WATCHDOG_TICK_COUNT_POS   (11U)
+#define WATCHDOG_TICK_COUNT_MASK  (0x1FF << WATCHDOG_TICK_COUNT_POS)
+
+typedef struct {
+    io_rw_32 ctrl;
+    io_wo_32 load;
+    io_ro_32 reason;
+    io_rw_32 scratch[8];
+    io_rw_32 tick;
+} watchdog_hw_t;
+
+#define watchdog_hw ((watchdog_hw_t *const)WATCHDOG_BASE)
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __HARDWARE_WATCHDOG_REG_H__ */
diff --git a/driver/inc/watchdog.h b/driver/inc/watchdog.h
new file mode 100644
index 0000000..da7b2b9
--- /dev/null
+++ b/driver/inc/watchdog.h
@@ -0,0 +1,19 @@
+#ifndef __HARDWARE_WATCHDOG_H__
+#define __HARDWARE_WATCHDOG_H__
+
+#include "reg.h"
+#include "watchdog_reg.h"
+
+
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+void watchdog_start_tick(uint16_t cycles);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __HARDWARE_WATCHDOG_H__ */
diff --git a/driver/src/watchdog.c b/driver/src/watchdog.c
new file mode 100644
index 0000000..930b6f6
--- /dev/null
+++ b/driver/src/watchdog.c
@@ -0,0 +1,6 @@
+#include "watchdog.h"
+
+void watchdog_start_tick(uint16_t cycles)
+{
+    watchdog_hw->tick = (cycles << WATCHDOG_TICK_CYCLES_POS) | WATCHDOG_TICK_ENABLE;
+}
diff --git a/example/boot2/main.c b/example/boot2/main.c
index f7603b7..343bdf5 100644
--- a/example/boot2/main.c
+++ b/example/boot2/main.c
@@ -56,6 +56,7 @@ void __attribute__((section(".text.boot2_pre"))) boot2_copy_self(void)
 #include "clock.h"
 #include "uart.h"
 #include "flash.h"
+#include "watchdog.h"
 #include "timer.h"
 #include "stdio.h"
 
@@ -224,7 +225,7 @@ int main(void)
     gpio_init(0, GPIO_FUNC_UART | GPIO_PULL_UP | GPIO_DRIVE_4MA); /* UART_TX pin */
     gpio_init(1, GPIO_FUNC_UART | GPIO_PULL_UP | GPIO_SCHMITT | GPIO_PAD_IE | GPIO_PAD_OD); /* UART_RX pin */
     uart_init(UART_ID_0, &uart_cfg);
-    *(volatile uint32_t *)(WATCHDOG_BASE + 0x2C) = ((1 << 9) | (12 << 0));
+    watchdog_start_tick(12); /* 12MHz / 12 = 1MHz, as 1us */
     timer_start();
 
     gpio_init(2, GPIO_FUNC_NULL | GPIO_PULL_DOWN | GPIO_SCHMITT | GPIO_PAD_IE | GPIO_PAD_OD); /* boot pin */