drivers: watchdog: add watchdog driver for sf32lb platform

Add initial watchdog driver for SF32LB platform

Signed-off-by: Qingsong Gou <gouqs@hotmail.com>

drivers/watchdog/CMakeLists.txt

@@ -65,7 +65,7 @@ zephyr_library_sources_ifdef(CONFIG_WDT_SHELL wdt_shell.c)
 zephyr_library_sources_ifdef(CONFIG_WDT_RENESAS_RA wdt_renesas_ra.c)
 zephyr_library_sources_ifdef(CONFIG_WDT_RENESAS_RX_IWDT wdt_renesas_rx_iwdt.c)
 zephyr_library_sources_ifdef(CONFIG_WDT_NXP_EWM wdt_nxp_ewm.c)
-
+zephyr_library_sources_ifdef(CONFIG_WDT_SF32LB wdt_sf32lb.c)
 zephyr_library_sources_ifdef(CONFIG_WDT_TI_RTI wdt_ti_rti.c)
 
 zephyr_library_sources_ifdef(CONFIG_USERSPACE wdt_handlers.c)

drivers/watchdog/Kconfig

@@ -159,6 +159,8 @@ source "drivers/watchdog/Kconfig.wch"
 
 source "drivers/watchdog/Kconfig.nxp_ewm"
 
+source "drivers/watchdog/Kconfig.sf32lb"
+
 source "drivers/watchdog/Kconfig.xilinx_wwdt"
 
 source "drivers/watchdog/Kconfig.ti_rti"

drivers/watchdog/Kconfig.sf32lb

@@ -0,0 +1,11 @@
+# Copyright (c) 2025 Qingsong Gou <gouqs@hotmail.com>
+# SPDX-License-Identifier: Apache-2.0
+
+config WDT_SF32LB
+	bool "SF32LB Watchdog (WDT) Driver"
+	default y
+	depends on DT_HAS_SIFLI_SF32LB_WDT_ENABLED
+	select HAS_WDT_DISABLE_AT_BOOT
+	select HAS_WDT_NO_CALLBACKS
+	help
+	  Enable WDT driver for SF32LB series MCUs.

drivers/watchdog/wdt_sf32lb.c

@@ -0,0 +1,124 @@
+/*
+ * Copyright (c) 2025, Qingsong Gou <gouqs@hotmail.com>
+ * SPDX-License-Identifier: Apache-2.0
+ */
+#define DT_DRV_COMPAT sifli_sf32lb_wdt
+
+#include <zephyr/arch/cpu.h>
+#include <zephyr/drivers/watchdog.h>
+#include <zephyr/logging/log.h>
+
+#include <register.h>
+
+LOG_MODULE_REGISTER(wdt_sf32lb, CONFIG_WDT_LOG_LEVEL);
+
+#define WDT_CVR0        offsetof(WDT_TypeDef, WDT_CVR0)
+#define WDT_CR          offsetof(WDT_TypeDef, WDT_CR)
+#define WDT_CCR         offsetof(WDT_TypeDef, WDT_CCR)
+
+#define WDT_CMD_START 0x00000076U
+#define WDT_CMD_STOP  0x00000034U
+
+#define WDT_CVR0_MAX 0xFFFFFF
+
+#define WDT_WDT_CR_RESPONSE_MODE1 0U
+
+/* Assume LRC10 clocks WDT (LRC32 support to be added in the future) */
+#define WDT_CLK_KHZ 10
+
+#define WDT_WINDOW_MS_MAX (WDT_CVR0_MAX / WDT_CLK_KHZ)
+
+struct wdt_sf32lb_config {
+	uintptr_t base;
+};
+
+static int wdt_sf32lb_setup(const struct device *dev, uint8_t options)
+{
+	const struct wdt_sf32lb_config *config = dev->config;
+
+	if (options != 0U) {
+		LOG_ERR("Options not supported");
+		return -ENOTSUP;
+	}
+
+	sys_write32(WDT_CMD_START, config->base + WDT_CCR);
+
+	return 0;
+}
+
+static int wdt_sf32lb_disable(const struct device *dev)
+{
+	const struct wdt_sf32lb_config *config = dev->config;
+
+	sys_write32(WDT_CMD_STOP, config->base + WDT_CCR);
+
+	return 0;
+}
+
+static int wdt_sf32lb_install_timeout(const struct device *dev,
+				      const struct wdt_timeout_cfg *wdt_cfg)
+{
+	const struct wdt_sf32lb_config *config = dev->config;
+
+	if (wdt_cfg->flags != WDT_FLAG_RESET_SOC) {
+		LOG_ERR("Only SoC reset supported");
+		return -ENOTSUP;
+	}
+
+	if (wdt_cfg->callback != NULL) {
+		LOG_ERR("Callback not supported");
+		return -ENOTSUP;
+	}
+
+	if (wdt_cfg->window.min != 0U) {
+		LOG_ERR("Window mode not supported!");
+		return -ENOTSUP;
+	};
+
+	if (wdt_cfg->window.max > WDT_WINDOW_MS_MAX) {
+		return -EINVAL;
+	}
+
+	sys_write32(wdt_cfg->window.max * WDT_CLK_KHZ, config->base + WDT_CVR0);
+
+	return 0;
+}
+
+static int wdt_sf32lb_feed(const struct device *dev, int channel_id)
+{
+	const struct wdt_sf32lb_config *config = dev->config;
+
+	sys_write32(WDT_CMD_START, config->base + WDT_CCR);
+
+	return 0;
+}
+
+static DEVICE_API(wdt, wdt_sf32lb_api) = {
+	.setup = wdt_sf32lb_setup,
+	.disable = wdt_sf32lb_disable,
+	.install_timeout = wdt_sf32lb_install_timeout,
+	.feed = wdt_sf32lb_feed,
+};
+
+static int wdt_sf32lb_init(const struct device *dev)
+{
+	const struct wdt_sf32lb_config *config = dev->config;
+	uint32_t cr;
+
+	cr = sys_read32(config->base + WDT_CR);
+	cr &= ~WDT_WDT_CR_RESPONSE_MODE_Msk;
+	cr |= WDT_WDT_CR_RESPONSE_MODE1;
+	sys_write32(cr, config->base + WDT_CR);
+
+	return 0;
+}
+
+#define WDT_SF32LB_INIT(index)                                                                     \
+	static const struct wdt_sf32lb_config wdt_sf32lb_config_##index = {                        \
+		.base = DT_INST_REG_ADDR(index),                                                   \
+	};                                                                                         \
+	DEVICE_DT_INST_DEFINE(index, wdt_sf32lb_init, NULL, NULL,                                  \
+			      &wdt_sf32lb_config_##index, POST_KERNEL,                             \
+			      CONFIG_KERNEL_INIT_PRIORITY_DEVICE, &wdt_sf32lb_api);
+
+DT_INST_FOREACH_STATUS_OKAY(WDT_SF32LB_INIT)