samples: watchdog: add the ch32v003evt to the sample

This commit adds a runner wrapper for the 'minichlink' program which
offers a free, open mechanism to use the CH-LinkE programming dongle for
the CH32V003.

https://github.com/cnlohr/ch32v003fun/tree/master/minichlink

Signed-off-by: Michael Hope <michaelh@juju.nz>
Signed-off-by: Dhiru Kholia <dhiru.kholia@gmail.com>

MAINTAINERS.yml

@@ -4871,6 +4871,14 @@ West:
   labels:
     - "platform: TI"
 
+"West project: hal_wch":
+  status: maintained
+  maintainers:
+    - nzmichaelh
+    - kholia
+  files:
+    - modules/hal_wch/
+
 "West project: hal_wurthelektronik":
   status: maintained
   maintainers:

boards/common/minichlink.board.cmake

@@ -0,0 +1,5 @@
+# Copyright (c) 2024 Dhiru Kholia
+# SPDX-License-Identifier: Apache-2.0
+
+board_set_flasher_ifnset(minichlink)
+board_finalize_runner_args(minichlink)

boards/wch/ch32v003evt/Kconfig.ch32v003evt

@@ -0,0 +1,5 @@
+# Copyright (c) 2024 Michael Hope
+# SPDX-License-Identifier: Apache-2.0
+
+config BOARD_CH32V003EVT
+	select SOC_CH32V003

boards/wch/ch32v003evt/board.cmake

@@ -0,0 +1,8 @@
+# Copyright (c) 2024 Michael Hope
+# SPDX-License-Identifier: Apache-2.0
+
+board_runner_args(openocd "--use-elf" "--cmd-reset-halt" "halt")
+include(${ZEPHYR_BASE}/boards/common/openocd.board.cmake)
+
+board_runner_args(minichlink)
+include(${ZEPHYR_BASE}/boards/common/minichlink.board.cmake)

boards/wch/ch32v003evt/board.yml

@@ -0,0 +1,6 @@
+board:
+  name: ch32v003evt
+  full_name: WCH CH32V003EVT
+  vendor: wch
+  socs:
+    - name: ch32v003

boards/wch/ch32v003evt/ch32v003evt-pinctrl.dtsi

@@ -0,0 +1,21 @@
+/*
+ * Copyright (c) 2024 Michael Hope <michaelh@juju.nz>
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <zephyr/dt-bindings/pinctrl/ch32v003-pinctrl.h>
+
+&pinctrl {
+	usart1_default: usart1_default {
+		group1 {
+			pinmux = <USART1_TX_PD5_0>;
+			output-high;
+			drive-push-pull;
+			slew-rate = "max-speed-10mhz";
+		};
+		group2 {
+			pinmux = <USART1_RX_PD6_0>;
+			bias-pull-up;
+		};
+	};
+};

boards/wch/ch32v003evt/ch32v003evt.dts

@@ -0,0 +1,58 @@
+/*
+ * Copyright (c) 2024 Michael Hope <michaelh@juju.nz>
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+/dts-v1/;
+
+#include <wch/ch32v00x.dtsi>
+#include "ch32v003evt-pinctrl.dtsi"
+
+/ {
+	model = "ch32v003evt";
+	compatible = "wch,ch32v003";
+
+	chosen {
+		zephyr,sram = &sram0;
+		zephyr,flash = &flash0;
+		zephyr,console = &usart1;
+		zephyr,shell-uart = &usart1;
+	};
+
+	leds {
+		compatible = "gpio-leds";
+
+		red_led: led0 {
+			gpios = <&gpiod 4 GPIO_ACTIVE_HIGH>;
+		};
+	};
+
+	aliases {
+		led0 = &red_led;
+	};
+};
+
+&clk_hse {
+	clock-frequency = <DT_FREQ_M(24)>;
+	status = "okay";
+};
+
+&pll {
+	clocks = <&clk_hse>;
+	status = "okay";
+};
+
+&rcc {
+	clocks = <&pll>;
+};
+
+&gpiod {
+	status = "okay";
+};
+
+&usart1 {
+	status = "okay";
+	current-speed = <115200>;
+	pinctrl-0 = <&usart1_default>;
+	pinctrl-names = "default";
+};

boards/wch/ch32v003evt/ch32v003evt.yaml

@@ -0,0 +1,11 @@
+identifier: ch32v003evt
+name: WCH CH32V003 Evaluation Board
+type: mcu
+arch: riscv
+toolchain:
+  - cross-compile
+  - zephyr
+ram: 2
+flash: 16
+supported:
+  - gpio

boards/wch/ch32v003evt/ch32v003evt_defconfig

@@ -0,0 +1,8 @@
+# Copyright (c) 2024 Michael Hope
+# SPDX-License-Identifier: Apache-2.0
+
+CONFIG_MAIN_STACK_SIZE=512
+
+CONFIG_IDLE_STACK_SIZE=256
+
+CONFIG_ISR_STACK_SIZE=256

boards/wch/ch32v003evt/doc/index.rst

@@ -0,0 +1,107 @@
+.. zephyr:board:: ch32v003evt
+
+Overview
+********
+
+The `WCH`_ CH32V003EVT hardware provides support for QingKe 32-bit RISC-V2A
+processor and the following devices:
+
+* CLOCK
+* :abbr:`GPIO (General Purpose Input Output)`
+* :abbr:`NVIC (Nested Vectored Interrupt Controller)`
+
+The board is equipped with two LEDs. The `WCH webpage on CH32V003`_ contains
+the processor's information and the datasheet.
+
+Hardware
+********
+
+The QingKe 32-bit RISC-V2A processor of the WCH CH32V003EVT is clocked by an
+external crystal and runs at 48 MHz.
+
+Supported Features
+==================
+
+The ``ch32v003evt`` board target supports the following hardware features:
+
++-----------+------------+----------------------+
+| Interface | Controller | Driver/Component     |
++===========+============+======================+
+| CLOCK     | on-chip    | clock_control        |
++-----------+------------+----------------------+
+| GPIO      | on-chip    | gpio                 |
++-----------+------------+----------------------+
+| PWM       | on-chip    | pwm                  |
++-----------+------------+----------------------+
+| PINCTRL   | on-chip    | pinctrl              |
++-----------+------------+----------------------+
+| TIMER     | on-chip    | timer                |
++-----------+------------+----------------------+
+| UART      | on-chip    | uart                 |
++-----------+------------+----------------------+
+
+Other hardware features have not been enabled yet for this board.
+
+Connections and IOs
+===================
+
+LED
+---
+
+* LED1 = Unconnected. Connect to an I/O pin (PD4).
+
+Programming and Debugging
+*************************
+
+Applications for the ``ch32v003evt`` board target can be built and flashed
+in the usual way (see :ref:`build_an_application` and :ref:`application_run`
+for more details); however, an external programmer is required since the board
+does not have any built-in debug support.
+
+The following pins of the external programmer must be connected to the
+following pins on the PCB (see image):
+
+* VCC = VCC (do not power the board from the USB port at the same time)
+* GND = GND
+* SWIO = PD1
+
+Flashing
+========
+
+You can use ``minichlink`` to flash the board. Once ``minichlink`` has been set
+up, build and flash applications as usual (see :ref:`build_an_application` and
+:ref:`application_run` for more details).
+
+Here is an example for the :zephyr:code-sample:`blinky` application.
+
+.. zephyr-app-commands::
+   :zephyr-app: samples/basic/blinky
+   :board: ch32v003evt
+   :goals: build flash
+
+Debugging
+=========
+
+This board can be debugged via OpenOCD or ``minichlink``.
+
+Testing the LED on the WCH CH32V003EVT
+**************************************
+
+There is 1 sample program that allow you to test that the LED on the board is
+working properly with Zephyr:
+
+.. code-block:: console
+
+   samples/basic/blinky
+
+You can build and flash the examples to make sure Zephyr is running
+correctly on your board. The button and LED definitions can be found
+in :zephyr_file:`boards/wch/ch32v003evt/ch32v003evt.dts`.
+
+References
+**********
+
+.. target-notes::
+
+.. _WCH: http://www.wch-ic.com
+.. _WCH webpage on CH32V003: https://www.wch-ic.com/products/CH32V003.html

boards/wch/ch32v003evt/support/openocd.cfg

@@ -0,0 +1,15 @@
+#interface wlink
+adapter driver wlink
+wlink_set
+set _CHIPNAME riscv
+jtag newtap $_CHIPNAME cpu -irlen 5 -expected-id 0x00001
+
+set _TARGETNAME $_CHIPNAME.cpu
+
+target create $_TARGETNAME.0 riscv -chain-position $_TARGETNAME
+$_TARGETNAME.0 configure  -work-area-phys 0x80000000 -work-area-size 10000 -work-area-backup 1
+set _FLASHNAME $_CHIPNAME.flash
+
+flash bank $_FLASHNAME wch_riscv 0x00000000 0 0 0 $_TARGETNAME.0
+
+echo "Ready for Remote Connections"

boards/wch/index.rst

@@ -0,0 +1,10 @@
+.. _boards-wch:
+
+WCH - Nanjing Qinheng Microelectronics Co.
+##########################################
+
+.. toctree::
+   :maxdepth: 1
+   :glob:
+
+   **/*

drivers/clock_control/CMakeLists.txt

@@ -98,3 +98,4 @@ endif()
 zephyr_library_sources_ifdef(CONFIG_CLOCK_CONTROL_AST10X0 clock_control_ast10x0.c)
 zephyr_library_sources_ifdef(CONFIG_CLOCK_CONTROL_MAX32 clock_control_max32.c)
 zephyr_library_sources_ifdef(CONFIG_CLOCK_CONTROL_NRF_AUXPLL clock_control_nrf_auxpll.c)
+zephyr_library_sources_ifdef(CONFIG_CLOCK_CONTROL_WCH_RCC clock_control_wch_rcc.c)

drivers/clock_control/Kconfig

@@ -100,4 +100,6 @@ source "drivers/clock_control/Kconfig.arm_scmi"
 
 source "drivers/clock_control/Kconfig.silabs"
 
+source "drivers/clock_control/Kconfig.wch_rcc"
+
 endif # CLOCK_CONTROL

drivers/clock_control/Kconfig.wch_rcc

@@ -0,0 +1,7 @@
+# Copyright (c) 2024 Michael Hope
+# SPDX-License-Identifier: Apache-2.0
+
+config CLOCK_CONTROL_WCH_RCC
+	bool "WCH CH32V00x Reset and Clock Control (RCC) driver"
+	default y
+	depends on DT_HAS_WCH_RCC_ENABLED

drivers/clock_control/clock_control_wch_rcc.c

@@ -0,0 +1,154 @@
+/*
+ * Copyright (c) 2024 Michael Hope
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#define DT_DRV_COMPAT wch_rcc
+
+#include <stdint.h>
+
+#include <zephyr/arch/cpu.h>
+#include <zephyr/device.h>
+#include <zephyr/devicetree.h>
+#include <zephyr/drivers/clock_control.h>
+#include <zephyr/sys/util_macro.h>
+
+#include <ch32_rcc.h>
+
+#define WCH_RCC_CLOCK_ID_OFFSET(id) (((id) >> 5) & 0xFF)
+#define WCH_RCC_CLOCK_ID_BIT(id)    ((id) & 0x1F)
+
+#if DT_NODE_HAS_STATUS_OKAY(DT_NODELABEL(pll)) && DT_NODE_HAS_PROP(DT_NODELABEL(pll), clocks)
+#define DT_PLL_CLOCKS_CTRL DT_CLOCKS_CTLR(DT_NODELABEL(pll))
+#if DT_SAME_NODE(DT_PLL_CLOCKS_CTRL, DT_NODELABEL(clk_hsi))
+#define WCH_RCC_PLL_SRC_IS_HSI 1
+#endif
+#if DT_SAME_NODE(DT_PLL_CLOCKS_CTRL, DT_NODELABEL(clk_hse))
+#define WCH_RCC_PLL_SRC_IS_HSE 1
+#endif
+#endif
+
+#define DT_RCC_CLOCKS_CTRL DT_CLOCKS_CTLR(DT_NODELABEL(rcc))
+#if DT_SAME_NODE(DT_RCC_CLOCKS_CTRL, DT_NODELABEL(pll))
+#define WCH_RCC_SRC_IS_PLL 1
+#endif
+#if DT_SAME_NODE(DT_RCC_CLOCKS_CTRL, DT_NODELABEL(clk_hsi))
+#define WCH_RCC_SRC_IS_HSI 1
+#endif
+#if DT_SAME_NODE(DT_RCC_CLOCKS_CTRL, DT_NODELABEL(clk_hse))
+#define WCH_RCC_SRC_IS_HSE 1
+#endif
+
+struct clock_control_wch_rcc_config {
+	RCC_TypeDef *regs;
+};
+
+static int clock_control_wch_rcc_on(const struct device *dev, clock_control_subsys_t sys)
+{
+	const struct clock_control_wch_rcc_config *config = dev->config;
+	RCC_TypeDef *regs = config->regs;
+	uint8_t id = (uintptr_t)sys;
+	uint32_t reg = (uint32_t)(&regs->AHBPCENR + WCH_RCC_CLOCK_ID_OFFSET(id));
+	uint32_t val = sys_read32(reg);
+
+	reg |= BIT(WCH_RCC_CLOCK_ID_BIT(id));
+	sys_write32(val, reg);
+
+	return 0;
+}
+
+static int clock_control_wch_rcc_get_rate(const struct device *dev, clock_control_subsys_t sys,
+					  uint32_t *rate)
+{
+	const struct clock_control_wch_rcc_config *config = dev->config;
+	RCC_TypeDef *regs = config->regs;
+	uint32_t cfgr0 = regs->CFGR0;
+	uint32_t sysclk = CONFIG_SYS_CLOCK_HW_CYCLES_PER_SEC;
+	uint32_t ahbclk = sysclk;
+
+	if ((cfgr0 & RCC_HPRE_3) != 0) {
+		/* The range 0b1000 divides by a power of 2, where 0b1000 is /2, 0b1001 is /4, etc.
+		 */
+		ahbclk /= 2 << ((cfgr0 >> 4) & 0x07);
+	} else {
+		/* The range 0b0nnn divides by n + 1, where 0b0000 is /1, 0b001 is /2, etc. */
+		ahbclk /= ((cfgr0 >> 4) & 0x07) + 1;
+	}
+
+	/* The datasheet says that AHB == APB1 == APB2, but the registers imply that APB1 and APB2
+	 * can be divided from the AHB clock. Assume that the clock tree diagram is correct and
+	 * always return AHB.
+	 */
+	*rate = ahbclk;
+	return 0;
+}
+
+static struct clock_control_driver_api clock_control_wch_rcc_api = {
+	.on = clock_control_wch_rcc_on,
+	.get_rate = clock_control_wch_rcc_get_rate,
+};
+
+static int clock_control_wch_rcc_init(const struct device *dev)
+{
+	if (IS_ENABLED(CONFIG_DT_HAS_WCH_CH32V00X_PLL_CLOCK_ENABLED)) {
+		/* Disable the PLL before potentially changing the input clocks. */
+		RCC->CTLR &= ~RCC_PLLON;
+	}
+
+	/* Always enable the LSI. */
+	RCC->RSTSCKR |= RCC_LSION;
+	while ((RCC->RSTSCKR & RCC_LSIRDY) == 0) {
+	}
+
+	if (IS_ENABLED(CONFIG_DT_HAS_WCH_CH32V00X_HSI_CLOCK_ENABLED)) {
+		RCC->CTLR |= RCC_HSION;
+		while ((RCC->CTLR & RCC_HSIRDY) == 0) {
+		}
+	}
+
+	if (IS_ENABLED(CONFIG_DT_HAS_WCH_CH32V00X_HSE_CLOCK_ENABLED)) {
+		RCC->CTLR |= RCC_HSEON;
+		while ((RCC->CTLR & RCC_HSERDY) == 0) {
+		}
+	}
+
+	if (IS_ENABLED(CONFIG_DT_HAS_WCH_CH32V00X_PLL_CLOCK_ENABLED)) {
+		if (IS_ENABLED(WCH_RCC_PLL_SRC_IS_HSE)) {
+			RCC->CFGR0 |= RCC_PLLSRC;
+		} else if (IS_ENABLED(WCH_RCC_PLL_SRC_IS_HSI)) {
+			RCC->CFGR0 &= ~RCC_PLLSRC;
+		}
+		RCC->CTLR |= RCC_PLLON;
+		while ((RCC->CTLR & RCC_PLLRDY) == 0) {
+		}
+	}
+
+	if (IS_ENABLED(WCH_RCC_SRC_IS_HSI)) {
+		RCC->CFGR0 = (RCC->CFGR0 & ~RCC_SW) | RCC_SW_HSI;
+	} else if (IS_ENABLED(WCH_RCC_SRC_IS_HSE)) {
+		RCC->CFGR0 = (RCC->CFGR0 & ~RCC_SW) | RCC_SW_HSE;
+	} else if (IS_ENABLED(WCH_RCC_SRC_IS_PLL)) {
+		RCC->CFGR0 = (RCC->CFGR0 & ~RCC_SW) | RCC_SW_PLL;
+	}
+	RCC->CTLR |= RCC_CSSON;
+
+	/* Clear the interrupt flags. */
+	RCC->INTR = RCC_CSSC | RCC_PLLRDYC | RCC_HSERDYC | RCC_LSIRDYC;
+	/* HCLK = SYSCLK = APB1 */
+	RCC->CFGR0 = (RCC->CFGR0 & ~RCC_HPRE) | RCC_HPRE_DIV1;
+	/* Set the Flash to 0 wait state */
+	FLASH->ACTLR = (FLASH->ACTLR & ~FLASH_ACTLR_LATENCY) | FLASH_ACTLR_LATENCY_1;
+
+	return 0;
+}
+
+#define CLOCK_CONTROL_WCH_RCC_INIT(idx)                                                            \
+	static const struct clock_control_wch_rcc_config clock_control_wch_rcc_##idx##_config = {  \
+		.regs = (RCC_TypeDef *)DT_INST_REG_ADDR(idx),                                      \
+	};                                                                                         \
+	DEVICE_DT_INST_DEFINE(idx, clock_control_wch_rcc_init, NULL, NULL,                         \
+			      &clock_control_wch_rcc_##idx##_config, PRE_KERNEL_1,                 \
+			      CONFIG_CLOCK_CONTROL_INIT_PRIORITY, &clock_control_wch_rcc_api);
+
+DT_INST_FOREACH_STATUS_OKAY(CLOCK_CONTROL_WCH_RCC_INIT)

drivers/gpio/CMakeLists.txt

@@ -94,6 +94,7 @@ zephyr_library_sources_ifdef(CONFIG_GPIO_TCA6424A   gpio_tca6424a.c)
 zephyr_library_sources_ifdef(CONFIG_GPIO_TELINK_B91 gpio_b91.c)
 zephyr_library_sources_ifdef(CONFIG_GPIO_TEST       gpio_test.c)
 zephyr_library_sources_ifdef(CONFIG_GPIO_TLE9104    gpio_tle9104.c)
+zephyr_library_sources_ifdef(CONFIG_GPIO_WCH_GPIO   wch_gpio_ch32v00x.c)
 zephyr_library_sources_ifdef(CONFIG_GPIO_XEC        gpio_mchp_xec.c)
 zephyr_library_sources_ifdef(CONFIG_GPIO_XEC_V2     gpio_mchp_xec_v2.c)
 zephyr_library_sources_ifdef(CONFIG_GPIO_XLNX_AXI   gpio_xlnx_axi.c)

drivers/gpio/Kconfig

@@ -178,6 +178,7 @@ source "drivers/gpio/Kconfig.sx1509b"
 source "drivers/gpio/Kconfig.tca6424a"
 source "drivers/gpio/Kconfig.test"
 source "drivers/gpio/Kconfig.tle9104"
+source "drivers/gpio/Kconfig.wch_ch32v00x"
 source "drivers/gpio/Kconfig.xec"
 source "drivers/gpio/Kconfig.xlnx"
 source "drivers/gpio/Kconfig.xlnx_ps"

drivers/gpio/Kconfig.wch_ch32v00x

@@ -0,0 +1,7 @@
+# Copyright (c) 2024 Michael Hope
+# SPDX-License-Identifier: Apache-2.0
+
+config GPIO_WCH_GPIO
+	bool "WCH CH32V00x GPIO driver"
+	depends on DT_HAS_WCH_GPIO_ENABLED
+	default y

drivers/gpio/wch_gpio_ch32v00x.c

@@ -0,0 +1,144 @@
+/*
+ * Copyright (c) 2024 Michael Hope
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <zephyr/drivers/clock_control.h>
+#include <zephyr/drivers/gpio.h>
+#include <zephyr/drivers/gpio/gpio_utils.h>
+#include <zephyr/dt-bindings/gpio/gpio.h>
+#include <zephyr/irq.h>
+
+#include <ch32_gpio.h>
+
+#define DT_DRV_COMPAT wch_gpio
+
+struct gpio_ch32v00x_config {
+	struct gpio_driver_config common;
+	GPIO_TypeDef *regs;
+	const struct device *clock_dev;
+	uint8_t clock_id;
+};
+
+struct gpio_ch32v00x_data {
+	struct gpio_driver_data common;
+};
+
+static int gpio_ch32v00x_configure(const struct device *dev, gpio_pin_t pin, gpio_flags_t flags)
+{
+	const struct gpio_ch32v00x_config *config = dev->config;
+	GPIO_TypeDef *regs = config->regs;
+	uint32_t cnf_mode;
+	uint32_t bshr = 0;
+
+	if ((flags & GPIO_OUTPUT) != 0) {
+		cnf_mode = 0x01;
+		if ((flags & GPIO_OUTPUT_INIT_HIGH) != 0) {
+			bshr = 1 << pin;
+		} else if ((flags & GPIO_OUTPUT_INIT_LOW) != 0) {
+			bshr = 1 << (16 + pin);
+		}
+	} else if ((flags & GPIO_INPUT) != 0) {
+		if ((flags & GPIO_PULL_UP) != 0) {
+			cnf_mode = 0x08;
+			bshr = 1 << pin;
+		} else if ((flags & GPIO_PULL_DOWN) != 0) {
+			cnf_mode = 0x08;
+			bshr = 1 << (16 + pin);
+		} else {
+			cnf_mode = 0x04;
+		}
+	} else {
+		cnf_mode = 0x00;
+	}
+
+	regs->CFGLR = (regs->CFGLR & ~(0x0F << (4 * pin))) | (cnf_mode << (4 * pin));
+	regs->BSHR = bshr;
+
+	return 0;
+}
+
+static int gpio_ch32v00x_port_get_raw(const struct device *dev, uint32_t *value)
+{
+	const struct gpio_ch32v00x_config *config = dev->config;
+
+	*value = config->regs->INDR;
+
+	return 0;
+}
+
+static int gpio_ch32v00x_port_set_masked_raw(const struct device *dev, uint32_t mask,
+					     uint32_t value)
+{
+	const struct gpio_ch32v00x_config *config = dev->config;
+
+	config->regs->BSHR = ((~value & mask) << 16) | (value & mask);
+
+	return 0;
+}
+
+static int gpio_ch32v00x_port_set_bits_raw(const struct device *dev, uint32_t pins)
+{
+	const struct gpio_ch32v00x_config *config = dev->config;
+
+	config->regs->BSHR = pins;
+
+	return 0;
+}
+
+static int gpio_ch32v00x_port_clear_bits_raw(const struct device *dev, uint32_t pins)
+{
+	const struct gpio_ch32v00x_config *config = dev->config;
+
+	config->regs->BCR = pins;
+
+	return 0;
+}
+
+static int gpio_ch32v00x_port_toggle_bits(const struct device *dev, uint32_t pins)
+{
+	const struct gpio_ch32v00x_config *config = dev->config;
+	uint32_t changed = (config->regs->OUTDR ^ pins) & pins;
+
+	config->regs->BSHR = (changed & pins) | (~changed & pins) << 16;
+
+	return 0;
+}
+
+static const struct gpio_driver_api gpio_ch32v00x_driver_api = {
+	.pin_configure = gpio_ch32v00x_configure,
+	.port_get_raw = gpio_ch32v00x_port_get_raw,
+	.port_set_masked_raw = gpio_ch32v00x_port_set_masked_raw,
+	.port_set_bits_raw = gpio_ch32v00x_port_set_bits_raw,
+	.port_clear_bits_raw = gpio_ch32v00x_port_clear_bits_raw,
+	.port_toggle_bits = gpio_ch32v00x_port_toggle_bits,
+};
+
+static int gpio_ch32v00x_init(const struct device *dev)
+{
+	const struct gpio_ch32v00x_config *config = dev->config;
+
+	clock_control_on(config->clock_dev, (clock_control_subsys_t *)(uintptr_t)config->clock_id);
+
+	return 0;
+}
+
+#define GPIO_CH32V00X_INIT(idx)                                                                    \
+	static const struct gpio_ch32v00x_config gpio_ch32v00x_##idx##_config = {                  \
+		.common =                                                                          \
+			{                                                                          \
+				.port_pin_mask = GPIO_PORT_PIN_MASK_FROM_DT_INST(idx),             \
+			},                                                                         \
+		.regs = (GPIO_TypeDef *)DT_INST_REG_ADDR(idx),                                     \
+		.clock_dev = DEVICE_DT_GET(DT_INST_CLOCKS_CTLR(idx)),                              \
+		.clock_id = DT_INST_CLOCKS_CELL(idx, id),                                          \
+	};                                                                                         \
+                                                                                                   \
+	static struct gpio_ch32v00x_data gpio_ch32v00x_##idx##_data;                               \
+                                                                                                   \
+	DEVICE_DT_INST_DEFINE(idx, gpio_ch32v00x_init, NULL, &gpio_ch32v00x_##idx##_data,          \
+			      &gpio_ch32v00x_##idx##_config, PRE_KERNEL_1,                         \
+			      CONFIG_GPIO_INIT_PRIORITY, &gpio_ch32v00x_driver_api);
+
+DT_INST_FOREACH_STATUS_OKAY(GPIO_CH32V00X_INIT)

drivers/interrupt_controller/CMakeLists.txt

@@ -43,6 +43,7 @@ zephyr_library_sources_ifdef(CONFIG_NXP_PINT                intc_nxp_pint.c)
 zephyr_library_sources_ifdef(CONFIG_RENESAS_RA_ICU          intc_renesas_ra_icu.c)
 zephyr_library_sources_ifdef(CONFIG_NXP_IRQSTEER            intc_nxp_irqsteer.c)
 zephyr_library_sources_ifdef(CONFIG_INTC_MTK_ADSP           intc_mtk_adsp.c)
+zephyr_library_sources_ifdef(CONFIG_WCH_PFIC                intc_wch_pfic.c)
 
 if(CONFIG_INTEL_VTD_ICTL)
   zephyr_library_include_directories(${ZEPHYR_BASE}/arch/x86/include)

drivers/interrupt_controller/Kconfig

@@ -108,4 +108,6 @@ source "drivers/interrupt_controller/Kconfig.nxp_irqsteer"
 
 source "drivers/interrupt_controller/Kconfig.mtk_adsp"
 
+source "drivers/interrupt_controller/Kconfig.wch_pfic"
+
 endmenu

drivers/interrupt_controller/Kconfig.wch_pfic

@@ -0,0 +1,9 @@
+# Copyright (c) 2024 Michael Hope
+# SPDX-License-Identifier: Apache-2.0
+
+config WCH_PFIC
+	bool "WCH Programmable Fast Interrupt Controller (PFIC)"
+	default y
+	depends on DT_HAS_WCH_PFIC_ENABLED
+	help
+	  Interrupt controller for WCH PFIC.

drivers/interrupt_controller/intc_wch_pfic.c

@@ -0,0 +1,43 @@
+/*
+ * Copyright (c) 2024 Michael Hope
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#define DT_DRV_COMPAT wch_pfic
+
+#include <ch32_pfic.h>
+
+#include <zephyr/arch/cpu.h>
+#include <zephyr/init.h>
+#include <zephyr/irq.h>
+#include <zephyr/kernel.h>
+
+#define SEVONPEND (1 << 4)
+#define WFITOWFE  (1 << 3)
+
+void arch_irq_enable(unsigned int irq)
+{
+	PFIC->IENR[irq / 32] = 1 << (irq % 32);
+}
+
+void arch_irq_disable(unsigned int irq)
+{
+	PFIC->IRER[irq / 32] |= 1 << (irq % 32);
+}
+
+int arch_irq_is_enabled(unsigned int irq)
+{
+	return ((PFIC->ISR[irq >> 5] & (1 << (irq & 0x1F))) != 0);
+}
+
+static int pfic_init(void)
+{
+	/* `wfi` is called with interrupts disabled. Configure the PFIC to wake up on any event,
+	 * including any interrupt.
+	 */
+	PFIC->SCTLR = SEVONPEND | WFITOWFE;
+	return 0;
+}
+
+SYS_INIT(pfic_init, PRE_KERNEL_1, CONFIG_INTC_INIT_PRIORITY);

drivers/pinctrl/CMakeLists.txt

@@ -40,5 +40,6 @@ zephyr_library_sources_ifdef(CONFIG_PINCTRL_IMX_SCU pinctrl_imx_scu.c)
 zephyr_library_sources_ifdef(CONFIG_PINCTRL_MAX32 pinctrl_max32.c)
 zephyr_library_sources_ifdef(CONFIG_PINCTRL_IMX_SCMI pinctrl_imx_scmi.c)
 zephyr_library_sources_ifdef(CONFIG_PINCTRL_MCHP_MEC5 pinctrl_mchp_mec5.c)
+zephyr_library_sources_ifdef(CONFIG_PINCTRL_WCH_AFIO pinctrl_wch_afio.c)
 
 add_subdirectory(renesas)

drivers/pinctrl/Kconfig

@@ -67,6 +67,7 @@ source "drivers/pinctrl/Kconfig.ene"
 source "drivers/pinctrl/Kconfig.zynqmp"
 source "drivers/pinctrl/Kconfig.max32"
 source "drivers/pinctrl/Kconfig.mec5"
+source "drivers/pinctrl/Kconfig.wch_afio"
 
 rsource "renesas/Kconfig"
 

drivers/pinctrl/Kconfig.wch_afio

@@ -0,0 +1,9 @@
+# Copyright (c) 2024 Michael Hope
+# SPDX-License-Identifier: Apache-2.0
+
+config PINCTRL_WCH_AFIO
+	bool "WCH AFIO pin controller driver"
+	default y
+	depends on DT_HAS_WCH_AFIO_ENABLED
+	help
+	  WCH AFIO pin controller driver.

drivers/pinctrl/pinctrl_wch_afio.c

@@ -0,0 +1,75 @@
+/*
+ * Copyright (c) 2024 Michael Hope
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <zephyr/drivers/pinctrl.h>
+#include <zephyr/dt-bindings/pinctrl/ch32v003-pinctrl.h>
+
+#include <ch32_pinctrl.h>
+
+static GPIO_TypeDef *const wch_afio_pinctrl_regs[] = {
+	GPIOA,
+	GPIOC,
+	GPIOD,
+};
+
+int pinctrl_configure_pins(const pinctrl_soc_pin_t *pins, uint8_t pin_cnt, uintptr_t reg)
+{
+	int i;
+
+	for (i = 0; i < pin_cnt; i++, pins++) {
+		uint8_t port = (pins->config >> CH32V003_PINCTRL_PORT_SHIFT) & 0x03;
+		uint8_t pin = (pins->config >> CH32V003_PINCTRL_PIN_SHIFT) & 0x0F;
+		uint8_t bit0 = (pins->config >> CH32V003_PINCTRL_RM_BASE_SHIFT) & 0x1F;
+		uint8_t remap = (pins->config >> CH32V003_PINCTRL_RM_SHIFT) & 0x3;
+		GPIO_TypeDef *regs = wch_afio_pinctrl_regs[port];
+		uint32_t pcfr1 = AFIO->PCFR1;
+		uint8_t cfg = 0;
+
+		if (pins->output_high || pins->output_low) {
+			cfg |= (pins->slew_rate + 1);
+			if (pins->drive_open_drain) {
+				cfg |= BIT(2);
+			}
+			/* Select the alternate function */
+			cfg |= BIT(3);
+		} else {
+			if (pins->bias_pull_up || pins->bias_pull_down) {
+				cfg |= BIT(3);
+			}
+		}
+		regs->CFGLR = (regs->CFGLR & ~(0x0F << (pin * 4))) | (cfg << (pin * 4));
+
+		if (pins->output_high) {
+			regs->OUTDR |= BIT(pin);
+			regs->BSHR |= BIT(pin);
+		} else if (pins->output_low) {
+			regs->OUTDR |= BIT(pin);
+			/* Reset the pin. */
+			regs->BSHR |= BIT(pin + 16);
+		} else {
+			regs->OUTDR &= ~(1 << pin);
+			if (pins->bias_pull_up) {
+				regs->BSHR = BIT(pin);
+			}
+			if (pins->bias_pull_down) {
+				regs->BCR = BIT(pin);
+			}
+		}
+
+		if (bit0 == CH32V003_PINMUX_I2C1_RM) {
+			pcfr1 |= ((remap & 1) << CH32V003_PINMUX_I2C1_RM) |
+				 (((remap >> 1) & 1) << CH32V003_PINMUX_I2C1_RM1);
+		} else if (bit0 == CH32V003_PINMUX_USART1_RM) {
+			pcfr1 |= ((remap & 1) << CH32V003_PINMUX_USART1_RM) |
+				 (((remap >> 1) & 1) << CH32V003_PINMUX_USART1_RM1);
+		} else {
+			pcfr1 |= remap << bit0;
+		}
+		AFIO->PCFR1 = pcfr1;
+	}
+
+	return 0;
+}

drivers/serial/CMakeLists.txt

@@ -73,6 +73,7 @@ zephyr_library_sources_ifdef(CONFIG_UART_STELLARIS uart_stellaris.c)
 zephyr_library_sources_ifdef(CONFIG_UART_STM32 uart_stm32.c)
 zephyr_library_sources_ifdef(CONFIG_UART_SY1XX uart_sy1xx.c)
 zephyr_library_sources_ifdef(CONFIG_UART_TELINK_B91 uart_b91.c)
+zephyr_library_sources_ifdef(CONFIG_UART_WCH_USART uart_wch_usart.c)
 zephyr_library_sources_ifdef(CONFIG_UART_XEC uart_mchp_xec.c)
 zephyr_library_sources_ifdef(CONFIG_UART_XEN_HVC uart_hvc_xen.c)
 zephyr_library_sources_ifdef(CONFIG_UART_XEN_HVC_CONSOLEIO uart_hvc_xen_consoleio.c)

drivers/serial/Kconfig

@@ -221,4 +221,6 @@ rsource "Kconfig.xmc4xxx"
 
 source "drivers/serial/Kconfig.si32"
 
+source "drivers/serial/Kconfig.wch_usart"
+
 endif # SERIAL

drivers/serial/Kconfig.wch_usart

@@ -0,0 +1,11 @@
+# Copyright (c) 2024 Google LLC.
+# SPDX-License-Identifier: Apache-2.0
+
+config UART_WCH_USART
+	bool "CH32V00x USART driver"
+	default y
+	depends on DT_HAS_WCH_USART_ENABLED
+	select SERIAL_HAS_DRIVER
+	select PINCTRL
+	help
+	  This option enables the USART driver for CH32V00x SoC family.

drivers/serial/uart_wch_usart.c

@@ -0,0 +1,140 @@
+/*
+ * Copyright (c) 2024 Google LLC.
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#define DT_DRV_COMPAT wch_usart
+
+#include <errno.h>
+
+#include <zephyr/drivers/uart.h>
+#include <zephyr/drivers/clock_control.h>
+#include <zephyr/drivers/pinctrl.h>
+
+#include <ch32_uart.h>
+
+struct usart_wch_config {
+	USART_TypeDef *regs;
+	const struct device *clock_dev;
+	uint32_t current_speed;
+	uint8_t parity;
+	uint8_t clock_id;
+	const struct pinctrl_dev_config *pin_cfg;
+};
+
+struct usart_wch_data {
+};
+
+static int usart_wch_init(const struct device *dev)
+{
+	const struct usart_wch_config *config = dev->config;
+	USART_TypeDef *regs = config->regs;
+	uint32_t ctlr1 = USART_CTLR1_TE | USART_CTLR1_RE | USART_CTLR1_UE;
+	uint32_t clock_rate;
+	clock_control_subsys_t clock_sys = (clock_control_subsys_t *)(uintptr_t)config->clock_id;
+	uint32_t divn;
+	int err;
+
+	clock_control_on(config->clock_dev, clock_sys);
+
+	err = clock_control_get_rate(config->clock_dev, clock_sys, &clock_rate);
+	if (err != 0) {
+		return err;
+	}
+	divn = (clock_rate + config->current_speed / 2) / config->current_speed;
+
+	switch (config->parity) {
+	case UART_CFG_PARITY_NONE:
+		break;
+	case UART_CFG_PARITY_ODD:
+		ctlr1 |= USART_CTLR1_PCE | USART_CTLR1_PS;
+		break;
+	case UART_CFG_PARITY_EVEN:
+		ctlr1 |= USART_CTLR1_PCE;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	regs->BRR = divn;
+	regs->CTLR1 = ctlr1;
+	regs->CTLR2 = 0;
+	regs->CTLR3 = 0;
+
+	err = pinctrl_apply_state(config->pin_cfg, PINCTRL_STATE_DEFAULT);
+	if (err != 0) {
+		return err;
+	}
+
+	return 0;
+}
+
+static int usart_wch_poll_in(const struct device *dev, unsigned char *ch)
+{
+	const struct usart_wch_config *config = dev->config;
+	USART_TypeDef *regs = config->regs;
+
+	if ((regs->STATR & USART_STATR_RXNE) == 0) {
+		return -1;
+	}
+
+	*ch = regs->DATAR;
+	return 0;
+}
+
+static void usart_wch_poll_out(const struct device *dev, unsigned char ch)
+{
+	const struct usart_wch_config *config = dev->config;
+	USART_TypeDef *regs = config->regs;
+
+	while ((regs->STATR & USART_STATR_TXE) == 0) {
+	}
+
+	regs->DATAR = ch;
+}
+
+static int usart_wch_err_check(const struct device *dev)
+{
+	const struct usart_wch_config *config = dev->config;
+	USART_TypeDef *regs = config->regs;
+	uint32_t statr = regs->STATR;
+	enum uart_rx_stop_reason errors = 0;
+
+	if ((statr & USART_STATR_PE) != 0) {
+		errors |= UART_ERROR_PARITY;
+	}
+	if ((statr & USART_STATR_FE) != 0) {
+		errors |= UART_ERROR_FRAMING;
+	}
+	if ((statr & USART_STATR_NE) != 0) {
+		errors |= UART_ERROR_NOISE;
+	}
+	if ((statr & USART_STATR_ORE) != 0) {
+		errors |= UART_ERROR_OVERRUN;
+	}
+
+	return errors;
+}
+
+static const struct uart_driver_api usart_wch_driver_api = {
+	.poll_in = usart_wch_poll_in,
+	.poll_out = usart_wch_poll_out,
+	.err_check = usart_wch_err_check,
+};
+
+#define USART_WCH_INIT(idx)                                                                        \
+	PINCTRL_DT_INST_DEFINE(idx);                                                               \
+	static struct usart_wch_data usart_wch_##idx##_data;                                       \
+	static const struct usart_wch_config usart_wch_##idx##_config = {                          \
+		.regs = (USART_TypeDef *)DT_INST_REG_ADDR(idx),                                    \
+		.current_speed = DT_INST_PROP(idx, current_speed),                                 \
+		.parity = DT_INST_ENUM_IDX_OR(idx, parity, UART_CFG_PARITY_NONE),                  \
+		.clock_dev = DEVICE_DT_GET(DT_INST_CLOCKS_CTLR(idx)),                              \
+		.clock_id = DT_INST_CLOCKS_CELL(idx, id),                                          \
+		.pin_cfg = PINCTRL_DT_INST_DEV_CONFIG_GET(idx),                                    \
+	};                                                                                         \
+	DEVICE_DT_INST_DEFINE(idx, &usart_wch_init, NULL, &usart_wch_##idx##_data,                 \
+			      &usart_wch_##idx##_config, PRE_KERNEL_1,                             \
+			      CONFIG_SERIAL_INIT_PRIORITY, &usart_wch_driver_api);
+
+DT_INST_FOREACH_STATUS_OKAY(USART_WCH_INIT)

drivers/timer/CMakeLists.txt

@@ -11,6 +11,7 @@ zephyr_library_sources_ifdef(CONFIG_ARCV2_TIMER arcv2_timer0.c)
 zephyr_library_sources_ifdef(CONFIG_ARM_ARCH_TIMER arm_arch_timer.c)
 zephyr_library_sources_ifdef(CONFIG_INTEL_ADSP_TIMER intel_adsp_timer.c)
 zephyr_library_sources_ifdef(CONFIG_CC13XX_CC26XX_RTC_TIMER cc13xx_cc26xx_rtc_timer.c)
+zephyr_library_sources_ifdef(CONFIG_CH32V00X_SYSTICK wch_systick_ch32v00x.c)
 zephyr_library_sources_ifdef(CONFIG_CORTEX_M_SYSTICK cortex_m_systick.c)
 zephyr_library_sources_ifdef(CONFIG_ESP32_SYS_TIMER esp32_sys_timer.c)
 zephyr_library_sources_ifdef(CONFIG_GECKO_BURTC_TIMER gecko_burtc_timer.c)

drivers/timer/Kconfig

@@ -70,6 +70,7 @@ source "drivers/timer/Kconfig.arcv2"
 source "drivers/timer/Kconfig.arm_arch"
 source "drivers/timer/Kconfig.cavs"
 source "drivers/timer/Kconfig.cc13xx_cc26xx_rtc"
+source "drivers/timer/Kconfig.wch_ch32v00x"
 source "drivers/timer/Kconfig.cortex_m_systick"
 source "drivers/timer/Kconfig.esp32"
 source "drivers/timer/Kconfig.gecko"

drivers/timer/Kconfig.wch_ch32v00x

@@ -0,0 +1,8 @@
+# Copyright (c) 2024 Michael Hope
+# SPDX-License-Identifier: Apache-2.0
+
+config CH32V00X_SYSTICK
+	bool "CH32V00X systick timer"
+	depends on SOC_CH32V003
+	default y
+	depends on DT_HAS_WCH_SYSTICK_ENABLED

drivers/timer/wch_systick_ch32v00x.c

@@ -0,0 +1,69 @@
+/*
+ * Copyright (c) 2024 Michael Hope
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#define DT_DRV_COMPAT wch_systick
+
+#include <soc.h>
+#include <zephyr/device.h>
+#include <zephyr/drivers/timer/system_timer.h>
+#include <zephyr/irq.h>
+#include <zephyr/kernel.h>
+#include <zephyr/sys/util.h>
+
+#include <ch32_systick.h>
+
+#define STK_SWIE  BIT(31)
+#define STK_STRE  BIT(3)
+#define STK_STCLK BIT(2)
+#define STK_STIE  BIT(1)
+#define STK_STE   BIT(0)
+
+#define STK_CNTIF BIT(0)
+
+#define CYCLES_PER_SEC  sys_clock_hw_cycles_per_sec()
+#define CYCLES_PER_TICK (CYCLES_PER_SEC / CONFIG_SYS_CLOCK_TICKS_PER_SEC)
+
+#define SYSTICK ((SysTick_Type *)(DT_INST_REG_ADDR(0)))
+
+struct ch32v00x_systick_device {
+};
+
+static volatile uint32_t ch32v00x_systick_count;
+
+static void ch32v00x_systick_irq(const struct ch32v00x_systick_device *unused)
+{
+	ARG_UNUSED(unused);
+
+	SYSTICK->SR = 0;
+	ch32v00x_systick_count += CYCLES_PER_TICK; /* Track cycles. */
+	sys_clock_announce(1);                     /* Poke the scheduler. */
+}
+
+uint32_t sys_clock_cycle_get_32(void)
+{
+	return ch32v00x_systick_count + SYSTICK->CNT;
+}
+
+uint32_t sys_clock_elapsed(void)
+{
+	return 0;
+}
+
+static int ch32v00x_systick_init(void)
+{
+	IRQ_CONNECT(DT_INST_IRQN(0), 0, ch32v00x_systick_irq, NULL, 0);
+
+	SYSTICK->SR = 0;
+	SYSTICK->CMP = CYCLES_PER_TICK;
+	SYSTICK->CNT = 0;
+	SYSTICK->CTLR = STK_STRE | STK_STCLK | STK_STIE | STK_STE;
+
+	irq_enable(DT_INST_IRQN(0));
+
+	return 0;
+}
+
+SYS_INIT(ch32v00x_systick_init, PRE_KERNEL_2, CONFIG_SYSTEM_CLOCK_INIT_PRIORITY);

drivers/watchdog/CMakeLists.txt

@@ -45,6 +45,7 @@ zephyr_library_sources_ifdef(CONFIG_WDT_AMBIQ wdt_ambiq.c)
 zephyr_library_sources_ifdef(CONFIG_WDT_XMC4XXX wdt_xmc4xxx.c)
 zephyr_library_sources_ifdef(CONFIG_WWDT_NUMAKER wdt_wwdt_numaker.c)
 zephyr_library_sources_ifdef(CONFIG_WDT_ENE_KB1200 wdt_ene_kb1200.c)
+zephyr_library_sources_ifdef(CONFIG_WDT_IWDG_CH32V00X wdt_iwdg_ch32v00x.c)
 
 zephyr_library_sources_ifdef(CONFIG_WDT_DW wdt_dw.c wdt_dw_common.c)
 zephyr_library_sources_ifdef(CONFIG_WDT_INTEL_ADSP wdt_intel_adsp.c wdt_dw_common.c)

drivers/watchdog/Kconfig

@@ -134,4 +134,6 @@ source "drivers/watchdog/Kconfig.ene"
 
 source "drivers/watchdog/Kconfig.litex"
 
+source "drivers/watchdog/Kconfig.ch32v00x"
+
 endif # WATCHDOG

drivers/watchdog/Kconfig.ch32v00x

@@ -0,0 +1,9 @@
+# Copyright (c) 2024 Google LLC.
+# SPDX-License-Identifier: Apache-2.0
+
+config WDT_IWDG_CH32V00X
+	bool "CH32V00x Independent Watchdog (IWDG) driver"
+	default y
+	depends on DT_HAS_WCH_IWDG_ENABLED
+	help
+	  Enable the Independent Watchdog (IWDG) driver for CH32V00x SOCs.

drivers/watchdog/wdt_iwdg_ch32v00x.c

@@ -0,0 +1,92 @@
+/*
+ * Copyright (c) 2024 Google LLC.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#define DT_DRV_COMPAT wch_iwdg
+
+#include <zephyr/drivers/watchdog.h>
+#include <zephyr/kernel.h>
+#include <zephyr/sys_clock.h>
+#include <errno.h>
+
+#include <ch32_iwdg.h>
+
+static int iwdg_ch32v00x_setup(const struct device *dev, uint8_t options)
+{
+	if (options != 0) {
+		return -ENOTSUP;
+	}
+
+	IWDG->CTLR = CTLR_KEY_Enable;
+
+	return 0;
+}
+
+static int iwdg_ch32v00x_disable(const struct device *dev)
+{
+	return -EPERM;
+}
+
+static int iwdg_ch32v00x_install_timeout(const struct device *dev,
+					 const struct wdt_timeout_cfg *config)
+{
+	/* The IWDT is driven by the 128 kHz LSI oscillator with at least a /4 prescaler. */
+	int prescaler = 0;
+	uint32_t reload = config->window.max * (128 / 4);
+
+	if (config->callback != NULL) {
+		return -ENOTSUP;
+	}
+	if (config->window.min != 0) {
+		return -ENOTSUP;
+	}
+	if ((config->flags & WDT_FLAG_RESET_MASK) != WDT_FLAG_RESET_CPU_CORE) {
+		return -ENOTSUP;
+	}
+
+	for (; reload > IWDG_RL && prescaler < IWDG_PR;) {
+		prescaler++;
+		reload /= 2;
+	}
+	/* The highest prescaler is effectively invalid. Use that to detect a too long timeout. */
+	if (prescaler == IWDG_PR) {
+		return -EINVAL;
+	}
+
+	/* Wait for the watchdog to be idle, unlock it, update, and wait for idle. */
+	while ((IWDG->STATR & (IWDG_RVU | IWDG_PVU)) != 0) {
+	}
+
+	IWDG->CTLR = IWDG_WriteAccess_Enable;
+	IWDG->PSCR = prescaler;
+	IWDG->RLDR = reload;
+
+	while ((IWDG->STATR & (IWDG_RVU | IWDG_PVU)) != 0) {
+	}
+
+	return 0;
+}
+
+static int iwdg_ch32v00x_feed(const struct device *dev, int channel_id)
+{
+	IWDG->CTLR = CTLR_KEY_Reload;
+
+	return 0;
+}
+
+static const struct wdt_driver_api iwdg_ch32v00x_api = {
+	.setup = iwdg_ch32v00x_setup,
+	.disable = iwdg_ch32v00x_disable,
+	.install_timeout = iwdg_ch32v00x_install_timeout,
+	.feed = iwdg_ch32v00x_feed,
+};
+
+static int iwdg_ch32v00x_init(const struct device *dev)
+{
+	return 0;
+}
+
+DEVICE_DT_INST_DEFINE(0, iwdg_ch32v00x_init, NULL, NULL, NULL, PRE_KERNEL_1,
+		      CONFIG_KERNEL_INIT_PRIORITY_DEVICE, &iwdg_ch32v00x_api);

dts/bindings/clock/wch,ch32v00x-hse-clock.yaml

@@ -0,0 +1,8 @@
+# Copyright (c) 2024 Google LLC.
+# SPDX-License-Identifier: Apache-2.0
+
+description: WCH CH32V00x HSE Clock
+
+compatible: "wch,ch32v00x-hse-clock"
+
+include: [fixed-clock.yaml]

dts/bindings/clock/wch,ch32v00x-hsi-clock.yaml

@@ -0,0 +1,8 @@
+# Copyright (c) 2024 Google LLC.
+# SPDX-License-Identifier: Apache-2.0
+
+description: WCH CH32V00x HSI Clock
+
+compatible: "wch,ch32v00x-hsi-clock"
+
+include: [fixed-clock.yaml]

dts/bindings/clock/wch,ch32v00x-pll-clock.yaml

@@ -0,0 +1,16 @@
+# Copyright (c) 2024 Google LLC.
+# SPDX-License-Identifier: Apache-2.0
+
+description: WCH CH32V00x PLL
+
+compatible: "wch,ch32v00x-pll-clock"
+
+include: [clock-controller.yaml, base.yaml]
+
+properties:
+  "#clock-cells":
+    const: 0
+
+  clocks:
+    type: phandle-array
+    required: true

dts/bindings/clock/wch,rcc.yaml

@@ -0,0 +1,15 @@
+# Copyright (c) 2024 Michael Hope
+# SPDX-License-Identifier: Apache-2.0
+
+description: WCH CH32V00x Reset and Clock Control (RCC)
+
+compatible: "wch,rcc"
+
+include: [clock-controller.yaml, base.yaml]
+
+properties:
+  "#clock-cells":
+    const: 1
+
+clock-cells:
+  - id

dts/bindings/gpio/wch,gpio.yaml

@@ -0,0 +1,19 @@
+# Copyright (c) 2024 Michael Hope
+# SPDX-License-Identifier: Apache-2.0
+
+description: WCH CH32V00x General-Purpose Input/Output (GPIO)
+
+compatible: "wch,gpio"
+
+include: [gpio-controller.yaml, base.yaml]
+
+properties:
+  reg:
+    required: true
+
+  "#gpio-cells":
+    const: 2
+
+gpio-cells:
+  - pin
+  - flags

dts/bindings/interrupt-controller/wch,pfic.yaml

@@ -0,0 +1,18 @@
+# Copyright (c) 2024 Michael Hope
+# SPDX-License-Identifier: Apache-2.0
+
+description: WCH CH32V00x Programmable Fast Interrupt Controller (PFIC)
+
+compatible: "wch,pfic"
+
+include: [interrupt-controller.yaml, base.yaml]
+
+properties:
+  reg:
+    required: true
+
+  "#interrupt-cells":
+    const: 1
+
+interrupt-cells:
+  - irq

dts/bindings/pinctrl/wch,afio.yaml

@@ -0,0 +1,52 @@
+# Copyright (c) 2024 Michael Hope
+# SPDX-License-Identifier: Apache-2.0
+
+description: WCH CH32V00x AFIO
+
+compatible: "wch,afio"
+
+include: base.yaml
+
+properties:
+  reg:
+    required: true
+  "#address-cells":
+    required: true
+    const: 1
+  "#size-cells":
+    required: true
+    const: 1
+
+child-binding:
+  description: |
+    Each child node defines the configuration for a particular state.
+  child-binding:
+    description: |
+      The grandchild nodes group pins that share the same pin configuration.
+
+    include:
+      - name: pincfg-node.yaml
+        property-allowlist:
+          - bias-high-impedance
+          - bias-pull-up
+          - bias-pull-down
+          - drive-open-drain
+          - drive-push-pull
+          - output-high
+          - output-low
+
+    properties:
+      slew-rate:
+        type: string
+        default: "max-speed-2mhz"
+        enum:
+          - "max-speed-10mhz"
+          - "max-speed-2mhz"
+          - "max-speed-30mhz"
+
+      pinmux:
+        required: true
+        type: array
+        description: |
+          An array of pins sharing the same group properties. The pins should
+          be defined using pre-defined macros.

dts/bindings/serial/wch,usart.yaml

@@ -0,0 +1,9 @@
+description: WCH CH32V00x UART
+
+compatible: "wch,usart"
+
+include: [uart-controller.yaml, pinctrl-device.yaml]
+
+properties:
+  reg:
+    required: true

dts/bindings/timer/wch,systick.yaml

@@ -0,0 +1,15 @@
+# Copyright (c) 2024 Michael Hope
+# SPDX-License-Identifier: Apache-2.0
+
+description: WCH CH32V00x Systick
+
+compatible: "wch,systick"
+
+include: base.yaml
+
+properties:
+  reg:
+    required: true
+
+  interrupts:
+    required: true

dts/bindings/vendor-prefixes.txt

@@ -722,6 +722,7 @@ vot	Vision Optical Technology Co., Ltd.
 vxt	VXT Ltd
 wand	Wandbord (Technexion)
 waveshare	Waveshare Electronics
+wch	WinChipHead
 wd	Western Digital Corp.
 we	Würth Elektronik GmbH.
 weact	WeAct Studio

dts/bindings/watchdog/wch,iwdg.yaml

@@ -0,0 +1,12 @@
+# Copyright (c) 2024 Google LLC.
+# SPDX-License-Identifier: Apache-2.0
+
+description: CH32V00x Independent Watchdog (IWDG)
+
+compatible: "wch,iwdg"
+
+include: base.yaml
+
+properties:
+  reg:
+    required: true

dts/riscv/wch/ch32v00x.dtsi

@@ -0,0 +1,157 @@
+/*
+ * Copyright (c) 2024 Michael Hope
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <freq.h>
+#include <mem.h>
+#include <zephyr/dt-bindings/gpio/gpio.h>
+#include <zephyr/dt-bindings/i2c/i2c.h>
+#include <zephyr/dt-bindings/clock/ch32v00x-clocks.h>
+
+/ {
+	#address-cells = <1>;
+	#size-cells = <1>;
+
+	cpus {
+		#address-cells = <1>;
+		#size-cells = <0>;
+
+		cpu0: cpu@0 {
+			device_type = "cpu";
+			compatible = "wch,qingke-v2";
+			reg = <0>;
+		};
+	};
+
+	clocks {
+		clk_hse: clk-hse {
+			#clock-cells = <0>;
+			compatible = "wch,ch32v00x-hse-clock";
+			status = "disabled";
+		};
+
+		clk_hsi: clk-hsi {
+			#clock-cells = <0>;
+			compatible = "wch,ch32v00x-hsi-clock";
+			clock-frequency = <DT_FREQ_M(24)>;
+			status = "disabled";
+		};
+
+		clk_lsi: clk-lsi {
+			#clock-cells = <0>;
+			compatible = "fixed-clock";
+			clock-frequency = <DT_FREQ_K(128)>;
+			status = "disabled";
+		};
+
+		pll: pll {
+			#clock-cells = <0>;
+			compatible = "wch,ch32v00x-pll-clock";
+			status = "disabled";
+		};
+	};
+
+	soc {
+		#address-cells = <1>;
+		#size-cells = <1>;
+		compatible = "simple-bus";
+		ranges;
+
+		sram0: memory@20000000 {
+			compatible = "mmio-sram";
+			reg = <0x20000000 0x800>;
+		};
+
+		flash: flash-controller@40022000 {
+			compatible = "wch,ch32v00x-flash-controller";
+			reg = <0x40022000 0x400>;
+
+			#address-cells = <1>;
+			#size-cells = <1>;
+
+			flash0: flash@0 {
+				compatible = "soc-nv-flash";
+				reg = <0 0x4000>;
+			};
+		};
+
+		pfic: interrupt-controller@e000e000 {
+			compatible = "wch,pfic";
+			#address-cells = <0>;
+			#interrupt-cells = <1>;
+			interrupt-controller;
+			reg = <0xe000e000 16>;
+			status = "okay";
+		};
+
+		systick: systimer@e000f000 {
+			compatible = "wch,systick";
+			reg = <0xe000f000 16>;
+			status = "okay";
+			interrupt-parent = <&pfic>;
+			interrupts = <12>;
+		};
+
+		iwdg: watchdog@40003000 {
+			compatible = "wch,iwdg";
+			reg = <0x40003000 16>;
+		};
+
+		pwr: pwr@40007000 {
+			compatible = "wch,pwr";
+			reg = <0x40007000 16>;
+		};
+
+		pinctrl: pin-controller@40010000 {
+			compatible = "wch,afio";
+			reg = <0x40010000 16>;
+			#address-cells = <1>;
+			#size-cells = <1>;
+			status = "okay";
+
+			gpioa: gpio@40010800 {
+				compatible = "wch,gpio";
+				reg = <0x40010800 32>;
+				gpio-controller;
+				#gpio-cells = <2>;
+				ngpios = <8>;
+				clocks = <&rcc CH32V00X_CLOCK_IOPA>;
+			};
+
+			gpioc: gpio@40011000 {
+				compatible = "wch,gpio";
+				reg = <0x40011000 32>;
+				gpio-controller;
+				#gpio-cells = <2>;
+				ngpios = <8>;
+				clocks = <&rcc CH32V00X_CLOCK_IOPC>;
+			};
+
+			gpiod: gpio@40011400 {
+				compatible = "wch,gpio";
+				reg = <0x40011400 32>;
+				gpio-controller;
+				#gpio-cells = <2>;
+				ngpios = <8>;
+				clocks = <&rcc CH32V00X_CLOCK_IOPD>;
+			};
+		};
+
+		usart1: uart@40013800 {
+			compatible = "wch,usart";
+			reg = <0x40013800 16>;
+			clocks = <&rcc CH32V00X_CLOCK_USART1>;
+			interrupt-parent = <&pfic>;
+			interrupts = <32>;
+		};
+
+		rcc: rcc@40021000 {
+			compatible = "wch,rcc";
+			reg = <0x40021000 16>;
+			#clock-cells = <1>;
+			status = "okay";
+		};
+	};
+};

include/zephyr/dt-bindings/clock/ch32v00x-clocks.h

@@ -0,0 +1,42 @@
+/*
+ * Copyright (c) 2024 Michael Hope
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#ifndef __CH32V00X_CLOCKS_H__
+#define __CH32V00X_CLOCKS_H__
+
+#define CH32V00X_AHB_PCENR_OFFSET  0
+#define CH32V00X_APB2_PCENR_OFFSET 1
+#define CH32V00X_APB1_PCENR_OFFSET 2
+
+#define CH32V00X_CLOCK_CONFIG(bus, bit) (((CH32V00X_##bus##_PCENR_OFFSET) << 5) | (bit))
+
+#define CH32V00X_CLOCK_DMA1  CH32V00X_CLOCK_CONFIG(AHB, 0)
+#define CH32V00X_CLOCK_SRAM  CH32V00X_CLOCK_CONFIG(AHB, 2)
+#define CH32V00X_CLOCK_FLITF CH32V00X_CLOCK_CONFIG(AHB, 4)
+#define CH32V00X_CLOCK_CRC   CH32V00X_CLOCK_CONFIG(AHB, 6)
+#define CH32V00X_CLOCK_USB   CH32V00X_CLOCK_CONFIG(AHB, 12)
+
+#define CH32V00X_CLOCK_AFIO   CH32V00X_CLOCK_CONFIG(APB2, 0)
+#define CH32V00X_CLOCK_IOPA   CH32V00X_CLOCK_CONFIG(APB2, 2)
+#define CH32V00X_CLOCK_IOPB   CH32V00X_CLOCK_CONFIG(APB2, 3)
+#define CH32V00X_CLOCK_IOPC   CH32V00X_CLOCK_CONFIG(APB2, 4)
+#define CH32V00X_CLOCK_IOPD   CH32V00X_CLOCK_CONFIG(APB2, 5)
+#define CH32V00X_CLOCK_ADC1   CH32V00X_CLOCK_CONFIG(APB2, 9)
+#define CH32V00X_CLOCK_ADC2   CH32V00X_CLOCK_CONFIG(APB2, 10)
+#define CH32V00X_CLOCK_TIM1   CH32V00X_CLOCK_CONFIG(APB2, 11)
+#define CH32V00X_CLOCK_SPI1   CH32V00X_CLOCK_CONFIG(APB2, 12)
+#define CH32V00X_CLOCK_USART1 CH32V00X_CLOCK_CONFIG(APB2, 14)
+
+#define CH32V00X_CLOCK_TIM2   CH32V00X_CLOCK_CONFIG(APB1, 0)
+#define CH32V00X_CLOCK_TIM3   CH32V00X_CLOCK_CONFIG(APB1, 1)
+#define CH32V00X_CLOCK_WWDG   CH32V00X_CLOCK_CONFIG(APB1, 11)
+#define CH32V00X_CLOCK_USART2 CH32V00X_CLOCK_CONFIG(APB1, 17)
+#define CH32V00X_CLOCK_I2C1   CH32V00X_CLOCK_CONFIG(APB1, 21)
+#define CH32V00X_CLOCK_BKP    CH32V00X_CLOCK_CONFIG(APB1, 27)
+#define CH32V00X_CLOCK_PWR    CH32V00X_CLOCK_CONFIG(APB1, 28)
+#define CH32V00X_CLOCK_USB    CH32V00X_CLOCK_CONFIG(APB1, 23)
+
+#endif

include/zephyr/dt-bindings/pinctrl/ch32v003-pinctrl.h

@@ -0,0 +1,136 @@
+/*
+ * Copyright (c) 2024 Michael Hope
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#ifndef __CH32V003_PINCTRL_H__
+#define __CH32V003_PINCTRL_H__
+
+#define CH32V003_PINMUX_PORT_PA 0
+#define CH32V003_PINMUX_PORT_PC 1
+#define CH32V003_PINMUX_PORT_PD 2
+
+/*
+ * Defines the starting bit for the remap field. Note that the I2C1 and USART1 fields are not
+ * contigious.
+ */
+#define CH32V003_PINMUX_SPI1_RM    0
+#define CH32V003_PINMUX_I2C1_RM    1
+#define CH32V003_PINMUX_I2C1_RM1   23
+#define CH32V003_PINMUX_USART1_RM  2
+#define CH32V003_PINMUX_USART1_RM1 21
+#define CH32V003_PINMUX_TIM1_RM    6
+#define CH32V003_PINMUX_TIM2_RM    8
+
+/* Port number with 0-2 */
+#define CH32V003_PINCTRL_PORT_SHIFT    0
+/* Pin number 0-15 */
+#define CH32V003_PINCTRL_PIN_SHIFT     2
+/* Base remap bit 0-31 */
+#define CH32V003_PINCTRL_RM_BASE_SHIFT 6
+/* Function remapping ID 0-3 */
+#define CH32V003_PINCTRL_RM_SHIFT      11
+
+#define CH32V003_PINMUX_DEFINE(port, pin, rm, remapping)                                           \
+	((CH32V003_PINMUX_PORT_##port << CH32V003_PINCTRL_PORT_SHIFT) |                            \
+	 (pin << CH32V003_PINCTRL_PIN_SHIFT) |                                                     \
+	 (CH32V003_PINMUX_##rm##_RM << CH32V003_PINCTRL_RM_BASE_SHIFT) |                           \
+	 (remapping << CH32V003_PINCTRL_RM_SHIFT))
+
+#define TIM1_ETR_PC5_0  CH32V003_PINMUX_DEFINE(PC, 5, TIM1, 0)
+#define TIM1_ETR_PC5_1  CH32V003_PINMUX_DEFINE(PC, 5, TIM1, 1)
+#define TIM1_ETR_PD4_2  CH32V003_PINMUX_DEFINE(PD, 4, TIM1, 2)
+#define TIM1_ETR_PC2_3  CH32V003_PINMUX_DEFINE(PC, 2, TIM1, 3)
+#define TIM1_CH1_PD2_0  CH32V003_PINMUX_DEFINE(PD, 2, TIM1, 0)
+#define TIM1_CH1_PC6_1  CH32V003_PINMUX_DEFINE(PC, 6, TIM1, 1)
+#define TIM1_CH1_PD2_2  CH32V003_PINMUX_DEFINE(PD, 2, TIM1, 2)
+#define TIM1_CH1_PC4_3  CH32V003_PINMUX_DEFINE(PC, 4, TIM1, 3)
+#define TIM1_CH2_PA1_0  CH32V003_PINMUX_DEFINE(PA, 1, TIM1, 0)
+#define TIM1_CH2_PC7_1  CH32V003_PINMUX_DEFINE(PC, 7, TIM1, 1)
+#define TIM1_CH2_PA1_2  CH32V003_PINMUX_DEFINE(PA, 1, TIM1, 2)
+#define TIM1_CH2_PC7_3  CH32V003_PINMUX_DEFINE(PC, 7, TIM1, 3)
+#define TIM1_CH3_PC3_0  CH32V003_PINMUX_DEFINE(PC, 3, TIM1, 0)
+#define TIM1_CH3_PC0_1  CH32V003_PINMUX_DEFINE(PC, 0, TIM1, 1)
+#define TIM1_CH3_PC3_2  CH32V003_PINMUX_DEFINE(PC, 3, TIM1, 2)
+#define TIM1_CH3_PC5_3  CH32V003_PINMUX_DEFINE(PC, 5, TIM1, 3)
+#define TIM1_CH4_PC4_0  CH32V003_PINMUX_DEFINE(PC, 4, TIM1, 0)
+#define TIM1_CH4_PD3_1  CH32V003_PINMUX_DEFINE(PD, 3, TIM1, 1)
+#define TIM1_CH4_PC4_2  CH32V003_PINMUX_DEFINE(PC, 4, TIM1, 2)
+#define TIM1_CH4_PD4_3  CH32V003_PINMUX_DEFINE(PD, 4, TIM1, 3)
+#define TIM1_BKIN_PC2_0 CH32V003_PINMUX_DEFINE(PC, 2, TIM1, 0)
+#define TIM1_BKIN_PC1_1 CH32V003_PINMUX_DEFINE(PC, 1, TIM1, 1)
+#define TIM1_BKIN_PC2_2 CH32V003_PINMUX_DEFINE(PC, 2, TIM1, 2)
+#define TIM1_BKIN_PC1_3 CH32V003_PINMUX_DEFINE(PC, 1, TIM1, 3)
+#define TIM1_CH1N_PD0_0 CH32V003_PINMUX_DEFINE(PD, 0, TIM1, 0)
+#define TIM1_CH1N_PC3_1 CH32V003_PINMUX_DEFINE(PC, 3, TIM1, 1)
+#define TIM1_CH1N_PD0_2 CH32V003_PINMUX_DEFINE(PD, 0, TIM1, 2)
+#define TIM1_CH1N_PC3_3 CH32V003_PINMUX_DEFINE(PC, 3, TIM1, 3)
+#define TIM1_CH2N_PA2_0 CH32V003_PINMUX_DEFINE(PA, 2, TIM1, 0)
+#define TIM1_CH2N_PC4_1 CH32V003_PINMUX_DEFINE(PC, 4, TIM1, 1)
+#define TIM1_CH2N_PA2_2 CH32V003_PINMUX_DEFINE(PA, 2, TIM1, 2)
+#define TIM1_CH2N_PD2_3 CH32V003_PINMUX_DEFINE(PD, 2, TIM1, 3)
+#define TIM1_CH3N_PD1_0 CH32V003_PINMUX_DEFINE(PD, 1, TIM1, 0)
+#define TIM1_CH3N_PD1_1 CH32V003_PINMUX_DEFINE(PD, 1, TIM1, 1)
+#define TIM1_CH3N_PD1_2 CH32V003_PINMUX_DEFINE(PD, 1, TIM1, 2)
+#define TIM1_CH3N_PC6_3 CH32V003_PINMUX_DEFINE(PC, 6, TIM1, 3)
+
+#define TIM2_ETR_PD4_0 CH32V003_PINMUX_DEFINE(PD, 4, TIM2, 0)
+#define TIM2_ETR_PC5_1 CH32V003_PINMUX_DEFINE(PC, 5, TIM2, 1)
+#define TIM2_ETR_PC1_2 CH32V003_PINMUX_DEFINE(PC, 1, TIM2, 2)
+#define TIM2_ETR_PC1_3 CH32V003_PINMUX_DEFINE(PC, 1, TIM2, 3)
+#define TIM2_CH1_PD4_0 CH32V003_PINMUX_DEFINE(PD, 4, TIM2, 0)
+#define TIM2_CH1_PC5_1 CH32V003_PINMUX_DEFINE(PC, 5, TIM2, 1)
+#define TIM2_CH1_PC1_2 CH32V003_PINMUX_DEFINE(PC, 1, TIM2, 2)
+#define TIM2_CH1_PC1_3 CH32V003_PINMUX_DEFINE(PC, 1, TIM2, 3)
+#define TIM2_CH2_PD3_0 CH32V003_PINMUX_DEFINE(PD, 3, TIM2, 0)
+#define TIM2_CH2_PC2_1 CH32V003_PINMUX_DEFINE(PC, 2, TIM2, 1)
+#define TIM2_CH2_PD3_2 CH32V003_PINMUX_DEFINE(PD, 3, TIM2, 2)
+#define TIM2_CH2_PC7_3 CH32V003_PINMUX_DEFINE(PC, 7, TIM2, 3)
+#define TIM2_CH3_PC0_0 CH32V003_PINMUX_DEFINE(PC, 0, TIM2, 0)
+#define TIM2_CH3_PD2_1 CH32V003_PINMUX_DEFINE(PD, 2, TIM2, 1)
+#define TIM2_CH3_PC0_2 CH32V003_PINMUX_DEFINE(PC, 0, TIM2, 2)
+#define TIM2_CH3_PD6_3 CH32V003_PINMUX_DEFINE(PD, 6, TIM2, 3)
+#define TIM2_CH4_PD7_0 CH32V003_PINMUX_DEFINE(PD, 7, TIM2, 0)
+#define TIM2_CH4_PC1_1 CH32V003_PINMUX_DEFINE(PC, 1, TIM2, 1)
+#define TIM2_CH4_PD7_2 CH32V003_PINMUX_DEFINE(PD, 7, TIM2, 2)
+#define TIM2_CH4_PD5_3 CH32V003_PINMUX_DEFINE(PD, 5, TIM2, 3)
+
+#define USART1_CK_PD4_0  CH32V003_PINMUX_DEFINE(PD, 4, USART1, 0)
+#define USART1_CK_PD7_1  CH32V003_PINMUX_DEFINE(PD, 7, USART1, 1)
+#define USART1_CK_PD7_2  CH32V003_PINMUX_DEFINE(PD, 7, USART1, 2)
+#define USART1_CK_PC5_3  CH32V003_PINMUX_DEFINE(PC, 5, USART1, 3)
+#define USART1_TX_PD5_0  CH32V003_PINMUX_DEFINE(PD, 5, USART1, 0)
+#define USART1_TX_PD0_1  CH32V003_PINMUX_DEFINE(PD, 0, USART1, 1)
+#define USART1_TX_PD6_2  CH32V003_PINMUX_DEFINE(PD, 6, USART1, 2)
+#define USART1_TX_PC0_3  CH32V003_PINMUX_DEFINE(PC, 0, USART1, 3)
+#define USART1_RX_PD6_0  CH32V003_PINMUX_DEFINE(PD, 6, USART1, 0)
+#define USART1_RX_PD1_1  CH32V003_PINMUX_DEFINE(PD, 1, USART1, 1)
+#define USART1_RX_PD5_2  CH32V003_PINMUX_DEFINE(PD, 5, USART1, 2)
+#define USART1_RX_PC1_3  CH32V003_PINMUX_DEFINE(PC, 1, USART1, 3)
+#define USART1_CTS_PD3_0 CH32V003_PINMUX_DEFINE(PD, 3, USART1, 0)
+#define USART1_CTS_PC3_1 CH32V003_PINMUX_DEFINE(PC, 3, USART1, 1)
+#define USART1_CTS_PC6_2 CH32V003_PINMUX_DEFINE(PC, 6, USART1, 2)
+#define USART1_CTS_PC6_3 CH32V003_PINMUX_DEFINE(PC, 6, USART1, 3)
+#define USART1_RTS_PC2_0 CH32V003_PINMUX_DEFINE(PC, 2, USART1, 0)
+#define USART1_RTS_PC2_1 CH32V003_PINMUX_DEFINE(PC, 2, USART1, 1)
+#define USART1_RTS_PC7_2 CH32V003_PINMUX_DEFINE(PC, 7, USART1, 2)
+#define USART1_RTS_PC7_3 CH32V003_PINMUX_DEFINE(PC, 7, USART1, 3)
+
+#define SPI1_NSS_PC1_0  CH32V003_PINMUX_DEFINE(PC, 1, SPI1, 0)
+#define SPI1_NSS_PC0_1  CH32V003_PINMUX_DEFINE(PC, 0, SPI1, 1)
+#define SPI1_SCK_PC5_0  CH32V003_PINMUX_DEFINE(PC, 5, SPI1, 0)
+#define SPI1_SCK_PC5_1  CH32V003_PINMUX_DEFINE(PC, 5, SPI1, 1)
+#define SPI1_MISO_PC7_0 CH32V003_PINMUX_DEFINE(PC, 7, SPI1, 0)
+#define SPI1_MISO_PC7_1 CH32V003_PINMUX_DEFINE(PC, 7, SPI1, 1)
+#define SPI1_MOSI_PC6_0 CH32V003_PINMUX_DEFINE(PC, 6, SPI1, 0)
+#define SPI1_MOSI_PC6_1 CH32V003_PINMUX_DEFINE(PC, 6, SPI1, 1)
+
+#define I2C1_SCL_PC2_0 CH32V003_PINMUX_DEFINE(PC, 2, I2C1, 0)
+#define I2C1_SCL_PD1_1 CH32V003_PINMUX_DEFINE(PD, 1, I2C1, 1)
+#define I2C1_SCL_PC5_2 CH32V003_PINMUX_DEFINE(PC, 5, I2C1, 2)
+#define I2C1_SDA_PC1_0 CH32V003_PINMUX_DEFINE(PC, 1, I2C1, 0)
+#define I2C1_SDA_PD0_1 CH32V003_PINMUX_DEFINE(PD, 0, I2C1, 1)
+#define I2C1_SDA_PC6_2 CH32V003_PINMUX_DEFINE(PC, 6, I2C1, 2)
+
+#endif /* __CH32V003_PINCTRL_H__ */

modules/hal_wch/CMakeLists.txt

@@ -0,0 +1,3 @@
+if(CONFIG_SOC_SERIES_CH32V00X)
+  zephyr_include_directories(${ZEPHYR_HAL_WCH_MODULE_DIR}/ch32v003fun .)
+endif()

modules/hal_wch/Kconfig

@@ -0,0 +1,7 @@
+#
+# Copyright (c) 2024 Dhiru Kholia
+#
+# SPDX-License-Identifier: Apache-2.0
+#
+
+# file is empty and kept as a place holder if/when Kconfig is needed

modules/hal_wch/ch32_gpio.h

@@ -0,0 +1,16 @@
+/*
+ * Copyright (c) 2024 Dhiru Kholia
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#ifndef _CH32_GPIO_H
+#define _CH32_GPIO_H
+
+#ifdef CONFIG_SOC_CH32V003
+#include <ch32v003fun.h>
+#else
+#error "SoC not supported!"
+#endif
+
+#endif

modules/hal_wch/ch32_iwdg.h

@@ -0,0 +1,16 @@
+/*
+ * Copyright (c) 2024 Google LLC.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#ifndef _CH32_IWDG_H
+#define _CH32_IWDG_H
+
+#ifdef CONFIG_SOC_CH32V003
+#include <ch32v003fun.h>
+#else
+#error "SoC not supported!"
+#endif
+
+#endif

modules/hal_wch/ch32_pfic.h

@@ -0,0 +1,16 @@
+/*
+ * Copyright (c) 2024 Dhiru Kholia
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#ifndef _CH32_PFIC_H
+#define _CH32_PFIC_H
+
+#ifdef CONFIG_SOC_CH32V003
+#include <ch32v003fun.h>
+#else
+#error "SoC not supported!"
+#endif
+
+#endif

modules/hal_wch/ch32_pinctrl.h

@@ -0,0 +1,16 @@
+/*
+ * Copyright (c) 2024 Dhiru Kholia
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#ifndef _CH32_PINCTRL_H
+#define _CH32_PINCTRL_H
+
+#ifdef CONFIG_SOC_CH32V003
+#include <ch32v003fun.h>
+#else
+#error "SoC not supported!"
+#endif
+
+#endif

modules/hal_wch/ch32_rcc.h

@@ -0,0 +1,16 @@
+/*
+ * Copyright (c) 2024 Dhiru Kholia
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#ifndef _CH32_RCC_H
+#define _CH32_RCC_H
+
+#ifdef CONFIG_SOC_CH32V003
+#include <ch32v003fun.h>
+#else
+#error "SoC not supported!"
+#endif
+
+#endif

modules/hal_wch/ch32_soc.h

@@ -0,0 +1,16 @@
+/*
+ * Copyright (c) 2024 Dhiru Kholia
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#ifndef _CH32_SOC_H
+#define _CH32_SOC_H
+
+#ifdef CONFIG_SOC_CH32V003
+#include <ch32v003fun.h>
+#else
+#error "SoC not supported!"
+#endif
+
+#endif

modules/hal_wch/ch32_systick.h

@@ -0,0 +1,16 @@
+/*
+ * Copyright (c) 2024 Dhiru Kholia
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#ifndef _CH32_SYSTICK_H
+#define _CH32_SYSTICK_H
+
+#ifdef CONFIG_SOC_CH32V003
+#include <ch32v003fun.h>
+#else
+#error "SoC not supported!"
+#endif
+
+#endif

modules/hal_wch/ch32_uart.h

@@ -0,0 +1,16 @@
+/*
+ * Copyright (c) 2024 Dhiru Kholia
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#ifndef _CH32_UART_H
+#define _CH32_UART_H
+
+#ifdef CONFIG_SOC_CH32V003
+#include <ch32v003fun.h>
+#else
+#error "SoC not supported!"
+#endif
+
+#endif

modules/hal_wch/funconfig.h

@@ -0,0 +1,14 @@
+/*
+ * Copyright (c) 2024 Dhiru Kholia
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#ifndef _FUNCONFIG_H
+#define _FUNCONFIG_H
+
+#ifdef CONFIG_SOC_CH32V003
+#define CH32V003 1
+#endif
+
+#endif

samples/drivers/watchdog/boards/ch32v003evt.overlay

@@ -0,0 +1,15 @@
+/*
+ * Copyright (c) 2024 Google LLC.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+/ {
+	aliases {
+		watchdog0 = &iwdg;
+	};
+};
+
+&iwdg {
+	status = "okay";
+};

scripts/west_commands/runners/__init__.py

@@ -40,6 +40,7 @@ _names = [
     'jlink',
     'linkserver',
     'mdb',
+    'minichlink',
     'misc',
     'native',
     'nios2',

scripts/west_commands/runners/minichlink.py

@@ -0,0 +1,95 @@
+# Copyright (c) 2024 Google LLC.
+#
+# SPDX-License-Identifier: Apache-2.0
+
+"""WCH CH32V00x specific runner."""
+
+import argparse
+
+from runners.core import ZephyrBinaryRunner, RunnerCaps, RunnerConfig
+
+
+class MiniChLinkBinaryRunner(ZephyrBinaryRunner):
+    """Runner for CH32V00x based devices using minichlink."""
+
+    def __init__(
+        self,
+        cfg: RunnerConfig,
+        minichlink: str,
+        erase: bool,
+        reset: bool,
+        dt_flash: bool,
+        terminal: bool,
+    ):
+        super().__init__(cfg)
+
+        self.minichlink = minichlink
+        self.erase = erase
+        self.reset = reset
+        self.dt_flash = dt_flash
+        self.terminal = terminal
+
+    @classmethod
+    def name(cls):
+        return "minichlink"
+
+    @classmethod
+    def capabilities(cls) -> RunnerCaps:
+        return RunnerCaps(commands={"flash"}, flash_addr=True, erase=True, reset=True)
+
+    @classmethod
+    def do_add_parser(cls, parser: argparse.ArgumentParser):
+        parser.add_argument(
+            "--minichlink", default="minichlink", help="path to the minichlink binary"
+        )
+        parser.add_argument(
+            "--terminal",
+            default=False,
+            action=argparse.BooleanOptionalAction,
+            help="open the terminal after flashing. Implies --reset.",
+        )
+        parser.set_defaults(reset=True)
+
+    @classmethod
+    def do_create(cls, cfg: RunnerConfig, args: argparse.Namespace):
+        return MiniChLinkBinaryRunner(
+            cfg,
+            minichlink=args.minichlink,
+            erase=args.erase,
+            reset=args.reset,
+            dt_flash=(args.dt_flash == "y"),
+            terminal=args.terminal,
+        )
+
+    def do_run(self, command: str, **kwargs):
+        self.require(self.minichlink)
+
+        if command == "flash":
+            self.flash()
+        else:
+            raise ValueError("BUG: unhandled command f{command}")
+
+    def flash(self):
+        self.ensure_output("bin")
+
+        cmd = [self.minichlink, "-a"]
+
+        if self.erase:
+            cmd.append("-E")
+
+        flash_addr = 0
+        if self.dt_flash:
+            flash_addr = self.flash_address_from_build_conf(self.build_conf)
+
+        cmd.extend(["-w", self.cfg.bin_file or "", f"0x{flash_addr:x}"])
+
+        if self.reset or self.terminal:
+            cmd.append("-b")
+
+        if self.terminal:
+            cmd.append("-T")
+
+        if self.terminal:
+            self.check_call(cmd)
+        else:
+            self.check_output(cmd)

scripts/west_commands/tests/test_imports.py

@@ -31,6 +31,7 @@ def test_runner_imports():
         'linkserver',
         'mdb-hw',
         'mdb-nsim',
+        'minichlink',
         'misc-flasher',
         'native',
         'nios2',

soc/wch/ch32v00x/CMakeLists.txt

@@ -0,0 +1,9 @@
+# Copyright (c) 2024 Michael Hope
+# SPDX-License-Identifier: Apache-2.0
+
+zephyr_sources(
+  soc_irq.S
+  vector.S
+)
+
+set(SOC_LINKER_SCRIPT ${ZEPHYR_BASE}/include/zephyr/arch/riscv/common/linker.ld CACHE INTERNAL "")

soc/wch/ch32v00x/Kconfig

@@ -0,0 +1,13 @@
+# Copyright (c) 2024 Michael Hope
+# SPDX-License-Identifier: Apache-2.0
+
+config SOC_CH32V003
+	select RISCV
+	select BUILD_OUTPUT_HEX
+	select RISCV_ISA_RV32E
+	select RISCV_ISA_EXT_ZICSR
+	select RISCV_ISA_EXT_ZIFENCEI
+	select RISCV_ISA_EXT_C
+	select CH32V00X_SYSTICK
+	select ATOMIC_OPERATIONS_C
+	imply XIP

soc/wch/ch32v00x/Kconfig.defconfig

@@ -0,0 +1,24 @@
+# Copyright (c) 2024 Michael Hope
+# SPDX-License-Identifier: Apache-2.0
+
+if SOC_CH32V003
+
+config NUM_IRQS
+	default 48
+
+config SYS_CLOCK_HW_CYCLES_PER_SEC
+	default 48000000
+
+config MAIN_STACK_SIZE
+	default 512
+
+config IDLE_STACK_SIZE
+	default 256
+
+config ISR_STACK_SIZE
+	default 256
+
+config CLOCK_CONTROL
+	default y
+
+endif # SOC_CH32V003

soc/wch/ch32v00x/Kconfig.soc

@@ -0,0 +1,15 @@
+# Copyright (c) 2024 Michael Hope
+# SPDX-License-Identifier: Apache-2.0
+
+config SOC_SERIES_CH32V00X
+	bool
+
+config SOC_CH32V003
+	bool
+	select SOC_SERIES_CH32V00X
+
+config SOC_SERIES
+	default "ch32v00x" if SOC_SERIES_CH32V00X
+
+config SOC
+	default "ch32v003" if SOC_CH32V003

soc/wch/ch32v00x/pinctrl_soc.h

@@ -0,0 +1,42 @@
+/*
+ * Copyright (c) 2024 Michael Hope
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#ifndef __PINCTRL_SOC_H__
+#define __PINCTRL_SOC_H__
+
+/**
+ * @brief Type to hold a pin's pinctrl configuration.
+ */
+struct ch32v003_pinctrl_soc_pin {
+	uint32_t config: 22;
+	bool bias_pull_up: 1;
+	bool bias_pull_down: 1;
+	bool drive_open_drain: 1;
+	bool drive_push_pull: 1;
+	bool output_high: 1;
+	bool output_low: 1;
+	uint8_t slew_rate: 2;
+};
+
+typedef struct ch32v003_pinctrl_soc_pin pinctrl_soc_pin_t;
+
+#define Z_PINCTRL_STATE_PIN_INIT(node_id, prop, idx)                                               \
+	{                                                                                          \
+		.config = DT_PROP_BY_IDX(node_id, prop, idx),                                      \
+		.bias_pull_up = DT_PROP(node_id, bias_pull_up),                                    \
+		.bias_pull_down = DT_PROP(node_id, bias_pull_down),                                \
+		.drive_open_drain = DT_PROP(node_id, drive_open_drain),                            \
+		.drive_push_pull = DT_PROP(node_id, drive_push_pull),                              \
+		.output_high = DT_PROP(node_id, output_high),                                      \
+		.output_low = DT_PROP(node_id, output_low),                                        \
+		.slew_rate = DT_ENUM_IDX(node_id, slew_rate),                                      \
+	},
+
+#define Z_PINCTRL_STATE_PINS_INIT(node_id, prop)                                                   \
+	{DT_FOREACH_CHILD_VARGS(DT_PHANDLE(node_id, prop), DT_FOREACH_PROP_ELEM, pinmux,           \
+				Z_PINCTRL_STATE_PIN_INIT)}
+
+#endif

soc/wch/ch32v00x/soc.h

@@ -0,0 +1,14 @@
+/*
+ * Copyright (c) 2024 Michael Hope
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#ifndef __SOC_H__
+#define __SOC_H__
+
+#ifndef _ASMLANGUAGE
+#include <zephyr/types.h>
+#endif /* !_ASMLANGUAGE */
+
+#endif /* __SOC_H__ */

soc/wch/ch32v00x/soc.yml

@@ -0,0 +1,7 @@
+# Copyright (c) 2024 Michael Hope
+# SPDX-License-Identifier: Apache-2.0
+
+series:
+  - name: ch32v00x
+    socs:
+      - name: ch32v003

soc/wch/ch32v00x/soc_irq.S

@@ -0,0 +1,19 @@
+/* Copyright (c) 2024 Michael Hope
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <offsets.h>
+#include <zephyr/toolchain.h>
+
+/* Exports */
+GTEXT(__soc_is_irq)
+GTEXT(__soc_handle_irq)
+
+SECTION_FUNC(exception.other, __soc_is_irq)
+	csrr a0, mcause
+	srli a0, a0, 31
+	ret
+
+SECTION_FUNC(exception.other, __soc_handle_irq)
+	ret

soc/wch/ch32v00x/vector.S

@@ -0,0 +1,25 @@
+/*
+ * Copyright (c) 2024 Michael Hope
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <zephyr/toolchain.h>
+
+/* Exports */
+GTEXT(__start)
+
+/* Imports */
+GTEXT(__initialize)
+
+SECTION_FUNC(vectors, ivt)
+	.option norvc
+	j       __start
+	.rept 38
+	.word	_isr_wrapper
+	.endr
+
+SECTION_FUNC(vectors, __start)
+	li 	a0, 3
+	csrw	mtvec, a0
+	j	__initialize

west.yml

@@ -247,6 +247,11 @@ manifest:
       path: modules/hal/ti
       groups:
         - hal
+    - name: hal_wch
+      revision: 1de9d3e406726702ce7cfc504509a02ecc463554
+      path: modules/hal/wch
+      groups:
+        - hal
     - name: hal_wurthelektronik
       revision: e3e2797b224fc48fdef1bc3e5a12a7c73108bba2
       path: modules/hal/wurthelektronik