boards: wch: add support for ch32v003f4p6 development board

Added support for the CH32V003F4P6 Development Board, which
features QingKe RISC-V2A MCU.

Signed-off-by: Andrei-Edward Popa <andrei.popa105@yahoo.com>

boards/wch/ch32v003f4p6_dev_board/CMakeLists.txt

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+# Copyright (c) 2025 Andrei-Edward Popa <andrei.popa105@yahoo.com>.
+# SPDX-License-Identifier: Apache-2.0
+
+zephyr_library()
+zephyr_library_sources(board.c)

boards/wch/ch32v003f4p6_dev_board/Kconfig

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+# Copyright (c) 2025 Andrei-Edward Popa
+# SPDX-License-Identifier: Apache-2.0
+
+config BOARD_CH32V003F4P6_DEV_BOARD
+	select BOARD_LATE_INIT_HOOK

boards/wch/ch32v003f4p6_dev_board/Kconfig.ch32v003f4p6_dev_board

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+# Copyright (c) 2025 Andrei-Edward Popa
+# SPDX-License-Identifier: Apache-2.0
+
+config BOARD_CH32V003F4P6_DEV_BOARD
+	select SOC_CH32V003

boards/wch/ch32v003f4p6_dev_board/board.c

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+/*
+ * Copyright (c) 2025 Andrei-Edward Popa <andrei.popa105@yahoo.com>
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <zephyr/init.h>
+#include <zephyr/drivers/gpio.h>
+
+#include <ch32fun.h>
+
+#define AFIO_SWCFG_MASK    0x07000000
+#define AFIO_SWCFG_SWD_OFF 0x04000000
+
+void board_late_init_hook(void)
+{
+#if DT_NODE_HAS_STATUS_OKAY(DT_NODELABEL(gpiod))
+	const struct device *gpiod = DEVICE_DT_GET(DT_NODELABEL(gpiod));
+	uint32_t pcfr1;
+
+	/*
+	 * PD1 is wired to led and to SWDIO pin.
+	 * If PD1 is not put to ground, change the function to GPIO to use
+	 * the led as a user led.
+	 * If PD1 is put to ground, let the pin as SWDIO pin (default) to be
+	 * able to program the board.
+	 */
+	if (gpio_pin_get(gpiod, 1) == 1) {
+		RCC->APB2PCENR |= RCC_AFIOEN;
+		pcfr1 = AFIO->PCFR1;
+		pcfr1 = (pcfr1 & ~AFIO_SWCFG_MASK) | (AFIO_SWCFG_SWD_OFF & AFIO_SWCFG_MASK);
+		AFIO->PCFR1 = pcfr1;
+	}
+#endif
+}

boards/wch/ch32v003f4p6_dev_board/board.cmake

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+# Copyright (c) 2025 Andrei-Edward Popa
+# SPDX-License-Identifier: Apache-2.0
+
+board_runner_args(minichlink)
+include(${ZEPHYR_BASE}/boards/common/minichlink.board.cmake)
+
+board_runner_args(openocd "--use-elf" "--cmd-reset-halt" "halt")
+include(${ZEPHYR_BASE}/boards/common/openocd.board.cmake)

boards/wch/ch32v003f4p6_dev_board/board.yml

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+board:
+  name: ch32v003f4p6_dev_board
+  full_name: WCH CH32V003F4P6 Development Board
+  vendor: wch
+  socs:
+    - name: ch32v003

boards/wch/ch32v003f4p6_dev_board/ch32v003f4p6_dev_board-pinctrl.dtsi

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+/*
+ * Copyright (c) 2025 Andrei-Edward Popa <andrei.popa105@yahoo.com>
+ * 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/ch32v003f4p6_dev_board/ch32v003f4p6_dev_board.dts

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+/*
+ * Copyright (c) 2025 Andrei-Edward Popa <andrei.popa105@yahoo.com>
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+/dts-v1/;
+
+#include <wch/ch32v0/ch32v003f4p.dtsi>
+#include "ch32v003f4p6_dev_board-pinctrl.dtsi"
+
+/ {
+	model = "ch32v003f4p6_dev_board";
+	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 1 GPIO_ACTIVE_LOW>;
+			label = "LED";
+		};
+	};
+
+	aliases {
+		led0 = &red_led;
+	};
+};
+
+&clk_hsi {
+	status = "okay";
+};
+
+&pll {
+	clocks = <&clk_hsi>;
+	status = "okay";
+};
+
+&rcc {
+	clocks = <&pll>;
+};
+
+&gpiod {
+	status = "okay";
+};
+
+&usart1 {
+	status = "okay";
+	current-speed = <115200>;
+	pinctrl-0 = <&usart1_default>;
+	pinctrl-names = "default";
+};

boards/wch/ch32v003f4p6_dev_board/ch32v003f4p6_dev_board.yaml

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+identifier: ch32v003f4p6_dev_board
+name: WCH CH32V003F4P6 Development Board
+type: mcu
+arch: riscv
+toolchain:
+  - cross-compile
+  - zephyr
+ram: 2
+flash: 16
+supported:
+  - gpio
+  - uart

boards/wch/ch32v003f4p6_dev_board/ch32v003f4p6_dev_board_defconfig

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+# Copyright (c) 2025 Andrei-Edward Popa
+# SPDX-License-Identifier: Apache-2.0
+
+CONFIG_GPIO=y
+
+CONFIG_SERIAL=y
+CONFIG_CONSOLE=y
+CONFIG_UART_CONSOLE=y

boards/wch/ch32v003f4p6_dev_board/doc/index.rst

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+.. zephyr:board:: ch32v003f4p6_dev_board
+
+Overview
+********
+
+The `WCH`_ CH32V003F4P6 Development Board 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 one LED, wired to PD1 and SWIO pins.
+The `WCH webpage on CH32V003`_ contains the processor's information
+and the datasheet.
+
+Hardware
+********
+
+The QingKe 32-bit RISC-V2A processor of the WCH CH32V003F4P6_DEV_BOARD is clocked
+by an internal RC oscillator and runs at 24 MHz.
+
+Supported Features
+==================
+
+.. zephyr:board-supported-hw::
+
+Connections and IOs
+===================
+
+LED
+---
+
+* LED1 (red) = PD1
+
+Programming and Debugging
+*************************
+
+Applications for the ``ch32v003f4p6_dev_board`` 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
+========
+
+SWIO pin is connected to PD1 and also to led on the board. By default, the function
+of PD1 is SWD. To use the led on the board, the function of PD1 is changed to GPIO
+if PD1 is not put to ground (see :zephyr_file:`boards/wch/ch32v003f4p6_dev_board/board.c`).
+In order to be able to reflash the board, if some zephyr application is already loaded
+in flash, power on the board with PD1 put to ground to let PD1 as SWIO. After that,
+reconnect the external debugger SWDIO pin to PD1/SWIO to be able to flash the board
+using the external debugger.
+
+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: ch32v003f4p6_dev_board
+   :goals: build flash
+
+Debugging
+=========
+
+This board can be debugged via OpenOCD or ``minichlink``.
+
+Testing the LED on the WCH CH32V003F4P6_DEV_BOARD
+*************************************************
+
+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 definition can be found
+in :zephyr_file:`boards/wch/ch32v003f4p6_dev_board/ch32v003f4p6_dev_board.dts`.
+
+References
+**********
+
+.. target-notes::
+
+.. _WCH: http://www.wch-ic.com
+.. _WCH webpage on CH32V003: https://www.wch-ic.com/products/CH32V003.html

boards/wch/ch32v003f4p6_dev_board/support/openocd.cfg

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+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"