boards: add weact rp2350b_core

add weact rp2350b board

Signed-off-by: Camille BAUD <mail@massdriver.space>

boards/weact/rp2350b_core/Kconfig.defconfig

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+# Copyright (c) 2026 MASSDRIVER EI (massdriver.space
+# SPDX-License-Identifier: Apache-2.0
+
+if BOARD_RP2350B_CORE
+
+config USB_SELF_POWERED
+	default n
+
+source "boards/common/usb/Kconfig.cdc_acm_serial.defconfig"
+
+endif # BOARD_RP2350B_CORE

boards/weact/rp2350b_core/Kconfig.rp2350b_core

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+# Copyright (c) 2026 MASSDRIVER EI (massdriver.space)
+# SPDX-License-Identifier: Apache-2.0
+
+config BOARD_RP2350B_CORE
+	select SOC_RP2350B_HAZARD3 if BOARD_RP2350B_CORE_RP2350B_HAZARD3
+	select SOC_RP2350B_M33 if BOARD_RP2350B_CORE_RP2350B_M33

boards/weact/rp2350b_core/board.cmake

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+# SPDX-License-Identifier: Apache-2.0
+
+if("${RPI_PICO_DEBUG_ADAPTER}" STREQUAL "")
+  set(RPI_PICO_DEBUG_ADAPTER "cmsis-dap")
+endif()
+
+board_runner_args(openocd --cmd-pre-init "source [find interface/${RPI_PICO_DEBUG_ADAPTER}.cfg]")
+if(CONFIG_ARM)
+  board_runner_args(openocd --cmd-pre-init "source [find target/rp2350.cfg]")
+else()
+  board_runner_args(openocd --cmd-pre-init "source [find target/rp2350-riscv.cfg]")
+endif()
+
+# The adapter speed is expected to be set by interface configuration.
+# The Raspberry Pi's OpenOCD fork doesn't, so match their documentation at
+# https://www.raspberrypi.com/documentation/microcontrollers/debug-probe.html#debugging-with-swd
+board_runner_args(openocd --cmd-pre-init "set_adapter_speed_if_not_set 1000")
+
+board_runner_args(probe-rs "--chip=RP235x")
+
+board_runner_args(jlink "--device=RP2350_M33_0")
+board_runner_args(uf2 "--board-id=RP2350")
+
+include(${ZEPHYR_BASE}/boards/common/openocd.board.cmake)
+include(${ZEPHYR_BASE}/boards/common/probe-rs.board.cmake)
+include(${ZEPHYR_BASE}/boards/common/jlink.board.cmake)
+include(${ZEPHYR_BASE}/boards/common/uf2.board.cmake)

boards/weact/rp2350b_core/board.yml

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+board:
+  name: rp2350b_core
+  full_name: WeAct RP2350B Core
+  vendor: weact
+  socs:
+    - name: rp2350b

boards/weact/rp2350b_core/doc/index.rst

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+.. zephyr:board:: rp2350b_core
+
+Overview
+********
+
+The WeAct RP2350B Core is a barebone development board for the RP2350B microcontroller by raspberry pi.
+It supports running code on either a single Cortex-M33 or a Hazard3 (RISC-V) core.
+
+As with other RP2 boards, there's no support for running any code on the second core.
+
+Hardware
+********
+
+- Dual Cortex-M33 or Hazard3 processors at up to 150MHz
+- 520KB of SRAM, and 16MB of on-board flash memory
+- USB 1.1 with device and host support
+- Low-power sleep and dormant modes
+- Drag-and-drop programming using mass storage over USB
+- 48 multi-function GPIO pins including 8 that can be used for ADC
+- 2 SPI, 2 I2C, 2 UART, One 12-bit 500ksps Analogue to Digital - Converter (ADC) with 8 channels, 24 controllable PWM channels
+- 2 Timer with 4 alarms, 1 AON Timer
+- Temperature sensor
+- 3 Programmable IO (PIO) blocks, 12 state machines total for custom peripheral support
+
+- `rp2350b_core Schematics`_
+
+Supported Features
+==================
+
+.. zephyr:board-supported-hw::
+
+Connections and IOs
+===================
+
+- Blue LED on pin 25.
+- User button on pin 23.
+- It is possible to add a second flash or a PSRAM chip to the back of the board. The CS is Pin 0. This is not currently supported in zephyr.
+
+Programming and Debugging
+*************************
+
+.. zephyr:board-supported-runners::
+
+The overall explanation regarding flashing and debugging is the same as for :zephyr:board:`rpi_pico`.
+See :ref:`rpi_pico_programming_and_debugging` in :zephyr:board:`rpi_pico` documentation. N.b. OpenOCD support requires using Raspberry Pi's forked version of OpenOCD.
+
+Below is an example of building and flashing the :zephyr:code-sample:`blinky` application.
+
+.. zephyr-app-commands::
+    :zephyr-app: samples/basic/blinky
+    :board: rp2350b_core/rp2350b/m33
+    :goals: build flash
+    :flash-args: -r uf2
+
+.. _rp2350b_core Schematics:
+   https://github.com/WeActStudio/WeActStudio.RP2350BCoreBoard/blob/main/HDK/RP2350B_SCH.pdf

boards/weact/rp2350b_core/rp2350b_core-pinctrl.dtsi

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+/*
+ * Copyright (c) 2026 MASSDRIVER EI (massdriver.space)
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <zephyr/dt-bindings/pinctrl/rpi-pico-rp2350b-pinctrl.h>
+
+&pinctrl {
+	uart0_default: uart0_default {
+		group1 {
+			pinmux = <UART0_TX_P32>;
+		};
+
+		group2 {
+			pinmux = <UART0_RX_P33>;
+			input-enable;
+		};
+	};
+
+	i2c0_default: i2c0_default {
+		group1 {
+			pinmux = <I2C0_SDA_P4>, <I2C0_SCL_P5>;
+			input-enable;
+			input-schmitt-enable;
+		};
+	};
+
+	i2c1_default: i2c1_default {
+		group1 {
+			pinmux = <I2C1_SDA_P6>, <I2C1_SCL_P7>;
+			input-enable;
+			input-schmitt-enable;
+		};
+	};
+
+	spi0_default: spi0_default {
+		group1 {
+			pinmux = <SPI0_CSN_P17>, <SPI0_SCK_P18>, <SPI0_TX_P19>;
+		};
+
+		group2 {
+			pinmux = <SPI0_RX_P16>;
+			input-enable;
+		};
+	};
+
+	pwm_ch4b_default: pwm_ch4b_default {
+		group1 {
+			pinmux = <PWM_4B_P25>;
+		};
+	};
+};

boards/weact/rp2350b_core/rp2350b_core.dtsi

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+/*
+ * Copyright (c) 2026 MASSDRIVER EI (massdriver.space)
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <freq.h>
+
+#include <zephyr/dt-bindings/i2c/i2c.h>
+#include <zephyr/dt-bindings/pwm/pwm.h>
+#include <zephyr/dt-bindings/input/input-event-codes.h>
+
+#include "rp2350b_core-pinctrl.dtsi"
+
+/ {
+	chosen {
+		zephyr,sram = &sram0;
+		zephyr,flash = &flash0;
+		zephyr,flash-controller = &qmi;
+		zephyr,code-partition = &slot0_partition;
+		uart,passthrough = &uart0;
+	};
+
+	aliases {
+		watchdog0 = &wdt0;
+	};
+
+	leds {
+		compatible = "gpio-leds";
+
+		led0: led_0 {
+			gpios = <&gpio0 25 GPIO_ACTIVE_HIGH>;
+			label = "LED";
+		};
+	};
+
+	pwm_leds {
+		compatible = "pwm-leds";
+		status = "disabled";
+
+		pwm_led0: pwm_led_0 {
+			pwms = <&pwm 9 PWM_MSEC(20) PWM_POLARITY_NORMAL>;
+			label = "PWM_LED";
+		};
+	};
+
+	buttons {
+		compatible = "gpio-keys";
+
+		button_0: sw0 {
+			gpios = <&gpio0 23 GPIO_ACTIVE_LOW>;
+			zephyr,code = <INPUT_KEY_0>;
+		};
+	};
+
+	aliases {
+		led0 = &led0;
+		pwm-led0 = &pwm_led0;
+		sw0 = &button_0;
+	};
+};
+
+&flash0 {
+	reg = <0x10000000 DT_SIZE_M(16)>;
+	status = "okay";
+
+	partitions {
+		compatible = "fixed-partitions";
+		#address-cells = <0x1>;
+		#size-cells = <0x1>;
+
+		slot0_partition: partition@0 {
+			label = "image-0";
+			reg = <0x0 0x400000>;
+		};
+
+		slot1_partition: partition@400000 {
+			label = "image-1";
+			reg = <0x400000 0x400000>;
+		};
+
+		storage_partition: partition@800000 {
+			label = "storage";
+			reg = <0x800000 0x800000>;
+		};
+	};
+};
+
+&uart0 {
+	current-speed = <115200>;
+	status = "okay";
+	pinctrl-0 = <&uart0_default>;
+	pinctrl-names = "default";
+};
+
+gpio0_lo: &gpio0 {
+	status = "okay";
+};
+
+gpio1: &gpio0_hi {
+	status = "okay";
+};
+
+&spi0 {
+	clock-frequency = <DT_FREQ_M(20)>;
+	pinctrl-0 = <&spi0_default>;
+	pinctrl-names = "default";
+	status = "okay";
+};
+
+&i2c0 {
+	clock-frequency = <I2C_BITRATE_FAST_PLUS>;
+	pinctrl-0 = <&i2c0_default>;
+	pinctrl-names = "default";
+	status = "okay";
+};
+
+&i2c1 {
+	clock-frequency = <I2C_BITRATE_STANDARD>;
+	pinctrl-0 = <&i2c1_default>;
+	pinctrl-names = "default";
+	status = "okay";
+};
+
+&pwm {
+	pinctrl-0 = <&pwm_ch4b_default>;
+	pinctrl-names = "default";
+	divider-int-0 = <255>;
+};
+
+&timer0 {
+	status = "okay";
+};
+
+&wdt0 {
+	status = "okay";
+};
+
+&rng {
+	status = "okay";
+};
+
+zephyr_udc0: &usbd {
+	status = "okay";
+};
+
+#include <../boards/common/usb/cdc_acm_serial.dtsi>

boards/weact/rp2350b_core/rp2350b_core_rp2350b_hazard3.dts

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+/*
+ * Copyright (c) 2025 Andrew Featherstone
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+/dts-v1/;
+
+/* The build system assumes that there's a cpucluster-specific file.
+ *
+ * This file provides composition of the device tree:
+ * 1. The common features of the SoC
+ * 2. Core-specific configuration.
+ * 3. Board-specific configuration.
+ */
+#include <raspberrypi/rpi_pico/rp2350b.dtsi>
+#include <riscv/raspberrypi/hazard3.dtsi>
+#include "rp2350b_core.dtsi"

boards/weact/rp2350b_core/rp2350b_core_rp2350b_hazard3.yaml

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+identifier: rp2350b_core/rp2350b/hazard3
+name: WeAct RP2350B Core (Hazard3)
+type: mcu
+arch: riscv
+flash: 4096
+ram: 520
+toolchain:
+  - zephyr
+supported:
+  - clock
+  - counter
+  - dma
+  - gpio
+  - hwinfo
+  - i2c
+  - pwm
+  - spi
+  - uart
+  - usbd
+  - watchdog

boards/weact/rp2350b_core/rp2350b_core_rp2350b_hazard3_defconfig

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+# This configuration is orthogonal to whether the Cortex-M33 or Hazard3 cores
+# are in use, but Zephyr does not support providing a qualifier-agnostic
+# _defconfig file.
+CONFIG_BUILD_OUTPUT_HEX=y
+CONFIG_BUILD_OUTPUT_UF2=y
+CONFIG_CLOCK_CONTROL=y
+CONFIG_CONSOLE=y
+CONFIG_GPIO=y
+CONFIG_RESET=y
+CONFIG_SERIAL=y
+CONFIG_UART_CONSOLE=y
+CONFIG_UART_INTERRUPT_DRIVEN=y
+CONFIG_USE_DT_CODE_PARTITION=y

boards/weact/rp2350b_core/rp2350b_core_rp2350b_m33.dts

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+/*
+ * Copyright (c) 2024 Andrew Featherstone
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+/dts-v1/;
+
+/* The build system assumes that there's a cpucluster-specific file.
+ *
+ * This file provides composition of the device tree:
+ * 1. The common features of the SoC
+ * 2. Core-specific configuration.
+ * 3. Board-specific configuration.
+ */
+#include <raspberrypi/rpi_pico/rp2350b.dtsi>
+#include <raspberrypi/rpi_pico/m33.dtsi>
+#include "rp2350b_core.dtsi"

boards/weact/rp2350b_core/rp2350b_core_rp2350b_m33.yaml

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+identifier: rp2350b_core/rp2350b/m33
+name: WeAct RP2350B Core (Cortex-M33)
+type: mcu
+arch: arm
+flash: 4096
+ram: 520
+toolchain:
+  - zephyr
+  - gnuarmemb
+supported:
+  - clock
+  - counter
+  - crypto
+  - dma
+  - entropy
+  - gpio
+  - hwinfo
+  - i2c
+  - pwm
+  - spi
+  - uart
+  - usbd
+  - watchdog

boards/weact/rp2350b_core/rp2350b_core_rp2350b_m33_defconfig

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+# This configuration is orthogonal to whether the Cortex-M33 or Hazard3 cores
+# are in use, but Zephyr does not support providing a qualifier-agnostic
+# _defconfig file.
+CONFIG_BUILD_OUTPUT_HEX=y
+CONFIG_BUILD_OUTPUT_UF2=y
+CONFIG_CLOCK_CONTROL=y
+CONFIG_CONSOLE=y
+CONFIG_GPIO=y
+CONFIG_RESET=y
+CONFIG_SERIAL=y
+CONFIG_UART_CONSOLE=y
+CONFIG_UART_INTERRUPT_DRIVEN=y
+CONFIG_USE_DT_CODE_PARTITION=y

boards/weact/rp2350b_core/support/openocd.cfg

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+# Copyright (c) 2024 TOKITA Hiroshi
+# SPDX-License-Identifier: Apache-2.0
+
+# Checking and set 'adapter speed'.
+# Set the adaptor speed, if unset, and given as an argument.
+proc set_adapter_speed_if_not_set { speed } {
+	puts "checking adapter speed..."
+	if { [catch {adapter speed} ret] } {
+		adapter speed $speed
+	}
+}