boards: lilygo: t_oi_plus: initial support

This PR proposes initial support for the Lilygo TTGO T-OI-PLUS ESP32-C3 board, which is largely identical devicetree-wise to the TTGO T8-C3.

Signed-off-by: aisuneko icecat <iceneko@protonmail.ch>

Co-authored-by: Benjamin Cabé <kartben@gmail.com>

boards/lilygo/ttgo_toiplus/Kconfig

@@ -0,0 +1,6 @@
+# Copyright (c) 2024 Espressif Systems (Shanghai) Co., Ltd.
+# SPDX-License-Identifier: Apache-2.0
+
+config HEAP_MEM_POOL_ADD_SIZE_BOARD
+	int
+	default 4096

boards/lilygo/ttgo_toiplus/Kconfig.sysbuild

@@ -0,0 +1,10 @@
+# Copyright (c) 2023 Espressif Systems (Shanghai) Co., Ltd.
+# SPDX-License-Identifier: Apache-2.0
+
+choice BOOTLOADER
+	default BOOTLOADER_MCUBOOT
+endchoice
+
+choice BOOT_SIGNATURE_TYPE
+	default BOOT_SIGNATURE_TYPE_NONE
+endchoice

boards/lilygo/ttgo_toiplus/Kconfig.ttgo_toiplus

@@ -0,0 +1,5 @@
+# Copyright 2025 aisuneko icecat <iceneko@protonmail.ch>
+# SPDX-License-Identifier: Apache-2.0
+
+config BOARD_TTGO_TOIPLUS
+	select SOC_ESP32C3_FN4

boards/lilygo/ttgo_toiplus/board.cmake

@@ -0,0 +1,9 @@
+# SPDX-License-Identifier: Apache-2.0
+
+if(NOT "${OPENOCD}" MATCHES "^${ESPRESSIF_TOOLCHAIN_PATH}/.*")
+  set(OPENOCD OPENOCD-NOTFOUND)
+endif()
+find_program(OPENOCD openocd PATHS ${ESPRESSIF_TOOLCHAIN_PATH}/openocd-esp32/bin NO_DEFAULT_PATH)
+
+include(${ZEPHYR_BASE}/boards/common/esp32.board.cmake)
+include(${ZEPHYR_BASE}/boards/common/openocd.board.cmake)

boards/lilygo/ttgo_toiplus/board.yml

@@ -0,0 +1,6 @@
+board:
+  name: ttgo_toiplus
+  full_name: TTGO T-OI-PLUS
+  vendor: lilygo
+  socs:
+  - name: esp32c3

boards/lilygo/ttgo_toiplus/doc/index.rst

@@ -0,0 +1,199 @@
+.. zephyr:board:: ttgo_toiplus
+
+Overview
+********
+
+Lilygo TTGO T-OI-PLUS is an mini IoT development board based on
+Espressif's ESP32-C3 WiFi/Bluetooth dual-mode chip.
+
+It features the following integrated components:
+
+- ESP32-C3 SoC (RISC-V 160MHz single core, 400KB SRAM, Wi-Fi, Bluetooth)
+- on board Grove connector
+- USB-C connector for power and communication (on board serial)
+- optional 18340 Li-ion battery holder
+- LED
+
+Functional Description
+**********************
+This board is based on the ESP32-C3 with 4MB of flash, WiFi and BLE support. It
+has an USB-C port for programming and debugging, integrated battery charging
+and an Grove connector.
+
+Connections and IOs
+===================
+
+.. zephyr:board-supported-hw::
+
+(Note: the above UART interface also supports connecting through USB.)
+
+Start Application Development
+*****************************
+
+Before powering up your Lilygo TTGO T-OI-PLUS, please make sure that the board is in good
+condition with no obvious signs of damage.
+
+System requirements
+*******************
+
+Prerequisites
+=============
+
+Espressif HAL requires WiFi and Bluetooth binary blobs in order work. Run the command
+below to retrieve those files.
+
+.. code-block:: console
+
+   west blobs fetch hal_espressif
+
+.. note::
+
+   It is recommended running the command above after :file:`west update`.
+
+Building & Flashing
+*******************
+
+Simple boot
+===========
+
+The board could be loaded using the single binary image, without 2nd stage bootloader.
+It is the default option when building the application without additional configuration.
+
+.. note::
+
+   Simple boot does not provide any security features nor OTA updates.
+
+MCUboot bootloader
+==================
+
+User may choose to use MCUboot bootloader instead. In that case the bootloader
+must be built (and flashed) at least once.
+
+There are two options to be used when building an application:
+
+1. Sysbuild
+2. Manual build
+
+.. note::
+
+   User can select the MCUboot bootloader by adding the following line
+   to the board default configuration file.
+
+   .. code:: cfg
+
+      CONFIG_BOOTLOADER_MCUBOOT=y
+
+Sysbuild
+========
+
+The sysbuild makes possible to build and flash all necessary images needed to
+bootstrap the board with the ESP32-C3 SoC.
+
+To build the sample application using sysbuild use the command:
+
+.. zephyr-app-commands::
+   :tool: west
+   :zephyr-app: samples/hello_world
+   :board: ttgo_toiplus
+   :goals: build
+   :west-args: --sysbuild
+   :compact:
+
+By default, the ESP32-C3 sysbuild creates bootloader (MCUboot) and application
+images. But it can be configured to create other kind of images.
+
+Build directory structure created by sysbuild is different from traditional
+Zephyr build. Output is structured by the domain subdirectories:
+
+.. code-block::
+
+  build/
+  ├── hello_world
+  │   └── zephyr
+  │       ├── zephyr.elf
+  │       └── zephyr.bin
+  ├── mcuboot
+  │    └── zephyr
+  │       ├── zephyr.elf
+  │       └── zephyr.bin
+  └── domains.yaml
+
+.. note::
+
+   With ``--sysbuild`` option the bootloader will be re-build and re-flash
+   every time the pristine build is used.
+
+For more information about the system build please read the :ref:`sysbuild` documentation.
+
+Manual build
+============
+
+During the development cycle, it is intended to build & flash as quickly possible.
+For that reason, images can be built one at a time using traditional build.
+
+The instructions following are relevant for both manual build and sysbuild.
+The only difference is the structure of the build directory.
+
+.. note::
+
+   Remember that bootloader (MCUboot) needs to be flash at least once.
+
+Build and flash applications as usual (see :ref:`build_an_application` and
+:ref:`application_run` for more details).
+
+.. zephyr-app-commands::
+   :zephyr-app: samples/hello_world
+   :board: ttgo_toiplus
+   :goals: build
+
+The usual ``flash`` target will work with the ``ttgo_toiplus`` board target.
+Here is an example for the :zephyr:code-sample:`hello_world` application.
+
+.. zephyr-app-commands::
+   :zephyr-app: samples/hello_world
+   :board: ttgo_toiplus
+   :goals: flash
+
+You can also open the serial monitor using the following command:
+
+.. code-block:: shell
+
+   west espressif monitor
+
+After the board has automatically reset and booted, you should see the following
+message in the monitor:
+
+.. code-block:: console
+
+   ***** Booting Zephyr OS vx.x.x-xxx-gxxxxxxxxxxxx *****
+   Hello World! ttgo_toiplus
+
+Sample applications
+===================
+
+The following samples will run out of the box on the TTGO T-OI-PLUS board.
+
+To build the blinky sample:
+
+.. zephyr-app-commands::
+   :tool: west
+   :zephyr-app: samples/basic/blinky
+   :board: ttgo_toiplus
+   :goals: build
+
+To build the bluetooth beacon sample:
+
+.. zephyr-app-commands::
+   :tool: west
+   :zephyr-app: samples/bluetooth/beacon
+   :board: ttgo_toiplus
+   :goals: build
+
+
+Related Documents
+*****************
+.. _`Lilygo TTGO T-OI-PLUS schematic`: https://github.com/Xinyuan-LilyGO/LilyGo-T-OI-PLUS/blob/main/schematic/T-OI_PLUS_Schematic.pdf
+.. _`Lilygo github repo`: https://github.com/Xinyuan-LilyGO
+.. _`Espressif ESP32-C3 datasheet`: https://www.espressif.com/sites/default/files/documentation/esp32-c3_datasheet_en.pdf
+.. _`Espressif ESP32-C3 technical reference manual`: https://www.espressif.com/sites/default/files/documentation/esp32-c3_technical_reference_manual_en.pdf
+.. _`OpenOCD ESP32`: https://github.com/espressif/openocd-esp32/releases

boards/lilygo/ttgo_toiplus/support/openocd.cfg

@@ -0,0 +1,6 @@
+set ESP_RTOS none
+
+source [find interface/esp_usb_jtag.cfg]
+
+source [find target/esp32c3.cfg]
+adapter_khz 5000

boards/lilygo/ttgo_toiplus/ttgo_toiplus-pinctrl.dtsi

@@ -0,0 +1,54 @@
+/*
+ * Copyright 2024 Lothar Felten <lothar.felten@gmail.com>
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <zephyr/dt-bindings/pinctrl/esp-pinctrl-common.h>
+#include <dt-bindings/pinctrl/esp32c3-pinctrl.h>
+#include <zephyr/dt-bindings/pinctrl/esp32c3-gpio-sigmap.h>
+
+&pinctrl {
+	uart0_default: uart0_default {
+		group1 {
+			pinmux = <UART0_TX_GPIO21>;
+			output-high;
+		};
+
+		group2 {
+			pinmux = <UART0_RX_GPIO20>;
+			bias-pull-up;
+		};
+	};
+
+	spim2_default: spim2_default {
+		group1 {
+			pinmux = <SPIM2_MISO_GPIO5>,
+				 <SPIM2_SCLK_GPIO4>;
+		};
+
+		/* GPIO6 is CS */
+
+		group2 {
+			pinmux = <SPIM2_MOSI_GPIO7>;
+			output-low;
+		};
+	};
+
+	i2c0_default: i2c0_default {
+		group1 {
+			pinmux = <I2C0_SDA_GPIO2>,
+				 <I2C0_SCL_GPIO8>;
+			bias-pull-up;
+			drive-open-drain;
+			output-high;
+		};
+	};
+
+	twai_default: twai_default {
+		group1 {
+			pinmux = <TWAI_TX_GPIO0>,
+				 <TWAI_RX_GPIO10>;
+		};
+	};
+};