arm/rp2040: Add support for Waveshare RP2040 Zero board

This change adds a few simple configurations for the Waveshare RP2040 Zero board, along with accompanying documentation.

Documentation/platforms/arm/rp2040/boards/waveshare-rp2040-zero/index.rst

@@ -0,0 +1,234 @@
+===============================
+Waveshare RP2040 Zero
+===============================
+
+The `Waveshare RP2040 Zero <https://www.waveshare.com/wiki/RP2040-Zero>`_ is a general purpose board supplied by
+Waveshare.
+
+.. figure:: WaveshareRP2040Zero.png
+   :align: center
+
+Features
+========
+
+* RP2040 microcontroller chip
+* Dual-core ARM Cortex M0+ processor, flexible clock running up to 133 MHz
+* 264kB of SRAM, and 2MB of on-board Flash memory
+* Castellated module allows soldering direct to carrier boards
+* USB 1.1 Host and Device support
+* Low-power sleep and dormant modes
+* Drag & drop programming using mass storage over USB
+* 20 multi-function GPIO pins
+* 2× SPI, 2× I2C, 2× UART, 3× 12-bit ADC, 16× controllable PWM channels
+* Accurate clock and timer on-chip
+* Temperature sensor
+* Accelerated floating point libraries on-chip
+* 8 × Programmable IO (PIO) state machines for custom peripheral support
+
+Serial Console
+==============
+
+By default a serial console appears on pins 23 (TX GPIO0) and pin 22
+(RX GPIO1).  This console runs a 115200-8N1.
+
+The board can be configured to use the USB connection as the serial console.
+
+Buttons and LEDs
+================
+
+A ws2812 (NeoPixel) smart RGB LED controlled by GPIO16 (data).
+
+There is a BOOT button which if held down when power is first
+applied or the RESET button is pressed will cause the RP2040 to
+boot into program mode and appear as a storage device to
+a USB connecter.  Saving a .UF2 file to this device will
+replace the Flash ROM contents on the RP2040.
+
+Pin Mapping
+===========
+Pads numbered anticlockwise from USB connector.
+
+===== ========== ==========
+Pad   Signal     Notes
+===== ========== ==========
+1     5V
+2     Ground
+3     3.3V
+4     GPIO29
+5     GPIO28
+6     GPIO27
+7     GPIO26
+8     GPIO15
+9     GPIO14
+10    GPIO13
+11    GPIO12
+12    GPIO11     Default TX for SPI1
+13    GPIO10     Default SCK for SPI1
+14    GPIO9      Default CSn for SPI1
+15    GPIO8      Default RX for SPI1
+16    GPIO7      Default SCL for I2C1
+17    GPIO6      Default SDA for I2C1
+18    GPIO5      Default SCL for I2C0
+19    GPIO4      Default SDA for I2C0
+20    GPIO3
+21    GPIO2
+22    GPIO1      Default RX for UART0 serial console
+23    GPIO0      Default TX for UART0 serial console
+===== ========== ==========
+
+
+Power Supply
+============
+
+The Waveshare RP2040 Zero can be powered via the USB connector,
+or by supplying +5V to pin 1.
+
+The RP2040 runs on 3.3 volts.  This is supplied
+by an onboard voltage regulator.
+
+Supported Capabilities
+======================
+
+NuttX supports the following RP2040 capabilities:
+
+* UART  (console port)
+
+  * GPIO 0 (UART0 TX) and GPIO 1 (UART0 RX) are used for the console.
+
+* I2C
+* SPI (master only)
+* DMAC
+* PWM
+* ADC
+* Watchdog
+* USB device
+
+  * MSC, CDC/ACM serial and these composite device are supported.
+  * CDC/ACM serial device can be used for the console.
+
+* PIO (RP2040 Programmable I/O)
+* Flash ROM Boot
+* SRAM Boot
+
+  * If Pico SDK is available, nuttx.uf2 file which can be used in BOOTSEL mode will be created.
+
+* Persistent flash filesystem in unused flash ROM
+* WiFi wireless communication
+
+There is currently no direct user mode access to these RP2040 hardware features:
+
+* SPI Slave Mode
+* SSI
+* RTC
+* Timers
+
+NuttX also provide support for these external devices:
+
+* BMP180 sensor at I2C0 (don't forget to define I2C0 GPIOs at "I2C0 GPIO pin assign" in Board Selection menu)
+* INA219 sensor / module (don't forget to define I2C0 GPIOs at "I2C0 GPIO pin assign" in Board Selection menu)
+* SHT4X sensor at I2C0
+* Pico Display Pack (ST7789 LCD)
+
+  * RGB leds and buttons are not supported yet.
+
+* Pico Audio Pack (PCM5100A I2S DAC)
+
+  * I2S interface is realized by PIO.
+
+* WS2812 smart pixel support
+
+Installation
+============
+
+1. Download Raspberry Pi Pico SDK
+
+.. code-block:: console
+
+  $ git clone -b 2.0.0 https://github.com/raspberrypi/pico-sdk.git
+
+2. Download and install picotool
+
+  Instructions can be found here: https://github.com/raspberrypi/picotool
+
+  If you are on Arch Linux, you can install the picotool through the AUR:
+
+.. code-block:: console
+
+  $ yay -S picotool
+
+3. Set PICO_SDK_PATH environment variable
+
+.. code-block:: console
+
+  $ export PICO_SDK_PATH=<absolute_path_to_pico-sdk_directory>
+
+4. Configure and build NuttX
+
+.. code-block:: console
+
+  $ git clone https://github.com/apache/nuttx.git nuttx
+  $ git clone https://github.com/apache/nuttx-apps.git apps
+  $ cd nuttx
+  $ make distclean
+  $ ./tools/configure.sh waveshare-rp2040-zero:nsh
+  $ make V=1
+
+5. Connect Raspberry Pi Pico board to USB port while pressing BOOTSEL.
+   The board will be detected as USB Mass Storage Device.
+   Then copy "nuttx.uf2" into the device.
+   (Same manner as the standard Pico SDK applications installation.)
+
+6. To access the console, GPIO 0 and 1 pins must be connected to the
+   device such as USB-serial converter.
+
+   `usbnsh` configuration provides the console access by USB CDC/ACM serial
+   device.  The console is available by using a terminal software on the USB
+   host.
+
+
+Configurations
+==============
+
+gpio
+--------
+
+NuttShell configuration (console enabled in UART0, at 115200 bps) with GPIO examples.
+
+nsh
+---
+
+Basic NuttShell configuration (console enabled in UART0, at 115200 bps).
+
+
+usbnsh
+------
+
+Basic NuttShell configuration using CDC/ACM serial (console enabled in USB Port,
+at 115200 bps).
+
+ws2812
+------
+
+Basic NuttShell configuration with WS2812 driver and example enabled. Console is enabled over USB at 115200 bps.
+
+License exceptions
+==================
+
+The following files are originated from the files in Pico SDK.
+So, the files are licensed under 3-Clause BSD same as Pico SDK.
+
+* arch/arm/src/rp2040/rp2040_clock.c
+* arch/arm/src/rp2040/rp2040_pll.c
+* arch/arm/src/rp2040/rp2040_xosc.c
+
+  * These are created by referring the Pico SDK clock initialization.
+
+* arch/arm/src/rp2040/rp2040_pio.c
+* arch/arm/src/rp2040/rp2040_pio.h
+* arch/arm/src/rp2040/rp2040_pio_instructions.h
+
+  * These provide the similar APIs to Pico SDK's hardware_pio APIs.
+
+* arch/arm/src/rp2040/hardware/\*.h
+
+  * These are generated from rp2040.svd originally provided in Pico SDK.

boards/Kconfig

@@ -1967,6 +1967,13 @@ config ARCH_BOARD_W5500_EVB_PICO
 		This is a port to the WIZnet W5500-EVB-Pico board.
 		Support is derived from Raspberry Pi Pico support.
 
+config ARCH_BOARD_WAVESHARE_RP2040_ZERO
+	bool "Waveshare RP2040 Zero board"
+	depends on ARCH_CHIP_RP2040
+	---help---
+		This is a port to the Waveshare RP2040 Zero board.
+		Support is derived from Raspberry Pi Pico support.
+
 config ARCH_BOARD_RX65N
 	bool "RX65N renesas board"
 	depends on ARCH_CHIP_R5F565NEDDFC
@@ -3445,6 +3452,7 @@ config ARCH_BOARD
 	default "adafruit-qt-py-rp2040"     if ARCH_BOARD_ADAFRUIT_QT_PY_RP2040
 	default "waveshare-rp2040-lcd-1.28" if ARCH_BOARD_WAVESHARE_RP2040_LCD_1_28
 	default "w5500-evb-pico"            if ARCH_BOARD_W5500_EVB_PICO
+        default "waveshare-rp2040-zero"     if ARCH_BOARD_WAVESHARE_RP2040_ZERO
 	default "rx65n"                     if ARCH_BOARD_RX65N
 	default "rx65n-rsk1mb"              if ARCH_BOARD_RX65N_RSK1MB
 	default "rx65n-rsk2mb"              if ARCH_BOARD_RX65N_RSK2MB
@@ -3906,6 +3914,9 @@ endif
 if ARCH_BOARD_ADAFRUIT_QT_PY_RP2040
 source "boards/arm/rp2040/adafruit-qt-py-rp2040/Kconfig"
 endif
+if ARCH_BOARD_WAVESHARE_RP2040_ZERO
+source "boards/arm/rp2040/waveshare-rp2040-zero/Kconfig"
+endif
 if ARCH_BOARD_ARDUINO_DUE
 source "boards/arm/sam34/arduino-due/Kconfig"
 endif

boards/arm/rp2040/waveshare-rp2040-zero/Kconfig

@@ -0,0 +1,8 @@
+#
+# For a description of the syntax of this configuration file,
+# see the file kconfig-language.txt in the NuttX tools repository.
+#
+
+if ARCH_BOARD_WAVESHARE_RP2040_ZERO
+
+endif

boards/arm/rp2040/waveshare-rp2040-zero/configs/gpio/defconfig

@@ -0,0 +1,53 @@
+#
+# This file is autogenerated: PLEASE DO NOT EDIT IT.
+#
+# You can use "make menuconfig" to make any modifications to the installed .config file.
+# You can then do "make savedefconfig" to generate a new defconfig file that includes your
+# modifications.
+#
+# CONFIG_DEV_CONSOLE is not set
+# CONFIG_LIBC_LONG_LONG is not set
+# CONFIG_NSH_ARGCAT is not set
+# CONFIG_NSH_CMDOPT_HEXDUMP is not set
+# CONFIG_NSH_DISABLE_DATE is not set
+# CONFIG_NSH_DISABLE_LOSMART is not set
+# CONFIG_RP2040_UART0 is not set
+CONFIG_ARCH="arm"
+CONFIG_ARCH_BOARD="waveshare-rp2040-zero"
+CONFIG_ARCH_BOARD_WAVESHARE_RP2040_ZERO=y
+CONFIG_ARCH_CHIP="rp2040"
+CONFIG_ARCH_CHIP_RP2040=y
+CONFIG_ARCH_RAMVECTORS=y
+CONFIG_ARCH_STACKDUMP=y
+CONFIG_BOARDCTL_RESET=y
+CONFIG_BOARD_LOOPSPERMSEC=10450
+CONFIG_BUILTIN=y
+CONFIG_CDCACM=y
+CONFIG_CDCACM_CONSOLE=y
+CONFIG_DEBUG_FULLOPT=y
+CONFIG_DEBUG_SYMBOLS=y
+CONFIG_DEV_GPIO=y
+CONFIG_DISABLE_POSIX_TIMERS=y
+CONFIG_EXAMPLES_GPIO=y
+CONFIG_EXAMPLES_HELLO=y
+CONFIG_FS_PROCFS=y
+CONFIG_FS_PROCFS_REGISTER=y
+CONFIG_INIT_ENTRYPOINT="nsh_main"
+CONFIG_NFILE_DESCRIPTORS_PER_BLOCK=6
+CONFIG_NSH_ARCHINIT=y
+CONFIG_NSH_BUILTIN_APPS=y
+CONFIG_NSH_READLINE=y
+CONFIG_NSH_USBCONSOLE=y
+CONFIG_RAM_SIZE=270336
+CONFIG_RAM_START=0x20000000
+CONFIG_READLINE_CMD_HISTORY=y
+CONFIG_RR_INTERVAL=200
+CONFIG_SCHED_WAITPID=y
+CONFIG_START_DAY=9
+CONFIG_START_MONTH=2
+CONFIG_START_YEAR=2021
+CONFIG_SYSTEM_NSH=y
+CONFIG_TESTING_GETPRIME=y
+CONFIG_TESTING_OSTEST=y
+CONFIG_USBDEV=y
+CONFIG_USBDEV_BUSPOWERED=y

boards/arm/rp2040/waveshare-rp2040-zero/configs/nsh/defconfig

@@ -0,0 +1,47 @@
+#
+# This file is autogenerated: PLEASE DO NOT EDIT IT.
+#
+# You can use "make menuconfig" to make any modifications to the installed .config file.
+# You can then do "make savedefconfig" to generate a new defconfig file that includes your
+# modifications.
+#
+# CONFIG_LIBC_LONG_LONG is not set
+# CONFIG_NSH_ARGCAT is not set
+# CONFIG_NSH_CMDOPT_HEXDUMP is not set
+# CONFIG_NSH_DISABLE_DATE is not set
+# CONFIG_NSH_DISABLE_LOSMART is not set
+# CONFIG_STANDARD_SERIAL is not set
+CONFIG_ARCH="arm"
+CONFIG_ARCH_BOARD="waveshare-rp2040-zero"
+CONFIG_ARCH_BOARD_WAVESHARE_RP2040_ZERO=y
+CONFIG_ARCH_CHIP="rp2040"
+CONFIG_ARCH_CHIP_RP2040=y
+CONFIG_ARCH_RAMVECTORS=y
+CONFIG_ARCH_STACKDUMP=y
+CONFIG_BOARDCTL_RESET=y
+CONFIG_BOARD_LOOPSPERMSEC=10450
+CONFIG_BUILTIN=y
+CONFIG_DEBUG_FULLOPT=y
+CONFIG_DEBUG_SYMBOLS=y
+CONFIG_DISABLE_POSIX_TIMERS=y
+CONFIG_EXAMPLES_HELLO=y
+CONFIG_FS_PROCFS=y
+CONFIG_FS_PROCFS_REGISTER=y
+CONFIG_INIT_ENTRYPOINT="nsh_main"
+CONFIG_NFILE_DESCRIPTORS_PER_BLOCK=6
+CONFIG_NSH_ARCHINIT=y
+CONFIG_NSH_BUILTIN_APPS=y
+CONFIG_NSH_READLINE=y
+CONFIG_RAM_SIZE=270336
+CONFIG_RAM_START=0x20000000
+CONFIG_READLINE_CMD_HISTORY=y
+CONFIG_RR_INTERVAL=200
+CONFIG_SCHED_WAITPID=y
+CONFIG_START_DAY=9
+CONFIG_START_MONTH=2
+CONFIG_START_YEAR=2021
+CONFIG_SYSLOG_CONSOLE=y
+CONFIG_SYSTEM_NSH=y
+CONFIG_TESTING_GETPRIME=y
+CONFIG_TESTING_OSTEST=y
+CONFIG_UART0_SERIAL_CONSOLE=y