boards/arm: Add Raspberry Pi Pico board support

boards/Kconfig

@@ -1296,6 +1296,12 @@ config ARCH_BOARD_INTEL64_QEMU
 		Port of NuttX to QEMU in intel64 mode.  This port will also run on real
 		generic Intel64 hardware.
 
+config ARCH_BOARD_RASPBERRYPI_PICO
+	bool "Raspberry Pi Pico board"
+	depends on ARCH_CHIP_RP2040
+	---help---
+		This is a port to the Raspberry Pi Pico board.
+
 config ARCH_BOARD_RX65N
 	bool "RX65N renesas board"
 	depends on ARCH_CHIP_R5F565NEDDFC
@@ -2329,6 +2335,7 @@ config ARCH_BOARD
 	default "pic32mz-starterkit"       if ARCH_BOARD_PIC32MZ_STARTERKIT
 	default "qemu-i486"                if ARCH_BOARD_QEMU_I486
 	default "intel64-qemu"             if ARCH_BOARD_INTEL64_QEMU
+	default "raspberrypi-pico"         if ARCH_BOARD_RASPBERRYPI_PICO
 	default "rx65n"                    if ARCH_BOARD_RX65N
 	default "rx65n-rsk1mb"             if ARCH_BOARD_RX65N_RSK1MB
 	default "rx65n-rsk2mb"             if ARCH_BOARD_RX65N_RSK2MB
@@ -2637,6 +2644,9 @@ endif
 if ARCH_BOARD_NUTINY_NUC120
 source "boards/arm/nuc1xx/nutiny-nuc120/Kconfig"
 endif
+if ARCH_BOARD_RASPBERRYPI_PICO
+source "boards/arm/rp2040/raspberrypi-pico/Kconfig"
+endif
 if ARCH_BOARD_ARDUINO_DUE
 source "boards/arm/sam34/arduino-due/Kconfig"
 endif

boards/arm/rp2040/raspberrypi-pico/Kconfig

@@ -0,0 +1,29 @@
+#
+# For a description of the syntax of this configuration file,
+# see the file kconfig-language.txt in the NuttX tools repository.
+#
+
+if ARCH_BOARD_RASPBERRYPI_PICO
+
+config RP2040_FLASH_BOOT
+	bool "flash boot"
+	default y
+	---help---
+		If y, the built binary can be used for flash boot.
+		If not, the binary is for SRAM boot.
+
+config RP2040_FLASH_CHIP
+	string "flash chip name"
+	default "w25q080"
+	---help---
+		Name of NOR flash device connected to RP2040 SoC.
+		(Used to choose the secondary boot loader.)
+		Basically this option should not be changed.
+
+config RP2040_UF2_BINARY
+	bool "uf2 binary format"
+	default y
+	---help---
+		Create nuttx.uf2 binary format used on RP2040 based arch.
+
+endif

boards/arm/rp2040/raspberrypi-pico/README.txt

@@ -0,0 +1,61 @@
+README
+======
+
+This directory contains the port of NuttX to the Raspberry Pi Pico.
+See https://www.raspberrypi.org/products/raspberry-pi-pico/ for information
+about Raspberry Pi Pico.
+
+Currently only the following devices are suppored.
+
+  Supported:
+  - UART  (console port)
+    - GPIO 0 (UART0 TX) and GPIO 1 (UART0 RX) are used for the console.
+  - Flash ROM Boot
+  - SRAM Boot
+    - If Pico SDK is available, nuttx.uf2 file which can be used in
+      BOOTSEL mode will be created.
+
+  Not supported:
+  - All other devices
+
+Installation
+============
+
+1. Download Raspberry Pi Pico SDK
+
+  $ git clone -b master https://github.com/raspberrypi/pico-sdk.git
+
+2. Set PICO_SDK_PATH environment variable
+
+  $ export PICO_SDK_PATH=<absolute_path_to_pico-sdk_directory>
+
+3. Configure and build NuttX
+
+  $ git clone https://github.com/apache/incubator-nuttx.git nuttx
+  $ git clone https://github.com/apache/incubator-nuttx-apps.git apps
+  $ cd nuttx
+  $ make distclean
+  $ ./tools/configure.sh raspberrypi-pico:nsh
+  $ make V=1
+
+4. 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.)
+
+5. To access the console, GPIO 0 and 1 pins must be connected to the
+   device such as USB-serial converter.
+
+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/hardware/*.h
+  - These are generated from rp2040.svd originally provided in Pico SDK.

boards/arm/rp2040/raspberrypi-pico/configs/nsh/defconfig

@@ -0,0 +1,49 @@
+#
+# 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_FS_PROCFS_EXCLUDE_ENVIRON 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_NSH_DISABLE_PRINTF is not set
+# CONFIG_NSH_DISABLE_TRUNCATE is not set
+# CONFIG_STANDARD_SERIAL is not set
+CONFIG_ARCH="arm"
+CONFIG_ARCH_BOARD="raspberrypi-pico"
+CONFIG_ARCH_BOARD_RASPBERRYPI_PICO=y
+CONFIG_ARCH_CHIP="rp2040"
+CONFIG_ARCH_CHIP_RP2040=y
+CONFIG_ARCH_RAMVECTORS=y
+CONFIG_ARCH_STACKDUMP=y
+CONFIG_BOARD_LOOPSPERMSEC=2988
+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_MAX_TASKS=8
+CONFIG_NFILE_DESCRIPTORS=6
+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_SDCLONE_DISABLE=y
+CONFIG_START_DAY=9
+CONFIG_START_MONTH=2
+CONFIG_START_YEAR=2021
+CONFIG_SYSLOG_CONSOLE=y
+CONFIG_SYSTEM_NSH=y
+CONFIG_TESTING_OSTEST=y
+CONFIG_UART0_SERIAL_CONSOLE=y
+CONFIG_USER_ENTRYPOINT="nsh_main"

boards/arm/rp2040/raspberrypi-pico/include/board.h

@@ -0,0 +1,108 @@
+/****************************************************************************
+ * boards/arm/rp2040/raspberrypi-pico/include/board.h
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.  The
+ * ASF licenses this file to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance with the
+ * License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ *
+ ****************************************************************************/
+
+#ifndef __BOARDS_ARM_RP2040_RASPBERRYPI_PICO_INCLUDE_BOARD_H
+#define __BOARDS_ARM_RP2040_RASPBERRYPI_PICO_INCLUDE_BOARD_H
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#ifndef __ASSEMBLY__
+# include <stdint.h>
+#endif
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/* Clocking *****************************************************************/
+
+#define MHZ                     1000000
+
+#define BOARD_XOSC_FREQ         (12 * MHZ)
+#define BOARD_PLL_SYS_FREQ      (125 * MHZ)
+#define BOARD_PLL_USB_FREQ      (48 * MHZ)
+
+#define BOARD_REF_FREQ          (12 * MHZ)
+#define BOARD_SYS_FREQ          (125 * MHZ)
+#define BOARD_PERI_FREQ         (125 * MHZ)
+#define BOARD_USB_FREQ          (48 * MHZ)
+#define BOARD_ADC_FREQ          (48 * MHZ)
+#define BOARD_RTC_FREQ          46875
+
+#define BOARD_UART_BASEFREQ     BOARD_PERI_FREQ
+
+#define BOARD_TICK_CLOCK        (1 * MHZ)
+
+/* GPIO definitions *********************************************************/
+
+#define BOARD_GPIO_UART_PIN     0
+#define BOARD_GPIO_LED_PIN      25
+
+/****************************************************************************
+ * Public Types
+ ****************************************************************************/
+
+#ifndef __ASSEMBLY__
+
+/****************************************************************************
+ * Public Data
+ ****************************************************************************/
+
+#undef EXTERN
+#if defined(__cplusplus)
+#define EXTERN extern "C"
+extern "C"
+{
+#else
+#define EXTERN extern
+#endif
+
+/****************************************************************************
+ * Public Function Prototypes
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: rp2040_boardearlyinitialize
+ *
+ * Description:
+ *
+ ****************************************************************************/
+
+void rp2040_boardearlyinitialize(void);
+
+/****************************************************************************
+ * Name: rp2040_boardinitialize
+ *
+ * Description:
+ *
+ ****************************************************************************/
+
+void rp2040_boardinitialize(void);
+
+#undef EXTERN
+#if defined(__cplusplus)
+}
+#endif
+#endif /* __ASSEMBLY__ */
+#endif /* __BOARDS_ARM_RP2040_RASPBERRYPI_PICO_INCLUDE_BOARD_H */

boards/arm/rp2040/raspberrypi-pico/scripts/Make.defs

@@ -0,0 +1,68 @@
+############################################################################
+# boards/arm/rp2040/raspberrypi-pico/scripts/Make.defs
+#
+# Licensed to the Apache Software Foundation (ASF) under one or more
+# contributor license agreements.  See the NOTICE file distributed with
+# this work for additional information regarding copyright ownership.  The
+# ASF licenses this file to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance with the
+# License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+# License for the specific language governing permissions and limitations
+# under the License.
+#
+############################################################################
+
+include $(TOPDIR)/.config
+include $(TOPDIR)/tools/Config.mk
+include $(TOPDIR)/tools/rp2040/Config.mk
+include $(TOPDIR)/arch/arm/src/armv6-m/Toolchain.defs
+
+ifeq ($(CONFIG_RP2040_FLASH_BOOT),y)
+  LDSCRIPT = raspberrypi-pico-flash.ld
+else
+  LDSCRIPT = raspberrypi-pico-sram.ld
+endif
+
+ifeq ($(CONFIG_CYGWIN_WINTOOL),y)
+  ARCHSCRIPT = -T "${shell cygpath -w $(BOARD_DIR)$(DELIM)scripts$(DELIM)$(LDSCRIPT)}"
+else
+  ARCHSCRIPT = -T$(BOARD_DIR)$(DELIM)scripts$(DELIM)$(LDSCRIPT)
+endif
+
+ifeq ($(CONFIG_DEBUG_SYMBOLS),y)
+  ARCHOPTIMIZATION = -g
+endif
+
+ifneq ($(CONFIG_DEBUG_NOOPT),y)
+  ARCHOPTIMIZATION += $(MAXOPTIMIZATION) -fno-strict-aliasing -fno-strength-reduce -fomit-frame-pointer
+endif
+
+ARCHCFLAGS = -fno-builtin
+ARCHCXXFLAGS = -fno-builtin -fno-exceptions -fcheck-new -fno-rtti
+ARCHWARNINGS = -Wall -Wstrict-prototypes -Wshadow -Wundef
+ARCHWARNINGSXX = -Wall -Wshadow -Wundef
+ARCHPICFLAGS = -fpic -msingle-pic-base -mpic-register=r10
+
+CFLAGS := $(ARCHCFLAGS) $(ARCHWARNINGS) $(ARCHOPTIMIZATION) $(ARCHCPUFLAGS) $(ARCHINCLUDES) $(ARCHDEFINES) $(EXTRAFLAGS) -pipe
+CPICFLAGS = $(ARCHPICFLAGS) $(CFLAGS)
+CXXFLAGS := $(ARCHCXXFLAGS) $(ARCHWARNINGSXX) $(ARCHOPTIMIZATION) $(ARCHCPUFLAGS) $(ARCHXXINCLUDES) $(ARCHDEFINES) $(EXTRAFLAGS) -pipe
+CXXPICFLAGS = $(ARCHPICFLAGS) $(CXXFLAGS)
+CPPFLAGS := $(ARCHINCLUDES) $(ARCHDEFINES) $(EXTRAFLAGS)
+AFLAGS := $(CFLAGS) -D__ASSEMBLY__
+
+NXFLATLDFLAGS1 = -r -d -warn-common
+NXFLATLDFLAGS2 = $(NXFLATLDFLAGS1) -T$(TOPDIR)/binfmt/libnxflat/gnu-nxflat-pcrel.ld -no-check-sections
+LDNXFLATFLAGS = -e main -s 2048
+
+ifneq ($(CROSSDEV),arm-nuttx-elf-)
+  LDFLAGS += -nostartfiles -nodefaultlibs
+endif
+ifeq ($(CONFIG_DEBUG_SYMBOLS),y)
+  LDFLAGS += -g
+endif

boards/arm/rp2040/raspberrypi-pico/scripts/raspberrypi-pico-flash.ld

@@ -0,0 +1,112 @@
+/****************************************************************************
+ * boards/arm/rp2040/raspberrypi-pico/scripts/raspberrypi-pico-flash.ld
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.  The
+ * ASF licenses this file to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance with the
+ * License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ *
+ ****************************************************************************/
+
+MEMORY
+{
+  flash (rx) : ORIGIN = 0x10000000, LENGTH = 2048K
+  sram (rwx) : ORIGIN = 0x20000000, LENGTH = 264K
+}
+
+OUTPUT_ARCH(arm)
+EXTERN(_vectors)
+ENTRY(_stext)
+
+SECTIONS
+{
+    .flash_begin : {
+        __flash_binary_start = .;
+    } > flash
+
+    .boot2 : {
+        __boot2_start__ = .;
+        KEEP (*(.boot2))
+        __boot2_end__ = .;
+    } > flash
+
+    .text : {
+        _stext = ABSOLUTE(.);
+        *(.vectors)
+        *(.text .text.*)
+        *(.fixup)
+        *(.gnu.warning)
+        *(.rodata .rodata.*)
+        *(.gnu.linkonce.t.*)
+        *(.glue_7)
+        *(.glue_7t)
+        *(.got)
+        *(.gcc_except_table)
+        *(.gnu.linkonce.r.*)
+        _etext = ABSOLUTE(.);
+    } > flash
+
+    .init_section : {
+        _sinit = ABSOLUTE(.);
+        *(.init_array .init_array.*)
+        _einit = ABSOLUTE(.);
+    } > flash
+
+    .ARM.extab : {
+        *(.ARM.extab*)
+    } > flash
+
+    __exidx_start = ABSOLUTE(.);
+    .ARM.exidx : {
+        *(.ARM.exidx*)
+    } > flash
+    __exidx_end = ABSOLUTE(.);
+
+    _eronly = ABSOLUTE(.);
+
+    .ram_vectors (COPY) : {
+        *(.ram_vectors)
+    } > sram
+
+    .data : {
+        _sdata = ABSOLUTE(.);
+        *(.data .data.*)
+        *(.gnu.linkonce.d.*)
+        CONSTRUCTORS
+        . = ALIGN(4);
+        _edata = ABSOLUTE(.);
+    } > sram AT > flash
+
+    .bss : {
+        _sbss = ABSOLUTE(.);
+        *(.bss .bss.*)
+        *(.gnu.linkonce.b.*)
+        *(COMMON)
+        . = ALIGN(4);
+        _ebss = ABSOLUTE(.);
+    } > sram
+
+    /* Stabs debugging sections. */
+    .stab 0 : { *(.stab) }
+    .stabstr 0 : { *(.stabstr) }
+    .stab.excl 0 : { *(.stab.excl) }
+    .stab.exclstr 0 : { *(.stab.exclstr) }
+    .stab.index 0 : { *(.stab.index) }
+    .stab.indexstr 0 : { *(.stab.indexstr) }
+    .comment 0 : { *(.comment) }
+    .debug_abbrev 0 : { *(.debug_abbrev) }
+    .debug_info 0 : { *(.debug_info) }
+    .debug_line 0 : { *(.debug_line) }
+    .debug_pubnames 0 : { *(.debug_pubnames) }
+    .debug_aranges 0 : { *(.debug_aranges) }
+}

boards/arm/rp2040/raspberrypi-pico/scripts/raspberrypi-pico-sram.ld

@@ -0,0 +1,97 @@
+/****************************************************************************
+ * boards/arm/rp2040/raspberrypi-pico/scripts/raspberrypi-pico-sram.ld
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.  The
+ * ASF licenses this file to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance with the
+ * License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ *
+ ****************************************************************************/
+
+MEMORY
+{
+  sram (rwx) : ORIGIN = 0x20000000, LENGTH = 264K
+}
+
+OUTPUT_ARCH(arm)
+EXTERN(_vectors)
+ENTRY(_stext)
+
+SECTIONS
+{
+    .text : {
+        _stext = ABSOLUTE(.);
+        rp2040_start.o(.text)
+        . = ALIGN(256);
+        *(.vectors)
+        *(.text .text.*)
+        *(.fixup)
+        *(.gnu.warning)
+        *(.rodata .rodata.*)
+        *(.gnu.linkonce.t.*)
+        *(.glue_7)
+        *(.glue_7t)
+        *(.got)
+        *(.gcc_except_table)
+        *(.gnu.linkonce.r.*)
+        _etext = ABSOLUTE(.);
+    } > sram
+
+    .init_section : {
+        _sinit = ABSOLUTE(.);
+        *(.init_array .init_array.*)
+        _einit = ABSOLUTE(.);
+    } > sram
+
+    .ARM.extab : {
+        *(.ARM.extab*)
+    } > sram
+
+    __exidx_start = ABSOLUTE(.);
+    .ARM.exidx : {
+        *(.ARM.exidx*)
+    } > sram
+    __exidx_end = ABSOLUTE(.);
+
+    .data : {
+        _sdata = ABSOLUTE(.);
+        *(.data .data.*)
+        *(.gnu.linkonce.d.*)
+        CONSTRUCTORS
+        . = ALIGN(4);
+        _edata = ABSOLUTE(.);
+    } > sram
+
+    .bss : {
+        _sbss = ABSOLUTE(.);
+        *(.bss .bss.*)
+        *(.gnu.linkonce.b.*)
+        *(COMMON)
+        . = ALIGN(4);
+        _ebss = ABSOLUTE(.);
+    } > sram
+
+    /* Stabs debugging sections. */
+    .stab 0 : { *(.stab) }
+    .stabstr 0 : { *(.stabstr) }
+    .stab.excl 0 : { *(.stab.excl) }
+    .stab.exclstr 0 : { *(.stab.exclstr) }
+    .stab.index 0 : { *(.stab.index) }
+    .stab.indexstr 0 : { *(.stab.indexstr) }
+    .comment 0 : { *(.comment) }
+    .debug_abbrev 0 : { *(.debug_abbrev) }
+    .debug_info 0 : { *(.debug_info) }
+    .debug_line 0 : { *(.debug_line) }
+    .debug_pubnames 0 : { *(.debug_pubnames) }
+    .debug_aranges 0 : { *(.debug_aranges) }
+}

boards/arm/rp2040/raspberrypi-pico/src/Makefile

@@ -0,0 +1,26 @@
+############################################################################
+# boards/arm/rp2040/raspberrypi-pico/src/Makefile
+#
+# Licensed to the Apache Software Foundation (ASF) under one or more
+# contributor license agreements.  See the NOTICE file distributed with
+# this work for additional information regarding copyright ownership.  The
+# ASF licenses this file to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance with the
+# License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+# License for the specific language governing permissions and limitations
+# under the License.
+#
+############################################################################
+
+include $(TOPDIR)/Make.defs
+
+CSRCS = rp2040_boardinitialize.c
+CSRCS += rp2040_appinit.c
+
+include $(TOPDIR)/boards/Board.mk

boards/arm/rp2040/raspberrypi-pico/src/rp2040_appinit.c

@@ -0,0 +1,68 @@
+/****************************************************************************
+ * boards/arm/rp2040/raspberrypi-pico/src/rp2040_appinit.c
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.  The
+ * ASF licenses this file to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance with the
+ * License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+#include <nuttx/board.h>
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+#ifndef OK
+#  define OK 0
+#endif
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: board_app_initialize
+ *
+ * Description:
+ *   Perform application specific initialization.  This function is never
+ *   called directly from application code, but only indirectly via the
+ *   (non-standard) boardctl() interface using the command BOARDIOC_INIT.
+ *
+ * Input Parameters:
+ *   arg - The boardctl() argument is passed to the board_app_initialize()
+ *         implementation without modification.  The argument has no
+ *         meaning to NuttX; the meaning of the argument is a contract
+ *         between the board-specific initialization logic and the
+ *         matching application logic.  The value could be such things as a
+ *         mode enumeration value, a set of DIP switch switch settings, a
+ *         pointer to configuration data read from a file or serial FLASH,
+ *         or whatever you would like to do with it.  Every implementation
+ *         should accept zero/NULL as a default configuration.
+ *
+ * Returned Value:
+ *   Zero (OK) is returned on success; a negated errno value is returned on
+ *   any failure to indicate the nature of the failure.
+ *
+ ****************************************************************************/
+
+int board_app_initialize(uintptr_t arg)
+{
+  return OK;
+}

boards/arm/rp2040/raspberrypi-pico/src/rp2040_boardinitialize.c

@@ -0,0 +1,93 @@
+/****************************************************************************
+ * boards/arm/rp2040/raspberrypi-pico/src/rp2040-boardinitialize.c
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.  The
+ * ASF licenses this file to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance with the
+ * License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <debug.h>
+
+#include <nuttx/board.h>
+#include <arch/board/board.h>
+
+#include "arm_arch.h"
+#include "arm_internal.h"
+
+#include "rp2040_gpio.h"
+#include "hardware/rp2040_pads_bank0.h"
+#include "hardware/rp2040_io_bank0.h"
+#include "hardware/rp2040_sio.h"
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: rp2040_boardearlyinitialize
+ *
+ * Description:
+ *
+ ****************************************************************************/
+
+void rp2040_boardearlyinitialize(void)
+{
+  /* Disable IE on GPIO 26-29 */
+
+  clrbits_reg32(RP2040_PADS_BANK0_GPIO_IE, RP2040_PADS_BANK0_GPIO(26));
+  clrbits_reg32(RP2040_PADS_BANK0_GPIO_IE, RP2040_PADS_BANK0_GPIO(27));
+  clrbits_reg32(RP2040_PADS_BANK0_GPIO_IE, RP2040_PADS_BANK0_GPIO(28));
+  clrbits_reg32(RP2040_PADS_BANK0_GPIO_IE, RP2040_PADS_BANK0_GPIO(29));
+
+  /* Set default UART TX,RX pin */
+
+  rp2040_gpio_set_function(BOARD_GPIO_UART_PIN,
+                           RP2040_IO_BANK0_GPIO_CTRL_FUNCSEL_UART);
+  rp2040_gpio_set_function(BOARD_GPIO_UART_PIN + 1,
+                           RP2040_IO_BANK0_GPIO_CTRL_FUNCSEL_UART);
+
+  /* Set board LED pin */
+
+  rp2040_gpio_set_function(BOARD_GPIO_LED_PIN,
+                           RP2040_IO_BANK0_GPIO_CTRL_FUNCSEL_SIO);
+  putreg32(1 << BOARD_GPIO_LED_PIN, RP2040_SIO_GPIO_OE_SET);
+
+  putreg32(1 << BOARD_GPIO_LED_PIN, RP2040_SIO_GPIO_OUT_SET);
+}
+
+/****************************************************************************
+ * Name: rp2040_boardinitialize
+ *
+ * Description:
+ *
+ ****************************************************************************/
+
+void rp2040_boardinitialize(void)
+{
+}