Apache NuttX is a mature, real-time embedded operating system (RTOS) https://nuttx.apache.org/
Find a file
Marco Casaroli 1d8898d7d6 arch/arm/rp23xx: Restore XIP with the bootrom XIP setup function.
After a flash operation the driver called flash_select_xip_read_mode()
with a fixed EBh quad mode and clock divisor 4, and called
flash_enter_cmd_xip() if it "failed".  But that ROM function returns
void, so the check read a random r0.  The fixed mode and divisor can
also be different from the ones the bootrom found at boot.

The datasheet (5.2.7, 5.4.8.10) and the Pico SDK use a different
method: after a flash boot the bootrom leaves an XIP setup function in
the first 256 bytes of boot RAM.  It restores the read mode and clock
divisor found at boot.  Boot RAM is not executable, so copy the
function to SRAM once at initialization, and call the copy.

If boot RAM is empty (no flash boot), use flash_enter_cmd_xip(), as
RP23XX_FLASH_MTD_SAFE_XIP does.

Assisted-by: Claude Code:claude-opus-5-5
Signed-off-by: Marco Casaroli <marco.casaroli@gmail.com>
2026-10-07 18:45:43 -03:00
.github build(deps): bump docker/setup-buildx-action from 4.3.0 to 4.4.1 2026-09-21 16:28:50 +08:00
arch arch/arm/rp23xx: Restore XIP with the bootrom XIP setup function. 2026-10-07 18:45:43 -03:00
audio audio: limit the buffer count guard to shared ring requests 2026-08-05 07:58:53 +02:00
binfmt binfmt: Update the TLS pid when exec() swaps the pids. 2026-10-07 21:55:25 +08:00
boards arch/arm/rp23xx: Add RTC alarm support on the POWMAN always-on timer. 2026-10-07 16:22:56 -03:00
cmake cmake/nuttx_add_romfs.cmake: Improved process_all_directory_romfs function 2026-10-05 18:42:56 +08:00
crypto crypto: fix chacha constants under GCC 15. 2026-09-20 08:22:11 -03:00
Documentation arch/arm/rp23xx: Restore XIP with the bootrom XIP setup function. 2026-10-07 18:45:43 -03:00
drivers drivers/net{e1000|igb|igc}: add support for NET_BROADCAST 2026-10-07 13:03:16 +08:00
dummy
fs fs/smartfs: mask reserved flags from stat mode. 2026-10-07 13:28:02 -03:00
graphics graphics/nxterm: consume SGR escape sequences 2026-08-23 10:46:02 +08:00
include libs/libc/elf: Load the libraries a module names in DT_NEEDED. 2026-10-06 17:48:49 -03:00
libs libs/libc/elf: Lay out the PLT of an FDPIC module as the linker expects. 2026-10-07 11:45:09 -03:00
mm mm/iob: fix CONFIG_NET_TIMESTAMPING typo in iob_alloc 2026-09-19 16:36:47 -03:00
net net/netdev: add NETDEV_TX_STAMP and handle SIOCETHTOOL ETHTOOL_GET_TS_INFO 2026-09-28 12:53:24 -03:00
openamp cmake: Use NUTTX(_DIR/_BIN_DIR) instead CMAKE(_SRC_DIR/_BIN_DIR) 2026-08-09 11:13:08 -03:00
pass1 tools: fix stale archive members surviving a Kconfig-driven CSRCS change 2026-07-28 21:26:03 -03:00
sched sched: Skip wd_cancel() on wakeup when the waiter set no timeout. 2026-10-05 20:17:02 +08:00
syscall fs: add chroot() syscall 2026-09-20 22:27:38 +08:00
tools tools/nxflat: Leave ARM unwind tables out of an NXFLAT module. 2026-09-28 16:45:09 -03:00
video video/videomode: Fix EDID parsing and formatting of video mode dumps 2026-08-29 11:09:11 -03:00
wireless wireless/bluetooth: Validate Number Of Completed Packets event. 2026-09-25 10:35:51 +02:00
.asf.yaml github: master branch protection tune. 2025-05-07 18:37:13 -05:00
.codespell-ignore-lines arch/arm/ra8m1: Add GPT timer support 2026-10-01 23:12:10 +08:00
.codespellrc zbus: Add linker support and documentation for the zbus port 2026-09-21 08:40:14 -03:00
.editorconfig .editorconfig: fix character encoding property specification 2025-11-28 19:12:13 +08:00
.gitignore boards/risc-v/eic7700x: Adopt the common board layout. 2026-08-19 01:40:57 +08:00
.gitmessage docs/contributing: Add a commit message template 2025-06-03 17:33:24 +08:00
.mcp.json arch/risc-v/eic7700x: Describe and configure the pads. 2026-09-28 16:19:01 +08:00
.pre-commit-config.yaml
.yamllint
AUTHORS AUTHORS: add Jorge Guzman 2026-08-25 08:43:13 -04:00
CMakeLists.txt cmake: reconfigure when .config changes 2026-09-14 18:40:45 -03:00
CONTRIBUTING.md contributing: Add requirement for 'Assisted-by' commit field 2026-07-12 09:42:28 +08:00
INVIOLABLES.md
Kconfig arm/nrf54l: add Bluetooth SoftDevice Controller support 2026-10-02 15:37:12 -03:00
LICENSE libs/libdsp: Add Matrix operations 2026-07-11 14:55:59 -03:00
Makefile !boards: enforce secure ROMFS passwd and TEA key setup 2026-07-09 22:41:11 +08:00
NOTICE
README.md ci/testing: Add MemBrowse Integration 2026-06-18 12:07:41 -03:00
ReleaseNotes

POSIX Badge License Issues Tracking Badge Contributors GitHub Build Badge Documentation Badge MemBrowse

Apache NuttX is a real-time operating system (RTOS) with an emphasis on standards compliance and small footprint. Scalable from 8-bit to 64-bit microcontroller environments, the primary governing standards in NuttX are POSIX and ANSI standards. Additional standard APIs from Unix and other common RTOSs (such as VxWorks) are adopted for functionality not available under these standards, or for functionality that is not appropriate for deeply-embedded environments (such as fork()).

For brevity, many parts of the documentation will refer to Apache NuttX as simply NuttX.

Getting Started

First time on NuttX? Read the Getting Started guide! If you don't have a board available, NuttX has its own simulator that you can run on terminal.

Documentation

You can find the current NuttX documentation on the Documentation Page.

Alternatively, you can build the documentation yourself by following the Documentation Build Instructions.

The old NuttX documentation is still available in the Apache wiki.

Supported Boards

NuttX supports a wide variety of platforms. See the full list on the Supported Platforms page.

Contributing

If you wish to contribute to the NuttX project, read the Contributing guidelines for information on Git usage, coding standard, workflow and the NuttX principles.

License

The code in this repository is under either the Apache 2 license, or a license compatible with the Apache 2 license. See the License Page for more information.