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wangjianyu3 1feb93a5ae boards/esp32s3-devkit: switch defconfigs to nxinit entrypoint
Switch all esp32s3-devkit defconfigs still on nsh_main (adc, audio,
ble, blewifi, buttons, capture, crypto, cxx, efuse, elf, eth_lan9250,
fastboot, fastboot_tcp, gpio, i2c, i2schar, knsh, ksta_softap, mbedtls,
mcuboot_nsh, mcuboot_update_agent, motor, nsh, nxlooper, oneshot,
ostest, pm, psram_octal, psram_quad, psram_usrheap, pwm, python,
qemu_debug, qemu_openeth, qemu_toywasm, qencoder, random, rmt, romfs,
rtc, sdm, sdmmc, sdmmc_spi, smp, sotest, spi, spiflash, spislv,
sta_softap, stack, temperature_sensor, tickless, timer, toywasm, twai,
ulp, usb_device, usbnsh, watchdog, wifi) to nxinit (init_main) as the
system init entry point, matching this board's adb/txtable configs
that already use nxinit, and matching the lckfb-szpi-esp32s3 board
(see 73c949c87e) for consistency across esp32s3 boards.

For each defconfig:
- CONFIG_INIT_ENTRYPOINT switched to "init_main"
- CONFIG_INIT_STACKSIZE set to 8192. Measured on lckfb-szpi-esp32s3
  with CONFIG_STACK_COLORATION=y on the worst case available: a config
  whose init.rc starts two services (console sh + adbd). At the 2048
  Kconfig default the board panics at runtime (xtensa_user_panic, task
  "sh"); at 4096 init_main reaches FILLED=99.5%, i.e. no headroom; at
  8192 it settles at USED=4336 (53.6%). A single-service config only
  fills 46.9% of a 3072-byte init stack, so 8192 is deliberately
  uniform rather than minimal: it covers the two-service worst case
  with roughly 2x margin and keeps every defconfig off the 2048
  default, where the init stack overflows and clobbers the global
  inode/mount tree - the procfs mount disappears, "ls /" crashes in
  read_pseudodir and "ps" reports "/proc not mounted".
- CONFIG_SYSTEM_NXINIT=y added, plus its direct Kconfig dependencies
  (CONFIG_EXPERIMENTAL, CONFIG_LIBC_EXECFUNCS, CONFIG_SCHED_CHILD_STATUS,
  which depends on CONFIG_SCHED_HAVE_PARENT)
- CONFIG_SYSTEM_NSH_STACKSIZE=8192 added: nsh now runs as a service
  spawned by init.rc instead of being init itself, so the shell
  workload is carried by its own stack rather than the init stack.
  Without this it falls back to CONFIG_DEFAULT_TASK_STACKSIZE (2048
  unless the defconfig overrides it) and crashes in getumask while
  running "ps", too small to reach the procfs read path.
  esp32s3-devkit:stack was the only defconfig that already set this
  option (at 4096); it is raised to 8192 with the rest.
- ETC_ROMFS/FS_ROMFS added where missing, needed to ship init.rc via
  the board's ROMFS

nsh continues to run as a console service started by init.rc
(boards/xtensa/esp32s3/common/src/etc/init.d/init.rc), not as the
top-level init, matching this board's existing adb/txtable configs.

Verified 59 of the 60 changed defconfigs build cleanly with make.
esp32s3-devkit:qemu_openeth fails to link on this host both before
and after this change (MERGEBIN error: missing ESPTOOL_BINDIR, a
pre-existing local build-invocation issue unrelated to this patch).
esp32s3-devkit:stack segfaults the linker on this host both before
and after this change (pre-existing toolchain issue on this host,
unrelated to this patch). esp32s3-devkit:ulp fails at context/rule
generation on this host due to a missing local RISC-V ULP toolchain
setup, also unrelated to this patch.

Runtime behavior (init_main spawning nsh as a console service) was
confirmed on lckfb-szpi-esp32s3 hardware, which shares the same
nxinit/init.rc mechanism; this board has no hardware attached for a
flash/boot pass in this session, so the build-verified defconfigs are
the extent of local testing here.

Assisted-by: Kiro:claude-sonnet-5
Assisted-by: Kiro:claude-opus-5
Signed-off-by: wangjianyu3 <wangjianyu3@xiaomi.com>
2026-08-25 11:03:32 -03:00
.github build(deps): bump docker/setup-buildx-action from 4.2.0 to 4.3.0 2026-08-24 15:30:16 +08:00
arch {arm,xtensa}/otg: indent switch bodies per the coding standard. 2026-08-25 16:07:35 +08:00
audio audio: limit the buffer count guard to shared ring requests 2026-08-05 07:58:53 +02:00
binfmt sched: add supplementary group IDs (setgroups/getgroups/initgroups) 2026-08-12 16:06:03 -03:00
boards boards/esp32s3-devkit: switch defconfigs to nxinit entrypoint 2026-08-25 11:03:32 -03:00
cmake sched,fs,docs: support setuid sudo helper 2026-08-18 15:57:52 +08:00
crypto tools: fix stale archive members surviving a Kconfig-driven CSRCS change 2026-07-28 21:26:03 -03:00
Documentation Documentation/stm32h5: LPTIM is supported. 2026-08-25 13:37:44 +08:00
drivers drivers/pci/pci.c: fix nxstyle issues 2026-08-25 01:40:32 +08:00
dummy build: add initial cmake build system 2023-07-08 13:50:48 +08:00
fs nuttx/atomic: replace atomic_fetch_xxx with atomic_xxx just like zephyr 2026-08-24 13:20:45 +08:00
graphics graphics/nxterm: consume SGR escape sequences 2026-08-23 10:46:02 +08:00
include ioexpander/ch422g: add a driver for the WCH CH422G I/O 2026-08-24 09:39:58 +02:00
libs arch/tricore: drop illd dependence for atomic 2026-08-25 10:07:25 +08:00
mm cmake: Use NUTTX(_DIR/_BIN_DIR) instead CMAKE(_SRC_DIR/_BIN_DIR) 2026-08-09 11:13:08 -03:00
net net/local: fix SCM_RIGHTS pointer and memory corruption 2026-08-21 02:19:10 +08:00
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 nuttx/atomic: replace atomic_fetch_xxx with atomic_xxx just like zephyr 2026-08-24 13:20:45 +08:00
syscall sched: add supplementary group IDs (setgroups/getgroups/initgroups) 2026-08-12 16:06:03 -03:00
tools tools/nxstyle: require a blank line after a function's declarations 2026-08-25 19:20:08 +08:00
video tools: fix stale archive members surviving a Kconfig-driven CSRCS change 2026-07-28 21:26:03 -03:00
wireless nuttx/atomic: replace atomic_fetch_xxx with atomic_xxx just like zephyr 2026-08-24 13:20:45 +08:00
.asf.yaml github: master branch protection tune. 2025-05-07 18:37:13 -05:00
.codespell-ignore-lines arch/arm: Reserve r10 via ARCHCFLAGS and hoist the PIC module flags. 2026-07-24 23:09:08 +08:00
.codespellrc arch/arm/rp23xx: Add hardware TRNG driver for /dev/random. 2026-07-25 15:06:56 +08:00
.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
.pre-commit-config.yaml pre-commit: enable codespell checks 2025-05-05 12:34:39 +08:00
.yamllint feat: add a GitHub action to lint the YAML files 2020-12-15 09:52:04 -06:00
AUTHORS AUTHORS: add Jorge Guzman 2026-08-25 08:43:13 -04:00
CMakeLists.txt Revert "cmake: normalize .config on reconfigure" 2026-08-13 07:54:00 +02:00
CONTRIBUTING.md contributing: Add requirement for 'Assisted-by' commit field 2026-07-12 09:42:28 +08:00
INVIOLABLES.md INVIOLABLES.md: Fix a simple alignment and change occurrences of Nuttx 2020-09-03 01:33:05 +08:00
Kconfig drivers/clk: Add debug output levels. 2026-08-16 23:23:04 +08:00
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 Remove the double blank line from source files 2022-02-20 20:10:14 +01:00
README.md ci/testing: Add MemBrowse Integration 2026-06-18 12:07:41 -03:00
ReleaseNotes Documentation: move ReleaseNotes 2023-09-26 20:41:00 +08:00

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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.