Apache NuttX is a mature, real-time embedded operating system (RTOS) https://nuttx.apache.org/
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Justin Hammond 82fb0d8d06 drivers/usbhost: Separate the xHCI driver from the PCI bus.
Nothing in the controller driver is PCI-specific beyond finding the
registers and the interrupt, so an SoC wiring an xHCI controller
directly could not use any of it.

usbhost_xhci.c is now the driver; usbhost_xhci_pci.c is the PCI
attachment, holding the ID table, the BAR mapping and the MSI-X vector.
include/nuttx/usb/xhci.h carries what passes between them: the register
base, a way to attach the interrupt, and a name to report the controller
by, since a system may have more than one.

The interrupt belongs to the bus: the bus attaches and detaches it, and
the driver never holds an interrupt number.

USBHOST_XHCI is the driver and is not selectable on its own;
USBHOST_XHCI_PCI selects it.  Another bus adds its own symbol beside it.

No functional change intended.

Assisted-by: Claude:claude-opus-5
Signed-off-by: Justin Hammond <justin@dynam.ac>
2026-08-18 09:35:23 -03:00
.github ci: do not trigger Build on PR description edits 2026-08-16 19:08:58 -04:00
arch arch/arm/stm32: use common SYSTICK_HCLKd8 symbol 2026-08-18 09:34:58 +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: Add support to Waveshare esp32s3-touch-lcd-7 2026-08-18 09:33:05 -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 docs/esp32s3: Add documentation to ESP32S3-Touch-LCD-7 board 2026-08-18 09:33:05 -03:00
drivers drivers/usbhost: Separate the xHCI driver from the PCI bus. 2026-08-18 09:35:23 -03:00
dummy build: add initial cmake build system 2023-07-08 13:50:48 +08:00
fs sched,fs,docs: support setuid sudo helper 2026-08-18 15:57:52 +08:00
graphics tools: fix stale archive members surviving a Kconfig-driven CSRCS change 2026-07-28 21:26:03 -03:00
include drivers/usbhost: Separate the xHCI driver from the PCI bus. 2026-08-18 09:35:23 -03:00
libs libs/libc/machine/risc-v: Compare a register at a time on equal offsets. 2026-08-17 12:24:06 +02:00
mm cmake: Use NUTTX(_DIR/_BIN_DIR) instead CMAKE(_SRC_DIR/_BIN_DIR) 2026-08-09 11:13:08 -03:00
net net/arp: do not resolve an address to another interface's MAC 2026-08-17 11:28:45 +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 sched,fs,docs: support setuid sudo helper 2026-08-18 15:57:52 +08:00
syscall sched: add supplementary group IDs (setgroups/getgroups/initgroups) 2026-08-12 16:06:03 -03:00
tools sched,fs,docs: support setuid sudo helper 2026-08-18 15:57:52 +08:00
video tools: fix stale archive members surviving a Kconfig-driven CSRCS change 2026-07-28 21:26:03 -03:00
wireless wireless/bluetooth/bt_hcicore.c: Balance conn and buffer refs in hci_acl(). 2026-08-15 11:51:19 +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 git: Specify multiple build directories in .gitignore. 2026-05-20 03:06:58 +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
AUTHORS AUTHORS: add Eren Terzioglu 2026-05-20 15:17:00 +08:00
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
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
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.