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alexcekay 1446961c87 arch/arm/stm32h7: Fix SPI RX DMA returning stale DCACHE data
In sporadic cases it is possible that a SPI exchange returns stale RX data from the DCACHE.

This occurs when:
- DCACHE is enabled
- DMA is used

The impact of this can be hard to debug and vanishes when the timing even changes minimally.

This is caused by the DCACHE being invalidated before the actual DMA transaction starts which violates
the recommendations from AN4839 and also does not match the implementation of other drivers on the STM32H7/STM32F7.

Fixed by invalidating the DCACHE right before the actual read, which matches the implementation
of the STM32F7 SPI driver.

Signed-off-by: alexcekay <alexander@auterion.com>
2026-04-23 16:28:36 +02:00
.github workflows/build.yml: job MSVC fix Filename too long 2026-04-13 23:55:10 +08:00
arch arch/arm/stm32h7: Fix SPI RX DMA returning stale DCACHE data 2026-04-23 16:28:36 +02:00
audio include/debug.h: Move to include/nuttx/debug.h 2026-04-07 07:50:06 -03:00
binfmt include/debug.h: Move to include/nuttx/debug.h 2026-04-07 07:50:06 -03:00
boards boards/sim: Prefer tmpfs for /tmp in rc.sysinit. 2026-04-23 10:26:21 -03:00
cmake cmake: Moved the creation of the nxtmpdir folder to the root CMake file 2026-04-22 06:22:36 +08:00
crypto include/debug.h: Move to include/nuttx/debug.h 2026-04-07 07:50:06 -03:00
Documentation sched/docs: Align ETC ROMFS text with tmpfs-first /tmp mount. 2026-04-23 10:26:21 -03:00
drivers drivers/mtd/w25n: address review comments 2026-04-23 16:26:44 +02:00
dummy build: add initial cmake build system 2023-07-08 13:50:48 +08:00
fs fs/vfs/fs_fstat.c: fix write capability check in proxy_fstat() 2026-04-16 13:35:41 +02:00
graphics include/debug.h: Move to include/nuttx/debug.h 2026-04-07 07:50:06 -03:00
include nuttx/nx: compilation error occurs 2026-04-14 13:35:26 +08:00
libs include/debug.h: Move to include/nuttx/debug.h 2026-04-07 07:50:06 -03:00
mm include/debug.h: Move to include/nuttx/debug.h 2026-04-07 07:50:06 -03:00
net net/devif: Reorder ipv4_input packet classification. 2026-04-23 15:11:08 +08:00
openamp openamp: Fix Make style 2026-03-23 18:16:46 -04:00
pass1 Makefile: Remove make depend files by make distclean 2026-02-16 16:27:57 +01:00
sched sched/docs: Align ETC ROMFS text with tmpfs-first /tmp mount. 2026-04-23 10:26:21 -03:00
syscall Makefile: Remove make depend files by make distclean 2026-02-16 16:27:57 +01:00
tools ci/testlist/risc-v-02.dat: Added boards build with CMake 2026-04-22 06:22:36 +08:00
video include/debug.h: Move to include/nuttx/debug.h 2026-04-07 07:50:06 -03:00
wireless include/debug.h: Move to include/nuttx/debug.h 2026-04-07 07:50:06 -03:00
.asf.yaml github: master branch protection tune. 2025-05-07 18:37:13 -05:00
.codespell-ignore-lines net/icmpv6: replace net_lock with conn_lock and conn_lock_dev 2025-12-29 09:42:18 +08:00
.codespellrc codespellrc: add ist to ignorelist 2025-10-14 17:42:01 +08:00
.editorconfig .editorconfig: fix character encoding property specification 2025-11-28 19:12:13 +08:00
.gitignore tools/Unix.mk: fix Untracked files defconfig.tmp-e on macOS 2026-04-15 17:10:22 +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 Donny Jiuzhu 2026-02-25 10:17:40 +01:00
CMakeLists.txt cmake: Moved the creation of the nxtmpdir folder to the root CMake file 2026-04-22 06:22:36 +08:00
CONTRIBUTING.md docs: Fix typos, formatting, and numbering in README.md and CONTRIBUTING.md. 2026-03-23 12:05:24 +01:00
INVIOLABLES.md
Kconfig tools/stackusage.py: use toolchain binaries instead of Python libraries 2026-03-17 11:26:44 -03:00
LICENSE style: fix spelling in code comments and strings 2025-05-23 10:48:41 +08:00
Makefile tools: migrate to SPDX identifier 2024-09-10 23:11:11 +08:00
NOTICE Remove the double blank line from source files 2022-02-20 20:10:14 +01:00
README.md docs: Fix typos, formatting, and numbering in README.md and CONTRIBUTING.md. 2026-03-23 12:05:24 +01:00
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.