aeaf718fc9
The RP2350 has two system timer blocks (TIMER0, TIMER1), each a free-running 64-bit counter incremented once per microsecond by the TICKS block (set up in rp23xx_clock.c). They are independent of the ARM SysTick that drives the OS tick, so they are free for application use, but the port had no driver for them. Add rp23xx_timer.c, a NuttX timer lower-half that binds a block to a /dev/timerN device. It uses ALARM0 of the block, which matches the low 32 bits of the microsecond counter, to implement single-shot and periodic timeouts with 1 us resolution and a maximum interval of 2^32 - 1 us (~71.5 minutes). Periodic reloads are scheduled relative to the previous expiry to avoid drift, but never behind the counter (an alarm set in the past would not match until the 32-bit counter wraps). Enable with CONFIG_RP23XX_TIMER (which selects CONFIG_TIMER), then turn on each block independently: CONFIG_RP23XX_TIMER0 registers /dev/timer0 and CONFIG_RP23XX_TIMER1 registers /dev/timer1. A block claimed by the tickless oneshot (CONFIG_RP23XX_SYSTIMER_TICKLESS) is excluded from these choices in Kconfig, so the two features can be enabled together without colliding on the same block or its alarm IRQ. Tested on Pimoroni Pico Plus 2 (RP2350B) hardware with examples/timer and a CMSIS-DAP probe. The device registers as /dev/timer0; the ALARM0 interrupt fires at the programmed period (verified over SWD at the configured 1 s interval, not a busy loop), and the full path -- alarm match, the driver ISR, the timer notification and delivery of the SIGNO to user space -- reaches the example's signal handler and increments its counter. Assisted-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com> Signed-off-by: Marco Casaroli <marco.casaroli@gmail.com> |
||
|---|---|---|
| .github | ||
| arch | ||
| audio | ||
| binfmt | ||
| boards | ||
| cmake | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| dummy | ||
| fs | ||
| graphics | ||
| include | ||
| libs | ||
| mm | ||
| net | ||
| openamp | ||
| pass1 | ||
| sched | ||
| syscall | ||
| tools | ||
| video | ||
| wireless | ||
| .asf.yaml | ||
| .codespell-ignore-lines | ||
| .codespellrc | ||
| .editorconfig | ||
| .gitignore | ||
| .gitmessage | ||
| .pre-commit-config.yaml | ||
| .yamllint | ||
| AUTHORS | ||
| CMakeLists.txt | ||
| CONTRIBUTING.md | ||
| INVIOLABLES.md | ||
| Kconfig | ||
| LICENSE | ||
| Makefile | ||
| NOTICE | ||
| README.md | ||
| ReleaseNotes | ||
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.