1260: time/ticker: make sure the future for .next() is Unpin. r=Dirbaio a=Dirbaio
It was Unpin before #1248
bors r+
Co-authored-by: Dario Nieuwenhuis <dirbaio@dirbaio.net>
> dirbaio: so I was checking how zephyr does UARTE RX on nRF
> dirbaio: because currently we have the ugly "restart DMA on line idle to flush it" hack
> dirbaio: because according to the docs "For each byte received over the RXD line, an RXDRDY event will be generated. This event is likely to occur before the corresponding data has been transferred to Data RAM."
> dirbaio: so as I understood it, the only way to guarantee the data is actually transferred to RAM is to stop+restart DMA
> dirbaio: well, guess what?
> dirbaio: they just count RXDRDY's, and process that amount of data without restarting DMA
> dirbaio: with a timer configured as counter https://github.com/zephyrproject-rtos/zephyr/blob/main/drivers/serial/uart_nrfx_uarte.c#L650-L692
> dirbaio: 🤔🤷⁉️
> dirbaio: someone saying you can do the "hook up rxdrdy to a counter" trick, someone else saying it's wrong 🤪https://devzone.nordicsemi.com/f/nordic-q-a/28420/uarte-in-circular-mode
So we're going to do just that!
- BufferedUarte is lock-free now. No PeripheralMutex.
- The "restart DMA on line idle to flush it" hack is GONE. This means
- It'll work correctly without RTS/CTS now.
- It'll have better throughput when using RTS/CTS.
When using gpio pin changes for things like peripheral interrupts these
debug! calls flood defmt, making it difficult to find what you're
actually looking for.
1255: common: allow atomic ringbuf to fill up to N instead of just N-1. r=Dirbaio a=Dirbaio
Extracted out of #1208. Since I don't think that'll end up using the ringbuf in the end, I've separated it.
This allows the ringbuf to be filled up to `N` instead of just `N-1`, using some fun tricks on the indices.
The advantage is better performance: Before, the first write would fill N-1 bytes, The second would write just the 1 byte left before wrapping, then N-2. Then 2, then N-3, and so on. This would result in more smaller chunks, so worse perf. This problem is gone now.
bors r+
Co-authored-by: Dario Nieuwenhuis <dirbaio@dirbaio.net>
This allows the ringbuf to be filled up to `N` instead of just `N-1`, using some fun tricks on the indices.
The advantage is better performance: Before, the first write would fill N-1 bytes, The second would write just the 1 byte left before wrapping, then N-2. Then 2, then N-3, and so on. This would result in more smaller chunks, so worse perf. This problem is gone now.
