drivers: serial: nrfx_uarte: Add support for higher baudrates #84485
Conversation
Add faster baudrates (2M, 4M and 8M). Signed-off-by: Krzysztof Chruściński <[email protected]>
nordic-krch
requested review from
gmarull,
anangl,
masz-nordic,
kl-cruz and
nika-nordic
| @@ -43,3 +43,6 @@ properties: | |||
| - 460800 | |||
| - 921600 | |||
| - 1000000 | |||
| - 2000000 | |||
There was a problem hiding this comment.
shouldn't we introduce nordic,nrf-uart-fast.yaml or similar to differentiate between devices that have >1Mbaud capabilities? Take a look at this PR for reference: #79330
There was a problem hiding this comment.
Driver compilation will fail if not supported current-speed is set for an instance. Alternative approach would be to use separate compatible but this will trigger more work as currently current-speed is an enum in nordic,nrf-uart-common.yaml and that would need to be extracted because enums in bindings cannot be overwritten. Additionally, support for two compatibles would need be added in places like:
zephyr/drivers/pinctrl/pinctrl_nrf.c
Line 45 in c3f979b
There was a problem hiding this comment.
If we where completely true to the devicetree, if its the "same" underlying hardware block, and "fast" just means, "supports higher bitrate", we would add a flag/boolean to the common binding like:
uart@xxx {
compatible = "nordic,nrf-uarte"; /* same hardware, targets same driver */
fast; /* <this instance is fast */
};
the current-speed enum should contain a superset of all supported speeds, for all variations, including fast, the driver then validates current-speed based on if the fast; flag exists. DT really is not there to validate stuff like current-speed, current-speed is a zephyr-ism we use to set initial configs, DT enums are just a "base filter"
There was a problem hiding this comment.
Consider how many nordic,nrf-comp variations there would be if we had one compat if it supported low power mode, one if it supported some specific subset of voltage references etc. pure chaos :)
Rename UARTE_ANY_FAST to UARTE_ANY_FAST_PD. There are 2 types of 'fast' UARTE instances. In nrf54h20 instance uart120 is in fast power domain that requires additional power and clock management of that domain. In nrf54lx fast uart00 instance does not require that. Add _PD to indicate fast power domain. Signed-off-by: Krzysztof Chruściński <[email protected]>
nrf54x devices have UARTE instance capable of using baudrate higher than 1M. Higher baudrates does not have predefined values for BAUDRATE register. A formula can be used to calculate BAUDRATE value that shall be used for desired baudrate. Add UARTE_ANY_HIGH_SPEED macro which is set when high speed is enabled (uart00 in nrf54lx or uart120 in nrf54h20). For high speed instance use formula for getting value that shall be written to BAUDRATE register. When runtime configuration is not used then same formula is used to calculate fixed BAUDRATE value. Signed-off-by: Krzysztof Chruściński <[email protected]>
nordic-krch
force-pushed
the
nrfx_uarte_4m
branch
from
907bab6 to
c3f979b
Compare
Fast instance in nrf54h (uart120) can generate a spurious RXTO event some time after RXTO event that indicates that RX path is disabled. The time when event is generated depends on baudrate and when slower baudrates are used peripheral is disabled on time to not notice it in the test but with higher baudates issue become visible. In order to avoid spurious interrupt, RXTO interrupt is disabled during RXTO event handling and enabled when RX is enabled. This workaround is applied only for fast instance to avoid unnecessary register accesses for slower instances. Signed-off-by: Krzysztof Chruściński <[email protected]>
Test was staring a TX transfer and aborting it after 300 us from the timer handler. Test was assuming that ongoing transfer will not finish in those 300 us. This might not be true for higher baudrates. Instead of using fixed timeout, a value is calculated from the baudrate and targets to abort the transfer after approx. 20 bytes of 95 byte long transfer. Signed-off-by: Krzysztof Chruściński <[email protected]>
Use high baudrate when testing uart120 on nrf54h20dk/nrf54h20/cpuapp. Signed-off-by: Krzysztof Chruściński <[email protected]>
Fast instances (uart00 in nRF54Lx and uart120 in nRF54H20) support >1M baudates. Extend driver to support that.
Updated overlay for nrf54h20dk in
uart_async_apitest to use 4Mbaud for uart120 instance. This shown an issue in the test which was not ready for higher baudrates. Test was tweaked to adjust its timings based on used baudrate.