cpu/stm32_common/uart: fix rare uart failure #12100
Merged
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
added 2 commits
August 27, 2019 19:09
in uart_poweroff the peripheral should be disabled through the register instead of just disabling the peripheral clock. In uart_poweron the peripheral should be enabled after enabling the clock. Not explicitely disabling the peripheral causes some bad signals on the uart line sometimes.
once hardware flow control is enabled, rts should only be initialized after the uart is enabled by setting the UE flag. This is stated in the stm32f4 errata.
aabadie
added
Area: cpu
aabadie
added
CI: ready for build
aabadie
reviewed
Sep 9, 2019
There was a problem hiding this comment.
LGTM. @fjmolinas is it possible to test this PR on your STM32 cluster ?
Will do, I'm testing some watchdog stuff but I will do that promptly. Do you want to run all tests or a subset? |
This is touching UART so I don't see any particular restriction. Just run them all :) |
|
Here are the results: failuresummary.mdnucleo-f091rc/failuresummary.mdThe failures with @toonst if possible could you post the terminal output that showed the issue. |
aabadie
approved these changes
Sep 10, 2019
There was a problem hiding this comment.
No obvious failure reported by @fjmolinas. We discussed the problem IRL with @toonst and the changes of this PR make sense.
Let's merge this, so ACK.
If there is more context to what is stated in the PR, its better if you also comment it in the PR.
For future PR's it would be ideal if you could post in the PR the details of your setup that caused the issue and some terminal output that showcases it. In any case thanks for the fix! |
|
I used our custom app & board to reproduce this issue. I will try to find time to make an upstreamable test to reproduce. |
No need in this case, its unnecessary overhead here. My comment was just intended as a suggestion for future PR's ;) . |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Contribution description
in
uart_poweroffthe peripheral should be disabled through the register instead of just disabling the peripheral clock. Inuart_poweronthe peripheral should be enabled after enabling the clock.This change seems to fix some rare issues with the uart not working properly after a power off.
Testing procedure
I reproduced the issue by letting a custom app run for a few hours which powers the uart on & off. At some point the uart_write was not actually sending any data on the TX line.
Issues/PRs references
none