ot_flash: Re-enable disabled flash MMIO region on reset
#210
Conversation
This file contains hidden or 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
This helps debugging races involving flash resets, so it is quite useful to have as a trace. Signed-off-by: Alex Jones <alex.jones@lowrisc.org>
Although the `DIS` disablement register was being reset on reset, the flash mmio `mem` memory region's enablement was not being reset. This caused some difficult to debug issues due to QEMU's non-determinism where resets could occur before or after SW disables the flash, essentially permanently locking Earlgrey out of its flash. Signed-off-by: Alex Jones <alex.jones@lowrisc.org>
jwnrt
approved these changes
Oct 3, 2025
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
3 participants
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Outdated suggestions cannot be applied.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.
Although the
DISdisablement register was being reset on reset, the flashmmio.memmemory region's enablement was not being reset. This caused some difficult to debug issues due to QEMU's non-determinism where resets could occur before or after SW disables the flash on ROM_EXT boot failures, essentially permanently locking Earlgrey out of its flash in some executions. Fix this and add a trace to make future debugging easier.