wdt: Disarm secondary watchdog on t814x#564
Merged
jannau merged 1 commit intoAsahiLinux:mainfrom May 1, 2026
Merged
Conversation
svenpeter42
approved these changes
May 1, 2026
M4 and A18 Pro and reset with iboot from macOS 26.x after 120 seconds. This is caused by secondary watchdogs living at offset 0x8000. The ADT contains for all devices since M1 4 byte sized reg entries at those offsets. This seems to be secondary watchdogs with a different MMIO layout. Setting the offset 0x8008 to 0x0 from its initial value of 0x7b seems to disable the watchdog. This watchdog doesn't seem to have a programmable count register and uses the raw count at 0x2000. The alarm value might reside at 0x8018. The value there is close to 120 seconds with a clock 2.4 MHz. Discovered-by: @MiyakoYakota Signed-off-by: Janne Grunau <j@jannau.net>
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
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
2 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Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be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.
M4 and A18 Pro and reset with iboot from macOS 26.x after 120 seconds. This is caused by secondary watchdogs living at offset 0x8000. The ADT contains for all devices since M1 4 byte sized reg entries at those offsets. This seems to be secondary watchdogs with a different MMIO layout. Setting the offset 0x8008 to 0x0 from its initial value of 0x7b seems to disable the watchdog.
This watchdog doesn't seem to have a programmable count register and uses the raw count at 0x2000. The alarm value might reside at 0x8018. The value there is close to 120 seconds with a clock 2.4 MHz.
Discovered-by: @MiyakoYakota