Implement ACPI time-alarm device

[williampMSFT]

This change implements an ACPI time-and-alarm device as defined in section 9.18 of the ACPI 6.4 spec.

Such a device needs to interface with the not-yet-existent power service to trigger wakes and subscribe to power source notifications, so those interface points are stubbed out for now.

Resolves #138, #139, #140, #141, #142, #143, #144

[williampMSFT]

Replaces #501, which was targeting the main branch (this now depends on the comms rework that's currently only available in v0.2.0).

[github-actions]

Cargo Vet Audit Passed

cargo vet has passed in this PR. No new unvetted dependencies were found.

[Copilot]

Pull request overview

This PR implements an ACPI time-and-alarm device as defined in section 9.18 of the ACPI 6.4 specification. The implementation includes a new service for managing AC and DC power timers with wake capabilities, timer status tracking, and timezone/DST management. Power service integration points are stubbed for future implementation.

Changes:

• Adds time-alarm-service crate with timer logic, persistent storage, and ACPI command handling
• Adds time-alarm-service-messages crate with message serialization/deserialization for ACPI time/alarm operations
• Integrates the service into the eSPI MCTP relay system
• Removes legacy TimeAlarm structures from EC memory map in favor of the new service-based approach
• Updates dependency versions (num_enum 0.7.4 → 0.7.5, PAC updates, embassy-imxrt updates)

Reviewed changes

Copilot reviewed 15 out of 21 changed files in this pull request and generated 6 comments.

Show a summary per file

File	Description
time-alarm-service/src/lib.rs	Main service implementation with ACPI command handling and power source management
time-alarm-service/src/timer.rs	Timer state machine with wake policy handling and expiration logic
time-alarm-service/src/task.rs	Async task definitions for command handling and timer tasks
time-alarm-service-messages/src/lib.rs	ACPI message types and serialization/deserialization
time-alarm-service-messages/src/acpi_timestamp.rs	ACPI timestamp structure with timezone and DST support
time-alarm-service/Cargo.toml	Service dependencies and feature configuration
time-alarm-service-messages/Cargo.toml	Message library dependencies
espi-service/src/mctp.rs	Integration of TimeAlarm service into MCTP relay
espi-service/Cargo.toml	Added time-alarm-service-messages dependency
embedded-service/src/relay/mod.rs	Explicit trait qualification to avoid ambiguity
embedded-service/src/ec_type/structure.rs	Removed legacy TimeAlarm structure
embedded-service/src/ec_type/mod.rs	Removed legacy time alarm memory map functions
embedded-service/src/ec_type/generator/ec_memory_map.yaml	Removed TimeAlarm from memory map definition
examples/rt685s-evk/src/bin/time_alarm.rs	Example demonstrating service usage with mock eSPI
examples/rt685s-evk/Cargo.toml	Added time-alarm service dependencies
Cargo.toml	Added time-alarm service workspace members and updated num_enum version
Cargo.lock, examples/*/Cargo.lock	Dependency lock file updates

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[Copilot]

Pull request overview

Copilot reviewed 16 out of 22 changed files in this pull request and generated 3 comments.

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Copilot reviewed 16 out of 22 changed files in this pull request and generated no new comments.

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[Copilot]

Pull request overview

Copilot reviewed 16 out of 22 changed files in this pull request and generated 3 comments.

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[Copilot]

Pull request overview

Copilot reviewed 16 out of 22 changed files in this pull request and generated 1 comment.

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[kurtjd]

Looks good. The mctp.rs file could use the same treatment in uart-service as is done here for eSPI service, but can be a separate PR.

[Copilot]

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Copilot reviewed 18 out of 24 changed files in this pull request and generated no new comments.

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[jerrysxie]

@williampMSFT How can we do integration testing with the time-alarm service? Mocking out the underlying datetime and storage and checking that the correct fields has been set in response to ACPI commands? Using a mock timer to generate expiration and wake events?

[williampMSFT]

@williampMSFT How can we do integration testing with the time-alarm service? Mocking out the underlying datetime and storage and checking that the correct fields has been set in response to ACPI commands? Using a mock timer to generate expiration and wake events?

I have been testing with the ec-test-app + this PR (OpenDevicePartnership/ec-test-app#41), some changes to soc-embedded-controller to instantiate the TAD service (although that repo just broke due to another breaking change in the v0.2.0 branch that hasn't been uptaken yet), and some updates to the ACPI tables for my test device (in ADO, I can send you a pointer offline if you're interested). I'm hoping once we land on a widely-available reference platform, we can make that capability more publicly available. I've confirmed that I can manipulate the time by fiddling with the Windows time settings and see those reflected on the EC (and vice-versa), and I've implemented all the read operations in the EC test app. Write operations are tricker because they require a rework of how we're doing input in the ec-test-app, but I'd like to do that eventually too.

I did have a PR go in yesterday to fix the build for tests in this repo (#696), so I'll look into writing some unit tests for this module as well.

[jerrysxie]

@williampMSFT How can we do integration testing with the time-alarm service? Mocking out the underlying datetime and storage and checking that the correct fields has been set in response to ACPI commands? Using a mock timer to generate expiration and wake events?

I have been testing with the ec-test-app + this PR (OpenDevicePartnership/ec-test-app#41), some changes to soc-embedded-controller to instantiate the TAD service (although that repo just broke due to another breaking change in the v0.2.0 branch that hasn't been uptaken yet), and some updates to the ACPI tables for my test device (in ADO, I can send you a pointer offline if you're interested). I'm hoping once we land on a widely-available reference platform, we can make that capability more publicly available. I've confirmed that I can manipulate the time by fiddling with the Windows time settings and see those reflected on the EC (and vice-versa), and I've implemented all the read operations in the EC test app. Write operations are tricker because they require a rework of how we're doing input in the ec-test-app, but I'd like to do that eventually too.

I did have a PR go in yesterday to fix the build for tests in this repo (#696), so I'll look into writing some unit tests for this module as well.

@williampMSFT Not blocking, it is tough to review the correctness of this kind of application logic, so having some mock to allow this to be unit testable would be ideal. If we can stand thinking about and looking at this, that would great! 👍