src/sys/time/timekeeper/config.shard.cml

// Copyright 2022 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
{
    config: {
        // The primary time source URL represents a component to be installed to receive time
        // updates. There is no maximum URL length defined by RFC 3986, but this length should
        // be long enough to accommodate most non-data: URLs.
        // See https://fxbug.dev/42130991 for additional context on this value.
        primary_time_source_url: {
            type: "string",
            max_size: 4096,
        },

        // If set, causes the monitor time source to start this component as a
        // monitor mode time source.
        monitor_time_source_url: {
            type: "string",
            max_size: 4096,
        },

        // The standard deviation of the system oscillator frequency error in parts per million,
        // used to control the growth in error bound and bound the allowed frequency estimates.
        oscillator_error_std_dev_ppm: { type: "uint32" },

        // The maximum allowed frequency error in parts per million away from the nominal 1ns
        // UTC == 1ns monotonic.
        max_frequency_error_ppm: { type: "uint32" },

        // Flag for disabling delays, allowing a test to push samples frequently.
        disable_delays: { type: "bool" },

        // Initial frequency in parts per million, at which UTC time moves with respect to
        // monotonic time on the device. Value greater than 1*10^6 means that the device oscillator
        // is slower than the real time.
        initial_frequency_ppm: { type: "uint32" },

        // Flag for enabling usage of `PullSource` API for the monitor track.
        // If set to false, monitor track is not used.
        monitor_uses_pull: { type: "bool" },

        // The time to wait until retrying to sample the pull
        // time source, expressed in seconds.
        back_off_time_between_pull_samples_sec: { type: "int64" },

        // The time to wait before sampling the time source for the first time,
        // expressed in seconds.
        first_sampling_delay_sec: { type: "int64" },

        // Flag for enabling usage of `PullSource` API for the primary track.
        // If set to false, `PullSource` is not used.
        primary_uses_pull: { type: "bool" },

        // If set, the UTC clock is started at timekeeper startup, even if
        // no reliable UTC estimate is available.
        //
        // This helps buggy programs which assume UTC clock is monotonic, and
        // use it to measure time durations.
        utc_start_at_startup: { type: "bool" },

        // If set, timekeeper will exit early without managing the clock.
        early_exit: { type: "bool" },

        // If set, timekeeper will attempt to contact the System Activity
        // Governor, and/or Power Broker to take part in the system's power
        // topology.
        power_topology_integration_enabled: { type: "bool" },

        // If set, Timekeeper will only read the RTC, never update it.
        rtc_is_read_only: { type: "bool" },
    },
}