wdatwd(4)

wdatwd4

Device driver for the acpi wdat based watchdog interrupt timer

Usage

device wdatwd

In loader.conf(5): wdatwd_load="YES"

Overview

The wdatwd driver provides watchdog(4) support for the watchdog interrupt timer in ACPI WDAT (Watchdog Action Table).

Since WDAT itself is an abstraction for the real hardware such as ICH WDT, it must be noted that only one driver can be used at a time, either the real hardware specific driver or this driver.

Sysctl variables

The following read-only sysctl(8) variables are available:

dev.wdatwd.%d.running

The status of the watchdog timer. 0 if not running, or 1 if running.

dev.wdatwd.%d.timeout

The current value of the watchdog timeout in millisecond. This can be 0 on some systems, and the zero value means that the default timeout is used.

dev.wdatwd.%d.timeout_configurable

Whether the timeout is configurable or not. It is 0 if configurable or any positive value if not.

dev.wdatwd.%d.timeout_default

The default value of the watchdog timeout in millisecond if any.

Releases

9 releases since FreeBSD 14.0-RELEASE; the text changed 1 time.

  1. 14.0–15.1
  2. 16.0

Authors

The wdatwd driver was written by Tetsuya Uemura ⟨[email protected]⟩ of MACOME, Corporation.

From base 16.0-CURRENT-20261027-61c70dc16a79 in FreeBSD 16.0-CURRENT (2026-10-27). Parsed by carta from the page's mdoc source.