FreeBSD manual
download PDF document: ichwd.4.pdf
ICHWD(4) FreeBSD Kernel Interfaces Manual ICHWD(4)
NAME
ichwd - device driver for the Intel ICH watchdog interrupt timer
SYNOPSIS
To compile this driver into the kernel, place the following line in your
kernel configuration file:
device ichwd
Alternatively, to load the driver as a module at boot time, place the
following line in loader.conf(5):
ichwd_load="YES"
DESCRIPTION
The ichwd driver provides watchdog(4) support for the watchdog interrupt
timer present on all Intel ICH motherboard chipsets.
The ICH WDT counts down in ticks of approximately 0.6 seconds; the exact
value depends on hardware quality and environmental factors. Supported
watchdog intervals range from 2 to 63 ticks.
Note that on some ICH-based systems, the WDT may be present but disabled,
either in hardware or by the BIOS. The ichwd driver attempts to detect
this condition and will refuse to attach if it believes the WDT is
disabled.
SEE ALSO
watchdog(4), watchdog(8), watchdogd(8), watchdog(9)
Using the Intel ICH Family Watchdog Timer (WDT), Intel Application Note
AP-725, Document Number 292273-001.
HISTORY
The ichwd driver first appeared in FreeBSD 5.3.
AUTHORS
The ichwd driver was written by Wm. Daryl Hawkins <dhawkins@tamu.edu> of
Texas A&M University and Dag-Erling Smorgrav <des@FreeBSD.org>. This
manual page was written by Dag-Erling Smorgrav <des@FreeBSD.org>.
FreeBSD 14.0-RELEASE-p11 August 20, 2008 FreeBSD 14.0-RELEASE-p11