Copyright (c) 2012 Bjoern A. Zeeb <bz@FreeBSD.org>
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$FreeBSD: releng/10.2/share/man/man4/wbwd.4 244796 2012-12-28 23:21:54Z delphij $
.Dd December 28, 2012 .Dt WBWD 4 .Os .Sh NAME .Nm wbwd .Nd device driver for watchdog timer found on Winbond Super I/O chips .Sh SYNOPSIS To compile this driver into the kernel, place the following line in your kernel configuration file: d -ragged -offset indent .Cd "device wbwd" .Ed
p Alternatively, to load the driver as a module at boot time, place the following line in .Xr loader.conf 5 : d -literal -offset indent wbwd_load="YES" .Ed .Sh DESCRIPTION The .Nm driver provides .Xr watchdog 4 support for the watchdog interrupt timer present on at least the following Winbond Super I/O chips:
p l -bullet -compact t 83627HF/F/HG/G Rev. G t 83627HF/F/HG/G Rev. J t 83627HF/F/HG/G Rev. UD-A t 83627DHG IC ver. 5 .El .Sh SYSCTL VARIABLES The .Nm driver provides the following options as .Xr sysctl 8 variables. l -tag -width "xxxxxx" t Va dev.wbwd.0.timeout_override This variable allows to program the timer to a value independent on the one provided by the .Xr watchdog 4 framework while still relying on the regular updates from e.g. .Xr watchdogd 8 . This is particularly useful if your system provides multiple watchdogs and you want them to fire in a special sequence to trigger an NMI after a shorter period than the reset timeout for example. The value set must not be lower than the sleep time of .Xr watchdogd 8 . A value of 0 disables this feature and the timeout value provided by .Xr watchdog 4 will be used. t Va dev.wbwd.0.debug_verbose If set this sysctl will tell the driver to log its current state before and after the timer reset on each invocation from .Xr watchdog 9 to the kernel message buffer for debugging. t Va dev.wbwd.0.debug This read-only value gives the state of some registers on last update. .El
p The .Nm driver also provides further sysctl options that are hidden by default. See the source code for more information. .Sh SEE ALSO .Xr watchdog 4 , .Xr device.hints 5 , .Xr watchdog 8 , .Xr watchdogd 8 , .Xr watchdog 9 .Sh HISTORY The .Nm driver first appeared in .Fx 10.0 . .Sh AUTHORS .An -nosplit This manual page was written by .An Bjoern A. Zeeb Aq bz@FreeBSD.org .