1.\"- 2.\" Copyright (c) 2012 Bjoern A. Zeeb <bz@FreeBSD.org> 3.\" All rights reserved. 4.\" 5.\" Redistribution and use in source and binary forms, with or without 6.\" modification, are permitted provided that the following conditions 7.\" are met: 8.\" 1. Redistributions of source code must retain the above copyright 9.\" notice, this list of conditions and the following disclaimer. 10.\" 2. Redistributions in binary form must reproduce the above copyright 11.\" notice, this list of conditions and the following disclaimer in the 12.\" documentation and/or other materials provided with the distribution. 13.\" 14.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24.\" SUCH DAMAGE. 25.\" 26.\" $FreeBSD$ 27.\" 28.Dd March 24, 2016 29.Dt WBWD 4 30.Os 31.Sh NAME 32.Nm wbwd 33.Nd device driver for Winbond/Nuvoton Super I/O chips watchdog timer 34.Sh SYNOPSIS 35To compile this driver into the kernel, place the following line in your 36kernel configuration file: 37.Bd -ragged -offset indent 38.Cd "device wbwd" 39.Ed 40.Pp 41Alternatively, to load the driver as a module at boot time, place the following 42line in 43.Xr loader.conf 5 : 44.Bd -literal -offset indent 45wbwd_load="YES" 46.Ed 47.Sh DESCRIPTION 48The 49.Nm 50driver provides 51.Xr watchdog 4 52support for the watchdog interrupt timer present on at least the following 53Super I/O chips: 54.Bl -bullet -compact 55.It 56Winbond 83627HF/F/HG/G 57.It 58Winbond 83627S 59.It 60Winbond 83697HF 61.It 62Winbond 83697UG 63.It 64Winbond 83637HF 65.It 66Winbond 83627THF 67.It 68Winbond 83687THF 69.It 70Winbond 83627EHF 71.It 72Winbond 83627DHG 73.It 74Winbond 83627UHG 75.It 76Winbond 83667HG 77.It 78Winbond 83627DHG-P 79.It 80Winbond 83667HG-B 81.It 82Nuvoton NCT6775 83.It 84Nuvoton NCT6776 85.It 86Nuvoton NCT6102 87.It 88Nuvoton NCT6779 89.It 90Nuvoton NCT6791 91.It 92Nuvoton NCT6792 93.El 94.Pp 95Driver may be forced to attach to unknown chips by adding to 96.Pa /boot/device.hints : 97.Cd hint.wbwd.0.at="isa" 98.Sh SYSCTL VARIABLES 99The 100.Nm 101driver provides the following options as 102.Xr sysctl 8 103variables. 104.Bl -tag -width "xxxxxx" 105.It Va dev.wbwd.0.timeout_override 106This variable allows to program the timer to a value independent on the one 107provided by the 108.Xr watchdog 4 109framework while still relying on the regular updates from e.g. 110.Xr watchdogd 8 . 111This is particularly useful if your system provides multiple watchdogs and 112you want them to fire in a special sequence to trigger an NMI after a shorter 113period than the reset timeout for example. 114The value set must not be lower than the sleep time of 115.Xr watchdogd 8 . 116A value of 0 disables this feature and the timeout value provided by 117.Xr watchdog 4 118will be used. 119.It Va dev.wbwd.0.debug_verbose 120If set this sysctl will tell the driver to log its current state before and 121after the timer reset on each invocation from 122.Xr watchdog 9 123to the kernel message buffer for debugging. 124.It Va dev.wbwd.0.debug 125This read-only value gives the state of some registers on last update. 126.El 127.Pp 128The 129.Nm 130driver also provides further sysctl options that are hidden by default. 131See the source code for more information. 132.Sh SEE ALSO 133.Xr watchdog 4 , 134.Xr device.hints 5 , 135.Xr watchdog 8 , 136.Xr watchdogd 8 , 137.Xr watchdog 9 138.Sh HISTORY 139The 140.Nm 141driver first appeared in 142.Fx 10.0 . 143.Sh AUTHORS 144.An -nosplit 145This manual page was written by 146.An Bjoern A. Zeeb Aq Mt bz@FreeBSD.org . 147