1.\" 2.\" Copyright (c) 2015 John Baldwin <jhb@FreeBSD.org> 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 13.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 14.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 16.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 17.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 18.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 19.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 20.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 21.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 22.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 23.\" SUCH DAMAGE. 24.\" 25.\" $FreeBSD$ 26.\" 27.Dd June 1, 2021 28.Dt DEVCTL 8 29.Os 30.Sh NAME 31.Nm devctl 32.Nd device control utility 33.Sh SYNOPSIS 34.Nm 35.Cm attach 36.Ar device 37.Nm 38.Cm clear driver 39.Op Fl f 40.Ar device 41.Nm 42.Cm detach 43.Op Fl f 44.Ar device 45.Nm 46.Cm disable 47.Op Fl f 48.Ar device 49.Nm 50.Cm enable 51.Ar device 52.Nm 53.Cm suspend 54.Ar device 55.Nm 56.Cm resume 57.Ar device 58.Nm 59.Cm set driver 60.Op Fl f 61.Ar device driver 62.Nm 63.Cm rescan 64.Ar device 65.Nm 66.Cm delete 67.Op Fl f 68.Ar device 69.Nm 70.Cm freeze 71.Nm 72.Cm thaw 73.Nm 74.Cm reset 75.Op Fl d 76.Ar device 77.Sh DESCRIPTION 78The 79.Nm 80utility adjusts the state of individual devices in the kernel's 81internal device hierarchy. 82Each invocation of 83.Nm 84consists of a single command followed by command-specific arguments. 85Each command operates on a single device specified via the 86.Ar device 87argument. 88The 89.Ar device 90may be specified either as the name of an existing device or as a 91bus-specific address. 92More details on supported address formats can be found in 93.Xr devctl 3 . 94.Pp 95The following commands are supported: 96.Bl -tag -width indent 97.It Cm attach Ar device 98Force the kernel to re-probe the device. 99If a suitable driver is found, 100it is attached to the device. 101.It Xo Cm detach 102.Op Fl f 103.Ar device 104.Xc 105Detach the device from its current device driver. 106If the 107.Fl f 108flag is specified, 109the device driver will be detached even if the device is busy. 110.It Xo Cm disable 111.Op Fl f 112.Ar device 113.Xc 114Disable a device. 115If the device is currently attached to a device driver, 116the device driver will be detached from the device, 117but the device will retain its current name. 118If the 119.Fl f 120flag is specified, 121the device driver will be detached even if the device is busy. 122.It Cm enable Ar device 123Enable a device. 124The device will probe and attach if a suitable device driver is found. 125Note that this can re-enable a device disabled at boot time via a 126loader tunable. 127.It Cm suspend Ar device 128Suspend a device. 129This may include placing the device in a reduced power state. 130.It Cm resume Ar device 131Resume a suspended device to a fully working state. 132.It Xo Cm set driver 133.Op Fl f 134.Ar device driver 135.Xc 136Force the device to use a device driver named 137.Ar driver . 138If the device is already attached to a device driver and the 139.Fl f 140flag is specified, 141the device will be detached from its current device driver before it is 142attached to the new device driver. 143If the device is already attached to a device driver and the 144.Fl f 145flag is not specified, 146the device will not be changed. 147.It Xo Cm clear driver 148.Op Fl f 149.Ar device 150.Xc 151Clear a previously-forced driver name so that the device is able to use any 152valid device driver. 153After the previous name has been cleared, 154the device is reprobed so that other device drivers may attach to it. 155This can be used to undo an earlier 156.Cm set driver 157command. 158If the device is currently attached to a device driver and the 159.Fl f 160flag is not specified, 161the device will not be changed. 162.It Cm rescan Ar device 163Rescan a bus device checking for devices that have been added or 164removed. 165.It Xo Cm delete 166.Op Fl f 167.Ar device 168.Xc 169Delete the device from the device tree. 170If the 171.Fl f 172flag is specified, 173the device will be deleted even if it is physically present. 174This command should be used with care as a device that is deleted but present 175can no longer be used unless the parent bus device rediscovers the device via 176a rescan request. 177.It Cm freeze 178Freeze probe and attach processing initiated in response to drivers being 179loaded. 180Drivers are placed on a 181.Do 182frozen list 183.Dc 184and processed when a later 185.Do 186thaw 187.Dc 188occurs. 189.It Cm thaw 190Resume (thaw the freeze) probe and attach initiated in response to drivers 191being loaded. 192In addition to resuming, all pending actions that were frozen during the freeze 193are performed. 194.It Xo Cm reset 195.Op Fl d 196.Ar device 197.Xc 198Reset the device, using bus-specific reset method. 199Drivers for the devices being reset are suspended around the reset. 200If the 201.Fl d 202option is specified, drivers are detached instead. 203.Pp 204Currently, resets are implemented for PCIe buses and PCI devices. 205For PCIe bus, the link is disabled and then re-trained, causing all 206children of the bus to reset. 207Use 208.Fl p 209option of 210.Xr devinfo 8 211tool to report parent bus for the device. 212For PCI device, if Function-Level Reset is implemented by it, FLR is 213tried first; if failed or not implemented, power reset is tried. 214.Pp 215If you have detached or suspended a child device explicitly and then 216do a reset, the child device will end up attached. 217.El 218.Sh SEE ALSO 219.Xr devctl 3 , 220.Xr devinfo 8 221.Sh HISTORY 222The 223.Nm 224utility first appeared in 225.Fx 10.3 . 226.Sh BUGS 227Currently there is no administrative flag to prevent re-attach or resume 228of the manually detached or suspended devices after reset. 229Similarly, there is no flag to prevent un-suspending of the the manually 230suspended devices after system resume. 231