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 October 31, 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.Nm 78.Cm getpath 79.Ar locator 80.Ar device 81.Sh DESCRIPTION 82The 83.Nm 84utility adjusts the state of individual devices in the kernel's 85internal device hierarchy. 86Each invocation of 87.Nm 88consists of a single command followed by command-specific arguments. 89Each command operates on a single device specified via the 90.Ar device 91argument. 92The 93.Ar device 94may be specified either as the name of an existing device or as a 95bus-specific address. 96More details on supported address formats can be found in 97.Xr devctl 3 . 98.Pp 99The following commands are supported: 100.Bl -tag -width indent 101.It Cm attach Ar device 102Force the kernel to re-probe the device. 103If a suitable driver is found, 104it is attached to the device. 105.It Xo Cm detach 106.Op Fl f 107.Ar device 108.Xc 109Detach the device from its current device driver. 110If the 111.Fl f 112flag is specified, 113the device driver will be detached even if the device is busy. 114.It Xo Cm disable 115.Op Fl f 116.Ar device 117.Xc 118Disable a device. 119If the device is currently attached to a device driver, 120the device driver will be detached from the device, 121but the device will retain its current name. 122If the 123.Fl f 124flag is specified, 125the device driver will be detached even if the device is busy. 126.It Cm enable Ar device 127Enable a device. 128The device will probe and attach if a suitable device driver is found. 129Note that this can re-enable a device disabled at boot time via a 130loader tunable. 131.It Cm suspend Ar device 132Suspend a device. 133This may include placing the device in a reduced power state. 134.It Cm resume Ar device 135Resume a suspended device to a fully working state. 136.It Xo Cm set driver 137.Op Fl f 138.Ar device driver 139.Xc 140Force the device to use a device driver named 141.Ar driver . 142If the device is already attached to a device driver and the 143.Fl f 144flag is specified, 145the device will be detached from its current device driver before it is 146attached to the new device driver. 147If the device is already attached to a device driver and the 148.Fl f 149flag is not specified, 150the device will not be changed. 151.It Xo Cm clear driver 152.Op Fl f 153.Ar device 154.Xc 155Clear a previously-forced driver name so that the device is able to use any 156valid device driver. 157After the previous name has been cleared, 158the device is reprobed so that other device drivers may attach to it. 159This can be used to undo an earlier 160.Cm set driver 161command. 162If the device is currently attached to a device driver and the 163.Fl f 164flag is not specified, 165the device will not be changed. 166.It Cm rescan Ar device 167Rescan a bus device checking for devices that have been added or 168removed. 169.It Xo Cm delete 170.Op Fl f 171.Ar device 172.Xc 173Delete the device from the device tree. 174If the 175.Fl f 176flag is specified, 177the device will be deleted even if it is physically present. 178This command should be used with care as a device that is deleted but present 179can no longer be used unless the parent bus device rediscovers the device via 180a rescan request. 181.It Cm freeze 182Freeze probe and attach processing initiated in response to drivers being 183loaded. 184Drivers are placed on a 185.Do 186frozen list 187.Dc 188and processed when a later 189.Do 190thaw 191.Dc 192occurs. 193.It Cm thaw 194Resume (thaw the freeze) probe and attach initiated in response to drivers 195being loaded. 196In addition to resuming, all pending actions that were frozen during the freeze 197are performed. 198.It Xo Cm reset 199.Op Fl d 200.Ar device 201.Xc 202Reset the device, using bus-specific reset method. 203Drivers for the devices being reset are suspended around the reset. 204If the 205.Fl d 206option is specified, drivers are detached instead. 207.Pp 208Currently, resets are implemented for PCIe buses and PCI devices. 209For PCIe bus, the link is disabled and then re-trained, causing all 210children of the bus to reset. 211Use 212.Fl p 213option of 214.Xr devinfo 8 215tool to report parent bus for the device. 216For PCI device, if Function-Level Reset is implemented by it, FLR is 217tried first; if failed or not implemented, power reset is tried. 218.Pp 219If you have detached or suspended a child device explicitly and then 220do a reset, the child device will end up attached. 221.It Xo Cm getpath 222.Ar locator 223.Ar device 224.Xc 225Prints the full path to the 226.Ar device 227using the 228.Ar locator 229method to get the path name. 230Currently, only the 231.Dq UEFI 232and 233.Dq FreeBSD 234locators are implemented. 235The UEFI locator constructs a path to the device using the rules 236outlines for DEVICE_PATH in the UEFI standard. 237The FreeBSD locator constructs a path back to the root of the tree 238with the nodes separated by slashes. 239.El 240.Sh SEE ALSO 241.Xr devctl 3 , 242.Xr devinfo 8 243.Sh HISTORY 244The 245.Nm 246utility first appeared in 247.Fx 10.3 . 248.Sh BUGS 249Currently there is no administrative flag to prevent re-attach or resume 250of the manually detached or suspended devices after reset. 251Similarly, there is no flag to prevent un-suspending of the manually 252suspended devices after system resume. 253