1.\" $OpenBSD: boot_config.8,v 1.31 2019/09/06 21:30:32 cheloha Exp $ 2.\" 3.\" Copyright (c) 1996 Mats O Jansson 4.\" All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 4. Neither the name of the author nor the names of its contributors 15.\" may be used to endorse or promote products derived from this software 16.\" without specific prior written permission. 17.\" 18.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND 19.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE 22.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28.\" SUCH DAMAGE. 29.\" 30.Dd $Mdocdate: September 6 2019 $ 31.Dt BOOT_CONFIG 8 32.Os 33.Sh NAME 34.Nm boot_config 35.Nd how to change kernel configuration at boot 36.Sh DESCRIPTION 37.Nm BOOT_CONFIG 38is a kernel option that makes it possible to change the configuration 39at boot time. 40The same interface is available from userland, using the 41.Fl e 42argument to 43.Xr config 8 . 44.Pp 45The boot time configuration is invoked by passing the 46.Fl c 47option, either from the firmware prompt or, 48depending on the architecture, when the bootstrap loader 49prompts for a kernel to boot: 50.Bd -literal 51>> OpenBSD/i386 BOOT 3.26 52.No "boot>" Ic boot -c 53booting hd0a:/bsd: ... 54\&... 55real mem = 1073086464 (1023MB) 56avail mem = 1043189760 (994MB) 57User Kernel Config 58UKC> 59.Ed 60.Pp 61Changes made can be saved for the next reboot, by using 62.Xr config 8 . 63.Sh COMMANDS 64.Bl -tag -width "disable devno | dev" 65.It Ic add Ar dev 66Add a device through copying another. 67.It Ic base Cm 8 | 10 | 16 68Change the base of numbers displayed and entered. 69.It Ic change Ar devno | dev 70Modify one or more devices. 71.It Ic disable Ar devno | dev 72Disable one or more devices. 73.It Ic enable Ar devno | dev 74Enable one or more devices. 75.It Ic exit 76Continue boot. 77.It Ic find Ar devno | dev 78Find one or more devices. 79.It Ic help 80Give a short summary of all commands and their arguments. 81.It Ic list 82Show all known devices, a screen at a time. 83.It Ic lines Op Ar count 84Set the number of rows per page. 85.It Ic quit 86Continue boot. 87.It Ic show Op Ar attr Op Ar val 88Show all devices for which attribute 89.Ar attr 90has the value 91.Ar val . 92.It Ic verbose 93Toggle the autoconfig verbose variable. 94.El 95.Sh EXAMPLES 96The Ethernet card is not detected at boot because the kernel configuration 97does not match the physical hardware configuration, 98e.g. wrong IRQ in OpenBSD/i386. 99The Ethernet card is supposed to use the 100.Xr ne 4 101driver. 102.Bd -literal 103.No UKC> Ic find ne 10424 ne0 at isa0 port 0x240 size 0 iomem 0xd8000 iosiz 0 irq 9 drq -1 drq2 -1 flags 0x0 10525 ne1 at isa0 port 0x300 size 0 iomem -1 iosiz 0 irq 10 drq -1 drq2 -1 flags 0x0 10626 ne* at isapnp0 port -1 size 0 iomem -1 iosiz 0 irq -1 drq -1 flags 0x0 10727 ne* at pci* dev -1 function -1 flags 0x0 10828 ne* at pcmcia* function -1 irq -1 flags 0x0 109UKC> 110.Ed 111.Pp 112ne1 seems to match the configuration except it uses IRQ 5 instead of IRQ 10. 113So the irq on ne1 should be changed via the 114.Fa change 115command. 116The device can be specified by either name or number. 117.Bd -literal 118.No UKC> Ic change ne1 11925 ne1 at isa0 port 0x300 size 0 iomem -1 iosiz 0 irq 10 drq -1 drq2 -1 flags 0x0 120.No change (y/n) \&? Ic y 121.No port [0x300] \&? 122.No size [0] \&? 123.No iomem [-1] \&? 124.No iosiz [0] \&? 125.No irq [10] \&? Ic 5 126.No drq [-1] \&? 127.No drq2 [-1] \&? 128.No flags [0] \&? 12925 ne1 changed 13025 ne1 at isa0 port 0x300 size 0 iomem -1 iosiz 0 irq 5 drq -1 drq2 -1 flags 0x0 131UKC> 132.Ed 133.Pp 134The show command is useful for finding which devices have a certain attribute. 135It can also be used to find those devices with a particular value for 136an attribute. 137.Bd -literal 138.No UKC> Ic show slot 139 2 ahc* at eisa0 slot -1 flags 0x0 140 10 uha* at eisa0 slot -1 flags 0x0 141 12 ep0 at eisa0 slot -1 flags 0x0 142 17 ep* at eisa0 slot -1 flags 0x0 143102 ahb* at eisa0 slot -1 flags 0x0 144103 fea* at eisa0 slot -1 flags 0x0 145.No UKC> Ic show port 0x300 146 25 ne1 at isa0 port 0x300 size 0 iomem -1 iosiz 0 irq 10 drq -1 drq2 -1 flags 0x0 147 72 we1 at isa0 port 0x300 size 0 iomem 0xcc000 iosiz 0 irq 10 drq -1 drq2 -1 flags 0x0 148 75 el0 at isa0 port 0x300 size 0 iomem -1 iosiz 0 irq 9 drq -1 drq2 -1 flags 0x0 149 77 ie1 at isa0 port 0x300 size 0 iomem -1 iosiz 0 irq 10 drq -1 drq2 -1 flags 0x0 150UKC> 151.Ed 152.Pp 153It is possible to add new devices, but only devices that were linked into the 154kernel. 155If a new device is added, following devices will be renumbered. 156.Bd -literal 157.No UKC> Ic find ep 158 11 ep0 at isa0 port -1 size 0 iomem -1 iosiz 0 irq -1 drq -1 drq2 -1 flags 0x0 159 12 ep0 at eisa0 slot -1 flags 0x0 160 13 ep0 at pci* dev -1 function -1 flags 0x0 161 14 ep* at isapnp0 port -1 size 0 iomem -1 iosiz 0 irq -1 drq -1 flags 0x0 162 15 ep* at isa0 port -1 size 0 iomem -1 iosiz 0 irq -1 drq -1 drq2 -1 flags 0x0 163 16 ep* at eisa0 slot -1 flags 0x0 164 17 ep* at pci* dev -1 function -1 flags 0x0 165 18 ep* at pcmcia* dev -1 irq -1 flags 0x0 166.No UKC> Ic add ep1 167.No "Clone Device (DevNo, 'q' or '\&?') \&?" Ic 13 168.No "Insert before Device (DevNo, 'q' or '\&?')" Ic 14 169 14 ep1 at pci* dev -1 function -1 170.No UKC> Ic change 14 171 14 ep1 at pci* dev -1 function -1 172.No change (y/n) \&? Ic y 173.No dev [-1] \&? Ic 14 174.No function [-1] \&? 175.No flags [0] \&? Ic 18 176 14 ep1 changed 177 14 ep1 at pci* dev 14 function -1 flags 0x12 178UKC> 179.Ed 180.Pp 181When configuration is completed, booting can proceed by issuing the 182.Ic quit 183or 184.Ic exit 185commands. 186.Bd -literal 187.No UKC> Ic quit 188Continuing... 189mainbus0 (root) 190.Ed 191.Sh SEE ALSO 192.Xr config 8 193.Sh AUTHORS 194.An Mats O Jansson Aq Mt moj@stacken.kth.se 195.Sh BUGS 196The 197.Ic add 198command is rather restricted, and might be expanded in the future. 199