1.\" $OpenBSD: boot_config.8,v 1.30 2016/03/10 09:04:11 jmc 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: March 10 2016 $ 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 timezone Op Ar minuteswest Op Ar dst 93Change the 94.Va tz 95timezone structure. 96.Va minuteswest 97is the number of minutes west of GMT and 98.Va dst 99is non-zero if Daylight Saving Time is in effect. 100Without arguments, displays its current value. 101.It Ic verbose 102Toggle the autoconfig verbose variable. 103.El 104.Sh EXAMPLES 105The Ethernet card is not detected at boot because the kernel configuration 106does not match the physical hardware configuration, 107e.g. wrong IRQ in OpenBSD/i386. 108The Ethernet card is supposed to use the 109.Xr ne 4 110driver. 111.Bd -literal 112.No UKC> Ic find ne 11324 ne0 at isa0 port 0x240 size 0 iomem 0xd8000 iosiz 0 irq 9 drq -1 drq2 -1 flags 0x0 11425 ne1 at isa0 port 0x300 size 0 iomem -1 iosiz 0 irq 10 drq -1 drq2 -1 flags 0x0 11526 ne* at isapnp0 port -1 size 0 iomem -1 iosiz 0 irq -1 drq -1 flags 0x0 11627 ne* at pci* dev -1 function -1 flags 0x0 11728 ne* at pcmcia* function -1 irq -1 flags 0x0 118UKC> 119.Ed 120.Pp 121ne1 seems to match the configuration except it uses IRQ 5 instead of IRQ 10. 122So the irq on ne1 should be changed via the 123.Fa change 124command. 125The device can be specified by either name or number. 126.Bd -literal 127.No UKC> Ic change ne1 12825 ne1 at isa0 port 0x300 size 0 iomem -1 iosiz 0 irq 10 drq -1 drq2 -1 flags 0x0 129.No change (y/n) \&? Ic y 130.No port [0x300] \&? 131.No size [0] \&? 132.No iomem [-1] \&? 133.No iosiz [0] \&? 134.No irq [10] \&? Ic 5 135.No drq [-1] \&? 136.No drq2 [-1] \&? 137.No flags [0] \&? 13825 ne1 changed 13925 ne1 at isa0 port 0x300 size 0 iomem -1 iosiz 0 irq 5 drq -1 drq2 -1 flags 0x0 140UKC> 141.Ed 142.Pp 143The show command is useful for finding which devices have a certain attribute. 144It can also be used to find those devices with a particular value for 145an attribute. 146.Bd -literal 147.No UKC> Ic show slot 148 2 ahc* at eisa0 slot -1 flags 0x0 149 10 uha* at eisa0 slot -1 flags 0x0 150 12 ep0 at eisa0 slot -1 flags 0x0 151 17 ep* at eisa0 slot -1 flags 0x0 152102 ahb* at eisa0 slot -1 flags 0x0 153103 fea* at eisa0 slot -1 flags 0x0 154.No UKC> Ic show port 0x300 155 25 ne1 at isa0 port 0x300 size 0 iomem -1 iosiz 0 irq 10 drq -1 drq2 -1 flags 0x0 156 72 we1 at isa0 port 0x300 size 0 iomem 0xcc000 iosiz 0 irq 10 drq -1 drq2 -1 flags 0x0 157 75 el0 at isa0 port 0x300 size 0 iomem -1 iosiz 0 irq 9 drq -1 drq2 -1 flags 0x0 158 77 ie1 at isa0 port 0x300 size 0 iomem -1 iosiz 0 irq 10 drq -1 drq2 -1 flags 0x0 159UKC> 160.Ed 161.Pp 162It is possible to add new devices, but only devices that were linked into the 163kernel. 164If a new device is added, following devices will be renumbered. 165.Bd -literal 166.No UKC> Ic find ep 167 11 ep0 at isa0 port -1 size 0 iomem -1 iosiz 0 irq -1 drq -1 drq2 -1 flags 0x0 168 12 ep0 at eisa0 slot -1 flags 0x0 169 13 ep0 at pci* dev -1 function -1 flags 0x0 170 14 ep* at isapnp0 port -1 size 0 iomem -1 iosiz 0 irq -1 drq -1 flags 0x0 171 15 ep* at isa0 port -1 size 0 iomem -1 iosiz 0 irq -1 drq -1 drq2 -1 flags 0x0 172 16 ep* at eisa0 slot -1 flags 0x0 173 17 ep* at pci* dev -1 function -1 flags 0x0 174 18 ep* at pcmcia* dev -1 irq -1 flags 0x0 175.No UKC> Ic add ep1 176.No "Clone Device (DevNo, 'q' or '\&?') \&?" Ic 13 177.No "Insert before Device (DevNo, 'q' or '\&?')" Ic 14 178 14 ep1 at pci* dev -1 function -1 179.No UKC> Ic change 14 180 14 ep1 at pci* dev -1 function -1 181.No change (y/n) \&? Ic y 182.No dev [-1] \&? Ic 14 183.No function [-1] \&? 184.No flags [0] \&? Ic 18 185 14 ep1 changed 186 14 ep1 at pci* dev 14 function -1 flags 0x12 187UKC> 188.Ed 189.Pp 190When configuration is completed, booting can proceed by issuing the 191.Ic quit 192or 193.Ic exit 194commands. 195.Bd -literal 196.No UKC> Ic quit 197Continuing... 198mainbus0 (root) 199.Ed 200.Sh SEE ALSO 201.Xr config 8 202.Sh AUTHORS 203.An Mats O Jansson Aq Mt moj@stacken.kth.se 204.Sh BUGS 205The 206.Ic add 207command is rather restricted, and might be expanded in the future. 208