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diff --git a/static/netbsd/man8/man8.x86/boot.8 b/static/netbsd/man8/man8.x86/boot.8 new file mode 100644 index 00000000..d445bb17 --- /dev/null +++ b/static/netbsd/man8/man8.x86/boot.8 @@ -0,0 +1,1087 @@ +.\" $NetBSD: boot.8,v 1.40 2026/03/11 21:49:26 andvar Exp $ +.\" +.\" Copyright (c) 1991, 1993 +.\" The Regents of the University of California. All rights reserved. +.\" +.\" This code is derived from software written and contributed +.\" to Berkeley by William Jolitz. +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions +.\" are met: +.\" 1. Redistributions of source code must retain the above copyright +.\" notice, this list of conditions and the following disclaimer. +.\" 2. Redistributions in binary form must reproduce the above copyright +.\" notice, this list of conditions and the following disclaimer in the +.\" documentation and/or other materials provided with the distribution. +.\" 3. Neither the name of the University nor the names of its contributors +.\" may be used to endorse or promote products derived from this software +.\" without specific prior written permission. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND +.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE +.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE +.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL +.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS +.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) +.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY +.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF +.\" SUCH DAMAGE. +.\" +.\" @(#)boot_i386.8 8.2 (Berkeley) 4/19/94 +.\" +.Dd October 9, 2025 +.Dt BOOT 8 x86 +.Os +.Sh NAME +.Nm boot +.Nd +system bootstrapping procedures +.Sh DESCRIPTION +Intel Architecture, 32-bit (IA-32) computers (the +.Tn IBM PC +and its clones) +that can run +.Nx Ns /i386 +or +.Nx Ns /amd64 +can use any of the following boot procedures, depending on what the hardware and +.Tn BIOS +support: +.Bl -tag -width "x86/pxeboot(8)" +.It boot +bootstrap +.Nx +from the system +.Tn BIOS +.It efiboot +bootstrap +.Nx +from the system +.Tn UEFI +.It Xr x86/dosboot 8 +bootstrap +.Nx +from +.Tn MS-DOS +.It Xr x86/pxeboot 8 +network bootstrap +.Nx +from a +.Tn TCP/IP +.Tn LAN +with +.Tn DHCP , +.Tn TFTP , +and +.Tn NFS . +.El +.Ss Power fail and crash recovery +Normally, the system will reboot itself at power-up or after crashes. +An automatic consistency check of the file systems will be performed, +and unless this fails, the system will resume multi-user operations. +.Ss Cold starts +The 386 +.Tn "PC AT" +clones attempt to boot the floppy disk drive A (otherwise known as drive +0) first, and failing that, attempt to boot the hard disk C (otherwise +known as hard disk controller 1, drive 0). +The +.Nx +bootblocks are loaded and started either by the +.Tn BIOS , +or by a boot selector program (such as OS-BS, BOOTEASY, the OS/2 Boot Menu or +.Nx Ns 's +.No boot-selecting +master boot record - see +.Xr x86/mbr 8 ) . +.Ss Normal Operation +Once running, a banner similar to the following will appear: +.Bd -literal -offset indent +>> NetBSD BIOS Boot, revision 3.0 +>> (user@buildhost, builddate) +>> Memory: 637/15360 k +Press return to boot now, any other key for boot menu +booting hd0a:netbsd - starting in 5 +.Ed +.Pp +After a countdown, the system image listed will be loaded. +In the example above, it will be +.Dq Li hd0a:netbsd +which is the file +.Pa /netbsd +on partition +.Dq Li a +of the +.Nx +.Tn MBR +partition of the first hard disk known to the +.Tn BIOS +.Po +which is an +.Tn IDE +or similar device \(em see the +.Sx BUGS +section +.Pc . +.Pp +Pressing a key within the time limit, or before the boot program starts, will +enter interactive mode. +When using a short or 0 timeout, it is often useful to interrupt the boot +by holding down a shift key, as some BIOSes and BIOS extensions will drain the +keystroke buffer at various points during POST. +.Pp +If present, the file +.Pa /boot.cfg +will be used to configure the behaviour of the boot loader including +setting the timeout, choosing a console device, altering the banner +text and displaying a menu allowing boot commands to be easily chosen. +See +.Xr boot.cfg 5 . +.Ss Boot Protocol +The +.Nx Ns /x86 +boot loader can boot a kernel using either the native +.Nx +boot protocol, or the +.Dq multiboot +protocol (which is compatible with some other operating systems). +In the native +.Nx +boot protocol, options are passed from the boot loader +to the kernel via flag bits in the +.Va boothowto +variable (see +.Xr boothowto 9 ) . +In the multiboot protocol, options are passed from the boot loader +to the kernel as strings. +.Ss Diagnostic Output +If the first stage boot fails to load the boot, it will print a terse +message indicating the reason for the failure. +The possible error messages and their cause are listed in +.Xr x86/mbr 8 . +.Pp +If the first stage boot succeeds, the banner will be shown and the +error messages should be self-explanatory. +.Ss Interactive mode +In interactive mode, the boot loader will present a prompt, allowing +input of these commands: +.\" NOTE: much of this text is duplicated in the MI boot.8. +.\" Some of it is +.\" also duplicated in the x86-specific x86/dosboot.8 and x86/pxeboot.8; +.\" please try to keep all relevant files synchronized. +.Bl -tag -width 04n -offset 04n +.It Ic boot Oo Ar device Ns Ic \&: Oc Ns Oo Ar filename Oc Oo Fl 1234abcdmqsvxz Oc +The default +.Ar device +will be set to the disk from which the boot loader was loaded. +The partition is set to the first match in this list: +.Bl -enum +.It +The first +.Xr gpt 8 +partition with the +.Va bootme +attribute set. +.It +The partition from which the boot loader was loaded from, if that +can be detected. +.It +The first partition with a file system that could be bootable. +.It +The first partition. +.El +.Pp +To boot from an alternate disk, the full name of the device should +be given at the prompt. +.Ar device +is of the form +.Li NAME= Ns Ar partition_label +when booting from a +.Xr gpt 8 +partitioned disk. +Otherwise, the syntax is +.Xo Ar xd\^ Ns +.Op Ar N\^ Ns Op Ar x +.Xc +where +.Ar xd +is the device from which to boot, +.Ar N +is the unit number, and +.Ar x +is the partition letter. +.Pp +In the latter case, the following list of supported devices may +vary from installation to installation: +.Bl -hang +.It hd +Hard disks as numbered by the BIOS. +This includes ST506, IDE, ESDI, RLL disks on a WD100[2367] or +lookalike controller(s), and SCSI disks +on SCSI controllers recognized by the BIOS. +.It fd +Floppy drives as numbered by the BIOS. +.It cd +CD-ROM drives as numbered by the BIOS. +.It raid +RAIDframe configured from hard disks recognized by the BIOS. +Only RAID level 1 sets are supported by bootstrap code. +If the RAID is partitioned, the first partition is used, or the +first +.Xr gpt 8 +partition that has the +.Va bootme +attribute set. +Inner RAIDframe partitions can also be given to the +.Ic dev +command using he +.Li NAME= Ns Ar partition_label +syntax. +.El +.Pp +The default +.Va filename +is +.Pa netbsd ; +if the boot loader fails to successfully +open that image, it then tries +.Pa netbsd.gz +(expected to be a kernel image compressed by gzip), followed by +.Pa onetbsd , +.Pa onetbsd.gz , +.Pa netbsd.old , +and finally +.Pa netbsd.old.gz . +.Pp +In support of the +.Dv KERNEL_DIR +build option (see +.Xr mk.conf 5 ) , +the boot loader will then try +.Pa netbsd/kernel , +.Pa netbsd/kernel.gz , +.Pa onetbsd/kernel , +.Pa onetbsd/kernel.gz , +.Pa netbsd.old/kernel , +and finally +.Pa netbsd.old/kernel.gz . +Alternate system images can be loaded by just specifying the filename of +the image. +If the specified +.Pa filename +does not contain an embedded or trailing slash character, the boot loader +will also try +.Pa filename/kernel +and +.Pa filename/kernel.gz . +(A leading slash character will be ignored.) +.Pp +Options are: +.Bl -tag -width xxx +.It Fl 1 +Sets the machine-dependent flag +.Dv RB_MD1 +in +.Va boothowto . +In +.Nx Ns /x86 , +this disables multiprocessor boot; +the kernel will boot in uniprocessor mode. +.It Fl 2 +Sets the machine-dependent flag +.Dv RB_MD2 +in +.Va boothowto . +In +.Nx Ns /x86 , +this disables ACPI. +.It Fl 3 +Sets the machine-dependent flag +.Dv RB_MD3 +in +.Va boothowto . +In +.Nx Ns /amd64 , +this disables SVS. +.It Fl 4 +Sets the machine-dependent flag +.Dv RB_MD4 +in +.Va boothowto . +In +.Nx Ns /x86 , +this has no effect. +.It Fl a +Sets the +.Dv RB_ASKNAME +flag in +.Va boothowto . +This causes the kernel to prompt for the root file system device, +the system crash dump device, and the path to +.Xr init 8 . +.It Fl b +Sets the +.Dv RB_HALT +flag in +.Va boothowto . +This causes subsequent reboot attempts to halt instead of rebooting. +.It Fl c +Sets the +.Dv RB_USERCONF +flag in +.Va boothowto . +This causes the kernel to enter the +.Xr userconf 4 +device configuration manager as soon as possible during the boot. +.Xr userconf 4 +allows devices to be enabled or disabled, and allows device locators +(such as hardware addresses or bus numbers) +to be modified before the kernel attempts to attach the devices. +.It Fl d +Sets the +.Dv RB_KDB +flag in +.Va boothowto . +Requests the kernel to enter debug mode, in which it +waits for a connection from a kernel debugger; see +.Xr ddb 4 . +.It Fl m +Sets the +.Dv RB_MINIROOT +flag in +.Va boothowto . +Informs the kernel that a mini-root file system is present in memory. +.It Fl q +Sets the +.Dv AB_QUIET +flag in +.Va boothowto . +Boot the system in quiet mode. +.It Fl s +Sets the +.Dv RB_SINGLE +flag in +.Va boothowto . +Boot the system in single-user mode. +.It Fl v +Sets the +.Dv AB_VERBOSE +flag in +.Va boothowto . +Boot the system in verbose mode. +.It Fl x +Sets the +.Dv AB_DEBUG +flag in +.Va boothowto . +Boot the system with debug messages enabled. +.It Fl z +Sets the +.Dv AB_SILENT +flag in +.Va boothowto . +Boot the system in silent mode. +.El +.It Ic consdev Ar dev\| Ns Oo Ns Ic \&, Ns Ar speed Oc +[Not available for +.Xr x86/dosboot 8 ] +Immediately switch the console to the specified device +.Ar dev +and reprint the banner. +.Ar dev +must be one of +.\" .Bl -item -width com[0123]kbd -offset indent -compact +.Li pc , com0 , com1 , com2 , +.Li com3 , com0kbd , com1kbd , com2kbd , +.Li com3kbd , +or +.Li auto . +See +.Sx Console Selection Policy +in +.Xr x86/boot_console 8 . +.Pp +A +.Ar speed +for the serial port is optional and defaults to 9600. +If a value of zero is specified, then the current baud rate (set by the +BIOS) will be used. +Setting the +.Ar speed +with the +.Li pc +device is not possible. +.Pp +UEFI may support some USB and PCI-based serial ports. +See the +.Sx UEFI serial ports +section for details. +Using the +.Ic consdev +command without arguments lists the available ports. +.Ar com0 +to +.Ar com3 +are reserved for standard ISA serial ports, other ports are assigned to +.Ar com4 +and beyond. +The generic +.Ar com{unit}[,speed] +syntax can be used to select any port. +.Pp +Bootstrap can tell the kernel to use a USB-to-serial adapter for console +using the +.Ar ucom{unit}[,speed] +syntax. +No console switch happens in bootstrap, and kernel +console initialization will be deferred after USB devices attachment. +This means early boot will be silent, and +.Xr userconf 4 +interactive mode cannot be used. +The default +.Ar ucom +speed is 115200. +.It Ic kconsdev Ar dev\| Ns Oo Ns Ic \&, Ns Ar speed Oc +Configure the kernel console like +.Ic consdev +but do not attempt to switch console in bootstrap. +This is useful when using a USB-to-serial adapter that is known as a +.Ar com +device in bootstrap but as a +.Ar ucom +device for the kernel. +One may use a syntax like: +.Bd -literal -offset indent +consdev com4,115200 +kconsdev ucom0,115200 +.Ed +Note that command ordering matters. +.It Ic dev Op Ar device +Set the default drive and partition for subsequent file system +operations. +Without an argument, print the current setting. +.Ar device +is of the form specified in +.Ic boot . +.It Ic devpath +[Only available for UEFI boot] Dump UEFI device paths. +.It Ic efivar +[Only available for UEFI boot] Dump UEFI environment variables from NVRAM. +.It Ic fs Ar file +[Only available for BIOS and UEFI boot] +Load a file system image from the specified +.Ar file , +and request the kernel to use it as the root file system. +The +.Xr makefs 8 +utility may be used to create suitable file system images. +.It Ic gop Op Va mode_index +[Only available for UEFI boot] Without argument, list the available +video modes. If an argument is given, select a video mode. +.It Ic help +Print an overview about commands and arguments. +.It Ic load Ar module Op Ar arguments +[Not available for +.Xr x86/dosboot 8 ] +Load the specified kernel +.Ar module , +and pass it the specified +.Ar arguments . +If the module name is not an absolute path, +.Bd -ragged -offset indent -compact +.Pa /stand/ Ns Xo Ns +.Aq Ar arch Ns +.Pa / Ns +.Aq Ar osversion Ns +.Pa /modules/ Ns +.Aq Ar module Ns +.Pa / Ns +.Aq Ar module Ns +.Pa .kmod +.Xc +.Ed +is used. +Possible uses of the +.Ic load +command include loading a memory disk image before booting a kernel, +or loading a +.Tn Xen +DOM0 kernel before booting the +.Tn Xen +hypervisor. +See +.Xr boot.cfg 5 +for examples. +.Pp +In addition to the +.Cm boot +options specified above, the +.Tn Xen +DOM0 kernel accepts +.Po Ar arguments +being separated with spaces +.Pc : +.Bl -tag -width xxx +.It Ic bootdev Ns = Ns Ar dev Po or Ic root Ns = Ns Ar dev Pc +Override the default boot device. +.Ar dev +is of the form +.Li NAME= Ns Ar partition_label +for +.Xr gpt 8 +partitioned disks. +It can also be a unit name +.Pq Ql wd0 , +or an interface name +.Po Ql bge0 , +.Ql wm0 , +\&... +.Pc +for cases where the root file system has to be loaded +from network (see the +.Sx BUGS +section in +.Xr x86/pxeboot 8 ) . +.It Ic console Ns = Ns Ar dev +Console used by DOM0 kernel during boot. +.Ar dev +accepts the same values as the ones given for the +.Cm consdev +command. +See +.Sx Console Selection Policy +in +.Xr x86/boot_console 8 . +.It Xo Ic ip Ns Li \&= Ns +.Ar my_ip Ns Li \&: Ns Ar serv_ip Ns Li \&: Ns Ar gw_ip Ns Li \&: Ns +.Ar mask Ns Li \&: Ns Ar host Ns Li \&: Ns Ar iface +.Xc +Specify various parameters for a network boot (IPs are in +dot notation), +each one separated by a colon: +.Bl -tag -width xxxxxxx +.It Ar my_ip +address of the host +.It Ar serv_ip +address of the NFS server +.It Ar gw_ip +address of the gateway +.It Ar mask +network mask +.It Ar host +address of the host +.It Ar iface +interface +.Po e.g., Dq Li xennet0 +or +.Dq Li eth0 +.Pc +.El +.It Ic nfsroot Ns = Ns Ar address Ns Li \&: Ns Ar rootpath +Boot the system with root on NFS. +.Ar address +is the address of the NFS server, and +.Ar rootpath +is the remote mount point for the root file system. +.It Ic pciback.hide Ns = Ns Ar pcidevs +Pass a list of PCI IDs for use with the PCI backend driver, +.Xr pciback 4 . +.Ar pcidevs +is formed of multiple IDs (in +.Ar bus Ns Li \&: Ns Ar device Ns Li \&. Ns Ar function +notation), +each ID being surrounded with brackets. +PCI domain IDs are currently ignored. +See +.Xr pciback 4 . +.El +.It Ic ls Op Ar path +[Not available for +.Xr x86/pxeboot 8 ] +Print a directory listing of +.Ar path , +containing inode number, filename, and file type. +.Ar path +can contain a device specification. +.It Ic memmap +[Only available for UEFI boot] Dump UEFI memory map. +.It Ic menu +[Only available for BIOS and UEFI boot] +Display the boot menu and initiate a countdown, +similarly to what would have happened if interactive mode +had not been entered. +.It Ic modules Bro Li \^on \ + No \(or Li off \ + No \(or Li enabled \ + No \(or Li disabled\^ \ + Brc +[Not available for +.Xr x86/dosboot 8 ] +The values +.Ql enabled , +.Ql on +will enable module loading for +.Ic boot +and +.Ic multiboot , +whereas +.Ql disabled , +.Ql off +will turn off the feature. +.It Ic mode Va fstype +[Only available for +.Xr x86/dosboot 8 ] +Switch file system type; +.Va fstype +should be one of +.Ar dos +or +.Ar ufs . +.It Ic multiboot Ar kernel Op Ar arguments +[Not available for +.Xr x86/dosboot 8 ] +Boot the specified +.Ar kernel , +using the +.Dq multiboot +protocol instead of the native +.Nx +boot protocol. +The +.Ar kernel +is specified in the same way as with the +.Ic boot +command. +.Pp +The multiboot protocol may be used in the following cases: +.Bl -tag -width indent +.It Nx Ns / Ns Xen No kernels +The +.Tn Xen +DOM0 kernel must be loaded as a module using the +.Ic load +command, and the +.Tn Xen +hypervisor must be booted using the +.Ic multiboot +command. +Options for the DOM0 kernel (such as +.Dq -s +for single user mode) must be passed as options to the +.Ic load +command. +Options for the hypervisor (such as +.Dq Li dom0_mem=256M +to reserve +.Pf 256 Tn MB +of memory for DOM0) +must be passed as options to the +.Ic multiboot +command. +See +.Xr boot.cfg 5 +for examples on how to boot +.Nx Ns / Ns Xen. +.It Nx No multiboot kernels +A +.Nx +kernel that was built with +.Cd options MULTIBOOT +(see +.Xr x86/multiboot 8 ) +may be booted with either the +.Ic boot +or +.Ic multiboot +command, passing the same +.Ar arguments +in either case. +.It Non- Ns Nx No kernels +A kernel for a +.No non- Ns Nx +operating system that expects to be booted using the +multiboot protocol (such as by the GNU +.Dq GRUB +boot loader) +may be booted using the +.Ic multiboot +command. +See the foreign operating system's documentation for the available +.Ar arguments . +.El +.It Ic pkboot +[Only available for BIOS and UEFI boot] Boot a kernel that has +the +.Cd KASLR +option set, for Kernel Address Space Layout Randomizaton. +.It Ic quit +Reboot the system. +.It Ic reloc Op Va default No \(or Va none No \(or Va address +[Only UEFI boot] Sets where the kernel is copied by bootstrap +before it is started. Values other than default require a kernel +built with the +.Cd SELFRELOC +option, so that can relocate itself at the right address, +otherwise a crash occurs at boot time. +.Bl -tag -width default +.It Va default +Copy the kernel at ELF header load address, this is the historical +behavior. +.It Va none +Leave the kernel where it was loaded and start it as is. +.It Va address +Copy the kernel at given +.Va address . +.El +.It Ic rndseed Ar file +[Only available for BIOS and UEFI boot] +Load the specified +.Ar file +and request the kernel to use it as a seed for the +.Xr rnd 4 +random number generator. +The +.Ar file +should be in the private format used by +.Xr rndctl 8 , +and should have been saved by +.Ql "rndctl -S" +shortly before the previous shutdown. +See the +.Va random_seed +and +.Va random_file +variables in +.Xr rc.conf 5 , +and the +.Pa /etc/rc.d/random_seed +script, for a way to manage the seed file. +Using the same seed file on more then one host, +or for more than one boot on the same host, +will reduce the quality of random numbers +and may impact system security. +.It Ic root Ar spec +[Only available for BIOS and UEFI boot] +Pass an explicit root specification to the kernel. +See BTINFO_ROOTDEVICE for details. +.It Ic splash Ar file +[Only available for BIOS and UEFI boot] +Load a graphical image from the specified +.Ar file +and request the kernel to use it as a splash screen. +The +.Ar file +should contain an image in one of these formats: +JPEG (baseline only, not progressive), +PNG (8-bit only), +TGA, +BMP (non-1bpp, non-RLE), +GIF, +PSD (composited view only), +or +PIC. +.It Ic text Op Va mode_index +[Only available for UEFI boot] Without argument, list the available +text modes (displayed as column x line in hexadecimal, therefore +.Li 50x19 +means +.Li 80 +columns and +.Li 25 +lines). With an argument, select a text mode. +.It Ic userconf Ar command +[Not available for +.Xr x86/dosboot 8 ] +Pass command +.Ar command +to +.Xr userconf 4 +at boot time. +These commands are processed before the interactive +.Xr userconf 4 +shell is executed, if requested. +.It Ic version Op Ar full +[Only available for UEFI boot] Display UEFI bootstrap version. With the +.Op full +argument, also display information about UEFI itself. +.It Ic vesa Bro Ar \^modenum \ + No \(or Li on \ + No \(or Li off \ + No \(or Li enabled \ + No \(or Li disabled \ + No \(or Li list Brc +[Only available for BIOS and +.Xr x86/pxeboot 8 ] +Initialise the video card to the specified resolution and bit depth. +The +.Ar modenum +should be in the form of +.Ql 0x100 , +.Ql 800x600 , +.Ql 800x600x32 . +The values +.Ql enabled , +.Ql on +put the display into the default mode, and +.Ql disabled , +.Ql off +returns the display into standard vga mode. +The value +.Ql list +lists all supported modes. +.El +.Pp +In an emergency, the bootstrap methods described in the +.Nx +installation notes for the x86 architectures +can be used to boot from floppy or other media, +or over the network. +.Ss Locating the root file system +The kernel uses information from the bootloader to locate the +file system to mount as root. +There are three methods: +.Bl -tag -width 04n -offset 04n +.\" XXX: what this .Va is supposed to mean? +.It Dv BTINFO_ROOTDEVICE Va from +.Xr boot.cfg 5 +or multiboot. +The bootloader passes the root device name as driver, unit, and +partition (like +.Ql sd0a Ns ). +This will be automatically substituted by a +.Xr dk 4 +wedge if one is discovered. +.Pp +If the bootloader passes a wedge name as +.Dq Li wedge: +or +.Dq Li NAME= +followed by the name. +The kernel will search for a +.Xr dk 4 +device with that name. +.It Dv BTINFO_BOOTWEDGE Va determined by bootblock +The bootloader passes start offset and length of a hard disk partition +and a offset, size and hash of a +.Dq boot area . +Then kernel searches +all disks and wedges for a block sequence at that offset with a +matching hash. +If one is found, the kernel will look for a wedge +on that device at the same offset. +.Pp +An additional partition number is provided if the bootloader also +passed a +.Dv BTINFO_BOOTDISK +record. +This (or partition +.Ql a ) +will be used +by the kernel as a fallback if there is no matching wedge. +.It Dv BTINFO_BOOTDISK Va determined by bootblock +This uses the device number passed by the +.Tn BIOS +that distinguishes between floppy, hard drive and +.Tn CD-ROM +boot. +.Bl -tag -width xxx +.It Floppy +The kernel searches for the +.Xr fd 4 +device with the correct unit, the partition number is used +to select a specific disk format. +See +.Xr fd 4 +for details. +.It Hard drive +The bootloader passed a partition number and disklabel +data (offset, type, checksum, packname). +The kernel searches +all disks for a matching disklabel. +If one is found, the +kernel will use that device and partition number. +.It Tn CDROM +The +.Tn BIOS +does not distinguish between multiple +.Tn CD +devices. +The kernel searches for the first +.Xr cd 4 +device. +So you can only boot from unit 0. +.El +.El +.Sh UEFI serial ports +Serial ports supported by a UEFI driver can be used in UEFI +and in NetBSD bootstrap. +UEFI usually supports ISA serial ports, and it may support PCI or USB-to- +serial adapters, depending on vendor-specific implementations. +.Pp +An open source UEFI driver is available form Tianocore EDK2, +for USB-to-serial adapters using the FTDI FT232R chip. +USB vendor ID and product ID for those devices are +.Ar 0x0403 +and +.Ar 0x6001. +.Pp +To use it, obtain the +.Pa FtdiUsbSerialDxe.efi +driver from Tianocore EDK2 and save it in the EFI bootstrap partition, +for instance in +.Pa /EFI/EDK2/FtdiUsbSerialDxe.efi +then create a +.Pa /EFI/boot/startup.nsh +script containing something like +.Bd -literal -offset indent +FS0: +load \\EFI\\EDK2\\FtdiUsbSerialDxe.efi +bootx64.efi +.Ed +.Pp +Then make sure UEFI boots into the UEFI shell. +If it is not available in the built-in options, +.Pa Shell.efi +can be obtained from Tianocore EDK2 and installed in +.Pa /EFI/boot/Shell.efi . +.Sh FILES +.Bl -tag -width /usr/mdec/bootxx_fstype -compact +.It Pa /boot +boot program code loaded by the primary bootstrap +.It Pa /boot.cfg +optional configuration file +.It Pa /netbsd +system code +.It Pa /netbsd.gz +gzip-compressed system code +.It Pa /usr/mdec/boot +master copy of the boot program (copy to /boot) +.It Pa /usr/mdec/bootxx_fstype +primary bootstrap for file system type fstype, copied to the start of +the +.Nx +partition by +.Xr installboot 8 . +.It Pa /usr/mdec/bootia32.efi +.It Pa /usr/mdec/bootx64.efi +.Tn UEFI +bootstraps for +.Nx Ns /i386 +and +.Nx Ns /amd64 , +which should be copied to the +.Pa /EFI/boot +directory in a +.Tn FAT +formatted partition of type +.Tn EFI +(either +.Xr x86/mbr 8 +or +.Xr gpt 8 , +see the +.Sx BUGS +section). +.Nx +.Tn UEFI +bootstrap reads its configuration from the +.Pa /EFI/NetBSD/boot.cfg +file in the +.Tn EFI +partition. +.El +.Sh SEE ALSO +.Xr ddb 4 , +.Xr fd 4 , +.Xr pciback 4 , +.Xr userconf 4 , +.Xr boot.cfg 5 , +.Xr halt 8 , +.Xr installboot 8 , +.Xr reboot 8 , +.Xr rescue 8 , +.Xr shutdown 8 , +.Xr x86/boot_console 8 , +.Xr x86/dosboot 8 , +.Xr x86/mbr 8 , +.Xr x86/multiboot 8 , +.Xr x86/pxeboot 8 , +.Xr boothowto 9 +.Sh BUGS +The kernel file name must be specified before, not after, the boot options. +Any +.Ar filename +specified after the boot options, e.g.: +.Pp +.Dl boot -d netbsd.test +.Pp +is ignored, and the default kernel is booted. +.Pp +Hard disks are always accessed by +.Tn BIOS +functions. +Unit numbers are +.Tn BIOS +device numbers which might differ from numbering in the +.Nx +kernel or physical parameters +.Po +e.g., +.Tn SCSI +slave numbers +.Pc . +There isn't any distinction between +.Dq sd +and +.Dq wd +devices at the bootloader level. +This is less a bug of the bootloader code than +a shortcoming of the PC architecture. +The default disk device's name printed in the starting message +is derived from the +.Dq type +field of the +.Nx +disklabel (if it is a hard disk). +.Pp +.Tn UEFI +implementations are supposed to support either +.Xr x86/mbr 8 +or +.Xr gpt 8 +partitioning, but some do not handle the latter. +.Tn UEFI +booting +from a +.Xr gpt 8 +partitioned disk is still possible in this case, by adding +an overlapping +.Tn EFI +partition in the protective +.Xr x86/mbr 8 +block. +This can be achieved using the following commands +(you must adapt the hard disk and +.Tn EFI +partition start end size to fit your setup): +.Bd -literal -offset indent +dd if=/dev/rwd0d bs=512 count=1 of=mbr +fdisk -FIfaui1s 4/34/32768 -c /usr/mdec/mbr mbr +dd if=mbr bs=512 count=1 of=/dev/rwd0d conv=notrunc +.Ed +.Pp +The resulting +.Xr x86/mbr 8 +partition table will look like this: +.Bd -literal -offset indent +0: GPT Protective MBR (sysid 238) + start 1, size 2097151 (1024 MB, Cyls 0-130/138/8) + PBR is not bootable: Bad magic number (0x0000) +1: Primary DOS with 16 bit FAT <32M (sysid 4) + start 34, size 32768 (16 MB, Cyls 0/0/35-2/10/42), Active +2: <UNUSED> +3: <UNUSED> +.Ed |