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<?xml version="1.0" encoding="UTF-8"?>
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<title>GXemul: SGI O2 emulation</title>
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<h1>GXemul: SGI O2 emulation</h1>
<p>
<a href="./">Back to the index.</a>
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<p>The SGI O2 emulation mode tries to emulate enough of the main MIPS
processor and other peripherals of a real
<a href="http://en.wikipedia.org/wiki/SGI_O2">SGI O2</a> machine, to be
able to boot guest OSes.
<p>
Emulated hardware:
<ul>
<li>MIPS R10000 main CPU.
<li>RAM: Up to 256 MB works well, up to 1 GB (max of what a real O2 can handle) works with OpenBSD/sgi (and possibly the raw PROM)
<li>Interrupt controllers, etc.
<li>Serial port
<li>On-board O2 graphics; works well enough to run NetBSD/sgimips with X11.
<li>PS/2 Keyboard and mouse
<li>Ethernet, enough to (barely) run OpenBSD and NetBSD with root-on-nfs.
</ul>
<p>Things not yet emulated include: SCSI, audio/video boards, the VICE chipset, ...
<p>This page contains instructions for how to install and run:
<ul>
<li><a href="#netbsdsgimips">NetBSD/sgimips</a>
<li><a href="#openbsdsgiinstall">OpenBSD/sgi</a>
<li><small><a href="#linuxforo2"><font color="red">Linux for O2</font></a> (not yet)</small>
<li><small><a href="#IRIX"><font color="red">IRIX</font></a> (not yet)</small>
</ul>
<p>and also some hints on how to make a <a href="#prom">backup copy of the PROM</a> from your own O2 and run it in the emulator.
<p><br>
<a name="netbsdsgimips"></a>
<h3>NetBSD/sgimips:</h3>
<p>
<a href="20060623-netbsd-sgimips-3.0.png"><img src="20060623-netbsd-sgimips-3.0_small.png"></a>
<a href="20190612-netbsd-sgimips-1.png"><img src="20190612-netbsd-sgimips-1_small.png"></a>
<a href="20190612-netbsd-sgimips-2.png"><img src="20190612-netbsd-sgimips-2_small.png"></a>
<p><a href="http://www.netbsd.org/ports/sgimips/">NetBSD/sgimips</a> can run
in GXemul on an emulated SGI O2 (also known as IP32). The SCSI controller
is not emulated yet, so NetBSD needs to boot with root-on-NFS:
<p>
<ol>
<li>First of all, an "<tt>nfs server</tt>" machine must be set up.
This needs to have a 4000 MB <tt>/tftpboot</tt> partition.
<a href="machine_decstation.html#netbsdpmaxinstall">Install NetBSD/pmax 8.0 from CDROM</a>.
Do not configure the network and do not install any X11 packages on the
nfs server, as they are not needed.
<i>Don't forget to add the extra partition!</i>
<p>
<li>Download the files corresponding to a NetBSD/sgimips CD-ROM iso image, and the
GENERIC and INSTALL kernels:<pre>
<a href="ftp://ftp.NetBSD.org/pub/NetBSD/NetBSD-8.0/sgimips/binary/kernel/netbsd-GENERIC32_IP3x.gz">ftp://ftp.NetBSD.org/pub/NetBSD/NetBSD-8.0/sgimips/binary/kernel/netbsd-GENERIC32_IP3x.gz</a>
<a href="ftp://ftp.NetBSD.org/pub/NetBSD/NetBSD-8.0/sgimips/binary/kernel/netbsd-INSTALL32_IP3x.gz">ftp://ftp.NetBSD.org/pub/NetBSD/NetBSD-8.0/sgimips/binary/kernel/netbsd-INSTALL32_IP3x.gz</a>
wget -np -l 0 -r <a href="ftp://ftp.netbsd.org/pub/NetBSD/NetBSD-8.0/sgimips/binary/sets/">ftp://ftp.netbsd.org/pub/NetBSD/NetBSD-8.0/sgimips/binary/sets/</a>
mkisofs -U -o sgimips.iso ftp.netbsd.org/pub/NetBSD/NetBSD-8.0
</pre>
<li>Start the DECstation emulation:<pre>
<b>gxemul -e 3max -d nbsd_pmax.img -d sgimips.iso</b>
</pre>Log in as root, configure the pmax machine as an NFS server,
and extract the files from the sgimips CD-ROM image:
<p><table border="0"><tr><td><tt> </tt></td><td><pre>
<b>echo hostname=server >> /etc/rc.conf
echo ifconfig_le0=\"inet 10.0.0.2\" >> /etc/rc.conf
echo nameserver 10.0.0.254 >> /etc/resolv.conf
echo 10.0.0.254 > /etc/mygate
echo /tftpboot -maproot=root 10.0.0.1 > /etc/exports
echo rpcbind=YES >> /etc/rc.conf
echo nfs_server=YES >> /etc/rc.conf
echo mountd=YES >> /etc/rc.conf
echo bootparamd=YES >> /etc/rc.conf
printf "client root=10.0.0.2:/tftpboot \\\n swap=10.0.0.2:/tftpboot/swap\n" > /etc/bootparams
echo "bootps dgram udp wait root /usr/sbin/bootpd bootpd -d 4 -h 10.0.0.2" >> /etc/inetd.conf
cat >> /etc/bootptab
client:\
:ht=ether:\
:ha=082030000010:\
:sm=255.0.0.0:\
:lg=10.0.0.254:\
:ip=10.0.0.1:\
:rp=/tftpboot:
</b>(press CTRL-D)
<b>echo "08:20:30:00:00:10 client" > /etc/ethers
echo 10.0.0.1 client > /etc/hosts
cd /tftpboot; mount /dev/cd0a /mnt
for a in /mnt/*/binary/sets/[bcegmtx]*.tgz; do echo $a; tar zxfp $a; done
echo 10.0.0.2:/tftpboot / nfs rw 0 0 > /tftpboot/etc/fstab
echo rc_configured=YES >> /tftpboot/etc/rc.conf
echo 10.0.0.254 >> /tftpboot/etc/mygate
echo nameserver 10.0.0.254 >> /tftpboot/etc/resolv.conf
echo rc_configured=YES >> /tftpboot/etc/rc.conf
dd if=/dev/zero of=swap bs=1024 count=262144
cd /; umount /mnt; halt</b>
</pre></td></tr></table>
<p>
<li>Create a configuration file called <tt>config_client</tt>:
<table border="0"><tr><td><tt> </tt></td><td><pre>
<font color="#2020cf">! Configuration file for running NetBSD/sgimips diskless with
! a NetBSD/pmax machine as the nfs server.</font>
<b>net(
add_remote("localhost:12444") </b>! the server<b>
local_port(12445) </b>! the client<b>
)
machine(
name("client machine")
serial_nr(1)
type("sgi")
subtype("o2")
use_x11(1)
memory(256)
load("netbsd-INSTALL32_IP3x.gz")</b>
! load("netbsd-GENERIC32_IP3x.gz")<b>
)
</b>
</pre></td></tr></table>
... and another configuration file for the server,
<tt>config_server</tt>:
<table border="0"><tr><td><tt> </tt></td><td><pre>
<b>net(
local_port(12444) </b>! the server<b>
add_remote("localhost:12445") </b>! the client<b>
)
machine(
name("nfs server")
serial_nr(2)
type("dec")
subtype("5000/200")
disk("nbsd_pmax.img")
)
</b>
</pre></td></tr></table>
<li>Boot the "<tt>nfs server</tt>" and the NetBSD/sgimips
"<tt>client machine</tt>" as two separate emulator instances:<pre>
in one xterm:
<b>gxemul @config_server</b>
and then, in another xterm:
<b>gxemul @config_client</b>
</pre>
<li>In the NetBSD/sgimips window, choose "<tt>x: Exit Install System</tt>"
in the installer's main menu, and then type:<pre>
<b>ifconfig mec0 10.0.0.1; route add default 10.0.0.254</b>
<b>mount -v 10.0.0.2:/tftpboot /mnt</b>
<b>cd /mnt/dev; ./MAKEDEV all; cd /; umount /mnt</b>
<b>halt</b>
</pre>Then, once the client machine has halted, log in as <tt>root</tt>
on the server machine and type <tt><b>reboot</b></tt>.
<p>
<li>Once everything has been set up correctly, change
<tt>netbsd-INSTALL32_IP3x.gz</tt> in <tt>config_client</tt> to
<tt>netbsd-GENERIC32_IP3x.gz</tt> (the GENERIC kernel).
</ol>
<p>You might want to log in as <tt>root</tt> on the server machine, and
run <tt>tcpdump -lnvv</tt> or similar, to see that what the client machine
actually does on the network.
<p>It should now be possible to boot NetBSD/sgimips using the NetBSD/pmax
nfs server, using the following commands: (NOTE! Execute these two
commands in separate xterms!)<pre>
<b>gxemul @config_server</b>
<b>gxemul @config_client</b>
</pre>
<p>If/when asked for "<tt>root device:</tt>" etc. on the client machine, enter
the following values:<pre>
root device: <b>mec0</b>
dump device: <b>(leave blank)</b>
file system (default generic): <b>(leave blank)</b>
..
init path (default /sbin/init): <b>(leave blank)</b>
Enter pathname of shell or RETURN for /bin/sh: <b>(leave blank)</b>
Terminal type? [unknown] <b>xterm</b>
..
# <b>exit</b> (to leave the single-user shell)
</pre>
<p>Note: Netbooting like this is very slow, so you need a lot of patience.
<p><br>
<a name="openbsdsgiinstall"></a>
<h3>OpenBSD/sgi:</h3>
<p><a href="http://www.openbsd.org/sgi.html">OpenBSD/sgi</a>
can run in GXemul on an emulated O2 (SGI-IP32), with root on NFS.
<p><a href="https://www.openbsd.org/sgi.html">https://www.openbsd.org/sgi.html</a>
says <i>"The OpenBSD/sgi port was discontinued after the 6.7 release"</i>, but
it seems that 6.8 is available from the official FTP site anyway.
<p>
<a href="20050617-openbsd-sgi.png"><img src="20050617-openbsd-sgi_small.png"></a>
<a href="20181018-openbsd-sgi-o2.png"><img src="20181018-openbsd-sgi-o2-small.png"></a>
<a href="openbsd-sgi-x-20210220.png"><img src="openbsd-sgi-x-20210220-small.png"></a>
<p>GXemul does not yet emulate the AHC PCI SCSI controller in the O2,
so it needs to boot via the emulated network.
Another emulated machine must then be used as the nfs root server, and the emulated O2 machine must boot
as a <a href="http://man.openbsd.org/diskless">diskless</a>
client. Performing this setup is quite time consuming, but necessary:
<p>
<ol>
<li>First of all, the "<tt>nfs server</tt>" machine must be set up.
<a href="machine_decstation.html#netbsdpmaxinstall">Install NetBSD/pmax 8.0 from CDROM</a>,
perform a default install from CDROM without configuring the
network, but add a 4000 MB <tt>/tftpboot</tt> partition when
configuring the disk!
<p>
<li>On the host, download the OpenBSD distribution:
<p><table border="0"><tr><td><tt> </tt></td><td><pre>wget http://ftp.eu.openbsd.org/pub/OpenBSD/6.8/sgi/base68.tgz
wget http://ftp.eu.openbsd.org/pub/OpenBSD/6.8/sgi/comp68.tgz
wget http://ftp.eu.openbsd.org/pub/OpenBSD/6.8/sgi/xbase68.tgz
wget http://ftp.eu.openbsd.org/pub/OpenBSD/6.8/sgi/xfont68.tgz
wget http://ftp.eu.openbsd.org/pub/OpenBSD/6.8/sgi/xserv68.tgz
wget http://ftp.eu.openbsd.org/pub/OpenBSD/6.8/sgi/xshare68.tgz
</pre></td></tr></table>
<li>Start the emulation of the DECstation NFS server using this command line:
<p><table border="0"><tr><td><tt> </tt></td><td><pre>gxemul -xe 3max -d nbsd_pmax.img -d base68.tgz -d comp68.tgz -d xbase68.tgz -d xfont68.tgz -d xserv68.tgz -d xshare68.tgz
</pre></td></tr></table>
and enter the following commands to configure the server for NFS serving and
extract the OpenBSD distribution:
<table border="0"><tr><td><tt> </tt></td><td><pre>
<b>echo hostname=server >> /etc/rc.conf
echo ifconfig_le0=\"inet 10.0.0.2\" >> /etc/rc.conf
echo nameserver 10.0.0.254 >> /etc/resolv.conf
echo 10.0.0.254 > /etc/mygate
echo /tftpboot -maproot=root -alldirs 10.0.0.1 > /etc/exports
echo rpcbind=YES >> /etc/rc.conf
echo nfs_server=YES >> /etc/rc.conf
echo mountd=YES >> /etc/rc.conf
echo bootparamd=YES >> /etc/rc.conf
printf "client root=10.0.0.2:/tftpboot swap=10.0.0.2:/tftpboot/swap\n" > /etc/bootparams
echo "08:20:30:00:00:10 client" > /etc/ethers
echo 10.0.0.1 client > /etc/hosts
cd /tftpboot
tar xzf /dev/sd1c
tar xzf /dev/sd2c
tar xzf /dev/sd3c
tar xzf /dev/sd4c
tar xzf /dev/sd5c
tar xzf /dev/sd6c
tar zxfv var/sysmerge/etc.tgz
tar zxfv var/sysmerge/xetc.tgz
chmod 1777 tmp
dd if=/dev/zero of=swap bs=1024 count=262144
echo inet 10.0.0.1 > /tftpboot/etc/hostname.mec0
chmod 640 /tftpboot/etc/hostname.mec0
echo 10.0.0.254 > /tftpboot/etc/mygate
echo nameserver 10.0.0.254 > /tftpboot/etc/resolv.conf
echo 10.0.0.2:/tftpboot / nfs rw 0 0 > /tftpboot/etc/fstab
echo 10.0.0.2:/tftpboot/swap none swap sw,nfsmntpt=/swap >> /tftpboot/etc/fstab
halt</b>
</pre></td></tr></table>
<li>Download the OpenBSD/sgi GENERIC and RAMDISK kernels:<pre>
<a href="http://ftp.eu.openbsd.org/pub/OpenBSD/6.8/sgi/bsd.IP32">http://ftp.eu.openbsd.org/pub/OpenBSD/6.8/sgi/bsd.IP32</a>
<a href="http://ftp.eu.openbsd.org/pub/OpenBSD/6.8/sgi/bsd.rd.IP32">http://ftp.eu.openbsd.org/pub/OpenBSD/6.8/sgi/bsd.rd.IP32</a>
</pre>
<li>Create a configuration file called <tt>config_client</tt>:
<table border="0"><tr><td><tt> </tt></td><td><pre>
<font color="#2020cf">! Configuration file for running OpenBSD/sgi diskless with
! a NetBSD/pmax machine as the nfs server.
!
! This config file is for the client.</font>
<b>net(
add_remote("localhost:12444") </b>! the server<b>
local_port(12445) </b>! the client<b>
)
machine(
name("client machine")
serial_nr(1)
type("sgi")
subtype("o2")
use_x11(1)
memory(1024)
load("bsd.rd.IP32")
! load("bsd.IP32")
)
</b>
</pre></td></tr></table>
... and another configuration file for the server,
<tt>config_server</tt>:
<table border="0"><tr><td><tt> </tt></td><td><pre>
<b>net(
local_port(12444) </b>! the server<b>
add_remote("localhost:12445") </b>! the client<b>
)
machine(
name("nfs server")
serial_nr(2)
type("dec")
subtype("5000/200")
disk("nbsd_pmax.img")
)
</b>
</pre></td></tr></table>
<li>Boot the "<tt>nfs server</tt>" and the OpenBSD/sgi
"<tt>client machine</tt>" as two separate emulator instances:<pre>
in one xterm:
<b>gxemul @config_server</b>
and then, in another xterm:
<b>gxemul @config_client</b>
</pre>
<li>In the emulated OpenBSD/sgi client, type 's' for Shell and run these commands:
<table border="0"><tr><td><tt> </tt></td><td><pre>
<b>ifconfig mec0 10.0.0.1; route add default 10.0.0.254
mount -v 10.0.0.2:/tftpboot /mnt
cd /mnt/dev; ./MAKEDEV all; cd /; umount /mnt
reboot</b>
</pre></td></tr></table>
<li>Change bsd.rd.IP32 to bsd.IP32 in the client configuration file.
<li>Finally, run the client again:<pre>
<b>gxemul @config_client</b>
</pre><p>If the root device is not auto-detected, enter <tt>mec0</tt>.
</ol>
<p>Log in as root, with empty password.
To start X11, type <tt>startx</tt>.
Note that the emulation is a bit slow, mostly due to having the file
system on NFS.
<p><br>
<a name="linuxforo2"></a>
<h3>Linux for O2</h3>
<p><font color="red">NOTE: This does not work yet. Some old kernels may work,
but I have not had the time to set up NFS netbooting so I don't know
whether that would really work, or trigger other bugs.</font>
<p>Some kernels (Linux 2.5 and 2.6) from the years 2002 - 2004 can be found here: <a href="https://www.linux-mips.org/~glaurung/">https://www.linux-mips.org/~glaurung/</a>
<br>Other kernels here: <a href="http://ftp.debian.org/debian/dists/Debian8.11/main/installer-mips/current/images/r5k-ip32/">Debian Linux for O2</a>
<p>Example with <a href="https://www.linux-mips.org/~glaurung/O2/linux-2.5.47/kernel/vmlinux64-r10k">https://www.linux-mips.org/~glaurung/O2/linux-2.5.47/kernel/vmlinux64-r10k</a> (launced using <tt>gxemul -X -e o2 vmlinux64-r10k</tt>):
<p>
<a href="20190715-sgi-o2-linux.png"><img src="20190715-sgi-o2-linux-small.png"></a>
<p>Another kernel to try could be:
<a
href="http://mirrors.telepoint.bg/debian/dists/stretch/main/installer-mips/20150718/images/r5k-ip32/netboot-boot.img">http://mirrors.telepoint.bg/debian/dists/stretch/main/installer-mips/20150718/images/r5k-ip32/netboot-boot.img</a>
<p><br>
<a name="IRIX"></a>
<h3>Experimenting with booting IRIX from a real SGI O2</h3>
<p><font color="red">NOTE: This does not work yet. These instructions
are here mostly for me to know where to continue debugging, when
there is time.</font>
<p>Preliminary instruction for how to boot the kernel from your real O2:
<pre>
$ <b>gxemul -X -e o2 unix</b>
</pre>
<p>where <tt>unix</tt> is the IP32 kernel. If you do not want to use
the graphical framebuffer (<tt>-X</tt>), you can use lower-case <tt>-x</tt>
to just use an xterm instead.
<p>
<a href="20190526-irix-not-really-working-yet.png"><img src="20190526-irix-not-really-working-yet_small.png"></a>
<pre>
IRIX Release 6.5 IP32 Version 10151453 System V
Copyright 1987-2002 Silicon Graphics, Inc.
All Rights Reserved.
Total real memory = 131072 kbytes
CPU Frequency = 134Mhz
1 CPU(s)
Free small K0 = 0x411 pages (adding 0xa4 pages)
QLFC: running as interrupt thread.
QLFC: using spinlocks.
PCI Configuration Report
keyboard on port 0, mouse on port 1
ec0: hardware ethernet address 08:20:30:00:00:10
919 buffers
PANIC: vfs_mountroot: no root found
[Press reset to restart the machine.]
</pre>
<p><font color="red">Right now, it does not work. There are several problems,
most importantly there is no way to get IRIX to find the root file system
from which to run; SCSI is not emulated, and the network emulation in
GXemul is not good enough for IRIX to accept it for root-on-nfs. Also,
attempting to use more than 256 MB of RAM fails.</font>
<p><br>
<a name="prom"></a>
<h3>Experimenting with a PROM from a real SGI O2</h3>
<p>Note: Normally, a dump of the PROM image from your real SGI O2 is <i>not</i> needed,
if what you want to do is to run guest operating systems in the emulator.
<p>Using a serial console hooked up to your O2, executing the PROM command
<pre>
>> <b>dump -b 0xBFC00000:0xBFC80000</b>
</pre>
<p>
will dump 512 KB of the PROM range. Make sure you capture all the output
into a file, and then convert the result into a raw binary. (If you don't have
time to write a converter tool yourself, there is an example converter in
the GXemul source code distribution: <tt>experiments/sgiprom_to_bin</tt>.)
<p>Assuming you have extracted the PROM from your real machine into a
file called <tt>prom</tt>, the following example shows how to start up the
emulator with that image:
<pre>
$ <b>gxemul -Q -X -e o2 0xbfc00000:prom</b>
</pre>
<p><tt>-Q</tt> turns off GXemul's built-in PROM emulation, allowing raw PROM images
to be used. <tt>-X</tt> is used to display the graphical framebuffer. (<tt>-X</tt> can be
omitted if only serial console is what you want.) And finally, <tt>-e o2</tt> selects
the O2 emulation mode. 0xbfc00000 is the standard ROM address for MIPS-based
systems.
<p>
<a href="sgi-o2-real.jpg"><img src="sgi-o2-real_small.jpg"></a>
<a href="20180910-sgiip32prom-4.13.png"><img src="20180910-sgiip32prom-4.13.png" width=250></a>
<p>The photo on the left is from the real machine. The screenshot to the right
is from the emulator.
<p><font color="#ff0000">
NOTE: The SGI O2 PROM does some hardware tests during startup that do not
work in GXemul, in particular cache detection. So right now,
there is a hack/workaround which skips cache detection in an ugly way.
This has been verified to work with PROM versions 2.3, 4.13, and 4.18.
For other versions, it may need to be manually skipped.</font>
<p>With a IP32 PROM version 4.13 for example, if the hack is commented out,
the cache detection routine at 0xbfc05180 must be skipped:
<pre>
$ <b>gxemul -p 0xffffffffbfc05180 -X -Q -e o2 0xbfc00000:prom-4.13</b>
<i>...
when the breakpoint is hit, type:</i>
pc = ra
continue
</pre>
<p>If the 'console' variable in the PROM's environment variable section
was set to something starting with 'g', output will be graphical, otherwise
it will be to serial console.
<p>Note however that almost nothing works; <b>most importantly, SCSI is not
implemented for the SGI O2</b>, so the emulated machine will not be able
to boot from any kind of disk or CDROM. Audio
or video hardware is not emulated at all yet either.
Also, while the graphics emulation has been implemented well enough to run
NetBSD, OpenBSD, and perhaps also Linux, other things may not work.
<p><br>
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