Debian VME PPC

Some notes on bringing up a system in a way other than the way the Boot-Floppies people provide.

About the hardware…

There is a lot of documentation available from the Motorola Computer group VMEbus Boards web page.

It is common to find one of these computers without an attached floppy disk, CD-ROM drive, or even hard disk. With the MVME2300 - there are not even connectors for those devices, and there is no keyboard or video monitor. (Serial console and network is all that is on the front panel.) In general, one boots these over the network interface from some host.

Planning your new network

Come up with at least a list of entries for your /etc/hosts to use on various platforms.

Preparing a Host

There may be more than one way to do this, but this does work:

• rarpd

  Configure /etc/ethers with Ethernet address of PPC board and IP
  address pair.
  

• tftp

  Configure inetd (or xinetd) to run tftpd.
  

• nfs -

  # /etc/exports: the access control list for filesystems which may be exported
  #		to NFS clients.  See exports(5).
  /tftpboot/192.168.1.2	-rw,root=192.168.1.2 192.168.1.2(rw,no_root_squash)
  

Preparing the PPC filesystem

Finding a Debian base system tarball

There is one for Potato at:

• /debian/dists/potato/main/disks-powerpc/current/base2_2.tgz

Extract it under /tftpboot/[IP dotted quad]/

Configuring the Base System by hand

Since the normal boot-floppies configuration is bypassed...

• etc/hostname
• etc/hosts
• etc/resolv.conf
• etc/securetty - maybe list ttyS0 as one so root can login
• etc/fstab - remember, no need to fsck NFS mounts
• move sbin/unconfigured.sh out of the way

About the PPC kernel image

The Boot-Floppies people may be doing something new, but at the time this is written, I had to make my own Network-Booting PPC kernel. One is available here. This kernel has the boot prompt commands

console=ttyS0,9600 root=/dev/nfs ip=both

The kernel configuration parameters I used are here. The 2.4.19pre1 menuconfig did not let me set CONFIG_ROOT_NFS, so I did it by hand. Dunno what was up with that - hopefully that has been fixed by now.

The kernel image file zImage.prep needs to be placed in the directory where tftpd will serve it when asked.

Special considerations…

Tundra Universe PCI-VME Bridge

See VME Linux Project pages. Hopefully a new version of the Tundra Universe driver which handles the PPC memory architecture correctly will be there. (Some notes on bringing up the driver are at this message in the vmelinux-users mailing list archive.