VR2000 Linux Kernel

The VR2000 runs a custom Linux 2.6 kernel, which at the time of writing is based in on the 2.6.11-bk10 (2.6.11 pre-release) plus patches for VR2000 specific hardware support.

Information in this section is provided to allow third parties to build and install a Linux kernel on the VR2000 and to make the Thorcom provided kernel patches available under the terms of the GNU Public Licence.

Note that these instructions and patches, while beleived to be correct, are provided "AS IS" and "WITHOUT WARRANTY" - if you have a problem please report it to Thorcom supoprt by email to support@thorcom.co.uk.

In order to build, install and run the kernel you will need the folllowing:

1. A VR2000 with an existing CF card and bootable operating system
2. An i386 based Linux machine (eg. RedHat 9, Fedora Core 3, etc.)
3. GCC cross compiler for ARM (GCC 3.4.3 cross)
4. Linux 2.6.11 stock kernel
5. Linux 2.6.11-bk10 kernel patch set
6. Thorcom VR2000 patch set "bk10-thorcom5"
7. Thorcom VR2000 default kernel configuration file (".config")
8. Thorcom VR2000 makefile scripts

Working in a suitable directory, such as /usr/src/VR2000, the following will unpack and patch the sources:

   tar -jxf linux-2.6.11.tar.bz2
   mv linux-2.6.11 linux-2.6.11-bk10-thorcom5
   cd linux-2.6.11-bk10-thorcom5
   bzcat ../patch-2.6.11-bk10.bz2 | patch -p1
   bzcat ../2611-bk10-thcom5.diffs.bz2 | patch -p1

Next either use the appropriate script "make_VR2000_kernel" for a modular kernel or "make_monolithic_kernel" for a monolithic kernel or use the GCC cross compiler by hand.

The configuration that Thorcom uses as a base for its VR2000 kernels ("default_kernel_config" above) may be used with the "make_config_old" script to make a kernel configuration with the same options and settings as used by Thorcom.

There are three main ways in which the kernel can be installed to an existing VR2000:

1. copy the kernel on to an already working VR2000 (recommended)
2. copy the kernel on to a CF card and boot from it
3. network boot using TFTP (advanced users only)

The first option is the easiest - using FTP or SCP copy the kernel binary and system map to the /boot directory, copy the modules to the relevant /lib/modules directory (if using a modular kernel), update the symbolic links and reboot the unit.

The second method can also be used if you have a CF card reader on the compile host, in which case the CF card from the VR2000 can have the files copied directly to the appropriate directories. The VR2000 CF card normally has two partitions on it /dev/hda1 which is ext2 format and contains the operating system, boot directory, etc. and /dev/hda2 which is usually formatted as FAT16 and contains customer data.

The VR2000 does not require a boot loader like LILO or GRUB because the onboard Advanced Boot Loader Environment (ABLE) can read ext2 file systems directly and boot from them. For further details please see the VR2000 Reference Manual.