1.  Timezone

You first need to select your timezone so that your system knows where it is located. Look for your timezone in /usr/share/zoneinfo, then copy it to /etc/localtime. Please avoid the /usr/share/zoneinfo/Etc/GMT* timezones as their names do not indicate the expected zones. For instance, GMT-8 is in fact GMT+8.

# ls /usr/share/zoneinfo
(Suppose you want to use GMT)
# cp /usr/share/zoneinfo/GMT /etc/localtime

1.  Installing the Sources

Choosing a Kernel

The core around which all distributions are built is the Linux kernel. It is the layer between the user programs and your system hardware. Gentoo provides its users several possible kernel sources. A full listing with description is available at the Gentoo Kernel Guide.

MIPS-based systems have just the one kernel tree to choose from, mips-sources. This patchset differs from the ones available for other architectures, in that it has lots of patches specific to the MIPS architecture.

# emerge mips-sources

# emerge kgcc64

When you take a look in /usr/src you should see a symlink called linux pointing to your kernel source. In this case, the installed kernel source points to mips-sources-${kernel-version}. Your version may be different, so keep this in mind.

# ls -l /usr/src/linux
lrwxrwxrwx    1 root     root           12 Oct 13 11:04 /usr/src/linux -> linux-${kernel-version}

Now it is time to configure and compile your kernel source.

1.  Kernel Compilation & Installation

Introduction

Previously, we went through the manual configuration of how to set up the kernel sources. This has become impractical with the number of systems we now support. This section details various sources for sample kernel configurations.

Using sample configurations in the kernel source

Many of the systems supported have sample .configs hiding in amongst the kernel source. Not all systems have configs distributed in this way. Those that do, can be configured using the commands mentioned in the table below.

Using the running kernel config from the installation media

All of the Gentoo installation images provide a kernel config option as part of the image itself, accessible as /proc/config.gz. This may be used in many cases. It is best though if your kernel source matches closely, the kernel that is currently running. To extract it, simply run it through zcat as shown below.

# zcat /proc/config.gz > .config

The Hardware Compatability Database

As an aid to users in finding working settings, a hardware compatability database was set up. This database lists the support for various MIPS devices, and allows users to contribute kernel configurations that are known to work. The address for this site is http://stuartl.longlandclan.hopto.org/gentoo/mips.

If you find this service useful, you're welcome to contribute your notes and .config files so that others may benefit from your experience. It should be noted however that there is no guarantee that any of the configuration files downloaded from this site will work.

Customising the configuration for your needs

Once you have found a configuration, download it into your kernel source directory, and rename it to .config. From there, you can run make oldconfig to bring everything up to date, and allow you to customise the configuration before compiling.

# cd /usr/src/linux
# cp /path/to/example-config .config
# make oldconfig
(Just press ENTER at each prompt to accept the defaults... we'll customise later)
# make menuconfig

Compiling and Installing

Now that your kernel is configured, it is time to compile and install it. Exit the configuration and start the compilation process:

(Compiling natively)
# make vmlinux modules modules_install

(Cross-compiling on target machine)
(Adjust the mips64-unknown-linux-gnu- accordingly)
# make vmlinux modules modules_install CROSS_COMPILE=mips64-unknown-linux-gnu-

(When compiling on another machine, such as an x86 box, use the)
(following commands to compile the kernel & install modules into)
(a specific directory to be transferred to the target machine.)
# make vmlinux modules CROSS_COMPILE=mips64-unknown-linux-gnu-
# make modules_install INSTALL_MOD_PATH=/somewhere

# make vmlinux.32
(This will create vmlinux.32 -- which is your final kernel)

When the kernel has finished compiling, copy the kernel image to /boot.

# cp vmlinux /boot/kernel-${kernel-version}

(Cobalt Servers -- Compressing the kernel image)
# gzip -9v /boot/kernel-${kernel-version}

1.  Kernel Modules

Configuring the Modules

You should list the modules you want automatically loaded in /etc/modules.autoload.d/kernel-2.6. You can add extra options to the modules too if you want.

To view all available modules, run the following find command. Don't forget to substitute "<kernel version>" with the version of the kernel you just compiled:

# find /lib/modules/<kernel version>/ -type f -iname '*.o' -or -iname '*.ko' | less

For instance, to automatically load the 3c59x.ko module, edit the kernel-2.6 file and enter the module name in it.

# nano -w /etc/modules.autoload.d/kernel-2.6

3c59x

Continue the installation with (Configuring your System).