This section will walk you through pre-installation hardware setup, if any, that you will need to do prior to installing Debian. Generally, this involves checking and possibly changing BIOS/system firmware settings for your system. The “BIOS” or “system firmware” is the core software used by the hardware; it is most critically invoked during the bootstrap process (after power-up).
There is normally no need to set up the BIOS (called OpenFirmware) on PowerPC systems. PReP and CHRP are equipped with OpenFirmware, but unfortunately, the means you use to invoke it vary from manufacturer to manufacturer. You'll have to consult the hardware documentation which came with your machine.
On PowerPC Macintoshes, you invoke OpenFirmware with Command (cloverleaf/Apple)+Option+o+f while booting. Generally it will check for these keystrokes after the chime, but the exact timing varies from model to model. See http://www.netbsd.org/Ports/macppc/faq.html for more hints.
The OpenFirmware prompt looks like this:
ok 0 >
Note that on older model PowerPC Macs, the default and sometimes hardwired I/O for OpenFirmware user interaction is through the serial (modem) port. If you invoke OpenFirmware on one of these machines, you will just see a black screen. In that case, a terminal program running on another computer, connected to the modem port, is needed to interact with OpenFirmware.
The OpenFirmware on OldWorld Beige G3 machines, OF versions 2.0f1 and 2.4, is broken. These machines will most likely not be able to boot from the hard drive unless the firmware is patched. A firmware patch is included in the System Disk 2.3.1 utility, available from Apple at ftp://ftp.apple.com/developer/macosxserver/utilities/SystemDisk2.3.1.smi.bin. After unpacking the utility in MacOS, and launching it, select the button to have the firmware patches installed to nvram.
This is an excerpt from IBM PowerKVM on IBM POWER8
Open Power Abstraction Layer (OPAL) is the system firmware in the stack of POWER processor-based server.
There may be instances when the user might have to upgrade the Power Systems firmware to a more recent level to acquire new features or additional support for devices.
Make sure that the following requirements are met:
an OS to be running on the system;
the .img file of the OPAL level that the user needs to update to;
the machine isn't under HMC control.
Power Systems has two sides of flash to boot firmware from, namely permanent and temporary. This provides a way to test firmware updates on the temporary side of the flash before committing the tested changes to the permanent side, thereby committing the new updates.
Perform the following steps for the update:
Save the level of the existing firmware before really updating. In ASM, in the system menu, click Service Aids ??? Service Processor Command Line, and run the following command:
Download the .img file of the level of firmware to be updated to a location in the host filesystem. Refer to IBM Fix Central for downloading the image file.
Verify the image downloaded by running the following command and save the output.
$update_flash -v -f <file_name.img>
Update the firmware by running the following command.
$update_flash -f <file_name.img>
Verify the updated firmware level of the temporary side of the flash as in step 1.
In case the update has to be reverted, the user can do so by running this command:
Rejection would reject only the temporary side of the flash. Therefore, the new level should be committed to the permanent side only after thorough testing of the new firmware.
The new updated level can be committed to the permanent side of the flash by running the following command.
Slimline Open Firmware (SLOF) is an implementation of the IEEE 1275 standard. It can be used as partition firmware for pSeries machines running on QEMU or KVM.
The package qemu-slof is, in fact, a dependency of package qemu-system-ppc (which also provides the virtual package qemu-system-ppc64), and can be installed or updated via apt-get tool on Debian-based distros. Like so:
# apt-get install qemu-slof
SLOF can also be installed into rpm-based distribution systems, given the proper repository or rpm package. Additionally, the upstream source code is available at http://github.com/leilihh/SLOF.
Thus, one can use a different SLOF file rather than the default, when
running qemu-system, by adding the command line
-bios <slof_file> when starting
Display-visibility on OldWorld Powermacs. Some OldWorld Powermacs, most notably those with the “control” display driver, may not reliably produce a colormap under Linux when the display is configured for more than 256 colors. If you are experiencing such issues with your display after rebooting (you can sometimes see data on the monitor, but on other occasions cannot see anything) or, if the screen turns black after booting the installer instead of showing you the user interface, try changing your display settings under MacOS to use 256 colors instead of “thousands” or “millions”.