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 * MPC8540 (for this one, you can use Debian's regular powerpc port with activated FPU emulation in the Kernel)  * MPC8540 (for this one, you can use Debian's regular powerpc port with activated FPU emulation in the kernel)

Maintainer's Note on IBM Cell and PS3 systems

"PowerPC SPE" refers to the "Signal Processing Engine" hardware present on low-power 32-bit ?FreeScale and IBM "e500" cores. If you wish to run Debian on a PS3 or other IBM-Cell-based system, you should instead use the standard powerpc port. The "SPE" in the "powerpcspe" architecture does not refer to the "Synergistic Processing Element" units on IBM Cell microprocessors, although both are PowerPC variants. See also http://lists.debian.org/debian-devel/2011/06/msg00592.html

Current status

The powerpcspe port is currently at ~90% source package (for arch:powerpcspe) completeness, as you will find on the status pages. You can use a regular mirror from the Debian Ports mirror network, e.g.:

deb http://ftp.de.debian.org/debian-ports/ unstable main
deb http://ftp.de.debian.org/debian-ports/ unreleased main

Not all porting efforts are integrated into Debian unstable yet, therefore the "unreleased" distribution of Debian Ports needs to be used additionally.

Experimental packages are available from:

deb http://ftp.de.debian.org/debian-ports/ experimental main

Current 'powerpcspe' bug list

PowerpcSPE specific type-handling

Repositories and Build Status

Hosting for the unofficial PowerPCSPE port is graciously provided by the wonderful people at debian-ports.org. In particular we'd like to thank Aurelien Jarno for his help getting everything set up.

Latest Statistics

Architecture summary

The 'powerpcspe' architecture is a binary-incompatible variant of the PowerPC/POWER designed and supported by FreeScale and IBM. It is also known under the trade names "e500"/"MPC8500" and "e200"/"MPC5xx".

Additional information can be found at:

Supported CPUs

The following CPUs are supported by Debian's powerpcspe/e500v2 port:

  • MPC8548
  • P1011/P1020
  • P2020

The following CPUs are known to not working with this port:

  • MPC8540 (for this one, you can use Debian's regular powerpc port with activated FPU emulation in the kernel)

Instruction set

In particular, the 'powerpcspe' architecture lacks the classic FPU with dedicated FPRs found on most other PowerPC systems. It is replaced with a set of "SPE" instructions which perform floating-point operations on the integer registers.

In an unfortunate choice of architecture design, the instructions used for the "SPE" operations overlap with those for the Altivec unit on most other modern PowerPC cores.

Chipset details

The "e500v2"-series chips have 64-bit GPRs, where the high 32-bits are accessible only via the special "SPE" instructions, allowing them to make efficient use of the "double" datatype.

The relatively rare "e500v1"-series chips have only 32-bit GPRs, and require software traps and emulation to support native "double".

The "e200z3" and "e200z6" chips have no support for floating point at all, but with software traps and emulation are binary-compatible with the "e500"-series chips.

GCC/EGLIBC considerations

The Debian port to this architecture specifically chooses to optimize for the higher-end chips (e500v2), as most of the others are targeted at automotive applications or no longer in production.

Full support for the e500v2 requires the following options to GCC's "configure":

  •  --with-cpu=8548 

  •  --enable-e500_double 

  •  --with-long-double-128 

Please note that the  --with-long-double-128  is desired to match the behavior of long double on other PowerPC-based platforms. (Otherwise long double is exactly the same as double).

Installing the port

Installation can be done with debootstrap:

# debootstrap --no-check-gpg unstable rootfs-powerpcspe http://antcom.de/powerpcspe/

An intermediate repository is provided, because debootstrap doesn't accept sources from multiple distributions like here with sources from unstable and unreleased. As the repository at antcom.de is a bit outdated, you should apt-get dist-upgrade after bootstrapping.

Or, to cross-bootstrap, do:

# debootstrap --foreign --arch=powerpcspe --no-check-gpg unstable rootfs-powerpcspe http://antcom.de/powerpcspe/

Afterwards, on the target, chroot to this directory and finish the installation with:

# /debootstrap/debootstrap --second-stage
  • if you need a console on ttyS0:
    • edit etc/inittab and add a line like T0:23:respawn:/sbin/getty -L ttyS0 115200 vt100

    • make sure /dev/ttyS0 exist. Either install udev or use the following command mknod ttyS0 c 4 64

  • edit etc/apt/sources.list and enter a mirror from here which is close to you.

Porters

During the last several years, the following people have been working on this port:

  • Sebastian Andrzej Siewior
  • Kyle Moffett
  • Roland Stigge (currently active porter)

Final notes

At this time the 'powerpcspe' architecture port is still very much an unofficial port. While we hope that will change in the future, it is entirely possible that the embedded niche of the processor will make such an official Debian port problematic.