Re: [PATCH v2] docs/system/ppc: Document running Linux on AmigaNG machines

[Nicholas Piggin]

On Tue Feb 20, 2024 at 6:30 AM AEST, BALATON Zoltan wrote:
> Documentation on how to run Linux on the amigaone, pegasos2 and
> sam460ex machines is currently buried in the depths of the qemu-devel
> mailing list and in the source code. Let's collect the information in
> the QEMU handbook for a one stop solution.
>
> Co-authored-by: Bernhard Beschow <shentey@gmail.com>
> Signed-off-by: BALATON Zoltan <balaton@eik.bme.hu>

Reviewed-by: Nicholas Piggin <npiggin@gmail.com>

> ---
> v2:
> Move top level title one level up so subsections will be below it in TOC
>
>  MAINTAINERS                 |   1 +
>  docs/system/ppc/amigang.rst | 161 ++++++++++++++++++++++++++++++++++++
>  docs/system/target-ppc.rst  |   1 +
>  3 files changed, 163 insertions(+)
>  create mode 100644 docs/system/ppc/amigang.rst
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 7d61fb9319..0aef8cb2a6 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -1562,6 +1562,7 @@ F: hw/rtc/m41t80.c
>  F: pc-bios/canyonlands.dt[sb]
>  F: pc-bios/u-boot-sam460ex-20100605.bin
>  F: roms/u-boot-sam460ex
> +F: docs/system/ppc/amigang.rst
>  
>  pegasos2
>  M: BALATON Zoltan <balaton@eik.bme.hu>
> diff --git a/docs/system/ppc/amigang.rst b/docs/system/ppc/amigang.rst
> new file mode 100644
> index 0000000000..738decd0c5
> --- /dev/null
> +++ b/docs/system/ppc/amigang.rst
> @@ -0,0 +1,161 @@
> +=========================================================
> +AmigaNG boards (``amigaone``, ``pegasos2``, ``sam460ex``)
> +=========================================================
> +
> +These PowerPC machines emulate boards that are primarily used for
> +running Amiga like OSes (AmigaOS 4, MorphOS and AROS) but these can
> +also run Linux which is what this section documents.
> +
> +Eyetech AmigaOne/Mai Logic Teron (``amigaone``)
> +===============================================
> +
> +The ``amigaone`` machine emulates an AmigaOne XE mainboard by Eyetech
> +which is a rebranded Mai Logic Teron board with modified U-Boot
> +firmware to support AmigaOS 4.
> +
> +Emulated devices
> +----------------
> +
> + * PowerPC 7457 CPU (can also use``-cpu g3, 750cxe, 750fx`` or ``750gx``)
> + * Articia S north bridge
> + * VIA VT82C686B south bridge
> + * PCI VGA compatible card (guests may need other card instead)
> + * PS/2 keyboard and mouse
> +
> +Firmware
> +--------
> +
> +A firmware binary is necessary for the boot process. It is a modified
> +U-Boot under GPL but its source is lost so it cannot be included in
> +QEMU. A binary is available at
> +https://www.hyperion-entertainment.com/index.php/downloads?view=files&parent=28.
> +The ROM image is in the last 512kB which can be extracted with the
> +following command:
> +
> +.. code-block:: bash
> +
> +  $ tail -c 524288 updater.image > u-boot-amigaone.bin
> +
> +The BIOS emulator in the firmware is unable to run QEMU‘s standard
> +vgabios so ``VGABIOS-lgpl-latest.bin`` is needed instead which can be
> +downloaded from http://www.nongnu.org/vgabios.
> +
> +Running Linux
> +-------------
> +
> +There are some Linux images under the following link that work on the
> +``amigaone`` machine:
> +https://sourceforge.net/projects/amigaone-linux/files/debian-installer/.
> +To boot the system run:
> +
> +.. code-block:: bash
> +
> +  $ qemu-system-ppc -machine amigaone -bios u-boot-amigaone.bin \
> +                    -cdrom "A1 Linux Net Installer.iso" \
> +                    -device 
> ati-vga,model=rv100,romfile=VGABIOS-lgpl-latest.bin
> +
> +From the firmware menu that appears select ``Boot sequence`` →
> +``Amiga Multiboot Options`` and set ``Boot device 1`` to
> +``Onboard VIA IDE CDROM``. Then hit escape until the main screen appears 
> again,
> +hit escape once more and from the exit menu that appears select either
> +``Save settings and exit`` or ``Use settings for this session only``. It may
> +take a long time loading the kernel into memory but eventually it boots and 
> the
> +installer becomes visible. The ``ati-vga`` RV100 emulation is not
> +complete yet so only frame buffer works, DRM and 3D is not available.
> +
> +Genesi/bPlan Pegasos II (``pegasos2``)
> +======================================
> +
> +The ``pegasos2`` machine emulates the Pegasos II sold by Genesi and
> +designed by bPlan. Its schematics are available at
> +https://www.powerdeveloper.org/platforms/pegasos/schematics
> +
> +Emulated devices
> +----------------
> +
> + * PowerPC 7457 CPU (can also use``-cpu g3`` or ``750cxe``)
> + * Marvell MV64361 Discovery II north bridge
> + * VIA VT8231 south bridge
> + * PCI VGA compatible card (guests may need other card instead)
> + * PS/2 keyboard and mouse
> +
> +Firmware
> +--------
> +
> +The Pegasos II board has an Open Firmware compliant ROM based on
> +SmartFirmware but it has some changes that are not open sourced
> +therefore the ROM binary cannot be included in QEMU. An updater was
> +available from bPlan, it can be found here:
> +http://web.archive.org/web/20071021223056/http://www.bplan-gmbh.de/up050404/up050404
> +The ROM image can be extracted from it with the following command:
> +
> +.. code-block:: bash
> +
> +  $ tail -c +85581 up050404 | head -c 524288 > pegasos2.rom
> +
> +Running Linux
> +-------------
> +
> +The PowerPC version of Debian 8.11 supported Pegasos II. The BIOS
> +emulator in the firmware binary is unable to run QEMU‘s standard
> +vgabios so it needs to be disabled. To boot the system run:
> +
> +.. code-block:: bash
> +
> +  $ qemu-system-ppc -machine pegasos2 -bios pegasos2.rom \
> +                    -cdrom debian-8.11.0-powerpc-netinst.iso \
> +                    -device VGA,romfile="" -serial stdio
> +
> +At the firmware ``ok`` prompt enter ``boot cd install/pegasos``.
> +
> +Alternatively it is possible to boot the kernel directly without
> +firmware ROM using the QEMU built in minimal Virtual Open Firmware
> +(VOF) emulation which is also supported on ``pegasos2``. For this,
> +extract the kernel ``install/powerpc/vmlinuz-chrp.initrd`` from the CD
> +image then run:
> +
> +.. code-block:: bash
> +
> +  $ qemu-system-ppc -machine pegasos2 -serial stdio \
> +                    -kernel vmlinuz-chrp.initrd -append "---" \
> +                    -cdrom debian-8.11.0-powerpc-netinst.iso
> +
> +aCube Sam460ex (``sam460ex``)
> +=============================
> +
> +The ``sam460ex`` machine emulates the Sam460ex board by aCube which is
> +based on the AMCC PowerPC 460EX SoC (that despite its name has a
> +PPC440 CPU core).
> +
> +Firmware
> +--------
> +
> +The board has a firmware based on an older U-Boot version with
> +modifications to support booting AmigaOS 4. The firmware ROM is
> +included with QEMU.
> +
> +Emulated devices
> +----------------
> +
> + * PowerPC 460EX SoC
> + * M41T80 serial RTC chip
> + * Silicon Motion SM501 display parts (identical to SM502 on real board)
> + * Silicon Image SiI3112 2 port SATA controller
> + * USB keyboard and mouse
> +
> +Running Linux
> +-------------
> +
> +The only Linux distro that supported Sam460ex out of box was CruxPPC
> +2.x. It can be booted by running:
> +
> +.. code-block:: bash
> +
> +  $ qemu-system-ppc -machine sam460ex -serial stdio \
> +                    -drive if=none,id=cd,format=raw,file=crux-ppc-2.7a.iso \
> +                    -device ide-cd,drive=cd,bus=ide.1
> +
> +There are some other kernels and instructions for booting other
> +distros on aCube's product page at
> +https://www.acube-systems.biz/index.php?page=hardware&pid=5
> +but those are untested.
> diff --git a/docs/system/target-ppc.rst b/docs/system/target-ppc.rst
> index 4f6eb93b17..87bf412ce5 100644
> --- a/docs/system/target-ppc.rst
> +++ b/docs/system/target-ppc.rst
> @@ -17,6 +17,7 @@ help``.
>  .. toctree::
>     :maxdepth: 1
>  
> +   ppc/amigang
>     ppc/embedded
>     ppc/powermac
>     ppc/powernv