Boot issues with debian-installer on ppc64

[John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>]

Hello,

I have done some debugging on ppc64 to find out why the the kernel no
longer boots on PowerPC G5 (PowerPC 970) systems.

It turns out that the issue is much more complicated than I expected since
the same kernel that doesn't boot debian-installer boots perfectly fine
when installed after installation.

I used QEMU for testing using the 970 CPU type (-cpu 970) and Mac99 machine
type (-M mac99). I used a 32-bit system (powerpc) and installed a 64-bit
kernel which works both fine with the 6.6.15 and 6.7 kernels.

The same kernels don't work when used to boot debian-installer, I created
test images here:

> https://cdimage.debian.org/cdimage/ports/tests/ppc64-test/debian-12.0.0-ppc64-NETINST-1.iso
> https://cdimage.debian.org/cdimage/ports/tests/ppc64-test-new/debian-12.0.0-ppc64-NETINST-1.iso

There is also an updated debian-installer image for ppc64 with the 6.6.15 kernel:

> https://cdimage.debian.org/cdimage/ports/snapshots/2024-02-25/

Would be great if anyone on this list with a PowerMac G5 ready for testing
could check whether any of the images above boot on their machine.

Thanks,
Adrian

-- 
 .''`.  John Paul Adrian Glaubitz
: :' :  Debian Developer
`. `'   Physicist
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